6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
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110 Permission is granted to copy, distribute and/or modify this document
111 under the terms of the GNU Free Documentation License, Version 1.3 or
112 any later version published by the Free Software Foundation; with no
113 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
114 copy of the license is included in the section entitled ``GNU Free
115 Documentation License''.
118 @dircategory System administration
120 * Guix: (guix). Manage installed software and system configuration.
121 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
122 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
123 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
124 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
125 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
128 @dircategory Software development
130 * guix shell: (guix)Invoking guix shell. Creating software environments.
131 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
132 * guix build: (guix)Invoking guix build. Building packages.
133 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
137 @title GNU Guix Reference Manual
138 @subtitle Using the GNU Guix Functional Package Manager
139 @author The GNU Guix Developers
142 @vskip 0pt plus 1filll
143 Edition @value{EDITION} @*
151 @c *********************************************************************
155 This document describes GNU Guix version @value{VERSION}, a functional
156 package management tool written for the GNU system.
158 @c TRANSLATORS: You can replace the following paragraph with information on
159 @c how to join your own translation team and how to report issues with the
161 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
162 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
163 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
164 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
165 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
166 would like to translate it in your native language, consider joining
167 @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
168 Weblate} (@pxref{Translating Guix}).
171 * Introduction:: What is Guix about?
172 * Installation:: Installing Guix.
173 * System Installation:: Installing the whole operating system.
174 * System Troubleshooting Tips:: When things don't go as planned.
175 * Getting Started:: Your first steps.
176 * Package Management:: Package installation, upgrade, etc.
177 * Channels:: Customizing the package collection.
178 * Development:: Guix-aided software development.
179 * Programming Interface:: Using Guix in Scheme.
180 * Utilities:: Package management commands.
181 * Foreign Architectures:: Build for foreign architectures.
182 * System Configuration:: Configuring the operating system.
183 * Home Configuration:: Configuring the home environment.
184 * Documentation:: Browsing software user manuals.
185 * Installing Debugging Files:: Feeding the debugger.
186 * Using TeX and LaTeX:: Typesetting.
187 * Security Updates:: Deploying security fixes quickly.
188 * Bootstrapping:: GNU/Linux built from scratch.
189 * Porting:: Targeting another platform or kernel.
190 * Contributing:: Your help needed!
192 * Acknowledgments:: Thanks!
193 * GNU Free Documentation License:: The license of this manual.
194 * Concept Index:: Concepts.
195 * Programming Index:: Data types, functions, and variables.
198 --- The Detailed Node Listing ---
202 * Managing Software the Guix Way:: What's special.
203 * GNU Distribution:: The packages and tools.
207 * Binary Installation:: Getting Guix running in no time!
208 * Requirements:: Software needed to build and run Guix.
209 * Running the Test Suite:: Testing Guix.
210 * Setting Up the Daemon:: Preparing the build daemon's environment.
211 * Invoking guix-daemon:: Running the build daemon.
212 * Application Setup:: Application-specific setup.
213 * Upgrading Guix:: Upgrading Guix and its build daemon.
215 Setting Up the Daemon
217 * Build Environment Setup:: Preparing the isolated build environment.
218 * Daemon Offload Setup:: Offloading builds to remote machines.
219 * SELinux Support:: Using an SELinux policy for the daemon.
223 * Limitations:: What you can expect.
224 * Hardware Considerations:: Supported hardware.
225 * USB Stick and DVD Installation:: Preparing the installation medium.
226 * Preparing for Installation:: Networking, partitioning, etc.
227 * Guided Graphical Installation:: Easy graphical installation.
228 * Manual Installation:: Manual installation for wizards.
229 * After System Installation:: When installation succeeded.
230 * Installing Guix in a VM:: Guix System playground.
231 * Building the Installation Image:: How this comes to be.
233 System Troubleshooting Tips
235 * Chrooting into an existing system:: Fixing things from a chroot
239 * Keyboard Layout and Networking and Partitioning:: Initial setup.
240 * Proceeding with the Installation:: Installing.
244 * Features:: How Guix will make your life brighter.
245 * Invoking guix package:: Package installation, removal, etc.
246 * Substitutes:: Downloading pre-built binaries.
247 * Packages with Multiple Outputs:: Single source package, multiple outputs.
248 * Invoking guix gc:: Running the garbage collector.
249 * Invoking guix pull:: Fetching the latest Guix and distribution.
250 * Invoking guix time-machine:: Running an older revision of Guix.
251 * Inferiors:: Interacting with another revision of Guix.
252 * Invoking guix describe:: Display information about your Guix revision.
253 * Invoking guix archive:: Exporting and importing store files.
257 * Official Substitute Servers:: One particular source of substitutes.
258 * Substitute Server Authorization:: How to enable or disable substitutes.
259 * Getting Substitutes from Other Servers:: Substitute diversity.
260 * Substitute Authentication:: How Guix verifies substitutes.
261 * Proxy Settings:: How to get substitutes via proxy.
262 * Substitution Failure:: What happens when substitution fails.
263 * On Trusting Binaries:: How can you trust that binary blob?
267 * Specifying Additional Channels:: Extending the package collection.
268 * Using a Custom Guix Channel:: Using a customized Guix.
269 * Replicating Guix:: Running the @emph{exact same} Guix.
270 * Channel Authentication:: How Guix verifies what it fetches.
271 * Channels with Substitutes:: Using channels with available substitutes.
272 * Creating a Channel:: How to write your custom channel.
273 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
274 * Declaring Channel Dependencies:: How to depend on other channels.
275 * Specifying Channel Authorizations:: Defining channel authors authorizations.
276 * Primary URL:: Distinguishing mirror to original.
277 * Writing Channel News:: Communicating information to channel's users.
281 * Invoking guix shell:: Spawning one-off software environments.
282 * Invoking guix environment:: Setting up development environments.
283 * Invoking guix pack:: Creating software bundles.
284 * The GCC toolchain:: Working with languages supported by GCC.
285 * Invoking guix git authenticate:: Authenticating Git repositories.
287 Programming Interface
289 * Package Modules:: Packages from the programmer's viewpoint.
290 * Defining Packages:: Defining new packages.
291 * Defining Package Variants:: Customizing packages.
292 * Writing Manifests:: The bill of materials of your environment.
293 * Build Systems:: Specifying how packages are built.
294 * Build Phases:: Phases of the build process of a package.
295 * Build Utilities:: Helpers for your package definitions and more.
296 * Search Paths:: Declaring search path environment variables.
297 * The Store:: Manipulating the package store.
298 * Derivations:: Low-level interface to package derivations.
299 * The Store Monad:: Purely functional interface to the store.
300 * G-Expressions:: Manipulating build expressions.
301 * Invoking guix repl:: Programming Guix in Guile.
302 * Using Guix Interactively:: Fine-grain interaction at the REPL.
306 * package Reference:: The package data type.
307 * origin Reference:: The origin data type.
311 * Invoking guix build:: Building packages from the command line.
312 * Invoking guix edit:: Editing package definitions.
313 * Invoking guix download:: Downloading a file and printing its hash.
314 * Invoking guix hash:: Computing the cryptographic hash of a file.
315 * Invoking guix import:: Importing package definitions.
316 * Invoking guix refresh:: Updating package definitions.
317 * Invoking guix style:: Styling package definitions.
318 * Invoking guix lint:: Finding errors in package definitions.
319 * Invoking guix size:: Profiling disk usage.
320 * Invoking guix graph:: Visualizing the graph of packages.
321 * Invoking guix publish:: Sharing substitutes.
322 * Invoking guix challenge:: Challenging substitute servers.
323 * Invoking guix copy:: Copying to and from a remote store.
324 * Invoking guix container:: Process isolation.
325 * Invoking guix weather:: Assessing substitute availability.
326 * Invoking guix processes:: Listing client processes.
328 Invoking @command{guix build}
330 * Common Build Options:: Build options for most commands.
331 * Package Transformation Options:: Creating variants of packages.
332 * Additional Build Options:: Options specific to 'guix build'.
333 * Debugging Build Failures:: Real life packaging experience.
335 Foreign Architectures
336 * Cross-Compilation:: Cross-compiling for another architecture.
337 * Native Builds:: Targeting another architecture through native builds.
341 * Using the Configuration System:: Customizing your GNU system.
342 * operating-system Reference:: Detail of operating-system declarations.
343 * File Systems:: Configuring file system mounts.
344 * Mapped Devices:: Block device extra processing.
345 * Swap Space:: Backing RAM with disk space.
346 * User Accounts:: Specifying user accounts.
347 * Keyboard Layout:: How the system interprets key strokes.
348 * Locales:: Language and cultural convention settings.
349 * Services:: Specifying system services.
350 * Setuid Programs:: Programs running with elevated privileges.
351 * X.509 Certificates:: Authenticating HTTPS servers.
352 * Name Service Switch:: Configuring libc's name service switch.
353 * Initial RAM Disk:: Linux-Libre bootstrapping.
354 * Bootloader Configuration:: Configuring the boot loader.
355 * Invoking guix system:: Instantiating a system configuration.
356 * Invoking guix deploy:: Deploying a system configuration to a remote host.
357 * Running Guix in a VM:: How to run Guix System in a virtual machine.
358 * Defining Services:: Adding new service definitions.
360 Home Environment Configuration
362 * Invoking guix home:: Instantiating a home environment configuration.
366 * Base Services:: Essential system services.
367 * Scheduled Job Execution:: The mcron service.
368 * Log Rotation:: The rottlog service.
369 * Networking Setup:: Setting up network interfaces.
370 * Networking Services:: Firewall, SSH daemon, etc.
371 * Unattended Upgrades:: Automated system upgrades.
372 * X Window:: Graphical display.
373 * Printing Services:: Local and remote printer support.
374 * Desktop Services:: D-Bus and desktop services.
375 * Sound Services:: ALSA and Pulseaudio services.
376 * Database Services:: SQL databases, key-value stores, etc.
377 * Mail Services:: IMAP, POP3, SMTP, and all that.
378 * Messaging Services:: Messaging services.
379 * Telephony Services:: Telephony services.
380 * Monitoring Services:: Monitoring services.
381 * Kerberos Services:: Kerberos services.
382 * LDAP Services:: LDAP services.
383 * Web Services:: Web servers.
384 * Certificate Services:: TLS certificates via Let's Encrypt.
385 * DNS Services:: DNS daemons.
386 * VPN Services:: VPN daemons.
387 * Network File System:: NFS related services.
388 * Continuous Integration:: Cuirass and Laminar services.
389 * Power Management Services:: Extending battery life.
390 * Audio Services:: The MPD.
391 * Virtualization Services:: Virtualization services.
392 * Version Control Services:: Providing remote access to Git repositories.
393 * Game Services:: Game servers.
394 * PAM Mount Service:: Service to mount volumes when logging in.
395 * Guix Services:: Services relating specifically to Guix.
396 * Linux Services:: Services tied to the Linux kernel.
397 * Hurd Services:: Services specific for a Hurd System.
398 * Miscellaneous Services:: Other services.
402 * Service Composition:: The model for composing services.
403 * Service Types and Services:: Types and services.
404 * Service Reference:: API reference.
405 * Shepherd Services:: A particular type of service.
406 * Complex Configurations:: Defining bindings for complex configurations.
408 Installing Debugging Files
410 * Separate Debug Info:: Installing 'debug' outputs.
411 * Rebuilding Debug Info:: Building missing debug info.
415 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
416 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
421 @c *********************************************************************
423 @chapter Introduction
426 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
427 using the international phonetic alphabet (IPA).} is a package
428 management tool for and distribution of the GNU system.
429 Guix makes it easy for unprivileged
430 users to install, upgrade, or remove software packages, to roll back to a
431 previous package set, to build packages from source, and generally
432 assists with the creation and maintenance of software environments.
435 @cindex GuixSD, now Guix System
436 @cindex Guix System Distribution, now Guix System
437 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
438 complements the available tools without interference (@pxref{Installation}),
439 or you can use it as a standalone operating system distribution,
440 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
441 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
442 group everything under the ``Guix'' banner since, after all, Guix System is
443 readily available through the @command{guix system} command, even if you're
444 using a different distro underneath!}. @xref{GNU Distribution}.
447 * Managing Software the Guix Way:: What's special.
448 * GNU Distribution:: The packages and tools.
451 @node Managing Software the Guix Way
452 @section Managing Software the Guix Way
454 @cindex user interfaces
455 Guix provides a command-line package management interface
456 (@pxref{Package Management}), tools to help with software development
457 (@pxref{Development}), command-line utilities for more advanced usage
458 (@pxref{Utilities}), as well as Scheme programming interfaces
459 (@pxref{Programming Interface}).
461 Its @dfn{build daemon} is responsible for building packages on behalf of
462 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
463 binaries from authorized sources (@pxref{Substitutes}).
465 @cindex extensibility of the distribution
466 @cindex customization, of packages
467 Guix includes package definitions for many GNU and non-GNU packages, all
468 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
469 user's computing freedom}. It is @emph{extensible}: users can write
470 their own package definitions (@pxref{Defining Packages}) and make them
471 available as independent package modules (@pxref{Package Modules}). It
472 is also @emph{customizable}: users can @emph{derive} specialized package
473 definitions from existing ones, including from the command line
474 (@pxref{Package Transformation Options}).
476 @cindex functional package management
478 Under the hood, Guix implements the @dfn{functional package management}
479 discipline pioneered by Nix (@pxref{Acknowledgments}).
480 In Guix, the package build and installation process is seen
481 as a @emph{function}, in the mathematical sense. That function takes inputs,
482 such as build scripts, a compiler, and libraries, and
483 returns an installed package. As a pure function, its result depends
484 solely on its inputs---for instance, it cannot refer to software or
485 scripts that were not explicitly passed as inputs. A build function
486 always produces the same result when passed a given set of inputs. It
487 cannot alter the environment of the running system in
488 any way; for instance, it cannot create, modify, or delete files outside
489 of its build and installation directories. This is achieved by running
490 build processes in isolated environments (or @dfn{containers}), where only their
491 explicit inputs are visible.
494 The result of package build functions is @dfn{cached} in the file
495 system, in a special directory called @dfn{the store} (@pxref{The
496 Store}). Each package is installed in a directory of its own in the
497 store---by default under @file{/gnu/store}. The directory name contains
498 a hash of all the inputs used to build that package; thus, changing an
499 input yields a different directory name.
501 This approach is the foundation for the salient features of Guix: support
502 for transactional package upgrade and rollback, per-user installation, and
503 garbage collection of packages (@pxref{Features}).
506 @node GNU Distribution
507 @section GNU Distribution
510 Guix comes with a distribution of the GNU system consisting entirely of
511 free software@footnote{The term ``free'' here refers to the
512 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
513 users of that software}.}. The
514 distribution can be installed on its own (@pxref{System Installation}),
515 but it is also possible to install Guix as a package manager on top of
516 an installed GNU/Linux system (@pxref{Installation}). When we need to
517 distinguish between the two, we refer to the standalone distribution as
520 The distribution provides core GNU packages such as GNU libc, GCC, and
521 Binutils, as well as many GNU and non-GNU applications. The complete
522 list of available packages can be browsed
523 @url{https://www.gnu.org/software/guix/packages,on-line} or by
524 running @command{guix package} (@pxref{Invoking guix package}):
527 guix package --list-available
530 Our goal is to provide a practical 100% free software distribution of
531 Linux-based and other variants of GNU, with a focus on the promotion and
532 tight integration of GNU components, and an emphasis on programs and
533 tools that help users exert that freedom.
535 Packages are currently available on the following platforms:
540 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
543 Intel 32-bit architecture (IA32), Linux-Libre kernel.
546 ARMv7-A architecture with hard float, Thumb-2 and NEON,
547 using the EABI hard-float application binary interface (ABI),
548 and Linux-Libre kernel.
551 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
554 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
557 This configuration is experimental and under development. The easiest
558 way for you to give it a try is by setting up an instance of
559 @code{hurd-vm-service-type} on your GNU/Linux machine
560 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
561 @xref{Contributing}, on how to help!
563 @item mips64el-linux (unsupported)
564 little-endian 64-bit MIPS processors, specifically the Loongson series,
565 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
566 supported; in particular, there is no ongoing work to ensure that this
567 architecture still works. Should someone decide they wish to revive this
568 architecture then the code is still available.
570 @item powerpc-linux (unsupported)
571 big-endian 32-bit PowerPC processors, specifically the PowerPC G4 with
572 AltiVec support, and Linux-Libre kernel. This configuration is not
573 fully supported and there is no ongoing work to ensure this architecture
576 @item powerpc64le-linux
577 little-endian 64-bit Power ISA processors, Linux-Libre kernel. This
578 includes POWER9 systems such as the
579 @uref{https://www.fsf.org/news/talos-ii-mainboard-and-talos-ii-lite-mainboard-now-fsf-certified-to-respect-your-freedom,
580 RYF Talos II mainboard}. This platform is available as a "technology
581 preview": although it is supported, substitutes are not yet available
582 from the build farm (@pxref{Substitutes}), and some packages may fail to
583 build (@pxref{Tracking Bugs and Patches}). That said, the Guix
584 community is actively working on improving this support, and now is a
585 great time to try it and get involved!
588 little-endian 64-bit RISC-V processors, specifically RV64GC, and
589 Linux-Libre kernel. This platform is available as a "technology preview":
590 although it is supported, substitutes are not yet available from the
591 build farm (@pxref{Substitutes}), and some packages may fail to build
592 (@pxref{Tracking Bugs and Patches}). That said, the Guix community is
593 actively working on improving this support, and now is a great time to
594 try it and get involved!
598 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
599 configuration and Guix takes care of instantiating the configuration in a
600 transactional, reproducible, and stateless fashion (@pxref{System
601 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
602 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
603 Manual}), the well-known GNU utilities and tool chain, as well as the
604 graphical environment or system services of your choice.
606 Guix System is available on all the above platforms except
607 @code{mips64el-linux}, @code{powerpc-linux}, @code{powerpc64le-linux} and
608 @code{riscv64-linux}.
611 For information on porting to other architectures or kernels,
614 Building this distribution is a cooperative effort, and you are invited
615 to join! @xref{Contributing}, for information about how you can help.
618 @c *********************************************************************
620 @chapter Installation
622 @cindex installing Guix
625 We recommend the use of this
626 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
627 shell installer script} to install Guix on top of a running GNU/Linux system,
628 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
629 with the installation of the package manager, which can be done on top of a
630 running GNU/Linux system. If, instead, you want to install the complete GNU
631 operating system, @pxref{System Installation}.} The script automates the
632 download, installation, and initial configuration of Guix. It should be run
636 @cindex foreign distro
637 @cindex directories related to foreign distro
638 When installed on a foreign distro, GNU@tie{}Guix complements the available
639 tools without interference. Its data lives exclusively in two directories,
640 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
641 such as @file{/etc}, are left untouched.
643 Once installed, Guix can be updated by running @command{guix pull}
644 (@pxref{Invoking guix pull}).
646 If you prefer to perform the installation steps manually or want to tweak
647 them, you may find the following subsections useful. They describe the
648 software requirements of Guix, as well as how to install it manually and get
652 * Binary Installation:: Getting Guix running in no time!
653 * Requirements:: Software needed to build and run Guix.
654 * Running the Test Suite:: Testing Guix.
655 * Setting Up the Daemon:: Preparing the build daemon's environment.
656 * Invoking guix-daemon:: Running the build daemon.
657 * Application Setup:: Application-specific setup.
658 * Upgrading Guix:: Upgrading Guix and its build daemon.
661 @node Binary Installation
662 @section Binary Installation
664 @cindex installing Guix from binaries
665 @cindex installer script
666 This section describes how to install Guix on an arbitrary system from a
667 self-contained tarball providing binaries for Guix and for all its
668 dependencies. This is often quicker than installing from source, which
669 is described in the next sections. The only requirement is to have
672 @c Note duplicated from the ``Installation'' node.
674 We recommend the use of this
675 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
676 shell installer script}. The script automates the download, installation, and
677 initial configuration steps described below. It should be run as the root
678 user. As root, you can thus run this:
682 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
683 chmod +x guix-install.sh
687 If you're running Debian or a derivative such as Ubuntu, you can instead
688 install the package (it might be a version older than @value{VERSION}
689 but you can update it afterwards by running @samp{guix pull}):
692 sudo apt install guix
695 Likewise on openSUSE:
698 sudo zypper install guix
701 When you're done, @pxref{Application Setup} for extra configuration you
702 might need, and @ref{Getting Started} for your first steps!
705 Installing goes along these lines:
709 @cindex downloading Guix binary
710 Download the binary tarball from
711 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
712 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
713 @code{i686} (32-bits) machine already running the kernel Linux, and so on
714 (@pxref{GNU Distribution}).
716 @c The following is somewhat duplicated in ``System Installation''.
717 Make sure to download the associated @file{.sig} file and to verify the
718 authenticity of the tarball against it, along these lines:
721 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
722 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
725 If that command fails because you do not have the required public key,
726 then run this command to import it:
729 $ wget '@value{OPENPGP-SIGNING-KEY-URL}' \
730 -qO - | gpg --import -
734 and rerun the @code{gpg --verify} command.
736 Take note that a warning like ``This key is not certified with a trusted
737 signature!'' is normal.
739 @c end authentication part
742 Now, you need to become the @code{root} user. Depending on your distribution,
743 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
747 # tar --warning=no-timestamp -xf \
748 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
749 # mv var/guix /var/ && mv gnu /
752 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
753 The latter contains a ready-to-use profile for @code{root} (see next
756 Do @emph{not} unpack the tarball on a working Guix system since that
757 would overwrite its own essential files.
759 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
760 not emit warnings about ``implausibly old time stamps'' (such
761 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
763 They stem from the fact that all the
764 files in the archive have their modification time set to 1 (which
765 means January 1st, 1970). This is done on purpose to make sure the
766 archive content is independent of its creation time, thus making it
770 Make the profile available under @file{~root/.config/guix/current}, which is
771 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
774 # mkdir -p ~root/.config/guix
775 # ln -sf /var/guix/profiles/per-user/root/current-guix \
776 ~root/.config/guix/current
779 Source @file{etc/profile} to augment @env{PATH} and other relevant
780 environment variables:
783 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
784 source $GUIX_PROFILE/etc/profile
788 Create the group and user accounts for build users as explained below
789 (@pxref{Build Environment Setup}).
792 Run the daemon, and set it to automatically start on boot.
794 If your host distro uses the systemd init system, this can be achieved
797 @c Versions of systemd that supported symlinked service files are not
798 @c yet widely deployed, so we should suggest that users copy the service
801 @c See this thread for more information:
802 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
805 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
806 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
808 # systemctl enable --now gnu-store.mount guix-daemon
811 You may also want to arrange for @command{guix gc} to run periodically:
814 # cp ~root/.config/guix/current/lib/systemd/system/guix-gc.service \
815 ~root/.config/guix/current/lib/systemd/system/guix-gc.timer \
817 # systemctl enable --now guix-gc.timer
820 You may want to edit @file{guix-gc.service} to adjust the command line
821 options to fit your needs (@pxref{Invoking guix gc}).
823 If your host distro uses the Upstart init system:
826 # initctl reload-configuration
827 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
832 Otherwise, you can still start the daemon manually with:
835 # ~root/.config/guix/current/bin/guix-daemon \
836 --build-users-group=guixbuild
840 Make the @command{guix} command available to other users on the machine,
844 # mkdir -p /usr/local/bin
846 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
849 It is also a good idea to make the Info version of this manual available
853 # mkdir -p /usr/local/share/info
854 # cd /usr/local/share/info
855 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
859 That way, assuming @file{/usr/local/share/info} is in the search path,
860 running @command{info guix} will open this manual (@pxref{Other Info
861 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
865 @cindex substitutes, authorization thereof
866 To use substitutes from @code{@value{SUBSTITUTE-SERVER-1}},
867 @code{@value{SUBSTITUTE-SERVER-2}} or a mirror (@pxref{Substitutes}),
871 # guix archive --authorize < \
872 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
873 # guix archive --authorize < \
874 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
878 If you do not enable substitutes, Guix will end up building
879 @emph{everything} from source on your machine, making each installation
880 and upgrade very expensive. @xref{On Trusting Binaries}, for a
881 discussion of reasons why one might want do disable substitutes.
885 Each user may need to perform a few additional steps to make their Guix
886 environment ready for use, @pxref{Application Setup}.
889 Voilà, the installation is complete!
891 You can confirm that Guix is working by installing a sample package into
898 The binary installation tarball can be (re)produced and verified simply
899 by running the following command in the Guix source tree:
902 make guix-binary.@var{system}.tar.xz
906 ...@: which, in turn, runs:
909 guix pack -s @var{system} --localstatedir \
910 --profile-name=current-guix guix
913 @xref{Invoking guix pack}, for more info on this handy tool.
916 @section Requirements
918 This section lists requirements when building Guix from source. The
919 build procedure for Guix is the same as for other GNU software, and is
920 not covered here. Please see the files @file{README} and @file{INSTALL}
921 in the Guix source tree for additional details.
923 @cindex official website
924 GNU Guix is available for download from its website at
925 @url{https://www.gnu.org/software/guix/}.
927 GNU Guix depends on the following packages:
930 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x,
931 version 3.0.3 or later;
932 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
935 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
936 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
937 Guile,, gnutls-guile, GnuTLS-Guile});
939 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
941 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib},
942 version 0.1.0 or later;
943 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
944 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
946 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.5.0
948 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
950 @item @url{https://www.gnu.org/software/make/, GNU Make}.
953 The following dependencies are optional:
957 @c Note: We need at least 0.13.0 for #:nodelay.
958 Support for build offloading (@pxref{Daemon Offload Setup}) and
959 @command{guix copy} (@pxref{Invoking guix copy}) depends on
960 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
961 version 0.13.0 or later.
964 @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
965 compression and decompression in @command{guix publish} and for
966 substitutes (@pxref{Invoking guix publish}).
969 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
970 the @code{crate} importer (@pxref{Invoking guix import}).
973 @uref{https://www.nongnu.org/guile-lib/doc/ref/htmlprag/, Guile-Lib} for
974 the @code{go} importer (@pxref{Invoking guix import}) and for some of
975 the ``updaters'' (@pxref{Invoking guix refresh}).
978 When @url{http://www.bzip.org, libbz2} is available,
979 @command{guix-daemon} can use it to compress build logs.
982 Unless @option{--disable-daemon} was passed to @command{configure}, the
983 following packages are also needed:
986 @item @url{https://gnupg.org/, GNU libgcrypt};
987 @item @url{https://sqlite.org, SQLite 3};
988 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
992 @cindex state directory
993 When configuring Guix on a system that already has a Guix installation,
994 be sure to specify the same state directory as the existing installation
995 using the @option{--localstatedir} option of the @command{configure}
996 script (@pxref{Directory Variables, @code{localstatedir},, standards,
997 GNU Coding Standards}). Usually, this @var{localstatedir} option is
998 set to the value @file{/var}. The @command{configure} script protects
999 against unintended misconfiguration of @var{localstatedir} so you do not
1000 inadvertently corrupt your store (@pxref{The Store}).
1002 @node Running the Test Suite
1003 @section Running the Test Suite
1006 After a successful @command{configure} and @code{make} run, it is a good
1007 idea to run the test suite. It can help catch issues with the setup or
1008 environment, or bugs in Guix itself---and really, reporting test
1009 failures is a good way to help improve the software. To run the test
1016 Test cases can run in parallel: you can use the @code{-j} option of
1017 GNU@tie{}make to speed things up. The first run may take a few minutes
1018 on a recent machine; subsequent runs will be faster because the store
1019 that is created for test purposes will already have various things in
1022 It is also possible to run a subset of the tests by defining the
1023 @code{TESTS} makefile variable as in this example:
1026 make check TESTS="tests/store.scm tests/cpio.scm"
1029 By default, tests results are displayed at a file level. In order to
1030 see the details of every individual test cases, it is possible to define
1031 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
1034 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
1037 The underlying SRFI 64 custom Automake test driver used for the 'check'
1038 test suite (located at @file{build-aux/test-driver.scm}) also allows
1039 selecting which test cases to run at a finer level, via its
1040 @option{--select} and @option{--exclude} options. Here's an example, to
1041 run all the test cases from the @file{tests/packages.scm} test file
1042 whose names start with ``transaction-upgrade-entry'':
1045 export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
1046 make check TESTS="tests/packages.scm"
1049 Those wishing to inspect the results of failed tests directly from the
1050 command line can add the @option{--errors-only=yes} option to the
1051 @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
1052 Automake makefile variable, as in:
1055 make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
1058 The @option{--show-duration=yes} option can be used to print the
1059 duration of the individual test cases, when used in combination with
1060 @option{--brief=no}:
1063 make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
1066 @xref{Parallel Test Harness,,,automake,GNU Automake} for more
1067 information about the Automake Parallel Test Harness.
1069 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
1070 @file{test-suite.log} file. Please specify the Guix version being used
1071 as well as version numbers of the dependencies (@pxref{Requirements}) in
1074 Guix also comes with a whole-system test suite that tests complete
1075 Guix System instances. It can only run on systems where
1076 Guix is already installed, using:
1083 or, again, by defining @code{TESTS} to select a subset of tests to run:
1086 make check-system TESTS="basic mcron"
1089 These system tests are defined in the @code{(gnu tests @dots{})}
1090 modules. They work by running the operating systems under test with
1091 lightweight instrumentation in a virtual machine (VM). They can be
1092 computationally intensive or rather cheap, depending on whether
1093 substitutes are available for their dependencies (@pxref{Substitutes}).
1094 Some of them require a lot of storage space to hold VM images.
1096 Again in case of test failures, please send @email{bug-guix@@gnu.org}
1099 @node Setting Up the Daemon
1100 @section Setting Up the Daemon
1103 Operations such as building a package or running the garbage collector
1104 are all performed by a specialized process, the @dfn{build daemon}, on
1105 behalf of clients. Only the daemon may access the store and its
1106 associated database. Thus, any operation that manipulates the store
1107 goes through the daemon. For instance, command-line tools such as
1108 @command{guix package} and @command{guix build} communicate with the
1109 daemon (@i{via} remote procedure calls) to instruct it what to do.
1111 The following sections explain how to prepare the build daemon's
1112 environment. See also @ref{Substitutes}, for information on how to allow
1113 the daemon to download pre-built binaries.
1116 * Build Environment Setup:: Preparing the isolated build environment.
1117 * Daemon Offload Setup:: Offloading builds to remote machines.
1118 * SELinux Support:: Using an SELinux policy for the daemon.
1121 @node Build Environment Setup
1122 @subsection Build Environment Setup
1124 @cindex build environment
1125 In a standard multi-user setup, Guix and its daemon---the
1126 @command{guix-daemon} program---are installed by the system
1127 administrator; @file{/gnu/store} is owned by @code{root} and
1128 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
1129 Guix tools to build packages or otherwise access the store, and the
1130 daemon will do it on their behalf, ensuring that the store is kept in a
1131 consistent state, and allowing built packages to be shared among users.
1134 When @command{guix-daemon} runs as @code{root}, you may not want package
1135 build processes themselves to run as @code{root} too, for obvious
1136 security reasons. To avoid that, a special pool of @dfn{build users}
1137 should be created for use by build processes started by the daemon.
1138 These build users need not have a shell and a home directory: they will
1139 just be used when the daemon drops @code{root} privileges in build
1140 processes. Having several such users allows the daemon to launch
1141 distinct build processes under separate UIDs, which guarantees that they
1142 do not interfere with each other---an essential feature since builds are
1143 regarded as pure functions (@pxref{Introduction}).
1145 On a GNU/Linux system, a build user pool may be created like this (using
1146 Bash syntax and the @code{shadow} commands):
1148 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
1149 @c for why `-G' is needed.
1151 # groupadd --system guixbuild
1152 # for i in $(seq -w 1 10);
1154 useradd -g guixbuild -G guixbuild \
1155 -d /var/empty -s $(which nologin) \
1156 -c "Guix build user $i" --system \
1162 The number of build users determines how many build jobs may run in
1163 parallel, as specified by the @option{--max-jobs} option
1164 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1165 @command{guix system vm} and related commands, you may need to add the
1166 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1167 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1168 (@pxref{Invoking guix system}).
1170 The @code{guix-daemon} program may then be run as @code{root} with the
1171 following command@footnote{If your machine uses the systemd init system,
1172 copying the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1173 file to @file{/etc/systemd/system} will ensure that
1174 @command{guix-daemon} is automatically started. Similarly, if your
1175 machine uses the Upstart init system, copy the
1176 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1177 file to @file{/etc/init}.}:
1180 # guix-daemon --build-users-group=guixbuild
1185 This way, the daemon starts build processes in a chroot, under one of
1186 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1187 environment contains nothing but:
1189 @c Keep this list in sync with libstore/build.cc! -----------------------
1192 a minimal @code{/dev} directory, created mostly independently from the
1193 host @code{/dev}@footnote{``Mostly'', because while the set of files
1194 that appear in the chroot's @code{/dev} is fixed, most of these files
1195 can only be created if the host has them.};
1198 the @code{/proc} directory; it only shows the processes of the container
1199 since a separate PID name space is used;
1202 @file{/etc/passwd} with an entry for the current user and an entry for
1206 @file{/etc/group} with an entry for the user's group;
1209 @file{/etc/hosts} with an entry that maps @code{localhost} to
1213 a writable @file{/tmp} directory.
1216 The chroot does not contain a @file{/home} directory, and the @env{HOME}
1217 environment variable is set to the non-existent
1218 @file{/homeless-shelter}. This helps to highlight inappropriate uses of
1219 @env{HOME} in the build scripts of packages.
1221 You can influence the directory where the daemon stores build trees
1222 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1223 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1224 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1225 This way, the value of @env{TMPDIR} does not leak inside build
1226 environments, which avoids discrepancies in cases where build processes
1227 capture the name of their build tree.
1231 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1232 environment variables for HTTP and HTTPS downloads it performs, be it
1233 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1234 (@pxref{Substitutes}).
1236 If you are installing Guix as an unprivileged user, it is still possible
1237 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1238 However, build processes will not be isolated from one another, and not
1239 from the rest of the system. Thus, build processes may interfere with
1240 each other, and may access programs, libraries, and other files
1241 available on the system---making it much harder to view them as
1242 @emph{pure} functions.
1245 @node Daemon Offload Setup
1246 @subsection Using the Offload Facility
1250 When desired, the build daemon can @dfn{offload} derivation builds to
1251 other machines running Guix, using the @code{offload} @dfn{build
1252 hook}@footnote{This feature is available only when
1253 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1254 present.}. When that feature is enabled, a list of user-specified build
1255 machines is read from @file{/etc/guix/machines.scm}; every time a build
1256 is requested, for instance via @code{guix build}, the daemon attempts to
1257 offload it to one of the machines that satisfy the constraints of the
1258 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1259 A single machine can have multiple system types, either because its
1260 architecture natively supports it, via emulation
1261 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1262 or both. Missing prerequisites for the build are
1263 copied over SSH to the target machine, which then proceeds with the
1264 build; upon success the output(s) of the build are copied back to the
1265 initial machine. The offload facility comes with a basic scheduler that
1266 attempts to select the best machine. The best machine is chosen among
1267 the available machines based on criteria such as:
1271 The availability of a build slot. A build machine can have as many
1272 build slots (connections) as the value of the @code{parallel-builds}
1273 field of its @code{build-machine} object.
1276 Its relative speed, as defined via the @code{speed} field of its
1277 @code{build-machine} object.
1280 Its load. The normalized machine load must be lower than a threshold
1281 value, configurable via the @code{overload-threshold} field of its
1282 @code{build-machine} object.
1285 Disk space availability. More than a 100 MiB must be available.
1288 The @file{/etc/guix/machines.scm} file typically looks like this:
1291 (list (build-machine
1292 (name "eightysix.example.org")
1293 (systems (list "x86_64-linux" "i686-linux"))
1294 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1296 (speed 2.)) ;incredibly fast!
1299 (name "armeight.example.org")
1300 (systems (list "aarch64-linux"))
1301 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1304 ;; Remember 'guix offload' is spawned by
1305 ;; 'guix-daemon' as root.
1306 (private-key "/root/.ssh/identity-for-guix")))
1310 In the example above we specify a list of two build machines, one for
1311 the @code{x86_64} and @code{i686} architectures and one for the
1312 @code{aarch64} architecture.
1314 In fact, this file is---not surprisingly!---a Scheme file that is
1315 evaluated when the @code{offload} hook is started. Its return value
1316 must be a list of @code{build-machine} objects. While this example
1317 shows a fixed list of build machines, one could imagine, say, using
1318 DNS-SD to return a list of potential build machines discovered in the
1319 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1320 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1323 @deftp {Data Type} build-machine
1324 This data type represents build machines to which the daemon may offload
1325 builds. The important fields are:
1330 The host name of the remote machine.
1333 The system types the remote machine supports---e.g., @code{(list
1334 "x86_64-linux" "i686-linux")}.
1337 The user account to use when connecting to the remote machine over SSH.
1338 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1339 allow non-interactive logins.
1342 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1343 This is used to authenticate the machine when we connect to it. It is a
1344 long string that looks like this:
1347 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1350 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1351 key can be found in a file such as
1352 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1354 If the machine is running the SSH daemon of GNU@tie{}lsh,
1355 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1356 similar file. It can be converted to the OpenSSH format using
1357 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1360 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1361 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1366 A number of optional fields may be specified:
1370 @item @code{port} (default: @code{22})
1371 Port number of SSH server on the machine.
1373 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1374 The SSH private key file to use when connecting to the machine, in
1375 OpenSSH format. This key must not be protected with a passphrase.
1377 Note that the default value is the private key @emph{of the root
1378 account}. Make sure it exists if you use the default.
1380 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1381 @itemx @code{compression-level} (default: @code{3})
1382 The SSH-level compression methods and compression level requested.
1384 Note that offloading relies on SSH compression to reduce bandwidth usage
1385 when transferring files to and from build machines.
1387 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1388 File name of the Unix-domain socket @command{guix-daemon} is listening
1391 @item @code{overload-threshold} (default: @code{0.6})
1392 The load threshold above which a potential offload machine is
1393 disregarded by the offload scheduler. The value roughly translates to
1394 the total processor usage of the build machine, ranging from 0.0 (0%) to
1395 1.0 (100%). It can also be disabled by setting
1396 @code{overload-threshold} to @code{#f}.
1398 @item @code{parallel-builds} (default: @code{1})
1399 The number of builds that may run in parallel on the machine.
1401 @item @code{speed} (default: @code{1.0})
1402 A ``relative speed factor''. The offload scheduler will tend to prefer
1403 machines with a higher speed factor.
1405 @item @code{features} (default: @code{'()})
1406 A list of strings denoting specific features supported by the machine.
1407 An example is @code{"kvm"} for machines that have the KVM Linux modules
1408 and corresponding hardware support. Derivations can request features by
1409 name, and they will be scheduled on matching build machines.
1414 The @command{guix} command must be in the search path on the build
1415 machines. You can check whether this is the case by running:
1418 ssh build-machine guix repl --version
1421 There is one last thing to do once @file{machines.scm} is in place. As
1422 explained above, when offloading, files are transferred back and forth
1423 between the machine stores. For this to work, you first need to
1424 generate a key pair on each machine to allow the daemon to export signed
1425 archives of files from the store (@pxref{Invoking guix archive}):
1428 # guix archive --generate-key
1432 Each build machine must authorize the key of the master machine so that
1433 it accepts store items it receives from the master:
1436 # guix archive --authorize < master-public-key.txt
1440 Likewise, the master machine must authorize the key of each build machine.
1442 All the fuss with keys is here to express pairwise mutual trust
1443 relations between the master and the build machines. Concretely, when
1444 the master receives files from a build machine (and @i{vice versa}), its
1445 build daemon can make sure they are genuine, have not been tampered
1446 with, and that they are signed by an authorized key.
1448 @cindex offload test
1449 To test whether your setup is operational, run this command on the
1456 This will attempt to connect to each of the build machines specified in
1457 @file{/etc/guix/machines.scm}, make sure Guix is
1458 available on each machine, attempt to export to the machine and import
1459 from it, and report any error in the process.
1461 If you want to test a different machine file, just specify it on the
1465 # guix offload test machines-qualif.scm
1468 Last, you can test the subset of the machines whose name matches a
1469 regular expression like this:
1472 # guix offload test machines.scm '\.gnu\.org$'
1475 @cindex offload status
1476 To display the current load of all build hosts, run this command on the
1480 # guix offload status
1484 @node SELinux Support
1485 @subsection SELinux Support
1487 @cindex SELinux, daemon policy
1488 @cindex mandatory access control, SELinux
1489 @cindex security, guix-daemon
1490 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1491 can be installed on a system where SELinux is enabled, in order to label
1492 Guix files and to specify the expected behavior of the daemon. Since
1493 Guix System does not provide an SELinux base policy, the daemon policy cannot
1494 be used on Guix System.
1496 @subsubsection Installing the SELinux policy
1497 @cindex SELinux, policy installation
1498 To install the policy run this command as root:
1501 semodule -i etc/guix-daemon.cil
1504 Then relabel the file system with @code{restorecon} or by a different
1505 mechanism provided by your system.
1507 Once the policy is installed, the file system has been relabeled, and
1508 the daemon has been restarted, it should be running in the
1509 @code{guix_daemon_t} context. You can confirm this with the following
1513 ps -Zax | grep guix-daemon
1516 Monitor the SELinux log files as you run a command like @code{guix build
1517 hello} to convince yourself that SELinux permits all necessary
1520 @subsubsection Limitations
1521 @cindex SELinux, limitations
1523 This policy is not perfect. Here is a list of limitations or quirks
1524 that should be considered when deploying the provided SELinux policy for
1529 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1530 operations involve contexts that have anything to do with
1531 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1532 but it would be preferable to define socket rules for only this label.
1535 @code{guix gc} cannot access arbitrary links to profiles. By design,
1536 the file label of the destination of a symlink is independent of the
1537 file label of the link itself. Although all profiles under
1538 $localstatedir are labelled, the links to these profiles inherit the
1539 label of the directory they are in. For links in the user’s home
1540 directory this will be @code{user_home_t}. But for links from the root
1541 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1542 directory, etc, this won’t work. @code{guix gc} would be prevented from
1543 reading and following these links.
1546 The daemon’s feature to listen for TCP connections might no longer work.
1547 This might require extra rules, because SELinux treats network sockets
1548 differently from files.
1551 Currently all files with a name matching the regular expression
1552 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1553 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1554 that name in any profile would be permitted to run in the
1555 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1556 build a package that provides this executable and convince a user to
1557 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1558 At that point SELinux could not prevent it from accessing files that are
1559 allowed for processes in that domain.
1561 You will need to relabel the store directory after all upgrades to
1562 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1563 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1564 or by other means provided by your operating system.
1566 We could generate a much more restrictive policy at installation time,
1567 so that only the @emph{exact} file name of the currently installed
1568 @code{guix-daemon} executable would be labelled with
1569 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1570 The downside is that root would have to install or upgrade the policy at
1571 installation time whenever the Guix package that provides the
1572 effectively running @code{guix-daemon} executable is upgraded.
1575 @node Invoking guix-daemon
1576 @section Invoking @command{guix-daemon}
1578 The @command{guix-daemon} program implements all the functionality to
1579 access the store. This includes launching build processes, running the
1580 garbage collector, querying the availability of a build result, etc. It
1581 is normally run as @code{root} like this:
1584 # guix-daemon --build-users-group=guixbuild
1587 @cindex socket activation, for @command{guix-daemon}
1588 This daemon can also be started following the systemd ``socket
1589 activation'' protocol (@pxref{Service De- and Constructors,
1590 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
1592 For details on how to set it up, @pxref{Setting Up the Daemon}.
1595 @cindex container, build environment
1596 @cindex build environment
1597 @cindex reproducible builds
1598 By default, @command{guix-daemon} launches build processes under
1599 different UIDs, taken from the build group specified with
1600 @option{--build-users-group}. In addition, each build process is run in a
1601 chroot environment that only contains the subset of the store that the
1602 build process depends on, as specified by its derivation
1603 (@pxref{Programming Interface, derivation}), plus a set of specific
1604 system directories. By default, the latter contains @file{/dev} and
1605 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1606 @dfn{container}: in addition to having its own file system tree, it has
1607 a separate mount name space, its own PID name space, network name space,
1608 etc. This helps achieve reproducible builds (@pxref{Features}).
1610 When the daemon performs a build on behalf of the user, it creates a
1611 build directory under @file{/tmp} or under the directory specified by
1612 its @env{TMPDIR} environment variable. This directory is shared with
1613 the container for the duration of the build, though within the container,
1614 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1616 The build directory is automatically deleted upon completion, unless the
1617 build failed and the client specified @option{--keep-failed}
1618 (@pxref{Common Build Options, @option{--keep-failed}}).
1620 The daemon listens for connections and spawns one sub-process for each session
1621 started by a client (one of the @command{guix} sub-commands). The
1622 @command{guix processes} command allows you to get an overview of the activity
1623 on your system by viewing each of the active sessions and clients.
1624 @xref{Invoking guix processes}, for more information.
1626 The following command-line options are supported:
1629 @item --build-users-group=@var{group}
1630 Take users from @var{group} to run build processes (@pxref{Setting Up
1631 the Daemon, build users}).
1633 @item --no-substitutes
1635 Do not use substitutes for build products. That is, always build things
1636 locally instead of allowing downloads of pre-built binaries
1637 (@pxref{Substitutes}).
1639 When the daemon runs with @option{--no-substitutes}, clients can still
1640 explicitly enable substitution @i{via} the @code{set-build-options}
1641 remote procedure call (@pxref{The Store}).
1643 @anchor{daemon-substitute-urls}
1644 @item --substitute-urls=@var{urls}
1645 Consider @var{urls} the default whitespace-separated list of substitute
1646 source URLs. When this option is omitted,
1647 @indicateurl{@value{SUBSTITUTE-URLS}} is used.
1649 This means that substitutes may be downloaded from @var{urls}, as long
1650 as they are signed by a trusted signature (@pxref{Substitutes}).
1652 @xref{Getting Substitutes from Other Servers}, for more information on
1653 how to configure the daemon to get substitutes from other servers.
1657 Do not use offload builds to other machines (@pxref{Daemon Offload
1658 Setup}). That is, always build things locally instead of offloading
1659 builds to remote machines.
1661 @item --cache-failures
1662 Cache build failures. By default, only successful builds are cached.
1664 When this option is used, @command{guix gc --list-failures} can be used
1665 to query the set of store items marked as failed; @command{guix gc
1666 --clear-failures} removes store items from the set of cached failures.
1667 @xref{Invoking guix gc}.
1669 @item --cores=@var{n}
1671 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1674 The default value is @code{0}, but it may be overridden by clients, such
1675 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1678 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1679 in the build process, which can then use it to exploit internal
1680 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1682 @item --max-jobs=@var{n}
1684 Allow at most @var{n} build jobs in parallel. The default value is
1685 @code{1}. Setting it to @code{0} means that no builds will be performed
1686 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1687 Setup}), or simply fail.
1689 @item --max-silent-time=@var{seconds}
1690 When the build or substitution process remains silent for more than
1691 @var{seconds}, terminate it and report a build failure.
1693 The default value is @code{0}, which disables the timeout.
1695 The value specified here can be overridden by clients (@pxref{Common
1696 Build Options, @option{--max-silent-time}}).
1698 @item --timeout=@var{seconds}
1699 Likewise, when the build or substitution process lasts for more than
1700 @var{seconds}, terminate it and report a build failure.
1702 The default value is @code{0}, which disables the timeout.
1704 The value specified here can be overridden by clients (@pxref{Common
1705 Build Options, @option{--timeout}}).
1707 @item --rounds=@var{N}
1708 Build each derivation @var{n} times in a row, and raise an error if
1709 consecutive build results are not bit-for-bit identical. Note that this
1710 setting can be overridden by clients such as @command{guix build}
1711 (@pxref{Invoking guix build}).
1713 When used in conjunction with @option{--keep-failed}, the differing
1714 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1715 This makes it easy to look for differences between the two results.
1718 Produce debugging output.
1720 This is useful to debug daemon start-up issues, but then it may be
1721 overridden by clients, for example the @option{--verbosity} option of
1722 @command{guix build} (@pxref{Invoking guix build}).
1724 @item --chroot-directory=@var{dir}
1725 Add @var{dir} to the build chroot.
1727 Doing this may change the result of build processes---for instance if
1728 they use optional dependencies found in @var{dir} when it is available,
1729 and not otherwise. For that reason, it is not recommended to do so.
1730 Instead, make sure that each derivation declares all the inputs that it
1733 @item --disable-chroot
1734 Disable chroot builds.
1736 Using this option is not recommended since, again, it would allow build
1737 processes to gain access to undeclared dependencies. It is necessary,
1738 though, when @command{guix-daemon} is running under an unprivileged user
1741 @item --log-compression=@var{type}
1742 Compress build logs according to @var{type}, one of @code{gzip},
1743 @code{bzip2}, or @code{none}.
1745 Unless @option{--lose-logs} is used, all the build logs are kept in the
1746 @var{localstatedir}. To save space, the daemon automatically compresses
1747 them with gzip by default.
1749 @item --discover[=yes|no]
1750 Whether to discover substitute servers on the local network using mDNS
1753 This feature is still experimental. However, here are a few
1758 It might be faster/less expensive than fetching from remote servers;
1760 There are no security risks, only genuine substitutes will be used
1761 (@pxref{Substitute Authentication});
1763 An attacker advertising @command{guix publish} on your LAN cannot serve
1764 you malicious binaries, but they can learn what software you’re
1767 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1768 LAN can see what software you’re installing.
1771 It is also possible to enable or disable substitute server discovery at
1772 run-time by running:
1775 herd discover guix-daemon on
1776 herd discover guix-daemon off
1779 @item --disable-deduplication
1780 @cindex deduplication
1781 Disable automatic file ``deduplication'' in the store.
1783 By default, files added to the store are automatically ``deduplicated'':
1784 if a newly added file is identical to another one found in the store,
1785 the daemon makes the new file a hard link to the other file. This can
1786 noticeably reduce disk usage, at the expense of slightly increased
1787 input/output load at the end of a build process. This option disables
1790 @item --gc-keep-outputs[=yes|no]
1791 Tell whether the garbage collector (GC) must keep outputs of live
1795 @cindex garbage collector roots
1796 When set to @code{yes}, the GC will keep the outputs of any live
1797 derivation available in the store---the @file{.drv} files. The default
1798 is @code{no}, meaning that derivation outputs are kept only if they are
1799 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1802 @item --gc-keep-derivations[=yes|no]
1803 Tell whether the garbage collector (GC) must keep derivations
1804 corresponding to live outputs.
1806 When set to @code{yes}, as is the case by default, the GC keeps
1807 derivations---i.e., @file{.drv} files---as long as at least one of their
1808 outputs is live. This allows users to keep track of the origins of
1809 items in their store. Setting it to @code{no} saves a bit of disk
1812 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1813 liveness to flow from outputs to derivations, and setting
1814 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1815 derivations to outputs. When both are set to @code{yes}, the effect is
1816 to keep all the build prerequisites (the sources, compiler, libraries,
1817 and other build-time tools) of live objects in the store, regardless of
1818 whether these prerequisites are reachable from a GC root. This is
1819 convenient for developers since it saves rebuilds or downloads.
1821 @item --impersonate-linux-2.6
1822 On Linux-based systems, impersonate Linux 2.6. This means that the
1823 kernel's @command{uname} system call will report 2.6 as the release number.
1825 This might be helpful to build programs that (usually wrongfully) depend
1826 on the kernel version number.
1829 Do not keep build logs. By default they are kept under
1830 @file{@var{localstatedir}/guix/log}.
1832 @item --system=@var{system}
1833 Assume @var{system} as the current system type. By default it is the
1834 architecture/kernel pair found at configure time, such as
1835 @code{x86_64-linux}.
1837 @item --listen=@var{endpoint}
1838 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1839 as the file name of a Unix-domain socket if it starts with
1840 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1841 host name or host name and port to listen to. Here are a few examples:
1844 @item --listen=/gnu/var/daemon
1845 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1846 creating it if needed.
1848 @item --listen=localhost
1849 @cindex daemon, remote access
1850 @cindex remote access to the daemon
1851 @cindex daemon, cluster setup
1852 @cindex clusters, daemon setup
1853 Listen for TCP connections on the network interface corresponding to
1854 @code{localhost}, on port 44146.
1856 @item --listen=128.0.0.42:1234
1857 Listen for TCP connections on the network interface corresponding to
1858 @code{128.0.0.42}, on port 1234.
1861 This option can be repeated multiple times, in which case
1862 @command{guix-daemon} accepts connections on all the specified
1863 endpoints. Users can tell client commands what endpoint to connect to
1864 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1865 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1868 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1869 @option{--listen=@var{host}} is suitable on local networks, such as
1870 clusters, where only trusted nodes may connect to the build daemon. In
1871 other cases where remote access to the daemon is needed, we recommend
1872 using Unix-domain sockets along with SSH.
1875 When @option{--listen} is omitted, @command{guix-daemon} listens for
1876 connections on the Unix-domain socket located at
1877 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1881 @node Application Setup
1882 @section Application Setup
1884 @cindex foreign distro
1885 When using Guix on top of GNU/Linux distribution other than Guix System---a
1886 so-called @dfn{foreign distro}---a few additional steps are needed to
1887 get everything in place. Here are some of them.
1891 @anchor{locales-and-locpath}
1892 @cindex locales, when not on Guix System
1894 @vindex GUIX_LOCPATH
1895 Packages installed @i{via} Guix will not use the locale data of the
1896 host system. Instead, you must first install one of the locale packages
1897 available with Guix and then define the @env{GUIX_LOCPATH} environment
1901 $ guix install glibc-locales
1902 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1905 Note that the @code{glibc-locales} package contains data for all the
1906 locales supported by the GNU@tie{}libc and weighs in at around
1907 930@tie{}MiB@footnote{The size of the @code{glibc-locales} package is
1908 reduced down to about 213@tie{}MiB with store deduplication and further
1909 down to about 67@tie{}MiB when using a zstd-compressed Btrfs file
1910 system.}. If you only need a few locales, you can define your custom
1911 locales package via the @code{make-glibc-utf8-locales} procedure from
1912 the @code{(gnu packages base)} module. The following example defines a
1913 package containing the various Canadian UTF-8 locales known to the
1914 GNU@tie{}libc, that weighs around 14@tie{}MiB:
1917 (use-modules (gnu packages base))
1919 (define my-glibc-locales
1920 (make-glibc-utf8-locales
1922 #:locales (list "en_CA" "fr_CA" "ik_CA" "iu_CA" "shs_CA")
1923 #:name "glibc-canadian-utf8-locales"))
1926 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1927 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1928 Manual}). There are two important differences though:
1932 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1933 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1934 to make sure the programs of the foreign distro will not end up loading
1935 incompatible locale data.
1938 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1939 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1940 should your Guix profile contain a mixture of programs linked against
1941 different libc version, each libc version will only try to load locale
1942 data in the right format.
1945 This is important because the locale data format used by different libc
1946 versions may be incompatible.
1948 @subsection Name Service Switch
1950 @cindex name service switch, glibc
1951 @cindex NSS (name service switch), glibc
1952 @cindex nscd (name service caching daemon)
1953 @cindex name service caching daemon (nscd)
1954 When using Guix on a foreign distro, we @emph{strongly recommend} that
1955 the system run the GNU C library's @dfn{name service cache daemon},
1956 @command{nscd}, which should be listening on the
1957 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1958 installed with Guix may fail to look up host names or user accounts, or
1959 may even crash. The next paragraphs explain why.
1961 @cindex @file{nsswitch.conf}
1962 The GNU C library implements a @dfn{name service switch} (NSS), which is
1963 an extensible mechanism for ``name lookups'' in general: host name
1964 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1965 The GNU C Library Reference Manual}).
1967 @cindex Network information service (NIS)
1968 @cindex NIS (Network information service)
1969 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1970 lookup implementations: for example, the @code{nss-mdns} plugin allow
1971 resolution of @code{.local} host names, the @code{nis} plugin allows
1972 user account lookup using the Network information service (NIS), and so
1973 on. These extra ``lookup services'' are configured system-wide in
1974 @file{/etc/nsswitch.conf}, and all the programs running on the system
1975 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1978 When they perform a name lookup---for instance by calling the
1979 @code{getaddrinfo} function in C---applications first try to connect to
1980 the nscd; on success, nscd performs name lookups on their behalf. If
1981 the nscd is not running, then they perform the name lookup by
1982 themselves, by loading the name lookup services into their own address
1983 space and running it. These name lookup services---the
1984 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1985 the host system's C library, rather than from the C library the
1986 application is linked against (the C library coming from Guix).
1988 And this is where the problem is: if your application is linked against
1989 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1990 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1991 likely crash or have its name lookups fail unexpectedly.
1993 Running @command{nscd} on the system, among other advantages, eliminates
1994 this binary incompatibility problem because those @code{libnss_*.so}
1995 files are loaded in the @command{nscd} process, not in applications
1998 @subsection X11 Fonts
2001 The majority of graphical applications use Fontconfig to locate and load
2002 fonts and perform X11-client-side rendering. The @code{fontconfig}
2003 package in Guix looks for fonts in @file{$HOME/.guix-profile} by
2004 default. Thus, to allow graphical applications installed with Guix to
2005 display fonts, you have to install fonts with Guix as well. Essential
2006 font packages include @code{font-ghostscript}, @code{font-dejavu}, and
2007 @code{font-gnu-freefont}.
2009 @cindex @code{fc-cache}
2011 Once you have installed or removed fonts, or when you notice an
2012 application that does not find fonts, you may need to install Fontconfig
2013 and to force an update of its font cache by running:
2016 guix install fontconfig
2020 To display text written in Chinese languages, Japanese, or Korean in
2021 graphical applications, consider installing
2022 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
2023 has multiple outputs, one per language family (@pxref{Packages with
2024 Multiple Outputs}). For instance, the following command installs fonts
2025 for Chinese languages:
2028 guix install font-adobe-source-han-sans:cn
2031 @cindex @code{xterm}
2032 Older programs such as @command{xterm} do not use Fontconfig and instead
2033 rely on server-side font rendering. Such programs require to specify a
2034 full name of a font using XLFD (X Logical Font Description), like this:
2037 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
2040 To be able to use such full names for the TrueType fonts installed in
2041 your Guix profile, you need to extend the font path of the X server:
2043 @c Note: 'xset' does not accept symlinks so the trick below arranges to
2044 @c get at the real directory. See <https://bugs.gnu.org/30655>.
2046 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
2049 @cindex @code{xlsfonts}
2050 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
2051 to make sure your TrueType fonts are listed there.
2054 @subsection X.509 Certificates
2056 @cindex @code{nss-certs}
2057 The @code{nss-certs} package provides X.509 certificates, which allow
2058 programs to authenticate Web servers accessed over HTTPS.
2060 When using Guix on a foreign distro, you can install this package and
2061 define the relevant environment variables so that packages know where to
2062 look for certificates. @xref{X.509 Certificates}, for detailed
2065 @subsection Emacs Packages
2067 @cindex @code{emacs}
2068 When you install Emacs packages with Guix, the Elisp files are placed
2069 under the @file{share/emacs/site-lisp/} directory of the profile in
2070 which they are installed. The Elisp libraries are made available to
2071 Emacs through the @env{EMACSLOADPATH} environment variable, which is
2072 set when installing Emacs itself.
2074 Additionally, autoload definitions are automatically evaluated at the
2075 initialization of Emacs, by the Guix-specific
2076 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
2077 want to avoid auto-loading the Emacs packages installed with Guix, you
2078 can do so by running Emacs with the @option{--no-site-file} option
2079 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
2082 @node Upgrading Guix
2083 @section Upgrading Guix
2085 @cindex Upgrading Guix, on a foreign distro
2087 To upgrade Guix, run:
2093 @xref{Invoking guix pull}, for more information.
2095 @cindex upgrading Guix for the root user, on a foreign distro
2096 @cindex upgrading the Guix daemon, on a foreign distro
2097 @cindex @command{guix pull} for the root user, on a foreign distro
2099 On a foreign distro, you can upgrade the build daemon by running:
2106 followed by (assuming your distro uses the systemd service management
2110 systemctl restart guix-daemon.service
2113 On Guix System, upgrading the daemon is achieved by reconfiguring the
2114 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
2118 @c *********************************************************************
2119 @node System Installation
2120 @chapter System Installation
2122 @cindex installing Guix System
2123 @cindex Guix System, installation
2124 This section explains how to install Guix System
2125 on a machine. Guix, as a package manager, can
2126 also be installed on top of a running GNU/Linux system,
2127 @pxref{Installation}.
2131 @c This paragraph is for people reading this from tty2 of the
2132 @c installation image.
2133 You are reading this documentation with an Info reader. For details on
2134 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
2135 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
2136 Info}. Hit @kbd{l} afterwards to come back here.
2138 Alternatively, run @command{info info} in another tty to keep the manual
2144 * Limitations:: What you can expect.
2145 * Hardware Considerations:: Supported hardware.
2146 * USB Stick and DVD Installation:: Preparing the installation medium.
2147 * Preparing for Installation:: Networking, partitioning, etc.
2148 * Guided Graphical Installation:: Easy graphical installation.
2149 * Manual Installation:: Manual installation for wizards.
2150 * After System Installation:: When installation succeeded.
2151 * Installing Guix in a VM:: Guix System playground.
2152 * Building the Installation Image:: How this comes to be.
2156 @section Limitations
2158 We consider Guix System to be ready for a wide range of ``desktop'' and server
2159 use cases. The reliability guarantees it provides---transactional upgrades
2160 and rollbacks, reproducibility---make it a solid foundation.
2162 Nevertheless, before you proceed with the installation, be aware of the
2163 following noteworthy limitations applicable to version @value{VERSION}:
2167 More and more system services are provided (@pxref{Services}), but some
2171 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
2172 as well as a number of X11 window managers. However, KDE is currently
2176 More than a disclaimer, this is an invitation to report issues (and success
2177 stories!), and to join us in improving it. @xref{Contributing}, for more
2181 @node Hardware Considerations
2182 @section Hardware Considerations
2184 @cindex hardware support on Guix System
2185 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2186 builds around the kernel Linux-libre, which means that only hardware for
2187 which free software drivers and firmware exist is supported. Nowadays,
2188 a wide range of off-the-shelf hardware is supported on
2189 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2190 Ethernet controllers. Unfortunately, there are still areas where
2191 hardware vendors deny users control over their own computing, and such
2192 hardware is not supported on Guix System.
2194 @cindex WiFi, hardware support
2195 One of the main areas where free drivers or firmware are lacking is WiFi
2196 devices. WiFi devices known to work include those using Atheros chips
2197 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2198 driver, and those using Broadcom/AirForce chips (BCM43xx with
2199 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2200 Linux-libre driver. Free firmware exists for both and is available
2201 out-of-the-box on Guix System, as part of @code{%base-firmware}
2202 (@pxref{operating-system Reference, @code{firmware}}).
2204 @cindex RYF, Respects Your Freedom
2205 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2206 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2207 certification program for hardware products that respect your freedom
2208 and your privacy and ensure that you have control over your device. We
2209 encourage you to check the list of RYF-certified devices.
2211 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2212 web site. It contains a catalog of hardware devices with information
2213 about their support in GNU/Linux.
2216 @node USB Stick and DVD Installation
2217 @section USB Stick and DVD Installation
2219 An ISO-9660 installation image that can be written to a USB stick or
2220 burnt to a DVD can be downloaded from
2221 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso},
2222 where you can replace @code{x86_64-linux} with one of:
2226 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2229 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2232 @c start duplication of authentication part from ``Binary Installation''
2233 Make sure to download the associated @file{.sig} file and to verify the
2234 authenticity of the image against it, along these lines:
2237 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2238 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2241 If that command fails because you do not have the required public key,
2242 then run this command to import it:
2245 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2246 -qO - | gpg --import -
2250 and rerun the @code{gpg --verify} command.
2252 Take note that a warning like ``This key is not certified with a trusted
2253 signature!'' is normal.
2257 This image contains the tools necessary for an installation.
2258 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2260 @unnumberedsubsec Copying to a USB Stick
2262 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2263 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2264 copy the image with:
2267 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2271 Access to @file{/dev/sdX} usually requires root privileges.
2273 @unnumberedsubsec Burning on a DVD
2275 Insert a blank DVD into your machine, and determine
2276 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2277 copy the image with:
2280 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2283 Access to @file{/dev/srX} usually requires root privileges.
2285 @unnumberedsubsec Booting
2287 Once this is done, you should be able to reboot the system and boot from
2288 the USB stick or DVD@. The latter usually requires you to get in the
2289 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2290 In order to boot from Libreboot, switch to the command mode by pressing
2291 the @kbd{c} key and type @command{search_grub usb}.
2293 @xref{Installing Guix in a VM}, if, instead, you would like to install
2294 Guix System in a virtual machine (VM).
2297 @node Preparing for Installation
2298 @section Preparing for Installation
2300 Once you have booted, you can use the guided graphical installer, which makes
2301 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2302 if you are already familiar with GNU/Linux and if you want more control than
2303 what the graphical installer provides, you can choose the ``manual''
2304 installation process (@pxref{Manual Installation}).
2306 The graphical installer is available on TTY1. You can obtain root shells on
2307 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2308 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2309 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2310 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2311 which allows you to select text with the left mouse button and to paste it
2312 with the middle button.
2315 Installation requires access to the Internet so that any missing
2316 dependencies of your system configuration can be downloaded. See the
2317 ``Networking'' section below.
2320 @node Guided Graphical Installation
2321 @section Guided Graphical Installation
2323 The graphical installer is a text-based user interface. It will guide you,
2324 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2326 The first dialog boxes allow you to set up the system as you use it during the
2327 installation: you can choose the language, keyboard layout, and set up
2328 networking, which will be used during the installation. The image below shows
2329 the networking dialog.
2331 @image{images/installer-network,5in,, networking setup with the graphical installer}
2333 Later steps allow you to partition your hard disk, as shown in the image
2334 below, to choose whether or not to use encrypted file systems, to enter the
2335 host name and root password, and to create an additional account, among other
2338 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2340 Note that, at any time, the installer allows you to exit the current
2341 installation step and resume at a previous step, as show in the image below.
2343 @image{images/installer-resume,5in,, resuming the installation process}
2345 Once you're done, the installer produces an operating system configuration and
2346 displays it (@pxref{Using the Configuration System}). At that point you can
2347 hit ``OK'' and installation will proceed. On success, you can reboot into the
2348 new system and enjoy. @xref{After System Installation}, for what's next!
2351 @node Manual Installation
2352 @section Manual Installation
2354 This section describes how you would ``manually'' install GNU@tie{}Guix System
2355 on your machine. This option requires familiarity with GNU/Linux, with the
2356 shell, and with common administration tools. If you think this is not for
2357 you, consider using the guided graphical installer (@pxref{Guided Graphical
2360 The installation system provides root shells on TTYs 3 to 6; press
2361 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2362 many common tools needed to install the system, but is also a full-blown
2363 Guix System. This means that you can install additional packages, should you
2364 need it, using @command{guix package} (@pxref{Invoking guix package}).
2367 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2368 * Proceeding with the Installation:: Installing.
2371 @node Keyboard Layout and Networking and Partitioning
2372 @subsection Keyboard Layout, Networking, and Partitioning
2374 Before you can install the system, you may want to adjust the keyboard layout,
2375 set up networking, and partition your target hard disk. This section will
2376 guide you through this.
2378 @subsubsection Keyboard Layout
2380 @cindex keyboard layout
2381 The installation image uses the US qwerty keyboard layout. If you want
2382 to change it, you can use the @command{loadkeys} command. For example,
2383 the following command selects the Dvorak keyboard layout:
2389 See the files under @file{/run/current-system/profile/share/keymaps} for
2390 a list of available keyboard layouts. Run @command{man loadkeys} for
2393 @anchor{manual-installation-networking}
2394 @subsubsection Networking
2396 Run the following command to see what your network interfaces are called:
2403 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2409 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2410 Wired interfaces have a name starting with @samp{e}; for example, the
2411 interface corresponding to the first on-board Ethernet controller is
2412 called @samp{eno1}. Wireless interfaces have a name starting with
2413 @samp{w}, like @samp{w1p2s0}.
2416 @item Wired connection
2417 To configure a wired network run the following command, substituting
2418 @var{interface} with the name of the wired interface you want to use.
2421 ifconfig @var{interface} up
2425 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2428 ip link set @var{interface} up
2431 @item Wireless connection
2434 To configure wireless networking, you can create a configuration file
2435 for the @command{wpa_supplicant} configuration tool (its location is not
2436 important) using one of the available text editors such as
2440 nano wpa_supplicant.conf
2443 As an example, the following stanza can go to this file and will work
2444 for many wireless networks, provided you give the actual SSID and
2445 passphrase for the network you are connecting to:
2449 ssid="@var{my-ssid}"
2451 psk="the network's secret passphrase"
2455 Start the wireless service and run it in the background with the
2456 following command (substitute @var{interface} with the name of the
2457 network interface you want to use):
2460 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2463 Run @command{man wpa_supplicant} for more information.
2467 At this point, you need to acquire an IP address. On a network where IP
2468 addresses are automatically assigned @i{via} DHCP, you can run:
2471 dhclient -v @var{interface}
2474 Try to ping a server to see if networking is up and running:
2480 Setting up network access is almost always a requirement because the
2481 image does not contain all the software and tools that may be needed.
2483 @cindex proxy, during system installation
2484 If you need HTTP and HTTPS access to go through a proxy, run the
2488 herd set-http-proxy guix-daemon @var{URL}
2492 where @var{URL} is the proxy URL, for example
2493 @code{http://example.org:8118}.
2495 @cindex installing over SSH
2496 If you want to, you can continue the installation remotely by starting
2500 herd start ssh-daemon
2503 Make sure to either set a password with @command{passwd}, or configure
2504 OpenSSH public key authentication before logging in.
2506 @subsubsection Disk Partitioning
2508 Unless this has already been done, the next step is to partition, and
2509 then format the target partition(s).
2511 The installation image includes several partitioning tools, including
2512 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2513 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2514 the partition layout you want:
2520 If your disk uses the GUID Partition Table (GPT) format and you plan to
2521 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2522 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2525 @cindex EFI, installation
2526 @cindex UEFI, installation
2527 @cindex ESP, EFI system partition
2528 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2529 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2530 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2533 parted /dev/sda set 1 esp on
2537 @vindex grub-bootloader
2538 @vindex grub-efi-bootloader
2539 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2540 @file{/sys/firmware/efi} exists in the installation image, then you should
2541 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2542 Otherwise you should use the BIOS-based GRUB, known as
2543 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2547 Once you are done partitioning the target hard disk drive, you have to
2548 create a file system on the relevant partition(s)@footnote{Currently
2549 Guix System only supports ext4, btrfs, JFS, F2FS, and XFS file systems. In
2550 particular, code that reads file system UUIDs and labels only works for these
2551 file system types.}. For the ESP, if you have one and assuming it is
2552 @file{/dev/sda1}, run:
2555 mkfs.fat -F32 /dev/sda1
2558 For the root file system, ext4 is the most widely used format. Other
2559 file systems, such as Btrfs, support compression, which is reported to
2560 nicely complement file deduplication that the daemon performs
2561 independently of the file system (@pxref{Invoking guix-daemon,
2564 Preferably, assign file systems a label so that you can easily and
2565 reliably refer to them in @code{file-system} declarations (@pxref{File
2566 Systems}). This is typically done using the @code{-L} option of
2567 @command{mkfs.ext4} and related commands. So, assuming the target root
2568 partition lives at @file{/dev/sda2}, a file system with the label
2569 @code{my-root} can be created with:
2572 mkfs.ext4 -L my-root /dev/sda2
2575 @cindex encrypted disk
2576 If you are instead planning to encrypt the root partition, you can use
2577 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2578 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2579 @code{man cryptsetup}} for more information).
2582 Note that GRUB can unlock LUKS2 devices since version 2.06, but only
2583 supports the PBKDF2 key derivation function, which is not the default
2584 for @command{cryptsetup luksFormat}. You can check which key derivation
2585 function is being used by a device by running @command{cryptsetup
2586 luksDump @var{device}}, and looking for the PBKDF field of your
2590 Assuming you want to store the root partition on @file{/dev/sda2}, the
2591 command sequence to format it as a LUKS2 partition would be along these
2595 cryptsetup luksFormat --type luks2 --pbkdf pbkdf2 /dev/sda2
2596 cryptsetup open /dev/sda2 my-partition
2597 mkfs.ext4 -L my-root /dev/mapper/my-partition
2600 Once that is done, mount the target file system under @file{/mnt}
2601 with a command like (again, assuming @code{my-root} is the label of the
2605 mount LABEL=my-root /mnt
2608 Also mount any other file systems you would like to use on the target
2609 system relative to this path. If you have opted for @file{/boot/efi} as an
2610 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2611 found by @code{guix system init} afterwards.
2613 Finally, if you plan to use one or more swap partitions (@pxref{Swap
2614 Space}), make sure to initialize them with @command{mkswap}. Assuming
2615 you have one swap partition on @file{/dev/sda3}, you would run:
2622 Alternatively, you may use a swap file. For example, assuming that in
2623 the new system you want to use the file @file{/swapfile} as a swap file,
2624 you would run@footnote{This example will work for many types of file
2625 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2626 btrfs), the required steps may be different. For details, see the
2627 manual pages for @command{mkswap} and @command{swapon}.}:
2630 # This is 10 GiB of swap space. Adjust "count" to change the size.
2631 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2632 # For security, make the file readable and writable only by root.
2633 chmod 600 /mnt/swapfile
2634 mkswap /mnt/swapfile
2635 swapon /mnt/swapfile
2638 Note that if you have encrypted the root partition and created a swap
2639 file in its file system as described above, then the encryption also
2640 protects the swap file, just like any other file in that file system.
2642 @node Proceeding with the Installation
2643 @subsection Proceeding with the Installation
2645 With the target partitions ready and the target root mounted on
2646 @file{/mnt}, we're ready to go. First, run:
2649 herd start cow-store /mnt
2652 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2653 during the installation phase are written to the target disk on @file{/mnt}
2654 rather than kept in memory. This is necessary because the first phase of
2655 the @command{guix system init} command (see below) entails downloads or
2656 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2658 Next, you have to edit a file and
2659 provide the declaration of the operating system to be installed. To
2660 that end, the installation system comes with three text editors. We
2661 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2662 supports syntax highlighting and parentheses matching; other editors
2663 include mg (an Emacs clone), and
2664 nvi (a clone of the original BSD @command{vi} editor).
2665 We strongly recommend storing that file on the target root file system, say,
2666 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2667 configuration file once you have rebooted into the newly-installed system.
2669 @xref{Using the Configuration System}, for an overview of the
2670 configuration file. The example configurations discussed in that
2671 section are available under @file{/etc/configuration} in the
2672 installation image. Thus, to get started with a system configuration
2673 providing a graphical display server (a ``desktop'' system), you can run
2674 something along these lines:
2678 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2679 # nano /mnt/etc/config.scm
2682 You should pay attention to what your configuration file contains, and
2687 Make sure the @code{bootloader-configuration} form refers to the targets
2688 you want to install GRUB on. It should mention @code{grub-bootloader}
2689 if you are installing GRUB in the legacy way, or
2690 @code{grub-efi-bootloader} for newer UEFI systems. For legacy systems,
2691 the @code{targets} field contain the names of the devices, like
2692 @code{(list "/dev/sda")}; for UEFI systems it names the paths to mounted
2693 EFI partitions, like @code{(list "/boot/efi")}; do make sure the paths
2694 are currently mounted and a @code{file-system} entry is specified in
2698 Be sure that your file system labels match the value of their respective
2699 @code{device} fields in your @code{file-system} configuration, assuming
2700 your @code{file-system} configuration uses the @code{file-system-label}
2701 procedure in its @code{device} field.
2704 If there are encrypted or RAID partitions, make sure to add a
2705 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2708 Once you are done preparing the configuration file, the new system must
2709 be initialized (remember that the target root file system is mounted
2713 guix system init /mnt/etc/config.scm /mnt
2717 This copies all the necessary files and installs GRUB on
2718 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2719 more information, @pxref{Invoking guix system}. This command may trigger
2720 downloads or builds of missing packages, which can take some time.
2722 Once that command has completed---and hopefully succeeded!---you can run
2723 @command{reboot} and boot into the new system. The @code{root} password
2724 in the new system is initially empty; other users' passwords need to be
2725 initialized by running the @command{passwd} command as @code{root},
2726 unless your configuration specifies otherwise
2727 (@pxref{user-account-password, user account passwords}).
2728 @xref{After System Installation}, for what's next!
2731 @node After System Installation
2732 @section After System Installation
2734 Success, you've now booted into Guix System! From then on, you can update the
2735 system whenever you want by running, say:
2739 sudo guix system reconfigure /etc/config.scm
2743 This builds a new system generation with the latest packages and services
2744 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2745 your system includes the latest security updates (@pxref{Security Updates}).
2747 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2749 @cindex sudo vs. @command{guix pull}
2750 Note that @command{sudo guix} runs your user's @command{guix} command and
2751 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2752 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2754 The difference matters here, because @command{guix pull} updates
2755 the @command{guix} command and package definitions only for the user it is run
2756 as. This means that if you choose to use @command{guix system reconfigure} in
2757 root's login shell, you'll need to @command{guix pull} separately.
2760 Now, @pxref{Getting Started}, and
2761 join us on @code{#guix} on the Libera Chat IRC network or on
2762 @email{guix-devel@@gnu.org} to share your experience!
2765 @node Installing Guix in a VM
2766 @section Installing Guix in a Virtual Machine
2768 @cindex virtual machine, Guix System installation
2769 @cindex virtual private server (VPS)
2770 @cindex VPS (virtual private server)
2771 If you'd like to install Guix System in a virtual machine (VM) or on a
2772 virtual private server (VPS) rather than on your beloved machine, this
2775 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2776 disk image, follow these steps:
2780 First, retrieve and decompress the Guix system installation image as
2781 described previously (@pxref{USB Stick and DVD Installation}).
2784 Create a disk image that will hold the installed system. To make a
2785 qcow2-formatted disk image, use the @command{qemu-img} command:
2788 qemu-img create -f qcow2 guix-system.img 50G
2791 The resulting file will be much smaller than 50 GB (typically less than
2792 1 MB), but it will grow as the virtualized storage device is filled up.
2795 Boot the USB installation image in an VM:
2798 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2799 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2800 -drive file=guix-system.img \
2801 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2804 @code{-enable-kvm} is optional, but significantly improves performance,
2805 @pxref{Running Guix in a VM}.
2808 You're now root in the VM, proceed with the installation process.
2809 @xref{Preparing for Installation}, and follow the instructions.
2812 Once installation is complete, you can boot the system that's on your
2813 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2816 @node Building the Installation Image
2817 @section Building the Installation Image
2819 @cindex installation image
2820 The installation image described above was built using the @command{guix
2821 system} command, specifically:
2824 guix system image -t iso9660 gnu/system/install.scm
2827 Have a look at @file{gnu/system/install.scm} in the source tree,
2828 and see also @ref{Invoking guix system} for more information
2829 about the installation image.
2831 @section Building the Installation Image for ARM Boards
2833 Many ARM boards require a specific variant of the
2834 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2836 If you build a disk image and the bootloader is not available otherwise
2837 (on another boot drive etc), it's advisable to build an image that
2838 includes the bootloader, specifically:
2841 guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2844 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2845 board, a list of possible boards will be printed.
2847 @c *********************************************************************
2848 @cindex troubleshooting, guix system
2849 @cindex guix system troubleshooting
2850 @node System Troubleshooting Tips
2851 @chapter System Troubleshooting Tips
2853 Guix System allows rebooting into a previous generation should the last
2854 one be malfunctioning, which makes it quite robust against being broken
2855 irreversibly. This feature depends on GRUB being correctly functioning
2856 though, which means that if for whatever reasons your GRUB installation
2857 becomes corrupted during a system reconfiguration, you may not be able
2858 to easily boot into a previous generation. A technique that can be used
2859 in this case is to @i{chroot} into your broken system and reconfigure it
2860 from there. Such technique is explained below.
2862 @cindex chroot, guix system
2863 @cindex chrooting, guix system
2864 @cindex repairing GRUB, via chroot
2865 @node Chrooting into an existing system
2866 @section Chrooting into an existing system
2868 This section details how to @i{chroot} to an already installed Guix
2869 System with the aim of reconfiguring it, for example to fix a broken
2870 GRUB installation. The process is similar to how it would be done on
2871 other GNU/Linux systems, but there are some Guix System particularities
2872 such as the daemon and profiles that make it worthy of explaining here.
2876 Obtain a bootable image of Guix System. It is recommended the latest
2877 development snapshot so the kernel and the tools used are at least as as
2878 new as those of your installed system; it can be retrieved from the
2879 @url{https://ci.guix.gnu.org/search/latest/ISO-9660?query=spec:images+status:success+system:x86_64-linux+image.iso,
2880 https://ci.guix.gnu.org} URL. Follow the @pxref{USB Stick and DVD
2881 Installation} section for copying it to a bootable media.
2884 Boot the image, and proceed with the graphical text-based installer
2885 until your network is configured. Alternatively, you could configure
2886 the network manually by following the
2887 @ref{manual-installation-networking} section. If you get the error
2888 @samp{RTNETLINK answers: Operation not possible due to RF-kill}, try
2889 @samp{rfkill list} followed by @samp{rfkill unblock 0}, where @samp{0}
2890 is your device identifier (ID).
2893 Switch to a virtual console (tty) if you haven't already by pressing
2894 simultaneously the @kbd{Control + Alt + F4} keys. Mount your file
2895 system at @file{/mnt}. Assuming your root partition is
2896 @file{/dev/sda2}, you would do:
2899 mount /dev/sda2 /mnt
2903 Mount special block devices and Linux-specific directories:
2906 mount --bind /proc /mnt/proc
2907 mount --bind /sys /mnt/sys
2908 mount --bind /dev /mnt/dev
2911 If your system is EFI-based, you must also mount the ESP partition.
2912 Assuming it is @file{/dev/sda1}, you can do so with:
2915 mount /dev/sda1 /mnt/boot/efi
2919 Enter your system via chroot:
2926 Source your @var{user} profile to setup the environment, where
2927 @var{user} is the user name used for the Guix System you are attempting
2931 source /home/@var{user}/.guix-profile/etc/profile
2934 To ensure you are working with the Guix revision you normally would as
2935 your normal user, also source your current Guix profile:
2938 source /home/@var{user}/.config/guix/current/etc/profile
2942 Start a minimal @command{guix-daemon} in the background:
2945 guix-daemon --build-users-group=guixbuild --disable-chroot &
2949 Edit your Guix System configuration if needed, then reconfigure with:
2952 guix system reconfigure your-config.scm
2956 Finally, you should be good to reboot the system to test your fix.
2960 @c *********************************************************************
2961 @node Getting Started
2962 @chapter Getting Started
2964 Presumably, you've reached this section because either you have
2965 installed Guix on top of another distribution (@pxref{Installation}), or
2966 you've installed the standalone Guix System (@pxref{System
2967 Installation}). It's time for you to get started using Guix and this
2968 section aims to help you do that and give you a feel of what it's like.
2970 Guix is about installing software, so probably the first thing you'll
2971 want to do is to actually look for software. Let's say you're looking
2972 for a text editor, you can run:
2975 guix search text editor
2978 This command shows you a number of matching @dfn{packages}, each time
2979 showing the package's name, version, a description, and additional info.
2980 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2981 you can go ahead and install it (run this command as a regular user,
2982 @emph{no need for root privileges}!):
2989 You've installed your first package, congrats! The package is now
2990 visible in your default @dfn{profile}, @file{$HOME/.guix-profile}---a
2991 profile is a directory containing installed packages.
2992 In the process, you've
2993 probably noticed that Guix downloaded pre-built binaries; or, if you
2994 explicitly chose to @emph{not} use pre-built binaries, then probably
2995 Guix is still building software (@pxref{Substitutes}, for more info).
2997 Unless you're using Guix System, the @command{guix install} command must
2998 have printed this hint:
3001 hint: Consider setting the necessary environment variables by running:
3003 GUIX_PROFILE="$HOME/.guix-profile"
3004 . "$GUIX_PROFILE/etc/profile"
3006 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
3009 Indeed, you must now tell your shell where @command{emacs} and other
3010 programs installed with Guix are to be found. Pasting the two lines
3011 above will do just that: it will add
3012 @code{$HOME/.guix-profile/bin}---which is where the installed package
3013 is---to the @code{PATH} environment variable. You can paste these two
3014 lines in your shell so they take effect right away, but more importantly
3015 you should add them to @file{~/.bash_profile} (or equivalent file if you
3016 do not use Bash) so that environment variables are set next time you
3017 spawn a shell. You only need to do this once and other search paths
3018 environment variables will be taken care of similarly---e.g., if you
3019 eventually install @code{python} and Python libraries,
3020 @env{GUIX_PYTHONPATH} will be defined.
3022 You can go on installing packages at your will. To list installed
3026 guix package --list-installed
3029 To remove a package, you would unsurprisingly run @command{guix remove}.
3030 A distinguishing feature is the ability to @dfn{roll back} any operation
3031 you made---installation, removal, upgrade---by simply typing:
3034 guix package --roll-back
3037 This is because each operation is in fact a @dfn{transaction} that
3038 creates a new @dfn{generation}. These generations and the difference
3039 between them can be displayed by running:
3042 guix package --list-generations
3045 Now you know the basics of package management!
3047 @quotation Going further
3048 @xref{Package Management}, for more about package management. You may
3049 like @dfn{declarative} package management with @command{guix package
3050 --manifest}, managing separate @dfn{profiles} with @option{--profile},
3051 deleting old generations, collecting garbage, and other nifty features
3052 that will come in handy as you become more familiar with Guix. If you
3053 are a developer, @pxref{Development} for additional tools. And if
3054 you're curious, @pxref{Features}, to peek under the hood.
3057 Once you've installed a set of packages, you will want to periodically
3058 @emph{upgrade} them to the latest and greatest version. To do that, you
3059 will first pull the latest revision of Guix and its package collection:
3065 The end result is a new @command{guix} command, under
3066 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
3067 first time you run @command{guix pull}, be sure to follow the hint that
3068 the command prints and, similar to what we saw above, paste these two
3069 lines in your terminal and @file{.bash_profile}:
3072 GUIX_PROFILE="$HOME/.config/guix/current"
3073 . "$GUIX_PROFILE/etc/profile"
3077 You must also instruct your shell to point to this new @command{guix}:
3083 At this point, you're running a brand new Guix. You can thus go ahead
3084 and actually upgrade all the packages you previously installed:
3090 As you run this command, you will see that binaries are downloaded (or
3091 perhaps some packages are built), and eventually you end up with the
3092 upgraded packages. Should one of these upgraded packages not be to your
3093 liking, remember you can always roll back!
3095 You can display the exact revision of Guix you're currently using by
3102 The information it displays is @emph{all it takes to reproduce the exact
3103 same Guix}, be it at a different point in time or on a different
3106 @quotation Going further
3107 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
3108 how to specify additional @dfn{channels} to pull packages from, how to
3109 replicate Guix, and more. You may also find @command{time-machine}
3110 handy (@pxref{Invoking guix time-machine}).
3113 If you installed Guix System, one of the first things you'll want to do
3114 is to upgrade your system. Once you've run @command{guix pull} to get
3115 the latest Guix, you can upgrade the system like this:
3118 sudo guix system reconfigure /etc/config.scm
3121 Upon completion, the system runs the latest versions of its software
3122 packages. When you eventually reboot, you'll notice a sub-menu in the
3123 bootloader that reads ``Old system generations'': it's what allows you
3124 to boot @emph{an older generation of your system}, should the latest
3125 generation be ``broken'' or otherwise unsatisfying. Just like for
3126 packages, you can always @emph{roll back} to a previous generation
3127 @emph{of the whole system}:
3130 sudo guix system roll-back
3133 There are many things you'll probably want to tweak on your system:
3134 adding new user accounts, adding new system services, fiddling with the
3135 configuration of those services, etc. The system configuration is
3136 @emph{entirely} described in the @file{/etc/config.scm} file.
3137 @xref{Using the Configuration System}, to learn how to change it.
3139 Now you know enough to get started!
3141 @quotation Resources
3142 The rest of this manual provides a reference for all things Guix. Here
3143 are some additional resources you may find useful:
3147 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
3148 ``how-to'' style of recipes for a variety of applications.
3151 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
3152 Card} lists in two pages most of the commands and options you'll ever
3156 The web site contains @uref{https://guix.gnu.org/en/videos/,
3157 instructional videos} covering topics such as everyday use of Guix, how
3158 to get help, and how to become a contributor.
3161 @xref{Documentation}, to learn how to access documentation on your
3165 We hope you will enjoy Guix as much as the community enjoys building it!
3168 @c *********************************************************************
3169 @node Package Management
3170 @chapter Package Management
3173 The purpose of GNU Guix is to allow users to easily install, upgrade, and
3174 remove software packages, without having to know about their build
3175 procedures or dependencies. Guix also goes beyond this obvious set of
3178 This chapter describes the main features of Guix, as well as the
3179 package management tools it provides. Along with the command-line
3180 interface described below (@pxref{Invoking guix package, @code{guix
3181 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
3182 emacs-guix, The Emacs-Guix Reference Manual}), after installing
3183 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
3187 guix install emacs-guix
3191 * Features:: How Guix will make your life brighter.
3192 * Invoking guix package:: Package installation, removal, etc.
3193 * Substitutes:: Downloading pre-built binaries.
3194 * Packages with Multiple Outputs:: Single source package, multiple outputs.
3195 * Invoking guix gc:: Running the garbage collector.
3196 * Invoking guix pull:: Fetching the latest Guix and distribution.
3197 * Invoking guix time-machine:: Running an older revision of Guix.
3198 * Inferiors:: Interacting with another revision of Guix.
3199 * Invoking guix describe:: Display information about your Guix revision.
3200 * Invoking guix archive:: Exporting and importing store files.
3206 Here we assume you've already made your first steps with Guix
3207 (@pxref{Getting Started}) and would like to get an overview about what's
3208 going on under the hood.
3210 When using Guix, each package ends up in the @dfn{package store}, in its
3211 own directory---something that resembles
3212 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
3214 Instead of referring to these directories, users have their own
3215 @dfn{profile}, which points to the packages that they actually want to
3216 use. These profiles are stored within each user's home directory, at
3217 @code{$HOME/.guix-profile}.
3219 For example, @code{alice} installs GCC 4.7.2. As a result,
3220 @file{/home/alice/.guix-profile/bin/gcc} points to
3221 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
3222 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
3223 simply continues to point to
3224 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
3225 coexist on the same system without any interference.
3227 The @command{guix package} command is the central tool to manage
3228 packages (@pxref{Invoking guix package}). It operates on the per-user
3229 profiles, and can be used @emph{with normal user privileges}.
3231 @cindex transactions
3232 The command provides the obvious install, remove, and upgrade
3233 operations. Each invocation is actually a @emph{transaction}: either
3234 the specified operation succeeds, or nothing happens. Thus, if the
3235 @command{guix package} process is terminated during the transaction,
3236 or if a power outage occurs during the transaction, then the user's
3237 profile remains in its previous state, and remains usable.
3239 In addition, any package transaction may be @emph{rolled back}. So, if,
3240 for example, an upgrade installs a new version of a package that turns
3241 out to have a serious bug, users may roll back to the previous instance
3242 of their profile, which was known to work well. Similarly, the global
3243 system configuration on Guix is subject to
3244 transactional upgrades and roll-back
3245 (@pxref{Using the Configuration System}).
3247 All packages in the package store may be @emph{garbage-collected}.
3248 Guix can determine which packages are still referenced by user
3249 profiles, and remove those that are provably no longer referenced
3250 (@pxref{Invoking guix gc}). Users may also explicitly remove old
3251 generations of their profile so that the packages they refer to can be
3254 @cindex reproducibility
3255 @cindex reproducible builds
3256 Guix takes a @dfn{purely functional} approach to package
3257 management, as described in the introduction (@pxref{Introduction}).
3258 Each @file{/gnu/store} package directory name contains a hash of all the
3259 inputs that were used to build that package---compiler, libraries, build
3260 scripts, etc. This direct correspondence allows users to make sure a
3261 given package installation matches the current state of their
3262 distribution. It also helps maximize @dfn{build reproducibility}:
3263 thanks to the isolated build environments that are used, a given build
3264 is likely to yield bit-identical files when performed on different
3265 machines (@pxref{Invoking guix-daemon, container}).
3268 This foundation allows Guix to support @dfn{transparent binary/source
3269 deployment}. When a pre-built binary for a @file{/gnu/store} item is
3270 available from an external source---a @dfn{substitute}, Guix just
3271 downloads it and unpacks it;
3272 otherwise, it builds the package from source, locally
3273 (@pxref{Substitutes}). Because build results are usually bit-for-bit
3274 reproducible, users do not have to trust servers that provide
3275 substitutes: they can force a local build and @emph{challenge} providers
3276 (@pxref{Invoking guix challenge}).
3278 Control over the build environment is a feature that is also useful for
3279 developers. The @command{guix shell} command allows developers of
3280 a package to quickly set up the right development environment for their
3281 package, without having to manually install the dependencies of the
3282 package into their profile (@pxref{Invoking guix shell}).
3284 @cindex replication, of software environments
3285 @cindex provenance tracking, of software artifacts
3286 All of Guix and its package definitions is version-controlled, and
3287 @command{guix pull} allows you to ``travel in time'' on the history of Guix
3288 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
3289 Guix instance on a different machine or at a later point in time, which in
3290 turn allows you to @emph{replicate complete software environments}, while
3291 retaining precise @dfn{provenance tracking} of the software.
3293 @node Invoking guix package
3294 @section Invoking @command{guix package}
3296 @cindex installing packages
3297 @cindex removing packages
3298 @cindex package installation
3299 @cindex package removal
3301 The @command{guix package} command is the tool that allows users to
3302 install, upgrade, and remove packages, as well as rolling back to
3303 previous configurations. These operations work on a user
3304 @dfn{profile}---a directory of installed packages. Each user has a
3305 default profile in @file{$HOME/.guix-profile}.
3306 The command operates only on the user's own profile,
3307 and works with normal user privileges (@pxref{Features}). Its syntax
3311 guix package @var{options}
3314 @cindex transactions
3315 Primarily, @var{options} specifies the operations to be performed during
3316 the transaction. Upon completion, a new profile is created, but
3317 previous @dfn{generations} of the profile remain available, should the user
3320 For example, to remove @code{lua} and install @code{guile} and
3321 @code{guile-cairo} in a single transaction:
3324 guix package -r lua -i guile guile-cairo
3327 @cindex aliases, for @command{guix package}
3328 For your convenience, we also provide the following aliases:
3332 @command{guix search} is an alias for @command{guix package -s},
3334 @command{guix install} is an alias for @command{guix package -i},
3336 @command{guix remove} is an alias for @command{guix package -r},
3338 @command{guix upgrade} is an alias for @command{guix package -u},
3340 and @command{guix show} is an alias for @command{guix package --show=}.
3343 These aliases are less expressive than @command{guix package} and provide
3344 fewer options, so in some cases you'll probably want to use @command{guix
3347 @command{guix package} also supports a @dfn{declarative approach}
3348 whereby the user specifies the exact set of packages to be available and
3349 passes it @i{via} the @option{--manifest} option
3350 (@pxref{profile-manifest, @option{--manifest}}).
3353 For each user, a symlink to the user's default profile is automatically
3354 created in @file{$HOME/.guix-profile}. This symlink always points to the
3355 current generation of the user's default profile. Thus, users can add
3356 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3357 variable, and so on.
3358 @cindex search paths
3359 If you are not using Guix System, consider adding the
3360 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3361 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3362 shells get all the right environment variable definitions:
3365 GUIX_PROFILE="$HOME/.guix-profile" ; \
3366 source "$GUIX_PROFILE/etc/profile"
3369 In a multi-user setup, user profiles are stored in a place registered as
3370 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3371 to (@pxref{Invoking guix gc}). That directory is normally
3372 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3373 @var{localstatedir} is the value passed to @code{configure} as
3374 @option{--localstatedir}, and @var{user} is the user name. The
3375 @file{per-user} directory is created when @command{guix-daemon} is
3376 started, and the @var{user} sub-directory is created by @command{guix
3379 The @var{options} can be among the following:
3383 @item --install=@var{package} @dots{}
3384 @itemx -i @var{package} @dots{}
3385 Install the specified @var{package}s.
3387 Each @var{package} may specify either a simple package name, such as
3388 @code{guile}, or a package name followed by an at-sign and version number,
3389 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3390 case, the newest version prefixed by @code{1.8} is selected).
3392 If no version number is specified, the
3393 newest available version will be selected. In addition, @var{package}
3394 may contain a colon, followed by the name of one of the outputs of the
3395 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3396 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3397 name (and optionally version) are searched for among the GNU
3398 distribution modules (@pxref{Package Modules}).
3400 @cindex propagated inputs
3401 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3402 that automatically get installed along with the required package
3403 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3404 @code{package} objects}, for information about propagated inputs in
3405 package definitions).
3407 @anchor{package-cmd-propagated-inputs}
3408 An example is the GNU MPC library: its C header files refer to those of
3409 the GNU MPFR library, which in turn refer to those of the GMP library.
3410 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3411 in the profile; removing MPC also removes MPFR and GMP---unless they had
3412 also been explicitly installed by the user.
3414 Besides, packages sometimes rely on the definition of environment
3415 variables for their search paths (see explanation of
3416 @option{--search-paths} below). Any missing or possibly incorrect
3417 environment variable definitions are reported here.
3419 @item --install-from-expression=@var{exp}
3421 Install the package @var{exp} evaluates to.
3423 @var{exp} must be a Scheme expression that evaluates to a
3424 @code{<package>} object. This option is notably useful to disambiguate
3425 between same-named variants of a package, with expressions such as
3426 @code{(@@ (gnu packages base) guile-final)}.
3428 Note that this option installs the first output of the specified
3429 package, which may be insufficient when needing a specific output of a
3430 multiple-output package.
3432 @item --install-from-file=@var{file}
3433 @itemx -f @var{file}
3434 Install the package that the code within @var{file} evaluates to.
3436 As an example, @var{file} might contain a definition like this
3437 (@pxref{Defining Packages}):
3440 @include package-hello.scm
3443 Developers may find it useful to include such a @file{guix.scm} file
3444 in the root of their project source tree that can be used to test
3445 development snapshots and create reproducible development environments
3446 (@pxref{Invoking guix shell}).
3448 The @var{file} may also contain a JSON representation of one or more
3449 package definitions. Running @code{guix package -f} on
3450 @file{hello.json} with the following contents would result in installing
3451 the package @code{greeter} after building @code{myhello}:
3454 @verbatiminclude package-hello.json
3457 @item --remove=@var{package} @dots{}
3458 @itemx -r @var{package} @dots{}
3459 Remove the specified @var{package}s.
3461 As for @option{--install}, each @var{package} may specify a version number
3462 and/or output name in addition to the package name. For instance,
3463 @samp{-r glibc:debug} would remove the @code{debug} output of
3466 @item --upgrade[=@var{regexp} @dots{}]
3467 @itemx -u [@var{regexp} @dots{}]
3468 @cindex upgrading packages
3469 Upgrade all the installed packages. If one or more @var{regexp}s are
3470 specified, upgrade only installed packages whose name matches a
3471 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3473 Note that this upgrades package to the latest version of packages found
3474 in the distribution currently installed. To update your distribution,
3475 you should regularly run @command{guix pull} (@pxref{Invoking guix
3478 @cindex package transformations, upgrades
3479 When upgrading, package transformations that were originally applied
3480 when creating the profile are automatically re-applied (@pxref{Package
3481 Transformation Options}). For example, assume you first installed Emacs
3482 from the tip of its development branch with:
3485 guix install emacs-next --with-branch=emacs-next=master
3488 Next time you run @command{guix upgrade}, Guix will again pull the tip
3489 of the Emacs development branch and build @code{emacs-next} from that
3492 Note that transformation options such as @option{--with-branch} and
3493 @option{--with-source} depend on external state; it is up to you to
3494 ensure that they work as expected. You can also discard a
3495 transformations that apply to a package by running:
3498 guix install @var{package}
3501 @item --do-not-upgrade[=@var{regexp} @dots{}]
3502 When used together with the @option{--upgrade} option, do @emph{not}
3503 upgrade any packages whose name matches a @var{regexp}. For example, to
3504 upgrade all packages in the current profile except those containing the
3505 substring ``emacs'':
3508 $ guix package --upgrade . --do-not-upgrade emacs
3511 @item @anchor{profile-manifest}--manifest=@var{file}
3512 @itemx -m @var{file}
3513 @cindex profile declaration
3514 @cindex profile manifest
3515 Create a new generation of the profile from the manifest object
3516 returned by the Scheme code in @var{file}. This option can be repeated
3517 several times, in which case the manifests are concatenated.
3519 This allows you to @emph{declare} the profile's contents rather than
3520 constructing it through a sequence of @option{--install} and similar
3521 commands. The advantage is that @var{file} can be put under version
3522 control, copied to different machines to reproduce the same profile, and
3525 @var{file} must return a @dfn{manifest} object, which is roughly a list
3528 @findex packages->manifest
3530 (use-package-modules guile emacs)
3535 ;; Use a specific package output.
3536 (list guile-2.0 "debug")))
3539 @xref{Writing Manifests}, for information on how to write a manifest.
3540 @xref{export-manifest, @option{--export-manifest}}, to learn how to
3541 obtain a manifest file from an existing profile.
3544 @cindex rolling back
3545 @cindex undoing transactions
3546 @cindex transactions, undoing
3547 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3548 the last transaction.
3550 When combined with options such as @option{--install}, roll back occurs
3551 before any other actions.
3553 When rolling back from the first generation that actually contains
3554 installed packages, the profile is made to point to the @dfn{zeroth
3555 generation}, which contains no files apart from its own metadata.
3557 After having rolled back, installing, removing, or upgrading packages
3558 overwrites previous future generations. Thus, the history of the
3559 generations in a profile is always linear.
3561 @item --switch-generation=@var{pattern}
3562 @itemx -S @var{pattern}
3564 Switch to a particular generation defined by @var{pattern}.
3566 @var{pattern} may be either a generation number or a number prefixed
3567 with ``+'' or ``-''. The latter means: move forward/backward by a
3568 specified number of generations. For example, if you want to return to
3569 the latest generation after @option{--roll-back}, use
3570 @option{--switch-generation=+1}.
3572 The difference between @option{--roll-back} and
3573 @option{--switch-generation=-1} is that @option{--switch-generation} will
3574 not make a zeroth generation, so if a specified generation does not
3575 exist, the current generation will not be changed.
3577 @item --search-paths[=@var{kind}]
3578 @cindex search paths
3579 Report environment variable definitions, in Bash syntax, that may be
3580 needed in order to use the set of installed packages. These environment
3581 variables are used to specify @dfn{search paths} for files used by some
3582 of the installed packages.
3584 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3585 environment variables to be defined so it can look for headers and
3586 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3587 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3588 library are installed in the profile, then @option{--search-paths} will
3589 suggest setting these variables to @file{@var{profile}/include} and
3590 @file{@var{profile}/lib}, respectively (@pxref{Search Paths}, for info
3591 on search path specifications associated with packages.)
3593 The typical use case is to define these environment variables in the
3597 $ eval $(guix package --search-paths)
3600 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3601 meaning that the returned environment variable definitions will either
3602 be exact settings, or prefixes or suffixes of the current value of these
3603 variables. When omitted, @var{kind} defaults to @code{exact}.
3605 This option can also be used to compute the @emph{combined} search paths
3606 of several profiles. Consider this example:
3609 $ guix package -p foo -i guile
3610 $ guix package -p bar -i guile-json
3611 $ guix package -p foo -p bar --search-paths
3614 The last command above reports about the @env{GUILE_LOAD_PATH}
3615 variable, even though, taken individually, neither @file{foo} nor
3616 @file{bar} would lead to that recommendation.
3619 @cindex profile, choosing
3620 @item --profile=@var{profile}
3621 @itemx -p @var{profile}
3622 Use @var{profile} instead of the user's default profile.
3624 @var{profile} must be the name of a file that will be created upon
3625 completion. Concretely, @var{profile} will be a mere symbolic link
3626 (``symlink'') pointing to the actual profile where packages are
3630 $ guix install hello -p ~/code/my-profile
3632 $ ~/code/my-profile/bin/hello
3636 All it takes to get rid of the profile is to remove this symlink and its
3637 siblings that point to specific generations:
3640 $ rm ~/code/my-profile ~/code/my-profile-*-link
3643 @item --list-profiles
3644 List all the user's profiles:
3647 $ guix package --list-profiles
3648 /home/charlie/.guix-profile
3649 /home/charlie/code/my-profile
3650 /home/charlie/code/devel-profile
3651 /home/charlie/tmp/test
3654 When running as root, list all the profiles of all the users.
3656 @cindex collisions, in a profile
3657 @cindex colliding packages in profiles
3658 @cindex profile collisions
3659 @item --allow-collisions
3660 Allow colliding packages in the new profile. Use at your own risk!
3662 By default, @command{guix package} reports as an error @dfn{collisions}
3663 in the profile. Collisions happen when two or more different versions
3664 or variants of a given package end up in the profile.
3667 Use the bootstrap Guile to build the profile. This option is only
3668 useful to distribution developers.
3672 In addition to these actions, @command{guix package} supports the
3673 following options to query the current state of a profile, or the
3674 availability of packages:
3678 @item --search=@var{regexp}
3679 @itemx -s @var{regexp}
3680 @anchor{guix-search}
3681 @cindex searching for packages
3682 List the available packages whose name, synopsis, or description matches
3683 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3684 Print all the metadata of matching packages in
3685 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3686 GNU recutils manual}).
3688 This allows specific fields to be extracted using the @command{recsel}
3689 command, for instance:
3692 $ guix package -s malloc | recsel -p name,version,relevance
3706 Similarly, to show the name of all the packages available under the
3707 terms of the GNU@tie{}LGPL version 3:
3710 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3717 It is also possible to refine search results using several @code{-s} flags to
3718 @command{guix package}, or several arguments to @command{guix search}. For
3719 example, the following command returns a list of board games (this time using
3720 the @command{guix search} alias):
3723 $ guix search '\<board\>' game | recsel -p name
3728 If we were to omit @code{-s game}, we would also get software packages
3729 that deal with printed circuit boards; removing the angle brackets
3730 around @code{board} would further add packages that have to do with
3733 And now for a more elaborate example. The following command searches
3734 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3735 libraries, and prints the name and synopsis of the matching packages:
3738 $ guix search crypto library | \
3739 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3743 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3744 information on @dfn{selection expressions} for @code{recsel -e}.
3746 @item --show=@var{package}
3747 Show details about @var{package}, taken from the list of available packages, in
3748 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3752 $ guix package --show=guile | recsel -p name,version
3764 You may also specify the full name of a package to only get details about a
3765 specific version of it (this time using the @command{guix show} alias):
3767 $ guix show guile@@3.0.5 | recsel -p name,version
3772 @item --list-installed[=@var{regexp}]
3773 @itemx -I [@var{regexp}]
3774 List the currently installed packages in the specified profile, with the
3775 most recently installed packages shown last. When @var{regexp} is
3776 specified, list only installed packages whose name matches @var{regexp}.
3778 For each installed package, print the following items, separated by
3779 tabs: the package name, its version string, the part of the package that
3780 is installed (for instance, @code{out} for the default output,
3781 @code{include} for its headers, etc.), and the path of this package in
3784 @item --list-available[=@var{regexp}]
3785 @itemx -A [@var{regexp}]
3786 List packages currently available in the distribution for this system
3787 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3788 available packages whose name matches @var{regexp}.
3790 For each package, print the following items separated by tabs: its name,
3791 its version string, the parts of the package (@pxref{Packages with
3792 Multiple Outputs}), and the source location of its definition.
3794 @item --list-generations[=@var{pattern}]
3795 @itemx -l [@var{pattern}]
3797 Return a list of generations along with their creation dates; for each
3798 generation, show the installed packages, with the most recently
3799 installed packages shown last. Note that the zeroth generation is never
3802 For each installed package, print the following items, separated by
3803 tabs: the name of a package, its version string, the part of the package
3804 that is installed (@pxref{Packages with Multiple Outputs}), and the
3805 location of this package in the store.
3807 When @var{pattern} is used, the command returns only matching
3808 generations. Valid patterns include:
3811 @item @emph{Integers and comma-separated integers}. Both patterns denote
3812 generation numbers. For instance, @option{--list-generations=1} returns
3815 And @option{--list-generations=1,8,2} outputs three generations in the
3816 specified order. Neither spaces nor trailing commas are allowed.
3818 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3819 specified generations and everything in between. Note that the start of
3820 a range must be smaller than its end.
3822 It is also possible to omit the endpoint. For example,
3823 @option{--list-generations=2..}, returns all generations starting from the
3826 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3827 or months by passing an integer along with the first letter of the
3828 duration. For example, @option{--list-generations=20d} lists generations
3829 that are up to 20 days old.
3832 @item --delete-generations[=@var{pattern}]
3833 @itemx -d [@var{pattern}]
3834 When @var{pattern} is omitted, delete all generations except the current
3837 This command accepts the same patterns as @option{--list-generations}.
3838 When @var{pattern} is specified, delete the matching generations. When
3839 @var{pattern} specifies a duration, generations @emph{older} than the
3840 specified duration match. For instance, @option{--delete-generations=1m}
3841 deletes generations that are more than one month old.
3843 If the current generation matches, it is @emph{not} deleted. Also, the
3844 zeroth generation is never deleted.
3846 Note that deleting generations prevents rolling back to them.
3847 Consequently, this command must be used with care.
3849 @cindex manifest, exporting
3850 @anchor{export-manifest}
3851 @item --export-manifest
3852 Write to standard output a manifest suitable for @option{--manifest}
3853 corresponding to the chosen profile(s).
3855 This option is meant to help you migrate from the ``imperative''
3856 operating mode---running @command{guix install}, @command{guix upgrade},
3857 etc.---to the declarative mode that @option{--manifest} offers.
3859 Be aware that the resulting manifest @emph{approximates} what your
3860 profile actually contains; for instance, depending on how your profile
3861 was created, it can refer to packages or package versions that are not
3862 exactly what you specified.
3864 Keep in mind that a manifest is purely symbolic: it only contains
3865 package names and possibly versions, and their meaning varies over time.
3866 If you wish to ``pin'' channels to the revisions that were used to build
3867 the profile(s), see @option{--export-channels} below.
3869 @cindex pinning, channel revisions of a profile
3870 @item --export-channels
3871 Write to standard output the list of channels used by the chosen
3872 profile(s), in a format suitable for @command{guix pull --channels} or
3873 @command{guix time-machine --channels} (@pxref{Channels}).
3875 Together with @option{--export-manifest}, this option provides
3876 information allowing you to replicate the current profile
3877 (@pxref{Replicating Guix}).
3879 However, note that the output of this command @emph{approximates} what
3880 was actually used to build this profile. In particular, a single
3881 profile might have been built from several different revisions of the
3882 same channel. In that case, @option{--export-manifest} chooses the last
3883 one and writes the list of other revisions in a comment. If you really
3884 need to pick packages from different channel revisions, you can use
3885 inferiors in your manifest to do so (@pxref{Inferiors}).
3887 Together with @option{--export-manifest}, this is a good starting point
3888 if you are willing to migrate from the ``imperative'' model to the fully
3889 declarative model consisting of a manifest file along with a channels
3890 file pinning the exact channel revision(s) you want.
3893 Finally, since @command{guix package} may actually start build
3894 processes, it supports all the common build options (@pxref{Common Build
3895 Options}). It also supports package transformation options, such as
3896 @option{--with-source}, and preserves them across upgrades
3897 (@pxref{Package Transformation Options}).
3900 @section Substitutes
3903 @cindex pre-built binaries
3904 Guix supports transparent source/binary deployment, which means that it
3905 can either build things locally, or download pre-built items from a
3906 server, or both. We call these pre-built items @dfn{substitutes}---they
3907 are substitutes for local build results. In many cases, downloading a
3908 substitute is much faster than building things locally.
3910 Substitutes can be anything resulting from a derivation build
3911 (@pxref{Derivations}). Of course, in the common case, they are
3912 pre-built package binaries, but source tarballs, for instance, which
3913 also result from derivation builds, can be available as substitutes.
3916 * Official Substitute Servers:: One particular source of substitutes.
3917 * Substitute Server Authorization:: How to enable or disable substitutes.
3918 * Getting Substitutes from Other Servers:: Substitute diversity.
3919 * Substitute Authentication:: How Guix verifies substitutes.
3920 * Proxy Settings:: How to get substitutes via proxy.
3921 * Substitution Failure:: What happens when substitution fails.
3922 * On Trusting Binaries:: How can you trust that binary blob?
3925 @node Official Substitute Servers
3926 @subsection Official Substitute Servers
3929 @code{@value{SUBSTITUTE-SERVER-1}} and
3930 @code{@value{SUBSTITUTE-SERVER-2}} are both front-ends to official build
3931 farms that build packages from Guix continuously for some architectures,
3932 and make them available as substitutes. These are the default source of
3933 substitutes; which can be overridden by passing the
3934 @option{--substitute-urls} option either to @command{guix-daemon}
3935 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3936 or to client tools such as @command{guix package}
3937 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3940 Substitute URLs can be either HTTP or HTTPS.
3941 HTTPS is recommended because communications are encrypted; conversely,
3942 using HTTP makes all communications visible to an eavesdropper, who
3943 could use the information gathered to determine, for instance, whether
3944 your system has unpatched security vulnerabilities.
3946 Substitutes from the official build farms are enabled by default when
3947 using Guix System (@pxref{GNU Distribution}). However,
3948 they are disabled by default when using Guix on a foreign distribution,
3949 unless you have explicitly enabled them via one of the recommended
3950 installation steps (@pxref{Installation}). The following paragraphs
3951 describe how to enable or disable substitutes for the official build
3952 farm; the same procedure can also be used to enable substitutes for any
3953 other substitute server.
3955 @node Substitute Server Authorization
3956 @subsection Substitute Server Authorization
3959 @cindex substitutes, authorization thereof
3960 @cindex access control list (ACL), for substitutes
3961 @cindex ACL (access control list), for substitutes
3962 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER-1}}, @code{@value{SUBSTITUTE-SERVER-2}} or a mirror, you
3963 must add the relevant public key to the access control list (ACL) of archive
3964 imports, using the @command{guix archive} command (@pxref{Invoking guix
3965 archive}). Doing so implies that you trust the substitute server to not
3966 be compromised and to serve genuine substitutes.
3969 If you are using Guix System, you can skip this section: Guix System
3970 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER-1}} and
3971 @code{@value{SUBSTITUTE-SERVER-2}} by default.
3974 The public keys for each of the project maintained substitute servers
3975 are installed along with Guix, in @code{@var{prefix}/share/guix/}, where
3976 @var{prefix} is the installation prefix of Guix. If you installed Guix
3977 from source, make sure you checked the GPG signature of
3978 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3979 Then, you can run something like this:
3982 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
3983 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
3986 Once this is in place, the output of a command like @code{guix build}
3987 should change from something like:
3990 $ guix build emacs --dry-run
3991 The following derivations would be built:
3992 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3993 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3994 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3995 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
4003 $ guix build emacs --dry-run
4004 112.3 MB would be downloaded:
4005 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
4006 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
4007 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
4008 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
4013 The text changed from ``The following derivations would be built'' to
4014 ``112.3 MB would be downloaded''. This indicates that substitutes from
4015 the configured substitute servers are usable and will be downloaded,
4016 when possible, for future builds.
4018 @cindex substitutes, how to disable
4019 The substitute mechanism can be disabled globally by running
4020 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
4021 guix-daemon}). It can also be disabled temporarily by passing the
4022 @option{--no-substitutes} option to @command{guix package},
4023 @command{guix build}, and other command-line tools.
4025 @node Getting Substitutes from Other Servers
4026 @subsection Getting Substitutes from Other Servers
4028 @cindex substitute servers, adding more
4029 Guix can look up and fetch substitutes from several servers. This is
4030 useful when you are using packages from additional channels for which
4031 the official server does not have substitutes but another server
4032 provides them. Another situation where this is useful is when you would
4033 prefer to download from your organization's substitute server, resorting
4034 to the official server only as a fallback or dismissing it altogether.
4036 You can give Guix a list of substitute server URLs and it will check
4037 them in the specified order. You also need to explicitly authorize the
4038 public keys of substitute servers to instruct Guix to accept the
4039 substitutes they sign.
4041 On Guix System, this is achieved by modifying the configuration of the
4042 @code{guix} service. Since the @code{guix} service is part of the
4043 default lists of services, @code{%base-services} and
4044 @code{%desktop-services}, you can use @code{modify-services} to change
4045 its configuration and add the URLs and substitute keys that you want
4046 (@pxref{Service Reference, @code{modify-services}}).
4048 As an example, suppose you want to fetch substitutes from
4049 @code{guix.example.org} and to authorize the signing key of that server,
4050 in addition to the default @code{@value{SUBSTITUTE-SERVER-1}} and
4051 @code{@value{SUBSTITUTE-SERVER-2}}. The resulting operating system
4052 configuration will look something like:
4058 ;; Assume we're starting from '%desktop-services'. Replace it
4059 ;; with the list of services you're actually using.
4060 (modify-services %desktop-services
4061 (guix-service-type config =>
4065 (append (list "https://guix.example.org")
4066 %default-substitute-urls))
4068 (append (list (local-file "./key.pub"))
4069 %default-authorized-guix-keys)))))))
4072 This assumes that the file @file{key.pub} contains the signing key of
4073 @code{guix.example.org}. With this change in place in your operating
4074 system configuration file (say @file{/etc/config.scm}), you can
4075 reconfigure and restart the @code{guix-daemon} service or reboot so the
4076 changes take effect:
4079 $ sudo guix system reconfigure /etc/config.scm
4080 $ sudo herd restart guix-daemon
4083 If you're running Guix on a ``foreign distro'', you would instead take
4084 the following steps to get substitutes from additional servers:
4088 Edit the service configuration file for @code{guix-daemon}; when using
4089 systemd, this is normally
4090 @file{/etc/systemd/system/guix-daemon.service}. Add the
4091 @option{--substitute-urls} option on the @command{guix-daemon} command
4092 line and list the URLs of interest (@pxref{daemon-substitute-urls,
4093 @code{guix-daemon --substitute-urls}}):
4096 @dots{} --substitute-urls='https://guix.example.org @value{SUBSTITUTE-URLS}'
4100 Restart the daemon. For systemd, it goes like this:
4103 systemctl daemon-reload
4104 systemctl restart guix-daemon.service
4108 Authorize the key of the new server (@pxref{Invoking guix archive}):
4111 guix archive --authorize < key.pub
4114 Again this assumes @file{key.pub} contains the public key that
4115 @code{guix.example.org} uses to sign substitutes.
4118 Now you're all set! Substitutes will be preferably taken from
4119 @code{https://guix.example.org}, using
4120 @code{@value{SUBSTITUTE-SERVER-1}} then
4121 @code{@value{SUBSTITUTE-SERVER-2}} as fallback options. Of course you
4122 can list as many substitute servers as you like, with the caveat that
4123 substitute lookup can be slowed down if too many servers need to be
4126 Note that there are also situations where one may want to add the URL of
4127 a substitute server @emph{without} authorizing its key.
4128 @xref{Substitute Authentication}, to understand this fine point.
4130 @node Substitute Authentication
4131 @subsection Substitute Authentication
4133 @cindex digital signatures
4134 Guix detects and raises an error when attempting to use a substitute
4135 that has been tampered with. Likewise, it ignores substitutes that are
4136 not signed, or that are not signed by one of the keys listed in the ACL.
4138 There is one exception though: if an unauthorized server provides
4139 substitutes that are @emph{bit-for-bit identical} to those provided by
4140 an authorized server, then the unauthorized server becomes eligible for
4141 downloads. For example, assume we have chosen two substitute servers
4145 --substitute-urls="https://a.example.org https://b.example.org"
4149 @cindex reproducible builds
4150 If the ACL contains only the key for @samp{b.example.org}, and if
4151 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
4152 then Guix will download substitutes from @samp{a.example.org} because it
4153 comes first in the list and can be considered a mirror of
4154 @samp{b.example.org}. In practice, independent build machines usually
4155 produce the same binaries, thanks to bit-reproducible builds (see
4158 When using HTTPS, the server's X.509 certificate is @emph{not} validated
4159 (in other words, the server is not authenticated), contrary to what
4160 HTTPS clients such as Web browsers usually do. This is because Guix
4161 authenticates substitute information itself, as explained above, which
4162 is what we care about (whereas X.509 certificates are about
4163 authenticating bindings between domain names and public keys).
4165 @node Proxy Settings
4166 @subsection Proxy Settings
4170 Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
4171 @env{https_proxy} environment variables can be set in the environment of
4172 @command{guix-daemon} and are honored for downloads of substitutes.
4173 Note that the value of those environment variables in the environment
4174 where @command{guix build}, @command{guix package}, and other client
4175 commands are run has @emph{absolutely no effect}.
4177 @node Substitution Failure
4178 @subsection Substitution Failure
4180 Even when a substitute for a derivation is available, sometimes the
4181 substitution attempt will fail. This can happen for a variety of
4182 reasons: the substitute server might be offline, the substitute may
4183 recently have been deleted, the connection might have been interrupted,
4186 When substitutes are enabled and a substitute for a derivation is
4187 available, but the substitution attempt fails, Guix will attempt to
4188 build the derivation locally depending on whether or not
4189 @option{--fallback} was given (@pxref{fallback-option,, common build
4190 option @option{--fallback}}). Specifically, if @option{--fallback} was
4191 omitted, then no local build will be performed, and the derivation is
4192 considered to have failed. However, if @option{--fallback} was given,
4193 then Guix will attempt to build the derivation locally, and the success
4194 or failure of the derivation depends on the success or failure of the
4195 local build. Note that when substitutes are disabled or no substitute
4196 is available for the derivation in question, a local build will
4197 @emph{always} be performed, regardless of whether or not
4198 @option{--fallback} was given.
4200 To get an idea of how many substitutes are available right now, you can
4201 try running the @command{guix weather} command (@pxref{Invoking guix
4202 weather}). This command provides statistics on the substitutes provided
4205 @node On Trusting Binaries
4206 @subsection On Trusting Binaries
4208 @cindex trust, of pre-built binaries
4209 Today, each individual's control over their own computing is at the
4210 mercy of institutions, corporations, and groups with enough power and
4211 determination to subvert the computing infrastructure and exploit its
4212 weaknesses. While using substitutes can be convenient, we encourage
4213 users to also build on their own, or even run their own build farm, such
4214 that the project run substitute servers are less of an interesting
4215 target. One way to help is by publishing the software you build using
4216 @command{guix publish} so that others have one more choice of server to
4217 download substitutes from (@pxref{Invoking guix publish}).
4219 Guix has the foundations to maximize build reproducibility
4220 (@pxref{Features}). In most cases, independent builds of a given
4221 package or derivation should yield bit-identical results. Thus, through
4222 a diverse set of independent package builds, we can strengthen the
4223 integrity of our systems. The @command{guix challenge} command aims to
4224 help users assess substitute servers, and to assist developers in
4225 finding out about non-deterministic package builds (@pxref{Invoking guix
4226 challenge}). Similarly, the @option{--check} option of @command{guix
4227 build} allows users to check whether previously-installed substitutes
4228 are genuine by rebuilding them locally (@pxref{build-check,
4229 @command{guix build --check}}).
4231 In the future, we want Guix to have support to publish and retrieve
4232 binaries to/from other users, in a peer-to-peer fashion. If you would
4233 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
4235 @node Packages with Multiple Outputs
4236 @section Packages with Multiple Outputs
4238 @cindex multiple-output packages
4239 @cindex package outputs
4242 Often, packages defined in Guix have a single @dfn{output}---i.e., the
4243 source package leads to exactly one directory in the store. When running
4244 @command{guix install glibc}, one installs the default output of the
4245 GNU libc package; the default output is called @code{out}, but its name
4246 can be omitted as shown in this command. In this particular case, the
4247 default output of @code{glibc} contains all the C header files, shared
4248 libraries, static libraries, Info documentation, and other supporting
4251 Sometimes it is more appropriate to separate the various types of files
4252 produced from a single source package into separate outputs. For
4253 instance, the GLib C library (used by GTK+ and related packages)
4254 installs more than 20 MiB of reference documentation as HTML pages.
4255 To save space for users who do not need it, the documentation goes to a
4256 separate output, called @code{doc}. To install the main GLib output,
4257 which contains everything but the documentation, one would run:
4263 @cindex documentation
4264 The command to install its documentation is:
4267 guix install glib:doc
4270 Some packages install programs with different ``dependency footprints''.
4271 For instance, the WordNet package installs both command-line tools and
4272 graphical user interfaces (GUIs). The former depend solely on the C
4273 library, whereas the latter depend on Tcl/Tk and the underlying X
4274 libraries. In this case, we leave the command-line tools in the default
4275 output, whereas the GUIs are in a separate output. This allows users
4276 who do not need the GUIs to save space. The @command{guix size} command
4277 can help find out about such situations (@pxref{Invoking guix size}).
4278 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
4280 There are several such multiple-output packages in the GNU distribution.
4281 Other conventional output names include @code{lib} for libraries and
4282 possibly header files, @code{bin} for stand-alone programs, and
4283 @code{debug} for debugging information (@pxref{Installing Debugging
4284 Files}). The outputs of a packages are listed in the third column of
4285 the output of @command{guix package --list-available} (@pxref{Invoking
4289 @node Invoking guix gc
4290 @section Invoking @command{guix gc}
4292 @cindex garbage collector
4294 Packages that are installed, but not used, may be @dfn{garbage-collected}.
4295 The @command{guix gc} command allows users to explicitly run the garbage
4296 collector to reclaim space from the @file{/gnu/store} directory. It is
4297 the @emph{only} way to remove files from @file{/gnu/store}---removing
4298 files or directories manually may break it beyond repair!
4301 @cindex garbage collector roots
4302 The garbage collector has a set of known @dfn{roots}: any file under
4303 @file{/gnu/store} reachable from a root is considered @dfn{live} and
4304 cannot be deleted; any other file is considered @dfn{dead} and may be
4305 deleted. The set of garbage collector roots (``GC roots'' for short)
4306 includes default user profiles; by default, the symlinks under
4307 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
4308 added with @command{guix build --root}, for example (@pxref{Invoking
4309 guix build}). The @command{guix gc --list-roots} command lists them.
4311 Prior to running @code{guix gc --collect-garbage} to make space, it is
4312 often useful to remove old generations from user profiles; that way, old
4313 package builds referenced by those generations can be reclaimed. This
4314 is achieved by running @code{guix package --delete-generations}
4315 (@pxref{Invoking guix package}).
4317 Our recommendation is to run a garbage collection periodically, or when
4318 you are short on disk space. For instance, to guarantee that at least
4319 5@tie{}GB are available on your disk, simply run:
4325 It is perfectly safe to run as a non-interactive periodic job
4326 (@pxref{Scheduled Job Execution}, for how to set up such a job).
4327 Running @command{guix gc} with no arguments will collect as
4328 much garbage as it can, but that is often inconvenient: you may find
4329 yourself having to rebuild or re-download software that is ``dead'' from
4330 the GC viewpoint but that is necessary to build other pieces of
4331 software---e.g., the compiler tool chain.
4333 The @command{guix gc} command has three modes of operation: it can be
4334 used to garbage-collect any dead files (the default), to delete specific
4335 files (the @option{--delete} option), to print garbage-collector
4336 information, or for more advanced queries. The garbage collection
4337 options are as follows:
4340 @item --collect-garbage[=@var{min}]
4341 @itemx -C [@var{min}]
4342 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4343 sub-directories. This is the default operation when no option is
4346 When @var{min} is given, stop once @var{min} bytes have been collected.
4347 @var{min} may be a number of bytes, or it may include a unit as a
4348 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4349 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4351 When @var{min} is omitted, collect all the garbage.
4353 @item --free-space=@var{free}
4354 @itemx -F @var{free}
4355 Collect garbage until @var{free} space is available under
4356 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4357 as @code{500MiB}, as described above.
4359 When @var{free} or more is already available in @file{/gnu/store}, do
4360 nothing and exit immediately.
4362 @item --delete-generations[=@var{duration}]
4363 @itemx -d [@var{duration}]
4364 Before starting the garbage collection process, delete all the generations
4365 older than @var{duration}, for all the user profiles and home environment
4366 generations; when run as root, this
4367 applies to all the profiles @emph{of all the users}.
4369 For example, this command deletes all the generations of all your profiles
4370 that are older than 2 months (except generations that are current), and then
4371 proceeds to free space until at least 10 GiB are available:
4374 guix gc -d 2m -F 10G
4379 Attempt to delete all the store files and directories specified as
4380 arguments. This fails if some of the files are not in the store, or if
4381 they are still live.
4383 @item --list-failures
4384 List store items corresponding to cached build failures.
4386 This prints nothing unless the daemon was started with
4387 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4388 @option{--cache-failures}}).
4391 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4395 List store items in use by currently running processes. These store
4396 items are effectively considered GC roots: they cannot be deleted.
4398 @item --clear-failures
4399 Remove the specified store items from the failed-build cache.
4401 Again, this option only makes sense when the daemon is started with
4402 @option{--cache-failures}. Otherwise, it does nothing.
4405 Show the list of dead files and directories still present in the
4406 store---i.e., files and directories no longer reachable from any root.
4409 Show the list of live store files and directories.
4413 In addition, the references among existing store files can be queried:
4419 @cindex package dependencies
4420 List the references (respectively, the referrers) of store files given
4426 List the requisites of the store files passed as arguments. Requisites
4427 include the store files themselves, their references, and the references
4428 of these, recursively. In other words, the returned list is the
4429 @dfn{transitive closure} of the store files.
4431 @xref{Invoking guix size}, for a tool to profile the size of the closure
4432 of an element. @xref{Invoking guix graph}, for a tool to visualize
4433 the graph of references.
4437 Return the derivation(s) leading to the given store items
4438 (@pxref{Derivations}).
4440 For example, this command:
4443 guix gc --derivers $(guix package -I ^emacs$ | cut -f4)
4447 returns the @file{.drv} file(s) leading to the @code{emacs} package
4448 installed in your profile.
4450 Note that there may be zero matching @file{.drv} files, for instance
4451 because these files have been garbage-collected. There can also be more
4452 than one matching @file{.drv} due to fixed-output derivations.
4455 Lastly, the following options allow you to check the integrity of the
4456 store and to control disk usage.
4460 @item --verify[=@var{options}]
4461 @cindex integrity, of the store
4462 @cindex integrity checking
4463 Verify the integrity of the store.
4465 By default, make sure that all the store items marked as valid in the
4466 database of the daemon actually exist in @file{/gnu/store}.
4468 When provided, @var{options} must be a comma-separated list containing one
4469 or more of @code{contents} and @code{repair}.
4471 When passing @option{--verify=contents}, the daemon computes the
4472 content hash of each store item and compares it against its hash in the
4473 database. Hash mismatches are reported as data corruptions. Because it
4474 traverses @emph{all the files in the store}, this command can take a
4475 long time, especially on systems with a slow disk drive.
4477 @cindex repairing the store
4478 @cindex corruption, recovering from
4479 Using @option{--verify=repair} or @option{--verify=contents,repair}
4480 causes the daemon to try to repair corrupt store items by fetching
4481 substitutes for them (@pxref{Substitutes}). Because repairing is not
4482 atomic, and thus potentially dangerous, it is available only to the
4483 system administrator. A lightweight alternative, when you know exactly
4484 which items in the store are corrupt, is @command{guix build --repair}
4485 (@pxref{Invoking guix build}).
4488 @cindex deduplication
4489 Optimize the store by hard-linking identical files---this is
4490 @dfn{deduplication}.
4492 The daemon performs deduplication after each successful build or archive
4493 import, unless it was started with @option{--disable-deduplication}
4494 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4495 this option is primarily useful when the daemon was running with
4496 @option{--disable-deduplication}.
4500 @node Invoking guix pull
4501 @section Invoking @command{guix pull}
4503 @cindex upgrading Guix
4504 @cindex updating Guix
4505 @cindex @command{guix pull}
4507 @cindex security, @command{guix pull}
4508 @cindex authenticity, of code obtained with @command{guix pull}
4509 Packages are installed or upgraded to the latest version available in
4510 the distribution currently available on your local machine. To update
4511 that distribution, along with the Guix tools, you must run @command{guix
4512 pull}: the command downloads the latest Guix source code and package
4513 descriptions, and deploys it. Source code is downloaded from a
4514 @uref{https://git-scm.com, Git} repository, by default the official
4515 GNU@tie{}Guix repository, though this can be customized. @command{guix
4516 pull} ensures that the code it downloads is @emph{authentic} by
4517 verifying that commits are signed by Guix developers.
4519 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4520 (@pxref{Channels}) specified by one of the followings, in this order:
4524 the @option{--channels} option;
4526 the user's @file{~/.config/guix/channels.scm} file;
4528 the system-wide @file{/etc/guix/channels.scm} file;
4530 the built-in default channels specified in the @code{%default-channels}
4534 On completion, @command{guix package} will use packages and package
4535 versions from this just-retrieved copy of Guix. Not only that, but all
4536 the Guix commands and Scheme modules will also be taken from that latest
4537 version. New @command{guix} sub-commands added by the update also
4540 Any user can update their Guix copy using @command{guix pull}, and the
4541 effect is limited to the user who ran @command{guix pull}. For
4542 instance, when user @code{root} runs @command{guix pull}, this has no
4543 effect on the version of Guix that user @code{alice} sees, and vice
4546 The result of running @command{guix pull} is a @dfn{profile} available
4547 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4548 make sure to add it to the beginning of your search path so that you use
4549 the latest version, and similarly for the Info manual
4550 (@pxref{Documentation}):
4553 export PATH="$HOME/.config/guix/current/bin:$PATH"
4554 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4557 The @option{--list-generations} or @option{-l} option lists past generations
4558 produced by @command{guix pull}, along with details about their provenance:
4562 Generation 1 Jun 10 2018 00:18:18
4564 repository URL: https://git.savannah.gnu.org/git/guix.git
4565 branch: origin/master
4566 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4568 Generation 2 Jun 11 2018 11:02:49
4570 repository URL: https://git.savannah.gnu.org/git/guix.git
4571 branch: origin/master
4572 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4574 Generation 3 Jun 13 2018 23:31:07 (current)
4576 repository URL: https://git.savannah.gnu.org/git/guix.git
4577 branch: origin/master
4578 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4581 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4582 describe the current status of Guix.
4584 This @code{~/.config/guix/current} profile works exactly like the profiles
4585 created by @command{guix package} (@pxref{Invoking guix package}). That
4586 is, you can list generations, roll back to the previous
4587 generation---i.e., the previous Guix---and so on:
4590 $ guix pull --roll-back
4591 switched from generation 3 to 2
4592 $ guix pull --delete-generations=1
4593 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4596 You can also use @command{guix package} (@pxref{Invoking guix package})
4597 to manage the profile by naming it explicitly:
4599 $ guix package -p ~/.config/guix/current --roll-back
4600 switched from generation 3 to 2
4601 $ guix package -p ~/.config/guix/current --delete-generations=1
4602 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4605 The @command{guix pull} command is usually invoked with no arguments,
4606 but it supports the following options:
4609 @item --url=@var{url}
4610 @itemx --commit=@var{commit}
4611 @itemx --branch=@var{branch}
4612 Download code for the @code{guix} channel from the specified @var{url}, at the
4613 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4614 string), or @var{branch}.
4616 @cindex @file{channels.scm}, configuration file
4617 @cindex configuration file for channels
4618 These options are provided for convenience, but you can also specify your
4619 configuration in the @file{~/.config/guix/channels.scm} file or using the
4620 @option{--channels} option (see below).
4622 @item --channels=@var{file}
4623 @itemx -C @var{file}
4624 Read the list of channels from @var{file} instead of
4625 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4626 @var{file} must contain Scheme code that
4627 evaluates to a list of channel objects. @xref{Channels}, for more
4630 @cindex channel news
4633 Display news written by channel authors for their users for changes made
4634 since the previous generation (@pxref{Channels, Writing Channel News}).
4635 When @option{--details} is passed, additionally display new and upgraded
4638 You can view that information for previous generations with
4639 @command{guix pull -l}.
4641 @item --list-generations[=@var{pattern}]
4642 @itemx -l [@var{pattern}]
4643 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4644 is provided, the subset of generations that match @var{pattern}.
4645 The syntax of @var{pattern} is the same as with @code{guix package
4646 --list-generations} (@pxref{Invoking guix package}).
4648 By default, this prints information about the channels used in each
4649 revision as well as the corresponding news entries. If you pass
4650 @option{--details}, it will also print the list of packages added and
4651 upgraded in each generation compared to the previous one.
4654 Instruct @option{--list-generations} or @option{--news} to display more
4655 information about the differences between subsequent generations---see
4659 @cindex rolling back
4660 @cindex undoing transactions
4661 @cindex transactions, undoing
4662 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4663 undo the last transaction.
4665 @item --switch-generation=@var{pattern}
4666 @itemx -S @var{pattern}
4668 Switch to a particular generation defined by @var{pattern}.
4670 @var{pattern} may be either a generation number or a number prefixed
4671 with ``+'' or ``-''. The latter means: move forward/backward by a
4672 specified number of generations. For example, if you want to return to
4673 the latest generation after @option{--roll-back}, use
4674 @option{--switch-generation=+1}.
4676 @item --delete-generations[=@var{pattern}]
4677 @itemx -d [@var{pattern}]
4678 When @var{pattern} is omitted, delete all generations except the current
4681 This command accepts the same patterns as @option{--list-generations}.
4682 When @var{pattern} is specified, delete the matching generations. When
4683 @var{pattern} specifies a duration, generations @emph{older} than the
4684 specified duration match. For instance, @option{--delete-generations=1m}
4685 deletes generations that are more than one month old.
4687 If the current generation matches, it is @emph{not} deleted.
4689 Note that deleting generations prevents rolling back to them.
4690 Consequently, this command must be used with care.
4692 @xref{Invoking guix describe}, for a way to display information about the
4693 current generation only.
4695 @item --profile=@var{profile}
4696 @itemx -p @var{profile}
4697 Use @var{profile} instead of @file{~/.config/guix/current}.
4701 Show which channel commit(s) would be used and what would be built or
4702 substituted but do not actually do it.
4704 @item --allow-downgrades
4705 Allow pulling older or unrelated revisions of channels than those
4708 @cindex downgrade attacks, protection against
4709 By default, @command{guix pull} protects against so-called ``downgrade
4710 attacks'' whereby the Git repository of a channel would be reset to an
4711 earlier or unrelated revision of itself, potentially leading you to
4712 install older, known-vulnerable versions of software packages.
4715 Make sure you understand its security implications before using
4716 @option{--allow-downgrades}.
4719 @item --disable-authentication
4720 Allow pulling channel code without authenticating it.
4722 @cindex authentication, of channel code
4723 By default, @command{guix pull} authenticates code downloaded from
4724 channels by verifying that its commits are signed by authorized
4725 developers, and raises an error if this is not the case. This option
4726 instructs it to not perform any such verification.
4729 Make sure you understand its security implications before using
4730 @option{--disable-authentication}.
4733 @item --system=@var{system}
4734 @itemx -s @var{system}
4735 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4736 the system type of the build host.
4739 Use the bootstrap Guile to build the latest Guix. This option is only
4740 useful to Guix developers.
4743 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4744 repository and branch to pull from, as well as @emph{additional} repositories
4745 containing package modules that should be deployed. @xref{Channels}, for more
4748 In addition, @command{guix pull} supports all the common build options
4749 (@pxref{Common Build Options}).
4751 @node Invoking guix time-machine
4752 @section Invoking @command{guix time-machine}
4754 @cindex @command{guix time-machine}
4755 @cindex pinning, channels
4756 @cindex replicating Guix
4757 @cindex reproducibility, of Guix
4759 The @command{guix time-machine} command provides access to other
4760 revisions of Guix, for example to install older versions of packages,
4761 or to reproduce a computation in an identical environment. The revision
4762 of Guix to be used is defined by a commit or by a channel
4763 description file created by @command{guix describe}
4764 (@pxref{Invoking guix describe}).
4766 The general syntax is:
4769 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4772 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4773 @command{guix} command of the specified revision. The @var{options} that define
4774 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4777 @item --url=@var{url}
4778 @itemx --commit=@var{commit}
4779 @itemx --branch=@var{branch}
4780 Use the @code{guix} channel from the specified @var{url}, at the
4781 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4782 string), or @var{branch}.
4784 @item --channels=@var{file}
4785 @itemx -C @var{file}
4786 Read the list of channels from @var{file}. @var{file} must contain
4787 Scheme code that evaluates to a list of channel objects.
4788 @xref{Channels} for more information.
4791 As for @command{guix pull}, the absence of any options means that the
4792 latest commit on the master branch will be used. The command
4795 guix time-machine -- build hello
4798 will thus build the package @code{hello} as defined in the master branch,
4799 which is in general a newer revision of Guix than you have installed.
4800 Time travel works in both directions!
4802 Note that @command{guix time-machine} can trigger builds of channels and
4803 their dependencies, and these are controlled by the standard build
4804 options (@pxref{Common Build Options}).
4809 @c TODO: Remove this once we're more confident about API stability.
4811 The functionality described here is a ``technology preview'' as of version
4812 @value{VERSION}. As such, the interface is subject to change.
4816 @cindex composition of Guix revisions
4817 Sometimes you might need to mix packages from the revision of Guix you're
4818 currently running with packages available in a different revision of Guix.
4819 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4820 revisions in arbitrary ways.
4822 @cindex inferior packages
4823 Technically, an ``inferior'' is essentially a separate Guix process connected
4824 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4825 @code{(guix inferior)} module allows you to create inferiors and to
4826 communicate with them. It also provides a high-level interface to browse and
4827 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4829 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4830 to interact with a separate revision of Guix. For example, let's assume you
4831 want to install in your profile the current @code{guile} package, along with
4832 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4833 because the newer @code{guile-json} has an incompatible API and you want to
4834 run your code against the old API@. To do that, you could write a manifest for
4835 use by @code{guix package --manifest} (@pxref{Writing Manifests}); in that
4836 manifest, you would create an inferior for that old Guix revision you care
4837 about, and you would look up the @code{guile-json} package in the inferior:
4840 (use-modules (guix inferior) (guix channels)
4841 (srfi srfi-1)) ;for 'first'
4844 ;; This is the old revision from which we want to
4845 ;; extract guile-json.
4848 (url "https://git.savannah.gnu.org/git/guix.git")
4850 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4853 ;; An inferior representing the above revision.
4854 (inferior-for-channels channels))
4856 ;; Now create a manifest with the current "guile" package
4857 ;; and the old "guile-json" package.
4859 (list (first (lookup-inferior-packages inferior "guile-json"))
4860 (specification->package "guile")))
4863 On its first run, @command{guix package --manifest} might have to build the
4864 channel you specified before it can create the inferior; subsequent runs will
4865 be much faster because the Guix revision will be cached.
4867 The @code{(guix inferior)} module provides the following procedures to open an
4870 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4871 [#:cache-directory] [#:ttl]
4872 Return an inferior for @var{channels}, a list of channels. Use the cache at
4873 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4874 This procedure opens a new connection to the build daemon.
4876 As a side effect, this procedure may build or substitute binaries for
4877 @var{channels}, which can take time.
4880 @deffn {Scheme Procedure} open-inferior @var{directory} @
4881 [#:command "bin/guix"]
4882 Open the inferior Guix in @var{directory}, running
4883 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4884 the inferior could not be launched.
4887 @cindex inferior packages
4888 The procedures listed below allow you to obtain and manipulate inferior
4891 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4892 Return the list of packages known to @var{inferior}.
4895 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4897 Return the sorted list of inferior packages matching @var{name} in
4898 @var{inferior}, with highest version numbers first. If @var{version} is true,
4899 return only packages with a version number prefixed by @var{version}.
4902 @deffn {Scheme Procedure} inferior-package? @var{obj}
4903 Return true if @var{obj} is an inferior package.
4906 @deffn {Scheme Procedure} inferior-package-name @var{package}
4907 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4908 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4909 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4910 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4911 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4912 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4913 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4914 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4915 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4916 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4917 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4918 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4919 These procedures are the counterpart of package record accessors
4920 (@pxref{package Reference}). Most of them work by querying the inferior
4921 @var{package} comes from, so the inferior must still be live when you call
4925 Inferior packages can be used transparently like any other package or
4926 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4927 transparently handled by the @code{packages->manifest} procedure, which is
4928 commonly used in manifests (@pxref{Invoking guix package, the
4929 @option{--manifest} option of @command{guix package}}). Thus you can insert
4930 an inferior package pretty much anywhere you would insert a regular package:
4931 in manifests, in the @code{packages} field of your @code{operating-system}
4932 declaration, and so on.
4934 @node Invoking guix describe
4935 @section Invoking @command{guix describe}
4937 @cindex reproducibility
4938 @cindex replicating Guix
4939 Often you may want to answer questions like: ``Which revision of Guix am I
4940 using?'' or ``Which channels am I using?'' This is useful information in many
4941 situations: if you want to @emph{replicate} an environment on a different
4942 machine or user account, if you want to report a bug or to determine what
4943 change in the channels you are using caused it, or if you want to record your
4944 system state for reproducibility purposes. The @command{guix describe}
4945 command answers these questions.
4947 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4948 displays the channel(s) that it was built from, including their repository URL
4949 and commit IDs (@pxref{Channels}):
4953 Generation 10 Sep 03 2018 17:32:44 (current)
4955 repository URL: https://git.savannah.gnu.org/git/guix.git
4957 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4960 If you're familiar with the Git version control system, this is similar in
4961 spirit to @command{git describe}; the output is also similar to that of
4962 @command{guix pull --list-generations}, but limited to the current generation
4963 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4964 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4965 information is all it takes to describe the revision of Guix you're using, and
4966 also to replicate it.
4968 To make it easier to replicate Guix, @command{guix describe} can also be asked
4969 to return a list of channels instead of the human-readable description above:
4972 $ guix describe -f channels
4975 (url "https://git.savannah.gnu.org/git/guix.git")
4977 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4979 (make-channel-introduction
4980 "9edb3f66fd807b096b48283debdcddccfea34bad"
4981 (openpgp-fingerprint
4982 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4986 You can save this to a file and feed it to @command{guix pull -C} on some
4987 other machine or at a later point in time, which will instantiate @emph{this
4988 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4989 From there on, since you're able to deploy the same revision of Guix, you can
4990 just as well @emph{replicate a complete software environment}. We humbly
4991 think that this is @emph{awesome}, and we hope you'll like it too!
4993 The details of the options supported by @command{guix describe} are as
4997 @item --format=@var{format}
4998 @itemx -f @var{format}
4999 Produce output in the specified @var{format}, one of:
5003 produce human-readable output;
5005 produce a list of channel specifications that can be passed to @command{guix
5006 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
5008 @item channels-sans-intro
5009 like @code{channels}, but omit the @code{introduction} field; use it to
5010 produce a channel specification suitable for Guix version 1.1.0 or
5011 earlier---the @code{introduction} field has to do with channel
5012 authentication (@pxref{Channels, Channel Authentication}) and is not
5013 supported by these older versions;
5016 produce a list of channel specifications in JSON format;
5018 produce a list of channel specifications in Recutils format.
5021 @item --list-formats
5022 Display available formats for @option{--format} option.
5024 @item --profile=@var{profile}
5025 @itemx -p @var{profile}
5026 Display information about @var{profile}.
5029 @node Invoking guix archive
5030 @section Invoking @command{guix archive}
5032 @cindex @command{guix archive}
5034 The @command{guix archive} command allows users to @dfn{export} files
5035 from the store into a single archive, and to later @dfn{import} them on
5036 a machine that runs Guix.
5037 In particular, it allows store files to be transferred from one machine
5038 to the store on another machine.
5041 If you're looking for a way to produce archives in a format suitable for
5042 tools other than Guix, @pxref{Invoking guix pack}.
5045 @cindex exporting store items
5046 To export store files as an archive to standard output, run:
5049 guix archive --export @var{options} @var{specifications}...
5052 @var{specifications} may be either store file names or package
5053 specifications, as for @command{guix package} (@pxref{Invoking guix
5054 package}). For instance, the following command creates an archive
5055 containing the @code{gui} output of the @code{git} package and the main
5056 output of @code{emacs}:
5059 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
5062 If the specified packages are not built yet, @command{guix archive}
5063 automatically builds them. The build process may be controlled with the
5064 common build options (@pxref{Common Build Options}).
5066 To transfer the @code{emacs} package to a machine connected over SSH,
5070 guix archive --export -r emacs | ssh the-machine guix archive --import
5074 Similarly, a complete user profile may be transferred from one machine
5075 to another like this:
5078 guix archive --export -r $(readlink -f ~/.guix-profile) | \
5079 ssh the-machine guix archive --import
5083 However, note that, in both examples, all of @code{emacs} and the
5084 profile as well as all of their dependencies are transferred (due to
5085 @option{-r}), regardless of what is already available in the store on
5086 the target machine. The @option{--missing} option can help figure out
5087 which items are missing from the target store. The @command{guix copy}
5088 command simplifies and optimizes this whole process, so this is probably
5089 what you should use in this case (@pxref{Invoking guix copy}).
5091 @cindex nar, archive format
5092 @cindex normalized archive (nar)
5093 @cindex nar bundle, archive format
5094 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
5095 format (described below), and the output of @command{guix archive
5096 --export} (and input of @command{guix archive --import}) is a @dfn{nar
5100 comparable in spirit to `tar', but with differences
5101 that make it more appropriate for our purposes. First, rather than
5102 recording all Unix metadata for each file, the nar format only mentions
5103 the file type (regular, directory, or symbolic link); Unix permissions
5104 and owner/group are dismissed. Second, the order in which directory
5105 entries are stored always follows the order of file names according to
5106 the C locale collation order. This makes archive production fully
5109 That nar bundle format is essentially the concatenation of zero or more
5110 nars along with metadata for each store item it contains: its file name,
5111 references, corresponding derivation, and a digital signature.
5113 When exporting, the daemon digitally signs the contents of the archive,
5114 and that digital signature is appended. When importing, the daemon
5115 verifies the signature and rejects the import in case of an invalid
5116 signature or if the signing key is not authorized.
5117 @c FIXME: Add xref to daemon doc about signatures.
5119 The main options are:
5123 Export the specified store files or packages (see below). Write the
5124 resulting archive to the standard output.
5126 Dependencies are @emph{not} included in the output, unless
5127 @option{--recursive} is passed.
5131 When combined with @option{--export}, this instructs @command{guix archive}
5132 to include dependencies of the given items in the archive. Thus, the
5133 resulting archive is self-contained: it contains the closure of the
5134 exported store items.
5137 Read an archive from the standard input, and import the files listed
5138 therein into the store. Abort if the archive has an invalid digital
5139 signature, or if it is signed by a public key not among the authorized
5140 keys (see @option{--authorize} below).
5143 Read a list of store file names from the standard input, one per line,
5144 and write on the standard output the subset of these files missing from
5147 @item --generate-key[=@var{parameters}]
5148 @cindex signing, archives
5149 Generate a new key pair for the daemon. This is a prerequisite before
5150 archives can be exported with @option{--export}. This
5151 operation is usually instantaneous but it can take time if the system's
5152 entropy pool needs to be refilled. On Guix System,
5153 @code{guix-service-type} takes care of generating this key pair the
5156 The generated key pair is typically stored under @file{/etc/guix}, in
5157 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
5158 key, which must be kept secret). When @var{parameters} is omitted,
5159 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
5160 versions before 1.6.0, it is a 4096-bit RSA key.
5161 Alternatively, @var{parameters} can specify
5162 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
5163 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
5164 Libgcrypt Reference Manual}).
5167 @cindex authorizing, archives
5168 Authorize imports signed by the public key passed on standard input.
5169 The public key must be in ``s-expression advanced format''---i.e., the
5170 same format as the @file{signing-key.pub} file.
5172 The list of authorized keys is kept in the human-editable file
5173 @file{/etc/guix/acl}. The file contains
5174 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
5175 s-expressions''} and is structured as an access-control list in the
5176 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
5179 @item --extract=@var{directory}
5180 @itemx -x @var{directory}
5181 Read a single-item archive as served by substitute servers
5182 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
5183 low-level operation needed in only very narrow use cases; see below.
5185 For example, the following command extracts the substitute for Emacs
5186 served by @code{@value{SUBSTITUTE-SERVER-1}} to @file{/tmp/emacs}:
5190 https://@value{SUBSTITUTE-SERVER-1}/nar/gzip/@dots{}-emacs-24.5 \
5191 | gunzip | guix archive -x /tmp/emacs
5194 Single-item archives are different from multiple-item archives produced
5195 by @command{guix archive --export}; they contain a single store item,
5196 and they do @emph{not} embed a signature. Thus this operation does
5197 @emph{no} signature verification and its output should be considered
5200 The primary purpose of this operation is to facilitate inspection of
5201 archive contents coming from possibly untrusted substitute servers
5202 (@pxref{Invoking guix challenge}).
5206 Read a single-item archive as served by substitute servers
5207 (@pxref{Substitutes}) and print the list of files it contains, as in
5212 https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-emacs-26.3 \
5213 | lzip -d | guix archive -t
5218 @c *********************************************************************
5223 @cindex @file{channels.scm}, configuration file
5224 @cindex configuration file for channels
5225 @cindex @command{guix pull}, configuration file
5226 @cindex configuration of @command{guix pull}
5227 Guix and its package collection are updated by running @command{guix pull}
5228 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
5229 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
5230 customized by defining @dfn{channels} in the
5231 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
5232 of a Git repository to be deployed, and @command{guix pull} can be instructed
5233 to pull from one or more channels. In other words, channels can be used
5234 to @emph{customize} and to @emph{extend} Guix, as we will see below.
5235 Guix is able to take into account security concerns and deal with authenticated
5239 * Specifying Additional Channels:: Extending the package collection.
5240 * Using a Custom Guix Channel:: Using a customized Guix.
5241 * Replicating Guix:: Running the @emph{exact same} Guix.
5242 * Channel Authentication:: How Guix verifies what it fetches.
5243 * Channels with Substitutes:: Using channels with available substitutes.
5244 * Creating a Channel:: How to write your custom channel.
5245 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
5246 * Declaring Channel Dependencies:: How to depend on other channels.
5247 * Specifying Channel Authorizations:: Defining channel authors authorizations.
5248 * Primary URL:: Distinguishing mirror to original.
5249 * Writing Channel News:: Communicating information to channel's users.
5252 @node Specifying Additional Channels
5253 @section Specifying Additional Channels
5255 @cindex extending the package collection (channels)
5256 @cindex variant packages (channels)
5257 You can specify @emph{additional channels} to pull from. To use a channel, write
5258 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
5259 @emph{in addition} to the default Guix channel(s):
5261 @vindex %default-channels
5263 ;; Add variant packages to those Guix provides.
5265 (name 'variant-packages)
5266 (url "https://example.org/variant-packages.git"))
5271 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
5272 add a channel the list of channels that the variable @code{%default-channels}
5273 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
5274 Manual}). With this file in place, @command{guix pull} builds not only Guix
5275 but also the package modules from your own repository. The result in
5276 @file{~/.config/guix/current} is the union of Guix with your own package
5281 Generation 19 Aug 27 2018 16:20:48
5283 repository URL: https://git.savannah.gnu.org/git/guix.git
5285 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
5286 variant-packages dd3df5e
5287 repository URL: https://example.org/variant-packages.git
5289 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
5293 The output of @command{guix describe} above shows that we're now running
5294 Generation@tie{}19 and that it includes
5295 both Guix and packages from the @code{variant-personal-packages} channel
5296 (@pxref{Invoking guix describe}).
5298 @node Using a Custom Guix Channel
5299 @section Using a Custom Guix Channel
5301 The channel called @code{guix} specifies where Guix itself---its command-line
5302 tools as well as its package collection---should be downloaded. For instance,
5303 suppose you want to update from another copy of the Guix repository at
5304 @code{example.org}, and specifically the @code{super-hacks} branch, you can
5305 write in @code{~/.config/guix/channels.scm} this specification:
5308 ;; Tell 'guix pull' to use another repo.
5311 (url "https://example.org/another-guix.git")
5312 (branch "super-hacks")))
5316 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
5317 branch of the repository at @code{example.org}. The authentication concern is
5318 addressed below (@pxref{Channel Authentication}).
5320 @node Replicating Guix
5321 @section Replicating Guix
5323 @cindex pinning, channels
5324 @cindex replicating Guix
5325 @cindex reproducibility, of Guix
5326 The @command{guix describe} command shows precisely which commits were
5327 used to build the instance of Guix we're using (@pxref{Invoking guix
5328 describe}). We can replicate this instance on another machine or at a
5329 different point in time by providing a channel specification ``pinned''
5330 to these commits that looks like this:
5333 ;; Deploy specific commits of my channels of interest.
5336 (url "https://git.savannah.gnu.org/git/guix.git")
5337 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5339 (name 'variant-packages)
5340 (url "https://example.org/variant-packages.git")
5341 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5344 To obtain this pinned channel specification, the easiest way is to run
5345 @command{guix describe} and to save its output in the @code{channels}
5346 format in a file, like so:
5349 guix describe -f channels > channels.scm
5352 The resulting @file{channels.scm} file can be passed to the @option{-C}
5353 option of @command{guix pull} (@pxref{Invoking guix pull}) or
5354 @command{guix time-machine} (@pxref{Invoking guix time-machine}), as in
5358 guix time-machine -C channels.scm -- shell python -- python3
5361 Given the @file{channels.scm} file, the command above will always fetch
5362 the @emph{exact same Guix instance}, then use that instance to run the
5363 exact same Python (@pxref{Invoking guix shell}). On any machine, at any
5364 time, it ends up running the exact same binaries, bit for bit.
5367 Pinned channels address a problem similar to ``lock files'' as
5368 implemented by some deployment tools---they let you pin and reproduce a
5369 set of packages. In the case of Guix though, you are effectively
5370 pinning the entire package set as defined at the given channel commits;
5371 in fact, you are pinning all of Guix, including its core modules and
5372 command-line tools. You're also getting strong guarantees that you are,
5373 indeed, obtaining the exact same software.
5375 This gives you super powers, allowing you to track the provenance of binary
5376 artifacts with very fine grain, and to reproduce software environments at
5377 will---some sort of ``meta reproducibility'' capabilities, if you will.
5378 @xref{Inferiors}, for another way to take advantage of these super powers.
5380 @node Channel Authentication
5381 @section Channel Authentication
5383 @anchor{channel-authentication}
5384 @cindex authentication, of channel code
5385 The @command{guix pull} and @command{guix time-machine} commands
5386 @dfn{authenticate} the code retrieved from channels: they make sure each
5387 commit that is fetched is signed by an authorized developer. The goal
5388 is to protect from unauthorized modifications to the channel that would
5389 lead users to run malicious code.
5391 As a user, you must provide a @dfn{channel introduction} in your
5392 channels file so that Guix knows how to authenticate its first commit.
5393 A channel specification, including its introduction, looks something
5398 (name 'some-channel)
5399 (url "https://example.org/some-channel.git")
5401 (make-channel-introduction
5402 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5403 (openpgp-fingerprint
5404 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5407 The specification above shows the name and URL of the channel. The call
5408 to @code{make-channel-introduction} above specifies that authentication
5409 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5410 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5412 For the main channel, called @code{guix}, you automatically get that
5413 information from your Guix installation. For other channels, include
5414 the channel introduction provided by the channel authors in your
5415 @file{channels.scm} file. Make sure you retrieve the channel
5416 introduction from a trusted source since that is the root of your trust.
5418 If you're curious about the authentication mechanics, read on!
5420 @node Channels with Substitutes
5421 @section Channels with Substitutes
5423 When running @command{guix pull}, Guix will first compile the
5424 definitions of every available package. This is an expensive operation
5425 for which substitutes (@pxref{Substitutes}) may be available. The
5426 following snippet in @file{channels.scm} will ensure that @command{guix
5427 pull} uses the latest commit with available substitutes for the package
5428 definitions: this is done by querying the continuous integration
5429 server at @url{https://ci.guix.gnu.org}.
5432 (use-modules (guix ci))
5434 (list (channel-with-substitutes-available
5435 %default-guix-channel
5436 "https://ci.guix.gnu.org"))
5439 Note that this does not mean that all the packages that you will
5440 install after running @command{guix pull} will have available
5441 substitutes. It only ensures that @command{guix pull} will not try to
5442 compile package definitions. This is particularly useful when using
5443 machines with limited resources.
5445 @node Creating a Channel
5446 @section Creating a Channel
5448 @cindex personal packages (channels)
5449 @cindex channels, for personal packages
5450 Let's say you have a bunch of custom package variants or personal packages
5451 that you think would make little sense to contribute to the Guix project, but
5452 would like to have these packages transparently available to you at the
5453 command line. You would first write modules containing those package
5454 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5455 then you and anyone else can use it as an additional channel to get packages
5458 @c What follows stems from discussions at
5459 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5460 @c earlier discussions on guix-devel@gnu.org.
5462 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5463 publish your personal channel to the world, we would like to share a few words
5468 Before publishing a channel, please consider contributing your package
5469 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5470 to free software of all sorts, and packages in Guix proper are readily
5471 available to all Guix users and benefit from the project's quality assurance
5475 When you maintain package definitions outside Guix, we, Guix developers,
5476 consider that @emph{the compatibility burden is on you}. Remember that
5477 package modules and package definitions are just Scheme code that uses various
5478 programming interfaces (APIs). We want to remain free to change these APIs to
5479 keep improving Guix, possibly in ways that break your channel. We never
5480 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5484 Corollary: if you're using an external channel and that channel breaks, please
5485 @emph{report the issue to the channel authors}, not to the Guix project.
5488 You've been warned! Having said this, we believe external channels are a
5489 practical way to exert your freedom to augment Guix' package collection and to
5490 share your improvements, which are basic tenets of
5491 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5492 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5495 To create a channel, create a Git repository containing your own package
5496 modules and make it available. The repository can contain anything, but a
5497 useful channel will contain Guile modules that export packages. Once you
5498 start using a channel, Guix will behave as if the root directory of that
5499 channel's Git repository has been added to the Guile load path (@pxref{Load
5500 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5501 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5502 module, then the module will be available under the name @code{(my-packages
5503 my-tools)}, and you will be able to use it like any other module
5504 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5506 As a channel author, consider bundling authentication material with your
5507 channel so that users can authenticate it. @xref{Channel
5508 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5512 @node Package Modules in a Sub-directory
5513 @section Package Modules in a Sub-directory
5515 @cindex subdirectory, channels
5516 As a channel author, you may want to keep your channel modules in a
5517 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5518 add a meta-data file @file{.guix-channel} that contains:
5526 @node Declaring Channel Dependencies
5527 @section Declaring Channel Dependencies
5529 @cindex dependencies, channels
5530 @cindex meta-data, channels
5531 Channel authors may decide to augment a package collection provided by other
5532 channels. They can declare their channel to be dependent on other channels in
5533 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5534 the channel repository.
5536 The meta-data file should contain a simple S-expression like this:
5543 (name some-collection)
5544 (url "https://example.org/first-collection.git")
5546 ;; The 'introduction' bit below is optional: you would
5547 ;; provide it for dependencies that can be authenticated.
5549 (channel-introduction
5551 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5552 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5554 (name some-other-collection)
5555 (url "https://example.org/second-collection.git")
5556 (branch "testing"))))
5559 In the above example this channel is declared to depend on two other channels,
5560 which will both be fetched automatically. The modules provided by the channel
5561 will be compiled in an environment where the modules of all these declared
5562 channels are available.
5564 For the sake of reliability and maintainability, you should avoid dependencies
5565 on channels that you don't control, and you should aim to keep the number of
5566 dependencies to a minimum.
5568 @node Specifying Channel Authorizations
5569 @section Specifying Channel Authorizations
5571 @cindex channel authorizations
5572 @anchor{channel-authorizations}
5573 As we saw above, Guix ensures the source code it pulls from channels
5574 comes from authorized developers. As a channel author, you need to
5575 specify the list of authorized developers in the
5576 @file{.guix-authorizations} file in the channel's Git repository. The
5577 authentication rule is simple: each commit must be signed by a key
5578 listed in the @file{.guix-authorizations} file of its parent
5579 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5580 (DAG). Each commit can have zero or more parents; ``regular'' commits
5581 have one parent and merge commits have two parent commits. Read
5582 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5583 for Computer Scientists}} for a great overview.} The
5584 @file{.guix-authorizations} file looks like this:
5587 ;; Example '.guix-authorizations' file.
5590 (version 0) ;current file format version
5592 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5594 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5596 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5600 Each fingerprint is followed by optional key/value pairs, as in the
5601 example above. Currently these key/value pairs are ignored.
5603 This authentication rule creates a chicken-and-egg issue: how do we
5604 authenticate the first commit? Related to that: how do we deal with
5605 channels whose repository history contains unsigned commits and lack
5606 @file{.guix-authorizations}? And how do we fork existing channels?
5608 @cindex channel introduction
5609 Channel introductions answer these questions by describing the first
5610 commit of a channel that should be authenticated. The first time a
5611 channel is fetched with @command{guix pull} or @command{guix
5612 time-machine}, the command looks up the introductory commit and verifies
5613 that it is signed by the specified OpenPGP key. From then on, it
5614 authenticates commits according to the rule above. Authentication fails
5615 if the target commit is neither a descendant nor an ancestor of the
5616 introductory commit.
5618 Additionally, your channel must provide all the OpenPGP keys that were
5619 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5620 files, which can be either binary or ``ASCII-armored''. By default,
5621 those @file{.key} files are searched for in the branch named
5622 @code{keyring} but you can specify a different branch name in
5623 @code{.guix-channel} like so:
5628 (keyring-reference "my-keyring-branch"))
5631 To summarize, as the author of a channel, there are three things you have
5632 to do to allow users to authenticate your code:
5636 Export the OpenPGP keys of past and present committers with @command{gpg
5637 --export} and store them in @file{.key} files, by default in a branch
5638 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5641 Introduce an initial @file{.guix-authorizations} in the channel's
5642 repository. Do that in a signed commit (@pxref{Commit Access}, for
5643 information on how to sign Git commits.)
5646 Advertise the channel introduction, for instance on your channel's web
5647 page. The channel introduction, as we saw above, is the commit/key
5648 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5649 the fingerprint of the OpenPGP used to sign it.
5652 Before pushing to your public Git repository, you can run @command{guix
5653 git-authenticate} to verify that you did sign all the commits you are
5654 about to push with an authorized key:
5657 guix git authenticate @var{commit} @var{signer}
5661 where @var{commit} and @var{signer} are your channel introduction.
5662 @xref{Invoking guix git authenticate}, for details.
5664 Publishing a signed channel requires discipline: any mistake, such as an
5665 unsigned commit or a commit signed by an unauthorized key, will prevent
5666 users from pulling from your channel---well, that's the whole point of
5667 authentication! Pay attention to merges in particular: merge commits
5668 are considered authentic if and only if they are signed by a key present
5669 in the @file{.guix-authorizations} file of @emph{both} branches.
5672 @section Primary URL
5674 @cindex primary URL, channels
5675 Channel authors can indicate the primary URL of their channel's Git
5676 repository in the @file{.guix-channel} file, like so:
5681 (url "https://example.org/guix.git"))
5684 This allows @command{guix pull} to determine whether it is pulling code
5685 from a mirror of the channel; when that is the case, it warns the user
5686 that the mirror might be stale and displays the primary URL@. That way,
5687 users cannot be tricked into fetching code from a stale mirror that does
5688 not receive security updates.
5690 This feature only makes sense for authenticated repositories, such as
5691 the official @code{guix} channel, for which @command{guix pull} ensures
5692 the code it fetches is authentic.
5694 @node Writing Channel News
5695 @section Writing Channel News
5697 @cindex news, for channels
5698 Channel authors may occasionally want to communicate to their users
5699 information about important changes in the channel. You'd send them all
5700 an email, but that's not convenient.
5702 Instead, channels can provide a @dfn{news file}; when the channel users
5703 run @command{guix pull}, that news file is automatically read and
5704 @command{guix pull --news} can display the announcements that correspond
5705 to the new commits that have been pulled, if any.
5707 To do that, channel authors must first declare the name of the news file
5708 in their @file{.guix-channel} file:
5713 (news-file "etc/news.txt"))
5716 The news file itself, @file{etc/news.txt} in this example, must look
5717 something like this:
5722 (entry (tag "the-bug-fix")
5723 (title (en "Fixed terrible bug")
5725 (body (en "@@emph@{Good news@}! It's fixed!")
5726 (eo "Certe ĝi pli bone funkcias nun!")))
5727 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5728 (title (en "Added a great package")
5729 (ca "Què vol dir guix?"))
5730 (body (en "Don't miss the @@code@{hello@} package!"))))
5733 While the news file is using the Scheme syntax, avoid naming it with a
5734 @file{.scm} extension or else it will get picked up when building the
5735 channel and yield an error since it is not a valid module.
5736 Alternatively, you can move the channel module to a subdirectory and
5737 store the news file in another directory.
5739 The file consists of a list of @dfn{news entries}. Each entry is
5740 associated with a commit or tag: it describes changes made in this
5741 commit, possibly in preceding commits as well. Users see entries only
5742 the first time they obtain the commit the entry refers to.
5744 The @code{title} field should be a one-line summary while @code{body}
5745 can be arbitrarily long, and both can contain Texinfo markup
5746 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5747 a list of language tag/message tuples, which allows @command{guix pull}
5748 to display news in the language that corresponds to the user's locale.
5750 If you want to translate news using a gettext-based workflow, you can
5751 extract translatable strings with @command{xgettext} (@pxref{xgettext
5752 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5753 you write news entries in English first, the command below creates a PO
5754 file containing the strings to translate:
5757 xgettext -o news.po -l scheme -ken etc/news.txt
5760 To sum up, yes, you could use your channel as a blog. But beware, this
5761 is @emph{not quite} what your users might expect.
5763 @c *********************************************************************
5765 @chapter Development
5767 @cindex software development
5768 If you are a software developer, Guix provides tools that you should find
5769 helpful---independently of the language you're developing in. This is what
5770 this chapter is about.
5772 The @command{guix shell} command provides a convenient way to set up
5773 one-off software environments, be it for development purposes or to run
5774 a command without installing it in your profile. The @command{guix
5775 pack} command allows you to create @dfn{application bundles} that can be
5776 easily distributed to users who do not run Guix.
5779 * Invoking guix shell:: Spawning one-off software environments.
5780 * Invoking guix environment:: Setting up development environments.
5781 * Invoking guix pack:: Creating software bundles.
5782 * The GCC toolchain:: Working with languages supported by GCC.
5783 * Invoking guix git authenticate:: Authenticating Git repositories.
5786 @node Invoking guix shell
5787 @section Invoking @command{guix shell}
5789 @cindex reproducible build environments
5790 @cindex development environments
5791 @cindex @command{guix environment}
5792 @cindex environment, package build environment
5793 The purpose of @command{guix shell} is to make it easy to create one-off
5794 software environments, without changing one's profile. It is typically
5795 used to create development environments; it is also a convenient way to
5796 run applications without ``polluting'' your profile.
5799 The @command{guix shell} command was recently introduced to supersede
5800 @command{guix environment} (@pxref{Invoking guix environment}). If you
5801 are familiar with @command{guix environment}, you will notice that it is
5802 similar but also---we hope!---more convenient.
5805 The general syntax is:
5808 guix shell [@var{options}] [@var{package}@dots{}]
5811 The following example creates an environment containing Python and NumPy,
5812 building or downloading any missing package, and runs the
5813 @command{python3} command in that environment:
5816 guix shell python python-numpy -- python3
5819 Development environments can be created as in the example below, which
5820 spawns an interactive shell containing all the dependencies and
5821 environment variables needed to work on Inkscape:
5824 guix shell --development inkscape
5827 Exiting the shell places the user back in the original environment
5828 before @command{guix shell} was invoked. The next garbage collection
5829 (@pxref{Invoking guix gc}) may clean up packages that were installed in
5830 the environment and that are no longer used outside of it.
5832 As an added convenience, @command{guix shell} will try to do what you
5833 mean when it is invoked interactively without any other arguments
5840 If it finds a @file{manifest.scm} in the current working directory or
5841 any of its parents, it uses this manifest as though it was given via @code{--manifest}.
5842 Likewise, if it finds a @file{guix.scm} in the same directories, it uses
5843 it to build a development profile as though both @code{--development}
5844 and @code{--file} were present.
5845 In either case, the file will only be loaded if the directory it
5846 resides in is listed in
5847 @file{~/.config/guix/shell-authorized-directories}.
5848 This provides an easy way to define, share, and enter development
5851 By default, the shell session or command runs in an @emph{augmented}
5852 environment, where the new packages are added to search path environment
5853 variables such as @code{PATH}. You can, instead, choose to create an
5854 @emph{isolated} environment containing nothing but the packages you
5855 asked for. Passing the @option{--pure} option clears environment
5856 variable definitions found in the parent environment@footnote{Be sure to
5857 use the @option{--check} option the first time you use @command{guix
5858 shell} interactively to make sure the shell does not undo the effect of
5859 @option{--pure}.}; passing @option{--container} goes one step further by
5860 spawning a @dfn{container} isolated from the rest of the system:
5863 guix shell --container emacs gcc-toolchain
5866 The command above spawns an interactive shell in a container where
5867 nothing but @code{emacs}, @code{gcc-toolchain}, and their dependencies
5868 is available. The container lacks network access and shares no files
5869 other than the current working directory with the surrounding
5870 environment. This is useful to prevent access to system-wide resources
5871 such as @file{/usr/bin} on foreign distros.
5873 This @option{--container} option can also prove useful if you wish to
5874 run a security-sensitive application, such as a web browser, in an
5875 isolated environment. For example, the command below launches
5876 Ungoogled-Chromium in an isolated environment, this time sharing network
5877 access with the host and preserving its @code{DISPLAY} environment
5878 variable, but without even sharing the current directory:
5881 guix shell --container --network --no-cwd ungoogled-chromium \
5882 --preserve='^DISPLAY$' -- chromium
5885 @vindex GUIX_ENVIRONMENT
5886 @command{guix shell} defines the @env{GUIX_ENVIRONMENT}
5887 variable in the shell it spawns; its value is the file name of the
5888 profile of this environment. This allows users to, say, define a
5889 specific prompt for development environments in their @file{.bashrc}
5890 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5893 if [ -n "$GUIX_ENVIRONMENT" ]
5895 export PS1="\u@@\h \w [dev]\$ "
5900 ...@: or to browse the profile:
5903 $ ls "$GUIX_ENVIRONMENT/bin"
5906 The available options are summarized below.
5910 Set up the environment and check whether the shell would clobber
5911 environment variables. It's a good idea to use this option the first
5912 time you run @command{guix shell} for an interactive session to make
5913 sure your setup is correct.
5915 For example, if the shell modifies the @env{PATH} environment variable,
5916 report it since you would get a different environment than what you
5919 Such problems usually indicate that the shell startup files are
5920 unexpectedly modifying those environment variables. For example, if you
5921 are using Bash, make sure that environment variables are set or modified
5922 in @file{~/.bash_profile} and @emph{not} in @file{~/.bashrc}---the
5923 former is sourced only by log-in shells. @xref{Bash Startup Files,,,
5924 bash, The GNU Bash Reference Manual}, for details on Bash start-up
5927 @anchor{shell-development-option}
5930 Cause @command{guix shell} to include in the environment the
5931 dependencies of the following package rather than the package itself.
5932 This can be combined with other packages. For instance, the command
5933 below starts an interactive shell containing the build-time dependencies
5934 of GNU@tie{}Guile, plus Autoconf, Automake, and Libtool:
5937 guix shell -D guile autoconf automake libtool
5940 @item --expression=@var{expr}
5941 @itemx -e @var{expr}
5942 Create an environment for the package or list of packages that
5943 @var{expr} evaluates to.
5945 For example, running:
5948 guix shell -D -e '(@@ (gnu packages maths) petsc-openmpi)'
5951 starts a shell with the environment for this specific variant of the
5957 guix shell -e '(@@ (gnu) %base-packages)'
5960 starts a shell with all the base system packages available.
5962 The above commands only use the default output of the given packages.
5963 To select other outputs, two element tuples can be specified:
5966 guix shell -e '(list (@@ (gnu packages bash) bash) "include")'
5969 @xref{package-development-manifest,
5970 @code{package->development-manifest}}, for information on how to write a
5971 manifest for the development environment of a package.
5973 @item --file=@var{file}
5974 @itemx -f @var{file}
5975 Create an environment containing the package or list of packages that
5976 the code within @var{file} evaluates to.
5978 As an example, @var{file} might contain a definition like this
5979 (@pxref{Defining Packages}):
5982 @verbatiminclude environment-gdb.scm
5985 With the file above, you can enter a development environment for GDB by
5989 guix shell -D -f gdb-devel.scm
5992 @anchor{shell-manifest}
5993 @item --manifest=@var{file}
5994 @itemx -m @var{file}
5995 Create an environment for the packages contained in the manifest object
5996 returned by the Scheme code in @var{file}. This option can be repeated
5997 several times, in which case the manifests are concatenated.
5999 This is similar to the same-named option in @command{guix package}
6000 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
6003 @xref{Writing Manifests}, for information on how to write a manifest.
6004 See @option{--export-manifest} below on how to obtain a first manifest.
6006 @cindex manifest, exporting
6007 @anchor{shell-export-manifest}
6008 @item --export-manifest
6009 Write to standard output a manifest suitable for @option{--manifest}
6010 corresponding to given command-line options.
6012 This is a way to ``convert'' command-line arguments into a manifest.
6013 For example, imagine you are tired of typing long lines and would like
6014 to get a manifest equivalent to this command line:
6017 guix shell -D guile git emacs emacs-geiser emacs-geiser-guile
6020 Just add @option{--export-manifest} to the command line above:
6023 guix shell --export-manifest \
6024 -D guile git emacs emacs-geiser emacs-geiser-guile
6028 ... and you get a manifest along these lines:
6031 (concatenate-manifests
6032 (list (specifications->manifest
6036 "emacs-geiser-guile"))
6037 (package->development-manifest
6038 (specification->package "guile"))))
6041 You can store it into a file, say @file{manifest.scm}, and from there
6042 pass it to @command{guix shell} or indeed pretty much any @command{guix}
6046 guix shell -m manifest.scm
6049 Voilà, you've converted a long command line into a manifest! That
6050 conversion process honors package transformation options (@pxref{Package
6051 Transformation Options}) so it should be lossless.
6053 @item --profile=@var{profile}
6054 @itemx -p @var{profile}
6055 Create an environment containing the packages installed in @var{profile}.
6056 Use @command{guix package} (@pxref{Invoking guix package}) to create
6057 and manage profiles.
6060 Unset existing environment variables when building the new environment, except
6061 those specified with @option{--preserve} (see below). This has the effect of
6062 creating an environment in which search paths only contain package inputs.
6064 @item --preserve=@var{regexp}
6065 @itemx -E @var{regexp}
6066 When used alongside @option{--pure}, preserve the environment variables
6067 matching @var{regexp}---in other words, put them on a ``white list'' of
6068 environment variables that must be preserved. This option can be repeated
6072 guix shell --pure --preserve=^SLURM openmpi @dots{} \
6076 This example runs @command{mpirun} in a context where the only environment
6077 variables defined are @env{PATH}, environment variables whose name starts
6078 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
6081 @item --search-paths
6082 Display the environment variable definitions that make up the
6085 @item --system=@var{system}
6086 @itemx -s @var{system}
6087 Attempt to build for @var{system}---e.g., @code{i686-linux}.
6092 Run @var{command} within an isolated container. The current working
6093 directory outside the container is mapped inside the container.
6094 Additionally, unless overridden with @option{--user}, a dummy home
6095 directory is created that matches the current user's home directory, and
6096 @file{/etc/passwd} is configured accordingly.
6098 The spawned process runs as the current user outside the container. Inside
6099 the container, it has the same UID and GID as the current user, unless
6100 @option{--user} is passed (see below).
6104 For containers, share the network namespace with the host system.
6105 Containers created without this flag only have access to the loopback
6108 @item --link-profile
6110 For containers, link the environment profile to @file{~/.guix-profile}
6111 within the container and set @code{GUIX_ENVIRONMENT} to that.
6112 This is equivalent to making @file{~/.guix-profile} a symlink to the
6113 actual profile within the container.
6114 Linking will fail and abort the environment if the directory already
6115 exists, which will certainly be the case if @command{guix shell}
6116 was invoked in the user's home directory.
6118 Certain packages are configured to look in @file{~/.guix-profile} for
6119 configuration files and data;@footnote{For example, the
6120 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
6121 for additional fonts.} @option{--link-profile} allows these programs to
6122 behave as expected within the environment.
6124 @item --user=@var{user}
6125 @itemx -u @var{user}
6126 For containers, use the username @var{user} in place of the current
6127 user. The generated @file{/etc/passwd} entry within the container will
6128 contain the name @var{user}, the home directory will be
6129 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
6130 the UID and GID inside the container are 1000. @var{user}
6131 need not exist on the system.
6133 Additionally, any shared or exposed path (see @option{--share} and
6134 @option{--expose} respectively) whose target is within the current user's
6135 home directory will be remapped relative to @file{/home/USER}; this
6136 includes the automatic mapping of the current working directory.
6139 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
6141 guix shell --container --user=foo \
6142 --expose=$HOME/test \
6143 --expose=/tmp/target=$HOME/target
6146 While this will limit the leaking of user identity through home paths
6147 and each of the user fields, this is only one useful component of a
6148 broader privacy/anonymity solution---not one in and of itself.
6151 For containers, the default behavior is to share the current working
6152 directory with the isolated container and immediately change to that
6153 directory within the container. If this is undesirable,
6154 @option{--no-cwd} will cause the current working directory to @emph{not}
6155 be automatically shared and will change to the user's home directory
6156 within the container instead. See also @option{--user}.
6158 @item --expose=@var{source}[=@var{target}]
6159 @itemx --share=@var{source}[=@var{target}]
6160 For containers, @option{--expose} (resp. @option{--share}) exposes the
6161 file system @var{source} from the host system as the read-only
6162 (resp. writable) file system @var{target} within the container. If
6163 @var{target} is not specified, @var{source} is used as the target mount
6164 point in the container.
6166 The example below spawns a Guile REPL in a container in which the user's
6167 home directory is accessible read-only via the @file{/exchange}
6171 guix shell --container --expose=$HOME=/exchange guile -- guile
6174 @item --rebuild-cache
6175 @cindex caching, of profiles
6176 @cindex caching, in @command{guix shell}
6177 In most cases, @command{guix shell} caches the environment so that
6178 subsequent uses are instantaneous. Least-recently used cache entries
6179 are periodically removed. The cache is also invalidated, when using
6180 @option{--file} or @option{--manifest}, anytime the corresponding file
6183 The @option{--rebuild-cache} forces the cached environment to be
6184 refreshed. This is useful when using @option{--file} or
6185 @option{--manifest} and the @command{guix.scm} or @command{manifest.scm}
6186 file has external dependencies, or if its behavior depends, say, on
6187 environment variables.
6189 @item --root=@var{file}
6190 @itemx -r @var{file}
6191 @cindex persistent environment
6192 @cindex garbage collector root, for environments
6193 Make @var{file} a symlink to the profile for this environment, and
6194 register it as a garbage collector root.
6196 This is useful if you want to protect your environment from garbage
6197 collection, to make it ``persistent''.
6199 When this option is omitted, @command{guix shell} caches profiles so
6200 that subsequent uses of the same environment are instantaneous---this is
6201 comparable to using @option{--root} except that @command{guix shell}
6202 takes care of periodically removing the least-recently used garbage
6205 In some cases, @command{guix shell} does not cache profiles---e.g., if
6206 transformation options such as @option{--with-latest} are used. In
6207 those cases, the environment is protected from garbage collection only
6208 for the duration of the @command{guix shell} session. This means that
6209 next time you recreate the same environment, you could have to rebuild
6210 or re-download packages.
6212 @xref{Invoking guix gc}, for more on GC roots.
6215 @command{guix shell} also supports all of the common build options that
6216 @command{guix build} supports (@pxref{Common Build Options}) as well as
6217 package transformation options (@pxref{Package Transformation Options}).
6219 @node Invoking guix environment
6220 @section Invoking @command{guix environment}
6222 The purpose of @command{guix environment} is to assist in creating
6223 development environments.
6225 @quotation Deprecation warning
6226 The @command{guix environment} command is deprecated in favor of
6227 @command{guix shell}, which performs similar functions but is more
6228 convenient to use. @xref{Invoking guix shell}.
6230 Being deprecated, @command{guix environment} is slated for eventual
6231 removal, but the Guix project is committed to keeping it until May 1st,
6232 2023. Please get in touch with us at @email{guix-devel@@gnu.org} if you
6233 would like to discuss it.
6236 The general syntax is:
6239 guix environment @var{options} @var{package}@dots{}
6242 The following example spawns a new shell set up for the development of
6246 guix environment guile
6249 If the needed dependencies are not built yet, @command{guix environment}
6250 automatically builds them. The environment of the new shell is an
6251 augmented version of the environment that @command{guix environment} was
6252 run in. It contains the necessary search paths for building the given
6253 package added to the existing environment variables. To create
6254 a ``pure'' environment, in which the original environment variables have
6255 been unset, use the @option{--pure} option@footnote{Users sometimes
6256 wrongfully augment environment variables such as @env{PATH} in their
6257 @file{~/.bashrc} file. As a consequence, when @command{guix
6258 environment} launches it, Bash may read @file{~/.bashrc}, thereby
6259 introducing ``impurities'' in these environment variables. It is an
6260 error to define such environment variables in @file{.bashrc}; instead,
6261 they should be defined in @file{.bash_profile}, which is sourced only by
6262 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
6263 Manual}, for details on Bash start-up files.}.
6265 Exiting from a Guix environment is the same as exiting from the shell,
6266 and will place the user back in the old environment before @command{guix
6267 environment} was invoked. The next garbage collection (@pxref{Invoking
6268 guix gc}) will clean up packages that were installed from within the
6269 environment and are no longer used outside of it.
6271 @vindex GUIX_ENVIRONMENT
6272 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
6273 variable in the shell it spawns; its value is the file name of the
6274 profile of this environment. This allows users to, say, define a
6275 specific prompt for development environments in their @file{.bashrc}
6276 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
6279 if [ -n "$GUIX_ENVIRONMENT" ]
6281 export PS1="\u@@\h \w [dev]\$ "
6286 ...@: or to browse the profile:
6289 $ ls "$GUIX_ENVIRONMENT/bin"
6292 Additionally, more than one package may be specified, in which case the
6293 union of the inputs for the given packages are used. For example, the
6294 command below spawns a shell where all of the dependencies of both Guile
6295 and Emacs are available:
6298 guix environment guile emacs
6301 Sometimes an interactive shell session is not desired. An arbitrary
6302 command may be invoked by placing the @code{--} token to separate the
6303 command from the rest of the arguments:
6306 guix environment guile -- make -j4
6309 In other situations, it is more convenient to specify the list of
6310 packages needed in the environment. For example, the following command
6311 runs @command{python} from an environment containing Python@tie{}3 and
6315 guix environment --ad-hoc python-numpy python -- python3
6318 Furthermore, one might want the dependencies of a package and also some
6319 additional packages that are not build-time or runtime dependencies, but
6320 are useful when developing nonetheless. Because of this, the
6321 @option{--ad-hoc} flag is positional. Packages appearing before
6322 @option{--ad-hoc} are interpreted as packages whose dependencies will be
6323 added to the environment. Packages appearing after are interpreted as
6324 packages that will be added to the environment directly. For example,
6325 the following command creates a Guix development environment that
6326 additionally includes Git and strace:
6329 guix environment --pure guix --ad-hoc git strace
6333 Sometimes it is desirable to isolate the environment as much as
6334 possible, for maximal purity and reproducibility. In particular, when
6335 using Guix on a host distro that is not Guix System, it is desirable to
6336 prevent access to @file{/usr/bin} and other system-wide resources from
6337 the development environment. For example, the following command spawns
6338 a Guile REPL in a ``container'' where only the store and the current
6339 working directory are mounted:
6342 guix environment --ad-hoc --container guile -- guile
6346 The @option{--container} option requires Linux-libre 3.19 or newer.
6349 @cindex certificates
6350 Another typical use case for containers is to run security-sensitive
6351 applications such as a web browser. To run Eolie, we must expose and
6352 share some files and directories; we include @code{nss-certs} and expose
6353 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
6354 @env{DISPLAY} environment variable since containerized graphical
6355 applications won't display without it.
6358 guix environment --preserve='^DISPLAY$' --container --network \
6359 --expose=/etc/machine-id \
6360 --expose=/etc/ssl/certs/ \
6361 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
6362 --ad-hoc eolie nss-certs dbus -- eolie
6365 The available options are summarized below.
6369 Set up the environment and check whether the shell would clobber
6370 environment variables. @xref{Invoking guix shell, @option{--check}},
6373 @item --root=@var{file}
6374 @itemx -r @var{file}
6375 @cindex persistent environment
6376 @cindex garbage collector root, for environments
6377 Make @var{file} a symlink to the profile for this environment, and
6378 register it as a garbage collector root.
6380 This is useful if you want to protect your environment from garbage
6381 collection, to make it ``persistent''.
6383 When this option is omitted, the environment is protected from garbage
6384 collection only for the duration of the @command{guix environment}
6385 session. This means that next time you recreate the same environment,
6386 you could have to rebuild or re-download packages. @xref{Invoking guix
6387 gc}, for more on GC roots.
6389 @item --expression=@var{expr}
6390 @itemx -e @var{expr}
6391 Create an environment for the package or list of packages that
6392 @var{expr} evaluates to.
6394 For example, running:
6397 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
6400 starts a shell with the environment for this specific variant of the
6406 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
6409 starts a shell with all the base system packages available.
6411 The above commands only use the default output of the given packages.
6412 To select other outputs, two element tuples can be specified:
6415 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
6418 @item --load=@var{file}
6419 @itemx -l @var{file}
6420 Create an environment for the package or list of packages that the code
6421 within @var{file} evaluates to.
6423 As an example, @var{file} might contain a definition like this
6424 (@pxref{Defining Packages}):
6427 @verbatiminclude environment-gdb.scm
6430 @item --manifest=@var{file}
6431 @itemx -m @var{file}
6432 Create an environment for the packages contained in the manifest object
6433 returned by the Scheme code in @var{file}. This option can be repeated
6434 several times, in which case the manifests are concatenated.
6436 This is similar to the same-named option in @command{guix package}
6437 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
6440 @xref{shell-export-manifest, @command{guix shell --export-manifest}},
6441 for information on how to ``convert'' command-line options into a
6445 Include all specified packages in the resulting environment, as if an
6446 @i{ad hoc} package were defined with them as inputs. This option is
6447 useful for quickly creating an environment without having to write a
6448 package expression to contain the desired inputs.
6450 For instance, the command:
6453 guix environment --ad-hoc guile guile-sdl -- guile
6456 runs @command{guile} in an environment where Guile and Guile-SDL are
6459 Note that this example implicitly asks for the default output of
6460 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
6461 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
6462 of @code{glib} (@pxref{Packages with Multiple Outputs}).
6464 This option may be composed with the default behavior of @command{guix
6465 environment}. Packages appearing before @option{--ad-hoc} are
6466 interpreted as packages whose dependencies will be added to the
6467 environment, the default behavior. Packages appearing after are
6468 interpreted as packages that will be added to the environment directly.
6470 @item --profile=@var{profile}
6471 @itemx -p @var{profile}
6472 Create an environment containing the packages installed in @var{profile}.
6473 Use @command{guix package} (@pxref{Invoking guix package}) to create
6474 and manage profiles.
6477 Unset existing environment variables when building the new environment, except
6478 those specified with @option{--preserve} (see below). This has the effect of
6479 creating an environment in which search paths only contain package inputs.
6481 @item --preserve=@var{regexp}
6482 @itemx -E @var{regexp}
6483 When used alongside @option{--pure}, preserve the environment variables
6484 matching @var{regexp}---in other words, put them on a ``white list'' of
6485 environment variables that must be preserved. This option can be repeated
6489 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
6493 This example runs @command{mpirun} in a context where the only environment
6494 variables defined are @env{PATH}, environment variables whose name starts
6495 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
6498 @item --search-paths
6499 Display the environment variable definitions that make up the
6502 @item --system=@var{system}
6503 @itemx -s @var{system}
6504 Attempt to build for @var{system}---e.g., @code{i686-linux}.
6509 Run @var{command} within an isolated container. The current working
6510 directory outside the container is mapped inside the container.
6511 Additionally, unless overridden with @option{--user}, a dummy home
6512 directory is created that matches the current user's home directory, and
6513 @file{/etc/passwd} is configured accordingly.
6515 The spawned process runs as the current user outside the container. Inside
6516 the container, it has the same UID and GID as the current user, unless
6517 @option{--user} is passed (see below).
6521 For containers, share the network namespace with the host system.
6522 Containers created without this flag only have access to the loopback
6525 @item --link-profile
6527 For containers, link the environment profile to @file{~/.guix-profile}
6528 within the container and set @code{GUIX_ENVIRONMENT} to that.
6529 This is equivalent to making @file{~/.guix-profile} a symlink to the
6530 actual profile within the container.
6531 Linking will fail and abort the environment if the directory already
6532 exists, which will certainly be the case if @command{guix environment}
6533 was invoked in the user's home directory.
6535 Certain packages are configured to look in @file{~/.guix-profile} for
6536 configuration files and data;@footnote{For example, the
6537 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
6538 for additional fonts.} @option{--link-profile} allows these programs to
6539 behave as expected within the environment.
6541 @item --user=@var{user}
6542 @itemx -u @var{user}
6543 For containers, use the username @var{user} in place of the current
6544 user. The generated @file{/etc/passwd} entry within the container will
6545 contain the name @var{user}, the home directory will be
6546 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
6547 the UID and GID inside the container are 1000. @var{user}
6548 need not exist on the system.
6550 Additionally, any shared or exposed path (see @option{--share} and
6551 @option{--expose} respectively) whose target is within the current user's
6552 home directory will be remapped relative to @file{/home/USER}; this
6553 includes the automatic mapping of the current working directory.
6556 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
6558 guix environment --container --user=foo \
6559 --expose=$HOME/test \
6560 --expose=/tmp/target=$HOME/target
6563 While this will limit the leaking of user identity through home paths
6564 and each of the user fields, this is only one useful component of a
6565 broader privacy/anonymity solution---not one in and of itself.
6568 For containers, the default behavior is to share the current working
6569 directory with the isolated container and immediately change to that
6570 directory within the container. If this is undesirable,
6571 @option{--no-cwd} will cause the current working directory to @emph{not}
6572 be automatically shared and will change to the user's home directory
6573 within the container instead. See also @option{--user}.
6575 @item --expose=@var{source}[=@var{target}]
6576 @itemx --share=@var{source}[=@var{target}]
6577 For containers, @option{--expose} (resp. @option{--share}) exposes the
6578 file system @var{source} from the host system as the read-only
6579 (resp. writable) file system @var{target} within the container. If
6580 @var{target} is not specified, @var{source} is used as the target mount
6581 point in the container.
6583 The example below spawns a Guile REPL in a container in which the user's
6584 home directory is accessible read-only via the @file{/exchange}
6588 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
6593 @command{guix environment}
6594 also supports all of the common build options that @command{guix
6595 build} supports (@pxref{Common Build Options}) as well as package
6596 transformation options (@pxref{Package Transformation Options}).
6598 @node Invoking guix pack
6599 @section Invoking @command{guix pack}
6601 Occasionally you want to pass software to people who are not (yet!)
6602 lucky enough to be using Guix. You'd tell them to run @command{guix
6603 package -i @var{something}}, but that's not possible in this case. This
6604 is where @command{guix pack} comes in.
6607 If you are looking for ways to exchange binaries among machines that
6608 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
6609 publish}, and @ref{Invoking guix archive}.
6614 @cindex application bundle
6615 @cindex software bundle
6616 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
6617 @dfn{software bundle}: it creates a tarball or some other archive
6618 containing the binaries of the software you're interested in, and all
6619 its dependencies. The resulting archive can be used on any machine that
6620 does not have Guix, and people can run the exact same binaries as those
6621 you have with Guix. The pack itself is created in a bit-reproducible
6622 fashion, so anyone can verify that it really contains the build results
6623 that you pretend to be shipping.
6625 For example, to create a bundle containing Guile, Emacs, Geiser, and all
6626 their dependencies, you can run:
6629 $ guix pack guile emacs emacs-geiser
6631 /gnu/store/@dots{}-pack.tar.gz
6634 The result here is a tarball containing a @file{/gnu/store} directory
6635 with all the relevant packages. The resulting tarball contains a
6636 @dfn{profile} with the three packages of interest; the profile is the
6637 same as would be created by @command{guix package -i}. It is this
6638 mechanism that is used to create Guix's own standalone binary tarball
6639 (@pxref{Binary Installation}).
6641 Users of this pack would have to run
6642 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
6643 find inconvenient. To work around it, you can create, say, a
6644 @file{/opt/gnu/bin} symlink to the profile:
6647 guix pack -S /opt/gnu/bin=bin guile emacs emacs-geiser
6651 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
6653 @cindex relocatable binaries, with @command{guix pack}
6654 What if the recipient of your pack does not have root privileges on
6655 their machine, and thus cannot unpack it in the root file system? In
6656 that case, you will want to use the @option{--relocatable} option (see
6657 below). This option produces @dfn{relocatable binaries}, meaning they
6658 they can be placed anywhere in the file system hierarchy: in the example
6659 above, users can unpack your tarball in their home directory and
6660 directly run @file{./opt/gnu/bin/guile}.
6662 @cindex Docker, build an image with guix pack
6663 Alternatively, you can produce a pack in the Docker image format using
6664 the following command:
6667 guix pack -f docker -S /bin=bin guile guile-readline
6671 The result is a tarball that can be passed to the @command{docker load}
6672 command, followed by @code{docker run}:
6675 docker load < @var{file}
6676 docker run -ti guile-guile-readline /bin/guile
6680 where @var{file} is the image returned by @var{guix pack}, and
6681 @code{guile-guile-readline} is its ``image tag''. See the
6682 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
6683 documentation} for more information.
6685 @cindex Singularity, build an image with guix pack
6686 @cindex SquashFS, build an image with guix pack
6687 Yet another option is to produce a SquashFS image with the following
6691 guix pack -f squashfs bash guile emacs emacs-geiser
6695 The result is a SquashFS file system image that can either be mounted or
6696 directly be used as a file system container image with the
6697 @uref{https://www.sylabs.io/docs/, Singularity container execution
6698 environment}, using commands like @command{singularity shell} or
6699 @command{singularity exec}.
6701 Several command-line options allow you to customize your pack:
6704 @item --format=@var{format}
6705 @itemx -f @var{format}
6706 Produce a pack in the given @var{format}.
6708 The available formats are:
6712 This is the default format. It produces a tarball containing all the
6713 specified binaries and symlinks.
6716 This produces a tarball that follows the
6717 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
6718 Docker Image Specification}. The ``repository name'' as it appears in
6719 the output of the @command{docker images} command is computed from
6720 package names passed on the command line or in the manifest file.
6723 This produces a SquashFS image containing all the specified binaries and
6724 symlinks, as well as empty mount points for virtual file systems like
6728 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
6729 For that reason, @command{guix pack -f squashfs} always implies @code{-S
6730 /bin=bin}. Thus, your @command{guix pack} invocation must always start
6731 with something like:
6734 guix pack -f squashfs bash @dots{}
6737 If you forget the @code{bash} (or similar) package, @command{singularity
6738 run} and @command{singularity exec} will fail with an unhelpful ``no
6739 such file or directory'' message.
6743 This produces a Debian archive (a package with the @samp{.deb} file
6744 extension) containing all the specified binaries and symbolic links,
6745 that can be installed on top of any dpkg-based GNU(/Linux) distribution.
6746 Advanced options can be revealed via the @option{--help-deb-format}
6747 option. They allow embedding control files for more fine-grained
6748 control, such as activating specific triggers or providing a maintainer
6749 configure script to run arbitrary setup code upon installation.
6752 guix pack -f deb -C xz -S /usr/bin/hello=bin/hello hello
6756 Because archives produced with @command{guix pack} contain a collection
6757 of store items and because each @command{dpkg} package must not have
6758 conflicting files, in practice that means you likely won't be able to
6759 install more than one such archive on a given system.
6763 @command{dpkg} will assume ownership of any files contained in the pack
6764 that it does @emph{not} know about. It is unwise to install
6765 Guix-produced @samp{.deb} files on a system where @file{/gnu/store} is
6766 shared by other software, such as a Guix installation or other, non-deb
6772 @cindex relocatable binaries
6775 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
6776 anywhere in the file system hierarchy and run from there.
6778 When this option is passed once, the resulting binaries require support for
6779 @dfn{user namespaces} in the kernel Linux; when passed
6780 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
6781 PRoot support, can be thought of as the abbreviation of ``Really
6782 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
6783 other techniques if user namespaces are unavailable, and essentially
6784 work anywhere---see below for the implications.
6786 For example, if you create a pack containing Bash with:
6789 guix pack -RR -S /mybin=bin bash
6793 ...@: you can copy that pack to a machine that lacks Guix, and from your
6794 home directory as a normal user, run:
6802 In that shell, if you type @code{ls /gnu/store}, you'll notice that
6803 @file{/gnu/store} shows up and contains all the dependencies of
6804 @code{bash}, even though the machine actually lacks @file{/gnu/store}
6805 altogether! That is probably the simplest way to deploy Guix-built
6806 software on a non-Guix machine.
6809 By default, relocatable binaries rely on the @dfn{user namespace} feature of
6810 the kernel Linux, which allows unprivileged users to mount or change root.
6811 Old versions of Linux did not support it, and some GNU/Linux distributions
6814 To produce relocatable binaries that work even in the absence of user
6815 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
6816 case, binaries will try user namespace support and fall back to another
6817 @dfn{execution engine} if user namespaces are not supported. The
6818 following execution engines are supported:
6822 Try user namespaces and fall back to PRoot if user namespaces are not
6823 supported (see below).
6826 Try user namespaces and fall back to Fakechroot if user namespaces are
6827 not supported (see below).
6830 Run the program through user namespaces and abort if they are not
6834 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
6835 provides the necessary
6836 support for file system virtualization. It achieves that by using the
6837 @code{ptrace} system call on the running program. This approach has the
6838 advantage to work without requiring special kernel support, but it incurs
6839 run-time overhead every time a system call is made.
6842 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
6843 Fakechroot} virtualizes file system accesses by intercepting calls to C
6844 library functions such as @code{open}, @code{stat}, @code{exec}, and so
6845 on. Unlike PRoot, it incurs very little overhead. However, it does not
6846 always work: for example, some file system accesses made from within the
6847 C library are not intercepted, and file system accesses made @i{via}
6848 direct syscalls are not intercepted either, leading to erratic behavior.
6851 @vindex GUIX_EXECUTION_ENGINE
6852 When running a wrapped program, you can explicitly request one of the
6853 execution engines listed above by setting the
6854 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
6857 @cindex entry point, for Docker images
6858 @item --entry-point=@var{command}
6859 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
6860 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
6861 support it. @var{command} must be relative to the profile contained in the
6864 The entry point specifies the command that tools like @code{docker run} or
6865 @code{singularity run} automatically start by default. For example, you can
6869 guix pack -f docker --entry-point=bin/guile guile
6872 The resulting pack can easily be loaded and @code{docker run} with no extra
6873 arguments will spawn @code{bin/guile}:
6876 docker load -i pack.tar.gz
6877 docker run @var{image-id}
6880 @item --expression=@var{expr}
6881 @itemx -e @var{expr}
6882 Consider the package @var{expr} evaluates to.
6884 This has the same purpose as the same-named option in @command{guix
6885 build} (@pxref{Additional Build Options, @option{--expression} in
6886 @command{guix build}}).
6888 @anchor{pack-manifest}
6889 @item --manifest=@var{file}
6890 @itemx -m @var{file}
6891 Use the packages contained in the manifest object returned by the Scheme
6892 code in @var{file}. This option can be repeated several times, in which
6893 case the manifests are concatenated.
6895 This has a similar purpose as the same-named option in @command{guix
6896 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6897 same manifest files. It allows you to define a collection of packages
6898 once and use it both for creating profiles and for creating archives
6899 for use on machines that do not have Guix installed. Note that you can
6900 specify @emph{either} a manifest file @emph{or} a list of packages,
6903 @xref{Writing Manifests}, for information on how to write a manifest.
6904 @xref{shell-export-manifest, @command{guix shell --export-manifest}},
6905 for information on how to ``convert'' command-line options into a
6908 @item --system=@var{system}
6909 @itemx -s @var{system}
6910 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6911 the system type of the build host.
6913 @item --target=@var{triplet}
6914 @cindex cross-compilation
6915 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6916 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6917 configuration triplets,, autoconf, Autoconf}).
6919 @item --compression=@var{tool}
6920 @itemx -C @var{tool}
6921 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6922 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6925 @item --symlink=@var{spec}
6926 @itemx -S @var{spec}
6927 Add the symlinks specified by @var{spec} to the pack. This option can
6928 appear several times.
6930 @var{spec} has the form @code{@var{source}=@var{target}}, where
6931 @var{source} is the symlink that will be created and @var{target} is the
6934 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6935 symlink pointing to the @file{bin} sub-directory of the profile.
6937 @item --save-provenance
6938 Save provenance information for the packages passed on the command line.
6939 Provenance information includes the URL and commit of the channels in use
6942 Provenance information is saved in the
6943 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6944 usual package metadata---the name and version of each package, their
6945 propagated inputs, and so on. It is useful information to the recipient of
6946 the pack, who then knows how the pack was (supposedly) obtained.
6948 This option is not enabled by default because, like timestamps, provenance
6949 information contributes nothing to the build process. In other words, there
6950 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6951 Recording such ``silent'' metadata in the output thus potentially breaks the
6952 source-to-binary bitwise reproducibility property.
6954 @item --root=@var{file}
6955 @itemx -r @var{file}
6956 @cindex garbage collector root, for packs
6957 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6960 @item --localstatedir
6961 @itemx --profile-name=@var{name}
6962 Include the ``local state directory'', @file{/var/guix}, in the resulting
6963 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6964 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6965 @file{~root/.guix-profile}.
6967 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6968 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6969 the pack means that the store is ``complete'' and manageable by Guix;
6970 not providing it pack means that the store is ``dead'': items cannot be
6971 added to it or removed from it after extraction of the pack.
6973 One use case for this is the Guix self-contained binary tarball
6974 (@pxref{Binary Installation}).
6978 Print the name of the derivation that builds the pack.
6981 Use the bootstrap binaries to build the pack. This option is only
6982 useful to Guix developers.
6985 In addition, @command{guix pack} supports all the common build options
6986 (@pxref{Common Build Options}) and all the package transformation
6987 options (@pxref{Package Transformation Options}).
6990 @node The GCC toolchain
6991 @section The GCC toolchain
6995 @cindex linker wrapper
6996 @cindex toolchain, for C development
6997 @cindex toolchain, for Fortran development
6999 If you need a complete toolchain for compiling and linking C or C++
7000 source code, use the @code{gcc-toolchain} package. This package
7001 provides a complete GCC toolchain for C/C++ development, including GCC
7002 itself, the GNU C Library (headers and binaries, plus debugging symbols
7003 in the @code{debug} output), Binutils, and a linker wrapper.
7005 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
7006 passed to the linker, add corresponding @code{-rpath} arguments, and
7007 invoke the actual linker with this new set of arguments. You can instruct the
7008 wrapper to refuse to link against libraries not in the store by setting the
7009 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
7011 The package @code{gfortran-toolchain} provides a complete GCC toolchain
7012 for Fortran development. For other languages, please use
7013 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
7016 @node Invoking guix git authenticate
7017 @section Invoking @command{guix git authenticate}
7019 The @command{guix git authenticate} command authenticates a Git checkout
7020 following the same rule as for channels (@pxref{channel-authentication,
7021 channel authentication}). That is, starting from a given commit, it
7022 ensures that all subsequent commits are signed by an OpenPGP key whose
7023 fingerprint appears in the @file{.guix-authorizations} file of its
7026 You will find this command useful if you maintain a channel. But in
7027 fact, this authentication mechanism is useful in a broader context, so
7028 you might want to use it for Git repositories that have nothing to do
7031 The general syntax is:
7034 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
7037 By default, this command authenticates the Git checkout in the current
7038 directory; it outputs nothing and exits with exit code zero on success
7039 and non-zero on failure. @var{commit} above denotes the first commit
7040 where authentication takes place, and @var{signer} is the OpenPGP
7041 fingerprint of public key used to sign @var{commit}. Together, they
7042 form a ``channel introduction'' (@pxref{channel-authentication, channel
7043 introduction}). The options below allow you to fine-tune the process.
7046 @item --repository=@var{directory}
7047 @itemx -r @var{directory}
7048 Open the Git repository in @var{directory} instead of the current
7051 @item --keyring=@var{reference}
7052 @itemx -k @var{reference}
7053 Load OpenPGP keyring from @var{reference}, the reference of a branch
7054 such as @code{origin/keyring} or @code{my-keyring}. The branch must
7055 contain OpenPGP public keys in @file{.key} files, either in binary form
7056 or ``ASCII-armored''. By default the keyring is loaded from the branch
7057 named @code{keyring}.
7060 Display commit signing statistics upon completion.
7062 @item --cache-key=@var{key}
7063 Previously-authenticated commits are cached in a file under
7064 @file{~/.cache/guix/authentication}. This option forces the cache to be
7065 stored in file @var{key} in that directory.
7067 @item --historical-authorizations=@var{file}
7068 By default, any commit whose parent commit(s) lack the
7069 @file{.guix-authorizations} file is considered inauthentic. In
7070 contrast, this option considers the authorizations in @var{file} for any
7071 commit that lacks @file{.guix-authorizations}. The format of @var{file}
7072 is the same as that of @file{.guix-authorizations}
7073 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
7077 @c *********************************************************************
7078 @node Programming Interface
7079 @chapter Programming Interface
7081 GNU Guix provides several Scheme programming interfaces (APIs) to
7082 define, build, and query packages. The first interface allows users to
7083 write high-level package definitions. These definitions refer to
7084 familiar packaging concepts, such as the name and version of a package,
7085 its build system, and its dependencies. These definitions can then be
7086 turned into concrete build actions.
7088 Build actions are performed by the Guix daemon, on behalf of users. In a
7089 standard setup, the daemon has write access to the store---the
7090 @file{/gnu/store} directory---whereas users do not. The recommended
7091 setup also has the daemon perform builds in chroots, under specific
7092 build users, to minimize interference with the rest of the system.
7095 Lower-level APIs are available to interact with the daemon and the
7096 store. To instruct the daemon to perform a build action, users actually
7097 provide it with a @dfn{derivation}. A derivation is a low-level
7098 representation of the build actions to be taken, and the environment in
7099 which they should occur---derivations are to package definitions what
7100 assembly is to C programs. The term ``derivation'' comes from the fact
7101 that build results @emph{derive} from them.
7103 This chapter describes all these APIs in turn, starting from high-level
7104 package definitions.
7107 * Package Modules:: Packages from the programmer's viewpoint.
7108 * Defining Packages:: Defining new packages.
7109 * Defining Package Variants:: Customizing packages.
7110 * Writing Manifests:: The bill of materials of your environment.
7111 * Build Systems:: Specifying how packages are built.
7112 * Build Phases:: Phases of the build process of a package.
7113 * Build Utilities:: Helpers for your package definitions and more.
7114 * Search Paths:: Declaring search path environment variables.
7115 * The Store:: Manipulating the package store.
7116 * Derivations:: Low-level interface to package derivations.
7117 * The Store Monad:: Purely functional interface to the store.
7118 * G-Expressions:: Manipulating build expressions.
7119 * Invoking guix repl:: Programming Guix in Guile
7120 * Using Guix Interactively:: Fine-grain interaction at the REPL.
7123 @node Package Modules
7124 @section Package Modules
7126 From a programming viewpoint, the package definitions of the
7127 GNU distribution are provided by Guile modules in the @code{(gnu packages
7128 @dots{})} name space@footnote{Note that packages under the @code{(gnu
7129 packages @dots{})} module name space are not necessarily ``GNU
7130 packages''. This module naming scheme follows the usual Guile module
7131 naming convention: @code{gnu} means that these modules are distributed
7132 as part of the GNU system, and @code{packages} identifies modules that
7133 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
7134 Reference Manual}). For instance, the @code{(gnu packages emacs)}
7135 module exports a variable named @code{emacs}, which is bound to a
7136 @code{<package>} object (@pxref{Defining Packages}).
7138 The @code{(gnu packages @dots{})} module name space is
7139 automatically scanned for packages by the command-line tools. For
7140 instance, when running @code{guix install emacs}, all the @code{(gnu
7141 packages @dots{})} modules are scanned until one that exports a package
7142 object whose name is @code{emacs} is found. This package search
7143 facility is implemented in the @code{(gnu packages)} module.
7145 @cindex customization, of packages
7146 @cindex package module search path
7147 Users can store package definitions in modules with different
7148 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
7149 name and module name must match. For instance, the @code{(my-packages
7150 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
7151 relative to the load path specified with @option{--load-path} or
7152 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
7153 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
7154 these package definitions visible to the user interfaces:
7158 By adding the directory containing your package modules to the search path
7159 with the @code{-L} flag of @command{guix package} and other commands
7160 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
7161 environment variable described below.
7164 By defining a @dfn{channel} and configuring @command{guix pull} so that it
7165 pulls from it. A channel is essentially a Git repository containing package
7166 modules. @xref{Channels}, for more information on how to define and use
7170 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
7172 @defvr {Environment Variable} GUIX_PACKAGE_PATH
7173 This is a colon-separated list of directories to search for additional
7174 package modules. Directories listed in this variable take precedence
7175 over the own modules of the distribution.
7178 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
7179 each package is built based solely on other packages in the
7180 distribution. The root of this dependency graph is a small set of
7181 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
7182 bootstrap)} module. For more information on bootstrapping,
7183 @pxref{Bootstrapping}.
7185 @node Defining Packages
7186 @section Defining Packages
7188 The high-level interface to package definitions is implemented in the
7189 @code{(guix packages)} and @code{(guix build-system)} modules. As an
7190 example, the package definition, or @dfn{recipe}, for the GNU Hello
7191 package looks like this:
7194 (define-module (gnu packages hello)
7195 #:use-module (guix packages)
7196 #:use-module (guix download)
7197 #:use-module (guix build-system gnu)
7198 #:use-module (guix licenses)
7199 #:use-module (gnu packages gawk))
7201 (define-public hello
7207 (uri (string-append "mirror://gnu/hello/hello-" version
7211 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
7212 (build-system gnu-build-system)
7213 (arguments '(#:configure-flags '("--enable-silent-rules")))
7214 (inputs (list gawk))
7215 (synopsis "Hello, GNU world: An example GNU package")
7216 (description "Guess what GNU Hello prints!")
7217 (home-page "https://www.gnu.org/software/hello/")
7222 Without being a Scheme expert, the reader may have guessed the meaning
7223 of the various fields here. This expression binds the variable
7224 @code{hello} to a @code{<package>} object, which is essentially a record
7225 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
7226 This package object can be inspected using procedures found in the
7227 @code{(guix packages)} module; for instance, @code{(package-name hello)}
7228 returns---surprise!---@code{"hello"}.
7230 With luck, you may be able to import part or all of the definition of
7231 the package you are interested in from another repository, using the
7232 @code{guix import} command (@pxref{Invoking guix import}).
7234 In the example above, @code{hello} is defined in a module of its own,
7235 @code{(gnu packages hello)}. Technically, this is not strictly
7236 necessary, but it is convenient to do so: all the packages defined in
7237 modules under @code{(gnu packages @dots{})} are automatically known to
7238 the command-line tools (@pxref{Package Modules}).
7240 There are a few points worth noting in the above package definition:
7244 The @code{source} field of the package is an @code{<origin>} object
7245 (@pxref{origin Reference}, for the complete reference).
7246 Here, the @code{url-fetch} method from @code{(guix download)} is used,
7247 meaning that the source is a file to be downloaded over FTP or HTTP.
7249 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
7250 the GNU mirrors defined in @code{(guix download)}.
7252 The @code{sha256} field specifies the expected SHA256 hash of the file
7253 being downloaded. It is mandatory, and allows Guix to check the
7254 integrity of the file. The @code{(base32 @dots{})} form introduces the
7255 base32 representation of the hash. You can obtain this information with
7256 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
7257 hash} (@pxref{Invoking guix hash}).
7260 When needed, the @code{origin} form can also have a @code{patches} field
7261 listing patches to be applied, and a @code{snippet} field giving a
7262 Scheme expression to modify the source code.
7265 @cindex GNU Build System
7266 The @code{build-system} field specifies the procedure to build the
7267 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
7268 represents the familiar GNU Build System, where packages may be
7269 configured, built, and installed with the usual @code{./configure &&
7270 make && make check && make install} command sequence.
7272 When you start packaging non-trivial software, you may need tools to
7273 manipulate those build phases, manipulate files, and so on. @xref{Build
7274 Utilities}, for more on this.
7277 The @code{arguments} field specifies options for the build system
7278 (@pxref{Build Systems}). Here it is interpreted by
7279 @code{gnu-build-system} as a request run @file{configure} with the
7280 @option{--enable-silent-rules} flag.
7286 @cindex backquote (quasiquote)
7289 @cindex comma (unquote)
7292 What about these quote (@code{'}) characters? They are Scheme syntax to
7293 introduce a literal list; @code{'} is synonymous with @code{quote}.
7294 Sometimes you'll also see @code{`} (a backquote, synonymous with
7295 @code{quasiquote}) and @code{,} (a comma, synonymous with @code{unquote}).
7296 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
7297 for details. Here the value of the @code{arguments} field is a list of
7298 arguments passed to the build system down the road, as with @code{apply}
7299 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
7302 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
7303 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
7304 @code{#:configure-flags} is a keyword used to pass a keyword argument
7305 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
7309 The @code{inputs} field specifies inputs to the build process---i.e.,
7310 build-time or run-time dependencies of the package. Here, we add
7311 an input, a reference to the @code{gawk}
7312 variable; @code{gawk} is itself bound to a @code{<package>} object.
7314 Note that GCC, Coreutils, Bash, and other essential tools do not need to
7315 be specified as inputs here. Instead, @code{gnu-build-system} takes care
7316 of ensuring that they are present (@pxref{Build Systems}).
7318 However, any other dependencies need to be specified in the
7319 @code{inputs} field. Any dependency not specified here will simply be
7320 unavailable to the build process, possibly leading to a build failure.
7323 @xref{package Reference}, for a full description of possible fields.
7325 @quotation Going further
7326 @cindex Scheme programming language, getting started
7327 Intimidated by the Scheme language or curious about it? The Cookbook
7328 has a short section to get started that recaps some of the things shown
7329 above and explains the fundamentals. @xref{A Scheme Crash Course,,,
7330 guix-cookbook, GNU Guix Cookbook}, for more information.
7333 Once a package definition is in place, the
7334 package may actually be built using the @code{guix build} command-line
7335 tool (@pxref{Invoking guix build}), troubleshooting any build failures
7336 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
7337 package definition using the @command{guix edit} command
7338 (@pxref{Invoking guix edit}).
7339 @xref{Packaging Guidelines}, for
7340 more information on how to test package definitions, and
7341 @ref{Invoking guix lint}, for information on how to check a definition
7342 for style conformance.
7343 @vindex GUIX_PACKAGE_PATH
7344 Lastly, @pxref{Channels}, for information
7345 on how to extend the distribution by adding your own package definitions
7348 Finally, updating the package definition to a new upstream version
7349 can be partly automated by the @command{guix refresh} command
7350 (@pxref{Invoking guix refresh}).
7352 Behind the scenes, a derivation corresponding to the @code{<package>}
7353 object is first computed by the @code{package-derivation} procedure.
7354 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
7355 The build actions it prescribes may then be realized by using the
7356 @code{build-derivations} procedure (@pxref{The Store}).
7358 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
7359 Return the @code{<derivation>} object of @var{package} for @var{system}
7360 (@pxref{Derivations}).
7362 @var{package} must be a valid @code{<package>} object, and @var{system}
7363 must be a string denoting the target system type---e.g.,
7364 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
7365 must be a connection to the daemon, which operates on the store
7366 (@pxref{The Store}).
7370 @cindex cross-compilation
7371 Similarly, it is possible to compute a derivation that cross-builds a
7372 package for some other system:
7374 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
7375 @var{package} @var{target} [@var{system}]
7376 Return the @code{<derivation>} object of @var{package} cross-built from
7377 @var{system} to @var{target}.
7379 @var{target} must be a valid GNU triplet denoting the target hardware
7380 and operating system, such as @code{"aarch64-linux-gnu"}
7381 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
7384 Once you have package definitions, you can easily define @emph{variants}
7385 of those packages. @xref{Defining Package Variants}, for more on that.
7388 * package Reference:: The package data type.
7389 * origin Reference:: The origin data type.
7393 @node package Reference
7394 @subsection @code{package} Reference
7396 This section summarizes all the options available in @code{package}
7397 declarations (@pxref{Defining Packages}).
7399 @deftp {Data Type} package
7400 This is the data type representing a package recipe.
7404 The name of the package, as a string.
7406 @item @code{version}
7407 The version of the package, as a string. @xref{Version Numbers}, for
7411 An object telling how the source code for the package should be
7412 acquired. Most of the time, this is an @code{origin} object, which
7413 denotes a file fetched from the Internet (@pxref{origin Reference}). It
7414 can also be any other ``file-like'' object such as a @code{local-file},
7415 which denotes a file from the local file system (@pxref{G-Expressions,
7416 @code{local-file}}).
7418 @item @code{build-system}
7419 The build system that should be used to build the package (@pxref{Build
7422 @item @code{arguments} (default: @code{'()})
7423 The arguments that should be passed to the build system (@pxref{Build
7424 Systems}). This is a list, typically containing sequential
7425 keyword-value pairs, as in this example:
7430 ;; several fields omitted
7432 (list #:tests? #f ;skip tests
7433 #:make-flags #~'("VERBOSE=1") ;pass flags to 'make'
7434 #:configure-flags #~'("--enable-frobbing"))))
7437 The exact set of supported keywords depends on the build system
7438 (@pxref{Build Systems}), but you will find that almost all of them honor
7439 @code{#:configure-flags}, @code{#:make-flags}, @code{#:tests?}, and
7440 @code{#:phases}. The @code{#:phases} keyword in particular lets you
7441 modify the set of build phases for your package (@pxref{Build Phases}).
7443 @item @code{inputs} (default: @code{'()})
7444 @itemx @code{native-inputs} (default: @code{'()})
7445 @itemx @code{propagated-inputs} (default: @code{'()})
7446 @cindex inputs, of packages
7447 These fields list dependencies of the package. Each element of these
7448 lists is either a package, origin, or other ``file-like object''
7449 (@pxref{G-Expressions}); to specify the output of that file-like object
7450 that should be used, pass a two-element list where the second element is
7451 the output (@pxref{Packages with Multiple Outputs}, for more on package
7452 outputs). For example, the list below specifies three inputs:
7455 (list libffi libunistring
7456 `(,glib "bin")) ;the "bin" output of GLib
7459 In the example above, the @code{"out"} output of @code{libffi} and
7460 @code{libunistring} is used.
7462 @quotation Compatibility Note
7463 Until version 1.3.0, input lists were a list of tuples,
7464 where each tuple has a label for the input (a string) as its
7465 first element, a package, origin, or derivation as its second element,
7466 and optionally the name of the output thereof that should be used, which
7467 defaults to @code{"out"}. For example, the list below is equivalent to
7468 the one above, but using the @dfn{old input style}:
7471 ;; Old input style (deprecated).
7472 `(("libffi" ,libffi)
7473 ("libunistring" ,libunistring)
7474 ("glib:bin" ,glib "bin")) ;the "bin" output of GLib
7477 This style is now deprecated; it is still supported but support will be
7478 removed in a future version. It should not be used for new package
7479 definitions. @xref{Invoking guix style}, on how to migrate to the new
7483 @cindex cross compilation, package dependencies
7484 The distinction between @code{native-inputs} and @code{inputs} is
7485 necessary when considering cross-compilation. When cross-compiling,
7486 dependencies listed in @code{inputs} are built for the @emph{target}
7487 architecture; conversely, dependencies listed in @code{native-inputs}
7488 are built for the architecture of the @emph{build} machine.
7490 @code{native-inputs} is typically used to list tools needed at
7491 build time, but not at run time, such as Autoconf, Automake, pkg-config,
7492 Gettext, or Bison. @command{guix lint} can report likely mistakes in
7493 this area (@pxref{Invoking guix lint}).
7495 @anchor{package-propagated-inputs}
7496 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
7497 specified packages will be automatically installed to profiles
7498 (@pxref{Features, the role of profiles in Guix}) alongside the package
7499 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
7500 package}}, for information on how @command{guix package} deals with
7503 For example this is necessary when packaging a C/C++ library that needs
7504 headers of another library to compile, or when a pkg-config file refers
7505 to another one @i{via} its @code{Requires} field.
7507 Another example where @code{propagated-inputs} is useful is for languages
7508 that lack a facility to record the run-time search path akin to the
7509 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
7510 more. When packaging libraries written in those languages, ensure they
7511 can find library code they depend on at run time by listing run-time
7512 dependencies in @code{propagated-inputs} rather than @code{inputs}.
7514 @item @code{outputs} (default: @code{'("out")})
7515 The list of output names of the package. @xref{Packages with Multiple
7516 Outputs}, for typical uses of additional outputs.
7518 @item @code{native-search-paths} (default: @code{'()})
7519 @itemx @code{search-paths} (default: @code{'()})
7520 A list of @code{search-path-specification} objects describing
7521 search-path environment variables honored by the package. @xref{Search
7522 Paths}, for more on search path specifications.
7524 As for inputs, the distinction between @code{native-search-paths} and
7525 @code{search-paths} only matters when cross-compiling. In a
7526 cross-compilation context, @code{native-search-paths} applies
7527 exclusively to native inputs whereas @code{search-paths} applies only to
7530 Packages such as cross-compilers care about target inputs---for
7531 instance, our (modified) GCC cross-compiler has
7532 @env{CROSS_C_INCLUDE_PATH} in @code{search-paths}, which allows it to
7533 pick @file{.h} files for the target system and @emph{not} those of
7534 native inputs. For the majority of packages though, only
7535 @code{native-search-paths} makes sense.
7537 @item @code{replacement} (default: @code{#f})
7538 This must be either @code{#f} or a package object that will be used as a
7539 @dfn{replacement} for this package. @xref{Security Updates, grafts},
7542 @item @code{synopsis}
7543 A one-line description of the package.
7545 @item @code{description}
7546 A more elaborate description of the package, as a string in Texinfo
7549 @item @code{license}
7550 @cindex license, of packages
7551 The license of the package; a value from @code{(guix licenses)},
7552 or a list of such values.
7554 @item @code{home-page}
7555 The URL to the home-page of the package, as a string.
7557 @item @code{supported-systems} (default: @code{%supported-systems})
7558 The list of systems supported by the package, as strings of the form
7559 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
7561 @item @code{location} (default: source location of the @code{package} form)
7562 The source location of the package. It is useful to override this when
7563 inheriting from another package, in which case this field is not
7564 automatically corrected.
7568 @deffn {Scheme Syntax} this-package
7569 When used in the @emph{lexical scope} of a package field definition, this
7570 identifier resolves to the package being defined.
7572 The example below shows how to add a package as a native input of itself when
7580 ;; When cross-compiled, Guile, for example, depends on
7581 ;; a native version of itself. Add it here.
7582 (native-inputs (if (%current-target-system)
7587 It is an error to refer to @code{this-package} outside a package definition.
7590 The following helper procedures are provided to help deal with package
7593 @deffn {Scheme Procedure} lookup-package-input @var{package} @var{name}
7594 @deffnx {Scheme Procedure} lookup-package-native-input @var{package} @var{name}
7595 @deffnx {Scheme Procedure} lookup-package-propagated-input @var{package} @var{name}
7596 @deffnx {Scheme Procedure} lookup-package-direct-input @var{package} @var{name}
7597 Look up @var{name} among @var{package}'s inputs (or native, propagated,
7598 or direct inputs). Return it if found, @code{#f} otherwise.
7600 @var{name} is the name of a package depended on. Here's how you might
7604 (use-modules (guix packages) (gnu packages base))
7606 (lookup-package-direct-input coreutils "gmp")
7607 @result{} #<package gmp@@6.2.1 @dots{}>
7610 In this example we obtain the @code{gmp} package that is among the
7611 direct inputs of @code{coreutils}.
7614 @cindex development inputs, of a package
7615 @cindex implicit inputs, of a package
7616 Sometimes you will want to obtain the list of inputs needed to
7617 @emph{develop} a package---all the inputs that are visible when the
7618 package is compiled. This is what the @code{package-development-inputs}
7621 @deffn {Scheme Procedure} package-development-inputs @var{package} @
7622 [@var{system}] [#:target #f]
7623 Return the list of inputs required by @var{package} for development
7624 purposes on @var{system}. When @var{target} is true, return the inputs
7625 needed to cross-compile @var{package} from @var{system} to
7626 @var{target}, where @var{target} is a triplet such as
7627 @code{"aarch64-linux-gnu"}.
7629 Note that the result includes both explicit inputs and implicit
7630 inputs---inputs automatically added by the build system (@pxref{Build
7631 Systems}). Let us take the @code{hello} package to illustrate that:
7634 (use-modules (gnu packages base) (guix packages))
7637 @result{} #<package hello@@2.10 gnu/packages/base.scm:79 7f585d4f6790>
7639 (package-direct-inputs hello)
7642 (package-development-inputs hello)
7643 @result{} (("source" @dots{}) ("tar" #<package tar@@1.32 @dots{}>) @dots{})
7646 In this example, @code{package-direct-inputs} returns the empty list,
7647 because @code{hello} has zero explicit dependencies. Conversely,
7648 @code{package-development-inputs} includes inputs implicitly added by
7649 @code{gnu-build-system} that are required to build @code{hello}: tar,
7650 gzip, GCC, libc, Bash, and more. To visualize it, @command{guix graph
7651 hello} would show you explicit inputs, whereas @command{guix graph -t
7652 bag hello} would include implicit inputs (@pxref{Invoking guix graph}).
7655 Because packages are regular Scheme objects that capture a complete
7656 dependency graph and associated build procedures, it is often useful to
7657 write procedures that take a package and return a modified version
7658 thereof according to some parameters. Below are a few examples.
7660 @cindex tool chain, choosing a package's tool chain
7661 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
7662 Return a variant of @var{package} that uses @var{toolchain} instead of
7663 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
7664 inputs (label/package tuples) providing equivalent functionality, such
7665 as the @code{gcc-toolchain} package.
7667 The example below returns a variant of the @code{hello} package built
7668 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
7669 GNU C Library) instead of the default tool chain:
7672 (let ((toolchain (specification->package "gcc-toolchain@@10")))
7673 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
7676 The build tool chain is part of the @dfn{implicit inputs} of
7677 packages---it's usually not listed as part of the various ``inputs''
7678 fields and is instead pulled in by the build system. Consequently, this
7679 procedure works by changing the build system of @var{package} so that it
7680 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
7681 for more on build systems.
7684 @node origin Reference
7685 @subsection @code{origin} Reference
7687 This section documents @dfn{origins}. An @code{origin} declaration
7688 specifies data that must be ``produced''---downloaded, usually---and
7689 whose content hash is known in advance. Origins are primarily used to
7690 represent the source code of packages (@pxref{Defining Packages}). For
7691 that reason, the @code{origin} form allows you to declare patches to
7692 apply to the original source code as well as code snippets to modify it.
7694 @deftp {Data Type} origin
7695 This is the data type representing a source code origin.
7699 An object containing the URI of the source. The object type depends on
7700 the @code{method} (see below). For example, when using the
7701 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
7702 values are: a URL represented as a string, or a list thereof.
7704 @cindex fixed-output derivations, for download
7706 A monadic procedure that handles the given URI@. The procedure must
7707 accept at least three arguments: the value of the @code{uri} field and
7708 the hash algorithm and hash value specified by the @code{hash} field.
7709 It must return a store item or a derivation in the store monad
7710 (@pxref{The Store Monad}); most methods return a fixed-output derivation
7711 (@pxref{Derivations}).
7713 Commonly used methods include @code{url-fetch}, which fetches data from
7714 a URL, and @code{git-fetch}, which fetches data from a Git repository
7718 A bytevector containing the SHA-256 hash of the source. This is
7719 equivalent to providing a @code{content-hash} SHA256 object in the
7720 @code{hash} field described below.
7723 The @code{content-hash} object of the source---see below for how to use
7724 @code{content-hash}.
7726 You can obtain this information using @code{guix download}
7727 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
7730 @item @code{file-name} (default: @code{#f})
7731 The file name under which the source code should be saved. When this is
7732 @code{#f}, a sensible default value will be used in most cases. In case
7733 the source is fetched from a URL, the file name from the URL will be
7734 used. For version control checkouts, it is recommended to provide the
7735 file name explicitly because the default is not very descriptive.
7737 @item @code{patches} (default: @code{'()})
7738 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
7739 file-like objects}) pointing to patches to be applied to the source.
7741 This list of patches must be unconditional. In particular, it cannot
7742 depend on the value of @code{%current-system} or
7743 @code{%current-target-system}.
7745 @item @code{snippet} (default: @code{#f})
7746 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
7747 in the source directory. This is a convenient way to modify the source,
7748 sometimes more convenient than a patch.
7750 @item @code{patch-flags} (default: @code{'("-p1")})
7751 A list of command-line flags that should be passed to the @code{patch}
7754 @item @code{patch-inputs} (default: @code{#f})
7755 Input packages or derivations to the patching process. When this is
7756 @code{#f}, the usual set of inputs necessary for patching are provided,
7757 such as GNU@tie{}Patch.
7759 @item @code{modules} (default: @code{'()})
7760 A list of Guile modules that should be loaded during the patching
7761 process and while running the code in the @code{snippet} field.
7763 @item @code{patch-guile} (default: @code{#f})
7764 The Guile package that should be used in the patching process. When
7765 this is @code{#f}, a sensible default is used.
7769 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
7770 Construct a content hash object for the given @var{algorithm}, and with
7771 @var{value} as its hash value. When @var{algorithm} is omitted, assume
7772 it is @code{sha256}.
7774 @var{value} can be a literal string, in which case it is base32-decoded,
7775 or it can be a bytevector.
7777 The following forms are all equivalent:
7780 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
7781 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
7783 (content-hash (base32
7784 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
7785 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
7789 Technically, @code{content-hash} is currently implemented as a macro.
7790 It performs sanity checks at macro-expansion time, when possible, such
7791 as ensuring that @var{value} has the right size for @var{algorithm}.
7794 As we have seen above, how exactly the data an origin refers to is
7795 retrieved is determined by its @code{method} field. The @code{(guix
7796 download)} module provides the most common method, @code{url-fetch},
7799 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
7800 [name] [#:executable? #f]
7801 Return a fixed-output derivation that fetches data from @var{url} (a
7802 string, or a list of strings denoting alternate URLs), which is expected
7803 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
7804 the file name is the base name of URL; optionally, @var{name} can
7805 specify a different file name. When @var{executable?} is true, make the
7806 downloaded file executable.
7808 When one of the URL starts with @code{mirror://}, then its host part is
7809 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
7811 Alternatively, when URL starts with @code{file://}, return the
7812 corresponding file name in the store.
7815 Likewise, the @code{(guix git-download)} module defines the
7816 @code{git-fetch} origin method, which fetches data from a Git version
7817 control repository, and the @code{git-reference} data type to describe
7818 the repository and revision to fetch.
7820 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
7821 Return a fixed-output derivation that fetches @var{ref}, a
7822 @code{<git-reference>} object. The output is expected to have recursive
7823 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7824 the file name, or a generic name if @code{#f}.
7827 @deftp {Data Type} git-reference
7828 This data type represents a Git reference for @code{git-fetch} to
7833 The URL of the Git repository to clone.
7836 This string denotes either the commit to fetch (a hexadecimal string),
7837 or the tag to fetch. You can also use a ``short'' commit ID or a
7838 @command{git describe} style identifier such as
7839 @code{v1.0.1-10-g58d7909c97}.
7841 @item @code{recursive?} (default: @code{#f})
7842 This Boolean indicates whether to recursively fetch Git sub-modules.
7845 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
7850 (url "https://git.savannah.gnu.org/git/hello.git")
7854 This is equivalent to the reference below, which explicitly names the
7859 (url "https://git.savannah.gnu.org/git/hello.git")
7860 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
7864 For Mercurial repositories, the module @code{(guix hg-download)} defines
7865 the @code{hg-fetch} origin method and @code{hg-reference} data type for
7866 support of the Mercurial version control system.
7868 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
7870 Return a fixed-output derivation that fetches @var{ref}, a
7871 @code{<hg-reference>} object. The output is expected to have recursive
7872 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7873 the file name, or a generic name if @code{#false}.
7876 @node Defining Package Variants
7877 @section Defining Package Variants
7879 @cindex customizing packages
7880 @cindex variants, of packages
7881 One of the nice things with Guix is that, given a package definition,
7882 you can easily @emph{derive} variants of that package---for a different
7883 upstream version, with different dependencies, different compilation
7884 options, and so on. Some of these custom packages can be defined
7885 straight from the command line (@pxref{Package Transformation Options}).
7886 This section describes how to define package variants in code. This can
7887 be useful in ``manifests'' (@pxref{Writing Manifests})
7888 and in your own package collection
7889 (@pxref{Creating a Channel}), among others!
7891 @cindex inherit, for package definitions
7892 As discussed earlier, packages are first-class objects in the Scheme
7893 language. The @code{(guix packages)} module provides the @code{package}
7894 construct to define new package objects (@pxref{package Reference}).
7895 The easiest way to define a package variant is using the @code{inherit}
7896 keyword together with @code{package}. This allows you to inherit from a
7897 package definition while overriding the fields you want.
7899 For example, given the @code{hello} variable, which contains a
7900 definition for the current version of GNU@tie{}Hello, here's how you
7901 would define a variant for version 2.2 (released in 2006, it's
7905 (use-modules (gnu packages base)) ;for 'hello'
7913 (uri (string-append "mirror://gnu/hello/hello-" version
7917 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
7920 The example above corresponds to what the @option{--with-source} package
7921 transformation option does. Essentially @code{hello-2.2} preserves all
7922 the fields of @code{hello}, except @code{version} and @code{source},
7923 which it overrides. Note that the original @code{hello} variable is
7924 still there, in the @code{(gnu packages base)} module, unchanged. When
7925 you define a custom package like this, you are really @emph{adding} a
7926 new package definition; the original one remains available.
7928 You can just as well define variants with a different set of
7929 dependencies than the original package. For example, the default
7930 @code{gdb} package depends on @code{guile}, but since that is an
7931 optional dependency, you can define a variant that removes that
7935 (use-modules (gnu packages gdb)) ;for 'gdb'
7937 (define gdb-sans-guile
7940 (inputs (modify-inputs (package-inputs gdb)
7941 (delete "guile")))))
7944 The @code{modify-inputs} form above removes the @code{"guile"} package
7945 from the @code{inputs} field of @code{gdb}. The @code{modify-inputs}
7946 macro is a helper that can prove useful anytime you want to remove, add,
7947 or replace package inputs.
7949 @deffn {Scheme Syntax} modify-inputs @var{inputs} @var{clauses}
7950 Modify the given package inputs, as returned by @code{package-inputs} & co.,
7951 according to the given clauses. Each clause must have one of the
7955 @item (delete @var{name}@dots{})
7956 Delete from the inputs packages with the given @var{name}s (strings).
7958 @item (append @var{package}@dots{})
7959 Add @var{package}s to the end of the input list.
7961 @item (prepend @var{package}@dots{})
7962 Add @var{package}s to the front of the input list.
7965 The example below removes the GMP and ACL inputs of Coreutils and adds
7966 libcap to the back of the input list:
7969 (modify-inputs (package-inputs coreutils)
7970 (delete "gmp" "acl")
7974 The example below replaces the @code{guile} package from the inputs of
7975 @code{guile-redis} with @code{guile-2.2}:
7978 (modify-inputs (package-inputs guile-redis)
7979 (replace "guile" guile-2.2))
7982 The last type of clause is @code{prepend}, to add inputs to the front of
7986 In some cases, you may find it useful to write functions
7987 (``procedures'', in Scheme parlance) that return a package based on some
7988 parameters. For example, consider the @code{luasocket} library for the
7989 Lua programming language. We want to create @code{luasocket} packages
7990 for major versions of Lua. One way to do that is to define a procedure
7991 that takes a Lua package and returns a @code{luasocket} package that
7995 (define (make-lua-socket name lua)
7996 ;; Return a luasocket package built with LUA.
8000 ;; several fields omitted
8002 (synopsis "Socket library for Lua")))
8004 (define-public lua5.1-socket
8005 (make-lua-socket "lua5.1-socket" lua-5.1))
8007 (define-public lua5.2-socket
8008 (make-lua-socket "lua5.2-socket" lua-5.2))
8011 Here we have defined packages @code{lua5.1-socket} and
8012 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
8013 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
8014 more info on procedures. Having top-level public definitions for these
8015 two packages means that they can be referred to from the command line
8016 (@pxref{Package Modules}).
8018 @cindex package transformations
8019 These are pretty simple package variants. As a convenience, the
8020 @code{(guix transformations)} module provides a high-level interface
8021 that directly maps to the more sophisticated package transformation
8022 options (@pxref{Package Transformation Options}):
8024 @deffn {Scheme Procedure} options->transformation @var{opts}
8025 Return a procedure that, when passed an object to build (package,
8026 derivation, etc.), applies the transformations specified by @var{opts} and returns
8027 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
8030 ((with-branch . "guile-gcrypt=master")
8031 (without-tests . "libgcrypt"))
8034 Each symbol names a transformation and the corresponding string is an argument
8035 to that transformation.
8038 For instance, a manifest equivalent to this command:
8042 --with-branch=guile-gcrypt=master \
8043 --with-debug-info=zlib
8047 ... would look like this:
8050 (use-modules (guix transformations))
8053 ;; The package transformation procedure.
8054 (options->transformation
8055 '((with-branch . "guile-gcrypt=master")
8056 (with-debug-info . "zlib"))))
8059 (list (transform (specification->package "guix"))))
8062 @cindex input rewriting
8063 @cindex dependency graph rewriting
8064 The @code{options->transformation} procedure is convenient, but it's
8065 perhaps also not as flexible as you may like. How is it implemented?
8066 The astute reader probably noticed that most package transformation
8067 options go beyond the superficial changes shown in the first examples of
8068 this section: they involve @dfn{input rewriting}, whereby the dependency
8069 graph of a package is rewritten by replacing specific inputs by others.
8071 Dependency graph rewriting, for the purposes of swapping packages in the
8072 graph, is what the @code{package-input-rewriting} procedure in
8073 @code{(guix packages)} implements.
8075 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
8076 [@var{rewrite-name}] [#:deep? #t]
8077 Return a procedure that, when passed a package, replaces its direct and
8078 indirect dependencies, including implicit inputs when @var{deep?} is
8079 true, according to @var{replacements}. @var{replacements} is a list of
8080 package pairs; the first element of each pair is the package to replace,
8081 and the second one is the replacement.
8083 Optionally, @var{rewrite-name} is a one-argument procedure that takes
8084 the name of a package and returns its new name after rewrite.
8088 Consider this example:
8091 (define libressl-instead-of-openssl
8092 ;; This is a procedure to replace OPENSSL by LIBRESSL,
8094 (package-input-rewriting `((,openssl . ,libressl))))
8096 (define git-with-libressl
8097 (libressl-instead-of-openssl git))
8101 Here we first define a rewriting procedure that replaces @var{openssl}
8102 with @var{libressl}. Then we use it to define a @dfn{variant} of the
8103 @var{git} package that uses @var{libressl} instead of @var{openssl}.
8104 This is exactly what the @option{--with-input} command-line option does
8105 (@pxref{Package Transformation Options, @option{--with-input}}).
8107 The following variant of @code{package-input-rewriting} can match packages to
8108 be replaced by name rather than by identity.
8110 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
8111 Return a procedure that, given a package, applies the given
8112 @var{replacements} to all the package graph, including implicit inputs
8113 unless @var{deep?} is false. @var{replacements} is a list of
8114 spec/procedures pair; each spec is a package specification such as
8115 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
8116 package and returns a replacement for that package.
8119 The example above could be rewritten this way:
8122 (define libressl-instead-of-openssl
8123 ;; Replace all the packages called "openssl" with LibreSSL.
8124 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
8127 The key difference here is that, this time, packages are matched by spec and
8128 not by identity. In other words, any package in the graph that is called
8129 @code{openssl} will be replaced.
8131 A more generic procedure to rewrite a package dependency graph is
8132 @code{package-mapping}: it supports arbitrary changes to nodes in the
8135 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
8136 Return a procedure that, given a package, applies @var{proc} to all the packages
8137 depended on and returns the resulting package. The procedure stops recursion
8138 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
8139 applied to implicit inputs as well.
8142 @node Writing Manifests
8143 @section Writing Manifests
8146 @cindex bill of materials (manifests)
8147 @command{guix} commands let you specify package lists on the command
8148 line. This is convenient, but as the command line becomes longer and
8149 less trivial, it quickly becomes more convenient to have that package
8150 list in what we call a @dfn{manifest}. A manifest is some sort of a
8151 ``bill of materials'' that defines a package set. You would typically
8152 come up with a code snippet that builds the manifest, store it in a
8153 file, say @file{manifest.scm}, and then pass that file to the
8154 @option{-m} (or @option{--manifest}) option that many @command{guix}
8155 commands support. For example, here's what a manifest for a simple
8156 package set might look like:
8159 ;; Manifest for three packages.
8160 (specifications->manifest '("gcc-toolchain" "make" "git"))
8163 Once you have that manifest, you can pass it, for example, to
8164 @command{guix package} to install just those three packages to your
8165 profile (@pxref{profile-manifest, @option{-m} option of @command{guix
8169 guix package -m manifest.scm
8173 ... or you can pass it to @command{guix shell} (@pxref{shell-manifest,
8174 @command{-m} option of @command{guix shell}}) to spawn an ephemeral
8178 guix shell -m manifest.scm
8182 ... or you can pass it to @command{guix pack} in pretty much the same
8183 way (@pxref{pack-manifest, @option{-m} option of @command{guix pack}}).
8184 You can store the manifest under version control, share it with others
8185 so they can easily get set up, etc.
8187 But how do you write your first manifest? To get started, maybe you'll
8188 want to write a manifest that mirrors what you already have in a
8189 profile. Rather than start from a blank page, @command{guix package}
8190 can generate a manifest for you (@pxref{export-manifest, @command{guix
8191 package --export-manifest}}):
8194 # Write to 'manifest.scm' a manifest corresponding to the
8195 # default profile, ~/.guix-profile.
8196 guix package --export-manifest > manifest.scm
8199 Or maybe you'll want to ``translate'' command-line arguments into a
8200 manifest. In that case, @command{guix shell} can help
8201 (@pxref{shell-export-manifest, @command{guix shell --export-manifest}}):
8204 # Write a manifest for the packages specified on the command line.
8205 guix shell --export-manifest gcc-toolchain make git > manifest.scm
8208 In both cases, the @option{--export-manifest} option tries hard to
8209 generate a faithful manifest; in particular, it takes package
8210 transformation options into account (@pxref{Package Transformation
8214 Manifests are @emph{symbolic}: they refer to packages of the channels
8215 @emph{currently in use} (@pxref{Channels}). In the example above,
8216 @code{gcc-toolchain} might refer to version 11 today, but it might refer
8217 to version 13 two years from now.
8219 If you want to ``pin'' your software environment to specific package
8220 versions and variants, you need an additional piece of information: the
8221 list of channel revisions in use, as returned by @command{guix
8222 describe}. @xref{Replicating Guix}, for more information.
8225 Once you've obtained your first manifest, perhaps you'll want to
8226 customize it. Since your manifest is code, you now have access to all
8227 the Guix programming interfaces!
8229 Let's assume you want a manifest to deploy a custom variant of GDB, the
8230 GNU Debugger, that does not depend on Guile, together with another
8231 package. Building on the example seen in the previous section
8232 (@pxref{Defining Package Variants}), you can write a manifest along
8236 (use-modules (guix packages)
8237 (gnu packages gdb) ;for 'gdb'
8238 (gnu packages version-control)) ;for 'git'
8240 ;; Define a variant of GDB without a dependency on Guile.
8241 (define gdb-sans-guile
8244 (inputs (modify-inputs (package-inputs gdb)
8245 (delete "guile")))))
8247 ;; Return a manifest containing that one package plus Git.
8248 (packages->manifest (list gdb-sans-guile git))
8251 Note that in this example, the manifest directly refers to the
8252 @code{gdb} and @code{git} variables, which are bound to a @code{package}
8253 object (@pxref{package Reference}), instead of calling
8254 @code{specifications->manifest} to look up packages by name as we did
8255 before. The @code{use-modules} form at the top lets us access the core
8256 package interface (@pxref{Defining Packages}) and the modules that
8257 define @code{gdb} and @code{git} (@pxref{Package Modules}). Seamlessly,
8258 we're weaving all this together---the possibilities are endless, unleash
8261 The data type for manifests as well as supporting procedures are defined
8262 in the @code{(guix profiles)} module, which is automatically available
8263 to code passed to @option{-m}. The reference follows.
8265 @deftp {Data Type} manifest
8266 Data type representing a manifest.
8268 It currently has one field:
8272 This must be a list of @code{manifest-entry} records---see below.
8276 @deftp {Data Type} manifest-entry
8277 Data type representing a manifest entry. A manifest entry contains
8278 essential metadata: a name and version string, the object (usually a
8279 package) for that entry, the desired output (@pxref{Packages with
8280 Multiple Outputs}), and a number of optional pieces of information
8283 Most of the time, you won't build a manifest entry directly; instead,
8284 you will pass a package to @code{package->manifest-entry}, described
8285 below. In some unusual cases though, you might want to create manifest
8286 entries for things that are @emph{not} packages, as in this example:
8289 ;; Manually build a single manifest entry for a non-package object.
8290 (let ((hello (program-file "hello" #~(display "Hi!"))))
8295 (computed-file "hello-directory"
8296 #~(let ((bin (string-append #$output "/bin")))
8297 (mkdir #$output) (mkdir bin)
8299 (string-append bin "/hello")))))))
8302 The available fields are the following:
8306 @itemx @code{version}
8307 Name and version string for this entry.
8310 A package or other file-like object (@pxref{G-Expressions, file-like
8313 @item @code{output} (default: @code{"out"})
8314 Output of @code{item} to use, in case @code{item} has multiple outputs
8315 (@pxref{Packages with Multiple Outputs}).
8317 @item @code{dependencies} (default: @code{'()})
8318 List of manifest entries this entry depends on. When building a
8319 profile, dependencies are added to the profile.
8321 Typically, the propagated inputs of a package (@pxref{package Reference,
8322 @code{propagated-inputs}}) end up having a corresponding manifest entry
8323 in among the dependencies of the package's own manifest entry.
8325 @item @code{search-paths} (default: @code{'()})
8326 The list of search path specifications honored by this entry
8327 (@pxref{Search Paths}).
8329 @item @code{properties} (default: @code{'()})
8330 List of symbol/value pairs. When building a profile, those properties
8333 This can be used to piggyback additional metadata---e.g., the
8334 transformations applied to a package (@pxref{Package Transformation
8337 @item @code{parent} (default: @code{(delay #f)})
8338 A promise pointing to the ``parent'' manifest entry.
8340 This is used as a hint to provide context when reporting an error
8341 related to a manifest entry coming from a @code{dependencies} field.
8345 @deffn {Scheme Procedure} concatenate-manifests @var{lst}
8346 Concatenate the manifests listed in @var{lst} and return the resulting
8350 @c TODO: <manifest-pattern>, manifest-lookup, manifest-remove, etc.
8352 @deffn {Scheme Procedure} package->manifest-entry @var{package} @
8353 [@var{output}] [#:properties]
8354 Return a manifest entry for the @var{output} of package @var{package},
8355 where @var{output} defaults to @code{"out"}, and with the given
8356 @var{properties}. By default @var{properties} is the empty list or, if
8357 one or more package transformations were applied to @var{package}, it is
8358 an association list representing those transformations, suitable as an
8359 argument to @code{options->transformation} (@pxref{Defining Package
8360 Variants, @code{options->transformation}}).
8362 The code snippet below builds a manifest with an entry for the default
8363 output and the @code{send-email} output of the @code{git} package:
8366 (use-modules (gnu packages version-control))
8368 (manifest (list (package->manifest-entry git)
8369 (package->manifest-entry git "send-email")))
8373 @deffn {Scheme Procedure} packages->manifest @var{packages}
8374 Return a list of manifest entries, one for each item listed in
8375 @var{packages}. Elements of @var{packages} can be either package
8376 objects or package/string tuples denoting a specific output of a
8379 Using this procedure, the manifest above may be rewritten more
8383 (use-modules (gnu packages version-control))
8385 (packages->manifest (list git `(,git "send-email")))
8389 @anchor{package-development-manifest}
8390 @deffn {Scheme Procedure} package->development-manifest @var{package} @
8391 [@var{system}] [#:target]
8392 Return a manifest for the @dfn{development inputs} of @var{package} for
8393 @var{system}, optionally when cross-compiling to @var{target}.
8394 Development inputs include both explicit and implicit inputs of
8397 Like the @option{-D} option of @command{guix shell}
8398 (@pxref{shell-development-option, @command{guix shell -D}}), the
8399 resulting manifest describes the environment in which one can develop
8400 @var{package}. For example, suppose you're willing to set up a
8401 development environment for Inkscape, with the addition of Git for
8402 version control; you can describe that ``bill of materials'' with the
8406 (use-modules (gnu packages inkscape) ;for 'inkscape'
8407 (gnu packages version-control)) ;for 'git'
8409 (concatenate-manifests
8410 (list (package->development-manifest inkscape)
8411 (packages->manifest (list git))))
8414 In this example, the development manifest that
8415 @code{package->development-manifest} returns includes the compiler
8416 (GCC), the many supporting libraries (Boost, GLib, GTK, etc.), and a
8417 couple of additional development tools---these are the dependencies
8418 @command{guix show inkscape} lists.
8421 @c TODO: Move (gnu packages) interface to a section of its own.
8423 Last, the @code{(gnu packages)} module provides higher-level facilities
8424 to build manifests. In particular, it lets you look up packages by
8427 @deffn {Scheme Procedure} specifications->manifest @var{specs}
8428 Given @var{specs}, a list of specifications such as @code{"emacs@@25.2"}
8429 or @code{"guile:debug"}, return a manifest. Specs have the format that
8430 command-line tools such as @command{guix install} and @command{guix
8431 package} understand (@pxref{Invoking guix package}).
8433 As an example, it lets you rewrite the Git manifest that we saw earlier
8437 (specifications->manifest '("git" "git:send-email"))
8440 Notice that we do not need to worry about @code{use-modules}, importing
8441 the right set of modules, and referring to the right variables.
8442 Instead, we directly refer to packages in the same way as on the command
8443 line, which can often be more convenient.
8446 @c TODO: specifications->package, etc.
8450 @section Build Systems
8452 @cindex build system
8453 Each package definition specifies a @dfn{build system} and arguments for
8454 that build system (@pxref{Defining Packages}). This @code{build-system}
8455 field represents the build procedure of the package, as well as implicit
8456 dependencies of that build procedure.
8458 Build systems are @code{<build-system>} objects. The interface to
8459 create and manipulate them is provided by the @code{(guix build-system)}
8460 module, and actual build systems are exported by specific modules.
8462 @cindex bag (low-level package representation)
8463 Under the hood, build systems first compile package objects to
8464 @dfn{bags}. A @dfn{bag} is like a package, but with less
8465 ornamentation---in other words, a bag is a lower-level representation of
8466 a package, which includes all the inputs of that package, including some
8467 that were implicitly added by the build system. This intermediate
8468 representation is then compiled to a derivation (@pxref{Derivations}).
8469 The @code{package-with-c-toolchain} is an example of a way to change the
8470 implicit inputs that a package's build system pulls in (@pxref{package
8471 Reference, @code{package-with-c-toolchain}}).
8473 Build systems accept an optional list of @dfn{arguments}. In package
8474 definitions, these are passed @i{via} the @code{arguments} field
8475 (@pxref{Defining Packages}). They are typically keyword arguments
8476 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
8477 Guile Reference Manual}). The value of these arguments is usually
8478 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
8479 by the daemon (@pxref{Derivations}).
8481 The main build system is @code{gnu-build-system}, which implements the
8482 standard build procedure for GNU and many other packages. It
8483 is provided by the @code{(guix build-system gnu)} module.
8485 @defvr {Scheme Variable} gnu-build-system
8486 @code{gnu-build-system} represents the GNU Build System, and variants
8487 thereof (@pxref{Configuration, configuration and makefile conventions,,
8488 standards, GNU Coding Standards}).
8490 @cindex build phases
8491 In a nutshell, packages using it are configured, built, and installed with
8492 the usual @code{./configure && make && make check && make install}
8493 command sequence. In practice, a few additional steps are often needed.
8494 All these steps are split up in separate @dfn{phases}.
8495 @xref{Build Phases}, for more info on build phases and ways to customize
8498 In addition, this build system ensures that the ``standard'' environment
8499 for GNU packages is available. This includes tools such as GCC, libc,
8500 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
8501 build-system gnu)} module for a complete list). We call these the
8502 @dfn{implicit inputs} of a package, because package definitions do not
8503 have to mention them.
8505 This build system supports a number of keyword arguments, which can be
8506 passed @i{via} the @code{arguments} field of a package. Here are some
8507 of the main parameters:
8511 This argument specifies build-side code that evaluates to an alist of
8512 build phases. @xref{Build Phases}, for more information.
8514 @item #:configure-flags
8515 This is a list of flags (strings) passed to the @command{configure}
8516 script. @xref{Defining Packages}, for an example.
8519 This list of strings contains flags passed as arguments to
8520 @command{make} invocations in the @code{build}, @code{check}, and
8521 @code{install} phases.
8523 @item #:out-of-source?
8524 This Boolean, @code{#f} by default, indicates whether to run builds in a
8525 build directory separate from the source tree.
8527 When it is true, the @code{configure} phase creates a separate build
8528 directory, changes to that directory, and runs the @code{configure}
8529 script from there. This is useful for packages that require it, such as
8533 This Boolean, @code{#t} by default, indicates whether the @code{check}
8534 phase should run the package's test suite.
8537 This string, @code{"check"} by default, gives the name of the makefile
8538 target used by the @code{check} phase.
8540 @item #:parallel-build?
8541 @itemx #:parallel-tests?
8542 These Boolean values specify whether to build, respectively run the test
8543 suite, in parallel, with the @code{-j} flag of @command{make}. When
8544 they are true, @code{make} is passed @code{-j@var{n}}, where @var{n} is
8545 the number specified as the @option{--cores} option of
8546 @command{guix-daemon} or that of the @command{guix} client command
8547 (@pxref{Common Build Options, @option{--cores}}).
8549 @cindex RUNPATH, validation
8550 @item #:validate-runpath?
8551 This Boolean, @code{#t} by default, determines whether to ``validate''
8552 the @code{RUNPATH} of ELF binaries (@code{.so} shared libraries as well
8553 as executables) previously installed by the @code{install} phase.
8554 @xref{phase-validate-runpath, the @code{validate-runpath} phase}, for
8557 @item #:substitutable?
8558 This Boolean, @code{#t} by default, tells whether the package outputs
8559 should be substitutable---i.e., whether users should be able to obtain
8560 substitutes for them instead of building locally (@pxref{Substitutes}).
8562 @item #:allowed-references
8563 @itemx #:disallowed-references
8564 When true, these arguments must be a list of dependencies that must not
8565 appear among the references of the build results. If, upon build
8566 completion, some of these references are retained, the build process
8569 This is useful to ensure that a package does not erroneously keep a
8570 reference to some of it build-time inputs, in cases where doing so
8571 would, for example, unnecessarily increase its size (@pxref{Invoking
8575 Most other build systems support these keyword arguments.
8578 Other @code{<build-system>} objects are defined to support other
8579 conventions and tools used by free software packages. They inherit most
8580 of @code{gnu-build-system}, and differ mainly in the set of inputs
8581 implicitly added to the build process, and in the list of phases
8582 executed. Some of these build systems are listed below.
8584 @defvr {Scheme Variable} ant-build-system
8585 This variable is exported by @code{(guix build-system ant)}. It
8586 implements the build procedure for Java packages that can be built with
8587 @url{https://ant.apache.org/, Ant build tool}.
8589 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
8590 provided by the @code{icedtea} package to the set of inputs. Different
8591 packages can be specified with the @code{#:ant} and @code{#:jdk}
8592 parameters, respectively.
8594 When the original package does not provide a suitable Ant build file,
8595 the parameter @code{#:jar-name} can be used to generate a minimal Ant
8596 build file @file{build.xml} with tasks to build the specified jar
8597 archive. In this case the parameter @code{#:source-dir} can be used to
8598 specify the source sub-directory, defaulting to ``src''.
8600 The @code{#:main-class} parameter can be used with the minimal ant
8601 buildfile to specify the main class of the resulting jar. This makes the
8602 jar file executable. The @code{#:test-include} parameter can be used to
8603 specify the list of junit tests to run. It defaults to
8604 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
8605 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
8606 because abstract classes cannot be run as tests.
8608 The parameter @code{#:build-target} can be used to specify the Ant task
8609 that should be run during the @code{build} phase. By default the
8610 ``jar'' task will be run.
8614 @defvr {Scheme Variable} android-ndk-build-system
8615 @cindex Android distribution
8616 @cindex Android NDK build system
8617 This variable is exported by @code{(guix build-system android-ndk)}. It
8618 implements a build procedure for Android NDK (native development kit)
8619 packages using a Guix-specific build process.
8621 The build system assumes that packages install their public interface
8622 (header) files to the subdirectory @file{include} of the @code{out} output and
8623 their libraries to the subdirectory @file{lib} the @code{out} output.
8625 It's also assumed that the union of all the dependencies of a package
8626 has no conflicting files.
8628 For the time being, cross-compilation is not supported - so right now
8629 the libraries and header files are assumed to be host tools.
8633 @defvr {Scheme Variable} asdf-build-system/source
8634 @defvrx {Scheme Variable} asdf-build-system/sbcl
8635 @defvrx {Scheme Variable} asdf-build-system/ecl
8637 These variables, exported by @code{(guix build-system asdf)}, implement
8638 build procedures for Common Lisp packages using
8639 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
8640 definition facility for Common Lisp programs and libraries.
8642 The @code{asdf-build-system/source} system installs the packages in
8643 source form, and can be loaded using any common lisp implementation, via
8644 ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
8645 systems in the format which a particular implementation understands.
8646 These build systems can also be used to produce executable programs, or
8647 lisp images which contain a set of packages pre-loaded.
8649 The build system uses naming conventions. For binary packages, the
8650 package name should be prefixed with the lisp implementation, such as
8651 @code{sbcl-} for @code{asdf-build-system/sbcl}.
8653 Additionally, the corresponding source package should be labeled using
8654 the same convention as python packages (see @ref{Python Modules}), using
8655 the @code{cl-} prefix.
8657 In order to create executable programs and images, the build-side
8658 procedures @code{build-program} and @code{build-image} can be used.
8659 They should be called in a build phase after the
8660 @code{create-asdf-configuration} phase, so that the system which was
8661 just built can be used within the resulting image. @code{build-program}
8662 requires a list of Common Lisp expressions to be passed as the
8663 @code{#:entry-program} argument.
8665 By default, all the @file{.asd} files present in the sources are read to
8666 find system definitions. The @code{#:asd-files} parameter can be used
8667 to specify the list of @file{.asd} files to read. Furthermore, if the
8668 package defines a system for its tests in a separate file, it will be
8669 loaded before the tests are run if it is specified by the
8670 @code{#:test-asd-file} parameter. If it is not set, the files
8671 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
8672 and @code{test.asd} will be tried if they exist.
8674 If for some reason the package must be named in a different way than the
8675 naming conventions suggest, or if several systems must be compiled, the
8676 @code{#:asd-systems} parameter can be used to specify the list of system
8681 @defvr {Scheme Variable} cargo-build-system
8682 @cindex Rust programming language
8683 @cindex Cargo (Rust build system)
8684 This variable is exported by @code{(guix build-system cargo)}. It
8685 supports builds of packages using Cargo, the build tool of the
8686 @uref{https://www.rust-lang.org, Rust programming language}.
8688 It adds @code{rustc} and @code{cargo} to the set of inputs.
8689 A different Rust package can be specified with the @code{#:rust} parameter.
8691 Regular cargo dependencies should be added to the package definition similarly
8692 to other packages; those needed only at build time to native-inputs, others to
8693 inputs. If you need to add source-only crates then you should add them to via
8694 the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
8695 spec can be a package or a source definition. Note that the spec must
8696 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
8697 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
8698 should be added to the package definition via the
8699 @code{#:cargo-development-inputs} parameter.
8701 In its @code{configure} phase, this build system will make any source inputs
8702 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
8703 parameters available to cargo. It will also remove an included
8704 @code{Cargo.lock} file to be recreated by @code{cargo} during the
8705 @code{build} phase. The @code{package} phase will run @code{cargo package}
8706 to create a source crate for future use. The @code{install} phase installs
8707 the binaries defined by the crate. Unless @code{install-source? #f} is
8708 defined it will also install a source crate repository of itself and unpacked
8709 sources, to ease in future hacking on rust packages.
8712 @defvr {Scheme Variable} chicken-build-system
8713 This variable is exported by @code{(guix build-system chicken)}. It
8714 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
8715 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
8716 gets compiled by a C compiler, in this case GCC.
8718 This build system adds @code{chicken} to the package inputs, as well as
8719 the packages of @code{gnu-build-system}.
8721 The build system can't (yet) deduce the egg's name automatically, so just like
8722 with @code{go-build-system} and its @code{#:import-path}, you should define
8723 @code{#:egg-name} in the package's @code{arguments} field.
8725 For example, if you are packaging the @code{srfi-1} egg:
8728 (arguments '(#:egg-name "srfi-1"))
8731 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
8732 because CHICKEN doesn't embed absolute references in compiled eggs.
8733 Test dependencies should go to @code{native-inputs}, as usual.
8736 @defvr {Scheme Variable} copy-build-system
8737 This variable is exported by @code{(guix build-system copy)}. It
8738 supports builds of simple packages that don't require much compiling,
8739 mostly just moving files around.
8741 It adds much of the @code{gnu-build-system} packages to the set of
8742 inputs. Because of this, the @code{copy-build-system} does not require
8743 all the boilerplate code often needed for the
8744 @code{trivial-build-system}.
8746 To further simplify the file installation process, an
8747 @code{#:install-plan} argument is exposed to let the packager specify
8748 which files go where. The install plan is a list of @code{(@var{source}
8749 @var{target} [@var{filters}])}. @var{filters} are optional.
8752 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
8754 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
8755 @item Otherwise install @var{source} as @var{target}.
8758 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
8759 the trailing slash of @var{target} is implied with the same meaning
8762 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
8763 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
8764 @code{#:exclude-regexp}, only select files are installed depending on
8765 the filters. Each filters is specified by a list of strings.
8767 @item With @code{#:include}, install all the files which the path suffix matches
8768 at least one of the elements in the given list.
8769 @item With @code{#:include-regexp}, install all the files which the
8770 subpaths match at least one of the regular expressions in the given
8772 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
8773 are the complement of their inclusion counterpart. Without @code{#:include} flags,
8774 install all files but those matching the exclusion filters.
8775 If both inclusions and exclusions are specified, the exclusions are done
8776 on top of the inclusions.
8779 In all cases, the paths relative to @var{source} are preserved within
8786 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
8787 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
8788 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
8789 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
8790 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
8791 @file{share/my-app/sub/file}.
8792 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
8793 @file{share/my-app/file}.
8798 @cindex Clojure (programming language)
8799 @cindex simple Clojure build system
8800 @defvr {Scheme Variable} clojure-build-system
8801 This variable is exported by @code{(guix build-system clojure)}. It implements
8802 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
8803 using plain old @code{compile} in Clojure. Cross-compilation is not supported
8806 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
8807 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
8808 @code{#:zip} parameters, respectively.
8810 A list of source directories, test directories and jar names can be specified
8811 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
8812 parameters, respectively. Compile directory and main class can be specified
8813 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
8814 Other parameters are documented below.
8816 This build system is an extension of @code{ant-build-system}, but with the
8817 following phases changed:
8822 This phase calls @code{compile} in Clojure to compile source files and runs
8823 @command{jar} to create jars from both source files and compiled files
8824 according to the include list and exclude list specified in
8825 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
8826 has priority over the include list. These lists consist of symbols
8827 representing Clojure libraries or the special keyword @code{#:all} representing
8828 all Clojure libraries found under the source directories. The parameter
8829 @code{#:omit-source?} decides if source should be included into the jars.
8832 This phase runs tests according to the include list and exclude list specified
8833 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
8834 meanings are analogous to that of @code{#:aot-include} and
8835 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
8836 stands for all Clojure libraries found under the test directories. The
8837 parameter @code{#:tests?} decides if tests should be run.
8840 This phase installs all jars built previously.
8843 Apart from the above, this build system also contains an additional phase:
8848 This phase installs all top-level files with base name matching
8849 @code{%doc-regex}. A different regex can be specified with the
8850 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
8851 directories specified in @code{#:doc-dirs} are installed as well.
8855 @defvr {Scheme Variable} cmake-build-system
8856 This variable is exported by @code{(guix build-system cmake)}. It
8857 implements the build procedure for packages using the
8858 @url{https://www.cmake.org, CMake build tool}.
8860 It automatically adds the @code{cmake} package to the set of inputs.
8861 Which package is used can be specified with the @code{#:cmake}
8864 The @code{#:configure-flags} parameter is taken as a list of flags
8865 passed to the @command{cmake} command. The @code{#:build-type}
8866 parameter specifies in abstract terms the flags passed to the compiler;
8867 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
8868 debugging information''), which roughly means that code is compiled with
8869 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
8872 @defvr {Scheme Variable} dune-build-system
8873 This variable is exported by @code{(guix build-system dune)}. It
8874 supports builds of packages using @uref{https://dune.build/, Dune}, a build
8875 tool for the OCaml programming language. It is implemented as an extension
8876 of the @code{ocaml-build-system} which is described below. As such, the
8877 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
8880 It automatically adds the @code{dune} package to the set of inputs.
8881 Which package is used can be specified with the @code{#:dune}
8884 There is no @code{configure} phase because dune packages typically don't
8885 need to be configured. The @code{#:build-flags} parameter is taken as a
8886 list of flags passed to the @code{dune} command during the build.
8888 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
8889 command instead of the more recent @code{dune} command while building
8890 a package. Its default value is @code{#f}.
8892 The @code{#:package} parameter can be passed to specify a package name, which
8893 is useful when a package contains multiple packages and you want to build
8894 only one of them. This is equivalent to passing the @code{-p} argument to
8899 @defvr {Scheme variable} elm-build-system
8900 This variable is exported by @code{(guix build-system elm)}. It implements a
8901 build procedure for @url{https://elm-lang.org, Elm} packages similar to
8904 The build system adds an Elm compiler package to the set of inputs. The
8905 default compiler package (currently @code{elm-sans-reactor}) can be overridden
8906 using the @code{#:elm} argument. Additionally, Elm packages needed by the
8907 build system itself are added as implicit inputs if they are not already
8908 present: to suppress this behavior, use the
8909 @code{#:implicit-elm-package-inputs?} argument, which is primarily useful for
8912 The @code{"dependencies"} and @code{"test-dependencies"} in an Elm package's
8913 @file{elm.json} file correspond to @code{propagated-inputs} and @code{inputs},
8916 Elm requires a particular structure for package names: @pxref{Elm Packages}
8917 for more details, including utilities provided by @code{(guix build-system
8920 There are currently a few noteworthy limitations to @code{elm-build-system}:
8924 The build system is focused on @dfn{packages} in the Elm sense of the word:
8925 Elm @dfn{projects} which declare @code{@{ "type": "package" @}} in their
8926 @file{elm.json} files. Using @code{elm-build-system} to build Elm
8927 @dfn{applications} (which declare @code{@{ "type": "application" @}}) is
8928 possible, but requires ad-hoc modifications to the build phases. For
8929 examples, see the definitions of the @code{elm-todomvc} example application and
8930 the @code{elm} package itself (because the front-end for the
8931 @samp{elm reactor} command is an Elm application).
8934 Elm supports multiple versions of a package coexisting simultaneously under
8935 @env{ELM_HOME}, but this does not yet work well with @code{elm-build-system}.
8936 This limitation primarily affects Elm applications, because they specify
8937 exact versions for their dependencies, whereas Elm packages specify supported
8938 version ranges. As a workaround, the example applications mentioned above use
8939 the @code{patch-application-dependencies} procedure provided by
8940 @code{(guix build elm-build-system)} to rewrite their @file{elm.json} files to
8941 refer to the package versions actually present in the build environment.
8942 Alternatively, Guix package transformations (@pxref{Defining Package
8943 Variants}) could be used to rewrite an application's entire dependency graph.
8946 We are not yet able to run tests for Elm projects because neither
8947 @url{https://github.com/mpizenberg/elm-test-rs, @command{elm-test-rs}} nor the
8948 Node.js-based @url{https://github.com/rtfeldman/node-test-runner,
8949 @command{elm-test}} runner has been packaged for Guix yet.
8953 @defvr {Scheme Variable} go-build-system
8954 This variable is exported by @code{(guix build-system go)}. It
8955 implements a build procedure for Go packages using the standard
8956 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
8957 Go build mechanisms}.
8959 The user is expected to provide a value for the key @code{#:import-path}
8960 and, in some cases, @code{#:unpack-path}. The
8961 @url{https://golang.org/doc/code.html#ImportPaths, import path}
8962 corresponds to the file system path expected by the package's build
8963 scripts and any referring packages, and provides a unique way to
8964 refer to a Go package. It is typically based on a combination of the
8965 package source code's remote URI and file system hierarchy structure. In
8966 some cases, you will need to unpack the package's source code to a
8967 different directory structure than the one indicated by the import path,
8968 and @code{#:unpack-path} should be used in such cases.
8970 Packages that provide Go libraries should install their source code into
8971 the built output. The key @code{#:install-source?}, which defaults to
8972 @code{#t}, controls whether or not the source code is installed. It can
8973 be set to @code{#f} for packages that only provide executable files.
8975 Packages can be cross-built, and if a specific architecture or operating
8976 system is desired then the keywords @code{#:goarch} and @code{#:goos}
8977 can be used to force the package to be built for that architecture and
8978 operating system. The combinations known to Go can be found
8979 @url{"https://golang.org/doc/install/source#environment", in their
8983 @defvr {Scheme Variable} glib-or-gtk-build-system
8984 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
8985 is intended for use with packages making use of GLib or GTK+.
8987 This build system adds the following two phases to the ones defined by
8988 @code{gnu-build-system}:
8991 @item glib-or-gtk-wrap
8992 The phase @code{glib-or-gtk-wrap} ensures that programs in
8993 @file{bin/} are able to find GLib ``schemas'' and
8994 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
8995 modules}. This is achieved by wrapping the programs in launch scripts
8996 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
8997 environment variables.
8999 It is possible to exclude specific package outputs from that wrapping
9000 process by listing their names in the
9001 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
9002 when an output is known not to contain any GLib or GTK+ binaries, and
9003 where wrapping would gratuitously add a dependency of that output on
9006 @item glib-or-gtk-compile-schemas
9007 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
9008 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
9009 GSettings schemas} of GLib are compiled. Compilation is performed by the
9010 @command{glib-compile-schemas} program. It is provided by the package
9011 @code{glib:bin} which is automatically imported by the build system.
9012 The @code{glib} package providing @command{glib-compile-schemas} can be
9013 specified with the @code{#:glib} parameter.
9016 Both phases are executed after the @code{install} phase.
9019 @defvr {Scheme Variable} guile-build-system
9020 This build system is for Guile packages that consist exclusively of Scheme
9021 code and that are so lean that they don't even have a makefile, let alone a
9022 @file{configure} script. It compiles Scheme code using @command{guild
9023 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
9024 installs the @file{.scm} and @file{.go} files in the right place. It also
9025 installs documentation.
9027 This build system supports cross-compilation by using the
9028 @option{--target} option of @samp{guild compile}.
9030 Packages built with @code{guile-build-system} must provide a Guile package in
9031 their @code{native-inputs} field.
9034 @defvr {Scheme Variable} julia-build-system
9035 This variable is exported by @code{(guix build-system julia)}. It
9036 implements the build procedure used by @uref{https://julialang.org/,
9037 julia} packages, which essentially is similar to running @samp{julia -e
9038 'using Pkg; Pkg.add(package)'} in an environment where
9039 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
9040 Tests are run by calling @code{/test/runtests.jl}.
9042 The Julia package name and uuid is read from the file
9043 @file{Project.toml}. These values can be overridden by passing the
9044 argument @code{#:julia-package-name} (which must be correctly
9045 capitalized) or @code{#:julia-package-uuid}.
9047 Julia packages usually manage their binary dependencies via
9048 @code{JLLWrappers.jl}, a Julia package that creates a module (named
9049 after the wrapped library followed by @code{_jll.jl}.
9051 To add the binary path @code{_jll.jl} packages, you need to patch the
9052 files under @file{src/wrappers/}, replacing the call to the macro
9053 @code{JLLWrappers.@@generate_wrapper_header}, adding as a second
9054 argument containing the store path the binary.
9056 As an example, in the MbedTLS Julia package, we add a build phase
9057 (@pxref{Build Phases}) to insert the absolute file name of the wrapped
9061 (add-after 'unpack 'override-binary-path
9062 (lambda* (#:key inputs #:allow-other-keys)
9063 (for-each (lambda (wrapper)
9064 (substitute* wrapper
9065 (("generate_wrapper_header.*")
9067 "generate_wrapper_header(\"MbedTLS\", \""
9068 (assoc-ref inputs "mbedtls-apache") "\")\n"))))
9069 ;; There's a Julia file for each platform, override them all.
9070 (find-files "src/wrappers/" "\\.jl$"))))
9073 Some older packages that aren't using @file{Project.toml} yet, will
9074 require this file to be created, too. It is internally done if the
9075 arguments @code{#:julia-package-name} and @code{#:julia-package-uuid}
9079 @defvr {Scheme Variable} maven-build-system
9080 This variable is exported by @code{(guix build-system maven)}. It implements
9081 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
9082 is a dependency and lifecycle management tool for Java. A user of Maven
9083 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
9084 When Maven does not have one of the dependencies or plugins in its repository,
9085 it will download them and use them to build the package.
9087 The maven build system ensures that maven will not try to download any
9088 dependency by running in offline mode. Maven will fail if a dependency is
9089 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
9090 modified to specify the version of dependencies and plugins that match the
9091 versions available in the guix build environment. Dependencies and plugins
9092 must be installed in the fake maven repository at @file{lib/m2}, and are
9093 symlinked into a proper repository before maven is run. Maven is instructed
9094 to use that repository for the build and installs built artifacts there.
9095 Changed files are copied to the @file{lib/m2} directory of the package output.
9097 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
9098 or let the build system use the default @file{pom.xml} file in the sources.
9100 In case you need to specify a dependency's version manually, you can use the
9101 @code{#:local-packages} argument. It takes an association list where the key
9102 is the groupId of the package and its value is an association list where the
9103 key is the artifactId of the package and its value is the version you want to
9104 override in the @file{pom.xml}.
9106 Some packages use dependencies or plugins that are not useful at runtime nor
9107 at build time in Guix. You can alter the @file{pom.xml} file to remove them
9108 using the @code{#:exclude} argument. Its value is an association list where
9109 the key is the groupId of the plugin or dependency you want to remove, and
9110 the value is a list of artifactId you want to remove.
9112 You can override the default @code{jdk} and @code{maven} packages with the
9113 corresponding argument, @code{#:jdk} and @code{#:maven}.
9115 The @code{#:maven-plugins} argument is a list of maven plugins used during
9116 the build, with the same format as the @code{inputs} fields of the package
9117 declaration. Its default value is @code{(default-maven-plugins)} which is
9121 @defvr {Scheme Variable} minetest-mod-build-system
9122 This variable is exported by @code{(guix build-system minetest)}. It
9123 implements a build procedure for @uref{https://www.minetest.net, Minetest}
9124 mods, which consists of copying Lua code, images and other resources to
9125 the location Minetest searches for mods. The build system also minimises
9126 PNG images and verifies that Minetest can load the mod without errors.
9129 @defvr {Scheme Variable} minify-build-system
9130 This variable is exported by @code{(guix build-system minify)}. It
9131 implements a minification procedure for simple JavaScript packages.
9133 It adds @code{uglify-js} to the set of inputs and uses it to compress
9134 all JavaScript files in the @file{src} directory. A different minifier
9135 package can be specified with the @code{#:uglify-js} parameter, but it
9136 is expected that the package writes the minified code to the standard
9139 When the input JavaScript files are not all located in the @file{src}
9140 directory, the parameter @code{#:javascript-files} can be used to
9141 specify a list of file names to feed to the minifier.
9144 @defvr {Scheme Variable} ocaml-build-system
9145 This variable is exported by @code{(guix build-system ocaml)}. It implements
9146 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
9147 of choosing the correct set of commands to run for each package. OCaml
9148 packages can expect many different commands to be run. This build system will
9151 When the package has a @file{setup.ml} file present at the top-level, it will
9152 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
9153 @code{ocaml setup.ml -install}. The build system will assume that this file
9154 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
9155 care of setting the prefix and enabling tests if they are not disabled. You
9156 can pass configure and build flags with the @code{#:configure-flags} and
9157 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
9158 set of flags used to enable tests. The @code{#:use-make?} key can be used to
9159 bypass this system in the build and install phases.
9161 When the package has a @file{configure} file, it is assumed that it is a
9162 hand-made configure script that requires a different argument format than
9163 in the @code{gnu-build-system}. You can add more flags with the
9164 @code{#:configure-flags} key.
9166 When the package has a @file{Makefile} file (or @code{#:use-make?} is
9167 @code{#t}), it will be used and more flags can be passed to the build and
9168 install phases with the @code{#:make-flags} key.
9170 Finally, some packages do not have these files and use a somewhat standard
9171 location for its build system. In that case, the build system will run
9172 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
9173 providing the path to the required findlib module. Additional flags can
9174 be passed via the @code{#:build-flags} key. Install is taken care of by
9175 @command{opam-installer}. In this case, the @code{opam} package must
9176 be added to the @code{native-inputs} field of the package definition.
9178 Note that most OCaml packages assume they will be installed in the same
9179 directory as OCaml, which is not what we want in guix. In particular, they
9180 will install @file{.so} files in their module's directory, which is usually
9181 fine because it is in the OCaml compiler directory. In guix though, these
9182 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
9183 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
9184 @file{.so} libraries should be installed.
9187 @defvr {Scheme Variable} python-build-system
9188 This variable is exported by @code{(guix build-system python)}. It
9189 implements the more or less standard build procedure used by Python
9190 packages, which consists in running @code{python setup.py build} and
9191 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
9193 For packages that install stand-alone Python programs under @code{bin/},
9194 it takes care of wrapping these programs so that their
9195 @env{GUIX_PYTHONPATH} environment variable points to all the Python
9196 libraries they depend on.
9198 Which Python package is used to perform the build can be specified with
9199 the @code{#:python} parameter. This is a useful way to force a package
9200 to be built for a specific version of the Python interpreter, which
9201 might be necessary if the package is only compatible with a single
9202 interpreter version.
9204 By default guix calls @code{setup.py} under control of
9205 @code{setuptools}, much like @command{pip} does. Some packages are not
9206 compatible with setuptools (and pip), thus you can disable this by
9207 setting the @code{#:use-setuptools?} parameter to @code{#f}.
9209 If a @code{"python"} output is available, the package is installed into it
9210 instead of the default @code{"out"} output. This is useful for packages that
9211 include a Python package as only a part of the software, and thus want to
9212 combine the phases of @code{python-build-system} with another build system.
9213 Python bindings are a common usecase.
9217 @defvr {Scheme Variable} perl-build-system
9218 This variable is exported by @code{(guix build-system perl)}. It
9219 implements the standard build procedure for Perl packages, which either
9220 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
9221 followed by @code{Build} and @code{Build install}; or in running
9222 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
9223 @code{make} and @code{make install}, depending on which of
9224 @code{Build.PL} or @code{Makefile.PL} is present in the package
9225 distribution. Preference is given to the former if both @code{Build.PL}
9226 and @code{Makefile.PL} exist in the package distribution. This
9227 preference can be reversed by specifying @code{#t} for the
9228 @code{#:make-maker?} parameter.
9230 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
9231 passes flags specified by the @code{#:make-maker-flags} or
9232 @code{#:module-build-flags} parameter, respectively.
9234 Which Perl package is used can be specified with @code{#:perl}.
9237 @defvr {Scheme Variable} renpy-build-system
9238 This variable is exported by @code{(guix build-system renpy)}. It implements
9239 the more or less standard build procedure used by Ren'py games, which consists
9240 of loading @code{#:game} once, thereby creating bytecode for it.
9242 It further creates a wrapper script in @code{bin/} and a desktop entry in
9243 @code{share/applications}, both of which can be used to launch the game.
9245 Which Ren'py package is used can be specified with @code{#:renpy}.
9246 Games can also be installed in outputs other than ``out'' by using
9250 @defvr {Scheme Variable} qt-build-system
9251 This variable is exported by @code{(guix build-system qt)}. It
9252 is intended for use with applications using Qt or KDE.
9254 This build system adds the following two phases to the ones defined by
9255 @code{cmake-build-system}:
9259 The phase @code{check-setup} prepares the environment for running
9260 the checks as commonly used by Qt test programs.
9261 For now this only sets some environment variables:
9262 @code{QT_QPA_PLATFORM=offscreen},
9263 @code{DBUS_FATAL_WARNINGS=0} and
9264 @code{CTEST_OUTPUT_ON_FAILURE=1}.
9266 This phase is added before the @code{check} phase.
9267 It's a separate phase to ease adjusting if necessary.
9270 The phase @code{qt-wrap}
9271 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
9272 and output. In case some path is found, all programs in the output's
9273 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
9274 are wrapped in scripts defining the necessary environment variables.
9276 It is possible to exclude specific package outputs from that wrapping process
9277 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
9278 This is useful when an output is known not to contain any Qt binaries, and
9279 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
9282 This phase is added after the @code{install} phase.
9286 @defvr {Scheme Variable} r-build-system
9287 This variable is exported by @code{(guix build-system r)}. It
9288 implements the build procedure used by @uref{https://r-project.org, R}
9289 packages, which essentially is little more than running @samp{R CMD
9290 INSTALL --library=/gnu/store/@dots{}} in an environment where
9291 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
9292 run after installation using the R function
9293 @code{tools::testInstalledPackage}.
9296 @defvr {Scheme Variable} rakudo-build-system
9297 This variable is exported by @code{(guix build-system rakudo)}. It
9298 implements the build procedure used by @uref{https://rakudo.org/,
9299 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
9300 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
9301 installs the binaries, library files and the resources, as well as wrap
9302 the files under the @code{bin/} directory. Tests can be skipped by
9303 passing @code{#f} to the @code{tests?} parameter.
9305 Which rakudo package is used can be specified with @code{rakudo}.
9306 Which perl6-tap-harness package used for the tests can be specified with
9307 @code{#:prove6} or removed by passing @code{#f} to the
9308 @code{with-prove6?} parameter.
9309 Which perl6-zef package used for tests and installing can be specified
9310 with @code{#:zef} or removed by passing @code{#f} to the
9311 @code{with-zef?} parameter.
9314 @defvr {Scheme Variable} rebar-build-system
9315 This variable is exported by @code{(guix build-system rebar)}. It
9316 implements a build procedure around @uref{https://rebar3.org,rebar3},
9317 a build system for programs written in the Erlang language.
9319 It adds both @code{rebar3} and the @code{erlang} to the set of inputs.
9320 Different packages can be specified with the @code{#:rebar} and
9321 @code{#:erlang} parameters, respectively.
9323 This build system is based on @code{gnu-build-system}, but with the
9324 following phases changed:
9329 This phase, after unpacking the source like the @code{gnu-build-system}
9330 does, checks for a file @code{contents.tar.gz} at the top-level of the
9331 source. If this file exists, it will be unpacked, too. This eases
9332 handling of package hosted at @uref{https://hex.pm/},
9333 the Erlang and Elixir package repository.
9337 There are no @code{bootstrap} and @code{configure} phase because erlang
9338 packages typically don’t need to be configured.
9341 This phase runs @code{rebar3 compile}
9342 with the flags listed in @code{#:rebar-flags}.
9345 Unless @code{#:tests? #f} is passed,
9346 this phase runs @code{rebar3 eunit},
9347 or some other target specified with @code{#:test-target},
9348 with the flags listed in @code{#:rebar-flags},
9351 This installs the files created in the @i{default} profile, or some
9352 other profile specified with @code{#:install-profile}.
9357 @defvr {Scheme Variable} texlive-build-system
9358 This variable is exported by @code{(guix build-system texlive)}. It is
9359 used to build TeX packages in batch mode with a specified engine. The
9360 build system sets the @env{TEXINPUTS} variable to find all TeX source
9361 files in the inputs.
9363 By default it runs @code{luatex} on all files ending on @code{ins}. A
9364 different engine and format can be specified with the
9365 @code{#:tex-format} argument. Different build targets can be specified
9366 with the @code{#:build-targets} argument, which expects a list of file
9367 names. The build system adds only @code{texlive-bin} and
9368 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
9369 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
9370 and @code{#:texlive-latex-base}, respectively.
9372 The @code{#:tex-directory} parameter tells the build system where to
9373 install the built files under the texmf tree.
9376 @defvr {Scheme Variable} ruby-build-system
9377 This variable is exported by @code{(guix build-system ruby)}. It
9378 implements the RubyGems build procedure used by Ruby packages, which
9379 involves running @code{gem build} followed by @code{gem install}.
9381 The @code{source} field of a package that uses this build system
9382 typically references a gem archive, since this is the format that Ruby
9383 developers use when releasing their software. The build system unpacks
9384 the gem archive, potentially patches the source, runs the test suite,
9385 repackages the gem, and installs it. Additionally, directories and
9386 tarballs may be referenced to allow building unreleased gems from Git or
9387 a traditional source release tarball.
9389 Which Ruby package is used can be specified with the @code{#:ruby}
9390 parameter. A list of additional flags to be passed to the @command{gem}
9391 command can be specified with the @code{#:gem-flags} parameter.
9394 @defvr {Scheme Variable} waf-build-system
9395 This variable is exported by @code{(guix build-system waf)}. It
9396 implements a build procedure around the @code{waf} script. The common
9397 phases---@code{configure}, @code{build}, and @code{install}---are
9398 implemented by passing their names as arguments to the @code{waf}
9401 The @code{waf} script is executed by the Python interpreter. Which
9402 Python package is used to run the script can be specified with the
9403 @code{#:python} parameter.
9406 @defvr {Scheme Variable} scons-build-system
9407 This variable is exported by @code{(guix build-system scons)}. It
9408 implements the build procedure used by the SCons software construction
9409 tool. This build system runs @code{scons} to build the package,
9410 @code{scons test} to run tests, and then @code{scons install} to install
9413 Additional flags to be passed to @code{scons} can be specified with the
9414 @code{#:scons-flags} parameter. The default build and install targets
9415 can be overridden with @code{#:build-targets} and
9416 @code{#:install-targets} respectively. The version of Python used to
9417 run SCons can be specified by selecting the appropriate SCons package
9418 with the @code{#:scons} parameter.
9421 @defvr {Scheme Variable} haskell-build-system
9422 This variable is exported by @code{(guix build-system haskell)}. It
9423 implements the Cabal build procedure used by Haskell packages, which
9424 involves running @code{runhaskell Setup.hs configure
9425 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
9426 Instead of installing the package by running @code{runhaskell Setup.hs
9427 install}, to avoid trying to register libraries in the read-only
9428 compiler store directory, the build system uses @code{runhaskell
9429 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
9430 addition, the build system generates the package documentation by
9431 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
9432 is passed. Optional Haddock parameters can be passed with the help of
9433 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
9434 not found, the build system looks for @code{Setup.lhs} instead.
9436 Which Haskell compiler is used can be specified with the @code{#:haskell}
9437 parameter which defaults to @code{ghc}.
9440 @defvr {Scheme Variable} dub-build-system
9441 This variable is exported by @code{(guix build-system dub)}. It
9442 implements the Dub build procedure used by D packages, which
9443 involves running @code{dub build} and @code{dub run}.
9444 Installation is done by copying the files manually.
9446 Which D compiler is used can be specified with the @code{#:ldc}
9447 parameter which defaults to @code{ldc}.
9450 @anchor{emacs-build-system}
9451 @defvr {Scheme Variable} emacs-build-system
9452 This variable is exported by @code{(guix build-system emacs)}. It
9453 implements an installation procedure similar to the packaging system
9454 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9456 It first creates the @code{@code{package}-autoloads.el} file, then it
9457 byte compiles all Emacs Lisp files. Differently from the Emacs
9458 packaging system, the Info documentation files are moved to the standard
9459 documentation directory and the @file{dir} file is deleted. The Elisp
9460 package files are installed directly under @file{share/emacs/site-lisp}.
9463 @defvr {Scheme Variable} font-build-system
9464 This variable is exported by @code{(guix build-system font)}. It
9465 implements an installation procedure for font packages where upstream
9466 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
9467 need to be copied into place. It copies font files to standard
9468 locations in the output directory.
9471 @defvr {Scheme Variable} meson-build-system
9472 This variable is exported by @code{(guix build-system meson)}. It
9473 implements the build procedure for packages that use
9474 @url{https://mesonbuild.com, Meson} as their build system.
9476 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
9477 of inputs, and they can be changed with the parameters @code{#:meson}
9478 and @code{#:ninja} if needed.
9480 This build system is an extension of @code{gnu-build-system}, but with the
9481 following phases changed to some specific for Meson:
9486 The phase runs @code{meson} with the flags specified in
9487 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
9488 @code{debugoptimized} unless something else is specified in
9489 @code{#:build-type}.
9492 The phase runs @code{ninja} to build the package in parallel by default, but
9493 this can be changed with @code{#:parallel-build?}.
9496 The phase runs @samp{meson test} with a base set of options that cannot
9497 be overridden. This base set of options can be extended via the
9498 @code{#:test-options} argument, for example to select or skip a specific
9502 The phase runs @code{ninja install} and can not be changed.
9505 Apart from that, the build system also adds the following phases:
9510 This phase ensures that all binaries can find the libraries they need.
9511 It searches for required libraries in subdirectories of the package
9512 being built, and adds those to @code{RUNPATH} where needed. It also
9513 removes references to libraries left over from the build phase by
9514 @code{meson}, such as test dependencies, that aren't actually required
9515 for the program to run.
9517 @item glib-or-gtk-wrap
9518 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9519 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9521 @item glib-or-gtk-compile-schemas
9522 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9523 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9527 @defvr {Scheme Variable} linux-module-build-system
9528 @code{linux-module-build-system} allows building Linux kernel modules.
9530 @cindex build phases
9531 This build system is an extension of @code{gnu-build-system}, but with the
9532 following phases changed:
9537 This phase configures the environment so that the Linux kernel's Makefile
9538 can be used to build the external kernel module.
9541 This phase uses the Linux kernel's Makefile in order to build the external
9545 This phase uses the Linux kernel's Makefile in order to install the external
9549 It is possible and useful to specify the Linux kernel to use for building
9550 the module (in the @code{arguments} form of a package using the
9551 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
9554 @defvr {Scheme Variable} node-build-system
9555 This variable is exported by @code{(guix build-system node)}. It
9556 implements the build procedure used by @uref{https://nodejs.org,
9557 Node.js}, which implements an approximation of the @code{npm install}
9558 command, followed by an @code{npm test} command.
9560 Which Node.js package is used to interpret the @code{npm} commands can
9561 be specified with the @code{#:node} parameter which defaults to
9565 Lastly, for packages that do not need anything as sophisticated, a
9566 ``trivial'' build system is provided. It is trivial in the sense that
9567 it provides basically no support: it does not pull any implicit inputs,
9568 and does not have a notion of build phases.
9570 @defvr {Scheme Variable} trivial-build-system
9571 This variable is exported by @code{(guix build-system trivial)}.
9573 This build system requires a @code{#:builder} argument. This argument
9574 must be a Scheme expression that builds the package output(s)---as
9575 with @code{build-expression->derivation} (@pxref{Derivations,
9576 @code{build-expression->derivation}}).
9579 @defvr {Scheme Variable} channel-build-system
9580 This variable is exported by @code{(guix build-system channel)}.
9582 This build system is meant primarily for internal use. A package using
9583 this build system must have a channel specification as its @code{source}
9584 field (@pxref{Channels}); alternatively, its source can be a directory
9585 name, in which case an additional @code{#:commit} argument must be
9586 supplied to specify the commit being built (a hexadecimal string).
9588 The resulting package is a Guix instance of the given channel, similar
9589 to how @command{guix time-machine} would build it.
9593 @section Build Phases
9595 @cindex build phases, for packages
9596 Almost all package build systems implement a notion @dfn{build phases}:
9597 a sequence of actions that the build system executes, when you build the
9598 package, leading to the installed byproducts in the store. A notable
9599 exception is the ``bare-bones'' @code{trivial-build-system}
9600 (@pxref{Build Systems}).
9602 As discussed in the previous section, those build systems provide a
9603 standard list of phases. For @code{gnu-build-system}, the main build
9604 phases are the following:
9608 Define search path environment variables for all the input packages,
9609 including @env{PATH} (@pxref{Search Paths}).
9612 Unpack the source tarball, and change the current directory to the
9613 extracted source tree. If the source is actually a directory, copy it
9614 to the build tree, and enter that directory.
9616 @item patch-source-shebangs
9617 Patch shebangs encountered in source files so they refer to the right
9618 store file names. For instance, this changes @code{#!/bin/sh} to
9619 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
9622 Run the @file{configure} script with a number of default options, such
9623 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
9624 by the @code{#:configure-flags} argument.
9627 Run @code{make} with the list of flags specified with
9628 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
9629 (the default), build with @code{make -j}.
9632 Run @code{make check}, or some other target specified with
9633 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
9634 @code{#:parallel-tests?} argument is true (the default), run @code{make
9638 Run @code{make install} with the flags listed in @code{#:make-flags}.
9640 @item patch-shebangs
9641 Patch shebangs on the installed executable files.
9644 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
9645 is false), copying them to the @code{debug} output when available
9646 (@pxref{Installing Debugging Files}).
9648 @cindex RUNPATH, validation
9649 @anchor{phase-validate-runpath}
9650 @item validate-runpath
9651 Validate the @code{RUNPATH} of ELF binaries, unless
9652 @code{#:validate-runpath?} is false (@pxref{Build Systems}).
9654 This validation step consists in making sure that all the shared
9655 libraries needed by an ELF binary, which are listed as @code{DT_NEEDED}
9656 entries in its @code{PT_DYNAMIC} segment, appear in the
9657 @code{DT_RUNPATH} entry of that binary. In other words, it ensures that
9658 running or using those binaries will not result in a ``file not found''
9659 error at run time. @xref{Options, @option{-rpath},, ld, The GNU
9660 Linker}, for more information on @code{RUNPATH}.
9664 Other build systems have similar phases, with some variations. For
9665 example, @code{cmake-build-system} has same-named phases but its
9666 @code{configure} phases runs @code{cmake} instead of @code{./configure}.
9667 Others, such as @code{python-build-system}, have a wholly different list
9668 of standard phases. All this code runs on the @dfn{build side}: it is
9669 evaluated when you actually build the package, in a dedicated build
9670 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
9672 Build phases are represented as association lists or ``alists''
9673 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
9674 each key is a symbol for the name of the phase and the associated value
9675 is a procedure that accepts an arbitrary number of arguments. By
9676 convention, those procedures receive information about the build in the
9677 form of @dfn{keyword parameters}, which they can use or ignore.
9679 @vindex %standard-phases
9680 For example, here is how @code{(guix build gnu-build-system)} defines
9681 @code{%standard-phases}, the variable holding its alist of build
9682 phases@footnote{We present a simplified view of those build phases, but
9683 do take a look at @code{(guix build gnu-build-system)} to see all the
9687 ;; The build phases of 'gnu-build-system'.
9689 (define* (unpack #:key source #:allow-other-keys)
9690 ;; Extract the source tarball.
9691 (invoke "tar" "xvf" source))
9693 (define* (configure #:key outputs #:allow-other-keys)
9694 ;; Run the 'configure' script. Install to output "out".
9695 (let ((out (assoc-ref outputs "out")))
9696 (invoke "./configure"
9697 (string-append "--prefix=" out))))
9699 (define* (build #:allow-other-keys)
9703 (define* (check #:key (test-target "check") (tests? #true)
9705 ;; Run the test suite.
9707 (invoke "make" test-target)
9708 (display "test suite not run\n")))
9710 (define* (install #:allow-other-keys)
9711 ;; Install files to the prefix 'configure' specified.
9712 (invoke "make" "install"))
9714 (define %standard-phases
9715 ;; The list of standard phases (quite a few are omitted
9716 ;; for brevity). Each element is a symbol/procedure pair.
9717 (list (cons 'unpack unpack)
9718 (cons 'configure configure)
9721 (cons 'install install)))
9724 This shows how @code{%standard-phases} is defined as a list of
9725 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
9726 Manual}). The first pair associates the @code{unpack} procedure with
9727 the @code{unpack} symbol---a name; the second pair defines the
9728 @code{configure} phase similarly, and so on. When building a package
9729 that uses @code{gnu-build-system} with its default list of phases, those
9730 phases are executed sequentially. You can see the name of each phase
9731 started and completed in the build log of packages that you build.
9733 Let's now look at the procedures themselves. Each one is defined with
9734 @code{define*}: @code{#:key} lists keyword parameters the procedure
9735 accepts, possibly with a default value, and @code{#:allow-other-keys}
9736 specifies that other keyword parameters are ignored (@pxref{Optional
9737 Arguments,,, guile, GNU Guile Reference Manual}).
9739 The @code{unpack} procedure honors the @code{source} parameter, which
9740 the build system uses to pass the file name of the source tarball (or
9741 version control checkout), and it ignores other parameters. The
9742 @code{configure} phase only cares about the @code{outputs} parameter, an
9743 alist mapping package output names to their store file name
9744 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
9745 for @code{out}, the default output, and passes it to
9746 @command{./configure} as the installation prefix, meaning that
9747 @command{make install} will eventually copy all the files in that
9748 directory (@pxref{Configuration, configuration and makefile
9749 conventions,, standards, GNU Coding Standards}). @code{build} and
9750 @code{install} ignore all their arguments. @code{check} honors the
9751 @code{test-target} argument, which specifies the name of the Makefile
9752 target to run tests; it prints a message and skips tests when
9753 @code{tests?} is false.
9755 @cindex build phases, customizing
9756 The list of phases used for a particular package can be changed with the
9757 @code{#:phases} parameter of the build system. Changing the set of
9758 build phases boils down to building a new alist of phases based on the
9759 @code{%standard-phases} alist described above. This can be done with
9760 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
9761 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
9762 more convenient to do so with @code{modify-phases} (@pxref{Build
9763 Utilities, @code{modify-phases}}).
9765 Here is an example of a package definition that removes the
9766 @code{configure} phase of @code{%standard-phases} and inserts a new
9767 phase before the @code{build} phase, called
9768 @code{set-prefix-in-makefile}:
9771 (define-public example
9774 ;; other fields omitted
9775 (build-system gnu-build-system)
9777 '(#:phases (modify-phases %standard-phases
9779 (add-before 'build 'set-prefix-in-makefile
9780 (lambda* (#:key outputs #:allow-other-keys)
9781 ;; Modify the makefile so that its
9782 ;; 'PREFIX' variable points to "out".
9783 (let ((out (assoc-ref outputs "out")))
9784 (substitute* "Makefile"
9786 (string-append "PREFIX = "
9790 The new phase that is inserted is written as an anonymous procedure,
9791 introduced with @code{lambda*}; it honors the @code{outputs} parameter
9792 we have seen before. @xref{Build Utilities}, for more about the helpers
9793 used by this phase, and for more examples of @code{modify-phases}.
9795 @cindex code staging
9796 @cindex staging, of code
9797 Keep in mind that build phases are code evaluated at the time the
9798 package is actually built. This explains why the whole
9799 @code{modify-phases} expression above is quoted (it comes after the
9800 @code{'} or apostrophe): it is @dfn{staged} for later execution.
9801 @xref{G-Expressions}, for an explanation of code staging and the
9802 @dfn{code strata} involved.
9804 @node Build Utilities
9805 @section Build Utilities
9807 As soon as you start writing non-trivial package definitions
9808 (@pxref{Defining Packages}) or other build actions
9809 (@pxref{G-Expressions}), you will likely start looking for helpers for
9810 ``shell-like'' actions---creating directories, copying and deleting
9811 files recursively, manipulating build phases, and so on. The
9812 @code{(guix build utils)} module provides such utility procedures.
9814 Most build systems load @code{(guix build utils)} (@pxref{Build
9815 Systems}). Thus, when writing custom build phases for your package
9816 definitions, you can usually assume those procedures are in scope.
9818 When writing G-expressions, you can import @code{(guix build utils)} on
9819 the ``build side'' using @code{with-imported-modules} and then put it in
9820 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
9821 guile, GNU Guile Reference Manual}):
9824 (with-imported-modules '((guix build utils)) ;import it
9825 (computed-file "empty-tree"
9828 (use-modules (guix build utils))
9830 ;; Happily use its 'mkdir-p' procedure.
9831 (mkdir-p (string-append #$output "/a/b/c")))))
9834 The remainder of this section is the reference for most of the utility
9835 procedures provided by @code{(guix build utils)}.
9837 @c TODO Document what's missing.
9839 @subsection Dealing with Store File Names
9841 This section documents procedures that deal with store file names.
9843 @deffn {Scheme Procedure} %store-directory
9844 Return the directory name of the store.
9847 @deffn {Scheme Procedure} store-file-name? @var{file}
9848 Return true if @var{file} is in the store.
9851 @deffn {Scheme Procedure} strip-store-file-name @var{file}
9852 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
9853 The result is typically a @code{"@var{package}-@var{version}"} string.
9856 @deffn {Scheme Procedure} package-name->name+version @var{name}
9857 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
9858 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
9859 unavailable, @var{name} and @code{#f} are returned. The first hyphen
9860 followed by a digit is considered to introduce the version part.
9863 @subsection File Types
9865 The procedures below deal with files and file types.
9867 @deffn {Scheme Procedure} directory-exists? @var{dir}
9868 Return @code{#t} if @var{dir} exists and is a directory.
9871 @deffn {Scheme Procedure} executable-file? @var{file}
9872 Return @code{#t} if @var{file} exists and is executable.
9875 @deffn {Scheme Procedure} symbolic-link? @var{file}
9876 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
9879 @deffn {Scheme Procedure} elf-file? @var{file}
9880 @deffnx {Scheme Procedure} ar-file? @var{file}
9881 @deffnx {Scheme Procedure} gzip-file? @var{file}
9882 Return @code{#t} if @var{file} is, respectively, an ELF file, an
9883 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
9886 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
9887 If @var{file} is a gzip file, reset its embedded timestamp (as with
9888 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
9889 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
9892 @subsection File Manipulation
9894 The following procedures and macros help create, modify, and delete
9895 files. They provide functionality comparable to common shell utilities
9896 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
9897 @command{sed}. They complement Guile's extensive, but low-level, file
9898 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
9900 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
9901 Run @var{body} with @var{directory} as the process's current directory.
9903 Essentially, this macro changes the current directory to @var{directory}
9904 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
9905 guile, GNU Guile Reference Manual}). It changes back to the initial
9906 directory when the dynamic extent of @var{body} is left, be it @i{via}
9907 normal procedure return or @i{via} a non-local exit such as an
9911 @deffn {Scheme Procedure} mkdir-p @var{dir}
9912 Create directory @var{dir} and all its ancestors.
9915 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
9916 Create @var{directory} if it does not exist and copy @var{file} in there
9917 under the same name.
9920 @deffn {Scheme Procedure} make-file-writable @var{file}
9921 Make @var{file} writable for its owner.
9924 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
9925 [#:log (current-output-port)] [#:follow-symlinks? #f] @
9926 [#:copy-file copy-file] [#:keep-mtime? #f] [#:keep-permissions? #t]
9927 Copy @var{source} directory to @var{destination}. Follow symlinks if
9928 @var{follow-symlinks?} is true; otherwise, just preserve them. Call
9929 @var{copy-file} to copy regular files. When @var{keep-mtime?} is true,
9930 keep the modification time of the files in @var{source} on those of
9931 @var{destination}. When @var{keep-permissions?} is true, preserve file
9932 permissions. Write verbose output to the @var{log} port.
9935 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
9936 [#:follow-mounts? #f]
9937 Delete @var{dir} recursively, like @command{rm -rf}, without following
9938 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
9939 is true. Report but ignore errors.
9942 @deffn {Scheme Syntax} substitute* @var{file} @
9943 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
9944 Substitute @var{regexp} in @var{file} by the string returned by
9945 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
9946 the corresponding positional regexp sub-expression. For example:
9952 (("foo([a-z]+)bar(.*)$" all letters end)
9953 (string-append "baz" letters end)))
9956 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
9957 by @code{good morning}. Anytime a line of @var{file} matches the second
9958 regexp, @code{all} is bound to the complete match, @code{letters} is bound
9959 to the first sub-expression, and @code{end} is bound to the last one.
9961 When one of the @var{match-var} is @code{_}, no variable is bound to the
9962 corresponding match substring.
9964 Alternatively, @var{file} may be a list of file names, in which case
9965 they are all subject to the substitutions.
9967 Be careful about using @code{$} to match the end of a line; by itself it
9968 won't match the terminating newline of a line.
9971 @subsection File Search
9973 @cindex file, searching
9974 This section documents procedures to search and filter files.
9976 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
9977 Return a predicate that returns true when passed a file name whose base
9978 name matches @var{regexp}.
9981 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
9982 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
9983 Return the lexicographically sorted list of files under @var{dir} for
9984 which @var{pred} returns true. @var{pred} is passed two arguments: the
9985 absolute file name, and its stat buffer; the default predicate always
9986 returns true. @var{pred} can also be a regular expression, in which
9987 case it is equivalent to @code{(file-name-predicate @var{pred})}.
9988 @var{stat} is used to obtain file information; using @code{lstat} means
9989 that symlinks are not followed. If @var{directories?} is true, then
9990 directories will also be included. If @var{fail-on-error?} is true,
9991 raise an exception upon error.
9994 Here are a few examples where we assume that the current directory is
9995 the root of the Guix source tree:
9998 ;; List all the regular files in the current directory.
10000 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
10002 ;; List all the .scm files under gnu/services.
10003 (find-files "gnu/services" "\\.scm$")
10004 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
10006 ;; List ar files in the current directory.
10007 (find-files "." (lambda (file stat) (ar-file? file)))
10008 @result{} ("./libformat.a" "./libstore.a" @dots{})
10011 @deffn {Scheme Procedure} which @var{program}
10012 Return the complete file name for @var{program} as found in
10013 @code{$PATH}, or @code{#f} if @var{program} could not be found.
10016 @deffn {Scheme Procedure} search-input-file @var{inputs} @var{name}
10017 @deffnx {Scheme Procedure} search-input-directory @var{inputs} @var{name}
10018 Return the complete file name for @var{name} as found in @var{inputs};
10019 @code{search-input-file} searches for a regular file and
10020 @code{search-input-directory} searches for a directory. If @var{name}
10021 could not be found, an exception is raised.
10023 Here, @var{inputs} must be an association list like @code{inputs} and
10024 @code{native-inputs} as available to build phases (@pxref{Build
10028 Here is a (simplified) example of how @code{search-input-file} is used
10029 in a build phase of the @code{wireguard-tools} package:
10032 (add-after 'install 'wrap-wg-quick
10033 (lambda* (#:key inputs outputs #:allow-other-keys)
10034 (let ((coreutils (string-append (assoc-ref inputs "coreutils")
10036 (wrap-program (search-input-file outputs "bin/wg-quick")
10037 #:sh (search-input-file inputs "bin/bash")
10038 `("PATH" ":" prefix ,(list coreutils))))))
10041 @subsection Program Invocation
10043 @cindex program invocation, from Scheme
10044 @cindex invoking programs, from Scheme
10045 You'll find handy procedures to spawn processes in this module,
10046 essentially convenient wrappers around Guile's @code{system*}
10047 (@pxref{Processes, @code{system*},, guile, GNU Guile Reference Manual}).
10049 @deffn {Scheme Procedure} invoke @var{program} @var{args}@dots{}
10050 Invoke @var{program} with the given @var{args}. Raise an
10051 @code{&invoke-error} exception if the exit code is non-zero; otherwise
10054 The advantage compared to @code{system*} is that you do not need to
10055 check the return value. This reduces boilerplate in shell-script-like
10056 snippets for instance in package build phases.
10059 @deffn {Scheme Procedure} invoke-error? @var{c}
10060 Return true if @var{c} is an @code{&invoke-error} condition.
10063 @deffn {Scheme Procedure} invoke-error-program @var{c}
10064 @deffnx {Scheme Procedure} invoke-error-arguments @var{c}
10065 @deffnx {Scheme Procedure} invoke-error-exit-status @var{c}
10066 @deffnx {Scheme Procedure} invoke-error-term-signal @var{c}
10067 @deffnx {Scheme Procedure} invoke-error-stop-signal @var{c}
10068 Access specific fields of @var{c}, an @code{&invoke-error} condition.
10071 @deffn {Scheme Procedure} report-invoke-error @var{c} [@var{port}]
10072 Report to @var{port} (by default the current error port) about @var{c},
10073 an @code{&invoke-error} condition, in a human-friendly way.
10075 Typical usage would look like this:
10078 (use-modules (srfi srfi-34) ;for 'guard'
10079 (guix build utils))
10081 (guard (c ((invoke-error? c)
10082 (report-invoke-error c)))
10083 (invoke "date" "--imaginary-option"))
10085 @print{} command "date" "--imaginary-option" failed with status 1
10089 @deffn {Scheme Procedure} invoke/quiet @var{program} @var{args}@dots{}
10090 Invoke @var{program} with @var{args} and capture @var{program}'s
10091 standard output and standard error. If @var{program} succeeds, print
10092 nothing and return the unspecified value; otherwise, raise a
10093 @code{&message} error condition that includes the status code and the
10094 output of @var{program}.
10099 (use-modules (srfi srfi-34) ;for 'guard'
10100 (srfi srfi-35) ;for 'message-condition?'
10101 (guix build utils))
10103 (guard (c ((message-condition? c)
10104 (display (condition-message c))))
10105 (invoke/quiet "date") ;all is fine
10106 (invoke/quiet "date" "--imaginary-option"))
10108 @print{} 'date --imaginary-option' exited with status 1; output follows:
10110 date: unrecognized option '--imaginary-option'
10111 Try 'date --help' for more information.
10115 @subsection Build Phases
10117 @cindex build phases
10118 The @code{(guix build utils)} also contains tools to manipulate build
10119 phases as used by build systems (@pxref{Build Systems}). Build phases
10120 are represented as association lists or ``alists'' (@pxref{Association
10121 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
10122 naming the phase and the associated value is a procedure (@pxref{Build
10125 Guile core and the @code{(srfi srfi-1)} module both provide tools to
10126 manipulate alists. The @code{(guix build utils)} module complements
10127 those with tools written with build phases in mind.
10129 @cindex build phases, modifying
10130 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
10131 Modify @var{phases} sequentially as per each @var{clause}, which may
10132 have one of the following forms:
10135 (delete @var{old-phase-name})
10136 (replace @var{old-phase-name} @var{new-phase})
10137 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10138 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10141 Where every @var{phase-name} above is an expression evaluating to a
10142 symbol, and @var{new-phase} an expression evaluating to a procedure.
10145 The example below is taken from the definition of the @code{grep}
10146 package. It adds a phase to run after the @code{install} phase, called
10147 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
10148 is for anonymous procedures) that takes a @code{#:outputs} keyword
10149 argument and ignores extra keyword arguments (@pxref{Optional
10150 Arguments,,, guile, GNU Guile Reference Manual}, for more on
10151 @code{lambda*} and optional and keyword arguments.) The phase uses
10152 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
10153 scripts so that they refer to @code{grep} by its absolute file name:
10156 (modify-phases %standard-phases
10157 (add-after 'install 'fix-egrep-and-fgrep
10158 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
10159 ;; absolute file name instead of searching for it in $PATH.
10160 (lambda* (#:key outputs #:allow-other-keys)
10161 (let* ((out (assoc-ref outputs "out"))
10162 (bin (string-append out "/bin")))
10163 (substitute* (list (string-append bin "/egrep")
10164 (string-append bin "/fgrep"))
10166 (string-append "exec " bin "/grep")))))))
10169 In the example below, phases are modified in two ways: the standard
10170 @code{configure} phase is deleted, presumably because the package does
10171 not have a @file{configure} script or anything similar, and the default
10172 @code{install} phase is replaced by one that manually copies the
10173 executable files to be installed:
10176 (modify-phases %standard-phases
10177 (delete 'configure) ;no 'configure' script
10179 (lambda* (#:key outputs #:allow-other-keys)
10180 ;; The package's Makefile doesn't provide an "install"
10181 ;; rule so do it by ourselves.
10182 (let ((bin (string-append (assoc-ref outputs "out")
10184 (install-file "footswitch" bin)
10185 (install-file "scythe" bin)))))
10188 @c TODO: Add more examples.
10190 @subsection Wrappers
10192 @cindex program wrappers
10193 @cindex wrapping programs
10194 It is not unusual for a command to require certain environment variables
10195 to be set for proper functioning, typically search paths (@pxref{Search
10196 Paths}). Failing to do that, the command might fail to find files or
10197 other commands it relies on, or it might pick the ``wrong''
10198 ones---depending on the environment in which it runs. Examples include:
10202 a shell script that assumes all the commands it uses are in @env{PATH};
10205 a Guile program that assumes all its modules are in @env{GUILE_LOAD_PATH}
10206 and @env{GUILE_LOAD_COMPILED_PATH};
10209 a Qt application that expects to find certain plugins in
10210 @env{QT_PLUGIN_PATH}.
10213 For a package writer, the goal is to make sure commands always work the
10214 same rather than depend on some external settings. One way to achieve
10215 that is to @dfn{wrap} commands in a thin script that sets those
10216 environment variables, thereby ensuring that those run-time dependencies
10217 are always found. The wrapper would be used to set @env{PATH},
10218 @env{GUILE_LOAD_PATH}, or @env{QT_PLUGIN_PATH} in the examples above.
10220 To ease that task, the @code{(guix build utils)} module provides a
10221 couple of helpers to wrap commands.
10223 @deffn {Scheme Procedure} wrap-program @var{program} @
10224 [#:sh @var{sh}] [#:rest @var{variables}]
10225 Make a wrapper for @var{program}. @var{variables} should look like this:
10228 '(@var{variable} @var{delimiter} @var{position} @var{list-of-directories})
10231 where @var{delimiter} is optional. @code{:} will be used if
10232 @var{delimiter} is not given.
10234 For example, this call:
10237 (wrap-program "foo"
10238 '("PATH" ":" = ("/gnu/.../bar/bin"))
10239 '("CERT_PATH" suffix ("/gnu/.../baz/certs"
10243 will copy @file{foo} to @file{.foo-real} and create the file @file{foo}
10244 with the following contents:
10247 #!location/of/bin/bash
10248 export PATH="/gnu/.../bar/bin"
10249 export CERT_PATH="$CERT_PATH$@{CERT_PATH:+:@}/gnu/.../baz/certs:/qux/certs"
10250 exec -a $0 location/of/.foo-real "$@@"
10253 If @var{program} has previously been wrapped by @code{wrap-program}, the
10254 wrapper is extended with definitions for @var{variables}. If it is not,
10255 @var{sh} will be used as the interpreter.
10258 @deffn {Scheme Procedure} wrap-script @var{program} @
10259 [#:guile @var{guile}] [#:rest @var{variables}]
10260 Wrap the script @var{program} such that @var{variables} are set first.
10261 The format of @var{variables} is the same as in the @code{wrap-program}
10262 procedure. This procedure differs from @code{wrap-program} in that it
10263 does not create a separate shell script. Instead, @var{program} is
10264 modified directly by prepending a Guile script, which is interpreted as
10265 a comment in the script's language.
10267 Special encoding comments as supported by Python are recreated on the
10270 Note that this procedure can only be used once per file as Guile scripts are
10275 @section Search Paths
10277 @cindex search path
10278 Many programs and libraries look for input data in a @dfn{search path},
10279 a list of directories: shells like Bash look for executables in the
10280 command search path, a C compiler looks for @file{.h} files in its
10281 header search path, the Python interpreter looks for @file{.py}
10282 files in its search path, the spell checker has a search path for
10283 dictionaries, and so on.
10285 Search paths can usually be defined or overridden @i{via} environment
10286 variables (@pxref{Environment Variables,,, libc, The GNU C Library
10287 Reference Manual}). For example, the search paths mentioned above can
10288 be changed by defining the @env{PATH}, @env{C_INCLUDE_PATH},
10289 @env{PYTHONPATH} (or @env{GUIX_PYTHONPATH}), and @env{DICPATH}
10290 environment variables---you know, all these something-PATH variables
10291 that you need to get right or things ``won't be found''.
10293 You may have noticed from the command line that Guix ``knows'' which
10294 search path environment variables should be defined, and how. When you
10295 install packages in your default profile, the file
10296 @file{~/.guix-profile/etc/profile} is created, which you can ``source''
10297 from the shell to set those variables. Likewise, if you ask
10298 @command{guix shell} to create an environment containing Python and
10299 NumPy, a Python library, and if you pass it the @option{--search-paths}
10300 option, it will tell you about @env{PATH} and @env{GUIX_PYTHONPATH}
10301 (@pxref{Invoking guix shell}):
10304 $ guix shell python python-numpy --pure --search-paths
10305 export PATH="/gnu/store/@dots{}-profile/bin"
10306 export GUIX_PYTHONPATH="/gnu/store/@dots{}-profile/lib/python3.9/site-packages"
10309 When you omit @option{--search-paths}, it defines these environment
10310 variables right away, such that Python can readily find NumPy:
10313 $ guix shell python python-numpy -- python3
10314 Python 3.9.6 (default, Jan 1 1970, 00:00:01)
10315 [GCC 10.3.0] on linux
10316 Type "help", "copyright", "credits" or "license" for more information.
10318 >>> numpy.version.version
10322 For this to work, the definition of the @code{python} package
10323 @emph{declares} the search path it cares about and its associated
10324 environment variable, @env{GUIX_PYTHONPATH}. It looks like this:
10330 ;; some fields omitted...
10331 (native-search-paths
10332 (list (search-path-specification
10333 (variable "GUIX_PYTHONPATH")
10334 (files (list "lib/python/3.9/site-packages"))))))
10337 What this @code{native-search-paths} field says is that, when the
10338 @code{python} package is used, the @env{GUIX_PYTHONPATH} environment
10339 variable must be defined to include all the
10340 @file{lib/python/3.9/site-packages} sub-directories encountered in its
10341 environment. (The @code{native-} bit means that, if we are in a
10342 cross-compilation environment, only native inputs may be added to the
10343 search path; @pxref{package Reference, @code{search-paths}}.)
10344 In the NumPy example above, the profile where
10345 @code{python} appears contains exactly one such sub-directory, and
10346 @env{GUIX_PYTHONPATH} is set to that. When there are several
10347 @file{lib/python/3.9/site-packages}---this is the case in package build
10348 environments---they are all added to @env{GUIX_PYTHONPATH}, separated by
10352 Notice that @env{GUIX_PYTHONPATH} is specified as part of the definition
10353 of the @code{python} package, and @emph{not} as part of that of
10354 @code{python-numpy}. This is because this environment variable
10355 ``belongs'' to Python, not NumPy: Python actually reads the value of
10356 that variable and honors it.
10358 Corollary: if you create a profile that does not contain @code{python},
10359 @code{GUIX_PYTHONPATH} will @emph{not} be defined, even if it contains
10360 packages that provide @file{.py} files:
10363 $ guix shell python-numpy --search-paths --pure
10364 export PATH="/gnu/store/@dots{}-profile/bin"
10367 This makes a lot of sense if we look at this profile in isolation: no
10368 software in this profile would read @env{GUIX_PYTHONPATH}.
10371 Of course, there are many variations on that theme: some packages honor
10372 more than one search path, some use separators other than colon, some
10373 accumulate several directories in their search path, and so on. A more
10374 complex example is the search path of libxml2: the value of the
10375 @env{XML_CATALOG_FILES} environment variable is space-separated, it must
10376 contain a list of @file{catalog.xml} files (not directories), which are
10377 to be found in @file{xml} sub-directories---nothing less. The search
10378 path specification looks like this:
10383 ;; some fields omitted
10384 (native-search-paths
10385 (list (search-path-specification
10386 (variable "XML_CATALOG_FILES")
10389 (file-pattern "^catalog\\.xml$")
10390 (file-type 'regular)))))
10393 Worry not, search path specifications are usually not this tricky.
10395 The @code{(guix search-paths)} module defines the data type of search
10396 path specifications and a number of helper procedures. Below is the
10397 reference of search path specifications.
10399 @deftp {Data Type} search-path-specification
10400 The data type for search path specifications.
10403 @item @code{variable}
10404 The name of the environment variable for this search path (a string).
10407 The list of sub-directories (strings) that should be added to the search
10410 @item @code{separator} (default: @code{":"})
10411 The string used to separate search path components.
10413 As a special case, a @code{separator} value of @code{#f} specifies a
10414 ``single-component search path''---in other words, a search path that
10415 cannot contain more than one element. This is useful in some cases,
10416 such as the @code{SSL_CERT_DIR} variable (honored by OpenSSL, cURL, and
10417 a few other packages) or the @code{ASPELL_DICT_DIR} variable (honored by
10418 the GNU Aspell spell checker), both of which must point to a single
10421 @item @code{file-type} (default: @code{'directory})
10422 The type of file being matched---@code{'directory} or @code{'regular},
10423 though it can be any symbol returned by @code{stat:type} (@pxref{File
10424 System, @code{stat},, guile, GNU Guile Reference Manual}).
10426 In the libxml2 example above, we would match regular files; in the
10427 Python example, we would match directories.
10429 @item @code{file-pattern} (default: @code{#f})
10430 This must be either @code{#f} or a regular expression specifying
10431 files to be matched @emph{within} the sub-directories specified by the
10432 @code{files} field.
10434 Again, the libxml2 example shows a situation where this is needed.
10438 Some search paths are not tied by a single package but to many packages.
10439 To reduce duplications, some of them are pre-defined in @code{(guix
10442 @defvr {Scheme Variable} $SSL_CERT_DIR
10443 @defvrx {Scheme Variable} $SSL_CERT_FILE
10444 These two search paths indicate where X.509 certificates can be found
10445 (@pxref{X.509 Certificates}).
10448 These pre-defined search paths can be used as in the following example:
10453 ;; some fields omitted ...
10454 (native-search-paths (list $SSL_CERT_DIR $SSL_CERT_FILE)))
10457 How do you turn search path specifications on one hand and a bunch of
10458 directories on the other hand in a set of environment variable
10459 definitions? That's the job of @code{evaluate-search-paths}.
10461 @deffn {Scheme Procedure} evaluate-search-paths @var{search-paths} @
10462 @var{directories} [@var{getenv}]
10463 Evaluate @var{search-paths}, a list of search-path specifications, for
10464 @var{directories}, a list of directory names, and return a list of
10465 specification/value pairs. Use @var{getenv} to determine the current
10466 settings and report only settings not already effective.
10469 The @code{(guix profiles)} provides a higher-level helper procedure,
10470 @code{load-profile}, that sets the environment variables of a profile.
10476 @cindex store items
10477 @cindex store paths
10479 Conceptually, the @dfn{store} is the place where derivations that have
10480 been built successfully are stored---by default, @file{/gnu/store}.
10481 Sub-directories in the store are referred to as @dfn{store items} or
10482 sometimes @dfn{store paths}. The store has an associated database that
10483 contains information such as the store paths referred to by each store
10484 path, and the list of @emph{valid} store items---results of successful
10485 builds. This database resides in @file{@var{localstatedir}/guix/db},
10486 where @var{localstatedir} is the state directory specified @i{via}
10487 @option{--localstatedir} at configure time, usually @file{/var}.
10489 The store is @emph{always} accessed by the daemon on behalf of its clients
10490 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
10491 connect to the daemon over a Unix-domain socket, send requests to it,
10492 and read the result---these are remote procedure calls, or RPCs.
10495 Users must @emph{never} modify files under @file{/gnu/store} directly.
10496 This would lead to inconsistencies and break the immutability
10497 assumptions of Guix's functional model (@pxref{Introduction}).
10499 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
10500 how to check the integrity of the store and attempt recovery from
10501 accidental modifications.
10504 The @code{(guix store)} module provides procedures to connect to the
10505 daemon, and to perform RPCs. These are described below. By default,
10506 @code{open-connection}, and thus all the @command{guix} commands,
10507 connect to the local daemon or to the URI specified by the
10508 @env{GUIX_DAEMON_SOCKET} environment variable.
10510 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
10511 When set, the value of this variable should be a file name or a URI
10512 designating the daemon endpoint. When it is a file name, it denotes a
10513 Unix-domain socket to connect to. In addition to file names, the
10514 supported URI schemes are:
10519 These are for Unix-domain sockets.
10520 @code{file:///var/guix/daemon-socket/socket} is equivalent to
10521 @file{/var/guix/daemon-socket/socket}.
10524 @cindex daemon, remote access
10525 @cindex remote access to the daemon
10526 @cindex daemon, cluster setup
10527 @cindex clusters, daemon setup
10528 These URIs denote connections over TCP/IP, without encryption nor
10529 authentication of the remote host. The URI must specify the host name
10530 and optionally a port number (by default port 44146 is used):
10533 guix://master.guix.example.org:1234
10536 This setup is suitable on local networks, such as clusters, where only
10537 trusted nodes may connect to the build daemon at
10538 @code{master.guix.example.org}.
10540 The @option{--listen} option of @command{guix-daemon} can be used to
10541 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
10542 @option{--listen}}).
10545 @cindex SSH access to build daemons
10546 These URIs allow you to connect to a remote daemon over SSH@. This
10547 feature requires Guile-SSH (@pxref{Requirements}) and a working
10548 @command{guile} binary in @env{PATH} on the destination machine. It
10549 supports public key and GSSAPI authentication. A typical URL might look
10553 ssh://charlie@@guix.example.org:22
10556 As for @command{guix copy}, the usual OpenSSH client configuration files
10557 are honored (@pxref{Invoking guix copy}).
10560 Additional URI schemes may be supported in the future.
10562 @c XXX: Remove this note when the protocol incurs fewer round trips
10563 @c and when (guix derivations) no longer relies on file system access.
10565 The ability to connect to remote build daemons is considered
10566 experimental as of @value{VERSION}. Please get in touch with us to
10567 share any problems or suggestions you may have (@pxref{Contributing}).
10571 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
10572 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
10573 @var{reserve-space?} is true, instruct it to reserve a little bit of
10574 extra space on the file system so that the garbage collector can still
10575 operate should the disk become full. Return a server object.
10577 @var{file} defaults to @code{%default-socket-path}, which is the normal
10578 location given the options that were passed to @command{configure}.
10581 @deffn {Scheme Procedure} close-connection @var{server}
10582 Close the connection to @var{server}.
10585 @defvr {Scheme Variable} current-build-output-port
10586 This variable is bound to a SRFI-39 parameter, which refers to the port
10587 where build and error logs sent by the daemon should be written.
10590 Procedures that make RPCs all take a server object as their first
10593 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
10594 @cindex invalid store items
10595 Return @code{#t} when @var{path} designates a valid store item and
10596 @code{#f} otherwise (an invalid item may exist on disk but still be
10597 invalid, for instance because it is the result of an aborted or failed
10600 A @code{&store-protocol-error} condition is raised if @var{path} is not
10601 prefixed by the store directory (@file{/gnu/store}).
10604 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
10605 Add @var{text} under file @var{name} in the store, and return its store
10606 path. @var{references} is the list of store paths referred to by the
10607 resulting store path.
10610 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
10612 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
10613 file names, or derivation/output pairs, using the specified
10614 @var{mode}---@code{(build-mode normal)} by default.
10617 Note that the @code{(guix monads)} module provides a monad as well as
10618 monadic versions of the above procedures, with the goal of making it
10619 more convenient to work with code that accesses the store (@pxref{The
10623 @i{This section is currently incomplete.}
10626 @section Derivations
10628 @cindex derivations
10629 Low-level build actions and the environment in which they are performed
10630 are represented by @dfn{derivations}. A derivation contains the
10631 following pieces of information:
10635 The outputs of the derivation---derivations produce at least one file or
10636 directory in the store, but may produce more.
10639 @cindex build-time dependencies
10640 @cindex dependencies, build-time
10641 The inputs of the derivations---i.e., its build-time dependencies---which may
10642 be other derivations or plain files in the store (patches, build scripts,
10646 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
10649 The file name of a build script in the store, along with the arguments
10653 A list of environment variables to be defined.
10657 @cindex derivation path
10658 Derivations allow clients of the daemon to communicate build actions to
10659 the store. They exist in two forms: as an in-memory representation,
10660 both on the client- and daemon-side, and as files in the store whose
10661 name end in @file{.drv}---these files are referred to as @dfn{derivation
10662 paths}. Derivations paths can be passed to the @code{build-derivations}
10663 procedure to perform the build actions they prescribe (@pxref{The
10666 @cindex fixed-output derivations
10667 Operations such as file downloads and version-control checkouts for
10668 which the expected content hash is known in advance are modeled as
10669 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
10670 of a fixed-output derivation are independent of its inputs---e.g., a
10671 source code download produces the same result regardless of the download
10672 method and tools being used.
10675 @cindex run-time dependencies
10676 @cindex dependencies, run-time
10677 The outputs of derivations---i.e., the build results---have a set of
10678 @dfn{references}, as reported by the @code{references} RPC or the
10679 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
10680 are the set of run-time dependencies of the build results. References are a
10681 subset of the inputs of the derivation; this subset is automatically computed
10682 by the build daemon by scanning all the files in the outputs.
10684 The @code{(guix derivations)} module provides a representation of
10685 derivations as Scheme objects, along with procedures to create and
10686 otherwise manipulate derivations. The lowest-level primitive to create
10687 a derivation is the @code{derivation} procedure:
10689 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
10690 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10691 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
10692 [#:system (%current-system)] [#:references-graphs #f] @
10693 [#:allowed-references #f] [#:disallowed-references #f] @
10694 [#:leaked-env-vars #f] [#:local-build? #f] @
10695 [#:substitutable? #t] [#:properties '()]
10696 Build a derivation with the given arguments, and return the resulting
10697 @code{<derivation>} object.
10699 When @var{hash} and @var{hash-algo} are given, a
10700 @dfn{fixed-output derivation} is created---i.e., one whose result is
10701 known in advance, such as a file download. If, in addition,
10702 @var{recursive?} is true, then that fixed output may be an executable
10703 file or a directory and @var{hash} must be the hash of an archive
10704 containing this output.
10706 When @var{references-graphs} is true, it must be a list of file
10707 name/store path pairs. In that case, the reference graph of each store
10708 path is exported in the build environment in the corresponding file, in
10709 a simple text format.
10711 When @var{allowed-references} is true, it must be a list of store items
10712 or outputs that the derivation's output may refer to. Likewise,
10713 @var{disallowed-references}, if true, must be a list of things the
10714 outputs may @emph{not} refer to.
10716 When @var{leaked-env-vars} is true, it must be a list of strings
10717 denoting environment variables that are allowed to ``leak'' from the
10718 daemon's environment to the build environment. This is only applicable
10719 to fixed-output derivations---i.e., when @var{hash} is true. The main
10720 use is to allow variables such as @code{http_proxy} to be passed to
10721 derivations that download files.
10723 When @var{local-build?} is true, declare that the derivation is not a
10724 good candidate for offloading and should rather be built locally
10725 (@pxref{Daemon Offload Setup}). This is the case for small derivations
10726 where the costs of data transfers would outweigh the benefits.
10728 When @var{substitutable?} is false, declare that substitutes of the
10729 derivation's output should not be used (@pxref{Substitutes}). This is
10730 useful, for instance, when building packages that capture details of the
10731 host CPU instruction set.
10733 @var{properties} must be an association list describing ``properties'' of the
10734 derivation. It is kept as-is, uninterpreted, in the derivation.
10738 Here's an example with a shell script as its builder, assuming
10739 @var{store} is an open connection to the daemon, and @var{bash} points
10740 to a Bash executable in the store:
10743 (use-modules (guix utils)
10745 (guix derivations))
10747 (let ((builder ; add the Bash script to the store
10748 (add-text-to-store store "my-builder.sh"
10749 "echo hello world > $out\n" '())))
10750 (derivation store "foo"
10751 bash `("-e" ,builder)
10752 #:inputs `((,bash) (,builder))
10753 #:env-vars '(("HOME" . "/homeless"))))
10754 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
10757 As can be guessed, this primitive is cumbersome to use directly. A
10758 better approach is to write build scripts in Scheme, of course! The
10759 best course of action for that is to write the build code as a
10760 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
10761 information, @pxref{G-Expressions}.
10763 Once upon a time, @code{gexp->derivation} did not exist and constructing
10764 derivations with build code written in Scheme was achieved with
10765 @code{build-expression->derivation}, documented below. This procedure
10766 is now deprecated in favor of the much nicer @code{gexp->derivation}.
10768 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
10769 @var{name} @var{exp} @
10770 [#:system (%current-system)] [#:inputs '()] @
10771 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10772 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
10773 [#:references-graphs #f] [#:allowed-references #f] @
10774 [#:disallowed-references #f] @
10775 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
10776 Return a derivation that executes Scheme expression @var{exp} as a
10777 builder for derivation @var{name}. @var{inputs} must be a list of
10778 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
10779 @code{"out"} is assumed. @var{modules} is a list of names of Guile
10780 modules from the current search path to be copied in the store,
10781 compiled, and made available in the load path during the execution of
10782 @var{exp}---e.g., @code{((guix build utils) (guix build
10783 gnu-build-system))}.
10785 @var{exp} is evaluated in an environment where @code{%outputs} is bound
10786 to a list of output/path pairs, and where @code{%build-inputs} is bound
10787 to a list of string/output-path pairs made from @var{inputs}.
10788 Optionally, @var{env-vars} is a list of string pairs specifying the name
10789 and value of environment variables visible to the builder. The builder
10790 terminates by passing the result of @var{exp} to @code{exit}; thus, when
10791 @var{exp} returns @code{#f}, the build is considered to have failed.
10793 @var{exp} is built using @var{guile-for-build} (a derivation). When
10794 @var{guile-for-build} is omitted or is @code{#f}, the value of the
10795 @code{%guile-for-build} fluid is used instead.
10797 See the @code{derivation} procedure for the meaning of
10798 @var{references-graphs}, @var{allowed-references},
10799 @var{disallowed-references}, @var{local-build?}, and
10800 @var{substitutable?}.
10804 Here's an example of a single-output derivation that creates a directory
10805 containing one file:
10808 (let ((builder '(let ((out (assoc-ref %outputs "out")))
10809 (mkdir out) ; create /gnu/store/@dots{}-goo
10810 (call-with-output-file (string-append out "/test")
10812 (display '(hello guix) p))))))
10813 (build-expression->derivation store "goo" builder))
10815 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
10819 @node The Store Monad
10820 @section The Store Monad
10824 The procedures that operate on the store described in the previous
10825 sections all take an open connection to the build daemon as their first
10826 argument. Although the underlying model is functional, they either have
10827 side effects or depend on the current state of the store.
10829 The former is inconvenient: the connection to the build daemon has to be
10830 carried around in all those functions, making it impossible to compose
10831 functions that do not take that parameter with functions that do. The
10832 latter can be problematic: since store operations have side effects
10833 and/or depend on external state, they have to be properly sequenced.
10835 @cindex monadic values
10836 @cindex monadic functions
10837 This is where the @code{(guix monads)} module comes in. This module
10838 provides a framework for working with @dfn{monads}, and a particularly
10839 useful monad for our uses, the @dfn{store monad}. Monads are a
10840 construct that allows two things: associating ``context'' with values
10841 (in our case, the context is the store), and building sequences of
10842 computations (here computations include accesses to the store). Values
10843 in a monad---values that carry this additional context---are called
10844 @dfn{monadic values}; procedures that return such values are called
10845 @dfn{monadic procedures}.
10847 Consider this ``normal'' procedure:
10850 (define (sh-symlink store)
10851 ;; Return a derivation that symlinks the 'bash' executable.
10852 (let* ((drv (package-derivation store bash))
10853 (out (derivation->output-path drv))
10854 (sh (string-append out "/bin/bash")))
10855 (build-expression->derivation store "sh"
10856 `(symlink ,sh %output))))
10859 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
10860 as a monadic function:
10863 (define (sh-symlink)
10864 ;; Same, but return a monadic value.
10865 (mlet %store-monad ((drv (package->derivation bash)))
10866 (gexp->derivation "sh"
10867 #~(symlink (string-append #$drv "/bin/bash")
10871 There are several things to note in the second version: the @code{store}
10872 parameter is now implicit and is ``threaded'' in the calls to the
10873 @code{package->derivation} and @code{gexp->derivation} monadic
10874 procedures, and the monadic value returned by @code{package->derivation}
10875 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
10877 As it turns out, the call to @code{package->derivation} can even be
10878 omitted since it will take place implicitly, as we will see later
10879 (@pxref{G-Expressions}):
10882 (define (sh-symlink)
10883 (gexp->derivation "sh"
10884 #~(symlink (string-append #$bash "/bin/bash")
10889 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
10890 @c for the funny quote.
10891 Calling the monadic @code{sh-symlink} has no effect. As someone once
10892 said, ``you exit a monad like you exit a building on fire: by running''.
10893 So, to exit the monad and get the desired effect, one must use
10894 @code{run-with-store}:
10897 (run-with-store (open-connection) (sh-symlink))
10898 @result{} /gnu/store/...-sh-symlink
10901 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
10902 new ``commands'' to make it easier to deal with monadic procedures:
10903 @code{run-in-store}, and @code{enter-store-monad} (@pxref{Using Guix
10904 Interactively}). The former is used
10905 to ``run'' a single monadic value through the store:
10908 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
10909 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10912 The latter enters a recursive REPL, where all the return values are
10913 automatically run through the store:
10916 scheme@@(guile-user)> ,enter-store-monad
10917 store-monad@@(guile-user) [1]> (package->derivation hello)
10918 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10919 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
10920 $3 = "/gnu/store/@dots{}-foo"
10921 store-monad@@(guile-user) [1]> ,q
10922 scheme@@(guile-user)>
10926 Note that non-monadic values cannot be returned in the
10927 @code{store-monad} REPL.
10929 Other meta-commands are available at the REPL, such as @code{,build} to
10930 build a file-like object (@pxref{Using Guix Interactively}).
10932 The main syntactic forms to deal with monads in general are provided by
10933 the @code{(guix monads)} module and are described below.
10935 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
10936 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
10940 @deffn {Scheme Syntax} return @var{val}
10941 Return a monadic value that encapsulates @var{val}.
10944 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
10945 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
10946 procedures @var{mproc}@dots{}@footnote{This operation is commonly
10947 referred to as ``bind'', but that name denotes an unrelated procedure in
10948 Guile. Thus we use this somewhat cryptic symbol inherited from the
10949 Haskell language.}. There can be one @var{mproc} or several of them, as
10954 (with-monad %state-monad
10956 (lambda (x) (return (+ 1 x)))
10957 (lambda (x) (return (* 2 x)))))
10961 @result{} some-state
10965 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
10967 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
10969 Bind the variables @var{var} to the monadic values @var{mval} in
10970 @var{body}, which is a sequence of expressions. As with the bind
10971 operator, this can be thought of as ``unpacking'' the raw, non-monadic
10972 value ``contained'' in @var{mval} and making @var{var} refer to that
10973 raw, non-monadic value within the scope of the @var{body}. The form
10974 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
10975 @var{val}, as per @code{let}. The binding operations occur in sequence
10976 from left to right. The last expression of @var{body} must be a monadic
10977 expression, and its result will become the result of the @code{mlet} or
10978 @code{mlet*} when run in the @var{monad}.
10980 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
10981 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
10984 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
10985 Bind @var{mexp} and the following monadic expressions in sequence,
10986 returning the result of the last expression. Every expression in the
10987 sequence must be a monadic expression.
10989 This is akin to @code{mlet}, except that the return values of the
10990 monadic expressions are ignored. In that sense, it is analogous to
10991 @code{begin}, but applied to monadic expressions.
10994 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
10995 When @var{condition} is true, evaluate the sequence of monadic
10996 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
10997 @var{condition} is false, return @code{*unspecified*} in the current
10998 monad. Every expression in the sequence must be a monadic expression.
11001 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
11002 When @var{condition} is false, evaluate the sequence of monadic
11003 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
11004 @var{condition} is true, return @code{*unspecified*} in the current
11005 monad. Every expression in the sequence must be a monadic expression.
11008 @cindex state monad
11009 The @code{(guix monads)} module provides the @dfn{state monad}, which
11010 allows an additional value---the state---to be @emph{threaded} through
11011 monadic procedure calls.
11013 @defvr {Scheme Variable} %state-monad
11014 The state monad. Procedures in the state monad can access and change
11015 the state that is threaded.
11017 Consider the example below. The @code{square} procedure returns a value
11018 in the state monad. It returns the square of its argument, but also
11019 increments the current state value:
11023 (mlet %state-monad ((count (current-state)))
11024 (mbegin %state-monad
11025 (set-current-state (+ 1 count))
11026 (return (* x x)))))
11028 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
11033 When ``run'' through @code{%state-monad}, we obtain that additional state
11034 value, which is the number of @code{square} calls.
11037 @deffn {Monadic Procedure} current-state
11038 Return the current state as a monadic value.
11041 @deffn {Monadic Procedure} set-current-state @var{value}
11042 Set the current state to @var{value} and return the previous state as a
11046 @deffn {Monadic Procedure} state-push @var{value}
11047 Push @var{value} to the current state, which is assumed to be a list,
11048 and return the previous state as a monadic value.
11051 @deffn {Monadic Procedure} state-pop
11052 Pop a value from the current state and return it as a monadic value.
11053 The state is assumed to be a list.
11056 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
11057 Run monadic value @var{mval} starting with @var{state} as the initial
11058 state. Return two values: the resulting value, and the resulting state.
11061 The main interface to the store monad, provided by the @code{(guix
11062 store)} module, is as follows.
11064 @defvr {Scheme Variable} %store-monad
11065 The store monad---an alias for @code{%state-monad}.
11067 Values in the store monad encapsulate accesses to the store. When its
11068 effect is needed, a value of the store monad must be ``evaluated'' by
11069 passing it to the @code{run-with-store} procedure (see below).
11072 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
11073 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
11074 open store connection.
11077 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
11078 Return as a monadic value the absolute file name in the store of the file
11079 containing @var{text}, a string. @var{references} is a list of store items that the
11080 resulting text file refers to; it defaults to the empty list.
11083 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
11084 Return as a monadic value the absolute file name in the store of the file
11085 containing @var{data}, a bytevector. @var{references} is a list of store
11086 items that the resulting binary file refers to; it defaults to the empty list.
11089 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
11090 [#:recursive? #t] [#:select? (const #t)]
11091 Return the name of @var{file} once interned in the store. Use
11092 @var{name} as its store name, or the basename of @var{file} if
11093 @var{name} is omitted.
11095 When @var{recursive?} is true, the contents of @var{file} are added
11096 recursively; if @var{file} designates a flat file and @var{recursive?}
11097 is true, its contents are added, and its permission bits are kept.
11099 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11100 @var{stat})} for each directory entry, where @var{file} is the entry's
11101 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11102 entries for which @var{select?} does not return true.
11104 The example below adds a file to the store, under two different names:
11107 (run-with-store (open-connection)
11108 (mlet %store-monad ((a (interned-file "README"))
11109 (b (interned-file "README" "LEGU-MIN")))
11110 (return (list a b))))
11112 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
11117 The @code{(guix packages)} module exports the following package-related
11118 monadic procedures:
11120 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
11121 [#:system (%current-system)] [#:target #f] @
11123 Return as a monadic
11124 value in the absolute file name of @var{file} within the @var{output}
11125 directory of @var{package}. When @var{file} is omitted, return the name
11126 of the @var{output} directory of @var{package}. When @var{target} is
11127 true, use it as a cross-compilation target triplet.
11129 Note that this procedure does @emph{not} build @var{package}. Thus, the
11130 result might or might not designate an existing file. We recommend not
11131 using this procedure unless you know what you are doing.
11134 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
11135 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
11136 @var{target} [@var{system}]
11137 Monadic version of @code{package-derivation} and
11138 @code{package-cross-derivation} (@pxref{Defining Packages}).
11142 @node G-Expressions
11143 @section G-Expressions
11145 @cindex G-expression
11146 @cindex build code quoting
11147 So we have ``derivations'', which represent a sequence of build actions
11148 to be performed to produce an item in the store (@pxref{Derivations}).
11149 These build actions are performed when asking the daemon to actually
11150 build the derivations; they are run by the daemon in a container
11151 (@pxref{Invoking guix-daemon}).
11153 @cindex code staging
11154 @cindex staging, of code
11155 @cindex strata of code
11156 It should come as no surprise that we like to write these build actions
11157 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
11158 code@footnote{The term @dfn{stratum} in this context was coined by
11159 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
11160 Kiselyov, who has written insightful
11161 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
11162 on this topic}, refers to this kind of code generation as
11163 @dfn{staging}.}: the ``host code''---code that defines packages, talks
11164 to the daemon, etc.---and the ``build code''---code that actually
11165 performs build actions, such as making directories, invoking
11166 @command{make}, and so on (@pxref{Build Phases}).
11168 To describe a derivation and its build actions, one typically needs to
11169 embed build code inside host code. It boils down to manipulating build
11170 code as data, and the homoiconicity of Scheme---code has a direct
11171 representation as data---comes in handy for that. But we need more than
11172 the normal @code{quasiquote} mechanism in Scheme to construct build
11175 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
11176 S-expressions adapted to build expressions. G-expressions, or
11177 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
11178 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
11179 @code{#$}, and @code{#$@@}), which are comparable to
11180 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
11181 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
11182 GNU Guile Reference Manual}). However, there are major differences:
11186 Gexps are meant to be written to a file and run or manipulated by other
11190 When a high-level object such as a package or derivation is unquoted
11191 inside a gexp, the result is as if its output file name had been
11195 Gexps carry information about the packages or derivations they refer to,
11196 and these dependencies are automatically added as inputs to the build
11197 processes that use them.
11200 @cindex lowering, of high-level objects in gexps
11201 This mechanism is not limited to package and derivation
11202 objects: @dfn{compilers} able to ``lower'' other high-level objects to
11203 derivations or files in the store can be defined,
11204 such that these objects can also be inserted
11205 into gexps. For example, a useful type of high-level objects that can be
11206 inserted in a gexp is ``file-like objects'', which make it easy to
11207 add files to the store and to refer to them in
11208 derivations and such (see @code{local-file} and @code{plain-file}
11211 To illustrate the idea, here is an example of a gexp:
11218 (symlink (string-append #$coreutils "/bin/ls")
11222 This gexp can be passed to @code{gexp->derivation}; we obtain a
11223 derivation that builds a directory containing exactly one symlink to
11224 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
11227 (gexp->derivation "the-thing" build-exp)
11230 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
11231 substituted to the reference to the @var{coreutils} package in the
11232 actual build code, and @var{coreutils} is automatically made an input to
11233 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
11234 output)}) is replaced by a string containing the directory name of the
11235 output of the derivation.
11237 @cindex cross compilation
11238 In a cross-compilation context, it is useful to distinguish between
11239 references to the @emph{native} build of a package---that can run on the
11240 host---versus references to cross builds of a package. To that end, the
11241 @code{#+} plays the same role as @code{#$}, but is a reference to a
11242 native package build:
11245 (gexp->derivation "vi"
11248 (mkdir (string-append #$output "/bin"))
11249 (system* (string-append #+coreutils "/bin/ln")
11251 (string-append #$emacs "/bin/emacs")
11252 (string-append #$output "/bin/vi")))
11253 #:target "aarch64-linux-gnu")
11257 In the example above, the native build of @var{coreutils} is used, so
11258 that @command{ln} can actually run on the host; but then the
11259 cross-compiled build of @var{emacs} is referenced.
11261 @cindex imported modules, for gexps
11262 @findex with-imported-modules
11263 Another gexp feature is @dfn{imported modules}: sometimes you want to be
11264 able to use certain Guile modules from the ``host environment'' in the
11265 gexp, so those modules should be imported in the ``build environment''.
11266 The @code{with-imported-modules} form allows you to express that:
11269 (let ((build (with-imported-modules '((guix build utils))
11271 (use-modules (guix build utils))
11272 (mkdir-p (string-append #$output "/bin"))))))
11273 (gexp->derivation "empty-dir"
11276 (display "success!\n")
11281 In this example, the @code{(guix build utils)} module is automatically
11282 pulled into the isolated build environment of our gexp, such that
11283 @code{(use-modules (guix build utils))} works as expected.
11285 @cindex module closure
11286 @findex source-module-closure
11287 Usually you want the @emph{closure} of the module to be imported---i.e.,
11288 the module itself and all the modules it depends on---rather than just
11289 the module; failing to do that, attempts to use the module will fail
11290 because of missing dependent modules. The @code{source-module-closure}
11291 procedure computes the closure of a module by looking at its source file
11292 headers, which comes in handy in this case:
11295 (use-modules (guix modules)) ;for 'source-module-closure'
11297 (with-imported-modules (source-module-closure
11298 '((guix build utils)
11299 (gnu build image)))
11300 (gexp->derivation "something-with-vms"
11302 (use-modules (guix build utils)
11307 @cindex extensions, for gexps
11308 @findex with-extensions
11309 In the same vein, sometimes you want to import not just pure-Scheme
11310 modules, but also ``extensions'' such as Guile bindings to C libraries
11311 or other ``full-blown'' packages. Say you need the @code{guile-json}
11312 package available on the build side, here's how you would do it:
11315 (use-modules (gnu packages guile)) ;for 'guile-json'
11317 (with-extensions (list guile-json)
11318 (gexp->derivation "something-with-json"
11320 (use-modules (json))
11324 The syntactic form to construct gexps is summarized below.
11326 @deffn {Scheme Syntax} #~@var{exp}
11327 @deffnx {Scheme Syntax} (gexp @var{exp})
11328 Return a G-expression containing @var{exp}. @var{exp} may contain one
11329 or more of the following forms:
11333 @itemx (ungexp @var{obj})
11334 Introduce a reference to @var{obj}. @var{obj} may have one of the
11335 supported types, for example a package or a
11336 derivation, in which case the @code{ungexp} form is replaced by its
11337 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
11339 If @var{obj} is a list, it is traversed and references to supported
11340 objects are substituted similarly.
11342 If @var{obj} is another gexp, its contents are inserted and its
11343 dependencies are added to those of the containing gexp.
11345 If @var{obj} is another kind of object, it is inserted as is.
11347 @item #$@var{obj}:@var{output}
11348 @itemx (ungexp @var{obj} @var{output})
11349 This is like the form above, but referring explicitly to the
11350 @var{output} of @var{obj}---this is useful when @var{obj} produces
11351 multiple outputs (@pxref{Packages with Multiple Outputs}).
11354 @itemx #+@var{obj}:output
11355 @itemx (ungexp-native @var{obj})
11356 @itemx (ungexp-native @var{obj} @var{output})
11357 Same as @code{ungexp}, but produces a reference to the @emph{native}
11358 build of @var{obj} when used in a cross compilation context.
11360 @item #$output[:@var{output}]
11361 @itemx (ungexp output [@var{output}])
11362 Insert a reference to derivation output @var{output}, or to the main
11363 output when @var{output} is omitted.
11365 This only makes sense for gexps passed to @code{gexp->derivation}.
11367 @item #$@@@var{lst}
11368 @itemx (ungexp-splicing @var{lst})
11369 Like the above, but splices the contents of @var{lst} inside the
11372 @item #+@@@var{lst}
11373 @itemx (ungexp-native-splicing @var{lst})
11374 Like the above, but refers to native builds of the objects listed in
11379 G-expressions created by @code{gexp} or @code{#~} are run-time objects
11380 of the @code{gexp?} type (see below).
11383 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
11384 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
11385 in their execution environment.
11387 Each item in @var{modules} can be the name of a module, such as
11388 @code{(guix build utils)}, or it can be a module name, followed by an
11389 arrow, followed by a file-like object:
11392 `((guix build utils)
11394 ((guix config) => ,(scheme-file "config.scm"
11395 #~(define-module @dots{}))))
11399 In the example above, the first two modules are taken from the search
11400 path, and the last one is created from the given file-like object.
11402 This form has @emph{lexical} scope: it has an effect on the gexps
11403 directly defined in @var{body}@dots{}, but not on those defined, say, in
11404 procedures called from @var{body}@dots{}.
11407 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
11408 Mark the gexps defined in @var{body}@dots{} as requiring
11409 @var{extensions} in their build and execution environment.
11410 @var{extensions} is typically a list of package objects such as those
11411 defined in the @code{(gnu packages guile)} module.
11413 Concretely, the packages listed in @var{extensions} are added to the
11414 load path while compiling imported modules in @var{body}@dots{}; they
11415 are also added to the load path of the gexp returned by
11419 @deffn {Scheme Procedure} gexp? @var{obj}
11420 Return @code{#t} if @var{obj} is a G-expression.
11423 G-expressions are meant to be written to disk, either as code building
11424 some derivation, or as plain files in the store. The monadic procedures
11425 below allow you to do that (@pxref{The Store Monad}, for more
11426 information about monads).
11428 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
11429 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
11430 [#:hash #f] [#:hash-algo #f] @
11431 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
11432 [#:module-path @code{%load-path}] @
11433 [#:effective-version "2.2"] @
11434 [#:references-graphs #f] [#:allowed-references #f] @
11435 [#:disallowed-references #f] @
11436 [#:leaked-env-vars #f] @
11437 [#:script-name (string-append @var{name} "-builder")] @
11438 [#:deprecation-warnings #f] @
11439 [#:local-build? #f] [#:substitutable? #t] @
11440 [#:properties '()] [#:guile-for-build #f]
11441 Return a derivation @var{name} that runs @var{exp} (a gexp) with
11442 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
11443 stored in a file called @var{script-name}. When @var{target} is true,
11444 it is used as the cross-compilation target triplet for packages referred
11447 @var{modules} is deprecated in favor of @code{with-imported-modules}.
11449 make @var{modules} available in the evaluation context of @var{exp};
11450 @var{modules} is a list of names of Guile modules searched in
11451 @var{module-path} to be copied in the store, compiled, and made available in
11452 the load path during the execution of @var{exp}---e.g., @code{((guix
11453 build utils) (guix build gnu-build-system))}.
11455 @var{effective-version} determines the string to use when adding extensions of
11456 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
11458 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
11461 When @var{references-graphs} is true, it must be a list of tuples of one of the
11465 (@var{file-name} @var{package})
11466 (@var{file-name} @var{package} @var{output})
11467 (@var{file-name} @var{derivation})
11468 (@var{file-name} @var{derivation} @var{output})
11469 (@var{file-name} @var{store-item})
11472 The right-hand-side of each element of @var{references-graphs} is automatically made
11473 an input of the build process of @var{exp}. In the build environment, each
11474 @var{file-name} contains the reference graph of the corresponding item, in a simple
11477 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
11478 In the latter case, the list denotes store items that the result is allowed to
11479 refer to. Any reference to another store item will lead to a build error.
11480 Similarly for @var{disallowed-references}, which can list items that must not be
11481 referenced by the outputs.
11483 @var{deprecation-warnings} determines whether to show deprecation warnings while
11484 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
11486 The other arguments are as for @code{derivation} (@pxref{Derivations}).
11489 @cindex file-like objects
11490 The @code{local-file}, @code{plain-file}, @code{computed-file},
11491 @code{program-file}, and @code{scheme-file} procedures below return
11492 @dfn{file-like objects}. That is, when unquoted in a G-expression,
11493 these objects lead to a file in the store. Consider this G-expression:
11496 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
11497 #$(local-file "/tmp/my-nscd.conf"))
11500 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
11501 to the store. Once expanded, for instance @i{via}
11502 @code{gexp->derivation}, the G-expression refers to that copy under
11503 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
11504 does not have any effect on what the G-expression does.
11505 @code{plain-file} can be used similarly; it differs in that the file
11506 content is directly passed as a string.
11508 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
11509 [#:recursive? #f] [#:select? (const #t)]
11510 Return an object representing local file @var{file} to add to the store;
11511 this object can be used in a gexp. If @var{file} is a literal string
11512 denoting a relative file name, it is looked up relative to the source
11513 file where it appears; if @var{file} is not a literal string, it is
11514 looked up relative to the current working directory at run time.
11515 @var{file} will be added to the store under @var{name}--by default the
11516 base name of @var{file}.
11518 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
11519 designates a flat file and @var{recursive?} is true, its contents are added, and its
11520 permission bits are kept.
11522 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11523 @var{stat})} for each directory entry, where @var{file} is the entry's
11524 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11525 entries for which @var{select?} does not return true.
11527 This is the declarative counterpart of the @code{interned-file} monadic
11528 procedure (@pxref{The Store Monad, @code{interned-file}}).
11531 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
11532 Return an object representing a text file called @var{name} with the given
11533 @var{content} (a string or a bytevector) to be added to the store.
11535 This is the declarative counterpart of @code{text-file}.
11538 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
11539 [#:local-build? #t]
11541 Return an object representing the store item @var{name}, a file or
11542 directory computed by @var{gexp}. When @var{local-build?} is true (the
11543 default), the derivation is built locally. @var{options} is a list of
11544 additional arguments to pass to @code{gexp->derivation}.
11546 This is the declarative counterpart of @code{gexp->derivation}.
11549 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
11550 [#:guile (default-guile)] [#:module-path %load-path] @
11551 [#:system (%current-system)] [#:target #f]
11552 Return an executable script @var{name} that runs @var{exp} using
11553 @var{guile}, with @var{exp}'s imported modules in its search path.
11554 Look up @var{exp}'s modules in @var{module-path}.
11556 The example below builds a script that simply invokes the @command{ls}
11560 (use-modules (guix gexp) (gnu packages base))
11562 (gexp->script "list-files"
11563 #~(execl #$(file-append coreutils "/bin/ls")
11567 When ``running'' it through the store (@pxref{The Store Monad,
11568 @code{run-with-store}}), we obtain a derivation that produces an
11569 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
11572 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
11574 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
11578 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
11579 [#:guile #f] [#:module-path %load-path]
11580 Return an object representing the executable store item @var{name} that
11581 runs @var{gexp}. @var{guile} is the Guile package used to execute that
11582 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
11584 This is the declarative counterpart of @code{gexp->script}.
11587 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
11588 [#:set-load-path? #t] [#:module-path %load-path] @
11590 [#:guile (default-guile)]
11591 Return a derivation that builds a file @var{name} containing @var{exp}.
11592 When @var{splice?} is true, @var{exp} is considered to be a list of
11593 expressions that will be spliced in the resulting file.
11595 When @var{set-load-path?} is true, emit code in the resulting file to
11596 set @code{%load-path} and @code{%load-compiled-path} to honor
11597 @var{exp}'s imported modules. Look up @var{exp}'s modules in
11600 The resulting file holds references to all the dependencies of @var{exp}
11601 or a subset thereof.
11604 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
11605 [#:splice? #f] [#:set-load-path? #t]
11606 Return an object representing the Scheme file @var{name} that contains
11609 This is the declarative counterpart of @code{gexp->file}.
11612 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
11613 Return as a monadic value a derivation that builds a text file
11614 containing all of @var{text}. @var{text} may list, in addition to
11615 strings, objects of any type that can be used in a gexp: packages,
11616 derivations, local file objects, etc. The resulting store file holds
11617 references to all these.
11619 This variant should be preferred over @code{text-file} anytime the file
11620 to create will reference items from the store. This is typically the
11621 case when building a configuration file that embeds store file names,
11625 (define (profile.sh)
11626 ;; Return the name of a shell script in the store that
11627 ;; initializes the 'PATH' environment variable.
11628 (text-file* "profile.sh"
11629 "export PATH=" coreutils "/bin:"
11630 grep "/bin:" sed "/bin\n"))
11633 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
11634 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
11635 preventing them from being garbage-collected during its lifetime.
11638 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
11639 Return an object representing store file @var{name} containing
11640 @var{text}. @var{text} is a sequence of strings and file-like objects,
11644 (mixed-text-file "profile"
11645 "export PATH=" coreutils "/bin:" grep "/bin")
11648 This is the declarative counterpart of @code{text-file*}.
11651 @deffn {Scheme Procedure} file-union @var{name} @var{files}
11652 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
11653 Each item in @var{files} must be a two-element list where the first element is the
11654 file name to use in the new directory, and the second element is a gexp
11655 denoting the target file. Here's an example:
11659 `(("hosts" ,(plain-file "hosts"
11660 "127.0.0.1 localhost"))
11661 ("bashrc" ,(plain-file "bashrc"
11662 "alias ls='ls --color=auto'"))))
11665 This yields an @code{etc} directory containing these two files.
11668 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
11669 Return a directory that is the union of @var{things}, where @var{things} is a list of
11670 file-like objects denoting directories. For example:
11673 (directory-union "guile+emacs" (list guile emacs))
11676 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
11679 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
11680 Return a file-like object that expands to the concatenation of @var{obj}
11681 and @var{suffix}, where @var{obj} is a lowerable object and each
11682 @var{suffix} is a string.
11684 As an example, consider this gexp:
11687 (gexp->script "run-uname"
11688 #~(system* #$(file-append coreutils
11692 The same effect could be achieved with:
11695 (gexp->script "run-uname"
11696 #~(system* (string-append #$coreutils
11700 There is one difference though: in the @code{file-append} case, the
11701 resulting script contains the absolute file name as a string, whereas in
11702 the second case, the resulting script contains a @code{(string-append
11703 @dots{})} expression to construct the file name @emph{at run time}.
11706 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
11707 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
11708 Bind @var{system} to the currently targeted system---e.g.,
11709 @code{"x86_64-linux"}---within @var{body}.
11711 In the second case, additionally bind @var{target} to the current
11712 cross-compilation target---a GNU triplet such as
11713 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
11716 @code{let-system} is useful in the occasional case where the object
11717 spliced into the gexp depends on the target system, as in this example:
11721 #+(let-system system
11722 (cond ((string-prefix? "armhf-" system)
11723 (file-append qemu "/bin/qemu-system-arm"))
11724 ((string-prefix? "x86_64-" system)
11725 (file-append qemu "/bin/qemu-system-x86_64"))
11727 (error "dunno!"))))
11728 "-net" "user" #$image)
11732 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
11733 This macro is similar to the @code{parameterize} form for
11734 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
11735 Guile Reference Manual}). The key difference is that it takes effect
11736 when the file-like object returned by @var{exp} is lowered to a
11737 derivation or store item.
11739 A typical use of @code{with-parameters} is to force the system in effect
11740 for a given object:
11743 (with-parameters ((%current-system "i686-linux"))
11747 The example above returns an object that corresponds to the i686 build
11748 of Coreutils, regardless of the current value of @code{%current-system}.
11752 Of course, in addition to gexps embedded in ``host'' code, there are
11753 also modules containing build tools. To make it clear that they are
11754 meant to be used in the build stratum, these modules are kept in the
11755 @code{(guix build @dots{})} name space.
11757 @cindex lowering, of high-level objects in gexps
11758 Internally, high-level objects are @dfn{lowered}, using their compiler,
11759 to either derivations or store items. For instance, lowering a package
11760 yields a derivation, and lowering a @code{plain-file} yields a store
11761 item. This is achieved using the @code{lower-object} monadic procedure.
11763 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
11765 Return as a value in @code{%store-monad} the derivation or store item
11766 corresponding to @var{obj} for @var{system}, cross-compiling for
11767 @var{target} if @var{target} is true. @var{obj} must be an object that
11768 has an associated gexp compiler, such as a @code{<package>}.
11771 @deffn {Procedure} gexp->approximate-sexp @var{gexp}
11772 Sometimes, it may be useful to convert a G-exp into a S-exp. For
11773 example, some linters (@pxref{Invoking guix lint}) peek into the build
11774 phases of a package to detect potential problems. This conversion can
11775 be achieved with this procedure. However, some information can be lost
11776 in the process. More specifically, lowerable objects will be silently
11777 replaced with some arbitrary object -- currently the list
11778 @code{(*approximate*)}, but this may change.
11781 @node Invoking guix repl
11782 @section Invoking @command{guix repl}
11784 @cindex REPL, read-eval-print loop, script
11785 The @command{guix repl} command makes it easier to program Guix in Guile
11786 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
11787 programming (@pxref{Using Guile Interactively,,, guile,
11788 GNU Guile Reference Manual}), or by running Guile scripts
11789 (@pxref{Running Guile Scripts,,, guile,
11790 GNU Guile Reference Manual}).
11791 Compared to just launching the @command{guile}
11792 command, @command{guix repl} guarantees that all the Guix modules and all its
11793 dependencies are available in the search path.
11795 The general syntax is:
11798 guix repl @var{options} [@var{file} @var{args}]
11801 When a @var{file} argument is provided, @var{file} is
11802 executed as a Guile scripts:
11805 guix repl my-script.scm
11808 To pass arguments to the script, use @code{--} to prevent them from
11809 being interpreted as arguments to @command{guix repl} itself:
11812 guix repl -- my-script.scm --input=foo.txt
11815 To make a script executable directly from the shell, using the guix
11816 executable that is on the user's search path, add the following two
11817 lines at the top of the script:
11820 @code{#!/usr/bin/env -S guix repl --}
11824 Without a file name argument, a Guile REPL is started, allowing for
11825 interactive use (@pxref{Using Guix Interactively}):
11829 scheme@@(guile-user)> ,use (gnu packages base)
11830 scheme@@(guile-user)> coreutils
11831 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
11835 In addition, @command{guix repl} implements a simple machine-readable REPL
11836 protocol for use by @code{(guix inferior)}, a facility to interact with
11837 @dfn{inferiors}, separate processes running a potentially different revision
11840 The available options are as follows:
11843 @item --type=@var{type}
11844 @itemx -t @var{type}
11845 Start a REPL of the given @var{TYPE}, which can be one of the following:
11849 This is default, and it spawns a standard full-featured Guile REPL.
11851 Spawn a REPL that uses the machine-readable protocol. This is the protocol
11852 that the @code{(guix inferior)} module speaks.
11855 @item --listen=@var{endpoint}
11856 By default, @command{guix repl} reads from standard input and writes to
11857 standard output. When this option is passed, it will instead listen for
11858 connections on @var{endpoint}. Here are examples of valid options:
11861 @item --listen=tcp:37146
11862 Accept connections on localhost on port 37146.
11864 @item --listen=unix:/tmp/socket
11865 Accept connections on the Unix-domain socket @file{/tmp/socket}.
11868 @item --load-path=@var{directory}
11869 @itemx -L @var{directory}
11870 Add @var{directory} to the front of the package module search path
11871 (@pxref{Package Modules}).
11873 This allows users to define their own packages and make them visible to
11874 the script or REPL.
11877 Inhibit loading of the @file{~/.guile} file. By default, that
11878 configuration file is loaded when spawning a @code{guile} REPL.
11881 @node Using Guix Interactively
11882 @section Using Guix Interactively
11884 @cindex interactive use
11885 @cindex REPL, read-eval-print loop
11886 The @command{guix repl} command gives you access to a warm and friendly
11887 @dfn{read-eval-print loop} (REPL) (@pxref{Invoking guix repl}). If
11888 you're getting into Guix programming---defining your own packages,
11889 writing manifests, defining services for Guix System or Guix Home,
11890 etc.---you will surely find it convenient to toy with ideas at the REPL.
11892 If you use Emacs, the most convenient way to do that is with Geiser
11893 (@pxref{The Perfect Setup}), but you do not have to use Emacs to enjoy
11894 the REPL@. When using @command{guix repl} or @command{guile} in the
11895 terminal, we recommend using Readline for completion and Colorized to
11896 get colorful output. To do that, you can run:
11899 guix install guile guile-readline guile-colorized
11903 ... and then create a @file{.guile} file in your home directory containing
11907 (use-modules (ice-9 readline) (ice-9 colorized))
11909 (activate-readline)
11910 (activate-colorized)
11913 The REPL lets you evaluate Scheme code; you type a Scheme expression at
11914 the prompt, and the REPL prints what it evaluates to:
11918 scheme@@(guix-user)> (+ 2 3)
11920 scheme@@(guix-user)> (string-append "a" "b")
11924 It becomes interesting when you start fiddling with Guix at the REPL.
11925 The first thing you'll want to do is to ``import'' the @code{(guix)}
11926 module, which gives access to the main part of the programming
11927 interface, and perhaps a bunch of useful Guix modules. You could type
11928 @code{(use-modules (guix))}, which is valid Scheme code to import a
11929 module (@pxref{Using Guile Modules,,, guile, GNU Guile Reference
11930 Manual}), but the REPL provides the @code{use} @dfn{command} as a
11931 shorthand notation (@pxref{REPL Commands,,, guile, GNU Guile Reference
11935 scheme@@(guix-user)> ,use (guix)
11936 scheme@@(guix-user)> ,use (gnu packages base)
11939 Notice that REPL commands are introduced by a leading comma. A REPL
11940 command like @code{use} is not valid Scheme code; it's interpreted
11941 specially by the REPL.
11943 Guix extends the Guile REPL with additional commands for convenience.
11944 Among those, the @code{build} command comes in handy: it ensures that
11945 the given file-like object is built, building it if needed, and returns
11946 its output file name(s). In the example below, we build the
11947 @code{coreutils} and @code{grep} packages, as well as a ``computed
11948 file'' (@pxref{G-Expressions, @code{computed-file}}), and we use the
11949 @code{scandir} procedure to list the files in Grep's @code{/bin}
11953 scheme@@(guix-user)> ,build coreutils
11954 $1 = "/gnu/store/@dots{}-coreutils-8.32-debug"
11955 $2 = "/gnu/store/@dots{}-coreutils-8.32"
11956 scheme@@(guix-user)> ,build grep
11957 $3 = "/gnu/store/@dots{}-grep-3.6"
11958 scheme@@(guix-user)> ,build (computed-file "x" #~(mkdir #$output))
11959 building /gnu/store/@dots{}-x.drv...
11960 $4 = "/gnu/store/@dots{}-x"
11961 scheme@@(guix-user)> ,use(ice-9 ftw)
11962 scheme@@(guix-user)> (scandir (string-append $3 "/bin"))
11963 $5 = ("." ".." "egrep" "fgrep" "grep")
11966 At a lower-level, a useful command is @code{lower}: it takes a file-like
11967 object and ``lowers'' it into a derivation (@pxref{Derivations}) or a
11971 scheme@@(guix-user)> ,lower grep
11972 $6 = #<derivation /gnu/store/@dots{}-grep-3.6.drv => /gnu/store/@dots{}-grep-3.6 7f0e639115f0>
11973 scheme@@(guix-user)> ,lower (plain-file "x" "Hello!")
11974 $7 = "/gnu/store/@dots{}-x"
11977 The full list of REPL commands can be seen by typing @code{,help guix}
11978 and is given below for reference.
11980 @deffn {REPL command} build @var{object}
11981 Lower @var{object} and build it if it's not already built, returning its
11982 output file name(s).
11985 @deffn {REPL command} lower @var{object}
11986 Lower @var{object} into a derivation or store file name and return it.
11989 @deffn {REPL command} verbosity @var{level}
11990 Change build verbosity to @var{level}.
11992 This is similar to the @option{--verbosity} command-line option
11993 (@pxref{Common Build Options}): level 0 means total silence, level 1
11994 shows build events only, and higher levels print build logs.
11997 @deffn {REPL command} run-in-store @var{exp}
11998 Run @var{exp}, a monadic expresssion, through the store monad.
11999 @xref{The Store Monad}, for more information.
12002 @deffn {REPL command} enter-store-monad
12003 Enter a new REPL to evaluate monadic expressions (@pxref{The Store
12004 Monad}). You can quit this ``inner'' REPL by typing @code{,q}.
12007 @c *********************************************************************
12011 This section describes Guix command-line utilities. Some of them are
12012 primarily targeted at developers and users who write new package
12013 definitions, while others are more generally useful. They complement
12014 the Scheme programming interface of Guix in a convenient way.
12017 * Invoking guix build:: Building packages from the command line.
12018 * Invoking guix edit:: Editing package definitions.
12019 * Invoking guix download:: Downloading a file and printing its hash.
12020 * Invoking guix hash:: Computing the cryptographic hash of a file.
12021 * Invoking guix import:: Importing package definitions.
12022 * Invoking guix refresh:: Updating package definitions.
12023 * Invoking guix style:: Styling package definitions.
12024 * Invoking guix lint:: Finding errors in package definitions.
12025 * Invoking guix size:: Profiling disk usage.
12026 * Invoking guix graph:: Visualizing the graph of packages.
12027 * Invoking guix publish:: Sharing substitutes.
12028 * Invoking guix challenge:: Challenging substitute servers.
12029 * Invoking guix copy:: Copying to and from a remote store.
12030 * Invoking guix container:: Process isolation.
12031 * Invoking guix weather:: Assessing substitute availability.
12032 * Invoking guix processes:: Listing client processes.
12035 @node Invoking guix build
12036 @section Invoking @command{guix build}
12038 @cindex package building
12039 @cindex @command{guix build}
12040 The @command{guix build} command builds packages or derivations and
12041 their dependencies, and prints the resulting store paths. Note that it
12042 does not modify the user's profile---this is the job of the
12043 @command{guix package} command (@pxref{Invoking guix package}). Thus,
12044 it is mainly useful for distribution developers.
12046 The general syntax is:
12049 guix build @var{options} @var{package-or-derivation}@dots{}
12052 As an example, the following command builds the latest versions of Emacs
12053 and of Guile, displays their build logs, and finally displays the
12054 resulting directories:
12057 guix build emacs guile
12060 Similarly, the following command builds all the available packages:
12063 guix build --quiet --keep-going \
12064 $(guix package -A | awk '@{ print $1 "@@" $2 @}')
12067 @var{package-or-derivation} may be either the name of a package found in
12068 the software distribution such as @code{coreutils} or
12069 @code{coreutils@@8.20}, or a derivation such as
12070 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
12071 package with the corresponding name (and optionally version) is searched
12072 for among the GNU distribution modules (@pxref{Package Modules}).
12074 Alternatively, the @option{--expression} option may be used to specify a
12075 Scheme expression that evaluates to a package; this is useful when
12076 disambiguating among several same-named packages or package variants is
12079 There may be zero or more @var{options}. The available options are
12080 described in the subsections below.
12083 * Common Build Options:: Build options for most commands.
12084 * Package Transformation Options:: Creating variants of packages.
12085 * Additional Build Options:: Options specific to 'guix build'.
12086 * Debugging Build Failures:: Real life packaging experience.
12089 @node Common Build Options
12090 @subsection Common Build Options
12092 A number of options that control the build process are common to
12093 @command{guix build} and other commands that can spawn builds, such as
12094 @command{guix package} or @command{guix archive}. These are the
12099 @item --load-path=@var{directory}
12100 @itemx -L @var{directory}
12101 Add @var{directory} to the front of the package module search path
12102 (@pxref{Package Modules}).
12104 This allows users to define their own packages and make them visible to
12105 the command-line tools.
12107 @item --keep-failed
12109 Keep the build tree of failed builds. Thus, if a build fails, its build
12110 tree is kept under @file{/tmp}, in a directory whose name is shown at
12111 the end of the build log. This is useful when debugging build issues.
12112 @xref{Debugging Build Failures}, for tips and tricks on how to debug
12115 This option implies @option{--no-offload}, and it has no effect when
12116 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
12117 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
12121 Keep going when some of the derivations fail to build; return only once
12122 all the builds have either completed or failed.
12124 The default behavior is to stop as soon as one of the specified
12125 derivations has failed.
12129 Do not build the derivations.
12131 @anchor{fallback-option}
12133 When substituting a pre-built binary fails, fall back to building
12134 packages locally (@pxref{Substitution Failure}).
12136 @item --substitute-urls=@var{urls}
12137 @anchor{client-substitute-urls}
12138 Consider @var{urls} the whitespace-separated list of substitute source
12139 URLs, overriding the default list of URLs of @command{guix-daemon}
12140 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
12142 This means that substitutes may be downloaded from @var{urls}, provided
12143 they are signed by a key authorized by the system administrator
12144 (@pxref{Substitutes}).
12146 When @var{urls} is the empty string, substitutes are effectively
12149 @item --no-substitutes
12150 Do not use substitutes for build products. That is, always build things
12151 locally instead of allowing downloads of pre-built binaries
12152 (@pxref{Substitutes}).
12155 Do not ``graft'' packages. In practice, this means that package updates
12156 available as grafts are not applied. @xref{Security Updates}, for more
12157 information on grafts.
12159 @item --rounds=@var{n}
12160 Build each derivation @var{n} times in a row, and raise an error if
12161 consecutive build results are not bit-for-bit identical.
12163 This is a useful way to detect non-deterministic builds processes.
12164 Non-deterministic build processes are a problem because they make it
12165 practically impossible for users to @emph{verify} whether third-party
12166 binaries are genuine. @xref{Invoking guix challenge}, for more.
12168 When used in conjunction with @option{--keep-failed}, the differing
12169 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12170 This makes it easy to look for differences between the two results.
12173 Do not use offload builds to other machines (@pxref{Daemon Offload
12174 Setup}). That is, always build things locally instead of offloading
12175 builds to remote machines.
12177 @item --max-silent-time=@var{seconds}
12178 When the build or substitution process remains silent for more than
12179 @var{seconds}, terminate it and report a build failure.
12181 By default, the daemon's setting is honored (@pxref{Invoking
12182 guix-daemon, @option{--max-silent-time}}).
12184 @item --timeout=@var{seconds}
12185 Likewise, when the build or substitution process lasts for more than
12186 @var{seconds}, terminate it and report a build failure.
12188 By default, the daemon's setting is honored (@pxref{Invoking
12189 guix-daemon, @option{--timeout}}).
12191 @c Note: This option is actually not part of %standard-build-options but
12192 @c most programs honor it.
12193 @cindex verbosity, of the command-line tools
12194 @cindex build logs, verbosity
12195 @item -v @var{level}
12196 @itemx --verbosity=@var{level}
12197 Use the given verbosity @var{level}, an integer. Choosing 0 means that
12198 no output is produced, 1 is for quiet output; 2 is similar to 1 but it
12199 additionally displays download URLs; 3 shows all the build log output on
12202 @item --cores=@var{n}
12204 Allow the use of up to @var{n} CPU cores for the build. The special
12205 value @code{0} means to use as many CPU cores as available.
12207 @item --max-jobs=@var{n}
12209 Allow at most @var{n} build jobs in parallel. @xref{Invoking
12210 guix-daemon, @option{--max-jobs}}, for details about this option and the
12211 equivalent @command{guix-daemon} option.
12213 @item --debug=@var{level}
12214 Produce debugging output coming from the build daemon. @var{level} must be an
12215 integer between 0 and 5; higher means more verbose output. Setting a level of
12216 4 or more may be helpful when debugging setup issues with the build daemon.
12220 Behind the scenes, @command{guix build} is essentially an interface to
12221 the @code{package-derivation} procedure of the @code{(guix packages)}
12222 module, and to the @code{build-derivations} procedure of the @code{(guix
12223 derivations)} module.
12225 In addition to options explicitly passed on the command line,
12226 @command{guix build} and other @command{guix} commands that support
12227 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
12229 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
12230 Users can define this variable to a list of command line options that
12231 will automatically be used by @command{guix build} and other
12232 @command{guix} commands that can perform builds, as in the example
12236 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
12239 These options are parsed independently, and the result is appended to
12240 the parsed command-line options.
12244 @node Package Transformation Options
12245 @subsection Package Transformation Options
12247 @cindex package variants
12248 Another set of command-line options supported by @command{guix build}
12249 and also @command{guix package} are @dfn{package transformation
12250 options}. These are options that make it possible to define @dfn{package
12251 variants}---for instance, packages built from different source code.
12252 This is a convenient way to create customized packages on the fly
12253 without having to type in the definitions of package variants
12254 (@pxref{Defining Packages}).
12256 Package transformation options are preserved across upgrades:
12257 @command{guix upgrade} attempts to apply transformation options
12258 initially used when creating the profile to the upgraded packages.
12260 The available options are listed below. Most commands support them and
12261 also support a @option{--help-transform} option that lists all the
12262 available options and a synopsis (these options are not shown in the
12263 @option{--help} output for brevity).
12267 @cindex performance, tuning code
12268 @cindex optimization, of package code
12269 @cindex tuning, of package code
12270 @cindex SIMD support
12271 @cindex tunable packages
12272 @cindex package multi-versioning
12273 @item --tune[=@var{cpu}]
12274 Use versions of the packages marked as ``tunable'' optimized for
12275 @var{cpu}. When @var{cpu} is @code{native}, or when it is omitted, tune
12276 for the CPU on which the @command{guix} command is running.
12278 Valid @var{cpu} names are those recognized by the underlying compiler,
12279 by default the GNU Compiler Collection. On x86_64 processors, this
12280 includes CPU names such as @code{nehalem}, @code{haswell}, and
12281 @code{skylake} (@pxref{x86 Options, @code{-march},, gcc, Using the GNU
12282 Compiler Collection (GCC)}).
12284 As new generations of CPUs come out, they augment the standard
12285 instruction set architecture (ISA) with additional instructions, in
12286 particular instructions for single-instruction/multiple-data (SIMD)
12287 parallel processing. For example, while Core2 and Skylake CPUs both
12288 implement the x86_64 ISA, only the latter supports AVX2 SIMD
12291 The primary gain one can expect from @option{--tune} is for programs
12292 that can make use of those SIMD capabilities @emph{and} that do not
12293 already have a mechanism to select the right optimized code at run time.
12294 Packages that have the @code{tunable?} property set are considered
12295 @dfn{tunable packages} by the @option{--tune} option; a package
12296 definition with the property set looks like this:
12300 (name "hello-simd")
12303 ;; This package may benefit from SIMD extensions so
12304 ;; mark it as "tunable".
12305 (properties '((tunable? . #t))))
12308 Other packages are not considered tunable. This allows Guix to use
12309 generic binaries in the cases where tuning for a specific CPU is
12310 unlikely to provide any gain.
12312 Tuned packages are built with @code{-march=@var{CPU}}; under the hood,
12313 the @option{-march} option is passed to the actual wrapper by a compiler
12314 wrapper. Since the build machine may not be able to run code for the
12315 target CPU micro-architecture, the test suite is not run when building a
12318 To reduce rebuilds to the minimum, tuned packages are @emph{grafted}
12319 onto packages that depend on them (@pxref{Security Updates, grafts}).
12320 Thus, using @option{--no-grafts} cancels the effect of @option{--tune}.
12322 We call this technique @dfn{package multi-versioning}: several variants
12323 of tunable packages may be built, one for each CPU variant. It is the
12324 coarse-grain counterpart of @dfn{function multi-versioning} as
12325 implemented by the GNU tool chain (@pxref{Function Multiversioning,,,
12326 gcc, Using the GNU Compiler Collection (GCC)}).
12328 @item --with-source=@var{source}
12329 @itemx --with-source=@var{package}=@var{source}
12330 @itemx --with-source=@var{package}@@@var{version}=@var{source}
12331 Use @var{source} as the source of @var{package}, and @var{version} as
12332 its version number.
12333 @var{source} must be a file name or a URL, as for @command{guix
12334 download} (@pxref{Invoking guix download}).
12336 When @var{package} is omitted,
12337 it is taken to be the package name specified on the
12338 command line that matches the base of @var{source}---e.g.,
12339 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
12340 package is @code{guile}.
12342 Likewise, when @var{version} is omitted, the version string is inferred from
12343 @var{source}; in the previous example, it is @code{2.0.10}.
12345 This option allows users to try out versions of packages other than the
12346 one provided by the distribution. The example below downloads
12347 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
12348 the @code{ed} package:
12351 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
12354 As a developer, @option{--with-source} makes it easy to test release
12358 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
12361 @dots{} or to build from a checkout in a pristine environment:
12364 $ git clone git://git.sv.gnu.org/guix.git
12365 $ guix build guix --with-source=guix@@1.0=./guix
12368 @item --with-input=@var{package}=@var{replacement}
12369 Replace dependency on @var{package} by a dependency on
12370 @var{replacement}. @var{package} must be a package name, and
12371 @var{replacement} must be a package specification such as @code{guile}
12372 or @code{guile@@1.8}.
12374 For instance, the following command builds Guix, but replaces its
12375 dependency on the current stable version of Guile with a dependency on
12376 the legacy version of Guile, @code{guile@@2.0}:
12379 guix build --with-input=guile=guile@@2.0 guix
12382 This is a recursive, deep replacement. So in this example, both
12383 @code{guix} and its dependency @code{guile-json} (which also depends on
12384 @code{guile}) get rebuilt against @code{guile@@2.0}.
12386 This is implemented using the @code{package-input-rewriting} Scheme
12387 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
12389 @item --with-graft=@var{package}=@var{replacement}
12390 This is similar to @option{--with-input} but with an important difference:
12391 instead of rebuilding the whole dependency chain, @var{replacement} is
12392 built and then @dfn{grafted} onto the binaries that were initially
12393 referring to @var{package}. @xref{Security Updates}, for more
12394 information on grafts.
12396 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
12397 and all its dependencies, replacing references to the version of GnuTLS
12398 they currently refer to:
12401 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
12404 This has the advantage of being much faster than rebuilding everything.
12405 But there is a caveat: it works if and only if @var{package} and
12406 @var{replacement} are strictly compatible---for example, if they provide
12407 a library, the application binary interface (ABI) of those libraries
12408 must be compatible. If @var{replacement} is somehow incompatible with
12409 @var{package}, then the resulting package may be unusable. Use with
12412 @cindex debugging info, rebuilding
12413 @item --with-debug-info=@var{package}
12414 Build @var{package} in a way that preserves its debugging info and graft
12415 it onto packages that depend on it. This is useful if @var{package}
12416 does not already provide debugging info as a @code{debug} output
12417 (@pxref{Installing Debugging Files}).
12419 For example, suppose you're experiencing a crash in Inkscape and would
12420 like to see what's up in GLib, a library deep down in Inkscape's
12421 dependency graph. GLib lacks a @code{debug} output, so debugging is
12422 tough. Fortunately, you rebuild GLib with debugging info and tack it on
12426 guix install inkscape --with-debug-info=glib
12429 Only GLib needs to be recompiled so this takes a reasonable amount of
12430 time. @xref{Installing Debugging Files}, for more info.
12433 Under the hood, this option works by passing the @samp{#:strip-binaries?
12434 #f} to the build system of the package of interest (@pxref{Build
12435 Systems}). Most build systems support that option but some do not. In
12436 that case, an error is raised.
12438 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
12439 the case), debugging info will remain unavailable even when
12440 @code{#:strip-binaries?} is false.
12443 @cindex tool chain, changing the build tool chain of a package
12444 @item --with-c-toolchain=@var{package}=@var{toolchain}
12445 This option changes the compilation of @var{package} and everything that
12446 depends on it so that they get built with @var{toolchain} instead of the
12447 default GNU tool chain for C/C++.
12449 Consider this example:
12452 guix build octave-cli \
12453 --with-c-toolchain=fftw=gcc-toolchain@@10 \
12454 --with-c-toolchain=fftwf=gcc-toolchain@@10
12457 The command above builds a variant of the @code{fftw} and @code{fftwf}
12458 packages using version 10 of @code{gcc-toolchain} instead of the default
12459 tool chain, and then builds a variant of the GNU@tie{}Octave
12460 command-line interface using them. GNU@tie{}Octave itself is also built
12461 with @code{gcc-toolchain@@10}.
12463 This other example builds the Hardware Locality (@code{hwloc}) library
12464 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
12468 guix build --with-c-toolchain=hwloc=clang-toolchain \
12469 intel-mpi-benchmarks
12473 There can be application binary interface (ABI) incompatibilities among
12474 tool chains. This is particularly true of the C++ standard library and
12475 run-time support libraries such as that of OpenMP@. By rebuilding all
12476 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
12477 the risks of incompatibility but cannot entirely eliminate them. Choose
12478 @var{package} wisely.
12481 @item --with-git-url=@var{package}=@var{url}
12482 @cindex Git, using the latest commit
12483 @cindex latest commit, building
12484 Build @var{package} from the latest commit of the @code{master} branch of the
12485 Git repository at @var{url}. Git sub-modules of the repository are fetched,
12488 For example, the following command builds the NumPy Python library against the
12489 latest commit of the master branch of Python itself:
12492 guix build python-numpy \
12493 --with-git-url=python=https://github.com/python/cpython
12496 This option can also be combined with @option{--with-branch} or
12497 @option{--with-commit} (see below).
12499 @cindex continuous integration
12500 Obviously, since it uses the latest commit of the given branch, the result of
12501 such a command varies over time. Nevertheless it is a convenient way to
12502 rebuild entire software stacks against the latest commit of one or more
12503 packages. This is particularly useful in the context of continuous
12506 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
12507 consecutive accesses to the same repository. You may want to clean it up once
12508 in a while to save disk space.
12510 @item --with-branch=@var{package}=@var{branch}
12511 Build @var{package} from the latest commit of @var{branch}. If the
12512 @code{source} field of @var{package} is an origin with the @code{git-fetch}
12513 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
12514 repository URL is taken from that @code{source}. Otherwise you have to use
12515 @option{--with-git-url} to specify the URL of the Git repository.
12517 For instance, the following command builds @code{guile-sqlite3} from the
12518 latest commit of its @code{master} branch, and then builds @code{guix} (which
12519 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
12520 specific @code{guile-sqlite3} build:
12523 guix build --with-branch=guile-sqlite3=master cuirass
12526 @item --with-commit=@var{package}=@var{commit}
12527 This is similar to @option{--with-branch}, except that it builds from
12528 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
12529 Git commit SHA1 identifier, a tag, or a @command{git describe} style
12530 identifier such as @code{1.0-3-gabc123}.
12532 @item --with-patch=@var{package}=@var{file}
12533 Add @var{file} to the list of patches applied to @var{package}, where
12534 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
12535 @var{file} must contain a patch; it is applied with the flags specified
12536 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
12537 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
12538 Comparing and Merging Files}).
12540 As an example, the command below rebuilds Coreutils with the GNU C
12541 Library (glibc) patched with the given patch:
12544 guix build coreutils --with-patch=glibc=./glibc-frob.patch
12547 In this example, glibc itself as well as everything that leads to
12548 Coreutils in the dependency graph is rebuilt.
12550 @cindex upstream, latest version
12551 @item --with-latest=@var{package}
12552 So you like living on the bleeding edge? This option is for you! It
12553 replaces occurrences of @var{package} in the dependency graph with its
12554 latest upstream version, as reported by @command{guix refresh}
12555 (@pxref{Invoking guix refresh}).
12557 It does so by determining the latest upstream release of @var{package}
12558 (if possible), downloading it, and authenticating it @emph{if} it comes
12559 with an OpenPGP signature.
12561 As an example, the command below builds Guix against the latest version
12565 guix build guix --with-latest=guile-json
12568 There are limitations. First, in cases where the tool cannot or does
12569 not know how to authenticate source code, you are at risk of running
12570 malicious code; a warning is emitted in this case. Second, this option
12571 simply changes the source used in the existing package definitions,
12572 which is not always sufficient: there might be additional dependencies
12573 that need to be added, patches to apply, and more generally the quality
12574 assurance work that Guix developers normally do will be missing.
12576 You've been warned! In all the other cases, it's a snappy way to stay
12577 on top. We encourage you to submit patches updating the actual package
12578 definitions once you have successfully tested an upgrade
12579 (@pxref{Contributing}).
12581 @cindex test suite, skipping
12582 @item --without-tests=@var{package}
12583 Build @var{package} without running its tests. This can be useful in
12584 situations where you want to skip the lengthy test suite of a
12585 intermediate package, or if a package's test suite fails in a
12586 non-deterministic fashion. It should be used with care because running
12587 the test suite is a good way to ensure a package is working as intended.
12589 Turning off tests leads to a different store item. Consequently, when
12590 using this option, anything that depends on @var{package} must be
12591 rebuilt, as in this example:
12594 guix install --without-tests=python python-notebook
12597 The command above installs @code{python-notebook} on top of
12598 @code{python} built without running its test suite. To do so, it also
12599 rebuilds everything that depends on @code{python}, including
12600 @code{python-notebook} itself.
12602 Internally, @option{--without-tests} relies on changing the
12603 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
12604 Systems}). Note that some packages use a customized @code{check} phase
12605 that does not respect a @code{#:tests? #f} setting. Therefore,
12606 @option{--without-tests} has no effect on these packages.
12610 Wondering how to achieve the same effect using Scheme code, for example
12611 in your manifest, or how to write your own package transformation?
12612 @xref{Defining Package Variants}, for an overview of the programming
12613 interfaces available.
12615 @node Additional Build Options
12616 @subsection Additional Build Options
12618 The command-line options presented below are specific to @command{guix
12625 Build quietly, without displaying the build log; this is equivalent to
12626 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
12627 (or similar) and can always be retrieved using the @option{--log-file} option.
12629 @item --file=@var{file}
12630 @itemx -f @var{file}
12631 Build the package, derivation, or other file-like object that the code within
12632 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
12634 As an example, @var{file} might contain a package definition like this
12635 (@pxref{Defining Packages}):
12638 @include package-hello.scm
12641 The @var{file} may also contain a JSON representation of one or more
12642 package definitions. Running @code{guix build -f} on @file{hello.json}
12643 with the following contents would result in building the packages
12644 @code{myhello} and @code{greeter}:
12647 @verbatiminclude package-hello.json
12650 @item --manifest=@var{manifest}
12651 @itemx -m @var{manifest}
12652 Build all packages listed in the given @var{manifest}
12653 (@pxref{profile-manifest, @option{--manifest}}).
12655 @item --expression=@var{expr}
12656 @itemx -e @var{expr}
12657 Build the package or derivation @var{expr} evaluates to.
12659 For example, @var{expr} may be @code{(@@ (gnu packages guile)
12660 guile-1.8)}, which unambiguously designates this specific variant of
12661 version 1.8 of Guile.
12663 Alternatively, @var{expr} may be a G-expression, in which case it is used
12664 as a build program passed to @code{gexp->derivation}
12665 (@pxref{G-Expressions}).
12667 Lastly, @var{expr} may refer to a zero-argument monadic procedure
12668 (@pxref{The Store Monad}). The procedure must return a derivation as a
12669 monadic value, which is then passed through @code{run-with-store}.
12673 Build the source derivations of the packages, rather than the packages
12676 For instance, @code{guix build -S gcc} returns something like
12677 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
12680 The returned source tarball is the result of applying any patches and
12681 code snippets specified in the package @code{origin} (@pxref{Defining
12684 @cindex source, verification
12685 As with other derivations, the result of building a source derivation
12686 can be verified using the @option{--check} option (@pxref{build-check}).
12687 This is useful to validate that a (potentially already built or
12688 substituted, thus cached) package source matches against its declared
12691 Note that @command{guix build -S} compiles the sources only of the
12692 specified packages. They do not include the sources of statically
12693 linked dependencies and by themselves are insufficient for reproducing
12697 Fetch and return the source of @var{package-or-derivation} and all their
12698 dependencies, recursively. This is a handy way to obtain a local copy
12699 of all the source code needed to build @var{packages}, allowing you to
12700 eventually build them even without network access. It is an extension
12701 of the @option{--source} option and can accept one of the following
12702 optional argument values:
12706 This value causes the @option{--sources} option to behave in the same way
12707 as the @option{--source} option.
12710 Build the source derivations of all packages, including any source that
12711 might be listed as @code{inputs}. This is the default value.
12714 $ guix build --sources tzdata
12715 The following derivations will be built:
12716 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
12717 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12721 Build the source derivations of all packages, as well of all transitive
12722 inputs to the packages. This can be used e.g.@: to
12723 prefetch package source for later offline building.
12726 $ guix build --sources=transitive tzdata
12727 The following derivations will be built:
12728 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12729 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
12730 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
12731 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
12732 /gnu/store/@dots{}-make-4.1.tar.xz.drv
12733 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
12739 @item --system=@var{system}
12740 @itemx -s @var{system}
12741 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
12742 the system type of the build host. The @command{guix build} command allows
12743 you to repeat this option several times, in which case it builds for all the
12744 specified systems; other commands ignore extraneous @option{-s} options.
12747 The @option{--system} flag is for @emph{native} compilation and must not
12748 be confused with cross-compilation. See @option{--target} below for
12749 information on cross-compilation.
12752 An example use of this is on Linux-based systems, which can emulate
12753 different personalities. For instance, passing
12754 @option{--system=i686-linux} on an @code{x86_64-linux} system or
12755 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
12756 you to build packages in a complete 32-bit environment.
12759 Building for an @code{armhf-linux} system is unconditionally enabled on
12760 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
12761 allow for this functionality, notably the ThunderX.
12764 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
12765 is enabled (@pxref{Virtualization Services,
12766 @code{qemu-binfmt-service-type}}), you can build for any system for
12767 which a QEMU @code{binfmt_misc} handler is installed.
12769 Builds for a system other than that of the machine you are using can
12770 also be offloaded to a remote machine of the right architecture.
12771 @xref{Daemon Offload Setup}, for more information on offloading.
12773 @item --target=@var{triplet}
12774 @cindex cross-compilation
12775 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
12776 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
12777 configuration triplets,, autoconf, Autoconf}).
12779 @item --list-systems
12780 List all the supported systems, that can be passed as an argument to
12783 @item --list-targets
12784 List all the supported targets, that can be passed as an argument to
12787 @anchor{build-check}
12789 @cindex determinism, checking
12790 @cindex reproducibility, checking
12791 Rebuild @var{package-or-derivation}, which are already available in the
12792 store, and raise an error if the build results are not bit-for-bit
12795 This mechanism allows you to check whether previously installed
12796 substitutes are genuine (@pxref{Substitutes}), or whether the build result
12797 of a package is deterministic. @xref{Invoking guix challenge}, for more
12798 background information and tools.
12800 When used in conjunction with @option{--keep-failed}, the differing
12801 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12802 This makes it easy to look for differences between the two results.
12805 @cindex repairing store items
12806 @cindex corruption, recovering from
12807 Attempt to repair the specified store items, if they are corrupt, by
12808 re-downloading or rebuilding them.
12810 This operation is not atomic and thus restricted to @code{root}.
12812 @item --derivations
12814 Return the derivation paths, not the output paths, of the given
12817 @item --root=@var{file}
12818 @itemx -r @var{file}
12819 @cindex GC roots, adding
12820 @cindex garbage collector roots, adding
12821 Make @var{file} a symlink to the result, and register it as a garbage
12824 Consequently, the results of this @command{guix build} invocation are
12825 protected from garbage collection until @var{file} is removed. When
12826 that option is omitted, build results are eligible for garbage
12827 collection as soon as the build completes. @xref{Invoking guix gc}, for
12831 @cindex build logs, access
12832 Return the build log file names or URLs for the given
12833 @var{package-or-derivation}, or raise an error if build logs are
12836 This works regardless of how packages or derivations are specified. For
12837 instance, the following invocations are equivalent:
12840 guix build --log-file $(guix build -d guile)
12841 guix build --log-file $(guix build guile)
12842 guix build --log-file guile
12843 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
12846 If a log is unavailable locally, and unless @option{--no-substitutes} is
12847 passed, the command looks for a corresponding log on one of the
12848 substitute servers (as specified with @option{--substitute-urls}).
12850 So for instance, imagine you want to see the build log of GDB on
12851 @code{aarch64}, but you are actually on an @code{x86_64} machine:
12854 $ guix build --log-file gdb -s aarch64-linux
12855 https://@value{SUBSTITUTE-SERVER-1}/log/@dots{}-gdb-7.10
12858 You can freely access a huge library of build logs!
12861 @node Debugging Build Failures
12862 @subsection Debugging Build Failures
12864 @cindex build failures, debugging
12865 When defining a new package (@pxref{Defining Packages}), you will
12866 probably find yourself spending some time debugging and tweaking the
12867 build until it succeeds. To do that, you need to operate the build
12868 commands yourself in an environment as close as possible to the one the
12871 To that end, the first thing to do is to use the @option{--keep-failed}
12872 or @option{-K} option of @command{guix build}, which will keep the
12873 failed build tree in @file{/tmp} or whatever directory you specified as
12874 @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
12876 From there on, you can @command{cd} to the failed build tree and source
12877 the @file{environment-variables} file, which contains all the
12878 environment variable definitions that were in place when the build
12879 failed. So let's say you're debugging a build failure in package
12880 @code{foo}; a typical session would look like this:
12883 $ guix build foo -K
12884 @dots{} @i{build fails}
12885 $ cd /tmp/guix-build-foo.drv-0
12886 $ source ./environment-variables
12890 Now, you can invoke commands as if you were the daemon (almost) and
12891 troubleshoot your build process.
12893 Sometimes it happens that, for example, a package's tests pass when you
12894 run them manually but they fail when the daemon runs them. This can
12895 happen because the daemon runs builds in containers where, unlike in our
12896 environment above, network access is missing, @file{/bin/sh} does not
12897 exist, etc. (@pxref{Build Environment Setup}).
12899 In such cases, you may need to run inspect the build process from within
12900 a container similar to the one the build daemon creates:
12903 $ guix build -K foo
12905 $ cd /tmp/guix-build-foo.drv-0
12906 $ guix shell --no-grafts -C -D foo strace gdb
12907 [env]# source ./environment-variables
12911 Here, @command{guix shell -C} creates a container and spawns a new
12912 shell in it (@pxref{Invoking guix shell}). The @command{strace gdb}
12913 part adds the @command{strace} and @command{gdb} commands to
12914 the container, which you may find handy while debugging. The
12915 @option{--no-grafts} option makes sure we get the exact same
12916 environment, with ungrafted packages (@pxref{Security Updates}, for more
12919 To get closer to a container like that used by the build daemon, we can
12920 remove @file{/bin/sh}:
12926 (Don't worry, this is harmless: this is all happening in the throw-away
12927 container created by @command{guix shell}.)
12929 The @command{strace} command is probably not in the search path, but we
12933 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
12936 In this way, not only you will have reproduced the environment variables
12937 the daemon uses, you will also be running the build process in a container
12938 similar to the one the daemon uses.
12941 @node Invoking guix edit
12942 @section Invoking @command{guix edit}
12944 @cindex @command{guix edit}
12945 @cindex package definition, editing
12946 So many packages, so many source files! The @command{guix edit} command
12947 facilitates the life of users and packagers by pointing their editor at
12948 the source file containing the definition of the specified packages.
12952 guix edit gcc@@4.9 vim
12956 launches the program specified in the @env{VISUAL} or in the
12957 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
12960 If you are using a Guix Git checkout (@pxref{Building from Git}), or
12961 have created your own packages on @env{GUIX_PACKAGE_PATH}
12962 (@pxref{Package Modules}), you will be able to edit the package
12963 recipes. In other cases, you will be able to examine the read-only recipes
12964 for packages currently in the store.
12966 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
12967 @option{--load-path=@var{directory}} (or in short @option{-L
12968 @var{directory}}) allows you to add @var{directory} to the front of the
12969 package module search path and so make your own packages visible.
12971 @node Invoking guix download
12972 @section Invoking @command{guix download}
12974 @cindex @command{guix download}
12975 @cindex downloading package sources
12976 When writing a package definition, developers typically need to download
12977 a source tarball, compute its SHA256 hash, and write that
12978 hash in the package definition (@pxref{Defining Packages}). The
12979 @command{guix download} tool helps with this task: it downloads a file
12980 from the given URI, adds it to the store, and prints both its file name
12981 in the store and its SHA256 hash.
12983 The fact that the downloaded file is added to the store saves bandwidth:
12984 when the developer eventually tries to build the newly defined package
12985 with @command{guix build}, the source tarball will not have to be
12986 downloaded again because it is already in the store. It is also a
12987 convenient way to temporarily stash files, which may be deleted
12988 eventually (@pxref{Invoking guix gc}).
12990 The @command{guix download} command supports the same URIs as used in
12991 package definitions. In particular, it supports @code{mirror://} URIs.
12992 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
12993 Guile bindings for GnuTLS are available in the user's environment; when
12994 they are not available, an error is raised. @xref{Guile Preparations,
12995 how to install the GnuTLS bindings for Guile,, gnutls-guile,
12996 GnuTLS-Guile}, for more information.
12998 @command{guix download} verifies HTTPS server certificates by loading
12999 the certificates of X.509 authorities from the directory pointed to by
13000 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
13001 Certificates}), unless @option{--no-check-certificate} is used.
13003 The following options are available:
13006 @item --hash=@var{algorithm}
13007 @itemx -H @var{algorithm}
13008 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
13009 hash}, for more information.
13011 @item --format=@var{fmt}
13012 @itemx -f @var{fmt}
13013 Write the hash in the format specified by @var{fmt}. For more
13014 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
13016 @item --no-check-certificate
13017 Do not validate the X.509 certificates of HTTPS servers.
13019 When using this option, you have @emph{absolutely no guarantee} that you
13020 are communicating with the authentic server responsible for the given
13021 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
13023 @item --output=@var{file}
13024 @itemx -o @var{file}
13025 Save the downloaded file to @var{file} instead of adding it to the
13029 @node Invoking guix hash
13030 @section Invoking @command{guix hash}
13032 @cindex @command{guix hash}
13033 The @command{guix hash} command computes the hash of a file.
13034 It is primarily a convenience tool for anyone contributing to the
13035 distribution: it computes the cryptographic hash of one or more files, which can be
13036 used in the definition of a package (@pxref{Defining Packages}).
13038 The general syntax is:
13041 guix hash @var{option} @var{file} ...
13044 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
13045 hash of data read from standard input. @command{guix hash} has the
13050 @item --hash=@var{algorithm}
13051 @itemx -H @var{algorithm}
13052 Compute a hash using the specified @var{algorithm}, @code{sha256} by
13055 @var{algorithm} must be the name of a cryptographic hash algorithm
13056 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
13057 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
13058 Reference Manual}).
13060 @item --format=@var{fmt}
13061 @itemx -f @var{fmt}
13062 Write the hash in the format specified by @var{fmt}.
13064 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
13065 (@code{hex} and @code{hexadecimal} can be used as well).
13067 If the @option{--format} option is not specified, @command{guix hash}
13068 will output the hash in @code{nix-base32}. This representation is used
13069 in the definitions of packages.
13073 The @option{--recursive} option is deprecated in favor of
13074 @option{--serializer=nar} (see below); @option{-r} remains accepted as a
13075 convenient shorthand.
13077 @item --serializer=@var{type}
13078 @itemx -S @var{type}
13079 Compute the hash on @var{file} using @var{type} serialization.
13081 @var{type} may be one of the following:
13085 This is the default: it computes the hash of a file's contents.
13088 Compute the hash of a ``normalized archive'' (or ``nar'') containing
13089 @var{file}, including its children if it is a directory. Some of the
13090 metadata of @var{file} is part of the archive; for instance, when
13091 @var{file} is a regular file, the hash is different depending on whether
13092 @var{file} is executable or not. Metadata such as time stamps have no
13093 impact on the hash (@pxref{Invoking guix archive}, for more info on the
13095 @c FIXME: Replace xref above with xref to an ``Archive'' section when
13099 Compute the hash of the file or directory as a Git ``tree'', following
13100 the same method as the Git version control system.
13103 @item --exclude-vcs
13105 When combined with @option{--recursive}, exclude version control system
13106 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
13109 As an example, here is how you would compute the hash of a Git checkout,
13110 which is useful when using the @code{git-fetch} method (@pxref{origin
13114 $ git clone http://example.org/foo.git
13116 $ guix hash -x --serializer=nar .
13120 @node Invoking guix import
13121 @section Invoking @command{guix import}
13123 @cindex importing packages
13124 @cindex package import
13125 @cindex package conversion
13126 @cindex Invoking @command{guix import}
13127 The @command{guix import} command is useful for people who would like to
13128 add a package to the distribution with as little work as
13129 possible---a legitimate demand. The command knows of a few
13130 repositories from which it can ``import'' package metadata. The result
13131 is a package definition, or a template thereof, in the format we know
13132 (@pxref{Defining Packages}).
13134 The general syntax is:
13137 guix import @var{importer} @var{options}@dots{}
13140 @var{importer} specifies the source from which to import package
13141 metadata, and @var{options} specifies a package identifier and other
13142 options specific to @var{importer}.
13144 Some of the importers rely on the ability to run the @command{gpgv} command.
13145 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
13148 Currently, the available ``importers'' are:
13152 Import metadata for the given GNU package. This provides a template
13153 for the latest version of that GNU package, including the hash of its
13154 source tarball, and its canonical synopsis and description.
13156 Additional information such as the package dependencies and its
13157 license needs to be figured out manually.
13159 For example, the following command returns a package definition for
13163 guix import gnu hello
13166 Specific command-line options are:
13169 @item --key-download=@var{policy}
13170 As for @command{guix refresh}, specify the policy to handle missing
13171 OpenPGP keys when verifying the package signature. @xref{Invoking guix
13172 refresh, @option{--key-download}}.
13177 Import metadata from the @uref{https://pypi.python.org/, Python Package
13178 Index}. Information is taken from the JSON-formatted description
13179 available at @code{pypi.python.org} and usually includes all the relevant
13180 information, including package dependencies. For maximum efficiency, it
13181 is recommended to install the @command{unzip} utility, so that the
13182 importer can unzip Python wheels and gather data from them.
13184 The command below imports metadata for the latest version of the
13185 @code{itsdangerous} Python package:
13188 guix import pypi itsdangerous
13191 You can also ask for a specific version:
13194 guix import pypi itsdangerous@@1.1.0
13200 Traverse the dependency graph of the given upstream package recursively
13201 and generate package expressions for all those packages that are not yet
13207 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
13208 is taken from the JSON-formatted description available at
13209 @code{rubygems.org} and includes most relevant information, including
13210 runtime dependencies. There are some caveats, however. The metadata
13211 doesn't distinguish between synopses and descriptions, so the same string
13212 is used for both fields. Additionally, the details of non-Ruby
13213 dependencies required to build native extensions is unavailable and left
13214 as an exercise to the packager.
13216 The command below imports metadata for the @code{rails} Ruby package:
13219 guix import gem rails
13225 Traverse the dependency graph of the given upstream package recursively
13226 and generate package expressions for all those packages that are not yet
13233 Import metadata from @uref{https://content.minetest.net, ContentDB}.
13234 Information is taken from the JSON-formatted metadata provided through
13235 @uref{https://content.minetest.net/help/api/, ContentDB's API} and
13236 includes most relevant information, including dependencies. There are
13237 some caveats, however. The license information is often incomplete.
13238 The commit hash is sometimes missing. The descriptions are in the
13239 Markdown format, but Guix uses Texinfo instead. Texture packs and
13240 subgames are unsupported.
13242 The command below imports metadata for the Mesecons mod by Jeija:
13245 guix import minetest Jeija/mesecons
13248 The author name can also be left out:
13251 guix import minetest mesecons
13257 Traverse the dependency graph of the given upstream package recursively
13258 and generate package expressions for all those packages that are not yet
13264 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
13265 Information is taken from the JSON-formatted metadata provided through
13266 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
13267 relevant information, such as module dependencies. License information
13268 should be checked closely. If Perl is available in the store, then the
13269 @code{corelist} utility will be used to filter core modules out of the
13270 list of dependencies.
13272 The command command below imports metadata for the Acme::Boolean Perl
13276 guix import cpan Acme::Boolean
13281 @cindex Bioconductor
13282 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
13283 central repository for the @uref{https://r-project.org, GNU@tie{}R
13284 statistical and graphical environment}.
13286 Information is extracted from the @file{DESCRIPTION} file of the package.
13288 The command command below imports metadata for the Cairo R package:
13291 guix import cran Cairo
13294 You can also ask for a specific version:
13297 guix import cran rasterVis@@0.50.3
13300 When @option{--recursive} is added, the importer will traverse the
13301 dependency graph of the given upstream package recursively and generate
13302 package expressions for all those packages that are not yet in Guix.
13304 When @option{--style=specification} is added, the importer will generate
13305 package definitions whose inputs are package specifications instead of
13306 references to package variables. This is useful when generated package
13307 definitions are to be appended to existing user modules, as the list of
13308 used package modules need not be changed. The default is
13309 @option{--style=variable}.
13311 When @option{--archive=bioconductor} is added, metadata is imported from
13312 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
13313 packages for the analysis and comprehension of high-throughput
13314 genomic data in bioinformatics.
13316 Information is extracted from the @file{DESCRIPTION} file contained in the
13319 The command below imports metadata for the GenomicRanges R package:
13322 guix import cran --archive=bioconductor GenomicRanges
13325 Finally, you can also import R packages that have not yet been published on
13326 CRAN or Bioconductor as long as they are in a git repository. Use
13327 @option{--archive=git} followed by the URL of the git repository:
13330 guix import cran --archive=git https://github.com/immunogenomics/harmony
13336 Import TeX package information from the TeX Live package database for
13337 TeX packages that are part of the @uref{https://www.tug.org/texlive/,
13338 TeX Live distribution}.
13340 Information about the package is obtained from the TeX Live package
13341 database, a plain text file that is included in the @code{texlive-bin}
13342 package. The source code is downloaded from possibly multiple locations
13343 in the SVN repository of the Tex Live project.
13345 The command command below imports metadata for the @code{fontspec}
13349 guix import texlive fontspec
13353 @cindex JSON, import
13354 Import package metadata from a local JSON file. Consider the following
13355 example package definition in JSON format:
13361 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
13362 "build-system": "gnu",
13363 "home-page": "https://www.gnu.org/software/hello/",
13364 "synopsis": "Hello, GNU world: An example GNU package",
13365 "description": "GNU Hello prints a greeting.",
13366 "license": "GPL-3.0+",
13367 "native-inputs": ["gettext"]
13371 The field names are the same as for the @code{<package>} record
13372 (@xref{Defining Packages}). References to other packages are provided
13373 as JSON lists of quoted package specification strings such as
13374 @code{guile} or @code{guile@@2.0}.
13376 The importer also supports a more explicit source definition using the
13377 common fields for @code{<origin>} records:
13383 "method": "url-fetch",
13384 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
13386 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
13393 The command below reads metadata from the JSON file @code{hello.json}
13394 and outputs a package expression:
13397 guix import json hello.json
13402 Import metadata from the Haskell community's central package archive
13403 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
13404 Cabal files and includes all the relevant information, including package
13407 Specific command-line options are:
13412 Read a Cabal file from standard input.
13413 @item --no-test-dependencies
13415 Do not include dependencies required only by the test suites.
13416 @item --cabal-environment=@var{alist}
13417 @itemx -e @var{alist}
13418 @var{alist} is a Scheme alist defining the environment in which the
13419 Cabal conditionals are evaluated. The accepted keys are: @code{os},
13420 @code{arch}, @code{impl} and a string representing the name of a flag.
13421 The value associated with a flag has to be either the symbol
13422 @code{true} or @code{false}. The value associated with other keys
13423 has to conform to the Cabal file format definition. The default value
13424 associated with the keys @code{os}, @code{arch} and @code{impl} is
13425 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
13428 Traverse the dependency graph of the given upstream package recursively
13429 and generate package expressions for all those packages that are not yet
13433 The command below imports metadata for the latest version of the
13434 HTTP Haskell package without including test dependencies and
13435 specifying the value of the flag @samp{network-uri} as @code{false}:
13438 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
13441 A specific package version may optionally be specified by following the
13442 package name by an at-sign and a version number as in the following example:
13445 guix import hackage mtl@@2.1.3.1
13450 The @code{stackage} importer is a wrapper around the @code{hackage} one.
13451 It takes a package name, looks up the package version included in a
13452 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
13453 release and uses the @code{hackage} importer to retrieve its metadata.
13454 Note that it is up to you to select an LTS release compatible with the
13455 GHC compiler used by Guix.
13457 Specific command-line options are:
13460 @item --no-test-dependencies
13462 Do not include dependencies required only by the test suites.
13463 @item --lts-version=@var{version}
13464 @itemx -l @var{version}
13465 @var{version} is the desired LTS release version. If omitted the latest
13469 Traverse the dependency graph of the given upstream package recursively
13470 and generate package expressions for all those packages that are not yet
13474 The command below imports metadata for the HTTP Haskell package
13475 included in the LTS Stackage release version 7.18:
13478 guix import stackage --lts-version=7.18 HTTP
13483 Import metadata from an Emacs Lisp Package Archive (ELPA) package
13484 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
13486 Specific command-line options are:
13489 @item --archive=@var{repo}
13490 @itemx -a @var{repo}
13491 @var{repo} identifies the archive repository from which to retrieve the
13492 information. Currently the supported repositories and their identifiers
13496 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
13497 identifier. This is the default.
13499 Packages from @code{elpa.gnu.org} are signed with one of the keys
13500 contained in the GnuPG keyring at
13501 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
13502 @code{emacs} package (@pxref{Package Installation, ELPA package
13503 signatures,, emacs, The GNU Emacs Manual}).
13506 @uref{https://elpa.nongnu.org/nongnu/, NonGNU}, selected by the
13507 @code{nongnu} identifier.
13510 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
13511 @code{melpa-stable} identifier.
13514 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
13520 Traverse the dependency graph of the given upstream package recursively
13521 and generate package expressions for all those packages that are not yet
13527 Import metadata from the crates.io Rust package repository
13528 @uref{https://crates.io, crates.io}, as in this example:
13531 guix import crate blake2-rfc
13534 The crate importer also allows you to specify a version string:
13537 guix import crate constant-time-eq@@0.1.0
13540 Additional options include:
13545 Traverse the dependency graph of the given upstream package recursively
13546 and generate package expressions for all those packages that are not yet
13552 Import metadata from the Elm package repository
13553 @uref{https://package.elm-lang.org, package.elm-lang.org}, as in this example:
13556 guix import elm elm-explorations/webgl
13559 The Elm importer also allows you to specify a version string:
13562 guix import elm elm-explorations/webgl@@1.1.3
13565 Additional options include:
13570 Traverse the dependency graph of the given upstream package recursively
13571 and generate package expressions for all those packages that are not yet
13578 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
13579 repository used by the OCaml community.
13581 Additional options include:
13586 Traverse the dependency graph of the given upstream package recursively
13587 and generate package expressions for all those packages that are not yet
13590 By default, packages are searched in the official OPAM repository. This
13591 option, which can be used more than once, lets you add other repositories
13592 which will be searched for packages. It accepts as valid arguments:
13595 @item the name of a known repository - can be one of @code{opam},
13596 @code{coq} (equivalent to @code{coq-released}),
13597 @code{coq-core-dev}, @code{coq-extra-dev} or @code{grew}.
13598 @item the URL of a repository as expected by the
13599 @code{opam repository add} command (for instance, the URL equivalent
13600 of the above @code{opam} name would be
13601 @uref{https://opam.ocaml.org}).
13602 @item the path to a local copy of a repository (a directory containing a
13603 @file{packages/} sub-directory).
13606 Repositories are assumed to be passed to this option by order of
13607 preference. The additional repositories will not replace the default
13608 @code{opam} repository, which is always kept as a fallback.
13610 Also, please note that versions are not compared across repositories.
13611 The first repository (from left to right) that has at least one version
13612 of a given package will prevail over any others, and the version
13613 imported will be the latest one found @emph{in this repository only}.
13619 Import metadata for a Go module using
13620 @uref{https://proxy.golang.org, proxy.golang.org}.
13623 guix import go gopkg.in/yaml.v2
13626 It is possible to use a package specification with a @code{@@VERSION}
13627 suffix to import a specific version.
13629 Additional options include:
13634 Traverse the dependency graph of the given upstream package recursively
13635 and generate package expressions for all those packages that are not yet
13637 @item --pin-versions
13638 When using this option, the importer preserves the exact versions of the
13639 Go modules dependencies instead of using their latest available
13640 versions. This can be useful when attempting to import packages that
13641 recursively depend on former versions of themselves to build. When
13642 using this mode, the symbol of the package is made by appending the
13643 version to its name, so that multiple versions of the same package can
13649 Import metadata for @uref{https://wiki.call-cc.org/eggs, CHICKEN eggs}.
13650 The information is taken from @file{PACKAGE.egg} files found in the
13651 @uref{git://code.call-cc.org/eggs-5-all, eggs-5-all} Git
13652 repository. However, it does not provide all the information that we
13653 need, there is no ``description'' field, and the licenses used are not
13654 always precise (BSD is often used instead of BSD-N).
13657 guix import egg sourcehut
13660 You can also ask for a specific version:
13663 guix import egg arrays@@1.0
13666 Additional options include:
13670 Traverse the dependency graph of the given upstream package recursively
13671 and generate package expressions for all those packages that are not yet
13677 Import metadata from the hex.pm Erlang and Elixir package repository
13678 @uref{https://hex.pm, hex.pm}, as in this example:
13681 guix import hexpm stun
13684 The importer tries to determine the build system used by the package.
13686 The hexpm importer also allows you to specify a version string:
13689 guix import hexpm cf@@0.3.0
13692 Additional options include:
13697 Traverse the dependency graph of the given upstream package recursively
13698 and generate package expressions for all those packages that are not yet
13703 The structure of the @command{guix import} code is modular. It would be
13704 useful to have more importers for other package formats, and your help
13705 is welcome here (@pxref{Contributing}).
13707 @node Invoking guix refresh
13708 @section Invoking @command{guix refresh}
13710 @cindex @command {guix refresh}
13711 The primary audience of the @command{guix refresh} command is packagers.
13712 As a user, you may be interested in the @option{--with-latest} option,
13713 which can bring you package update superpowers built upon @command{guix
13714 refresh} (@pxref{Package Transformation Options,
13715 @option{--with-latest}}). By default, @command{guix refresh} reports
13716 any packages provided by the distribution that are outdated compared to
13717 the latest upstream version, like this:
13721 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
13722 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
13725 Alternatively, one can specify packages to consider, in which case a
13726 warning is emitted for packages that lack an updater:
13729 $ guix refresh coreutils guile guile-ssh
13730 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
13731 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
13734 @command{guix refresh} browses the upstream repository of each package and determines
13735 the highest version number of the releases therein. The command
13736 knows how to update specific types of packages: GNU packages, ELPA
13737 packages, etc.---see the documentation for @option{--type} below. There
13738 are many packages, though, for which it lacks a method to determine
13739 whether a new upstream release is available. However, the mechanism is
13740 extensible, so feel free to get in touch with us to add a new method!
13745 Consider the packages specified, and all the packages upon which they depend.
13748 $ guix refresh --recursive coreutils
13749 gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
13750 gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
13751 gnu/packages/xml.scm:68:2: warning: no updater for expat
13752 gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
13758 Sometimes the upstream name differs from the package name used in Guix,
13759 and @command{guix refresh} needs a little help. Most updaters honor the
13760 @code{upstream-name} property in package definitions, which can be used
13764 (define-public network-manager
13766 (name "network-manager")
13768 (properties '((upstream-name . "NetworkManager")))))
13771 When passed @option{--update}, it modifies distribution source files to
13772 update the version numbers and source tarball hashes of those package
13773 recipes (@pxref{Defining Packages}). This is achieved by downloading
13774 each package's latest source tarball and its associated OpenPGP
13775 signature, authenticating the downloaded tarball against its signature
13776 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
13777 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
13780 key used to sign the tarball is missing from the user's keyring, an
13781 attempt is made to automatically retrieve it from a public key server;
13782 when this is successful, the key is added to the user's keyring; otherwise,
13783 @command{guix refresh} reports an error.
13785 The following options are supported:
13789 @item --expression=@var{expr}
13790 @itemx -e @var{expr}
13791 Consider the package @var{expr} evaluates to.
13793 This is useful to precisely refer to a package, as in this example:
13796 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
13799 This command lists the dependents of the ``final'' libc (essentially all
13804 Update distribution source files (package recipes) in place. This is
13805 usually run from a checkout of the Guix source tree (@pxref{Running
13806 Guix Before It Is Installed}):
13809 $ ./pre-inst-env guix refresh -s non-core -u
13812 @xref{Defining Packages}, for more information on package definitions.
13814 @item --select=[@var{subset}]
13815 @itemx -s @var{subset}
13816 Select all the packages in @var{subset}, one of @code{core} or
13819 The @code{core} subset refers to all the packages at the core of the
13820 distribution---i.e., packages that are used to build ``everything
13821 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
13822 changing one of these packages in the distribution entails a rebuild of
13823 all the others. Thus, such updates are an inconvenience to users in
13824 terms of build time or bandwidth used to achieve the upgrade.
13826 The @code{non-core} subset refers to the remaining packages. It is
13827 typically useful in cases where an update of the core packages would be
13830 @item --manifest=@var{file}
13831 @itemx -m @var{file}
13832 Select all the packages from the manifest in @var{file}. This is useful to
13833 check if any packages of the user manifest can be updated.
13835 @item --type=@var{updater}
13836 @itemx -t @var{updater}
13837 Select only packages handled by @var{updater} (may be a comma-separated
13838 list of updaters). Currently, @var{updater} may be one of:
13842 the updater for GNU packages;
13844 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
13846 the updater for packages hosted at @uref{https://sourceforge.net, SourceForge};
13848 the updater for GNOME packages;
13850 the updater for KDE packages;
13852 the updater for X.org packages;
13854 the updater for packages hosted on kernel.org;
13856 the updater for @uref{https://wiki.call-cc.org/eggs/, Egg} packages;
13858 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
13860 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
13862 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
13864 the updater for @uref{https://www.cpan.org/, CPAN} packages;
13866 the updater for @uref{https://pypi.python.org, PyPI} packages.
13868 the updater for @uref{https://rubygems.org, RubyGems} packages.
13870 the updater for @uref{https://github.com, GitHub} packages.
13872 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
13874 the updater for @uref{https://www.stackage.org, Stackage} packages.
13876 the updater for @uref{https://crates.io, Crates} packages.
13878 the updater for @uref{https://launchpad.net, Launchpad} packages.
13880 a generic updater that crawls the HTML page where the source tarball of
13881 the package is hosted, when applicable.
13884 a generic updater for packages hosted on Git repositories. It tries to
13885 be smart about parsing Git tag names, but if it is not able to parse the
13886 tag name and compare tags correctly, users can define the following
13887 properties for a package.
13890 @item @code{release-tag-prefix}: a regular expression for matching a prefix of
13893 @item @code{release-tag-suffix}: a regular expression for matching a suffix of
13896 @item @code{release-tag-version-delimiter}: a string used as the delimiter in
13897 the tag name for separating the numbers of the version.
13899 @item @code{accept-pre-releases}: by default, the updater will ignore
13900 pre-releases; to make it also look for pre-releases, set the this
13901 property to @code{#t}.
13910 '((release-tag-prefix . "^release0-")
13911 (release-tag-suffix . "[a-z]?$")
13912 (release-tag-version-delimiter . ":"))))
13918 For instance, the following command only checks for updates of Emacs
13919 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
13922 $ guix refresh --type=elpa,cran
13923 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
13924 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
13927 @item --list-updaters
13928 List available updaters and exit (see @option{--type} above).
13930 For each updater, display the fraction of packages it covers; at the
13931 end, display the fraction of packages covered by all these updaters.
13934 In addition, @command{guix refresh} can be passed one or more package
13935 names, as in this example:
13938 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
13942 The command above specifically updates the @code{emacs} and
13943 @code{idutils} packages. The @option{--select} option would have no
13944 effect in this case. You might also want to update definitions that
13945 correspond to the packages installed in your profile:
13948 $ ./pre-inst-env guix refresh -u \
13949 $(guix package --list-installed | cut -f1)
13952 When considering whether to upgrade a package, it is sometimes
13953 convenient to know which packages would be affected by the upgrade and
13954 should be checked for compatibility. For this the following option may
13955 be used when passing @command{guix refresh} one or more package names:
13959 @item --list-dependent
13961 List top-level dependent packages that would need to be rebuilt as a
13962 result of upgrading one or more packages.
13964 @xref{Invoking guix graph, the @code{reverse-package} type of
13965 @command{guix graph}}, for information on how to visualize the list of
13966 dependents of a package.
13970 Be aware that the @option{--list-dependent} option only
13971 @emph{approximates} the rebuilds that would be required as a result of
13972 an upgrade. More rebuilds might be required under some circumstances.
13975 $ guix refresh --list-dependent flex
13976 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
13977 hop@@2.4.0 emacs-geiser@@0.13 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
13980 The command above lists a set of packages that could be built to check
13981 for compatibility with an upgraded @code{flex} package.
13985 @item --list-transitive
13986 List all the packages which one or more packages depend upon.
13989 $ guix refresh --list-transitive flex
13990 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
13991 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{}
13996 The command above lists a set of packages which, when changed, would cause
13997 @code{flex} to be rebuilt.
13999 The following options can be used to customize GnuPG operation:
14003 @item --gpg=@var{command}
14004 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
14005 for in @code{$PATH}.
14007 @item --keyring=@var{file}
14008 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
14009 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
14010 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
14011 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
14012 information on a tool to manipulate keybox files).
14014 When this option is omitted, @command{guix refresh} uses
14015 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
14016 signing keys. OpenPGP signatures are checked against keys from this keyring;
14017 missing keys are downloaded to this keyring as well (see
14018 @option{--key-download} below).
14020 You can export keys from your default GPG keyring into a keybox file using
14021 commands like this one:
14024 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
14027 Likewise, you can fetch keys to a specific keybox file like this:
14030 gpg --no-default-keyring --keyring mykeyring.kbx \
14031 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
14034 @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
14035 Privacy Guard}, for more information on GPG's @option{--keyring} option.
14037 @item --key-download=@var{policy}
14038 Handle missing OpenPGP keys according to @var{policy}, which may be one
14043 Always download missing OpenPGP keys from the key server, and add them
14044 to the user's GnuPG keyring.
14047 Never try to download missing OpenPGP keys. Instead just bail out.
14050 When a package signed with an unknown OpenPGP key is encountered, ask
14051 the user whether to download it or not. This is the default behavior.
14054 @item --key-server=@var{host}
14055 Use @var{host} as the OpenPGP key server when importing a public key.
14057 @item --load-path=@var{directory}
14058 @itemx -L @var{directory}
14059 Add @var{directory} to the front of the package module search path
14060 (@pxref{Package Modules}).
14062 This allows users to define their own packages and make them visible to
14063 the command-line tools.
14067 The @code{github} updater uses the
14068 @uref{https://developer.github.com/v3/, GitHub API} to query for new
14069 releases. When used repeatedly e.g.@: when refreshing all packages,
14070 GitHub will eventually refuse to answer any further API requests. By
14071 default 60 API requests per hour are allowed, and a full refresh on all
14072 GitHub packages in Guix requires more than this. Authentication with
14073 GitHub through the use of an API token alleviates these limits. To use
14074 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
14075 token procured from @uref{https://github.com/settings/tokens} or
14079 @node Invoking guix style
14080 @section Invoking @command{guix style}
14082 The @command{guix style} command helps users and packagers alike style
14083 their package definitions and configuration files according to the
14084 latest fashionable trends. It can either reformat whole files, with the
14085 @option{--whole-file} option, or apply specific @dfn{styling rules} to
14086 individual package definitions. The command currently provides the
14087 following styling rules:
14091 formatting package definitions according to the project's conventions
14092 (@pxref{Formatting Code});
14095 rewriting package inputs to the ``new style'', as explained below.
14098 The way package inputs are written is going through a transition
14099 (@pxref{package Reference}, for more on package inputs). Until version
14100 1.3.0, package inputs were written using the ``old style'', where each
14101 input was given an explicit label, most of the time the package name:
14106 ;; The "old style" (deprecated).
14107 (inputs `(("libunistring" ,libunistring)
14108 ("libffi" ,libffi))))
14111 Today, the old style is deprecated and the preferred style looks like
14117 ;; The "new style".
14118 (inputs (list libunistring libffi)))
14121 Likewise, uses of @code{alist-delete} and friends to manipulate inputs
14122 is now deprecated in favor of @code{modify-inputs} (@pxref{Defining
14123 Package Variants}, for more info on @code{modify-inputs}).
14125 In the vast majority of cases, this is a purely mechanical change on the
14126 surface syntax that does not even incur a package rebuild. Running
14127 @command{guix style -S inputs} can do that for you, whether you're working on
14128 packages in Guix proper or in an external channel.
14130 The general syntax is:
14133 guix style [@var{options}] @var{package}@dots{}
14136 This causes @command{guix style} to analyze and rewrite the definition
14137 of @var{package}@dots{} or, when @var{package} is omitted, of @emph{all}
14138 the packages. The @option{--styling} or @option{-S} option allows you
14139 to select the style rule, the default rule being @code{format}---see
14142 To reformat entire source files, the syntax is:
14145 guix style --whole-file @var{file}@dots{}
14148 The available options are listed below.
14153 Show source file locations that would be edited but do not modify them.
14157 Reformat the given files in their entirety. In that case, subsequent
14158 arguments are interpreted as file names (rather than package names), and
14159 the @option{--styling} option has no effect.
14161 As an example, here is how you might reformat your operating system
14162 configuration (you need write permissions for the file):
14165 guix style -f /etc/config.scm
14168 @item --styling=@var{rule}
14169 @itemx -S @var{rule}
14170 Apply @var{rule}, one of the following styling rules:
14174 Format the given package definition(s)---this is the default styling
14175 rule. For example, a packager running Guix on a checkout
14176 (@pxref{Running Guix Before It Is Installed}) might want to reformat the
14177 definition of the Coreutils package like so:
14180 ./pre-inst-env guix style coreutils
14184 Rewrite package inputs to the ``new style'', as described above. This
14185 is how you would rewrite inputs of package @code{whatnot} in your own
14189 guix style -L ~/my/channel -S inputs whatnot
14192 Rewriting is done in a conservative way: preserving comments and bailing
14193 out if it cannot make sense of the code that appears in an inputs field.
14194 The @option{--input-simplification} option described below provides
14195 fine-grain control over when inputs should be simplified.
14198 @item --list-stylings
14200 List and describe the available styling rules and exit.
14202 @item --load-path=@var{directory}
14203 @itemx -L @var{directory}
14204 Add @var{directory} to the front of the package module search path
14205 (@pxref{Package Modules}).
14207 @item --expression=@var{expr}
14208 @itemx -e @var{expr}
14209 Style the package @var{expr} evaluates to.
14211 For example, running:
14214 guix style -e '(@@ (gnu packages gcc) gcc-5)'
14217 styles the @code{gcc-5} package definition.
14219 @item --input-simplification=@var{policy}
14220 When using the @code{inputs} styling rule, with @samp{-S inputs}, this
14221 option specifies the package input simplification policy for cases where
14222 an input label does not match the corresponding package name.
14223 @var{policy} may be one of the following:
14227 Simplify inputs only when the change is ``silent'', meaning that the
14228 package does not need to be rebuilt (its derivation is unchanged).
14231 Simplify inputs only when that is ``safe'' to do: the package might need
14232 to be rebuilt, but the change is known to have no observable effect.
14235 Simplify inputs even when input labels do not match package names, and
14236 even if that might have an observable effect.
14239 The default is @code{silent}, meaning that input simplifications do not
14240 trigger any package rebuild.
14243 @node Invoking guix lint
14244 @section Invoking @command{guix lint}
14246 @cindex @command{guix lint}
14247 @cindex package, checking for errors
14248 The @command{guix lint} command is meant to help package developers avoid
14249 common errors and use a consistent style. It runs a number of checks on
14250 a given set of packages in order to find common mistakes in their
14251 definitions. Available @dfn{checkers} include (see
14252 @option{--list-checkers} for a complete list):
14257 Validate certain typographical and stylistic rules about package
14258 descriptions and synopses.
14260 @item inputs-should-be-native
14261 Identify inputs that should most likely be native inputs.
14267 @itemx source-file-name
14268 Probe @code{home-page} and @code{source} URLs and report those that are
14269 invalid. Suggest a @code{mirror://} URL when applicable. If the
14270 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
14271 URL@. Check that the source file name is meaningful, e.g.@: is not just a
14272 version number or ``git-checkout'', without a declared @code{file-name}
14273 (@pxref{origin Reference}).
14275 @item source-unstable-tarball
14276 Parse the @code{source} URL to determine if a tarball from GitHub is
14277 autogenerated or if it is a release tarball. Unfortunately GitHub's
14278 autogenerated tarballs are sometimes regenerated.
14281 Check that the derivation of the given packages can be successfully
14282 computed for all the supported systems (@pxref{Derivations}).
14284 @item profile-collisions
14285 Check whether installing the given packages in a profile would lead to
14286 collisions. Collisions occur when several packages with the same name
14287 but a different version or a different store file name are propagated.
14288 @xref{package Reference, @code{propagated-inputs}}, for more information
14289 on propagated inputs.
14292 @cindex Software Heritage, source code archive
14293 @cindex archival of source code, Software Heritage
14294 Checks whether the package's source code is archived at
14295 @uref{https://www.softwareheritage.org, Software Heritage}.
14297 When the source code that is not archived comes from a version-control system
14298 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
14299 ``save'' request so that it eventually archives it. This ensures that the
14300 source will remain available in the long term, and that Guix can fall back to
14301 Software Heritage should the source code disappear from its original host.
14302 The status of recent ``save'' requests can be
14303 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
14305 When source code is a tarball obtained with @code{url-fetch}, simply print a
14306 message when it is not archived. As of this writing, Software Heritage does
14307 not allow requests to save arbitrary tarballs; we are working on ways to
14308 ensure that non-VCS source code is also archived.
14311 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
14312 request rate per IP address}. When the limit is reached, @command{guix lint}
14313 prints a message and the @code{archival} checker stops doing anything until
14314 that limit has been reset.
14317 @cindex security vulnerabilities
14318 @cindex CVE, Common Vulnerabilities and Exposures
14319 Report known vulnerabilities found in the Common Vulnerabilities and
14320 Exposures (CVE) databases of the current and past year
14321 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
14324 To view information about a particular vulnerability, visit pages such as:
14328 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
14330 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
14334 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
14335 @code{CVE-2015-7554}.
14337 Package developers can specify in package recipes the
14338 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
14339 name and version of the package when they differ from the name or version
14340 that Guix uses, as in this example:
14346 ;; CPE calls this package "grub2".
14347 (properties '((cpe-name . "grub2")
14348 (cpe-version . "2.3"))))
14351 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
14352 Some entries in the CVE database do not specify which version of a
14353 package they apply to, and would thus ``stick around'' forever. Package
14354 developers who found CVE alerts and verified they can be ignored can
14355 declare them as in this example:
14361 ;; These CVEs no longer apply and can be safely ignored.
14362 (properties `((lint-hidden-cve . ("CVE-2011-0433"
14365 "CVE-2011-5244")))))
14369 Warn about obvious source code formatting issues: trailing white space,
14370 use of tabulations, etc.
14373 Report old-style input labels that do not match the name of the
14374 corresponding package. This aims to help migrate from the ``old input
14375 style''. @xref{package Reference}, for more information on package
14376 inputs and input styles. @xref{Invoking guix style}, on how to migrate
14380 The general syntax is:
14383 guix lint @var{options} @var{package}@dots{}
14386 If no package is given on the command line, then all packages are checked.
14387 The @var{options} may be zero or more of the following:
14390 @item --list-checkers
14392 List and describe all the available checkers that will be run on packages
14397 Only enable the checkers specified in a comma-separated list using the
14398 names returned by @option{--list-checkers}.
14402 Only disable the checkers specified in a comma-separated list using the
14403 names returned by @option{--list-checkers}.
14405 @item --expression=@var{expr}
14406 @itemx -e @var{expr}
14407 Consider the package @var{expr} evaluates to.
14409 This is useful to unambiguously designate packages, as in this example:
14412 guix lint -c archival -e '(@@ (gnu packages guile) guile-3.0)'
14417 Only enable the checkers that do not depend on Internet access.
14419 @item --load-path=@var{directory}
14420 @itemx -L @var{directory}
14421 Add @var{directory} to the front of the package module search path
14422 (@pxref{Package Modules}).
14424 This allows users to define their own packages and make them visible to
14425 the command-line tools.
14429 @node Invoking guix size
14430 @section Invoking @command{guix size}
14433 @cindex package size
14435 @cindex @command{guix size}
14436 The @command{guix size} command helps package developers profile the
14437 disk usage of packages. It is easy to overlook the impact of an
14438 additional dependency added to a package, or the impact of using a
14439 single output for a package that could easily be split (@pxref{Packages
14440 with Multiple Outputs}). Such are the typical issues that
14441 @command{guix size} can highlight.
14443 The command can be passed one or more package specifications
14444 such as @code{gcc@@4.8}
14445 or @code{guile:debug}, or a file name in the store. Consider this
14449 $ guix size coreutils
14450 store item total self
14451 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
14452 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
14453 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
14454 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
14455 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
14456 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
14457 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
14458 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
14463 The store items listed here constitute the @dfn{transitive closure} of
14464 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
14465 would be returned by:
14468 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
14471 Here the output shows three columns next to store items. The first column,
14472 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
14473 the store item---that is, its own size plus the size of all its
14474 dependencies. The next column, labeled ``self'', shows the size of the
14475 item itself. The last column shows the ratio of the size of the item
14476 itself to the space occupied by all the items listed here.
14478 In this example, we see that the closure of Coreutils weighs in at
14479 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
14480 libraries. (That libc and GCC's libraries represent a large fraction of
14481 the closure is not a problem @i{per se} because they are always available
14482 on the system anyway.)
14484 Since the command also accepts store file names, assessing the size of
14485 a build result is straightforward:
14488 guix size $(guix system build config.scm)
14491 When the package(s) passed to @command{guix size} are available in the
14492 store@footnote{More precisely, @command{guix size} looks for the
14493 @emph{ungrafted} variant of the given package(s), as returned by
14494 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
14495 for information on grafts.}, @command{guix size} queries the daemon to determine its
14496 dependencies, and measures its size in the store, similar to @command{du
14497 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
14500 When the given packages are @emph{not} in the store, @command{guix size}
14501 reports information based on the available substitutes
14502 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
14503 store items that are not even on disk, only available remotely.
14505 You can also specify several package names:
14508 $ guix size coreutils grep sed bash
14509 store item total self
14510 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
14511 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
14512 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
14513 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
14519 In this example we see that the combination of the four packages takes
14520 102.3@tie{}MiB in total, which is much less than the sum of each closure
14521 since they have a lot of dependencies in common.
14523 When looking at the profile returned by @command{guix size}, you may
14524 find yourself wondering why a given package shows up in the profile at
14525 all. To understand it, you can use @command{guix graph --path -t
14526 references} to display the shortest path between the two packages
14527 (@pxref{Invoking guix graph}).
14529 The available options are:
14533 @item --substitute-urls=@var{urls}
14534 Use substitute information from @var{urls}.
14535 @xref{client-substitute-urls, the same option for @code{guix build}}.
14537 @item --sort=@var{key}
14538 Sort lines according to @var{key}, one of the following options:
14542 the size of each item (the default);
14544 the total size of the item's closure.
14547 @item --map-file=@var{file}
14548 Write a graphical map of disk usage in PNG format to @var{file}.
14550 For the example above, the map looks like this:
14552 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
14553 produced by @command{guix size}}
14555 This option requires that
14556 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
14557 installed and visible in Guile's module search path. When that is not
14558 the case, @command{guix size} fails as it tries to load it.
14560 @item --system=@var{system}
14561 @itemx -s @var{system}
14562 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
14564 @item --load-path=@var{directory}
14565 @itemx -L @var{directory}
14566 Add @var{directory} to the front of the package module search path
14567 (@pxref{Package Modules}).
14569 This allows users to define their own packages and make them visible to
14570 the command-line tools.
14573 @node Invoking guix graph
14574 @section Invoking @command{guix graph}
14577 @cindex @command{guix graph}
14578 @cindex package dependencies
14579 Packages and their dependencies form a @dfn{graph}, specifically a
14580 directed acyclic graph (DAG). It can quickly become difficult to have a
14581 mental model of the package DAG, so the @command{guix graph} command
14582 provides a visual representation of the DAG@. By default,
14583 @command{guix graph} emits a DAG representation in the input format of
14584 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
14585 directly to the @command{dot} command of Graphviz. It can also emit an
14586 HTML page with embedded JavaScript code to display a ``chord diagram''
14587 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
14588 emit Cypher queries to construct a graph in a graph database supporting
14589 the @uref{https://www.opencypher.org/, openCypher} query language. With
14590 @option{--path}, it simply displays the shortest path between two
14591 packages. The general syntax is:
14594 guix graph @var{options} @var{package}@dots{}
14597 For example, the following command generates a PDF file representing the
14598 package DAG for the GNU@tie{}Core Utilities, showing its build-time
14602 guix graph coreutils | dot -Tpdf > dag.pdf
14605 The output looks like this:
14607 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
14609 Nice little graph, no?
14611 You may find it more pleasant to navigate the graph interactively with
14612 @command{xdot} (from the @code{xdot} package):
14615 guix graph coreutils | xdot -
14618 But there is more than one graph! The one above is concise: it is the
14619 graph of package objects, omitting implicit inputs such as GCC, libc,
14620 grep, etc. It is often useful to have such a concise graph, but
14621 sometimes one may want to see more details. @command{guix graph} supports
14622 several types of graphs, allowing you to choose the level of detail:
14626 This is the default type used in the example above. It shows the DAG of
14627 package objects, excluding implicit dependencies. It is concise, but
14628 filters out many details.
14630 @item reverse-package
14631 This shows the @emph{reverse} DAG of packages. For example:
14634 guix graph --type=reverse-package ocaml
14637 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
14638 you are also interested in cases where OCaml is an implicit dependency, see
14639 @code{reverse-bag} below).
14641 Note that for core packages this can yield huge graphs. If all you want
14642 is to know the number of packages that depend on a given package, use
14643 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
14644 @option{--list-dependent}}).
14647 This is the package DAG, @emph{including} implicit inputs.
14649 For instance, the following command:
14652 guix graph --type=bag-emerged coreutils
14655 ...@: yields this bigger graph:
14657 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
14659 At the bottom of the graph, we see all the implicit inputs of
14660 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
14662 Now, note that the dependencies of these implicit inputs---that is, the
14663 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
14664 here, for conciseness.
14667 Similar to @code{bag-emerged}, but this time including all the bootstrap
14670 @item bag-with-origins
14671 Similar to @code{bag}, but also showing origins and their dependencies.
14674 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
14675 it also takes implicit dependencies into account. For example:
14678 guix graph -t reverse-bag dune
14682 ...@: yields the graph of all packages that depend on Dune, directly or
14683 indirectly. Since Dune is an @emph{implicit} dependency of many packages
14684 @i{via} @code{dune-build-system}, this shows a large number of packages,
14685 whereas @code{reverse-package} would show very few if any.
14688 This is the most detailed representation: It shows the DAG of
14689 derivations (@pxref{Derivations}) and plain store items. Compared to
14690 the above representation, many additional nodes are visible, including
14691 build scripts, patches, Guile modules, etc.
14693 For this type of graph, it is also possible to pass a @file{.drv} file
14694 name instead of a package name, as in:
14697 guix graph -t derivation $(guix system build -d my-config.scm)
14701 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
14702 For example, the following command shows the graph for the package
14703 module that defines the @code{guile} package:
14706 guix graph -t module guile | xdot -
14710 All the types above correspond to @emph{build-time dependencies}. The
14711 following graph type represents the @emph{run-time dependencies}:
14715 This is the graph of @dfn{references} of a package output, as returned
14716 by @command{guix gc --references} (@pxref{Invoking guix gc}).
14718 If the given package output is not available in the store, @command{guix
14719 graph} attempts to obtain dependency information from substitutes.
14721 Here you can also pass a store file name instead of a package name. For
14722 example, the command below produces the reference graph of your profile
14723 (which can be big!):
14726 guix graph -t references $(readlink -f ~/.guix-profile)
14730 This is the graph of the @dfn{referrers} of a store item, as returned by
14731 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
14733 This relies exclusively on local information from your store. For
14734 instance, let us suppose that the current Inkscape is available in 10
14735 profiles on your machine; @command{guix graph -t referrers inkscape}
14736 will show a graph rooted at Inkscape and with those 10 profiles linked
14739 It can help determine what is preventing a store item from being garbage
14744 @cindex shortest path, between packages
14745 Often, the graph of the package you are interested in does not fit on
14746 your screen, and anyway all you want to know is @emph{why} that package
14747 actually depends on some seemingly unrelated package. The
14748 @option{--path} option instructs @command{guix graph} to display the
14749 shortest path between two packages (or derivations, or store items,
14753 $ guix graph --path emacs libunistring
14756 libunistring@@0.9.10
14757 $ guix graph --path -t derivation emacs libunistring
14758 /gnu/store/@dots{}-emacs-26.3.drv
14759 /gnu/store/@dots{}-mailutils-3.9.drv
14760 /gnu/store/@dots{}-libunistring-0.9.10.drv
14761 $ guix graph --path -t references emacs libunistring
14762 /gnu/store/@dots{}-emacs-26.3
14763 /gnu/store/@dots{}-libidn2-2.2.0
14764 /gnu/store/@dots{}-libunistring-0.9.10
14767 Sometimes you still want to visualize the graph but would like to trim
14768 it so it can actually be displayed. One way to do it is via the
14769 @option{--max-depth} (or @option{-M}) option, which lets you specify the
14770 maximum depth of the graph. In the example below, we visualize only
14771 @code{libreoffice} and the nodes whose distance to @code{libreoffice} is
14775 guix graph -M 2 libreoffice | xdot -f fdp -
14778 Mind you, that's still a big ball of spaghetti, but at least
14779 @command{dot} can render it quickly and it can be browsed somewhat.
14781 The available options are the following:
14784 @item --type=@var{type}
14785 @itemx -t @var{type}
14786 Produce a graph output of @var{type}, where @var{type} must be one of
14787 the values listed above.
14790 List the supported graph types.
14792 @item --backend=@var{backend}
14793 @itemx -b @var{backend}
14794 Produce a graph using the selected @var{backend}.
14796 @item --list-backends
14797 List the supported graph backends.
14799 Currently, the available backends are Graphviz and d3.js.
14802 Display the shortest path between two nodes of the type specified by
14803 @option{--type}. The example below shows the shortest path between
14804 @code{libreoffice} and @code{llvm} according to the references of
14805 @code{libreoffice}:
14808 $ guix graph --path -t references libreoffice llvm
14809 /gnu/store/@dots{}-libreoffice-6.4.2.2
14810 /gnu/store/@dots{}-libepoxy-1.5.4
14811 /gnu/store/@dots{}-mesa-19.3.4
14812 /gnu/store/@dots{}-llvm-9.0.1
14815 @item --expression=@var{expr}
14816 @itemx -e @var{expr}
14817 Consider the package @var{expr} evaluates to.
14819 This is useful to precisely refer to a package, as in this example:
14822 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
14825 @item --system=@var{system}
14826 @itemx -s @var{system}
14827 Display the graph for @var{system}---e.g., @code{i686-linux}.
14829 The package dependency graph is largely architecture-independent, but there
14830 are some architecture-dependent bits that this option allows you to visualize.
14832 @item --load-path=@var{directory}
14833 @itemx -L @var{directory}
14834 Add @var{directory} to the front of the package module search path
14835 (@pxref{Package Modules}).
14837 This allows users to define their own packages and make them visible to
14838 the command-line tools.
14841 On top of that, @command{guix graph} supports all the usual package
14842 transformation options (@pxref{Package Transformation Options}). This
14843 makes it easy to view the effect of a graph-rewriting transformation
14844 such as @option{--with-input}. For example, the command below outputs
14845 the graph of @code{git} once @code{openssl} has been replaced by
14846 @code{libressl} everywhere in the graph:
14849 guix graph git --with-input=openssl=libressl
14852 So many possibilities, so much fun!
14854 @node Invoking guix publish
14855 @section Invoking @command{guix publish}
14857 @cindex @command{guix publish}
14858 The purpose of @command{guix publish} is to enable users to easily share
14859 their store with others, who can then use it as a substitute server
14860 (@pxref{Substitutes}).
14862 When @command{guix publish} runs, it spawns an HTTP server which allows
14863 anyone with network access to obtain substitutes from it. This means
14864 that any machine running Guix can also act as if it were a build farm,
14865 since the HTTP interface is compatible with Cuirass, the software behind
14866 the @code{@value{SUBSTITUTE-SERVER-1}} build farm.
14868 For security, each substitute is signed, allowing recipients to check
14869 their authenticity and integrity (@pxref{Substitutes}). Because
14870 @command{guix publish} uses the signing key of the system, which is only
14871 readable by the system administrator, it must be started as root; the
14872 @option{--user} option makes it drop root privileges early on.
14874 The signing key pair must be generated before @command{guix publish} is
14875 launched, using @command{guix archive --generate-key} (@pxref{Invoking
14878 When the @option{--advertise} option is passed, the server advertises
14879 its availability on the local network using multicast DNS (mDNS) and DNS
14880 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
14881 guile-avahi, Using Avahi in Guile Scheme Programs}).
14883 The general syntax is:
14886 guix publish @var{options}@dots{}
14889 Running @command{guix publish} without any additional arguments will
14890 spawn an HTTP server on port 8080:
14896 @cindex socket activation, for @command{guix publish}
14897 @command{guix publish} can also be started following the systemd
14898 ``socket activation'' protocol (@pxref{Service De- and Constructors,
14899 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
14901 Once a publishing server has been authorized, the daemon may download
14902 substitutes from it. @xref{Getting Substitutes from Other Servers}.
14904 By default, @command{guix publish} compresses archives on the fly as it
14905 serves them. This ``on-the-fly'' mode is convenient in that it requires
14906 no setup and is immediately available. However, when serving lots of
14907 clients, we recommend using the @option{--cache} option, which enables
14908 caching of the archives before they are sent to clients---see below for
14909 details. The @command{guix weather} command provides a handy way to
14910 check what a server provides (@pxref{Invoking guix weather}).
14912 As a bonus, @command{guix publish} also serves as a content-addressed
14913 mirror for source files referenced in @code{origin} records
14914 (@pxref{origin Reference}). For instance, assuming @command{guix
14915 publish} is running on @code{example.org}, the following URL returns the
14916 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
14917 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
14920 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
14923 Obviously, these URLs only work for files that are in the store; in
14924 other cases, they return 404 (``Not Found'').
14926 @cindex build logs, publication
14927 Build logs are available from @code{/log} URLs like:
14930 http://example.org/log/gwspk@dots{}-guile-2.2.3
14934 When @command{guix-daemon} is configured to save compressed build logs,
14935 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
14936 URLs return the compressed log as-is, with an appropriate
14937 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
14938 running @command{guix-daemon} with @option{--log-compression=gzip} since
14939 Web browsers can automatically decompress it, which is not the case with
14942 The following options are available:
14945 @item --port=@var{port}
14946 @itemx -p @var{port}
14947 Listen for HTTP requests on @var{port}.
14949 @item --listen=@var{host}
14950 Listen on the network interface for @var{host}. The default is to
14951 accept connections from any interface.
14953 @item --user=@var{user}
14954 @itemx -u @var{user}
14955 Change privileges to @var{user} as soon as possible---i.e., once the
14956 server socket is open and the signing key has been read.
14958 @item --compression[=@var{method}[:@var{level}]]
14959 @itemx -C [@var{method}[:@var{level}]]
14960 Compress data using the given @var{method} and @var{level}. @var{method} is
14961 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
14962 omitted, @code{gzip} is used.
14964 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
14965 to different compression levels: 1 is the fastest, and 9 is the best
14966 (CPU-intensive). The default is 3.
14968 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
14969 small increase in CPU usage; see
14970 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
14971 Web page}. However, @code{lzip} achieves low decompression throughput
14972 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
14973 bottleneck for someone who downloads over a fast network connection.
14975 The compression ratio of @code{zstd} is between that of @code{lzip} and
14976 that of @code{gzip}; its main advantage is a
14977 @uref{https://facebook.github.io/zstd/,high decompression speed}.
14979 Unless @option{--cache} is used, compression occurs on the fly and
14980 the compressed streams are not
14981 cached. Thus, to reduce load on the machine that runs @command{guix
14982 publish}, it may be a good idea to choose a low compression level, to
14983 run @command{guix publish} behind a caching proxy, or to use
14984 @option{--cache}. Using @option{--cache} has the advantage that it
14985 allows @command{guix publish} to add @code{Content-Length} HTTP header
14988 This option can be repeated, in which case every substitute gets compressed
14989 using all the selected methods, and all of them are advertised. This is
14990 useful when users may not support all the compression methods: they can select
14991 the one they support.
14993 @item --cache=@var{directory}
14994 @itemx -c @var{directory}
14995 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
14996 and only serve archives that are in cache.
14998 When this option is omitted, archives and meta-data are created
14999 on-the-fly. This can reduce the available bandwidth, especially when
15000 compression is enabled, since this may become CPU-bound. Another
15001 drawback of the default mode is that the length of archives is not known
15002 in advance, so @command{guix publish} does not add a
15003 @code{Content-Length} HTTP header to its responses, which in turn
15004 prevents clients from knowing the amount of data being downloaded.
15006 Conversely, when @option{--cache} is used, the first request for a store
15007 item (@i{via} a @code{.narinfo} URL) triggers a
15008 background process to @dfn{bake} the archive---computing its
15009 @code{.narinfo} and compressing the archive, if needed. Once the
15010 archive is cached in @var{directory}, subsequent requests succeed and
15011 are served directly from the cache, which guarantees that clients get
15012 the best possible bandwidth.
15014 That first @code{.narinfo} request nonetheless returns 200, provided the
15015 requested store item is ``small enough'', below the cache bypass
15016 threshold---see @option{--cache-bypass-threshold} below. That way,
15017 clients do not have to wait until the archive is baked. For larger
15018 store items, the first @code{.narinfo} request returns 404, meaning that
15019 clients have to wait until the archive is baked.
15021 The ``baking'' process is performed by worker threads. By default, one
15022 thread per CPU core is created, but this can be customized. See
15023 @option{--workers} below.
15025 When @option{--ttl} is used, cached entries are automatically deleted
15026 when they have expired.
15028 @item --workers=@var{N}
15029 When @option{--cache} is used, request the allocation of @var{N} worker
15030 threads to ``bake'' archives.
15032 @item --ttl=@var{ttl}
15033 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
15034 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
15035 days, @code{1m} means 1 month, and so on.
15037 This allows the user's Guix to keep substitute information in cache for
15038 @var{ttl}. However, note that @code{guix publish} does not itself
15039 guarantee that the store items it provides will indeed remain available
15040 for as long as @var{ttl}.
15042 Additionally, when @option{--cache} is used, cached entries that have
15043 not been accessed for @var{ttl} and that no longer have a corresponding
15044 item in the store, may be deleted.
15046 @item --negative-ttl=@var{ttl}
15047 Similarly produce @code{Cache-Control} HTTP headers to advertise the
15048 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
15049 which the HTTP 404 code is returned. By default, no negative TTL is
15052 This parameter can help adjust server load and substitute latency by
15053 instructing cooperating clients to be more or less patient when a store
15056 @item --cache-bypass-threshold=@var{size}
15057 When used in conjunction with @option{--cache}, store items smaller than
15058 @var{size} are immediately available, even when they are not yet in
15059 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
15060 for megabytes and so on. The default is @code{10M}.
15062 ``Cache bypass'' allows you to reduce the publication delay for clients
15063 at the expense of possibly additional I/O and CPU use on the server
15064 side: depending on the client access patterns, those store items can end
15065 up being baked several times until a copy is available in cache.
15067 Increasing the threshold may be useful for sites that have few users, or
15068 to guarantee that users get substitutes even for store items that are
15071 @item --nar-path=@var{path}
15072 Use @var{path} as the prefix for the URLs of ``nar'' files
15073 (@pxref{Invoking guix archive, normalized archives}).
15075 By default, nars are served at a URL such as
15076 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
15077 change the @code{/nar} part to @var{path}.
15079 @item --public-key=@var{file}
15080 @itemx --private-key=@var{file}
15081 Use the specific @var{file}s as the public/private key pair used to sign
15082 the store items being published.
15084 The files must correspond to the same key pair (the private key is used
15085 for signing and the public key is merely advertised in the signature
15086 metadata). They must contain keys in the canonical s-expression format
15087 as produced by @command{guix archive --generate-key} (@pxref{Invoking
15088 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
15089 @file{/etc/guix/signing-key.sec} are used.
15091 @item --repl[=@var{port}]
15092 @itemx -r [@var{port}]
15093 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
15094 Reference Manual}) on @var{port} (37146 by default). This is used
15095 primarily for debugging a running @command{guix publish} server.
15098 Enabling @command{guix publish} on Guix System is a one-liner: just
15099 instantiate a @code{guix-publish-service-type} service in the @code{services} field
15100 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
15101 @code{guix-publish-service-type}}).
15103 If you are instead running Guix on a ``foreign distro'', follow these
15108 If your host distro uses the systemd init system:
15111 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
15112 /etc/systemd/system/
15113 # systemctl start guix-publish && systemctl enable guix-publish
15117 If your host distro uses the Upstart init system:
15120 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
15121 # start guix-publish
15125 Otherwise, proceed similarly with your distro's init system.
15128 @node Invoking guix challenge
15129 @section Invoking @command{guix challenge}
15131 @cindex reproducible builds
15132 @cindex verifiable builds
15133 @cindex @command{guix challenge}
15135 Do the binaries provided by this server really correspond to the source
15136 code it claims to build? Is a package build process deterministic?
15137 These are the questions the @command{guix challenge} command attempts to
15140 The former is obviously an important question: Before using a substitute
15141 server (@pxref{Substitutes}), one had better @emph{verify} that it
15142 provides the right binaries, and thus @emph{challenge} it. The latter
15143 is what enables the former: If package builds are deterministic, then
15144 independent builds of the package should yield the exact same result,
15145 bit for bit; if a server provides a binary different from the one
15146 obtained locally, it may be either corrupt or malicious.
15148 We know that the hash that shows up in @file{/gnu/store} file names is
15149 the hash of all the inputs of the process that built the file or
15150 directory---compilers, libraries, build scripts,
15151 etc. (@pxref{Introduction}). Assuming deterministic build processes,
15152 one store file name should map to exactly one build output.
15153 @command{guix challenge} checks whether there is, indeed, a single
15154 mapping by comparing the build outputs of several independent builds of
15155 any given store item.
15157 The command output looks like this:
15161 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org" \
15162 openssl git pius coreutils grep
15163 updating substitutes from 'https://@value{SUBSTITUTE-SERVER-1}'... 100.0%
15164 updating substitutes from 'https://guix.example.org'... 100.0%
15165 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
15166 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15167 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15168 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
15170 /lib/libcrypto.so.1.1
15173 /gnu/store/@dots{}-git-2.5.0 contents differ:
15174 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
15175 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
15176 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
15178 /libexec/git-core/git-fsck
15180 /gnu/store/@dots{}-pius-2.1.1 contents differ:
15181 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15182 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15183 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
15185 /share/man/man1/pius.1.gz
15189 5 store items were analyzed:
15190 - 2 (40.0%) were identical
15191 - 3 (60.0%) differed
15192 - 0 (0.0%) were inconclusive
15196 In this example, @command{guix challenge} queries all the substitute
15197 servers for each of the fives packages specified on the command line.
15198 It then reports those store items for which the servers obtained a
15199 result different from the local build (if it exists) and/or different
15200 from one another; here, the @samp{local hash} lines indicate that a
15201 local build result was available for each of these packages and shows
15204 @cindex non-determinism, in package builds
15205 As an example, @code{guix.example.org} always gets a different answer.
15206 Conversely, @code{@value{SUBSTITUTE-SERVER-1}} agrees with local builds, except in the
15207 case of Git. This might indicate that the build process of Git is
15208 non-deterministic, meaning that its output varies as a function of
15209 various things that Guix does not fully control, in spite of building
15210 packages in isolated environments (@pxref{Features}). Most common
15211 sources of non-determinism include the addition of timestamps in build
15212 results, the inclusion of random numbers, and directory listings sorted
15213 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
15216 To find out what is wrong with this Git binary, the easiest approach is
15220 guix challenge git \
15221 --diff=diffoscope \
15222 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
15225 This automatically invokes @command{diffoscope}, which displays detailed
15226 information about files that differ.
15228 Alternatively, we can do something along these lines (@pxref{Invoking guix
15232 $ wget -q -O - https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-git-2.5.0 \
15233 | lzip -d | guix archive -x /tmp/git
15234 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
15237 This command shows the difference between the files resulting from the
15238 local build, and the files resulting from the build on
15239 @code{@value{SUBSTITUTE-SERVER-1}} (@pxref{Overview, Comparing and Merging Files,,
15240 diffutils, Comparing and Merging Files}). The @command{diff} command
15241 works great for text files. When binary files differ, a better option
15242 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
15243 visualize differences for all kinds of files.
15245 Once you have done that work, you can tell whether the differences are due
15246 to a non-deterministic build process or to a malicious server. We try
15247 hard to remove sources of non-determinism in packages to make it easier
15248 to verify substitutes, but of course, this is a process that
15249 involves not just Guix, but a large part of the free software community.
15250 In the meantime, @command{guix challenge} is one tool to help address
15253 If you are writing packages for Guix, you are encouraged to check
15254 whether @code{@value{SUBSTITUTE-SERVER-1}} and other substitute servers obtain the
15255 same build result as you did with:
15258 guix challenge @var{package}
15261 The general syntax is:
15264 guix challenge @var{options} @var{argument}@dots{}
15268 where @var{argument} is a package specification such as
15269 @code{guile@@2.0} or @code{glibc:debug} or, alternatively, a store file
15270 name as returned, for example, by @command{guix build} or @command{guix
15273 When a difference is found between the hash of a locally-built item and
15274 that of a server-provided substitute, or among substitutes provided by
15275 different servers, the command displays it as in the example above and
15276 its exit code is 2 (other non-zero exit codes denote other kinds of
15279 The one option that matters is:
15283 @item --substitute-urls=@var{urls}
15284 Consider @var{urls} the whitespace-separated list of substitute source
15285 URLs to compare to.
15287 @item --diff=@var{mode}
15288 Upon mismatches, show differences according to @var{mode}, one of:
15291 @item @code{simple} (the default)
15292 Show the list of files that differ.
15294 @item @code{diffoscope}
15295 @itemx @var{command}
15296 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
15297 two directories whose contents do not match.
15299 When @var{command} is an absolute file name, run @var{command} instead
15303 Do not show further details about the differences.
15306 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
15307 downloads the store items from the given substitute servers so that it
15312 Show details about matches (identical contents) in addition to
15313 information about mismatches.
15317 @node Invoking guix copy
15318 @section Invoking @command{guix copy}
15320 @cindex copy, of store items, over SSH
15321 @cindex SSH, copy of store items
15322 @cindex sharing store items across machines
15323 @cindex transferring store items across machines
15324 The @command{guix copy} command copies items from the store of one
15325 machine to that of another machine over a secure shell (SSH)
15326 connection@footnote{This command is available only when Guile-SSH was
15327 found. @xref{Requirements}, for details.}. For example, the following
15328 command copies the @code{coreutils} package, the user's profile, and all
15329 their dependencies over to @var{host}, logged in as @var{user}:
15332 guix copy --to=@var{user}@@@var{host} \
15333 coreutils $(readlink -f ~/.guix-profile)
15336 If some of the items to be copied are already present on @var{host},
15337 they are not actually sent.
15339 The command below retrieves @code{libreoffice} and @code{gimp} from
15340 @var{host}, assuming they are available there:
15343 guix copy --from=@var{host} libreoffice gimp
15346 The SSH connection is established using the Guile-SSH client, which is
15347 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
15348 @file{~/.ssh/config}, and uses the SSH agent for authentication.
15350 The key used to sign items that are sent must be accepted by the remote
15351 machine. Likewise, the key used by the remote machine to sign items you
15352 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
15353 own daemon. @xref{Invoking guix archive}, for more information about
15354 store item authentication.
15356 The general syntax is:
15359 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
15362 You must always specify one of the following options:
15365 @item --to=@var{spec}
15366 @itemx --from=@var{spec}
15367 Specify the host to send to or receive from. @var{spec} must be an SSH
15368 spec such as @code{example.org}, @code{charlie@@example.org}, or
15369 @code{charlie@@example.org:2222}.
15372 The @var{items} can be either package names, such as @code{gimp}, or
15373 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
15375 When specifying the name of a package to send, it is first built if
15376 needed, unless @option{--dry-run} was specified. Common build options
15377 are supported (@pxref{Common Build Options}).
15380 @node Invoking guix container
15381 @section Invoking @command{guix container}
15383 @cindex @command{guix container}
15385 As of version @value{VERSION}, this tool is experimental. The interface
15386 is subject to radical change in the future.
15389 The purpose of @command{guix container} is to manipulate processes
15390 running within an isolated environment, commonly known as a
15391 ``container'', typically created by the @command{guix shell}
15392 (@pxref{Invoking guix shell}) and @command{guix system container}
15393 (@pxref{Invoking guix system}) commands.
15395 The general syntax is:
15398 guix container @var{action} @var{options}@dots{}
15401 @var{action} specifies the operation to perform with a container, and
15402 @var{options} specifies the context-specific arguments for the action.
15404 The following actions are available:
15408 Execute a command within the context of a running container.
15413 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
15416 @var{pid} specifies the process ID of the running container.
15417 @var{program} specifies an executable file name within the root file
15418 system of the container. @var{arguments} are the additional options that
15419 will be passed to @var{program}.
15421 The following command launches an interactive login shell inside a
15422 Guix system container, started by @command{guix system container}, and whose
15423 process ID is 9001:
15426 guix container exec 9001 /run/current-system/profile/bin/bash --login
15429 Note that the @var{pid} cannot be the parent process of a container. It
15430 must be PID 1 of the container or one of its child processes.
15434 @node Invoking guix weather
15435 @section Invoking @command{guix weather}
15437 Occasionally you're grumpy because substitutes are lacking and you end
15438 up building packages by yourself (@pxref{Substitutes}). The
15439 @command{guix weather} command reports on substitute availability on the
15440 specified servers so you can have an idea of whether you'll be grumpy
15441 today. It can sometimes be useful info as a user, but it is primarily
15442 useful to people running @command{guix publish} (@pxref{Invoking guix
15445 @cindex statistics, for substitutes
15446 @cindex availability of substitutes
15447 @cindex substitute availability
15448 @cindex weather, substitute availability
15449 Here's a sample run:
15452 $ guix weather --substitute-urls=https://guix.example.org
15453 computing 5,872 package derivations for x86_64-linux...
15454 looking for 6,128 store items on https://guix.example.org..
15455 updating substitutes from 'https://guix.example.org'... 100.0%
15456 https://guix.example.org
15457 43.4% substitutes available (2,658 out of 6,128)
15458 7,032.5 MiB of nars (compressed)
15459 19,824.2 MiB on disk (uncompressed)
15460 0.030 seconds per request (182.9 seconds in total)
15461 33.5 requests per second
15463 9.8% (342 out of 3,470) of the missing items are queued
15465 x86_64-linux: 518 (59.7%)
15466 i686-linux: 221 (25.5%)
15467 aarch64-linux: 128 (14.8%)
15468 build rate: 23.41 builds per hour
15469 x86_64-linux: 11.16 builds per hour
15470 i686-linux: 6.03 builds per hour
15471 aarch64-linux: 6.41 builds per hour
15474 @cindex continuous integration, statistics
15475 As you can see, it reports the fraction of all the packages for which
15476 substitutes are available on the server---regardless of whether
15477 substitutes are enabled, and regardless of whether this server's signing
15478 key is authorized. It also reports the size of the compressed archives
15479 (``nars'') provided by the server, the size the corresponding store
15480 items occupy in the store (assuming deduplication is turned off), and
15481 the server's throughput. The second part gives continuous integration
15482 (CI) statistics, if the server supports it. In addition, using the
15483 @option{--coverage} option, @command{guix weather} can list ``important''
15484 package substitutes missing on the server (see below).
15486 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
15487 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
15488 challenge}, it ignores signatures on those substitutes, which is
15489 innocuous since the command only gathers statistics and cannot install
15492 The general syntax is:
15495 guix weather @var{options}@dots{} [@var{packages}@dots{}]
15498 When @var{packages} is omitted, @command{guix weather} checks the availability
15499 of substitutes for @emph{all} the packages, or for those specified with
15500 @option{--manifest}; otherwise it only considers the specified packages. It
15501 is also possible to query specific system types with @option{--system}.
15502 @command{guix weather} exits with a non-zero code when the fraction of
15503 available substitutes is below 100%.
15505 The available options are listed below.
15508 @item --substitute-urls=@var{urls}
15509 @var{urls} is the space-separated list of substitute server URLs to
15510 query. When this option is omitted, the default set of substitute
15511 servers is queried.
15513 @item --system=@var{system}
15514 @itemx -s @var{system}
15515 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
15516 option can be repeated, in which case @command{guix weather} will query
15517 substitutes for several system types.
15519 @item --manifest=@var{file}
15520 Instead of querying substitutes for all the packages, only ask for those
15521 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
15522 with the @code{-m} option of @command{guix package} (@pxref{Invoking
15525 This option can be repeated several times, in which case the manifests
15528 @item --coverage[=@var{count}]
15529 @itemx -c [@var{count}]
15530 Report on substitute coverage for packages: list packages with at least
15531 @var{count} dependents (zero by default) for which substitutes are
15532 unavailable. Dependent packages themselves are not listed: if @var{b} depends
15533 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
15534 @var{b} usually lacks substitutes as well. The result looks like this:
15537 $ guix weather --substitute-urls=@value{SUBSTITUTE-URLS} -c 10
15538 computing 8,983 package derivations for x86_64-linux...
15539 looking for 9,343 store items on @value{SUBSTITUTE-URLS}...
15540 updating substitutes from '@value{SUBSTITUTE-URLS}'... 100.0%
15541 @value{SUBSTITUTE-URLS}
15542 64.7% substitutes available (6,047 out of 9,343)
15544 2502 packages are missing from '@value{SUBSTITUTE-URLS}' for 'x86_64-linux', among which:
15545 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
15546 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
15547 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
15551 What this example shows is that @code{kcoreaddons} and presumably the 58
15552 packages that depend on it have no substitutes at
15553 @code{@value{SUBSTITUTE-SERVER-1}}; likewise for @code{qgpgme} and the 46
15554 packages that depend on it.
15556 If you are a Guix developer, or if you are taking care of this build farm,
15557 you'll probably want to have a closer look at these packages: they may simply
15560 @item --display-missing
15561 Display the list of store items for which substitutes are missing.
15564 @node Invoking guix processes
15565 @section Invoking @command{guix processes}
15567 The @command{guix processes} command can be useful to developers and system
15568 administrators, especially on multi-user machines and on build farms: it lists
15569 the current sessions (connections to the daemon), as well as information about
15570 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
15571 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
15572 listed.}. Here's an example of the information it returns:
15575 $ sudo guix processes
15578 ClientCommand: guix shell python
15582 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
15586 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15587 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
15588 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
15589 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
15591 ChildCommand: guix offload x86_64-linux 7200 1 28800
15593 ChildCommand: guix offload x86_64-linux 7200 1 28800
15595 ChildCommand: guix offload x86_64-linux 7200 1 28800
15598 In this example we see that @command{guix-daemon} has three clients:
15599 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
15600 integration tool; their process identifier (PID) is given by the
15601 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
15602 @command{guix-daemon} sub-process of this particular session.
15604 The @code{LockHeld} fields show which store items are currently locked
15605 by this session, which corresponds to store items being built or
15606 substituted (the @code{LockHeld} field is not displayed when
15607 @command{guix processes} is not running as root). Last, by looking at
15608 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
15609 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
15611 The output is in Recutils format so we can use the handy @command{recsel}
15612 command to select sessions of interest (@pxref{Selection Expressions,,,
15613 recutils, GNU recutils manual}). As an example, the command shows the command
15614 line and PID of the client that triggered the build of a Perl package:
15617 $ sudo guix processes | \
15618 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
15620 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15623 Additional options are listed below.
15626 @item --format=@var{format}
15627 @itemx -f @var{format}
15628 Produce output in the specified @var{format}, one of:
15632 The default option. It outputs a set of Session recutils records
15633 that include each @code{ChildProcess} as a field.
15636 Normalize the output records into record sets (@pxref{Record Sets,,,
15637 recutils, GNU recutils manual}). Normalizing into record sets allows
15638 joins across record types. The example below lists the PID of each
15639 @code{ChildProcess} and the associated PID for @code{Session} that
15640 spawned the @code{ChildProcess} where the @code{Session} was started
15641 using @command{guix build}.
15644 $ guix processes --format=normalized | \
15648 -p Session.PID,PID \
15649 -e 'Session.ClientCommand ~ "guix build"'
15662 @node Foreign Architectures
15663 @chapter Foreign Architectures
15665 You can target computers of different CPU architectures when producing
15666 packages (@pxref{Invoking guix package}), packs (@pxref{Invoking guix
15667 pack}) or full systems (@pxref{Invoking guix system}).
15669 GNU Guix supports two distinct mechanisms to target foreign
15675 @uref{https://en.wikipedia.org/wiki/Cross_compiler,cross-compilation}
15678 The native building mechanism which consists in building using the CPU
15679 instruction set of the foreign system you are targeting. It often
15680 requires emulation, using the QEMU program for instance.
15684 * Cross-Compilation:: Cross-compiling for another architecture.
15685 * Native Builds:: Targeting another architecture through native builds.
15688 @node Cross-Compilation
15689 @section Cross-Compilation
15691 @cindex foreign architectures
15692 The commands supporting cross-compilation are proposing the
15693 @option{--list-targets} and @option{--target} options.
15695 The @option{--list-targets} option lists all the supported targets that
15696 can be passed as an argument to @option{--target}.
15699 $ guix build --list-targets
15700 The available targets are:
15702 - aarch64-linux-gnu
15703 - arm-linux-gnueabihf
15707 - mips64el-linux-gnu
15708 - powerpc-linux-gnu
15709 - powerpc64le-linux-gnu
15710 - riscv64-linux-gnu
15712 - x86_64-w64-mingw32
15715 Targets are specified as GNU triplets (@pxref{Specifying Target
15716 Triplets, GNU configuration triplets,, autoconf, Autoconf}).
15718 Those triplets are passed to GCC and the other underlying compilers
15719 possibly involved when building a package, a system image or any other
15723 $ guix build --target=aarch64-linux-gnu hello
15724 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12
15726 $ file /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello
15727 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello: ELF
15728 64-bit LSB executable, ARM aarch64 @dots{}
15731 The major benefit of cross-compilation is that there are no performance
15732 penaly compared to emulation using QEMU. There are however higher risks
15733 that some packages fail to cross-compile because few users are using
15734 this mechanism extensively.
15736 @node Native Builds
15737 @section Native Builds
15739 The commands that support impersonating a specific system have the
15740 @option{--list-systems} and @option{--system} options.
15742 The @option{--list-systems} option lists all the supported systems that
15743 can be passed as an argument to @option{--system}.
15746 $ guix build --list-systems
15747 The available systems are:
15749 - x86_64-linux [current]
15756 - powerpc64le-linux
15759 $ guix build --system=i686-linux hello
15760 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12
15762 $ file /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello
15763 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello: ELF
15764 32-bit LSB executable, Intel 80386 @dots{}
15767 In the above example, the current system is @var{x86_64-linux}. The
15768 @var{hello} package is however built for the @var{i686-linux} system.
15770 This is possible because the @var{i686} CPU instruction set is a subset
15771 of the @var{x86_64}, hence @var{i686} targeting binaries can be run on
15774 Still in the context of the previous example, if picking the
15775 @var{aarch64-linux} system and the @command{guix build
15776 --system=aarch64-linux hello} has to build some derivations, an extra
15777 step might be needed.
15779 The @var{aarch64-linux} targeting binaries cannot directly be run on a
15780 @var{x86_64-linux} system. An emulation layer is requested. The GNU
15781 Guix daemon can take advantage of the Linux kernel
15782 @uref{https://en.wikipedia.org/wiki/Binfmt_misc,binfmt_misc} mechanism
15783 for that. In short, the Linux kernel can defer the execution of a
15784 binary targeting a foreign platform, here @var{aarch64-linux}, to a
15785 userspace program, usually an emulator.
15787 There is a service that registers QEMU as a backend for the
15788 @code{binfmt_misc} mechanism (@pxref{Virtualization Services,
15789 @code{qemu-binfmt-service-type}}). On Debian based foreign
15790 distributions, the alternative would be the @code{qemu-user-static}
15793 If the @code{binfmt_misc} mechanism is not setup correctly, the building
15794 will fail this way:
15797 $ guix build --system=armhf-linux hello --check
15799 @ unsupported-platform /gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv aarch64-linux
15800 while setting up the build environment: a `aarch64-linux' is required to
15801 build `/gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv', but
15802 I am a `x86_64-linux'@dots{}
15805 whereas, with the @code{binfmt_misc} mechanism correctly linked with
15806 QEMU, one can expect to see:
15809 $ guix build --system=armhf-linux hello --check
15810 /gnu/store/13xz4nghg39wpymivlwghy08yzj97hlj-hello-2.12
15813 The main advantage of native building compared to cross-compiling, is
15814 that more packages are likely to build correctly. However it comes at a
15815 price: compilation backed by QEMU is @emph{way slower} than
15816 cross-compilation, because every instruction needs to be emulated.
15818 The availability of substitutes for the architecture targeted by the
15819 @code{--system} option can mitigate this problem. An other way to work
15820 around it is to install GNU Guix on a machine whose CPU supports
15821 the targeted instruction set, and set it up as an offload machine
15822 (@pxref{Daemon Offload Setup}).
15824 @node System Configuration
15825 @chapter System Configuration
15827 @cindex system configuration
15828 Guix System supports a consistent whole-system configuration
15829 mechanism. By that we mean that all aspects of the global system
15830 configuration---such as the available system services, timezone and
15831 locale settings, user accounts---are declared in a single place. Such
15832 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
15834 One of the advantages of putting all the system configuration under the
15835 control of Guix is that it supports transactional system upgrades, and
15836 makes it possible to roll back to a previous system instantiation,
15837 should something go wrong with the new one (@pxref{Features}). Another
15838 advantage is that it makes it easy to replicate the exact same configuration
15839 across different machines, or at different points in time, without
15840 having to resort to additional administration tools layered on top of
15841 the own tools of the system.
15842 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
15844 This section describes this mechanism. First we focus on the system
15845 administrator's viewpoint---explaining how the system is configured and
15846 instantiated. Then we show how this mechanism can be extended, for
15847 instance to support new system services.
15850 * Using the Configuration System:: Customizing your GNU system.
15851 * operating-system Reference:: Detail of operating-system declarations.
15852 * File Systems:: Configuring file system mounts.
15853 * Mapped Devices:: Block device extra processing.
15854 * Swap Space:: Backing RAM with disk space.
15855 * User Accounts:: Specifying user accounts.
15856 * Keyboard Layout:: How the system interprets key strokes.
15857 * Locales:: Language and cultural convention settings.
15858 * Services:: Specifying system services.
15859 * Setuid Programs:: Programs running with elevated privileges.
15860 * X.509 Certificates:: Authenticating HTTPS servers.
15861 * Name Service Switch:: Configuring libc's name service switch.
15862 * Initial RAM Disk:: Linux-Libre bootstrapping.
15863 * Bootloader Configuration:: Configuring the boot loader.
15864 * Invoking guix system:: Instantiating a system configuration.
15865 * Invoking guix deploy:: Deploying a system configuration to a remote host.
15866 * Running Guix in a VM:: How to run Guix System in a virtual machine.
15867 * Defining Services:: Adding new service definitions.
15870 @node Using the Configuration System
15871 @section Using the Configuration System
15873 The operating system is configured by providing an
15874 @code{operating-system} declaration in a file that can then be passed to
15875 the @command{guix system} command (@pxref{Invoking guix system}). A
15876 simple setup, with the default system services, the default Linux-Libre
15877 kernel, initial RAM disk, and boot loader looks like this:
15879 @findex operating-system
15881 @include os-config-bare-bones.texi
15884 This example should be self-describing. Some of the fields defined
15885 above, such as @code{host-name} and @code{bootloader}, are mandatory.
15886 Others, such as @code{packages} and @code{services}, can be omitted, in
15887 which case they get a default value.
15889 Below we discuss the effect of some of the most important fields
15890 (@pxref{operating-system Reference}, for details about all the available
15891 fields), and how to @dfn{instantiate} the operating system using
15892 @command{guix system}.
15894 @unnumberedsubsec Bootloader
15896 @cindex legacy boot, on Intel machines
15897 @cindex BIOS boot, on Intel machines
15900 The @code{bootloader} field describes the method that will be used to boot
15901 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
15902 mode, as in the example above. However, more recent machines rely instead on
15903 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
15904 the @code{bootloader} field should contain something along these lines:
15907 (bootloader-configuration
15908 (bootloader grub-efi-bootloader)
15909 (targets '("/boot/efi")))
15912 @xref{Bootloader Configuration}, for more information on the available
15913 configuration options.
15915 @unnumberedsubsec Globally-Visible Packages
15917 @vindex %base-packages
15918 The @code{packages} field lists packages that will be globally visible
15919 on the system, for all user accounts---i.e., in every user's @env{PATH}
15920 environment variable---in addition to the per-user profiles
15921 (@pxref{Invoking guix package}). The @code{%base-packages} variable
15922 provides all the tools one would expect for basic user and administrator
15923 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
15924 the @command{mg} lightweight text editor, @command{find}, @command{grep},
15925 etc. The example above adds GNU@tie{}Screen to those,
15926 taken from the @code{(gnu packages screen)}
15927 module (@pxref{Package Modules}). The
15928 @code{(list package output)} syntax can be used to add a specific output
15932 (use-modules (gnu packages))
15933 (use-modules (gnu packages dns))
15937 (packages (cons (list isc-bind "utils")
15941 @findex specification->package
15942 Referring to packages by variable name, like @code{isc-bind} above, has
15943 the advantage of being unambiguous; it also allows typos and such to be
15944 diagnosed right away as ``unbound variables''. The downside is that one
15945 needs to know which module defines which package, and to augment the
15946 @code{use-package-modules} line accordingly. To avoid that, one can use
15947 the @code{specification->package} procedure of the @code{(gnu packages)}
15948 module, which returns the best package for a given name or name and
15952 (use-modules (gnu packages))
15956 (packages (append (map specification->package
15957 '("tcpdump" "htop" "gnupg@@2.0"))
15961 @unnumberedsubsec System Services
15964 @vindex %base-services
15965 The @code{services} field lists @dfn{system services} to be made
15966 available when the system starts (@pxref{Services}).
15967 The @code{operating-system} declaration above specifies that, in
15968 addition to the basic services, we want the OpenSSH secure shell
15969 daemon listening on port 2222 (@pxref{Networking Services,
15970 @code{openssh-service-type}}). Under the hood,
15971 @code{openssh-service-type} arranges so that @command{sshd} is started with the
15972 right command-line options, possibly with supporting configuration files
15973 generated as needed (@pxref{Defining Services}).
15975 @cindex customization, of services
15976 @findex modify-services
15977 Occasionally, instead of using the base services as is, you will want to
15978 customize them. To do this, use @code{modify-services} (@pxref{Service
15979 Reference, @code{modify-services}}) to modify the list.
15981 @anchor{auto-login to TTY} For example, suppose you want to modify
15982 @code{guix-daemon} and Mingetty (the console log-in) in the
15983 @code{%base-services} list (@pxref{Base Services,
15984 @code{%base-services}}). To do that, you can write the following in
15985 your operating system declaration:
15988 (define %my-services
15989 ;; My very own list of services.
15990 (modify-services %base-services
15991 (guix-service-type config =>
15992 (guix-configuration
15994 ;; Fetch substitutes from example.org.
15996 (list "https://example.org/guix"
15997 "https://ci.guix.gnu.org"))))
15998 (mingetty-service-type config =>
15999 (mingetty-configuration
16001 ;; Automatically log in as "guest".
16002 (auto-login "guest")))))
16006 (services %my-services))
16009 This changes the configuration---i.e., the service parameters---of the
16010 @code{guix-service-type} instance, and that of all the
16011 @code{mingetty-service-type} instances in the @code{%base-services} list
16012 (@pxref{Auto-Login to a Specific TTY, see the cookbook for how to
16013 auto-login one user to a specific TTY,, guix-cookbook, GNU Guix Cookbook})).
16014 Observe how this is accomplished: first, we arrange for the original
16015 configuration to be bound to the identifier @code{config} in the
16016 @var{body}, and then we write the @var{body} so that it evaluates to the
16017 desired configuration. In particular, notice how we use @code{inherit}
16018 to create a new configuration which has the same values as the old
16019 configuration, but with a few modifications.
16021 @cindex encrypted disk
16022 The configuration for a typical ``desktop'' usage, with an encrypted
16023 root partition, a swap file on the root partition, the X11 display
16024 server, GNOME and Xfce (users can choose which of these desktop
16025 environments to use at the log-in screen by pressing @kbd{F1}), network
16026 management, power management, and more, would look like this:
16029 @include os-config-desktop.texi
16032 A graphical system with a choice of lightweight window managers
16033 instead of full-blown desktop environments would look like this:
16036 @include os-config-lightweight-desktop.texi
16039 This example refers to the @file{/boot/efi} file system by its UUID,
16040 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
16041 as returned by the @command{blkid} command.
16043 @xref{Desktop Services}, for the exact list of services provided by
16044 @code{%desktop-services}. @xref{X.509 Certificates}, for background
16045 information about the @code{nss-certs} package that is used here.
16047 Again, @code{%desktop-services} is just a list of service objects. If
16048 you want to remove services from there, you can do so using the
16049 procedures for list filtering (@pxref{SRFI-1 Filtering and
16050 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
16051 following expression returns a list that contains all the services in
16052 @code{%desktop-services} minus the Avahi service:
16055 (remove (lambda (service)
16056 (eq? (service-kind service) avahi-service-type))
16060 Alternatively, the @code{modify-services} macro can be used:
16063 (modify-services %desktop-services
16064 (delete avahi-service-type))
16068 @unnumberedsubsec Instantiating the System
16070 Assuming the @code{operating-system} declaration
16071 is stored in the @file{my-system-config.scm}
16072 file, the @command{guix system reconfigure my-system-config.scm} command
16073 instantiates that configuration, and makes it the default GRUB boot
16074 entry (@pxref{Invoking guix system}).
16077 We recommend that you keep this @file{my-system-config.scm} file safe
16078 and under version control to easily track changes to your configuration.
16081 The normal way to change the system configuration is by updating this
16082 file and re-running @command{guix system reconfigure}. One should never
16083 have to touch files in @file{/etc} or to run commands that modify the
16084 system state such as @command{useradd} or @command{grub-install}. In
16085 fact, you must avoid that since that would not only void your warranty
16086 but also prevent you from rolling back to previous versions of your
16087 system, should you ever need to.
16089 @cindex roll-back, of the operating system
16090 Speaking of roll-back, each time you run @command{guix system
16091 reconfigure}, a new @dfn{generation} of the system is created---without
16092 modifying or deleting previous generations. Old system generations get
16093 an entry in the bootloader boot menu, allowing you to boot them in case
16094 something went wrong with the latest generation. Reassuring, no? The
16095 @command{guix system list-generations} command lists the system
16096 generations available on disk. It is also possible to roll back the
16097 system via the commands @command{guix system roll-back} and
16098 @command{guix system switch-generation}.
16100 Although the @command{guix system reconfigure} command will not modify
16101 previous generations, you must take care when the current generation is not
16102 the latest (e.g., after invoking @command{guix system roll-back}), since
16103 the operation might overwrite a later generation (@pxref{Invoking guix
16106 @unnumberedsubsec The Programming Interface
16108 At the Scheme level, the bulk of an @code{operating-system} declaration
16109 is instantiated with the following monadic procedure (@pxref{The Store
16112 @deffn {Monadic Procedure} operating-system-derivation os
16113 Return a derivation that builds @var{os}, an @code{operating-system}
16114 object (@pxref{Derivations}).
16116 The output of the derivation is a single directory that refers to all
16117 the packages, configuration files, and other supporting files needed to
16118 instantiate @var{os}.
16121 This procedure is provided by the @code{(gnu system)} module. Along
16122 with @code{(gnu services)} (@pxref{Services}), this module contains the
16123 guts of Guix System. Make sure to visit it!
16126 @node operating-system Reference
16127 @section @code{operating-system} Reference
16129 This section summarizes all the options available in
16130 @code{operating-system} declarations (@pxref{Using the Configuration
16133 @deftp {Data Type} operating-system
16134 This is the data type representing an operating system configuration.
16135 By that, we mean all the global system configuration, not per-user
16136 configuration (@pxref{Using the Configuration System}).
16139 @item @code{kernel} (default: @code{linux-libre})
16140 The package object of the operating system kernel to
16141 use@footnote{Currently only the Linux-libre kernel is fully supported.
16142 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
16143 available when building a virtual machine disk image.}.
16146 @item @code{hurd} (default: @code{#f})
16147 The package object of the Hurd to be started by the kernel. When this
16148 field is set, produce a GNU/Hurd operating system. In that case,
16149 @code{kernel} must also be set to the @code{gnumach} package---the
16150 microkernel the Hurd runs on.
16153 This feature is experimental and only supported for disk images.
16156 @item @code{kernel-loadable-modules} (default: '())
16157 A list of objects (usually packages) to collect loadable kernel modules
16158 from--e.g. @code{(list ddcci-driver-linux)}.
16160 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
16161 List of strings or gexps representing additional arguments to pass on
16162 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
16164 @item @code{bootloader}
16165 The system bootloader configuration object. @xref{Bootloader Configuration}.
16168 This is the label (a string) as it appears in the bootloader's menu entry.
16169 The default label includes the kernel name and version.
16171 @item @code{keyboard-layout} (default: @code{#f})
16172 This field specifies the keyboard layout to use in the console. It can be
16173 either @code{#f}, in which case the default keyboard layout is used (usually
16174 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
16175 for more information.
16177 This keyboard layout is in effect as soon as the kernel has booted. For
16178 instance, it is the keyboard layout in effect when you type a passphrase if
16179 your root file system is on a @code{luks-device-mapping} mapped device
16180 (@pxref{Mapped Devices}).
16183 This does @emph{not} specify the keyboard layout used by the bootloader, nor
16184 that used by the graphical display server. @xref{Bootloader Configuration},
16185 for information on how to specify the bootloader's keyboard layout. @xref{X
16186 Window}, for information on how to specify the keyboard layout used by the X
16190 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
16192 @cindex initial RAM disk
16193 The list of Linux kernel modules that need to be available in the
16194 initial RAM disk. @xref{Initial RAM Disk}.
16196 @item @code{initrd} (default: @code{base-initrd})
16197 A procedure that returns an initial RAM disk for the Linux
16198 kernel. This field is provided to support low-level customization and
16199 should rarely be needed for casual use. @xref{Initial RAM Disk}.
16201 @item @code{firmware} (default: @code{%base-firmware})
16203 List of firmware packages loadable by the operating system kernel.
16205 The default includes firmware needed for Atheros- and Broadcom-based
16206 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
16207 respectively). @xref{Hardware Considerations}, for more info on
16208 supported hardware.
16210 @item @code{host-name}
16213 @item @code{hosts-file}
16215 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
16216 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
16217 Reference Manual}). The default is a file with entries for
16218 @code{localhost} and @var{host-name}.
16220 @item @code{mapped-devices} (default: @code{'()})
16221 A list of mapped devices. @xref{Mapped Devices}.
16223 @item @code{file-systems}
16224 A list of file systems. @xref{File Systems}.
16226 @item @code{swap-devices} (default: @code{'()})
16227 @cindex swap devices
16228 A list of swap spaces. @xref{Swap Space}.
16230 @item @code{users} (default: @code{%base-user-accounts})
16231 @itemx @code{groups} (default: @code{%base-groups})
16232 List of user accounts and groups. @xref{User Accounts}.
16234 If the @code{users} list lacks a user account with UID@tie{}0, a
16235 ``root'' account with UID@tie{}0 is automatically added.
16237 @item @code{skeletons} (default: @code{(default-skeletons)})
16238 A list of target file name/file-like object tuples (@pxref{G-Expressions,
16239 file-like objects}). These are the skeleton files that will be added to
16240 the home directory of newly-created user accounts.
16242 For instance, a valid value may look like this:
16245 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
16246 (".guile" ,(plain-file "guile"
16247 "(use-modules (ice-9 readline))
16248 (activate-readline)")))
16251 @item @code{issue} (default: @code{%default-issue})
16252 A string denoting the contents of the @file{/etc/issue} file, which is
16253 displayed when users log in on a text console.
16255 @item @code{packages} (default: @code{%base-packages})
16256 A list of packages to be installed in the global profile, which is accessible
16257 at @file{/run/current-system/profile}. Each element is either a package
16258 variable or a package/output tuple. Here's a simple example of both:
16261 (cons* git ; the default "out" output
16262 (list git "send-email") ; another output of git
16263 %base-packages) ; the default set
16266 The default set includes core utilities and it is good practice to
16267 install non-core utilities in user profiles (@pxref{Invoking guix
16270 @item @code{timezone}
16271 A timezone identifying string---e.g., @code{"Europe/Paris"}.
16273 You can run the @command{tzselect} command to find out which timezone
16274 string corresponds to your region. Choosing an invalid timezone name
16275 causes @command{guix system} to fail.
16277 @item @code{locale} (default: @code{"en_US.utf8"})
16278 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
16279 Library Reference Manual}). @xref{Locales}, for more information.
16281 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
16282 The list of locale definitions to be compiled and that may be used at
16283 run time. @xref{Locales}.
16285 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
16286 The list of GNU@tie{}libc packages whose locale data and tools are used
16287 to build the locale definitions. @xref{Locales}, for compatibility
16288 considerations that justify this option.
16290 @item @code{name-service-switch} (default: @code{%default-nss})
16291 Configuration of the libc name service switch (NSS)---a
16292 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
16295 @item @code{services} (default: @code{%base-services})
16296 A list of service objects denoting system services. @xref{Services}.
16298 @cindex essential services
16299 @item @code{essential-services} (default: ...)
16300 The list of ``essential services''---i.e., things like instances of
16301 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
16302 Reference}), which are derived from the operating system definition itself.
16303 As a user you should @emph{never} need to touch this field.
16305 @item @code{pam-services} (default: @code{(base-pam-services)})
16307 @cindex pluggable authentication modules
16308 Linux @dfn{pluggable authentication module} (PAM) services.
16309 @c FIXME: Add xref to PAM services section.
16311 @item @code{setuid-programs} (default: @code{%setuid-programs})
16312 List of @code{<setuid-program>}. @xref{Setuid Programs}, for more
16315 @item @code{sudoers-file} (default: @code{%sudoers-specification})
16316 @cindex sudoers file
16317 The contents of the @file{/etc/sudoers} file as a file-like object
16318 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
16320 This file specifies which users can use the @command{sudo} command, what
16321 they are allowed to do, and what privileges they may gain. The default
16322 is that only @code{root} and members of the @code{wheel} group may use
16327 @deffn {Scheme Syntax} this-operating-system
16328 When used in the @emph{lexical scope} of an operating system field definition,
16329 this identifier resolves to the operating system being defined.
16331 The example below shows how to refer to the operating system being defined in
16332 the definition of the @code{label} field:
16335 (use-modules (gnu) (guix))
16339 (label (package-full-name
16340 (operating-system-kernel this-operating-system))))
16343 It is an error to refer to @code{this-operating-system} outside an operating
16350 @section File Systems
16352 The list of file systems to be mounted is specified in the
16353 @code{file-systems} field of the operating system declaration
16354 (@pxref{Using the Configuration System}). Each file system is declared
16355 using the @code{file-system} form, like this:
16359 (mount-point "/home")
16360 (device "/dev/sda3")
16364 As usual, some of the fields are mandatory---those shown in the example
16365 above---while others can be omitted. These are described below.
16367 @deftp {Data Type} file-system
16368 Objects of this type represent file systems to be mounted. They
16369 contain the following members:
16373 This is a string specifying the type of the file system---e.g.,
16376 @item @code{mount-point}
16377 This designates the place where the file system is to be mounted.
16379 @item @code{device}
16380 This names the ``source'' of the file system. It can be one of three
16381 things: a file system label, a file system UUID, or the name of a
16382 @file{/dev} node. Labels and UUIDs offer a way to refer to file
16383 systems without having to hard-code their actual device
16384 name@footnote{Note that, while it is tempting to use
16385 @file{/dev/disk/by-uuid} and similar device names to achieve the same
16386 result, this is not recommended: These special device nodes are created
16387 by the udev daemon and may be unavailable at the time the device is
16390 @findex file-system-label
16391 File system labels are created using the @code{file-system-label}
16392 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
16393 plain strings. Here's an example of a file system referred to by its
16394 label, as shown by the @command{e2label} command:
16398 (mount-point "/home")
16400 (device (file-system-label "my-home")))
16404 UUIDs are converted from their string representation (as shown by the
16405 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
16406 @code{uuid} form expects 16-byte UUIDs as defined in
16407 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
16408 form of UUID used by the ext2 family of file systems and others, but it
16409 is different from ``UUIDs'' found in FAT file systems, for instance.},
16414 (mount-point "/home")
16416 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16419 When the source of a file system is a mapped device (@pxref{Mapped
16420 Devices}), its @code{device} field @emph{must} refer to the mapped
16421 device name---e.g., @file{"/dev/mapper/root-partition"}.
16422 This is required so that
16423 the system knows that mounting the file system depends on having the
16424 corresponding device mapping established.
16426 @item @code{flags} (default: @code{'()})
16427 This is a list of symbols denoting mount flags. Recognized flags
16428 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
16429 access to special files), @code{no-suid} (ignore setuid and setgid
16430 bits), @code{no-atime} (do not update file access times),
16431 @code{strict-atime} (update file access time), @code{lazy-time} (only
16432 update time on the in-memory version of the file inode),
16433 @code{no-exec} (disallow program execution), and @code{shared} (make the
16435 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
16436 Manual}, for more information on these flags.
16438 @item @code{options} (default: @code{#f})
16439 This is either @code{#f}, or a string denoting mount options passed to
16440 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
16441 Library Reference Manual}, for details.
16443 Run @command{man 8 mount} for options for various file systems, but
16444 beware that what it lists as file-system-independent ``mount options'' are
16445 in fact flags, and belong in the @code{flags} field described above.
16447 The @code{file-system-options->alist} and @code{alist->file-system-options}
16448 procedures from @code{(gnu system file-systems)} can be used to convert
16449 file system options given as an association list to the string
16450 representation, and vice-versa.
16452 @item @code{mount?} (default: @code{#t})
16453 This value indicates whether to automatically mount the file system when
16454 the system is brought up. When set to @code{#f}, the file system gets
16455 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
16456 is not automatically mounted.
16458 @item @code{needed-for-boot?} (default: @code{#f})
16459 This Boolean value indicates whether the file system is needed when
16460 booting. If that is true, then the file system is mounted when the
16461 initial RAM disk (initrd) is loaded. This is always the case, for
16462 instance, for the root file system.
16464 @item @code{check?} (default: @code{#t})
16465 This Boolean indicates whether the file system should be checked for
16466 errors before being mounted. How and when this happens can be further
16467 adjusted with the following options.
16469 @item @code{skip-check-if-clean?} (default: @code{#t})
16470 When true, this Boolean indicates that a file system check triggered
16471 by @code{check?} may exit early if the file system is marked as
16472 ``clean'', meaning that it was previously correctly unmounted and
16473 should not contain errors.
16475 Setting this to false will always force a full consistency check when
16476 @code{check?} is true. This may take a very long time and is not
16477 recommended on healthy systems---in fact, it may reduce reliability!
16479 Conversely, some primitive file systems like @code{fat} do not keep
16480 track of clean shutdowns and will perform a full scan regardless of the
16481 value of this option.
16483 @item @code{repair} (default: @code{'preen})
16484 When @code{check?} finds errors, it can (try to) repair them and
16485 continue booting. This option controls when and how to do so.
16487 If false, try not to modify the file system at all. Checking certain
16488 file systems like @code{jfs} may still write to the device to replay
16489 the journal. No repairs will be attempted.
16491 If @code{#t}, try to repair any errors found and assume ``yes'' to
16492 all questions. This will fix the most errors, but may be risky.
16494 If @code{'preen}, repair only errors that are safe to fix without
16495 human interaction. What that means is left up to the developers of
16496 each file system and may be equivalent to ``none'' or ``all''.
16498 @item @code{create-mount-point?} (default: @code{#f})
16499 When true, the mount point is created if it does not exist yet.
16501 @item @code{mount-may-fail?} (default: @code{#f})
16502 When true, this indicates that mounting this file system can fail but
16503 that should not be considered an error. This is useful in unusual
16504 cases; an example of this is @code{efivarfs}, a file system that can
16505 only be mounted on EFI/UEFI systems.
16507 @item @code{dependencies} (default: @code{'()})
16508 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
16509 representing file systems that must be mounted or mapped devices that
16510 must be opened before (and unmounted or closed after) this one.
16512 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
16513 a dependency of @file{/sys/fs/cgroup/cpu} and
16514 @file{/sys/fs/cgroup/memory}.
16516 Another example is a file system that depends on a mapped device, for
16517 example for an encrypted partition (@pxref{Mapped Devices}).
16521 @deffn {Scheme Procedure} file-system-label @var{str}
16522 This procedure returns an opaque file system label from @var{str}, a
16526 (file-system-label "home")
16527 @result{} #<file-system-label "home">
16530 File system labels are used to refer to file systems by label rather
16531 than by device name. See above for examples.
16534 The @code{(gnu system file-systems)} exports the following useful
16537 @defvr {Scheme Variable} %base-file-systems
16538 These are essential file systems that are required on normal systems,
16539 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
16540 below). Operating system declarations should always contain at least
16544 @defvr {Scheme Variable} %pseudo-terminal-file-system
16545 This is the file system to be mounted as @file{/dev/pts}. It supports
16546 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
16547 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
16548 Manual}). Pseudo-terminals are used by terminal emulators such as
16552 @defvr {Scheme Variable} %shared-memory-file-system
16553 This file system is mounted as @file{/dev/shm} and is used to support
16554 memory sharing across processes (@pxref{Memory-mapped I/O,
16555 @code{shm_open},, libc, The GNU C Library Reference Manual}).
16558 @defvr {Scheme Variable} %immutable-store
16559 This file system performs a read-only ``bind mount'' of
16560 @file{/gnu/store}, making it read-only for all the users including
16561 @code{root}. This prevents against accidental modification by software
16562 running as @code{root} or by system administrators.
16564 The daemon itself is still able to write to the store: it remounts it
16565 read-write in its own ``name space.''
16568 @defvr {Scheme Variable} %binary-format-file-system
16569 The @code{binfmt_misc} file system, which allows handling of arbitrary
16570 executable file types to be delegated to user space. This requires the
16571 @code{binfmt.ko} kernel module to be loaded.
16574 @defvr {Scheme Variable} %fuse-control-file-system
16575 The @code{fusectl} file system, which allows unprivileged users to mount
16576 and unmount user-space FUSE file systems. This requires the
16577 @code{fuse.ko} kernel module to be loaded.
16580 The @code{(gnu system uuid)} module provides tools to deal with file
16581 system ``unique identifiers'' (UUIDs).
16583 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
16584 Return an opaque UUID (unique identifier) object of the given @var{type}
16585 (a symbol) by parsing @var{str} (a string):
16588 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
16589 @result{} #<<uuid> type: dce bv: @dots{}>
16591 (uuid "1234-ABCD" 'fat)
16592 @result{} #<<uuid> type: fat bv: @dots{}>
16595 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
16596 @code{ntfs}, or one of the commonly found synonyms for these.
16598 UUIDs are another way to unambiguously refer to file systems in
16599 operating system configuration. See the examples above.
16603 @node Btrfs file system
16604 @subsection Btrfs file system
16606 The Btrfs has special features, such as subvolumes, that merit being
16607 explained in more details. The following section attempts to cover
16608 basic as well as complex uses of a Btrfs file system with the Guix
16611 In its simplest usage, a Btrfs file system can be described, for
16616 (mount-point "/home")
16618 (device (file-system-label "my-home")))
16621 The example below is more complex, as it makes use of a Btrfs
16622 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
16623 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
16624 dependency on @code{mapped-devices}):
16628 (device (file-system-label "my-btrfs-pool"))
16631 (options "subvol=rootfs")
16632 (dependencies mapped-devices))
16635 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
16636 top level during the early boot, and rely on their configuration to
16637 refer to the correct subvolume path within that top level. The
16638 bootloaders operating in this way typically produce their configuration
16639 on a running system where the Btrfs partitions are already mounted and
16640 where the subvolume information is readily available. As an example,
16641 @command{grub-mkconfig}, the configuration generator command shipped
16642 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
16643 path of a subvolume.
16645 The Guix System produces a bootloader configuration using the operating
16646 system configuration as its sole input; it is therefore necessary to
16647 extract the subvolume name on which @file{/gnu/store} lives (if any)
16648 from that operating system configuration. To better illustrate,
16649 consider a subvolume named 'rootfs' which contains the root file system
16650 data. In such situation, the GRUB bootloader would only see the top
16651 level of the root Btrfs partition, e.g.:
16655 ├── rootfs (subvolume directory)
16656 ├── gnu (normal directory)
16657 ├── store (normal directory)
16661 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
16662 of the kernel, initrd binaries and any other files referred to in the
16663 GRUB configuration that must be found during the early boot.
16665 The next example shows a nested hierarchy of subvolumes and
16670 ├── rootfs (subvolume)
16671 ├── gnu (normal directory)
16672 ├── store (subvolume)
16676 This scenario would work without mounting the 'store' subvolume.
16677 Mounting 'rootfs' is sufficient, since the subvolume name matches its
16678 intended mount point in the file system hierarchy. Alternatively, the
16679 'store' subvolume could be referred to by setting the @code{subvol}
16680 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
16682 Finally, a more contrived example of nested subvolumes:
16686 ├── root-snapshots (subvolume)
16687 ├── root-current (subvolume)
16688 ├── guix-store (subvolume)
16692 Here, the 'guix-store' subvolume doesn't match its intended mount point,
16693 so it is necessary to mount it. The subvolume must be fully specified,
16694 by passing its file name to the @code{subvol} option. To illustrate,
16695 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
16696 a file system declaration such as:
16700 (device (file-system-label "btrfs-pool-1"))
16701 (mount-point "/gnu/store")
16703 (options "subvol=root-snapshots/root-current/guix-store,\
16704 compress-force=zstd,space_cache=v2"))
16707 @node Mapped Devices
16708 @section Mapped Devices
16710 @cindex device mapping
16711 @cindex mapped devices
16712 The Linux kernel has a notion of @dfn{device mapping}: a block device,
16713 such as a hard disk partition, can be @dfn{mapped} into another device,
16714 usually in @code{/dev/mapper/},
16715 with additional processing over the data that flows through
16716 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
16717 concept of a ``mapped device'' and that of a file system: both boil down
16718 to @emph{translating} input/output operations made on a file to
16719 operations on its backing store. Thus, the Hurd implements mapped
16720 devices, like file systems, using the generic @dfn{translator} mechanism
16721 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
16722 typical example is encryption device mapping: all writes to the mapped
16723 device are encrypted, and all reads are deciphered, transparently.
16724 Guix extends this notion by considering any device or set of devices that
16725 are @dfn{transformed} in some way to create a new device; for instance,
16726 RAID devices are obtained by @dfn{assembling} several other devices, such
16727 as hard disks or partitions, into a new one that behaves as one partition.
16729 Mapped devices are declared using the @code{mapped-device} form,
16730 defined as follows; for examples, see below.
16732 @deftp {Data Type} mapped-device
16733 Objects of this type represent device mappings that will be made when
16734 the system boots up.
16738 This is either a string specifying the name of the block device to be mapped,
16739 such as @code{"/dev/sda3"}, or a list of such strings when several devices
16740 need to be assembled for creating a new one. In case of LVM this is a
16741 string specifying name of the volume group to be mapped.
16744 This string specifies the name of the resulting mapped device. For
16745 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
16746 specifying @code{"my-partition"} leads to the creation of
16747 the @code{"/dev/mapper/my-partition"} device.
16748 For RAID devices of type @code{raid-device-mapping}, the full device name
16749 such as @code{"/dev/md0"} needs to be given.
16750 LVM logical volumes of type @code{lvm-device-mapping} need to
16751 be specified as @code{"VGNAME-LVNAME"}.
16754 This list of strings specifies names of the resulting mapped devices in case
16755 there are several. The format is identical to @var{target}.
16758 This must be a @code{mapped-device-kind} object, which specifies how
16759 @var{source} is mapped to @var{target}.
16763 @defvr {Scheme Variable} luks-device-mapping
16764 This defines LUKS block device encryption using the @command{cryptsetup}
16765 command from the package with the same name. It relies on the
16766 @code{dm-crypt} Linux kernel module.
16769 @defvr {Scheme Variable} raid-device-mapping
16770 This defines a RAID device, which is assembled using the @code{mdadm}
16771 command from the package with the same name. It requires a Linux kernel
16772 module for the appropriate RAID level to be loaded, such as @code{raid456}
16773 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
16776 @cindex LVM, logical volume manager
16777 @defvr {Scheme Variable} lvm-device-mapping
16778 This defines one or more logical volumes for the Linux
16779 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
16780 The volume group is activated by the @command{vgchange} command from the
16781 @code{lvm2} package.
16784 @cindex disk encryption
16786 The following example specifies a mapping from @file{/dev/sda3} to
16787 @file{/dev/mapper/home} using LUKS---the
16788 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
16789 standard mechanism for disk encryption.
16790 The @file{/dev/mapper/home}
16791 device can then be used as the @code{device} of a @code{file-system}
16792 declaration (@pxref{File Systems}).
16796 (source "/dev/sda3")
16798 (type luks-device-mapping))
16801 Alternatively, to become independent of device numbering, one may obtain
16802 the LUKS UUID (@dfn{unique identifier}) of the source device by a
16806 cryptsetup luksUUID /dev/sda3
16809 and use it as follows:
16813 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
16815 (type luks-device-mapping))
16818 @cindex swap encryption
16819 It is also desirable to encrypt swap space, since swap space may contain
16820 sensitive data. One way to accomplish that is to use a swap file in a
16821 file system on a device mapped via LUKS encryption. In this way, the
16822 swap file is encrypted because the entire device is encrypted.
16823 @xref{Swap Space}, or @xref{Preparing for Installation,,Disk
16824 Partitioning}, for an example.
16826 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
16827 may be declared as follows:
16831 (source (list "/dev/sda1" "/dev/sdb1"))
16832 (target "/dev/md0")
16833 (type raid-device-mapping))
16836 The @file{/dev/md0} device can then be used as the @code{device} of a
16837 @code{file-system} declaration (@pxref{File Systems}).
16838 Note that the RAID level need not be given; it is chosen during the
16839 initial creation and formatting of the RAID device and is determined
16840 automatically later.
16842 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
16843 be declared as follows:
16848 (targets (list "vg0-alpha" "vg0-beta"))
16849 (type lvm-device-mapping))
16852 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
16853 then be used as the @code{device} of a @code{file-system} declaration
16854 (@pxref{File Systems}).
16857 @section Swap Space
16860 Swap space, as it is commonly called, is a disk area specifically
16861 designated for paging: the process in charge of memory management
16862 (the Linux kernel or Hurd's default pager) can decide that some memory
16863 pages stored in RAM which belong to a running program but are unused
16864 should be stored on disk instead. It unloads those from the RAM,
16865 freeing up precious fast memory, and writes them to the swap space. If
16866 the program tries to access that very page, the memory management
16867 process loads it back into memory for the program to use.
16869 A common misconception about swap is that it is only useful when small
16870 amounts of RAM are available to the system. However, it should be noted
16871 that kernels often use all available RAM for disk access caching to make
16872 I/O faster, and thus paging out unused portions of program memory will
16873 expand the RAM available for such caching.
16875 For a more detailed description of how memory is managed from the
16876 viewpoint of a monolithic kernel, @xref{Memory
16877 Concepts,,, libc, The GNU C Library Reference Manual}.
16879 The Linux kernel has support for swap partitions and swap files: the
16880 former uses a whole disk partition for paging, whereas the second uses a
16881 file on a file system for that (the file system driver needs to support
16882 it). On a comparable setup, both have the same performance, so one
16883 should consider ease of use when deciding between them. Partitions are
16884 ``simpler'' and do not need file system support, but need to be
16885 allocated at disk formatting time (logical volumes notwithstanding),
16886 whereas files can be allocated and deallocated at any time.
16888 Note that swap space is not zeroed on shutdown, so sensitive data (such
16889 as passwords) may linger on it if it was paged out. As such, you should
16890 consider having your swap reside on an encrypted device (@pxref{Mapped
16893 @deftp {Data Type} swap-space
16894 Objects of this type represent swap spaces. They contain the following
16898 @item @code{target}
16899 The device or file to use, either a UUID, a @code{file-system-label} or
16900 a string, as in the definition of a @code{file-system} (@pxref{File
16903 @item @code{dependencies} (default: @code{'()})
16904 A list of @code{file-system} or @code{mapped-device} objects, upon which
16905 the availability of the space depends. Note that just like for
16906 @code{file-system} objects, dependencies which are needed for boot and
16907 mounted in early userspace are not managed by the Shepherd, and so
16908 automatically filtered out for you.
16910 @item @code{priority} (default: @code{#f})
16911 Only supported by the Linux kernel. Either @code{#f} to disable swap
16912 priority, or an integer between 0 and 32767. The kernel will first use
16913 swap spaces of higher priority when paging, and use same priority spaces
16914 on a round-robin basis. The kernel will use swap spaces without a set
16915 priority after prioritized spaces, and in the order that they appeared in
16918 @item @code{discard?} (default: @code{#f})
16919 Only supported by the Linux kernel. When true, the kernel will notify
16920 the disk controller of discarded pages, for example with the TRIM
16921 operation on Solid State Drives.
16926 Here are some examples:
16929 (swap-space (target (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16932 Use the swap partition with the given UUID@. You can learn the UUID of a
16933 Linux swap partition by running @command{swaplabel @var{device}}, where
16934 @var{device} is the @file{/dev} file name of that partition.
16938 (target (file-system-label "swap"))
16939 (dependencies mapped-devices))
16942 Use the partition with label @code{swap}, which can be found after all
16943 the @var{mapped-devices} mapped devices have been opened. Again, the
16944 @command{swaplabel} command allows you to view and change the label of a
16945 Linux swap partition.
16947 Here's a more involved example with the corresponding @code{file-systems} part
16948 of an @code{operating-system} declaration.
16953 (device (file-system-label "root"))
16957 (device (file-system-label "btrfs"))
16958 (mount-point "/btrfs")
16964 (target "/btrfs/swapfile")
16965 (dependencies (filter (file-system-mount-point-predicate "/btrfs")
16969 Use the file @file{/btrfs/swapfile} as swap space, which depends on the
16970 file system mounted at @file{/btrfs}. Note how we use Guile's filter to
16971 select the file system in an elegant fashion!
16973 @node User Accounts
16974 @section User Accounts
16978 @cindex user accounts
16979 User accounts and groups are entirely managed through the
16980 @code{operating-system} declaration. They are specified with the
16981 @code{user-account} and @code{user-group} forms:
16987 (supplementary-groups '("wheel" ;allow use of sudo, etc.
16988 "audio" ;sound card
16989 "video" ;video devices such as webcams
16990 "cdrom")) ;the good ol' CD-ROM
16991 (comment "Bob's sister"))
16994 Here's a user account that uses a different shell and a custom home
16995 directory (the default would be @file{"/home/bob"}):
17001 (comment "Alice's bro")
17002 (shell (file-append zsh "/bin/zsh"))
17003 (home-directory "/home/robert"))
17006 When booting or upon completion of @command{guix system reconfigure},
17007 the system ensures that only the user accounts and groups specified in
17008 the @code{operating-system} declaration exist, and with the specified
17009 properties. Thus, account or group creations or modifications made by
17010 directly invoking commands such as @command{useradd} are lost upon
17011 reconfiguration or reboot. This ensures that the system remains exactly
17014 @deftp {Data Type} user-account
17015 Objects of this type represent user accounts. The following members may
17020 The name of the user account.
17024 This is the name (a string) or identifier (a number) of the user group
17025 this account belongs to.
17027 @item @code{supplementary-groups} (default: @code{'()})
17028 Optionally, this can be defined as a list of group names that this
17029 account belongs to.
17031 @item @code{uid} (default: @code{#f})
17032 This is the user ID for this account (a number), or @code{#f}. In the
17033 latter case, a number is automatically chosen by the system when the
17034 account is created.
17036 @item @code{comment} (default: @code{""})
17037 A comment about the account, such as the account owner's full name.
17039 Note that, for non-system accounts, users are free to change their real
17040 name as it appears in @file{/etc/passwd} using the @command{chfn}
17041 command. When they do, their choice prevails over the system
17042 administrator's choice; reconfiguring does @emph{not} change their name.
17044 @item @code{home-directory}
17045 This is the name of the home directory for the account.
17047 @item @code{create-home-directory?} (default: @code{#t})
17048 Indicates whether the home directory of this account should be created
17049 if it does not exist yet.
17051 @item @code{shell} (default: Bash)
17052 This is a G-expression denoting the file name of a program to be used as
17053 the shell (@pxref{G-Expressions}). For example, you would refer to the
17054 Bash executable like this:
17057 (file-append bash "/bin/bash")
17061 ... and to the Zsh executable like that:
17064 (file-append zsh "/bin/zsh")
17067 @item @code{system?} (default: @code{#f})
17068 This Boolean value indicates whether the account is a ``system''
17069 account. System accounts are sometimes treated specially; for instance,
17070 graphical login managers do not list them.
17072 @anchor{user-account-password}
17073 @cindex password, for user accounts
17074 @item @code{password} (default: @code{#f})
17075 You would normally leave this field to @code{#f}, initialize user
17076 passwords as @code{root} with the @command{passwd} command, and then let
17077 users change it with @command{passwd}. Passwords set with
17078 @command{passwd} are of course preserved across reboot and
17081 If you @emph{do} want to set an initial password for an account, then
17082 this field must contain the encrypted password, as a string. You can use the
17083 @code{crypt} procedure for this purpose:
17090 ;; Specify a SHA-512-hashed initial password.
17091 (password (crypt "InitialPassword!" "$6$abc")))
17095 The hash of this initial password will be available in a file in
17096 @file{/gnu/store}, readable by all the users, so this method must be used with
17100 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
17101 more information on password encryption, and @ref{Encryption,,, guile, GNU
17102 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
17108 User group declarations are even simpler:
17111 (user-group (name "students"))
17114 @deftp {Data Type} user-group
17115 This type is for, well, user groups. There are just a few fields:
17119 The name of the group.
17121 @item @code{id} (default: @code{#f})
17122 The group identifier (a number). If @code{#f}, a new number is
17123 automatically allocated when the group is created.
17125 @item @code{system?} (default: @code{#f})
17126 This Boolean value indicates whether the group is a ``system'' group.
17127 System groups have low numerical IDs.
17129 @item @code{password} (default: @code{#f})
17130 What, user groups can have a password? Well, apparently yes. Unless
17131 @code{#f}, this field specifies the password of the group.
17136 For convenience, a variable lists all the basic user groups one may
17139 @defvr {Scheme Variable} %base-groups
17140 This is the list of basic user groups that users and/or packages expect
17141 to be present on the system. This includes groups such as ``root'',
17142 ``wheel'', and ``users'', as well as groups used to control access to
17143 specific devices such as ``audio'', ``disk'', and ``cdrom''.
17146 @defvr {Scheme Variable} %base-user-accounts
17147 This is the list of basic system accounts that programs may expect to
17148 find on a GNU/Linux system, such as the ``nobody'' account.
17150 Note that the ``root'' account is not included here. It is a
17151 special-case and is automatically added whether or not it is specified.
17154 @node Keyboard Layout
17155 @section Keyboard Layout
17157 @cindex keyboard layout
17159 To specify what each key of your keyboard does, you need to tell the operating
17160 system what @dfn{keyboard layout} you want to use. The default, when nothing
17161 is specified, is the US English QWERTY layout for 105-key PC keyboards.
17162 However, German speakers will usually prefer the German QWERTZ layout, French
17163 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
17164 or bépo, and they might even want to further customize the effect of some of
17165 the keys. This section explains how to get that done.
17167 @cindex keyboard layout, definition
17168 There are three components that will want to know about your keyboard layout:
17172 The @emph{bootloader} may want to know what keyboard layout you want to use
17173 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
17174 you want, for instance, to make sure that you can type the passphrase of your
17175 encrypted root partition using the right layout.
17178 The @emph{operating system kernel}, Linux, will need that so that the console
17179 is properly configured (@pxref{operating-system Reference,
17180 @code{keyboard-layout}}).
17183 The @emph{graphical display server}, usually Xorg, also has its own idea of
17184 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
17187 Guix allows you to configure all three separately but, fortunately, it allows
17188 you to share the same keyboard layout for all three components.
17190 @cindex XKB, keyboard layouts
17191 Keyboard layouts are represented by records created by the
17192 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
17193 the X Keyboard extension (XKB), each layout has four attributes: a name (often
17194 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
17195 optional variant name, an optional keyboard model name, and a possibly empty
17196 list of additional options. In most cases the layout name is all you care
17199 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
17200 [#:model] [#:options '()]
17201 Return a new keyboard layout with the given @var{name} and @var{variant}.
17203 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
17204 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
17205 @code{xkeyboard-config} package for valid options.
17208 Here are a few examples:
17211 ;; The German QWERTZ layout. Here we assume a standard
17212 ;; "pc105" keyboard model.
17213 (keyboard-layout "de")
17215 ;; The bépo variant of the French layout.
17216 (keyboard-layout "fr" "bepo")
17218 ;; The Catalan layout.
17219 (keyboard-layout "es" "cat")
17221 ;; Arabic layout with "Alt-Shift" to switch to US layout.
17222 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
17224 ;; The Latin American Spanish layout. In addition, the
17225 ;; "Caps Lock" key is used as an additional "Ctrl" key,
17226 ;; and the "Menu" key is used as a "Compose" key to enter
17227 ;; accented letters.
17228 (keyboard-layout "latam"
17229 #:options '("ctrl:nocaps" "compose:menu"))
17231 ;; The Russian layout for a ThinkPad keyboard.
17232 (keyboard-layout "ru" #:model "thinkpad")
17234 ;; The "US international" layout, which is the US layout plus
17235 ;; dead keys to enter accented characters. This is for an
17236 ;; Apple MacBook keyboard.
17237 (keyboard-layout "us" "intl" #:model "macbook78")
17240 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
17241 for a complete list of supported layouts, variants, and models.
17243 @cindex keyboard layout, configuration
17244 Let's say you want your system to use the Turkish keyboard layout throughout
17245 your system---bootloader, console, and Xorg. Here's what your system
17246 configuration would look like:
17248 @findex set-xorg-configuration
17250 ;; Using the Turkish layout for the bootloader, the console,
17255 (keyboard-layout (keyboard-layout "tr")) ;for the console
17256 (bootloader (bootloader-configuration
17257 (bootloader grub-efi-bootloader)
17258 (targets '("/boot/efi"))
17259 (keyboard-layout keyboard-layout))) ;for GRUB
17260 (services (cons (set-xorg-configuration
17261 (xorg-configuration ;for Xorg
17262 (keyboard-layout keyboard-layout)))
17263 %desktop-services)))
17266 In the example above, for GRUB and for Xorg, we just refer to the
17267 @code{keyboard-layout} field defined above, but we could just as well refer to
17268 a different layout. The @code{set-xorg-configuration} procedure communicates
17269 the desired Xorg configuration to the graphical log-in manager, by default
17272 We've discussed how to specify the @emph{default} keyboard layout of your
17273 system when it starts, but you can also adjust it at run time:
17277 If you're using GNOME, its settings panel has a ``Region & Language'' entry
17278 where you can select one or more keyboard layouts.
17281 Under Xorg, the @command{setxkbmap} command (from the same-named package)
17282 allows you to change the current layout. For example, this is how you would
17283 change the layout to US Dvorak:
17286 setxkbmap us dvorak
17290 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
17291 console. However, note that @code{loadkeys} does @emph{not} use the XKB
17292 keyboard layout categorization described above. The command below loads the
17293 French bépo layout:
17304 A @dfn{locale} defines cultural conventions for a particular language
17305 and region of the world (@pxref{Locales,,, libc, The GNU C Library
17306 Reference Manual}). Each locale has a name that typically has the form
17307 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
17308 @code{fr_LU.utf8} designates the locale for the French language, with
17309 cultural conventions from Luxembourg, and using the UTF-8 encoding.
17311 @cindex locale definition
17312 Usually, you will want to specify the default locale for the machine
17313 using the @code{locale} field of the @code{operating-system} declaration
17314 (@pxref{operating-system Reference, @code{locale}}).
17316 The selected locale is automatically added to the @dfn{locale
17317 definitions} known to the system if needed, with its codeset inferred
17318 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
17319 @code{UTF-8} codeset. Additional locale definitions can be specified in
17320 the @code{locale-definitions} slot of @code{operating-system}---this is
17321 useful, for instance, if the codeset could not be inferred from the
17322 locale name. The default set of locale definitions includes some widely
17323 used locales, but not all the available locales, in order to save space.
17325 For instance, to add the North Frisian locale for Germany, the value of
17329 (cons (locale-definition
17330 (name "fy_DE.utf8") (source "fy_DE"))
17331 %default-locale-definitions)
17334 Likewise, to save space, one might want @code{locale-definitions} to
17335 list only the locales that are actually used, as in:
17338 (list (locale-definition
17339 (name "ja_JP.eucjp") (source "ja_JP")
17340 (charset "EUC-JP")))
17344 The compiled locale definitions are available at
17345 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
17346 version, which is the default location where the GNU@tie{}libc provided
17347 by Guix looks for locale data. This can be overridden using the
17348 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
17349 @env{LOCPATH} and locale packages}).
17351 The @code{locale-definition} form is provided by the @code{(gnu system
17352 locale)} module. Details are given below.
17354 @deftp {Data Type} locale-definition
17355 This is the data type of a locale definition.
17360 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
17361 Reference Manual}, for more information on locale names.
17363 @item @code{source}
17364 The name of the source for that locale. This is typically the
17365 @code{@var{language}_@var{territory}} part of the locale name.
17367 @item @code{charset} (default: @code{"UTF-8"})
17368 The ``character set'' or ``code set'' for that locale,
17369 @uref{https://www.iana.org/assignments/character-sets, as defined by
17375 @defvr {Scheme Variable} %default-locale-definitions
17376 A list of commonly used UTF-8 locales, used as the default
17377 value of the @code{locale-definitions} field of @code{operating-system}
17380 @cindex locale name
17381 @cindex normalized codeset in locale names
17382 These locale definitions use the @dfn{normalized codeset} for the part
17383 that follows the dot in the name (@pxref{Using gettextized software,
17384 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
17385 instance it has @code{uk_UA.utf8} but @emph{not}, say,
17386 @code{uk_UA.UTF-8}.
17389 @subsection Locale Data Compatibility Considerations
17391 @cindex incompatibility, of locale data
17392 @code{operating-system} declarations provide a @code{locale-libcs} field
17393 to specify the GNU@tie{}libc packages that are used to compile locale
17394 declarations (@pxref{operating-system Reference}). ``Why would I
17395 care?'', you may ask. Well, it turns out that the binary format of
17396 locale data is occasionally incompatible from one libc version to
17399 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
17400 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
17401 For instance, a program linked against libc version 2.21 is unable to
17402 read locale data produced with libc 2.22; worse, that program
17403 @emph{aborts} instead of simply ignoring the incompatible locale
17404 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
17405 the incompatible locale data, which is already an improvement.}.
17406 Similarly, a program linked against libc 2.22 can read most, but not
17407 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
17408 data is incompatible); thus calls to @code{setlocale} may fail, but
17409 programs will not abort.
17411 The ``problem'' with Guix is that users have a lot of freedom: They can
17412 choose whether and when to upgrade software in their profiles, and might
17413 be using a libc version different from the one the system administrator
17414 used to build the system-wide locale data.
17416 Fortunately, unprivileged users can also install their own locale data
17417 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
17418 @env{GUIX_LOCPATH} and locale packages}).
17420 Still, it is best if the system-wide locale data at
17421 @file{/run/current-system/locale} is built for all the libc versions
17422 actually in use on the system, so that all the programs can access
17423 it---this is especially crucial on a multi-user system. To do that, the
17424 administrator can specify several libc packages in the
17425 @code{locale-libcs} field of @code{operating-system}:
17428 (use-package-modules base)
17432 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
17435 This example would lead to a system containing locale definitions for
17436 both libc 2.21 and the current version of libc in
17437 @file{/run/current-system/locale}.
17443 @cindex system services
17444 An important part of preparing an @code{operating-system} declaration is
17445 listing @dfn{system services} and their configuration (@pxref{Using the
17446 Configuration System}). System services are typically daemons launched
17447 when the system boots, or other actions needed at that time---e.g.,
17448 configuring network access.
17450 Guix has a broad definition of ``service'' (@pxref{Service
17451 Composition}), but many services are managed by the GNU@tie{}Shepherd
17452 (@pxref{Shepherd Services}). On a running system, the @command{herd}
17453 command allows you to list the available services, show their status,
17454 start and stop them, or do other specific operations (@pxref{Jump
17455 Start,,, shepherd, The GNU Shepherd Manual}). For example:
17461 The above command, run as @code{root}, lists the currently defined
17462 services. The @command{herd doc} command shows a synopsis of the given
17463 service and its associated actions:
17467 Run libc's name service cache daemon (nscd).
17469 # herd doc nscd action invalidate
17470 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
17473 The @command{start}, @command{stop}, and @command{restart} sub-commands
17474 have the effect you would expect. For instance, the commands below stop
17475 the nscd service and restart the Xorg display server:
17479 Service nscd has been stopped.
17480 # herd restart xorg-server
17481 Service xorg-server has been stopped.
17482 Service xorg-server has been started.
17485 The following sections document the available services, starting with
17486 the core services, that may be used in an @code{operating-system}
17490 * Base Services:: Essential system services.
17491 * Scheduled Job Execution:: The mcron service.
17492 * Log Rotation:: The rottlog service.
17493 * Networking Setup:: Setting up network interfaces.
17494 * Networking Services:: Firewall, SSH daemon, etc.
17495 * Unattended Upgrades:: Automated system upgrades.
17496 * X Window:: Graphical display.
17497 * Printing Services:: Local and remote printer support.
17498 * Desktop Services:: D-Bus and desktop services.
17499 * Sound Services:: ALSA and Pulseaudio services.
17500 * Database Services:: SQL databases, key-value stores, etc.
17501 * Mail Services:: IMAP, POP3, SMTP, and all that.
17502 * Messaging Services:: Messaging services.
17503 * Telephony Services:: Telephony services.
17504 * File-Sharing Services:: File-sharing services.
17505 * Monitoring Services:: Monitoring services.
17506 * Kerberos Services:: Kerberos services.
17507 * LDAP Services:: LDAP services.
17508 * Web Services:: Web servers.
17509 * Certificate Services:: TLS certificates via Let's Encrypt.
17510 * DNS Services:: DNS daemons.
17511 * VPN Services:: VPN daemons.
17512 * Network File System:: NFS related services.
17513 * Continuous Integration:: Cuirass and Laminar services.
17514 * Power Management Services:: Extending battery life.
17515 * Audio Services:: The MPD.
17516 * Virtualization Services:: Virtualization services.
17517 * Version Control Services:: Providing remote access to Git repositories.
17518 * Game Services:: Game servers.
17519 * PAM Mount Service:: Service to mount volumes when logging in.
17520 * Guix Services:: Services relating specifically to Guix.
17521 * Linux Services:: Services tied to the Linux kernel.
17522 * Hurd Services:: Services specific for a Hurd System.
17523 * Miscellaneous Services:: Other services.
17526 @node Base Services
17527 @subsection Base Services
17529 The @code{(gnu services base)} module provides definitions for the basic
17530 services that one expects from the system. The services exported by
17531 this module are listed below.
17533 @defvr {Scheme Variable} %base-services
17534 This variable contains a list of basic services (@pxref{Service Types
17535 and Services}, for more information on service objects) one would
17536 expect from the system: a login service (mingetty) on each tty, syslogd,
17537 the libc name service cache daemon (nscd), the udev device manager, and
17540 This is the default value of the @code{services} field of
17541 @code{operating-system} declarations. Usually, when customizing a
17542 system, you will want to append services to @code{%base-services}, like
17546 (append (list (service avahi-service-type)
17547 (service openssh-service-type))
17552 @defvr {Scheme Variable} special-files-service-type
17553 This is the service that sets up ``special files'' such as
17554 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
17556 The value associated with @code{special-files-service-type} services
17557 must be a list of tuples where the first element is the ``special file''
17558 and the second element is its target. By default it is:
17560 @cindex @file{/bin/sh}
17561 @cindex @file{sh}, in @file{/bin}
17563 `(("/bin/sh" ,(file-append bash "/bin/sh")))
17566 @cindex @file{/usr/bin/env}
17567 @cindex @file{env}, in @file{/usr/bin}
17568 If you want to add, say, @code{/usr/bin/env} to your system, you can
17572 `(("/bin/sh" ,(file-append bash "/bin/sh"))
17573 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
17576 Since this is part of @code{%base-services}, you can use
17577 @code{modify-services} to customize the set of special files
17578 (@pxref{Service Reference, @code{modify-services}}). But the simple way
17579 to add a special file is @i{via} the @code{extra-special-file} procedure
17583 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
17584 Use @var{target} as the ``special file'' @var{file}.
17586 For example, adding the following lines to the @code{services} field of
17587 your operating system declaration leads to a @file{/usr/bin/env}
17591 (extra-special-file "/usr/bin/env"
17592 (file-append coreutils "/bin/env"))
17596 @deffn {Scheme Procedure} host-name-service @var{name}
17597 Return a service that sets the host name to @var{name}.
17600 @defvr {Scheme Variable} console-font-service-type
17601 Install the given fonts on the specified ttys (fonts are per
17602 virtual console on the kernel Linux). The value of this service is a list of
17603 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
17604 package or any valid argument to @command{setfont}, as in this example:
17607 `(("tty1" . "LatGrkCyr-8x16")
17608 ("tty2" . ,(file-append
17610 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
17611 ("tty3" . ,(file-append
17613 "/share/consolefonts/ter-132n"))) ; for HDPI
17617 @deffn {Scheme Procedure} login-service @var{config}
17618 Return a service to run login according to @var{config}, a
17619 @code{<login-configuration>} object, which specifies the message of the day,
17620 among other things.
17623 @deftp {Data Type} login-configuration
17624 This is the data type representing the configuration of login.
17629 @cindex message of the day
17630 A file-like object containing the ``message of the day''.
17632 @item @code{allow-empty-passwords?} (default: @code{#t})
17633 Allow empty passwords by default so that first-time users can log in when
17634 the 'root' account has just been created.
17639 @deffn {Scheme Procedure} mingetty-service @var{config}
17640 Return a service to run mingetty according to @var{config}, a
17641 @code{<mingetty-configuration>} object, which specifies the tty to run, among
17645 @deftp {Data Type} mingetty-configuration
17646 This is the data type representing the configuration of Mingetty, which
17647 provides the default implementation of virtual console log-in.
17652 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
17654 @item @code{auto-login} (default: @code{#f})
17655 When true, this field must be a string denoting the user name under
17656 which the system automatically logs in. When it is @code{#f}, a
17657 user name and password must be entered to log in.
17659 @item @code{login-program} (default: @code{#f})
17660 This must be either @code{#f}, in which case the default log-in program
17661 is used (@command{login} from the Shadow tool suite), or a gexp denoting
17662 the name of the log-in program.
17664 @item @code{login-pause?} (default: @code{#f})
17665 When set to @code{#t} in conjunction with @var{auto-login}, the user
17666 will have to press a key before the log-in shell is launched.
17668 @item @code{clear-on-logout?} (default: @code{#t})
17669 When set to @code{#t}, the screen will be cleared after logout.
17671 @item @code{mingetty} (default: @var{mingetty})
17672 The Mingetty package to use.
17677 @deffn {Scheme Procedure} agetty-service @var{config}
17678 Return a service to run agetty according to @var{config}, an
17679 @code{<agetty-configuration>} object, which specifies the tty to run,
17680 among other things.
17683 @deftp {Data Type} agetty-configuration
17684 This is the data type representing the configuration of agetty, which
17685 implements virtual and serial console log-in. See the @code{agetty(8)}
17686 man page for more information.
17691 The name of the console this agetty runs on, as a string---e.g.,
17692 @code{"ttyS0"}. This argument is optional, it will default to
17693 a reasonable default serial port used by the kernel Linux.
17695 For this, if there is a value for an option @code{agetty.tty} in the kernel
17696 command line, agetty will extract the device name of the serial port
17697 from it and use that.
17699 If not and if there is a value for an option @code{console} with a tty in
17700 the Linux command line, agetty will extract the device name of the
17701 serial port from it and use that.
17703 In both cases, agetty will leave the other serial device settings
17704 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
17707 @item @code{baud-rate} (default: @code{#f})
17708 A string containing a comma-separated list of one or more baud rates, in
17711 @item @code{term} (default: @code{#f})
17712 A string containing the value used for the @env{TERM} environment
17715 @item @code{eight-bits?} (default: @code{#f})
17716 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
17719 @item @code{auto-login} (default: @code{#f})
17720 When passed a login name, as a string, the specified user will be logged
17721 in automatically without prompting for their login name or password.
17723 @item @code{no-reset?} (default: @code{#f})
17724 When @code{#t}, don't reset terminal cflags (control modes).
17726 @item @code{host} (default: @code{#f})
17727 This accepts a string containing the ``login_host'', which will be written
17728 into the @file{/var/run/utmpx} file.
17730 @item @code{remote?} (default: @code{#f})
17731 When set to @code{#t} in conjunction with @var{host}, this will add an
17732 @code{-r} fakehost option to the command line of the login program
17733 specified in @var{login-program}.
17735 @item @code{flow-control?} (default: @code{#f})
17736 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
17738 @item @code{no-issue?} (default: @code{#f})
17739 When set to @code{#t}, the contents of the @file{/etc/issue} file will
17740 not be displayed before presenting the login prompt.
17742 @item @code{init-string} (default: @code{#f})
17743 This accepts a string that will be sent to the tty or modem before
17744 sending anything else. It can be used to initialize a modem.
17746 @item @code{no-clear?} (default: @code{#f})
17747 When set to @code{#t}, agetty will not clear the screen before showing
17750 @item @code{login-program} (default: (file-append shadow "/bin/login"))
17751 This must be either a gexp denoting the name of a log-in program, or
17752 unset, in which case the default value is the @command{login} from the
17755 @item @code{local-line} (default: @code{#f})
17756 Control the CLOCAL line flag. This accepts one of three symbols as
17757 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
17758 the default value chosen by agetty is @code{'auto}.
17760 @item @code{extract-baud?} (default: @code{#f})
17761 When set to @code{#t}, instruct agetty to try to extract the baud rate
17762 from the status messages produced by certain types of modems.
17764 @item @code{skip-login?} (default: @code{#f})
17765 When set to @code{#t}, do not prompt the user for a login name. This
17766 can be used with @var{login-program} field to use non-standard login
17769 @item @code{no-newline?} (default: @code{#f})
17770 When set to @code{#t}, do not print a newline before printing the
17771 @file{/etc/issue} file.
17773 @c Is this dangerous only when used with login-program, or always?
17774 @item @code{login-options} (default: @code{#f})
17775 This option accepts a string containing options that are passed to the
17776 login program. When used with the @var{login-program}, be aware that a
17777 malicious user could try to enter a login name containing embedded
17778 options that could be parsed by the login program.
17780 @item @code{login-pause} (default: @code{#f})
17781 When set to @code{#t}, wait for any key before showing the login prompt.
17782 This can be used in conjunction with @var{auto-login} to save memory by
17783 lazily spawning shells.
17785 @item @code{chroot} (default: @code{#f})
17786 Change root to the specified directory. This option accepts a directory
17789 @item @code{hangup?} (default: @code{#f})
17790 Use the Linux system call @code{vhangup} to do a virtual hangup of the
17791 specified terminal.
17793 @item @code{keep-baud?} (default: @code{#f})
17794 When set to @code{#t}, try to keep the existing baud rate. The baud
17795 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
17798 @item @code{timeout} (default: @code{#f})
17799 When set to an integer value, terminate if no user name could be read
17800 within @var{timeout} seconds.
17802 @item @code{detect-case?} (default: @code{#f})
17803 When set to @code{#t}, turn on support for detecting an uppercase-only
17804 terminal. This setting will detect a login name containing only
17805 uppercase letters as indicating an uppercase-only terminal and turn on
17806 some upper-to-lower case conversions. Note that this will not support
17807 Unicode characters.
17809 @item @code{wait-cr?} (default: @code{#f})
17810 When set to @code{#t}, wait for the user or modem to send a
17811 carriage-return or linefeed character before displaying
17812 @file{/etc/issue} or login prompt. This is typically used with the
17813 @var{init-string} option.
17815 @item @code{no-hints?} (default: @code{#f})
17816 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
17819 @item @code{no-hostname?} (default: @code{#f})
17820 By default, the hostname is printed. When this option is set to
17821 @code{#t}, no hostname will be shown at all.
17823 @item @code{long-hostname?} (default: @code{#f})
17824 By default, the hostname is only printed until the first dot. When this
17825 option is set to @code{#t}, the fully qualified hostname by
17826 @code{gethostname} or @code{getaddrinfo} is shown.
17828 @item @code{erase-characters} (default: @code{#f})
17829 This option accepts a string of additional characters that should be
17830 interpreted as backspace when the user types their login name.
17832 @item @code{kill-characters} (default: @code{#f})
17833 This option accepts a string that should be interpreted to mean ``ignore
17834 all previous characters'' (also called a ``kill'' character) when the user
17835 types their login name.
17837 @item @code{chdir} (default: @code{#f})
17838 This option accepts, as a string, a directory path that will be changed
17841 @item @code{delay} (default: @code{#f})
17842 This options accepts, as an integer, the number of seconds to sleep
17843 before opening the tty and displaying the login prompt.
17845 @item @code{nice} (default: @code{#f})
17846 This option accepts, as an integer, the nice value with which to run the
17847 @command{login} program.
17849 @item @code{extra-options} (default: @code{'()})
17850 This option provides an ``escape hatch'' for the user to provide arbitrary
17851 command-line arguments to @command{agetty} as a list of strings.
17853 @item @code{shepherd-requirement} (default: @code{'()})
17854 The option can be used to provides extra shepherd requirements (for example
17855 @code{'syslogd}) to the respective @code{'term-}* shepherd service.
17860 @deffn {Scheme Procedure} kmscon-service-type @var{config}
17861 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
17862 according to @var{config}, a @code{<kmscon-configuration>} object, which
17863 specifies the tty to run, among other things.
17866 @deftp {Data Type} kmscon-configuration
17867 This is the data type representing the configuration of Kmscon, which
17868 implements virtual console log-in.
17872 @item @code{virtual-terminal}
17873 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
17875 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
17876 A gexp denoting the name of the log-in program. The default log-in program is
17877 @command{login} from the Shadow tool suite.
17879 @item @code{login-arguments} (default: @code{'("-p")})
17880 A list of arguments to pass to @command{login}.
17882 @item @code{auto-login} (default: @code{#f})
17883 When passed a login name, as a string, the specified user will be logged
17884 in automatically without prompting for their login name or password.
17886 @item @code{hardware-acceleration?} (default: #f)
17887 Whether to use hardware acceleration.
17889 @item @code{font-engine} (default: @code{"pango"})
17890 Font engine used in Kmscon.
17892 @item @code{font-size} (default: @code{12})
17893 Font size used in Kmscon.
17895 @item @code{keyboard-layout} (default: @code{#f})
17896 If this is @code{#f}, Kmscon uses the default keyboard layout---usually US
17897 English (``qwerty'') for a 105-key PC keyboard.
17899 Otherwise this must be a @code{keyboard-layout} object specifying the
17900 keyboard layout. @xref{Keyboard Layout}, for more information on how to
17901 specify the keyboard layout.
17903 @item @code{kmscon} (default: @var{kmscon})
17904 The Kmscon package to use.
17909 @cindex name service cache daemon
17911 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
17912 [#:name-services '()]
17913 Return a service that runs the libc name service cache daemon (nscd) with the
17914 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
17915 Service Switch}, for an example.
17917 For convenience, the Shepherd service for nscd provides the following actions:
17921 @cindex cache invalidation, nscd
17922 @cindex nscd, cache invalidation
17923 This invalidate the given cache. For instance, running:
17926 herd invalidate nscd hosts
17930 invalidates the host name lookup cache of nscd.
17933 Running @command{herd statistics nscd} displays information about nscd usage
17939 @defvr {Scheme Variable} %nscd-default-configuration
17940 This is the default @code{<nscd-configuration>} value (see below) used
17941 by @code{nscd-service}. It uses the caches defined by
17942 @code{%nscd-default-caches}; see below.
17945 @deftp {Data Type} nscd-configuration
17946 This is the data type representing the name service cache daemon (nscd)
17951 @item @code{name-services} (default: @code{'()})
17952 List of packages denoting @dfn{name services} that must be visible to
17953 the nscd---e.g., @code{(list @var{nss-mdns})}.
17955 @item @code{glibc} (default: @var{glibc})
17956 Package object denoting the GNU C Library providing the @command{nscd}
17959 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
17960 Name of the nscd log file. This is where debugging output goes when
17961 @code{debug-level} is strictly positive.
17963 @item @code{debug-level} (default: @code{0})
17964 Integer denoting the debugging levels. Higher numbers mean that more
17965 debugging output is logged.
17967 @item @code{caches} (default: @code{%nscd-default-caches})
17968 List of @code{<nscd-cache>} objects denoting things to be cached; see
17974 @deftp {Data Type} nscd-cache
17975 Data type representing a cache database of nscd and its parameters.
17979 @item @code{database}
17980 This is a symbol representing the name of the database to be cached.
17981 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
17982 @code{services}, which designate the corresponding NSS database
17983 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
17985 @item @code{positive-time-to-live}
17986 @itemx @code{negative-time-to-live} (default: @code{20})
17987 A number representing the number of seconds during which a positive or
17988 negative lookup result remains in cache.
17990 @item @code{check-files?} (default: @code{#t})
17991 Whether to check for updates of the files corresponding to
17994 For instance, when @var{database} is @code{hosts}, setting this flag
17995 instructs nscd to check for updates in @file{/etc/hosts} and to take
17998 @item @code{persistent?} (default: @code{#t})
17999 Whether the cache should be stored persistently on disk.
18001 @item @code{shared?} (default: @code{#t})
18002 Whether the cache should be shared among users.
18004 @item @code{max-database-size} (default: 32@tie{}MiB)
18005 Maximum size in bytes of the database cache.
18007 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
18008 @c settings, so leave them out.
18013 @defvr {Scheme Variable} %nscd-default-caches
18014 List of @code{<nscd-cache>} objects used by default by
18015 @code{nscd-configuration} (see above).
18017 It enables persistent and aggressive caching of service and host name
18018 lookups. The latter provides better host name lookup performance,
18019 resilience in the face of unreliable name servers, and also better
18020 privacy---often the result of host name lookups is in local cache, so
18021 external name servers do not even need to be queried.
18024 @anchor{syslog-configuration-type}
18027 @deftp {Data Type} syslog-configuration
18028 This data type represents the configuration of the syslog daemon.
18031 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
18032 The syslog daemon to use.
18034 @item @code{config-file} (default: @code{%default-syslog.conf})
18035 The syslog configuration file to use.
18040 @anchor{syslog-service}
18042 @deffn {Scheme Procedure} syslog-service @var{config}
18043 Return a service that runs a syslog daemon according to @var{config}.
18045 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
18046 information on the configuration file syntax.
18049 @defvr {Scheme Variable} guix-service-type
18050 This is the type of the service that runs the build daemon,
18051 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
18052 @code{guix-configuration} record as described below.
18055 @anchor{guix-configuration-type}
18056 @deftp {Data Type} guix-configuration
18057 This data type represents the configuration of the Guix build daemon.
18058 @xref{Invoking guix-daemon}, for more information.
18061 @item @code{guix} (default: @var{guix})
18062 The Guix package to use.
18064 @item @code{build-group} (default: @code{"guixbuild"})
18065 Name of the group for build user accounts.
18067 @item @code{build-accounts} (default: @code{10})
18068 Number of build user accounts to create.
18070 @item @code{authorize-key?} (default: @code{#t})
18071 @cindex substitutes, authorization thereof
18072 Whether to authorize the substitute keys listed in
18073 @code{authorized-keys}---by default that of
18074 @code{@value{SUBSTITUTE-SERVER-1}} and
18075 @code{@value{SUBSTITUTE-SERVER-2}}
18076 (@pxref{Substitutes}).
18078 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
18079 changed by invoking @command{guix archive --authorize}. You must
18080 instead adjust @code{guix-configuration} as you wish and reconfigure the
18081 system. This ensures that your operating system configuration file is
18085 When booting or reconfiguring to a system where @code{authorize-key?}
18086 is true, the existing @file{/etc/guix/acl} file is backed up as
18087 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
18088 file. This is to facilitate migration from earlier versions, which
18089 allowed for in-place modifications to @file{/etc/guix/acl}.
18092 @vindex %default-authorized-guix-keys
18093 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
18094 The list of authorized key files for archive imports, as a list of
18095 string-valued gexps (@pxref{Invoking guix archive}). By default, it
18096 contains that of @code{@value{SUBSTITUTE-SERVER-1}} and
18097 @code{@value{SUBSTITUTE-SERVER-2}} (@pxref{Substitutes}). See
18098 @code{substitute-urls} below for an example on how to change it.
18100 @item @code{use-substitutes?} (default: @code{#t})
18101 Whether to use substitutes.
18103 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
18104 The list of URLs where to look for substitutes by default.
18106 Suppose you would like to fetch substitutes from @code{guix.example.org}
18107 in addition to @code{@value{SUBSTITUTE-SERVER-1}}. You will need to do
18108 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
18109 and (2) authorize its signing key, having done appropriate checks
18110 (@pxref{Substitute Server Authorization}). The configuration below does
18114 (guix-configuration
18116 (append (list "https://guix.example.org")
18117 %default-substitute-urls))
18119 (append (list (local-file "./guix.example.org-key.pub"))
18120 %default-authorized-guix-keys)))
18123 This example assumes that the file @file{./guix.example.org-key.pub}
18124 contains the public key that @code{guix.example.org} uses to sign
18127 @item @code{generate-substitute-key?} (default: @code{#t})
18128 Whether to generate a @dfn{substitute key pair} under
18129 @file{/etc/guix/signing-key.pub} and @file{/etc/guix/signing-key.sec} if
18130 there is not already one.
18132 This key pair is used when exporting store items, for instance with
18133 @command{guix publish} (@pxref{Invoking guix publish}) or @command{guix
18134 archive} (@pxref{Invoking guix archive}). Generating a key pair takes a
18135 few seconds when enough entropy is available and is only done once; you
18136 might want to turn it off for instance in a virtual machine that does
18137 not need it and where the extra boot time is a problem.
18139 @item @code{max-silent-time} (default: @code{0})
18140 @itemx @code{timeout} (default: @code{0})
18141 The number of seconds of silence and the number of seconds of activity,
18142 respectively, after which a build process times out. A value of zero
18143 disables the timeout.
18145 @item @code{log-compression} (default: @code{'gzip})
18146 The type of compression used for build logs---one of @code{gzip},
18147 @code{bzip2}, or @code{none}.
18149 @item @code{discover?} (default: @code{#f})
18150 Whether to discover substitute servers on the local network using mDNS
18153 @item @code{extra-options} (default: @code{'()})
18154 List of extra command-line options for @command{guix-daemon}.
18156 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
18157 File where @command{guix-daemon}'s standard output and standard error
18160 @cindex HTTP proxy, for @code{guix-daemon}
18161 @cindex proxy, for @code{guix-daemon} HTTP access
18162 @item @code{http-proxy} (default: @code{#f})
18163 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
18164 derivations and substitutes.
18166 It is also possible to change the daemon's proxy at run time through the
18167 @code{set-http-proxy} action, which restarts it:
18170 herd set-http-proxy guix-daemon http://localhost:8118
18173 To clear the proxy settings, run:
18176 herd set-http-proxy guix-daemon
18179 @item @code{tmpdir} (default: @code{#f})
18180 A directory path where the @command{guix-daemon} will perform builds.
18185 @deftp {Data Type} guix-extension
18187 This data type represents the parameters of the Guix build daemon that
18188 are extendable. This is the type of the object that must be used within
18189 a guix service extension.
18190 @xref{Service Composition}, for more information.
18193 @item @code{authorized-keys} (default: @code{'()})
18194 A list of file-like objects where each element contains a public key.
18196 @item @code{substitute-urls} (default: @code{'()})
18197 A list of strings where each element is a substitute URL.
18199 @item @code{chroot-directories} (default: @code{'()})
18200 A list of file-like objects or strings pointing to additional directories the build daemon can use.
18204 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
18205 Run @var{udev}, which populates the @file{/dev} directory dynamically.
18206 udev rules can be provided as a list of files through the @var{rules}
18207 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
18208 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
18209 creation of such rule files.
18211 The @command{herd rules udev} command, as root, returns the name of the
18212 directory containing all the active udev rules.
18215 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
18216 Return a udev-rule file named @var{file-name} containing the rules
18217 defined by the @var{contents} literal.
18219 In the following example, a rule for a USB device is defined to be
18220 stored in the file @file{90-usb-thing.rules}. The rule runs a script
18221 upon detecting a USB device with a given product identifier.
18224 (define %example-udev-rule
18226 "90-usb-thing.rules"
18227 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
18228 "ATTR@{product@}==\"Example\", "
18229 "RUN+=\"/path/to/script\"")))
18233 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
18234 [#:groups @var{groups}]
18235 Return a service that extends @code{udev-service-type } with @var{rules}
18236 and @code{account-service-type} with @var{groups} as system groups.
18237 This works by creating a singleton service type
18238 @code{@var{name}-udev-rules}, of which the returned service is an
18241 Here we show how it can be used to extend @code{udev-service-type} with the
18242 previously defined rule @code{%example-udev-rule}.
18248 (cons (udev-rules-service 'usb-thing %example-udev-rule)
18249 %desktop-services)))
18253 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
18254 Return a udev file named @var{file-name} containing the rules defined
18255 within @var{file}, a file-like object.
18257 The following example showcases how we can use an existing rule file.
18260 (use-modules (guix download) ;for url-fetch
18261 (guix packages) ;for origin
18264 (define %android-udev-rules
18266 "51-android-udev.rules"
18267 (let ((version "20170910"))
18270 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
18271 "android-udev-rules/" version "/51-android.rules"))
18273 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
18277 Additionally, Guix package definitions can be included in @var{rules} in
18278 order to extend the udev rules with the definitions found under their
18279 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
18280 @var{file->udev-rule} example, we could have used the
18281 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
18282 packages android)} module.
18284 The following example shows how to use the @var{android-udev-rules}
18285 package so that the Android tool @command{adb} can detect devices
18286 without root privileges. It also details how to create the
18287 @code{adbusers} group, which is required for the proper functioning of
18288 the rules defined within the @code{android-udev-rules} package. To
18289 create such a group, we must define it both as part of the
18290 @code{supplementary-groups} of our @code{user-account} declaration, as
18291 well as in the @var{groups} of the @code{udev-rules-service} procedure.
18294 (use-modules (gnu packages android) ;for android-udev-rules
18295 (gnu system shadow) ;for user-group
18300 (users (cons (user-account
18302 (supplementary-groups
18303 '("adbusers" ;for adb
18304 "wheel" "netdev" "audio" "video")))))
18307 (cons (udev-rules-service 'android android-udev-rules
18308 #:groups '("adbusers"))
18309 %desktop-services)))
18312 @defvr {Scheme Variable} urandom-seed-service-type
18313 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
18314 when rebooting. It also tries to seed @file{/dev/urandom} from
18315 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
18319 @defvr {Scheme Variable} %random-seed-file
18320 This is the name of the file where some random bytes are saved by
18321 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
18322 It defaults to @file{/var/lib/random-seed}.
18327 @defvr {Scheme Variable} gpm-service-type
18328 This is the type of the service that runs GPM, the @dfn{general-purpose
18329 mouse daemon}, which provides mouse support to the Linux console. GPM
18330 allows users to use the mouse in the console, notably to select, copy,
18333 The value for services of this type must be a @code{gpm-configuration}
18334 (see below). This service is not part of @code{%base-services}.
18337 @deftp {Data Type} gpm-configuration
18338 Data type representing the configuration of GPM.
18341 @item @code{options} (default: @code{%default-gpm-options})
18342 Command-line options passed to @command{gpm}. The default set of
18343 options instruct @command{gpm} to listen to mouse events on
18344 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
18347 @item @code{gpm} (default: @code{gpm})
18348 The GPM package to use.
18353 @anchor{guix-publish-service-type}
18354 @deffn {Scheme Variable} guix-publish-service-type
18355 This is the service type for @command{guix publish} (@pxref{Invoking
18356 guix publish}). Its value must be a @code{guix-publish-configuration}
18357 object, as described below.
18359 This assumes that @file{/etc/guix} already contains a signing key pair as
18360 created by @command{guix archive --generate-key} (@pxref{Invoking guix
18361 archive}). If that is not the case, the service will fail to start.
18364 @deftp {Data Type} guix-publish-configuration
18365 Data type representing the configuration of the @code{guix publish}
18369 @item @code{guix} (default: @code{guix})
18370 The Guix package to use.
18372 @item @code{port} (default: @code{80})
18373 The TCP port to listen for connections.
18375 @item @code{host} (default: @code{"localhost"})
18376 The host (and thus, network interface) to listen to. Use
18377 @code{"0.0.0.0"} to listen on all the network interfaces.
18379 @item @code{advertise?} (default: @code{#f})
18380 When true, advertise the service on the local network @i{via} the DNS-SD
18381 protocol, using Avahi.
18383 This allows neighboring Guix devices with discovery on (see
18384 @code{guix-configuration} above) to discover this @command{guix publish}
18385 instance and to automatically download substitutes from it.
18387 @item @code{compression} (default: @code{'(("gzip" 3) ("zstd" 3))})
18388 This is a list of compression method/level tuple used when compressing
18389 substitutes. For example, to compress all substitutes with @emph{both} lzip
18390 at level 7 and gzip at level 9, write:
18393 '(("lzip" 7) ("gzip" 9))
18396 Level 9 achieves the best compression ratio at the expense of increased CPU
18397 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
18398 publish}, for more information on the available compression methods and
18399 the tradeoffs involved.
18401 An empty list disables compression altogether.
18403 @item @code{nar-path} (default: @code{"nar"})
18404 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
18405 publish, @option{--nar-path}}, for details.
18407 @item @code{cache} (default: @code{#f})
18408 When it is @code{#f}, disable caching and instead generate archives on
18409 demand. Otherwise, this should be the name of a directory---e.g.,
18410 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
18411 archives and meta-data ready to be sent. @xref{Invoking guix publish,
18412 @option{--cache}}, for more information on the tradeoffs involved.
18414 @item @code{workers} (default: @code{#f})
18415 When it is an integer, this is the number of worker threads used for
18416 caching; when @code{#f}, the number of processors is used.
18417 @xref{Invoking guix publish, @option{--workers}}, for more information.
18419 @item @code{cache-bypass-threshold} (default: 10 MiB)
18420 When @code{cache} is true, this is the maximum size in bytes of a store
18421 item for which @command{guix publish} may bypass its cache in case of a
18422 cache miss. @xref{Invoking guix publish,
18423 @option{--cache-bypass-threshold}}, for more information.
18425 @item @code{ttl} (default: @code{#f})
18426 When it is an integer, this denotes the @dfn{time-to-live} in seconds
18427 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
18428 for more information.
18430 @item @code{negative-ttl} (default: @code{#f})
18431 When it is an integer, this denotes the @dfn{time-to-live} in
18432 seconds for the negative lookups. @xref{Invoking guix publish,
18433 @option{--negative-ttl}}, for more information.
18437 @anchor{rngd-service}
18438 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
18439 [#:device "/dev/hwrng"]
18440 Return a service that runs the @command{rngd} program from @var{rng-tools}
18441 to add @var{device} to the kernel's entropy pool. The service will fail if
18442 @var{device} does not exist.
18445 @anchor{pam-limits-service}
18446 @cindex session limits
18452 @cindex open file descriptors
18453 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
18455 Return a service that installs a configuration file for the
18456 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
18457 @code{pam_limits} module}. The procedure optionally takes a list of
18458 @code{pam-limits-entry} values, which can be used to specify
18459 @code{ulimit} limits and @code{nice} priority limits to user sessions.
18461 The following limits definition sets two hard and soft limits for all
18462 login sessions of users in the @code{realtime} group:
18465 (pam-limits-service
18467 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
18468 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
18471 The first entry increases the maximum realtime priority for
18472 non-privileged processes; the second entry lifts any restriction of the
18473 maximum address space that can be locked in memory. These settings are
18474 commonly used for real-time audio systems.
18476 Another useful example is raising the maximum number of open file
18477 descriptors that can be used:
18480 (pam-limits-service
18482 (pam-limits-entry "*" 'both 'nofile 100000)))
18485 In the above example, the asterisk means the limit should apply to any
18486 user. It is important to ensure the chosen value doesn't exceed the
18487 maximum system value visible in the @file{/proc/sys/fs/file-max} file,
18488 else the users would be prevented from login in. For more information
18489 about the Pluggable Authentication Module (PAM) limits, refer to the
18490 @samp{pam_limits} man page from the @code{linux-pam} package.
18493 @defvr {Scheme Variable} greetd-service-type
18494 @uref{https://git.sr.ht/~kennylevinsen/greetd, @code{greetd}} is a minimal and
18495 flexible login manager daemon, that makes no assumptions about what you
18498 If you can run it from your shell in a TTY, greetd can start it. If it
18499 can be taught to speak a simple JSON-based IPC protocol, then it can be
18502 @code{greetd-service-type} provides necessary infrastructure for logging
18503 in users, including:
18507 @code{greetd} PAM service
18510 Special variation of @code{pam-mount} to mount @code{XDG_RUNTIME_DIR}
18513 Here is example of switching from @code{mingetty-service-type} to
18514 @code{greetd-service-type}, and how different terminals could be:
18518 (modify-services %base-services
18519 ;; greetd-service-type provides "greetd" PAM service
18520 (delete login-service-type)
18521 ;; and can be used in place of mingetty-service-type
18522 (delete mingetty-service-type))
18524 (service greetd-service-type
18525 (greetd-configuration
18528 ;; we can make any terminal active by default
18529 (greetd-terminal-configuration (terminal-vt "1") (terminal-switch #t))
18530 ;; we can make environment without XDG_RUNTIME_DIR set
18531 ;; even provide our own environment variables
18532 (greetd-terminal-configuration
18534 (default-session-command
18535 (greetd-agreety-session
18536 (extra-env '(("MY_VAR" . "1")))
18538 ;; we can use different shell instead of default bash
18539 (greetd-terminal-configuration
18541 (default-session-command
18542 (greetd-agreety-session (command (file-append zsh "/bin/zsh")))))
18543 ;; we can use any other executable command as greeter
18544 (greetd-terminal-configuration
18546 (default-session-command (program-file "my-noop-greeter" #~(exit))))
18547 (greetd-terminal-configuration (terminal-vt "5"))
18548 (greetd-terminal-configuration (terminal-vt "6"))))))
18549 ;; mingetty-service-type can be used in parallel
18550 ;; if needed to do so, do not (delete login-service-type)
18551 ;; as illustrated above
18552 #| (service mingetty-service-type (mingetty-configuration (tty "tty8"))) |#))
18556 @deftp {Data Type} greetd-configuration
18557 Configuration record for the @code{greetd-service-type}.
18561 A file-like object containing the ``message of the day''.
18563 @item @code{allow-empty-passwords?} (default: @code{#t})
18564 Allow empty passwords by default so that first-time users can log in when
18565 the 'root' account has just been created.
18567 @item @code{terminals} (default: @code{'()})
18568 List of @code{greetd-terminal-configuration} per terminal for which
18569 @code{greetd} should be started.
18571 @item @code{greeter-supplementary-groups} (default: @code{'()})
18572 List of groups which should be added to @code{greeter} user. For instance:
18574 (greeter-supplementary-groups '("seat" "video"))
18576 Note that this example will fail if @code{seat} group does not exist.
18580 @deftp {Data Type} greetd-terminal-configuration
18581 Configuration record for per terminal greetd daemon service.
18584 @item @code{greetd} (default: @code{greetd})
18585 The greetd package to use.
18587 @item @code{config-file-name}
18588 Configuration file name to use for greetd daemon. Generally, autogenerated
18589 derivation based on @code{terminal-vt} value.
18591 @item @code{log-file-name}
18592 Log file name to use for greetd daemon. Generally, autogenerated
18593 name based on @code{terminal-vt} value.
18595 @item @code{terminal-vt} (default: @samp{"7"})
18596 The VT to run on. Use of a specific VT with appropriate conflict avoidance
18599 @item @code{terminal-switch} (default: @code{#f})
18600 Make this terminal active on start of @code{greetd}.
18602 @item @code{default-session-user} (default: @samp{"greeter"})
18603 The user to use for running the greeter.
18605 @item @code{default-session-command} (default: @code{(greetd-agreety-session)})
18606 Can be either instance of @code{greetd-agreety-session} configuration or
18607 @code{gexp->script} like object to use as greeter.
18612 @deftp {Data Type} greetd-agreety-session
18613 Configuration record for the agreety greetd greeter.
18616 @item @code{agreety} (default: @code{greetd})
18617 The package with @command{/bin/agreety} command.
18619 @item @code{command} (default: @code{(file-append bash "/bin/bash")})
18620 Command to be started by @command{/bin/agreety} on successful login.
18622 @item @code{command-args} (default: @code{'("-l")})
18623 Command arguments to pass to command.
18625 @item @code{extra-env} (default: @code{'()})
18626 Extra environment variables to set on login.
18628 @item @code{xdg-env?} (default: @code{#t})
18629 If true @code{XDG_RUNTIME_DIR} and @code{XDG_SESSION_TYPE} will be set
18630 before starting command. One should note that, @code{extra-env} variables
18631 are set right after mentioned variables, so that they can be overriden.
18636 @node Scheduled Job Execution
18637 @subsection Scheduled Job Execution
18641 @cindex scheduling jobs
18642 The @code{(gnu services mcron)} module provides an interface to
18643 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
18644 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
18645 Unix @command{cron} daemon; the main difference is that it is
18646 implemented in Guile Scheme, which provides a lot of flexibility when
18647 specifying the scheduling of jobs and their actions.
18649 The example below defines an operating system that runs the
18650 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
18651 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
18652 well as the @command{mkid} command on behalf of an unprivileged user
18653 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
18654 gexps to introduce job definitions that are passed to mcron
18655 (@pxref{G-Expressions}).
18658 (use-modules (guix) (gnu) (gnu services mcron))
18659 (use-package-modules base idutils)
18661 (define updatedb-job
18662 ;; Run 'updatedb' at 3AM every day. Here we write the
18663 ;; job's action as a Scheme procedure.
18664 #~(job '(next-hour '(3))
18666 (execl (string-append #$findutils "/bin/updatedb")
18668 "--prunepaths=/tmp /var/tmp /gnu/store"))
18671 (define garbage-collector-job
18672 ;; Collect garbage 5 minutes after midnight every day.
18673 ;; The job's action is a shell command.
18674 #~(job "5 0 * * *" ;Vixie cron syntax
18677 (define idutils-job
18678 ;; Update the index database as user "charlie" at 12:15PM
18679 ;; and 19:15PM. This runs from the user's home directory.
18680 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
18681 (string-append #$idutils "/bin/mkid src")
18687 ;; %BASE-SERVICES already includes an instance of
18688 ;; 'mcron-service-type', which we extend with additional
18689 ;; jobs using 'simple-service'.
18690 (services (cons (simple-service 'my-cron-jobs
18692 (list garbage-collector-job
18699 When providing the action of a job specification as a procedure, you
18700 should provide an explicit name for the job via the optional 3rd
18701 argument as done in the @code{updatedb-job} example above. Otherwise,
18702 the job would appear as ``Lambda function'' in the output of
18703 @command{herd schedule mcron}, which is not nearly descriptive enough!
18706 For more complex jobs defined in Scheme where you need control over the top
18707 level, for instance to introduce a @code{use-modules} form, you can move your
18708 code to a separate program using the @code{program-file} procedure of the
18709 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
18713 (define %battery-alert-job
18714 ;; Beep when the battery percentage falls below %MIN-LEVEL.
18716 '(next-minute (range 0 60 1))
18718 "battery-alert.scm"
18719 (with-imported-modules (source-module-closure
18720 '((guix build utils)))
18722 (use-modules (guix build utils)
18725 (ice-9 textual-ports)
18728 (define %min-level 20)
18730 (setenv "LC_ALL" "C") ;ensure English output
18731 (and-let* ((input-pipe (open-pipe*
18733 #$(file-append acpi "/bin/acpi")))
18734 (output (get-string-all input-pipe))
18735 (m (string-match "Discharging, ([0-9]+)%" output))
18736 (level (string->number (match:substring m 1)))
18737 ((< level %min-level)))
18738 (format #t "warning: Battery level is low (~a%)~%" level)
18739 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
18742 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
18743 for more information on mcron job specifications. Below is the
18744 reference of the mcron service.
18746 On a running system, you can use the @code{schedule} action of the service to
18747 visualize the mcron jobs that will be executed next:
18750 # herd schedule mcron
18754 The example above lists the next five tasks that will be executed, but you can
18755 also specify the number of tasks to display:
18758 # herd schedule mcron 10
18761 @defvr {Scheme Variable} mcron-service-type
18762 This is the type of the @code{mcron} service, whose value is an
18763 @code{mcron-configuration} object.
18765 This service type can be the target of a service extension that provides
18766 additional job specifications (@pxref{Service Composition}). In other
18767 words, it is possible to define services that provide additional mcron
18771 @deftp {Data Type} mcron-configuration
18772 Data type representing the configuration of mcron.
18775 @item @code{mcron} (default: @var{mcron})
18776 The mcron package to use.
18779 This is a list of gexps (@pxref{G-Expressions}), where each gexp
18780 corresponds to an mcron job specification (@pxref{Syntax, mcron job
18781 specifications,, mcron, GNU@tie{}mcron}).
18787 @subsection Log Rotation
18790 @cindex log rotation
18792 Log files such as those found in @file{/var/log} tend to grow endlessly,
18793 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
18794 their contents in separate files, possibly compressed. The @code{(gnu
18795 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
18796 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
18798 This service is part of @code{%base-services}, and thus enabled by
18799 default, with the default settings, for commonly encountered log files.
18800 The example below shows how to extend it with an additional
18801 @dfn{rotation}, should you need to do that (usually, services that
18802 produce log files already take care of that):
18805 (use-modules (guix) (gnu))
18806 (use-service-modules admin)
18808 (define my-log-files
18809 ;; Log files that I want to rotate.
18810 '("/var/log/something.log" "/var/log/another.log"))
18814 (services (cons (simple-service 'rotate-my-stuff
18815 rottlog-service-type
18816 (list (log-rotation
18818 (files my-log-files))))
18822 @defvr {Scheme Variable} rottlog-service-type
18823 This is the type of the Rottlog service, whose value is a
18824 @code{rottlog-configuration} object.
18826 Other services can extend this one with new @code{log-rotation} objects
18827 (see below), thereby augmenting the set of files to be rotated.
18829 This service type can define mcron jobs (@pxref{Scheduled Job
18830 Execution}) to run the rottlog service.
18833 @deftp {Data Type} rottlog-configuration
18834 Data type representing the configuration of rottlog.
18837 @item @code{rottlog} (default: @code{rottlog})
18838 The Rottlog package to use.
18840 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
18841 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
18842 rottlog, GNU Rot[t]log Manual}).
18844 @item @code{rotations} (default: @code{%default-rotations})
18845 A list of @code{log-rotation} objects as defined below.
18848 This is a list of gexps where each gexp corresponds to an mcron job
18849 specification (@pxref{Scheduled Job Execution}).
18853 @deftp {Data Type} log-rotation
18854 Data type representing the rotation of a group of log files.
18856 Taking an example from the Rottlog manual (@pxref{Period Related File
18857 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
18863 (files '("/var/log/apache/*"))
18864 (options '("storedir apache-archives"
18870 The list of fields is as follows:
18873 @item @code{frequency} (default: @code{'weekly})
18874 The log rotation frequency, a symbol.
18877 The list of files or file glob patterns to rotate.
18879 @vindex %default-log-rotation-options
18880 @item @code{options} (default: @code{%default-log-rotation-options})
18881 The list of rottlog options for this rotation (@pxref{Configuration
18882 parameters,,, rottlog, GNU Rot[t]log Manual}).
18884 @item @code{post-rotate} (default: @code{#f})
18885 Either @code{#f} or a gexp to execute once the rotation has completed.
18889 @defvr {Scheme Variable} %default-rotations
18890 Specifies weekly rotation of @code{%rotated-files} and of
18891 @file{/var/log/guix-daemon.log}.
18894 @defvr {Scheme Variable} %rotated-files
18895 The list of syslog-controlled files to be rotated. By default it is:
18896 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
18897 "/var/log/maillog")}.
18900 Some log files just need to be deleted periodically once they are old,
18901 without any other criterion and without any archival step. This is the
18902 case of build logs stored by @command{guix-daemon} under
18903 @file{/var/log/guix/drvs} (@pxref{Invoking guix-daemon}). The
18904 @code{log-cleanup} service addresses this use case. For example,
18905 @code{%base-services} (@pxref{Base Services}) includes the following:
18908 ;; Periodically delete old build logs.
18909 (service log-cleanup-service-type
18910 (log-cleanup-configuration
18911 (directory "/var/log/guix/drvs")))
18914 That ensures build logs do not accumulate endlessly.
18916 @defvr {Scheme Variable} log-cleanup-service-type
18917 This is the type of the service to delete old logs. Its value must be a
18918 @code{log-cleanup-configuration} record as described below.
18921 @deftp {Data Type} log-cleanup-configuration
18922 Data type representing the log cleanup configuration
18925 @item @code{directory}
18926 Name of the directory containing log files.
18928 @item @code{expiry} (default: @code{(* 6 30 24 3600)})
18929 Age in seconds after which a file is subject to deletion (six months by
18932 @item @code{schedule} (default: @code{"30 12 01,08,15,22 * *"})
18933 String or gexp denoting the corresponding mcron job schedule
18934 (@pxref{Scheduled Job Execution}).
18938 @cindex logging, anonymization
18939 @subheading Anonip Service
18941 Anonip is a privacy filter that removes IP address from web server logs.
18942 This service creates a FIFO and filters any written lines with anonip
18943 before writing the filtered log to a target file.
18945 The following example sets up the FIFO
18946 @file{/var/run/anonip/https.access.log} and writes the filtered log file
18947 @file{/var/log/anonip/https.access.log}.
18950 (service anonip-service-type
18951 (anonip-configuration
18952 (input "/var/run/anonip/https.access.log")
18953 (output "/var/log/anonip/https.access.log")))
18956 Configure your web server to write its logs to the FIFO at
18957 @file{/var/run/anonip/https.access.log} and collect the anonymized log
18958 file at @file{/var/web-logs/https.access.log}.
18960 @deftp {Data Type} anonip-configuration
18961 This data type represents the configuration of anonip.
18962 It has the following parameters:
18965 @item @code{anonip} (default: @code{anonip})
18966 The anonip package to use.
18969 The file name of the input log file to process. The service creates a
18970 FIFO of this name. The web server should write its logs to this FIFO.
18972 @item @code{output}
18973 The file name of the processed log file.
18976 The following optional settings may be provided:
18979 @item @code{skip-private?}
18980 When @code{#true} do not mask addresses in private ranges.
18982 @item @code{column}
18983 A 1-based indexed column number. Assume IP address is in the specified
18984 column (default is 1).
18986 @item @code{replacement}
18987 Replacement string in case address parsing fails, e.g. @code{"0.0.0.0"}.
18989 @item @code{ipv4mask}
18990 Number of bits to mask in IPv4 addresses.
18992 @item @code{ipv6mask}
18993 Number of bits to mask in IPv6 addresses.
18995 @item @code{increment}
18996 Increment the IP address by the given number. By default this is zero.
18998 @item @code{delimiter}
18999 Log delimiter string.
19002 Regular expression for detecting IP addresses. Use this instead of @code{column}.
19007 @node Networking Setup
19008 @subsection Networking Setup
19010 The @code{(gnu services networking)} module provides services to
19011 configure network interfaces and set up networking on your machine.
19012 Those services provide different ways for you to set up your machine: by
19013 declaring a static network configuration, by running a Dynamic Host
19014 Configuration Protocol (DHCP) client, or by running daemons such as
19015 NetworkManager and Connman that automate the whole process,
19016 automatically adapt to connectivity changes, and provide a high-level
19019 On a laptop, NetworkManager and Connman are by far the most convenient
19020 options, which is why the default desktop services include
19021 NetworkManager (@pxref{Desktop Services, @code{%desktop-services}}).
19022 For a server, or for a virtual machine or a container, static network
19023 configuration or a simple DHCP client are often more appropriate.
19025 This section describes the various network setup services available,
19026 starting with static network configuration.
19028 @defvr {Scheme Variable} static-networking-service-type
19029 This is the type for statically-configured network interfaces. Its
19030 value must be a list of @code{static-networking} records. Each of them
19031 declares a set of @dfn{addresses}, @dfn{routes}, and @dfn{links}, as
19034 @cindex network interface controller (NIC)
19035 @cindex NIC, networking interface controller
19036 Here is the simplest configuration, with only one network interface
19037 controller (NIC) and only IPv4 connectivity:
19040 ;; Static networking for one NIC, IPv4-only.
19041 (service static-networking-service-type
19042 (list (static-networking
19044 (list (network-address
19046 (value "10.0.2.15/24"))))
19048 (list (network-route
19049 (destination "default")
19050 (gateway "10.0.2.2"))))
19051 (name-servers '("10.0.2.3")))))
19054 The snippet above can be added to the @code{services} field of your
19055 operating system configuration (@pxref{Using the Configuration System}).
19056 It will configure your machine to have 10.0.2.15 as its IP address, with
19057 a 24-bit netmask for the local network---meaning that any 10.0.2.@var{x}
19058 address is on the local area network (LAN). Traffic to addresses
19059 outside the local network is routed @i{via} 10.0.2.2. Host names are
19060 resolved by sending domain name system (DNS) queries to 10.0.2.3.
19063 @deftp {Data Type} static-networking
19064 This is the data type representing a static network configuration.
19066 As an example, here is how you would declare the configuration of a
19067 machine with a single network interface controller (NIC) available as
19068 @code{eno1}, and with one IPv4 and one IPv6 address:
19071 ;; Network configuration for one NIC, IPv4 + IPv6.
19073 (addresses (list (network-address
19075 (value "10.0.2.15/24"))
19078 (value "2001:123:4567:101::1/64"))))
19079 (routes (list (network-route
19080 (destination "default")
19081 (gateway "10.0.2.2"))
19083 (destination "default")
19084 (gateway "2020:321:4567:42::1"))))
19085 (name-servers '("10.0.2.3")))
19088 If you are familiar with the @command{ip} command of the
19089 @uref{https://wiki.linuxfoundation.org/networking/iproute2,
19090 @code{iproute2} package} found on Linux-based systems, the declaration
19091 above is equivalent to typing:
19094 ip address add 10.0.2.15/24 dev eno1
19095 ip address add 2001:123:4567:101::1/64 dev eno1
19096 ip route add default via inet 10.0.2.2
19097 ip route add default via inet6 2020:321:4567:42::1
19100 Run @command{man 8 ip} for more info. Venerable GNU/Linux users will
19101 certainly know how to do it with @command{ifconfig} and @command{route},
19102 but we'll spare you that.
19104 The available fields of this data type are as follows:
19107 @item @code{addresses}
19108 @itemx @code{links} (default: @code{'()})
19109 @itemx @code{routes} (default: @code{'()})
19110 The list of @code{network-address}, @code{network-link}, and
19111 @code{network-route} records for this network (see below).
19113 @item @code{name-servers} (default: @code{'()})
19114 The list of IP addresses (strings) of domain name servers. These IP
19115 addresses go to @file{/etc/resolv.conf}.
19117 @item @code{provision} (default: @code{'(networking)})
19118 If true, this should be a list of symbols for the Shepherd service
19119 corresponding to this network configuration.
19121 @item @code{requirement} (default @code{'()})
19122 The list of Shepherd services depended on.
19126 @deftp {Data Type} network-address
19127 This is the data type representing the IP address of a network
19132 The name of the network interface for this address---e.g.,
19136 The actual IP address and network mask, in
19137 @uref{https://en.wikipedia.org/wiki/CIDR#CIDR_notation, @acronym{CIDR,
19138 Classless Inter-Domain Routing} notation}, as a string.
19140 For example, @code{"10.0.2.15/24"} denotes IPv4 address 10.0.2.15 on a
19141 24-bit sub-network---all 10.0.2.@var{x} addresses are on the same local
19145 Whether @code{value} denotes an IPv6 address. By default this is
19146 automatically determined.
19150 @deftp {Data Type} network-route
19151 This is the data type representing a network route.
19154 @item @code{destination}
19155 The route destination (a string), either an IP address or
19156 @code{"default"} to denote the default route.
19158 @item @code{source} (default: @code{#f})
19161 @item @code{device} (default: @code{#f})
19162 The device used for this route---e.g., @code{"eno2"}.
19164 @item @code{ipv6?} (default: auto)
19165 Whether this is an IPv6 route. By default this is automatically
19166 determined based on @code{destination} or @code{gateway}.
19168 @item @code{gateway} (default: @code{#f})
19169 IP address (a string) through which traffic is routed.
19173 @deftp {Data Type} network-link
19174 Data type for a network link (@pxref{Link,,, guile-netlink,
19175 Guile-Netlink Manual}).
19179 The name of the link---e.g., @code{"v0p0"}.
19182 A symbol denoting the type of the link---e.g., @code{'veth}.
19185 List of arguments for this type of link.
19189 @cindex loopback device
19190 @defvr {Scheme Variable} %loopback-static-networking
19191 This is the @code{static-networking} record representing the ``loopback
19192 device'', @code{lo}, for IP addresses 127.0.0.1 and ::1, and providing
19193 the @code{loopback} Shepherd service.
19196 @cindex networking, with QEMU
19197 @cindex QEMU, networking
19198 @defvr {Scheme Variable} %qemu-static-networking
19199 This is the @code{static-networking} record representing network setup
19200 when using QEMU's user-mode network stack on @code{eth0} (@pxref{Using
19201 the user mode network stack,,, QEMU, QEMU Documentation}).
19204 @cindex DHCP, networking service
19205 @defvr {Scheme Variable} dhcp-client-service-type
19206 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
19207 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
19208 is the DHCP client package to use, @code{isc-dhcp} by default.
19211 @cindex NetworkManager
19213 @defvr {Scheme Variable} network-manager-service-type
19214 This is the service type for the
19215 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
19216 service. The value for this service type is a
19217 @code{network-manager-configuration} record.
19219 This service is part of @code{%desktop-services} (@pxref{Desktop
19223 @deftp {Data Type} network-manager-configuration
19224 Data type representing the configuration of NetworkManager.
19227 @item @code{network-manager} (default: @code{network-manager})
19228 The NetworkManager package to use.
19230 @item @code{dns} (default: @code{"default"})
19231 Processing mode for DNS, which affects how NetworkManager uses the
19232 @code{resolv.conf} configuration file.
19236 NetworkManager will update @code{resolv.conf} to reflect the nameservers
19237 provided by currently active connections.
19240 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
19241 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
19242 then update @code{resolv.conf} to point to the local nameserver.
19244 With this setting, you can share your network connection. For example when
19245 you want to share your network connection to another laptop @i{via} an
19246 Ethernet cable, you can open @command{nm-connection-editor} and configure the
19247 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
19248 and reestablish the connection (or reboot).
19250 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
19251 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
19252 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
19253 browser on your host system, or connect to the VM @i{via} SSH
19254 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
19255 host-to-guest connection, run this command once:
19258 nmcli connection add type tun \
19259 connection.interface-name tap0 \
19260 tun.mode tap tun.owner $(id -u) \
19261 ipv4.method shared \
19262 ipv4.addresses 172.28.112.1/24
19265 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
19266 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
19267 @command{qemu-system-...}.
19270 NetworkManager will not modify @code{resolv.conf}.
19273 @item @code{vpn-plugins} (default: @code{'()})
19274 This is the list of available plugins for virtual private networks
19275 (VPNs). An example of this is the @code{network-manager-openvpn}
19276 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
19282 @deffn {Scheme Variable} connman-service-type
19283 This is the service type to run @url{https://01.org/connman,Connman},
19284 a network connection manager.
19286 Its value must be an
19287 @code{connman-configuration} record as in this example:
19290 (service connman-service-type
19291 (connman-configuration
19292 (disable-vpn? #t)))
19295 See below for details about @code{connman-configuration}.
19298 @deftp {Data Type} connman-configuration
19299 Data Type representing the configuration of connman.
19302 @item @code{connman} (default: @var{connman})
19303 The connman package to use.
19305 @item @code{disable-vpn?} (default: @code{#f})
19306 When true, disable connman's vpn plugin.
19310 @cindex WPA Supplicant
19311 @defvr {Scheme Variable} wpa-supplicant-service-type
19312 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
19313 supplicant}, an authentication daemon required to authenticate against
19314 encrypted WiFi or ethernet networks.
19317 @deftp {Data Type} wpa-supplicant-configuration
19318 Data type representing the configuration of WPA Supplicant.
19320 It takes the following parameters:
19323 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
19324 The WPA Supplicant package to use.
19326 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
19327 List of services that should be started before WPA Supplicant starts.
19329 @item @code{dbus?} (default: @code{#t})
19330 Whether to listen for requests on D-Bus.
19332 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
19333 Where to store the PID file.
19335 @item @code{interface} (default: @code{#f})
19336 If this is set, it must specify the name of a network interface that
19337 WPA supplicant will control.
19339 @item @code{config-file} (default: @code{#f})
19340 Optional configuration file to use.
19342 @item @code{extra-options} (default: @code{'()})
19343 List of additional command-line arguments to pass to the daemon.
19347 @cindex ModemManager
19348 Some networking devices such as modems require special care, and this is
19349 what the services below focus on.
19351 @defvr {Scheme Variable} modem-manager-service-type
19352 This is the service type for the
19353 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
19354 service. The value for this service type is a
19355 @code{modem-manager-configuration} record.
19357 This service is part of @code{%desktop-services} (@pxref{Desktop
19361 @deftp {Data Type} modem-manager-configuration
19362 Data type representing the configuration of ModemManager.
19365 @item @code{modem-manager} (default: @code{modem-manager})
19366 The ModemManager package to use.
19371 @cindex USB_ModeSwitch
19372 @cindex Modeswitching
19374 @defvr {Scheme Variable} usb-modeswitch-service-type
19375 This is the service type for the
19376 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
19377 service. The value for this service type is
19378 a @code{usb-modeswitch-configuration} record.
19380 When plugged in, some USB modems (and other USB devices) initially present
19381 themselves as a read-only storage medium and not as a modem. They need to be
19382 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
19383 installs udev rules to automatically modeswitch these devices when they are
19386 This service is part of @code{%desktop-services} (@pxref{Desktop
19390 @deftp {Data Type} usb-modeswitch-configuration
19391 Data type representing the configuration of USB_ModeSwitch.
19394 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
19395 The USB_ModeSwitch package providing the binaries for modeswitching.
19397 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
19398 The package providing the device data and udev rules file used by
19401 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
19402 Which config file to use for the USB_ModeSwitch dispatcher. By default the
19403 config file shipped with USB_ModeSwitch is used which disables logging to
19404 @file{/var/log} among other default settings. If set to @code{#f}, no config
19411 @node Networking Services
19412 @subsection Networking Services
19414 The @code{(gnu services networking)} module discussed in the previous
19415 section provides services for more advanced setups: providing a DHCP
19416 service for others to use, filtering packets with iptables or nftables,
19417 running a WiFi access point with @command{hostapd}, running the
19418 @command{inetd} ``superdaemon'', and more. This section describes
19421 @deffn {Scheme Procedure} dhcpd-service-type
19422 This type defines a service that runs a DHCP daemon. To create a
19423 service of this type, you must supply a @code{<dhcpd-configuration>}.
19427 (service dhcpd-service-type
19428 (dhcpd-configuration
19429 (config-file (local-file "my-dhcpd.conf"))
19430 (interfaces '("enp0s25"))))
19434 @deftp {Data Type} dhcpd-configuration
19436 @item @code{package} (default: @code{isc-dhcp})
19437 The package that provides the DHCP daemon. This package is expected to
19438 provide the daemon at @file{sbin/dhcpd} relative to its output
19439 directory. The default package is the
19440 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
19441 @item @code{config-file} (default: @code{#f})
19442 The configuration file to use. This is required. It will be passed to
19443 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
19444 object (@pxref{G-Expressions, file-like objects}). See @code{man
19445 dhcpd.conf} for details on the configuration file syntax.
19446 @item @code{version} (default: @code{"4"})
19447 The DHCP version to use. The ISC DHCP server supports the values ``4'',
19448 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
19449 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
19451 @item @code{run-directory} (default: @code{"/run/dhcpd"})
19452 The run directory to use. At service activation time, this directory
19453 will be created if it does not exist.
19454 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
19455 The PID file to use. This corresponds to the @code{-pf} option of
19456 @code{dhcpd}. See @code{man dhcpd} for details.
19457 @item @code{interfaces} (default: @code{'()})
19458 The names of the network interfaces on which dhcpd should listen for
19459 broadcasts. If this list is not empty, then its elements (which must be
19460 strings) will be appended to the @code{dhcpd} invocation when starting
19461 the daemon. It may not be necessary to explicitly specify any
19462 interfaces here; see @code{man dhcpd} for details.
19466 @cindex hostapd service, for Wi-Fi access points
19467 @cindex Wi-Fi access points, hostapd service
19468 @defvr {Scheme Variable} hostapd-service-type
19469 This is the service type to run the @uref{https://w1.fi/hostapd/,
19470 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
19471 authentication servers. Its associated value must be a
19472 @code{hostapd-configuration} as shown below:
19475 ;; Use wlan1 to run the access point for "My Network".
19476 (service hostapd-service-type
19477 (hostapd-configuration
19478 (interface "wlan1")
19479 (ssid "My Network")
19484 @deftp {Data Type} hostapd-configuration
19485 This data type represents the configuration of the hostapd service, with
19486 the following fields:
19489 @item @code{package} (default: @code{hostapd})
19490 The hostapd package to use.
19492 @item @code{interface} (default: @code{"wlan0"})
19493 The network interface to run the WiFi access point.
19496 The SSID (@dfn{service set identifier}), a string that identifies this
19499 @item @code{broadcast-ssid?} (default: @code{#t})
19500 Whether to broadcast this SSID.
19502 @item @code{channel} (default: @code{1})
19503 The WiFi channel to use.
19505 @item @code{driver} (default: @code{"nl80211"})
19506 The driver interface type. @code{"nl80211"} is used with all Linux
19507 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
19508 RADIUS server that does # not control any wireless/wired driver.
19510 @item @code{extra-settings} (default: @code{""})
19511 Extra settings to append as-is to the hostapd configuration file. See
19512 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
19513 configuration file reference.
19517 @defvr {Scheme Variable} simulated-wifi-service-type
19518 This is the type of a service to simulate WiFi networking, which can be
19519 useful in virtual machines for testing purposes. The service loads the
19521 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
19522 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
19523 network that can be seen on @code{wlan0}, by default.
19525 The service's value is a @code{hostapd-configuration} record.
19530 @defvr {Scheme Variable} iptables-service-type
19531 This is the service type to set up an iptables configuration. iptables is a
19532 packet filtering framework supported by the Linux kernel. This service
19533 supports configuring iptables for both IPv4 and IPv6. A simple example
19534 configuration rejecting all incoming connections except those to the ssh port
19538 (service iptables-service-type
19539 (iptables-configuration
19540 (ipv4-rules (plain-file "iptables.rules" "*filter
19544 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19545 -A INPUT -p tcp --dport 22 -j ACCEPT
19546 -A INPUT -j REJECT --reject-with icmp-port-unreachable
19549 (ipv6-rules (plain-file "ip6tables.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 icmp6-port-unreachable
19561 @deftp {Data Type} iptables-configuration
19562 The data type representing the configuration of iptables.
19565 @item @code{iptables} (default: @code{iptables})
19566 The iptables package that provides @code{iptables-restore} and
19567 @code{ip6tables-restore}.
19568 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
19569 The iptables rules to use. It will be passed to @code{iptables-restore}.
19570 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19572 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
19573 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
19574 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19580 @defvr {Scheme Variable} nftables-service-type
19581 This is the service type to set up a nftables configuration. nftables is a
19582 netfilter project that aims to replace the existing iptables, ip6tables,
19583 arptables and ebtables framework. It provides a new packet filtering
19584 framework, a new user-space utility @command{nft}, and a compatibility layer
19585 for iptables. This service comes with a default ruleset
19586 @code{%default-nftables-ruleset} that rejecting all incoming connections
19587 except those to the ssh port 22. To use it, simply write:
19590 (service nftables-service-type)
19594 @deftp {Data Type} nftables-configuration
19595 The data type representing the configuration of nftables.
19598 @item @code{package} (default: @code{nftables})
19599 The nftables package that provides @command{nft}.
19600 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
19601 The nftables ruleset to use. This may be any ``file-like'' object
19602 (@pxref{G-Expressions, file-like objects}).
19606 @cindex NTP (Network Time Protocol), service
19607 @cindex ntpd, service for the Network Time Protocol daemon
19608 @cindex real time clock
19609 @defvr {Scheme Variable} ntp-service-type
19610 This is the type of the service running the @uref{https://www.ntp.org,
19611 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
19612 system clock synchronized with that of the specified NTP servers.
19614 The value of this service is an @code{ntpd-configuration} object, as described
19618 @deftp {Data Type} ntp-configuration
19619 This is the data type for the NTP service configuration.
19622 @item @code{servers} (default: @code{%ntp-servers})
19623 This is the list of servers (@code{<ntp-server>} records) with which
19624 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
19627 @item @code{allow-large-adjustment?} (default: @code{#t})
19628 This determines whether @command{ntpd} is allowed to make an initial
19629 adjustment of more than 1,000 seconds.
19631 @item @code{ntp} (default: @code{ntp})
19632 The NTP package to use.
19636 @defvr {Scheme Variable} %ntp-servers
19637 List of host names used as the default NTP servers. These are servers of the
19638 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
19641 @deftp {Data Type} ntp-server
19642 The data type representing the configuration of a NTP server.
19645 @item @code{type} (default: @code{'server})
19646 The type of the NTP server, given as a symbol. One of @code{'pool},
19647 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
19649 @item @code{address}
19650 The address of the server, as a string.
19652 @item @code{options}
19653 NTPD options to use with that specific server, given as a list of option names
19654 and/or of option names and values tuples. The following example define a server
19655 to use with the options @option{iburst} and @option{prefer}, as well as
19656 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
19661 (address "some.ntp.server.org")
19662 (options `(iburst (version 3) (maxpoll 16) prefer))))
19668 @deffn {Scheme Procedure} openntpd-service-type
19669 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
19670 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
19671 clock synchronized with that of the given servers.
19675 openntpd-service-type
19676 (openntpd-configuration
19677 (listen-on '("127.0.0.1" "::1"))
19678 (sensor '("udcf0 correction 70000"))
19679 (constraint-from '("www.gnu.org"))
19680 (constraints-from '("https://www.google.com/"))))
19685 @defvr {Scheme Variable} %openntpd-servers
19686 This variable is a list of the server addresses defined in
19687 @code{%ntp-servers}.
19690 @deftp {Data Type} openntpd-configuration
19692 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
19693 The openntpd executable to use.
19694 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
19695 A list of local IP addresses or hostnames the ntpd daemon should listen on.
19696 @item @code{query-from} (default: @code{'()})
19697 A list of local IP address the ntpd daemon should use for outgoing queries.
19698 @item @code{sensor} (default: @code{'()})
19699 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
19700 will listen to each sensor that actually exists and ignore non-existent ones.
19701 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
19703 @item @code{server} (default: @code{'()})
19704 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
19705 @item @code{servers} (default: @code{%openntp-servers})
19706 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
19707 @item @code{constraint-from} (default: @code{'()})
19708 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
19709 This time information is not used for precision but acts as an authenticated
19710 constraint, thereby reducing the impact of unauthenticated NTP
19711 man-in-the-middle attacks.
19712 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
19714 @item @code{constraints-from} (default: @code{'()})
19715 As with constraint from, specify a list of URLs, IP addresses or hostnames of
19716 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
19717 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
19722 @deffn {Scheme variable} inetd-service-type
19723 This service runs the @command{inetd} (@pxref{inetd invocation,,,
19724 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
19725 connections on internet sockets, and lazily starts the specified server
19726 program when a connection is made on one of these sockets.
19728 The value of this service is an @code{inetd-configuration} object. The
19729 following example configures the @command{inetd} daemon to provide the
19730 built-in @command{echo} service, as well as an smtp service which
19731 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
19732 gateway @code{hostname}:
19737 (inetd-configuration
19741 (socket-type 'stream)
19748 (socket-type 'stream)
19752 (program (file-append openssh "/bin/ssh"))
19754 '("ssh" "-qT" "-i" "/path/to/ssh_key"
19755 "-W" "smtp-server:25" "user@@hostname")))))))
19758 See below for more details about @code{inetd-configuration}.
19761 @deftp {Data Type} inetd-configuration
19762 Data type representing the configuration of @command{inetd}.
19765 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
19766 The @command{inetd} executable to use.
19768 @item @code{entries} (default: @code{'()})
19769 A list of @command{inetd} service entries. Each entry should be created
19770 by the @code{inetd-entry} constructor.
19774 @deftp {Data Type} inetd-entry
19775 Data type representing an entry in the @command{inetd} configuration.
19776 Each entry corresponds to a socket where @command{inetd} will listen for
19780 @item @code{node} (default: @code{#f})
19781 Optional string, a comma-separated list of local addresses
19782 @command{inetd} should use when listening for this service.
19783 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
19784 description of all options.
19786 A string, the name must correspond to an entry in @code{/etc/services}.
19787 @item @code{socket-type}
19788 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
19790 @item @code{protocol}
19791 A string, must correspond to an entry in @code{/etc/protocols}.
19792 @item @code{wait?} (default: @code{#t})
19793 Whether @command{inetd} should wait for the server to exit before
19794 listening to new service requests.
19796 A string containing the user (and, optionally, group) name of the user
19797 as whom the server should run. The group name can be specified in a
19798 suffix, separated by a colon or period, i.e.@: @code{"user"},
19799 @code{"user:group"} or @code{"user.group"}.
19800 @item @code{program} (default: @code{"internal"})
19801 The server program which will serve the requests, or @code{"internal"}
19802 if @command{inetd} should use a built-in service.
19803 @item @code{arguments} (default: @code{'()})
19804 A list strings or file-like objects, which are the server program's
19805 arguments, starting with the zeroth argument, i.e.@: the name of the
19806 program itself. For @command{inetd}'s internal services, this entry
19807 must be @code{'()} or @code{'("internal")}.
19810 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
19811 detailed discussion of each configuration field.
19814 @cindex opendht, distributed hash table network service
19815 @cindex dhtproxy, for use with jami
19816 @defvr {Scheme Variable} opendht-service-type
19817 This is the type of the service running a @uref{https://opendht.net,
19818 OpenDHT} node, @command{dhtnode}. The daemon can be used to host your
19819 own proxy service to the distributed hash table (DHT), for example to
19820 connect to with Jami, among other applications.
19822 @quotation Important
19823 When using the OpenDHT proxy server, the IP addresses it ``sees'' from
19824 the clients should be addresses reachable from other peers. In practice
19825 this means that a publicly reachable address is best suited for a proxy
19826 server, outside of your private network. For example, hosting the proxy
19827 server on a IPv4 private local network and exposing it via port
19828 forwarding could work for external peers, but peers local to the proxy
19829 would have their private addresses shared with the external peers,
19830 leading to connectivity problems.
19833 The value of this service is a @code{opendht-configuration} object, as
19837 @c The fields documentation has been auto-generated using the
19838 @c configuration->documentation procedure from
19839 @c (gnu services configuration).
19840 @deftp {Data Type} opendht-configuration
19841 Available @code{opendht-configuration} fields are:
19844 @item @code{opendht} (default: @code{opendht}) (type: file-like)
19845 The @code{opendht} package to use.
19847 @item @code{peer-discovery?} (default: @code{#f}) (type: boolean)
19848 Whether to enable the multicast local peer discovery mechanism.
19850 @item @code{enable-logging?} (default: @code{#f}) (type: boolean)
19851 Whether to enable logging messages to syslog. It is disabled by default
19852 as it is rather verbose.
19854 @item @code{debug?} (default: @code{#f}) (type: boolean)
19855 Whether to enable debug-level logging messages. This has no effect if
19856 logging is disabled.
19858 @item @code{bootstrap-host} (default: @code{"bootstrap.jami.net:4222"}) (type: maybe-string)
19859 The node host name that is used to make the first connection to the
19860 network. A specific port value can be provided by appending the
19861 @code{:PORT} suffix. By default, it uses the Jami bootstrap nodes, but
19862 any host can be specified here. It's also possible to disable
19863 bootstrapping by explicitly setting this field to the
19864 @code{%unset-value} value.
19866 @item @code{port} (default: @code{4222}) (type: maybe-number)
19867 The UDP port to bind to. When left unspecified, an available port is
19868 automatically selected.
19870 @item @code{proxy-server-port} (type: maybe-number)
19871 Spawn a proxy server listening on the specified port.
19873 @item @code{proxy-server-port-tls} (type: maybe-number)
19874 Spawn a proxy server listening to TLS connections on the specified port.
19880 @defvr {Scheme Variable} tor-service-type
19881 This is the type for a service that runs the @uref{https://torproject.org,
19882 Tor} anonymous networking daemon. The service is configured using a
19883 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
19884 @code{tor} unprivileged user, which is a member of the @code{tor} group.
19888 @deftp {Data Type} tor-configuration
19890 @item @code{tor} (default: @code{tor})
19891 The package that provides the Tor daemon. This package is expected to provide
19892 the daemon at @file{bin/tor} relative to its output directory. The default
19893 package is the @uref{https://www.torproject.org, Tor Project's}
19896 @item @code{config-file} (default: @code{(plain-file "empty" "")})
19897 The configuration file to use. It will be appended to a default configuration
19898 file, and the final configuration file will be passed to @code{tor} via its
19899 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
19900 file-like objects}). See @code{man tor} for details on the configuration file
19903 @item @code{hidden-services} (default: @code{'()})
19904 The list of @code{<hidden-service>} records to use. For any hidden service
19905 you include in this list, appropriate configuration to enable the hidden
19906 service will be automatically added to the default configuration file. You
19907 may conveniently create @code{<hidden-service>} records using the
19908 @code{tor-hidden-service} procedure described below.
19910 @item @code{socks-socket-type} (default: @code{'tcp})
19911 The default socket type that Tor should use for its SOCKS socket. This must
19912 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
19913 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
19914 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
19915 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
19918 If you want to customize the SOCKS socket in more detail, leave
19919 @code{socks-socket-type} at its default value of @code{'tcp} and use
19920 @code{config-file} to override the default by providing your own
19921 @code{SocksPort} option.
19923 @item @code{control-socket?} (default: @code{#f})
19924 Whether or not to provide a ``control socket'' by which Tor can be
19925 controlled to, for instance, dynamically instantiate tor onion services.
19926 If @code{#t}, Tor will listen for control commands on the UNIX domain socket
19927 @file{/var/run/tor/control-sock}, which will be made writable by members of the
19933 @cindex hidden service
19934 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
19935 Define a new Tor @dfn{hidden service} called @var{name} and implementing
19936 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
19939 '((22 "127.0.0.1:22")
19940 (80 "127.0.0.1:8080"))
19943 In this example, port 22 of the hidden service is mapped to local port 22, and
19944 port 80 is mapped to local port 8080.
19946 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
19947 the @file{hostname} file contains the @code{.onion} host name for the hidden
19950 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
19951 project's documentation} for more information.
19954 The @code{(gnu services rsync)} module provides the following services:
19956 You might want an rsync daemon if you have files that you want available
19957 so anyone (or just yourself) can download existing files or upload new
19960 @deffn {Scheme Variable} rsync-service-type
19961 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
19962 The value for this service type is a
19963 @command{rsync-configuration} record as in this example:
19966 ;; Export two directories over rsync. By default rsync listens on
19967 ;; all the network interfaces.
19968 (service rsync-service-type
19969 (rsync-configuration
19970 (modules (list (rsync-module
19972 (file-name "/srv/zik")
19976 (file-name "/home/charlie/movies"))))))
19979 See below for details about @code{rsync-configuration}.
19982 @deftp {Data Type} rsync-configuration
19983 Data type representing the configuration for @code{rsync-service}.
19986 @item @code{package} (default: @var{rsync})
19987 @code{rsync} package to use.
19989 @item @code{address} (default: @code{#f})
19990 IP address on which @command{rsync} listens for incoming connections.
19991 If unspecified, it defaults to listening on all available addresses.
19993 @item @code{port-number} (default: @code{873})
19994 TCP port on which @command{rsync} listens for incoming connections. If port
19995 is less than @code{1024} @command{rsync} needs to be started as the
19996 @code{root} user and group.
19998 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
19999 Name of the file where @command{rsync} writes its PID.
20001 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
20002 Name of the file where @command{rsync} writes its lock file.
20004 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
20005 Name of the file where @command{rsync} writes its log file.
20007 @item @code{user} (default: @code{"root"})
20008 Owner of the @code{rsync} process.
20010 @item @code{group} (default: @code{"root"})
20011 Group of the @code{rsync} process.
20013 @item @code{uid} (default: @code{"rsyncd"})
20014 User name or user ID that file transfers to and from that module should take
20015 place as when the daemon was run as @code{root}.
20017 @item @code{gid} (default: @code{"rsyncd"})
20018 Group name or group ID that will be used when accessing the module.
20020 @item @code{modules} (default: @code{%default-modules})
20021 List of ``modules''---i.e., directories exported over rsync. Each
20022 element must be a @code{rsync-module} record, as described below.
20026 @deftp {Data Type} rsync-module
20027 This is the data type for rsync ``modules''. A module is a directory
20028 exported over the rsync protocol. The available fields are as follows:
20032 The module name. This is the name that shows up in URLs. For example,
20033 if the module is called @code{music}, the corresponding URL will be
20034 @code{rsync://host.example.org/music}.
20036 @item @code{file-name}
20037 Name of the directory being exported.
20039 @item @code{comment} (default: @code{""})
20040 Comment associated with the module. Client user interfaces may display
20041 it when they obtain the list of available modules.
20043 @item @code{read-only?} (default: @code{#t})
20044 Whether or not client will be able to upload files. If this is false,
20045 the uploads will be authorized if permissions on the daemon side permit
20048 @item @code{chroot?} (default: @code{#t})
20049 When this is true, the rsync daemon changes root to the module's
20050 directory before starting file transfers with the client. This improves
20051 security, but requires rsync to run as root.
20053 @item @code{timeout} (default: @code{300})
20054 Idle time in seconds after which the daemon closes a connection with the
20059 The @code{(gnu services syncthing)} module provides the following services:
20062 You might want a syncthing daemon if you have files between two or more
20063 computers and want to sync them in real time, safely protected from
20066 @deffn {Scheme Variable} syncthing-service-type
20067 This is the service type for the @uref{https://syncthing.net/,
20068 syncthing} daemon, The value for this service type is a
20069 @command{syncthing-configuration} record as in this example:
20072 (service syncthing-service-type
20073 (syncthing-configuration (user "alice")))
20076 See below for details about @code{syncthing-configuration}.
20078 @deftp {Data Type} syncthing-configuration
20079 Data type representing the configuration for @code{syncthing-service-type}.
20082 @item @code{syncthing} (default: @var{syncthing})
20083 @code{syncthing} package to use.
20085 @item @code{arguments} (default: @var{'()})
20086 List of command-line arguments passing to @code{syncthing} binary.
20088 @item @code{logflags} (default: @var{0})
20089 Sum of logging flags, see
20090 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
20092 @item @code{user} (default: @var{#f})
20093 The user as which the Syncthing service is to be run.
20094 This assumes that the specified user exists.
20096 @item @code{group} (default: @var{"users"})
20097 The group as which the Syncthing service is to be run.
20098 This assumes that the specified group exists.
20100 @item @code{home} (default: @var{#f})
20101 Common configuration and data directory. The default configuration
20102 directory is @file{$HOME} of the specified Syncthing @code{user}.
20108 Furthermore, @code{(gnu services ssh)} provides the following services.
20112 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
20113 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
20114 [#:allow-empty-passwords? #f] [#:root-login? #f] @
20115 [#:syslog-output? #t] [#:x11-forwarding? #t] @
20116 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
20117 [#:public-key-authentication? #t] [#:initialize? #t]
20118 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
20119 @var{host-key} must designate a file containing the host key, and readable
20122 When @var{daemonic?} is true, @command{lshd} will detach from the
20123 controlling terminal and log its output to syslogd, unless one sets
20124 @var{syslog-output?} to false. Obviously, it also makes lsh-service
20125 depend on existence of syslogd service. When @var{pid-file?} is true,
20126 @command{lshd} writes its PID to the file called @var{pid-file}.
20128 When @var{initialize?} is true, automatically create the seed and host key
20129 upon service activation if they do not exist yet. This may take long and
20130 require interaction.
20132 When @var{initialize?} is false, it is up to the user to initialize the
20133 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
20134 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
20135 basics,,, lsh, LSH Manual}).
20137 When @var{interfaces} is empty, lshd listens for connections on all the
20138 network interfaces; otherwise, @var{interfaces} must be a list of host names
20141 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
20142 passwords, and @var{root-login?} specifies whether to accept log-ins as
20145 The other options should be self-descriptive.
20150 @deffn {Scheme Variable} openssh-service-type
20151 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
20152 shell daemon, @command{sshd}. Its value must be an
20153 @code{openssh-configuration} record as in this example:
20156 (service openssh-service-type
20157 (openssh-configuration
20158 (x11-forwarding? #t)
20159 (permit-root-login 'prohibit-password)
20161 `(("alice" ,(local-file "alice.pub"))
20162 ("bob" ,(local-file "bob.pub"))))))
20165 See below for details about @code{openssh-configuration}.
20167 This service can be extended with extra authorized keys, as in this
20171 (service-extension openssh-service-type
20172 (const `(("charlie"
20173 ,(local-file "charlie.pub")))))
20177 @deftp {Data Type} openssh-configuration
20178 This is the configuration record for OpenSSH's @command{sshd}.
20181 @item @code{openssh} (default @var{openssh})
20182 The OpenSSH package to use.
20184 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
20185 Name of the file where @command{sshd} writes its PID.
20187 @item @code{port-number} (default: @code{22})
20188 TCP port on which @command{sshd} listens for incoming connections.
20190 @item @code{max-connections} (default: @code{200})
20191 Hard limit on the maximum number of simultaneous client connections,
20192 enforced by the inetd-style Shepherd service (@pxref{Service De- and
20193 Constructors, @code{make-inetd-constructor},, shepherd, The GNU Shepherd
20196 @item @code{permit-root-login} (default: @code{#f})
20197 This field determines whether and when to allow logins as root. If
20198 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
20199 If it's the symbol @code{'prohibit-password}, then root logins are
20200 permitted but not with password-based authentication.
20202 @item @code{allow-empty-passwords?} (default: @code{#f})
20203 When true, users with empty passwords may log in. When false, they may
20206 @item @code{password-authentication?} (default: @code{#t})
20207 When true, users may log in with their password. When false, they have
20208 other authentication methods.
20210 @item @code{public-key-authentication?} (default: @code{#t})
20211 When true, users may log in using public key authentication. When
20212 false, users have to use other authentication method.
20214 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
20215 This is used only by protocol version 2.
20217 @item @code{x11-forwarding?} (default: @code{#f})
20218 When true, forwarding of X11 graphical client connections is
20219 enabled---in other words, @command{ssh} options @option{-X} and
20220 @option{-Y} will work.
20222 @item @code{allow-agent-forwarding?} (default: @code{#t})
20223 Whether to allow agent forwarding.
20225 @item @code{allow-tcp-forwarding?} (default: @code{#t})
20226 Whether to allow TCP forwarding.
20228 @item @code{gateway-ports?} (default: @code{#f})
20229 Whether to allow gateway ports.
20231 @item @code{challenge-response-authentication?} (default: @code{#f})
20232 Specifies whether challenge response authentication is allowed (e.g.@: via
20235 @item @code{use-pam?} (default: @code{#t})
20236 Enables the Pluggable Authentication Module interface. If set to
20237 @code{#t}, this will enable PAM authentication using
20238 @code{challenge-response-authentication?} and
20239 @code{password-authentication?}, in addition to PAM account and session
20240 module processing for all authentication types.
20242 Because PAM challenge response authentication usually serves an
20243 equivalent role to password authentication, you should disable either
20244 @code{challenge-response-authentication?} or
20245 @code{password-authentication?}.
20247 @item @code{print-last-log?} (default: @code{#t})
20248 Specifies whether @command{sshd} should print the date and time of the
20249 last user login when a user logs in interactively.
20251 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
20252 Configures external subsystems (e.g.@: file transfer daemon).
20254 This is a list of two-element lists, each of which containing the
20255 subsystem name and a command (with optional arguments) to execute upon
20258 The command @command{internal-sftp} implements an in-process SFTP
20259 server. Alternatively, one can specify the @command{sftp-server} command:
20261 (service openssh-service-type
20262 (openssh-configuration
20264 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
20267 @item @code{accepted-environment} (default: @code{'()})
20268 List of strings describing which environment variables may be exported.
20270 Each string gets on its own line. See the @code{AcceptEnv} option in
20271 @code{man sshd_config}.
20273 This example allows ssh-clients to export the @env{COLORTERM} variable.
20274 It is set by terminal emulators, which support colors. You can use it in
20275 your shell's resource file to enable colors for the prompt and commands
20276 if this variable is set.
20279 (service openssh-service-type
20280 (openssh-configuration
20281 (accepted-environment '("COLORTERM"))))
20284 @item @code{authorized-keys} (default: @code{'()})
20285 @cindex authorized keys, SSH
20286 @cindex SSH authorized keys
20287 This is the list of authorized keys. Each element of the list is a user
20288 name followed by one or more file-like objects that represent SSH public
20292 (openssh-configuration
20294 `(("rekado" ,(local-file "rekado.pub"))
20295 ("chris" ,(local-file "chris.pub"))
20296 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
20300 registers the specified public keys for user accounts @code{rekado},
20301 @code{chris}, and @code{root}.
20303 Additional authorized keys can be specified @i{via}
20304 @code{service-extension}.
20306 Note that this does @emph{not} interfere with the use of
20307 @file{~/.ssh/authorized_keys}.
20309 @item @code{generate-host-keys?} (default: @code{#t})
20310 Whether to generate host key pairs with @command{ssh-keygen -A} under
20311 @file{/etc/ssh} if there are none.
20313 Generating key pairs takes a few seconds when enough entropy is
20314 available and is only done once. You might want to turn it off for
20315 instance in a virtual machine that does not need it because host keys
20316 are provided in some other way, and where the extra boot time is a
20319 @item @code{log-level} (default: @code{'info})
20320 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
20321 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
20322 page for @file{sshd_config} for the full list of level names.
20324 @item @code{extra-content} (default: @code{""})
20325 This field can be used to append arbitrary text to the configuration file. It
20326 is especially useful for elaborate configurations that cannot be expressed
20327 otherwise. This configuration, for example, would generally disable root
20328 logins, but permit them from one specific IP address:
20331 (openssh-configuration
20333 Match Address 192.168.0.1
20334 PermitRootLogin yes"))
20340 @deffn {Scheme Procedure} dropbear-service [@var{config}]
20341 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
20342 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
20345 For example, to specify a Dropbear service listening on port 1234, add
20346 this call to the operating system's @code{services} field:
20349 (dropbear-service (dropbear-configuration
20350 (port-number 1234)))
20354 @deftp {Data Type} dropbear-configuration
20355 This data type represents the configuration of a Dropbear SSH daemon.
20358 @item @code{dropbear} (default: @var{dropbear})
20359 The Dropbear package to use.
20361 @item @code{port-number} (default: 22)
20362 The TCP port where the daemon waits for incoming connections.
20364 @item @code{syslog-output?} (default: @code{#t})
20365 Whether to enable syslog output.
20367 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
20368 File name of the daemon's PID file.
20370 @item @code{root-login?} (default: @code{#f})
20371 Whether to allow @code{root} logins.
20373 @item @code{allow-empty-passwords?} (default: @code{#f})
20374 Whether to allow empty passwords.
20376 @item @code{password-authentication?} (default: @code{#t})
20377 Whether to enable password-based authentication.
20382 @deffn {Scheme Variable} autossh-service-type
20383 This is the type for the @uref{https://www.harding.motd.ca/autossh,
20384 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
20385 restarting it as necessary should it die or stop passing traffic.
20386 AutoSSH can be run manually from the command-line by passing arguments
20387 to the binary @command{autossh} from the package @code{autossh}, but it
20388 can also be run as a Guix service. This latter use case is documented
20391 AutoSSH can be used to forward local traffic to a remote machine using
20392 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
20395 For example, to specify a service running autossh as the user
20396 @code{pino} and forwarding all local connections to port @code{8081} to
20397 @code{remote:8081} using an SSH tunnel, add this call to the operating
20398 system's @code{services} field:
20401 (service autossh-service-type
20402 (autossh-configuration
20404 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
20408 @deftp {Data Type} autossh-configuration
20409 This data type represents the configuration of an AutoSSH service.
20413 @item @code{user} (default @code{"autossh"})
20414 The user as which the AutoSSH service is to be run.
20415 This assumes that the specified user exists.
20417 @item @code{poll} (default @code{600})
20418 Specifies the connection poll time in seconds.
20420 @item @code{first-poll} (default @code{#f})
20421 Specifies how many seconds AutoSSH waits before the first connection
20422 test. After this first test, polling is resumed at the pace defined in
20423 @code{poll}. When set to @code{#f}, the first poll is not treated
20424 specially and will also use the connection poll specified in
20427 @item @code{gate-time} (default @code{30})
20428 Specifies how many seconds an SSH connection must be active before it is
20429 considered successful.
20431 @item @code{log-level} (default @code{1})
20432 The log level, corresponding to the levels used by syslog---so @code{0}
20433 is the most silent while @code{7} is the chattiest.
20435 @item @code{max-start} (default @code{#f})
20436 The maximum number of times SSH may be (re)started before AutoSSH exits.
20437 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
20439 @item @code{message} (default @code{""})
20440 The message to append to the echo message sent when testing connections.
20442 @item @code{port} (default @code{"0"})
20443 The ports used for monitoring the connection. When set to @code{"0"},
20444 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
20445 a positive integer, ports @var{n} and @var{n}+1 are used for
20446 monitoring the connection, such that port @var{n} is the base
20447 monitoring port and @code{n+1} is the echo port. When set to
20448 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
20449 integers, the ports @var{n} and @var{m} are used for monitoring the
20450 connection, such that port @var{n} is the base monitoring port and
20451 @var{m} is the echo port.
20453 @item @code{ssh-options} (default @code{'()})
20454 The list of command-line arguments to pass to @command{ssh} when it is
20455 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
20456 may cause undefined behaviour.
20462 @deffn {Scheme Variable} webssh-service-type
20463 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
20464 program that runs a web SSH client. WebSSH can be run manually from the
20465 command-line by passing arguments to the binary @command{wssh} from the
20466 package @code{webssh}, but it can also be run as a Guix service. This
20467 latter use case is documented here.
20469 For example, to specify a service running WebSSH on loopback interface
20470 on port @code{8888} with reject policy with a list of allowed to
20471 connection hosts, and NGINX as a reverse-proxy to this service listening
20472 for HTTPS connection, add this call to the operating system's
20473 @code{services} field:
20476 (service webssh-service-type
20477 (webssh-configuration (address "127.0.0.1")
20480 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
20481 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
20483 (service nginx-service-type
20484 (nginx-configuration
20487 (nginx-server-configuration
20488 (inherit %webssh-configuration-nginx)
20489 (server-name '("webssh.example.com"))
20490 (listen '("443 ssl"))
20491 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
20492 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
20494 (cons (nginx-location-configuration
20495 (uri "/.well-known")
20496 (body '("root /var/www;")))
20497 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
20501 @deftp {Data Type} webssh-configuration
20502 Data type representing the configuration for @code{webssh-service}.
20505 @item @code{package} (default: @var{webssh})
20506 @code{webssh} package to use.
20508 @item @code{user-name} (default: @var{"webssh"})
20509 User name or user ID that file transfers to and from that module should take
20512 @item @code{group-name} (default: @var{"webssh"})
20513 Group name or group ID that will be used when accessing the module.
20515 @item @code{address} (default: @var{#f})
20516 IP address on which @command{webssh} listens for incoming connections.
20518 @item @code{port} (default: @var{8888})
20519 TCP port on which @command{webssh} listens for incoming connections.
20521 @item @code{policy} (default: @var{#f})
20522 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
20524 @item @code{known-hosts} (default: @var{'()})
20525 List of hosts which allowed for SSH connection from @command{webssh}.
20527 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
20528 Name of the file where @command{webssh} writes its log file.
20530 @item @code{log-level} (default: @var{#f})
20536 @defvr {Scheme Variable} %facebook-host-aliases
20537 This variable contains a string for use in @file{/etc/hosts}
20538 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
20539 line contains a entry that maps a known server name of the Facebook
20540 on-line service---e.g., @code{www.facebook.com}---to the local
20541 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
20543 This variable is typically used in the @code{hosts-file} field of an
20544 @code{operating-system} declaration (@pxref{operating-system Reference,
20545 @file{/etc/hosts}}):
20548 (use-modules (gnu) (guix))
20551 (host-name "mymachine")
20554 ;; Create a /etc/hosts file with aliases for "localhost"
20555 ;; and "mymachine", as well as for Facebook servers.
20556 (plain-file "hosts"
20557 (string-append (local-host-aliases host-name)
20558 %facebook-host-aliases))))
20561 This mechanism can prevent programs running locally, such as Web
20562 browsers, from accessing Facebook.
20565 The @code{(gnu services avahi)} provides the following definition.
20567 @defvr {Scheme Variable} avahi-service-type
20568 This is the service that runs @command{avahi-daemon}, a system-wide
20569 mDNS/DNS-SD responder that allows for service discovery and
20570 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
20571 Its value must be an @code{avahi-configuration} record---see below.
20573 This service extends the name service cache daemon (nscd) so that it can
20574 resolve @code{.local} host names using
20575 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
20576 Service Switch}, for information on host name resolution.
20578 Additionally, add the @var{avahi} package to the system profile so that
20579 commands such as @command{avahi-browse} are directly usable.
20582 @deftp {Data Type} avahi-configuration
20583 Data type representation the configuration for Avahi.
20587 @item @code{host-name} (default: @code{#f})
20588 If different from @code{#f}, use that as the host name to
20589 publish for this machine; otherwise, use the machine's actual host name.
20591 @item @code{publish?} (default: @code{#t})
20592 When true, allow host names and services to be published (broadcast) over the
20595 @item @code{publish-workstation?} (default: @code{#t})
20596 When true, @command{avahi-daemon} publishes the machine's host name and IP
20597 address via mDNS on the local network. To view the host names published on
20598 your local network, you can run:
20601 avahi-browse _workstation._tcp
20604 @item @code{wide-area?} (default: @code{#f})
20605 When true, DNS-SD over unicast DNS is enabled.
20607 @item @code{ipv4?} (default: @code{#t})
20608 @itemx @code{ipv6?} (default: @code{#t})
20609 These fields determine whether to use IPv4/IPv6 sockets.
20611 @item @code{domains-to-browse} (default: @code{'()})
20612 This is a list of domains to browse.
20616 @deffn {Scheme Variable} openvswitch-service-type
20617 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
20618 service, whose value should be an @code{openvswitch-configuration}
20622 @deftp {Data Type} openvswitch-configuration
20623 Data type representing the configuration of Open vSwitch, a multilayer
20624 virtual switch which is designed to enable massive network automation
20625 through programmatic extension.
20628 @item @code{package} (default: @var{openvswitch})
20629 Package object of the Open vSwitch.
20634 @defvr {Scheme Variable} pagekite-service-type
20635 This is the service type for the @uref{https://pagekite.net, PageKite} service,
20636 a tunneling solution for making localhost servers publicly visible, even from
20637 behind restrictive firewalls or NAT without forwarded ports. The value for
20638 this service type is a @code{pagekite-configuration} record.
20640 Here's an example exposing the local HTTP and SSH daemons:
20643 (service pagekite-service-type
20644 (pagekite-configuration
20645 (kites '("http:@@kitename:localhost:80:@@kitesecret"
20646 "raw/22:@@kitename:localhost:22:@@kitesecret"))
20647 (extra-file "/etc/pagekite.rc")))
20651 @deftp {Data Type} pagekite-configuration
20652 Data type representing the configuration of PageKite.
20655 @item @code{package} (default: @var{pagekite})
20656 Package object of PageKite.
20658 @item @code{kitename} (default: @code{#f})
20659 PageKite name for authenticating to the frontend server.
20661 @item @code{kitesecret} (default: @code{#f})
20662 Shared secret for authenticating to the frontend server. You should probably
20663 put this inside @code{extra-file} instead.
20665 @item @code{frontend} (default: @code{#f})
20666 Connect to the named PageKite frontend server instead of the
20667 @uref{https://pagekite.net,,pagekite.net} service.
20669 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
20670 List of service kites to use. Exposes HTTP on port 80 by default. The format
20671 is @code{proto:kitename:host:port:secret}.
20673 @item @code{extra-file} (default: @code{#f})
20674 Extra configuration file to read, which you are expected to create manually.
20675 Use this to add additional options and manage shared secrets out-of-band.
20680 @defvr {Scheme Variable} yggdrasil-service-type
20681 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
20682 Yggdrasil network}, an early-stage implementation of a fully end-to-end
20683 encrypted IPv6 network.
20686 Yggdrasil provides name-independent routing with cryptographically generated
20687 addresses. Static addressing means you can keep the same address as long as
20688 you want, even if you move to a new location, or generate a new address (by
20689 generating new keys) whenever you want.
20690 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
20693 Pass it a value of @code{yggdrasil-configuration} to connect it to public
20694 peers and/or local peers.
20696 Here is an example using public peers and a static address. The static
20697 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
20698 (the default value for @code{config-file}).
20701 ;; part of the operating-system declaration
20702 (service yggdrasil-service-type
20703 (yggdrasil-configuration
20704 (autoconf? #f) ;; use only the public peers
20707 ;; https://github.com/yggdrasil-network/public-peers
20708 '((peers . #("tcp://1.2.3.4:1337"))))
20709 ;; /etc/yggdrasil-private.conf is the default value for config-file
20713 # sample content for /etc/yggdrasil-private.conf
20715 # Your public key. Your peers may ask you for this to put
20716 # into their AllowedPublicKeys configuration.
20717 PublicKey: 64277...
20719 # Your private key. DO NOT share this with anyone!
20720 PrivateKey: 5c750...
20725 @deftp {Data Type} yggdrasil-configuration
20726 Data type representing the configuration of Yggdrasil.
20729 @item @code{package} (default: @code{yggdrasil})
20730 Package object of Yggdrasil.
20732 @item @code{json-config} (default: @code{'()})
20733 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
20734 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
20735 the Guix store, which is readable to all users. @strong{Do not store your
20736 private keys in it}. See the output of @code{yggdrasil -genconf} for a
20737 quick overview of valid keys and their default values.
20739 @item @code{autoconf?} (default: @code{#f})
20740 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
20741 and peer with IPv6 neighbors.
20743 @item @code{log-level} (default: @code{'info})
20744 How much detail to include in logs. Use @code{'debug} for more detail.
20746 @item @code{log-to} (default: @code{'stdout})
20747 Where to send logs. By default, the service logs standard output to
20748 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
20749 sends output to the running syslog service.
20751 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
20752 What HJSON file to load sensitive data from. This is where private keys
20753 should be stored, which are necessary to specify if you don't want a
20754 randomized address after each restart. Use @code{#f} to disable. Options
20755 defined in this file take precedence over @code{json-config}. Use the output
20756 of @code{yggdrasil -genconf} as a starting point. To configure a static
20757 address, delete everything except these options:
20760 @item @code{EncryptionPublicKey}
20761 @item @code{EncryptionPrivateKey}
20762 @item @code{SigningPublicKey}
20763 @item @code{SigningPrivateKey}
20769 @defvr {Scheme Variable} ipfs-service-type
20770 The service type for connecting to the @uref{https://ipfs.io,IPFS network},
20771 a global, versioned, peer-to-peer file system. Pass it a
20772 @code{ipfs-configuration} to change the ports used for the gateway and API.
20774 Here's an example configuration, using some non-standard ports:
20777 (service ipfs-service-type
20778 (ipfs-configuration
20779 (gateway "/ip4/127.0.0.1/tcp/8880")
20780 (api "/ip4/127.0.0.1/tcp/8881")))
20784 @deftp {Data Type} ipfs-configuration
20785 Data type representing the configuration of IPFS.
20788 @item @code{package} (default: @code{go-ipfs})
20789 Package object of IPFS.
20791 @item @code{gateway} (default: @code{"/ip4/127.0.0.1/tcp/8082"})
20792 Address of the gateway, in ‘multiaddress’ format.
20794 @item @code{api} (default: @code{"/ip4/127.0.0.1/tcp/5001"})
20795 Address of the API endpoint, in ‘multiaddress’ format.
20800 @deffn {Scheme Variable} keepalived-service-type
20801 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
20802 routing software, @command{keepalived}. Its value must be an
20803 @code{keepalived-configuration} record as in this example for master
20807 (service keepalived-service-type
20808 (keepalived-configuration
20809 (config-file (local-file "keepalived-master.conf"))))
20812 where @file{keepalived-master.conf}:
20815 vrrp_instance my-group @{
20818 virtual_router_id 100
20820 unicast_peer @{ 10.0.0.2 @}
20821 virtual_ipaddress @{
20827 and for backup machine:
20830 (service keepalived-service-type
20831 (keepalived-configuration
20832 (config-file (local-file "keepalived-backup.conf"))))
20835 where @file{keepalived-backup.conf}:
20838 vrrp_instance my-group @{
20841 virtual_router_id 100
20843 unicast_peer @{ 10.0.0.3 @}
20844 virtual_ipaddress @{
20851 @node Unattended Upgrades
20852 @subsection Unattended Upgrades
20854 @cindex unattended upgrades
20855 @cindex upgrades, unattended
20856 Guix provides a service to perform @emph{unattended upgrades}:
20857 periodically, the system automatically reconfigures itself from the
20858 latest Guix. Guix System has several properties that make unattended
20863 upgrades are transactional (either the upgrade succeeds or it fails, but
20864 you cannot end up with an ``in-between'' system state);
20866 the upgrade log is kept---you can view it with @command{guix system
20867 list-generations}---and you can roll back to any previous generation,
20868 should the upgraded system fail to behave as intended;
20870 channel code is authenticated so you know you can only run genuine code
20871 (@pxref{Channels});
20873 @command{guix system reconfigure} prevents downgrades, which makes it
20874 immune to @dfn{downgrade attacks}.
20877 To set up unattended upgrades, add an instance of
20878 @code{unattended-upgrade-service-type} like the one below to the list of
20879 your operating system services:
20882 (service unattended-upgrade-service-type)
20885 The defaults above set up weekly upgrades: every Sunday at midnight.
20886 You do not need to provide the operating system configuration file: it
20887 uses @file{/run/current-system/configuration.scm}, which ensures it
20888 always uses your latest configuration---@pxref{provenance-service-type},
20889 for more information about this file.
20891 There are several things that can be configured, in particular the
20892 periodicity and services (daemons) to be restarted upon completion.
20893 When the upgrade is successful, the service takes care of deleting
20894 system generations older that some threshold, as per @command{guix
20895 system delete-generations}. See the reference below for details.
20897 To ensure that upgrades are actually happening, you can run
20898 @command{guix system describe}. To investigate upgrade failures, visit
20899 the unattended upgrade log file (see below).
20901 @defvr {Scheme Variable} unattended-upgrade-service-type
20902 This is the service type for unattended upgrades. It sets up an mcron
20903 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
20904 reconfigure} from the latest version of the specified channels.
20906 Its value must be a @code{unattended-upgrade-configuration} record (see
20910 @deftp {Data Type} unattended-upgrade-configuration
20911 This data type represents the configuration of the unattended upgrade
20912 service. The following fields are available:
20915 @item @code{schedule} (default: @code{"30 01 * * 0"})
20916 This is the schedule of upgrades, expressed as a gexp containing an
20917 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
20918 mcron, GNU@tie{}mcron}).
20920 @item @code{channels} (default: @code{#~%default-channels})
20921 This gexp specifies the channels to use for the upgrade
20922 (@pxref{Channels}). By default, the tip of the official @code{guix}
20925 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
20926 This field specifies the operating system configuration file to use.
20927 The default is to reuse the config file of the current configuration.
20929 There are cases, though, where referring to
20930 @file{/run/current-system/configuration.scm} is not enough, for instance
20931 because that file refers to extra files (SSH public keys, extra
20932 configuration files, etc.) @i{via} @code{local-file} and similar
20933 constructs. For those cases, we recommend something along these lines:
20936 (unattended-upgrade-configuration
20937 (operating-system-file
20938 (file-append (local-file "." "config-dir" #:recursive? #t)
20942 The effect here is to import all of the current directory into the
20943 store, and to refer to @file{config.scm} within that directory.
20944 Therefore, uses of @code{local-file} within @file{config.scm} will work
20945 as expected. @xref{G-Expressions}, for information about
20946 @code{local-file} and @code{file-append}.
20948 @item @code{services-to-restart} (default: @code{'(mcron)})
20949 This field specifies the Shepherd services to restart when the upgrade
20952 Those services are restarted right away upon completion, as with
20953 @command{herd restart}, which ensures that the latest version is
20954 running---remember that by default @command{guix system reconfigure}
20955 only restarts services that are not currently running, which is
20956 conservative: it minimizes disruption but leaves outdated services
20959 Use @command{herd status} to find out candidates for restarting.
20960 @xref{Services}, for general information about services. Common
20961 services to restart would include @code{ntpd} and @code{ssh-daemon}.
20963 By default, the @code{mcron} service is restarted. This ensures that
20964 the latest version of the unattended upgrade job will be used next time.
20966 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
20967 This is the expiration time in seconds for system generations. System
20968 generations older that this amount of time are deleted with
20969 @command{guix system delete-generations} when an upgrade completes.
20972 The unattended upgrade service does not run the garbage collector. You
20973 will probably want to set up your own mcron job to run @command{guix gc}
20977 @item @code{maximum-duration} (default: @code{3600})
20978 Maximum duration in seconds for the upgrade; past that time, the upgrade
20981 This is primarily useful to ensure the upgrade does not end up
20982 rebuilding or re-downloading ``the world''.
20984 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
20985 File where unattended upgrades are logged.
20990 @subsection X Window
20993 @cindex X Window System
20994 @cindex login manager
20995 Support for the X Window graphical display system---specifically
20996 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
20997 there is no @code{xorg-service} procedure. Instead, the X server is
20998 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
21001 @cindex GNOME, login manager
21002 GDM of course allows users to log in into window managers and desktop
21003 environments other than GNOME; for those using GNOME, GDM is required for
21004 features such as automatic screen locking.
21006 @cindex window manager
21007 To use X11, you must install at least one @dfn{window manager}---for
21008 example the @code{windowmaker} or @code{openbox} packages---preferably
21009 by adding it to the @code{packages} field of your operating system
21010 definition (@pxref{operating-system Reference, system-wide packages}).
21012 @anchor{wayland-gdm}
21013 GDM also supports Wayland: it can itself use Wayland instead of X11 for
21014 its user interface, and it can also start Wayland sessions. The former is
21015 required for the latter, to enable, set @code{wayland?} to @code{#t} in
21016 @code{gdm-configuration}.
21018 @defvr {Scheme Variable} gdm-service-type
21019 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
21020 Desktop Manager} (GDM), a program that manages graphical display servers and
21021 handles graphical user logins. Its value must be a @code{gdm-configuration}
21024 @cindex session types
21025 GDM looks for @dfn{session types} described by the @file{.desktop} files in
21026 @file{/run/current-system/profile/share/xsessions} (for X11 sessions) and
21027 @file{/run/current-system/profile/share/wayland-sessions} (for Wayland
21028 sessions) and allows users to choose a session from the log-in screen.
21029 Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
21030 @file{.desktop} files; adding them to the system-wide set of packages
21031 automatically makes them available at the log-in screen.
21033 In addition, @file{~/.xsession} files are honored. When available,
21034 @file{~/.xsession} must be an executable that starts a window manager
21035 and/or other X clients.
21038 @deftp {Data Type} gdm-configuration
21040 @item @code{auto-login?} (default: @code{#f})
21041 @itemx @code{default-user} (default: @code{#f})
21042 When @code{auto-login?} is false, GDM presents a log-in screen.
21044 When @code{auto-login?} is true, GDM logs in directly as
21045 @code{default-user}.
21047 @item @code{debug?} (default: @code{#f})
21048 When true, GDM writes debug messages to its log.
21050 @item @code{gnome-shell-assets} (default: ...)
21051 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
21053 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
21054 Configuration of the Xorg graphical server.
21056 @item @code{x-session} (default: @code{(xinitrc)})
21057 Script to run before starting a X session.
21059 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
21060 File name of the @code{dbus-daemon} executable.
21062 @item @code{gdm} (default: @code{gdm})
21063 The GDM package to use.
21065 @item @code{wayland?} (default: @code{#f})
21066 When true, enables Wayland in GDM, necessary to use Wayland sessions.
21068 @item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
21069 The Wayland session wrapper to use, needed to setup the
21074 @defvr {Scheme Variable} slim-service-type
21075 This is the type for the SLiM graphical login manager for X11.
21077 Like GDM, SLiM looks for session types described by @file{.desktop} files and
21078 allows users to choose a session from the log-in screen using @kbd{F1}. It
21079 also honors @file{~/.xsession} files.
21081 Unlike GDM, SLiM does not spawn the user session on a different VT after
21082 logging in, which means that you can only start one graphical session. If you
21083 want to be able to run multiple graphical sessions at the same time you have
21084 to add multiple SLiM services to your system services. The following example
21085 shows how to replace the default GDM service with two SLiM services on tty7
21089 (use-modules (gnu services)
21090 (gnu services desktop)
21091 (gnu services xorg))
21095 (services (cons* (service slim-service-type (slim-configuration
21098 (service slim-service-type (slim-configuration
21101 (modify-services %desktop-services
21102 (delete gdm-service-type)))))
21107 @deftp {Data Type} slim-configuration
21108 Data type representing the configuration of @code{slim-service-type}.
21111 @item @code{allow-empty-passwords?} (default: @code{#t})
21112 Whether to allow logins with empty passwords.
21114 @item @code{gnupg?} (default: @code{#f})
21115 If enabled, @code{pam-gnupg} will attempt to automatically unlock the
21116 user's GPG keys with the login password via @code{gpg-agent}. The
21117 keygrips of all keys to be unlocked should be written to
21118 @file{~/.pam-gnupg}, and can be queried with @code{gpg -K
21119 --with-keygrip}. Presetting passphrases must be enabled by adding
21120 @code{allow-preset-passphrase} in @file{~/.gnupg/gpg-agent.conf}.
21122 @item @code{auto-login?} (default: @code{#f})
21123 @itemx @code{default-user} (default: @code{""})
21124 When @code{auto-login?} is false, SLiM presents a log-in screen.
21126 When @code{auto-login?} is true, SLiM logs in directly as
21127 @code{default-user}.
21129 @item @code{theme} (default: @code{%default-slim-theme})
21130 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
21131 The graphical theme to use and its name.
21133 @item @code{auto-login-session} (default: @code{#f})
21134 If true, this must be the name of the executable to start as the default
21135 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
21137 If false, a session described by one of the available @file{.desktop}
21138 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
21142 You must install at least one window manager in the system profile or in
21143 your user profile. Failing to do that, if @code{auto-login-session} is
21144 false, you will be unable to log in.
21147 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21148 Configuration of the Xorg graphical server.
21150 @item @code{display} (default @code{":0"})
21151 The display on which to start the Xorg graphical server.
21153 @item @code{vt} (default @code{"vt7"})
21154 The VT on which to start the Xorg graphical server.
21156 @item @code{xauth} (default: @code{xauth})
21157 The XAuth package to use.
21159 @item @code{shepherd} (default: @code{shepherd})
21160 The Shepherd package used when invoking @command{halt} and
21163 @item @code{sessreg} (default: @code{sessreg})
21164 The sessreg package used in order to register the session.
21166 @item @code{slim} (default: @code{slim})
21167 The SLiM package to use.
21171 @defvr {Scheme Variable} %default-theme
21172 @defvrx {Scheme Variable} %default-theme-name
21173 The default SLiM theme and its name.
21177 @cindex login manager
21179 @defvr {Scheme Variable} sddm-service-type
21180 This is the type of the service to run the
21181 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
21182 must be a @code{sddm-configuration} record (see below).
21184 Here's an example use:
21187 (service sddm-service-type
21188 (sddm-configuration
21189 (auto-login-user "alice")
21190 (auto-login-session "xfce.desktop")))
21194 @deftp {Data Type} sddm-configuration
21195 This data type represents the configuration of the SDDM login manager.
21196 The available fields are:
21199 @item @code{sddm} (default: @code{sddm})
21200 The SDDM package to use.
21202 @item @code{display-server} (default: "x11")
21203 Select display server to use for the greeter. Valid values are
21204 @samp{"x11"} or @samp{"wayland"}.
21206 @item @code{numlock} (default: "on")
21207 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
21209 @item @code{halt-command} (default @code{#~(string-append #$shepherd "/sbin/halt")})
21210 Command to run when halting.
21212 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
21213 Command to run when rebooting.
21215 @item @code{theme} (default "maldives")
21216 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
21217 @samp{"maldives"} or @samp{"maya"}.
21219 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
21220 Directory to look for themes.
21222 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
21223 Directory to look for faces.
21225 @item @code{default-path} (default "/run/current-system/profile/bin")
21226 Default PATH to use.
21228 @item @code{minimum-uid} (default: 1000)
21229 Minimum UID displayed in SDDM and allowed for log-in.
21231 @item @code{maximum-uid} (default: 2000)
21232 Maximum UID to display in SDDM.
21234 @item @code{remember-last-user?} (default #t)
21235 Remember last user.
21237 @item @code{remember-last-session?} (default #t)
21238 Remember last session.
21240 @item @code{hide-users} (default "")
21241 Usernames to hide from SDDM greeter.
21243 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
21244 Users with shells listed will be hidden from the SDDM greeter.
21246 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
21247 Script to run before starting a wayland session.
21249 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
21250 Directory to look for desktop files starting wayland sessions.
21252 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21253 Configuration of the Xorg graphical server.
21255 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
21258 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
21261 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
21262 Script to run after starting xorg-server.
21264 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
21265 Script to run before stopping xorg-server.
21267 @item @code{xsession-command} (default: @code{xinitrc})
21268 Script to run before starting a X session.
21270 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
21271 Directory to look for desktop files starting X sessions.
21273 @item @code{minimum-vt} (default: 7)
21276 @item @code{auto-login-user} (default "")
21277 User account that will be automatically logged in.
21278 Setting this to the empty string disables auto-login.
21280 @item @code{auto-login-session} (default "")
21281 The @file{.desktop} file name to use as the auto-login session, or the empty string.
21283 @item @code{relogin?} (default #f)
21284 Relogin after logout.
21289 @cindex lightdm, graphical login manager
21290 @cindex display manager, lightdm
21291 @defvr {Scheme Variable} lightdm-service-type
21292 This is the type of the service to run the
21293 @url{https://github.com/canonical/lightdm,LightDM display manager}. Its
21294 value must be a @code{lightdm-configuration} record, which is documented
21295 below. Among its distinguishing features are TigerVNC integration for
21296 easily remoting your desktop as well as support for the XDMCP protocol,
21297 which can be used by remote clients to start a session from the login
21300 In its most basic form, it can be used simply as:
21303 (service lightdm-service-type)
21306 A more elaborate example making use of the VNC capabilities and enabling
21307 more features and verbose logs could look like:
21310 (service lightdm-service-type
21311 (lightdm-configuration
21312 (allow-empty-passwords? #t)
21315 (vnc-server-command
21316 (file-append tigervnc-server "/bin/Xvnc"
21317 " -SecurityTypes None"))
21319 (list (lightdm-seat-configuration
21321 (user-session "ratpoison"))))))
21325 @c The LightDM service documentation can be auto-generated via the
21326 @c 'generate-doc' procedure at the bottom of the (gnu services lightdm)
21328 @c %start of fragment
21329 @deftp {Data Type} lightdm-configuration
21330 Available @code{lightdm-configuration} fields are:
21333 @item @code{lightdm} (default: @code{lightdm}) (type: file-like)
21334 The lightdm package to use.
21336 @item @code{allow-empty-passwords?} (default: @code{#f}) (type: boolean)
21337 Whether users not having a password set can login.
21339 @item @code{debug?} (default: @code{#f}) (type: boolean)
21340 Enable verbose output.
21342 @item @code{xorg-configuration} (type: xorg-configuration)
21343 The default Xorg server configuration to use to generate the Xorg server
21344 start script. It can be refined per seat via the @code{xserver-command}
21345 of the @code{<lightdm-seat-configuration>} record, if desired.
21347 @item @code{greeters} (type: list-of-greeter-configurations)
21348 The LightDM greeter configurations specifying the greeters to use.
21350 @item @code{seats} (type: list-of-seat-configurations)
21351 The seat configurations to use. A LightDM seat is akin to a user.
21353 @item @code{xdmcp?} (default: @code{#f}) (type: boolean)
21354 Whether a XDMCP server should listen on port UDP 177.
21356 @item @code{xdmcp-listen-address} (type: maybe-string)
21357 The host or IP address the XDMCP server listens for incoming
21358 connections. When unspecified, listen on for any hosts/IP addresses.
21360 @item @code{vnc-server?} (default: @code{#f}) (type: boolean)
21361 Whether a VNC server is started.
21363 @item @code{vnc-server-command} (type: file-like)
21364 The Xvnc command to use for the VNC server, it's possible to provide
21365 extra options not otherwise exposed along the command, for example to
21369 (vnc-server-command (file-append tigervnc-server "/bin/Xvnc"
21370 " -SecurityTypes None" ))
21373 Or to set a PasswordFile for the classic (unsecure) VncAuth
21377 (vnc-server-command (file-append tigervnc-server "/bin/Xvnc"
21378 " -PasswordFile /var/lib/lightdm/.vnc/passwd"))
21381 The password file should be manually created using the
21382 @command{vncpasswd} command. Note that LightDM will create new sessions
21383 for VNC users, which means they need to authenticate in the same way as
21386 @item @code{vnc-server-listen-address} (type: maybe-string)
21387 The host or IP address the VNC server listens for incoming connections.
21388 When unspecified, listen for any hosts/IP addresses.
21390 @item @code{vnc-server-port} (default: @code{5900}) (type: number)
21391 The TCP port the VNC server should listen to.
21393 @item @code{extra-config} (default: @code{()}) (type: list-of-strings)
21394 Extra configuration values to append to the LightDM configuration file.
21400 @c %end of fragment
21401 @c %start of fragment
21403 @deftp {Data Type} lightdm-gtk-greeter-configuration
21404 Available @code{lightdm-gtk-greeter-configuration} fields are:
21407 @item @code{lightdm-gtk-greeter} (default: @code{lightdm-gtk-greeter}) (type: file-like)
21408 The lightdm-gtk-greeter package to use.
21410 @item @code{assets} @
21411 (default: @code{(adwaita-icon-theme gnome-themes-extrahicolor-icon-theme)}) @
21412 (type: list-of-file-likes)
21413 The list of packages complementing the greeter, such as package
21414 providing icon themes.
21416 @item @code{theme-name} (default: @code{"Adwaita"}) (type: string)
21417 The name of the theme to use.
21419 @item @code{icon-theme-name} (default: @code{"Adwaita"}) (type: string)
21420 The name of the icon theme to use.
21422 @item @code{cursor-theme-name} (default: @code{"Adwaita"}) (type: string)
21423 The name of the cursor theme to use.
21425 @item @code{cursor-theme-size} (default: @code{16}) (type: number)
21426 The size to use for the the cursor theme.
21428 @item @code{allow-debugging?} (type: maybe-boolean)
21429 Set to #t to enable debug log level.
21431 @item @code{background} (type: file-like)
21432 The background image to use.
21434 @item @code{at-spi-enabled?} (default: @code{#f}) (type: boolean)
21435 Enable accessibility support through the Assistive Technology Service
21436 Provider Interface (AT-SPI).
21438 @item @code{a11y-states} @
21439 (default: @code{(contrast font keyboard reader)}) (type: list-of-a11y-states)
21440 The accessibility features to enable, given as list of symbols.
21442 @item @code{reader} (type: maybe-file-like)
21443 The command to use to launch a screen reader.
21445 @item @code{extra-config} (default: @code{()}) (type: list-of-strings)
21446 Extra configuration values to append to the LightDM GTK Greeter
21447 configuration file.
21452 @c %end of fragment
21453 @c %start of fragment
21455 @deftp {Data Type} lightdm-seat-configuration
21456 Available @code{lightdm-seat-configuration} fields are:
21459 @item @code{name} (type: seat-name)
21460 The name of the seat. An asterisk (*) can be used in the name to apply
21461 the seat configuration to all the seat names it matches.
21463 @item @code{user-session} (type: maybe-string)
21464 The session to use by default. The session name must be provided as a
21465 lowercase string, such as @code{"gnome"}, @code{"ratpoison"}, etc.
21467 @item @code{type} (default: @code{local}) (type: seat-type)
21468 The type of the seat, either the @code{local} or @code{xremote} symbol.
21470 @item @code{autologin-user} (type: maybe-string)
21471 The username to automatically log in with by default.
21473 @item @code{greeter-session} @
21474 (default: @code{lightdm-gtk-greeter}) (type: greeter-session)
21475 The greeter session to use, specified as a symbol. Currently, only
21476 @code{lightdm-gtk-greeter} is supported.
21478 @item @code{xserver-command} (type: maybe-file-like)
21479 The Xorg server command to run.
21481 @item @code{session-wrapper} (type: file-like)
21482 The xinitrc session wrapper to use.
21484 @item @code{extra-config} (default: @code{()}) (type: list-of-strings)
21485 Extra configuration values to append to the seat configuration section.
21489 @c %end of fragment
21492 @cindex Xorg, configuration
21493 @deftp {Data Type} xorg-configuration
21494 This data type represents the configuration of the Xorg graphical display
21495 server. Note that there is no Xorg service; instead, the X server is started
21496 by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
21497 of these display managers aggregates an @code{xorg-configuration} record.
21500 @item @code{modules} (default: @code{%default-xorg-modules})
21501 This is a list of @dfn{module packages} loaded by the Xorg
21502 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
21504 @item @code{fonts} (default: @code{%default-xorg-fonts})
21505 This is a list of font directories to add to the server's @dfn{font path}.
21507 @item @code{drivers} (default: @code{'()})
21508 This must be either the empty list, in which case Xorg chooses a graphics
21509 driver automatically, or a list of driver names that will be tried in this
21510 order---e.g., @code{("modesetting" "vesa")}.
21512 @item @code{resolutions} (default: @code{'()})
21513 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
21514 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
21517 @cindex keyboard layout, for Xorg
21518 @cindex keymap, for Xorg
21519 @item @code{keyboard-layout} (default: @code{#f})
21520 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
21521 English (``qwerty'') for a 105-key PC keyboard.
21523 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
21524 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
21525 information on how to specify the keyboard layout.
21527 @item @code{extra-config} (default: @code{'()})
21528 This is a list of strings or objects appended to the configuration file. It
21529 is used to pass extra text to be added verbatim to the configuration file.
21531 @item @code{server} (default: @code{xorg-server})
21532 This is the package providing the Xorg server.
21534 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
21535 This is the list of command-line arguments to pass to the X server. The
21536 default is @code{-nolisten tcp}.
21540 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
21541 [@var{login-manager-service-type}]
21542 Tell the log-in manager (of type @var{login-manager-service-type}) to use
21543 @var{config}, an @code{<xorg-configuration>} record.
21545 Since the Xorg configuration is embedded in the log-in manager's
21546 configuration---e.g., @code{gdm-configuration}---this procedure provides a
21547 shorthand to set the Xorg configuration.
21550 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
21551 Return a @code{startx} script in which the modules, fonts, etc. specified
21552 in @var{config}, are available. The result should be used in place of
21555 Usually the X server is started by a login manager.
21559 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
21560 Add @var{package}, a package for a screen locker or screen saver whose
21561 command is @var{program}, to the set of setuid programs and add a PAM entry
21562 for it. For example:
21565 (screen-locker-service xlockmore "xlock")
21568 makes the good ol' XlockMore usable.
21572 @node Printing Services
21573 @subsection Printing Services
21575 @cindex printer support with CUPS
21576 The @code{(gnu services cups)} module provides a Guix service definition
21577 for the CUPS printing service. To add printer support to a Guix
21578 system, add a @code{cups-service} to the operating system definition:
21580 @deffn {Scheme Variable} cups-service-type
21581 The service type for the CUPS print server. Its value should be a valid
21582 CUPS configuration (see below). To use the default settings, simply
21585 (service cups-service-type)
21589 The CUPS configuration controls the basic things about your CUPS
21590 installation: what interfaces it listens on, what to do if a print job
21591 fails, how much logging to do, and so on. To actually add a printer,
21592 you have to visit the @url{http://localhost:631} URL, or use a tool such
21593 as GNOME's printer configuration services. By default, configuring a
21594 CUPS service will generate a self-signed certificate if needed, for
21595 secure connections to the print server.
21597 Suppose you want to enable the Web interface of CUPS and also add
21598 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
21599 package and for HP printers @i{via} the @code{hplip-minimal} package.
21600 You can do that directly, like this (you need to use the
21601 @code{(gnu packages cups)} module):
21604 (service cups-service-type
21605 (cups-configuration
21606 (web-interface? #t)
21608 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
21612 If you wish to use the Qt5 based GUI which comes with the hplip
21613 package then it is suggested that you install the @code{hplip} package,
21614 either in your OS configuration file or as your user.
21617 The available configuration parameters follow. Each parameter
21618 definition is preceded by its type; for example, @samp{string-list foo}
21619 indicates that the @code{foo} parameter should be specified as a list of
21620 strings. There is also a way to specify the configuration as a string,
21621 if you have an old @code{cupsd.conf} file that you want to port over
21622 from some other system; see the end for more details.
21624 @c The following documentation was initially generated by
21625 @c (generate-documentation) in (gnu services cups). Manually maintained
21626 @c documentation is better, so we shouldn't hesitate to edit below as
21627 @c needed. However if the change you want to make to this documentation
21628 @c can be done in an automated way, it's probably easier to change
21629 @c (generate-documentation) than to make it below and have to deal with
21630 @c the churn as CUPS updates.
21633 Available @code{cups-configuration} fields are:
21635 @deftypevr {@code{cups-configuration} parameter} package cups
21639 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
21640 Drivers and other extensions to the CUPS package.
21643 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
21644 Configuration of where to write logs, what directories to use for print
21645 spools, and related privileged configuration parameters.
21647 Available @code{files-configuration} fields are:
21649 @deftypevr {@code{files-configuration} parameter} log-location access-log
21650 Defines the access log filename. Specifying a blank filename disables
21651 access log generation. The value @code{stderr} causes log entries to be
21652 sent to the standard error file when the scheduler is running in the
21653 foreground, or to the system log daemon when run in the background. The
21654 value @code{syslog} causes log entries to be sent to the system log
21655 daemon. The server name may be included in filenames using the string
21656 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
21658 Defaults to @samp{"/var/log/cups/access_log"}.
21661 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
21662 Where CUPS should cache data.
21664 Defaults to @samp{"/var/cache/cups"}.
21667 @deftypevr {@code{files-configuration} parameter} string config-file-perm
21668 Specifies the permissions for all configuration files that the scheduler
21671 Note that the permissions for the printers.conf file are currently
21672 masked to only allow access from the scheduler user (typically root).
21673 This is done because printer device URIs sometimes contain sensitive
21674 authentication information that should not be generally known on the
21675 system. There is no way to disable this security feature.
21677 Defaults to @samp{"0640"}.
21680 @deftypevr {@code{files-configuration} parameter} log-location error-log
21681 Defines the error log filename. Specifying a blank filename disables
21682 error log generation. The value @code{stderr} causes log entries to be
21683 sent to the standard error file when the scheduler is running in the
21684 foreground, or to the system log daemon when run in the background. The
21685 value @code{syslog} causes log entries to be sent to the system log
21686 daemon. The server name may be included in filenames using the string
21687 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
21689 Defaults to @samp{"/var/log/cups/error_log"}.
21692 @deftypevr {@code{files-configuration} parameter} string fatal-errors
21693 Specifies which errors are fatal, causing the scheduler to exit. The
21698 No errors are fatal.
21701 All of the errors below are fatal.
21704 Browsing initialization errors are fatal, for example failed connections
21705 to the DNS-SD daemon.
21708 Configuration file syntax errors are fatal.
21711 Listen or Port errors are fatal, except for IPv6 failures on the
21712 loopback or @code{any} addresses.
21715 Log file creation or write errors are fatal.
21718 Bad startup file permissions are fatal, for example shared TLS
21719 certificate and key files with world-read permissions.
21722 Defaults to @samp{"all -browse"}.
21725 @deftypevr {@code{files-configuration} parameter} boolean file-device?
21726 Specifies whether the file pseudo-device can be used for new printer
21727 queues. The URI @uref{file:///dev/null} is always allowed.
21729 Defaults to @samp{#f}.
21732 @deftypevr {@code{files-configuration} parameter} string group
21733 Specifies the group name or ID that will be used when executing external
21736 Defaults to @samp{"lp"}.
21739 @deftypevr {@code{files-configuration} parameter} string log-file-group
21740 Specifies the group name or ID that will be used for log files.
21742 Defaults to @samp{"lpadmin"}.
21745 @deftypevr {@code{files-configuration} parameter} string log-file-perm
21746 Specifies the permissions for all log files that the scheduler writes.
21748 Defaults to @samp{"0644"}.
21751 @deftypevr {@code{files-configuration} parameter} log-location page-log
21752 Defines the page log filename. Specifying a blank filename disables
21753 page log generation. The value @code{stderr} causes log entries to be
21754 sent to the standard error file when the scheduler is running in the
21755 foreground, or to the system log daemon when run in the background. The
21756 value @code{syslog} causes log entries to be sent to the system log
21757 daemon. The server name may be included in filenames using the string
21758 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
21760 Defaults to @samp{"/var/log/cups/page_log"}.
21763 @deftypevr {@code{files-configuration} parameter} string remote-root
21764 Specifies the username that is associated with unauthenticated accesses
21765 by clients claiming to be the root user. The default is @code{remroot}.
21767 Defaults to @samp{"remroot"}.
21770 @deftypevr {@code{files-configuration} parameter} file-name request-root
21771 Specifies the directory that contains print jobs and other HTTP request
21774 Defaults to @samp{"/var/spool/cups"}.
21777 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
21778 Specifies the level of security sandboxing that is applied to print
21779 filters, backends, and other child processes of the scheduler; either
21780 @code{relaxed} or @code{strict}. This directive is currently only
21781 used/supported on macOS.
21783 Defaults to @samp{strict}.
21786 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
21787 Specifies the location of TLS certificates and private keys. CUPS will
21788 look for public and private keys in this directory: @file{.crt} files
21789 for PEM-encoded certificates and corresponding @file{.key} files for
21790 PEM-encoded private keys.
21792 Defaults to @samp{"/etc/cups/ssl"}.
21795 @deftypevr {@code{files-configuration} parameter} file-name server-root
21796 Specifies the directory containing the server configuration files.
21798 Defaults to @samp{"/etc/cups"}.
21801 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
21802 Specifies whether the scheduler calls fsync(2) after writing
21803 configuration or state files.
21805 Defaults to @samp{#f}.
21808 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
21809 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
21812 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
21813 Specifies the directory where temporary files are stored.
21815 Defaults to @samp{"/var/spool/cups/tmp"}.
21818 @deftypevr {@code{files-configuration} parameter} string user
21819 Specifies the user name or ID that is used when running external
21822 Defaults to @samp{"lp"}.
21825 @deftypevr {@code{files-configuration} parameter} string set-env
21826 Set the specified environment variable to be passed to child processes.
21828 Defaults to @samp{"variable value"}.
21832 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
21833 Specifies the logging level for the AccessLog file. The @code{config}
21834 level logs when printers and classes are added, deleted, or modified and
21835 when configuration files are accessed or updated. The @code{actions}
21836 level logs when print jobs are submitted, held, released, modified, or
21837 canceled, and any of the conditions for @code{config}. The @code{all}
21838 level logs all requests.
21840 Defaults to @samp{actions}.
21843 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
21844 Specifies whether to purge job history data automatically when it is no
21845 longer required for quotas.
21847 Defaults to @samp{#f}.
21850 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
21851 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
21852 For example, @samp{"_cups" "_print"} will tell network clients that both
21853 CUPS sharing and IPP Everywhere are supported.
21855 Defaults to @samp{"_cups"}.
21858 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
21859 Specifies which protocols to use for local printer sharing.
21861 Defaults to @samp{dnssd}.
21864 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
21865 Specifies whether the CUPS web interface is advertised.
21867 Defaults to @samp{#f}.
21870 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
21871 Specifies whether shared printers are advertised.
21873 Defaults to @samp{#f}.
21876 @deftypevr {@code{cups-configuration} parameter} string classification
21877 Specifies the security classification of the server. Any valid banner
21878 name can be used, including @samp{"classified"}, @samp{"confidential"},
21879 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
21880 banner can be omitted to disable secure printing functions.
21882 Defaults to @samp{""}.
21885 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
21886 Specifies whether users may override the classification (cover page) of
21887 individual print jobs using the @code{job-sheets} option.
21889 Defaults to @samp{#f}.
21892 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
21893 Specifies the default type of authentication to use.
21895 Defaults to @samp{Basic}.
21898 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
21899 Specifies whether encryption will be used for authenticated requests.
21901 Defaults to @samp{Required}.
21904 @deftypevr {@code{cups-configuration} parameter} string default-language
21905 Specifies the default language to use for text and web content.
21907 Defaults to @samp{"en"}.
21910 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
21911 Specifies the default paper size for new print queues. @samp{"Auto"}
21912 uses a locale-specific default, while @samp{"None"} specifies there is
21913 no default paper size. Specific size names are typically
21914 @samp{"Letter"} or @samp{"A4"}.
21916 Defaults to @samp{"Auto"}.
21919 @deftypevr {@code{cups-configuration} parameter} string default-policy
21920 Specifies the default access policy to use.
21922 Defaults to @samp{"default"}.
21925 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
21926 Specifies whether local printers are shared by default.
21928 Defaults to @samp{#t}.
21931 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
21932 Specifies the delay for updating of configuration and state files, in
21933 seconds. A value of 0 causes the update to happen as soon as possible,
21934 typically within a few milliseconds.
21936 Defaults to @samp{30}.
21939 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
21940 Specifies what to do when an error occurs. Possible values are
21941 @code{abort-job}, which will discard the failed print job;
21942 @code{retry-job}, which will retry the job at a later time;
21943 @code{retry-current-job}, which retries the failed job immediately; and
21944 @code{stop-printer}, which stops the printer.
21946 Defaults to @samp{stop-printer}.
21949 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
21950 Specifies the maximum cost of filters that are run concurrently, which
21951 can be used to minimize disk, memory, and CPU resource problems. A
21952 limit of 0 disables filter limiting. An average print to a
21953 non-PostScript printer needs a filter limit of about 200. A PostScript
21954 printer needs about half that (100). Setting the limit below these
21955 thresholds will effectively limit the scheduler to printing a single job
21958 Defaults to @samp{0}.
21961 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
21962 Specifies the scheduling priority of filters that are run to print a
21963 job. The nice value ranges from 0, the highest priority, to 19, the
21966 Defaults to @samp{0}.
21969 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
21970 Specifies whether to do reverse lookups on connecting clients. The
21971 @code{double} setting causes @code{cupsd} to verify that the hostname
21972 resolved from the address matches one of the addresses returned for that
21973 hostname. Double lookups also prevent clients with unregistered
21974 addresses from connecting to your server. Only set this option to
21975 @code{#t} or @code{double} if absolutely required.
21977 Defaults to @samp{#f}.
21980 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
21981 Specifies the number of seconds to wait before killing the filters and
21982 backend associated with a canceled or held job.
21984 Defaults to @samp{30}.
21987 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
21988 Specifies the interval between retries of jobs in seconds. This is
21989 typically used for fax queues but can also be used with normal print
21990 queues whose error policy is @code{retry-job} or
21991 @code{retry-current-job}.
21993 Defaults to @samp{30}.
21996 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
21997 Specifies the number of retries that are done for jobs. 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{5}.
22005 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
22006 Specifies whether to support HTTP keep-alive connections.
22008 Defaults to @samp{#t}.
22011 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
22012 Specifies the maximum size of print files, IPP requests, and HTML form
22013 data. A limit of 0 disables the limit check.
22015 Defaults to @samp{0}.
22018 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
22019 Listens on the specified interfaces for connections. Valid values are
22020 of the form @var{address}:@var{port}, where @var{address} is either an
22021 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
22022 indicate all addresses. Values can also be file names of local UNIX
22023 domain sockets. The Listen directive is similar to the Port directive
22024 but allows you to restrict access to specific interfaces or networks.
22027 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
22028 Specifies the number of pending connections that will be allowed. This
22029 normally only affects very busy servers that have reached the MaxClients
22030 limit, but can also be triggered by large numbers of simultaneous
22031 connections. When the limit is reached, the operating system will
22032 refuse additional connections until the scheduler can accept the pending
22035 Defaults to @samp{128}.
22038 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
22039 Specifies a set of additional access controls.
22041 Available @code{location-access-controls} fields are:
22043 @deftypevr {@code{location-access-controls} parameter} file-name path
22044 Specifies the URI path to which the access control applies.
22047 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
22048 Access controls for all access to this path, in the same format as the
22049 @code{access-controls} of @code{operation-access-control}.
22051 Defaults to @samp{()}.
22054 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
22055 Access controls for method-specific access to this path.
22057 Defaults to @samp{()}.
22059 Available @code{method-access-controls} fields are:
22061 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
22062 If @code{#t}, apply access controls to all methods except the listed
22063 methods. Otherwise apply to only the listed methods.
22065 Defaults to @samp{#f}.
22068 @deftypevr {@code{method-access-controls} parameter} method-list methods
22069 Methods to which this access control applies.
22071 Defaults to @samp{()}.
22074 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
22075 Access control directives, as a list of strings. Each string should be
22076 one directive, such as @samp{"Order allow,deny"}.
22078 Defaults to @samp{()}.
22083 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
22084 Specifies the number of debugging messages that are retained for logging
22085 if an error occurs in a print job. Debug messages are logged regardless
22086 of the LogLevel setting.
22088 Defaults to @samp{100}.
22091 @deftypevr {@code{cups-configuration} parameter} log-level log-level
22092 Specifies the level of logging for the ErrorLog file. The value
22093 @code{none} stops all logging while @code{debug2} logs everything.
22095 Defaults to @samp{info}.
22098 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
22099 Specifies the format of the date and time in the log files. The value
22100 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
22102 Defaults to @samp{standard}.
22105 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
22106 Specifies the maximum number of simultaneous clients that are allowed by
22109 Defaults to @samp{100}.
22112 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
22113 Specifies the maximum number of simultaneous clients that are allowed
22114 from a single address.
22116 Defaults to @samp{100}.
22119 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
22120 Specifies the maximum number of copies that a user can print of each
22123 Defaults to @samp{9999}.
22126 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
22127 Specifies the maximum time a job may remain in the @code{indefinite}
22128 hold state before it is canceled. A value of 0 disables cancellation of
22131 Defaults to @samp{0}.
22134 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
22135 Specifies the maximum number of simultaneous jobs that are allowed. Set
22136 to 0 to allow an unlimited number of jobs.
22138 Defaults to @samp{500}.
22141 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
22142 Specifies the maximum number of simultaneous jobs that are allowed per
22143 printer. A value of 0 allows up to MaxJobs jobs per printer.
22145 Defaults to @samp{0}.
22148 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
22149 Specifies the maximum number of simultaneous jobs that are allowed per
22150 user. A value of 0 allows up to MaxJobs jobs per user.
22152 Defaults to @samp{0}.
22155 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
22156 Specifies the maximum time a job may take to print before it is
22157 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
22159 Defaults to @samp{10800}.
22162 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
22163 Specifies the maximum size of the log files before they are rotated, in
22164 bytes. The value 0 disables log rotation.
22166 Defaults to @samp{1048576}.
22169 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
22170 Specifies the maximum amount of time to allow between files in a
22171 multiple file print job, in seconds.
22173 Defaults to @samp{900}.
22176 @deftypevr {@code{cups-configuration} parameter} string page-log-format
22177 Specifies the format of PageLog lines. Sequences beginning with percent
22178 (@samp{%}) characters are replaced with the corresponding information,
22179 while all other characters are copied literally. The following percent
22180 sequences are recognized:
22184 insert a single percent character
22187 insert the value of the specified IPP attribute
22190 insert the number of copies for the current page
22193 insert the current page number
22196 insert the current date and time in common log format
22202 insert the printer name
22205 insert the username
22208 A value of the empty string disables page logging. The string @code{%p
22209 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
22210 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
22213 Defaults to @samp{""}.
22216 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
22217 Passes the specified environment variable(s) to child processes; a list
22220 Defaults to @samp{()}.
22223 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
22224 Specifies named access control policies.
22226 Available @code{policy-configuration} fields are:
22228 @deftypevr {@code{policy-configuration} parameter} string name
22229 Name of the policy.
22232 @deftypevr {@code{policy-configuration} parameter} string job-private-access
22233 Specifies an access list for a job's private values. @code{@@ACL} maps
22234 to the printer's requesting-user-name-allowed or
22235 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
22236 owner. @code{@@SYSTEM} maps to the groups listed for the
22237 @code{system-group} field of the @code{files-configuration},
22238 which is reified into the @code{cups-files.conf(5)} file. Other
22239 possible elements of the access list include specific user names, and
22240 @code{@@@var{group}} to indicate members of a specific group. The
22241 access list may also be simply @code{all} or @code{default}.
22243 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22246 @deftypevr {@code{policy-configuration} parameter} string job-private-values
22247 Specifies the list of job values to make private, or @code{all},
22248 @code{default}, or @code{none}.
22250 Defaults to @samp{"job-name job-originating-host-name
22251 job-originating-user-name phone"}.
22254 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
22255 Specifies an access list for a subscription's private values.
22256 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
22257 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
22258 owner. @code{@@SYSTEM} maps to the groups listed for the
22259 @code{system-group} field of the @code{files-configuration},
22260 which is reified into the @code{cups-files.conf(5)} file. Other
22261 possible elements of the access list include specific user names, and
22262 @code{@@@var{group}} to indicate members of a specific group. The
22263 access list may also be simply @code{all} or @code{default}.
22265 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22268 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
22269 Specifies the list of job values to make private, or @code{all},
22270 @code{default}, or @code{none}.
22272 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
22273 notify-subscriber-user-name notify-user-data"}.
22276 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
22277 Access control by IPP operation.
22279 Defaults to @samp{()}.
22283 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
22284 Specifies whether job files (documents) are preserved after a job is
22285 printed. If a numeric value is specified, job files are preserved for
22286 the indicated number of seconds after printing. Otherwise a boolean
22287 value applies indefinitely.
22289 Defaults to @samp{86400}.
22292 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
22293 Specifies whether the job history is preserved after a job is printed.
22294 If a numeric value is specified, the job history is preserved for the
22295 indicated number of seconds after printing. If @code{#t}, the job
22296 history is preserved until the MaxJobs limit is reached.
22298 Defaults to @samp{#t}.
22301 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
22302 Specifies the amount of time to wait for job completion before
22303 restarting the scheduler.
22305 Defaults to @samp{30}.
22308 @deftypevr {@code{cups-configuration} parameter} string rip-cache
22309 Specifies the maximum amount of memory to use when converting documents
22310 into bitmaps for a printer.
22312 Defaults to @samp{"128m"}.
22315 @deftypevr {@code{cups-configuration} parameter} string server-admin
22316 Specifies the email address of the server administrator.
22318 Defaults to @samp{"root@@localhost.localdomain"}.
22321 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
22322 The ServerAlias directive is used for HTTP Host header validation when
22323 clients connect to the scheduler from external interfaces. Using the
22324 special name @code{*} can expose your system to known browser-based DNS
22325 rebinding attacks, even when accessing sites through a firewall. If the
22326 auto-discovery of alternate names does not work, we recommend listing
22327 each alternate name with a ServerAlias directive instead of using
22330 Defaults to @samp{*}.
22333 @deftypevr {@code{cups-configuration} parameter} string server-name
22334 Specifies the fully-qualified host name of the server.
22336 Defaults to @samp{"localhost"}.
22339 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
22340 Specifies what information is included in the Server header of HTTP
22341 responses. @code{None} disables the Server header. @code{ProductOnly}
22342 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
22343 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
22344 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
22345 the output of the @code{uname} command. @code{Full} reports @code{CUPS
22346 2.0.0 (@var{uname}) IPP/2.0}.
22348 Defaults to @samp{Minimal}.
22351 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
22352 Listens on the specified interfaces for encrypted connections. Valid
22353 values are of the form @var{address}:@var{port}, where @var{address} is
22354 either an IPv6 address enclosed in brackets, an IPv4 address, or
22355 @code{*} to indicate all addresses.
22357 Defaults to @samp{()}.
22360 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
22361 Sets encryption options. By default, CUPS only supports encryption
22362 using TLS v1.0 or higher using known secure cipher suites. Security is
22363 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
22364 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
22365 suites, which are required for some older clients. The @code{AllowSSL3} option
22366 enables SSL v3.0, which is required for some older clients that do not support
22367 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
22368 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
22369 protocol version to TLS v1.1.
22371 Defaults to @samp{()}.
22374 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
22375 Specifies whether the scheduler requires clients to strictly adhere to
22376 the IPP specifications.
22378 Defaults to @samp{#f}.
22381 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
22382 Specifies the HTTP request timeout, in seconds.
22384 Defaults to @samp{900}.
22388 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
22389 Specifies whether the web interface is enabled.
22391 Defaults to @samp{#f}.
22394 At this point you're probably thinking ``oh dear, Guix manual, I like
22395 you but you can stop already with the configuration options''. Indeed.
22396 However, one more point: it could be that you have an existing
22397 @code{cupsd.conf} that you want to use. In that case, you can pass an
22398 @code{opaque-cups-configuration} as the configuration of a
22399 @code{cups-service-type}.
22401 Available @code{opaque-cups-configuration} fields are:
22403 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
22407 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
22408 The contents of the @code{cupsd.conf}, as a string.
22411 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
22412 The contents of the @code{cups-files.conf} file, as a string.
22415 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
22416 strings of the same name, you could instantiate a CUPS service like
22420 (service cups-service-type
22421 (opaque-cups-configuration
22422 (cupsd.conf cupsd.conf)
22423 (cups-files.conf cups-files.conf)))
22427 @node Desktop Services
22428 @subsection Desktop Services
22430 The @code{(gnu services desktop)} module provides services that are
22431 usually useful in the context of a ``desktop'' setup---that is, on a
22432 machine running a graphical display server, possibly with graphical user
22433 interfaces, etc. It also defines services that provide specific desktop
22434 environments like GNOME, Xfce or MATE.
22436 To simplify things, the module defines a variable containing the set of
22437 services that users typically expect on a machine with a graphical
22438 environment and networking:
22440 @defvr {Scheme Variable} %desktop-services
22441 This is a list of services that builds upon @code{%base-services} and
22442 adds or adjusts services for a typical ``desktop'' setup.
22444 In particular, it adds a graphical login manager (@pxref{X Window,
22445 @code{gdm-service-type}}), screen lockers, a network management tool
22446 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
22447 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
22448 energy and color management services, the @code{elogind} login and seat
22449 manager, the Polkit privilege service, the GeoClue location service, the
22450 AccountsService daemon that allows authorized users change system passwords,
22451 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
22452 name service switch service configured to be able to use @code{nss-mdns}
22453 (@pxref{Name Service Switch, mDNS}).
22456 The @code{%desktop-services} variable can be used as the @code{services}
22457 field of an @code{operating-system} declaration (@pxref{operating-system
22458 Reference, @code{services}}).
22460 Additionally, the @code{gnome-desktop-service-type},
22461 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
22462 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
22463 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
22464 ``add GNOME'' means that system-level services like the backlight adjustment
22465 helpers and the power management utilities are added to the system, extending
22466 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
22467 elevated privileges on a limited number of special-purpose system interfaces.
22468 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
22469 the GNOME metapackage to the system profile. Likewise, adding the Xfce
22470 service not only adds the @code{xfce} metapackage to the system profile, but
22471 it also gives the Thunar file manager the ability to open a ``root-mode'' file
22472 management window, if the user authenticates using the administrator's
22473 password via the standard polkit graphical interface. To ``add MATE'' means
22474 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
22475 to operate with elevated privileges on a limited number of special-purpose
22476 system interfaces. Additionally, adding a service of type
22477 @code{mate-desktop-service-type} adds the MATE metapackage to the system
22478 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
22479 appropriately, and several of Enlightenment's binaries are set as setuid,
22480 allowing Enlightenment's screen locker and other functionality to work as
22483 The desktop environments in Guix use the Xorg display server by
22484 default. If you'd like to use the newer display server protocol
22485 called Wayland, you need to enable Wayland support in GDM
22486 (@pxref{wayland-gdm}). Another solution is to use the
22487 @code{sddm-service} instead of GDM as the graphical login manager.
22488 You should then select the ``GNOME (Wayland)'' session in SDDM@.
22489 Alternatively you can also try starting GNOME on Wayland manually from a
22490 TTY with the command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
22491 gnome-session``. Currently only GNOME has support for Wayland.
22493 @defvr {Scheme Variable} gnome-desktop-service-type
22494 This is the type of the service that adds the @uref{https://www.gnome.org,
22495 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
22496 object (see below).
22498 This service adds the @code{gnome} package to the system profile, and extends
22499 polkit with the actions from @code{gnome-settings-daemon}.
22502 @deftp {Data Type} gnome-desktop-configuration
22503 Configuration record for the GNOME desktop environment.
22506 @item @code{gnome} (default: @code{gnome})
22507 The GNOME package to use.
22511 @defvr {Scheme Variable} xfce-desktop-service-type
22512 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
22513 desktop environment. Its value is an @code{xfce-desktop-configuration} object
22516 This service adds the @code{xfce} package to the system profile, and
22517 extends polkit with the ability for @code{thunar} to manipulate the file
22518 system as root from within a user session, after the user has authenticated
22519 with the administrator's password.
22521 Note that @code{xfce4-panel} and its plugin packages should be installed in
22522 the same profile to ensure compatibility. When using this service, you should
22523 add extra plugins (@code{xfce4-whiskermenu-plugin},
22524 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
22525 @code{operating-system}.
22528 @deftp {Data Type} xfce-desktop-configuration
22529 Configuration record for the Xfce desktop environment.
22532 @item @code{xfce} (default: @code{xfce})
22533 The Xfce package to use.
22537 @deffn {Scheme Variable} mate-desktop-service-type
22538 This is the type of the service that runs the @uref{https://mate-desktop.org/,
22539 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
22540 object (see below).
22542 This service adds the @code{mate} package to the system
22543 profile, and extends polkit with the actions from
22544 @code{mate-settings-daemon}.
22547 @deftp {Data Type} mate-desktop-configuration
22548 Configuration record for the MATE desktop environment.
22551 @item @code{mate} (default: @code{mate})
22552 The MATE package to use.
22556 @deffn {Scheme Variable} lxqt-desktop-service-type
22557 This is the type of the service that runs the @uref{https://lxqt-project.org,
22558 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
22559 object (see below).
22561 This service adds the @code{lxqt} package to the system
22565 @deftp {Data Type} lxqt-desktop-configuration
22566 Configuration record for the LXQt desktop environment.
22569 @item @code{lxqt} (default: @code{lxqt})
22570 The LXQT package to use.
22574 @deffn {Scheme Variable} enlightenment-desktop-service-type
22575 Return a service that adds the @code{enlightenment} package to the system
22576 profile, and extends dbus with actions from @code{efl}.
22579 @deftp {Data Type} enlightenment-desktop-service-configuration
22581 @item @code{enlightenment} (default: @code{enlightenment})
22582 The enlightenment package to use.
22586 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
22587 the default @code{%desktop-services} variable doesn't include any of
22588 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
22589 @code{%desktop-services} in the @code{services} field of your
22590 @code{operating-system}:
22593 (use-modules (gnu))
22594 (use-service-modules desktop)
22597 ;; cons* adds items to the list given as its last argument.
22598 (services (cons* (service gnome-desktop-service-type)
22599 (service xfce-desktop-service)
22600 %desktop-services))
22604 These desktop environments will then be available as options in the
22605 graphical login window.
22607 The actual service definitions included in @code{%desktop-services} and
22608 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
22609 are described below.
22611 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()] @
22613 Return a service that runs the ``system bus'', using @var{dbus}, with
22614 support for @var{services}. When @var{verbose?} is true, it causes the
22615 @samp{DBUS_VERBOSE} environment variable to be set to @samp{1}; a
22616 verbose-enabled D-Bus package such as @code{dbus-verbose} should be
22617 provided as @var{dbus} in this scenario. The verbose output is logged
22618 to @file{/var/log/dbus-daemon.log}.
22620 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
22621 facility. Its system bus is used to allow system services to communicate
22622 and to be notified of system-wide events.
22624 @var{services} must be a list of packages that provide an
22625 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
22626 and policy files. For example, to allow avahi-daemon to use the system bus,
22627 @var{services} must be equal to @code{(list avahi)}.
22630 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
22631 Return a service that runs the @code{elogind} login and
22632 seat management daemon. @uref{https://github.com/elogind/elogind,
22633 Elogind} exposes a D-Bus interface that can be used to know which users
22634 are logged in, know what kind of sessions they have open, suspend the
22635 system, inhibit system suspend, reboot the system, and other tasks.
22637 Elogind handles most system-level power events for a computer, for
22638 example suspending the system when a lid is closed, or shutting it down
22639 when the power button is pressed.
22641 The @var{config} keyword argument specifies the configuration for
22642 elogind, and should be the result of an @code{(elogind-configuration
22643 (@var{parameter} @var{value})...)} invocation. Available parameters and
22644 their default values are:
22647 @item kill-user-processes?
22649 @item kill-only-users
22651 @item kill-exclude-users
22653 @item inhibit-delay-max-seconds
22655 @item handle-power-key
22657 @item handle-suspend-key
22659 @item handle-hibernate-key
22661 @item handle-lid-switch
22663 @item handle-lid-switch-docked
22665 @item handle-lid-switch-external-power
22666 @code{*unspecified*}
22667 @item power-key-ignore-inhibited?
22669 @item suspend-key-ignore-inhibited?
22671 @item hibernate-key-ignore-inhibited?
22673 @item lid-switch-ignore-inhibited?
22675 @item holdoff-timeout-seconds
22679 @item idle-action-seconds
22681 @item runtime-directory-size-percent
22683 @item runtime-directory-size
22687 @item suspend-state
22688 @code{("mem" "standby" "freeze")}
22691 @item hibernate-state
22693 @item hibernate-mode
22694 @code{("platform" "shutdown")}
22695 @item hybrid-sleep-state
22697 @item hybrid-sleep-mode
22698 @code{("suspend" "platform" "shutdown")}
22702 @deffn {Scheme Procedure} accountsservice-service @
22703 [#:accountsservice @var{accountsservice}]
22704 Return a service that runs AccountsService, a system service that can
22705 list available accounts, change their passwords, and so on.
22706 AccountsService integrates with PolicyKit to enable unprivileged users
22707 to acquire the capability to modify their system configuration.
22708 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
22709 accountsservice web site} for more information.
22711 The @var{accountsservice} keyword argument is the @code{accountsservice}
22712 package to expose as a service.
22715 @deffn {Scheme Procedure} polkit-service @
22716 [#:polkit @var{polkit}]
22717 Return a service that runs the
22718 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
22719 management service}, which allows system administrators to grant access to
22720 privileged operations in a structured way. By querying the Polkit service, a
22721 privileged system component can know when it should grant additional
22722 capabilities to ordinary users. For example, an ordinary user can be granted
22723 the capability to suspend the system if the user is logged in locally.
22726 @defvr {Scheme Variable} polkit-wheel-service
22727 Service that adds the @code{wheel} group as admins to the Polkit
22728 service. This makes it so that users in the @code{wheel} group are queried
22729 for their own passwords when performing administrative actions instead of
22730 @code{root}'s, similar to the behaviour used by @code{sudo}.
22733 @defvr {Scheme Variable} upower-service-type
22734 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
22735 system-wide monitor for power consumption and battery levels, with the given
22736 configuration settings.
22738 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
22739 notably used by GNOME.
22742 @deftp {Data Type} upower-configuration
22743 Data type representation the configuration for UPower.
22747 @item @code{upower} (default: @var{upower})
22748 Package to use for @code{upower}.
22750 @item @code{watts-up-pro?} (default: @code{#f})
22751 Enable the Watts Up Pro device.
22753 @item @code{poll-batteries?} (default: @code{#t})
22754 Enable polling the kernel for battery level changes.
22756 @item @code{ignore-lid?} (default: @code{#f})
22757 Ignore the lid state, this can be useful if it's incorrect on a device.
22759 @item @code{use-percentage-for-policy?} (default: @code{#t})
22760 Whether a to use a policy based on battery percentage rather than on
22761 estimated time left. A policy based on battery percentage is usually
22764 @item @code{percentage-low} (default: @code{20})
22765 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22766 at which the battery is considered low.
22768 @item @code{percentage-critical} (default: @code{5})
22769 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22770 at which the battery is considered critical.
22772 @item @code{percentage-action} (default: @code{2})
22773 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22774 at which action will be taken.
22776 @item @code{time-low} (default: @code{1200})
22777 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22778 seconds at which the battery is considered low.
22780 @item @code{time-critical} (default: @code{300})
22781 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22782 seconds at which the battery is considered critical.
22784 @item @code{time-action} (default: @code{120})
22785 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22786 seconds at which action will be taken.
22788 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
22789 The action taken when @code{percentage-action} or @code{time-action} is
22790 reached (depending on the configuration of @code{use-percentage-for-policy?}).
22792 Possible values are:
22802 @code{'hybrid-sleep}.
22808 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
22809 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
22810 UDisks}, a @dfn{disk management} daemon that provides user interfaces
22811 with notifications and ways to mount/unmount disks. Programs that talk
22812 to UDisks include the @command{udisksctl} command, part of UDisks, and
22813 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
22814 it will only be able to use the file-system utilities installed in the
22815 system profile. For example if you want to be able to mount NTFS
22816 file-systems in read and write fashion, you'll need to have
22817 @code{ntfs-3g} installed system-wide.
22820 @deffn {Scheme Variable} colord-service-type
22821 This is the type of the service that runs @command{colord}, a system
22822 service with a D-Bus
22823 interface to manage the color profiles of input and output devices such as
22824 screens and scanners. It is notably used by the GNOME Color Manager graphical
22825 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
22826 site} for more information.
22829 @cindex scanner access
22830 @defvr {Scheme Variable} sane-service-type
22831 This service provides access to scanners @i{via}
22832 @uref{http://www.sane-project.org, SANE} by installing the necessary
22833 udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
22834 Services}) and relies by default on @code{sane-backends-minimal} package
22835 (see below) for hardware support.
22838 @defvr {Scheme Variable} sane-backends-minimal
22839 The default package which the @code{sane-service-type} installs. It
22840 supports many recent scanners.
22843 @defvr {Scheme Variable} sane-backends
22844 This package includes support for all scanners that
22845 @code{sane-backends-minimal} supports, plus older Hewlett-Packard
22846 scanners supported by @code{hplip} package. In order to use this on
22847 a system which relies on @code{%desktop-services}, you may use
22848 @code{modify-services} (@pxref{Service Reference,
22849 @code{modify-services}}) as illustrated below:
22852 (use-modules (gnu))
22853 (use-service-modules
22856 (use-package-modules
22860 (define %my-desktop-services
22861 ;; List of desktop services that supports a broader range of scanners.
22862 (modify-services %desktop-services
22863 (sane-service-type _ => sane-backends)))
22867 (services %my-desktop-services))
22871 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
22872 Return a configuration allowing an application to access GeoClue
22873 location data. @var{name} is the Desktop ID of the application, without
22874 the @code{.desktop} part. If @var{allowed?} is true, the application
22875 will have access to location information by default. The boolean
22876 @var{system?} value indicates whether an application is a system component
22877 or not. Finally @var{users} is a list of UIDs of all users for which
22878 this application is allowed location info access. An empty users list
22879 means that all users are allowed.
22882 @defvr {Scheme Variable} %standard-geoclue-applications
22883 The standard list of well-known GeoClue application configurations,
22884 granting authority to the GNOME date-and-time utility to ask for the
22885 current location in order to set the time zone, and allowing the
22886 IceCat and Epiphany web browsers to request location information.
22887 IceCat and Epiphany both query the user before allowing a web page to
22888 know the user's location.
22891 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
22892 [#:whitelist '()] @
22893 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
22894 [#:submit-data? #f]
22895 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
22896 [#:submission-nick "geoclue"] @
22897 [#:applications %standard-geoclue-applications]
22898 Return a service that runs the GeoClue location service. This service
22899 provides a D-Bus interface to allow applications to request access to a
22900 user's physical location, and optionally to add information to online
22901 location databases. See
22902 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
22903 web site} for more information.
22906 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
22907 [@w{#:auto-enable? #f}]
22908 Return a service that runs the @command{bluetoothd} daemon, which
22909 manages all the Bluetooth devices and provides a number of D-Bus
22910 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
22911 powered automatically at boot, which can be useful when using a
22912 bluetooth keyboard or mouse.
22914 Users need to be in the @code{lp} group to access the D-Bus service.
22917 @deffn {Scheme Variable} bluetooth-service-type
22918 This is the type for the @uref{https://bluez.org/, Linux Bluetooth Protocol
22919 Stack} (BlueZ) system, which generates the @file{/etc/bluetooth/main.conf}
22920 configuration file. The value for this type is a @command{bluetooth-configuration}
22921 record as in this example:
22924 (service bluetooth-service-type)
22927 See below for details about @code{bluetooth-configuration}.
22930 @deftp {Data Type} bluetooth-configuration
22931 Data type representing the configuration for @code{bluetooth-service}.
22934 @item @code{bluez} (default: @code{bluez})
22935 @code{bluez} package to use.
22937 @item @code{name} (default: @code{"BlueZ"})
22938 Default adapter name.
22940 @item @code{class} (default: @code{#x000000})
22941 Default device class. Only the major and minor device class bits are considered.
22943 @item @code{discoverable-timeout} (default: @code{180})
22944 How long to stay in discoverable mode before going back to non-discoverable. The
22945 value is in seconds.
22947 @item @code{always-pairable?} (default: @code{#f})
22948 Always allow pairing even if there are no agents registered.
22950 @item @code{pairable-timeout} (default: @code{0})
22951 How long to stay in pairable mode before going back to non-discoverable. The
22952 value is in seconds.
22954 @item @code{device-id} (default: @code{#f})
22955 Use vendor id source (assigner), vendor, product and version information for
22956 DID profile support. The values are separated by ":" and @var{assigner}, @var{VID},
22957 @var{PID} and @var{version}.
22959 Possible values are:
22963 @code{#f} to disable it,
22966 @code{"assigner:1234:5678:abcd"}, where @var{assigner} is either @code{usb} (default)
22967 or @code{bluetooth}.
22971 @item @code{reverse-service-discovery?} (default: @code{#t})
22972 Do reverse service discovery for previously unknown devices that connect to
22973 us. For BR/EDR this option is really only needed for qualification since the
22974 BITE tester doesn't like us doing reverse SDP for some test cases, for LE
22975 this disables the GATT client functionally so it can be used in system which
22976 can only operate as peripheral.
22978 @item @code{name-resolving?} (default: @code{#t})
22979 Enable name resolving after inquiry. Set it to @code{#f} if you don't need
22980 remote devices name and want shorter discovery cycle.
22982 @item @code{debug-keys?} (default: @code{#f})
22983 Enable runtime persistency of debug link keys. Default is false which makes
22984 debug link keys valid only for the duration of the connection that they were
22987 @item @code{controller-mode} (default: @code{'dual})
22988 Restricts all controllers to the specified transport. @code{'dual} means both
22989 BR/EDR and LE are enabled (if supported by the hardware).
22991 Possible values are:
23005 @item @code{multi-profile} (default: @code{'off})
23006 Enables Multi Profile Specification support. This allows to specify if system
23007 supports only Multiple Profiles Single Device (MPSD) configuration or both
23008 Multiple Profiles Single Device (MPSD) and Multiple Profiles Multiple Devices
23009 (MPMD) configurations.
23011 Possible values are:
23025 @item @code{fast-connectable?} (default: @code{#f})
23026 Permanently enables the Fast Connectable setting for adapters that support
23027 it. When enabled other devices can connect faster to us, however the
23028 tradeoff is increased power consumptions. This feature will fully work only
23029 on kernel version 4.1 and newer.
23031 @item @code{privacy} (default: @code{'off})
23032 Default privacy settings.
23036 @code{'off}: Disable local privacy
23039 @code{'network/on}: A device will only accept advertising packets from peer
23040 devices that contain private addresses. It may not be compatible with some
23041 legacy devices since it requires the use of RPA(s) all the time
23044 @code{'device}: A device in device privacy mode is only concerned about the
23045 privacy of the device and will accept advertising packets from peer devices
23046 that contain their Identity Address as well as ones that contain a private
23047 address, even if the peer device has distributed its IRK in the past
23051 and additionally, if @var{controller-mode} is set to @code{'dual}:
23055 @code{'limited-network}: Apply Limited Discoverable Mode to advertising, which
23056 follows the same policy as to BR/EDR that publishes the identity address when
23057 discoverable, and Network Privacy Mode for scanning
23060 @code{'limited-device}: Apply Limited Discoverable Mode to advertising, which
23061 follows the same policy as to BR/EDR that publishes the identity address when
23062 discoverable, and Device Privacy Mode for scanning.
23066 @item @code{just-works-repairing} (default: @code{'never})
23067 Specify the policy to the JUST-WORKS repairing initiated by peer.
23082 @item @code{temporary-timeout} (default: @code{30})
23083 How long to keep temporary devices around. The value is in seconds. @code{0}
23084 disables the timer completely.
23086 @item @code{refresh-discovery?} (default: @code{#t})
23087 Enables the device to issue an SDP request to update known services when
23088 profile is connected.
23090 @item @code{experimental} (default: @code{#f})
23091 Enables experimental features and interfaces, alternatively a list of UUIDs
23104 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
23107 List of possible UUIDs:
23110 @code{d4992530-b9ec-469f-ab01-6c481c47da1c}: BlueZ Experimental Debug,
23113 @code{671b10b5-42c0-4696-9227-eb28d1b049d6}: BlueZ Experimental Simultaneous Central and Peripheral,
23116 @code{"15c0a148-c273-11ea-b3de-0242ac130004}: BlueZ Experimental LL privacy,
23119 @code{330859bc-7506-492d-9370-9a6f0614037f}: BlueZ Experimental Bluetooth Quality Report,
23122 @code{a6695ace-ee7f-4fb9-881a-5fac66c629af}: BlueZ Experimental Offload Codecs.
23125 @item @code{remote-name-request-retry-delay} (default: @code{300})
23126 The duration to avoid retrying to resolve a peer's name, if the previous
23129 @item @code{page-scan-type} (default: @code{#f})
23130 BR/EDR Page scan activity type.
23132 @item @code{page-scan-interval} (default: @code{#f})
23133 BR/EDR Page scan activity interval.
23135 @item @code{page-scan-window} (default: @code{#f})
23136 BR/EDR Page scan activity window.
23138 @item @code{inquiry-scan-type} (default: @code{#f})
23139 BR/EDR Inquiry scan activity type.
23141 @item @code{inquiry-scan-interval} (default: @code{#f})
23142 BR/EDR Inquiry scan activity interval.
23144 @item @code{inquiry-scan-window} (default: @code{#f})
23145 BR/EDR Inquiry scan activity window.
23147 @item @code{link-supervision-timeout} (default: @code{#f})
23148 BR/EDR Link supervision timeout.
23150 @item @code{page-timeout} (default: @code{#f})
23151 BR/EDR Page timeout.
23153 @item @code{min-sniff-interval} (default: @code{#f})
23154 BR/EDR minimum sniff interval.
23156 @item @code{max-sniff-interval} (default: @code{#f})
23157 BR/EDR maximum sniff interval.
23159 @item @code{min-advertisement-interval} (default: @code{#f})
23160 LE minimum advertisement interval (used for legacy advertisement only).
23162 @item @code{max-advertisement-interval} (default: @code{#f})
23163 LE maximum advertisement interval (used for legacy advertisement only).
23165 @item @code{multi-advertisement-rotation-interval} (default: @code{#f})
23166 LE multiple advertisement rotation interval.
23168 @item @code{scan-interval-auto-connect} (default: @code{#f})
23169 LE scanning interval used for passive scanning supporting auto connect.
23171 @item @code{scan-window-auto-connect} (default: @code{#f})
23172 LE scanning window used for passive scanning supporting auto connect.
23174 @item @code{scan-interval-suspend} (default: @code{#f})
23175 LE scanning interval used for active scanning supporting wake from suspend.
23177 @item @code{scan-window-suspend} (default: @code{#f})
23178 LE scanning window used for active scanning supporting wake from suspend.
23180 @item @code{scan-interval-discovery} (default: @code{#f})
23181 LE scanning interval used for active scanning supporting discovery.
23183 @item @code{scan-window-discovery} (default: @code{#f})
23184 LE scanning window used for active scanning supporting discovery.
23186 @item @code{scan-interval-adv-monitor} (default: @code{#f})
23187 LE scanning interval used for passive scanning supporting the advertisement monitor APIs.
23189 @item @code{scan-window-adv-monitor} (default: @code{#f})
23190 LE scanning window used for passive scanning supporting the advertisement monitor APIs.
23192 @item @code{scan-interval-connect} (default: @code{#f})
23193 LE scanning interval used for connection establishment.
23195 @item @code{scan-window-connect} (default: @code{#f})
23196 LE scanning window used for connection establishment.
23198 @item @code{min-connection-interval} (default: @code{#f})
23199 LE default minimum connection interval. This value is superseded by any specific
23200 value provided via the Load Connection Parameters interface.
23202 @item @code{max-connection-interval} (default: @code{#f})
23203 LE default maximum connection interval. This value is superseded by any specific
23204 value provided via the Load Connection Parameters interface.
23206 @item @code{connection-latency} (default: @code{#f})
23207 LE default connection latency. This value is superseded by any specific
23208 value provided via the Load Connection Parameters interface.
23210 @item @code{connection-supervision-timeout} (default: @code{#f})
23211 LE default connection supervision timeout. This value is superseded by any specific
23212 value provided via the Load Connection Parameters interface.
23214 @item @code{autoconnect-timeout} (default: @code{#f})
23215 LE default autoconnect timeout. This value is superseded by any specific
23216 value provided via the Load Connection Parameters interface.
23218 @item @code{adv-mon-allowlist-scan-duration} (default: @code{300})
23219 Allowlist scan duration during interleaving scan. Only used when scanning for ADV
23220 monitors. The units are msec.
23222 @item @code{adv-mon-no-filter-scan-duration} (default: @code{500})
23223 No filter scan duration during interleaving scan. Only used when scanning for ADV
23224 monitors. The units are msec.
23226 @item @code{enable-adv-mon-interleave-scan?} (default: @code{#t})
23227 Enable/Disable Advertisement Monitor interleave scan for power saving.
23229 @item @code{cache} (default: @code{'always})
23230 GATT attribute cache.
23232 Possible values are:
23235 @code{'always}: Always cache attributes even for devices not paired, this is
23236 recommended as it is best for interoperability, with more consistent
23237 reconnection times and enables proper tracking of notifications for all
23241 @code{'yes}: Only cache attributes of paired devices
23244 @code{'no}: Never cache attributes.
23247 @item @code{key-size} (default: @code{0})
23248 Minimum required Encryption Key Size for accessing secured characteristics.
23250 Possible values are:
23253 @code{0}: Don't care
23256 @code{7 <= N <= 16}
23259 @item @code{exchange-mtu} (default: @code{517})
23260 Exchange MTU size. Possible values are:
23264 @code{23 <= N <= 517}
23267 @item @code{att-channels} (default: @code{3})
23268 Number of ATT channels. Possible values are:
23272 @code{1}: Disables EATT
23278 @item @code{session-mode} (default: @code{'basic})
23279 AVDTP L2CAP signalling channel mode.
23281 Possible values are:
23285 @code{'basic}: Use L2CAP basic mode
23288 @code{'ertm}: Use L2CAP enhanced retransmission mode.
23291 @item @code{stream-mode} (default: @code{'basic})
23292 AVDTP L2CAP transport channel mode.
23294 Possible values are:
23298 @code{'basic}: Use L2CAP basic mode
23301 @code{'streaming}: Use L2CAP streaming mode.
23304 @item @code{reconnect-uuids} (default: @code{'()})
23305 The ReconnectUUIDs defines the set of remote services that should try
23306 to be reconnected to in case of a link loss (link supervision
23307 timeout). The policy plugin should contain a sane set of values by
23308 default, but this list can be overridden here. By setting the list to
23309 empty the reconnection feature gets disabled.
23318 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
23321 @item @code{reconnect-attempts} (default: @code{7})
23322 Defines the number of attempts to reconnect after a link lost. Setting
23323 the value to 0 disables reconnecting feature.
23325 @item @code{reconnect-intervals} (default: @code{'(1 2 4 8 16 32 64)})
23326 Defines a list of intervals in seconds to use in between attempts. If
23327 the number of attempts defined in @var{reconnect-attempts} is bigger than
23328 the list of intervals the last interval is repeated until the last attempt.
23330 @item @code{auto-enable?} (default: @code{#f})
23331 Defines option to enable all controllers when they are found. This includes
23332 adapters present on start as well as adapters that are plugged in later on.
23334 @item @code{resume-delay} (default: @code{2})
23335 Audio devices that were disconnected due to suspend will be reconnected on
23336 resume. @var{resume-delay} determines the delay between when the controller
23337 resumes from suspend and a connection attempt is made. A longer delay is
23338 better for better co-existence with Wi-Fi. The value is in seconds.
23340 @item @code{rssi-sampling-period} (default: @code{#xFF})
23341 Default RSSI Sampling Period. This is used when a client registers an
23342 advertisement monitor and leaves the RSSISamplingPeriod unset.
23344 Possible values are:
23347 @code{#x0}: Report all advertisements
23350 @code{N = #xXX}: Report advertisements every N x 100 msec (range: #x01 to #xFE)
23353 @code{#xFF}: Report only one advertisement per device during monitoring period.
23359 @defvr {Scheme Variable} gnome-keyring-service-type
23360 This is the type of the service that adds the
23361 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
23362 value is a @code{gnome-keyring-configuration} object (see below).
23364 This service adds the @code{gnome-keyring} package to the system profile
23365 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
23366 a user's login keyring when they log in or setting its password with passwd.
23369 @deftp {Data Type} gnome-keyring-configuration
23370 Configuration record for the GNOME Keyring service.
23373 @item @code{keyring} (default: @code{gnome-keyring})
23374 The GNOME keyring package to use.
23376 @item @code{pam-services}
23377 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
23378 services to extend, where @var{service} is the name of an existing
23379 service to extend and @var{kind} is one of @code{login} or
23382 If @code{login} is given, it adds an optional
23383 @code{pam_gnome_keyring.so} to the auth block without arguments and to
23384 the session block with @code{auto_start}. If @code{passwd} is given, it
23385 adds an optional @code{pam_gnome_keyring.so} to the password block
23388 By default, this field contains ``gdm-password'' with the value @code{login}
23389 and ``passwd'' is with the value @code{passwd}.
23393 @defvr {Scheme Variable} seatd-service-type
23394 @uref{https://sr.ht/~kennylevinsen/seatd/, seatd} is a minimal seat
23397 Seat management takes care of mediating access to shared devices (graphics,
23398 input), without requiring the applications needing access to be root.
23403 ;; make sure seatd is running
23404 (service seatd-service-type))
23406 ;; normally one would want %base-services
23411 @code{seatd} operates over a UNIX domain socket, with @code{libseat}
23412 providing the client side of the protocol. Applications that acquire
23413 access to the shared resources via @code{seatd} (e.g. @code{sway})
23414 need to be able to talk to this socket.
23415 This can be achieved by adding the user they run under to the group
23416 owning @code{seatd}'s socket (usually ``seat''), like so:
23422 (supplementary-groups '("wheel" ; allow use of sudo, etc.
23423 "seat" ; seat management
23424 "audio" ; sound card
23425 "video" ; video devices such as webcams
23426 "cdrom")) ; the good ol' CD-ROM
23427 (comment "Bob's sister"))
23430 Depending on your setup, you will have to not only add regular users,
23431 but also system users to this group. For instance, some greetd greeters
23432 require graphics and therefore also need to negotiate with seatd.
23436 @deftp {Data Type} seatd-configuration
23437 Configuration record for the seatd daemon service.
23440 @item @code{seatd} (default: @code{seatd})
23441 The seatd package to use.
23443 @item @code{group} (default: @samp{"seat"})
23444 Group to own the seatd socket.
23446 @item @code{socket} (default: @samp{"/run/seatd.sock"})
23447 Where to create the seatd socket.
23449 @item @code{logfile} (default: @samp{"/var/log/seatd.log"})
23450 Log file to write to.
23452 @item @code{loglevel} (default: @samp{"error"})
23453 Log level to output logs. Possible values: @samp{"silent"}, @samp{"error"},
23454 @samp{"info"} and @samp{"debug"}.
23460 @node Sound Services
23461 @subsection Sound Services
23463 @cindex sound support
23465 @cindex PulseAudio, sound support
23467 The @code{(gnu services sound)} module provides a service to configure the
23468 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
23469 preferred ALSA output driver.
23471 @deffn {Scheme Variable} alsa-service-type
23472 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
23473 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
23474 configuration file. The value for this type is a @command{alsa-configuration}
23475 record as in this example:
23478 (service alsa-service-type)
23481 See below for details about @code{alsa-configuration}.
23484 @deftp {Data Type} alsa-configuration
23485 Data type representing the configuration for @code{alsa-service}.
23488 @item @code{alsa-plugins} (default: @var{alsa-plugins})
23489 @code{alsa-plugins} package to use.
23491 @item @code{pulseaudio?} (default: @var{#t})
23492 Whether ALSA applications should transparently be made to use the
23493 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
23495 Using PulseAudio allows you to run several sound-producing applications
23496 at the same time and to individual control them @i{via}
23497 @command{pavucontrol}, among other things.
23499 @item @code{extra-options} (default: @var{""})
23500 String to append to the @file{/etc/asound.conf} file.
23505 Individual users who want to override the system configuration of ALSA can do
23506 it with the @file{~/.asoundrc} file:
23509 # In guix, we have to specify the absolute path for plugins.
23511 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
23514 # Routing ALSA to jack:
23515 # <http://jackaudio.org/faq/routing_alsa.html>.
23519 0 system:playback_1
23520 1 system:playback_2
23537 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
23540 @deffn {Scheme Variable} pulseaudio-service-type
23541 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
23542 sound server. It exists to allow system overrides of the default settings
23543 via @code{pulseaudio-configuration}, see below.
23546 This service overrides per-user configuration files. If you want
23547 PulseAudio to honor configuration files in @file{~/.config/pulse} you
23548 have to unset the environment variables @env{PULSE_CONFIG} and
23549 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
23553 This service on its own does not ensure, that the @code{pulseaudio} package
23554 exists on your machine. It merely adds configuration files for it, as
23555 detailed below. In the (admittedly unlikely) case, that you find yourself
23556 without a @code{pulseaudio} package, consider enabling it through the
23557 @code{alsa-service-type} above.
23561 @deftp {Data Type} pulseaudio-configuration
23562 Data type representing the configuration for @code{pulseaudio-service}.
23565 @item @code{client-conf} (default: @code{'()})
23566 List of settings to set in @file{client.conf}.
23567 Accepts a list of strings or symbol-value pairs. A string will be
23568 inserted as-is with a newline added. A pair will be formatted as
23569 ``key = value'', again with a newline added.
23571 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
23572 List of settings to set in @file{daemon.conf}, formatted just like
23575 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
23576 Script file to use as @file{default.pa}. In case the
23577 @code{extra-script-files} field below is used, an @code{.include}
23578 directive pointing to @file{/etc/pulse/default.pa.d} is appended to the
23581 @item @code{extra-script-files} (default: @code{'()})
23582 A list of file-like objects defining extra PulseAudio scripts to run at
23583 the initialization of the @command{pulseaudio} daemon, after the main
23584 @code{script-file}. The scripts are deployed to the
23585 @file{/etc/pulse/default.pa.d} directory; they should have the
23586 @samp{.pa} file name extension. For a reference of the available
23587 commands, refer to @command{man pulse-cli-syntax}.
23589 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
23590 Script file to use as @file{system.pa}.
23593 The example below sets the default PulseAudio card profile, the default
23594 sink and the default source to use for a old SoundBlaster Audigy sound
23597 (pulseaudio-configuration
23598 (extra-script-files
23599 (list (plain-file "audigy.pa"
23601 set-card-profile alsa_card.pci-0000_01_01.0 \
23602 output:analog-surround-40+input:analog-mono
23603 set-default-source alsa_input.pci-0000_01_01.0.analog-mono
23604 set-default-sink alsa_output.pci-0000_01_01.0.analog-surround-40\n")))))
23607 Note that @code{pulseaudio-service-type} is part of
23608 @code{%desktop-services}; if your operating system declaration was
23609 derived from one of the desktop templates, you'll want to adjust the
23610 above example to modify the existing @code{pulseaudio-service-type} via
23611 @code{modify-services} (@pxref{Service Reference,
23612 @code{modify-services}}), instead of defining a new one.
23616 @deffn {Scheme Variable} ladspa-service-type
23617 This service sets the @var{LADSPA_PATH} variable, so that programs, which
23618 respect it, e.g. PulseAudio, can load LADSPA plugins.
23620 The following example will setup the service to enable modules from the
23621 @code{swh-plugins} package:
23624 (service ladspa-service-type
23625 (ladspa-configuration (plugins (list swh-plugins))))
23628 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
23633 @node Database Services
23634 @subsection Database Services
23638 The @code{(gnu services databases)} module provides the following services.
23640 @subsubheading PostgreSQL
23642 The following example describes a PostgreSQL service with the default
23646 (service postgresql-service-type
23647 (postgresql-configuration
23648 (postgresql postgresql-10)))
23651 If the services fails to start, it may be due to an incompatible
23652 cluster already present in @var{data-directory}. Adjust it (or, if you
23653 don't need the cluster anymore, delete @var{data-directory}), then
23654 restart the service.
23656 Peer authentication is used by default and the @code{postgres} user
23657 account has no shell, which prevents the direct execution of @code{psql}
23658 commands as this user. To use @code{psql}, you can temporarily log in
23659 as @code{postgres} using a shell, create a PostgreSQL superuser with the
23660 same name as one of the system users and then create the associated
23664 sudo -u postgres -s /bin/sh
23665 createuser --interactive
23666 createdb $MY_USER_LOGIN # Replace appropriately.
23669 @deftp {Data Type} postgresql-configuration
23670 Data type representing the configuration for the
23671 @code{postgresql-service-type}.
23674 @item @code{postgresql}
23675 PostgreSQL package to use for the service.
23677 @item @code{port} (default: @code{5432})
23678 Port on which PostgreSQL should listen.
23680 @item @code{locale} (default: @code{"en_US.utf8"})
23681 Locale to use as the default when creating the database cluster.
23683 @item @code{config-file} (default: @code{(postgresql-config-file)})
23684 The configuration file to use when running PostgreSQL@. The default
23685 behaviour uses the postgresql-config-file record with the default values
23688 @item @code{log-directory} (default: @code{"/var/log/postgresql"})
23689 The directory where @command{pg_ctl} output will be written in a file
23690 named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
23691 configuration errors for instance.
23693 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
23694 Directory in which to store the data.
23696 @item @code{extension-packages} (default: @code{'()})
23697 @cindex postgresql extension-packages
23698 Additional extensions are loaded from packages listed in
23699 @var{extension-packages}. Extensions are available at runtime. For instance,
23700 to create a geographic database using the @code{postgis} extension, a user can
23701 configure the postgresql-service as in this example:
23705 (use-package-modules databases geo)
23709 ;; postgresql is required to run `psql' but postgis is not required for
23710 ;; proper operation.
23711 (packages (cons* postgresql %base-packages))
23714 (service postgresql-service-type
23715 (postgresql-configuration
23716 (postgresql postgresql-10)
23717 (extension-packages (list postgis))))
23721 Then the extension becomes visible and you can initialise an empty geographic
23722 database in this way:
23726 > create database postgistest;
23727 > \connect postgistest;
23728 > create extension postgis;
23729 > create extension postgis_topology;
23732 There is no need to add this field for contrib extensions such as hstore or
23733 dblink as they are already loadable by postgresql. This field is only
23734 required to add extensions provided by other packages.
23739 @deftp {Data Type} postgresql-config-file
23740 Data type representing the PostgreSQL configuration file. As shown in
23741 the following example, this can be used to customize the configuration
23742 of PostgreSQL@. Note that you can use any G-expression or filename in
23743 place of this record, if you already have a configuration file you'd
23744 like to use for example.
23747 (service postgresql-service-type
23748 (postgresql-configuration
23750 (postgresql-config-file
23751 (log-destination "stderr")
23753 (plain-file "pg_hba.conf"
23755 local all all trust
23756 host all all 127.0.0.1/32 md5
23757 host all all ::1/128 md5"))
23759 '(("session_preload_libraries" "auto_explain")
23760 ("random_page_cost" 2)
23761 ("auto_explain.log_min_duration" "100 ms")
23762 ("work_mem" "500 MB")
23763 ("logging_collector" #t)
23764 ("log_directory" "/var/log/postgresql")))))))
23768 @item @code{log-destination} (default: @code{"syslog"})
23769 The logging method to use for PostgreSQL@. Multiple values are accepted,
23770 separated by commas.
23772 @item @code{hba-file} (default: @code{%default-postgres-hba})
23773 Filename or G-expression for the host-based authentication
23776 @item @code{ident-file} (default: @code{%default-postgres-ident})
23777 Filename or G-expression for the user name mapping configuration.
23779 @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
23780 Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
23781 is to listen for connections from client applications. If set to
23782 @code{""} PostgreSQL does not listen on any Unix-domain sockets, in
23783 which case only TCP/IP sockets can be used to connect to the server.
23785 By default, the @code{#false} value means the PostgreSQL default value
23786 will be used, which is currently @samp{/tmp}.
23788 @item @code{extra-config} (default: @code{'()})
23789 List of additional keys and values to include in the PostgreSQL config
23790 file. Each entry in the list should be a list where the first element
23791 is the key, and the remaining elements are the values.
23793 The values can be numbers, booleans or strings and will be mapped to
23794 PostgreSQL parameters types @code{Boolean}, @code{String},
23795 @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
23796 @uref{https://www.postgresql.org/docs/current/config-setting.html,
23802 @deffn {Scheme Variable} postgresql-role-service-type
23803 This service allows to create PostgreSQL roles and databases after
23804 PostgreSQL service start. Here is an example of its use.
23807 (service postgresql-role-service-type
23808 (postgresql-role-configuration
23810 (list (postgresql-role
23812 (create-database? #t))))))
23815 This service can be extended with extra roles, as in this
23819 (service-extension postgresql-role-service-type
23820 (const (postgresql-role
23822 (create-database? #t))))
23826 @deftp {Data Type} postgresql-role
23827 PostgreSQL manages database access permissions using the concept of
23828 roles. A role can be thought of as either a database user, or a group
23829 of database users, depending on how the role is set up. Roles can own
23830 database objects (for example, tables) and can assign privileges on
23831 those objects to other roles to control who has access to which objects.
23837 @item @code{permissions} (default: @code{'(createdb login)})
23838 The role permissions list. Supported permissions are @code{bypassrls},
23839 @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
23842 @item @code{create-database?} (default: @code{#f})
23843 Whether to create a database with the same name as the role.
23848 @deftp {Data Type} postgresql-role-configuration
23849 Data type representing the configuration of
23850 @var{postgresql-role-service-type}.
23853 @item @code{host} (default: @code{"/var/run/postgresql"})
23854 The PostgreSQL host to connect to.
23856 @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
23857 File name of the log file.
23859 @item @code{roles} (default: @code{'()})
23860 The initial PostgreSQL roles to create.
23864 @subsubheading MariaDB/MySQL
23866 @defvr {Scheme Variable} mysql-service-type
23867 This is the service type for a MySQL or MariaDB database server. Its value
23868 is a @code{mysql-configuration} object that specifies which package to use,
23869 as well as various settings for the @command{mysqld} daemon.
23872 @deftp {Data Type} mysql-configuration
23873 Data type representing the configuration of @var{mysql-service-type}.
23876 @item @code{mysql} (default: @var{mariadb})
23877 Package object of the MySQL database server, can be either @var{mariadb}
23880 For MySQL, a temporary root password will be displayed at activation time.
23881 For MariaDB, the root password is empty.
23883 @item @code{bind-address} (default: @code{"127.0.0.1"})
23884 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
23885 to bind to all available network interfaces.
23887 @item @code{port} (default: @code{3306})
23888 TCP port on which the database server listens for incoming connections.
23890 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
23891 Socket file to use for local (non-network) connections.
23893 @item @code{extra-content} (default: @code{""})
23894 Additional settings for the @file{my.cnf} configuration file.
23896 @item @code{extra-environment} (default: @code{#~'()})
23897 List of environment variables passed to the @command{mysqld} process.
23899 @item @code{auto-upgrade?} (default: @code{#t})
23900 Whether to automatically run @command{mysql_upgrade} after starting the
23901 service. This is necessary to upgrade the @dfn{system schema} after
23902 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
23903 be disabled if you would rather do that manually.
23908 @subsubheading Memcached
23910 @defvr {Scheme Variable} memcached-service-type
23911 This is the service type for the @uref{https://memcached.org/,
23912 Memcached} service, which provides a distributed in memory cache. The
23913 value for the service type is a @code{memcached-configuration} object.
23917 (service memcached-service-type)
23920 @deftp {Data Type} memcached-configuration
23921 Data type representing the configuration of memcached.
23924 @item @code{memcached} (default: @code{memcached})
23925 The Memcached package to use.
23927 @item @code{interfaces} (default: @code{'("0.0.0.0")})
23928 Network interfaces on which to listen.
23930 @item @code{tcp-port} (default: @code{11211})
23931 Port on which to accept connections.
23933 @item @code{udp-port} (default: @code{11211})
23934 Port on which to accept UDP connections on, a value of 0 will disable
23935 listening on a UDP socket.
23937 @item @code{additional-options} (default: @code{'()})
23938 Additional command line options to pass to @code{memcached}.
23942 @subsubheading Redis
23944 @defvr {Scheme Variable} redis-service-type
23945 This is the service type for the @uref{https://redis.io/, Redis}
23946 key/value store, whose value is a @code{redis-configuration} object.
23949 @deftp {Data Type} redis-configuration
23950 Data type representing the configuration of redis.
23953 @item @code{redis} (default: @code{redis})
23954 The Redis package to use.
23956 @item @code{bind} (default: @code{"127.0.0.1"})
23957 Network interface on which to listen.
23959 @item @code{port} (default: @code{6379})
23960 Port on which to accept connections on, a value of 0 will disable
23961 listening on a TCP socket.
23963 @item @code{working-directory} (default: @code{"/var/lib/redis"})
23964 Directory in which to store the database and related files.
23968 @node Mail Services
23969 @subsection Mail Services
23973 The @code{(gnu services mail)} module provides Guix service definitions
23974 for email services: IMAP, POP3, and LMTP servers, as well as mail
23975 transport agents (MTAs). Lots of acronyms! These services are detailed
23976 in the subsections below.
23978 @subsubheading Dovecot Service
23980 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
23981 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
23984 By default, Dovecot does not need much configuration; the default
23985 configuration object created by @code{(dovecot-configuration)} will
23986 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
23987 certificate will be generated for TLS-protected connections, though
23988 Dovecot will also listen on cleartext ports by default. There are a
23989 number of options, though, which mail administrators might need to change,
23990 and as is the case with other services, Guix allows the system
23991 administrator to specify these parameters via a uniform Scheme interface.
23993 For example, to specify that mail is located at @code{maildir~/.mail},
23994 one would instantiate the Dovecot service like this:
23997 (dovecot-service #:config
23998 (dovecot-configuration
23999 (mail-location "maildir:~/.mail")))
24002 The available configuration parameters follow. Each parameter
24003 definition is preceded by its type; for example, @samp{string-list foo}
24004 indicates that the @code{foo} parameter should be specified as a list of
24005 strings. There is also a way to specify the configuration as a string,
24006 if you have an old @code{dovecot.conf} file that you want to port over
24007 from some other system; see the end for more details.
24009 @c The following documentation was initially generated by
24010 @c (generate-documentation) in (gnu services mail). Manually maintained
24011 @c documentation is better, so we shouldn't hesitate to edit below as
24012 @c needed. However if the change you want to make to this documentation
24013 @c can be done in an automated way, it's probably easier to change
24014 @c (generate-documentation) than to make it below and have to deal with
24015 @c the churn as dovecot updates.
24017 Available @code{dovecot-configuration} fields are:
24019 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
24020 The dovecot package.
24023 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
24024 A list of IPs or hosts where to listen for connections. @samp{*}
24025 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
24026 interfaces. If you want to specify non-default ports or anything more
24027 complex, customize the address and port fields of the
24028 @samp{inet-listener} of the specific services you are interested in.
24031 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
24032 List of protocols we want to serve. Available protocols include
24033 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
24035 Available @code{protocol-configuration} fields are:
24037 @deftypevr {@code{protocol-configuration} parameter} string name
24038 The name of the protocol.
24041 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
24042 UNIX socket path to the master authentication server to find users.
24043 This is used by imap (for shared users) and lda.
24044 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
24047 @deftypevr {@code{protocol-configuration} parameter} boolean imap-metadata?
24048 Whether to enable the @code{IMAP METADATA} extension as defined in
24049 @uref{https://tools.ietf.org/html/rfc5464,RFC@tie{}5464}, which provides
24050 a means for clients to set and retrieve per-mailbox, per-user metadata
24051 and annotations over IMAP.
24053 If this is @samp{#t}, you must also specify a dictionary @i{via} the
24054 @code{mail-attribute-dict} setting.
24056 Defaults to @samp{#f}.
24060 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-notify-capabilities
24061 Which NOTIFY capabilities to report to clients that first connect to
24062 the ManageSieve service, before authentication. These may differ from the
24063 capabilities offered to authenticated users. If this field is left empty,
24064 report what the Sieve interpreter supports by default.
24066 Defaults to @samp{()}.
24069 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-sieve-capability
24070 Which SIEVE 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{()}.
24079 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
24080 Space separated list of plugins to load.
24083 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
24084 Maximum number of IMAP connections allowed for a user from each IP
24085 address. NOTE: The username is compared case-sensitively.
24086 Defaults to @samp{10}.
24091 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
24092 List of services to enable. Available services include @samp{imap},
24093 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
24096 Available @code{service-configuration} fields are:
24098 @deftypevr {@code{service-configuration} parameter} string kind
24099 The service kind. Valid values include @code{director},
24100 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
24101 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
24102 @code{tcpwrap}, @code{quota-warning}, or anything else.
24105 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
24106 Listeners for the service. A listener is either a
24107 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
24108 an @code{inet-listener-configuration}.
24109 Defaults to @samp{()}.
24111 Available @code{unix-listener-configuration} fields are:
24113 @deftypevr {@code{unix-listener-configuration} parameter} string path
24114 Path to the file, relative to @code{base-dir} field. This is also used as
24118 @deftypevr {@code{unix-listener-configuration} parameter} string mode
24119 The access mode for the socket.
24120 Defaults to @samp{"0600"}.
24123 @deftypevr {@code{unix-listener-configuration} parameter} string user
24124 The user to own the socket.
24125 Defaults to @samp{""}.
24128 @deftypevr {@code{unix-listener-configuration} parameter} string group
24129 The group to own the socket.
24130 Defaults to @samp{""}.
24134 Available @code{fifo-listener-configuration} fields are:
24136 @deftypevr {@code{fifo-listener-configuration} parameter} string path
24137 Path to the file, relative to @code{base-dir} field. This is also used as
24141 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
24142 The access mode for the socket.
24143 Defaults to @samp{"0600"}.
24146 @deftypevr {@code{fifo-listener-configuration} parameter} string user
24147 The user to own the socket.
24148 Defaults to @samp{""}.
24151 @deftypevr {@code{fifo-listener-configuration} parameter} string group
24152 The group to own the socket.
24153 Defaults to @samp{""}.
24157 Available @code{inet-listener-configuration} fields are:
24159 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
24160 The protocol to listen for.
24163 @deftypevr {@code{inet-listener-configuration} parameter} string address
24164 The address on which to listen, or empty for all addresses.
24165 Defaults to @samp{""}.
24168 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
24169 The port on which to listen.
24172 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
24173 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
24175 Defaults to @samp{#t}.
24180 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
24181 Maximum number of simultaneous client connections per process. Once
24182 this number of connections is received, the next incoming connection
24183 will prompt Dovecot to spawn another process. If set to 0,
24184 @code{default-client-limit} is used instead.
24186 Defaults to @samp{0}.
24190 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
24191 Number of connections to handle before starting a new process.
24192 Typically the only useful values are 0 (unlimited) or 1. 1 is more
24193 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
24194 Defaults to @samp{1}.
24198 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
24199 Maximum number of processes that can exist for this service. If set to
24200 0, @code{default-process-limit} is used instead.
24202 Defaults to @samp{0}.
24206 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
24207 Number of processes to always keep waiting for more connections.
24208 Defaults to @samp{0}.
24211 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
24212 If you set @samp{service-count 0}, you probably need to grow
24214 Defaults to @samp{256000000}.
24219 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
24220 Dict configuration, as created by the @code{dict-configuration}
24223 Available @code{dict-configuration} fields are:
24225 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
24226 A list of key-value pairs that this dict should hold.
24227 Defaults to @samp{()}.
24232 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
24233 A list of passdb configurations, each one created by the
24234 @code{passdb-configuration} constructor.
24236 Available @code{passdb-configuration} fields are:
24238 @deftypevr {@code{passdb-configuration} parameter} string driver
24239 The driver that the passdb should use. Valid values include
24240 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
24242 Defaults to @samp{"pam"}.
24245 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
24246 Space separated list of arguments to the passdb driver.
24247 Defaults to @samp{""}.
24252 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
24253 List of userdb configurations, each one created by the
24254 @code{userdb-configuration} constructor.
24256 Available @code{userdb-configuration} fields are:
24258 @deftypevr {@code{userdb-configuration} parameter} string driver
24259 The driver that the userdb should use. Valid values include
24260 @samp{passwd} and @samp{static}.
24261 Defaults to @samp{"passwd"}.
24264 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
24265 Space separated list of arguments to the userdb driver.
24266 Defaults to @samp{""}.
24269 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
24270 Override fields from passwd.
24271 Defaults to @samp{()}.
24276 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
24277 Plug-in configuration, created by the @code{plugin-configuration}
24281 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
24282 List of namespaces. Each item in the list is created by the
24283 @code{namespace-configuration} constructor.
24285 Available @code{namespace-configuration} fields are:
24287 @deftypevr {@code{namespace-configuration} parameter} string name
24288 Name for this namespace.
24291 @deftypevr {@code{namespace-configuration} parameter} string type
24292 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
24293 Defaults to @samp{"private"}.
24296 @deftypevr {@code{namespace-configuration} parameter} string separator
24297 Hierarchy separator to use. You should use the same separator for
24298 all namespaces or some clients get confused. @samp{/} is usually a good
24299 one. The default however depends on the underlying mail storage
24301 Defaults to @samp{""}.
24304 @deftypevr {@code{namespace-configuration} parameter} string prefix
24305 Prefix required to access this namespace. This needs to be
24306 different for all namespaces. For example @samp{Public/}.
24307 Defaults to @samp{""}.
24310 @deftypevr {@code{namespace-configuration} parameter} string location
24311 Physical location of the mailbox. This is in the same format as
24312 mail_location, which is also the default for it.
24313 Defaults to @samp{""}.
24316 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
24317 There can be only one INBOX, and this setting defines which
24319 Defaults to @samp{#f}.
24322 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
24323 If namespace is hidden, it's not advertised to clients via NAMESPACE
24324 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
24325 useful when converting from another server with different namespaces
24326 which you want to deprecate but still keep working. For example you can
24327 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
24329 Defaults to @samp{#f}.
24332 @deftypevr {@code{namespace-configuration} parameter} boolean list?
24333 Show the mailboxes under this namespace with the LIST command. This
24334 makes the namespace visible for clients that do not support the NAMESPACE
24335 extension. The special @code{children} value lists child mailboxes, but
24336 hides the namespace prefix.
24337 Defaults to @samp{#t}.
24340 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
24341 Namespace handles its own subscriptions. If set to @code{#f}, the
24342 parent namespace handles them. The empty prefix should always have this
24344 Defaults to @samp{#t}.
24347 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
24348 List of predefined mailboxes in this namespace.
24349 Defaults to @samp{()}.
24351 Available @code{mailbox-configuration} fields are:
24353 @deftypevr {@code{mailbox-configuration} parameter} string name
24354 Name for this mailbox.
24357 @deftypevr {@code{mailbox-configuration} parameter} string auto
24358 @samp{create} will automatically create this mailbox.
24359 @samp{subscribe} will both create and subscribe to the mailbox.
24360 Defaults to @samp{"no"}.
24363 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
24364 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
24365 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
24366 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
24367 Defaults to @samp{()}.
24374 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
24375 Base directory where to store runtime data.
24376 Defaults to @samp{"/var/run/dovecot/"}.
24379 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
24380 Greeting message for clients.
24381 Defaults to @samp{"Dovecot ready."}.
24384 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
24385 List of trusted network ranges. Connections from these IPs are
24386 allowed to override their IP addresses and ports (for logging and for
24387 authentication checks). @samp{disable-plaintext-auth} is also ignored
24388 for these networks. Typically you would specify your IMAP proxy servers
24390 Defaults to @samp{()}.
24393 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
24394 List of login access check sockets (e.g.@: tcpwrap).
24395 Defaults to @samp{()}.
24398 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
24399 Show more verbose process titles (in ps). Currently shows user name
24400 and IP address. Useful for seeing who is actually using the IMAP
24401 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
24403 Defaults to @samp{#f}.
24406 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
24407 Should all processes be killed when Dovecot master process shuts down.
24408 Setting this to @code{#f} means that Dovecot can be upgraded without
24409 forcing existing client connections to close (although that could also
24410 be a problem if the upgrade is e.g.@: due to a security fix).
24411 Defaults to @samp{#t}.
24414 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
24415 If non-zero, run mail commands via this many connections to doveadm
24416 server, instead of running them directly in the same process.
24417 Defaults to @samp{0}.
24420 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
24421 UNIX socket or host:port used for connecting to doveadm server.
24422 Defaults to @samp{"doveadm-server"}.
24425 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
24426 List of environment variables that are preserved on Dovecot startup
24427 and passed down to all of its child processes. You can also give
24428 key=value pairs to always set specific settings.
24431 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
24432 Disable LOGIN command and all other plaintext authentications unless
24433 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
24434 matches the local IP (i.e.@: you're connecting from the same computer),
24435 the connection is considered secure and plaintext authentication is
24436 allowed. See also ssl=required setting.
24437 Defaults to @samp{#t}.
24440 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
24441 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
24442 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
24443 for caching to be used.
24444 Defaults to @samp{0}.
24447 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
24448 Time to live for cached data. After TTL expires the cached record
24449 is no longer used, *except* if the main database lookup returns internal
24450 failure. We also try to handle password changes automatically: If
24451 user's previous authentication was successful, but this one wasn't, the
24452 cache isn't used. For now this works only with plaintext
24454 Defaults to @samp{"1 hour"}.
24457 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
24458 TTL for negative hits (user not found, password mismatch).
24459 0 disables caching them completely.
24460 Defaults to @samp{"1 hour"}.
24463 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
24464 List of realms for SASL authentication mechanisms that need them.
24465 You can leave it empty if you don't want to support multiple realms.
24466 Many clients simply use the first one listed here, so keep the default
24468 Defaults to @samp{()}.
24471 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
24472 Default realm/domain to use if none was specified. This is used for
24473 both SASL realms and appending @@domain to username in plaintext
24475 Defaults to @samp{""}.
24478 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
24479 List of allowed characters in username. If the user-given username
24480 contains a character not listed in here, the login automatically fails.
24481 This is just an extra check to make sure user can't exploit any
24482 potential quote escaping vulnerabilities with SQL/LDAP databases. If
24483 you want to allow all characters, set this value to empty.
24484 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
24487 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
24488 Username character translations before it's looked up from
24489 databases. The value contains series of from -> to characters. For
24490 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
24491 translated to @samp{@@}.
24492 Defaults to @samp{""}.
24495 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
24496 Username formatting before it's looked up from databases. You can
24497 use the standard variables here, e.g.@: %Lu would lowercase the username,
24498 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
24499 change the @samp{@@} into @samp{-AT-}. This translation is done after
24500 @samp{auth-username-translation} changes.
24501 Defaults to @samp{"%Lu"}.
24504 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
24505 If you want to allow master users to log in by specifying the master
24506 username within the normal username string (i.e.@: not using SASL
24507 mechanism's support for it), you can specify the separator character
24508 here. The format is then <username><separator><master username>.
24509 UW-IMAP uses @samp{*} as the separator, so that could be a good
24511 Defaults to @samp{""}.
24514 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
24515 Username to use for users logging in with ANONYMOUS SASL
24517 Defaults to @samp{"anonymous"}.
24520 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
24521 Maximum number of dovecot-auth worker processes. They're used to
24522 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
24523 They're automatically created and destroyed as needed.
24524 Defaults to @samp{30}.
24527 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
24528 Host name to use in GSSAPI principal names. The default is to use
24529 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
24530 allow all keytab entries.
24531 Defaults to @samp{""}.
24534 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
24535 Kerberos keytab to use for the GSSAPI mechanism. Will use the
24536 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
24537 need to change the auth service to run as root to be able to read this
24539 Defaults to @samp{""}.
24542 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
24543 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
24544 and @samp{ntlm-auth} helper.
24545 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
24546 Defaults to @samp{#f}.
24549 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
24550 Path for Samba's @samp{ntlm-auth} helper binary.
24551 Defaults to @samp{"/usr/bin/ntlm_auth"}.
24554 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
24555 Time to delay before replying to failed authentications.
24556 Defaults to @samp{"2 secs"}.
24559 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
24560 Require a valid SSL client certificate or the authentication
24562 Defaults to @samp{#f}.
24565 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
24566 Take the username from client's SSL certificate, using
24567 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
24569 Defaults to @samp{#f}.
24572 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
24573 List of wanted authentication mechanisms. Supported mechanisms are:
24574 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
24575 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
24576 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
24577 @samp{disable-plaintext-auth} setting.
24580 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
24581 List of IPs or hostnames to all director servers, including ourself.
24582 Ports can be specified as ip:port. The default port is the same as what
24583 director service's @samp{inet-listener} is using.
24584 Defaults to @samp{()}.
24587 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
24588 List of IPs or hostnames to all backend mail servers. Ranges are
24589 allowed too, like 10.0.0.10-10.0.0.30.
24590 Defaults to @samp{()}.
24593 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
24594 How long to redirect users to a specific server after it no longer
24595 has any connections.
24596 Defaults to @samp{"15 min"}.
24599 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
24600 How the username is translated before being hashed. Useful values
24601 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
24602 are shared within domain.
24603 Defaults to @samp{"%Lu"}.
24606 @deftypevr {@code{dovecot-configuration} parameter} string log-path
24607 Log file to use for error messages. @samp{syslog} logs to syslog,
24608 @samp{/dev/stderr} logs to stderr.
24609 Defaults to @samp{"syslog"}.
24612 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
24613 Log file to use for informational messages. Defaults to
24615 Defaults to @samp{""}.
24618 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
24619 Log file to use for debug messages. Defaults to
24620 @samp{info-log-path}.
24621 Defaults to @samp{""}.
24624 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
24625 Syslog facility to use if you're logging to syslog. Usually if you
24626 don't want to use @samp{mail}, you'll use local0..local7. Also other
24627 standard facilities are supported.
24628 Defaults to @samp{"mail"}.
24631 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
24632 Log unsuccessful authentication attempts and the reasons why they
24634 Defaults to @samp{#f}.
24637 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
24638 In case of password mismatches, log the attempted password. Valid
24639 values are no, plain and sha1. sha1 can be useful for detecting brute
24640 force password attempts vs. user simply trying the same password over
24641 and over again. You can also truncate the value to n chars by appending
24642 ":n" (e.g.@: sha1:6).
24643 Defaults to @samp{"no"}.
24646 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
24647 Even more verbose logging for debugging purposes. Shows for example
24649 Defaults to @samp{#f}.
24652 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
24653 In case of password mismatches, log the passwords and used scheme so
24654 the problem can be debugged. Enabling this also enables
24656 Defaults to @samp{#f}.
24659 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
24660 Enable mail process debugging. This can help you figure out why
24661 Dovecot isn't finding your mails.
24662 Defaults to @samp{#f}.
24665 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
24666 Show protocol level SSL errors.
24667 Defaults to @samp{#f}.
24670 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
24671 Prefix for each line written to log file. % codes are in
24672 strftime(3) format.
24673 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
24676 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
24677 List of elements we want to log. The elements which have a
24678 non-empty variable value are joined together to form a comma-separated
24682 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
24683 Login log format. %s contains @samp{login-log-format-elements}
24684 string, %$ contains the data we want to log.
24685 Defaults to @samp{"%$: %s"}.
24688 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
24689 Log prefix for mail processes. See doc/wiki/Variables.txt for list
24690 of possible variables you can use.
24691 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
24694 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
24695 Format to use for logging mail deliveries. You can use variables:
24698 Delivery status message (e.g.@: @samp{saved to INBOX})
24710 Defaults to @samp{"msgid=%m: %$"}.
24713 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
24714 Location for users' mailboxes. The default is empty, which means
24715 that Dovecot tries to find the mailboxes automatically. This won't work
24716 if the user doesn't yet have any mail, so you should explicitly tell
24717 Dovecot the full location.
24719 If you're using mbox, giving a path to the INBOX
24720 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
24721 where the other mailboxes are kept. This is called the @emph{root mail
24722 directory}, and it must be the first path given in the
24723 @samp{mail-location} setting.
24725 There are a few special variables you can use, e.g.:
24731 user part in user@@domain, same as %u if there's no domain
24733 domain part in user@@domain, empty if there's no domain
24738 See doc/wiki/Variables.txt for full list. Some examples:
24740 @item maildir:~/Maildir
24741 @item mbox:~/mail:INBOX=/var/mail/%u
24742 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
24744 Defaults to @samp{""}.
24747 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
24748 System user and group used to access mails. If you use multiple,
24749 userdb can override these by returning uid or gid fields. You can use
24750 either numbers or names. <doc/wiki/UserIds.txt>.
24751 Defaults to @samp{""}.
24754 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
24756 Defaults to @samp{""}.
24759 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
24760 Group to enable temporarily for privileged operations. Currently
24761 this is used only with INBOX when either its initial creation or
24762 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
24764 Defaults to @samp{""}.
24767 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
24768 Grant access to these supplementary groups for mail processes.
24769 Typically these are used to set up access to shared mailboxes. Note
24770 that it may be dangerous to set these if users can create symlinks
24771 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
24772 could allow a user to delete others' mailboxes, or @code{ln -s
24773 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
24777 @deftypevr {@code{dovecot-configuration} parameter} string mail-attribute-dict
24778 The location of a dictionary used to store @code{IMAP METADATA}
24779 as defined by @uref{https://tools.ietf.org/html/rfc5464, RFC@tie{}5464}.
24781 The IMAP METADATA commands are available only if the ``imap''
24782 protocol configuration's @code{imap-metadata?} field is @samp{#t}.
24784 Defaults to @samp{""}.
24788 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
24789 Allow full file system access to clients. There's no access checks
24790 other than what the operating system does for the active UID/GID@. It
24791 works with both maildir and mboxes, allowing you to prefix mailboxes
24792 names with e.g.@: @file{/path/} or @file{~user/}.
24793 Defaults to @samp{#f}.
24796 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
24797 Don't use @code{mmap()} at all. This is required if you store indexes to
24798 shared file systems (NFS or clustered file system).
24799 Defaults to @samp{#f}.
24802 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
24803 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
24804 supports @samp{O_EXCL} since version 3, so this should be safe to use
24805 nowadays by default.
24806 Defaults to @samp{#t}.
24809 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
24810 When to use fsync() or fdatasync() calls:
24813 Whenever necessary to avoid losing important data
24815 Useful with e.g.@: NFS when @code{write()}s are delayed
24817 Never use it (best performance, but crashes can lose data).
24819 Defaults to @samp{"optimized"}.
24822 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
24823 Mail storage exists in NFS@. Set this to yes to make Dovecot flush
24824 NFS caches whenever needed. If you're using only a single mail server
24826 Defaults to @samp{#f}.
24829 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
24830 Mail index files also exist in NFS@. Setting this to yes requires
24831 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
24832 Defaults to @samp{#f}.
24835 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
24836 Locking method for index files. Alternatives are fcntl, flock and
24837 dotlock. Dotlocking uses some tricks which may create more disk I/O
24838 than other locking methods. NFS users: flock doesn't work, remember to
24839 change @samp{mmap-disable}.
24840 Defaults to @samp{"fcntl"}.
24843 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
24844 Directory in which LDA/LMTP temporarily stores incoming mails >128
24846 Defaults to @samp{"/tmp"}.
24849 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
24850 Valid UID range for users. This is mostly to make sure that users can't
24851 log in as daemons or other system users. Note that denying root logins is
24852 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
24854 Defaults to @samp{500}.
24857 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
24859 Defaults to @samp{0}.
24862 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
24863 Valid GID range for users. Users having non-valid GID as primary group ID
24864 aren't allowed to log in. If user belongs to supplementary groups with
24865 non-valid GIDs, those groups are not set.
24866 Defaults to @samp{1}.
24869 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
24871 Defaults to @samp{0}.
24874 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
24875 Maximum allowed length for mail keyword name. It's only forced when
24876 trying to create new keywords.
24877 Defaults to @samp{50}.
24880 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
24881 List of directories under which chrooting is allowed for mail
24882 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
24883 too). This setting doesn't affect @samp{login-chroot}
24884 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
24885 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
24886 which local users can modify, that may lead to root exploit. Usually
24887 this should be done only if you don't allow shell access for users.
24888 <doc/wiki/Chrooting.txt>.
24889 Defaults to @samp{()}.
24892 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
24893 Default chroot directory for mail processes. This can be overridden
24894 for specific users in user database by giving @samp{/./} in user's home
24895 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
24896 there is no real need to do chrooting, Dovecot doesn't allow users to
24897 access files outside their mail directory anyway. If your home
24898 directories are prefixed with the chroot directory, append @samp{/.} to
24899 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
24900 Defaults to @samp{""}.
24903 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
24904 UNIX socket path to master authentication server to find users.
24905 This is used by imap (for shared users) and lda.
24906 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
24909 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
24910 Directory where to look up mail plugins.
24911 Defaults to @samp{"/usr/lib/dovecot"}.
24914 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
24915 List of plugins to load for all services. Plugins specific to IMAP,
24916 LDA, etc.@: are added to this list in their own .conf files.
24917 Defaults to @samp{()}.
24920 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
24921 The minimum number of mails in a mailbox before updates are done to
24922 cache file. This allows optimizing Dovecot's behavior to do less disk
24923 writes at the cost of more disk reads.
24924 Defaults to @samp{0}.
24927 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
24928 When IDLE command is running, mailbox is checked once in a while to
24929 see if there are any new mails or other changes. This setting defines
24930 the minimum time to wait between those checks. Dovecot can also use
24931 dnotify, inotify and kqueue to find out immediately when changes
24933 Defaults to @samp{"30 secs"}.
24936 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
24937 Save mails with CR+LF instead of plain LF@. This makes sending those
24938 mails take less CPU, especially with sendfile() syscall with Linux and
24939 FreeBSD@. But it also creates a bit more disk I/O which may just make it
24940 slower. Also note that if other software reads the mboxes/maildirs,
24941 they may handle the extra CRs wrong and cause problems.
24942 Defaults to @samp{#f}.
24945 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
24946 By default LIST command returns all entries in maildir beginning
24947 with a dot. Enabling this option makes Dovecot return only entries
24948 which are directories. This is done by stat()ing each entry, so it
24949 causes more disk I/O.
24950 (For systems setting struct @samp{dirent->d_type} this check is free
24951 and it's done always regardless of this setting).
24952 Defaults to @samp{#f}.
24955 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
24956 When copying a message, do it with hard links whenever possible.
24957 This makes the performance much better, and it's unlikely to have any
24959 Defaults to @samp{#t}.
24962 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
24963 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
24964 directory only when its mtime changes unexpectedly or when we can't find
24965 the mail otherwise.
24966 Defaults to @samp{#f}.
24969 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
24970 Which locking methods to use for locking mbox. There are four
24975 Create <mailbox>.lock file. This is the oldest and most NFS-safe
24976 solution. If you want to use /var/mail/ like directory, the users will
24977 need write access to that directory.
24979 Same as dotlock, but if it fails because of permissions or because there
24980 isn't enough disk space, just skip it.
24982 Use this if possible. Works with NFS too if lockd is used.
24984 May not exist in all systems. Doesn't work with NFS.
24986 May not exist in all systems. Doesn't work with NFS.
24989 You can use multiple locking methods; if you do the order they're declared
24990 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
24991 locking methods as well. Some operating systems don't allow using some of
24992 them simultaneously.
24995 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
24999 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
25000 Maximum time to wait for lock (all of them) before aborting.
25001 Defaults to @samp{"5 mins"}.
25004 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
25005 If dotlock exists but the mailbox isn't modified in any way,
25006 override the lock file after this much time.
25007 Defaults to @samp{"2 mins"}.
25010 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
25011 When mbox changes unexpectedly we have to fully read it to find out
25012 what changed. If the mbox is large this can take a long time. Since
25013 the change is usually just a newly appended mail, it'd be faster to
25014 simply read the new mails. If this setting is enabled, Dovecot does
25015 this but still safely fallbacks to re-reading the whole mbox file
25016 whenever something in mbox isn't how it's expected to be. The only real
25017 downside to this setting is that if some other MUA changes message
25018 flags, Dovecot doesn't notice it immediately. Note that a full sync is
25019 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
25020 Defaults to @samp{#t}.
25023 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
25024 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
25025 EXAMINE, EXPUNGE or CHECK commands. If this is set,
25026 @samp{mbox-dirty-syncs} is ignored.
25027 Defaults to @samp{#f}.
25030 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
25031 Delay writing mbox headers until doing a full write sync (EXPUNGE
25032 and CHECK commands and when closing the mailbox). This is especially
25033 useful for POP3 where clients often delete all mails. The downside is
25034 that our changes aren't immediately visible to other MUAs.
25035 Defaults to @samp{#t}.
25038 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
25039 If mbox size is smaller than this (e.g.@: 100k), don't write index
25040 files. If an index file already exists it's still read, just not
25042 Defaults to @samp{0}.
25045 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
25046 Maximum dbox file size until it's rotated.
25047 Defaults to @samp{10000000}.
25050 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
25051 Maximum dbox file age until it's rotated. Typically in days. Day
25052 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
25054 Defaults to @samp{"1d"}.
25057 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
25058 When creating new mdbox files, immediately preallocate their size to
25059 @samp{mdbox-rotate-size}. This setting currently works only in Linux
25060 with some file systems (ext4, xfs).
25061 Defaults to @samp{#f}.
25064 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
25065 sdbox and mdbox support saving mail attachments to external files,
25066 which also allows single instance storage for them. Other backends
25067 don't support this for now.
25069 WARNING: This feature hasn't been tested much yet. Use at your own risk.
25071 Directory root where to store mail attachments. Disabled, if empty.
25072 Defaults to @samp{""}.
25075 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
25076 Attachments smaller than this aren't saved externally. It's also
25077 possible to write a plugin to disable saving specific attachments
25079 Defaults to @samp{128000}.
25082 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
25083 File system backend to use for saving attachments:
25086 No SiS done by Dovecot (but this might help FS's own deduplication)
25088 SiS with immediate byte-by-byte comparison during saving
25089 @item sis-queue posix
25090 SiS with delayed comparison and deduplication.
25092 Defaults to @samp{"sis posix"}.
25095 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
25096 Hash format to use in attachment filenames. You can add any text and
25097 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
25098 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
25099 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
25100 Defaults to @samp{"%@{sha1@}"}.
25103 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
25105 Defaults to @samp{100}.
25108 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
25110 Defaults to @samp{1000}.
25113 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
25114 Default VSZ (virtual memory size) limit for service processes.
25115 This is mainly intended to catch and kill processes that leak memory
25116 before they eat up everything.
25117 Defaults to @samp{256000000}.
25120 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
25121 Login user is internally used by login processes. This is the most
25122 untrusted user in Dovecot system. It shouldn't have access to anything
25124 Defaults to @samp{"dovenull"}.
25127 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
25128 Internal user is used by unprivileged processes. It should be
25129 separate from login user, so that login processes can't disturb other
25131 Defaults to @samp{"dovecot"}.
25134 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
25135 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
25136 Defaults to @samp{"required"}.
25139 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
25140 PEM encoded X.509 SSL/TLS certificate (public key).
25141 Defaults to @samp{"</etc/dovecot/default.pem"}.
25144 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
25145 PEM encoded SSL/TLS private key. The key is opened before
25146 dropping root privileges, so keep the key file unreadable by anyone but
25148 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
25151 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
25152 If key file is password protected, give the password here.
25153 Alternatively give it when starting dovecot with -p parameter. Since
25154 this file is often world-readable, you may want to place this setting
25155 instead to a different.
25156 Defaults to @samp{""}.
25159 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
25160 PEM encoded trusted certificate authority. Set this only if you
25161 intend to use @samp{ssl-verify-client-cert? #t}. The file should
25162 contain the CA certificate(s) followed by the matching
25163 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
25164 Defaults to @samp{""}.
25167 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
25168 Require that CRL check succeeds for client certificates.
25169 Defaults to @samp{#t}.
25172 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
25173 Request client to send a certificate. If you also want to require
25174 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
25175 Defaults to @samp{#f}.
25178 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
25179 Which field from certificate to use for username. commonName and
25180 x500UniqueIdentifier are the usual choices. You'll also need to set
25181 @samp{auth-ssl-username-from-cert? #t}.
25182 Defaults to @samp{"commonName"}.
25185 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
25186 Minimum SSL protocol version to accept.
25187 Defaults to @samp{"TLSv1"}.
25190 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
25191 SSL ciphers to use.
25192 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
25195 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
25196 SSL crypto device to use, for valid values run "openssl engine".
25197 Defaults to @samp{""}.
25200 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
25201 Address to use when sending rejection mails.
25202 %d expands to recipient domain.
25203 Defaults to @samp{"postmaster@@%d"}.
25206 @deftypevr {@code{dovecot-configuration} parameter} string hostname
25207 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
25208 and in LMTP replies. Default is the system's real hostname@@domain.
25209 Defaults to @samp{""}.
25212 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
25213 If user is over quota, return with temporary failure instead of
25215 Defaults to @samp{#f}.
25218 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
25219 Binary to use for sending mails.
25220 Defaults to @samp{"/usr/sbin/sendmail"}.
25223 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
25224 If non-empty, send mails via this SMTP host[:port] instead of
25226 Defaults to @samp{""}.
25229 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
25230 Subject: header to use for rejection mails. You can use the same
25231 variables as for @samp{rejection-reason} below.
25232 Defaults to @samp{"Rejected: %s"}.
25235 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
25236 Human readable error message for rejection mails. You can use
25249 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
25252 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
25253 Delimiter character between local-part and detail in email
25255 Defaults to @samp{"+"}.
25258 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
25259 Header where the original recipient address (SMTP's RCPT TO:
25260 address) is taken from if not available elsewhere. With dovecot-lda -a
25261 parameter overrides this. A commonly used header for this is
25263 Defaults to @samp{""}.
25266 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
25267 Should saving a mail to a nonexistent mailbox automatically create
25269 Defaults to @samp{#f}.
25272 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
25273 Should automatically created mailboxes be also automatically
25275 Defaults to @samp{#f}.
25278 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
25279 Maximum IMAP command line length. Some clients generate very long
25280 command lines with huge mailboxes, so you may need to raise this if you
25281 get "Too long argument" or "IMAP command line too large" errors
25283 Defaults to @samp{64000}.
25286 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
25287 IMAP logout format string:
25290 total number of bytes read from client
25292 total number of bytes sent to client.
25294 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
25295 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@}"}.
25298 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
25299 Override the IMAP CAPABILITY response. If the value begins with '+',
25300 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
25301 Defaults to @samp{""}.
25304 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
25305 How long to wait between "OK Still here" notifications when client
25307 Defaults to @samp{"2 mins"}.
25310 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
25311 ID field names and values to send to clients. Using * as the value
25312 makes Dovecot use the default value. The following fields have default
25313 values currently: name, version, os, os-version, support-url,
25315 Defaults to @samp{""}.
25318 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
25319 ID fields sent by client to log. * means everything.
25320 Defaults to @samp{""}.
25323 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
25324 Workarounds for various client bugs:
25327 @item delay-newmail
25328 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
25329 CHECK commands. Some clients ignore them otherwise, for example OSX
25330 Mail (<v2.1). Outlook Express breaks more badly though, without this it
25331 may show user "Message no longer in server" errors. Note that OE6
25332 still breaks even with this workaround if synchronization is set to
25335 @item tb-extra-mailbox-sep
25336 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
25337 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
25338 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
25340 @item tb-lsub-flags
25341 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
25342 This makes Thunderbird realize they aren't selectable and show them
25343 greyed out, instead of only later giving "not selectable" popup error.
25345 Defaults to @samp{()}.
25348 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
25349 Host allowed in URLAUTH URLs sent by client. "*" allows all.
25350 Defaults to @samp{""}.
25354 Whew! Lots of configuration options. The nice thing about it though is
25355 that Guix has a complete interface to Dovecot's configuration
25356 language. This allows not only a nice way to declare configurations,
25357 but also offers reflective capabilities as well: users can write code to
25358 inspect and transform configurations from within Scheme.
25360 However, it could be that you just want to get a @code{dovecot.conf} up
25361 and running. In that case, you can pass an
25362 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
25363 @code{dovecot-service}. As its name indicates, an opaque configuration
25364 does not have easy reflective capabilities.
25366 Available @code{opaque-dovecot-configuration} fields are:
25368 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
25369 The dovecot package.
25372 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
25373 The contents of the @code{dovecot.conf}, as a string.
25376 For example, if your @code{dovecot.conf} is just the empty string, you
25377 could instantiate a dovecot service like this:
25380 (dovecot-service #:config
25381 (opaque-dovecot-configuration
25385 @subsubheading OpenSMTPD Service
25387 @deffn {Scheme Variable} opensmtpd-service-type
25388 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
25389 service, whose value should be an @code{opensmtpd-configuration} object
25390 as in this example:
25393 (service opensmtpd-service-type
25394 (opensmtpd-configuration
25395 (config-file (local-file "./my-smtpd.conf"))))
25399 @deftp {Data Type} opensmtpd-configuration
25400 Data type representing the configuration of opensmtpd.
25403 @item @code{package} (default: @var{opensmtpd})
25404 Package object of the OpenSMTPD SMTP server.
25406 @item @code{config-file} (default: @code{%default-opensmtpd-config-file})
25407 File-like object of the OpenSMTPD configuration file to use. By default
25408 it listens on the loopback network interface, and allows for mail from
25409 users and daemons on the local machine, as well as permitting email to
25410 remote servers. Run @command{man smtpd.conf} for more information.
25412 @item @code{setgid-commands?} (default: @code{#t})
25413 Make the following commands setgid to @code{smtpq} so they can be
25414 executed: @command{smtpctl}, @command{sendmail}, @command{send-mail},
25415 @command{makemap}, @command{mailq}, and @command{newaliases}.
25416 @xref{Setuid Programs}, for more information on setgid programs.
25420 @subsubheading Exim Service
25422 @cindex mail transfer agent (MTA)
25423 @cindex MTA (mail transfer agent)
25426 @deffn {Scheme Variable} exim-service-type
25427 This is the type of the @uref{https://exim.org, Exim} mail transfer
25428 agent (MTA), whose value should be an @code{exim-configuration} object
25429 as in this example:
25432 (service exim-service-type
25433 (exim-configuration
25434 (config-file (local-file "./my-exim.conf"))))
25438 In order to use an @code{exim-service-type} service you must also have a
25439 @code{mail-aliases-service-type} service present in your
25440 @code{operating-system} (even if it has no aliases).
25442 @deftp {Data Type} exim-configuration
25443 Data type representing the configuration of exim.
25446 @item @code{package} (default: @var{exim})
25447 Package object of the Exim server.
25449 @item @code{config-file} (default: @code{#f})
25450 File-like object of the Exim configuration file to use. If its value is
25451 @code{#f} then use the default configuration file from the package
25452 provided in @code{package}. The resulting configuration file is loaded
25453 after setting the @code{exim_user} and @code{exim_group} configuration
25459 @subsubheading Getmail service
25464 @deffn {Scheme Variable} getmail-service-type
25465 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
25466 mail retriever, whose value should be an @code{getmail-configuration}.
25469 Available @code{getmail-configuration} fields are:
25471 @deftypevr {@code{getmail-configuration} parameter} symbol name
25472 A symbol to identify the getmail service.
25474 Defaults to @samp{"unset"}.
25478 @deftypevr {@code{getmail-configuration} parameter} package package
25479 The getmail package to use.
25483 @deftypevr {@code{getmail-configuration} parameter} string user
25484 The user to run getmail as.
25486 Defaults to @samp{"getmail"}.
25490 @deftypevr {@code{getmail-configuration} parameter} string group
25491 The group to run getmail as.
25493 Defaults to @samp{"getmail"}.
25497 @deftypevr {@code{getmail-configuration} parameter} string directory
25498 The getmail directory to use.
25500 Defaults to @samp{"/var/lib/getmail/default"}.
25504 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
25505 The getmail configuration file to use.
25507 Available @code{getmail-configuration-file} fields are:
25509 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
25510 What mail account to retrieve mail from, and how to access that account.
25512 Available @code{getmail-retriever-configuration} fields are:
25514 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
25515 The type of mail retriever to use. Valid values include @samp{passwd}
25518 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
25522 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
25523 Username to login to the mail server with.
25525 Defaults to @samp{unset}.
25529 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
25530 Username to login to the mail server with.
25532 Defaults to @samp{unset}.
25536 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
25537 Port number to connect to.
25539 Defaults to @samp{#f}.
25543 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
25544 Override fields from passwd.
25546 Defaults to @samp{""}.
25550 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
25551 Override fields from passwd.
25553 Defaults to @samp{()}.
25557 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
25558 PEM-formatted key file to use for the TLS negotiation.
25560 Defaults to @samp{""}.
25564 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
25565 PEM-formatted certificate file to use for the TLS negotiation.
25567 Defaults to @samp{""}.
25571 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
25572 CA certificates to use.
25574 Defaults to @samp{""}.
25578 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
25579 Extra retriever parameters.
25581 Defaults to @samp{()}.
25587 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
25588 What to do with retrieved messages.
25590 Available @code{getmail-destination-configuration} fields are:
25592 @deftypevr {@code{getmail-destination-configuration} parameter} string type
25593 The type of mail destination. Valid values include @samp{Maildir},
25594 @samp{Mboxrd} and @samp{MDA_external}.
25596 Defaults to @samp{unset}.
25600 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
25601 The path option for the mail destination. The behaviour depends on the
25604 Defaults to @samp{""}.
25608 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
25609 Extra destination parameters
25611 Defaults to @samp{()}.
25617 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
25620 Available @code{getmail-options-configuration} fields are:
25622 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
25623 If set to @samp{0}, getmail will only print warnings and errors. A
25624 value of @samp{1} means that messages will be printed about retrieving
25625 and deleting messages. If set to @samp{2}, getmail will print messages
25626 about each of its actions.
25628 Defaults to @samp{1}.
25632 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
25633 If true, getmail will retrieve all available messages. Otherwise it
25634 will only retrieve messages it hasn't seen previously.
25636 Defaults to @samp{#t}.
25640 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
25641 If set to true, messages will be deleted from the server after
25642 retrieving and successfully delivering them. Otherwise, messages will
25643 be left on the server.
25645 Defaults to @samp{#f}.
25649 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
25650 Getmail will delete messages this number of days after seeing them, if
25651 they have been delivered. This means messages will be left on the
25652 server this number of days after delivering them. A value of @samp{0}
25653 disabled this feature.
25655 Defaults to @samp{0}.
25659 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
25660 Delete messages larger than this of bytes after retrieving them, even if
25661 the delete and delete-after options are disabled. A value of @samp{0}
25662 disables this feature.
25664 Defaults to @samp{0}.
25668 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
25669 Retrieve messages totalling up to this number of bytes before closing
25670 the session with the server. A value of @samp{0} disables this feature.
25672 Defaults to @samp{0}.
25676 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
25677 Don't retrieve messages larger than this number of bytes. A value of
25678 @samp{0} disables this feature.
25680 Defaults to @samp{0}.
25684 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
25685 If true, getmail will add a Delivered-To header to messages.
25687 Defaults to @samp{#t}.
25691 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
25692 If set, getmail adds a Received header to the messages.
25694 Defaults to @samp{#t}.
25698 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
25699 Getmail will record a log of its actions to the named file. A value of
25700 @samp{""} disables this feature.
25702 Defaults to @samp{""}.
25706 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
25707 If true, getmail will record a log of its actions using the system
25710 Defaults to @samp{#f}.
25714 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
25715 If true, getmail will log information about messages not retrieved and
25716 the reason for not retrieving them, as well as starting and ending
25719 Defaults to @samp{#f}.
25723 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
25724 Extra options to include.
25726 Defaults to @samp{()}.
25734 @deftypevr {@code{getmail-configuration} parameter} list idle
25735 A list of mailboxes that getmail should wait on the server for new mail
25736 notifications. This depends on the server supporting the IDLE
25739 Defaults to @samp{()}.
25743 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
25744 Environment variables to set for getmail.
25746 Defaults to @samp{()}.
25750 @subsubheading Mail Aliases Service
25752 @cindex email aliases
25753 @cindex aliases, for email addresses
25755 @deffn {Scheme Variable} mail-aliases-service-type
25756 This is the type of the service which provides @code{/etc/aliases},
25757 specifying how to deliver mail to users on this system.
25760 (service mail-aliases-service-type
25761 '(("postmaster" "bob")
25762 ("bob" "bob@@example.com" "bob@@example2.com")))
25766 The configuration for a @code{mail-aliases-service-type} service is an
25767 association list denoting how to deliver mail that comes to this
25768 system. Each entry is of the form @code{(alias addresses ...)}, with
25769 @code{alias} specifying the local alias and @code{addresses} specifying
25770 where to deliver this user's mail.
25772 The aliases aren't required to exist as users on the local system. In
25773 the above example, there doesn't need to be a @code{postmaster} entry in
25774 the @code{operating-system}'s @code{user-accounts} in order to deliver
25775 the @code{postmaster} mail to @code{bob} (which subsequently would
25776 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
25778 @subsubheading GNU Mailutils IMAP4 Daemon
25779 @cindex GNU Mailutils IMAP4 Daemon
25781 @deffn {Scheme Variable} imap4d-service-type
25782 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
25783 mailutils, GNU Mailutils Manual}), whose value should be an
25784 @code{imap4d-configuration} object as in this example:
25787 (service imap4d-service-type
25788 (imap4d-configuration
25789 (config-file (local-file "imap4d.conf"))))
25793 @deftp {Data Type} imap4d-configuration
25794 Data type representing the configuration of @command{imap4d}.
25797 @item @code{package} (default: @code{mailutils})
25798 The package that provides @command{imap4d}.
25800 @item @code{config-file} (default: @code{%default-imap4d-config-file})
25801 File-like object of the configuration file to use, by default it will listen
25802 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
25803 Mailutils Manual}, for details.
25808 @subsubheading Radicale Service
25812 @deffn {Scheme Variable} radicale-service-type
25813 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
25814 server whose value should be a @code{radicale-configuration}.
25817 @deftp {Data Type} radicale-configuration
25818 Data type representing the configuration of @command{radicale}.
25821 @item @code{package} (default: @code{radicale})
25822 The package that provides @command{radicale}.
25824 @item @code{config-file} (default: @code{%default-radicale-config-file})
25825 File-like object of the configuration file to use, by default it will listen
25826 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
25827 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
25832 @node Messaging Services
25833 @subsection Messaging Services
25838 The @code{(gnu services messaging)} module provides Guix service
25839 definitions for messaging services. Currently it provides the following
25842 @subsubheading Prosody Service
25844 @deffn {Scheme Variable} prosody-service-type
25845 This is the type for the @uref{https://prosody.im, Prosody XMPP
25846 communication server}. Its value must be a @code{prosody-configuration}
25847 record as in this example:
25850 (service prosody-service-type
25851 (prosody-configuration
25852 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
25855 (int-component-configuration
25856 (hostname "conference.example.net")
25858 (mod-muc (mod-muc-configuration)))))
25861 (virtualhost-configuration
25862 (domain "example.net"))))))
25865 See below for details about @code{prosody-configuration}.
25869 By default, Prosody does not need much configuration. Only one
25870 @code{virtualhosts} field is needed: it specifies the domain you wish
25873 You can perform various sanity checks on the generated configuration
25874 with the @code{prosodyctl check} command.
25876 Prosodyctl will also help you to import certificates from the
25877 @code{letsencrypt} directory so that the @code{prosody} user can access
25878 them. See @url{https://prosody.im/doc/letsencrypt}.
25881 prosodyctl --root cert import /etc/letsencrypt/live
25884 The available configuration parameters follow. Each parameter
25885 definition is preceded by its type; for example, @samp{string-list foo}
25886 indicates that the @code{foo} parameter should be specified as a list of
25887 strings. Types starting with @code{maybe-} denote parameters that won't
25888 show up in @code{prosody.cfg.lua} when their value is left unspecified.
25890 There is also a way to specify the configuration as a string, if you
25891 have an old @code{prosody.cfg.lua} file that you want to port over from
25892 some other system; see the end for more details.
25894 The @code{file-object} type designates either a file-like object
25895 (@pxref{G-Expressions, file-like objects}) or a file name.
25897 @c The following documentation was initially generated by
25898 @c (generate-documentation) in (gnu services messaging). Manually maintained
25899 @c documentation is better, so we shouldn't hesitate to edit below as
25900 @c needed. However if the change you want to make to this documentation
25901 @c can be done in an automated way, it's probably easier to change
25902 @c (generate-documentation) than to make it below and have to deal with
25903 @c the churn as Prosody updates.
25905 Available @code{prosody-configuration} fields are:
25907 @deftypevr {@code{prosody-configuration} parameter} package prosody
25908 The Prosody package.
25911 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
25912 Location of the Prosody data storage directory. See
25913 @url{https://prosody.im/doc/configure}.
25914 Defaults to @samp{"/var/lib/prosody"}.
25917 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
25918 Additional plugin directories. They are searched in all the specified
25919 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
25920 Defaults to @samp{()}.
25923 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
25924 Every virtual host and component needs a certificate so that clients and
25925 servers can securely verify its identity. Prosody will automatically load
25926 certificates/keys from the directory specified here.
25927 Defaults to @samp{"/etc/prosody/certs"}.
25930 @deftypevr {@code{prosody-configuration} parameter} string-list admins
25931 This is a list of accounts that are admins for the server. Note that you
25932 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
25933 @url{https://prosody.im/doc/creating_accounts}.
25934 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
25935 Defaults to @samp{()}.
25938 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
25939 Enable use of libevent for better performance under high load. See
25940 @url{https://prosody.im/doc/libevent}.
25941 Defaults to @samp{#f}.
25944 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
25945 This is the list of modules Prosody will load on startup. It looks for
25946 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
25947 Documentation on modules can be found at:
25948 @url{https://prosody.im/doc/modules}.
25949 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
25952 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
25953 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
25954 should you want to disable them then add them to this list.
25955 Defaults to @samp{()}.
25958 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
25959 Path to a text file where the shared groups are defined. If this path is
25960 empty then @samp{mod_groups} does nothing. See
25961 @url{https://prosody.im/doc/modules/mod_groups}.
25962 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
25965 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
25966 Disable account creation by default, for security. See
25967 @url{https://prosody.im/doc/creating_accounts}.
25968 Defaults to @samp{#f}.
25971 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
25972 These are the SSL/TLS-related settings. Most of them are disabled so to
25973 use Prosody's defaults. If you do not completely understand these options, do
25974 not add them to your config, it is easy to lower the security of your server
25975 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
25977 Available @code{ssl-configuration} fields are:
25979 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
25980 This determines what handshake to use.
25983 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
25984 Path to your private key file.
25987 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
25988 Path to your certificate file.
25991 @deftypevr {@code{ssl-configuration} parameter} file-object capath
25992 Path to directory containing root certificates that you wish Prosody to
25993 trust when verifying the certificates of remote servers.
25994 Defaults to @samp{"/etc/ssl/certs"}.
25997 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
25998 Path to a file containing root certificates that you wish Prosody to trust.
25999 Similar to @code{capath} but with all certificates concatenated together.
26002 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
26003 A list of verification options (these mostly map to OpenSSL's
26004 @code{set_verify()} flags).
26007 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
26008 A list of general options relating to SSL/TLS@. These map to OpenSSL's
26009 @code{set_options()}. For a full list of options available in LuaSec, see the
26013 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
26014 How long a chain of certificate authorities to check when looking for a
26015 trusted root certificate.
26018 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
26019 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
26020 clients, and in what order.
26023 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
26024 A path to a file containing parameters for Diffie-Hellman key exchange. You
26025 can create such a file with:
26026 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
26029 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
26030 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
26031 @samp{"secp384r1"}.
26034 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
26035 A list of ``extra'' verification options.
26038 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
26039 Password for encrypted private keys.
26044 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
26045 Whether to force all client-to-server connections to be encrypted or not.
26046 See @url{https://prosody.im/doc/modules/mod_tls}.
26047 Defaults to @samp{#f}.
26050 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
26051 Set of mechanisms that will never be offered. See
26052 @url{https://prosody.im/doc/modules/mod_saslauth}.
26053 Defaults to @samp{("DIGEST-MD5")}.
26056 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
26057 Whether to force all server-to-server connections to be encrypted or not.
26058 See @url{https://prosody.im/doc/modules/mod_tls}.
26059 Defaults to @samp{#f}.
26062 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
26063 Whether to require encryption and certificate authentication. This
26064 provides ideal security, but requires servers you communicate with to support
26065 encryption AND present valid, trusted certificates. See
26066 @url{https://prosody.im/doc/s2s#security}.
26067 Defaults to @samp{#f}.
26070 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
26071 Many servers don't support encryption or have invalid or self-signed
26072 certificates. You can list domains here that will not be required to
26073 authenticate using certificates. They will be authenticated using DNS@. See
26074 @url{https://prosody.im/doc/s2s#security}.
26075 Defaults to @samp{()}.
26078 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
26079 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
26080 valid certificates for some domains by specifying a list here. See
26081 @url{https://prosody.im/doc/s2s#security}.
26082 Defaults to @samp{()}.
26085 @deftypevr {@code{prosody-configuration} parameter} string authentication
26086 Select the authentication backend to use. The default provider stores
26087 passwords in plaintext and uses Prosody's configured data storage to store the
26088 authentication data. If you do not trust your server please see
26089 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
26090 about using the hashed backend. See also
26091 @url{https://prosody.im/doc/authentication}
26092 Defaults to @samp{"internal_plain"}.
26095 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
26096 Set logging options. Advanced logging configuration is not yet supported
26097 by the Prosody service. See @url{https://prosody.im/doc/logging}.
26098 Defaults to @samp{"*syslog"}.
26101 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
26102 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
26103 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
26106 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
26107 Maximum allowed size of the HTTP body (in bytes).
26110 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
26111 Some modules expose their own URL in various ways. This URL is built
26112 from the protocol, host and port used. If Prosody sits behind a proxy, the
26113 public URL will be @code{http-external-url} instead. See
26114 @url{https://prosody.im/doc/http#external_url}.
26117 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
26118 A host in Prosody is a domain on which user accounts can be created. For
26119 example if you want your users to have addresses like
26120 @samp{"john.smith@@example.com"} then you need to add a host
26121 @samp{"example.com"}. All options in this list will apply only to this host.
26124 The name @emph{virtual} host is used in configuration to avoid confusion with
26125 the actual physical host that Prosody is installed on. A single Prosody
26126 instance can serve many domains, each one defined as a VirtualHost entry in
26127 Prosody's configuration. Conversely a server that hosts a single domain would
26128 have just one VirtualHost entry.
26130 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
26133 Available @code{virtualhost-configuration} fields are:
26135 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:
26136 @deftypevr {@code{virtualhost-configuration} parameter} string domain
26137 Domain you wish Prosody to serve.
26142 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
26143 Components are extra services on a server which are available to clients,
26144 usually on a subdomain of the main server (such as
26145 @samp{"mycomponent.example.com"}). Example components might be chatroom
26146 servers, user directories, or gateways to other protocols.
26148 Internal components are implemented with Prosody-specific plugins. To add an
26149 internal component, you simply fill the hostname field, and the plugin you wish
26150 to use for the component.
26152 See @url{https://prosody.im/doc/components}.
26153 Defaults to @samp{()}.
26155 Available @code{int-component-configuration} fields are:
26157 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:
26158 @deftypevr {@code{int-component-configuration} parameter} string hostname
26159 Hostname of the component.
26162 @deftypevr {@code{int-component-configuration} parameter} string plugin
26163 Plugin you wish to use for the component.
26166 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
26167 Multi-user chat (MUC) is Prosody's module for allowing you to create
26168 hosted chatrooms/conferences for XMPP users.
26170 General information on setting up and using multi-user chatrooms can be found
26171 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
26172 which you should read if you are new to XMPP chatrooms.
26174 See also @url{https://prosody.im/doc/modules/mod_muc}.
26176 Available @code{mod-muc-configuration} fields are:
26178 @deftypevr {@code{mod-muc-configuration} parameter} string name
26179 The name to return in service discovery responses.
26180 Defaults to @samp{"Prosody Chatrooms"}.
26183 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
26184 If @samp{#t}, this will only allow admins to create new chatrooms.
26185 Otherwise anyone can create a room. The value @samp{"local"} restricts room
26186 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
26187 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
26188 restricts to service administrators only.
26189 Defaults to @samp{#f}.
26192 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
26193 Maximum number of history messages that will be sent to the member that has
26194 just joined the room.
26195 Defaults to @samp{20}.
26202 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
26203 External components use XEP-0114, which most standalone components
26204 support. To add an external component, you simply fill the hostname field. See
26205 @url{https://prosody.im/doc/components}.
26206 Defaults to @samp{()}.
26208 Available @code{ext-component-configuration} fields are:
26210 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:
26211 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
26212 Password which the component will use to log in.
26215 @deftypevr {@code{ext-component-configuration} parameter} string hostname
26216 Hostname of the component.
26221 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
26222 Port(s) Prosody listens on for component connections.
26223 Defaults to @samp{(5347)}.
26226 @deftypevr {@code{prosody-configuration} parameter} string component-interface
26227 Interface Prosody listens on for component connections.
26228 Defaults to @samp{"127.0.0.1"}.
26231 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
26232 Raw content that will be added to the configuration file.
26235 It could be that you just want to get a @code{prosody.cfg.lua}
26236 up and running. In that case, you can pass an
26237 @code{opaque-prosody-configuration} record as the value of
26238 @code{prosody-service-type}. As its name indicates, an opaque configuration
26239 does not have easy reflective capabilities.
26240 Available @code{opaque-prosody-configuration} fields are:
26242 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
26243 The prosody package.
26246 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
26247 The contents of the @code{prosody.cfg.lua} to use.
26250 For example, if your @code{prosody.cfg.lua} is just the empty
26251 string, you could instantiate a prosody service like this:
26254 (service prosody-service-type
26255 (opaque-prosody-configuration
26256 (prosody.cfg.lua "")))
26259 @c end of Prosody auto-generated documentation
26261 @subsubheading BitlBee Service
26263 @cindex IRC (Internet Relay Chat)
26264 @cindex IRC gateway
26265 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
26266 interface to a variety of messaging protocols such as XMPP.
26268 @defvr {Scheme Variable} bitlbee-service-type
26269 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
26270 gateway daemon. Its value is a @code{bitlbee-configuration} (see
26273 To have BitlBee listen on port 6667 on localhost, add this line to your
26277 (service bitlbee-service-type)
26281 @deftp {Data Type} bitlbee-configuration
26282 This is the configuration for BitlBee, with the following fields:
26285 @item @code{interface} (default: @code{"127.0.0.1"})
26286 @itemx @code{port} (default: @code{6667})
26287 Listen on the network interface corresponding to the IP address
26288 specified in @var{interface}, on @var{port}.
26290 When @var{interface} is @code{127.0.0.1}, only local clients can
26291 connect; when it is @code{0.0.0.0}, connections can come from any
26292 networking interface.
26294 @item @code{bitlbee} (default: @code{bitlbee})
26295 The BitlBee package to use.
26297 @item @code{plugins} (default: @code{'()})
26298 List of plugin packages to use---e.g., @code{bitlbee-discord}.
26300 @item @code{extra-settings} (default: @code{""})
26301 Configuration snippet added as-is to the BitlBee configuration file.
26305 @subsubheading Quassel Service
26307 @cindex IRC (Internet Relay Chat)
26308 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
26309 meaning that one or more clients can attach to and detach from the
26312 @defvr {Scheme Variable} quassel-service-type
26313 This is the service type for the @url{https://quassel-irc.org/,Quassel}
26314 IRC backend daemon. Its value is a @code{quassel-configuration}
26318 @deftp {Data Type} quassel-configuration
26319 This is the configuration for Quassel, with the following fields:
26322 @item @code{quassel} (default: @code{quassel})
26323 The Quassel package to use.
26325 @item @code{interface} (default: @code{"::,0.0.0.0"})
26326 @item @code{port} (default: @code{4242})
26327 Listen on the network interface(s) corresponding to the IPv4 or IPv6
26328 interfaces specified in the comma delimited @var{interface}, on
26331 @item @code{loglevel} (default: @code{"Info"})
26332 The level of logging desired. Accepted values are Debug, Info, Warning
26337 @node Telephony Services
26338 @subsection Telephony Services
26340 @cindex telephony, services
26341 The @code{(gnu services telephony)} module contains Guix service
26342 definitions for telephony services. Currently it provides the following
26345 @subsubheading Jami
26347 @cindex jami, service
26349 This section describes how to configure a Jami server that can be used
26350 to host video (or audio) conferences, among other uses. The following
26351 example demonstrates how to specify Jami account archives (backups) to
26352 be provisioned automatically:
26355 (service jami-service-type
26356 (jami-configuration
26358 (list (jami-account
26359 (archive "/etc/jami/unencrypted-account-1.gz"))
26361 (archive "/etc/jami/unencrypted-account-2.gz"))))))
26364 When the accounts field is specified, the Jami account files of the
26365 service found under @file{/var/lib/jami} are recreated every time the
26368 Jami accounts and their corresponding backup archives can be generated
26369 using the @code{jami} or @code{jami-gnome} Jami clients. The accounts
26370 should not be password-protected, but it is wise to ensure their files
26371 are only readable by @samp{root}.
26373 The next example shows how to declare that only some contacts should be
26374 allowed to communicate with a given account:
26377 (service jami-service-type
26378 (jami-configuration
26380 (list (jami-account
26381 (archive "/etc/jami/unencrypted-account-1.gz")
26382 (peer-discovery? #t)
26383 (rendezvous-point? #t)
26385 '("1dbcb0f5f37324228235564b79f2b9737e9a008f"
26386 "2dbcb0f5f37324228235564b79f2b9737e9a008f")))))))
26389 In this mode, only the declared @code{allowed-contacts} can initiate
26390 communication with the Jami account. This can be used, for example,
26391 with rendezvous point accounts to create a private video conferencing
26394 To put the system administrator in full control of the conferences
26395 hosted on their system, the Jami service supports the following actions:
26398 # herd doc jami list-actions
26400 list-account-details
26401 list-banned-contacts
26410 The above actions aim to provide the most valuable actions for
26411 moderation purposes, not to cover the whole Jami API. Users wanting to
26412 interact with the Jami daemon from Guile may be interested in
26413 experimenting with the @code{(gnu build jami-service)} module, which
26414 powers the above Shepherd actions.
26416 @c TODO: This should be auto-generated from the doc already defined on
26417 @c the shepherd-actions themselves in (gnu services telephony).
26418 The @code{add-moderator} and @code{ban-contact} actions accept a contact
26419 @emph{fingerprint} (40 characters long hash) as first argument and an
26420 account fingerprint or username as second argument:
26423 # herd add-moderator jami 1dbcb0f5f37324228235564b79f2b9737e9a008f \
26424 f3345f2775ddfe07a4b0d95daea111d15fbc1199
26426 # herd list-moderators jami
26427 Moderators for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26428 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26432 In the case of @code{ban-contact}, the second username argument is
26433 optional; when omitted, the account is banned from all Jami accounts:
26436 # herd ban-contact jami 1dbcb0f5f37324228235564b79f2b9737e9a008f
26438 # herd list-banned-contacts jami
26439 Banned contacts for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26440 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26444 Banned contacts are also stripped from their moderation privileges.
26446 The @code{disable-account} action allows to completely disconnect an
26447 account from the network, making it unreachable, while
26448 @code{enable-account} does the inverse. They accept a single account
26449 username or fingerprint as first argument:
26452 # herd disable-account jami f3345f2775ddfe07a4b0d95daea111d15fbc1199
26454 # herd list-accounts jami
26455 The following Jami accounts are available:
26456 - f3345f2775ddfe07a4b0d95daea111d15fbc1199 (dummy) [disabled]
26460 The @code{list-account-details} action prints the detailed parameters of
26461 each accounts in the Recutils format, which means the @command{recsel}
26462 command can be used to select accounts of interest (@pxref{Selection
26463 Expressions,,,recutils, GNU recutils manual}). Note that period
26464 characters (@samp{.}) found in the account parameter keys are mapped to
26465 underscores (@samp{_}) in the output, to meet the requirements of the
26466 Recutils format. The following example shows how to print the account
26467 fingerprints for all accounts operating in the rendezvous point mode:
26470 # herd list-account-details jami | \
26471 recsel -p Account.username -e 'Account.rendezVous ~ "true"'
26472 Account_username: f3345f2775ddfe07a4b0d95daea111d15fbc1199
26475 The remaining actions should be self-explanatory.
26477 The complete set of available configuration options is detailed below.
26479 @c TODO: Ideally, the following fragments would be auto-generated at
26480 @c build time, so that they needn't be manually duplicated.
26481 @c Auto-generated via (configuration->documentation 'jami-configuration)
26482 @deftp {Data Type} jami-configuration
26483 Available @code{jami-configuration} fields are:
26486 @item @code{libjami} (default: @code{libjami}) (type: package)
26487 The Jami daemon package to use.
26489 @item @code{dbus} (default: @code{dbus-for-jami}) (type: package)
26490 The D-Bus package to use to start the required D-Bus session.
26492 @item @code{nss-certs} (default: @code{nss-certs}) (type: package)
26493 The nss-certs package to use to provide TLS certificates.
26495 @item @code{enable-logging?} (default: @code{#t}) (type: boolean)
26496 Whether to enable logging to syslog.
26498 @item @code{debug?} (default: @code{#f}) (type: boolean)
26499 Whether to enable debug level messages.
26501 @item @code{auto-answer?} (default: @code{#f}) (type: boolean)
26502 Whether to force automatic answer to incoming calls.
26504 @item @code{accounts} (type: maybe-jami-account-list)
26505 A list of Jami accounts to be (re-)provisioned every time the Jami
26506 daemon service starts. When providing this field, the account
26507 directories under @file{/var/lib/jami/} are recreated every time the
26508 service starts, ensuring a consistent state.
26514 @c Auto-generated via (configuration->documentation 'jami-account)
26515 @deftp {Data Type} jami-account
26516 Available @code{jami-account} fields are:
26519 @item @code{archive} (type: string-or-computed-file)
26520 The account archive (backup) file name of the account. This is used to
26521 provision the account when the service starts. The account archive
26522 should @emph{not} be encrypted. It is highly recommended to make it
26523 readable only to the @samp{root} user (i.e., not in the store), to guard
26524 against leaking the secret key material of the Jami account it contains.
26526 @item @code{allowed-contacts} (type: maybe-account-fingerprint-list)
26527 The list of allowed contacts for the account, entered as their 40
26528 characters long fingerprint. Messages or calls from accounts not in
26529 that list will be rejected. When left specified, the configuration of
26530 the account archive is used as-is with respect to contacts and public
26531 inbound calls/messaging allowance, which typically defaults to allow any
26532 contact to communicate with the account.
26534 @item @code{moderators} (type: maybe-account-fingerprint-list)
26535 The list of contacts that should have moderation privileges (to ban,
26536 mute, etc. other users) in rendezvous conferences, entered as their 40
26537 characters long fingerprint. When left unspecified, the configuration
26538 of the account archive is used as-is with respect to moderation, which
26539 typically defaults to allow anyone to moderate.
26541 @item @code{rendezvous-point?} (type: maybe-boolean)
26542 Whether the account should operate in the rendezvous mode. In this
26543 mode, all the incoming audio/video calls are mixed into a conference.
26544 When left unspecified, the value from the account archive prevails.
26546 @item @code{peer-discovery?} (type: maybe-boolean)
26547 Whether peer discovery should be enabled. Peer discovery is used to
26548 discover other OpenDHT nodes on the local network, which can be useful
26549 to maintain communication between devices on such network even when the
26550 connection to the the Internet has been lost. When left unspecified,
26551 the value from the account archive prevails.
26553 @item @code{bootstrap-hostnames} (type: maybe-string-list)
26554 A list of hostnames or IPs pointing to OpenDHT nodes, that should be
26555 used to initially join the OpenDHT network. When left unspecified, the
26556 value from the account archive prevails.
26558 @item @code{name-server-uri} (type: maybe-string)
26559 The URI of the name server to use, that can be used to retrieve the
26560 account fingerprint for a registered username.
26566 @subsubheading Mumble server
26570 @cindex VoIP server
26571 This section describes how to set up and run a
26572 @uref{https://mumble.info, Mumble} server (formerly known as Murmur).
26574 @deftp {Data Type} mumble-server-configuration
26575 The service type for the Mumble server. An example configuration can
26579 (service mumble-server-service-type
26580 (mumble-server-configuration
26582 "Welcome to this Mumble server running on Guix!")
26583 (cert-required? #t) ;disallow text password logins
26584 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
26585 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
26588 After reconfiguring your system, you can manually set the mumble-server
26590 password with the command that is printed during the activation phase.
26592 It is recommended to register a normal Mumble user account
26593 and grant it admin or moderator rights.
26594 You can use the @code{mumble} client to
26595 login as new normal user, register yourself, and log out.
26596 For the next step login with the name @code{SuperUser} use
26597 the @code{SuperUser} password that you set previously,
26598 and grant your newly registered mumble user administrator or moderator
26599 rights and create some channels.
26601 Available @code{mumble-server-configuration} fields are:
26604 @item @code{package} (default: @code{mumble})
26605 Package that contains @code{bin/mumble-server}.
26607 @item @code{user} (default: @code{"mumble-server"})
26608 User who will run the Mumble-Server server.
26610 @item @code{group} (default: @code{"mumble-server"})
26611 Group of the user who will run the mumble-server server.
26613 @item @code{port} (default: @code{64738})
26614 Port on which the server will listen.
26616 @item @code{welcome-text} (default: @code{""})
26617 Welcome text sent to clients when they connect.
26619 @item @code{server-password} (default: @code{""})
26620 Password the clients have to enter in order to connect.
26622 @item @code{max-users} (default: @code{100})
26623 Maximum of users that can be connected to the server at once.
26625 @item @code{max-user-bandwidth} (default: @code{#f})
26626 Maximum voice traffic a user can send per second.
26628 @item @code{database-file} (default: @code{"/var/lib/mumble-server/db.sqlite"})
26629 File name of the sqlite database.
26630 The service's user will become the owner of the directory.
26632 @item @code{log-file} (default: @code{"/var/log/mumble-server/mumble-server.log"})
26633 File name of the log file.
26634 The service's user will become the owner of the directory.
26636 @item @code{autoban-attempts} (default: @code{10})
26637 Maximum number of logins a user can make in @code{autoban-timeframe}
26638 without getting auto banned for @code{autoban-time}.
26640 @item @code{autoban-timeframe} (default: @code{120})
26641 Timeframe for autoban in seconds.
26643 @item @code{autoban-time} (default: @code{300})
26644 Amount of time in seconds for which a client gets banned
26645 when violating the autoban limits.
26647 @item @code{opus-threshold} (default: @code{100})
26648 Percentage of clients that need to support opus
26649 before switching over to opus audio codec.
26651 @item @code{channel-nesting-limit} (default: @code{10})
26652 How deep channels can be nested at maximum.
26654 @item @code{channelname-regex} (default: @code{#f})
26655 A string in form of a Qt regular expression that channel names must conform to.
26657 @item @code{username-regex} (default: @code{#f})
26658 A string in form of a Qt regular expression that user names must conform to.
26660 @item @code{text-message-length} (default: @code{5000})
26661 Maximum size in bytes that a user can send in one text chat message.
26663 @item @code{image-message-length} (default: @code{(* 128 1024)})
26664 Maximum size in bytes that a user can send in one image message.
26666 @item @code{cert-required?} (default: @code{#f})
26667 If it is set to @code{#t} clients that use weak password authentication
26668 will not be accepted. Users must have completed the certificate wizard to join.
26670 @item @code{remember-channel?} (default: @code{#f})
26671 Should mumble-server remember the last channel each user was in when
26672 they disconnected and put them into the remembered channel when they
26675 @item @code{allow-html?} (default: @code{#f})
26676 Should html be allowed in text messages, user comments, and channel descriptions.
26678 @item @code{allow-ping?} (default: @code{#f})
26679 Setting to true exposes the current user count, the maximum user count, and
26680 the server's maximum bandwidth per client to unauthenticated users. In the
26681 Mumble client, this information is shown in the Connect dialog.
26683 Disabling this setting will prevent public listing of the server.
26685 @item @code{bonjour?} (default: @code{#f})
26686 Should the server advertise itself in the local network through the bonjour protocol.
26688 @item @code{send-version?} (default: @code{#f})
26689 Should the mumble-server server version be exposed in ping requests.
26691 @item @code{log-days} (default: @code{31})
26692 Mumble also stores logs in the database, which are accessible via RPC.
26693 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
26694 or -1 to disable logging to the database.
26696 @item @code{obfuscate-ips?} (default: @code{#t})
26697 Should logged ips be obfuscated to protect the privacy of users.
26699 @item @code{ssl-cert} (default: @code{#f})
26700 File name of the SSL/TLS certificate used for encrypted connections.
26703 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
26705 @item @code{ssl-key} (default: @code{#f})
26706 Filepath to the ssl private key used for encrypted connections.
26708 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
26711 @item @code{ssl-dh-params} (default: @code{#f})
26712 File name of a PEM-encoded file with Diffie-Hellman parameters
26713 for the SSL/TLS encryption. Alternatively you set it to
26714 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
26715 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
26717 @item @code{ssl-ciphers} (default: @code{#f})
26718 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
26721 This option is specified using
26722 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
26723 OpenSSL cipher list notation}.
26725 It is recommended that you try your cipher string using
26726 'openssl ciphers <string>' before setting it here, to get a feel for
26727 which cipher suites you will get.
26728 After setting this option, it is recommend that you inspect your Mumble
26729 server log to ensure that Mumble is using the cipher suites that you
26733 Changing this option may impact the backwards compatibility of your
26734 Mumble-Server server, and can remove the ability for older Mumble clients to be able to connect to it.
26737 @item @code{public-registration} (default: @code{#f})
26738 Must be a @code{<mumble-server-public-registration-configuration>}
26739 record or @code{#f}.
26741 You can optionally register your server in the public server list that the
26742 @code{mumble} client shows on startup.
26743 You cannot register your server if you have set a @code{server-password},
26744 or set @code{allow-ping} to @code{#f}.
26746 It might take a few hours until it shows up in the public list.
26748 @item @code{file} (default: @code{#f})
26749 Optional alternative override for this configuration.
26753 @deftp {Data Type} mumble-server-public-registration-configuration
26754 Configuration for public registration of a mumble-server service.
26758 This is a display name for your server. Not to be confused with the hostname.
26760 @item @code{password}
26761 A password to identify your registration.
26762 Subsequent updates will need the same password. Don't lose your password.
26765 This should be a @code{http://} or @code{https://} link to your web
26768 @item @code{hostname} (default: @code{#f})
26769 By default your server will be listed by its IP address.
26770 If it is set your server will be linked by this host name instead.
26774 @quotation Deprecation notice
26775 Due to historical reasons, all of the above @code{mumble-server-}
26776 procedures are also exported with the @code{murmur-} prefix.
26777 It is recommended that you switch to using @code{mumble-server-}
26781 @node File-Sharing Services
26782 @subsection File-Sharing Services
26784 The @code{(gnu services file-sharing)} module provides services that
26785 assist with transferring files over peer-to-peer file-sharing networks.
26787 @subsubheading Transmission Daemon Service
26789 @uref{https://transmissionbt.com/, Transmission} is a flexible
26790 BitTorrent client that offers a variety of graphical and command-line
26791 interfaces. A @code{transmission-daemon-service-type} service provides
26792 Transmission's headless variant, @command{transmission-daemon}, as a
26793 system service, allowing users to share files via BitTorrent even when
26794 they are not logged in.
26796 @deffn {Scheme Variable} transmission-daemon-service-type
26797 The service type for the Transmission Daemon BitTorrent client. Its
26798 value must be a @code{transmission-daemon-configuration} object as in
26802 (service transmission-daemon-service-type
26803 (transmission-daemon-configuration
26804 ;; Restrict access to the RPC ("control") interface
26805 (rpc-authentication-required? #t)
26806 (rpc-username "transmission")
26808 (transmission-password-hash
26809 "transmission" ; desired password
26810 "uKd1uMs9")) ; arbitrary salt value
26812 ;; Accept requests from this and other hosts on the
26814 (rpc-whitelist-enabled? #t)
26815 (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
26817 ;; Limit bandwidth use during work hours
26818 (alt-speed-down (* 1024 2)) ; 2 MB/s
26819 (alt-speed-up 512) ; 512 kB/s
26821 (alt-speed-time-enabled? #t)
26822 (alt-speed-time-day 'weekdays)
26823 (alt-speed-time-begin
26824 (+ (* 60 8) 30)) ; 8:30 am
26825 (alt-speed-time-end
26826 (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
26830 Once the service is started, users can interact with the daemon through
26831 its Web interface (at @code{http://localhost:9091/}) or by using the
26832 @command{transmission-remote} command-line tool, available in the
26833 @code{transmission} package. (Emacs users may want to also consider the
26834 @code{emacs-transmission} package.) Both communicate with the daemon
26835 through its remote procedure call (RPC) interface, which by default is
26836 available to all users on the system; you may wish to change this by
26837 assigning values to the @code{rpc-authentication-required?},
26838 @code{rpc-username} and @code{rpc-password} settings, as shown in the
26839 example above and documented further below.
26841 The value for @code{rpc-password} must be a password hash of the type
26842 generated and used by Transmission clients. This can be copied verbatim
26843 from an existing @file{settings.json} file, if another Transmission
26844 client is already being used. Otherwise, the
26845 @code{transmission-password-hash} and @code{transmission-random-salt}
26846 procedures provided by this module can be used to obtain a suitable hash
26849 @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
26850 Returns a string containing the result of hashing @var{password}
26851 together with @var{salt}, in the format recognized by Transmission
26852 clients for their @code{rpc-password} configuration setting.
26854 @var{salt} must be an eight-character string. The
26855 @code{transmission-random-salt} procedure can be used to generate a
26856 suitable salt value at random.
26859 @deffn {Scheme Procedure} transmission-random-salt
26860 Returns a string containing a random, eight-character salt value of the
26861 type generated and used by Transmission clients, suitable for passing to
26862 the @code{transmission-password-hash} procedure.
26865 These procedures are accessible from within a Guile REPL started with
26866 the @command{guix repl} command (@pxref{Invoking guix repl}). This is
26867 useful for obtaining a random salt value to provide as the second
26868 parameter to `transmission-password-hash`, as in this example session:
26872 scheme@@(guix-user)> ,use (gnu services file-sharing)
26873 scheme@@(guix-user)> (transmission-random-salt)
26877 Alternatively, a complete password hash can generated in a single step:
26880 scheme@@(guix-user)> (transmission-password-hash "transmission"
26881 (transmission-random-salt))
26882 $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
26885 The resulting string can be used as-is for the value of
26886 @code{rpc-password}, allowing the password to be kept hidden even in the
26887 operating-system configuration.
26889 Torrent files downloaded by the daemon are directly accessible only to
26890 users in the ``transmission'' user group, who receive read-only access
26891 to the directory specified by the @code{download-dir} configuration
26892 setting (and also the directory specified by @code{incomplete-dir}, if
26893 @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
26894 moved to another directory or deleted altogether using
26895 @command{transmission-remote} with its @code{--move} and
26896 @code{--remove-and-delete} options.
26898 If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
26899 the ``transmission'' group are able also to place @file{.torrent} files
26900 in the directory specified by @code{watch-dir} to have the corresponding
26901 torrents added by the daemon. (The @code{trash-original-torrent-files?}
26902 setting controls whether the daemon deletes these files after processing
26905 Some of the daemon's configuration settings can be changed temporarily
26906 by @command{transmission-remote} and similar tools. To undo these
26907 changes, use the service's @code{reload} action to have the daemon
26908 reload its settings from disk:
26911 # herd reload transmission-daemon
26914 The full set of available configuration settings is defined by the
26915 @code{transmission-daemon-configuration} data type.
26917 @deftp {Data Type} transmission-daemon-configuration
26918 The data type representing configuration settings for Transmission
26919 Daemon. These correspond directly to the settings recognized by
26920 Transmission clients in their @file{settings.json} file.
26923 @c The following documentation was initially generated by
26924 @c (generate-transmission-daemon-documentation) in (gnu services
26925 @c file-sharing). Manually maintained documentation is better, so we
26926 @c shouldn't hesitate to edit below as needed. However if the change
26927 @c you want to make to this documentation can be done in an automated
26928 @c way, it's probably easier to change (generate-documentation) than to
26929 @c make it below and have to deal with the churn as Transmission Daemon
26932 @c %start of fragment
26934 Available @code{transmission-daemon-configuration} fields are:
26936 @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
26937 The Transmission package to use.
26941 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
26942 The period, in seconds, to wait when stopping the service for
26943 @command{transmission-daemon} to exit before killing its process. This
26944 allows the daemon time to complete its housekeeping and send a final
26945 update to trackers as it shuts down. On slow hosts, or hosts with a
26946 slow network connection, this value may need to be increased.
26948 Defaults to @samp{10}.
26952 @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
26953 The directory to which torrent files are downloaded.
26955 Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
26959 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
26960 If @code{#t}, files will be held in @code{incomplete-dir} while their
26961 torrent is being downloaded, then moved to @code{download-dir} once the
26962 torrent is complete. Otherwise, files for all torrents (including those
26963 still being downloaded) will be placed in @code{download-dir}.
26965 Defaults to @samp{#f}.
26969 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
26970 The directory in which files from incompletely downloaded torrents will
26971 be held when @code{incomplete-dir-enabled?} is @code{#t}.
26973 Defaults to @samp{disabled}.
26977 @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
26978 The file mode creation mask used for downloaded files. (See the
26979 @command{umask} man page for more information.)
26981 Defaults to @samp{18}.
26985 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
26986 When @code{#t}, ``.part'' is appended to the name of partially
26989 Defaults to @samp{#t}.
26993 @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
26994 The mode by which space should be preallocated for downloaded files, one
26995 of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
26996 Specifying @code{full} will minimize disk fragmentation at a cost to
26997 file-creation speed.
26999 Defaults to @samp{fast}.
27003 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
27004 If @code{#t}, the directory specified by @code{watch-dir} will be
27005 watched for new @file{.torrent} files and the torrents they describe
27006 added automatically (and the original files removed, if
27007 @code{trash-original-torrent-files?} is @code{#t}).
27009 Defaults to @samp{#f}.
27013 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
27014 The directory to be watched for @file{.torrent} files indicating new
27015 torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
27017 Defaults to @samp{disabled}.
27021 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
27022 When @code{#t}, @file{.torrent} files will be deleted from the watch
27023 directory once their torrent has been added (see
27024 @code{watch-directory-enabled?}).
27026 Defaults to @samp{#f}.
27030 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
27031 When @code{#t}, the daemon's download speed will be limited to the rate
27032 specified by @code{speed-limit-down}.
27034 Defaults to @samp{#f}.
27038 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
27039 The default global-maximum download speed, in kilobytes per second.
27041 Defaults to @samp{100}.
27045 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
27046 When @code{#t}, the daemon's upload speed will be limited to the rate
27047 specified by @code{speed-limit-up}.
27049 Defaults to @samp{#f}.
27053 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
27054 The default global-maximum upload speed, in kilobytes per second.
27056 Defaults to @samp{100}.
27060 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
27061 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
27062 @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
27063 @code{speed-limit-up}, if they are enabled) to constrain the daemon's
27064 bandwidth usage. This can be scheduled to occur automatically at
27065 certain times during the week; see @code{alt-speed-time-enabled?}.
27067 Defaults to @samp{#f}.
27071 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
27072 The alternate global-maximum download speed, in kilobytes per second.
27074 Defaults to @samp{50}.
27078 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
27079 The alternate global-maximum upload speed, in kilobytes per second.
27081 Defaults to @samp{50}.
27085 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
27086 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
27087 @code{alt-speed-up} will be enabled automatically during the periods
27088 specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
27089 @code{alt-time-speed-end}.
27091 Defaults to @samp{#f}.
27095 @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
27096 The days of the week on which the alternate-speed schedule should be
27097 used, specified either as a list of days (@code{sunday}, @code{monday},
27098 and so on) or using one of the symbols @code{weekdays}, @code{weekends}
27101 Defaults to @samp{all}.
27105 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
27106 The time of day at which to enable the alternate speed limits, expressed
27107 as a number of minutes since midnight.
27109 Defaults to @samp{540}.
27113 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
27114 The time of day at which to disable the alternate speed limits,
27115 expressed as a number of minutes since midnight.
27117 Defaults to @samp{1020}.
27121 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
27122 The IP address at which to listen for peer connections, or ``0.0.0.0''
27123 to listen at all available IP addresses.
27125 Defaults to @samp{"0.0.0.0"}.
27129 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
27130 The IPv6 address at which to listen for peer connections, or ``::'' to
27131 listen at all available IPv6 addresses.
27133 Defaults to @samp{"::"}.
27137 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
27138 If @code{#t}, when the daemon starts it will select a port at random on
27139 which to listen for peer connections, from the range specified
27140 (inclusively) by @code{peer-port-random-low} and
27141 @code{peer-port-random-high}. Otherwise, it listens on the port
27142 specified by @code{peer-port}.
27144 Defaults to @samp{#f}.
27148 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
27149 The lowest selectable port number when @code{peer-port-random-on-start?}
27152 Defaults to @samp{49152}.
27156 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
27157 The highest selectable port number when @code{peer-port-random-on-start}
27160 Defaults to @samp{65535}.
27164 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
27165 The port on which to listen for peer connections when
27166 @code{peer-port-random-on-start?} is @code{#f}.
27168 Defaults to @samp{51413}.
27172 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
27173 If @code{#t}, the daemon will attempt to configure port-forwarding on an
27174 upstream gateway automatically using @acronym{UPnP} and
27177 Defaults to @samp{#t}.
27181 @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
27182 The encryption preference for peer connections, one of
27183 @code{prefer-unencrypted-connections},
27184 @code{prefer-encrypted-connections} or
27185 @code{require-encrypted-connections}.
27187 Defaults to @samp{prefer-encrypted-connections}.
27191 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
27192 The TCP congestion-control algorithm to use for peer connections,
27193 specified using a string recognized by the operating system in calls to
27194 @code{setsockopt}. When left unspecified, the operating-system default
27197 Note that on GNU/Linux systems, the kernel must be configured to allow
27198 processes to use a congestion-control algorithm not in the default set;
27199 otherwise, it will deny these requests with ``Operation not permitted''.
27200 To see which algorithms are available on your system and which are
27201 currently permitted for use, look at the contents of the files
27202 @file{tcp_available_congestion_control} and
27203 @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
27206 As an example, to have Transmission Daemon use
27207 @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
27208 congestion-control algorithm}, you'll need to modify your kernel
27209 configuration to build in support for the algorithm, then update your
27210 operating-system configuration to allow its use by adding a
27211 @code{sysctl-service-type} service (or updating the existing one's
27212 configuration) with lines like the following:
27215 (service sysctl-service-type
27216 (sysctl-configuration
27218 ("net.ipv4.tcp_allowed_congestion_control" .
27219 "reno cubic lp"))))
27222 The Transmission Daemon configuration can then be updated with
27225 (peer-congestion-algorithm "lp")
27228 and the system reconfigured to have the changes take effect.
27230 Defaults to @samp{disabled}.
27234 @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
27235 The type of service to request in outgoing @acronym{TCP} packets, one of
27236 @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
27237 @code{reliability}.
27239 Defaults to @samp{default}.
27243 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
27244 The global limit on the number of connected peers.
27246 Defaults to @samp{200}.
27250 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
27251 The per-torrent limit on the number of connected peers.
27253 Defaults to @samp{50}.
27257 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
27258 The maximum number of peers to which the daemon will upload data
27259 simultaneously for each torrent.
27261 Defaults to @samp{14}.
27265 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
27266 The maximum lifespan, in hours, of the peer ID associated with each
27267 public torrent before it is regenerated.
27269 Defaults to @samp{6}.
27273 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
27274 When @code{#t}, the daemon will ignore peers mentioned in the blocklist
27275 it has most recently downloaded from @code{blocklist-url}.
27277 Defaults to @samp{#f}.
27281 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
27282 The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
27283 @file{.dat} format) to be periodically downloaded and applied when
27284 @code{blocklist-enabled?} is @code{#t}.
27286 Defaults to @samp{disabled}.
27290 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
27291 If @code{#t}, the daemon will be limited to downloading at most
27292 @code{download-queue-size} non-stalled torrents simultaneously.
27294 Defaults to @samp{#t}.
27298 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
27299 The size of the daemon's download queue, which limits the number of
27300 non-stalled torrents it will download at any one time when
27301 @code{download-queue-enabled?} is @code{#t}.
27303 Defaults to @samp{5}.
27307 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
27308 If @code{#t}, the daemon will be limited to seeding at most
27309 @code{seed-queue-size} non-stalled torrents simultaneously.
27311 Defaults to @samp{#f}.
27315 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
27316 The size of the daemon's seed queue, which limits the number of
27317 non-stalled torrents it will seed at any one time when
27318 @code{seed-queue-enabled?} is @code{#t}.
27320 Defaults to @samp{10}.
27324 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
27325 When @code{#t}, the daemon will consider torrents for which it has not
27326 shared data in the past @code{queue-stalled-minutes} minutes to be
27327 stalled and not count them against its @code{download-queue-size} and
27328 @code{seed-queue-size} limits.
27330 Defaults to @samp{#t}.
27334 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
27335 The maximum period, in minutes, a torrent may be idle before it is
27336 considered to be stalled, when @code{queue-stalled-enabled?} is
27339 Defaults to @samp{30}.
27343 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
27344 When @code{#t}, a torrent being seeded will automatically be paused once
27345 it reaches the ratio specified by @code{ratio-limit}.
27347 Defaults to @samp{#f}.
27351 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
27352 The ratio at which a torrent being seeded will be paused, when
27353 @code{ratio-limit-enabled?} is @code{#t}.
27355 Defaults to @samp{2.0}.
27359 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
27360 When @code{#t}, a torrent being seeded will automatically be paused once
27361 it has been idle for @code{idle-seeding-limit} minutes.
27363 Defaults to @samp{#f}.
27367 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
27368 The maximum period, in minutes, a torrent being seeded may be idle
27369 before it is paused, when @code{idle-seeding-limit-enabled?} is
27372 Defaults to @samp{30}.
27376 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
27377 Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
27378 hash table (@acronym{DHT}) protocol}, which supports the use of
27379 trackerless torrents.
27381 Defaults to @samp{#t}.
27385 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
27386 Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
27387 peer discovery} (@acronym{LPD}), which allows the discovery of peers on
27388 the local network and may reduce the amount of data sent over the public
27391 Defaults to @samp{#f}.
27395 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
27396 Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
27397 (@acronym{PEX}), which reduces the daemon's reliance on external
27398 trackers and may improve its performance.
27400 Defaults to @samp{#t}.
27404 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
27405 Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
27406 transport protocol} (@acronym{uTP}), which aims to reduce the impact of
27407 BitTorrent traffic on other users of the local network while maintaining
27408 full utilization of the available bandwidth.
27410 Defaults to @samp{#t}.
27414 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
27415 If @code{#t}, enable the remote procedure call (@acronym{RPC})
27416 interface, which allows remote control of the daemon via its Web
27417 interface, the @command{transmission-remote} command-line client, and
27420 Defaults to @samp{#t}.
27424 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
27425 The IP address at which to listen for @acronym{RPC} connections, or
27426 ``0.0.0.0'' to listen at all available IP addresses.
27428 Defaults to @samp{"0.0.0.0"}.
27432 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
27433 The port on which to listen for @acronym{RPC} connections.
27435 Defaults to @samp{9091}.
27439 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
27440 The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
27442 Defaults to @samp{"/transmission/"}.
27446 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
27447 When @code{#t}, clients must authenticate (see @code{rpc-username} and
27448 @code{rpc-password}) when using the @acronym{RPC} interface. Note this
27449 has the side effect of disabling host-name whitelisting (see
27450 @code{rpc-host-whitelist-enabled?}.
27452 Defaults to @samp{#f}.
27456 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
27457 The username required by clients to access the @acronym{RPC} interface
27458 when @code{rpc-authentication-required?} is @code{#t}.
27460 Defaults to @samp{disabled}.
27464 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
27465 The password required by clients to access the @acronym{RPC} interface
27466 when @code{rpc-authentication-required?} is @code{#t}. This must be
27467 specified using a password hash in the format recognized by Transmission
27468 clients, either copied from an existing @file{settings.json} file or
27469 generated using the @code{transmission-password-hash} procedure.
27471 Defaults to @samp{disabled}.
27475 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
27476 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27477 originate from an address specified in @code{rpc-whitelist}.
27479 Defaults to @samp{#t}.
27483 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
27484 The list of IP and IPv6 addresses from which @acronym{RPC} requests will
27485 be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
27486 may be specified using @samp{*}.
27488 Defaults to @samp{("127.0.0.1" "::1")}.
27492 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
27493 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27494 are addressed to a host named in @code{rpc-host-whitelist}. Note that
27495 requests to ``localhost'' or ``localhost.'', or to a numeric address,
27496 are always accepted regardless of these settings.
27498 Note also this functionality is disabled when
27499 @code{rpc-authentication-required?} is @code{#t}.
27501 Defaults to @samp{#t}.
27505 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
27506 The list of host names recognized by the @acronym{RPC} server when
27507 @code{rpc-host-whitelist-enabled?} is @code{#t}.
27509 Defaults to @samp{()}.
27513 @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
27514 The minimum severity level of messages to be logged (to
27515 @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
27516 logging), @code{error}, @code{info} and @code{debug}.
27518 Defaults to @samp{info}.
27522 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
27523 When @code{#t}, torrents are started as soon as they are added;
27524 otherwise, they are added in ``paused'' state.
27526 Defaults to @samp{#t}.
27530 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
27531 When @code{#t}, the script specified by
27532 @code{script-torrent-done-filename} will be invoked each time a torrent
27535 Defaults to @samp{#f}.
27539 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
27540 A file name or file-like object specifying a script to run each time a
27541 torrent completes, when @code{script-torrent-done-enabled?} is
27544 Defaults to @samp{disabled}.
27548 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
27549 When @code{#t}, the daemon will scrape trackers for a torrent even when
27550 the torrent is paused.
27552 Defaults to @samp{#t}.
27556 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
27557 The amount of memory, in megabytes, to allocate for the daemon's
27558 in-memory cache. A larger value may increase performance by reducing
27559 the frequency of disk I/O.
27561 Defaults to @samp{4}.
27565 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
27566 When @code{#t}, the daemon will try to improve I/O performance by
27567 hinting to the operating system which data is likely to be read next
27568 from disk to satisfy requests from peers.
27570 Defaults to @samp{#t}.
27575 @c %end of fragment
27579 @node Monitoring Services
27580 @subsection Monitoring Services
27582 @subsubheading Tailon Service
27584 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
27585 viewing and searching log files.
27587 The following example will configure the service with default values.
27588 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
27591 (service tailon-service-type)
27594 The following example customises more of the Tailon configuration,
27595 adding @command{sed} to the list of allowed commands.
27598 (service tailon-service-type
27599 (tailon-configuration
27601 (tailon-configuration-file
27602 (allowed-commands '("tail" "grep" "awk" "sed"))))))
27606 @deftp {Data Type} tailon-configuration
27607 Data type representing the configuration of Tailon.
27608 This type has the following parameters:
27611 @item @code{config-file} (default: @code{(tailon-configuration-file)})
27612 The configuration file to use for Tailon. This can be set to a
27613 @dfn{tailon-configuration-file} record value, or any gexp
27614 (@pxref{G-Expressions}).
27616 For example, to instead use a local file, the @code{local-file} function
27620 (service tailon-service-type
27621 (tailon-configuration
27622 (config-file (local-file "./my-tailon.conf"))))
27625 @item @code{package} (default: @code{tailon})
27626 The tailon package to use.
27631 @deftp {Data Type} tailon-configuration-file
27632 Data type representing the configuration options for Tailon.
27633 This type has the following parameters:
27636 @item @code{files} (default: @code{(list "/var/log")})
27637 List of files to display. The list can include strings for a single file
27638 or directory, or a list, where the first item is the name of a
27639 subsection, and the remaining items are the files or directories in that
27642 @item @code{bind} (default: @code{"localhost:8080"})
27643 Address and port to which Tailon should bind on.
27645 @item @code{relative-root} (default: @code{#f})
27646 URL path to use for Tailon, set to @code{#f} to not use a path.
27648 @item @code{allow-transfers?} (default: @code{#t})
27649 Allow downloading the log files in the web interface.
27651 @item @code{follow-names?} (default: @code{#t})
27652 Allow tailing of not-yet existent files.
27654 @item @code{tail-lines} (default: @code{200})
27655 Number of lines to read initially from each file.
27657 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
27658 Commands to allow running. By default, @code{sed} is disabled.
27660 @item @code{debug?} (default: @code{#f})
27661 Set @code{debug?} to @code{#t} to show debug messages.
27663 @item @code{wrap-lines} (default: @code{#t})
27664 Initial line wrapping state in the web interface. Set to @code{#t} to
27665 initially wrap lines (the default), or to @code{#f} to initially not
27668 @item @code{http-auth} (default: @code{#f})
27669 HTTP authentication type to use. Set to @code{#f} to disable
27670 authentication (the default). Supported values are @code{"digest"} or
27673 @item @code{users} (default: @code{#f})
27674 If HTTP authentication is enabled (see @code{http-auth}), access will be
27675 restricted to the credentials provided here. To configure users, use a
27676 list of pairs, where the first element of the pair is the username, and
27677 the 2nd element of the pair is the password.
27680 (tailon-configuration-file
27681 (http-auth "basic")
27682 (users '(("user1" . "password1")
27683 ("user2" . "password2"))))
27690 @subsubheading Darkstat Service
27692 Darkstat is a packet sniffer that captures network traffic, calculates
27693 statistics about usage, and serves reports over HTTP.
27695 @defvar {Scheme Variable} darkstat-service-type
27696 This is the service type for the
27697 @uref{https://unix4lyfe.org/darkstat/, darkstat}
27698 service, its value must be a @code{darkstat-configuration} record as in
27702 (service darkstat-service-type
27703 (darkstat-configuration
27704 (interface "eno1")))
27708 @deftp {Data Type} darkstat-configuration
27709 Data type representing the configuration of @command{darkstat}.
27712 @item @code{package} (default: @code{darkstat})
27713 The darkstat package to use.
27715 @item @code{interface}
27716 Capture traffic on the specified network interface.
27718 @item @code{port} (default: @code{"667"})
27719 Bind the web interface to the specified port.
27721 @item @code{bind-address} (default: @code{"127.0.0.1"})
27722 Bind the web interface to the specified address.
27724 @item @code{base} (default: @code{"/"})
27725 Specify the path of the base URL@. This can be useful if
27726 @command{darkstat} is accessed via a reverse proxy.
27731 @anchor{prometheus-node-exporter}
27732 @subsubheading Prometheus Node Exporter Service
27733 @cindex prometheus-node-exporter
27735 The Prometheus ``node exporter'' makes hardware and operating system statistics
27736 provided by the Linux kernel available for the Prometheus monitoring system.
27737 This service should be deployed on all physical nodes and virtual machines,
27738 where monitoring these statistics is desirable.
27740 @defvar {Scheme variable} prometheus-node-exporter-service-type
27741 This is the service type for the
27742 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
27743 service, its value must be a @code{prometheus-node-exporter-configuration}.
27746 (service prometheus-node-exporter-service-type)
27750 @deftp {Data Type} prometheus-node-exporter-configuration
27751 Data type representing the configuration of @command{node_exporter}.
27754 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
27755 The prometheus-node-exporter package to use.
27757 @item @code{web-listen-address} (default: @code{":9100"})
27758 Bind the web interface to the specified address.
27760 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
27761 This directory can be used to export metrics specific to this machine.
27762 Files containing metrics in the text format, with the filename ending in
27763 @code{.prom} should be placed in this directory.
27765 @item @code{extra-options} (default: @code{'()})
27766 Extra options to pass to the Prometheus node exporter.
27771 @subsubheading Zabbix server
27772 @cindex zabbix zabbix-server
27773 Zabbix is a high performance monitoring system that can collect data from a
27774 variety of sources and provide the results in a web-based interface. Alerting
27775 and reporting is built-in, as well as @dfn{templates} for common operating
27776 system metrics such as network utilization, CPU load, and disk space consumption.
27778 This service provides the central Zabbix monitoring service; you also need
27779 @ref{zabbix-front-end,@code{zabbix-front-end-service-type}} to configure Zabbix
27780 and display results, and optionally @ref{zabbix-agent,
27781 @code{zabbix-agent-service-type}} on machines that should be monitored (other
27782 data sources are supported, such as @ref{prometheus-node-exporter,
27783 Prometheus Node Exporter}).
27785 @defvar {Scheme variable} zabbix-server-service-type
27786 This is the service type for the Zabbix server service. Its value must be a
27787 @code{zabbix-server-configuration} record, shown below.
27790 @c %start of fragment
27792 @deftp {Data Type} zabbix-server-configuration
27793 Available @code{zabbix-server-configuration} fields are:
27796 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27797 The zabbix-server package.
27799 @item @code{user} (default: @code{"zabbix"}) (type: string)
27800 User who will run the Zabbix server.
27802 @item @code{group} (default: @code{"zabbix"}) (type: group)
27803 Group who will run the Zabbix server.
27805 @item @code{db-host} (default: @code{"127.0.0.1"}) (type: string)
27806 Database host name.
27808 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27811 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27814 @item @code{db-password} (default: @code{""}) (type: string)
27815 Database password. Please, use @code{include-files} with
27816 @code{DBPassword=SECRET} inside a specified file instead.
27818 @item @code{db-port} (default: @code{5432}) (type: number)
27821 @item @code{log-type} (default: @code{""}) (type: string)
27822 Specifies where log messages are written to:
27826 @item @code{system} - syslog.
27828 @item @code{file} - file specified with @code{log-file} parameter.
27830 @item @code{console} - standard output.
27834 @item @code{log-file} (default: @code{"/var/log/zabbix/server.log"}) (type: string)
27835 Log file name for @code{log-type} @code{file} parameter.
27837 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_server.pid"}) (type: string)
27840 @item @code{ssl-ca-location} (default: @code{"/etc/ssl/certs/ca-certificates.crt"}) (type: string)
27841 The location of certificate authority (CA) files for SSL server
27842 certificate verification.
27844 @item @code{ssl-cert-location} (default: @code{"/etc/ssl/certs"}) (type: string)
27845 Location of SSL client certificates.
27847 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27848 Extra options will be appended to Zabbix server configuration file.
27850 @item @code{include-files} (default: @code{()}) (type: include-files)
27851 You may include individual files or all files in a directory in the
27852 configuration file.
27859 @c %end of fragment
27861 @anchor{zabbix-agent}
27862 @subsubheading Zabbix agent
27863 @cindex zabbix zabbix-agent
27865 The Zabbix agent gathers information about the running system for the Zabbix
27866 monitoring server. It has a variety of built-in checks, and can be extended
27868 @uref{https://www.zabbix.com/documentation/current/en/manual/config/items/userparameters,
27869 @dfn{user parameters}}.
27871 @defvar {Scheme variable} zabbix-agent-service-type
27872 This is the service type for the Zabbix agent service. Its value must be a
27873 @code{zabbix-agent-configuration} record, shown below.
27876 @c %start of fragment
27878 @deftp {Data Type} zabbix-agent-configuration
27879 Available @code{zabbix-agent-configuration} fields are:
27882 @item @code{zabbix-agent} (default: @code{zabbix-agentd}) (type: file-like)
27883 The zabbix-agent package.
27885 @item @code{user} (default: @code{"zabbix"}) (type: string)
27886 User who will run the Zabbix agent.
27888 @item @code{group} (default: @code{"zabbix"}) (type: group)
27889 Group who will run the Zabbix agent.
27891 @item @code{hostname} (default: @code{""}) (type: string)
27892 Unique, case sensitive hostname which is required for active checks and
27893 must match hostname as configured on the server.
27895 @item @code{log-type} (default: @code{""}) (type: string)
27896 Specifies where log messages are written to:
27900 @code{system} - syslog.
27902 @item @code{file} - file specified with
27903 @code{log-file} parameter.
27905 @item @code{console} - standard output.
27909 @item @code{log-file} (default: @code{"/var/log/zabbix/agent.log"}) (type: string)
27910 Log file name for @code{log-type} @code{file} parameter.
27912 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_agent.pid"}) (type: string)
27915 @item @code{server} (default: @code{("127.0.0.1")}) (type: list)
27916 List of IP addresses, optionally in CIDR notation, or hostnames of
27917 Zabbix servers and Zabbix proxies. Incoming connections will be
27918 accepted only from the hosts listed here.
27920 @item @code{server-active} (default: @code{("127.0.0.1")}) (type: list)
27921 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
27922 proxies for active checks. If port is not specified, default port is
27923 used. If this parameter is not specified, active checks are disabled.
27925 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27926 Extra options will be appended to Zabbix server configuration file.
27928 @item @code{include-files} (default: @code{()}) (type: include-files)
27929 You may include individual files or all files in a directory in the
27930 configuration file.
27937 @c %end of fragment
27939 @anchor{zabbix-front-end}
27940 @subsubheading Zabbix front-end
27941 @cindex zabbix zabbix-front-end
27943 The Zabbix front-end provides a web interface to Zabbix. It does not need
27944 to run on the same machine as the Zabbix server. This service works by
27945 extending the @ref{PHP-FPM} and @ref{NGINX} services with the configuration
27946 necessary for loading the Zabbix user interface.
27948 @defvar {Scheme variable} zabbix-front-end-service-type
27949 This is the service type for the Zabbix web frontend. Its value must be a
27950 @code{zabbix-front-end-configuration} record, shown below.
27953 @c %start of fragment
27955 @deftp {Data Type} zabbix-front-end-configuration
27956 Available @code{zabbix-front-end-configuration} fields are:
27959 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27960 The Zabbix server package to use.
27962 @item @code{nginx} (default: @code{()}) (type: list)
27963 List of @ref{nginx-server-configuration,@code{nginx-server-configuration}}
27964 blocks for the Zabbix front-end. When empty, a default that listens on
27967 @item @code{db-host} (default: @code{"localhost"}) (type: string)
27968 Database host name.
27970 @item @code{db-port} (default: @code{5432}) (type: number)
27973 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27976 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27979 @item @code{db-password} (default: @code{""}) (type: string)
27980 Database password. Please, use @code{db-secret-file} instead.
27982 @item @code{db-secret-file} (default: @code{""}) (type: string)
27983 Secret file which will be appended to @file{zabbix.conf.php} file. This
27984 file contains credentials for use by Zabbix front-end. You are expected
27985 to create it manually.
27987 @item @code{zabbix-host} (default: @code{"localhost"}) (type: string)
27988 Zabbix server hostname.
27990 @item @code{zabbix-port} (default: @code{10051}) (type: number)
27991 Zabbix server port.
27998 @c %end of fragment
28000 @node Kerberos Services
28001 @subsection Kerberos Services
28004 The @code{(gnu services kerberos)} module provides services relating to
28005 the authentication protocol @dfn{Kerberos}.
28007 @subsubheading Krb5 Service
28009 Programs using a Kerberos client library normally
28010 expect a configuration file in @file{/etc/krb5.conf}.
28011 This service generates such a file from a definition provided in the
28012 operating system declaration.
28013 It does not cause any daemon to be started.
28015 No ``keytab'' files are provided by this service---you must explicitly create them.
28016 This service is known to work with the MIT client library, @code{mit-krb5}.
28017 Other implementations have not been tested.
28019 @defvr {Scheme Variable} krb5-service-type
28020 A service type for Kerberos 5 clients.
28024 Here is an example of its use:
28026 (service krb5-service-type
28027 (krb5-configuration
28028 (default-realm "EXAMPLE.COM")
28029 (allow-weak-crypto? #t)
28032 (name "EXAMPLE.COM")
28033 (admin-server "groucho.example.com")
28034 (kdc "karl.example.com"))
28037 (admin-server "kerb-admin.argrx.edu")
28038 (kdc "keys.argrx.edu"))))))
28042 This example provides a Kerberos@tie{}5 client configuration which:
28044 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
28045 of which have distinct administration servers and key distribution centers;
28046 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
28047 specified by clients;
28048 @item Accepts services which only support encryption types known to be weak.
28051 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
28052 Only the most commonly used ones are described here.
28053 For a full list, and more detailed explanation of each, see the MIT
28054 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
28058 @deftp {Data Type} krb5-realm
28059 @cindex realm, kerberos
28062 This field is a string identifying the name of the realm.
28063 A common convention is to use the fully qualified DNS name of your organization,
28064 converted to upper case.
28066 @item @code{admin-server}
28067 This field is a string identifying the host where the administration server is
28071 This field is a string identifying the key distribution center
28076 @deftp {Data Type} krb5-configuration
28079 @item @code{allow-weak-crypto?} (default: @code{#f})
28080 If this flag is @code{#t} then services which only offer encryption algorithms
28081 known to be weak will be accepted.
28083 @item @code{default-realm} (default: @code{#f})
28084 This field should be a string identifying the default Kerberos
28085 realm for the client.
28086 You should set this field to the name of your Kerberos realm.
28087 If this value is @code{#f}
28088 then a realm must be specified with every Kerberos principal when invoking programs
28089 such as @command{kinit}.
28091 @item @code{realms}
28092 This should be a non-empty list of @code{krb5-realm} objects, which clients may
28094 Normally, one of them will have a @code{name} field matching the @code{default-realm}
28100 @subsubheading PAM krb5 Service
28103 The @code{pam-krb5} service allows for login authentication and password
28104 management via Kerberos.
28105 You will need this service if you want PAM enabled applications to authenticate
28106 users using Kerberos.
28108 @defvr {Scheme Variable} pam-krb5-service-type
28109 A service type for the Kerberos 5 PAM module.
28112 @deftp {Data Type} pam-krb5-configuration
28113 Data type representing the configuration of the Kerberos 5 PAM module.
28114 This type has the following parameters:
28116 @item @code{pam-krb5} (default: @code{pam-krb5})
28117 The pam-krb5 package to use.
28119 @item @code{minimum-uid} (default: @code{1000})
28120 The smallest user ID for which Kerberos authentications should be attempted.
28121 Local accounts with lower values will silently fail to authenticate.
28126 @node LDAP Services
28127 @subsection LDAP Services
28129 @cindex nslcd, LDAP service
28131 The @code{(gnu services authentication)} module provides the
28132 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
28133 server. In addition to configuring the service itself, you may want to add
28134 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
28135 Switch} for detailed information.
28137 Here is a simple operating system declaration with a default configuration of
28138 the @code{nslcd-service-type} and a Name Service Switch configuration that
28139 consults the @code{ldap} name service last:
28142 (use-service-modules authentication)
28143 (use-modules (gnu system nss))
28149 (service nslcd-service-type)
28150 (service dhcp-client-service-type)
28152 (name-service-switch
28153 (let ((services (list (name-service (name "db"))
28154 (name-service (name "files"))
28155 (name-service (name "ldap")))))
28156 (name-service-switch
28157 (inherit %mdns-host-lookup-nss)
28158 (password services)
28161 (netgroup services)
28162 (gshadow services)))))
28165 @c %start of generated documentation for nslcd-configuration
28167 Available @code{nslcd-configuration} fields are:
28169 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
28170 The @code{nss-pam-ldapd} package to use.
28174 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
28175 The number of threads to start that can handle requests and perform LDAP
28176 queries. Each thread opens a separate connection to the LDAP server.
28177 The default is to start 5 threads.
28179 Defaults to @samp{disabled}.
28183 @deftypevr {@code{nslcd-configuration} parameter} string uid
28184 This specifies the user id with which the daemon should be run.
28186 Defaults to @samp{"nslcd"}.
28190 @deftypevr {@code{nslcd-configuration} parameter} string gid
28191 This specifies the group id with which the daemon should be run.
28193 Defaults to @samp{"nslcd"}.
28197 @deftypevr {@code{nslcd-configuration} parameter} log-option log
28198 This option controls the way logging is done via a list containing
28199 SCHEME and LEVEL@. The SCHEME argument may either be the symbols
28200 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
28201 argument is optional and specifies the log level. The log level may be
28202 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
28203 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
28204 specified log level or higher are logged.
28206 Defaults to @samp{("/var/log/nslcd" info)}.
28210 @deftypevr {@code{nslcd-configuration} parameter} list uri
28211 The list of LDAP server URIs. Normally, only the first server will be
28212 used with the following servers as fall-back.
28214 Defaults to @samp{("ldap://localhost:389/")}.
28218 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
28219 The version of the LDAP protocol to use. The default is to use the
28220 maximum version supported by the LDAP library.
28222 Defaults to @samp{disabled}.
28226 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
28227 Specifies the distinguished name with which to bind to the directory
28228 server for lookups. The default is to bind anonymously.
28230 Defaults to @samp{disabled}.
28234 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
28235 Specifies the credentials with which to bind. This option is only
28236 applicable when used with binddn.
28238 Defaults to @samp{disabled}.
28242 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
28243 Specifies the distinguished name to use when the root user tries to
28244 modify a user's password using the PAM module.
28246 Defaults to @samp{disabled}.
28250 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
28251 Specifies the credentials with which to bind if the root user tries to
28252 change a user's password. This option is only applicable when used with
28255 Defaults to @samp{disabled}.
28259 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
28260 Specifies the SASL mechanism to be used when performing SASL
28263 Defaults to @samp{disabled}.
28267 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
28268 Specifies the SASL realm to be used when performing SASL authentication.
28270 Defaults to @samp{disabled}.
28274 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
28275 Specifies the authentication identity to be used when performing SASL
28278 Defaults to @samp{disabled}.
28282 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
28283 Specifies the authorization identity to be used when performing SASL
28286 Defaults to @samp{disabled}.
28290 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
28291 Determines whether the LDAP server host name should be canonicalised. If
28292 this is enabled the LDAP library will do a reverse host name lookup. By
28293 default, it is left up to the LDAP library whether this check is
28296 Defaults to @samp{disabled}.
28300 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
28301 Set the name for the GSS-API Kerberos credentials cache.
28303 Defaults to @samp{disabled}.
28307 @deftypevr {@code{nslcd-configuration} parameter} string base
28308 The directory search base.
28310 Defaults to @samp{"dc=example,dc=com"}.
28314 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
28315 Specifies the search scope (subtree, onelevel, base or children). The
28316 default scope is subtree; base scope is almost never useful for name
28317 service lookups; children scope is not supported on all servers.
28319 Defaults to @samp{(subtree)}.
28323 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
28324 Specifies the policy for dereferencing aliases. The default policy is
28325 to never dereference aliases.
28327 Defaults to @samp{disabled}.
28331 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
28332 Specifies whether automatic referral chasing should be enabled. The
28333 default behaviour is to chase referrals.
28335 Defaults to @samp{disabled}.
28339 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
28340 This option allows for custom attributes to be looked up instead of the
28341 default RFC 2307 attributes. It is a list of maps, each consisting of
28342 the name of a map, the RFC 2307 attribute to match and the query
28343 expression for the attribute as it is available in the directory.
28345 Defaults to @samp{()}.
28349 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
28350 A list of filters consisting of the name of a map to which the filter
28351 applies and an LDAP search filter expression.
28353 Defaults to @samp{()}.
28357 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
28358 Specifies the time limit in seconds to use when connecting to the
28359 directory server. The default value is 10 seconds.
28361 Defaults to @samp{disabled}.
28365 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
28366 Specifies the time limit (in seconds) to wait for a response from the
28367 LDAP server. A value of zero, which is the default, is to wait
28368 indefinitely for searches to be completed.
28370 Defaults to @samp{disabled}.
28374 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
28375 Specifies the period if inactivity (in seconds) after which the con‐
28376 nection to the LDAP server will be closed. The default is not to time
28379 Defaults to @samp{disabled}.
28383 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
28384 Specifies the number of seconds to sleep when connecting to all LDAP
28385 servers fails. By default one second is waited between the first
28386 failure and the first retry.
28388 Defaults to @samp{disabled}.
28392 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
28393 Specifies the time after which the LDAP server is considered to be
28394 permanently unavailable. Once this time is reached retries will be done
28395 only once per this time period. The default value is 10 seconds.
28397 Defaults to @samp{disabled}.
28401 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
28402 Specifies whether to use SSL/TLS or not (the default is not to). If
28403 'start-tls is specified then StartTLS is used rather than raw LDAP over
28406 Defaults to @samp{disabled}.
28410 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
28411 Specifies what checks to perform on a server-supplied certificate. The
28412 meaning of the values is described in the ldap.conf(5) manual page.
28414 Defaults to @samp{disabled}.
28418 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
28419 Specifies the directory containing X.509 certificates for peer authen‐
28420 tication. This parameter is ignored when using GnuTLS.
28422 Defaults to @samp{disabled}.
28426 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
28427 Specifies the path to the X.509 certificate for peer authentication.
28429 Defaults to @samp{disabled}.
28433 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
28434 Specifies the path to an entropy source. This parameter is ignored when
28437 Defaults to @samp{disabled}.
28441 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
28442 Specifies the ciphers to use for TLS as a string.
28444 Defaults to @samp{disabled}.
28448 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
28449 Specifies the path to the file containing the local certificate for
28450 client TLS authentication.
28452 Defaults to @samp{disabled}.
28456 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
28457 Specifies the path to the file containing the private key for client TLS
28460 Defaults to @samp{disabled}.
28464 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
28465 Set this to a number greater than 0 to request paged results from the
28466 LDAP server in accordance with RFC2696. The default (0) is to not
28467 request paged results.
28469 Defaults to @samp{disabled}.
28473 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
28474 This option prevents group membership lookups through LDAP for the
28475 specified users. Alternatively, the value 'all-local may be used. With
28476 that value nslcd builds a full list of non-LDAP users on startup.
28478 Defaults to @samp{disabled}.
28482 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
28483 This option ensures that LDAP users with a numeric user id lower than
28484 the specified value are ignored.
28486 Defaults to @samp{disabled}.
28490 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
28491 This option specifies an offset that is added to all LDAP numeric user
28492 ids. This can be used to avoid user id collisions with local users.
28494 Defaults to @samp{disabled}.
28498 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
28499 This option specifies an offset that is added to all LDAP numeric group
28500 ids. This can be used to avoid user id collisions with local groups.
28502 Defaults to @samp{disabled}.
28506 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
28507 If this option is set, the member attribute of a group may point to
28508 another group. Members of nested groups are also returned in the higher
28509 level group and parent groups are returned when finding groups for a
28510 specific user. The default is not to perform extra searches for nested
28513 Defaults to @samp{disabled}.
28517 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
28518 If this option is set, the group member list is not retrieved when
28519 looking up groups. Lookups for finding which groups a user belongs to
28520 will remain functional so the user will likely still get the correct
28521 groups assigned on login.
28523 Defaults to @samp{disabled}.
28527 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
28528 If this option is set, functions which cause all user/group entries to
28529 be loaded from the directory will not succeed in doing so. This can
28530 dramatically reduce LDAP server load in situations where there are a
28531 great number of users and/or groups. This option is not recommended for
28532 most configurations.
28534 Defaults to @samp{disabled}.
28538 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
28539 This option can be used to specify how user and group names are verified
28540 within the system. This pattern is used to check all user and group
28541 names that are requested and returned from LDAP.
28543 Defaults to @samp{disabled}.
28547 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
28548 This specifies whether or not to perform searches using case-insensitive
28549 matching. Enabling this could open up the system to authorization
28550 bypass vulnerabilities and introduce nscd cache poisoning
28551 vulnerabilities which allow denial of service.
28553 Defaults to @samp{disabled}.
28557 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
28558 This option specifies whether password policy controls are requested and
28559 handled from the LDAP server when performing user authentication.
28561 Defaults to @samp{disabled}.
28565 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
28566 By default nslcd performs an LDAP search with the user's credentials
28567 after BIND (authentication) to ensure that the BIND operation was
28568 successful. The default search is a simple check to see if the user's
28569 DN exists. A search filter can be specified that will be used instead.
28570 It should return at least one entry.
28572 Defaults to @samp{disabled}.
28576 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
28577 This option allows flexible fine tuning of the authorisation check that
28578 should be performed. The search filter specified is executed and if any
28579 entries match, access is granted, otherwise access is denied.
28581 Defaults to @samp{disabled}.
28585 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
28586 If this option is set password modification using pam_ldap will be
28587 denied and the specified message will be presented to the user instead.
28588 The message can be used to direct the user to an alternative means of
28589 changing their password.
28591 Defaults to @samp{disabled}.
28595 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
28596 List of pam service names for which LDAP authentication should suffice.
28598 Defaults to @samp{()}.
28602 @c %end of generated documentation for nslcd-configuration
28606 @subsection Web Services
28611 The @code{(gnu services web)} module provides the Apache HTTP Server,
28612 the nginx web server, and also a fastcgi wrapper daemon.
28614 @subsubheading Apache HTTP Server
28616 @deffn {Scheme Variable} httpd-service-type
28617 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
28618 (@dfn{httpd}). The value for this service type is a
28619 @code{httpd-configuration} record.
28621 A simple example configuration is given below.
28624 (service httpd-service-type
28625 (httpd-configuration
28628 (server-name "www.example.com")
28629 (document-root "/srv/http/www.example.com")))))
28632 Other services can also extend the @code{httpd-service-type} to add to
28636 (simple-service 'www.example.com-server httpd-service-type
28640 (list (string-join '("ServerName www.example.com"
28641 "DocumentRoot /srv/http/www.example.com")
28646 The details for the @code{httpd-configuration}, @code{httpd-module},
28647 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
28650 @deffn {Data Type} httpd-configuration
28651 This data type represents the configuration for the httpd service.
28654 @item @code{package} (default: @code{httpd})
28655 The httpd package to use.
28657 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28658 The pid file used by the shepherd-service.
28660 @item @code{config} (default: @code{(httpd-config-file)})
28661 The configuration file to use with the httpd service. The default value
28662 is a @code{httpd-config-file} record, but this can also be a different
28663 G-expression that generates a file, for example a @code{plain-file}. A
28664 file outside of the store can also be specified through a string.
28669 @deffn {Data Type} httpd-module
28670 This data type represents a module for the httpd service.
28674 The name of the module.
28677 The file for the module. This can be relative to the httpd package being
28678 used, the absolute location of a file, or a G-expression for a file
28679 within the store, for example @code{(file-append mod-wsgi
28680 "/modules/mod_wsgi.so")}.
28685 @defvr {Scheme Variable} %default-httpd-modules
28686 A default list of @code{httpd-module} objects.
28689 @deffn {Data Type} httpd-config-file
28690 This data type represents a configuration file for the httpd service.
28693 @item @code{modules} (default: @code{%default-httpd-modules})
28694 The modules to load. Additional modules can be added here, or loaded by
28695 additional configuration.
28697 For example, in order to handle requests for PHP files, you can use Apache’s
28698 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
28701 (service httpd-service-type
28702 (httpd-configuration
28707 (name "proxy_module")
28708 (file "modules/mod_proxy.so"))
28710 (name "proxy_fcgi_module")
28711 (file "modules/mod_proxy_fcgi.so"))
28712 %default-httpd-modules))
28713 (extra-config (list "\
28714 <FilesMatch \\.php$>
28715 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
28716 </FilesMatch>"))))))
28717 (service php-fpm-service-type
28718 (php-fpm-configuration
28719 (socket "/var/run/php-fpm.sock")
28720 (socket-group "httpd")))
28723 @item @code{server-root} (default: @code{httpd})
28724 The @code{ServerRoot} in the configuration file, defaults to the httpd
28725 package. Directives including @code{Include} and @code{LoadModule} are
28726 taken as relative to the server root.
28728 @item @code{server-name} (default: @code{#f})
28729 The @code{ServerName} in the configuration file, used to specify the
28730 request scheme, hostname and port that the server uses to identify
28733 This doesn't need to be set in the server config, and can be specified
28734 in virtual hosts. The default is @code{#f} to not specify a
28737 @item @code{document-root} (default: @code{"/srv/http"})
28738 The @code{DocumentRoot} from which files will be served.
28740 @item @code{listen} (default: @code{'("80")})
28741 The list of values for the @code{Listen} directives in the config
28742 file. The value should be a list of strings, when each string can
28743 specify the port number to listen on, and optionally the IP address and
28746 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28747 The @code{PidFile} to use. This should match the @code{pid-file} set in
28748 the @code{httpd-configuration} so that the Shepherd service is
28749 configured correctly.
28751 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
28752 The @code{ErrorLog} to which the server will log errors.
28754 @item @code{user} (default: @code{"httpd"})
28755 The @code{User} which the server will answer requests as.
28757 @item @code{group} (default: @code{"httpd"})
28758 The @code{Group} which the server will answer requests as.
28760 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
28761 A flat list of strings and G-expressions which will be added to the end
28762 of the configuration file.
28764 Any values which the service is extended with will be appended to this
28770 @deffn {Data Type} httpd-virtualhost
28771 This data type represents a virtualhost configuration block for the httpd service.
28773 These should be added to the extra-config for the httpd-service.
28776 (simple-service 'www.example.com-server httpd-service-type
28780 (list (string-join '("ServerName www.example.com"
28781 "DocumentRoot /srv/http/www.example.com")
28786 @item @code{addresses-and-ports}
28787 The addresses and ports for the @code{VirtualHost} directive.
28789 @item @code{contents}
28790 The contents of the @code{VirtualHost} directive, this should be a list
28791 of strings and G-expressions.
28797 @subsubheading NGINX
28799 @deffn {Scheme Variable} nginx-service-type
28800 Service type for the @uref{https://nginx.org/,NGinx} web server. The
28801 value for this service type is a @code{<nginx-configuration>} record.
28803 A simple example configuration is given below.
28806 (service nginx-service-type
28807 (nginx-configuration
28809 (list (nginx-server-configuration
28810 (server-name '("www.example.com"))
28811 (root "/srv/http/www.example.com"))))))
28814 In addition to adding server blocks to the service configuration
28815 directly, this service can be extended by other services to add server
28816 blocks, as in this example:
28819 (simple-service 'my-extra-server nginx-service-type
28820 (list (nginx-server-configuration
28821 (root "/srv/http/extra-website")
28822 (try-files (list "$uri" "$uri/index.html")))))
28826 At startup, @command{nginx} has not yet read its configuration file, so
28827 it uses a default file to log error messages. If it fails to load its
28828 configuration file, that is where error messages are logged. After the
28829 configuration file is loaded, the default error log file changes as per
28830 configuration. In our case, startup error messages can be found in
28831 @file{/var/run/nginx/logs/error.log}, and after configuration in
28832 @file{/var/log/nginx/error.log}. The second location can be changed
28833 with the @var{log-directory} configuration option.
28835 @deffn {Data Type} nginx-configuration
28836 This data type represents the configuration for NGinx. Some
28837 configuration can be done through this and the other provided record
28838 types, or alternatively, a config file can be provided.
28841 @item @code{nginx} (default: @code{nginx})
28842 The nginx package to use.
28844 @item @code{shepherd-requirement} (default: @code{'()})
28845 This is a list of symbols naming Shepherd services the nginx service
28848 This is useful if you would like @command{nginx} to be started after a
28849 back-end web server or a logging service such as Anonip has been
28852 @item @code{log-directory} (default: @code{"/var/log/nginx"})
28853 The directory to which NGinx will write log files.
28855 @item @code{run-directory} (default: @code{"/var/run/nginx"})
28856 The directory in which NGinx will create a pid file, and write temporary
28859 @item @code{server-blocks} (default: @code{'()})
28860 A list of @dfn{server blocks} to create in the generated configuration
28861 file, the elements should be of type
28862 @code{<nginx-server-configuration>}.
28864 The following example would setup NGinx to serve @code{www.example.com}
28865 from the @code{/srv/http/www.example.com} directory, without using
28868 (service nginx-service-type
28869 (nginx-configuration
28871 (list (nginx-server-configuration
28872 (server-name '("www.example.com"))
28873 (root "/srv/http/www.example.com"))))))
28876 @item @code{upstream-blocks} (default: @code{'()})
28877 A list of @dfn{upstream blocks} to create in the generated configuration
28878 file, the elements should be of type
28879 @code{<nginx-upstream-configuration>}.
28881 Configuring upstreams through the @code{upstream-blocks} can be useful
28882 when combined with @code{locations} in the
28883 @code{<nginx-server-configuration>} records. The following example
28884 creates a server configuration with one location configuration, that
28885 will proxy requests to a upstream configuration, which will handle
28886 requests with two servers.
28891 (nginx-configuration
28893 (list (nginx-server-configuration
28894 (server-name '("www.example.com"))
28895 (root "/srv/http/www.example.com")
28898 (nginx-location-configuration
28900 (body '("proxy_pass http://server-proxy;"))))))))
28902 (list (nginx-upstream-configuration
28903 (name "server-proxy")
28904 (servers (list "server1.example.com"
28905 "server2.example.com")))))))
28908 @item @code{file} (default: @code{#f})
28909 If a configuration @var{file} is provided, this will be used, rather than
28910 generating a configuration file from the provided @code{log-directory},
28911 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
28912 proper operation, these arguments should match what is in @var{file} to ensure
28913 that the directories are created when the service is activated.
28915 This can be useful if you have an existing configuration file, or it's
28916 not possible to do what is required through the other parts of the
28917 nginx-configuration record.
28919 @item @code{server-names-hash-bucket-size} (default: @code{#f})
28920 Bucket size for the server names hash tables, defaults to @code{#f} to
28921 use the size of the processors cache line.
28923 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
28924 Maximum bucket size for the server names hash tables.
28926 @item @code{modules} (default: @code{'()})
28927 List of nginx dynamic modules to load. This should be a list of file
28928 names of loadable modules, as in this example:
28933 (file-append nginx-accept-language-module "\
28934 /etc/nginx/modules/ngx_http_accept_language_module.so")
28935 (file-append nginx-lua-module "\
28936 /etc/nginx/modules/ngx_http_lua_module.so")))
28939 @item @code{lua-package-path} (default: @code{'()})
28940 List of nginx lua packages to load. This should be a list of package
28941 names of loadable lua modules, as in this example:
28944 (lua-package-path (list lua-resty-core
28951 @item @code{lua-package-cpath} (default: @code{'()})
28952 List of nginx lua C packages to load. This should be a list of package
28953 names of loadable lua C modules, as in this example:
28956 (lua-package-cpath (list lua-resty-signal))
28959 @item @code{global-directives} (default: @code{'((events . ()))})
28960 Association list of global directives for the top level of the nginx
28961 configuration. Values may themselves be association lists.
28965 `((worker_processes . 16)
28967 (events . ((worker_connections . 1024)))))
28970 @item @code{extra-content} (default: @code{""})
28971 Extra content for the @code{http} block. Should be string or a string
28972 valued G-expression.
28977 @anchor{nginx-server-configuration}
28978 @deftp {Data Type} nginx-server-configuration
28979 Data type representing the configuration of an nginx server block.
28980 This type has the following parameters:
28983 @item @code{listen} (default: @code{'("80" "443 ssl")})
28984 Each @code{listen} directive sets the address and port for IP, or the
28985 path for a UNIX-domain socket on which the server will accept requests.
28986 Both address and port, or only address or only port can be specified.
28987 An address may also be a hostname, for example:
28990 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
28993 @item @code{server-name} (default: @code{(list 'default)})
28994 A list of server names this server represents. @code{'default} represents the
28995 default server for connections matching no other server.
28997 @item @code{root} (default: @code{"/srv/http"})
28998 Root of the website nginx will serve.
29000 @item @code{locations} (default: @code{'()})
29001 A list of @dfn{nginx-location-configuration} or
29002 @dfn{nginx-named-location-configuration} records to use within this
29005 @item @code{index} (default: @code{(list "index.html")})
29006 Index files to look for when clients ask for a directory. If it cannot be found,
29007 Nginx will send the list of files in the directory.
29009 @item @code{try-files} (default: @code{'()})
29010 A list of files whose existence is checked in the specified order.
29011 @code{nginx} will use the first file it finds to process the request.
29013 @item @code{ssl-certificate} (default: @code{#f})
29014 Where to find the certificate for secure connections. Set it to @code{#f} if
29015 you don't have a certificate or you don't want to use HTTPS.
29017 @item @code{ssl-certificate-key} (default: @code{#f})
29018 Where to find the private key for secure connections. Set it to @code{#f} if
29019 you don't have a key or you don't want to use HTTPS.
29021 @item @code{server-tokens?} (default: @code{#f})
29022 Whether the server should add its configuration to response.
29024 @item @code{raw-content} (default: @code{'()})
29025 A list of raw lines added to the server block.
29030 @deftp {Data Type} nginx-upstream-configuration
29031 Data type representing the configuration of an nginx @code{upstream}
29032 block. This type has the following parameters:
29036 Name for this group of servers.
29038 @item @code{servers}
29039 Specify the addresses of the servers in the group. The address can be
29040 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
29041 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
29042 prefix @samp{unix:}. For addresses using an IP address or domain name,
29043 the default port is 80, and a different port can be specified
29046 @item @code{extra-content}
29047 A string or list of strings to add to the upstream block.
29052 @deftp {Data Type} nginx-location-configuration
29053 Data type representing the configuration of an nginx @code{location}
29054 block. This type has the following parameters:
29058 URI which this location block matches.
29060 @anchor{nginx-location-configuration body}
29062 Body of the location block, specified as a list of strings. This can contain
29064 configuration directives. For example, to pass requests to a upstream
29065 server group defined using an @code{nginx-upstream-configuration} block,
29066 the following directive would be specified in the body @samp{(list "proxy_pass
29067 http://upstream-name;")}.
29072 @deftp {Data Type} nginx-named-location-configuration
29073 Data type representing the configuration of an nginx named location
29074 block. Named location blocks are used for request redirection, and not
29075 used for regular request processing. This type has the following
29080 Name to identify this location block.
29083 @xref{nginx-location-configuration body}, as the body for named location
29084 blocks can be used in a similar way to the
29085 @code{nginx-location-configuration body}. One restriction is that the
29086 body of a named location block cannot contain location blocks.
29091 @subsubheading Varnish Cache
29093 Varnish is a fast cache server that sits in between web applications
29094 and end users. It proxies requests from clients and caches the
29095 accessed URLs such that multiple requests for the same resource only
29096 creates one request to the back-end.
29098 @defvr {Scheme Variable} varnish-service-type
29099 Service type for the Varnish daemon.
29102 @deftp {Data Type} varnish-configuration
29103 Data type representing the @code{varnish} service configuration.
29104 This type has the following parameters:
29107 @item @code{package} (default: @code{varnish})
29108 The Varnish package to use.
29110 @item @code{name} (default: @code{"default"})
29111 A name for this Varnish instance. Varnish will create a directory in
29112 @file{/var/varnish/} with this name and keep temporary files there. If
29113 the name starts with a forward slash, it is interpreted as an absolute
29116 Pass the @code{-n} argument to other Varnish programs to connect to the
29117 named instance, e.g.@: @command{varnishncsa -n default}.
29119 @item @code{backend} (default: @code{"localhost:8080"})
29120 The backend to use. This option has no effect if @code{vcl} is set.
29122 @item @code{vcl} (default: #f)
29123 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
29124 is @code{#f}, Varnish will proxy @code{backend} using the default
29125 configuration. Otherwise this must be a file-like object with valid
29128 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
29129 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
29130 can do something along these lines:
29133 (define %gnu-mirror
29134 (plain-file "gnu.vcl"
29136 backend gnu @{ .host = \"www.gnu.org\"; @}"))
29140 (services (cons (service varnish-service-type
29141 (varnish-configuration
29143 (vcl %gnu-mirror)))
29147 The configuration of an already running Varnish instance can be inspected
29148 and changed using the @command{varnishadm} program.
29150 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
29151 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
29152 comprehensive documentation on Varnish and its configuration language.
29154 @item @code{listen} (default: @code{'("localhost:80")})
29155 List of addresses Varnish will listen on.
29157 @item @code{storage} (default: @code{'("malloc,128m")})
29158 List of storage backends that will be available in VCL.
29160 @item @code{parameters} (default: @code{'()})
29161 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
29163 @item @code{extra-options} (default: @code{'()})
29164 Additional arguments to pass to the @command{varnishd} process.
29169 @subsubheading Patchwork
29171 Patchwork is a patch tracking system. It can collect patches sent to a
29172 mailing list, and display them in a web interface.
29174 @defvr {Scheme Variable} patchwork-service-type
29175 Service type for Patchwork.
29178 The following example is an example of a minimal service for Patchwork, for
29179 the @code{patchwork.example.com} domain.
29182 (service patchwork-service-type
29183 (patchwork-configuration
29184 (domain "patchwork.example.com")
29186 (patchwork-settings-module
29187 (allowed-hosts (list domain))
29188 (default-from-email "patchwork@@patchwork.example.com")))
29189 (getmail-retriever-config
29190 (getmail-retriever-configuration
29191 (type "SimpleIMAPSSLRetriever")
29192 (server "imap.example.com")
29194 (username "patchwork")
29196 (list (file-append coreutils "/bin/cat")
29197 "/etc/getmail-patchwork-imap-password"))
29199 '((mailboxes . ("Patches"))))))))
29203 There are three records for configuring the Patchwork service. The
29204 @code{<patchwork-configuration>} relates to the configuration for Patchwork
29205 within the HTTPD service.
29207 The @code{settings-module} field within the @code{<patchwork-configuration>}
29208 record can be populated with the @code{<patchwork-settings-module>} record,
29209 which describes a settings module that is generated within the Guix store.
29211 For the @code{database-configuration} field within the
29212 @code{<patchwork-settings-module>}, the
29213 @code{<patchwork-database-configuration>} must be used.
29215 @deftp {Data Type} patchwork-configuration
29216 Data type representing the Patchwork service configuration. This type has the
29217 following parameters:
29220 @item @code{patchwork} (default: @code{patchwork})
29221 The Patchwork package to use.
29223 @item @code{domain}
29224 The domain to use for Patchwork, this is used in the HTTPD service virtual
29227 @item @code{settings-module}
29228 The settings module to use for Patchwork. As a Django application, Patchwork
29229 is configured with a Python module containing the settings. This can either be
29230 an instance of the @code{<patchwork-settings-module>} record, any other record
29231 that represents the settings in the store, or a directory outside of the
29234 @item @code{static-path} (default: @code{"/static/"})
29235 The path under which the HTTPD service should serve the static files.
29237 @item @code{getmail-retriever-config}
29238 The getmail-retriever-configuration record value to use with
29239 Patchwork. Getmail will be configured with this value, the messages will be
29240 delivered to Patchwork.
29245 @deftp {Data Type} patchwork-settings-module
29246 Data type representing a settings module for Patchwork. Some of these
29247 settings relate directly to Patchwork, but others relate to Django, the web
29248 framework used by Patchwork, or the Django Rest Framework library. This type
29249 has the following parameters:
29252 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
29253 The database connection settings used for Patchwork. See the
29254 @code{<patchwork-database-configuration>} record type for more information.
29256 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
29257 Patchwork, as a Django web application uses a secret key for cryptographically
29258 signing values. This file should contain a unique unpredictable value.
29260 If this file does not exist, it will be created and populated with a random
29261 value by the patchwork-setup shepherd service.
29263 This setting relates to Django.
29265 @item @code{allowed-hosts}
29266 A list of valid hosts for this Patchwork service. This should at least include
29267 the domain specified in the @code{<patchwork-configuration>} record.
29269 This is a Django setting.
29271 @item @code{default-from-email}
29272 The email address from which Patchwork should send email by default.
29274 This is a Patchwork setting.
29276 @item @code{static-url} (default: @code{#f})
29277 The URL to use when serving static assets. It can be part of a URL, or a full
29278 URL, but must end in a @code{/}.
29280 If the default value is used, the @code{static-path} value from the
29281 @code{<patchwork-configuration>} record will be used.
29283 This is a Django setting.
29285 @item @code{admins} (default: @code{'()})
29286 Email addresses to send the details of errors that occur. Each value should
29287 be a list containing two elements, the name and then the email address.
29289 This is a Django setting.
29291 @item @code{debug?} (default: @code{#f})
29292 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
29293 messages will be shown.
29295 This is a Django setting.
29297 @item @code{enable-rest-api?} (default: @code{#t})
29298 Whether to enable the Patchwork REST API.
29300 This is a Patchwork setting.
29302 @item @code{enable-xmlrpc?} (default: @code{#t})
29303 Whether to enable the XML RPC API.
29305 This is a Patchwork setting.
29307 @item @code{force-https-links?} (default: @code{#t})
29308 Whether to use HTTPS links on Patchwork pages.
29310 This is a Patchwork setting.
29312 @item @code{extra-settings} (default: @code{""})
29313 Extra code to place at the end of the Patchwork settings module.
29318 @deftp {Data Type} patchwork-database-configuration
29319 Data type representing the database configuration for Patchwork.
29322 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
29323 The database engine to use.
29325 @item @code{name} (default: @code{"patchwork"})
29326 The name of the database to use.
29328 @item @code{user} (default: @code{"httpd"})
29329 The user to connect to the database as.
29331 @item @code{password} (default: @code{""})
29332 The password to use when connecting to the database.
29334 @item @code{host} (default: @code{""})
29335 The host to make the database connection to.
29337 @item @code{port} (default: @code{""})
29338 The port on which to connect to the database.
29343 @subsubheading Mumi
29345 @cindex Mumi, Debbugs Web interface
29346 @cindex Debbugs, Mumi Web interface
29347 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
29348 Web interface to the Debbugs bug tracker, by default for
29349 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
29350 but it also fetches and indexes mail retrieved from Debbugs.
29352 @defvr {Scheme Variable} mumi-service-type
29353 This is the service type for Mumi.
29356 @deftp {Data Type} mumi-configuration
29357 Data type representing the Mumi service configuration. This type has the
29361 @item @code{mumi} (default: @code{mumi})
29362 The Mumi package to use.
29364 @item @code{mailer?} (default: @code{#true})
29365 Whether to enable or disable the mailer component.
29367 @item @code{mumi-configuration-sender}
29368 The email address used as the sender for comments.
29370 @item @code{mumi-configuration-smtp}
29371 A URI to configure the SMTP settings for Mailutils. This could be
29372 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
29373 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
29374 mailutils, GNU@tie{}Mailutils}.
29380 @subsubheading FastCGI
29383 FastCGI is an interface between the front-end and the back-end of a web
29384 service. It is a somewhat legacy facility; new web services should
29385 generally just talk HTTP between the front-end and the back-end.
29386 However there are a number of back-end services such as PHP or the
29387 optimized HTTP Git repository access that use FastCGI, so we have
29388 support for it in Guix.
29390 To use FastCGI, you configure the front-end web server (e.g., nginx) to
29391 dispatch some subset of its requests to the fastcgi backend, which
29392 listens on a local TCP or UNIX socket. There is an intermediary
29393 @code{fcgiwrap} program that sits between the actual backend process and
29394 the web server. The front-end indicates which backend program to run,
29395 passing that information to the @code{fcgiwrap} process.
29397 @defvr {Scheme Variable} fcgiwrap-service-type
29398 A service type for the @code{fcgiwrap} FastCGI proxy.
29401 @deftp {Data Type} fcgiwrap-configuration
29402 Data type representing the configuration of the @code{fcgiwrap} service.
29403 This type has the following parameters:
29405 @item @code{package} (default: @code{fcgiwrap})
29406 The fcgiwrap package to use.
29408 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
29409 The socket on which the @code{fcgiwrap} process should listen, as a
29410 string. Valid @var{socket} values include
29411 @code{unix:@var{/path/to/unix/socket}},
29412 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
29413 @code{tcp6:[@var{ipv6_addr}]:port}.
29415 @item @code{user} (default: @code{fcgiwrap})
29416 @itemx @code{group} (default: @code{fcgiwrap})
29417 The user and group names, as strings, under which to run the
29418 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
29419 the user asks for the specific user or group names @code{fcgiwrap} that
29420 the corresponding user and/or group is present on the system.
29422 It is possible to configure a FastCGI-backed web service to pass HTTP
29423 authentication information from the front-end to the back-end, and to
29424 allow @code{fcgiwrap} to run the back-end process as a corresponding
29425 local user. To enable this capability on the back-end, run
29426 @code{fcgiwrap} as the @code{root} user and group. Note that this
29427 capability also has to be configured on the front-end as well.
29432 @subsubheading PHP-FPM
29434 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
29435 with some additional features useful for sites of any size.
29437 These features include:
29439 @item Adaptive process spawning
29440 @item Basic statistics (similar to Apache's mod_status)
29441 @item Advanced process management with graceful stop/start
29442 @item Ability to start workers with different uid/gid/chroot/environment
29443 and different php.ini (replaces safe_mode)
29444 @item Stdout & stderr logging
29445 @item Emergency restart in case of accidental opcode cache destruction
29446 @item Accelerated upload support
29447 @item Support for a "slowlog"
29448 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
29449 a special function to finish request & flush all data while continuing to do
29450 something time-consuming (video converting, stats processing, etc.)
29452 ...@: and much more.
29454 @defvr {Scheme Variable} php-fpm-service-type
29455 A Service type for @code{php-fpm}.
29458 @deftp {Data Type} php-fpm-configuration
29459 Data Type for php-fpm service configuration.
29461 @item @code{php} (default: @code{php})
29462 The php package to use.
29463 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
29464 The address on which to accept FastCGI requests. Valid syntaxes are:
29466 @item @code{"ip.add.re.ss:port"}
29467 Listen on a TCP socket to a specific address on a specific port.
29468 @item @code{"port"}
29469 Listen on a TCP socket to all addresses on a specific port.
29470 @item @code{"/path/to/unix/socket"}
29471 Listen on a unix socket.
29474 @item @code{user} (default: @code{php-fpm})
29475 User who will own the php worker processes.
29476 @item @code{group} (default: @code{php-fpm})
29477 Group of the worker processes.
29478 @item @code{socket-user} (default: @code{php-fpm})
29479 User who can speak to the php-fpm socket.
29480 @item @code{socket-group} (default: @code{nginx})
29481 Group that can speak to the php-fpm socket.
29482 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
29483 The process id of the php-fpm process is written to this file
29484 once the service has started.
29485 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
29486 Log for the php-fpm master process.
29487 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
29488 Detailed settings for the php-fpm process manager.
29491 @item @code{<php-fpm-dynamic-process-manager-configuration>}
29492 @item @code{<php-fpm-static-process-manager-configuration>}
29493 @item @code{<php-fpm-on-demand-process-manager-configuration>}
29495 @item @code{display-errors} (default @code{#f})
29496 Determines whether php errors and warning should be sent to clients
29497 and displayed in their browsers.
29498 This is useful for local php development, but a security risk for public sites,
29499 as error messages can reveal passwords and personal data.
29500 @item @code{timezone} (default @code{#f})
29501 Specifies @code{php_admin_value[date.timezone]} parameter.
29502 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
29503 This file will log the @code{stderr} outputs of php worker processes.
29504 Can be set to @code{#f} to disable logging.
29505 @item @code{file} (default @code{#f})
29506 An optional override of the whole configuration.
29507 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29508 @item @code{php-ini-file} (default @code{#f})
29509 An optional override of the default php settings.
29510 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
29511 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29513 For local development it is useful to set a higher timeout and memory
29514 limit for spawned php processes. This be accomplished with the
29515 following operating system configuration snippet:
29517 (define %local-php-ini
29518 (plain-file "php.ini"
29520 max_execution_time = 1800"))
29524 (services (cons (service php-fpm-service-type
29525 (php-fpm-configuration
29526 (php-ini-file %local-php-ini)))
29530 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
29531 directives} for comprehensive documentation on the acceptable
29532 @file{php.ini} directives.
29536 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
29537 Data Type for the @code{dynamic} php-fpm process manager. With the
29538 @code{dynamic} process manager, spare worker processes are kept around
29539 based on its configured limits.
29541 @item @code{max-children} (default: @code{5})
29542 Maximum of worker processes.
29543 @item @code{start-servers} (default: @code{2})
29544 How many worker processes should be started on start-up.
29545 @item @code{min-spare-servers} (default: @code{1})
29546 How many spare worker processes should be kept around at minimum.
29547 @item @code{max-spare-servers} (default: @code{3})
29548 How many spare worker processes should be kept around at maximum.
29552 @deftp {Data type} php-fpm-static-process-manager-configuration
29553 Data Type for the @code{static} php-fpm process manager. With the
29554 @code{static} process manager, an unchanging number of worker processes
29557 @item @code{max-children} (default: @code{5})
29558 Maximum of worker processes.
29562 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
29563 Data Type for the @code{on-demand} php-fpm process manager. With the
29564 @code{on-demand} process manager, worker processes are only created as
29567 @item @code{max-children} (default: @code{5})
29568 Maximum of worker processes.
29569 @item @code{process-idle-timeout} (default: @code{10})
29570 The time in seconds after which a process with no requests is killed.
29575 @deffn {Scheme Procedure} nginx-php-location @
29576 [#:nginx-package nginx] @
29577 [socket (string-append "/var/run/php" @
29578 (version-major (package-version php)) @
29580 A helper function to quickly add php to an @code{nginx-server-configuration}.
29583 A simple services setup for nginx with php can look like this:
29585 (services (cons* (service dhcp-client-service-type)
29586 (service php-fpm-service-type)
29587 (service nginx-service-type
29588 (nginx-server-configuration
29589 (server-name '("example.com"))
29590 (root "/srv/http/")
29592 (list (nginx-php-location)))
29594 (ssl-certificate #f)
29595 (ssl-certificate-key #f)))
29599 @cindex cat-avatar-generator
29600 The cat avatar generator is a simple service to demonstrate the use of php-fpm
29601 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
29602 the hash of a user's email address.
29604 @deffn {Scheme Procedure} cat-avatar-generator-service @
29605 [#:cache-dir "/var/cache/cat-avatar-generator"] @
29606 [#:package cat-avatar-generator] @
29607 [#:configuration (nginx-server-configuration)]
29608 Returns an nginx-server-configuration that inherits @code{configuration}. It
29609 extends the nginx configuration to add a server block that serves @code{package},
29610 a version of cat-avatar-generator. During execution, cat-avatar-generator will
29611 be able to use @code{cache-dir} as its cache directory.
29614 A simple setup for cat-avatar-generator can look like this:
29616 (services (cons* (cat-avatar-generator-service
29618 (nginx-server-configuration
29619 (server-name '("example.com"))))
29624 @subsubheading Hpcguix-web
29626 @cindex hpcguix-web
29627 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
29628 program is a customizable web interface to browse Guix packages,
29629 initially designed for users of high-performance computing (HPC)
29632 @defvr {Scheme Variable} hpcguix-web-service-type
29633 The service type for @code{hpcguix-web}.
29636 @deftp {Data Type} hpcguix-web-configuration
29637 Data type for the hpcguix-web service configuration.
29641 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
29642 configuration. The main items available in this spec are:
29645 @item @code{title-prefix} (default: @code{"hpcguix | "})
29646 The page title prefix.
29648 @item @code{guix-command} (default: @code{"guix"})
29649 The @command{guix} command.
29651 @item @code{package-filter-proc} (default: @code{(const #t)})
29652 A procedure specifying how to filter packages that are displayed.
29654 @item @code{package-page-extension-proc} (default: @code{(const '())})
29655 Extension package for @code{hpcguix-web}.
29657 @item @code{menu} (default: @code{'()})
29658 Additional entry in page @code{menu}.
29660 @item @code{channels} (default: @code{%default-channels})
29661 List of channels from which the package list is built (@pxref{Channels}).
29663 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
29664 The expiration time, in seconds, after which the package list is rebuilt from
29665 the latest instances of the given channels.
29668 See the hpcguix-web repository for a
29669 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
29672 @item @code{package} (default: @code{hpcguix-web})
29673 The hpcguix-web package to use.
29675 @item @code{address} (default: @code{"127.0.0.1"})
29676 The IP address to listen to.
29678 @item @code{port} (default: @code{5000})
29679 The port number to listen to.
29683 A typical hpcguix-web service declaration looks like this:
29686 (service hpcguix-web-service-type
29687 (hpcguix-web-configuration
29689 #~(define site-config
29690 (hpcweb-configuration
29691 (title-prefix "Guix-HPC - ")
29692 (menu '(("/about" "ABOUT"))))))))
29696 The hpcguix-web service periodically updates the package list it publishes by
29697 pulling channels from Git. To that end, it needs to access X.509 certificates
29698 so that it can authenticate Git servers when communicating over HTTPS, and it
29699 assumes that @file{/etc/ssl/certs} contains those certificates.
29701 Thus, make sure to add @code{nss-certs} or another certificate package to the
29702 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
29703 more information on X.509 certificates.
29706 @subsubheading gmnisrv
29709 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
29710 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
29712 @deffn {Scheme Variable} gmnisrv-service-type
29713 This is the type of the gmnisrv service, whose value should be a
29714 @code{gmnisrv-configuration} object, as in this example:
29717 (service gmnisrv-service-type
29718 (gmnisrv-configuration
29719 (config-file (local-file "./my-gmnisrv.ini"))))
29723 @deftp {Data Type} gmnisrv-configuration
29724 Data type representing the configuration of gmnisrv.
29727 @item @code{package} (default: @var{gmnisrv})
29728 Package object of the gmnisrv server.
29730 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
29731 File-like object of the gmnisrv configuration file to use. The default
29732 configuration listens on port 1965 and serves files from
29733 @file{/srv/gemini}. Certificates are stored in
29734 @file{/var/lib/gemini/certs}. For more information, run @command{man
29735 gmnisrv} and @command{man gmnisrv.ini}.
29740 @subsubheading Agate
29743 The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
29744 (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
29745 program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
29746 protocol server written in Rust.
29748 @deffn {Scheme Variable} agate-service-type
29749 This is the type of the agate service, whose value should be an
29750 @code{agate-service-type} object, as in this example:
29753 (service agate-service-type
29754 (agate-configuration
29755 (content "/srv/gemini")
29756 (cert "/srv/cert.pem")
29757 (key "/srv/key.rsa")))
29760 The example above represents the minimal tweaking necessary to get Agate
29761 up and running. Specifying the path to the certificate and key is
29762 always necessary, as the Gemini protocol requires TLS by default.
29764 To obtain a certificate and a key, you could, for example, use OpenSSL,
29765 running a command similar to the following example:
29768 openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
29769 -days 3650 -nodes -subj "/CN=example.com"
29772 Of course, you'll have to replace @i{example.com} with your own domain
29773 name, and then point the Agate configuration towards the path of the
29774 generated key and certificate.
29778 @deftp {Data Type} agate-configuration
29779 Data type representing the configuration of Agate.
29782 @item @code{package} (default: @code{agate})
29783 The package object of the Agate server.
29785 @item @code{content} (default: @file{"/srv/gemini"})
29786 The directory from which Agate will serve files.
29788 @item @code{cert} (default: @code{#f})
29789 The path to the TLS certificate PEM file to be used for encrypted
29790 connections. Must be filled in with a value from the user.
29792 @item @code{key} (default: @code{#f})
29793 The path to the PKCS8 private key file to be used for encrypted
29794 connections. Must be filled in with a value from the user.
29796 @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
29797 A list of the addresses to listen on.
29799 @item @code{hostname} (default: @code{#f})
29800 The domain name of this Gemini server. Optional.
29802 @item @code{lang} (default: @code{#f})
29803 RFC 4646 language code(s) for text/gemini documents. Optional.
29805 @item @code{silent?} (default: @code{#f})
29806 Set to @code{#t} to disable logging output.
29808 @item @code{serve-secret?} (default: @code{#f})
29809 Set to @code{#t} to serve secret files (files/directories starting with
29812 @item @code{log-ip?} (default: @code{#t})
29813 Whether or not to output IP addresses when logging.
29815 @item @code{user} (default: @code{"agate"})
29816 Owner of the @code{agate} process.
29818 @item @code{group} (default: @code{"agate"})
29819 Owner's group of the @code{agate} process.
29821 @item @code{log-file} (default: @file{"/var/log/agate.log"})
29822 The file which should store the logging output of Agate.
29827 @node Certificate Services
29828 @subsection Certificate Services
29831 @cindex HTTP, HTTPS
29832 @cindex Let's Encrypt
29833 @cindex TLS certificates
29834 The @code{(gnu services certbot)} module provides a service to
29835 automatically obtain a valid TLS certificate from the Let's Encrypt
29836 certificate authority. These certificates can then be used to serve
29837 content securely over HTTPS or other TLS-based protocols, with the
29838 knowledge that the client will be able to verify the server's
29841 @url{https://letsencrypt.org/, Let's Encrypt} provides the
29842 @code{certbot} tool to automate the certification process. This tool
29843 first securely generates a key on the server. It then makes a request
29844 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
29845 checks that the request originates from the host in question by using a
29846 challenge-response protocol, requiring the server to provide its
29847 response over HTTP@. If that protocol completes successfully, the CA
29848 signs the key, resulting in a certificate. That certificate is valid
29849 for a limited period of time, and therefore to continue to provide TLS
29850 services, the server needs to periodically ask the CA to renew its
29853 The certbot service automates this process: the initial key
29854 generation, the initial certification request to the Let's Encrypt
29855 service, the web server challenge/response integration, writing the
29856 certificate to disk, the automated periodic renewals, and the deployment
29857 tasks associated with the renewal (e.g.@: reloading services, copying keys
29858 with different permissions).
29860 Certbot is run twice a day, at a random minute within the hour. It
29861 won't do anything until your certificates are due for renewal or
29862 revoked, but running it regularly would give your service a chance of
29863 staying online in case a Let's Encrypt-initiated revocation happened for
29866 By using this service, you agree to the ACME Subscriber Agreement, which
29867 can be found there:
29868 @url{https://acme-v01.api.letsencrypt.org/directory}.
29870 @defvr {Scheme Variable} certbot-service-type
29871 A service type for the @code{certbot} Let's Encrypt client. Its value
29872 must be a @code{certbot-configuration} record as in this example:
29875 (define %nginx-deploy-hook
29877 "nginx-deploy-hook"
29878 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
29879 (kill pid SIGHUP))))
29881 (service certbot-service-type
29882 (certbot-configuration
29883 (email "foo@@example.net")
29886 (certificate-configuration
29887 (domains '("example.net" "www.example.net"))
29888 (deploy-hook %nginx-deploy-hook))
29889 (certificate-configuration
29890 (domains '("bar.example.net")))))))
29893 See below for details about @code{certbot-configuration}.
29896 @deftp {Data Type} certbot-configuration
29897 Data type representing the configuration of the @code{certbot} service.
29898 This type has the following parameters:
29901 @item @code{package} (default: @code{certbot})
29902 The certbot package to use.
29904 @item @code{webroot} (default: @code{/var/www})
29905 The directory from which to serve the Let's Encrypt challenge/response
29908 @item @code{certificates} (default: @code{()})
29909 A list of @code{certificates-configuration}s for which to generate
29910 certificates and request signatures. Each certificate has a @code{name}
29911 and several @code{domains}.
29913 @item @code{email} (default: @code{#f})
29914 Optional email address used for registration and recovery contact.
29915 Setting this is encouraged as it allows you to receive important
29916 notifications about the account and issued certificates.
29918 @item @code{server} (default: @code{#f})
29919 Optional URL of ACME server. Setting this overrides certbot's default,
29920 which is the Let's Encrypt server.
29922 @item @code{rsa-key-size} (default: @code{2048})
29923 Size of the RSA key.
29925 @item @code{default-location} (default: @i{see below})
29926 The default @code{nginx-location-configuration}. Because @code{certbot}
29927 needs to be able to serve challenges and responses, it needs to be able
29928 to run a web server. It does so by extending the @code{nginx} web
29929 service with an @code{nginx-server-configuration} listening on the
29930 @var{domains} on port 80, and which has a
29931 @code{nginx-location-configuration} for the @code{/.well-known/} URI
29932 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
29933 these nginx configuration data types.
29935 Requests to other URL paths will be matched by the
29936 @code{default-location}, which if present is added to all
29937 @code{nginx-server-configuration}s.
29939 By default, the @code{default-location} will issue a redirect from
29940 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
29941 you to define what to serve on your site via @code{https}.
29943 Pass @code{#f} to not issue a default location.
29947 @deftp {Data Type} certificate-configuration
29948 Data type representing the configuration of a certificate.
29949 This type has the following parameters:
29952 @item @code{name} (default: @i{see below})
29953 This name is used by Certbot for housekeeping and in file paths; it
29954 doesn't affect the content of the certificate itself. To see
29955 certificate names, run @code{certbot certificates}.
29957 Its default is the first provided domain.
29959 @item @code{domains} (default: @code{()})
29960 The first domain provided will be the subject CN of the certificate, and
29961 all domains will be Subject Alternative Names on the certificate.
29963 @item @code{challenge} (default: @code{#f})
29964 The challenge type that has to be run by certbot. If @code{#f} is specified,
29965 default to the HTTP challenge. If a value is specified, defaults to the
29966 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
29967 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
29968 and gives Let's Encrypt permission to log the public IP address of the
29969 requesting machine.
29971 @item @code{csr} (default: @code{#f})
29972 File name of Certificate Signing Request (CSR) in DER or PEM format.
29973 If @code{#f} is specified, this argument will not be passed to certbot.
29974 If a value is specified, certbot will use it to obtain a certificate, instead of
29975 using a self-generated CSR.
29976 The domain-name(s) mentioned in @code{domains}, must be consistent with the
29977 domain-name(s) mentioned in CSR file.
29979 @item @code{authentication-hook} (default: @code{#f})
29980 Command to be run in a shell once for each certificate challenge to be
29981 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
29982 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
29983 contains the validation string and @code{$CERTBOT_TOKEN} contains the
29984 file name of the resource requested when performing an HTTP-01 challenge.
29986 @item @code{cleanup-hook} (default: @code{#f})
29987 Command to be run in a shell once for each certificate challenge that
29988 have been answered by the @code{auth-hook}. For this command, the shell
29989 variables available in the @code{auth-hook} script are still available, and
29990 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
29991 of the @code{auth-hook} script.
29993 @item @code{deploy-hook} (default: @code{#f})
29994 Command to be run in a shell once for each successfully issued
29995 certificate. For this command, the shell variable
29996 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
29997 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
29998 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
29999 contain a space-delimited list of renewed certificate domains (for
30000 example, @samp{"example.com www.example.com"}.
30005 For each @code{certificate-configuration}, the certificate is saved to
30006 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
30007 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
30009 @subsection DNS Services
30010 @cindex DNS (domain name system)
30011 @cindex domain name system (DNS)
30013 The @code{(gnu services dns)} module provides services related to the
30014 @dfn{domain name system} (DNS). It provides a server service for hosting
30015 an @emph{authoritative} DNS server for multiple zones, slave or master.
30016 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
30017 caching and forwarding DNS server for the LAN, which uses
30018 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
30020 @subsubheading Knot Service
30022 An example configuration of an authoritative server for two zones, one master
30026 (define-zone-entries example.org.zone
30027 ;; Name TTL Class Type Data
30028 ("@@" "" "IN" "A" "127.0.0.1")
30029 ("@@" "" "IN" "NS" "ns")
30030 ("ns" "" "IN" "A" "127.0.0.1"))
30032 (define master-zone
30033 (knot-zone-configuration
30034 (domain "example.org")
30036 (origin "example.org")
30037 (entries example.org.zone)))))
30040 (knot-zone-configuration
30041 (domain "plop.org")
30042 (dnssec-policy "default")
30043 (master (list "plop-master"))))
30045 (define plop-master
30046 (knot-remote-configuration
30048 (address (list "208.76.58.171"))))
30052 (services (cons* (service knot-service-type
30053 (knot-configuration
30054 (remotes (list plop-master))
30055 (zones (list master-zone slave-zone))))
30060 @deffn {Scheme Variable} knot-service-type
30061 This is the type for the Knot DNS server.
30063 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
30064 zones, that is to say domain names you would buy from a registrar. This server
30065 is not a resolver, meaning that it can only resolve names for which it is
30066 authoritative. This server can be configured to serve zones as a master server
30067 or a slave server as a per-zone basis. Slave zones will get their data from
30068 masters, and will serve it as an authoritative server. From the point of view
30069 of a resolver, there is no difference between master and slave.
30071 The following data types are used to configure the Knot DNS server:
30074 @deftp {Data Type} knot-key-configuration
30075 Data type representing a key.
30076 This type has the following parameters:
30079 @item @code{id} (default: @code{""})
30080 An identifier for other configuration fields to refer to this key. IDs must
30081 be unique and must not be empty.
30083 @item @code{algorithm} (default: @code{#f})
30084 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
30085 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
30086 and @code{'hmac-sha512}.
30088 @item @code{secret} (default: @code{""})
30089 The secret key itself.
30094 @deftp {Data Type} knot-acl-configuration
30095 Data type representing an Access Control List (ACL) configuration.
30096 This type has the following parameters:
30099 @item @code{id} (default: @code{""})
30100 An identifier for other configuration fields to refer to this key. IDs must be
30101 unique and must not be empty.
30103 @item @code{address} (default: @code{'()})
30104 An ordered list of IP addresses, network subnets, or network ranges represented
30105 with strings. The query must match one of them. Empty value means that
30106 address match is not required.
30108 @item @code{key} (default: @code{'()})
30109 An ordered list of references to keys represented with strings. The string
30110 must match a key ID defined in a @code{knot-key-configuration}. No key means
30111 that a key is not require to match that ACL.
30113 @item @code{action} (default: @code{'()})
30114 An ordered list of actions that are permitted or forbidden by this ACL@. Possible
30115 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
30116 and @code{'update}.
30118 @item @code{deny?} (default: @code{#f})
30119 When true, the ACL defines restrictions. Listed actions are forbidden. When
30120 false, listed actions are allowed.
30125 @deftp {Data Type} zone-entry
30126 Data type representing a record entry in a zone file.
30127 This type has the following parameters:
30130 @item @code{name} (default: @code{"@@"})
30131 The name of the record. @code{"@@"} refers to the origin of the zone. Names
30132 are relative to the origin of the zone. For example, in the @code{example.org}
30133 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
30134 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
30135 refers to @code{ns.example.org}.
30137 @item @code{ttl} (default: @code{""})
30138 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
30140 @item @code{class} (default: @code{"IN"})
30141 The class of the record. Knot currently supports only @code{"IN"} and
30142 partially @code{"CH"}.
30144 @item @code{type} (default: @code{"A"})
30145 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
30146 address), NS (Name Server) and MX (Mail eXchange). Many other types are
30149 @item @code{data} (default: @code{""})
30150 The data contained in the record. For instance an IP address associated with
30151 an A record, or a domain name associated with an NS record. Remember that
30152 domain names are relative to the origin unless they end with a dot.
30157 @deftp {Data Type} zone-file
30158 Data type representing the content of a zone file.
30159 This type has the following parameters:
30162 @item @code{entries} (default: @code{'()})
30163 The list of entries. The SOA record is taken care of, so you don't need to
30164 put it in the list of entries. This list should probably contain an entry
30165 for your primary authoritative DNS server. Other than using a list of entries
30166 directly, you can use @code{define-zone-entries} to define a object containing
30167 the list of entries more easily, that you can later pass to the @code{entries}
30168 field of the @code{zone-file}.
30170 @item @code{origin} (default: @code{""})
30171 The name of your zone. This parameter cannot be empty.
30173 @item @code{ns} (default: @code{"ns"})
30174 The domain of your primary authoritative DNS server. The name is relative to
30175 the origin, unless it ends with a dot. It is mandatory that this primary
30176 DNS server corresponds to an NS record in the zone and that it is associated
30177 to an IP address in the list of entries.
30179 @item @code{mail} (default: @code{"hostmaster"})
30180 An email address people can contact you at, as the owner of the zone. This
30181 is translated as @code{<mail>@@<origin>}.
30183 @item @code{serial} (default: @code{1})
30184 The serial number of the zone. As this is used to keep track of changes by
30185 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
30186 Always increment it when you make a change in your zone.
30188 @item @code{refresh} (default: @code{(* 2 24 3600)})
30189 The frequency at which slaves will do a zone transfer. This value is a number
30190 of seconds. It can be computed by multiplications or with
30191 @code{(string->duration)}.
30193 @item @code{retry} (default: @code{(* 15 60)})
30194 The period after which a slave will retry to contact its master when it fails
30195 to do so a first time.
30197 @item @code{expiry} (default: @code{(* 14 24 3600)})
30198 Default TTL of records. Existing records are considered correct for at most
30199 this amount of time. After this period, resolvers will invalidate their cache
30200 and check again that it still exists.
30202 @item @code{nx} (default: @code{3600})
30203 Default TTL of inexistent records. This delay is usually short because you want
30204 your new domains to reach everyone quickly.
30209 @deftp {Data Type} knot-remote-configuration
30210 Data type representing a remote configuration.
30211 This type has the following parameters:
30214 @item @code{id} (default: @code{""})
30215 An identifier for other configuration fields to refer to this remote. IDs must
30216 be unique and must not be empty.
30218 @item @code{address} (default: @code{'()})
30219 An ordered list of destination IP addresses. Addresses are tried in sequence.
30220 An optional port can be given with the @@ separator. For instance:
30221 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
30223 @item @code{via} (default: @code{'()})
30224 An ordered list of source IP addresses. An empty list will have Knot choose
30225 an appropriate source IP@. An optional port can be given with the @@ separator.
30226 The default is to choose at random.
30228 @item @code{key} (default: @code{#f})
30229 A reference to a key, that is a string containing the identifier of a key
30230 defined in a @code{knot-key-configuration} field.
30235 @deftp {Data Type} knot-keystore-configuration
30236 Data type representing a keystore to hold dnssec keys.
30237 This type has the following parameters:
30240 @item @code{id} (default: @code{""})
30241 The id of the keystore. It must not be empty.
30243 @item @code{backend} (default: @code{'pem})
30244 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
30246 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
30247 The configuration string of the backend. An example for the PKCS#11 is:
30248 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
30249 For the pem backend, the string represents a path in the file system.
30254 @deftp {Data Type} knot-policy-configuration
30255 Data type representing a dnssec policy. Knot DNS is able to automatically
30256 sign your zones. It can either generate and manage your keys automatically or
30257 use keys that you generate.
30259 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
30260 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
30261 zone. In order to be trusted, the KSK needs to be present in the parent zone
30262 (usually a top-level domain). If your registrar supports dnssec, you will
30263 have to send them your KSK's hash so they can add a DS record in their zone.
30264 This is not automated and need to be done each time you change your KSK.
30266 The policy also defines the lifetime of keys. Usually, ZSK can be changed
30267 easily and use weaker cryptographic functions (they use lower parameters) in
30268 order to sign records quickly, so they are changed often. The KSK however
30269 requires manual interaction with the registrar, so they are changed less often
30270 and use stronger parameters because they sign only one record.
30272 This type has the following parameters:
30275 @item @code{id} (default: @code{""})
30276 The id of the policy. It must not be empty.
30278 @item @code{keystore} (default: @code{"default"})
30279 A reference to a keystore, that is a string containing the identifier of a
30280 keystore defined in a @code{knot-keystore-configuration} field. The
30281 @code{"default"} identifier means the default keystore (a kasp database that
30282 was setup by this service).
30284 @item @code{manual?} (default: @code{#f})
30285 Whether the key management is manual or automatic.
30287 @item @code{single-type-signing?} (default: @code{#f})
30288 When @code{#t}, use the Single-Type Signing Scheme.
30290 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
30291 An algorithm of signing keys and issued signatures.
30293 @item @code{ksk-size} (default: @code{256})
30294 The length of the KSK@. Note that this value is correct for the default
30295 algorithm, but would be unsecure for other algorithms.
30297 @item @code{zsk-size} (default: @code{256})
30298 The length of the ZSK@. Note that this value is correct for the default
30299 algorithm, but would be unsecure for other algorithms.
30301 @item @code{dnskey-ttl} (default: @code{'default})
30302 The TTL value for DNSKEY records added into zone apex. The special
30303 @code{'default} value means same as the zone SOA TTL.
30305 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
30306 The period between ZSK publication and the next rollover initiation.
30308 @item @code{propagation-delay} (default: @code{(* 24 3600)})
30309 An extra delay added for each key rollover step. This value should be high
30310 enough to cover propagation of data from the master server to all slaves.
30312 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
30313 A validity period of newly issued signatures.
30315 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
30316 A period how long before a signature expiration the signature will be refreshed.
30318 @item @code{nsec3?} (default: @code{#f})
30319 When @code{#t}, NSEC3 will be used instead of NSEC.
30321 @item @code{nsec3-iterations} (default: @code{5})
30322 The number of additional times the hashing is performed.
30324 @item @code{nsec3-salt-length} (default: @code{8})
30325 The length of a salt field in octets, which is appended to the original owner
30326 name before hashing.
30328 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
30329 The validity period of newly issued salt field.
30334 @deftp {Data Type} knot-zone-configuration
30335 Data type representing a zone served by Knot.
30336 This type has the following parameters:
30339 @item @code{domain} (default: @code{""})
30340 The domain served by this configuration. It must not be empty.
30342 @item @code{file} (default: @code{""})
30343 The file where this zone is saved. This parameter is ignored by master zones.
30344 Empty means default location that depends on the domain name.
30346 @item @code{zone} (default: @code{(zone-file)})
30347 The content of the zone file. This parameter is ignored by slave zones. It
30348 must contain a zone-file record.
30350 @item @code{master} (default: @code{'()})
30351 A list of master remotes. When empty, this zone is a master. When set, this
30352 zone is a slave. This is a list of remotes identifiers.
30354 @item @code{ddns-master} (default: @code{#f})
30355 The main master. When empty, it defaults to the first master in the list of
30358 @item @code{notify} (default: @code{'()})
30359 A list of slave remote identifiers.
30361 @item @code{acl} (default: @code{'()})
30362 A list of acl identifiers.
30364 @item @code{semantic-checks?} (default: @code{#f})
30365 When set, this adds more semantic checks to the zone.
30367 @item @code{zonefile-sync} (default: @code{0})
30368 The delay between a modification in memory and on disk. 0 means immediate
30371 @item @code{zonefile-load} (default: @code{#f})
30372 The way the zone file contents are applied during zone load. Possible values
30376 @item @code{#f} for using the default value from Knot,
30377 @item @code{'none} for not using the zone file at all,
30378 @item @code{'difference} for computing the difference between already available
30379 contents and zone contents and applying it to the current zone contents,
30380 @item @code{'difference-no-serial} for the same as @code{'difference}, but
30381 ignoring the SOA serial in the zone file, while the server takes care of it
30383 @item @code{'whole} for loading zone contents from the zone file.
30386 @item @code{journal-content} (default: @code{#f})
30387 The way the journal is used to store zone and its changes. Possible values
30388 are @code{'none} to not use it at all, @code{'changes} to store changes and
30389 @code{'all} to store contents. @code{#f} does not set this option, so the
30390 default value from Knot is used.
30392 @item @code{max-journal-usage} (default: @code{#f})
30393 The maximum size for the journal on disk. @code{#f} does not set this option,
30394 so the default value from Knot is used.
30396 @item @code{max-journal-depth} (default: @code{#f})
30397 The maximum size of the history. @code{#f} does not set this option, so the
30398 default value from Knot is used.
30400 @item @code{max-zone-size} (default: @code{#f})
30401 The maximum size of the zone file. This limit is enforced for incoming
30402 transfer and updates. @code{#f} does not set this option, so the default
30403 value from Knot is used.
30405 @item @code{dnssec-policy} (default: @code{#f})
30406 A reference to a @code{knot-policy-configuration} record, or the special
30407 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
30410 @item @code{serial-policy} (default: @code{'increment})
30411 A policy between @code{'increment} and @code{'unixtime}.
30416 @deftp {Data Type} knot-configuration
30417 Data type representing the Knot configuration.
30418 This type has the following parameters:
30421 @item @code{knot} (default: @code{knot})
30424 @item @code{run-directory} (default: @code{"/var/run/knot"})
30425 The run directory. This directory will be used for pid file and sockets.
30427 @item @code{includes} (default: @code{'()})
30428 A list of strings or file-like objects denoting other files that must be
30429 included at the top of the configuration file.
30431 @cindex secrets, Knot service
30432 This can be used to manage secrets out-of-band. For example, secret
30433 keys may be stored in an out-of-band file not managed by Guix, and
30434 thus not visible in @file{/gnu/store}---e.g., you could store secret
30435 key configuration in @file{/etc/knot/secrets.conf} and add this file
30436 to the @code{includes} list.
30438 One can generate a secret tsig key (for nsupdate and zone transfers with the
30439 keymgr command from the knot package. Note that the package is not automatically
30440 installed by the service. The following example shows how to generate a new
30444 keymgr -t mysecret > /etc/knot/secrets.conf
30445 chmod 600 /etc/knot/secrets.conf
30448 Also note that the generated key will be named @var{mysecret}, so it is the
30449 name that needs to be used in the @var{key} field of the
30450 @code{knot-acl-configuration} record and in other places that need to refer
30453 It can also be used to add configuration not supported by this interface.
30455 @item @code{listen-v4} (default: @code{"0.0.0.0"})
30456 An ip address on which to listen.
30458 @item @code{listen-v6} (default: @code{"::"})
30459 An ip address on which to listen.
30461 @item @code{listen-port} (default: @code{53})
30462 A port on which to listen.
30464 @item @code{keys} (default: @code{'()})
30465 The list of knot-key-configuration used by this configuration.
30467 @item @code{acls} (default: @code{'()})
30468 The list of knot-acl-configuration used by this configuration.
30470 @item @code{remotes} (default: @code{'()})
30471 The list of knot-remote-configuration used by this configuration.
30473 @item @code{zones} (default: @code{'()})
30474 The list of knot-zone-configuration used by this configuration.
30479 @subsubheading Knot Resolver Service
30481 @deffn {Scheme Variable} knot-resolver-service-type
30482 This is the type of the knot resolver service, whose value should be
30483 an @code{knot-resolver-configuration} object as in this example:
30486 (service knot-resolver-service-type
30487 (knot-resolver-configuration
30488 (kresd-config-file (plain-file "kresd.conf" "
30489 net.listen('192.168.0.1', 5353)
30490 user('knot-resolver', 'knot-resolver')
30491 modules = @{ 'hints > iterate', 'stats', 'predict' @}
30492 cache.size = 100 * MB
30496 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
30499 @deftp {Data Type} knot-resolver-configuration
30500 Data type representing the configuration of knot-resolver.
30503 @item @code{package} (default: @var{knot-resolver})
30504 Package object of the knot DNS resolver.
30506 @item @code{kresd-config-file} (default: %kresd.conf)
30507 File-like object of the kresd configuration file to use, by default it
30508 will listen on @code{127.0.0.1} and @code{::1}.
30510 @item @code{garbage-collection-interval} (default: 1000)
30511 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
30517 @subsubheading Dnsmasq Service
30519 @deffn {Scheme Variable} dnsmasq-service-type
30520 This is the type of the dnsmasq service, whose value should be an
30521 @code{dnsmasq-configuration} object as in this example:
30524 (service dnsmasq-service-type
30525 (dnsmasq-configuration
30527 (servers '("192.168.1.1"))))
30531 @deftp {Data Type} dnsmasq-configuration
30532 Data type representing the configuration of dnsmasq.
30535 @item @code{package} (default: @var{dnsmasq})
30536 Package object of the dnsmasq server.
30538 @item @code{no-hosts?} (default: @code{#f})
30539 When true, don't read the hostnames in /etc/hosts.
30541 @item @code{port} (default: @code{53})
30542 The port to listen on. Setting this to zero completely disables DNS
30543 responses, leaving only DHCP and/or TFTP functions.
30545 @item @code{local-service?} (default: @code{#t})
30546 Accept DNS queries only from hosts whose address is on a local subnet,
30547 ie a subnet for which an interface exists on the server.
30549 @item @code{listen-addresses} (default: @code{'()})
30550 Listen on the given IP addresses.
30552 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
30553 The file to read the IP address of the upstream nameservers from.
30555 @item @code{no-resolv?} (default: @code{#f})
30556 When true, don't read @var{resolv-file}.
30558 @item @code{forward-private-reverse-lookup?} (default: @code{#t})
30559 When false, all reverse lookups for private IP ranges are answered with
30560 "no such domain" rather than being forwarded upstream.
30562 @item @code{query-servers-in-order?} (default: @code{#f})
30563 When true, dnsmasq queries the servers in the same order as they appear
30566 @item @code{servers} (default: @code{'()})
30567 Specify IP address of upstream servers directly.
30569 @item @code{addresses} (default: @code{'()})
30570 For each entry, specify an IP address to return for any host in the
30571 given domains. Queries in the domains are never forwarded and always
30572 replied to with the specified IP address.
30574 This is useful for redirecting hosts locally, for example:
30577 (service dnsmasq-service-type
30578 (dnsmasq-configuration
30580 '(; Redirect to a local web-server.
30581 "/example.org/127.0.0.1"
30582 ; Redirect subdomain to a specific IP.
30583 "/subdomain.example.org/192.168.1.42"))))
30586 Note that rules in @file{/etc/hosts} take precedence over this.
30588 @item @code{cache-size} (default: @code{150})
30589 Set the size of dnsmasq's cache. Setting the cache size to zero
30592 @item @code{negative-cache?} (default: @code{#t})
30593 When false, disable negative caching.
30595 @item @code{cpe-id} (default: @code{#f})
30596 If set, add a CPE (Customer-Premises Equipment) identifier to DNS
30597 queries which are forwarded upstream.
30599 @item @code{tftp-enable?} (default: @code{#f})
30600 Whether to enable the built-in TFTP server.
30602 @item @code{tftp-no-fail?} (default: @code{#f})
30603 If true, does not fail dnsmasq if the TFTP server could not start up.
30605 @item @code{tftp-single-port?} (default: @code{#f})
30606 Whether to use only one single port for TFTP.
30608 @item @code{tftp-secure?} (default: @code{#f})
30609 If true, only files owned by the user running the dnsmasq process are accessible.
30611 If dnsmasq is being run as root, different rules apply:
30612 @code{tftp-secure?} has no effect, but only files which have the
30613 world-readable bit set are accessible.
30615 @item @code{tftp-max} (default: @code{#f})
30616 If set, sets the maximal number of concurrent connections allowed.
30618 @item @code{tftp-mtu} (default: @code{#f})
30619 If set, sets the MTU for TFTP packets to that value.
30621 @item @code{tftp-no-blocksize?} (default: @code{#f})
30622 If true, stops the TFTP server from negotiating the blocksize with a client.
30624 @item @code{tftp-lowercase?} (default: @code{#f})
30625 Whether to convert all filenames in TFTP requests to lowercase.
30627 @item @code{tftp-port-range} (default: @code{#f})
30628 If set, fixes the dynamical ports (one per client) to the given range
30629 (@code{"<start>,<end>"}).
30631 @item @code{tftp-root} (default: @code{/var/empty,lo})
30632 Look for files to transfer using TFTP relative to the given directory.
30633 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
30634 getting outside the specified root. Absolute paths (starting with @samp{/}) are
30635 allowed, but they must be within the TFTP-root. If the optional interface
30636 argument is given, the directory is only used for TFTP requests via that
30639 @item @code{tftp-unique-root} (default: @code{#f})
30640 If set, add the IP or hardware address of the TFTP client as a path component
30641 on the end of the TFTP-root. Only valid if a TFTP root is set and the
30642 directory exists. Defaults to adding IP address (in standard dotted-quad
30645 For instance, if @option{--tftp-root} is @samp{/tftp} and client
30646 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
30647 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
30648 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
30649 append the MAC address instead, using lowercase zero padded digits
30650 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
30651 resolving MAC addresses is only possible if the client is in the local
30652 network or obtained a DHCP lease from dnsmasq.
30657 @subsubheading ddclient Service
30660 The ddclient service described below runs the ddclient daemon, which takes
30661 care of automatically updating DNS entries for service providers such as
30662 @uref{https://dyn.com/dns/, Dyn}.
30664 The following example show instantiates the service with its default
30668 (service ddclient-service-type)
30671 Note that ddclient needs to access credentials that are stored in a
30672 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
30673 @code{secret-file} below). You are expected to create this file manually, in
30674 an ``out-of-band'' fashion (you @emph{could} make this file part of the
30675 service configuration, for instance by using @code{plain-file}, but it will be
30676 world-readable @i{via} @file{/gnu/store}). See the examples in the
30677 @file{share/ddclient} directory of the @code{ddclient} package.
30679 @c %start of fragment
30681 Available @code{ddclient-configuration} fields are:
30683 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
30684 The ddclient package.
30688 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
30689 The period after which ddclient will retry to check IP and domain name.
30691 Defaults to @samp{300}.
30695 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
30696 Use syslog for the output.
30698 Defaults to @samp{#t}.
30702 @deftypevr {@code{ddclient-configuration} parameter} string mail
30705 Defaults to @samp{"root"}.
30709 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
30710 Mail failed update to user.
30712 Defaults to @samp{"root"}.
30716 @deftypevr {@code{ddclient-configuration} parameter} string pid
30717 The ddclient PID file.
30719 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
30723 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
30724 Enable SSL support.
30726 Defaults to @samp{#t}.
30730 @deftypevr {@code{ddclient-configuration} parameter} string user
30731 Specifies the user name or ID that is used when running ddclient
30734 Defaults to @samp{"ddclient"}.
30738 @deftypevr {@code{ddclient-configuration} parameter} string group
30739 Group of the user who will run the ddclient program.
30741 Defaults to @samp{"ddclient"}.
30745 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
30746 Secret file which will be appended to @file{ddclient.conf} file. This
30747 file contains credentials for use by ddclient. You are expected to
30748 create it manually.
30750 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
30754 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
30755 Extra options will be appended to @file{ddclient.conf} file.
30757 Defaults to @samp{()}.
30762 @c %end of fragment
30766 @subsection VPN Services
30767 @cindex VPN (virtual private network)
30768 @cindex virtual private network (VPN)
30770 The @code{(gnu services vpn)} module provides services related to
30771 @dfn{virtual private networks} (VPNs).
30773 @subsubheading Bitmask
30775 @defvr {Scheme Variable} bitmask-service-type
30776 A service type for the @uref{https://bitmask.net, Bitmask} VPN client. It makes
30777 the client available in the system and loads its polkit policy. Please note that
30778 the client expects an active polkit-agent, which is either run by your
30779 desktop-environment or should be run manually.
30782 @subsubheading OpenVPN
30784 It provides a @emph{client} service for your machine to connect to a
30785 VPN, and a @emph{server} service for your machine to host a VPN@.
30787 @deffn {Scheme Procedure} openvpn-client-service @
30788 [#:config (openvpn-client-configuration)]
30790 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
30793 @deffn {Scheme Procedure} openvpn-server-service @
30794 [#:config (openvpn-server-configuration)]
30796 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
30798 Both can be run simultaneously.
30801 @c %automatically generated documentation
30803 @deftp {Data Type} openvpn-client-configuration
30804 Available @code{openvpn-client-configuration} fields are:
30807 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30808 The OpenVPN package.
30810 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30811 The OpenVPN pid file.
30813 @item @code{proto} (default: @code{udp}) (type: proto)
30814 The protocol (UDP or TCP) used to open a channel between clients and
30817 @item @code{dev} (default: @code{tun}) (type: dev)
30818 The device type used to represent the VPN connection.
30820 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30821 The certificate authority to check connections against.
30823 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30824 The certificate of the machine the daemon is running on. It should be
30825 signed by the authority given in @code{ca}.
30827 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30828 The key of the machine the daemon is running on. It must be the key
30829 whose certificate is @code{cert}.
30831 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30832 Whether to use the lzo compression algorithm.
30834 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30835 Don't re-read key files across SIGUSR1 or --ping-restart.
30837 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30838 Don't close and reopen TUN/TAP device or run up/down scripts across
30839 SIGUSR1 or --ping-restart restarts.
30841 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30842 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30843 poll/epoll/select prior to the write operation.
30845 @item @code{verbosity} (default: @code{3}) (type: number)
30848 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-client)
30849 Add an additional layer of HMAC authentication on top of the TLS control
30850 channel to protect against DoS attacks.
30852 @item @code{auth-user-pass} (type: maybe-string)
30853 Authenticate with server using username/password. The option is a file
30854 containing username/password on 2 lines. Do not use a file-like object
30855 as it would be added to the store and readable by any user.
30857 @item @code{verify-key-usage?} (default: @code{#t}) (type: key-usage)
30858 Whether to check the server certificate has server usage extension.
30860 @item @code{bind?} (default: @code{#f}) (type: bind)
30861 Bind to a specific local port number.
30863 @item @code{resolv-retry?} (default: @code{#t}) (type: resolv-retry)
30864 Retry resolving server address.
30866 @item @code{remote} (default: @code{()}) (type: openvpn-remote-list)
30867 A list of remote servers to connect to.
30869 @deftp {Data Type} openvpn-remote-configuration
30870 Available @code{openvpn-remote-configuration} fields are:
30873 @item @code{name} (default: @code{"my-server"}) (type: string)
30876 @item @code{port} (default: @code{1194}) (type: number)
30877 Port number the server listens to.
30887 @c %end of automatic openvpn-client documentation
30889 @c %automatically generated documentation
30891 @deftp {Data Type} openvpn-server-configuration
30892 Available @code{openvpn-server-configuration} fields are:
30895 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30896 The OpenVPN package.
30898 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30899 The OpenVPN pid file.
30901 @item @code{proto} (default: @code{udp}) (type: proto)
30902 The protocol (UDP or TCP) used to open a channel between clients and
30905 @item @code{dev} (default: @code{tun}) (type: dev)
30906 The device type used to represent the VPN connection.
30908 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30909 The certificate authority to check connections against.
30911 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30912 The certificate of the machine the daemon is running on. It should be
30913 signed by the authority given in @code{ca}.
30915 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30916 The key of the machine the daemon is running on. It must be the key
30917 whose certificate is @code{cert}.
30919 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30920 Whether to use the lzo compression algorithm.
30922 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30923 Don't re-read key files across SIGUSR1 or --ping-restart.
30925 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30926 Don't close and reopen TUN/TAP device or run up/down scripts across
30927 SIGUSR1 or --ping-restart restarts.
30929 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30930 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30931 poll/epoll/select prior to the write operation.
30933 @item @code{verbosity} (default: @code{3}) (type: number)
30936 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-server)
30937 Add an additional layer of HMAC authentication on top of the TLS control
30938 channel to protect against DoS attacks.
30940 @item @code{port} (default: @code{1194}) (type: number)
30941 Specifies the port number on which the server listens.
30943 @item @code{server} (default: @code{"10.8.0.0 255.255.255.0"}) (type: ip-mask)
30944 An ip and mask specifying the subnet inside the virtual network.
30946 @item @code{server-ipv6} (default: @code{#f}) (type: cidr6)
30947 A CIDR notation specifying the IPv6 subnet inside the virtual network.
30949 @item @code{dh} (default: @code{"/etc/openvpn/dh2048.pem"}) (type: string)
30950 The Diffie-Hellman parameters file.
30952 @item @code{ifconfig-pool-persist} (default: @code{"/etc/openvpn/ipp.txt"}) (type: string)
30953 The file that records client IPs.
30955 @item @code{redirect-gateway?} (default: @code{#f}) (type: gateway)
30956 When true, the server will act as a gateway for its clients.
30958 @item @code{client-to-client?} (default: @code{#f}) (type: boolean)
30959 When true, clients are allowed to talk to each other inside the VPN.
30961 @item @code{keepalive} (default: @code{(10 120)}) (type: keepalive)
30962 Causes ping-like messages to be sent back and forth over the link so
30963 that each side knows when the other side has gone down. @code{keepalive}
30964 requires a pair. The first element is the period of the ping sending,
30965 and the second element is the timeout before considering the other side
30968 @item @code{max-clients} (default: @code{100}) (type: number)
30969 The maximum number of clients.
30971 @item @code{status} (default: @code{"/var/run/openvpn/status"}) (type: string)
30972 The status file. This file shows a small report on current connection.
30973 It is truncated and rewritten every minute.
30975 @item @code{client-config-dir} (default: @code{()}) (type: openvpn-ccd-list)
30976 The list of configuration for some clients.
30982 @c %end of automatic openvpn-server documentation
30984 @subheading strongSwan
30986 Currently, the strongSwan service only provides legacy-style configuration with
30987 @file{ipsec.conf} and @file{ipsec.secrets} files.
30989 @defvr {Scheme Variable} strongswan-service-type
30990 A service type for configuring strongSwan for IPsec @acronym{VPN,
30991 Virtual Private Networking}. Its value must be a
30992 @code{strongswan-configuration} record as in this example:
30995 (service strongswan-service-type
30996 (strongswan-configuration
30997 (ipsec-conf "/etc/ipsec.conf")
30998 (ipsec-secrets "/etc/ipsec.secrets")))
31003 @deftp {Data Type} strongswan-configuration
31004 Data type representing the configuration of the StrongSwan service.
31007 @item @code{strongswan}
31008 The strongSwan package to use for this service.
31010 @item @code{ipsec-conf} (default: @code{#f})
31011 The file name of your @file{ipsec.conf}. If not @code{#f}, then this and
31012 @code{ipsec-secrets} must both be strings.
31014 @item @code{ipsec-secrets} (default @code{#f})
31015 The file name of your @file{ipsec.secrets}. If not @code{#f}, then this and
31016 @code{ipsec-conf} must both be strings.
31021 @subsubheading Wireguard
31023 @defvr {Scheme Variable} wireguard-service-type
31024 A service type for a Wireguard tunnel interface. Its value must be a
31025 @code{wireguard-configuration} record as in this example:
31028 (service wireguard-service-type
31029 (wireguard-configuration
31034 (endpoint "my.wireguard.com:51820")
31035 (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
31036 (allowed-ips '("10.0.0.2/32")))))))
31041 @deftp {Data Type} wireguard-configuration
31042 Data type representing the configuration of the Wireguard service.
31045 @item @code{wireguard}
31046 The wireguard package to use for this service.
31048 @item @code{interface} (default: @code{"wg0"})
31049 The interface name for the VPN.
31051 @item @code{addresses} (default: @code{'("10.0.0.1/32")})
31052 The IP addresses to be assigned to the above interface.
31054 @item @code{port} (default: @code{51820})
31055 The port on which to listen for incoming connections.
31057 @item @code{dns} (default: @code{#f})
31058 The DNS server(s) to announce to VPN clients via DHCP.
31060 @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
31061 The private key file for the interface. It is automatically generated if
31062 the file does not exist.
31064 @item @code{peers} (default: @code{'()})
31065 The authorized peers on this interface. This is a list of
31066 @var{wireguard-peer} records.
31071 @deftp {Data Type} wireguard-peer
31072 Data type representing a Wireguard peer attached to a given interface.
31078 @item @code{endpoint} (default: @code{#f})
31079 The optional endpoint for the peer, such as
31080 @code{"demo.wireguard.com:51820"}.
31082 @item @code{public-key}
31083 The peer public-key represented as a base64 string.
31085 @item @code{allowed-ips}
31086 A list of IP addresses from which incoming traffic for this peer is
31087 allowed and to which incoming traffic for this peer is directed.
31089 @item @code{keep-alive} (default: @code{#f})
31090 An optional time interval in seconds. A packet will be sent to the
31091 server endpoint once per time interval. This helps receiving
31092 incoming connections from this peer when you are behind a NAT or
31098 @node Network File System
31099 @subsection Network File System
31102 The @code{(gnu services nfs)} module provides the following services,
31103 which are most commonly used in relation to mounting or exporting
31104 directory trees as @dfn{network file systems} (NFS).
31106 While it is possible to use the individual components that together make
31107 up a Network File System service, we recommended to configure an NFS
31108 server with the @code{nfs-service-type}.
31110 @subsubheading NFS Service
31111 @cindex NFS, server
31113 The NFS service takes care of setting up all NFS component services,
31114 kernel configuration file systems, and installs configuration files in
31115 the locations that NFS expects.
31117 @defvr {Scheme Variable} nfs-service-type
31118 A service type for a complete NFS server.
31121 @deftp {Data Type} nfs-configuration
31122 This data type represents the configuration of the NFS service and all
31125 It has the following parameters:
31127 @item @code{nfs-utils} (default: @code{nfs-utils})
31128 The nfs-utils package to use.
31130 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
31131 If a list of string values is provided, the @command{rpc.nfsd} daemon
31132 will be limited to supporting the given versions of the NFS protocol.
31134 @item @code{exports} (default: @code{'()})
31135 This is a list of directories the NFS server should export. Each entry
31136 is a list consisting of two elements: a directory name and a string
31137 containing all options. This is an example in which the directory
31138 @file{/export} is served to all NFS clients as a read-only share:
31144 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
31147 @item @code{rpcmountd-port} (default: @code{#f})
31148 The network port that the @command{rpc.mountd} daemon should use.
31150 @item @code{rpcstatd-port} (default: @code{#f})
31151 The network port that the @command{rpc.statd} daemon should use.
31153 @item @code{rpcbind} (default: @code{rpcbind})
31154 The rpcbind package to use.
31156 @item @code{idmap-domain} (default: @code{"localdomain"})
31157 The local NFSv4 domain name.
31159 @item @code{nfsd-port} (default: @code{2049})
31160 The network port that the @command{nfsd} daemon should use.
31162 @item @code{nfsd-threads} (default: @code{8})
31163 The number of threads used by the @command{nfsd} daemon.
31165 @item @code{nfsd-tcp?} (default: @code{#t})
31166 Whether the @command{nfsd} daemon should listen on a TCP socket.
31168 @item @code{nfsd-udp?} (default: @code{#f})
31169 Whether the @command{nfsd} daemon should listen on a UDP socket.
31171 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31172 The directory where the pipefs file system is mounted.
31174 @item @code{debug} (default: @code{'()"})
31175 A list of subsystems for which debugging output should be enabled. This
31176 is a list of symbols. Any of these symbols are valid: @code{nfsd},
31177 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
31181 If you don't need a complete NFS service or prefer to build it yourself
31182 you can use the individual component services that are documented below.
31184 @subsubheading RPC Bind Service
31187 The RPC Bind service provides a facility to map program numbers into
31188 universal addresses.
31189 Many NFS related services use this facility. Hence it is automatically
31190 started when a dependent service starts.
31192 @defvr {Scheme Variable} rpcbind-service-type
31193 A service type for the RPC portmapper daemon.
31197 @deftp {Data Type} rpcbind-configuration
31198 Data type representing the configuration of the RPC Bind Service.
31199 This type has the following parameters:
31201 @item @code{rpcbind} (default: @code{rpcbind})
31202 The rpcbind package to use.
31204 @item @code{warm-start?} (default: @code{#t})
31205 If this parameter is @code{#t}, then the daemon will read a
31206 state file on startup thus reloading state information saved by a previous
31212 @subsubheading Pipefs Pseudo File System
31216 The pipefs file system is used to transfer NFS related data
31217 between the kernel and user space programs.
31219 @defvr {Scheme Variable} pipefs-service-type
31220 A service type for the pipefs pseudo file system.
31223 @deftp {Data Type} pipefs-configuration
31224 Data type representing the configuration of the pipefs pseudo file system service.
31225 This type has the following parameters:
31227 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31228 The directory to which the file system is to be attached.
31233 @subsubheading GSS Daemon Service
31236 @cindex global security system
31238 The @dfn{global security system} (GSS) daemon provides strong security for RPC
31240 Before exchanging RPC requests an RPC client must establish a security
31241 context. Typically this is done using the Kerberos command @command{kinit}
31242 or automatically at login time using PAM services (@pxref{Kerberos Services}).
31244 @defvr {Scheme Variable} gss-service-type
31245 A service type for the Global Security System (GSS) daemon.
31248 @deftp {Data Type} gss-configuration
31249 Data type representing the configuration of the GSS daemon service.
31250 This type has the following parameters:
31252 @item @code{nfs-utils} (default: @code{nfs-utils})
31253 The package in which the @command{rpc.gssd} command is to be found.
31255 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31256 The directory where the pipefs file system is mounted.
31262 @subsubheading IDMAP Daemon Service
31264 @cindex name mapper
31266 The idmap daemon service provides mapping between user IDs and user names.
31267 Typically it is required in order to access file systems mounted via NFSv4.
31269 @defvr {Scheme Variable} idmap-service-type
31270 A service type for the Identity Mapper (IDMAP) daemon.
31273 @deftp {Data Type} idmap-configuration
31274 Data type representing the configuration of the IDMAP daemon service.
31275 This type has the following parameters:
31277 @item @code{nfs-utils} (default: @code{nfs-utils})
31278 The package in which the @command{rpc.idmapd} command is to be found.
31280 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31281 The directory where the pipefs file system is mounted.
31283 @item @code{domain} (default: @code{#f})
31284 The local NFSv4 domain name.
31285 This must be a string or @code{#f}.
31286 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
31288 @item @code{verbosity} (default: @code{0})
31289 The verbosity level of the daemon.
31294 @node Continuous Integration
31295 @subsection Continuous Integration
31297 @cindex continuous integration
31298 @uref{https://guix.gnu.org/cuirass/, Cuirass} is a continuous
31299 integration tool for Guix. It can be used both for development and for
31300 providing substitutes to others (@pxref{Substitutes}).
31302 The @code{(gnu services cuirass)} module provides the following service.
31304 @defvr {Scheme Procedure} cuirass-service-type
31305 The type of the Cuirass service. Its value must be a
31306 @code{cuirass-configuration} object, as described below.
31309 To add build jobs, you have to set the @code{specifications} field of
31310 the configuration. For instance, the following example will build all
31311 the packages provided by the @code{my-channel} channel.
31314 (define %cuirass-specs
31315 #~(list (specification
31316 (name "my-channel")
31317 (build '(channels my-channel))
31321 (url "https://my-channel.git"))
31322 %default-channels)))))
31324 (service cuirass-service-type
31325 (cuirass-configuration
31326 (specifications %cuirass-specs)))
31329 To build the @code{linux-libre} package defined by the default Guix
31330 channel, one can use the following configuration.
31333 (define %cuirass-specs
31334 #~(list (specification
31336 (build '(packages "linux-libre")))))
31338 (service cuirass-service-type
31339 (cuirass-configuration
31340 (specifications %cuirass-specs)))
31343 The other configuration possibilities, as well as the specification
31344 record itself are described in the Cuirass manual
31345 (@pxref{Specifications,,, cuirass, Cuirass}).
31347 While information related to build jobs is located directly in the
31348 specifications, global settings for the @command{cuirass} process are
31349 accessible in other @code{cuirass-configuration} fields.
31351 @deftp {Data Type} cuirass-configuration
31352 Data type representing the configuration of Cuirass.
31355 @item @code{cuirass} (default: @code{cuirass})
31356 The Cuirass package to use.
31358 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
31359 Location of the log file.
31361 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
31362 Location of the log file used by the web interface.
31364 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
31365 Location of the repository cache.
31367 @item @code{user} (default: @code{"cuirass"})
31368 Owner of the @code{cuirass} process.
31370 @item @code{group} (default: @code{"cuirass"})
31371 Owner's group of the @code{cuirass} process.
31373 @item @code{interval} (default: @code{60})
31374 Number of seconds between the poll of the repositories followed by the
31377 @item @code{parameters} (default: @code{#f})
31378 Read parameters from the given @var{parameters} file. The supported
31379 parameters are described here (@pxref{Parameters,,, cuirass, Cuirass}).
31381 @item @code{remote-server} (default: @code{#f})
31382 A @code{cuirass-remote-server-configuration} record to use the build
31383 remote mechanism or @code{#f} to use the default build mechanism.
31385 @item @code{database} (default: @code{"dbname=cuirass host=/var/run/postgresql"})
31386 Use @var{database} as the database containing the jobs and the past
31387 build results. Since Cuirass uses PostgreSQL as a database engine,
31388 @var{database} must be a string such as @code{"dbname=cuirass
31391 @item @code{port} (default: @code{8081})
31392 Port number used by the HTTP server.
31394 @item @code{host} (default: @code{"localhost"})
31395 Listen on the network interface for @var{host}. The default is to
31396 accept connections from localhost.
31398 @item @code{specifications} (default: @code{#~'()})
31399 A gexp (@pxref{G-Expressions}) that evaluates to a list of
31400 specifications records. The specification record is described in the
31401 Cuirass manual (@pxref{Specifications,,, cuirass, Cuirass}).
31403 @item @code{use-substitutes?} (default: @code{#f})
31404 This allows using substitutes to avoid building every dependencies of a job
31407 @item @code{one-shot?} (default: @code{#f})
31408 Only evaluate specifications and build derivations once.
31410 @item @code{fallback?} (default: @code{#f})
31411 When substituting a pre-built binary fails, fall back to building
31414 @item @code{extra-options} (default: @code{'()})
31415 Extra options to pass when running the Cuirass processes.
31420 @cindex remote build
31421 @subsubheading Cuirass remote building
31423 Cuirass supports two mechanisms to build derivations.
31426 @item Using the local Guix daemon.
31427 This is the default build mechanism. Once the build jobs are
31428 evaluated, they are sent to the local Guix daemon. Cuirass then
31429 listens to the Guix daemon output to detect the various build events.
31431 @item Using the remote build mechanism.
31432 The build jobs are not submitted to the local Guix daemon. Instead, a
31433 remote server dispatches build requests to the connect remote workers,
31434 according to the build priorities.
31438 To enable this build mode a @code{cuirass-remote-server-configuration}
31439 record must be passed as @code{remote-server} argument of the
31440 @code{cuirass-configuration} record. The
31441 @code{cuirass-remote-server-configuration} record is described below.
31443 This build mode scales way better than the default build mode. This is
31444 the build mode that is used on the GNU Guix build farm at
31445 @url{https://ci.guix.gnu.org}. It should be preferred when using
31446 Cuirass to build large amount of packages.
31448 @deftp {Data Type} cuirass-remote-server-configuration
31449 Data type representing the configuration of the Cuirass remote-server.
31452 @item @code{backend-port} (default: @code{5555})
31453 The TCP port for communicating with @code{remote-worker} processes
31454 using ZMQ. It defaults to @code{5555}.
31456 @item @code{log-port} (default: @code{5556})
31457 The TCP port of the log server. It defaults to @code{5556}.
31459 @item @code{publish-port} (default: @code{5557})
31460 The TCP port of the publish server. It defaults to @code{5557}.
31462 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-server.log"})
31463 Location of the log file.
31465 @item @code{cache} (default: @code{"/var/cache/cuirass/remote"})
31466 Use @var{cache} directory to cache build log files.
31468 @item @code{trigger-url} (default: @code{#f})
31469 Once a substitute is successfully fetched, trigger substitute baking at
31472 @item @code{publish?} (default: @code{#t})
31473 If set to false, do not start a publish server and ignore the
31474 @code{publish-port} argument. This can be useful if there is already a
31475 standalone publish server standing next to the remote server.
31477 @item @code{public-key}
31478 @item @code{private-key}
31479 Use the specific @var{file}s as the public/private key pair used to sign
31480 the store items being published.
31485 At least one remote worker must also be started on any machine of the
31486 local network to actually perform the builds and report their status.
31488 @deftp {Data Type} cuirass-remote-worker-configuration
31489 Data type representing the configuration of the Cuirass remote-worker.
31492 @item @code{cuirass} (default: @code{cuirass})
31493 The Cuirass package to use.
31495 @item @code{workers} (default: @code{1})
31496 Start @var{workers} parallel workers.
31498 @item @code{server} (default: @code{#f})
31499 Do not use Avahi discovery and connect to the given @code{server} IP
31502 @item @code{systems} (default: @code{(list (%current-system))})
31503 Only request builds for the given @var{systems}.
31505 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-worker.log"})
31506 Location of the log file.
31508 @item @code{publish-port} (default: @code{5558})
31509 The TCP port of the publish server. It defaults to @code{5558}.
31511 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
31512 The list of URLs where to look for substitutes by default.
31514 @item @code{public-key}
31515 @item @code{private-key}
31516 Use the specific @var{file}s as the public/private key pair used to sign
31517 the store items being published.
31522 @subsubheading Laminar
31524 @uref{https://laminar.ohwg.net/, Laminar} is a lightweight and modular
31525 Continuous Integration service. It doesn't have a configuration web UI
31526 instead uses version-controllable configuration files and scripts.
31528 Laminar encourages the use of existing tools such as bash and cron
31529 instead of reinventing them.
31531 @defvr {Scheme Procedure} laminar-service-type
31532 The type of the Laminar service. Its value must be a
31533 @code{laminar-configuration} object, as described below.
31535 All configuration values have defaults, a minimal configuration to get
31536 Laminar running is shown below. By default, the web interface is
31537 available on port 8080.
31540 (service laminar-service-type)
31544 @deftp {Data Type} laminar-configuration
31545 Data type representing the configuration of Laminar.
31548 @item @code{laminar} (default: @code{laminar})
31549 The Laminar package to use.
31551 @item @code{home-directory} (default: @code{"/var/lib/laminar"})
31552 The directory for job configurations and run directories.
31554 @item @code{bind-http} (default: @code{"*:8080"})
31555 The interface/port or unix socket on which laminard should listen for
31556 incoming connections to the web frontend.
31558 @item @code{bind-rpc} (default: @code{"unix-abstract:laminar"})
31559 The interface/port or unix socket on which laminard should listen for
31560 incoming commands such as build triggers.
31562 @item @code{title} (default: @code{"Laminar"})
31563 The page title to show in the web frontend.
31565 @item @code{keep-rundirs} (default: @code{0})
31566 Set to an integer defining how many rundirs to keep per job. The
31567 lowest-numbered ones will be deleted. The default is 0, meaning all run
31568 dirs will be immediately deleted.
31570 @item @code{archive-url} (default: @code{#f})
31571 The web frontend served by laminard will use this URL to form links to
31572 artefacts archived jobs.
31574 @item @code{base-url} (default: @code{#f})
31575 Base URL to use for links to laminar itself.
31580 @node Power Management Services
31581 @subsection Power Management Services
31584 @cindex power management with TLP
31585 @subsubheading TLP daemon
31587 The @code{(gnu services pm)} module provides a Guix service definition
31588 for the Linux power management tool TLP.
31590 TLP enables various powersaving modes in userspace and kernel.
31591 Contrary to @code{upower-service}, it is not a passive,
31592 monitoring tool, as it will apply custom settings each time a new power
31593 source is detected. More information can be found at
31594 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
31596 @deffn {Scheme Variable} tlp-service-type
31597 The service type for the TLP tool. The default settings are optimised
31598 for battery life on most systems, but you can tweak them to your heart's
31599 content by adding a valid @code{tlp-configuration}:
31601 (service tlp-service-type
31603 (cpu-scaling-governor-on-ac (list "performance"))
31604 (sched-powersave-on-bat? #t)))
31608 Each parameter definition is preceded by its type; for example,
31609 @samp{boolean foo} indicates that the @code{foo} parameter should be
31610 specified as a boolean. Types starting with @code{maybe-} denote
31611 parameters that won't show up in TLP config file when their value is
31612 left unset, or is explicitly set to the @code{%unset-value} value.
31614 @c The following documentation was initially generated by
31615 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
31616 @c documentation is better, so we shouldn't hesitate to edit below as
31617 @c needed. However if the change you want to make to this documentation
31618 @c can be done in an automated way, it's probably easier to change
31619 @c (generate-documentation) than to make it below and have to deal with
31620 @c the churn as TLP updates.
31622 Available @code{tlp-configuration} fields are:
31624 @deftypevr {@code{tlp-configuration} parameter} package tlp
31629 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
31630 Set to true if you wish to enable TLP.
31632 Defaults to @samp{#t}.
31636 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
31637 Default mode when no power supply can be detected. Alternatives are AC
31640 Defaults to @samp{"AC"}.
31644 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
31645 Number of seconds Linux kernel has to wait after the disk goes idle,
31646 before syncing on AC.
31648 Defaults to @samp{0}.
31652 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
31653 Same as @code{disk-idle-ac} but on BAT mode.
31655 Defaults to @samp{2}.
31659 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
31660 Dirty pages flushing periodicity, expressed in seconds.
31662 Defaults to @samp{15}.
31666 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
31667 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
31669 Defaults to @samp{60}.
31673 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
31674 CPU frequency scaling governor on AC mode. With intel_pstate driver,
31675 alternatives are powersave and performance. With acpi-cpufreq driver,
31676 alternatives are ondemand, powersave, performance and conservative.
31678 Defaults to @samp{disabled}.
31682 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
31683 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
31685 Defaults to @samp{disabled}.
31689 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
31690 Set the min available frequency for the scaling governor on AC.
31692 Defaults to @samp{disabled}.
31696 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
31697 Set the max available frequency for the scaling governor on AC.
31699 Defaults to @samp{disabled}.
31703 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
31704 Set the min available frequency for the scaling governor on BAT.
31706 Defaults to @samp{disabled}.
31710 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
31711 Set the max available frequency for the scaling governor on BAT.
31713 Defaults to @samp{disabled}.
31717 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
31718 Limit the min P-state to control the power dissipation of the CPU, in AC
31719 mode. Values are stated as a percentage of the available performance.
31721 Defaults to @samp{disabled}.
31725 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
31726 Limit the max P-state to control the power dissipation of the CPU, in AC
31727 mode. Values are stated as a percentage of the available performance.
31729 Defaults to @samp{disabled}.
31733 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
31734 Same as @code{cpu-min-perf-on-ac} on BAT mode.
31736 Defaults to @samp{disabled}.
31740 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
31741 Same as @code{cpu-max-perf-on-ac} on BAT mode.
31743 Defaults to @samp{disabled}.
31747 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
31748 Enable CPU turbo boost feature on AC mode.
31750 Defaults to @samp{disabled}.
31754 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
31755 Same as @code{cpu-boost-on-ac?} on BAT mode.
31757 Defaults to @samp{disabled}.
31761 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
31762 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
31763 used under light load conditions.
31765 Defaults to @samp{#f}.
31769 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
31770 Same as @code{sched-powersave-on-ac?} but on BAT mode.
31772 Defaults to @samp{#t}.
31776 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
31777 Enable Linux kernel NMI watchdog.
31779 Defaults to @samp{#f}.
31783 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
31784 For Linux kernels with PHC patch applied, change CPU voltages. An
31785 example value would be @samp{"F:V F:V F:V F:V"}.
31787 Defaults to @samp{disabled}.
31791 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
31792 Set CPU performance versus energy saving policy on AC@. Alternatives are
31793 performance, normal, powersave.
31795 Defaults to @samp{"performance"}.
31799 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
31800 Same as @code{energy-perf-policy-ac} but on BAT mode.
31802 Defaults to @samp{"powersave"}.
31806 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
31811 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
31812 Hard disk advanced power management level.
31816 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
31817 Same as @code{disk-apm-bat} but on BAT mode.
31821 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
31822 Hard disk spin down timeout. One value has to be specified for each
31823 declared hard disk.
31825 Defaults to @samp{disabled}.
31829 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
31830 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
31832 Defaults to @samp{disabled}.
31836 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
31837 Select IO scheduler for disk devices. One value has to be specified for
31838 each declared hard disk. Example alternatives are cfq, deadline and
31841 Defaults to @samp{disabled}.
31845 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
31846 SATA aggressive link power management (ALPM) level. Alternatives are
31847 min_power, medium_power, max_performance.
31849 Defaults to @samp{"max_performance"}.
31853 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
31854 Same as @code{sata-linkpwr-ac} but on BAT mode.
31856 Defaults to @samp{"min_power"}.
31860 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
31861 Exclude specified SATA host devices for link power management.
31863 Defaults to @samp{disabled}.
31867 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
31868 Enable Runtime Power Management for AHCI controller and disks on AC
31871 Defaults to @samp{disabled}.
31875 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
31876 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
31878 Defaults to @samp{disabled}.
31882 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
31883 Seconds of inactivity before disk is suspended.
31885 Defaults to @samp{15}.
31889 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
31890 PCI Express Active State Power Management level. Alternatives are
31891 default, performance, powersave.
31893 Defaults to @samp{"performance"}.
31897 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
31898 Same as @code{pcie-aspm-ac} but on BAT mode.
31900 Defaults to @samp{"powersave"}.
31904 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat0
31905 Percentage when battery 0 should begin charging. Only supported on some laptops.
31907 Defaults to @samp{disabled}.
31911 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat0
31912 Percentage when battery 0 should stop charging. Only supported on some laptops.
31914 Defaults to @samp{disabled}.
31918 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat1
31919 Percentage when battery 1 should begin charging. Only supported on some laptops.
31921 Defaults to @samp{disabled}.
31925 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat1
31926 Percentage when battery 1 should stop charging. Only supported on some laptops.
31928 Defaults to @samp{disabled}.
31932 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
31933 Radeon graphics clock speed level. Alternatives are low, mid, high,
31936 Defaults to @samp{"high"}.
31940 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
31941 Same as @code{radeon-power-ac} but on BAT mode.
31943 Defaults to @samp{"low"}.
31947 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
31948 Radeon dynamic power management method (DPM). Alternatives are battery,
31951 Defaults to @samp{"performance"}.
31955 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
31956 Same as @code{radeon-dpm-state-ac} but on BAT mode.
31958 Defaults to @samp{"battery"}.
31962 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
31963 Radeon DPM performance level. Alternatives are auto, low, high.
31965 Defaults to @samp{"auto"}.
31969 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
31970 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
31972 Defaults to @samp{"auto"}.
31976 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
31977 Wifi power saving mode.
31979 Defaults to @samp{#f}.
31983 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
31984 Same as @code{wifi-power-ac?} but on BAT mode.
31986 Defaults to @samp{#t}.
31990 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
31991 Disable wake on LAN.
31993 Defaults to @samp{#t}.
31997 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
31998 Timeout duration in seconds before activating audio power saving on
31999 Intel HDA and AC97 devices. A value of 0 disables power saving.
32001 Defaults to @samp{0}.
32005 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
32006 Same as @code{sound-powersave-ac} but on BAT mode.
32008 Defaults to @samp{1}.
32012 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
32013 Disable controller in powersaving mode on Intel HDA devices.
32015 Defaults to @samp{#t}.
32019 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
32020 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
32021 powered on again by releasing (and reinserting) the eject lever or by
32022 pressing the disc eject button on newer models.
32024 Defaults to @samp{#f}.
32028 @deftypevr {@code{tlp-configuration} parameter} string bay-device
32029 Name of the optical drive device to power off.
32031 Defaults to @samp{"sr0"}.
32035 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
32036 Runtime Power Management for PCI(e) bus devices. Alternatives are on
32039 Defaults to @samp{"on"}.
32043 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
32044 Same as @code{runtime-pm-ac} but on BAT mode.
32046 Defaults to @samp{"auto"}.
32050 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
32051 Runtime Power Management for all PCI(e) bus devices, except blacklisted
32054 Defaults to @samp{#t}.
32058 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
32059 Exclude specified PCI(e) device addresses from Runtime Power Management.
32061 Defaults to @samp{disabled}.
32065 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
32066 Exclude PCI(e) devices assigned to the specified drivers from Runtime
32071 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
32072 Enable USB autosuspend feature.
32074 Defaults to @samp{#t}.
32078 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
32079 Exclude specified devices from USB autosuspend.
32081 Defaults to @samp{disabled}.
32085 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
32086 Exclude WWAN devices from USB autosuspend.
32088 Defaults to @samp{#t}.
32092 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
32093 Include specified devices into USB autosuspend, even if they are already
32094 excluded by the driver or via @code{usb-blacklist-wwan?}.
32096 Defaults to @samp{disabled}.
32100 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
32101 Enable USB autosuspend before shutdown.
32103 Defaults to @samp{disabled}.
32107 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
32108 Restore radio device state (bluetooth, wifi, wwan) from previous
32109 shutdown on system startup.
32111 Defaults to @samp{#f}.
32116 @cindex CPU frequency scaling with thermald
32117 @subsubheading Thermald daemon
32119 The @code{(gnu services pm)} module provides an interface to
32120 thermald, a CPU frequency scaling service which helps prevent overheating.
32122 @defvr {Scheme Variable} thermald-service-type
32123 This is the service type for
32124 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
32125 Thermal Daemon, which is responsible for controlling the thermal state
32126 of processors and preventing overheating.
32129 @deftp {Data Type} thermald-configuration
32130 Data type representing the configuration of @code{thermald-service-type}.
32133 @item @code{adaptive?} (default: @code{#f})
32134 Use @acronym{DPTF, Dynamic Power and Thermal Framework} adaptive tables
32137 @item @code{ignore-cpuid-check?} (default: @code{#f})
32138 Ignore cpuid check for supported CPU models.
32140 @item @code{thermald} (default: @var{thermald})
32141 Package object of thermald.
32146 @node Audio Services
32147 @subsection Audio Services
32149 The @code{(gnu services audio)} module provides a service to start MPD
32150 (the Music Player Daemon).
32153 @subsubheading Music Player Daemon
32155 The Music Player Daemon (MPD) is a service that can play music while
32156 being controlled from the local machine or over the network by a variety
32159 The following example shows how one might run @code{mpd} as user
32160 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
32163 (service mpd-service-type
32169 @defvr {Scheme Variable} mpd-service-type
32170 The service type for @command{mpd}
32173 @deftp {Data Type} mpd-configuration
32174 Data type representing the configuration of @command{mpd}.
32177 @item @code{user} (default: @code{"mpd"})
32178 The user to run mpd as.
32180 @item @code{music-dir} (default: @code{"~/Music"})
32181 The directory to scan for music files.
32183 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
32184 The directory to store playlists.
32186 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
32187 The location of the music database.
32189 @item @code{state-file} (default: @code{"~/.mpd/state"})
32190 The location of the file that stores current MPD's state.
32192 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
32193 The location of the sticker database.
32195 @item @code{port} (default: @code{"6600"})
32196 The port to run mpd on.
32198 @item @code{address} (default: @code{"any"})
32199 The address that mpd will bind to. To use a Unix domain socket,
32200 an absolute path can be specified here.
32202 @item @code{outputs} (default: @code{"(list (mpd-output))"})
32203 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
32208 @deftp {Data Type} mpd-output
32209 Data type representing an @command{mpd} audio output.
32212 @item @code{name} (default: @code{"MPD"})
32213 The name of the audio output.
32215 @item @code{type} (default: @code{"pulse"})
32216 The type of audio output.
32218 @item @code{enabled?} (default: @code{#t})
32219 Specifies whether this audio output is enabled when MPD is started. By
32220 default, all audio outputs are enabled. This is just the default
32221 setting when there is no state file; with a state file, the previous
32224 @item @code{tags?} (default: @code{#t})
32225 If set to @code{#f}, then MPD will not send tags to this output. This
32226 is only useful for output plugins that can receive tags, for example the
32227 @code{httpd} output plugin.
32229 @item @code{always-on?} (default: @code{#f})
32230 If set to @code{#t}, then MPD attempts to keep this audio output always
32231 open. This may be useful for streaming servers, when you don’t want to
32232 disconnect all listeners even when playback is accidentally stopped.
32234 @item @code{mixer-type}
32235 This field accepts a symbol that specifies which mixer should be used
32236 for this audio output: the @code{hardware} mixer, the @code{software}
32237 mixer, the @code{null} mixer (allows setting the volume, but with no
32238 effect; this can be used as a trick to implement an external mixer
32239 External Mixer) or no mixer (@code{none}).
32241 @item @code{extra-options} (default: @code{'()})
32242 An association list of option symbols to string values to be appended to
32243 the audio output configuration.
32248 The following example shows a configuration of @code{mpd} that provides
32249 an HTTP audio streaming output.
32252 (service mpd-service-type
32260 `((encoder . "vorbis")
32261 (port . "8080"))))))))
32265 @node Virtualization Services
32266 @subsection Virtualization Services
32268 The @code{(gnu services virtualization)} module provides services for
32269 the libvirt and virtlog daemons, as well as other virtualization-related
32272 @subsubheading Libvirt daemon
32274 @code{libvirtd} is the server side daemon component of the libvirt
32275 virtualization management system. This daemon runs on host servers
32276 and performs required management tasks for virtualized guests.
32278 @deffn {Scheme Variable} libvirt-service-type
32279 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
32280 Its value must be a @code{libvirt-configuration}.
32283 (service libvirt-service-type
32284 (libvirt-configuration
32285 (unix-sock-group "libvirt")
32286 (tls-port "16555")))
32290 @c Auto-generated with (generate-libvirt-documentation)
32291 Available @code{libvirt-configuration} fields are:
32293 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
32298 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
32299 Flag listening for secure TLS connections on the public TCP/IP port.
32300 You must set @code{listen} for this to have any effect.
32302 It is necessary to setup a CA and issue server certificates before using
32305 Defaults to @samp{#t}.
32309 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
32310 Listen for unencrypted TCP connections on the public TCP/IP port. You must
32311 set @code{listen} for this to have any effect.
32313 Using the TCP socket requires SASL authentication by default. Only SASL
32314 mechanisms which support data encryption are allowed. This is
32315 DIGEST_MD5 and GSSAPI (Kerberos5).
32317 Defaults to @samp{#f}.
32321 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
32322 Port for accepting secure TLS connections. This can be a port number,
32325 Defaults to @samp{"16514"}.
32329 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
32330 Port for accepting insecure TCP connections. This can be a port number,
32333 Defaults to @samp{"16509"}.
32337 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
32338 IP address or hostname used for client connections.
32340 Defaults to @samp{"0.0.0.0"}.
32344 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
32345 Flag toggling mDNS advertisement of the libvirt service.
32347 Alternatively can disable for all services on a host by stopping the
32350 Defaults to @samp{#f}.
32354 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
32355 Default mDNS advertisement name. This must be unique on the immediate
32358 Defaults to @samp{"Virtualization Host <hostname>"}.
32362 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
32363 UNIX domain socket group ownership. This can be used to allow a
32364 'trusted' set of users access to management capabilities without
32367 Defaults to @samp{"root"}.
32371 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
32372 UNIX socket permissions for the R/O socket. This is used for monitoring
32375 Defaults to @samp{"0777"}.
32379 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
32380 UNIX socket permissions for the R/W socket. Default allows only root.
32381 If PolicyKit is enabled on the socket, the default will change to allow
32382 everyone (eg, 0777)
32384 Defaults to @samp{"0770"}.
32388 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
32389 UNIX socket permissions for the admin socket. Default allows only owner
32390 (root), do not change it unless you are sure to whom you are exposing
32393 Defaults to @samp{"0777"}.
32397 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
32398 The directory in which sockets will be found/created.
32400 Defaults to @samp{"/var/run/libvirt"}.
32404 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
32405 Authentication scheme for UNIX read-only sockets. By default socket
32406 permissions allow anyone to connect
32408 Defaults to @samp{"polkit"}.
32412 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
32413 Authentication scheme for UNIX read-write sockets. By default socket
32414 permissions only allow root. If PolicyKit support was compiled into
32415 libvirt, the default will be to use 'polkit' auth.
32417 Defaults to @samp{"polkit"}.
32421 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
32422 Authentication scheme for TCP sockets. If you don't enable SASL, then
32423 all TCP traffic is cleartext. Don't do this outside of a dev/test
32426 Defaults to @samp{"sasl"}.
32430 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
32431 Authentication scheme for TLS sockets. TLS sockets already have
32432 encryption provided by the TLS layer, and limited authentication is done
32435 It is possible to make use of any SASL authentication mechanism as well,
32436 by using 'sasl' for this option
32438 Defaults to @samp{"none"}.
32442 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
32443 API access control scheme.
32445 By default an authenticated user is allowed access to all APIs. Access
32446 drivers can place restrictions on this.
32448 Defaults to @samp{()}.
32452 @deftypevr {@code{libvirt-configuration} parameter} string key-file
32453 Server key file path. If set to an empty string, then no private key is
32456 Defaults to @samp{""}.
32460 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
32461 Server key file path. If set to an empty string, then no certificate is
32464 Defaults to @samp{""}.
32468 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
32469 Server key file path. If set to an empty string, then no CA certificate
32472 Defaults to @samp{""}.
32476 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
32477 Certificate revocation list path. If set to an empty string, then no
32480 Defaults to @samp{""}.
32484 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
32485 Disable verification of our own server certificates.
32487 When libvirtd starts it performs some sanity checks against its own
32490 Defaults to @samp{#f}.
32494 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
32495 Disable verification of client certificates.
32497 Client certificate verification is the primary authentication mechanism.
32498 Any client which does not present a certificate signed by the CA will be
32501 Defaults to @samp{#f}.
32505 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
32506 Whitelist of allowed x509 Distinguished Name.
32508 Defaults to @samp{()}.
32512 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
32513 Whitelist of allowed SASL usernames. The format for username depends on
32514 the SASL authentication mechanism.
32516 Defaults to @samp{()}.
32520 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
32521 Override the compile time default TLS priority string. The default is
32522 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
32523 is desired for libvirt to deviate from the global default settings.
32525 Defaults to @samp{"NORMAL"}.
32529 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
32530 Maximum number of concurrent client connections to allow over all
32533 Defaults to @samp{5000}.
32537 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
32538 Maximum length of queue of connections waiting to be accepted by the
32539 daemon. Note, that some protocols supporting retransmission may obey
32540 this so that a later reattempt at connection succeeds.
32542 Defaults to @samp{1000}.
32546 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
32547 Maximum length of queue of accepted but not yet authenticated clients.
32548 Set this to zero to turn this feature off
32550 Defaults to @samp{20}.
32554 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
32555 Number of workers to start up initially.
32557 Defaults to @samp{5}.
32561 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
32562 Maximum number of worker threads.
32564 If the number of active clients exceeds @code{min-workers}, then more
32565 threads are spawned, up to max_workers limit. Typically you'd want
32566 max_workers to equal maximum number of clients allowed.
32568 Defaults to @samp{20}.
32572 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
32573 Number of priority workers. If all workers from above pool are stuck,
32574 some calls marked as high priority (notably domainDestroy) can be
32575 executed in this pool.
32577 Defaults to @samp{5}.
32581 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
32582 Total global limit on concurrent RPC calls.
32584 Defaults to @samp{20}.
32588 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
32589 Limit on concurrent requests from a single client connection. To avoid
32590 one client monopolizing the server this should be a small fraction of
32591 the global max_requests and max_workers parameter.
32593 Defaults to @samp{5}.
32597 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
32598 Same as @code{min-workers} but for the admin interface.
32600 Defaults to @samp{1}.
32604 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
32605 Same as @code{max-workers} but for the admin interface.
32607 Defaults to @samp{5}.
32611 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
32612 Same as @code{max-clients} but for the admin interface.
32614 Defaults to @samp{5}.
32618 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
32619 Same as @code{max-queued-clients} but for the admin interface.
32621 Defaults to @samp{5}.
32625 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
32626 Same as @code{max-client-requests} but for the admin interface.
32628 Defaults to @samp{5}.
32632 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
32633 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32635 Defaults to @samp{3}.
32639 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
32642 A filter allows to select a different logging level for a given category
32643 of logs. The format for a filter is one of:
32654 where @code{name} is a string which is matched against the category
32655 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32656 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
32657 name in the filter can be a substring of the full category name, in
32658 order to match multiple similar categories), the optional @samp{"+"}
32659 prefix tells libvirt to log stack trace for each message matching name,
32660 and @code{x} is the minimal level where matching messages should be
32678 Multiple filters can be defined in a single filters statement, they just
32679 need to be separated by spaces.
32681 Defaults to @samp{"3:remote 4:event"}.
32685 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
32688 An output is one of the places to save logging information. The format
32689 for an output can be:
32693 output goes to stderr
32695 @item x:syslog:name
32696 use syslog for the output and use the given name as the ident
32698 @item x:file:file_path
32699 output to a file, with the given filepath
32702 output to journald logging system
32706 In all case the x prefix is the minimal level, acting as a filter
32723 Multiple outputs can be defined, they just need to be separated by
32726 Defaults to @samp{"3:stderr"}.
32730 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
32731 Allows usage of the auditing subsystem to be altered
32735 0: disable all auditing
32738 1: enable auditing, only if enabled on host
32741 2: enable auditing, and exit if disabled on host.
32745 Defaults to @samp{1}.
32749 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
32750 Send audit messages via libvirt logging infrastructure.
32752 Defaults to @samp{#f}.
32756 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
32757 Host UUID@. UUID must not have all digits be the same.
32759 Defaults to @samp{""}.
32763 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
32764 Source to read host UUID.
32768 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
32771 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
32775 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
32778 Defaults to @samp{"smbios"}.
32782 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
32783 A keepalive message is sent to a client after @code{keepalive_interval}
32784 seconds of inactivity to check if the client is still responding. If
32785 set to -1, libvirtd will never send keepalive requests; however clients
32786 can still send them and the daemon will send responses.
32788 Defaults to @samp{5}.
32792 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
32793 Maximum number of keepalive messages that are allowed to be sent to the
32794 client without getting any response before the connection is considered
32797 In other words, the connection is automatically closed approximately
32798 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
32799 the last message received from the client. When @code{keepalive-count}
32800 is set to 0, connections will be automatically closed after
32801 @code{keepalive-interval} seconds of inactivity without sending any
32802 keepalive messages.
32804 Defaults to @samp{5}.
32808 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
32809 Same as above but for admin interface.
32811 Defaults to @samp{5}.
32815 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
32816 Same as above but for admin interface.
32818 Defaults to @samp{5}.
32822 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
32823 Timeout for Open vSwitch calls.
32825 The @code{ovs-vsctl} utility is used for the configuration and its
32826 timeout option is set by default to 5 seconds to avoid potential
32827 infinite waits blocking libvirt.
32829 Defaults to @samp{5}.
32833 @c %end of autogenerated docs
32835 @subsubheading Virtlog daemon
32836 The virtlogd service is a server side daemon component of libvirt that is
32837 used to manage logs from virtual machine consoles.
32839 This daemon is not used directly by libvirt client applications, rather it
32840 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
32841 standalone daemon, the main @code{libvirtd} daemon can be restarted without
32842 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
32843 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
32845 @deffn {Scheme Variable} virtlog-service-type
32846 This is the type of the virtlog daemon.
32847 Its value must be a @code{virtlog-configuration}.
32850 (service virtlog-service-type
32851 (virtlog-configuration
32852 (max-clients 1000)))
32856 @deftypevar {@code{libvirt} parameter} package libvirt
32860 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
32861 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32863 Defaults to @samp{3}.
32867 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
32870 A filter allows to select a different logging level for a given category
32871 of logs The format for a filter is one of:
32882 where @code{name} is a string which is matched against the category
32883 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32884 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
32885 be a substring of the full category name, in order to match multiple
32886 similar categories), the optional "+" prefix tells libvirt to log stack
32887 trace for each message matching name, and @code{x} is the minimal level
32888 where matching messages should be logged:
32905 Multiple filters can be defined in a single filters statement, they just
32906 need to be separated by spaces.
32908 Defaults to @samp{"3:remote 4:event"}.
32912 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
32915 An output is one of the places to save logging information The format
32916 for an output can be:
32920 output goes to stderr
32922 @item x:syslog:name
32923 use syslog for the output and use the given name as the ident
32925 @item x:file:file_path
32926 output to a file, with the given filepath
32929 output to journald logging system
32933 In all case the x prefix is the minimal level, acting as a filter
32950 Multiple outputs can be defined, they just need to be separated by
32953 Defaults to @samp{"3:stderr"}.
32957 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
32958 Maximum number of concurrent client connections to allow over all
32961 Defaults to @samp{1024}.
32965 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
32966 Maximum file size before rolling over.
32968 Defaults to @samp{2MB}
32972 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
32973 Maximum number of backup files to keep.
32975 Defaults to @samp{3}
32979 @anchor{transparent-emulation-qemu}
32980 @subsubheading Transparent Emulation with QEMU
32983 @cindex @code{binfmt_misc}
32984 @code{qemu-binfmt-service-type} provides support for transparent
32985 emulation of program binaries built for different architectures---e.g.,
32986 it allows you to transparently execute an ARMv7 program on an x86_64
32987 machine. It achieves this by combining the @uref{https://www.qemu.org,
32988 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
32989 This feature only allows you to emulate GNU/Linux on a different
32990 architecture, but see below for GNU/Hurd support.
32992 @defvr {Scheme Variable} qemu-binfmt-service-type
32993 This is the type of the QEMU/binfmt service for transparent emulation.
32994 Its value must be a @code{qemu-binfmt-configuration} object, which
32995 specifies the QEMU package to use as well as the architecture we want to
32999 (service qemu-binfmt-service-type
33000 (qemu-binfmt-configuration
33001 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
33004 In this example, we enable transparent emulation for the ARM and aarch64
33005 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
33006 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
33007 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
33010 @deftp {Data Type} qemu-binfmt-configuration
33011 This is the configuration for the @code{qemu-binfmt} service.
33014 @item @code{platforms} (default: @code{'()})
33015 The list of emulated QEMU platforms. Each item must be a @dfn{platform
33016 object} as returned by @code{lookup-qemu-platforms} (see below).
33018 For example, let's suppose you're on an x86_64 machine and you have this
33022 (service qemu-binfmt-service-type
33023 (qemu-binfmt-configuration
33024 (platforms (lookup-qemu-platforms "arm"))))
33030 guix build -s armhf-linux inkscape
33034 and it will build Inkscape for ARMv7 @emph{as if it were a native
33035 build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
33036 if you'd like to test a package build for an architecture you don't have
33039 @item @code{qemu} (default: @code{qemu})
33040 The QEMU package to use.
33044 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
33045 Return the list of QEMU platform objects corresponding to
33046 @var{platforms}@dots{}. @var{platforms} must be a list of strings
33047 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
33048 @code{"mips64el"}, and so on.
33051 @deffn {Scheme Procedure} qemu-platform? @var{obj}
33052 Return true if @var{obj} is a platform object.
33055 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
33056 Return the name of @var{platform}---a string such as @code{"arm"}.
33060 @subsubheading QEMU Guest Agent
33064 The QEMU guest agent provides control over the emulated system to the
33065 host. The @code{qemu-guest-agent} service runs the agent on Guix
33066 guests. To control the agent from the host, open a socket by invoking
33067 QEMU with the following arguments:
33070 qemu-system-x86_64 \
33071 -chardev socket,path=/tmp/qga.sock,server=on,wait=off,id=qga0 \
33072 -device virtio-serial \
33073 -device virtserialport,chardev=qga0,name=org.qemu.guest_agent.0 \
33077 This creates a socket at @file{/tmp/qga.sock} on the host. Once the
33078 guest agent is running, you can issue commands with @code{socat}:
33081 $ guix shell socat -- socat unix-connect:/tmp/qga.sock stdio
33082 @{"execute": "guest-get-host-name"@}
33083 @{"return": @{"host-name": "guix"@}@}
33086 See @url{https://wiki.qemu.org/Features/GuestAgent,QEMU guest agent
33087 documentation} for more options and commands.
33089 @defvr {Scheme Variable} qemu-guest-agent-service-type
33090 Service type for the QEMU guest agent service.
33093 @deftp {Data Type} qemu-guest-agent-configuration
33094 Configuration for the @code{qemu-guest-agent} service.
33097 @item @code{qemu} (default: @code{qemu-minimal})
33098 The QEMU package to use.
33100 @item @code{device} (default: @code{""})
33101 File name of the device or socket the agent uses to communicate with the
33102 host. If empty, QEMU uses a default file name.
33107 @subsubheading The Hurd in a Virtual Machine
33109 @cindex @code{hurd}
33113 Service @code{hurd-vm} provides support for running GNU/Hurd in a
33114 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
33115 to be used on GNU/Linux and the given GNU/Hurd operating system
33116 configuration is cross-compiled. The virtual machine is a Shepherd
33117 service that can be referred to by the names @code{hurd-vm} and
33118 @code{childhurd} and be controlled with commands such as:
33122 herd stop childhurd
33125 When the service is running, you can view its console by connecting to
33126 it with a VNC client, for example with:
33129 guix shell tigervnc-client -- vncviewer localhost:5900
33132 The default configuration (see @code{hurd-vm-configuration} below)
33133 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
33134 (the virtual machine emulator) redirects to port 10222 on the host.
33135 Thus, you can connect over SSH to the childhurd with:
33138 ssh root@@localhost -p 10022
33141 The childhurd is volatile and stateless: it starts with a fresh root
33142 file system every time you restart it. By default though, all the files
33143 under @file{/etc/childhurd} on the host are copied as is to the root
33144 file system of the childhurd when it boots. This allows you to
33145 initialize ``secrets'' inside the VM: SSH host keys, authorized
33146 substitute keys, and so on---see the explanation of @code{secret-root}
33149 @defvr {Scheme Variable} hurd-vm-service-type
33150 This is the type of the Hurd in a Virtual Machine service. Its value
33151 must be a @code{hurd-vm-configuration} object, which specifies the
33152 operating system (@pxref{operating-system Reference}) and the disk size
33153 for the Hurd Virtual Machine, the QEMU package to use as well as the
33154 options for running it.
33159 (service hurd-vm-service-type
33160 (hurd-vm-configuration
33161 (disk-size (* 5000 (expt 2 20))) ;5G
33162 (memory-size 1024))) ;1024MiB
33165 would create a disk image big enough to build GNU@tie{}Hello, with some
33169 @deftp {Data Type} hurd-vm-configuration
33170 The data type representing the configuration for
33171 @code{hurd-vm-service-type}.
33174 @item @code{os} (default: @var{%hurd-vm-operating-system})
33175 The operating system to instantiate. This default is bare-bones with a
33176 permissive OpenSSH secure shell daemon listening on port 2222
33177 (@pxref{Networking Services, @code{openssh-service-type}}).
33179 @item @code{qemu} (default: @code{qemu-minimal})
33180 The QEMU package to use.
33182 @item @code{image} (default: @var{hurd-vm-disk-image})
33183 The procedure used to build the disk-image built from this
33186 @item @code{disk-size} (default: @code{'guess})
33187 The size of the disk image.
33189 @item @code{memory-size} (default: @code{512})
33190 The memory size of the Virtual Machine in mebibytes.
33192 @item @code{options} (default: @code{'("--snapshot")})
33193 The extra options for running QEMU.
33195 @item @code{id} (default: @code{#f})
33196 If set, a non-zero positive integer used to parameterize Childhurd
33197 instances. It is appended to the service's name,
33198 e.g. @code{childhurd1}.
33200 @item @code{net-options} (default: @var{hurd-vm-net-options})
33201 The procedure used to produce the list of QEMU networking options.
33203 By default, it produces
33206 '("--device" "rtl8139,netdev=net0"
33207 "--netdev" (string-append
33209 "hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004,"
33210 "hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222,"
33211 "hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900"))
33214 with forwarded ports:
33217 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
33218 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
33219 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
33222 @item @code{secret-root} (default: @file{/etc/childhurd})
33223 The root directory with out-of-band secrets to be installed into the
33224 childhurd once it runs. Childhurds are volatile which means that on
33225 every startup, secrets such as the SSH host keys and Guix signing key
33228 If the @file{/etc/childhurd} directory does not exist, the
33229 @code{secret-service} running in the Childhurd will be sent an empty
33232 By default, the service automatically populates @file{/etc/childhurd}
33233 with the following non-volatile secrets, unless they already exist:
33236 /etc/childhurd/etc/guix/acl
33237 /etc/childhurd/etc/guix/signing-key.pub
33238 /etc/childhurd/etc/guix/signing-key.sec
33239 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
33240 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
33241 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
33242 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
33245 These files are automatically sent to the guest Hurd VM when it boots,
33246 including permissions.
33248 @cindex childhurd, offloading
33249 @cindex Hurd, offloading
33250 Having these files in place means that only a couple of things are
33251 missing to allow the host to offload @code{i586-gnu} builds to the
33256 Authorizing the childhurd's key on the host so that the host accepts
33257 build results coming from the childhurd, which can be done like so:
33260 guix archive --authorize < \
33261 /etc/childhurd/etc/guix/signing-key.pub
33265 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
33269 We're working towards making that happen automatically---get in touch
33270 with us at @email{guix-devel@@gnu.org} to discuss it!
33274 Note that by default the VM image is volatile, i.e., once stopped the
33275 contents are lost. If you want a stateful image instead, override the
33276 configuration's @code{image} and @code{options} without
33277 the @code{--snapshot} flag using something along these lines:
33280 (service hurd-vm-service-type
33281 (hurd-vm-configuration
33282 (image (const "/out/of/store/writable/hurd.img"))
33286 @subsubheading Ganeti
33291 This service is considered experimental. Configuration options may be changed
33292 in a backwards-incompatible manner, and not all features have been thorougly
33293 tested. Users of this service are encouraged to share their experience at
33294 @email{guix-devel@@gnu.org}.
33297 Ganeti is a virtual machine management system. It is designed to keep virtual
33298 machines running on a cluster of servers even in the event of hardware failures,
33299 and to make maintenance and recovery tasks easy. It consists of multiple
33300 services which are described later in this section. In addition to the Ganeti
33301 service, you will need the OpenSSH service (@pxref{Networking Services,
33302 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
33303 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
33304 and address (or use a DNS server).
33306 All nodes participating in a Ganeti cluster should have the same Ganeti and
33307 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
33308 cluster node that supports multiple storage backends, and installs the
33309 @code{debootstrap} and @code{guix} @dfn{OS providers}:
33312 (use-package-modules virtualization)
33313 (use-service-modules base ganeti networking ssh)
33316 (host-name "node1")
33317 (hosts-file (plain-file "hosts" (format #f "
33318 127.0.0.1 localhost
33321 192.168.1.200 ganeti.example.com
33322 192.168.1.201 node1.example.com node1
33323 192.168.1.202 node2.example.com node2
33326 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
33327 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
33328 (packages (append (map specification->package
33329 '("qemu" "lvm2" "drbd-utils" "ceph"
33330 ;; Add the debootstrap and guix OS providers.
33331 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
33334 (append (list (service static-networking-service-type
33335 (list (static-networking
33337 (list (network-address
33339 (value "192.168.1.201/24"))))
33341 (list (network-route
33342 (destination "default")
33343 (gateway "192.168.1.254"))))
33344 (name-servers '("192.168.1.252"
33345 "192.168.1.253")))))
33347 ;; Ganeti uses SSH to communicate between nodes.
33348 (service openssh-service-type
33349 (openssh-configuration
33350 (permit-root-login 'prohibit-password)))
33352 (service ganeti-service-type
33353 (ganeti-configuration
33354 ;; This list specifies allowed file system paths
33355 ;; for storing virtual machine images.
33356 (file-storage-paths '("/srv/ganeti/file-storage"))
33357 ;; This variable configures a single "variant" for
33358 ;; both Debootstrap and Guix that works with KVM.
33359 (os %default-ganeti-os))))
33363 Users are advised to read the
33364 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
33365 administrators guide} to learn about the various cluster options and
33366 day-to-day operations. There is also a
33367 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
33368 describing how to configure and initialize a small cluster.
33370 @defvr {Scheme Variable} ganeti-service-type
33371 This is a service type that includes all the various services that Ganeti
33374 Its value is a @code{ganeti-configuration} object that defines the package
33375 to use for CLI operations, as well as configuration for the various daemons.
33376 Allowed file storage paths and available guest operating systems are also
33377 configured through this data type.
33380 @deftp {Data Type} ganeti-configuration
33381 The @code{ganeti} service takes the following configuration options:
33384 @item @code{ganeti} (default: @code{ganeti})
33385 The @code{ganeti} package to use. It will be installed to the system profile
33386 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
33387 that the value specified here does not affect the other services as each refer
33388 to a specific @code{ganeti} package (see below).
33390 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
33391 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
33392 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
33393 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
33394 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
33395 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
33396 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
33397 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
33398 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
33399 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
33401 These options control the various daemons and cron jobs that are distributed
33402 with Ganeti. The possible values for these are described in detail below.
33403 To override a setting, you must use the configuration type for that service:
33406 (service ganeti-service-type
33407 (ganeti-configuration
33408 (rapi-configuration
33409 (ganeti-rapi-configuration
33410 (interface "eth1"))))
33411 (watcher-configuration
33412 (ganeti-watcher-configuration
33413 (rapi-ip "10.0.0.1"))))
33416 @item @code{file-storage-paths} (default: @code{'()})
33417 List of allowed directories for file storage backend.
33419 @item @code{os} (default: @code{%default-ganeti-os})
33420 List of @code{<ganeti-os>} records.
33423 In essence @code{ganeti-service-type} is shorthand for declaring each service
33427 (service ganeti-noded-service-type)
33428 (service ganeti-confd-service-type)
33429 (service ganeti-wconfd-service-type)
33430 (service ganeti-luxid-service-type)
33431 (service ganeti-kvmd-service-type)
33432 (service ganeti-mond-service-type)
33433 (service ganeti-metad-service-type)
33434 (service ganeti-watcher-service-type)
33435 (service ganeti-cleaner-service-type)
33438 Plus a service extension for @code{etc-service-type} that configures the file
33439 storage backend and OS variants.
33443 @deftp {Data Type} ganeti-os
33444 This data type is suitable for passing to the @code{os} parameter of
33445 @code{ganeti-configuration}. It takes the following parameters:
33449 The name for this OS provider. It is only used to specify where the
33450 configuration ends up. Setting it to ``debootstrap'' will create
33451 @file{/etc/ganeti/instance-debootstrap}.
33453 @item @code{extension}
33454 The file extension for variants of this OS type. For example
33455 @file{.conf} or @file{.scm}.
33457 @item @code{variants} (default: @code{'()})
33458 List of @code{ganeti-os-variant} objects for this OS.
33463 @deftp {Data Type} ganeti-os-variant
33464 This is the data type for a Ganeti OS variant. It takes the following
33469 The name of this variant.
33471 @item @code{configuration}
33472 A configuration file for this variant.
33476 @defvr {Scheme Variable} %default-debootstrap-hooks
33477 This variable contains hooks to configure networking and the GRUB bootloader.
33480 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
33481 This variable contains a list of packages suitable for a fully-virtualized guest.
33484 @deftp {Data Type} debootstrap-configuration
33486 This data type creates configuration files suitable for the debootstrap OS provider.
33489 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
33490 When not @code{#f}, this must be a G-expression that specifies a directory with
33491 scripts that will run when the OS is installed. It can also be a list of
33492 @code{(name . file-like)} pairs. For example:
33495 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
33498 That will create a directory with one executable named @code{99-hello-world}
33499 and run it every time this variant is installed. If set to @code{#f}, hooks
33500 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
33501 @item @code{proxy} (default: @code{#f})
33502 Optional HTTP proxy to use.
33503 @item @code{mirror} (default: @code{#f})
33504 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
33505 The default varies depending on the distribution.
33506 @item @code{arch} (default: @code{#f})
33507 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
33508 on an AArch64 host. Default is to use the current system architecture.
33509 @item @code{suite} (default: @code{"stable"})
33510 When set, this must be a Debian distribution ``suite'' such as @code{buster}
33511 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
33512 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
33513 List of extra packages that will get installed by dpkg in addition
33514 to the minimal system.
33515 @item @code{components} (default: @code{#f})
33516 When set, must be a list of Debian repository ``components''. For example
33517 @code{'("main" "contrib")}.
33518 @item @code{generate-cache?} (default: @code{#t})
33519 Whether to automatically cache the generated debootstrap archive.
33520 @item @code{clean-cache} (default: @code{14})
33521 Discard the cache after this amount of days. Use @code{#f} to never
33523 @item @code{partition-style} (default: @code{'msdos})
33524 The type of partition to create. When set, it must be one of
33525 @code{'msdos}, @code{'none} or a string.
33526 @item @code{partition-alignment} (default: @code{2048})
33527 Alignment of the partition in sectors.
33531 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
33532 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
33533 takes two parameters: a name and a @code{debootstrap-configuration} object.
33536 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
33537 This is a helper procedure that creates a @code{ganeti-os} record. It takes
33538 a list of variants created with @code{debootstrap-variant}.
33541 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
33542 This is a helper procedure that creates a @code{ganeti-os-variant} record for
33543 use with the Guix OS provider. It takes a name and a G-expression that returns
33544 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
33545 Guix System configuration.
33548 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
33549 This is a helper procedure that creates a @code{ganeti-os} record. It
33550 takes a list of variants produced by @code{guix-variant}.
33553 @defvr {Scheme Variable} %default-debootstrap-variants
33554 This is a convenience variable to make the debootstrap provider work
33555 ``out of the box'' without users having to declare variants manually. It
33556 contains a single debootstrap variant with the default configuration:
33559 (list (debootstrap-variant
33561 (debootstrap-configuration)))
33565 @defvr {Scheme Variable} %default-guix-variants
33566 This is a convenience variable to make the Guix OS provider work without
33567 additional configuration. It creates a virtual machine that has an SSH
33568 server, a serial console, and authorizes the Ganeti hosts SSH keys.
33571 (list (guix-variant
33573 (file-append ganeti-instance-guix
33574 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
33578 Users can implement support for OS providers unbeknownst to Guix by extending
33579 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
33585 (extension ".conf")
33587 (list (ganeti-os-variant
33589 (configuration (plain-file "bar" "this is fine"))))))
33592 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
33593 to a file in the store with contents @code{this is fine}. It also creates
33594 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
33596 Obviously this may not work for all OS providers out there. If you find the
33597 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
33599 The rest of this section documents the various services that are included by
33600 @code{ganeti-service-type}.
33602 @defvr {Scheme Variable} ganeti-noded-service-type
33603 @command{ganeti-noded} is the daemon responsible for node-specific functions
33604 within the Ganeti system. The value of this service must be a
33605 @code{ganeti-noded-configuration} object.
33608 @deftp {Data Type} ganeti-noded-configuration
33609 This is the configuration for the @code{ganeti-noded} service.
33612 @item @code{ganeti} (default: @code{ganeti})
33613 The @code{ganeti} package to use for this service.
33615 @item @code{port} (default: @code{1811})
33616 The TCP port on which the node daemon listens for network requests.
33618 @item @code{address} (default: @code{"0.0.0.0"})
33619 The network address that the daemon will bind to. The default address means
33620 bind to all available addresses.
33622 @item @code{interface} (default: @code{#f})
33623 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
33624 that the daemon will bind to.
33626 @item @code{max-clients} (default: @code{20})
33627 This sets a limit on the maximum number of simultaneous client connections
33628 that the daemon will handle. Connections above this count are accepted, but
33629 no responses will be sent until enough connections have closed.
33631 @item @code{ssl?} (default: @code{#t})
33632 Whether to use SSL/TLS to encrypt network communications. The certificate
33633 is automatically provisioned by the cluster and can be rotated with
33634 @command{gnt-cluster renew-crypto}.
33636 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33637 This can be used to provide a specific encryption key for TLS communications.
33639 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33640 This can be used to provide a specific certificate for TLS communications.
33642 @item @code{debug?} (default: @code{#f})
33643 When true, the daemon performs additional logging for debugging purposes.
33644 Note that this will leak encryption details to the log files, use with caution.
33649 @defvr {Scheme Variable} ganeti-confd-service-type
33650 @command{ganeti-confd} answers queries related to the configuration of a
33651 Ganeti cluster. The purpose of this daemon is to have a highly available
33652 and fast way to query cluster configuration values. It is automatically
33653 active on all @dfn{master candidates}. The value of this service must be a
33654 @code{ganeti-confd-configuration} object.
33658 @deftp {Data Type} ganeti-confd-configuration
33659 This is the configuration for the @code{ganeti-confd} service.
33662 @item @code{ganeti} (default: @code{ganeti})
33663 The @code{ganeti} package to use for this service.
33665 @item @code{port} (default: @code{1814})
33666 The UDP port on which to listen for network requests.
33668 @item @code{address} (default: @code{"0.0.0.0"})
33669 Network address that the daemon will bind to.
33671 @item @code{debug?} (default: @code{#f})
33672 When true, the daemon performs additional logging for debugging purposes.
33677 @defvr {Scheme Variable} ganeti-wconfd-service-type
33678 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
33679 about the cluster configuration and is the only entity that can accept
33680 changes to it. All jobs that need to modify the configuration will do so
33681 by sending appropriate requests to this daemon. It only runs on the
33682 @dfn{master node} and will automatically disable itself on other nodes.
33684 The value of this service must be a
33685 @code{ganeti-wconfd-configuration} object.
33688 @deftp {Data Type} ganeti-wconfd-configuration
33689 This is the configuration for the @code{ganeti-wconfd} service.
33692 @item @code{ganeti} (default: @code{ganeti})
33693 The @code{ganeti} package to use for this service.
33695 @item @code{no-voting?} (default: @code{#f})
33696 The daemon will refuse to start if the majority of cluster nodes does not
33697 agree that it is running on the master node. Set to @code{#t} to start
33698 even if a quorum can not be reached (dangerous, use with caution).
33700 @item @code{debug?} (default: @code{#f})
33701 When true, the daemon performs additional logging for debugging purposes.
33706 @defvr {Scheme Variable} ganeti-luxid-service-type
33707 @command{ganeti-luxid} is a daemon used to answer queries related to the
33708 configuration and the current live state of a Ganeti cluster. Additionally,
33709 it is the authoritative daemon for the Ganeti job queue. Jobs can be
33710 submitted via this daemon and it schedules and starts them.
33712 It takes a @code{ganeti-luxid-configuration} object.
33715 @deftp {Data Type} ganeti-luxid-configuration
33716 This is the configuration for the @code{ganeti-luxid} service.
33719 @item @code{ganeti} (default: @code{ganeti})
33720 The @code{ganeti} package to use for this service.
33722 @item @code{no-voting?} (default: @code{#f})
33723 The daemon will refuse to start if it cannot verify that the majority of
33724 cluster nodes believes that it is running on the master node. Set to
33725 @code{#t} to ignore such checks and start anyway (this can be dangerous).
33727 @item @code{debug?} (default: @code{#f})
33728 When true, the daemon performs additional logging for debugging purposes.
33733 @defvr {Scheme Variable} ganeti-rapi-service-type
33734 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
33735 the master node and can be used to perform cluster actions programmatically
33736 via a JSON-based RPC protocol.
33738 Most query operations are allowed without authentication (unless
33739 @var{require-authentication?} is set), whereas write operations require
33740 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
33741 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
33742 API documentation} for more information.
33744 The value of this service must be a @code{ganeti-rapi-configuration} object.
33747 @deftp {Data Type} ganeti-rapi-configuration
33748 This is the configuration for the @code{ganeti-rapi} service.
33751 @item @code{ganeti} (default: @code{ganeti})
33752 The @code{ganeti} package to use for this service.
33754 @item @code{require-authentication?} (default: @code{#f})
33755 Whether to require authentication even for read-only operations.
33757 @item @code{port} (default: @code{5080})
33758 The TCP port on which to listen to API requests.
33760 @item @code{address} (default: @code{"0.0.0.0"})
33761 The network address that the service will bind to. By default it listens
33762 on all configured addresses.
33764 @item @code{interface} (default: @code{#f})
33765 When set, it must specify a specific network interface such as @code{eth0}
33766 that the daemon will bind to.
33768 @item @code{max-clients} (default: @code{20})
33769 The maximum number of simultaneous client requests to handle. Further
33770 connections are allowed, but no responses are sent until enough connections
33773 @item @code{ssl?} (default: @code{#t})
33774 Whether to use SSL/TLS encryption on the RAPI port.
33776 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33777 This can be used to provide a specific encryption key for TLS communications.
33779 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33780 This can be used to provide a specific certificate for TLS communications.
33782 @item @code{debug?} (default: @code{#f})
33783 When true, the daemon performs additional logging for debugging purposes.
33784 Note that this will leak encryption details to the log files, use with caution.
33789 @defvr {Scheme Variable} ganeti-kvmd-service-type
33790 @command{ganeti-kvmd} is responsible for determining whether a given KVM
33791 instance was shut down by an administrator or a user. Normally Ganeti will
33792 restart an instance that was not stopped through Ganeti itself. If the
33793 cluster option @code{user_shutdown} is true, this daemon monitors the
33794 @code{QMP} socket provided by QEMU and listens for shutdown events, and
33795 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
33796 it shuts down gracefully by itself.
33798 It takes a @code{ganeti-kvmd-configuration} object.
33801 @deftp {Data Type} ganeti-kvmd-configuration
33804 @item @code{ganeti} (default: @code{ganeti})
33805 The @code{ganeti} package to use for this service.
33807 @item @code{debug?} (default: @code{#f})
33808 When true, the daemon performs additional logging for debugging purposes.
33813 @defvr {Scheme Variable} ganeti-mond-service-type
33814 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
33815 functionality. It is responsible for running data collectors and publish the
33816 collected information through a HTTP interface.
33818 It takes a @code{ganeti-mond-configuration} object.
33821 @deftp {Data Type} ganeti-mond-configuration
33824 @item @code{ganeti} (default: @code{ganeti})
33825 The @code{ganeti} package to use for this service.
33827 @item @code{port} (default: @code{1815})
33828 The port on which the daemon will listen.
33830 @item @code{address} (default: @code{"0.0.0.0"})
33831 The network address that the daemon will bind to. By default it binds to all
33832 available interfaces.
33834 @item @code{debug?} (default: @code{#f})
33835 When true, the daemon performs additional logging for debugging purposes.
33840 @defvr {Scheme Variable} ganeti-metad-service-type
33841 @command{ganeti-metad} is an optional daemon that can be used to provide
33842 information about the cluster to instances or OS install scripts.
33844 It takes a @code{ganeti-metad-configuration} object.
33847 @deftp {Data Type} ganeti-metad-configuration
33850 @item @code{ganeti} (default: @code{ganeti})
33851 The @code{ganeti} package to use for this service.
33853 @item @code{port} (default: @code{80})
33854 The port on which the daemon will listen.
33856 @item @code{address} (default: @code{#f})
33857 If set, the daemon will bind to this address only. If left unset, the behavior
33858 depends on the cluster configuration.
33860 @item @code{debug?} (default: @code{#f})
33861 When true, the daemon performs additional logging for debugging purposes.
33866 @defvr {Scheme Variable} ganeti-watcher-service-type
33867 @command{ganeti-watcher} is a script designed to run periodically and ensure
33868 the health of a cluster. It will automatically restart instances that have
33869 stopped without Ganeti's consent, and repairs DRBD links in case a node has
33870 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
33871 that are not running. If the cluster parameter @code{ensure_node_health}
33872 is set, the watcher will also shutdown instances and DRBD devices if the
33873 node it is running on is declared offline by known master candidates.
33875 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
33877 The service takes a @code{ganeti-watcher-configuration} object.
33880 @deftp {Data Type} ganeti-watcher-configuration
33883 @item @code{ganeti} (default: @code{ganeti})
33884 The @code{ganeti} package to use for this service.
33886 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
33887 How often to run the script. The default is every five minutes.
33889 @item @code{rapi-ip} (default: @code{#f})
33890 This option needs to be specified only if the RAPI daemon is configured to use
33891 a particular interface or address. By default the cluster address is used.
33893 @item @code{job-age} (default: @code{(* 6 3600)})
33894 Archive cluster jobs older than this age, specified in seconds. The default
33895 is 6 hours. This keeps @command{gnt-job list} manageable.
33897 @item @code{verify-disks?} (default: @code{#t})
33898 If this is @code{#f}, the watcher will not try to repair broken DRBD links
33899 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
33902 @item @code{debug?} (default: @code{#f})
33903 When @code{#t}, the script performs additional logging for debugging purposes.
33908 @defvr {Scheme Variable} ganeti-cleaner-service-type
33909 @command{ganeti-cleaner} is a script designed to run periodically and remove
33910 old files from the cluster. This service type controls two @dfn{cron jobs}:
33911 one intended for the master node that permanently purges old cluster jobs,
33912 and one intended for every node that removes expired X509 certificates, keys,
33913 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
33914 it is safe to include even on non-master nodes as it will disable itself as
33917 It takes a @code{ganeti-cleaner-configuration} object.
33920 @deftp {Data Type} ganeti-cleaner-configuration
33923 @item @code{ganeti} (default: @code{ganeti})
33924 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
33926 @item @code{master-schedule} (default: @code{"45 1 * * *"})
33927 How often to run the master cleaning job. The default is once per day, at
33930 @item @code{node-schedule} (default: @code{"45 2 * * *"})
33931 How often to run the node cleaning job. The default is once per day, at
33937 @node Version Control Services
33938 @subsection Version Control Services
33940 The @code{(gnu services version-control)} module provides a service to
33941 allow remote access to local Git repositories. There are three options:
33942 the @code{git-daemon-service}, which provides access to repositories via
33943 the @code{git://} unsecured TCP-based protocol, extending the
33944 @code{nginx} web server to proxy some requests to
33945 @code{git-http-backend}, or providing a web interface with
33946 @code{cgit-service-type}.
33948 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
33950 Return a service that runs @command{git daemon}, a simple TCP server to
33951 expose repositories over the Git protocol for anonymous access.
33953 The optional @var{config} argument should be a
33954 @code{<git-daemon-configuration>} object, by default it allows read-only
33955 access to exported@footnote{By creating the magic file
33956 @file{git-daemon-export-ok} in the repository directory.} repositories under
33961 @deftp {Data Type} git-daemon-configuration
33962 Data type representing the configuration for @code{git-daemon-service}.
33965 @item @code{package} (default: @code{git})
33966 Package object of the Git distributed version control system.
33968 @item @code{export-all?} (default: @code{#f})
33969 Whether to allow access for all Git repositories, even if they do not
33970 have the @file{git-daemon-export-ok} file.
33972 @item @code{base-path} (default: @file{/srv/git})
33973 Whether to remap all the path requests as relative to the given path.
33974 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
33975 @samp{example.com}, then if you later try to pull
33976 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
33977 path as @file{/srv/git/hello.git}.
33979 @item @code{user-path} (default: @code{#f})
33980 Whether to allow @code{~user} notation to be used in requests. When
33981 specified with empty string, requests to
33982 @indicateurl{git://host/~alice/foo} is taken as a request to access
33983 @code{foo} repository in the home directory of user @code{alice}. If
33984 @code{(user-path "@var{path}")} is specified, the same request is taken
33985 as a request to access @file{@var{path}/foo} repository in the home
33986 directory of user @code{alice}.
33988 @item @code{listen} (default: @code{'()})
33989 Whether to listen on specific IP addresses or hostnames, defaults to
33992 @item @code{port} (default: @code{#f})
33993 Whether to listen on an alternative port, which defaults to 9418.
33995 @item @code{whitelist} (default: @code{'()})
33996 If not empty, only allow access to this list of directories.
33998 @item @code{extra-options} (default: @code{'()})
33999 Extra options will be passed to @command{git daemon}, please run
34000 @command{man git-daemon} for more information.
34005 The @code{git://} protocol lacks authentication. When you pull from a
34006 repository fetched via @code{git://}, you don't know whether the data you
34007 receive was modified or is even coming from the specified host, and your
34008 connection is subject to eavesdropping. It's better to use an authenticated
34009 and encrypted transport, such as @code{https}. Although Git allows you
34010 to serve repositories using unsophisticated file-based web servers,
34011 there is a faster protocol implemented by the @code{git-http-backend}
34012 program. This program is the back-end of a proper Git web service. It
34013 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
34014 on running the necessary @code{fcgiwrap} daemon.
34016 Guix has a separate configuration data type for serving Git repositories
34019 @deftp {Data Type} git-http-configuration
34020 Data type representing the configuration for a future
34021 @code{git-http-service-type}; can currently be used to configure Nginx
34022 through @code{git-http-nginx-location-configuration}.
34025 @item @code{package} (default: @var{git})
34026 Package object of the Git distributed version control system.
34028 @item @code{git-root} (default: @file{/srv/git})
34029 Directory containing the Git repositories to expose to the world.
34031 @item @code{export-all?} (default: @code{#f})
34032 Whether to expose access for all Git repositories in @var{git-root},
34033 even if they do not have the @file{git-daemon-export-ok} file.
34035 @item @code{uri-path} (default: @samp{/git/})
34036 Path prefix for Git access. With the default @samp{/git/} prefix, this
34037 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
34038 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
34039 with this prefix are not passed on to this Git instance.
34041 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
34042 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
34047 There is no @code{git-http-service-type}, currently; instead you can
34048 create an @code{nginx-location-configuration} from a
34049 @code{git-http-configuration} and then add that location to a web
34052 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
34053 [config=(git-http-configuration)]
34054 Compute an @code{nginx-location-configuration} that corresponds to the
34055 given Git http configuration. An example nginx service definition to
34056 serve the default @file{/srv/git} over HTTPS might be:
34059 (service nginx-service-type
34060 (nginx-configuration
34063 (nginx-server-configuration
34064 (listen '("443 ssl"))
34065 (server-name "git.my-host.org")
34067 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
34068 (ssl-certificate-key
34069 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
34072 (git-http-nginx-location-configuration
34073 (git-http-configuration (uri-path "/"))))))))))
34076 This example assumes that you are using Let's Encrypt to get your TLS
34077 certificate. @xref{Certificate Services}. The default @code{certbot}
34078 service will redirect all HTTP traffic on @code{git.my-host.org} to
34079 HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
34080 system services. @xref{Web Services}.
34083 @subsubheading Cgit Service
34085 @cindex Cgit service
34086 @cindex Git, web interface
34087 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
34088 repositories written in C.
34090 The following example will configure the service with default values.
34091 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
34094 (service cgit-service-type)
34097 The @code{file-object} type designates either a file-like object
34098 (@pxref{G-Expressions, file-like objects}) or a string.
34100 @c %start of fragment
34102 Available @code{cgit-configuration} fields are:
34104 @deftypevr {@code{cgit-configuration} parameter} package package
34109 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
34110 NGINX configuration.
34114 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
34115 Specifies a command which will be invoked to format the content of about
34116 pages (both top-level and for each repository).
34118 Defaults to @samp{""}.
34122 @deftypevr {@code{cgit-configuration} parameter} string agefile
34123 Specifies a path, relative to each repository path, which can be used to
34124 specify the date and time of the youngest commit in the repository.
34126 Defaults to @samp{""}.
34130 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
34131 Specifies a command that will be invoked for authenticating repository
34134 Defaults to @samp{""}.
34138 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
34139 Flag which, when set to @samp{age}, enables date ordering in the branch
34140 ref list, and when set @samp{name} enables ordering by branch name.
34142 Defaults to @samp{"name"}.
34146 @deftypevr {@code{cgit-configuration} parameter} string cache-root
34147 Path used to store the cgit cache entries.
34149 Defaults to @samp{"/var/cache/cgit"}.
34153 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
34154 Number which specifies the time-to-live, in minutes, for the cached
34155 version of repository pages accessed with a fixed SHA1.
34157 Defaults to @samp{-1}.
34161 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
34162 Number which specifies the time-to-live, in minutes, for the cached
34163 version of repository pages accessed without a fixed SHA1.
34165 Defaults to @samp{5}.
34169 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
34170 Number which specifies the time-to-live, in minutes, for the cached
34171 version of the repository summary page.
34173 Defaults to @samp{5}.
34177 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
34178 Number which specifies the time-to-live, in minutes, for the cached
34179 version of the repository index page.
34181 Defaults to @samp{5}.
34185 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
34186 Number which specifies the time-to-live, in minutes, for the result of
34187 scanning a path for Git repositories.
34189 Defaults to @samp{15}.
34193 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
34194 Number which specifies the time-to-live, in minutes, for the cached
34195 version of the repository about page.
34197 Defaults to @samp{15}.
34201 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
34202 Number which specifies the time-to-live, in minutes, for the cached
34203 version of snapshots.
34205 Defaults to @samp{5}.
34209 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
34210 The maximum number of entries in the cgit cache. When set to @samp{0},
34211 caching is disabled.
34213 Defaults to @samp{0}.
34217 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
34218 Sort items in the repo list case sensitively.
34220 Defaults to @samp{#t}.
34224 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
34225 List of common prefixes which, when combined with a repository URL,
34226 generates valid clone URLs for the repository.
34228 Defaults to @samp{()}.
34232 @deftypevr {@code{cgit-configuration} parameter} list clone-url
34233 List of @code{clone-url} templates.
34235 Defaults to @samp{()}.
34239 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
34240 Command which will be invoked to format commit messages.
34242 Defaults to @samp{""}.
34246 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
34247 Flag which, when set to @samp{date}, enables strict date ordering in the
34248 commit log, and when set to @samp{topo} enables strict topological
34251 Defaults to @samp{"git log"}.
34255 @deftypevr {@code{cgit-configuration} parameter} file-object css
34256 URL which specifies the css document to include in all cgit pages.
34258 Defaults to @samp{"/share/cgit/cgit.css"}.
34262 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
34263 Specifies a command which will be invoked to format names and email
34264 address of committers, authors, and taggers, as represented in various
34265 places throughout the cgit interface.
34267 Defaults to @samp{""}.
34271 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
34272 Flag which, when set to @samp{#t}, will make cgit generate a HTML
34273 fragment suitable for embedding in other HTML pages.
34275 Defaults to @samp{#f}.
34279 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
34280 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
34281 commit history graph to the left of the commit messages in the
34282 repository log page.
34284 Defaults to @samp{#f}.
34288 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
34289 Flag which, when set to @samp{#t}, allows all filter settings to be
34290 overridden in repository-specific cgitrc files.
34292 Defaults to @samp{#f}.
34296 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
34297 Flag which, when set to @samp{#t}, allows users to follow a file in the
34300 Defaults to @samp{#f}.
34304 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
34305 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
34308 Defaults to @samp{#t}.
34312 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
34313 Flag which, when set to @samp{#t}, will make cgit generate extra links
34314 "summary", "commit", "tree" for each repo in the repository index.
34316 Defaults to @samp{#f}.
34320 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
34321 Flag which, when set to @samp{#t}, will make cgit display the owner of
34322 each repo in the repository index.
34324 Defaults to @samp{#t}.
34328 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
34329 Flag which, when set to @samp{#t}, will make cgit print the number of
34330 modified files for each commit on the repository log page.
34332 Defaults to @samp{#f}.
34336 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
34337 Flag which, when set to @samp{#t}, will make cgit print the number of
34338 added and removed lines for each commit on the repository log page.
34340 Defaults to @samp{#f}.
34344 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
34345 Flag which, when set to @code{#t}, will make cgit display remote
34346 branches in the summary and refs views.
34348 Defaults to @samp{#f}.
34352 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
34353 Flag which, when set to @code{1}, will make cgit use the subject of the
34354 parent commit as link text when generating links to parent commits in
34357 Defaults to @samp{#f}.
34361 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
34362 Flag which, when set to @samp{#t}, will make cgit use the subject of the
34363 parent commit as link text when generating links to parent commits in
34366 Defaults to @samp{#f}.
34370 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
34371 Flag which, when set to @samp{#t}, will make cgit generate linenumber
34372 links for plaintext blobs printed in the tree view.
34374 Defaults to @samp{#t}.
34378 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
34379 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
34380 set any repo specific settings.
34382 Defaults to @samp{#f}.
34386 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
34387 URL used as link to a shortcut icon for cgit.
34389 Defaults to @samp{"/favicon.ico"}.
34393 @deftypevr {@code{cgit-configuration} parameter} string footer
34394 The content of the file specified with this option will be included
34395 verbatim at the bottom of all pages (i.e.@: it replaces the standard
34396 "generated by..."@: message).
34398 Defaults to @samp{""}.
34402 @deftypevr {@code{cgit-configuration} parameter} string head-include
34403 The content of the file specified with this option will be included
34404 verbatim in the HTML HEAD section on all pages.
34406 Defaults to @samp{""}.
34410 @deftypevr {@code{cgit-configuration} parameter} string header
34411 The content of the file specified with this option will be included
34412 verbatim at the top of all pages.
34414 Defaults to @samp{""}.
34418 @deftypevr {@code{cgit-configuration} parameter} file-object include
34419 Name of a configfile to include before the rest of the current config-
34422 Defaults to @samp{""}.
34426 @deftypevr {@code{cgit-configuration} parameter} string index-header
34427 The content of the file specified with this option will be included
34428 verbatim above the repository index.
34430 Defaults to @samp{""}.
34434 @deftypevr {@code{cgit-configuration} parameter} string index-info
34435 The content of the file specified with this option will be included
34436 verbatim below the heading on the repository index page.
34438 Defaults to @samp{""}.
34442 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
34443 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
34444 in the servers timezone.
34446 Defaults to @samp{#f}.
34450 @deftypevr {@code{cgit-configuration} parameter} file-object logo
34451 URL which specifies the source of an image which will be used as a logo
34454 Defaults to @samp{"/share/cgit/cgit.png"}.
34458 @deftypevr {@code{cgit-configuration} parameter} string logo-link
34459 URL loaded when clicking on the cgit logo image.
34461 Defaults to @samp{""}.
34465 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
34466 Command which will be invoked to format the Owner column of the main
34469 Defaults to @samp{""}.
34473 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
34474 Number of items to display in atom feeds view.
34476 Defaults to @samp{10}.
34480 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
34481 Number of entries to list per page in "log" view.
34483 Defaults to @samp{50}.
34487 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
34488 Number of commit message characters to display in "log" view.
34490 Defaults to @samp{80}.
34494 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
34495 Specifies the number of entries to list per page on the repository index
34498 Defaults to @samp{50}.
34502 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
34503 Specifies the maximum number of repo description characters to display
34504 on the repository index page.
34506 Defaults to @samp{80}.
34510 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
34511 Specifies the maximum size of a blob to display HTML for in KBytes.
34513 Defaults to @samp{0}.
34517 @deftypevr {@code{cgit-configuration} parameter} string max-stats
34518 Maximum statistics period. Valid values are @samp{week},@samp{month},
34519 @samp{quarter} and @samp{year}.
34521 Defaults to @samp{""}.
34525 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
34526 Mimetype for the specified filename extension.
34528 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
34529 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
34530 "image/png") (svg "image/svg+xml"))}.
34534 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
34535 Specifies the file to use for automatic mimetype lookup.
34537 Defaults to @samp{""}.
34541 @deftypevr {@code{cgit-configuration} parameter} string module-link
34542 Text which will be used as the formatstring for a hyperlink when a
34543 submodule is printed in a directory listing.
34545 Defaults to @samp{""}.
34549 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
34550 If set to the value @samp{#t} caching will be disabled.
34552 Defaults to @samp{#f}.
34556 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
34557 If set to @samp{#t} showing full author email addresses will be
34560 Defaults to @samp{#f}.
34564 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
34565 Flag which, when set to @samp{#t}, will make cgit omit the standard
34566 header on all pages.
34568 Defaults to @samp{#f}.
34572 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
34573 A list of subdirectories inside of @code{repository-directory}, relative
34574 to it, that should loaded as Git repositories. An empty list means that
34575 all subdirectories will be loaded.
34577 Defaults to @samp{()}.
34581 @deftypevr {@code{cgit-configuration} parameter} file-object readme
34582 Text which will be used as default value for @code{cgit-repo-readme}.
34584 Defaults to @samp{""}.
34588 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
34589 If set to @code{#t} and @code{repository-directory} is enabled, if any
34590 repositories are found with a suffix of @code{.git}, this suffix will be
34591 removed for the URL and name.
34593 Defaults to @samp{#f}.
34597 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
34598 Maximum number of files to consider when detecting renames.
34600 Defaults to @samp{-1}.
34604 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
34605 The way in which repositories in each section are sorted.
34607 Defaults to @samp{""}.
34611 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
34612 Text used as content for the @code{robots} meta-tag.
34614 Defaults to @samp{("noindex" "nofollow")}.
34618 @deftypevr {@code{cgit-configuration} parameter} string root-desc
34619 Text printed below the heading on the repository index page.
34621 Defaults to @samp{"a fast webinterface for the git dscm"}.
34625 @deftypevr {@code{cgit-configuration} parameter} string root-readme
34626 The content of the file specified with this option will be included
34627 verbatim below the ``about'' link on the repository index page.
34629 Defaults to @samp{""}.
34633 @deftypevr {@code{cgit-configuration} parameter} string root-title
34634 Text printed as heading on the repository index page.
34636 Defaults to @samp{""}.
34640 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
34641 If set to @samp{#t} and repository-directory is enabled,
34642 repository-directory will recurse into directories whose name starts
34643 with a period. Otherwise, repository-directory will stay away from such
34644 directories, considered as ``hidden''. Note that this does not apply to
34645 the @file{.git} directory in non-bare repos.
34647 Defaults to @samp{#f}.
34651 @deftypevr {@code{cgit-configuration} parameter} list snapshots
34652 Text which specifies the default set of snapshot formats that cgit
34653 generates links for.
34655 Defaults to @samp{()}.
34659 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
34660 Name of the directory to scan for repositories (represents
34663 Defaults to @samp{"/srv/git"}.
34667 @deftypevr {@code{cgit-configuration} parameter} string section
34668 The name of the current repository section - all repositories defined
34669 after this option will inherit the current section name.
34671 Defaults to @samp{""}.
34675 @deftypevr {@code{cgit-configuration} parameter} string section-sort
34676 Flag which, when set to @samp{1}, will sort the sections on the
34677 repository listing by name.
34679 Defaults to @samp{""}.
34683 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
34684 A number which, if defined prior to repository-directory, specifies how
34685 many path elements from each repo path to use as a default section name.
34687 Defaults to @samp{0}.
34691 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
34692 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
34695 Defaults to @samp{#f}.
34699 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
34700 Specifies a command which will be invoked to format plaintext blobs in
34703 Defaults to @samp{""}.
34707 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
34708 Specifies the number of branches to display in the repository ``summary''
34711 Defaults to @samp{10}.
34715 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
34716 Specifies the number of log entries to display in the repository
34719 Defaults to @samp{10}.
34723 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
34724 Specifies the number of tags to display in the repository ``summary''
34727 Defaults to @samp{10}.
34731 @deftypevr {@code{cgit-configuration} parameter} string strict-export
34732 Filename which, if specified, needs to be present within the repository
34733 for cgit to allow access to that repository.
34735 Defaults to @samp{""}.
34739 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
34740 URL which, if specified, will be used as root for all cgit links.
34742 Defaults to @samp{"/"}.
34746 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
34747 A list of @dfn{cgit-repo} records to use with config.
34749 Defaults to @samp{()}.
34751 Available @code{repository-cgit-configuration} fields are:
34753 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
34754 A mask of snapshot formats for this repo that cgit generates links for,
34755 restricted by the global @code{snapshots} setting.
34757 Defaults to @samp{()}.
34761 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
34762 Override the default @code{source-filter}.
34764 Defaults to @samp{""}.
34768 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
34769 The relative URL used to access the repository.
34771 Defaults to @samp{""}.
34775 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
34776 Override the default @code{about-filter}.
34778 Defaults to @samp{""}.
34782 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
34783 Flag which, when set to @samp{age}, enables date ordering in the branch
34784 ref list, and when set to @samp{name} enables ordering by branch name.
34786 Defaults to @samp{""}.
34790 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
34791 A list of URLs which can be used to clone repo.
34793 Defaults to @samp{()}.
34797 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
34798 Override the default @code{commit-filter}.
34800 Defaults to @samp{""}.
34804 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
34805 Flag which, when set to @samp{date}, enables strict date ordering in the
34806 commit log, and when set to @samp{topo} enables strict topological
34809 Defaults to @samp{""}.
34813 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
34814 The name of the default branch for this repository. If no such branch
34815 exists in the repository, the first branch name (when sorted) is used as
34816 default instead. By default branch pointed to by HEAD, or ``master'' if
34817 there is no suitable HEAD.
34819 Defaults to @samp{""}.
34823 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
34824 The value to show as repository description.
34826 Defaults to @samp{""}.
34830 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
34831 The value to show as repository homepage.
34833 Defaults to @samp{""}.
34837 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
34838 Override the default @code{email-filter}.
34840 Defaults to @samp{""}.
34844 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
34845 A flag which can be used to disable the global setting
34846 @code{enable-commit-graph?}.
34848 Defaults to @samp{disabled}.
34852 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
34853 A flag which can be used to disable the global setting
34854 @code{enable-log-filecount?}.
34856 Defaults to @samp{disabled}.
34860 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
34861 A flag which can be used to disable the global setting
34862 @code{enable-log-linecount?}.
34864 Defaults to @samp{disabled}.
34868 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
34869 Flag which, when set to @code{#t}, will make cgit display remote
34870 branches in the summary and refs views.
34872 Defaults to @samp{disabled}.
34876 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
34877 A flag which can be used to override the global setting
34878 @code{enable-subject-links?}.
34880 Defaults to @samp{disabled}.
34884 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
34885 A flag which can be used to override the global setting
34886 @code{enable-html-serving?}.
34888 Defaults to @samp{disabled}.
34892 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
34893 Flag which, when set to @code{#t}, hides the repository from the
34896 Defaults to @samp{#f}.
34900 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
34901 Flag which, when set to @samp{#t}, ignores the repository.
34903 Defaults to @samp{#f}.
34907 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
34908 URL which specifies the source of an image which will be used as a logo
34909 on this repo’s pages.
34911 Defaults to @samp{""}.
34915 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
34916 URL loaded when clicking on the cgit logo image.
34918 Defaults to @samp{""}.
34922 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
34923 Override the default @code{owner-filter}.
34925 Defaults to @samp{""}.
34929 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
34930 Text which will be used as the formatstring for a hyperlink when a
34931 submodule is printed in a directory listing. The arguments for the
34932 formatstring are the path and SHA1 of the submodule commit.
34934 Defaults to @samp{""}.
34938 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
34939 Text which will be used as the formatstring for a hyperlink when a
34940 submodule with the specified subdirectory path is printed in a directory
34943 Defaults to @samp{()}.
34947 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
34948 Override the default maximum statistics period.
34950 Defaults to @samp{""}.
34954 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
34955 The value to show as repository name.
34957 Defaults to @samp{""}.
34961 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
34962 A value used to identify the owner of the repository.
34964 Defaults to @samp{""}.
34968 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
34969 An absolute path to the repository directory.
34971 Defaults to @samp{""}.
34975 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
34976 A path (relative to repo) which specifies a file to include verbatim as
34977 the ``About'' page for this repo.
34979 Defaults to @samp{""}.
34983 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
34984 The name of the current repository section - all repositories defined
34985 after this option will inherit the current section name.
34987 Defaults to @samp{""}.
34991 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
34992 Extra options will be appended to cgitrc file.
34994 Defaults to @samp{()}.
35000 @deftypevr {@code{cgit-configuration} parameter} list extra-options
35001 Extra options will be appended to cgitrc file.
35003 Defaults to @samp{()}.
35008 @c %end of fragment
35010 However, it could be that you just want to get a @code{cgitrc} up and
35011 running. In that case, you can pass an @code{opaque-cgit-configuration}
35012 as a record to @code{cgit-service-type}. As its name indicates, an
35013 opaque configuration does not have easy reflective capabilities.
35015 Available @code{opaque-cgit-configuration} fields are:
35017 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
35021 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
35022 The contents of the @code{cgitrc}, as a string.
35025 For example, if your @code{cgitrc} is just the empty string, you
35026 could instantiate a cgit service like this:
35029 (service cgit-service-type
35030 (opaque-cgit-configuration
35034 @subsubheading Gitolite Service
35036 @cindex Gitolite service
35037 @cindex Git, hosting
35038 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
35039 repositories on a central server.
35041 Gitolite can handle multiple repositories and users, and supports flexible
35042 configuration of the permissions for the users on the repositories.
35044 The following example will configure Gitolite using the default @code{git}
35045 user, and the provided SSH public key.
35048 (service gitolite-service-type
35049 (gitolite-configuration
35050 (admin-pubkey (plain-file
35052 "ssh-rsa AAAA... guix@@example.com"))))
35055 Gitolite is configured through a special admin repository which you can clone,
35056 for example, if you setup Gitolite on @code{example.com}, you would run the
35057 following command to clone the admin repository.
35060 git clone git@@example.com:gitolite-admin
35063 When the Gitolite service is activated, the provided @code{admin-pubkey} will
35064 be inserted in to the @file{keydir} directory in the gitolite-admin
35065 repository. If this results in a change in the repository, it will be
35066 committed using the message ``gitolite setup by GNU Guix''.
35068 @deftp {Data Type} gitolite-configuration
35069 Data type representing the configuration for @code{gitolite-service-type}.
35072 @item @code{package} (default: @var{gitolite})
35073 Gitolite package to use.
35075 @item @code{user} (default: @var{git})
35076 User to use for Gitolite. This will be user that you use when accessing
35079 @item @code{group} (default: @var{git})
35080 Group to use for Gitolite.
35082 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
35083 Directory in which to store the Gitolite configuration and repositories.
35085 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
35086 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
35087 representing the configuration for Gitolite.
35089 @item @code{admin-pubkey} (default: @var{#f})
35090 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
35091 setup Gitolite. This will be inserted in to the @file{keydir} directory
35092 within the gitolite-admin repository.
35094 To specify the SSH key as a string, use the @code{plain-file} function.
35097 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
35103 @deftp {Data Type} gitolite-rc-file
35104 Data type representing the Gitolite RC file.
35107 @item @code{umask} (default: @code{#o0077})
35108 This controls the permissions Gitolite sets on the repositories and their
35111 A value like @code{#o0027} will give read access to the group used by Gitolite
35112 (by default: @code{git}). This is necessary when using Gitolite with software
35113 like cgit or gitweb.
35115 @item @code{unsafe-pattern} (default: @code{#f})
35116 An optional Perl regular expression for catching unsafe configurations in
35117 the configuration file. See
35118 @uref{https://gitolite.com/gitolite/git-config.html#compensating-for-unsafe_patt,
35119 Gitolite's documentation} for more information.
35121 When the value is not @code{#f}, it should be a string containing a Perl
35122 regular expression, such as @samp{"[`~#\$\&()|;<>]"}, which is the default
35123 value used by gitolite. It rejects any special character in configuration
35124 that might be interpreted by a shell, which is useful when sharing the
35125 administration burden with other people that do not otherwise have shell
35126 access on the server.
35128 @item @code{git-config-keys} (default: @code{""})
35129 Gitolite allows you to set git config values using the @samp{config}
35130 keyword. This setting allows control over the config keys to accept.
35132 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
35133 Set the role names allowed to be used by users running the perms command.
35135 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
35136 This setting controls the commands and features to enable within Gitolite.
35142 @subsubheading Gitile Service
35144 @cindex Gitile service
35146 @uref{https://git.lepiller.eu/gitile, Gitile} is a Git forge for viewing
35147 public git repository contents from a web browser.
35149 Gitile works best in collaboration with Gitolite, and will serve the public
35150 repositories from Gitolite by default. The service should listen only on
35151 a local port, and a webserver should be configured to serve static resources.
35152 The gitile service provides an easy way to extend the Nginx service for
35153 that purpose (@pxref{NGINX}).
35155 The following example will configure Gitile to serve repositories from a
35156 custom location, with some default messages for the home page and the
35160 (service gitile-service-type
35161 (gitile-configuration
35162 (repositories "/srv/git")
35163 (base-git-url "https://myweb.site/git")
35164 (index-title "My git repositories")
35165 (intro '((p "This is all my public work!")))
35166 (footer '((p "This is the end")))
35167 (nginx-server-block
35168 (nginx-server-configuration
35170 "/etc/letsencrypt/live/myweb.site/fullchain.pem")
35171 (ssl-certificate-key
35172 "/etc/letsencrypt/live/myweb.site/privkey.pem")
35173 (listen '("443 ssl http2" "[::]:443 ssl http2"))
35176 ;; Allow for https anonymous fetch on /git/ urls.
35177 (git-http-nginx-location-configuration
35178 (git-http-configuration
35180 (git-root "/var/lib/gitolite/repositories")))))))))
35183 In addition to the configuration record, you should configure your git
35184 repositories to contain some optional information. First, your public
35185 repositories need to contain the @file{git-daemon-export-ok} magic file
35186 that allows Git to export the repository. Gitile uses the presence of this
35187 file to detect public repositories it should make accessible. To do so with
35188 Gitolite for instance, modify your @file{conf/gitolite.conf} to include
35189 this in the repositories you want to make public:
35196 In addition, Gitile can read the repository configuration to display more
35197 information on the repository. Gitile uses the gitweb namespace for its
35198 configuration. As an example, you can use the following in your
35199 @file{conf/gitolite.conf}:
35204 desc = A long description, optionally with <i>HTML</i>, shown on the index page
35205 config gitweb.name = The Foo Project
35206 config gitweb.synopsis = A short description, shown on the main page of the project
35209 Do not forget to commit and push these changes once you are satisfied. You
35210 may need to change your gitolite configuration to allow the previous
35211 configuration options to be set. One way to do that is to add the
35212 following service definition:
35215 (service gitolite-service-type
35216 (gitolite-configuration
35217 (admin-pubkey (local-file "key.pub"))
35221 ;; Allow to set any configuration key
35222 (git-config-keys ".*")
35223 ;; Allow any text as a valid configuration value
35224 (unsafe-patt "^$")))))
35227 @deftp {Data Type} gitile-configuration
35228 Data type representing the configuration for @code{gitile-service-type}.
35231 @item @code{package} (default: @var{gitile})
35232 Gitile package to use.
35234 @item @code{host} (default: @code{"localhost"})
35235 The host on which gitile is listening.
35237 @item @code{port} (default: @code{8080})
35238 The port on which gitile is listening.
35240 @item @code{database} (default: @code{"/var/lib/gitile/gitile-db.sql"})
35241 The location of the database.
35243 @item @code{repositories} (default: @code{"/var/lib/gitolite/repositories"})
35244 The location of the repositories. Note that only public repositories will
35245 be shown by Gitile. To make a repository public, add an empty
35246 @file{git-daemon-export-ok} file at the root of that repository.
35248 @item @code{base-git-url}
35249 The base git url that will be used to show clone commands.
35251 @item @code{index-title} (default: @code{"Index"})
35252 The page title for the index page that lists all the available repositories.
35254 @item @code{intro} (default: @code{'()})
35255 The intro content, as a list of sxml expressions. This is shown above the list
35256 of repositories, on the index page.
35258 @item @code{footer} (default: @code{'()})
35259 The footer content, as a list of sxml expressions. This is shown on every
35260 page served by Gitile.
35262 @item @code{nginx-server-block}
35263 An nginx server block that will be extended and used as a reverse proxy by
35264 Gitile to serve its pages, and as a normal web server to serve its assets.
35266 You can use this block to add more custom URLs to your domain, such as a
35267 @code{/git/} URL for anonymous clones, or serving any other files you would
35273 @node Game Services
35274 @subsection Game Services
35276 @subsubheading The Battle for Wesnoth Service
35278 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
35279 based tactical strategy game, with several single player campaigns, and
35280 multiplayer games (both networked and local).
35282 @defvar {Scheme Variable} wesnothd-service-type
35283 Service type for the wesnothd service. Its value must be a
35284 @code{wesnothd-configuration} object. To run wesnothd in the default
35285 configuration, instantiate it as:
35288 (service wesnothd-service-type)
35292 @deftp {Data Type} wesnothd-configuration
35293 Data type representing the configuration of @command{wesnothd}.
35296 @item @code{package} (default: @code{wesnoth-server})
35297 The wesnoth server package to use.
35299 @item @code{port} (default: @code{15000})
35300 The port to bind the server to.
35305 @node PAM Mount Service
35306 @subsection PAM Mount Service
35309 The @code{(gnu services pam-mount)} module provides a service allowing
35310 users to mount volumes when they log in. It should be able to mount any
35311 volume format supported by the system.
35313 @defvar {Scheme Variable} pam-mount-service-type
35314 Service type for PAM Mount support.
35317 @deftp {Data Type} pam-mount-configuration
35318 Data type representing the configuration of PAM Mount.
35320 It takes the following parameters:
35324 The configuration rules that will be used to generate
35325 @file{/etc/security/pam_mount.conf.xml}.
35327 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
35328 Guile Reference Manual}), and the default ones don't mount anything for
35332 `((debug (@@ (enable "0")))
35333 (mntoptions (@@ (allow ,(string-join
35334 '("nosuid" "nodev" "loop"
35335 "encryption" "fsck" "nonempty"
35336 "allow_root" "allow_other")
35338 (mntoptions (@@ (require "nosuid,nodev")))
35339 (logout (@@ (wait "0")
35343 (mkmountpoint (@@ (enable "1")
35347 Some @code{volume} elements must be added to automatically mount volumes
35348 at login. Here's an example allowing the user @code{alice} to mount her
35349 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
35350 the partition where he stores his data:
35353 (define pam-mount-rules
35354 `((debug (@@ (enable "0")))
35355 (volume (@@ (user "alice")
35358 (mountpoint "/home/alice")))
35359 (volume (@@ (user "bob")
35362 (mountpoint "/home/bob/data")
35363 (options "defaults,autodefrag,compress")))
35364 (mntoptions (@@ (allow ,(string-join
35365 '("nosuid" "nodev" "loop"
35366 "encryption" "fsck" "nonempty"
35367 "allow_root" "allow_other")
35369 (mntoptions (@@ (require "nosuid,nodev")))
35370 (logout (@@ (wait "0")
35374 (mkmountpoint (@@ (enable "1")
35375 (remove "true")))))
35377 (service pam-mount-service-type
35378 (pam-mount-configuration
35379 (rules pam-mount-rules)))
35382 The complete list of possible options can be found in the man page for
35383 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
35388 @node Guix Services
35389 @subsection Guix Services
35391 @subsubheading Guix Build Coordinator
35392 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
35393 Coordinator} aids in distributing derivation builds among machines
35394 running an @dfn{agent}. The build daemon is still used to build the
35395 derivations, but the Guix Build Coordinator manages allocating builds
35396 and working with the results.
35398 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
35399 more connected @dfn{agent} processes. The coordinator process handles
35400 clients submitting builds, and allocating builds to agents. The agent
35401 processes talk to a build daemon to actually perform the builds, then
35402 send the results back to the coordinator.
35404 There is a script to run the coordinator component of the Guix Build
35405 Coordinator, but the Guix service uses a custom Guile script instead, to
35406 provide better integration with G-expressions used in the configuration.
35408 @defvar {Scheme Variable} guix-build-coordinator-service-type
35409 Service type for the Guix Build Coordinator. Its value must be a
35410 @code{guix-build-coordinator-configuration} object.
35413 @deftp {Data Type} guix-build-coordinator-configuration
35414 Data type representing the configuration of the Guix Build Coordinator.
35417 @item @code{package} (default: @code{guix-build-coordinator})
35418 The Guix Build Coordinator package to use.
35420 @item @code{user} (default: @code{"guix-build-coordinator"})
35421 The system user to run the service as.
35423 @item @code{group} (default: @code{"guix-build-coordinator"})
35424 The system group to run the service as.
35426 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
35427 The URI to use for the database.
35429 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
35430 The URI describing how to listen to requests from agent processes.
35432 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
35433 The URI describing how to listen to requests from clients. The client
35434 API allows submitting builds and currently isn't authenticated, so take
35435 care when configuring this value.
35437 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
35438 A G-expression for the allocation strategy to be used. This is a
35439 procedure that takes the datastore as an argument and populates the
35440 allocation plan in the database.
35442 @item @code{hooks} (default: @var{'()})
35443 An association list of hooks. These provide a way to execute arbitrary
35444 code upon certain events, like a build result being processed.
35446 @item @code{parallel-hooks} (default: @var{'()})
35447 Hooks can be configured to run in parallel. This parameter is an
35448 association list of hooks to do in parallel, where the key is the symbol
35449 for the hook and the value is the number of threads to run.
35451 @item @code{guile} (default: @code{guile-3.0-latest})
35452 The Guile package with which to run the Guix Build Coordinator.
35457 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
35458 Service type for a Guix Build Coordinator agent. Its value must be a
35459 @code{guix-build-coordinator-agent-configuration} object.
35462 @deftp {Data Type} guix-build-coordinator-agent-configuration
35463 Data type representing the configuration a Guix Build Coordinator agent.
35466 @item @code{package} (default: @code{guix-build-coordinator/agent-only})
35467 The Guix Build Coordinator package to use.
35469 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
35470 The system user to run the service as.
35472 @item @code{coordinator} (default: @code{"http://localhost:8745"})
35473 The URI to use when connecting to the coordinator.
35475 @item @code{authentication}
35476 Record describing how this agent should authenticate with the
35477 coordinator. Possible record types are described below.
35479 @item @code{systems} (default: @code{#f})
35480 The systems for which this agent should fetch builds. The agent process
35481 will use the current system it's running on as the default.
35483 @item @code{max-parallel-builds} (default: @code{1})
35484 The number of builds to perform in parallel.
35486 @item @code{max-1min-load-average} (default: @code{#f})
35487 Load average value to look at when considering starting new builds, if
35488 the 1 minute load average exceeds this value, the agent will wait before
35489 starting new builds.
35491 This will be unspecified if the value is @code{#f}, and the agent will
35492 use the number of cores reported by the system as the max 1 minute load
35495 @item @code{derivation-substitute-urls} (default: @code{#f})
35496 URLs from which to attempt to fetch substitutes for derivations, if the
35497 derivations aren't already available.
35499 @item @code{non-derivation-substitute-urls} (default: @code{#f})
35500 URLs from which to attempt to fetch substitutes for build inputs, if the
35501 input store items aren't already available.
35506 @deftp {Data Type} guix-build-coordinator-agent-password-auth
35507 Data type representing an agent authenticating with a coordinator via a
35512 The UUID of the agent. This should be generated by the coordinator
35513 process, stored in the coordinator database, and used by the intended
35516 @item @code{password}
35517 The password to use when connecting to the coordinator.
35522 @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
35523 Data type representing an agent authenticating with a coordinator via a
35524 UUID and password read from a file.
35528 The UUID of the agent. This should be generated by the coordinator
35529 process, stored in the coordinator database, and used by the intended
35532 @item @code{password-file}
35533 A file containing the password to use when connecting to the
35539 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
35540 Data type representing an agent authenticating with a coordinator via a
35541 dynamic auth token and agent name.
35544 @item @code{agent-name}
35545 Name of an agent, this is used to match up to an existing entry in the
35546 database if there is one. When no existing entry is found, a new entry
35547 is automatically added.
35550 Dynamic auth token, this is created and stored in the coordinator
35551 database, and is used by the agent to authenticate.
35556 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
35557 Data type representing an agent authenticating with a coordinator via a
35558 dynamic auth token read from a file and agent name.
35561 @item @code{agent-name}
35562 Name of an agent, this is used to match up to an existing entry in the
35563 database if there is one. When no existing entry is found, a new entry
35564 is automatically added.
35566 @item @code{token-file}
35567 File containing the dynamic auth token, this is created and stored in
35568 the coordinator database, and is used by the agent to authenticate.
35573 The Guix Build Coordinator package contains a script to query an
35574 instance of the Guix Data Service for derivations to build, and then
35575 submit builds for those derivations to the coordinator. The service
35576 type below assists in running this script. This is an additional tool
35577 that may be useful when building derivations contained within an
35578 instance of the Guix Data Service.
35580 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
35581 Service type for the
35582 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
35583 value must be a @code{guix-build-coordinator-queue-builds-configuration}
35587 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
35588 Data type representing the options to the queue builds from guix data
35592 @item @code{package} (default: @code{guix-build-coordinator})
35593 The Guix Build Coordinator package to use.
35595 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
35596 The system user to run the service as.
35598 @item @code{coordinator} (default: @code{"http://localhost:8746"})
35599 The URI to use when connecting to the coordinator.
35601 @item @code{systems} (default: @code{#f})
35602 The systems for which to fetch derivations to build.
35604 @item @code{systems-and-targets} (default: @code{#f})
35605 An association list of system and target pairs for which to fetch
35606 derivations to build.
35608 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
35609 The Guix Data Service instance from which to query to find out about
35610 derivations to build.
35612 @item @code{guix-data-service-build-server-id} (default: @code{#f})
35613 The Guix Data Service build server ID corresponding to the builds being
35614 submitted. Providing this speeds up the submitting of builds as
35615 derivations that have already been submitted can be skipped before
35616 asking the coordinator to build them.
35618 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
35619 A file to record which commits have been processed, to avoid needlessly
35620 processing them again if the service is restarted.
35625 @subsubheading Guix Data Service
35626 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
35627 and provides data about GNU Guix. This includes information about
35628 packages, derivations and lint warnings.
35630 The data is stored in a PostgreSQL database, and available through a web
35633 @defvar {Scheme Variable} guix-data-service-type
35634 Service type for the Guix Data Service. Its value must be a
35635 @code{guix-data-service-configuration} object. The service optionally
35636 extends the getmail service, as the guix-commits mailing list is used to
35637 find out about changes in the Guix git repository.
35640 @deftp {Data Type} guix-data-service-configuration
35641 Data type representing the configuration of the Guix Data Service.
35644 @item @code{package} (default: @code{guix-data-service})
35645 The Guix Data Service package to use.
35647 @item @code{user} (default: @code{"guix-data-service"})
35648 The system user to run the service as.
35650 @item @code{group} (default: @code{"guix-data-service"})
35651 The system group to run the service as.
35653 @item @code{port} (default: @code{8765})
35654 The port to bind the web service to.
35656 @item @code{host} (default: @code{"127.0.0.1"})
35657 The host to bind the web service to.
35659 @item @code{getmail-idle-mailboxes} (default: @code{#f})
35660 If set, this is the list of mailboxes that the getmail service will be
35661 configured to listen to.
35663 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
35664 If set, this is the @code{getmail-retriever-configuration} object with
35665 which to configure getmail to fetch mail from the guix-commits mailing
35668 @item @code{extra-options} (default: @var{'()})
35669 Extra command line options for @code{guix-data-service}.
35671 @item @code{extra-process-jobs-options} (default: @var{'()})
35672 Extra command line options for @code{guix-data-service-process-jobs}.
35677 @subsubheading Nar Herder
35678 The @uref{https://git.cbaines.net/guix/nar-herder/about/,Nar Herder} is
35679 a utility for managing a collection of nars.
35681 @defvar {Scheme Variable} nar-herder-type
35682 Service type for the Guix Data Service. Its value must be a
35683 @code{nar-herder-configuration} object. The service optionally
35684 extends the getmail service, as the guix-commits mailing list is used to
35685 find out about changes in the Guix git repository.
35688 @deftp {Data Type} nar-herder-configuration
35689 Data type representing the configuration of the Guix Data Service.
35692 @item @code{package} (default: @code{nar-herder})
35693 The Nar Herder package to use.
35695 @item @code{user} (default: @code{"nar-herder"})
35696 The system user to run the service as.
35698 @item @code{group} (default: @code{"nar-herder"})
35699 The system group to run the service as.
35701 @item @code{port} (default: @code{8734})
35702 The port to bind the server to.
35704 @item @code{host} (default: @code{"127.0.0.1"})
35705 The host to bind the server to.
35707 @item @code{mirror} (default: @code{#f})
35708 Optional URL of the other Nar Herder instance which should be mirrored.
35709 This means that this Nar Herder instance will download it's database,
35710 and keep it up to date.
35712 @item @code{database} (default: @code{"/var/lib/nar-herder/nar_herder.db"})
35713 Location for the database. If this Nar Herder instance is mirroring
35714 another, the database will be downloaded if it doesn't exist. If this
35715 Nar Herder instance isn't mirroring another, an empty database will be
35718 @item @code{database-dump} (default: @code{"/var/lib/nar-herder/nar_herder_dump.db"})
35719 Location of the database dump. This is created and regularly updated by
35720 taking a copy of the database. This is the version of the database that
35721 is available to download.
35723 @item @code{storage} (default: @code{#f})
35724 Optional location in which to store nars.
35726 @item @code{storage-limit} (default: @code{"none"})
35727 Limit in bytes for the nars stored in the storage location. This can
35728 also be set to ``none'' so that there is no limit.
35730 When the storage location exceeds this size, nars are removed according
35731 to the nar removal criteria.
35733 @item @code{storage-nar-removal-criteria} (default: @code{'()})
35734 Criteria used to remove nars from the storage location. These are used
35735 in conjunction with the storage limit.
35737 When the storage location exceeds the storage limit size, nars will be
35738 checked against the nar removal criteria and if any of the criteria
35739 match, they will be removed. This will continue until the storage
35740 location is below the storage limit size.
35742 Each criteria is specified by a string, then an equals sign, then
35743 another string. Currently, only one criteria is supported, checking if a
35744 nar is stored on another Nar Herder instance.
35746 @item @code{ttl} (default: @code{#f})
35747 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
35748 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
35749 days, @code{1m} means 1 month, and so on.
35751 This allows the user's Guix to keep substitute information in cache for
35754 @item @code{negative-ttl} (default: @code{#f})
35755 Similarly produce @code{Cache-Control} HTTP headers to advertise the
35756 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
35757 which the HTTP 404 code is returned. By default, no negative TTL is
35760 @item @code{log-level} (default: @code{'DEBUG})
35761 Log level to use, specify a log level like @code{'INFO} to stop logging
35762 individual requests.
35767 @node Linux Services
35768 @subsection Linux Services
35771 @cindex out of memory killer
35773 @cindex early out of memory daemon
35774 @subsubheading Early OOM Service
35776 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
35777 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
35778 space and provides a more responsive and configurable alternative to the
35779 in-kernel OOM killer. It is useful to prevent the system from becoming
35780 unresponsive when it runs out of memory.
35782 @deffn {Scheme Variable} earlyoom-service-type
35783 The service type for running @command{earlyoom}, the Early OOM daemon.
35784 Its value must be a @code{earlyoom-configuration} object, described
35785 below. The service can be instantiated in its default configuration
35789 (service earlyoom-service-type)
35793 @deftp {Data Type} earlyoom-configuration
35794 This is the configuration record for the @code{earlyoom-service-type}.
35797 @item @code{earlyoom} (default: @var{earlyoom})
35798 The Earlyoom package to use.
35800 @item @code{minimum-available-memory} (default: @code{10})
35801 The threshold for the minimum @emph{available} memory, in percentages.
35803 @item @code{minimum-free-swap} (default: @code{10})
35804 The threshold for the minimum free swap memory, in percentages.
35806 @item @code{prefer-regexp} (default: @code{#f})
35807 A regular expression (as a string) to match the names of the processes
35808 that should be preferably killed.
35810 @item @code{avoid-regexp} (default: @code{#f})
35811 A regular expression (as a string) to match the names of the processes
35812 that should @emph{not} be killed.
35814 @item @code{memory-report-interval} (default: @code{0})
35815 The interval in seconds at which a memory report is printed. It is
35816 disabled by default.
35818 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
35819 A boolean indicating whether the positive adjustments set in
35820 @file{/proc/*/oom_score_adj} should be ignored.
35822 @item @code{show-debug-messages?} (default: @code{#f})
35823 A boolean indicating whether debug messages should be printed. The logs
35824 are saved at @file{/var/log/earlyoom.log}.
35826 @item @code{send-notification-command} (default: @code{#f})
35827 This can be used to provide a custom command used for sending
35833 @cindex kernel module loader
35834 @subsubheading Kernel Module Loader Service
35836 The kernel module loader service allows one to load loadable kernel
35837 modules at boot. This is especially useful for modules that don't
35838 autoload and need to be manually loaded, as is the case with
35841 @deffn {Scheme Variable} kernel-module-loader-service-type
35842 The service type for loading loadable kernel modules at boot with
35843 @command{modprobe}. Its value must be a list of strings representing
35844 module names. For example loading the drivers provided by
35845 @code{ddcci-driver-linux}, in debugging mode by passing some module
35846 parameters, can be done as follow:
35849 (use-modules (gnu) (gnu services))
35850 (use-package-modules linux)
35851 (use-service-modules linux)
35853 (define ddcci-config
35854 (plain-file "ddcci.conf"
35855 "options ddcci dyndbg delay=120"))
35859 (services (cons* (service kernel-module-loader-service-type
35860 '("ddcci" "ddcci_backlight"))
35861 (simple-service 'ddcci-config etc-service-type
35862 (list `("modprobe.d/ddcci.conf"
35865 (kernel-loadable-modules (list ddcci-driver-linux)))
35870 @cindex Platform Reliability, Availability and Serviceability daemon
35871 @subsubheading Rasdaemon Service
35873 The Rasdaemon service provides a daemon which monitors platform
35874 @acronym{RAS, Reliability@comma{} Availability@comma{} and Serviceability} reports from
35875 Linux kernel trace events, logging them to syslogd.
35877 Reliability, Availability and Serviceability is a concept used on servers meant
35878 to measure their robustness.
35880 @strong{Relability} is the probability that a system will produce correct
35884 @item Generally measured as Mean Time Between Failures (MTBF), and
35885 @item Enhanced by features that help to avoid, detect and repair hardware
35889 @strong{Availability} is the probability that a system is operational at a
35893 @item Generally measured as a percentage of downtime per a period of time, and
35894 @item Often uses mechanisms to detect and correct hardware faults in runtime.
35897 @strong{Serviceability} is the simplicity and speed with which a system can be
35898 repaired or maintained:
35901 @item Generally measured on Mean Time Between Repair (MTBR).
35905 Among the monitoring measures, the most usual ones include:
35908 @item CPU – detect errors at instruction execution and at L1/L2/L3 caches;
35909 @item Memory – add error correction logic (ECC) to detect and correct errors;
35910 @item I/O – add CRC checksums for transferred data;
35911 @item Storage – RAID, journal file systems, checksums, Self-Monitoring,
35912 Analysis and Reporting Technology (SMART).
35915 By monitoring the number of occurrences of error detections, it is possible to
35916 identify if the probability of hardware errors is increasing, and, on such
35917 case, do a preventive maintenance to replace a degraded component while those
35918 errors are correctable.
35920 For detailed information about the types of error events gathered and how to
35921 make sense of them, see the kernel administrator's guide at
35922 @url{https://www.kernel.org/doc/html/latest/admin-guide/ras.html}.
35924 @defvr {Scheme Variable} rasdaemon-service-type
35925 Service type for the @command{rasdaemon} service. It accepts a
35926 @code{rasdaemon-configuration} object. Instantiating like
35929 (service rasdaemon-service-type)
35932 will load with a default configuration, which monitors all events and logs to
35936 @deftp {Data Type} rasdaemon-configuration
35937 The data type representing the configuration of @command{rasdaemon}.
35940 @item @code{record?} (default: @code{#f})
35942 A boolean indicating whether to record the events in an SQLite database. This
35943 provides a more structured access to the information contained in the log file.
35944 The database location is hard-coded to @file{/var/lib/rasdaemon/ras-mc_event.db}.
35950 @cindex compressed swap
35951 @cindex Compressed RAM-based block devices
35952 @subsubheading Zram Device Service
35954 The Zram device service provides a compressed swap device in system
35955 memory. The Linux Kernel documentation has more information about
35956 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
35959 @deffn {Scheme Variable} zram-device-service-type
35960 This service creates the zram block device, formats it as swap and
35961 enables it as a swap device. The service's value is a
35962 @code{zram-device-configuration} record.
35964 @deftp {Data Type} zram-device-configuration
35965 This is the data type representing the configuration for the zram-device
35969 @item @code{size} (default @code{"1G"})
35970 This is the amount of space you wish to provide for the zram device. It
35971 accepts a string and can be a number of bytes or use a suffix, eg.:
35972 @code{"512M"} or @code{1024000}.
35973 @item @code{compression-algorithm} (default @code{'lzo})
35974 This is the compression algorithm you wish to use. It is difficult to
35975 list all the possible compression options, but common ones supported by
35976 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
35977 @item @code{memory-limit} (default @code{0})
35978 This is the maximum amount of memory which the zram device can use.
35979 Setting it to '0' disables the limit. While it is generally expected
35980 that compression will be 2:1, it is possible that uncompressable data
35981 can be written to swap and this is a method to limit how much memory can
35982 be used. It accepts a string and can be a number of bytes or use a
35983 suffix, eg.: @code{"2G"}.
35984 @item @code{priority} (default @code{#f})
35985 This is the priority of the swap device created from the zram device.
35986 @xref{Swap Space} for a description of swap priorities. You might want
35987 to set a specific priority for the zram device, otherwise it could end
35988 up not being used much for the reasons described there.
35994 @node Hurd Services
35995 @subsection Hurd Services
35997 @defvr {Scheme Variable} hurd-console-service-type
35998 This service starts the fancy @code{VGA} console client on the Hurd.
36000 The service's value is a @code{hurd-console-configuration} record.
36003 @deftp {Data Type} hurd-console-configuration
36004 This is the data type representing the configuration for the
36005 hurd-console-service.
36008 @item @code{hurd} (default: @var{hurd})
36009 The Hurd package to use.
36013 @defvr {Scheme Variable} hurd-getty-service-type
36014 This service starts a tty using the Hurd @code{getty} program.
36016 The service's value is a @code{hurd-getty-configuration} record.
36019 @deftp {Data Type} hurd-getty-configuration
36020 This is the data type representing the configuration for the
36021 hurd-getty-service.
36024 @item @code{hurd} (default: @var{hurd})
36025 The Hurd package to use.
36028 The name of the console this Getty runs on---e.g., @code{"tty1"}.
36030 @item @code{baud-rate} (default: @code{38400})
36031 An integer specifying the baud rate of the tty.
36036 @node Miscellaneous Services
36037 @subsection Miscellaneous Services
36039 @cindex fingerprint
36040 @subsubheading Fingerprint Service
36042 The @code{(gnu services authentication)} module provides a DBus service to
36043 read and identify fingerprints via a fingerprint sensor.
36045 @defvr {Scheme Variable} fprintd-service-type
36046 The service type for @command{fprintd}, which provides the fingerprint
36047 reading capability.
36050 (service fprintd-service-type)
36055 @subsubheading System Control Service
36057 The @code{(gnu services sysctl)} provides a service to configure kernel
36058 parameters at boot.
36060 @defvr {Scheme Variable} sysctl-service-type
36061 The service type for @command{sysctl}, which modifies kernel parameters
36062 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
36066 (service sysctl-service-type
36067 (sysctl-configuration
36068 (settings '(("net.ipv4.ip_forward" . "1")))))
36071 Since @code{sysctl-service-type} is used in the default lists of
36072 services, @code{%base-services} and @code{%desktop-services}, you can
36073 use @code{modify-services} to change its configuration and add the
36074 kernel parameters that you want (@pxref{Service Reference,
36075 @code{modify-services}}).
36078 (modify-services %base-services
36079 (sysctl-service-type config =>
36080 (sysctl-configuration
36081 (settings (append '(("net.ipv4.ip_forward" . "1"))
36082 %default-sysctl-settings)))))
36087 @deftp {Data Type} sysctl-configuration
36088 The data type representing the configuration of @command{sysctl}.
36091 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
36092 The @command{sysctl} executable to use.
36094 @item @code{settings} (default: @code{%default-sysctl-settings})
36095 An association list specifies kernel parameters and their values.
36099 @defvr {Scheme Variable} %default-sysctl-settings
36100 An association list specifying the default @command{sysctl} parameters
36105 @subsubheading PC/SC Smart Card Daemon Service
36107 The @code{(gnu services security-token)} module provides the following service
36108 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
36109 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
36110 manager that coordinates communications with smart card readers, smart cards
36111 and cryptographic tokens that are connected to the system.
36113 @defvr {Scheme Variable} pcscd-service-type
36114 Service type for the @command{pcscd} service. Its value must be a
36115 @code{pcscd-configuration} object. To run pcscd in the default
36116 configuration, instantiate it as:
36119 (service pcscd-service-type)
36123 @deftp {Data Type} pcscd-configuration
36124 The data type representing the configuration of @command{pcscd}.
36127 @item @code{pcsc-lite} (default: @code{pcsc-lite})
36128 The pcsc-lite package that provides pcscd.
36129 @item @code{usb-drivers} (default: @code{(list ccid)})
36130 List of packages that provide USB drivers to pcscd. Drivers are expected to be
36131 under @file{pcsc/drivers} in the store directory of the package.
36136 @subsubheading Lirc Service
36138 The @code{(gnu services lirc)} module provides the following service.
36140 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
36141 [#:device #f] [#:driver #f] [#:config-file #f] @
36142 [#:extra-options '()]
36143 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
36144 decodes infrared signals from remote controls.
36146 Optionally, @var{device}, @var{driver} and @var{config-file}
36147 (configuration file name) may be specified. See @command{lircd} manual
36150 Finally, @var{extra-options} is a list of additional command-line options
36151 passed to @command{lircd}.
36155 @subsubheading Spice Service
36157 The @code{(gnu services spice)} module provides the following service.
36159 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
36160 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
36161 that enables sharing the clipboard with a vm and setting the guest display
36162 resolution when the graphical console window resizes.
36165 @cindex inputattach
36166 @subsubheading inputattach Service
36168 @cindex tablet input, for Xorg
36169 @cindex touchscreen input, for Xorg
36170 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
36171 use input devices such as Wacom tablets, touchscreens, or joysticks with the
36172 Xorg display server.
36174 @deffn {Scheme Variable} inputattach-service-type
36175 Type of a service that runs @command{inputattach} on a device and
36176 dispatches events from it.
36179 @deftp {Data Type} inputattach-configuration
36181 @item @code{device-type} (default: @code{"wacom"})
36182 The type of device to connect to. Run @command{inputattach --help}, from the
36183 @code{inputattach} package, to see the list of supported device types.
36185 @item @code{device} (default: @code{"/dev/ttyS0"})
36186 The device file to connect to the device.
36188 @item @code{baud-rate} (default: @code{#f})
36189 Baud rate to use for the serial connection.
36190 Should be a number or @code{#f}.
36192 @item @code{log-file} (default: @code{#f})
36193 If true, this must be the name of a file to log messages to.
36197 @subsubheading Dictionary Service
36199 The @code{(gnu services dict)} module provides the following service:
36201 @defvr {Scheme Variable} dicod-service-type
36202 This is the type of the service that runs the @command{dicod} daemon, an
36203 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
36206 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
36207 Return a service that runs the @command{dicod} daemon, an implementation
36208 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
36210 The optional @var{config} argument specifies the configuration for
36211 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
36212 default it serves the GNU Collaborative International Dictionary of English.
36214 You can add @command{open localhost} to your @file{~/.dico} file to make
36215 @code{localhost} the default server for @command{dico} client
36216 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
36219 @deftp {Data Type} dicod-configuration
36220 Data type representing the configuration of dicod.
36223 @item @code{dico} (default: @var{dico})
36224 Package object of the GNU Dico dictionary server.
36226 @item @code{interfaces} (default: @var{'("localhost")})
36227 This is the list of IP addresses and ports and possibly socket file
36228 names to listen to (@pxref{Server Settings, @code{listen} directive,,
36229 dico, GNU Dico Manual}).
36231 @item @code{handlers} (default: @var{'()})
36232 List of @code{<dicod-handler>} objects denoting handlers (module instances).
36234 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
36235 List of @code{<dicod-database>} objects denoting dictionaries to be served.
36239 @deftp {Data Type} dicod-handler
36240 Data type representing a dictionary handler (module instance).
36244 Name of the handler (module instance).
36246 @item @code{module} (default: @var{#f})
36247 Name of the dicod module of the handler (instance). If it is @code{#f},
36248 the module has the same name as the handler.
36249 (@pxref{Modules,,, dico, GNU Dico Manual}).
36251 @item @code{options}
36252 List of strings or gexps representing the arguments for the module handler
36256 @deftp {Data Type} dicod-database
36257 Data type representing a dictionary database.
36261 Name of the database, will be used in DICT commands.
36263 @item @code{handler}
36264 Name of the dicod handler (module instance) used by this database
36265 (@pxref{Handlers,,, dico, GNU Dico Manual}).
36267 @item @code{complex?} (default: @var{#f})
36268 Whether the database configuration complex. The complex configuration
36269 will need a corresponding @code{<dicod-handler>} object, otherwise not.
36271 @item @code{options}
36272 List of strings or gexps representing the arguments for the database
36273 (@pxref{Databases,,, dico, GNU Dico Manual}).
36277 @defvr {Scheme Variable} %dicod-database:gcide
36278 A @code{<dicod-database>} object serving the GNU Collaborative International
36279 Dictionary of English using the @code{gcide} package.
36282 The following is an example @code{dicod-service} configuration.
36285 (dicod-service #:config
36286 (dicod-configuration
36287 (handlers (list (dicod-handler
36291 (list #~(string-append "dbdir=" #$wordnet))))))
36292 (databases (list (dicod-database
36295 (handler "wordnet")
36296 (options '("database=wn")))
36297 %dicod-database:gcide))))
36301 @subsubheading Docker Service
36303 The @code{(gnu services docker)} module provides the following services.
36305 @defvr {Scheme Variable} docker-service-type
36307 This is the type of the service that runs @url{https://www.docker.com,Docker},
36308 a daemon that can execute application bundles (sometimes referred to as
36309 ``containers'') in isolated environments.
36313 @deftp {Data Type} docker-configuration
36314 This is the data type representing the configuration of Docker and Containerd.
36318 @item @code{docker} (default: @code{docker})
36319 The Docker daemon package to use.
36321 @item @code{docker-cli} (default: @code{docker-cli})
36322 The Docker client package to use.
36324 @item @code{containerd} (default: @var{containerd})
36325 The Containerd package to use.
36327 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
36328 The Docker user-land networking proxy package to use.
36330 @item @code{enable-proxy?} (default @code{#t})
36331 Enable or disable the use of the Docker user-land networking proxy.
36333 @item @code{debug?} (default @code{#f})
36334 Enable or disable debug output.
36336 @item @code{enable-iptables?} (default @code{#t})
36337 Enable or disable the addition of iptables rules.
36339 @item @code{environment-variables} (default: @code{()})
36340 List of environment variables to set for @command{dockerd}.
36342 This must be a list of strings where each string has the form
36343 @samp{@var{key}=@var{value}} as in this example:
36346 (list "LANGUAGE=eo:ca:eu"
36347 "TMPDIR=/tmp/dockerd")
36353 @cindex Singularity, container service
36354 @defvr {Scheme Variable} singularity-service-type
36355 This is the type of the service that allows you to run
36356 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
36357 create and run application bundles (aka. ``containers''). The value for this
36358 service is the Singularity package to use.
36360 The service does not install a daemon; instead, it installs helper programs as
36361 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
36362 @command{singularity run} and similar commands.
36366 @subsubheading Auditd Service
36368 The @code{(gnu services auditd)} module provides the following service.
36370 @defvr {Scheme Variable} auditd-service-type
36372 This is the type of the service that runs
36373 @url{https://people.redhat.com/sgrubb/audit/,auditd},
36374 a daemon that tracks security-relevant information on your system.
36376 Examples of things that can be tracked:
36386 Failed login attempts
36393 @command{auditctl} from the @code{audit} package can be used in order
36394 to add or remove events to be tracked (until the next reboot).
36395 In order to permanently track events, put the command line arguments
36396 of auditctl into a file called @code{audit.rules} in the configuration
36397 directory (see below).
36398 @command{aureport} from the @code{audit} package can be used in order
36399 to view a report of all recorded events.
36400 The audit daemon by default logs into the file
36401 @file{/var/log/audit.log}.
36405 @deftp {Data Type} auditd-configuration
36406 This is the data type representing the configuration of auditd.
36410 @item @code{audit} (default: @code{audit})
36411 The audit package to use.
36413 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
36414 The directory containing the configuration file for the audit package, which
36415 must be named @code{auditd.conf}, and optionally some audit rules to
36416 instantiate on startup.
36422 @subsubheading R-Shiny service
36424 The @code{(gnu services science)} module provides the following service.
36426 @defvr {Scheme Variable} rshiny-service-type
36428 This is a type of service which is used to run a webapp created with
36429 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
36430 variable and runs the provided script to call @code{runApp}.
36432 @deftp {Data Type} rshiny-configuration
36433 This is the data type representing the configuration of rshiny.
36437 @item @code{package} (default: @code{r-shiny})
36438 The package to use.
36440 @item @code{binary} (default @code{"rshiny"})
36441 The name of the binary or shell script located at @code{package/bin/} to
36442 run when the service is run.
36444 The common way to create this file is as follows:
36448 (let* ((out (assoc-ref %outputs "out"))
36449 (targetdir (string-append out "/share/" ,name))
36450 (app (string-append out "/bin/" ,name))
36451 (Rbin (search-input-file %build-inputs "/bin/Rscript")))
36453 (mkdir-p (string-append out "/bin"))
36454 (call-with-output-file app
36460 runApp(launch.browser=0, port=4202)~%\n"
36469 @subsubheading Nix service
36471 The @code{(gnu services nix)} module provides the following service.
36473 @defvr {Scheme Variable} nix-service-type
36475 This is the type of the service that runs build daemon of the
36476 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
36480 (use-modules (gnu))
36481 (use-service-modules nix)
36482 (use-package-modules package-management)
36486 (packages (append (list nix)
36489 (services (append (list (service nix-service-type))
36493 After @command{guix system reconfigure} configure Nix for your user:
36496 @item Add a Nix channel and update it. See
36497 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
36499 @item Create a symlink to your profile and activate Nix profile:
36503 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
36504 $ source /run/current-system/profile/etc/profile.d/nix.sh
36509 @deftp {Data Type} nix-configuration
36510 This data type represents the configuration of the Nix daemon.
36513 @item @code{nix} (default: @code{nix})
36514 The Nix package to use.
36516 @item @code{sandbox} (default: @code{#t})
36517 Specifies whether builds are sandboxed by default.
36519 @item @code{build-sandbox-items} (default: @code{'()})
36520 This is a list of strings or objects appended to the
36521 @code{build-sandbox-items} field of the configuration file.
36523 @item @code{extra-config} (default: @code{'()})
36524 This is a list of strings or objects appended to the configuration file.
36525 It is used to pass extra text to be added verbatim to the configuration
36528 @item @code{extra-options} (default: @code{'()})
36529 Extra command line options for @code{nix-service-type}.
36534 @subsubheading Fail2Ban service
36536 @uref{http://www.fail2ban.org/, @code{fail2ban}} scans log files
36537 (e.g. @code{/var/log/apache/error_log}) and bans IP addresses that show
36538 malicious signs -- repeated password failures, attempts to make use of
36541 @code{fail2ban-service-type} service type is provided by the @code{(gnu
36542 services security)} module.
36544 This service type runs the @code{fail2ban} daemon. It can be configured
36545 in various ways, which are:
36548 @item Basic configuration
36549 The basic parameters of the Fail2Ban service can be configured via its
36550 @code{fail2ban} configuration, which is documented below.
36552 @item User-specified jail extensions
36553 The @code{fail2ban-jail-service} function can be used to add new
36556 @item Shepherd extension mechanism
36557 Service developers can extend the @code{fail2ban-service-type} service
36558 type itself via the usual service extension mechanism.
36561 @defvr {Scheme Variable} fail2ban-service-type
36563 This is the type of the service that runs @code{fail2ban} daemon. Below
36564 is an example of a basic, explicit configuration:
36569 (service fail2ban-service-type
36570 (fail2ban-configuration
36573 (fail2ban-jail-configuration
36576 ;; There is no implicit dependency on an actual SSH
36577 ;; service, so you need to provide one.
36578 (service openssh-service-type))
36583 @deffn {Scheme Procedure} fail2ban-jail-service @var{svc-type} @var{jail}
36584 Extend @var{svc-type}, a @code{<service-type>} object with @var{jail}, a
36585 @code{fail2ban-jail-configuration} object.
36593 ;; The 'fail2ban-jail-service' procedure can extend any service type
36594 ;; with a fail2ban jail. This removes the requirement to explicitly
36595 ;; extend services with fail2ban-service-type.
36596 (fail2ban-jail-service
36597 openssh-service-type
36598 (fail2ban-jail-configuration
36601 (openssh-configuration ...))))
36605 Below is the reference for the different @code{jail-service-type}
36606 configuration records.
36608 @c The documentation is to be auto-generated via
36609 @c 'generate-documentation'. See at the bottom of (gnu services
36612 @deftp {Data Type} fail2ban-configuration
36613 Available @code{fail2ban-configuration} fields are:
36616 @item @code{fail2ban} (default: @code{fail2ban}) (type: package)
36617 The @code{fail2ban} package to use. It is used for both binaries and as
36618 base default configuration that is to be extended with
36619 @code{<fail2ban-jail-configuration>} objects.
36621 @item @code{run-directory} (default: @code{"/var/run/fail2ban"}) (type: string)
36622 The state directory for the @code{fail2ban} daemon.
36624 @item @code{jails} (default: @code{()}) (type: list-of-fail2ban-jail-configurations)
36625 Instances of @code{<fail2ban-jail-configuration>} collected from
36628 @item @code{extra-jails} (default: @code{()}) (type: list-of-fail2ban-jail-configurations)
36629 Instances of @code{<fail2ban-jail-configuration>} explicitly provided.
36631 @item @code{extra-content} (default: @code{()}) (type: text-config)
36632 Extra raw content to add to the end of the @file{jail.local} file,
36633 provided as a list of file-like objects.
36639 @deftp {Data Type} fail2ban-ignore-cache-configuration
36640 Available @code{fail2ban-ignore-cache-configuration} fields are:
36643 @item @code{key} (type: string)
36646 @item @code{max-count} (type: integer)
36649 @item @code{max-time} (type: integer)
36656 @deftp {Data Type} fail2ban-jail-action-configuration
36657 Available @code{fail2ban-jail-action-configuration} fields are:
36660 @item @code{name} (type: string)
36663 @item @code{arguments} (default: @code{()}) (type: list-of-arguments)
36670 @deftp {Data Type} fail2ban-jail-configuration
36671 Available @code{fail2ban-jail-configuration} fields are:
36674 @item @code{name} (type: string)
36675 Required name of this jail configuration.
36677 @item @code{enabled?} (default: @code{#t}) (type: boolean)
36678 Whether this jail is enabled.
36680 @item @code{backend} (type: maybe-symbol)
36681 Backend to use to detect changes in the @code{log-path}. The default is
36682 'auto. To consult the defaults of the jail configuration, refer to the
36683 @file{/etc/fail2ban/jail.conf} file of the @code{fail2ban} package.
36685 @item @code{max-retry} (type: maybe-integer)
36686 The number of failures before a host get banned (e.g. @code{(max-retry
36689 @item @code{max-matches} (type: maybe-integer)
36690 The number of matches stored in ticket (resolvable via tag
36691 @code{<matches>}) in action.
36693 @item @code{find-time} (type: maybe-string)
36694 The time window during which the maximum retry count must be reached for
36695 an IP address to be banned. A host is banned if it has generated
36696 @code{max-retry} during the last @code{find-time} seconds (e.g.
36697 @code{(find-time "10m")}). It can be provided in seconds or using
36698 Fail2Ban's "time abbreviation format", as described in @command{man 5
36701 @item @code{ban-time} (type: maybe-string)
36702 The duration, in seconds or time abbreviated format, that a ban should
36703 last. (e.g. @code{(ban-time "10m")}).
36705 @item @code{ban-time-increment?} (type: maybe-boolean)
36706 Whether to consider past bans to compute increases to the default ban
36707 time of a specific IP address.
36709 @item @code{ban-time-factor} (type: maybe-string)
36710 The coefficient to use to compute an exponentially growing ban time.
36712 @item @code{ban-time-formula} (type: maybe-string)
36713 This is the formula used to calculate the next value of a ban time.
36715 @item @code{ban-time-multipliers} (type: maybe-string)
36716 Used to calculate next value of ban time instead of formula.
36718 @item @code{ban-time-max-time} (type: maybe-string)
36719 The maximum number of seconds a ban should last.
36721 @item @code{ban-time-rnd-time} (type: maybe-string)
36722 The maximum number of seconds a randomized ban time should last. This
36723 can be useful to stop ``clever'' botnets calculating the exact time an
36724 IP address can be unbanned again.
36726 @item @code{ban-time-overall-jails?} (type: maybe-boolean)
36727 When true, it specifies the search of an IP address in the database
36728 should be made across all jails. Otherwise, only the current jail of
36729 the ban IP address is considered.
36731 @item @code{ignore-self?} (type: maybe-boolean)
36732 Never ban the local machine's own IP address.
36734 @item @code{ignore-ip} (default: @code{()}) (type: list-of-strings)
36735 A list of IP addresses, CIDR masks or DNS hosts to ignore.
36736 @code{fail2ban} will not ban a host which matches an address in this
36739 @item @code{ignore-cache} (type: maybe-fail2ban-ignore-cache-configuration)
36740 Provide cache parameters for the ignore failure check.
36742 @item @code{filter} (type: maybe-fail2ban-jail-filter-configuration)
36743 The filter to use by the jail, specified via a
36744 @code{<fail2ban-jail-filter-configuration>} object. By default, jails
36745 have names matching their filter name.
36747 @item @code{log-time-zone} (type: maybe-string)
36748 The default time zone for log lines that do not have one.
36750 @item @code{log-encoding} (type: maybe-symbol)
36751 The encoding of the log files handled by the jail. Possible values are:
36752 @code{'ascii}, @code{'utf-8} and @code{'auto}.
36754 @item @code{log-path} (default: @code{()}) (type: list-of-strings)
36755 The file names of the log files to be monitored.
36757 @item @code{action} (default: @code{()}) (type: list-of-fail2ban-jail-actions)
36758 A list of @code{<fail2ban-jail-action-configuration>}.
36760 @item @code{extra-content} (default: @code{()}) (type: text-config)
36761 Extra content for the jail configuration, provided as a list of file-like
36768 @deftp {Data Type} fail2ban-jail-filter-configuration
36769 Available @code{fail2ban-jail-filter-configuration} fields are:
36772 @item @code{name} (type: string)
36775 @item @code{mode} (type: maybe-string)
36782 @c End of auto-generated fail2ban documentation.
36784 @node Setuid Programs
36785 @section Setuid Programs
36787 @cindex setuid programs
36788 @cindex setgid programs
36789 Some programs need to run with elevated privileges, even when they are
36790 launched by unprivileged users. A notorious example is the
36791 @command{passwd} program, which users can run to change their
36792 password, and which needs to access the @file{/etc/passwd} and
36793 @file{/etc/shadow} files---something normally restricted to root, for
36794 obvious security reasons. To address that, @command{passwd} should be
36795 @dfn{setuid-root}, meaning that it always runs with root privileges
36796 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
36797 for more info about the setuid mechanism).
36799 The store itself @emph{cannot} contain setuid programs: that would be a
36800 security issue since any user on the system can write derivations that
36801 populate the store (@pxref{The Store}). Thus, a different mechanism is
36802 used: instead of changing the setuid or setgid bits directly on files that
36803 are in the store, we let the system administrator @emph{declare} which
36804 programs should be entrusted with these additional privileges.
36806 The @code{setuid-programs} field of an @code{operating-system}
36807 declaration contains a list of @code{<setuid-program>} denoting the
36808 names of programs to have a setuid or setgid bit set (@pxref{Using the
36809 Configuration System}). For instance, the @command{mount.nfs} program,
36810 which is part of the nfs-utils package, with a setuid root can be
36811 designated like this:
36815 (program (file-append nfs-utils "/sbin/mount.nfs")))
36818 And then, to make @command{mount.nfs} setuid on your system, add the
36819 previous example to your operating system declaration by appending it to
36820 @code{%setuid-programs} like this:
36824 ;; Some fields omitted...
36826 (append (list (setuid-program
36827 (program (file-append nfs-utils "/sbin/mount.nfs"))))
36828 %setuid-programs)))
36831 @deftp {Data Type} setuid-program
36832 This data type represents a program with a setuid or setgid bit set.
36835 @item @code{program}
36836 A file-like object having its setuid and/or setgid bit set.
36838 @item @code{setuid?} (default: @code{#t})
36839 Whether to set user setuid bit.
36841 @item @code{setgid?} (default: @code{#f})
36842 Whether to set group setgid bit.
36844 @item @code{user} (default: @code{0})
36845 UID (integer) or user name (string) for the user owner of the program,
36848 @item @code{group} (default: @code{0})
36849 GID (integer) goup name (string) for the group owner of the program,
36855 A default set of setuid programs is defined by the
36856 @code{%setuid-programs} variable of the @code{(gnu system)} module.
36858 @defvr {Scheme Variable} %setuid-programs
36859 A list of @code{<setuid-program>} denoting common programs that are
36862 The list includes commands such as @command{passwd}, @command{ping},
36863 @command{su}, and @command{sudo}.
36866 Under the hood, the actual setuid programs are created in the
36867 @file{/run/setuid-programs} directory at system activation time. The
36868 files in this directory refer to the ``real'' binaries, which are in the
36871 @node X.509 Certificates
36872 @section X.509 Certificates
36874 @cindex HTTPS, certificates
36875 @cindex X.509 certificates
36877 Web servers available over HTTPS (that is, HTTP over the transport-layer
36878 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
36879 that the client can then use to @emph{authenticate} the server. To do
36880 that, clients verify that the server's certificate is signed by a
36881 so-called @dfn{certificate authority} (CA). But to verify the CA's
36882 signature, clients must have first acquired the CA's certificate.
36884 Web browsers such as GNU@tie{}IceCat include their own set of CA
36885 certificates, such that they are able to verify CA signatures
36888 However, most other programs that can talk HTTPS---@command{wget},
36889 @command{git}, @command{w3m}, etc.---need to be told where CA
36890 certificates can be found.
36892 @cindex @code{nss-certs}
36893 In Guix, this is done by adding a package that provides certificates
36894 to the @code{packages} field of the @code{operating-system} declaration
36895 (@pxref{operating-system Reference}). Guix includes one such package,
36896 @code{nss-certs}, which is a set of CA certificates provided as part of
36897 Mozilla's Network Security Services.
36899 Note that it is @emph{not} part of @code{%base-packages}, so you need to
36900 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
36901 most applications and libraries look for certificates by default, points
36902 to the certificates installed globally.
36904 Unprivileged users, including users of Guix on a foreign distro,
36905 can also install their own certificate package in
36906 their profile. A number of environment variables need to be defined so
36907 that applications and libraries know where to find them. Namely, the
36908 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
36909 variables. Some applications add their own environment variables; for
36910 instance, the Git version control system honors the certificate bundle
36911 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
36912 would typically run something like:
36915 guix install nss-certs
36916 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
36917 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
36918 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
36921 As another example, R requires the @env{CURL_CA_BUNDLE} environment
36922 variable to point to a certificate bundle, so you would have to run
36923 something like this:
36926 guix install nss-certs
36927 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
36930 For other applications you may want to look up the required environment
36931 variable in the relevant documentation.
36934 @node Name Service Switch
36935 @section Name Service Switch
36937 @cindex name service switch
36939 The @code{(gnu system nss)} module provides bindings to the
36940 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
36941 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
36942 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
36943 extended with new ``name'' lookup methods for system databases, which
36944 includes host names, service names, user accounts, and more (@pxref{Name
36945 Service Switch, System Databases and Name Service Switch,, libc, The GNU
36946 C Library Reference Manual}).
36948 The NSS configuration specifies, for each system database, which lookup
36949 method is to be used, and how the various methods are chained
36950 together---for instance, under which circumstances NSS should try the
36951 next method in the list. The NSS configuration is given in the
36952 @code{name-service-switch} field of @code{operating-system} declarations
36953 (@pxref{operating-system Reference, @code{name-service-switch}}).
36956 @cindex .local, host name lookup
36957 As an example, the declaration below configures the NSS to use the
36958 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
36959 back-end}, which supports host name lookups over multicast DNS (mDNS)
36960 for host names ending in @code{.local}:
36963 (name-service-switch
36964 (hosts (list %files ;first, check /etc/hosts
36966 ;; If the above did not succeed, try
36967 ;; with 'mdns_minimal'.
36969 (name "mdns_minimal")
36971 ;; 'mdns_minimal' is authoritative for
36972 ;; '.local'. When it returns "not found",
36973 ;; no need to try the next methods.
36974 (reaction (lookup-specification
36975 (not-found => return))))
36977 ;; Then fall back to DNS.
36981 ;; Finally, try with the "full" 'mdns'.
36986 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
36987 contains this configuration, so you will not have to type it if all you
36988 want is to have @code{.local} host lookup working.
36990 Note that, in this case, in addition to setting the
36991 @code{name-service-switch} of the @code{operating-system} declaration,
36992 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
36993 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
36994 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
36995 to the name service cache daemon (@pxref{Base Services,
36996 @code{nscd-service}}).
36998 For convenience, the following variables provide typical NSS
37001 @defvr {Scheme Variable} %default-nss
37002 This is the default name service switch configuration, a
37003 @code{name-service-switch} object.
37006 @defvr {Scheme Variable} %mdns-host-lookup-nss
37007 This is the name service switch configuration with support for host name
37008 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
37011 The reference for name service switch configuration is given below. It
37012 is a direct mapping of the configuration file format of the C library , so
37013 please refer to the C library manual for more information (@pxref{NSS
37014 Configuration File,,, libc, The GNU C Library Reference Manual}).
37015 Compared to the configuration file format of libc NSS, it has the advantage
37016 not only of adding this warm parenthetic feel that we like, but also
37017 static checks: you will know about syntax errors and typos as soon as you
37018 run @command{guix system}.
37020 @deftp {Data Type} name-service-switch
37022 This is the data type representation the configuration of libc's name
37023 service switch (NSS). Each field below represents one of the supported
37040 The system databases handled by the NSS@. Each of these fields must be a
37041 list of @code{<name-service>} objects (see below).
37045 @deftp {Data Type} name-service
37047 This is the data type representing an actual name service and the
37048 associated lookup action.
37052 A string denoting the name service (@pxref{Services in the NSS
37053 configuration,,, libc, The GNU C Library Reference Manual}).
37055 Note that name services listed here must be visible to nscd. This is
37056 achieved by passing the @code{#:name-services} argument to
37057 @code{nscd-service} the list of packages providing the needed name
37058 services (@pxref{Base Services, @code{nscd-service}}).
37061 An action specified using the @code{lookup-specification} macro
37062 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
37063 Reference Manual}). For example:
37066 (lookup-specification (unavailable => continue)
37067 (success => return))
37072 @node Initial RAM Disk
37073 @section Initial RAM Disk
37076 @cindex initial RAM disk
37077 For bootstrapping purposes, the Linux-Libre kernel is passed an
37078 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
37079 root file system as well as an initialization script. The latter is
37080 responsible for mounting the real root file system, and for loading any
37081 kernel modules that may be needed to achieve that.
37083 The @code{initrd-modules} field of an @code{operating-system}
37084 declaration allows you to specify Linux-libre kernel modules that must
37085 be available in the initrd. In particular, this is where you would list
37086 modules needed to actually drive the hard disk where your root partition
37087 is---although the default value of @code{initrd-modules} should cover
37088 most use cases. For example, assuming you need the @code{megaraid_sas}
37089 module in addition to the default modules to be able to access your root
37090 file system, you would write:
37095 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
37098 @defvr {Scheme Variable} %base-initrd-modules
37099 This is the list of kernel modules included in the initrd by default.
37102 Furthermore, if you need lower-level customization, the @code{initrd}
37103 field of an @code{operating-system} declaration allows
37104 you to specify which initrd you would like to use. The @code{(gnu
37105 system linux-initrd)} module provides three ways to build an initrd: the
37106 high-level @code{base-initrd} procedure and the low-level
37107 @code{raw-initrd} and @code{expression->initrd} procedures.
37109 The @code{base-initrd} procedure is intended to cover most common uses.
37110 For example, if you want to add a bunch of kernel modules to be loaded
37111 at boot time, you can define the @code{initrd} field of the operating
37112 system declaration like this:
37115 (initrd (lambda (file-systems . rest)
37116 ;; Create a standard initrd but set up networking
37117 ;; with the parameters QEMU expects by default.
37118 (apply base-initrd file-systems
37119 #:qemu-networking? #t
37123 The @code{base-initrd} procedure also handles common use cases that
37124 involves using the system as a QEMU guest, or as a ``live'' system with
37125 volatile root file system.
37127 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
37128 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
37129 such as trying to guess which kernel modules and packages should be included
37130 to the initrd. An example use of @code{raw-initrd} is when a user has
37131 a custom Linux kernel configuration and default kernel modules included by
37132 @code{base-initrd} are not available.
37134 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
37135 honors several options passed on the Linux kernel command line
37136 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
37137 @code{-append} option of QEMU), notably:
37140 @item gnu.load=@var{boot}
37141 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
37142 program, once it has mounted the root file system.
37144 Guix uses this option to yield control to a boot program that runs the
37145 service activation programs and then spawns the GNU@tie{}Shepherd, the
37146 initialization system.
37148 @item root=@var{root}
37149 Mount @var{root} as the root file system. @var{root} can be a device
37150 name like @code{/dev/sda1}, a file system label, or a file system UUID.
37151 When unspecified, the device name from the root file system of the
37152 operating system declaration is used.
37154 @item rootfstype=@var{type}
37155 Set the type of the root file system. It overrides the @code{type}
37156 field of the root file system specified via the @code{operating-system}
37157 declaration, if any.
37159 @item rootflags=@var{options}
37160 Set the mount @emph{options} of the root file system. It overrides the
37161 @code{options} field of the root file system specified via the
37162 @code{operating-system} declaration, if any.
37164 @item fsck.mode=@var{mode}
37165 Whether to check the @var{root} file system for errors before mounting
37166 it. @var{mode} is one of @code{skip} (never check), @code{force} (always
37167 check), or @code{auto} to respect the root @code{<file-system>} object's
37168 @code{check?} setting (@pxref{File Systems}) and run a full scan only if
37169 the file system was not cleanly shut down.
37171 @code{auto} is the default if this option is not present or if @var{mode}
37172 is not one of the above.
37174 @item fsck.repair=@var{level}
37175 The level of repairs to perform automatically if errors are found in the
37176 @var{root} file system. @var{level} is one of @code{no} (do not write to
37177 @var{root} at all if possible), @code{yes} (repair as much as possible),
37178 or @code{preen} to repair problems considered safe to repair automatically.
37180 @code{preen} is the default if this option is not present or if @var{level}
37181 is not one of the above.
37183 @item gnu.system=@var{system}
37184 Have @file{/run/booted-system} and @file{/run/current-system} point to
37187 @item modprobe.blacklist=@var{modules}@dots{}
37188 @cindex module, black-listing
37189 @cindex black list, of kernel modules
37190 Instruct the initial RAM disk as well as the @command{modprobe} command
37191 (from the kmod package) to refuse to load @var{modules}. @var{modules}
37192 must be a comma-separated list of module names---e.g.,
37193 @code{usbkbd,9pnet}.
37196 Start a read-eval-print loop (REPL) from the initial RAM disk before it
37197 tries to load kernel modules and to mount the root file system. Our
37198 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
37199 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
37200 Manual}, for more information on Guile's REPL.
37204 Now that you know all the features that initial RAM disks produced by
37205 @code{base-initrd} and @code{raw-initrd} provide,
37206 here is how to use it and customize it further.
37209 @cindex initial RAM disk
37210 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
37211 [#:linux-modules '()] [#:mapped-devices '()] @
37212 [#:keyboard-layout #f] @
37213 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
37214 Return a derivation that builds a raw initrd. @var{file-systems} is
37215 a list of file systems to be mounted by the initrd, possibly in addition to
37216 the root file system specified on the kernel command line via @option{root}.
37217 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
37218 @var{mapped-devices} is a list of device mappings to realize before
37219 @var{file-systems} are mounted (@pxref{Mapped Devices}).
37220 @var{helper-packages} is a list of packages to be copied in the initrd.
37222 include @code{e2fsck/static} or other packages needed by the initrd to check
37223 the root file system.
37225 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
37226 the desired console keyboard layout. This is done before @var{mapped-devices}
37227 are set up and before @var{file-systems} are mounted such that, should the
37228 user need to enter a passphrase or use the REPL, this happens using the
37229 intended keyboard layout.
37231 When @var{qemu-networking?} is true, set up networking with the standard QEMU
37232 parameters. When @var{virtio?} is true, load additional modules so that the
37233 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
37235 When @var{volatile-root?} is true, the root file system is writable but any changes
37239 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
37240 [#:mapped-devices '()] [#:keyboard-layout #f] @
37241 [#:qemu-networking? #f] [#:volatile-root? #f] @
37242 [#:linux-modules '()]
37243 Return as a file-like object a generic initrd, with kernel
37244 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
37245 mounted by the initrd, possibly in addition to the root file system specified
37246 on the kernel command line via @option{root}. @var{mapped-devices} is a list of device
37247 mappings to realize before @var{file-systems} are mounted.
37249 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
37250 the desired console keyboard layout. This is done before @var{mapped-devices}
37251 are set up and before @var{file-systems} are mounted such that, should the
37252 user need to enter a passphrase or use the REPL, this happens using the
37253 intended keyboard layout.
37255 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
37257 The initrd is automatically populated with all the kernel modules necessary
37258 for @var{file-systems} and for the given options. Additional kernel
37259 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
37260 loaded at boot time in the order in which they appear.
37263 Needless to say, the initrds we produce and use embed a
37264 statically-linked Guile, and the initialization program is a Guile
37265 program. That gives a lot of flexibility. The
37266 @code{expression->initrd} procedure builds such an initrd, given the
37267 program to run in that initrd.
37269 @deffn {Scheme Procedure} expression->initrd @var{exp} @
37270 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
37271 Return as a file-like object a Linux initrd (a gzipped cpio archive)
37272 containing @var{guile} and that evaluates @var{exp}, a G-expression,
37273 upon booting. All the derivations referenced by @var{exp} are
37274 automatically copied to the initrd.
37277 @node Bootloader Configuration
37278 @section Bootloader Configuration
37281 @cindex boot loader
37283 The operating system supports multiple bootloaders. The bootloader is
37284 configured using @code{bootloader-configuration} declaration. All the
37285 fields of this structure are bootloader agnostic except for one field,
37286 @code{bootloader} that indicates the bootloader to be configured and
37289 Some of the bootloaders do not honor every field of
37290 @code{bootloader-configuration}. For instance, the extlinux
37291 bootloader does not support themes and thus ignores the @code{theme}
37294 @deftp {Data Type} bootloader-configuration
37295 The type of a bootloader configuration declaration.
37299 @item @code{bootloader}
37300 @cindex EFI, bootloader
37301 @cindex UEFI, bootloader
37302 @cindex BIOS, bootloader
37303 The bootloader to use, as a @code{bootloader} object. For now
37304 @code{grub-bootloader}, @code{grub-efi-bootloader},
37305 @code{grub-efi-netboot-bootloader}, @code{grub-efi-removable-bootloader},
37306 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
37308 @cindex ARM, bootloaders
37309 @cindex AArch64, bootloaders
37310 Available bootloaders are described in @code{(gnu bootloader @dots{})}
37311 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
37312 of bootloaders for a wide range of ARM and AArch64 systems, using the
37313 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
37315 @vindex grub-efi-bootloader
37316 @code{grub-efi-bootloader} allows to boot on modern systems using the
37317 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
37318 use if the installation image contains a @file{/sys/firmware/efi} directory
37319 when you boot it on your system.
37321 @vindex grub-bootloader
37322 @code{grub-bootloader} allows you to boot in particular Intel-based machines
37323 in ``legacy'' BIOS mode.
37325 @vindex grub-efi-netboot-bootloader
37326 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
37327 through TFTP@. In combination with an NFS root file system this allows you to
37328 build a diskless Guix system.
37330 The installation of the @code{grub-efi-netboot-bootloader} generates the
37331 content of the TFTP root directory at @code{targets} (@pxref{Bootloader
37332 Configuration, @code{targets}}), to be served by a TFTP server. You may
37333 want to mount your TFTP server directories onto the @code{targets} to
37334 move the required files to the TFTP server automatically.
37336 If you plan to use an NFS root file system as well (actually if you mount the
37337 store from an NFS share), then the TFTP server needs to serve the file
37338 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
37339 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
37340 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
37341 files from the store will be accessed by GRUB through TFTP with their normal
37342 store path, for example as
37343 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
37345 Two symlinks are created to make this possible. For each target in the
37346 @code{targets} field, the first symlink is
37347 @samp{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
37348 @file{../../../boot/grub/grub.cfg}, where @samp{target} may be
37349 @file{/boot}. In this case the link is not leaving the served TFTP root
37350 directory, but otherwise it does. The second link is
37351 @samp{target}@file{/gnu/store} and points to @file{../gnu/store}. This
37352 link is leaving the served TFTP root directory.
37354 The assumption behind all this is that you have an NFS server exporting
37355 the root file system for your Guix system, and additionally a TFTP
37356 server exporting your @code{targets} directories—usually a single
37357 @file{/boot}—from that same root file system for your Guix system. In
37358 this constellation the symlinks will work.
37360 For other constellations you will have to program your own bootloader
37361 installer, which then takes care to make necessary files from the store
37362 accessible through TFTP, for example by copying them into the TFTP root
37363 directory to your @code{targets}.
37365 It is important to note that symlinks pointing outside the TFTP root directory
37366 may need to be allowed in the configuration of your TFTP server. Further the
37367 store link exposes the whole store through TFTP@. Both points need to be
37368 considered carefully for security aspects.
37370 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
37371 NFS servers, you also need a properly configured DHCP server to make the booting
37372 over netboot possible. For all this we can currently only recommend you to look
37373 for instructions about @acronym{PXE, Preboot eXecution Environment}.
37375 @vindex grub-efi-removable-bootloader
37376 @code{grub-efi-removable-bootloader} allows you to boot your system from
37377 removable media by writing the GRUB file to the UEFI-specification location of
37378 @file{/EFI/BOOT/BOOTX64.efi} of the boot directory, usually @file{/boot/efi}.
37379 This is also useful for some UEFI firmwares that ``forget'' their configuration
37380 from their non-volatile storage. Like @code{grub-efi-bootloader}, this can only
37381 be used if the @file{/sys/firmware/efi} directory is available.
37384 This @emph{will} overwrite the GRUB file from any other operating systems that
37385 also place their GRUB file in the UEFI-specification location; making them
37389 @item @code{targets}
37390 This is a list of strings denoting the targets onto which to install the
37393 The interpretation of targets depends on the bootloader in question.
37394 For @code{grub-bootloader}, for example, they should be device names
37395 understood by the bootloader @command{installer} command, such as
37396 @code{/dev/sda} or @code{(hd0)} (@pxref{Invoking grub-install,,, grub,
37397 GNU GRUB Manual}). For @code{grub-efi-bootloader} and
37398 @code{grub-efi-removable-bootloader} they should be mount
37399 points of the EFI file system, usually @file{/boot/efi}. For
37400 @code{grub-efi-netboot-bootloader}, @code{targets} should be the mount
37401 points corresponding to TFTP root directories served by your TFTP
37404 @item @code{menu-entries} (default: @code{()})
37405 A possibly empty list of @code{menu-entry} objects (see below), denoting
37406 entries to appear in the bootloader menu, in addition to the current
37407 system entry and the entry pointing to previous system generations.
37409 @item @code{default-entry} (default: @code{0})
37410 The index of the default boot menu entry. Index 0 is for the entry of the
37413 @item @code{timeout} (default: @code{5})
37414 The number of seconds to wait for keyboard input before booting. Set to
37415 0 to boot immediately, and to -1 to wait indefinitely.
37417 @cindex keyboard layout, for the bootloader
37418 @item @code{keyboard-layout} (default: @code{#f})
37419 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
37420 layout, usually US@tie{}English (``qwerty'').
37422 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
37426 This option is currently ignored by bootloaders other than @code{grub} and
37430 @item @code{theme} (default: @var{#f})
37431 The bootloader theme object describing the theme to use. If no theme
37432 is provided, some bootloaders might use a default theme, that's true
37435 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
37436 The output terminals used for the bootloader boot menu, as a list of
37437 symbols. GRUB accepts the values: @code{console}, @code{serial},
37438 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
37439 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
37440 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
37441 configuration,,, grub,GNU GRUB manual}).
37443 @item @code{terminal-inputs} (default: @code{'()})
37444 The input terminals used for the bootloader boot menu, as a list of
37445 symbols. For GRUB, the default is the native platform terminal as
37446 determined at run-time. GRUB accepts the values: @code{console},
37447 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
37448 @code{usb_keyboard}. This field corresponds to the GRUB variable
37449 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
37452 @item @code{serial-unit} (default: @code{#f})
37453 The serial unit used by the bootloader, as an integer from 0 to 3.
37454 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
37455 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
37457 @item @code{serial-speed} (default: @code{#f})
37458 The speed of the serial interface, as an integer. For GRUB, the
37459 default value is chosen at run-time; currently GRUB chooses
37460 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
37462 @item @code{device-tree-support?} (default: @code{#t})
37463 Whether to support Linux @uref{https://en.wikipedia.org/wiki/Devicetree,
37464 device tree} files loading.
37466 This option in enabled by default. In some cases involving the
37467 @code{u-boot} bootloader, where the device tree has already been loaded
37468 in RAM, it can be handy to disable the option by setting it to
37476 Should you want to list additional boot menu entries @i{via} the
37477 @code{menu-entries} field above, you will need to create them with the
37478 @code{menu-entry} form. For example, imagine you want to be able to
37479 boot another distro (hard to imagine!), you can define a menu entry
37484 (label "The Other Distro")
37485 (linux "/boot/old/vmlinux-2.6.32")
37486 (linux-arguments '("root=/dev/sda2"))
37487 (initrd "/boot/old/initrd"))
37492 @deftp {Data Type} menu-entry
37493 The type of an entry in the bootloader menu.
37498 The label to show in the menu---e.g., @code{"GNU"}.
37500 @item @code{linux} (default: @code{#f})
37501 The Linux kernel image to boot, for example:
37504 (file-append linux-libre "/bzImage")
37507 For GRUB, it is also possible to specify a device explicitly in the
37508 file path using GRUB's device naming convention (@pxref{Naming
37509 convention,,, grub, GNU GRUB manual}), for example:
37512 "(hd0,msdos1)/boot/vmlinuz"
37515 If the device is specified explicitly as above, then the @code{device}
37516 field is ignored entirely.
37518 @item @code{linux-arguments} (default: @code{()})
37519 The list of extra Linux kernel command-line arguments---e.g.,
37520 @code{("console=ttyS0")}.
37522 @item @code{initrd} (default: @code{#f})
37523 A G-Expression or string denoting the file name of the initial RAM disk
37524 to use (@pxref{G-Expressions}).
37526 @item @code{device} (default: @code{#f})
37527 The device where the kernel and initrd are to be found---i.e., for GRUB,
37528 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
37530 This may be a file system label (a string), a file system UUID (a
37531 bytevector, @pxref{File Systems}), or @code{#f}, in which case
37532 the bootloader will search the device containing the file specified by
37533 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
37534 must @emph{not} be an OS device name such as @file{/dev/sda1}.
37536 @item @code{multiboot-kernel} (default: @code{#f})
37537 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
37538 manual}). When this field is set, a Multiboot menu-entry is generated.
37542 (file-append mach "/boot/gnumach")
37545 @item @code{multiboot-arguments} (default: @code{()})
37546 The list of extra command-line arguments for the multiboot-kernel.
37548 @item @code{multiboot-modules} (default: @code{()})
37549 The list of commands for loading Multiboot modules. For example:
37552 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
37554 (list (file-append libc "/lib/ld.so.1") "exec"
37558 @item @code{chain-loader} (default: @code{#f})
37559 A string that can be accepted by @code{grub}'s @code{chainloader}
37560 directive. This has no effect if either @code{linux} or
37561 @code{multiboot-kernel} fields are specified. The following is an
37562 example of chainloading a different GNU/Linux system.
37566 (bootloader-configuration
37571 (label "GNU/Linux")
37572 (device (uuid "1C31-A17C" 'fat))
37573 (chain-loader "/EFI/GNULinux/grubx64.efi"))))))
37582 @c FIXME: Write documentation once it's stable.
37583 For now only GRUB has theme support. GRUB themes are created using
37584 the @code{grub-theme} form, which is not fully documented yet.
37586 @deftp {Data Type} grub-theme
37587 Data type representing the configuration of the GRUB theme.
37590 @item @code{gfxmode} (default: @code{'("auto")})
37591 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
37592 @pxref{gfxmode,,, grub, GNU GRUB manual}).
37596 @deffn {Scheme Procedure} grub-theme
37597 Return the default GRUB theme used by the operating system if no
37598 @code{theme} field is specified in @code{bootloader-configuration}
37601 It comes with a fancy background image displaying the GNU and Guix
37605 For example, to override the default resolution, you may use something
37610 (bootloader-configuration
37613 (inherit (grub-theme))
37614 (gfxmode '("1024x786x32" "auto"))))))
37617 @node Invoking guix system
37618 @section Invoking @code{guix system}
37620 Once you have written an operating system declaration as seen in the
37621 previous section, it can be @dfn{instantiated} using the @command{guix
37622 system} command. The synopsis is:
37625 guix system @var{options}@dots{} @var{action} @var{file}
37628 @var{file} must be the name of a file containing an
37629 @code{operating-system} declaration. @var{action} specifies how the
37630 operating system is instantiated. Currently the following values are
37635 Display available service type definitions that match the given regular
37636 expressions, sorted by relevance:
37642 $ guix system search console
37643 name: console-fonts
37644 location: gnu/services/base.scm:806:2
37645 extends: shepherd-root
37646 description: Install the given fonts on the specified ttys (fonts are per
37647 + virtual console on GNU/Linux). The value of this service is a list of
37648 + tty/font pairs. The font can be the name of a font provided by the `kbd'
37649 + package or any valid argument to `setfont', as in this example:
37651 + '(("tty1" . "LatGrkCyr-8x16")
37652 + ("tty2" . (file-append
37654 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
37655 + ("tty3" . (file-append
37657 + "/share/consolefonts/ter-132n"))) ; for HDPI
37661 location: gnu/services/base.scm:1190:2
37662 extends: shepherd-root
37663 description: Provide console login using the `mingetty' program.
37667 location: gnu/services/base.scm:860:2
37669 description: Provide a console log-in service as specified by its
37670 + configuration value, a `login-configuration' object.
37676 As for @command{guix package --search}, the result is written in
37677 @code{recutils} format, which makes it easy to filter the output
37678 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
37680 @cindex service type definition, editing
37681 @cindex editing, service type definition
37683 Edit or view the definition of the given service types.
37685 For example, the command below opens your editor, as specified by the
37686 @env{EDITOR} environment variable, on the definition of the
37687 @code{openssh} service type:
37690 guix system edit openssh
37694 Build the operating system described in @var{file}, activate it, and
37695 switch to it@footnote{This action (and the related actions
37696 @code{switch-generation} and @code{roll-back}) are usable only on
37697 systems already running Guix System.}.
37700 @c The paragraph below refers to the problem discussed at
37701 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
37702 It is highly recommended to run @command{guix pull} once before you run
37703 @command{guix system reconfigure} for the first time (@pxref{Invoking
37704 guix pull}). Failing to do that you would see an older version of Guix
37705 once @command{reconfigure} has completed.
37708 This effects all the configuration specified in @var{file}: user
37709 accounts, system services, global package list, setuid programs, etc.
37710 The command starts system services specified in @var{file} that are not
37711 currently running; if a service is currently running this command will
37712 arrange for it to be upgraded the next time it is stopped (e.g.@: by
37713 @code{herd stop X} or @code{herd restart X}).
37715 This command creates a new generation whose number is one greater than
37716 the current generation (as reported by @command{guix system
37717 list-generations}). If that generation already exists, it will be
37718 overwritten. This behavior mirrors that of @command{guix package}
37719 (@pxref{Invoking guix package}).
37721 It also adds a bootloader menu entry for the new OS configuration,
37722 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
37723 entries for older configurations to a submenu, allowing you to choose
37724 an older system generation at boot time should you need it.
37726 @cindex provenance tracking, of the operating system
37727 Upon completion, the new system is deployed under
37728 @file{/run/current-system}. This directory contains @dfn{provenance
37729 meta-data}: the list of channels in use (@pxref{Channels}) and
37730 @var{file} itself, when available. You can view it by running:
37733 guix system describe
37736 This information is useful should you later want to inspect how this
37737 particular generation was built. In fact, assuming @var{file} is
37738 self-contained, you can later rebuild generation @var{n} of your
37739 operating system with:
37742 guix time-machine \
37743 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
37744 system reconfigure \
37745 /var/guix/profiles/system-@var{n}-link/configuration.scm
37748 You can think of it as some sort of built-in version control! Your
37749 system is not just a binary artifact: @emph{it carries its own source}.
37750 @xref{Service Reference, @code{provenance-service-type}}, for more
37751 information on provenance tracking.
37753 By default, @command{reconfigure} @emph{prevents you from downgrading
37754 your system}, which could (re)introduce security vulnerabilities and
37755 also cause problems with ``stateful'' services such as database
37756 management systems. You can override that behavior by passing
37757 @option{--allow-downgrades}.
37759 @item switch-generation
37760 @cindex generations
37761 Switch to an existing system generation. This action atomically
37762 switches the system profile to the specified system generation. It
37763 also rearranges the system's existing bootloader menu entries. It
37764 makes the menu entry for the specified system generation the default,
37765 and it moves the entries for the other generations to a submenu, if
37766 supported by the bootloader being used. The next time the system
37767 boots, it will use the specified system generation.
37769 The bootloader itself is not being reinstalled when using this
37770 command. Thus, the installed bootloader is used with an updated
37771 configuration file.
37773 The target generation can be specified explicitly by its generation
37774 number. For example, the following invocation would switch to system
37778 guix system switch-generation 7
37781 The target generation can also be specified relative to the current
37782 generation with the form @code{+N} or @code{-N}, where @code{+3} means
37783 ``3 generations ahead of the current generation,'' and @code{-1} means
37784 ``1 generation prior to the current generation.'' When specifying a
37785 negative value such as @code{-1}, you must precede it with @code{--} to
37786 prevent it from being parsed as an option. For example:
37789 guix system switch-generation -- -1
37792 Currently, the effect of invoking this action is @emph{only} to switch
37793 the system profile to an existing generation and rearrange the
37794 bootloader menu entries. To actually start using the target system
37795 generation, you must reboot after running this action. In the future,
37796 it will be updated to do the same things as @command{reconfigure},
37797 like activating and deactivating services.
37799 This action will fail if the specified generation does not exist.
37802 @cindex rolling back
37803 Switch to the preceding system generation. The next time the system
37804 boots, it will use the preceding system generation. This is the inverse
37805 of @command{reconfigure}, and it is exactly the same as invoking
37806 @command{switch-generation} with an argument of @code{-1}.
37808 Currently, as with @command{switch-generation}, you must reboot after
37809 running this action to actually start using the preceding system
37812 @item delete-generations
37813 @cindex deleting system generations
37814 @cindex saving space
37815 Delete system generations, making them candidates for garbage collection
37816 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
37819 This works in the same way as @samp{guix package --delete-generations}
37820 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
37821 arguments, all system generations but the current one are deleted:
37824 guix system delete-generations
37827 You can also select the generations you want to delete. The example below
37828 deletes all the system generations that are more than two months old:
37831 guix system delete-generations 2m
37834 Running this command automatically reinstalls the bootloader with an updated
37835 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
37836 longer lists the generations that have been deleted.
37839 Build the derivation of the operating system, which includes all the
37840 configuration files and programs needed to boot and run the system.
37841 This action does not actually install anything.
37844 Populate the given directory with all the files necessary to run the
37845 operating system specified in @var{file}. This is useful for first-time
37846 installations of Guix System. For instance:
37849 guix system init my-os-config.scm /mnt
37852 copies to @file{/mnt} all the store items required by the configuration
37853 specified in @file{my-os-config.scm}. This includes configuration
37854 files, packages, and so on. It also creates other essential files
37855 needed for the system to operate correctly---e.g., the @file{/etc},
37856 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
37858 This command also installs bootloader on the targets specified in
37859 @file{my-os-config}, unless the @option{--no-bootloader} option was
37863 @cindex virtual machine
37865 @anchor{guix system vm}
37866 Build a virtual machine (VM) that contains the operating system declared
37867 in @var{file}, and return a script to run that VM.
37870 The @code{vm} action and others below
37871 can use KVM support in the Linux-libre kernel. Specifically, if the
37872 machine has hardware virtualization support, the corresponding
37873 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
37874 must exist and be readable and writable by the user and by the
37875 build users of the daemon (@pxref{Build Environment Setup}).
37878 Arguments given to the script are passed to QEMU as in the example
37879 below, which enables networking and requests 1@tie{}GiB of RAM for the
37883 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -nic user,model=virtio-net-pci
37886 It's possible to combine the two steps into one:
37889 $ $(guix system vm my-config.scm) -m 1024 -smp 2 -nic user,model=virtio-net-pci
37892 The VM shares its store with the host system.
37894 By default, the root file system of the VM is mounted volatile; the
37895 @option{--persistent} option can be provided to make it persistent
37896 instead. In that case, the VM disk-image file will be copied from the
37897 store to the @env{TMPDIR} directory to make it writable.
37899 Additional file systems can be shared between the host and the VM using
37900 the @option{--share} and @option{--expose} command-line options: the former
37901 specifies a directory to be shared with write access, while the latter
37902 provides read-only access to the shared directory.
37904 The example below creates a VM in which the user's home directory is
37905 accessible read-only, and where the @file{/exchange} directory is a
37906 read-write mapping of @file{$HOME/tmp} on the host:
37909 guix system vm my-config.scm \
37910 --expose=$HOME --share=$HOME/tmp=/exchange
37913 On GNU/Linux, the default is to boot directly to the kernel; this has
37914 the advantage of requiring only a very tiny root disk image since the
37915 store of the host can then be mounted.
37917 The @option{--full-boot} option forces a complete boot sequence, starting
37918 with the bootloader. This requires more disk space since a root image
37919 containing at least the kernel, initrd, and bootloader data files must
37922 The @option{--image-size} option can be used to specify the size of the
37925 The @option{--no-graphic} option will instruct @command{guix system} to
37926 spawn a headless VM that will use the invoking tty for IO. Among other
37927 things, this enables copy-pasting, and scrollback. Use the @kbd{ctrl-a}
37928 prefix to issue QEMU commands; e.g. @kbd{ctrl-a h} prints a help,
37929 @kbd{ctrl-a x} quits the VM, and @kbd{ctrl-a c} switches between the
37930 QEMU monitor and the VM.
37932 @cindex System images, creation in various formats
37933 @cindex Creating system images in various formats
37935 @cindex image, creating disk images
37936 The @code{image} command can produce various image types. The image
37937 type can be selected using the @option{--image-type} option. It
37938 defaults to @code{efi-raw}. When its value is @code{iso9660}, the
37939 @option{--label} option can be used to specify a volume ID with
37940 @code{image}. By default, the root file system of a disk image is
37941 mounted non-volatile; the @option{--volatile} option can be provided to
37942 make it volatile instead. When using @code{image}, the bootloader
37943 installed on the generated image is taken from the provided
37944 @code{operating-system} definition. The following example demonstrates
37945 how to generate an image that uses the @code{grub-efi-bootloader}
37946 bootloader and boot it with QEMU:
37949 image=$(guix system image --image-type=qcow2 \
37950 gnu/system/examples/lightweight-desktop.tmpl)
37951 cp $image /tmp/my-image.qcow2
37952 chmod +w /tmp/my-image.qcow2
37953 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
37954 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
37957 When using the @code{efi-raw} image type, a raw disk image is produced;
37958 it can be copied as is to a USB stick, for instance. Assuming
37959 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
37960 the image to it using the following command:
37963 # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
37966 The @code{--list-image-types} command lists all the available image
37969 @cindex creating virtual machine images
37970 When using the @code{qcow2} image type, the returned image is in qcow2
37971 format, which the QEMU emulator can efficiently use. @xref{Running Guix
37972 in a VM}, for more information on how to run the image in a virtual
37973 machine. The @code{grub-bootloader} bootloader is always used
37974 independently of what is declared in the @code{operating-system} file
37975 passed as argument. This is to make it easier to work with QEMU, which
37976 uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
37977 in the Master Boot Record (MBR).
37979 @cindex docker-image, creating docker images
37980 When using the @code{docker} image type, a Docker image is produced.
37981 Guix builds the image from scratch, not from a pre-existing Docker base
37982 image. As a result, it contains @emph{exactly} what you define in the
37983 operating system configuration file. You can then load the image and
37984 launch a Docker container using commands like the following:
37987 image_id="$(docker load < guix-system-docker-image.tar.gz)"
37988 container_id="$(docker create $image_id)"
37989 docker start $container_id
37992 This command starts a new Docker container from the specified image. It
37993 will boot the Guix system in the usual manner, which means it will
37994 start any services you have defined in the operating system
37995 configuration. You can get an interactive shell running in the container
37996 using @command{docker exec}:
37999 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
38002 Depending on what you run in the Docker container, it
38003 may be necessary to give the container additional permissions. For
38004 example, if you intend to build software using Guix inside of the Docker
38005 container, you may need to pass the @option{--privileged} option to
38006 @code{docker create}.
38008 Last, the @option{--network} option applies to @command{guix system
38009 docker-image}: it produces an image where network is supposedly shared
38010 with the host, and thus without services like nscd or NetworkManager.
38013 Return a script to run the operating system declared in @var{file}
38014 within a container. Containers are a set of lightweight isolation
38015 mechanisms provided by the kernel Linux-libre. Containers are
38016 substantially less resource-demanding than full virtual machines since
38017 the kernel, shared objects, and other resources can be shared with the
38018 host system; this also means they provide thinner isolation.
38020 Currently, the script must be run as root in order to support more than
38021 a single user and group. The container shares its store with the host
38024 As with the @code{vm} action (@pxref{guix system vm}), additional file
38025 systems to be shared between the host and container can be specified
38026 using the @option{--share} and @option{--expose} options:
38029 guix system container my-config.scm \
38030 --expose=$HOME --share=$HOME/tmp=/exchange
38033 The @option{--share} and @option{--expose} options can also be passed to
38034 the generated script to bind-mount additional directories into the
38038 This option requires Linux-libre 3.19 or newer.
38043 @var{options} can contain any of the common build options (@pxref{Common
38044 Build Options}). In addition, @var{options} can contain one of the
38048 @item --expression=@var{expr}
38049 @itemx -e @var{expr}
38050 Consider the operating-system @var{expr} evaluates to.
38051 This is an alternative to specifying a file which evaluates to an
38053 This is used to generate the Guix system installer @pxref{Building the
38054 Installation Image}).
38056 @item --system=@var{system}
38057 @itemx -s @var{system}
38058 Attempt to build for @var{system} instead of the host system type.
38059 This works as per @command{guix build} (@pxref{Invoking guix build}).
38061 @item --target=@var{triplet}
38062 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
38063 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
38064 configuration triplets,, autoconf, Autoconf}).
38068 Return the derivation file name of the given operating system without
38071 @cindex provenance tracking, of the operating system
38072 @item --save-provenance
38073 As discussed above, @command{guix system init} and @command{guix system
38074 reconfigure} always save provenance information @i{via} a dedicated
38075 service (@pxref{Service Reference, @code{provenance-service-type}}).
38076 However, other commands don't do that by default. If you wish to, say,
38077 create a virtual machine image that contains provenance information, you
38081 guix system image -t qcow2 --save-provenance config.scm
38084 That way, the resulting image will effectively ``embed its own source''
38085 in the form of meta-data in @file{/run/current-system}. With that
38086 information, one can rebuild the image to make sure it really contains
38087 what it pretends to contain; or they could use that to derive a variant
38090 @item --image-type=@var{type}
38091 @itemx -t @var{type}
38092 For the @code{image} action, create an image with given @var{type}.
38094 When this option is omitted, @command{guix system} uses the
38095 @code{efi-raw} image type.
38097 @cindex ISO-9660 format
38098 @cindex CD image format
38099 @cindex DVD image format
38100 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
38101 for burning on CDs and DVDs.
38103 @item --image-size=@var{size}
38104 For the @code{image} action, create an image of the given @var{size}.
38105 @var{size} may be a number of bytes, or it may include a unit as a
38106 suffix (@pxref{Block size, size specifications,, coreutils, GNU
38109 When this option is omitted, @command{guix system} computes an estimate
38110 of the image size as a function of the size of the system declared in
38115 For the @code{container} action, allow containers to access the host network,
38116 that is, do not create a network namespace.
38118 @item --root=@var{file}
38119 @itemx -r @var{file}
38120 Make @var{file} a symlink to the result, and register it as a garbage
38123 @item --skip-checks
38124 Skip pre-installation safety checks.
38126 By default, @command{guix system init} and @command{guix system
38127 reconfigure} perform safety checks: they make sure the file systems that
38128 appear in the @code{operating-system} declaration actually exist
38129 (@pxref{File Systems}), and that any Linux kernel modules that may be
38130 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
38131 RAM Disk}). Passing this option skips these tests altogether.
38133 @item --allow-downgrades
38134 Instruct @command{guix system reconfigure} to allow system downgrades.
38136 By default, @command{reconfigure} prevents you from downgrading your
38137 system. It achieves that by comparing the provenance info of your
38138 system (shown by @command{guix system describe}) with that of your
38139 @command{guix} command (shown by @command{guix describe}). If the
38140 commits for @command{guix} are not descendants of those used for your
38141 system, @command{guix system reconfigure} errors out. Passing
38142 @option{--allow-downgrades} allows you to bypass these checks.
38145 Make sure you understand its security implications before using
38146 @option{--allow-downgrades}.
38150 @cindex on-error strategy
38151 @cindex error strategy
38152 @item --on-error=@var{strategy}
38153 Apply @var{strategy} when an error occurs when reading @var{file}.
38154 @var{strategy} may be one of the following:
38157 @item nothing-special
38158 Report the error concisely and exit. This is the default strategy.
38161 Likewise, but also display a backtrace.
38164 Report the error and enter Guile's debugger. From there, you can run
38165 commands such as @code{,bt} to get a backtrace, @code{,locals} to
38166 display local variable values, and more generally inspect the state of the
38167 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
38168 a list of available debugging commands.
38172 Once you have built, configured, re-configured, and re-re-configured
38173 your Guix installation, you may find it useful to list the operating
38174 system generations available on disk---and that you can choose from the
38175 bootloader boot menu:
38180 Describe the running system generation: its file name, the kernel and
38181 bootloader used, etc., as well as provenance information when available.
38183 The @code{--list-installed} flag is available, with the same
38184 syntax that is used in @command{guix package --list-installed}
38185 (@pxref{Invoking guix package}). When the flag is used,
38186 the description will include a list of packages that are currently
38187 installed in the system profile, with optional filtering based on a
38188 regular expression.
38191 The @emph{running} system generation---referred to by
38192 @file{/run/current-system}---is not necessarily the @emph{current}
38193 system generation---referred to by @file{/var/guix/profiles/system}: it
38194 differs when, for instance, you chose from the bootloader menu to boot
38195 an older generation.
38197 It can also differ from the @emph{booted} system generation---referred
38198 to by @file{/run/booted-system}---for instance because you reconfigured
38199 the system in the meantime.
38202 @item list-generations
38203 List a summary of each generation of the operating system available on
38204 disk, in a human-readable way. This is similar to the
38205 @option{--list-generations} option of @command{guix package}
38206 (@pxref{Invoking guix package}).
38208 Optionally, one can specify a pattern, with the same syntax that is used
38209 in @command{guix package --list-generations}, to restrict the list of
38210 generations displayed. For instance, the following command displays
38211 generations that are up to 10 days old:
38214 $ guix system list-generations 10d
38217 The @code{--list-installed} flag may also be specified, with the same
38218 syntax that is used in @command{guix package --list-installed}. This
38219 may be helpful if trying to determine when a package was added to the
38224 The @command{guix system} command has even more to offer! The following
38225 sub-commands allow you to visualize how your system services relate to
38228 @anchor{system-extension-graph}
38231 @item extension-graph
38232 Emit to standard output the @dfn{service
38233 extension graph} of the operating system defined in @var{file}
38234 (@pxref{Service Composition}, for more information on service
38235 extensions). By default the output is in Dot/Graphviz format, but you
38236 can choose a different format with @option{--graph-backend}, as with
38237 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
38242 $ guix system extension-graph @var{file} | xdot -
38245 shows the extension relations among services.
38248 The @command{dot} program is provided by the @code{graphviz} package.
38251 @anchor{system-shepherd-graph}
38252 @item shepherd-graph
38253 Emit to standard output the @dfn{dependency
38254 graph} of shepherd services of the operating system defined in
38255 @var{file}. @xref{Shepherd Services}, for more information and for an
38258 Again, the default output format is Dot/Graphviz, but you can pass
38259 @option{--graph-backend} to select a different one.
38263 @node Invoking guix deploy
38264 @section Invoking @code{guix deploy}
38266 We've already seen @code{operating-system} declarations used to manage a
38267 machine's configuration locally. Suppose you need to configure multiple
38268 machines, though---perhaps you're managing a service on the web that's
38269 comprised of several servers. @command{guix deploy} enables you to use those
38270 same @code{operating-system} declarations to manage multiple remote hosts at
38271 once as a logical ``deployment''.
38274 The functionality described in this section is still under development
38275 and is subject to change. Get in touch with us on
38276 @email{guix-devel@@gnu.org}!
38280 guix deploy @var{file}
38283 Such an invocation will deploy the machines that the code within @var{file}
38284 evaluates to. As an example, @var{file} might contain a definition like this:
38287 ;; This is a Guix deployment of a "bare bones" setup, with
38288 ;; no X11 display server, to a machine with an SSH daemon
38289 ;; listening on localhost:2222. A configuration such as this
38290 ;; may be appropriate for virtual machine with ports
38291 ;; forwarded to the host's loopback interface.
38293 (use-service-modules networking ssh)
38294 (use-package-modules bootloaders)
38298 (host-name "gnu-deployed")
38299 (timezone "Etc/UTC")
38300 (bootloader (bootloader-configuration
38301 (bootloader grub-bootloader)
38302 (targets '("/dev/vda"))
38303 (terminal-outputs '(console))))
38304 (file-systems (cons (file-system
38306 (device "/dev/vda1")
38308 %base-file-systems))
38310 (append (list (service dhcp-client-service-type)
38311 (service openssh-service-type
38312 (openssh-configuration
38313 (permit-root-login #t)
38314 (allow-empty-passwords? #t))))
38318 (operating-system %system)
38319 (environment managed-host-environment-type)
38320 (configuration (machine-ssh-configuration
38321 (host-name "localhost")
38322 (system "x86_64-linux")
38324 (identity "./id_rsa")
38328 The file should evaluate to a list of @var{machine} objects. This example,
38329 upon being deployed, will create a new generation on the remote system
38330 realizing the @code{operating-system} declaration @code{%system}.
38331 @code{environment} and @code{configuration} specify how the machine should be
38332 provisioned---that is, how the computing resources should be created and
38333 managed. The above example does not create any resources, as a
38334 @code{'managed-host} is a machine that is already running the Guix system and
38335 available over the network. This is a particularly simple case; a more
38336 complex deployment may involve, for example, starting virtual machines through
38337 a Virtual Private Server (VPS) provider. In such a case, a different
38338 @var{environment} type would be used.
38340 Do note that you first need to generate a key pair on the coordinator machine
38341 to allow the daemon to export signed archives of files from the store
38342 (@pxref{Invoking guix archive}), though this step is automatic on Guix
38346 # guix archive --generate-key
38350 Each target machine must authorize the key of the master machine so that it
38351 accepts store items it receives from the coordinator:
38354 # guix archive --authorize < coordinator-public-key.txt
38357 @code{user}, in this example, specifies the name of the user account to log in
38358 as to perform the deployment. Its default value is @code{root}, but root
38359 login over SSH may be forbidden in some cases. To work around this,
38360 @command{guix deploy} can log in as an unprivileged user and employ
38361 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
38362 currently installed on the remote and can be invoked non-interactively as
38363 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
38364 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
38365 be accomplished with the following operating system configuration snippet:
38369 (gnu system)) ;for %sudoers-specification
38371 (define %user "username")
38376 (plain-file "sudoers"
38377 (string-append (plain-file-content %sudoers-specification)
38378 (format #f "~a ALL = NOPASSWD: ALL~%"
38383 For more information regarding the format of the @file{sudoers} file,
38384 consult @command{man sudoers}.
38386 Once you've deployed a system on a set of machines, you may find it
38387 useful to run a command on all of them. The @option{--execute} or
38388 @option{-x} option lets you do that; the example below runs
38389 @command{uname -a} on all the machines listed in the deployment file:
38392 guix deploy @var{file} -x -- uname -a
38395 One thing you may often need to do after deployment is restart specific
38396 services on all the machines, which you can do like so:
38399 guix deploy @var{file} -x -- herd restart @var{service}
38402 The @command{guix deploy -x} command returns zero if and only if the
38403 command succeeded on all the machines.
38405 @c FIXME/TODO: Separate the API doc from the CLI doc.
38407 Below are the data types you need to know about when writing a
38410 @deftp {Data Type} machine
38411 This is the data type representing a single machine in a heterogeneous Guix
38415 @item @code{operating-system}
38416 The object of the operating system configuration to deploy.
38418 @item @code{environment}
38419 An @code{environment-type} describing how the machine should be provisioned.
38421 @item @code{configuration} (default: @code{#f})
38422 An object describing the configuration for the machine's @code{environment}.
38423 If the @code{environment} has a default configuration, @code{#f} may be used.
38424 If @code{#f} is used for an environment with no default configuration,
38425 however, an error will be thrown.
38429 @deftp {Data Type} machine-ssh-configuration
38430 This is the data type representing the SSH client parameters for a machine
38431 with an @code{environment} of @code{managed-host-environment-type}.
38434 @item @code{host-name}
38435 @item @code{build-locally?} (default: @code{#t})
38436 If false, system derivations will be built on the machine being deployed to.
38437 @item @code{system}
38438 The system type describing the architecture of the machine being deployed
38439 to---e.g., @code{"x86_64-linux"}.
38440 @item @code{authorize?} (default: @code{#t})
38441 If true, the coordinator's signing key will be added to the remote's ACL
38443 @item @code{port} (default: @code{22})
38444 @item @code{user} (default: @code{"root"})
38445 @item @code{identity} (default: @code{#f})
38446 If specified, the path to the SSH private key to use to authenticate with the
38449 @item @code{host-key} (default: @code{#f})
38450 This should be the SSH host key of the machine, which looks like this:
38453 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
38456 When @code{host-key} is @code{#f}, the server is authenticated against
38457 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
38460 @item @code{allow-downgrades?} (default: @code{#f})
38461 Whether to allow potential downgrades.
38463 Like @command{guix system reconfigure}, @command{guix deploy} compares
38464 the channel commits currently deployed on the remote host (as returned
38465 by @command{guix system describe}) to those currently in use (as
38466 returned by @command{guix describe}) to determine whether commits
38467 currently in use are descendants of those deployed. When this is not
38468 the case and @code{allow-downgrades?} is false, it raises an error.
38469 This ensures you do not accidentally downgrade remote machines.
38471 @item @code{safety-checks?} (default: @code{#t})
38472 Whether to perform ``safety checks'' before deployment. This includes
38473 verifying that devices and file systems referred to in the operating
38474 system configuration actually exist on the target machine, and making
38475 sure that Linux modules required to access storage devices at boot time
38476 are listed in the @code{initrd-modules} field of the operating system.
38478 These safety checks ensure that you do not inadvertently deploy a system
38479 that would fail to boot. Be careful before turning them off!
38483 @deftp {Data Type} digital-ocean-configuration
38484 This is the data type describing the Droplet that should be created for a
38485 machine with an @code{environment} of @code{digital-ocean-environment-type}.
38488 @item @code{ssh-key}
38489 The path to the SSH private key to use to authenticate with the remote
38490 host. In the future, this field may not exist.
38492 A list of string ``tags'' that uniquely identify the machine. Must be given
38493 such that no two machines in the deployment have the same set of tags.
38494 @item @code{region}
38495 A Digital Ocean region slug, such as @code{"nyc3"}.
38497 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
38498 @item @code{enable-ipv6?}
38499 Whether or not the droplet should be created with IPv6 networking.
38503 @node Running Guix in a VM
38504 @section Running Guix in a Virtual Machine
38506 @cindex virtual machine
38507 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM
38508 image distributed at
38509 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.qcow2}.
38510 This image is a compressed image in QCOW format. You can pass it to an
38511 emulator such as @uref{https://qemu.org/, QEMU} (see below for details).
38513 This image boots the Xfce graphical environment and it contains some
38514 commonly used tools. You can install more software in the image by running
38515 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
38516 also reconfigure the system based on its initial configuration file available
38517 as @file{/run/current-system/configuration.scm} (@pxref{Using the
38518 Configuration System}).
38520 Instead of using this pre-built image, one can also build their own
38521 image using @command{guix system image} (@pxref{Invoking guix system}).
38524 If you built your own image, you must copy it out of the store
38525 (@pxref{The Store}) and give yourself permission to write to the copy
38526 before you can use it. When invoking QEMU, you must choose a system
38527 emulator that is suitable for your hardware platform. Here is a minimal
38528 QEMU invocation that will boot the result of @command{guix system
38529 image -t qcow2} on x86_64 hardware:
38532 $ qemu-system-x86_64 \
38533 -nic user,model=virtio-net-pci \
38534 -enable-kvm -m 2048 \
38535 -device virtio-blk,drive=myhd \
38536 -drive if=none,file=/tmp/qemu-image,id=myhd
38539 Here is what each of these options means:
38542 @item qemu-system-x86_64
38543 This specifies the hardware platform to emulate. This should match the
38546 @item -nic user,model=virtio-net-pci
38547 Enable the unprivileged user-mode network stack. The guest OS can
38548 access the host but not vice versa. This is the simplest way to get the
38549 guest OS online. @code{model} specifies which network device to emulate:
38550 @code{virtio-net-pci} is a special device made for virtualized operating
38551 systems and recommended for most uses. Assuming your hardware platform is
38552 x86_64, you can get a list of available NIC models by running
38553 @command{qemu-system-x86_64 -nic model=help}.
38556 If your system has hardware virtualization extensions, enabling the
38557 virtual machine support (KVM) of the Linux kernel will make things run
38560 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
38562 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
38563 which may be insufficient for some operations.
38565 @item -device virtio-blk,drive=myhd
38566 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
38567 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
38568 better performance than if it were emulating a complete disk drive. See the
38569 QEMU and KVM documentation for more info.
38571 @item -drive if=none,file=/tmp/qemu-image,id=myhd
38572 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
38573 store of the ``myhd'' drive.
38576 The default @command{run-vm.sh} script that is returned by an invocation of
38577 @command{guix system vm} does not add a @command{-nic user} flag by default.
38578 To get network access from within the vm add the @code{(dhcp-client-service)}
38579 to your system definition and start the VM using
38580 @command{$(guix system vm config.scm) -nic user}. An important caveat of using
38581 @command{-nic user} for networking is that @command{ping} will not work, because
38582 it uses the ICMP protocol. You'll have to use a different command to check for
38583 network connectivity, for example @command{guix download}.
38585 @subsection Connecting Through SSH
38589 To enable SSH inside a VM you need to add an SSH server like
38590 @code{openssh-service-type} to your VM (@pxref{Networking Services,
38591 @code{openssh-service-type}}). In addition you need to forward the SSH port,
38592 22 by default, to the host. You can do this with
38595 $(guix system vm config.scm) -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
38598 To connect to the VM you can run
38601 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022 localhost
38604 The @command{-p} tells @command{ssh} the port you want to connect to.
38605 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
38606 every time you modify your @command{config.scm} file and the
38607 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
38608 connection to an unknown host every time you connect.
38611 If you find the above @samp{hostfwd} example not to be working (e.g.,
38612 your SSH client hangs attempting to connect to the mapped port of your
38613 VM), make sure that your Guix System VM has networking support, such as
38614 by using the @code{dhcp-client-service-type} service type.
38617 @subsection Using @command{virt-viewer} with Spice
38619 As an alternative to the default @command{qemu} graphical client you can
38620 use the @command{remote-viewer} from the @command{virt-viewer} package. To
38621 connect pass the @command{-spice port=5930,disable-ticketing} flag to
38622 @command{qemu}. See previous section for further information on how to do this.
38624 Spice also allows you to do some nice stuff like share your clipboard with your
38625 VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
38628 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
38629 -chardev spicevmc,name=vdagent,id=vdagent
38630 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,\
38631 name=com.redhat.spice.0
38634 You'll also need to add the @code{(spice-vdagent-service)} to your
38635 system definition (@pxref{Miscellaneous Services, Spice service}).
38637 @node Defining Services
38638 @section Defining Services
38640 The previous sections show the available services and how one can combine
38641 them in an @code{operating-system} declaration. But how do we define
38642 them in the first place? And what is a service anyway?
38645 * Service Composition:: The model for composing services.
38646 * Service Types and Services:: Types and services.
38647 * Service Reference:: API reference.
38648 * Shepherd Services:: A particular type of service.
38649 * Complex Configurations:: Defining bindings for complex configurations.
38652 @node Service Composition
38653 @subsection Service Composition
38657 Here we define a @dfn{service} as, broadly, something that extends the
38658 functionality of the operating system. Often a service is a process---a
38659 @dfn{daemon}---started when the system boots: a secure shell server, a
38660 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
38661 whose execution can be triggered by another daemon---e.g., an FTP server
38662 started by @command{inetd} or a D-Bus service activated by
38663 @command{dbus-daemon}. Occasionally, a service does not map to a
38664 daemon. For instance, the ``account'' service collects user accounts
38665 and makes sure they exist when the system runs; the ``udev'' service
38666 collects device management rules and makes them available to the eudev
38667 daemon; the @file{/etc} service populates the @file{/etc} directory
38670 @cindex service extensions
38671 Guix system services are connected by @dfn{extensions}. For instance, the
38672 secure shell service @emph{extends} the Shepherd---the
38673 initialization system, running as PID@tie{}1---by giving it the command
38674 lines to start and stop the secure shell daemon (@pxref{Networking
38675 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
38676 service by passing it its @file{.service} specification, and extends the
38677 udev service by passing it device management rules (@pxref{Desktop
38678 Services, @code{upower-service}}); the Guix daemon service extends the
38679 Shepherd by passing it the command lines to start and stop the daemon,
38680 and extends the account service by passing it a list of required build
38681 user accounts (@pxref{Base Services}).
38683 All in all, services and their ``extends'' relations form a directed
38684 acyclic graph (DAG). If we represent services as boxes and extensions
38685 as arrows, a typical system might provide something like this:
38687 @image{images/service-graph,,5in,Typical service extension graph.}
38689 @cindex system service
38690 At the bottom, we see the @dfn{system service}, which produces the
38691 directory containing everything to run and boot the system, as returned
38692 by the @command{guix system build} command. @xref{Service Reference},
38693 to learn about the other service types shown here.
38694 @xref{system-extension-graph, the @command{guix system extension-graph}
38695 command}, for information on how to generate this representation for a
38696 particular operating system definition.
38698 @cindex service types
38699 Technically, developers can define @dfn{service types} to express these
38700 relations. There can be any number of services of a given type on the
38701 system---for instance, a system running two instances of the GNU secure
38702 shell server (lsh) has two instances of @code{lsh-service-type}, with
38703 different parameters.
38705 The following section describes the programming interface for service
38706 types and services.
38708 @node Service Types and Services
38709 @subsection Service Types and Services
38711 A @dfn{service type} is a node in the DAG described above. Let us start
38712 with a simple example, the service type for the Guix build daemon
38713 (@pxref{Invoking guix-daemon}):
38716 (define guix-service-type
38720 (list (service-extension shepherd-root-service-type guix-shepherd-service)
38721 (service-extension account-service-type guix-accounts)
38722 (service-extension activation-service-type guix-activation)))
38723 (default-value (guix-configuration))))
38727 It defines three things:
38731 A name, whose sole purpose is to make inspection and debugging easier.
38734 A list of @dfn{service extensions}, where each extension designates the
38735 target service type and a procedure that, given the parameters of the
38736 service, returns a list of objects to extend the service of that type.
38738 Every service type has at least one service extension. The only
38739 exception is the @dfn{boot service type}, which is the ultimate service.
38742 Optionally, a default value for instances of this type.
38745 In this example, @code{guix-service-type} extends three services:
38748 @item shepherd-root-service-type
38749 The @code{guix-shepherd-service} procedure defines how the Shepherd
38750 service is extended. Namely, it returns a @code{<shepherd-service>}
38751 object that defines how @command{guix-daemon} is started and stopped
38752 (@pxref{Shepherd Services}).
38754 @item account-service-type
38755 This extension for this service is computed by @code{guix-accounts},
38756 which returns a list of @code{user-group} and @code{user-account}
38757 objects representing the build user accounts (@pxref{Invoking
38760 @item activation-service-type
38761 Here @code{guix-activation} is a procedure that returns a gexp, which is
38762 a code snippet to run at ``activation time''---e.g., when the service is
38766 A service of this type is instantiated like this:
38769 (service guix-service-type
38770 (guix-configuration
38772 (extra-options '("--gc-keep-derivations"))))
38775 The second argument to the @code{service} form is a value representing
38776 the parameters of this specific service instance.
38777 @xref{guix-configuration-type, @code{guix-configuration}}, for
38778 information about the @code{guix-configuration} data type. When the
38779 value is omitted, the default value specified by
38780 @code{guix-service-type} is used:
38783 (service guix-service-type)
38786 @code{guix-service-type} is quite simple because it extends other
38787 services but is not extensible itself.
38789 @c @subsubsubsection Extensible Service Types
38791 The service type for an @emph{extensible} service looks like this:
38794 (define udev-service-type
38795 (service-type (name 'udev)
38797 (list (service-extension shepherd-root-service-type
38798 udev-shepherd-service)))
38800 (compose concatenate) ;concatenate the list of rules
38801 (extend (lambda (config rules)
38803 (($ <udev-configuration> udev initial-rules)
38804 (udev-configuration
38805 (udev udev) ;the udev package to use
38806 (rules (append initial-rules rules)))))))))
38809 This is the service type for the
38810 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
38811 management daemon}. Compared to the previous example, in addition to an
38812 extension of @code{shepherd-root-service-type}, we see two new fields:
38816 This is the procedure to @dfn{compose} the list of extensions to
38817 services of this type.
38819 Services can extend the udev service by passing it lists of rules; we
38820 compose those extensions simply by concatenating them.
38823 This procedure defines how the value of the service is @dfn{extended} with
38824 the composition of the extensions.
38826 Udev extensions are composed into a list of rules, but the udev service
38827 value is itself a @code{<udev-configuration>} record. So here, we
38828 extend that record by appending the list of rules it contains to the
38829 list of contributed rules.
38832 This is a string giving an overview of the service type. The string can
38833 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
38834 @command{guix system search} command searches these strings and displays
38835 them (@pxref{Invoking guix system}).
38838 There can be only one instance of an extensible service type such as
38839 @code{udev-service-type}. If there were more, the
38840 @code{service-extension} specifications would be ambiguous.
38842 Still here? The next section provides a reference of the programming
38843 interface for services.
38845 @node Service Reference
38846 @subsection Service Reference
38848 We have seen an overview of service types (@pxref{Service Types and
38849 Services}). This section provides a reference on how to manipulate
38850 services and service types. This interface is provided by the
38851 @code{(gnu services)} module.
38853 @deffn {Scheme Procedure} service @var{type} [@var{value}]
38854 Return a new service of @var{type}, a @code{<service-type>} object (see
38855 below). @var{value} can be any object; it represents the parameters of
38856 this particular service instance.
38858 When @var{value} is omitted, the default value specified by @var{type}
38859 is used; if @var{type} does not specify a default value, an error is
38862 For instance, this:
38865 (service openssh-service-type)
38869 is equivalent to this:
38872 (service openssh-service-type
38873 (openssh-configuration))
38876 In both cases the result is an instance of @code{openssh-service-type}
38877 with the default configuration.
38880 @deffn {Scheme Procedure} service? @var{obj}
38881 Return true if @var{obj} is a service.
38884 @deffn {Scheme Procedure} service-kind @var{service}
38885 Return the type of @var{service}---i.e., a @code{<service-type>} object.
38888 @deffn {Scheme Procedure} service-value @var{service}
38889 Return the value associated with @var{service}. It represents its
38893 Here is an example of how a service is created and manipulated:
38897 (service nginx-service-type
38898 (nginx-configuration
38900 (log-directory log-directory)
38901 (run-directory run-directory)
38902 (file config-file))))
38907 (eq? (service-kind s) nginx-service-type)
38911 The @code{modify-services} form provides a handy way to change the
38912 parameters of some of the services of a list such as
38913 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
38914 evaluates to a list of services. Of course, you could always use
38915 standard list combinators such as @code{map} and @code{fold} to do that
38916 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
38917 @code{modify-services} simply provides a more concise form for this
38920 @deffn {Scheme Syntax} modify-services @var{services} @
38921 (@var{type} @var{variable} => @var{body}) @dots{}
38923 Modify the services listed in @var{services} according to the given
38924 clauses. Each clause has the form:
38927 (@var{type} @var{variable} => @var{body})
38930 where @var{type} is a service type---e.g.,
38931 @code{guix-service-type}---and @var{variable} is an identifier that is
38932 bound within the @var{body} to the service parameters---e.g., a
38933 @code{guix-configuration} instance---of the original service of that
38936 The @var{body} should evaluate to the new service parameters, which will
38937 be used to configure the new service. This new service will replace the
38938 original in the resulting list. Because a service's service parameters
38939 are created using @code{define-record-type*}, you can write a succinct
38940 @var{body} that evaluates to the new service parameters by using the
38941 @code{inherit} feature that @code{define-record-type*} provides.
38943 Clauses can also have the following form:
38946 (delete @var{type})
38949 Such a clause removes all services of the given @var{type} from
38952 @xref{Using the Configuration System}, for example usage.
38956 Next comes the programming interface for service types. This is
38957 something you want to know when writing new service definitions, but not
38958 necessarily when simply looking for ways to customize your
38959 @code{operating-system} declaration.
38961 @deftp {Data Type} service-type
38962 @cindex service type
38963 This is the representation of a @dfn{service type} (@pxref{Service Types
38968 This is a symbol, used only to simplify inspection and debugging.
38970 @item @code{extensions}
38971 A non-empty list of @code{<service-extension>} objects (see below).
38973 @item @code{compose} (default: @code{#f})
38974 If this is @code{#f}, then the service type denotes services that cannot
38975 be extended---i.e., services that do not receive ``values'' from other
38978 Otherwise, it must be a one-argument procedure. The procedure is called
38979 by @code{fold-services} and is passed a list of values collected from
38980 extensions. It may return any single value.
38982 @item @code{extend} (default: @code{#f})
38983 If this is @code{#f}, services of this type cannot be extended.
38985 Otherwise, it must be a two-argument procedure: @code{fold-services}
38986 calls it, passing it the initial value of the service as the first
38987 argument and the result of applying @code{compose} to the extension
38988 values as the second argument. It must return a value that is a valid
38989 parameter value for the service instance.
38991 @item @code{description}
38992 This is a string, possibly using Texinfo markup, describing in a couple
38993 of sentences what the service is about. This string allows users to
38994 find about the service through @command{guix system search}
38995 (@pxref{Invoking guix system}).
38997 @item @code{default-value} (default: @code{&no-default-value})
38998 The default value associated for instances of this service type. This
38999 allows users to use the @code{service} form without its second argument:
39002 (service @var{type})
39005 The returned service in this case has the default value specified by
39009 @xref{Service Types and Services}, for examples.
39012 @deffn {Scheme Procedure} service-extension @var{target-type} @
39014 Return a new extension for services of type @var{target-type}.
39015 @var{compute} must be a one-argument procedure: @code{fold-services}
39016 calls it, passing it the value associated with the service that provides
39017 the extension; it must return a valid value for the target service.
39020 @deffn {Scheme Procedure} service-extension? @var{obj}
39021 Return true if @var{obj} is a service extension.
39024 Occasionally, you might want to simply extend an existing service. This
39025 involves creating a new service type and specifying the extension of
39026 interest, which can be verbose; the @code{simple-service} procedure
39027 provides a shorthand for this.
39029 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
39030 Return a service that extends @var{target} with @var{value}. This works
39031 by creating a singleton service type @var{name}, of which the returned
39032 service is an instance.
39034 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
39038 (simple-service 'my-mcron-job mcron-service-type
39039 #~(job '(next-hour (3)) "guix gc -F 2G"))
39043 At the core of the service abstraction lies the @code{fold-services}
39044 procedure, which is responsible for ``compiling'' a list of services
39045 down to a single directory that contains everything needed to boot and
39046 run the system---the directory shown by the @command{guix system build}
39047 command (@pxref{Invoking guix system}). In essence, it propagates
39048 service extensions down the service graph, updating each node parameters
39049 on the way, until it reaches the root node.
39051 @deffn {Scheme Procedure} fold-services @var{services} @
39052 [#:target-type @var{system-service-type}]
39053 Fold @var{services} by propagating their extensions down to the root of
39054 type @var{target-type}; return the root service adjusted accordingly.
39057 Lastly, the @code{(gnu services)} module also defines several essential
39058 service types, some of which are listed below.
39060 @defvr {Scheme Variable} system-service-type
39061 This is the root of the service graph. It produces the system directory
39062 as returned by the @command{guix system build} command.
39065 @defvr {Scheme Variable} boot-service-type
39066 The type of the ``boot service'', which produces the @dfn{boot script}.
39067 The boot script is what the initial RAM disk runs when booting.
39070 @defvr {Scheme Variable} etc-service-type
39071 The type of the @file{/etc} service. This service is used to create
39072 files under @file{/etc} and can be extended by
39073 passing it name/file tuples such as:
39076 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
39079 In this example, the effect would be to add an @file{/etc/issue} file
39080 pointing to the given file.
39083 @defvr {Scheme Variable} setuid-program-service-type
39084 Type for the ``setuid-program service''. This service collects lists of
39085 executable file names, passed as gexps, and adds them to the set of
39086 setuid and setgid programs on the system (@pxref{Setuid Programs}).
39089 @defvr {Scheme Variable} profile-service-type
39090 Type of the service that populates the @dfn{system profile}---i.e., the
39091 programs under @file{/run/current-system/profile}. Other services can
39092 extend it by passing it lists of packages to add to the system profile.
39095 @cindex provenance tracking, of the operating system
39096 @anchor{provenance-service-type}
39097 @defvr {Scheme Variable} provenance-service-type
39098 This is the type of the service that records @dfn{provenance meta-data}
39099 in the system itself. It creates several files under
39100 @file{/run/current-system}:
39104 This is a ``channel file'' that can be passed to @command{guix pull -C}
39105 or @command{guix time-machine -C}, and which describes the channels used
39106 to build the system, if that information was available
39107 (@pxref{Channels}).
39109 @item configuration.scm
39110 This is the file that was passed as the value for this
39111 @code{provenance-service-type} service. By default, @command{guix
39112 system reconfigure} automatically passes the OS configuration file it
39113 received on the command line.
39116 This contains the same information as the two other files but in a
39117 format that is more readily processable.
39120 In general, these two pieces of information (channels and configuration
39121 file) are enough to reproduce the operating system ``from source''.
39124 This information is necessary to rebuild your operating system, but it
39125 is not always sufficient. In particular, @file{configuration.scm}
39126 itself is insufficient if it is not self-contained---if it refers to
39127 external Guile modules or to extra files. If you want
39128 @file{configuration.scm} to be self-contained, we recommend that modules
39129 or files it refers to be part of a channel.
39131 Besides, provenance meta-data is ``silent'' in the sense that it does
39132 not change the bits contained in your system, @emph{except for the
39133 meta-data bits themselves}. Two different OS configurations or sets of
39134 channels can lead to the same system, bit-for-bit; when
39135 @code{provenance-service-type} is used, these two systems will have
39136 different meta-data and thus different store file names, which makes
39137 comparison less trivial.
39140 This service is automatically added to your operating system
39141 configuration when you use @command{guix system reconfigure},
39142 @command{guix system init}, or @command{guix deploy}.
39145 @defvr {Scheme Variable} linux-loadable-module-service-type
39146 Type of the service that collects lists of packages containing
39147 kernel-loadable modules, and adds them to the set of kernel-loadable
39150 This service type is intended to be extended by other service types,
39154 (simple-service 'installing-module
39155 linux-loadable-module-service-type
39156 (list module-to-install-1
39157 module-to-install-2))
39160 This does not actually load modules at bootup, only adds it to the
39161 kernel profile so that it @emph{can} be loaded by other means.
39164 @node Shepherd Services
39165 @subsection Shepherd Services
39167 @cindex shepherd services
39169 @cindex init system
39170 The @code{(gnu services shepherd)} module provides a way to define
39171 services managed by the GNU@tie{}Shepherd, which is the
39172 initialization system---the first process that is started when the
39173 system boots, also known as PID@tie{}1
39174 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
39176 Services in the Shepherd can depend on each other. For instance, the
39177 SSH daemon may need to be started after the syslog daemon has been
39178 started, which in turn can only happen once all the file systems have
39179 been mounted. The simple operating system defined earlier (@pxref{Using
39180 the Configuration System}) results in a service graph like this:
39182 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
39184 You can actually generate such a graph for any operating system
39185 definition using the @command{guix system shepherd-graph} command
39186 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
39188 The @code{%shepherd-root-service} is a service object representing
39189 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
39190 by passing it lists of @code{<shepherd-service>} objects.
39192 @deftp {Data Type} shepherd-service
39193 The data type representing a service managed by the Shepherd.
39196 @item @code{provision}
39197 This is a list of symbols denoting what the service provides.
39199 These are the names that may be passed to @command{herd start},
39200 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
39201 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
39202 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
39204 @item @code{requirement} (default: @code{'()})
39205 List of symbols denoting the Shepherd services this one depends on.
39207 @cindex one-shot services, for the Shepherd
39208 @item @code{one-shot?} (default: @code{#f})
39209 Whether this service is @dfn{one-shot}. One-shot services stop immediately
39210 after their @code{start} action has completed. @xref{Slots of services,,,
39211 shepherd, The GNU Shepherd Manual}, for more info.
39213 @item @code{respawn?} (default: @code{#t})
39214 Whether to restart the service when it stops, for instance when the
39215 underlying process dies.
39218 @itemx @code{stop} (default: @code{#~(const #f)})
39219 The @code{start} and @code{stop} fields refer to the Shepherd's
39220 facilities to start and stop processes (@pxref{Service De- and
39221 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
39222 G-expressions that get expanded in the Shepherd configuration file
39223 (@pxref{G-Expressions}).
39225 @item @code{actions} (default: @code{'()})
39226 @cindex actions, of Shepherd services
39227 This is a list of @code{shepherd-action} objects (see below) defining
39228 @dfn{actions} supported by the service, in addition to the standard
39229 @code{start} and @code{stop} actions. Actions listed here become available as
39230 @command{herd} sub-commands:
39233 herd @var{action} @var{service} [@var{arguments}@dots{}]
39236 @item @code{auto-start?} (default: @code{#t})
39237 Whether this service should be started automatically by the Shepherd. If it
39238 is @code{#f} the service has to be started manually with @code{herd start}.
39240 @item @code{documentation}
39241 A documentation string, as shown when running:
39244 herd doc @var{service-name}
39247 where @var{service-name} is one of the symbols in @code{provision}
39248 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
39250 @item @code{modules} (default: @code{%default-modules})
39251 This is the list of modules that must be in scope when @code{start} and
39252 @code{stop} are evaluated.
39257 The example below defines a Shepherd service that spawns
39258 @command{syslogd}, the system logger from the GNU Networking Utilities
39259 (@pxref{syslogd invocation, @command{syslogd},, inetutils, GNU
39263 (let ((config (plain-file "syslogd.conf" "@dots{}")))
39265 (documentation "Run the syslog daemon (syslogd).")
39266 (provision '(syslogd))
39267 (requirement '(user-processes))
39268 (start #~(make-forkexec-constructor
39269 (list #$(file-append inetutils "/libexec/syslogd")
39270 "--rcfile" #$config)
39271 #:pid-file "/var/run/syslog.pid"))
39272 (stop #~(make-kill-destructor))))
39275 Key elements in this example are the @code{start} and @code{stop}
39276 fields: they are @dfn{staged} code snippets that use the
39277 @code{make-forkexec-constructor} procedure provided by the Shepherd and
39278 its dual, @code{make-kill-destructor} (@pxref{Service De- and
39279 Constructors,,, shepherd, The GNU Shepherd Manual}). The @code{start}
39280 field will have @command{shepherd} spawn @command{syslogd} with the
39281 given option; note that we pass @code{config} after @option{--rcfile},
39282 which is a configuration file declared above (contents of this file are
39283 omitted). Likewise, the @code{stop} field tells how this service is to
39284 be stopped; in this case, it is stopped by making the @code{kill} system
39285 call on its PID@. Code staging is achieved using G-expressions:
39286 @code{#~} stages code, while @code{#$} ``escapes'' back to host code
39287 (@pxref{G-Expressions}).
39289 @deftp {Data Type} shepherd-action
39290 This is the data type that defines additional actions implemented by a
39291 Shepherd service (see above).
39295 Symbol naming the action.
39297 @item documentation
39298 This is a documentation string for the action. It can be viewed by running:
39301 herd doc @var{service} action @var{action}
39305 This should be a gexp that evaluates to a procedure of at least one argument,
39306 which is the ``running value'' of the service (@pxref{Slots of services,,,
39307 shepherd, The GNU Shepherd Manual}).
39310 The following example defines an action called @code{say-hello} that kindly
39316 (documentation "Say hi!")
39317 (procedure #~(lambda (running . args)
39318 (format #t "Hello, friend! arguments: ~s\n"
39323 Assuming this action is added to the @code{example} service, then you can do:
39326 # herd say-hello example
39327 Hello, friend! arguments: ()
39328 # herd say-hello example a b c
39329 Hello, friend! arguments: ("a" "b" "c")
39332 This, as you can see, is a fairly sophisticated way to say hello.
39333 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
39337 @defvr {Scheme Variable} shepherd-root-service-type
39338 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
39340 This is the service type that extensions target when they want to create
39341 shepherd services (@pxref{Service Types and Services}, for an example).
39342 Each extension must pass a list of @code{<shepherd-service>}. Its
39343 value must be a @code{shepherd-configuration}, as described below.
39346 @deftp {Data Type} shepherd-configuration
39347 This data type represents the Shepherd's configuration.
39350 @item shepherd (default: @code{shepherd})
39351 The Shepherd package to use.
39353 @item services (default: @code{'()})
39354 A list of @code{<shepherd-service>} to start.
39355 You should probably use the service extension
39356 mechanism instead (@pxref{Shepherd Services}).
39360 The following example specifies the Shepherd package for the operating
39366 (services (append (list openssh-service-type))
39370 ;; Use own Shepherd package.
39371 (essential-services
39372 (modify-services (operating-system-default-essential-services
39373 this-operating-system)
39374 (shepherd-root-service-type config => (shepherd-configuration
39376 (shepherd my-shepherd))))))
39379 @defvr {Scheme Variable} %shepherd-root-service
39380 This service represents PID@tie{}1.
39383 @node Complex Configurations
39384 @subsection Complex Configurations
39385 @cindex complex configurations
39386 Some programs might have rather complex configuration files or formats,
39387 and to make it easier to create Scheme bindings for these configuration
39388 files, you can use the utilities defined in the @code{(gnu services
39389 configuration)} module.
39391 The main utility is the @code{define-configuration} macro, which you
39392 will use to define a Scheme record type (@pxref{Record Overview,,,
39393 guile, GNU Guile Reference Manual}). The Scheme record will be
39394 serialized to a configuration file by using @dfn{serializers}, which are
39395 procedures that take some kind of Scheme value and returns a
39396 G-expression (@pxref{G-Expressions}), which should, once serialized to
39397 the disk, return a string. More details are listed below.
39399 @deffn {Scheme Syntax} define-configuration @var{name} @var{clause1} @
39401 Create a record type named @code{@var{name}} that contains the
39402 fields found in the clauses.
39404 A clause can have one of the following forms:
39408 (@var{type} @var{default-value})
39409 @var{documentation})
39412 (@var{type} @var{default-value})
39413 @var{documentation}
39418 @var{documentation})
39422 @var{documentation}
39426 @var{field-name} is an identifier that denotes the name of the field in
39427 the generated record.
39429 @var{type} is the type of the value corresponding to @var{field-name};
39430 since Guile is untyped, a predicate
39431 procedure---@code{@var{type}?}---will be called on the value
39432 corresponding to the field to ensure that the value is of the correct
39433 type. This means that if say, @var{type} is @code{package}, then a
39434 procedure named @code{package?} will be applied on the value to make
39435 sure that it is indeed a @code{<package>} object.
39437 @var{default-value} is the default value corresponding to the field; if
39438 none is specified, the user is forced to provide a value when creating
39439 an object of the record type.
39441 @c XXX: Should these be full sentences or are they allow to be very
39442 @c short like package synopses?
39443 @var{documentation} is a string formatted with Texinfo syntax which
39444 should provide a description of what setting this field does.
39446 @var{serializer} is the name of a procedure which takes two arguments,
39447 the first is the name of the field, and the second is the value
39448 corresponding to the field. The procedure should return a string or
39449 G-expression (@pxref{G-Expressions}) that represents the content that
39450 will be serialized to the configuration file. If none is specified, a
39451 procedure of the name @code{serialize-@var{type}} will be used.
39453 A simple serializer procedure could look like this:
39456 (define (serialize-boolean field-name value)
39457 (let ((value (if value "true" "false")))
39458 #~(string-append #$field-name #$value)))
39461 In some cases multiple different configuration records might be defined
39462 in the same file, but their serializers for the same type might have to
39463 be different, because they have different configuration formats. For
39464 example, the @code{serialize-boolean} procedure for the Getmail service
39465 would have to be different from the one for the Transmission service. To
39466 make it easier to deal with this situation, one can specify a serializer
39467 prefix by using the @code{prefix} literal in the
39468 @code{define-configuration} form. This means that one doesn't have to
39469 manually specify a custom @var{serializer} for every field.
39472 (define (foo-serialize-string field-name value)
39475 (define (bar-serialize-string field-name value)
39478 (define-configuration foo-configuration
39481 "The name of label.")
39484 (define-configuration bar-configuration
39487 "The IPv4 address for this device.")
39491 However, in some cases you might not want to serialize any of the values
39492 of the record, to do this, you can use the @code{no-serialization}
39493 literal. There is also the @code{define-configuration/no-serialization}
39494 macro which is a shorthand of this.
39497 ;; Nothing will be serialized to disk.
39498 (define-configuration foo-configuration
39501 "Some documentation.")
39502 (no-serialization))
39504 ;; The same thing as above.
39505 (define-configuration/no-serialization bar-configuration
39508 "Some documentation."))
39512 @deffn {Scheme Syntax} define-maybe @var{type}
39513 Sometimes a field should not be serialized if the user doesn’t specify a
39514 value. To achieve this, you can use the @code{define-maybe} macro to
39515 define a ``maybe type''; if the value of a maybe type is left unset, or
39516 is set to the @code{%unset-value} value, then it will not be serialized.
39518 When defining a ``maybe type'', the corresponding serializer for the
39519 regular type will be used by default. For example, a field of type
39520 @code{maybe-string} will be serialized using the @code{serialize-string}
39521 procedure by default, you can of course change this by specifying a
39522 custom serializer procedure. Likewise, the type of the value would have
39523 to be a string, or left unspecified.
39526 (define-maybe string)
39528 (define (serialize-string field-name value)
39531 (define-configuration baz-configuration
39533 ;; If set to a string, the `serialize-string' procedure will be used
39534 ;; to serialize the string. Otherwise this field is not serialized.
39536 "The name of this module."))
39539 Like with @code{define-configuration}, one can set a prefix for the
39540 serializer name by using the @code{prefix} literal.
39543 (define-maybe integer
39546 (define (baz-serialize-integer field-name value)
39550 There is also the @code{no-serialization} literal, which when set means
39551 that no serializer will be defined for the ``maybe type'', regardless of
39552 whether its value is set or not.
39553 @code{define-maybe/no-serialization} is a shorthand for specifying the
39554 @code{no-serialization} literal.
39557 (define-maybe/no-serialization symbol)
39559 (define-configuration/no-serialization test-configuration
39566 @deffn (Scheme Procedure) maybe-value-set? @var{value}
39567 Predicate to check whether a user explicitly specified the value of a
39571 @deffn {Scheme Procedure} serialize-configuration @var{configuration} @
39573 Return a G-expression that contains the values corresponding to the
39574 @var{fields} of @var{configuration}, a record that has been generated by
39575 @code{define-configuration}. The G-expression can then be serialized to
39576 disk by using something like @code{mixed-text-file}.
39579 @deffn {Scheme Procedure} empty-serializer @var{field-name} @var{value}
39580 A serializer that just returns an empty string. The
39581 @code{serialize-package} procedure is an alias for this.
39584 Once you have defined a configuration record, you will most likely also
39585 want to document it so that other people know to use it. To help with
39586 that, there are two procedures, both of which are documented below.
39588 @deffn {Scheme Procedure} generate-documentation @var{documentation} @
39589 @var{documentation-name}
39590 Generate a Texinfo fragment from the docstrings in @var{documentation},
39591 a list of @code{(@var{label} @var{fields} @var{sub-documentation} ...)}.
39592 @var{label} should be a symbol and should be the name of the
39593 configuration record. @var{fields} should be a list of all the fields
39594 available for the configuration record.
39596 @var{sub-documentation} is a @code{(@var{field-name}
39597 @var{configuration-name})} tuple. @var{field-name} is the name of the
39598 field which takes another configuration record as its value, and
39599 @var{configuration-name} is the name of that configuration record.
39601 @var{sub-documentation} is only needed if there are nested configuration
39602 records. For example, the @code{getmail-configuration} record
39603 (@pxref{Mail Services}) accepts a @code{getmail-configuration-file}
39604 record in one of its @code{rcfile} field, therefore documentation for
39605 @code{getmail-configuration-file} is nested in
39606 @code{getmail-configuration}.
39609 (generate-documentation
39610 `((getmail-configuration ,getmail-configuration-fields
39611 (rcfile getmail-configuration-file))
39613 'getmail-configuration)
39616 @var{documentation-name} should be a symbol and should be the name of
39617 the configuration record.
39621 @deffn {Scheme Procedure} configuration->documentation
39622 @var{configuration-symbol}
39623 Take @var{configuration-symbol}, the symbol corresponding to the name
39624 used when defining a configuration record with
39625 @code{define-configuration}, and print the Texinfo documentation of its
39626 fields. This is useful if there aren’t any nested configuration records
39627 since it only prints the documentation for the top-level fields.
39630 As of right now, there is no automated way to generate documentation for
39631 configuration records and put them in the manual. Instead, every
39632 time you make a change to the docstrings of a configuration record, you
39633 have to manually call @code{generate-documentation} or
39634 @code{configuration->documentation}, and paste the output into the
39635 @file{doc/guix.texi} file.
39637 @c TODO: Actually test this
39638 Below is an example of a record type created using
39639 @code{define-configuration} and friends.
39642 (use-modules (gnu services)
39644 (gnu services configuration)
39648 ;; Turn field names, which are Scheme symbols into strings
39649 (define (uglify-field-name field-name)
39650 (let ((str (symbol->string field-name)))
39651 ;; field? -> is-field
39652 (if (string-suffix? "?" str)
39653 (string-append "is-" (string-drop-right str 1))
39656 (define (serialize-string field-name value)
39657 #~(string-append #$(uglify-field-name field-name) " = " #$value "\n"))
39659 (define (serialize-integer field-name value)
39660 (serialize-string field-name (number->string value)))
39662 (define (serialize-boolean field-name value)
39663 (serialize-string field-name (if value "true" "false")))
39665 (define (serialize-contact-name field-name value)
39666 #~(string-append "\n[" #$value "]\n"))
39668 (define (list-of-contact-configurations? lst)
39669 (every contact-configuration? lst))
39671 (define (serialize-list-of-contact-configurations field-name value)
39672 #~(string-append #$@@(map (cut serialize-configuration <>
39673 contact-configuration-fields)
39676 (define (serialize-contacts-list-configuration configuration)
39679 #~(string-append "[Owner]\n"
39680 #$(serialize-configuration
39681 configuration contacts-list-configuration-fields))))
39683 (define-maybe integer)
39684 (define-maybe string)
39686 (define-configuration contact-configuration
39689 "The name of the contact."
39690 serialize-contact-name)
39693 "The person's phone number.")
39696 "The person's email address.")
39699 "Whether the person is married."))
39701 (define-configuration contacts-list-configuration
39704 "The name of the owner of this contact list.")
39707 "The owner's email address.")
39709 (list-of-contact-configurations '())
39710 "A list of @@code@{contact-configuation@} records which contain
39711 information about all your contacts."))
39714 A contacts list configuration could then be created like this:
39717 (define my-contacts
39718 (contacts-list-configuration
39720 (email "alice@@example.org")
39722 (list (contact-configuration
39724 (phone-number 1234)
39725 (email "bob@@gnu.org")
39727 (contact-configuration
39729 (phone-number 0000)
39733 After serializing the configuration to disk, the resulting file would
39739 email = alice@@example.org
39742 phone-number = 1234
39743 email = bob@@gnu.org
39752 @node Home Configuration
39753 @chapter Home Configuration
39754 @cindex home configuration
39755 Guix supports declarative configuration of @dfn{home environments} by
39756 utilizing the configuration mechanism described in the previous chapter
39757 (@pxref{Defining Services}), but for user's dotfiles and packages. It
39758 works both on Guix System and foreign distros and allows users to
39759 declare all the packages and services that should be installed and
39760 configured for the user. Once a user has written a file containing
39761 @code{home-environment} record, such a configuration can be
39762 @dfn{instantiated} by an unprivileged user with the @command{guix home}
39763 command (@pxref{Invoking guix home}).
39764 @c Maybe later, it will be possible to make home configuration a part of
39765 @c system configuration to make everything managed by guix system.
39768 The functionality described in this section is still under development
39769 and is subject to change. Get in touch with us on
39770 @email{guix-devel@@gnu.org}!
39773 The user's home environment usually consists of three basic parts:
39774 software, configuration, and state. Software in mainstream distros are
39775 usually installed system-wide, but with GNU Guix most software packages
39776 can be installed on a per-user basis without needing root privileges,
39777 and are thus considered part of the user’s @dfn{home environment}.
39778 Packages on their own are not very useful in many cases, because often they
39779 require some additional configuration, usually config files that reside
39780 in @env{XDG_CONFIG_HOME} (@file{~/.config} by default) or other
39781 directories. Everything else can be considered state, like media files,
39782 application databases, and logs.
39784 Using Guix for managing home environments provides a number of
39789 @item All software can be configured in one language (Guile Scheme),
39790 this gives users the ability to share values between configurations of
39791 different programs.
39793 @item A well-defined home environment is self-contained and can be
39794 created in a declarative and reproducible way---there is no need to grab
39795 external binaries or manually edit some configuration file.
39797 @item After every @command{guix home reconfigure} invocation, a new home
39798 environment generation will be created. This means that users can
39799 rollback to a previous home environment generation so they don’t have to
39800 worry about breaking their configuration.
39802 @item It is possible to manage stateful data with Guix Home, this
39803 includes the ability to automatically clone Git repositories on the
39804 initial setup of the machine, and periodically running commands like
39805 @command{rsync} to sync data with another host. This functionality is
39806 still in an experimental stage, though.
39811 * Declaring the Home Environment:: Customizing your Home.
39812 * Configuring the Shell:: Enabling home environment.
39813 * Home Services:: Specifying home services.
39814 * Invoking guix home:: Instantiating a home configuration.
39817 @node Declaring the Home Environment
39818 @section Declaring the Home Environment
39819 The home environment is configured by providing a
39820 @code{home-environment} declaration in a file that can be passed to the
39821 @command{guix home} command (@pxref{Invoking guix home}). The easiest
39822 way to get started is by generating an initial configuration with
39823 @command{guix home import}:
39826 guix home import ~/src/guix-config
39829 The @command{guix home import} command reads some of the ``dot files''
39830 such as @file{~/.bashrc} found in your home directory and copies them to
39831 the given directory, @file{~/src/guix-config} in this case; it also
39832 reads the contents of your profile, @file{~/.guix-profile}, and, based
39833 on that, it populates @file{~/src/guix-config/home-configuration.scm}
39834 with a Home configuration that resembles your current configuration.
39836 A simple setup can include Bash and a custom text configuration, like in
39837 the example below. Don't be afraid to declare home environment parts,
39838 which overlaps with your current dot files: before installing any
39839 configuration files, Guix Home will back up existing config files to a
39840 separate place in the home directory.
39843 It is highly recommended that you manage your shell or shells with Guix
39844 Home, because it will make sure that all the necessary scripts are
39845 sourced by the shell configuration file. Otherwise you will need to do
39846 it manually. (@pxref{Configuring the Shell}).
39849 @findex home-environment
39851 @include he-config-bare-bones.scm
39854 The @code{packages} field should be self-explanatory, it will install
39855 the list of packages into the user's profile. The most important field
39856 is @code{services}, it contains a list of @dfn{home services}, which are
39857 the basic building blocks of a home environment.
39859 There is no daemon (at least not necessarily) related to a home service,
39860 a home service is just an element that is used to declare part of home
39861 environment and extend other parts of it. The extension mechanism
39862 discussed in the previous chapter (@pxref{Defining Services}) should not
39863 be confused with Shepherd services (@pxref{Shepherd Services}). Using this extension
39864 mechanism and some Scheme code that glues things together gives the user
39865 the freedom to declare their own, very custom, home environments.
39867 @cindex container, for @command{guix home}
39868 Once the configuration looks good, you can first test it in a throw-away
39872 guix home container config.scm
39875 The command above spawns a shell where your home environment is running.
39876 The shell runs in a container, meaning it's isolated from the rest of
39877 the system, so it's a good way to try out your configuration---you can
39878 see if configuration bits are missing or misbehaving, if daemons get
39879 started, and so on. Once you exit that shell, you're back to the prompt
39880 of your original shell ``in the real world''.
39882 Once you have a configuration file that suits your needs, you can
39883 reconfigure your home by running:
39886 guix home reconfigure config.scm
39889 This ``builds'' your home environment and creates @file{~/.guix-home}
39890 pointing to it. Voilà!
39893 Make sure the operating system has elogind, systemd, or a similar
39894 mechanism to create the XDG run-time directory and has the
39895 @env{XDG_RUNTIME_DIR} variable set. Failing that, the
39896 @file{on-first-login} script will not execute anything, and processes
39897 like user Shepherd and its descendants will not start.
39900 @node Configuring the Shell
39901 @section Configuring the Shell
39902 This section is safe to skip if your shell or shells are managed by
39903 Guix Home. Otherwise, read it carefully.
39905 There are a few scripts that must be evaluated by a login shell to
39906 activate the home environment. The shell startup files only read by
39907 login shells often have @code{profile} suffix. For more information
39908 about login shells see @ref{Invoking Bash,,, bash, The GNU Bash
39909 Reference Manual} and see @ref{Bash Startup Files,,, bash, The GNU Bash
39912 The first script that needs to be sourced is @file{setup-environment},
39913 which sets all the necessary environment variables (including variables
39914 declared by the user) and the second one is @file{on-first-login}, which
39915 starts Shepherd for the current user and performs actions declared by
39916 other home services that extends
39917 @code{home-run-on-first-login-service-type}.
39919 Guix Home will always create @file{~/.profile}, which contains the
39923 HOME_ENVIRONMENT=$HOME/.guix-home
39924 . $HOME_ENVIRONMENT/setup-environment
39925 $HOME_ENVIRONMENT/on-first-login
39928 This makes POSIX compliant login shells activate the home environment.
39929 However, in most cases this file won't be read by most modern shells,
39930 because they are run in non POSIX mode by default and have their own
39931 @file{*profile} startup files. For example Bash will prefer
39932 @file{~/.bash_profile} in case it exists and only if it doesn't will it
39933 fallback to @file{~/.profile}. Zsh (if no additional options are
39934 specified) will ignore @file{~/.profile}, even if @file{~/.zprofile}
39937 To make your shell respect @file{~/.profile}, add @code{. ~/.profile} or
39938 @code{source ~/.profile} to the startup file for the login shell. In
39939 case of Bash, it is @file{~/.bash_profile}, and in case of Zsh, it is
39940 @file{~/.zprofile}.
39943 This step is only required if your shell is @emph{not} managed by Guix Home.
39944 Otherwise, everything will be done automatically.
39947 @node Home Services
39948 @section Home Services
39949 @cindex home services
39951 A @dfn{home service} is not necessarily something that has a daemon and
39952 is managed by Shepherd (@pxref{Jump Start,,, shepherd, The GNU Shepherd
39953 Manual}), in most cases it doesn't. It's a simple building block of the
39954 home environment, often declaring a set of packages to be installed in
39955 the home environment profile, a set of config files to be symlinked into
39956 @env{XDG_CONFIG_HOME} (@file{~/.config} by default), and environment
39957 variables to be set by a login shell.
39959 There is a service extension mechanism (@pxref{Service Composition})
39960 which allows home services to extend other home services and utilize
39961 capabilities they provide; for example: declare mcron jobs
39962 (@pxref{Top,,, mcron, GNU@tie{}Mcron}) by extending @ref{Mcron Home
39963 Service}; declare daemons by extending @ref{Shepherd Home Service}; add
39964 commands, which will be invoked on by the Bash by extending
39965 @ref{Shells Home Services, @code{home-bash-service-type}}.
39967 A good way to discover available home services is using the
39968 @command{guix home search} command (@pxref{Invoking guix home}). After
39969 the required home services are found, include its module with the
39970 @code{use-modules} form (@pxref{use-modules,, Using Guile Modules,
39971 guile, The GNU Guile Reference Manual}), or the @code{#:use-modules}
39972 directive (@pxref{define-module,, Creating Guile Modules, guile, The GNU
39973 Guile Reference Manual}) and declare a home service using the
39974 @code{service} function, or extend a service type by declaring a new
39975 service with the @code{simple-service} procedure from @code{(gnu
39979 * Essential Home Services:: Environment variables, packages, on-* scripts.
39980 * Shells: Shells Home Services. POSIX shells, Bash, Zsh.
39981 * Mcron: Mcron Home Service. Scheduled User's Job Execution.
39982 * Shepherd: Shepherd Home Service. Managing User's Daemons.
39983 * SSH: Secure Shell. Setting up the secure shell client.
39984 * Desktop: Desktop Home Services. Services for graphical environments.
39985 * Guix: Guix Home Services. Services for Guix.
39987 @c In addition to that Home Services can provide
39989 @node Essential Home Services
39990 @subsection Essential Home Services
39991 There are a few essential home services defined in
39992 @code{(gnu services)}, they are mostly for internal use and are required
39993 to build a home environment, but some of them will be useful for the end
39996 @cindex environment variables
39998 @defvr {Scheme Variable} home-environment-variables-service-type
39999 The service of this type will be instantiated by every home environment
40000 automatically by default, there is no need to define it, but someone may
40001 want to extend it with a list of pairs to set some environment
40005 (list ("ENV_VAR1" . "value1")
40006 ("ENV_VAR2" . "value2"))
40009 The easiest way to extend a service type, without defining a new service
40010 type is to use the @code{simple-service} helper from @code{(gnu
40014 (simple-service 'some-useful-env-vars-service
40015 home-environment-variables-service-type
40016 `(("LESSHISTFILE" . "$XDG_CACHE_HOME/.lesshst")
40017 ("SHELL" . ,(file-append zsh "/bin/zsh"))
40018 ("USELESS_VAR" . #f)
40019 ("_JAVA_AWT_WM_NONREPARENTING" . #t)))
40022 If you include such a service in you home environment definition, it
40023 will add the following content to the @file{setup-environment} script
40024 (which is expected to be sourced by the login shell):
40027 export LESSHISTFILE=$XDG_CACHE_HOME/.lesshst
40028 export SHELL=/gnu/store/2hsg15n644f0glrcbkb1kqknmmqdar03-zsh-5.8/bin/zsh
40029 export _JAVA_AWT_WM_NONREPARENTING
40033 Make sure that module @code{(gnu packages shells)} is imported with
40034 @code{use-modules} or any other way, this namespace contains the
40035 definition of the @code{zsh} package, which is used in the example
40039 The association list (@pxref{Association Lists, alists, Association
40040 Lists, guile, The GNU Guile Reference manual}) is a data structure
40041 containing key-value pairs, for
40042 @code{home-environment-variables-service-type} the key is always a
40043 string, the value can be a string, string-valued gexp
40044 (@pxref{G-Expressions}), file-like object (@pxref{G-Expressions,
40045 file-like object}) or boolean. For gexps, the variable will be set to
40046 the value of the gexp; for file-like objects, it will be set to the path
40047 of the file in the store (@pxref{The Store}); for @code{#t}, it will
40048 export the variable without any value; and for @code{#f}, it will omit
40053 @defvr {Scheme Variable} home-profile-service-type
40054 The service of this type will be instantiated by every home environment
40055 automatically, there is no need to define it, but you may want to extend
40056 it with a list of packages if you want to install additional packages
40057 into your profile. Other services, which need to make some programs
40058 available to the user will also extend this service type.
40060 The extension value is just a list of packages:
40063 (list htop vim emacs)
40066 The same approach as @code{simple-service} (@pxref{Service Reference,
40067 simple-service}) for @code{home-environment-variables-service-type} can
40068 be used here, too. Make sure that modules containing the specified
40069 packages are imported with @code{use-modules}. To find a package or
40070 information about its module use @command{guix search} (@pxref{Invoking
40071 guix package}). Alternatively, @code{specification->package} can be
40072 used to get the package record from string without importing related
40076 There are few more essential services, but users are not expected to
40079 @defvr {Scheme Variable} home-service-type
40080 The root of home services DAG, it generates a folder, which later will be
40081 symlinked to @file{~/.guix-home}, it contains configurations,
40082 profile with binaries and libraries, and some necessary scripts to glue
40086 @defvr {Scheme Variable} home-run-on-first-login-service-type
40087 The service of this type generates a Guile script, which is expected to
40088 be executed by the login shell. It is only executed if the special flag
40089 file inside @env{XDG_RUNTIME_DIR} hasn't been created, this prevents
40090 redundant executions of the script if multiple login shells are spawned.
40092 It can be extended with a gexp. However, to autostart an application,
40093 users @emph{should not} use this service, in most cases it's better to extend
40094 @code{home-shepherd-service-type} with a Shepherd service
40095 (@pxref{Shepherd Services}), or extend the shell's startup file with
40096 the required command using the appropriate service type.
40099 @defvr {Scheme Variable} home-files-service-type
40100 The service of this type allows to specify a list of files, which will
40101 go to @file{~/.guix-home/files}, usually this directory contains
40102 configuration files (to be more precise it contains symlinks to files in
40103 @file{/gnu/store}), which should be placed in @file{$XDG_CONFIG_DIR} or
40104 in rare cases in @file{$HOME}. It accepts extension values in the
40108 `((".sway/config" ,sway-file-like-object)
40109 (".tmux.conf" ,(local-file "./tmux.conf")))
40112 Each nested list contains two values: a subdirectory and file-like
40113 object. After building a home environment @file{~/.guix-home/files}
40114 will be populated with apropiate content and all nested directories will
40115 be created accordingly, however, those files won't go any further until
40116 some other service will do it. By default a
40117 @code{home-symlink-manager-service-type}, which creates necessary
40118 symlinks in home folder to files from @file{~/.guix-home/files} and
40119 backs up already existing, but clashing configs and other things, is a
40120 part of essential home services (enabled by default), but it's possible
40121 to use alternative services to implement more advanced use cases like
40122 read-only home. Feel free to experiment and share your results.
40125 @defvr {Scheme Variable} home-xdg-configuration-files-service-type
40126 The service is very similiar to @code{home-files-service-type} (and
40127 actually extends it), but used for defining files, which will go to
40128 @file{~/.guix-home/files/.config}, which will be symlinked to
40129 @file{$XDG_CONFIG_DIR} by @code{home-symlink-manager-service-type} (for
40130 example) during activation. It accepts extension values in the
40134 `(("sway/config" ,sway-file-like-object)
40135 ;; -> ~/.guix-home/files/.config/sway/config
40136 ;; -> $XDG_CONFIG_DIR/sway/config (by symlink-manager)
40137 ("tmux/tmux.conf" ,(local-file "./tmux.conf")))
40141 @defvr {Scheme Variable} home-activation-service-type
40142 The service of this type generates a guile script, which runs on every
40143 @command{guix home reconfigure} invocation or any other action, which
40144 leads to the activation of the home environment.
40147 @defvr {Scheme Variable} home-symlink-manager-service-type
40148 The service of this type generates a guile script, which will be
40149 executed during activation of home environment, and do a few following
40154 Reads the content of @file{files/} directory of current and pending home
40158 Cleans up all symlinks created by symlink-manager on previous
40159 activation. Also, sub-directories, which become empty also will be
40163 Creates new symlinks the following way: It looks @file{files/} directory
40164 (usually defined with @code{home-files-service-type},
40165 @code{home-xdg-configuration-files-service-type} and maybe some others),
40166 takes the files from @file{files/.config/} subdirectory and put
40167 respective links in @env{XDG_CONFIG_DIR}. For example symlink for
40168 @file{files/.config/sway/config} will end up in
40169 @file{$XDG_CONFIG_DIR/sway/config}. The rest files in @file{files/}
40170 outside of @file{files/.config/} subdirectory will be treated slightly
40171 different: symlink will just go to @file{$HOME}.
40172 @file{files/.some-program/config} will end up in
40173 @file{$HOME/.some-program/config}.
40176 If some sub-directories are missing, they will be created.
40179 If there is a clashing files on the way, they will be backed up.
40183 symlink-manager is a part of essential home services and is enabled and
40188 @node Shells Home Services
40192 @cindex login shell
40193 @cindex interactive shell
40197 Shells play a quite important role in the environment initialization
40198 process, you can configure them manually as described in section
40199 @ref{Configuring the Shell}, but the recommended way is to use home services
40200 listed below. It's both easier and more reliable.
40202 Each home environment instantiates
40203 @code{home-shell-profile-service-type}, which creates a
40204 @file{~/.profile} startup file for all POSIX-compatible shells. This
40205 file contains all the necessary steps to properly initialize the
40206 environment, but many modern shells like Bash or Zsh prefer their own
40207 startup files, that's why the respective home services
40208 (@code{home-bash-service-type} and @code{home-zsh-service-type}) ensure
40209 that @file{~/.profile} is sourced by @file{~/.bash_profile} and
40210 @file{~/.zprofile}, respectively.
40212 @subsubheading Shell Profile Service
40214 @deftp {Data Type} home-shell-profile-configuration
40215 Available @code{home-shell-profile-configuration} fields are:
40218 @item @code{profile} (default: @code{()}) (type: text-config)
40219 @code{home-shell-profile} is instantiated automatically by
40220 @code{home-environment}, DO NOT create this service manually, it can
40221 only be extended. @code{profile} is a list of file-like objects, which
40222 will go to @file{~/.profile}. By default @file{~/.profile} contains the
40223 initialization code which must be evaluated by the login shell to make
40224 home-environment's profile available to the user, but other commands can
40225 be added to the file if it is really necessary. In most cases shell's
40226 configuration files are preferred places for user's customizations.
40227 Extend home-shell-profile service only if you really know what you do.
40233 @subsubheading Bash Home Service
40235 @anchor{home-bash-configuration}
40236 @deftp {Data Type} home-bash-configuration
40237 Available @code{home-bash-configuration} fields are:
40240 @item @code{package} (default: @code{bash}) (type: package)
40241 The Bash package to use.
40243 @item @code{guix-defaults?} (default: @code{#t}) (type: boolean)
40244 Add sane defaults like reading @file{/etc/bashrc} and coloring the output of
40245 @command{ls} to the top of the @file{.bashrc} file.
40247 @item @code{environment-variables} (default: @code{()}) (type: alist)
40248 Association list of environment variables to set for the Bash session. The
40249 rules for the @code{home-environment-variables-service-type} apply
40250 here (@pxref{Essential Home Services}). The contents of this field will be
40251 added after the contents of the @code{bash-profile} field.
40253 @item @code{aliases} (default: @code{()}) (type: alist)
40254 Association list of aliases to set for the Bash session. The aliases
40255 will be defined after the contents of the @code{bashrc} field has been
40256 put in the @file{.bashrc} file. The alias will automatically be quoted,
40257 so something like this:
40260 '(("ls" . "ls -alF"))
40269 @item @code{bash-profile} (default: @code{()}) (type: text-config)
40270 List of file-like objects, which will be added to @file{.bash_profile}.
40271 Used for executing user's commands at start of login shell (In most
40272 cases the shell started on tty just after login). @file{.bash_login}
40273 won't be ever read, because @file{.bash_profile} always present.
40275 @item @code{bashrc} (default: @code{()}) (type: text-config)
40276 List of file-like objects, which will be added to @file{.bashrc}. Used
40277 for executing user's commands at start of interactive shell (The shell
40278 for interactive usage started by typing @code{bash} or by terminal app
40279 or any other program).
40281 @item @code{bash-logout} (default: @code{()}) (type: text-config)
40282 List of file-like objects, which will be added to @file{.bash_logout}.
40283 Used for executing user's commands at the exit of login shell. It won't
40284 be read in some cases (if the shell terminates by exec'ing another
40285 process for example).
40290 You can extend the Bash service by using the @code{home-bash-extension}
40291 configuration record, whose fields must mirror that of
40292 @code{home-bash-configuration} (@pxref{home-bash-configuration}). The
40293 contents of the extensions will be added to the end of the corresponding
40294 Bash configuration files (@pxref{Bash Startup Files,,, bash, The GNU
40295 Bash Reference Manual}.
40297 For example, here is how you would define a service that extends the
40298 Bash service such that @file{~/.bash_profile} defines an additional
40299 environment variable, @env{PS1}:
40302 (define bash-fancy-prompt-service
40303 (simple-service 'bash-fancy-prompt
40304 home-bash-service-type
40305 (home-bash-extension
40306 (environment-variables
40307 '(("PS1" . "\\u \\wλ "))))))
40310 You would then add @code{bash-fancy-prompt-service} to the list in the
40311 @code{services} field of your @code{home-environment}. The reference of
40312 @code{home-bash-extension} follows.
40314 @deftp {Data Type} home-bash-extension
40315 Available @code{home-bash-extension} fields are:
40318 @item @code{environment-variables} (default: @code{()}) (type: alist)
40319 Additional environment variables to set. These will be combined with the
40320 environment variables from other extensions and the base service to form one
40321 coherent block of environment variables.
40323 @item @code{aliases} (default: @code{()}) (type: alist)
40324 Additional aliases to set. These will be combined with the aliases from
40325 other extensions and the base service.
40327 @item @code{bash-profile} (default: @code{()}) (type: text-config)
40328 Additional text blocks to add to @file{.bash_profile}, which will be combined
40329 with text blocks from other extensions and the base service.
40331 @item @code{bashrc} (default: @code{()}) (type: text-config)
40332 Additional text blocks to add to @file{.bashrc}, which will be combined
40333 with text blocks from other extensions and the base service.
40335 @item @code{bash-logout} (default: @code{()}) (type: text-config)
40336 Additional text blocks to add to @file{.bash_logout}, which will be combined
40337 with text blocks from other extensions and the base service.
40342 @subsubheading Zsh Home Service
40344 @deftp {Data Type} home-zsh-configuration
40345 Available @code{home-zsh-configuration} fields are:
40348 @item @code{package} (default: @code{zsh}) (type: package)
40349 The Zsh package to use.
40351 @item @code{xdg-flavor?} (default: @code{#t}) (type: boolean)
40352 Place all the configs to @file{$XDG_CONFIG_HOME/zsh}. Makes
40353 @file{~/.zshenv} to set @env{ZDOTDIR} to @file{$XDG_CONFIG_HOME/zsh}.
40354 Shell startup process will continue with
40355 @file{$XDG_CONFIG_HOME/zsh/.zshenv}.
40357 @item @code{environment-variables} (default: @code{()}) (type: alist)
40358 Association list of environment variables to set for the Zsh session.
40360 @item @code{zshenv} (default: @code{()}) (type: text-config)
40361 List of file-like objects, which will be added to @file{.zshenv}. Used
40362 for setting user's shell environment variables. Must not contain
40363 commands assuming the presence of tty or producing output. Will be read
40364 always. Will be read before any other file in @env{ZDOTDIR}.
40366 @item @code{zprofile} (default: @code{()}) (type: text-config)
40367 List of file-like objects, which will be added to @file{.zprofile}. Used
40368 for executing user's commands at start of login shell (In most cases the
40369 shell started on tty just after login). Will be read before
40372 @item @code{zshrc} (default: @code{()}) (type: text-config)
40373 List of file-like objects, which will be added to @file{.zshrc}. Used
40374 for executing user's commands at start of interactive shell (The shell
40375 for interactive usage started by typing @code{zsh} or by terminal app or
40376 any other program).
40378 @item @code{zlogin} (default: @code{()}) (type: text-config)
40379 List of file-like objects, which will be added to @file{.zlogin}. Used
40380 for executing user's commands at the end of starting process of login
40383 @item @code{zlogout} (default: @code{()}) (type: text-config)
40384 List of file-like objects, which will be added to @file{.zlogout}. Used
40385 for executing user's commands at the exit of login shell. It won't be
40386 read in some cases (if the shell terminates by exec'ing another process
40393 @node Mcron Home Service
40394 @subsection Scheduled User's Job Execution
40398 @cindex scheduling jobs
40400 The @code{(gnu home services mcron)} module provides an interface to
40401 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
40402 mcron, GNU@tie{}mcron}). The information about system's mcron is
40403 applicable here (@pxref{Scheduled Job Execution}), the only difference
40404 for home services is that they have to be declared in a
40405 @code{home-environment} record instead of an @code{operating-system}
40408 @defvr {Scheme Variable} home-mcron-service-type
40409 This is the type of the @code{mcron} home service, whose value is an
40410 @code{home-mcron-configuration} object. It allows to manage scheduled
40413 This service type can be the target of a service extension that provides
40414 additional job specifications (@pxref{Service Composition}). In other
40415 words, it is possible to define services that provide additional mcron
40419 @deftp {Data Type} home-mcron-configuration
40420 Data type representing the configuration of mcron.
40423 @item @code{mcron} (default: @var{mcron})
40424 The mcron package to use.
40427 This is a list of gexps (@pxref{G-Expressions}), where each gexp
40428 corresponds to an mcron job specification (@pxref{Syntax, mcron job
40429 specifications,, mcron, GNU@tie{}mcron}).
40433 @node Shepherd Home Service
40434 @subsection Managing User Daemons
40436 @cindex shepherd services, for users
40437 The @code{(gnu home services shepherd)} module supports the definitions
40438 of per-user Shepherd services (@pxref{Introduction,,, shepherd, The GNU
40439 Shepherd Manual}). You extend @code{home-shepherd-service-type} with
40440 new services; Guix Home then takes care of starting the @code{shepherd}
40441 daemon for you when you log in, which in turns starts the services you
40444 @defvr {Scheme Variable} home-shepherd-service-type
40445 The service type for the userland Shepherd, which allows one to manage
40446 long-running processes or one-shot tasks. User's Shepherd is not an
40447 init process (PID 1), but almost all other information described in
40448 (@pxref{Shepherd Services}) is applicable here too.
40450 This is the service type that extensions target when they want to create
40451 shepherd services (@pxref{Service Types and Services}, for an example).
40452 Each extension must pass a list of @code{<shepherd-service>}. Its
40453 value must be a @code{home-shepherd-configuration}, as described below.
40456 @deftp {Data Type} home-shepherd-configuration
40457 This data type represents the Shepherd's configuration.
40460 @item shepherd (default: @code{shepherd})
40461 The Shepherd package to use.
40463 @item auto-start? (default: @code{#t})
40464 Whether or not to start Shepherd on first login.
40466 @item services (default: @code{'()})
40467 A list of @code{<shepherd-service>} to start.
40468 You should probably use the service extension
40469 mechanism instead (@pxref{Shepherd Services}).
40474 @subsection Secure Shell
40476 @cindex secure shell client, configuration
40477 @cindex SSH client, configuration
40478 The @uref{https://www.openssh.com, OpenSSH package} includes a client,
40479 the @command{ssh} command, that allows you to connect to remote machines
40480 using the @acronym{SSH, secure shell} protocol. With the @code{(gnu
40481 home services ssh)} module, you can set up OpenSSH so that it works in a
40482 predictable fashion, almost independently of state on the local machine.
40483 To do that, you instantiate @code{home-openssh-service-type} in your
40484 Home configuration, as explained below.
40486 @defvr {Scheme Variable} home-openssh-service-type
40487 This is the type of the service to set up the OpenSSH client. It takes
40488 care of several things:
40492 providing a @file{~/.ssh/config} file based on your configuration so
40493 that @command{ssh} knows about hosts you regularly connect to and their
40494 associated parameters;
40497 providing a @file{~/.ssh/authorized_keys}, which lists public keys that
40498 the local SSH server, @command{sshd}, may accept to connect to this user
40502 optionally providing a @file{~/.ssh/known_hosts} file so that @file{ssh}
40503 can authenticate hosts you connect to.
40506 Here is an example of a service and its configuration that you could add
40507 to the @code{services} field of your @code{home-environment}:
40510 (service home-openssh-service-type
40511 (home-openssh-configuration
40513 (list (openssh-host (name "ci.guix.gnu.org")
40515 (openssh-host (name "chbouib")
40516 (host-name "chbouib.example.org")
40517 (user "supercharlie")
40519 (authorized-keys (list (local-file "alice.pub")))))
40522 The example above lists two hosts and their parameters. For instance,
40523 running @command{ssh chbouib} will automatically connect to
40524 @code{chbouib.example.org} on port 10022, logging in as user
40525 @samp{supercharlie}. Further, it marks the public key in
40526 @file{alice.pub} as authorized for incoming connections.
40528 The value associated with a @code{home-openssh-service-type} instance
40529 must be a @code{home-openssh-configuration} record, as describe below.
40532 @deftp {Data Type} home-openssh-configuration
40533 This is the datatype representing the OpenSSH client and server
40534 configuration in one's home environment. It contains the following
40538 @item @code{hosts} (default: @code{'()})
40539 A list of @code{openssh-host} records specifying host names and
40540 associated connection parameters (see below). This host list goes into
40541 @file{~/.ssh/config}, which @command{ssh} reads at startup.
40543 @item @code{known-hosts} (default: @code{*unspecified*})
40544 This must be either:
40548 @code{*unspecified*}, in which case @code{home-openssh-service-type}
40549 leaves it up to @command{ssh} and to the user to maintain the list of
40550 known hosts at @file{~/.ssh/known_hosts}, or
40553 a list of file-like objects, in which case those are concatenated and
40554 emitted as @file{~/.ssh/known_hosts}.
40557 The @file{~/.ssh/known_hosts} contains a list of host name/host key
40558 pairs that allow @command{ssh} to authenticate hosts you connect to and
40559 to detect possible impersonation attacks. By default, @command{ssh}
40560 updates it in a @dfn{TOFU, trust-on-first-use} fashion, meaning that it
40561 records the host's key in that file the first time you connect to it.
40562 This behavior is preserved when @code{known-hosts} is set to
40563 @code{*unspecified*}.
40565 If you instead provide a list of host keys upfront in the
40566 @code{known-hosts} field, your configuration becomes self-contained and
40567 stateless: it can be replicated elsewhere or at another point in time.
40568 Preparing this list can be relatively tedious though, which is why
40569 @code{*unspecified*} is kept as a default.
40571 @item @code{authorized-keys} (default: @code{'()})
40572 This must be a list of file-like objects, each of which containing an
40573 SSH public key that should be authorized to connect to this machine.
40575 Concretely, these files are concatenated and made available as
40576 @file{~/.ssh/authorized_keys}. If an OpenSSH server, @command{sshd}, is
40577 running on this machine, then it @emph{may} take this file into account:
40578 this is what @command{sshd} does by default, but be aware that it can
40579 also be configured to ignore it.
40583 @c %start of fragment
40585 @deftp {Data Type} openssh-host
40586 Available @code{openssh-host} fields are:
40589 @item @code{name} (type: string)
40590 Name of this host declaration.
40592 @item @code{host-name} (type: maybe-string)
40593 Host name---e.g., @code{"foo.example.org"} or @code{"192.168.1.2"}.
40595 @item @code{address-family} (type: address-family)
40596 Address family to use when connecting to this host: one of
40597 @code{AF_INET} (for IPv4 only), @code{AF_INET6} (for IPv6 only), or
40598 @code{*unspecified*} (allowing any address family).
40600 @item @code{identity-file} (type: maybe-string)
40601 The identity file to use---e.g., @code{"/home/charlie/.ssh/id_ed25519"}.
40603 @item @code{port} (type: maybe-natural-number)
40604 TCP port number to connect to.
40606 @item @code{user} (type: maybe-string)
40607 User name on the remote host.
40609 @item @code{forward-x11?} (default: @code{#f}) (type: boolean)
40610 Whether to forward remote client connections to the local X11 graphical
40613 @item @code{forward-x11-trusted?} (default: @code{#f}) (type: boolean)
40614 Whether remote X11 clients have full access to the original X11
40617 @item @code{forward-agent?} (default: @code{#f}) (type: boolean)
40618 Whether the authentication agent (if any) is forwarded to the remote
40621 @item @code{compression?} (default: @code{#f}) (type: boolean)
40622 Whether to compress data in transit.
40624 @item @code{proxy-command} (type: maybe-string)
40625 The command to use to connect to the server. As an example, a command
40626 to connect via an HTTP proxy at 192.0.2.0 would be: @code{"nc -X connect
40627 -x 192.0.2.0:8080 %h %p"}.
40629 @item @code{host-key-algorithms} (type: maybe-string-list)
40630 The list of accepted host key algorithms---e.g.,
40631 @code{'("ssh-ed25519")}.
40633 @item @code{accepted-key-types} (type: maybe-string-list)
40634 The list of accepted user public key types.
40636 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40637 Extra content appended as-is to this @code{Host} block in
40638 @file{~/.ssh/config}.
40645 @c %end of fragment
40648 @node Desktop Home Services
40649 @subsection Desktop Home Services
40651 The @code{(gnu home services desktop)} module provides services that you
40652 may find useful on ``desktop'' systems running a graphical user
40653 environment such as Xorg.
40655 @defvr {Scheme Variable} home-redshift-service-type
40656 This is the service type for @uref{https://github.com/jonls/redshift,
40657 Redshift}, a program that adjusts the display color temperature
40658 according to the time of day. Its associated value must be a
40659 @code{home-redshift-configuration} record, as shown below.
40661 A typical configuration, where we manually specify the latitude and
40662 longitude, might look like this:
40665 (service home-redshift-service-type
40666 (home-redshift-configuration
40667 (location-provider 'manual)
40668 (latitude 35.81) ;northern hemisphere
40669 (longitude -0.80))) ;west of Greenwich
40673 @deftp {Data Type} home-redshift-configuration
40674 Available @code{home-redshift-configuration} fields are:
40677 @item @code{redshift} (default: @code{redshift}) (type: file-like)
40678 Redshift package to use.
40680 @item @code{location-provider} (default: @code{geoclue2}) (type: symbol)
40681 Geolocation provider---@code{'manual} or @code{'geoclue2}. In the
40682 former case, you must also specify the @code{latitude} and
40683 @code{longitude} fields so Redshift can determine daytime at your place.
40684 In the latter case, the Geoclue system service must be running; it will
40685 be queried for location information.
40687 @item @code{adjustment-method} (default: @code{randr}) (type: symbol)
40688 Color adjustment method.
40690 @item @code{daytime-temperature} (default: @code{6500}) (type: integer)
40691 Daytime color temperature (kelvins).
40693 @item @code{nighttime-temperature} (default: @code{4500}) (type: integer)
40694 Nighttime color temperature (kelvins).
40696 @item @code{daytime-brightness} (type: maybe-inexact-number)
40697 Daytime screen brightness, between 0.1 and 1.0, or left unspecified.
40699 @item @code{nighttime-brightness} (type: maybe-inexact-number)
40700 Nighttime screen brightness, between 0.1 and 1.0, or left unspecified.
40702 @item @code{latitude} (type: maybe-inexact-number)
40703 Latitude, when @code{location-provider} is @code{'manual}.
40705 @item @code{longitude} (type: maybe-inexact-number)
40706 Longitude, when @code{location-provider} is @code{'manual}.
40708 @item @code{dawn-time} (type: maybe-string)
40709 Custom time for the transition from night to day in the
40710 morning---@code{"HH:MM"} format. When specified, solar elevation is not
40711 used to determine the daytime/nighttime period.
40713 @item @code{dusk-time} (type: maybe-string)
40714 Likewise, custom time for the transition from day to night in the
40717 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40718 Extra content appended as-is to the Redshift configuration file. Run
40719 @command{man redshift} for more information about the configuration file
40726 @node Guix Home Services
40727 @subsection Guix Home Services
40729 The @code{(gnu home services guix)} module provides services for
40730 user-specific Guix configuration.
40732 @defvr {Scheme Variable} home-channels-service-type
40733 This is the service type for managing
40734 @file{$XDG_CONFIG_HOME/guix/channels.scm}, the file that controls the
40735 channels received on @command{guix pull} (@pxref{Channels}). Its
40736 associated value is a list of @code{channel} records, defined in the
40737 @code{(guix channels)} module.
40739 Generally, it is better to extend this service than to directly
40740 configure it, as its default value is the default guix channel(s)
40741 defined by @code{%default-channels}. If you configure this service
40742 directly, be sure to include a guix channel. @xref{Specifying
40743 Additional Channels} and @ref{Using a Custom Guix Channel} for more
40746 A typical extension for adding a channel might look like this:
40749 (simple-service 'variant-packages-service
40750 home-channels-service-type
40753 (name 'variant-packages)
40754 (url "https://example.org/variant-packages.git")))
40758 @node Invoking guix home
40759 @section Invoking @code{guix home}
40761 Once you have written a home environment declaration (@pxref{Declaring
40762 the Home Environment,,,,}, it can be @dfn{instantiated} using the
40763 @command{guix home} command. The synopsis is:
40766 guix home @var{options}@dots{} @var{action} @var{file}
40769 @var{file} must be the name of a file containing a
40770 @code{home-environment} declaration. @var{action} specifies how the
40771 home environment is instantiated, but there are few auxiliary actions
40772 which don't instantiate it. Currently the following values are
40777 Display available home service type definitions that match the given
40778 regular expressions, sorted by relevance:
40781 @cindex shell-profile
40785 $ guix home search shell
40786 name: home-shell-profile
40787 location: gnu/home/services/shells.scm:100:2
40788 extends: home-files
40789 description: Create `~/.profile', which is used for environment initialization of POSIX compliant login shells.
40790 + This service type can be extended with a list of file-like objects.
40794 location: gnu/home/services/shells.scm:640:2
40795 extends: home-files home-profile
40796 description: Install and configure Fish, the friendly interactive shell.
40800 location: gnu/home/services/shells.scm:290:2
40801 extends: home-files home-profile
40802 description: Install and configure Zsh.
40806 location: gnu/home/services/shells.scm:508:2
40807 extends: home-files home-profile
40808 description: Install and configure GNU Bash.
40814 As for @command{guix search}, the result is written in
40815 @code{recutils} format, which makes it easy to filter the output
40816 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
40818 @cindex container, for @command{guix home}
40820 Spawn a shell in an isolated environment---a
40821 @dfn{container}---containing your home as specified by @var{file}.
40823 For example, this is how you would start an interactive shell in a
40824 container with your home:
40827 guix home container config.scm
40830 This is a throw-away container where you can lightheartedly fiddle with
40831 files; any changes made within the container, any process started---all
40832 this disappears as soon as you exit that shell.
40834 As with @command{guix shell}, several options control that container:
40839 Enable networking within the container (it is disabled by default).
40841 @item --expose=@var{source}[=@var{target}]
40842 @itemx --share=@var{source}[=@var{target}]
40843 As with @command{guix shell}, make directory @var{source} of the host
40844 system available as @var{target} inside the container---read-only if you
40845 pass @option{--expose}, and writable if you pass @option{--share}
40846 (@pxref{Invoking guix shell, @option{--expose} and @option{--share}}).
40849 Additionally, you can run a command in that container, instead of
40850 spawning an interactive shell. For instance, here is how you would
40851 check which Shepherd services are started in a throw-away home
40855 guix home container config.scm -- herd status
40858 The command to run in the container must come after @code{--} (double
40861 @cindex service type definition, editing
40862 @cindex editing, service type definition
40864 Edit or view the definition of the given Home service types.
40866 For example, the command below opens your editor, as specified by the
40867 @env{EDITOR} environment variable, on the definition of the
40868 @code{home-mcron} service type:
40871 guix home edit home-mcron
40875 Build the home environment described in @var{file}, and switch to it.
40876 Switching means that the activation script will be evaluated and (in
40877 basic scenario) symlinks to configuration files generated from
40878 @code{home-environment} declaration will be created in @file{~}. If the
40879 file with the same path already exists in home folder it will be moved
40880 to @file{~/@var{timestamp}-guix-home-legacy-configs-backup}, where @var{timestamp}
40881 is a current UNIX epoch time.
40884 It is highly recommended to run @command{guix pull} once before you run
40885 @command{guix home reconfigure} for the first time (@pxref{Invoking guix
40889 This effects all the configuration specified in @var{file}. The command
40890 starts Shepherd services specified in @var{file} that are not currently
40891 running; if a service is currently running, this command will arrange
40892 for it to be upgraded the next time it is stopped (e.g.@: by @code{herd
40893 stop @var{service}} or @code{herd restart @var{service}}).
40895 This command creates a new generation whose number is one greater than
40896 the current generation (as reported by @command{guix home
40897 list-generations}). If that generation already exists, it will be
40898 overwritten. This behavior mirrors that of @command{guix package}
40899 (@pxref{Invoking guix package}).
40901 @cindex provenance tracking, of the home environment
40902 Upon completion, the new home is deployed under @file{~/.guix-home}.
40903 This directory contains @dfn{provenance meta-data}: the list of channels
40904 in use (@pxref{Channels}) and @var{file} itself, when available. You
40905 can view the provenance information by running:
40911 This information is useful should you later want to inspect how this
40912 particular generation was built. In fact, assuming @var{file} is
40913 self-contained, you can later rebuild generation @var{n} of your
40914 home environment with:
40917 guix time-machine \
40918 -C /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/channels.scm -- \
40920 /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/configuration.scm
40924 You can think of it as some sort of built-in version control! Your
40925 home is not just a binary artifact: @emph{it carries its own source}.
40926 @c @xref{Service Reference, @code{provenance-service-type}}, for more
40927 @c information on provenance tracking.
40929 @c @footnote{This action (and the related actions
40930 @c @code{switch-generation} and @code{roll-back}) are usable after the
40931 @c home environment is initialized.}.
40933 @item switch-generation
40934 @cindex home generations
40935 Switch to an existing home generation. This action atomically switches
40936 the home profile to the specified home generation.
40938 The target generation can be specified explicitly by its generation
40939 number. For example, the following invocation would switch to home
40943 guix home switch-generation 7
40946 The target generation can also be specified relative to the current
40947 generation with the form @code{+N} or @code{-N}, where @code{+3} means
40948 ``3 generations ahead of the current generation,'' and @code{-1} means
40949 ``1 generation prior to the current generation.'' When specifying a
40950 negative value such as @code{-1}, you must precede it with @code{--} to
40951 prevent it from being parsed as an option. For example:
40954 guix home switch-generation -- -1
40957 This action will fail if the specified generation does not exist.
40960 @cindex rolling back
40961 Switch to the preceding home generation. This is the inverse
40962 of @command{reconfigure}, and it is exactly the same as invoking
40963 @command{switch-generation} with an argument of @code{-1}.
40965 @item delete-generations
40966 @cindex deleting home generations
40967 @cindex saving space
40968 Delete home generations, making them candidates for garbage collection
40969 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
40972 This works in the same way as @samp{guix package --delete-generations}
40973 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
40974 arguments, all home generations but the current one are deleted:
40977 guix home delete-generations
40980 You can also select the generations you want to delete. The example below
40981 deletes all the home generations that are more than two months old:
40984 guix home delete-generations 2m
40988 Build the derivation of the home environment, which includes all the
40989 configuration files and programs needed. This action does not actually
40993 Describe the current home generation: its file name, as well as
40994 provenance information when available.
40996 To show installed packages in the current home generation's profile, the
40997 @code{--list-installed} flag is provided, with the same syntax that is
40998 used in @command{guix package --list-installed} (@pxref{Invoking guix
40999 package}). For instance, the following command shows a table of all the
41000 packages with ``emacs'' in their name that are installed in the current
41001 home generation's profile:
41004 guix home describe --list-installed=emacs
41007 @item list-generations
41008 List a summary of each generation of the home environment available on
41009 disk, in a human-readable way. This is similar to the
41010 @option{--list-generations} option of @command{guix package}
41011 (@pxref{Invoking guix package}).
41013 Optionally, one can specify a pattern, with the same syntax that is used
41014 in @command{guix package --list-generations}, to restrict the list of
41015 generations displayed. For instance, the following command displays
41016 generations that are up to 10 days old:
41019 guix home list-generations 10d
41022 The @code{--list-installed} flag may also be specified, with the same
41023 syntax that is used in @command{guix home describe}. This may be
41024 helpful if trying to determine when a package was added to the home
41028 Generate a @dfn{home environment} from the packages in the default
41029 profile and configuration files found in the user's home directory. The
41030 configuration files will be copied to the specified directory, and a
41031 @file{home-configuration.scm} will be populated with the home
41032 environment. Note that not every home service that exists is supported
41033 (@pxref{Home Services}).
41036 $ guix home import ~/guix-config
41037 guix home: '/home/alice/guix-config' populated with all the Home configuration files
41041 And there's more! @command{guix home} also provides the following
41042 sub-commands to visualize how the services of your home environment
41043 relate to one another:
41046 @cindex service extension graph, of a home environment
41047 @item extension-graph
41048 Emit to standard output the @dfn{service extension graph} of the home
41049 environment defined in @var{file} (@pxref{Service Composition}, for more
41050 information on service extensions). By default the output is in
41051 Dot/Graphviz format, but you can choose a different format with
41052 @option{--graph-backend}, as with @command{guix graph} (@pxref{Invoking
41053 guix graph, @option{--backend}}):
41058 guix home extension-graph @var{file} | xdot -
41061 shows the extension relations among services.
41063 @cindex Shepherd dependency graph, for a home environment
41064 @item shepherd-graph
41065 Emit to standard output the @dfn{dependency graph} of shepherd services
41066 of the home environment defined in @var{file}. @xref{Shepherd
41067 Services}, for more information and for an example graph.
41069 Again, the default output format is Dot/Graphviz, but you can pass
41070 @option{--graph-backend} to select a different one.
41073 @var{options} can contain any of the common build options (@pxref{Common
41074 Build Options}). In addition, @var{options} can contain one of the
41079 @item --expression=@var{expr}
41080 @itemx -e @var{expr}
41081 Consider the home-environment @var{expr} evaluates to.
41082 This is an alternative to specifying a file which evaluates to a home
41085 @item --allow-downgrades
41086 Instruct @command{guix home reconfigure} to allow system downgrades.
41088 Just like @command{guix system}, @command{guix home reconfigure}, by
41089 default, prevents you from downgrading your home to older or unrelated
41090 revisions compared to the channel revisions that were used to deploy
41091 it---those shown by @command{guix home describe}. Using
41092 @option{--allow-downgrades} allows you to bypass that check, at the risk
41093 of downgrading your home---be careful!
41097 @node Documentation
41098 @chapter Documentation
41100 @cindex documentation, searching for
41101 @cindex searching for documentation
41102 @cindex Info, documentation format
41104 @cindex manual pages
41105 In most cases packages installed with Guix come with documentation.
41106 There are two main documentation formats: ``Info'', a browsable
41107 hypertext format used for GNU software, and ``manual pages'' (or ``man
41108 pages''), the linear documentation format traditionally found on Unix.
41109 Info manuals are accessed with the @command{info} command or with Emacs,
41110 and man pages are accessed using @command{man}.
41112 You can look for documentation of software installed on your system by
41113 keyword. For example, the following command searches for information
41114 about ``TLS'' in Info manuals:
41118 "(emacs)Network Security" -- STARTTLS
41119 "(emacs)Network Security" -- TLS
41120 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
41121 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
41126 The command below searches for the same keyword in man
41127 pages@footnote{The database searched by @command{man -k} is only created
41128 in profiles that contain the @code{man-db} package.}:
41132 SSL (7) - OpenSSL SSL/TLS library
41133 certtool (1) - GnuTLS certificate tool
41137 These searches are purely local to your computer so you have the
41138 guarantee that documentation you find corresponds to what you have
41139 actually installed, you can access it off-line, and your privacy is
41142 Once you have these results, you can view the relevant documentation by
41146 $ info "(gnutls)Core TLS API"
41156 Info manuals contain sections and indices as well as hyperlinks like
41157 those found in Web pages. The @command{info} reader (@pxref{Top, Info
41158 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
41159 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
41160 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
41161 Introduction}, for an introduction to Info navigation.
41163 @node Installing Debugging Files
41164 @chapter Installing Debugging Files
41166 @cindex debugging files
41167 Program binaries, as produced by the GCC compilers for instance, are
41168 typically written in the ELF format, with a section containing
41169 @dfn{debugging information}. Debugging information is what allows the
41170 debugger, GDB, to map binary code to source code; it is required to
41171 debug a compiled program in good conditions.
41173 This chapter explains how to use separate debug info when packages
41174 provide it, and how to rebuild packages with debug info when it's
41178 * Separate Debug Info:: Installing 'debug' outputs.
41179 * Rebuilding Debug Info:: Building missing debug info.
41182 @node Separate Debug Info
41183 @section Separate Debug Info
41185 The problem with debugging information is that is takes up a fair amount
41186 of disk space. For example, debugging information for the GNU C Library
41187 weighs in at more than 60 MiB@. Thus, as a user, keeping all the
41188 debugging info of all the installed programs is usually not an option.
41189 Yet, space savings should not come at the cost of an impediment to
41190 debugging---especially in the GNU system, which should make it easier
41191 for users to exert their computing freedom (@pxref{GNU Distribution}).
41193 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
41194 mechanism that allows users to get the best of both worlds: debugging
41195 information can be stripped from the binaries and stored in separate
41196 files. GDB is then able to load debugging information from those files,
41197 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
41200 The GNU distribution takes advantage of this by storing debugging
41201 information in the @code{lib/debug} sub-directory of a separate package
41202 output unimaginatively called @code{debug} (@pxref{Packages with
41203 Multiple Outputs}). Users can choose to install the @code{debug} output
41204 of a package when they need it. For instance, the following command
41205 installs the debugging information for the GNU C Library and for GNU
41209 guix install glibc:debug guile:debug
41212 GDB must then be told to look for debug files in the user's profile, by
41213 setting the @code{debug-file-directory} variable (consider setting it
41214 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
41218 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
41221 From there on, GDB will pick up debugging information from the
41222 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
41224 Below is an alternative GDB script which is useful when working with
41225 other profiles. It takes advantage of the optional Guile integration in
41226 GDB. This snippet is included by default on Guix System in the
41227 @file{~/.gdbinit} file.
41231 (use-modules (gdb))
41232 (execute (string-append "set debug-file-directory "
41233 (or (getenv "GDB_DEBUG_FILE_DIRECTORY")
41234 "~/.guix-profile/lib/debug")))
41238 In addition, you will most likely want GDB to be able to show the source
41239 code being debugged. To do that, you will have to unpack the source
41240 code of the package of interest (obtained with @code{guix build
41241 --source}, @pxref{Invoking guix build}), and to point GDB to that source
41242 directory using the @code{directory} command (@pxref{Source Path,
41243 @code{directory},, gdb, Debugging with GDB}).
41245 @c XXX: keep me up-to-date
41246 The @code{debug} output mechanism in Guix is implemented by the
41247 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
41248 opt-in---debugging information is available only for the packages with
41249 definitions explicitly declaring a @code{debug} output. To check
41250 whether a package has a @code{debug} output, use @command{guix package
41251 --list-available} (@pxref{Invoking guix package}).
41253 Read on for how to deal with packages lacking a @code{debug} output.
41255 @node Rebuilding Debug Info
41256 @section Rebuilding Debug Info
41258 @cindex debugging info, rebuilding
41259 As we saw above, some packages, but not all, provide debugging info in a
41260 @code{debug} output. What can you do when debugging info is missing?
41261 The @option{--with-debug-info} option provides a solution to that: it
41262 allows you to rebuild the package(s) for which debugging info is
41263 missing---and only those---and to graft those onto the application
41264 you're debugging. Thus, while it's not as fast as installing a
41265 @code{debug} output, it is relatively inexpensive.
41267 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
41268 and would like to see what's going on in GLib, a library that's deep
41269 down in its dependency graph. As it turns out, GLib does not have a
41270 @code{debug} output and the backtrace GDB shows is all sadness:
41274 #0 0x00007ffff5f92190 in g_getenv ()
41275 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
41276 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
41277 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
41278 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
41279 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
41280 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
41284 To address that, you install Inkscape linked against a variant GLib that
41285 contains debug info:
41288 guix install inkscape --with-debug-info=glib
41291 This time, debugging will be a whole lot nicer:
41294 $ gdb --args sh -c 'exec inkscape'
41297 Function "g_getenv" not defined.
41298 Make breakpoint pending on future shared library load? (y or [n]) y
41299 Breakpoint 1 (g_getenv) pending.
41301 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
41304 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
41305 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
41306 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
41307 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
41308 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
41314 Note that there can be packages for which @option{--with-debug-info}
41315 will not have the desired effect. @xref{Package Transformation Options,
41316 @option{--with-debug-info}}, for more information.
41318 @node Using TeX and LaTeX
41319 @chapter Using @TeX{} and @LaTeX{}
41321 @cindex @TeX{} packages
41322 @cindex @LaTeX{} packages
41323 Guix provides packages for the @TeX{}, @LaTeX{}, ConTeXt, LuaTeX, and
41324 related typesetting systems, taken from the
41325 @uref{https://www.tug.org/texlive/, @TeX{} Live distribution}. However,
41326 because @TeX{} Live is so huge and because finding your way in this maze
41327 is tricky, we thought that you, dear user, would welcome guidance on how
41328 to deploy the relevant packages so you can compile your @TeX{} and
41329 @LaTeX{} documents.
41331 @TeX{} Live currently comes in two flavors in Guix:
41335 The ``monolithic'' @code{texlive} package: it comes with @emph{every
41336 single @TeX{} Live package} (more than 7,000 of them), but it is huge
41337 (more than 4@tie{}GiB for a single package!).
41340 The ``modular'' @code{texlive-} packages: you install
41341 @code{texlive-base}, which provides core functionality and the main
41342 commands---@command{pdflatex}, @command{dvips}, @command{luatex},
41343 @command{mf}, etc.---together with individual packages that provide just
41344 the features you need---@code{texlive-listings} for the
41345 @code{listings} package, @code{texlive-hyperref} for @code{hyperref},
41346 @code{texlive-beamer} for Beamer, @code{texlive-pgf} for PGF/TikZ,
41350 We recommend using the modular package set because it is much less
41351 resource-hungry. To build your documents, you would use commands such
41355 guix shell texlive-base texlive-wrapfig \
41356 texlive-hyperref texlive-cm-super -- pdflatex doc.tex
41359 You can quickly end up with unreasonably long command lines though. The
41360 solution is to instead write a manifest, for example like this one:
41363 (specifications->manifest
41369 "texlive-microtype"
41370 "texlive-listings" "texlive-hyperref"
41375 ;; Additional fonts.
41376 "texlive-cm-super" "texlive-amsfonts"
41377 "texlive-times" "texlive-helvetic" "texlive-courier"))
41380 You can then pass it to any command with the @option{-m} option:
41383 guix shell -m manifest.scm -- pdflatex doc.tex
41386 @xref{Writing Manifests}, for more on
41387 manifests. In the future, we plan to provide packages for @TeX{} Live
41388 @dfn{collections}---``meta-packages'' such as @code{fontsrecommended},
41389 @code{humanities}, or @code{langarabic} that provide the set of packages
41390 needed in this particular domain. That will allow you to list fewer
41393 The main difficulty here is that using the modular package set forces
41394 you to select precisely the packages that you need. You can use
41395 @command{guix search}, but finding the right package can prove to be
41396 tedious. When a package is missing, @command{pdflatex} and similar
41397 commands fail with an obscure message along the lines of:
41400 doc.tex: File `tikz.sty' not found.
41401 doc.tex:7: Emergency stop.
41405 or, for a missing font:
41408 kpathsea: Running mktexmf phvr7t
41409 ! I can't find file `phvr7t'.
41412 How do you determine what the missing package is? In the first case,
41413 you'll find the answer by running:
41416 $ guix search texlive tikz
41422 In the second case, @command{guix search} turns up nothing. Instead,
41423 you can search the @TeX{} Live package database using the @command{tlmgr}
41427 $ guix shell texlive-base -- tlmgr info phvr7t
41428 tlmgr: cannot find package phvr7t, searching for other matches:
41430 Packages containing `phvr7t' in their title/description:
41432 Packages containing files matching `phvr7t':
41434 texmf-dist/fonts/tfm/adobe/helvetic/phvr7t.tfm
41435 texmf-dist/fonts/tfm/adobe/helvetic/phvr7tn.tfm
41436 texmf-dist/fonts/vf/adobe/helvetic/phvr7t.vf
41437 texmf-dist/fonts/vf/adobe/helvetic/phvr7tn.vf
41439 texmf-dist/tex4ht/ht-fonts/alias/adobe/helvetic/phvr7t.htf
41442 The file is available in the @TeX{} Live @code{helvetic} package, which is
41443 known in Guix as @code{texlive-helvetic}. Quite a ride, but we found
41446 There is one important limitation though: Guix currently provides a
41447 subset of the @TeX{} Live packages. If you stumble upon a missing
41448 package, you can try and import it (@pxref{Invoking guix import}):
41451 guix import texlive @var{package}
41454 Additional options include:
41459 Traverse the dependency graph of the given upstream package recursively
41460 and generate package expressions for all those packages that are not yet
41465 @TeX{} Live packaging is still very much work in progress, but you can
41466 help! @xref{Contributing}, for more information.
41469 @node Security Updates
41470 @chapter Security Updates
41472 @cindex security updates
41473 @cindex security vulnerabilities
41474 Occasionally, important security vulnerabilities are discovered in software
41475 packages and must be patched. Guix developers try hard to keep track of
41476 known vulnerabilities and to apply fixes as soon as possible in the
41477 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
41478 containing only security updates). The @command{guix lint} tool helps
41479 developers find out about vulnerable versions of software packages in the
41484 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
41485 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
41486 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
41490 @xref{Invoking guix lint}, for more information.
41492 Guix follows a functional
41493 package management discipline (@pxref{Introduction}), which implies
41494 that, when a package is changed, @emph{every package that depends on it}
41495 must be rebuilt. This can significantly slow down the deployment of
41496 fixes in core packages such as libc or Bash, since basically the whole
41497 distribution would need to be rebuilt. Using pre-built binaries helps
41498 (@pxref{Substitutes}), but deployment may still take more time than
41502 To address this, Guix implements @dfn{grafts}, a mechanism that allows
41503 for fast deployment of critical updates without the costs associated
41504 with a whole-distribution rebuild. The idea is to rebuild only the
41505 package that needs to be patched, and then to ``graft'' it onto packages
41506 explicitly installed by the user and that were previously referring to
41507 the original package. The cost of grafting is typically very low, and
41508 order of magnitudes lower than a full rebuild of the dependency chain.
41510 @cindex replacements of packages, for grafts
41511 For instance, suppose a security update needs to be applied to Bash.
41512 Guix developers will provide a package definition for the ``fixed''
41513 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
41514 Packages}). Then, the original package definition is augmented with a
41515 @code{replacement} field pointing to the package containing the bug fix:
41522 (replacement bash-fixed)))
41525 From there on, any package depending directly or indirectly on Bash---as
41526 reported by @command{guix gc --requisites} (@pxref{Invoking guix
41527 gc})---that is installed is automatically ``rewritten'' to refer to
41528 @code{bash-fixed} instead of @code{bash}. This grafting process takes
41529 time proportional to the size of the package, usually less than a
41530 minute for an ``average'' package on a recent machine. Grafting is
41531 recursive: when an indirect dependency requires grafting, then grafting
41532 ``propagates'' up to the package that the user is installing.
41534 Currently, the length of the name and version of the graft and that of
41535 the package it replaces (@code{bash-fixed} and @code{bash} in the example
41536 above) must be equal. This restriction mostly comes from the fact that
41537 grafting works by patching files, including binary files, directly.
41538 Other restrictions may apply: for instance, when adding a graft to a
41539 package providing a shared library, the original shared library and its
41540 replacement must have the same @code{SONAME} and be binary-compatible.
41542 The @option{--no-grafts} command-line option allows you to forcefully
41543 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
41547 guix build bash --no-grafts
41551 returns the store file name of the original Bash, whereas:
41558 returns the store file name of the ``fixed'', replacement Bash. This
41559 allows you to distinguish between the two variants of Bash.
41561 To verify which Bash your whole profile refers to, you can run
41562 (@pxref{Invoking guix gc}):
41565 guix gc -R $(readlink -f ~/.guix-profile) | grep bash
41569 @dots{} and compare the store file names that you get with those above.
41570 Likewise for a complete Guix system generation:
41573 guix gc -R $(guix system build my-config.scm) | grep bash
41576 Lastly, to check which Bash running processes are using, you can use the
41577 @command{lsof} command:
41580 lsof | grep /gnu/store/.*bash
41584 @node Bootstrapping
41585 @chapter Bootstrapping
41587 @c Adapted from the ELS 2013 paper.
41589 @cindex bootstrapping
41591 Bootstrapping in our context refers to how the distribution gets built
41592 ``from nothing''. Remember that the build environment of a derivation
41593 contains nothing but its declared inputs (@pxref{Introduction}). So
41594 there's an obvious chicken-and-egg problem: how does the first package
41595 get built? How does the first compiler get compiled?
41597 It is tempting to think of this question as one that only die-hard
41598 hackers may care about. However, while the answer to that question is
41599 technical in nature, its implications are wide-ranging. How the
41600 distribution is bootstrapped defines the extent to which we, as
41601 individuals and as a collective of users and hackers, can trust the
41602 software we run. It is a central concern from the standpoint of
41603 @emph{security} and from a @emph{user freedom} viewpoint.
41605 @cindex bootstrap binaries
41606 The GNU system is primarily made of C code, with libc at its core. The
41607 GNU build system itself assumes the availability of a Bourne shell and
41608 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
41609 `grep'. Furthermore, build programs---programs that run
41610 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
41611 (@pxref{Derivations}). Consequently, to be able to build anything at
41612 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
41613 Binutils, libc, and the other packages mentioned above---the
41614 @dfn{bootstrap binaries}.
41616 These bootstrap binaries are ``taken for granted'', though we can also
41617 re-create them if needed (@pxref{Preparing to Use the Bootstrap
41621 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
41622 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
41625 @node Reduced Binary Seed Bootstrap
41626 @section The Reduced Binary Seed Bootstrap
41628 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
41629 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
41630 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
41631 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
41632 ``taken for granted.''
41634 Taking the bootstrap binaries for granted means that we consider them to
41635 be a correct and trustworthy ``seed'' for building the complete system.
41636 Therein lies a problem: the combined size of these bootstrap binaries is
41637 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
41638 or even inspecting these is next to impossible.
41640 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
41641 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
41642 Source Bootstrap'' and while we are working towards that goal it would
41643 be hyperbole to use that term for what we do now.}.
41645 The Reduced Binary Seed bootstrap removes the most critical tools---from a
41646 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
41647 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
41648 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
41649 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
41651 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
41652 C Library are built from source. From here on the more traditional
41653 bootstrap process resumes. This approach has reduced the bootstrap
41654 binaries in size to about 145MB in Guix v1.1.
41656 The next step that Guix has taken is to replace the shell and all its
41657 utilities with implementations in Guile Scheme, the @emph{Scheme-only
41658 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
41659 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
41660 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
41661 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
41662 removed are now built from source.
41664 Building the GNU System from source is currently only possible by adding
41665 some historical GNU packages as intermediate steps@footnote{Packages
41666 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
41667 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
41668 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
41669 and GNU packages become more bootstrappable again (e.g., new releases of
41670 GNU Sed will also ship as gzipped tarballs again, as alternative to the
41671 hard to bootstrap @code{xz}-compression), this set of added packages can
41672 hopefully be reduced again.
41674 The graph below shows the resulting dependency graph for
41675 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
41676 traditional bootstrap of the rest of the Guix System.
41678 @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
41679 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
41681 The only significant binary bootstrap seeds that remain@footnote{
41682 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
41683 together with @code{mes}.} are a Scheme interpreter and a Scheme
41684 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
41685 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
41686 to get Guile running.}.
41688 This further reduction has brought down the size of the binary seed to
41689 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
41691 Work is ongoing to remove all binary blobs from our free software
41692 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
41693 is work to bring these bootstraps to the @code{arm-linux} and
41694 @code{aarch64-linux} architectures and to the Hurd.
41696 If you are interested, join us on @samp{#bootstrappable} on the Freenode
41697 IRC network or discuss on @email{bug-mes@@gnu.org} or
41698 @email{gash-devel@@nongnu.org}.
41700 @node Preparing to Use the Bootstrap Binaries
41701 @section Preparing to Use the Bootstrap Binaries
41703 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
41704 @c large image, it's hard to scroll. Oh well.
41705 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
41707 The figure above shows the very beginning of the dependency graph of the
41708 distribution, corresponding to the package definitions of the @code{(gnu
41709 packages bootstrap)} module. A similar figure can be generated with
41710 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
41713 guix graph -t derivation \
41714 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
41715 | dot -Tps > gcc.ps
41718 or, for the further Reduced Binary Seed bootstrap
41721 guix graph -t derivation \
41722 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
41723 | dot -Tps > mes.ps
41726 At this level of detail, things are
41727 slightly complex. First, Guile itself consists of an ELF executable,
41728 along with many source and compiled Scheme files that are dynamically
41729 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
41730 tarball shown in this graph. This tarball is part of Guix's ``source''
41731 distribution, and gets inserted into the store with @code{add-to-store}
41732 (@pxref{The Store}).
41734 But how do we write a derivation that unpacks this tarball and adds it
41735 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
41736 derivation---the first one that gets built---uses @code{bash} as its
41737 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
41738 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
41739 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
41740 the Guix source distribution, whose sole purpose is to allow the Guile
41741 tarball to be unpacked.
41743 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
41744 Guile that can be used to run subsequent build programs. Its first task
41745 is to download tarballs containing the other pre-built binaries---this
41746 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
41747 @code{ftp-client.scm} are used for this purpose. The
41748 @code{module-import.drv} derivations import those modules in a directory
41749 in the store, using the original layout. The
41750 @code{module-import-compiled.drv} derivations compile those modules, and
41751 write them in an output directory with the right layout. This
41752 corresponds to the @code{#:modules} argument of
41753 @code{build-expression->derivation} (@pxref{Derivations}).
41755 Finally, the various tarballs are unpacked by the derivations
41756 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
41757 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
41758 point we have a working C tool chain.
41760 @unnumberedsec Building the Build Tools
41762 Bootstrapping is complete when we have a full tool chain that does not
41763 depend on the pre-built bootstrap tools discussed above. This
41764 no-dependency requirement is verified by checking whether the files of
41765 the final tool chain contain references to the @file{/gnu/store}
41766 directories of the bootstrap inputs. The process that leads to this
41767 ``final'' tool chain is described by the package definitions found in
41768 the @code{(gnu packages commencement)} module.
41770 The @command{guix graph} command allows us to ``zoom out'' compared to
41771 the graph above, by looking at the level of package objects instead of
41772 individual derivations---remember that a package may translate to
41773 several derivations, typically one derivation to download its source,
41774 one to build the Guile modules it needs, and one to actually build the
41775 package from source. The command:
41778 guix graph -t bag \
41779 -e '(@@@@ (gnu packages commencement)
41780 glibc-final-with-bootstrap-bash)' | xdot -
41784 displays the dependency graph leading to the ``final'' C
41785 library@footnote{You may notice the @code{glibc-intermediate} label,
41786 suggesting that it is not @emph{quite} final, but as a good
41787 approximation, we will consider it final.}, depicted below.
41789 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
41791 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
41792 The first tool that gets built with the bootstrap binaries is
41793 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
41794 for all the following packages. From there Findutils and Diffutils get
41797 Then come the first-stage Binutils and GCC, built as pseudo cross
41798 tools---i.e., with @option{--target} equal to @option{--host}. They are
41799 used to build libc. Thanks to this cross-build trick, this libc is
41800 guaranteed not to hold any reference to the initial tool chain.
41802 From there the final Binutils and GCC (not shown above) are built. GCC
41803 uses @command{ld} from the final Binutils, and links programs against
41804 the just-built libc. This tool chain is used to build the other
41805 packages used by Guix and by the GNU Build System: Guile, Bash,
41808 And voilà! At this point we have the complete set of build tools that
41809 the GNU Build System expects. These are in the @code{%final-inputs}
41810 variable of the @code{(gnu packages commencement)} module, and are
41811 implicitly used by any package that uses @code{gnu-build-system}
41812 (@pxref{Build Systems, @code{gnu-build-system}}).
41815 @unnumberedsec Building the Bootstrap Binaries
41817 @cindex bootstrap binaries
41818 Because the final tool chain does not depend on the bootstrap binaries,
41819 those rarely need to be updated. Nevertheless, it is useful to have an
41820 automated way to produce them, should an update occur, and this is what
41821 the @code{(gnu packages make-bootstrap)} module provides.
41823 The following command builds the tarballs containing the bootstrap binaries
41824 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
41825 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
41826 and Guile, and a tarball containing a mixture of Coreutils and other basic
41827 command-line tools):
41830 guix build bootstrap-tarballs
41833 The generated tarballs are those that should be referred to in the
41834 @code{(gnu packages bootstrap)} module mentioned at the beginning of
41837 Still here? Then perhaps by now you've started to wonder: when do we
41838 reach a fixed point? That is an interesting question! The answer is
41839 unknown, but if you would like to investigate further (and have
41840 significant computational and storage resources to do so), then let us
41843 @unnumberedsec Reducing the Set of Bootstrap Binaries
41845 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
41846 binary code! Why is that a problem? It's a problem because these big chunks
41847 of binary code are practically non-auditable, which makes it hard to establish
41848 what source code produced them. Every unauditable binary also leaves us
41849 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
41850 paper @emph{Reflections on Trusting Trust}.
41852 This is mitigated by the fact that our bootstrap binaries were generated
41853 from an earlier Guix revision. Nevertheless it lacks the level of
41854 transparency that we get in the rest of the package dependency graph,
41855 where Guix always gives us a source-to-binary mapping. Thus, our goal
41856 is to reduce the set of bootstrap binaries to the bare minimum.
41858 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
41859 on-going projects to do that. One of these is about replacing the
41860 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
41861 of increasing complexity, which could be built from source starting from
41862 a simple and auditable assembler.
41864 Our first major achievement is the replacement of of GCC, the GNU C Library
41865 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
41866 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
41867 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
41868 bootstrapped yet and thus we inject them as binary seeds. We call this the
41869 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
41870 binaries! Also, it has eliminated the C compiler binary; i686-linux and
41871 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
41873 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
41874 also looking at any other bootstrap binaries. Your help is welcome!
41877 @chapter Porting to a New Platform
41879 As discussed above, the GNU distribution is self-contained, and
41880 self-containment is achieved by relying on pre-built ``bootstrap
41881 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
41882 operating system kernel, CPU architecture, and application binary
41883 interface (ABI). Thus, to port the distribution to a platform that is
41884 not yet supported, one must build those bootstrap binaries, and update
41885 the @code{(gnu packages bootstrap)} module to use them on that platform.
41887 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
41888 When everything goes well, and assuming the GNU tool chain supports the
41889 target platform, this can be as simple as running a command like this
41893 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
41896 For this to work, it is first required to register a new platform as
41897 defined in the @code{(guix platform)} module. A platform is making the
41898 connection between a GNU triplet (@pxref{Specifying Target Triplets, GNU
41899 configuration triplets,, autoconf, Autoconf}), the equivalent
41900 @var{system} in Nix notation, the name of the
41901 @var{glibc-dynamic-linker}, and the corresponding Linux architecture
41902 name if applicable.
41904 Once the bootstrap tarball are built, the @code{(gnu packages
41905 bootstrap)} module needs to be updated to refer to these binaries on the
41906 target platform. That is, the hashes and URLs of the bootstrap tarballs
41907 for the new platform must be added alongside those of the currently
41908 supported platforms. The bootstrap Guile tarball is treated specially:
41909 it is expected to be available locally, and @file{gnu/local.mk} has
41910 rules to download it for the supported architectures; a rule for the new
41911 platform must be added as well.
41913 In practice, there may be some complications. First, it may be that the
41914 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
41915 above) is not recognized by all the GNU tools. Typically, glibc
41916 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
41917 configure flag (see @code{gcc.scm} for examples of how to handle this).
41918 Second, some of the required packages could fail to build for that
41919 platform. Lastly, the generated binaries could be broken for some
41922 @c *********************************************************************
41923 @include contributing.texi
41925 @c *********************************************************************
41926 @node Acknowledgments
41927 @chapter Acknowledgments
41929 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
41930 which was designed and
41931 implemented by Eelco Dolstra, with contributions from other people (see
41932 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
41933 management, and promoted unprecedented features, such as transactional
41934 package upgrades and rollbacks, per-user profiles, and referentially
41935 transparent build processes. Without this work, Guix would not exist.
41937 The Nix-based software distributions, Nixpkgs and NixOS, have also been
41938 an inspiration for Guix.
41940 GNU@tie{}Guix itself is a collective work with contributions from a
41941 number of people. See the @file{AUTHORS} file in Guix for more
41942 information on these fine people. The @file{THANKS} file lists people
41943 who have helped by reporting bugs, taking care of the infrastructure,
41944 providing artwork and themes, making suggestions, and more---thank you!
41947 @c *********************************************************************
41948 @node GNU Free Documentation License
41949 @appendix GNU Free Documentation License
41950 @cindex license, GNU Free Documentation License
41951 @include fdl-1.3.texi
41953 @c *********************************************************************
41954 @node Concept Index
41955 @unnumbered Concept Index
41958 @node Programming Index
41959 @unnumbered Programming Index
41960 @syncodeindex tp fn
41961 @syncodeindex vr fn
41966 @c Local Variables:
41967 @c ispell-local-dictionary: "american";