6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
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111 Permission is granted to copy, distribute and/or modify this document
112 under the terms of the GNU Free Documentation License, Version 1.3 or
113 any later version published by the Free Software Foundation; with no
114 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
115 copy of the license is included in the section entitled ``GNU Free
116 Documentation License''.
119 @dircategory System administration
121 * Guix: (guix). Manage installed software and system configuration.
122 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
123 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
124 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
125 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
126 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
129 @dircategory Software development
131 * guix shell: (guix)Invoking guix shell. Creating software environments.
132 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
133 * guix build: (guix)Invoking guix build. Building packages.
134 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
138 @title GNU Guix Reference Manual
139 @subtitle Using the GNU Guix Functional Package Manager
140 @author The GNU Guix Developers
143 @vskip 0pt plus 1filll
144 Edition @value{EDITION} @*
152 @c *********************************************************************
156 This document describes GNU Guix version @value{VERSION}, a functional
157 package management tool written for the GNU system.
159 @c TRANSLATORS: You can replace the following paragraph with information on
160 @c how to join your own translation team and how to report issues with the
162 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
163 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
164 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
165 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
166 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
167 would like to translate it in your native language, consider joining
168 @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
169 Weblate} (@pxref{Translating Guix}).
172 * Introduction:: What is Guix about?
173 * Installation:: Installing Guix.
174 * System Installation:: Installing the whole operating system.
175 * System Troubleshooting Tips:: When things don't go as planned.
176 * Getting Started:: Your first steps.
177 * Package Management:: Package installation, upgrade, etc.
178 * Channels:: Customizing the package collection.
179 * Development:: Guix-aided software development.
180 * Programming Interface:: Using Guix in Scheme.
181 * Utilities:: Package management commands.
182 * Foreign Architectures:: Build for foreign architectures.
183 * System Configuration:: Configuring the operating system.
184 * Home Configuration:: Configuring the home environment.
185 * Documentation:: Browsing software user manuals.
186 * Installing Debugging Files:: Feeding the debugger.
187 * Using TeX and LaTeX:: Typesetting.
188 * Security Updates:: Deploying security fixes quickly.
189 * Bootstrapping:: GNU/Linux built from scratch.
190 * Porting:: Targeting another platform or kernel.
191 * Contributing:: Your help needed!
193 * Acknowledgments:: Thanks!
194 * GNU Free Documentation License:: The license of this manual.
195 * Concept Index:: Concepts.
196 * Programming Index:: Data types, functions, and variables.
199 --- The Detailed Node Listing ---
203 * Managing Software the Guix Way:: What's special.
204 * GNU Distribution:: The packages and tools.
208 * Binary Installation:: Getting Guix running in no time!
209 * Requirements:: Software needed to build and run Guix.
210 * Running the Test Suite:: Testing Guix.
211 * Setting Up the Daemon:: Preparing the build daemon's environment.
212 * Invoking guix-daemon:: Running the build daemon.
213 * Application Setup:: Application-specific setup.
214 * Upgrading Guix:: Upgrading Guix and its build daemon.
216 Setting Up the Daemon
218 * Build Environment Setup:: Preparing the isolated build environment.
219 * Daemon Offload Setup:: Offloading builds to remote machines.
220 * SELinux Support:: Using an SELinux policy for the daemon.
224 * Limitations:: What you can expect.
225 * Hardware Considerations:: Supported hardware.
226 * USB Stick and DVD Installation:: Preparing the installation medium.
227 * Preparing for Installation:: Networking, partitioning, etc.
228 * Guided Graphical Installation:: Easy graphical installation.
229 * Manual Installation:: Manual installation for wizards.
230 * After System Installation:: When installation succeeded.
231 * Installing Guix in a VM:: Guix System playground.
232 * Building the Installation Image:: How this comes to be.
234 System Troubleshooting Tips
236 * Chrooting into an existing system:: Fixing things from a chroot
240 * Keyboard Layout and Networking and Partitioning:: Initial setup.
241 * Proceeding with the Installation:: Installing.
245 * Features:: How Guix will make your life brighter.
246 * Invoking guix package:: Package installation, removal, etc.
247 * Substitutes:: Downloading pre-built binaries.
248 * Packages with Multiple Outputs:: Single source package, multiple outputs.
249 * Invoking guix gc:: Running the garbage collector.
250 * Invoking guix pull:: Fetching the latest Guix and distribution.
251 * Invoking guix time-machine:: Running an older revision of Guix.
252 * Inferiors:: Interacting with another revision of Guix.
253 * Invoking guix describe:: Display information about your Guix revision.
254 * Invoking guix archive:: Exporting and importing store files.
258 * Official Substitute Servers:: One particular source of substitutes.
259 * Substitute Server Authorization:: How to enable or disable substitutes.
260 * Getting Substitutes from Other Servers:: Substitute diversity.
261 * Substitute Authentication:: How Guix verifies substitutes.
262 * Proxy Settings:: How to get substitutes via proxy.
263 * Substitution Failure:: What happens when substitution fails.
264 * On Trusting Binaries:: How can you trust that binary blob?
268 * Specifying Additional Channels:: Extending the package collection.
269 * Using a Custom Guix Channel:: Using a customized Guix.
270 * Replicating Guix:: Running the @emph{exact same} Guix.
271 * Channel Authentication:: How Guix verifies what it fetches.
272 * Channels with Substitutes:: Using channels with available substitutes.
273 * Creating a Channel:: How to write your custom channel.
274 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
275 * Declaring Channel Dependencies:: How to depend on other channels.
276 * Specifying Channel Authorizations:: Defining channel authors authorizations.
277 * Primary URL:: Distinguishing mirror to original.
278 * Writing Channel News:: Communicating information to channel's users.
282 * Invoking guix shell:: Spawning one-off software environments.
283 * Invoking guix environment:: Setting up development environments.
284 * Invoking guix pack:: Creating software bundles.
285 * The GCC toolchain:: Working with languages supported by GCC.
286 * Invoking guix git authenticate:: Authenticating Git repositories.
288 Programming Interface
290 * Package Modules:: Packages from the programmer's viewpoint.
291 * Defining Packages:: Defining new packages.
292 * Defining Package Variants:: Customizing packages.
293 * Writing Manifests:: The bill of materials of your environment.
294 * Build Systems:: Specifying how packages are built.
295 * Build Phases:: Phases of the build process of a package.
296 * Build Utilities:: Helpers for your package definitions and more.
297 * Search Paths:: Declaring search path environment variables.
298 * The Store:: Manipulating the package store.
299 * Derivations:: Low-level interface to package derivations.
300 * The Store Monad:: Purely functional interface to the store.
301 * G-Expressions:: Manipulating build expressions.
302 * Invoking guix repl:: Programming Guix in Guile.
303 * Using Guix Interactively:: Fine-grain interaction at the REPL.
307 * package Reference:: The package data type.
308 * origin Reference:: The origin data type.
312 * Invoking guix build:: Building packages from the command line.
313 * Invoking guix edit:: Editing package definitions.
314 * Invoking guix download:: Downloading a file and printing its hash.
315 * Invoking guix hash:: Computing the cryptographic hash of a file.
316 * Invoking guix import:: Importing package definitions.
317 * Invoking guix refresh:: Updating package definitions.
318 * Invoking guix style:: Styling package definitions.
319 * Invoking guix lint:: Finding errors in package definitions.
320 * Invoking guix size:: Profiling disk usage.
321 * Invoking guix graph:: Visualizing the graph of packages.
322 * Invoking guix publish:: Sharing substitutes.
323 * Invoking guix challenge:: Challenging substitute servers.
324 * Invoking guix copy:: Copying to and from a remote store.
325 * Invoking guix container:: Process isolation.
326 * Invoking guix weather:: Assessing substitute availability.
327 * Invoking guix processes:: Listing client processes.
329 Invoking @command{guix build}
331 * Common Build Options:: Build options for most commands.
332 * Package Transformation Options:: Creating variants of packages.
333 * Additional Build Options:: Options specific to 'guix build'.
334 * Debugging Build Failures:: Real life packaging experience.
336 Foreign Architectures
337 * Cross-Compilation:: Cross-compiling for another architecture.
338 * Native Builds:: Targeting another architecture through native builds.
342 * Using the Configuration System:: Customizing your GNU system.
343 * operating-system Reference:: Detail of operating-system declarations.
344 * File Systems:: Configuring file system mounts.
345 * Mapped Devices:: Block device extra processing.
346 * Swap Space:: Backing RAM with disk space.
347 * User Accounts:: Specifying user accounts.
348 * Keyboard Layout:: How the system interprets key strokes.
349 * Locales:: Language and cultural convention settings.
350 * Services:: Specifying system services.
351 * Setuid Programs:: Programs running with elevated privileges.
352 * X.509 Certificates:: Authenticating HTTPS servers.
353 * Name Service Switch:: Configuring libc's name service switch.
354 * Initial RAM Disk:: Linux-Libre bootstrapping.
355 * Bootloader Configuration:: Configuring the boot loader.
356 * Invoking guix system:: Instantiating a system configuration.
357 * Invoking guix deploy:: Deploying a system configuration to a remote host.
358 * Running Guix in a VM:: How to run Guix System in a virtual machine.
359 * Defining Services:: Adding new service definitions.
361 Home Environment Configuration
363 * Invoking guix home:: Instantiating a home environment configuration.
367 * Base Services:: Essential system services.
368 * Scheduled Job Execution:: The mcron service.
369 * Log Rotation:: The rottlog service.
370 * Networking Setup:: Setting up network interfaces.
371 * Networking Services:: Firewall, SSH daemon, etc.
372 * Unattended Upgrades:: Automated system upgrades.
373 * X Window:: Graphical display.
374 * Printing Services:: Local and remote printer support.
375 * Desktop Services:: D-Bus and desktop services.
376 * Sound Services:: ALSA and Pulseaudio services.
377 * Database Services:: SQL databases, key-value stores, etc.
378 * Mail Services:: IMAP, POP3, SMTP, and all that.
379 * Messaging Services:: Messaging services.
380 * Telephony Services:: Telephony services.
381 * Monitoring Services:: Monitoring services.
382 * Kerberos Services:: Kerberos services.
383 * LDAP Services:: LDAP services.
384 * Web Services:: Web servers.
385 * Certificate Services:: TLS certificates via Let's Encrypt.
386 * DNS Services:: DNS daemons.
387 * VPN Services:: VPN daemons.
388 * Network File System:: NFS related services.
389 * Samba Services:: Samba services.
390 * Continuous Integration:: Cuirass and Laminar services.
391 * Power Management Services:: Extending battery life.
392 * Audio Services:: The MPD.
393 * Virtualization Services:: Virtualization services.
394 * Version Control Services:: Providing remote access to Git repositories.
395 * Game Services:: Game servers.
396 * PAM Mount Service:: Service to mount volumes when logging in.
397 * Guix Services:: Services relating specifically to Guix.
398 * Linux Services:: Services tied to the Linux kernel.
399 * Hurd Services:: Services specific for a Hurd System.
400 * Miscellaneous Services:: Other services.
404 * Service Composition:: The model for composing services.
405 * Service Types and Services:: Types and services.
406 * Service Reference:: API reference.
407 * Shepherd Services:: A particular type of service.
408 * Complex Configurations:: Defining bindings for complex configurations.
410 Installing Debugging Files
412 * Separate Debug Info:: Installing 'debug' outputs.
413 * Rebuilding Debug Info:: Building missing debug info.
417 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
418 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
423 @c *********************************************************************
425 @chapter Introduction
428 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
429 using the international phonetic alphabet (IPA).} is a package
430 management tool for and distribution of the GNU system.
431 Guix makes it easy for unprivileged
432 users to install, upgrade, or remove software packages, to roll back to a
433 previous package set, to build packages from source, and generally
434 assists with the creation and maintenance of software environments.
437 @cindex GuixSD, now Guix System
438 @cindex Guix System Distribution, now Guix System
439 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
440 complements the available tools without interference (@pxref{Installation}),
441 or you can use it as a standalone operating system distribution,
442 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
443 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
444 group everything under the ``Guix'' banner since, after all, Guix System is
445 readily available through the @command{guix system} command, even if you're
446 using a different distro underneath!}. @xref{GNU Distribution}.
449 * Managing Software the Guix Way:: What's special.
450 * GNU Distribution:: The packages and tools.
453 @node Managing Software the Guix Way
454 @section Managing Software the Guix Way
456 @cindex user interfaces
457 Guix provides a command-line package management interface
458 (@pxref{Package Management}), tools to help with software development
459 (@pxref{Development}), command-line utilities for more advanced usage
460 (@pxref{Utilities}), as well as Scheme programming interfaces
461 (@pxref{Programming Interface}).
463 Its @dfn{build daemon} is responsible for building packages on behalf of
464 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
465 binaries from authorized sources (@pxref{Substitutes}).
467 @cindex extensibility of the distribution
468 @cindex customization, of packages
469 Guix includes package definitions for many GNU and non-GNU packages, all
470 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
471 user's computing freedom}. It is @emph{extensible}: users can write
472 their own package definitions (@pxref{Defining Packages}) and make them
473 available as independent package modules (@pxref{Package Modules}). It
474 is also @emph{customizable}: users can @emph{derive} specialized package
475 definitions from existing ones, including from the command line
476 (@pxref{Package Transformation Options}).
478 @cindex functional package management
480 Under the hood, Guix implements the @dfn{functional package management}
481 discipline pioneered by Nix (@pxref{Acknowledgments}).
482 In Guix, the package build and installation process is seen
483 as a @emph{function}, in the mathematical sense. That function takes inputs,
484 such as build scripts, a compiler, and libraries, and
485 returns an installed package. As a pure function, its result depends
486 solely on its inputs---for instance, it cannot refer to software or
487 scripts that were not explicitly passed as inputs. A build function
488 always produces the same result when passed a given set of inputs. It
489 cannot alter the environment of the running system in
490 any way; for instance, it cannot create, modify, or delete files outside
491 of its build and installation directories. This is achieved by running
492 build processes in isolated environments (or @dfn{containers}), where only their
493 explicit inputs are visible.
496 The result of package build functions is @dfn{cached} in the file
497 system, in a special directory called @dfn{the store} (@pxref{The
498 Store}). Each package is installed in a directory of its own in the
499 store---by default under @file{/gnu/store}. The directory name contains
500 a hash of all the inputs used to build that package; thus, changing an
501 input yields a different directory name.
503 This approach is the foundation for the salient features of Guix: support
504 for transactional package upgrade and rollback, per-user installation, and
505 garbage collection of packages (@pxref{Features}).
508 @node GNU Distribution
509 @section GNU Distribution
512 Guix comes with a distribution of the GNU system consisting entirely of
513 free software@footnote{The term ``free'' here refers to the
514 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
515 users of that software}.}. The
516 distribution can be installed on its own (@pxref{System Installation}),
517 but it is also possible to install Guix as a package manager on top of
518 an installed GNU/Linux system (@pxref{Installation}). When we need to
519 distinguish between the two, we refer to the standalone distribution as
522 The distribution provides core GNU packages such as GNU libc, GCC, and
523 Binutils, as well as many GNU and non-GNU applications. The complete
524 list of available packages can be browsed
525 @url{https://www.gnu.org/software/guix/packages,on-line} or by
526 running @command{guix package} (@pxref{Invoking guix package}):
529 guix package --list-available
532 Our goal is to provide a practical 100% free software distribution of
533 Linux-based and other variants of GNU, with a focus on the promotion and
534 tight integration of GNU components, and an emphasis on programs and
535 tools that help users exert that freedom.
537 Packages are currently available on the following platforms:
542 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
545 Intel 32-bit architecture (IA32), Linux-Libre kernel.
548 ARMv7-A architecture with hard float, Thumb-2 and NEON,
549 using the EABI hard-float application binary interface (ABI),
550 and Linux-Libre kernel.
553 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
556 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
559 This configuration is experimental and under development. The easiest
560 way for you to give it a try is by setting up an instance of
561 @code{hurd-vm-service-type} on your GNU/Linux machine
562 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
563 @xref{Contributing}, on how to help!
565 @item mips64el-linux (unsupported)
566 little-endian 64-bit MIPS processors, specifically the Loongson series,
567 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
568 supported; in particular, there is no ongoing work to ensure that this
569 architecture still works. Should someone decide they wish to revive this
570 architecture then the code is still available.
572 @item powerpc-linux (unsupported)
573 big-endian 32-bit PowerPC processors, specifically the PowerPC G4 with
574 AltiVec support, and Linux-Libre kernel. This configuration is not
575 fully supported and there is no ongoing work to ensure this architecture
578 @item powerpc64le-linux
579 little-endian 64-bit Power ISA processors, Linux-Libre kernel. This
580 includes POWER9 systems such as the
581 @uref{https://www.fsf.org/news/talos-ii-mainboard-and-talos-ii-lite-mainboard-now-fsf-certified-to-respect-your-freedom,
582 RYF Talos II mainboard}. This platform is available as a "technology
583 preview": although it is supported, substitutes are not yet available
584 from the build farm (@pxref{Substitutes}), and some packages may fail to
585 build (@pxref{Tracking Bugs and Patches}). That said, the Guix
586 community is actively working on improving this support, and now is a
587 great time to try it and get involved!
590 little-endian 64-bit RISC-V processors, specifically RV64GC, and
591 Linux-Libre kernel. This platform is available as a "technology preview":
592 although it is supported, substitutes are not yet available from the
593 build farm (@pxref{Substitutes}), and some packages may fail to build
594 (@pxref{Tracking Bugs and Patches}). That said, the Guix community is
595 actively working on improving this support, and now is a great time to
596 try it and get involved!
600 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
601 configuration and Guix takes care of instantiating the configuration in a
602 transactional, reproducible, and stateless fashion (@pxref{System
603 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
604 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
605 Manual}), the well-known GNU utilities and tool chain, as well as the
606 graphical environment or system services of your choice.
608 Guix System is available on all the above platforms except
609 @code{mips64el-linux}, @code{powerpc-linux}, @code{powerpc64le-linux} and
610 @code{riscv64-linux}.
613 For information on porting to other architectures or kernels,
616 Building this distribution is a cooperative effort, and you are invited
617 to join! @xref{Contributing}, for information about how you can help.
620 @c *********************************************************************
622 @chapter Installation
624 @cindex installing Guix
627 We recommend the use of this
628 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
629 shell installer script} to install Guix on top of a running GNU/Linux system,
630 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
631 with the installation of the package manager, which can be done on top of a
632 running GNU/Linux system. If, instead, you want to install the complete GNU
633 operating system, @pxref{System Installation}.} The script automates the
634 download, installation, and initial configuration of Guix. It should be run
638 @cindex foreign distro
639 @cindex directories related to foreign distro
640 When installed on a foreign distro, GNU@tie{}Guix complements the available
641 tools without interference. Its data lives exclusively in two directories,
642 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
643 such as @file{/etc}, are left untouched.
645 Once installed, Guix can be updated by running @command{guix pull}
646 (@pxref{Invoking guix pull}).
648 If you prefer to perform the installation steps manually or want to tweak
649 them, you may find the following subsections useful. They describe the
650 software requirements of Guix, as well as how to install it manually and get
654 * Binary Installation:: Getting Guix running in no time!
655 * Requirements:: Software needed to build and run Guix.
656 * Running the Test Suite:: Testing Guix.
657 * Setting Up the Daemon:: Preparing the build daemon's environment.
658 * Invoking guix-daemon:: Running the build daemon.
659 * Application Setup:: Application-specific setup.
660 * Upgrading Guix:: Upgrading Guix and its build daemon.
663 @node Binary Installation
664 @section Binary Installation
666 @cindex installing Guix from binaries
667 @cindex installer script
668 This section describes how to install Guix on an arbitrary system from a
669 self-contained tarball providing binaries for Guix and for all its
670 dependencies. This is often quicker than installing from source, which
671 is described in the next sections. The only requirement is to have
674 @c Note duplicated from the ``Installation'' node.
676 We recommend the use of this
677 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
678 shell installer script}. The script automates the download, installation, and
679 initial configuration steps described below. It should be run as the root
680 user. As root, you can thus run this:
684 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
685 chmod +x guix-install.sh
689 If you're running Debian or a derivative such as Ubuntu, you can instead
690 install the package (it might be a version older than @value{VERSION}
691 but you can update it afterwards by running @samp{guix pull}):
694 sudo apt install guix
697 Likewise on openSUSE:
700 sudo zypper install guix
703 When you're done, @pxref{Application Setup} for extra configuration you
704 might need, and @ref{Getting Started} for your first steps!
707 Installing goes along these lines:
711 @cindex downloading Guix binary
712 Download the binary tarball from
713 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
714 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
715 @code{i686} (32-bits) machine already running the kernel Linux, and so on
716 (@pxref{GNU Distribution}).
718 @c The following is somewhat duplicated in ``System Installation''.
719 Make sure to download the associated @file{.sig} file and to verify the
720 authenticity of the tarball against it, along these lines:
723 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
724 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
727 If that command fails because you do not have the required public key,
728 then run this command to import it:
731 $ wget '@value{OPENPGP-SIGNING-KEY-URL}' \
732 -qO - | gpg --import -
736 and rerun the @code{gpg --verify} command.
738 Take note that a warning like ``This key is not certified with a trusted
739 signature!'' is normal.
741 @c end authentication part
744 Now, you need to become the @code{root} user. Depending on your distribution,
745 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
749 # tar --warning=no-timestamp -xf \
750 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
751 # mv var/guix /var/ && mv gnu /
754 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
755 The latter contains a ready-to-use profile for @code{root} (see next
758 Do @emph{not} unpack the tarball on a working Guix system since that
759 would overwrite its own essential files.
761 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
762 not emit warnings about ``implausibly old time stamps'' (such
763 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
765 They stem from the fact that all the
766 files in the archive have their modification time set to 1 (which
767 means January 1st, 1970). This is done on purpose to make sure the
768 archive content is independent of its creation time, thus making it
772 Make the profile available under @file{~root/.config/guix/current}, which is
773 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
776 # mkdir -p ~root/.config/guix
777 # ln -sf /var/guix/profiles/per-user/root/current-guix \
778 ~root/.config/guix/current
781 Source @file{etc/profile} to augment @env{PATH} and other relevant
782 environment variables:
785 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
786 source $GUIX_PROFILE/etc/profile
790 Create the group and user accounts for build users as explained below
791 (@pxref{Build Environment Setup}).
794 Run the daemon, and set it to automatically start on boot.
796 If your host distro uses the systemd init system, this can be achieved
799 @c Versions of systemd that supported symlinked service files are not
800 @c yet widely deployed, so we should suggest that users copy the service
803 @c See this thread for more information:
804 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
807 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
808 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
810 # systemctl enable --now gnu-store.mount guix-daemon
813 You may also want to arrange for @command{guix gc} to run periodically:
816 # cp ~root/.config/guix/current/lib/systemd/system/guix-gc.service \
817 ~root/.config/guix/current/lib/systemd/system/guix-gc.timer \
819 # systemctl enable --now guix-gc.timer
822 You may want to edit @file{guix-gc.service} to adjust the command line
823 options to fit your needs (@pxref{Invoking guix gc}).
825 If your host distro uses the Upstart init system:
828 # initctl reload-configuration
829 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
834 Otherwise, you can still start the daemon manually with:
837 # ~root/.config/guix/current/bin/guix-daemon \
838 --build-users-group=guixbuild
842 Make the @command{guix} command available to other users on the machine,
846 # mkdir -p /usr/local/bin
848 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
851 It is also a good idea to make the Info version of this manual available
855 # mkdir -p /usr/local/share/info
856 # cd /usr/local/share/info
857 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
861 That way, assuming @file{/usr/local/share/info} is in the search path,
862 running @command{info guix} will open this manual (@pxref{Other Info
863 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
867 @cindex substitutes, authorization thereof
868 To use substitutes from @code{@value{SUBSTITUTE-SERVER-1}},
869 @code{@value{SUBSTITUTE-SERVER-2}} or a mirror (@pxref{Substitutes}),
873 # guix archive --authorize < \
874 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
875 # guix archive --authorize < \
876 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
880 If you do not enable substitutes, Guix will end up building
881 @emph{everything} from source on your machine, making each installation
882 and upgrade very expensive. @xref{On Trusting Binaries}, for a
883 discussion of reasons why one might want do disable substitutes.
887 Each user may need to perform a few additional steps to make their Guix
888 environment ready for use, @pxref{Application Setup}.
891 Voilà, the installation is complete!
893 You can confirm that Guix is working by installing a sample package into
900 The binary installation tarball can be (re)produced and verified simply
901 by running the following command in the Guix source tree:
904 make guix-binary.@var{system}.tar.xz
908 ...@: which, in turn, runs:
911 guix pack -s @var{system} --localstatedir \
912 --profile-name=current-guix guix
915 @xref{Invoking guix pack}, for more info on this handy tool.
918 @section Requirements
920 This section lists requirements when building Guix from source. The
921 build procedure for Guix is the same as for other GNU software, and is
922 not covered here. Please see the files @file{README} and @file{INSTALL}
923 in the Guix source tree for additional details.
925 @cindex official website
926 GNU Guix is available for download from its website at
927 @url{https://www.gnu.org/software/guix/}.
929 GNU Guix depends on the following packages:
932 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x,
933 version 3.0.3 or later;
934 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
937 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
938 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
939 Guile,, gnutls-guile, GnuTLS-Guile});
941 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
943 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib},
944 version 0.1.0 or later;
945 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
946 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
948 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.5.0
950 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
952 @item @url{https://www.gnu.org/software/make/, GNU Make}.
955 The following dependencies are optional:
959 @c Note: We need at least 0.13.0 for #:nodelay.
960 Support for build offloading (@pxref{Daemon Offload Setup}) and
961 @command{guix copy} (@pxref{Invoking guix copy}) depends on
962 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
963 version 0.13.0 or later.
966 @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
967 compression and decompression in @command{guix publish} and for
968 substitutes (@pxref{Invoking guix publish}).
971 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
972 the @code{crate} importer (@pxref{Invoking guix import}).
975 @uref{https://www.nongnu.org/guile-lib/doc/ref/htmlprag/, Guile-Lib} for
976 the @code{go} importer (@pxref{Invoking guix import}) and for some of
977 the ``updaters'' (@pxref{Invoking guix refresh}).
980 When @url{http://www.bzip.org, libbz2} is available,
981 @command{guix-daemon} can use it to compress build logs.
984 Unless @option{--disable-daemon} was passed to @command{configure}, the
985 following packages are also needed:
988 @item @url{https://gnupg.org/, GNU libgcrypt};
989 @item @url{https://sqlite.org, SQLite 3};
990 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
994 @cindex state directory
995 When configuring Guix on a system that already has a Guix installation,
996 be sure to specify the same state directory as the existing installation
997 using the @option{--localstatedir} option of the @command{configure}
998 script (@pxref{Directory Variables, @code{localstatedir},, standards,
999 GNU Coding Standards}). Usually, this @var{localstatedir} option is
1000 set to the value @file{/var}. The @command{configure} script protects
1001 against unintended misconfiguration of @var{localstatedir} so you do not
1002 inadvertently corrupt your store (@pxref{The Store}).
1004 @node Running the Test Suite
1005 @section Running the Test Suite
1008 After a successful @command{configure} and @code{make} run, it is a good
1009 idea to run the test suite. It can help catch issues with the setup or
1010 environment, or bugs in Guix itself---and really, reporting test
1011 failures is a good way to help improve the software. To run the test
1018 Test cases can run in parallel: you can use the @code{-j} option of
1019 GNU@tie{}make to speed things up. The first run may take a few minutes
1020 on a recent machine; subsequent runs will be faster because the store
1021 that is created for test purposes will already have various things in
1024 It is also possible to run a subset of the tests by defining the
1025 @code{TESTS} makefile variable as in this example:
1028 make check TESTS="tests/store.scm tests/cpio.scm"
1031 By default, tests results are displayed at a file level. In order to
1032 see the details of every individual test cases, it is possible to define
1033 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
1036 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
1039 The underlying SRFI 64 custom Automake test driver used for the 'check'
1040 test suite (located at @file{build-aux/test-driver.scm}) also allows
1041 selecting which test cases to run at a finer level, via its
1042 @option{--select} and @option{--exclude} options. Here's an example, to
1043 run all the test cases from the @file{tests/packages.scm} test file
1044 whose names start with ``transaction-upgrade-entry'':
1047 export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
1048 make check TESTS="tests/packages.scm"
1051 Those wishing to inspect the results of failed tests directly from the
1052 command line can add the @option{--errors-only=yes} option to the
1053 @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
1054 Automake makefile variable, as in:
1057 make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
1060 The @option{--show-duration=yes} option can be used to print the
1061 duration of the individual test cases, when used in combination with
1062 @option{--brief=no}:
1065 make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
1068 @xref{Parallel Test Harness,,,automake,GNU Automake} for more
1069 information about the Automake Parallel Test Harness.
1071 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
1072 @file{test-suite.log} file. Please specify the Guix version being used
1073 as well as version numbers of the dependencies (@pxref{Requirements}) in
1076 Guix also comes with a whole-system test suite that tests complete
1077 Guix System instances. It can only run on systems where
1078 Guix is already installed, using:
1085 or, again, by defining @code{TESTS} to select a subset of tests to run:
1088 make check-system TESTS="basic mcron"
1091 These system tests are defined in the @code{(gnu tests @dots{})}
1092 modules. They work by running the operating systems under test with
1093 lightweight instrumentation in a virtual machine (VM). They can be
1094 computationally intensive or rather cheap, depending on whether
1095 substitutes are available for their dependencies (@pxref{Substitutes}).
1096 Some of them require a lot of storage space to hold VM images.
1098 Again in case of test failures, please send @email{bug-guix@@gnu.org}
1101 @node Setting Up the Daemon
1102 @section Setting Up the Daemon
1105 Operations such as building a package or running the garbage collector
1106 are all performed by a specialized process, the @dfn{build daemon}, on
1107 behalf of clients. Only the daemon may access the store and its
1108 associated database. Thus, any operation that manipulates the store
1109 goes through the daemon. For instance, command-line tools such as
1110 @command{guix package} and @command{guix build} communicate with the
1111 daemon (@i{via} remote procedure calls) to instruct it what to do.
1113 The following sections explain how to prepare the build daemon's
1114 environment. See also @ref{Substitutes}, for information on how to allow
1115 the daemon to download pre-built binaries.
1118 * Build Environment Setup:: Preparing the isolated build environment.
1119 * Daemon Offload Setup:: Offloading builds to remote machines.
1120 * SELinux Support:: Using an SELinux policy for the daemon.
1123 @node Build Environment Setup
1124 @subsection Build Environment Setup
1126 @cindex build environment
1127 In a standard multi-user setup, Guix and its daemon---the
1128 @command{guix-daemon} program---are installed by the system
1129 administrator; @file{/gnu/store} is owned by @code{root} and
1130 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
1131 Guix tools to build packages or otherwise access the store, and the
1132 daemon will do it on their behalf, ensuring that the store is kept in a
1133 consistent state, and allowing built packages to be shared among users.
1136 When @command{guix-daemon} runs as @code{root}, you may not want package
1137 build processes themselves to run as @code{root} too, for obvious
1138 security reasons. To avoid that, a special pool of @dfn{build users}
1139 should be created for use by build processes started by the daemon.
1140 These build users need not have a shell and a home directory: they will
1141 just be used when the daemon drops @code{root} privileges in build
1142 processes. Having several such users allows the daemon to launch
1143 distinct build processes under separate UIDs, which guarantees that they
1144 do not interfere with each other---an essential feature since builds are
1145 regarded as pure functions (@pxref{Introduction}).
1147 On a GNU/Linux system, a build user pool may be created like this (using
1148 Bash syntax and the @code{shadow} commands):
1150 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
1151 @c for why `-G' is needed.
1153 # groupadd --system guixbuild
1154 # for i in $(seq -w 1 10);
1156 useradd -g guixbuild -G guixbuild \
1157 -d /var/empty -s $(which nologin) \
1158 -c "Guix build user $i" --system \
1164 The number of build users determines how many build jobs may run in
1165 parallel, as specified by the @option{--max-jobs} option
1166 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1167 @command{guix system vm} and related commands, you may need to add the
1168 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1169 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1170 (@pxref{Invoking guix system}).
1172 The @code{guix-daemon} program may then be run as @code{root} with the
1173 following command@footnote{If your machine uses the systemd init system,
1174 copying the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1175 file to @file{/etc/systemd/system} will ensure that
1176 @command{guix-daemon} is automatically started. Similarly, if your
1177 machine uses the Upstart init system, copy the
1178 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1179 file to @file{/etc/init}.}:
1182 # guix-daemon --build-users-group=guixbuild
1187 This way, the daemon starts build processes in a chroot, under one of
1188 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1189 environment contains nothing but:
1191 @c Keep this list in sync with libstore/build.cc! -----------------------
1194 a minimal @code{/dev} directory, created mostly independently from the
1195 host @code{/dev}@footnote{``Mostly'', because while the set of files
1196 that appear in the chroot's @code{/dev} is fixed, most of these files
1197 can only be created if the host has them.};
1200 the @code{/proc} directory; it only shows the processes of the container
1201 since a separate PID name space is used;
1204 @file{/etc/passwd} with an entry for the current user and an entry for
1208 @file{/etc/group} with an entry for the user's group;
1211 @file{/etc/hosts} with an entry that maps @code{localhost} to
1215 a writable @file{/tmp} directory.
1218 The chroot does not contain a @file{/home} directory, and the @env{HOME}
1219 environment variable is set to the non-existent
1220 @file{/homeless-shelter}. This helps to highlight inappropriate uses of
1221 @env{HOME} in the build scripts of packages.
1223 You can influence the directory where the daemon stores build trees
1224 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1225 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1226 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1227 This way, the value of @env{TMPDIR} does not leak inside build
1228 environments, which avoids discrepancies in cases where build processes
1229 capture the name of their build tree.
1233 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1234 environment variables for HTTP and HTTPS downloads it performs, be it
1235 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1236 (@pxref{Substitutes}).
1238 If you are installing Guix as an unprivileged user, it is still possible
1239 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1240 However, build processes will not be isolated from one another, and not
1241 from the rest of the system. Thus, build processes may interfere with
1242 each other, and may access programs, libraries, and other files
1243 available on the system---making it much harder to view them as
1244 @emph{pure} functions.
1247 @node Daemon Offload Setup
1248 @subsection Using the Offload Facility
1252 When desired, the build daemon can @dfn{offload} derivation builds to
1253 other machines running Guix, using the @code{offload} @dfn{build
1254 hook}@footnote{This feature is available only when
1255 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1256 present.}. When that feature is enabled, a list of user-specified build
1257 machines is read from @file{/etc/guix/machines.scm}; every time a build
1258 is requested, for instance via @code{guix build}, the daemon attempts to
1259 offload it to one of the machines that satisfy the constraints of the
1260 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1261 A single machine can have multiple system types, either because its
1262 architecture natively supports it, via emulation
1263 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1264 or both. Missing prerequisites for the build are
1265 copied over SSH to the target machine, which then proceeds with the
1266 build; upon success the output(s) of the build are copied back to the
1267 initial machine. The offload facility comes with a basic scheduler that
1268 attempts to select the best machine. The best machine is chosen among
1269 the available machines based on criteria such as:
1273 The availability of a build slot. A build machine can have as many
1274 build slots (connections) as the value of the @code{parallel-builds}
1275 field of its @code{build-machine} object.
1278 Its relative speed, as defined via the @code{speed} field of its
1279 @code{build-machine} object.
1282 Its load. The normalized machine load must be lower than a threshold
1283 value, configurable via the @code{overload-threshold} field of its
1284 @code{build-machine} object.
1287 Disk space availability. More than a 100 MiB must be available.
1290 The @file{/etc/guix/machines.scm} file typically looks like this:
1293 (list (build-machine
1294 (name "eightysix.example.org")
1295 (systems (list "x86_64-linux" "i686-linux"))
1296 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1298 (speed 2.)) ;incredibly fast!
1301 (name "armeight.example.org")
1302 (systems (list "aarch64-linux"))
1303 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1306 ;; Remember 'guix offload' is spawned by
1307 ;; 'guix-daemon' as root.
1308 (private-key "/root/.ssh/identity-for-guix")))
1312 In the example above we specify a list of two build machines, one for
1313 the @code{x86_64} and @code{i686} architectures and one for the
1314 @code{aarch64} architecture.
1316 In fact, this file is---not surprisingly!---a Scheme file that is
1317 evaluated when the @code{offload} hook is started. Its return value
1318 must be a list of @code{build-machine} objects. While this example
1319 shows a fixed list of build machines, one could imagine, say, using
1320 DNS-SD to return a list of potential build machines discovered in the
1321 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1322 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1325 @deftp {Data Type} build-machine
1326 This data type represents build machines to which the daemon may offload
1327 builds. The important fields are:
1332 The host name of the remote machine.
1335 The system types the remote machine supports---e.g., @code{(list
1336 "x86_64-linux" "i686-linux")}.
1339 The user account to use when connecting to the remote machine over SSH.
1340 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1341 allow non-interactive logins.
1344 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1345 This is used to authenticate the machine when we connect to it. It is a
1346 long string that looks like this:
1349 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1352 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1353 key can be found in a file such as
1354 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1356 If the machine is running the SSH daemon of GNU@tie{}lsh,
1357 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1358 similar file. It can be converted to the OpenSSH format using
1359 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1362 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1363 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1368 A number of optional fields may be specified:
1372 @item @code{port} (default: @code{22})
1373 Port number of SSH server on the machine.
1375 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1376 The SSH private key file to use when connecting to the machine, in
1377 OpenSSH format. This key must not be protected with a passphrase.
1379 Note that the default value is the private key @emph{of the root
1380 account}. Make sure it exists if you use the default.
1382 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1383 @itemx @code{compression-level} (default: @code{3})
1384 The SSH-level compression methods and compression level requested.
1386 Note that offloading relies on SSH compression to reduce bandwidth usage
1387 when transferring files to and from build machines.
1389 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1390 File name of the Unix-domain socket @command{guix-daemon} is listening
1393 @item @code{overload-threshold} (default: @code{0.6})
1394 The load threshold above which a potential offload machine is
1395 disregarded by the offload scheduler. The value roughly translates to
1396 the total processor usage of the build machine, ranging from 0.0 (0%) to
1397 1.0 (100%). It can also be disabled by setting
1398 @code{overload-threshold} to @code{#f}.
1400 @item @code{parallel-builds} (default: @code{1})
1401 The number of builds that may run in parallel on the machine.
1403 @item @code{speed} (default: @code{1.0})
1404 A ``relative speed factor''. The offload scheduler will tend to prefer
1405 machines with a higher speed factor.
1407 @item @code{features} (default: @code{'()})
1408 A list of strings denoting specific features supported by the machine.
1409 An example is @code{"kvm"} for machines that have the KVM Linux modules
1410 and corresponding hardware support. Derivations can request features by
1411 name, and they will be scheduled on matching build machines.
1416 The @command{guix} command must be in the search path on the build
1417 machines. You can check whether this is the case by running:
1420 ssh build-machine guix repl --version
1423 There is one last thing to do once @file{machines.scm} is in place. As
1424 explained above, when offloading, files are transferred back and forth
1425 between the machine stores. For this to work, you first need to
1426 generate a key pair on each machine to allow the daemon to export signed
1427 archives of files from the store (@pxref{Invoking guix archive}):
1430 # guix archive --generate-key
1434 Each build machine must authorize the key of the master machine so that
1435 it accepts store items it receives from the master:
1438 # guix archive --authorize < master-public-key.txt
1442 Likewise, the master machine must authorize the key of each build machine.
1444 All the fuss with keys is here to express pairwise mutual trust
1445 relations between the master and the build machines. Concretely, when
1446 the master receives files from a build machine (and @i{vice versa}), its
1447 build daemon can make sure they are genuine, have not been tampered
1448 with, and that they are signed by an authorized key.
1450 @cindex offload test
1451 To test whether your setup is operational, run this command on the
1458 This will attempt to connect to each of the build machines specified in
1459 @file{/etc/guix/machines.scm}, make sure Guix is
1460 available on each machine, attempt to export to the machine and import
1461 from it, and report any error in the process.
1463 If you want to test a different machine file, just specify it on the
1467 # guix offload test machines-qualif.scm
1470 Last, you can test the subset of the machines whose name matches a
1471 regular expression like this:
1474 # guix offload test machines.scm '\.gnu\.org$'
1477 @cindex offload status
1478 To display the current load of all build hosts, run this command on the
1482 # guix offload status
1486 @node SELinux Support
1487 @subsection SELinux Support
1489 @cindex SELinux, daemon policy
1490 @cindex mandatory access control, SELinux
1491 @cindex security, guix-daemon
1492 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1493 can be installed on a system where SELinux is enabled, in order to label
1494 Guix files and to specify the expected behavior of the daemon. Since
1495 Guix System does not provide an SELinux base policy, the daemon policy cannot
1496 be used on Guix System.
1498 @subsubsection Installing the SELinux policy
1499 @cindex SELinux, policy installation
1500 To install the policy run this command as root:
1503 semodule -i etc/guix-daemon.cil
1506 Then relabel the file system with @code{restorecon} or by a different
1507 mechanism provided by your system.
1509 Once the policy is installed, the file system has been relabeled, and
1510 the daemon has been restarted, it should be running in the
1511 @code{guix_daemon_t} context. You can confirm this with the following
1515 ps -Zax | grep guix-daemon
1518 Monitor the SELinux log files as you run a command like @code{guix build
1519 hello} to convince yourself that SELinux permits all necessary
1522 @subsubsection Limitations
1523 @cindex SELinux, limitations
1525 This policy is not perfect. Here is a list of limitations or quirks
1526 that should be considered when deploying the provided SELinux policy for
1531 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1532 operations involve contexts that have anything to do with
1533 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1534 but it would be preferable to define socket rules for only this label.
1537 @code{guix gc} cannot access arbitrary links to profiles. By design,
1538 the file label of the destination of a symlink is independent of the
1539 file label of the link itself. Although all profiles under
1540 $localstatedir are labelled, the links to these profiles inherit the
1541 label of the directory they are in. For links in the user’s home
1542 directory this will be @code{user_home_t}. But for links from the root
1543 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1544 directory, etc, this won’t work. @code{guix gc} would be prevented from
1545 reading and following these links.
1548 The daemon’s feature to listen for TCP connections might no longer work.
1549 This might require extra rules, because SELinux treats network sockets
1550 differently from files.
1553 Currently all files with a name matching the regular expression
1554 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1555 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1556 that name in any profile would be permitted to run in the
1557 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1558 build a package that provides this executable and convince a user to
1559 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1560 At that point SELinux could not prevent it from accessing files that are
1561 allowed for processes in that domain.
1563 You will need to relabel the store directory after all upgrades to
1564 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1565 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1566 or by other means provided by your operating system.
1568 We could generate a much more restrictive policy at installation time,
1569 so that only the @emph{exact} file name of the currently installed
1570 @code{guix-daemon} executable would be labelled with
1571 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1572 The downside is that root would have to install or upgrade the policy at
1573 installation time whenever the Guix package that provides the
1574 effectively running @code{guix-daemon} executable is upgraded.
1577 @node Invoking guix-daemon
1578 @section Invoking @command{guix-daemon}
1580 The @command{guix-daemon} program implements all the functionality to
1581 access the store. This includes launching build processes, running the
1582 garbage collector, querying the availability of a build result, etc. It
1583 is normally run as @code{root} like this:
1586 # guix-daemon --build-users-group=guixbuild
1589 @cindex socket activation, for @command{guix-daemon}
1590 This daemon can also be started following the systemd ``socket
1591 activation'' protocol (@pxref{Service De- and Constructors,
1592 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
1594 For details on how to set it up, @pxref{Setting Up the Daemon}.
1597 @cindex container, build environment
1598 @cindex build environment
1599 @cindex reproducible builds
1600 By default, @command{guix-daemon} launches build processes under
1601 different UIDs, taken from the build group specified with
1602 @option{--build-users-group}. In addition, each build process is run in a
1603 chroot environment that only contains the subset of the store that the
1604 build process depends on, as specified by its derivation
1605 (@pxref{Programming Interface, derivation}), plus a set of specific
1606 system directories. By default, the latter contains @file{/dev} and
1607 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1608 @dfn{container}: in addition to having its own file system tree, it has
1609 a separate mount name space, its own PID name space, network name space,
1610 etc. This helps achieve reproducible builds (@pxref{Features}).
1612 When the daemon performs a build on behalf of the user, it creates a
1613 build directory under @file{/tmp} or under the directory specified by
1614 its @env{TMPDIR} environment variable. This directory is shared with
1615 the container for the duration of the build, though within the container,
1616 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1618 The build directory is automatically deleted upon completion, unless the
1619 build failed and the client specified @option{--keep-failed}
1620 (@pxref{Common Build Options, @option{--keep-failed}}).
1622 The daemon listens for connections and spawns one sub-process for each session
1623 started by a client (one of the @command{guix} sub-commands). The
1624 @command{guix processes} command allows you to get an overview of the activity
1625 on your system by viewing each of the active sessions and clients.
1626 @xref{Invoking guix processes}, for more information.
1628 The following command-line options are supported:
1631 @item --build-users-group=@var{group}
1632 Take users from @var{group} to run build processes (@pxref{Setting Up
1633 the Daemon, build users}).
1635 @item --no-substitutes
1637 Do not use substitutes for build products. That is, always build things
1638 locally instead of allowing downloads of pre-built binaries
1639 (@pxref{Substitutes}).
1641 When the daemon runs with @option{--no-substitutes}, clients can still
1642 explicitly enable substitution @i{via} the @code{set-build-options}
1643 remote procedure call (@pxref{The Store}).
1645 @anchor{daemon-substitute-urls}
1646 @item --substitute-urls=@var{urls}
1647 Consider @var{urls} the default whitespace-separated list of substitute
1648 source URLs. When this option is omitted,
1649 @indicateurl{@value{SUBSTITUTE-URLS}} is used.
1651 This means that substitutes may be downloaded from @var{urls}, as long
1652 as they are signed by a trusted signature (@pxref{Substitutes}).
1654 @xref{Getting Substitutes from Other Servers}, for more information on
1655 how to configure the daemon to get substitutes from other servers.
1659 Do not use offload builds to other machines (@pxref{Daemon Offload
1660 Setup}). That is, always build things locally instead of offloading
1661 builds to remote machines.
1663 @item --cache-failures
1664 Cache build failures. By default, only successful builds are cached.
1666 When this option is used, @command{guix gc --list-failures} can be used
1667 to query the set of store items marked as failed; @command{guix gc
1668 --clear-failures} removes store items from the set of cached failures.
1669 @xref{Invoking guix gc}.
1671 @item --cores=@var{n}
1673 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1676 The default value is @code{0}, but it may be overridden by clients, such
1677 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1680 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1681 in the build process, which can then use it to exploit internal
1682 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1684 @item --max-jobs=@var{n}
1686 Allow at most @var{n} build jobs in parallel. The default value is
1687 @code{1}. Setting it to @code{0} means that no builds will be performed
1688 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1689 Setup}), or simply fail.
1691 @item --max-silent-time=@var{seconds}
1692 When the build or substitution process remains silent for more than
1693 @var{seconds}, terminate it and report a build failure.
1695 The default value is @code{0}, which disables the timeout.
1697 The value specified here can be overridden by clients (@pxref{Common
1698 Build Options, @option{--max-silent-time}}).
1700 @item --timeout=@var{seconds}
1701 Likewise, when the build or substitution process lasts for more than
1702 @var{seconds}, terminate it and report a build failure.
1704 The default value is @code{0}, which disables the timeout.
1706 The value specified here can be overridden by clients (@pxref{Common
1707 Build Options, @option{--timeout}}).
1709 @item --rounds=@var{N}
1710 Build each derivation @var{n} times in a row, and raise an error if
1711 consecutive build results are not bit-for-bit identical. Note that this
1712 setting can be overridden by clients such as @command{guix build}
1713 (@pxref{Invoking guix build}).
1715 When used in conjunction with @option{--keep-failed}, the differing
1716 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1717 This makes it easy to look for differences between the two results.
1720 Produce debugging output.
1722 This is useful to debug daemon start-up issues, but then it may be
1723 overridden by clients, for example the @option{--verbosity} option of
1724 @command{guix build} (@pxref{Invoking guix build}).
1726 @item --chroot-directory=@var{dir}
1727 Add @var{dir} to the build chroot.
1729 Doing this may change the result of build processes---for instance if
1730 they use optional dependencies found in @var{dir} when it is available,
1731 and not otherwise. For that reason, it is not recommended to do so.
1732 Instead, make sure that each derivation declares all the inputs that it
1735 @item --disable-chroot
1736 Disable chroot builds.
1738 Using this option is not recommended since, again, it would allow build
1739 processes to gain access to undeclared dependencies. It is necessary,
1740 though, when @command{guix-daemon} is running under an unprivileged user
1743 @item --log-compression=@var{type}
1744 Compress build logs according to @var{type}, one of @code{gzip},
1745 @code{bzip2}, or @code{none}.
1747 Unless @option{--lose-logs} is used, all the build logs are kept in the
1748 @var{localstatedir}. To save space, the daemon automatically compresses
1749 them with gzip by default.
1751 @item --discover[=yes|no]
1752 Whether to discover substitute servers on the local network using mDNS
1755 This feature is still experimental. However, here are a few
1760 It might be faster/less expensive than fetching from remote servers;
1762 There are no security risks, only genuine substitutes will be used
1763 (@pxref{Substitute Authentication});
1765 An attacker advertising @command{guix publish} on your LAN cannot serve
1766 you malicious binaries, but they can learn what software you’re
1769 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1770 LAN can see what software you’re installing.
1773 It is also possible to enable or disable substitute server discovery at
1774 run-time by running:
1777 herd discover guix-daemon on
1778 herd discover guix-daemon off
1781 @item --disable-deduplication
1782 @cindex deduplication
1783 Disable automatic file ``deduplication'' in the store.
1785 By default, files added to the store are automatically ``deduplicated'':
1786 if a newly added file is identical to another one found in the store,
1787 the daemon makes the new file a hard link to the other file. This can
1788 noticeably reduce disk usage, at the expense of slightly increased
1789 input/output load at the end of a build process. This option disables
1792 @item --gc-keep-outputs[=yes|no]
1793 Tell whether the garbage collector (GC) must keep outputs of live
1797 @cindex garbage collector roots
1798 When set to @code{yes}, the GC will keep the outputs of any live
1799 derivation available in the store---the @file{.drv} files. The default
1800 is @code{no}, meaning that derivation outputs are kept only if they are
1801 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1804 @item --gc-keep-derivations[=yes|no]
1805 Tell whether the garbage collector (GC) must keep derivations
1806 corresponding to live outputs.
1808 When set to @code{yes}, as is the case by default, the GC keeps
1809 derivations---i.e., @file{.drv} files---as long as at least one of their
1810 outputs is live. This allows users to keep track of the origins of
1811 items in their store. Setting it to @code{no} saves a bit of disk
1814 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1815 liveness to flow from outputs to derivations, and setting
1816 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1817 derivations to outputs. When both are set to @code{yes}, the effect is
1818 to keep all the build prerequisites (the sources, compiler, libraries,
1819 and other build-time tools) of live objects in the store, regardless of
1820 whether these prerequisites are reachable from a GC root. This is
1821 convenient for developers since it saves rebuilds or downloads.
1823 @item --impersonate-linux-2.6
1824 On Linux-based systems, impersonate Linux 2.6. This means that the
1825 kernel's @command{uname} system call will report 2.6 as the release number.
1827 This might be helpful to build programs that (usually wrongfully) depend
1828 on the kernel version number.
1831 Do not keep build logs. By default they are kept under
1832 @file{@var{localstatedir}/guix/log}.
1834 @item --system=@var{system}
1835 Assume @var{system} as the current system type. By default it is the
1836 architecture/kernel pair found at configure time, such as
1837 @code{x86_64-linux}.
1839 @item --listen=@var{endpoint}
1840 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1841 as the file name of a Unix-domain socket if it starts with
1842 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1843 host name or host name and port to listen to. Here are a few examples:
1846 @item --listen=/gnu/var/daemon
1847 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1848 creating it if needed.
1850 @item --listen=localhost
1851 @cindex daemon, remote access
1852 @cindex remote access to the daemon
1853 @cindex daemon, cluster setup
1854 @cindex clusters, daemon setup
1855 Listen for TCP connections on the network interface corresponding to
1856 @code{localhost}, on port 44146.
1858 @item --listen=128.0.0.42:1234
1859 Listen for TCP connections on the network interface corresponding to
1860 @code{128.0.0.42}, on port 1234.
1863 This option can be repeated multiple times, in which case
1864 @command{guix-daemon} accepts connections on all the specified
1865 endpoints. Users can tell client commands what endpoint to connect to
1866 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1867 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1870 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1871 @option{--listen=@var{host}} is suitable on local networks, such as
1872 clusters, where only trusted nodes may connect to the build daemon. In
1873 other cases where remote access to the daemon is needed, we recommend
1874 using Unix-domain sockets along with SSH.
1877 When @option{--listen} is omitted, @command{guix-daemon} listens for
1878 connections on the Unix-domain socket located at
1879 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1883 @node Application Setup
1884 @section Application Setup
1886 @cindex foreign distro
1887 When using Guix on top of GNU/Linux distribution other than Guix System---a
1888 so-called @dfn{foreign distro}---a few additional steps are needed to
1889 get everything in place. Here are some of them.
1893 @anchor{locales-and-locpath}
1894 @cindex locales, when not on Guix System
1896 @vindex GUIX_LOCPATH
1897 Packages installed @i{via} Guix will not use the locale data of the
1898 host system. Instead, you must first install one of the locale packages
1899 available with Guix and then define the @env{GUIX_LOCPATH} environment
1903 $ guix install glibc-locales
1904 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1907 Note that the @code{glibc-locales} package contains data for all the
1908 locales supported by the GNU@tie{}libc and weighs in at around
1909 930@tie{}MiB@footnote{The size of the @code{glibc-locales} package is
1910 reduced down to about 213@tie{}MiB with store deduplication and further
1911 down to about 67@tie{}MiB when using a zstd-compressed Btrfs file
1912 system.}. If you only need a few locales, you can define your custom
1913 locales package via the @code{make-glibc-utf8-locales} procedure from
1914 the @code{(gnu packages base)} module. The following example defines a
1915 package containing the various Canadian UTF-8 locales known to the
1916 GNU@tie{}libc, that weighs around 14@tie{}MiB:
1919 (use-modules (gnu packages base))
1921 (define my-glibc-locales
1922 (make-glibc-utf8-locales
1924 #:locales (list "en_CA" "fr_CA" "ik_CA" "iu_CA" "shs_CA")
1925 #:name "glibc-canadian-utf8-locales"))
1928 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1929 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1930 Manual}). There are two important differences though:
1934 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1935 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1936 to make sure the programs of the foreign distro will not end up loading
1937 incompatible locale data.
1940 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1941 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1942 should your Guix profile contain a mixture of programs linked against
1943 different libc version, each libc version will only try to load locale
1944 data in the right format.
1947 This is important because the locale data format used by different libc
1948 versions may be incompatible.
1950 @subsection Name Service Switch
1952 @cindex name service switch, glibc
1953 @cindex NSS (name service switch), glibc
1954 @cindex nscd (name service caching daemon)
1955 @cindex name service caching daemon (nscd)
1956 When using Guix on a foreign distro, we @emph{strongly recommend} that
1957 the system run the GNU C library's @dfn{name service cache daemon},
1958 @command{nscd}, which should be listening on the
1959 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1960 installed with Guix may fail to look up host names or user accounts, or
1961 may even crash. The next paragraphs explain why.
1963 @cindex @file{nsswitch.conf}
1964 The GNU C library implements a @dfn{name service switch} (NSS), which is
1965 an extensible mechanism for ``name lookups'' in general: host name
1966 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1967 The GNU C Library Reference Manual}).
1969 @cindex Network information service (NIS)
1970 @cindex NIS (Network information service)
1971 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1972 lookup implementations: for example, the @code{nss-mdns} plugin allow
1973 resolution of @code{.local} host names, the @code{nis} plugin allows
1974 user account lookup using the Network information service (NIS), and so
1975 on. These extra ``lookup services'' are configured system-wide in
1976 @file{/etc/nsswitch.conf}, and all the programs running on the system
1977 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1980 When they perform a name lookup---for instance by calling the
1981 @code{getaddrinfo} function in C---applications first try to connect to
1982 the nscd; on success, nscd performs name lookups on their behalf. If
1983 the nscd is not running, then they perform the name lookup by
1984 themselves, by loading the name lookup services into their own address
1985 space and running it. These name lookup services---the
1986 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1987 the host system's C library, rather than from the C library the
1988 application is linked against (the C library coming from Guix).
1990 And this is where the problem is: if your application is linked against
1991 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1992 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1993 likely crash or have its name lookups fail unexpectedly.
1995 Running @command{nscd} on the system, among other advantages, eliminates
1996 this binary incompatibility problem because those @code{libnss_*.so}
1997 files are loaded in the @command{nscd} process, not in applications
2000 @subsection X11 Fonts
2003 The majority of graphical applications use Fontconfig to locate and load
2004 fonts and perform X11-client-side rendering. The @code{fontconfig}
2005 package in Guix looks for fonts in @file{$HOME/.guix-profile} by
2006 default. Thus, to allow graphical applications installed with Guix to
2007 display fonts, you have to install fonts with Guix as well. Essential
2008 font packages include @code{font-ghostscript}, @code{font-dejavu}, and
2009 @code{font-gnu-freefont}.
2011 @cindex @code{fc-cache}
2013 Once you have installed or removed fonts, or when you notice an
2014 application that does not find fonts, you may need to install Fontconfig
2015 and to force an update of its font cache by running:
2018 guix install fontconfig
2022 To display text written in Chinese languages, Japanese, or Korean in
2023 graphical applications, consider installing
2024 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
2025 has multiple outputs, one per language family (@pxref{Packages with
2026 Multiple Outputs}). For instance, the following command installs fonts
2027 for Chinese languages:
2030 guix install font-adobe-source-han-sans:cn
2033 @cindex @code{xterm}
2034 Older programs such as @command{xterm} do not use Fontconfig and instead
2035 rely on server-side font rendering. Such programs require to specify a
2036 full name of a font using XLFD (X Logical Font Description), like this:
2039 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
2042 To be able to use such full names for the TrueType fonts installed in
2043 your Guix profile, you need to extend the font path of the X server:
2045 @c Note: 'xset' does not accept symlinks so the trick below arranges to
2046 @c get at the real directory. See <https://bugs.gnu.org/30655>.
2048 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
2051 @cindex @code{xlsfonts}
2052 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
2053 to make sure your TrueType fonts are listed there.
2056 @subsection X.509 Certificates
2058 @cindex @code{nss-certs}
2059 The @code{nss-certs} package provides X.509 certificates, which allow
2060 programs to authenticate Web servers accessed over HTTPS.
2062 When using Guix on a foreign distro, you can install this package and
2063 define the relevant environment variables so that packages know where to
2064 look for certificates. @xref{X.509 Certificates}, for detailed
2067 @subsection Emacs Packages
2069 @cindex @code{emacs}
2070 When you install Emacs packages with Guix, the Elisp files are placed
2071 under the @file{share/emacs/site-lisp/} directory of the profile in
2072 which they are installed. The Elisp libraries are made available to
2073 Emacs through the @env{EMACSLOADPATH} environment variable, which is
2074 set when installing Emacs itself.
2076 Additionally, autoload definitions are automatically evaluated at the
2077 initialization of Emacs, by the Guix-specific
2078 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
2079 want to avoid auto-loading the Emacs packages installed with Guix, you
2080 can do so by running Emacs with the @option{--no-site-file} option
2081 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
2084 @node Upgrading Guix
2085 @section Upgrading Guix
2087 @cindex Upgrading Guix, on a foreign distro
2089 To upgrade Guix, run:
2095 @xref{Invoking guix pull}, for more information.
2097 @cindex upgrading Guix for the root user, on a foreign distro
2098 @cindex upgrading the Guix daemon, on a foreign distro
2099 @cindex @command{guix pull} for the root user, on a foreign distro
2101 On a foreign distro, you can upgrade the build daemon by running:
2108 followed by (assuming your distro uses the systemd service management
2112 systemctl restart guix-daemon.service
2115 On Guix System, upgrading the daemon is achieved by reconfiguring the
2116 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
2120 @c *********************************************************************
2121 @node System Installation
2122 @chapter System Installation
2124 @cindex installing Guix System
2125 @cindex Guix System, installation
2126 This section explains how to install Guix System
2127 on a machine. Guix, as a package manager, can
2128 also be installed on top of a running GNU/Linux system,
2129 @pxref{Installation}.
2133 @c This paragraph is for people reading this from tty2 of the
2134 @c installation image.
2135 You are reading this documentation with an Info reader. For details on
2136 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
2137 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
2138 Info}. Hit @kbd{l} afterwards to come back here.
2140 Alternatively, run @command{info info} in another tty to keep the manual
2146 * Limitations:: What you can expect.
2147 * Hardware Considerations:: Supported hardware.
2148 * USB Stick and DVD Installation:: Preparing the installation medium.
2149 * Preparing for Installation:: Networking, partitioning, etc.
2150 * Guided Graphical Installation:: Easy graphical installation.
2151 * Manual Installation:: Manual installation for wizards.
2152 * After System Installation:: When installation succeeded.
2153 * Installing Guix in a VM:: Guix System playground.
2154 * Building the Installation Image:: How this comes to be.
2158 @section Limitations
2160 We consider Guix System to be ready for a wide range of ``desktop'' and server
2161 use cases. The reliability guarantees it provides---transactional upgrades
2162 and rollbacks, reproducibility---make it a solid foundation.
2164 Nevertheless, before you proceed with the installation, be aware of the
2165 following noteworthy limitations applicable to version @value{VERSION}:
2169 More and more system services are provided (@pxref{Services}), but some
2173 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
2174 as well as a number of X11 window managers. However, KDE is currently
2178 More than a disclaimer, this is an invitation to report issues (and success
2179 stories!), and to join us in improving it. @xref{Contributing}, for more
2183 @node Hardware Considerations
2184 @section Hardware Considerations
2186 @cindex hardware support on Guix System
2187 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2188 builds around the kernel Linux-libre, which means that only hardware for
2189 which free software drivers and firmware exist is supported. Nowadays,
2190 a wide range of off-the-shelf hardware is supported on
2191 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2192 Ethernet controllers. Unfortunately, there are still areas where
2193 hardware vendors deny users control over their own computing, and such
2194 hardware is not supported on Guix System.
2196 @cindex WiFi, hardware support
2197 One of the main areas where free drivers or firmware are lacking is WiFi
2198 devices. WiFi devices known to work include those using Atheros chips
2199 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2200 driver, and those using Broadcom/AirForce chips (BCM43xx with
2201 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2202 Linux-libre driver. Free firmware exists for both and is available
2203 out-of-the-box on Guix System, as part of @code{%base-firmware}
2204 (@pxref{operating-system Reference, @code{firmware}}).
2206 @cindex RYF, Respects Your Freedom
2207 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2208 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2209 certification program for hardware products that respect your freedom
2210 and your privacy and ensure that you have control over your device. We
2211 encourage you to check the list of RYF-certified devices.
2213 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2214 web site. It contains a catalog of hardware devices with information
2215 about their support in GNU/Linux.
2218 @node USB Stick and DVD Installation
2219 @section USB Stick and DVD Installation
2221 An ISO-9660 installation image that can be written to a USB stick or
2222 burnt to a DVD can be downloaded from
2223 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso},
2224 where you can replace @code{x86_64-linux} with one of:
2228 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2231 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2234 @c start duplication of authentication part from ``Binary Installation''
2235 Make sure to download the associated @file{.sig} file and to verify the
2236 authenticity of the image against it, along these lines:
2239 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2240 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2243 If that command fails because you do not have the required public key,
2244 then run this command to import it:
2247 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2248 -qO - | gpg --import -
2252 and rerun the @code{gpg --verify} command.
2254 Take note that a warning like ``This key is not certified with a trusted
2255 signature!'' is normal.
2259 This image contains the tools necessary for an installation.
2260 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2262 @unnumberedsubsec Copying to a USB Stick
2264 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2265 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2266 copy the image with:
2269 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2273 Access to @file{/dev/sdX} usually requires root privileges.
2275 @unnumberedsubsec Burning on a DVD
2277 Insert a blank DVD into your machine, and determine
2278 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2279 copy the image with:
2282 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2285 Access to @file{/dev/srX} usually requires root privileges.
2287 @unnumberedsubsec Booting
2289 Once this is done, you should be able to reboot the system and boot from
2290 the USB stick or DVD@. The latter usually requires you to get in the
2291 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2292 In order to boot from Libreboot, switch to the command mode by pressing
2293 the @kbd{c} key and type @command{search_grub usb}.
2295 @xref{Installing Guix in a VM}, if, instead, you would like to install
2296 Guix System in a virtual machine (VM).
2299 @node Preparing for Installation
2300 @section Preparing for Installation
2302 Once you have booted, you can use the guided graphical installer, which makes
2303 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2304 if you are already familiar with GNU/Linux and if you want more control than
2305 what the graphical installer provides, you can choose the ``manual''
2306 installation process (@pxref{Manual Installation}).
2308 The graphical installer is available on TTY1. You can obtain root shells on
2309 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2310 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2311 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2312 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2313 which allows you to select text with the left mouse button and to paste it
2314 with the middle button.
2317 Installation requires access to the Internet so that any missing
2318 dependencies of your system configuration can be downloaded. See the
2319 ``Networking'' section below.
2322 @node Guided Graphical Installation
2323 @section Guided Graphical Installation
2325 The graphical installer is a text-based user interface. It will guide you,
2326 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2328 The first dialog boxes allow you to set up the system as you use it during the
2329 installation: you can choose the language, keyboard layout, and set up
2330 networking, which will be used during the installation. The image below shows
2331 the networking dialog.
2333 @image{images/installer-network,5in,, networking setup with the graphical installer}
2335 Later steps allow you to partition your hard disk, as shown in the image
2336 below, to choose whether or not to use encrypted file systems, to enter the
2337 host name and root password, and to create an additional account, among other
2340 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2342 Note that, at any time, the installer allows you to exit the current
2343 installation step and resume at a previous step, as show in the image below.
2345 @image{images/installer-resume,5in,, resuming the installation process}
2347 Once you're done, the installer produces an operating system configuration and
2348 displays it (@pxref{Using the Configuration System}). At that point you can
2349 hit ``OK'' and installation will proceed. On success, you can reboot into the
2350 new system and enjoy. @xref{After System Installation}, for what's next!
2353 @node Manual Installation
2354 @section Manual Installation
2356 This section describes how you would ``manually'' install GNU@tie{}Guix System
2357 on your machine. This option requires familiarity with GNU/Linux, with the
2358 shell, and with common administration tools. If you think this is not for
2359 you, consider using the guided graphical installer (@pxref{Guided Graphical
2362 The installation system provides root shells on TTYs 3 to 6; press
2363 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2364 many common tools needed to install the system, but is also a full-blown
2365 Guix System. This means that you can install additional packages, should you
2366 need it, using @command{guix package} (@pxref{Invoking guix package}).
2369 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2370 * Proceeding with the Installation:: Installing.
2373 @node Keyboard Layout and Networking and Partitioning
2374 @subsection Keyboard Layout, Networking, and Partitioning
2376 Before you can install the system, you may want to adjust the keyboard layout,
2377 set up networking, and partition your target hard disk. This section will
2378 guide you through this.
2380 @subsubsection Keyboard Layout
2382 @cindex keyboard layout
2383 The installation image uses the US qwerty keyboard layout. If you want
2384 to change it, you can use the @command{loadkeys} command. For example,
2385 the following command selects the Dvorak keyboard layout:
2391 See the files under @file{/run/current-system/profile/share/keymaps} for
2392 a list of available keyboard layouts. Run @command{man loadkeys} for
2395 @anchor{manual-installation-networking}
2396 @subsubsection Networking
2398 Run the following command to see what your network interfaces are called:
2405 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2411 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2412 Wired interfaces have a name starting with @samp{e}; for example, the
2413 interface corresponding to the first on-board Ethernet controller is
2414 called @samp{eno1}. Wireless interfaces have a name starting with
2415 @samp{w}, like @samp{w1p2s0}.
2418 @item Wired connection
2419 To configure a wired network run the following command, substituting
2420 @var{interface} with the name of the wired interface you want to use.
2423 ifconfig @var{interface} up
2427 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2430 ip link set @var{interface} up
2433 @item Wireless connection
2436 To configure wireless networking, you can create a configuration file
2437 for the @command{wpa_supplicant} configuration tool (its location is not
2438 important) using one of the available text editors such as
2442 nano wpa_supplicant.conf
2445 As an example, the following stanza can go to this file and will work
2446 for many wireless networks, provided you give the actual SSID and
2447 passphrase for the network you are connecting to:
2451 ssid="@var{my-ssid}"
2453 psk="the network's secret passphrase"
2457 Start the wireless service and run it in the background with the
2458 following command (substitute @var{interface} with the name of the
2459 network interface you want to use):
2462 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2465 Run @command{man wpa_supplicant} for more information.
2469 At this point, you need to acquire an IP address. On a network where IP
2470 addresses are automatically assigned @i{via} DHCP, you can run:
2473 dhclient -v @var{interface}
2476 Try to ping a server to see if networking is up and running:
2482 Setting up network access is almost always a requirement because the
2483 image does not contain all the software and tools that may be needed.
2485 @cindex proxy, during system installation
2486 If you need HTTP and HTTPS access to go through a proxy, run the
2490 herd set-http-proxy guix-daemon @var{URL}
2494 where @var{URL} is the proxy URL, for example
2495 @code{http://example.org:8118}.
2497 @cindex installing over SSH
2498 If you want to, you can continue the installation remotely by starting
2502 herd start ssh-daemon
2505 Make sure to either set a password with @command{passwd}, or configure
2506 OpenSSH public key authentication before logging in.
2508 @subsubsection Disk Partitioning
2510 Unless this has already been done, the next step is to partition, and
2511 then format the target partition(s).
2513 The installation image includes several partitioning tools, including
2514 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2515 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2516 the partition layout you want:
2522 If your disk uses the GUID Partition Table (GPT) format and you plan to
2523 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2524 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2527 @cindex EFI, installation
2528 @cindex UEFI, installation
2529 @cindex ESP, EFI system partition
2530 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2531 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2532 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2535 parted /dev/sda set 1 esp on
2539 @vindex grub-bootloader
2540 @vindex grub-efi-bootloader
2541 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2542 @file{/sys/firmware/efi} exists in the installation image, then you should
2543 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2544 Otherwise you should use the BIOS-based GRUB, known as
2545 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2549 Once you are done partitioning the target hard disk drive, you have to
2550 create a file system on the relevant partition(s)@footnote{Currently
2551 Guix System only supports ext4, btrfs, JFS, F2FS, and XFS file systems. In
2552 particular, code that reads file system UUIDs and labels only works for these
2553 file system types.}. For the ESP, if you have one and assuming it is
2554 @file{/dev/sda1}, run:
2557 mkfs.fat -F32 /dev/sda1
2560 For the root file system, ext4 is the most widely used format. Other
2561 file systems, such as Btrfs, support compression, which is reported to
2562 nicely complement file deduplication that the daemon performs
2563 independently of the file system (@pxref{Invoking guix-daemon,
2566 Preferably, assign file systems a label so that you can easily and
2567 reliably refer to them in @code{file-system} declarations (@pxref{File
2568 Systems}). This is typically done using the @code{-L} option of
2569 @command{mkfs.ext4} and related commands. So, assuming the target root
2570 partition lives at @file{/dev/sda2}, a file system with the label
2571 @code{my-root} can be created with:
2574 mkfs.ext4 -L my-root /dev/sda2
2577 @cindex encrypted disk
2578 If you are instead planning to encrypt the root partition, you can use
2579 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2580 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2581 @code{man cryptsetup}} for more information).
2584 Note that GRUB can unlock LUKS2 devices since version 2.06, but only
2585 supports the PBKDF2 key derivation function, which is not the default
2586 for @command{cryptsetup luksFormat}. You can check which key derivation
2587 function is being used by a device by running @command{cryptsetup
2588 luksDump @var{device}}, and looking for the PBKDF field of your
2592 Assuming you want to store the root partition on @file{/dev/sda2}, the
2593 command sequence to format it as a LUKS2 partition would be along these
2597 cryptsetup luksFormat --type luks2 --pbkdf pbkdf2 /dev/sda2
2598 cryptsetup open /dev/sda2 my-partition
2599 mkfs.ext4 -L my-root /dev/mapper/my-partition
2602 Once that is done, mount the target file system under @file{/mnt}
2603 with a command like (again, assuming @code{my-root} is the label of the
2607 mount LABEL=my-root /mnt
2610 Also mount any other file systems you would like to use on the target
2611 system relative to this path. If you have opted for @file{/boot/efi} as an
2612 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2613 found by @code{guix system init} afterwards.
2615 Finally, if you plan to use one or more swap partitions (@pxref{Swap
2616 Space}), make sure to initialize them with @command{mkswap}. Assuming
2617 you have one swap partition on @file{/dev/sda3}, you would run:
2624 Alternatively, you may use a swap file. For example, assuming that in
2625 the new system you want to use the file @file{/swapfile} as a swap file,
2626 you would run@footnote{This example will work for many types of file
2627 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2628 btrfs), the required steps may be different. For details, see the
2629 manual pages for @command{mkswap} and @command{swapon}.}:
2632 # This is 10 GiB of swap space. Adjust "count" to change the size.
2633 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2634 # For security, make the file readable and writable only by root.
2635 chmod 600 /mnt/swapfile
2636 mkswap /mnt/swapfile
2637 swapon /mnt/swapfile
2640 Note that if you have encrypted the root partition and created a swap
2641 file in its file system as described above, then the encryption also
2642 protects the swap file, just like any other file in that file system.
2644 @node Proceeding with the Installation
2645 @subsection Proceeding with the Installation
2647 With the target partitions ready and the target root mounted on
2648 @file{/mnt}, we're ready to go. First, run:
2651 herd start cow-store /mnt
2654 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2655 during the installation phase are written to the target disk on @file{/mnt}
2656 rather than kept in memory. This is necessary because the first phase of
2657 the @command{guix system init} command (see below) entails downloads or
2658 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2660 Next, you have to edit a file and
2661 provide the declaration of the operating system to be installed. To
2662 that end, the installation system comes with three text editors. We
2663 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2664 supports syntax highlighting and parentheses matching; other editors
2665 include mg (an Emacs clone), and
2666 nvi (a clone of the original BSD @command{vi} editor).
2667 We strongly recommend storing that file on the target root file system, say,
2668 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2669 configuration file once you have rebooted into the newly-installed system.
2671 @xref{Using the Configuration System}, for an overview of the
2672 configuration file. The example configurations discussed in that
2673 section are available under @file{/etc/configuration} in the
2674 installation image. Thus, to get started with a system configuration
2675 providing a graphical display server (a ``desktop'' system), you can run
2676 something along these lines:
2680 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2681 # nano /mnt/etc/config.scm
2684 You should pay attention to what your configuration file contains, and
2689 Make sure the @code{bootloader-configuration} form refers to the targets
2690 you want to install GRUB on. It should mention @code{grub-bootloader}
2691 if you are installing GRUB in the legacy way, or
2692 @code{grub-efi-bootloader} for newer UEFI systems. For legacy systems,
2693 the @code{targets} field contain the names of the devices, like
2694 @code{(list "/dev/sda")}; for UEFI systems it names the paths to mounted
2695 EFI partitions, like @code{(list "/boot/efi")}; do make sure the paths
2696 are currently mounted and a @code{file-system} entry is specified in
2700 Be sure that your file system labels match the value of their respective
2701 @code{device} fields in your @code{file-system} configuration, assuming
2702 your @code{file-system} configuration uses the @code{file-system-label}
2703 procedure in its @code{device} field.
2706 If there are encrypted or RAID partitions, make sure to add a
2707 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2710 Once you are done preparing the configuration file, the new system must
2711 be initialized (remember that the target root file system is mounted
2715 guix system init /mnt/etc/config.scm /mnt
2719 This copies all the necessary files and installs GRUB on
2720 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2721 more information, @pxref{Invoking guix system}. This command may trigger
2722 downloads or builds of missing packages, which can take some time.
2724 Once that command has completed---and hopefully succeeded!---you can run
2725 @command{reboot} and boot into the new system. The @code{root} password
2726 in the new system is initially empty; other users' passwords need to be
2727 initialized by running the @command{passwd} command as @code{root},
2728 unless your configuration specifies otherwise
2729 (@pxref{user-account-password, user account passwords}).
2730 @xref{After System Installation}, for what's next!
2733 @node After System Installation
2734 @section After System Installation
2736 Success, you've now booted into Guix System! From then on, you can update the
2737 system whenever you want by running, say:
2741 sudo guix system reconfigure /etc/config.scm
2745 This builds a new system generation with the latest packages and services
2746 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2747 your system includes the latest security updates (@pxref{Security Updates}).
2749 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2751 @cindex sudo vs. @command{guix pull}
2752 Note that @command{sudo guix} runs your user's @command{guix} command and
2753 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2754 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2756 The difference matters here, because @command{guix pull} updates
2757 the @command{guix} command and package definitions only for the user it is run
2758 as. This means that if you choose to use @command{guix system reconfigure} in
2759 root's login shell, you'll need to @command{guix pull} separately.
2762 Now, @pxref{Getting Started}, and
2763 join us on @code{#guix} on the Libera Chat IRC network or on
2764 @email{guix-devel@@gnu.org} to share your experience!
2767 @node Installing Guix in a VM
2768 @section Installing Guix in a Virtual Machine
2770 @cindex virtual machine, Guix System installation
2771 @cindex virtual private server (VPS)
2772 @cindex VPS (virtual private server)
2773 If you'd like to install Guix System in a virtual machine (VM) or on a
2774 virtual private server (VPS) rather than on your beloved machine, this
2777 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2778 disk image, follow these steps:
2782 First, retrieve and decompress the Guix system installation image as
2783 described previously (@pxref{USB Stick and DVD Installation}).
2786 Create a disk image that will hold the installed system. To make a
2787 qcow2-formatted disk image, use the @command{qemu-img} command:
2790 qemu-img create -f qcow2 guix-system.img 50G
2793 The resulting file will be much smaller than 50 GB (typically less than
2794 1 MB), but it will grow as the virtualized storage device is filled up.
2797 Boot the USB installation image in an VM:
2800 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2801 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2802 -drive file=guix-system.img \
2803 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2806 @code{-enable-kvm} is optional, but significantly improves performance,
2807 @pxref{Running Guix in a VM}.
2810 You're now root in the VM, proceed with the installation process.
2811 @xref{Preparing for Installation}, and follow the instructions.
2814 Once installation is complete, you can boot the system that's on your
2815 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2818 @node Building the Installation Image
2819 @section Building the Installation Image
2821 @cindex installation image
2822 The installation image described above was built using the @command{guix
2823 system} command, specifically:
2826 guix system image -t iso9660 gnu/system/install.scm
2829 Have a look at @file{gnu/system/install.scm} in the source tree,
2830 and see also @ref{Invoking guix system} for more information
2831 about the installation image.
2833 @section Building the Installation Image for ARM Boards
2835 Many ARM boards require a specific variant of the
2836 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2838 If you build a disk image and the bootloader is not available otherwise
2839 (on another boot drive etc), it's advisable to build an image that
2840 includes the bootloader, specifically:
2843 guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2846 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2847 board, a list of possible boards will be printed.
2849 @c *********************************************************************
2850 @cindex troubleshooting, guix system
2851 @cindex guix system troubleshooting
2852 @node System Troubleshooting Tips
2853 @chapter System Troubleshooting Tips
2855 Guix System allows rebooting into a previous generation should the last
2856 one be malfunctioning, which makes it quite robust against being broken
2857 irreversibly. This feature depends on GRUB being correctly functioning
2858 though, which means that if for whatever reasons your GRUB installation
2859 becomes corrupted during a system reconfiguration, you may not be able
2860 to easily boot into a previous generation. A technique that can be used
2861 in this case is to @i{chroot} into your broken system and reconfigure it
2862 from there. Such technique is explained below.
2864 @cindex chroot, guix system
2865 @cindex chrooting, guix system
2866 @cindex repairing GRUB, via chroot
2867 @node Chrooting into an existing system
2868 @section Chrooting into an existing system
2870 This section details how to @i{chroot} to an already installed Guix
2871 System with the aim of reconfiguring it, for example to fix a broken
2872 GRUB installation. The process is similar to how it would be done on
2873 other GNU/Linux systems, but there are some Guix System particularities
2874 such as the daemon and profiles that make it worthy of explaining here.
2878 Obtain a bootable image of Guix System. It is recommended the latest
2879 development snapshot so the kernel and the tools used are at least as as
2880 new as those of your installed system; it can be retrieved from the
2881 @url{https://ci.guix.gnu.org/search/latest/ISO-9660?query=spec:images+status:success+system:x86_64-linux+image.iso,
2882 https://ci.guix.gnu.org} URL. Follow the @pxref{USB Stick and DVD
2883 Installation} section for copying it to a bootable media.
2886 Boot the image, and proceed with the graphical text-based installer
2887 until your network is configured. Alternatively, you could configure
2888 the network manually by following the
2889 @ref{manual-installation-networking} section. If you get the error
2890 @samp{RTNETLINK answers: Operation not possible due to RF-kill}, try
2891 @samp{rfkill list} followed by @samp{rfkill unblock 0}, where @samp{0}
2892 is your device identifier (ID).
2895 Switch to a virtual console (tty) if you haven't already by pressing
2896 simultaneously the @kbd{Control + Alt + F4} keys. Mount your file
2897 system at @file{/mnt}. Assuming your root partition is
2898 @file{/dev/sda2}, you would do:
2901 mount /dev/sda2 /mnt
2905 Mount special block devices and Linux-specific directories:
2908 mount --bind /proc /mnt/proc
2909 mount --bind /sys /mnt/sys
2910 mount --bind /dev /mnt/dev
2913 If your system is EFI-based, you must also mount the ESP partition.
2914 Assuming it is @file{/dev/sda1}, you can do so with:
2917 mount /dev/sda1 /mnt/boot/efi
2921 Enter your system via chroot:
2928 Source your @var{user} profile to setup the environment, where
2929 @var{user} is the user name used for the Guix System you are attempting
2933 source /home/@var{user}/.guix-profile/etc/profile
2936 To ensure you are working with the Guix revision you normally would as
2937 your normal user, also source your current Guix profile:
2940 source /home/@var{user}/.config/guix/current/etc/profile
2944 Start a minimal @command{guix-daemon} in the background:
2947 guix-daemon --build-users-group=guixbuild --disable-chroot &
2951 Edit your Guix System configuration if needed, then reconfigure with:
2954 guix system reconfigure your-config.scm
2958 Finally, you should be good to reboot the system to test your fix.
2962 @c *********************************************************************
2963 @node Getting Started
2964 @chapter Getting Started
2966 Presumably, you've reached this section because either you have
2967 installed Guix on top of another distribution (@pxref{Installation}), or
2968 you've installed the standalone Guix System (@pxref{System
2969 Installation}). It's time for you to get started using Guix and this
2970 section aims to help you do that and give you a feel of what it's like.
2972 Guix is about installing software, so probably the first thing you'll
2973 want to do is to actually look for software. Let's say you're looking
2974 for a text editor, you can run:
2977 guix search text editor
2980 This command shows you a number of matching @dfn{packages}, each time
2981 showing the package's name, version, a description, and additional info.
2982 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2983 you can go ahead and install it (run this command as a regular user,
2984 @emph{no need for root privileges}!):
2991 You've installed your first package, congrats! The package is now
2992 visible in your default @dfn{profile}, @file{$HOME/.guix-profile}---a
2993 profile is a directory containing installed packages.
2994 In the process, you've
2995 probably noticed that Guix downloaded pre-built binaries; or, if you
2996 explicitly chose to @emph{not} use pre-built binaries, then probably
2997 Guix is still building software (@pxref{Substitutes}, for more info).
2999 Unless you're using Guix System, the @command{guix install} command must
3000 have printed this hint:
3003 hint: Consider setting the necessary environment variables by running:
3005 GUIX_PROFILE="$HOME/.guix-profile"
3006 . "$GUIX_PROFILE/etc/profile"
3008 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
3011 Indeed, you must now tell your shell where @command{emacs} and other
3012 programs installed with Guix are to be found. Pasting the two lines
3013 above will do just that: it will add
3014 @code{$HOME/.guix-profile/bin}---which is where the installed package
3015 is---to the @code{PATH} environment variable. You can paste these two
3016 lines in your shell so they take effect right away, but more importantly
3017 you should add them to @file{~/.bash_profile} (or equivalent file if you
3018 do not use Bash) so that environment variables are set next time you
3019 spawn a shell. You only need to do this once and other search paths
3020 environment variables will be taken care of similarly---e.g., if you
3021 eventually install @code{python} and Python libraries,
3022 @env{GUIX_PYTHONPATH} will be defined.
3024 You can go on installing packages at your will. To list installed
3028 guix package --list-installed
3031 To remove a package, you would unsurprisingly run @command{guix remove}.
3032 A distinguishing feature is the ability to @dfn{roll back} any operation
3033 you made---installation, removal, upgrade---by simply typing:
3036 guix package --roll-back
3039 This is because each operation is in fact a @dfn{transaction} that
3040 creates a new @dfn{generation}. These generations and the difference
3041 between them can be displayed by running:
3044 guix package --list-generations
3047 Now you know the basics of package management!
3049 @quotation Going further
3050 @xref{Package Management}, for more about package management. You may
3051 like @dfn{declarative} package management with @command{guix package
3052 --manifest}, managing separate @dfn{profiles} with @option{--profile},
3053 deleting old generations, collecting garbage, and other nifty features
3054 that will come in handy as you become more familiar with Guix. If you
3055 are a developer, @pxref{Development} for additional tools. And if
3056 you're curious, @pxref{Features}, to peek under the hood.
3059 Once you've installed a set of packages, you will want to periodically
3060 @emph{upgrade} them to the latest and greatest version. To do that, you
3061 will first pull the latest revision of Guix and its package collection:
3067 The end result is a new @command{guix} command, under
3068 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
3069 first time you run @command{guix pull}, be sure to follow the hint that
3070 the command prints and, similar to what we saw above, paste these two
3071 lines in your terminal and @file{.bash_profile}:
3074 GUIX_PROFILE="$HOME/.config/guix/current"
3075 . "$GUIX_PROFILE/etc/profile"
3079 You must also instruct your shell to point to this new @command{guix}:
3085 At this point, you're running a brand new Guix. You can thus go ahead
3086 and actually upgrade all the packages you previously installed:
3092 As you run this command, you will see that binaries are downloaded (or
3093 perhaps some packages are built), and eventually you end up with the
3094 upgraded packages. Should one of these upgraded packages not be to your
3095 liking, remember you can always roll back!
3097 You can display the exact revision of Guix you're currently using by
3104 The information it displays is @emph{all it takes to reproduce the exact
3105 same Guix}, be it at a different point in time or on a different
3108 @quotation Going further
3109 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
3110 how to specify additional @dfn{channels} to pull packages from, how to
3111 replicate Guix, and more. You may also find @command{time-machine}
3112 handy (@pxref{Invoking guix time-machine}).
3115 If you installed Guix System, one of the first things you'll want to do
3116 is to upgrade your system. Once you've run @command{guix pull} to get
3117 the latest Guix, you can upgrade the system like this:
3120 sudo guix system reconfigure /etc/config.scm
3123 Upon completion, the system runs the latest versions of its software
3124 packages. When you eventually reboot, you'll notice a sub-menu in the
3125 bootloader that reads ``Old system generations'': it's what allows you
3126 to boot @emph{an older generation of your system}, should the latest
3127 generation be ``broken'' or otherwise unsatisfying. Just like for
3128 packages, you can always @emph{roll back} to a previous generation
3129 @emph{of the whole system}:
3132 sudo guix system roll-back
3135 There are many things you'll probably want to tweak on your system:
3136 adding new user accounts, adding new system services, fiddling with the
3137 configuration of those services, etc. The system configuration is
3138 @emph{entirely} described in the @file{/etc/config.scm} file.
3139 @xref{Using the Configuration System}, to learn how to change it.
3141 Now you know enough to get started!
3143 @quotation Resources
3144 The rest of this manual provides a reference for all things Guix. Here
3145 are some additional resources you may find useful:
3149 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
3150 ``how-to'' style of recipes for a variety of applications.
3153 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
3154 Card} lists in two pages most of the commands and options you'll ever
3158 The web site contains @uref{https://guix.gnu.org/en/videos/,
3159 instructional videos} covering topics such as everyday use of Guix, how
3160 to get help, and how to become a contributor.
3163 @xref{Documentation}, to learn how to access documentation on your
3167 We hope you will enjoy Guix as much as the community enjoys building it!
3170 @c *********************************************************************
3171 @node Package Management
3172 @chapter Package Management
3175 The purpose of GNU Guix is to allow users to easily install, upgrade, and
3176 remove software packages, without having to know about their build
3177 procedures or dependencies. Guix also goes beyond this obvious set of
3180 This chapter describes the main features of Guix, as well as the
3181 package management tools it provides. Along with the command-line
3182 interface described below (@pxref{Invoking guix package, @code{guix
3183 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
3184 emacs-guix, The Emacs-Guix Reference Manual}), after installing
3185 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
3189 guix install emacs-guix
3193 * Features:: How Guix will make your life brighter.
3194 * Invoking guix package:: Package installation, removal, etc.
3195 * Substitutes:: Downloading pre-built binaries.
3196 * Packages with Multiple Outputs:: Single source package, multiple outputs.
3197 * Invoking guix gc:: Running the garbage collector.
3198 * Invoking guix pull:: Fetching the latest Guix and distribution.
3199 * Invoking guix time-machine:: Running an older revision of Guix.
3200 * Inferiors:: Interacting with another revision of Guix.
3201 * Invoking guix describe:: Display information about your Guix revision.
3202 * Invoking guix archive:: Exporting and importing store files.
3208 Here we assume you've already made your first steps with Guix
3209 (@pxref{Getting Started}) and would like to get an overview about what's
3210 going on under the hood.
3212 When using Guix, each package ends up in the @dfn{package store}, in its
3213 own directory---something that resembles
3214 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
3216 Instead of referring to these directories, users have their own
3217 @dfn{profile}, which points to the packages that they actually want to
3218 use. These profiles are stored within each user's home directory, at
3219 @code{$HOME/.guix-profile}.
3221 For example, @code{alice} installs GCC 4.7.2. As a result,
3222 @file{/home/alice/.guix-profile/bin/gcc} points to
3223 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
3224 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
3225 simply continues to point to
3226 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
3227 coexist on the same system without any interference.
3229 The @command{guix package} command is the central tool to manage
3230 packages (@pxref{Invoking guix package}). It operates on the per-user
3231 profiles, and can be used @emph{with normal user privileges}.
3233 @cindex transactions
3234 The command provides the obvious install, remove, and upgrade
3235 operations. Each invocation is actually a @emph{transaction}: either
3236 the specified operation succeeds, or nothing happens. Thus, if the
3237 @command{guix package} process is terminated during the transaction,
3238 or if a power outage occurs during the transaction, then the user's
3239 profile remains in its previous state, and remains usable.
3241 In addition, any package transaction may be @emph{rolled back}. So, if,
3242 for example, an upgrade installs a new version of a package that turns
3243 out to have a serious bug, users may roll back to the previous instance
3244 of their profile, which was known to work well. Similarly, the global
3245 system configuration on Guix is subject to
3246 transactional upgrades and roll-back
3247 (@pxref{Using the Configuration System}).
3249 All packages in the package store may be @emph{garbage-collected}.
3250 Guix can determine which packages are still referenced by user
3251 profiles, and remove those that are provably no longer referenced
3252 (@pxref{Invoking guix gc}). Users may also explicitly remove old
3253 generations of their profile so that the packages they refer to can be
3256 @cindex reproducibility
3257 @cindex reproducible builds
3258 Guix takes a @dfn{purely functional} approach to package
3259 management, as described in the introduction (@pxref{Introduction}).
3260 Each @file{/gnu/store} package directory name contains a hash of all the
3261 inputs that were used to build that package---compiler, libraries, build
3262 scripts, etc. This direct correspondence allows users to make sure a
3263 given package installation matches the current state of their
3264 distribution. It also helps maximize @dfn{build reproducibility}:
3265 thanks to the isolated build environments that are used, a given build
3266 is likely to yield bit-identical files when performed on different
3267 machines (@pxref{Invoking guix-daemon, container}).
3270 This foundation allows Guix to support @dfn{transparent binary/source
3271 deployment}. When a pre-built binary for a @file{/gnu/store} item is
3272 available from an external source---a @dfn{substitute}, Guix just
3273 downloads it and unpacks it;
3274 otherwise, it builds the package from source, locally
3275 (@pxref{Substitutes}). Because build results are usually bit-for-bit
3276 reproducible, users do not have to trust servers that provide
3277 substitutes: they can force a local build and @emph{challenge} providers
3278 (@pxref{Invoking guix challenge}).
3280 Control over the build environment is a feature that is also useful for
3281 developers. The @command{guix shell} command allows developers of
3282 a package to quickly set up the right development environment for their
3283 package, without having to manually install the dependencies of the
3284 package into their profile (@pxref{Invoking guix shell}).
3286 @cindex replication, of software environments
3287 @cindex provenance tracking, of software artifacts
3288 All of Guix and its package definitions is version-controlled, and
3289 @command{guix pull} allows you to ``travel in time'' on the history of Guix
3290 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
3291 Guix instance on a different machine or at a later point in time, which in
3292 turn allows you to @emph{replicate complete software environments}, while
3293 retaining precise @dfn{provenance tracking} of the software.
3295 @node Invoking guix package
3296 @section Invoking @command{guix package}
3298 @cindex installing packages
3299 @cindex removing packages
3300 @cindex package installation
3301 @cindex package removal
3303 The @command{guix package} command is the tool that allows users to
3304 install, upgrade, and remove packages, as well as rolling back to
3305 previous configurations. These operations work on a user
3306 @dfn{profile}---a directory of installed packages. Each user has a
3307 default profile in @file{$HOME/.guix-profile}.
3308 The command operates only on the user's own profile,
3309 and works with normal user privileges (@pxref{Features}). Its syntax
3313 guix package @var{options}
3316 @cindex transactions
3317 Primarily, @var{options} specifies the operations to be performed during
3318 the transaction. Upon completion, a new profile is created, but
3319 previous @dfn{generations} of the profile remain available, should the user
3322 For example, to remove @code{lua} and install @code{guile} and
3323 @code{guile-cairo} in a single transaction:
3326 guix package -r lua -i guile guile-cairo
3329 @cindex aliases, for @command{guix package}
3330 For your convenience, we also provide the following aliases:
3334 @command{guix search} is an alias for @command{guix package -s},
3336 @command{guix install} is an alias for @command{guix package -i},
3338 @command{guix remove} is an alias for @command{guix package -r},
3340 @command{guix upgrade} is an alias for @command{guix package -u},
3342 and @command{guix show} is an alias for @command{guix package --show=}.
3345 These aliases are less expressive than @command{guix package} and provide
3346 fewer options, so in some cases you'll probably want to use @command{guix
3349 @command{guix package} also supports a @dfn{declarative approach}
3350 whereby the user specifies the exact set of packages to be available and
3351 passes it @i{via} the @option{--manifest} option
3352 (@pxref{profile-manifest, @option{--manifest}}).
3355 For each user, a symlink to the user's default profile is automatically
3356 created in @file{$HOME/.guix-profile}. This symlink always points to the
3357 current generation of the user's default profile. Thus, users can add
3358 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3359 variable, and so on.
3360 @cindex search paths
3361 If you are not using Guix System, consider adding the
3362 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3363 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3364 shells get all the right environment variable definitions:
3367 GUIX_PROFILE="$HOME/.guix-profile" ; \
3368 source "$GUIX_PROFILE/etc/profile"
3371 In a multi-user setup, user profiles are stored in a place registered as
3372 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3373 to (@pxref{Invoking guix gc}). That directory is normally
3374 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3375 @var{localstatedir} is the value passed to @code{configure} as
3376 @option{--localstatedir}, and @var{user} is the user name. The
3377 @file{per-user} directory is created when @command{guix-daemon} is
3378 started, and the @var{user} sub-directory is created by @command{guix
3381 The @var{options} can be among the following:
3385 @item --install=@var{package} @dots{}
3386 @itemx -i @var{package} @dots{}
3387 Install the specified @var{package}s.
3389 Each @var{package} may specify either a simple package name, such as
3390 @code{guile}, or a package name followed by an at-sign and version number,
3391 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3392 case, the newest version prefixed by @code{1.8} is selected).
3394 If no version number is specified, the
3395 newest available version will be selected. In addition, @var{package}
3396 may contain a colon, followed by the name of one of the outputs of the
3397 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3398 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3399 name (and optionally version) are searched for among the GNU
3400 distribution modules (@pxref{Package Modules}).
3402 @cindex propagated inputs
3403 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3404 that automatically get installed along with the required package
3405 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3406 @code{package} objects}, for information about propagated inputs in
3407 package definitions).
3409 @anchor{package-cmd-propagated-inputs}
3410 An example is the GNU MPC library: its C header files refer to those of
3411 the GNU MPFR library, which in turn refer to those of the GMP library.
3412 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3413 in the profile; removing MPC also removes MPFR and GMP---unless they had
3414 also been explicitly installed by the user.
3416 Besides, packages sometimes rely on the definition of environment
3417 variables for their search paths (see explanation of
3418 @option{--search-paths} below). Any missing or possibly incorrect
3419 environment variable definitions are reported here.
3421 @item --install-from-expression=@var{exp}
3423 Install the package @var{exp} evaluates to.
3425 @var{exp} must be a Scheme expression that evaluates to a
3426 @code{<package>} object. This option is notably useful to disambiguate
3427 between same-named variants of a package, with expressions such as
3428 @code{(@@ (gnu packages base) guile-final)}.
3430 Note that this option installs the first output of the specified
3431 package, which may be insufficient when needing a specific output of a
3432 multiple-output package.
3434 @item --install-from-file=@var{file}
3435 @itemx -f @var{file}
3436 Install the package that the code within @var{file} evaluates to.
3438 As an example, @var{file} might contain a definition like this
3439 (@pxref{Defining Packages}):
3442 @include package-hello.scm
3445 Developers may find it useful to include such a @file{guix.scm} file
3446 in the root of their project source tree that can be used to test
3447 development snapshots and create reproducible development environments
3448 (@pxref{Invoking guix shell}).
3450 The @var{file} may also contain a JSON representation of one or more
3451 package definitions. Running @code{guix package -f} on
3452 @file{hello.json} with the following contents would result in installing
3453 the package @code{greeter} after building @code{myhello}:
3456 @verbatiminclude package-hello.json
3459 @item --remove=@var{package} @dots{}
3460 @itemx -r @var{package} @dots{}
3461 Remove the specified @var{package}s.
3463 As for @option{--install}, each @var{package} may specify a version number
3464 and/or output name in addition to the package name. For instance,
3465 @samp{-r glibc:debug} would remove the @code{debug} output of
3468 @item --upgrade[=@var{regexp} @dots{}]
3469 @itemx -u [@var{regexp} @dots{}]
3470 @cindex upgrading packages
3471 Upgrade all the installed packages. If one or more @var{regexp}s are
3472 specified, upgrade only installed packages whose name matches a
3473 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3475 Note that this upgrades package to the latest version of packages found
3476 in the distribution currently installed. To update your distribution,
3477 you should regularly run @command{guix pull} (@pxref{Invoking guix
3480 @cindex package transformations, upgrades
3481 When upgrading, package transformations that were originally applied
3482 when creating the profile are automatically re-applied (@pxref{Package
3483 Transformation Options}). For example, assume you first installed Emacs
3484 from the tip of its development branch with:
3487 guix install emacs-next --with-branch=emacs-next=master
3490 Next time you run @command{guix upgrade}, Guix will again pull the tip
3491 of the Emacs development branch and build @code{emacs-next} from that
3494 Note that transformation options such as @option{--with-branch} and
3495 @option{--with-source} depend on external state; it is up to you to
3496 ensure that they work as expected. You can also discard a
3497 transformations that apply to a package by running:
3500 guix install @var{package}
3503 @item --do-not-upgrade[=@var{regexp} @dots{}]
3504 When used together with the @option{--upgrade} option, do @emph{not}
3505 upgrade any packages whose name matches a @var{regexp}. For example, to
3506 upgrade all packages in the current profile except those containing the
3507 substring ``emacs'':
3510 $ guix package --upgrade . --do-not-upgrade emacs
3513 @item @anchor{profile-manifest}--manifest=@var{file}
3514 @itemx -m @var{file}
3515 @cindex profile declaration
3516 @cindex profile manifest
3517 Create a new generation of the profile from the manifest object
3518 returned by the Scheme code in @var{file}. This option can be repeated
3519 several times, in which case the manifests are concatenated.
3521 This allows you to @emph{declare} the profile's contents rather than
3522 constructing it through a sequence of @option{--install} and similar
3523 commands. The advantage is that @var{file} can be put under version
3524 control, copied to different machines to reproduce the same profile, and
3527 @var{file} must return a @dfn{manifest} object, which is roughly a list
3530 @findex packages->manifest
3532 (use-package-modules guile emacs)
3537 ;; Use a specific package output.
3538 (list guile-2.0 "debug")))
3541 @xref{Writing Manifests}, for information on how to write a manifest.
3542 @xref{export-manifest, @option{--export-manifest}}, to learn how to
3543 obtain a manifest file from an existing profile.
3546 @cindex rolling back
3547 @cindex undoing transactions
3548 @cindex transactions, undoing
3549 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3550 the last transaction.
3552 When combined with options such as @option{--install}, roll back occurs
3553 before any other actions.
3555 When rolling back from the first generation that actually contains
3556 installed packages, the profile is made to point to the @dfn{zeroth
3557 generation}, which contains no files apart from its own metadata.
3559 After having rolled back, installing, removing, or upgrading packages
3560 overwrites previous future generations. Thus, the history of the
3561 generations in a profile is always linear.
3563 @item --switch-generation=@var{pattern}
3564 @itemx -S @var{pattern}
3566 Switch to a particular generation defined by @var{pattern}.
3568 @var{pattern} may be either a generation number or a number prefixed
3569 with ``+'' or ``-''. The latter means: move forward/backward by a
3570 specified number of generations. For example, if you want to return to
3571 the latest generation after @option{--roll-back}, use
3572 @option{--switch-generation=+1}.
3574 The difference between @option{--roll-back} and
3575 @option{--switch-generation=-1} is that @option{--switch-generation} will
3576 not make a zeroth generation, so if a specified generation does not
3577 exist, the current generation will not be changed.
3579 @item --search-paths[=@var{kind}]
3580 @cindex search paths
3581 Report environment variable definitions, in Bash syntax, that may be
3582 needed in order to use the set of installed packages. These environment
3583 variables are used to specify @dfn{search paths} for files used by some
3584 of the installed packages.
3586 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3587 environment variables to be defined so it can look for headers and
3588 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3589 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3590 library are installed in the profile, then @option{--search-paths} will
3591 suggest setting these variables to @file{@var{profile}/include} and
3592 @file{@var{profile}/lib}, respectively (@pxref{Search Paths}, for info
3593 on search path specifications associated with packages.)
3595 The typical use case is to define these environment variables in the
3599 $ eval $(guix package --search-paths)
3602 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3603 meaning that the returned environment variable definitions will either
3604 be exact settings, or prefixes or suffixes of the current value of these
3605 variables. When omitted, @var{kind} defaults to @code{exact}.
3607 This option can also be used to compute the @emph{combined} search paths
3608 of several profiles. Consider this example:
3611 $ guix package -p foo -i guile
3612 $ guix package -p bar -i guile-json
3613 $ guix package -p foo -p bar --search-paths
3616 The last command above reports about the @env{GUILE_LOAD_PATH}
3617 variable, even though, taken individually, neither @file{foo} nor
3618 @file{bar} would lead to that recommendation.
3621 @cindex profile, choosing
3622 @item --profile=@var{profile}
3623 @itemx -p @var{profile}
3624 Use @var{profile} instead of the user's default profile.
3626 @var{profile} must be the name of a file that will be created upon
3627 completion. Concretely, @var{profile} will be a mere symbolic link
3628 (``symlink'') pointing to the actual profile where packages are
3632 $ guix install hello -p ~/code/my-profile
3634 $ ~/code/my-profile/bin/hello
3638 All it takes to get rid of the profile is to remove this symlink and its
3639 siblings that point to specific generations:
3642 $ rm ~/code/my-profile ~/code/my-profile-*-link
3645 @item --list-profiles
3646 List all the user's profiles:
3649 $ guix package --list-profiles
3650 /home/charlie/.guix-profile
3651 /home/charlie/code/my-profile
3652 /home/charlie/code/devel-profile
3653 /home/charlie/tmp/test
3656 When running as root, list all the profiles of all the users.
3658 @cindex collisions, in a profile
3659 @cindex colliding packages in profiles
3660 @cindex profile collisions
3661 @item --allow-collisions
3662 Allow colliding packages in the new profile. Use at your own risk!
3664 By default, @command{guix package} reports as an error @dfn{collisions}
3665 in the profile. Collisions happen when two or more different versions
3666 or variants of a given package end up in the profile.
3669 Use the bootstrap Guile to build the profile. This option is only
3670 useful to distribution developers.
3674 In addition to these actions, @command{guix package} supports the
3675 following options to query the current state of a profile, or the
3676 availability of packages:
3680 @item --search=@var{regexp}
3681 @itemx -s @var{regexp}
3682 @anchor{guix-search}
3683 @cindex searching for packages
3684 List the available packages whose name, synopsis, or description matches
3685 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3686 Print all the metadata of matching packages in
3687 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3688 GNU recutils manual}).
3690 This allows specific fields to be extracted using the @command{recsel}
3691 command, for instance:
3694 $ guix package -s malloc | recsel -p name,version,relevance
3708 Similarly, to show the name of all the packages available under the
3709 terms of the GNU@tie{}LGPL version 3:
3712 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3719 It is also possible to refine search results using several @code{-s} flags to
3720 @command{guix package}, or several arguments to @command{guix search}. For
3721 example, the following command returns a list of board games (this time using
3722 the @command{guix search} alias):
3725 $ guix search '\<board\>' game | recsel -p name
3730 If we were to omit @code{-s game}, we would also get software packages
3731 that deal with printed circuit boards; removing the angle brackets
3732 around @code{board} would further add packages that have to do with
3735 And now for a more elaborate example. The following command searches
3736 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3737 libraries, and prints the name and synopsis of the matching packages:
3740 $ guix search crypto library | \
3741 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3745 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3746 information on @dfn{selection expressions} for @code{recsel -e}.
3748 @item --show=@var{package}
3749 Show details about @var{package}, taken from the list of available packages, in
3750 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3754 $ guix package --show=guile | recsel -p name,version
3766 You may also specify the full name of a package to only get details about a
3767 specific version of it (this time using the @command{guix show} alias):
3769 $ guix show guile@@3.0.5 | recsel -p name,version
3774 @item --list-installed[=@var{regexp}]
3775 @itemx -I [@var{regexp}]
3776 List the currently installed packages in the specified profile, with the
3777 most recently installed packages shown last. When @var{regexp} is
3778 specified, list only installed packages whose name matches @var{regexp}.
3780 For each installed package, print the following items, separated by
3781 tabs: the package name, its version string, the part of the package that
3782 is installed (for instance, @code{out} for the default output,
3783 @code{include} for its headers, etc.), and the path of this package in
3786 @item --list-available[=@var{regexp}]
3787 @itemx -A [@var{regexp}]
3788 List packages currently available in the distribution for this system
3789 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3790 available packages whose name matches @var{regexp}.
3792 For each package, print the following items separated by tabs: its name,
3793 its version string, the parts of the package (@pxref{Packages with
3794 Multiple Outputs}), and the source location of its definition.
3796 @item --list-generations[=@var{pattern}]
3797 @itemx -l [@var{pattern}]
3799 Return a list of generations along with their creation dates; for each
3800 generation, show the installed packages, with the most recently
3801 installed packages shown last. Note that the zeroth generation is never
3804 For each installed package, print the following items, separated by
3805 tabs: the name of a package, its version string, the part of the package
3806 that is installed (@pxref{Packages with Multiple Outputs}), and the
3807 location of this package in the store.
3809 When @var{pattern} is used, the command returns only matching
3810 generations. Valid patterns include:
3813 @item @emph{Integers and comma-separated integers}. Both patterns denote
3814 generation numbers. For instance, @option{--list-generations=1} returns
3817 And @option{--list-generations=1,8,2} outputs three generations in the
3818 specified order. Neither spaces nor trailing commas are allowed.
3820 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3821 specified generations and everything in between. Note that the start of
3822 a range must be smaller than its end.
3824 It is also possible to omit the endpoint. For example,
3825 @option{--list-generations=2..}, returns all generations starting from the
3828 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3829 or months by passing an integer along with the first letter of the
3830 duration. For example, @option{--list-generations=20d} lists generations
3831 that are up to 20 days old.
3834 @item --delete-generations[=@var{pattern}]
3835 @itemx -d [@var{pattern}]
3836 When @var{pattern} is omitted, delete all generations except the current
3839 This command accepts the same patterns as @option{--list-generations}.
3840 When @var{pattern} is specified, delete the matching generations. When
3841 @var{pattern} specifies a duration, generations @emph{older} than the
3842 specified duration match. For instance, @option{--delete-generations=1m}
3843 deletes generations that are more than one month old.
3845 If the current generation matches, it is @emph{not} deleted. Also, the
3846 zeroth generation is never deleted.
3848 Note that deleting generations prevents rolling back to them.
3849 Consequently, this command must be used with care.
3851 @cindex manifest, exporting
3852 @anchor{export-manifest}
3853 @item --export-manifest
3854 Write to standard output a manifest suitable for @option{--manifest}
3855 corresponding to the chosen profile(s).
3857 This option is meant to help you migrate from the ``imperative''
3858 operating mode---running @command{guix install}, @command{guix upgrade},
3859 etc.---to the declarative mode that @option{--manifest} offers.
3861 Be aware that the resulting manifest @emph{approximates} what your
3862 profile actually contains; for instance, depending on how your profile
3863 was created, it can refer to packages or package versions that are not
3864 exactly what you specified.
3866 Keep in mind that a manifest is purely symbolic: it only contains
3867 package names and possibly versions, and their meaning varies over time.
3868 If you wish to ``pin'' channels to the revisions that were used to build
3869 the profile(s), see @option{--export-channels} below.
3871 @cindex pinning, channel revisions of a profile
3872 @item --export-channels
3873 Write to standard output the list of channels used by the chosen
3874 profile(s), in a format suitable for @command{guix pull --channels} or
3875 @command{guix time-machine --channels} (@pxref{Channels}).
3877 Together with @option{--export-manifest}, this option provides
3878 information allowing you to replicate the current profile
3879 (@pxref{Replicating Guix}).
3881 However, note that the output of this command @emph{approximates} what
3882 was actually used to build this profile. In particular, a single
3883 profile might have been built from several different revisions of the
3884 same channel. In that case, @option{--export-manifest} chooses the last
3885 one and writes the list of other revisions in a comment. If you really
3886 need to pick packages from different channel revisions, you can use
3887 inferiors in your manifest to do so (@pxref{Inferiors}).
3889 Together with @option{--export-manifest}, this is a good starting point
3890 if you are willing to migrate from the ``imperative'' model to the fully
3891 declarative model consisting of a manifest file along with a channels
3892 file pinning the exact channel revision(s) you want.
3895 Finally, since @command{guix package} may actually start build
3896 processes, it supports all the common build options (@pxref{Common Build
3897 Options}). It also supports package transformation options, such as
3898 @option{--with-source}, and preserves them across upgrades
3899 (@pxref{Package Transformation Options}).
3902 @section Substitutes
3905 @cindex pre-built binaries
3906 Guix supports transparent source/binary deployment, which means that it
3907 can either build things locally, or download pre-built items from a
3908 server, or both. We call these pre-built items @dfn{substitutes}---they
3909 are substitutes for local build results. In many cases, downloading a
3910 substitute is much faster than building things locally.
3912 Substitutes can be anything resulting from a derivation build
3913 (@pxref{Derivations}). Of course, in the common case, they are
3914 pre-built package binaries, but source tarballs, for instance, which
3915 also result from derivation builds, can be available as substitutes.
3918 * Official Substitute Servers:: One particular source of substitutes.
3919 * Substitute Server Authorization:: How to enable or disable substitutes.
3920 * Getting Substitutes from Other Servers:: Substitute diversity.
3921 * Substitute Authentication:: How Guix verifies substitutes.
3922 * Proxy Settings:: How to get substitutes via proxy.
3923 * Substitution Failure:: What happens when substitution fails.
3924 * On Trusting Binaries:: How can you trust that binary blob?
3927 @node Official Substitute Servers
3928 @subsection Official Substitute Servers
3931 @code{@value{SUBSTITUTE-SERVER-1}} and
3932 @code{@value{SUBSTITUTE-SERVER-2}} are both front-ends to official build
3933 farms that build packages from Guix continuously for some architectures,
3934 and make them available as substitutes. These are the default source of
3935 substitutes; which can be overridden by passing the
3936 @option{--substitute-urls} option either to @command{guix-daemon}
3937 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3938 or to client tools such as @command{guix package}
3939 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3942 Substitute URLs can be either HTTP or HTTPS.
3943 HTTPS is recommended because communications are encrypted; conversely,
3944 using HTTP makes all communications visible to an eavesdropper, who
3945 could use the information gathered to determine, for instance, whether
3946 your system has unpatched security vulnerabilities.
3948 Substitutes from the official build farms are enabled by default when
3949 using Guix System (@pxref{GNU Distribution}). However,
3950 they are disabled by default when using Guix on a foreign distribution,
3951 unless you have explicitly enabled them via one of the recommended
3952 installation steps (@pxref{Installation}). The following paragraphs
3953 describe how to enable or disable substitutes for the official build
3954 farm; the same procedure can also be used to enable substitutes for any
3955 other substitute server.
3957 @node Substitute Server Authorization
3958 @subsection Substitute Server Authorization
3961 @cindex substitutes, authorization thereof
3962 @cindex access control list (ACL), for substitutes
3963 @cindex ACL (access control list), for substitutes
3964 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER-1}}, @code{@value{SUBSTITUTE-SERVER-2}} or a mirror, you
3965 must add the relevant public key to the access control list (ACL) of archive
3966 imports, using the @command{guix archive} command (@pxref{Invoking guix
3967 archive}). Doing so implies that you trust the substitute server to not
3968 be compromised and to serve genuine substitutes.
3971 If you are using Guix System, you can skip this section: Guix System
3972 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER-1}} and
3973 @code{@value{SUBSTITUTE-SERVER-2}} by default.
3976 The public keys for each of the project maintained substitute servers
3977 are installed along with Guix, in @code{@var{prefix}/share/guix/}, where
3978 @var{prefix} is the installation prefix of Guix. If you installed Guix
3979 from source, make sure you checked the GPG signature of
3980 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3981 Then, you can run something like this:
3984 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
3985 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
3988 Once this is in place, the output of a command like @code{guix build}
3989 should change from something like:
3992 $ guix build emacs --dry-run
3993 The following derivations would be built:
3994 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3995 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3996 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3997 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
4005 $ guix build emacs --dry-run
4006 112.3 MB would be downloaded:
4007 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
4008 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
4009 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
4010 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
4015 The text changed from ``The following derivations would be built'' to
4016 ``112.3 MB would be downloaded''. This indicates that substitutes from
4017 the configured substitute servers are usable and will be downloaded,
4018 when possible, for future builds.
4020 @cindex substitutes, how to disable
4021 The substitute mechanism can be disabled globally by running
4022 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
4023 guix-daemon}). It can also be disabled temporarily by passing the
4024 @option{--no-substitutes} option to @command{guix package},
4025 @command{guix build}, and other command-line tools.
4027 @node Getting Substitutes from Other Servers
4028 @subsection Getting Substitutes from Other Servers
4030 @cindex substitute servers, adding more
4031 Guix can look up and fetch substitutes from several servers. This is
4032 useful when you are using packages from additional channels for which
4033 the official server does not have substitutes but another server
4034 provides them. Another situation where this is useful is when you would
4035 prefer to download from your organization's substitute server, resorting
4036 to the official server only as a fallback or dismissing it altogether.
4038 You can give Guix a list of substitute server URLs and it will check
4039 them in the specified order. You also need to explicitly authorize the
4040 public keys of substitute servers to instruct Guix to accept the
4041 substitutes they sign.
4043 On Guix System, this is achieved by modifying the configuration of the
4044 @code{guix} service. Since the @code{guix} service is part of the
4045 default lists of services, @code{%base-services} and
4046 @code{%desktop-services}, you can use @code{modify-services} to change
4047 its configuration and add the URLs and substitute keys that you want
4048 (@pxref{Service Reference, @code{modify-services}}).
4050 As an example, suppose you want to fetch substitutes from
4051 @code{guix.example.org} and to authorize the signing key of that server,
4052 in addition to the default @code{@value{SUBSTITUTE-SERVER-1}} and
4053 @code{@value{SUBSTITUTE-SERVER-2}}. The resulting operating system
4054 configuration will look something like:
4060 ;; Assume we're starting from '%desktop-services'. Replace it
4061 ;; with the list of services you're actually using.
4062 (modify-services %desktop-services
4063 (guix-service-type config =>
4067 (append (list "https://guix.example.org")
4068 %default-substitute-urls))
4070 (append (list (local-file "./key.pub"))
4071 %default-authorized-guix-keys)))))))
4074 This assumes that the file @file{key.pub} contains the signing key of
4075 @code{guix.example.org}. With this change in place in your operating
4076 system configuration file (say @file{/etc/config.scm}), you can
4077 reconfigure and restart the @code{guix-daemon} service or reboot so the
4078 changes take effect:
4081 $ sudo guix system reconfigure /etc/config.scm
4082 $ sudo herd restart guix-daemon
4085 If you're running Guix on a ``foreign distro'', you would instead take
4086 the following steps to get substitutes from additional servers:
4090 Edit the service configuration file for @code{guix-daemon}; when using
4091 systemd, this is normally
4092 @file{/etc/systemd/system/guix-daemon.service}. Add the
4093 @option{--substitute-urls} option on the @command{guix-daemon} command
4094 line and list the URLs of interest (@pxref{daemon-substitute-urls,
4095 @code{guix-daemon --substitute-urls}}):
4098 @dots{} --substitute-urls='https://guix.example.org @value{SUBSTITUTE-URLS}'
4102 Restart the daemon. For systemd, it goes like this:
4105 systemctl daemon-reload
4106 systemctl restart guix-daemon.service
4110 Authorize the key of the new server (@pxref{Invoking guix archive}):
4113 guix archive --authorize < key.pub
4116 Again this assumes @file{key.pub} contains the public key that
4117 @code{guix.example.org} uses to sign substitutes.
4120 Now you're all set! Substitutes will be preferably taken from
4121 @code{https://guix.example.org}, using
4122 @code{@value{SUBSTITUTE-SERVER-1}} then
4123 @code{@value{SUBSTITUTE-SERVER-2}} as fallback options. Of course you
4124 can list as many substitute servers as you like, with the caveat that
4125 substitute lookup can be slowed down if too many servers need to be
4128 Note that there are also situations where one may want to add the URL of
4129 a substitute server @emph{without} authorizing its key.
4130 @xref{Substitute Authentication}, to understand this fine point.
4132 @node Substitute Authentication
4133 @subsection Substitute Authentication
4135 @cindex digital signatures
4136 Guix detects and raises an error when attempting to use a substitute
4137 that has been tampered with. Likewise, it ignores substitutes that are
4138 not signed, or that are not signed by one of the keys listed in the ACL.
4140 There is one exception though: if an unauthorized server provides
4141 substitutes that are @emph{bit-for-bit identical} to those provided by
4142 an authorized server, then the unauthorized server becomes eligible for
4143 downloads. For example, assume we have chosen two substitute servers
4147 --substitute-urls="https://a.example.org https://b.example.org"
4151 @cindex reproducible builds
4152 If the ACL contains only the key for @samp{b.example.org}, and if
4153 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
4154 then Guix will download substitutes from @samp{a.example.org} because it
4155 comes first in the list and can be considered a mirror of
4156 @samp{b.example.org}. In practice, independent build machines usually
4157 produce the same binaries, thanks to bit-reproducible builds (see
4160 When using HTTPS, the server's X.509 certificate is @emph{not} validated
4161 (in other words, the server is not authenticated), contrary to what
4162 HTTPS clients such as Web browsers usually do. This is because Guix
4163 authenticates substitute information itself, as explained above, which
4164 is what we care about (whereas X.509 certificates are about
4165 authenticating bindings between domain names and public keys).
4167 @node Proxy Settings
4168 @subsection Proxy Settings
4172 Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
4173 @env{https_proxy} environment variables can be set in the environment of
4174 @command{guix-daemon} and are honored for downloads of substitutes.
4175 Note that the value of those environment variables in the environment
4176 where @command{guix build}, @command{guix package}, and other client
4177 commands are run has @emph{absolutely no effect}.
4179 @node Substitution Failure
4180 @subsection Substitution Failure
4182 Even when a substitute for a derivation is available, sometimes the
4183 substitution attempt will fail. This can happen for a variety of
4184 reasons: the substitute server might be offline, the substitute may
4185 recently have been deleted, the connection might have been interrupted,
4188 When substitutes are enabled and a substitute for a derivation is
4189 available, but the substitution attempt fails, Guix will attempt to
4190 build the derivation locally depending on whether or not
4191 @option{--fallback} was given (@pxref{fallback-option,, common build
4192 option @option{--fallback}}). Specifically, if @option{--fallback} was
4193 omitted, then no local build will be performed, and the derivation is
4194 considered to have failed. However, if @option{--fallback} was given,
4195 then Guix will attempt to build the derivation locally, and the success
4196 or failure of the derivation depends on the success or failure of the
4197 local build. Note that when substitutes are disabled or no substitute
4198 is available for the derivation in question, a local build will
4199 @emph{always} be performed, regardless of whether or not
4200 @option{--fallback} was given.
4202 To get an idea of how many substitutes are available right now, you can
4203 try running the @command{guix weather} command (@pxref{Invoking guix
4204 weather}). This command provides statistics on the substitutes provided
4207 @node On Trusting Binaries
4208 @subsection On Trusting Binaries
4210 @cindex trust, of pre-built binaries
4211 Today, each individual's control over their own computing is at the
4212 mercy of institutions, corporations, and groups with enough power and
4213 determination to subvert the computing infrastructure and exploit its
4214 weaknesses. While using substitutes can be convenient, we encourage
4215 users to also build on their own, or even run their own build farm, such
4216 that the project run substitute servers are less of an interesting
4217 target. One way to help is by publishing the software you build using
4218 @command{guix publish} so that others have one more choice of server to
4219 download substitutes from (@pxref{Invoking guix publish}).
4221 Guix has the foundations to maximize build reproducibility
4222 (@pxref{Features}). In most cases, independent builds of a given
4223 package or derivation should yield bit-identical results. Thus, through
4224 a diverse set of independent package builds, we can strengthen the
4225 integrity of our systems. The @command{guix challenge} command aims to
4226 help users assess substitute servers, and to assist developers in
4227 finding out about non-deterministic package builds (@pxref{Invoking guix
4228 challenge}). Similarly, the @option{--check} option of @command{guix
4229 build} allows users to check whether previously-installed substitutes
4230 are genuine by rebuilding them locally (@pxref{build-check,
4231 @command{guix build --check}}).
4233 In the future, we want Guix to have support to publish and retrieve
4234 binaries to/from other users, in a peer-to-peer fashion. If you would
4235 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
4237 @node Packages with Multiple Outputs
4238 @section Packages with Multiple Outputs
4240 @cindex multiple-output packages
4241 @cindex package outputs
4244 Often, packages defined in Guix have a single @dfn{output}---i.e., the
4245 source package leads to exactly one directory in the store. When running
4246 @command{guix install glibc}, one installs the default output of the
4247 GNU libc package; the default output is called @code{out}, but its name
4248 can be omitted as shown in this command. In this particular case, the
4249 default output of @code{glibc} contains all the C header files, shared
4250 libraries, static libraries, Info documentation, and other supporting
4253 Sometimes it is more appropriate to separate the various types of files
4254 produced from a single source package into separate outputs. For
4255 instance, the GLib C library (used by GTK+ and related packages)
4256 installs more than 20 MiB of reference documentation as HTML pages.
4257 To save space for users who do not need it, the documentation goes to a
4258 separate output, called @code{doc}. To install the main GLib output,
4259 which contains everything but the documentation, one would run:
4265 @cindex documentation
4266 The command to install its documentation is:
4269 guix install glib:doc
4272 Some packages install programs with different ``dependency footprints''.
4273 For instance, the WordNet package installs both command-line tools and
4274 graphical user interfaces (GUIs). The former depend solely on the C
4275 library, whereas the latter depend on Tcl/Tk and the underlying X
4276 libraries. In this case, we leave the command-line tools in the default
4277 output, whereas the GUIs are in a separate output. This allows users
4278 who do not need the GUIs to save space. The @command{guix size} command
4279 can help find out about such situations (@pxref{Invoking guix size}).
4280 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
4282 There are several such multiple-output packages in the GNU distribution.
4283 Other conventional output names include @code{lib} for libraries and
4284 possibly header files, @code{bin} for stand-alone programs, and
4285 @code{debug} for debugging information (@pxref{Installing Debugging
4286 Files}). The outputs of a packages are listed in the third column of
4287 the output of @command{guix package --list-available} (@pxref{Invoking
4291 @node Invoking guix gc
4292 @section Invoking @command{guix gc}
4294 @cindex garbage collector
4296 Packages that are installed, but not used, may be @dfn{garbage-collected}.
4297 The @command{guix gc} command allows users to explicitly run the garbage
4298 collector to reclaim space from the @file{/gnu/store} directory. It is
4299 the @emph{only} way to remove files from @file{/gnu/store}---removing
4300 files or directories manually may break it beyond repair!
4303 @cindex garbage collector roots
4304 The garbage collector has a set of known @dfn{roots}: any file under
4305 @file{/gnu/store} reachable from a root is considered @dfn{live} and
4306 cannot be deleted; any other file is considered @dfn{dead} and may be
4307 deleted. The set of garbage collector roots (``GC roots'' for short)
4308 includes default user profiles; by default, the symlinks under
4309 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
4310 added with @command{guix build --root}, for example (@pxref{Invoking
4311 guix build}). The @command{guix gc --list-roots} command lists them.
4313 Prior to running @code{guix gc --collect-garbage} to make space, it is
4314 often useful to remove old generations from user profiles; that way, old
4315 package builds referenced by those generations can be reclaimed. This
4316 is achieved by running @code{guix package --delete-generations}
4317 (@pxref{Invoking guix package}).
4319 Our recommendation is to run a garbage collection periodically, or when
4320 you are short on disk space. For instance, to guarantee that at least
4321 5@tie{}GB are available on your disk, simply run:
4327 It is perfectly safe to run as a non-interactive periodic job
4328 (@pxref{Scheduled Job Execution}, for how to set up such a job).
4329 Running @command{guix gc} with no arguments will collect as
4330 much garbage as it can, but that is often inconvenient: you may find
4331 yourself having to rebuild or re-download software that is ``dead'' from
4332 the GC viewpoint but that is necessary to build other pieces of
4333 software---e.g., the compiler tool chain.
4335 The @command{guix gc} command has three modes of operation: it can be
4336 used to garbage-collect any dead files (the default), to delete specific
4337 files (the @option{--delete} option), to print garbage-collector
4338 information, or for more advanced queries. The garbage collection
4339 options are as follows:
4342 @item --collect-garbage[=@var{min}]
4343 @itemx -C [@var{min}]
4344 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4345 sub-directories. This is the default operation when no option is
4348 When @var{min} is given, stop once @var{min} bytes have been collected.
4349 @var{min} may be a number of bytes, or it may include a unit as a
4350 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4351 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4353 When @var{min} is omitted, collect all the garbage.
4355 @item --free-space=@var{free}
4356 @itemx -F @var{free}
4357 Collect garbage until @var{free} space is available under
4358 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4359 as @code{500MiB}, as described above.
4361 When @var{free} or more is already available in @file{/gnu/store}, do
4362 nothing and exit immediately.
4364 @item --delete-generations[=@var{duration}]
4365 @itemx -d [@var{duration}]
4366 Before starting the garbage collection process, delete all the generations
4367 older than @var{duration}, for all the user profiles and home environment
4368 generations; when run as root, this
4369 applies to all the profiles @emph{of all the users}.
4371 For example, this command deletes all the generations of all your profiles
4372 that are older than 2 months (except generations that are current), and then
4373 proceeds to free space until at least 10 GiB are available:
4376 guix gc -d 2m -F 10G
4381 Attempt to delete all the store files and directories specified as
4382 arguments. This fails if some of the files are not in the store, or if
4383 they are still live.
4385 @item --list-failures
4386 List store items corresponding to cached build failures.
4388 This prints nothing unless the daemon was started with
4389 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4390 @option{--cache-failures}}).
4393 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4397 List store items in use by currently running processes. These store
4398 items are effectively considered GC roots: they cannot be deleted.
4400 @item --clear-failures
4401 Remove the specified store items from the failed-build cache.
4403 Again, this option only makes sense when the daemon is started with
4404 @option{--cache-failures}. Otherwise, it does nothing.
4407 Show the list of dead files and directories still present in the
4408 store---i.e., files and directories no longer reachable from any root.
4411 Show the list of live store files and directories.
4415 In addition, the references among existing store files can be queried:
4421 @cindex package dependencies
4422 List the references (respectively, the referrers) of store files given
4428 List the requisites of the store files passed as arguments. Requisites
4429 include the store files themselves, their references, and the references
4430 of these, recursively. In other words, the returned list is the
4431 @dfn{transitive closure} of the store files.
4433 @xref{Invoking guix size}, for a tool to profile the size of the closure
4434 of an element. @xref{Invoking guix graph}, for a tool to visualize
4435 the graph of references.
4439 Return the derivation(s) leading to the given store items
4440 (@pxref{Derivations}).
4442 For example, this command:
4445 guix gc --derivers $(guix package -I ^emacs$ | cut -f4)
4449 returns the @file{.drv} file(s) leading to the @code{emacs} package
4450 installed in your profile.
4452 Note that there may be zero matching @file{.drv} files, for instance
4453 because these files have been garbage-collected. There can also be more
4454 than one matching @file{.drv} due to fixed-output derivations.
4457 Lastly, the following options allow you to check the integrity of the
4458 store and to control disk usage.
4462 @item --verify[=@var{options}]
4463 @cindex integrity, of the store
4464 @cindex integrity checking
4465 Verify the integrity of the store.
4467 By default, make sure that all the store items marked as valid in the
4468 database of the daemon actually exist in @file{/gnu/store}.
4470 When provided, @var{options} must be a comma-separated list containing one
4471 or more of @code{contents} and @code{repair}.
4473 When passing @option{--verify=contents}, the daemon computes the
4474 content hash of each store item and compares it against its hash in the
4475 database. Hash mismatches are reported as data corruptions. Because it
4476 traverses @emph{all the files in the store}, this command can take a
4477 long time, especially on systems with a slow disk drive.
4479 @cindex repairing the store
4480 @cindex corruption, recovering from
4481 Using @option{--verify=repair} or @option{--verify=contents,repair}
4482 causes the daemon to try to repair corrupt store items by fetching
4483 substitutes for them (@pxref{Substitutes}). Because repairing is not
4484 atomic, and thus potentially dangerous, it is available only to the
4485 system administrator. A lightweight alternative, when you know exactly
4486 which items in the store are corrupt, is @command{guix build --repair}
4487 (@pxref{Invoking guix build}).
4490 @cindex deduplication
4491 Optimize the store by hard-linking identical files---this is
4492 @dfn{deduplication}.
4494 The daemon performs deduplication after each successful build or archive
4495 import, unless it was started with @option{--disable-deduplication}
4496 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4497 this option is primarily useful when the daemon was running with
4498 @option{--disable-deduplication}.
4502 @node Invoking guix pull
4503 @section Invoking @command{guix pull}
4505 @cindex upgrading Guix
4506 @cindex updating Guix
4507 @cindex @command{guix pull}
4509 @cindex security, @command{guix pull}
4510 @cindex authenticity, of code obtained with @command{guix pull}
4511 Packages are installed or upgraded to the latest version available in
4512 the distribution currently available on your local machine. To update
4513 that distribution, along with the Guix tools, you must run @command{guix
4514 pull}: the command downloads the latest Guix source code and package
4515 descriptions, and deploys it. Source code is downloaded from a
4516 @uref{https://git-scm.com, Git} repository, by default the official
4517 GNU@tie{}Guix repository, though this can be customized. @command{guix
4518 pull} ensures that the code it downloads is @emph{authentic} by
4519 verifying that commits are signed by Guix developers.
4521 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4522 (@pxref{Channels}) specified by one of the followings, in this order:
4526 the @option{--channels} option;
4528 the user's @file{~/.config/guix/channels.scm} file;
4530 the system-wide @file{/etc/guix/channels.scm} file;
4532 the built-in default channels specified in the @code{%default-channels}
4536 On completion, @command{guix package} will use packages and package
4537 versions from this just-retrieved copy of Guix. Not only that, but all
4538 the Guix commands and Scheme modules will also be taken from that latest
4539 version. New @command{guix} sub-commands added by the update also
4542 Any user can update their Guix copy using @command{guix pull}, and the
4543 effect is limited to the user who ran @command{guix pull}. For
4544 instance, when user @code{root} runs @command{guix pull}, this has no
4545 effect on the version of Guix that user @code{alice} sees, and vice
4548 The result of running @command{guix pull} is a @dfn{profile} available
4549 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4550 make sure to add it to the beginning of your search path so that you use
4551 the latest version, and similarly for the Info manual
4552 (@pxref{Documentation}):
4555 export PATH="$HOME/.config/guix/current/bin:$PATH"
4556 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4559 The @option{--list-generations} or @option{-l} option lists past generations
4560 produced by @command{guix pull}, along with details about their provenance:
4564 Generation 1 Jun 10 2018 00:18:18
4566 repository URL: https://git.savannah.gnu.org/git/guix.git
4567 branch: origin/master
4568 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4570 Generation 2 Jun 11 2018 11:02:49
4572 repository URL: https://git.savannah.gnu.org/git/guix.git
4573 branch: origin/master
4574 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4576 Generation 3 Jun 13 2018 23:31:07 (current)
4578 repository URL: https://git.savannah.gnu.org/git/guix.git
4579 branch: origin/master
4580 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4583 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4584 describe the current status of Guix.
4586 This @code{~/.config/guix/current} profile works exactly like the profiles
4587 created by @command{guix package} (@pxref{Invoking guix package}). That
4588 is, you can list generations, roll back to the previous
4589 generation---i.e., the previous Guix---and so on:
4592 $ guix pull --roll-back
4593 switched from generation 3 to 2
4594 $ guix pull --delete-generations=1
4595 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4598 You can also use @command{guix package} (@pxref{Invoking guix package})
4599 to manage the profile by naming it explicitly:
4601 $ guix package -p ~/.config/guix/current --roll-back
4602 switched from generation 3 to 2
4603 $ guix package -p ~/.config/guix/current --delete-generations=1
4604 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4607 The @command{guix pull} command is usually invoked with no arguments,
4608 but it supports the following options:
4611 @item --url=@var{url}
4612 @itemx --commit=@var{commit}
4613 @itemx --branch=@var{branch}
4614 Download code for the @code{guix} channel from the specified @var{url}, at the
4615 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4616 string), or @var{branch}.
4618 @cindex @file{channels.scm}, configuration file
4619 @cindex configuration file for channels
4620 These options are provided for convenience, but you can also specify your
4621 configuration in the @file{~/.config/guix/channels.scm} file or using the
4622 @option{--channels} option (see below).
4624 @item --channels=@var{file}
4625 @itemx -C @var{file}
4626 Read the list of channels from @var{file} instead of
4627 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4628 @var{file} must contain Scheme code that
4629 evaluates to a list of channel objects. @xref{Channels}, for more
4632 @cindex channel news
4635 Display news written by channel authors for their users for changes made
4636 since the previous generation (@pxref{Channels, Writing Channel News}).
4637 When @option{--details} is passed, additionally display new and upgraded
4640 You can view that information for previous generations with
4641 @command{guix pull -l}.
4643 @item --list-generations[=@var{pattern}]
4644 @itemx -l [@var{pattern}]
4645 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4646 is provided, the subset of generations that match @var{pattern}.
4647 The syntax of @var{pattern} is the same as with @code{guix package
4648 --list-generations} (@pxref{Invoking guix package}).
4650 By default, this prints information about the channels used in each
4651 revision as well as the corresponding news entries. If you pass
4652 @option{--details}, it will also print the list of packages added and
4653 upgraded in each generation compared to the previous one.
4656 Instruct @option{--list-generations} or @option{--news} to display more
4657 information about the differences between subsequent generations---see
4661 @cindex rolling back
4662 @cindex undoing transactions
4663 @cindex transactions, undoing
4664 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4665 undo the last transaction.
4667 @item --switch-generation=@var{pattern}
4668 @itemx -S @var{pattern}
4670 Switch to a particular generation defined by @var{pattern}.
4672 @var{pattern} may be either a generation number or a number prefixed
4673 with ``+'' or ``-''. The latter means: move forward/backward by a
4674 specified number of generations. For example, if you want to return to
4675 the latest generation after @option{--roll-back}, use
4676 @option{--switch-generation=+1}.
4678 @item --delete-generations[=@var{pattern}]
4679 @itemx -d [@var{pattern}]
4680 When @var{pattern} is omitted, delete all generations except the current
4683 This command accepts the same patterns as @option{--list-generations}.
4684 When @var{pattern} is specified, delete the matching generations. When
4685 @var{pattern} specifies a duration, generations @emph{older} than the
4686 specified duration match. For instance, @option{--delete-generations=1m}
4687 deletes generations that are more than one month old.
4689 If the current generation matches, it is @emph{not} deleted.
4691 Note that deleting generations prevents rolling back to them.
4692 Consequently, this command must be used with care.
4694 @xref{Invoking guix describe}, for a way to display information about the
4695 current generation only.
4697 @item --profile=@var{profile}
4698 @itemx -p @var{profile}
4699 Use @var{profile} instead of @file{~/.config/guix/current}.
4703 Show which channel commit(s) would be used and what would be built or
4704 substituted but do not actually do it.
4706 @item --allow-downgrades
4707 Allow pulling older or unrelated revisions of channels than those
4710 @cindex downgrade attacks, protection against
4711 By default, @command{guix pull} protects against so-called ``downgrade
4712 attacks'' whereby the Git repository of a channel would be reset to an
4713 earlier or unrelated revision of itself, potentially leading you to
4714 install older, known-vulnerable versions of software packages.
4717 Make sure you understand its security implications before using
4718 @option{--allow-downgrades}.
4721 @item --disable-authentication
4722 Allow pulling channel code without authenticating it.
4724 @cindex authentication, of channel code
4725 By default, @command{guix pull} authenticates code downloaded from
4726 channels by verifying that its commits are signed by authorized
4727 developers, and raises an error if this is not the case. This option
4728 instructs it to not perform any such verification.
4731 Make sure you understand its security implications before using
4732 @option{--disable-authentication}.
4735 @item --system=@var{system}
4736 @itemx -s @var{system}
4737 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4738 the system type of the build host.
4741 Use the bootstrap Guile to build the latest Guix. This option is only
4742 useful to Guix developers.
4745 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4746 repository and branch to pull from, as well as @emph{additional} repositories
4747 containing package modules that should be deployed. @xref{Channels}, for more
4750 In addition, @command{guix pull} supports all the common build options
4751 (@pxref{Common Build Options}).
4753 @node Invoking guix time-machine
4754 @section Invoking @command{guix time-machine}
4756 @cindex @command{guix time-machine}
4757 @cindex pinning, channels
4758 @cindex replicating Guix
4759 @cindex reproducibility, of Guix
4761 The @command{guix time-machine} command provides access to other
4762 revisions of Guix, for example to install older versions of packages,
4763 or to reproduce a computation in an identical environment. The revision
4764 of Guix to be used is defined by a commit or by a channel
4765 description file created by @command{guix describe}
4766 (@pxref{Invoking guix describe}).
4768 The general syntax is:
4771 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4774 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4775 @command{guix} command of the specified revision. The @var{options} that define
4776 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4779 @item --url=@var{url}
4780 @itemx --commit=@var{commit}
4781 @itemx --branch=@var{branch}
4782 Use the @code{guix} channel from the specified @var{url}, at the
4783 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4784 string), or @var{branch}.
4786 @item --channels=@var{file}
4787 @itemx -C @var{file}
4788 Read the list of channels from @var{file}. @var{file} must contain
4789 Scheme code that evaluates to a list of channel objects.
4790 @xref{Channels} for more information.
4793 As for @command{guix pull}, the absence of any options means that the
4794 latest commit on the master branch will be used. The command
4797 guix time-machine -- build hello
4800 will thus build the package @code{hello} as defined in the master branch,
4801 which is in general a newer revision of Guix than you have installed.
4802 Time travel works in both directions!
4804 Note that @command{guix time-machine} can trigger builds of channels and
4805 their dependencies, and these are controlled by the standard build
4806 options (@pxref{Common Build Options}).
4811 @c TODO: Remove this once we're more confident about API stability.
4813 The functionality described here is a ``technology preview'' as of version
4814 @value{VERSION}. As such, the interface is subject to change.
4818 @cindex composition of Guix revisions
4819 Sometimes you might need to mix packages from the revision of Guix you're
4820 currently running with packages available in a different revision of Guix.
4821 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4822 revisions in arbitrary ways.
4824 @cindex inferior packages
4825 Technically, an ``inferior'' is essentially a separate Guix process connected
4826 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4827 @code{(guix inferior)} module allows you to create inferiors and to
4828 communicate with them. It also provides a high-level interface to browse and
4829 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4831 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4832 to interact with a separate revision of Guix. For example, let's assume you
4833 want to install in your profile the current @code{guile} package, along with
4834 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4835 because the newer @code{guile-json} has an incompatible API and you want to
4836 run your code against the old API@. To do that, you could write a manifest for
4837 use by @code{guix package --manifest} (@pxref{Writing Manifests}); in that
4838 manifest, you would create an inferior for that old Guix revision you care
4839 about, and you would look up the @code{guile-json} package in the inferior:
4842 (use-modules (guix inferior) (guix channels)
4843 (srfi srfi-1)) ;for 'first'
4846 ;; This is the old revision from which we want to
4847 ;; extract guile-json.
4850 (url "https://git.savannah.gnu.org/git/guix.git")
4852 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4855 ;; An inferior representing the above revision.
4856 (inferior-for-channels channels))
4858 ;; Now create a manifest with the current "guile" package
4859 ;; and the old "guile-json" package.
4861 (list (first (lookup-inferior-packages inferior "guile-json"))
4862 (specification->package "guile")))
4865 On its first run, @command{guix package --manifest} might have to build the
4866 channel you specified before it can create the inferior; subsequent runs will
4867 be much faster because the Guix revision will be cached.
4869 The @code{(guix inferior)} module provides the following procedures to open an
4872 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4873 [#:cache-directory] [#:ttl]
4874 Return an inferior for @var{channels}, a list of channels. Use the cache at
4875 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4876 This procedure opens a new connection to the build daemon.
4878 As a side effect, this procedure may build or substitute binaries for
4879 @var{channels}, which can take time.
4882 @deffn {Scheme Procedure} open-inferior @var{directory} @
4883 [#:command "bin/guix"]
4884 Open the inferior Guix in @var{directory}, running
4885 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4886 the inferior could not be launched.
4889 @cindex inferior packages
4890 The procedures listed below allow you to obtain and manipulate inferior
4893 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4894 Return the list of packages known to @var{inferior}.
4897 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4899 Return the sorted list of inferior packages matching @var{name} in
4900 @var{inferior}, with highest version numbers first. If @var{version} is true,
4901 return only packages with a version number prefixed by @var{version}.
4904 @deffn {Scheme Procedure} inferior-package? @var{obj}
4905 Return true if @var{obj} is an inferior package.
4908 @deffn {Scheme Procedure} inferior-package-name @var{package}
4909 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4910 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4911 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4912 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4913 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4914 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4915 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4916 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4917 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4918 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4919 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4920 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4921 These procedures are the counterpart of package record accessors
4922 (@pxref{package Reference}). Most of them work by querying the inferior
4923 @var{package} comes from, so the inferior must still be live when you call
4927 Inferior packages can be used transparently like any other package or
4928 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4929 transparently handled by the @code{packages->manifest} procedure, which is
4930 commonly used in manifests (@pxref{Invoking guix package, the
4931 @option{--manifest} option of @command{guix package}}). Thus you can insert
4932 an inferior package pretty much anywhere you would insert a regular package:
4933 in manifests, in the @code{packages} field of your @code{operating-system}
4934 declaration, and so on.
4936 @node Invoking guix describe
4937 @section Invoking @command{guix describe}
4939 @cindex reproducibility
4940 @cindex replicating Guix
4941 Often you may want to answer questions like: ``Which revision of Guix am I
4942 using?'' or ``Which channels am I using?'' This is useful information in many
4943 situations: if you want to @emph{replicate} an environment on a different
4944 machine or user account, if you want to report a bug or to determine what
4945 change in the channels you are using caused it, or if you want to record your
4946 system state for reproducibility purposes. The @command{guix describe}
4947 command answers these questions.
4949 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4950 displays the channel(s) that it was built from, including their repository URL
4951 and commit IDs (@pxref{Channels}):
4955 Generation 10 Sep 03 2018 17:32:44 (current)
4957 repository URL: https://git.savannah.gnu.org/git/guix.git
4959 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4962 If you're familiar with the Git version control system, this is similar in
4963 spirit to @command{git describe}; the output is also similar to that of
4964 @command{guix pull --list-generations}, but limited to the current generation
4965 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4966 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4967 information is all it takes to describe the revision of Guix you're using, and
4968 also to replicate it.
4970 To make it easier to replicate Guix, @command{guix describe} can also be asked
4971 to return a list of channels instead of the human-readable description above:
4974 $ guix describe -f channels
4977 (url "https://git.savannah.gnu.org/git/guix.git")
4979 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4981 (make-channel-introduction
4982 "9edb3f66fd807b096b48283debdcddccfea34bad"
4983 (openpgp-fingerprint
4984 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4988 You can save this to a file and feed it to @command{guix pull -C} on some
4989 other machine or at a later point in time, which will instantiate @emph{this
4990 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4991 From there on, since you're able to deploy the same revision of Guix, you can
4992 just as well @emph{replicate a complete software environment}. We humbly
4993 think that this is @emph{awesome}, and we hope you'll like it too!
4995 The details of the options supported by @command{guix describe} are as
4999 @item --format=@var{format}
5000 @itemx -f @var{format}
5001 Produce output in the specified @var{format}, one of:
5005 produce human-readable output;
5007 produce a list of channel specifications that can be passed to @command{guix
5008 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
5010 @item channels-sans-intro
5011 like @code{channels}, but omit the @code{introduction} field; use it to
5012 produce a channel specification suitable for Guix version 1.1.0 or
5013 earlier---the @code{introduction} field has to do with channel
5014 authentication (@pxref{Channels, Channel Authentication}) and is not
5015 supported by these older versions;
5018 produce a list of channel specifications in JSON format;
5020 produce a list of channel specifications in Recutils format.
5023 @item --list-formats
5024 Display available formats for @option{--format} option.
5026 @item --profile=@var{profile}
5027 @itemx -p @var{profile}
5028 Display information about @var{profile}.
5031 @node Invoking guix archive
5032 @section Invoking @command{guix archive}
5034 @cindex @command{guix archive}
5036 The @command{guix archive} command allows users to @dfn{export} files
5037 from the store into a single archive, and to later @dfn{import} them on
5038 a machine that runs Guix.
5039 In particular, it allows store files to be transferred from one machine
5040 to the store on another machine.
5043 If you're looking for a way to produce archives in a format suitable for
5044 tools other than Guix, @pxref{Invoking guix pack}.
5047 @cindex exporting store items
5048 To export store files as an archive to standard output, run:
5051 guix archive --export @var{options} @var{specifications}...
5054 @var{specifications} may be either store file names or package
5055 specifications, as for @command{guix package} (@pxref{Invoking guix
5056 package}). For instance, the following command creates an archive
5057 containing the @code{gui} output of the @code{git} package and the main
5058 output of @code{emacs}:
5061 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
5064 If the specified packages are not built yet, @command{guix archive}
5065 automatically builds them. The build process may be controlled with the
5066 common build options (@pxref{Common Build Options}).
5068 To transfer the @code{emacs} package to a machine connected over SSH,
5072 guix archive --export -r emacs | ssh the-machine guix archive --import
5076 Similarly, a complete user profile may be transferred from one machine
5077 to another like this:
5080 guix archive --export -r $(readlink -f ~/.guix-profile) | \
5081 ssh the-machine guix archive --import
5085 However, note that, in both examples, all of @code{emacs} and the
5086 profile as well as all of their dependencies are transferred (due to
5087 @option{-r}), regardless of what is already available in the store on
5088 the target machine. The @option{--missing} option can help figure out
5089 which items are missing from the target store. The @command{guix copy}
5090 command simplifies and optimizes this whole process, so this is probably
5091 what you should use in this case (@pxref{Invoking guix copy}).
5093 @cindex nar, archive format
5094 @cindex normalized archive (nar)
5095 @cindex nar bundle, archive format
5096 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
5097 format (described below), and the output of @command{guix archive
5098 --export} (and input of @command{guix archive --import}) is a @dfn{nar
5102 comparable in spirit to `tar', but with differences
5103 that make it more appropriate for our purposes. First, rather than
5104 recording all Unix metadata for each file, the nar format only mentions
5105 the file type (regular, directory, or symbolic link); Unix permissions
5106 and owner/group are dismissed. Second, the order in which directory
5107 entries are stored always follows the order of file names according to
5108 the C locale collation order. This makes archive production fully
5111 That nar bundle format is essentially the concatenation of zero or more
5112 nars along with metadata for each store item it contains: its file name,
5113 references, corresponding derivation, and a digital signature.
5115 When exporting, the daemon digitally signs the contents of the archive,
5116 and that digital signature is appended. When importing, the daemon
5117 verifies the signature and rejects the import in case of an invalid
5118 signature or if the signing key is not authorized.
5119 @c FIXME: Add xref to daemon doc about signatures.
5121 The main options are:
5125 Export the specified store files or packages (see below). Write the
5126 resulting archive to the standard output.
5128 Dependencies are @emph{not} included in the output, unless
5129 @option{--recursive} is passed.
5133 When combined with @option{--export}, this instructs @command{guix archive}
5134 to include dependencies of the given items in the archive. Thus, the
5135 resulting archive is self-contained: it contains the closure of the
5136 exported store items.
5139 Read an archive from the standard input, and import the files listed
5140 therein into the store. Abort if the archive has an invalid digital
5141 signature, or if it is signed by a public key not among the authorized
5142 keys (see @option{--authorize} below).
5145 Read a list of store file names from the standard input, one per line,
5146 and write on the standard output the subset of these files missing from
5149 @item --generate-key[=@var{parameters}]
5150 @cindex signing, archives
5151 Generate a new key pair for the daemon. This is a prerequisite before
5152 archives can be exported with @option{--export}. This
5153 operation is usually instantaneous but it can take time if the system's
5154 entropy pool needs to be refilled. On Guix System,
5155 @code{guix-service-type} takes care of generating this key pair the
5158 The generated key pair is typically stored under @file{/etc/guix}, in
5159 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
5160 key, which must be kept secret). When @var{parameters} is omitted,
5161 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
5162 versions before 1.6.0, it is a 4096-bit RSA key.
5163 Alternatively, @var{parameters} can specify
5164 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
5165 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
5166 Libgcrypt Reference Manual}).
5169 @cindex authorizing, archives
5170 Authorize imports signed by the public key passed on standard input.
5171 The public key must be in ``s-expression advanced format''---i.e., the
5172 same format as the @file{signing-key.pub} file.
5174 The list of authorized keys is kept in the human-editable file
5175 @file{/etc/guix/acl}. The file contains
5176 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
5177 s-expressions''} and is structured as an access-control list in the
5178 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
5181 @item --extract=@var{directory}
5182 @itemx -x @var{directory}
5183 Read a single-item archive as served by substitute servers
5184 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
5185 low-level operation needed in only very narrow use cases; see below.
5187 For example, the following command extracts the substitute for Emacs
5188 served by @code{@value{SUBSTITUTE-SERVER-1}} to @file{/tmp/emacs}:
5192 https://@value{SUBSTITUTE-SERVER-1}/nar/gzip/@dots{}-emacs-24.5 \
5193 | gunzip | guix archive -x /tmp/emacs
5196 Single-item archives are different from multiple-item archives produced
5197 by @command{guix archive --export}; they contain a single store item,
5198 and they do @emph{not} embed a signature. Thus this operation does
5199 @emph{no} signature verification and its output should be considered
5202 The primary purpose of this operation is to facilitate inspection of
5203 archive contents coming from possibly untrusted substitute servers
5204 (@pxref{Invoking guix challenge}).
5208 Read a single-item archive as served by substitute servers
5209 (@pxref{Substitutes}) and print the list of files it contains, as in
5214 https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-emacs-26.3 \
5215 | lzip -d | guix archive -t
5220 @c *********************************************************************
5225 @cindex @file{channels.scm}, configuration file
5226 @cindex configuration file for channels
5227 @cindex @command{guix pull}, configuration file
5228 @cindex configuration of @command{guix pull}
5229 Guix and its package collection are updated by running @command{guix pull}
5230 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
5231 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
5232 customized by defining @dfn{channels} in the
5233 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
5234 of a Git repository to be deployed, and @command{guix pull} can be instructed
5235 to pull from one or more channels. In other words, channels can be used
5236 to @emph{customize} and to @emph{extend} Guix, as we will see below.
5237 Guix is able to take into account security concerns and deal with authenticated
5241 * Specifying Additional Channels:: Extending the package collection.
5242 * Using a Custom Guix Channel:: Using a customized Guix.
5243 * Replicating Guix:: Running the @emph{exact same} Guix.
5244 * Channel Authentication:: How Guix verifies what it fetches.
5245 * Channels with Substitutes:: Using channels with available substitutes.
5246 * Creating a Channel:: How to write your custom channel.
5247 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
5248 * Declaring Channel Dependencies:: How to depend on other channels.
5249 * Specifying Channel Authorizations:: Defining channel authors authorizations.
5250 * Primary URL:: Distinguishing mirror to original.
5251 * Writing Channel News:: Communicating information to channel's users.
5254 @node Specifying Additional Channels
5255 @section Specifying Additional Channels
5257 @cindex extending the package collection (channels)
5258 @cindex variant packages (channels)
5259 You can specify @emph{additional channels} to pull from. To use a channel, write
5260 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
5261 @emph{in addition} to the default Guix channel(s):
5263 @vindex %default-channels
5265 ;; Add variant packages to those Guix provides.
5267 (name 'variant-packages)
5268 (url "https://example.org/variant-packages.git"))
5273 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
5274 add a channel the list of channels that the variable @code{%default-channels}
5275 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
5276 Manual}). With this file in place, @command{guix pull} builds not only Guix
5277 but also the package modules from your own repository. The result in
5278 @file{~/.config/guix/current} is the union of Guix with your own package
5283 Generation 19 Aug 27 2018 16:20:48
5285 repository URL: https://git.savannah.gnu.org/git/guix.git
5287 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
5288 variant-packages dd3df5e
5289 repository URL: https://example.org/variant-packages.git
5291 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
5295 The output of @command{guix describe} above shows that we're now running
5296 Generation@tie{}19 and that it includes
5297 both Guix and packages from the @code{variant-personal-packages} channel
5298 (@pxref{Invoking guix describe}).
5300 @node Using a Custom Guix Channel
5301 @section Using a Custom Guix Channel
5303 The channel called @code{guix} specifies where Guix itself---its command-line
5304 tools as well as its package collection---should be downloaded. For instance,
5305 suppose you want to update from another copy of the Guix repository at
5306 @code{example.org}, and specifically the @code{super-hacks} branch, you can
5307 write in @code{~/.config/guix/channels.scm} this specification:
5310 ;; Tell 'guix pull' to use another repo.
5313 (url "https://example.org/another-guix.git")
5314 (branch "super-hacks")))
5318 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
5319 branch of the repository at @code{example.org}. The authentication concern is
5320 addressed below (@pxref{Channel Authentication}).
5322 @node Replicating Guix
5323 @section Replicating Guix
5325 @cindex pinning, channels
5326 @cindex replicating Guix
5327 @cindex reproducibility, of Guix
5328 The @command{guix describe} command shows precisely which commits were
5329 used to build the instance of Guix we're using (@pxref{Invoking guix
5330 describe}). We can replicate this instance on another machine or at a
5331 different point in time by providing a channel specification ``pinned''
5332 to these commits that looks like this:
5335 ;; Deploy specific commits of my channels of interest.
5338 (url "https://git.savannah.gnu.org/git/guix.git")
5339 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5341 (name 'variant-packages)
5342 (url "https://example.org/variant-packages.git")
5343 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5346 To obtain this pinned channel specification, the easiest way is to run
5347 @command{guix describe} and to save its output in the @code{channels}
5348 format in a file, like so:
5351 guix describe -f channels > channels.scm
5354 The resulting @file{channels.scm} file can be passed to the @option{-C}
5355 option of @command{guix pull} (@pxref{Invoking guix pull}) or
5356 @command{guix time-machine} (@pxref{Invoking guix time-machine}), as in
5360 guix time-machine -C channels.scm -- shell python -- python3
5363 Given the @file{channels.scm} file, the command above will always fetch
5364 the @emph{exact same Guix instance}, then use that instance to run the
5365 exact same Python (@pxref{Invoking guix shell}). On any machine, at any
5366 time, it ends up running the exact same binaries, bit for bit.
5369 Pinned channels address a problem similar to ``lock files'' as
5370 implemented by some deployment tools---they let you pin and reproduce a
5371 set of packages. In the case of Guix though, you are effectively
5372 pinning the entire package set as defined at the given channel commits;
5373 in fact, you are pinning all of Guix, including its core modules and
5374 command-line tools. You're also getting strong guarantees that you are,
5375 indeed, obtaining the exact same software.
5377 This gives you super powers, allowing you to track the provenance of binary
5378 artifacts with very fine grain, and to reproduce software environments at
5379 will---some sort of ``meta reproducibility'' capabilities, if you will.
5380 @xref{Inferiors}, for another way to take advantage of these super powers.
5382 @node Channel Authentication
5383 @section Channel Authentication
5385 @anchor{channel-authentication}
5386 @cindex authentication, of channel code
5387 The @command{guix pull} and @command{guix time-machine} commands
5388 @dfn{authenticate} the code retrieved from channels: they make sure each
5389 commit that is fetched is signed by an authorized developer. The goal
5390 is to protect from unauthorized modifications to the channel that would
5391 lead users to run malicious code.
5393 As a user, you must provide a @dfn{channel introduction} in your
5394 channels file so that Guix knows how to authenticate its first commit.
5395 A channel specification, including its introduction, looks something
5400 (name 'some-channel)
5401 (url "https://example.org/some-channel.git")
5403 (make-channel-introduction
5404 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5405 (openpgp-fingerprint
5406 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5409 The specification above shows the name and URL of the channel. The call
5410 to @code{make-channel-introduction} above specifies that authentication
5411 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5412 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5414 For the main channel, called @code{guix}, you automatically get that
5415 information from your Guix installation. For other channels, include
5416 the channel introduction provided by the channel authors in your
5417 @file{channels.scm} file. Make sure you retrieve the channel
5418 introduction from a trusted source since that is the root of your trust.
5420 If you're curious about the authentication mechanics, read on!
5422 @node Channels with Substitutes
5423 @section Channels with Substitutes
5425 When running @command{guix pull}, Guix will first compile the
5426 definitions of every available package. This is an expensive operation
5427 for which substitutes (@pxref{Substitutes}) may be available. The
5428 following snippet in @file{channels.scm} will ensure that @command{guix
5429 pull} uses the latest commit with available substitutes for the package
5430 definitions: this is done by querying the continuous integration
5431 server at @url{https://ci.guix.gnu.org}.
5434 (use-modules (guix ci))
5436 (list (channel-with-substitutes-available
5437 %default-guix-channel
5438 "https://ci.guix.gnu.org"))
5441 Note that this does not mean that all the packages that you will
5442 install after running @command{guix pull} will have available
5443 substitutes. It only ensures that @command{guix pull} will not try to
5444 compile package definitions. This is particularly useful when using
5445 machines with limited resources.
5447 @node Creating a Channel
5448 @section Creating a Channel
5450 @cindex personal packages (channels)
5451 @cindex channels, for personal packages
5452 Let's say you have a bunch of custom package variants or personal packages
5453 that you think would make little sense to contribute to the Guix project, but
5454 would like to have these packages transparently available to you at the
5455 command line. You would first write modules containing those package
5456 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5457 then you and anyone else can use it as an additional channel to get packages
5460 @c What follows stems from discussions at
5461 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5462 @c earlier discussions on guix-devel@gnu.org.
5464 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5465 publish your personal channel to the world, we would like to share a few words
5470 Before publishing a channel, please consider contributing your package
5471 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5472 to free software of all sorts, and packages in Guix proper are readily
5473 available to all Guix users and benefit from the project's quality assurance
5477 When you maintain package definitions outside Guix, we, Guix developers,
5478 consider that @emph{the compatibility burden is on you}. Remember that
5479 package modules and package definitions are just Scheme code that uses various
5480 programming interfaces (APIs). We want to remain free to change these APIs to
5481 keep improving Guix, possibly in ways that break your channel. We never
5482 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5486 Corollary: if you're using an external channel and that channel breaks, please
5487 @emph{report the issue to the channel authors}, not to the Guix project.
5490 You've been warned! Having said this, we believe external channels are a
5491 practical way to exert your freedom to augment Guix' package collection and to
5492 share your improvements, which are basic tenets of
5493 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5494 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5497 To create a channel, create a Git repository containing your own package
5498 modules and make it available. The repository can contain anything, but a
5499 useful channel will contain Guile modules that export packages. Once you
5500 start using a channel, Guix will behave as if the root directory of that
5501 channel's Git repository has been added to the Guile load path (@pxref{Load
5502 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5503 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5504 module, then the module will be available under the name @code{(my-packages
5505 my-tools)}, and you will be able to use it like any other module
5506 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5508 As a channel author, consider bundling authentication material with your
5509 channel so that users can authenticate it. @xref{Channel
5510 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5514 @node Package Modules in a Sub-directory
5515 @section Package Modules in a Sub-directory
5517 @cindex subdirectory, channels
5518 As a channel author, you may want to keep your channel modules in a
5519 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5520 add a meta-data file @file{.guix-channel} that contains:
5528 @node Declaring Channel Dependencies
5529 @section Declaring Channel Dependencies
5531 @cindex dependencies, channels
5532 @cindex meta-data, channels
5533 Channel authors may decide to augment a package collection provided by other
5534 channels. They can declare their channel to be dependent on other channels in
5535 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5536 the channel repository.
5538 The meta-data file should contain a simple S-expression like this:
5545 (name some-collection)
5546 (url "https://example.org/first-collection.git")
5548 ;; The 'introduction' bit below is optional: you would
5549 ;; provide it for dependencies that can be authenticated.
5551 (channel-introduction
5553 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5554 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5556 (name some-other-collection)
5557 (url "https://example.org/second-collection.git")
5558 (branch "testing"))))
5561 In the above example this channel is declared to depend on two other channels,
5562 which will both be fetched automatically. The modules provided by the channel
5563 will be compiled in an environment where the modules of all these declared
5564 channels are available.
5566 For the sake of reliability and maintainability, you should avoid dependencies
5567 on channels that you don't control, and you should aim to keep the number of
5568 dependencies to a minimum.
5570 @node Specifying Channel Authorizations
5571 @section Specifying Channel Authorizations
5573 @cindex channel authorizations
5574 @anchor{channel-authorizations}
5575 As we saw above, Guix ensures the source code it pulls from channels
5576 comes from authorized developers. As a channel author, you need to
5577 specify the list of authorized developers in the
5578 @file{.guix-authorizations} file in the channel's Git repository. The
5579 authentication rule is simple: each commit must be signed by a key
5580 listed in the @file{.guix-authorizations} file of its parent
5581 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5582 (DAG). Each commit can have zero or more parents; ``regular'' commits
5583 have one parent and merge commits have two parent commits. Read
5584 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5585 for Computer Scientists}} for a great overview.} The
5586 @file{.guix-authorizations} file looks like this:
5589 ;; Example '.guix-authorizations' file.
5592 (version 0) ;current file format version
5594 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5596 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5598 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5602 Each fingerprint is followed by optional key/value pairs, as in the
5603 example above. Currently these key/value pairs are ignored.
5605 This authentication rule creates a chicken-and-egg issue: how do we
5606 authenticate the first commit? Related to that: how do we deal with
5607 channels whose repository history contains unsigned commits and lack
5608 @file{.guix-authorizations}? And how do we fork existing channels?
5610 @cindex channel introduction
5611 Channel introductions answer these questions by describing the first
5612 commit of a channel that should be authenticated. The first time a
5613 channel is fetched with @command{guix pull} or @command{guix
5614 time-machine}, the command looks up the introductory commit and verifies
5615 that it is signed by the specified OpenPGP key. From then on, it
5616 authenticates commits according to the rule above. Authentication fails
5617 if the target commit is neither a descendant nor an ancestor of the
5618 introductory commit.
5620 Additionally, your channel must provide all the OpenPGP keys that were
5621 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5622 files, which can be either binary or ``ASCII-armored''. By default,
5623 those @file{.key} files are searched for in the branch named
5624 @code{keyring} but you can specify a different branch name in
5625 @code{.guix-channel} like so:
5630 (keyring-reference "my-keyring-branch"))
5633 To summarize, as the author of a channel, there are three things you have
5634 to do to allow users to authenticate your code:
5638 Export the OpenPGP keys of past and present committers with @command{gpg
5639 --export} and store them in @file{.key} files, by default in a branch
5640 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5643 Introduce an initial @file{.guix-authorizations} in the channel's
5644 repository. Do that in a signed commit (@pxref{Commit Access}, for
5645 information on how to sign Git commits.)
5648 Advertise the channel introduction, for instance on your channel's web
5649 page. The channel introduction, as we saw above, is the commit/key
5650 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5651 the fingerprint of the OpenPGP used to sign it.
5654 Before pushing to your public Git repository, you can run @command{guix
5655 git-authenticate} to verify that you did sign all the commits you are
5656 about to push with an authorized key:
5659 guix git authenticate @var{commit} @var{signer}
5663 where @var{commit} and @var{signer} are your channel introduction.
5664 @xref{Invoking guix git authenticate}, for details.
5666 Publishing a signed channel requires discipline: any mistake, such as an
5667 unsigned commit or a commit signed by an unauthorized key, will prevent
5668 users from pulling from your channel---well, that's the whole point of
5669 authentication! Pay attention to merges in particular: merge commits
5670 are considered authentic if and only if they are signed by a key present
5671 in the @file{.guix-authorizations} file of @emph{both} branches.
5674 @section Primary URL
5676 @cindex primary URL, channels
5677 Channel authors can indicate the primary URL of their channel's Git
5678 repository in the @file{.guix-channel} file, like so:
5683 (url "https://example.org/guix.git"))
5686 This allows @command{guix pull} to determine whether it is pulling code
5687 from a mirror of the channel; when that is the case, it warns the user
5688 that the mirror might be stale and displays the primary URL@. That way,
5689 users cannot be tricked into fetching code from a stale mirror that does
5690 not receive security updates.
5692 This feature only makes sense for authenticated repositories, such as
5693 the official @code{guix} channel, for which @command{guix pull} ensures
5694 the code it fetches is authentic.
5696 @node Writing Channel News
5697 @section Writing Channel News
5699 @cindex news, for channels
5700 Channel authors may occasionally want to communicate to their users
5701 information about important changes in the channel. You'd send them all
5702 an email, but that's not convenient.
5704 Instead, channels can provide a @dfn{news file}; when the channel users
5705 run @command{guix pull}, that news file is automatically read and
5706 @command{guix pull --news} can display the announcements that correspond
5707 to the new commits that have been pulled, if any.
5709 To do that, channel authors must first declare the name of the news file
5710 in their @file{.guix-channel} file:
5715 (news-file "etc/news.txt"))
5718 The news file itself, @file{etc/news.txt} in this example, must look
5719 something like this:
5724 (entry (tag "the-bug-fix")
5725 (title (en "Fixed terrible bug")
5727 (body (en "@@emph@{Good news@}! It's fixed!")
5728 (eo "Certe ĝi pli bone funkcias nun!")))
5729 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5730 (title (en "Added a great package")
5731 (ca "Què vol dir guix?"))
5732 (body (en "Don't miss the @@code@{hello@} package!"))))
5735 While the news file is using the Scheme syntax, avoid naming it with a
5736 @file{.scm} extension or else it will get picked up when building the
5737 channel and yield an error since it is not a valid module.
5738 Alternatively, you can move the channel module to a subdirectory and
5739 store the news file in another directory.
5741 The file consists of a list of @dfn{news entries}. Each entry is
5742 associated with a commit or tag: it describes changes made in this
5743 commit, possibly in preceding commits as well. Users see entries only
5744 the first time they obtain the commit the entry refers to.
5746 The @code{title} field should be a one-line summary while @code{body}
5747 can be arbitrarily long, and both can contain Texinfo markup
5748 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5749 a list of language tag/message tuples, which allows @command{guix pull}
5750 to display news in the language that corresponds to the user's locale.
5752 If you want to translate news using a gettext-based workflow, you can
5753 extract translatable strings with @command{xgettext} (@pxref{xgettext
5754 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5755 you write news entries in English first, the command below creates a PO
5756 file containing the strings to translate:
5759 xgettext -o news.po -l scheme -ken etc/news.txt
5762 To sum up, yes, you could use your channel as a blog. But beware, this
5763 is @emph{not quite} what your users might expect.
5765 @c *********************************************************************
5767 @chapter Development
5769 @cindex software development
5770 If you are a software developer, Guix provides tools that you should find
5771 helpful---independently of the language you're developing in. This is what
5772 this chapter is about.
5774 The @command{guix shell} command provides a convenient way to set up
5775 one-off software environments, be it for development purposes or to run
5776 a command without installing it in your profile. The @command{guix
5777 pack} command allows you to create @dfn{application bundles} that can be
5778 easily distributed to users who do not run Guix.
5781 * Invoking guix shell:: Spawning one-off software environments.
5782 * Invoking guix environment:: Setting up development environments.
5783 * Invoking guix pack:: Creating software bundles.
5784 * The GCC toolchain:: Working with languages supported by GCC.
5785 * Invoking guix git authenticate:: Authenticating Git repositories.
5788 @node Invoking guix shell
5789 @section Invoking @command{guix shell}
5791 @cindex reproducible build environments
5792 @cindex development environments
5793 @cindex @command{guix environment}
5794 @cindex environment, package build environment
5795 The purpose of @command{guix shell} is to make it easy to create one-off
5796 software environments, without changing one's profile. It is typically
5797 used to create development environments; it is also a convenient way to
5798 run applications without ``polluting'' your profile.
5801 The @command{guix shell} command was recently introduced to supersede
5802 @command{guix environment} (@pxref{Invoking guix environment}). If you
5803 are familiar with @command{guix environment}, you will notice that it is
5804 similar but also---we hope!---more convenient.
5807 The general syntax is:
5810 guix shell [@var{options}] [@var{package}@dots{}]
5813 The following example creates an environment containing Python and NumPy,
5814 building or downloading any missing package, and runs the
5815 @command{python3} command in that environment:
5818 guix shell python python-numpy -- python3
5821 Development environments can be created as in the example below, which
5822 spawns an interactive shell containing all the dependencies and
5823 environment variables needed to work on Inkscape:
5826 guix shell --development inkscape
5829 Exiting the shell places the user back in the original environment
5830 before @command{guix shell} was invoked. The next garbage collection
5831 (@pxref{Invoking guix gc}) may clean up packages that were installed in
5832 the environment and that are no longer used outside of it.
5834 As an added convenience, @command{guix shell} will try to do what you
5835 mean when it is invoked interactively without any other arguments
5842 If it finds a @file{manifest.scm} in the current working directory or
5843 any of its parents, it uses this manifest as though it was given via @code{--manifest}.
5844 Likewise, if it finds a @file{guix.scm} in the same directories, it uses
5845 it to build a development profile as though both @code{--development}
5846 and @code{--file} were present.
5847 In either case, the file will only be loaded if the directory it
5848 resides in is listed in
5849 @file{~/.config/guix/shell-authorized-directories}.
5850 This provides an easy way to define, share, and enter development
5853 By default, the shell session or command runs in an @emph{augmented}
5854 environment, where the new packages are added to search path environment
5855 variables such as @code{PATH}. You can, instead, choose to create an
5856 @emph{isolated} environment containing nothing but the packages you
5857 asked for. Passing the @option{--pure} option clears environment
5858 variable definitions found in the parent environment@footnote{Be sure to
5859 use the @option{--check} option the first time you use @command{guix
5860 shell} interactively to make sure the shell does not undo the effect of
5861 @option{--pure}.}; passing @option{--container} goes one step further by
5862 spawning a @dfn{container} isolated from the rest of the system:
5865 guix shell --container emacs gcc-toolchain
5868 The command above spawns an interactive shell in a container where
5869 nothing but @code{emacs}, @code{gcc-toolchain}, and their dependencies
5870 is available. The container lacks network access and shares no files
5871 other than the current working directory with the surrounding
5872 environment. This is useful to prevent access to system-wide resources
5873 such as @file{/usr/bin} on foreign distros.
5875 This @option{--container} option can also prove useful if you wish to
5876 run a security-sensitive application, such as a web browser, in an
5877 isolated environment. For example, the command below launches
5878 Ungoogled-Chromium in an isolated environment, this time sharing network
5879 access with the host and preserving its @code{DISPLAY} environment
5880 variable, but without even sharing the current directory:
5883 guix shell --container --network --no-cwd ungoogled-chromium \
5884 --preserve='^DISPLAY$' -- chromium
5887 @vindex GUIX_ENVIRONMENT
5888 @command{guix shell} defines the @env{GUIX_ENVIRONMENT}
5889 variable in the shell it spawns; its value is the file name of the
5890 profile of this environment. This allows users to, say, define a
5891 specific prompt for development environments in their @file{.bashrc}
5892 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5895 if [ -n "$GUIX_ENVIRONMENT" ]
5897 export PS1="\u@@\h \w [dev]\$ "
5902 ...@: or to browse the profile:
5905 $ ls "$GUIX_ENVIRONMENT/bin"
5908 The available options are summarized below.
5912 Set up the environment and check whether the shell would clobber
5913 environment variables. It's a good idea to use this option the first
5914 time you run @command{guix shell} for an interactive session to make
5915 sure your setup is correct.
5917 For example, if the shell modifies the @env{PATH} environment variable,
5918 report it since you would get a different environment than what you
5921 Such problems usually indicate that the shell startup files are
5922 unexpectedly modifying those environment variables. For example, if you
5923 are using Bash, make sure that environment variables are set or modified
5924 in @file{~/.bash_profile} and @emph{not} in @file{~/.bashrc}---the
5925 former is sourced only by log-in shells. @xref{Bash Startup Files,,,
5926 bash, The GNU Bash Reference Manual}, for details on Bash start-up
5929 @anchor{shell-development-option}
5932 Cause @command{guix shell} to include in the environment the
5933 dependencies of the following package rather than the package itself.
5934 This can be combined with other packages. For instance, the command
5935 below starts an interactive shell containing the build-time dependencies
5936 of GNU@tie{}Guile, plus Autoconf, Automake, and Libtool:
5939 guix shell -D guile autoconf automake libtool
5942 @item --expression=@var{expr}
5943 @itemx -e @var{expr}
5944 Create an environment for the package or list of packages that
5945 @var{expr} evaluates to.
5947 For example, running:
5950 guix shell -D -e '(@@ (gnu packages maths) petsc-openmpi)'
5953 starts a shell with the environment for this specific variant of the
5959 guix shell -e '(@@ (gnu) %base-packages)'
5962 starts a shell with all the base system packages available.
5964 The above commands only use the default output of the given packages.
5965 To select other outputs, two element tuples can be specified:
5968 guix shell -e '(list (@@ (gnu packages bash) bash) "include")'
5971 @xref{package-development-manifest,
5972 @code{package->development-manifest}}, for information on how to write a
5973 manifest for the development environment of a package.
5975 @item --file=@var{file}
5976 @itemx -f @var{file}
5977 Create an environment containing the package or list of packages that
5978 the code within @var{file} evaluates to.
5980 As an example, @var{file} might contain a definition like this
5981 (@pxref{Defining Packages}):
5984 @verbatiminclude environment-gdb.scm
5987 With the file above, you can enter a development environment for GDB by
5991 guix shell -D -f gdb-devel.scm
5994 @anchor{shell-manifest}
5995 @item --manifest=@var{file}
5996 @itemx -m @var{file}
5997 Create an environment for the packages contained in the manifest object
5998 returned by the Scheme code in @var{file}. This option can be repeated
5999 several times, in which case the manifests are concatenated.
6001 This is similar to the same-named option in @command{guix package}
6002 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
6005 @xref{Writing Manifests}, for information on how to write a manifest.
6006 See @option{--export-manifest} below on how to obtain a first manifest.
6008 @cindex manifest, exporting
6009 @anchor{shell-export-manifest}
6010 @item --export-manifest
6011 Write to standard output a manifest suitable for @option{--manifest}
6012 corresponding to given command-line options.
6014 This is a way to ``convert'' command-line arguments into a manifest.
6015 For example, imagine you are tired of typing long lines and would like
6016 to get a manifest equivalent to this command line:
6019 guix shell -D guile git emacs emacs-geiser emacs-geiser-guile
6022 Just add @option{--export-manifest} to the command line above:
6025 guix shell --export-manifest \
6026 -D guile git emacs emacs-geiser emacs-geiser-guile
6030 ... and you get a manifest along these lines:
6033 (concatenate-manifests
6034 (list (specifications->manifest
6038 "emacs-geiser-guile"))
6039 (package->development-manifest
6040 (specification->package "guile"))))
6043 You can store it into a file, say @file{manifest.scm}, and from there
6044 pass it to @command{guix shell} or indeed pretty much any @command{guix}
6048 guix shell -m manifest.scm
6051 Voilà, you've converted a long command line into a manifest! That
6052 conversion process honors package transformation options (@pxref{Package
6053 Transformation Options}) so it should be lossless.
6055 @item --profile=@var{profile}
6056 @itemx -p @var{profile}
6057 Create an environment containing the packages installed in @var{profile}.
6058 Use @command{guix package} (@pxref{Invoking guix package}) to create
6059 and manage profiles.
6062 Unset existing environment variables when building the new environment, except
6063 those specified with @option{--preserve} (see below). This has the effect of
6064 creating an environment in which search paths only contain package inputs.
6066 @item --preserve=@var{regexp}
6067 @itemx -E @var{regexp}
6068 When used alongside @option{--pure}, preserve the environment variables
6069 matching @var{regexp}---in other words, put them on a ``white list'' of
6070 environment variables that must be preserved. This option can be repeated
6074 guix shell --pure --preserve=^SLURM openmpi @dots{} \
6078 This example runs @command{mpirun} in a context where the only environment
6079 variables defined are @env{PATH}, environment variables whose name starts
6080 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
6083 @item --search-paths
6084 Display the environment variable definitions that make up the
6087 @item --system=@var{system}
6088 @itemx -s @var{system}
6089 Attempt to build for @var{system}---e.g., @code{i686-linux}.
6094 Run @var{command} within an isolated container. The current working
6095 directory outside the container is mapped inside the container.
6096 Additionally, unless overridden with @option{--user}, a dummy home
6097 directory is created that matches the current user's home directory, and
6098 @file{/etc/passwd} is configured accordingly.
6100 The spawned process runs as the current user outside the container. Inside
6101 the container, it has the same UID and GID as the current user, unless
6102 @option{--user} is passed (see below).
6106 For containers, share the network namespace with the host system.
6107 Containers created without this flag only have access to the loopback
6110 @item --link-profile
6112 For containers, link the environment profile to @file{~/.guix-profile}
6113 within the container and set @code{GUIX_ENVIRONMENT} to that.
6114 This is equivalent to making @file{~/.guix-profile} a symlink to the
6115 actual profile within the container.
6116 Linking will fail and abort the environment if the directory already
6117 exists, which will certainly be the case if @command{guix shell}
6118 was invoked in the user's home directory.
6120 Certain packages are configured to look in @file{~/.guix-profile} for
6121 configuration files and data;@footnote{For example, the
6122 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
6123 for additional fonts.} @option{--link-profile} allows these programs to
6124 behave as expected within the environment.
6126 @item --user=@var{user}
6127 @itemx -u @var{user}
6128 For containers, use the username @var{user} in place of the current
6129 user. The generated @file{/etc/passwd} entry within the container will
6130 contain the name @var{user}, the home directory will be
6131 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
6132 the UID and GID inside the container are 1000. @var{user}
6133 need not exist on the system.
6135 Additionally, any shared or exposed path (see @option{--share} and
6136 @option{--expose} respectively) whose target is within the current user's
6137 home directory will be remapped relative to @file{/home/USER}; this
6138 includes the automatic mapping of the current working directory.
6141 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
6143 guix shell --container --user=foo \
6144 --expose=$HOME/test \
6145 --expose=/tmp/target=$HOME/target
6148 While this will limit the leaking of user identity through home paths
6149 and each of the user fields, this is only one useful component of a
6150 broader privacy/anonymity solution---not one in and of itself.
6153 For containers, the default behavior is to share the current working
6154 directory with the isolated container and immediately change to that
6155 directory within the container. If this is undesirable,
6156 @option{--no-cwd} will cause the current working directory to @emph{not}
6157 be automatically shared and will change to the user's home directory
6158 within the container instead. See also @option{--user}.
6160 @item --expose=@var{source}[=@var{target}]
6161 @itemx --share=@var{source}[=@var{target}]
6162 For containers, @option{--expose} (resp. @option{--share}) exposes the
6163 file system @var{source} from the host system as the read-only
6164 (resp. writable) file system @var{target} within the container. If
6165 @var{target} is not specified, @var{source} is used as the target mount
6166 point in the container.
6168 The example below spawns a Guile REPL in a container in which the user's
6169 home directory is accessible read-only via the @file{/exchange}
6173 guix shell --container --expose=$HOME=/exchange guile -- guile
6176 @item --rebuild-cache
6177 @cindex caching, of profiles
6178 @cindex caching, in @command{guix shell}
6179 In most cases, @command{guix shell} caches the environment so that
6180 subsequent uses are instantaneous. Least-recently used cache entries
6181 are periodically removed. The cache is also invalidated, when using
6182 @option{--file} or @option{--manifest}, anytime the corresponding file
6185 The @option{--rebuild-cache} forces the cached environment to be
6186 refreshed. This is useful when using @option{--file} or
6187 @option{--manifest} and the @command{guix.scm} or @command{manifest.scm}
6188 file has external dependencies, or if its behavior depends, say, on
6189 environment variables.
6191 @item --root=@var{file}
6192 @itemx -r @var{file}
6193 @cindex persistent environment
6194 @cindex garbage collector root, for environments
6195 Make @var{file} a symlink to the profile for this environment, and
6196 register it as a garbage collector root.
6198 This is useful if you want to protect your environment from garbage
6199 collection, to make it ``persistent''.
6201 When this option is omitted, @command{guix shell} caches profiles so
6202 that subsequent uses of the same environment are instantaneous---this is
6203 comparable to using @option{--root} except that @command{guix shell}
6204 takes care of periodically removing the least-recently used garbage
6207 In some cases, @command{guix shell} does not cache profiles---e.g., if
6208 transformation options such as @option{--with-latest} are used. In
6209 those cases, the environment is protected from garbage collection only
6210 for the duration of the @command{guix shell} session. This means that
6211 next time you recreate the same environment, you could have to rebuild
6212 or re-download packages.
6214 @xref{Invoking guix gc}, for more on GC roots.
6217 @command{guix shell} also supports all of the common build options that
6218 @command{guix build} supports (@pxref{Common Build Options}) as well as
6219 package transformation options (@pxref{Package Transformation Options}).
6221 @node Invoking guix environment
6222 @section Invoking @command{guix environment}
6224 The purpose of @command{guix environment} is to assist in creating
6225 development environments.
6227 @quotation Deprecation warning
6228 The @command{guix environment} command is deprecated in favor of
6229 @command{guix shell}, which performs similar functions but is more
6230 convenient to use. @xref{Invoking guix shell}.
6232 Being deprecated, @command{guix environment} is slated for eventual
6233 removal, but the Guix project is committed to keeping it until May 1st,
6234 2023. Please get in touch with us at @email{guix-devel@@gnu.org} if you
6235 would like to discuss it.
6238 The general syntax is:
6241 guix environment @var{options} @var{package}@dots{}
6244 The following example spawns a new shell set up for the development of
6248 guix environment guile
6251 If the needed dependencies are not built yet, @command{guix environment}
6252 automatically builds them. The environment of the new shell is an
6253 augmented version of the environment that @command{guix environment} was
6254 run in. It contains the necessary search paths for building the given
6255 package added to the existing environment variables. To create
6256 a ``pure'' environment, in which the original environment variables have
6257 been unset, use the @option{--pure} option@footnote{Users sometimes
6258 wrongfully augment environment variables such as @env{PATH} in their
6259 @file{~/.bashrc} file. As a consequence, when @command{guix
6260 environment} launches it, Bash may read @file{~/.bashrc}, thereby
6261 introducing ``impurities'' in these environment variables. It is an
6262 error to define such environment variables in @file{.bashrc}; instead,
6263 they should be defined in @file{.bash_profile}, which is sourced only by
6264 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
6265 Manual}, for details on Bash start-up files.}.
6267 Exiting from a Guix environment is the same as exiting from the shell,
6268 and will place the user back in the old environment before @command{guix
6269 environment} was invoked. The next garbage collection (@pxref{Invoking
6270 guix gc}) will clean up packages that were installed from within the
6271 environment and are no longer used outside of it.
6273 @vindex GUIX_ENVIRONMENT
6274 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
6275 variable in the shell it spawns; its value is the file name of the
6276 profile of this environment. This allows users to, say, define a
6277 specific prompt for development environments in their @file{.bashrc}
6278 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
6281 if [ -n "$GUIX_ENVIRONMENT" ]
6283 export PS1="\u@@\h \w [dev]\$ "
6288 ...@: or to browse the profile:
6291 $ ls "$GUIX_ENVIRONMENT/bin"
6294 Additionally, more than one package may be specified, in which case the
6295 union of the inputs for the given packages are used. For example, the
6296 command below spawns a shell where all of the dependencies of both Guile
6297 and Emacs are available:
6300 guix environment guile emacs
6303 Sometimes an interactive shell session is not desired. An arbitrary
6304 command may be invoked by placing the @code{--} token to separate the
6305 command from the rest of the arguments:
6308 guix environment guile -- make -j4
6311 In other situations, it is more convenient to specify the list of
6312 packages needed in the environment. For example, the following command
6313 runs @command{python} from an environment containing Python@tie{}3 and
6317 guix environment --ad-hoc python-numpy python -- python3
6320 Furthermore, one might want the dependencies of a package and also some
6321 additional packages that are not build-time or runtime dependencies, but
6322 are useful when developing nonetheless. Because of this, the
6323 @option{--ad-hoc} flag is positional. Packages appearing before
6324 @option{--ad-hoc} are interpreted as packages whose dependencies will be
6325 added to the environment. Packages appearing after are interpreted as
6326 packages that will be added to the environment directly. For example,
6327 the following command creates a Guix development environment that
6328 additionally includes Git and strace:
6331 guix environment --pure guix --ad-hoc git strace
6335 Sometimes it is desirable to isolate the environment as much as
6336 possible, for maximal purity and reproducibility. In particular, when
6337 using Guix on a host distro that is not Guix System, it is desirable to
6338 prevent access to @file{/usr/bin} and other system-wide resources from
6339 the development environment. For example, the following command spawns
6340 a Guile REPL in a ``container'' where only the store and the current
6341 working directory are mounted:
6344 guix environment --ad-hoc --container guile -- guile
6348 The @option{--container} option requires Linux-libre 3.19 or newer.
6351 @cindex certificates
6352 Another typical use case for containers is to run security-sensitive
6353 applications such as a web browser. To run Eolie, we must expose and
6354 share some files and directories; we include @code{nss-certs} and expose
6355 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
6356 @env{DISPLAY} environment variable since containerized graphical
6357 applications won't display without it.
6360 guix environment --preserve='^DISPLAY$' --container --network \
6361 --expose=/etc/machine-id \
6362 --expose=/etc/ssl/certs/ \
6363 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
6364 --ad-hoc eolie nss-certs dbus -- eolie
6367 The available options are summarized below.
6371 Set up the environment and check whether the shell would clobber
6372 environment variables. @xref{Invoking guix shell, @option{--check}},
6375 @item --root=@var{file}
6376 @itemx -r @var{file}
6377 @cindex persistent environment
6378 @cindex garbage collector root, for environments
6379 Make @var{file} a symlink to the profile for this environment, and
6380 register it as a garbage collector root.
6382 This is useful if you want to protect your environment from garbage
6383 collection, to make it ``persistent''.
6385 When this option is omitted, the environment is protected from garbage
6386 collection only for the duration of the @command{guix environment}
6387 session. This means that next time you recreate the same environment,
6388 you could have to rebuild or re-download packages. @xref{Invoking guix
6389 gc}, for more on GC roots.
6391 @item --expression=@var{expr}
6392 @itemx -e @var{expr}
6393 Create an environment for the package or list of packages that
6394 @var{expr} evaluates to.
6396 For example, running:
6399 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
6402 starts a shell with the environment for this specific variant of the
6408 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
6411 starts a shell with all the base system packages available.
6413 The above commands only use the default output of the given packages.
6414 To select other outputs, two element tuples can be specified:
6417 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
6420 @item --load=@var{file}
6421 @itemx -l @var{file}
6422 Create an environment for the package or list of packages that the code
6423 within @var{file} evaluates to.
6425 As an example, @var{file} might contain a definition like this
6426 (@pxref{Defining Packages}):
6429 @verbatiminclude environment-gdb.scm
6432 @item --manifest=@var{file}
6433 @itemx -m @var{file}
6434 Create an environment for the packages contained in the manifest object
6435 returned by the Scheme code in @var{file}. This option can be repeated
6436 several times, in which case the manifests are concatenated.
6438 This is similar to the same-named option in @command{guix package}
6439 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
6442 @xref{shell-export-manifest, @command{guix shell --export-manifest}},
6443 for information on how to ``convert'' command-line options into a
6447 Include all specified packages in the resulting environment, as if an
6448 @i{ad hoc} package were defined with them as inputs. This option is
6449 useful for quickly creating an environment without having to write a
6450 package expression to contain the desired inputs.
6452 For instance, the command:
6455 guix environment --ad-hoc guile guile-sdl -- guile
6458 runs @command{guile} in an environment where Guile and Guile-SDL are
6461 Note that this example implicitly asks for the default output of
6462 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
6463 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
6464 of @code{glib} (@pxref{Packages with Multiple Outputs}).
6466 This option may be composed with the default behavior of @command{guix
6467 environment}. Packages appearing before @option{--ad-hoc} are
6468 interpreted as packages whose dependencies will be added to the
6469 environment, the default behavior. Packages appearing after are
6470 interpreted as packages that will be added to the environment directly.
6472 @item --profile=@var{profile}
6473 @itemx -p @var{profile}
6474 Create an environment containing the packages installed in @var{profile}.
6475 Use @command{guix package} (@pxref{Invoking guix package}) to create
6476 and manage profiles.
6479 Unset existing environment variables when building the new environment, except
6480 those specified with @option{--preserve} (see below). This has the effect of
6481 creating an environment in which search paths only contain package inputs.
6483 @item --preserve=@var{regexp}
6484 @itemx -E @var{regexp}
6485 When used alongside @option{--pure}, preserve the environment variables
6486 matching @var{regexp}---in other words, put them on a ``white list'' of
6487 environment variables that must be preserved. This option can be repeated
6491 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
6495 This example runs @command{mpirun} in a context where the only environment
6496 variables defined are @env{PATH}, environment variables whose name starts
6497 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
6500 @item --search-paths
6501 Display the environment variable definitions that make up the
6504 @item --system=@var{system}
6505 @itemx -s @var{system}
6506 Attempt to build for @var{system}---e.g., @code{i686-linux}.
6511 Run @var{command} within an isolated container. The current working
6512 directory outside the container is mapped inside the container.
6513 Additionally, unless overridden with @option{--user}, a dummy home
6514 directory is created that matches the current user's home directory, and
6515 @file{/etc/passwd} is configured accordingly.
6517 The spawned process runs as the current user outside the container. Inside
6518 the container, it has the same UID and GID as the current user, unless
6519 @option{--user} is passed (see below).
6523 For containers, share the network namespace with the host system.
6524 Containers created without this flag only have access to the loopback
6527 @item --link-profile
6529 For containers, link the environment profile to @file{~/.guix-profile}
6530 within the container and set @code{GUIX_ENVIRONMENT} to that.
6531 This is equivalent to making @file{~/.guix-profile} a symlink to the
6532 actual profile within the container.
6533 Linking will fail and abort the environment if the directory already
6534 exists, which will certainly be the case if @command{guix environment}
6535 was invoked in the user's home directory.
6537 Certain packages are configured to look in @file{~/.guix-profile} for
6538 configuration files and data;@footnote{For example, the
6539 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
6540 for additional fonts.} @option{--link-profile} allows these programs to
6541 behave as expected within the environment.
6543 @item --user=@var{user}
6544 @itemx -u @var{user}
6545 For containers, use the username @var{user} in place of the current
6546 user. The generated @file{/etc/passwd} entry within the container will
6547 contain the name @var{user}, the home directory will be
6548 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
6549 the UID and GID inside the container are 1000. @var{user}
6550 need not exist on the system.
6552 Additionally, any shared or exposed path (see @option{--share} and
6553 @option{--expose} respectively) whose target is within the current user's
6554 home directory will be remapped relative to @file{/home/USER}; this
6555 includes the automatic mapping of the current working directory.
6558 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
6560 guix environment --container --user=foo \
6561 --expose=$HOME/test \
6562 --expose=/tmp/target=$HOME/target
6565 While this will limit the leaking of user identity through home paths
6566 and each of the user fields, this is only one useful component of a
6567 broader privacy/anonymity solution---not one in and of itself.
6570 For containers, the default behavior is to share the current working
6571 directory with the isolated container and immediately change to that
6572 directory within the container. If this is undesirable,
6573 @option{--no-cwd} will cause the current working directory to @emph{not}
6574 be automatically shared and will change to the user's home directory
6575 within the container instead. See also @option{--user}.
6577 @item --expose=@var{source}[=@var{target}]
6578 @itemx --share=@var{source}[=@var{target}]
6579 For containers, @option{--expose} (resp. @option{--share}) exposes the
6580 file system @var{source} from the host system as the read-only
6581 (resp. writable) file system @var{target} within the container. If
6582 @var{target} is not specified, @var{source} is used as the target mount
6583 point in the container.
6585 The example below spawns a Guile REPL in a container in which the user's
6586 home directory is accessible read-only via the @file{/exchange}
6590 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
6595 @command{guix environment}
6596 also supports all of the common build options that @command{guix
6597 build} supports (@pxref{Common Build Options}) as well as package
6598 transformation options (@pxref{Package Transformation Options}).
6600 @node Invoking guix pack
6601 @section Invoking @command{guix pack}
6603 Occasionally you want to pass software to people who are not (yet!)
6604 lucky enough to be using Guix. You'd tell them to run @command{guix
6605 package -i @var{something}}, but that's not possible in this case. This
6606 is where @command{guix pack} comes in.
6609 If you are looking for ways to exchange binaries among machines that
6610 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
6611 publish}, and @ref{Invoking guix archive}.
6616 @cindex application bundle
6617 @cindex software bundle
6618 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
6619 @dfn{software bundle}: it creates a tarball or some other archive
6620 containing the binaries of the software you're interested in, and all
6621 its dependencies. The resulting archive can be used on any machine that
6622 does not have Guix, and people can run the exact same binaries as those
6623 you have with Guix. The pack itself is created in a bit-reproducible
6624 fashion, so anyone can verify that it really contains the build results
6625 that you pretend to be shipping.
6627 For example, to create a bundle containing Guile, Emacs, Geiser, and all
6628 their dependencies, you can run:
6631 $ guix pack guile emacs emacs-geiser
6633 /gnu/store/@dots{}-pack.tar.gz
6636 The result here is a tarball containing a @file{/gnu/store} directory
6637 with all the relevant packages. The resulting tarball contains a
6638 @dfn{profile} with the three packages of interest; the profile is the
6639 same as would be created by @command{guix package -i}. It is this
6640 mechanism that is used to create Guix's own standalone binary tarball
6641 (@pxref{Binary Installation}).
6643 Users of this pack would have to run
6644 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
6645 find inconvenient. To work around it, you can create, say, a
6646 @file{/opt/gnu/bin} symlink to the profile:
6649 guix pack -S /opt/gnu/bin=bin guile emacs emacs-geiser
6653 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
6655 @cindex relocatable binaries, with @command{guix pack}
6656 What if the recipient of your pack does not have root privileges on
6657 their machine, and thus cannot unpack it in the root file system? In
6658 that case, you will want to use the @option{--relocatable} option (see
6659 below). This option produces @dfn{relocatable binaries}, meaning they
6660 they can be placed anywhere in the file system hierarchy: in the example
6661 above, users can unpack your tarball in their home directory and
6662 directly run @file{./opt/gnu/bin/guile}.
6664 @cindex Docker, build an image with guix pack
6665 Alternatively, you can produce a pack in the Docker image format using
6666 the following command:
6669 guix pack -f docker -S /bin=bin guile guile-readline
6673 The result is a tarball that can be passed to the @command{docker load}
6674 command, followed by @code{docker run}:
6677 docker load < @var{file}
6678 docker run -ti guile-guile-readline /bin/guile
6682 where @var{file} is the image returned by @var{guix pack}, and
6683 @code{guile-guile-readline} is its ``image tag''. See the
6684 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
6685 documentation} for more information.
6687 @cindex Singularity, build an image with guix pack
6688 @cindex SquashFS, build an image with guix pack
6689 Yet another option is to produce a SquashFS image with the following
6693 guix pack -f squashfs bash guile emacs emacs-geiser
6697 The result is a SquashFS file system image that can either be mounted or
6698 directly be used as a file system container image with the
6699 @uref{https://www.sylabs.io/docs/, Singularity container execution
6700 environment}, using commands like @command{singularity shell} or
6701 @command{singularity exec}.
6703 Several command-line options allow you to customize your pack:
6706 @item --format=@var{format}
6707 @itemx -f @var{format}
6708 Produce a pack in the given @var{format}.
6710 The available formats are:
6714 This is the default format. It produces a tarball containing all the
6715 specified binaries and symlinks.
6718 This produces a tarball that follows the
6719 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
6720 Docker Image Specification}. The ``repository name'' as it appears in
6721 the output of the @command{docker images} command is computed from
6722 package names passed on the command line or in the manifest file.
6725 This produces a SquashFS image containing all the specified binaries and
6726 symlinks, as well as empty mount points for virtual file systems like
6730 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
6731 For that reason, @command{guix pack -f squashfs} always implies @code{-S
6732 /bin=bin}. Thus, your @command{guix pack} invocation must always start
6733 with something like:
6736 guix pack -f squashfs bash @dots{}
6739 If you forget the @code{bash} (or similar) package, @command{singularity
6740 run} and @command{singularity exec} will fail with an unhelpful ``no
6741 such file or directory'' message.
6745 This produces a Debian archive (a package with the @samp{.deb} file
6746 extension) containing all the specified binaries and symbolic links,
6747 that can be installed on top of any dpkg-based GNU(/Linux) distribution.
6748 Advanced options can be revealed via the @option{--help-deb-format}
6749 option. They allow embedding control files for more fine-grained
6750 control, such as activating specific triggers or providing a maintainer
6751 configure script to run arbitrary setup code upon installation.
6754 guix pack -f deb -C xz -S /usr/bin/hello=bin/hello hello
6758 Because archives produced with @command{guix pack} contain a collection
6759 of store items and because each @command{dpkg} package must not have
6760 conflicting files, in practice that means you likely won't be able to
6761 install more than one such archive on a given system.
6765 @command{dpkg} will assume ownership of any files contained in the pack
6766 that it does @emph{not} know about. It is unwise to install
6767 Guix-produced @samp{.deb} files on a system where @file{/gnu/store} is
6768 shared by other software, such as a Guix installation or other, non-deb
6774 @cindex relocatable binaries
6777 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
6778 anywhere in the file system hierarchy and run from there.
6780 When this option is passed once, the resulting binaries require support for
6781 @dfn{user namespaces} in the kernel Linux; when passed
6782 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
6783 PRoot support, can be thought of as the abbreviation of ``Really
6784 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
6785 other techniques if user namespaces are unavailable, and essentially
6786 work anywhere---see below for the implications.
6788 For example, if you create a pack containing Bash with:
6791 guix pack -RR -S /mybin=bin bash
6795 ...@: you can copy that pack to a machine that lacks Guix, and from your
6796 home directory as a normal user, run:
6804 In that shell, if you type @code{ls /gnu/store}, you'll notice that
6805 @file{/gnu/store} shows up and contains all the dependencies of
6806 @code{bash}, even though the machine actually lacks @file{/gnu/store}
6807 altogether! That is probably the simplest way to deploy Guix-built
6808 software on a non-Guix machine.
6811 By default, relocatable binaries rely on the @dfn{user namespace} feature of
6812 the kernel Linux, which allows unprivileged users to mount or change root.
6813 Old versions of Linux did not support it, and some GNU/Linux distributions
6816 To produce relocatable binaries that work even in the absence of user
6817 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
6818 case, binaries will try user namespace support and fall back to another
6819 @dfn{execution engine} if user namespaces are not supported. The
6820 following execution engines are supported:
6824 Try user namespaces and fall back to PRoot if user namespaces are not
6825 supported (see below).
6828 Try user namespaces and fall back to Fakechroot if user namespaces are
6829 not supported (see below).
6832 Run the program through user namespaces and abort if they are not
6836 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
6837 provides the necessary
6838 support for file system virtualization. It achieves that by using the
6839 @code{ptrace} system call on the running program. This approach has the
6840 advantage to work without requiring special kernel support, but it incurs
6841 run-time overhead every time a system call is made.
6844 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
6845 Fakechroot} virtualizes file system accesses by intercepting calls to C
6846 library functions such as @code{open}, @code{stat}, @code{exec}, and so
6847 on. Unlike PRoot, it incurs very little overhead. However, it does not
6848 always work: for example, some file system accesses made from within the
6849 C library are not intercepted, and file system accesses made @i{via}
6850 direct syscalls are not intercepted either, leading to erratic behavior.
6853 @vindex GUIX_EXECUTION_ENGINE
6854 When running a wrapped program, you can explicitly request one of the
6855 execution engines listed above by setting the
6856 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
6859 @cindex entry point, for Docker images
6860 @item --entry-point=@var{command}
6861 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
6862 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
6863 support it. @var{command} must be relative to the profile contained in the
6866 The entry point specifies the command that tools like @code{docker run} or
6867 @code{singularity run} automatically start by default. For example, you can
6871 guix pack -f docker --entry-point=bin/guile guile
6874 The resulting pack can easily be loaded and @code{docker run} with no extra
6875 arguments will spawn @code{bin/guile}:
6878 docker load -i pack.tar.gz
6879 docker run @var{image-id}
6882 @item --expression=@var{expr}
6883 @itemx -e @var{expr}
6884 Consider the package @var{expr} evaluates to.
6886 This has the same purpose as the same-named option in @command{guix
6887 build} (@pxref{Additional Build Options, @option{--expression} in
6888 @command{guix build}}).
6890 @anchor{pack-manifest}
6891 @item --manifest=@var{file}
6892 @itemx -m @var{file}
6893 Use the packages contained in the manifest object returned by the Scheme
6894 code in @var{file}. This option can be repeated several times, in which
6895 case the manifests are concatenated.
6897 This has a similar purpose as the same-named option in @command{guix
6898 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6899 same manifest files. It allows you to define a collection of packages
6900 once and use it both for creating profiles and for creating archives
6901 for use on machines that do not have Guix installed. Note that you can
6902 specify @emph{either} a manifest file @emph{or} a list of packages,
6905 @xref{Writing Manifests}, for information on how to write a manifest.
6906 @xref{shell-export-manifest, @command{guix shell --export-manifest}},
6907 for information on how to ``convert'' command-line options into a
6910 @item --system=@var{system}
6911 @itemx -s @var{system}
6912 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6913 the system type of the build host.
6915 @item --target=@var{triplet}
6916 @cindex cross-compilation
6917 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6918 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6919 configuration triplets,, autoconf, Autoconf}).
6921 @item --compression=@var{tool}
6922 @itemx -C @var{tool}
6923 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6924 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6927 @item --symlink=@var{spec}
6928 @itemx -S @var{spec}
6929 Add the symlinks specified by @var{spec} to the pack. This option can
6930 appear several times.
6932 @var{spec} has the form @code{@var{source}=@var{target}}, where
6933 @var{source} is the symlink that will be created and @var{target} is the
6936 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6937 symlink pointing to the @file{bin} sub-directory of the profile.
6939 @item --save-provenance
6940 Save provenance information for the packages passed on the command line.
6941 Provenance information includes the URL and commit of the channels in use
6944 Provenance information is saved in the
6945 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6946 usual package metadata---the name and version of each package, their
6947 propagated inputs, and so on. It is useful information to the recipient of
6948 the pack, who then knows how the pack was (supposedly) obtained.
6950 This option is not enabled by default because, like timestamps, provenance
6951 information contributes nothing to the build process. In other words, there
6952 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6953 Recording such ``silent'' metadata in the output thus potentially breaks the
6954 source-to-binary bitwise reproducibility property.
6956 @item --root=@var{file}
6957 @itemx -r @var{file}
6958 @cindex garbage collector root, for packs
6959 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6962 @item --localstatedir
6963 @itemx --profile-name=@var{name}
6964 Include the ``local state directory'', @file{/var/guix}, in the resulting
6965 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6966 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6967 @file{~root/.guix-profile}.
6969 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6970 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6971 the pack means that the store is ``complete'' and manageable by Guix;
6972 not providing it pack means that the store is ``dead'': items cannot be
6973 added to it or removed from it after extraction of the pack.
6975 One use case for this is the Guix self-contained binary tarball
6976 (@pxref{Binary Installation}).
6980 Print the name of the derivation that builds the pack.
6983 Use the bootstrap binaries to build the pack. This option is only
6984 useful to Guix developers.
6987 In addition, @command{guix pack} supports all the common build options
6988 (@pxref{Common Build Options}) and all the package transformation
6989 options (@pxref{Package Transformation Options}).
6992 @node The GCC toolchain
6993 @section The GCC toolchain
6997 @cindex linker wrapper
6998 @cindex toolchain, for C development
6999 @cindex toolchain, for Fortran development
7001 If you need a complete toolchain for compiling and linking C or C++
7002 source code, use the @code{gcc-toolchain} package. This package
7003 provides a complete GCC toolchain for C/C++ development, including GCC
7004 itself, the GNU C Library (headers and binaries, plus debugging symbols
7005 in the @code{debug} output), Binutils, and a linker wrapper.
7007 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
7008 passed to the linker, add corresponding @code{-rpath} arguments, and
7009 invoke the actual linker with this new set of arguments. You can instruct the
7010 wrapper to refuse to link against libraries not in the store by setting the
7011 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
7013 The package @code{gfortran-toolchain} provides a complete GCC toolchain
7014 for Fortran development. For other languages, please use
7015 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
7018 @node Invoking guix git authenticate
7019 @section Invoking @command{guix git authenticate}
7021 The @command{guix git authenticate} command authenticates a Git checkout
7022 following the same rule as for channels (@pxref{channel-authentication,
7023 channel authentication}). That is, starting from a given commit, it
7024 ensures that all subsequent commits are signed by an OpenPGP key whose
7025 fingerprint appears in the @file{.guix-authorizations} file of its
7028 You will find this command useful if you maintain a channel. But in
7029 fact, this authentication mechanism is useful in a broader context, so
7030 you might want to use it for Git repositories that have nothing to do
7033 The general syntax is:
7036 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
7039 By default, this command authenticates the Git checkout in the current
7040 directory; it outputs nothing and exits with exit code zero on success
7041 and non-zero on failure. @var{commit} above denotes the first commit
7042 where authentication takes place, and @var{signer} is the OpenPGP
7043 fingerprint of public key used to sign @var{commit}. Together, they
7044 form a ``channel introduction'' (@pxref{channel-authentication, channel
7045 introduction}). The options below allow you to fine-tune the process.
7048 @item --repository=@var{directory}
7049 @itemx -r @var{directory}
7050 Open the Git repository in @var{directory} instead of the current
7053 @item --keyring=@var{reference}
7054 @itemx -k @var{reference}
7055 Load OpenPGP keyring from @var{reference}, the reference of a branch
7056 such as @code{origin/keyring} or @code{my-keyring}. The branch must
7057 contain OpenPGP public keys in @file{.key} files, either in binary form
7058 or ``ASCII-armored''. By default the keyring is loaded from the branch
7059 named @code{keyring}.
7062 Display commit signing statistics upon completion.
7064 @item --cache-key=@var{key}
7065 Previously-authenticated commits are cached in a file under
7066 @file{~/.cache/guix/authentication}. This option forces the cache to be
7067 stored in file @var{key} in that directory.
7069 @item --historical-authorizations=@var{file}
7070 By default, any commit whose parent commit(s) lack the
7071 @file{.guix-authorizations} file is considered inauthentic. In
7072 contrast, this option considers the authorizations in @var{file} for any
7073 commit that lacks @file{.guix-authorizations}. The format of @var{file}
7074 is the same as that of @file{.guix-authorizations}
7075 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
7079 @c *********************************************************************
7080 @node Programming Interface
7081 @chapter Programming Interface
7083 GNU Guix provides several Scheme programming interfaces (APIs) to
7084 define, build, and query packages. The first interface allows users to
7085 write high-level package definitions. These definitions refer to
7086 familiar packaging concepts, such as the name and version of a package,
7087 its build system, and its dependencies. These definitions can then be
7088 turned into concrete build actions.
7090 Build actions are performed by the Guix daemon, on behalf of users. In a
7091 standard setup, the daemon has write access to the store---the
7092 @file{/gnu/store} directory---whereas users do not. The recommended
7093 setup also has the daemon perform builds in chroots, under specific
7094 build users, to minimize interference with the rest of the system.
7097 Lower-level APIs are available to interact with the daemon and the
7098 store. To instruct the daemon to perform a build action, users actually
7099 provide it with a @dfn{derivation}. A derivation is a low-level
7100 representation of the build actions to be taken, and the environment in
7101 which they should occur---derivations are to package definitions what
7102 assembly is to C programs. The term ``derivation'' comes from the fact
7103 that build results @emph{derive} from them.
7105 This chapter describes all these APIs in turn, starting from high-level
7106 package definitions.
7109 * Package Modules:: Packages from the programmer's viewpoint.
7110 * Defining Packages:: Defining new packages.
7111 * Defining Package Variants:: Customizing packages.
7112 * Writing Manifests:: The bill of materials of your environment.
7113 * Build Systems:: Specifying how packages are built.
7114 * Build Phases:: Phases of the build process of a package.
7115 * Build Utilities:: Helpers for your package definitions and more.
7116 * Search Paths:: Declaring search path environment variables.
7117 * The Store:: Manipulating the package store.
7118 * Derivations:: Low-level interface to package derivations.
7119 * The Store Monad:: Purely functional interface to the store.
7120 * G-Expressions:: Manipulating build expressions.
7121 * Invoking guix repl:: Programming Guix in Guile
7122 * Using Guix Interactively:: Fine-grain interaction at the REPL.
7125 @node Package Modules
7126 @section Package Modules
7128 From a programming viewpoint, the package definitions of the
7129 GNU distribution are provided by Guile modules in the @code{(gnu packages
7130 @dots{})} name space@footnote{Note that packages under the @code{(gnu
7131 packages @dots{})} module name space are not necessarily ``GNU
7132 packages''. This module naming scheme follows the usual Guile module
7133 naming convention: @code{gnu} means that these modules are distributed
7134 as part of the GNU system, and @code{packages} identifies modules that
7135 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
7136 Reference Manual}). For instance, the @code{(gnu packages emacs)}
7137 module exports a variable named @code{emacs}, which is bound to a
7138 @code{<package>} object (@pxref{Defining Packages}).
7140 The @code{(gnu packages @dots{})} module name space is
7141 automatically scanned for packages by the command-line tools. For
7142 instance, when running @code{guix install emacs}, all the @code{(gnu
7143 packages @dots{})} modules are scanned until one that exports a package
7144 object whose name is @code{emacs} is found. This package search
7145 facility is implemented in the @code{(gnu packages)} module.
7147 @cindex customization, of packages
7148 @cindex package module search path
7149 Users can store package definitions in modules with different
7150 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
7151 name and module name must match. For instance, the @code{(my-packages
7152 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
7153 relative to the load path specified with @option{--load-path} or
7154 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
7155 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
7156 these package definitions visible to the user interfaces:
7160 By adding the directory containing your package modules to the search path
7161 with the @code{-L} flag of @command{guix package} and other commands
7162 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
7163 environment variable described below.
7166 By defining a @dfn{channel} and configuring @command{guix pull} so that it
7167 pulls from it. A channel is essentially a Git repository containing package
7168 modules. @xref{Channels}, for more information on how to define and use
7172 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
7174 @defvr {Environment Variable} GUIX_PACKAGE_PATH
7175 This is a colon-separated list of directories to search for additional
7176 package modules. Directories listed in this variable take precedence
7177 over the own modules of the distribution.
7180 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
7181 each package is built based solely on other packages in the
7182 distribution. The root of this dependency graph is a small set of
7183 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
7184 bootstrap)} module. For more information on bootstrapping,
7185 @pxref{Bootstrapping}.
7187 @node Defining Packages
7188 @section Defining Packages
7190 The high-level interface to package definitions is implemented in the
7191 @code{(guix packages)} and @code{(guix build-system)} modules. As an
7192 example, the package definition, or @dfn{recipe}, for the GNU Hello
7193 package looks like this:
7196 (define-module (gnu packages hello)
7197 #:use-module (guix packages)
7198 #:use-module (guix download)
7199 #:use-module (guix build-system gnu)
7200 #:use-module (guix licenses)
7201 #:use-module (gnu packages gawk))
7203 (define-public hello
7209 (uri (string-append "mirror://gnu/hello/hello-" version
7213 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
7214 (build-system gnu-build-system)
7215 (arguments '(#:configure-flags '("--enable-silent-rules")))
7216 (inputs (list gawk))
7217 (synopsis "Hello, GNU world: An example GNU package")
7218 (description "Guess what GNU Hello prints!")
7219 (home-page "https://www.gnu.org/software/hello/")
7224 Without being a Scheme expert, the reader may have guessed the meaning
7225 of the various fields here. This expression binds the variable
7226 @code{hello} to a @code{<package>} object, which is essentially a record
7227 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
7228 This package object can be inspected using procedures found in the
7229 @code{(guix packages)} module; for instance, @code{(package-name hello)}
7230 returns---surprise!---@code{"hello"}.
7232 With luck, you may be able to import part or all of the definition of
7233 the package you are interested in from another repository, using the
7234 @code{guix import} command (@pxref{Invoking guix import}).
7236 In the example above, @code{hello} is defined in a module of its own,
7237 @code{(gnu packages hello)}. Technically, this is not strictly
7238 necessary, but it is convenient to do so: all the packages defined in
7239 modules under @code{(gnu packages @dots{})} are automatically known to
7240 the command-line tools (@pxref{Package Modules}).
7242 There are a few points worth noting in the above package definition:
7246 The @code{source} field of the package is an @code{<origin>} object
7247 (@pxref{origin Reference}, for the complete reference).
7248 Here, the @code{url-fetch} method from @code{(guix download)} is used,
7249 meaning that the source is a file to be downloaded over FTP or HTTP.
7251 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
7252 the GNU mirrors defined in @code{(guix download)}.
7254 The @code{sha256} field specifies the expected SHA256 hash of the file
7255 being downloaded. It is mandatory, and allows Guix to check the
7256 integrity of the file. The @code{(base32 @dots{})} form introduces the
7257 base32 representation of the hash. You can obtain this information with
7258 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
7259 hash} (@pxref{Invoking guix hash}).
7262 When needed, the @code{origin} form can also have a @code{patches} field
7263 listing patches to be applied, and a @code{snippet} field giving a
7264 Scheme expression to modify the source code.
7267 @cindex GNU Build System
7268 The @code{build-system} field specifies the procedure to build the
7269 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
7270 represents the familiar GNU Build System, where packages may be
7271 configured, built, and installed with the usual @code{./configure &&
7272 make && make check && make install} command sequence.
7274 When you start packaging non-trivial software, you may need tools to
7275 manipulate those build phases, manipulate files, and so on. @xref{Build
7276 Utilities}, for more on this.
7279 The @code{arguments} field specifies options for the build system
7280 (@pxref{Build Systems}). Here it is interpreted by
7281 @code{gnu-build-system} as a request run @file{configure} with the
7282 @option{--enable-silent-rules} flag.
7288 @cindex backquote (quasiquote)
7291 @cindex comma (unquote)
7294 What about these quote (@code{'}) characters? They are Scheme syntax to
7295 introduce a literal list; @code{'} is synonymous with @code{quote}.
7296 Sometimes you'll also see @code{`} (a backquote, synonymous with
7297 @code{quasiquote}) and @code{,} (a comma, synonymous with @code{unquote}).
7298 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
7299 for details. Here the value of the @code{arguments} field is a list of
7300 arguments passed to the build system down the road, as with @code{apply}
7301 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
7304 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
7305 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
7306 @code{#:configure-flags} is a keyword used to pass a keyword argument
7307 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
7311 The @code{inputs} field specifies inputs to the build process---i.e.,
7312 build-time or run-time dependencies of the package. Here, we add
7313 an input, a reference to the @code{gawk}
7314 variable; @code{gawk} is itself bound to a @code{<package>} object.
7316 Note that GCC, Coreutils, Bash, and other essential tools do not need to
7317 be specified as inputs here. Instead, @code{gnu-build-system} takes care
7318 of ensuring that they are present (@pxref{Build Systems}).
7320 However, any other dependencies need to be specified in the
7321 @code{inputs} field. Any dependency not specified here will simply be
7322 unavailable to the build process, possibly leading to a build failure.
7325 @xref{package Reference}, for a full description of possible fields.
7327 @quotation Going further
7328 @cindex Scheme programming language, getting started
7329 Intimidated by the Scheme language or curious about it? The Cookbook
7330 has a short section to get started that recaps some of the things shown
7331 above and explains the fundamentals. @xref{A Scheme Crash Course,,,
7332 guix-cookbook, GNU Guix Cookbook}, for more information.
7335 Once a package definition is in place, the
7336 package may actually be built using the @code{guix build} command-line
7337 tool (@pxref{Invoking guix build}), troubleshooting any build failures
7338 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
7339 package definition using the @command{guix edit} command
7340 (@pxref{Invoking guix edit}).
7341 @xref{Packaging Guidelines}, for
7342 more information on how to test package definitions, and
7343 @ref{Invoking guix lint}, for information on how to check a definition
7344 for style conformance.
7345 @vindex GUIX_PACKAGE_PATH
7346 Lastly, @pxref{Channels}, for information
7347 on how to extend the distribution by adding your own package definitions
7350 Finally, updating the package definition to a new upstream version
7351 can be partly automated by the @command{guix refresh} command
7352 (@pxref{Invoking guix refresh}).
7354 Behind the scenes, a derivation corresponding to the @code{<package>}
7355 object is first computed by the @code{package-derivation} procedure.
7356 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
7357 The build actions it prescribes may then be realized by using the
7358 @code{build-derivations} procedure (@pxref{The Store}).
7360 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
7361 Return the @code{<derivation>} object of @var{package} for @var{system}
7362 (@pxref{Derivations}).
7364 @var{package} must be a valid @code{<package>} object, and @var{system}
7365 must be a string denoting the target system type---e.g.,
7366 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
7367 must be a connection to the daemon, which operates on the store
7368 (@pxref{The Store}).
7372 @cindex cross-compilation
7373 Similarly, it is possible to compute a derivation that cross-builds a
7374 package for some other system:
7376 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
7377 @var{package} @var{target} [@var{system}]
7378 Return the @code{<derivation>} object of @var{package} cross-built from
7379 @var{system} to @var{target}.
7381 @var{target} must be a valid GNU triplet denoting the target hardware
7382 and operating system, such as @code{"aarch64-linux-gnu"}
7383 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
7386 Once you have package definitions, you can easily define @emph{variants}
7387 of those packages. @xref{Defining Package Variants}, for more on that.
7390 * package Reference:: The package data type.
7391 * origin Reference:: The origin data type.
7395 @node package Reference
7396 @subsection @code{package} Reference
7398 This section summarizes all the options available in @code{package}
7399 declarations (@pxref{Defining Packages}).
7401 @deftp {Data Type} package
7402 This is the data type representing a package recipe.
7406 The name of the package, as a string.
7408 @item @code{version}
7409 The version of the package, as a string. @xref{Version Numbers}, for
7413 An object telling how the source code for the package should be
7414 acquired. Most of the time, this is an @code{origin} object, which
7415 denotes a file fetched from the Internet (@pxref{origin Reference}). It
7416 can also be any other ``file-like'' object such as a @code{local-file},
7417 which denotes a file from the local file system (@pxref{G-Expressions,
7418 @code{local-file}}).
7420 @item @code{build-system}
7421 The build system that should be used to build the package (@pxref{Build
7424 @item @code{arguments} (default: @code{'()})
7425 The arguments that should be passed to the build system (@pxref{Build
7426 Systems}). This is a list, typically containing sequential
7427 keyword-value pairs, as in this example:
7432 ;; several fields omitted
7434 (list #:tests? #f ;skip tests
7435 #:make-flags #~'("VERBOSE=1") ;pass flags to 'make'
7436 #:configure-flags #~'("--enable-frobbing"))))
7439 The exact set of supported keywords depends on the build system
7440 (@pxref{Build Systems}), but you will find that almost all of them honor
7441 @code{#:configure-flags}, @code{#:make-flags}, @code{#:tests?}, and
7442 @code{#:phases}. The @code{#:phases} keyword in particular lets you
7443 modify the set of build phases for your package (@pxref{Build Phases}).
7445 @item @code{inputs} (default: @code{'()})
7446 @itemx @code{native-inputs} (default: @code{'()})
7447 @itemx @code{propagated-inputs} (default: @code{'()})
7448 @cindex inputs, of packages
7449 These fields list dependencies of the package. Each element of these
7450 lists is either a package, origin, or other ``file-like object''
7451 (@pxref{G-Expressions}); to specify the output of that file-like object
7452 that should be used, pass a two-element list where the second element is
7453 the output (@pxref{Packages with Multiple Outputs}, for more on package
7454 outputs). For example, the list below specifies three inputs:
7457 (list libffi libunistring
7458 `(,glib "bin")) ;the "bin" output of GLib
7461 In the example above, the @code{"out"} output of @code{libffi} and
7462 @code{libunistring} is used.
7464 @quotation Compatibility Note
7465 Until version 1.3.0, input lists were a list of tuples,
7466 where each tuple has a label for the input (a string) as its
7467 first element, a package, origin, or derivation as its second element,
7468 and optionally the name of the output thereof that should be used, which
7469 defaults to @code{"out"}. For example, the list below is equivalent to
7470 the one above, but using the @dfn{old input style}:
7473 ;; Old input style (deprecated).
7474 `(("libffi" ,libffi)
7475 ("libunistring" ,libunistring)
7476 ("glib:bin" ,glib "bin")) ;the "bin" output of GLib
7479 This style is now deprecated; it is still supported but support will be
7480 removed in a future version. It should not be used for new package
7481 definitions. @xref{Invoking guix style}, on how to migrate to the new
7485 @cindex cross compilation, package dependencies
7486 The distinction between @code{native-inputs} and @code{inputs} is
7487 necessary when considering cross-compilation. When cross-compiling,
7488 dependencies listed in @code{inputs} are built for the @emph{target}
7489 architecture; conversely, dependencies listed in @code{native-inputs}
7490 are built for the architecture of the @emph{build} machine.
7492 @code{native-inputs} is typically used to list tools needed at
7493 build time, but not at run time, such as Autoconf, Automake, pkg-config,
7494 Gettext, or Bison. @command{guix lint} can report likely mistakes in
7495 this area (@pxref{Invoking guix lint}).
7497 @anchor{package-propagated-inputs}
7498 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
7499 specified packages will be automatically installed to profiles
7500 (@pxref{Features, the role of profiles in Guix}) alongside the package
7501 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
7502 package}}, for information on how @command{guix package} deals with
7505 For example this is necessary when packaging a C/C++ library that needs
7506 headers of another library to compile, or when a pkg-config file refers
7507 to another one @i{via} its @code{Requires} field.
7509 Another example where @code{propagated-inputs} is useful is for languages
7510 that lack a facility to record the run-time search path akin to the
7511 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
7512 more. When packaging libraries written in those languages, ensure they
7513 can find library code they depend on at run time by listing run-time
7514 dependencies in @code{propagated-inputs} rather than @code{inputs}.
7516 @item @code{outputs} (default: @code{'("out")})
7517 The list of output names of the package. @xref{Packages with Multiple
7518 Outputs}, for typical uses of additional outputs.
7520 @item @code{native-search-paths} (default: @code{'()})
7521 @itemx @code{search-paths} (default: @code{'()})
7522 A list of @code{search-path-specification} objects describing
7523 search-path environment variables honored by the package. @xref{Search
7524 Paths}, for more on search path specifications.
7526 As for inputs, the distinction between @code{native-search-paths} and
7527 @code{search-paths} only matters when cross-compiling. In a
7528 cross-compilation context, @code{native-search-paths} applies
7529 exclusively to native inputs whereas @code{search-paths} applies only to
7532 Packages such as cross-compilers care about target inputs---for
7533 instance, our (modified) GCC cross-compiler has
7534 @env{CROSS_C_INCLUDE_PATH} in @code{search-paths}, which allows it to
7535 pick @file{.h} files for the target system and @emph{not} those of
7536 native inputs. For the majority of packages though, only
7537 @code{native-search-paths} makes sense.
7539 @item @code{replacement} (default: @code{#f})
7540 This must be either @code{#f} or a package object that will be used as a
7541 @dfn{replacement} for this package. @xref{Security Updates, grafts},
7544 @item @code{synopsis}
7545 A one-line description of the package.
7547 @item @code{description}
7548 A more elaborate description of the package, as a string in Texinfo
7551 @item @code{license}
7552 @cindex license, of packages
7553 The license of the package; a value from @code{(guix licenses)},
7554 or a list of such values.
7556 @item @code{home-page}
7557 The URL to the home-page of the package, as a string.
7559 @item @code{supported-systems} (default: @code{%supported-systems})
7560 The list of systems supported by the package, as strings of the form
7561 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
7563 @item @code{location} (default: source location of the @code{package} form)
7564 The source location of the package. It is useful to override this when
7565 inheriting from another package, in which case this field is not
7566 automatically corrected.
7570 @deffn {Scheme Syntax} this-package
7571 When used in the @emph{lexical scope} of a package field definition, this
7572 identifier resolves to the package being defined.
7574 The example below shows how to add a package as a native input of itself when
7582 ;; When cross-compiled, Guile, for example, depends on
7583 ;; a native version of itself. Add it here.
7584 (native-inputs (if (%current-target-system)
7589 It is an error to refer to @code{this-package} outside a package definition.
7592 The following helper procedures are provided to help deal with package
7595 @deffn {Scheme Procedure} lookup-package-input @var{package} @var{name}
7596 @deffnx {Scheme Procedure} lookup-package-native-input @var{package} @var{name}
7597 @deffnx {Scheme Procedure} lookup-package-propagated-input @var{package} @var{name}
7598 @deffnx {Scheme Procedure} lookup-package-direct-input @var{package} @var{name}
7599 Look up @var{name} among @var{package}'s inputs (or native, propagated,
7600 or direct inputs). Return it if found, @code{#f} otherwise.
7602 @var{name} is the name of a package depended on. Here's how you might
7606 (use-modules (guix packages) (gnu packages base))
7608 (lookup-package-direct-input coreutils "gmp")
7609 @result{} #<package gmp@@6.2.1 @dots{}>
7612 In this example we obtain the @code{gmp} package that is among the
7613 direct inputs of @code{coreutils}.
7616 @cindex development inputs, of a package
7617 @cindex implicit inputs, of a package
7618 Sometimes you will want to obtain the list of inputs needed to
7619 @emph{develop} a package---all the inputs that are visible when the
7620 package is compiled. This is what the @code{package-development-inputs}
7623 @deffn {Scheme Procedure} package-development-inputs @var{package} @
7624 [@var{system}] [#:target #f]
7625 Return the list of inputs required by @var{package} for development
7626 purposes on @var{system}. When @var{target} is true, return the inputs
7627 needed to cross-compile @var{package} from @var{system} to
7628 @var{target}, where @var{target} is a triplet such as
7629 @code{"aarch64-linux-gnu"}.
7631 Note that the result includes both explicit inputs and implicit
7632 inputs---inputs automatically added by the build system (@pxref{Build
7633 Systems}). Let us take the @code{hello} package to illustrate that:
7636 (use-modules (gnu packages base) (guix packages))
7639 @result{} #<package hello@@2.10 gnu/packages/base.scm:79 7f585d4f6790>
7641 (package-direct-inputs hello)
7644 (package-development-inputs hello)
7645 @result{} (("source" @dots{}) ("tar" #<package tar@@1.32 @dots{}>) @dots{})
7648 In this example, @code{package-direct-inputs} returns the empty list,
7649 because @code{hello} has zero explicit dependencies. Conversely,
7650 @code{package-development-inputs} includes inputs implicitly added by
7651 @code{gnu-build-system} that are required to build @code{hello}: tar,
7652 gzip, GCC, libc, Bash, and more. To visualize it, @command{guix graph
7653 hello} would show you explicit inputs, whereas @command{guix graph -t
7654 bag hello} would include implicit inputs (@pxref{Invoking guix graph}).
7657 Because packages are regular Scheme objects that capture a complete
7658 dependency graph and associated build procedures, it is often useful to
7659 write procedures that take a package and return a modified version
7660 thereof according to some parameters. Below are a few examples.
7662 @cindex tool chain, choosing a package's tool chain
7663 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
7664 Return a variant of @var{package} that uses @var{toolchain} instead of
7665 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
7666 inputs (label/package tuples) providing equivalent functionality, such
7667 as the @code{gcc-toolchain} package.
7669 The example below returns a variant of the @code{hello} package built
7670 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
7671 GNU C Library) instead of the default tool chain:
7674 (let ((toolchain (specification->package "gcc-toolchain@@10")))
7675 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
7678 The build tool chain is part of the @dfn{implicit inputs} of
7679 packages---it's usually not listed as part of the various ``inputs''
7680 fields and is instead pulled in by the build system. Consequently, this
7681 procedure works by changing the build system of @var{package} so that it
7682 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
7683 for more on build systems.
7686 @node origin Reference
7687 @subsection @code{origin} Reference
7689 This section documents @dfn{origins}. An @code{origin} declaration
7690 specifies data that must be ``produced''---downloaded, usually---and
7691 whose content hash is known in advance. Origins are primarily used to
7692 represent the source code of packages (@pxref{Defining Packages}). For
7693 that reason, the @code{origin} form allows you to declare patches to
7694 apply to the original source code as well as code snippets to modify it.
7696 @deftp {Data Type} origin
7697 This is the data type representing a source code origin.
7701 An object containing the URI of the source. The object type depends on
7702 the @code{method} (see below). For example, when using the
7703 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
7704 values are: a URL represented as a string, or a list thereof.
7706 @cindex fixed-output derivations, for download
7708 A monadic procedure that handles the given URI@. The procedure must
7709 accept at least three arguments: the value of the @code{uri} field and
7710 the hash algorithm and hash value specified by the @code{hash} field.
7711 It must return a store item or a derivation in the store monad
7712 (@pxref{The Store Monad}); most methods return a fixed-output derivation
7713 (@pxref{Derivations}).
7715 Commonly used methods include @code{url-fetch}, which fetches data from
7716 a URL, and @code{git-fetch}, which fetches data from a Git repository
7720 A bytevector containing the SHA-256 hash of the source. This is
7721 equivalent to providing a @code{content-hash} SHA256 object in the
7722 @code{hash} field described below.
7725 The @code{content-hash} object of the source---see below for how to use
7726 @code{content-hash}.
7728 You can obtain this information using @code{guix download}
7729 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
7732 @item @code{file-name} (default: @code{#f})
7733 The file name under which the source code should be saved. When this is
7734 @code{#f}, a sensible default value will be used in most cases. In case
7735 the source is fetched from a URL, the file name from the URL will be
7736 used. For version control checkouts, it is recommended to provide the
7737 file name explicitly because the default is not very descriptive.
7739 @item @code{patches} (default: @code{'()})
7740 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
7741 file-like objects}) pointing to patches to be applied to the source.
7743 This list of patches must be unconditional. In particular, it cannot
7744 depend on the value of @code{%current-system} or
7745 @code{%current-target-system}.
7747 @item @code{snippet} (default: @code{#f})
7748 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
7749 in the source directory. This is a convenient way to modify the source,
7750 sometimes more convenient than a patch.
7752 @item @code{patch-flags} (default: @code{'("-p1")})
7753 A list of command-line flags that should be passed to the @code{patch}
7756 @item @code{patch-inputs} (default: @code{#f})
7757 Input packages or derivations to the patching process. When this is
7758 @code{#f}, the usual set of inputs necessary for patching are provided,
7759 such as GNU@tie{}Patch.
7761 @item @code{modules} (default: @code{'()})
7762 A list of Guile modules that should be loaded during the patching
7763 process and while running the code in the @code{snippet} field.
7765 @item @code{patch-guile} (default: @code{#f})
7766 The Guile package that should be used in the patching process. When
7767 this is @code{#f}, a sensible default is used.
7771 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
7772 Construct a content hash object for the given @var{algorithm}, and with
7773 @var{value} as its hash value. When @var{algorithm} is omitted, assume
7774 it is @code{sha256}.
7776 @var{value} can be a literal string, in which case it is base32-decoded,
7777 or it can be a bytevector.
7779 The following forms are all equivalent:
7782 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
7783 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
7785 (content-hash (base32
7786 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
7787 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
7791 Technically, @code{content-hash} is currently implemented as a macro.
7792 It performs sanity checks at macro-expansion time, when possible, such
7793 as ensuring that @var{value} has the right size for @var{algorithm}.
7796 As we have seen above, how exactly the data an origin refers to is
7797 retrieved is determined by its @code{method} field. The @code{(guix
7798 download)} module provides the most common method, @code{url-fetch},
7801 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
7802 [name] [#:executable? #f]
7803 Return a fixed-output derivation that fetches data from @var{url} (a
7804 string, or a list of strings denoting alternate URLs), which is expected
7805 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
7806 the file name is the base name of URL; optionally, @var{name} can
7807 specify a different file name. When @var{executable?} is true, make the
7808 downloaded file executable.
7810 When one of the URL starts with @code{mirror://}, then its host part is
7811 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
7813 Alternatively, when URL starts with @code{file://}, return the
7814 corresponding file name in the store.
7817 Likewise, the @code{(guix git-download)} module defines the
7818 @code{git-fetch} origin method, which fetches data from a Git version
7819 control repository, and the @code{git-reference} data type to describe
7820 the repository and revision to fetch.
7822 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
7823 Return a fixed-output derivation that fetches @var{ref}, a
7824 @code{<git-reference>} object. The output is expected to have recursive
7825 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7826 the file name, or a generic name if @code{#f}.
7829 @deftp {Data Type} git-reference
7830 This data type represents a Git reference for @code{git-fetch} to
7835 The URL of the Git repository to clone.
7838 This string denotes either the commit to fetch (a hexadecimal string),
7839 or the tag to fetch. You can also use a ``short'' commit ID or a
7840 @command{git describe} style identifier such as
7841 @code{v1.0.1-10-g58d7909c97}.
7843 @item @code{recursive?} (default: @code{#f})
7844 This Boolean indicates whether to recursively fetch Git sub-modules.
7847 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
7852 (url "https://git.savannah.gnu.org/git/hello.git")
7856 This is equivalent to the reference below, which explicitly names the
7861 (url "https://git.savannah.gnu.org/git/hello.git")
7862 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
7866 For Mercurial repositories, the module @code{(guix hg-download)} defines
7867 the @code{hg-fetch} origin method and @code{hg-reference} data type for
7868 support of the Mercurial version control system.
7870 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
7872 Return a fixed-output derivation that fetches @var{ref}, a
7873 @code{<hg-reference>} object. The output is expected to have recursive
7874 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7875 the file name, or a generic name if @code{#false}.
7878 @node Defining Package Variants
7879 @section Defining Package Variants
7881 @cindex customizing packages
7882 @cindex variants, of packages
7883 One of the nice things with Guix is that, given a package definition,
7884 you can easily @emph{derive} variants of that package---for a different
7885 upstream version, with different dependencies, different compilation
7886 options, and so on. Some of these custom packages can be defined
7887 straight from the command line (@pxref{Package Transformation Options}).
7888 This section describes how to define package variants in code. This can
7889 be useful in ``manifests'' (@pxref{Writing Manifests})
7890 and in your own package collection
7891 (@pxref{Creating a Channel}), among others!
7893 @cindex inherit, for package definitions
7894 As discussed earlier, packages are first-class objects in the Scheme
7895 language. The @code{(guix packages)} module provides the @code{package}
7896 construct to define new package objects (@pxref{package Reference}).
7897 The easiest way to define a package variant is using the @code{inherit}
7898 keyword together with @code{package}. This allows you to inherit from a
7899 package definition while overriding the fields you want.
7901 For example, given the @code{hello} variable, which contains a
7902 definition for the current version of GNU@tie{}Hello, here's how you
7903 would define a variant for version 2.2 (released in 2006, it's
7907 (use-modules (gnu packages base)) ;for 'hello'
7915 (uri (string-append "mirror://gnu/hello/hello-" version
7919 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
7922 The example above corresponds to what the @option{--with-source} package
7923 transformation option does. Essentially @code{hello-2.2} preserves all
7924 the fields of @code{hello}, except @code{version} and @code{source},
7925 which it overrides. Note that the original @code{hello} variable is
7926 still there, in the @code{(gnu packages base)} module, unchanged. When
7927 you define a custom package like this, you are really @emph{adding} a
7928 new package definition; the original one remains available.
7930 You can just as well define variants with a different set of
7931 dependencies than the original package. For example, the default
7932 @code{gdb} package depends on @code{guile}, but since that is an
7933 optional dependency, you can define a variant that removes that
7937 (use-modules (gnu packages gdb)) ;for 'gdb'
7939 (define gdb-sans-guile
7942 (inputs (modify-inputs (package-inputs gdb)
7943 (delete "guile")))))
7946 The @code{modify-inputs} form above removes the @code{"guile"} package
7947 from the @code{inputs} field of @code{gdb}. The @code{modify-inputs}
7948 macro is a helper that can prove useful anytime you want to remove, add,
7949 or replace package inputs.
7951 @deffn {Scheme Syntax} modify-inputs @var{inputs} @var{clauses}
7952 Modify the given package inputs, as returned by @code{package-inputs} & co.,
7953 according to the given clauses. Each clause must have one of the
7957 @item (delete @var{name}@dots{})
7958 Delete from the inputs packages with the given @var{name}s (strings).
7960 @item (append @var{package}@dots{})
7961 Add @var{package}s to the end of the input list.
7963 @item (prepend @var{package}@dots{})
7964 Add @var{package}s to the front of the input list.
7967 The example below removes the GMP and ACL inputs of Coreutils and adds
7968 libcap to the back of the input list:
7971 (modify-inputs (package-inputs coreutils)
7972 (delete "gmp" "acl")
7976 The example below replaces the @code{guile} package from the inputs of
7977 @code{guile-redis} with @code{guile-2.2}:
7980 (modify-inputs (package-inputs guile-redis)
7981 (replace "guile" guile-2.2))
7984 The last type of clause is @code{prepend}, to add inputs to the front of
7988 In some cases, you may find it useful to write functions
7989 (``procedures'', in Scheme parlance) that return a package based on some
7990 parameters. For example, consider the @code{luasocket} library for the
7991 Lua programming language. We want to create @code{luasocket} packages
7992 for major versions of Lua. One way to do that is to define a procedure
7993 that takes a Lua package and returns a @code{luasocket} package that
7997 (define (make-lua-socket name lua)
7998 ;; Return a luasocket package built with LUA.
8002 ;; several fields omitted
8004 (synopsis "Socket library for Lua")))
8006 (define-public lua5.1-socket
8007 (make-lua-socket "lua5.1-socket" lua-5.1))
8009 (define-public lua5.2-socket
8010 (make-lua-socket "lua5.2-socket" lua-5.2))
8013 Here we have defined packages @code{lua5.1-socket} and
8014 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
8015 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
8016 more info on procedures. Having top-level public definitions for these
8017 two packages means that they can be referred to from the command line
8018 (@pxref{Package Modules}).
8020 @cindex package transformations
8021 These are pretty simple package variants. As a convenience, the
8022 @code{(guix transformations)} module provides a high-level interface
8023 that directly maps to the more sophisticated package transformation
8024 options (@pxref{Package Transformation Options}):
8026 @deffn {Scheme Procedure} options->transformation @var{opts}
8027 Return a procedure that, when passed an object to build (package,
8028 derivation, etc.), applies the transformations specified by @var{opts} and returns
8029 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
8032 ((with-branch . "guile-gcrypt=master")
8033 (without-tests . "libgcrypt"))
8036 Each symbol names a transformation and the corresponding string is an argument
8037 to that transformation.
8040 For instance, a manifest equivalent to this command:
8044 --with-branch=guile-gcrypt=master \
8045 --with-debug-info=zlib
8049 ... would look like this:
8052 (use-modules (guix transformations))
8055 ;; The package transformation procedure.
8056 (options->transformation
8057 '((with-branch . "guile-gcrypt=master")
8058 (with-debug-info . "zlib"))))
8061 (list (transform (specification->package "guix"))))
8064 @cindex input rewriting
8065 @cindex dependency graph rewriting
8066 The @code{options->transformation} procedure is convenient, but it's
8067 perhaps also not as flexible as you may like. How is it implemented?
8068 The astute reader probably noticed that most package transformation
8069 options go beyond the superficial changes shown in the first examples of
8070 this section: they involve @dfn{input rewriting}, whereby the dependency
8071 graph of a package is rewritten by replacing specific inputs by others.
8073 Dependency graph rewriting, for the purposes of swapping packages in the
8074 graph, is what the @code{package-input-rewriting} procedure in
8075 @code{(guix packages)} implements.
8077 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
8078 [@var{rewrite-name}] [#:deep? #t]
8079 Return a procedure that, when passed a package, replaces its direct and
8080 indirect dependencies, including implicit inputs when @var{deep?} is
8081 true, according to @var{replacements}. @var{replacements} is a list of
8082 package pairs; the first element of each pair is the package to replace,
8083 and the second one is the replacement.
8085 Optionally, @var{rewrite-name} is a one-argument procedure that takes
8086 the name of a package and returns its new name after rewrite.
8090 Consider this example:
8093 (define libressl-instead-of-openssl
8094 ;; This is a procedure to replace OPENSSL by LIBRESSL,
8096 (package-input-rewriting `((,openssl . ,libressl))))
8098 (define git-with-libressl
8099 (libressl-instead-of-openssl git))
8103 Here we first define a rewriting procedure that replaces @var{openssl}
8104 with @var{libressl}. Then we use it to define a @dfn{variant} of the
8105 @var{git} package that uses @var{libressl} instead of @var{openssl}.
8106 This is exactly what the @option{--with-input} command-line option does
8107 (@pxref{Package Transformation Options, @option{--with-input}}).
8109 The following variant of @code{package-input-rewriting} can match packages to
8110 be replaced by name rather than by identity.
8112 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
8113 Return a procedure that, given a package, applies the given
8114 @var{replacements} to all the package graph, including implicit inputs
8115 unless @var{deep?} is false. @var{replacements} is a list of
8116 spec/procedures pair; each spec is a package specification such as
8117 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
8118 package and returns a replacement for that package.
8121 The example above could be rewritten this way:
8124 (define libressl-instead-of-openssl
8125 ;; Replace all the packages called "openssl" with LibreSSL.
8126 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
8129 The key difference here is that, this time, packages are matched by spec and
8130 not by identity. In other words, any package in the graph that is called
8131 @code{openssl} will be replaced.
8133 A more generic procedure to rewrite a package dependency graph is
8134 @code{package-mapping}: it supports arbitrary changes to nodes in the
8137 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
8138 Return a procedure that, given a package, applies @var{proc} to all the packages
8139 depended on and returns the resulting package. The procedure stops recursion
8140 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
8141 applied to implicit inputs as well.
8144 @node Writing Manifests
8145 @section Writing Manifests
8148 @cindex bill of materials (manifests)
8149 @command{guix} commands let you specify package lists on the command
8150 line. This is convenient, but as the command line becomes longer and
8151 less trivial, it quickly becomes more convenient to have that package
8152 list in what we call a @dfn{manifest}. A manifest is some sort of a
8153 ``bill of materials'' that defines a package set. You would typically
8154 come up with a code snippet that builds the manifest, store it in a
8155 file, say @file{manifest.scm}, and then pass that file to the
8156 @option{-m} (or @option{--manifest}) option that many @command{guix}
8157 commands support. For example, here's what a manifest for a simple
8158 package set might look like:
8161 ;; Manifest for three packages.
8162 (specifications->manifest '("gcc-toolchain" "make" "git"))
8165 Once you have that manifest, you can pass it, for example, to
8166 @command{guix package} to install just those three packages to your
8167 profile (@pxref{profile-manifest, @option{-m} option of @command{guix
8171 guix package -m manifest.scm
8175 ... or you can pass it to @command{guix shell} (@pxref{shell-manifest,
8176 @command{-m} option of @command{guix shell}}) to spawn an ephemeral
8180 guix shell -m manifest.scm
8184 ... or you can pass it to @command{guix pack} in pretty much the same
8185 way (@pxref{pack-manifest, @option{-m} option of @command{guix pack}}).
8186 You can store the manifest under version control, share it with others
8187 so they can easily get set up, etc.
8189 But how do you write your first manifest? To get started, maybe you'll
8190 want to write a manifest that mirrors what you already have in a
8191 profile. Rather than start from a blank page, @command{guix package}
8192 can generate a manifest for you (@pxref{export-manifest, @command{guix
8193 package --export-manifest}}):
8196 # Write to 'manifest.scm' a manifest corresponding to the
8197 # default profile, ~/.guix-profile.
8198 guix package --export-manifest > manifest.scm
8201 Or maybe you'll want to ``translate'' command-line arguments into a
8202 manifest. In that case, @command{guix shell} can help
8203 (@pxref{shell-export-manifest, @command{guix shell --export-manifest}}):
8206 # Write a manifest for the packages specified on the command line.
8207 guix shell --export-manifest gcc-toolchain make git > manifest.scm
8210 In both cases, the @option{--export-manifest} option tries hard to
8211 generate a faithful manifest; in particular, it takes package
8212 transformation options into account (@pxref{Package Transformation
8216 Manifests are @emph{symbolic}: they refer to packages of the channels
8217 @emph{currently in use} (@pxref{Channels}). In the example above,
8218 @code{gcc-toolchain} might refer to version 11 today, but it might refer
8219 to version 13 two years from now.
8221 If you want to ``pin'' your software environment to specific package
8222 versions and variants, you need an additional piece of information: the
8223 list of channel revisions in use, as returned by @command{guix
8224 describe}. @xref{Replicating Guix}, for more information.
8227 Once you've obtained your first manifest, perhaps you'll want to
8228 customize it. Since your manifest is code, you now have access to all
8229 the Guix programming interfaces!
8231 Let's assume you want a manifest to deploy a custom variant of GDB, the
8232 GNU Debugger, that does not depend on Guile, together with another
8233 package. Building on the example seen in the previous section
8234 (@pxref{Defining Package Variants}), you can write a manifest along
8238 (use-modules (guix packages)
8239 (gnu packages gdb) ;for 'gdb'
8240 (gnu packages version-control)) ;for 'git'
8242 ;; Define a variant of GDB without a dependency on Guile.
8243 (define gdb-sans-guile
8246 (inputs (modify-inputs (package-inputs gdb)
8247 (delete "guile")))))
8249 ;; Return a manifest containing that one package plus Git.
8250 (packages->manifest (list gdb-sans-guile git))
8253 Note that in this example, the manifest directly refers to the
8254 @code{gdb} and @code{git} variables, which are bound to a @code{package}
8255 object (@pxref{package Reference}), instead of calling
8256 @code{specifications->manifest} to look up packages by name as we did
8257 before. The @code{use-modules} form at the top lets us access the core
8258 package interface (@pxref{Defining Packages}) and the modules that
8259 define @code{gdb} and @code{git} (@pxref{Package Modules}). Seamlessly,
8260 we're weaving all this together---the possibilities are endless, unleash
8263 The data type for manifests as well as supporting procedures are defined
8264 in the @code{(guix profiles)} module, which is automatically available
8265 to code passed to @option{-m}. The reference follows.
8267 @deftp {Data Type} manifest
8268 Data type representing a manifest.
8270 It currently has one field:
8274 This must be a list of @code{manifest-entry} records---see below.
8278 @deftp {Data Type} manifest-entry
8279 Data type representing a manifest entry. A manifest entry contains
8280 essential metadata: a name and version string, the object (usually a
8281 package) for that entry, the desired output (@pxref{Packages with
8282 Multiple Outputs}), and a number of optional pieces of information
8285 Most of the time, you won't build a manifest entry directly; instead,
8286 you will pass a package to @code{package->manifest-entry}, described
8287 below. In some unusual cases though, you might want to create manifest
8288 entries for things that are @emph{not} packages, as in this example:
8291 ;; Manually build a single manifest entry for a non-package object.
8292 (let ((hello (program-file "hello" #~(display "Hi!"))))
8297 (computed-file "hello-directory"
8298 #~(let ((bin (string-append #$output "/bin")))
8299 (mkdir #$output) (mkdir bin)
8301 (string-append bin "/hello")))))))
8304 The available fields are the following:
8308 @itemx @code{version}
8309 Name and version string for this entry.
8312 A package or other file-like object (@pxref{G-Expressions, file-like
8315 @item @code{output} (default: @code{"out"})
8316 Output of @code{item} to use, in case @code{item} has multiple outputs
8317 (@pxref{Packages with Multiple Outputs}).
8319 @item @code{dependencies} (default: @code{'()})
8320 List of manifest entries this entry depends on. When building a
8321 profile, dependencies are added to the profile.
8323 Typically, the propagated inputs of a package (@pxref{package Reference,
8324 @code{propagated-inputs}}) end up having a corresponding manifest entry
8325 in among the dependencies of the package's own manifest entry.
8327 @item @code{search-paths} (default: @code{'()})
8328 The list of search path specifications honored by this entry
8329 (@pxref{Search Paths}).
8331 @item @code{properties} (default: @code{'()})
8332 List of symbol/value pairs. When building a profile, those properties
8335 This can be used to piggyback additional metadata---e.g., the
8336 transformations applied to a package (@pxref{Package Transformation
8339 @item @code{parent} (default: @code{(delay #f)})
8340 A promise pointing to the ``parent'' manifest entry.
8342 This is used as a hint to provide context when reporting an error
8343 related to a manifest entry coming from a @code{dependencies} field.
8347 @deffn {Scheme Procedure} concatenate-manifests @var{lst}
8348 Concatenate the manifests listed in @var{lst} and return the resulting
8352 @c TODO: <manifest-pattern>, manifest-lookup, manifest-remove, etc.
8354 @deffn {Scheme Procedure} package->manifest-entry @var{package} @
8355 [@var{output}] [#:properties]
8356 Return a manifest entry for the @var{output} of package @var{package},
8357 where @var{output} defaults to @code{"out"}, and with the given
8358 @var{properties}. By default @var{properties} is the empty list or, if
8359 one or more package transformations were applied to @var{package}, it is
8360 an association list representing those transformations, suitable as an
8361 argument to @code{options->transformation} (@pxref{Defining Package
8362 Variants, @code{options->transformation}}).
8364 The code snippet below builds a manifest with an entry for the default
8365 output and the @code{send-email} output of the @code{git} package:
8368 (use-modules (gnu packages version-control))
8370 (manifest (list (package->manifest-entry git)
8371 (package->manifest-entry git "send-email")))
8375 @deffn {Scheme Procedure} packages->manifest @var{packages}
8376 Return a list of manifest entries, one for each item listed in
8377 @var{packages}. Elements of @var{packages} can be either package
8378 objects or package/string tuples denoting a specific output of a
8381 Using this procedure, the manifest above may be rewritten more
8385 (use-modules (gnu packages version-control))
8387 (packages->manifest (list git `(,git "send-email")))
8391 @anchor{package-development-manifest}
8392 @deffn {Scheme Procedure} package->development-manifest @var{package} @
8393 [@var{system}] [#:target]
8394 Return a manifest for the @dfn{development inputs} of @var{package} for
8395 @var{system}, optionally when cross-compiling to @var{target}.
8396 Development inputs include both explicit and implicit inputs of
8399 Like the @option{-D} option of @command{guix shell}
8400 (@pxref{shell-development-option, @command{guix shell -D}}), the
8401 resulting manifest describes the environment in which one can develop
8402 @var{package}. For example, suppose you're willing to set up a
8403 development environment for Inkscape, with the addition of Git for
8404 version control; you can describe that ``bill of materials'' with the
8408 (use-modules (gnu packages inkscape) ;for 'inkscape'
8409 (gnu packages version-control)) ;for 'git'
8411 (concatenate-manifests
8412 (list (package->development-manifest inkscape)
8413 (packages->manifest (list git))))
8416 In this example, the development manifest that
8417 @code{package->development-manifest} returns includes the compiler
8418 (GCC), the many supporting libraries (Boost, GLib, GTK, etc.), and a
8419 couple of additional development tools---these are the dependencies
8420 @command{guix show inkscape} lists.
8423 @c TODO: Move (gnu packages) interface to a section of its own.
8425 Last, the @code{(gnu packages)} module provides higher-level facilities
8426 to build manifests. In particular, it lets you look up packages by
8429 @deffn {Scheme Procedure} specifications->manifest @var{specs}
8430 Given @var{specs}, a list of specifications such as @code{"emacs@@25.2"}
8431 or @code{"guile:debug"}, return a manifest. Specs have the format that
8432 command-line tools such as @command{guix install} and @command{guix
8433 package} understand (@pxref{Invoking guix package}).
8435 As an example, it lets you rewrite the Git manifest that we saw earlier
8439 (specifications->manifest '("git" "git:send-email"))
8442 Notice that we do not need to worry about @code{use-modules}, importing
8443 the right set of modules, and referring to the right variables.
8444 Instead, we directly refer to packages in the same way as on the command
8445 line, which can often be more convenient.
8448 @c TODO: specifications->package, etc.
8452 @section Build Systems
8454 @cindex build system
8455 Each package definition specifies a @dfn{build system} and arguments for
8456 that build system (@pxref{Defining Packages}). This @code{build-system}
8457 field represents the build procedure of the package, as well as implicit
8458 dependencies of that build procedure.
8460 Build systems are @code{<build-system>} objects. The interface to
8461 create and manipulate them is provided by the @code{(guix build-system)}
8462 module, and actual build systems are exported by specific modules.
8464 @cindex bag (low-level package representation)
8465 Under the hood, build systems first compile package objects to
8466 @dfn{bags}. A @dfn{bag} is like a package, but with less
8467 ornamentation---in other words, a bag is a lower-level representation of
8468 a package, which includes all the inputs of that package, including some
8469 that were implicitly added by the build system. This intermediate
8470 representation is then compiled to a derivation (@pxref{Derivations}).
8471 The @code{package-with-c-toolchain} is an example of a way to change the
8472 implicit inputs that a package's build system pulls in (@pxref{package
8473 Reference, @code{package-with-c-toolchain}}).
8475 Build systems accept an optional list of @dfn{arguments}. In package
8476 definitions, these are passed @i{via} the @code{arguments} field
8477 (@pxref{Defining Packages}). They are typically keyword arguments
8478 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
8479 Guile Reference Manual}). The value of these arguments is usually
8480 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
8481 by the daemon (@pxref{Derivations}).
8483 The main build system is @code{gnu-build-system}, which implements the
8484 standard build procedure for GNU and many other packages. It
8485 is provided by the @code{(guix build-system gnu)} module.
8487 @defvr {Scheme Variable} gnu-build-system
8488 @code{gnu-build-system} represents the GNU Build System, and variants
8489 thereof (@pxref{Configuration, configuration and makefile conventions,,
8490 standards, GNU Coding Standards}).
8492 @cindex build phases
8493 In a nutshell, packages using it are configured, built, and installed with
8494 the usual @code{./configure && make && make check && make install}
8495 command sequence. In practice, a few additional steps are often needed.
8496 All these steps are split up in separate @dfn{phases}.
8497 @xref{Build Phases}, for more info on build phases and ways to customize
8500 In addition, this build system ensures that the ``standard'' environment
8501 for GNU packages is available. This includes tools such as GCC, libc,
8502 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
8503 build-system gnu)} module for a complete list). We call these the
8504 @dfn{implicit inputs} of a package, because package definitions do not
8505 have to mention them.
8507 This build system supports a number of keyword arguments, which can be
8508 passed @i{via} the @code{arguments} field of a package. Here are some
8509 of the main parameters:
8513 This argument specifies build-side code that evaluates to an alist of
8514 build phases. @xref{Build Phases}, for more information.
8516 @item #:configure-flags
8517 This is a list of flags (strings) passed to the @command{configure}
8518 script. @xref{Defining Packages}, for an example.
8521 This list of strings contains flags passed as arguments to
8522 @command{make} invocations in the @code{build}, @code{check}, and
8523 @code{install} phases.
8525 @item #:out-of-source?
8526 This Boolean, @code{#f} by default, indicates whether to run builds in a
8527 build directory separate from the source tree.
8529 When it is true, the @code{configure} phase creates a separate build
8530 directory, changes to that directory, and runs the @code{configure}
8531 script from there. This is useful for packages that require it, such as
8535 This Boolean, @code{#t} by default, indicates whether the @code{check}
8536 phase should run the package's test suite.
8539 This string, @code{"check"} by default, gives the name of the makefile
8540 target used by the @code{check} phase.
8542 @item #:parallel-build?
8543 @itemx #:parallel-tests?
8544 These Boolean values specify whether to build, respectively run the test
8545 suite, in parallel, with the @code{-j} flag of @command{make}. When
8546 they are true, @code{make} is passed @code{-j@var{n}}, where @var{n} is
8547 the number specified as the @option{--cores} option of
8548 @command{guix-daemon} or that of the @command{guix} client command
8549 (@pxref{Common Build Options, @option{--cores}}).
8551 @cindex RUNPATH, validation
8552 @item #:validate-runpath?
8553 This Boolean, @code{#t} by default, determines whether to ``validate''
8554 the @code{RUNPATH} of ELF binaries (@code{.so} shared libraries as well
8555 as executables) previously installed by the @code{install} phase.
8556 @xref{phase-validate-runpath, the @code{validate-runpath} phase}, for
8559 @item #:substitutable?
8560 This Boolean, @code{#t} by default, tells whether the package outputs
8561 should be substitutable---i.e., whether users should be able to obtain
8562 substitutes for them instead of building locally (@pxref{Substitutes}).
8564 @item #:allowed-references
8565 @itemx #:disallowed-references
8566 When true, these arguments must be a list of dependencies that must not
8567 appear among the references of the build results. If, upon build
8568 completion, some of these references are retained, the build process
8571 This is useful to ensure that a package does not erroneously keep a
8572 reference to some of it build-time inputs, in cases where doing so
8573 would, for example, unnecessarily increase its size (@pxref{Invoking
8577 Most other build systems support these keyword arguments.
8580 Other @code{<build-system>} objects are defined to support other
8581 conventions and tools used by free software packages. They inherit most
8582 of @code{gnu-build-system}, and differ mainly in the set of inputs
8583 implicitly added to the build process, and in the list of phases
8584 executed. Some of these build systems are listed below.
8586 @defvr {Scheme Variable} ant-build-system
8587 This variable is exported by @code{(guix build-system ant)}. It
8588 implements the build procedure for Java packages that can be built with
8589 @url{https://ant.apache.org/, Ant build tool}.
8591 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
8592 provided by the @code{icedtea} package to the set of inputs. Different
8593 packages can be specified with the @code{#:ant} and @code{#:jdk}
8594 parameters, respectively.
8596 When the original package does not provide a suitable Ant build file,
8597 the parameter @code{#:jar-name} can be used to generate a minimal Ant
8598 build file @file{build.xml} with tasks to build the specified jar
8599 archive. In this case the parameter @code{#:source-dir} can be used to
8600 specify the source sub-directory, defaulting to ``src''.
8602 The @code{#:main-class} parameter can be used with the minimal ant
8603 buildfile to specify the main class of the resulting jar. This makes the
8604 jar file executable. The @code{#:test-include} parameter can be used to
8605 specify the list of junit tests to run. It defaults to
8606 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
8607 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
8608 because abstract classes cannot be run as tests.
8610 The parameter @code{#:build-target} can be used to specify the Ant task
8611 that should be run during the @code{build} phase. By default the
8612 ``jar'' task will be run.
8616 @defvr {Scheme Variable} android-ndk-build-system
8617 @cindex Android distribution
8618 @cindex Android NDK build system
8619 This variable is exported by @code{(guix build-system android-ndk)}. It
8620 implements a build procedure for Android NDK (native development kit)
8621 packages using a Guix-specific build process.
8623 The build system assumes that packages install their public interface
8624 (header) files to the subdirectory @file{include} of the @code{out} output and
8625 their libraries to the subdirectory @file{lib} the @code{out} output.
8627 It's also assumed that the union of all the dependencies of a package
8628 has no conflicting files.
8630 For the time being, cross-compilation is not supported - so right now
8631 the libraries and header files are assumed to be host tools.
8635 @defvr {Scheme Variable} asdf-build-system/source
8636 @defvrx {Scheme Variable} asdf-build-system/sbcl
8637 @defvrx {Scheme Variable} asdf-build-system/ecl
8639 These variables, exported by @code{(guix build-system asdf)}, implement
8640 build procedures for Common Lisp packages using
8641 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
8642 definition facility for Common Lisp programs and libraries.
8644 The @code{asdf-build-system/source} system installs the packages in
8645 source form, and can be loaded using any common lisp implementation, via
8646 ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
8647 systems in the format which a particular implementation understands.
8648 These build systems can also be used to produce executable programs, or
8649 lisp images which contain a set of packages pre-loaded.
8651 The build system uses naming conventions. For binary packages, the
8652 package name should be prefixed with the lisp implementation, such as
8653 @code{sbcl-} for @code{asdf-build-system/sbcl}.
8655 Additionally, the corresponding source package should be labeled using
8656 the same convention as python packages (see @ref{Python Modules}), using
8657 the @code{cl-} prefix.
8659 In order to create executable programs and images, the build-side
8660 procedures @code{build-program} and @code{build-image} can be used.
8661 They should be called in a build phase after the
8662 @code{create-asdf-configuration} phase, so that the system which was
8663 just built can be used within the resulting image. @code{build-program}
8664 requires a list of Common Lisp expressions to be passed as the
8665 @code{#:entry-program} argument.
8667 By default, all the @file{.asd} files present in the sources are read to
8668 find system definitions. The @code{#:asd-files} parameter can be used
8669 to specify the list of @file{.asd} files to read. Furthermore, if the
8670 package defines a system for its tests in a separate file, it will be
8671 loaded before the tests are run if it is specified by the
8672 @code{#:test-asd-file} parameter. If it is not set, the files
8673 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
8674 and @code{test.asd} will be tried if they exist.
8676 If for some reason the package must be named in a different way than the
8677 naming conventions suggest, or if several systems must be compiled, the
8678 @code{#:asd-systems} parameter can be used to specify the list of system
8683 @defvr {Scheme Variable} cargo-build-system
8684 @cindex Rust programming language
8685 @cindex Cargo (Rust build system)
8686 This variable is exported by @code{(guix build-system cargo)}. It
8687 supports builds of packages using Cargo, the build tool of the
8688 @uref{https://www.rust-lang.org, Rust programming language}.
8690 It adds @code{rustc} and @code{cargo} to the set of inputs.
8691 A different Rust package can be specified with the @code{#:rust} parameter.
8693 Regular cargo dependencies should be added to the package definition similarly
8694 to other packages; those needed only at build time to native-inputs, others to
8695 inputs. If you need to add source-only crates then you should add them to via
8696 the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
8697 spec can be a package or a source definition. Note that the spec must
8698 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
8699 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
8700 should be added to the package definition via the
8701 @code{#:cargo-development-inputs} parameter.
8703 In its @code{configure} phase, this build system will make any source inputs
8704 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
8705 parameters available to cargo. It will also remove an included
8706 @code{Cargo.lock} file to be recreated by @code{cargo} during the
8707 @code{build} phase. The @code{package} phase will run @code{cargo package}
8708 to create a source crate for future use. The @code{install} phase installs
8709 the binaries defined by the crate. Unless @code{install-source? #f} is
8710 defined it will also install a source crate repository of itself and unpacked
8711 sources, to ease in future hacking on rust packages.
8714 @defvr {Scheme Variable} chicken-build-system
8715 This variable is exported by @code{(guix build-system chicken)}. It
8716 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
8717 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
8718 gets compiled by a C compiler, in this case GCC.
8720 This build system adds @code{chicken} to the package inputs, as well as
8721 the packages of @code{gnu-build-system}.
8723 The build system can't (yet) deduce the egg's name automatically, so just like
8724 with @code{go-build-system} and its @code{#:import-path}, you should define
8725 @code{#:egg-name} in the package's @code{arguments} field.
8727 For example, if you are packaging the @code{srfi-1} egg:
8730 (arguments '(#:egg-name "srfi-1"))
8733 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
8734 because CHICKEN doesn't embed absolute references in compiled eggs.
8735 Test dependencies should go to @code{native-inputs}, as usual.
8738 @defvr {Scheme Variable} copy-build-system
8739 This variable is exported by @code{(guix build-system copy)}. It
8740 supports builds of simple packages that don't require much compiling,
8741 mostly just moving files around.
8743 It adds much of the @code{gnu-build-system} packages to the set of
8744 inputs. Because of this, the @code{copy-build-system} does not require
8745 all the boilerplate code often needed for the
8746 @code{trivial-build-system}.
8748 To further simplify the file installation process, an
8749 @code{#:install-plan} argument is exposed to let the packager specify
8750 which files go where. The install plan is a list of @code{(@var{source}
8751 @var{target} [@var{filters}])}. @var{filters} are optional.
8754 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
8756 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
8757 @item Otherwise install @var{source} as @var{target}.
8760 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
8761 the trailing slash of @var{target} is implied with the same meaning
8764 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
8765 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
8766 @code{#:exclude-regexp}, only select files are installed depending on
8767 the filters. Each filters is specified by a list of strings.
8769 @item With @code{#:include}, install all the files which the path suffix matches
8770 at least one of the elements in the given list.
8771 @item With @code{#:include-regexp}, install all the files which the
8772 subpaths match at least one of the regular expressions in the given
8774 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
8775 are the complement of their inclusion counterpart. Without @code{#:include} flags,
8776 install all files but those matching the exclusion filters.
8777 If both inclusions and exclusions are specified, the exclusions are done
8778 on top of the inclusions.
8781 In all cases, the paths relative to @var{source} are preserved within
8788 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
8789 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
8790 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
8791 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
8792 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
8793 @file{share/my-app/sub/file}.
8794 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
8795 @file{share/my-app/file}.
8800 @cindex Clojure (programming language)
8801 @cindex simple Clojure build system
8802 @defvr {Scheme Variable} clojure-build-system
8803 This variable is exported by @code{(guix build-system clojure)}. It implements
8804 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
8805 using plain old @code{compile} in Clojure. Cross-compilation is not supported
8808 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
8809 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
8810 @code{#:zip} parameters, respectively.
8812 A list of source directories, test directories and jar names can be specified
8813 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
8814 parameters, respectively. Compile directory and main class can be specified
8815 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
8816 Other parameters are documented below.
8818 This build system is an extension of @code{ant-build-system}, but with the
8819 following phases changed:
8824 This phase calls @code{compile} in Clojure to compile source files and runs
8825 @command{jar} to create jars from both source files and compiled files
8826 according to the include list and exclude list specified in
8827 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
8828 has priority over the include list. These lists consist of symbols
8829 representing Clojure libraries or the special keyword @code{#:all} representing
8830 all Clojure libraries found under the source directories. The parameter
8831 @code{#:omit-source?} decides if source should be included into the jars.
8834 This phase runs tests according to the include list and exclude list specified
8835 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
8836 meanings are analogous to that of @code{#:aot-include} and
8837 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
8838 stands for all Clojure libraries found under the test directories. The
8839 parameter @code{#:tests?} decides if tests should be run.
8842 This phase installs all jars built previously.
8845 Apart from the above, this build system also contains an additional phase:
8850 This phase installs all top-level files with base name matching
8851 @code{%doc-regex}. A different regex can be specified with the
8852 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
8853 directories specified in @code{#:doc-dirs} are installed as well.
8857 @defvr {Scheme Variable} cmake-build-system
8858 This variable is exported by @code{(guix build-system cmake)}. It
8859 implements the build procedure for packages using the
8860 @url{https://www.cmake.org, CMake build tool}.
8862 It automatically adds the @code{cmake} package to the set of inputs.
8863 Which package is used can be specified with the @code{#:cmake}
8866 The @code{#:configure-flags} parameter is taken as a list of flags
8867 passed to the @command{cmake} command. The @code{#:build-type}
8868 parameter specifies in abstract terms the flags passed to the compiler;
8869 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
8870 debugging information''), which roughly means that code is compiled with
8871 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
8874 @defvr {Scheme Variable} dune-build-system
8875 This variable is exported by @code{(guix build-system dune)}. It
8876 supports builds of packages using @uref{https://dune.build/, Dune}, a build
8877 tool for the OCaml programming language. It is implemented as an extension
8878 of the @code{ocaml-build-system} which is described below. As such, the
8879 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
8882 It automatically adds the @code{dune} package to the set of inputs.
8883 Which package is used can be specified with the @code{#:dune}
8886 There is no @code{configure} phase because dune packages typically don't
8887 need to be configured. The @code{#:build-flags} parameter is taken as a
8888 list of flags passed to the @code{dune} command during the build.
8890 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
8891 command instead of the more recent @code{dune} command while building
8892 a package. Its default value is @code{#f}.
8894 The @code{#:package} parameter can be passed to specify a package name, which
8895 is useful when a package contains multiple packages and you want to build
8896 only one of them. This is equivalent to passing the @code{-p} argument to
8901 @defvr {Scheme variable} elm-build-system
8902 This variable is exported by @code{(guix build-system elm)}. It implements a
8903 build procedure for @url{https://elm-lang.org, Elm} packages similar to
8906 The build system adds an Elm compiler package to the set of inputs. The
8907 default compiler package (currently @code{elm-sans-reactor}) can be overridden
8908 using the @code{#:elm} argument. Additionally, Elm packages needed by the
8909 build system itself are added as implicit inputs if they are not already
8910 present: to suppress this behavior, use the
8911 @code{#:implicit-elm-package-inputs?} argument, which is primarily useful for
8914 The @code{"dependencies"} and @code{"test-dependencies"} in an Elm package's
8915 @file{elm.json} file correspond to @code{propagated-inputs} and @code{inputs},
8918 Elm requires a particular structure for package names: @pxref{Elm Packages}
8919 for more details, including utilities provided by @code{(guix build-system
8922 There are currently a few noteworthy limitations to @code{elm-build-system}:
8926 The build system is focused on @dfn{packages} in the Elm sense of the word:
8927 Elm @dfn{projects} which declare @code{@{ "type": "package" @}} in their
8928 @file{elm.json} files. Using @code{elm-build-system} to build Elm
8929 @dfn{applications} (which declare @code{@{ "type": "application" @}}) is
8930 possible, but requires ad-hoc modifications to the build phases. For
8931 examples, see the definitions of the @code{elm-todomvc} example application and
8932 the @code{elm} package itself (because the front-end for the
8933 @samp{elm reactor} command is an Elm application).
8936 Elm supports multiple versions of a package coexisting simultaneously under
8937 @env{ELM_HOME}, but this does not yet work well with @code{elm-build-system}.
8938 This limitation primarily affects Elm applications, because they specify
8939 exact versions for their dependencies, whereas Elm packages specify supported
8940 version ranges. As a workaround, the example applications mentioned above use
8941 the @code{patch-application-dependencies} procedure provided by
8942 @code{(guix build elm-build-system)} to rewrite their @file{elm.json} files to
8943 refer to the package versions actually present in the build environment.
8944 Alternatively, Guix package transformations (@pxref{Defining Package
8945 Variants}) could be used to rewrite an application's entire dependency graph.
8948 We are not yet able to run tests for Elm projects because neither
8949 @url{https://github.com/mpizenberg/elm-test-rs, @command{elm-test-rs}} nor the
8950 Node.js-based @url{https://github.com/rtfeldman/node-test-runner,
8951 @command{elm-test}} runner has been packaged for Guix yet.
8955 @defvr {Scheme Variable} go-build-system
8956 This variable is exported by @code{(guix build-system go)}. It
8957 implements a build procedure for Go packages using the standard
8958 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
8959 Go build mechanisms}.
8961 The user is expected to provide a value for the key @code{#:import-path}
8962 and, in some cases, @code{#:unpack-path}. The
8963 @url{https://golang.org/doc/code.html#ImportPaths, import path}
8964 corresponds to the file system path expected by the package's build
8965 scripts and any referring packages, and provides a unique way to
8966 refer to a Go package. It is typically based on a combination of the
8967 package source code's remote URI and file system hierarchy structure. In
8968 some cases, you will need to unpack the package's source code to a
8969 different directory structure than the one indicated by the import path,
8970 and @code{#:unpack-path} should be used in such cases.
8972 Packages that provide Go libraries should install their source code into
8973 the built output. The key @code{#:install-source?}, which defaults to
8974 @code{#t}, controls whether or not the source code is installed. It can
8975 be set to @code{#f} for packages that only provide executable files.
8977 Packages can be cross-built, and if a specific architecture or operating
8978 system is desired then the keywords @code{#:goarch} and @code{#:goos}
8979 can be used to force the package to be built for that architecture and
8980 operating system. The combinations known to Go can be found
8981 @url{"https://golang.org/doc/install/source#environment", in their
8985 @defvr {Scheme Variable} glib-or-gtk-build-system
8986 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
8987 is intended for use with packages making use of GLib or GTK+.
8989 This build system adds the following two phases to the ones defined by
8990 @code{gnu-build-system}:
8993 @item glib-or-gtk-wrap
8994 The phase @code{glib-or-gtk-wrap} ensures that programs in
8995 @file{bin/} are able to find GLib ``schemas'' and
8996 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
8997 modules}. This is achieved by wrapping the programs in launch scripts
8998 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
8999 environment variables.
9001 It is possible to exclude specific package outputs from that wrapping
9002 process by listing their names in the
9003 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
9004 when an output is known not to contain any GLib or GTK+ binaries, and
9005 where wrapping would gratuitously add a dependency of that output on
9008 @item glib-or-gtk-compile-schemas
9009 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
9010 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
9011 GSettings schemas} of GLib are compiled. Compilation is performed by the
9012 @command{glib-compile-schemas} program. It is provided by the package
9013 @code{glib:bin} which is automatically imported by the build system.
9014 The @code{glib} package providing @command{glib-compile-schemas} can be
9015 specified with the @code{#:glib} parameter.
9018 Both phases are executed after the @code{install} phase.
9021 @defvr {Scheme Variable} guile-build-system
9022 This build system is for Guile packages that consist exclusively of Scheme
9023 code and that are so lean that they don't even have a makefile, let alone a
9024 @file{configure} script. It compiles Scheme code using @command{guild
9025 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
9026 installs the @file{.scm} and @file{.go} files in the right place. It also
9027 installs documentation.
9029 This build system supports cross-compilation by using the
9030 @option{--target} option of @samp{guild compile}.
9032 Packages built with @code{guile-build-system} must provide a Guile package in
9033 their @code{native-inputs} field.
9036 @defvr {Scheme Variable} julia-build-system
9037 This variable is exported by @code{(guix build-system julia)}. It
9038 implements the build procedure used by @uref{https://julialang.org/,
9039 julia} packages, which essentially is similar to running @samp{julia -e
9040 'using Pkg; Pkg.add(package)'} in an environment where
9041 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
9042 Tests are run by calling @code{/test/runtests.jl}.
9044 The Julia package name and uuid is read from the file
9045 @file{Project.toml}. These values can be overridden by passing the
9046 argument @code{#:julia-package-name} (which must be correctly
9047 capitalized) or @code{#:julia-package-uuid}.
9049 Julia packages usually manage their binary dependencies via
9050 @code{JLLWrappers.jl}, a Julia package that creates a module (named
9051 after the wrapped library followed by @code{_jll.jl}.
9053 To add the binary path @code{_jll.jl} packages, you need to patch the
9054 files under @file{src/wrappers/}, replacing the call to the macro
9055 @code{JLLWrappers.@@generate_wrapper_header}, adding as a second
9056 argument containing the store path the binary.
9058 As an example, in the MbedTLS Julia package, we add a build phase
9059 (@pxref{Build Phases}) to insert the absolute file name of the wrapped
9063 (add-after 'unpack 'override-binary-path
9064 (lambda* (#:key inputs #:allow-other-keys)
9065 (for-each (lambda (wrapper)
9066 (substitute* wrapper
9067 (("generate_wrapper_header.*")
9069 "generate_wrapper_header(\"MbedTLS\", \""
9070 (assoc-ref inputs "mbedtls-apache") "\")\n"))))
9071 ;; There's a Julia file for each platform, override them all.
9072 (find-files "src/wrappers/" "\\.jl$"))))
9075 Some older packages that aren't using @file{Project.toml} yet, will
9076 require this file to be created, too. It is internally done if the
9077 arguments @code{#:julia-package-name} and @code{#:julia-package-uuid}
9081 @defvr {Scheme Variable} maven-build-system
9082 This variable is exported by @code{(guix build-system maven)}. It implements
9083 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
9084 is a dependency and lifecycle management tool for Java. A user of Maven
9085 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
9086 When Maven does not have one of the dependencies or plugins in its repository,
9087 it will download them and use them to build the package.
9089 The maven build system ensures that maven will not try to download any
9090 dependency by running in offline mode. Maven will fail if a dependency is
9091 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
9092 modified to specify the version of dependencies and plugins that match the
9093 versions available in the guix build environment. Dependencies and plugins
9094 must be installed in the fake maven repository at @file{lib/m2}, and are
9095 symlinked into a proper repository before maven is run. Maven is instructed
9096 to use that repository for the build and installs built artifacts there.
9097 Changed files are copied to the @file{lib/m2} directory of the package output.
9099 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
9100 or let the build system use the default @file{pom.xml} file in the sources.
9102 In case you need to specify a dependency's version manually, you can use the
9103 @code{#:local-packages} argument. It takes an association list where the key
9104 is the groupId of the package and its value is an association list where the
9105 key is the artifactId of the package and its value is the version you want to
9106 override in the @file{pom.xml}.
9108 Some packages use dependencies or plugins that are not useful at runtime nor
9109 at build time in Guix. You can alter the @file{pom.xml} file to remove them
9110 using the @code{#:exclude} argument. Its value is an association list where
9111 the key is the groupId of the plugin or dependency you want to remove, and
9112 the value is a list of artifactId you want to remove.
9114 You can override the default @code{jdk} and @code{maven} packages with the
9115 corresponding argument, @code{#:jdk} and @code{#:maven}.
9117 The @code{#:maven-plugins} argument is a list of maven plugins used during
9118 the build, with the same format as the @code{inputs} fields of the package
9119 declaration. Its default value is @code{(default-maven-plugins)} which is
9123 @defvr {Scheme Variable} minetest-mod-build-system
9124 This variable is exported by @code{(guix build-system minetest)}. It
9125 implements a build procedure for @uref{https://www.minetest.net, Minetest}
9126 mods, which consists of copying Lua code, images and other resources to
9127 the location Minetest searches for mods. The build system also minimises
9128 PNG images and verifies that Minetest can load the mod without errors.
9131 @defvr {Scheme Variable} minify-build-system
9132 This variable is exported by @code{(guix build-system minify)}. It
9133 implements a minification procedure for simple JavaScript packages.
9135 It adds @code{uglify-js} to the set of inputs and uses it to compress
9136 all JavaScript files in the @file{src} directory. A different minifier
9137 package can be specified with the @code{#:uglify-js} parameter, but it
9138 is expected that the package writes the minified code to the standard
9141 When the input JavaScript files are not all located in the @file{src}
9142 directory, the parameter @code{#:javascript-files} can be used to
9143 specify a list of file names to feed to the minifier.
9146 @defvr {Scheme Variable} ocaml-build-system
9147 This variable is exported by @code{(guix build-system ocaml)}. It implements
9148 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
9149 of choosing the correct set of commands to run for each package. OCaml
9150 packages can expect many different commands to be run. This build system will
9153 When the package has a @file{setup.ml} file present at the top-level, it will
9154 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
9155 @code{ocaml setup.ml -install}. The build system will assume that this file
9156 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
9157 care of setting the prefix and enabling tests if they are not disabled. You
9158 can pass configure and build flags with the @code{#:configure-flags} and
9159 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
9160 set of flags used to enable tests. The @code{#:use-make?} key can be used to
9161 bypass this system in the build and install phases.
9163 When the package has a @file{configure} file, it is assumed that it is a
9164 hand-made configure script that requires a different argument format than
9165 in the @code{gnu-build-system}. You can add more flags with the
9166 @code{#:configure-flags} key.
9168 When the package has a @file{Makefile} file (or @code{#:use-make?} is
9169 @code{#t}), it will be used and more flags can be passed to the build and
9170 install phases with the @code{#:make-flags} key.
9172 Finally, some packages do not have these files and use a somewhat standard
9173 location for its build system. In that case, the build system will run
9174 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
9175 providing the path to the required findlib module. Additional flags can
9176 be passed via the @code{#:build-flags} key. Install is taken care of by
9177 @command{opam-installer}. In this case, the @code{opam} package must
9178 be added to the @code{native-inputs} field of the package definition.
9180 Note that most OCaml packages assume they will be installed in the same
9181 directory as OCaml, which is not what we want in guix. In particular, they
9182 will install @file{.so} files in their module's directory, which is usually
9183 fine because it is in the OCaml compiler directory. In guix though, these
9184 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
9185 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
9186 @file{.so} libraries should be installed.
9189 @defvr {Scheme Variable} python-build-system
9190 This variable is exported by @code{(guix build-system python)}. It
9191 implements the more or less standard build procedure used by Python
9192 packages, which consists in running @code{python setup.py build} and
9193 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
9195 For packages that install stand-alone Python programs under @code{bin/},
9196 it takes care of wrapping these programs so that their
9197 @env{GUIX_PYTHONPATH} environment variable points to all the Python
9198 libraries they depend on.
9200 Which Python package is used to perform the build can be specified with
9201 the @code{#:python} parameter. This is a useful way to force a package
9202 to be built for a specific version of the Python interpreter, which
9203 might be necessary if the package is only compatible with a single
9204 interpreter version.
9206 By default guix calls @code{setup.py} under control of
9207 @code{setuptools}, much like @command{pip} does. Some packages are not
9208 compatible with setuptools (and pip), thus you can disable this by
9209 setting the @code{#:use-setuptools?} parameter to @code{#f}.
9211 If a @code{"python"} output is available, the package is installed into it
9212 instead of the default @code{"out"} output. This is useful for packages that
9213 include a Python package as only a part of the software, and thus want to
9214 combine the phases of @code{python-build-system} with another build system.
9215 Python bindings are a common usecase.
9219 @defvr {Scheme Variable} perl-build-system
9220 This variable is exported by @code{(guix build-system perl)}. It
9221 implements the standard build procedure for Perl packages, which either
9222 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
9223 followed by @code{Build} and @code{Build install}; or in running
9224 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
9225 @code{make} and @code{make install}, depending on which of
9226 @code{Build.PL} or @code{Makefile.PL} is present in the package
9227 distribution. Preference is given to the former if both @code{Build.PL}
9228 and @code{Makefile.PL} exist in the package distribution. This
9229 preference can be reversed by specifying @code{#t} for the
9230 @code{#:make-maker?} parameter.
9232 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
9233 passes flags specified by the @code{#:make-maker-flags} or
9234 @code{#:module-build-flags} parameter, respectively.
9236 Which Perl package is used can be specified with @code{#:perl}.
9239 @defvr {Scheme Variable} renpy-build-system
9240 This variable is exported by @code{(guix build-system renpy)}. It implements
9241 the more or less standard build procedure used by Ren'py games, which consists
9242 of loading @code{#:game} once, thereby creating bytecode for it.
9244 It further creates a wrapper script in @code{bin/} and a desktop entry in
9245 @code{share/applications}, both of which can be used to launch the game.
9247 Which Ren'py package is used can be specified with @code{#:renpy}.
9248 Games can also be installed in outputs other than ``out'' by using
9252 @defvr {Scheme Variable} qt-build-system
9253 This variable is exported by @code{(guix build-system qt)}. It
9254 is intended for use with applications using Qt or KDE.
9256 This build system adds the following two phases to the ones defined by
9257 @code{cmake-build-system}:
9261 The phase @code{check-setup} prepares the environment for running
9262 the checks as commonly used by Qt test programs.
9263 For now this only sets some environment variables:
9264 @code{QT_QPA_PLATFORM=offscreen},
9265 @code{DBUS_FATAL_WARNINGS=0} and
9266 @code{CTEST_OUTPUT_ON_FAILURE=1}.
9268 This phase is added before the @code{check} phase.
9269 It's a separate phase to ease adjusting if necessary.
9272 The phase @code{qt-wrap}
9273 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
9274 and output. In case some path is found, all programs in the output's
9275 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
9276 are wrapped in scripts defining the necessary environment variables.
9278 It is possible to exclude specific package outputs from that wrapping process
9279 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
9280 This is useful when an output is known not to contain any Qt binaries, and
9281 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
9284 This phase is added after the @code{install} phase.
9288 @defvr {Scheme Variable} r-build-system
9289 This variable is exported by @code{(guix build-system r)}. It
9290 implements the build procedure used by @uref{https://r-project.org, R}
9291 packages, which essentially is little more than running @samp{R CMD
9292 INSTALL --library=/gnu/store/@dots{}} in an environment where
9293 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
9294 run after installation using the R function
9295 @code{tools::testInstalledPackage}.
9298 @defvr {Scheme Variable} rakudo-build-system
9299 This variable is exported by @code{(guix build-system rakudo)}. It
9300 implements the build procedure used by @uref{https://rakudo.org/,
9301 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
9302 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
9303 installs the binaries, library files and the resources, as well as wrap
9304 the files under the @code{bin/} directory. Tests can be skipped by
9305 passing @code{#f} to the @code{tests?} parameter.
9307 Which rakudo package is used can be specified with @code{rakudo}.
9308 Which perl6-tap-harness package used for the tests can be specified with
9309 @code{#:prove6} or removed by passing @code{#f} to the
9310 @code{with-prove6?} parameter.
9311 Which perl6-zef package used for tests and installing can be specified
9312 with @code{#:zef} or removed by passing @code{#f} to the
9313 @code{with-zef?} parameter.
9316 @defvr {Scheme Variable} rebar-build-system
9317 This variable is exported by @code{(guix build-system rebar)}. It
9318 implements a build procedure around @uref{https://rebar3.org,rebar3},
9319 a build system for programs written in the Erlang language.
9321 It adds both @code{rebar3} and the @code{erlang} to the set of inputs.
9322 Different packages can be specified with the @code{#:rebar} and
9323 @code{#:erlang} parameters, respectively.
9325 This build system is based on @code{gnu-build-system}, but with the
9326 following phases changed:
9331 This phase, after unpacking the source like the @code{gnu-build-system}
9332 does, checks for a file @code{contents.tar.gz} at the top-level of the
9333 source. If this file exists, it will be unpacked, too. This eases
9334 handling of package hosted at @uref{https://hex.pm/},
9335 the Erlang and Elixir package repository.
9339 There are no @code{bootstrap} and @code{configure} phase because erlang
9340 packages typically don’t need to be configured.
9343 This phase runs @code{rebar3 compile}
9344 with the flags listed in @code{#:rebar-flags}.
9347 Unless @code{#:tests? #f} is passed,
9348 this phase runs @code{rebar3 eunit},
9349 or some other target specified with @code{#:test-target},
9350 with the flags listed in @code{#:rebar-flags},
9353 This installs the files created in the @i{default} profile, or some
9354 other profile specified with @code{#:install-profile}.
9359 @defvr {Scheme Variable} texlive-build-system
9360 This variable is exported by @code{(guix build-system texlive)}. It is
9361 used to build TeX packages in batch mode with a specified engine. The
9362 build system sets the @env{TEXINPUTS} variable to find all TeX source
9363 files in the inputs.
9365 By default it runs @code{luatex} on all files ending on @code{ins}. A
9366 different engine and format can be specified with the
9367 @code{#:tex-format} argument. Different build targets can be specified
9368 with the @code{#:build-targets} argument, which expects a list of file
9369 names. The build system adds only @code{texlive-bin} and
9370 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
9371 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
9372 and @code{#:texlive-latex-base}, respectively.
9374 The @code{#:tex-directory} parameter tells the build system where to
9375 install the built files under the texmf tree.
9378 @defvr {Scheme Variable} ruby-build-system
9379 This variable is exported by @code{(guix build-system ruby)}. It
9380 implements the RubyGems build procedure used by Ruby packages, which
9381 involves running @code{gem build} followed by @code{gem install}.
9383 The @code{source} field of a package that uses this build system
9384 typically references a gem archive, since this is the format that Ruby
9385 developers use when releasing their software. The build system unpacks
9386 the gem archive, potentially patches the source, runs the test suite,
9387 repackages the gem, and installs it. Additionally, directories and
9388 tarballs may be referenced to allow building unreleased gems from Git or
9389 a traditional source release tarball.
9391 Which Ruby package is used can be specified with the @code{#:ruby}
9392 parameter. A list of additional flags to be passed to the @command{gem}
9393 command can be specified with the @code{#:gem-flags} parameter.
9396 @defvr {Scheme Variable} waf-build-system
9397 This variable is exported by @code{(guix build-system waf)}. It
9398 implements a build procedure around the @code{waf} script. The common
9399 phases---@code{configure}, @code{build}, and @code{install}---are
9400 implemented by passing their names as arguments to the @code{waf}
9403 The @code{waf} script is executed by the Python interpreter. Which
9404 Python package is used to run the script can be specified with the
9405 @code{#:python} parameter.
9408 @defvr {Scheme Variable} scons-build-system
9409 This variable is exported by @code{(guix build-system scons)}. It
9410 implements the build procedure used by the SCons software construction
9411 tool. This build system runs @code{scons} to build the package,
9412 @code{scons test} to run tests, and then @code{scons install} to install
9415 Additional flags to be passed to @code{scons} can be specified with the
9416 @code{#:scons-flags} parameter. The default build and install targets
9417 can be overridden with @code{#:build-targets} and
9418 @code{#:install-targets} respectively. The version of Python used to
9419 run SCons can be specified by selecting the appropriate SCons package
9420 with the @code{#:scons} parameter.
9423 @defvr {Scheme Variable} haskell-build-system
9424 This variable is exported by @code{(guix build-system haskell)}. It
9425 implements the Cabal build procedure used by Haskell packages, which
9426 involves running @code{runhaskell Setup.hs configure
9427 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
9428 Instead of installing the package by running @code{runhaskell Setup.hs
9429 install}, to avoid trying to register libraries in the read-only
9430 compiler store directory, the build system uses @code{runhaskell
9431 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
9432 addition, the build system generates the package documentation by
9433 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
9434 is passed. Optional Haddock parameters can be passed with the help of
9435 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
9436 not found, the build system looks for @code{Setup.lhs} instead.
9438 Which Haskell compiler is used can be specified with the @code{#:haskell}
9439 parameter which defaults to @code{ghc}.
9442 @defvr {Scheme Variable} dub-build-system
9443 This variable is exported by @code{(guix build-system dub)}. It
9444 implements the Dub build procedure used by D packages, which
9445 involves running @code{dub build} and @code{dub run}.
9446 Installation is done by copying the files manually.
9448 Which D compiler is used can be specified with the @code{#:ldc}
9449 parameter which defaults to @code{ldc}.
9452 @anchor{emacs-build-system}
9453 @defvr {Scheme Variable} emacs-build-system
9454 This variable is exported by @code{(guix build-system emacs)}. It
9455 implements an installation procedure similar to the packaging system
9456 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9458 It first creates the @code{@code{package}-autoloads.el} file, then it
9459 byte compiles all Emacs Lisp files. Differently from the Emacs
9460 packaging system, the Info documentation files are moved to the standard
9461 documentation directory and the @file{dir} file is deleted. The Elisp
9462 package files are installed directly under @file{share/emacs/site-lisp}.
9465 @defvr {Scheme Variable} font-build-system
9466 This variable is exported by @code{(guix build-system font)}. It
9467 implements an installation procedure for font packages where upstream
9468 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
9469 need to be copied into place. It copies font files to standard
9470 locations in the output directory.
9473 @defvr {Scheme Variable} meson-build-system
9474 This variable is exported by @code{(guix build-system meson)}. It
9475 implements the build procedure for packages that use
9476 @url{https://mesonbuild.com, Meson} as their build system.
9478 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
9479 of inputs, and they can be changed with the parameters @code{#:meson}
9480 and @code{#:ninja} if needed.
9482 This build system is an extension of @code{gnu-build-system}, but with the
9483 following phases changed to some specific for Meson:
9488 The phase runs @code{meson} with the flags specified in
9489 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
9490 @code{debugoptimized} unless something else is specified in
9491 @code{#:build-type}.
9494 The phase runs @code{ninja} to build the package in parallel by default, but
9495 this can be changed with @code{#:parallel-build?}.
9498 The phase runs @samp{meson test} with a base set of options that cannot
9499 be overridden. This base set of options can be extended via the
9500 @code{#:test-options} argument, for example to select or skip a specific
9504 The phase runs @code{ninja install} and can not be changed.
9507 Apart from that, the build system also adds the following phases:
9512 This phase ensures that all binaries can find the libraries they need.
9513 It searches for required libraries in subdirectories of the package
9514 being built, and adds those to @code{RUNPATH} where needed. It also
9515 removes references to libraries left over from the build phase by
9516 @code{meson}, such as test dependencies, that aren't actually required
9517 for the program to run.
9519 @item glib-or-gtk-wrap
9520 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9521 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9523 @item glib-or-gtk-compile-schemas
9524 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9525 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9529 @defvr {Scheme Variable} linux-module-build-system
9530 @code{linux-module-build-system} allows building Linux kernel modules.
9532 @cindex build phases
9533 This build system is an extension of @code{gnu-build-system}, but with the
9534 following phases changed:
9539 This phase configures the environment so that the Linux kernel's Makefile
9540 can be used to build the external kernel module.
9543 This phase uses the Linux kernel's Makefile in order to build the external
9547 This phase uses the Linux kernel's Makefile in order to install the external
9551 It is possible and useful to specify the Linux kernel to use for building
9552 the module (in the @code{arguments} form of a package using the
9553 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
9556 @defvr {Scheme Variable} node-build-system
9557 This variable is exported by @code{(guix build-system node)}. It
9558 implements the build procedure used by @uref{https://nodejs.org,
9559 Node.js}, which implements an approximation of the @code{npm install}
9560 command, followed by an @code{npm test} command.
9562 Which Node.js package is used to interpret the @code{npm} commands can
9563 be specified with the @code{#:node} parameter which defaults to
9567 Lastly, for packages that do not need anything as sophisticated, a
9568 ``trivial'' build system is provided. It is trivial in the sense that
9569 it provides basically no support: it does not pull any implicit inputs,
9570 and does not have a notion of build phases.
9572 @defvr {Scheme Variable} trivial-build-system
9573 This variable is exported by @code{(guix build-system trivial)}.
9575 This build system requires a @code{#:builder} argument. This argument
9576 must be a Scheme expression that builds the package output(s)---as
9577 with @code{build-expression->derivation} (@pxref{Derivations,
9578 @code{build-expression->derivation}}).
9581 @defvr {Scheme Variable} channel-build-system
9582 This variable is exported by @code{(guix build-system channel)}.
9584 This build system is meant primarily for internal use. A package using
9585 this build system must have a channel specification as its @code{source}
9586 field (@pxref{Channels}); alternatively, its source can be a directory
9587 name, in which case an additional @code{#:commit} argument must be
9588 supplied to specify the commit being built (a hexadecimal string).
9590 The resulting package is a Guix instance of the given channel, similar
9591 to how @command{guix time-machine} would build it.
9595 @section Build Phases
9597 @cindex build phases, for packages
9598 Almost all package build systems implement a notion @dfn{build phases}:
9599 a sequence of actions that the build system executes, when you build the
9600 package, leading to the installed byproducts in the store. A notable
9601 exception is the ``bare-bones'' @code{trivial-build-system}
9602 (@pxref{Build Systems}).
9604 As discussed in the previous section, those build systems provide a
9605 standard list of phases. For @code{gnu-build-system}, the main build
9606 phases are the following:
9610 Define search path environment variables for all the input packages,
9611 including @env{PATH} (@pxref{Search Paths}).
9614 Unpack the source tarball, and change the current directory to the
9615 extracted source tree. If the source is actually a directory, copy it
9616 to the build tree, and enter that directory.
9618 @item patch-source-shebangs
9619 Patch shebangs encountered in source files so they refer to the right
9620 store file names. For instance, this changes @code{#!/bin/sh} to
9621 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
9624 Run the @file{configure} script with a number of default options, such
9625 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
9626 by the @code{#:configure-flags} argument.
9629 Run @code{make} with the list of flags specified with
9630 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
9631 (the default), build with @code{make -j}.
9634 Run @code{make check}, or some other target specified with
9635 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
9636 @code{#:parallel-tests?} argument is true (the default), run @code{make
9640 Run @code{make install} with the flags listed in @code{#:make-flags}.
9642 @item patch-shebangs
9643 Patch shebangs on the installed executable files.
9646 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
9647 is false), copying them to the @code{debug} output when available
9648 (@pxref{Installing Debugging Files}).
9650 @cindex RUNPATH, validation
9651 @anchor{phase-validate-runpath}
9652 @item validate-runpath
9653 Validate the @code{RUNPATH} of ELF binaries, unless
9654 @code{#:validate-runpath?} is false (@pxref{Build Systems}).
9656 This validation step consists in making sure that all the shared
9657 libraries needed by an ELF binary, which are listed as @code{DT_NEEDED}
9658 entries in its @code{PT_DYNAMIC} segment, appear in the
9659 @code{DT_RUNPATH} entry of that binary. In other words, it ensures that
9660 running or using those binaries will not result in a ``file not found''
9661 error at run time. @xref{Options, @option{-rpath},, ld, The GNU
9662 Linker}, for more information on @code{RUNPATH}.
9666 Other build systems have similar phases, with some variations. For
9667 example, @code{cmake-build-system} has same-named phases but its
9668 @code{configure} phases runs @code{cmake} instead of @code{./configure}.
9669 Others, such as @code{python-build-system}, have a wholly different list
9670 of standard phases. All this code runs on the @dfn{build side}: it is
9671 evaluated when you actually build the package, in a dedicated build
9672 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
9674 Build phases are represented as association lists or ``alists''
9675 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
9676 each key is a symbol for the name of the phase and the associated value
9677 is a procedure that accepts an arbitrary number of arguments. By
9678 convention, those procedures receive information about the build in the
9679 form of @dfn{keyword parameters}, which they can use or ignore.
9681 @vindex %standard-phases
9682 For example, here is how @code{(guix build gnu-build-system)} defines
9683 @code{%standard-phases}, the variable holding its alist of build
9684 phases@footnote{We present a simplified view of those build phases, but
9685 do take a look at @code{(guix build gnu-build-system)} to see all the
9689 ;; The build phases of 'gnu-build-system'.
9691 (define* (unpack #:key source #:allow-other-keys)
9692 ;; Extract the source tarball.
9693 (invoke "tar" "xvf" source))
9695 (define* (configure #:key outputs #:allow-other-keys)
9696 ;; Run the 'configure' script. Install to output "out".
9697 (let ((out (assoc-ref outputs "out")))
9698 (invoke "./configure"
9699 (string-append "--prefix=" out))))
9701 (define* (build #:allow-other-keys)
9705 (define* (check #:key (test-target "check") (tests? #true)
9707 ;; Run the test suite.
9709 (invoke "make" test-target)
9710 (display "test suite not run\n")))
9712 (define* (install #:allow-other-keys)
9713 ;; Install files to the prefix 'configure' specified.
9714 (invoke "make" "install"))
9716 (define %standard-phases
9717 ;; The list of standard phases (quite a few are omitted
9718 ;; for brevity). Each element is a symbol/procedure pair.
9719 (list (cons 'unpack unpack)
9720 (cons 'configure configure)
9723 (cons 'install install)))
9726 This shows how @code{%standard-phases} is defined as a list of
9727 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
9728 Manual}). The first pair associates the @code{unpack} procedure with
9729 the @code{unpack} symbol---a name; the second pair defines the
9730 @code{configure} phase similarly, and so on. When building a package
9731 that uses @code{gnu-build-system} with its default list of phases, those
9732 phases are executed sequentially. You can see the name of each phase
9733 started and completed in the build log of packages that you build.
9735 Let's now look at the procedures themselves. Each one is defined with
9736 @code{define*}: @code{#:key} lists keyword parameters the procedure
9737 accepts, possibly with a default value, and @code{#:allow-other-keys}
9738 specifies that other keyword parameters are ignored (@pxref{Optional
9739 Arguments,,, guile, GNU Guile Reference Manual}).
9741 The @code{unpack} procedure honors the @code{source} parameter, which
9742 the build system uses to pass the file name of the source tarball (or
9743 version control checkout), and it ignores other parameters. The
9744 @code{configure} phase only cares about the @code{outputs} parameter, an
9745 alist mapping package output names to their store file name
9746 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
9747 for @code{out}, the default output, and passes it to
9748 @command{./configure} as the installation prefix, meaning that
9749 @command{make install} will eventually copy all the files in that
9750 directory (@pxref{Configuration, configuration and makefile
9751 conventions,, standards, GNU Coding Standards}). @code{build} and
9752 @code{install} ignore all their arguments. @code{check} honors the
9753 @code{test-target} argument, which specifies the name of the Makefile
9754 target to run tests; it prints a message and skips tests when
9755 @code{tests?} is false.
9757 @cindex build phases, customizing
9758 The list of phases used for a particular package can be changed with the
9759 @code{#:phases} parameter of the build system. Changing the set of
9760 build phases boils down to building a new alist of phases based on the
9761 @code{%standard-phases} alist described above. This can be done with
9762 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
9763 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
9764 more convenient to do so with @code{modify-phases} (@pxref{Build
9765 Utilities, @code{modify-phases}}).
9767 Here is an example of a package definition that removes the
9768 @code{configure} phase of @code{%standard-phases} and inserts a new
9769 phase before the @code{build} phase, called
9770 @code{set-prefix-in-makefile}:
9773 (define-public example
9776 ;; other fields omitted
9777 (build-system gnu-build-system)
9779 '(#:phases (modify-phases %standard-phases
9781 (add-before 'build 'set-prefix-in-makefile
9782 (lambda* (#:key outputs #:allow-other-keys)
9783 ;; Modify the makefile so that its
9784 ;; 'PREFIX' variable points to "out".
9785 (let ((out (assoc-ref outputs "out")))
9786 (substitute* "Makefile"
9788 (string-append "PREFIX = "
9792 The new phase that is inserted is written as an anonymous procedure,
9793 introduced with @code{lambda*}; it honors the @code{outputs} parameter
9794 we have seen before. @xref{Build Utilities}, for more about the helpers
9795 used by this phase, and for more examples of @code{modify-phases}.
9797 @cindex code staging
9798 @cindex staging, of code
9799 Keep in mind that build phases are code evaluated at the time the
9800 package is actually built. This explains why the whole
9801 @code{modify-phases} expression above is quoted (it comes after the
9802 @code{'} or apostrophe): it is @dfn{staged} for later execution.
9803 @xref{G-Expressions}, for an explanation of code staging and the
9804 @dfn{code strata} involved.
9806 @node Build Utilities
9807 @section Build Utilities
9809 As soon as you start writing non-trivial package definitions
9810 (@pxref{Defining Packages}) or other build actions
9811 (@pxref{G-Expressions}), you will likely start looking for helpers for
9812 ``shell-like'' actions---creating directories, copying and deleting
9813 files recursively, manipulating build phases, and so on. The
9814 @code{(guix build utils)} module provides such utility procedures.
9816 Most build systems load @code{(guix build utils)} (@pxref{Build
9817 Systems}). Thus, when writing custom build phases for your package
9818 definitions, you can usually assume those procedures are in scope.
9820 When writing G-expressions, you can import @code{(guix build utils)} on
9821 the ``build side'' using @code{with-imported-modules} and then put it in
9822 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
9823 guile, GNU Guile Reference Manual}):
9826 (with-imported-modules '((guix build utils)) ;import it
9827 (computed-file "empty-tree"
9830 (use-modules (guix build utils))
9832 ;; Happily use its 'mkdir-p' procedure.
9833 (mkdir-p (string-append #$output "/a/b/c")))))
9836 The remainder of this section is the reference for most of the utility
9837 procedures provided by @code{(guix build utils)}.
9839 @c TODO Document what's missing.
9841 @subsection Dealing with Store File Names
9843 This section documents procedures that deal with store file names.
9845 @deffn {Scheme Procedure} %store-directory
9846 Return the directory name of the store.
9849 @deffn {Scheme Procedure} store-file-name? @var{file}
9850 Return true if @var{file} is in the store.
9853 @deffn {Scheme Procedure} strip-store-file-name @var{file}
9854 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
9855 The result is typically a @code{"@var{package}-@var{version}"} string.
9858 @deffn {Scheme Procedure} package-name->name+version @var{name}
9859 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
9860 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
9861 unavailable, @var{name} and @code{#f} are returned. The first hyphen
9862 followed by a digit is considered to introduce the version part.
9865 @subsection File Types
9867 The procedures below deal with files and file types.
9869 @deffn {Scheme Procedure} directory-exists? @var{dir}
9870 Return @code{#t} if @var{dir} exists and is a directory.
9873 @deffn {Scheme Procedure} executable-file? @var{file}
9874 Return @code{#t} if @var{file} exists and is executable.
9877 @deffn {Scheme Procedure} symbolic-link? @var{file}
9878 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
9881 @deffn {Scheme Procedure} elf-file? @var{file}
9882 @deffnx {Scheme Procedure} ar-file? @var{file}
9883 @deffnx {Scheme Procedure} gzip-file? @var{file}
9884 Return @code{#t} if @var{file} is, respectively, an ELF file, an
9885 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
9888 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
9889 If @var{file} is a gzip file, reset its embedded timestamp (as with
9890 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
9891 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
9894 @subsection File Manipulation
9896 The following procedures and macros help create, modify, and delete
9897 files. They provide functionality comparable to common shell utilities
9898 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
9899 @command{sed}. They complement Guile's extensive, but low-level, file
9900 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
9902 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
9903 Run @var{body} with @var{directory} as the process's current directory.
9905 Essentially, this macro changes the current directory to @var{directory}
9906 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
9907 guile, GNU Guile Reference Manual}). It changes back to the initial
9908 directory when the dynamic extent of @var{body} is left, be it @i{via}
9909 normal procedure return or @i{via} a non-local exit such as an
9913 @deffn {Scheme Procedure} mkdir-p @var{dir}
9914 Create directory @var{dir} and all its ancestors.
9917 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
9918 Create @var{directory} if it does not exist and copy @var{file} in there
9919 under the same name.
9922 @deffn {Scheme Procedure} make-file-writable @var{file}
9923 Make @var{file} writable for its owner.
9926 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
9927 [#:log (current-output-port)] [#:follow-symlinks? #f] @
9928 [#:copy-file copy-file] [#:keep-mtime? #f] [#:keep-permissions? #t]
9929 Copy @var{source} directory to @var{destination}. Follow symlinks if
9930 @var{follow-symlinks?} is true; otherwise, just preserve them. Call
9931 @var{copy-file} to copy regular files. When @var{keep-mtime?} is true,
9932 keep the modification time of the files in @var{source} on those of
9933 @var{destination}. When @var{keep-permissions?} is true, preserve file
9934 permissions. Write verbose output to the @var{log} port.
9937 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
9938 [#:follow-mounts? #f]
9939 Delete @var{dir} recursively, like @command{rm -rf}, without following
9940 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
9941 is true. Report but ignore errors.
9944 @deffn {Scheme Syntax} substitute* @var{file} @
9945 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
9946 Substitute @var{regexp} in @var{file} by the string returned by
9947 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
9948 the corresponding positional regexp sub-expression. For example:
9954 (("foo([a-z]+)bar(.*)$" all letters end)
9955 (string-append "baz" letters end)))
9958 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
9959 by @code{good morning}. Anytime a line of @var{file} matches the second
9960 regexp, @code{all} is bound to the complete match, @code{letters} is bound
9961 to the first sub-expression, and @code{end} is bound to the last one.
9963 When one of the @var{match-var} is @code{_}, no variable is bound to the
9964 corresponding match substring.
9966 Alternatively, @var{file} may be a list of file names, in which case
9967 they are all subject to the substitutions.
9969 Be careful about using @code{$} to match the end of a line; by itself it
9970 won't match the terminating newline of a line.
9973 @subsection File Search
9975 @cindex file, searching
9976 This section documents procedures to search and filter files.
9978 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
9979 Return a predicate that returns true when passed a file name whose base
9980 name matches @var{regexp}.
9983 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
9984 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
9985 Return the lexicographically sorted list of files under @var{dir} for
9986 which @var{pred} returns true. @var{pred} is passed two arguments: the
9987 absolute file name, and its stat buffer; the default predicate always
9988 returns true. @var{pred} can also be a regular expression, in which
9989 case it is equivalent to @code{(file-name-predicate @var{pred})}.
9990 @var{stat} is used to obtain file information; using @code{lstat} means
9991 that symlinks are not followed. If @var{directories?} is true, then
9992 directories will also be included. If @var{fail-on-error?} is true,
9993 raise an exception upon error.
9996 Here are a few examples where we assume that the current directory is
9997 the root of the Guix source tree:
10000 ;; List all the regular files in the current directory.
10002 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
10004 ;; List all the .scm files under gnu/services.
10005 (find-files "gnu/services" "\\.scm$")
10006 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
10008 ;; List ar files in the current directory.
10009 (find-files "." (lambda (file stat) (ar-file? file)))
10010 @result{} ("./libformat.a" "./libstore.a" @dots{})
10013 @deffn {Scheme Procedure} which @var{program}
10014 Return the complete file name for @var{program} as found in
10015 @code{$PATH}, or @code{#f} if @var{program} could not be found.
10018 @deffn {Scheme Procedure} search-input-file @var{inputs} @var{name}
10019 @deffnx {Scheme Procedure} search-input-directory @var{inputs} @var{name}
10020 Return the complete file name for @var{name} as found in @var{inputs};
10021 @code{search-input-file} searches for a regular file and
10022 @code{search-input-directory} searches for a directory. If @var{name}
10023 could not be found, an exception is raised.
10025 Here, @var{inputs} must be an association list like @code{inputs} and
10026 @code{native-inputs} as available to build phases (@pxref{Build
10030 Here is a (simplified) example of how @code{search-input-file} is used
10031 in a build phase of the @code{wireguard-tools} package:
10034 (add-after 'install 'wrap-wg-quick
10035 (lambda* (#:key inputs outputs #:allow-other-keys)
10036 (let ((coreutils (string-append (assoc-ref inputs "coreutils")
10038 (wrap-program (search-input-file outputs "bin/wg-quick")
10039 #:sh (search-input-file inputs "bin/bash")
10040 `("PATH" ":" prefix ,(list coreutils))))))
10043 @subsection Program Invocation
10045 @cindex program invocation, from Scheme
10046 @cindex invoking programs, from Scheme
10047 You'll find handy procedures to spawn processes in this module,
10048 essentially convenient wrappers around Guile's @code{system*}
10049 (@pxref{Processes, @code{system*},, guile, GNU Guile Reference Manual}).
10051 @deffn {Scheme Procedure} invoke @var{program} @var{args}@dots{}
10052 Invoke @var{program} with the given @var{args}. Raise an
10053 @code{&invoke-error} exception if the exit code is non-zero; otherwise
10056 The advantage compared to @code{system*} is that you do not need to
10057 check the return value. This reduces boilerplate in shell-script-like
10058 snippets for instance in package build phases.
10061 @deffn {Scheme Procedure} invoke-error? @var{c}
10062 Return true if @var{c} is an @code{&invoke-error} condition.
10065 @deffn {Scheme Procedure} invoke-error-program @var{c}
10066 @deffnx {Scheme Procedure} invoke-error-arguments @var{c}
10067 @deffnx {Scheme Procedure} invoke-error-exit-status @var{c}
10068 @deffnx {Scheme Procedure} invoke-error-term-signal @var{c}
10069 @deffnx {Scheme Procedure} invoke-error-stop-signal @var{c}
10070 Access specific fields of @var{c}, an @code{&invoke-error} condition.
10073 @deffn {Scheme Procedure} report-invoke-error @var{c} [@var{port}]
10074 Report to @var{port} (by default the current error port) about @var{c},
10075 an @code{&invoke-error} condition, in a human-friendly way.
10077 Typical usage would look like this:
10080 (use-modules (srfi srfi-34) ;for 'guard'
10081 (guix build utils))
10083 (guard (c ((invoke-error? c)
10084 (report-invoke-error c)))
10085 (invoke "date" "--imaginary-option"))
10087 @print{} command "date" "--imaginary-option" failed with status 1
10091 @deffn {Scheme Procedure} invoke/quiet @var{program} @var{args}@dots{}
10092 Invoke @var{program} with @var{args} and capture @var{program}'s
10093 standard output and standard error. If @var{program} succeeds, print
10094 nothing and return the unspecified value; otherwise, raise a
10095 @code{&message} error condition that includes the status code and the
10096 output of @var{program}.
10101 (use-modules (srfi srfi-34) ;for 'guard'
10102 (srfi srfi-35) ;for 'message-condition?'
10103 (guix build utils))
10105 (guard (c ((message-condition? c)
10106 (display (condition-message c))))
10107 (invoke/quiet "date") ;all is fine
10108 (invoke/quiet "date" "--imaginary-option"))
10110 @print{} 'date --imaginary-option' exited with status 1; output follows:
10112 date: unrecognized option '--imaginary-option'
10113 Try 'date --help' for more information.
10117 @subsection Build Phases
10119 @cindex build phases
10120 The @code{(guix build utils)} also contains tools to manipulate build
10121 phases as used by build systems (@pxref{Build Systems}). Build phases
10122 are represented as association lists or ``alists'' (@pxref{Association
10123 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
10124 naming the phase and the associated value is a procedure (@pxref{Build
10127 Guile core and the @code{(srfi srfi-1)} module both provide tools to
10128 manipulate alists. The @code{(guix build utils)} module complements
10129 those with tools written with build phases in mind.
10131 @cindex build phases, modifying
10132 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
10133 Modify @var{phases} sequentially as per each @var{clause}, which may
10134 have one of the following forms:
10137 (delete @var{old-phase-name})
10138 (replace @var{old-phase-name} @var{new-phase})
10139 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10140 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10143 Where every @var{phase-name} above is an expression evaluating to a
10144 symbol, and @var{new-phase} an expression evaluating to a procedure.
10147 The example below is taken from the definition of the @code{grep}
10148 package. It adds a phase to run after the @code{install} phase, called
10149 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
10150 is for anonymous procedures) that takes a @code{#:outputs} keyword
10151 argument and ignores extra keyword arguments (@pxref{Optional
10152 Arguments,,, guile, GNU Guile Reference Manual}, for more on
10153 @code{lambda*} and optional and keyword arguments.) The phase uses
10154 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
10155 scripts so that they refer to @code{grep} by its absolute file name:
10158 (modify-phases %standard-phases
10159 (add-after 'install 'fix-egrep-and-fgrep
10160 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
10161 ;; absolute file name instead of searching for it in $PATH.
10162 (lambda* (#:key outputs #:allow-other-keys)
10163 (let* ((out (assoc-ref outputs "out"))
10164 (bin (string-append out "/bin")))
10165 (substitute* (list (string-append bin "/egrep")
10166 (string-append bin "/fgrep"))
10168 (string-append "exec " bin "/grep")))))))
10171 In the example below, phases are modified in two ways: the standard
10172 @code{configure} phase is deleted, presumably because the package does
10173 not have a @file{configure} script or anything similar, and the default
10174 @code{install} phase is replaced by one that manually copies the
10175 executable files to be installed:
10178 (modify-phases %standard-phases
10179 (delete 'configure) ;no 'configure' script
10181 (lambda* (#:key outputs #:allow-other-keys)
10182 ;; The package's Makefile doesn't provide an "install"
10183 ;; rule so do it by ourselves.
10184 (let ((bin (string-append (assoc-ref outputs "out")
10186 (install-file "footswitch" bin)
10187 (install-file "scythe" bin)))))
10190 @c TODO: Add more examples.
10192 @subsection Wrappers
10194 @cindex program wrappers
10195 @cindex wrapping programs
10196 It is not unusual for a command to require certain environment variables
10197 to be set for proper functioning, typically search paths (@pxref{Search
10198 Paths}). Failing to do that, the command might fail to find files or
10199 other commands it relies on, or it might pick the ``wrong''
10200 ones---depending on the environment in which it runs. Examples include:
10204 a shell script that assumes all the commands it uses are in @env{PATH};
10207 a Guile program that assumes all its modules are in @env{GUILE_LOAD_PATH}
10208 and @env{GUILE_LOAD_COMPILED_PATH};
10211 a Qt application that expects to find certain plugins in
10212 @env{QT_PLUGIN_PATH}.
10215 For a package writer, the goal is to make sure commands always work the
10216 same rather than depend on some external settings. One way to achieve
10217 that is to @dfn{wrap} commands in a thin script that sets those
10218 environment variables, thereby ensuring that those run-time dependencies
10219 are always found. The wrapper would be used to set @env{PATH},
10220 @env{GUILE_LOAD_PATH}, or @env{QT_PLUGIN_PATH} in the examples above.
10222 To ease that task, the @code{(guix build utils)} module provides a
10223 couple of helpers to wrap commands.
10225 @deffn {Scheme Procedure} wrap-program @var{program} @
10226 [#:sh @var{sh}] [#:rest @var{variables}]
10227 Make a wrapper for @var{program}. @var{variables} should look like this:
10230 '(@var{variable} @var{delimiter} @var{position} @var{list-of-directories})
10233 where @var{delimiter} is optional. @code{:} will be used if
10234 @var{delimiter} is not given.
10236 For example, this call:
10239 (wrap-program "foo"
10240 '("PATH" ":" = ("/gnu/.../bar/bin"))
10241 '("CERT_PATH" suffix ("/gnu/.../baz/certs"
10245 will copy @file{foo} to @file{.foo-real} and create the file @file{foo}
10246 with the following contents:
10249 #!location/of/bin/bash
10250 export PATH="/gnu/.../bar/bin"
10251 export CERT_PATH="$CERT_PATH$@{CERT_PATH:+:@}/gnu/.../baz/certs:/qux/certs"
10252 exec -a $0 location/of/.foo-real "$@@"
10255 If @var{program} has previously been wrapped by @code{wrap-program}, the
10256 wrapper is extended with definitions for @var{variables}. If it is not,
10257 @var{sh} will be used as the interpreter.
10260 @deffn {Scheme Procedure} wrap-script @var{program} @
10261 [#:guile @var{guile}] [#:rest @var{variables}]
10262 Wrap the script @var{program} such that @var{variables} are set first.
10263 The format of @var{variables} is the same as in the @code{wrap-program}
10264 procedure. This procedure differs from @code{wrap-program} in that it
10265 does not create a separate shell script. Instead, @var{program} is
10266 modified directly by prepending a Guile script, which is interpreted as
10267 a comment in the script's language.
10269 Special encoding comments as supported by Python are recreated on the
10272 Note that this procedure can only be used once per file as Guile scripts are
10277 @section Search Paths
10279 @cindex search path
10280 Many programs and libraries look for input data in a @dfn{search path},
10281 a list of directories: shells like Bash look for executables in the
10282 command search path, a C compiler looks for @file{.h} files in its
10283 header search path, the Python interpreter looks for @file{.py}
10284 files in its search path, the spell checker has a search path for
10285 dictionaries, and so on.
10287 Search paths can usually be defined or overridden @i{via} environment
10288 variables (@pxref{Environment Variables,,, libc, The GNU C Library
10289 Reference Manual}). For example, the search paths mentioned above can
10290 be changed by defining the @env{PATH}, @env{C_INCLUDE_PATH},
10291 @env{PYTHONPATH} (or @env{GUIX_PYTHONPATH}), and @env{DICPATH}
10292 environment variables---you know, all these something-PATH variables
10293 that you need to get right or things ``won't be found''.
10295 You may have noticed from the command line that Guix ``knows'' which
10296 search path environment variables should be defined, and how. When you
10297 install packages in your default profile, the file
10298 @file{~/.guix-profile/etc/profile} is created, which you can ``source''
10299 from the shell to set those variables. Likewise, if you ask
10300 @command{guix shell} to create an environment containing Python and
10301 NumPy, a Python library, and if you pass it the @option{--search-paths}
10302 option, it will tell you about @env{PATH} and @env{GUIX_PYTHONPATH}
10303 (@pxref{Invoking guix shell}):
10306 $ guix shell python python-numpy --pure --search-paths
10307 export PATH="/gnu/store/@dots{}-profile/bin"
10308 export GUIX_PYTHONPATH="/gnu/store/@dots{}-profile/lib/python3.9/site-packages"
10311 When you omit @option{--search-paths}, it defines these environment
10312 variables right away, such that Python can readily find NumPy:
10315 $ guix shell python python-numpy -- python3
10316 Python 3.9.6 (default, Jan 1 1970, 00:00:01)
10317 [GCC 10.3.0] on linux
10318 Type "help", "copyright", "credits" or "license" for more information.
10320 >>> numpy.version.version
10324 For this to work, the definition of the @code{python} package
10325 @emph{declares} the search path it cares about and its associated
10326 environment variable, @env{GUIX_PYTHONPATH}. It looks like this:
10332 ;; some fields omitted...
10333 (native-search-paths
10334 (list (search-path-specification
10335 (variable "GUIX_PYTHONPATH")
10336 (files (list "lib/python/3.9/site-packages"))))))
10339 What this @code{native-search-paths} field says is that, when the
10340 @code{python} package is used, the @env{GUIX_PYTHONPATH} environment
10341 variable must be defined to include all the
10342 @file{lib/python/3.9/site-packages} sub-directories encountered in its
10343 environment. (The @code{native-} bit means that, if we are in a
10344 cross-compilation environment, only native inputs may be added to the
10345 search path; @pxref{package Reference, @code{search-paths}}.)
10346 In the NumPy example above, the profile where
10347 @code{python} appears contains exactly one such sub-directory, and
10348 @env{GUIX_PYTHONPATH} is set to that. When there are several
10349 @file{lib/python/3.9/site-packages}---this is the case in package build
10350 environments---they are all added to @env{GUIX_PYTHONPATH}, separated by
10354 Notice that @env{GUIX_PYTHONPATH} is specified as part of the definition
10355 of the @code{python} package, and @emph{not} as part of that of
10356 @code{python-numpy}. This is because this environment variable
10357 ``belongs'' to Python, not NumPy: Python actually reads the value of
10358 that variable and honors it.
10360 Corollary: if you create a profile that does not contain @code{python},
10361 @code{GUIX_PYTHONPATH} will @emph{not} be defined, even if it contains
10362 packages that provide @file{.py} files:
10365 $ guix shell python-numpy --search-paths --pure
10366 export PATH="/gnu/store/@dots{}-profile/bin"
10369 This makes a lot of sense if we look at this profile in isolation: no
10370 software in this profile would read @env{GUIX_PYTHONPATH}.
10373 Of course, there are many variations on that theme: some packages honor
10374 more than one search path, some use separators other than colon, some
10375 accumulate several directories in their search path, and so on. A more
10376 complex example is the search path of libxml2: the value of the
10377 @env{XML_CATALOG_FILES} environment variable is space-separated, it must
10378 contain a list of @file{catalog.xml} files (not directories), which are
10379 to be found in @file{xml} sub-directories---nothing less. The search
10380 path specification looks like this:
10385 ;; some fields omitted
10386 (native-search-paths
10387 (list (search-path-specification
10388 (variable "XML_CATALOG_FILES")
10391 (file-pattern "^catalog\\.xml$")
10392 (file-type 'regular)))))
10395 Worry not, search path specifications are usually not this tricky.
10397 The @code{(guix search-paths)} module defines the data type of search
10398 path specifications and a number of helper procedures. Below is the
10399 reference of search path specifications.
10401 @deftp {Data Type} search-path-specification
10402 The data type for search path specifications.
10405 @item @code{variable}
10406 The name of the environment variable for this search path (a string).
10409 The list of sub-directories (strings) that should be added to the search
10412 @item @code{separator} (default: @code{":"})
10413 The string used to separate search path components.
10415 As a special case, a @code{separator} value of @code{#f} specifies a
10416 ``single-component search path''---in other words, a search path that
10417 cannot contain more than one element. This is useful in some cases,
10418 such as the @code{SSL_CERT_DIR} variable (honored by OpenSSL, cURL, and
10419 a few other packages) or the @code{ASPELL_DICT_DIR} variable (honored by
10420 the GNU Aspell spell checker), both of which must point to a single
10423 @item @code{file-type} (default: @code{'directory})
10424 The type of file being matched---@code{'directory} or @code{'regular},
10425 though it can be any symbol returned by @code{stat:type} (@pxref{File
10426 System, @code{stat},, guile, GNU Guile Reference Manual}).
10428 In the libxml2 example above, we would match regular files; in the
10429 Python example, we would match directories.
10431 @item @code{file-pattern} (default: @code{#f})
10432 This must be either @code{#f} or a regular expression specifying
10433 files to be matched @emph{within} the sub-directories specified by the
10434 @code{files} field.
10436 Again, the libxml2 example shows a situation where this is needed.
10440 Some search paths are not tied by a single package but to many packages.
10441 To reduce duplications, some of them are pre-defined in @code{(guix
10444 @defvr {Scheme Variable} $SSL_CERT_DIR
10445 @defvrx {Scheme Variable} $SSL_CERT_FILE
10446 These two search paths indicate where X.509 certificates can be found
10447 (@pxref{X.509 Certificates}).
10450 These pre-defined search paths can be used as in the following example:
10455 ;; some fields omitted ...
10456 (native-search-paths (list $SSL_CERT_DIR $SSL_CERT_FILE)))
10459 How do you turn search path specifications on one hand and a bunch of
10460 directories on the other hand in a set of environment variable
10461 definitions? That's the job of @code{evaluate-search-paths}.
10463 @deffn {Scheme Procedure} evaluate-search-paths @var{search-paths} @
10464 @var{directories} [@var{getenv}]
10465 Evaluate @var{search-paths}, a list of search-path specifications, for
10466 @var{directories}, a list of directory names, and return a list of
10467 specification/value pairs. Use @var{getenv} to determine the current
10468 settings and report only settings not already effective.
10471 The @code{(guix profiles)} provides a higher-level helper procedure,
10472 @code{load-profile}, that sets the environment variables of a profile.
10478 @cindex store items
10479 @cindex store paths
10481 Conceptually, the @dfn{store} is the place where derivations that have
10482 been built successfully are stored---by default, @file{/gnu/store}.
10483 Sub-directories in the store are referred to as @dfn{store items} or
10484 sometimes @dfn{store paths}. The store has an associated database that
10485 contains information such as the store paths referred to by each store
10486 path, and the list of @emph{valid} store items---results of successful
10487 builds. This database resides in @file{@var{localstatedir}/guix/db},
10488 where @var{localstatedir} is the state directory specified @i{via}
10489 @option{--localstatedir} at configure time, usually @file{/var}.
10491 The store is @emph{always} accessed by the daemon on behalf of its clients
10492 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
10493 connect to the daemon over a Unix-domain socket, send requests to it,
10494 and read the result---these are remote procedure calls, or RPCs.
10497 Users must @emph{never} modify files under @file{/gnu/store} directly.
10498 This would lead to inconsistencies and break the immutability
10499 assumptions of Guix's functional model (@pxref{Introduction}).
10501 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
10502 how to check the integrity of the store and attempt recovery from
10503 accidental modifications.
10506 The @code{(guix store)} module provides procedures to connect to the
10507 daemon, and to perform RPCs. These are described below. By default,
10508 @code{open-connection}, and thus all the @command{guix} commands,
10509 connect to the local daemon or to the URI specified by the
10510 @env{GUIX_DAEMON_SOCKET} environment variable.
10512 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
10513 When set, the value of this variable should be a file name or a URI
10514 designating the daemon endpoint. When it is a file name, it denotes a
10515 Unix-domain socket to connect to. In addition to file names, the
10516 supported URI schemes are:
10521 These are for Unix-domain sockets.
10522 @code{file:///var/guix/daemon-socket/socket} is equivalent to
10523 @file{/var/guix/daemon-socket/socket}.
10526 @cindex daemon, remote access
10527 @cindex remote access to the daemon
10528 @cindex daemon, cluster setup
10529 @cindex clusters, daemon setup
10530 These URIs denote connections over TCP/IP, without encryption nor
10531 authentication of the remote host. The URI must specify the host name
10532 and optionally a port number (by default port 44146 is used):
10535 guix://master.guix.example.org:1234
10538 This setup is suitable on local networks, such as clusters, where only
10539 trusted nodes may connect to the build daemon at
10540 @code{master.guix.example.org}.
10542 The @option{--listen} option of @command{guix-daemon} can be used to
10543 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
10544 @option{--listen}}).
10547 @cindex SSH access to build daemons
10548 These URIs allow you to connect to a remote daemon over SSH@. This
10549 feature requires Guile-SSH (@pxref{Requirements}) and a working
10550 @command{guile} binary in @env{PATH} on the destination machine. It
10551 supports public key and GSSAPI authentication. A typical URL might look
10555 ssh://charlie@@guix.example.org:22
10558 As for @command{guix copy}, the usual OpenSSH client configuration files
10559 are honored (@pxref{Invoking guix copy}).
10562 Additional URI schemes may be supported in the future.
10564 @c XXX: Remove this note when the protocol incurs fewer round trips
10565 @c and when (guix derivations) no longer relies on file system access.
10567 The ability to connect to remote build daemons is considered
10568 experimental as of @value{VERSION}. Please get in touch with us to
10569 share any problems or suggestions you may have (@pxref{Contributing}).
10573 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
10574 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
10575 @var{reserve-space?} is true, instruct it to reserve a little bit of
10576 extra space on the file system so that the garbage collector can still
10577 operate should the disk become full. Return a server object.
10579 @var{file} defaults to @code{%default-socket-path}, which is the normal
10580 location given the options that were passed to @command{configure}.
10583 @deffn {Scheme Procedure} close-connection @var{server}
10584 Close the connection to @var{server}.
10587 @defvr {Scheme Variable} current-build-output-port
10588 This variable is bound to a SRFI-39 parameter, which refers to the port
10589 where build and error logs sent by the daemon should be written.
10592 Procedures that make RPCs all take a server object as their first
10595 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
10596 @cindex invalid store items
10597 Return @code{#t} when @var{path} designates a valid store item and
10598 @code{#f} otherwise (an invalid item may exist on disk but still be
10599 invalid, for instance because it is the result of an aborted or failed
10602 A @code{&store-protocol-error} condition is raised if @var{path} is not
10603 prefixed by the store directory (@file{/gnu/store}).
10606 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
10607 Add @var{text} under file @var{name} in the store, and return its store
10608 path. @var{references} is the list of store paths referred to by the
10609 resulting store path.
10612 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
10614 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
10615 file names, or derivation/output pairs, using the specified
10616 @var{mode}---@code{(build-mode normal)} by default.
10619 Note that the @code{(guix monads)} module provides a monad as well as
10620 monadic versions of the above procedures, with the goal of making it
10621 more convenient to work with code that accesses the store (@pxref{The
10625 @i{This section is currently incomplete.}
10628 @section Derivations
10630 @cindex derivations
10631 Low-level build actions and the environment in which they are performed
10632 are represented by @dfn{derivations}. A derivation contains the
10633 following pieces of information:
10637 The outputs of the derivation---derivations produce at least one file or
10638 directory in the store, but may produce more.
10641 @cindex build-time dependencies
10642 @cindex dependencies, build-time
10643 The inputs of the derivations---i.e., its build-time dependencies---which may
10644 be other derivations or plain files in the store (patches, build scripts,
10648 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
10651 The file name of a build script in the store, along with the arguments
10655 A list of environment variables to be defined.
10659 @cindex derivation path
10660 Derivations allow clients of the daemon to communicate build actions to
10661 the store. They exist in two forms: as an in-memory representation,
10662 both on the client- and daemon-side, and as files in the store whose
10663 name end in @file{.drv}---these files are referred to as @dfn{derivation
10664 paths}. Derivations paths can be passed to the @code{build-derivations}
10665 procedure to perform the build actions they prescribe (@pxref{The
10668 @cindex fixed-output derivations
10669 Operations such as file downloads and version-control checkouts for
10670 which the expected content hash is known in advance are modeled as
10671 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
10672 of a fixed-output derivation are independent of its inputs---e.g., a
10673 source code download produces the same result regardless of the download
10674 method and tools being used.
10677 @cindex run-time dependencies
10678 @cindex dependencies, run-time
10679 The outputs of derivations---i.e., the build results---have a set of
10680 @dfn{references}, as reported by the @code{references} RPC or the
10681 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
10682 are the set of run-time dependencies of the build results. References are a
10683 subset of the inputs of the derivation; this subset is automatically computed
10684 by the build daemon by scanning all the files in the outputs.
10686 The @code{(guix derivations)} module provides a representation of
10687 derivations as Scheme objects, along with procedures to create and
10688 otherwise manipulate derivations. The lowest-level primitive to create
10689 a derivation is the @code{derivation} procedure:
10691 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
10692 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10693 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
10694 [#:system (%current-system)] [#:references-graphs #f] @
10695 [#:allowed-references #f] [#:disallowed-references #f] @
10696 [#:leaked-env-vars #f] [#:local-build? #f] @
10697 [#:substitutable? #t] [#:properties '()]
10698 Build a derivation with the given arguments, and return the resulting
10699 @code{<derivation>} object.
10701 When @var{hash} and @var{hash-algo} are given, a
10702 @dfn{fixed-output derivation} is created---i.e., one whose result is
10703 known in advance, such as a file download. If, in addition,
10704 @var{recursive?} is true, then that fixed output may be an executable
10705 file or a directory and @var{hash} must be the hash of an archive
10706 containing this output.
10708 When @var{references-graphs} is true, it must be a list of file
10709 name/store path pairs. In that case, the reference graph of each store
10710 path is exported in the build environment in the corresponding file, in
10711 a simple text format.
10713 When @var{allowed-references} is true, it must be a list of store items
10714 or outputs that the derivation's output may refer to. Likewise,
10715 @var{disallowed-references}, if true, must be a list of things the
10716 outputs may @emph{not} refer to.
10718 When @var{leaked-env-vars} is true, it must be a list of strings
10719 denoting environment variables that are allowed to ``leak'' from the
10720 daemon's environment to the build environment. This is only applicable
10721 to fixed-output derivations---i.e., when @var{hash} is true. The main
10722 use is to allow variables such as @code{http_proxy} to be passed to
10723 derivations that download files.
10725 When @var{local-build?} is true, declare that the derivation is not a
10726 good candidate for offloading and should rather be built locally
10727 (@pxref{Daemon Offload Setup}). This is the case for small derivations
10728 where the costs of data transfers would outweigh the benefits.
10730 When @var{substitutable?} is false, declare that substitutes of the
10731 derivation's output should not be used (@pxref{Substitutes}). This is
10732 useful, for instance, when building packages that capture details of the
10733 host CPU instruction set.
10735 @var{properties} must be an association list describing ``properties'' of the
10736 derivation. It is kept as-is, uninterpreted, in the derivation.
10740 Here's an example with a shell script as its builder, assuming
10741 @var{store} is an open connection to the daemon, and @var{bash} points
10742 to a Bash executable in the store:
10745 (use-modules (guix utils)
10747 (guix derivations))
10749 (let ((builder ; add the Bash script to the store
10750 (add-text-to-store store "my-builder.sh"
10751 "echo hello world > $out\n" '())))
10752 (derivation store "foo"
10753 bash `("-e" ,builder)
10754 #:inputs `((,bash) (,builder))
10755 #:env-vars '(("HOME" . "/homeless"))))
10756 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
10759 As can be guessed, this primitive is cumbersome to use directly. A
10760 better approach is to write build scripts in Scheme, of course! The
10761 best course of action for that is to write the build code as a
10762 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
10763 information, @pxref{G-Expressions}.
10765 Once upon a time, @code{gexp->derivation} did not exist and constructing
10766 derivations with build code written in Scheme was achieved with
10767 @code{build-expression->derivation}, documented below. This procedure
10768 is now deprecated in favor of the much nicer @code{gexp->derivation}.
10770 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
10771 @var{name} @var{exp} @
10772 [#:system (%current-system)] [#:inputs '()] @
10773 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10774 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
10775 [#:references-graphs #f] [#:allowed-references #f] @
10776 [#:disallowed-references #f] @
10777 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
10778 Return a derivation that executes Scheme expression @var{exp} as a
10779 builder for derivation @var{name}. @var{inputs} must be a list of
10780 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
10781 @code{"out"} is assumed. @var{modules} is a list of names of Guile
10782 modules from the current search path to be copied in the store,
10783 compiled, and made available in the load path during the execution of
10784 @var{exp}---e.g., @code{((guix build utils) (guix build
10785 gnu-build-system))}.
10787 @var{exp} is evaluated in an environment where @code{%outputs} is bound
10788 to a list of output/path pairs, and where @code{%build-inputs} is bound
10789 to a list of string/output-path pairs made from @var{inputs}.
10790 Optionally, @var{env-vars} is a list of string pairs specifying the name
10791 and value of environment variables visible to the builder. The builder
10792 terminates by passing the result of @var{exp} to @code{exit}; thus, when
10793 @var{exp} returns @code{#f}, the build is considered to have failed.
10795 @var{exp} is built using @var{guile-for-build} (a derivation). When
10796 @var{guile-for-build} is omitted or is @code{#f}, the value of the
10797 @code{%guile-for-build} fluid is used instead.
10799 See the @code{derivation} procedure for the meaning of
10800 @var{references-graphs}, @var{allowed-references},
10801 @var{disallowed-references}, @var{local-build?}, and
10802 @var{substitutable?}.
10806 Here's an example of a single-output derivation that creates a directory
10807 containing one file:
10810 (let ((builder '(let ((out (assoc-ref %outputs "out")))
10811 (mkdir out) ; create /gnu/store/@dots{}-goo
10812 (call-with-output-file (string-append out "/test")
10814 (display '(hello guix) p))))))
10815 (build-expression->derivation store "goo" builder))
10817 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
10821 @node The Store Monad
10822 @section The Store Monad
10826 The procedures that operate on the store described in the previous
10827 sections all take an open connection to the build daemon as their first
10828 argument. Although the underlying model is functional, they either have
10829 side effects or depend on the current state of the store.
10831 The former is inconvenient: the connection to the build daemon has to be
10832 carried around in all those functions, making it impossible to compose
10833 functions that do not take that parameter with functions that do. The
10834 latter can be problematic: since store operations have side effects
10835 and/or depend on external state, they have to be properly sequenced.
10837 @cindex monadic values
10838 @cindex monadic functions
10839 This is where the @code{(guix monads)} module comes in. This module
10840 provides a framework for working with @dfn{monads}, and a particularly
10841 useful monad for our uses, the @dfn{store monad}. Monads are a
10842 construct that allows two things: associating ``context'' with values
10843 (in our case, the context is the store), and building sequences of
10844 computations (here computations include accesses to the store). Values
10845 in a monad---values that carry this additional context---are called
10846 @dfn{monadic values}; procedures that return such values are called
10847 @dfn{monadic procedures}.
10849 Consider this ``normal'' procedure:
10852 (define (sh-symlink store)
10853 ;; Return a derivation that symlinks the 'bash' executable.
10854 (let* ((drv (package-derivation store bash))
10855 (out (derivation->output-path drv))
10856 (sh (string-append out "/bin/bash")))
10857 (build-expression->derivation store "sh"
10858 `(symlink ,sh %output))))
10861 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
10862 as a monadic function:
10865 (define (sh-symlink)
10866 ;; Same, but return a monadic value.
10867 (mlet %store-monad ((drv (package->derivation bash)))
10868 (gexp->derivation "sh"
10869 #~(symlink (string-append #$drv "/bin/bash")
10873 There are several things to note in the second version: the @code{store}
10874 parameter is now implicit and is ``threaded'' in the calls to the
10875 @code{package->derivation} and @code{gexp->derivation} monadic
10876 procedures, and the monadic value returned by @code{package->derivation}
10877 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
10879 As it turns out, the call to @code{package->derivation} can even be
10880 omitted since it will take place implicitly, as we will see later
10881 (@pxref{G-Expressions}):
10884 (define (sh-symlink)
10885 (gexp->derivation "sh"
10886 #~(symlink (string-append #$bash "/bin/bash")
10891 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
10892 @c for the funny quote.
10893 Calling the monadic @code{sh-symlink} has no effect. As someone once
10894 said, ``you exit a monad like you exit a building on fire: by running''.
10895 So, to exit the monad and get the desired effect, one must use
10896 @code{run-with-store}:
10899 (run-with-store (open-connection) (sh-symlink))
10900 @result{} /gnu/store/...-sh-symlink
10903 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
10904 new ``commands'' to make it easier to deal with monadic procedures:
10905 @code{run-in-store}, and @code{enter-store-monad} (@pxref{Using Guix
10906 Interactively}). The former is used
10907 to ``run'' a single monadic value through the store:
10910 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
10911 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10914 The latter enters a recursive REPL, where all the return values are
10915 automatically run through the store:
10918 scheme@@(guile-user)> ,enter-store-monad
10919 store-monad@@(guile-user) [1]> (package->derivation hello)
10920 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10921 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
10922 $3 = "/gnu/store/@dots{}-foo"
10923 store-monad@@(guile-user) [1]> ,q
10924 scheme@@(guile-user)>
10928 Note that non-monadic values cannot be returned in the
10929 @code{store-monad} REPL.
10931 Other meta-commands are available at the REPL, such as @code{,build} to
10932 build a file-like object (@pxref{Using Guix Interactively}).
10934 The main syntactic forms to deal with monads in general are provided by
10935 the @code{(guix monads)} module and are described below.
10937 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
10938 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
10942 @deffn {Scheme Syntax} return @var{val}
10943 Return a monadic value that encapsulates @var{val}.
10946 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
10947 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
10948 procedures @var{mproc}@dots{}@footnote{This operation is commonly
10949 referred to as ``bind'', but that name denotes an unrelated procedure in
10950 Guile. Thus we use this somewhat cryptic symbol inherited from the
10951 Haskell language.}. There can be one @var{mproc} or several of them, as
10956 (with-monad %state-monad
10958 (lambda (x) (return (+ 1 x)))
10959 (lambda (x) (return (* 2 x)))))
10963 @result{} some-state
10967 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
10969 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
10971 Bind the variables @var{var} to the monadic values @var{mval} in
10972 @var{body}, which is a sequence of expressions. As with the bind
10973 operator, this can be thought of as ``unpacking'' the raw, non-monadic
10974 value ``contained'' in @var{mval} and making @var{var} refer to that
10975 raw, non-monadic value within the scope of the @var{body}. The form
10976 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
10977 @var{val}, as per @code{let}. The binding operations occur in sequence
10978 from left to right. The last expression of @var{body} must be a monadic
10979 expression, and its result will become the result of the @code{mlet} or
10980 @code{mlet*} when run in the @var{monad}.
10982 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
10983 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
10986 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
10987 Bind @var{mexp} and the following monadic expressions in sequence,
10988 returning the result of the last expression. Every expression in the
10989 sequence must be a monadic expression.
10991 This is akin to @code{mlet}, except that the return values of the
10992 monadic expressions are ignored. In that sense, it is analogous to
10993 @code{begin}, but applied to monadic expressions.
10996 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
10997 When @var{condition} is true, evaluate the sequence of monadic
10998 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
10999 @var{condition} is false, return @code{*unspecified*} in the current
11000 monad. Every expression in the sequence must be a monadic expression.
11003 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
11004 When @var{condition} is false, evaluate the sequence of monadic
11005 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
11006 @var{condition} is true, return @code{*unspecified*} in the current
11007 monad. Every expression in the sequence must be a monadic expression.
11010 @cindex state monad
11011 The @code{(guix monads)} module provides the @dfn{state monad}, which
11012 allows an additional value---the state---to be @emph{threaded} through
11013 monadic procedure calls.
11015 @defvr {Scheme Variable} %state-monad
11016 The state monad. Procedures in the state monad can access and change
11017 the state that is threaded.
11019 Consider the example below. The @code{square} procedure returns a value
11020 in the state monad. It returns the square of its argument, but also
11021 increments the current state value:
11025 (mlet %state-monad ((count (current-state)))
11026 (mbegin %state-monad
11027 (set-current-state (+ 1 count))
11028 (return (* x x)))))
11030 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
11035 When ``run'' through @code{%state-monad}, we obtain that additional state
11036 value, which is the number of @code{square} calls.
11039 @deffn {Monadic Procedure} current-state
11040 Return the current state as a monadic value.
11043 @deffn {Monadic Procedure} set-current-state @var{value}
11044 Set the current state to @var{value} and return the previous state as a
11048 @deffn {Monadic Procedure} state-push @var{value}
11049 Push @var{value} to the current state, which is assumed to be a list,
11050 and return the previous state as a monadic value.
11053 @deffn {Monadic Procedure} state-pop
11054 Pop a value from the current state and return it as a monadic value.
11055 The state is assumed to be a list.
11058 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
11059 Run monadic value @var{mval} starting with @var{state} as the initial
11060 state. Return two values: the resulting value, and the resulting state.
11063 The main interface to the store monad, provided by the @code{(guix
11064 store)} module, is as follows.
11066 @defvr {Scheme Variable} %store-monad
11067 The store monad---an alias for @code{%state-monad}.
11069 Values in the store monad encapsulate accesses to the store. When its
11070 effect is needed, a value of the store monad must be ``evaluated'' by
11071 passing it to the @code{run-with-store} procedure (see below).
11074 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
11075 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
11076 open store connection.
11079 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
11080 Return as a monadic value the absolute file name in the store of the file
11081 containing @var{text}, a string. @var{references} is a list of store items that the
11082 resulting text file refers to; it defaults to the empty list.
11085 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
11086 Return as a monadic value the absolute file name in the store of the file
11087 containing @var{data}, a bytevector. @var{references} is a list of store
11088 items that the resulting binary file refers to; it defaults to the empty list.
11091 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
11092 [#:recursive? #t] [#:select? (const #t)]
11093 Return the name of @var{file} once interned in the store. Use
11094 @var{name} as its store name, or the basename of @var{file} if
11095 @var{name} is omitted.
11097 When @var{recursive?} is true, the contents of @var{file} are added
11098 recursively; if @var{file} designates a flat file and @var{recursive?}
11099 is true, its contents are added, and its permission bits are kept.
11101 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11102 @var{stat})} for each directory entry, where @var{file} is the entry's
11103 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11104 entries for which @var{select?} does not return true.
11106 The example below adds a file to the store, under two different names:
11109 (run-with-store (open-connection)
11110 (mlet %store-monad ((a (interned-file "README"))
11111 (b (interned-file "README" "LEGU-MIN")))
11112 (return (list a b))))
11114 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
11119 The @code{(guix packages)} module exports the following package-related
11120 monadic procedures:
11122 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
11123 [#:system (%current-system)] [#:target #f] @
11125 Return as a monadic
11126 value in the absolute file name of @var{file} within the @var{output}
11127 directory of @var{package}. When @var{file} is omitted, return the name
11128 of the @var{output} directory of @var{package}. When @var{target} is
11129 true, use it as a cross-compilation target triplet.
11131 Note that this procedure does @emph{not} build @var{package}. Thus, the
11132 result might or might not designate an existing file. We recommend not
11133 using this procedure unless you know what you are doing.
11136 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
11137 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
11138 @var{target} [@var{system}]
11139 Monadic version of @code{package-derivation} and
11140 @code{package-cross-derivation} (@pxref{Defining Packages}).
11144 @node G-Expressions
11145 @section G-Expressions
11147 @cindex G-expression
11148 @cindex build code quoting
11149 So we have ``derivations'', which represent a sequence of build actions
11150 to be performed to produce an item in the store (@pxref{Derivations}).
11151 These build actions are performed when asking the daemon to actually
11152 build the derivations; they are run by the daemon in a container
11153 (@pxref{Invoking guix-daemon}).
11155 @cindex code staging
11156 @cindex staging, of code
11157 @cindex strata of code
11158 It should come as no surprise that we like to write these build actions
11159 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
11160 code@footnote{The term @dfn{stratum} in this context was coined by
11161 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
11162 Kiselyov, who has written insightful
11163 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
11164 on this topic}, refers to this kind of code generation as
11165 @dfn{staging}.}: the ``host code''---code that defines packages, talks
11166 to the daemon, etc.---and the ``build code''---code that actually
11167 performs build actions, such as making directories, invoking
11168 @command{make}, and so on (@pxref{Build Phases}).
11170 To describe a derivation and its build actions, one typically needs to
11171 embed build code inside host code. It boils down to manipulating build
11172 code as data, and the homoiconicity of Scheme---code has a direct
11173 representation as data---comes in handy for that. But we need more than
11174 the normal @code{quasiquote} mechanism in Scheme to construct build
11177 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
11178 S-expressions adapted to build expressions. G-expressions, or
11179 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
11180 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
11181 @code{#$}, and @code{#$@@}), which are comparable to
11182 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
11183 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
11184 GNU Guile Reference Manual}). However, there are major differences:
11188 Gexps are meant to be written to a file and run or manipulated by other
11192 When a high-level object such as a package or derivation is unquoted
11193 inside a gexp, the result is as if its output file name had been
11197 Gexps carry information about the packages or derivations they refer to,
11198 and these dependencies are automatically added as inputs to the build
11199 processes that use them.
11202 @cindex lowering, of high-level objects in gexps
11203 This mechanism is not limited to package and derivation
11204 objects: @dfn{compilers} able to ``lower'' other high-level objects to
11205 derivations or files in the store can be defined,
11206 such that these objects can also be inserted
11207 into gexps. For example, a useful type of high-level objects that can be
11208 inserted in a gexp is ``file-like objects'', which make it easy to
11209 add files to the store and to refer to them in
11210 derivations and such (see @code{local-file} and @code{plain-file}
11213 To illustrate the idea, here is an example of a gexp:
11220 (symlink (string-append #$coreutils "/bin/ls")
11224 This gexp can be passed to @code{gexp->derivation}; we obtain a
11225 derivation that builds a directory containing exactly one symlink to
11226 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
11229 (gexp->derivation "the-thing" build-exp)
11232 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
11233 substituted to the reference to the @var{coreutils} package in the
11234 actual build code, and @var{coreutils} is automatically made an input to
11235 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
11236 output)}) is replaced by a string containing the directory name of the
11237 output of the derivation.
11239 @cindex cross compilation
11240 In a cross-compilation context, it is useful to distinguish between
11241 references to the @emph{native} build of a package---that can run on the
11242 host---versus references to cross builds of a package. To that end, the
11243 @code{#+} plays the same role as @code{#$}, but is a reference to a
11244 native package build:
11247 (gexp->derivation "vi"
11250 (mkdir (string-append #$output "/bin"))
11251 (system* (string-append #+coreutils "/bin/ln")
11253 (string-append #$emacs "/bin/emacs")
11254 (string-append #$output "/bin/vi")))
11255 #:target "aarch64-linux-gnu")
11259 In the example above, the native build of @var{coreutils} is used, so
11260 that @command{ln} can actually run on the host; but then the
11261 cross-compiled build of @var{emacs} is referenced.
11263 @cindex imported modules, for gexps
11264 @findex with-imported-modules
11265 Another gexp feature is @dfn{imported modules}: sometimes you want to be
11266 able to use certain Guile modules from the ``host environment'' in the
11267 gexp, so those modules should be imported in the ``build environment''.
11268 The @code{with-imported-modules} form allows you to express that:
11271 (let ((build (with-imported-modules '((guix build utils))
11273 (use-modules (guix build utils))
11274 (mkdir-p (string-append #$output "/bin"))))))
11275 (gexp->derivation "empty-dir"
11278 (display "success!\n")
11283 In this example, the @code{(guix build utils)} module is automatically
11284 pulled into the isolated build environment of our gexp, such that
11285 @code{(use-modules (guix build utils))} works as expected.
11287 @cindex module closure
11288 @findex source-module-closure
11289 Usually you want the @emph{closure} of the module to be imported---i.e.,
11290 the module itself and all the modules it depends on---rather than just
11291 the module; failing to do that, attempts to use the module will fail
11292 because of missing dependent modules. The @code{source-module-closure}
11293 procedure computes the closure of a module by looking at its source file
11294 headers, which comes in handy in this case:
11297 (use-modules (guix modules)) ;for 'source-module-closure'
11299 (with-imported-modules (source-module-closure
11300 '((guix build utils)
11301 (gnu build image)))
11302 (gexp->derivation "something-with-vms"
11304 (use-modules (guix build utils)
11309 @cindex extensions, for gexps
11310 @findex with-extensions
11311 In the same vein, sometimes you want to import not just pure-Scheme
11312 modules, but also ``extensions'' such as Guile bindings to C libraries
11313 or other ``full-blown'' packages. Say you need the @code{guile-json}
11314 package available on the build side, here's how you would do it:
11317 (use-modules (gnu packages guile)) ;for 'guile-json'
11319 (with-extensions (list guile-json)
11320 (gexp->derivation "something-with-json"
11322 (use-modules (json))
11326 The syntactic form to construct gexps is summarized below.
11328 @deffn {Scheme Syntax} #~@var{exp}
11329 @deffnx {Scheme Syntax} (gexp @var{exp})
11330 Return a G-expression containing @var{exp}. @var{exp} may contain one
11331 or more of the following forms:
11335 @itemx (ungexp @var{obj})
11336 Introduce a reference to @var{obj}. @var{obj} may have one of the
11337 supported types, for example a package or a
11338 derivation, in which case the @code{ungexp} form is replaced by its
11339 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
11341 If @var{obj} is a list, it is traversed and references to supported
11342 objects are substituted similarly.
11344 If @var{obj} is another gexp, its contents are inserted and its
11345 dependencies are added to those of the containing gexp.
11347 If @var{obj} is another kind of object, it is inserted as is.
11349 @item #$@var{obj}:@var{output}
11350 @itemx (ungexp @var{obj} @var{output})
11351 This is like the form above, but referring explicitly to the
11352 @var{output} of @var{obj}---this is useful when @var{obj} produces
11353 multiple outputs (@pxref{Packages with Multiple Outputs}).
11356 @itemx #+@var{obj}:output
11357 @itemx (ungexp-native @var{obj})
11358 @itemx (ungexp-native @var{obj} @var{output})
11359 Same as @code{ungexp}, but produces a reference to the @emph{native}
11360 build of @var{obj} when used in a cross compilation context.
11362 @item #$output[:@var{output}]
11363 @itemx (ungexp output [@var{output}])
11364 Insert a reference to derivation output @var{output}, or to the main
11365 output when @var{output} is omitted.
11367 This only makes sense for gexps passed to @code{gexp->derivation}.
11369 @item #$@@@var{lst}
11370 @itemx (ungexp-splicing @var{lst})
11371 Like the above, but splices the contents of @var{lst} inside the
11374 @item #+@@@var{lst}
11375 @itemx (ungexp-native-splicing @var{lst})
11376 Like the above, but refers to native builds of the objects listed in
11381 G-expressions created by @code{gexp} or @code{#~} are run-time objects
11382 of the @code{gexp?} type (see below).
11385 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
11386 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
11387 in their execution environment.
11389 Each item in @var{modules} can be the name of a module, such as
11390 @code{(guix build utils)}, or it can be a module name, followed by an
11391 arrow, followed by a file-like object:
11394 `((guix build utils)
11396 ((guix config) => ,(scheme-file "config.scm"
11397 #~(define-module @dots{}))))
11401 In the example above, the first two modules are taken from the search
11402 path, and the last one is created from the given file-like object.
11404 This form has @emph{lexical} scope: it has an effect on the gexps
11405 directly defined in @var{body}@dots{}, but not on those defined, say, in
11406 procedures called from @var{body}@dots{}.
11409 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
11410 Mark the gexps defined in @var{body}@dots{} as requiring
11411 @var{extensions} in their build and execution environment.
11412 @var{extensions} is typically a list of package objects such as those
11413 defined in the @code{(gnu packages guile)} module.
11415 Concretely, the packages listed in @var{extensions} are added to the
11416 load path while compiling imported modules in @var{body}@dots{}; they
11417 are also added to the load path of the gexp returned by
11421 @deffn {Scheme Procedure} gexp? @var{obj}
11422 Return @code{#t} if @var{obj} is a G-expression.
11425 G-expressions are meant to be written to disk, either as code building
11426 some derivation, or as plain files in the store. The monadic procedures
11427 below allow you to do that (@pxref{The Store Monad}, for more
11428 information about monads).
11430 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
11431 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
11432 [#:hash #f] [#:hash-algo #f] @
11433 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
11434 [#:module-path @code{%load-path}] @
11435 [#:effective-version "2.2"] @
11436 [#:references-graphs #f] [#:allowed-references #f] @
11437 [#:disallowed-references #f] @
11438 [#:leaked-env-vars #f] @
11439 [#:script-name (string-append @var{name} "-builder")] @
11440 [#:deprecation-warnings #f] @
11441 [#:local-build? #f] [#:substitutable? #t] @
11442 [#:properties '()] [#:guile-for-build #f]
11443 Return a derivation @var{name} that runs @var{exp} (a gexp) with
11444 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
11445 stored in a file called @var{script-name}. When @var{target} is true,
11446 it is used as the cross-compilation target triplet for packages referred
11449 @var{modules} is deprecated in favor of @code{with-imported-modules}.
11451 make @var{modules} available in the evaluation context of @var{exp};
11452 @var{modules} is a list of names of Guile modules searched in
11453 @var{module-path} to be copied in the store, compiled, and made available in
11454 the load path during the execution of @var{exp}---e.g., @code{((guix
11455 build utils) (guix build gnu-build-system))}.
11457 @var{effective-version} determines the string to use when adding extensions of
11458 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
11460 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
11463 When @var{references-graphs} is true, it must be a list of tuples of one of the
11467 (@var{file-name} @var{package})
11468 (@var{file-name} @var{package} @var{output})
11469 (@var{file-name} @var{derivation})
11470 (@var{file-name} @var{derivation} @var{output})
11471 (@var{file-name} @var{store-item})
11474 The right-hand-side of each element of @var{references-graphs} is automatically made
11475 an input of the build process of @var{exp}. In the build environment, each
11476 @var{file-name} contains the reference graph of the corresponding item, in a simple
11479 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
11480 In the latter case, the list denotes store items that the result is allowed to
11481 refer to. Any reference to another store item will lead to a build error.
11482 Similarly for @var{disallowed-references}, which can list items that must not be
11483 referenced by the outputs.
11485 @var{deprecation-warnings} determines whether to show deprecation warnings while
11486 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
11488 The other arguments are as for @code{derivation} (@pxref{Derivations}).
11491 @cindex file-like objects
11492 The @code{local-file}, @code{plain-file}, @code{computed-file},
11493 @code{program-file}, and @code{scheme-file} procedures below return
11494 @dfn{file-like objects}. That is, when unquoted in a G-expression,
11495 these objects lead to a file in the store. Consider this G-expression:
11498 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
11499 #$(local-file "/tmp/my-nscd.conf"))
11502 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
11503 to the store. Once expanded, for instance @i{via}
11504 @code{gexp->derivation}, the G-expression refers to that copy under
11505 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
11506 does not have any effect on what the G-expression does.
11507 @code{plain-file} can be used similarly; it differs in that the file
11508 content is directly passed as a string.
11510 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
11511 [#:recursive? #f] [#:select? (const #t)]
11512 Return an object representing local file @var{file} to add to the store;
11513 this object can be used in a gexp. If @var{file} is a literal string
11514 denoting a relative file name, it is looked up relative to the source
11515 file where it appears; if @var{file} is not a literal string, it is
11516 looked up relative to the current working directory at run time.
11517 @var{file} will be added to the store under @var{name}--by default the
11518 base name of @var{file}.
11520 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
11521 designates a flat file and @var{recursive?} is true, its contents are added, and its
11522 permission bits are kept.
11524 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11525 @var{stat})} for each directory entry, where @var{file} is the entry's
11526 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11527 entries for which @var{select?} does not return true.
11529 This is the declarative counterpart of the @code{interned-file} monadic
11530 procedure (@pxref{The Store Monad, @code{interned-file}}).
11533 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
11534 Return an object representing a text file called @var{name} with the given
11535 @var{content} (a string or a bytevector) to be added to the store.
11537 This is the declarative counterpart of @code{text-file}.
11540 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
11541 [#:local-build? #t]
11543 Return an object representing the store item @var{name}, a file or
11544 directory computed by @var{gexp}. When @var{local-build?} is true (the
11545 default), the derivation is built locally. @var{options} is a list of
11546 additional arguments to pass to @code{gexp->derivation}.
11548 This is the declarative counterpart of @code{gexp->derivation}.
11551 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
11552 [#:guile (default-guile)] [#:module-path %load-path] @
11553 [#:system (%current-system)] [#:target #f]
11554 Return an executable script @var{name} that runs @var{exp} using
11555 @var{guile}, with @var{exp}'s imported modules in its search path.
11556 Look up @var{exp}'s modules in @var{module-path}.
11558 The example below builds a script that simply invokes the @command{ls}
11562 (use-modules (guix gexp) (gnu packages base))
11564 (gexp->script "list-files"
11565 #~(execl #$(file-append coreutils "/bin/ls")
11569 When ``running'' it through the store (@pxref{The Store Monad,
11570 @code{run-with-store}}), we obtain a derivation that produces an
11571 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
11574 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
11576 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
11580 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
11581 [#:guile #f] [#:module-path %load-path]
11582 Return an object representing the executable store item @var{name} that
11583 runs @var{gexp}. @var{guile} is the Guile package used to execute that
11584 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
11586 This is the declarative counterpart of @code{gexp->script}.
11589 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
11590 [#:set-load-path? #t] [#:module-path %load-path] @
11592 [#:guile (default-guile)]
11593 Return a derivation that builds a file @var{name} containing @var{exp}.
11594 When @var{splice?} is true, @var{exp} is considered to be a list of
11595 expressions that will be spliced in the resulting file.
11597 When @var{set-load-path?} is true, emit code in the resulting file to
11598 set @code{%load-path} and @code{%load-compiled-path} to honor
11599 @var{exp}'s imported modules. Look up @var{exp}'s modules in
11602 The resulting file holds references to all the dependencies of @var{exp}
11603 or a subset thereof.
11606 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
11607 [#:splice? #f] [#:set-load-path? #t]
11608 Return an object representing the Scheme file @var{name} that contains
11611 This is the declarative counterpart of @code{gexp->file}.
11614 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
11615 Return as a monadic value a derivation that builds a text file
11616 containing all of @var{text}. @var{text} may list, in addition to
11617 strings, objects of any type that can be used in a gexp: packages,
11618 derivations, local file objects, etc. The resulting store file holds
11619 references to all these.
11621 This variant should be preferred over @code{text-file} anytime the file
11622 to create will reference items from the store. This is typically the
11623 case when building a configuration file that embeds store file names,
11627 (define (profile.sh)
11628 ;; Return the name of a shell script in the store that
11629 ;; initializes the 'PATH' environment variable.
11630 (text-file* "profile.sh"
11631 "export PATH=" coreutils "/bin:"
11632 grep "/bin:" sed "/bin\n"))
11635 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
11636 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
11637 preventing them from being garbage-collected during its lifetime.
11640 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
11641 Return an object representing store file @var{name} containing
11642 @var{text}. @var{text} is a sequence of strings and file-like objects,
11646 (mixed-text-file "profile"
11647 "export PATH=" coreutils "/bin:" grep "/bin")
11650 This is the declarative counterpart of @code{text-file*}.
11653 @deffn {Scheme Procedure} file-union @var{name} @var{files}
11654 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
11655 Each item in @var{files} must be a two-element list where the first element is the
11656 file name to use in the new directory, and the second element is a gexp
11657 denoting the target file. Here's an example:
11661 `(("hosts" ,(plain-file "hosts"
11662 "127.0.0.1 localhost"))
11663 ("bashrc" ,(plain-file "bashrc"
11664 "alias ls='ls --color=auto'"))))
11667 This yields an @code{etc} directory containing these two files.
11670 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
11671 Return a directory that is the union of @var{things}, where @var{things} is a list of
11672 file-like objects denoting directories. For example:
11675 (directory-union "guile+emacs" (list guile emacs))
11678 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
11681 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
11682 Return a file-like object that expands to the concatenation of @var{obj}
11683 and @var{suffix}, where @var{obj} is a lowerable object and each
11684 @var{suffix} is a string.
11686 As an example, consider this gexp:
11689 (gexp->script "run-uname"
11690 #~(system* #$(file-append coreutils
11694 The same effect could be achieved with:
11697 (gexp->script "run-uname"
11698 #~(system* (string-append #$coreutils
11702 There is one difference though: in the @code{file-append} case, the
11703 resulting script contains the absolute file name as a string, whereas in
11704 the second case, the resulting script contains a @code{(string-append
11705 @dots{})} expression to construct the file name @emph{at run time}.
11708 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
11709 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
11710 Bind @var{system} to the currently targeted system---e.g.,
11711 @code{"x86_64-linux"}---within @var{body}.
11713 In the second case, additionally bind @var{target} to the current
11714 cross-compilation target---a GNU triplet such as
11715 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
11718 @code{let-system} is useful in the occasional case where the object
11719 spliced into the gexp depends on the target system, as in this example:
11723 #+(let-system system
11724 (cond ((string-prefix? "armhf-" system)
11725 (file-append qemu "/bin/qemu-system-arm"))
11726 ((string-prefix? "x86_64-" system)
11727 (file-append qemu "/bin/qemu-system-x86_64"))
11729 (error "dunno!"))))
11730 "-net" "user" #$image)
11734 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
11735 This macro is similar to the @code{parameterize} form for
11736 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
11737 Guile Reference Manual}). The key difference is that it takes effect
11738 when the file-like object returned by @var{exp} is lowered to a
11739 derivation or store item.
11741 A typical use of @code{with-parameters} is to force the system in effect
11742 for a given object:
11745 (with-parameters ((%current-system "i686-linux"))
11749 The example above returns an object that corresponds to the i686 build
11750 of Coreutils, regardless of the current value of @code{%current-system}.
11754 Of course, in addition to gexps embedded in ``host'' code, there are
11755 also modules containing build tools. To make it clear that they are
11756 meant to be used in the build stratum, these modules are kept in the
11757 @code{(guix build @dots{})} name space.
11759 @cindex lowering, of high-level objects in gexps
11760 Internally, high-level objects are @dfn{lowered}, using their compiler,
11761 to either derivations or store items. For instance, lowering a package
11762 yields a derivation, and lowering a @code{plain-file} yields a store
11763 item. This is achieved using the @code{lower-object} monadic procedure.
11765 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
11767 Return as a value in @code{%store-monad} the derivation or store item
11768 corresponding to @var{obj} for @var{system}, cross-compiling for
11769 @var{target} if @var{target} is true. @var{obj} must be an object that
11770 has an associated gexp compiler, such as a @code{<package>}.
11773 @deffn {Procedure} gexp->approximate-sexp @var{gexp}
11774 Sometimes, it may be useful to convert a G-exp into a S-exp. For
11775 example, some linters (@pxref{Invoking guix lint}) peek into the build
11776 phases of a package to detect potential problems. This conversion can
11777 be achieved with this procedure. However, some information can be lost
11778 in the process. More specifically, lowerable objects will be silently
11779 replaced with some arbitrary object -- currently the list
11780 @code{(*approximate*)}, but this may change.
11783 @node Invoking guix repl
11784 @section Invoking @command{guix repl}
11786 @cindex REPL, read-eval-print loop, script
11787 The @command{guix repl} command makes it easier to program Guix in Guile
11788 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
11789 programming (@pxref{Using Guile Interactively,,, guile,
11790 GNU Guile Reference Manual}), or by running Guile scripts
11791 (@pxref{Running Guile Scripts,,, guile,
11792 GNU Guile Reference Manual}).
11793 Compared to just launching the @command{guile}
11794 command, @command{guix repl} guarantees that all the Guix modules and all its
11795 dependencies are available in the search path.
11797 The general syntax is:
11800 guix repl @var{options} [@var{file} @var{args}]
11803 When a @var{file} argument is provided, @var{file} is
11804 executed as a Guile scripts:
11807 guix repl my-script.scm
11810 To pass arguments to the script, use @code{--} to prevent them from
11811 being interpreted as arguments to @command{guix repl} itself:
11814 guix repl -- my-script.scm --input=foo.txt
11817 To make a script executable directly from the shell, using the guix
11818 executable that is on the user's search path, add the following two
11819 lines at the top of the script:
11822 @code{#!/usr/bin/env -S guix repl --}
11826 Without a file name argument, a Guile REPL is started, allowing for
11827 interactive use (@pxref{Using Guix Interactively}):
11831 scheme@@(guile-user)> ,use (gnu packages base)
11832 scheme@@(guile-user)> coreutils
11833 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
11837 In addition, @command{guix repl} implements a simple machine-readable REPL
11838 protocol for use by @code{(guix inferior)}, a facility to interact with
11839 @dfn{inferiors}, separate processes running a potentially different revision
11842 The available options are as follows:
11845 @item --type=@var{type}
11846 @itemx -t @var{type}
11847 Start a REPL of the given @var{TYPE}, which can be one of the following:
11851 This is default, and it spawns a standard full-featured Guile REPL.
11853 Spawn a REPL that uses the machine-readable protocol. This is the protocol
11854 that the @code{(guix inferior)} module speaks.
11857 @item --listen=@var{endpoint}
11858 By default, @command{guix repl} reads from standard input and writes to
11859 standard output. When this option is passed, it will instead listen for
11860 connections on @var{endpoint}. Here are examples of valid options:
11863 @item --listen=tcp:37146
11864 Accept connections on localhost on port 37146.
11866 @item --listen=unix:/tmp/socket
11867 Accept connections on the Unix-domain socket @file{/tmp/socket}.
11870 @item --load-path=@var{directory}
11871 @itemx -L @var{directory}
11872 Add @var{directory} to the front of the package module search path
11873 (@pxref{Package Modules}).
11875 This allows users to define their own packages and make them visible to
11876 the script or REPL.
11879 Inhibit loading of the @file{~/.guile} file. By default, that
11880 configuration file is loaded when spawning a @code{guile} REPL.
11883 @node Using Guix Interactively
11884 @section Using Guix Interactively
11886 @cindex interactive use
11887 @cindex REPL, read-eval-print loop
11888 The @command{guix repl} command gives you access to a warm and friendly
11889 @dfn{read-eval-print loop} (REPL) (@pxref{Invoking guix repl}). If
11890 you're getting into Guix programming---defining your own packages,
11891 writing manifests, defining services for Guix System or Guix Home,
11892 etc.---you will surely find it convenient to toy with ideas at the REPL.
11894 If you use Emacs, the most convenient way to do that is with Geiser
11895 (@pxref{The Perfect Setup}), but you do not have to use Emacs to enjoy
11896 the REPL@. When using @command{guix repl} or @command{guile} in the
11897 terminal, we recommend using Readline for completion and Colorized to
11898 get colorful output. To do that, you can run:
11901 guix install guile guile-readline guile-colorized
11905 ... and then create a @file{.guile} file in your home directory containing
11909 (use-modules (ice-9 readline) (ice-9 colorized))
11911 (activate-readline)
11912 (activate-colorized)
11915 The REPL lets you evaluate Scheme code; you type a Scheme expression at
11916 the prompt, and the REPL prints what it evaluates to:
11920 scheme@@(guix-user)> (+ 2 3)
11922 scheme@@(guix-user)> (string-append "a" "b")
11926 It becomes interesting when you start fiddling with Guix at the REPL.
11927 The first thing you'll want to do is to ``import'' the @code{(guix)}
11928 module, which gives access to the main part of the programming
11929 interface, and perhaps a bunch of useful Guix modules. You could type
11930 @code{(use-modules (guix))}, which is valid Scheme code to import a
11931 module (@pxref{Using Guile Modules,,, guile, GNU Guile Reference
11932 Manual}), but the REPL provides the @code{use} @dfn{command} as a
11933 shorthand notation (@pxref{REPL Commands,,, guile, GNU Guile Reference
11937 scheme@@(guix-user)> ,use (guix)
11938 scheme@@(guix-user)> ,use (gnu packages base)
11941 Notice that REPL commands are introduced by a leading comma. A REPL
11942 command like @code{use} is not valid Scheme code; it's interpreted
11943 specially by the REPL.
11945 Guix extends the Guile REPL with additional commands for convenience.
11946 Among those, the @code{build} command comes in handy: it ensures that
11947 the given file-like object is built, building it if needed, and returns
11948 its output file name(s). In the example below, we build the
11949 @code{coreutils} and @code{grep} packages, as well as a ``computed
11950 file'' (@pxref{G-Expressions, @code{computed-file}}), and we use the
11951 @code{scandir} procedure to list the files in Grep's @code{/bin}
11955 scheme@@(guix-user)> ,build coreutils
11956 $1 = "/gnu/store/@dots{}-coreutils-8.32-debug"
11957 $2 = "/gnu/store/@dots{}-coreutils-8.32"
11958 scheme@@(guix-user)> ,build grep
11959 $3 = "/gnu/store/@dots{}-grep-3.6"
11960 scheme@@(guix-user)> ,build (computed-file "x" #~(mkdir #$output))
11961 building /gnu/store/@dots{}-x.drv...
11962 $4 = "/gnu/store/@dots{}-x"
11963 scheme@@(guix-user)> ,use(ice-9 ftw)
11964 scheme@@(guix-user)> (scandir (string-append $3 "/bin"))
11965 $5 = ("." ".." "egrep" "fgrep" "grep")
11968 At a lower-level, a useful command is @code{lower}: it takes a file-like
11969 object and ``lowers'' it into a derivation (@pxref{Derivations}) or a
11973 scheme@@(guix-user)> ,lower grep
11974 $6 = #<derivation /gnu/store/@dots{}-grep-3.6.drv => /gnu/store/@dots{}-grep-3.6 7f0e639115f0>
11975 scheme@@(guix-user)> ,lower (plain-file "x" "Hello!")
11976 $7 = "/gnu/store/@dots{}-x"
11979 The full list of REPL commands can be seen by typing @code{,help guix}
11980 and is given below for reference.
11982 @deffn {REPL command} build @var{object}
11983 Lower @var{object} and build it if it's not already built, returning its
11984 output file name(s).
11987 @deffn {REPL command} lower @var{object}
11988 Lower @var{object} into a derivation or store file name and return it.
11991 @deffn {REPL command} verbosity @var{level}
11992 Change build verbosity to @var{level}.
11994 This is similar to the @option{--verbosity} command-line option
11995 (@pxref{Common Build Options}): level 0 means total silence, level 1
11996 shows build events only, and higher levels print build logs.
11999 @deffn {REPL command} run-in-store @var{exp}
12000 Run @var{exp}, a monadic expresssion, through the store monad.
12001 @xref{The Store Monad}, for more information.
12004 @deffn {REPL command} enter-store-monad
12005 Enter a new REPL to evaluate monadic expressions (@pxref{The Store
12006 Monad}). You can quit this ``inner'' REPL by typing @code{,q}.
12009 @c *********************************************************************
12013 This section describes Guix command-line utilities. Some of them are
12014 primarily targeted at developers and users who write new package
12015 definitions, while others are more generally useful. They complement
12016 the Scheme programming interface of Guix in a convenient way.
12019 * Invoking guix build:: Building packages from the command line.
12020 * Invoking guix edit:: Editing package definitions.
12021 * Invoking guix download:: Downloading a file and printing its hash.
12022 * Invoking guix hash:: Computing the cryptographic hash of a file.
12023 * Invoking guix import:: Importing package definitions.
12024 * Invoking guix refresh:: Updating package definitions.
12025 * Invoking guix style:: Styling package definitions.
12026 * Invoking guix lint:: Finding errors in package definitions.
12027 * Invoking guix size:: Profiling disk usage.
12028 * Invoking guix graph:: Visualizing the graph of packages.
12029 * Invoking guix publish:: Sharing substitutes.
12030 * Invoking guix challenge:: Challenging substitute servers.
12031 * Invoking guix copy:: Copying to and from a remote store.
12032 * Invoking guix container:: Process isolation.
12033 * Invoking guix weather:: Assessing substitute availability.
12034 * Invoking guix processes:: Listing client processes.
12037 @node Invoking guix build
12038 @section Invoking @command{guix build}
12040 @cindex package building
12041 @cindex @command{guix build}
12042 The @command{guix build} command builds packages or derivations and
12043 their dependencies, and prints the resulting store paths. Note that it
12044 does not modify the user's profile---this is the job of the
12045 @command{guix package} command (@pxref{Invoking guix package}). Thus,
12046 it is mainly useful for distribution developers.
12048 The general syntax is:
12051 guix build @var{options} @var{package-or-derivation}@dots{}
12054 As an example, the following command builds the latest versions of Emacs
12055 and of Guile, displays their build logs, and finally displays the
12056 resulting directories:
12059 guix build emacs guile
12062 Similarly, the following command builds all the available packages:
12065 guix build --quiet --keep-going \
12066 $(guix package -A | awk '@{ print $1 "@@" $2 @}')
12069 @var{package-or-derivation} may be either the name of a package found in
12070 the software distribution such as @code{coreutils} or
12071 @code{coreutils@@8.20}, or a derivation such as
12072 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
12073 package with the corresponding name (and optionally version) is searched
12074 for among the GNU distribution modules (@pxref{Package Modules}).
12076 Alternatively, the @option{--expression} option may be used to specify a
12077 Scheme expression that evaluates to a package; this is useful when
12078 disambiguating among several same-named packages or package variants is
12081 There may be zero or more @var{options}. The available options are
12082 described in the subsections below.
12085 * Common Build Options:: Build options for most commands.
12086 * Package Transformation Options:: Creating variants of packages.
12087 * Additional Build Options:: Options specific to 'guix build'.
12088 * Debugging Build Failures:: Real life packaging experience.
12091 @node Common Build Options
12092 @subsection Common Build Options
12094 A number of options that control the build process are common to
12095 @command{guix build} and other commands that can spawn builds, such as
12096 @command{guix package} or @command{guix archive}. These are the
12101 @item --load-path=@var{directory}
12102 @itemx -L @var{directory}
12103 Add @var{directory} to the front of the package module search path
12104 (@pxref{Package Modules}).
12106 This allows users to define their own packages and make them visible to
12107 the command-line tools.
12109 @item --keep-failed
12111 Keep the build tree of failed builds. Thus, if a build fails, its build
12112 tree is kept under @file{/tmp}, in a directory whose name is shown at
12113 the end of the build log. This is useful when debugging build issues.
12114 @xref{Debugging Build Failures}, for tips and tricks on how to debug
12117 This option implies @option{--no-offload}, and it has no effect when
12118 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
12119 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
12123 Keep going when some of the derivations fail to build; return only once
12124 all the builds have either completed or failed.
12126 The default behavior is to stop as soon as one of the specified
12127 derivations has failed.
12131 Do not build the derivations.
12133 @anchor{fallback-option}
12135 When substituting a pre-built binary fails, fall back to building
12136 packages locally (@pxref{Substitution Failure}).
12138 @item --substitute-urls=@var{urls}
12139 @anchor{client-substitute-urls}
12140 Consider @var{urls} the whitespace-separated list of substitute source
12141 URLs, overriding the default list of URLs of @command{guix-daemon}
12142 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
12144 This means that substitutes may be downloaded from @var{urls}, provided
12145 they are signed by a key authorized by the system administrator
12146 (@pxref{Substitutes}).
12148 When @var{urls} is the empty string, substitutes are effectively
12151 @item --no-substitutes
12152 Do not use substitutes for build products. That is, always build things
12153 locally instead of allowing downloads of pre-built binaries
12154 (@pxref{Substitutes}).
12157 Do not ``graft'' packages. In practice, this means that package updates
12158 available as grafts are not applied. @xref{Security Updates}, for more
12159 information on grafts.
12161 @item --rounds=@var{n}
12162 Build each derivation @var{n} times in a row, and raise an error if
12163 consecutive build results are not bit-for-bit identical.
12165 This is a useful way to detect non-deterministic builds processes.
12166 Non-deterministic build processes are a problem because they make it
12167 practically impossible for users to @emph{verify} whether third-party
12168 binaries are genuine. @xref{Invoking guix challenge}, for more.
12170 When used in conjunction with @option{--keep-failed}, the differing
12171 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12172 This makes it easy to look for differences between the two results.
12175 Do not use offload builds to other machines (@pxref{Daemon Offload
12176 Setup}). That is, always build things locally instead of offloading
12177 builds to remote machines.
12179 @item --max-silent-time=@var{seconds}
12180 When the build or substitution process remains silent for more than
12181 @var{seconds}, terminate it and report a build failure.
12183 By default, the daemon's setting is honored (@pxref{Invoking
12184 guix-daemon, @option{--max-silent-time}}).
12186 @item --timeout=@var{seconds}
12187 Likewise, when the build or substitution process lasts for more than
12188 @var{seconds}, terminate it and report a build failure.
12190 By default, the daemon's setting is honored (@pxref{Invoking
12191 guix-daemon, @option{--timeout}}).
12193 @c Note: This option is actually not part of %standard-build-options but
12194 @c most programs honor it.
12195 @cindex verbosity, of the command-line tools
12196 @cindex build logs, verbosity
12197 @item -v @var{level}
12198 @itemx --verbosity=@var{level}
12199 Use the given verbosity @var{level}, an integer. Choosing 0 means that
12200 no output is produced, 1 is for quiet output; 2 is similar to 1 but it
12201 additionally displays download URLs; 3 shows all the build log output on
12204 @item --cores=@var{n}
12206 Allow the use of up to @var{n} CPU cores for the build. The special
12207 value @code{0} means to use as many CPU cores as available.
12209 @item --max-jobs=@var{n}
12211 Allow at most @var{n} build jobs in parallel. @xref{Invoking
12212 guix-daemon, @option{--max-jobs}}, for details about this option and the
12213 equivalent @command{guix-daemon} option.
12215 @item --debug=@var{level}
12216 Produce debugging output coming from the build daemon. @var{level} must be an
12217 integer between 0 and 5; higher means more verbose output. Setting a level of
12218 4 or more may be helpful when debugging setup issues with the build daemon.
12222 Behind the scenes, @command{guix build} is essentially an interface to
12223 the @code{package-derivation} procedure of the @code{(guix packages)}
12224 module, and to the @code{build-derivations} procedure of the @code{(guix
12225 derivations)} module.
12227 In addition to options explicitly passed on the command line,
12228 @command{guix build} and other @command{guix} commands that support
12229 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
12231 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
12232 Users can define this variable to a list of command line options that
12233 will automatically be used by @command{guix build} and other
12234 @command{guix} commands that can perform builds, as in the example
12238 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
12241 These options are parsed independently, and the result is appended to
12242 the parsed command-line options.
12246 @node Package Transformation Options
12247 @subsection Package Transformation Options
12249 @cindex package variants
12250 Another set of command-line options supported by @command{guix build}
12251 and also @command{guix package} are @dfn{package transformation
12252 options}. These are options that make it possible to define @dfn{package
12253 variants}---for instance, packages built from different source code.
12254 This is a convenient way to create customized packages on the fly
12255 without having to type in the definitions of package variants
12256 (@pxref{Defining Packages}).
12258 Package transformation options are preserved across upgrades:
12259 @command{guix upgrade} attempts to apply transformation options
12260 initially used when creating the profile to the upgraded packages.
12262 The available options are listed below. Most commands support them and
12263 also support a @option{--help-transform} option that lists all the
12264 available options and a synopsis (these options are not shown in the
12265 @option{--help} output for brevity).
12269 @cindex performance, tuning code
12270 @cindex optimization, of package code
12271 @cindex tuning, of package code
12272 @cindex SIMD support
12273 @cindex tunable packages
12274 @cindex package multi-versioning
12275 @item --tune[=@var{cpu}]
12276 Use versions of the packages marked as ``tunable'' optimized for
12277 @var{cpu}. When @var{cpu} is @code{native}, or when it is omitted, tune
12278 for the CPU on which the @command{guix} command is running.
12280 Valid @var{cpu} names are those recognized by the underlying compiler,
12281 by default the GNU Compiler Collection. On x86_64 processors, this
12282 includes CPU names such as @code{nehalem}, @code{haswell}, and
12283 @code{skylake} (@pxref{x86 Options, @code{-march},, gcc, Using the GNU
12284 Compiler Collection (GCC)}).
12286 As new generations of CPUs come out, they augment the standard
12287 instruction set architecture (ISA) with additional instructions, in
12288 particular instructions for single-instruction/multiple-data (SIMD)
12289 parallel processing. For example, while Core2 and Skylake CPUs both
12290 implement the x86_64 ISA, only the latter supports AVX2 SIMD
12293 The primary gain one can expect from @option{--tune} is for programs
12294 that can make use of those SIMD capabilities @emph{and} that do not
12295 already have a mechanism to select the right optimized code at run time.
12296 Packages that have the @code{tunable?} property set are considered
12297 @dfn{tunable packages} by the @option{--tune} option; a package
12298 definition with the property set looks like this:
12302 (name "hello-simd")
12305 ;; This package may benefit from SIMD extensions so
12306 ;; mark it as "tunable".
12307 (properties '((tunable? . #t))))
12310 Other packages are not considered tunable. This allows Guix to use
12311 generic binaries in the cases where tuning for a specific CPU is
12312 unlikely to provide any gain.
12314 Tuned packages are built with @code{-march=@var{CPU}}; under the hood,
12315 the @option{-march} option is passed to the actual wrapper by a compiler
12316 wrapper. Since the build machine may not be able to run code for the
12317 target CPU micro-architecture, the test suite is not run when building a
12320 To reduce rebuilds to the minimum, tuned packages are @emph{grafted}
12321 onto packages that depend on them (@pxref{Security Updates, grafts}).
12322 Thus, using @option{--no-grafts} cancels the effect of @option{--tune}.
12324 We call this technique @dfn{package multi-versioning}: several variants
12325 of tunable packages may be built, one for each CPU variant. It is the
12326 coarse-grain counterpart of @dfn{function multi-versioning} as
12327 implemented by the GNU tool chain (@pxref{Function Multiversioning,,,
12328 gcc, Using the GNU Compiler Collection (GCC)}).
12330 @item --with-source=@var{source}
12331 @itemx --with-source=@var{package}=@var{source}
12332 @itemx --with-source=@var{package}@@@var{version}=@var{source}
12333 Use @var{source} as the source of @var{package}, and @var{version} as
12334 its version number.
12335 @var{source} must be a file name or a URL, as for @command{guix
12336 download} (@pxref{Invoking guix download}).
12338 When @var{package} is omitted,
12339 it is taken to be the package name specified on the
12340 command line that matches the base of @var{source}---e.g.,
12341 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
12342 package is @code{guile}.
12344 Likewise, when @var{version} is omitted, the version string is inferred from
12345 @var{source}; in the previous example, it is @code{2.0.10}.
12347 This option allows users to try out versions of packages other than the
12348 one provided by the distribution. The example below downloads
12349 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
12350 the @code{ed} package:
12353 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
12356 As a developer, @option{--with-source} makes it easy to test release
12360 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
12363 @dots{} or to build from a checkout in a pristine environment:
12366 $ git clone git://git.sv.gnu.org/guix.git
12367 $ guix build guix --with-source=guix@@1.0=./guix
12370 @item --with-input=@var{package}=@var{replacement}
12371 Replace dependency on @var{package} by a dependency on
12372 @var{replacement}. @var{package} must be a package name, and
12373 @var{replacement} must be a package specification such as @code{guile}
12374 or @code{guile@@1.8}.
12376 For instance, the following command builds Guix, but replaces its
12377 dependency on the current stable version of Guile with a dependency on
12378 the legacy version of Guile, @code{guile@@2.0}:
12381 guix build --with-input=guile=guile@@2.0 guix
12384 This is a recursive, deep replacement. So in this example, both
12385 @code{guix} and its dependency @code{guile-json} (which also depends on
12386 @code{guile}) get rebuilt against @code{guile@@2.0}.
12388 This is implemented using the @code{package-input-rewriting} Scheme
12389 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
12391 @item --with-graft=@var{package}=@var{replacement}
12392 This is similar to @option{--with-input} but with an important difference:
12393 instead of rebuilding the whole dependency chain, @var{replacement} is
12394 built and then @dfn{grafted} onto the binaries that were initially
12395 referring to @var{package}. @xref{Security Updates}, for more
12396 information on grafts.
12398 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
12399 and all its dependencies, replacing references to the version of GnuTLS
12400 they currently refer to:
12403 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
12406 This has the advantage of being much faster than rebuilding everything.
12407 But there is a caveat: it works if and only if @var{package} and
12408 @var{replacement} are strictly compatible---for example, if they provide
12409 a library, the application binary interface (ABI) of those libraries
12410 must be compatible. If @var{replacement} is somehow incompatible with
12411 @var{package}, then the resulting package may be unusable. Use with
12414 @cindex debugging info, rebuilding
12415 @item --with-debug-info=@var{package}
12416 Build @var{package} in a way that preserves its debugging info and graft
12417 it onto packages that depend on it. This is useful if @var{package}
12418 does not already provide debugging info as a @code{debug} output
12419 (@pxref{Installing Debugging Files}).
12421 For example, suppose you're experiencing a crash in Inkscape and would
12422 like to see what's up in GLib, a library deep down in Inkscape's
12423 dependency graph. GLib lacks a @code{debug} output, so debugging is
12424 tough. Fortunately, you rebuild GLib with debugging info and tack it on
12428 guix install inkscape --with-debug-info=glib
12431 Only GLib needs to be recompiled so this takes a reasonable amount of
12432 time. @xref{Installing Debugging Files}, for more info.
12435 Under the hood, this option works by passing the @samp{#:strip-binaries?
12436 #f} to the build system of the package of interest (@pxref{Build
12437 Systems}). Most build systems support that option but some do not. In
12438 that case, an error is raised.
12440 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
12441 the case), debugging info will remain unavailable even when
12442 @code{#:strip-binaries?} is false.
12445 @cindex tool chain, changing the build tool chain of a package
12446 @item --with-c-toolchain=@var{package}=@var{toolchain}
12447 This option changes the compilation of @var{package} and everything that
12448 depends on it so that they get built with @var{toolchain} instead of the
12449 default GNU tool chain for C/C++.
12451 Consider this example:
12454 guix build octave-cli \
12455 --with-c-toolchain=fftw=gcc-toolchain@@10 \
12456 --with-c-toolchain=fftwf=gcc-toolchain@@10
12459 The command above builds a variant of the @code{fftw} and @code{fftwf}
12460 packages using version 10 of @code{gcc-toolchain} instead of the default
12461 tool chain, and then builds a variant of the GNU@tie{}Octave
12462 command-line interface using them. GNU@tie{}Octave itself is also built
12463 with @code{gcc-toolchain@@10}.
12465 This other example builds the Hardware Locality (@code{hwloc}) library
12466 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
12470 guix build --with-c-toolchain=hwloc=clang-toolchain \
12471 intel-mpi-benchmarks
12475 There can be application binary interface (ABI) incompatibilities among
12476 tool chains. This is particularly true of the C++ standard library and
12477 run-time support libraries such as that of OpenMP@. By rebuilding all
12478 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
12479 the risks of incompatibility but cannot entirely eliminate them. Choose
12480 @var{package} wisely.
12483 @item --with-git-url=@var{package}=@var{url}
12484 @cindex Git, using the latest commit
12485 @cindex latest commit, building
12486 Build @var{package} from the latest commit of the @code{master} branch of the
12487 Git repository at @var{url}. Git sub-modules of the repository are fetched,
12490 For example, the following command builds the NumPy Python library against the
12491 latest commit of the master branch of Python itself:
12494 guix build python-numpy \
12495 --with-git-url=python=https://github.com/python/cpython
12498 This option can also be combined with @option{--with-branch} or
12499 @option{--with-commit} (see below).
12501 @cindex continuous integration
12502 Obviously, since it uses the latest commit of the given branch, the result of
12503 such a command varies over time. Nevertheless it is a convenient way to
12504 rebuild entire software stacks against the latest commit of one or more
12505 packages. This is particularly useful in the context of continuous
12508 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
12509 consecutive accesses to the same repository. You may want to clean it up once
12510 in a while to save disk space.
12512 @item --with-branch=@var{package}=@var{branch}
12513 Build @var{package} from the latest commit of @var{branch}. If the
12514 @code{source} field of @var{package} is an origin with the @code{git-fetch}
12515 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
12516 repository URL is taken from that @code{source}. Otherwise you have to use
12517 @option{--with-git-url} to specify the URL of the Git repository.
12519 For instance, the following command builds @code{guile-sqlite3} from the
12520 latest commit of its @code{master} branch, and then builds @code{guix} (which
12521 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
12522 specific @code{guile-sqlite3} build:
12525 guix build --with-branch=guile-sqlite3=master cuirass
12528 @item --with-commit=@var{package}=@var{commit}
12529 This is similar to @option{--with-branch}, except that it builds from
12530 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
12531 Git commit SHA1 identifier, a tag, or a @command{git describe} style
12532 identifier such as @code{1.0-3-gabc123}.
12534 @item --with-patch=@var{package}=@var{file}
12535 Add @var{file} to the list of patches applied to @var{package}, where
12536 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
12537 @var{file} must contain a patch; it is applied with the flags specified
12538 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
12539 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
12540 Comparing and Merging Files}).
12542 As an example, the command below rebuilds Coreutils with the GNU C
12543 Library (glibc) patched with the given patch:
12546 guix build coreutils --with-patch=glibc=./glibc-frob.patch
12549 In this example, glibc itself as well as everything that leads to
12550 Coreutils in the dependency graph is rebuilt.
12552 @cindex upstream, latest version
12553 @item --with-latest=@var{package}
12554 So you like living on the bleeding edge? This option is for you! It
12555 replaces occurrences of @var{package} in the dependency graph with its
12556 latest upstream version, as reported by @command{guix refresh}
12557 (@pxref{Invoking guix refresh}).
12559 It does so by determining the latest upstream release of @var{package}
12560 (if possible), downloading it, and authenticating it @emph{if} it comes
12561 with an OpenPGP signature.
12563 As an example, the command below builds Guix against the latest version
12567 guix build guix --with-latest=guile-json
12570 There are limitations. First, in cases where the tool cannot or does
12571 not know how to authenticate source code, you are at risk of running
12572 malicious code; a warning is emitted in this case. Second, this option
12573 simply changes the source used in the existing package definitions,
12574 which is not always sufficient: there might be additional dependencies
12575 that need to be added, patches to apply, and more generally the quality
12576 assurance work that Guix developers normally do will be missing.
12578 You've been warned! In all the other cases, it's a snappy way to stay
12579 on top. We encourage you to submit patches updating the actual package
12580 definitions once you have successfully tested an upgrade
12581 (@pxref{Contributing}).
12583 @cindex test suite, skipping
12584 @item --without-tests=@var{package}
12585 Build @var{package} without running its tests. This can be useful in
12586 situations where you want to skip the lengthy test suite of a
12587 intermediate package, or if a package's test suite fails in a
12588 non-deterministic fashion. It should be used with care because running
12589 the test suite is a good way to ensure a package is working as intended.
12591 Turning off tests leads to a different store item. Consequently, when
12592 using this option, anything that depends on @var{package} must be
12593 rebuilt, as in this example:
12596 guix install --without-tests=python python-notebook
12599 The command above installs @code{python-notebook} on top of
12600 @code{python} built without running its test suite. To do so, it also
12601 rebuilds everything that depends on @code{python}, including
12602 @code{python-notebook} itself.
12604 Internally, @option{--without-tests} relies on changing the
12605 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
12606 Systems}). Note that some packages use a customized @code{check} phase
12607 that does not respect a @code{#:tests? #f} setting. Therefore,
12608 @option{--without-tests} has no effect on these packages.
12612 Wondering how to achieve the same effect using Scheme code, for example
12613 in your manifest, or how to write your own package transformation?
12614 @xref{Defining Package Variants}, for an overview of the programming
12615 interfaces available.
12617 @node Additional Build Options
12618 @subsection Additional Build Options
12620 The command-line options presented below are specific to @command{guix
12627 Build quietly, without displaying the build log; this is equivalent to
12628 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
12629 (or similar) and can always be retrieved using the @option{--log-file} option.
12631 @item --file=@var{file}
12632 @itemx -f @var{file}
12633 Build the package, derivation, or other file-like object that the code within
12634 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
12636 As an example, @var{file} might contain a package definition like this
12637 (@pxref{Defining Packages}):
12640 @include package-hello.scm
12643 The @var{file} may also contain a JSON representation of one or more
12644 package definitions. Running @code{guix build -f} on @file{hello.json}
12645 with the following contents would result in building the packages
12646 @code{myhello} and @code{greeter}:
12649 @verbatiminclude package-hello.json
12652 @item --manifest=@var{manifest}
12653 @itemx -m @var{manifest}
12654 Build all packages listed in the given @var{manifest}
12655 (@pxref{profile-manifest, @option{--manifest}}).
12657 @item --expression=@var{expr}
12658 @itemx -e @var{expr}
12659 Build the package or derivation @var{expr} evaluates to.
12661 For example, @var{expr} may be @code{(@@ (gnu packages guile)
12662 guile-1.8)}, which unambiguously designates this specific variant of
12663 version 1.8 of Guile.
12665 Alternatively, @var{expr} may be a G-expression, in which case it is used
12666 as a build program passed to @code{gexp->derivation}
12667 (@pxref{G-Expressions}).
12669 Lastly, @var{expr} may refer to a zero-argument monadic procedure
12670 (@pxref{The Store Monad}). The procedure must return a derivation as a
12671 monadic value, which is then passed through @code{run-with-store}.
12675 Build the source derivations of the packages, rather than the packages
12678 For instance, @code{guix build -S gcc} returns something like
12679 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
12682 The returned source tarball is the result of applying any patches and
12683 code snippets specified in the package @code{origin} (@pxref{Defining
12686 @cindex source, verification
12687 As with other derivations, the result of building a source derivation
12688 can be verified using the @option{--check} option (@pxref{build-check}).
12689 This is useful to validate that a (potentially already built or
12690 substituted, thus cached) package source matches against its declared
12693 Note that @command{guix build -S} compiles the sources only of the
12694 specified packages. They do not include the sources of statically
12695 linked dependencies and by themselves are insufficient for reproducing
12699 Fetch and return the source of @var{package-or-derivation} and all their
12700 dependencies, recursively. This is a handy way to obtain a local copy
12701 of all the source code needed to build @var{packages}, allowing you to
12702 eventually build them even without network access. It is an extension
12703 of the @option{--source} option and can accept one of the following
12704 optional argument values:
12708 This value causes the @option{--sources} option to behave in the same way
12709 as the @option{--source} option.
12712 Build the source derivations of all packages, including any source that
12713 might be listed as @code{inputs}. This is the default value.
12716 $ guix build --sources tzdata
12717 The following derivations will be built:
12718 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
12719 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12723 Build the source derivations of all packages, as well of all transitive
12724 inputs to the packages. This can be used e.g.@: to
12725 prefetch package source for later offline building.
12728 $ guix build --sources=transitive tzdata
12729 The following derivations will be built:
12730 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12731 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
12732 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
12733 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
12734 /gnu/store/@dots{}-make-4.1.tar.xz.drv
12735 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
12741 @item --system=@var{system}
12742 @itemx -s @var{system}
12743 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
12744 the system type of the build host. The @command{guix build} command allows
12745 you to repeat this option several times, in which case it builds for all the
12746 specified systems; other commands ignore extraneous @option{-s} options.
12749 The @option{--system} flag is for @emph{native} compilation and must not
12750 be confused with cross-compilation. See @option{--target} below for
12751 information on cross-compilation.
12754 An example use of this is on Linux-based systems, which can emulate
12755 different personalities. For instance, passing
12756 @option{--system=i686-linux} on an @code{x86_64-linux} system or
12757 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
12758 you to build packages in a complete 32-bit environment.
12761 Building for an @code{armhf-linux} system is unconditionally enabled on
12762 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
12763 allow for this functionality, notably the ThunderX.
12766 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
12767 is enabled (@pxref{Virtualization Services,
12768 @code{qemu-binfmt-service-type}}), you can build for any system for
12769 which a QEMU @code{binfmt_misc} handler is installed.
12771 Builds for a system other than that of the machine you are using can
12772 also be offloaded to a remote machine of the right architecture.
12773 @xref{Daemon Offload Setup}, for more information on offloading.
12775 @item --target=@var{triplet}
12776 @cindex cross-compilation
12777 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
12778 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
12779 configuration triplets,, autoconf, Autoconf}).
12781 @item --list-systems
12782 List all the supported systems, that can be passed as an argument to
12785 @item --list-targets
12786 List all the supported targets, that can be passed as an argument to
12789 @anchor{build-check}
12791 @cindex determinism, checking
12792 @cindex reproducibility, checking
12793 Rebuild @var{package-or-derivation}, which are already available in the
12794 store, and raise an error if the build results are not bit-for-bit
12797 This mechanism allows you to check whether previously installed
12798 substitutes are genuine (@pxref{Substitutes}), or whether the build result
12799 of a package is deterministic. @xref{Invoking guix challenge}, for more
12800 background information and tools.
12802 When used in conjunction with @option{--keep-failed}, the differing
12803 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12804 This makes it easy to look for differences between the two results.
12807 @cindex repairing store items
12808 @cindex corruption, recovering from
12809 Attempt to repair the specified store items, if they are corrupt, by
12810 re-downloading or rebuilding them.
12812 This operation is not atomic and thus restricted to @code{root}.
12814 @item --derivations
12816 Return the derivation paths, not the output paths, of the given
12819 @item --root=@var{file}
12820 @itemx -r @var{file}
12821 @cindex GC roots, adding
12822 @cindex garbage collector roots, adding
12823 Make @var{file} a symlink to the result, and register it as a garbage
12826 Consequently, the results of this @command{guix build} invocation are
12827 protected from garbage collection until @var{file} is removed. When
12828 that option is omitted, build results are eligible for garbage
12829 collection as soon as the build completes. @xref{Invoking guix gc}, for
12833 @cindex build logs, access
12834 Return the build log file names or URLs for the given
12835 @var{package-or-derivation}, or raise an error if build logs are
12838 This works regardless of how packages or derivations are specified. For
12839 instance, the following invocations are equivalent:
12842 guix build --log-file $(guix build -d guile)
12843 guix build --log-file $(guix build guile)
12844 guix build --log-file guile
12845 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
12848 If a log is unavailable locally, and unless @option{--no-substitutes} is
12849 passed, the command looks for a corresponding log on one of the
12850 substitute servers (as specified with @option{--substitute-urls}).
12852 So for instance, imagine you want to see the build log of GDB on
12853 @code{aarch64}, but you are actually on an @code{x86_64} machine:
12856 $ guix build --log-file gdb -s aarch64-linux
12857 https://@value{SUBSTITUTE-SERVER-1}/log/@dots{}-gdb-7.10
12860 You can freely access a huge library of build logs!
12863 @node Debugging Build Failures
12864 @subsection Debugging Build Failures
12866 @cindex build failures, debugging
12867 When defining a new package (@pxref{Defining Packages}), you will
12868 probably find yourself spending some time debugging and tweaking the
12869 build until it succeeds. To do that, you need to operate the build
12870 commands yourself in an environment as close as possible to the one the
12873 To that end, the first thing to do is to use the @option{--keep-failed}
12874 or @option{-K} option of @command{guix build}, which will keep the
12875 failed build tree in @file{/tmp} or whatever directory you specified as
12876 @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
12878 From there on, you can @command{cd} to the failed build tree and source
12879 the @file{environment-variables} file, which contains all the
12880 environment variable definitions that were in place when the build
12881 failed. So let's say you're debugging a build failure in package
12882 @code{foo}; a typical session would look like this:
12885 $ guix build foo -K
12886 @dots{} @i{build fails}
12887 $ cd /tmp/guix-build-foo.drv-0
12888 $ source ./environment-variables
12892 Now, you can invoke commands as if you were the daemon (almost) and
12893 troubleshoot your build process.
12895 Sometimes it happens that, for example, a package's tests pass when you
12896 run them manually but they fail when the daemon runs them. This can
12897 happen because the daemon runs builds in containers where, unlike in our
12898 environment above, network access is missing, @file{/bin/sh} does not
12899 exist, etc. (@pxref{Build Environment Setup}).
12901 In such cases, you may need to run inspect the build process from within
12902 a container similar to the one the build daemon creates:
12905 $ guix build -K foo
12907 $ cd /tmp/guix-build-foo.drv-0
12908 $ guix shell --no-grafts -C -D foo strace gdb
12909 [env]# source ./environment-variables
12913 Here, @command{guix shell -C} creates a container and spawns a new
12914 shell in it (@pxref{Invoking guix shell}). The @command{strace gdb}
12915 part adds the @command{strace} and @command{gdb} commands to
12916 the container, which you may find handy while debugging. The
12917 @option{--no-grafts} option makes sure we get the exact same
12918 environment, with ungrafted packages (@pxref{Security Updates}, for more
12921 To get closer to a container like that used by the build daemon, we can
12922 remove @file{/bin/sh}:
12928 (Don't worry, this is harmless: this is all happening in the throw-away
12929 container created by @command{guix shell}.)
12931 The @command{strace} command is probably not in the search path, but we
12935 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
12938 In this way, not only you will have reproduced the environment variables
12939 the daemon uses, you will also be running the build process in a container
12940 similar to the one the daemon uses.
12943 @node Invoking guix edit
12944 @section Invoking @command{guix edit}
12946 @cindex @command{guix edit}
12947 @cindex package definition, editing
12948 So many packages, so many source files! The @command{guix edit} command
12949 facilitates the life of users and packagers by pointing their editor at
12950 the source file containing the definition of the specified packages.
12954 guix edit gcc@@4.9 vim
12958 launches the program specified in the @env{VISUAL} or in the
12959 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
12962 If you are using a Guix Git checkout (@pxref{Building from Git}), or
12963 have created your own packages on @env{GUIX_PACKAGE_PATH}
12964 (@pxref{Package Modules}), you will be able to edit the package
12965 recipes. In other cases, you will be able to examine the read-only recipes
12966 for packages currently in the store.
12968 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
12969 @option{--load-path=@var{directory}} (or in short @option{-L
12970 @var{directory}}) allows you to add @var{directory} to the front of the
12971 package module search path and so make your own packages visible.
12973 @node Invoking guix download
12974 @section Invoking @command{guix download}
12976 @cindex @command{guix download}
12977 @cindex downloading package sources
12978 When writing a package definition, developers typically need to download
12979 a source tarball, compute its SHA256 hash, and write that
12980 hash in the package definition (@pxref{Defining Packages}). The
12981 @command{guix download} tool helps with this task: it downloads a file
12982 from the given URI, adds it to the store, and prints both its file name
12983 in the store and its SHA256 hash.
12985 The fact that the downloaded file is added to the store saves bandwidth:
12986 when the developer eventually tries to build the newly defined package
12987 with @command{guix build}, the source tarball will not have to be
12988 downloaded again because it is already in the store. It is also a
12989 convenient way to temporarily stash files, which may be deleted
12990 eventually (@pxref{Invoking guix gc}).
12992 The @command{guix download} command supports the same URIs as used in
12993 package definitions. In particular, it supports @code{mirror://} URIs.
12994 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
12995 Guile bindings for GnuTLS are available in the user's environment; when
12996 they are not available, an error is raised. @xref{Guile Preparations,
12997 how to install the GnuTLS bindings for Guile,, gnutls-guile,
12998 GnuTLS-Guile}, for more information.
13000 @command{guix download} verifies HTTPS server certificates by loading
13001 the certificates of X.509 authorities from the directory pointed to by
13002 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
13003 Certificates}), unless @option{--no-check-certificate} is used.
13005 The following options are available:
13008 @item --hash=@var{algorithm}
13009 @itemx -H @var{algorithm}
13010 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
13011 hash}, for more information.
13013 @item --format=@var{fmt}
13014 @itemx -f @var{fmt}
13015 Write the hash in the format specified by @var{fmt}. For more
13016 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
13018 @item --no-check-certificate
13019 Do not validate the X.509 certificates of HTTPS servers.
13021 When using this option, you have @emph{absolutely no guarantee} that you
13022 are communicating with the authentic server responsible for the given
13023 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
13025 @item --output=@var{file}
13026 @itemx -o @var{file}
13027 Save the downloaded file to @var{file} instead of adding it to the
13031 @node Invoking guix hash
13032 @section Invoking @command{guix hash}
13034 @cindex @command{guix hash}
13035 The @command{guix hash} command computes the hash of a file.
13036 It is primarily a convenience tool for anyone contributing to the
13037 distribution: it computes the cryptographic hash of one or more files, which can be
13038 used in the definition of a package (@pxref{Defining Packages}).
13040 The general syntax is:
13043 guix hash @var{option} @var{file} ...
13046 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
13047 hash of data read from standard input. @command{guix hash} has the
13052 @item --hash=@var{algorithm}
13053 @itemx -H @var{algorithm}
13054 Compute a hash using the specified @var{algorithm}, @code{sha256} by
13057 @var{algorithm} must be the name of a cryptographic hash algorithm
13058 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
13059 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
13060 Reference Manual}).
13062 @item --format=@var{fmt}
13063 @itemx -f @var{fmt}
13064 Write the hash in the format specified by @var{fmt}.
13066 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
13067 (@code{hex} and @code{hexadecimal} can be used as well).
13069 If the @option{--format} option is not specified, @command{guix hash}
13070 will output the hash in @code{nix-base32}. This representation is used
13071 in the definitions of packages.
13075 The @option{--recursive} option is deprecated in favor of
13076 @option{--serializer=nar} (see below); @option{-r} remains accepted as a
13077 convenient shorthand.
13079 @item --serializer=@var{type}
13080 @itemx -S @var{type}
13081 Compute the hash on @var{file} using @var{type} serialization.
13083 @var{type} may be one of the following:
13087 This is the default: it computes the hash of a file's contents.
13090 Compute the hash of a ``normalized archive'' (or ``nar'') containing
13091 @var{file}, including its children if it is a directory. Some of the
13092 metadata of @var{file} is part of the archive; for instance, when
13093 @var{file} is a regular file, the hash is different depending on whether
13094 @var{file} is executable or not. Metadata such as time stamps have no
13095 impact on the hash (@pxref{Invoking guix archive}, for more info on the
13097 @c FIXME: Replace xref above with xref to an ``Archive'' section when
13101 Compute the hash of the file or directory as a Git ``tree'', following
13102 the same method as the Git version control system.
13105 @item --exclude-vcs
13107 When combined with @option{--recursive}, exclude version control system
13108 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
13111 As an example, here is how you would compute the hash of a Git checkout,
13112 which is useful when using the @code{git-fetch} method (@pxref{origin
13116 $ git clone http://example.org/foo.git
13118 $ guix hash -x --serializer=nar .
13122 @node Invoking guix import
13123 @section Invoking @command{guix import}
13125 @cindex importing packages
13126 @cindex package import
13127 @cindex package conversion
13128 @cindex Invoking @command{guix import}
13129 The @command{guix import} command is useful for people who would like to
13130 add a package to the distribution with as little work as
13131 possible---a legitimate demand. The command knows of a few
13132 repositories from which it can ``import'' package metadata. The result
13133 is a package definition, or a template thereof, in the format we know
13134 (@pxref{Defining Packages}).
13136 The general syntax is:
13139 guix import @var{importer} @var{options}@dots{}
13142 @var{importer} specifies the source from which to import package
13143 metadata, and @var{options} specifies a package identifier and other
13144 options specific to @var{importer}.
13146 Some of the importers rely on the ability to run the @command{gpgv} command.
13147 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
13150 Currently, the available ``importers'' are:
13154 Import metadata for the given GNU package. This provides a template
13155 for the latest version of that GNU package, including the hash of its
13156 source tarball, and its canonical synopsis and description.
13158 Additional information such as the package dependencies and its
13159 license needs to be figured out manually.
13161 For example, the following command returns a package definition for
13165 guix import gnu hello
13168 Specific command-line options are:
13171 @item --key-download=@var{policy}
13172 As for @command{guix refresh}, specify the policy to handle missing
13173 OpenPGP keys when verifying the package signature. @xref{Invoking guix
13174 refresh, @option{--key-download}}.
13179 Import metadata from the @uref{https://pypi.python.org/, Python Package
13180 Index}. Information is taken from the JSON-formatted description
13181 available at @code{pypi.python.org} and usually includes all the relevant
13182 information, including package dependencies. For maximum efficiency, it
13183 is recommended to install the @command{unzip} utility, so that the
13184 importer can unzip Python wheels and gather data from them.
13186 The command below imports metadata for the latest version of the
13187 @code{itsdangerous} Python package:
13190 guix import pypi itsdangerous
13193 You can also ask for a specific version:
13196 guix import pypi itsdangerous@@1.1.0
13202 Traverse the dependency graph of the given upstream package recursively
13203 and generate package expressions for all those packages that are not yet
13209 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
13210 is taken from the JSON-formatted description available at
13211 @code{rubygems.org} and includes most relevant information, including
13212 runtime dependencies. There are some caveats, however. The metadata
13213 doesn't distinguish between synopses and descriptions, so the same string
13214 is used for both fields. Additionally, the details of non-Ruby
13215 dependencies required to build native extensions is unavailable and left
13216 as an exercise to the packager.
13218 The command below imports metadata for the @code{rails} Ruby package:
13221 guix import gem rails
13224 You can also ask for a specific version:
13227 guix import gem @@7.0.4
13233 Traverse the dependency graph of the given upstream package recursively
13234 and generate package expressions for all those packages that are not yet
13241 Import metadata from @uref{https://content.minetest.net, ContentDB}.
13242 Information is taken from the JSON-formatted metadata provided through
13243 @uref{https://content.minetest.net/help/api/, ContentDB's API} and
13244 includes most relevant information, including dependencies. There are
13245 some caveats, however. The license information is often incomplete.
13246 The commit hash is sometimes missing. The descriptions are in the
13247 Markdown format, but Guix uses Texinfo instead. Texture packs and
13248 subgames are unsupported.
13250 The command below imports metadata for the Mesecons mod by Jeija:
13253 guix import minetest Jeija/mesecons
13256 The author name can also be left out:
13259 guix import minetest mesecons
13265 Traverse the dependency graph of the given upstream package recursively
13266 and generate package expressions for all those packages that are not yet
13272 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
13273 Information is taken from the JSON-formatted metadata provided through
13274 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
13275 relevant information, such as module dependencies. License information
13276 should be checked closely. If Perl is available in the store, then the
13277 @code{corelist} utility will be used to filter core modules out of the
13278 list of dependencies.
13280 The command command below imports metadata for the Acme::Boolean Perl
13284 guix import cpan Acme::Boolean
13289 @cindex Bioconductor
13290 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
13291 central repository for the @uref{https://r-project.org, GNU@tie{}R
13292 statistical and graphical environment}.
13294 Information is extracted from the @file{DESCRIPTION} file of the package.
13296 The command command below imports metadata for the Cairo R package:
13299 guix import cran Cairo
13302 You can also ask for a specific version:
13305 guix import cran rasterVis@@0.50.3
13308 When @option{--recursive} is added, the importer will traverse the
13309 dependency graph of the given upstream package recursively and generate
13310 package expressions for all those packages that are not yet in Guix.
13312 When @option{--style=specification} is added, the importer will generate
13313 package definitions whose inputs are package specifications instead of
13314 references to package variables. This is useful when generated package
13315 definitions are to be appended to existing user modules, as the list of
13316 used package modules need not be changed. The default is
13317 @option{--style=variable}.
13319 When @option{--archive=bioconductor} is added, metadata is imported from
13320 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
13321 packages for the analysis and comprehension of high-throughput
13322 genomic data in bioinformatics.
13324 Information is extracted from the @file{DESCRIPTION} file contained in the
13327 The command below imports metadata for the GenomicRanges R package:
13330 guix import cran --archive=bioconductor GenomicRanges
13333 Finally, you can also import R packages that have not yet been published on
13334 CRAN or Bioconductor as long as they are in a git repository. Use
13335 @option{--archive=git} followed by the URL of the git repository:
13338 guix import cran --archive=git https://github.com/immunogenomics/harmony
13344 Import TeX package information from the TeX Live package database for
13345 TeX packages that are part of the @uref{https://www.tug.org/texlive/,
13346 TeX Live distribution}.
13348 Information about the package is obtained from the TeX Live package
13349 database, a plain text file that is included in the @code{texlive-bin}
13350 package. The source code is downloaded from possibly multiple locations
13351 in the SVN repository of the Tex Live project.
13353 The command command below imports metadata for the @code{fontspec}
13357 guix import texlive fontspec
13361 @cindex JSON, import
13362 Import package metadata from a local JSON file. Consider the following
13363 example package definition in JSON format:
13369 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
13370 "build-system": "gnu",
13371 "home-page": "https://www.gnu.org/software/hello/",
13372 "synopsis": "Hello, GNU world: An example GNU package",
13373 "description": "GNU Hello prints a greeting.",
13374 "license": "GPL-3.0+",
13375 "native-inputs": ["gettext"]
13379 The field names are the same as for the @code{<package>} record
13380 (@xref{Defining Packages}). References to other packages are provided
13381 as JSON lists of quoted package specification strings such as
13382 @code{guile} or @code{guile@@2.0}.
13384 The importer also supports a more explicit source definition using the
13385 common fields for @code{<origin>} records:
13391 "method": "url-fetch",
13392 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
13394 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
13401 The command below reads metadata from the JSON file @code{hello.json}
13402 and outputs a package expression:
13405 guix import json hello.json
13410 Import metadata from the Haskell community's central package archive
13411 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
13412 Cabal files and includes all the relevant information, including package
13415 Specific command-line options are:
13420 Read a Cabal file from standard input.
13421 @item --no-test-dependencies
13423 Do not include dependencies required only by the test suites.
13424 @item --cabal-environment=@var{alist}
13425 @itemx -e @var{alist}
13426 @var{alist} is a Scheme alist defining the environment in which the
13427 Cabal conditionals are evaluated. The accepted keys are: @code{os},
13428 @code{arch}, @code{impl} and a string representing the name of a flag.
13429 The value associated with a flag has to be either the symbol
13430 @code{true} or @code{false}. The value associated with other keys
13431 has to conform to the Cabal file format definition. The default value
13432 associated with the keys @code{os}, @code{arch} and @code{impl} is
13433 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
13436 Traverse the dependency graph of the given upstream package recursively
13437 and generate package expressions for all those packages that are not yet
13441 The command below imports metadata for the latest version of the
13442 HTTP Haskell package without including test dependencies and
13443 specifying the value of the flag @samp{network-uri} as @code{false}:
13446 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
13449 A specific package version may optionally be specified by following the
13450 package name by an at-sign and a version number as in the following example:
13453 guix import hackage mtl@@2.1.3.1
13458 The @code{stackage} importer is a wrapper around the @code{hackage} one.
13459 It takes a package name, looks up the package version included in a
13460 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
13461 release and uses the @code{hackage} importer to retrieve its metadata.
13462 Note that it is up to you to select an LTS release compatible with the
13463 GHC compiler used by Guix.
13465 Specific command-line options are:
13468 @item --no-test-dependencies
13470 Do not include dependencies required only by the test suites.
13471 @item --lts-version=@var{version}
13472 @itemx -l @var{version}
13473 @var{version} is the desired LTS release version. If omitted the latest
13477 Traverse the dependency graph of the given upstream package recursively
13478 and generate package expressions for all those packages that are not yet
13482 The command below imports metadata for the HTTP Haskell package
13483 included in the LTS Stackage release version 7.18:
13486 guix import stackage --lts-version=7.18 HTTP
13491 Import metadata from an Emacs Lisp Package Archive (ELPA) package
13492 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
13494 Specific command-line options are:
13497 @item --archive=@var{repo}
13498 @itemx -a @var{repo}
13499 @var{repo} identifies the archive repository from which to retrieve the
13500 information. Currently the supported repositories and their identifiers
13504 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
13505 identifier. This is the default.
13507 Packages from @code{elpa.gnu.org} are signed with one of the keys
13508 contained in the GnuPG keyring at
13509 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
13510 @code{emacs} package (@pxref{Package Installation, ELPA package
13511 signatures,, emacs, The GNU Emacs Manual}).
13514 @uref{https://elpa.nongnu.org/nongnu/, NonGNU}, selected by the
13515 @code{nongnu} identifier.
13518 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
13519 @code{melpa-stable} identifier.
13522 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
13528 Traverse the dependency graph of the given upstream package recursively
13529 and generate package expressions for all those packages that are not yet
13535 Import metadata from the crates.io Rust package repository
13536 @uref{https://crates.io, crates.io}, as in this example:
13539 guix import crate blake2-rfc
13542 The crate importer also allows you to specify a version string:
13545 guix import crate constant-time-eq@@0.1.0
13548 Additional options include:
13553 Traverse the dependency graph of the given upstream package recursively
13554 and generate package expressions for all those packages that are not yet
13560 Import metadata from the Elm package repository
13561 @uref{https://package.elm-lang.org, package.elm-lang.org}, as in this example:
13564 guix import elm elm-explorations/webgl
13567 The Elm importer also allows you to specify a version string:
13570 guix import elm elm-explorations/webgl@@1.1.3
13573 Additional options include:
13578 Traverse the dependency graph of the given upstream package recursively
13579 and generate package expressions for all those packages that are not yet
13586 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
13587 repository used by the OCaml community.
13589 Additional options include:
13594 Traverse the dependency graph of the given upstream package recursively
13595 and generate package expressions for all those packages that are not yet
13598 By default, packages are searched in the official OPAM repository. This
13599 option, which can be used more than once, lets you add other repositories
13600 which will be searched for packages. It accepts as valid arguments:
13603 @item the name of a known repository - can be one of @code{opam},
13604 @code{coq} (equivalent to @code{coq-released}),
13605 @code{coq-core-dev}, @code{coq-extra-dev} or @code{grew}.
13606 @item the URL of a repository as expected by the
13607 @code{opam repository add} command (for instance, the URL equivalent
13608 of the above @code{opam} name would be
13609 @uref{https://opam.ocaml.org}).
13610 @item the path to a local copy of a repository (a directory containing a
13611 @file{packages/} sub-directory).
13614 Repositories are assumed to be passed to this option by order of
13615 preference. The additional repositories will not replace the default
13616 @code{opam} repository, which is always kept as a fallback.
13618 Also, please note that versions are not compared across repositories.
13619 The first repository (from left to right) that has at least one version
13620 of a given package will prevail over any others, and the version
13621 imported will be the latest one found @emph{in this repository only}.
13627 Import metadata for a Go module using
13628 @uref{https://proxy.golang.org, proxy.golang.org}.
13631 guix import go gopkg.in/yaml.v2
13634 It is possible to use a package specification with a @code{@@VERSION}
13635 suffix to import a specific version.
13637 Additional options include:
13642 Traverse the dependency graph of the given upstream package recursively
13643 and generate package expressions for all those packages that are not yet
13645 @item --pin-versions
13646 When using this option, the importer preserves the exact versions of the
13647 Go modules dependencies instead of using their latest available
13648 versions. This can be useful when attempting to import packages that
13649 recursively depend on former versions of themselves to build. When
13650 using this mode, the symbol of the package is made by appending the
13651 version to its name, so that multiple versions of the same package can
13657 Import metadata for @uref{https://wiki.call-cc.org/eggs, CHICKEN eggs}.
13658 The information is taken from @file{PACKAGE.egg} files found in the
13659 @uref{git://code.call-cc.org/eggs-5-all, eggs-5-all} Git
13660 repository. However, it does not provide all the information that we
13661 need, there is no ``description'' field, and the licenses used are not
13662 always precise (BSD is often used instead of BSD-N).
13665 guix import egg sourcehut
13668 You can also ask for a specific version:
13671 guix import egg arrays@@1.0
13674 Additional options include:
13678 Traverse the dependency graph of the given upstream package recursively
13679 and generate package expressions for all those packages that are not yet
13685 Import metadata from the hex.pm Erlang and Elixir package repository
13686 @uref{https://hex.pm, hex.pm}, as in this example:
13689 guix import hexpm stun
13692 The importer tries to determine the build system used by the package.
13694 The hexpm importer also allows you to specify a version string:
13697 guix import hexpm cf@@0.3.0
13700 Additional options include:
13705 Traverse the dependency graph of the given upstream package recursively
13706 and generate package expressions for all those packages that are not yet
13711 The structure of the @command{guix import} code is modular. It would be
13712 useful to have more importers for other package formats, and your help
13713 is welcome here (@pxref{Contributing}).
13715 @node Invoking guix refresh
13716 @section Invoking @command{guix refresh}
13718 @cindex @command {guix refresh}
13719 The primary audience of the @command{guix refresh} command is packagers.
13720 As a user, you may be interested in the @option{--with-latest} option,
13721 which can bring you package update superpowers built upon @command{guix
13722 refresh} (@pxref{Package Transformation Options,
13723 @option{--with-latest}}). By default, @command{guix refresh} reports
13724 any packages provided by the distribution that are outdated compared to
13725 the latest upstream version, like this:
13729 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
13730 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
13733 Alternatively, one can specify packages to consider, in which case a
13734 warning is emitted for packages that lack an updater:
13737 $ guix refresh coreutils guile guile-ssh
13738 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
13739 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
13742 @command{guix refresh} browses the upstream repository of each package and determines
13743 the highest version number of the releases therein. The command
13744 knows how to update specific types of packages: GNU packages, ELPA
13745 packages, etc.---see the documentation for @option{--type} below. There
13746 are many packages, though, for which it lacks a method to determine
13747 whether a new upstream release is available. However, the mechanism is
13748 extensible, so feel free to get in touch with us to add a new method!
13753 Consider the packages specified, and all the packages upon which they depend.
13756 $ guix refresh --recursive coreutils
13757 gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
13758 gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
13759 gnu/packages/xml.scm:68:2: warning: no updater for expat
13760 gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
13766 Sometimes the upstream name differs from the package name used in Guix,
13767 and @command{guix refresh} needs a little help. Most updaters honor the
13768 @code{upstream-name} property in package definitions, which can be used
13772 (define-public network-manager
13774 (name "network-manager")
13776 (properties '((upstream-name . "NetworkManager")))))
13779 When passed @option{--update}, it modifies distribution source files to
13780 update the version numbers and source tarball hashes of those package
13781 recipes (@pxref{Defining Packages}). This is achieved by downloading
13782 each package's latest source tarball and its associated OpenPGP
13783 signature, authenticating the downloaded tarball against its signature
13784 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
13785 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
13788 key used to sign the tarball is missing from the user's keyring, an
13789 attempt is made to automatically retrieve it from a public key server;
13790 when this is successful, the key is added to the user's keyring; otherwise,
13791 @command{guix refresh} reports an error.
13793 The following options are supported:
13797 @item --expression=@var{expr}
13798 @itemx -e @var{expr}
13799 Consider the package @var{expr} evaluates to.
13801 This is useful to precisely refer to a package, as in this example:
13804 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
13807 This command lists the dependents of the ``final'' libc (essentially all
13812 Update distribution source files (package recipes) in place. This is
13813 usually run from a checkout of the Guix source tree (@pxref{Running
13814 Guix Before It Is Installed}):
13817 $ ./pre-inst-env guix refresh -s non-core -u
13820 @xref{Defining Packages}, for more information on package definitions.
13822 @item --select=[@var{subset}]
13823 @itemx -s @var{subset}
13824 Select all the packages in @var{subset}, one of @code{core} or
13827 The @code{core} subset refers to all the packages at the core of the
13828 distribution---i.e., packages that are used to build ``everything
13829 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
13830 changing one of these packages in the distribution entails a rebuild of
13831 all the others. Thus, such updates are an inconvenience to users in
13832 terms of build time or bandwidth used to achieve the upgrade.
13834 The @code{non-core} subset refers to the remaining packages. It is
13835 typically useful in cases where an update of the core packages would be
13838 @item --manifest=@var{file}
13839 @itemx -m @var{file}
13840 Select all the packages from the manifest in @var{file}. This is useful to
13841 check if any packages of the user manifest can be updated.
13843 @item --type=@var{updater}
13844 @itemx -t @var{updater}
13845 Select only packages handled by @var{updater} (may be a comma-separated
13846 list of updaters). Currently, @var{updater} may be one of:
13850 the updater for GNU packages;
13852 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
13854 the updater for packages hosted at @uref{https://sourceforge.net, SourceForge};
13856 the updater for GNOME packages;
13858 the updater for KDE packages;
13860 the updater for X.org packages;
13862 the updater for packages hosted on kernel.org;
13864 the updater for @uref{https://wiki.call-cc.org/eggs/, Egg} packages;
13866 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
13868 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
13870 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
13872 the updater for @uref{https://www.cpan.org/, CPAN} packages;
13874 the updater for @uref{https://pypi.python.org, PyPI} packages.
13876 the updater for @uref{https://rubygems.org, RubyGems} packages.
13878 the updater for @uref{https://github.com, GitHub} packages.
13880 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
13882 the updater for @uref{https://www.stackage.org, Stackage} packages.
13884 the updater for @uref{https://crates.io, Crates} packages.
13886 the updater for @uref{https://launchpad.net, Launchpad} packages.
13888 a generic updater that crawls the HTML page where the source tarball of
13889 the package is hosted, when applicable.
13892 a generic updater for packages hosted on Git repositories. It tries to
13893 be smart about parsing Git tag names, but if it is not able to parse the
13894 tag name and compare tags correctly, users can define the following
13895 properties for a package.
13898 @item @code{release-tag-prefix}: a regular expression for matching a prefix of
13901 @item @code{release-tag-suffix}: a regular expression for matching a suffix of
13904 @item @code{release-tag-version-delimiter}: a string used as the delimiter in
13905 the tag name for separating the numbers of the version.
13907 @item @code{accept-pre-releases}: by default, the updater will ignore
13908 pre-releases; to make it also look for pre-releases, set the this
13909 property to @code{#t}.
13918 '((release-tag-prefix . "^release0-")
13919 (release-tag-suffix . "[a-z]?$")
13920 (release-tag-version-delimiter . ":"))))
13926 For instance, the following command only checks for updates of Emacs
13927 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
13930 $ guix refresh --type=elpa,cran
13931 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
13932 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
13935 @item --list-updaters
13936 List available updaters and exit (see @option{--type} above).
13938 For each updater, display the fraction of packages it covers; at the
13939 end, display the fraction of packages covered by all these updaters.
13942 In addition, @command{guix refresh} can be passed one or more package
13943 names, as in this example:
13946 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
13950 The command above specifically updates the @code{emacs} and
13951 @code{idutils} packages. The @option{--select} option would have no
13952 effect in this case. You might also want to update definitions that
13953 correspond to the packages installed in your profile:
13956 $ ./pre-inst-env guix refresh -u \
13957 $(guix package --list-installed | cut -f1)
13960 When considering whether to upgrade a package, it is sometimes
13961 convenient to know which packages would be affected by the upgrade and
13962 should be checked for compatibility. For this the following option may
13963 be used when passing @command{guix refresh} one or more package names:
13967 @item --list-dependent
13969 List top-level dependent packages that would need to be rebuilt as a
13970 result of upgrading one or more packages.
13972 @xref{Invoking guix graph, the @code{reverse-package} type of
13973 @command{guix graph}}, for information on how to visualize the list of
13974 dependents of a package.
13978 Be aware that the @option{--list-dependent} option only
13979 @emph{approximates} the rebuilds that would be required as a result of
13980 an upgrade. More rebuilds might be required under some circumstances.
13983 $ guix refresh --list-dependent flex
13984 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
13985 hop@@2.4.0 emacs-geiser@@0.13 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
13988 The command above lists a set of packages that could be built to check
13989 for compatibility with an upgraded @code{flex} package.
13993 @item --list-transitive
13994 List all the packages which one or more packages depend upon.
13997 $ guix refresh --list-transitive flex
13998 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
13999 bison@@3.0.5 indent@@2.2.10 tar@@1.30 gzip@@1.9 bzip2@@1.0.6 xz@@5.2.4 file@@5.33 @dots{}
14004 The command above lists a set of packages which, when changed, would cause
14005 @code{flex} to be rebuilt.
14007 The following options can be used to customize GnuPG operation:
14011 @item --gpg=@var{command}
14012 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
14013 for in @code{$PATH}.
14015 @item --keyring=@var{file}
14016 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
14017 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
14018 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
14019 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
14020 information on a tool to manipulate keybox files).
14022 When this option is omitted, @command{guix refresh} uses
14023 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
14024 signing keys. OpenPGP signatures are checked against keys from this keyring;
14025 missing keys are downloaded to this keyring as well (see
14026 @option{--key-download} below).
14028 You can export keys from your default GPG keyring into a keybox file using
14029 commands like this one:
14032 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
14035 Likewise, you can fetch keys to a specific keybox file like this:
14038 gpg --no-default-keyring --keyring mykeyring.kbx \
14039 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
14042 @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
14043 Privacy Guard}, for more information on GPG's @option{--keyring} option.
14045 @item --key-download=@var{policy}
14046 Handle missing OpenPGP keys according to @var{policy}, which may be one
14051 Always download missing OpenPGP keys from the key server, and add them
14052 to the user's GnuPG keyring.
14055 Never try to download missing OpenPGP keys. Instead just bail out.
14058 When a package signed with an unknown OpenPGP key is encountered, ask
14059 the user whether to download it or not. This is the default behavior.
14062 @item --key-server=@var{host}
14063 Use @var{host} as the OpenPGP key server when importing a public key.
14065 @item --load-path=@var{directory}
14066 @itemx -L @var{directory}
14067 Add @var{directory} to the front of the package module search path
14068 (@pxref{Package Modules}).
14070 This allows users to define their own packages and make them visible to
14071 the command-line tools.
14075 The @code{github} updater uses the
14076 @uref{https://developer.github.com/v3/, GitHub API} to query for new
14077 releases. When used repeatedly e.g.@: when refreshing all packages,
14078 GitHub will eventually refuse to answer any further API requests. By
14079 default 60 API requests per hour are allowed, and a full refresh on all
14080 GitHub packages in Guix requires more than this. Authentication with
14081 GitHub through the use of an API token alleviates these limits. To use
14082 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
14083 token procured from @uref{https://github.com/settings/tokens} or
14087 @node Invoking guix style
14088 @section Invoking @command{guix style}
14090 The @command{guix style} command helps users and packagers alike style
14091 their package definitions and configuration files according to the
14092 latest fashionable trends. It can either reformat whole files, with the
14093 @option{--whole-file} option, or apply specific @dfn{styling rules} to
14094 individual package definitions. The command currently provides the
14095 following styling rules:
14099 formatting package definitions according to the project's conventions
14100 (@pxref{Formatting Code});
14103 rewriting package inputs to the ``new style'', as explained below.
14106 The way package inputs are written is going through a transition
14107 (@pxref{package Reference}, for more on package inputs). Until version
14108 1.3.0, package inputs were written using the ``old style'', where each
14109 input was given an explicit label, most of the time the package name:
14114 ;; The "old style" (deprecated).
14115 (inputs `(("libunistring" ,libunistring)
14116 ("libffi" ,libffi))))
14119 Today, the old style is deprecated and the preferred style looks like
14125 ;; The "new style".
14126 (inputs (list libunistring libffi)))
14129 Likewise, uses of @code{alist-delete} and friends to manipulate inputs
14130 is now deprecated in favor of @code{modify-inputs} (@pxref{Defining
14131 Package Variants}, for more info on @code{modify-inputs}).
14133 In the vast majority of cases, this is a purely mechanical change on the
14134 surface syntax that does not even incur a package rebuild. Running
14135 @command{guix style -S inputs} can do that for you, whether you're working on
14136 packages in Guix proper or in an external channel.
14138 The general syntax is:
14141 guix style [@var{options}] @var{package}@dots{}
14144 This causes @command{guix style} to analyze and rewrite the definition
14145 of @var{package}@dots{} or, when @var{package} is omitted, of @emph{all}
14146 the packages. The @option{--styling} or @option{-S} option allows you
14147 to select the style rule, the default rule being @code{format}---see
14150 To reformat entire source files, the syntax is:
14153 guix style --whole-file @var{file}@dots{}
14156 The available options are listed below.
14161 Show source file locations that would be edited but do not modify them.
14165 Reformat the given files in their entirety. In that case, subsequent
14166 arguments are interpreted as file names (rather than package names), and
14167 the @option{--styling} option has no effect.
14169 As an example, here is how you might reformat your operating system
14170 configuration (you need write permissions for the file):
14173 guix style -f /etc/config.scm
14176 @item --styling=@var{rule}
14177 @itemx -S @var{rule}
14178 Apply @var{rule}, one of the following styling rules:
14182 Format the given package definition(s)---this is the default styling
14183 rule. For example, a packager running Guix on a checkout
14184 (@pxref{Running Guix Before It Is Installed}) might want to reformat the
14185 definition of the Coreutils package like so:
14188 ./pre-inst-env guix style coreutils
14192 Rewrite package inputs to the ``new style'', as described above. This
14193 is how you would rewrite inputs of package @code{whatnot} in your own
14197 guix style -L ~/my/channel -S inputs whatnot
14200 Rewriting is done in a conservative way: preserving comments and bailing
14201 out if it cannot make sense of the code that appears in an inputs field.
14202 The @option{--input-simplification} option described below provides
14203 fine-grain control over when inputs should be simplified.
14206 @item --list-stylings
14208 List and describe the available styling rules and exit.
14210 @item --load-path=@var{directory}
14211 @itemx -L @var{directory}
14212 Add @var{directory} to the front of the package module search path
14213 (@pxref{Package Modules}).
14215 @item --expression=@var{expr}
14216 @itemx -e @var{expr}
14217 Style the package @var{expr} evaluates to.
14219 For example, running:
14222 guix style -e '(@@ (gnu packages gcc) gcc-5)'
14225 styles the @code{gcc-5} package definition.
14227 @item --input-simplification=@var{policy}
14228 When using the @code{inputs} styling rule, with @samp{-S inputs}, this
14229 option specifies the package input simplification policy for cases where
14230 an input label does not match the corresponding package name.
14231 @var{policy} may be one of the following:
14235 Simplify inputs only when the change is ``silent'', meaning that the
14236 package does not need to be rebuilt (its derivation is unchanged).
14239 Simplify inputs only when that is ``safe'' to do: the package might need
14240 to be rebuilt, but the change is known to have no observable effect.
14243 Simplify inputs even when input labels do not match package names, and
14244 even if that might have an observable effect.
14247 The default is @code{silent}, meaning that input simplifications do not
14248 trigger any package rebuild.
14251 @node Invoking guix lint
14252 @section Invoking @command{guix lint}
14254 @cindex @command{guix lint}
14255 @cindex package, checking for errors
14256 The @command{guix lint} command is meant to help package developers avoid
14257 common errors and use a consistent style. It runs a number of checks on
14258 a given set of packages in order to find common mistakes in their
14259 definitions. Available @dfn{checkers} include (see
14260 @option{--list-checkers} for a complete list):
14265 Validate certain typographical and stylistic rules about package
14266 descriptions and synopses.
14268 @item inputs-should-be-native
14269 Identify inputs that should most likely be native inputs.
14275 @itemx source-file-name
14276 Probe @code{home-page} and @code{source} URLs and report those that are
14277 invalid. Suggest a @code{mirror://} URL when applicable. If the
14278 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
14279 URL@. Check that the source file name is meaningful, e.g.@: is not just a
14280 version number or ``git-checkout'', without a declared @code{file-name}
14281 (@pxref{origin Reference}).
14283 @item source-unstable-tarball
14284 Parse the @code{source} URL to determine if a tarball from GitHub is
14285 autogenerated or if it is a release tarball. Unfortunately GitHub's
14286 autogenerated tarballs are sometimes regenerated.
14289 Check that the derivation of the given packages can be successfully
14290 computed for all the supported systems (@pxref{Derivations}).
14292 @item profile-collisions
14293 Check whether installing the given packages in a profile would lead to
14294 collisions. Collisions occur when several packages with the same name
14295 but a different version or a different store file name are propagated.
14296 @xref{package Reference, @code{propagated-inputs}}, for more information
14297 on propagated inputs.
14300 @cindex Software Heritage, source code archive
14301 @cindex archival of source code, Software Heritage
14302 Checks whether the package's source code is archived at
14303 @uref{https://www.softwareheritage.org, Software Heritage}.
14305 When the source code that is not archived comes from a version-control system
14306 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
14307 ``save'' request so that it eventually archives it. This ensures that the
14308 source will remain available in the long term, and that Guix can fall back to
14309 Software Heritage should the source code disappear from its original host.
14310 The status of recent ``save'' requests can be
14311 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
14313 When source code is a tarball obtained with @code{url-fetch}, simply print a
14314 message when it is not archived. As of this writing, Software Heritage does
14315 not allow requests to save arbitrary tarballs; we are working on ways to
14316 ensure that non-VCS source code is also archived.
14319 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
14320 request rate per IP address}. When the limit is reached, @command{guix lint}
14321 prints a message and the @code{archival} checker stops doing anything until
14322 that limit has been reset.
14325 @cindex security vulnerabilities
14326 @cindex CVE, Common Vulnerabilities and Exposures
14327 Report known vulnerabilities found in the Common Vulnerabilities and
14328 Exposures (CVE) databases of the current and past year
14329 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
14332 To view information about a particular vulnerability, visit pages such as:
14336 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
14338 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
14342 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
14343 @code{CVE-2015-7554}.
14345 Package developers can specify in package recipes the
14346 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
14347 name and version of the package when they differ from the name or version
14348 that Guix uses, as in this example:
14354 ;; CPE calls this package "grub2".
14355 (properties '((cpe-name . "grub2")
14356 (cpe-version . "2.3"))))
14359 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
14360 Some entries in the CVE database do not specify which version of a
14361 package they apply to, and would thus ``stick around'' forever. Package
14362 developers who found CVE alerts and verified they can be ignored can
14363 declare them as in this example:
14369 ;; These CVEs no longer apply and can be safely ignored.
14370 (properties `((lint-hidden-cve . ("CVE-2011-0433"
14373 "CVE-2011-5244")))))
14377 Warn about obvious source code formatting issues: trailing white space,
14378 use of tabulations, etc.
14381 Report old-style input labels that do not match the name of the
14382 corresponding package. This aims to help migrate from the ``old input
14383 style''. @xref{package Reference}, for more information on package
14384 inputs and input styles. @xref{Invoking guix style}, on how to migrate
14388 The general syntax is:
14391 guix lint @var{options} @var{package}@dots{}
14394 If no package is given on the command line, then all packages are checked.
14395 The @var{options} may be zero or more of the following:
14398 @item --list-checkers
14400 List and describe all the available checkers that will be run on packages
14405 Only enable the checkers specified in a comma-separated list using the
14406 names returned by @option{--list-checkers}.
14410 Only disable the checkers specified in a comma-separated list using the
14411 names returned by @option{--list-checkers}.
14413 @item --expression=@var{expr}
14414 @itemx -e @var{expr}
14415 Consider the package @var{expr} evaluates to.
14417 This is useful to unambiguously designate packages, as in this example:
14420 guix lint -c archival -e '(@@ (gnu packages guile) guile-3.0)'
14425 Only enable the checkers that do not depend on Internet access.
14427 @item --load-path=@var{directory}
14428 @itemx -L @var{directory}
14429 Add @var{directory} to the front of the package module search path
14430 (@pxref{Package Modules}).
14432 This allows users to define their own packages and make them visible to
14433 the command-line tools.
14437 @node Invoking guix size
14438 @section Invoking @command{guix size}
14441 @cindex package size
14443 @cindex @command{guix size}
14444 The @command{guix size} command helps package developers profile the
14445 disk usage of packages. It is easy to overlook the impact of an
14446 additional dependency added to a package, or the impact of using a
14447 single output for a package that could easily be split (@pxref{Packages
14448 with Multiple Outputs}). Such are the typical issues that
14449 @command{guix size} can highlight.
14451 The command can be passed one or more package specifications
14452 such as @code{gcc@@4.8}
14453 or @code{guile:debug}, or a file name in the store. Consider this
14457 $ guix size coreutils
14458 store item total self
14459 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
14460 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
14461 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
14462 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
14463 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
14464 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
14465 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
14466 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
14471 The store items listed here constitute the @dfn{transitive closure} of
14472 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
14473 would be returned by:
14476 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
14479 Here the output shows three columns next to store items. The first column,
14480 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
14481 the store item---that is, its own size plus the size of all its
14482 dependencies. The next column, labeled ``self'', shows the size of the
14483 item itself. The last column shows the ratio of the size of the item
14484 itself to the space occupied by all the items listed here.
14486 In this example, we see that the closure of Coreutils weighs in at
14487 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
14488 libraries. (That libc and GCC's libraries represent a large fraction of
14489 the closure is not a problem @i{per se} because they are always available
14490 on the system anyway.)
14492 Since the command also accepts store file names, assessing the size of
14493 a build result is straightforward:
14496 guix size $(guix system build config.scm)
14499 When the package(s) passed to @command{guix size} are available in the
14500 store@footnote{More precisely, @command{guix size} looks for the
14501 @emph{ungrafted} variant of the given package(s), as returned by
14502 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
14503 for information on grafts.}, @command{guix size} queries the daemon to determine its
14504 dependencies, and measures its size in the store, similar to @command{du
14505 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
14508 When the given packages are @emph{not} in the store, @command{guix size}
14509 reports information based on the available substitutes
14510 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
14511 store items that are not even on disk, only available remotely.
14513 You can also specify several package names:
14516 $ guix size coreutils grep sed bash
14517 store item total self
14518 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
14519 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
14520 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
14521 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
14527 In this example we see that the combination of the four packages takes
14528 102.3@tie{}MiB in total, which is much less than the sum of each closure
14529 since they have a lot of dependencies in common.
14531 When looking at the profile returned by @command{guix size}, you may
14532 find yourself wondering why a given package shows up in the profile at
14533 all. To understand it, you can use @command{guix graph --path -t
14534 references} to display the shortest path between the two packages
14535 (@pxref{Invoking guix graph}).
14537 The available options are:
14541 @item --substitute-urls=@var{urls}
14542 Use substitute information from @var{urls}.
14543 @xref{client-substitute-urls, the same option for @code{guix build}}.
14545 @item --sort=@var{key}
14546 Sort lines according to @var{key}, one of the following options:
14550 the size of each item (the default);
14552 the total size of the item's closure.
14555 @item --map-file=@var{file}
14556 Write a graphical map of disk usage in PNG format to @var{file}.
14558 For the example above, the map looks like this:
14560 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
14561 produced by @command{guix size}}
14563 This option requires that
14564 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
14565 installed and visible in Guile's module search path. When that is not
14566 the case, @command{guix size} fails as it tries to load it.
14568 @item --system=@var{system}
14569 @itemx -s @var{system}
14570 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
14572 @item --load-path=@var{directory}
14573 @itemx -L @var{directory}
14574 Add @var{directory} to the front of the package module search path
14575 (@pxref{Package Modules}).
14577 This allows users to define their own packages and make them visible to
14578 the command-line tools.
14581 @node Invoking guix graph
14582 @section Invoking @command{guix graph}
14585 @cindex @command{guix graph}
14586 @cindex package dependencies
14587 Packages and their dependencies form a @dfn{graph}, specifically a
14588 directed acyclic graph (DAG). It can quickly become difficult to have a
14589 mental model of the package DAG, so the @command{guix graph} command
14590 provides a visual representation of the DAG@. By default,
14591 @command{guix graph} emits a DAG representation in the input format of
14592 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
14593 directly to the @command{dot} command of Graphviz. It can also emit an
14594 HTML page with embedded JavaScript code to display a ``chord diagram''
14595 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
14596 emit Cypher queries to construct a graph in a graph database supporting
14597 the @uref{https://www.opencypher.org/, openCypher} query language. With
14598 @option{--path}, it simply displays the shortest path between two
14599 packages. The general syntax is:
14602 guix graph @var{options} @var{package}@dots{}
14605 For example, the following command generates a PDF file representing the
14606 package DAG for the GNU@tie{}Core Utilities, showing its build-time
14610 guix graph coreutils | dot -Tpdf > dag.pdf
14613 The output looks like this:
14615 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
14617 Nice little graph, no?
14619 You may find it more pleasant to navigate the graph interactively with
14620 @command{xdot} (from the @code{xdot} package):
14623 guix graph coreutils | xdot -
14626 But there is more than one graph! The one above is concise: it is the
14627 graph of package objects, omitting implicit inputs such as GCC, libc,
14628 grep, etc. It is often useful to have such a concise graph, but
14629 sometimes one may want to see more details. @command{guix graph} supports
14630 several types of graphs, allowing you to choose the level of detail:
14634 This is the default type used in the example above. It shows the DAG of
14635 package objects, excluding implicit dependencies. It is concise, but
14636 filters out many details.
14638 @item reverse-package
14639 This shows the @emph{reverse} DAG of packages. For example:
14642 guix graph --type=reverse-package ocaml
14645 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
14646 you are also interested in cases where OCaml is an implicit dependency, see
14647 @code{reverse-bag} below).
14649 Note that for core packages this can yield huge graphs. If all you want
14650 is to know the number of packages that depend on a given package, use
14651 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
14652 @option{--list-dependent}}).
14655 This is the package DAG, @emph{including} implicit inputs.
14657 For instance, the following command:
14660 guix graph --type=bag-emerged coreutils
14663 ...@: yields this bigger graph:
14665 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
14667 At the bottom of the graph, we see all the implicit inputs of
14668 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
14670 Now, note that the dependencies of these implicit inputs---that is, the
14671 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
14672 here, for conciseness.
14675 Similar to @code{bag-emerged}, but this time including all the bootstrap
14678 @item bag-with-origins
14679 Similar to @code{bag}, but also showing origins and their dependencies.
14682 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
14683 it also takes implicit dependencies into account. For example:
14686 guix graph -t reverse-bag dune
14690 ...@: yields the graph of all packages that depend on Dune, directly or
14691 indirectly. Since Dune is an @emph{implicit} dependency of many packages
14692 @i{via} @code{dune-build-system}, this shows a large number of packages,
14693 whereas @code{reverse-package} would show very few if any.
14696 This is the most detailed representation: It shows the DAG of
14697 derivations (@pxref{Derivations}) and plain store items. Compared to
14698 the above representation, many additional nodes are visible, including
14699 build scripts, patches, Guile modules, etc.
14701 For this type of graph, it is also possible to pass a @file{.drv} file
14702 name instead of a package name, as in:
14705 guix graph -t derivation $(guix system build -d my-config.scm)
14709 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
14710 For example, the following command shows the graph for the package
14711 module that defines the @code{guile} package:
14714 guix graph -t module guile | xdot -
14718 All the types above correspond to @emph{build-time dependencies}. The
14719 following graph type represents the @emph{run-time dependencies}:
14723 This is the graph of @dfn{references} of a package output, as returned
14724 by @command{guix gc --references} (@pxref{Invoking guix gc}).
14726 If the given package output is not available in the store, @command{guix
14727 graph} attempts to obtain dependency information from substitutes.
14729 Here you can also pass a store file name instead of a package name. For
14730 example, the command below produces the reference graph of your profile
14731 (which can be big!):
14734 guix graph -t references $(readlink -f ~/.guix-profile)
14738 This is the graph of the @dfn{referrers} of a store item, as returned by
14739 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
14741 This relies exclusively on local information from your store. For
14742 instance, let us suppose that the current Inkscape is available in 10
14743 profiles on your machine; @command{guix graph -t referrers inkscape}
14744 will show a graph rooted at Inkscape and with those 10 profiles linked
14747 It can help determine what is preventing a store item from being garbage
14752 @cindex shortest path, between packages
14753 Often, the graph of the package you are interested in does not fit on
14754 your screen, and anyway all you want to know is @emph{why} that package
14755 actually depends on some seemingly unrelated package. The
14756 @option{--path} option instructs @command{guix graph} to display the
14757 shortest path between two packages (or derivations, or store items,
14761 $ guix graph --path emacs libunistring
14764 libunistring@@0.9.10
14765 $ guix graph --path -t derivation emacs libunistring
14766 /gnu/store/@dots{}-emacs-26.3.drv
14767 /gnu/store/@dots{}-mailutils-3.9.drv
14768 /gnu/store/@dots{}-libunistring-0.9.10.drv
14769 $ guix graph --path -t references emacs libunistring
14770 /gnu/store/@dots{}-emacs-26.3
14771 /gnu/store/@dots{}-libidn2-2.2.0
14772 /gnu/store/@dots{}-libunistring-0.9.10
14775 Sometimes you still want to visualize the graph but would like to trim
14776 it so it can actually be displayed. One way to do it is via the
14777 @option{--max-depth} (or @option{-M}) option, which lets you specify the
14778 maximum depth of the graph. In the example below, we visualize only
14779 @code{libreoffice} and the nodes whose distance to @code{libreoffice} is
14783 guix graph -M 2 libreoffice | xdot -f fdp -
14786 Mind you, that's still a big ball of spaghetti, but at least
14787 @command{dot} can render it quickly and it can be browsed somewhat.
14789 The available options are the following:
14792 @item --type=@var{type}
14793 @itemx -t @var{type}
14794 Produce a graph output of @var{type}, where @var{type} must be one of
14795 the values listed above.
14798 List the supported graph types.
14800 @item --backend=@var{backend}
14801 @itemx -b @var{backend}
14802 Produce a graph using the selected @var{backend}.
14804 @item --list-backends
14805 List the supported graph backends.
14807 Currently, the available backends are Graphviz and d3.js.
14810 Display the shortest path between two nodes of the type specified by
14811 @option{--type}. The example below shows the shortest path between
14812 @code{libreoffice} and @code{llvm} according to the references of
14813 @code{libreoffice}:
14816 $ guix graph --path -t references libreoffice llvm
14817 /gnu/store/@dots{}-libreoffice-6.4.2.2
14818 /gnu/store/@dots{}-libepoxy-1.5.4
14819 /gnu/store/@dots{}-mesa-19.3.4
14820 /gnu/store/@dots{}-llvm-9.0.1
14823 @item --expression=@var{expr}
14824 @itemx -e @var{expr}
14825 Consider the package @var{expr} evaluates to.
14827 This is useful to precisely refer to a package, as in this example:
14830 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
14833 @item --system=@var{system}
14834 @itemx -s @var{system}
14835 Display the graph for @var{system}---e.g., @code{i686-linux}.
14837 The package dependency graph is largely architecture-independent, but there
14838 are some architecture-dependent bits that this option allows you to visualize.
14840 @item --load-path=@var{directory}
14841 @itemx -L @var{directory}
14842 Add @var{directory} to the front of the package module search path
14843 (@pxref{Package Modules}).
14845 This allows users to define their own packages and make them visible to
14846 the command-line tools.
14849 On top of that, @command{guix graph} supports all the usual package
14850 transformation options (@pxref{Package Transformation Options}). This
14851 makes it easy to view the effect of a graph-rewriting transformation
14852 such as @option{--with-input}. For example, the command below outputs
14853 the graph of @code{git} once @code{openssl} has been replaced by
14854 @code{libressl} everywhere in the graph:
14857 guix graph git --with-input=openssl=libressl
14860 So many possibilities, so much fun!
14862 @node Invoking guix publish
14863 @section Invoking @command{guix publish}
14865 @cindex @command{guix publish}
14866 The purpose of @command{guix publish} is to enable users to easily share
14867 their store with others, who can then use it as a substitute server
14868 (@pxref{Substitutes}).
14870 When @command{guix publish} runs, it spawns an HTTP server which allows
14871 anyone with network access to obtain substitutes from it. This means
14872 that any machine running Guix can also act as if it were a build farm,
14873 since the HTTP interface is compatible with Cuirass, the software behind
14874 the @code{@value{SUBSTITUTE-SERVER-1}} build farm.
14876 For security, each substitute is signed, allowing recipients to check
14877 their authenticity and integrity (@pxref{Substitutes}). Because
14878 @command{guix publish} uses the signing key of the system, which is only
14879 readable by the system administrator, it must be started as root; the
14880 @option{--user} option makes it drop root privileges early on.
14882 The signing key pair must be generated before @command{guix publish} is
14883 launched, using @command{guix archive --generate-key} (@pxref{Invoking
14886 When the @option{--advertise} option is passed, the server advertises
14887 its availability on the local network using multicast DNS (mDNS) and DNS
14888 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
14889 guile-avahi, Using Avahi in Guile Scheme Programs}).
14891 The general syntax is:
14894 guix publish @var{options}@dots{}
14897 Running @command{guix publish} without any additional arguments will
14898 spawn an HTTP server on port 8080:
14904 @cindex socket activation, for @command{guix publish}
14905 @command{guix publish} can also be started following the systemd
14906 ``socket activation'' protocol (@pxref{Service De- and Constructors,
14907 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
14909 Once a publishing server has been authorized, the daemon may download
14910 substitutes from it. @xref{Getting Substitutes from Other Servers}.
14912 By default, @command{guix publish} compresses archives on the fly as it
14913 serves them. This ``on-the-fly'' mode is convenient in that it requires
14914 no setup and is immediately available. However, when serving lots of
14915 clients, we recommend using the @option{--cache} option, which enables
14916 caching of the archives before they are sent to clients---see below for
14917 details. The @command{guix weather} command provides a handy way to
14918 check what a server provides (@pxref{Invoking guix weather}).
14920 As a bonus, @command{guix publish} also serves as a content-addressed
14921 mirror for source files referenced in @code{origin} records
14922 (@pxref{origin Reference}). For instance, assuming @command{guix
14923 publish} is running on @code{example.org}, the following URL returns the
14924 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
14925 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
14928 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
14931 Obviously, these URLs only work for files that are in the store; in
14932 other cases, they return 404 (``Not Found'').
14934 @cindex build logs, publication
14935 Build logs are available from @code{/log} URLs like:
14938 http://example.org/log/gwspk@dots{}-guile-2.2.3
14942 When @command{guix-daemon} is configured to save compressed build logs,
14943 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
14944 URLs return the compressed log as-is, with an appropriate
14945 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
14946 running @command{guix-daemon} with @option{--log-compression=gzip} since
14947 Web browsers can automatically decompress it, which is not the case with
14950 The following options are available:
14953 @item --port=@var{port}
14954 @itemx -p @var{port}
14955 Listen for HTTP requests on @var{port}.
14957 @item --listen=@var{host}
14958 Listen on the network interface for @var{host}. The default is to
14959 accept connections from any interface.
14961 @item --user=@var{user}
14962 @itemx -u @var{user}
14963 Change privileges to @var{user} as soon as possible---i.e., once the
14964 server socket is open and the signing key has been read.
14966 @item --compression[=@var{method}[:@var{level}]]
14967 @itemx -C [@var{method}[:@var{level}]]
14968 Compress data using the given @var{method} and @var{level}. @var{method} is
14969 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
14970 omitted, @code{gzip} is used.
14972 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
14973 to different compression levels: 1 is the fastest, and 9 is the best
14974 (CPU-intensive). The default is 3.
14976 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
14977 small increase in CPU usage; see
14978 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
14979 Web page}. However, @code{lzip} achieves low decompression throughput
14980 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
14981 bottleneck for someone who downloads over a fast network connection.
14983 The compression ratio of @code{zstd} is between that of @code{lzip} and
14984 that of @code{gzip}; its main advantage is a
14985 @uref{https://facebook.github.io/zstd/,high decompression speed}.
14987 Unless @option{--cache} is used, compression occurs on the fly and
14988 the compressed streams are not
14989 cached. Thus, to reduce load on the machine that runs @command{guix
14990 publish}, it may be a good idea to choose a low compression level, to
14991 run @command{guix publish} behind a caching proxy, or to use
14992 @option{--cache}. Using @option{--cache} has the advantage that it
14993 allows @command{guix publish} to add @code{Content-Length} HTTP header
14996 This option can be repeated, in which case every substitute gets compressed
14997 using all the selected methods, and all of them are advertised. This is
14998 useful when users may not support all the compression methods: they can select
14999 the one they support.
15001 @item --cache=@var{directory}
15002 @itemx -c @var{directory}
15003 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
15004 and only serve archives that are in cache.
15006 When this option is omitted, archives and meta-data are created
15007 on-the-fly. This can reduce the available bandwidth, especially when
15008 compression is enabled, since this may become CPU-bound. Another
15009 drawback of the default mode is that the length of archives is not known
15010 in advance, so @command{guix publish} does not add a
15011 @code{Content-Length} HTTP header to its responses, which in turn
15012 prevents clients from knowing the amount of data being downloaded.
15014 Conversely, when @option{--cache} is used, the first request for a store
15015 item (@i{via} a @code{.narinfo} URL) triggers a
15016 background process to @dfn{bake} the archive---computing its
15017 @code{.narinfo} and compressing the archive, if needed. Once the
15018 archive is cached in @var{directory}, subsequent requests succeed and
15019 are served directly from the cache, which guarantees that clients get
15020 the best possible bandwidth.
15022 That first @code{.narinfo} request nonetheless returns 200, provided the
15023 requested store item is ``small enough'', below the cache bypass
15024 threshold---see @option{--cache-bypass-threshold} below. That way,
15025 clients do not have to wait until the archive is baked. For larger
15026 store items, the first @code{.narinfo} request returns 404, meaning that
15027 clients have to wait until the archive is baked.
15029 The ``baking'' process is performed by worker threads. By default, one
15030 thread per CPU core is created, but this can be customized. See
15031 @option{--workers} below.
15033 When @option{--ttl} is used, cached entries are automatically deleted
15034 when they have expired.
15036 @item --workers=@var{N}
15037 When @option{--cache} is used, request the allocation of @var{N} worker
15038 threads to ``bake'' archives.
15040 @item --ttl=@var{ttl}
15041 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
15042 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
15043 days, @code{1m} means 1 month, and so on.
15045 This allows the user's Guix to keep substitute information in cache for
15046 @var{ttl}. However, note that @code{guix publish} does not itself
15047 guarantee that the store items it provides will indeed remain available
15048 for as long as @var{ttl}.
15050 Additionally, when @option{--cache} is used, cached entries that have
15051 not been accessed for @var{ttl} and that no longer have a corresponding
15052 item in the store, may be deleted.
15054 @item --negative-ttl=@var{ttl}
15055 Similarly produce @code{Cache-Control} HTTP headers to advertise the
15056 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
15057 which the HTTP 404 code is returned. By default, no negative TTL is
15060 This parameter can help adjust server load and substitute latency by
15061 instructing cooperating clients to be more or less patient when a store
15064 @item --cache-bypass-threshold=@var{size}
15065 When used in conjunction with @option{--cache}, store items smaller than
15066 @var{size} are immediately available, even when they are not yet in
15067 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
15068 for megabytes and so on. The default is @code{10M}.
15070 ``Cache bypass'' allows you to reduce the publication delay for clients
15071 at the expense of possibly additional I/O and CPU use on the server
15072 side: depending on the client access patterns, those store items can end
15073 up being baked several times until a copy is available in cache.
15075 Increasing the threshold may be useful for sites that have few users, or
15076 to guarantee that users get substitutes even for store items that are
15079 @item --nar-path=@var{path}
15080 Use @var{path} as the prefix for the URLs of ``nar'' files
15081 (@pxref{Invoking guix archive, normalized archives}).
15083 By default, nars are served at a URL such as
15084 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
15085 change the @code{/nar} part to @var{path}.
15087 @item --public-key=@var{file}
15088 @itemx --private-key=@var{file}
15089 Use the specific @var{file}s as the public/private key pair used to sign
15090 the store items being published.
15092 The files must correspond to the same key pair (the private key is used
15093 for signing and the public key is merely advertised in the signature
15094 metadata). They must contain keys in the canonical s-expression format
15095 as produced by @command{guix archive --generate-key} (@pxref{Invoking
15096 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
15097 @file{/etc/guix/signing-key.sec} are used.
15099 @item --repl[=@var{port}]
15100 @itemx -r [@var{port}]
15101 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
15102 Reference Manual}) on @var{port} (37146 by default). This is used
15103 primarily for debugging a running @command{guix publish} server.
15106 Enabling @command{guix publish} on Guix System is a one-liner: just
15107 instantiate a @code{guix-publish-service-type} service in the @code{services} field
15108 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
15109 @code{guix-publish-service-type}}).
15111 If you are instead running Guix on a ``foreign distro'', follow these
15116 If your host distro uses the systemd init system:
15119 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
15120 /etc/systemd/system/
15121 # systemctl start guix-publish && systemctl enable guix-publish
15125 If your host distro uses the Upstart init system:
15128 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
15129 # start guix-publish
15133 Otherwise, proceed similarly with your distro's init system.
15136 @node Invoking guix challenge
15137 @section Invoking @command{guix challenge}
15139 @cindex reproducible builds
15140 @cindex verifiable builds
15141 @cindex @command{guix challenge}
15143 Do the binaries provided by this server really correspond to the source
15144 code it claims to build? Is a package build process deterministic?
15145 These are the questions the @command{guix challenge} command attempts to
15148 The former is obviously an important question: Before using a substitute
15149 server (@pxref{Substitutes}), one had better @emph{verify} that it
15150 provides the right binaries, and thus @emph{challenge} it. The latter
15151 is what enables the former: If package builds are deterministic, then
15152 independent builds of the package should yield the exact same result,
15153 bit for bit; if a server provides a binary different from the one
15154 obtained locally, it may be either corrupt or malicious.
15156 We know that the hash that shows up in @file{/gnu/store} file names is
15157 the hash of all the inputs of the process that built the file or
15158 directory---compilers, libraries, build scripts,
15159 etc. (@pxref{Introduction}). Assuming deterministic build processes,
15160 one store file name should map to exactly one build output.
15161 @command{guix challenge} checks whether there is, indeed, a single
15162 mapping by comparing the build outputs of several independent builds of
15163 any given store item.
15165 The command output looks like this:
15169 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org" \
15170 openssl git pius coreutils grep
15171 updating substitutes from 'https://@value{SUBSTITUTE-SERVER-1}'... 100.0%
15172 updating substitutes from 'https://guix.example.org'... 100.0%
15173 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
15174 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15175 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15176 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
15178 /lib/libcrypto.so.1.1
15181 /gnu/store/@dots{}-git-2.5.0 contents differ:
15182 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
15183 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
15184 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
15186 /libexec/git-core/git-fsck
15188 /gnu/store/@dots{}-pius-2.1.1 contents differ:
15189 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15190 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15191 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
15193 /share/man/man1/pius.1.gz
15197 5 store items were analyzed:
15198 - 2 (40.0%) were identical
15199 - 3 (60.0%) differed
15200 - 0 (0.0%) were inconclusive
15204 In this example, @command{guix challenge} queries all the substitute
15205 servers for each of the fives packages specified on the command line.
15206 It then reports those store items for which the servers obtained a
15207 result different from the local build (if it exists) and/or different
15208 from one another; here, the @samp{local hash} lines indicate that a
15209 local build result was available for each of these packages and shows
15212 @cindex non-determinism, in package builds
15213 As an example, @code{guix.example.org} always gets a different answer.
15214 Conversely, @code{@value{SUBSTITUTE-SERVER-1}} agrees with local builds, except in the
15215 case of Git. This might indicate that the build process of Git is
15216 non-deterministic, meaning that its output varies as a function of
15217 various things that Guix does not fully control, in spite of building
15218 packages in isolated environments (@pxref{Features}). Most common
15219 sources of non-determinism include the addition of timestamps in build
15220 results, the inclusion of random numbers, and directory listings sorted
15221 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
15224 To find out what is wrong with this Git binary, the easiest approach is
15228 guix challenge git \
15229 --diff=diffoscope \
15230 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
15233 This automatically invokes @command{diffoscope}, which displays detailed
15234 information about files that differ.
15236 Alternatively, we can do something along these lines (@pxref{Invoking guix
15240 $ wget -q -O - https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-git-2.5.0 \
15241 | lzip -d | guix archive -x /tmp/git
15242 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
15245 This command shows the difference between the files resulting from the
15246 local build, and the files resulting from the build on
15247 @code{@value{SUBSTITUTE-SERVER-1}} (@pxref{Overview, Comparing and Merging Files,,
15248 diffutils, Comparing and Merging Files}). The @command{diff} command
15249 works great for text files. When binary files differ, a better option
15250 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
15251 visualize differences for all kinds of files.
15253 Once you have done that work, you can tell whether the differences are due
15254 to a non-deterministic build process or to a malicious server. We try
15255 hard to remove sources of non-determinism in packages to make it easier
15256 to verify substitutes, but of course, this is a process that
15257 involves not just Guix, but a large part of the free software community.
15258 In the meantime, @command{guix challenge} is one tool to help address
15261 If you are writing packages for Guix, you are encouraged to check
15262 whether @code{@value{SUBSTITUTE-SERVER-1}} and other substitute servers obtain the
15263 same build result as you did with:
15266 guix challenge @var{package}
15269 The general syntax is:
15272 guix challenge @var{options} @var{argument}@dots{}
15276 where @var{argument} is a package specification such as
15277 @code{guile@@2.0} or @code{glibc:debug} or, alternatively, a store file
15278 name as returned, for example, by @command{guix build} or @command{guix
15281 When a difference is found between the hash of a locally-built item and
15282 that of a server-provided substitute, or among substitutes provided by
15283 different servers, the command displays it as in the example above and
15284 its exit code is 2 (other non-zero exit codes denote other kinds of
15287 The one option that matters is:
15291 @item --substitute-urls=@var{urls}
15292 Consider @var{urls} the whitespace-separated list of substitute source
15293 URLs to compare to.
15295 @item --diff=@var{mode}
15296 Upon mismatches, show differences according to @var{mode}, one of:
15299 @item @code{simple} (the default)
15300 Show the list of files that differ.
15302 @item @code{diffoscope}
15303 @itemx @var{command}
15304 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
15305 two directories whose contents do not match.
15307 When @var{command} is an absolute file name, run @var{command} instead
15311 Do not show further details about the differences.
15314 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
15315 downloads the store items from the given substitute servers so that it
15320 Show details about matches (identical contents) in addition to
15321 information about mismatches.
15325 @node Invoking guix copy
15326 @section Invoking @command{guix copy}
15328 @cindex copy, of store items, over SSH
15329 @cindex SSH, copy of store items
15330 @cindex sharing store items across machines
15331 @cindex transferring store items across machines
15332 The @command{guix copy} command copies items from the store of one
15333 machine to that of another machine over a secure shell (SSH)
15334 connection@footnote{This command is available only when Guile-SSH was
15335 found. @xref{Requirements}, for details.}. For example, the following
15336 command copies the @code{coreutils} package, the user's profile, and all
15337 their dependencies over to @var{host}, logged in as @var{user}:
15340 guix copy --to=@var{user}@@@var{host} \
15341 coreutils $(readlink -f ~/.guix-profile)
15344 If some of the items to be copied are already present on @var{host},
15345 they are not actually sent.
15347 The command below retrieves @code{libreoffice} and @code{gimp} from
15348 @var{host}, assuming they are available there:
15351 guix copy --from=@var{host} libreoffice gimp
15354 The SSH connection is established using the Guile-SSH client, which is
15355 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
15356 @file{~/.ssh/config}, and uses the SSH agent for authentication.
15358 The key used to sign items that are sent must be accepted by the remote
15359 machine. Likewise, the key used by the remote machine to sign items you
15360 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
15361 own daemon. @xref{Invoking guix archive}, for more information about
15362 store item authentication.
15364 The general syntax is:
15367 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
15370 You must always specify one of the following options:
15373 @item --to=@var{spec}
15374 @itemx --from=@var{spec}
15375 Specify the host to send to or receive from. @var{spec} must be an SSH
15376 spec such as @code{example.org}, @code{charlie@@example.org}, or
15377 @code{charlie@@example.org:2222}.
15380 The @var{items} can be either package names, such as @code{gimp}, or
15381 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
15383 When specifying the name of a package to send, it is first built if
15384 needed, unless @option{--dry-run} was specified. Common build options
15385 are supported (@pxref{Common Build Options}).
15388 @node Invoking guix container
15389 @section Invoking @command{guix container}
15391 @cindex @command{guix container}
15393 As of version @value{VERSION}, this tool is experimental. The interface
15394 is subject to radical change in the future.
15397 The purpose of @command{guix container} is to manipulate processes
15398 running within an isolated environment, commonly known as a
15399 ``container'', typically created by the @command{guix shell}
15400 (@pxref{Invoking guix shell}) and @command{guix system container}
15401 (@pxref{Invoking guix system}) commands.
15403 The general syntax is:
15406 guix container @var{action} @var{options}@dots{}
15409 @var{action} specifies the operation to perform with a container, and
15410 @var{options} specifies the context-specific arguments for the action.
15412 The following actions are available:
15416 Execute a command within the context of a running container.
15421 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
15424 @var{pid} specifies the process ID of the running container.
15425 @var{program} specifies an executable file name within the root file
15426 system of the container. @var{arguments} are the additional options that
15427 will be passed to @var{program}.
15429 The following command launches an interactive login shell inside a
15430 Guix system container, started by @command{guix system container}, and whose
15431 process ID is 9001:
15434 guix container exec 9001 /run/current-system/profile/bin/bash --login
15437 Note that the @var{pid} cannot be the parent process of a container. It
15438 must be PID 1 of the container or one of its child processes.
15442 @node Invoking guix weather
15443 @section Invoking @command{guix weather}
15445 Occasionally you're grumpy because substitutes are lacking and you end
15446 up building packages by yourself (@pxref{Substitutes}). The
15447 @command{guix weather} command reports on substitute availability on the
15448 specified servers so you can have an idea of whether you'll be grumpy
15449 today. It can sometimes be useful info as a user, but it is primarily
15450 useful to people running @command{guix publish} (@pxref{Invoking guix
15453 @cindex statistics, for substitutes
15454 @cindex availability of substitutes
15455 @cindex substitute availability
15456 @cindex weather, substitute availability
15457 Here's a sample run:
15460 $ guix weather --substitute-urls=https://guix.example.org
15461 computing 5,872 package derivations for x86_64-linux...
15462 looking for 6,128 store items on https://guix.example.org..
15463 updating substitutes from 'https://guix.example.org'... 100.0%
15464 https://guix.example.org
15465 43.4% substitutes available (2,658 out of 6,128)
15466 7,032.5 MiB of nars (compressed)
15467 19,824.2 MiB on disk (uncompressed)
15468 0.030 seconds per request (182.9 seconds in total)
15469 33.5 requests per second
15471 9.8% (342 out of 3,470) of the missing items are queued
15473 x86_64-linux: 518 (59.7%)
15474 i686-linux: 221 (25.5%)
15475 aarch64-linux: 128 (14.8%)
15476 build rate: 23.41 builds per hour
15477 x86_64-linux: 11.16 builds per hour
15478 i686-linux: 6.03 builds per hour
15479 aarch64-linux: 6.41 builds per hour
15482 @cindex continuous integration, statistics
15483 As you can see, it reports the fraction of all the packages for which
15484 substitutes are available on the server---regardless of whether
15485 substitutes are enabled, and regardless of whether this server's signing
15486 key is authorized. It also reports the size of the compressed archives
15487 (``nars'') provided by the server, the size the corresponding store
15488 items occupy in the store (assuming deduplication is turned off), and
15489 the server's throughput. The second part gives continuous integration
15490 (CI) statistics, if the server supports it. In addition, using the
15491 @option{--coverage} option, @command{guix weather} can list ``important''
15492 package substitutes missing on the server (see below).
15494 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
15495 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
15496 challenge}, it ignores signatures on those substitutes, which is
15497 innocuous since the command only gathers statistics and cannot install
15500 The general syntax is:
15503 guix weather @var{options}@dots{} [@var{packages}@dots{}]
15506 When @var{packages} is omitted, @command{guix weather} checks the availability
15507 of substitutes for @emph{all} the packages, or for those specified with
15508 @option{--manifest}; otherwise it only considers the specified packages. It
15509 is also possible to query specific system types with @option{--system}.
15510 @command{guix weather} exits with a non-zero code when the fraction of
15511 available substitutes is below 100%.
15513 The available options are listed below.
15516 @item --substitute-urls=@var{urls}
15517 @var{urls} is the space-separated list of substitute server URLs to
15518 query. When this option is omitted, the default set of substitute
15519 servers is queried.
15521 @item --system=@var{system}
15522 @itemx -s @var{system}
15523 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
15524 option can be repeated, in which case @command{guix weather} will query
15525 substitutes for several system types.
15527 @item --manifest=@var{file}
15528 Instead of querying substitutes for all the packages, only ask for those
15529 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
15530 with the @code{-m} option of @command{guix package} (@pxref{Invoking
15533 This option can be repeated several times, in which case the manifests
15536 @item --coverage[=@var{count}]
15537 @itemx -c [@var{count}]
15538 Report on substitute coverage for packages: list packages with at least
15539 @var{count} dependents (zero by default) for which substitutes are
15540 unavailable. Dependent packages themselves are not listed: if @var{b} depends
15541 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
15542 @var{b} usually lacks substitutes as well. The result looks like this:
15545 $ guix weather --substitute-urls=@value{SUBSTITUTE-URLS} -c 10
15546 computing 8,983 package derivations for x86_64-linux...
15547 looking for 9,343 store items on @value{SUBSTITUTE-URLS}...
15548 updating substitutes from '@value{SUBSTITUTE-URLS}'... 100.0%
15549 @value{SUBSTITUTE-URLS}
15550 64.7% substitutes available (6,047 out of 9,343)
15552 2502 packages are missing from '@value{SUBSTITUTE-URLS}' for 'x86_64-linux', among which:
15553 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
15554 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
15555 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
15559 What this example shows is that @code{kcoreaddons} and presumably the 58
15560 packages that depend on it have no substitutes at
15561 @code{@value{SUBSTITUTE-SERVER-1}}; likewise for @code{qgpgme} and the 46
15562 packages that depend on it.
15564 If you are a Guix developer, or if you are taking care of this build farm,
15565 you'll probably want to have a closer look at these packages: they may simply
15568 @item --display-missing
15569 Display the list of store items for which substitutes are missing.
15572 @node Invoking guix processes
15573 @section Invoking @command{guix processes}
15575 The @command{guix processes} command can be useful to developers and system
15576 administrators, especially on multi-user machines and on build farms: it lists
15577 the current sessions (connections to the daemon), as well as information about
15578 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
15579 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
15580 listed.}. Here's an example of the information it returns:
15583 $ sudo guix processes
15586 ClientCommand: guix shell python
15590 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
15594 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15595 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
15596 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
15597 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
15599 ChildCommand: guix offload x86_64-linux 7200 1 28800
15601 ChildCommand: guix offload x86_64-linux 7200 1 28800
15603 ChildCommand: guix offload x86_64-linux 7200 1 28800
15606 In this example we see that @command{guix-daemon} has three clients:
15607 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
15608 integration tool; their process identifier (PID) is given by the
15609 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
15610 @command{guix-daemon} sub-process of this particular session.
15612 The @code{LockHeld} fields show which store items are currently locked
15613 by this session, which corresponds to store items being built or
15614 substituted (the @code{LockHeld} field is not displayed when
15615 @command{guix processes} is not running as root). Last, by looking at
15616 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
15617 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
15619 The output is in Recutils format so we can use the handy @command{recsel}
15620 command to select sessions of interest (@pxref{Selection Expressions,,,
15621 recutils, GNU recutils manual}). As an example, the command shows the command
15622 line and PID of the client that triggered the build of a Perl package:
15625 $ sudo guix processes | \
15626 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
15628 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15631 Additional options are listed below.
15634 @item --format=@var{format}
15635 @itemx -f @var{format}
15636 Produce output in the specified @var{format}, one of:
15640 The default option. It outputs a set of Session recutils records
15641 that include each @code{ChildProcess} as a field.
15644 Normalize the output records into record sets (@pxref{Record Sets,,,
15645 recutils, GNU recutils manual}). Normalizing into record sets allows
15646 joins across record types. The example below lists the PID of each
15647 @code{ChildProcess} and the associated PID for @code{Session} that
15648 spawned the @code{ChildProcess} where the @code{Session} was started
15649 using @command{guix build}.
15652 $ guix processes --format=normalized | \
15656 -p Session.PID,PID \
15657 -e 'Session.ClientCommand ~ "guix build"'
15670 @node Foreign Architectures
15671 @chapter Foreign Architectures
15673 You can target computers of different CPU architectures when producing
15674 packages (@pxref{Invoking guix package}), packs (@pxref{Invoking guix
15675 pack}) or full systems (@pxref{Invoking guix system}).
15677 GNU Guix supports two distinct mechanisms to target foreign
15683 @uref{https://en.wikipedia.org/wiki/Cross_compiler,cross-compilation}
15686 The native building mechanism which consists in building using the CPU
15687 instruction set of the foreign system you are targeting. It often
15688 requires emulation, using the QEMU program for instance.
15692 * Cross-Compilation:: Cross-compiling for another architecture.
15693 * Native Builds:: Targeting another architecture through native builds.
15696 @node Cross-Compilation
15697 @section Cross-Compilation
15699 @cindex foreign architectures
15700 The commands supporting cross-compilation are proposing the
15701 @option{--list-targets} and @option{--target} options.
15703 The @option{--list-targets} option lists all the supported targets that
15704 can be passed as an argument to @option{--target}.
15707 $ guix build --list-targets
15708 The available targets are:
15710 - aarch64-linux-gnu
15711 - arm-linux-gnueabihf
15715 - mips64el-linux-gnu
15716 - powerpc-linux-gnu
15717 - powerpc64le-linux-gnu
15718 - riscv64-linux-gnu
15720 - x86_64-w64-mingw32
15723 Targets are specified as GNU triplets (@pxref{Specifying Target
15724 Triplets, GNU configuration triplets,, autoconf, Autoconf}).
15726 Those triplets are passed to GCC and the other underlying compilers
15727 possibly involved when building a package, a system image or any other
15731 $ guix build --target=aarch64-linux-gnu hello
15732 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12
15734 $ file /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello
15735 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello: ELF
15736 64-bit LSB executable, ARM aarch64 @dots{}
15739 The major benefit of cross-compilation is that there are no performance
15740 penaly compared to emulation using QEMU. There are however higher risks
15741 that some packages fail to cross-compile because few users are using
15742 this mechanism extensively.
15744 @node Native Builds
15745 @section Native Builds
15747 The commands that support impersonating a specific system have the
15748 @option{--list-systems} and @option{--system} options.
15750 The @option{--list-systems} option lists all the supported systems that
15751 can be passed as an argument to @option{--system}.
15754 $ guix build --list-systems
15755 The available systems are:
15757 - x86_64-linux [current]
15764 - powerpc64le-linux
15767 $ guix build --system=i686-linux hello
15768 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12
15770 $ file /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello
15771 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello: ELF
15772 32-bit LSB executable, Intel 80386 @dots{}
15775 In the above example, the current system is @var{x86_64-linux}. The
15776 @var{hello} package is however built for the @var{i686-linux} system.
15778 This is possible because the @var{i686} CPU instruction set is a subset
15779 of the @var{x86_64}, hence @var{i686} targeting binaries can be run on
15782 Still in the context of the previous example, if picking the
15783 @var{aarch64-linux} system and the @command{guix build
15784 --system=aarch64-linux hello} has to build some derivations, an extra
15785 step might be needed.
15787 The @var{aarch64-linux} targeting binaries cannot directly be run on a
15788 @var{x86_64-linux} system. An emulation layer is requested. The GNU
15789 Guix daemon can take advantage of the Linux kernel
15790 @uref{https://en.wikipedia.org/wiki/Binfmt_misc,binfmt_misc} mechanism
15791 for that. In short, the Linux kernel can defer the execution of a
15792 binary targeting a foreign platform, here @var{aarch64-linux}, to a
15793 userspace program, usually an emulator.
15795 There is a service that registers QEMU as a backend for the
15796 @code{binfmt_misc} mechanism (@pxref{Virtualization Services,
15797 @code{qemu-binfmt-service-type}}). On Debian based foreign
15798 distributions, the alternative would be the @code{qemu-user-static}
15801 If the @code{binfmt_misc} mechanism is not setup correctly, the building
15802 will fail this way:
15805 $ guix build --system=armhf-linux hello --check
15807 @ unsupported-platform /gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv aarch64-linux
15808 while setting up the build environment: a `aarch64-linux' is required to
15809 build `/gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv', but
15810 I am a `x86_64-linux'@dots{}
15813 whereas, with the @code{binfmt_misc} mechanism correctly linked with
15814 QEMU, one can expect to see:
15817 $ guix build --system=armhf-linux hello --check
15818 /gnu/store/13xz4nghg39wpymivlwghy08yzj97hlj-hello-2.12
15821 The main advantage of native building compared to cross-compiling, is
15822 that more packages are likely to build correctly. However it comes at a
15823 price: compilation backed by QEMU is @emph{way slower} than
15824 cross-compilation, because every instruction needs to be emulated.
15826 The availability of substitutes for the architecture targeted by the
15827 @code{--system} option can mitigate this problem. An other way to work
15828 around it is to install GNU Guix on a machine whose CPU supports
15829 the targeted instruction set, and set it up as an offload machine
15830 (@pxref{Daemon Offload Setup}).
15832 @node System Configuration
15833 @chapter System Configuration
15835 @cindex system configuration
15836 Guix System supports a consistent whole-system configuration
15837 mechanism. By that we mean that all aspects of the global system
15838 configuration---such as the available system services, timezone and
15839 locale settings, user accounts---are declared in a single place. Such
15840 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
15842 One of the advantages of putting all the system configuration under the
15843 control of Guix is that it supports transactional system upgrades, and
15844 makes it possible to roll back to a previous system instantiation,
15845 should something go wrong with the new one (@pxref{Features}). Another
15846 advantage is that it makes it easy to replicate the exact same configuration
15847 across different machines, or at different points in time, without
15848 having to resort to additional administration tools layered on top of
15849 the own tools of the system.
15850 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
15852 This section describes this mechanism. First we focus on the system
15853 administrator's viewpoint---explaining how the system is configured and
15854 instantiated. Then we show how this mechanism can be extended, for
15855 instance to support new system services.
15858 * Using the Configuration System:: Customizing your GNU system.
15859 * operating-system Reference:: Detail of operating-system declarations.
15860 * File Systems:: Configuring file system mounts.
15861 * Mapped Devices:: Block device extra processing.
15862 * Swap Space:: Backing RAM with disk space.
15863 * User Accounts:: Specifying user accounts.
15864 * Keyboard Layout:: How the system interprets key strokes.
15865 * Locales:: Language and cultural convention settings.
15866 * Services:: Specifying system services.
15867 * Setuid Programs:: Programs running with elevated privileges.
15868 * X.509 Certificates:: Authenticating HTTPS servers.
15869 * Name Service Switch:: Configuring libc's name service switch.
15870 * Initial RAM Disk:: Linux-Libre bootstrapping.
15871 * Bootloader Configuration:: Configuring the boot loader.
15872 * Invoking guix system:: Instantiating a system configuration.
15873 * Invoking guix deploy:: Deploying a system configuration to a remote host.
15874 * Running Guix in a VM:: How to run Guix System in a virtual machine.
15875 * Defining Services:: Adding new service definitions.
15878 @node Using the Configuration System
15879 @section Using the Configuration System
15881 The operating system is configured by providing an
15882 @code{operating-system} declaration in a file that can then be passed to
15883 the @command{guix system} command (@pxref{Invoking guix system}). A
15884 simple setup, with the default system services, the default Linux-Libre
15885 kernel, initial RAM disk, and boot loader looks like this:
15887 @findex operating-system
15889 @include os-config-bare-bones.texi
15892 This example should be self-describing. Some of the fields defined
15893 above, such as @code{host-name} and @code{bootloader}, are mandatory.
15894 Others, such as @code{packages} and @code{services}, can be omitted, in
15895 which case they get a default value.
15897 Below we discuss the effect of some of the most important fields
15898 (@pxref{operating-system Reference}, for details about all the available
15899 fields), and how to @dfn{instantiate} the operating system using
15900 @command{guix system}.
15902 @unnumberedsubsec Bootloader
15904 @cindex legacy boot, on Intel machines
15905 @cindex BIOS boot, on Intel machines
15908 The @code{bootloader} field describes the method that will be used to boot
15909 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
15910 mode, as in the example above. However, more recent machines rely instead on
15911 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
15912 the @code{bootloader} field should contain something along these lines:
15915 (bootloader-configuration
15916 (bootloader grub-efi-bootloader)
15917 (targets '("/boot/efi")))
15920 @xref{Bootloader Configuration}, for more information on the available
15921 configuration options.
15923 @unnumberedsubsec Globally-Visible Packages
15925 @vindex %base-packages
15926 The @code{packages} field lists packages that will be globally visible
15927 on the system, for all user accounts---i.e., in every user's @env{PATH}
15928 environment variable---in addition to the per-user profiles
15929 (@pxref{Invoking guix package}). The @code{%base-packages} variable
15930 provides all the tools one would expect for basic user and administrator
15931 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
15932 the @command{mg} lightweight text editor, @command{find}, @command{grep},
15933 etc. The example above adds GNU@tie{}Screen to those,
15934 taken from the @code{(gnu packages screen)}
15935 module (@pxref{Package Modules}). The
15936 @code{(list package output)} syntax can be used to add a specific output
15940 (use-modules (gnu packages))
15941 (use-modules (gnu packages dns))
15945 (packages (cons (list isc-bind "utils")
15949 @findex specification->package
15950 Referring to packages by variable name, like @code{isc-bind} above, has
15951 the advantage of being unambiguous; it also allows typos and such to be
15952 diagnosed right away as ``unbound variables''. The downside is that one
15953 needs to know which module defines which package, and to augment the
15954 @code{use-package-modules} line accordingly. To avoid that, one can use
15955 the @code{specification->package} procedure of the @code{(gnu packages)}
15956 module, which returns the best package for a given name or name and
15960 (use-modules (gnu packages))
15964 (packages (append (map specification->package
15965 '("tcpdump" "htop" "gnupg@@2.0"))
15969 @unnumberedsubsec System Services
15972 @vindex %base-services
15973 The @code{services} field lists @dfn{system services} to be made
15974 available when the system starts (@pxref{Services}).
15975 The @code{operating-system} declaration above specifies that, in
15976 addition to the basic services, we want the OpenSSH secure shell
15977 daemon listening on port 2222 (@pxref{Networking Services,
15978 @code{openssh-service-type}}). Under the hood,
15979 @code{openssh-service-type} arranges so that @command{sshd} is started with the
15980 right command-line options, possibly with supporting configuration files
15981 generated as needed (@pxref{Defining Services}).
15983 @cindex customization, of services
15984 @findex modify-services
15985 Occasionally, instead of using the base services as is, you will want to
15986 customize them. To do this, use @code{modify-services} (@pxref{Service
15987 Reference, @code{modify-services}}) to modify the list.
15989 @anchor{auto-login to TTY} For example, suppose you want to modify
15990 @code{guix-daemon} and Mingetty (the console log-in) in the
15991 @code{%base-services} list (@pxref{Base Services,
15992 @code{%base-services}}). To do that, you can write the following in
15993 your operating system declaration:
15996 (define %my-services
15997 ;; My very own list of services.
15998 (modify-services %base-services
15999 (guix-service-type config =>
16000 (guix-configuration
16002 ;; Fetch substitutes from example.org.
16004 (list "https://example.org/guix"
16005 "https://ci.guix.gnu.org"))))
16006 (mingetty-service-type config =>
16007 (mingetty-configuration
16009 ;; Automatically log in as "guest".
16010 (auto-login "guest")))))
16014 (services %my-services))
16017 This changes the configuration---i.e., the service parameters---of the
16018 @code{guix-service-type} instance, and that of all the
16019 @code{mingetty-service-type} instances in the @code{%base-services} list
16020 (@pxref{Auto-Login to a Specific TTY, see the cookbook for how to
16021 auto-login one user to a specific TTY,, guix-cookbook, GNU Guix Cookbook})).
16022 Observe how this is accomplished: first, we arrange for the original
16023 configuration to be bound to the identifier @code{config} in the
16024 @var{body}, and then we write the @var{body} so that it evaluates to the
16025 desired configuration. In particular, notice how we use @code{inherit}
16026 to create a new configuration which has the same values as the old
16027 configuration, but with a few modifications.
16029 @cindex encrypted disk
16030 The configuration for a typical ``desktop'' usage, with an encrypted
16031 root partition, a swap file on the root partition, the X11 display
16032 server, GNOME and Xfce (users can choose which of these desktop
16033 environments to use at the log-in screen by pressing @kbd{F1}), network
16034 management, power management, and more, would look like this:
16037 @include os-config-desktop.texi
16040 A graphical system with a choice of lightweight window managers
16041 instead of full-blown desktop environments would look like this:
16044 @include os-config-lightweight-desktop.texi
16047 This example refers to the @file{/boot/efi} file system by its UUID,
16048 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
16049 as returned by the @command{blkid} command.
16051 @xref{Desktop Services}, for the exact list of services provided by
16052 @code{%desktop-services}. @xref{X.509 Certificates}, for background
16053 information about the @code{nss-certs} package that is used here.
16055 Again, @code{%desktop-services} is just a list of service objects. If
16056 you want to remove services from there, you can do so using the
16057 procedures for list filtering (@pxref{SRFI-1 Filtering and
16058 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
16059 following expression returns a list that contains all the services in
16060 @code{%desktop-services} minus the Avahi service:
16063 (remove (lambda (service)
16064 (eq? (service-kind service) avahi-service-type))
16068 Alternatively, the @code{modify-services} macro can be used:
16071 (modify-services %desktop-services
16072 (delete avahi-service-type))
16076 @unnumberedsubsec Instantiating the System
16078 Assuming the @code{operating-system} declaration
16079 is stored in the @file{my-system-config.scm}
16080 file, the @command{guix system reconfigure my-system-config.scm} command
16081 instantiates that configuration, and makes it the default GRUB boot
16082 entry (@pxref{Invoking guix system}).
16085 We recommend that you keep this @file{my-system-config.scm} file safe
16086 and under version control to easily track changes to your configuration.
16089 The normal way to change the system configuration is by updating this
16090 file and re-running @command{guix system reconfigure}. One should never
16091 have to touch files in @file{/etc} or to run commands that modify the
16092 system state such as @command{useradd} or @command{grub-install}. In
16093 fact, you must avoid that since that would not only void your warranty
16094 but also prevent you from rolling back to previous versions of your
16095 system, should you ever need to.
16097 @cindex roll-back, of the operating system
16098 Speaking of roll-back, each time you run @command{guix system
16099 reconfigure}, a new @dfn{generation} of the system is created---without
16100 modifying or deleting previous generations. Old system generations get
16101 an entry in the bootloader boot menu, allowing you to boot them in case
16102 something went wrong with the latest generation. Reassuring, no? The
16103 @command{guix system list-generations} command lists the system
16104 generations available on disk. It is also possible to roll back the
16105 system via the commands @command{guix system roll-back} and
16106 @command{guix system switch-generation}.
16108 Although the @command{guix system reconfigure} command will not modify
16109 previous generations, you must take care when the current generation is not
16110 the latest (e.g., after invoking @command{guix system roll-back}), since
16111 the operation might overwrite a later generation (@pxref{Invoking guix
16114 @unnumberedsubsec The Programming Interface
16116 At the Scheme level, the bulk of an @code{operating-system} declaration
16117 is instantiated with the following monadic procedure (@pxref{The Store
16120 @deffn {Monadic Procedure} operating-system-derivation os
16121 Return a derivation that builds @var{os}, an @code{operating-system}
16122 object (@pxref{Derivations}).
16124 The output of the derivation is a single directory that refers to all
16125 the packages, configuration files, and other supporting files needed to
16126 instantiate @var{os}.
16129 This procedure is provided by the @code{(gnu system)} module. Along
16130 with @code{(gnu services)} (@pxref{Services}), this module contains the
16131 guts of Guix System. Make sure to visit it!
16134 @node operating-system Reference
16135 @section @code{operating-system} Reference
16137 This section summarizes all the options available in
16138 @code{operating-system} declarations (@pxref{Using the Configuration
16141 @deftp {Data Type} operating-system
16142 This is the data type representing an operating system configuration.
16143 By that, we mean all the global system configuration, not per-user
16144 configuration (@pxref{Using the Configuration System}).
16147 @item @code{kernel} (default: @code{linux-libre})
16148 The package object of the operating system kernel to
16149 use@footnote{Currently only the Linux-libre kernel is fully supported.
16150 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
16151 available when building a virtual machine disk image.}.
16154 @item @code{hurd} (default: @code{#f})
16155 The package object of the Hurd to be started by the kernel. When this
16156 field is set, produce a GNU/Hurd operating system. In that case,
16157 @code{kernel} must also be set to the @code{gnumach} package---the
16158 microkernel the Hurd runs on.
16161 This feature is experimental and only supported for disk images.
16164 @item @code{kernel-loadable-modules} (default: '())
16165 A list of objects (usually packages) to collect loadable kernel modules
16166 from--e.g. @code{(list ddcci-driver-linux)}.
16168 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
16169 List of strings or gexps representing additional arguments to pass on
16170 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
16172 @item @code{bootloader}
16173 The system bootloader configuration object. @xref{Bootloader Configuration}.
16176 This is the label (a string) as it appears in the bootloader's menu entry.
16177 The default label includes the kernel name and version.
16179 @item @code{keyboard-layout} (default: @code{#f})
16180 This field specifies the keyboard layout to use in the console. It can be
16181 either @code{#f}, in which case the default keyboard layout is used (usually
16182 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
16183 for more information.
16185 This keyboard layout is in effect as soon as the kernel has booted. For
16186 instance, it is the keyboard layout in effect when you type a passphrase if
16187 your root file system is on a @code{luks-device-mapping} mapped device
16188 (@pxref{Mapped Devices}).
16191 This does @emph{not} specify the keyboard layout used by the bootloader, nor
16192 that used by the graphical display server. @xref{Bootloader Configuration},
16193 for information on how to specify the bootloader's keyboard layout. @xref{X
16194 Window}, for information on how to specify the keyboard layout used by the X
16198 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
16200 @cindex initial RAM disk
16201 The list of Linux kernel modules that need to be available in the
16202 initial RAM disk. @xref{Initial RAM Disk}.
16204 @item @code{initrd} (default: @code{base-initrd})
16205 A procedure that returns an initial RAM disk for the Linux
16206 kernel. This field is provided to support low-level customization and
16207 should rarely be needed for casual use. @xref{Initial RAM Disk}.
16209 @item @code{firmware} (default: @code{%base-firmware})
16211 List of firmware packages loadable by the operating system kernel.
16213 The default includes firmware needed for Atheros- and Broadcom-based
16214 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
16215 respectively). @xref{Hardware Considerations}, for more info on
16216 supported hardware.
16218 @item @code{host-name}
16221 @item @code{hosts-file}
16223 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
16224 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
16225 Reference Manual}). The default is a file with entries for
16226 @code{localhost} and @var{host-name}.
16228 @item @code{mapped-devices} (default: @code{'()})
16229 A list of mapped devices. @xref{Mapped Devices}.
16231 @item @code{file-systems}
16232 A list of file systems. @xref{File Systems}.
16234 @item @code{swap-devices} (default: @code{'()})
16235 @cindex swap devices
16236 A list of swap spaces. @xref{Swap Space}.
16238 @item @code{users} (default: @code{%base-user-accounts})
16239 @itemx @code{groups} (default: @code{%base-groups})
16240 List of user accounts and groups. @xref{User Accounts}.
16242 If the @code{users} list lacks a user account with UID@tie{}0, a
16243 ``root'' account with UID@tie{}0 is automatically added.
16245 @item @code{skeletons} (default: @code{(default-skeletons)})
16246 A list of target file name/file-like object tuples (@pxref{G-Expressions,
16247 file-like objects}). These are the skeleton files that will be added to
16248 the home directory of newly-created user accounts.
16250 For instance, a valid value may look like this:
16253 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
16254 (".guile" ,(plain-file "guile"
16255 "(use-modules (ice-9 readline))
16256 (activate-readline)")))
16259 @item @code{issue} (default: @code{%default-issue})
16260 A string denoting the contents of the @file{/etc/issue} file, which is
16261 displayed when users log in on a text console.
16263 @item @code{packages} (default: @code{%base-packages})
16264 A list of packages to be installed in the global profile, which is accessible
16265 at @file{/run/current-system/profile}. Each element is either a package
16266 variable or a package/output tuple. Here's a simple example of both:
16269 (cons* git ; the default "out" output
16270 (list git "send-email") ; another output of git
16271 %base-packages) ; the default set
16274 The default set includes core utilities and it is good practice to
16275 install non-core utilities in user profiles (@pxref{Invoking guix
16278 @item @code{timezone}
16279 A timezone identifying string---e.g., @code{"Europe/Paris"}.
16281 You can run the @command{tzselect} command to find out which timezone
16282 string corresponds to your region. Choosing an invalid timezone name
16283 causes @command{guix system} to fail.
16285 @item @code{locale} (default: @code{"en_US.utf8"})
16286 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
16287 Library Reference Manual}). @xref{Locales}, for more information.
16289 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
16290 The list of locale definitions to be compiled and that may be used at
16291 run time. @xref{Locales}.
16293 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
16294 The list of GNU@tie{}libc packages whose locale data and tools are used
16295 to build the locale definitions. @xref{Locales}, for compatibility
16296 considerations that justify this option.
16298 @item @code{name-service-switch} (default: @code{%default-nss})
16299 Configuration of the libc name service switch (NSS)---a
16300 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
16303 @item @code{services} (default: @code{%base-services})
16304 A list of service objects denoting system services. @xref{Services}.
16306 @cindex essential services
16307 @item @code{essential-services} (default: ...)
16308 The list of ``essential services''---i.e., things like instances of
16309 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
16310 Reference}), which are derived from the operating system definition itself.
16311 As a user you should @emph{never} need to touch this field.
16313 @item @code{pam-services} (default: @code{(base-pam-services)})
16315 @cindex pluggable authentication modules
16316 Linux @dfn{pluggable authentication module} (PAM) services.
16317 @c FIXME: Add xref to PAM services section.
16319 @item @code{setuid-programs} (default: @code{%setuid-programs})
16320 List of @code{<setuid-program>}. @xref{Setuid Programs}, for more
16323 @item @code{sudoers-file} (default: @code{%sudoers-specification})
16324 @cindex sudoers file
16325 The contents of the @file{/etc/sudoers} file as a file-like object
16326 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
16328 This file specifies which users can use the @command{sudo} command, what
16329 they are allowed to do, and what privileges they may gain. The default
16330 is that only @code{root} and members of the @code{wheel} group may use
16335 @deffn {Scheme Syntax} this-operating-system
16336 When used in the @emph{lexical scope} of an operating system field definition,
16337 this identifier resolves to the operating system being defined.
16339 The example below shows how to refer to the operating system being defined in
16340 the definition of the @code{label} field:
16343 (use-modules (gnu) (guix))
16347 (label (package-full-name
16348 (operating-system-kernel this-operating-system))))
16351 It is an error to refer to @code{this-operating-system} outside an operating
16358 @section File Systems
16360 The list of file systems to be mounted is specified in the
16361 @code{file-systems} field of the operating system declaration
16362 (@pxref{Using the Configuration System}). Each file system is declared
16363 using the @code{file-system} form, like this:
16367 (mount-point "/home")
16368 (device "/dev/sda3")
16372 As usual, some of the fields are mandatory---those shown in the example
16373 above---while others can be omitted. These are described below.
16375 @deftp {Data Type} file-system
16376 Objects of this type represent file systems to be mounted. They
16377 contain the following members:
16381 This is a string specifying the type of the file system---e.g.,
16384 @item @code{mount-point}
16385 This designates the place where the file system is to be mounted.
16387 @item @code{device}
16388 This names the ``source'' of the file system. It can be one of three
16389 things: a file system label, a file system UUID, or the name of a
16390 @file{/dev} node. Labels and UUIDs offer a way to refer to file
16391 systems without having to hard-code their actual device
16392 name@footnote{Note that, while it is tempting to use
16393 @file{/dev/disk/by-uuid} and similar device names to achieve the same
16394 result, this is not recommended: These special device nodes are created
16395 by the udev daemon and may be unavailable at the time the device is
16398 @findex file-system-label
16399 File system labels are created using the @code{file-system-label}
16400 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
16401 plain strings. Here's an example of a file system referred to by its
16402 label, as shown by the @command{e2label} command:
16406 (mount-point "/home")
16408 (device (file-system-label "my-home")))
16412 UUIDs are converted from their string representation (as shown by the
16413 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
16414 @code{uuid} form expects 16-byte UUIDs as defined in
16415 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
16416 form of UUID used by the ext2 family of file systems and others, but it
16417 is different from ``UUIDs'' found in FAT file systems, for instance.},
16422 (mount-point "/home")
16424 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16427 When the source of a file system is a mapped device (@pxref{Mapped
16428 Devices}), its @code{device} field @emph{must} refer to the mapped
16429 device name---e.g., @file{"/dev/mapper/root-partition"}.
16430 This is required so that
16431 the system knows that mounting the file system depends on having the
16432 corresponding device mapping established.
16434 @item @code{flags} (default: @code{'()})
16435 This is a list of symbols denoting mount flags. Recognized flags
16436 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
16437 access to special files), @code{no-suid} (ignore setuid and setgid
16438 bits), @code{no-atime} (do not update file access times),
16439 @code{strict-atime} (update file access time), @code{lazy-time} (only
16440 update time on the in-memory version of the file inode),
16441 @code{no-exec} (disallow program execution), and @code{shared} (make the
16443 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
16444 Manual}, for more information on these flags.
16446 @item @code{options} (default: @code{#f})
16447 This is either @code{#f}, or a string denoting mount options passed to
16448 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
16449 Library Reference Manual}, for details.
16451 Run @command{man 8 mount} for options for various file systems, but
16452 beware that what it lists as file-system-independent ``mount options'' are
16453 in fact flags, and belong in the @code{flags} field described above.
16455 The @code{file-system-options->alist} and @code{alist->file-system-options}
16456 procedures from @code{(gnu system file-systems)} can be used to convert
16457 file system options given as an association list to the string
16458 representation, and vice-versa.
16460 @item @code{mount?} (default: @code{#t})
16461 This value indicates whether to automatically mount the file system when
16462 the system is brought up. When set to @code{#f}, the file system gets
16463 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
16464 is not automatically mounted.
16466 @item @code{needed-for-boot?} (default: @code{#f})
16467 This Boolean value indicates whether the file system is needed when
16468 booting. If that is true, then the file system is mounted when the
16469 initial RAM disk (initrd) is loaded. This is always the case, for
16470 instance, for the root file system.
16472 @item @code{check?} (default: @code{#t})
16473 This Boolean indicates whether the file system should be checked for
16474 errors before being mounted. How and when this happens can be further
16475 adjusted with the following options.
16477 @item @code{skip-check-if-clean?} (default: @code{#t})
16478 When true, this Boolean indicates that a file system check triggered
16479 by @code{check?} may exit early if the file system is marked as
16480 ``clean'', meaning that it was previously correctly unmounted and
16481 should not contain errors.
16483 Setting this to false will always force a full consistency check when
16484 @code{check?} is true. This may take a very long time and is not
16485 recommended on healthy systems---in fact, it may reduce reliability!
16487 Conversely, some primitive file systems like @code{fat} do not keep
16488 track of clean shutdowns and will perform a full scan regardless of the
16489 value of this option.
16491 @item @code{repair} (default: @code{'preen})
16492 When @code{check?} finds errors, it can (try to) repair them and
16493 continue booting. This option controls when and how to do so.
16495 If false, try not to modify the file system at all. Checking certain
16496 file systems like @code{jfs} may still write to the device to replay
16497 the journal. No repairs will be attempted.
16499 If @code{#t}, try to repair any errors found and assume ``yes'' to
16500 all questions. This will fix the most errors, but may be risky.
16502 If @code{'preen}, repair only errors that are safe to fix without
16503 human interaction. What that means is left up to the developers of
16504 each file system and may be equivalent to ``none'' or ``all''.
16506 @item @code{create-mount-point?} (default: @code{#f})
16507 When true, the mount point is created if it does not exist yet.
16509 @item @code{mount-may-fail?} (default: @code{#f})
16510 When true, this indicates that mounting this file system can fail but
16511 that should not be considered an error. This is useful in unusual
16512 cases; an example of this is @code{efivarfs}, a file system that can
16513 only be mounted on EFI/UEFI systems.
16515 @item @code{dependencies} (default: @code{'()})
16516 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
16517 representing file systems that must be mounted or mapped devices that
16518 must be opened before (and unmounted or closed after) this one.
16520 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
16521 a dependency of @file{/sys/fs/cgroup/cpu} and
16522 @file{/sys/fs/cgroup/memory}.
16524 Another example is a file system that depends on a mapped device, for
16525 example for an encrypted partition (@pxref{Mapped Devices}).
16529 @deffn {Scheme Procedure} file-system-label @var{str}
16530 This procedure returns an opaque file system label from @var{str}, a
16534 (file-system-label "home")
16535 @result{} #<file-system-label "home">
16538 File system labels are used to refer to file systems by label rather
16539 than by device name. See above for examples.
16542 The @code{(gnu system file-systems)} exports the following useful
16545 @defvr {Scheme Variable} %base-file-systems
16546 These are essential file systems that are required on normal systems,
16547 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
16548 below). Operating system declarations should always contain at least
16552 @defvr {Scheme Variable} %pseudo-terminal-file-system
16553 This is the file system to be mounted as @file{/dev/pts}. It supports
16554 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
16555 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
16556 Manual}). Pseudo-terminals are used by terminal emulators such as
16560 @defvr {Scheme Variable} %shared-memory-file-system
16561 This file system is mounted as @file{/dev/shm} and is used to support
16562 memory sharing across processes (@pxref{Memory-mapped I/O,
16563 @code{shm_open},, libc, The GNU C Library Reference Manual}).
16566 @defvr {Scheme Variable} %immutable-store
16567 This file system performs a read-only ``bind mount'' of
16568 @file{/gnu/store}, making it read-only for all the users including
16569 @code{root}. This prevents against accidental modification by software
16570 running as @code{root} or by system administrators.
16572 The daemon itself is still able to write to the store: it remounts it
16573 read-write in its own ``name space.''
16576 @defvr {Scheme Variable} %binary-format-file-system
16577 The @code{binfmt_misc} file system, which allows handling of arbitrary
16578 executable file types to be delegated to user space. This requires the
16579 @code{binfmt.ko} kernel module to be loaded.
16582 @defvr {Scheme Variable} %fuse-control-file-system
16583 The @code{fusectl} file system, which allows unprivileged users to mount
16584 and unmount user-space FUSE file systems. This requires the
16585 @code{fuse.ko} kernel module to be loaded.
16588 The @code{(gnu system uuid)} module provides tools to deal with file
16589 system ``unique identifiers'' (UUIDs).
16591 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
16592 Return an opaque UUID (unique identifier) object of the given @var{type}
16593 (a symbol) by parsing @var{str} (a string):
16596 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
16597 @result{} #<<uuid> type: dce bv: @dots{}>
16599 (uuid "1234-ABCD" 'fat)
16600 @result{} #<<uuid> type: fat bv: @dots{}>
16603 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
16604 @code{ntfs}, or one of the commonly found synonyms for these.
16606 UUIDs are another way to unambiguously refer to file systems in
16607 operating system configuration. See the examples above.
16611 @node Btrfs file system
16612 @subsection Btrfs file system
16614 The Btrfs has special features, such as subvolumes, that merit being
16615 explained in more details. The following section attempts to cover
16616 basic as well as complex uses of a Btrfs file system with the Guix
16619 In its simplest usage, a Btrfs file system can be described, for
16624 (mount-point "/home")
16626 (device (file-system-label "my-home")))
16629 The example below is more complex, as it makes use of a Btrfs
16630 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
16631 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
16632 dependency on @code{mapped-devices}):
16636 (device (file-system-label "my-btrfs-pool"))
16639 (options "subvol=rootfs")
16640 (dependencies mapped-devices))
16643 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
16644 top level during the early boot, and rely on their configuration to
16645 refer to the correct subvolume path within that top level. The
16646 bootloaders operating in this way typically produce their configuration
16647 on a running system where the Btrfs partitions are already mounted and
16648 where the subvolume information is readily available. As an example,
16649 @command{grub-mkconfig}, the configuration generator command shipped
16650 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
16651 path of a subvolume.
16653 The Guix System produces a bootloader configuration using the operating
16654 system configuration as its sole input; it is therefore necessary to
16655 extract the subvolume name on which @file{/gnu/store} lives (if any)
16656 from that operating system configuration. To better illustrate,
16657 consider a subvolume named 'rootfs' which contains the root file system
16658 data. In such situation, the GRUB bootloader would only see the top
16659 level of the root Btrfs partition, e.g.:
16663 ├── rootfs (subvolume directory)
16664 ├── gnu (normal directory)
16665 ├── store (normal directory)
16669 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
16670 of the kernel, initrd binaries and any other files referred to in the
16671 GRUB configuration that must be found during the early boot.
16673 The next example shows a nested hierarchy of subvolumes and
16678 ├── rootfs (subvolume)
16679 ├── gnu (normal directory)
16680 ├── store (subvolume)
16684 This scenario would work without mounting the 'store' subvolume.
16685 Mounting 'rootfs' is sufficient, since the subvolume name matches its
16686 intended mount point in the file system hierarchy. Alternatively, the
16687 'store' subvolume could be referred to by setting the @code{subvol}
16688 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
16690 Finally, a more contrived example of nested subvolumes:
16694 ├── root-snapshots (subvolume)
16695 ├── root-current (subvolume)
16696 ├── guix-store (subvolume)
16700 Here, the 'guix-store' subvolume doesn't match its intended mount point,
16701 so it is necessary to mount it. The subvolume must be fully specified,
16702 by passing its file name to the @code{subvol} option. To illustrate,
16703 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
16704 a file system declaration such as:
16708 (device (file-system-label "btrfs-pool-1"))
16709 (mount-point "/gnu/store")
16711 (options "subvol=root-snapshots/root-current/guix-store,\
16712 compress-force=zstd,space_cache=v2"))
16715 @node Mapped Devices
16716 @section Mapped Devices
16718 @cindex device mapping
16719 @cindex mapped devices
16720 The Linux kernel has a notion of @dfn{device mapping}: a block device,
16721 such as a hard disk partition, can be @dfn{mapped} into another device,
16722 usually in @code{/dev/mapper/},
16723 with additional processing over the data that flows through
16724 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
16725 concept of a ``mapped device'' and that of a file system: both boil down
16726 to @emph{translating} input/output operations made on a file to
16727 operations on its backing store. Thus, the Hurd implements mapped
16728 devices, like file systems, using the generic @dfn{translator} mechanism
16729 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
16730 typical example is encryption device mapping: all writes to the mapped
16731 device are encrypted, and all reads are deciphered, transparently.
16732 Guix extends this notion by considering any device or set of devices that
16733 are @dfn{transformed} in some way to create a new device; for instance,
16734 RAID devices are obtained by @dfn{assembling} several other devices, such
16735 as hard disks or partitions, into a new one that behaves as one partition.
16737 Mapped devices are declared using the @code{mapped-device} form,
16738 defined as follows; for examples, see below.
16740 @deftp {Data Type} mapped-device
16741 Objects of this type represent device mappings that will be made when
16742 the system boots up.
16746 This is either a string specifying the name of the block device to be mapped,
16747 such as @code{"/dev/sda3"}, or a list of such strings when several devices
16748 need to be assembled for creating a new one. In case of LVM this is a
16749 string specifying name of the volume group to be mapped.
16752 This string specifies the name of the resulting mapped device. For
16753 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
16754 specifying @code{"my-partition"} leads to the creation of
16755 the @code{"/dev/mapper/my-partition"} device.
16756 For RAID devices of type @code{raid-device-mapping}, the full device name
16757 such as @code{"/dev/md0"} needs to be given.
16758 LVM logical volumes of type @code{lvm-device-mapping} need to
16759 be specified as @code{"VGNAME-LVNAME"}.
16762 This list of strings specifies names of the resulting mapped devices in case
16763 there are several. The format is identical to @var{target}.
16766 This must be a @code{mapped-device-kind} object, which specifies how
16767 @var{source} is mapped to @var{target}.
16771 @defvr {Scheme Variable} luks-device-mapping
16772 This defines LUKS block device encryption using the @command{cryptsetup}
16773 command from the package with the same name. It relies on the
16774 @code{dm-crypt} Linux kernel module.
16777 @defvr {Scheme Variable} raid-device-mapping
16778 This defines a RAID device, which is assembled using the @code{mdadm}
16779 command from the package with the same name. It requires a Linux kernel
16780 module for the appropriate RAID level to be loaded, such as @code{raid456}
16781 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
16784 @cindex LVM, logical volume manager
16785 @defvr {Scheme Variable} lvm-device-mapping
16786 This defines one or more logical volumes for the Linux
16787 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
16788 The volume group is activated by the @command{vgchange} command from the
16789 @code{lvm2} package.
16792 @cindex disk encryption
16794 The following example specifies a mapping from @file{/dev/sda3} to
16795 @file{/dev/mapper/home} using LUKS---the
16796 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
16797 standard mechanism for disk encryption.
16798 The @file{/dev/mapper/home}
16799 device can then be used as the @code{device} of a @code{file-system}
16800 declaration (@pxref{File Systems}).
16804 (source "/dev/sda3")
16806 (type luks-device-mapping))
16809 Alternatively, to become independent of device numbering, one may obtain
16810 the LUKS UUID (@dfn{unique identifier}) of the source device by a
16814 cryptsetup luksUUID /dev/sda3
16817 and use it as follows:
16821 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
16823 (type luks-device-mapping))
16826 @cindex swap encryption
16827 It is also desirable to encrypt swap space, since swap space may contain
16828 sensitive data. One way to accomplish that is to use a swap file in a
16829 file system on a device mapped via LUKS encryption. In this way, the
16830 swap file is encrypted because the entire device is encrypted.
16831 @xref{Swap Space}, or @xref{Preparing for Installation,,Disk
16832 Partitioning}, for an example.
16834 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
16835 may be declared as follows:
16839 (source (list "/dev/sda1" "/dev/sdb1"))
16840 (target "/dev/md0")
16841 (type raid-device-mapping))
16844 The @file{/dev/md0} device can then be used as the @code{device} of a
16845 @code{file-system} declaration (@pxref{File Systems}).
16846 Note that the RAID level need not be given; it is chosen during the
16847 initial creation and formatting of the RAID device and is determined
16848 automatically later.
16850 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
16851 be declared as follows:
16856 (targets (list "vg0-alpha" "vg0-beta"))
16857 (type lvm-device-mapping))
16860 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
16861 then be used as the @code{device} of a @code{file-system} declaration
16862 (@pxref{File Systems}).
16865 @section Swap Space
16868 Swap space, as it is commonly called, is a disk area specifically
16869 designated for paging: the process in charge of memory management
16870 (the Linux kernel or Hurd's default pager) can decide that some memory
16871 pages stored in RAM which belong to a running program but are unused
16872 should be stored on disk instead. It unloads those from the RAM,
16873 freeing up precious fast memory, and writes them to the swap space. If
16874 the program tries to access that very page, the memory management
16875 process loads it back into memory for the program to use.
16877 A common misconception about swap is that it is only useful when small
16878 amounts of RAM are available to the system. However, it should be noted
16879 that kernels often use all available RAM for disk access caching to make
16880 I/O faster, and thus paging out unused portions of program memory will
16881 expand the RAM available for such caching.
16883 For a more detailed description of how memory is managed from the
16884 viewpoint of a monolithic kernel, @xref{Memory
16885 Concepts,,, libc, The GNU C Library Reference Manual}.
16887 The Linux kernel has support for swap partitions and swap files: the
16888 former uses a whole disk partition for paging, whereas the second uses a
16889 file on a file system for that (the file system driver needs to support
16890 it). On a comparable setup, both have the same performance, so one
16891 should consider ease of use when deciding between them. Partitions are
16892 ``simpler'' and do not need file system support, but need to be
16893 allocated at disk formatting time (logical volumes notwithstanding),
16894 whereas files can be allocated and deallocated at any time.
16896 Note that swap space is not zeroed on shutdown, so sensitive data (such
16897 as passwords) may linger on it if it was paged out. As such, you should
16898 consider having your swap reside on an encrypted device (@pxref{Mapped
16901 @deftp {Data Type} swap-space
16902 Objects of this type represent swap spaces. They contain the following
16906 @item @code{target}
16907 The device or file to use, either a UUID, a @code{file-system-label} or
16908 a string, as in the definition of a @code{file-system} (@pxref{File
16911 @item @code{dependencies} (default: @code{'()})
16912 A list of @code{file-system} or @code{mapped-device} objects, upon which
16913 the availability of the space depends. Note that just like for
16914 @code{file-system} objects, dependencies which are needed for boot and
16915 mounted in early userspace are not managed by the Shepherd, and so
16916 automatically filtered out for you.
16918 @item @code{priority} (default: @code{#f})
16919 Only supported by the Linux kernel. Either @code{#f} to disable swap
16920 priority, or an integer between 0 and 32767. The kernel will first use
16921 swap spaces of higher priority when paging, and use same priority spaces
16922 on a round-robin basis. The kernel will use swap spaces without a set
16923 priority after prioritized spaces, and in the order that they appeared in
16926 @item @code{discard?} (default: @code{#f})
16927 Only supported by the Linux kernel. When true, the kernel will notify
16928 the disk controller of discarded pages, for example with the TRIM
16929 operation on Solid State Drives.
16934 Here are some examples:
16937 (swap-space (target (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16940 Use the swap partition with the given UUID@. You can learn the UUID of a
16941 Linux swap partition by running @command{swaplabel @var{device}}, where
16942 @var{device} is the @file{/dev} file name of that partition.
16946 (target (file-system-label "swap"))
16947 (dependencies mapped-devices))
16950 Use the partition with label @code{swap}, which can be found after all
16951 the @var{mapped-devices} mapped devices have been opened. Again, the
16952 @command{swaplabel} command allows you to view and change the label of a
16953 Linux swap partition.
16955 Here's a more involved example with the corresponding @code{file-systems} part
16956 of an @code{operating-system} declaration.
16961 (device (file-system-label "root"))
16965 (device (file-system-label "btrfs"))
16966 (mount-point "/btrfs")
16972 (target "/btrfs/swapfile")
16973 (dependencies (filter (file-system-mount-point-predicate "/btrfs")
16977 Use the file @file{/btrfs/swapfile} as swap space, which depends on the
16978 file system mounted at @file{/btrfs}. Note how we use Guile's filter to
16979 select the file system in an elegant fashion!
16981 @node User Accounts
16982 @section User Accounts
16986 @cindex user accounts
16987 User accounts and groups are entirely managed through the
16988 @code{operating-system} declaration. They are specified with the
16989 @code{user-account} and @code{user-group} forms:
16995 (supplementary-groups '("wheel" ;allow use of sudo, etc.
16996 "audio" ;sound card
16997 "video" ;video devices such as webcams
16998 "cdrom")) ;the good ol' CD-ROM
16999 (comment "Bob's sister"))
17002 Here's a user account that uses a different shell and a custom home
17003 directory (the default would be @file{"/home/bob"}):
17009 (comment "Alice's bro")
17010 (shell (file-append zsh "/bin/zsh"))
17011 (home-directory "/home/robert"))
17014 When booting or upon completion of @command{guix system reconfigure},
17015 the system ensures that only the user accounts and groups specified in
17016 the @code{operating-system} declaration exist, and with the specified
17017 properties. Thus, account or group creations or modifications made by
17018 directly invoking commands such as @command{useradd} are lost upon
17019 reconfiguration or reboot. This ensures that the system remains exactly
17022 @deftp {Data Type} user-account
17023 Objects of this type represent user accounts. The following members may
17028 The name of the user account.
17032 This is the name (a string) or identifier (a number) of the user group
17033 this account belongs to.
17035 @item @code{supplementary-groups} (default: @code{'()})
17036 Optionally, this can be defined as a list of group names that this
17037 account belongs to.
17039 @item @code{uid} (default: @code{#f})
17040 This is the user ID for this account (a number), or @code{#f}. In the
17041 latter case, a number is automatically chosen by the system when the
17042 account is created.
17044 @item @code{comment} (default: @code{""})
17045 A comment about the account, such as the account owner's full name.
17047 Note that, for non-system accounts, users are free to change their real
17048 name as it appears in @file{/etc/passwd} using the @command{chfn}
17049 command. When they do, their choice prevails over the system
17050 administrator's choice; reconfiguring does @emph{not} change their name.
17052 @item @code{home-directory}
17053 This is the name of the home directory for the account.
17055 @item @code{create-home-directory?} (default: @code{#t})
17056 Indicates whether the home directory of this account should be created
17057 if it does not exist yet.
17059 @item @code{shell} (default: Bash)
17060 This is a G-expression denoting the file name of a program to be used as
17061 the shell (@pxref{G-Expressions}). For example, you would refer to the
17062 Bash executable like this:
17065 (file-append bash "/bin/bash")
17069 ... and to the Zsh executable like that:
17072 (file-append zsh "/bin/zsh")
17075 @item @code{system?} (default: @code{#f})
17076 This Boolean value indicates whether the account is a ``system''
17077 account. System accounts are sometimes treated specially; for instance,
17078 graphical login managers do not list them.
17080 @anchor{user-account-password}
17081 @cindex password, for user accounts
17082 @item @code{password} (default: @code{#f})
17083 You would normally leave this field to @code{#f}, initialize user
17084 passwords as @code{root} with the @command{passwd} command, and then let
17085 users change it with @command{passwd}. Passwords set with
17086 @command{passwd} are of course preserved across reboot and
17089 If you @emph{do} want to set an initial password for an account, then
17090 this field must contain the encrypted password, as a string. You can use the
17091 @code{crypt} procedure for this purpose:
17098 ;; Specify a SHA-512-hashed initial password.
17099 (password (crypt "InitialPassword!" "$6$abc")))
17103 The hash of this initial password will be available in a file in
17104 @file{/gnu/store}, readable by all the users, so this method must be used with
17108 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
17109 more information on password encryption, and @ref{Encryption,,, guile, GNU
17110 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
17116 User group declarations are even simpler:
17119 (user-group (name "students"))
17122 @deftp {Data Type} user-group
17123 This type is for, well, user groups. There are just a few fields:
17127 The name of the group.
17129 @item @code{id} (default: @code{#f})
17130 The group identifier (a number). If @code{#f}, a new number is
17131 automatically allocated when the group is created.
17133 @item @code{system?} (default: @code{#f})
17134 This Boolean value indicates whether the group is a ``system'' group.
17135 System groups have low numerical IDs.
17137 @item @code{password} (default: @code{#f})
17138 What, user groups can have a password? Well, apparently yes. Unless
17139 @code{#f}, this field specifies the password of the group.
17144 For convenience, a variable lists all the basic user groups one may
17147 @defvr {Scheme Variable} %base-groups
17148 This is the list of basic user groups that users and/or packages expect
17149 to be present on the system. This includes groups such as ``root'',
17150 ``wheel'', and ``users'', as well as groups used to control access to
17151 specific devices such as ``audio'', ``disk'', and ``cdrom''.
17154 @defvr {Scheme Variable} %base-user-accounts
17155 This is the list of basic system accounts that programs may expect to
17156 find on a GNU/Linux system, such as the ``nobody'' account.
17158 Note that the ``root'' account is not included here. It is a
17159 special-case and is automatically added whether or not it is specified.
17162 @node Keyboard Layout
17163 @section Keyboard Layout
17165 @cindex keyboard layout
17167 To specify what each key of your keyboard does, you need to tell the operating
17168 system what @dfn{keyboard layout} you want to use. The default, when nothing
17169 is specified, is the US English QWERTY layout for 105-key PC keyboards.
17170 However, German speakers will usually prefer the German QWERTZ layout, French
17171 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
17172 or bépo, and they might even want to further customize the effect of some of
17173 the keys. This section explains how to get that done.
17175 @cindex keyboard layout, definition
17176 There are three components that will want to know about your keyboard layout:
17180 The @emph{bootloader} may want to know what keyboard layout you want to use
17181 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
17182 you want, for instance, to make sure that you can type the passphrase of your
17183 encrypted root partition using the right layout.
17186 The @emph{operating system kernel}, Linux, will need that so that the console
17187 is properly configured (@pxref{operating-system Reference,
17188 @code{keyboard-layout}}).
17191 The @emph{graphical display server}, usually Xorg, also has its own idea of
17192 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
17195 Guix allows you to configure all three separately but, fortunately, it allows
17196 you to share the same keyboard layout for all three components.
17198 @cindex XKB, keyboard layouts
17199 Keyboard layouts are represented by records created by the
17200 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
17201 the X Keyboard extension (XKB), each layout has four attributes: a name (often
17202 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
17203 optional variant name, an optional keyboard model name, and a possibly empty
17204 list of additional options. In most cases the layout name is all you care
17207 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
17208 [#:model] [#:options '()]
17209 Return a new keyboard layout with the given @var{name} and @var{variant}.
17211 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
17212 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
17213 @code{xkeyboard-config} package for valid options.
17216 Here are a few examples:
17219 ;; The German QWERTZ layout. Here we assume a standard
17220 ;; "pc105" keyboard model.
17221 (keyboard-layout "de")
17223 ;; The bépo variant of the French layout.
17224 (keyboard-layout "fr" "bepo")
17226 ;; The Catalan layout.
17227 (keyboard-layout "es" "cat")
17229 ;; Arabic layout with "Alt-Shift" to switch to US layout.
17230 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
17232 ;; The Latin American Spanish layout. In addition, the
17233 ;; "Caps Lock" key is used as an additional "Ctrl" key,
17234 ;; and the "Menu" key is used as a "Compose" key to enter
17235 ;; accented letters.
17236 (keyboard-layout "latam"
17237 #:options '("ctrl:nocaps" "compose:menu"))
17239 ;; The Russian layout for a ThinkPad keyboard.
17240 (keyboard-layout "ru" #:model "thinkpad")
17242 ;; The "US international" layout, which is the US layout plus
17243 ;; dead keys to enter accented characters. This is for an
17244 ;; Apple MacBook keyboard.
17245 (keyboard-layout "us" "intl" #:model "macbook78")
17248 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
17249 for a complete list of supported layouts, variants, and models.
17251 @cindex keyboard layout, configuration
17252 Let's say you want your system to use the Turkish keyboard layout throughout
17253 your system---bootloader, console, and Xorg. Here's what your system
17254 configuration would look like:
17256 @findex set-xorg-configuration
17258 ;; Using the Turkish layout for the bootloader, the console,
17263 (keyboard-layout (keyboard-layout "tr")) ;for the console
17264 (bootloader (bootloader-configuration
17265 (bootloader grub-efi-bootloader)
17266 (targets '("/boot/efi"))
17267 (keyboard-layout keyboard-layout))) ;for GRUB
17268 (services (cons (set-xorg-configuration
17269 (xorg-configuration ;for Xorg
17270 (keyboard-layout keyboard-layout)))
17271 %desktop-services)))
17274 In the example above, for GRUB and for Xorg, we just refer to the
17275 @code{keyboard-layout} field defined above, but we could just as well refer to
17276 a different layout. The @code{set-xorg-configuration} procedure communicates
17277 the desired Xorg configuration to the graphical log-in manager, by default
17280 We've discussed how to specify the @emph{default} keyboard layout of your
17281 system when it starts, but you can also adjust it at run time:
17285 If you're using GNOME, its settings panel has a ``Region & Language'' entry
17286 where you can select one or more keyboard layouts.
17289 Under Xorg, the @command{setxkbmap} command (from the same-named package)
17290 allows you to change the current layout. For example, this is how you would
17291 change the layout to US Dvorak:
17294 setxkbmap us dvorak
17298 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
17299 console. However, note that @code{loadkeys} does @emph{not} use the XKB
17300 keyboard layout categorization described above. The command below loads the
17301 French bépo layout:
17312 A @dfn{locale} defines cultural conventions for a particular language
17313 and region of the world (@pxref{Locales,,, libc, The GNU C Library
17314 Reference Manual}). Each locale has a name that typically has the form
17315 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
17316 @code{fr_LU.utf8} designates the locale for the French language, with
17317 cultural conventions from Luxembourg, and using the UTF-8 encoding.
17319 @cindex locale definition
17320 Usually, you will want to specify the default locale for the machine
17321 using the @code{locale} field of the @code{operating-system} declaration
17322 (@pxref{operating-system Reference, @code{locale}}).
17324 The selected locale is automatically added to the @dfn{locale
17325 definitions} known to the system if needed, with its codeset inferred
17326 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
17327 @code{UTF-8} codeset. Additional locale definitions can be specified in
17328 the @code{locale-definitions} slot of @code{operating-system}---this is
17329 useful, for instance, if the codeset could not be inferred from the
17330 locale name. The default set of locale definitions includes some widely
17331 used locales, but not all the available locales, in order to save space.
17333 For instance, to add the North Frisian locale for Germany, the value of
17337 (cons (locale-definition
17338 (name "fy_DE.utf8") (source "fy_DE"))
17339 %default-locale-definitions)
17342 Likewise, to save space, one might want @code{locale-definitions} to
17343 list only the locales that are actually used, as in:
17346 (list (locale-definition
17347 (name "ja_JP.eucjp") (source "ja_JP")
17348 (charset "EUC-JP")))
17352 The compiled locale definitions are available at
17353 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
17354 version, which is the default location where the GNU@tie{}libc provided
17355 by Guix looks for locale data. This can be overridden using the
17356 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
17357 @env{LOCPATH} and locale packages}).
17359 The @code{locale-definition} form is provided by the @code{(gnu system
17360 locale)} module. Details are given below.
17362 @deftp {Data Type} locale-definition
17363 This is the data type of a locale definition.
17368 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
17369 Reference Manual}, for more information on locale names.
17371 @item @code{source}
17372 The name of the source for that locale. This is typically the
17373 @code{@var{language}_@var{territory}} part of the locale name.
17375 @item @code{charset} (default: @code{"UTF-8"})
17376 The ``character set'' or ``code set'' for that locale,
17377 @uref{https://www.iana.org/assignments/character-sets, as defined by
17383 @defvr {Scheme Variable} %default-locale-definitions
17384 A list of commonly used UTF-8 locales, used as the default
17385 value of the @code{locale-definitions} field of @code{operating-system}
17388 @cindex locale name
17389 @cindex normalized codeset in locale names
17390 These locale definitions use the @dfn{normalized codeset} for the part
17391 that follows the dot in the name (@pxref{Using gettextized software,
17392 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
17393 instance it has @code{uk_UA.utf8} but @emph{not}, say,
17394 @code{uk_UA.UTF-8}.
17397 @subsection Locale Data Compatibility Considerations
17399 @cindex incompatibility, of locale data
17400 @code{operating-system} declarations provide a @code{locale-libcs} field
17401 to specify the GNU@tie{}libc packages that are used to compile locale
17402 declarations (@pxref{operating-system Reference}). ``Why would I
17403 care?'', you may ask. Well, it turns out that the binary format of
17404 locale data is occasionally incompatible from one libc version to
17407 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
17408 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
17409 For instance, a program linked against libc version 2.21 is unable to
17410 read locale data produced with libc 2.22; worse, that program
17411 @emph{aborts} instead of simply ignoring the incompatible locale
17412 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
17413 the incompatible locale data, which is already an improvement.}.
17414 Similarly, a program linked against libc 2.22 can read most, but not
17415 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
17416 data is incompatible); thus calls to @code{setlocale} may fail, but
17417 programs will not abort.
17419 The ``problem'' with Guix is that users have a lot of freedom: They can
17420 choose whether and when to upgrade software in their profiles, and might
17421 be using a libc version different from the one the system administrator
17422 used to build the system-wide locale data.
17424 Fortunately, unprivileged users can also install their own locale data
17425 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
17426 @env{GUIX_LOCPATH} and locale packages}).
17428 Still, it is best if the system-wide locale data at
17429 @file{/run/current-system/locale} is built for all the libc versions
17430 actually in use on the system, so that all the programs can access
17431 it---this is especially crucial on a multi-user system. To do that, the
17432 administrator can specify several libc packages in the
17433 @code{locale-libcs} field of @code{operating-system}:
17436 (use-package-modules base)
17440 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
17443 This example would lead to a system containing locale definitions for
17444 both libc 2.21 and the current version of libc in
17445 @file{/run/current-system/locale}.
17451 @cindex system services
17452 An important part of preparing an @code{operating-system} declaration is
17453 listing @dfn{system services} and their configuration (@pxref{Using the
17454 Configuration System}). System services are typically daemons launched
17455 when the system boots, or other actions needed at that time---e.g.,
17456 configuring network access.
17458 Guix has a broad definition of ``service'' (@pxref{Service
17459 Composition}), but many services are managed by the GNU@tie{}Shepherd
17460 (@pxref{Shepherd Services}). On a running system, the @command{herd}
17461 command allows you to list the available services, show their status,
17462 start and stop them, or do other specific operations (@pxref{Jump
17463 Start,,, shepherd, The GNU Shepherd Manual}). For example:
17469 The above command, run as @code{root}, lists the currently defined
17470 services. The @command{herd doc} command shows a synopsis of the given
17471 service and its associated actions:
17475 Run libc's name service cache daemon (nscd).
17477 # herd doc nscd action invalidate
17478 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
17481 The @command{start}, @command{stop}, and @command{restart} sub-commands
17482 have the effect you would expect. For instance, the commands below stop
17483 the nscd service and restart the Xorg display server:
17487 Service nscd has been stopped.
17488 # herd restart xorg-server
17489 Service xorg-server has been stopped.
17490 Service xorg-server has been started.
17493 The following sections document the available services, starting with
17494 the core services, that may be used in an @code{operating-system}
17498 * Base Services:: Essential system services.
17499 * Scheduled Job Execution:: The mcron service.
17500 * Log Rotation:: The rottlog service.
17501 * Networking Setup:: Setting up network interfaces.
17502 * Networking Services:: Firewall, SSH daemon, etc.
17503 * Unattended Upgrades:: Automated system upgrades.
17504 * X Window:: Graphical display.
17505 * Printing Services:: Local and remote printer support.
17506 * Desktop Services:: D-Bus and desktop services.
17507 * Sound Services:: ALSA and Pulseaudio services.
17508 * Database Services:: SQL databases, key-value stores, etc.
17509 * Mail Services:: IMAP, POP3, SMTP, and all that.
17510 * Messaging Services:: Messaging services.
17511 * Telephony Services:: Telephony services.
17512 * File-Sharing Services:: File-sharing services.
17513 * Monitoring Services:: Monitoring services.
17514 * Kerberos Services:: Kerberos services.
17515 * LDAP Services:: LDAP services.
17516 * Web Services:: Web servers.
17517 * Certificate Services:: TLS certificates via Let's Encrypt.
17518 * DNS Services:: DNS daemons.
17519 * VPN Services:: VPN daemons.
17520 * Network File System:: NFS related services.
17521 * Samba Services:: Samba services.
17522 * Continuous Integration:: Cuirass and Laminar services.
17523 * Power Management Services:: Extending battery life.
17524 * Audio Services:: The MPD.
17525 * Virtualization Services:: Virtualization services.
17526 * Version Control Services:: Providing remote access to Git repositories.
17527 * Game Services:: Game servers.
17528 * PAM Mount Service:: Service to mount volumes when logging in.
17529 * Guix Services:: Services relating specifically to Guix.
17530 * Linux Services:: Services tied to the Linux kernel.
17531 * Hurd Services:: Services specific for a Hurd System.
17532 * Miscellaneous Services:: Other services.
17535 @node Base Services
17536 @subsection Base Services
17538 The @code{(gnu services base)} module provides definitions for the basic
17539 services that one expects from the system. The services exported by
17540 this module are listed below.
17542 @defvr {Scheme Variable} %base-services
17543 This variable contains a list of basic services (@pxref{Service Types
17544 and Services}, for more information on service objects) one would
17545 expect from the system: a login service (mingetty) on each tty, syslogd,
17546 the libc name service cache daemon (nscd), the udev device manager, and
17549 This is the default value of the @code{services} field of
17550 @code{operating-system} declarations. Usually, when customizing a
17551 system, you will want to append services to @code{%base-services}, like
17555 (append (list (service avahi-service-type)
17556 (service openssh-service-type))
17561 @defvr {Scheme Variable} special-files-service-type
17562 This is the service that sets up ``special files'' such as
17563 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
17565 The value associated with @code{special-files-service-type} services
17566 must be a list of tuples where the first element is the ``special file''
17567 and the second element is its target. By default it is:
17569 @cindex @file{/bin/sh}
17570 @cindex @file{sh}, in @file{/bin}
17572 `(("/bin/sh" ,(file-append bash "/bin/sh")))
17575 @cindex @file{/usr/bin/env}
17576 @cindex @file{env}, in @file{/usr/bin}
17577 If you want to add, say, @code{/usr/bin/env} to your system, you can
17581 `(("/bin/sh" ,(file-append bash "/bin/sh"))
17582 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
17585 Since this is part of @code{%base-services}, you can use
17586 @code{modify-services} to customize the set of special files
17587 (@pxref{Service Reference, @code{modify-services}}). But the simple way
17588 to add a special file is @i{via} the @code{extra-special-file} procedure
17592 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
17593 Use @var{target} as the ``special file'' @var{file}.
17595 For example, adding the following lines to the @code{services} field of
17596 your operating system declaration leads to a @file{/usr/bin/env}
17600 (extra-special-file "/usr/bin/env"
17601 (file-append coreutils "/bin/env"))
17605 @deffn {Scheme Procedure} host-name-service @var{name}
17606 Return a service that sets the host name to @var{name}.
17609 @defvr {Scheme Variable} console-font-service-type
17610 Install the given fonts on the specified ttys (fonts are per
17611 virtual console on the kernel Linux). The value of this service is a list of
17612 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
17613 package or any valid argument to @command{setfont}, as in this example:
17616 `(("tty1" . "LatGrkCyr-8x16")
17617 ("tty2" . ,(file-append
17619 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
17620 ("tty3" . ,(file-append
17622 "/share/consolefonts/ter-132n"))) ; for HDPI
17626 @deffn {Scheme Procedure} login-service @var{config}
17627 Return a service to run login according to @var{config}, a
17628 @code{<login-configuration>} object, which specifies the message of the day,
17629 among other things.
17632 @deftp {Data Type} login-configuration
17633 This is the data type representing the configuration of login.
17638 @cindex message of the day
17639 A file-like object containing the ``message of the day''.
17641 @item @code{allow-empty-passwords?} (default: @code{#t})
17642 Allow empty passwords by default so that first-time users can log in when
17643 the 'root' account has just been created.
17648 @deffn {Scheme Procedure} mingetty-service @var{config}
17649 Return a service to run mingetty according to @var{config}, a
17650 @code{<mingetty-configuration>} object, which specifies the tty to run, among
17654 @deftp {Data Type} mingetty-configuration
17655 This is the data type representing the configuration of Mingetty, which
17656 provides the default implementation of virtual console log-in.
17661 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
17663 @item @code{auto-login} (default: @code{#f})
17664 When true, this field must be a string denoting the user name under
17665 which the system automatically logs in. When it is @code{#f}, a
17666 user name and password must be entered to log in.
17668 @item @code{login-program} (default: @code{#f})
17669 This must be either @code{#f}, in which case the default log-in program
17670 is used (@command{login} from the Shadow tool suite), or a gexp denoting
17671 the name of the log-in program.
17673 @item @code{login-pause?} (default: @code{#f})
17674 When set to @code{#t} in conjunction with @var{auto-login}, the user
17675 will have to press a key before the log-in shell is launched.
17677 @item @code{clear-on-logout?} (default: @code{#t})
17678 When set to @code{#t}, the screen will be cleared after logout.
17680 @item @code{mingetty} (default: @var{mingetty})
17681 The Mingetty package to use.
17686 @deffn {Scheme Procedure} agetty-service @var{config}
17687 Return a service to run agetty according to @var{config}, an
17688 @code{<agetty-configuration>} object, which specifies the tty to run,
17689 among other things.
17692 @deftp {Data Type} agetty-configuration
17693 This is the data type representing the configuration of agetty, which
17694 implements virtual and serial console log-in. See the @code{agetty(8)}
17695 man page for more information.
17700 The name of the console this agetty runs on, as a string---e.g.,
17701 @code{"ttyS0"}. This argument is optional, it will default to
17702 a reasonable default serial port used by the kernel Linux.
17704 For this, if there is a value for an option @code{agetty.tty} in the kernel
17705 command line, agetty will extract the device name of the serial port
17706 from it and use that.
17708 If not and if there is a value for an option @code{console} with a tty in
17709 the Linux command line, agetty will extract the device name of the
17710 serial port from it and use that.
17712 In both cases, agetty will leave the other serial device settings
17713 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
17716 @item @code{baud-rate} (default: @code{#f})
17717 A string containing a comma-separated list of one or more baud rates, in
17720 @item @code{term} (default: @code{#f})
17721 A string containing the value used for the @env{TERM} environment
17724 @item @code{eight-bits?} (default: @code{#f})
17725 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
17728 @item @code{auto-login} (default: @code{#f})
17729 When passed a login name, as a string, the specified user will be logged
17730 in automatically without prompting for their login name or password.
17732 @item @code{no-reset?} (default: @code{#f})
17733 When @code{#t}, don't reset terminal cflags (control modes).
17735 @item @code{host} (default: @code{#f})
17736 This accepts a string containing the ``login_host'', which will be written
17737 into the @file{/var/run/utmpx} file.
17739 @item @code{remote?} (default: @code{#f})
17740 When set to @code{#t} in conjunction with @var{host}, this will add an
17741 @code{-r} fakehost option to the command line of the login program
17742 specified in @var{login-program}.
17744 @item @code{flow-control?} (default: @code{#f})
17745 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
17747 @item @code{no-issue?} (default: @code{#f})
17748 When set to @code{#t}, the contents of the @file{/etc/issue} file will
17749 not be displayed before presenting the login prompt.
17751 @item @code{init-string} (default: @code{#f})
17752 This accepts a string that will be sent to the tty or modem before
17753 sending anything else. It can be used to initialize a modem.
17755 @item @code{no-clear?} (default: @code{#f})
17756 When set to @code{#t}, agetty will not clear the screen before showing
17759 @item @code{login-program} (default: (file-append shadow "/bin/login"))
17760 This must be either a gexp denoting the name of a log-in program, or
17761 unset, in which case the default value is the @command{login} from the
17764 @item @code{local-line} (default: @code{#f})
17765 Control the CLOCAL line flag. This accepts one of three symbols as
17766 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
17767 the default value chosen by agetty is @code{'auto}.
17769 @item @code{extract-baud?} (default: @code{#f})
17770 When set to @code{#t}, instruct agetty to try to extract the baud rate
17771 from the status messages produced by certain types of modems.
17773 @item @code{skip-login?} (default: @code{#f})
17774 When set to @code{#t}, do not prompt the user for a login name. This
17775 can be used with @var{login-program} field to use non-standard login
17778 @item @code{no-newline?} (default: @code{#f})
17779 When set to @code{#t}, do not print a newline before printing the
17780 @file{/etc/issue} file.
17782 @c Is this dangerous only when used with login-program, or always?
17783 @item @code{login-options} (default: @code{#f})
17784 This option accepts a string containing options that are passed to the
17785 login program. When used with the @var{login-program}, be aware that a
17786 malicious user could try to enter a login name containing embedded
17787 options that could be parsed by the login program.
17789 @item @code{login-pause} (default: @code{#f})
17790 When set to @code{#t}, wait for any key before showing the login prompt.
17791 This can be used in conjunction with @var{auto-login} to save memory by
17792 lazily spawning shells.
17794 @item @code{chroot} (default: @code{#f})
17795 Change root to the specified directory. This option accepts a directory
17798 @item @code{hangup?} (default: @code{#f})
17799 Use the Linux system call @code{vhangup} to do a virtual hangup of the
17800 specified terminal.
17802 @item @code{keep-baud?} (default: @code{#f})
17803 When set to @code{#t}, try to keep the existing baud rate. The baud
17804 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
17807 @item @code{timeout} (default: @code{#f})
17808 When set to an integer value, terminate if no user name could be read
17809 within @var{timeout} seconds.
17811 @item @code{detect-case?} (default: @code{#f})
17812 When set to @code{#t}, turn on support for detecting an uppercase-only
17813 terminal. This setting will detect a login name containing only
17814 uppercase letters as indicating an uppercase-only terminal and turn on
17815 some upper-to-lower case conversions. Note that this will not support
17816 Unicode characters.
17818 @item @code{wait-cr?} (default: @code{#f})
17819 When set to @code{#t}, wait for the user or modem to send a
17820 carriage-return or linefeed character before displaying
17821 @file{/etc/issue} or login prompt. This is typically used with the
17822 @var{init-string} option.
17824 @item @code{no-hints?} (default: @code{#f})
17825 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
17828 @item @code{no-hostname?} (default: @code{#f})
17829 By default, the hostname is printed. When this option is set to
17830 @code{#t}, no hostname will be shown at all.
17832 @item @code{long-hostname?} (default: @code{#f})
17833 By default, the hostname is only printed until the first dot. When this
17834 option is set to @code{#t}, the fully qualified hostname by
17835 @code{gethostname} or @code{getaddrinfo} is shown.
17837 @item @code{erase-characters} (default: @code{#f})
17838 This option accepts a string of additional characters that should be
17839 interpreted as backspace when the user types their login name.
17841 @item @code{kill-characters} (default: @code{#f})
17842 This option accepts a string that should be interpreted to mean ``ignore
17843 all previous characters'' (also called a ``kill'' character) when the user
17844 types their login name.
17846 @item @code{chdir} (default: @code{#f})
17847 This option accepts, as a string, a directory path that will be changed
17850 @item @code{delay} (default: @code{#f})
17851 This options accepts, as an integer, the number of seconds to sleep
17852 before opening the tty and displaying the login prompt.
17854 @item @code{nice} (default: @code{#f})
17855 This option accepts, as an integer, the nice value with which to run the
17856 @command{login} program.
17858 @item @code{extra-options} (default: @code{'()})
17859 This option provides an ``escape hatch'' for the user to provide arbitrary
17860 command-line arguments to @command{agetty} as a list of strings.
17862 @item @code{shepherd-requirement} (default: @code{'()})
17863 The option can be used to provides extra shepherd requirements (for example
17864 @code{'syslogd}) to the respective @code{'term-}* shepherd service.
17869 @deffn {Scheme Procedure} kmscon-service-type @var{config}
17870 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
17871 according to @var{config}, a @code{<kmscon-configuration>} object, which
17872 specifies the tty to run, among other things.
17875 @deftp {Data Type} kmscon-configuration
17876 This is the data type representing the configuration of Kmscon, which
17877 implements virtual console log-in.
17881 @item @code{virtual-terminal}
17882 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
17884 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
17885 A gexp denoting the name of the log-in program. The default log-in program is
17886 @command{login} from the Shadow tool suite.
17888 @item @code{login-arguments} (default: @code{'("-p")})
17889 A list of arguments to pass to @command{login}.
17891 @item @code{auto-login} (default: @code{#f})
17892 When passed a login name, as a string, the specified user will be logged
17893 in automatically without prompting for their login name or password.
17895 @item @code{hardware-acceleration?} (default: #f)
17896 Whether to use hardware acceleration.
17898 @item @code{font-engine} (default: @code{"pango"})
17899 Font engine used in Kmscon.
17901 @item @code{font-size} (default: @code{12})
17902 Font size used in Kmscon.
17904 @item @code{keyboard-layout} (default: @code{#f})
17905 If this is @code{#f}, Kmscon uses the default keyboard layout---usually US
17906 English (``qwerty'') for a 105-key PC keyboard.
17908 Otherwise this must be a @code{keyboard-layout} object specifying the
17909 keyboard layout. @xref{Keyboard Layout}, for more information on how to
17910 specify the keyboard layout.
17912 @item @code{kmscon} (default: @var{kmscon})
17913 The Kmscon package to use.
17918 @cindex name service cache daemon
17920 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
17921 [#:name-services '()]
17922 Return a service that runs the libc name service cache daemon (nscd) with the
17923 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
17924 Service Switch}, for an example.
17926 For convenience, the Shepherd service for nscd provides the following actions:
17930 @cindex cache invalidation, nscd
17931 @cindex nscd, cache invalidation
17932 This invalidate the given cache. For instance, running:
17935 herd invalidate nscd hosts
17939 invalidates the host name lookup cache of nscd.
17942 Running @command{herd statistics nscd} displays information about nscd usage
17948 @defvr {Scheme Variable} %nscd-default-configuration
17949 This is the default @code{<nscd-configuration>} value (see below) used
17950 by @code{nscd-service}. It uses the caches defined by
17951 @code{%nscd-default-caches}; see below.
17954 @deftp {Data Type} nscd-configuration
17955 This is the data type representing the name service cache daemon (nscd)
17960 @item @code{name-services} (default: @code{'()})
17961 List of packages denoting @dfn{name services} that must be visible to
17962 the nscd---e.g., @code{(list @var{nss-mdns})}.
17964 @item @code{glibc} (default: @var{glibc})
17965 Package object denoting the GNU C Library providing the @command{nscd}
17968 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
17969 Name of the nscd log file. This is where debugging output goes when
17970 @code{debug-level} is strictly positive.
17972 @item @code{debug-level} (default: @code{0})
17973 Integer denoting the debugging levels. Higher numbers mean that more
17974 debugging output is logged.
17976 @item @code{caches} (default: @code{%nscd-default-caches})
17977 List of @code{<nscd-cache>} objects denoting things to be cached; see
17983 @deftp {Data Type} nscd-cache
17984 Data type representing a cache database of nscd and its parameters.
17988 @item @code{database}
17989 This is a symbol representing the name of the database to be cached.
17990 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
17991 @code{services}, which designate the corresponding NSS database
17992 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
17994 @item @code{positive-time-to-live}
17995 @itemx @code{negative-time-to-live} (default: @code{20})
17996 A number representing the number of seconds during which a positive or
17997 negative lookup result remains in cache.
17999 @item @code{check-files?} (default: @code{#t})
18000 Whether to check for updates of the files corresponding to
18003 For instance, when @var{database} is @code{hosts}, setting this flag
18004 instructs nscd to check for updates in @file{/etc/hosts} and to take
18007 @item @code{persistent?} (default: @code{#t})
18008 Whether the cache should be stored persistently on disk.
18010 @item @code{shared?} (default: @code{#t})
18011 Whether the cache should be shared among users.
18013 @item @code{max-database-size} (default: 32@tie{}MiB)
18014 Maximum size in bytes of the database cache.
18016 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
18017 @c settings, so leave them out.
18022 @defvr {Scheme Variable} %nscd-default-caches
18023 List of @code{<nscd-cache>} objects used by default by
18024 @code{nscd-configuration} (see above).
18026 It enables persistent and aggressive caching of service and host name
18027 lookups. The latter provides better host name lookup performance,
18028 resilience in the face of unreliable name servers, and also better
18029 privacy---often the result of host name lookups is in local cache, so
18030 external name servers do not even need to be queried.
18033 @anchor{syslog-configuration-type}
18036 @deftp {Data Type} syslog-configuration
18037 This data type represents the configuration of the syslog daemon.
18040 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
18041 The syslog daemon to use.
18043 @item @code{config-file} (default: @code{%default-syslog.conf})
18044 The syslog configuration file to use.
18049 @anchor{syslog-service}
18051 @deffn {Scheme Procedure} syslog-service @var{config}
18052 Return a service that runs a syslog daemon according to @var{config}.
18054 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
18055 information on the configuration file syntax.
18058 @defvr {Scheme Variable} guix-service-type
18059 This is the type of the service that runs the build daemon,
18060 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
18061 @code{guix-configuration} record as described below.
18064 @anchor{guix-configuration-type}
18065 @deftp {Data Type} guix-configuration
18066 This data type represents the configuration of the Guix build daemon.
18067 @xref{Invoking guix-daemon}, for more information.
18070 @item @code{guix} (default: @var{guix})
18071 The Guix package to use.
18073 @item @code{build-group} (default: @code{"guixbuild"})
18074 Name of the group for build user accounts.
18076 @item @code{build-accounts} (default: @code{10})
18077 Number of build user accounts to create.
18079 @item @code{authorize-key?} (default: @code{#t})
18080 @cindex substitutes, authorization thereof
18081 Whether to authorize the substitute keys listed in
18082 @code{authorized-keys}---by default that of
18083 @code{@value{SUBSTITUTE-SERVER-1}} and
18084 @code{@value{SUBSTITUTE-SERVER-2}}
18085 (@pxref{Substitutes}).
18087 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
18088 changed by invoking @command{guix archive --authorize}. You must
18089 instead adjust @code{guix-configuration} as you wish and reconfigure the
18090 system. This ensures that your operating system configuration file is
18094 When booting or reconfiguring to a system where @code{authorize-key?}
18095 is true, the existing @file{/etc/guix/acl} file is backed up as
18096 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
18097 file. This is to facilitate migration from earlier versions, which
18098 allowed for in-place modifications to @file{/etc/guix/acl}.
18101 @vindex %default-authorized-guix-keys
18102 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
18103 The list of authorized key files for archive imports, as a list of
18104 string-valued gexps (@pxref{Invoking guix archive}). By default, it
18105 contains that of @code{@value{SUBSTITUTE-SERVER-1}} and
18106 @code{@value{SUBSTITUTE-SERVER-2}} (@pxref{Substitutes}). See
18107 @code{substitute-urls} below for an example on how to change it.
18109 @item @code{use-substitutes?} (default: @code{#t})
18110 Whether to use substitutes.
18112 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
18113 The list of URLs where to look for substitutes by default.
18115 Suppose you would like to fetch substitutes from @code{guix.example.org}
18116 in addition to @code{@value{SUBSTITUTE-SERVER-1}}. You will need to do
18117 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
18118 and (2) authorize its signing key, having done appropriate checks
18119 (@pxref{Substitute Server Authorization}). The configuration below does
18123 (guix-configuration
18125 (append (list "https://guix.example.org")
18126 %default-substitute-urls))
18128 (append (list (local-file "./guix.example.org-key.pub"))
18129 %default-authorized-guix-keys)))
18132 This example assumes that the file @file{./guix.example.org-key.pub}
18133 contains the public key that @code{guix.example.org} uses to sign
18136 @item @code{generate-substitute-key?} (default: @code{#t})
18137 Whether to generate a @dfn{substitute key pair} under
18138 @file{/etc/guix/signing-key.pub} and @file{/etc/guix/signing-key.sec} if
18139 there is not already one.
18141 This key pair is used when exporting store items, for instance with
18142 @command{guix publish} (@pxref{Invoking guix publish}) or @command{guix
18143 archive} (@pxref{Invoking guix archive}). Generating a key pair takes a
18144 few seconds when enough entropy is available and is only done once; you
18145 might want to turn it off for instance in a virtual machine that does
18146 not need it and where the extra boot time is a problem.
18148 @item @code{max-silent-time} (default: @code{0})
18149 @itemx @code{timeout} (default: @code{0})
18150 The number of seconds of silence and the number of seconds of activity,
18151 respectively, after which a build process times out. A value of zero
18152 disables the timeout.
18154 @item @code{log-compression} (default: @code{'gzip})
18155 The type of compression used for build logs---one of @code{gzip},
18156 @code{bzip2}, or @code{none}.
18158 @item @code{discover?} (default: @code{#f})
18159 Whether to discover substitute servers on the local network using mDNS
18162 @item @code{extra-options} (default: @code{'()})
18163 List of extra command-line options for @command{guix-daemon}.
18165 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
18166 File where @command{guix-daemon}'s standard output and standard error
18169 @cindex HTTP proxy, for @code{guix-daemon}
18170 @cindex proxy, for @code{guix-daemon} HTTP access
18171 @item @code{http-proxy} (default: @code{#f})
18172 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
18173 derivations and substitutes.
18175 It is also possible to change the daemon's proxy at run time through the
18176 @code{set-http-proxy} action, which restarts it:
18179 herd set-http-proxy guix-daemon http://localhost:8118
18182 To clear the proxy settings, run:
18185 herd set-http-proxy guix-daemon
18188 @item @code{tmpdir} (default: @code{#f})
18189 A directory path where the @command{guix-daemon} will perform builds.
18194 @deftp {Data Type} guix-extension
18196 This data type represents the parameters of the Guix build daemon that
18197 are extendable. This is the type of the object that must be used within
18198 a guix service extension.
18199 @xref{Service Composition}, for more information.
18202 @item @code{authorized-keys} (default: @code{'()})
18203 A list of file-like objects where each element contains a public key.
18205 @item @code{substitute-urls} (default: @code{'()})
18206 A list of strings where each element is a substitute URL.
18208 @item @code{chroot-directories} (default: @code{'()})
18209 A list of file-like objects or strings pointing to additional directories the build daemon can use.
18213 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
18214 Run @var{udev}, which populates the @file{/dev} directory dynamically.
18215 udev rules can be provided as a list of files through the @var{rules}
18216 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
18217 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
18218 creation of such rule files.
18220 The @command{herd rules udev} command, as root, returns the name of the
18221 directory containing all the active udev rules.
18224 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
18225 Return a udev-rule file named @var{file-name} containing the rules
18226 defined by the @var{contents} literal.
18228 In the following example, a rule for a USB device is defined to be
18229 stored in the file @file{90-usb-thing.rules}. The rule runs a script
18230 upon detecting a USB device with a given product identifier.
18233 (define %example-udev-rule
18235 "90-usb-thing.rules"
18236 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
18237 "ATTR@{product@}==\"Example\", "
18238 "RUN+=\"/path/to/script\"")))
18242 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
18243 [#:groups @var{groups}]
18244 Return a service that extends @code{udev-service-type } with @var{rules}
18245 and @code{account-service-type} with @var{groups} as system groups.
18246 This works by creating a singleton service type
18247 @code{@var{name}-udev-rules}, of which the returned service is an
18250 Here we show how it can be used to extend @code{udev-service-type} with the
18251 previously defined rule @code{%example-udev-rule}.
18257 (cons (udev-rules-service 'usb-thing %example-udev-rule)
18258 %desktop-services)))
18262 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
18263 Return a udev file named @var{file-name} containing the rules defined
18264 within @var{file}, a file-like object.
18266 The following example showcases how we can use an existing rule file.
18269 (use-modules (guix download) ;for url-fetch
18270 (guix packages) ;for origin
18273 (define %android-udev-rules
18275 "51-android-udev.rules"
18276 (let ((version "20170910"))
18279 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
18280 "android-udev-rules/" version "/51-android.rules"))
18282 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
18286 Additionally, Guix package definitions can be included in @var{rules} in
18287 order to extend the udev rules with the definitions found under their
18288 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
18289 @var{file->udev-rule} example, we could have used the
18290 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
18291 packages android)} module.
18293 The following example shows how to use the @var{android-udev-rules}
18294 package so that the Android tool @command{adb} can detect devices
18295 without root privileges. It also details how to create the
18296 @code{adbusers} group, which is required for the proper functioning of
18297 the rules defined within the @code{android-udev-rules} package. To
18298 create such a group, we must define it both as part of the
18299 @code{supplementary-groups} of our @code{user-account} declaration, as
18300 well as in the @var{groups} of the @code{udev-rules-service} procedure.
18303 (use-modules (gnu packages android) ;for android-udev-rules
18304 (gnu system shadow) ;for user-group
18309 (users (cons (user-account
18311 (supplementary-groups
18312 '("adbusers" ;for adb
18313 "wheel" "netdev" "audio" "video")))))
18316 (cons (udev-rules-service 'android android-udev-rules
18317 #:groups '("adbusers"))
18318 %desktop-services)))
18321 @defvr {Scheme Variable} urandom-seed-service-type
18322 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
18323 when rebooting. It also tries to seed @file{/dev/urandom} from
18324 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
18328 @defvr {Scheme Variable} %random-seed-file
18329 This is the name of the file where some random bytes are saved by
18330 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
18331 It defaults to @file{/var/lib/random-seed}.
18336 @defvr {Scheme Variable} gpm-service-type
18337 This is the type of the service that runs GPM, the @dfn{general-purpose
18338 mouse daemon}, which provides mouse support to the Linux console. GPM
18339 allows users to use the mouse in the console, notably to select, copy,
18342 The value for services of this type must be a @code{gpm-configuration}
18343 (see below). This service is not part of @code{%base-services}.
18346 @deftp {Data Type} gpm-configuration
18347 Data type representing the configuration of GPM.
18350 @item @code{options} (default: @code{%default-gpm-options})
18351 Command-line options passed to @command{gpm}. The default set of
18352 options instruct @command{gpm} to listen to mouse events on
18353 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
18356 @item @code{gpm} (default: @code{gpm})
18357 The GPM package to use.
18362 @anchor{guix-publish-service-type}
18363 @deffn {Scheme Variable} guix-publish-service-type
18364 This is the service type for @command{guix publish} (@pxref{Invoking
18365 guix publish}). Its value must be a @code{guix-publish-configuration}
18366 object, as described below.
18368 This assumes that @file{/etc/guix} already contains a signing key pair as
18369 created by @command{guix archive --generate-key} (@pxref{Invoking guix
18370 archive}). If that is not the case, the service will fail to start.
18373 @deftp {Data Type} guix-publish-configuration
18374 Data type representing the configuration of the @code{guix publish}
18378 @item @code{guix} (default: @code{guix})
18379 The Guix package to use.
18381 @item @code{port} (default: @code{80})
18382 The TCP port to listen for connections.
18384 @item @code{host} (default: @code{"localhost"})
18385 The host (and thus, network interface) to listen to. Use
18386 @code{"0.0.0.0"} to listen on all the network interfaces.
18388 @item @code{advertise?} (default: @code{#f})
18389 When true, advertise the service on the local network @i{via} the DNS-SD
18390 protocol, using Avahi.
18392 This allows neighboring Guix devices with discovery on (see
18393 @code{guix-configuration} above) to discover this @command{guix publish}
18394 instance and to automatically download substitutes from it.
18396 @item @code{compression} (default: @code{'(("gzip" 3) ("zstd" 3))})
18397 This is a list of compression method/level tuple used when compressing
18398 substitutes. For example, to compress all substitutes with @emph{both} lzip
18399 at level 7 and gzip at level 9, write:
18402 '(("lzip" 7) ("gzip" 9))
18405 Level 9 achieves the best compression ratio at the expense of increased CPU
18406 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
18407 publish}, for more information on the available compression methods and
18408 the tradeoffs involved.
18410 An empty list disables compression altogether.
18412 @item @code{nar-path} (default: @code{"nar"})
18413 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
18414 publish, @option{--nar-path}}, for details.
18416 @item @code{cache} (default: @code{#f})
18417 When it is @code{#f}, disable caching and instead generate archives on
18418 demand. Otherwise, this should be the name of a directory---e.g.,
18419 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
18420 archives and meta-data ready to be sent. @xref{Invoking guix publish,
18421 @option{--cache}}, for more information on the tradeoffs involved.
18423 @item @code{workers} (default: @code{#f})
18424 When it is an integer, this is the number of worker threads used for
18425 caching; when @code{#f}, the number of processors is used.
18426 @xref{Invoking guix publish, @option{--workers}}, for more information.
18428 @item @code{cache-bypass-threshold} (default: 10 MiB)
18429 When @code{cache} is true, this is the maximum size in bytes of a store
18430 item for which @command{guix publish} may bypass its cache in case of a
18431 cache miss. @xref{Invoking guix publish,
18432 @option{--cache-bypass-threshold}}, for more information.
18434 @item @code{ttl} (default: @code{#f})
18435 When it is an integer, this denotes the @dfn{time-to-live} in seconds
18436 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
18437 for more information.
18439 @item @code{negative-ttl} (default: @code{#f})
18440 When it is an integer, this denotes the @dfn{time-to-live} in
18441 seconds for the negative lookups. @xref{Invoking guix publish,
18442 @option{--negative-ttl}}, for more information.
18446 @anchor{rngd-service}
18447 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
18448 [#:device "/dev/hwrng"]
18449 Return a service that runs the @command{rngd} program from @var{rng-tools}
18450 to add @var{device} to the kernel's entropy pool. The service will fail if
18451 @var{device} does not exist.
18454 @anchor{pam-limits-service}
18455 @cindex session limits
18461 @cindex open file descriptors
18462 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
18464 Return a service that installs a configuration file for the
18465 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
18466 @code{pam_limits} module}. The procedure optionally takes a list of
18467 @code{pam-limits-entry} values, which can be used to specify
18468 @code{ulimit} limits and @code{nice} priority limits to user sessions.
18470 The following limits definition sets two hard and soft limits for all
18471 login sessions of users in the @code{realtime} group:
18474 (pam-limits-service
18476 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
18477 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
18480 The first entry increases the maximum realtime priority for
18481 non-privileged processes; the second entry lifts any restriction of the
18482 maximum address space that can be locked in memory. These settings are
18483 commonly used for real-time audio systems.
18485 Another useful example is raising the maximum number of open file
18486 descriptors that can be used:
18489 (pam-limits-service
18491 (pam-limits-entry "*" 'both 'nofile 100000)))
18494 In the above example, the asterisk means the limit should apply to any
18495 user. It is important to ensure the chosen value doesn't exceed the
18496 maximum system value visible in the @file{/proc/sys/fs/file-max} file,
18497 else the users would be prevented from login in. For more information
18498 about the Pluggable Authentication Module (PAM) limits, refer to the
18499 @samp{pam_limits} man page from the @code{linux-pam} package.
18502 @defvr {Scheme Variable} greetd-service-type
18503 @uref{https://git.sr.ht/~kennylevinsen/greetd, @code{greetd}} is a minimal and
18504 flexible login manager daemon, that makes no assumptions about what you
18507 If you can run it from your shell in a TTY, greetd can start it. If it
18508 can be taught to speak a simple JSON-based IPC protocol, then it can be
18511 @code{greetd-service-type} provides necessary infrastructure for logging
18512 in users, including:
18516 @code{greetd} PAM service
18519 Special variation of @code{pam-mount} to mount @code{XDG_RUNTIME_DIR}
18522 Here is example of switching from @code{mingetty-service-type} to
18523 @code{greetd-service-type}, and how different terminals could be:
18527 (modify-services %base-services
18528 ;; greetd-service-type provides "greetd" PAM service
18529 (delete login-service-type)
18530 ;; and can be used in place of mingetty-service-type
18531 (delete mingetty-service-type))
18533 (service greetd-service-type
18534 (greetd-configuration
18537 ;; we can make any terminal active by default
18538 (greetd-terminal-configuration (terminal-vt "1") (terminal-switch #t))
18539 ;; we can make environment without XDG_RUNTIME_DIR set
18540 ;; even provide our own environment variables
18541 (greetd-terminal-configuration
18543 (default-session-command
18544 (greetd-agreety-session
18545 (extra-env '(("MY_VAR" . "1")))
18547 ;; we can use different shell instead of default bash
18548 (greetd-terminal-configuration
18550 (default-session-command
18551 (greetd-agreety-session (command (file-append zsh "/bin/zsh")))))
18552 ;; we can use any other executable command as greeter
18553 (greetd-terminal-configuration
18555 (default-session-command (program-file "my-noop-greeter" #~(exit))))
18556 (greetd-terminal-configuration (terminal-vt "5"))
18557 (greetd-terminal-configuration (terminal-vt "6"))))))
18558 ;; mingetty-service-type can be used in parallel
18559 ;; if needed to do so, do not (delete login-service-type)
18560 ;; as illustrated above
18561 #| (service mingetty-service-type (mingetty-configuration (tty "tty8"))) |#))
18565 @deftp {Data Type} greetd-configuration
18566 Configuration record for the @code{greetd-service-type}.
18570 A file-like object containing the ``message of the day''.
18572 @item @code{allow-empty-passwords?} (default: @code{#t})
18573 Allow empty passwords by default so that first-time users can log in when
18574 the 'root' account has just been created.
18576 @item @code{terminals} (default: @code{'()})
18577 List of @code{greetd-terminal-configuration} per terminal for which
18578 @code{greetd} should be started.
18580 @item @code{greeter-supplementary-groups} (default: @code{'()})
18581 List of groups which should be added to @code{greeter} user. For instance:
18583 (greeter-supplementary-groups '("seat" "video"))
18585 Note that this example will fail if @code{seat} group does not exist.
18589 @deftp {Data Type} greetd-terminal-configuration
18590 Configuration record for per terminal greetd daemon service.
18593 @item @code{greetd} (default: @code{greetd})
18594 The greetd package to use.
18596 @item @code{config-file-name}
18597 Configuration file name to use for greetd daemon. Generally, autogenerated
18598 derivation based on @code{terminal-vt} value.
18600 @item @code{log-file-name}
18601 Log file name to use for greetd daemon. Generally, autogenerated
18602 name based on @code{terminal-vt} value.
18604 @item @code{terminal-vt} (default: @samp{"7"})
18605 The VT to run on. Use of a specific VT with appropriate conflict avoidance
18608 @item @code{terminal-switch} (default: @code{#f})
18609 Make this terminal active on start of @code{greetd}.
18611 @item @code{default-session-user} (default: @samp{"greeter"})
18612 The user to use for running the greeter.
18614 @item @code{default-session-command} (default: @code{(greetd-agreety-session)})
18615 Can be either instance of @code{greetd-agreety-session} configuration or
18616 @code{gexp->script} like object to use as greeter.
18621 @deftp {Data Type} greetd-agreety-session
18622 Configuration record for the agreety greetd greeter.
18625 @item @code{agreety} (default: @code{greetd})
18626 The package with @command{/bin/agreety} command.
18628 @item @code{command} (default: @code{(file-append bash "/bin/bash")})
18629 Command to be started by @command{/bin/agreety} on successful login.
18631 @item @code{command-args} (default: @code{'("-l")})
18632 Command arguments to pass to command.
18634 @item @code{extra-env} (default: @code{'()})
18635 Extra environment variables to set on login.
18637 @item @code{xdg-env?} (default: @code{#t})
18638 If true @code{XDG_RUNTIME_DIR} and @code{XDG_SESSION_TYPE} will be set
18639 before starting command. One should note that, @code{extra-env} variables
18640 are set right after mentioned variables, so that they can be overriden.
18645 @node Scheduled Job Execution
18646 @subsection Scheduled Job Execution
18650 @cindex scheduling jobs
18651 The @code{(gnu services mcron)} module provides an interface to
18652 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
18653 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
18654 Unix @command{cron} daemon; the main difference is that it is
18655 implemented in Guile Scheme, which provides a lot of flexibility when
18656 specifying the scheduling of jobs and their actions.
18658 The example below defines an operating system that runs the
18659 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
18660 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
18661 well as the @command{mkid} command on behalf of an unprivileged user
18662 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
18663 gexps to introduce job definitions that are passed to mcron
18664 (@pxref{G-Expressions}).
18667 (use-modules (guix) (gnu) (gnu services mcron))
18668 (use-package-modules base idutils)
18670 (define updatedb-job
18671 ;; Run 'updatedb' at 3AM every day. Here we write the
18672 ;; job's action as a Scheme procedure.
18673 #~(job '(next-hour '(3))
18675 (execl (string-append #$findutils "/bin/updatedb")
18677 "--prunepaths=/tmp /var/tmp /gnu/store"))
18680 (define garbage-collector-job
18681 ;; Collect garbage 5 minutes after midnight every day.
18682 ;; The job's action is a shell command.
18683 #~(job "5 0 * * *" ;Vixie cron syntax
18686 (define idutils-job
18687 ;; Update the index database as user "charlie" at 12:15PM
18688 ;; and 19:15PM. This runs from the user's home directory.
18689 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
18690 (string-append #$idutils "/bin/mkid src")
18696 ;; %BASE-SERVICES already includes an instance of
18697 ;; 'mcron-service-type', which we extend with additional
18698 ;; jobs using 'simple-service'.
18699 (services (cons (simple-service 'my-cron-jobs
18701 (list garbage-collector-job
18708 When providing the action of a job specification as a procedure, you
18709 should provide an explicit name for the job via the optional 3rd
18710 argument as done in the @code{updatedb-job} example above. Otherwise,
18711 the job would appear as ``Lambda function'' in the output of
18712 @command{herd schedule mcron}, which is not nearly descriptive enough!
18715 For more complex jobs defined in Scheme where you need control over the top
18716 level, for instance to introduce a @code{use-modules} form, you can move your
18717 code to a separate program using the @code{program-file} procedure of the
18718 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
18722 (define %battery-alert-job
18723 ;; Beep when the battery percentage falls below %MIN-LEVEL.
18725 '(next-minute (range 0 60 1))
18727 "battery-alert.scm"
18728 (with-imported-modules (source-module-closure
18729 '((guix build utils)))
18731 (use-modules (guix build utils)
18734 (ice-9 textual-ports)
18737 (define %min-level 20)
18739 (setenv "LC_ALL" "C") ;ensure English output
18740 (and-let* ((input-pipe (open-pipe*
18742 #$(file-append acpi "/bin/acpi")))
18743 (output (get-string-all input-pipe))
18744 (m (string-match "Discharging, ([0-9]+)%" output))
18745 (level (string->number (match:substring m 1)))
18746 ((< level %min-level)))
18747 (format #t "warning: Battery level is low (~a%)~%" level)
18748 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
18751 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
18752 for more information on mcron job specifications. Below is the
18753 reference of the mcron service.
18755 On a running system, you can use the @code{schedule} action of the service to
18756 visualize the mcron jobs that will be executed next:
18759 # herd schedule mcron
18763 The example above lists the next five tasks that will be executed, but you can
18764 also specify the number of tasks to display:
18767 # herd schedule mcron 10
18770 @defvr {Scheme Variable} mcron-service-type
18771 This is the type of the @code{mcron} service, whose value is an
18772 @code{mcron-configuration} object.
18774 This service type can be the target of a service extension that provides
18775 additional job specifications (@pxref{Service Composition}). In other
18776 words, it is possible to define services that provide additional mcron
18780 @deftp {Data Type} mcron-configuration
18781 Data type representing the configuration of mcron.
18784 @item @code{mcron} (default: @var{mcron})
18785 The mcron package to use.
18788 This is a list of gexps (@pxref{G-Expressions}), where each gexp
18789 corresponds to an mcron job specification (@pxref{Syntax, mcron job
18790 specifications,, mcron, GNU@tie{}mcron}).
18796 @subsection Log Rotation
18799 @cindex log rotation
18801 Log files such as those found in @file{/var/log} tend to grow endlessly,
18802 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
18803 their contents in separate files, possibly compressed. The @code{(gnu
18804 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
18805 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
18807 This service is part of @code{%base-services}, and thus enabled by
18808 default, with the default settings, for commonly encountered log files.
18809 The example below shows how to extend it with an additional
18810 @dfn{rotation}, should you need to do that (usually, services that
18811 produce log files already take care of that):
18814 (use-modules (guix) (gnu))
18815 (use-service-modules admin)
18817 (define my-log-files
18818 ;; Log files that I want to rotate.
18819 '("/var/log/something.log" "/var/log/another.log"))
18823 (services (cons (simple-service 'rotate-my-stuff
18824 rottlog-service-type
18825 (list (log-rotation
18827 (files my-log-files))))
18831 @defvr {Scheme Variable} rottlog-service-type
18832 This is the type of the Rottlog service, whose value is a
18833 @code{rottlog-configuration} object.
18835 Other services can extend this one with new @code{log-rotation} objects
18836 (see below), thereby augmenting the set of files to be rotated.
18838 This service type can define mcron jobs (@pxref{Scheduled Job
18839 Execution}) to run the rottlog service.
18842 @deftp {Data Type} rottlog-configuration
18843 Data type representing the configuration of rottlog.
18846 @item @code{rottlog} (default: @code{rottlog})
18847 The Rottlog package to use.
18849 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
18850 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
18851 rottlog, GNU Rot[t]log Manual}).
18853 @item @code{rotations} (default: @code{%default-rotations})
18854 A list of @code{log-rotation} objects as defined below.
18857 This is a list of gexps where each gexp corresponds to an mcron job
18858 specification (@pxref{Scheduled Job Execution}).
18862 @deftp {Data Type} log-rotation
18863 Data type representing the rotation of a group of log files.
18865 Taking an example from the Rottlog manual (@pxref{Period Related File
18866 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
18872 (files '("/var/log/apache/*"))
18873 (options '("storedir apache-archives"
18879 The list of fields is as follows:
18882 @item @code{frequency} (default: @code{'weekly})
18883 The log rotation frequency, a symbol.
18886 The list of files or file glob patterns to rotate.
18888 @vindex %default-log-rotation-options
18889 @item @code{options} (default: @code{%default-log-rotation-options})
18890 The list of rottlog options for this rotation (@pxref{Configuration
18891 parameters,,, rottlog, GNU Rot[t]log Manual}).
18893 @item @code{post-rotate} (default: @code{#f})
18894 Either @code{#f} or a gexp to execute once the rotation has completed.
18898 @defvr {Scheme Variable} %default-rotations
18899 Specifies weekly rotation of @code{%rotated-files} and of
18900 @file{/var/log/guix-daemon.log}.
18903 @defvr {Scheme Variable} %rotated-files
18904 The list of syslog-controlled files to be rotated. By default it is:
18905 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
18906 "/var/log/maillog")}.
18909 Some log files just need to be deleted periodically once they are old,
18910 without any other criterion and without any archival step. This is the
18911 case of build logs stored by @command{guix-daemon} under
18912 @file{/var/log/guix/drvs} (@pxref{Invoking guix-daemon}). The
18913 @code{log-cleanup} service addresses this use case. For example,
18914 @code{%base-services} (@pxref{Base Services}) includes the following:
18917 ;; Periodically delete old build logs.
18918 (service log-cleanup-service-type
18919 (log-cleanup-configuration
18920 (directory "/var/log/guix/drvs")))
18923 That ensures build logs do not accumulate endlessly.
18925 @defvr {Scheme Variable} log-cleanup-service-type
18926 This is the type of the service to delete old logs. Its value must be a
18927 @code{log-cleanup-configuration} record as described below.
18930 @deftp {Data Type} log-cleanup-configuration
18931 Data type representing the log cleanup configuration
18934 @item @code{directory}
18935 Name of the directory containing log files.
18937 @item @code{expiry} (default: @code{(* 6 30 24 3600)})
18938 Age in seconds after which a file is subject to deletion (six months by
18941 @item @code{schedule} (default: @code{"30 12 01,08,15,22 * *"})
18942 String or gexp denoting the corresponding mcron job schedule
18943 (@pxref{Scheduled Job Execution}).
18947 @cindex logging, anonymization
18948 @subheading Anonip Service
18950 Anonip is a privacy filter that removes IP address from web server logs.
18951 This service creates a FIFO and filters any written lines with anonip
18952 before writing the filtered log to a target file.
18954 The following example sets up the FIFO
18955 @file{/var/run/anonip/https.access.log} and writes the filtered log file
18956 @file{/var/log/anonip/https.access.log}.
18959 (service anonip-service-type
18960 (anonip-configuration
18961 (input "/var/run/anonip/https.access.log")
18962 (output "/var/log/anonip/https.access.log")))
18965 Configure your web server to write its logs to the FIFO at
18966 @file{/var/run/anonip/https.access.log} and collect the anonymized log
18967 file at @file{/var/web-logs/https.access.log}.
18969 @deftp {Data Type} anonip-configuration
18970 This data type represents the configuration of anonip.
18971 It has the following parameters:
18974 @item @code{anonip} (default: @code{anonip})
18975 The anonip package to use.
18978 The file name of the input log file to process. The service creates a
18979 FIFO of this name. The web server should write its logs to this FIFO.
18981 @item @code{output}
18982 The file name of the processed log file.
18985 The following optional settings may be provided:
18988 @item @code{skip-private?}
18989 When @code{#true} do not mask addresses in private ranges.
18991 @item @code{column}
18992 A 1-based indexed column number. Assume IP address is in the specified
18993 column (default is 1).
18995 @item @code{replacement}
18996 Replacement string in case address parsing fails, e.g. @code{"0.0.0.0"}.
18998 @item @code{ipv4mask}
18999 Number of bits to mask in IPv4 addresses.
19001 @item @code{ipv6mask}
19002 Number of bits to mask in IPv6 addresses.
19004 @item @code{increment}
19005 Increment the IP address by the given number. By default this is zero.
19007 @item @code{delimiter}
19008 Log delimiter string.
19011 Regular expression for detecting IP addresses. Use this instead of @code{column}.
19016 @node Networking Setup
19017 @subsection Networking Setup
19019 The @code{(gnu services networking)} module provides services to
19020 configure network interfaces and set up networking on your machine.
19021 Those services provide different ways for you to set up your machine: by
19022 declaring a static network configuration, by running a Dynamic Host
19023 Configuration Protocol (DHCP) client, or by running daemons such as
19024 NetworkManager and Connman that automate the whole process,
19025 automatically adapt to connectivity changes, and provide a high-level
19028 On a laptop, NetworkManager and Connman are by far the most convenient
19029 options, which is why the default desktop services include
19030 NetworkManager (@pxref{Desktop Services, @code{%desktop-services}}).
19031 For a server, or for a virtual machine or a container, static network
19032 configuration or a simple DHCP client are often more appropriate.
19034 This section describes the various network setup services available,
19035 starting with static network configuration.
19037 @defvr {Scheme Variable} static-networking-service-type
19038 This is the type for statically-configured network interfaces. Its
19039 value must be a list of @code{static-networking} records. Each of them
19040 declares a set of @dfn{addresses}, @dfn{routes}, and @dfn{links}, as
19043 @cindex network interface controller (NIC)
19044 @cindex NIC, networking interface controller
19045 Here is the simplest configuration, with only one network interface
19046 controller (NIC) and only IPv4 connectivity:
19049 ;; Static networking for one NIC, IPv4-only.
19050 (service static-networking-service-type
19051 (list (static-networking
19053 (list (network-address
19055 (value "10.0.2.15/24"))))
19057 (list (network-route
19058 (destination "default")
19059 (gateway "10.0.2.2"))))
19060 (name-servers '("10.0.2.3")))))
19063 The snippet above can be added to the @code{services} field of your
19064 operating system configuration (@pxref{Using the Configuration System}).
19065 It will configure your machine to have 10.0.2.15 as its IP address, with
19066 a 24-bit netmask for the local network---meaning that any 10.0.2.@var{x}
19067 address is on the local area network (LAN). Traffic to addresses
19068 outside the local network is routed @i{via} 10.0.2.2. Host names are
19069 resolved by sending domain name system (DNS) queries to 10.0.2.3.
19072 @deftp {Data Type} static-networking
19073 This is the data type representing a static network configuration.
19075 As an example, here is how you would declare the configuration of a
19076 machine with a single network interface controller (NIC) available as
19077 @code{eno1}, and with one IPv4 and one IPv6 address:
19080 ;; Network configuration for one NIC, IPv4 + IPv6.
19082 (addresses (list (network-address
19084 (value "10.0.2.15/24"))
19087 (value "2001:123:4567:101::1/64"))))
19088 (routes (list (network-route
19089 (destination "default")
19090 (gateway "10.0.2.2"))
19092 (destination "default")
19093 (gateway "2020:321:4567:42::1"))))
19094 (name-servers '("10.0.2.3")))
19097 If you are familiar with the @command{ip} command of the
19098 @uref{https://wiki.linuxfoundation.org/networking/iproute2,
19099 @code{iproute2} package} found on Linux-based systems, the declaration
19100 above is equivalent to typing:
19103 ip address add 10.0.2.15/24 dev eno1
19104 ip address add 2001:123:4567:101::1/64 dev eno1
19105 ip route add default via inet 10.0.2.2
19106 ip route add default via inet6 2020:321:4567:42::1
19109 Run @command{man 8 ip} for more info. Venerable GNU/Linux users will
19110 certainly know how to do it with @command{ifconfig} and @command{route},
19111 but we'll spare you that.
19113 The available fields of this data type are as follows:
19116 @item @code{addresses}
19117 @itemx @code{links} (default: @code{'()})
19118 @itemx @code{routes} (default: @code{'()})
19119 The list of @code{network-address}, @code{network-link}, and
19120 @code{network-route} records for this network (see below).
19122 @item @code{name-servers} (default: @code{'()})
19123 The list of IP addresses (strings) of domain name servers. These IP
19124 addresses go to @file{/etc/resolv.conf}.
19126 @item @code{provision} (default: @code{'(networking)})
19127 If true, this should be a list of symbols for the Shepherd service
19128 corresponding to this network configuration.
19130 @item @code{requirement} (default @code{'()})
19131 The list of Shepherd services depended on.
19135 @deftp {Data Type} network-address
19136 This is the data type representing the IP address of a network
19141 The name of the network interface for this address---e.g.,
19145 The actual IP address and network mask, in
19146 @uref{https://en.wikipedia.org/wiki/CIDR#CIDR_notation, @acronym{CIDR,
19147 Classless Inter-Domain Routing} notation}, as a string.
19149 For example, @code{"10.0.2.15/24"} denotes IPv4 address 10.0.2.15 on a
19150 24-bit sub-network---all 10.0.2.@var{x} addresses are on the same local
19154 Whether @code{value} denotes an IPv6 address. By default this is
19155 automatically determined.
19159 @deftp {Data Type} network-route
19160 This is the data type representing a network route.
19163 @item @code{destination}
19164 The route destination (a string), either an IP address or
19165 @code{"default"} to denote the default route.
19167 @item @code{source} (default: @code{#f})
19170 @item @code{device} (default: @code{#f})
19171 The device used for this route---e.g., @code{"eno2"}.
19173 @item @code{ipv6?} (default: auto)
19174 Whether this is an IPv6 route. By default this is automatically
19175 determined based on @code{destination} or @code{gateway}.
19177 @item @code{gateway} (default: @code{#f})
19178 IP address (a string) through which traffic is routed.
19182 @deftp {Data Type} network-link
19183 Data type for a network link (@pxref{Link,,, guile-netlink,
19184 Guile-Netlink Manual}).
19188 The name of the link---e.g., @code{"v0p0"}.
19191 A symbol denoting the type of the link---e.g., @code{'veth}.
19194 List of arguments for this type of link.
19198 @cindex loopback device
19199 @defvr {Scheme Variable} %loopback-static-networking
19200 This is the @code{static-networking} record representing the ``loopback
19201 device'', @code{lo}, for IP addresses 127.0.0.1 and ::1, and providing
19202 the @code{loopback} Shepherd service.
19205 @cindex networking, with QEMU
19206 @cindex QEMU, networking
19207 @defvr {Scheme Variable} %qemu-static-networking
19208 This is the @code{static-networking} record representing network setup
19209 when using QEMU's user-mode network stack on @code{eth0} (@pxref{Using
19210 the user mode network stack,,, QEMU, QEMU Documentation}).
19213 @cindex DHCP, networking service
19214 @defvr {Scheme Variable} dhcp-client-service-type
19215 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
19216 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
19217 is the DHCP client package to use, @code{isc-dhcp} by default.
19220 @cindex NetworkManager
19222 @defvr {Scheme Variable} network-manager-service-type
19223 This is the service type for the
19224 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
19225 service. The value for this service type is a
19226 @code{network-manager-configuration} record.
19228 This service is part of @code{%desktop-services} (@pxref{Desktop
19232 @deftp {Data Type} network-manager-configuration
19233 Data type representing the configuration of NetworkManager.
19236 @item @code{network-manager} (default: @code{network-manager})
19237 The NetworkManager package to use.
19239 @item @code{dns} (default: @code{"default"})
19240 Processing mode for DNS, which affects how NetworkManager uses the
19241 @code{resolv.conf} configuration file.
19245 NetworkManager will update @code{resolv.conf} to reflect the nameservers
19246 provided by currently active connections.
19249 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
19250 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
19251 then update @code{resolv.conf} to point to the local nameserver.
19253 With this setting, you can share your network connection. For example when
19254 you want to share your network connection to another laptop @i{via} an
19255 Ethernet cable, you can open @command{nm-connection-editor} and configure the
19256 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
19257 and reestablish the connection (or reboot).
19259 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
19260 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
19261 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
19262 browser on your host system, or connect to the VM @i{via} SSH
19263 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
19264 host-to-guest connection, run this command once:
19267 nmcli connection add type tun \
19268 connection.interface-name tap0 \
19269 tun.mode tap tun.owner $(id -u) \
19270 ipv4.method shared \
19271 ipv4.addresses 172.28.112.1/24
19274 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
19275 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
19276 @command{qemu-system-...}.
19279 NetworkManager will not modify @code{resolv.conf}.
19282 @item @code{vpn-plugins} (default: @code{'()})
19283 This is the list of available plugins for virtual private networks
19284 (VPNs). An example of this is the @code{network-manager-openvpn}
19285 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
19291 @deffn {Scheme Variable} connman-service-type
19292 This is the service type to run @url{https://01.org/connman,Connman},
19293 a network connection manager.
19295 Its value must be an
19296 @code{connman-configuration} record as in this example:
19299 (service connman-service-type
19300 (connman-configuration
19301 (disable-vpn? #t)))
19304 See below for details about @code{connman-configuration}.
19307 @deftp {Data Type} connman-configuration
19308 Data Type representing the configuration of connman.
19311 @item @code{connman} (default: @var{connman})
19312 The connman package to use.
19314 @item @code{disable-vpn?} (default: @code{#f})
19315 When true, disable connman's vpn plugin.
19319 @cindex WPA Supplicant
19320 @defvr {Scheme Variable} wpa-supplicant-service-type
19321 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
19322 supplicant}, an authentication daemon required to authenticate against
19323 encrypted WiFi or ethernet networks.
19326 @deftp {Data Type} wpa-supplicant-configuration
19327 Data type representing the configuration of WPA Supplicant.
19329 It takes the following parameters:
19332 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
19333 The WPA Supplicant package to use.
19335 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
19336 List of services that should be started before WPA Supplicant starts.
19338 @item @code{dbus?} (default: @code{#t})
19339 Whether to listen for requests on D-Bus.
19341 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
19342 Where to store the PID file.
19344 @item @code{interface} (default: @code{#f})
19345 If this is set, it must specify the name of a network interface that
19346 WPA supplicant will control.
19348 @item @code{config-file} (default: @code{#f})
19349 Optional configuration file to use.
19351 @item @code{extra-options} (default: @code{'()})
19352 List of additional command-line arguments to pass to the daemon.
19356 @cindex ModemManager
19357 Some networking devices such as modems require special care, and this is
19358 what the services below focus on.
19360 @defvr {Scheme Variable} modem-manager-service-type
19361 This is the service type for the
19362 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
19363 service. The value for this service type is a
19364 @code{modem-manager-configuration} record.
19366 This service is part of @code{%desktop-services} (@pxref{Desktop
19370 @deftp {Data Type} modem-manager-configuration
19371 Data type representing the configuration of ModemManager.
19374 @item @code{modem-manager} (default: @code{modem-manager})
19375 The ModemManager package to use.
19380 @cindex USB_ModeSwitch
19381 @cindex Modeswitching
19383 @defvr {Scheme Variable} usb-modeswitch-service-type
19384 This is the service type for the
19385 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
19386 service. The value for this service type is
19387 a @code{usb-modeswitch-configuration} record.
19389 When plugged in, some USB modems (and other USB devices) initially present
19390 themselves as a read-only storage medium and not as a modem. They need to be
19391 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
19392 installs udev rules to automatically modeswitch these devices when they are
19395 This service is part of @code{%desktop-services} (@pxref{Desktop
19399 @deftp {Data Type} usb-modeswitch-configuration
19400 Data type representing the configuration of USB_ModeSwitch.
19403 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
19404 The USB_ModeSwitch package providing the binaries for modeswitching.
19406 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
19407 The package providing the device data and udev rules file used by
19410 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
19411 Which config file to use for the USB_ModeSwitch dispatcher. By default the
19412 config file shipped with USB_ModeSwitch is used which disables logging to
19413 @file{/var/log} among other default settings. If set to @code{#f}, no config
19420 @node Networking Services
19421 @subsection Networking Services
19423 The @code{(gnu services networking)} module discussed in the previous
19424 section provides services for more advanced setups: providing a DHCP
19425 service for others to use, filtering packets with iptables or nftables,
19426 running a WiFi access point with @command{hostapd}, running the
19427 @command{inetd} ``superdaemon'', and more. This section describes
19430 @deffn {Scheme Procedure} dhcpd-service-type
19431 This type defines a service that runs a DHCP daemon. To create a
19432 service of this type, you must supply a @code{<dhcpd-configuration>}.
19436 (service dhcpd-service-type
19437 (dhcpd-configuration
19438 (config-file (local-file "my-dhcpd.conf"))
19439 (interfaces '("enp0s25"))))
19443 @deftp {Data Type} dhcpd-configuration
19445 @item @code{package} (default: @code{isc-dhcp})
19446 The package that provides the DHCP daemon. This package is expected to
19447 provide the daemon at @file{sbin/dhcpd} relative to its output
19448 directory. The default package is the
19449 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
19450 @item @code{config-file} (default: @code{#f})
19451 The configuration file to use. This is required. It will be passed to
19452 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
19453 object (@pxref{G-Expressions, file-like objects}). See @code{man
19454 dhcpd.conf} for details on the configuration file syntax.
19455 @item @code{version} (default: @code{"4"})
19456 The DHCP version to use. The ISC DHCP server supports the values ``4'',
19457 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
19458 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
19460 @item @code{run-directory} (default: @code{"/run/dhcpd"})
19461 The run directory to use. At service activation time, this directory
19462 will be created if it does not exist.
19463 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
19464 The PID file to use. This corresponds to the @code{-pf} option of
19465 @code{dhcpd}. See @code{man dhcpd} for details.
19466 @item @code{interfaces} (default: @code{'()})
19467 The names of the network interfaces on which dhcpd should listen for
19468 broadcasts. If this list is not empty, then its elements (which must be
19469 strings) will be appended to the @code{dhcpd} invocation when starting
19470 the daemon. It may not be necessary to explicitly specify any
19471 interfaces here; see @code{man dhcpd} for details.
19475 @cindex hostapd service, for Wi-Fi access points
19476 @cindex Wi-Fi access points, hostapd service
19477 @defvr {Scheme Variable} hostapd-service-type
19478 This is the service type to run the @uref{https://w1.fi/hostapd/,
19479 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
19480 authentication servers. Its associated value must be a
19481 @code{hostapd-configuration} as shown below:
19484 ;; Use wlan1 to run the access point for "My Network".
19485 (service hostapd-service-type
19486 (hostapd-configuration
19487 (interface "wlan1")
19488 (ssid "My Network")
19493 @deftp {Data Type} hostapd-configuration
19494 This data type represents the configuration of the hostapd service, with
19495 the following fields:
19498 @item @code{package} (default: @code{hostapd})
19499 The hostapd package to use.
19501 @item @code{interface} (default: @code{"wlan0"})
19502 The network interface to run the WiFi access point.
19505 The SSID (@dfn{service set identifier}), a string that identifies this
19508 @item @code{broadcast-ssid?} (default: @code{#t})
19509 Whether to broadcast this SSID.
19511 @item @code{channel} (default: @code{1})
19512 The WiFi channel to use.
19514 @item @code{driver} (default: @code{"nl80211"})
19515 The driver interface type. @code{"nl80211"} is used with all Linux
19516 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
19517 RADIUS server that does # not control any wireless/wired driver.
19519 @item @code{extra-settings} (default: @code{""})
19520 Extra settings to append as-is to the hostapd configuration file. See
19521 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
19522 configuration file reference.
19526 @defvr {Scheme Variable} simulated-wifi-service-type
19527 This is the type of a service to simulate WiFi networking, which can be
19528 useful in virtual machines for testing purposes. The service loads the
19530 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
19531 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
19532 network that can be seen on @code{wlan0}, by default.
19534 The service's value is a @code{hostapd-configuration} record.
19539 @defvr {Scheme Variable} iptables-service-type
19540 This is the service type to set up an iptables configuration. iptables is a
19541 packet filtering framework supported by the Linux kernel. This service
19542 supports configuring iptables for both IPv4 and IPv6. A simple example
19543 configuration rejecting all incoming connections except those to the ssh port
19547 (service iptables-service-type
19548 (iptables-configuration
19549 (ipv4-rules (plain-file "iptables.rules" "*filter
19553 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19554 -A INPUT -p tcp --dport 22 -j ACCEPT
19555 -A INPUT -j REJECT --reject-with icmp-port-unreachable
19558 (ipv6-rules (plain-file "ip6tables.rules" "*filter
19562 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19563 -A INPUT -p tcp --dport 22 -j ACCEPT
19564 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
19570 @deftp {Data Type} iptables-configuration
19571 The data type representing the configuration of iptables.
19574 @item @code{iptables} (default: @code{iptables})
19575 The iptables package that provides @code{iptables-restore} and
19576 @code{ip6tables-restore}.
19577 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
19578 The iptables rules to use. It will be passed to @code{iptables-restore}.
19579 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19581 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
19582 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
19583 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19589 @defvr {Scheme Variable} nftables-service-type
19590 This is the service type to set up a nftables configuration. nftables is a
19591 netfilter project that aims to replace the existing iptables, ip6tables,
19592 arptables and ebtables framework. It provides a new packet filtering
19593 framework, a new user-space utility @command{nft}, and a compatibility layer
19594 for iptables. This service comes with a default ruleset
19595 @code{%default-nftables-ruleset} that rejecting all incoming connections
19596 except those to the ssh port 22. To use it, simply write:
19599 (service nftables-service-type)
19603 @deftp {Data Type} nftables-configuration
19604 The data type representing the configuration of nftables.
19607 @item @code{package} (default: @code{nftables})
19608 The nftables package that provides @command{nft}.
19609 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
19610 The nftables ruleset to use. This may be any ``file-like'' object
19611 (@pxref{G-Expressions, file-like objects}).
19615 @cindex NTP (Network Time Protocol), service
19616 @cindex ntpd, service for the Network Time Protocol daemon
19617 @cindex real time clock
19618 @defvr {Scheme Variable} ntp-service-type
19619 This is the type of the service running the @uref{https://www.ntp.org,
19620 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
19621 system clock synchronized with that of the specified NTP servers.
19623 The value of this service is an @code{ntpd-configuration} object, as described
19627 @deftp {Data Type} ntp-configuration
19628 This is the data type for the NTP service configuration.
19631 @item @code{servers} (default: @code{%ntp-servers})
19632 This is the list of servers (@code{<ntp-server>} records) with which
19633 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
19636 @item @code{allow-large-adjustment?} (default: @code{#t})
19637 This determines whether @command{ntpd} is allowed to make an initial
19638 adjustment of more than 1,000 seconds.
19640 @item @code{ntp} (default: @code{ntp})
19641 The NTP package to use.
19645 @defvr {Scheme Variable} %ntp-servers
19646 List of host names used as the default NTP servers. These are servers of the
19647 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
19650 @deftp {Data Type} ntp-server
19651 The data type representing the configuration of a NTP server.
19654 @item @code{type} (default: @code{'server})
19655 The type of the NTP server, given as a symbol. One of @code{'pool},
19656 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
19658 @item @code{address}
19659 The address of the server, as a string.
19661 @item @code{options}
19662 NTPD options to use with that specific server, given as a list of option names
19663 and/or of option names and values tuples. The following example define a server
19664 to use with the options @option{iburst} and @option{prefer}, as well as
19665 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
19670 (address "some.ntp.server.org")
19671 (options `(iburst (version 3) (maxpoll 16) prefer))))
19677 @deffn {Scheme Procedure} openntpd-service-type
19678 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
19679 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
19680 clock synchronized with that of the given servers.
19684 openntpd-service-type
19685 (openntpd-configuration
19686 (listen-on '("127.0.0.1" "::1"))
19687 (sensor '("udcf0 correction 70000"))
19688 (constraint-from '("www.gnu.org"))
19689 (constraints-from '("https://www.google.com/"))))
19694 @defvr {Scheme Variable} %openntpd-servers
19695 This variable is a list of the server addresses defined in
19696 @code{%ntp-servers}.
19699 @deftp {Data Type} openntpd-configuration
19701 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
19702 The openntpd executable to use.
19703 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
19704 A list of local IP addresses or hostnames the ntpd daemon should listen on.
19705 @item @code{query-from} (default: @code{'()})
19706 A list of local IP address the ntpd daemon should use for outgoing queries.
19707 @item @code{sensor} (default: @code{'()})
19708 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
19709 will listen to each sensor that actually exists and ignore non-existent ones.
19710 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
19712 @item @code{server} (default: @code{'()})
19713 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
19714 @item @code{servers} (default: @code{%openntp-servers})
19715 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
19716 @item @code{constraint-from} (default: @code{'()})
19717 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
19718 This time information is not used for precision but acts as an authenticated
19719 constraint, thereby reducing the impact of unauthenticated NTP
19720 man-in-the-middle attacks.
19721 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
19723 @item @code{constraints-from} (default: @code{'()})
19724 As with constraint from, specify a list of URLs, IP addresses or hostnames of
19725 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
19726 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
19731 @deffn {Scheme variable} inetd-service-type
19732 This service runs the @command{inetd} (@pxref{inetd invocation,,,
19733 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
19734 connections on internet sockets, and lazily starts the specified server
19735 program when a connection is made on one of these sockets.
19737 The value of this service is an @code{inetd-configuration} object. The
19738 following example configures the @command{inetd} daemon to provide the
19739 built-in @command{echo} service, as well as an smtp service which
19740 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
19741 gateway @code{hostname}:
19746 (inetd-configuration
19750 (socket-type 'stream)
19757 (socket-type 'stream)
19761 (program (file-append openssh "/bin/ssh"))
19763 '("ssh" "-qT" "-i" "/path/to/ssh_key"
19764 "-W" "smtp-server:25" "user@@hostname")))))))
19767 See below for more details about @code{inetd-configuration}.
19770 @deftp {Data Type} inetd-configuration
19771 Data type representing the configuration of @command{inetd}.
19774 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
19775 The @command{inetd} executable to use.
19777 @item @code{entries} (default: @code{'()})
19778 A list of @command{inetd} service entries. Each entry should be created
19779 by the @code{inetd-entry} constructor.
19783 @deftp {Data Type} inetd-entry
19784 Data type representing an entry in the @command{inetd} configuration.
19785 Each entry corresponds to a socket where @command{inetd} will listen for
19789 @item @code{node} (default: @code{#f})
19790 Optional string, a comma-separated list of local addresses
19791 @command{inetd} should use when listening for this service.
19792 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
19793 description of all options.
19795 A string, the name must correspond to an entry in @code{/etc/services}.
19796 @item @code{socket-type}
19797 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
19799 @item @code{protocol}
19800 A string, must correspond to an entry in @code{/etc/protocols}.
19801 @item @code{wait?} (default: @code{#t})
19802 Whether @command{inetd} should wait for the server to exit before
19803 listening to new service requests.
19805 A string containing the user (and, optionally, group) name of the user
19806 as whom the server should run. The group name can be specified in a
19807 suffix, separated by a colon or period, i.e.@: @code{"user"},
19808 @code{"user:group"} or @code{"user.group"}.
19809 @item @code{program} (default: @code{"internal"})
19810 The server program which will serve the requests, or @code{"internal"}
19811 if @command{inetd} should use a built-in service.
19812 @item @code{arguments} (default: @code{'()})
19813 A list strings or file-like objects, which are the server program's
19814 arguments, starting with the zeroth argument, i.e.@: the name of the
19815 program itself. For @command{inetd}'s internal services, this entry
19816 must be @code{'()} or @code{'("internal")}.
19819 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
19820 detailed discussion of each configuration field.
19823 @cindex opendht, distributed hash table network service
19824 @cindex dhtproxy, for use with jami
19825 @defvr {Scheme Variable} opendht-service-type
19826 This is the type of the service running a @uref{https://opendht.net,
19827 OpenDHT} node, @command{dhtnode}. The daemon can be used to host your
19828 own proxy service to the distributed hash table (DHT), for example to
19829 connect to with Jami, among other applications.
19831 @quotation Important
19832 When using the OpenDHT proxy server, the IP addresses it ``sees'' from
19833 the clients should be addresses reachable from other peers. In practice
19834 this means that a publicly reachable address is best suited for a proxy
19835 server, outside of your private network. For example, hosting the proxy
19836 server on a IPv4 private local network and exposing it via port
19837 forwarding could work for external peers, but peers local to the proxy
19838 would have their private addresses shared with the external peers,
19839 leading to connectivity problems.
19842 The value of this service is a @code{opendht-configuration} object, as
19846 @c The fields documentation has been auto-generated using the
19847 @c configuration->documentation procedure from
19848 @c (gnu services configuration).
19849 @deftp {Data Type} opendht-configuration
19850 Available @code{opendht-configuration} fields are:
19853 @item @code{opendht} (default: @code{opendht}) (type: file-like)
19854 The @code{opendht} package to use.
19856 @item @code{peer-discovery?} (default: @code{#f}) (type: boolean)
19857 Whether to enable the multicast local peer discovery mechanism.
19859 @item @code{enable-logging?} (default: @code{#f}) (type: boolean)
19860 Whether to enable logging messages to syslog. It is disabled by default
19861 as it is rather verbose.
19863 @item @code{debug?} (default: @code{#f}) (type: boolean)
19864 Whether to enable debug-level logging messages. This has no effect if
19865 logging is disabled.
19867 @item @code{bootstrap-host} (default: @code{"bootstrap.jami.net:4222"}) (type: maybe-string)
19868 The node host name that is used to make the first connection to the
19869 network. A specific port value can be provided by appending the
19870 @code{:PORT} suffix. By default, it uses the Jami bootstrap nodes, but
19871 any host can be specified here. It's also possible to disable
19872 bootstrapping by explicitly setting this field to the
19873 @code{%unset-value} value.
19875 @item @code{port} (default: @code{4222}) (type: maybe-number)
19876 The UDP port to bind to. When left unspecified, an available port is
19877 automatically selected.
19879 @item @code{proxy-server-port} (type: maybe-number)
19880 Spawn a proxy server listening on the specified port.
19882 @item @code{proxy-server-port-tls} (type: maybe-number)
19883 Spawn a proxy server listening to TLS connections on the specified port.
19889 @defvr {Scheme Variable} tor-service-type
19890 This is the type for a service that runs the @uref{https://torproject.org,
19891 Tor} anonymous networking daemon. The service is configured using a
19892 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
19893 @code{tor} unprivileged user, which is a member of the @code{tor} group.
19897 @deftp {Data Type} tor-configuration
19899 @item @code{tor} (default: @code{tor})
19900 The package that provides the Tor daemon. This package is expected to provide
19901 the daemon at @file{bin/tor} relative to its output directory. The default
19902 package is the @uref{https://www.torproject.org, Tor Project's}
19905 @item @code{config-file} (default: @code{(plain-file "empty" "")})
19906 The configuration file to use. It will be appended to a default configuration
19907 file, and the final configuration file will be passed to @code{tor} via its
19908 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
19909 file-like objects}). See @code{man tor} for details on the configuration file
19912 @item @code{hidden-services} (default: @code{'()})
19913 The list of @code{<hidden-service>} records to use. For any hidden service
19914 you include in this list, appropriate configuration to enable the hidden
19915 service will be automatically added to the default configuration file. You
19916 may conveniently create @code{<hidden-service>} records using the
19917 @code{tor-hidden-service} procedure described below.
19919 @item @code{socks-socket-type} (default: @code{'tcp})
19920 The default socket type that Tor should use for its SOCKS socket. This must
19921 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
19922 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
19923 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
19924 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
19927 If you want to customize the SOCKS socket in more detail, leave
19928 @code{socks-socket-type} at its default value of @code{'tcp} and use
19929 @code{config-file} to override the default by providing your own
19930 @code{SocksPort} option.
19932 @item @code{control-socket?} (default: @code{#f})
19933 Whether or not to provide a ``control socket'' by which Tor can be
19934 controlled to, for instance, dynamically instantiate tor onion services.
19935 If @code{#t}, Tor will listen for control commands on the UNIX domain socket
19936 @file{/var/run/tor/control-sock}, which will be made writable by members of the
19942 @cindex hidden service
19943 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
19944 Define a new Tor @dfn{hidden service} called @var{name} and implementing
19945 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
19948 '((22 "127.0.0.1:22")
19949 (80 "127.0.0.1:8080"))
19952 In this example, port 22 of the hidden service is mapped to local port 22, and
19953 port 80 is mapped to local port 8080.
19955 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
19956 the @file{hostname} file contains the @code{.onion} host name for the hidden
19959 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
19960 project's documentation} for more information.
19963 The @code{(gnu services rsync)} module provides the following services:
19965 You might want an rsync daemon if you have files that you want available
19966 so anyone (or just yourself) can download existing files or upload new
19969 @deffn {Scheme Variable} rsync-service-type
19970 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
19971 The value for this service type is a
19972 @command{rsync-configuration} record as in this example:
19975 ;; Export two directories over rsync. By default rsync listens on
19976 ;; all the network interfaces.
19977 (service rsync-service-type
19978 (rsync-configuration
19979 (modules (list (rsync-module
19981 (file-name "/srv/zik")
19985 (file-name "/home/charlie/movies"))))))
19988 See below for details about @code{rsync-configuration}.
19991 @deftp {Data Type} rsync-configuration
19992 Data type representing the configuration for @code{rsync-service}.
19995 @item @code{package} (default: @var{rsync})
19996 @code{rsync} package to use.
19998 @item @code{address} (default: @code{#f})
19999 IP address on which @command{rsync} listens for incoming connections.
20000 If unspecified, it defaults to listening on all available addresses.
20002 @item @code{port-number} (default: @code{873})
20003 TCP port on which @command{rsync} listens for incoming connections. If port
20004 is less than @code{1024} @command{rsync} needs to be started as the
20005 @code{root} user and group.
20007 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
20008 Name of the file where @command{rsync} writes its PID.
20010 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
20011 Name of the file where @command{rsync} writes its lock file.
20013 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
20014 Name of the file where @command{rsync} writes its log file.
20016 @item @code{user} (default: @code{"root"})
20017 Owner of the @code{rsync} process.
20019 @item @code{group} (default: @code{"root"})
20020 Group of the @code{rsync} process.
20022 @item @code{uid} (default: @code{"rsyncd"})
20023 User name or user ID that file transfers to and from that module should take
20024 place as when the daemon was run as @code{root}.
20026 @item @code{gid} (default: @code{"rsyncd"})
20027 Group name or group ID that will be used when accessing the module.
20029 @item @code{modules} (default: @code{%default-modules})
20030 List of ``modules''---i.e., directories exported over rsync. Each
20031 element must be a @code{rsync-module} record, as described below.
20035 @deftp {Data Type} rsync-module
20036 This is the data type for rsync ``modules''. A module is a directory
20037 exported over the rsync protocol. The available fields are as follows:
20041 The module name. This is the name that shows up in URLs. For example,
20042 if the module is called @code{music}, the corresponding URL will be
20043 @code{rsync://host.example.org/music}.
20045 @item @code{file-name}
20046 Name of the directory being exported.
20048 @item @code{comment} (default: @code{""})
20049 Comment associated with the module. Client user interfaces may display
20050 it when they obtain the list of available modules.
20052 @item @code{read-only?} (default: @code{#t})
20053 Whether or not client will be able to upload files. If this is false,
20054 the uploads will be authorized if permissions on the daemon side permit
20057 @item @code{chroot?} (default: @code{#t})
20058 When this is true, the rsync daemon changes root to the module's
20059 directory before starting file transfers with the client. This improves
20060 security, but requires rsync to run as root.
20062 @item @code{timeout} (default: @code{300})
20063 Idle time in seconds after which the daemon closes a connection with the
20068 The @code{(gnu services syncthing)} module provides the following services:
20071 You might want a syncthing daemon if you have files between two or more
20072 computers and want to sync them in real time, safely protected from
20075 @deffn {Scheme Variable} syncthing-service-type
20076 This is the service type for the @uref{https://syncthing.net/,
20077 syncthing} daemon, The value for this service type is a
20078 @command{syncthing-configuration} record as in this example:
20081 (service syncthing-service-type
20082 (syncthing-configuration (user "alice")))
20085 See below for details about @code{syncthing-configuration}.
20087 @deftp {Data Type} syncthing-configuration
20088 Data type representing the configuration for @code{syncthing-service-type}.
20091 @item @code{syncthing} (default: @var{syncthing})
20092 @code{syncthing} package to use.
20094 @item @code{arguments} (default: @var{'()})
20095 List of command-line arguments passing to @code{syncthing} binary.
20097 @item @code{logflags} (default: @var{0})
20098 Sum of logging flags, see
20099 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
20101 @item @code{user} (default: @var{#f})
20102 The user as which the Syncthing service is to be run.
20103 This assumes that the specified user exists.
20105 @item @code{group} (default: @var{"users"})
20106 The group as which the Syncthing service is to be run.
20107 This assumes that the specified group exists.
20109 @item @code{home} (default: @var{#f})
20110 Common configuration and data directory. The default configuration
20111 directory is @file{$HOME} of the specified Syncthing @code{user}.
20117 Furthermore, @code{(gnu services ssh)} provides the following services.
20121 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
20122 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
20123 [#:allow-empty-passwords? #f] [#:root-login? #f] @
20124 [#:syslog-output? #t] [#:x11-forwarding? #t] @
20125 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
20126 [#:public-key-authentication? #t] [#:initialize? #t]
20127 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
20128 @var{host-key} must designate a file containing the host key, and readable
20131 When @var{daemonic?} is true, @command{lshd} will detach from the
20132 controlling terminal and log its output to syslogd, unless one sets
20133 @var{syslog-output?} to false. Obviously, it also makes lsh-service
20134 depend on existence of syslogd service. When @var{pid-file?} is true,
20135 @command{lshd} writes its PID to the file called @var{pid-file}.
20137 When @var{initialize?} is true, automatically create the seed and host key
20138 upon service activation if they do not exist yet. This may take long and
20139 require interaction.
20141 When @var{initialize?} is false, it is up to the user to initialize the
20142 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
20143 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
20144 basics,,, lsh, LSH Manual}).
20146 When @var{interfaces} is empty, lshd listens for connections on all the
20147 network interfaces; otherwise, @var{interfaces} must be a list of host names
20150 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
20151 passwords, and @var{root-login?} specifies whether to accept log-ins as
20154 The other options should be self-descriptive.
20159 @deffn {Scheme Variable} openssh-service-type
20160 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
20161 shell daemon, @command{sshd}. Its value must be an
20162 @code{openssh-configuration} record as in this example:
20165 (service openssh-service-type
20166 (openssh-configuration
20167 (x11-forwarding? #t)
20168 (permit-root-login 'prohibit-password)
20170 `(("alice" ,(local-file "alice.pub"))
20171 ("bob" ,(local-file "bob.pub"))))))
20174 See below for details about @code{openssh-configuration}.
20176 This service can be extended with extra authorized keys, as in this
20180 (service-extension openssh-service-type
20181 (const `(("charlie"
20182 ,(local-file "charlie.pub")))))
20186 @deftp {Data Type} openssh-configuration
20187 This is the configuration record for OpenSSH's @command{sshd}.
20190 @item @code{openssh} (default @var{openssh})
20191 The OpenSSH package to use.
20193 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
20194 Name of the file where @command{sshd} writes its PID.
20196 @item @code{port-number} (default: @code{22})
20197 TCP port on which @command{sshd} listens for incoming connections.
20199 @item @code{max-connections} (default: @code{200})
20200 Hard limit on the maximum number of simultaneous client connections,
20201 enforced by the inetd-style Shepherd service (@pxref{Service De- and
20202 Constructors, @code{make-inetd-constructor},, shepherd, The GNU Shepherd
20205 @item @code{permit-root-login} (default: @code{#f})
20206 This field determines whether and when to allow logins as root. If
20207 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
20208 If it's the symbol @code{'prohibit-password}, then root logins are
20209 permitted but not with password-based authentication.
20211 @item @code{allow-empty-passwords?} (default: @code{#f})
20212 When true, users with empty passwords may log in. When false, they may
20215 @item @code{password-authentication?} (default: @code{#t})
20216 When true, users may log in with their password. When false, they have
20217 other authentication methods.
20219 @item @code{public-key-authentication?} (default: @code{#t})
20220 When true, users may log in using public key authentication. When
20221 false, users have to use other authentication method.
20223 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
20224 This is used only by protocol version 2.
20226 @item @code{x11-forwarding?} (default: @code{#f})
20227 When true, forwarding of X11 graphical client connections is
20228 enabled---in other words, @command{ssh} options @option{-X} and
20229 @option{-Y} will work.
20231 @item @code{allow-agent-forwarding?} (default: @code{#t})
20232 Whether to allow agent forwarding.
20234 @item @code{allow-tcp-forwarding?} (default: @code{#t})
20235 Whether to allow TCP forwarding.
20237 @item @code{gateway-ports?} (default: @code{#f})
20238 Whether to allow gateway ports.
20240 @item @code{challenge-response-authentication?} (default: @code{#f})
20241 Specifies whether challenge response authentication is allowed (e.g.@: via
20244 @item @code{use-pam?} (default: @code{#t})
20245 Enables the Pluggable Authentication Module interface. If set to
20246 @code{#t}, this will enable PAM authentication using
20247 @code{challenge-response-authentication?} and
20248 @code{password-authentication?}, in addition to PAM account and session
20249 module processing for all authentication types.
20251 Because PAM challenge response authentication usually serves an
20252 equivalent role to password authentication, you should disable either
20253 @code{challenge-response-authentication?} or
20254 @code{password-authentication?}.
20256 @item @code{print-last-log?} (default: @code{#t})
20257 Specifies whether @command{sshd} should print the date and time of the
20258 last user login when a user logs in interactively.
20260 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
20261 Configures external subsystems (e.g.@: file transfer daemon).
20263 This is a list of two-element lists, each of which containing the
20264 subsystem name and a command (with optional arguments) to execute upon
20267 The command @command{internal-sftp} implements an in-process SFTP
20268 server. Alternatively, one can specify the @command{sftp-server} command:
20270 (service openssh-service-type
20271 (openssh-configuration
20273 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
20276 @item @code{accepted-environment} (default: @code{'()})
20277 List of strings describing which environment variables may be exported.
20279 Each string gets on its own line. See the @code{AcceptEnv} option in
20280 @code{man sshd_config}.
20282 This example allows ssh-clients to export the @env{COLORTERM} variable.
20283 It is set by terminal emulators, which support colors. You can use it in
20284 your shell's resource file to enable colors for the prompt and commands
20285 if this variable is set.
20288 (service openssh-service-type
20289 (openssh-configuration
20290 (accepted-environment '("COLORTERM"))))
20293 @item @code{authorized-keys} (default: @code{'()})
20294 @cindex authorized keys, SSH
20295 @cindex SSH authorized keys
20296 This is the list of authorized keys. Each element of the list is a user
20297 name followed by one or more file-like objects that represent SSH public
20301 (openssh-configuration
20303 `(("rekado" ,(local-file "rekado.pub"))
20304 ("chris" ,(local-file "chris.pub"))
20305 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
20309 registers the specified public keys for user accounts @code{rekado},
20310 @code{chris}, and @code{root}.
20312 Additional authorized keys can be specified @i{via}
20313 @code{service-extension}.
20315 Note that this does @emph{not} interfere with the use of
20316 @file{~/.ssh/authorized_keys}.
20318 @item @code{generate-host-keys?} (default: @code{#t})
20319 Whether to generate host key pairs with @command{ssh-keygen -A} under
20320 @file{/etc/ssh} if there are none.
20322 Generating key pairs takes a few seconds when enough entropy is
20323 available and is only done once. You might want to turn it off for
20324 instance in a virtual machine that does not need it because host keys
20325 are provided in some other way, and where the extra boot time is a
20328 @item @code{log-level} (default: @code{'info})
20329 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
20330 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
20331 page for @file{sshd_config} for the full list of level names.
20333 @item @code{extra-content} (default: @code{""})
20334 This field can be used to append arbitrary text to the configuration file. It
20335 is especially useful for elaborate configurations that cannot be expressed
20336 otherwise. This configuration, for example, would generally disable root
20337 logins, but permit them from one specific IP address:
20340 (openssh-configuration
20342 Match Address 192.168.0.1
20343 PermitRootLogin yes"))
20349 @deffn {Scheme Procedure} dropbear-service [@var{config}]
20350 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
20351 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
20354 For example, to specify a Dropbear service listening on port 1234, add
20355 this call to the operating system's @code{services} field:
20358 (dropbear-service (dropbear-configuration
20359 (port-number 1234)))
20363 @deftp {Data Type} dropbear-configuration
20364 This data type represents the configuration of a Dropbear SSH daemon.
20367 @item @code{dropbear} (default: @var{dropbear})
20368 The Dropbear package to use.
20370 @item @code{port-number} (default: 22)
20371 The TCP port where the daemon waits for incoming connections.
20373 @item @code{syslog-output?} (default: @code{#t})
20374 Whether to enable syslog output.
20376 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
20377 File name of the daemon's PID file.
20379 @item @code{root-login?} (default: @code{#f})
20380 Whether to allow @code{root} logins.
20382 @item @code{allow-empty-passwords?} (default: @code{#f})
20383 Whether to allow empty passwords.
20385 @item @code{password-authentication?} (default: @code{#t})
20386 Whether to enable password-based authentication.
20391 @deffn {Scheme Variable} autossh-service-type
20392 This is the type for the @uref{https://www.harding.motd.ca/autossh,
20393 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
20394 restarting it as necessary should it die or stop passing traffic.
20395 AutoSSH can be run manually from the command-line by passing arguments
20396 to the binary @command{autossh} from the package @code{autossh}, but it
20397 can also be run as a Guix service. This latter use case is documented
20400 AutoSSH can be used to forward local traffic to a remote machine using
20401 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
20404 For example, to specify a service running autossh as the user
20405 @code{pino} and forwarding all local connections to port @code{8081} to
20406 @code{remote:8081} using an SSH tunnel, add this call to the operating
20407 system's @code{services} field:
20410 (service autossh-service-type
20411 (autossh-configuration
20413 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
20417 @deftp {Data Type} autossh-configuration
20418 This data type represents the configuration of an AutoSSH service.
20422 @item @code{user} (default @code{"autossh"})
20423 The user as which the AutoSSH service is to be run.
20424 This assumes that the specified user exists.
20426 @item @code{poll} (default @code{600})
20427 Specifies the connection poll time in seconds.
20429 @item @code{first-poll} (default @code{#f})
20430 Specifies how many seconds AutoSSH waits before the first connection
20431 test. After this first test, polling is resumed at the pace defined in
20432 @code{poll}. When set to @code{#f}, the first poll is not treated
20433 specially and will also use the connection poll specified in
20436 @item @code{gate-time} (default @code{30})
20437 Specifies how many seconds an SSH connection must be active before it is
20438 considered successful.
20440 @item @code{log-level} (default @code{1})
20441 The log level, corresponding to the levels used by syslog---so @code{0}
20442 is the most silent while @code{7} is the chattiest.
20444 @item @code{max-start} (default @code{#f})
20445 The maximum number of times SSH may be (re)started before AutoSSH exits.
20446 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
20448 @item @code{message} (default @code{""})
20449 The message to append to the echo message sent when testing connections.
20451 @item @code{port} (default @code{"0"})
20452 The ports used for monitoring the connection. When set to @code{"0"},
20453 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
20454 a positive integer, ports @var{n} and @var{n}+1 are used for
20455 monitoring the connection, such that port @var{n} is the base
20456 monitoring port and @code{n+1} is the echo port. When set to
20457 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
20458 integers, the ports @var{n} and @var{m} are used for monitoring the
20459 connection, such that port @var{n} is the base monitoring port and
20460 @var{m} is the echo port.
20462 @item @code{ssh-options} (default @code{'()})
20463 The list of command-line arguments to pass to @command{ssh} when it is
20464 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
20465 may cause undefined behaviour.
20471 @deffn {Scheme Variable} webssh-service-type
20472 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
20473 program that runs a web SSH client. WebSSH can be run manually from the
20474 command-line by passing arguments to the binary @command{wssh} from the
20475 package @code{webssh}, but it can also be run as a Guix service. This
20476 latter use case is documented here.
20478 For example, to specify a service running WebSSH on loopback interface
20479 on port @code{8888} with reject policy with a list of allowed to
20480 connection hosts, and NGINX as a reverse-proxy to this service listening
20481 for HTTPS connection, add this call to the operating system's
20482 @code{services} field:
20485 (service webssh-service-type
20486 (webssh-configuration (address "127.0.0.1")
20489 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
20490 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
20492 (service nginx-service-type
20493 (nginx-configuration
20496 (nginx-server-configuration
20497 (inherit %webssh-configuration-nginx)
20498 (server-name '("webssh.example.com"))
20499 (listen '("443 ssl"))
20500 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
20501 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
20503 (cons (nginx-location-configuration
20504 (uri "/.well-known")
20505 (body '("root /var/www;")))
20506 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
20510 @deftp {Data Type} webssh-configuration
20511 Data type representing the configuration for @code{webssh-service}.
20514 @item @code{package} (default: @var{webssh})
20515 @code{webssh} package to use.
20517 @item @code{user-name} (default: @var{"webssh"})
20518 User name or user ID that file transfers to and from that module should take
20521 @item @code{group-name} (default: @var{"webssh"})
20522 Group name or group ID that will be used when accessing the module.
20524 @item @code{address} (default: @var{#f})
20525 IP address on which @command{webssh} listens for incoming connections.
20527 @item @code{port} (default: @var{8888})
20528 TCP port on which @command{webssh} listens for incoming connections.
20530 @item @code{policy} (default: @var{#f})
20531 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
20533 @item @code{known-hosts} (default: @var{'()})
20534 List of hosts which allowed for SSH connection from @command{webssh}.
20536 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
20537 Name of the file where @command{webssh} writes its log file.
20539 @item @code{log-level} (default: @var{#f})
20545 @defvr {Scheme Variable} %facebook-host-aliases
20546 This variable contains a string for use in @file{/etc/hosts}
20547 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
20548 line contains a entry that maps a known server name of the Facebook
20549 on-line service---e.g., @code{www.facebook.com}---to the local
20550 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
20552 This variable is typically used in the @code{hosts-file} field of an
20553 @code{operating-system} declaration (@pxref{operating-system Reference,
20554 @file{/etc/hosts}}):
20557 (use-modules (gnu) (guix))
20560 (host-name "mymachine")
20563 ;; Create a /etc/hosts file with aliases for "localhost"
20564 ;; and "mymachine", as well as for Facebook servers.
20565 (plain-file "hosts"
20566 (string-append (local-host-aliases host-name)
20567 %facebook-host-aliases))))
20570 This mechanism can prevent programs running locally, such as Web
20571 browsers, from accessing Facebook.
20574 The @code{(gnu services avahi)} provides the following definition.
20576 @defvr {Scheme Variable} avahi-service-type
20577 This is the service that runs @command{avahi-daemon}, a system-wide
20578 mDNS/DNS-SD responder that allows for service discovery and
20579 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
20580 Its value must be an @code{avahi-configuration} record---see below.
20582 This service extends the name service cache daemon (nscd) so that it can
20583 resolve @code{.local} host names using
20584 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
20585 Service Switch}, for information on host name resolution.
20587 Additionally, add the @var{avahi} package to the system profile so that
20588 commands such as @command{avahi-browse} are directly usable.
20591 @deftp {Data Type} avahi-configuration
20592 Data type representation the configuration for Avahi.
20596 @item @code{host-name} (default: @code{#f})
20597 If different from @code{#f}, use that as the host name to
20598 publish for this machine; otherwise, use the machine's actual host name.
20600 @item @code{publish?} (default: @code{#t})
20601 When true, allow host names and services to be published (broadcast) over the
20604 @item @code{publish-workstation?} (default: @code{#t})
20605 When true, @command{avahi-daemon} publishes the machine's host name and IP
20606 address via mDNS on the local network. To view the host names published on
20607 your local network, you can run:
20610 avahi-browse _workstation._tcp
20613 @item @code{wide-area?} (default: @code{#f})
20614 When true, DNS-SD over unicast DNS is enabled.
20616 @item @code{ipv4?} (default: @code{#t})
20617 @itemx @code{ipv6?} (default: @code{#t})
20618 These fields determine whether to use IPv4/IPv6 sockets.
20620 @item @code{domains-to-browse} (default: @code{'()})
20621 This is a list of domains to browse.
20625 @deffn {Scheme Variable} openvswitch-service-type
20626 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
20627 service, whose value should be an @code{openvswitch-configuration}
20631 @deftp {Data Type} openvswitch-configuration
20632 Data type representing the configuration of Open vSwitch, a multilayer
20633 virtual switch which is designed to enable massive network automation
20634 through programmatic extension.
20637 @item @code{package} (default: @var{openvswitch})
20638 Package object of the Open vSwitch.
20643 @defvr {Scheme Variable} pagekite-service-type
20644 This is the service type for the @uref{https://pagekite.net, PageKite} service,
20645 a tunneling solution for making localhost servers publicly visible, even from
20646 behind restrictive firewalls or NAT without forwarded ports. The value for
20647 this service type is a @code{pagekite-configuration} record.
20649 Here's an example exposing the local HTTP and SSH daemons:
20652 (service pagekite-service-type
20653 (pagekite-configuration
20654 (kites '("http:@@kitename:localhost:80:@@kitesecret"
20655 "raw/22:@@kitename:localhost:22:@@kitesecret"))
20656 (extra-file "/etc/pagekite.rc")))
20660 @deftp {Data Type} pagekite-configuration
20661 Data type representing the configuration of PageKite.
20664 @item @code{package} (default: @var{pagekite})
20665 Package object of PageKite.
20667 @item @code{kitename} (default: @code{#f})
20668 PageKite name for authenticating to the frontend server.
20670 @item @code{kitesecret} (default: @code{#f})
20671 Shared secret for authenticating to the frontend server. You should probably
20672 put this inside @code{extra-file} instead.
20674 @item @code{frontend} (default: @code{#f})
20675 Connect to the named PageKite frontend server instead of the
20676 @uref{https://pagekite.net,,pagekite.net} service.
20678 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
20679 List of service kites to use. Exposes HTTP on port 80 by default. The format
20680 is @code{proto:kitename:host:port:secret}.
20682 @item @code{extra-file} (default: @code{#f})
20683 Extra configuration file to read, which you are expected to create manually.
20684 Use this to add additional options and manage shared secrets out-of-band.
20689 @defvr {Scheme Variable} yggdrasil-service-type
20690 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
20691 Yggdrasil network}, an early-stage implementation of a fully end-to-end
20692 encrypted IPv6 network.
20695 Yggdrasil provides name-independent routing with cryptographically generated
20696 addresses. Static addressing means you can keep the same address as long as
20697 you want, even if you move to a new location, or generate a new address (by
20698 generating new keys) whenever you want.
20699 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
20702 Pass it a value of @code{yggdrasil-configuration} to connect it to public
20703 peers and/or local peers.
20705 Here is an example using public peers and a static address. The static
20706 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
20707 (the default value for @code{config-file}).
20710 ;; part of the operating-system declaration
20711 (service yggdrasil-service-type
20712 (yggdrasil-configuration
20713 (autoconf? #f) ;; use only the public peers
20716 ;; https://github.com/yggdrasil-network/public-peers
20717 '((peers . #("tcp://1.2.3.4:1337"))))
20718 ;; /etc/yggdrasil-private.conf is the default value for config-file
20722 # sample content for /etc/yggdrasil-private.conf
20724 # Your public key. Your peers may ask you for this to put
20725 # into their AllowedPublicKeys configuration.
20726 PublicKey: 64277...
20728 # Your private key. DO NOT share this with anyone!
20729 PrivateKey: 5c750...
20734 @deftp {Data Type} yggdrasil-configuration
20735 Data type representing the configuration of Yggdrasil.
20738 @item @code{package} (default: @code{yggdrasil})
20739 Package object of Yggdrasil.
20741 @item @code{json-config} (default: @code{'()})
20742 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
20743 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
20744 the Guix store, which is readable to all users. @strong{Do not store your
20745 private keys in it}. See the output of @code{yggdrasil -genconf} for a
20746 quick overview of valid keys and their default values.
20748 @item @code{autoconf?} (default: @code{#f})
20749 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
20750 and peer with IPv6 neighbors.
20752 @item @code{log-level} (default: @code{'info})
20753 How much detail to include in logs. Use @code{'debug} for more detail.
20755 @item @code{log-to} (default: @code{'stdout})
20756 Where to send logs. By default, the service logs standard output to
20757 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
20758 sends output to the running syslog service.
20760 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
20761 What HJSON file to load sensitive data from. This is where private keys
20762 should be stored, which are necessary to specify if you don't want a
20763 randomized address after each restart. Use @code{#f} to disable. Options
20764 defined in this file take precedence over @code{json-config}. Use the output
20765 of @code{yggdrasil -genconf} as a starting point. To configure a static
20766 address, delete everything except these options:
20769 @item @code{EncryptionPublicKey}
20770 @item @code{EncryptionPrivateKey}
20771 @item @code{SigningPublicKey}
20772 @item @code{SigningPrivateKey}
20778 @defvr {Scheme Variable} ipfs-service-type
20779 The service type for connecting to the @uref{https://ipfs.io,IPFS network},
20780 a global, versioned, peer-to-peer file system. Pass it a
20781 @code{ipfs-configuration} to change the ports used for the gateway and API.
20783 Here's an example configuration, using some non-standard ports:
20786 (service ipfs-service-type
20787 (ipfs-configuration
20788 (gateway "/ip4/127.0.0.1/tcp/8880")
20789 (api "/ip4/127.0.0.1/tcp/8881")))
20793 @deftp {Data Type} ipfs-configuration
20794 Data type representing the configuration of IPFS.
20797 @item @code{package} (default: @code{go-ipfs})
20798 Package object of IPFS.
20800 @item @code{gateway} (default: @code{"/ip4/127.0.0.1/tcp/8082"})
20801 Address of the gateway, in ‘multiaddress’ format.
20803 @item @code{api} (default: @code{"/ip4/127.0.0.1/tcp/5001"})
20804 Address of the API endpoint, in ‘multiaddress’ format.
20809 @deffn {Scheme Variable} keepalived-service-type
20810 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
20811 routing software, @command{keepalived}. Its value must be an
20812 @code{keepalived-configuration} record as in this example for master
20816 (service keepalived-service-type
20817 (keepalived-configuration
20818 (config-file (local-file "keepalived-master.conf"))))
20821 where @file{keepalived-master.conf}:
20824 vrrp_instance my-group @{
20827 virtual_router_id 100
20829 unicast_peer @{ 10.0.0.2 @}
20830 virtual_ipaddress @{
20836 and for backup machine:
20839 (service keepalived-service-type
20840 (keepalived-configuration
20841 (config-file (local-file "keepalived-backup.conf"))))
20844 where @file{keepalived-backup.conf}:
20847 vrrp_instance my-group @{
20850 virtual_router_id 100
20852 unicast_peer @{ 10.0.0.3 @}
20853 virtual_ipaddress @{
20860 @node Unattended Upgrades
20861 @subsection Unattended Upgrades
20863 @cindex unattended upgrades
20864 @cindex upgrades, unattended
20865 Guix provides a service to perform @emph{unattended upgrades}:
20866 periodically, the system automatically reconfigures itself from the
20867 latest Guix. Guix System has several properties that make unattended
20872 upgrades are transactional (either the upgrade succeeds or it fails, but
20873 you cannot end up with an ``in-between'' system state);
20875 the upgrade log is kept---you can view it with @command{guix system
20876 list-generations}---and you can roll back to any previous generation,
20877 should the upgraded system fail to behave as intended;
20879 channel code is authenticated so you know you can only run genuine code
20880 (@pxref{Channels});
20882 @command{guix system reconfigure} prevents downgrades, which makes it
20883 immune to @dfn{downgrade attacks}.
20886 To set up unattended upgrades, add an instance of
20887 @code{unattended-upgrade-service-type} like the one below to the list of
20888 your operating system services:
20891 (service unattended-upgrade-service-type)
20894 The defaults above set up weekly upgrades: every Sunday at midnight.
20895 You do not need to provide the operating system configuration file: it
20896 uses @file{/run/current-system/configuration.scm}, which ensures it
20897 always uses your latest configuration---@pxref{provenance-service-type},
20898 for more information about this file.
20900 There are several things that can be configured, in particular the
20901 periodicity and services (daemons) to be restarted upon completion.
20902 When the upgrade is successful, the service takes care of deleting
20903 system generations older that some threshold, as per @command{guix
20904 system delete-generations}. See the reference below for details.
20906 To ensure that upgrades are actually happening, you can run
20907 @command{guix system describe}. To investigate upgrade failures, visit
20908 the unattended upgrade log file (see below).
20910 @defvr {Scheme Variable} unattended-upgrade-service-type
20911 This is the service type for unattended upgrades. It sets up an mcron
20912 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
20913 reconfigure} from the latest version of the specified channels.
20915 Its value must be a @code{unattended-upgrade-configuration} record (see
20919 @deftp {Data Type} unattended-upgrade-configuration
20920 This data type represents the configuration of the unattended upgrade
20921 service. The following fields are available:
20924 @item @code{schedule} (default: @code{"30 01 * * 0"})
20925 This is the schedule of upgrades, expressed as a gexp containing an
20926 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
20927 mcron, GNU@tie{}mcron}).
20929 @item @code{channels} (default: @code{#~%default-channels})
20930 This gexp specifies the channels to use for the upgrade
20931 (@pxref{Channels}). By default, the tip of the official @code{guix}
20934 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
20935 This field specifies the operating system configuration file to use.
20936 The default is to reuse the config file of the current configuration.
20938 There are cases, though, where referring to
20939 @file{/run/current-system/configuration.scm} is not enough, for instance
20940 because that file refers to extra files (SSH public keys, extra
20941 configuration files, etc.) @i{via} @code{local-file} and similar
20942 constructs. For those cases, we recommend something along these lines:
20945 (unattended-upgrade-configuration
20946 (operating-system-file
20947 (file-append (local-file "." "config-dir" #:recursive? #t)
20951 The effect here is to import all of the current directory into the
20952 store, and to refer to @file{config.scm} within that directory.
20953 Therefore, uses of @code{local-file} within @file{config.scm} will work
20954 as expected. @xref{G-Expressions}, for information about
20955 @code{local-file} and @code{file-append}.
20957 @item @code{services-to-restart} (default: @code{'(mcron)})
20958 This field specifies the Shepherd services to restart when the upgrade
20961 Those services are restarted right away upon completion, as with
20962 @command{herd restart}, which ensures that the latest version is
20963 running---remember that by default @command{guix system reconfigure}
20964 only restarts services that are not currently running, which is
20965 conservative: it minimizes disruption but leaves outdated services
20968 Use @command{herd status} to find out candidates for restarting.
20969 @xref{Services}, for general information about services. Common
20970 services to restart would include @code{ntpd} and @code{ssh-daemon}.
20972 By default, the @code{mcron} service is restarted. This ensures that
20973 the latest version of the unattended upgrade job will be used next time.
20975 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
20976 This is the expiration time in seconds for system generations. System
20977 generations older that this amount of time are deleted with
20978 @command{guix system delete-generations} when an upgrade completes.
20981 The unattended upgrade service does not run the garbage collector. You
20982 will probably want to set up your own mcron job to run @command{guix gc}
20986 @item @code{maximum-duration} (default: @code{3600})
20987 Maximum duration in seconds for the upgrade; past that time, the upgrade
20990 This is primarily useful to ensure the upgrade does not end up
20991 rebuilding or re-downloading ``the world''.
20993 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
20994 File where unattended upgrades are logged.
20999 @subsection X Window
21002 @cindex X Window System
21003 @cindex login manager
21004 Support for the X Window graphical display system---specifically
21005 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
21006 there is no @code{xorg-service} procedure. Instead, the X server is
21007 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
21010 @cindex GNOME, login manager
21011 GDM of course allows users to log in into window managers and desktop
21012 environments other than GNOME; for those using GNOME, GDM is required for
21013 features such as automatic screen locking.
21015 @cindex window manager
21016 To use X11, you must install at least one @dfn{window manager}---for
21017 example the @code{windowmaker} or @code{openbox} packages---preferably
21018 by adding it to the @code{packages} field of your operating system
21019 definition (@pxref{operating-system Reference, system-wide packages}).
21021 @anchor{wayland-gdm}
21022 GDM also supports Wayland: it can itself use Wayland instead of X11 for
21023 its user interface, and it can also start Wayland sessions. The former is
21024 required for the latter, to enable, set @code{wayland?} to @code{#t} in
21025 @code{gdm-configuration}.
21027 @defvr {Scheme Variable} gdm-service-type
21028 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
21029 Desktop Manager} (GDM), a program that manages graphical display servers and
21030 handles graphical user logins. Its value must be a @code{gdm-configuration}
21033 @cindex session types
21034 GDM looks for @dfn{session types} described by the @file{.desktop} files in
21035 @file{/run/current-system/profile/share/xsessions} (for X11 sessions) and
21036 @file{/run/current-system/profile/share/wayland-sessions} (for Wayland
21037 sessions) and allows users to choose a session from the log-in screen.
21038 Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
21039 @file{.desktop} files; adding them to the system-wide set of packages
21040 automatically makes them available at the log-in screen.
21042 In addition, @file{~/.xsession} files are honored. When available,
21043 @file{~/.xsession} must be an executable that starts a window manager
21044 and/or other X clients.
21047 @deftp {Data Type} gdm-configuration
21049 @item @code{auto-login?} (default: @code{#f})
21050 @itemx @code{default-user} (default: @code{#f})
21051 When @code{auto-login?} is false, GDM presents a log-in screen.
21053 When @code{auto-login?} is true, GDM logs in directly as
21054 @code{default-user}.
21056 @item @code{debug?} (default: @code{#f})
21057 When true, GDM writes debug messages to its log.
21059 @item @code{gnome-shell-assets} (default: ...)
21060 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
21062 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
21063 Configuration of the Xorg graphical server.
21065 @item @code{x-session} (default: @code{(xinitrc)})
21066 Script to run before starting a X session.
21068 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
21069 File name of the @code{dbus-daemon} executable.
21071 @item @code{gdm} (default: @code{gdm})
21072 The GDM package to use.
21074 @item @code{wayland?} (default: @code{#f})
21075 When true, enables Wayland in GDM, necessary to use Wayland sessions.
21077 @item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
21078 The Wayland session wrapper to use, needed to setup the
21083 @defvr {Scheme Variable} slim-service-type
21084 This is the type for the SLiM graphical login manager for X11.
21086 Like GDM, SLiM looks for session types described by @file{.desktop} files and
21087 allows users to choose a session from the log-in screen using @kbd{F1}. It
21088 also honors @file{~/.xsession} files.
21090 Unlike GDM, SLiM does not spawn the user session on a different VT after
21091 logging in, which means that you can only start one graphical session. If you
21092 want to be able to run multiple graphical sessions at the same time you have
21093 to add multiple SLiM services to your system services. The following example
21094 shows how to replace the default GDM service with two SLiM services on tty7
21098 (use-modules (gnu services)
21099 (gnu services desktop)
21100 (gnu services xorg))
21104 (services (cons* (service slim-service-type (slim-configuration
21107 (service slim-service-type (slim-configuration
21110 (modify-services %desktop-services
21111 (delete gdm-service-type)))))
21116 @deftp {Data Type} slim-configuration
21117 Data type representing the configuration of @code{slim-service-type}.
21120 @item @code{allow-empty-passwords?} (default: @code{#t})
21121 Whether to allow logins with empty passwords.
21123 @item @code{gnupg?} (default: @code{#f})
21124 If enabled, @code{pam-gnupg} will attempt to automatically unlock the
21125 user's GPG keys with the login password via @code{gpg-agent}. The
21126 keygrips of all keys to be unlocked should be written to
21127 @file{~/.pam-gnupg}, and can be queried with @code{gpg -K
21128 --with-keygrip}. Presetting passphrases must be enabled by adding
21129 @code{allow-preset-passphrase} in @file{~/.gnupg/gpg-agent.conf}.
21131 @item @code{auto-login?} (default: @code{#f})
21132 @itemx @code{default-user} (default: @code{""})
21133 When @code{auto-login?} is false, SLiM presents a log-in screen.
21135 When @code{auto-login?} is true, SLiM logs in directly as
21136 @code{default-user}.
21138 @item @code{theme} (default: @code{%default-slim-theme})
21139 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
21140 The graphical theme to use and its name.
21142 @item @code{auto-login-session} (default: @code{#f})
21143 If true, this must be the name of the executable to start as the default
21144 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
21146 If false, a session described by one of the available @file{.desktop}
21147 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
21151 You must install at least one window manager in the system profile or in
21152 your user profile. Failing to do that, if @code{auto-login-session} is
21153 false, you will be unable to log in.
21156 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21157 Configuration of the Xorg graphical server.
21159 @item @code{display} (default @code{":0"})
21160 The display on which to start the Xorg graphical server.
21162 @item @code{vt} (default @code{"vt7"})
21163 The VT on which to start the Xorg graphical server.
21165 @item @code{xauth} (default: @code{xauth})
21166 The XAuth package to use.
21168 @item @code{shepherd} (default: @code{shepherd})
21169 The Shepherd package used when invoking @command{halt} and
21172 @item @code{sessreg} (default: @code{sessreg})
21173 The sessreg package used in order to register the session.
21175 @item @code{slim} (default: @code{slim})
21176 The SLiM package to use.
21180 @defvr {Scheme Variable} %default-theme
21181 @defvrx {Scheme Variable} %default-theme-name
21182 The default SLiM theme and its name.
21186 @cindex login manager
21188 @defvr {Scheme Variable} sddm-service-type
21189 This is the type of the service to run the
21190 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
21191 must be a @code{sddm-configuration} record (see below).
21193 Here's an example use:
21196 (service sddm-service-type
21197 (sddm-configuration
21198 (auto-login-user "alice")
21199 (auto-login-session "xfce.desktop")))
21203 @deftp {Data Type} sddm-configuration
21204 This data type represents the configuration of the SDDM login manager.
21205 The available fields are:
21208 @item @code{sddm} (default: @code{sddm})
21209 The SDDM package to use.
21211 @item @code{display-server} (default: "x11")
21212 Select display server to use for the greeter. Valid values are
21213 @samp{"x11"} or @samp{"wayland"}.
21215 @item @code{numlock} (default: "on")
21216 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
21218 @item @code{halt-command} (default @code{#~(string-append #$shepherd "/sbin/halt")})
21219 Command to run when halting.
21221 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
21222 Command to run when rebooting.
21224 @item @code{theme} (default "maldives")
21225 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
21226 @samp{"maldives"} or @samp{"maya"}.
21228 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
21229 Directory to look for themes.
21231 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
21232 Directory to look for faces.
21234 @item @code{default-path} (default "/run/current-system/profile/bin")
21235 Default PATH to use.
21237 @item @code{minimum-uid} (default: 1000)
21238 Minimum UID displayed in SDDM and allowed for log-in.
21240 @item @code{maximum-uid} (default: 2000)
21241 Maximum UID to display in SDDM.
21243 @item @code{remember-last-user?} (default #t)
21244 Remember last user.
21246 @item @code{remember-last-session?} (default #t)
21247 Remember last session.
21249 @item @code{hide-users} (default "")
21250 Usernames to hide from SDDM greeter.
21252 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
21253 Users with shells listed will be hidden from the SDDM greeter.
21255 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
21256 Script to run before starting a wayland session.
21258 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
21259 Directory to look for desktop files starting wayland sessions.
21261 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21262 Configuration of the Xorg graphical server.
21264 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
21267 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
21270 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
21271 Script to run after starting xorg-server.
21273 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
21274 Script to run before stopping xorg-server.
21276 @item @code{xsession-command} (default: @code{xinitrc})
21277 Script to run before starting a X session.
21279 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
21280 Directory to look for desktop files starting X sessions.
21282 @item @code{minimum-vt} (default: 7)
21285 @item @code{auto-login-user} (default "")
21286 User account that will be automatically logged in.
21287 Setting this to the empty string disables auto-login.
21289 @item @code{auto-login-session} (default "")
21290 The @file{.desktop} file name to use as the auto-login session, or the empty string.
21292 @item @code{relogin?} (default #f)
21293 Relogin after logout.
21298 @cindex lightdm, graphical login manager
21299 @cindex display manager, lightdm
21300 @defvr {Scheme Variable} lightdm-service-type
21301 This is the type of the service to run the
21302 @url{https://github.com/canonical/lightdm,LightDM display manager}. Its
21303 value must be a @code{lightdm-configuration} record, which is documented
21304 below. Among its distinguishing features are TigerVNC integration for
21305 easily remoting your desktop as well as support for the XDMCP protocol,
21306 which can be used by remote clients to start a session from the login
21309 In its most basic form, it can be used simply as:
21312 (service lightdm-service-type)
21315 A more elaborate example making use of the VNC capabilities and enabling
21316 more features and verbose logs could look like:
21319 (service lightdm-service-type
21320 (lightdm-configuration
21321 (allow-empty-passwords? #t)
21324 (vnc-server-command
21325 (file-append tigervnc-server "/bin/Xvnc"
21326 " -SecurityTypes None"))
21328 (list (lightdm-seat-configuration
21330 (user-session "ratpoison"))))))
21334 @c The LightDM service documentation can be auto-generated via the
21335 @c 'generate-doc' procedure at the bottom of the (gnu services lightdm)
21337 @c %start of fragment
21338 @deftp {Data Type} lightdm-configuration
21339 Available @code{lightdm-configuration} fields are:
21342 @item @code{lightdm} (default: @code{lightdm}) (type: file-like)
21343 The lightdm package to use.
21345 @item @code{allow-empty-passwords?} (default: @code{#f}) (type: boolean)
21346 Whether users not having a password set can login.
21348 @item @code{debug?} (default: @code{#f}) (type: boolean)
21349 Enable verbose output.
21351 @item @code{xorg-configuration} (type: xorg-configuration)
21352 The default Xorg server configuration to use to generate the Xorg server
21353 start script. It can be refined per seat via the @code{xserver-command}
21354 of the @code{<lightdm-seat-configuration>} record, if desired.
21356 @item @code{greeters} (type: list-of-greeter-configurations)
21357 The LightDM greeter configurations specifying the greeters to use.
21359 @item @code{seats} (type: list-of-seat-configurations)
21360 The seat configurations to use. A LightDM seat is akin to a user.
21362 @item @code{xdmcp?} (default: @code{#f}) (type: boolean)
21363 Whether a XDMCP server should listen on port UDP 177.
21365 @item @code{xdmcp-listen-address} (type: maybe-string)
21366 The host or IP address the XDMCP server listens for incoming
21367 connections. When unspecified, listen on for any hosts/IP addresses.
21369 @item @code{vnc-server?} (default: @code{#f}) (type: boolean)
21370 Whether a VNC server is started.
21372 @item @code{vnc-server-command} (type: file-like)
21373 The Xvnc command to use for the VNC server, it's possible to provide
21374 extra options not otherwise exposed along the command, for example to
21378 (vnc-server-command (file-append tigervnc-server "/bin/Xvnc"
21379 " -SecurityTypes None" ))
21382 Or to set a PasswordFile for the classic (unsecure) VncAuth
21386 (vnc-server-command (file-append tigervnc-server "/bin/Xvnc"
21387 " -PasswordFile /var/lib/lightdm/.vnc/passwd"))
21390 The password file should be manually created using the
21391 @command{vncpasswd} command. Note that LightDM will create new sessions
21392 for VNC users, which means they need to authenticate in the same way as
21395 @item @code{vnc-server-listen-address} (type: maybe-string)
21396 The host or IP address the VNC server listens for incoming connections.
21397 When unspecified, listen for any hosts/IP addresses.
21399 @item @code{vnc-server-port} (default: @code{5900}) (type: number)
21400 The TCP port the VNC server should listen to.
21402 @item @code{extra-config} (default: @code{()}) (type: list-of-strings)
21403 Extra configuration values to append to the LightDM configuration file.
21409 @c %end of fragment
21410 @c %start of fragment
21412 @deftp {Data Type} lightdm-gtk-greeter-configuration
21413 Available @code{lightdm-gtk-greeter-configuration} fields are:
21416 @item @code{lightdm-gtk-greeter} (default: @code{lightdm-gtk-greeter}) (type: file-like)
21417 The lightdm-gtk-greeter package to use.
21419 @item @code{assets} @
21420 (default: @code{(adwaita-icon-theme gnome-themes-extrahicolor-icon-theme)}) @
21421 (type: list-of-file-likes)
21422 The list of packages complementing the greeter, such as package
21423 providing icon themes.
21425 @item @code{theme-name} (default: @code{"Adwaita"}) (type: string)
21426 The name of the theme to use.
21428 @item @code{icon-theme-name} (default: @code{"Adwaita"}) (type: string)
21429 The name of the icon theme to use.
21431 @item @code{cursor-theme-name} (default: @code{"Adwaita"}) (type: string)
21432 The name of the cursor theme to use.
21434 @item @code{cursor-theme-size} (default: @code{16}) (type: number)
21435 The size to use for the the cursor theme.
21437 @item @code{allow-debugging?} (type: maybe-boolean)
21438 Set to #t to enable debug log level.
21440 @item @code{background} (type: file-like)
21441 The background image to use.
21443 @item @code{at-spi-enabled?} (default: @code{#f}) (type: boolean)
21444 Enable accessibility support through the Assistive Technology Service
21445 Provider Interface (AT-SPI).
21447 @item @code{a11y-states} @
21448 (default: @code{(contrast font keyboard reader)}) (type: list-of-a11y-states)
21449 The accessibility features to enable, given as list of symbols.
21451 @item @code{reader} (type: maybe-file-like)
21452 The command to use to launch a screen reader.
21454 @item @code{extra-config} (default: @code{()}) (type: list-of-strings)
21455 Extra configuration values to append to the LightDM GTK Greeter
21456 configuration file.
21461 @c %end of fragment
21462 @c %start of fragment
21464 @deftp {Data Type} lightdm-seat-configuration
21465 Available @code{lightdm-seat-configuration} fields are:
21468 @item @code{name} (type: seat-name)
21469 The name of the seat. An asterisk (*) can be used in the name to apply
21470 the seat configuration to all the seat names it matches.
21472 @item @code{user-session} (type: maybe-string)
21473 The session to use by default. The session name must be provided as a
21474 lowercase string, such as @code{"gnome"}, @code{"ratpoison"}, etc.
21476 @item @code{type} (default: @code{local}) (type: seat-type)
21477 The type of the seat, either the @code{local} or @code{xremote} symbol.
21479 @item @code{autologin-user} (type: maybe-string)
21480 The username to automatically log in with by default.
21482 @item @code{greeter-session} @
21483 (default: @code{lightdm-gtk-greeter}) (type: greeter-session)
21484 The greeter session to use, specified as a symbol. Currently, only
21485 @code{lightdm-gtk-greeter} is supported.
21487 @item @code{xserver-command} (type: maybe-file-like)
21488 The Xorg server command to run.
21490 @item @code{session-wrapper} (type: file-like)
21491 The xinitrc session wrapper to use.
21493 @item @code{extra-config} (default: @code{()}) (type: list-of-strings)
21494 Extra configuration values to append to the seat configuration section.
21498 @c %end of fragment
21501 @cindex Xorg, configuration
21502 @deftp {Data Type} xorg-configuration
21503 This data type represents the configuration of the Xorg graphical display
21504 server. Note that there is no Xorg service; instead, the X server is started
21505 by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
21506 of these display managers aggregates an @code{xorg-configuration} record.
21509 @item @code{modules} (default: @code{%default-xorg-modules})
21510 This is a list of @dfn{module packages} loaded by the Xorg
21511 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
21513 @item @code{fonts} (default: @code{%default-xorg-fonts})
21514 This is a list of font directories to add to the server's @dfn{font path}.
21516 @item @code{drivers} (default: @code{'()})
21517 This must be either the empty list, in which case Xorg chooses a graphics
21518 driver automatically, or a list of driver names that will be tried in this
21519 order---e.g., @code{("modesetting" "vesa")}.
21521 @item @code{resolutions} (default: @code{'()})
21522 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
21523 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
21526 @cindex keyboard layout, for Xorg
21527 @cindex keymap, for Xorg
21528 @item @code{keyboard-layout} (default: @code{#f})
21529 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
21530 English (``qwerty'') for a 105-key PC keyboard.
21532 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
21533 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
21534 information on how to specify the keyboard layout.
21536 @item @code{extra-config} (default: @code{'()})
21537 This is a list of strings or objects appended to the configuration file. It
21538 is used to pass extra text to be added verbatim to the configuration file.
21540 @item @code{server} (default: @code{xorg-server})
21541 This is the package providing the Xorg server.
21543 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
21544 This is the list of command-line arguments to pass to the X server. The
21545 default is @code{-nolisten tcp}.
21549 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
21550 [@var{login-manager-service-type}]
21551 Tell the log-in manager (of type @var{login-manager-service-type}) to use
21552 @var{config}, an @code{<xorg-configuration>} record.
21554 Since the Xorg configuration is embedded in the log-in manager's
21555 configuration---e.g., @code{gdm-configuration}---this procedure provides a
21556 shorthand to set the Xorg configuration.
21559 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
21560 Return a @code{startx} script in which the modules, fonts, etc. specified
21561 in @var{config}, are available. The result should be used in place of
21564 Usually the X server is started by a login manager.
21568 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
21569 Add @var{package}, a package for a screen locker or screen saver whose
21570 command is @var{program}, to the set of setuid programs and add a PAM entry
21571 for it. For example:
21574 (screen-locker-service xlockmore "xlock")
21577 makes the good ol' XlockMore usable.
21581 @node Printing Services
21582 @subsection Printing Services
21584 @cindex printer support with CUPS
21585 The @code{(gnu services cups)} module provides a Guix service definition
21586 for the CUPS printing service. To add printer support to a Guix
21587 system, add a @code{cups-service} to the operating system definition:
21589 @deffn {Scheme Variable} cups-service-type
21590 The service type for the CUPS print server. Its value should be a valid
21591 CUPS configuration (see below). To use the default settings, simply
21594 (service cups-service-type)
21598 The CUPS configuration controls the basic things about your CUPS
21599 installation: what interfaces it listens on, what to do if a print job
21600 fails, how much logging to do, and so on. To actually add a printer,
21601 you have to visit the @url{http://localhost:631} URL, or use a tool such
21602 as GNOME's printer configuration services. By default, configuring a
21603 CUPS service will generate a self-signed certificate if needed, for
21604 secure connections to the print server.
21606 Suppose you want to enable the Web interface of CUPS and also add
21607 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
21608 package and for HP printers @i{via} the @code{hplip-minimal} package.
21609 You can do that directly, like this (you need to use the
21610 @code{(gnu packages cups)} module):
21613 (service cups-service-type
21614 (cups-configuration
21615 (web-interface? #t)
21617 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
21621 If you wish to use the Qt5 based GUI which comes with the hplip
21622 package then it is suggested that you install the @code{hplip} package,
21623 either in your OS configuration file or as your user.
21626 The available configuration parameters follow. Each parameter
21627 definition is preceded by its type; for example, @samp{string-list foo}
21628 indicates that the @code{foo} parameter should be specified as a list of
21629 strings. There is also a way to specify the configuration as a string,
21630 if you have an old @code{cupsd.conf} file that you want to port over
21631 from some other system; see the end for more details.
21633 @c The following documentation was initially generated by
21634 @c (generate-documentation) in (gnu services cups). Manually maintained
21635 @c documentation is better, so we shouldn't hesitate to edit below as
21636 @c needed. However if the change you want to make to this documentation
21637 @c can be done in an automated way, it's probably easier to change
21638 @c (generate-documentation) than to make it below and have to deal with
21639 @c the churn as CUPS updates.
21642 Available @code{cups-configuration} fields are:
21644 @deftypevr {@code{cups-configuration} parameter} package cups
21648 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
21649 Drivers and other extensions to the CUPS package.
21652 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
21653 Configuration of where to write logs, what directories to use for print
21654 spools, and related privileged configuration parameters.
21656 Available @code{files-configuration} fields are:
21658 @deftypevr {@code{files-configuration} parameter} log-location access-log
21659 Defines the access log filename. Specifying a blank filename disables
21660 access log generation. The value @code{stderr} causes log entries to be
21661 sent to the standard error file when the scheduler is running in the
21662 foreground, or to the system log daemon when run in the background. The
21663 value @code{syslog} causes log entries to be sent to the system log
21664 daemon. The server name may be included in filenames using the string
21665 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
21667 Defaults to @samp{"/var/log/cups/access_log"}.
21670 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
21671 Where CUPS should cache data.
21673 Defaults to @samp{"/var/cache/cups"}.
21676 @deftypevr {@code{files-configuration} parameter} string config-file-perm
21677 Specifies the permissions for all configuration files that the scheduler
21680 Note that the permissions for the printers.conf file are currently
21681 masked to only allow access from the scheduler user (typically root).
21682 This is done because printer device URIs sometimes contain sensitive
21683 authentication information that should not be generally known on the
21684 system. There is no way to disable this security feature.
21686 Defaults to @samp{"0640"}.
21689 @deftypevr {@code{files-configuration} parameter} log-location error-log
21690 Defines the error log filename. Specifying a blank filename disables
21691 error log generation. The value @code{stderr} causes log entries to be
21692 sent to the standard error file when the scheduler is running in the
21693 foreground, or to the system log daemon when run in the background. The
21694 value @code{syslog} causes log entries to be sent to the system log
21695 daemon. The server name may be included in filenames using the string
21696 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
21698 Defaults to @samp{"/var/log/cups/error_log"}.
21701 @deftypevr {@code{files-configuration} parameter} string fatal-errors
21702 Specifies which errors are fatal, causing the scheduler to exit. The
21707 No errors are fatal.
21710 All of the errors below are fatal.
21713 Browsing initialization errors are fatal, for example failed connections
21714 to the DNS-SD daemon.
21717 Configuration file syntax errors are fatal.
21720 Listen or Port errors are fatal, except for IPv6 failures on the
21721 loopback or @code{any} addresses.
21724 Log file creation or write errors are fatal.
21727 Bad startup file permissions are fatal, for example shared TLS
21728 certificate and key files with world-read permissions.
21731 Defaults to @samp{"all -browse"}.
21734 @deftypevr {@code{files-configuration} parameter} boolean file-device?
21735 Specifies whether the file pseudo-device can be used for new printer
21736 queues. The URI @uref{file:///dev/null} is always allowed.
21738 Defaults to @samp{#f}.
21741 @deftypevr {@code{files-configuration} parameter} string group
21742 Specifies the group name or ID that will be used when executing external
21745 Defaults to @samp{"lp"}.
21748 @deftypevr {@code{files-configuration} parameter} string log-file-group
21749 Specifies the group name or ID that will be used for log files.
21751 Defaults to @samp{"lpadmin"}.
21754 @deftypevr {@code{files-configuration} parameter} string log-file-perm
21755 Specifies the permissions for all log files that the scheduler writes.
21757 Defaults to @samp{"0644"}.
21760 @deftypevr {@code{files-configuration} parameter} log-location page-log
21761 Defines the page log filename. Specifying a blank filename disables
21762 page log generation. The value @code{stderr} causes log entries to be
21763 sent to the standard error file when the scheduler is running in the
21764 foreground, or to the system log daemon when run in the background. The
21765 value @code{syslog} causes log entries to be sent to the system log
21766 daemon. The server name may be included in filenames using the string
21767 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
21769 Defaults to @samp{"/var/log/cups/page_log"}.
21772 @deftypevr {@code{files-configuration} parameter} string remote-root
21773 Specifies the username that is associated with unauthenticated accesses
21774 by clients claiming to be the root user. The default is @code{remroot}.
21776 Defaults to @samp{"remroot"}.
21779 @deftypevr {@code{files-configuration} parameter} file-name request-root
21780 Specifies the directory that contains print jobs and other HTTP request
21783 Defaults to @samp{"/var/spool/cups"}.
21786 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
21787 Specifies the level of security sandboxing that is applied to print
21788 filters, backends, and other child processes of the scheduler; either
21789 @code{relaxed} or @code{strict}. This directive is currently only
21790 used/supported on macOS.
21792 Defaults to @samp{strict}.
21795 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
21796 Specifies the location of TLS certificates and private keys. CUPS will
21797 look for public and private keys in this directory: @file{.crt} files
21798 for PEM-encoded certificates and corresponding @file{.key} files for
21799 PEM-encoded private keys.
21801 Defaults to @samp{"/etc/cups/ssl"}.
21804 @deftypevr {@code{files-configuration} parameter} file-name server-root
21805 Specifies the directory containing the server configuration files.
21807 Defaults to @samp{"/etc/cups"}.
21810 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
21811 Specifies whether the scheduler calls fsync(2) after writing
21812 configuration or state files.
21814 Defaults to @samp{#f}.
21817 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
21818 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
21821 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
21822 Specifies the directory where temporary files are stored.
21824 Defaults to @samp{"/var/spool/cups/tmp"}.
21827 @deftypevr {@code{files-configuration} parameter} string user
21828 Specifies the user name or ID that is used when running external
21831 Defaults to @samp{"lp"}.
21834 @deftypevr {@code{files-configuration} parameter} string set-env
21835 Set the specified environment variable to be passed to child processes.
21837 Defaults to @samp{"variable value"}.
21841 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
21842 Specifies the logging level for the AccessLog file. The @code{config}
21843 level logs when printers and classes are added, deleted, or modified and
21844 when configuration files are accessed or updated. The @code{actions}
21845 level logs when print jobs are submitted, held, released, modified, or
21846 canceled, and any of the conditions for @code{config}. The @code{all}
21847 level logs all requests.
21849 Defaults to @samp{actions}.
21852 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
21853 Specifies whether to purge job history data automatically when it is no
21854 longer required for quotas.
21856 Defaults to @samp{#f}.
21859 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
21860 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
21861 For example, @samp{"_cups" "_print"} will tell network clients that both
21862 CUPS sharing and IPP Everywhere are supported.
21864 Defaults to @samp{"_cups"}.
21867 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
21868 Specifies which protocols to use for local printer sharing.
21870 Defaults to @samp{dnssd}.
21873 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
21874 Specifies whether the CUPS web interface is advertised.
21876 Defaults to @samp{#f}.
21879 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
21880 Specifies whether shared printers are advertised.
21882 Defaults to @samp{#f}.
21885 @deftypevr {@code{cups-configuration} parameter} string classification
21886 Specifies the security classification of the server. Any valid banner
21887 name can be used, including @samp{"classified"}, @samp{"confidential"},
21888 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
21889 banner can be omitted to disable secure printing functions.
21891 Defaults to @samp{""}.
21894 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
21895 Specifies whether users may override the classification (cover page) of
21896 individual print jobs using the @code{job-sheets} option.
21898 Defaults to @samp{#f}.
21901 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
21902 Specifies the default type of authentication to use.
21904 Defaults to @samp{Basic}.
21907 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
21908 Specifies whether encryption will be used for authenticated requests.
21910 Defaults to @samp{Required}.
21913 @deftypevr {@code{cups-configuration} parameter} string default-language
21914 Specifies the default language to use for text and web content.
21916 Defaults to @samp{"en"}.
21919 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
21920 Specifies the default paper size for new print queues. @samp{"Auto"}
21921 uses a locale-specific default, while @samp{"None"} specifies there is
21922 no default paper size. Specific size names are typically
21923 @samp{"Letter"} or @samp{"A4"}.
21925 Defaults to @samp{"Auto"}.
21928 @deftypevr {@code{cups-configuration} parameter} string default-policy
21929 Specifies the default access policy to use.
21931 Defaults to @samp{"default"}.
21934 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
21935 Specifies whether local printers are shared by default.
21937 Defaults to @samp{#t}.
21940 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
21941 Specifies the delay for updating of configuration and state files, in
21942 seconds. A value of 0 causes the update to happen as soon as possible,
21943 typically within a few milliseconds.
21945 Defaults to @samp{30}.
21948 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
21949 Specifies what to do when an error occurs. Possible values are
21950 @code{abort-job}, which will discard the failed print job;
21951 @code{retry-job}, which will retry the job at a later time;
21952 @code{retry-current-job}, which retries the failed job immediately; and
21953 @code{stop-printer}, which stops the printer.
21955 Defaults to @samp{stop-printer}.
21958 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
21959 Specifies the maximum cost of filters that are run concurrently, which
21960 can be used to minimize disk, memory, and CPU resource problems. A
21961 limit of 0 disables filter limiting. An average print to a
21962 non-PostScript printer needs a filter limit of about 200. A PostScript
21963 printer needs about half that (100). Setting the limit below these
21964 thresholds will effectively limit the scheduler to printing a single job
21967 Defaults to @samp{0}.
21970 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
21971 Specifies the scheduling priority of filters that are run to print a
21972 job. The nice value ranges from 0, the highest priority, to 19, the
21975 Defaults to @samp{0}.
21978 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
21979 Specifies whether to do reverse lookups on connecting clients. The
21980 @code{double} setting causes @code{cupsd} to verify that the hostname
21981 resolved from the address matches one of the addresses returned for that
21982 hostname. Double lookups also prevent clients with unregistered
21983 addresses from connecting to your server. Only set this option to
21984 @code{#t} or @code{double} if absolutely required.
21986 Defaults to @samp{#f}.
21989 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
21990 Specifies the number of seconds to wait before killing the filters and
21991 backend associated with a canceled or held job.
21993 Defaults to @samp{30}.
21996 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
21997 Specifies the interval between retries of jobs in seconds. This is
21998 typically used for fax queues but can also be used with normal print
21999 queues whose error policy is @code{retry-job} or
22000 @code{retry-current-job}.
22002 Defaults to @samp{30}.
22005 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
22006 Specifies the number of retries that are done for jobs. This is
22007 typically used for fax queues but can also be used with normal print
22008 queues whose error policy is @code{retry-job} or
22009 @code{retry-current-job}.
22011 Defaults to @samp{5}.
22014 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
22015 Specifies whether to support HTTP keep-alive connections.
22017 Defaults to @samp{#t}.
22020 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
22021 Specifies the maximum size of print files, IPP requests, and HTML form
22022 data. A limit of 0 disables the limit check.
22024 Defaults to @samp{0}.
22027 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
22028 Listens on the specified interfaces for connections. Valid values are
22029 of the form @var{address}:@var{port}, where @var{address} is either an
22030 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
22031 indicate all addresses. Values can also be file names of local UNIX
22032 domain sockets. The Listen directive is similar to the Port directive
22033 but allows you to restrict access to specific interfaces or networks.
22036 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
22037 Specifies the number of pending connections that will be allowed. This
22038 normally only affects very busy servers that have reached the MaxClients
22039 limit, but can also be triggered by large numbers of simultaneous
22040 connections. When the limit is reached, the operating system will
22041 refuse additional connections until the scheduler can accept the pending
22044 Defaults to @samp{128}.
22047 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
22048 Specifies a set of additional access controls.
22050 Available @code{location-access-controls} fields are:
22052 @deftypevr {@code{location-access-controls} parameter} file-name path
22053 Specifies the URI path to which the access control applies.
22056 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
22057 Access controls for all access to this path, in the same format as the
22058 @code{access-controls} of @code{operation-access-control}.
22060 Defaults to @samp{()}.
22063 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
22064 Access controls for method-specific access to this path.
22066 Defaults to @samp{()}.
22068 Available @code{method-access-controls} fields are:
22070 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
22071 If @code{#t}, apply access controls to all methods except the listed
22072 methods. Otherwise apply to only the listed methods.
22074 Defaults to @samp{#f}.
22077 @deftypevr {@code{method-access-controls} parameter} method-list methods
22078 Methods to which this access control applies.
22080 Defaults to @samp{()}.
22083 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
22084 Access control directives, as a list of strings. Each string should be
22085 one directive, such as @samp{"Order allow,deny"}.
22087 Defaults to @samp{()}.
22092 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
22093 Specifies the number of debugging messages that are retained for logging
22094 if an error occurs in a print job. Debug messages are logged regardless
22095 of the LogLevel setting.
22097 Defaults to @samp{100}.
22100 @deftypevr {@code{cups-configuration} parameter} log-level log-level
22101 Specifies the level of logging for the ErrorLog file. The value
22102 @code{none} stops all logging while @code{debug2} logs everything.
22104 Defaults to @samp{info}.
22107 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
22108 Specifies the format of the date and time in the log files. The value
22109 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
22111 Defaults to @samp{standard}.
22114 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
22115 Specifies the maximum number of simultaneous clients that are allowed by
22118 Defaults to @samp{100}.
22121 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
22122 Specifies the maximum number of simultaneous clients that are allowed
22123 from a single address.
22125 Defaults to @samp{100}.
22128 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
22129 Specifies the maximum number of copies that a user can print of each
22132 Defaults to @samp{9999}.
22135 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
22136 Specifies the maximum time a job may remain in the @code{indefinite}
22137 hold state before it is canceled. A value of 0 disables cancellation of
22140 Defaults to @samp{0}.
22143 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
22144 Specifies the maximum number of simultaneous jobs that are allowed. Set
22145 to 0 to allow an unlimited number of jobs.
22147 Defaults to @samp{500}.
22150 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
22151 Specifies the maximum number of simultaneous jobs that are allowed per
22152 printer. A value of 0 allows up to MaxJobs jobs per printer.
22154 Defaults to @samp{0}.
22157 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
22158 Specifies the maximum number of simultaneous jobs that are allowed per
22159 user. A value of 0 allows up to MaxJobs jobs per user.
22161 Defaults to @samp{0}.
22164 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
22165 Specifies the maximum time a job may take to print before it is
22166 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
22168 Defaults to @samp{10800}.
22171 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
22172 Specifies the maximum size of the log files before they are rotated, in
22173 bytes. The value 0 disables log rotation.
22175 Defaults to @samp{1048576}.
22178 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
22179 Specifies the maximum amount of time to allow between files in a
22180 multiple file print job, in seconds.
22182 Defaults to @samp{900}.
22185 @deftypevr {@code{cups-configuration} parameter} string page-log-format
22186 Specifies the format of PageLog lines. Sequences beginning with percent
22187 (@samp{%}) characters are replaced with the corresponding information,
22188 while all other characters are copied literally. The following percent
22189 sequences are recognized:
22193 insert a single percent character
22196 insert the value of the specified IPP attribute
22199 insert the number of copies for the current page
22202 insert the current page number
22205 insert the current date and time in common log format
22211 insert the printer name
22214 insert the username
22217 A value of the empty string disables page logging. The string @code{%p
22218 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
22219 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
22222 Defaults to @samp{""}.
22225 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
22226 Passes the specified environment variable(s) to child processes; a list
22229 Defaults to @samp{()}.
22232 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
22233 Specifies named access control policies.
22235 Available @code{policy-configuration} fields are:
22237 @deftypevr {@code{policy-configuration} parameter} string name
22238 Name of the policy.
22241 @deftypevr {@code{policy-configuration} parameter} string job-private-access
22242 Specifies an access list for a job's private values. @code{@@ACL} maps
22243 to the printer's requesting-user-name-allowed or
22244 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
22245 owner. @code{@@SYSTEM} maps to the groups listed for the
22246 @code{system-group} field of the @code{files-configuration},
22247 which is reified into the @code{cups-files.conf(5)} file. Other
22248 possible elements of the access list include specific user names, and
22249 @code{@@@var{group}} to indicate members of a specific group. The
22250 access list may also be simply @code{all} or @code{default}.
22252 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22255 @deftypevr {@code{policy-configuration} parameter} string job-private-values
22256 Specifies the list of job values to make private, or @code{all},
22257 @code{default}, or @code{none}.
22259 Defaults to @samp{"job-name job-originating-host-name
22260 job-originating-user-name phone"}.
22263 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
22264 Specifies an access list for a subscription's private values.
22265 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
22266 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
22267 owner. @code{@@SYSTEM} maps to the groups listed for the
22268 @code{system-group} field of the @code{files-configuration},
22269 which is reified into the @code{cups-files.conf(5)} file. Other
22270 possible elements of the access list include specific user names, and
22271 @code{@@@var{group}} to indicate members of a specific group. The
22272 access list may also be simply @code{all} or @code{default}.
22274 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22277 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
22278 Specifies the list of job values to make private, or @code{all},
22279 @code{default}, or @code{none}.
22281 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
22282 notify-subscriber-user-name notify-user-data"}.
22285 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
22286 Access control by IPP operation.
22288 Defaults to @samp{()}.
22292 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
22293 Specifies whether job files (documents) are preserved after a job is
22294 printed. If a numeric value is specified, job files are preserved for
22295 the indicated number of seconds after printing. Otherwise a boolean
22296 value applies indefinitely.
22298 Defaults to @samp{86400}.
22301 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
22302 Specifies whether the job history is preserved after a job is printed.
22303 If a numeric value is specified, the job history is preserved for the
22304 indicated number of seconds after printing. If @code{#t}, the job
22305 history is preserved until the MaxJobs limit is reached.
22307 Defaults to @samp{#t}.
22310 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
22311 Specifies the amount of time to wait for job completion before
22312 restarting the scheduler.
22314 Defaults to @samp{30}.
22317 @deftypevr {@code{cups-configuration} parameter} string rip-cache
22318 Specifies the maximum amount of memory to use when converting documents
22319 into bitmaps for a printer.
22321 Defaults to @samp{"128m"}.
22324 @deftypevr {@code{cups-configuration} parameter} string server-admin
22325 Specifies the email address of the server administrator.
22327 Defaults to @samp{"root@@localhost.localdomain"}.
22330 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
22331 The ServerAlias directive is used for HTTP Host header validation when
22332 clients connect to the scheduler from external interfaces. Using the
22333 special name @code{*} can expose your system to known browser-based DNS
22334 rebinding attacks, even when accessing sites through a firewall. If the
22335 auto-discovery of alternate names does not work, we recommend listing
22336 each alternate name with a ServerAlias directive instead of using
22339 Defaults to @samp{*}.
22342 @deftypevr {@code{cups-configuration} parameter} string server-name
22343 Specifies the fully-qualified host name of the server.
22345 Defaults to @samp{"localhost"}.
22348 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
22349 Specifies what information is included in the Server header of HTTP
22350 responses. @code{None} disables the Server header. @code{ProductOnly}
22351 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
22352 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
22353 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
22354 the output of the @code{uname} command. @code{Full} reports @code{CUPS
22355 2.0.0 (@var{uname}) IPP/2.0}.
22357 Defaults to @samp{Minimal}.
22360 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
22361 Listens on the specified interfaces for encrypted connections. Valid
22362 values are of the form @var{address}:@var{port}, where @var{address} is
22363 either an IPv6 address enclosed in brackets, an IPv4 address, or
22364 @code{*} to indicate all addresses.
22366 Defaults to @samp{()}.
22369 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
22370 Sets encryption options. By default, CUPS only supports encryption
22371 using TLS v1.0 or higher using known secure cipher suites. Security is
22372 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
22373 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
22374 suites, which are required for some older clients. The @code{AllowSSL3} option
22375 enables SSL v3.0, which is required for some older clients that do not support
22376 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
22377 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
22378 protocol version to TLS v1.1.
22380 Defaults to @samp{()}.
22383 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
22384 Specifies whether the scheduler requires clients to strictly adhere to
22385 the IPP specifications.
22387 Defaults to @samp{#f}.
22390 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
22391 Specifies the HTTP request timeout, in seconds.
22393 Defaults to @samp{900}.
22397 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
22398 Specifies whether the web interface is enabled.
22400 Defaults to @samp{#f}.
22403 At this point you're probably thinking ``oh dear, Guix manual, I like
22404 you but you can stop already with the configuration options''. Indeed.
22405 However, one more point: it could be that you have an existing
22406 @code{cupsd.conf} that you want to use. In that case, you can pass an
22407 @code{opaque-cups-configuration} as the configuration of a
22408 @code{cups-service-type}.
22410 Available @code{opaque-cups-configuration} fields are:
22412 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
22416 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
22417 The contents of the @code{cupsd.conf}, as a string.
22420 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
22421 The contents of the @code{cups-files.conf} file, as a string.
22424 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
22425 strings of the same name, you could instantiate a CUPS service like
22429 (service cups-service-type
22430 (opaque-cups-configuration
22431 (cupsd.conf cupsd.conf)
22432 (cups-files.conf cups-files.conf)))
22436 @node Desktop Services
22437 @subsection Desktop Services
22439 The @code{(gnu services desktop)} module provides services that are
22440 usually useful in the context of a ``desktop'' setup---that is, on a
22441 machine running a graphical display server, possibly with graphical user
22442 interfaces, etc. It also defines services that provide specific desktop
22443 environments like GNOME, Xfce or MATE.
22445 To simplify things, the module defines a variable containing the set of
22446 services that users typically expect on a machine with a graphical
22447 environment and networking:
22449 @defvr {Scheme Variable} %desktop-services
22450 This is a list of services that builds upon @code{%base-services} and
22451 adds or adjusts services for a typical ``desktop'' setup.
22453 In particular, it adds a graphical login manager (@pxref{X Window,
22454 @code{gdm-service-type}}), screen lockers, a network management tool
22455 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
22456 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
22457 energy and color management services, the @code{elogind} login and seat
22458 manager, the Polkit privilege service, the GeoClue location service, the
22459 AccountsService daemon that allows authorized users change system passwords,
22460 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
22461 name service switch service configured to be able to use @code{nss-mdns}
22462 (@pxref{Name Service Switch, mDNS}).
22465 The @code{%desktop-services} variable can be used as the @code{services}
22466 field of an @code{operating-system} declaration (@pxref{operating-system
22467 Reference, @code{services}}).
22469 Additionally, the @code{gnome-desktop-service-type},
22470 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
22471 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
22472 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
22473 ``add GNOME'' means that system-level services like the backlight adjustment
22474 helpers and the power management utilities are added to the system, extending
22475 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
22476 elevated privileges on a limited number of special-purpose system interfaces.
22477 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
22478 the GNOME metapackage to the system profile. Likewise, adding the Xfce
22479 service not only adds the @code{xfce} metapackage to the system profile, but
22480 it also gives the Thunar file manager the ability to open a ``root-mode'' file
22481 management window, if the user authenticates using the administrator's
22482 password via the standard polkit graphical interface. To ``add MATE'' means
22483 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
22484 to operate with elevated privileges on a limited number of special-purpose
22485 system interfaces. Additionally, adding a service of type
22486 @code{mate-desktop-service-type} adds the MATE metapackage to the system
22487 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
22488 appropriately, and several of Enlightenment's binaries are set as setuid,
22489 allowing Enlightenment's screen locker and other functionality to work as
22492 The desktop environments in Guix use the Xorg display server by
22493 default. If you'd like to use the newer display server protocol
22494 called Wayland, you need to enable Wayland support in GDM
22495 (@pxref{wayland-gdm}). Another solution is to use the
22496 @code{sddm-service} instead of GDM as the graphical login manager.
22497 You should then select the ``GNOME (Wayland)'' session in SDDM@.
22498 Alternatively you can also try starting GNOME on Wayland manually from a
22499 TTY with the command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
22500 gnome-session``. Currently only GNOME has support for Wayland.
22502 @defvr {Scheme Variable} gnome-desktop-service-type
22503 This is the type of the service that adds the @uref{https://www.gnome.org,
22504 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
22505 object (see below).
22507 This service adds the @code{gnome} package to the system profile, and extends
22508 polkit with the actions from @code{gnome-settings-daemon}.
22511 @deftp {Data Type} gnome-desktop-configuration
22512 Configuration record for the GNOME desktop environment.
22515 @item @code{gnome} (default: @code{gnome})
22516 The GNOME package to use.
22520 @defvr {Scheme Variable} xfce-desktop-service-type
22521 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
22522 desktop environment. Its value is an @code{xfce-desktop-configuration} object
22525 This service adds the @code{xfce} package to the system profile, and
22526 extends polkit with the ability for @code{thunar} to manipulate the file
22527 system as root from within a user session, after the user has authenticated
22528 with the administrator's password.
22530 Note that @code{xfce4-panel} and its plugin packages should be installed in
22531 the same profile to ensure compatibility. When using this service, you should
22532 add extra plugins (@code{xfce4-whiskermenu-plugin},
22533 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
22534 @code{operating-system}.
22537 @deftp {Data Type} xfce-desktop-configuration
22538 Configuration record for the Xfce desktop environment.
22541 @item @code{xfce} (default: @code{xfce})
22542 The Xfce package to use.
22546 @deffn {Scheme Variable} mate-desktop-service-type
22547 This is the type of the service that runs the @uref{https://mate-desktop.org/,
22548 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
22549 object (see below).
22551 This service adds the @code{mate} package to the system
22552 profile, and extends polkit with the actions from
22553 @code{mate-settings-daemon}.
22556 @deftp {Data Type} mate-desktop-configuration
22557 Configuration record for the MATE desktop environment.
22560 @item @code{mate} (default: @code{mate})
22561 The MATE package to use.
22565 @deffn {Scheme Variable} lxqt-desktop-service-type
22566 This is the type of the service that runs the @uref{https://lxqt-project.org,
22567 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
22568 object (see below).
22570 This service adds the @code{lxqt} package to the system
22574 @deftp {Data Type} lxqt-desktop-configuration
22575 Configuration record for the LXQt desktop environment.
22578 @item @code{lxqt} (default: @code{lxqt})
22579 The LXQT package to use.
22583 @deffn {Scheme Variable} enlightenment-desktop-service-type
22584 Return a service that adds the @code{enlightenment} package to the system
22585 profile, and extends dbus with actions from @code{efl}.
22588 @deftp {Data Type} enlightenment-desktop-service-configuration
22590 @item @code{enlightenment} (default: @code{enlightenment})
22591 The enlightenment package to use.
22595 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
22596 the default @code{%desktop-services} variable doesn't include any of
22597 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
22598 @code{%desktop-services} in the @code{services} field of your
22599 @code{operating-system}:
22602 (use-modules (gnu))
22603 (use-service-modules desktop)
22606 ;; cons* adds items to the list given as its last argument.
22607 (services (cons* (service gnome-desktop-service-type)
22608 (service xfce-desktop-service)
22609 %desktop-services))
22613 These desktop environments will then be available as options in the
22614 graphical login window.
22616 The actual service definitions included in @code{%desktop-services} and
22617 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
22618 are described below.
22620 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()] @
22622 Return a service that runs the ``system bus'', using @var{dbus}, with
22623 support for @var{services}. When @var{verbose?} is true, it causes the
22624 @samp{DBUS_VERBOSE} environment variable to be set to @samp{1}; a
22625 verbose-enabled D-Bus package such as @code{dbus-verbose} should be
22626 provided as @var{dbus} in this scenario. The verbose output is logged
22627 to @file{/var/log/dbus-daemon.log}.
22629 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
22630 facility. Its system bus is used to allow system services to communicate
22631 and to be notified of system-wide events.
22633 @var{services} must be a list of packages that provide an
22634 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
22635 and policy files. For example, to allow avahi-daemon to use the system bus,
22636 @var{services} must be equal to @code{(list avahi)}.
22639 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
22640 Return a service that runs the @code{elogind} login and
22641 seat management daemon. @uref{https://github.com/elogind/elogind,
22642 Elogind} exposes a D-Bus interface that can be used to know which users
22643 are logged in, know what kind of sessions they have open, suspend the
22644 system, inhibit system suspend, reboot the system, and other tasks.
22646 Elogind handles most system-level power events for a computer, for
22647 example suspending the system when a lid is closed, or shutting it down
22648 when the power button is pressed.
22650 The @var{config} keyword argument specifies the configuration for
22651 elogind, and should be the result of an @code{(elogind-configuration
22652 (@var{parameter} @var{value})...)} invocation. Available parameters and
22653 their default values are:
22656 @item kill-user-processes?
22658 @item kill-only-users
22660 @item kill-exclude-users
22662 @item inhibit-delay-max-seconds
22664 @item handle-power-key
22666 @item handle-suspend-key
22668 @item handle-hibernate-key
22670 @item handle-lid-switch
22672 @item handle-lid-switch-docked
22674 @item handle-lid-switch-external-power
22675 @code{*unspecified*}
22676 @item power-key-ignore-inhibited?
22678 @item suspend-key-ignore-inhibited?
22680 @item hibernate-key-ignore-inhibited?
22682 @item lid-switch-ignore-inhibited?
22684 @item holdoff-timeout-seconds
22688 @item idle-action-seconds
22690 @item runtime-directory-size-percent
22692 @item runtime-directory-size
22696 @item suspend-state
22697 @code{("mem" "standby" "freeze")}
22700 @item hibernate-state
22702 @item hibernate-mode
22703 @code{("platform" "shutdown")}
22704 @item hybrid-sleep-state
22706 @item hybrid-sleep-mode
22707 @code{("suspend" "platform" "shutdown")}
22711 @deffn {Scheme Procedure} accountsservice-service @
22712 [#:accountsservice @var{accountsservice}]
22713 Return a service that runs AccountsService, a system service that can
22714 list available accounts, change their passwords, and so on.
22715 AccountsService integrates with PolicyKit to enable unprivileged users
22716 to acquire the capability to modify their system configuration.
22717 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
22718 accountsservice web site} for more information.
22720 The @var{accountsservice} keyword argument is the @code{accountsservice}
22721 package to expose as a service.
22724 @deffn {Scheme Procedure} polkit-service @
22725 [#:polkit @var{polkit}]
22726 Return a service that runs the
22727 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
22728 management service}, which allows system administrators to grant access to
22729 privileged operations in a structured way. By querying the Polkit service, a
22730 privileged system component can know when it should grant additional
22731 capabilities to ordinary users. For example, an ordinary user can be granted
22732 the capability to suspend the system if the user is logged in locally.
22735 @defvr {Scheme Variable} polkit-wheel-service
22736 Service that adds the @code{wheel} group as admins to the Polkit
22737 service. This makes it so that users in the @code{wheel} group are queried
22738 for their own passwords when performing administrative actions instead of
22739 @code{root}'s, similar to the behaviour used by @code{sudo}.
22742 @defvr {Scheme Variable} upower-service-type
22743 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
22744 system-wide monitor for power consumption and battery levels, with the given
22745 configuration settings.
22747 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
22748 notably used by GNOME.
22751 @deftp {Data Type} upower-configuration
22752 Data type representation the configuration for UPower.
22756 @item @code{upower} (default: @var{upower})
22757 Package to use for @code{upower}.
22759 @item @code{watts-up-pro?} (default: @code{#f})
22760 Enable the Watts Up Pro device.
22762 @item @code{poll-batteries?} (default: @code{#t})
22763 Enable polling the kernel for battery level changes.
22765 @item @code{ignore-lid?} (default: @code{#f})
22766 Ignore the lid state, this can be useful if it's incorrect on a device.
22768 @item @code{use-percentage-for-policy?} (default: @code{#t})
22769 Whether a to use a policy based on battery percentage rather than on
22770 estimated time left. A policy based on battery percentage is usually
22773 @item @code{percentage-low} (default: @code{20})
22774 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22775 at which the battery is considered low.
22777 @item @code{percentage-critical} (default: @code{5})
22778 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22779 at which the battery is considered critical.
22781 @item @code{percentage-action} (default: @code{2})
22782 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22783 at which action will be taken.
22785 @item @code{time-low} (default: @code{1200})
22786 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22787 seconds at which the battery is considered low.
22789 @item @code{time-critical} (default: @code{300})
22790 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22791 seconds at which the battery is considered critical.
22793 @item @code{time-action} (default: @code{120})
22794 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22795 seconds at which action will be taken.
22797 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
22798 The action taken when @code{percentage-action} or @code{time-action} is
22799 reached (depending on the configuration of @code{use-percentage-for-policy?}).
22801 Possible values are:
22811 @code{'hybrid-sleep}.
22817 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
22818 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
22819 UDisks}, a @dfn{disk management} daemon that provides user interfaces
22820 with notifications and ways to mount/unmount disks. Programs that talk
22821 to UDisks include the @command{udisksctl} command, part of UDisks, and
22822 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
22823 it will only be able to use the file-system utilities installed in the
22824 system profile. For example if you want to be able to mount NTFS
22825 file-systems in read and write fashion, you'll need to have
22826 @code{ntfs-3g} installed system-wide.
22829 @deffn {Scheme Variable} colord-service-type
22830 This is the type of the service that runs @command{colord}, a system
22831 service with a D-Bus
22832 interface to manage the color profiles of input and output devices such as
22833 screens and scanners. It is notably used by the GNOME Color Manager graphical
22834 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
22835 site} for more information.
22838 @cindex scanner access
22839 @defvr {Scheme Variable} sane-service-type
22840 This service provides access to scanners @i{via}
22841 @uref{http://www.sane-project.org, SANE} by installing the necessary
22842 udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
22843 Services}) and relies by default on @code{sane-backends-minimal} package
22844 (see below) for hardware support.
22847 @defvr {Scheme Variable} sane-backends-minimal
22848 The default package which the @code{sane-service-type} installs. It
22849 supports many recent scanners.
22852 @defvr {Scheme Variable} sane-backends
22853 This package includes support for all scanners that
22854 @code{sane-backends-minimal} supports, plus older Hewlett-Packard
22855 scanners supported by @code{hplip} package. In order to use this on
22856 a system which relies on @code{%desktop-services}, you may use
22857 @code{modify-services} (@pxref{Service Reference,
22858 @code{modify-services}}) as illustrated below:
22861 (use-modules (gnu))
22862 (use-service-modules
22865 (use-package-modules
22869 (define %my-desktop-services
22870 ;; List of desktop services that supports a broader range of scanners.
22871 (modify-services %desktop-services
22872 (sane-service-type _ => sane-backends)))
22876 (services %my-desktop-services))
22880 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
22881 Return a configuration allowing an application to access GeoClue
22882 location data. @var{name} is the Desktop ID of the application, without
22883 the @code{.desktop} part. If @var{allowed?} is true, the application
22884 will have access to location information by default. The boolean
22885 @var{system?} value indicates whether an application is a system component
22886 or not. Finally @var{users} is a list of UIDs of all users for which
22887 this application is allowed location info access. An empty users list
22888 means that all users are allowed.
22891 @defvr {Scheme Variable} %standard-geoclue-applications
22892 The standard list of well-known GeoClue application configurations,
22893 granting authority to the GNOME date-and-time utility to ask for the
22894 current location in order to set the time zone, and allowing the
22895 IceCat and Epiphany web browsers to request location information.
22896 IceCat and Epiphany both query the user before allowing a web page to
22897 know the user's location.
22900 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
22901 [#:whitelist '()] @
22902 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
22903 [#:submit-data? #f]
22904 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
22905 [#:submission-nick "geoclue"] @
22906 [#:applications %standard-geoclue-applications]
22907 Return a service that runs the GeoClue location service. This service
22908 provides a D-Bus interface to allow applications to request access to a
22909 user's physical location, and optionally to add information to online
22910 location databases. See
22911 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
22912 web site} for more information.
22915 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
22916 [@w{#:auto-enable? #f}]
22917 Return a service that runs the @command{bluetoothd} daemon, which
22918 manages all the Bluetooth devices and provides a number of D-Bus
22919 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
22920 powered automatically at boot, which can be useful when using a
22921 bluetooth keyboard or mouse.
22923 Users need to be in the @code{lp} group to access the D-Bus service.
22926 @deffn {Scheme Variable} bluetooth-service-type
22927 This is the type for the @uref{https://bluez.org/, Linux Bluetooth Protocol
22928 Stack} (BlueZ) system, which generates the @file{/etc/bluetooth/main.conf}
22929 configuration file. The value for this type is a @command{bluetooth-configuration}
22930 record as in this example:
22933 (service bluetooth-service-type)
22936 See below for details about @code{bluetooth-configuration}.
22939 @deftp {Data Type} bluetooth-configuration
22940 Data type representing the configuration for @code{bluetooth-service}.
22943 @item @code{bluez} (default: @code{bluez})
22944 @code{bluez} package to use.
22946 @item @code{name} (default: @code{"BlueZ"})
22947 Default adapter name.
22949 @item @code{class} (default: @code{#x000000})
22950 Default device class. Only the major and minor device class bits are considered.
22952 @item @code{discoverable-timeout} (default: @code{180})
22953 How long to stay in discoverable mode before going back to non-discoverable. The
22954 value is in seconds.
22956 @item @code{always-pairable?} (default: @code{#f})
22957 Always allow pairing even if there are no agents registered.
22959 @item @code{pairable-timeout} (default: @code{0})
22960 How long to stay in pairable mode before going back to non-discoverable. The
22961 value is in seconds.
22963 @item @code{device-id} (default: @code{#f})
22964 Use vendor id source (assigner), vendor, product and version information for
22965 DID profile support. The values are separated by ":" and @var{assigner}, @var{VID},
22966 @var{PID} and @var{version}.
22968 Possible values are:
22972 @code{#f} to disable it,
22975 @code{"assigner:1234:5678:abcd"}, where @var{assigner} is either @code{usb} (default)
22976 or @code{bluetooth}.
22980 @item @code{reverse-service-discovery?} (default: @code{#t})
22981 Do reverse service discovery for previously unknown devices that connect to
22982 us. For BR/EDR this option is really only needed for qualification since the
22983 BITE tester doesn't like us doing reverse SDP for some test cases, for LE
22984 this disables the GATT client functionally so it can be used in system which
22985 can only operate as peripheral.
22987 @item @code{name-resolving?} (default: @code{#t})
22988 Enable name resolving after inquiry. Set it to @code{#f} if you don't need
22989 remote devices name and want shorter discovery cycle.
22991 @item @code{debug-keys?} (default: @code{#f})
22992 Enable runtime persistency of debug link keys. Default is false which makes
22993 debug link keys valid only for the duration of the connection that they were
22996 @item @code{controller-mode} (default: @code{'dual})
22997 Restricts all controllers to the specified transport. @code{'dual} means both
22998 BR/EDR and LE are enabled (if supported by the hardware).
23000 Possible values are:
23014 @item @code{multi-profile} (default: @code{'off})
23015 Enables Multi Profile Specification support. This allows to specify if system
23016 supports only Multiple Profiles Single Device (MPSD) configuration or both
23017 Multiple Profiles Single Device (MPSD) and Multiple Profiles Multiple Devices
23018 (MPMD) configurations.
23020 Possible values are:
23034 @item @code{fast-connectable?} (default: @code{#f})
23035 Permanently enables the Fast Connectable setting for adapters that support
23036 it. When enabled other devices can connect faster to us, however the
23037 tradeoff is increased power consumptions. This feature will fully work only
23038 on kernel version 4.1 and newer.
23040 @item @code{privacy} (default: @code{'off})
23041 Default privacy settings.
23045 @code{'off}: Disable local privacy
23048 @code{'network/on}: A device will only accept advertising packets from peer
23049 devices that contain private addresses. It may not be compatible with some
23050 legacy devices since it requires the use of RPA(s) all the time
23053 @code{'device}: A device in device privacy mode is only concerned about the
23054 privacy of the device and will accept advertising packets from peer devices
23055 that contain their Identity Address as well as ones that contain a private
23056 address, even if the peer device has distributed its IRK in the past
23060 and additionally, if @var{controller-mode} is set to @code{'dual}:
23064 @code{'limited-network}: Apply Limited Discoverable Mode to advertising, which
23065 follows the same policy as to BR/EDR that publishes the identity address when
23066 discoverable, and Network Privacy Mode for scanning
23069 @code{'limited-device}: Apply Limited Discoverable Mode to advertising, which
23070 follows the same policy as to BR/EDR that publishes the identity address when
23071 discoverable, and Device Privacy Mode for scanning.
23075 @item @code{just-works-repairing} (default: @code{'never})
23076 Specify the policy to the JUST-WORKS repairing initiated by peer.
23091 @item @code{temporary-timeout} (default: @code{30})
23092 How long to keep temporary devices around. The value is in seconds. @code{0}
23093 disables the timer completely.
23095 @item @code{refresh-discovery?} (default: @code{#t})
23096 Enables the device to issue an SDP request to update known services when
23097 profile is connected.
23099 @item @code{experimental} (default: @code{#f})
23100 Enables experimental features and interfaces, alternatively a list of UUIDs
23113 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
23116 List of possible UUIDs:
23119 @code{d4992530-b9ec-469f-ab01-6c481c47da1c}: BlueZ Experimental Debug,
23122 @code{671b10b5-42c0-4696-9227-eb28d1b049d6}: BlueZ Experimental Simultaneous Central and Peripheral,
23125 @code{"15c0a148-c273-11ea-b3de-0242ac130004}: BlueZ Experimental LL privacy,
23128 @code{330859bc-7506-492d-9370-9a6f0614037f}: BlueZ Experimental Bluetooth Quality Report,
23131 @code{a6695ace-ee7f-4fb9-881a-5fac66c629af}: BlueZ Experimental Offload Codecs.
23134 @item @code{remote-name-request-retry-delay} (default: @code{300})
23135 The duration to avoid retrying to resolve a peer's name, if the previous
23138 @item @code{page-scan-type} (default: @code{#f})
23139 BR/EDR Page scan activity type.
23141 @item @code{page-scan-interval} (default: @code{#f})
23142 BR/EDR Page scan activity interval.
23144 @item @code{page-scan-window} (default: @code{#f})
23145 BR/EDR Page scan activity window.
23147 @item @code{inquiry-scan-type} (default: @code{#f})
23148 BR/EDR Inquiry scan activity type.
23150 @item @code{inquiry-scan-interval} (default: @code{#f})
23151 BR/EDR Inquiry scan activity interval.
23153 @item @code{inquiry-scan-window} (default: @code{#f})
23154 BR/EDR Inquiry scan activity window.
23156 @item @code{link-supervision-timeout} (default: @code{#f})
23157 BR/EDR Link supervision timeout.
23159 @item @code{page-timeout} (default: @code{#f})
23160 BR/EDR Page timeout.
23162 @item @code{min-sniff-interval} (default: @code{#f})
23163 BR/EDR minimum sniff interval.
23165 @item @code{max-sniff-interval} (default: @code{#f})
23166 BR/EDR maximum sniff interval.
23168 @item @code{min-advertisement-interval} (default: @code{#f})
23169 LE minimum advertisement interval (used for legacy advertisement only).
23171 @item @code{max-advertisement-interval} (default: @code{#f})
23172 LE maximum advertisement interval (used for legacy advertisement only).
23174 @item @code{multi-advertisement-rotation-interval} (default: @code{#f})
23175 LE multiple advertisement rotation interval.
23177 @item @code{scan-interval-auto-connect} (default: @code{#f})
23178 LE scanning interval used for passive scanning supporting auto connect.
23180 @item @code{scan-window-auto-connect} (default: @code{#f})
23181 LE scanning window used for passive scanning supporting auto connect.
23183 @item @code{scan-interval-suspend} (default: @code{#f})
23184 LE scanning interval used for active scanning supporting wake from suspend.
23186 @item @code{scan-window-suspend} (default: @code{#f})
23187 LE scanning window used for active scanning supporting wake from suspend.
23189 @item @code{scan-interval-discovery} (default: @code{#f})
23190 LE scanning interval used for active scanning supporting discovery.
23192 @item @code{scan-window-discovery} (default: @code{#f})
23193 LE scanning window used for active scanning supporting discovery.
23195 @item @code{scan-interval-adv-monitor} (default: @code{#f})
23196 LE scanning interval used for passive scanning supporting the advertisement monitor APIs.
23198 @item @code{scan-window-adv-monitor} (default: @code{#f})
23199 LE scanning window used for passive scanning supporting the advertisement monitor APIs.
23201 @item @code{scan-interval-connect} (default: @code{#f})
23202 LE scanning interval used for connection establishment.
23204 @item @code{scan-window-connect} (default: @code{#f})
23205 LE scanning window used for connection establishment.
23207 @item @code{min-connection-interval} (default: @code{#f})
23208 LE default minimum connection interval. This value is superseded by any specific
23209 value provided via the Load Connection Parameters interface.
23211 @item @code{max-connection-interval} (default: @code{#f})
23212 LE default maximum connection interval. This value is superseded by any specific
23213 value provided via the Load Connection Parameters interface.
23215 @item @code{connection-latency} (default: @code{#f})
23216 LE default connection latency. This value is superseded by any specific
23217 value provided via the Load Connection Parameters interface.
23219 @item @code{connection-supervision-timeout} (default: @code{#f})
23220 LE default connection supervision timeout. This value is superseded by any specific
23221 value provided via the Load Connection Parameters interface.
23223 @item @code{autoconnect-timeout} (default: @code{#f})
23224 LE default autoconnect timeout. This value is superseded by any specific
23225 value provided via the Load Connection Parameters interface.
23227 @item @code{adv-mon-allowlist-scan-duration} (default: @code{300})
23228 Allowlist scan duration during interleaving scan. Only used when scanning for ADV
23229 monitors. The units are msec.
23231 @item @code{adv-mon-no-filter-scan-duration} (default: @code{500})
23232 No filter scan duration during interleaving scan. Only used when scanning for ADV
23233 monitors. The units are msec.
23235 @item @code{enable-adv-mon-interleave-scan?} (default: @code{#t})
23236 Enable/Disable Advertisement Monitor interleave scan for power saving.
23238 @item @code{cache} (default: @code{'always})
23239 GATT attribute cache.
23241 Possible values are:
23244 @code{'always}: Always cache attributes even for devices not paired, this is
23245 recommended as it is best for interoperability, with more consistent
23246 reconnection times and enables proper tracking of notifications for all
23250 @code{'yes}: Only cache attributes of paired devices
23253 @code{'no}: Never cache attributes.
23256 @item @code{key-size} (default: @code{0})
23257 Minimum required Encryption Key Size for accessing secured characteristics.
23259 Possible values are:
23262 @code{0}: Don't care
23265 @code{7 <= N <= 16}
23268 @item @code{exchange-mtu} (default: @code{517})
23269 Exchange MTU size. Possible values are:
23273 @code{23 <= N <= 517}
23276 @item @code{att-channels} (default: @code{3})
23277 Number of ATT channels. Possible values are:
23281 @code{1}: Disables EATT
23287 @item @code{session-mode} (default: @code{'basic})
23288 AVDTP L2CAP signalling channel mode.
23290 Possible values are:
23294 @code{'basic}: Use L2CAP basic mode
23297 @code{'ertm}: Use L2CAP enhanced retransmission mode.
23300 @item @code{stream-mode} (default: @code{'basic})
23301 AVDTP L2CAP transport channel mode.
23303 Possible values are:
23307 @code{'basic}: Use L2CAP basic mode
23310 @code{'streaming}: Use L2CAP streaming mode.
23313 @item @code{reconnect-uuids} (default: @code{'()})
23314 The ReconnectUUIDs defines the set of remote services that should try
23315 to be reconnected to in case of a link loss (link supervision
23316 timeout). The policy plugin should contain a sane set of values by
23317 default, but this list can be overridden here. By setting the list to
23318 empty the reconnection feature gets disabled.
23327 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
23330 @item @code{reconnect-attempts} (default: @code{7})
23331 Defines the number of attempts to reconnect after a link lost. Setting
23332 the value to 0 disables reconnecting feature.
23334 @item @code{reconnect-intervals} (default: @code{'(1 2 4 8 16 32 64)})
23335 Defines a list of intervals in seconds to use in between attempts. If
23336 the number of attempts defined in @var{reconnect-attempts} is bigger than
23337 the list of intervals the last interval is repeated until the last attempt.
23339 @item @code{auto-enable?} (default: @code{#f})
23340 Defines option to enable all controllers when they are found. This includes
23341 adapters present on start as well as adapters that are plugged in later on.
23343 @item @code{resume-delay} (default: @code{2})
23344 Audio devices that were disconnected due to suspend will be reconnected on
23345 resume. @var{resume-delay} determines the delay between when the controller
23346 resumes from suspend and a connection attempt is made. A longer delay is
23347 better for better co-existence with Wi-Fi. The value is in seconds.
23349 @item @code{rssi-sampling-period} (default: @code{#xFF})
23350 Default RSSI Sampling Period. This is used when a client registers an
23351 advertisement monitor and leaves the RSSISamplingPeriod unset.
23353 Possible values are:
23356 @code{#x0}: Report all advertisements
23359 @code{N = #xXX}: Report advertisements every N x 100 msec (range: #x01 to #xFE)
23362 @code{#xFF}: Report only one advertisement per device during monitoring period.
23368 @defvr {Scheme Variable} gnome-keyring-service-type
23369 This is the type of the service that adds the
23370 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
23371 value is a @code{gnome-keyring-configuration} object (see below).
23373 This service adds the @code{gnome-keyring} package to the system profile
23374 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
23375 a user's login keyring when they log in or setting its password with passwd.
23378 @deftp {Data Type} gnome-keyring-configuration
23379 Configuration record for the GNOME Keyring service.
23382 @item @code{keyring} (default: @code{gnome-keyring})
23383 The GNOME keyring package to use.
23385 @item @code{pam-services}
23386 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
23387 services to extend, where @var{service} is the name of an existing
23388 service to extend and @var{kind} is one of @code{login} or
23391 If @code{login} is given, it adds an optional
23392 @code{pam_gnome_keyring.so} to the auth block without arguments and to
23393 the session block with @code{auto_start}. If @code{passwd} is given, it
23394 adds an optional @code{pam_gnome_keyring.so} to the password block
23397 By default, this field contains ``gdm-password'' with the value @code{login}
23398 and ``passwd'' is with the value @code{passwd}.
23402 @defvr {Scheme Variable} seatd-service-type
23403 @uref{https://sr.ht/~kennylevinsen/seatd/, seatd} is a minimal seat
23406 Seat management takes care of mediating access to shared devices (graphics,
23407 input), without requiring the applications needing access to be root.
23412 ;; make sure seatd is running
23413 (service seatd-service-type))
23415 ;; normally one would want %base-services
23420 @code{seatd} operates over a UNIX domain socket, with @code{libseat}
23421 providing the client side of the protocol. Applications that acquire
23422 access to the shared resources via @code{seatd} (e.g. @code{sway})
23423 need to be able to talk to this socket.
23424 This can be achieved by adding the user they run under to the group
23425 owning @code{seatd}'s socket (usually ``seat''), like so:
23431 (supplementary-groups '("wheel" ; allow use of sudo, etc.
23432 "seat" ; seat management
23433 "audio" ; sound card
23434 "video" ; video devices such as webcams
23435 "cdrom")) ; the good ol' CD-ROM
23436 (comment "Bob's sister"))
23439 Depending on your setup, you will have to not only add regular users,
23440 but also system users to this group. For instance, some greetd greeters
23441 require graphics and therefore also need to negotiate with seatd.
23445 @deftp {Data Type} seatd-configuration
23446 Configuration record for the seatd daemon service.
23449 @item @code{seatd} (default: @code{seatd})
23450 The seatd package to use.
23452 @item @code{group} (default: @samp{"seat"})
23453 Group to own the seatd socket.
23455 @item @code{socket} (default: @samp{"/run/seatd.sock"})
23456 Where to create the seatd socket.
23458 @item @code{logfile} (default: @samp{"/var/log/seatd.log"})
23459 Log file to write to.
23461 @item @code{loglevel} (default: @samp{"error"})
23462 Log level to output logs. Possible values: @samp{"silent"}, @samp{"error"},
23463 @samp{"info"} and @samp{"debug"}.
23469 @node Sound Services
23470 @subsection Sound Services
23472 @cindex sound support
23474 @cindex PulseAudio, sound support
23476 The @code{(gnu services sound)} module provides a service to configure the
23477 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
23478 preferred ALSA output driver.
23480 @deffn {Scheme Variable} alsa-service-type
23481 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
23482 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
23483 configuration file. The value for this type is a @command{alsa-configuration}
23484 record as in this example:
23487 (service alsa-service-type)
23490 See below for details about @code{alsa-configuration}.
23493 @deftp {Data Type} alsa-configuration
23494 Data type representing the configuration for @code{alsa-service}.
23497 @item @code{alsa-plugins} (default: @var{alsa-plugins})
23498 @code{alsa-plugins} package to use.
23500 @item @code{pulseaudio?} (default: @var{#t})
23501 Whether ALSA applications should transparently be made to use the
23502 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
23504 Using PulseAudio allows you to run several sound-producing applications
23505 at the same time and to individual control them @i{via}
23506 @command{pavucontrol}, among other things.
23508 @item @code{extra-options} (default: @var{""})
23509 String to append to the @file{/etc/asound.conf} file.
23514 Individual users who want to override the system configuration of ALSA can do
23515 it with the @file{~/.asoundrc} file:
23518 # In guix, we have to specify the absolute path for plugins.
23520 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
23523 # Routing ALSA to jack:
23524 # <http://jackaudio.org/faq/routing_alsa.html>.
23528 0 system:playback_1
23529 1 system:playback_2
23546 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
23549 @deffn {Scheme Variable} pulseaudio-service-type
23550 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
23551 sound server. It exists to allow system overrides of the default settings
23552 via @code{pulseaudio-configuration}, see below.
23555 This service overrides per-user configuration files. If you want
23556 PulseAudio to honor configuration files in @file{~/.config/pulse} you
23557 have to unset the environment variables @env{PULSE_CONFIG} and
23558 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
23562 This service on its own does not ensure, that the @code{pulseaudio} package
23563 exists on your machine. It merely adds configuration files for it, as
23564 detailed below. In the (admittedly unlikely) case, that you find yourself
23565 without a @code{pulseaudio} package, consider enabling it through the
23566 @code{alsa-service-type} above.
23570 @deftp {Data Type} pulseaudio-configuration
23571 Data type representing the configuration for @code{pulseaudio-service}.
23574 @item @code{client-conf} (default: @code{'()})
23575 List of settings to set in @file{client.conf}.
23576 Accepts a list of strings or symbol-value pairs. A string will be
23577 inserted as-is with a newline added. A pair will be formatted as
23578 ``key = value'', again with a newline added.
23580 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
23581 List of settings to set in @file{daemon.conf}, formatted just like
23584 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
23585 Script file to use as @file{default.pa}. In case the
23586 @code{extra-script-files} field below is used, an @code{.include}
23587 directive pointing to @file{/etc/pulse/default.pa.d} is appended to the
23590 @item @code{extra-script-files} (default: @code{'()})
23591 A list of file-like objects defining extra PulseAudio scripts to run at
23592 the initialization of the @command{pulseaudio} daemon, after the main
23593 @code{script-file}. The scripts are deployed to the
23594 @file{/etc/pulse/default.pa.d} directory; they should have the
23595 @samp{.pa} file name extension. For a reference of the available
23596 commands, refer to @command{man pulse-cli-syntax}.
23598 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
23599 Script file to use as @file{system.pa}.
23602 The example below sets the default PulseAudio card profile, the default
23603 sink and the default source to use for a old SoundBlaster Audigy sound
23606 (pulseaudio-configuration
23607 (extra-script-files
23608 (list (plain-file "audigy.pa"
23610 set-card-profile alsa_card.pci-0000_01_01.0 \
23611 output:analog-surround-40+input:analog-mono
23612 set-default-source alsa_input.pci-0000_01_01.0.analog-mono
23613 set-default-sink alsa_output.pci-0000_01_01.0.analog-surround-40\n")))))
23616 Note that @code{pulseaudio-service-type} is part of
23617 @code{%desktop-services}; if your operating system declaration was
23618 derived from one of the desktop templates, you'll want to adjust the
23619 above example to modify the existing @code{pulseaudio-service-type} via
23620 @code{modify-services} (@pxref{Service Reference,
23621 @code{modify-services}}), instead of defining a new one.
23625 @deffn {Scheme Variable} ladspa-service-type
23626 This service sets the @var{LADSPA_PATH} variable, so that programs, which
23627 respect it, e.g. PulseAudio, can load LADSPA plugins.
23629 The following example will setup the service to enable modules from the
23630 @code{swh-plugins} package:
23633 (service ladspa-service-type
23634 (ladspa-configuration (plugins (list swh-plugins))))
23637 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
23642 @node Database Services
23643 @subsection Database Services
23647 The @code{(gnu services databases)} module provides the following services.
23649 @subsubheading PostgreSQL
23651 The following example describes a PostgreSQL service with the default
23655 (service postgresql-service-type
23656 (postgresql-configuration
23657 (postgresql postgresql-10)))
23660 If the services fails to start, it may be due to an incompatible
23661 cluster already present in @var{data-directory}. Adjust it (or, if you
23662 don't need the cluster anymore, delete @var{data-directory}), then
23663 restart the service.
23665 Peer authentication is used by default and the @code{postgres} user
23666 account has no shell, which prevents the direct execution of @code{psql}
23667 commands as this user. To use @code{psql}, you can temporarily log in
23668 as @code{postgres} using a shell, create a PostgreSQL superuser with the
23669 same name as one of the system users and then create the associated
23673 sudo -u postgres -s /bin/sh
23674 createuser --interactive
23675 createdb $MY_USER_LOGIN # Replace appropriately.
23678 @deftp {Data Type} postgresql-configuration
23679 Data type representing the configuration for the
23680 @code{postgresql-service-type}.
23683 @item @code{postgresql}
23684 PostgreSQL package to use for the service.
23686 @item @code{port} (default: @code{5432})
23687 Port on which PostgreSQL should listen.
23689 @item @code{locale} (default: @code{"en_US.utf8"})
23690 Locale to use as the default when creating the database cluster.
23692 @item @code{config-file} (default: @code{(postgresql-config-file)})
23693 The configuration file to use when running PostgreSQL@. The default
23694 behaviour uses the postgresql-config-file record with the default values
23697 @item @code{log-directory} (default: @code{"/var/log/postgresql"})
23698 The directory where @command{pg_ctl} output will be written in a file
23699 named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
23700 configuration errors for instance.
23702 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
23703 Directory in which to store the data.
23705 @item @code{extension-packages} (default: @code{'()})
23706 @cindex postgresql extension-packages
23707 Additional extensions are loaded from packages listed in
23708 @var{extension-packages}. Extensions are available at runtime. For instance,
23709 to create a geographic database using the @code{postgis} extension, a user can
23710 configure the postgresql-service as in this example:
23714 (use-package-modules databases geo)
23718 ;; postgresql is required to run `psql' but postgis is not required for
23719 ;; proper operation.
23720 (packages (cons* postgresql %base-packages))
23723 (service postgresql-service-type
23724 (postgresql-configuration
23725 (postgresql postgresql-10)
23726 (extension-packages (list postgis))))
23730 Then the extension becomes visible and you can initialise an empty geographic
23731 database in this way:
23735 > create database postgistest;
23736 > \connect postgistest;
23737 > create extension postgis;
23738 > create extension postgis_topology;
23741 There is no need to add this field for contrib extensions such as hstore or
23742 dblink as they are already loadable by postgresql. This field is only
23743 required to add extensions provided by other packages.
23748 @deftp {Data Type} postgresql-config-file
23749 Data type representing the PostgreSQL configuration file. As shown in
23750 the following example, this can be used to customize the configuration
23751 of PostgreSQL@. Note that you can use any G-expression or filename in
23752 place of this record, if you already have a configuration file you'd
23753 like to use for example.
23756 (service postgresql-service-type
23757 (postgresql-configuration
23759 (postgresql-config-file
23760 (log-destination "stderr")
23762 (plain-file "pg_hba.conf"
23764 local all all trust
23765 host all all 127.0.0.1/32 md5
23766 host all all ::1/128 md5"))
23768 '(("session_preload_libraries" "auto_explain")
23769 ("random_page_cost" 2)
23770 ("auto_explain.log_min_duration" "100 ms")
23771 ("work_mem" "500 MB")
23772 ("logging_collector" #t)
23773 ("log_directory" "/var/log/postgresql")))))))
23777 @item @code{log-destination} (default: @code{"syslog"})
23778 The logging method to use for PostgreSQL@. Multiple values are accepted,
23779 separated by commas.
23781 @item @code{hba-file} (default: @code{%default-postgres-hba})
23782 Filename or G-expression for the host-based authentication
23785 @item @code{ident-file} (default: @code{%default-postgres-ident})
23786 Filename or G-expression for the user name mapping configuration.
23788 @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
23789 Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
23790 is to listen for connections from client applications. If set to
23791 @code{""} PostgreSQL does not listen on any Unix-domain sockets, in
23792 which case only TCP/IP sockets can be used to connect to the server.
23794 By default, the @code{#false} value means the PostgreSQL default value
23795 will be used, which is currently @samp{/tmp}.
23797 @item @code{extra-config} (default: @code{'()})
23798 List of additional keys and values to include in the PostgreSQL config
23799 file. Each entry in the list should be a list where the first element
23800 is the key, and the remaining elements are the values.
23802 The values can be numbers, booleans or strings and will be mapped to
23803 PostgreSQL parameters types @code{Boolean}, @code{String},
23804 @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
23805 @uref{https://www.postgresql.org/docs/current/config-setting.html,
23811 @deffn {Scheme Variable} postgresql-role-service-type
23812 This service allows to create PostgreSQL roles and databases after
23813 PostgreSQL service start. Here is an example of its use.
23816 (service postgresql-role-service-type
23817 (postgresql-role-configuration
23819 (list (postgresql-role
23821 (create-database? #t))))))
23824 This service can be extended with extra roles, as in this
23828 (service-extension postgresql-role-service-type
23829 (const (postgresql-role
23831 (create-database? #t))))
23835 @deftp {Data Type} postgresql-role
23836 PostgreSQL manages database access permissions using the concept of
23837 roles. A role can be thought of as either a database user, or a group
23838 of database users, depending on how the role is set up. Roles can own
23839 database objects (for example, tables) and can assign privileges on
23840 those objects to other roles to control who has access to which objects.
23846 @item @code{permissions} (default: @code{'(createdb login)})
23847 The role permissions list. Supported permissions are @code{bypassrls},
23848 @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
23851 @item @code{create-database?} (default: @code{#f})
23852 Whether to create a database with the same name as the role.
23857 @deftp {Data Type} postgresql-role-configuration
23858 Data type representing the configuration of
23859 @var{postgresql-role-service-type}.
23862 @item @code{host} (default: @code{"/var/run/postgresql"})
23863 The PostgreSQL host to connect to.
23865 @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
23866 File name of the log file.
23868 @item @code{roles} (default: @code{'()})
23869 The initial PostgreSQL roles to create.
23873 @subsubheading MariaDB/MySQL
23875 @defvr {Scheme Variable} mysql-service-type
23876 This is the service type for a MySQL or MariaDB database server. Its value
23877 is a @code{mysql-configuration} object that specifies which package to use,
23878 as well as various settings for the @command{mysqld} daemon.
23881 @deftp {Data Type} mysql-configuration
23882 Data type representing the configuration of @var{mysql-service-type}.
23885 @item @code{mysql} (default: @var{mariadb})
23886 Package object of the MySQL database server, can be either @var{mariadb}
23889 For MySQL, a temporary root password will be displayed at activation time.
23890 For MariaDB, the root password is empty.
23892 @item @code{bind-address} (default: @code{"127.0.0.1"})
23893 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
23894 to bind to all available network interfaces.
23896 @item @code{port} (default: @code{3306})
23897 TCP port on which the database server listens for incoming connections.
23899 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
23900 Socket file to use for local (non-network) connections.
23902 @item @code{extra-content} (default: @code{""})
23903 Additional settings for the @file{my.cnf} configuration file.
23905 @item @code{extra-environment} (default: @code{#~'()})
23906 List of environment variables passed to the @command{mysqld} process.
23908 @item @code{auto-upgrade?} (default: @code{#t})
23909 Whether to automatically run @command{mysql_upgrade} after starting the
23910 service. This is necessary to upgrade the @dfn{system schema} after
23911 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
23912 be disabled if you would rather do that manually.
23917 @subsubheading Memcached
23919 @defvr {Scheme Variable} memcached-service-type
23920 This is the service type for the @uref{https://memcached.org/,
23921 Memcached} service, which provides a distributed in memory cache. The
23922 value for the service type is a @code{memcached-configuration} object.
23926 (service memcached-service-type)
23929 @deftp {Data Type} memcached-configuration
23930 Data type representing the configuration of memcached.
23933 @item @code{memcached} (default: @code{memcached})
23934 The Memcached package to use.
23936 @item @code{interfaces} (default: @code{'("0.0.0.0")})
23937 Network interfaces on which to listen.
23939 @item @code{tcp-port} (default: @code{11211})
23940 Port on which to accept connections.
23942 @item @code{udp-port} (default: @code{11211})
23943 Port on which to accept UDP connections on, a value of 0 will disable
23944 listening on a UDP socket.
23946 @item @code{additional-options} (default: @code{'()})
23947 Additional command line options to pass to @code{memcached}.
23951 @subsubheading Redis
23953 @defvr {Scheme Variable} redis-service-type
23954 This is the service type for the @uref{https://redis.io/, Redis}
23955 key/value store, whose value is a @code{redis-configuration} object.
23958 @deftp {Data Type} redis-configuration
23959 Data type representing the configuration of redis.
23962 @item @code{redis} (default: @code{redis})
23963 The Redis package to use.
23965 @item @code{bind} (default: @code{"127.0.0.1"})
23966 Network interface on which to listen.
23968 @item @code{port} (default: @code{6379})
23969 Port on which to accept connections on, a value of 0 will disable
23970 listening on a TCP socket.
23972 @item @code{working-directory} (default: @code{"/var/lib/redis"})
23973 Directory in which to store the database and related files.
23977 @node Mail Services
23978 @subsection Mail Services
23982 The @code{(gnu services mail)} module provides Guix service definitions
23983 for email services: IMAP, POP3, and LMTP servers, as well as mail
23984 transport agents (MTAs). Lots of acronyms! These services are detailed
23985 in the subsections below.
23987 @subsubheading Dovecot Service
23989 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
23990 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
23993 By default, Dovecot does not need much configuration; the default
23994 configuration object created by @code{(dovecot-configuration)} will
23995 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
23996 certificate will be generated for TLS-protected connections, though
23997 Dovecot will also listen on cleartext ports by default. There are a
23998 number of options, though, which mail administrators might need to change,
23999 and as is the case with other services, Guix allows the system
24000 administrator to specify these parameters via a uniform Scheme interface.
24002 For example, to specify that mail is located at @code{maildir~/.mail},
24003 one would instantiate the Dovecot service like this:
24006 (dovecot-service #:config
24007 (dovecot-configuration
24008 (mail-location "maildir:~/.mail")))
24011 The available configuration parameters follow. Each parameter
24012 definition is preceded by its type; for example, @samp{string-list foo}
24013 indicates that the @code{foo} parameter should be specified as a list of
24014 strings. There is also a way to specify the configuration as a string,
24015 if you have an old @code{dovecot.conf} file that you want to port over
24016 from some other system; see the end for more details.
24018 @c The following documentation was initially generated by
24019 @c (generate-documentation) in (gnu services mail). Manually maintained
24020 @c documentation is better, so we shouldn't hesitate to edit below as
24021 @c needed. However if the change you want to make to this documentation
24022 @c can be done in an automated way, it's probably easier to change
24023 @c (generate-documentation) than to make it below and have to deal with
24024 @c the churn as dovecot updates.
24026 Available @code{dovecot-configuration} fields are:
24028 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
24029 The dovecot package.
24032 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
24033 A list of IPs or hosts where to listen for connections. @samp{*}
24034 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
24035 interfaces. If you want to specify non-default ports or anything more
24036 complex, customize the address and port fields of the
24037 @samp{inet-listener} of the specific services you are interested in.
24040 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
24041 List of protocols we want to serve. Available protocols include
24042 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
24044 Available @code{protocol-configuration} fields are:
24046 @deftypevr {@code{protocol-configuration} parameter} string name
24047 The name of the protocol.
24050 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
24051 UNIX socket path to the master authentication server to find users.
24052 This is used by imap (for shared users) and lda.
24053 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
24056 @deftypevr {@code{protocol-configuration} parameter} boolean imap-metadata?
24057 Whether to enable the @code{IMAP METADATA} extension as defined in
24058 @uref{https://tools.ietf.org/html/rfc5464,RFC@tie{}5464}, which provides
24059 a means for clients to set and retrieve per-mailbox, per-user metadata
24060 and annotations over IMAP.
24062 If this is @samp{#t}, you must also specify a dictionary @i{via} the
24063 @code{mail-attribute-dict} setting.
24065 Defaults to @samp{#f}.
24069 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-notify-capabilities
24070 Which NOTIFY capabilities to report to clients that first connect to
24071 the ManageSieve service, before authentication. These may differ from the
24072 capabilities offered to authenticated users. If this field is left empty,
24073 report what the Sieve interpreter supports by default.
24075 Defaults to @samp{()}.
24078 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-sieve-capability
24079 Which SIEVE capabilities to report to clients that first connect to
24080 the ManageSieve service, before authentication. These may differ from the
24081 capabilities offered to authenticated users. If this field is left empty,
24082 report what the Sieve interpreter supports by default.
24084 Defaults to @samp{()}.
24088 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
24089 Space separated list of plugins to load.
24092 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
24093 Maximum number of IMAP connections allowed for a user from each IP
24094 address. NOTE: The username is compared case-sensitively.
24095 Defaults to @samp{10}.
24100 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
24101 List of services to enable. Available services include @samp{imap},
24102 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
24105 Available @code{service-configuration} fields are:
24107 @deftypevr {@code{service-configuration} parameter} string kind
24108 The service kind. Valid values include @code{director},
24109 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
24110 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
24111 @code{tcpwrap}, @code{quota-warning}, or anything else.
24114 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
24115 Listeners for the service. A listener is either a
24116 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
24117 an @code{inet-listener-configuration}.
24118 Defaults to @samp{()}.
24120 Available @code{unix-listener-configuration} fields are:
24122 @deftypevr {@code{unix-listener-configuration} parameter} string path
24123 Path to the file, relative to @code{base-dir} field. This is also used as
24127 @deftypevr {@code{unix-listener-configuration} parameter} string mode
24128 The access mode for the socket.
24129 Defaults to @samp{"0600"}.
24132 @deftypevr {@code{unix-listener-configuration} parameter} string user
24133 The user to own the socket.
24134 Defaults to @samp{""}.
24137 @deftypevr {@code{unix-listener-configuration} parameter} string group
24138 The group to own the socket.
24139 Defaults to @samp{""}.
24143 Available @code{fifo-listener-configuration} fields are:
24145 @deftypevr {@code{fifo-listener-configuration} parameter} string path
24146 Path to the file, relative to @code{base-dir} field. This is also used as
24150 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
24151 The access mode for the socket.
24152 Defaults to @samp{"0600"}.
24155 @deftypevr {@code{fifo-listener-configuration} parameter} string user
24156 The user to own the socket.
24157 Defaults to @samp{""}.
24160 @deftypevr {@code{fifo-listener-configuration} parameter} string group
24161 The group to own the socket.
24162 Defaults to @samp{""}.
24166 Available @code{inet-listener-configuration} fields are:
24168 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
24169 The protocol to listen for.
24172 @deftypevr {@code{inet-listener-configuration} parameter} string address
24173 The address on which to listen, or empty for all addresses.
24174 Defaults to @samp{""}.
24177 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
24178 The port on which to listen.
24181 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
24182 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
24184 Defaults to @samp{#t}.
24189 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
24190 Maximum number of simultaneous client connections per process. Once
24191 this number of connections is received, the next incoming connection
24192 will prompt Dovecot to spawn another process. If set to 0,
24193 @code{default-client-limit} is used instead.
24195 Defaults to @samp{0}.
24199 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
24200 Number of connections to handle before starting a new process.
24201 Typically the only useful values are 0 (unlimited) or 1. 1 is more
24202 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
24203 Defaults to @samp{1}.
24207 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
24208 Maximum number of processes that can exist for this service. If set to
24209 0, @code{default-process-limit} is used instead.
24211 Defaults to @samp{0}.
24215 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
24216 Number of processes to always keep waiting for more connections.
24217 Defaults to @samp{0}.
24220 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
24221 If you set @samp{service-count 0}, you probably need to grow
24223 Defaults to @samp{256000000}.
24228 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
24229 Dict configuration, as created by the @code{dict-configuration}
24232 Available @code{dict-configuration} fields are:
24234 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
24235 A list of key-value pairs that this dict should hold.
24236 Defaults to @samp{()}.
24241 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
24242 A list of passdb configurations, each one created by the
24243 @code{passdb-configuration} constructor.
24245 Available @code{passdb-configuration} fields are:
24247 @deftypevr {@code{passdb-configuration} parameter} string driver
24248 The driver that the passdb should use. Valid values include
24249 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
24251 Defaults to @samp{"pam"}.
24254 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
24255 Space separated list of arguments to the passdb driver.
24256 Defaults to @samp{""}.
24261 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
24262 List of userdb configurations, each one created by the
24263 @code{userdb-configuration} constructor.
24265 Available @code{userdb-configuration} fields are:
24267 @deftypevr {@code{userdb-configuration} parameter} string driver
24268 The driver that the userdb should use. Valid values include
24269 @samp{passwd} and @samp{static}.
24270 Defaults to @samp{"passwd"}.
24273 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
24274 Space separated list of arguments to the userdb driver.
24275 Defaults to @samp{""}.
24278 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
24279 Override fields from passwd.
24280 Defaults to @samp{()}.
24285 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
24286 Plug-in configuration, created by the @code{plugin-configuration}
24290 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
24291 List of namespaces. Each item in the list is created by the
24292 @code{namespace-configuration} constructor.
24294 Available @code{namespace-configuration} fields are:
24296 @deftypevr {@code{namespace-configuration} parameter} string name
24297 Name for this namespace.
24300 @deftypevr {@code{namespace-configuration} parameter} string type
24301 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
24302 Defaults to @samp{"private"}.
24305 @deftypevr {@code{namespace-configuration} parameter} string separator
24306 Hierarchy separator to use. You should use the same separator for
24307 all namespaces or some clients get confused. @samp{/} is usually a good
24308 one. The default however depends on the underlying mail storage
24310 Defaults to @samp{""}.
24313 @deftypevr {@code{namespace-configuration} parameter} string prefix
24314 Prefix required to access this namespace. This needs to be
24315 different for all namespaces. For example @samp{Public/}.
24316 Defaults to @samp{""}.
24319 @deftypevr {@code{namespace-configuration} parameter} string location
24320 Physical location of the mailbox. This is in the same format as
24321 mail_location, which is also the default for it.
24322 Defaults to @samp{""}.
24325 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
24326 There can be only one INBOX, and this setting defines which
24328 Defaults to @samp{#f}.
24331 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
24332 If namespace is hidden, it's not advertised to clients via NAMESPACE
24333 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
24334 useful when converting from another server with different namespaces
24335 which you want to deprecate but still keep working. For example you can
24336 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
24338 Defaults to @samp{#f}.
24341 @deftypevr {@code{namespace-configuration} parameter} boolean list?
24342 Show the mailboxes under this namespace with the LIST command. This
24343 makes the namespace visible for clients that do not support the NAMESPACE
24344 extension. The special @code{children} value lists child mailboxes, but
24345 hides the namespace prefix.
24346 Defaults to @samp{#t}.
24349 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
24350 Namespace handles its own subscriptions. If set to @code{#f}, the
24351 parent namespace handles them. The empty prefix should always have this
24353 Defaults to @samp{#t}.
24356 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
24357 List of predefined mailboxes in this namespace.
24358 Defaults to @samp{()}.
24360 Available @code{mailbox-configuration} fields are:
24362 @deftypevr {@code{mailbox-configuration} parameter} string name
24363 Name for this mailbox.
24366 @deftypevr {@code{mailbox-configuration} parameter} string auto
24367 @samp{create} will automatically create this mailbox.
24368 @samp{subscribe} will both create and subscribe to the mailbox.
24369 Defaults to @samp{"no"}.
24372 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
24373 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
24374 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
24375 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
24376 Defaults to @samp{()}.
24383 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
24384 Base directory where to store runtime data.
24385 Defaults to @samp{"/var/run/dovecot/"}.
24388 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
24389 Greeting message for clients.
24390 Defaults to @samp{"Dovecot ready."}.
24393 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
24394 List of trusted network ranges. Connections from these IPs are
24395 allowed to override their IP addresses and ports (for logging and for
24396 authentication checks). @samp{disable-plaintext-auth} is also ignored
24397 for these networks. Typically you would specify your IMAP proxy servers
24399 Defaults to @samp{()}.
24402 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
24403 List of login access check sockets (e.g.@: tcpwrap).
24404 Defaults to @samp{()}.
24407 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
24408 Show more verbose process titles (in ps). Currently shows user name
24409 and IP address. Useful for seeing who is actually using the IMAP
24410 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
24412 Defaults to @samp{#f}.
24415 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
24416 Should all processes be killed when Dovecot master process shuts down.
24417 Setting this to @code{#f} means that Dovecot can be upgraded without
24418 forcing existing client connections to close (although that could also
24419 be a problem if the upgrade is e.g.@: due to a security fix).
24420 Defaults to @samp{#t}.
24423 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
24424 If non-zero, run mail commands via this many connections to doveadm
24425 server, instead of running them directly in the same process.
24426 Defaults to @samp{0}.
24429 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
24430 UNIX socket or host:port used for connecting to doveadm server.
24431 Defaults to @samp{"doveadm-server"}.
24434 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
24435 List of environment variables that are preserved on Dovecot startup
24436 and passed down to all of its child processes. You can also give
24437 key=value pairs to always set specific settings.
24440 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
24441 Disable LOGIN command and all other plaintext authentications unless
24442 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
24443 matches the local IP (i.e.@: you're connecting from the same computer),
24444 the connection is considered secure and plaintext authentication is
24445 allowed. See also ssl=required setting.
24446 Defaults to @samp{#t}.
24449 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
24450 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
24451 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
24452 for caching to be used.
24453 Defaults to @samp{0}.
24456 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
24457 Time to live for cached data. After TTL expires the cached record
24458 is no longer used, *except* if the main database lookup returns internal
24459 failure. We also try to handle password changes automatically: If
24460 user's previous authentication was successful, but this one wasn't, the
24461 cache isn't used. For now this works only with plaintext
24463 Defaults to @samp{"1 hour"}.
24466 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
24467 TTL for negative hits (user not found, password mismatch).
24468 0 disables caching them completely.
24469 Defaults to @samp{"1 hour"}.
24472 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
24473 List of realms for SASL authentication mechanisms that need them.
24474 You can leave it empty if you don't want to support multiple realms.
24475 Many clients simply use the first one listed here, so keep the default
24477 Defaults to @samp{()}.
24480 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
24481 Default realm/domain to use if none was specified. This is used for
24482 both SASL realms and appending @@domain to username in plaintext
24484 Defaults to @samp{""}.
24487 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
24488 List of allowed characters in username. If the user-given username
24489 contains a character not listed in here, the login automatically fails.
24490 This is just an extra check to make sure user can't exploit any
24491 potential quote escaping vulnerabilities with SQL/LDAP databases. If
24492 you want to allow all characters, set this value to empty.
24493 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
24496 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
24497 Username character translations before it's looked up from
24498 databases. The value contains series of from -> to characters. For
24499 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
24500 translated to @samp{@@}.
24501 Defaults to @samp{""}.
24504 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
24505 Username formatting before it's looked up from databases. You can
24506 use the standard variables here, e.g.@: %Lu would lowercase the username,
24507 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
24508 change the @samp{@@} into @samp{-AT-}. This translation is done after
24509 @samp{auth-username-translation} changes.
24510 Defaults to @samp{"%Lu"}.
24513 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
24514 If you want to allow master users to log in by specifying the master
24515 username within the normal username string (i.e.@: not using SASL
24516 mechanism's support for it), you can specify the separator character
24517 here. The format is then <username><separator><master username>.
24518 UW-IMAP uses @samp{*} as the separator, so that could be a good
24520 Defaults to @samp{""}.
24523 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
24524 Username to use for users logging in with ANONYMOUS SASL
24526 Defaults to @samp{"anonymous"}.
24529 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
24530 Maximum number of dovecot-auth worker processes. They're used to
24531 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
24532 They're automatically created and destroyed as needed.
24533 Defaults to @samp{30}.
24536 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
24537 Host name to use in GSSAPI principal names. The default is to use
24538 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
24539 allow all keytab entries.
24540 Defaults to @samp{""}.
24543 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
24544 Kerberos keytab to use for the GSSAPI mechanism. Will use the
24545 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
24546 need to change the auth service to run as root to be able to read this
24548 Defaults to @samp{""}.
24551 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
24552 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
24553 and @samp{ntlm-auth} helper.
24554 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
24555 Defaults to @samp{#f}.
24558 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
24559 Path for Samba's @samp{ntlm-auth} helper binary.
24560 Defaults to @samp{"/usr/bin/ntlm_auth"}.
24563 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
24564 Time to delay before replying to failed authentications.
24565 Defaults to @samp{"2 secs"}.
24568 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
24569 Require a valid SSL client certificate or the authentication
24571 Defaults to @samp{#f}.
24574 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
24575 Take the username from client's SSL certificate, using
24576 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
24578 Defaults to @samp{#f}.
24581 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
24582 List of wanted authentication mechanisms. Supported mechanisms are:
24583 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
24584 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
24585 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
24586 @samp{disable-plaintext-auth} setting.
24589 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
24590 List of IPs or hostnames to all director servers, including ourself.
24591 Ports can be specified as ip:port. The default port is the same as what
24592 director service's @samp{inet-listener} is using.
24593 Defaults to @samp{()}.
24596 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
24597 List of IPs or hostnames to all backend mail servers. Ranges are
24598 allowed too, like 10.0.0.10-10.0.0.30.
24599 Defaults to @samp{()}.
24602 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
24603 How long to redirect users to a specific server after it no longer
24604 has any connections.
24605 Defaults to @samp{"15 min"}.
24608 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
24609 How the username is translated before being hashed. Useful values
24610 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
24611 are shared within domain.
24612 Defaults to @samp{"%Lu"}.
24615 @deftypevr {@code{dovecot-configuration} parameter} string log-path
24616 Log file to use for error messages. @samp{syslog} logs to syslog,
24617 @samp{/dev/stderr} logs to stderr.
24618 Defaults to @samp{"syslog"}.
24621 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
24622 Log file to use for informational messages. Defaults to
24624 Defaults to @samp{""}.
24627 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
24628 Log file to use for debug messages. Defaults to
24629 @samp{info-log-path}.
24630 Defaults to @samp{""}.
24633 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
24634 Syslog facility to use if you're logging to syslog. Usually if you
24635 don't want to use @samp{mail}, you'll use local0..local7. Also other
24636 standard facilities are supported.
24637 Defaults to @samp{"mail"}.
24640 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
24641 Log unsuccessful authentication attempts and the reasons why they
24643 Defaults to @samp{#f}.
24646 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
24647 In case of password mismatches, log the attempted password. Valid
24648 values are no, plain and sha1. sha1 can be useful for detecting brute
24649 force password attempts vs. user simply trying the same password over
24650 and over again. You can also truncate the value to n chars by appending
24651 ":n" (e.g.@: sha1:6).
24652 Defaults to @samp{"no"}.
24655 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
24656 Even more verbose logging for debugging purposes. Shows for example
24658 Defaults to @samp{#f}.
24661 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
24662 In case of password mismatches, log the passwords and used scheme so
24663 the problem can be debugged. Enabling this also enables
24665 Defaults to @samp{#f}.
24668 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
24669 Enable mail process debugging. This can help you figure out why
24670 Dovecot isn't finding your mails.
24671 Defaults to @samp{#f}.
24674 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
24675 Show protocol level SSL errors.
24676 Defaults to @samp{#f}.
24679 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
24680 Prefix for each line written to log file. % codes are in
24681 strftime(3) format.
24682 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
24685 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
24686 List of elements we want to log. The elements which have a
24687 non-empty variable value are joined together to form a comma-separated
24691 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
24692 Login log format. %s contains @samp{login-log-format-elements}
24693 string, %$ contains the data we want to log.
24694 Defaults to @samp{"%$: %s"}.
24697 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
24698 Log prefix for mail processes. See doc/wiki/Variables.txt for list
24699 of possible variables you can use.
24700 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
24703 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
24704 Format to use for logging mail deliveries. You can use variables:
24707 Delivery status message (e.g.@: @samp{saved to INBOX})
24719 Defaults to @samp{"msgid=%m: %$"}.
24722 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
24723 Location for users' mailboxes. The default is empty, which means
24724 that Dovecot tries to find the mailboxes automatically. This won't work
24725 if the user doesn't yet have any mail, so you should explicitly tell
24726 Dovecot the full location.
24728 If you're using mbox, giving a path to the INBOX
24729 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
24730 where the other mailboxes are kept. This is called the @emph{root mail
24731 directory}, and it must be the first path given in the
24732 @samp{mail-location} setting.
24734 There are a few special variables you can use, e.g.:
24740 user part in user@@domain, same as %u if there's no domain
24742 domain part in user@@domain, empty if there's no domain
24747 See doc/wiki/Variables.txt for full list. Some examples:
24749 @item maildir:~/Maildir
24750 @item mbox:~/mail:INBOX=/var/mail/%u
24751 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
24753 Defaults to @samp{""}.
24756 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
24757 System user and group used to access mails. If you use multiple,
24758 userdb can override these by returning uid or gid fields. You can use
24759 either numbers or names. <doc/wiki/UserIds.txt>.
24760 Defaults to @samp{""}.
24763 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
24765 Defaults to @samp{""}.
24768 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
24769 Group to enable temporarily for privileged operations. Currently
24770 this is used only with INBOX when either its initial creation or
24771 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
24773 Defaults to @samp{""}.
24776 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
24777 Grant access to these supplementary groups for mail processes.
24778 Typically these are used to set up access to shared mailboxes. Note
24779 that it may be dangerous to set these if users can create symlinks
24780 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
24781 could allow a user to delete others' mailboxes, or @code{ln -s
24782 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
24786 @deftypevr {@code{dovecot-configuration} parameter} string mail-attribute-dict
24787 The location of a dictionary used to store @code{IMAP METADATA}
24788 as defined by @uref{https://tools.ietf.org/html/rfc5464, RFC@tie{}5464}.
24790 The IMAP METADATA commands are available only if the ``imap''
24791 protocol configuration's @code{imap-metadata?} field is @samp{#t}.
24793 Defaults to @samp{""}.
24797 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
24798 Allow full file system access to clients. There's no access checks
24799 other than what the operating system does for the active UID/GID@. It
24800 works with both maildir and mboxes, allowing you to prefix mailboxes
24801 names with e.g.@: @file{/path/} or @file{~user/}.
24802 Defaults to @samp{#f}.
24805 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
24806 Don't use @code{mmap()} at all. This is required if you store indexes to
24807 shared file systems (NFS or clustered file system).
24808 Defaults to @samp{#f}.
24811 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
24812 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
24813 supports @samp{O_EXCL} since version 3, so this should be safe to use
24814 nowadays by default.
24815 Defaults to @samp{#t}.
24818 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
24819 When to use fsync() or fdatasync() calls:
24822 Whenever necessary to avoid losing important data
24824 Useful with e.g.@: NFS when @code{write()}s are delayed
24826 Never use it (best performance, but crashes can lose data).
24828 Defaults to @samp{"optimized"}.
24831 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
24832 Mail storage exists in NFS@. Set this to yes to make Dovecot flush
24833 NFS caches whenever needed. If you're using only a single mail server
24835 Defaults to @samp{#f}.
24838 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
24839 Mail index files also exist in NFS@. Setting this to yes requires
24840 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
24841 Defaults to @samp{#f}.
24844 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
24845 Locking method for index files. Alternatives are fcntl, flock and
24846 dotlock. Dotlocking uses some tricks which may create more disk I/O
24847 than other locking methods. NFS users: flock doesn't work, remember to
24848 change @samp{mmap-disable}.
24849 Defaults to @samp{"fcntl"}.
24852 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
24853 Directory in which LDA/LMTP temporarily stores incoming mails >128
24855 Defaults to @samp{"/tmp"}.
24858 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
24859 Valid UID range for users. This is mostly to make sure that users can't
24860 log in as daemons or other system users. Note that denying root logins is
24861 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
24863 Defaults to @samp{500}.
24866 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
24868 Defaults to @samp{0}.
24871 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
24872 Valid GID range for users. Users having non-valid GID as primary group ID
24873 aren't allowed to log in. If user belongs to supplementary groups with
24874 non-valid GIDs, those groups are not set.
24875 Defaults to @samp{1}.
24878 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
24880 Defaults to @samp{0}.
24883 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
24884 Maximum allowed length for mail keyword name. It's only forced when
24885 trying to create new keywords.
24886 Defaults to @samp{50}.
24889 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
24890 List of directories under which chrooting is allowed for mail
24891 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
24892 too). This setting doesn't affect @samp{login-chroot}
24893 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
24894 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
24895 which local users can modify, that may lead to root exploit. Usually
24896 this should be done only if you don't allow shell access for users.
24897 <doc/wiki/Chrooting.txt>.
24898 Defaults to @samp{()}.
24901 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
24902 Default chroot directory for mail processes. This can be overridden
24903 for specific users in user database by giving @samp{/./} in user's home
24904 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
24905 there is no real need to do chrooting, Dovecot doesn't allow users to
24906 access files outside their mail directory anyway. If your home
24907 directories are prefixed with the chroot directory, append @samp{/.} to
24908 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
24909 Defaults to @samp{""}.
24912 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
24913 UNIX socket path to master authentication server to find users.
24914 This is used by imap (for shared users) and lda.
24915 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
24918 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
24919 Directory where to look up mail plugins.
24920 Defaults to @samp{"/usr/lib/dovecot"}.
24923 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
24924 List of plugins to load for all services. Plugins specific to IMAP,
24925 LDA, etc.@: are added to this list in their own .conf files.
24926 Defaults to @samp{()}.
24929 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
24930 The minimum number of mails in a mailbox before updates are done to
24931 cache file. This allows optimizing Dovecot's behavior to do less disk
24932 writes at the cost of more disk reads.
24933 Defaults to @samp{0}.
24936 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
24937 When IDLE command is running, mailbox is checked once in a while to
24938 see if there are any new mails or other changes. This setting defines
24939 the minimum time to wait between those checks. Dovecot can also use
24940 dnotify, inotify and kqueue to find out immediately when changes
24942 Defaults to @samp{"30 secs"}.
24945 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
24946 Save mails with CR+LF instead of plain LF@. This makes sending those
24947 mails take less CPU, especially with sendfile() syscall with Linux and
24948 FreeBSD@. But it also creates a bit more disk I/O which may just make it
24949 slower. Also note that if other software reads the mboxes/maildirs,
24950 they may handle the extra CRs wrong and cause problems.
24951 Defaults to @samp{#f}.
24954 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
24955 By default LIST command returns all entries in maildir beginning
24956 with a dot. Enabling this option makes Dovecot return only entries
24957 which are directories. This is done by stat()ing each entry, so it
24958 causes more disk I/O.
24959 (For systems setting struct @samp{dirent->d_type} this check is free
24960 and it's done always regardless of this setting).
24961 Defaults to @samp{#f}.
24964 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
24965 When copying a message, do it with hard links whenever possible.
24966 This makes the performance much better, and it's unlikely to have any
24968 Defaults to @samp{#t}.
24971 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
24972 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
24973 directory only when its mtime changes unexpectedly or when we can't find
24974 the mail otherwise.
24975 Defaults to @samp{#f}.
24978 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
24979 Which locking methods to use for locking mbox. There are four
24984 Create <mailbox>.lock file. This is the oldest and most NFS-safe
24985 solution. If you want to use /var/mail/ like directory, the users will
24986 need write access to that directory.
24988 Same as dotlock, but if it fails because of permissions or because there
24989 isn't enough disk space, just skip it.
24991 Use this if possible. Works with NFS too if lockd is used.
24993 May not exist in all systems. Doesn't work with NFS.
24995 May not exist in all systems. Doesn't work with NFS.
24998 You can use multiple locking methods; if you do the order they're declared
24999 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
25000 locking methods as well. Some operating systems don't allow using some of
25001 them simultaneously.
25004 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
25008 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
25009 Maximum time to wait for lock (all of them) before aborting.
25010 Defaults to @samp{"5 mins"}.
25013 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
25014 If dotlock exists but the mailbox isn't modified in any way,
25015 override the lock file after this much time.
25016 Defaults to @samp{"2 mins"}.
25019 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
25020 When mbox changes unexpectedly we have to fully read it to find out
25021 what changed. If the mbox is large this can take a long time. Since
25022 the change is usually just a newly appended mail, it'd be faster to
25023 simply read the new mails. If this setting is enabled, Dovecot does
25024 this but still safely fallbacks to re-reading the whole mbox file
25025 whenever something in mbox isn't how it's expected to be. The only real
25026 downside to this setting is that if some other MUA changes message
25027 flags, Dovecot doesn't notice it immediately. Note that a full sync is
25028 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
25029 Defaults to @samp{#t}.
25032 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
25033 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
25034 EXAMINE, EXPUNGE or CHECK commands. If this is set,
25035 @samp{mbox-dirty-syncs} is ignored.
25036 Defaults to @samp{#f}.
25039 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
25040 Delay writing mbox headers until doing a full write sync (EXPUNGE
25041 and CHECK commands and when closing the mailbox). This is especially
25042 useful for POP3 where clients often delete all mails. The downside is
25043 that our changes aren't immediately visible to other MUAs.
25044 Defaults to @samp{#t}.
25047 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
25048 If mbox size is smaller than this (e.g.@: 100k), don't write index
25049 files. If an index file already exists it's still read, just not
25051 Defaults to @samp{0}.
25054 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
25055 Maximum dbox file size until it's rotated.
25056 Defaults to @samp{10000000}.
25059 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
25060 Maximum dbox file age until it's rotated. Typically in days. Day
25061 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
25063 Defaults to @samp{"1d"}.
25066 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
25067 When creating new mdbox files, immediately preallocate their size to
25068 @samp{mdbox-rotate-size}. This setting currently works only in Linux
25069 with some file systems (ext4, xfs).
25070 Defaults to @samp{#f}.
25073 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
25074 sdbox and mdbox support saving mail attachments to external files,
25075 which also allows single instance storage for them. Other backends
25076 don't support this for now.
25078 WARNING: This feature hasn't been tested much yet. Use at your own risk.
25080 Directory root where to store mail attachments. Disabled, if empty.
25081 Defaults to @samp{""}.
25084 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
25085 Attachments smaller than this aren't saved externally. It's also
25086 possible to write a plugin to disable saving specific attachments
25088 Defaults to @samp{128000}.
25091 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
25092 File system backend to use for saving attachments:
25095 No SiS done by Dovecot (but this might help FS's own deduplication)
25097 SiS with immediate byte-by-byte comparison during saving
25098 @item sis-queue posix
25099 SiS with delayed comparison and deduplication.
25101 Defaults to @samp{"sis posix"}.
25104 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
25105 Hash format to use in attachment filenames. You can add any text and
25106 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
25107 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
25108 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
25109 Defaults to @samp{"%@{sha1@}"}.
25112 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
25114 Defaults to @samp{100}.
25117 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
25119 Defaults to @samp{1000}.
25122 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
25123 Default VSZ (virtual memory size) limit for service processes.
25124 This is mainly intended to catch and kill processes that leak memory
25125 before they eat up everything.
25126 Defaults to @samp{256000000}.
25129 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
25130 Login user is internally used by login processes. This is the most
25131 untrusted user in Dovecot system. It shouldn't have access to anything
25133 Defaults to @samp{"dovenull"}.
25136 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
25137 Internal user is used by unprivileged processes. It should be
25138 separate from login user, so that login processes can't disturb other
25140 Defaults to @samp{"dovecot"}.
25143 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
25144 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
25145 Defaults to @samp{"required"}.
25148 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
25149 PEM encoded X.509 SSL/TLS certificate (public key).
25150 Defaults to @samp{"</etc/dovecot/default.pem"}.
25153 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
25154 PEM encoded SSL/TLS private key. The key is opened before
25155 dropping root privileges, so keep the key file unreadable by anyone but
25157 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
25160 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
25161 If key file is password protected, give the password here.
25162 Alternatively give it when starting dovecot with -p parameter. Since
25163 this file is often world-readable, you may want to place this setting
25164 instead to a different.
25165 Defaults to @samp{""}.
25168 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
25169 PEM encoded trusted certificate authority. Set this only if you
25170 intend to use @samp{ssl-verify-client-cert? #t}. The file should
25171 contain the CA certificate(s) followed by the matching
25172 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
25173 Defaults to @samp{""}.
25176 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
25177 Require that CRL check succeeds for client certificates.
25178 Defaults to @samp{#t}.
25181 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
25182 Request client to send a certificate. If you also want to require
25183 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
25184 Defaults to @samp{#f}.
25187 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
25188 Which field from certificate to use for username. commonName and
25189 x500UniqueIdentifier are the usual choices. You'll also need to set
25190 @samp{auth-ssl-username-from-cert? #t}.
25191 Defaults to @samp{"commonName"}.
25194 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
25195 Minimum SSL protocol version to accept.
25196 Defaults to @samp{"TLSv1"}.
25199 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
25200 SSL ciphers to use.
25201 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
25204 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
25205 SSL crypto device to use, for valid values run "openssl engine".
25206 Defaults to @samp{""}.
25209 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
25210 Address to use when sending rejection mails.
25211 %d expands to recipient domain.
25212 Defaults to @samp{"postmaster@@%d"}.
25215 @deftypevr {@code{dovecot-configuration} parameter} string hostname
25216 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
25217 and in LMTP replies. Default is the system's real hostname@@domain.
25218 Defaults to @samp{""}.
25221 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
25222 If user is over quota, return with temporary failure instead of
25224 Defaults to @samp{#f}.
25227 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
25228 Binary to use for sending mails.
25229 Defaults to @samp{"/usr/sbin/sendmail"}.
25232 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
25233 If non-empty, send mails via this SMTP host[:port] instead of
25235 Defaults to @samp{""}.
25238 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
25239 Subject: header to use for rejection mails. You can use the same
25240 variables as for @samp{rejection-reason} below.
25241 Defaults to @samp{"Rejected: %s"}.
25244 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
25245 Human readable error message for rejection mails. You can use
25258 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
25261 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
25262 Delimiter character between local-part and detail in email
25264 Defaults to @samp{"+"}.
25267 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
25268 Header where the original recipient address (SMTP's RCPT TO:
25269 address) is taken from if not available elsewhere. With dovecot-lda -a
25270 parameter overrides this. A commonly used header for this is
25272 Defaults to @samp{""}.
25275 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
25276 Should saving a mail to a nonexistent mailbox automatically create
25278 Defaults to @samp{#f}.
25281 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
25282 Should automatically created mailboxes be also automatically
25284 Defaults to @samp{#f}.
25287 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
25288 Maximum IMAP command line length. Some clients generate very long
25289 command lines with huge mailboxes, so you may need to raise this if you
25290 get "Too long argument" or "IMAP command line too large" errors
25292 Defaults to @samp{64000}.
25295 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
25296 IMAP logout format string:
25299 total number of bytes read from client
25301 total number of bytes sent to client.
25303 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
25304 Defaults to @samp{"in=%i out=%o deleted=%@{deleted@} expunged=%@{expunged@} trashed=%@{trashed@} hdr_count=%@{fetch_hdr_count@} hdr_bytes=%@{fetch_hdr_bytes@} body_count=%@{fetch_body_count@} body_bytes=%@{fetch_body_bytes@}"}.
25307 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
25308 Override the IMAP CAPABILITY response. If the value begins with '+',
25309 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
25310 Defaults to @samp{""}.
25313 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
25314 How long to wait between "OK Still here" notifications when client
25316 Defaults to @samp{"2 mins"}.
25319 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
25320 ID field names and values to send to clients. Using * as the value
25321 makes Dovecot use the default value. The following fields have default
25322 values currently: name, version, os, os-version, support-url,
25324 Defaults to @samp{""}.
25327 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
25328 ID fields sent by client to log. * means everything.
25329 Defaults to @samp{""}.
25332 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
25333 Workarounds for various client bugs:
25336 @item delay-newmail
25337 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
25338 CHECK commands. Some clients ignore them otherwise, for example OSX
25339 Mail (<v2.1). Outlook Express breaks more badly though, without this it
25340 may show user "Message no longer in server" errors. Note that OE6
25341 still breaks even with this workaround if synchronization is set to
25344 @item tb-extra-mailbox-sep
25345 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
25346 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
25347 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
25349 @item tb-lsub-flags
25350 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
25351 This makes Thunderbird realize they aren't selectable and show them
25352 greyed out, instead of only later giving "not selectable" popup error.
25354 Defaults to @samp{()}.
25357 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
25358 Host allowed in URLAUTH URLs sent by client. "*" allows all.
25359 Defaults to @samp{""}.
25363 Whew! Lots of configuration options. The nice thing about it though is
25364 that Guix has a complete interface to Dovecot's configuration
25365 language. This allows not only a nice way to declare configurations,
25366 but also offers reflective capabilities as well: users can write code to
25367 inspect and transform configurations from within Scheme.
25369 However, it could be that you just want to get a @code{dovecot.conf} up
25370 and running. In that case, you can pass an
25371 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
25372 @code{dovecot-service}. As its name indicates, an opaque configuration
25373 does not have easy reflective capabilities.
25375 Available @code{opaque-dovecot-configuration} fields are:
25377 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
25378 The dovecot package.
25381 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
25382 The contents of the @code{dovecot.conf}, as a string.
25385 For example, if your @code{dovecot.conf} is just the empty string, you
25386 could instantiate a dovecot service like this:
25389 (dovecot-service #:config
25390 (opaque-dovecot-configuration
25394 @subsubheading OpenSMTPD Service
25396 @deffn {Scheme Variable} opensmtpd-service-type
25397 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
25398 service, whose value should be an @code{opensmtpd-configuration} object
25399 as in this example:
25402 (service opensmtpd-service-type
25403 (opensmtpd-configuration
25404 (config-file (local-file "./my-smtpd.conf"))))
25408 @deftp {Data Type} opensmtpd-configuration
25409 Data type representing the configuration of opensmtpd.
25412 @item @code{package} (default: @var{opensmtpd})
25413 Package object of the OpenSMTPD SMTP server.
25415 @item @code{config-file} (default: @code{%default-opensmtpd-config-file})
25416 File-like object of the OpenSMTPD configuration file to use. By default
25417 it listens on the loopback network interface, and allows for mail from
25418 users and daemons on the local machine, as well as permitting email to
25419 remote servers. Run @command{man smtpd.conf} for more information.
25421 @item @code{setgid-commands?} (default: @code{#t})
25422 Make the following commands setgid to @code{smtpq} so they can be
25423 executed: @command{smtpctl}, @command{sendmail}, @command{send-mail},
25424 @command{makemap}, @command{mailq}, and @command{newaliases}.
25425 @xref{Setuid Programs}, for more information on setgid programs.
25429 @subsubheading Exim Service
25431 @cindex mail transfer agent (MTA)
25432 @cindex MTA (mail transfer agent)
25435 @deffn {Scheme Variable} exim-service-type
25436 This is the type of the @uref{https://exim.org, Exim} mail transfer
25437 agent (MTA), whose value should be an @code{exim-configuration} object
25438 as in this example:
25441 (service exim-service-type
25442 (exim-configuration
25443 (config-file (local-file "./my-exim.conf"))))
25447 In order to use an @code{exim-service-type} service you must also have a
25448 @code{mail-aliases-service-type} service present in your
25449 @code{operating-system} (even if it has no aliases).
25451 @deftp {Data Type} exim-configuration
25452 Data type representing the configuration of exim.
25455 @item @code{package} (default: @var{exim})
25456 Package object of the Exim server.
25458 @item @code{config-file} (default: @code{#f})
25459 File-like object of the Exim configuration file to use. If its value is
25460 @code{#f} then use the default configuration file from the package
25461 provided in @code{package}. The resulting configuration file is loaded
25462 after setting the @code{exim_user} and @code{exim_group} configuration
25468 @subsubheading Getmail service
25473 @deffn {Scheme Variable} getmail-service-type
25474 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
25475 mail retriever, whose value should be an @code{getmail-configuration}.
25478 Available @code{getmail-configuration} fields are:
25480 @deftypevr {@code{getmail-configuration} parameter} symbol name
25481 A symbol to identify the getmail service.
25483 Defaults to @samp{"unset"}.
25487 @deftypevr {@code{getmail-configuration} parameter} package package
25488 The getmail package to use.
25492 @deftypevr {@code{getmail-configuration} parameter} string user
25493 The user to run getmail as.
25495 Defaults to @samp{"getmail"}.
25499 @deftypevr {@code{getmail-configuration} parameter} string group
25500 The group to run getmail as.
25502 Defaults to @samp{"getmail"}.
25506 @deftypevr {@code{getmail-configuration} parameter} string directory
25507 The getmail directory to use.
25509 Defaults to @samp{"/var/lib/getmail/default"}.
25513 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
25514 The getmail configuration file to use.
25516 Available @code{getmail-configuration-file} fields are:
25518 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
25519 What mail account to retrieve mail from, and how to access that account.
25521 Available @code{getmail-retriever-configuration} fields are:
25523 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
25524 The type of mail retriever to use. Valid values include @samp{passwd}
25527 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
25531 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
25532 Username to login to the mail server with.
25534 Defaults to @samp{unset}.
25538 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
25539 Username to login to the mail server with.
25541 Defaults to @samp{unset}.
25545 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
25546 Port number to connect to.
25548 Defaults to @samp{#f}.
25552 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
25553 Override fields from passwd.
25555 Defaults to @samp{""}.
25559 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
25560 Override fields from passwd.
25562 Defaults to @samp{()}.
25566 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
25567 PEM-formatted key file to use for the TLS negotiation.
25569 Defaults to @samp{""}.
25573 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
25574 PEM-formatted certificate file to use for the TLS negotiation.
25576 Defaults to @samp{""}.
25580 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
25581 CA certificates to use.
25583 Defaults to @samp{""}.
25587 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
25588 Extra retriever parameters.
25590 Defaults to @samp{()}.
25596 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
25597 What to do with retrieved messages.
25599 Available @code{getmail-destination-configuration} fields are:
25601 @deftypevr {@code{getmail-destination-configuration} parameter} string type
25602 The type of mail destination. Valid values include @samp{Maildir},
25603 @samp{Mboxrd} and @samp{MDA_external}.
25605 Defaults to @samp{unset}.
25609 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
25610 The path option for the mail destination. The behaviour depends on the
25613 Defaults to @samp{""}.
25617 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
25618 Extra destination parameters
25620 Defaults to @samp{()}.
25626 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
25629 Available @code{getmail-options-configuration} fields are:
25631 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
25632 If set to @samp{0}, getmail will only print warnings and errors. A
25633 value of @samp{1} means that messages will be printed about retrieving
25634 and deleting messages. If set to @samp{2}, getmail will print messages
25635 about each of its actions.
25637 Defaults to @samp{1}.
25641 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
25642 If true, getmail will retrieve all available messages. Otherwise it
25643 will only retrieve messages it hasn't seen previously.
25645 Defaults to @samp{#t}.
25649 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
25650 If set to true, messages will be deleted from the server after
25651 retrieving and successfully delivering them. Otherwise, messages will
25652 be left on the server.
25654 Defaults to @samp{#f}.
25658 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
25659 Getmail will delete messages this number of days after seeing them, if
25660 they have been delivered. This means messages will be left on the
25661 server this number of days after delivering them. A value of @samp{0}
25662 disabled this feature.
25664 Defaults to @samp{0}.
25668 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
25669 Delete messages larger than this of bytes after retrieving them, even if
25670 the delete and delete-after options are disabled. A value of @samp{0}
25671 disables this feature.
25673 Defaults to @samp{0}.
25677 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
25678 Retrieve messages totalling up to this number of bytes before closing
25679 the session with the server. A value of @samp{0} disables this feature.
25681 Defaults to @samp{0}.
25685 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
25686 Don't retrieve messages larger than this number of bytes. A value of
25687 @samp{0} disables this feature.
25689 Defaults to @samp{0}.
25693 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
25694 If true, getmail will add a Delivered-To header to messages.
25696 Defaults to @samp{#t}.
25700 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
25701 If set, getmail adds a Received header to the messages.
25703 Defaults to @samp{#t}.
25707 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
25708 Getmail will record a log of its actions to the named file. A value of
25709 @samp{""} disables this feature.
25711 Defaults to @samp{""}.
25715 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
25716 If true, getmail will record a log of its actions using the system
25719 Defaults to @samp{#f}.
25723 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
25724 If true, getmail will log information about messages not retrieved and
25725 the reason for not retrieving them, as well as starting and ending
25728 Defaults to @samp{#f}.
25732 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
25733 Extra options to include.
25735 Defaults to @samp{()}.
25743 @deftypevr {@code{getmail-configuration} parameter} list idle
25744 A list of mailboxes that getmail should wait on the server for new mail
25745 notifications. This depends on the server supporting the IDLE
25748 Defaults to @samp{()}.
25752 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
25753 Environment variables to set for getmail.
25755 Defaults to @samp{()}.
25759 @subsubheading Mail Aliases Service
25761 @cindex email aliases
25762 @cindex aliases, for email addresses
25764 @deffn {Scheme Variable} mail-aliases-service-type
25765 This is the type of the service which provides @code{/etc/aliases},
25766 specifying how to deliver mail to users on this system.
25769 (service mail-aliases-service-type
25770 '(("postmaster" "bob")
25771 ("bob" "bob@@example.com" "bob@@example2.com")))
25775 The configuration for a @code{mail-aliases-service-type} service is an
25776 association list denoting how to deliver mail that comes to this
25777 system. Each entry is of the form @code{(alias addresses ...)}, with
25778 @code{alias} specifying the local alias and @code{addresses} specifying
25779 where to deliver this user's mail.
25781 The aliases aren't required to exist as users on the local system. In
25782 the above example, there doesn't need to be a @code{postmaster} entry in
25783 the @code{operating-system}'s @code{user-accounts} in order to deliver
25784 the @code{postmaster} mail to @code{bob} (which subsequently would
25785 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
25787 @subsubheading GNU Mailutils IMAP4 Daemon
25788 @cindex GNU Mailutils IMAP4 Daemon
25790 @deffn {Scheme Variable} imap4d-service-type
25791 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
25792 mailutils, GNU Mailutils Manual}), whose value should be an
25793 @code{imap4d-configuration} object as in this example:
25796 (service imap4d-service-type
25797 (imap4d-configuration
25798 (config-file (local-file "imap4d.conf"))))
25802 @deftp {Data Type} imap4d-configuration
25803 Data type representing the configuration of @command{imap4d}.
25806 @item @code{package} (default: @code{mailutils})
25807 The package that provides @command{imap4d}.
25809 @item @code{config-file} (default: @code{%default-imap4d-config-file})
25810 File-like object of the configuration file to use, by default it will listen
25811 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
25812 Mailutils Manual}, for details.
25817 @subsubheading Radicale Service
25821 @deffn {Scheme Variable} radicale-service-type
25822 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
25823 server whose value should be a @code{radicale-configuration}.
25826 @deftp {Data Type} radicale-configuration
25827 Data type representing the configuration of @command{radicale}.
25830 @item @code{package} (default: @code{radicale})
25831 The package that provides @command{radicale}.
25833 @item @code{config-file} (default: @code{%default-radicale-config-file})
25834 File-like object of the configuration file to use, by default it will listen
25835 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
25836 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
25841 @node Messaging Services
25842 @subsection Messaging Services
25847 The @code{(gnu services messaging)} module provides Guix service
25848 definitions for messaging services. Currently it provides the following
25851 @subsubheading Prosody Service
25853 @deffn {Scheme Variable} prosody-service-type
25854 This is the type for the @uref{https://prosody.im, Prosody XMPP
25855 communication server}. Its value must be a @code{prosody-configuration}
25856 record as in this example:
25859 (service prosody-service-type
25860 (prosody-configuration
25861 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
25864 (int-component-configuration
25865 (hostname "conference.example.net")
25867 (mod-muc (mod-muc-configuration)))))
25870 (virtualhost-configuration
25871 (domain "example.net"))))))
25874 See below for details about @code{prosody-configuration}.
25878 By default, Prosody does not need much configuration. Only one
25879 @code{virtualhosts} field is needed: it specifies the domain you wish
25882 You can perform various sanity checks on the generated configuration
25883 with the @code{prosodyctl check} command.
25885 Prosodyctl will also help you to import certificates from the
25886 @code{letsencrypt} directory so that the @code{prosody} user can access
25887 them. See @url{https://prosody.im/doc/letsencrypt}.
25890 prosodyctl --root cert import /etc/letsencrypt/live
25893 The available configuration parameters follow. Each parameter
25894 definition is preceded by its type; for example, @samp{string-list foo}
25895 indicates that the @code{foo} parameter should be specified as a list of
25896 strings. Types starting with @code{maybe-} denote parameters that won't
25897 show up in @code{prosody.cfg.lua} when their value is left unspecified.
25899 There is also a way to specify the configuration as a string, if you
25900 have an old @code{prosody.cfg.lua} file that you want to port over from
25901 some other system; see the end for more details.
25903 The @code{file-object} type designates either a file-like object
25904 (@pxref{G-Expressions, file-like objects}) or a file name.
25906 @c The following documentation was initially generated by
25907 @c (generate-documentation) in (gnu services messaging). Manually maintained
25908 @c documentation is better, so we shouldn't hesitate to edit below as
25909 @c needed. However if the change you want to make to this documentation
25910 @c can be done in an automated way, it's probably easier to change
25911 @c (generate-documentation) than to make it below and have to deal with
25912 @c the churn as Prosody updates.
25914 Available @code{prosody-configuration} fields are:
25916 @deftypevr {@code{prosody-configuration} parameter} package prosody
25917 The Prosody package.
25920 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
25921 Location of the Prosody data storage directory. See
25922 @url{https://prosody.im/doc/configure}.
25923 Defaults to @samp{"/var/lib/prosody"}.
25926 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
25927 Additional plugin directories. They are searched in all the specified
25928 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
25929 Defaults to @samp{()}.
25932 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
25933 Every virtual host and component needs a certificate so that clients and
25934 servers can securely verify its identity. Prosody will automatically load
25935 certificates/keys from the directory specified here.
25936 Defaults to @samp{"/etc/prosody/certs"}.
25939 @deftypevr {@code{prosody-configuration} parameter} string-list admins
25940 This is a list of accounts that are admins for the server. Note that you
25941 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
25942 @url{https://prosody.im/doc/creating_accounts}.
25943 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
25944 Defaults to @samp{()}.
25947 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
25948 Enable use of libevent for better performance under high load. See
25949 @url{https://prosody.im/doc/libevent}.
25950 Defaults to @samp{#f}.
25953 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
25954 This is the list of modules Prosody will load on startup. It looks for
25955 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
25956 Documentation on modules can be found at:
25957 @url{https://prosody.im/doc/modules}.
25958 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
25961 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
25962 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
25963 should you want to disable them then add them to this list.
25964 Defaults to @samp{()}.
25967 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
25968 Path to a text file where the shared groups are defined. If this path is
25969 empty then @samp{mod_groups} does nothing. See
25970 @url{https://prosody.im/doc/modules/mod_groups}.
25971 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
25974 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
25975 Disable account creation by default, for security. See
25976 @url{https://prosody.im/doc/creating_accounts}.
25977 Defaults to @samp{#f}.
25980 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
25981 These are the SSL/TLS-related settings. Most of them are disabled so to
25982 use Prosody's defaults. If you do not completely understand these options, do
25983 not add them to your config, it is easy to lower the security of your server
25984 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
25986 Available @code{ssl-configuration} fields are:
25988 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
25989 This determines what handshake to use.
25992 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
25993 Path to your private key file.
25996 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
25997 Path to your certificate file.
26000 @deftypevr {@code{ssl-configuration} parameter} file-object capath
26001 Path to directory containing root certificates that you wish Prosody to
26002 trust when verifying the certificates of remote servers.
26003 Defaults to @samp{"/etc/ssl/certs"}.
26006 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
26007 Path to a file containing root certificates that you wish Prosody to trust.
26008 Similar to @code{capath} but with all certificates concatenated together.
26011 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
26012 A list of verification options (these mostly map to OpenSSL's
26013 @code{set_verify()} flags).
26016 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
26017 A list of general options relating to SSL/TLS@. These map to OpenSSL's
26018 @code{set_options()}. For a full list of options available in LuaSec, see the
26022 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
26023 How long a chain of certificate authorities to check when looking for a
26024 trusted root certificate.
26027 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
26028 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
26029 clients, and in what order.
26032 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
26033 A path to a file containing parameters for Diffie-Hellman key exchange. You
26034 can create such a file with:
26035 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
26038 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
26039 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
26040 @samp{"secp384r1"}.
26043 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
26044 A list of ``extra'' verification options.
26047 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
26048 Password for encrypted private keys.
26053 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
26054 Whether to force all client-to-server connections to be encrypted or not.
26055 See @url{https://prosody.im/doc/modules/mod_tls}.
26056 Defaults to @samp{#f}.
26059 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
26060 Set of mechanisms that will never be offered. See
26061 @url{https://prosody.im/doc/modules/mod_saslauth}.
26062 Defaults to @samp{("DIGEST-MD5")}.
26065 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
26066 Whether to force all server-to-server connections to be encrypted or not.
26067 See @url{https://prosody.im/doc/modules/mod_tls}.
26068 Defaults to @samp{#f}.
26071 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
26072 Whether to require encryption and certificate authentication. This
26073 provides ideal security, but requires servers you communicate with to support
26074 encryption AND present valid, trusted certificates. See
26075 @url{https://prosody.im/doc/s2s#security}.
26076 Defaults to @samp{#f}.
26079 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
26080 Many servers don't support encryption or have invalid or self-signed
26081 certificates. You can list domains here that will not be required to
26082 authenticate using certificates. They will be authenticated using DNS@. See
26083 @url{https://prosody.im/doc/s2s#security}.
26084 Defaults to @samp{()}.
26087 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
26088 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
26089 valid certificates for some domains by specifying a list here. See
26090 @url{https://prosody.im/doc/s2s#security}.
26091 Defaults to @samp{()}.
26094 @deftypevr {@code{prosody-configuration} parameter} string authentication
26095 Select the authentication backend to use. The default provider stores
26096 passwords in plaintext and uses Prosody's configured data storage to store the
26097 authentication data. If you do not trust your server please see
26098 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
26099 about using the hashed backend. See also
26100 @url{https://prosody.im/doc/authentication}
26101 Defaults to @samp{"internal_plain"}.
26104 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
26105 Set logging options. Advanced logging configuration is not yet supported
26106 by the Prosody service. See @url{https://prosody.im/doc/logging}.
26107 Defaults to @samp{"*syslog"}.
26110 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
26111 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
26112 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
26115 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
26116 Maximum allowed size of the HTTP body (in bytes).
26119 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
26120 Some modules expose their own URL in various ways. This URL is built
26121 from the protocol, host and port used. If Prosody sits behind a proxy, the
26122 public URL will be @code{http-external-url} instead. See
26123 @url{https://prosody.im/doc/http#external_url}.
26126 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
26127 A host in Prosody is a domain on which user accounts can be created. For
26128 example if you want your users to have addresses like
26129 @samp{"john.smith@@example.com"} then you need to add a host
26130 @samp{"example.com"}. All options in this list will apply only to this host.
26133 The name @emph{virtual} host is used in configuration to avoid confusion with
26134 the actual physical host that Prosody is installed on. A single Prosody
26135 instance can serve many domains, each one defined as a VirtualHost entry in
26136 Prosody's configuration. Conversely a server that hosts a single domain would
26137 have just one VirtualHost entry.
26139 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
26142 Available @code{virtualhost-configuration} fields are:
26144 all these @code{prosody-configuration} fields: @code{admins}, @code{use-libevent?}, @code{modules-enabled}, @code{modules-disabled}, @code{groups-file}, @code{allow-registration?}, @code{ssl}, @code{c2s-require-encryption?}, @code{disable-sasl-mechanisms}, @code{s2s-require-encryption?}, @code{s2s-secure-auth?}, @code{s2s-insecure-domains}, @code{s2s-secure-domains}, @code{authentication}, @code{log}, @code{http-max-content-size}, @code{http-external-url}, @code{raw-content}, plus:
26145 @deftypevr {@code{virtualhost-configuration} parameter} string domain
26146 Domain you wish Prosody to serve.
26151 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
26152 Components are extra services on a server which are available to clients,
26153 usually on a subdomain of the main server (such as
26154 @samp{"mycomponent.example.com"}). Example components might be chatroom
26155 servers, user directories, or gateways to other protocols.
26157 Internal components are implemented with Prosody-specific plugins. To add an
26158 internal component, you simply fill the hostname field, and the plugin you wish
26159 to use for the component.
26161 See @url{https://prosody.im/doc/components}.
26162 Defaults to @samp{()}.
26164 Available @code{int-component-configuration} fields are:
26166 all these @code{prosody-configuration} fields: @code{admins}, @code{use-libevent?}, @code{modules-enabled}, @code{modules-disabled}, @code{groups-file}, @code{allow-registration?}, @code{ssl}, @code{c2s-require-encryption?}, @code{disable-sasl-mechanisms}, @code{s2s-require-encryption?}, @code{s2s-secure-auth?}, @code{s2s-insecure-domains}, @code{s2s-secure-domains}, @code{authentication}, @code{log}, @code{http-max-content-size}, @code{http-external-url}, @code{raw-content}, plus:
26167 @deftypevr {@code{int-component-configuration} parameter} string hostname
26168 Hostname of the component.
26171 @deftypevr {@code{int-component-configuration} parameter} string plugin
26172 Plugin you wish to use for the component.
26175 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
26176 Multi-user chat (MUC) is Prosody's module for allowing you to create
26177 hosted chatrooms/conferences for XMPP users.
26179 General information on setting up and using multi-user chatrooms can be found
26180 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
26181 which you should read if you are new to XMPP chatrooms.
26183 See also @url{https://prosody.im/doc/modules/mod_muc}.
26185 Available @code{mod-muc-configuration} fields are:
26187 @deftypevr {@code{mod-muc-configuration} parameter} string name
26188 The name to return in service discovery responses.
26189 Defaults to @samp{"Prosody Chatrooms"}.
26192 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
26193 If @samp{#t}, this will only allow admins to create new chatrooms.
26194 Otherwise anyone can create a room. The value @samp{"local"} restricts room
26195 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
26196 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
26197 restricts to service administrators only.
26198 Defaults to @samp{#f}.
26201 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
26202 Maximum number of history messages that will be sent to the member that has
26203 just joined the room.
26204 Defaults to @samp{20}.
26211 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
26212 External components use XEP-0114, which most standalone components
26213 support. To add an external component, you simply fill the hostname field. See
26214 @url{https://prosody.im/doc/components}.
26215 Defaults to @samp{()}.
26217 Available @code{ext-component-configuration} fields are:
26219 all these @code{prosody-configuration} fields: @code{admins}, @code{use-libevent?}, @code{modules-enabled}, @code{modules-disabled}, @code{groups-file}, @code{allow-registration?}, @code{ssl}, @code{c2s-require-encryption?}, @code{disable-sasl-mechanisms}, @code{s2s-require-encryption?}, @code{s2s-secure-auth?}, @code{s2s-insecure-domains}, @code{s2s-secure-domains}, @code{authentication}, @code{log}, @code{http-max-content-size}, @code{http-external-url}, @code{raw-content}, plus:
26220 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
26221 Password which the component will use to log in.
26224 @deftypevr {@code{ext-component-configuration} parameter} string hostname
26225 Hostname of the component.
26230 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
26231 Port(s) Prosody listens on for component connections.
26232 Defaults to @samp{(5347)}.
26235 @deftypevr {@code{prosody-configuration} parameter} string component-interface
26236 Interface Prosody listens on for component connections.
26237 Defaults to @samp{"127.0.0.1"}.
26240 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
26241 Raw content that will be added to the configuration file.
26244 It could be that you just want to get a @code{prosody.cfg.lua}
26245 up and running. In that case, you can pass an
26246 @code{opaque-prosody-configuration} record as the value of
26247 @code{prosody-service-type}. As its name indicates, an opaque configuration
26248 does not have easy reflective capabilities.
26249 Available @code{opaque-prosody-configuration} fields are:
26251 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
26252 The prosody package.
26255 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
26256 The contents of the @code{prosody.cfg.lua} to use.
26259 For example, if your @code{prosody.cfg.lua} is just the empty
26260 string, you could instantiate a prosody service like this:
26263 (service prosody-service-type
26264 (opaque-prosody-configuration
26265 (prosody.cfg.lua "")))
26268 @c end of Prosody auto-generated documentation
26270 @subsubheading BitlBee Service
26272 @cindex IRC (Internet Relay Chat)
26273 @cindex IRC gateway
26274 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
26275 interface to a variety of messaging protocols such as XMPP.
26277 @defvr {Scheme Variable} bitlbee-service-type
26278 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
26279 gateway daemon. Its value is a @code{bitlbee-configuration} (see
26282 To have BitlBee listen on port 6667 on localhost, add this line to your
26286 (service bitlbee-service-type)
26290 @deftp {Data Type} bitlbee-configuration
26291 This is the configuration for BitlBee, with the following fields:
26294 @item @code{interface} (default: @code{"127.0.0.1"})
26295 @itemx @code{port} (default: @code{6667})
26296 Listen on the network interface corresponding to the IP address
26297 specified in @var{interface}, on @var{port}.
26299 When @var{interface} is @code{127.0.0.1}, only local clients can
26300 connect; when it is @code{0.0.0.0}, connections can come from any
26301 networking interface.
26303 @item @code{bitlbee} (default: @code{bitlbee})
26304 The BitlBee package to use.
26306 @item @code{plugins} (default: @code{'()})
26307 List of plugin packages to use---e.g., @code{bitlbee-discord}.
26309 @item @code{extra-settings} (default: @code{""})
26310 Configuration snippet added as-is to the BitlBee configuration file.
26314 @subsubheading Quassel Service
26316 @cindex IRC (Internet Relay Chat)
26317 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
26318 meaning that one or more clients can attach to and detach from the
26321 @defvr {Scheme Variable} quassel-service-type
26322 This is the service type for the @url{https://quassel-irc.org/,Quassel}
26323 IRC backend daemon. Its value is a @code{quassel-configuration}
26327 @deftp {Data Type} quassel-configuration
26328 This is the configuration for Quassel, with the following fields:
26331 @item @code{quassel} (default: @code{quassel})
26332 The Quassel package to use.
26334 @item @code{interface} (default: @code{"::,0.0.0.0"})
26335 @item @code{port} (default: @code{4242})
26336 Listen on the network interface(s) corresponding to the IPv4 or IPv6
26337 interfaces specified in the comma delimited @var{interface}, on
26340 @item @code{loglevel} (default: @code{"Info"})
26341 The level of logging desired. Accepted values are Debug, Info, Warning
26346 @node Telephony Services
26347 @subsection Telephony Services
26349 @cindex telephony, services
26350 The @code{(gnu services telephony)} module contains Guix service
26351 definitions for telephony services. Currently it provides the following
26354 @subsubheading Jami
26356 @cindex jami, service
26358 This section describes how to configure a Jami server that can be used
26359 to host video (or audio) conferences, among other uses. The following
26360 example demonstrates how to specify Jami account archives (backups) to
26361 be provisioned automatically:
26364 (service jami-service-type
26365 (jami-configuration
26367 (list (jami-account
26368 (archive "/etc/jami/unencrypted-account-1.gz"))
26370 (archive "/etc/jami/unencrypted-account-2.gz"))))))
26373 When the accounts field is specified, the Jami account files of the
26374 service found under @file{/var/lib/jami} are recreated every time the
26377 Jami accounts and their corresponding backup archives can be generated
26378 using the @code{jami} or @code{jami-gnome} Jami clients. The accounts
26379 should not be password-protected, but it is wise to ensure their files
26380 are only readable by @samp{root}.
26382 The next example shows how to declare that only some contacts should be
26383 allowed to communicate with a given account:
26386 (service jami-service-type
26387 (jami-configuration
26389 (list (jami-account
26390 (archive "/etc/jami/unencrypted-account-1.gz")
26391 (peer-discovery? #t)
26392 (rendezvous-point? #t)
26394 '("1dbcb0f5f37324228235564b79f2b9737e9a008f"
26395 "2dbcb0f5f37324228235564b79f2b9737e9a008f")))))))
26398 In this mode, only the declared @code{allowed-contacts} can initiate
26399 communication with the Jami account. This can be used, for example,
26400 with rendezvous point accounts to create a private video conferencing
26403 To put the system administrator in full control of the conferences
26404 hosted on their system, the Jami service supports the following actions:
26407 # herd doc jami list-actions
26409 list-account-details
26410 list-banned-contacts
26419 The above actions aim to provide the most valuable actions for
26420 moderation purposes, not to cover the whole Jami API. Users wanting to
26421 interact with the Jami daemon from Guile may be interested in
26422 experimenting with the @code{(gnu build jami-service)} module, which
26423 powers the above Shepherd actions.
26425 @c TODO: This should be auto-generated from the doc already defined on
26426 @c the shepherd-actions themselves in (gnu services telephony).
26427 The @code{add-moderator} and @code{ban-contact} actions accept a contact
26428 @emph{fingerprint} (40 characters long hash) as first argument and an
26429 account fingerprint or username as second argument:
26432 # herd add-moderator jami 1dbcb0f5f37324228235564b79f2b9737e9a008f \
26433 f3345f2775ddfe07a4b0d95daea111d15fbc1199
26435 # herd list-moderators jami
26436 Moderators for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26437 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26441 In the case of @code{ban-contact}, the second username argument is
26442 optional; when omitted, the account is banned from all Jami accounts:
26445 # herd ban-contact jami 1dbcb0f5f37324228235564b79f2b9737e9a008f
26447 # herd list-banned-contacts jami
26448 Banned contacts for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26449 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26453 Banned contacts are also stripped from their moderation privileges.
26455 The @code{disable-account} action allows to completely disconnect an
26456 account from the network, making it unreachable, while
26457 @code{enable-account} does the inverse. They accept a single account
26458 username or fingerprint as first argument:
26461 # herd disable-account jami f3345f2775ddfe07a4b0d95daea111d15fbc1199
26463 # herd list-accounts jami
26464 The following Jami accounts are available:
26465 - f3345f2775ddfe07a4b0d95daea111d15fbc1199 (dummy) [disabled]
26469 The @code{list-account-details} action prints the detailed parameters of
26470 each accounts in the Recutils format, which means the @command{recsel}
26471 command can be used to select accounts of interest (@pxref{Selection
26472 Expressions,,,recutils, GNU recutils manual}). Note that period
26473 characters (@samp{.}) found in the account parameter keys are mapped to
26474 underscores (@samp{_}) in the output, to meet the requirements of the
26475 Recutils format. The following example shows how to print the account
26476 fingerprints for all accounts operating in the rendezvous point mode:
26479 # herd list-account-details jami | \
26480 recsel -p Account.username -e 'Account.rendezVous ~ "true"'
26481 Account_username: f3345f2775ddfe07a4b0d95daea111d15fbc1199
26484 The remaining actions should be self-explanatory.
26486 The complete set of available configuration options is detailed below.
26488 @c TODO: Ideally, the following fragments would be auto-generated at
26489 @c build time, so that they needn't be manually duplicated.
26490 @c Auto-generated via (configuration->documentation 'jami-configuration)
26491 @deftp {Data Type} jami-configuration
26492 Available @code{jami-configuration} fields are:
26495 @item @code{libjami} (default: @code{libjami}) (type: package)
26496 The Jami daemon package to use.
26498 @item @code{dbus} (default: @code{dbus-for-jami}) (type: package)
26499 The D-Bus package to use to start the required D-Bus session.
26501 @item @code{nss-certs} (default: @code{nss-certs}) (type: package)
26502 The nss-certs package to use to provide TLS certificates.
26504 @item @code{enable-logging?} (default: @code{#t}) (type: boolean)
26505 Whether to enable logging to syslog.
26507 @item @code{debug?} (default: @code{#f}) (type: boolean)
26508 Whether to enable debug level messages.
26510 @item @code{auto-answer?} (default: @code{#f}) (type: boolean)
26511 Whether to force automatic answer to incoming calls.
26513 @item @code{accounts} (type: maybe-jami-account-list)
26514 A list of Jami accounts to be (re-)provisioned every time the Jami
26515 daemon service starts. When providing this field, the account
26516 directories under @file{/var/lib/jami/} are recreated every time the
26517 service starts, ensuring a consistent state.
26523 @c Auto-generated via (configuration->documentation 'jami-account)
26524 @deftp {Data Type} jami-account
26525 Available @code{jami-account} fields are:
26528 @item @code{archive} (type: string-or-computed-file)
26529 The account archive (backup) file name of the account. This is used to
26530 provision the account when the service starts. The account archive
26531 should @emph{not} be encrypted. It is highly recommended to make it
26532 readable only to the @samp{root} user (i.e., not in the store), to guard
26533 against leaking the secret key material of the Jami account it contains.
26535 @item @code{allowed-contacts} (type: maybe-account-fingerprint-list)
26536 The list of allowed contacts for the account, entered as their 40
26537 characters long fingerprint. Messages or calls from accounts not in
26538 that list will be rejected. When left specified, the configuration of
26539 the account archive is used as-is with respect to contacts and public
26540 inbound calls/messaging allowance, which typically defaults to allow any
26541 contact to communicate with the account.
26543 @item @code{moderators} (type: maybe-account-fingerprint-list)
26544 The list of contacts that should have moderation privileges (to ban,
26545 mute, etc. other users) in rendezvous conferences, entered as their 40
26546 characters long fingerprint. When left unspecified, the configuration
26547 of the account archive is used as-is with respect to moderation, which
26548 typically defaults to allow anyone to moderate.
26550 @item @code{rendezvous-point?} (type: maybe-boolean)
26551 Whether the account should operate in the rendezvous mode. In this
26552 mode, all the incoming audio/video calls are mixed into a conference.
26553 When left unspecified, the value from the account archive prevails.
26555 @item @code{peer-discovery?} (type: maybe-boolean)
26556 Whether peer discovery should be enabled. Peer discovery is used to
26557 discover other OpenDHT nodes on the local network, which can be useful
26558 to maintain communication between devices on such network even when the
26559 connection to the the Internet has been lost. When left unspecified,
26560 the value from the account archive prevails.
26562 @item @code{bootstrap-hostnames} (type: maybe-string-list)
26563 A list of hostnames or IPs pointing to OpenDHT nodes, that should be
26564 used to initially join the OpenDHT network. When left unspecified, the
26565 value from the account archive prevails.
26567 @item @code{name-server-uri} (type: maybe-string)
26568 The URI of the name server to use, that can be used to retrieve the
26569 account fingerprint for a registered username.
26575 @subsubheading Mumble server
26579 @cindex VoIP server
26580 This section describes how to set up and run a
26581 @uref{https://mumble.info, Mumble} server (formerly known as Murmur).
26583 @deftp {Data Type} mumble-server-configuration
26584 The service type for the Mumble server. An example configuration can
26588 (service mumble-server-service-type
26589 (mumble-server-configuration
26591 "Welcome to this Mumble server running on Guix!")
26592 (cert-required? #t) ;disallow text password logins
26593 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
26594 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
26597 After reconfiguring your system, you can manually set the mumble-server
26599 password with the command that is printed during the activation phase.
26601 It is recommended to register a normal Mumble user account
26602 and grant it admin or moderator rights.
26603 You can use the @code{mumble} client to
26604 login as new normal user, register yourself, and log out.
26605 For the next step login with the name @code{SuperUser} use
26606 the @code{SuperUser} password that you set previously,
26607 and grant your newly registered mumble user administrator or moderator
26608 rights and create some channels.
26610 Available @code{mumble-server-configuration} fields are:
26613 @item @code{package} (default: @code{mumble})
26614 Package that contains @code{bin/mumble-server}.
26616 @item @code{user} (default: @code{"mumble-server"})
26617 User who will run the Mumble-Server server.
26619 @item @code{group} (default: @code{"mumble-server"})
26620 Group of the user who will run the mumble-server server.
26622 @item @code{port} (default: @code{64738})
26623 Port on which the server will listen.
26625 @item @code{welcome-text} (default: @code{""})
26626 Welcome text sent to clients when they connect.
26628 @item @code{server-password} (default: @code{""})
26629 Password the clients have to enter in order to connect.
26631 @item @code{max-users} (default: @code{100})
26632 Maximum of users that can be connected to the server at once.
26634 @item @code{max-user-bandwidth} (default: @code{#f})
26635 Maximum voice traffic a user can send per second.
26637 @item @code{database-file} (default: @code{"/var/lib/mumble-server/db.sqlite"})
26638 File name of the sqlite database.
26639 The service's user will become the owner of the directory.
26641 @item @code{log-file} (default: @code{"/var/log/mumble-server/mumble-server.log"})
26642 File name of the log file.
26643 The service's user will become the owner of the directory.
26645 @item @code{autoban-attempts} (default: @code{10})
26646 Maximum number of logins a user can make in @code{autoban-timeframe}
26647 without getting auto banned for @code{autoban-time}.
26649 @item @code{autoban-timeframe} (default: @code{120})
26650 Timeframe for autoban in seconds.
26652 @item @code{autoban-time} (default: @code{300})
26653 Amount of time in seconds for which a client gets banned
26654 when violating the autoban limits.
26656 @item @code{opus-threshold} (default: @code{100})
26657 Percentage of clients that need to support opus
26658 before switching over to opus audio codec.
26660 @item @code{channel-nesting-limit} (default: @code{10})
26661 How deep channels can be nested at maximum.
26663 @item @code{channelname-regex} (default: @code{#f})
26664 A string in form of a Qt regular expression that channel names must conform to.
26666 @item @code{username-regex} (default: @code{#f})
26667 A string in form of a Qt regular expression that user names must conform to.
26669 @item @code{text-message-length} (default: @code{5000})
26670 Maximum size in bytes that a user can send in one text chat message.
26672 @item @code{image-message-length} (default: @code{(* 128 1024)})
26673 Maximum size in bytes that a user can send in one image message.
26675 @item @code{cert-required?} (default: @code{#f})
26676 If it is set to @code{#t} clients that use weak password authentication
26677 will not be accepted. Users must have completed the certificate wizard to join.
26679 @item @code{remember-channel?} (default: @code{#f})
26680 Should mumble-server remember the last channel each user was in when
26681 they disconnected and put them into the remembered channel when they
26684 @item @code{allow-html?} (default: @code{#f})
26685 Should html be allowed in text messages, user comments, and channel descriptions.
26687 @item @code{allow-ping?} (default: @code{#f})
26688 Setting to true exposes the current user count, the maximum user count, and
26689 the server's maximum bandwidth per client to unauthenticated users. In the
26690 Mumble client, this information is shown in the Connect dialog.
26692 Disabling this setting will prevent public listing of the server.
26694 @item @code{bonjour?} (default: @code{#f})
26695 Should the server advertise itself in the local network through the bonjour protocol.
26697 @item @code{send-version?} (default: @code{#f})
26698 Should the mumble-server server version be exposed in ping requests.
26700 @item @code{log-days} (default: @code{31})
26701 Mumble also stores logs in the database, which are accessible via RPC.
26702 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
26703 or -1 to disable logging to the database.
26705 @item @code{obfuscate-ips?} (default: @code{#t})
26706 Should logged ips be obfuscated to protect the privacy of users.
26708 @item @code{ssl-cert} (default: @code{#f})
26709 File name of the SSL/TLS certificate used for encrypted connections.
26712 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
26714 @item @code{ssl-key} (default: @code{#f})
26715 Filepath to the ssl private key used for encrypted connections.
26717 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
26720 @item @code{ssl-dh-params} (default: @code{#f})
26721 File name of a PEM-encoded file with Diffie-Hellman parameters
26722 for the SSL/TLS encryption. Alternatively you set it to
26723 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
26724 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
26726 @item @code{ssl-ciphers} (default: @code{#f})
26727 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
26730 This option is specified using
26731 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
26732 OpenSSL cipher list notation}.
26734 It is recommended that you try your cipher string using
26735 'openssl ciphers <string>' before setting it here, to get a feel for
26736 which cipher suites you will get.
26737 After setting this option, it is recommend that you inspect your Mumble
26738 server log to ensure that Mumble is using the cipher suites that you
26742 Changing this option may impact the backwards compatibility of your
26743 Mumble-Server server, and can remove the ability for older Mumble clients to be able to connect to it.
26746 @item @code{public-registration} (default: @code{#f})
26747 Must be a @code{<mumble-server-public-registration-configuration>}
26748 record or @code{#f}.
26750 You can optionally register your server in the public server list that the
26751 @code{mumble} client shows on startup.
26752 You cannot register your server if you have set a @code{server-password},
26753 or set @code{allow-ping} to @code{#f}.
26755 It might take a few hours until it shows up in the public list.
26757 @item @code{file} (default: @code{#f})
26758 Optional alternative override for this configuration.
26762 @deftp {Data Type} mumble-server-public-registration-configuration
26763 Configuration for public registration of a mumble-server service.
26767 This is a display name for your server. Not to be confused with the hostname.
26769 @item @code{password}
26770 A password to identify your registration.
26771 Subsequent updates will need the same password. Don't lose your password.
26774 This should be a @code{http://} or @code{https://} link to your web
26777 @item @code{hostname} (default: @code{#f})
26778 By default your server will be listed by its IP address.
26779 If it is set your server will be linked by this host name instead.
26783 @quotation Deprecation notice
26784 Due to historical reasons, all of the above @code{mumble-server-}
26785 procedures are also exported with the @code{murmur-} prefix.
26786 It is recommended that you switch to using @code{mumble-server-}
26790 @node File-Sharing Services
26791 @subsection File-Sharing Services
26793 The @code{(gnu services file-sharing)} module provides services that
26794 assist with transferring files over peer-to-peer file-sharing networks.
26796 @subsubheading Transmission Daemon Service
26798 @uref{https://transmissionbt.com/, Transmission} is a flexible
26799 BitTorrent client that offers a variety of graphical and command-line
26800 interfaces. A @code{transmission-daemon-service-type} service provides
26801 Transmission's headless variant, @command{transmission-daemon}, as a
26802 system service, allowing users to share files via BitTorrent even when
26803 they are not logged in.
26805 @deffn {Scheme Variable} transmission-daemon-service-type
26806 The service type for the Transmission Daemon BitTorrent client. Its
26807 value must be a @code{transmission-daemon-configuration} object as in
26811 (service transmission-daemon-service-type
26812 (transmission-daemon-configuration
26813 ;; Restrict access to the RPC ("control") interface
26814 (rpc-authentication-required? #t)
26815 (rpc-username "transmission")
26817 (transmission-password-hash
26818 "transmission" ; desired password
26819 "uKd1uMs9")) ; arbitrary salt value
26821 ;; Accept requests from this and other hosts on the
26823 (rpc-whitelist-enabled? #t)
26824 (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
26826 ;; Limit bandwidth use during work hours
26827 (alt-speed-down (* 1024 2)) ; 2 MB/s
26828 (alt-speed-up 512) ; 512 kB/s
26830 (alt-speed-time-enabled? #t)
26831 (alt-speed-time-day 'weekdays)
26832 (alt-speed-time-begin
26833 (+ (* 60 8) 30)) ; 8:30 am
26834 (alt-speed-time-end
26835 (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
26839 Once the service is started, users can interact with the daemon through
26840 its Web interface (at @code{http://localhost:9091/}) or by using the
26841 @command{transmission-remote} command-line tool, available in the
26842 @code{transmission} package. (Emacs users may want to also consider the
26843 @code{emacs-transmission} package.) Both communicate with the daemon
26844 through its remote procedure call (RPC) interface, which by default is
26845 available to all users on the system; you may wish to change this by
26846 assigning values to the @code{rpc-authentication-required?},
26847 @code{rpc-username} and @code{rpc-password} settings, as shown in the
26848 example above and documented further below.
26850 The value for @code{rpc-password} must be a password hash of the type
26851 generated and used by Transmission clients. This can be copied verbatim
26852 from an existing @file{settings.json} file, if another Transmission
26853 client is already being used. Otherwise, the
26854 @code{transmission-password-hash} and @code{transmission-random-salt}
26855 procedures provided by this module can be used to obtain a suitable hash
26858 @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
26859 Returns a string containing the result of hashing @var{password}
26860 together with @var{salt}, in the format recognized by Transmission
26861 clients for their @code{rpc-password} configuration setting.
26863 @var{salt} must be an eight-character string. The
26864 @code{transmission-random-salt} procedure can be used to generate a
26865 suitable salt value at random.
26868 @deffn {Scheme Procedure} transmission-random-salt
26869 Returns a string containing a random, eight-character salt value of the
26870 type generated and used by Transmission clients, suitable for passing to
26871 the @code{transmission-password-hash} procedure.
26874 These procedures are accessible from within a Guile REPL started with
26875 the @command{guix repl} command (@pxref{Invoking guix repl}). This is
26876 useful for obtaining a random salt value to provide as the second
26877 parameter to `transmission-password-hash`, as in this example session:
26881 scheme@@(guix-user)> ,use (gnu services file-sharing)
26882 scheme@@(guix-user)> (transmission-random-salt)
26886 Alternatively, a complete password hash can generated in a single step:
26889 scheme@@(guix-user)> (transmission-password-hash "transmission"
26890 (transmission-random-salt))
26891 $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
26894 The resulting string can be used as-is for the value of
26895 @code{rpc-password}, allowing the password to be kept hidden even in the
26896 operating-system configuration.
26898 Torrent files downloaded by the daemon are directly accessible only to
26899 users in the ``transmission'' user group, who receive read-only access
26900 to the directory specified by the @code{download-dir} configuration
26901 setting (and also the directory specified by @code{incomplete-dir}, if
26902 @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
26903 moved to another directory or deleted altogether using
26904 @command{transmission-remote} with its @code{--move} and
26905 @code{--remove-and-delete} options.
26907 If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
26908 the ``transmission'' group are able also to place @file{.torrent} files
26909 in the directory specified by @code{watch-dir} to have the corresponding
26910 torrents added by the daemon. (The @code{trash-original-torrent-files?}
26911 setting controls whether the daemon deletes these files after processing
26914 Some of the daemon's configuration settings can be changed temporarily
26915 by @command{transmission-remote} and similar tools. To undo these
26916 changes, use the service's @code{reload} action to have the daemon
26917 reload its settings from disk:
26920 # herd reload transmission-daemon
26923 The full set of available configuration settings is defined by the
26924 @code{transmission-daemon-configuration} data type.
26926 @deftp {Data Type} transmission-daemon-configuration
26927 The data type representing configuration settings for Transmission
26928 Daemon. These correspond directly to the settings recognized by
26929 Transmission clients in their @file{settings.json} file.
26932 @c The following documentation was initially generated by
26933 @c (generate-transmission-daemon-documentation) in (gnu services
26934 @c file-sharing). Manually maintained documentation is better, so we
26935 @c shouldn't hesitate to edit below as needed. However if the change
26936 @c you want to make to this documentation can be done in an automated
26937 @c way, it's probably easier to change (generate-documentation) than to
26938 @c make it below and have to deal with the churn as Transmission Daemon
26941 @c %start of fragment
26943 Available @code{transmission-daemon-configuration} fields are:
26945 @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
26946 The Transmission package to use.
26950 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
26951 The period, in seconds, to wait when stopping the service for
26952 @command{transmission-daemon} to exit before killing its process. This
26953 allows the daemon time to complete its housekeeping and send a final
26954 update to trackers as it shuts down. On slow hosts, or hosts with a
26955 slow network connection, this value may need to be increased.
26957 Defaults to @samp{10}.
26961 @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
26962 The directory to which torrent files are downloaded.
26964 Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
26968 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
26969 If @code{#t}, files will be held in @code{incomplete-dir} while their
26970 torrent is being downloaded, then moved to @code{download-dir} once the
26971 torrent is complete. Otherwise, files for all torrents (including those
26972 still being downloaded) will be placed in @code{download-dir}.
26974 Defaults to @samp{#f}.
26978 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
26979 The directory in which files from incompletely downloaded torrents will
26980 be held when @code{incomplete-dir-enabled?} is @code{#t}.
26982 Defaults to @samp{disabled}.
26986 @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
26987 The file mode creation mask used for downloaded files. (See the
26988 @command{umask} man page for more information.)
26990 Defaults to @samp{18}.
26994 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
26995 When @code{#t}, ``.part'' is appended to the name of partially
26998 Defaults to @samp{#t}.
27002 @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
27003 The mode by which space should be preallocated for downloaded files, one
27004 of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
27005 Specifying @code{full} will minimize disk fragmentation at a cost to
27006 file-creation speed.
27008 Defaults to @samp{fast}.
27012 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
27013 If @code{#t}, the directory specified by @code{watch-dir} will be
27014 watched for new @file{.torrent} files and the torrents they describe
27015 added automatically (and the original files removed, if
27016 @code{trash-original-torrent-files?} is @code{#t}).
27018 Defaults to @samp{#f}.
27022 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
27023 The directory to be watched for @file{.torrent} files indicating new
27024 torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
27026 Defaults to @samp{disabled}.
27030 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
27031 When @code{#t}, @file{.torrent} files will be deleted from the watch
27032 directory once their torrent has been added (see
27033 @code{watch-directory-enabled?}).
27035 Defaults to @samp{#f}.
27039 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
27040 When @code{#t}, the daemon's download speed will be limited to the rate
27041 specified by @code{speed-limit-down}.
27043 Defaults to @samp{#f}.
27047 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
27048 The default global-maximum download speed, in kilobytes per second.
27050 Defaults to @samp{100}.
27054 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
27055 When @code{#t}, the daemon's upload speed will be limited to the rate
27056 specified by @code{speed-limit-up}.
27058 Defaults to @samp{#f}.
27062 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
27063 The default global-maximum upload speed, in kilobytes per second.
27065 Defaults to @samp{100}.
27069 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
27070 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
27071 @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
27072 @code{speed-limit-up}, if they are enabled) to constrain the daemon's
27073 bandwidth usage. This can be scheduled to occur automatically at
27074 certain times during the week; see @code{alt-speed-time-enabled?}.
27076 Defaults to @samp{#f}.
27080 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
27081 The alternate global-maximum download speed, in kilobytes per second.
27083 Defaults to @samp{50}.
27087 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
27088 The alternate global-maximum upload speed, in kilobytes per second.
27090 Defaults to @samp{50}.
27094 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
27095 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
27096 @code{alt-speed-up} will be enabled automatically during the periods
27097 specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
27098 @code{alt-time-speed-end}.
27100 Defaults to @samp{#f}.
27104 @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
27105 The days of the week on which the alternate-speed schedule should be
27106 used, specified either as a list of days (@code{sunday}, @code{monday},
27107 and so on) or using one of the symbols @code{weekdays}, @code{weekends}
27110 Defaults to @samp{all}.
27114 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
27115 The time of day at which to enable the alternate speed limits, expressed
27116 as a number of minutes since midnight.
27118 Defaults to @samp{540}.
27122 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
27123 The time of day at which to disable the alternate speed limits,
27124 expressed as a number of minutes since midnight.
27126 Defaults to @samp{1020}.
27130 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
27131 The IP address at which to listen for peer connections, or ``0.0.0.0''
27132 to listen at all available IP addresses.
27134 Defaults to @samp{"0.0.0.0"}.
27138 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
27139 The IPv6 address at which to listen for peer connections, or ``::'' to
27140 listen at all available IPv6 addresses.
27142 Defaults to @samp{"::"}.
27146 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
27147 If @code{#t}, when the daemon starts it will select a port at random on
27148 which to listen for peer connections, from the range specified
27149 (inclusively) by @code{peer-port-random-low} and
27150 @code{peer-port-random-high}. Otherwise, it listens on the port
27151 specified by @code{peer-port}.
27153 Defaults to @samp{#f}.
27157 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
27158 The lowest selectable port number when @code{peer-port-random-on-start?}
27161 Defaults to @samp{49152}.
27165 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
27166 The highest selectable port number when @code{peer-port-random-on-start}
27169 Defaults to @samp{65535}.
27173 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
27174 The port on which to listen for peer connections when
27175 @code{peer-port-random-on-start?} is @code{#f}.
27177 Defaults to @samp{51413}.
27181 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
27182 If @code{#t}, the daemon will attempt to configure port-forwarding on an
27183 upstream gateway automatically using @acronym{UPnP} and
27186 Defaults to @samp{#t}.
27190 @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
27191 The encryption preference for peer connections, one of
27192 @code{prefer-unencrypted-connections},
27193 @code{prefer-encrypted-connections} or
27194 @code{require-encrypted-connections}.
27196 Defaults to @samp{prefer-encrypted-connections}.
27200 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
27201 The TCP congestion-control algorithm to use for peer connections,
27202 specified using a string recognized by the operating system in calls to
27203 @code{setsockopt}. When left unspecified, the operating-system default
27206 Note that on GNU/Linux systems, the kernel must be configured to allow
27207 processes to use a congestion-control algorithm not in the default set;
27208 otherwise, it will deny these requests with ``Operation not permitted''.
27209 To see which algorithms are available on your system and which are
27210 currently permitted for use, look at the contents of the files
27211 @file{tcp_available_congestion_control} and
27212 @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
27215 As an example, to have Transmission Daemon use
27216 @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
27217 congestion-control algorithm}, you'll need to modify your kernel
27218 configuration to build in support for the algorithm, then update your
27219 operating-system configuration to allow its use by adding a
27220 @code{sysctl-service-type} service (or updating the existing one's
27221 configuration) with lines like the following:
27224 (service sysctl-service-type
27225 (sysctl-configuration
27227 ("net.ipv4.tcp_allowed_congestion_control" .
27228 "reno cubic lp"))))
27231 The Transmission Daemon configuration can then be updated with
27234 (peer-congestion-algorithm "lp")
27237 and the system reconfigured to have the changes take effect.
27239 Defaults to @samp{disabled}.
27243 @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
27244 The type of service to request in outgoing @acronym{TCP} packets, one of
27245 @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
27246 @code{reliability}.
27248 Defaults to @samp{default}.
27252 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
27253 The global limit on the number of connected peers.
27255 Defaults to @samp{200}.
27259 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
27260 The per-torrent limit on the number of connected peers.
27262 Defaults to @samp{50}.
27266 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
27267 The maximum number of peers to which the daemon will upload data
27268 simultaneously for each torrent.
27270 Defaults to @samp{14}.
27274 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
27275 The maximum lifespan, in hours, of the peer ID associated with each
27276 public torrent before it is regenerated.
27278 Defaults to @samp{6}.
27282 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
27283 When @code{#t}, the daemon will ignore peers mentioned in the blocklist
27284 it has most recently downloaded from @code{blocklist-url}.
27286 Defaults to @samp{#f}.
27290 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
27291 The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
27292 @file{.dat} format) to be periodically downloaded and applied when
27293 @code{blocklist-enabled?} is @code{#t}.
27295 Defaults to @samp{disabled}.
27299 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
27300 If @code{#t}, the daemon will be limited to downloading at most
27301 @code{download-queue-size} non-stalled torrents simultaneously.
27303 Defaults to @samp{#t}.
27307 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
27308 The size of the daemon's download queue, which limits the number of
27309 non-stalled torrents it will download at any one time when
27310 @code{download-queue-enabled?} is @code{#t}.
27312 Defaults to @samp{5}.
27316 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
27317 If @code{#t}, the daemon will be limited to seeding at most
27318 @code{seed-queue-size} non-stalled torrents simultaneously.
27320 Defaults to @samp{#f}.
27324 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
27325 The size of the daemon's seed queue, which limits the number of
27326 non-stalled torrents it will seed at any one time when
27327 @code{seed-queue-enabled?} is @code{#t}.
27329 Defaults to @samp{10}.
27333 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
27334 When @code{#t}, the daemon will consider torrents for which it has not
27335 shared data in the past @code{queue-stalled-minutes} minutes to be
27336 stalled and not count them against its @code{download-queue-size} and
27337 @code{seed-queue-size} limits.
27339 Defaults to @samp{#t}.
27343 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
27344 The maximum period, in minutes, a torrent may be idle before it is
27345 considered to be stalled, when @code{queue-stalled-enabled?} is
27348 Defaults to @samp{30}.
27352 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
27353 When @code{#t}, a torrent being seeded will automatically be paused once
27354 it reaches the ratio specified by @code{ratio-limit}.
27356 Defaults to @samp{#f}.
27360 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
27361 The ratio at which a torrent being seeded will be paused, when
27362 @code{ratio-limit-enabled?} is @code{#t}.
27364 Defaults to @samp{2.0}.
27368 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
27369 When @code{#t}, a torrent being seeded will automatically be paused once
27370 it has been idle for @code{idle-seeding-limit} minutes.
27372 Defaults to @samp{#f}.
27376 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
27377 The maximum period, in minutes, a torrent being seeded may be idle
27378 before it is paused, when @code{idle-seeding-limit-enabled?} is
27381 Defaults to @samp{30}.
27385 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
27386 Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
27387 hash table (@acronym{DHT}) protocol}, which supports the use of
27388 trackerless torrents.
27390 Defaults to @samp{#t}.
27394 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
27395 Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
27396 peer discovery} (@acronym{LPD}), which allows the discovery of peers on
27397 the local network and may reduce the amount of data sent over the public
27400 Defaults to @samp{#f}.
27404 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
27405 Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
27406 (@acronym{PEX}), which reduces the daemon's reliance on external
27407 trackers and may improve its performance.
27409 Defaults to @samp{#t}.
27413 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
27414 Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
27415 transport protocol} (@acronym{uTP}), which aims to reduce the impact of
27416 BitTorrent traffic on other users of the local network while maintaining
27417 full utilization of the available bandwidth.
27419 Defaults to @samp{#t}.
27423 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
27424 If @code{#t}, enable the remote procedure call (@acronym{RPC})
27425 interface, which allows remote control of the daemon via its Web
27426 interface, the @command{transmission-remote} command-line client, and
27429 Defaults to @samp{#t}.
27433 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
27434 The IP address at which to listen for @acronym{RPC} connections, or
27435 ``0.0.0.0'' to listen at all available IP addresses.
27437 Defaults to @samp{"0.0.0.0"}.
27441 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
27442 The port on which to listen for @acronym{RPC} connections.
27444 Defaults to @samp{9091}.
27448 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
27449 The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
27451 Defaults to @samp{"/transmission/"}.
27455 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
27456 When @code{#t}, clients must authenticate (see @code{rpc-username} and
27457 @code{rpc-password}) when using the @acronym{RPC} interface. Note this
27458 has the side effect of disabling host-name whitelisting (see
27459 @code{rpc-host-whitelist-enabled?}.
27461 Defaults to @samp{#f}.
27465 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
27466 The username required by clients to access the @acronym{RPC} interface
27467 when @code{rpc-authentication-required?} is @code{#t}.
27469 Defaults to @samp{disabled}.
27473 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
27474 The password required by clients to access the @acronym{RPC} interface
27475 when @code{rpc-authentication-required?} is @code{#t}. This must be
27476 specified using a password hash in the format recognized by Transmission
27477 clients, either copied from an existing @file{settings.json} file or
27478 generated using the @code{transmission-password-hash} procedure.
27480 Defaults to @samp{disabled}.
27484 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
27485 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27486 originate from an address specified in @code{rpc-whitelist}.
27488 Defaults to @samp{#t}.
27492 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
27493 The list of IP and IPv6 addresses from which @acronym{RPC} requests will
27494 be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
27495 may be specified using @samp{*}.
27497 Defaults to @samp{("127.0.0.1" "::1")}.
27501 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
27502 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27503 are addressed to a host named in @code{rpc-host-whitelist}. Note that
27504 requests to ``localhost'' or ``localhost.'', or to a numeric address,
27505 are always accepted regardless of these settings.
27507 Note also this functionality is disabled when
27508 @code{rpc-authentication-required?} is @code{#t}.
27510 Defaults to @samp{#t}.
27514 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
27515 The list of host names recognized by the @acronym{RPC} server when
27516 @code{rpc-host-whitelist-enabled?} is @code{#t}.
27518 Defaults to @samp{()}.
27522 @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
27523 The minimum severity level of messages to be logged (to
27524 @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
27525 logging), @code{error}, @code{info} and @code{debug}.
27527 Defaults to @samp{info}.
27531 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
27532 When @code{#t}, torrents are started as soon as they are added;
27533 otherwise, they are added in ``paused'' state.
27535 Defaults to @samp{#t}.
27539 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
27540 When @code{#t}, the script specified by
27541 @code{script-torrent-done-filename} will be invoked each time a torrent
27544 Defaults to @samp{#f}.
27548 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
27549 A file name or file-like object specifying a script to run each time a
27550 torrent completes, when @code{script-torrent-done-enabled?} is
27553 Defaults to @samp{disabled}.
27557 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
27558 When @code{#t}, the daemon will scrape trackers for a torrent even when
27559 the torrent is paused.
27561 Defaults to @samp{#t}.
27565 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
27566 The amount of memory, in megabytes, to allocate for the daemon's
27567 in-memory cache. A larger value may increase performance by reducing
27568 the frequency of disk I/O.
27570 Defaults to @samp{4}.
27574 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
27575 When @code{#t}, the daemon will try to improve I/O performance by
27576 hinting to the operating system which data is likely to be read next
27577 from disk to satisfy requests from peers.
27579 Defaults to @samp{#t}.
27584 @c %end of fragment
27588 @node Monitoring Services
27589 @subsection Monitoring Services
27591 @subsubheading Tailon Service
27593 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
27594 viewing and searching log files.
27596 The following example will configure the service with default values.
27597 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
27600 (service tailon-service-type)
27603 The following example customises more of the Tailon configuration,
27604 adding @command{sed} to the list of allowed commands.
27607 (service tailon-service-type
27608 (tailon-configuration
27610 (tailon-configuration-file
27611 (allowed-commands '("tail" "grep" "awk" "sed"))))))
27615 @deftp {Data Type} tailon-configuration
27616 Data type representing the configuration of Tailon.
27617 This type has the following parameters:
27620 @item @code{config-file} (default: @code{(tailon-configuration-file)})
27621 The configuration file to use for Tailon. This can be set to a
27622 @dfn{tailon-configuration-file} record value, or any gexp
27623 (@pxref{G-Expressions}).
27625 For example, to instead use a local file, the @code{local-file} function
27629 (service tailon-service-type
27630 (tailon-configuration
27631 (config-file (local-file "./my-tailon.conf"))))
27634 @item @code{package} (default: @code{tailon})
27635 The tailon package to use.
27640 @deftp {Data Type} tailon-configuration-file
27641 Data type representing the configuration options for Tailon.
27642 This type has the following parameters:
27645 @item @code{files} (default: @code{(list "/var/log")})
27646 List of files to display. The list can include strings for a single file
27647 or directory, or a list, where the first item is the name of a
27648 subsection, and the remaining items are the files or directories in that
27651 @item @code{bind} (default: @code{"localhost:8080"})
27652 Address and port to which Tailon should bind on.
27654 @item @code{relative-root} (default: @code{#f})
27655 URL path to use for Tailon, set to @code{#f} to not use a path.
27657 @item @code{allow-transfers?} (default: @code{#t})
27658 Allow downloading the log files in the web interface.
27660 @item @code{follow-names?} (default: @code{#t})
27661 Allow tailing of not-yet existent files.
27663 @item @code{tail-lines} (default: @code{200})
27664 Number of lines to read initially from each file.
27666 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
27667 Commands to allow running. By default, @code{sed} is disabled.
27669 @item @code{debug?} (default: @code{#f})
27670 Set @code{debug?} to @code{#t} to show debug messages.
27672 @item @code{wrap-lines} (default: @code{#t})
27673 Initial line wrapping state in the web interface. Set to @code{#t} to
27674 initially wrap lines (the default), or to @code{#f} to initially not
27677 @item @code{http-auth} (default: @code{#f})
27678 HTTP authentication type to use. Set to @code{#f} to disable
27679 authentication (the default). Supported values are @code{"digest"} or
27682 @item @code{users} (default: @code{#f})
27683 If HTTP authentication is enabled (see @code{http-auth}), access will be
27684 restricted to the credentials provided here. To configure users, use a
27685 list of pairs, where the first element of the pair is the username, and
27686 the 2nd element of the pair is the password.
27689 (tailon-configuration-file
27690 (http-auth "basic")
27691 (users '(("user1" . "password1")
27692 ("user2" . "password2"))))
27699 @subsubheading Darkstat Service
27701 Darkstat is a packet sniffer that captures network traffic, calculates
27702 statistics about usage, and serves reports over HTTP.
27704 @defvar {Scheme Variable} darkstat-service-type
27705 This is the service type for the
27706 @uref{https://unix4lyfe.org/darkstat/, darkstat}
27707 service, its value must be a @code{darkstat-configuration} record as in
27711 (service darkstat-service-type
27712 (darkstat-configuration
27713 (interface "eno1")))
27717 @deftp {Data Type} darkstat-configuration
27718 Data type representing the configuration of @command{darkstat}.
27721 @item @code{package} (default: @code{darkstat})
27722 The darkstat package to use.
27724 @item @code{interface}
27725 Capture traffic on the specified network interface.
27727 @item @code{port} (default: @code{"667"})
27728 Bind the web interface to the specified port.
27730 @item @code{bind-address} (default: @code{"127.0.0.1"})
27731 Bind the web interface to the specified address.
27733 @item @code{base} (default: @code{"/"})
27734 Specify the path of the base URL@. This can be useful if
27735 @command{darkstat} is accessed via a reverse proxy.
27740 @anchor{prometheus-node-exporter}
27741 @subsubheading Prometheus Node Exporter Service
27742 @cindex prometheus-node-exporter
27744 The Prometheus ``node exporter'' makes hardware and operating system statistics
27745 provided by the Linux kernel available for the Prometheus monitoring system.
27746 This service should be deployed on all physical nodes and virtual machines,
27747 where monitoring these statistics is desirable.
27749 @defvar {Scheme variable} prometheus-node-exporter-service-type
27750 This is the service type for the
27751 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
27752 service, its value must be a @code{prometheus-node-exporter-configuration}.
27755 (service prometheus-node-exporter-service-type)
27759 @deftp {Data Type} prometheus-node-exporter-configuration
27760 Data type representing the configuration of @command{node_exporter}.
27763 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
27764 The prometheus-node-exporter package to use.
27766 @item @code{web-listen-address} (default: @code{":9100"})
27767 Bind the web interface to the specified address.
27769 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
27770 This directory can be used to export metrics specific to this machine.
27771 Files containing metrics in the text format, with the filename ending in
27772 @code{.prom} should be placed in this directory.
27774 @item @code{extra-options} (default: @code{'()})
27775 Extra options to pass to the Prometheus node exporter.
27780 @subsubheading Zabbix server
27781 @cindex zabbix zabbix-server
27782 Zabbix is a high performance monitoring system that can collect data from a
27783 variety of sources and provide the results in a web-based interface. Alerting
27784 and reporting is built-in, as well as @dfn{templates} for common operating
27785 system metrics such as network utilization, CPU load, and disk space consumption.
27787 This service provides the central Zabbix monitoring service; you also need
27788 @ref{zabbix-front-end,@code{zabbix-front-end-service-type}} to configure Zabbix
27789 and display results, and optionally @ref{zabbix-agent,
27790 @code{zabbix-agent-service-type}} on machines that should be monitored (other
27791 data sources are supported, such as @ref{prometheus-node-exporter,
27792 Prometheus Node Exporter}).
27794 @defvar {Scheme variable} zabbix-server-service-type
27795 This is the service type for the Zabbix server service. Its value must be a
27796 @code{zabbix-server-configuration} record, shown below.
27799 @c %start of fragment
27801 @deftp {Data Type} zabbix-server-configuration
27802 Available @code{zabbix-server-configuration} fields are:
27805 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27806 The zabbix-server package.
27808 @item @code{user} (default: @code{"zabbix"}) (type: string)
27809 User who will run the Zabbix server.
27811 @item @code{group} (default: @code{"zabbix"}) (type: group)
27812 Group who will run the Zabbix server.
27814 @item @code{db-host} (default: @code{"127.0.0.1"}) (type: string)
27815 Database host name.
27817 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27820 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27823 @item @code{db-password} (default: @code{""}) (type: string)
27824 Database password. Please, use @code{include-files} with
27825 @code{DBPassword=SECRET} inside a specified file instead.
27827 @item @code{db-port} (default: @code{5432}) (type: number)
27830 @item @code{log-type} (default: @code{""}) (type: string)
27831 Specifies where log messages are written to:
27835 @item @code{system} - syslog.
27837 @item @code{file} - file specified with @code{log-file} parameter.
27839 @item @code{console} - standard output.
27843 @item @code{log-file} (default: @code{"/var/log/zabbix/server.log"}) (type: string)
27844 Log file name for @code{log-type} @code{file} parameter.
27846 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_server.pid"}) (type: string)
27849 @item @code{ssl-ca-location} (default: @code{"/etc/ssl/certs/ca-certificates.crt"}) (type: string)
27850 The location of certificate authority (CA) files for SSL server
27851 certificate verification.
27853 @item @code{ssl-cert-location} (default: @code{"/etc/ssl/certs"}) (type: string)
27854 Location of SSL client certificates.
27856 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27857 Extra options will be appended to Zabbix server configuration file.
27859 @item @code{include-files} (default: @code{()}) (type: include-files)
27860 You may include individual files or all files in a directory in the
27861 configuration file.
27868 @c %end of fragment
27870 @anchor{zabbix-agent}
27871 @subsubheading Zabbix agent
27872 @cindex zabbix zabbix-agent
27874 The Zabbix agent gathers information about the running system for the Zabbix
27875 monitoring server. It has a variety of built-in checks, and can be extended
27877 @uref{https://www.zabbix.com/documentation/current/en/manual/config/items/userparameters,
27878 @dfn{user parameters}}.
27880 @defvar {Scheme variable} zabbix-agent-service-type
27881 This is the service type for the Zabbix agent service. Its value must be a
27882 @code{zabbix-agent-configuration} record, shown below.
27885 @c %start of fragment
27887 @deftp {Data Type} zabbix-agent-configuration
27888 Available @code{zabbix-agent-configuration} fields are:
27891 @item @code{zabbix-agent} (default: @code{zabbix-agentd}) (type: file-like)
27892 The zabbix-agent package.
27894 @item @code{user} (default: @code{"zabbix"}) (type: string)
27895 User who will run the Zabbix agent.
27897 @item @code{group} (default: @code{"zabbix"}) (type: group)
27898 Group who will run the Zabbix agent.
27900 @item @code{hostname} (default: @code{""}) (type: string)
27901 Unique, case sensitive hostname which is required for active checks and
27902 must match hostname as configured on the server.
27904 @item @code{log-type} (default: @code{""}) (type: string)
27905 Specifies where log messages are written to:
27909 @code{system} - syslog.
27911 @item @code{file} - file specified with
27912 @code{log-file} parameter.
27914 @item @code{console} - standard output.
27918 @item @code{log-file} (default: @code{"/var/log/zabbix/agent.log"}) (type: string)
27919 Log file name for @code{log-type} @code{file} parameter.
27921 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_agent.pid"}) (type: string)
27924 @item @code{server} (default: @code{("127.0.0.1")}) (type: list)
27925 List of IP addresses, optionally in CIDR notation, or hostnames of
27926 Zabbix servers and Zabbix proxies. Incoming connections will be
27927 accepted only from the hosts listed here.
27929 @item @code{server-active} (default: @code{("127.0.0.1")}) (type: list)
27930 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
27931 proxies for active checks. If port is not specified, default port is
27932 used. If this parameter is not specified, active checks are disabled.
27934 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27935 Extra options will be appended to Zabbix server configuration file.
27937 @item @code{include-files} (default: @code{()}) (type: include-files)
27938 You may include individual files or all files in a directory in the
27939 configuration file.
27946 @c %end of fragment
27948 @anchor{zabbix-front-end}
27949 @subsubheading Zabbix front-end
27950 @cindex zabbix zabbix-front-end
27952 The Zabbix front-end provides a web interface to Zabbix. It does not need
27953 to run on the same machine as the Zabbix server. This service works by
27954 extending the @ref{PHP-FPM} and @ref{NGINX} services with the configuration
27955 necessary for loading the Zabbix user interface.
27957 @defvar {Scheme variable} zabbix-front-end-service-type
27958 This is the service type for the Zabbix web frontend. Its value must be a
27959 @code{zabbix-front-end-configuration} record, shown below.
27962 @c %start of fragment
27964 @deftp {Data Type} zabbix-front-end-configuration
27965 Available @code{zabbix-front-end-configuration} fields are:
27968 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27969 The Zabbix server package to use.
27971 @item @code{nginx} (default: @code{()}) (type: list)
27972 List of @ref{nginx-server-configuration,@code{nginx-server-configuration}}
27973 blocks for the Zabbix front-end. When empty, a default that listens on
27976 @item @code{db-host} (default: @code{"localhost"}) (type: string)
27977 Database host name.
27979 @item @code{db-port} (default: @code{5432}) (type: number)
27982 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27985 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27988 @item @code{db-password} (default: @code{""}) (type: string)
27989 Database password. Please, use @code{db-secret-file} instead.
27991 @item @code{db-secret-file} (default: @code{""}) (type: string)
27992 Secret file which will be appended to @file{zabbix.conf.php} file. This
27993 file contains credentials for use by Zabbix front-end. You are expected
27994 to create it manually.
27996 @item @code{zabbix-host} (default: @code{"localhost"}) (type: string)
27997 Zabbix server hostname.
27999 @item @code{zabbix-port} (default: @code{10051}) (type: number)
28000 Zabbix server port.
28007 @c %end of fragment
28009 @node Kerberos Services
28010 @subsection Kerberos Services
28013 The @code{(gnu services kerberos)} module provides services relating to
28014 the authentication protocol @dfn{Kerberos}.
28016 @subsubheading Krb5 Service
28018 Programs using a Kerberos client library normally
28019 expect a configuration file in @file{/etc/krb5.conf}.
28020 This service generates such a file from a definition provided in the
28021 operating system declaration.
28022 It does not cause any daemon to be started.
28024 No ``keytab'' files are provided by this service---you must explicitly create them.
28025 This service is known to work with the MIT client library, @code{mit-krb5}.
28026 Other implementations have not been tested.
28028 @defvr {Scheme Variable} krb5-service-type
28029 A service type for Kerberos 5 clients.
28033 Here is an example of its use:
28035 (service krb5-service-type
28036 (krb5-configuration
28037 (default-realm "EXAMPLE.COM")
28038 (allow-weak-crypto? #t)
28041 (name "EXAMPLE.COM")
28042 (admin-server "groucho.example.com")
28043 (kdc "karl.example.com"))
28046 (admin-server "kerb-admin.argrx.edu")
28047 (kdc "keys.argrx.edu"))))))
28051 This example provides a Kerberos@tie{}5 client configuration which:
28053 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
28054 of which have distinct administration servers and key distribution centers;
28055 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
28056 specified by clients;
28057 @item Accepts services which only support encryption types known to be weak.
28060 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
28061 Only the most commonly used ones are described here.
28062 For a full list, and more detailed explanation of each, see the MIT
28063 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
28067 @deftp {Data Type} krb5-realm
28068 @cindex realm, kerberos
28071 This field is a string identifying the name of the realm.
28072 A common convention is to use the fully qualified DNS name of your organization,
28073 converted to upper case.
28075 @item @code{admin-server}
28076 This field is a string identifying the host where the administration server is
28080 This field is a string identifying the key distribution center
28085 @deftp {Data Type} krb5-configuration
28088 @item @code{allow-weak-crypto?} (default: @code{#f})
28089 If this flag is @code{#t} then services which only offer encryption algorithms
28090 known to be weak will be accepted.
28092 @item @code{default-realm} (default: @code{#f})
28093 This field should be a string identifying the default Kerberos
28094 realm for the client.
28095 You should set this field to the name of your Kerberos realm.
28096 If this value is @code{#f}
28097 then a realm must be specified with every Kerberos principal when invoking programs
28098 such as @command{kinit}.
28100 @item @code{realms}
28101 This should be a non-empty list of @code{krb5-realm} objects, which clients may
28103 Normally, one of them will have a @code{name} field matching the @code{default-realm}
28109 @subsubheading PAM krb5 Service
28112 The @code{pam-krb5} service allows for login authentication and password
28113 management via Kerberos.
28114 You will need this service if you want PAM enabled applications to authenticate
28115 users using Kerberos.
28117 @defvr {Scheme Variable} pam-krb5-service-type
28118 A service type for the Kerberos 5 PAM module.
28121 @deftp {Data Type} pam-krb5-configuration
28122 Data type representing the configuration of the Kerberos 5 PAM module.
28123 This type has the following parameters:
28125 @item @code{pam-krb5} (default: @code{pam-krb5})
28126 The pam-krb5 package to use.
28128 @item @code{minimum-uid} (default: @code{1000})
28129 The smallest user ID for which Kerberos authentications should be attempted.
28130 Local accounts with lower values will silently fail to authenticate.
28135 @node LDAP Services
28136 @subsection LDAP Services
28138 @cindex nslcd, LDAP service
28140 The @code{(gnu services authentication)} module provides the
28141 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
28142 server. In addition to configuring the service itself, you may want to add
28143 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
28144 Switch} for detailed information.
28146 Here is a simple operating system declaration with a default configuration of
28147 the @code{nslcd-service-type} and a Name Service Switch configuration that
28148 consults the @code{ldap} name service last:
28151 (use-service-modules authentication)
28152 (use-modules (gnu system nss))
28158 (service nslcd-service-type)
28159 (service dhcp-client-service-type)
28161 (name-service-switch
28162 (let ((services (list (name-service (name "db"))
28163 (name-service (name "files"))
28164 (name-service (name "ldap")))))
28165 (name-service-switch
28166 (inherit %mdns-host-lookup-nss)
28167 (password services)
28170 (netgroup services)
28171 (gshadow services)))))
28174 @c %start of generated documentation for nslcd-configuration
28176 Available @code{nslcd-configuration} fields are:
28178 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
28179 The @code{nss-pam-ldapd} package to use.
28183 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
28184 The number of threads to start that can handle requests and perform LDAP
28185 queries. Each thread opens a separate connection to the LDAP server.
28186 The default is to start 5 threads.
28188 Defaults to @samp{disabled}.
28192 @deftypevr {@code{nslcd-configuration} parameter} string uid
28193 This specifies the user id with which the daemon should be run.
28195 Defaults to @samp{"nslcd"}.
28199 @deftypevr {@code{nslcd-configuration} parameter} string gid
28200 This specifies the group id with which the daemon should be run.
28202 Defaults to @samp{"nslcd"}.
28206 @deftypevr {@code{nslcd-configuration} parameter} log-option log
28207 This option controls the way logging is done via a list containing
28208 SCHEME and LEVEL@. The SCHEME argument may either be the symbols
28209 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
28210 argument is optional and specifies the log level. The log level may be
28211 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
28212 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
28213 specified log level or higher are logged.
28215 Defaults to @samp{("/var/log/nslcd" info)}.
28219 @deftypevr {@code{nslcd-configuration} parameter} list uri
28220 The list of LDAP server URIs. Normally, only the first server will be
28221 used with the following servers as fall-back.
28223 Defaults to @samp{("ldap://localhost:389/")}.
28227 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
28228 The version of the LDAP protocol to use. The default is to use the
28229 maximum version supported by the LDAP library.
28231 Defaults to @samp{disabled}.
28235 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
28236 Specifies the distinguished name with which to bind to the directory
28237 server for lookups. The default is to bind anonymously.
28239 Defaults to @samp{disabled}.
28243 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
28244 Specifies the credentials with which to bind. This option is only
28245 applicable when used with binddn.
28247 Defaults to @samp{disabled}.
28251 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
28252 Specifies the distinguished name to use when the root user tries to
28253 modify a user's password using the PAM module.
28255 Defaults to @samp{disabled}.
28259 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
28260 Specifies the credentials with which to bind if the root user tries to
28261 change a user's password. This option is only applicable when used with
28264 Defaults to @samp{disabled}.
28268 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
28269 Specifies the SASL mechanism to be used when performing SASL
28272 Defaults to @samp{disabled}.
28276 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
28277 Specifies the SASL realm to be used when performing SASL authentication.
28279 Defaults to @samp{disabled}.
28283 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
28284 Specifies the authentication identity to be used when performing SASL
28287 Defaults to @samp{disabled}.
28291 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
28292 Specifies the authorization identity to be used when performing SASL
28295 Defaults to @samp{disabled}.
28299 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
28300 Determines whether the LDAP server host name should be canonicalised. If
28301 this is enabled the LDAP library will do a reverse host name lookup. By
28302 default, it is left up to the LDAP library whether this check is
28305 Defaults to @samp{disabled}.
28309 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
28310 Set the name for the GSS-API Kerberos credentials cache.
28312 Defaults to @samp{disabled}.
28316 @deftypevr {@code{nslcd-configuration} parameter} string base
28317 The directory search base.
28319 Defaults to @samp{"dc=example,dc=com"}.
28323 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
28324 Specifies the search scope (subtree, onelevel, base or children). The
28325 default scope is subtree; base scope is almost never useful for name
28326 service lookups; children scope is not supported on all servers.
28328 Defaults to @samp{(subtree)}.
28332 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
28333 Specifies the policy for dereferencing aliases. The default policy is
28334 to never dereference aliases.
28336 Defaults to @samp{disabled}.
28340 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
28341 Specifies whether automatic referral chasing should be enabled. The
28342 default behaviour is to chase referrals.
28344 Defaults to @samp{disabled}.
28348 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
28349 This option allows for custom attributes to be looked up instead of the
28350 default RFC 2307 attributes. It is a list of maps, each consisting of
28351 the name of a map, the RFC 2307 attribute to match and the query
28352 expression for the attribute as it is available in the directory.
28354 Defaults to @samp{()}.
28358 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
28359 A list of filters consisting of the name of a map to which the filter
28360 applies and an LDAP search filter expression.
28362 Defaults to @samp{()}.
28366 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
28367 Specifies the time limit in seconds to use when connecting to the
28368 directory server. The default value is 10 seconds.
28370 Defaults to @samp{disabled}.
28374 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
28375 Specifies the time limit (in seconds) to wait for a response from the
28376 LDAP server. A value of zero, which is the default, is to wait
28377 indefinitely for searches to be completed.
28379 Defaults to @samp{disabled}.
28383 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
28384 Specifies the period if inactivity (in seconds) after which the con‐
28385 nection to the LDAP server will be closed. The default is not to time
28388 Defaults to @samp{disabled}.
28392 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
28393 Specifies the number of seconds to sleep when connecting to all LDAP
28394 servers fails. By default one second is waited between the first
28395 failure and the first retry.
28397 Defaults to @samp{disabled}.
28401 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
28402 Specifies the time after which the LDAP server is considered to be
28403 permanently unavailable. Once this time is reached retries will be done
28404 only once per this time period. The default value is 10 seconds.
28406 Defaults to @samp{disabled}.
28410 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
28411 Specifies whether to use SSL/TLS or not (the default is not to). If
28412 'start-tls is specified then StartTLS is used rather than raw LDAP over
28415 Defaults to @samp{disabled}.
28419 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
28420 Specifies what checks to perform on a server-supplied certificate. The
28421 meaning of the values is described in the ldap.conf(5) manual page.
28423 Defaults to @samp{disabled}.
28427 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
28428 Specifies the directory containing X.509 certificates for peer authen‐
28429 tication. This parameter is ignored when using GnuTLS.
28431 Defaults to @samp{disabled}.
28435 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
28436 Specifies the path to the X.509 certificate for peer authentication.
28438 Defaults to @samp{disabled}.
28442 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
28443 Specifies the path to an entropy source. This parameter is ignored when
28446 Defaults to @samp{disabled}.
28450 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
28451 Specifies the ciphers to use for TLS as a string.
28453 Defaults to @samp{disabled}.
28457 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
28458 Specifies the path to the file containing the local certificate for
28459 client TLS authentication.
28461 Defaults to @samp{disabled}.
28465 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
28466 Specifies the path to the file containing the private key for client TLS
28469 Defaults to @samp{disabled}.
28473 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
28474 Set this to a number greater than 0 to request paged results from the
28475 LDAP server in accordance with RFC2696. The default (0) is to not
28476 request paged results.
28478 Defaults to @samp{disabled}.
28482 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
28483 This option prevents group membership lookups through LDAP for the
28484 specified users. Alternatively, the value 'all-local may be used. With
28485 that value nslcd builds a full list of non-LDAP users on startup.
28487 Defaults to @samp{disabled}.
28491 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
28492 This option ensures that LDAP users with a numeric user id lower than
28493 the specified value are ignored.
28495 Defaults to @samp{disabled}.
28499 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
28500 This option specifies an offset that is added to all LDAP numeric user
28501 ids. This can be used to avoid user id collisions with local users.
28503 Defaults to @samp{disabled}.
28507 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
28508 This option specifies an offset that is added to all LDAP numeric group
28509 ids. This can be used to avoid user id collisions with local groups.
28511 Defaults to @samp{disabled}.
28515 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
28516 If this option is set, the member attribute of a group may point to
28517 another group. Members of nested groups are also returned in the higher
28518 level group and parent groups are returned when finding groups for a
28519 specific user. The default is not to perform extra searches for nested
28522 Defaults to @samp{disabled}.
28526 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
28527 If this option is set, the group member list is not retrieved when
28528 looking up groups. Lookups for finding which groups a user belongs to
28529 will remain functional so the user will likely still get the correct
28530 groups assigned on login.
28532 Defaults to @samp{disabled}.
28536 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
28537 If this option is set, functions which cause all user/group entries to
28538 be loaded from the directory will not succeed in doing so. This can
28539 dramatically reduce LDAP server load in situations where there are a
28540 great number of users and/or groups. This option is not recommended for
28541 most configurations.
28543 Defaults to @samp{disabled}.
28547 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
28548 This option can be used to specify how user and group names are verified
28549 within the system. This pattern is used to check all user and group
28550 names that are requested and returned from LDAP.
28552 Defaults to @samp{disabled}.
28556 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
28557 This specifies whether or not to perform searches using case-insensitive
28558 matching. Enabling this could open up the system to authorization
28559 bypass vulnerabilities and introduce nscd cache poisoning
28560 vulnerabilities which allow denial of service.
28562 Defaults to @samp{disabled}.
28566 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
28567 This option specifies whether password policy controls are requested and
28568 handled from the LDAP server when performing user authentication.
28570 Defaults to @samp{disabled}.
28574 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
28575 By default nslcd performs an LDAP search with the user's credentials
28576 after BIND (authentication) to ensure that the BIND operation was
28577 successful. The default search is a simple check to see if the user's
28578 DN exists. A search filter can be specified that will be used instead.
28579 It should return at least one entry.
28581 Defaults to @samp{disabled}.
28585 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
28586 This option allows flexible fine tuning of the authorisation check that
28587 should be performed. The search filter specified is executed and if any
28588 entries match, access is granted, otherwise access is denied.
28590 Defaults to @samp{disabled}.
28594 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
28595 If this option is set password modification using pam_ldap will be
28596 denied and the specified message will be presented to the user instead.
28597 The message can be used to direct the user to an alternative means of
28598 changing their password.
28600 Defaults to @samp{disabled}.
28604 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
28605 List of pam service names for which LDAP authentication should suffice.
28607 Defaults to @samp{()}.
28611 @c %end of generated documentation for nslcd-configuration
28615 @subsection Web Services
28620 The @code{(gnu services web)} module provides the Apache HTTP Server,
28621 the nginx web server, and also a fastcgi wrapper daemon.
28623 @subsubheading Apache HTTP Server
28625 @deffn {Scheme Variable} httpd-service-type
28626 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
28627 (@dfn{httpd}). The value for this service type is a
28628 @code{httpd-configuration} record.
28630 A simple example configuration is given below.
28633 (service httpd-service-type
28634 (httpd-configuration
28637 (server-name "www.example.com")
28638 (document-root "/srv/http/www.example.com")))))
28641 Other services can also extend the @code{httpd-service-type} to add to
28645 (simple-service 'www.example.com-server httpd-service-type
28649 (list (string-join '("ServerName www.example.com"
28650 "DocumentRoot /srv/http/www.example.com")
28655 The details for the @code{httpd-configuration}, @code{httpd-module},
28656 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
28659 @deffn {Data Type} httpd-configuration
28660 This data type represents the configuration for the httpd service.
28663 @item @code{package} (default: @code{httpd})
28664 The httpd package to use.
28666 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28667 The pid file used by the shepherd-service.
28669 @item @code{config} (default: @code{(httpd-config-file)})
28670 The configuration file to use with the httpd service. The default value
28671 is a @code{httpd-config-file} record, but this can also be a different
28672 G-expression that generates a file, for example a @code{plain-file}. A
28673 file outside of the store can also be specified through a string.
28678 @deffn {Data Type} httpd-module
28679 This data type represents a module for the httpd service.
28683 The name of the module.
28686 The file for the module. This can be relative to the httpd package being
28687 used, the absolute location of a file, or a G-expression for a file
28688 within the store, for example @code{(file-append mod-wsgi
28689 "/modules/mod_wsgi.so")}.
28694 @defvr {Scheme Variable} %default-httpd-modules
28695 A default list of @code{httpd-module} objects.
28698 @deffn {Data Type} httpd-config-file
28699 This data type represents a configuration file for the httpd service.
28702 @item @code{modules} (default: @code{%default-httpd-modules})
28703 The modules to load. Additional modules can be added here, or loaded by
28704 additional configuration.
28706 For example, in order to handle requests for PHP files, you can use Apache’s
28707 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
28710 (service httpd-service-type
28711 (httpd-configuration
28716 (name "proxy_module")
28717 (file "modules/mod_proxy.so"))
28719 (name "proxy_fcgi_module")
28720 (file "modules/mod_proxy_fcgi.so"))
28721 %default-httpd-modules))
28722 (extra-config (list "\
28723 <FilesMatch \\.php$>
28724 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
28725 </FilesMatch>"))))))
28726 (service php-fpm-service-type
28727 (php-fpm-configuration
28728 (socket "/var/run/php-fpm.sock")
28729 (socket-group "httpd")))
28732 @item @code{server-root} (default: @code{httpd})
28733 The @code{ServerRoot} in the configuration file, defaults to the httpd
28734 package. Directives including @code{Include} and @code{LoadModule} are
28735 taken as relative to the server root.
28737 @item @code{server-name} (default: @code{#f})
28738 The @code{ServerName} in the configuration file, used to specify the
28739 request scheme, hostname and port that the server uses to identify
28742 This doesn't need to be set in the server config, and can be specified
28743 in virtual hosts. The default is @code{#f} to not specify a
28746 @item @code{document-root} (default: @code{"/srv/http"})
28747 The @code{DocumentRoot} from which files will be served.
28749 @item @code{listen} (default: @code{'("80")})
28750 The list of values for the @code{Listen} directives in the config
28751 file. The value should be a list of strings, when each string can
28752 specify the port number to listen on, and optionally the IP address and
28755 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28756 The @code{PidFile} to use. This should match the @code{pid-file} set in
28757 the @code{httpd-configuration} so that the Shepherd service is
28758 configured correctly.
28760 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
28761 The @code{ErrorLog} to which the server will log errors.
28763 @item @code{user} (default: @code{"httpd"})
28764 The @code{User} which the server will answer requests as.
28766 @item @code{group} (default: @code{"httpd"})
28767 The @code{Group} which the server will answer requests as.
28769 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
28770 A flat list of strings and G-expressions which will be added to the end
28771 of the configuration file.
28773 Any values which the service is extended with will be appended to this
28779 @deffn {Data Type} httpd-virtualhost
28780 This data type represents a virtualhost configuration block for the httpd service.
28782 These should be added to the extra-config for the httpd-service.
28785 (simple-service 'www.example.com-server httpd-service-type
28789 (list (string-join '("ServerName www.example.com"
28790 "DocumentRoot /srv/http/www.example.com")
28795 @item @code{addresses-and-ports}
28796 The addresses and ports for the @code{VirtualHost} directive.
28798 @item @code{contents}
28799 The contents of the @code{VirtualHost} directive, this should be a list
28800 of strings and G-expressions.
28806 @subsubheading NGINX
28808 @deffn {Scheme Variable} nginx-service-type
28809 Service type for the @uref{https://nginx.org/,NGinx} web server. The
28810 value for this service type is a @code{<nginx-configuration>} record.
28812 A simple example configuration is given below.
28815 (service nginx-service-type
28816 (nginx-configuration
28818 (list (nginx-server-configuration
28819 (server-name '("www.example.com"))
28820 (root "/srv/http/www.example.com"))))))
28823 In addition to adding server blocks to the service configuration
28824 directly, this service can be extended by other services to add server
28825 blocks, as in this example:
28828 (simple-service 'my-extra-server nginx-service-type
28829 (list (nginx-server-configuration
28830 (root "/srv/http/extra-website")
28831 (try-files (list "$uri" "$uri/index.html")))))
28835 At startup, @command{nginx} has not yet read its configuration file, so
28836 it uses a default file to log error messages. If it fails to load its
28837 configuration file, that is where error messages are logged. After the
28838 configuration file is loaded, the default error log file changes as per
28839 configuration. In our case, startup error messages can be found in
28840 @file{/var/run/nginx/logs/error.log}, and after configuration in
28841 @file{/var/log/nginx/error.log}. The second location can be changed
28842 with the @var{log-directory} configuration option.
28844 @deffn {Data Type} nginx-configuration
28845 This data type represents the configuration for NGinx. Some
28846 configuration can be done through this and the other provided record
28847 types, or alternatively, a config file can be provided.
28850 @item @code{nginx} (default: @code{nginx})
28851 The nginx package to use.
28853 @item @code{shepherd-requirement} (default: @code{'()})
28854 This is a list of symbols naming Shepherd services the nginx service
28857 This is useful if you would like @command{nginx} to be started after a
28858 back-end web server or a logging service such as Anonip has been
28861 @item @code{log-directory} (default: @code{"/var/log/nginx"})
28862 The directory to which NGinx will write log files.
28864 @item @code{run-directory} (default: @code{"/var/run/nginx"})
28865 The directory in which NGinx will create a pid file, and write temporary
28868 @item @code{server-blocks} (default: @code{'()})
28869 A list of @dfn{server blocks} to create in the generated configuration
28870 file, the elements should be of type
28871 @code{<nginx-server-configuration>}.
28873 The following example would setup NGinx to serve @code{www.example.com}
28874 from the @code{/srv/http/www.example.com} directory, without using
28877 (service nginx-service-type
28878 (nginx-configuration
28880 (list (nginx-server-configuration
28881 (server-name '("www.example.com"))
28882 (root "/srv/http/www.example.com"))))))
28885 @item @code{upstream-blocks} (default: @code{'()})
28886 A list of @dfn{upstream blocks} to create in the generated configuration
28887 file, the elements should be of type
28888 @code{<nginx-upstream-configuration>}.
28890 Configuring upstreams through the @code{upstream-blocks} can be useful
28891 when combined with @code{locations} in the
28892 @code{<nginx-server-configuration>} records. The following example
28893 creates a server configuration with one location configuration, that
28894 will proxy requests to a upstream configuration, which will handle
28895 requests with two servers.
28900 (nginx-configuration
28902 (list (nginx-server-configuration
28903 (server-name '("www.example.com"))
28904 (root "/srv/http/www.example.com")
28907 (nginx-location-configuration
28909 (body '("proxy_pass http://server-proxy;"))))))))
28911 (list (nginx-upstream-configuration
28912 (name "server-proxy")
28913 (servers (list "server1.example.com"
28914 "server2.example.com")))))))
28917 @item @code{file} (default: @code{#f})
28918 If a configuration @var{file} is provided, this will be used, rather than
28919 generating a configuration file from the provided @code{log-directory},
28920 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
28921 proper operation, these arguments should match what is in @var{file} to ensure
28922 that the directories are created when the service is activated.
28924 This can be useful if you have an existing configuration file, or it's
28925 not possible to do what is required through the other parts of the
28926 nginx-configuration record.
28928 @item @code{server-names-hash-bucket-size} (default: @code{#f})
28929 Bucket size for the server names hash tables, defaults to @code{#f} to
28930 use the size of the processors cache line.
28932 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
28933 Maximum bucket size for the server names hash tables.
28935 @item @code{modules} (default: @code{'()})
28936 List of nginx dynamic modules to load. This should be a list of file
28937 names of loadable modules, as in this example:
28942 (file-append nginx-accept-language-module "\
28943 /etc/nginx/modules/ngx_http_accept_language_module.so")
28944 (file-append nginx-lua-module "\
28945 /etc/nginx/modules/ngx_http_lua_module.so")))
28948 @item @code{lua-package-path} (default: @code{'()})
28949 List of nginx lua packages to load. This should be a list of package
28950 names of loadable lua modules, as in this example:
28953 (lua-package-path (list lua-resty-core
28960 @item @code{lua-package-cpath} (default: @code{'()})
28961 List of nginx lua C packages to load. This should be a list of package
28962 names of loadable lua C modules, as in this example:
28965 (lua-package-cpath (list lua-resty-signal))
28968 @item @code{global-directives} (default: @code{'((events . ()))})
28969 Association list of global directives for the top level of the nginx
28970 configuration. Values may themselves be association lists.
28974 `((worker_processes . 16)
28976 (events . ((worker_connections . 1024)))))
28979 @item @code{extra-content} (default: @code{""})
28980 Extra content for the @code{http} block. Should be string or a string
28981 valued G-expression.
28986 @anchor{nginx-server-configuration}
28987 @deftp {Data Type} nginx-server-configuration
28988 Data type representing the configuration of an nginx server block.
28989 This type has the following parameters:
28992 @item @code{listen} (default: @code{'("80" "443 ssl")})
28993 Each @code{listen} directive sets the address and port for IP, or the
28994 path for a UNIX-domain socket on which the server will accept requests.
28995 Both address and port, or only address or only port can be specified.
28996 An address may also be a hostname, for example:
28999 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
29002 @item @code{server-name} (default: @code{(list 'default)})
29003 A list of server names this server represents. @code{'default} represents the
29004 default server for connections matching no other server.
29006 @item @code{root} (default: @code{"/srv/http"})
29007 Root of the website nginx will serve.
29009 @item @code{locations} (default: @code{'()})
29010 A list of @dfn{nginx-location-configuration} or
29011 @dfn{nginx-named-location-configuration} records to use within this
29014 @item @code{index} (default: @code{(list "index.html")})
29015 Index files to look for when clients ask for a directory. If it cannot be found,
29016 Nginx will send the list of files in the directory.
29018 @item @code{try-files} (default: @code{'()})
29019 A list of files whose existence is checked in the specified order.
29020 @code{nginx} will use the first file it finds to process the request.
29022 @item @code{ssl-certificate} (default: @code{#f})
29023 Where to find the certificate for secure connections. Set it to @code{#f} if
29024 you don't have a certificate or you don't want to use HTTPS.
29026 @item @code{ssl-certificate-key} (default: @code{#f})
29027 Where to find the private key for secure connections. Set it to @code{#f} if
29028 you don't have a key or you don't want to use HTTPS.
29030 @item @code{server-tokens?} (default: @code{#f})
29031 Whether the server should add its configuration to response.
29033 @item @code{raw-content} (default: @code{'()})
29034 A list of raw lines added to the server block.
29039 @deftp {Data Type} nginx-upstream-configuration
29040 Data type representing the configuration of an nginx @code{upstream}
29041 block. This type has the following parameters:
29045 Name for this group of servers.
29047 @item @code{servers}
29048 Specify the addresses of the servers in the group. The address can be
29049 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
29050 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
29051 prefix @samp{unix:}. For addresses using an IP address or domain name,
29052 the default port is 80, and a different port can be specified
29055 @item @code{extra-content}
29056 A string or list of strings to add to the upstream block.
29061 @deftp {Data Type} nginx-location-configuration
29062 Data type representing the configuration of an nginx @code{location}
29063 block. This type has the following parameters:
29067 URI which this location block matches.
29069 @anchor{nginx-location-configuration body}
29071 Body of the location block, specified as a list of strings. This can contain
29073 configuration directives. For example, to pass requests to a upstream
29074 server group defined using an @code{nginx-upstream-configuration} block,
29075 the following directive would be specified in the body @samp{(list "proxy_pass
29076 http://upstream-name;")}.
29081 @deftp {Data Type} nginx-named-location-configuration
29082 Data type representing the configuration of an nginx named location
29083 block. Named location blocks are used for request redirection, and not
29084 used for regular request processing. This type has the following
29089 Name to identify this location block.
29092 @xref{nginx-location-configuration body}, as the body for named location
29093 blocks can be used in a similar way to the
29094 @code{nginx-location-configuration body}. One restriction is that the
29095 body of a named location block cannot contain location blocks.
29100 @subsubheading Varnish Cache
29102 Varnish is a fast cache server that sits in between web applications
29103 and end users. It proxies requests from clients and caches the
29104 accessed URLs such that multiple requests for the same resource only
29105 creates one request to the back-end.
29107 @defvr {Scheme Variable} varnish-service-type
29108 Service type for the Varnish daemon.
29111 @deftp {Data Type} varnish-configuration
29112 Data type representing the @code{varnish} service configuration.
29113 This type has the following parameters:
29116 @item @code{package} (default: @code{varnish})
29117 The Varnish package to use.
29119 @item @code{name} (default: @code{"default"})
29120 A name for this Varnish instance. Varnish will create a directory in
29121 @file{/var/varnish/} with this name and keep temporary files there. If
29122 the name starts with a forward slash, it is interpreted as an absolute
29125 Pass the @code{-n} argument to other Varnish programs to connect to the
29126 named instance, e.g.@: @command{varnishncsa -n default}.
29128 @item @code{backend} (default: @code{"localhost:8080"})
29129 The backend to use. This option has no effect if @code{vcl} is set.
29131 @item @code{vcl} (default: #f)
29132 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
29133 is @code{#f}, Varnish will proxy @code{backend} using the default
29134 configuration. Otherwise this must be a file-like object with valid
29137 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
29138 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
29139 can do something along these lines:
29142 (define %gnu-mirror
29143 (plain-file "gnu.vcl"
29145 backend gnu @{ .host = \"www.gnu.org\"; @}"))
29149 (services (cons (service varnish-service-type
29150 (varnish-configuration
29152 (vcl %gnu-mirror)))
29156 The configuration of an already running Varnish instance can be inspected
29157 and changed using the @command{varnishadm} program.
29159 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
29160 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
29161 comprehensive documentation on Varnish and its configuration language.
29163 @item @code{listen} (default: @code{'("localhost:80")})
29164 List of addresses Varnish will listen on.
29166 @item @code{storage} (default: @code{'("malloc,128m")})
29167 List of storage backends that will be available in VCL.
29169 @item @code{parameters} (default: @code{'()})
29170 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
29172 @item @code{extra-options} (default: @code{'()})
29173 Additional arguments to pass to the @command{varnishd} process.
29178 @subsubheading Patchwork
29180 Patchwork is a patch tracking system. It can collect patches sent to a
29181 mailing list, and display them in a web interface.
29183 @defvr {Scheme Variable} patchwork-service-type
29184 Service type for Patchwork.
29187 The following example is an example of a minimal service for Patchwork, for
29188 the @code{patchwork.example.com} domain.
29191 (service patchwork-service-type
29192 (patchwork-configuration
29193 (domain "patchwork.example.com")
29195 (patchwork-settings-module
29196 (allowed-hosts (list domain))
29197 (default-from-email "patchwork@@patchwork.example.com")))
29198 (getmail-retriever-config
29199 (getmail-retriever-configuration
29200 (type "SimpleIMAPSSLRetriever")
29201 (server "imap.example.com")
29203 (username "patchwork")
29205 (list (file-append coreutils "/bin/cat")
29206 "/etc/getmail-patchwork-imap-password"))
29208 '((mailboxes . ("Patches"))))))))
29212 There are three records for configuring the Patchwork service. The
29213 @code{<patchwork-configuration>} relates to the configuration for Patchwork
29214 within the HTTPD service.
29216 The @code{settings-module} field within the @code{<patchwork-configuration>}
29217 record can be populated with the @code{<patchwork-settings-module>} record,
29218 which describes a settings module that is generated within the Guix store.
29220 For the @code{database-configuration} field within the
29221 @code{<patchwork-settings-module>}, the
29222 @code{<patchwork-database-configuration>} must be used.
29224 @deftp {Data Type} patchwork-configuration
29225 Data type representing the Patchwork service configuration. This type has the
29226 following parameters:
29229 @item @code{patchwork} (default: @code{patchwork})
29230 The Patchwork package to use.
29232 @item @code{domain}
29233 The domain to use for Patchwork, this is used in the HTTPD service virtual
29236 @item @code{settings-module}
29237 The settings module to use for Patchwork. As a Django application, Patchwork
29238 is configured with a Python module containing the settings. This can either be
29239 an instance of the @code{<patchwork-settings-module>} record, any other record
29240 that represents the settings in the store, or a directory outside of the
29243 @item @code{static-path} (default: @code{"/static/"})
29244 The path under which the HTTPD service should serve the static files.
29246 @item @code{getmail-retriever-config}
29247 The getmail-retriever-configuration record value to use with
29248 Patchwork. Getmail will be configured with this value, the messages will be
29249 delivered to Patchwork.
29254 @deftp {Data Type} patchwork-settings-module
29255 Data type representing a settings module for Patchwork. Some of these
29256 settings relate directly to Patchwork, but others relate to Django, the web
29257 framework used by Patchwork, or the Django Rest Framework library. This type
29258 has the following parameters:
29261 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
29262 The database connection settings used for Patchwork. See the
29263 @code{<patchwork-database-configuration>} record type for more information.
29265 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
29266 Patchwork, as a Django web application uses a secret key for cryptographically
29267 signing values. This file should contain a unique unpredictable value.
29269 If this file does not exist, it will be created and populated with a random
29270 value by the patchwork-setup shepherd service.
29272 This setting relates to Django.
29274 @item @code{allowed-hosts}
29275 A list of valid hosts for this Patchwork service. This should at least include
29276 the domain specified in the @code{<patchwork-configuration>} record.
29278 This is a Django setting.
29280 @item @code{default-from-email}
29281 The email address from which Patchwork should send email by default.
29283 This is a Patchwork setting.
29285 @item @code{static-url} (default: @code{#f})
29286 The URL to use when serving static assets. It can be part of a URL, or a full
29287 URL, but must end in a @code{/}.
29289 If the default value is used, the @code{static-path} value from the
29290 @code{<patchwork-configuration>} record will be used.
29292 This is a Django setting.
29294 @item @code{admins} (default: @code{'()})
29295 Email addresses to send the details of errors that occur. Each value should
29296 be a list containing two elements, the name and then the email address.
29298 This is a Django setting.
29300 @item @code{debug?} (default: @code{#f})
29301 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
29302 messages will be shown.
29304 This is a Django setting.
29306 @item @code{enable-rest-api?} (default: @code{#t})
29307 Whether to enable the Patchwork REST API.
29309 This is a Patchwork setting.
29311 @item @code{enable-xmlrpc?} (default: @code{#t})
29312 Whether to enable the XML RPC API.
29314 This is a Patchwork setting.
29316 @item @code{force-https-links?} (default: @code{#t})
29317 Whether to use HTTPS links on Patchwork pages.
29319 This is a Patchwork setting.
29321 @item @code{extra-settings} (default: @code{""})
29322 Extra code to place at the end of the Patchwork settings module.
29327 @deftp {Data Type} patchwork-database-configuration
29328 Data type representing the database configuration for Patchwork.
29331 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
29332 The database engine to use.
29334 @item @code{name} (default: @code{"patchwork"})
29335 The name of the database to use.
29337 @item @code{user} (default: @code{"httpd"})
29338 The user to connect to the database as.
29340 @item @code{password} (default: @code{""})
29341 The password to use when connecting to the database.
29343 @item @code{host} (default: @code{""})
29344 The host to make the database connection to.
29346 @item @code{port} (default: @code{""})
29347 The port on which to connect to the database.
29352 @subsubheading Mumi
29354 @cindex Mumi, Debbugs Web interface
29355 @cindex Debbugs, Mumi Web interface
29356 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
29357 Web interface to the Debbugs bug tracker, by default for
29358 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
29359 but it also fetches and indexes mail retrieved from Debbugs.
29361 @defvr {Scheme Variable} mumi-service-type
29362 This is the service type for Mumi.
29365 @deftp {Data Type} mumi-configuration
29366 Data type representing the Mumi service configuration. This type has the
29370 @item @code{mumi} (default: @code{mumi})
29371 The Mumi package to use.
29373 @item @code{mailer?} (default: @code{#true})
29374 Whether to enable or disable the mailer component.
29376 @item @code{mumi-configuration-sender}
29377 The email address used as the sender for comments.
29379 @item @code{mumi-configuration-smtp}
29380 A URI to configure the SMTP settings for Mailutils. This could be
29381 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
29382 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
29383 mailutils, GNU@tie{}Mailutils}.
29389 @subsubheading FastCGI
29392 FastCGI is an interface between the front-end and the back-end of a web
29393 service. It is a somewhat legacy facility; new web services should
29394 generally just talk HTTP between the front-end and the back-end.
29395 However there are a number of back-end services such as PHP or the
29396 optimized HTTP Git repository access that use FastCGI, so we have
29397 support for it in Guix.
29399 To use FastCGI, you configure the front-end web server (e.g., nginx) to
29400 dispatch some subset of its requests to the fastcgi backend, which
29401 listens on a local TCP or UNIX socket. There is an intermediary
29402 @code{fcgiwrap} program that sits between the actual backend process and
29403 the web server. The front-end indicates which backend program to run,
29404 passing that information to the @code{fcgiwrap} process.
29406 @defvr {Scheme Variable} fcgiwrap-service-type
29407 A service type for the @code{fcgiwrap} FastCGI proxy.
29410 @deftp {Data Type} fcgiwrap-configuration
29411 Data type representing the configuration of the @code{fcgiwrap} service.
29412 This type has the following parameters:
29414 @item @code{package} (default: @code{fcgiwrap})
29415 The fcgiwrap package to use.
29417 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
29418 The socket on which the @code{fcgiwrap} process should listen, as a
29419 string. Valid @var{socket} values include
29420 @code{unix:@var{/path/to/unix/socket}},
29421 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
29422 @code{tcp6:[@var{ipv6_addr}]:port}.
29424 @item @code{user} (default: @code{fcgiwrap})
29425 @itemx @code{group} (default: @code{fcgiwrap})
29426 The user and group names, as strings, under which to run the
29427 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
29428 the user asks for the specific user or group names @code{fcgiwrap} that
29429 the corresponding user and/or group is present on the system.
29431 It is possible to configure a FastCGI-backed web service to pass HTTP
29432 authentication information from the front-end to the back-end, and to
29433 allow @code{fcgiwrap} to run the back-end process as a corresponding
29434 local user. To enable this capability on the back-end, run
29435 @code{fcgiwrap} as the @code{root} user and group. Note that this
29436 capability also has to be configured on the front-end as well.
29441 @subsubheading PHP-FPM
29443 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
29444 with some additional features useful for sites of any size.
29446 These features include:
29448 @item Adaptive process spawning
29449 @item Basic statistics (similar to Apache's mod_status)
29450 @item Advanced process management with graceful stop/start
29451 @item Ability to start workers with different uid/gid/chroot/environment
29452 and different php.ini (replaces safe_mode)
29453 @item Stdout & stderr logging
29454 @item Emergency restart in case of accidental opcode cache destruction
29455 @item Accelerated upload support
29456 @item Support for a "slowlog"
29457 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
29458 a special function to finish request & flush all data while continuing to do
29459 something time-consuming (video converting, stats processing, etc.)
29461 ...@: and much more.
29463 @defvr {Scheme Variable} php-fpm-service-type
29464 A Service type for @code{php-fpm}.
29467 @deftp {Data Type} php-fpm-configuration
29468 Data Type for php-fpm service configuration.
29470 @item @code{php} (default: @code{php})
29471 The php package to use.
29472 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
29473 The address on which to accept FastCGI requests. Valid syntaxes are:
29475 @item @code{"ip.add.re.ss:port"}
29476 Listen on a TCP socket to a specific address on a specific port.
29477 @item @code{"port"}
29478 Listen on a TCP socket to all addresses on a specific port.
29479 @item @code{"/path/to/unix/socket"}
29480 Listen on a unix socket.
29483 @item @code{user} (default: @code{php-fpm})
29484 User who will own the php worker processes.
29485 @item @code{group} (default: @code{php-fpm})
29486 Group of the worker processes.
29487 @item @code{socket-user} (default: @code{php-fpm})
29488 User who can speak to the php-fpm socket.
29489 @item @code{socket-group} (default: @code{nginx})
29490 Group that can speak to the php-fpm socket.
29491 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
29492 The process id of the php-fpm process is written to this file
29493 once the service has started.
29494 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
29495 Log for the php-fpm master process.
29496 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
29497 Detailed settings for the php-fpm process manager.
29500 @item @code{<php-fpm-dynamic-process-manager-configuration>}
29501 @item @code{<php-fpm-static-process-manager-configuration>}
29502 @item @code{<php-fpm-on-demand-process-manager-configuration>}
29504 @item @code{display-errors} (default @code{#f})
29505 Determines whether php errors and warning should be sent to clients
29506 and displayed in their browsers.
29507 This is useful for local php development, but a security risk for public sites,
29508 as error messages can reveal passwords and personal data.
29509 @item @code{timezone} (default @code{#f})
29510 Specifies @code{php_admin_value[date.timezone]} parameter.
29511 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
29512 This file will log the @code{stderr} outputs of php worker processes.
29513 Can be set to @code{#f} to disable logging.
29514 @item @code{file} (default @code{#f})
29515 An optional override of the whole configuration.
29516 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29517 @item @code{php-ini-file} (default @code{#f})
29518 An optional override of the default php settings.
29519 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
29520 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29522 For local development it is useful to set a higher timeout and memory
29523 limit for spawned php processes. This be accomplished with the
29524 following operating system configuration snippet:
29526 (define %local-php-ini
29527 (plain-file "php.ini"
29529 max_execution_time = 1800"))
29533 (services (cons (service php-fpm-service-type
29534 (php-fpm-configuration
29535 (php-ini-file %local-php-ini)))
29539 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
29540 directives} for comprehensive documentation on the acceptable
29541 @file{php.ini} directives.
29545 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
29546 Data Type for the @code{dynamic} php-fpm process manager. With the
29547 @code{dynamic} process manager, spare worker processes are kept around
29548 based on its configured limits.
29550 @item @code{max-children} (default: @code{5})
29551 Maximum of worker processes.
29552 @item @code{start-servers} (default: @code{2})
29553 How many worker processes should be started on start-up.
29554 @item @code{min-spare-servers} (default: @code{1})
29555 How many spare worker processes should be kept around at minimum.
29556 @item @code{max-spare-servers} (default: @code{3})
29557 How many spare worker processes should be kept around at maximum.
29561 @deftp {Data type} php-fpm-static-process-manager-configuration
29562 Data Type for the @code{static} php-fpm process manager. With the
29563 @code{static} process manager, an unchanging number of worker processes
29566 @item @code{max-children} (default: @code{5})
29567 Maximum of worker processes.
29571 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
29572 Data Type for the @code{on-demand} php-fpm process manager. With the
29573 @code{on-demand} process manager, worker processes are only created as
29576 @item @code{max-children} (default: @code{5})
29577 Maximum of worker processes.
29578 @item @code{process-idle-timeout} (default: @code{10})
29579 The time in seconds after which a process with no requests is killed.
29584 @deffn {Scheme Procedure} nginx-php-location @
29585 [#:nginx-package nginx] @
29586 [socket (string-append "/var/run/php" @
29587 (version-major (package-version php)) @
29589 A helper function to quickly add php to an @code{nginx-server-configuration}.
29592 A simple services setup for nginx with php can look like this:
29594 (services (cons* (service dhcp-client-service-type)
29595 (service php-fpm-service-type)
29596 (service nginx-service-type
29597 (nginx-server-configuration
29598 (server-name '("example.com"))
29599 (root "/srv/http/")
29601 (list (nginx-php-location)))
29603 (ssl-certificate #f)
29604 (ssl-certificate-key #f)))
29608 @cindex cat-avatar-generator
29609 The cat avatar generator is a simple service to demonstrate the use of php-fpm
29610 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
29611 the hash of a user's email address.
29613 @deffn {Scheme Procedure} cat-avatar-generator-service @
29614 [#:cache-dir "/var/cache/cat-avatar-generator"] @
29615 [#:package cat-avatar-generator] @
29616 [#:configuration (nginx-server-configuration)]
29617 Returns an nginx-server-configuration that inherits @code{configuration}. It
29618 extends the nginx configuration to add a server block that serves @code{package},
29619 a version of cat-avatar-generator. During execution, cat-avatar-generator will
29620 be able to use @code{cache-dir} as its cache directory.
29623 A simple setup for cat-avatar-generator can look like this:
29625 (services (cons* (cat-avatar-generator-service
29627 (nginx-server-configuration
29628 (server-name '("example.com"))))
29633 @subsubheading Hpcguix-web
29635 @cindex hpcguix-web
29636 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
29637 program is a customizable web interface to browse Guix packages,
29638 initially designed for users of high-performance computing (HPC)
29641 @defvr {Scheme Variable} hpcguix-web-service-type
29642 The service type for @code{hpcguix-web}.
29645 @deftp {Data Type} hpcguix-web-configuration
29646 Data type for the hpcguix-web service configuration.
29650 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
29651 configuration. The main items available in this spec are:
29654 @item @code{title-prefix} (default: @code{"hpcguix | "})
29655 The page title prefix.
29657 @item @code{guix-command} (default: @code{"guix"})
29658 The @command{guix} command.
29660 @item @code{package-filter-proc} (default: @code{(const #t)})
29661 A procedure specifying how to filter packages that are displayed.
29663 @item @code{package-page-extension-proc} (default: @code{(const '())})
29664 Extension package for @code{hpcguix-web}.
29666 @item @code{menu} (default: @code{'()})
29667 Additional entry in page @code{menu}.
29669 @item @code{channels} (default: @code{%default-channels})
29670 List of channels from which the package list is built (@pxref{Channels}).
29672 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
29673 The expiration time, in seconds, after which the package list is rebuilt from
29674 the latest instances of the given channels.
29677 See the hpcguix-web repository for a
29678 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
29681 @item @code{package} (default: @code{hpcguix-web})
29682 The hpcguix-web package to use.
29684 @item @code{address} (default: @code{"127.0.0.1"})
29685 The IP address to listen to.
29687 @item @code{port} (default: @code{5000})
29688 The port number to listen to.
29692 A typical hpcguix-web service declaration looks like this:
29695 (service hpcguix-web-service-type
29696 (hpcguix-web-configuration
29698 #~(define site-config
29699 (hpcweb-configuration
29700 (title-prefix "Guix-HPC - ")
29701 (menu '(("/about" "ABOUT"))))))))
29705 The hpcguix-web service periodically updates the package list it publishes by
29706 pulling channels from Git. To that end, it needs to access X.509 certificates
29707 so that it can authenticate Git servers when communicating over HTTPS, and it
29708 assumes that @file{/etc/ssl/certs} contains those certificates.
29710 Thus, make sure to add @code{nss-certs} or another certificate package to the
29711 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
29712 more information on X.509 certificates.
29715 @subsubheading gmnisrv
29718 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
29719 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
29721 @deffn {Scheme Variable} gmnisrv-service-type
29722 This is the type of the gmnisrv service, whose value should be a
29723 @code{gmnisrv-configuration} object, as in this example:
29726 (service gmnisrv-service-type
29727 (gmnisrv-configuration
29728 (config-file (local-file "./my-gmnisrv.ini"))))
29732 @deftp {Data Type} gmnisrv-configuration
29733 Data type representing the configuration of gmnisrv.
29736 @item @code{package} (default: @var{gmnisrv})
29737 Package object of the gmnisrv server.
29739 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
29740 File-like object of the gmnisrv configuration file to use. The default
29741 configuration listens on port 1965 and serves files from
29742 @file{/srv/gemini}. Certificates are stored in
29743 @file{/var/lib/gemini/certs}. For more information, run @command{man
29744 gmnisrv} and @command{man gmnisrv.ini}.
29749 @subsubheading Agate
29752 The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
29753 (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
29754 program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
29755 protocol server written in Rust.
29757 @deffn {Scheme Variable} agate-service-type
29758 This is the type of the agate service, whose value should be an
29759 @code{agate-service-type} object, as in this example:
29762 (service agate-service-type
29763 (agate-configuration
29764 (content "/srv/gemini")
29765 (cert "/srv/cert.pem")
29766 (key "/srv/key.rsa")))
29769 The example above represents the minimal tweaking necessary to get Agate
29770 up and running. Specifying the path to the certificate and key is
29771 always necessary, as the Gemini protocol requires TLS by default.
29773 To obtain a certificate and a key, you could, for example, use OpenSSL,
29774 running a command similar to the following example:
29777 openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
29778 -days 3650 -nodes -subj "/CN=example.com"
29781 Of course, you'll have to replace @i{example.com} with your own domain
29782 name, and then point the Agate configuration towards the path of the
29783 generated key and certificate.
29787 @deftp {Data Type} agate-configuration
29788 Data type representing the configuration of Agate.
29791 @item @code{package} (default: @code{agate})
29792 The package object of the Agate server.
29794 @item @code{content} (default: @file{"/srv/gemini"})
29795 The directory from which Agate will serve files.
29797 @item @code{cert} (default: @code{#f})
29798 The path to the TLS certificate PEM file to be used for encrypted
29799 connections. Must be filled in with a value from the user.
29801 @item @code{key} (default: @code{#f})
29802 The path to the PKCS8 private key file to be used for encrypted
29803 connections. Must be filled in with a value from the user.
29805 @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
29806 A list of the addresses to listen on.
29808 @item @code{hostname} (default: @code{#f})
29809 The domain name of this Gemini server. Optional.
29811 @item @code{lang} (default: @code{#f})
29812 RFC 4646 language code(s) for text/gemini documents. Optional.
29814 @item @code{silent?} (default: @code{#f})
29815 Set to @code{#t} to disable logging output.
29817 @item @code{serve-secret?} (default: @code{#f})
29818 Set to @code{#t} to serve secret files (files/directories starting with
29821 @item @code{log-ip?} (default: @code{#t})
29822 Whether or not to output IP addresses when logging.
29824 @item @code{user} (default: @code{"agate"})
29825 Owner of the @code{agate} process.
29827 @item @code{group} (default: @code{"agate"})
29828 Owner's group of the @code{agate} process.
29830 @item @code{log-file} (default: @file{"/var/log/agate.log"})
29831 The file which should store the logging output of Agate.
29836 @node Certificate Services
29837 @subsection Certificate Services
29840 @cindex HTTP, HTTPS
29841 @cindex Let's Encrypt
29842 @cindex TLS certificates
29843 The @code{(gnu services certbot)} module provides a service to
29844 automatically obtain a valid TLS certificate from the Let's Encrypt
29845 certificate authority. These certificates can then be used to serve
29846 content securely over HTTPS or other TLS-based protocols, with the
29847 knowledge that the client will be able to verify the server's
29850 @url{https://letsencrypt.org/, Let's Encrypt} provides the
29851 @code{certbot} tool to automate the certification process. This tool
29852 first securely generates a key on the server. It then makes a request
29853 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
29854 checks that the request originates from the host in question by using a
29855 challenge-response protocol, requiring the server to provide its
29856 response over HTTP@. If that protocol completes successfully, the CA
29857 signs the key, resulting in a certificate. That certificate is valid
29858 for a limited period of time, and therefore to continue to provide TLS
29859 services, the server needs to periodically ask the CA to renew its
29862 The certbot service automates this process: the initial key
29863 generation, the initial certification request to the Let's Encrypt
29864 service, the web server challenge/response integration, writing the
29865 certificate to disk, the automated periodic renewals, and the deployment
29866 tasks associated with the renewal (e.g.@: reloading services, copying keys
29867 with different permissions).
29869 Certbot is run twice a day, at a random minute within the hour. It
29870 won't do anything until your certificates are due for renewal or
29871 revoked, but running it regularly would give your service a chance of
29872 staying online in case a Let's Encrypt-initiated revocation happened for
29875 By using this service, you agree to the ACME Subscriber Agreement, which
29876 can be found there:
29877 @url{https://acme-v01.api.letsencrypt.org/directory}.
29879 @defvr {Scheme Variable} certbot-service-type
29880 A service type for the @code{certbot} Let's Encrypt client. Its value
29881 must be a @code{certbot-configuration} record as in this example:
29884 (define %nginx-deploy-hook
29886 "nginx-deploy-hook"
29887 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
29888 (kill pid SIGHUP))))
29890 (service certbot-service-type
29891 (certbot-configuration
29892 (email "foo@@example.net")
29895 (certificate-configuration
29896 (domains '("example.net" "www.example.net"))
29897 (deploy-hook %nginx-deploy-hook))
29898 (certificate-configuration
29899 (domains '("bar.example.net")))))))
29902 See below for details about @code{certbot-configuration}.
29905 @deftp {Data Type} certbot-configuration
29906 Data type representing the configuration of the @code{certbot} service.
29907 This type has the following parameters:
29910 @item @code{package} (default: @code{certbot})
29911 The certbot package to use.
29913 @item @code{webroot} (default: @code{/var/www})
29914 The directory from which to serve the Let's Encrypt challenge/response
29917 @item @code{certificates} (default: @code{()})
29918 A list of @code{certificates-configuration}s for which to generate
29919 certificates and request signatures. Each certificate has a @code{name}
29920 and several @code{domains}.
29922 @item @code{email} (default: @code{#f})
29923 Optional email address used for registration and recovery contact.
29924 Setting this is encouraged as it allows you to receive important
29925 notifications about the account and issued certificates.
29927 @item @code{server} (default: @code{#f})
29928 Optional URL of ACME server. Setting this overrides certbot's default,
29929 which is the Let's Encrypt server.
29931 @item @code{rsa-key-size} (default: @code{2048})
29932 Size of the RSA key.
29934 @item @code{default-location} (default: @i{see below})
29935 The default @code{nginx-location-configuration}. Because @code{certbot}
29936 needs to be able to serve challenges and responses, it needs to be able
29937 to run a web server. It does so by extending the @code{nginx} web
29938 service with an @code{nginx-server-configuration} listening on the
29939 @var{domains} on port 80, and which has a
29940 @code{nginx-location-configuration} for the @code{/.well-known/} URI
29941 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
29942 these nginx configuration data types.
29944 Requests to other URL paths will be matched by the
29945 @code{default-location}, which if present is added to all
29946 @code{nginx-server-configuration}s.
29948 By default, the @code{default-location} will issue a redirect from
29949 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
29950 you to define what to serve on your site via @code{https}.
29952 Pass @code{#f} to not issue a default location.
29956 @deftp {Data Type} certificate-configuration
29957 Data type representing the configuration of a certificate.
29958 This type has the following parameters:
29961 @item @code{name} (default: @i{see below})
29962 This name is used by Certbot for housekeeping and in file paths; it
29963 doesn't affect the content of the certificate itself. To see
29964 certificate names, run @code{certbot certificates}.
29966 Its default is the first provided domain.
29968 @item @code{domains} (default: @code{()})
29969 The first domain provided will be the subject CN of the certificate, and
29970 all domains will be Subject Alternative Names on the certificate.
29972 @item @code{challenge} (default: @code{#f})
29973 The challenge type that has to be run by certbot. If @code{#f} is specified,
29974 default to the HTTP challenge. If a value is specified, defaults to the
29975 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
29976 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
29977 and gives Let's Encrypt permission to log the public IP address of the
29978 requesting machine.
29980 @item @code{csr} (default: @code{#f})
29981 File name of Certificate Signing Request (CSR) in DER or PEM format.
29982 If @code{#f} is specified, this argument will not be passed to certbot.
29983 If a value is specified, certbot will use it to obtain a certificate, instead of
29984 using a self-generated CSR.
29985 The domain-name(s) mentioned in @code{domains}, must be consistent with the
29986 domain-name(s) mentioned in CSR file.
29988 @item @code{authentication-hook} (default: @code{#f})
29989 Command to be run in a shell once for each certificate challenge to be
29990 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
29991 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
29992 contains the validation string and @code{$CERTBOT_TOKEN} contains the
29993 file name of the resource requested when performing an HTTP-01 challenge.
29995 @item @code{cleanup-hook} (default: @code{#f})
29996 Command to be run in a shell once for each certificate challenge that
29997 have been answered by the @code{auth-hook}. For this command, the shell
29998 variables available in the @code{auth-hook} script are still available, and
29999 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
30000 of the @code{auth-hook} script.
30002 @item @code{deploy-hook} (default: @code{#f})
30003 Command to be run in a shell once for each successfully issued
30004 certificate. For this command, the shell variable
30005 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
30006 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
30007 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
30008 contain a space-delimited list of renewed certificate domains (for
30009 example, @samp{"example.com www.example.com"}.
30014 For each @code{certificate-configuration}, the certificate is saved to
30015 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
30016 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
30018 @subsection DNS Services
30019 @cindex DNS (domain name system)
30020 @cindex domain name system (DNS)
30022 The @code{(gnu services dns)} module provides services related to the
30023 @dfn{domain name system} (DNS). It provides a server service for hosting
30024 an @emph{authoritative} DNS server for multiple zones, slave or master.
30025 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
30026 caching and forwarding DNS server for the LAN, which uses
30027 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
30029 @subsubheading Knot Service
30031 An example configuration of an authoritative server for two zones, one master
30035 (define-zone-entries example.org.zone
30036 ;; Name TTL Class Type Data
30037 ("@@" "" "IN" "A" "127.0.0.1")
30038 ("@@" "" "IN" "NS" "ns")
30039 ("ns" "" "IN" "A" "127.0.0.1"))
30041 (define master-zone
30042 (knot-zone-configuration
30043 (domain "example.org")
30045 (origin "example.org")
30046 (entries example.org.zone)))))
30049 (knot-zone-configuration
30050 (domain "plop.org")
30051 (dnssec-policy "default")
30052 (master (list "plop-master"))))
30054 (define plop-master
30055 (knot-remote-configuration
30057 (address (list "208.76.58.171"))))
30061 (services (cons* (service knot-service-type
30062 (knot-configuration
30063 (remotes (list plop-master))
30064 (zones (list master-zone slave-zone))))
30069 @deffn {Scheme Variable} knot-service-type
30070 This is the type for the Knot DNS server.
30072 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
30073 zones, that is to say domain names you would buy from a registrar. This server
30074 is not a resolver, meaning that it can only resolve names for which it is
30075 authoritative. This server can be configured to serve zones as a master server
30076 or a slave server as a per-zone basis. Slave zones will get their data from
30077 masters, and will serve it as an authoritative server. From the point of view
30078 of a resolver, there is no difference between master and slave.
30080 The following data types are used to configure the Knot DNS server:
30083 @deftp {Data Type} knot-key-configuration
30084 Data type representing a key.
30085 This type has the following parameters:
30088 @item @code{id} (default: @code{""})
30089 An identifier for other configuration fields to refer to this key. IDs must
30090 be unique and must not be empty.
30092 @item @code{algorithm} (default: @code{#f})
30093 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
30094 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
30095 and @code{'hmac-sha512}.
30097 @item @code{secret} (default: @code{""})
30098 The secret key itself.
30103 @deftp {Data Type} knot-acl-configuration
30104 Data type representing an Access Control List (ACL) configuration.
30105 This type has the following parameters:
30108 @item @code{id} (default: @code{""})
30109 An identifier for other configuration fields to refer to this key. IDs must be
30110 unique and must not be empty.
30112 @item @code{address} (default: @code{'()})
30113 An ordered list of IP addresses, network subnets, or network ranges represented
30114 with strings. The query must match one of them. Empty value means that
30115 address match is not required.
30117 @item @code{key} (default: @code{'()})
30118 An ordered list of references to keys represented with strings. The string
30119 must match a key ID defined in a @code{knot-key-configuration}. No key means
30120 that a key is not require to match that ACL.
30122 @item @code{action} (default: @code{'()})
30123 An ordered list of actions that are permitted or forbidden by this ACL@. Possible
30124 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
30125 and @code{'update}.
30127 @item @code{deny?} (default: @code{#f})
30128 When true, the ACL defines restrictions. Listed actions are forbidden. When
30129 false, listed actions are allowed.
30134 @deftp {Data Type} zone-entry
30135 Data type representing a record entry in a zone file.
30136 This type has the following parameters:
30139 @item @code{name} (default: @code{"@@"})
30140 The name of the record. @code{"@@"} refers to the origin of the zone. Names
30141 are relative to the origin of the zone. For example, in the @code{example.org}
30142 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
30143 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
30144 refers to @code{ns.example.org}.
30146 @item @code{ttl} (default: @code{""})
30147 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
30149 @item @code{class} (default: @code{"IN"})
30150 The class of the record. Knot currently supports only @code{"IN"} and
30151 partially @code{"CH"}.
30153 @item @code{type} (default: @code{"A"})
30154 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
30155 address), NS (Name Server) and MX (Mail eXchange). Many other types are
30158 @item @code{data} (default: @code{""})
30159 The data contained in the record. For instance an IP address associated with
30160 an A record, or a domain name associated with an NS record. Remember that
30161 domain names are relative to the origin unless they end with a dot.
30166 @deftp {Data Type} zone-file
30167 Data type representing the content of a zone file.
30168 This type has the following parameters:
30171 @item @code{entries} (default: @code{'()})
30172 The list of entries. The SOA record is taken care of, so you don't need to
30173 put it in the list of entries. This list should probably contain an entry
30174 for your primary authoritative DNS server. Other than using a list of entries
30175 directly, you can use @code{define-zone-entries} to define a object containing
30176 the list of entries more easily, that you can later pass to the @code{entries}
30177 field of the @code{zone-file}.
30179 @item @code{origin} (default: @code{""})
30180 The name of your zone. This parameter cannot be empty.
30182 @item @code{ns} (default: @code{"ns"})
30183 The domain of your primary authoritative DNS server. The name is relative to
30184 the origin, unless it ends with a dot. It is mandatory that this primary
30185 DNS server corresponds to an NS record in the zone and that it is associated
30186 to an IP address in the list of entries.
30188 @item @code{mail} (default: @code{"hostmaster"})
30189 An email address people can contact you at, as the owner of the zone. This
30190 is translated as @code{<mail>@@<origin>}.
30192 @item @code{serial} (default: @code{1})
30193 The serial number of the zone. As this is used to keep track of changes by
30194 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
30195 Always increment it when you make a change in your zone.
30197 @item @code{refresh} (default: @code{(* 2 24 3600)})
30198 The frequency at which slaves will do a zone transfer. This value is a number
30199 of seconds. It can be computed by multiplications or with
30200 @code{(string->duration)}.
30202 @item @code{retry} (default: @code{(* 15 60)})
30203 The period after which a slave will retry to contact its master when it fails
30204 to do so a first time.
30206 @item @code{expiry} (default: @code{(* 14 24 3600)})
30207 Default TTL of records. Existing records are considered correct for at most
30208 this amount of time. After this period, resolvers will invalidate their cache
30209 and check again that it still exists.
30211 @item @code{nx} (default: @code{3600})
30212 Default TTL of inexistent records. This delay is usually short because you want
30213 your new domains to reach everyone quickly.
30218 @deftp {Data Type} knot-remote-configuration
30219 Data type representing a remote configuration.
30220 This type has the following parameters:
30223 @item @code{id} (default: @code{""})
30224 An identifier for other configuration fields to refer to this remote. IDs must
30225 be unique and must not be empty.
30227 @item @code{address} (default: @code{'()})
30228 An ordered list of destination IP addresses. Addresses are tried in sequence.
30229 An optional port can be given with the @@ separator. For instance:
30230 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
30232 @item @code{via} (default: @code{'()})
30233 An ordered list of source IP addresses. An empty list will have Knot choose
30234 an appropriate source IP@. An optional port can be given with the @@ separator.
30235 The default is to choose at random.
30237 @item @code{key} (default: @code{#f})
30238 A reference to a key, that is a string containing the identifier of a key
30239 defined in a @code{knot-key-configuration} field.
30244 @deftp {Data Type} knot-keystore-configuration
30245 Data type representing a keystore to hold dnssec keys.
30246 This type has the following parameters:
30249 @item @code{id} (default: @code{""})
30250 The id of the keystore. It must not be empty.
30252 @item @code{backend} (default: @code{'pem})
30253 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
30255 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
30256 The configuration string of the backend. An example for the PKCS#11 is:
30257 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
30258 For the pem backend, the string represents a path in the file system.
30263 @deftp {Data Type} knot-policy-configuration
30264 Data type representing a dnssec policy. Knot DNS is able to automatically
30265 sign your zones. It can either generate and manage your keys automatically or
30266 use keys that you generate.
30268 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
30269 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
30270 zone. In order to be trusted, the KSK needs to be present in the parent zone
30271 (usually a top-level domain). If your registrar supports dnssec, you will
30272 have to send them your KSK's hash so they can add a DS record in their zone.
30273 This is not automated and need to be done each time you change your KSK.
30275 The policy also defines the lifetime of keys. Usually, ZSK can be changed
30276 easily and use weaker cryptographic functions (they use lower parameters) in
30277 order to sign records quickly, so they are changed often. The KSK however
30278 requires manual interaction with the registrar, so they are changed less often
30279 and use stronger parameters because they sign only one record.
30281 This type has the following parameters:
30284 @item @code{id} (default: @code{""})
30285 The id of the policy. It must not be empty.
30287 @item @code{keystore} (default: @code{"default"})
30288 A reference to a keystore, that is a string containing the identifier of a
30289 keystore defined in a @code{knot-keystore-configuration} field. The
30290 @code{"default"} identifier means the default keystore (a kasp database that
30291 was setup by this service).
30293 @item @code{manual?} (default: @code{#f})
30294 Whether the key management is manual or automatic.
30296 @item @code{single-type-signing?} (default: @code{#f})
30297 When @code{#t}, use the Single-Type Signing Scheme.
30299 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
30300 An algorithm of signing keys and issued signatures.
30302 @item @code{ksk-size} (default: @code{256})
30303 The length of the KSK@. Note that this value is correct for the default
30304 algorithm, but would be unsecure for other algorithms.
30306 @item @code{zsk-size} (default: @code{256})
30307 The length of the ZSK@. Note that this value is correct for the default
30308 algorithm, but would be unsecure for other algorithms.
30310 @item @code{dnskey-ttl} (default: @code{'default})
30311 The TTL value for DNSKEY records added into zone apex. The special
30312 @code{'default} value means same as the zone SOA TTL.
30314 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
30315 The period between ZSK publication and the next rollover initiation.
30317 @item @code{propagation-delay} (default: @code{(* 24 3600)})
30318 An extra delay added for each key rollover step. This value should be high
30319 enough to cover propagation of data from the master server to all slaves.
30321 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
30322 A validity period of newly issued signatures.
30324 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
30325 A period how long before a signature expiration the signature will be refreshed.
30327 @item @code{nsec3?} (default: @code{#f})
30328 When @code{#t}, NSEC3 will be used instead of NSEC.
30330 @item @code{nsec3-iterations} (default: @code{5})
30331 The number of additional times the hashing is performed.
30333 @item @code{nsec3-salt-length} (default: @code{8})
30334 The length of a salt field in octets, which is appended to the original owner
30335 name before hashing.
30337 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
30338 The validity period of newly issued salt field.
30343 @deftp {Data Type} knot-zone-configuration
30344 Data type representing a zone served by Knot.
30345 This type has the following parameters:
30348 @item @code{domain} (default: @code{""})
30349 The domain served by this configuration. It must not be empty.
30351 @item @code{file} (default: @code{""})
30352 The file where this zone is saved. This parameter is ignored by master zones.
30353 Empty means default location that depends on the domain name.
30355 @item @code{zone} (default: @code{(zone-file)})
30356 The content of the zone file. This parameter is ignored by slave zones. It
30357 must contain a zone-file record.
30359 @item @code{master} (default: @code{'()})
30360 A list of master remotes. When empty, this zone is a master. When set, this
30361 zone is a slave. This is a list of remotes identifiers.
30363 @item @code{ddns-master} (default: @code{#f})
30364 The main master. When empty, it defaults to the first master in the list of
30367 @item @code{notify} (default: @code{'()})
30368 A list of slave remote identifiers.
30370 @item @code{acl} (default: @code{'()})
30371 A list of acl identifiers.
30373 @item @code{semantic-checks?} (default: @code{#f})
30374 When set, this adds more semantic checks to the zone.
30376 @item @code{zonefile-sync} (default: @code{0})
30377 The delay between a modification in memory and on disk. 0 means immediate
30380 @item @code{zonefile-load} (default: @code{#f})
30381 The way the zone file contents are applied during zone load. Possible values
30385 @item @code{#f} for using the default value from Knot,
30386 @item @code{'none} for not using the zone file at all,
30387 @item @code{'difference} for computing the difference between already available
30388 contents and zone contents and applying it to the current zone contents,
30389 @item @code{'difference-no-serial} for the same as @code{'difference}, but
30390 ignoring the SOA serial in the zone file, while the server takes care of it
30392 @item @code{'whole} for loading zone contents from the zone file.
30395 @item @code{journal-content} (default: @code{#f})
30396 The way the journal is used to store zone and its changes. Possible values
30397 are @code{'none} to not use it at all, @code{'changes} to store changes and
30398 @code{'all} to store contents. @code{#f} does not set this option, so the
30399 default value from Knot is used.
30401 @item @code{max-journal-usage} (default: @code{#f})
30402 The maximum size for the journal on disk. @code{#f} does not set this option,
30403 so the default value from Knot is used.
30405 @item @code{max-journal-depth} (default: @code{#f})
30406 The maximum size of the history. @code{#f} does not set this option, so the
30407 default value from Knot is used.
30409 @item @code{max-zone-size} (default: @code{#f})
30410 The maximum size of the zone file. This limit is enforced for incoming
30411 transfer and updates. @code{#f} does not set this option, so the default
30412 value from Knot is used.
30414 @item @code{dnssec-policy} (default: @code{#f})
30415 A reference to a @code{knot-policy-configuration} record, or the special
30416 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
30419 @item @code{serial-policy} (default: @code{'increment})
30420 A policy between @code{'increment} and @code{'unixtime}.
30425 @deftp {Data Type} knot-configuration
30426 Data type representing the Knot configuration.
30427 This type has the following parameters:
30430 @item @code{knot} (default: @code{knot})
30433 @item @code{run-directory} (default: @code{"/var/run/knot"})
30434 The run directory. This directory will be used for pid file and sockets.
30436 @item @code{includes} (default: @code{'()})
30437 A list of strings or file-like objects denoting other files that must be
30438 included at the top of the configuration file.
30440 @cindex secrets, Knot service
30441 This can be used to manage secrets out-of-band. For example, secret
30442 keys may be stored in an out-of-band file not managed by Guix, and
30443 thus not visible in @file{/gnu/store}---e.g., you could store secret
30444 key configuration in @file{/etc/knot/secrets.conf} and add this file
30445 to the @code{includes} list.
30447 One can generate a secret tsig key (for nsupdate and zone transfers with the
30448 keymgr command from the knot package. Note that the package is not automatically
30449 installed by the service. The following example shows how to generate a new
30453 keymgr -t mysecret > /etc/knot/secrets.conf
30454 chmod 600 /etc/knot/secrets.conf
30457 Also note that the generated key will be named @var{mysecret}, so it is the
30458 name that needs to be used in the @var{key} field of the
30459 @code{knot-acl-configuration} record and in other places that need to refer
30462 It can also be used to add configuration not supported by this interface.
30464 @item @code{listen-v4} (default: @code{"0.0.0.0"})
30465 An ip address on which to listen.
30467 @item @code{listen-v6} (default: @code{"::"})
30468 An ip address on which to listen.
30470 @item @code{listen-port} (default: @code{53})
30471 A port on which to listen.
30473 @item @code{keys} (default: @code{'()})
30474 The list of knot-key-configuration used by this configuration.
30476 @item @code{acls} (default: @code{'()})
30477 The list of knot-acl-configuration used by this configuration.
30479 @item @code{remotes} (default: @code{'()})
30480 The list of knot-remote-configuration used by this configuration.
30482 @item @code{zones} (default: @code{'()})
30483 The list of knot-zone-configuration used by this configuration.
30488 @subsubheading Knot Resolver Service
30490 @deffn {Scheme Variable} knot-resolver-service-type
30491 This is the type of the knot resolver service, whose value should be
30492 an @code{knot-resolver-configuration} object as in this example:
30495 (service knot-resolver-service-type
30496 (knot-resolver-configuration
30497 (kresd-config-file (plain-file "kresd.conf" "
30498 net.listen('192.168.0.1', 5353)
30499 user('knot-resolver', 'knot-resolver')
30500 modules = @{ 'hints > iterate', 'stats', 'predict' @}
30501 cache.size = 100 * MB
30505 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
30508 @deftp {Data Type} knot-resolver-configuration
30509 Data type representing the configuration of knot-resolver.
30512 @item @code{package} (default: @var{knot-resolver})
30513 Package object of the knot DNS resolver.
30515 @item @code{kresd-config-file} (default: %kresd.conf)
30516 File-like object of the kresd configuration file to use, by default it
30517 will listen on @code{127.0.0.1} and @code{::1}.
30519 @item @code{garbage-collection-interval} (default: 1000)
30520 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
30526 @subsubheading Dnsmasq Service
30528 @deffn {Scheme Variable} dnsmasq-service-type
30529 This is the type of the dnsmasq service, whose value should be an
30530 @code{dnsmasq-configuration} object as in this example:
30533 (service dnsmasq-service-type
30534 (dnsmasq-configuration
30536 (servers '("192.168.1.1"))))
30540 @deftp {Data Type} dnsmasq-configuration
30541 Data type representing the configuration of dnsmasq.
30544 @item @code{package} (default: @var{dnsmasq})
30545 Package object of the dnsmasq server.
30547 @item @code{no-hosts?} (default: @code{#f})
30548 When true, don't read the hostnames in /etc/hosts.
30550 @item @code{port} (default: @code{53})
30551 The port to listen on. Setting this to zero completely disables DNS
30552 responses, leaving only DHCP and/or TFTP functions.
30554 @item @code{local-service?} (default: @code{#t})
30555 Accept DNS queries only from hosts whose address is on a local subnet,
30556 ie a subnet for which an interface exists on the server.
30558 @item @code{listen-addresses} (default: @code{'()})
30559 Listen on the given IP addresses.
30561 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
30562 The file to read the IP address of the upstream nameservers from.
30564 @item @code{no-resolv?} (default: @code{#f})
30565 When true, don't read @var{resolv-file}.
30567 @item @code{forward-private-reverse-lookup?} (default: @code{#t})
30568 When false, all reverse lookups for private IP ranges are answered with
30569 "no such domain" rather than being forwarded upstream.
30571 @item @code{query-servers-in-order?} (default: @code{#f})
30572 When true, dnsmasq queries the servers in the same order as they appear
30575 @item @code{servers} (default: @code{'()})
30576 Specify IP address of upstream servers directly.
30578 @item @code{addresses} (default: @code{'()})
30579 For each entry, specify an IP address to return for any host in the
30580 given domains. Queries in the domains are never forwarded and always
30581 replied to with the specified IP address.
30583 This is useful for redirecting hosts locally, for example:
30586 (service dnsmasq-service-type
30587 (dnsmasq-configuration
30589 '(; Redirect to a local web-server.
30590 "/example.org/127.0.0.1"
30591 ; Redirect subdomain to a specific IP.
30592 "/subdomain.example.org/192.168.1.42"))))
30595 Note that rules in @file{/etc/hosts} take precedence over this.
30597 @item @code{cache-size} (default: @code{150})
30598 Set the size of dnsmasq's cache. Setting the cache size to zero
30601 @item @code{negative-cache?} (default: @code{#t})
30602 When false, disable negative caching.
30604 @item @code{cpe-id} (default: @code{#f})
30605 If set, add a CPE (Customer-Premises Equipment) identifier to DNS
30606 queries which are forwarded upstream.
30608 @item @code{tftp-enable?} (default: @code{#f})
30609 Whether to enable the built-in TFTP server.
30611 @item @code{tftp-no-fail?} (default: @code{#f})
30612 If true, does not fail dnsmasq if the TFTP server could not start up.
30614 @item @code{tftp-single-port?} (default: @code{#f})
30615 Whether to use only one single port for TFTP.
30617 @item @code{tftp-secure?} (default: @code{#f})
30618 If true, only files owned by the user running the dnsmasq process are accessible.
30620 If dnsmasq is being run as root, different rules apply:
30621 @code{tftp-secure?} has no effect, but only files which have the
30622 world-readable bit set are accessible.
30624 @item @code{tftp-max} (default: @code{#f})
30625 If set, sets the maximal number of concurrent connections allowed.
30627 @item @code{tftp-mtu} (default: @code{#f})
30628 If set, sets the MTU for TFTP packets to that value.
30630 @item @code{tftp-no-blocksize?} (default: @code{#f})
30631 If true, stops the TFTP server from negotiating the blocksize with a client.
30633 @item @code{tftp-lowercase?} (default: @code{#f})
30634 Whether to convert all filenames in TFTP requests to lowercase.
30636 @item @code{tftp-port-range} (default: @code{#f})
30637 If set, fixes the dynamical ports (one per client) to the given range
30638 (@code{"<start>,<end>"}).
30640 @item @code{tftp-root} (default: @code{/var/empty,lo})
30641 Look for files to transfer using TFTP relative to the given directory.
30642 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
30643 getting outside the specified root. Absolute paths (starting with @samp{/}) are
30644 allowed, but they must be within the TFTP-root. If the optional interface
30645 argument is given, the directory is only used for TFTP requests via that
30648 @item @code{tftp-unique-root} (default: @code{#f})
30649 If set, add the IP or hardware address of the TFTP client as a path component
30650 on the end of the TFTP-root. Only valid if a TFTP root is set and the
30651 directory exists. Defaults to adding IP address (in standard dotted-quad
30654 For instance, if @option{--tftp-root} is @samp{/tftp} and client
30655 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
30656 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
30657 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
30658 append the MAC address instead, using lowercase zero padded digits
30659 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
30660 resolving MAC addresses is only possible if the client is in the local
30661 network or obtained a DHCP lease from dnsmasq.
30666 @subsubheading ddclient Service
30669 The ddclient service described below runs the ddclient daemon, which takes
30670 care of automatically updating DNS entries for service providers such as
30671 @uref{https://dyn.com/dns/, Dyn}.
30673 The following example show instantiates the service with its default
30677 (service ddclient-service-type)
30680 Note that ddclient needs to access credentials that are stored in a
30681 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
30682 @code{secret-file} below). You are expected to create this file manually, in
30683 an ``out-of-band'' fashion (you @emph{could} make this file part of the
30684 service configuration, for instance by using @code{plain-file}, but it will be
30685 world-readable @i{via} @file{/gnu/store}). See the examples in the
30686 @file{share/ddclient} directory of the @code{ddclient} package.
30688 @c %start of fragment
30690 Available @code{ddclient-configuration} fields are:
30692 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
30693 The ddclient package.
30697 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
30698 The period after which ddclient will retry to check IP and domain name.
30700 Defaults to @samp{300}.
30704 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
30705 Use syslog for the output.
30707 Defaults to @samp{#t}.
30711 @deftypevr {@code{ddclient-configuration} parameter} string mail
30714 Defaults to @samp{"root"}.
30718 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
30719 Mail failed update to user.
30721 Defaults to @samp{"root"}.
30725 @deftypevr {@code{ddclient-configuration} parameter} string pid
30726 The ddclient PID file.
30728 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
30732 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
30733 Enable SSL support.
30735 Defaults to @samp{#t}.
30739 @deftypevr {@code{ddclient-configuration} parameter} string user
30740 Specifies the user name or ID that is used when running ddclient
30743 Defaults to @samp{"ddclient"}.
30747 @deftypevr {@code{ddclient-configuration} parameter} string group
30748 Group of the user who will run the ddclient program.
30750 Defaults to @samp{"ddclient"}.
30754 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
30755 Secret file which will be appended to @file{ddclient.conf} file. This
30756 file contains credentials for use by ddclient. You are expected to
30757 create it manually.
30759 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
30763 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
30764 Extra options will be appended to @file{ddclient.conf} file.
30766 Defaults to @samp{()}.
30771 @c %end of fragment
30775 @subsection VPN Services
30776 @cindex VPN (virtual private network)
30777 @cindex virtual private network (VPN)
30779 The @code{(gnu services vpn)} module provides services related to
30780 @dfn{virtual private networks} (VPNs).
30782 @subsubheading Bitmask
30784 @defvr {Scheme Variable} bitmask-service-type
30785 A service type for the @uref{https://bitmask.net, Bitmask} VPN client. It makes
30786 the client available in the system and loads its polkit policy. Please note that
30787 the client expects an active polkit-agent, which is either run by your
30788 desktop-environment or should be run manually.
30791 @subsubheading OpenVPN
30793 It provides a @emph{client} service for your machine to connect to a
30794 VPN, and a @emph{server} service for your machine to host a VPN@.
30796 @deffn {Scheme Procedure} openvpn-client-service @
30797 [#:config (openvpn-client-configuration)]
30799 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
30802 @deffn {Scheme Procedure} openvpn-server-service @
30803 [#:config (openvpn-server-configuration)]
30805 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
30807 Both can be run simultaneously.
30810 @c %automatically generated documentation
30812 @deftp {Data Type} openvpn-client-configuration
30813 Available @code{openvpn-client-configuration} fields are:
30816 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30817 The OpenVPN package.
30819 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30820 The OpenVPN pid file.
30822 @item @code{proto} (default: @code{udp}) (type: proto)
30823 The protocol (UDP or TCP) used to open a channel between clients and
30826 @item @code{dev} (default: @code{tun}) (type: dev)
30827 The device type used to represent the VPN connection.
30829 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30830 The certificate authority to check connections against.
30832 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30833 The certificate of the machine the daemon is running on. It should be
30834 signed by the authority given in @code{ca}.
30836 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30837 The key of the machine the daemon is running on. It must be the key
30838 whose certificate is @code{cert}.
30840 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30841 Whether to use the lzo compression algorithm.
30843 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30844 Don't re-read key files across SIGUSR1 or --ping-restart.
30846 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30847 Don't close and reopen TUN/TAP device or run up/down scripts across
30848 SIGUSR1 or --ping-restart restarts.
30850 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30851 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30852 poll/epoll/select prior to the write operation.
30854 @item @code{verbosity} (default: @code{3}) (type: number)
30857 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-client)
30858 Add an additional layer of HMAC authentication on top of the TLS control
30859 channel to protect against DoS attacks.
30861 @item @code{auth-user-pass} (type: maybe-string)
30862 Authenticate with server using username/password. The option is a file
30863 containing username/password on 2 lines. Do not use a file-like object
30864 as it would be added to the store and readable by any user.
30866 @item @code{verify-key-usage?} (default: @code{#t}) (type: key-usage)
30867 Whether to check the server certificate has server usage extension.
30869 @item @code{bind?} (default: @code{#f}) (type: bind)
30870 Bind to a specific local port number.
30872 @item @code{resolv-retry?} (default: @code{#t}) (type: resolv-retry)
30873 Retry resolving server address.
30875 @item @code{remote} (default: @code{()}) (type: openvpn-remote-list)
30876 A list of remote servers to connect to.
30878 @deftp {Data Type} openvpn-remote-configuration
30879 Available @code{openvpn-remote-configuration} fields are:
30882 @item @code{name} (default: @code{"my-server"}) (type: string)
30885 @item @code{port} (default: @code{1194}) (type: number)
30886 Port number the server listens to.
30896 @c %end of automatic openvpn-client documentation
30898 @c %automatically generated documentation
30900 @deftp {Data Type} openvpn-server-configuration
30901 Available @code{openvpn-server-configuration} fields are:
30904 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30905 The OpenVPN package.
30907 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30908 The OpenVPN pid file.
30910 @item @code{proto} (default: @code{udp}) (type: proto)
30911 The protocol (UDP or TCP) used to open a channel between clients and
30914 @item @code{dev} (default: @code{tun}) (type: dev)
30915 The device type used to represent the VPN connection.
30917 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30918 The certificate authority to check connections against.
30920 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30921 The certificate of the machine the daemon is running on. It should be
30922 signed by the authority given in @code{ca}.
30924 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30925 The key of the machine the daemon is running on. It must be the key
30926 whose certificate is @code{cert}.
30928 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30929 Whether to use the lzo compression algorithm.
30931 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30932 Don't re-read key files across SIGUSR1 or --ping-restart.
30934 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30935 Don't close and reopen TUN/TAP device or run up/down scripts across
30936 SIGUSR1 or --ping-restart restarts.
30938 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30939 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30940 poll/epoll/select prior to the write operation.
30942 @item @code{verbosity} (default: @code{3}) (type: number)
30945 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-server)
30946 Add an additional layer of HMAC authentication on top of the TLS control
30947 channel to protect against DoS attacks.
30949 @item @code{port} (default: @code{1194}) (type: number)
30950 Specifies the port number on which the server listens.
30952 @item @code{server} (default: @code{"10.8.0.0 255.255.255.0"}) (type: ip-mask)
30953 An ip and mask specifying the subnet inside the virtual network.
30955 @item @code{server-ipv6} (default: @code{#f}) (type: cidr6)
30956 A CIDR notation specifying the IPv6 subnet inside the virtual network.
30958 @item @code{dh} (default: @code{"/etc/openvpn/dh2048.pem"}) (type: string)
30959 The Diffie-Hellman parameters file.
30961 @item @code{ifconfig-pool-persist} (default: @code{"/etc/openvpn/ipp.txt"}) (type: string)
30962 The file that records client IPs.
30964 @item @code{redirect-gateway?} (default: @code{#f}) (type: gateway)
30965 When true, the server will act as a gateway for its clients.
30967 @item @code{client-to-client?} (default: @code{#f}) (type: boolean)
30968 When true, clients are allowed to talk to each other inside the VPN.
30970 @item @code{keepalive} (default: @code{(10 120)}) (type: keepalive)
30971 Causes ping-like messages to be sent back and forth over the link so
30972 that each side knows when the other side has gone down. @code{keepalive}
30973 requires a pair. The first element is the period of the ping sending,
30974 and the second element is the timeout before considering the other side
30977 @item @code{max-clients} (default: @code{100}) (type: number)
30978 The maximum number of clients.
30980 @item @code{status} (default: @code{"/var/run/openvpn/status"}) (type: string)
30981 The status file. This file shows a small report on current connection.
30982 It is truncated and rewritten every minute.
30984 @item @code{client-config-dir} (default: @code{()}) (type: openvpn-ccd-list)
30985 The list of configuration for some clients.
30991 @c %end of automatic openvpn-server documentation
30993 @subheading strongSwan
30995 Currently, the strongSwan service only provides legacy-style configuration with
30996 @file{ipsec.conf} and @file{ipsec.secrets} files.
30998 @defvr {Scheme Variable} strongswan-service-type
30999 A service type for configuring strongSwan for IPsec @acronym{VPN,
31000 Virtual Private Networking}. Its value must be a
31001 @code{strongswan-configuration} record as in this example:
31004 (service strongswan-service-type
31005 (strongswan-configuration
31006 (ipsec-conf "/etc/ipsec.conf")
31007 (ipsec-secrets "/etc/ipsec.secrets")))
31012 @deftp {Data Type} strongswan-configuration
31013 Data type representing the configuration of the StrongSwan service.
31016 @item @code{strongswan}
31017 The strongSwan package to use for this service.
31019 @item @code{ipsec-conf} (default: @code{#f})
31020 The file name of your @file{ipsec.conf}. If not @code{#f}, then this and
31021 @code{ipsec-secrets} must both be strings.
31023 @item @code{ipsec-secrets} (default @code{#f})
31024 The file name of your @file{ipsec.secrets}. If not @code{#f}, then this and
31025 @code{ipsec-conf} must both be strings.
31030 @subsubheading Wireguard
31032 @defvr {Scheme Variable} wireguard-service-type
31033 A service type for a Wireguard tunnel interface. Its value must be a
31034 @code{wireguard-configuration} record as in this example:
31037 (service wireguard-service-type
31038 (wireguard-configuration
31043 (endpoint "my.wireguard.com:51820")
31044 (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
31045 (allowed-ips '("10.0.0.2/32")))))))
31050 @deftp {Data Type} wireguard-configuration
31051 Data type representing the configuration of the Wireguard service.
31054 @item @code{wireguard}
31055 The wireguard package to use for this service.
31057 @item @code{interface} (default: @code{"wg0"})
31058 The interface name for the VPN.
31060 @item @code{addresses} (default: @code{'("10.0.0.1/32")})
31061 The IP addresses to be assigned to the above interface.
31063 @item @code{port} (default: @code{51820})
31064 The port on which to listen for incoming connections.
31066 @item @code{dns} (default: @code{#f})
31067 The DNS server(s) to announce to VPN clients via DHCP.
31069 @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
31070 The private key file for the interface. It is automatically generated if
31071 the file does not exist.
31073 @item @code{peers} (default: @code{'()})
31074 The authorized peers on this interface. This is a list of
31075 @var{wireguard-peer} records.
31080 @deftp {Data Type} wireguard-peer
31081 Data type representing a Wireguard peer attached to a given interface.
31087 @item @code{endpoint} (default: @code{#f})
31088 The optional endpoint for the peer, such as
31089 @code{"demo.wireguard.com:51820"}.
31091 @item @code{public-key}
31092 The peer public-key represented as a base64 string.
31094 @item @code{allowed-ips}
31095 A list of IP addresses from which incoming traffic for this peer is
31096 allowed and to which incoming traffic for this peer is directed.
31098 @item @code{keep-alive} (default: @code{#f})
31099 An optional time interval in seconds. A packet will be sent to the
31100 server endpoint once per time interval. This helps receiving
31101 incoming connections from this peer when you are behind a NAT or
31107 @node Network File System
31108 @subsection Network File System
31111 The @code{(gnu services nfs)} module provides the following services,
31112 which are most commonly used in relation to mounting or exporting
31113 directory trees as @dfn{network file systems} (NFS).
31115 While it is possible to use the individual components that together make
31116 up a Network File System service, we recommended to configure an NFS
31117 server with the @code{nfs-service-type}.
31119 @subsubheading NFS Service
31120 @cindex NFS, server
31122 The NFS service takes care of setting up all NFS component services,
31123 kernel configuration file systems, and installs configuration files in
31124 the locations that NFS expects.
31126 @defvr {Scheme Variable} nfs-service-type
31127 A service type for a complete NFS server.
31130 @deftp {Data Type} nfs-configuration
31131 This data type represents the configuration of the NFS service and all
31134 It has the following parameters:
31136 @item @code{nfs-utils} (default: @code{nfs-utils})
31137 The nfs-utils package to use.
31139 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
31140 If a list of string values is provided, the @command{rpc.nfsd} daemon
31141 will be limited to supporting the given versions of the NFS protocol.
31143 @item @code{exports} (default: @code{'()})
31144 This is a list of directories the NFS server should export. Each entry
31145 is a list consisting of two elements: a directory name and a string
31146 containing all options. This is an example in which the directory
31147 @file{/export} is served to all NFS clients as a read-only share:
31153 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
31156 @item @code{rpcmountd-port} (default: @code{#f})
31157 The network port that the @command{rpc.mountd} daemon should use.
31159 @item @code{rpcstatd-port} (default: @code{#f})
31160 The network port that the @command{rpc.statd} daemon should use.
31162 @item @code{rpcbind} (default: @code{rpcbind})
31163 The rpcbind package to use.
31165 @item @code{idmap-domain} (default: @code{"localdomain"})
31166 The local NFSv4 domain name.
31168 @item @code{nfsd-port} (default: @code{2049})
31169 The network port that the @command{nfsd} daemon should use.
31171 @item @code{nfsd-threads} (default: @code{8})
31172 The number of threads used by the @command{nfsd} daemon.
31174 @item @code{nfsd-tcp?} (default: @code{#t})
31175 Whether the @command{nfsd} daemon should listen on a TCP socket.
31177 @item @code{nfsd-udp?} (default: @code{#f})
31178 Whether the @command{nfsd} daemon should listen on a UDP socket.
31180 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31181 The directory where the pipefs file system is mounted.
31183 @item @code{debug} (default: @code{'()"})
31184 A list of subsystems for which debugging output should be enabled. This
31185 is a list of symbols. Any of these symbols are valid: @code{nfsd},
31186 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
31190 If you don't need a complete NFS service or prefer to build it yourself
31191 you can use the individual component services that are documented below.
31193 @subsubheading RPC Bind Service
31196 The RPC Bind service provides a facility to map program numbers into
31197 universal addresses.
31198 Many NFS related services use this facility. Hence it is automatically
31199 started when a dependent service starts.
31201 @defvr {Scheme Variable} rpcbind-service-type
31202 A service type for the RPC portmapper daemon.
31206 @deftp {Data Type} rpcbind-configuration
31207 Data type representing the configuration of the RPC Bind Service.
31208 This type has the following parameters:
31210 @item @code{rpcbind} (default: @code{rpcbind})
31211 The rpcbind package to use.
31213 @item @code{warm-start?} (default: @code{#t})
31214 If this parameter is @code{#t}, then the daemon will read a
31215 state file on startup thus reloading state information saved by a previous
31221 @subsubheading Pipefs Pseudo File System
31225 The pipefs file system is used to transfer NFS related data
31226 between the kernel and user space programs.
31228 @defvr {Scheme Variable} pipefs-service-type
31229 A service type for the pipefs pseudo file system.
31232 @deftp {Data Type} pipefs-configuration
31233 Data type representing the configuration of the pipefs pseudo file system service.
31234 This type has the following parameters:
31236 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31237 The directory to which the file system is to be attached.
31242 @subsubheading GSS Daemon Service
31245 @cindex global security system
31247 The @dfn{global security system} (GSS) daemon provides strong security for RPC
31249 Before exchanging RPC requests an RPC client must establish a security
31250 context. Typically this is done using the Kerberos command @command{kinit}
31251 or automatically at login time using PAM services (@pxref{Kerberos Services}).
31253 @defvr {Scheme Variable} gss-service-type
31254 A service type for the Global Security System (GSS) daemon.
31257 @deftp {Data Type} gss-configuration
31258 Data type representing the configuration of the GSS daemon service.
31259 This type has the following parameters:
31261 @item @code{nfs-utils} (default: @code{nfs-utils})
31262 The package in which the @command{rpc.gssd} command is to be found.
31264 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31265 The directory where the pipefs file system is mounted.
31271 @subsubheading IDMAP Daemon Service
31273 @cindex name mapper
31275 The idmap daemon service provides mapping between user IDs and user names.
31276 Typically it is required in order to access file systems mounted via NFSv4.
31278 @defvr {Scheme Variable} idmap-service-type
31279 A service type for the Identity Mapper (IDMAP) daemon.
31282 @deftp {Data Type} idmap-configuration
31283 Data type representing the configuration of the IDMAP daemon service.
31284 This type has the following parameters:
31286 @item @code{nfs-utils} (default: @code{nfs-utils})
31287 The package in which the @command{rpc.idmapd} command is to be found.
31289 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31290 The directory where the pipefs file system is mounted.
31292 @item @code{domain} (default: @code{#f})
31293 The local NFSv4 domain name.
31294 This must be a string or @code{#f}.
31295 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
31297 @item @code{verbosity} (default: @code{0})
31298 The verbosity level of the daemon.
31303 @node Samba Services, Continuous Integration, Network File System, Services
31304 @subsection Samba Services
31308 The @code{(gnu services samba)} module provides service definitions for
31309 Samba as well as additional helper services. Currently it provides the
31310 following services.
31312 @subsubheading Samba
31314 @uref{https://www.samba.org, Samba} provides network shares for folders
31315 and printers using the SMB/CIFS protocol commonly used on Windows. It
31316 can also act as an Active Directory Domain Controller (AD DC) for other
31317 hosts in an heterougenious network with different types of Computer
31320 @defvar {Scheme variable} samba-service-type
31322 The service type to enable the samba services @code{samba}, @code{nmbd},
31323 @code{smbd} and @code{winbindd}. By default this service type does not
31324 run as an AD DC, hence @code{samba} remains disabled.
31328 @deftp{Data Type} samba-service-configuration
31329 Configuration record for the Samba suite.
31332 @item @code{package} (default: @code{samba})
31333 The samba package to use.
31335 @item @code{config-file} (default: @code{#f})
31336 The config file to use.
31338 @item @code{enable-samba?} (default: @code{#f})
31339 Manually enable the @code{samba} daemon.
31341 @item @code{enable-smbd?} (default: @code{#f})
31342 Manually enable the @code{smbd} daemon.
31344 @item @code{enable-nmbd?} (default: @code{#f})
31345 Manually enable the @code{nmbd} daemon.
31347 @item @code{enable-winbindd?} (default: @code{#f})
31348 Manually enable the @code{winbindd} daemon.
31354 @subsubheading Web Service Discovery Daemon
31356 Web Service Discovery Daemon implements
31357 @uref{http://docs.oasis-open.org/ws-dd/discovery/1.1/os/wsdd-discovery-1.1-spec-os.html,
31358 Web Services Dynamic Discovery} protocol that enables host discovery --
31359 similar to Avahi -- over Multicast DNS. It is a drop-in replacement for
31360 SMB hosts that have had SMBv1 disabled for security reasons.
31362 @defvr {Scheme Variable} wsdd-service-type
31364 Service type for the WSD host daemon. The value for
31365 this service type is a @code{wsdd-configuration} record. The details
31366 for the @code{wsdd-configuration} record type are given below.
31369 @deftp{Data Type} wsdd-configuration This data type represents the
31370 configuration for the wsdd service.
31374 @item @code{package} (default: @code{wsdd})
31375 The wsdd package to use.
31377 @item @code{ipv4only?} (default: @code{#f})
31378 Only listen to IPv4 addresses.
31380 @item @code{ipv6only} (default: @code{#f})
31381 Only listen to IPv6 addresses. Please note: Activating both options is
31382 not possible, since there would be no IP versions to listen to.
31384 @item @code{chroot} (default: @code{#f})
31385 Chroot into a separate directory to prevent access to other directories.
31386 This is to increase security in case there is a vulnerability in
31389 @item @code{hop-limit} (default: @code{1})
31390 Limit to the level of hops for multicast packets. The default is
31391 @var{1} which should prevent packets from leaving the local network.
31393 @item @code{interface} (default: @code{'()})
31394 Limit to the given list of interfaces to listen to. By default wsdd
31395 will listen to all interfaces. Except the loopback interface is never
31398 @item @code{uuid-device} (default: @code{#f})
31399 The WSD protocol requires a device to have a UUID. Set this to manually
31400 assign the service a UUID.
31402 @item @code{domain} (default: @code{#f})
31403 Notify this host is a member of an Active Directory.
31405 @item @code{host-name} (default: @code{#f})
31406 Manually set the hostname rather than letting @command{wsdd} inherit
31407 this host's hostname. Only the host name part of a possible FQDN will
31408 be used in the default case.
31410 @item @code{preserve-case?} (default: @code{#f})
31411 By default @command{wsdd} will convert the hostname in workgroup to all
31412 uppercase. The opposite is true for hostnames in domains. Setting this
31413 parameter will preserve case.
31415 @item @code{workgroup} (default: @var{"WORKGROUP"})
31416 Change the name of the workgroup. By default @command{wsdd} reports
31417 this host being member of a workgroup.
31422 @node Continuous Integration
31423 @subsection Continuous Integration
31425 @cindex continuous integration
31426 @uref{https://guix.gnu.org/cuirass/, Cuirass} is a continuous
31427 integration tool for Guix. It can be used both for development and for
31428 providing substitutes to others (@pxref{Substitutes}).
31430 The @code{(gnu services cuirass)} module provides the following service.
31432 @defvr {Scheme Procedure} cuirass-service-type
31433 The type of the Cuirass service. Its value must be a
31434 @code{cuirass-configuration} object, as described below.
31437 To add build jobs, you have to set the @code{specifications} field of
31438 the configuration. For instance, the following example will build all
31439 the packages provided by the @code{my-channel} channel.
31442 (define %cuirass-specs
31443 #~(list (specification
31444 (name "my-channel")
31445 (build '(channels my-channel))
31449 (url "https://my-channel.git"))
31450 %default-channels)))))
31452 (service cuirass-service-type
31453 (cuirass-configuration
31454 (specifications %cuirass-specs)))
31457 To build the @code{linux-libre} package defined by the default Guix
31458 channel, one can use the following configuration.
31461 (define %cuirass-specs
31462 #~(list (specification
31464 (build '(packages "linux-libre")))))
31466 (service cuirass-service-type
31467 (cuirass-configuration
31468 (specifications %cuirass-specs)))
31471 The other configuration possibilities, as well as the specification
31472 record itself are described in the Cuirass manual
31473 (@pxref{Specifications,,, cuirass, Cuirass}).
31475 While information related to build jobs is located directly in the
31476 specifications, global settings for the @command{cuirass} process are
31477 accessible in other @code{cuirass-configuration} fields.
31479 @deftp {Data Type} cuirass-configuration
31480 Data type representing the configuration of Cuirass.
31483 @item @code{cuirass} (default: @code{cuirass})
31484 The Cuirass package to use.
31486 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
31487 Location of the log file.
31489 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
31490 Location of the log file used by the web interface.
31492 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
31493 Location of the repository cache.
31495 @item @code{user} (default: @code{"cuirass"})
31496 Owner of the @code{cuirass} process.
31498 @item @code{group} (default: @code{"cuirass"})
31499 Owner's group of the @code{cuirass} process.
31501 @item @code{interval} (default: @code{60})
31502 Number of seconds between the poll of the repositories followed by the
31505 @item @code{parameters} (default: @code{#f})
31506 Read parameters from the given @var{parameters} file. The supported
31507 parameters are described here (@pxref{Parameters,,, cuirass, Cuirass}).
31509 @item @code{remote-server} (default: @code{#f})
31510 A @code{cuirass-remote-server-configuration} record to use the build
31511 remote mechanism or @code{#f} to use the default build mechanism.
31513 @item @code{database} (default: @code{"dbname=cuirass host=/var/run/postgresql"})
31514 Use @var{database} as the database containing the jobs and the past
31515 build results. Since Cuirass uses PostgreSQL as a database engine,
31516 @var{database} must be a string such as @code{"dbname=cuirass
31519 @item @code{port} (default: @code{8081})
31520 Port number used by the HTTP server.
31522 @item @code{host} (default: @code{"localhost"})
31523 Listen on the network interface for @var{host}. The default is to
31524 accept connections from localhost.
31526 @item @code{specifications} (default: @code{#~'()})
31527 A gexp (@pxref{G-Expressions}) that evaluates to a list of
31528 specifications records. The specification record is described in the
31529 Cuirass manual (@pxref{Specifications,,, cuirass, Cuirass}).
31531 @item @code{use-substitutes?} (default: @code{#f})
31532 This allows using substitutes to avoid building every dependencies of a job
31535 @item @code{one-shot?} (default: @code{#f})
31536 Only evaluate specifications and build derivations once.
31538 @item @code{fallback?} (default: @code{#f})
31539 When substituting a pre-built binary fails, fall back to building
31542 @item @code{extra-options} (default: @code{'()})
31543 Extra options to pass when running the Cuirass processes.
31548 @cindex remote build
31549 @subsubheading Cuirass remote building
31551 Cuirass supports two mechanisms to build derivations.
31554 @item Using the local Guix daemon.
31555 This is the default build mechanism. Once the build jobs are
31556 evaluated, they are sent to the local Guix daemon. Cuirass then
31557 listens to the Guix daemon output to detect the various build events.
31559 @item Using the remote build mechanism.
31560 The build jobs are not submitted to the local Guix daemon. Instead, a
31561 remote server dispatches build requests to the connect remote workers,
31562 according to the build priorities.
31566 To enable this build mode a @code{cuirass-remote-server-configuration}
31567 record must be passed as @code{remote-server} argument of the
31568 @code{cuirass-configuration} record. The
31569 @code{cuirass-remote-server-configuration} record is described below.
31571 This build mode scales way better than the default build mode. This is
31572 the build mode that is used on the GNU Guix build farm at
31573 @url{https://ci.guix.gnu.org}. It should be preferred when using
31574 Cuirass to build large amount of packages.
31576 @deftp {Data Type} cuirass-remote-server-configuration
31577 Data type representing the configuration of the Cuirass remote-server.
31580 @item @code{backend-port} (default: @code{5555})
31581 The TCP port for communicating with @code{remote-worker} processes
31582 using ZMQ. It defaults to @code{5555}.
31584 @item @code{log-port} (default: @code{5556})
31585 The TCP port of the log server. It defaults to @code{5556}.
31587 @item @code{publish-port} (default: @code{5557})
31588 The TCP port of the publish server. It defaults to @code{5557}.
31590 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-server.log"})
31591 Location of the log file.
31593 @item @code{cache} (default: @code{"/var/cache/cuirass/remote"})
31594 Use @var{cache} directory to cache build log files.
31596 @item @code{trigger-url} (default: @code{#f})
31597 Once a substitute is successfully fetched, trigger substitute baking at
31600 @item @code{publish?} (default: @code{#t})
31601 If set to false, do not start a publish server and ignore the
31602 @code{publish-port} argument. This can be useful if there is already a
31603 standalone publish server standing next to the remote server.
31605 @item @code{public-key}
31606 @item @code{private-key}
31607 Use the specific @var{file}s as the public/private key pair used to sign
31608 the store items being published.
31613 At least one remote worker must also be started on any machine of the
31614 local network to actually perform the builds and report their status.
31616 @deftp {Data Type} cuirass-remote-worker-configuration
31617 Data type representing the configuration of the Cuirass remote-worker.
31620 @item @code{cuirass} (default: @code{cuirass})
31621 The Cuirass package to use.
31623 @item @code{workers} (default: @code{1})
31624 Start @var{workers} parallel workers.
31626 @item @code{server} (default: @code{#f})
31627 Do not use Avahi discovery and connect to the given @code{server} IP
31630 @item @code{systems} (default: @code{(list (%current-system))})
31631 Only request builds for the given @var{systems}.
31633 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-worker.log"})
31634 Location of the log file.
31636 @item @code{publish-port} (default: @code{5558})
31637 The TCP port of the publish server. It defaults to @code{5558}.
31639 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
31640 The list of URLs where to look for substitutes by default.
31642 @item @code{public-key}
31643 @item @code{private-key}
31644 Use the specific @var{file}s as the public/private key pair used to sign
31645 the store items being published.
31650 @subsubheading Laminar
31652 @uref{https://laminar.ohwg.net/, Laminar} is a lightweight and modular
31653 Continuous Integration service. It doesn't have a configuration web UI
31654 instead uses version-controllable configuration files and scripts.
31656 Laminar encourages the use of existing tools such as bash and cron
31657 instead of reinventing them.
31659 @defvr {Scheme Procedure} laminar-service-type
31660 The type of the Laminar service. Its value must be a
31661 @code{laminar-configuration} object, as described below.
31663 All configuration values have defaults, a minimal configuration to get
31664 Laminar running is shown below. By default, the web interface is
31665 available on port 8080.
31668 (service laminar-service-type)
31672 @deftp {Data Type} laminar-configuration
31673 Data type representing the configuration of Laminar.
31676 @item @code{laminar} (default: @code{laminar})
31677 The Laminar package to use.
31679 @item @code{home-directory} (default: @code{"/var/lib/laminar"})
31680 The directory for job configurations and run directories.
31682 @item @code{bind-http} (default: @code{"*:8080"})
31683 The interface/port or unix socket on which laminard should listen for
31684 incoming connections to the web frontend.
31686 @item @code{bind-rpc} (default: @code{"unix-abstract:laminar"})
31687 The interface/port or unix socket on which laminard should listen for
31688 incoming commands such as build triggers.
31690 @item @code{title} (default: @code{"Laminar"})
31691 The page title to show in the web frontend.
31693 @item @code{keep-rundirs} (default: @code{0})
31694 Set to an integer defining how many rundirs to keep per job. The
31695 lowest-numbered ones will be deleted. The default is 0, meaning all run
31696 dirs will be immediately deleted.
31698 @item @code{archive-url} (default: @code{#f})
31699 The web frontend served by laminard will use this URL to form links to
31700 artefacts archived jobs.
31702 @item @code{base-url} (default: @code{#f})
31703 Base URL to use for links to laminar itself.
31708 @node Power Management Services
31709 @subsection Power Management Services
31712 @cindex power management with TLP
31713 @subsubheading TLP daemon
31715 The @code{(gnu services pm)} module provides a Guix service definition
31716 for the Linux power management tool TLP.
31718 TLP enables various powersaving modes in userspace and kernel.
31719 Contrary to @code{upower-service}, it is not a passive,
31720 monitoring tool, as it will apply custom settings each time a new power
31721 source is detected. More information can be found at
31722 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
31724 @deffn {Scheme Variable} tlp-service-type
31725 The service type for the TLP tool. The default settings are optimised
31726 for battery life on most systems, but you can tweak them to your heart's
31727 content by adding a valid @code{tlp-configuration}:
31729 (service tlp-service-type
31731 (cpu-scaling-governor-on-ac (list "performance"))
31732 (sched-powersave-on-bat? #t)))
31736 Each parameter definition is preceded by its type; for example,
31737 @samp{boolean foo} indicates that the @code{foo} parameter should be
31738 specified as a boolean. Types starting with @code{maybe-} denote
31739 parameters that won't show up in TLP config file when their value is
31740 left unset, or is explicitly set to the @code{%unset-value} value.
31742 @c The following documentation was initially generated by
31743 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
31744 @c documentation is better, so we shouldn't hesitate to edit below as
31745 @c needed. However if the change you want to make to this documentation
31746 @c can be done in an automated way, it's probably easier to change
31747 @c (generate-documentation) than to make it below and have to deal with
31748 @c the churn as TLP updates.
31750 Available @code{tlp-configuration} fields are:
31752 @deftypevr {@code{tlp-configuration} parameter} package tlp
31757 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
31758 Set to true if you wish to enable TLP.
31760 Defaults to @samp{#t}.
31764 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
31765 Default mode when no power supply can be detected. Alternatives are AC
31768 Defaults to @samp{"AC"}.
31772 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
31773 Number of seconds Linux kernel has to wait after the disk goes idle,
31774 before syncing on AC.
31776 Defaults to @samp{0}.
31780 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
31781 Same as @code{disk-idle-ac} but on BAT mode.
31783 Defaults to @samp{2}.
31787 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
31788 Dirty pages flushing periodicity, expressed in seconds.
31790 Defaults to @samp{15}.
31794 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
31795 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
31797 Defaults to @samp{60}.
31801 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
31802 CPU frequency scaling governor on AC mode. With intel_pstate driver,
31803 alternatives are powersave and performance. With acpi-cpufreq driver,
31804 alternatives are ondemand, powersave, performance and conservative.
31806 Defaults to @samp{disabled}.
31810 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
31811 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
31813 Defaults to @samp{disabled}.
31817 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
31818 Set the min available frequency for the scaling governor on AC.
31820 Defaults to @samp{disabled}.
31824 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
31825 Set the max available frequency for the scaling governor on AC.
31827 Defaults to @samp{disabled}.
31831 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
31832 Set the min available frequency for the scaling governor on BAT.
31834 Defaults to @samp{disabled}.
31838 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
31839 Set the max available frequency for the scaling governor on BAT.
31841 Defaults to @samp{disabled}.
31845 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
31846 Limit the min P-state to control the power dissipation of the CPU, in AC
31847 mode. Values are stated as a percentage of the available performance.
31849 Defaults to @samp{disabled}.
31853 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
31854 Limit the max P-state to control the power dissipation of the CPU, in AC
31855 mode. Values are stated as a percentage of the available performance.
31857 Defaults to @samp{disabled}.
31861 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
31862 Same as @code{cpu-min-perf-on-ac} on BAT mode.
31864 Defaults to @samp{disabled}.
31868 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
31869 Same as @code{cpu-max-perf-on-ac} on BAT mode.
31871 Defaults to @samp{disabled}.
31875 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
31876 Enable CPU turbo boost feature on AC mode.
31878 Defaults to @samp{disabled}.
31882 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
31883 Same as @code{cpu-boost-on-ac?} on BAT mode.
31885 Defaults to @samp{disabled}.
31889 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
31890 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
31891 used under light load conditions.
31893 Defaults to @samp{#f}.
31897 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
31898 Same as @code{sched-powersave-on-ac?} but on BAT mode.
31900 Defaults to @samp{#t}.
31904 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
31905 Enable Linux kernel NMI watchdog.
31907 Defaults to @samp{#f}.
31911 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
31912 For Linux kernels with PHC patch applied, change CPU voltages. An
31913 example value would be @samp{"F:V F:V F:V F:V"}.
31915 Defaults to @samp{disabled}.
31919 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
31920 Set CPU performance versus energy saving policy on AC@. Alternatives are
31921 performance, normal, powersave.
31923 Defaults to @samp{"performance"}.
31927 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
31928 Same as @code{energy-perf-policy-ac} but on BAT mode.
31930 Defaults to @samp{"powersave"}.
31934 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
31939 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
31940 Hard disk advanced power management level.
31944 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
31945 Same as @code{disk-apm-bat} but on BAT mode.
31949 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
31950 Hard disk spin down timeout. One value has to be specified for each
31951 declared hard disk.
31953 Defaults to @samp{disabled}.
31957 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
31958 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
31960 Defaults to @samp{disabled}.
31964 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
31965 Select IO scheduler for disk devices. One value has to be specified for
31966 each declared hard disk. Example alternatives are cfq, deadline and
31969 Defaults to @samp{disabled}.
31973 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
31974 SATA aggressive link power management (ALPM) level. Alternatives are
31975 min_power, medium_power, max_performance.
31977 Defaults to @samp{"max_performance"}.
31981 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
31982 Same as @code{sata-linkpwr-ac} but on BAT mode.
31984 Defaults to @samp{"min_power"}.
31988 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
31989 Exclude specified SATA host devices for link power management.
31991 Defaults to @samp{disabled}.
31995 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
31996 Enable Runtime Power Management for AHCI controller and disks on AC
31999 Defaults to @samp{disabled}.
32003 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
32004 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
32006 Defaults to @samp{disabled}.
32010 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
32011 Seconds of inactivity before disk is suspended.
32013 Defaults to @samp{15}.
32017 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
32018 PCI Express Active State Power Management level. Alternatives are
32019 default, performance, powersave.
32021 Defaults to @samp{"performance"}.
32025 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
32026 Same as @code{pcie-aspm-ac} but on BAT mode.
32028 Defaults to @samp{"powersave"}.
32032 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat0
32033 Percentage when battery 0 should begin charging. Only supported on some laptops.
32035 Defaults to @samp{disabled}.
32039 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat0
32040 Percentage when battery 0 should stop charging. Only supported on some laptops.
32042 Defaults to @samp{disabled}.
32046 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat1
32047 Percentage when battery 1 should begin charging. Only supported on some laptops.
32049 Defaults to @samp{disabled}.
32053 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat1
32054 Percentage when battery 1 should stop charging. Only supported on some laptops.
32056 Defaults to @samp{disabled}.
32060 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
32061 Radeon graphics clock speed level. Alternatives are low, mid, high,
32064 Defaults to @samp{"high"}.
32068 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
32069 Same as @code{radeon-power-ac} but on BAT mode.
32071 Defaults to @samp{"low"}.
32075 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
32076 Radeon dynamic power management method (DPM). Alternatives are battery,
32079 Defaults to @samp{"performance"}.
32083 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
32084 Same as @code{radeon-dpm-state-ac} but on BAT mode.
32086 Defaults to @samp{"battery"}.
32090 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
32091 Radeon DPM performance level. Alternatives are auto, low, high.
32093 Defaults to @samp{"auto"}.
32097 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
32098 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
32100 Defaults to @samp{"auto"}.
32104 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
32105 Wifi power saving mode.
32107 Defaults to @samp{#f}.
32111 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
32112 Same as @code{wifi-power-ac?} but on BAT mode.
32114 Defaults to @samp{#t}.
32118 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
32119 Disable wake on LAN.
32121 Defaults to @samp{#t}.
32125 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
32126 Timeout duration in seconds before activating audio power saving on
32127 Intel HDA and AC97 devices. A value of 0 disables power saving.
32129 Defaults to @samp{0}.
32133 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
32134 Same as @code{sound-powersave-ac} but on BAT mode.
32136 Defaults to @samp{1}.
32140 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
32141 Disable controller in powersaving mode on Intel HDA devices.
32143 Defaults to @samp{#t}.
32147 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
32148 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
32149 powered on again by releasing (and reinserting) the eject lever or by
32150 pressing the disc eject button on newer models.
32152 Defaults to @samp{#f}.
32156 @deftypevr {@code{tlp-configuration} parameter} string bay-device
32157 Name of the optical drive device to power off.
32159 Defaults to @samp{"sr0"}.
32163 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
32164 Runtime Power Management for PCI(e) bus devices. Alternatives are on
32167 Defaults to @samp{"on"}.
32171 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
32172 Same as @code{runtime-pm-ac} but on BAT mode.
32174 Defaults to @samp{"auto"}.
32178 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
32179 Runtime Power Management for all PCI(e) bus devices, except blacklisted
32182 Defaults to @samp{#t}.
32186 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
32187 Exclude specified PCI(e) device addresses from Runtime Power Management.
32189 Defaults to @samp{disabled}.
32193 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
32194 Exclude PCI(e) devices assigned to the specified drivers from Runtime
32199 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
32200 Enable USB autosuspend feature.
32202 Defaults to @samp{#t}.
32206 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
32207 Exclude specified devices from USB autosuspend.
32209 Defaults to @samp{disabled}.
32213 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
32214 Exclude WWAN devices from USB autosuspend.
32216 Defaults to @samp{#t}.
32220 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
32221 Include specified devices into USB autosuspend, even if they are already
32222 excluded by the driver or via @code{usb-blacklist-wwan?}.
32224 Defaults to @samp{disabled}.
32228 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
32229 Enable USB autosuspend before shutdown.
32231 Defaults to @samp{disabled}.
32235 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
32236 Restore radio device state (bluetooth, wifi, wwan) from previous
32237 shutdown on system startup.
32239 Defaults to @samp{#f}.
32244 @cindex CPU frequency scaling with thermald
32245 @subsubheading Thermald daemon
32247 The @code{(gnu services pm)} module provides an interface to
32248 thermald, a CPU frequency scaling service which helps prevent overheating.
32250 @defvr {Scheme Variable} thermald-service-type
32251 This is the service type for
32252 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
32253 Thermal Daemon, which is responsible for controlling the thermal state
32254 of processors and preventing overheating.
32257 @deftp {Data Type} thermald-configuration
32258 Data type representing the configuration of @code{thermald-service-type}.
32261 @item @code{adaptive?} (default: @code{#f})
32262 Use @acronym{DPTF, Dynamic Power and Thermal Framework} adaptive tables
32265 @item @code{ignore-cpuid-check?} (default: @code{#f})
32266 Ignore cpuid check for supported CPU models.
32268 @item @code{thermald} (default: @var{thermald})
32269 Package object of thermald.
32274 @node Audio Services
32275 @subsection Audio Services
32277 The @code{(gnu services audio)} module provides a service to start MPD
32278 (the Music Player Daemon).
32281 @subsubheading Music Player Daemon
32283 The Music Player Daemon (MPD) is a service that can play music while
32284 being controlled from the local machine or over the network by a variety
32287 The following example shows how one might run @code{mpd} as user
32288 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
32291 (service mpd-service-type
32297 @defvr {Scheme Variable} mpd-service-type
32298 The service type for @command{mpd}
32301 @deftp {Data Type} mpd-configuration
32302 Data type representing the configuration of @command{mpd}.
32305 @item @code{user} (default: @code{"mpd"})
32306 The user to run mpd as.
32308 @item @code{music-dir} (default: @code{"~/Music"})
32309 The directory to scan for music files.
32311 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
32312 The directory to store playlists.
32314 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
32315 The location of the music database.
32317 @item @code{state-file} (default: @code{"~/.mpd/state"})
32318 The location of the file that stores current MPD's state.
32320 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
32321 The location of the sticker database.
32323 @item @code{port} (default: @code{"6600"})
32324 The port to run mpd on.
32326 @item @code{address} (default: @code{"any"})
32327 The address that mpd will bind to. To use a Unix domain socket,
32328 an absolute path can be specified here.
32330 @item @code{outputs} (default: @code{"(list (mpd-output))"})
32331 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
32336 @deftp {Data Type} mpd-output
32337 Data type representing an @command{mpd} audio output.
32340 @item @code{name} (default: @code{"MPD"})
32341 The name of the audio output.
32343 @item @code{type} (default: @code{"pulse"})
32344 The type of audio output.
32346 @item @code{enabled?} (default: @code{#t})
32347 Specifies whether this audio output is enabled when MPD is started. By
32348 default, all audio outputs are enabled. This is just the default
32349 setting when there is no state file; with a state file, the previous
32352 @item @code{tags?} (default: @code{#t})
32353 If set to @code{#f}, then MPD will not send tags to this output. This
32354 is only useful for output plugins that can receive tags, for example the
32355 @code{httpd} output plugin.
32357 @item @code{always-on?} (default: @code{#f})
32358 If set to @code{#t}, then MPD attempts to keep this audio output always
32359 open. This may be useful for streaming servers, when you don’t want to
32360 disconnect all listeners even when playback is accidentally stopped.
32362 @item @code{mixer-type}
32363 This field accepts a symbol that specifies which mixer should be used
32364 for this audio output: the @code{hardware} mixer, the @code{software}
32365 mixer, the @code{null} mixer (allows setting the volume, but with no
32366 effect; this can be used as a trick to implement an external mixer
32367 External Mixer) or no mixer (@code{none}).
32369 @item @code{extra-options} (default: @code{'()})
32370 An association list of option symbols to string values to be appended to
32371 the audio output configuration.
32376 The following example shows a configuration of @code{mpd} that provides
32377 an HTTP audio streaming output.
32380 (service mpd-service-type
32388 `((encoder . "vorbis")
32389 (port . "8080"))))))))
32393 @node Virtualization Services
32394 @subsection Virtualization Services
32396 The @code{(gnu services virtualization)} module provides services for
32397 the libvirt and virtlog daemons, as well as other virtualization-related
32400 @subsubheading Libvirt daemon
32402 @code{libvirtd} is the server side daemon component of the libvirt
32403 virtualization management system. This daemon runs on host servers
32404 and performs required management tasks for virtualized guests.
32406 @deffn {Scheme Variable} libvirt-service-type
32407 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
32408 Its value must be a @code{libvirt-configuration}.
32411 (service libvirt-service-type
32412 (libvirt-configuration
32413 (unix-sock-group "libvirt")
32414 (tls-port "16555")))
32418 @c Auto-generated with (generate-libvirt-documentation)
32419 Available @code{libvirt-configuration} fields are:
32421 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
32426 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
32427 Flag listening for secure TLS connections on the public TCP/IP port.
32428 You must set @code{listen} for this to have any effect.
32430 It is necessary to setup a CA and issue server certificates before using
32433 Defaults to @samp{#t}.
32437 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
32438 Listen for unencrypted TCP connections on the public TCP/IP port. You must
32439 set @code{listen} for this to have any effect.
32441 Using the TCP socket requires SASL authentication by default. Only SASL
32442 mechanisms which support data encryption are allowed. This is
32443 DIGEST_MD5 and GSSAPI (Kerberos5).
32445 Defaults to @samp{#f}.
32449 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
32450 Port for accepting secure TLS connections. This can be a port number,
32453 Defaults to @samp{"16514"}.
32457 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
32458 Port for accepting insecure TCP connections. This can be a port number,
32461 Defaults to @samp{"16509"}.
32465 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
32466 IP address or hostname used for client connections.
32468 Defaults to @samp{"0.0.0.0"}.
32472 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
32473 Flag toggling mDNS advertisement of the libvirt service.
32475 Alternatively can disable for all services on a host by stopping the
32478 Defaults to @samp{#f}.
32482 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
32483 Default mDNS advertisement name. This must be unique on the immediate
32486 Defaults to @samp{"Virtualization Host <hostname>"}.
32490 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
32491 UNIX domain socket group ownership. This can be used to allow a
32492 'trusted' set of users access to management capabilities without
32495 Defaults to @samp{"root"}.
32499 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
32500 UNIX socket permissions for the R/O socket. This is used for monitoring
32503 Defaults to @samp{"0777"}.
32507 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
32508 UNIX socket permissions for the R/W socket. Default allows only root.
32509 If PolicyKit is enabled on the socket, the default will change to allow
32510 everyone (eg, 0777)
32512 Defaults to @samp{"0770"}.
32516 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
32517 UNIX socket permissions for the admin socket. Default allows only owner
32518 (root), do not change it unless you are sure to whom you are exposing
32521 Defaults to @samp{"0777"}.
32525 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
32526 The directory in which sockets will be found/created.
32528 Defaults to @samp{"/var/run/libvirt"}.
32532 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
32533 Authentication scheme for UNIX read-only sockets. By default socket
32534 permissions allow anyone to connect
32536 Defaults to @samp{"polkit"}.
32540 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
32541 Authentication scheme for UNIX read-write sockets. By default socket
32542 permissions only allow root. If PolicyKit support was compiled into
32543 libvirt, the default will be to use 'polkit' auth.
32545 Defaults to @samp{"polkit"}.
32549 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
32550 Authentication scheme for TCP sockets. If you don't enable SASL, then
32551 all TCP traffic is cleartext. Don't do this outside of a dev/test
32554 Defaults to @samp{"sasl"}.
32558 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
32559 Authentication scheme for TLS sockets. TLS sockets already have
32560 encryption provided by the TLS layer, and limited authentication is done
32563 It is possible to make use of any SASL authentication mechanism as well,
32564 by using 'sasl' for this option
32566 Defaults to @samp{"none"}.
32570 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
32571 API access control scheme.
32573 By default an authenticated user is allowed access to all APIs. Access
32574 drivers can place restrictions on this.
32576 Defaults to @samp{()}.
32580 @deftypevr {@code{libvirt-configuration} parameter} string key-file
32581 Server key file path. If set to an empty string, then no private key is
32584 Defaults to @samp{""}.
32588 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
32589 Server key file path. If set to an empty string, then no certificate is
32592 Defaults to @samp{""}.
32596 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
32597 Server key file path. If set to an empty string, then no CA certificate
32600 Defaults to @samp{""}.
32604 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
32605 Certificate revocation list path. If set to an empty string, then no
32608 Defaults to @samp{""}.
32612 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
32613 Disable verification of our own server certificates.
32615 When libvirtd starts it performs some sanity checks against its own
32618 Defaults to @samp{#f}.
32622 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
32623 Disable verification of client certificates.
32625 Client certificate verification is the primary authentication mechanism.
32626 Any client which does not present a certificate signed by the CA will be
32629 Defaults to @samp{#f}.
32633 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
32634 Whitelist of allowed x509 Distinguished Name.
32636 Defaults to @samp{()}.
32640 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
32641 Whitelist of allowed SASL usernames. The format for username depends on
32642 the SASL authentication mechanism.
32644 Defaults to @samp{()}.
32648 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
32649 Override the compile time default TLS priority string. The default is
32650 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
32651 is desired for libvirt to deviate from the global default settings.
32653 Defaults to @samp{"NORMAL"}.
32657 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
32658 Maximum number of concurrent client connections to allow over all
32661 Defaults to @samp{5000}.
32665 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
32666 Maximum length of queue of connections waiting to be accepted by the
32667 daemon. Note, that some protocols supporting retransmission may obey
32668 this so that a later reattempt at connection succeeds.
32670 Defaults to @samp{1000}.
32674 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
32675 Maximum length of queue of accepted but not yet authenticated clients.
32676 Set this to zero to turn this feature off
32678 Defaults to @samp{20}.
32682 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
32683 Number of workers to start up initially.
32685 Defaults to @samp{5}.
32689 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
32690 Maximum number of worker threads.
32692 If the number of active clients exceeds @code{min-workers}, then more
32693 threads are spawned, up to max_workers limit. Typically you'd want
32694 max_workers to equal maximum number of clients allowed.
32696 Defaults to @samp{20}.
32700 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
32701 Number of priority workers. If all workers from above pool are stuck,
32702 some calls marked as high priority (notably domainDestroy) can be
32703 executed in this pool.
32705 Defaults to @samp{5}.
32709 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
32710 Total global limit on concurrent RPC calls.
32712 Defaults to @samp{20}.
32716 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
32717 Limit on concurrent requests from a single client connection. To avoid
32718 one client monopolizing the server this should be a small fraction of
32719 the global max_requests and max_workers parameter.
32721 Defaults to @samp{5}.
32725 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
32726 Same as @code{min-workers} but for the admin interface.
32728 Defaults to @samp{1}.
32732 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
32733 Same as @code{max-workers} but for the admin interface.
32735 Defaults to @samp{5}.
32739 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
32740 Same as @code{max-clients} but for the admin interface.
32742 Defaults to @samp{5}.
32746 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
32747 Same as @code{max-queued-clients} but for the admin interface.
32749 Defaults to @samp{5}.
32753 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
32754 Same as @code{max-client-requests} but for the admin interface.
32756 Defaults to @samp{5}.
32760 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
32761 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32763 Defaults to @samp{3}.
32767 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
32770 A filter allows to select a different logging level for a given category
32771 of logs. The format for a filter is one of:
32782 where @code{name} is a string which is matched against the category
32783 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32784 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
32785 name in the filter can be a substring of the full category name, in
32786 order to match multiple similar categories), the optional @samp{"+"}
32787 prefix tells libvirt to log stack trace for each message matching name,
32788 and @code{x} is the minimal level where matching messages should be
32806 Multiple filters can be defined in a single filters statement, they just
32807 need to be separated by spaces.
32809 Defaults to @samp{"3:remote 4:event"}.
32813 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
32816 An output is one of the places to save logging information. The format
32817 for an output can be:
32821 output goes to stderr
32823 @item x:syslog:name
32824 use syslog for the output and use the given name as the ident
32826 @item x:file:file_path
32827 output to a file, with the given filepath
32830 output to journald logging system
32834 In all case the x prefix is the minimal level, acting as a filter
32851 Multiple outputs can be defined, they just need to be separated by
32854 Defaults to @samp{"3:stderr"}.
32858 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
32859 Allows usage of the auditing subsystem to be altered
32863 0: disable all auditing
32866 1: enable auditing, only if enabled on host
32869 2: enable auditing, and exit if disabled on host.
32873 Defaults to @samp{1}.
32877 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
32878 Send audit messages via libvirt logging infrastructure.
32880 Defaults to @samp{#f}.
32884 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
32885 Host UUID@. UUID must not have all digits be the same.
32887 Defaults to @samp{""}.
32891 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
32892 Source to read host UUID.
32896 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
32899 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
32903 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
32906 Defaults to @samp{"smbios"}.
32910 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
32911 A keepalive message is sent to a client after @code{keepalive_interval}
32912 seconds of inactivity to check if the client is still responding. If
32913 set to -1, libvirtd will never send keepalive requests; however clients
32914 can still send them and the daemon will send responses.
32916 Defaults to @samp{5}.
32920 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
32921 Maximum number of keepalive messages that are allowed to be sent to the
32922 client without getting any response before the connection is considered
32925 In other words, the connection is automatically closed approximately
32926 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
32927 the last message received from the client. When @code{keepalive-count}
32928 is set to 0, connections will be automatically closed after
32929 @code{keepalive-interval} seconds of inactivity without sending any
32930 keepalive messages.
32932 Defaults to @samp{5}.
32936 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
32937 Same as above but for admin interface.
32939 Defaults to @samp{5}.
32943 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
32944 Same as above but for admin interface.
32946 Defaults to @samp{5}.
32950 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
32951 Timeout for Open vSwitch calls.
32953 The @code{ovs-vsctl} utility is used for the configuration and its
32954 timeout option is set by default to 5 seconds to avoid potential
32955 infinite waits blocking libvirt.
32957 Defaults to @samp{5}.
32961 @c %end of autogenerated docs
32963 @subsubheading Virtlog daemon
32964 The virtlogd service is a server side daemon component of libvirt that is
32965 used to manage logs from virtual machine consoles.
32967 This daemon is not used directly by libvirt client applications, rather it
32968 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
32969 standalone daemon, the main @code{libvirtd} daemon can be restarted without
32970 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
32971 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
32973 @deffn {Scheme Variable} virtlog-service-type
32974 This is the type of the virtlog daemon.
32975 Its value must be a @code{virtlog-configuration}.
32978 (service virtlog-service-type
32979 (virtlog-configuration
32980 (max-clients 1000)))
32984 @deftypevar {@code{libvirt} parameter} package libvirt
32988 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
32989 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32991 Defaults to @samp{3}.
32995 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
32998 A filter allows to select a different logging level for a given category
32999 of logs The format for a filter is one of:
33010 where @code{name} is a string which is matched against the category
33011 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
33012 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
33013 be a substring of the full category name, in order to match multiple
33014 similar categories), the optional "+" prefix tells libvirt to log stack
33015 trace for each message matching name, and @code{x} is the minimal level
33016 where matching messages should be logged:
33033 Multiple filters can be defined in a single filters statement, they just
33034 need to be separated by spaces.
33036 Defaults to @samp{"3:remote 4:event"}.
33040 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
33043 An output is one of the places to save logging information The format
33044 for an output can be:
33048 output goes to stderr
33050 @item x:syslog:name
33051 use syslog for the output and use the given name as the ident
33053 @item x:file:file_path
33054 output to a file, with the given filepath
33057 output to journald logging system
33061 In all case the x prefix is the minimal level, acting as a filter
33078 Multiple outputs can be defined, they just need to be separated by
33081 Defaults to @samp{"3:stderr"}.
33085 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
33086 Maximum number of concurrent client connections to allow over all
33089 Defaults to @samp{1024}.
33093 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
33094 Maximum file size before rolling over.
33096 Defaults to @samp{2MB}
33100 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
33101 Maximum number of backup files to keep.
33103 Defaults to @samp{3}
33107 @anchor{transparent-emulation-qemu}
33108 @subsubheading Transparent Emulation with QEMU
33111 @cindex @code{binfmt_misc}
33112 @code{qemu-binfmt-service-type} provides support for transparent
33113 emulation of program binaries built for different architectures---e.g.,
33114 it allows you to transparently execute an ARMv7 program on an x86_64
33115 machine. It achieves this by combining the @uref{https://www.qemu.org,
33116 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
33117 This feature only allows you to emulate GNU/Linux on a different
33118 architecture, but see below for GNU/Hurd support.
33120 @defvr {Scheme Variable} qemu-binfmt-service-type
33121 This is the type of the QEMU/binfmt service for transparent emulation.
33122 Its value must be a @code{qemu-binfmt-configuration} object, which
33123 specifies the QEMU package to use as well as the architecture we want to
33127 (service qemu-binfmt-service-type
33128 (qemu-binfmt-configuration
33129 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
33132 In this example, we enable transparent emulation for the ARM and aarch64
33133 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
33134 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
33135 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
33138 @deftp {Data Type} qemu-binfmt-configuration
33139 This is the configuration for the @code{qemu-binfmt} service.
33142 @item @code{platforms} (default: @code{'()})
33143 The list of emulated QEMU platforms. Each item must be a @dfn{platform
33144 object} as returned by @code{lookup-qemu-platforms} (see below).
33146 For example, let's suppose you're on an x86_64 machine and you have this
33150 (service qemu-binfmt-service-type
33151 (qemu-binfmt-configuration
33152 (platforms (lookup-qemu-platforms "arm"))))
33158 guix build -s armhf-linux inkscape
33162 and it will build Inkscape for ARMv7 @emph{as if it were a native
33163 build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
33164 if you'd like to test a package build for an architecture you don't have
33167 @item @code{qemu} (default: @code{qemu})
33168 The QEMU package to use.
33172 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
33173 Return the list of QEMU platform objects corresponding to
33174 @var{platforms}@dots{}. @var{platforms} must be a list of strings
33175 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
33176 @code{"mips64el"}, and so on.
33179 @deffn {Scheme Procedure} qemu-platform? @var{obj}
33180 Return true if @var{obj} is a platform object.
33183 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
33184 Return the name of @var{platform}---a string such as @code{"arm"}.
33188 @subsubheading QEMU Guest Agent
33192 The QEMU guest agent provides control over the emulated system to the
33193 host. The @code{qemu-guest-agent} service runs the agent on Guix
33194 guests. To control the agent from the host, open a socket by invoking
33195 QEMU with the following arguments:
33198 qemu-system-x86_64 \
33199 -chardev socket,path=/tmp/qga.sock,server=on,wait=off,id=qga0 \
33200 -device virtio-serial \
33201 -device virtserialport,chardev=qga0,name=org.qemu.guest_agent.0 \
33205 This creates a socket at @file{/tmp/qga.sock} on the host. Once the
33206 guest agent is running, you can issue commands with @code{socat}:
33209 $ guix shell socat -- socat unix-connect:/tmp/qga.sock stdio
33210 @{"execute": "guest-get-host-name"@}
33211 @{"return": @{"host-name": "guix"@}@}
33214 See @url{https://wiki.qemu.org/Features/GuestAgent,QEMU guest agent
33215 documentation} for more options and commands.
33217 @defvr {Scheme Variable} qemu-guest-agent-service-type
33218 Service type for the QEMU guest agent service.
33221 @deftp {Data Type} qemu-guest-agent-configuration
33222 Configuration for the @code{qemu-guest-agent} service.
33225 @item @code{qemu} (default: @code{qemu-minimal})
33226 The QEMU package to use.
33228 @item @code{device} (default: @code{""})
33229 File name of the device or socket the agent uses to communicate with the
33230 host. If empty, QEMU uses a default file name.
33235 @subsubheading The Hurd in a Virtual Machine
33237 @cindex @code{hurd}
33241 Service @code{hurd-vm} provides support for running GNU/Hurd in a
33242 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
33243 to be used on GNU/Linux and the given GNU/Hurd operating system
33244 configuration is cross-compiled. The virtual machine is a Shepherd
33245 service that can be referred to by the names @code{hurd-vm} and
33246 @code{childhurd} and be controlled with commands such as:
33250 herd stop childhurd
33253 When the service is running, you can view its console by connecting to
33254 it with a VNC client, for example with:
33257 guix shell tigervnc-client -- vncviewer localhost:5900
33260 The default configuration (see @code{hurd-vm-configuration} below)
33261 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
33262 (the virtual machine emulator) redirects to port 10222 on the host.
33263 Thus, you can connect over SSH to the childhurd with:
33266 ssh root@@localhost -p 10022
33269 The childhurd is volatile and stateless: it starts with a fresh root
33270 file system every time you restart it. By default though, all the files
33271 under @file{/etc/childhurd} on the host are copied as is to the root
33272 file system of the childhurd when it boots. This allows you to
33273 initialize ``secrets'' inside the VM: SSH host keys, authorized
33274 substitute keys, and so on---see the explanation of @code{secret-root}
33277 @defvr {Scheme Variable} hurd-vm-service-type
33278 This is the type of the Hurd in a Virtual Machine service. Its value
33279 must be a @code{hurd-vm-configuration} object, which specifies the
33280 operating system (@pxref{operating-system Reference}) and the disk size
33281 for the Hurd Virtual Machine, the QEMU package to use as well as the
33282 options for running it.
33287 (service hurd-vm-service-type
33288 (hurd-vm-configuration
33289 (disk-size (* 5000 (expt 2 20))) ;5G
33290 (memory-size 1024))) ;1024MiB
33293 would create a disk image big enough to build GNU@tie{}Hello, with some
33297 @deftp {Data Type} hurd-vm-configuration
33298 The data type representing the configuration for
33299 @code{hurd-vm-service-type}.
33302 @item @code{os} (default: @var{%hurd-vm-operating-system})
33303 The operating system to instantiate. This default is bare-bones with a
33304 permissive OpenSSH secure shell daemon listening on port 2222
33305 (@pxref{Networking Services, @code{openssh-service-type}}).
33307 @item @code{qemu} (default: @code{qemu-minimal})
33308 The QEMU package to use.
33310 @item @code{image} (default: @var{hurd-vm-disk-image})
33311 The procedure used to build the disk-image built from this
33314 @item @code{disk-size} (default: @code{'guess})
33315 The size of the disk image.
33317 @item @code{memory-size} (default: @code{512})
33318 The memory size of the Virtual Machine in mebibytes.
33320 @item @code{options} (default: @code{'("--snapshot")})
33321 The extra options for running QEMU.
33323 @item @code{id} (default: @code{#f})
33324 If set, a non-zero positive integer used to parameterize Childhurd
33325 instances. It is appended to the service's name,
33326 e.g. @code{childhurd1}.
33328 @item @code{net-options} (default: @var{hurd-vm-net-options})
33329 The procedure used to produce the list of QEMU networking options.
33331 By default, it produces
33334 '("--device" "rtl8139,netdev=net0"
33335 "--netdev" (string-append
33337 "hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004,"
33338 "hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222,"
33339 "hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900"))
33342 with forwarded ports:
33345 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
33346 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
33347 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
33350 @item @code{secret-root} (default: @file{/etc/childhurd})
33351 The root directory with out-of-band secrets to be installed into the
33352 childhurd once it runs. Childhurds are volatile which means that on
33353 every startup, secrets such as the SSH host keys and Guix signing key
33356 If the @file{/etc/childhurd} directory does not exist, the
33357 @code{secret-service} running in the Childhurd will be sent an empty
33360 By default, the service automatically populates @file{/etc/childhurd}
33361 with the following non-volatile secrets, unless they already exist:
33364 /etc/childhurd/etc/guix/acl
33365 /etc/childhurd/etc/guix/signing-key.pub
33366 /etc/childhurd/etc/guix/signing-key.sec
33367 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
33368 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
33369 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
33370 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
33373 These files are automatically sent to the guest Hurd VM when it boots,
33374 including permissions.
33376 @cindex childhurd, offloading
33377 @cindex Hurd, offloading
33378 Having these files in place means that only a couple of things are
33379 missing to allow the host to offload @code{i586-gnu} builds to the
33384 Authorizing the childhurd's key on the host so that the host accepts
33385 build results coming from the childhurd, which can be done like so:
33388 guix archive --authorize < \
33389 /etc/childhurd/etc/guix/signing-key.pub
33393 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
33397 We're working towards making that happen automatically---get in touch
33398 with us at @email{guix-devel@@gnu.org} to discuss it!
33402 Note that by default the VM image is volatile, i.e., once stopped the
33403 contents are lost. If you want a stateful image instead, override the
33404 configuration's @code{image} and @code{options} without
33405 the @code{--snapshot} flag using something along these lines:
33408 (service hurd-vm-service-type
33409 (hurd-vm-configuration
33410 (image (const "/out/of/store/writable/hurd.img"))
33414 @subsubheading Ganeti
33419 This service is considered experimental. Configuration options may be changed
33420 in a backwards-incompatible manner, and not all features have been thorougly
33421 tested. Users of this service are encouraged to share their experience at
33422 @email{guix-devel@@gnu.org}.
33425 Ganeti is a virtual machine management system. It is designed to keep virtual
33426 machines running on a cluster of servers even in the event of hardware failures,
33427 and to make maintenance and recovery tasks easy. It consists of multiple
33428 services which are described later in this section. In addition to the Ganeti
33429 service, you will need the OpenSSH service (@pxref{Networking Services,
33430 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
33431 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
33432 and address (or use a DNS server).
33434 All nodes participating in a Ganeti cluster should have the same Ganeti and
33435 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
33436 cluster node that supports multiple storage backends, and installs the
33437 @code{debootstrap} and @code{guix} @dfn{OS providers}:
33440 (use-package-modules virtualization)
33441 (use-service-modules base ganeti networking ssh)
33444 (host-name "node1")
33445 (hosts-file (plain-file "hosts" (format #f "
33446 127.0.0.1 localhost
33449 192.168.1.200 ganeti.example.com
33450 192.168.1.201 node1.example.com node1
33451 192.168.1.202 node2.example.com node2
33454 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
33455 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
33456 (packages (append (map specification->package
33457 '("qemu" "lvm2" "drbd-utils" "ceph"
33458 ;; Add the debootstrap and guix OS providers.
33459 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
33462 (append (list (service static-networking-service-type
33463 (list (static-networking
33465 (list (network-address
33467 (value "192.168.1.201/24"))))
33469 (list (network-route
33470 (destination "default")
33471 (gateway "192.168.1.254"))))
33472 (name-servers '("192.168.1.252"
33473 "192.168.1.253")))))
33475 ;; Ganeti uses SSH to communicate between nodes.
33476 (service openssh-service-type
33477 (openssh-configuration
33478 (permit-root-login 'prohibit-password)))
33480 (service ganeti-service-type
33481 (ganeti-configuration
33482 ;; This list specifies allowed file system paths
33483 ;; for storing virtual machine images.
33484 (file-storage-paths '("/srv/ganeti/file-storage"))
33485 ;; This variable configures a single "variant" for
33486 ;; both Debootstrap and Guix that works with KVM.
33487 (os %default-ganeti-os))))
33491 Users are advised to read the
33492 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
33493 administrators guide} to learn about the various cluster options and
33494 day-to-day operations. There is also a
33495 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
33496 describing how to configure and initialize a small cluster.
33498 @defvr {Scheme Variable} ganeti-service-type
33499 This is a service type that includes all the various services that Ganeti
33502 Its value is a @code{ganeti-configuration} object that defines the package
33503 to use for CLI operations, as well as configuration for the various daemons.
33504 Allowed file storage paths and available guest operating systems are also
33505 configured through this data type.
33508 @deftp {Data Type} ganeti-configuration
33509 The @code{ganeti} service takes the following configuration options:
33512 @item @code{ganeti} (default: @code{ganeti})
33513 The @code{ganeti} package to use. It will be installed to the system profile
33514 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
33515 that the value specified here does not affect the other services as each refer
33516 to a specific @code{ganeti} package (see below).
33518 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
33519 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
33520 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
33521 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
33522 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
33523 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
33524 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
33525 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
33526 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
33527 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
33529 These options control the various daemons and cron jobs that are distributed
33530 with Ganeti. The possible values for these are described in detail below.
33531 To override a setting, you must use the configuration type for that service:
33534 (service ganeti-service-type
33535 (ganeti-configuration
33536 (rapi-configuration
33537 (ganeti-rapi-configuration
33538 (interface "eth1"))))
33539 (watcher-configuration
33540 (ganeti-watcher-configuration
33541 (rapi-ip "10.0.0.1"))))
33544 @item @code{file-storage-paths} (default: @code{'()})
33545 List of allowed directories for file storage backend.
33547 @item @code{os} (default: @code{%default-ganeti-os})
33548 List of @code{<ganeti-os>} records.
33551 In essence @code{ganeti-service-type} is shorthand for declaring each service
33555 (service ganeti-noded-service-type)
33556 (service ganeti-confd-service-type)
33557 (service ganeti-wconfd-service-type)
33558 (service ganeti-luxid-service-type)
33559 (service ganeti-kvmd-service-type)
33560 (service ganeti-mond-service-type)
33561 (service ganeti-metad-service-type)
33562 (service ganeti-watcher-service-type)
33563 (service ganeti-cleaner-service-type)
33566 Plus a service extension for @code{etc-service-type} that configures the file
33567 storage backend and OS variants.
33571 @deftp {Data Type} ganeti-os
33572 This data type is suitable for passing to the @code{os} parameter of
33573 @code{ganeti-configuration}. It takes the following parameters:
33577 The name for this OS provider. It is only used to specify where the
33578 configuration ends up. Setting it to ``debootstrap'' will create
33579 @file{/etc/ganeti/instance-debootstrap}.
33581 @item @code{extension}
33582 The file extension for variants of this OS type. For example
33583 @file{.conf} or @file{.scm}.
33585 @item @code{variants} (default: @code{'()})
33586 List of @code{ganeti-os-variant} objects for this OS.
33591 @deftp {Data Type} ganeti-os-variant
33592 This is the data type for a Ganeti OS variant. It takes the following
33597 The name of this variant.
33599 @item @code{configuration}
33600 A configuration file for this variant.
33604 @defvr {Scheme Variable} %default-debootstrap-hooks
33605 This variable contains hooks to configure networking and the GRUB bootloader.
33608 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
33609 This variable contains a list of packages suitable for a fully-virtualized guest.
33612 @deftp {Data Type} debootstrap-configuration
33614 This data type creates configuration files suitable for the debootstrap OS provider.
33617 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
33618 When not @code{#f}, this must be a G-expression that specifies a directory with
33619 scripts that will run when the OS is installed. It can also be a list of
33620 @code{(name . file-like)} pairs. For example:
33623 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
33626 That will create a directory with one executable named @code{99-hello-world}
33627 and run it every time this variant is installed. If set to @code{#f}, hooks
33628 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
33629 @item @code{proxy} (default: @code{#f})
33630 Optional HTTP proxy to use.
33631 @item @code{mirror} (default: @code{#f})
33632 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
33633 The default varies depending on the distribution.
33634 @item @code{arch} (default: @code{#f})
33635 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
33636 on an AArch64 host. Default is to use the current system architecture.
33637 @item @code{suite} (default: @code{"stable"})
33638 When set, this must be a Debian distribution ``suite'' such as @code{buster}
33639 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
33640 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
33641 List of extra packages that will get installed by dpkg in addition
33642 to the minimal system.
33643 @item @code{components} (default: @code{#f})
33644 When set, must be a list of Debian repository ``components''. For example
33645 @code{'("main" "contrib")}.
33646 @item @code{generate-cache?} (default: @code{#t})
33647 Whether to automatically cache the generated debootstrap archive.
33648 @item @code{clean-cache} (default: @code{14})
33649 Discard the cache after this amount of days. Use @code{#f} to never
33651 @item @code{partition-style} (default: @code{'msdos})
33652 The type of partition to create. When set, it must be one of
33653 @code{'msdos}, @code{'none} or a string.
33654 @item @code{partition-alignment} (default: @code{2048})
33655 Alignment of the partition in sectors.
33659 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
33660 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
33661 takes two parameters: a name and a @code{debootstrap-configuration} object.
33664 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
33665 This is a helper procedure that creates a @code{ganeti-os} record. It takes
33666 a list of variants created with @code{debootstrap-variant}.
33669 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
33670 This is a helper procedure that creates a @code{ganeti-os-variant} record for
33671 use with the Guix OS provider. It takes a name and a G-expression that returns
33672 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
33673 Guix System configuration.
33676 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
33677 This is a helper procedure that creates a @code{ganeti-os} record. It
33678 takes a list of variants produced by @code{guix-variant}.
33681 @defvr {Scheme Variable} %default-debootstrap-variants
33682 This is a convenience variable to make the debootstrap provider work
33683 ``out of the box'' without users having to declare variants manually. It
33684 contains a single debootstrap variant with the default configuration:
33687 (list (debootstrap-variant
33689 (debootstrap-configuration)))
33693 @defvr {Scheme Variable} %default-guix-variants
33694 This is a convenience variable to make the Guix OS provider work without
33695 additional configuration. It creates a virtual machine that has an SSH
33696 server, a serial console, and authorizes the Ganeti hosts SSH keys.
33699 (list (guix-variant
33701 (file-append ganeti-instance-guix
33702 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
33706 Users can implement support for OS providers unbeknownst to Guix by extending
33707 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
33713 (extension ".conf")
33715 (list (ganeti-os-variant
33717 (configuration (plain-file "bar" "this is fine"))))))
33720 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
33721 to a file in the store with contents @code{this is fine}. It also creates
33722 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
33724 Obviously this may not work for all OS providers out there. If you find the
33725 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
33727 The rest of this section documents the various services that are included by
33728 @code{ganeti-service-type}.
33730 @defvr {Scheme Variable} ganeti-noded-service-type
33731 @command{ganeti-noded} is the daemon responsible for node-specific functions
33732 within the Ganeti system. The value of this service must be a
33733 @code{ganeti-noded-configuration} object.
33736 @deftp {Data Type} ganeti-noded-configuration
33737 This is the configuration for the @code{ganeti-noded} service.
33740 @item @code{ganeti} (default: @code{ganeti})
33741 The @code{ganeti} package to use for this service.
33743 @item @code{port} (default: @code{1811})
33744 The TCP port on which the node daemon listens for network requests.
33746 @item @code{address} (default: @code{"0.0.0.0"})
33747 The network address that the daemon will bind to. The default address means
33748 bind to all available addresses.
33750 @item @code{interface} (default: @code{#f})
33751 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
33752 that the daemon will bind to.
33754 @item @code{max-clients} (default: @code{20})
33755 This sets a limit on the maximum number of simultaneous client connections
33756 that the daemon will handle. Connections above this count are accepted, but
33757 no responses will be sent until enough connections have closed.
33759 @item @code{ssl?} (default: @code{#t})
33760 Whether to use SSL/TLS to encrypt network communications. The certificate
33761 is automatically provisioned by the cluster and can be rotated with
33762 @command{gnt-cluster renew-crypto}.
33764 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33765 This can be used to provide a specific encryption key for TLS communications.
33767 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33768 This can be used to provide a specific certificate for TLS communications.
33770 @item @code{debug?} (default: @code{#f})
33771 When true, the daemon performs additional logging for debugging purposes.
33772 Note that this will leak encryption details to the log files, use with caution.
33777 @defvr {Scheme Variable} ganeti-confd-service-type
33778 @command{ganeti-confd} answers queries related to the configuration of a
33779 Ganeti cluster. The purpose of this daemon is to have a highly available
33780 and fast way to query cluster configuration values. It is automatically
33781 active on all @dfn{master candidates}. The value of this service must be a
33782 @code{ganeti-confd-configuration} object.
33786 @deftp {Data Type} ganeti-confd-configuration
33787 This is the configuration for the @code{ganeti-confd} service.
33790 @item @code{ganeti} (default: @code{ganeti})
33791 The @code{ganeti} package to use for this service.
33793 @item @code{port} (default: @code{1814})
33794 The UDP port on which to listen for network requests.
33796 @item @code{address} (default: @code{"0.0.0.0"})
33797 Network address that the daemon will bind to.
33799 @item @code{debug?} (default: @code{#f})
33800 When true, the daemon performs additional logging for debugging purposes.
33805 @defvr {Scheme Variable} ganeti-wconfd-service-type
33806 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
33807 about the cluster configuration and is the only entity that can accept
33808 changes to it. All jobs that need to modify the configuration will do so
33809 by sending appropriate requests to this daemon. It only runs on the
33810 @dfn{master node} and will automatically disable itself on other nodes.
33812 The value of this service must be a
33813 @code{ganeti-wconfd-configuration} object.
33816 @deftp {Data Type} ganeti-wconfd-configuration
33817 This is the configuration for the @code{ganeti-wconfd} service.
33820 @item @code{ganeti} (default: @code{ganeti})
33821 The @code{ganeti} package to use for this service.
33823 @item @code{no-voting?} (default: @code{#f})
33824 The daemon will refuse to start if the majority of cluster nodes does not
33825 agree that it is running on the master node. Set to @code{#t} to start
33826 even if a quorum can not be reached (dangerous, use with caution).
33828 @item @code{debug?} (default: @code{#f})
33829 When true, the daemon performs additional logging for debugging purposes.
33834 @defvr {Scheme Variable} ganeti-luxid-service-type
33835 @command{ganeti-luxid} is a daemon used to answer queries related to the
33836 configuration and the current live state of a Ganeti cluster. Additionally,
33837 it is the authoritative daemon for the Ganeti job queue. Jobs can be
33838 submitted via this daemon and it schedules and starts them.
33840 It takes a @code{ganeti-luxid-configuration} object.
33843 @deftp {Data Type} ganeti-luxid-configuration
33844 This is the configuration for the @code{ganeti-luxid} service.
33847 @item @code{ganeti} (default: @code{ganeti})
33848 The @code{ganeti} package to use for this service.
33850 @item @code{no-voting?} (default: @code{#f})
33851 The daemon will refuse to start if it cannot verify that the majority of
33852 cluster nodes believes that it is running on the master node. Set to
33853 @code{#t} to ignore such checks and start anyway (this can be dangerous).
33855 @item @code{debug?} (default: @code{#f})
33856 When true, the daemon performs additional logging for debugging purposes.
33861 @defvr {Scheme Variable} ganeti-rapi-service-type
33862 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
33863 the master node and can be used to perform cluster actions programmatically
33864 via a JSON-based RPC protocol.
33866 Most query operations are allowed without authentication (unless
33867 @var{require-authentication?} is set), whereas write operations require
33868 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
33869 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
33870 API documentation} for more information.
33872 The value of this service must be a @code{ganeti-rapi-configuration} object.
33875 @deftp {Data Type} ganeti-rapi-configuration
33876 This is the configuration for the @code{ganeti-rapi} service.
33879 @item @code{ganeti} (default: @code{ganeti})
33880 The @code{ganeti} package to use for this service.
33882 @item @code{require-authentication?} (default: @code{#f})
33883 Whether to require authentication even for read-only operations.
33885 @item @code{port} (default: @code{5080})
33886 The TCP port on which to listen to API requests.
33888 @item @code{address} (default: @code{"0.0.0.0"})
33889 The network address that the service will bind to. By default it listens
33890 on all configured addresses.
33892 @item @code{interface} (default: @code{#f})
33893 When set, it must specify a specific network interface such as @code{eth0}
33894 that the daemon will bind to.
33896 @item @code{max-clients} (default: @code{20})
33897 The maximum number of simultaneous client requests to handle. Further
33898 connections are allowed, but no responses are sent until enough connections
33901 @item @code{ssl?} (default: @code{#t})
33902 Whether to use SSL/TLS encryption on the RAPI port.
33904 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33905 This can be used to provide a specific encryption key for TLS communications.
33907 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33908 This can be used to provide a specific certificate for TLS communications.
33910 @item @code{debug?} (default: @code{#f})
33911 When true, the daemon performs additional logging for debugging purposes.
33912 Note that this will leak encryption details to the log files, use with caution.
33917 @defvr {Scheme Variable} ganeti-kvmd-service-type
33918 @command{ganeti-kvmd} is responsible for determining whether a given KVM
33919 instance was shut down by an administrator or a user. Normally Ganeti will
33920 restart an instance that was not stopped through Ganeti itself. If the
33921 cluster option @code{user_shutdown} is true, this daemon monitors the
33922 @code{QMP} socket provided by QEMU and listens for shutdown events, and
33923 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
33924 it shuts down gracefully by itself.
33926 It takes a @code{ganeti-kvmd-configuration} object.
33929 @deftp {Data Type} ganeti-kvmd-configuration
33932 @item @code{ganeti} (default: @code{ganeti})
33933 The @code{ganeti} package to use for this service.
33935 @item @code{debug?} (default: @code{#f})
33936 When true, the daemon performs additional logging for debugging purposes.
33941 @defvr {Scheme Variable} ganeti-mond-service-type
33942 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
33943 functionality. It is responsible for running data collectors and publish the
33944 collected information through a HTTP interface.
33946 It takes a @code{ganeti-mond-configuration} object.
33949 @deftp {Data Type} ganeti-mond-configuration
33952 @item @code{ganeti} (default: @code{ganeti})
33953 The @code{ganeti} package to use for this service.
33955 @item @code{port} (default: @code{1815})
33956 The port on which the daemon will listen.
33958 @item @code{address} (default: @code{"0.0.0.0"})
33959 The network address that the daemon will bind to. By default it binds to all
33960 available interfaces.
33962 @item @code{debug?} (default: @code{#f})
33963 When true, the daemon performs additional logging for debugging purposes.
33968 @defvr {Scheme Variable} ganeti-metad-service-type
33969 @command{ganeti-metad} is an optional daemon that can be used to provide
33970 information about the cluster to instances or OS install scripts.
33972 It takes a @code{ganeti-metad-configuration} object.
33975 @deftp {Data Type} ganeti-metad-configuration
33978 @item @code{ganeti} (default: @code{ganeti})
33979 The @code{ganeti} package to use for this service.
33981 @item @code{port} (default: @code{80})
33982 The port on which the daemon will listen.
33984 @item @code{address} (default: @code{#f})
33985 If set, the daemon will bind to this address only. If left unset, the behavior
33986 depends on the cluster configuration.
33988 @item @code{debug?} (default: @code{#f})
33989 When true, the daemon performs additional logging for debugging purposes.
33994 @defvr {Scheme Variable} ganeti-watcher-service-type
33995 @command{ganeti-watcher} is a script designed to run periodically and ensure
33996 the health of a cluster. It will automatically restart instances that have
33997 stopped without Ganeti's consent, and repairs DRBD links in case a node has
33998 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
33999 that are not running. If the cluster parameter @code{ensure_node_health}
34000 is set, the watcher will also shutdown instances and DRBD devices if the
34001 node it is running on is declared offline by known master candidates.
34003 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
34005 The service takes a @code{ganeti-watcher-configuration} object.
34008 @deftp {Data Type} ganeti-watcher-configuration
34011 @item @code{ganeti} (default: @code{ganeti})
34012 The @code{ganeti} package to use for this service.
34014 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
34015 How often to run the script. The default is every five minutes.
34017 @item @code{rapi-ip} (default: @code{#f})
34018 This option needs to be specified only if the RAPI daemon is configured to use
34019 a particular interface or address. By default the cluster address is used.
34021 @item @code{job-age} (default: @code{(* 6 3600)})
34022 Archive cluster jobs older than this age, specified in seconds. The default
34023 is 6 hours. This keeps @command{gnt-job list} manageable.
34025 @item @code{verify-disks?} (default: @code{#t})
34026 If this is @code{#f}, the watcher will not try to repair broken DRBD links
34027 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
34030 @item @code{debug?} (default: @code{#f})
34031 When @code{#t}, the script performs additional logging for debugging purposes.
34036 @defvr {Scheme Variable} ganeti-cleaner-service-type
34037 @command{ganeti-cleaner} is a script designed to run periodically and remove
34038 old files from the cluster. This service type controls two @dfn{cron jobs}:
34039 one intended for the master node that permanently purges old cluster jobs,
34040 and one intended for every node that removes expired X509 certificates, keys,
34041 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
34042 it is safe to include even on non-master nodes as it will disable itself as
34045 It takes a @code{ganeti-cleaner-configuration} object.
34048 @deftp {Data Type} ganeti-cleaner-configuration
34051 @item @code{ganeti} (default: @code{ganeti})
34052 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
34054 @item @code{master-schedule} (default: @code{"45 1 * * *"})
34055 How often to run the master cleaning job. The default is once per day, at
34058 @item @code{node-schedule} (default: @code{"45 2 * * *"})
34059 How often to run the node cleaning job. The default is once per day, at
34065 @node Version Control Services
34066 @subsection Version Control Services
34068 The @code{(gnu services version-control)} module provides a service to
34069 allow remote access to local Git repositories. There are three options:
34070 the @code{git-daemon-service}, which provides access to repositories via
34071 the @code{git://} unsecured TCP-based protocol, extending the
34072 @code{nginx} web server to proxy some requests to
34073 @code{git-http-backend}, or providing a web interface with
34074 @code{cgit-service-type}.
34076 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
34078 Return a service that runs @command{git daemon}, a simple TCP server to
34079 expose repositories over the Git protocol for anonymous access.
34081 The optional @var{config} argument should be a
34082 @code{<git-daemon-configuration>} object, by default it allows read-only
34083 access to exported@footnote{By creating the magic file
34084 @file{git-daemon-export-ok} in the repository directory.} repositories under
34089 @deftp {Data Type} git-daemon-configuration
34090 Data type representing the configuration for @code{git-daemon-service}.
34093 @item @code{package} (default: @code{git})
34094 Package object of the Git distributed version control system.
34096 @item @code{export-all?} (default: @code{#f})
34097 Whether to allow access for all Git repositories, even if they do not
34098 have the @file{git-daemon-export-ok} file.
34100 @item @code{base-path} (default: @file{/srv/git})
34101 Whether to remap all the path requests as relative to the given path.
34102 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
34103 @samp{example.com}, then if you later try to pull
34104 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
34105 path as @file{/srv/git/hello.git}.
34107 @item @code{user-path} (default: @code{#f})
34108 Whether to allow @code{~user} notation to be used in requests. When
34109 specified with empty string, requests to
34110 @indicateurl{git://host/~alice/foo} is taken as a request to access
34111 @code{foo} repository in the home directory of user @code{alice}. If
34112 @code{(user-path "@var{path}")} is specified, the same request is taken
34113 as a request to access @file{@var{path}/foo} repository in the home
34114 directory of user @code{alice}.
34116 @item @code{listen} (default: @code{'()})
34117 Whether to listen on specific IP addresses or hostnames, defaults to
34120 @item @code{port} (default: @code{#f})
34121 Whether to listen on an alternative port, which defaults to 9418.
34123 @item @code{whitelist} (default: @code{'()})
34124 If not empty, only allow access to this list of directories.
34126 @item @code{extra-options} (default: @code{'()})
34127 Extra options will be passed to @command{git daemon}, please run
34128 @command{man git-daemon} for more information.
34133 The @code{git://} protocol lacks authentication. When you pull from a
34134 repository fetched via @code{git://}, you don't know whether the data you
34135 receive was modified or is even coming from the specified host, and your
34136 connection is subject to eavesdropping. It's better to use an authenticated
34137 and encrypted transport, such as @code{https}. Although Git allows you
34138 to serve repositories using unsophisticated file-based web servers,
34139 there is a faster protocol implemented by the @code{git-http-backend}
34140 program. This program is the back-end of a proper Git web service. It
34141 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
34142 on running the necessary @code{fcgiwrap} daemon.
34144 Guix has a separate configuration data type for serving Git repositories
34147 @deftp {Data Type} git-http-configuration
34148 Data type representing the configuration for a future
34149 @code{git-http-service-type}; can currently be used to configure Nginx
34150 through @code{git-http-nginx-location-configuration}.
34153 @item @code{package} (default: @var{git})
34154 Package object of the Git distributed version control system.
34156 @item @code{git-root} (default: @file{/srv/git})
34157 Directory containing the Git repositories to expose to the world.
34159 @item @code{export-all?} (default: @code{#f})
34160 Whether to expose access for all Git repositories in @var{git-root},
34161 even if they do not have the @file{git-daemon-export-ok} file.
34163 @item @code{uri-path} (default: @samp{/git/})
34164 Path prefix for Git access. With the default @samp{/git/} prefix, this
34165 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
34166 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
34167 with this prefix are not passed on to this Git instance.
34169 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
34170 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
34175 There is no @code{git-http-service-type}, currently; instead you can
34176 create an @code{nginx-location-configuration} from a
34177 @code{git-http-configuration} and then add that location to a web
34180 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
34181 [config=(git-http-configuration)]
34182 Compute an @code{nginx-location-configuration} that corresponds to the
34183 given Git http configuration. An example nginx service definition to
34184 serve the default @file{/srv/git} over HTTPS might be:
34187 (service nginx-service-type
34188 (nginx-configuration
34191 (nginx-server-configuration
34192 (listen '("443 ssl"))
34193 (server-name "git.my-host.org")
34195 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
34196 (ssl-certificate-key
34197 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
34200 (git-http-nginx-location-configuration
34201 (git-http-configuration (uri-path "/"))))))))))
34204 This example assumes that you are using Let's Encrypt to get your TLS
34205 certificate. @xref{Certificate Services}. The default @code{certbot}
34206 service will redirect all HTTP traffic on @code{git.my-host.org} to
34207 HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
34208 system services. @xref{Web Services}.
34211 @subsubheading Cgit Service
34213 @cindex Cgit service
34214 @cindex Git, web interface
34215 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
34216 repositories written in C.
34218 The following example will configure the service with default values.
34219 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
34222 (service cgit-service-type)
34225 The @code{file-object} type designates either a file-like object
34226 (@pxref{G-Expressions, file-like objects}) or a string.
34228 @c %start of fragment
34230 Available @code{cgit-configuration} fields are:
34232 @deftypevr {@code{cgit-configuration} parameter} package package
34237 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
34238 NGINX configuration.
34242 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
34243 Specifies a command which will be invoked to format the content of about
34244 pages (both top-level and for each repository).
34246 Defaults to @samp{""}.
34250 @deftypevr {@code{cgit-configuration} parameter} string agefile
34251 Specifies a path, relative to each repository path, which can be used to
34252 specify the date and time of the youngest commit in the repository.
34254 Defaults to @samp{""}.
34258 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
34259 Specifies a command that will be invoked for authenticating repository
34262 Defaults to @samp{""}.
34266 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
34267 Flag which, when set to @samp{age}, enables date ordering in the branch
34268 ref list, and when set @samp{name} enables ordering by branch name.
34270 Defaults to @samp{"name"}.
34274 @deftypevr {@code{cgit-configuration} parameter} string cache-root
34275 Path used to store the cgit cache entries.
34277 Defaults to @samp{"/var/cache/cgit"}.
34281 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
34282 Number which specifies the time-to-live, in minutes, for the cached
34283 version of repository pages accessed with a fixed SHA1.
34285 Defaults to @samp{-1}.
34289 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
34290 Number which specifies the time-to-live, in minutes, for the cached
34291 version of repository pages accessed without a fixed SHA1.
34293 Defaults to @samp{5}.
34297 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
34298 Number which specifies the time-to-live, in minutes, for the cached
34299 version of the repository summary page.
34301 Defaults to @samp{5}.
34305 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
34306 Number which specifies the time-to-live, in minutes, for the cached
34307 version of the repository index page.
34309 Defaults to @samp{5}.
34313 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
34314 Number which specifies the time-to-live, in minutes, for the result of
34315 scanning a path for Git repositories.
34317 Defaults to @samp{15}.
34321 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
34322 Number which specifies the time-to-live, in minutes, for the cached
34323 version of the repository about page.
34325 Defaults to @samp{15}.
34329 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
34330 Number which specifies the time-to-live, in minutes, for the cached
34331 version of snapshots.
34333 Defaults to @samp{5}.
34337 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
34338 The maximum number of entries in the cgit cache. When set to @samp{0},
34339 caching is disabled.
34341 Defaults to @samp{0}.
34345 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
34346 Sort items in the repo list case sensitively.
34348 Defaults to @samp{#t}.
34352 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
34353 List of common prefixes which, when combined with a repository URL,
34354 generates valid clone URLs for the repository.
34356 Defaults to @samp{()}.
34360 @deftypevr {@code{cgit-configuration} parameter} list clone-url
34361 List of @code{clone-url} templates.
34363 Defaults to @samp{()}.
34367 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
34368 Command which will be invoked to format commit messages.
34370 Defaults to @samp{""}.
34374 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
34375 Flag which, when set to @samp{date}, enables strict date ordering in the
34376 commit log, and when set to @samp{topo} enables strict topological
34379 Defaults to @samp{"git log"}.
34383 @deftypevr {@code{cgit-configuration} parameter} file-object css
34384 URL which specifies the css document to include in all cgit pages.
34386 Defaults to @samp{"/share/cgit/cgit.css"}.
34390 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
34391 Specifies a command which will be invoked to format names and email
34392 address of committers, authors, and taggers, as represented in various
34393 places throughout the cgit interface.
34395 Defaults to @samp{""}.
34399 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
34400 Flag which, when set to @samp{#t}, will make cgit generate a HTML
34401 fragment suitable for embedding in other HTML pages.
34403 Defaults to @samp{#f}.
34407 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
34408 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
34409 commit history graph to the left of the commit messages in the
34410 repository log page.
34412 Defaults to @samp{#f}.
34416 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
34417 Flag which, when set to @samp{#t}, allows all filter settings to be
34418 overridden in repository-specific cgitrc files.
34420 Defaults to @samp{#f}.
34424 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
34425 Flag which, when set to @samp{#t}, allows users to follow a file in the
34428 Defaults to @samp{#f}.
34432 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
34433 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
34436 Defaults to @samp{#t}.
34440 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
34441 Flag which, when set to @samp{#t}, will make cgit generate extra links
34442 "summary", "commit", "tree" for each repo in the repository index.
34444 Defaults to @samp{#f}.
34448 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
34449 Flag which, when set to @samp{#t}, will make cgit display the owner of
34450 each repo in the repository index.
34452 Defaults to @samp{#t}.
34456 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
34457 Flag which, when set to @samp{#t}, will make cgit print the number of
34458 modified files for each commit on the repository log page.
34460 Defaults to @samp{#f}.
34464 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
34465 Flag which, when set to @samp{#t}, will make cgit print the number of
34466 added and removed lines for each commit on the repository log page.
34468 Defaults to @samp{#f}.
34472 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
34473 Flag which, when set to @code{#t}, will make cgit display remote
34474 branches in the summary and refs views.
34476 Defaults to @samp{#f}.
34480 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
34481 Flag which, when set to @code{1}, will make cgit use the subject of the
34482 parent commit as link text when generating links to parent commits in
34485 Defaults to @samp{#f}.
34489 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
34490 Flag which, when set to @samp{#t}, will make cgit use the subject of the
34491 parent commit as link text when generating links to parent commits in
34494 Defaults to @samp{#f}.
34498 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
34499 Flag which, when set to @samp{#t}, will make cgit generate linenumber
34500 links for plaintext blobs printed in the tree view.
34502 Defaults to @samp{#t}.
34506 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
34507 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
34508 set any repo specific settings.
34510 Defaults to @samp{#f}.
34514 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
34515 URL used as link to a shortcut icon for cgit.
34517 Defaults to @samp{"/favicon.ico"}.
34521 @deftypevr {@code{cgit-configuration} parameter} string footer
34522 The content of the file specified with this option will be included
34523 verbatim at the bottom of all pages (i.e.@: it replaces the standard
34524 "generated by..."@: message).
34526 Defaults to @samp{""}.
34530 @deftypevr {@code{cgit-configuration} parameter} string head-include
34531 The content of the file specified with this option will be included
34532 verbatim in the HTML HEAD section on all pages.
34534 Defaults to @samp{""}.
34538 @deftypevr {@code{cgit-configuration} parameter} string header
34539 The content of the file specified with this option will be included
34540 verbatim at the top of all pages.
34542 Defaults to @samp{""}.
34546 @deftypevr {@code{cgit-configuration} parameter} file-object include
34547 Name of a configfile to include before the rest of the current config-
34550 Defaults to @samp{""}.
34554 @deftypevr {@code{cgit-configuration} parameter} string index-header
34555 The content of the file specified with this option will be included
34556 verbatim above the repository index.
34558 Defaults to @samp{""}.
34562 @deftypevr {@code{cgit-configuration} parameter} string index-info
34563 The content of the file specified with this option will be included
34564 verbatim below the heading on the repository index page.
34566 Defaults to @samp{""}.
34570 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
34571 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
34572 in the servers timezone.
34574 Defaults to @samp{#f}.
34578 @deftypevr {@code{cgit-configuration} parameter} file-object logo
34579 URL which specifies the source of an image which will be used as a logo
34582 Defaults to @samp{"/share/cgit/cgit.png"}.
34586 @deftypevr {@code{cgit-configuration} parameter} string logo-link
34587 URL loaded when clicking on the cgit logo image.
34589 Defaults to @samp{""}.
34593 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
34594 Command which will be invoked to format the Owner column of the main
34597 Defaults to @samp{""}.
34601 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
34602 Number of items to display in atom feeds view.
34604 Defaults to @samp{10}.
34608 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
34609 Number of entries to list per page in "log" view.
34611 Defaults to @samp{50}.
34615 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
34616 Number of commit message characters to display in "log" view.
34618 Defaults to @samp{80}.
34622 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
34623 Specifies the number of entries to list per page on the repository index
34626 Defaults to @samp{50}.
34630 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
34631 Specifies the maximum number of repo description characters to display
34632 on the repository index page.
34634 Defaults to @samp{80}.
34638 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
34639 Specifies the maximum size of a blob to display HTML for in KBytes.
34641 Defaults to @samp{0}.
34645 @deftypevr {@code{cgit-configuration} parameter} string max-stats
34646 Maximum statistics period. Valid values are @samp{week},@samp{month},
34647 @samp{quarter} and @samp{year}.
34649 Defaults to @samp{""}.
34653 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
34654 Mimetype for the specified filename extension.
34656 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
34657 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
34658 "image/png") (svg "image/svg+xml"))}.
34662 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
34663 Specifies the file to use for automatic mimetype lookup.
34665 Defaults to @samp{""}.
34669 @deftypevr {@code{cgit-configuration} parameter} string module-link
34670 Text which will be used as the formatstring for a hyperlink when a
34671 submodule is printed in a directory listing.
34673 Defaults to @samp{""}.
34677 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
34678 If set to the value @samp{#t} caching will be disabled.
34680 Defaults to @samp{#f}.
34684 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
34685 If set to @samp{#t} showing full author email addresses will be
34688 Defaults to @samp{#f}.
34692 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
34693 Flag which, when set to @samp{#t}, will make cgit omit the standard
34694 header on all pages.
34696 Defaults to @samp{#f}.
34700 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
34701 A list of subdirectories inside of @code{repository-directory}, relative
34702 to it, that should loaded as Git repositories. An empty list means that
34703 all subdirectories will be loaded.
34705 Defaults to @samp{()}.
34709 @deftypevr {@code{cgit-configuration} parameter} file-object readme
34710 Text which will be used as default value for @code{cgit-repo-readme}.
34712 Defaults to @samp{""}.
34716 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
34717 If set to @code{#t} and @code{repository-directory} is enabled, if any
34718 repositories are found with a suffix of @code{.git}, this suffix will be
34719 removed for the URL and name.
34721 Defaults to @samp{#f}.
34725 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
34726 Maximum number of files to consider when detecting renames.
34728 Defaults to @samp{-1}.
34732 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
34733 The way in which repositories in each section are sorted.
34735 Defaults to @samp{""}.
34739 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
34740 Text used as content for the @code{robots} meta-tag.
34742 Defaults to @samp{("noindex" "nofollow")}.
34746 @deftypevr {@code{cgit-configuration} parameter} string root-desc
34747 Text printed below the heading on the repository index page.
34749 Defaults to @samp{"a fast webinterface for the git dscm"}.
34753 @deftypevr {@code{cgit-configuration} parameter} string root-readme
34754 The content of the file specified with this option will be included
34755 verbatim below the ``about'' link on the repository index page.
34757 Defaults to @samp{""}.
34761 @deftypevr {@code{cgit-configuration} parameter} string root-title
34762 Text printed as heading on the repository index page.
34764 Defaults to @samp{""}.
34768 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
34769 If set to @samp{#t} and repository-directory is enabled,
34770 repository-directory will recurse into directories whose name starts
34771 with a period. Otherwise, repository-directory will stay away from such
34772 directories, considered as ``hidden''. Note that this does not apply to
34773 the @file{.git} directory in non-bare repos.
34775 Defaults to @samp{#f}.
34779 @deftypevr {@code{cgit-configuration} parameter} list snapshots
34780 Text which specifies the default set of snapshot formats that cgit
34781 generates links for.
34783 Defaults to @samp{()}.
34787 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
34788 Name of the directory to scan for repositories (represents
34791 Defaults to @samp{"/srv/git"}.
34795 @deftypevr {@code{cgit-configuration} parameter} string section
34796 The name of the current repository section - all repositories defined
34797 after this option will inherit the current section name.
34799 Defaults to @samp{""}.
34803 @deftypevr {@code{cgit-configuration} parameter} string section-sort
34804 Flag which, when set to @samp{1}, will sort the sections on the
34805 repository listing by name.
34807 Defaults to @samp{""}.
34811 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
34812 A number which, if defined prior to repository-directory, specifies how
34813 many path elements from each repo path to use as a default section name.
34815 Defaults to @samp{0}.
34819 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
34820 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
34823 Defaults to @samp{#f}.
34827 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
34828 Specifies a command which will be invoked to format plaintext blobs in
34831 Defaults to @samp{""}.
34835 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
34836 Specifies the number of branches to display in the repository ``summary''
34839 Defaults to @samp{10}.
34843 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
34844 Specifies the number of log entries to display in the repository
34847 Defaults to @samp{10}.
34851 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
34852 Specifies the number of tags to display in the repository ``summary''
34855 Defaults to @samp{10}.
34859 @deftypevr {@code{cgit-configuration} parameter} string strict-export
34860 Filename which, if specified, needs to be present within the repository
34861 for cgit to allow access to that repository.
34863 Defaults to @samp{""}.
34867 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
34868 URL which, if specified, will be used as root for all cgit links.
34870 Defaults to @samp{"/"}.
34874 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
34875 A list of @dfn{cgit-repo} records to use with config.
34877 Defaults to @samp{()}.
34879 Available @code{repository-cgit-configuration} fields are:
34881 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
34882 A mask of snapshot formats for this repo that cgit generates links for,
34883 restricted by the global @code{snapshots} setting.
34885 Defaults to @samp{()}.
34889 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
34890 Override the default @code{source-filter}.
34892 Defaults to @samp{""}.
34896 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
34897 The relative URL used to access the repository.
34899 Defaults to @samp{""}.
34903 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
34904 Override the default @code{about-filter}.
34906 Defaults to @samp{""}.
34910 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
34911 Flag which, when set to @samp{age}, enables date ordering in the branch
34912 ref list, and when set to @samp{name} enables ordering by branch name.
34914 Defaults to @samp{""}.
34918 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
34919 A list of URLs which can be used to clone repo.
34921 Defaults to @samp{()}.
34925 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
34926 Override the default @code{commit-filter}.
34928 Defaults to @samp{""}.
34932 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
34933 Flag which, when set to @samp{date}, enables strict date ordering in the
34934 commit log, and when set to @samp{topo} enables strict topological
34937 Defaults to @samp{""}.
34941 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
34942 The name of the default branch for this repository. If no such branch
34943 exists in the repository, the first branch name (when sorted) is used as
34944 default instead. By default branch pointed to by HEAD, or ``master'' if
34945 there is no suitable HEAD.
34947 Defaults to @samp{""}.
34951 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
34952 The value to show as repository description.
34954 Defaults to @samp{""}.
34958 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
34959 The value to show as repository homepage.
34961 Defaults to @samp{""}.
34965 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
34966 Override the default @code{email-filter}.
34968 Defaults to @samp{""}.
34972 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
34973 A flag which can be used to disable the global setting
34974 @code{enable-commit-graph?}.
34976 Defaults to @samp{disabled}.
34980 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
34981 A flag which can be used to disable the global setting
34982 @code{enable-log-filecount?}.
34984 Defaults to @samp{disabled}.
34988 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
34989 A flag which can be used to disable the global setting
34990 @code{enable-log-linecount?}.
34992 Defaults to @samp{disabled}.
34996 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
34997 Flag which, when set to @code{#t}, will make cgit display remote
34998 branches in the summary and refs views.
35000 Defaults to @samp{disabled}.
35004 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
35005 A flag which can be used to override the global setting
35006 @code{enable-subject-links?}.
35008 Defaults to @samp{disabled}.
35012 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
35013 A flag which can be used to override the global setting
35014 @code{enable-html-serving?}.
35016 Defaults to @samp{disabled}.
35020 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
35021 Flag which, when set to @code{#t}, hides the repository from the
35024 Defaults to @samp{#f}.
35028 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
35029 Flag which, when set to @samp{#t}, ignores the repository.
35031 Defaults to @samp{#f}.
35035 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
35036 URL which specifies the source of an image which will be used as a logo
35037 on this repo’s pages.
35039 Defaults to @samp{""}.
35043 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
35044 URL loaded when clicking on the cgit logo image.
35046 Defaults to @samp{""}.
35050 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
35051 Override the default @code{owner-filter}.
35053 Defaults to @samp{""}.
35057 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
35058 Text which will be used as the formatstring for a hyperlink when a
35059 submodule is printed in a directory listing. The arguments for the
35060 formatstring are the path and SHA1 of the submodule commit.
35062 Defaults to @samp{""}.
35066 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
35067 Text which will be used as the formatstring for a hyperlink when a
35068 submodule with the specified subdirectory path is printed in a directory
35071 Defaults to @samp{()}.
35075 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
35076 Override the default maximum statistics period.
35078 Defaults to @samp{""}.
35082 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
35083 The value to show as repository name.
35085 Defaults to @samp{""}.
35089 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
35090 A value used to identify the owner of the repository.
35092 Defaults to @samp{""}.
35096 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
35097 An absolute path to the repository directory.
35099 Defaults to @samp{""}.
35103 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
35104 A path (relative to repo) which specifies a file to include verbatim as
35105 the ``About'' page for this repo.
35107 Defaults to @samp{""}.
35111 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
35112 The name of the current repository section - all repositories defined
35113 after this option will inherit the current section name.
35115 Defaults to @samp{""}.
35119 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
35120 Extra options will be appended to cgitrc file.
35122 Defaults to @samp{()}.
35128 @deftypevr {@code{cgit-configuration} parameter} list extra-options
35129 Extra options will be appended to cgitrc file.
35131 Defaults to @samp{()}.
35136 @c %end of fragment
35138 However, it could be that you just want to get a @code{cgitrc} up and
35139 running. In that case, you can pass an @code{opaque-cgit-configuration}
35140 as a record to @code{cgit-service-type}. As its name indicates, an
35141 opaque configuration does not have easy reflective capabilities.
35143 Available @code{opaque-cgit-configuration} fields are:
35145 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
35149 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
35150 The contents of the @code{cgitrc}, as a string.
35153 For example, if your @code{cgitrc} is just the empty string, you
35154 could instantiate a cgit service like this:
35157 (service cgit-service-type
35158 (opaque-cgit-configuration
35162 @subsubheading Gitolite Service
35164 @cindex Gitolite service
35165 @cindex Git, hosting
35166 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
35167 repositories on a central server.
35169 Gitolite can handle multiple repositories and users, and supports flexible
35170 configuration of the permissions for the users on the repositories.
35172 The following example will configure Gitolite using the default @code{git}
35173 user, and the provided SSH public key.
35176 (service gitolite-service-type
35177 (gitolite-configuration
35178 (admin-pubkey (plain-file
35180 "ssh-rsa AAAA... guix@@example.com"))))
35183 Gitolite is configured through a special admin repository which you can clone,
35184 for example, if you setup Gitolite on @code{example.com}, you would run the
35185 following command to clone the admin repository.
35188 git clone git@@example.com:gitolite-admin
35191 When the Gitolite service is activated, the provided @code{admin-pubkey} will
35192 be inserted in to the @file{keydir} directory in the gitolite-admin
35193 repository. If this results in a change in the repository, it will be
35194 committed using the message ``gitolite setup by GNU Guix''.
35196 @deftp {Data Type} gitolite-configuration
35197 Data type representing the configuration for @code{gitolite-service-type}.
35200 @item @code{package} (default: @var{gitolite})
35201 Gitolite package to use.
35203 @item @code{user} (default: @var{git})
35204 User to use for Gitolite. This will be user that you use when accessing
35207 @item @code{group} (default: @var{git})
35208 Group to use for Gitolite.
35210 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
35211 Directory in which to store the Gitolite configuration and repositories.
35213 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
35214 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
35215 representing the configuration for Gitolite.
35217 @item @code{admin-pubkey} (default: @var{#f})
35218 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
35219 setup Gitolite. This will be inserted in to the @file{keydir} directory
35220 within the gitolite-admin repository.
35222 To specify the SSH key as a string, use the @code{plain-file} function.
35225 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
35231 @deftp {Data Type} gitolite-rc-file
35232 Data type representing the Gitolite RC file.
35235 @item @code{umask} (default: @code{#o0077})
35236 This controls the permissions Gitolite sets on the repositories and their
35239 A value like @code{#o0027} will give read access to the group used by Gitolite
35240 (by default: @code{git}). This is necessary when using Gitolite with software
35241 like cgit or gitweb.
35243 @item @code{unsafe-pattern} (default: @code{#f})
35244 An optional Perl regular expression for catching unsafe configurations in
35245 the configuration file. See
35246 @uref{https://gitolite.com/gitolite/git-config.html#compensating-for-unsafe_patt,
35247 Gitolite's documentation} for more information.
35249 When the value is not @code{#f}, it should be a string containing a Perl
35250 regular expression, such as @samp{"[`~#\$\&()|;<>]"}, which is the default
35251 value used by gitolite. It rejects any special character in configuration
35252 that might be interpreted by a shell, which is useful when sharing the
35253 administration burden with other people that do not otherwise have shell
35254 access on the server.
35256 @item @code{git-config-keys} (default: @code{""})
35257 Gitolite allows you to set git config values using the @samp{config}
35258 keyword. This setting allows control over the config keys to accept.
35260 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
35261 Set the role names allowed to be used by users running the perms command.
35263 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
35264 This setting controls the commands and features to enable within Gitolite.
35270 @subsubheading Gitile Service
35272 @cindex Gitile service
35274 @uref{https://git.lepiller.eu/gitile, Gitile} is a Git forge for viewing
35275 public git repository contents from a web browser.
35277 Gitile works best in collaboration with Gitolite, and will serve the public
35278 repositories from Gitolite by default. The service should listen only on
35279 a local port, and a webserver should be configured to serve static resources.
35280 The gitile service provides an easy way to extend the Nginx service for
35281 that purpose (@pxref{NGINX}).
35283 The following example will configure Gitile to serve repositories from a
35284 custom location, with some default messages for the home page and the
35288 (service gitile-service-type
35289 (gitile-configuration
35290 (repositories "/srv/git")
35291 (base-git-url "https://myweb.site/git")
35292 (index-title "My git repositories")
35293 (intro '((p "This is all my public work!")))
35294 (footer '((p "This is the end")))
35295 (nginx-server-block
35296 (nginx-server-configuration
35298 "/etc/letsencrypt/live/myweb.site/fullchain.pem")
35299 (ssl-certificate-key
35300 "/etc/letsencrypt/live/myweb.site/privkey.pem")
35301 (listen '("443 ssl http2" "[::]:443 ssl http2"))
35304 ;; Allow for https anonymous fetch on /git/ urls.
35305 (git-http-nginx-location-configuration
35306 (git-http-configuration
35308 (git-root "/var/lib/gitolite/repositories")))))))))
35311 In addition to the configuration record, you should configure your git
35312 repositories to contain some optional information. First, your public
35313 repositories need to contain the @file{git-daemon-export-ok} magic file
35314 that allows Git to export the repository. Gitile uses the presence of this
35315 file to detect public repositories it should make accessible. To do so with
35316 Gitolite for instance, modify your @file{conf/gitolite.conf} to include
35317 this in the repositories you want to make public:
35324 In addition, Gitile can read the repository configuration to display more
35325 information on the repository. Gitile uses the gitweb namespace for its
35326 configuration. As an example, you can use the following in your
35327 @file{conf/gitolite.conf}:
35332 desc = A long description, optionally with <i>HTML</i>, shown on the index page
35333 config gitweb.name = The Foo Project
35334 config gitweb.synopsis = A short description, shown on the main page of the project
35337 Do not forget to commit and push these changes once you are satisfied. You
35338 may need to change your gitolite configuration to allow the previous
35339 configuration options to be set. One way to do that is to add the
35340 following service definition:
35343 (service gitolite-service-type
35344 (gitolite-configuration
35345 (admin-pubkey (local-file "key.pub"))
35349 ;; Allow to set any configuration key
35350 (git-config-keys ".*")
35351 ;; Allow any text as a valid configuration value
35352 (unsafe-patt "^$")))))
35355 @deftp {Data Type} gitile-configuration
35356 Data type representing the configuration for @code{gitile-service-type}.
35359 @item @code{package} (default: @var{gitile})
35360 Gitile package to use.
35362 @item @code{host} (default: @code{"localhost"})
35363 The host on which gitile is listening.
35365 @item @code{port} (default: @code{8080})
35366 The port on which gitile is listening.
35368 @item @code{database} (default: @code{"/var/lib/gitile/gitile-db.sql"})
35369 The location of the database.
35371 @item @code{repositories} (default: @code{"/var/lib/gitolite/repositories"})
35372 The location of the repositories. Note that only public repositories will
35373 be shown by Gitile. To make a repository public, add an empty
35374 @file{git-daemon-export-ok} file at the root of that repository.
35376 @item @code{base-git-url}
35377 The base git url that will be used to show clone commands.
35379 @item @code{index-title} (default: @code{"Index"})
35380 The page title for the index page that lists all the available repositories.
35382 @item @code{intro} (default: @code{'()})
35383 The intro content, as a list of sxml expressions. This is shown above the list
35384 of repositories, on the index page.
35386 @item @code{footer} (default: @code{'()})
35387 The footer content, as a list of sxml expressions. This is shown on every
35388 page served by Gitile.
35390 @item @code{nginx-server-block}
35391 An nginx server block that will be extended and used as a reverse proxy by
35392 Gitile to serve its pages, and as a normal web server to serve its assets.
35394 You can use this block to add more custom URLs to your domain, such as a
35395 @code{/git/} URL for anonymous clones, or serving any other files you would
35401 @node Game Services
35402 @subsection Game Services
35404 @subsubheading The Battle for Wesnoth Service
35406 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
35407 based tactical strategy game, with several single player campaigns, and
35408 multiplayer games (both networked and local).
35410 @defvar {Scheme Variable} wesnothd-service-type
35411 Service type for the wesnothd service. Its value must be a
35412 @code{wesnothd-configuration} object. To run wesnothd in the default
35413 configuration, instantiate it as:
35416 (service wesnothd-service-type)
35420 @deftp {Data Type} wesnothd-configuration
35421 Data type representing the configuration of @command{wesnothd}.
35424 @item @code{package} (default: @code{wesnoth-server})
35425 The wesnoth server package to use.
35427 @item @code{port} (default: @code{15000})
35428 The port to bind the server to.
35433 @node PAM Mount Service
35434 @subsection PAM Mount Service
35437 The @code{(gnu services pam-mount)} module provides a service allowing
35438 users to mount volumes when they log in. It should be able to mount any
35439 volume format supported by the system.
35441 @defvar {Scheme Variable} pam-mount-service-type
35442 Service type for PAM Mount support.
35445 @deftp {Data Type} pam-mount-configuration
35446 Data type representing the configuration of PAM Mount.
35448 It takes the following parameters:
35452 The configuration rules that will be used to generate
35453 @file{/etc/security/pam_mount.conf.xml}.
35455 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
35456 Guile Reference Manual}), and the default ones don't mount anything for
35460 `((debug (@@ (enable "0")))
35461 (mntoptions (@@ (allow ,(string-join
35462 '("nosuid" "nodev" "loop"
35463 "encryption" "fsck" "nonempty"
35464 "allow_root" "allow_other")
35466 (mntoptions (@@ (require "nosuid,nodev")))
35467 (logout (@@ (wait "0")
35471 (mkmountpoint (@@ (enable "1")
35475 Some @code{volume} elements must be added to automatically mount volumes
35476 at login. Here's an example allowing the user @code{alice} to mount her
35477 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
35478 the partition where he stores his data:
35481 (define pam-mount-rules
35482 `((debug (@@ (enable "0")))
35483 (volume (@@ (user "alice")
35486 (mountpoint "/home/alice")))
35487 (volume (@@ (user "bob")
35490 (mountpoint "/home/bob/data")
35491 (options "defaults,autodefrag,compress")))
35492 (mntoptions (@@ (allow ,(string-join
35493 '("nosuid" "nodev" "loop"
35494 "encryption" "fsck" "nonempty"
35495 "allow_root" "allow_other")
35497 (mntoptions (@@ (require "nosuid,nodev")))
35498 (logout (@@ (wait "0")
35502 (mkmountpoint (@@ (enable "1")
35503 (remove "true")))))
35505 (service pam-mount-service-type
35506 (pam-mount-configuration
35507 (rules pam-mount-rules)))
35510 The complete list of possible options can be found in the man page for
35511 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
35516 @node Guix Services
35517 @subsection Guix Services
35519 @subsubheading Guix Build Coordinator
35520 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
35521 Coordinator} aids in distributing derivation builds among machines
35522 running an @dfn{agent}. The build daemon is still used to build the
35523 derivations, but the Guix Build Coordinator manages allocating builds
35524 and working with the results.
35526 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
35527 more connected @dfn{agent} processes. The coordinator process handles
35528 clients submitting builds, and allocating builds to agents. The agent
35529 processes talk to a build daemon to actually perform the builds, then
35530 send the results back to the coordinator.
35532 There is a script to run the coordinator component of the Guix Build
35533 Coordinator, but the Guix service uses a custom Guile script instead, to
35534 provide better integration with G-expressions used in the configuration.
35536 @defvar {Scheme Variable} guix-build-coordinator-service-type
35537 Service type for the Guix Build Coordinator. Its value must be a
35538 @code{guix-build-coordinator-configuration} object.
35541 @deftp {Data Type} guix-build-coordinator-configuration
35542 Data type representing the configuration of the Guix Build Coordinator.
35545 @item @code{package} (default: @code{guix-build-coordinator})
35546 The Guix Build Coordinator package to use.
35548 @item @code{user} (default: @code{"guix-build-coordinator"})
35549 The system user to run the service as.
35551 @item @code{group} (default: @code{"guix-build-coordinator"})
35552 The system group to run the service as.
35554 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
35555 The URI to use for the database.
35557 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
35558 The URI describing how to listen to requests from agent processes.
35560 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
35561 The URI describing how to listen to requests from clients. The client
35562 API allows submitting builds and currently isn't authenticated, so take
35563 care when configuring this value.
35565 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
35566 A G-expression for the allocation strategy to be used. This is a
35567 procedure that takes the datastore as an argument and populates the
35568 allocation plan in the database.
35570 @item @code{hooks} (default: @var{'()})
35571 An association list of hooks. These provide a way to execute arbitrary
35572 code upon certain events, like a build result being processed.
35574 @item @code{parallel-hooks} (default: @var{'()})
35575 Hooks can be configured to run in parallel. This parameter is an
35576 association list of hooks to do in parallel, where the key is the symbol
35577 for the hook and the value is the number of threads to run.
35579 @item @code{guile} (default: @code{guile-3.0-latest})
35580 The Guile package with which to run the Guix Build Coordinator.
35585 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
35586 Service type for a Guix Build Coordinator agent. Its value must be a
35587 @code{guix-build-coordinator-agent-configuration} object.
35590 @deftp {Data Type} guix-build-coordinator-agent-configuration
35591 Data type representing the configuration a Guix Build Coordinator agent.
35594 @item @code{package} (default: @code{guix-build-coordinator/agent-only})
35595 The Guix Build Coordinator package to use.
35597 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
35598 The system user to run the service as.
35600 @item @code{coordinator} (default: @code{"http://localhost:8745"})
35601 The URI to use when connecting to the coordinator.
35603 @item @code{authentication}
35604 Record describing how this agent should authenticate with the
35605 coordinator. Possible record types are described below.
35607 @item @code{systems} (default: @code{#f})
35608 The systems for which this agent should fetch builds. The agent process
35609 will use the current system it's running on as the default.
35611 @item @code{max-parallel-builds} (default: @code{1})
35612 The number of builds to perform in parallel.
35614 @item @code{max-1min-load-average} (default: @code{#f})
35615 Load average value to look at when considering starting new builds, if
35616 the 1 minute load average exceeds this value, the agent will wait before
35617 starting new builds.
35619 This will be unspecified if the value is @code{#f}, and the agent will
35620 use the number of cores reported by the system as the max 1 minute load
35623 @item @code{derivation-substitute-urls} (default: @code{#f})
35624 URLs from which to attempt to fetch substitutes for derivations, if the
35625 derivations aren't already available.
35627 @item @code{non-derivation-substitute-urls} (default: @code{#f})
35628 URLs from which to attempt to fetch substitutes for build inputs, if the
35629 input store items aren't already available.
35634 @deftp {Data Type} guix-build-coordinator-agent-password-auth
35635 Data type representing an agent authenticating with a coordinator via a
35640 The UUID of the agent. This should be generated by the coordinator
35641 process, stored in the coordinator database, and used by the intended
35644 @item @code{password}
35645 The password to use when connecting to the coordinator.
35650 @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
35651 Data type representing an agent authenticating with a coordinator via a
35652 UUID and password read from a file.
35656 The UUID of the agent. This should be generated by the coordinator
35657 process, stored in the coordinator database, and used by the intended
35660 @item @code{password-file}
35661 A file containing the password to use when connecting to the
35667 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
35668 Data type representing an agent authenticating with a coordinator via a
35669 dynamic auth token and agent name.
35672 @item @code{agent-name}
35673 Name of an agent, this is used to match up to an existing entry in the
35674 database if there is one. When no existing entry is found, a new entry
35675 is automatically added.
35678 Dynamic auth token, this is created and stored in the coordinator
35679 database, and is used by the agent to authenticate.
35684 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
35685 Data type representing an agent authenticating with a coordinator via a
35686 dynamic auth token read from a file and agent name.
35689 @item @code{agent-name}
35690 Name of an agent, this is used to match up to an existing entry in the
35691 database if there is one. When no existing entry is found, a new entry
35692 is automatically added.
35694 @item @code{token-file}
35695 File containing the dynamic auth token, this is created and stored in
35696 the coordinator database, and is used by the agent to authenticate.
35701 The Guix Build Coordinator package contains a script to query an
35702 instance of the Guix Data Service for derivations to build, and then
35703 submit builds for those derivations to the coordinator. The service
35704 type below assists in running this script. This is an additional tool
35705 that may be useful when building derivations contained within an
35706 instance of the Guix Data Service.
35708 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
35709 Service type for the
35710 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
35711 value must be a @code{guix-build-coordinator-queue-builds-configuration}
35715 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
35716 Data type representing the options to the queue builds from guix data
35720 @item @code{package} (default: @code{guix-build-coordinator})
35721 The Guix Build Coordinator package to use.
35723 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
35724 The system user to run the service as.
35726 @item @code{coordinator} (default: @code{"http://localhost:8746"})
35727 The URI to use when connecting to the coordinator.
35729 @item @code{systems} (default: @code{#f})
35730 The systems for which to fetch derivations to build.
35732 @item @code{systems-and-targets} (default: @code{#f})
35733 An association list of system and target pairs for which to fetch
35734 derivations to build.
35736 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
35737 The Guix Data Service instance from which to query to find out about
35738 derivations to build.
35740 @item @code{guix-data-service-build-server-id} (default: @code{#f})
35741 The Guix Data Service build server ID corresponding to the builds being
35742 submitted. Providing this speeds up the submitting of builds as
35743 derivations that have already been submitted can be skipped before
35744 asking the coordinator to build them.
35746 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
35747 A file to record which commits have been processed, to avoid needlessly
35748 processing them again if the service is restarted.
35753 @subsubheading Guix Data Service
35754 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
35755 and provides data about GNU Guix. This includes information about
35756 packages, derivations and lint warnings.
35758 The data is stored in a PostgreSQL database, and available through a web
35761 @defvar {Scheme Variable} guix-data-service-type
35762 Service type for the Guix Data Service. Its value must be a
35763 @code{guix-data-service-configuration} object. The service optionally
35764 extends the getmail service, as the guix-commits mailing list is used to
35765 find out about changes in the Guix git repository.
35768 @deftp {Data Type} guix-data-service-configuration
35769 Data type representing the configuration of the Guix Data Service.
35772 @item @code{package} (default: @code{guix-data-service})
35773 The Guix Data Service package to use.
35775 @item @code{user} (default: @code{"guix-data-service"})
35776 The system user to run the service as.
35778 @item @code{group} (default: @code{"guix-data-service"})
35779 The system group to run the service as.
35781 @item @code{port} (default: @code{8765})
35782 The port to bind the web service to.
35784 @item @code{host} (default: @code{"127.0.0.1"})
35785 The host to bind the web service to.
35787 @item @code{getmail-idle-mailboxes} (default: @code{#f})
35788 If set, this is the list of mailboxes that the getmail service will be
35789 configured to listen to.
35791 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
35792 If set, this is the @code{getmail-retriever-configuration} object with
35793 which to configure getmail to fetch mail from the guix-commits mailing
35796 @item @code{extra-options} (default: @var{'()})
35797 Extra command line options for @code{guix-data-service}.
35799 @item @code{extra-process-jobs-options} (default: @var{'()})
35800 Extra command line options for @code{guix-data-service-process-jobs}.
35805 @subsubheading Nar Herder
35806 The @uref{https://git.cbaines.net/guix/nar-herder/about/,Nar Herder} is
35807 a utility for managing a collection of nars.
35809 @defvar {Scheme Variable} nar-herder-type
35810 Service type for the Guix Data Service. Its value must be a
35811 @code{nar-herder-configuration} object. The service optionally
35812 extends the getmail service, as the guix-commits mailing list is used to
35813 find out about changes in the Guix git repository.
35816 @deftp {Data Type} nar-herder-configuration
35817 Data type representing the configuration of the Guix Data Service.
35820 @item @code{package} (default: @code{nar-herder})
35821 The Nar Herder package to use.
35823 @item @code{user} (default: @code{"nar-herder"})
35824 The system user to run the service as.
35826 @item @code{group} (default: @code{"nar-herder"})
35827 The system group to run the service as.
35829 @item @code{port} (default: @code{8734})
35830 The port to bind the server to.
35832 @item @code{host} (default: @code{"127.0.0.1"})
35833 The host to bind the server to.
35835 @item @code{mirror} (default: @code{#f})
35836 Optional URL of the other Nar Herder instance which should be mirrored.
35837 This means that this Nar Herder instance will download it's database,
35838 and keep it up to date.
35840 @item @code{database} (default: @code{"/var/lib/nar-herder/nar_herder.db"})
35841 Location for the database. If this Nar Herder instance is mirroring
35842 another, the database will be downloaded if it doesn't exist. If this
35843 Nar Herder instance isn't mirroring another, an empty database will be
35846 @item @code{database-dump} (default: @code{"/var/lib/nar-herder/nar_herder_dump.db"})
35847 Location of the database dump. This is created and regularly updated by
35848 taking a copy of the database. This is the version of the database that
35849 is available to download.
35851 @item @code{storage} (default: @code{#f})
35852 Optional location in which to store nars.
35854 @item @code{storage-limit} (default: @code{"none"})
35855 Limit in bytes for the nars stored in the storage location. This can
35856 also be set to ``none'' so that there is no limit.
35858 When the storage location exceeds this size, nars are removed according
35859 to the nar removal criteria.
35861 @item @code{storage-nar-removal-criteria} (default: @code{'()})
35862 Criteria used to remove nars from the storage location. These are used
35863 in conjunction with the storage limit.
35865 When the storage location exceeds the storage limit size, nars will be
35866 checked against the nar removal criteria and if any of the criteria
35867 match, they will be removed. This will continue until the storage
35868 location is below the storage limit size.
35870 Each criteria is specified by a string, then an equals sign, then
35871 another string. Currently, only one criteria is supported, checking if a
35872 nar is stored on another Nar Herder instance.
35874 @item @code{ttl} (default: @code{#f})
35875 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
35876 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
35877 days, @code{1m} means 1 month, and so on.
35879 This allows the user's Guix to keep substitute information in cache for
35882 @item @code{negative-ttl} (default: @code{#f})
35883 Similarly produce @code{Cache-Control} HTTP headers to advertise the
35884 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
35885 which the HTTP 404 code is returned. By default, no negative TTL is
35888 @item @code{log-level} (default: @code{'DEBUG})
35889 Log level to use, specify a log level like @code{'INFO} to stop logging
35890 individual requests.
35895 @node Linux Services
35896 @subsection Linux Services
35899 @cindex out of memory killer
35901 @cindex early out of memory daemon
35902 @subsubheading Early OOM Service
35904 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
35905 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
35906 space and provides a more responsive and configurable alternative to the
35907 in-kernel OOM killer. It is useful to prevent the system from becoming
35908 unresponsive when it runs out of memory.
35910 @deffn {Scheme Variable} earlyoom-service-type
35911 The service type for running @command{earlyoom}, the Early OOM daemon.
35912 Its value must be a @code{earlyoom-configuration} object, described
35913 below. The service can be instantiated in its default configuration
35917 (service earlyoom-service-type)
35921 @deftp {Data Type} earlyoom-configuration
35922 This is the configuration record for the @code{earlyoom-service-type}.
35925 @item @code{earlyoom} (default: @var{earlyoom})
35926 The Earlyoom package to use.
35928 @item @code{minimum-available-memory} (default: @code{10})
35929 The threshold for the minimum @emph{available} memory, in percentages.
35931 @item @code{minimum-free-swap} (default: @code{10})
35932 The threshold for the minimum free swap memory, in percentages.
35934 @item @code{prefer-regexp} (default: @code{#f})
35935 A regular expression (as a string) to match the names of the processes
35936 that should be preferably killed.
35938 @item @code{avoid-regexp} (default: @code{#f})
35939 A regular expression (as a string) to match the names of the processes
35940 that should @emph{not} be killed.
35942 @item @code{memory-report-interval} (default: @code{0})
35943 The interval in seconds at which a memory report is printed. It is
35944 disabled by default.
35946 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
35947 A boolean indicating whether the positive adjustments set in
35948 @file{/proc/*/oom_score_adj} should be ignored.
35950 @item @code{show-debug-messages?} (default: @code{#f})
35951 A boolean indicating whether debug messages should be printed. The logs
35952 are saved at @file{/var/log/earlyoom.log}.
35954 @item @code{send-notification-command} (default: @code{#f})
35955 This can be used to provide a custom command used for sending
35961 @cindex kernel module loader
35962 @subsubheading Kernel Module Loader Service
35964 The kernel module loader service allows one to load loadable kernel
35965 modules at boot. This is especially useful for modules that don't
35966 autoload and need to be manually loaded, as is the case with
35969 @deffn {Scheme Variable} kernel-module-loader-service-type
35970 The service type for loading loadable kernel modules at boot with
35971 @command{modprobe}. Its value must be a list of strings representing
35972 module names. For example loading the drivers provided by
35973 @code{ddcci-driver-linux}, in debugging mode by passing some module
35974 parameters, can be done as follow:
35977 (use-modules (gnu) (gnu services))
35978 (use-package-modules linux)
35979 (use-service-modules linux)
35981 (define ddcci-config
35982 (plain-file "ddcci.conf"
35983 "options ddcci dyndbg delay=120"))
35987 (services (cons* (service kernel-module-loader-service-type
35988 '("ddcci" "ddcci_backlight"))
35989 (simple-service 'ddcci-config etc-service-type
35990 (list `("modprobe.d/ddcci.conf"
35993 (kernel-loadable-modules (list ddcci-driver-linux)))
35998 @cindex Platform Reliability, Availability and Serviceability daemon
35999 @subsubheading Rasdaemon Service
36001 The Rasdaemon service provides a daemon which monitors platform
36002 @acronym{RAS, Reliability@comma{} Availability@comma{} and Serviceability} reports from
36003 Linux kernel trace events, logging them to syslogd.
36005 Reliability, Availability and Serviceability is a concept used on servers meant
36006 to measure their robustness.
36008 @strong{Relability} is the probability that a system will produce correct
36012 @item Generally measured as Mean Time Between Failures (MTBF), and
36013 @item Enhanced by features that help to avoid, detect and repair hardware
36017 @strong{Availability} is the probability that a system is operational at a
36021 @item Generally measured as a percentage of downtime per a period of time, and
36022 @item Often uses mechanisms to detect and correct hardware faults in runtime.
36025 @strong{Serviceability} is the simplicity and speed with which a system can be
36026 repaired or maintained:
36029 @item Generally measured on Mean Time Between Repair (MTBR).
36033 Among the monitoring measures, the most usual ones include:
36036 @item CPU – detect errors at instruction execution and at L1/L2/L3 caches;
36037 @item Memory – add error correction logic (ECC) to detect and correct errors;
36038 @item I/O – add CRC checksums for transferred data;
36039 @item Storage – RAID, journal file systems, checksums, Self-Monitoring,
36040 Analysis and Reporting Technology (SMART).
36043 By monitoring the number of occurrences of error detections, it is possible to
36044 identify if the probability of hardware errors is increasing, and, on such
36045 case, do a preventive maintenance to replace a degraded component while those
36046 errors are correctable.
36048 For detailed information about the types of error events gathered and how to
36049 make sense of them, see the kernel administrator's guide at
36050 @url{https://www.kernel.org/doc/html/latest/admin-guide/ras.html}.
36052 @defvr {Scheme Variable} rasdaemon-service-type
36053 Service type for the @command{rasdaemon} service. It accepts a
36054 @code{rasdaemon-configuration} object. Instantiating like
36057 (service rasdaemon-service-type)
36060 will load with a default configuration, which monitors all events and logs to
36064 @deftp {Data Type} rasdaemon-configuration
36065 The data type representing the configuration of @command{rasdaemon}.
36068 @item @code{record?} (default: @code{#f})
36070 A boolean indicating whether to record the events in an SQLite database. This
36071 provides a more structured access to the information contained in the log file.
36072 The database location is hard-coded to @file{/var/lib/rasdaemon/ras-mc_event.db}.
36078 @cindex compressed swap
36079 @cindex Compressed RAM-based block devices
36080 @subsubheading Zram Device Service
36082 The Zram device service provides a compressed swap device in system
36083 memory. The Linux Kernel documentation has more information about
36084 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
36087 @deffn {Scheme Variable} zram-device-service-type
36088 This service creates the zram block device, formats it as swap and
36089 enables it as a swap device. The service's value is a
36090 @code{zram-device-configuration} record.
36092 @deftp {Data Type} zram-device-configuration
36093 This is the data type representing the configuration for the zram-device
36097 @item @code{size} (default @code{"1G"})
36098 This is the amount of space you wish to provide for the zram device. It
36099 accepts a string and can be a number of bytes or use a suffix, eg.:
36100 @code{"512M"} or @code{1024000}.
36101 @item @code{compression-algorithm} (default @code{'lzo})
36102 This is the compression algorithm you wish to use. It is difficult to
36103 list all the possible compression options, but common ones supported by
36104 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
36105 @item @code{memory-limit} (default @code{0})
36106 This is the maximum amount of memory which the zram device can use.
36107 Setting it to '0' disables the limit. While it is generally expected
36108 that compression will be 2:1, it is possible that uncompressable data
36109 can be written to swap and this is a method to limit how much memory can
36110 be used. It accepts a string and can be a number of bytes or use a
36111 suffix, eg.: @code{"2G"}.
36112 @item @code{priority} (default @code{#f})
36113 This is the priority of the swap device created from the zram device.
36114 @xref{Swap Space} for a description of swap priorities. You might want
36115 to set a specific priority for the zram device, otherwise it could end
36116 up not being used much for the reasons described there.
36122 @node Hurd Services
36123 @subsection Hurd Services
36125 @defvr {Scheme Variable} hurd-console-service-type
36126 This service starts the fancy @code{VGA} console client on the Hurd.
36128 The service's value is a @code{hurd-console-configuration} record.
36131 @deftp {Data Type} hurd-console-configuration
36132 This is the data type representing the configuration for the
36133 hurd-console-service.
36136 @item @code{hurd} (default: @var{hurd})
36137 The Hurd package to use.
36141 @defvr {Scheme Variable} hurd-getty-service-type
36142 This service starts a tty using the Hurd @code{getty} program.
36144 The service's value is a @code{hurd-getty-configuration} record.
36147 @deftp {Data Type} hurd-getty-configuration
36148 This is the data type representing the configuration for the
36149 hurd-getty-service.
36152 @item @code{hurd} (default: @var{hurd})
36153 The Hurd package to use.
36156 The name of the console this Getty runs on---e.g., @code{"tty1"}.
36158 @item @code{baud-rate} (default: @code{38400})
36159 An integer specifying the baud rate of the tty.
36164 @node Miscellaneous Services
36165 @subsection Miscellaneous Services
36167 @cindex fingerprint
36168 @subsubheading Fingerprint Service
36170 The @code{(gnu services authentication)} module provides a DBus service to
36171 read and identify fingerprints via a fingerprint sensor.
36173 @defvr {Scheme Variable} fprintd-service-type
36174 The service type for @command{fprintd}, which provides the fingerprint
36175 reading capability.
36178 (service fprintd-service-type)
36183 @subsubheading System Control Service
36185 The @code{(gnu services sysctl)} provides a service to configure kernel
36186 parameters at boot.
36188 @defvr {Scheme Variable} sysctl-service-type
36189 The service type for @command{sysctl}, which modifies kernel parameters
36190 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
36194 (service sysctl-service-type
36195 (sysctl-configuration
36196 (settings '(("net.ipv4.ip_forward" . "1")))))
36199 Since @code{sysctl-service-type} is used in the default lists of
36200 services, @code{%base-services} and @code{%desktop-services}, you can
36201 use @code{modify-services} to change its configuration and add the
36202 kernel parameters that you want (@pxref{Service Reference,
36203 @code{modify-services}}).
36206 (modify-services %base-services
36207 (sysctl-service-type config =>
36208 (sysctl-configuration
36209 (settings (append '(("net.ipv4.ip_forward" . "1"))
36210 %default-sysctl-settings)))))
36215 @deftp {Data Type} sysctl-configuration
36216 The data type representing the configuration of @command{sysctl}.
36219 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
36220 The @command{sysctl} executable to use.
36222 @item @code{settings} (default: @code{%default-sysctl-settings})
36223 An association list specifies kernel parameters and their values.
36227 @defvr {Scheme Variable} %default-sysctl-settings
36228 An association list specifying the default @command{sysctl} parameters
36233 @subsubheading PC/SC Smart Card Daemon Service
36235 The @code{(gnu services security-token)} module provides the following service
36236 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
36237 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
36238 manager that coordinates communications with smart card readers, smart cards
36239 and cryptographic tokens that are connected to the system.
36241 @defvr {Scheme Variable} pcscd-service-type
36242 Service type for the @command{pcscd} service. Its value must be a
36243 @code{pcscd-configuration} object. To run pcscd in the default
36244 configuration, instantiate it as:
36247 (service pcscd-service-type)
36251 @deftp {Data Type} pcscd-configuration
36252 The data type representing the configuration of @command{pcscd}.
36255 @item @code{pcsc-lite} (default: @code{pcsc-lite})
36256 The pcsc-lite package that provides pcscd.
36257 @item @code{usb-drivers} (default: @code{(list ccid)})
36258 List of packages that provide USB drivers to pcscd. Drivers are expected to be
36259 under @file{pcsc/drivers} in the store directory of the package.
36264 @subsubheading Lirc Service
36266 The @code{(gnu services lirc)} module provides the following service.
36268 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
36269 [#:device #f] [#:driver #f] [#:config-file #f] @
36270 [#:extra-options '()]
36271 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
36272 decodes infrared signals from remote controls.
36274 Optionally, @var{device}, @var{driver} and @var{config-file}
36275 (configuration file name) may be specified. See @command{lircd} manual
36278 Finally, @var{extra-options} is a list of additional command-line options
36279 passed to @command{lircd}.
36283 @subsubheading Spice Service
36285 The @code{(gnu services spice)} module provides the following service.
36287 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
36288 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
36289 that enables sharing the clipboard with a vm and setting the guest display
36290 resolution when the graphical console window resizes.
36293 @cindex inputattach
36294 @subsubheading inputattach Service
36296 @cindex tablet input, for Xorg
36297 @cindex touchscreen input, for Xorg
36298 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
36299 use input devices such as Wacom tablets, touchscreens, or joysticks with the
36300 Xorg display server.
36302 @deffn {Scheme Variable} inputattach-service-type
36303 Type of a service that runs @command{inputattach} on a device and
36304 dispatches events from it.
36307 @deftp {Data Type} inputattach-configuration
36309 @item @code{device-type} (default: @code{"wacom"})
36310 The type of device to connect to. Run @command{inputattach --help}, from the
36311 @code{inputattach} package, to see the list of supported device types.
36313 @item @code{device} (default: @code{"/dev/ttyS0"})
36314 The device file to connect to the device.
36316 @item @code{baud-rate} (default: @code{#f})
36317 Baud rate to use for the serial connection.
36318 Should be a number or @code{#f}.
36320 @item @code{log-file} (default: @code{#f})
36321 If true, this must be the name of a file to log messages to.
36325 @subsubheading Dictionary Service
36327 The @code{(gnu services dict)} module provides the following service:
36329 @defvr {Scheme Variable} dicod-service-type
36330 This is the type of the service that runs the @command{dicod} daemon, an
36331 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
36334 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
36335 Return a service that runs the @command{dicod} daemon, an implementation
36336 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
36338 The optional @var{config} argument specifies the configuration for
36339 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
36340 default it serves the GNU Collaborative International Dictionary of English.
36342 You can add @command{open localhost} to your @file{~/.dico} file to make
36343 @code{localhost} the default server for @command{dico} client
36344 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
36347 @deftp {Data Type} dicod-configuration
36348 Data type representing the configuration of dicod.
36351 @item @code{dico} (default: @var{dico})
36352 Package object of the GNU Dico dictionary server.
36354 @item @code{interfaces} (default: @var{'("localhost")})
36355 This is the list of IP addresses and ports and possibly socket file
36356 names to listen to (@pxref{Server Settings, @code{listen} directive,,
36357 dico, GNU Dico Manual}).
36359 @item @code{handlers} (default: @var{'()})
36360 List of @code{<dicod-handler>} objects denoting handlers (module instances).
36362 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
36363 List of @code{<dicod-database>} objects denoting dictionaries to be served.
36367 @deftp {Data Type} dicod-handler
36368 Data type representing a dictionary handler (module instance).
36372 Name of the handler (module instance).
36374 @item @code{module} (default: @var{#f})
36375 Name of the dicod module of the handler (instance). If it is @code{#f},
36376 the module has the same name as the handler.
36377 (@pxref{Modules,,, dico, GNU Dico Manual}).
36379 @item @code{options}
36380 List of strings or gexps representing the arguments for the module handler
36384 @deftp {Data Type} dicod-database
36385 Data type representing a dictionary database.
36389 Name of the database, will be used in DICT commands.
36391 @item @code{handler}
36392 Name of the dicod handler (module instance) used by this database
36393 (@pxref{Handlers,,, dico, GNU Dico Manual}).
36395 @item @code{complex?} (default: @var{#f})
36396 Whether the database configuration complex. The complex configuration
36397 will need a corresponding @code{<dicod-handler>} object, otherwise not.
36399 @item @code{options}
36400 List of strings or gexps representing the arguments for the database
36401 (@pxref{Databases,,, dico, GNU Dico Manual}).
36405 @defvr {Scheme Variable} %dicod-database:gcide
36406 A @code{<dicod-database>} object serving the GNU Collaborative International
36407 Dictionary of English using the @code{gcide} package.
36410 The following is an example @code{dicod-service} configuration.
36413 (dicod-service #:config
36414 (dicod-configuration
36415 (handlers (list (dicod-handler
36419 (list #~(string-append "dbdir=" #$wordnet))))))
36420 (databases (list (dicod-database
36423 (handler "wordnet")
36424 (options '("database=wn")))
36425 %dicod-database:gcide))))
36429 @subsubheading Docker Service
36431 The @code{(gnu services docker)} module provides the following services.
36433 @defvr {Scheme Variable} docker-service-type
36435 This is the type of the service that runs @url{https://www.docker.com,Docker},
36436 a daemon that can execute application bundles (sometimes referred to as
36437 ``containers'') in isolated environments.
36441 @deftp {Data Type} docker-configuration
36442 This is the data type representing the configuration of Docker and Containerd.
36446 @item @code{docker} (default: @code{docker})
36447 The Docker daemon package to use.
36449 @item @code{docker-cli} (default: @code{docker-cli})
36450 The Docker client package to use.
36452 @item @code{containerd} (default: @var{containerd})
36453 The Containerd package to use.
36455 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
36456 The Docker user-land networking proxy package to use.
36458 @item @code{enable-proxy?} (default @code{#t})
36459 Enable or disable the use of the Docker user-land networking proxy.
36461 @item @code{debug?} (default @code{#f})
36462 Enable or disable debug output.
36464 @item @code{enable-iptables?} (default @code{#t})
36465 Enable or disable the addition of iptables rules.
36467 @item @code{environment-variables} (default: @code{()})
36468 List of environment variables to set for @command{dockerd}.
36470 This must be a list of strings where each string has the form
36471 @samp{@var{key}=@var{value}} as in this example:
36474 (list "LANGUAGE=eo:ca:eu"
36475 "TMPDIR=/tmp/dockerd")
36481 @cindex Singularity, container service
36482 @defvr {Scheme Variable} singularity-service-type
36483 This is the type of the service that allows you to run
36484 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
36485 create and run application bundles (aka. ``containers''). The value for this
36486 service is the Singularity package to use.
36488 The service does not install a daemon; instead, it installs helper programs as
36489 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
36490 @command{singularity run} and similar commands.
36494 @subsubheading Auditd Service
36496 The @code{(gnu services auditd)} module provides the following service.
36498 @defvr {Scheme Variable} auditd-service-type
36500 This is the type of the service that runs
36501 @url{https://people.redhat.com/sgrubb/audit/,auditd},
36502 a daemon that tracks security-relevant information on your system.
36504 Examples of things that can be tracked:
36514 Failed login attempts
36521 @command{auditctl} from the @code{audit} package can be used in order
36522 to add or remove events to be tracked (until the next reboot).
36523 In order to permanently track events, put the command line arguments
36524 of auditctl into a file called @code{audit.rules} in the configuration
36525 directory (see below).
36526 @command{aureport} from the @code{audit} package can be used in order
36527 to view a report of all recorded events.
36528 The audit daemon by default logs into the file
36529 @file{/var/log/audit.log}.
36533 @deftp {Data Type} auditd-configuration
36534 This is the data type representing the configuration of auditd.
36538 @item @code{audit} (default: @code{audit})
36539 The audit package to use.
36541 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
36542 The directory containing the configuration file for the audit package, which
36543 must be named @code{auditd.conf}, and optionally some audit rules to
36544 instantiate on startup.
36550 @subsubheading R-Shiny service
36552 The @code{(gnu services science)} module provides the following service.
36554 @defvr {Scheme Variable} rshiny-service-type
36556 This is a type of service which is used to run a webapp created with
36557 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
36558 variable and runs the provided script to call @code{runApp}.
36560 @deftp {Data Type} rshiny-configuration
36561 This is the data type representing the configuration of rshiny.
36565 @item @code{package} (default: @code{r-shiny})
36566 The package to use.
36568 @item @code{binary} (default @code{"rshiny"})
36569 The name of the binary or shell script located at @code{package/bin/} to
36570 run when the service is run.
36572 The common way to create this file is as follows:
36576 (let* ((out (assoc-ref %outputs "out"))
36577 (targetdir (string-append out "/share/" ,name))
36578 (app (string-append out "/bin/" ,name))
36579 (Rbin (search-input-file %build-inputs "/bin/Rscript")))
36581 (mkdir-p (string-append out "/bin"))
36582 (call-with-output-file app
36588 runApp(launch.browser=0, port=4202)~%\n"
36597 @subsubheading Nix service
36599 The @code{(gnu services nix)} module provides the following service.
36601 @defvr {Scheme Variable} nix-service-type
36603 This is the type of the service that runs build daemon of the
36604 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
36608 (use-modules (gnu))
36609 (use-service-modules nix)
36610 (use-package-modules package-management)
36614 (packages (append (list nix)
36617 (services (append (list (service nix-service-type))
36621 After @command{guix system reconfigure} configure Nix for your user:
36624 @item Add a Nix channel and update it. See
36625 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
36627 @item Create a symlink to your profile and activate Nix profile:
36631 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
36632 $ source /run/current-system/profile/etc/profile.d/nix.sh
36637 @deftp {Data Type} nix-configuration
36638 This data type represents the configuration of the Nix daemon.
36641 @item @code{nix} (default: @code{nix})
36642 The Nix package to use.
36644 @item @code{sandbox} (default: @code{#t})
36645 Specifies whether builds are sandboxed by default.
36647 @item @code{build-sandbox-items} (default: @code{'()})
36648 This is a list of strings or objects appended to the
36649 @code{build-sandbox-items} field of the configuration file.
36651 @item @code{extra-config} (default: @code{'()})
36652 This is a list of strings or objects appended to the configuration file.
36653 It is used to pass extra text to be added verbatim to the configuration
36656 @item @code{extra-options} (default: @code{'()})
36657 Extra command line options for @code{nix-service-type}.
36662 @subsubheading Fail2Ban service
36664 @uref{http://www.fail2ban.org/, @code{fail2ban}} scans log files
36665 (e.g. @code{/var/log/apache/error_log}) and bans IP addresses that show
36666 malicious signs -- repeated password failures, attempts to make use of
36669 @code{fail2ban-service-type} service type is provided by the @code{(gnu
36670 services security)} module.
36672 This service type runs the @code{fail2ban} daemon. It can be configured
36673 in various ways, which are:
36676 @item Basic configuration
36677 The basic parameters of the Fail2Ban service can be configured via its
36678 @code{fail2ban} configuration, which is documented below.
36680 @item User-specified jail extensions
36681 The @code{fail2ban-jail-service} function can be used to add new
36684 @item Shepherd extension mechanism
36685 Service developers can extend the @code{fail2ban-service-type} service
36686 type itself via the usual service extension mechanism.
36689 @defvr {Scheme Variable} fail2ban-service-type
36691 This is the type of the service that runs @code{fail2ban} daemon. Below
36692 is an example of a basic, explicit configuration:
36697 (service fail2ban-service-type
36698 (fail2ban-configuration
36701 (fail2ban-jail-configuration
36704 ;; There is no implicit dependency on an actual SSH
36705 ;; service, so you need to provide one.
36706 (service openssh-service-type))
36711 @deffn {Scheme Procedure} fail2ban-jail-service @var{svc-type} @var{jail}
36712 Extend @var{svc-type}, a @code{<service-type>} object with @var{jail}, a
36713 @code{fail2ban-jail-configuration} object.
36721 ;; The 'fail2ban-jail-service' procedure can extend any service type
36722 ;; with a fail2ban jail. This removes the requirement to explicitly
36723 ;; extend services with fail2ban-service-type.
36724 (fail2ban-jail-service
36725 openssh-service-type
36726 (fail2ban-jail-configuration
36729 (openssh-configuration ...))))
36733 Below is the reference for the different @code{jail-service-type}
36734 configuration records.
36736 @c The documentation is to be auto-generated via
36737 @c 'generate-documentation'. See at the bottom of (gnu services
36740 @deftp {Data Type} fail2ban-configuration
36741 Available @code{fail2ban-configuration} fields are:
36744 @item @code{fail2ban} (default: @code{fail2ban}) (type: package)
36745 The @code{fail2ban} package to use. It is used for both binaries and as
36746 base default configuration that is to be extended with
36747 @code{<fail2ban-jail-configuration>} objects.
36749 @item @code{run-directory} (default: @code{"/var/run/fail2ban"}) (type: string)
36750 The state directory for the @code{fail2ban} daemon.
36752 @item @code{jails} (default: @code{()}) (type: list-of-fail2ban-jail-configurations)
36753 Instances of @code{<fail2ban-jail-configuration>} collected from
36756 @item @code{extra-jails} (default: @code{()}) (type: list-of-fail2ban-jail-configurations)
36757 Instances of @code{<fail2ban-jail-configuration>} explicitly provided.
36759 @item @code{extra-content} (default: @code{()}) (type: text-config)
36760 Extra raw content to add to the end of the @file{jail.local} file,
36761 provided as a list of file-like objects.
36767 @deftp {Data Type} fail2ban-ignore-cache-configuration
36768 Available @code{fail2ban-ignore-cache-configuration} fields are:
36771 @item @code{key} (type: string)
36774 @item @code{max-count} (type: integer)
36777 @item @code{max-time} (type: integer)
36784 @deftp {Data Type} fail2ban-jail-action-configuration
36785 Available @code{fail2ban-jail-action-configuration} fields are:
36788 @item @code{name} (type: string)
36791 @item @code{arguments} (default: @code{()}) (type: list-of-arguments)
36798 @deftp {Data Type} fail2ban-jail-configuration
36799 Available @code{fail2ban-jail-configuration} fields are:
36802 @item @code{name} (type: string)
36803 Required name of this jail configuration.
36805 @item @code{enabled?} (default: @code{#t}) (type: boolean)
36806 Whether this jail is enabled.
36808 @item @code{backend} (type: maybe-symbol)
36809 Backend to use to detect changes in the @code{log-path}. The default is
36810 'auto. To consult the defaults of the jail configuration, refer to the
36811 @file{/etc/fail2ban/jail.conf} file of the @code{fail2ban} package.
36813 @item @code{max-retry} (type: maybe-integer)
36814 The number of failures before a host get banned (e.g. @code{(max-retry
36817 @item @code{max-matches} (type: maybe-integer)
36818 The number of matches stored in ticket (resolvable via tag
36819 @code{<matches>}) in action.
36821 @item @code{find-time} (type: maybe-string)
36822 The time window during which the maximum retry count must be reached for
36823 an IP address to be banned. A host is banned if it has generated
36824 @code{max-retry} during the last @code{find-time} seconds (e.g.
36825 @code{(find-time "10m")}). It can be provided in seconds or using
36826 Fail2Ban's "time abbreviation format", as described in @command{man 5
36829 @item @code{ban-time} (type: maybe-string)
36830 The duration, in seconds or time abbreviated format, that a ban should
36831 last. (e.g. @code{(ban-time "10m")}).
36833 @item @code{ban-time-increment?} (type: maybe-boolean)
36834 Whether to consider past bans to compute increases to the default ban
36835 time of a specific IP address.
36837 @item @code{ban-time-factor} (type: maybe-string)
36838 The coefficient to use to compute an exponentially growing ban time.
36840 @item @code{ban-time-formula} (type: maybe-string)
36841 This is the formula used to calculate the next value of a ban time.
36843 @item @code{ban-time-multipliers} (type: maybe-string)
36844 Used to calculate next value of ban time instead of formula.
36846 @item @code{ban-time-max-time} (type: maybe-string)
36847 The maximum number of seconds a ban should last.
36849 @item @code{ban-time-rnd-time} (type: maybe-string)
36850 The maximum number of seconds a randomized ban time should last. This
36851 can be useful to stop ``clever'' botnets calculating the exact time an
36852 IP address can be unbanned again.
36854 @item @code{ban-time-overall-jails?} (type: maybe-boolean)
36855 When true, it specifies the search of an IP address in the database
36856 should be made across all jails. Otherwise, only the current jail of
36857 the ban IP address is considered.
36859 @item @code{ignore-self?} (type: maybe-boolean)
36860 Never ban the local machine's own IP address.
36862 @item @code{ignore-ip} (default: @code{()}) (type: list-of-strings)
36863 A list of IP addresses, CIDR masks or DNS hosts to ignore.
36864 @code{fail2ban} will not ban a host which matches an address in this
36867 @item @code{ignore-cache} (type: maybe-fail2ban-ignore-cache-configuration)
36868 Provide cache parameters for the ignore failure check.
36870 @item @code{filter} (type: maybe-fail2ban-jail-filter-configuration)
36871 The filter to use by the jail, specified via a
36872 @code{<fail2ban-jail-filter-configuration>} object. By default, jails
36873 have names matching their filter name.
36875 @item @code{log-time-zone} (type: maybe-string)
36876 The default time zone for log lines that do not have one.
36878 @item @code{log-encoding} (type: maybe-symbol)
36879 The encoding of the log files handled by the jail. Possible values are:
36880 @code{'ascii}, @code{'utf-8} and @code{'auto}.
36882 @item @code{log-path} (default: @code{()}) (type: list-of-strings)
36883 The file names of the log files to be monitored.
36885 @item @code{action} (default: @code{()}) (type: list-of-fail2ban-jail-actions)
36886 A list of @code{<fail2ban-jail-action-configuration>}.
36888 @item @code{extra-content} (default: @code{()}) (type: text-config)
36889 Extra content for the jail configuration, provided as a list of file-like
36896 @deftp {Data Type} fail2ban-jail-filter-configuration
36897 Available @code{fail2ban-jail-filter-configuration} fields are:
36900 @item @code{name} (type: string)
36903 @item @code{mode} (type: maybe-string)
36910 @c End of auto-generated fail2ban documentation.
36912 @node Setuid Programs
36913 @section Setuid Programs
36915 @cindex setuid programs
36916 @cindex setgid programs
36917 Some programs need to run with elevated privileges, even when they are
36918 launched by unprivileged users. A notorious example is the
36919 @command{passwd} program, which users can run to change their
36920 password, and which needs to access the @file{/etc/passwd} and
36921 @file{/etc/shadow} files---something normally restricted to root, for
36922 obvious security reasons. To address that, @command{passwd} should be
36923 @dfn{setuid-root}, meaning that it always runs with root privileges
36924 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
36925 for more info about the setuid mechanism).
36927 The store itself @emph{cannot} contain setuid programs: that would be a
36928 security issue since any user on the system can write derivations that
36929 populate the store (@pxref{The Store}). Thus, a different mechanism is
36930 used: instead of changing the setuid or setgid bits directly on files that
36931 are in the store, we let the system administrator @emph{declare} which
36932 programs should be entrusted with these additional privileges.
36934 The @code{setuid-programs} field of an @code{operating-system}
36935 declaration contains a list of @code{<setuid-program>} denoting the
36936 names of programs to have a setuid or setgid bit set (@pxref{Using the
36937 Configuration System}). For instance, the @command{mount.nfs} program,
36938 which is part of the nfs-utils package, with a setuid root can be
36939 designated like this:
36943 (program (file-append nfs-utils "/sbin/mount.nfs")))
36946 And then, to make @command{mount.nfs} setuid on your system, add the
36947 previous example to your operating system declaration by appending it to
36948 @code{%setuid-programs} like this:
36952 ;; Some fields omitted...
36954 (append (list (setuid-program
36955 (program (file-append nfs-utils "/sbin/mount.nfs"))))
36956 %setuid-programs)))
36959 @deftp {Data Type} setuid-program
36960 This data type represents a program with a setuid or setgid bit set.
36963 @item @code{program}
36964 A file-like object having its setuid and/or setgid bit set.
36966 @item @code{setuid?} (default: @code{#t})
36967 Whether to set user setuid bit.
36969 @item @code{setgid?} (default: @code{#f})
36970 Whether to set group setgid bit.
36972 @item @code{user} (default: @code{0})
36973 UID (integer) or user name (string) for the user owner of the program,
36976 @item @code{group} (default: @code{0})
36977 GID (integer) goup name (string) for the group owner of the program,
36983 A default set of setuid programs is defined by the
36984 @code{%setuid-programs} variable of the @code{(gnu system)} module.
36986 @defvr {Scheme Variable} %setuid-programs
36987 A list of @code{<setuid-program>} denoting common programs that are
36990 The list includes commands such as @command{passwd}, @command{ping},
36991 @command{su}, and @command{sudo}.
36994 Under the hood, the actual setuid programs are created in the
36995 @file{/run/setuid-programs} directory at system activation time. The
36996 files in this directory refer to the ``real'' binaries, which are in the
36999 @node X.509 Certificates
37000 @section X.509 Certificates
37002 @cindex HTTPS, certificates
37003 @cindex X.509 certificates
37005 Web servers available over HTTPS (that is, HTTP over the transport-layer
37006 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
37007 that the client can then use to @emph{authenticate} the server. To do
37008 that, clients verify that the server's certificate is signed by a
37009 so-called @dfn{certificate authority} (CA). But to verify the CA's
37010 signature, clients must have first acquired the CA's certificate.
37012 Web browsers such as GNU@tie{}IceCat include their own set of CA
37013 certificates, such that they are able to verify CA signatures
37016 However, most other programs that can talk HTTPS---@command{wget},
37017 @command{git}, @command{w3m}, etc.---need to be told where CA
37018 certificates can be found.
37020 @cindex @code{nss-certs}
37021 In Guix, this is done by adding a package that provides certificates
37022 to the @code{packages} field of the @code{operating-system} declaration
37023 (@pxref{operating-system Reference}). Guix includes one such package,
37024 @code{nss-certs}, which is a set of CA certificates provided as part of
37025 Mozilla's Network Security Services.
37027 Note that it is @emph{not} part of @code{%base-packages}, so you need to
37028 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
37029 most applications and libraries look for certificates by default, points
37030 to the certificates installed globally.
37032 Unprivileged users, including users of Guix on a foreign distro,
37033 can also install their own certificate package in
37034 their profile. A number of environment variables need to be defined so
37035 that applications and libraries know where to find them. Namely, the
37036 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
37037 variables. Some applications add their own environment variables; for
37038 instance, the Git version control system honors the certificate bundle
37039 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
37040 would typically run something like:
37043 guix install nss-certs
37044 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
37045 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
37046 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
37049 As another example, R requires the @env{CURL_CA_BUNDLE} environment
37050 variable to point to a certificate bundle, so you would have to run
37051 something like this:
37054 guix install nss-certs
37055 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
37058 For other applications you may want to look up the required environment
37059 variable in the relevant documentation.
37062 @node Name Service Switch
37063 @section Name Service Switch
37065 @cindex name service switch
37067 The @code{(gnu system nss)} module provides bindings to the
37068 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
37069 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
37070 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
37071 extended with new ``name'' lookup methods for system databases, which
37072 includes host names, service names, user accounts, and more (@pxref{Name
37073 Service Switch, System Databases and Name Service Switch,, libc, The GNU
37074 C Library Reference Manual}).
37076 The NSS configuration specifies, for each system database, which lookup
37077 method is to be used, and how the various methods are chained
37078 together---for instance, under which circumstances NSS should try the
37079 next method in the list. The NSS configuration is given in the
37080 @code{name-service-switch} field of @code{operating-system} declarations
37081 (@pxref{operating-system Reference, @code{name-service-switch}}).
37084 @cindex .local, host name lookup
37085 As an example, the declaration below configures the NSS to use the
37086 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
37087 back-end}, which supports host name lookups over multicast DNS (mDNS)
37088 for host names ending in @code{.local}:
37091 (name-service-switch
37092 (hosts (list %files ;first, check /etc/hosts
37094 ;; If the above did not succeed, try
37095 ;; with 'mdns_minimal'.
37097 (name "mdns_minimal")
37099 ;; 'mdns_minimal' is authoritative for
37100 ;; '.local'. When it returns "not found",
37101 ;; no need to try the next methods.
37102 (reaction (lookup-specification
37103 (not-found => return))))
37105 ;; Then fall back to DNS.
37109 ;; Finally, try with the "full" 'mdns'.
37114 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
37115 contains this configuration, so you will not have to type it if all you
37116 want is to have @code{.local} host lookup working.
37118 Note that, in this case, in addition to setting the
37119 @code{name-service-switch} of the @code{operating-system} declaration,
37120 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
37121 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
37122 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
37123 to the name service cache daemon (@pxref{Base Services,
37124 @code{nscd-service}}).
37126 For convenience, the following variables provide typical NSS
37129 @defvr {Scheme Variable} %default-nss
37130 This is the default name service switch configuration, a
37131 @code{name-service-switch} object.
37134 @defvr {Scheme Variable} %mdns-host-lookup-nss
37135 This is the name service switch configuration with support for host name
37136 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
37139 The reference for name service switch configuration is given below. It
37140 is a direct mapping of the configuration file format of the C library , so
37141 please refer to the C library manual for more information (@pxref{NSS
37142 Configuration File,,, libc, The GNU C Library Reference Manual}).
37143 Compared to the configuration file format of libc NSS, it has the advantage
37144 not only of adding this warm parenthetic feel that we like, but also
37145 static checks: you will know about syntax errors and typos as soon as you
37146 run @command{guix system}.
37148 @deftp {Data Type} name-service-switch
37150 This is the data type representation the configuration of libc's name
37151 service switch (NSS). Each field below represents one of the supported
37168 The system databases handled by the NSS@. Each of these fields must be a
37169 list of @code{<name-service>} objects (see below).
37173 @deftp {Data Type} name-service
37175 This is the data type representing an actual name service and the
37176 associated lookup action.
37180 A string denoting the name service (@pxref{Services in the NSS
37181 configuration,,, libc, The GNU C Library Reference Manual}).
37183 Note that name services listed here must be visible to nscd. This is
37184 achieved by passing the @code{#:name-services} argument to
37185 @code{nscd-service} the list of packages providing the needed name
37186 services (@pxref{Base Services, @code{nscd-service}}).
37189 An action specified using the @code{lookup-specification} macro
37190 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
37191 Reference Manual}). For example:
37194 (lookup-specification (unavailable => continue)
37195 (success => return))
37200 @node Initial RAM Disk
37201 @section Initial RAM Disk
37204 @cindex initial RAM disk
37205 For bootstrapping purposes, the Linux-Libre kernel is passed an
37206 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
37207 root file system as well as an initialization script. The latter is
37208 responsible for mounting the real root file system, and for loading any
37209 kernel modules that may be needed to achieve that.
37211 The @code{initrd-modules} field of an @code{operating-system}
37212 declaration allows you to specify Linux-libre kernel modules that must
37213 be available in the initrd. In particular, this is where you would list
37214 modules needed to actually drive the hard disk where your root partition
37215 is---although the default value of @code{initrd-modules} should cover
37216 most use cases. For example, assuming you need the @code{megaraid_sas}
37217 module in addition to the default modules to be able to access your root
37218 file system, you would write:
37223 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
37226 @defvr {Scheme Variable} %base-initrd-modules
37227 This is the list of kernel modules included in the initrd by default.
37230 Furthermore, if you need lower-level customization, the @code{initrd}
37231 field of an @code{operating-system} declaration allows
37232 you to specify which initrd you would like to use. The @code{(gnu
37233 system linux-initrd)} module provides three ways to build an initrd: the
37234 high-level @code{base-initrd} procedure and the low-level
37235 @code{raw-initrd} and @code{expression->initrd} procedures.
37237 The @code{base-initrd} procedure is intended to cover most common uses.
37238 For example, if you want to add a bunch of kernel modules to be loaded
37239 at boot time, you can define the @code{initrd} field of the operating
37240 system declaration like this:
37243 (initrd (lambda (file-systems . rest)
37244 ;; Create a standard initrd but set up networking
37245 ;; with the parameters QEMU expects by default.
37246 (apply base-initrd file-systems
37247 #:qemu-networking? #t
37251 The @code{base-initrd} procedure also handles common use cases that
37252 involves using the system as a QEMU guest, or as a ``live'' system with
37253 volatile root file system.
37255 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
37256 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
37257 such as trying to guess which kernel modules and packages should be included
37258 to the initrd. An example use of @code{raw-initrd} is when a user has
37259 a custom Linux kernel configuration and default kernel modules included by
37260 @code{base-initrd} are not available.
37262 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
37263 honors several options passed on the Linux kernel command line
37264 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
37265 @code{-append} option of QEMU), notably:
37268 @item gnu.load=@var{boot}
37269 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
37270 program, once it has mounted the root file system.
37272 Guix uses this option to yield control to a boot program that runs the
37273 service activation programs and then spawns the GNU@tie{}Shepherd, the
37274 initialization system.
37276 @item root=@var{root}
37277 Mount @var{root} as the root file system. @var{root} can be a device
37278 name like @code{/dev/sda1}, a file system label, or a file system UUID.
37279 When unspecified, the device name from the root file system of the
37280 operating system declaration is used.
37282 @item rootfstype=@var{type}
37283 Set the type of the root file system. It overrides the @code{type}
37284 field of the root file system specified via the @code{operating-system}
37285 declaration, if any.
37287 @item rootflags=@var{options}
37288 Set the mount @emph{options} of the root file system. It overrides the
37289 @code{options} field of the root file system specified via the
37290 @code{operating-system} declaration, if any.
37292 @item fsck.mode=@var{mode}
37293 Whether to check the @var{root} file system for errors before mounting
37294 it. @var{mode} is one of @code{skip} (never check), @code{force} (always
37295 check), or @code{auto} to respect the root @code{<file-system>} object's
37296 @code{check?} setting (@pxref{File Systems}) and run a full scan only if
37297 the file system was not cleanly shut down.
37299 @code{auto} is the default if this option is not present or if @var{mode}
37300 is not one of the above.
37302 @item fsck.repair=@var{level}
37303 The level of repairs to perform automatically if errors are found in the
37304 @var{root} file system. @var{level} is one of @code{no} (do not write to
37305 @var{root} at all if possible), @code{yes} (repair as much as possible),
37306 or @code{preen} to repair problems considered safe to repair automatically.
37308 @code{preen} is the default if this option is not present or if @var{level}
37309 is not one of the above.
37311 @item gnu.system=@var{system}
37312 Have @file{/run/booted-system} and @file{/run/current-system} point to
37315 @item modprobe.blacklist=@var{modules}@dots{}
37316 @cindex module, black-listing
37317 @cindex black list, of kernel modules
37318 Instruct the initial RAM disk as well as the @command{modprobe} command
37319 (from the kmod package) to refuse to load @var{modules}. @var{modules}
37320 must be a comma-separated list of module names---e.g.,
37321 @code{usbkbd,9pnet}.
37324 Start a read-eval-print loop (REPL) from the initial RAM disk before it
37325 tries to load kernel modules and to mount the root file system. Our
37326 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
37327 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
37328 Manual}, for more information on Guile's REPL.
37332 Now that you know all the features that initial RAM disks produced by
37333 @code{base-initrd} and @code{raw-initrd} provide,
37334 here is how to use it and customize it further.
37337 @cindex initial RAM disk
37338 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
37339 [#:linux-modules '()] [#:mapped-devices '()] @
37340 [#:keyboard-layout #f] @
37341 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
37342 Return a derivation that builds a raw initrd. @var{file-systems} is
37343 a list of file systems to be mounted by the initrd, possibly in addition to
37344 the root file system specified on the kernel command line via @option{root}.
37345 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
37346 @var{mapped-devices} is a list of device mappings to realize before
37347 @var{file-systems} are mounted (@pxref{Mapped Devices}).
37348 @var{helper-packages} is a list of packages to be copied in the initrd.
37350 include @code{e2fsck/static} or other packages needed by the initrd to check
37351 the root file system.
37353 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
37354 the desired console keyboard layout. This is done before @var{mapped-devices}
37355 are set up and before @var{file-systems} are mounted such that, should the
37356 user need to enter a passphrase or use the REPL, this happens using the
37357 intended keyboard layout.
37359 When @var{qemu-networking?} is true, set up networking with the standard QEMU
37360 parameters. When @var{virtio?} is true, load additional modules so that the
37361 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
37363 When @var{volatile-root?} is true, the root file system is writable but any changes
37367 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
37368 [#:mapped-devices '()] [#:keyboard-layout #f] @
37369 [#:qemu-networking? #f] [#:volatile-root? #f] @
37370 [#:linux-modules '()]
37371 Return as a file-like object a generic initrd, with kernel
37372 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
37373 mounted by the initrd, possibly in addition to the root file system specified
37374 on the kernel command line via @option{root}. @var{mapped-devices} is a list of device
37375 mappings to realize before @var{file-systems} are mounted.
37377 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
37378 the desired console keyboard layout. This is done before @var{mapped-devices}
37379 are set up and before @var{file-systems} are mounted such that, should the
37380 user need to enter a passphrase or use the REPL, this happens using the
37381 intended keyboard layout.
37383 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
37385 The initrd is automatically populated with all the kernel modules necessary
37386 for @var{file-systems} and for the given options. Additional kernel
37387 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
37388 loaded at boot time in the order in which they appear.
37391 Needless to say, the initrds we produce and use embed a
37392 statically-linked Guile, and the initialization program is a Guile
37393 program. That gives a lot of flexibility. The
37394 @code{expression->initrd} procedure builds such an initrd, given the
37395 program to run in that initrd.
37397 @deffn {Scheme Procedure} expression->initrd @var{exp} @
37398 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
37399 Return as a file-like object a Linux initrd (a gzipped cpio archive)
37400 containing @var{guile} and that evaluates @var{exp}, a G-expression,
37401 upon booting. All the derivations referenced by @var{exp} are
37402 automatically copied to the initrd.
37405 @node Bootloader Configuration
37406 @section Bootloader Configuration
37409 @cindex boot loader
37411 The operating system supports multiple bootloaders. The bootloader is
37412 configured using @code{bootloader-configuration} declaration. All the
37413 fields of this structure are bootloader agnostic except for one field,
37414 @code{bootloader} that indicates the bootloader to be configured and
37417 Some of the bootloaders do not honor every field of
37418 @code{bootloader-configuration}. For instance, the extlinux
37419 bootloader does not support themes and thus ignores the @code{theme}
37422 @deftp {Data Type} bootloader-configuration
37423 The type of a bootloader configuration declaration.
37427 @item @code{bootloader}
37428 @cindex EFI, bootloader
37429 @cindex UEFI, bootloader
37430 @cindex BIOS, bootloader
37431 The bootloader to use, as a @code{bootloader} object. For now
37432 @code{grub-bootloader}, @code{grub-efi-bootloader},
37433 @code{grub-efi-netboot-bootloader}, @code{grub-efi-removable-bootloader},
37434 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
37436 @cindex ARM, bootloaders
37437 @cindex AArch64, bootloaders
37438 Available bootloaders are described in @code{(gnu bootloader @dots{})}
37439 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
37440 of bootloaders for a wide range of ARM and AArch64 systems, using the
37441 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
37443 @vindex grub-efi-bootloader
37444 @code{grub-efi-bootloader} allows to boot on modern systems using the
37445 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
37446 use if the installation image contains a @file{/sys/firmware/efi} directory
37447 when you boot it on your system.
37449 @vindex grub-bootloader
37450 @code{grub-bootloader} allows you to boot in particular Intel-based machines
37451 in ``legacy'' BIOS mode.
37453 @vindex grub-efi-netboot-bootloader
37454 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
37455 through TFTP@. In combination with an NFS root file system this allows you to
37456 build a diskless Guix system.
37458 The installation of the @code{grub-efi-netboot-bootloader} generates the
37459 content of the TFTP root directory at @code{targets} (@pxref{Bootloader
37460 Configuration, @code{targets}}), to be served by a TFTP server. You may
37461 want to mount your TFTP server directories onto the @code{targets} to
37462 move the required files to the TFTP server automatically.
37464 If you plan to use an NFS root file system as well (actually if you mount the
37465 store from an NFS share), then the TFTP server needs to serve the file
37466 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
37467 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
37468 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
37469 files from the store will be accessed by GRUB through TFTP with their normal
37470 store path, for example as
37471 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
37473 Two symlinks are created to make this possible. For each target in the
37474 @code{targets} field, the first symlink is
37475 @samp{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
37476 @file{../../../boot/grub/grub.cfg}, where @samp{target} may be
37477 @file{/boot}. In this case the link is not leaving the served TFTP root
37478 directory, but otherwise it does. The second link is
37479 @samp{target}@file{/gnu/store} and points to @file{../gnu/store}. This
37480 link is leaving the served TFTP root directory.
37482 The assumption behind all this is that you have an NFS server exporting
37483 the root file system for your Guix system, and additionally a TFTP
37484 server exporting your @code{targets} directories—usually a single
37485 @file{/boot}—from that same root file system for your Guix system. In
37486 this constellation the symlinks will work.
37488 For other constellations you will have to program your own bootloader
37489 installer, which then takes care to make necessary files from the store
37490 accessible through TFTP, for example by copying them into the TFTP root
37491 directory to your @code{targets}.
37493 It is important to note that symlinks pointing outside the TFTP root directory
37494 may need to be allowed in the configuration of your TFTP server. Further the
37495 store link exposes the whole store through TFTP@. Both points need to be
37496 considered carefully for security aspects.
37498 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
37499 NFS servers, you also need a properly configured DHCP server to make the booting
37500 over netboot possible. For all this we can currently only recommend you to look
37501 for instructions about @acronym{PXE, Preboot eXecution Environment}.
37503 @vindex grub-efi-removable-bootloader
37504 @code{grub-efi-removable-bootloader} allows you to boot your system from
37505 removable media by writing the GRUB file to the UEFI-specification location of
37506 @file{/EFI/BOOT/BOOTX64.efi} of the boot directory, usually @file{/boot/efi}.
37507 This is also useful for some UEFI firmwares that ``forget'' their configuration
37508 from their non-volatile storage. Like @code{grub-efi-bootloader}, this can only
37509 be used if the @file{/sys/firmware/efi} directory is available.
37512 This @emph{will} overwrite the GRUB file from any other operating systems that
37513 also place their GRUB file in the UEFI-specification location; making them
37517 @item @code{targets}
37518 This is a list of strings denoting the targets onto which to install the
37521 The interpretation of targets depends on the bootloader in question.
37522 For @code{grub-bootloader}, for example, they should be device names
37523 understood by the bootloader @command{installer} command, such as
37524 @code{/dev/sda} or @code{(hd0)} (@pxref{Invoking grub-install,,, grub,
37525 GNU GRUB Manual}). For @code{grub-efi-bootloader} and
37526 @code{grub-efi-removable-bootloader} they should be mount
37527 points of the EFI file system, usually @file{/boot/efi}. For
37528 @code{grub-efi-netboot-bootloader}, @code{targets} should be the mount
37529 points corresponding to TFTP root directories served by your TFTP
37532 @item @code{menu-entries} (default: @code{()})
37533 A possibly empty list of @code{menu-entry} objects (see below), denoting
37534 entries to appear in the bootloader menu, in addition to the current
37535 system entry and the entry pointing to previous system generations.
37537 @item @code{default-entry} (default: @code{0})
37538 The index of the default boot menu entry. Index 0 is for the entry of the
37541 @item @code{timeout} (default: @code{5})
37542 The number of seconds to wait for keyboard input before booting. Set to
37543 0 to boot immediately, and to -1 to wait indefinitely.
37545 @cindex keyboard layout, for the bootloader
37546 @item @code{keyboard-layout} (default: @code{#f})
37547 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
37548 layout, usually US@tie{}English (``qwerty'').
37550 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
37554 This option is currently ignored by bootloaders other than @code{grub} and
37558 @item @code{theme} (default: @var{#f})
37559 The bootloader theme object describing the theme to use. If no theme
37560 is provided, some bootloaders might use a default theme, that's true
37563 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
37564 The output terminals used for the bootloader boot menu, as a list of
37565 symbols. GRUB accepts the values: @code{console}, @code{serial},
37566 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
37567 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
37568 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
37569 configuration,,, grub,GNU GRUB manual}).
37571 @item @code{terminal-inputs} (default: @code{'()})
37572 The input terminals used for the bootloader boot menu, as a list of
37573 symbols. For GRUB, the default is the native platform terminal as
37574 determined at run-time. GRUB accepts the values: @code{console},
37575 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
37576 @code{usb_keyboard}. This field corresponds to the GRUB variable
37577 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
37580 @item @code{serial-unit} (default: @code{#f})
37581 The serial unit used by the bootloader, as an integer from 0 to 3.
37582 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
37583 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
37585 @item @code{serial-speed} (default: @code{#f})
37586 The speed of the serial interface, as an integer. For GRUB, the
37587 default value is chosen at run-time; currently GRUB chooses
37588 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
37590 @item @code{device-tree-support?} (default: @code{#t})
37591 Whether to support Linux @uref{https://en.wikipedia.org/wiki/Devicetree,
37592 device tree} files loading.
37594 This option in enabled by default. In some cases involving the
37595 @code{u-boot} bootloader, where the device tree has already been loaded
37596 in RAM, it can be handy to disable the option by setting it to
37604 Should you want to list additional boot menu entries @i{via} the
37605 @code{menu-entries} field above, you will need to create them with the
37606 @code{menu-entry} form. For example, imagine you want to be able to
37607 boot another distro (hard to imagine!), you can define a menu entry
37612 (label "The Other Distro")
37613 (linux "/boot/old/vmlinux-2.6.32")
37614 (linux-arguments '("root=/dev/sda2"))
37615 (initrd "/boot/old/initrd"))
37620 @deftp {Data Type} menu-entry
37621 The type of an entry in the bootloader menu.
37626 The label to show in the menu---e.g., @code{"GNU"}.
37628 @item @code{linux} (default: @code{#f})
37629 The Linux kernel image to boot, for example:
37632 (file-append linux-libre "/bzImage")
37635 For GRUB, it is also possible to specify a device explicitly in the
37636 file path using GRUB's device naming convention (@pxref{Naming
37637 convention,,, grub, GNU GRUB manual}), for example:
37640 "(hd0,msdos1)/boot/vmlinuz"
37643 If the device is specified explicitly as above, then the @code{device}
37644 field is ignored entirely.
37646 @item @code{linux-arguments} (default: @code{()})
37647 The list of extra Linux kernel command-line arguments---e.g.,
37648 @code{("console=ttyS0")}.
37650 @item @code{initrd} (default: @code{#f})
37651 A G-Expression or string denoting the file name of the initial RAM disk
37652 to use (@pxref{G-Expressions}).
37654 @item @code{device} (default: @code{#f})
37655 The device where the kernel and initrd are to be found---i.e., for GRUB,
37656 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
37658 This may be a file system label (a string), a file system UUID (a
37659 bytevector, @pxref{File Systems}), or @code{#f}, in which case
37660 the bootloader will search the device containing the file specified by
37661 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
37662 must @emph{not} be an OS device name such as @file{/dev/sda1}.
37664 @item @code{multiboot-kernel} (default: @code{#f})
37665 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
37666 manual}). When this field is set, a Multiboot menu-entry is generated.
37670 (file-append mach "/boot/gnumach")
37673 @item @code{multiboot-arguments} (default: @code{()})
37674 The list of extra command-line arguments for the multiboot-kernel.
37676 @item @code{multiboot-modules} (default: @code{()})
37677 The list of commands for loading Multiboot modules. For example:
37680 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
37682 (list (file-append libc "/lib/ld.so.1") "exec"
37686 @item @code{chain-loader} (default: @code{#f})
37687 A string that can be accepted by @code{grub}'s @code{chainloader}
37688 directive. This has no effect if either @code{linux} or
37689 @code{multiboot-kernel} fields are specified. The following is an
37690 example of chainloading a different GNU/Linux system.
37694 (bootloader-configuration
37699 (label "GNU/Linux")
37700 (device (uuid "1C31-A17C" 'fat))
37701 (chain-loader "/EFI/GNULinux/grubx64.efi"))))))
37710 @c FIXME: Write documentation once it's stable.
37711 For now only GRUB has theme support. GRUB themes are created using
37712 the @code{grub-theme} form, which is not fully documented yet.
37714 @deftp {Data Type} grub-theme
37715 Data type representing the configuration of the GRUB theme.
37718 @item @code{gfxmode} (default: @code{'("auto")})
37719 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
37720 @pxref{gfxmode,,, grub, GNU GRUB manual}).
37724 @deffn {Scheme Procedure} grub-theme
37725 Return the default GRUB theme used by the operating system if no
37726 @code{theme} field is specified in @code{bootloader-configuration}
37729 It comes with a fancy background image displaying the GNU and Guix
37733 For example, to override the default resolution, you may use something
37738 (bootloader-configuration
37741 (inherit (grub-theme))
37742 (gfxmode '("1024x786x32" "auto"))))))
37745 @node Invoking guix system
37746 @section Invoking @code{guix system}
37748 Once you have written an operating system declaration as seen in the
37749 previous section, it can be @dfn{instantiated} using the @command{guix
37750 system} command. The synopsis is:
37753 guix system @var{options}@dots{} @var{action} @var{file}
37756 @var{file} must be the name of a file containing an
37757 @code{operating-system} declaration. @var{action} specifies how the
37758 operating system is instantiated. Currently the following values are
37763 Display available service type definitions that match the given regular
37764 expressions, sorted by relevance:
37770 $ guix system search console
37771 name: console-fonts
37772 location: gnu/services/base.scm:806:2
37773 extends: shepherd-root
37774 description: Install the given fonts on the specified ttys (fonts are per
37775 + virtual console on GNU/Linux). The value of this service is a list of
37776 + tty/font pairs. The font can be the name of a font provided by the `kbd'
37777 + package or any valid argument to `setfont', as in this example:
37779 + '(("tty1" . "LatGrkCyr-8x16")
37780 + ("tty2" . (file-append
37782 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
37783 + ("tty3" . (file-append
37785 + "/share/consolefonts/ter-132n"))) ; for HDPI
37789 location: gnu/services/base.scm:1190:2
37790 extends: shepherd-root
37791 description: Provide console login using the `mingetty' program.
37795 location: gnu/services/base.scm:860:2
37797 description: Provide a console log-in service as specified by its
37798 + configuration value, a `login-configuration' object.
37804 As for @command{guix package --search}, the result is written in
37805 @code{recutils} format, which makes it easy to filter the output
37806 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
37808 @cindex service type definition, editing
37809 @cindex editing, service type definition
37811 Edit or view the definition of the given service types.
37813 For example, the command below opens your editor, as specified by the
37814 @env{EDITOR} environment variable, on the definition of the
37815 @code{openssh} service type:
37818 guix system edit openssh
37822 Build the operating system described in @var{file}, activate it, and
37823 switch to it@footnote{This action (and the related actions
37824 @code{switch-generation} and @code{roll-back}) are usable only on
37825 systems already running Guix System.}.
37828 @c The paragraph below refers to the problem discussed at
37829 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
37830 It is highly recommended to run @command{guix pull} once before you run
37831 @command{guix system reconfigure} for the first time (@pxref{Invoking
37832 guix pull}). Failing to do that you would see an older version of Guix
37833 once @command{reconfigure} has completed.
37836 This effects all the configuration specified in @var{file}: user
37837 accounts, system services, global package list, setuid programs, etc.
37838 The command starts system services specified in @var{file} that are not
37839 currently running; if a service is currently running this command will
37840 arrange for it to be upgraded the next time it is stopped (e.g.@: by
37841 @code{herd stop X} or @code{herd restart X}).
37843 This command creates a new generation whose number is one greater than
37844 the current generation (as reported by @command{guix system
37845 list-generations}). If that generation already exists, it will be
37846 overwritten. This behavior mirrors that of @command{guix package}
37847 (@pxref{Invoking guix package}).
37849 It also adds a bootloader menu entry for the new OS configuration,
37850 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
37851 entries for older configurations to a submenu, allowing you to choose
37852 an older system generation at boot time should you need it.
37854 @cindex provenance tracking, of the operating system
37855 Upon completion, the new system is deployed under
37856 @file{/run/current-system}. This directory contains @dfn{provenance
37857 meta-data}: the list of channels in use (@pxref{Channels}) and
37858 @var{file} itself, when available. You can view it by running:
37861 guix system describe
37864 This information is useful should you later want to inspect how this
37865 particular generation was built. In fact, assuming @var{file} is
37866 self-contained, you can later rebuild generation @var{n} of your
37867 operating system with:
37870 guix time-machine \
37871 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
37872 system reconfigure \
37873 /var/guix/profiles/system-@var{n}-link/configuration.scm
37876 You can think of it as some sort of built-in version control! Your
37877 system is not just a binary artifact: @emph{it carries its own source}.
37878 @xref{Service Reference, @code{provenance-service-type}}, for more
37879 information on provenance tracking.
37881 By default, @command{reconfigure} @emph{prevents you from downgrading
37882 your system}, which could (re)introduce security vulnerabilities and
37883 also cause problems with ``stateful'' services such as database
37884 management systems. You can override that behavior by passing
37885 @option{--allow-downgrades}.
37887 @item switch-generation
37888 @cindex generations
37889 Switch to an existing system generation. This action atomically
37890 switches the system profile to the specified system generation. It
37891 also rearranges the system's existing bootloader menu entries. It
37892 makes the menu entry for the specified system generation the default,
37893 and it moves the entries for the other generations to a submenu, if
37894 supported by the bootloader being used. The next time the system
37895 boots, it will use the specified system generation.
37897 The bootloader itself is not being reinstalled when using this
37898 command. Thus, the installed bootloader is used with an updated
37899 configuration file.
37901 The target generation can be specified explicitly by its generation
37902 number. For example, the following invocation would switch to system
37906 guix system switch-generation 7
37909 The target generation can also be specified relative to the current
37910 generation with the form @code{+N} or @code{-N}, where @code{+3} means
37911 ``3 generations ahead of the current generation,'' and @code{-1} means
37912 ``1 generation prior to the current generation.'' When specifying a
37913 negative value such as @code{-1}, you must precede it with @code{--} to
37914 prevent it from being parsed as an option. For example:
37917 guix system switch-generation -- -1
37920 Currently, the effect of invoking this action is @emph{only} to switch
37921 the system profile to an existing generation and rearrange the
37922 bootloader menu entries. To actually start using the target system
37923 generation, you must reboot after running this action. In the future,
37924 it will be updated to do the same things as @command{reconfigure},
37925 like activating and deactivating services.
37927 This action will fail if the specified generation does not exist.
37930 @cindex rolling back
37931 Switch to the preceding system generation. The next time the system
37932 boots, it will use the preceding system generation. This is the inverse
37933 of @command{reconfigure}, and it is exactly the same as invoking
37934 @command{switch-generation} with an argument of @code{-1}.
37936 Currently, as with @command{switch-generation}, you must reboot after
37937 running this action to actually start using the preceding system
37940 @item delete-generations
37941 @cindex deleting system generations
37942 @cindex saving space
37943 Delete system generations, making them candidates for garbage collection
37944 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
37947 This works in the same way as @samp{guix package --delete-generations}
37948 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
37949 arguments, all system generations but the current one are deleted:
37952 guix system delete-generations
37955 You can also select the generations you want to delete. The example below
37956 deletes all the system generations that are more than two months old:
37959 guix system delete-generations 2m
37962 Running this command automatically reinstalls the bootloader with an updated
37963 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
37964 longer lists the generations that have been deleted.
37967 Build the derivation of the operating system, which includes all the
37968 configuration files and programs needed to boot and run the system.
37969 This action does not actually install anything.
37972 Populate the given directory with all the files necessary to run the
37973 operating system specified in @var{file}. This is useful for first-time
37974 installations of Guix System. For instance:
37977 guix system init my-os-config.scm /mnt
37980 copies to @file{/mnt} all the store items required by the configuration
37981 specified in @file{my-os-config.scm}. This includes configuration
37982 files, packages, and so on. It also creates other essential files
37983 needed for the system to operate correctly---e.g., the @file{/etc},
37984 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
37986 This command also installs bootloader on the targets specified in
37987 @file{my-os-config}, unless the @option{--no-bootloader} option was
37991 @cindex virtual machine
37993 @anchor{guix system vm}
37994 Build a virtual machine (VM) that contains the operating system declared
37995 in @var{file}, and return a script to run that VM.
37998 The @code{vm} action and others below
37999 can use KVM support in the Linux-libre kernel. Specifically, if the
38000 machine has hardware virtualization support, the corresponding
38001 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
38002 must exist and be readable and writable by the user and by the
38003 build users of the daemon (@pxref{Build Environment Setup}).
38006 Arguments given to the script are passed to QEMU as in the example
38007 below, which enables networking and requests 1@tie{}GiB of RAM for the
38011 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -nic user,model=virtio-net-pci
38014 It's possible to combine the two steps into one:
38017 $ $(guix system vm my-config.scm) -m 1024 -smp 2 -nic user,model=virtio-net-pci
38020 The VM shares its store with the host system.
38022 By default, the root file system of the VM is mounted volatile; the
38023 @option{--persistent} option can be provided to make it persistent
38024 instead. In that case, the VM disk-image file will be copied from the
38025 store to the @env{TMPDIR} directory to make it writable.
38027 Additional file systems can be shared between the host and the VM using
38028 the @option{--share} and @option{--expose} command-line options: the former
38029 specifies a directory to be shared with write access, while the latter
38030 provides read-only access to the shared directory.
38032 The example below creates a VM in which the user's home directory is
38033 accessible read-only, and where the @file{/exchange} directory is a
38034 read-write mapping of @file{$HOME/tmp} on the host:
38037 guix system vm my-config.scm \
38038 --expose=$HOME --share=$HOME/tmp=/exchange
38041 On GNU/Linux, the default is to boot directly to the kernel; this has
38042 the advantage of requiring only a very tiny root disk image since the
38043 store of the host can then be mounted.
38045 The @option{--full-boot} option forces a complete boot sequence, starting
38046 with the bootloader. This requires more disk space since a root image
38047 containing at least the kernel, initrd, and bootloader data files must
38050 The @option{--image-size} option can be used to specify the size of the
38053 The @option{--no-graphic} option will instruct @command{guix system} to
38054 spawn a headless VM that will use the invoking tty for IO. Among other
38055 things, this enables copy-pasting, and scrollback. Use the @kbd{ctrl-a}
38056 prefix to issue QEMU commands; e.g. @kbd{ctrl-a h} prints a help,
38057 @kbd{ctrl-a x} quits the VM, and @kbd{ctrl-a c} switches between the
38058 QEMU monitor and the VM.
38060 @cindex System images, creation in various formats
38061 @cindex Creating system images in various formats
38063 @cindex image, creating disk images
38064 The @code{image} command can produce various image types. The image
38065 type can be selected using the @option{--image-type} option. It
38066 defaults to @code{efi-raw}. When its value is @code{iso9660}, the
38067 @option{--label} option can be used to specify a volume ID with
38068 @code{image}. By default, the root file system of a disk image is
38069 mounted non-volatile; the @option{--volatile} option can be provided to
38070 make it volatile instead. When using @code{image}, the bootloader
38071 installed on the generated image is taken from the provided
38072 @code{operating-system} definition. The following example demonstrates
38073 how to generate an image that uses the @code{grub-efi-bootloader}
38074 bootloader and boot it with QEMU:
38077 image=$(guix system image --image-type=qcow2 \
38078 gnu/system/examples/lightweight-desktop.tmpl)
38079 cp $image /tmp/my-image.qcow2
38080 chmod +w /tmp/my-image.qcow2
38081 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
38082 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
38085 When using the @code{efi-raw} image type, a raw disk image is produced;
38086 it can be copied as is to a USB stick, for instance. Assuming
38087 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
38088 the image to it using the following command:
38091 # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
38094 The @code{--list-image-types} command lists all the available image
38097 @cindex creating virtual machine images
38098 When using the @code{qcow2} image type, the returned image is in qcow2
38099 format, which the QEMU emulator can efficiently use. @xref{Running Guix
38100 in a VM}, for more information on how to run the image in a virtual
38101 machine. The @code{grub-bootloader} bootloader is always used
38102 independently of what is declared in the @code{operating-system} file
38103 passed as argument. This is to make it easier to work with QEMU, which
38104 uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
38105 in the Master Boot Record (MBR).
38107 @cindex docker-image, creating docker images
38108 When using the @code{docker} image type, a Docker image is produced.
38109 Guix builds the image from scratch, not from a pre-existing Docker base
38110 image. As a result, it contains @emph{exactly} what you define in the
38111 operating system configuration file. You can then load the image and
38112 launch a Docker container using commands like the following:
38115 image_id="$(docker load < guix-system-docker-image.tar.gz)"
38116 container_id="$(docker create $image_id)"
38117 docker start $container_id
38120 This command starts a new Docker container from the specified image. It
38121 will boot the Guix system in the usual manner, which means it will
38122 start any services you have defined in the operating system
38123 configuration. You can get an interactive shell running in the container
38124 using @command{docker exec}:
38127 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
38130 Depending on what you run in the Docker container, it
38131 may be necessary to give the container additional permissions. For
38132 example, if you intend to build software using Guix inside of the Docker
38133 container, you may need to pass the @option{--privileged} option to
38134 @code{docker create}.
38136 Last, the @option{--network} option applies to @command{guix system
38137 docker-image}: it produces an image where network is supposedly shared
38138 with the host, and thus without services like nscd or NetworkManager.
38141 Return a script to run the operating system declared in @var{file}
38142 within a container. Containers are a set of lightweight isolation
38143 mechanisms provided by the kernel Linux-libre. Containers are
38144 substantially less resource-demanding than full virtual machines since
38145 the kernel, shared objects, and other resources can be shared with the
38146 host system; this also means they provide thinner isolation.
38148 Currently, the script must be run as root in order to support more than
38149 a single user and group. The container shares its store with the host
38152 As with the @code{vm} action (@pxref{guix system vm}), additional file
38153 systems to be shared between the host and container can be specified
38154 using the @option{--share} and @option{--expose} options:
38157 guix system container my-config.scm \
38158 --expose=$HOME --share=$HOME/tmp=/exchange
38161 The @option{--share} and @option{--expose} options can also be passed to
38162 the generated script to bind-mount additional directories into the
38166 This option requires Linux-libre 3.19 or newer.
38171 @var{options} can contain any of the common build options (@pxref{Common
38172 Build Options}). In addition, @var{options} can contain one of the
38176 @item --expression=@var{expr}
38177 @itemx -e @var{expr}
38178 Consider the operating-system @var{expr} evaluates to.
38179 This is an alternative to specifying a file which evaluates to an
38181 This is used to generate the Guix system installer @pxref{Building the
38182 Installation Image}).
38184 @item --system=@var{system}
38185 @itemx -s @var{system}
38186 Attempt to build for @var{system} instead of the host system type.
38187 This works as per @command{guix build} (@pxref{Invoking guix build}).
38189 @item --target=@var{triplet}
38190 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
38191 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
38192 configuration triplets,, autoconf, Autoconf}).
38196 Return the derivation file name of the given operating system without
38199 @cindex provenance tracking, of the operating system
38200 @item --save-provenance
38201 As discussed above, @command{guix system init} and @command{guix system
38202 reconfigure} always save provenance information @i{via} a dedicated
38203 service (@pxref{Service Reference, @code{provenance-service-type}}).
38204 However, other commands don't do that by default. If you wish to, say,
38205 create a virtual machine image that contains provenance information, you
38209 guix system image -t qcow2 --save-provenance config.scm
38212 That way, the resulting image will effectively ``embed its own source''
38213 in the form of meta-data in @file{/run/current-system}. With that
38214 information, one can rebuild the image to make sure it really contains
38215 what it pretends to contain; or they could use that to derive a variant
38218 @item --image-type=@var{type}
38219 @itemx -t @var{type}
38220 For the @code{image} action, create an image with given @var{type}.
38222 When this option is omitted, @command{guix system} uses the
38223 @code{efi-raw} image type.
38225 @cindex ISO-9660 format
38226 @cindex CD image format
38227 @cindex DVD image format
38228 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
38229 for burning on CDs and DVDs.
38231 @item --image-size=@var{size}
38232 For the @code{image} action, create an image of the given @var{size}.
38233 @var{size} may be a number of bytes, or it may include a unit as a
38234 suffix (@pxref{Block size, size specifications,, coreutils, GNU
38237 When this option is omitted, @command{guix system} computes an estimate
38238 of the image size as a function of the size of the system declared in
38243 For the @code{container} action, allow containers to access the host network,
38244 that is, do not create a network namespace.
38246 @item --root=@var{file}
38247 @itemx -r @var{file}
38248 Make @var{file} a symlink to the result, and register it as a garbage
38251 @item --skip-checks
38252 Skip pre-installation safety checks.
38254 By default, @command{guix system init} and @command{guix system
38255 reconfigure} perform safety checks: they make sure the file systems that
38256 appear in the @code{operating-system} declaration actually exist
38257 (@pxref{File Systems}), and that any Linux kernel modules that may be
38258 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
38259 RAM Disk}). Passing this option skips these tests altogether.
38261 @item --allow-downgrades
38262 Instruct @command{guix system reconfigure} to allow system downgrades.
38264 By default, @command{reconfigure} prevents you from downgrading your
38265 system. It achieves that by comparing the provenance info of your
38266 system (shown by @command{guix system describe}) with that of your
38267 @command{guix} command (shown by @command{guix describe}). If the
38268 commits for @command{guix} are not descendants of those used for your
38269 system, @command{guix system reconfigure} errors out. Passing
38270 @option{--allow-downgrades} allows you to bypass these checks.
38273 Make sure you understand its security implications before using
38274 @option{--allow-downgrades}.
38278 @cindex on-error strategy
38279 @cindex error strategy
38280 @item --on-error=@var{strategy}
38281 Apply @var{strategy} when an error occurs when reading @var{file}.
38282 @var{strategy} may be one of the following:
38285 @item nothing-special
38286 Report the error concisely and exit. This is the default strategy.
38289 Likewise, but also display a backtrace.
38292 Report the error and enter Guile's debugger. From there, you can run
38293 commands such as @code{,bt} to get a backtrace, @code{,locals} to
38294 display local variable values, and more generally inspect the state of the
38295 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
38296 a list of available debugging commands.
38300 Once you have built, configured, re-configured, and re-re-configured
38301 your Guix installation, you may find it useful to list the operating
38302 system generations available on disk---and that you can choose from the
38303 bootloader boot menu:
38308 Describe the running system generation: its file name, the kernel and
38309 bootloader used, etc., as well as provenance information when available.
38311 The @code{--list-installed} flag is available, with the same
38312 syntax that is used in @command{guix package --list-installed}
38313 (@pxref{Invoking guix package}). When the flag is used,
38314 the description will include a list of packages that are currently
38315 installed in the system profile, with optional filtering based on a
38316 regular expression.
38319 The @emph{running} system generation---referred to by
38320 @file{/run/current-system}---is not necessarily the @emph{current}
38321 system generation---referred to by @file{/var/guix/profiles/system}: it
38322 differs when, for instance, you chose from the bootloader menu to boot
38323 an older generation.
38325 It can also differ from the @emph{booted} system generation---referred
38326 to by @file{/run/booted-system}---for instance because you reconfigured
38327 the system in the meantime.
38330 @item list-generations
38331 List a summary of each generation of the operating system available on
38332 disk, in a human-readable way. This is similar to the
38333 @option{--list-generations} option of @command{guix package}
38334 (@pxref{Invoking guix package}).
38336 Optionally, one can specify a pattern, with the same syntax that is used
38337 in @command{guix package --list-generations}, to restrict the list of
38338 generations displayed. For instance, the following command displays
38339 generations that are up to 10 days old:
38342 $ guix system list-generations 10d
38345 The @code{--list-installed} flag may also be specified, with the same
38346 syntax that is used in @command{guix package --list-installed}. This
38347 may be helpful if trying to determine when a package was added to the
38352 The @command{guix system} command has even more to offer! The following
38353 sub-commands allow you to visualize how your system services relate to
38356 @anchor{system-extension-graph}
38359 @item extension-graph
38360 Emit to standard output the @dfn{service
38361 extension graph} of the operating system defined in @var{file}
38362 (@pxref{Service Composition}, for more information on service
38363 extensions). By default the output is in Dot/Graphviz format, but you
38364 can choose a different format with @option{--graph-backend}, as with
38365 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
38370 $ guix system extension-graph @var{file} | xdot -
38373 shows the extension relations among services.
38376 The @command{dot} program is provided by the @code{graphviz} package.
38379 @anchor{system-shepherd-graph}
38380 @item shepherd-graph
38381 Emit to standard output the @dfn{dependency
38382 graph} of shepherd services of the operating system defined in
38383 @var{file}. @xref{Shepherd Services}, for more information and for an
38386 Again, the default output format is Dot/Graphviz, but you can pass
38387 @option{--graph-backend} to select a different one.
38391 @node Invoking guix deploy
38392 @section Invoking @code{guix deploy}
38394 We've already seen @code{operating-system} declarations used to manage a
38395 machine's configuration locally. Suppose you need to configure multiple
38396 machines, though---perhaps you're managing a service on the web that's
38397 comprised of several servers. @command{guix deploy} enables you to use those
38398 same @code{operating-system} declarations to manage multiple remote hosts at
38399 once as a logical ``deployment''.
38402 The functionality described in this section is still under development
38403 and is subject to change. Get in touch with us on
38404 @email{guix-devel@@gnu.org}!
38408 guix deploy @var{file}
38411 Such an invocation will deploy the machines that the code within @var{file}
38412 evaluates to. As an example, @var{file} might contain a definition like this:
38415 ;; This is a Guix deployment of a "bare bones" setup, with
38416 ;; no X11 display server, to a machine with an SSH daemon
38417 ;; listening on localhost:2222. A configuration such as this
38418 ;; may be appropriate for virtual machine with ports
38419 ;; forwarded to the host's loopback interface.
38421 (use-service-modules networking ssh)
38422 (use-package-modules bootloaders)
38426 (host-name "gnu-deployed")
38427 (timezone "Etc/UTC")
38428 (bootloader (bootloader-configuration
38429 (bootloader grub-bootloader)
38430 (targets '("/dev/vda"))
38431 (terminal-outputs '(console))))
38432 (file-systems (cons (file-system
38434 (device "/dev/vda1")
38436 %base-file-systems))
38438 (append (list (service dhcp-client-service-type)
38439 (service openssh-service-type
38440 (openssh-configuration
38441 (permit-root-login #t)
38442 (allow-empty-passwords? #t))))
38446 (operating-system %system)
38447 (environment managed-host-environment-type)
38448 (configuration (machine-ssh-configuration
38449 (host-name "localhost")
38450 (system "x86_64-linux")
38452 (identity "./id_rsa")
38456 The file should evaluate to a list of @var{machine} objects. This example,
38457 upon being deployed, will create a new generation on the remote system
38458 realizing the @code{operating-system} declaration @code{%system}.
38459 @code{environment} and @code{configuration} specify how the machine should be
38460 provisioned---that is, how the computing resources should be created and
38461 managed. The above example does not create any resources, as a
38462 @code{'managed-host} is a machine that is already running the Guix system and
38463 available over the network. This is a particularly simple case; a more
38464 complex deployment may involve, for example, starting virtual machines through
38465 a Virtual Private Server (VPS) provider. In such a case, a different
38466 @var{environment} type would be used.
38468 Do note that you first need to generate a key pair on the coordinator machine
38469 to allow the daemon to export signed archives of files from the store
38470 (@pxref{Invoking guix archive}), though this step is automatic on Guix
38474 # guix archive --generate-key
38478 Each target machine must authorize the key of the master machine so that it
38479 accepts store items it receives from the coordinator:
38482 # guix archive --authorize < coordinator-public-key.txt
38485 @code{user}, in this example, specifies the name of the user account to log in
38486 as to perform the deployment. Its default value is @code{root}, but root
38487 login over SSH may be forbidden in some cases. To work around this,
38488 @command{guix deploy} can log in as an unprivileged user and employ
38489 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
38490 currently installed on the remote and can be invoked non-interactively as
38491 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
38492 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
38493 be accomplished with the following operating system configuration snippet:
38497 (gnu system)) ;for %sudoers-specification
38499 (define %user "username")
38504 (plain-file "sudoers"
38505 (string-append (plain-file-content %sudoers-specification)
38506 (format #f "~a ALL = NOPASSWD: ALL~%"
38511 For more information regarding the format of the @file{sudoers} file,
38512 consult @command{man sudoers}.
38514 Once you've deployed a system on a set of machines, you may find it
38515 useful to run a command on all of them. The @option{--execute} or
38516 @option{-x} option lets you do that; the example below runs
38517 @command{uname -a} on all the machines listed in the deployment file:
38520 guix deploy @var{file} -x -- uname -a
38523 One thing you may often need to do after deployment is restart specific
38524 services on all the machines, which you can do like so:
38527 guix deploy @var{file} -x -- herd restart @var{service}
38530 The @command{guix deploy -x} command returns zero if and only if the
38531 command succeeded on all the machines.
38533 @c FIXME/TODO: Separate the API doc from the CLI doc.
38535 Below are the data types you need to know about when writing a
38538 @deftp {Data Type} machine
38539 This is the data type representing a single machine in a heterogeneous Guix
38543 @item @code{operating-system}
38544 The object of the operating system configuration to deploy.
38546 @item @code{environment}
38547 An @code{environment-type} describing how the machine should be provisioned.
38549 @item @code{configuration} (default: @code{#f})
38550 An object describing the configuration for the machine's @code{environment}.
38551 If the @code{environment} has a default configuration, @code{#f} may be used.
38552 If @code{#f} is used for an environment with no default configuration,
38553 however, an error will be thrown.
38557 @deftp {Data Type} machine-ssh-configuration
38558 This is the data type representing the SSH client parameters for a machine
38559 with an @code{environment} of @code{managed-host-environment-type}.
38562 @item @code{host-name}
38563 @item @code{build-locally?} (default: @code{#t})
38564 If false, system derivations will be built on the machine being deployed to.
38565 @item @code{system}
38566 The system type describing the architecture of the machine being deployed
38567 to---e.g., @code{"x86_64-linux"}.
38568 @item @code{authorize?} (default: @code{#t})
38569 If true, the coordinator's signing key will be added to the remote's ACL
38571 @item @code{port} (default: @code{22})
38572 @item @code{user} (default: @code{"root"})
38573 @item @code{identity} (default: @code{#f})
38574 If specified, the path to the SSH private key to use to authenticate with the
38577 @item @code{host-key} (default: @code{#f})
38578 This should be the SSH host key of the machine, which looks like this:
38581 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
38584 When @code{host-key} is @code{#f}, the server is authenticated against
38585 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
38588 @item @code{allow-downgrades?} (default: @code{#f})
38589 Whether to allow potential downgrades.
38591 Like @command{guix system reconfigure}, @command{guix deploy} compares
38592 the channel commits currently deployed on the remote host (as returned
38593 by @command{guix system describe}) to those currently in use (as
38594 returned by @command{guix describe}) to determine whether commits
38595 currently in use are descendants of those deployed. When this is not
38596 the case and @code{allow-downgrades?} is false, it raises an error.
38597 This ensures you do not accidentally downgrade remote machines.
38599 @item @code{safety-checks?} (default: @code{#t})
38600 Whether to perform ``safety checks'' before deployment. This includes
38601 verifying that devices and file systems referred to in the operating
38602 system configuration actually exist on the target machine, and making
38603 sure that Linux modules required to access storage devices at boot time
38604 are listed in the @code{initrd-modules} field of the operating system.
38606 These safety checks ensure that you do not inadvertently deploy a system
38607 that would fail to boot. Be careful before turning them off!
38611 @deftp {Data Type} digital-ocean-configuration
38612 This is the data type describing the Droplet that should be created for a
38613 machine with an @code{environment} of @code{digital-ocean-environment-type}.
38616 @item @code{ssh-key}
38617 The path to the SSH private key to use to authenticate with the remote
38618 host. In the future, this field may not exist.
38620 A list of string ``tags'' that uniquely identify the machine. Must be given
38621 such that no two machines in the deployment have the same set of tags.
38622 @item @code{region}
38623 A Digital Ocean region slug, such as @code{"nyc3"}.
38625 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
38626 @item @code{enable-ipv6?}
38627 Whether or not the droplet should be created with IPv6 networking.
38631 @node Running Guix in a VM
38632 @section Running Guix in a Virtual Machine
38634 @cindex virtual machine
38635 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM
38636 image distributed at
38637 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.qcow2}.
38638 This image is a compressed image in QCOW format. You can pass it to an
38639 emulator such as @uref{https://qemu.org/, QEMU} (see below for details).
38641 This image boots the Xfce graphical environment and it contains some
38642 commonly used tools. You can install more software in the image by running
38643 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
38644 also reconfigure the system based on its initial configuration file available
38645 as @file{/run/current-system/configuration.scm} (@pxref{Using the
38646 Configuration System}).
38648 Instead of using this pre-built image, one can also build their own
38649 image using @command{guix system image} (@pxref{Invoking guix system}).
38652 If you built your own image, you must copy it out of the store
38653 (@pxref{The Store}) and give yourself permission to write to the copy
38654 before you can use it. When invoking QEMU, you must choose a system
38655 emulator that is suitable for your hardware platform. Here is a minimal
38656 QEMU invocation that will boot the result of @command{guix system
38657 image -t qcow2} on x86_64 hardware:
38660 $ qemu-system-x86_64 \
38661 -nic user,model=virtio-net-pci \
38662 -enable-kvm -m 2048 \
38663 -device virtio-blk,drive=myhd \
38664 -drive if=none,file=/tmp/qemu-image,id=myhd
38667 Here is what each of these options means:
38670 @item qemu-system-x86_64
38671 This specifies the hardware platform to emulate. This should match the
38674 @item -nic user,model=virtio-net-pci
38675 Enable the unprivileged user-mode network stack. The guest OS can
38676 access the host but not vice versa. This is the simplest way to get the
38677 guest OS online. @code{model} specifies which network device to emulate:
38678 @code{virtio-net-pci} is a special device made for virtualized operating
38679 systems and recommended for most uses. Assuming your hardware platform is
38680 x86_64, you can get a list of available NIC models by running
38681 @command{qemu-system-x86_64 -nic model=help}.
38684 If your system has hardware virtualization extensions, enabling the
38685 virtual machine support (KVM) of the Linux kernel will make things run
38688 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
38690 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
38691 which may be insufficient for some operations.
38693 @item -device virtio-blk,drive=myhd
38694 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
38695 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
38696 better performance than if it were emulating a complete disk drive. See the
38697 QEMU and KVM documentation for more info.
38699 @item -drive if=none,file=/tmp/qemu-image,id=myhd
38700 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
38701 store of the ``myhd'' drive.
38704 The default @command{run-vm.sh} script that is returned by an invocation of
38705 @command{guix system vm} does not add a @command{-nic user} flag by default.
38706 To get network access from within the vm add the @code{(dhcp-client-service)}
38707 to your system definition and start the VM using
38708 @command{$(guix system vm config.scm) -nic user}. An important caveat of using
38709 @command{-nic user} for networking is that @command{ping} will not work, because
38710 it uses the ICMP protocol. You'll have to use a different command to check for
38711 network connectivity, for example @command{guix download}.
38713 @subsection Connecting Through SSH
38717 To enable SSH inside a VM you need to add an SSH server like
38718 @code{openssh-service-type} to your VM (@pxref{Networking Services,
38719 @code{openssh-service-type}}). In addition you need to forward the SSH port,
38720 22 by default, to the host. You can do this with
38723 $(guix system vm config.scm) -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
38726 To connect to the VM you can run
38729 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022 localhost
38732 The @command{-p} tells @command{ssh} the port you want to connect to.
38733 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
38734 every time you modify your @command{config.scm} file and the
38735 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
38736 connection to an unknown host every time you connect.
38739 If you find the above @samp{hostfwd} example not to be working (e.g.,
38740 your SSH client hangs attempting to connect to the mapped port of your
38741 VM), make sure that your Guix System VM has networking support, such as
38742 by using the @code{dhcp-client-service-type} service type.
38745 @subsection Using @command{virt-viewer} with Spice
38747 As an alternative to the default @command{qemu} graphical client you can
38748 use the @command{remote-viewer} from the @command{virt-viewer} package. To
38749 connect pass the @command{-spice port=5930,disable-ticketing} flag to
38750 @command{qemu}. See previous section for further information on how to do this.
38752 Spice also allows you to do some nice stuff like share your clipboard with your
38753 VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
38756 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
38757 -chardev spicevmc,name=vdagent,id=vdagent
38758 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,\
38759 name=com.redhat.spice.0
38762 You'll also need to add the @code{(spice-vdagent-service)} to your
38763 system definition (@pxref{Miscellaneous Services, Spice service}).
38765 @node Defining Services
38766 @section Defining Services
38768 The previous sections show the available services and how one can combine
38769 them in an @code{operating-system} declaration. But how do we define
38770 them in the first place? And what is a service anyway?
38773 * Service Composition:: The model for composing services.
38774 * Service Types and Services:: Types and services.
38775 * Service Reference:: API reference.
38776 * Shepherd Services:: A particular type of service.
38777 * Complex Configurations:: Defining bindings for complex configurations.
38780 @node Service Composition
38781 @subsection Service Composition
38785 Here we define a @dfn{service} as, broadly, something that extends the
38786 functionality of the operating system. Often a service is a process---a
38787 @dfn{daemon}---started when the system boots: a secure shell server, a
38788 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
38789 whose execution can be triggered by another daemon---e.g., an FTP server
38790 started by @command{inetd} or a D-Bus service activated by
38791 @command{dbus-daemon}. Occasionally, a service does not map to a
38792 daemon. For instance, the ``account'' service collects user accounts
38793 and makes sure they exist when the system runs; the ``udev'' service
38794 collects device management rules and makes them available to the eudev
38795 daemon; the @file{/etc} service populates the @file{/etc} directory
38798 @cindex service extensions
38799 Guix system services are connected by @dfn{extensions}. For instance, the
38800 secure shell service @emph{extends} the Shepherd---the
38801 initialization system, running as PID@tie{}1---by giving it the command
38802 lines to start and stop the secure shell daemon (@pxref{Networking
38803 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
38804 service by passing it its @file{.service} specification, and extends the
38805 udev service by passing it device management rules (@pxref{Desktop
38806 Services, @code{upower-service}}); the Guix daemon service extends the
38807 Shepherd by passing it the command lines to start and stop the daemon,
38808 and extends the account service by passing it a list of required build
38809 user accounts (@pxref{Base Services}).
38811 All in all, services and their ``extends'' relations form a directed
38812 acyclic graph (DAG). If we represent services as boxes and extensions
38813 as arrows, a typical system might provide something like this:
38815 @image{images/service-graph,,5in,Typical service extension graph.}
38817 @cindex system service
38818 At the bottom, we see the @dfn{system service}, which produces the
38819 directory containing everything to run and boot the system, as returned
38820 by the @command{guix system build} command. @xref{Service Reference},
38821 to learn about the other service types shown here.
38822 @xref{system-extension-graph, the @command{guix system extension-graph}
38823 command}, for information on how to generate this representation for a
38824 particular operating system definition.
38826 @cindex service types
38827 Technically, developers can define @dfn{service types} to express these
38828 relations. There can be any number of services of a given type on the
38829 system---for instance, a system running two instances of the GNU secure
38830 shell server (lsh) has two instances of @code{lsh-service-type}, with
38831 different parameters.
38833 The following section describes the programming interface for service
38834 types and services.
38836 @node Service Types and Services
38837 @subsection Service Types and Services
38839 A @dfn{service type} is a node in the DAG described above. Let us start
38840 with a simple example, the service type for the Guix build daemon
38841 (@pxref{Invoking guix-daemon}):
38844 (define guix-service-type
38848 (list (service-extension shepherd-root-service-type guix-shepherd-service)
38849 (service-extension account-service-type guix-accounts)
38850 (service-extension activation-service-type guix-activation)))
38851 (default-value (guix-configuration))))
38855 It defines three things:
38859 A name, whose sole purpose is to make inspection and debugging easier.
38862 A list of @dfn{service extensions}, where each extension designates the
38863 target service type and a procedure that, given the parameters of the
38864 service, returns a list of objects to extend the service of that type.
38866 Every service type has at least one service extension. The only
38867 exception is the @dfn{boot service type}, which is the ultimate service.
38870 Optionally, a default value for instances of this type.
38873 In this example, @code{guix-service-type} extends three services:
38876 @item shepherd-root-service-type
38877 The @code{guix-shepherd-service} procedure defines how the Shepherd
38878 service is extended. Namely, it returns a @code{<shepherd-service>}
38879 object that defines how @command{guix-daemon} is started and stopped
38880 (@pxref{Shepherd Services}).
38882 @item account-service-type
38883 This extension for this service is computed by @code{guix-accounts},
38884 which returns a list of @code{user-group} and @code{user-account}
38885 objects representing the build user accounts (@pxref{Invoking
38888 @item activation-service-type
38889 Here @code{guix-activation} is a procedure that returns a gexp, which is
38890 a code snippet to run at ``activation time''---e.g., when the service is
38894 A service of this type is instantiated like this:
38897 (service guix-service-type
38898 (guix-configuration
38900 (extra-options '("--gc-keep-derivations"))))
38903 The second argument to the @code{service} form is a value representing
38904 the parameters of this specific service instance.
38905 @xref{guix-configuration-type, @code{guix-configuration}}, for
38906 information about the @code{guix-configuration} data type. When the
38907 value is omitted, the default value specified by
38908 @code{guix-service-type} is used:
38911 (service guix-service-type)
38914 @code{guix-service-type} is quite simple because it extends other
38915 services but is not extensible itself.
38917 @c @subsubsubsection Extensible Service Types
38919 The service type for an @emph{extensible} service looks like this:
38922 (define udev-service-type
38923 (service-type (name 'udev)
38925 (list (service-extension shepherd-root-service-type
38926 udev-shepherd-service)))
38928 (compose concatenate) ;concatenate the list of rules
38929 (extend (lambda (config rules)
38931 (($ <udev-configuration> udev initial-rules)
38932 (udev-configuration
38933 (udev udev) ;the udev package to use
38934 (rules (append initial-rules rules)))))))))
38937 This is the service type for the
38938 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
38939 management daemon}. Compared to the previous example, in addition to an
38940 extension of @code{shepherd-root-service-type}, we see two new fields:
38944 This is the procedure to @dfn{compose} the list of extensions to
38945 services of this type.
38947 Services can extend the udev service by passing it lists of rules; we
38948 compose those extensions simply by concatenating them.
38951 This procedure defines how the value of the service is @dfn{extended} with
38952 the composition of the extensions.
38954 Udev extensions are composed into a list of rules, but the udev service
38955 value is itself a @code{<udev-configuration>} record. So here, we
38956 extend that record by appending the list of rules it contains to the
38957 list of contributed rules.
38960 This is a string giving an overview of the service type. The string can
38961 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
38962 @command{guix system search} command searches these strings and displays
38963 them (@pxref{Invoking guix system}).
38966 There can be only one instance of an extensible service type such as
38967 @code{udev-service-type}. If there were more, the
38968 @code{service-extension} specifications would be ambiguous.
38970 Still here? The next section provides a reference of the programming
38971 interface for services.
38973 @node Service Reference
38974 @subsection Service Reference
38976 We have seen an overview of service types (@pxref{Service Types and
38977 Services}). This section provides a reference on how to manipulate
38978 services and service types. This interface is provided by the
38979 @code{(gnu services)} module.
38981 @deffn {Scheme Procedure} service @var{type} [@var{value}]
38982 Return a new service of @var{type}, a @code{<service-type>} object (see
38983 below). @var{value} can be any object; it represents the parameters of
38984 this particular service instance.
38986 When @var{value} is omitted, the default value specified by @var{type}
38987 is used; if @var{type} does not specify a default value, an error is
38990 For instance, this:
38993 (service openssh-service-type)
38997 is equivalent to this:
39000 (service openssh-service-type
39001 (openssh-configuration))
39004 In both cases the result is an instance of @code{openssh-service-type}
39005 with the default configuration.
39008 @deffn {Scheme Procedure} service? @var{obj}
39009 Return true if @var{obj} is a service.
39012 @deffn {Scheme Procedure} service-kind @var{service}
39013 Return the type of @var{service}---i.e., a @code{<service-type>} object.
39016 @deffn {Scheme Procedure} service-value @var{service}
39017 Return the value associated with @var{service}. It represents its
39021 Here is an example of how a service is created and manipulated:
39025 (service nginx-service-type
39026 (nginx-configuration
39028 (log-directory log-directory)
39029 (run-directory run-directory)
39030 (file config-file))))
39035 (eq? (service-kind s) nginx-service-type)
39039 The @code{modify-services} form provides a handy way to change the
39040 parameters of some of the services of a list such as
39041 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
39042 evaluates to a list of services. Of course, you could always use
39043 standard list combinators such as @code{map} and @code{fold} to do that
39044 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
39045 @code{modify-services} simply provides a more concise form for this
39048 @deffn {Scheme Syntax} modify-services @var{services} @
39049 (@var{type} @var{variable} => @var{body}) @dots{}
39051 Modify the services listed in @var{services} according to the given
39052 clauses. Each clause has the form:
39055 (@var{type} @var{variable} => @var{body})
39058 where @var{type} is a service type---e.g.,
39059 @code{guix-service-type}---and @var{variable} is an identifier that is
39060 bound within the @var{body} to the service parameters---e.g., a
39061 @code{guix-configuration} instance---of the original service of that
39064 The @var{body} should evaluate to the new service parameters, which will
39065 be used to configure the new service. This new service will replace the
39066 original in the resulting list. Because a service's service parameters
39067 are created using @code{define-record-type*}, you can write a succinct
39068 @var{body} that evaluates to the new service parameters by using the
39069 @code{inherit} feature that @code{define-record-type*} provides.
39071 Clauses can also have the following form:
39074 (delete @var{type})
39077 Such a clause removes all services of the given @var{type} from
39080 @xref{Using the Configuration System}, for example usage.
39084 Next comes the programming interface for service types. This is
39085 something you want to know when writing new service definitions, but not
39086 necessarily when simply looking for ways to customize your
39087 @code{operating-system} declaration.
39089 @deftp {Data Type} service-type
39090 @cindex service type
39091 This is the representation of a @dfn{service type} (@pxref{Service Types
39096 This is a symbol, used only to simplify inspection and debugging.
39098 @item @code{extensions}
39099 A non-empty list of @code{<service-extension>} objects (see below).
39101 @item @code{compose} (default: @code{#f})
39102 If this is @code{#f}, then the service type denotes services that cannot
39103 be extended---i.e., services that do not receive ``values'' from other
39106 Otherwise, it must be a one-argument procedure. The procedure is called
39107 by @code{fold-services} and is passed a list of values collected from
39108 extensions. It may return any single value.
39110 @item @code{extend} (default: @code{#f})
39111 If this is @code{#f}, services of this type cannot be extended.
39113 Otherwise, it must be a two-argument procedure: @code{fold-services}
39114 calls it, passing it the initial value of the service as the first
39115 argument and the result of applying @code{compose} to the extension
39116 values as the second argument. It must return a value that is a valid
39117 parameter value for the service instance.
39119 @item @code{description}
39120 This is a string, possibly using Texinfo markup, describing in a couple
39121 of sentences what the service is about. This string allows users to
39122 find about the service through @command{guix system search}
39123 (@pxref{Invoking guix system}).
39125 @item @code{default-value} (default: @code{&no-default-value})
39126 The default value associated for instances of this service type. This
39127 allows users to use the @code{service} form without its second argument:
39130 (service @var{type})
39133 The returned service in this case has the default value specified by
39137 @xref{Service Types and Services}, for examples.
39140 @deffn {Scheme Procedure} service-extension @var{target-type} @
39142 Return a new extension for services of type @var{target-type}.
39143 @var{compute} must be a one-argument procedure: @code{fold-services}
39144 calls it, passing it the value associated with the service that provides
39145 the extension; it must return a valid value for the target service.
39148 @deffn {Scheme Procedure} service-extension? @var{obj}
39149 Return true if @var{obj} is a service extension.
39152 Occasionally, you might want to simply extend an existing service. This
39153 involves creating a new service type and specifying the extension of
39154 interest, which can be verbose; the @code{simple-service} procedure
39155 provides a shorthand for this.
39157 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
39158 Return a service that extends @var{target} with @var{value}. This works
39159 by creating a singleton service type @var{name}, of which the returned
39160 service is an instance.
39162 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
39166 (simple-service 'my-mcron-job mcron-service-type
39167 #~(job '(next-hour (3)) "guix gc -F 2G"))
39171 At the core of the service abstraction lies the @code{fold-services}
39172 procedure, which is responsible for ``compiling'' a list of services
39173 down to a single directory that contains everything needed to boot and
39174 run the system---the directory shown by the @command{guix system build}
39175 command (@pxref{Invoking guix system}). In essence, it propagates
39176 service extensions down the service graph, updating each node parameters
39177 on the way, until it reaches the root node.
39179 @deffn {Scheme Procedure} fold-services @var{services} @
39180 [#:target-type @var{system-service-type}]
39181 Fold @var{services} by propagating their extensions down to the root of
39182 type @var{target-type}; return the root service adjusted accordingly.
39185 Lastly, the @code{(gnu services)} module also defines several essential
39186 service types, some of which are listed below.
39188 @defvr {Scheme Variable} system-service-type
39189 This is the root of the service graph. It produces the system directory
39190 as returned by the @command{guix system build} command.
39193 @defvr {Scheme Variable} boot-service-type
39194 The type of the ``boot service'', which produces the @dfn{boot script}.
39195 The boot script is what the initial RAM disk runs when booting.
39198 @defvr {Scheme Variable} etc-service-type
39199 The type of the @file{/etc} service. This service is used to create
39200 files under @file{/etc} and can be extended by
39201 passing it name/file tuples such as:
39204 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
39207 In this example, the effect would be to add an @file{/etc/issue} file
39208 pointing to the given file.
39211 @defvr {Scheme Variable} setuid-program-service-type
39212 Type for the ``setuid-program service''. This service collects lists of
39213 executable file names, passed as gexps, and adds them to the set of
39214 setuid and setgid programs on the system (@pxref{Setuid Programs}).
39217 @defvr {Scheme Variable} profile-service-type
39218 Type of the service that populates the @dfn{system profile}---i.e., the
39219 programs under @file{/run/current-system/profile}. Other services can
39220 extend it by passing it lists of packages to add to the system profile.
39223 @cindex provenance tracking, of the operating system
39224 @anchor{provenance-service-type}
39225 @defvr {Scheme Variable} provenance-service-type
39226 This is the type of the service that records @dfn{provenance meta-data}
39227 in the system itself. It creates several files under
39228 @file{/run/current-system}:
39232 This is a ``channel file'' that can be passed to @command{guix pull -C}
39233 or @command{guix time-machine -C}, and which describes the channels used
39234 to build the system, if that information was available
39235 (@pxref{Channels}).
39237 @item configuration.scm
39238 This is the file that was passed as the value for this
39239 @code{provenance-service-type} service. By default, @command{guix
39240 system reconfigure} automatically passes the OS configuration file it
39241 received on the command line.
39244 This contains the same information as the two other files but in a
39245 format that is more readily processable.
39248 In general, these two pieces of information (channels and configuration
39249 file) are enough to reproduce the operating system ``from source''.
39252 This information is necessary to rebuild your operating system, but it
39253 is not always sufficient. In particular, @file{configuration.scm}
39254 itself is insufficient if it is not self-contained---if it refers to
39255 external Guile modules or to extra files. If you want
39256 @file{configuration.scm} to be self-contained, we recommend that modules
39257 or files it refers to be part of a channel.
39259 Besides, provenance meta-data is ``silent'' in the sense that it does
39260 not change the bits contained in your system, @emph{except for the
39261 meta-data bits themselves}. Two different OS configurations or sets of
39262 channels can lead to the same system, bit-for-bit; when
39263 @code{provenance-service-type} is used, these two systems will have
39264 different meta-data and thus different store file names, which makes
39265 comparison less trivial.
39268 This service is automatically added to your operating system
39269 configuration when you use @command{guix system reconfigure},
39270 @command{guix system init}, or @command{guix deploy}.
39273 @defvr {Scheme Variable} linux-loadable-module-service-type
39274 Type of the service that collects lists of packages containing
39275 kernel-loadable modules, and adds them to the set of kernel-loadable
39278 This service type is intended to be extended by other service types,
39282 (simple-service 'installing-module
39283 linux-loadable-module-service-type
39284 (list module-to-install-1
39285 module-to-install-2))
39288 This does not actually load modules at bootup, only adds it to the
39289 kernel profile so that it @emph{can} be loaded by other means.
39292 @node Shepherd Services
39293 @subsection Shepherd Services
39295 @cindex shepherd services
39297 @cindex init system
39298 The @code{(gnu services shepherd)} module provides a way to define
39299 services managed by the GNU@tie{}Shepherd, which is the
39300 initialization system---the first process that is started when the
39301 system boots, also known as PID@tie{}1
39302 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
39304 Services in the Shepherd can depend on each other. For instance, the
39305 SSH daemon may need to be started after the syslog daemon has been
39306 started, which in turn can only happen once all the file systems have
39307 been mounted. The simple operating system defined earlier (@pxref{Using
39308 the Configuration System}) results in a service graph like this:
39310 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
39312 You can actually generate such a graph for any operating system
39313 definition using the @command{guix system shepherd-graph} command
39314 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
39316 The @code{%shepherd-root-service} is a service object representing
39317 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
39318 by passing it lists of @code{<shepherd-service>} objects.
39320 @deftp {Data Type} shepherd-service
39321 The data type representing a service managed by the Shepherd.
39324 @item @code{provision}
39325 This is a list of symbols denoting what the service provides.
39327 These are the names that may be passed to @command{herd start},
39328 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
39329 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
39330 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
39332 @item @code{requirement} (default: @code{'()})
39333 List of symbols denoting the Shepherd services this one depends on.
39335 @cindex one-shot services, for the Shepherd
39336 @item @code{one-shot?} (default: @code{#f})
39337 Whether this service is @dfn{one-shot}. One-shot services stop immediately
39338 after their @code{start} action has completed. @xref{Slots of services,,,
39339 shepherd, The GNU Shepherd Manual}, for more info.
39341 @item @code{respawn?} (default: @code{#t})
39342 Whether to restart the service when it stops, for instance when the
39343 underlying process dies.
39346 @itemx @code{stop} (default: @code{#~(const #f)})
39347 The @code{start} and @code{stop} fields refer to the Shepherd's
39348 facilities to start and stop processes (@pxref{Service De- and
39349 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
39350 G-expressions that get expanded in the Shepherd configuration file
39351 (@pxref{G-Expressions}).
39353 @item @code{actions} (default: @code{'()})
39354 @cindex actions, of Shepherd services
39355 This is a list of @code{shepherd-action} objects (see below) defining
39356 @dfn{actions} supported by the service, in addition to the standard
39357 @code{start} and @code{stop} actions. Actions listed here become available as
39358 @command{herd} sub-commands:
39361 herd @var{action} @var{service} [@var{arguments}@dots{}]
39364 @item @code{auto-start?} (default: @code{#t})
39365 Whether this service should be started automatically by the Shepherd. If it
39366 is @code{#f} the service has to be started manually with @code{herd start}.
39368 @item @code{documentation}
39369 A documentation string, as shown when running:
39372 herd doc @var{service-name}
39375 where @var{service-name} is one of the symbols in @code{provision}
39376 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
39378 @item @code{modules} (default: @code{%default-modules})
39379 This is the list of modules that must be in scope when @code{start} and
39380 @code{stop} are evaluated.
39385 The example below defines a Shepherd service that spawns
39386 @command{syslogd}, the system logger from the GNU Networking Utilities
39387 (@pxref{syslogd invocation, @command{syslogd},, inetutils, GNU
39391 (let ((config (plain-file "syslogd.conf" "@dots{}")))
39393 (documentation "Run the syslog daemon (syslogd).")
39394 (provision '(syslogd))
39395 (requirement '(user-processes))
39396 (start #~(make-forkexec-constructor
39397 (list #$(file-append inetutils "/libexec/syslogd")
39398 "--rcfile" #$config)
39399 #:pid-file "/var/run/syslog.pid"))
39400 (stop #~(make-kill-destructor))))
39403 Key elements in this example are the @code{start} and @code{stop}
39404 fields: they are @dfn{staged} code snippets that use the
39405 @code{make-forkexec-constructor} procedure provided by the Shepherd and
39406 its dual, @code{make-kill-destructor} (@pxref{Service De- and
39407 Constructors,,, shepherd, The GNU Shepherd Manual}). The @code{start}
39408 field will have @command{shepherd} spawn @command{syslogd} with the
39409 given option; note that we pass @code{config} after @option{--rcfile},
39410 which is a configuration file declared above (contents of this file are
39411 omitted). Likewise, the @code{stop} field tells how this service is to
39412 be stopped; in this case, it is stopped by making the @code{kill} system
39413 call on its PID@. Code staging is achieved using G-expressions:
39414 @code{#~} stages code, while @code{#$} ``escapes'' back to host code
39415 (@pxref{G-Expressions}).
39417 @deftp {Data Type} shepherd-action
39418 This is the data type that defines additional actions implemented by a
39419 Shepherd service (see above).
39423 Symbol naming the action.
39425 @item documentation
39426 This is a documentation string for the action. It can be viewed by running:
39429 herd doc @var{service} action @var{action}
39433 This should be a gexp that evaluates to a procedure of at least one argument,
39434 which is the ``running value'' of the service (@pxref{Slots of services,,,
39435 shepherd, The GNU Shepherd Manual}).
39438 The following example defines an action called @code{say-hello} that kindly
39444 (documentation "Say hi!")
39445 (procedure #~(lambda (running . args)
39446 (format #t "Hello, friend! arguments: ~s\n"
39451 Assuming this action is added to the @code{example} service, then you can do:
39454 # herd say-hello example
39455 Hello, friend! arguments: ()
39456 # herd say-hello example a b c
39457 Hello, friend! arguments: ("a" "b" "c")
39460 This, as you can see, is a fairly sophisticated way to say hello.
39461 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
39465 @defvr {Scheme Variable} shepherd-root-service-type
39466 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
39468 This is the service type that extensions target when they want to create
39469 shepherd services (@pxref{Service Types and Services}, for an example).
39470 Each extension must pass a list of @code{<shepherd-service>}. Its
39471 value must be a @code{shepherd-configuration}, as described below.
39474 @deftp {Data Type} shepherd-configuration
39475 This data type represents the Shepherd's configuration.
39478 @item shepherd (default: @code{shepherd})
39479 The Shepherd package to use.
39481 @item services (default: @code{'()})
39482 A list of @code{<shepherd-service>} to start.
39483 You should probably use the service extension
39484 mechanism instead (@pxref{Shepherd Services}).
39488 The following example specifies the Shepherd package for the operating
39494 (services (append (list openssh-service-type))
39498 ;; Use own Shepherd package.
39499 (essential-services
39500 (modify-services (operating-system-default-essential-services
39501 this-operating-system)
39502 (shepherd-root-service-type config => (shepherd-configuration
39504 (shepherd my-shepherd))))))
39507 @defvr {Scheme Variable} %shepherd-root-service
39508 This service represents PID@tie{}1.
39511 @node Complex Configurations
39512 @subsection Complex Configurations
39513 @cindex complex configurations
39514 Some programs might have rather complex configuration files or formats,
39515 and to make it easier to create Scheme bindings for these configuration
39516 files, you can use the utilities defined in the @code{(gnu services
39517 configuration)} module.
39519 The main utility is the @code{define-configuration} macro, which you
39520 will use to define a Scheme record type (@pxref{Record Overview,,,
39521 guile, GNU Guile Reference Manual}). The Scheme record will be
39522 serialized to a configuration file by using @dfn{serializers}, which are
39523 procedures that take some kind of Scheme value and returns a
39524 G-expression (@pxref{G-Expressions}), which should, once serialized to
39525 the disk, return a string. More details are listed below.
39527 @deffn {Scheme Syntax} define-configuration @var{name} @var{clause1} @
39529 Create a record type named @code{@var{name}} that contains the
39530 fields found in the clauses.
39532 A clause can have one of the following forms:
39536 (@var{type} @var{default-value})
39537 @var{documentation})
39540 (@var{type} @var{default-value})
39541 @var{documentation}
39546 @var{documentation})
39550 @var{documentation}
39554 @var{field-name} is an identifier that denotes the name of the field in
39555 the generated record.
39557 @var{type} is the type of the value corresponding to @var{field-name};
39558 since Guile is untyped, a predicate
39559 procedure---@code{@var{type}?}---will be called on the value
39560 corresponding to the field to ensure that the value is of the correct
39561 type. This means that if say, @var{type} is @code{package}, then a
39562 procedure named @code{package?} will be applied on the value to make
39563 sure that it is indeed a @code{<package>} object.
39565 @var{default-value} is the default value corresponding to the field; if
39566 none is specified, the user is forced to provide a value when creating
39567 an object of the record type.
39569 @c XXX: Should these be full sentences or are they allow to be very
39570 @c short like package synopses?
39571 @var{documentation} is a string formatted with Texinfo syntax which
39572 should provide a description of what setting this field does.
39574 @var{serializer} is the name of a procedure which takes two arguments,
39575 the first is the name of the field, and the second is the value
39576 corresponding to the field. The procedure should return a string or
39577 G-expression (@pxref{G-Expressions}) that represents the content that
39578 will be serialized to the configuration file. If none is specified, a
39579 procedure of the name @code{serialize-@var{type}} will be used.
39581 A simple serializer procedure could look like this:
39584 (define (serialize-boolean field-name value)
39585 (let ((value (if value "true" "false")))
39586 #~(string-append #$field-name #$value)))
39589 In some cases multiple different configuration records might be defined
39590 in the same file, but their serializers for the same type might have to
39591 be different, because they have different configuration formats. For
39592 example, the @code{serialize-boolean} procedure for the Getmail service
39593 would have to be different from the one for the Transmission service. To
39594 make it easier to deal with this situation, one can specify a serializer
39595 prefix by using the @code{prefix} literal in the
39596 @code{define-configuration} form. This means that one doesn't have to
39597 manually specify a custom @var{serializer} for every field.
39600 (define (foo-serialize-string field-name value)
39603 (define (bar-serialize-string field-name value)
39606 (define-configuration foo-configuration
39609 "The name of label.")
39612 (define-configuration bar-configuration
39615 "The IPv4 address for this device.")
39619 However, in some cases you might not want to serialize any of the values
39620 of the record, to do this, you can use the @code{no-serialization}
39621 literal. There is also the @code{define-configuration/no-serialization}
39622 macro which is a shorthand of this.
39625 ;; Nothing will be serialized to disk.
39626 (define-configuration foo-configuration
39629 "Some documentation.")
39630 (no-serialization))
39632 ;; The same thing as above.
39633 (define-configuration/no-serialization bar-configuration
39636 "Some documentation."))
39640 @deffn {Scheme Syntax} define-maybe @var{type}
39641 Sometimes a field should not be serialized if the user doesn’t specify a
39642 value. To achieve this, you can use the @code{define-maybe} macro to
39643 define a ``maybe type''; if the value of a maybe type is left unset, or
39644 is set to the @code{%unset-value} value, then it will not be serialized.
39646 When defining a ``maybe type'', the corresponding serializer for the
39647 regular type will be used by default. For example, a field of type
39648 @code{maybe-string} will be serialized using the @code{serialize-string}
39649 procedure by default, you can of course change this by specifying a
39650 custom serializer procedure. Likewise, the type of the value would have
39651 to be a string, or left unspecified.
39654 (define-maybe string)
39656 (define (serialize-string field-name value)
39659 (define-configuration baz-configuration
39661 ;; If set to a string, the `serialize-string' procedure will be used
39662 ;; to serialize the string. Otherwise this field is not serialized.
39664 "The name of this module."))
39667 Like with @code{define-configuration}, one can set a prefix for the
39668 serializer name by using the @code{prefix} literal.
39671 (define-maybe integer
39674 (define (baz-serialize-integer field-name value)
39678 There is also the @code{no-serialization} literal, which when set means
39679 that no serializer will be defined for the ``maybe type'', regardless of
39680 whether its value is set or not.
39681 @code{define-maybe/no-serialization} is a shorthand for specifying the
39682 @code{no-serialization} literal.
39685 (define-maybe/no-serialization symbol)
39687 (define-configuration/no-serialization test-configuration
39694 @deffn (Scheme Procedure) maybe-value-set? @var{value}
39695 Predicate to check whether a user explicitly specified the value of a
39699 @deffn {Scheme Procedure} serialize-configuration @var{configuration} @
39701 Return a G-expression that contains the values corresponding to the
39702 @var{fields} of @var{configuration}, a record that has been generated by
39703 @code{define-configuration}. The G-expression can then be serialized to
39704 disk by using something like @code{mixed-text-file}.
39707 @deffn {Scheme Procedure} empty-serializer @var{field-name} @var{value}
39708 A serializer that just returns an empty string. The
39709 @code{serialize-package} procedure is an alias for this.
39712 Once you have defined a configuration record, you will most likely also
39713 want to document it so that other people know to use it. To help with
39714 that, there are two procedures, both of which are documented below.
39716 @deffn {Scheme Procedure} generate-documentation @var{documentation} @
39717 @var{documentation-name}
39718 Generate a Texinfo fragment from the docstrings in @var{documentation},
39719 a list of @code{(@var{label} @var{fields} @var{sub-documentation} ...)}.
39720 @var{label} should be a symbol and should be the name of the
39721 configuration record. @var{fields} should be a list of all the fields
39722 available for the configuration record.
39724 @var{sub-documentation} is a @code{(@var{field-name}
39725 @var{configuration-name})} tuple. @var{field-name} is the name of the
39726 field which takes another configuration record as its value, and
39727 @var{configuration-name} is the name of that configuration record.
39729 @var{sub-documentation} is only needed if there are nested configuration
39730 records. For example, the @code{getmail-configuration} record
39731 (@pxref{Mail Services}) accepts a @code{getmail-configuration-file}
39732 record in one of its @code{rcfile} field, therefore documentation for
39733 @code{getmail-configuration-file} is nested in
39734 @code{getmail-configuration}.
39737 (generate-documentation
39738 `((getmail-configuration ,getmail-configuration-fields
39739 (rcfile getmail-configuration-file))
39741 'getmail-configuration)
39744 @var{documentation-name} should be a symbol and should be the name of
39745 the configuration record.
39749 @deffn {Scheme Procedure} configuration->documentation
39750 @var{configuration-symbol}
39751 Take @var{configuration-symbol}, the symbol corresponding to the name
39752 used when defining a configuration record with
39753 @code{define-configuration}, and print the Texinfo documentation of its
39754 fields. This is useful if there aren’t any nested configuration records
39755 since it only prints the documentation for the top-level fields.
39758 As of right now, there is no automated way to generate documentation for
39759 configuration records and put them in the manual. Instead, every
39760 time you make a change to the docstrings of a configuration record, you
39761 have to manually call @code{generate-documentation} or
39762 @code{configuration->documentation}, and paste the output into the
39763 @file{doc/guix.texi} file.
39765 @c TODO: Actually test this
39766 Below is an example of a record type created using
39767 @code{define-configuration} and friends.
39770 (use-modules (gnu services)
39772 (gnu services configuration)
39776 ;; Turn field names, which are Scheme symbols into strings
39777 (define (uglify-field-name field-name)
39778 (let ((str (symbol->string field-name)))
39779 ;; field? -> is-field
39780 (if (string-suffix? "?" str)
39781 (string-append "is-" (string-drop-right str 1))
39784 (define (serialize-string field-name value)
39785 #~(string-append #$(uglify-field-name field-name) " = " #$value "\n"))
39787 (define (serialize-integer field-name value)
39788 (serialize-string field-name (number->string value)))
39790 (define (serialize-boolean field-name value)
39791 (serialize-string field-name (if value "true" "false")))
39793 (define (serialize-contact-name field-name value)
39794 #~(string-append "\n[" #$value "]\n"))
39796 (define (list-of-contact-configurations? lst)
39797 (every contact-configuration? lst))
39799 (define (serialize-list-of-contact-configurations field-name value)
39800 #~(string-append #$@@(map (cut serialize-configuration <>
39801 contact-configuration-fields)
39804 (define (serialize-contacts-list-configuration configuration)
39807 #~(string-append "[Owner]\n"
39808 #$(serialize-configuration
39809 configuration contacts-list-configuration-fields))))
39811 (define-maybe integer)
39812 (define-maybe string)
39814 (define-configuration contact-configuration
39817 "The name of the contact."
39818 serialize-contact-name)
39821 "The person's phone number.")
39824 "The person's email address.")
39827 "Whether the person is married."))
39829 (define-configuration contacts-list-configuration
39832 "The name of the owner of this contact list.")
39835 "The owner's email address.")
39837 (list-of-contact-configurations '())
39838 "A list of @@code@{contact-configuation@} records which contain
39839 information about all your contacts."))
39842 A contacts list configuration could then be created like this:
39845 (define my-contacts
39846 (contacts-list-configuration
39848 (email "alice@@example.org")
39850 (list (contact-configuration
39852 (phone-number 1234)
39853 (email "bob@@gnu.org")
39855 (contact-configuration
39857 (phone-number 0000)
39861 After serializing the configuration to disk, the resulting file would
39867 email = alice@@example.org
39870 phone-number = 1234
39871 email = bob@@gnu.org
39880 @node Home Configuration
39881 @chapter Home Configuration
39882 @cindex home configuration
39883 Guix supports declarative configuration of @dfn{home environments} by
39884 utilizing the configuration mechanism described in the previous chapter
39885 (@pxref{Defining Services}), but for user's dotfiles and packages. It
39886 works both on Guix System and foreign distros and allows users to
39887 declare all the packages and services that should be installed and
39888 configured for the user. Once a user has written a file containing
39889 @code{home-environment} record, such a configuration can be
39890 @dfn{instantiated} by an unprivileged user with the @command{guix home}
39891 command (@pxref{Invoking guix home}).
39892 @c Maybe later, it will be possible to make home configuration a part of
39893 @c system configuration to make everything managed by guix system.
39896 The functionality described in this section is still under development
39897 and is subject to change. Get in touch with us on
39898 @email{guix-devel@@gnu.org}!
39901 The user's home environment usually consists of three basic parts:
39902 software, configuration, and state. Software in mainstream distros are
39903 usually installed system-wide, but with GNU Guix most software packages
39904 can be installed on a per-user basis without needing root privileges,
39905 and are thus considered part of the user’s @dfn{home environment}.
39906 Packages on their own are not very useful in many cases, because often they
39907 require some additional configuration, usually config files that reside
39908 in @env{XDG_CONFIG_HOME} (@file{~/.config} by default) or other
39909 directories. Everything else can be considered state, like media files,
39910 application databases, and logs.
39912 Using Guix for managing home environments provides a number of
39917 @item All software can be configured in one language (Guile Scheme),
39918 this gives users the ability to share values between configurations of
39919 different programs.
39921 @item A well-defined home environment is self-contained and can be
39922 created in a declarative and reproducible way---there is no need to grab
39923 external binaries or manually edit some configuration file.
39925 @item After every @command{guix home reconfigure} invocation, a new home
39926 environment generation will be created. This means that users can
39927 rollback to a previous home environment generation so they don’t have to
39928 worry about breaking their configuration.
39930 @item It is possible to manage stateful data with Guix Home, this
39931 includes the ability to automatically clone Git repositories on the
39932 initial setup of the machine, and periodically running commands like
39933 @command{rsync} to sync data with another host. This functionality is
39934 still in an experimental stage, though.
39939 * Declaring the Home Environment:: Customizing your Home.
39940 * Configuring the Shell:: Enabling home environment.
39941 * Home Services:: Specifying home services.
39942 * Invoking guix home:: Instantiating a home configuration.
39945 @node Declaring the Home Environment
39946 @section Declaring the Home Environment
39947 The home environment is configured by providing a
39948 @code{home-environment} declaration in a file that can be passed to the
39949 @command{guix home} command (@pxref{Invoking guix home}). The easiest
39950 way to get started is by generating an initial configuration with
39951 @command{guix home import}:
39954 guix home import ~/src/guix-config
39957 The @command{guix home import} command reads some of the ``dot files''
39958 such as @file{~/.bashrc} found in your home directory and copies them to
39959 the given directory, @file{~/src/guix-config} in this case; it also
39960 reads the contents of your profile, @file{~/.guix-profile}, and, based
39961 on that, it populates @file{~/src/guix-config/home-configuration.scm}
39962 with a Home configuration that resembles your current configuration.
39964 A simple setup can include Bash and a custom text configuration, like in
39965 the example below. Don't be afraid to declare home environment parts,
39966 which overlaps with your current dot files: before installing any
39967 configuration files, Guix Home will back up existing config files to a
39968 separate place in the home directory.
39971 It is highly recommended that you manage your shell or shells with Guix
39972 Home, because it will make sure that all the necessary scripts are
39973 sourced by the shell configuration file. Otherwise you will need to do
39974 it manually. (@pxref{Configuring the Shell}).
39977 @findex home-environment
39979 @include he-config-bare-bones.scm
39982 The @code{packages} field should be self-explanatory, it will install
39983 the list of packages into the user's profile. The most important field
39984 is @code{services}, it contains a list of @dfn{home services}, which are
39985 the basic building blocks of a home environment.
39987 There is no daemon (at least not necessarily) related to a home service,
39988 a home service is just an element that is used to declare part of home
39989 environment and extend other parts of it. The extension mechanism
39990 discussed in the previous chapter (@pxref{Defining Services}) should not
39991 be confused with Shepherd services (@pxref{Shepherd Services}). Using this extension
39992 mechanism and some Scheme code that glues things together gives the user
39993 the freedom to declare their own, very custom, home environments.
39995 @cindex container, for @command{guix home}
39996 Once the configuration looks good, you can first test it in a throw-away
40000 guix home container config.scm
40003 The command above spawns a shell where your home environment is running.
40004 The shell runs in a container, meaning it's isolated from the rest of
40005 the system, so it's a good way to try out your configuration---you can
40006 see if configuration bits are missing or misbehaving, if daemons get
40007 started, and so on. Once you exit that shell, you're back to the prompt
40008 of your original shell ``in the real world''.
40010 Once you have a configuration file that suits your needs, you can
40011 reconfigure your home by running:
40014 guix home reconfigure config.scm
40017 This ``builds'' your home environment and creates @file{~/.guix-home}
40018 pointing to it. Voilà!
40021 Make sure the operating system has elogind, systemd, or a similar
40022 mechanism to create the XDG run-time directory and has the
40023 @env{XDG_RUNTIME_DIR} variable set. Failing that, the
40024 @file{on-first-login} script will not execute anything, and processes
40025 like user Shepherd and its descendants will not start.
40028 @node Configuring the Shell
40029 @section Configuring the Shell
40030 This section is safe to skip if your shell or shells are managed by
40031 Guix Home. Otherwise, read it carefully.
40033 There are a few scripts that must be evaluated by a login shell to
40034 activate the home environment. The shell startup files only read by
40035 login shells often have @code{profile} suffix. For more information
40036 about login shells see @ref{Invoking Bash,,, bash, The GNU Bash
40037 Reference Manual} and see @ref{Bash Startup Files,,, bash, The GNU Bash
40040 The first script that needs to be sourced is @file{setup-environment},
40041 which sets all the necessary environment variables (including variables
40042 declared by the user) and the second one is @file{on-first-login}, which
40043 starts Shepherd for the current user and performs actions declared by
40044 other home services that extends
40045 @code{home-run-on-first-login-service-type}.
40047 Guix Home will always create @file{~/.profile}, which contains the
40051 HOME_ENVIRONMENT=$HOME/.guix-home
40052 . $HOME_ENVIRONMENT/setup-environment
40053 $HOME_ENVIRONMENT/on-first-login
40056 This makes POSIX compliant login shells activate the home environment.
40057 However, in most cases this file won't be read by most modern shells,
40058 because they are run in non POSIX mode by default and have their own
40059 @file{*profile} startup files. For example Bash will prefer
40060 @file{~/.bash_profile} in case it exists and only if it doesn't will it
40061 fallback to @file{~/.profile}. Zsh (if no additional options are
40062 specified) will ignore @file{~/.profile}, even if @file{~/.zprofile}
40065 To make your shell respect @file{~/.profile}, add @code{. ~/.profile} or
40066 @code{source ~/.profile} to the startup file for the login shell. In
40067 case of Bash, it is @file{~/.bash_profile}, and in case of Zsh, it is
40068 @file{~/.zprofile}.
40071 This step is only required if your shell is @emph{not} managed by Guix Home.
40072 Otherwise, everything will be done automatically.
40075 @node Home Services
40076 @section Home Services
40077 @cindex home services
40079 A @dfn{home service} is not necessarily something that has a daemon and
40080 is managed by Shepherd (@pxref{Jump Start,,, shepherd, The GNU Shepherd
40081 Manual}), in most cases it doesn't. It's a simple building block of the
40082 home environment, often declaring a set of packages to be installed in
40083 the home environment profile, a set of config files to be symlinked into
40084 @env{XDG_CONFIG_HOME} (@file{~/.config} by default), and environment
40085 variables to be set by a login shell.
40087 There is a service extension mechanism (@pxref{Service Composition})
40088 which allows home services to extend other home services and utilize
40089 capabilities they provide; for example: declare mcron jobs
40090 (@pxref{Top,,, mcron, GNU@tie{}Mcron}) by extending @ref{Mcron Home
40091 Service}; declare daemons by extending @ref{Shepherd Home Service}; add
40092 commands, which will be invoked on by the Bash by extending
40093 @ref{Shells Home Services, @code{home-bash-service-type}}.
40095 A good way to discover available home services is using the
40096 @command{guix home search} command (@pxref{Invoking guix home}). After
40097 the required home services are found, include its module with the
40098 @code{use-modules} form (@pxref{use-modules,, Using Guile Modules,
40099 guile, The GNU Guile Reference Manual}), or the @code{#:use-modules}
40100 directive (@pxref{define-module,, Creating Guile Modules, guile, The GNU
40101 Guile Reference Manual}) and declare a home service using the
40102 @code{service} function, or extend a service type by declaring a new
40103 service with the @code{simple-service} procedure from @code{(gnu
40107 * Essential Home Services:: Environment variables, packages, on-* scripts.
40108 * Shells: Shells Home Services. POSIX shells, Bash, Zsh.
40109 * Mcron: Mcron Home Service. Scheduled User's Job Execution.
40110 * Shepherd: Shepherd Home Service. Managing User's Daemons.
40111 * SSH: Secure Shell. Setting up the secure shell client.
40112 * Desktop: Desktop Home Services. Services for graphical environments.
40113 * Guix: Guix Home Services. Services for Guix.
40115 @c In addition to that Home Services can provide
40117 @node Essential Home Services
40118 @subsection Essential Home Services
40119 There are a few essential home services defined in
40120 @code{(gnu services)}, they are mostly for internal use and are required
40121 to build a home environment, but some of them will be useful for the end
40124 @cindex environment variables
40126 @defvr {Scheme Variable} home-environment-variables-service-type
40127 The service of this type will be instantiated by every home environment
40128 automatically by default, there is no need to define it, but someone may
40129 want to extend it with a list of pairs to set some environment
40133 (list ("ENV_VAR1" . "value1")
40134 ("ENV_VAR2" . "value2"))
40137 The easiest way to extend a service type, without defining a new service
40138 type is to use the @code{simple-service} helper from @code{(gnu
40142 (simple-service 'some-useful-env-vars-service
40143 home-environment-variables-service-type
40144 `(("LESSHISTFILE" . "$XDG_CACHE_HOME/.lesshst")
40145 ("SHELL" . ,(file-append zsh "/bin/zsh"))
40146 ("USELESS_VAR" . #f)
40147 ("_JAVA_AWT_WM_NONREPARENTING" . #t)))
40150 If you include such a service in you home environment definition, it
40151 will add the following content to the @file{setup-environment} script
40152 (which is expected to be sourced by the login shell):
40155 export LESSHISTFILE=$XDG_CACHE_HOME/.lesshst
40156 export SHELL=/gnu/store/2hsg15n644f0glrcbkb1kqknmmqdar03-zsh-5.8/bin/zsh
40157 export _JAVA_AWT_WM_NONREPARENTING
40161 Make sure that module @code{(gnu packages shells)} is imported with
40162 @code{use-modules} or any other way, this namespace contains the
40163 definition of the @code{zsh} package, which is used in the example
40167 The association list (@pxref{Association Lists, alists, Association
40168 Lists, guile, The GNU Guile Reference manual}) is a data structure
40169 containing key-value pairs, for
40170 @code{home-environment-variables-service-type} the key is always a
40171 string, the value can be a string, string-valued gexp
40172 (@pxref{G-Expressions}), file-like object (@pxref{G-Expressions,
40173 file-like object}) or boolean. For gexps, the variable will be set to
40174 the value of the gexp; for file-like objects, it will be set to the path
40175 of the file in the store (@pxref{The Store}); for @code{#t}, it will
40176 export the variable without any value; and for @code{#f}, it will omit
40181 @defvr {Scheme Variable} home-profile-service-type
40182 The service of this type will be instantiated by every home environment
40183 automatically, there is no need to define it, but you may want to extend
40184 it with a list of packages if you want to install additional packages
40185 into your profile. Other services, which need to make some programs
40186 available to the user will also extend this service type.
40188 The extension value is just a list of packages:
40191 (list htop vim emacs)
40194 The same approach as @code{simple-service} (@pxref{Service Reference,
40195 simple-service}) for @code{home-environment-variables-service-type} can
40196 be used here, too. Make sure that modules containing the specified
40197 packages are imported with @code{use-modules}. To find a package or
40198 information about its module use @command{guix search} (@pxref{Invoking
40199 guix package}). Alternatively, @code{specification->package} can be
40200 used to get the package record from string without importing related
40204 There are few more essential services, but users are not expected to
40207 @defvr {Scheme Variable} home-service-type
40208 The root of home services DAG, it generates a folder, which later will be
40209 symlinked to @file{~/.guix-home}, it contains configurations,
40210 profile with binaries and libraries, and some necessary scripts to glue
40214 @defvr {Scheme Variable} home-run-on-first-login-service-type
40215 The service of this type generates a Guile script, which is expected to
40216 be executed by the login shell. It is only executed if the special flag
40217 file inside @env{XDG_RUNTIME_DIR} hasn't been created, this prevents
40218 redundant executions of the script if multiple login shells are spawned.
40220 It can be extended with a gexp. However, to autostart an application,
40221 users @emph{should not} use this service, in most cases it's better to extend
40222 @code{home-shepherd-service-type} with a Shepherd service
40223 (@pxref{Shepherd Services}), or extend the shell's startup file with
40224 the required command using the appropriate service type.
40227 @defvr {Scheme Variable} home-files-service-type
40228 The service of this type allows to specify a list of files, which will
40229 go to @file{~/.guix-home/files}, usually this directory contains
40230 configuration files (to be more precise it contains symlinks to files in
40231 @file{/gnu/store}), which should be placed in @file{$XDG_CONFIG_DIR} or
40232 in rare cases in @file{$HOME}. It accepts extension values in the
40236 `((".sway/config" ,sway-file-like-object)
40237 (".tmux.conf" ,(local-file "./tmux.conf")))
40240 Each nested list contains two values: a subdirectory and file-like
40241 object. After building a home environment @file{~/.guix-home/files}
40242 will be populated with apropiate content and all nested directories will
40243 be created accordingly, however, those files won't go any further until
40244 some other service will do it. By default a
40245 @code{home-symlink-manager-service-type}, which creates necessary
40246 symlinks in home folder to files from @file{~/.guix-home/files} and
40247 backs up already existing, but clashing configs and other things, is a
40248 part of essential home services (enabled by default), but it's possible
40249 to use alternative services to implement more advanced use cases like
40250 read-only home. Feel free to experiment and share your results.
40253 @defvr {Scheme Variable} home-xdg-configuration-files-service-type
40254 The service is very similiar to @code{home-files-service-type} (and
40255 actually extends it), but used for defining files, which will go to
40256 @file{~/.guix-home/files/.config}, which will be symlinked to
40257 @file{$XDG_CONFIG_DIR} by @code{home-symlink-manager-service-type} (for
40258 example) during activation. It accepts extension values in the
40262 `(("sway/config" ,sway-file-like-object)
40263 ;; -> ~/.guix-home/files/.config/sway/config
40264 ;; -> $XDG_CONFIG_DIR/sway/config (by symlink-manager)
40265 ("tmux/tmux.conf" ,(local-file "./tmux.conf")))
40269 @defvr {Scheme Variable} home-activation-service-type
40270 The service of this type generates a guile script, which runs on every
40271 @command{guix home reconfigure} invocation or any other action, which
40272 leads to the activation of the home environment.
40275 @defvr {Scheme Variable} home-symlink-manager-service-type
40276 The service of this type generates a guile script, which will be
40277 executed during activation of home environment, and do a few following
40282 Reads the content of @file{files/} directory of current and pending home
40286 Cleans up all symlinks created by symlink-manager on previous
40287 activation. Also, sub-directories, which become empty also will be
40291 Creates new symlinks the following way: It looks @file{files/} directory
40292 (usually defined with @code{home-files-service-type},
40293 @code{home-xdg-configuration-files-service-type} and maybe some others),
40294 takes the files from @file{files/.config/} subdirectory and put
40295 respective links in @env{XDG_CONFIG_DIR}. For example symlink for
40296 @file{files/.config/sway/config} will end up in
40297 @file{$XDG_CONFIG_DIR/sway/config}. The rest files in @file{files/}
40298 outside of @file{files/.config/} subdirectory will be treated slightly
40299 different: symlink will just go to @file{$HOME}.
40300 @file{files/.some-program/config} will end up in
40301 @file{$HOME/.some-program/config}.
40304 If some sub-directories are missing, they will be created.
40307 If there is a clashing files on the way, they will be backed up.
40311 symlink-manager is a part of essential home services and is enabled and
40316 @node Shells Home Services
40320 @cindex login shell
40321 @cindex interactive shell
40325 Shells play a quite important role in the environment initialization
40326 process, you can configure them manually as described in section
40327 @ref{Configuring the Shell}, but the recommended way is to use home services
40328 listed below. It's both easier and more reliable.
40330 Each home environment instantiates
40331 @code{home-shell-profile-service-type}, which creates a
40332 @file{~/.profile} startup file for all POSIX-compatible shells. This
40333 file contains all the necessary steps to properly initialize the
40334 environment, but many modern shells like Bash or Zsh prefer their own
40335 startup files, that's why the respective home services
40336 (@code{home-bash-service-type} and @code{home-zsh-service-type}) ensure
40337 that @file{~/.profile} is sourced by @file{~/.bash_profile} and
40338 @file{~/.zprofile}, respectively.
40340 @subsubheading Shell Profile Service
40342 @deftp {Data Type} home-shell-profile-configuration
40343 Available @code{home-shell-profile-configuration} fields are:
40346 @item @code{profile} (default: @code{()}) (type: text-config)
40347 @code{home-shell-profile} is instantiated automatically by
40348 @code{home-environment}, DO NOT create this service manually, it can
40349 only be extended. @code{profile} is a list of file-like objects, which
40350 will go to @file{~/.profile}. By default @file{~/.profile} contains the
40351 initialization code which must be evaluated by the login shell to make
40352 home-environment's profile available to the user, but other commands can
40353 be added to the file if it is really necessary. In most cases shell's
40354 configuration files are preferred places for user's customizations.
40355 Extend home-shell-profile service only if you really know what you do.
40361 @subsubheading Bash Home Service
40363 @anchor{home-bash-configuration}
40364 @deftp {Data Type} home-bash-configuration
40365 Available @code{home-bash-configuration} fields are:
40368 @item @code{package} (default: @code{bash}) (type: package)
40369 The Bash package to use.
40371 @item @code{guix-defaults?} (default: @code{#t}) (type: boolean)
40372 Add sane defaults like reading @file{/etc/bashrc} and coloring the output of
40373 @command{ls} to the top of the @file{.bashrc} file.
40375 @item @code{environment-variables} (default: @code{()}) (type: alist)
40376 Association list of environment variables to set for the Bash session. The
40377 rules for the @code{home-environment-variables-service-type} apply
40378 here (@pxref{Essential Home Services}). The contents of this field will be
40379 added after the contents of the @code{bash-profile} field.
40381 @item @code{aliases} (default: @code{()}) (type: alist)
40382 Association list of aliases to set for the Bash session. The aliases
40383 will be defined after the contents of the @code{bashrc} field has been
40384 put in the @file{.bashrc} file. The alias will automatically be quoted,
40385 so something like this:
40388 '(("ls" . "ls -alF"))
40397 @item @code{bash-profile} (default: @code{()}) (type: text-config)
40398 List of file-like objects, which will be added to @file{.bash_profile}.
40399 Used for executing user's commands at start of login shell (In most
40400 cases the shell started on tty just after login). @file{.bash_login}
40401 won't be ever read, because @file{.bash_profile} always present.
40403 @item @code{bashrc} (default: @code{()}) (type: text-config)
40404 List of file-like objects, which will be added to @file{.bashrc}. Used
40405 for executing user's commands at start of interactive shell (The shell
40406 for interactive usage started by typing @code{bash} or by terminal app
40407 or any other program).
40409 @item @code{bash-logout} (default: @code{()}) (type: text-config)
40410 List of file-like objects, which will be added to @file{.bash_logout}.
40411 Used for executing user's commands at the exit of login shell. It won't
40412 be read in some cases (if the shell terminates by exec'ing another
40413 process for example).
40418 You can extend the Bash service by using the @code{home-bash-extension}
40419 configuration record, whose fields must mirror that of
40420 @code{home-bash-configuration} (@pxref{home-bash-configuration}). The
40421 contents of the extensions will be added to the end of the corresponding
40422 Bash configuration files (@pxref{Bash Startup Files,,, bash, The GNU
40423 Bash Reference Manual}.
40425 For example, here is how you would define a service that extends the
40426 Bash service such that @file{~/.bash_profile} defines an additional
40427 environment variable, @env{PS1}:
40430 (define bash-fancy-prompt-service
40431 (simple-service 'bash-fancy-prompt
40432 home-bash-service-type
40433 (home-bash-extension
40434 (environment-variables
40435 '(("PS1" . "\\u \\wλ "))))))
40438 You would then add @code{bash-fancy-prompt-service} to the list in the
40439 @code{services} field of your @code{home-environment}. The reference of
40440 @code{home-bash-extension} follows.
40442 @deftp {Data Type} home-bash-extension
40443 Available @code{home-bash-extension} fields are:
40446 @item @code{environment-variables} (default: @code{()}) (type: alist)
40447 Additional environment variables to set. These will be combined with the
40448 environment variables from other extensions and the base service to form one
40449 coherent block of environment variables.
40451 @item @code{aliases} (default: @code{()}) (type: alist)
40452 Additional aliases to set. These will be combined with the aliases from
40453 other extensions and the base service.
40455 @item @code{bash-profile} (default: @code{()}) (type: text-config)
40456 Additional text blocks to add to @file{.bash_profile}, which will be combined
40457 with text blocks from other extensions and the base service.
40459 @item @code{bashrc} (default: @code{()}) (type: text-config)
40460 Additional text blocks to add to @file{.bashrc}, which will be combined
40461 with text blocks from other extensions and the base service.
40463 @item @code{bash-logout} (default: @code{()}) (type: text-config)
40464 Additional text blocks to add to @file{.bash_logout}, which will be combined
40465 with text blocks from other extensions and the base service.
40470 @subsubheading Zsh Home Service
40472 @deftp {Data Type} home-zsh-configuration
40473 Available @code{home-zsh-configuration} fields are:
40476 @item @code{package} (default: @code{zsh}) (type: package)
40477 The Zsh package to use.
40479 @item @code{xdg-flavor?} (default: @code{#t}) (type: boolean)
40480 Place all the configs to @file{$XDG_CONFIG_HOME/zsh}. Makes
40481 @file{~/.zshenv} to set @env{ZDOTDIR} to @file{$XDG_CONFIG_HOME/zsh}.
40482 Shell startup process will continue with
40483 @file{$XDG_CONFIG_HOME/zsh/.zshenv}.
40485 @item @code{environment-variables} (default: @code{()}) (type: alist)
40486 Association list of environment variables to set for the Zsh session.
40488 @item @code{zshenv} (default: @code{()}) (type: text-config)
40489 List of file-like objects, which will be added to @file{.zshenv}. Used
40490 for setting user's shell environment variables. Must not contain
40491 commands assuming the presence of tty or producing output. Will be read
40492 always. Will be read before any other file in @env{ZDOTDIR}.
40494 @item @code{zprofile} (default: @code{()}) (type: text-config)
40495 List of file-like objects, which will be added to @file{.zprofile}. Used
40496 for executing user's commands at start of login shell (In most cases the
40497 shell started on tty just after login). Will be read before
40500 @item @code{zshrc} (default: @code{()}) (type: text-config)
40501 List of file-like objects, which will be added to @file{.zshrc}. Used
40502 for executing user's commands at start of interactive shell (The shell
40503 for interactive usage started by typing @code{zsh} or by terminal app or
40504 any other program).
40506 @item @code{zlogin} (default: @code{()}) (type: text-config)
40507 List of file-like objects, which will be added to @file{.zlogin}. Used
40508 for executing user's commands at the end of starting process of login
40511 @item @code{zlogout} (default: @code{()}) (type: text-config)
40512 List of file-like objects, which will be added to @file{.zlogout}. Used
40513 for executing user's commands at the exit of login shell. It won't be
40514 read in some cases (if the shell terminates by exec'ing another process
40521 @node Mcron Home Service
40522 @subsection Scheduled User's Job Execution
40526 @cindex scheduling jobs
40528 The @code{(gnu home services mcron)} module provides an interface to
40529 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
40530 mcron, GNU@tie{}mcron}). The information about system's mcron is
40531 applicable here (@pxref{Scheduled Job Execution}), the only difference
40532 for home services is that they have to be declared in a
40533 @code{home-environment} record instead of an @code{operating-system}
40536 @defvr {Scheme Variable} home-mcron-service-type
40537 This is the type of the @code{mcron} home service, whose value is an
40538 @code{home-mcron-configuration} object. It allows to manage scheduled
40541 This service type can be the target of a service extension that provides
40542 additional job specifications (@pxref{Service Composition}). In other
40543 words, it is possible to define services that provide additional mcron
40547 @deftp {Data Type} home-mcron-configuration
40548 Data type representing the configuration of mcron.
40551 @item @code{mcron} (default: @var{mcron})
40552 The mcron package to use.
40555 This is a list of gexps (@pxref{G-Expressions}), where each gexp
40556 corresponds to an mcron job specification (@pxref{Syntax, mcron job
40557 specifications,, mcron, GNU@tie{}mcron}).
40561 @node Shepherd Home Service
40562 @subsection Managing User Daemons
40564 @cindex shepherd services, for users
40565 The @code{(gnu home services shepherd)} module supports the definitions
40566 of per-user Shepherd services (@pxref{Introduction,,, shepherd, The GNU
40567 Shepherd Manual}). You extend @code{home-shepherd-service-type} with
40568 new services; Guix Home then takes care of starting the @code{shepherd}
40569 daemon for you when you log in, which in turns starts the services you
40572 @defvr {Scheme Variable} home-shepherd-service-type
40573 The service type for the userland Shepherd, which allows one to manage
40574 long-running processes or one-shot tasks. User's Shepherd is not an
40575 init process (PID 1), but almost all other information described in
40576 (@pxref{Shepherd Services}) is applicable here too.
40578 This is the service type that extensions target when they want to create
40579 shepherd services (@pxref{Service Types and Services}, for an example).
40580 Each extension must pass a list of @code{<shepherd-service>}. Its
40581 value must be a @code{home-shepherd-configuration}, as described below.
40584 @deftp {Data Type} home-shepherd-configuration
40585 This data type represents the Shepherd's configuration.
40588 @item shepherd (default: @code{shepherd})
40589 The Shepherd package to use.
40591 @item auto-start? (default: @code{#t})
40592 Whether or not to start Shepherd on first login.
40594 @item services (default: @code{'()})
40595 A list of @code{<shepherd-service>} to start.
40596 You should probably use the service extension
40597 mechanism instead (@pxref{Shepherd Services}).
40602 @subsection Secure Shell
40604 @cindex secure shell client, configuration
40605 @cindex SSH client, configuration
40606 The @uref{https://www.openssh.com, OpenSSH package} includes a client,
40607 the @command{ssh} command, that allows you to connect to remote machines
40608 using the @acronym{SSH, secure shell} protocol. With the @code{(gnu
40609 home services ssh)} module, you can set up OpenSSH so that it works in a
40610 predictable fashion, almost independently of state on the local machine.
40611 To do that, you instantiate @code{home-openssh-service-type} in your
40612 Home configuration, as explained below.
40614 @defvr {Scheme Variable} home-openssh-service-type
40615 This is the type of the service to set up the OpenSSH client. It takes
40616 care of several things:
40620 providing a @file{~/.ssh/config} file based on your configuration so
40621 that @command{ssh} knows about hosts you regularly connect to and their
40622 associated parameters;
40625 providing a @file{~/.ssh/authorized_keys}, which lists public keys that
40626 the local SSH server, @command{sshd}, may accept to connect to this user
40630 optionally providing a @file{~/.ssh/known_hosts} file so that @file{ssh}
40631 can authenticate hosts you connect to.
40634 Here is an example of a service and its configuration that you could add
40635 to the @code{services} field of your @code{home-environment}:
40638 (service home-openssh-service-type
40639 (home-openssh-configuration
40641 (list (openssh-host (name "ci.guix.gnu.org")
40643 (openssh-host (name "chbouib")
40644 (host-name "chbouib.example.org")
40645 (user "supercharlie")
40647 (authorized-keys (list (local-file "alice.pub")))))
40650 The example above lists two hosts and their parameters. For instance,
40651 running @command{ssh chbouib} will automatically connect to
40652 @code{chbouib.example.org} on port 10022, logging in as user
40653 @samp{supercharlie}. Further, it marks the public key in
40654 @file{alice.pub} as authorized for incoming connections.
40656 The value associated with a @code{home-openssh-service-type} instance
40657 must be a @code{home-openssh-configuration} record, as describe below.
40660 @deftp {Data Type} home-openssh-configuration
40661 This is the datatype representing the OpenSSH client and server
40662 configuration in one's home environment. It contains the following
40666 @item @code{hosts} (default: @code{'()})
40667 A list of @code{openssh-host} records specifying host names and
40668 associated connection parameters (see below). This host list goes into
40669 @file{~/.ssh/config}, which @command{ssh} reads at startup.
40671 @item @code{known-hosts} (default: @code{*unspecified*})
40672 This must be either:
40676 @code{*unspecified*}, in which case @code{home-openssh-service-type}
40677 leaves it up to @command{ssh} and to the user to maintain the list of
40678 known hosts at @file{~/.ssh/known_hosts}, or
40681 a list of file-like objects, in which case those are concatenated and
40682 emitted as @file{~/.ssh/known_hosts}.
40685 The @file{~/.ssh/known_hosts} contains a list of host name/host key
40686 pairs that allow @command{ssh} to authenticate hosts you connect to and
40687 to detect possible impersonation attacks. By default, @command{ssh}
40688 updates it in a @dfn{TOFU, trust-on-first-use} fashion, meaning that it
40689 records the host's key in that file the first time you connect to it.
40690 This behavior is preserved when @code{known-hosts} is set to
40691 @code{*unspecified*}.
40693 If you instead provide a list of host keys upfront in the
40694 @code{known-hosts} field, your configuration becomes self-contained and
40695 stateless: it can be replicated elsewhere or at another point in time.
40696 Preparing this list can be relatively tedious though, which is why
40697 @code{*unspecified*} is kept as a default.
40699 @item @code{authorized-keys} (default: @code{'()})
40700 This must be a list of file-like objects, each of which containing an
40701 SSH public key that should be authorized to connect to this machine.
40703 Concretely, these files are concatenated and made available as
40704 @file{~/.ssh/authorized_keys}. If an OpenSSH server, @command{sshd}, is
40705 running on this machine, then it @emph{may} take this file into account:
40706 this is what @command{sshd} does by default, but be aware that it can
40707 also be configured to ignore it.
40711 @c %start of fragment
40713 @deftp {Data Type} openssh-host
40714 Available @code{openssh-host} fields are:
40717 @item @code{name} (type: string)
40718 Name of this host declaration.
40720 @item @code{host-name} (type: maybe-string)
40721 Host name---e.g., @code{"foo.example.org"} or @code{"192.168.1.2"}.
40723 @item @code{address-family} (type: address-family)
40724 Address family to use when connecting to this host: one of
40725 @code{AF_INET} (for IPv4 only), @code{AF_INET6} (for IPv6 only), or
40726 @code{*unspecified*} (allowing any address family).
40728 @item @code{identity-file} (type: maybe-string)
40729 The identity file to use---e.g., @code{"/home/charlie/.ssh/id_ed25519"}.
40731 @item @code{port} (type: maybe-natural-number)
40732 TCP port number to connect to.
40734 @item @code{user} (type: maybe-string)
40735 User name on the remote host.
40737 @item @code{forward-x11?} (default: @code{#f}) (type: boolean)
40738 Whether to forward remote client connections to the local X11 graphical
40741 @item @code{forward-x11-trusted?} (default: @code{#f}) (type: boolean)
40742 Whether remote X11 clients have full access to the original X11
40745 @item @code{forward-agent?} (default: @code{#f}) (type: boolean)
40746 Whether the authentication agent (if any) is forwarded to the remote
40749 @item @code{compression?} (default: @code{#f}) (type: boolean)
40750 Whether to compress data in transit.
40752 @item @code{proxy-command} (type: maybe-string)
40753 The command to use to connect to the server. As an example, a command
40754 to connect via an HTTP proxy at 192.0.2.0 would be: @code{"nc -X connect
40755 -x 192.0.2.0:8080 %h %p"}.
40757 @item @code{host-key-algorithms} (type: maybe-string-list)
40758 The list of accepted host key algorithms---e.g.,
40759 @code{'("ssh-ed25519")}.
40761 @item @code{accepted-key-types} (type: maybe-string-list)
40762 The list of accepted user public key types.
40764 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40765 Extra content appended as-is to this @code{Host} block in
40766 @file{~/.ssh/config}.
40773 @c %end of fragment
40776 @node Desktop Home Services
40777 @subsection Desktop Home Services
40779 The @code{(gnu home services desktop)} module provides services that you
40780 may find useful on ``desktop'' systems running a graphical user
40781 environment such as Xorg.
40783 @defvr {Scheme Variable} home-redshift-service-type
40784 This is the service type for @uref{https://github.com/jonls/redshift,
40785 Redshift}, a program that adjusts the display color temperature
40786 according to the time of day. Its associated value must be a
40787 @code{home-redshift-configuration} record, as shown below.
40789 A typical configuration, where we manually specify the latitude and
40790 longitude, might look like this:
40793 (service home-redshift-service-type
40794 (home-redshift-configuration
40795 (location-provider 'manual)
40796 (latitude 35.81) ;northern hemisphere
40797 (longitude -0.80))) ;west of Greenwich
40801 @deftp {Data Type} home-redshift-configuration
40802 Available @code{home-redshift-configuration} fields are:
40805 @item @code{redshift} (default: @code{redshift}) (type: file-like)
40806 Redshift package to use.
40808 @item @code{location-provider} (default: @code{geoclue2}) (type: symbol)
40809 Geolocation provider---@code{'manual} or @code{'geoclue2}. In the
40810 former case, you must also specify the @code{latitude} and
40811 @code{longitude} fields so Redshift can determine daytime at your place.
40812 In the latter case, the Geoclue system service must be running; it will
40813 be queried for location information.
40815 @item @code{adjustment-method} (default: @code{randr}) (type: symbol)
40816 Color adjustment method.
40818 @item @code{daytime-temperature} (default: @code{6500}) (type: integer)
40819 Daytime color temperature (kelvins).
40821 @item @code{nighttime-temperature} (default: @code{4500}) (type: integer)
40822 Nighttime color temperature (kelvins).
40824 @item @code{daytime-brightness} (type: maybe-inexact-number)
40825 Daytime screen brightness, between 0.1 and 1.0, or left unspecified.
40827 @item @code{nighttime-brightness} (type: maybe-inexact-number)
40828 Nighttime screen brightness, between 0.1 and 1.0, or left unspecified.
40830 @item @code{latitude} (type: maybe-inexact-number)
40831 Latitude, when @code{location-provider} is @code{'manual}.
40833 @item @code{longitude} (type: maybe-inexact-number)
40834 Longitude, when @code{location-provider} is @code{'manual}.
40836 @item @code{dawn-time} (type: maybe-string)
40837 Custom time for the transition from night to day in the
40838 morning---@code{"HH:MM"} format. When specified, solar elevation is not
40839 used to determine the daytime/nighttime period.
40841 @item @code{dusk-time} (type: maybe-string)
40842 Likewise, custom time for the transition from day to night in the
40845 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40846 Extra content appended as-is to the Redshift configuration file. Run
40847 @command{man redshift} for more information about the configuration file
40854 @node Guix Home Services
40855 @subsection Guix Home Services
40857 The @code{(gnu home services guix)} module provides services for
40858 user-specific Guix configuration.
40860 @defvr {Scheme Variable} home-channels-service-type
40861 This is the service type for managing
40862 @file{$XDG_CONFIG_HOME/guix/channels.scm}, the file that controls the
40863 channels received on @command{guix pull} (@pxref{Channels}). Its
40864 associated value is a list of @code{channel} records, defined in the
40865 @code{(guix channels)} module.
40867 Generally, it is better to extend this service than to directly
40868 configure it, as its default value is the default guix channel(s)
40869 defined by @code{%default-channels}. If you configure this service
40870 directly, be sure to include a guix channel. @xref{Specifying
40871 Additional Channels} and @ref{Using a Custom Guix Channel} for more
40874 A typical extension for adding a channel might look like this:
40877 (simple-service 'variant-packages-service
40878 home-channels-service-type
40881 (name 'variant-packages)
40882 (url "https://example.org/variant-packages.git")))
40886 @node Invoking guix home
40887 @section Invoking @code{guix home}
40889 Once you have written a home environment declaration (@pxref{Declaring
40890 the Home Environment,,,,}, it can be @dfn{instantiated} using the
40891 @command{guix home} command. The synopsis is:
40894 guix home @var{options}@dots{} @var{action} @var{file}
40897 @var{file} must be the name of a file containing a
40898 @code{home-environment} declaration. @var{action} specifies how the
40899 home environment is instantiated, but there are few auxiliary actions
40900 which don't instantiate it. Currently the following values are
40905 Display available home service type definitions that match the given
40906 regular expressions, sorted by relevance:
40909 @cindex shell-profile
40913 $ guix home search shell
40914 name: home-shell-profile
40915 location: gnu/home/services/shells.scm:100:2
40916 extends: home-files
40917 description: Create `~/.profile', which is used for environment initialization of POSIX compliant login shells.
40918 + This service type can be extended with a list of file-like objects.
40922 location: gnu/home/services/shells.scm:640:2
40923 extends: home-files home-profile
40924 description: Install and configure Fish, the friendly interactive shell.
40928 location: gnu/home/services/shells.scm:290:2
40929 extends: home-files home-profile
40930 description: Install and configure Zsh.
40934 location: gnu/home/services/shells.scm:508:2
40935 extends: home-files home-profile
40936 description: Install and configure GNU Bash.
40942 As for @command{guix search}, the result is written in
40943 @code{recutils} format, which makes it easy to filter the output
40944 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
40946 @cindex container, for @command{guix home}
40948 Spawn a shell in an isolated environment---a
40949 @dfn{container}---containing your home as specified by @var{file}.
40951 For example, this is how you would start an interactive shell in a
40952 container with your home:
40955 guix home container config.scm
40958 This is a throw-away container where you can lightheartedly fiddle with
40959 files; any changes made within the container, any process started---all
40960 this disappears as soon as you exit that shell.
40962 As with @command{guix shell}, several options control that container:
40967 Enable networking within the container (it is disabled by default).
40969 @item --expose=@var{source}[=@var{target}]
40970 @itemx --share=@var{source}[=@var{target}]
40971 As with @command{guix shell}, make directory @var{source} of the host
40972 system available as @var{target} inside the container---read-only if you
40973 pass @option{--expose}, and writable if you pass @option{--share}
40974 (@pxref{Invoking guix shell, @option{--expose} and @option{--share}}).
40977 Additionally, you can run a command in that container, instead of
40978 spawning an interactive shell. For instance, here is how you would
40979 check which Shepherd services are started in a throw-away home
40983 guix home container config.scm -- herd status
40986 The command to run in the container must come after @code{--} (double
40989 @cindex service type definition, editing
40990 @cindex editing, service type definition
40992 Edit or view the definition of the given Home service types.
40994 For example, the command below opens your editor, as specified by the
40995 @env{EDITOR} environment variable, on the definition of the
40996 @code{home-mcron} service type:
40999 guix home edit home-mcron
41003 Build the home environment described in @var{file}, and switch to it.
41004 Switching means that the activation script will be evaluated and (in
41005 basic scenario) symlinks to configuration files generated from
41006 @code{home-environment} declaration will be created in @file{~}. If the
41007 file with the same path already exists in home folder it will be moved
41008 to @file{~/@var{timestamp}-guix-home-legacy-configs-backup}, where @var{timestamp}
41009 is a current UNIX epoch time.
41012 It is highly recommended to run @command{guix pull} once before you run
41013 @command{guix home reconfigure} for the first time (@pxref{Invoking guix
41017 This effects all the configuration specified in @var{file}. The command
41018 starts Shepherd services specified in @var{file} that are not currently
41019 running; if a service is currently running, this command will arrange
41020 for it to be upgraded the next time it is stopped (e.g.@: by @code{herd
41021 stop @var{service}} or @code{herd restart @var{service}}).
41023 This command creates a new generation whose number is one greater than
41024 the current generation (as reported by @command{guix home
41025 list-generations}). If that generation already exists, it will be
41026 overwritten. This behavior mirrors that of @command{guix package}
41027 (@pxref{Invoking guix package}).
41029 @cindex provenance tracking, of the home environment
41030 Upon completion, the new home is deployed under @file{~/.guix-home}.
41031 This directory contains @dfn{provenance meta-data}: the list of channels
41032 in use (@pxref{Channels}) and @var{file} itself, when available. You
41033 can view the provenance information by running:
41039 This information is useful should you later want to inspect how this
41040 particular generation was built. In fact, assuming @var{file} is
41041 self-contained, you can later rebuild generation @var{n} of your
41042 home environment with:
41045 guix time-machine \
41046 -C /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/channels.scm -- \
41048 /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/configuration.scm
41052 You can think of it as some sort of built-in version control! Your
41053 home is not just a binary artifact: @emph{it carries its own source}.
41054 @c @xref{Service Reference, @code{provenance-service-type}}, for more
41055 @c information on provenance tracking.
41057 @c @footnote{This action (and the related actions
41058 @c @code{switch-generation} and @code{roll-back}) are usable after the
41059 @c home environment is initialized.}.
41061 @item switch-generation
41062 @cindex home generations
41063 Switch to an existing home generation. This action atomically switches
41064 the home profile to the specified home generation.
41066 The target generation can be specified explicitly by its generation
41067 number. For example, the following invocation would switch to home
41071 guix home switch-generation 7
41074 The target generation can also be specified relative to the current
41075 generation with the form @code{+N} or @code{-N}, where @code{+3} means
41076 ``3 generations ahead of the current generation,'' and @code{-1} means
41077 ``1 generation prior to the current generation.'' When specifying a
41078 negative value such as @code{-1}, you must precede it with @code{--} to
41079 prevent it from being parsed as an option. For example:
41082 guix home switch-generation -- -1
41085 This action will fail if the specified generation does not exist.
41088 @cindex rolling back
41089 Switch to the preceding home generation. This is the inverse
41090 of @command{reconfigure}, and it is exactly the same as invoking
41091 @command{switch-generation} with an argument of @code{-1}.
41093 @item delete-generations
41094 @cindex deleting home generations
41095 @cindex saving space
41096 Delete home generations, making them candidates for garbage collection
41097 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
41100 This works in the same way as @samp{guix package --delete-generations}
41101 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
41102 arguments, all home generations but the current one are deleted:
41105 guix home delete-generations
41108 You can also select the generations you want to delete. The example below
41109 deletes all the home generations that are more than two months old:
41112 guix home delete-generations 2m
41116 Build the derivation of the home environment, which includes all the
41117 configuration files and programs needed. This action does not actually
41121 Describe the current home generation: its file name, as well as
41122 provenance information when available.
41124 To show installed packages in the current home generation's profile, the
41125 @code{--list-installed} flag is provided, with the same syntax that is
41126 used in @command{guix package --list-installed} (@pxref{Invoking guix
41127 package}). For instance, the following command shows a table of all the
41128 packages with ``emacs'' in their name that are installed in the current
41129 home generation's profile:
41132 guix home describe --list-installed=emacs
41135 @item list-generations
41136 List a summary of each generation of the home environment available on
41137 disk, in a human-readable way. This is similar to the
41138 @option{--list-generations} option of @command{guix package}
41139 (@pxref{Invoking guix package}).
41141 Optionally, one can specify a pattern, with the same syntax that is used
41142 in @command{guix package --list-generations}, to restrict the list of
41143 generations displayed. For instance, the following command displays
41144 generations that are up to 10 days old:
41147 guix home list-generations 10d
41150 The @code{--list-installed} flag may also be specified, with the same
41151 syntax that is used in @command{guix home describe}. This may be
41152 helpful if trying to determine when a package was added to the home
41156 Generate a @dfn{home environment} from the packages in the default
41157 profile and configuration files found in the user's home directory. The
41158 configuration files will be copied to the specified directory, and a
41159 @file{home-configuration.scm} will be populated with the home
41160 environment. Note that not every home service that exists is supported
41161 (@pxref{Home Services}).
41164 $ guix home import ~/guix-config
41165 guix home: '/home/alice/guix-config' populated with all the Home configuration files
41169 And there's more! @command{guix home} also provides the following
41170 sub-commands to visualize how the services of your home environment
41171 relate to one another:
41174 @cindex service extension graph, of a home environment
41175 @item extension-graph
41176 Emit to standard output the @dfn{service extension graph} of the home
41177 environment defined in @var{file} (@pxref{Service Composition}, for more
41178 information on service extensions). By default the output is in
41179 Dot/Graphviz format, but you can choose a different format with
41180 @option{--graph-backend}, as with @command{guix graph} (@pxref{Invoking
41181 guix graph, @option{--backend}}):
41186 guix home extension-graph @var{file} | xdot -
41189 shows the extension relations among services.
41191 @cindex Shepherd dependency graph, for a home environment
41192 @item shepherd-graph
41193 Emit to standard output the @dfn{dependency graph} of shepherd services
41194 of the home environment defined in @var{file}. @xref{Shepherd
41195 Services}, for more information and for an example graph.
41197 Again, the default output format is Dot/Graphviz, but you can pass
41198 @option{--graph-backend} to select a different one.
41201 @var{options} can contain any of the common build options (@pxref{Common
41202 Build Options}). In addition, @var{options} can contain one of the
41207 @item --expression=@var{expr}
41208 @itemx -e @var{expr}
41209 Consider the home-environment @var{expr} evaluates to.
41210 This is an alternative to specifying a file which evaluates to a home
41213 @item --allow-downgrades
41214 Instruct @command{guix home reconfigure} to allow system downgrades.
41216 Just like @command{guix system}, @command{guix home reconfigure}, by
41217 default, prevents you from downgrading your home to older or unrelated
41218 revisions compared to the channel revisions that were used to deploy
41219 it---those shown by @command{guix home describe}. Using
41220 @option{--allow-downgrades} allows you to bypass that check, at the risk
41221 of downgrading your home---be careful!
41225 @node Documentation
41226 @chapter Documentation
41228 @cindex documentation, searching for
41229 @cindex searching for documentation
41230 @cindex Info, documentation format
41232 @cindex manual pages
41233 In most cases packages installed with Guix come with documentation.
41234 There are two main documentation formats: ``Info'', a browsable
41235 hypertext format used for GNU software, and ``manual pages'' (or ``man
41236 pages''), the linear documentation format traditionally found on Unix.
41237 Info manuals are accessed with the @command{info} command or with Emacs,
41238 and man pages are accessed using @command{man}.
41240 You can look for documentation of software installed on your system by
41241 keyword. For example, the following command searches for information
41242 about ``TLS'' in Info manuals:
41246 "(emacs)Network Security" -- STARTTLS
41247 "(emacs)Network Security" -- TLS
41248 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
41249 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
41254 The command below searches for the same keyword in man
41255 pages@footnote{The database searched by @command{man -k} is only created
41256 in profiles that contain the @code{man-db} package.}:
41260 SSL (7) - OpenSSL SSL/TLS library
41261 certtool (1) - GnuTLS certificate tool
41265 These searches are purely local to your computer so you have the
41266 guarantee that documentation you find corresponds to what you have
41267 actually installed, you can access it off-line, and your privacy is
41270 Once you have these results, you can view the relevant documentation by
41274 $ info "(gnutls)Core TLS API"
41284 Info manuals contain sections and indices as well as hyperlinks like
41285 those found in Web pages. The @command{info} reader (@pxref{Top, Info
41286 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
41287 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
41288 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
41289 Introduction}, for an introduction to Info navigation.
41291 @node Installing Debugging Files
41292 @chapter Installing Debugging Files
41294 @cindex debugging files
41295 Program binaries, as produced by the GCC compilers for instance, are
41296 typically written in the ELF format, with a section containing
41297 @dfn{debugging information}. Debugging information is what allows the
41298 debugger, GDB, to map binary code to source code; it is required to
41299 debug a compiled program in good conditions.
41301 This chapter explains how to use separate debug info when packages
41302 provide it, and how to rebuild packages with debug info when it's
41306 * Separate Debug Info:: Installing 'debug' outputs.
41307 * Rebuilding Debug Info:: Building missing debug info.
41310 @node Separate Debug Info
41311 @section Separate Debug Info
41313 The problem with debugging information is that is takes up a fair amount
41314 of disk space. For example, debugging information for the GNU C Library
41315 weighs in at more than 60 MiB@. Thus, as a user, keeping all the
41316 debugging info of all the installed programs is usually not an option.
41317 Yet, space savings should not come at the cost of an impediment to
41318 debugging---especially in the GNU system, which should make it easier
41319 for users to exert their computing freedom (@pxref{GNU Distribution}).
41321 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
41322 mechanism that allows users to get the best of both worlds: debugging
41323 information can be stripped from the binaries and stored in separate
41324 files. GDB is then able to load debugging information from those files,
41325 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
41328 The GNU distribution takes advantage of this by storing debugging
41329 information in the @code{lib/debug} sub-directory of a separate package
41330 output unimaginatively called @code{debug} (@pxref{Packages with
41331 Multiple Outputs}). Users can choose to install the @code{debug} output
41332 of a package when they need it. For instance, the following command
41333 installs the debugging information for the GNU C Library and for GNU
41337 guix install glibc:debug guile:debug
41340 GDB must then be told to look for debug files in the user's profile, by
41341 setting the @code{debug-file-directory} variable (consider setting it
41342 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
41346 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
41349 From there on, GDB will pick up debugging information from the
41350 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
41352 Below is an alternative GDB script which is useful when working with
41353 other profiles. It takes advantage of the optional Guile integration in
41354 GDB. This snippet is included by default on Guix System in the
41355 @file{~/.gdbinit} file.
41359 (use-modules (gdb))
41360 (execute (string-append "set debug-file-directory "
41361 (or (getenv "GDB_DEBUG_FILE_DIRECTORY")
41362 "~/.guix-profile/lib/debug")))
41366 In addition, you will most likely want GDB to be able to show the source
41367 code being debugged. To do that, you will have to unpack the source
41368 code of the package of interest (obtained with @code{guix build
41369 --source}, @pxref{Invoking guix build}), and to point GDB to that source
41370 directory using the @code{directory} command (@pxref{Source Path,
41371 @code{directory},, gdb, Debugging with GDB}).
41373 @c XXX: keep me up-to-date
41374 The @code{debug} output mechanism in Guix is implemented by the
41375 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
41376 opt-in---debugging information is available only for the packages with
41377 definitions explicitly declaring a @code{debug} output. To check
41378 whether a package has a @code{debug} output, use @command{guix package
41379 --list-available} (@pxref{Invoking guix package}).
41381 Read on for how to deal with packages lacking a @code{debug} output.
41383 @node Rebuilding Debug Info
41384 @section Rebuilding Debug Info
41386 @cindex debugging info, rebuilding
41387 As we saw above, some packages, but not all, provide debugging info in a
41388 @code{debug} output. What can you do when debugging info is missing?
41389 The @option{--with-debug-info} option provides a solution to that: it
41390 allows you to rebuild the package(s) for which debugging info is
41391 missing---and only those---and to graft those onto the application
41392 you're debugging. Thus, while it's not as fast as installing a
41393 @code{debug} output, it is relatively inexpensive.
41395 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
41396 and would like to see what's going on in GLib, a library that's deep
41397 down in its dependency graph. As it turns out, GLib does not have a
41398 @code{debug} output and the backtrace GDB shows is all sadness:
41402 #0 0x00007ffff5f92190 in g_getenv ()
41403 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
41404 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
41405 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
41406 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
41407 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
41408 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
41412 To address that, you install Inkscape linked against a variant GLib that
41413 contains debug info:
41416 guix install inkscape --with-debug-info=glib
41419 This time, debugging will be a whole lot nicer:
41422 $ gdb --args sh -c 'exec inkscape'
41425 Function "g_getenv" not defined.
41426 Make breakpoint pending on future shared library load? (y or [n]) y
41427 Breakpoint 1 (g_getenv) pending.
41429 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
41432 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
41433 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
41434 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
41435 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
41436 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
41442 Note that there can be packages for which @option{--with-debug-info}
41443 will not have the desired effect. @xref{Package Transformation Options,
41444 @option{--with-debug-info}}, for more information.
41446 @node Using TeX and LaTeX
41447 @chapter Using @TeX{} and @LaTeX{}
41449 @cindex @TeX{} packages
41450 @cindex @LaTeX{} packages
41451 Guix provides packages for the @TeX{}, @LaTeX{}, ConTeXt, LuaTeX, and
41452 related typesetting systems, taken from the
41453 @uref{https://www.tug.org/texlive/, @TeX{} Live distribution}. However,
41454 because @TeX{} Live is so huge and because finding your way in this maze
41455 is tricky, we thought that you, dear user, would welcome guidance on how
41456 to deploy the relevant packages so you can compile your @TeX{} and
41457 @LaTeX{} documents.
41459 @TeX{} Live currently comes in two flavors in Guix:
41463 The ``monolithic'' @code{texlive} package: it comes with @emph{every
41464 single @TeX{} Live package} (more than 7,000 of them), but it is huge
41465 (more than 4@tie{}GiB for a single package!).
41468 The ``modular'' @code{texlive-} packages: you install
41469 @code{texlive-base}, which provides core functionality and the main
41470 commands---@command{pdflatex}, @command{dvips}, @command{luatex},
41471 @command{mf}, etc.---together with individual packages that provide just
41472 the features you need---@code{texlive-listings} for the
41473 @code{listings} package, @code{texlive-hyperref} for @code{hyperref},
41474 @code{texlive-beamer} for Beamer, @code{texlive-pgf} for PGF/TikZ,
41478 We recommend using the modular package set because it is much less
41479 resource-hungry. To build your documents, you would use commands such
41483 guix shell texlive-base texlive-wrapfig \
41484 texlive-hyperref texlive-cm-super -- pdflatex doc.tex
41487 You can quickly end up with unreasonably long command lines though. The
41488 solution is to instead write a manifest, for example like this one:
41491 (specifications->manifest
41497 "texlive-microtype"
41498 "texlive-listings" "texlive-hyperref"
41503 ;; Additional fonts.
41504 "texlive-cm-super" "texlive-amsfonts"
41505 "texlive-times" "texlive-helvetic" "texlive-courier"))
41508 You can then pass it to any command with the @option{-m} option:
41511 guix shell -m manifest.scm -- pdflatex doc.tex
41514 @xref{Writing Manifests}, for more on
41515 manifests. In the future, we plan to provide packages for @TeX{} Live
41516 @dfn{collections}---``meta-packages'' such as @code{fontsrecommended},
41517 @code{humanities}, or @code{langarabic} that provide the set of packages
41518 needed in this particular domain. That will allow you to list fewer
41521 The main difficulty here is that using the modular package set forces
41522 you to select precisely the packages that you need. You can use
41523 @command{guix search}, but finding the right package can prove to be
41524 tedious. When a package is missing, @command{pdflatex} and similar
41525 commands fail with an obscure message along the lines of:
41528 doc.tex: File `tikz.sty' not found.
41529 doc.tex:7: Emergency stop.
41533 or, for a missing font:
41536 kpathsea: Running mktexmf phvr7t
41537 ! I can't find file `phvr7t'.
41540 How do you determine what the missing package is? In the first case,
41541 you'll find the answer by running:
41544 $ guix search texlive tikz
41550 In the second case, @command{guix search} turns up nothing. Instead,
41551 you can search the @TeX{} Live package database using the @command{tlmgr}
41555 $ guix shell texlive-base -- tlmgr info phvr7t
41556 tlmgr: cannot find package phvr7t, searching for other matches:
41558 Packages containing `phvr7t' in their title/description:
41560 Packages containing files matching `phvr7t':
41562 texmf-dist/fonts/tfm/adobe/helvetic/phvr7t.tfm
41563 texmf-dist/fonts/tfm/adobe/helvetic/phvr7tn.tfm
41564 texmf-dist/fonts/vf/adobe/helvetic/phvr7t.vf
41565 texmf-dist/fonts/vf/adobe/helvetic/phvr7tn.vf
41567 texmf-dist/tex4ht/ht-fonts/alias/adobe/helvetic/phvr7t.htf
41570 The file is available in the @TeX{} Live @code{helvetic} package, which is
41571 known in Guix as @code{texlive-helvetic}. Quite a ride, but we found
41574 There is one important limitation though: Guix currently provides a
41575 subset of the @TeX{} Live packages. If you stumble upon a missing
41576 package, you can try and import it (@pxref{Invoking guix import}):
41579 guix import texlive @var{package}
41582 Additional options include:
41587 Traverse the dependency graph of the given upstream package recursively
41588 and generate package expressions for all those packages that are not yet
41593 @TeX{} Live packaging is still very much work in progress, but you can
41594 help! @xref{Contributing}, for more information.
41597 @node Security Updates
41598 @chapter Security Updates
41600 @cindex security updates
41601 @cindex security vulnerabilities
41602 Occasionally, important security vulnerabilities are discovered in software
41603 packages and must be patched. Guix developers try hard to keep track of
41604 known vulnerabilities and to apply fixes as soon as possible in the
41605 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
41606 containing only security updates). The @command{guix lint} tool helps
41607 developers find out about vulnerable versions of software packages in the
41612 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
41613 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
41614 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
41618 @xref{Invoking guix lint}, for more information.
41620 Guix follows a functional
41621 package management discipline (@pxref{Introduction}), which implies
41622 that, when a package is changed, @emph{every package that depends on it}
41623 must be rebuilt. This can significantly slow down the deployment of
41624 fixes in core packages such as libc or Bash, since basically the whole
41625 distribution would need to be rebuilt. Using pre-built binaries helps
41626 (@pxref{Substitutes}), but deployment may still take more time than
41630 To address this, Guix implements @dfn{grafts}, a mechanism that allows
41631 for fast deployment of critical updates without the costs associated
41632 with a whole-distribution rebuild. The idea is to rebuild only the
41633 package that needs to be patched, and then to ``graft'' it onto packages
41634 explicitly installed by the user and that were previously referring to
41635 the original package. The cost of grafting is typically very low, and
41636 order of magnitudes lower than a full rebuild of the dependency chain.
41638 @cindex replacements of packages, for grafts
41639 For instance, suppose a security update needs to be applied to Bash.
41640 Guix developers will provide a package definition for the ``fixed''
41641 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
41642 Packages}). Then, the original package definition is augmented with a
41643 @code{replacement} field pointing to the package containing the bug fix:
41650 (replacement bash-fixed)))
41653 From there on, any package depending directly or indirectly on Bash---as
41654 reported by @command{guix gc --requisites} (@pxref{Invoking guix
41655 gc})---that is installed is automatically ``rewritten'' to refer to
41656 @code{bash-fixed} instead of @code{bash}. This grafting process takes
41657 time proportional to the size of the package, usually less than a
41658 minute for an ``average'' package on a recent machine. Grafting is
41659 recursive: when an indirect dependency requires grafting, then grafting
41660 ``propagates'' up to the package that the user is installing.
41662 Currently, the length of the name and version of the graft and that of
41663 the package it replaces (@code{bash-fixed} and @code{bash} in the example
41664 above) must be equal. This restriction mostly comes from the fact that
41665 grafting works by patching files, including binary files, directly.
41666 Other restrictions may apply: for instance, when adding a graft to a
41667 package providing a shared library, the original shared library and its
41668 replacement must have the same @code{SONAME} and be binary-compatible.
41670 The @option{--no-grafts} command-line option allows you to forcefully
41671 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
41675 guix build bash --no-grafts
41679 returns the store file name of the original Bash, whereas:
41686 returns the store file name of the ``fixed'', replacement Bash. This
41687 allows you to distinguish between the two variants of Bash.
41689 To verify which Bash your whole profile refers to, you can run
41690 (@pxref{Invoking guix gc}):
41693 guix gc -R $(readlink -f ~/.guix-profile) | grep bash
41697 @dots{} and compare the store file names that you get with those above.
41698 Likewise for a complete Guix system generation:
41701 guix gc -R $(guix system build my-config.scm) | grep bash
41704 Lastly, to check which Bash running processes are using, you can use the
41705 @command{lsof} command:
41708 lsof | grep /gnu/store/.*bash
41712 @node Bootstrapping
41713 @chapter Bootstrapping
41715 @c Adapted from the ELS 2013 paper.
41717 @cindex bootstrapping
41719 Bootstrapping in our context refers to how the distribution gets built
41720 ``from nothing''. Remember that the build environment of a derivation
41721 contains nothing but its declared inputs (@pxref{Introduction}). So
41722 there's an obvious chicken-and-egg problem: how does the first package
41723 get built? How does the first compiler get compiled?
41725 It is tempting to think of this question as one that only die-hard
41726 hackers may care about. However, while the answer to that question is
41727 technical in nature, its implications are wide-ranging. How the
41728 distribution is bootstrapped defines the extent to which we, as
41729 individuals and as a collective of users and hackers, can trust the
41730 software we run. It is a central concern from the standpoint of
41731 @emph{security} and from a @emph{user freedom} viewpoint.
41733 @cindex bootstrap binaries
41734 The GNU system is primarily made of C code, with libc at its core. The
41735 GNU build system itself assumes the availability of a Bourne shell and
41736 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
41737 `grep'. Furthermore, build programs---programs that run
41738 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
41739 (@pxref{Derivations}). Consequently, to be able to build anything at
41740 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
41741 Binutils, libc, and the other packages mentioned above---the
41742 @dfn{bootstrap binaries}.
41744 These bootstrap binaries are ``taken for granted'', though we can also
41745 re-create them if needed (@pxref{Preparing to Use the Bootstrap
41749 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
41750 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
41753 @node Reduced Binary Seed Bootstrap
41754 @section The Reduced Binary Seed Bootstrap
41756 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
41757 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
41758 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
41759 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
41760 ``taken for granted.''
41762 Taking the bootstrap binaries for granted means that we consider them to
41763 be a correct and trustworthy ``seed'' for building the complete system.
41764 Therein lies a problem: the combined size of these bootstrap binaries is
41765 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
41766 or even inspecting these is next to impossible.
41768 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
41769 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
41770 Source Bootstrap'' and while we are working towards that goal it would
41771 be hyperbole to use that term for what we do now.}.
41773 The Reduced Binary Seed bootstrap removes the most critical tools---from a
41774 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
41775 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
41776 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
41777 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
41779 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
41780 C Library are built from source. From here on the more traditional
41781 bootstrap process resumes. This approach has reduced the bootstrap
41782 binaries in size to about 145MB in Guix v1.1.
41784 The next step that Guix has taken is to replace the shell and all its
41785 utilities with implementations in Guile Scheme, the @emph{Scheme-only
41786 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
41787 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
41788 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
41789 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
41790 removed are now built from source.
41792 Building the GNU System from source is currently only possible by adding
41793 some historical GNU packages as intermediate steps@footnote{Packages
41794 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
41795 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
41796 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
41797 and GNU packages become more bootstrappable again (e.g., new releases of
41798 GNU Sed will also ship as gzipped tarballs again, as alternative to the
41799 hard to bootstrap @code{xz}-compression), this set of added packages can
41800 hopefully be reduced again.
41802 The graph below shows the resulting dependency graph for
41803 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
41804 traditional bootstrap of the rest of the Guix System.
41806 @c ./pre-inst-env guix graph -e '(@@ (gnu packages commencement) gcc-core-mesboot0)' | sed -re 's,((bootstrap-mescc-tools|bootstrap-mes|guile-bootstrap).*shape =) box,\1 ellipse,' > doc/images/gcc-core-mesboot0-graph.dot
41807 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
41809 The only significant binary bootstrap seeds that remain@footnote{
41810 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
41811 together with @code{mes}.} are a Scheme interpreter and a Scheme
41812 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
41813 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
41814 to get Guile running.}.
41816 This further reduction has brought down the size of the binary seed to
41817 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
41819 Work is ongoing to remove all binary blobs from our free software
41820 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
41821 is work to bring these bootstraps to the @code{arm-linux} and
41822 @code{aarch64-linux} architectures and to the Hurd.
41824 If you are interested, join us on @samp{#bootstrappable} on the Freenode
41825 IRC network or discuss on @email{bug-mes@@gnu.org} or
41826 @email{gash-devel@@nongnu.org}.
41828 @node Preparing to Use the Bootstrap Binaries
41829 @section Preparing to Use the Bootstrap Binaries
41831 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
41832 @c large image, it's hard to scroll. Oh well.
41833 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
41835 The figure above shows the very beginning of the dependency graph of the
41836 distribution, corresponding to the package definitions of the @code{(gnu
41837 packages bootstrap)} module. A similar figure can be generated with
41838 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
41841 guix graph -t derivation \
41842 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
41843 | dot -Tps > gcc.ps
41846 or, for the further Reduced Binary Seed bootstrap
41849 guix graph -t derivation \
41850 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
41851 | dot -Tps > mes.ps
41854 At this level of detail, things are
41855 slightly complex. First, Guile itself consists of an ELF executable,
41856 along with many source and compiled Scheme files that are dynamically
41857 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
41858 tarball shown in this graph. This tarball is part of Guix's ``source''
41859 distribution, and gets inserted into the store with @code{add-to-store}
41860 (@pxref{The Store}).
41862 But how do we write a derivation that unpacks this tarball and adds it
41863 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
41864 derivation---the first one that gets built---uses @code{bash} as its
41865 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
41866 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
41867 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
41868 the Guix source distribution, whose sole purpose is to allow the Guile
41869 tarball to be unpacked.
41871 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
41872 Guile that can be used to run subsequent build programs. Its first task
41873 is to download tarballs containing the other pre-built binaries---this
41874 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
41875 @code{ftp-client.scm} are used for this purpose. The
41876 @code{module-import.drv} derivations import those modules in a directory
41877 in the store, using the original layout. The
41878 @code{module-import-compiled.drv} derivations compile those modules, and
41879 write them in an output directory with the right layout. This
41880 corresponds to the @code{#:modules} argument of
41881 @code{build-expression->derivation} (@pxref{Derivations}).
41883 Finally, the various tarballs are unpacked by the derivations
41884 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
41885 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
41886 point we have a working C tool chain.
41888 @unnumberedsec Building the Build Tools
41890 Bootstrapping is complete when we have a full tool chain that does not
41891 depend on the pre-built bootstrap tools discussed above. This
41892 no-dependency requirement is verified by checking whether the files of
41893 the final tool chain contain references to the @file{/gnu/store}
41894 directories of the bootstrap inputs. The process that leads to this
41895 ``final'' tool chain is described by the package definitions found in
41896 the @code{(gnu packages commencement)} module.
41898 The @command{guix graph} command allows us to ``zoom out'' compared to
41899 the graph above, by looking at the level of package objects instead of
41900 individual derivations---remember that a package may translate to
41901 several derivations, typically one derivation to download its source,
41902 one to build the Guile modules it needs, and one to actually build the
41903 package from source. The command:
41906 guix graph -t bag \
41907 -e '(@@@@ (gnu packages commencement)
41908 glibc-final-with-bootstrap-bash)' | xdot -
41912 displays the dependency graph leading to the ``final'' C
41913 library@footnote{You may notice the @code{glibc-intermediate} label,
41914 suggesting that it is not @emph{quite} final, but as a good
41915 approximation, we will consider it final.}, depicted below.
41917 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
41919 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
41920 The first tool that gets built with the bootstrap binaries is
41921 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
41922 for all the following packages. From there Findutils and Diffutils get
41925 Then come the first-stage Binutils and GCC, built as pseudo cross
41926 tools---i.e., with @option{--target} equal to @option{--host}. They are
41927 used to build libc. Thanks to this cross-build trick, this libc is
41928 guaranteed not to hold any reference to the initial tool chain.
41930 From there the final Binutils and GCC (not shown above) are built. GCC
41931 uses @command{ld} from the final Binutils, and links programs against
41932 the just-built libc. This tool chain is used to build the other
41933 packages used by Guix and by the GNU Build System: Guile, Bash,
41936 And voilà! At this point we have the complete set of build tools that
41937 the GNU Build System expects. These are in the @code{%final-inputs}
41938 variable of the @code{(gnu packages commencement)} module, and are
41939 implicitly used by any package that uses @code{gnu-build-system}
41940 (@pxref{Build Systems, @code{gnu-build-system}}).
41943 @unnumberedsec Building the Bootstrap Binaries
41945 @cindex bootstrap binaries
41946 Because the final tool chain does not depend on the bootstrap binaries,
41947 those rarely need to be updated. Nevertheless, it is useful to have an
41948 automated way to produce them, should an update occur, and this is what
41949 the @code{(gnu packages make-bootstrap)} module provides.
41951 The following command builds the tarballs containing the bootstrap binaries
41952 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
41953 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
41954 and Guile, and a tarball containing a mixture of Coreutils and other basic
41955 command-line tools):
41958 guix build bootstrap-tarballs
41961 The generated tarballs are those that should be referred to in the
41962 @code{(gnu packages bootstrap)} module mentioned at the beginning of
41965 Still here? Then perhaps by now you've started to wonder: when do we
41966 reach a fixed point? That is an interesting question! The answer is
41967 unknown, but if you would like to investigate further (and have
41968 significant computational and storage resources to do so), then let us
41971 @unnumberedsec Reducing the Set of Bootstrap Binaries
41973 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
41974 binary code! Why is that a problem? It's a problem because these big chunks
41975 of binary code are practically non-auditable, which makes it hard to establish
41976 what source code produced them. Every unauditable binary also leaves us
41977 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
41978 paper @emph{Reflections on Trusting Trust}.
41980 This is mitigated by the fact that our bootstrap binaries were generated
41981 from an earlier Guix revision. Nevertheless it lacks the level of
41982 transparency that we get in the rest of the package dependency graph,
41983 where Guix always gives us a source-to-binary mapping. Thus, our goal
41984 is to reduce the set of bootstrap binaries to the bare minimum.
41986 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
41987 on-going projects to do that. One of these is about replacing the
41988 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
41989 of increasing complexity, which could be built from source starting from
41990 a simple and auditable assembler.
41992 Our first major achievement is the replacement of of GCC, the GNU C Library
41993 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
41994 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
41995 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
41996 bootstrapped yet and thus we inject them as binary seeds. We call this the
41997 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
41998 binaries! Also, it has eliminated the C compiler binary; i686-linux and
41999 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
42001 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
42002 also looking at any other bootstrap binaries. Your help is welcome!
42005 @chapter Porting to a New Platform
42007 As discussed above, the GNU distribution is self-contained, and
42008 self-containment is achieved by relying on pre-built ``bootstrap
42009 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
42010 operating system kernel, CPU architecture, and application binary
42011 interface (ABI). Thus, to port the distribution to a platform that is
42012 not yet supported, one must build those bootstrap binaries, and update
42013 the @code{(gnu packages bootstrap)} module to use them on that platform.
42015 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
42016 When everything goes well, and assuming the GNU tool chain supports the
42017 target platform, this can be as simple as running a command like this
42021 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
42024 For this to work, it is first required to register a new platform as
42025 defined in the @code{(guix platform)} module. A platform is making the
42026 connection between a GNU triplet (@pxref{Specifying Target Triplets, GNU
42027 configuration triplets,, autoconf, Autoconf}), the equivalent
42028 @var{system} in Nix notation, the name of the
42029 @var{glibc-dynamic-linker}, and the corresponding Linux architecture
42030 name if applicable.
42032 Once the bootstrap tarball are built, the @code{(gnu packages
42033 bootstrap)} module needs to be updated to refer to these binaries on the
42034 target platform. That is, the hashes and URLs of the bootstrap tarballs
42035 for the new platform must be added alongside those of the currently
42036 supported platforms. The bootstrap Guile tarball is treated specially:
42037 it is expected to be available locally, and @file{gnu/local.mk} has
42038 rules to download it for the supported architectures; a rule for the new
42039 platform must be added as well.
42041 In practice, there may be some complications. First, it may be that the
42042 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
42043 above) is not recognized by all the GNU tools. Typically, glibc
42044 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
42045 configure flag (see @code{gcc.scm} for examples of how to handle this).
42046 Second, some of the required packages could fail to build for that
42047 platform. Lastly, the generated binaries could be broken for some
42050 @c *********************************************************************
42051 @include contributing.texi
42053 @c *********************************************************************
42054 @node Acknowledgments
42055 @chapter Acknowledgments
42057 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
42058 which was designed and
42059 implemented by Eelco Dolstra, with contributions from other people (see
42060 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
42061 management, and promoted unprecedented features, such as transactional
42062 package upgrades and rollbacks, per-user profiles, and referentially
42063 transparent build processes. Without this work, Guix would not exist.
42065 The Nix-based software distributions, Nixpkgs and NixOS, have also been
42066 an inspiration for Guix.
42068 GNU@tie{}Guix itself is a collective work with contributions from a
42069 number of people. See the @file{AUTHORS} file in Guix for more
42070 information on these fine people. The @file{THANKS} file lists people
42071 who have helped by reporting bugs, taking care of the infrastructure,
42072 providing artwork and themes, making suggestions, and more---thank you!
42075 @c *********************************************************************
42076 @node GNU Free Documentation License
42077 @appendix GNU Free Documentation License
42078 @cindex license, GNU Free Documentation License
42079 @include fdl-1.3.texi
42081 @c *********************************************************************
42082 @node Concept Index
42083 @unnumbered Concept Index
42086 @node Programming Index
42087 @unnumbered Programming Index
42088 @syncodeindex tp fn
42089 @syncodeindex vr fn
42094 @c Local Variables:
42095 @c ispell-local-dictionary: "american";