6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
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25 Copyright @copyright{} 2012-2022 Ludovic Courtès@*
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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 playform 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 Once a package definition is in place, the
7326 package may actually be built using the @code{guix build} command-line
7327 tool (@pxref{Invoking guix build}), troubleshooting any build failures
7328 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
7329 package definition using the @command{guix edit} command
7330 (@pxref{Invoking guix edit}).
7331 @xref{Packaging Guidelines}, for
7332 more information on how to test package definitions, and
7333 @ref{Invoking guix lint}, for information on how to check a definition
7334 for style conformance.
7335 @vindex GUIX_PACKAGE_PATH
7336 Lastly, @pxref{Channels}, for information
7337 on how to extend the distribution by adding your own package definitions
7340 Finally, updating the package definition to a new upstream version
7341 can be partly automated by the @command{guix refresh} command
7342 (@pxref{Invoking guix refresh}).
7344 Behind the scenes, a derivation corresponding to the @code{<package>}
7345 object is first computed by the @code{package-derivation} procedure.
7346 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
7347 The build actions it prescribes may then be realized by using the
7348 @code{build-derivations} procedure (@pxref{The Store}).
7350 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
7351 Return the @code{<derivation>} object of @var{package} for @var{system}
7352 (@pxref{Derivations}).
7354 @var{package} must be a valid @code{<package>} object, and @var{system}
7355 must be a string denoting the target system type---e.g.,
7356 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
7357 must be a connection to the daemon, which operates on the store
7358 (@pxref{The Store}).
7362 @cindex cross-compilation
7363 Similarly, it is possible to compute a derivation that cross-builds a
7364 package for some other system:
7366 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
7367 @var{package} @var{target} [@var{system}]
7368 Return the @code{<derivation>} object of @var{package} cross-built from
7369 @var{system} to @var{target}.
7371 @var{target} must be a valid GNU triplet denoting the target hardware
7372 and operating system, such as @code{"aarch64-linux-gnu"}
7373 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
7376 Once you have package definitions, you can easily define @emph{variants}
7377 of those packages. @xref{Defining Package Variants}, for more on that.
7380 * package Reference:: The package data type.
7381 * origin Reference:: The origin data type.
7385 @node package Reference
7386 @subsection @code{package} Reference
7388 This section summarizes all the options available in @code{package}
7389 declarations (@pxref{Defining Packages}).
7391 @deftp {Data Type} package
7392 This is the data type representing a package recipe.
7396 The name of the package, as a string.
7398 @item @code{version}
7399 The version of the package, as a string. @xref{Version Numbers}, for
7403 An object telling how the source code for the package should be
7404 acquired. Most of the time, this is an @code{origin} object, which
7405 denotes a file fetched from the Internet (@pxref{origin Reference}). It
7406 can also be any other ``file-like'' object such as a @code{local-file},
7407 which denotes a file from the local file system (@pxref{G-Expressions,
7408 @code{local-file}}).
7410 @item @code{build-system}
7411 The build system that should be used to build the package (@pxref{Build
7414 @item @code{arguments} (default: @code{'()})
7415 The arguments that should be passed to the build system (@pxref{Build
7416 Systems}). This is a list, typically containing sequential
7417 keyword-value pairs, as in this example:
7422 ;; several fields omitted
7424 (list #:tests? #f ;skip tests
7425 #:make-flags #~'("VERBOSE=1") ;pass flags to 'make'
7426 #:configure-flags #~'("--enable-frobbing"))))
7429 The exact set of supported keywords depends on the build system
7430 (@pxref{Build Systems}), but you will find that almost all of them honor
7431 @code{#:configure-flags}, @code{#:make-flags}, @code{#:tests?}, and
7432 @code{#:phases}. The @code{#:phases} keyword in particular lets you
7433 modify the set of build phases for your package (@pxref{Build Phases}).
7435 @item @code{inputs} (default: @code{'()})
7436 @itemx @code{native-inputs} (default: @code{'()})
7437 @itemx @code{propagated-inputs} (default: @code{'()})
7438 @cindex inputs, of packages
7439 These fields list dependencies of the package. Each element of these
7440 lists is either a package, origin, or other ``file-like object''
7441 (@pxref{G-Expressions}); to specify the output of that file-like object
7442 that should be used, pass a two-element list where the second element is
7443 the output (@pxref{Packages with Multiple Outputs}, for more on package
7444 outputs). For example, the list below specifies three inputs:
7447 (list libffi libunistring
7448 `(,glib "bin")) ;the "bin" output of GLib
7451 In the example above, the @code{"out"} output of @code{libffi} and
7452 @code{libunistring} is used.
7454 @quotation Compatibility Note
7455 Until version 1.3.0, input lists were a list of tuples,
7456 where each tuple has a label for the input (a string) as its
7457 first element, a package, origin, or derivation as its second element,
7458 and optionally the name of the output thereof that should be used, which
7459 defaults to @code{"out"}. For example, the list below is equivalent to
7460 the one above, but using the @dfn{old input style}:
7463 ;; Old input style (deprecated).
7464 `(("libffi" ,libffi)
7465 ("libunistring" ,libunistring)
7466 ("glib:bin" ,glib "bin")) ;the "bin" output of GLib
7469 This style is now deprecated; it is still supported but support will be
7470 removed in a future version. It should not be used for new package
7471 definitions. @xref{Invoking guix style}, on how to migrate to the new
7475 @cindex cross compilation, package dependencies
7476 The distinction between @code{native-inputs} and @code{inputs} is
7477 necessary when considering cross-compilation. When cross-compiling,
7478 dependencies listed in @code{inputs} are built for the @emph{target}
7479 architecture; conversely, dependencies listed in @code{native-inputs}
7480 are built for the architecture of the @emph{build} machine.
7482 @code{native-inputs} is typically used to list tools needed at
7483 build time, but not at run time, such as Autoconf, Automake, pkg-config,
7484 Gettext, or Bison. @command{guix lint} can report likely mistakes in
7485 this area (@pxref{Invoking guix lint}).
7487 @anchor{package-propagated-inputs}
7488 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
7489 specified packages will be automatically installed to profiles
7490 (@pxref{Features, the role of profiles in Guix}) alongside the package
7491 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
7492 package}}, for information on how @command{guix package} deals with
7495 For example this is necessary when packaging a C/C++ library that needs
7496 headers of another library to compile, or when a pkg-config file refers
7497 to another one @i{via} its @code{Requires} field.
7499 Another example where @code{propagated-inputs} is useful is for languages
7500 that lack a facility to record the run-time search path akin to the
7501 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
7502 more. When packaging libraries written in those languages, ensure they
7503 can find library code they depend on at run time by listing run-time
7504 dependencies in @code{propagated-inputs} rather than @code{inputs}.
7506 @item @code{outputs} (default: @code{'("out")})
7507 The list of output names of the package. @xref{Packages with Multiple
7508 Outputs}, for typical uses of additional outputs.
7510 @item @code{native-search-paths} (default: @code{'()})
7511 @itemx @code{search-paths} (default: @code{'()})
7512 A list of @code{search-path-specification} objects describing
7513 search-path environment variables honored by the package. @xref{Search
7514 Paths}, for more on search path specifications.
7516 As for inputs, the distinction between @code{native-search-paths} and
7517 @code{search-paths} only matters when cross-compiling. In a
7518 cross-compilation context, @code{native-search-paths} applies
7519 exclusively to native inputs whereas @code{search-paths} applies only to
7522 Packages such as cross-compilers care about target inputs---for
7523 instance, our (modified) GCC cross-compiler has
7524 @env{CROSS_C_INCLUDE_PATH} in @code{search-paths}, which allows it to
7525 pick @file{.h} files for the target system and @emph{not} those of
7526 native inputs. For the majority of packages though, only
7527 @code{native-search-paths} makes sense.
7529 @item @code{replacement} (default: @code{#f})
7530 This must be either @code{#f} or a package object that will be used as a
7531 @dfn{replacement} for this package. @xref{Security Updates, grafts},
7534 @item @code{synopsis}
7535 A one-line description of the package.
7537 @item @code{description}
7538 A more elaborate description of the package, as a string in Texinfo
7541 @item @code{license}
7542 @cindex license, of packages
7543 The license of the package; a value from @code{(guix licenses)},
7544 or a list of such values.
7546 @item @code{home-page}
7547 The URL to the home-page of the package, as a string.
7549 @item @code{supported-systems} (default: @code{%supported-systems})
7550 The list of systems supported by the package, as strings of the form
7551 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
7553 @item @code{location} (default: source location of the @code{package} form)
7554 The source location of the package. It is useful to override this when
7555 inheriting from another package, in which case this field is not
7556 automatically corrected.
7560 @deffn {Scheme Syntax} this-package
7561 When used in the @emph{lexical scope} of a package field definition, this
7562 identifier resolves to the package being defined.
7564 The example below shows how to add a package as a native input of itself when
7572 ;; When cross-compiled, Guile, for example, depends on
7573 ;; a native version of itself. Add it here.
7574 (native-inputs (if (%current-target-system)
7579 It is an error to refer to @code{this-package} outside a package definition.
7582 The following helper procedures are provided to help deal with package
7585 @deffn {Scheme Procedure} lookup-package-input @var{package} @var{name}
7586 @deffnx {Scheme Procedure} lookup-package-native-input @var{package} @var{name}
7587 @deffnx {Scheme Procedure} lookup-package-propagated-input @var{package} @var{name}
7588 @deffnx {Scheme Procedure} lookup-package-direct-input @var{package} @var{name}
7589 Look up @var{name} among @var{package}'s inputs (or native, propagated,
7590 or direct inputs). Return it if found, @code{#f} otherwise.
7592 @var{name} is the name of a package depended on. Here's how you might
7596 (use-modules (guix packages) (gnu packages base))
7598 (lookup-package-direct-input coreutils "gmp")
7599 @result{} #<package gmp@@6.2.1 @dots{}>
7602 In this example we obtain the @code{gmp} package that is among the
7603 direct inputs of @code{coreutils}.
7606 @cindex development inputs, of a package
7607 @cindex implicit inputs, of a package
7608 Sometimes you will want to obtain the list of inputs needed to
7609 @emph{develop} a package---all the inputs that are visible when the
7610 package is compiled. This is what the @code{package-development-inputs}
7613 @deffn {Scheme Procedure} package-development-inputs @var{package} @
7614 [@var{system}] [#:target #f]
7615 Return the list of inputs required by @var{package} for development
7616 purposes on @var{system}. When @var{target} is true, return the inputs
7617 needed to cross-compile @var{package} from @var{system} to
7618 @var{triplet}, where @var{triplet} is a triplet such as
7619 @code{"aarch64-linux-gnu"}.
7621 Note that the result includes both explicit inputs and implicit
7622 inputs---inputs automatically added by the build system (@pxref{Build
7623 Systems}). Let us take the @code{hello} package to illustrate that:
7626 (use-modules (gnu packages base) (guix packages))
7629 @result{} #<package hello@@2.10 gnu/packages/base.scm:79 7f585d4f6790>
7631 (package-direct-inputs hello)
7634 (package-development-inputs hello)
7635 @result{} (("source" @dots{}) ("tar" #<package tar@@1.32 @dots{}>) @dots{})
7638 In this example, @code{package-direct-inputs} returns the empty list,
7639 because @code{hello} has zero explicit dependencies. Conversely,
7640 @code{package-development-inputs} includes inputs implicitly added by
7641 @code{gnu-build-system} that are required to build @code{hello}: tar,
7642 gzip, GCC, libc, Bash, and more. To visualize it, @command{guix graph
7643 hello} would show you explicit inputs, whereas @command{guix graph -t
7644 bag hello} would include implicit inputs (@pxref{Invoking guix graph}).
7647 Because packages are regular Scheme objects that capture a complete
7648 dependency graph and associated build procedures, it is often useful to
7649 write procedures that take a package and return a modified version
7650 thereof according to some parameters. Below are a few examples.
7652 @cindex tool chain, choosing a package's tool chain
7653 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
7654 Return a variant of @var{package} that uses @var{toolchain} instead of
7655 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
7656 inputs (label/package tuples) providing equivalent functionality, such
7657 as the @code{gcc-toolchain} package.
7659 The example below returns a variant of the @code{hello} package built
7660 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
7661 GNU C Library) instead of the default tool chain:
7664 (let ((toolchain (specification->package "gcc-toolchain@@10")))
7665 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
7668 The build tool chain is part of the @dfn{implicit inputs} of
7669 packages---it's usually not listed as part of the various ``inputs''
7670 fields and is instead pulled in by the build system. Consequently, this
7671 procedure works by changing the build system of @var{package} so that it
7672 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
7673 for more on build systems.
7676 @node origin Reference
7677 @subsection @code{origin} Reference
7679 This section documents @dfn{origins}. An @code{origin} declaration
7680 specifies data that must be ``produced''---downloaded, usually---and
7681 whose content hash is known in advance. Origins are primarily used to
7682 represent the source code of packages (@pxref{Defining Packages}). For
7683 that reason, the @code{origin} form allows you to declare patches to
7684 apply to the original source code as well as code snippets to modify it.
7686 @deftp {Data Type} origin
7687 This is the data type representing a source code origin.
7691 An object containing the URI of the source. The object type depends on
7692 the @code{method} (see below). For example, when using the
7693 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
7694 values are: a URL represented as a string, or a list thereof.
7696 @cindex fixed-output derivations, for download
7698 A monadic procedure that handles the given URI@. The procedure must
7699 accept at least three arguments: the value of the @code{uri} field and
7700 the hash algorithm and hash value specified by the @code{hash} field.
7701 It must return a store item or a derivation in the store monad
7702 (@pxref{The Store Monad}); most methods return a fixed-output derivation
7703 (@pxref{Derivations}).
7705 Commonly used methods include @code{url-fetch}, which fetches data from
7706 a URL, and @code{git-fetch}, which fetches data from a Git repository
7710 A bytevector containing the SHA-256 hash of the source. This is
7711 equivalent to providing a @code{content-hash} SHA256 object in the
7712 @code{hash} field described below.
7715 The @code{content-hash} object of the source---see below for how to use
7716 @code{content-hash}.
7718 You can obtain this information using @code{guix download}
7719 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
7722 @item @code{file-name} (default: @code{#f})
7723 The file name under which the source code should be saved. When this is
7724 @code{#f}, a sensible default value will be used in most cases. In case
7725 the source is fetched from a URL, the file name from the URL will be
7726 used. For version control checkouts, it is recommended to provide the
7727 file name explicitly because the default is not very descriptive.
7729 @item @code{patches} (default: @code{'()})
7730 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
7731 file-like objects}) pointing to patches to be applied to the source.
7733 This list of patches must be unconditional. In particular, it cannot
7734 depend on the value of @code{%current-system} or
7735 @code{%current-target-system}.
7737 @item @code{snippet} (default: @code{#f})
7738 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
7739 in the source directory. This is a convenient way to modify the source,
7740 sometimes more convenient than a patch.
7742 @item @code{patch-flags} (default: @code{'("-p1")})
7743 A list of command-line flags that should be passed to the @code{patch}
7746 @item @code{patch-inputs} (default: @code{#f})
7747 Input packages or derivations to the patching process. When this is
7748 @code{#f}, the usual set of inputs necessary for patching are provided,
7749 such as GNU@tie{}Patch.
7751 @item @code{modules} (default: @code{'()})
7752 A list of Guile modules that should be loaded during the patching
7753 process and while running the code in the @code{snippet} field.
7755 @item @code{patch-guile} (default: @code{#f})
7756 The Guile package that should be used in the patching process. When
7757 this is @code{#f}, a sensible default is used.
7761 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
7762 Construct a content hash object for the given @var{algorithm}, and with
7763 @var{value} as its hash value. When @var{algorithm} is omitted, assume
7764 it is @code{sha256}.
7766 @var{value} can be a literal string, in which case it is base32-decoded,
7767 or it can be a bytevector.
7769 The following forms are all equivalent:
7772 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
7773 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
7775 (content-hash (base32
7776 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
7777 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
7781 Technically, @code{content-hash} is currently implemented as a macro.
7782 It performs sanity checks at macro-expansion time, when possible, such
7783 as ensuring that @var{value} has the right size for @var{algorithm}.
7786 As we have seen above, how exactly the data an origin refers to is
7787 retrieved is determined by its @code{method} field. The @code{(guix
7788 download)} module provides the most common method, @code{url-fetch},
7791 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
7792 [name] [#:executable? #f]
7793 Return a fixed-output derivation that fetches data from @var{url} (a
7794 string, or a list of strings denoting alternate URLs), which is expected
7795 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
7796 the file name is the base name of URL; optionally, @var{name} can
7797 specify a different file name. When @var{executable?} is true, make the
7798 downloaded file executable.
7800 When one of the URL starts with @code{mirror://}, then its host part is
7801 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
7803 Alternatively, when URL starts with @code{file://}, return the
7804 corresponding file name in the store.
7807 Likewise, the @code{(guix git-download)} module defines the
7808 @code{git-fetch} origin method, which fetches data from a Git version
7809 control repository, and the @code{git-reference} data type to describe
7810 the repository and revision to fetch.
7812 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
7813 Return a fixed-output derivation that fetches @var{ref}, a
7814 @code{<git-reference>} object. The output is expected to have recursive
7815 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7816 the file name, or a generic name if @code{#f}.
7819 @deftp {Data Type} git-reference
7820 This data type represents a Git reference for @code{git-fetch} to
7825 The URL of the Git repository to clone.
7828 This string denotes either the commit to fetch (a hexadecimal string),
7829 or the tag to fetch. You can also use a ``short'' commit ID or a
7830 @command{git describe} style identifier such as
7831 @code{v1.0.1-10-g58d7909c97}.
7833 @item @code{recursive?} (default: @code{#f})
7834 This Boolean indicates whether to recursively fetch Git sub-modules.
7837 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
7842 (url "https://git.savannah.gnu.org/git/hello.git")
7846 This is equivalent to the reference below, which explicitly names the
7851 (url "https://git.savannah.gnu.org/git/hello.git")
7852 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
7856 For Mercurial repositories, the module @code{(guix hg-download)} defines
7857 the @code{hg-fetch} origin method and @code{hg-reference} data type for
7858 support of the Mercurial version control system.
7860 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
7862 Return a fixed-output derivation that fetches @var{ref}, a
7863 @code{<hg-reference>} object. The output is expected to have recursive
7864 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7865 the file name, or a generic name if @code{#false}.
7868 @node Defining Package Variants
7869 @section Defining Package Variants
7871 @cindex customizing packages
7872 @cindex variants, of packages
7873 One of the nice things with Guix is that, given a package definition,
7874 you can easily @emph{derive} variants of that package---for a different
7875 upstream version, with different dependencies, different compilation
7876 options, and so on. Some of these custom packages can be defined
7877 straight from the command line (@pxref{Package Transformation Options}).
7878 This section describes how to define package variants in code. This can
7879 be useful in ``manifests'' (@pxref{profile-manifest,
7880 @option{--manifest}}) and in your own package collection
7881 (@pxref{Creating a Channel}), among others!
7883 @cindex inherit, for package definitions
7884 As discussed earlier, packages are first-class objects in the Scheme
7885 language. The @code{(guix packages)} module provides the @code{package}
7886 construct to define new package objects (@pxref{package Reference}).
7887 The easiest way to define a package variant is using the @code{inherit}
7888 keyword together with @code{package}. This allows you to inherit from a
7889 package definition while overriding the fields you want.
7891 For example, given the @code{hello} variable, which contains a
7892 definition for the current version of GNU@tie{}Hello, here's how you
7893 would define a variant for version 2.2 (released in 2006, it's
7897 (use-modules (gnu packages base)) ;for 'hello'
7905 (uri (string-append "mirror://gnu/hello/hello-" version
7909 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
7912 The example above corresponds to what the @option{--with-source} package
7913 transformation option does. Essentially @code{hello-2.2} preserves all
7914 the fields of @code{hello}, except @code{version} and @code{source},
7915 which it overrides. Note that the original @code{hello} variable is
7916 still there, in the @code{(gnu packages base)} module, unchanged. When
7917 you define a custom package like this, you are really @emph{adding} a
7918 new package definition; the original one remains available.
7920 You can just as well define variants with a different set of
7921 dependencies than the original package. For example, the default
7922 @code{gdb} package depends on @code{guile}, but since that is an
7923 optional dependency, you can define a variant that removes that
7927 (use-modules (gnu packages gdb)) ;for 'gdb'
7929 (define gdb-sans-guile
7932 (inputs (modify-inputs (package-inputs gdb)
7933 (delete "guile")))))
7936 The @code{modify-inputs} form above removes the @code{"guile"} package
7937 from the @code{inputs} field of @code{gdb}. The @code{modify-inputs}
7938 macro is a helper that can prove useful anytime you want to remove, add,
7939 or replace package inputs.
7941 @deffn {Scheme Syntax} modify-inputs @var{inputs} @var{clauses}
7942 Modify the given package inputs, as returned by @code{package-inputs} & co.,
7943 according to the given clauses. Each clause must have one of the
7947 @item (delete @var{name}@dots{})
7948 Delete from the inputs packages with the given @var{name}s (strings).
7950 @item (append @var{package}@dots{})
7951 Add @var{package}s to the end of the input list.
7953 @item (prepend @var{package}@dots{})
7954 Add @var{package}s to the front of the input list.
7957 The example below removes the GMP and ACL inputs of Coreutils and adds
7958 libcap to the back of the input list:
7961 (modify-inputs (package-inputs coreutils)
7962 (delete "gmp" "acl")
7966 The example below replaces the @code{guile} package from the inputs of
7967 @code{guile-redis} with @code{guile-2.2}:
7970 (modify-inputs (package-inputs guile-redis)
7971 (replace "guile" guile-2.2))
7974 The last type of clause is @code{prepend}, to add inputs to the front of
7978 In some cases, you may find it useful to write functions
7979 (``procedures'', in Scheme parlance) that return a package based on some
7980 parameters. For example, consider the @code{luasocket} library for the
7981 Lua programming language. We want to create @code{luasocket} packages
7982 for major versions of Lua. One way to do that is to define a procedure
7983 that takes a Lua package and returns a @code{luasocket} package that
7987 (define (make-lua-socket name lua)
7988 ;; Return a luasocket package built with LUA.
7992 ;; several fields omitted
7994 (synopsis "Socket library for Lua")))
7996 (define-public lua5.1-socket
7997 (make-lua-socket "lua5.1-socket" lua-5.1))
7999 (define-public lua5.2-socket
8000 (make-lua-socket "lua5.2-socket" lua-5.2))
8003 Here we have defined packages @code{lua5.1-socket} and
8004 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
8005 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
8006 more info on procedures. Having top-level public definitions for these
8007 two packages means that they can be referred to from the command line
8008 (@pxref{Package Modules}).
8010 @cindex package transformations
8011 These are pretty simple package variants. As a convenience, the
8012 @code{(guix transformations)} module provides a high-level interface
8013 that directly maps to the more sophisticated package transformation
8014 options (@pxref{Package Transformation Options}):
8016 @deffn {Scheme Procedure} options->transformation @var{opts}
8017 Return a procedure that, when passed an object to build (package,
8018 derivation, etc.), applies the transformations specified by @var{opts} and returns
8019 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
8022 ((with-branch . "guile-gcrypt=master")
8023 (without-tests . "libgcrypt"))
8026 Each symbol names a transformation and the corresponding string is an argument
8027 to that transformation.
8030 For instance, a manifest equivalent to this command:
8034 --with-branch=guile-gcrypt=master \
8035 --with-debug-info=zlib
8039 ... would look like this:
8042 (use-modules (guix transformations))
8045 ;; The package transformation procedure.
8046 (options->transformation
8047 '((with-branch . "guile-gcrypt=master")
8048 (with-debug-info . "zlib"))))
8051 (list (transform (specification->package "guix"))))
8054 @cindex input rewriting
8055 @cindex dependency graph rewriting
8056 The @code{options->transformation} procedure is convenient, but it's
8057 perhaps also not as flexible as you may like. How is it implemented?
8058 The astute reader probably noticed that most package transformation
8059 options go beyond the superficial changes shown in the first examples of
8060 this section: they involve @dfn{input rewriting}, whereby the dependency
8061 graph of a package is rewritten by replacing specific inputs by others.
8063 Dependency graph rewriting, for the purposes of swapping packages in the
8064 graph, is what the @code{package-input-rewriting} procedure in
8065 @code{(guix packages)} implements.
8067 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
8068 [@var{rewrite-name}] [#:deep? #t]
8069 Return a procedure that, when passed a package, replaces its direct and
8070 indirect dependencies, including implicit inputs when @var{deep?} is
8071 true, according to @var{replacements}. @var{replacements} is a list of
8072 package pairs; the first element of each pair is the package to replace,
8073 and the second one is the replacement.
8075 Optionally, @var{rewrite-name} is a one-argument procedure that takes
8076 the name of a package and returns its new name after rewrite.
8080 Consider this example:
8083 (define libressl-instead-of-openssl
8084 ;; This is a procedure to replace OPENSSL by LIBRESSL,
8086 (package-input-rewriting `((,openssl . ,libressl))))
8088 (define git-with-libressl
8089 (libressl-instead-of-openssl git))
8093 Here we first define a rewriting procedure that replaces @var{openssl}
8094 with @var{libressl}. Then we use it to define a @dfn{variant} of the
8095 @var{git} package that uses @var{libressl} instead of @var{openssl}.
8096 This is exactly what the @option{--with-input} command-line option does
8097 (@pxref{Package Transformation Options, @option{--with-input}}).
8099 The following variant of @code{package-input-rewriting} can match packages to
8100 be replaced by name rather than by identity.
8102 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
8103 Return a procedure that, given a package, applies the given
8104 @var{replacements} to all the package graph, including implicit inputs
8105 unless @var{deep?} is false. @var{replacements} is a list of
8106 spec/procedures pair; each spec is a package specification such as
8107 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
8108 package and returns a replacement for that package.
8111 The example above could be rewritten this way:
8114 (define libressl-instead-of-openssl
8115 ;; Replace all the packages called "openssl" with LibreSSL.
8116 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
8119 The key difference here is that, this time, packages are matched by spec and
8120 not by identity. In other words, any package in the graph that is called
8121 @code{openssl} will be replaced.
8123 A more generic procedure to rewrite a package dependency graph is
8124 @code{package-mapping}: it supports arbitrary changes to nodes in the
8127 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
8128 Return a procedure that, given a package, applies @var{proc} to all the packages
8129 depended on and returns the resulting package. The procedure stops recursion
8130 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
8131 applied to implicit inputs as well.
8134 @node Writing Manifests
8135 @section Writing Manifests
8138 @cindex bill of materials (manifests)
8139 @command{guix} commands let you specify package lists on the command
8140 line. This is convenient, but as the command line becomes longer and
8141 less trivial, it quickly becomes more convenient to have that package
8142 list in what we call a @dfn{manifest}. A manifest is some sort of a
8143 ``bill of materials'' that defines a package set. You would typically
8144 come up with a code snippet that builds the manifest, store it in a
8145 file, say @file{manifest.scm}, and then pass that file to the
8146 @option{-m} (or @option{--manifest}) option that many @command{guix}
8147 commands support. For example, here's what a manifest for a simple
8148 package set might look like:
8151 ;; Manifest for three packages.
8152 (specifications->manifest '("gcc-toolchain" "make" "git"))
8155 Once you have that manifest, you can pass it, for example, to
8156 @command{guix package} to install just those three packages to your
8157 profile (@pxref{profile-manifest, @option{-m} option of @command{guix
8161 guix package -m manifest.scm
8165 ... or you can pass it to @command{guix shell} (@pxref{shell-manifest,
8166 @command{-m} option of @command{guix shell}}) to spawn an ephemeral
8170 guix shell -m manifest.scm
8174 ... or you can pass it to @command{guix pack} in pretty much the same
8175 way (@pxref{pack-manifest, @option{-m} option of @command{guix pack}}).
8176 You can store the manifest under version control, share it with others
8177 so they can easily get set up, etc.
8179 But how do you write your first manifest? To get started, maybe you'll
8180 want to write a manifest that mirrors what you already have in a
8181 profile. Rather than start from a blank page, @command{guix package}
8182 can generate a manifest for you (@pxref{export-manifest, @command{guix
8183 package --export-manifest}}):
8186 # Write to 'manifest.scm' a manifest corresponding to the
8187 # default profile, ~/.guix-profile.
8188 guix package --export-manifest > manifest.scm
8191 Or maybe you'll want to ``translate'' command-line arguments into a
8192 manifest. In that case, @command{guix shell} can help
8193 (@pxref{shell-export-manifest, @command{guix shell --export-manifest}}):
8196 # Write a manifest for the packages specified on the command line.
8197 guix shell --export-manifest gcc-toolchain make git > manifest.scm
8200 In both cases, the @option{--export-manifest} option tries hard to
8201 generate a faithful manifest; in particular, it takes package
8202 transformation options into account (@pxref{Package Transformation
8206 Manifests are @emph{symbolic}: they refer to packages of the channels
8207 @emph{currently in use} (@pxref{Channels}). In the example above,
8208 @code{gcc-toolchain} might refer to version 11 today, but it might refer
8209 to version 13 two years from now.
8211 If you want to ``pin'' your software environment to specific package
8212 versions and variants, you need an additional piece of information: the
8213 list of channel revisions in use, as returned by @command{guix
8214 describe}. @xref{Replicating Guix}, for more information.
8217 Once you've obtained your first manifest, perhaps you'll want to
8218 customize it. Since your manifest is code, you now have access to all
8219 the Guix programming interfaces!
8221 Let's assume you want a manifest to deploy a custom variant of GDB, the
8222 GNU Debugger, that does not depend on Guile, together with another
8223 package. Building on the example seen in the previous section
8224 (@pxref{Defining Package Variants}), you can write a manifest along
8228 (use-modules (guix packages)
8229 (gnu packages gdb) ;for 'gdb'
8230 (gnu packages version-control)) ;for 'git'
8232 ;; Define a variant of GDB without a dependency on Guile.
8233 (define gdb-sans-guile
8236 (inputs (modify-inputs (package-inputs gdb)
8237 (delete "guile")))))
8239 ;; Return a manifest containing that one package plus Git.
8240 (packages->manifest (list gdb-sans-guile git))
8243 Note that in this example, the manifest directly refers to the
8244 @code{gdb} and @code{git} variables, which are bound to a @code{package}
8245 object (@pxref{package Reference}), instead of calling
8246 @code{specifications->manifest} to look up packages by name as we did
8247 before. The @code{use-modules} form at the top lets us access the core
8248 package interface (@pxref{Defining Packages}) and the modules that
8249 define @code{gdb} and @code{git} (@pxref{Package Modules}). Seamlessly,
8250 we're weaving all this together---the possibilities are endless, unleash
8253 The data type for manifests as well as supporting procedures are defined
8254 in the @code{(guix profiles)} module, which is automatically available
8255 to code passed to @option{-m}. The reference follows.
8257 @deftp {Data Type} manifest
8258 Data type representing a manifest.
8260 It currently has one field:
8264 This must be a list of @code{manifest-entry} records---see below.
8268 @deftp {Data Type} manifest-entry
8269 Data type representing a manifest entry. A manifest entry contains
8270 essential metadata: a name and version string, the object (usually a
8271 package) for that entry, the desired output (@pxref{Packages with
8272 Multiple Outputs}), and a number of optional pieces of information
8275 Most of the time, you won't build a manifest entry directly; instead,
8276 you will pass a package to @code{package->manifest-entry}, described
8277 below. In some unusual cases though, you might want to create manifest
8278 entries for things that are @emph{not} packages, as in this example:
8281 ;; Manually build a single manifest entry for a non-package object.
8282 (let ((hello (program-file "hello" #~(display "Hi!"))))
8287 (computed-file "hello-directory"
8288 #~(let ((bin (string-append #$output "/bin")))
8289 (mkdir #$output) (mkdir bin)
8291 (string-append bin "/hello")))))))
8294 The available fields are the following:
8298 @itemx @code{version}
8299 Name and version string for this entry.
8302 A package or other file-like object (@pxref{G-Expressions, file-like
8305 @item @code{output} (default: @code{"out"})
8306 Output of @code{item} to use, in case @code{item} has multiple outputs
8307 (@pxref{Packages with Multiple Outputs}).
8309 @item @code{dependencies} (default: @code{'()})
8310 List of manifest entries this entry depends on. When building a
8311 profile, dependencies are added to the profile.
8313 Typically, the propagated inputs of a package (@pxref{package Reference,
8314 @code{propagated-inputs}}) end up having a corresponding manifest entry
8315 in among the dependencies of the package's own manifest entry.
8317 @item @code{search-paths} (default: @code{'()})
8318 The list of search path specifications honored by this entry
8319 (@pxref{Search Paths}).
8321 @item @code{properties} (default: @code{'()})
8322 List of symbol/value pairs. When building a profile, those properties
8325 This can be used to piggyback additional metadata---e.g., the
8326 transformations applied to a package (@pxref{Package Transformation
8329 @item @code{parent} (default: @code{(delay #f)})
8330 A promise pointing to the ``parent'' manifest entry.
8332 This is used as a hint to provide context when reporting an error
8333 related to a manifest entry coming from a @code{dependencies} field.
8337 @deffn {Scheme Procedure} concatenate-manifests @var{lst}
8338 Concatenate the manifests listed in @var{lst} and return the resulting
8342 @c TODO: <manifest-pattern>, manifest-lookup, manifest-remove, etc.
8344 @deffn {Scheme Procedure} package->manifest-entry @var{package} @
8345 [@var{output}] [#:properties]
8346 Return a manifest entry for the @var{output} of package @var{package},
8347 where @var{output} defaults to @code{"out"}, and with the given
8348 @var{properties}. By default @var{properties} is the empty list or, if
8349 one or more package transformations were applied to @var{package}, it is
8350 an association list representing those transformations, suitable as an
8351 argument to @code{options->transformation} (@pxref{Defining Package
8352 Variants, @code{options->transformation}}).
8354 The code snippet below builds a manifest with an entry for the default
8355 output and the @code{send-email} output of the @code{git} package:
8358 (use-modules (gnu packages version-control))
8360 (manifest (list (package->manifest-entry git)
8361 (package->manifest-entry git "send-email")))
8365 @deffn {Scheme Procedure} packages->manifest @var{packages}
8366 Return a list of manifest entries, one for each item listed in
8367 @var{packages}. Elements of @var{packages} can be either package
8368 objects or package/string tuples denoting a specific output of a
8371 Using this procedure, the manifest above may be rewritten more
8375 (use-modules (gnu packages version-control))
8377 (packages->manifest (list git `(,git "send-email")))
8381 @anchor{package-development-manifest}
8382 @deffn {Scheme Procedure} package->development-manifest @var{package} @
8383 [@var{system}] [#:target]
8384 Return a manifest for the @dfn{development inputs} of @var{package} for
8385 @var{system}, optionally when cross-compiling to @var{target}.
8386 Development inputs include both explicit and implicit inputs of
8389 Like the @option{-D} option of @command{guix shell}
8390 (@pxref{shell-development-option, @command{guix shell -D}}), the
8391 resulting manifest describes the environment in which one can develop
8392 @var{package}. For example, suppose you're willing to set up a
8393 development environment for Inkscape, with the addition of Git for
8394 version control; you can describe that ``bill of materials'' with the
8398 (use-modules (gnu packages inkscape) ;for 'inkscape'
8399 (gnu packages version-control)) ;for 'git'
8401 (concatenate-manifests
8402 (list (package->development-manifest inkscape)
8403 (packages->manifest (list git))))
8406 In this example, the development manifest that
8407 @code{package->development-manifest} returns includes the compiler
8408 (GCC), the many supporting libraries (Boost, GLib, GTK, etc.), and a
8409 couple of additional development tools---these are the dependencies
8410 @command{guix show inkscape} lists.
8413 @c TODO: Move (gnu packages) interface to a section of its own.
8415 Last, the @code{(gnu packages)} module provides higher-level facilities
8416 to build manifests. In particular, it lets you look up packages by
8419 @deffn {Scheme Procedure} specifications->manifest @var{specs}
8420 Given @var{specs}, a list of specifications such as @code{"emacs@@25.2"}
8421 or @code{"guile:debug"}, return a manifest. Specs have the format that
8422 command-line tools such as @command{guix install} and @command{guix
8423 package} understand (@pxref{Invoking guix package}).
8425 As an example, it lets you rewrite the Git manifest that we saw earlier
8429 (specifications->manifest '("git" "git:send-email"))
8432 Notice that we do not need to worry about @code{use-modules}, importing
8433 the right set of modules, and referring to the right variables.
8434 Instead, we directly refer to packages in the same way as on the command
8435 line, which can often be more convenient.
8438 @c TODO: specifications->package, etc.
8442 @section Build Systems
8444 @cindex build system
8445 Each package definition specifies a @dfn{build system} and arguments for
8446 that build system (@pxref{Defining Packages}). This @code{build-system}
8447 field represents the build procedure of the package, as well as implicit
8448 dependencies of that build procedure.
8450 Build systems are @code{<build-system>} objects. The interface to
8451 create and manipulate them is provided by the @code{(guix build-system)}
8452 module, and actual build systems are exported by specific modules.
8454 @cindex bag (low-level package representation)
8455 Under the hood, build systems first compile package objects to
8456 @dfn{bags}. A @dfn{bag} is like a package, but with less
8457 ornamentation---in other words, a bag is a lower-level representation of
8458 a package, which includes all the inputs of that package, including some
8459 that were implicitly added by the build system. This intermediate
8460 representation is then compiled to a derivation (@pxref{Derivations}).
8461 The @code{package-with-c-toolchain} is an example of a way to change the
8462 implicit inputs that a package's build system pulls in (@pxref{package
8463 Reference, @code{package-with-c-toolchain}}).
8465 Build systems accept an optional list of @dfn{arguments}. In package
8466 definitions, these are passed @i{via} the @code{arguments} field
8467 (@pxref{Defining Packages}). They are typically keyword arguments
8468 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
8469 Guile Reference Manual}). The value of these arguments is usually
8470 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
8471 by the daemon (@pxref{Derivations}).
8473 The main build system is @code{gnu-build-system}, which implements the
8474 standard build procedure for GNU and many other packages. It
8475 is provided by the @code{(guix build-system gnu)} module.
8477 @defvr {Scheme Variable} gnu-build-system
8478 @code{gnu-build-system} represents the GNU Build System, and variants
8479 thereof (@pxref{Configuration, configuration and makefile conventions,,
8480 standards, GNU Coding Standards}).
8482 @cindex build phases
8483 In a nutshell, packages using it are configured, built, and installed with
8484 the usual @code{./configure && make && make check && make install}
8485 command sequence. In practice, a few additional steps are often needed.
8486 All these steps are split up in separate @dfn{phases}.
8487 @xref{Build Phases}, for more info on build phases and ways to customize
8490 In addition, this build system ensures that the ``standard'' environment
8491 for GNU packages is available. This includes tools such as GCC, libc,
8492 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
8493 build-system gnu)} module for a complete list). We call these the
8494 @dfn{implicit inputs} of a package, because package definitions do not
8495 have to mention them.
8497 This build system supports a number of keyword arguments, which can be
8498 passed @i{via} the @code{arguments} field of a package. Here are some
8499 of the main parameters:
8503 This argument specifies build-side code that evaluates to an alist of
8504 build phases. @xref{Build Phases}, for more information.
8506 @item #:configure-flags
8507 This is a list of flags (strings) passed to the @command{configure}
8508 script. @xref{Defining Packages}, for an example.
8511 This list of strings contains flags passed as arguments to
8512 @command{make} invocations in the @code{build}, @code{check}, and
8513 @code{install} phases.
8515 @item #:out-of-source?
8516 This Boolean, @code{#f} by default, indicates whether to run builds in a
8517 build directory separate from the source tree.
8519 When it is true, the @code{configure} phase creates a separate build
8520 directory, changes to that directory, and runs the @code{configure}
8521 script from there. This is useful for packages that require it, such as
8525 This Boolean, @code{#t} by default, indicates whether the @code{check}
8526 phase should run the package's test suite.
8529 This string, @code{"check"} by default, gives the name of the makefile
8530 target used by the @code{check} phase.
8532 @item #:parallel-build?
8533 @itemx #:parallel-tests?
8534 These Boolean values specify whether to build, respectively run the test
8535 suite, in parallel, with the @code{-j} flag of @command{make}. When
8536 they are true, @code{make} is passed @code{-j@var{n}}, where @var{n} is
8537 the number specified as the @option{--cores} option of
8538 @command{guix-daemon} or that of the @command{guix} client command
8539 (@pxref{Common Build Options, @option{--cores}}).
8541 @cindex RUNPATH, validation
8542 @item #:validate-runpath?
8543 This Boolean, @code{#t} by default, determines whether to ``validate''
8544 the @code{RUNPATH} of ELF binaries (@code{.so} shared libraries as well
8545 as executables) previously installed by the @code{install} phase.
8546 @xref{phase-validate-runpath, the @code{validate-runpath} phase}, for
8549 @item #:substitutable?
8550 This Boolean, @code{#t} by default, tells whether the package outputs
8551 should be substitutable---i.e., whether users should be able to obtain
8552 substitutes for them instead of building locally (@pxref{Substitutes}).
8554 @item #:allowed-references
8555 @itemx #:disallowed-references
8556 When true, these arguments must be a list of dependencies that must not
8557 appear among the references of the build results. If, upon build
8558 completion, some of these references are retained, the build process
8561 This is useful to ensure that a package does not erroneously keep a
8562 reference to some of it build-time inputs, in cases where doing so
8563 would, for example, unnecessarily increase its size (@pxref{Invoking
8567 Most other build systems support these keyword arguments.
8570 Other @code{<build-system>} objects are defined to support other
8571 conventions and tools used by free software packages. They inherit most
8572 of @code{gnu-build-system}, and differ mainly in the set of inputs
8573 implicitly added to the build process, and in the list of phases
8574 executed. Some of these build systems are listed below.
8576 @defvr {Scheme Variable} ant-build-system
8577 This variable is exported by @code{(guix build-system ant)}. It
8578 implements the build procedure for Java packages that can be built with
8579 @url{https://ant.apache.org/, Ant build tool}.
8581 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
8582 provided by the @code{icedtea} package to the set of inputs. Different
8583 packages can be specified with the @code{#:ant} and @code{#:jdk}
8584 parameters, respectively.
8586 When the original package does not provide a suitable Ant build file,
8587 the parameter @code{#:jar-name} can be used to generate a minimal Ant
8588 build file @file{build.xml} with tasks to build the specified jar
8589 archive. In this case the parameter @code{#:source-dir} can be used to
8590 specify the source sub-directory, defaulting to ``src''.
8592 The @code{#:main-class} parameter can be used with the minimal ant
8593 buildfile to specify the main class of the resulting jar. This makes the
8594 jar file executable. The @code{#:test-include} parameter can be used to
8595 specify the list of junit tests to run. It defaults to
8596 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
8597 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
8598 because abstract classes cannot be run as tests.
8600 The parameter @code{#:build-target} can be used to specify the Ant task
8601 that should be run during the @code{build} phase. By default the
8602 ``jar'' task will be run.
8606 @defvr {Scheme Variable} android-ndk-build-system
8607 @cindex Android distribution
8608 @cindex Android NDK build system
8609 This variable is exported by @code{(guix build-system android-ndk)}. It
8610 implements a build procedure for Android NDK (native development kit)
8611 packages using a Guix-specific build process.
8613 The build system assumes that packages install their public interface
8614 (header) files to the subdirectory @file{include} of the @code{out} output and
8615 their libraries to the subdirectory @file{lib} the @code{out} output.
8617 It's also assumed that the union of all the dependencies of a package
8618 has no conflicting files.
8620 For the time being, cross-compilation is not supported - so right now
8621 the libraries and header files are assumed to be host tools.
8625 @defvr {Scheme Variable} asdf-build-system/source
8626 @defvrx {Scheme Variable} asdf-build-system/sbcl
8627 @defvrx {Scheme Variable} asdf-build-system/ecl
8629 These variables, exported by @code{(guix build-system asdf)}, implement
8630 build procedures for Common Lisp packages using
8631 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
8632 definition facility for Common Lisp programs and libraries.
8634 The @code{asdf-build-system/source} system installs the packages in
8635 source form, and can be loaded using any common lisp implementation, via
8636 ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
8637 systems in the format which a particular implementation understands.
8638 These build systems can also be used to produce executable programs, or
8639 lisp images which contain a set of packages pre-loaded.
8641 The build system uses naming conventions. For binary packages, the
8642 package name should be prefixed with the lisp implementation, such as
8643 @code{sbcl-} for @code{asdf-build-system/sbcl}.
8645 Additionally, the corresponding source package should be labeled using
8646 the same convention as python packages (see @ref{Python Modules}), using
8647 the @code{cl-} prefix.
8649 In order to create executable programs and images, the build-side
8650 procedures @code{build-program} and @code{build-image} can be used.
8651 They should be called in a build phase after the
8652 @code{create-asdf-configuration} phase, so that the system which was
8653 just built can be used within the resulting image. @code{build-program}
8654 requires a list of Common Lisp expressions to be passed as the
8655 @code{#:entry-program} argument.
8657 By default, all the @file{.asd} files present in the sources are read to
8658 find system definitions. The @code{#:asd-files} parameter can be used
8659 to specify the list of @file{.asd} files to read. Furthermore, if the
8660 package defines a system for its tests in a separate file, it will be
8661 loaded before the tests are run if it is specified by the
8662 @code{#:test-asd-file} parameter. If it is not set, the files
8663 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
8664 and @code{test.asd} will be tried if they exist.
8666 If for some reason the package must be named in a different way than the
8667 naming conventions suggest, or if several systems must be compiled, the
8668 @code{#:asd-systems} parameter can be used to specify the list of system
8673 @defvr {Scheme Variable} cargo-build-system
8674 @cindex Rust programming language
8675 @cindex Cargo (Rust build system)
8676 This variable is exported by @code{(guix build-system cargo)}. It
8677 supports builds of packages using Cargo, the build tool of the
8678 @uref{https://www.rust-lang.org, Rust programming language}.
8680 It adds @code{rustc} and @code{cargo} to the set of inputs.
8681 A different Rust package can be specified with the @code{#:rust} parameter.
8683 Regular cargo dependencies should be added to the package definition similarly
8684 to other packages; those needed only at build time to native-inputs, others to
8685 inputs. If you need to add source-only crates then you should add them to via
8686 the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
8687 spec can be a package or a source definition. Note that the spec must
8688 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
8689 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
8690 should be added to the package definition via the
8691 @code{#:cargo-development-inputs} parameter.
8693 In its @code{configure} phase, this build system will make any source inputs
8694 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
8695 parameters available to cargo. It will also remove an included
8696 @code{Cargo.lock} file to be recreated by @code{cargo} during the
8697 @code{build} phase. The @code{package} phase will run @code{cargo package}
8698 to create a source crate for future use. The @code{install} phase installs
8699 the binaries defined by the crate. Unless @code{install-source? #f} is
8700 defined it will also install a source crate repository of itself and unpacked
8701 sources, to ease in future hacking on rust packages.
8704 @defvr {Scheme Variable} chicken-build-system
8705 This variable is exported by @code{(guix build-system chicken)}. It
8706 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
8707 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
8708 gets compiled by a C compiler, in this case GCC.
8710 This build system adds @code{chicken} to the package inputs, as well as
8711 the packages of @code{gnu-build-system}.
8713 The build system can't (yet) deduce the egg's name automatically, so just like
8714 with @code{go-build-system} and its @code{#:import-path}, you should define
8715 @code{#:egg-name} in the package's @code{arguments} field.
8717 For example, if you are packaging the @code{srfi-1} egg:
8720 (arguments '(#:egg-name "srfi-1"))
8723 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
8724 because CHICKEN doesn't embed absolute references in compiled eggs.
8725 Test dependencies should go to @code{native-inputs}, as usual.
8728 @defvr {Scheme Variable} copy-build-system
8729 This variable is exported by @code{(guix build-system copy)}. It
8730 supports builds of simple packages that don't require much compiling,
8731 mostly just moving files around.
8733 It adds much of the @code{gnu-build-system} packages to the set of
8734 inputs. Because of this, the @code{copy-build-system} does not require
8735 all the boilerplate code often needed for the
8736 @code{trivial-build-system}.
8738 To further simplify the file installation process, an
8739 @code{#:install-plan} argument is exposed to let the packager specify
8740 which files go where. The install plan is a list of @code{(@var{source}
8741 @var{target} [@var{filters}])}. @var{filters} are optional.
8744 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
8746 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
8747 @item Otherwise install @var{source} as @var{target}.
8750 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
8751 the trailing slash of @var{target} is implied with the same meaning
8754 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
8755 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
8756 @code{#:exclude-regexp}, only select files are installed depending on
8757 the filters. Each filters is specified by a list of strings.
8759 @item With @code{#:include}, install all the files which the path suffix matches
8760 at least one of the elements in the given list.
8761 @item With @code{#:include-regexp}, install all the files which the
8762 subpaths match at least one of the regular expressions in the given
8764 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
8765 are the complement of their inclusion counterpart. Without @code{#:include} flags,
8766 install all files but those matching the exclusion filters.
8767 If both inclusions and exclusions are specified, the exclusions are done
8768 on top of the inclusions.
8771 In all cases, the paths relative to @var{source} are preserved within
8778 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
8779 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
8780 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
8781 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
8782 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
8783 @file{share/my-app/sub/file}.
8784 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
8785 @file{share/my-app/file}.
8790 @cindex Clojure (programming language)
8791 @cindex simple Clojure build system
8792 @defvr {Scheme Variable} clojure-build-system
8793 This variable is exported by @code{(guix build-system clojure)}. It implements
8794 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
8795 using plain old @code{compile} in Clojure. Cross-compilation is not supported
8798 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
8799 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
8800 @code{#:zip} parameters, respectively.
8802 A list of source directories, test directories and jar names can be specified
8803 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
8804 parameters, respectively. Compile directory and main class can be specified
8805 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
8806 Other parameters are documented below.
8808 This build system is an extension of @code{ant-build-system}, but with the
8809 following phases changed:
8814 This phase calls @code{compile} in Clojure to compile source files and runs
8815 @command{jar} to create jars from both source files and compiled files
8816 according to the include list and exclude list specified in
8817 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
8818 has priority over the include list. These lists consist of symbols
8819 representing Clojure libraries or the special keyword @code{#:all} representing
8820 all Clojure libraries found under the source directories. The parameter
8821 @code{#:omit-source?} decides if source should be included into the jars.
8824 This phase runs tests according to the include list and exclude list specified
8825 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
8826 meanings are analogous to that of @code{#:aot-include} and
8827 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
8828 stands for all Clojure libraries found under the test directories. The
8829 parameter @code{#:tests?} decides if tests should be run.
8832 This phase installs all jars built previously.
8835 Apart from the above, this build system also contains an additional phase:
8840 This phase installs all top-level files with base name matching
8841 @code{%doc-regex}. A different regex can be specified with the
8842 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
8843 directories specified in @code{#:doc-dirs} are installed as well.
8847 @defvr {Scheme Variable} cmake-build-system
8848 This variable is exported by @code{(guix build-system cmake)}. It
8849 implements the build procedure for packages using the
8850 @url{https://www.cmake.org, CMake build tool}.
8852 It automatically adds the @code{cmake} package to the set of inputs.
8853 Which package is used can be specified with the @code{#:cmake}
8856 The @code{#:configure-flags} parameter is taken as a list of flags
8857 passed to the @command{cmake} command. The @code{#:build-type}
8858 parameter specifies in abstract terms the flags passed to the compiler;
8859 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
8860 debugging information''), which roughly means that code is compiled with
8861 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
8864 @defvr {Scheme Variable} dune-build-system
8865 This variable is exported by @code{(guix build-system dune)}. It
8866 supports builds of packages using @uref{https://dune.build/, Dune}, a build
8867 tool for the OCaml programming language. It is implemented as an extension
8868 of the @code{ocaml-build-system} which is described below. As such, the
8869 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
8872 It automatically adds the @code{dune} package to the set of inputs.
8873 Which package is used can be specified with the @code{#:dune}
8876 There is no @code{configure} phase because dune packages typically don't
8877 need to be configured. The @code{#:build-flags} parameter is taken as a
8878 list of flags passed to the @code{dune} command during the build.
8880 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
8881 command instead of the more recent @code{dune} command while building
8882 a package. Its default value is @code{#f}.
8884 The @code{#:package} parameter can be passed to specify a package name, which
8885 is useful when a package contains multiple packages and you want to build
8886 only one of them. This is equivalent to passing the @code{-p} argument to
8891 @defvr {Scheme variable} elm-build-system
8892 This variable is exported by @code{(guix build-system elm)}. It implements a
8893 build procedure for @url{https://elm-lang.org, Elm} packages similar to
8896 The build system adds an Elm compiler package to the set of inputs. The
8897 default compiler package (currently @code{elm-sans-reactor}) can be overridden
8898 using the @code{#:elm} argument. Additionally, Elm packages needed by the
8899 build system itself are added as implicit inputs if they are not already
8900 present: to suppress this behavior, use the
8901 @code{#:implicit-elm-package-inputs?} argument, which is primarily useful for
8904 The @code{"dependencies"} and @code{"test-dependencies"} in an Elm package's
8905 @file{elm.json} file correspond to @code{propagated-inputs} and @code{inputs},
8908 Elm requires a particular structure for package names: @pxref{Elm Packages}
8909 for more details, including utilities provided by @code{(guix build-system
8912 There are currently a few noteworthy limitations to @code{elm-build-system}:
8916 The build system is focused on @dfn{packages} in the Elm sense of the word:
8917 Elm @dfn{projects} which declare @code{@{ "type": "package" @}} in their
8918 @file{elm.json} files. Using @code{elm-build-system} to build Elm
8919 @dfn{applications} (which declare @code{@{ "type": "application" @}}) is
8920 possible, but requires ad-hoc modifications to the build phases. For
8921 examples, see the definitions of the @code{elm-todomvc} example application and
8922 the @code{elm} package itself (because the front-end for the
8923 @samp{elm reactor} command is an Elm application).
8926 Elm supports multiple versions of a package coexisting simultaneously under
8927 @env{ELM_HOME}, but this does not yet work well with @code{elm-build-system}.
8928 This limitation primarily affects Elm applications, because they specify
8929 exact versions for their dependencies, whereas Elm packages specify supported
8930 version ranges. As a workaround, the example applications mentioned above use
8931 the @code{patch-application-dependencies} procedure provided by
8932 @code{(guix build elm-build-system)} to rewrite their @file{elm.json} files to
8933 refer to the package versions actually present in the build environment.
8934 Alternatively, Guix package transformations (@pxref{Defining Package
8935 Variants}) could be used to rewrite an application's entire dependency graph.
8938 We are not yet able to run tests for Elm projects because neither
8939 @url{https://github.com/mpizenberg/elm-test-rs, @command{elm-test-rs}} nor the
8940 Node.js-based @url{https://github.com/rtfeldman/node-test-runner,
8941 @command{elm-test}} runner has been packaged for Guix yet.
8945 @defvr {Scheme Variable} go-build-system
8946 This variable is exported by @code{(guix build-system go)}. It
8947 implements a build procedure for Go packages using the standard
8948 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
8949 Go build mechanisms}.
8951 The user is expected to provide a value for the key @code{#:import-path}
8952 and, in some cases, @code{#:unpack-path}. The
8953 @url{https://golang.org/doc/code.html#ImportPaths, import path}
8954 corresponds to the file system path expected by the package's build
8955 scripts and any referring packages, and provides a unique way to
8956 refer to a Go package. It is typically based on a combination of the
8957 package source code's remote URI and file system hierarchy structure. In
8958 some cases, you will need to unpack the package's source code to a
8959 different directory structure than the one indicated by the import path,
8960 and @code{#:unpack-path} should be used in such cases.
8962 Packages that provide Go libraries should install their source code into
8963 the built output. The key @code{#:install-source?}, which defaults to
8964 @code{#t}, controls whether or not the source code is installed. It can
8965 be set to @code{#f} for packages that only provide executable files.
8967 Packages can be cross-built, and if a specific architecture or operating
8968 system is desired then the keywords @code{#:goarch} and @code{#:goos}
8969 can be used to force the package to be built for that architecture and
8970 operating system. The combinations known to Go can be found
8971 @url{"https://golang.org/doc/install/source#environment", in their
8975 @defvr {Scheme Variable} glib-or-gtk-build-system
8976 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
8977 is intended for use with packages making use of GLib or GTK+.
8979 This build system adds the following two phases to the ones defined by
8980 @code{gnu-build-system}:
8983 @item glib-or-gtk-wrap
8984 The phase @code{glib-or-gtk-wrap} ensures that programs in
8985 @file{bin/} are able to find GLib ``schemas'' and
8986 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
8987 modules}. This is achieved by wrapping the programs in launch scripts
8988 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
8989 environment variables.
8991 It is possible to exclude specific package outputs from that wrapping
8992 process by listing their names in the
8993 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
8994 when an output is known not to contain any GLib or GTK+ binaries, and
8995 where wrapping would gratuitously add a dependency of that output on
8998 @item glib-or-gtk-compile-schemas
8999 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
9000 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
9001 GSettings schemas} of GLib are compiled. Compilation is performed by the
9002 @command{glib-compile-schemas} program. It is provided by the package
9003 @code{glib:bin} which is automatically imported by the build system.
9004 The @code{glib} package providing @command{glib-compile-schemas} can be
9005 specified with the @code{#:glib} parameter.
9008 Both phases are executed after the @code{install} phase.
9011 @defvr {Scheme Variable} guile-build-system
9012 This build system is for Guile packages that consist exclusively of Scheme
9013 code and that are so lean that they don't even have a makefile, let alone a
9014 @file{configure} script. It compiles Scheme code using @command{guild
9015 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
9016 installs the @file{.scm} and @file{.go} files in the right place. It also
9017 installs documentation.
9019 This build system supports cross-compilation by using the
9020 @option{--target} option of @samp{guild compile}.
9022 Packages built with @code{guile-build-system} must provide a Guile package in
9023 their @code{native-inputs} field.
9026 @defvr {Scheme Variable} julia-build-system
9027 This variable is exported by @code{(guix build-system julia)}. It
9028 implements the build procedure used by @uref{https://julialang.org/,
9029 julia} packages, which essentially is similar to running @samp{julia -e
9030 'using Pkg; Pkg.add(package)'} in an environment where
9031 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
9032 Tests are run by calling @code{/test/runtests.jl}.
9034 The Julia package name and uuid is read from the file
9035 @file{Project.toml}. These values can be overridden by passing the
9036 argument @code{#:julia-package-name} (which must be correctly
9037 capitalized) or @code{#:julia-package-uuid}.
9039 Julia packages usually manage their binary dependencies via
9040 @code{JLLWrappers.jl}, a Julia package that creates a module (named
9041 after the wrapped library followed by @code{_jll.jl}.
9043 To add the binary path @code{_jll.jl} packages, you need to patch the
9044 files under @file{src/wrappers/}, replacing the call to the macro
9045 @code{JLLWrappers.@@generate_wrapper_header}, adding as a second
9046 argument containing the store path the binary.
9048 As an example, in the MbedTLS Julia package, we add a build phase
9049 (@pxref{Build Phases}) to insert the absolute file name of the wrapped
9053 (add-after 'unpack 'override-binary-path
9054 (lambda* (#:key inputs #:allow-other-keys)
9055 (for-each (lambda (wrapper)
9056 (substitute* wrapper
9057 (("generate_wrapper_header.*")
9059 "generate_wrapper_header(\"MbedTLS\", \""
9060 (assoc-ref inputs "mbedtls-apache") "\")\n"))))
9061 ;; There's a Julia file for each platform, override them all.
9062 (find-files "src/wrappers/" "\\.jl$"))))
9065 Some older packages that aren't using @file{Project.toml} yet, will
9066 require this file to be created, too. It is internally done if the
9067 arguments @code{#:julia-package-name} and @code{#:julia-package-uuid}
9071 @defvr {Scheme Variable} maven-build-system
9072 This variable is exported by @code{(guix build-system maven)}. It implements
9073 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
9074 is a dependency and lifecycle management tool for Java. A user of Maven
9075 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
9076 When Maven does not have one of the dependencies or plugins in its repository,
9077 it will download them and use them to build the package.
9079 The maven build system ensures that maven will not try to download any
9080 dependency by running in offline mode. Maven will fail if a dependency is
9081 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
9082 modified to specify the version of dependencies and plugins that match the
9083 versions available in the guix build environment. Dependencies and plugins
9084 must be installed in the fake maven repository at @file{lib/m2}, and are
9085 symlinked into a proper repository before maven is run. Maven is instructed
9086 to use that repository for the build and installs built artifacts there.
9087 Changed files are copied to the @file{lib/m2} directory of the package output.
9089 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
9090 or let the build system use the default @file{pom.xml} file in the sources.
9092 In case you need to specify a dependency's version manually, you can use the
9093 @code{#:local-packages} argument. It takes an association list where the key
9094 is the groupId of the package and its value is an association list where the
9095 key is the artifactId of the package and its value is the version you want to
9096 override in the @file{pom.xml}.
9098 Some packages use dependencies or plugins that are not useful at runtime nor
9099 at build time in Guix. You can alter the @file{pom.xml} file to remove them
9100 using the @code{#:exclude} argument. Its value is an association list where
9101 the key is the groupId of the plugin or dependency you want to remove, and
9102 the value is a list of artifactId you want to remove.
9104 You can override the default @code{jdk} and @code{maven} packages with the
9105 corresponding argument, @code{#:jdk} and @code{#:maven}.
9107 The @code{#:maven-plugins} argument is a list of maven plugins used during
9108 the build, with the same format as the @code{inputs} fields of the package
9109 declaration. Its default value is @code{(default-maven-plugins)} which is
9113 @defvr {Scheme Variable} minetest-mod-build-system
9114 This variable is exported by @code{(guix build-system minetest)}. It
9115 implements a build procedure for @uref{https://www.minetest.net, Minetest}
9116 mods, which consists of copying Lua code, images and other resources to
9117 the location Minetest searches for mods. The build system also minimises
9118 PNG images and verifies that Minetest can load the mod without errors.
9121 @defvr {Scheme Variable} minify-build-system
9122 This variable is exported by @code{(guix build-system minify)}. It
9123 implements a minification procedure for simple JavaScript packages.
9125 It adds @code{uglify-js} to the set of inputs and uses it to compress
9126 all JavaScript files in the @file{src} directory. A different minifier
9127 package can be specified with the @code{#:uglify-js} parameter, but it
9128 is expected that the package writes the minified code to the standard
9131 When the input JavaScript files are not all located in the @file{src}
9132 directory, the parameter @code{#:javascript-files} can be used to
9133 specify a list of file names to feed to the minifier.
9136 @defvr {Scheme Variable} ocaml-build-system
9137 This variable is exported by @code{(guix build-system ocaml)}. It implements
9138 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
9139 of choosing the correct set of commands to run for each package. OCaml
9140 packages can expect many different commands to be run. This build system will
9143 When the package has a @file{setup.ml} file present at the top-level, it will
9144 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
9145 @code{ocaml setup.ml -install}. The build system will assume that this file
9146 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
9147 care of setting the prefix and enabling tests if they are not disabled. You
9148 can pass configure and build flags with the @code{#:configure-flags} and
9149 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
9150 set of flags used to enable tests. The @code{#:use-make?} key can be used to
9151 bypass this system in the build and install phases.
9153 When the package has a @file{configure} file, it is assumed that it is a
9154 hand-made configure script that requires a different argument format than
9155 in the @code{gnu-build-system}. You can add more flags with the
9156 @code{#:configure-flags} key.
9158 When the package has a @file{Makefile} file (or @code{#:use-make?} is
9159 @code{#t}), it will be used and more flags can be passed to the build and
9160 install phases with the @code{#:make-flags} key.
9162 Finally, some packages do not have these files and use a somewhat standard
9163 location for its build system. In that case, the build system will run
9164 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
9165 providing the path to the required findlib module. Additional flags can
9166 be passed via the @code{#:build-flags} key. Install is taken care of by
9167 @command{opam-installer}. In this case, the @code{opam} package must
9168 be added to the @code{native-inputs} field of the package definition.
9170 Note that most OCaml packages assume they will be installed in the same
9171 directory as OCaml, which is not what we want in guix. In particular, they
9172 will install @file{.so} files in their module's directory, which is usually
9173 fine because it is in the OCaml compiler directory. In guix though, these
9174 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
9175 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
9176 @file{.so} libraries should be installed.
9179 @defvr {Scheme Variable} python-build-system
9180 This variable is exported by @code{(guix build-system python)}. It
9181 implements the more or less standard build procedure used by Python
9182 packages, which consists in running @code{python setup.py build} and
9183 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
9185 For packages that install stand-alone Python programs under @code{bin/},
9186 it takes care of wrapping these programs so that their
9187 @env{GUIX_PYTHONPATH} environment variable points to all the Python
9188 libraries they depend on.
9190 Which Python package is used to perform the build can be specified with
9191 the @code{#:python} parameter. This is a useful way to force a package
9192 to be built for a specific version of the Python interpreter, which
9193 might be necessary if the package is only compatible with a single
9194 interpreter version.
9196 By default guix calls @code{setup.py} under control of
9197 @code{setuptools}, much like @command{pip} does. Some packages are not
9198 compatible with setuptools (and pip), thus you can disable this by
9199 setting the @code{#:use-setuptools?} parameter to @code{#f}.
9201 If a @code{"python"} output is available, the package is installed into it
9202 instead of the default @code{"out"} output. This is useful for packages that
9203 include a Python package as only a part of the software, and thus want to
9204 combine the phases of @code{python-build-system} with another build system.
9205 Python bindings are a common usecase.
9209 @defvr {Scheme Variable} perl-build-system
9210 This variable is exported by @code{(guix build-system perl)}. It
9211 implements the standard build procedure for Perl packages, which either
9212 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
9213 followed by @code{Build} and @code{Build install}; or in running
9214 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
9215 @code{make} and @code{make install}, depending on which of
9216 @code{Build.PL} or @code{Makefile.PL} is present in the package
9217 distribution. Preference is given to the former if both @code{Build.PL}
9218 and @code{Makefile.PL} exist in the package distribution. This
9219 preference can be reversed by specifying @code{#t} for the
9220 @code{#:make-maker?} parameter.
9222 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
9223 passes flags specified by the @code{#:make-maker-flags} or
9224 @code{#:module-build-flags} parameter, respectively.
9226 Which Perl package is used can be specified with @code{#:perl}.
9229 @defvr {Scheme Variable} renpy-build-system
9230 This variable is exported by @code{(guix build-system renpy)}. It implements
9231 the more or less standard build procedure used by Ren'py games, which consists
9232 of loading @code{#:game} once, thereby creating bytecode for it.
9234 It further creates a wrapper script in @code{bin/} and a desktop entry in
9235 @code{share/applications}, both of which can be used to launch the game.
9237 Which Ren'py package is used can be specified with @code{#:renpy}.
9238 Games can also be installed in outputs other than ``out'' by using
9242 @defvr {Scheme Variable} qt-build-system
9243 This variable is exported by @code{(guix build-system qt)}. It
9244 is intended for use with applications using Qt or KDE.
9246 This build system adds the following two phases to the ones defined by
9247 @code{cmake-build-system}:
9251 The phase @code{check-setup} prepares the environment for running
9252 the checks as commonly used by Qt test programs.
9253 For now this only sets some environment variables:
9254 @code{QT_QPA_PLATFORM=offscreen},
9255 @code{DBUS_FATAL_WARNINGS=0} and
9256 @code{CTEST_OUTPUT_ON_FAILURE=1}.
9258 This phase is added before the @code{check} phase.
9259 It's a separate phase to ease adjusting if necessary.
9262 The phase @code{qt-wrap}
9263 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
9264 and output. In case some path is found, all programs in the output's
9265 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
9266 are wrapped in scripts defining the necessary environment variables.
9268 It is possible to exclude specific package outputs from that wrapping process
9269 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
9270 This is useful when an output is known not to contain any Qt binaries, and
9271 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
9274 This phase is added after the @code{install} phase.
9278 @defvr {Scheme Variable} r-build-system
9279 This variable is exported by @code{(guix build-system r)}. It
9280 implements the build procedure used by @uref{https://r-project.org, R}
9281 packages, which essentially is little more than running @samp{R CMD
9282 INSTALL --library=/gnu/store/@dots{}} in an environment where
9283 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
9284 run after installation using the R function
9285 @code{tools::testInstalledPackage}.
9288 @defvr {Scheme Variable} rakudo-build-system
9289 This variable is exported by @code{(guix build-system rakudo)}. It
9290 implements the build procedure used by @uref{https://rakudo.org/,
9291 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
9292 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
9293 installs the binaries, library files and the resources, as well as wrap
9294 the files under the @code{bin/} directory. Tests can be skipped by
9295 passing @code{#f} to the @code{tests?} parameter.
9297 Which rakudo package is used can be specified with @code{rakudo}.
9298 Which perl6-tap-harness package used for the tests can be specified with
9299 @code{#:prove6} or removed by passing @code{#f} to the
9300 @code{with-prove6?} parameter.
9301 Which perl6-zef package used for tests and installing can be specified
9302 with @code{#:zef} or removed by passing @code{#f} to the
9303 @code{with-zef?} parameter.
9306 @defvr {Scheme Variable} rebar-build-system
9307 This variable is exported by @code{(guix build-system rebar)}. It
9308 implements a build procedure around @uref{https://rebar3.org,rebar3},
9309 a build system for programs written in the Erlang language.
9311 It adds both @code{rebar3} and the @code{erlang} to the set of inputs.
9312 Different packages can be specified with the @code{#:rebar} and
9313 @code{#:erlang} parameters, respectively.
9315 This build system is based on @code{gnu-build-system}, but with the
9316 following phases changed:
9321 This phase, after unpacking the source like the @code{gnu-build-system}
9322 does, checks for a file @code{contents.tar.gz} at the top-level of the
9323 source. If this file exists, it will be unpacked, too. This eases
9324 handling of package hosted at @uref{https://hex.pm/},
9325 the Erlang and Elixir package repository.
9329 There are no @code{bootstrap} and @code{configure} phase because erlang
9330 packages typically don’t need to be configured.
9333 This phase runs @code{rebar3 compile}
9334 with the flags listed in @code{#:rebar-flags}.
9337 Unless @code{#:tests? #f} is passed,
9338 this phase runs @code{rebar3 eunit},
9339 or some other target specified with @code{#:test-target},
9340 with the flags listed in @code{#:rebar-flags},
9343 This installs the files created in the @i{default} profile, or some
9344 other profile specified with @code{#:install-profile}.
9349 @defvr {Scheme Variable} texlive-build-system
9350 This variable is exported by @code{(guix build-system texlive)}. It is
9351 used to build TeX packages in batch mode with a specified engine. The
9352 build system sets the @env{TEXINPUTS} variable to find all TeX source
9353 files in the inputs.
9355 By default it runs @code{luatex} on all files ending on @code{ins}. A
9356 different engine and format can be specified with the
9357 @code{#:tex-format} argument. Different build targets can be specified
9358 with the @code{#:build-targets} argument, which expects a list of file
9359 names. The build system adds only @code{texlive-bin} and
9360 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
9361 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
9362 and @code{#:texlive-latex-base}, respectively.
9364 The @code{#:tex-directory} parameter tells the build system where to
9365 install the built files under the texmf tree.
9368 @defvr {Scheme Variable} ruby-build-system
9369 This variable is exported by @code{(guix build-system ruby)}. It
9370 implements the RubyGems build procedure used by Ruby packages, which
9371 involves running @code{gem build} followed by @code{gem install}.
9373 The @code{source} field of a package that uses this build system
9374 typically references a gem archive, since this is the format that Ruby
9375 developers use when releasing their software. The build system unpacks
9376 the gem archive, potentially patches the source, runs the test suite,
9377 repackages the gem, and installs it. Additionally, directories and
9378 tarballs may be referenced to allow building unreleased gems from Git or
9379 a traditional source release tarball.
9381 Which Ruby package is used can be specified with the @code{#:ruby}
9382 parameter. A list of additional flags to be passed to the @command{gem}
9383 command can be specified with the @code{#:gem-flags} parameter.
9386 @defvr {Scheme Variable} waf-build-system
9387 This variable is exported by @code{(guix build-system waf)}. It
9388 implements a build procedure around the @code{waf} script. The common
9389 phases---@code{configure}, @code{build}, and @code{install}---are
9390 implemented by passing their names as arguments to the @code{waf}
9393 The @code{waf} script is executed by the Python interpreter. Which
9394 Python package is used to run the script can be specified with the
9395 @code{#:python} parameter.
9398 @defvr {Scheme Variable} scons-build-system
9399 This variable is exported by @code{(guix build-system scons)}. It
9400 implements the build procedure used by the SCons software construction
9401 tool. This build system runs @code{scons} to build the package,
9402 @code{scons test} to run tests, and then @code{scons install} to install
9405 Additional flags to be passed to @code{scons} can be specified with the
9406 @code{#:scons-flags} parameter. The default build and install targets
9407 can be overridden with @code{#:build-targets} and
9408 @code{#:install-targets} respectively. The version of Python used to
9409 run SCons can be specified by selecting the appropriate SCons package
9410 with the @code{#:scons} parameter.
9413 @defvr {Scheme Variable} haskell-build-system
9414 This variable is exported by @code{(guix build-system haskell)}. It
9415 implements the Cabal build procedure used by Haskell packages, which
9416 involves running @code{runhaskell Setup.hs configure
9417 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
9418 Instead of installing the package by running @code{runhaskell Setup.hs
9419 install}, to avoid trying to register libraries in the read-only
9420 compiler store directory, the build system uses @code{runhaskell
9421 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
9422 addition, the build system generates the package documentation by
9423 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
9424 is passed. Optional Haddock parameters can be passed with the help of
9425 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
9426 not found, the build system looks for @code{Setup.lhs} instead.
9428 Which Haskell compiler is used can be specified with the @code{#:haskell}
9429 parameter which defaults to @code{ghc}.
9432 @defvr {Scheme Variable} dub-build-system
9433 This variable is exported by @code{(guix build-system dub)}. It
9434 implements the Dub build procedure used by D packages, which
9435 involves running @code{dub build} and @code{dub run}.
9436 Installation is done by copying the files manually.
9438 Which D compiler is used can be specified with the @code{#:ldc}
9439 parameter which defaults to @code{ldc}.
9442 @anchor{emacs-build-system}
9443 @defvr {Scheme Variable} emacs-build-system
9444 This variable is exported by @code{(guix build-system emacs)}. It
9445 implements an installation procedure similar to the packaging system
9446 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9448 It first creates the @code{@code{package}-autoloads.el} file, then it
9449 byte compiles all Emacs Lisp files. Differently from the Emacs
9450 packaging system, the Info documentation files are moved to the standard
9451 documentation directory and the @file{dir} file is deleted. The Elisp
9452 package files are installed directly under @file{share/emacs/site-lisp}.
9455 @defvr {Scheme Variable} font-build-system
9456 This variable is exported by @code{(guix build-system font)}. It
9457 implements an installation procedure for font packages where upstream
9458 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
9459 need to be copied into place. It copies font files to standard
9460 locations in the output directory.
9463 @defvr {Scheme Variable} meson-build-system
9464 This variable is exported by @code{(guix build-system meson)}. It
9465 implements the build procedure for packages that use
9466 @url{https://mesonbuild.com, Meson} as their build system.
9468 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
9469 of inputs, and they can be changed with the parameters @code{#:meson}
9470 and @code{#:ninja} if needed.
9472 This build system is an extension of @code{gnu-build-system}, but with the
9473 following phases changed to some specific for Meson:
9478 The phase runs @code{meson} with the flags specified in
9479 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
9480 @code{debugoptimized} unless something else is specified in
9481 @code{#:build-type}.
9484 The phase runs @code{ninja} to build the package in parallel by default, but
9485 this can be changed with @code{#:parallel-build?}.
9488 The phase runs @samp{meson test} with a base set of options that cannot
9489 be overridden. This base set of options can be extended via the
9490 @code{#:test-options} argument, for example to select or skip a specific
9494 The phase runs @code{ninja install} and can not be changed.
9497 Apart from that, the build system also adds the following phases:
9502 This phase ensures that all binaries can find the libraries they need.
9503 It searches for required libraries in subdirectories of the package
9504 being built, and adds those to @code{RUNPATH} where needed. It also
9505 removes references to libraries left over from the build phase by
9506 @code{meson}, such as test dependencies, that aren't actually required
9507 for the program to run.
9509 @item glib-or-gtk-wrap
9510 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9511 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9513 @item glib-or-gtk-compile-schemas
9514 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9515 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9519 @defvr {Scheme Variable} linux-module-build-system
9520 @code{linux-module-build-system} allows building Linux kernel modules.
9522 @cindex build phases
9523 This build system is an extension of @code{gnu-build-system}, but with the
9524 following phases changed:
9529 This phase configures the environment so that the Linux kernel's Makefile
9530 can be used to build the external kernel module.
9533 This phase uses the Linux kernel's Makefile in order to build the external
9537 This phase uses the Linux kernel's Makefile in order to install the external
9541 It is possible and useful to specify the Linux kernel to use for building
9542 the module (in the @code{arguments} form of a package using the
9543 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
9546 @defvr {Scheme Variable} node-build-system
9547 This variable is exported by @code{(guix build-system node)}. It
9548 implements the build procedure used by @uref{https://nodejs.org,
9549 Node.js}, which implements an approximation of the @code{npm install}
9550 command, followed by an @code{npm test} command.
9552 Which Node.js package is used to interpret the @code{npm} commands can
9553 be specified with the @code{#:node} parameter which defaults to
9557 Lastly, for packages that do not need anything as sophisticated, a
9558 ``trivial'' build system is provided. It is trivial in the sense that
9559 it provides basically no support: it does not pull any implicit inputs,
9560 and does not have a notion of build phases.
9562 @defvr {Scheme Variable} trivial-build-system
9563 This variable is exported by @code{(guix build-system trivial)}.
9565 This build system requires a @code{#:builder} argument. This argument
9566 must be a Scheme expression that builds the package output(s)---as
9567 with @code{build-expression->derivation} (@pxref{Derivations,
9568 @code{build-expression->derivation}}).
9572 @section Build Phases
9574 @cindex build phases, for packages
9575 Almost all package build systems implement a notion @dfn{build phases}:
9576 a sequence of actions that the build system executes, when you build the
9577 package, leading to the installed byproducts in the store. A notable
9578 exception is the ``bare-bones'' @code{trivial-build-system}
9579 (@pxref{Build Systems}).
9581 As discussed in the previous section, those build systems provide a
9582 standard list of phases. For @code{gnu-build-system}, the main build
9583 phases are the following:
9587 Define search path environment variables for all the input packages,
9588 including @env{PATH} (@pxref{Search Paths}).
9591 Unpack the source tarball, and change the current directory to the
9592 extracted source tree. If the source is actually a directory, copy it
9593 to the build tree, and enter that directory.
9595 @item patch-source-shebangs
9596 Patch shebangs encountered in source files so they refer to the right
9597 store file names. For instance, this changes @code{#!/bin/sh} to
9598 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
9601 Run the @file{configure} script with a number of default options, such
9602 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
9603 by the @code{#:configure-flags} argument.
9606 Run @code{make} with the list of flags specified with
9607 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
9608 (the default), build with @code{make -j}.
9611 Run @code{make check}, or some other target specified with
9612 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
9613 @code{#:parallel-tests?} argument is true (the default), run @code{make
9617 Run @code{make install} with the flags listed in @code{#:make-flags}.
9619 @item patch-shebangs
9620 Patch shebangs on the installed executable files.
9623 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
9624 is false), copying them to the @code{debug} output when available
9625 (@pxref{Installing Debugging Files}).
9627 @cindex RUNPATH, validation
9628 @anchor{phase-validate-runpath}
9629 @item validate-runpath
9630 Validate the @code{RUNPATH} of ELF binaries, unless
9631 @code{#:validate-runpath?} is false (@pxref{Build Systems}).
9633 This validation step consists in making sure that all the shared
9634 libraries needed by an ELF binary, which are listed as @code{DT_NEEDED}
9635 entries in its @code{PT_DYNAMIC} segment, appear in the
9636 @code{DT_RUNPATH} entry of that binary. In other words, it ensures that
9637 running or using those binaries will not result in a ``file not found''
9638 error at run time. @xref{Options, @option{-rpath},, ld, The GNU
9639 Linker}, for more information on @code{RUNPATH}.
9643 Other build systems have similar phases, with some variations. For
9644 example, @code{cmake-build-system} has same-named phases but its
9645 @code{configure} phases runs @code{cmake} instead of @code{./configure}.
9646 Others, such as @code{python-build-system}, have a wholly different list
9647 of standard phases. All this code runs on the @dfn{build side}: it is
9648 evaluated when you actually build the package, in a dedicated build
9649 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
9651 Build phases are represented as association lists or ``alists''
9652 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
9653 each key is a symbol for the name of the phase and the associated value
9654 is a procedure that accepts an arbitrary number of arguments. By
9655 convention, those procedures receive information about the build in the
9656 form of @dfn{keyword parameters}, which they can use or ignore.
9658 @vindex %standard-phases
9659 For example, here is how @code{(guix build gnu-build-system)} defines
9660 @code{%standard-phases}, the variable holding its alist of build
9661 phases@footnote{We present a simplified view of those build phases, but
9662 do take a look at @code{(guix build gnu-build-system)} to see all the
9666 ;; The build phases of 'gnu-build-system'.
9668 (define* (unpack #:key source #:allow-other-keys)
9669 ;; Extract the source tarball.
9670 (invoke "tar" "xvf" source))
9672 (define* (configure #:key outputs #:allow-other-keys)
9673 ;; Run the 'configure' script. Install to output "out".
9674 (let ((out (assoc-ref outputs "out")))
9675 (invoke "./configure"
9676 (string-append "--prefix=" out))))
9678 (define* (build #:allow-other-keys)
9682 (define* (check #:key (test-target "check") (tests? #true)
9684 ;; Run the test suite.
9686 (invoke "make" test-target)
9687 (display "test suite not run\n")))
9689 (define* (install #:allow-other-keys)
9690 ;; Install files to the prefix 'configure' specified.
9691 (invoke "make" "install"))
9693 (define %standard-phases
9694 ;; The list of standard phases (quite a few are omitted
9695 ;; for brevity). Each element is a symbol/procedure pair.
9696 (list (cons 'unpack unpack)
9697 (cons 'configure configure)
9700 (cons 'install install)))
9703 This shows how @code{%standard-phases} is defined as a list of
9704 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
9705 Manual}). The first pair associates the @code{unpack} procedure with
9706 the @code{unpack} symbol---a name; the second pair defines the
9707 @code{configure} phase similarly, and so on. When building a package
9708 that uses @code{gnu-build-system} with its default list of phases, those
9709 phases are executed sequentially. You can see the name of each phase
9710 started and completed in the build log of packages that you build.
9712 Let's now look at the procedures themselves. Each one is defined with
9713 @code{define*}: @code{#:key} lists keyword parameters the procedure
9714 accepts, possibly with a default value, and @code{#:allow-other-keys}
9715 specifies that other keyword parameters are ignored (@pxref{Optional
9716 Arguments,,, guile, GNU Guile Reference Manual}).
9718 The @code{unpack} procedure honors the @code{source} parameter, which
9719 the build system uses to pass the file name of the source tarball (or
9720 version control checkout), and it ignores other parameters. The
9721 @code{configure} phase only cares about the @code{outputs} parameter, an
9722 alist mapping package output names to their store file name
9723 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
9724 for @code{out}, the default output, and passes it to
9725 @command{./configure} as the installation prefix, meaning that
9726 @command{make install} will eventually copy all the files in that
9727 directory (@pxref{Configuration, configuration and makefile
9728 conventions,, standards, GNU Coding Standards}). @code{build} and
9729 @code{install} ignore all their arguments. @code{check} honors the
9730 @code{test-target} argument, which specifies the name of the Makefile
9731 target to run tests; it prints a message and skips tests when
9732 @code{tests?} is false.
9734 @cindex build phases, customizing
9735 The list of phases used for a particular package can be changed with the
9736 @code{#:phases} parameter of the build system. Changing the set of
9737 build phases boils down to building a new alist of phases based on the
9738 @code{%standard-phases} alist described above. This can be done with
9739 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
9740 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
9741 more convenient to do so with @code{modify-phases} (@pxref{Build
9742 Utilities, @code{modify-phases}}).
9744 Here is an example of a package definition that removes the
9745 @code{configure} phase of @code{%standard-phases} and inserts a new
9746 phase before the @code{build} phase, called
9747 @code{set-prefix-in-makefile}:
9750 (define-public example
9753 ;; other fields omitted
9754 (build-system gnu-build-system)
9756 '(#:phases (modify-phases %standard-phases
9758 (add-before 'build 'set-prefix-in-makefile
9759 (lambda* (#:key outputs #:allow-other-keys)
9760 ;; Modify the makefile so that its
9761 ;; 'PREFIX' variable points to "out".
9762 (let ((out (assoc-ref outputs "out")))
9763 (substitute* "Makefile"
9765 (string-append "PREFIX = "
9769 The new phase that is inserted is written as an anonymous procedure,
9770 introduced with @code{lambda*}; it honors the @code{outputs} parameter
9771 we have seen before. @xref{Build Utilities}, for more about the helpers
9772 used by this phase, and for more examples of @code{modify-phases}.
9774 @cindex code staging
9775 @cindex staging, of code
9776 Keep in mind that build phases are code evaluated at the time the
9777 package is actually built. This explains why the whole
9778 @code{modify-phases} expression above is quoted (it comes after the
9779 @code{'} or apostrophe): it is @dfn{staged} for later execution.
9780 @xref{G-Expressions}, for an explanation of code staging and the
9781 @dfn{code strata} involved.
9783 @node Build Utilities
9784 @section Build Utilities
9786 As soon as you start writing non-trivial package definitions
9787 (@pxref{Defining Packages}) or other build actions
9788 (@pxref{G-Expressions}), you will likely start looking for helpers for
9789 ``shell-like'' actions---creating directories, copying and deleting
9790 files recursively, manipulating build phases, and so on. The
9791 @code{(guix build utils)} module provides such utility procedures.
9793 Most build systems load @code{(guix build utils)} (@pxref{Build
9794 Systems}). Thus, when writing custom build phases for your package
9795 definitions, you can usually assume those procedures are in scope.
9797 When writing G-expressions, you can import @code{(guix build utils)} on
9798 the ``build side'' using @code{with-imported-modules} and then put it in
9799 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
9800 guile, GNU Guile Reference Manual}):
9803 (with-imported-modules '((guix build utils)) ;import it
9804 (computed-file "empty-tree"
9807 (use-modules (guix build utils))
9809 ;; Happily use its 'mkdir-p' procedure.
9810 (mkdir-p (string-append #$output "/a/b/c")))))
9813 The remainder of this section is the reference for most of the utility
9814 procedures provided by @code{(guix build utils)}.
9816 @c TODO Document what's missing.
9818 @subsection Dealing with Store File Names
9820 This section documents procedures that deal with store file names.
9822 @deffn {Scheme Procedure} %store-directory
9823 Return the directory name of the store.
9826 @deffn {Scheme Procedure} store-file-name? @var{file}
9827 Return true if @var{file} is in the store.
9830 @deffn {Scheme Procedure} strip-store-file-name @var{file}
9831 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
9832 The result is typically a @code{"@var{package}-@var{version}"} string.
9835 @deffn {Scheme Procedure} package-name->name+version @var{name}
9836 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
9837 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
9838 unavailable, @var{name} and @code{#f} are returned. The first hyphen
9839 followed by a digit is considered to introduce the version part.
9842 @subsection File Types
9844 The procedures below deal with files and file types.
9846 @deffn {Scheme Procedure} directory-exists? @var{dir}
9847 Return @code{#t} if @var{dir} exists and is a directory.
9850 @deffn {Scheme Procedure} executable-file? @var{file}
9851 Return @code{#t} if @var{file} exists and is executable.
9854 @deffn {Scheme Procedure} symbolic-link? @var{file}
9855 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
9858 @deffn {Scheme Procedure} elf-file? @var{file}
9859 @deffnx {Scheme Procedure} ar-file? @var{file}
9860 @deffnx {Scheme Procedure} gzip-file? @var{file}
9861 Return @code{#t} if @var{file} is, respectively, an ELF file, an
9862 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
9865 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
9866 If @var{file} is a gzip file, reset its embedded timestamp (as with
9867 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
9868 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
9871 @subsection File Manipulation
9873 The following procedures and macros help create, modify, and delete
9874 files. They provide functionality comparable to common shell utilities
9875 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
9876 @command{sed}. They complement Guile's extensive, but low-level, file
9877 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
9879 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
9880 Run @var{body} with @var{directory} as the process's current directory.
9882 Essentially, this macro changes the current directory to @var{directory}
9883 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
9884 guile, GNU Guile Reference Manual}). It changes back to the initial
9885 directory when the dynamic extent of @var{body} is left, be it @i{via}
9886 normal procedure return or @i{via} a non-local exit such as an
9890 @deffn {Scheme Procedure} mkdir-p @var{dir}
9891 Create directory @var{dir} and all its ancestors.
9894 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
9895 Create @var{directory} if it does not exist and copy @var{file} in there
9896 under the same name.
9899 @deffn {Scheme Procedure} make-file-writable @var{file}
9900 Make @var{file} writable for its owner.
9903 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
9904 [#:log (current-output-port)] [#:follow-symlinks? #f] @
9905 [#:copy-file copy-file] [#:keep-mtime? #f] [#:keep-permissions? #t]
9906 Copy @var{source} directory to @var{destination}. Follow symlinks if
9907 @var{follow-symlinks?} is true; otherwise, just preserve them. Call
9908 @var{copy-file} to copy regular files. When @var{keep-mtime?} is true,
9909 keep the modification time of the files in @var{source} on those of
9910 @var{destination}. When @var{keep-permissions?} is true, preserve file
9911 permissions. Write verbose output to the @var{log} port.
9914 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
9915 [#:follow-mounts? #f]
9916 Delete @var{dir} recursively, like @command{rm -rf}, without following
9917 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
9918 is true. Report but ignore errors.
9921 @deffn {Scheme Syntax} substitute* @var{file} @
9922 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
9923 Substitute @var{regexp} in @var{file} by the string returned by
9924 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
9925 the corresponding positional regexp sub-expression. For example:
9931 (("foo([a-z]+)bar(.*)$" all letters end)
9932 (string-append "baz" letters end)))
9935 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
9936 by @code{good morning}. Anytime a line of @var{file} matches the second
9937 regexp, @code{all} is bound to the complete match, @code{letters} is bound
9938 to the first sub-expression, and @code{end} is bound to the last one.
9940 When one of the @var{match-var} is @code{_}, no variable is bound to the
9941 corresponding match substring.
9943 Alternatively, @var{file} may be a list of file names, in which case
9944 they are all subject to the substitutions.
9946 Be careful about using @code{$} to match the end of a line; by itself it
9947 won't match the terminating newline of a line.
9950 @subsection File Search
9952 @cindex file, searching
9953 This section documents procedures to search and filter files.
9955 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
9956 Return a predicate that returns true when passed a file name whose base
9957 name matches @var{regexp}.
9960 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
9961 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
9962 Return the lexicographically sorted list of files under @var{dir} for
9963 which @var{pred} returns true. @var{pred} is passed two arguments: the
9964 absolute file name, and its stat buffer; the default predicate always
9965 returns true. @var{pred} can also be a regular expression, in which
9966 case it is equivalent to @code{(file-name-predicate @var{pred})}.
9967 @var{stat} is used to obtain file information; using @code{lstat} means
9968 that symlinks are not followed. If @var{directories?} is true, then
9969 directories will also be included. If @var{fail-on-error?} is true,
9970 raise an exception upon error.
9973 Here are a few examples where we assume that the current directory is
9974 the root of the Guix source tree:
9977 ;; List all the regular files in the current directory.
9979 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
9981 ;; List all the .scm files under gnu/services.
9982 (find-files "gnu/services" "\\.scm$")
9983 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
9985 ;; List ar files in the current directory.
9986 (find-files "." (lambda (file stat) (ar-file? file)))
9987 @result{} ("./libformat.a" "./libstore.a" @dots{})
9990 @deffn {Scheme Procedure} which @var{program}
9991 Return the complete file name for @var{program} as found in
9992 @code{$PATH}, or @code{#f} if @var{program} could not be found.
9995 @deffn {Scheme Procedure} search-input-file @var{inputs} @var{name}
9996 @deffnx {Scheme Procedure} search-input-directory @var{inputs} @var{name}
9997 Return the complete file name for @var{name} as found in @var{inputs};
9998 @code{search-input-file} searches for a regular file and
9999 @code{search-input-directory} searches for a directory. If @var{name}
10000 could not be found, an exception is raised.
10002 Here, @var{inputs} must be an association list like @code{inputs} and
10003 @code{native-inputs} as available to build phases (@pxref{Build
10007 Here is a (simplified) example of how @code{search-input-file} is used
10008 in a build phase of the @code{wireguard-tools} package:
10011 (add-after 'install 'wrap-wg-quick
10012 (lambda* (#:key inputs outputs #:allow-other-keys)
10013 (let ((coreutils (string-append (assoc-ref inputs "coreutils")
10015 (wrap-program (search-input-file outputs "bin/wg-quick")
10016 #:sh (search-input-file inputs "bin/bash")
10017 `("PATH" ":" prefix ,(list coreutils))))))
10020 @subsection Program Invocation
10022 @cindex program invocation, from Scheme
10023 @cindex invoking programs, from Scheme
10024 You'll find handy procedures to spawn processes in this module,
10025 essentially convenient wrappers around Guile's @code{system*}
10026 (@pxref{Processes, @code{system*},, guile, GNU Guile Reference Manual}).
10028 @deffn {Scheme Procedure} invoke @var{program} @var{args}@dots{}
10029 Invoke @var{program} with the given @var{args}. Raise an
10030 @code{&invoke-error} exception if the exit code is non-zero; otherwise
10033 The advantage compared to @code{system*} is that you do not need to
10034 check the return value. This reduces boilerplate in shell-script-like
10035 snippets for instance in package build phases.
10038 @deffn {Scheme Procedure} invoke-error? @var{c}
10039 Return true if @var{c} is an @code{&invoke-error} condition.
10042 @deffn {Scheme Procedure} invoke-error-program @var{c}
10043 @deffnx {Scheme Procedure} invoke-error-arguments @var{c}
10044 @deffnx {Scheme Procedure} invoke-error-exit-status @var{c}
10045 @deffnx {Scheme Procedure} invoke-error-term-signal @var{c}
10046 @deffnx {Scheme Procedure} invoke-error-stop-signal @var{c}
10047 Access specific fields of @var{c}, an @code{&invoke-error} condition.
10050 @deffn {Scheme Procedure} report-invoke-error @var{c} [@var{port}]
10051 Report to @var{port} (by default the current error port) about @var{c},
10052 an @code{&invoke-error} condition, in a human-friendly way.
10054 Typical usage would look like this:
10057 (use-modules (srfi srfi-34) ;for 'guard'
10058 (guix build utils))
10060 (guard (c ((invoke-error? c)
10061 (report-invoke-error c)))
10062 (invoke "date" "--imaginary-option"))
10064 @print{} command "date" "--imaginary-option" failed with status 1
10068 @deffn {Scheme Procedure} invoke/quiet @var{program} @var{args}@dots{}
10069 Invoke @var{program} with @var{args} and capture @var{program}'s
10070 standard output and standard error. If @var{program} succeeds, print
10071 nothing and return the unspecified value; otherwise, raise a
10072 @code{&message} error condition that includes the status code and the
10073 output of @var{program}.
10078 (use-modules (srfi srfi-34) ;for 'guard'
10079 (srfi srfi-35) ;for 'message-condition?'
10080 (guix build utils))
10082 (guard (c ((message-condition? c)
10083 (display (condition-message c))))
10084 (invoke/quiet "date") ;all is fine
10085 (invoke/quiet "date" "--imaginary-option"))
10087 @print{} 'date --imaginary-option' exited with status 1; output follows:
10089 date: unrecognized option '--imaginary-option'
10090 Try 'date --help' for more information.
10094 @subsection Build Phases
10096 @cindex build phases
10097 The @code{(guix build utils)} also contains tools to manipulate build
10098 phases as used by build systems (@pxref{Build Systems}). Build phases
10099 are represented as association lists or ``alists'' (@pxref{Association
10100 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
10101 naming the phase and the associated value is a procedure (@pxref{Build
10104 Guile core and the @code{(srfi srfi-1)} module both provide tools to
10105 manipulate alists. The @code{(guix build utils)} module complements
10106 those with tools written with build phases in mind.
10108 @cindex build phases, modifying
10109 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
10110 Modify @var{phases} sequentially as per each @var{clause}, which may
10111 have one of the following forms:
10114 (delete @var{old-phase-name})
10115 (replace @var{old-phase-name} @var{new-phase})
10116 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10117 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10120 Where every @var{phase-name} above is an expression evaluating to a
10121 symbol, and @var{new-phase} an expression evaluating to a procedure.
10124 The example below is taken from the definition of the @code{grep}
10125 package. It adds a phase to run after the @code{install} phase, called
10126 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
10127 is for anonymous procedures) that takes a @code{#:outputs} keyword
10128 argument and ignores extra keyword arguments (@pxref{Optional
10129 Arguments,,, guile, GNU Guile Reference Manual}, for more on
10130 @code{lambda*} and optional and keyword arguments.) The phase uses
10131 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
10132 scripts so that they refer to @code{grep} by its absolute file name:
10135 (modify-phases %standard-phases
10136 (add-after 'install 'fix-egrep-and-fgrep
10137 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
10138 ;; absolute file name instead of searching for it in $PATH.
10139 (lambda* (#:key outputs #:allow-other-keys)
10140 (let* ((out (assoc-ref outputs "out"))
10141 (bin (string-append out "/bin")))
10142 (substitute* (list (string-append bin "/egrep")
10143 (string-append bin "/fgrep"))
10145 (string-append "exec " bin "/grep")))))))
10148 In the example below, phases are modified in two ways: the standard
10149 @code{configure} phase is deleted, presumably because the package does
10150 not have a @file{configure} script or anything similar, and the default
10151 @code{install} phase is replaced by one that manually copies the
10152 executable files to be installed:
10155 (modify-phases %standard-phases
10156 (delete 'configure) ;no 'configure' script
10158 (lambda* (#:key outputs #:allow-other-keys)
10159 ;; The package's Makefile doesn't provide an "install"
10160 ;; rule so do it by ourselves.
10161 (let ((bin (string-append (assoc-ref outputs "out")
10163 (install-file "footswitch" bin)
10164 (install-file "scythe" bin)))))
10167 @c TODO: Add more examples.
10169 @subsection Wrappers
10171 @cindex program wrappers
10172 @cindex wrapping programs
10173 It is not unusual for a command to require certain environment variables
10174 to be set for proper functioning, typically search paths (@pxref{Search
10175 Paths}). Failing to do that, the command might fail to find files or
10176 other commands it relies on, or it might pick the ``wrong''
10177 ones---depending on the environment in which it runs. Examples include:
10181 a shell script that assumes all the commands it uses are in @env{PATH};
10184 a Guile program that assumes all its modules are in @env{GUILE_LOAD_PATH}
10185 and @env{GUILE_LOAD_COMPILED_PATH};
10188 a Qt application that expects to find certain plugins in
10189 @env{QT_PLUGIN_PATH}.
10192 For a package writer, the goal is to make sure commands always work the
10193 same rather than depend on some external settings. One way to achieve
10194 that is to @dfn{wrap} commands in a thin script that sets those
10195 environment variables, thereby ensuring that those run-time dependencies
10196 are always found. The wrapper would be used to set @env{PATH},
10197 @env{GUILE_LOAD_PATH}, or @env{QT_PLUGIN_PATH} in the examples above.
10199 To ease that task, the @code{(guix build utils)} module provides a
10200 couple of helpers to wrap commands.
10202 @deffn {Scheme Procedure} wrap-program @var{program} @
10203 [#:sh @var{sh}] [#:rest @var{variables}]
10204 Make a wrapper for @var{program}. @var{variables} should look like this:
10207 '(@var{variable} @var{delimiter} @var{position} @var{list-of-directories})
10210 where @var{delimiter} is optional. @code{:} will be used if
10211 @var{delimiter} is not given.
10213 For example, this call:
10216 (wrap-program "foo"
10217 '("PATH" ":" = ("/gnu/.../bar/bin"))
10218 '("CERT_PATH" suffix ("/gnu/.../baz/certs"
10222 will copy @file{foo} to @file{.foo-real} and create the file @file{foo}
10223 with the following contents:
10226 #!location/of/bin/bash
10227 export PATH="/gnu/.../bar/bin"
10228 export CERT_PATH="$CERT_PATH$@{CERT_PATH:+:@}/gnu/.../baz/certs:/qux/certs"
10229 exec -a $0 location/of/.foo-real "$@@"
10232 If @var{program} has previously been wrapped by @code{wrap-program}, the
10233 wrapper is extended with definitions for @var{variables}. If it is not,
10234 @var{sh} will be used as the interpreter.
10237 @deffn {Scheme Procedure} wrap-script @var{program} @
10238 [#:guile @var{guile}] [#:rest @var{variables}]
10239 Wrap the script @var{program} such that @var{variables} are set first.
10240 The format of @var{variables} is the same as in the @code{wrap-program}
10241 procedure. This procedure differs from @code{wrap-program} in that it
10242 does not create a separate shell script. Instead, @var{program} is
10243 modified directly by prepending a Guile script, which is interpreted as
10244 a comment in the script's language.
10246 Special encoding comments as supported by Python are recreated on the
10249 Note that this procedure can only be used once per file as Guile scripts are
10254 @section Search Paths
10256 @cindex search path
10257 Many programs and libraries look for input data in a @dfn{search path},
10258 a list of directories: shells like Bash look for executables in the
10259 command search path, a C compiler looks for @file{.h} files in its
10260 header search path, the Python interpreter looks for @file{.py}
10261 files in its search path, the spell checker has a search path for
10262 dictionaries, and so on.
10264 Search paths can usually be defined or overridden @i{via} environment
10265 variables (@pxref{Environment Variables,,, libc, The GNU C Library
10266 Reference Manual}). For example, the search paths mentioned above can
10267 be changed by defining the @env{PATH}, @env{C_INCLUDE_PATH},
10268 @env{PYTHONPATH} (or @env{GUIX_PYTHONPATH}), and @env{DICPATH}
10269 environment variables---you know, all these something-PATH variables
10270 that you need to get right or things ``won't be found''.
10272 You may have noticed from the command line that Guix ``knows'' which
10273 search path environment variables should be defined, and how. When you
10274 install packages in your default profile, the file
10275 @file{~/.guix-profile/etc/profile} is created, which you can ``source''
10276 from the shell to set those variables. Likewise, if you ask
10277 @command{guix shell} to create an environment containing Python and
10278 NumPy, a Python library, and if you pass it the @option{--search-paths}
10279 option, it will tell you about @env{PATH} and @env{GUIX_PYTHONPATH}
10280 (@pxref{Invoking guix shell}):
10283 $ guix shell python python-numpy --pure --search-paths
10284 export PATH="/gnu/store/@dots{}-profile/bin"
10285 export GUIX_PYTHONPATH="/gnu/store/@dots{}-profile/lib/python3.9/site-packages"
10288 When you omit @option{--search-paths}, it defines these environment
10289 variables right away, such that Python can readily find NumPy:
10292 $ guix shell python python-numpy -- python3
10293 Python 3.9.6 (default, Jan 1 1970, 00:00:01)
10294 [GCC 10.3.0] on linux
10295 Type "help", "copyright", "credits" or "license" for more information.
10297 >>> numpy.version.version
10301 For this to work, the definition of the @code{python} package
10302 @emph{declares} the search path it cares about and its associated
10303 environment variable, @env{GUIX_PYTHONPATH}. It looks like this:
10309 ;; some fields omitted...
10310 (native-search-paths
10311 (list (search-path-specification
10312 (variable "GUIX_PYTHONPATH")
10313 (files (list "lib/python/3.9/site-packages"))))))
10316 What this @code{native-search-paths} field says is that, when the
10317 @code{python} package is used, the @env{GUIX_PYTHONPATH} environment
10318 variable must be defined to include all the
10319 @file{lib/python/3.9/site-packages} sub-directories encountered in its
10320 environment. (The @code{native-} bit means that, if we are in a
10321 cross-compilation environment, only native inputs may be added to the
10322 search path; @pxref{package Reference, @code{search-paths}}.)
10323 In the NumPy example above, the profile where
10324 @code{python} appears contains exactly one such sub-directory, and
10325 @env{GUIX_PYTHONPATH} is set to that. When there are several
10326 @file{lib/python/3.9/site-packages}---this is the case in package build
10327 environments---they are all added to @env{GUIX_PYTHONPATH}, separated by
10331 Notice that @env{GUIX_PYTHONPATH} is specified as part of the definition
10332 of the @code{python} package, and @emph{not} as part of that of
10333 @code{python-numpy}. This is because this environment variable
10334 ``belongs'' to Python, not NumPy: Python actually reads the value of
10335 that variable and honors it.
10337 Corollary: if you create a profile that does not contain @code{python},
10338 @code{GUIX_PYTHONPATH} will @emph{not} be defined, even if it contains
10339 packages that provide @file{.py} files:
10342 $ guix shell python-numpy --search-paths --pure
10343 export PATH="/gnu/store/@dots{}-profile/bin"
10346 This makes a lot of sense if we look at this profile in isolation: no
10347 software in this profile would read @env{GUIX_PYTHONPATH}.
10350 Of course, there are many variations on that theme: some packages honor
10351 more than one search path, some use separators other than colon, some
10352 accumulate several directories in their search path, and so on. A more
10353 complex example is the search path of libxml2: the value of the
10354 @env{XML_CATALOG_FILES} environment variable is space-separated, it must
10355 contain a list of @file{catalog.xml} files (not directories), which are
10356 to be found in @file{xml} sub-directories---nothing less. The search
10357 path specification looks like this:
10362 ;; some fields omitted
10363 (native-search-paths
10364 (list (search-path-specification
10365 (variable "XML_CATALOG_FILES")
10368 (file-pattern "^catalog\\.xml$")
10369 (file-type 'regular)))))
10372 Worry not, search path specifications are usually not this tricky.
10374 The @code{(guix search-paths)} module defines the data type of search
10375 path specifications and a number of helper procedures. Below is the
10376 reference of search path specifications.
10378 @deftp {Data Type} search-path-specification
10379 The data type for search path specifications.
10382 @item @code{variable}
10383 The name of the environment variable for this search path (a string).
10386 The list of sub-directories (strings) that should be added to the search
10389 @item @code{separator} (default: @code{":"})
10390 The string used to separate search path components.
10392 As a special case, a @code{separator} value of @code{#f} specifies a
10393 ``single-component search path''---in other words, a search path that
10394 cannot contain more than one element. This is useful in some cases,
10395 such as the @code{SSL_CERT_DIR} variable (honored by OpenSSL, cURL, and
10396 a few other packages) or the @code{ASPELL_DICT_DIR} variable (honored by
10397 the GNU Aspell spell checker), both of which must point to a single
10400 @item @code{file-type} (default: @code{'directory})
10401 The type of file being matched---@code{'directory} or @code{'regular},
10402 though it can be any symbol returned by @code{stat:type} (@pxref{File
10403 System, @code{stat},, guile, GNU Guile Reference Manual}).
10405 In the libxml2 example above, we would match regular files; in the
10406 Python example, we would match directories.
10408 @item @code{file-pattern} (default: @code{#f})
10409 This must be either @code{#f} or a regular expression specifying
10410 files to be matched @emph{within} the sub-directories specified by the
10411 @code{files} field.
10413 Again, the libxml2 example shows a situation where this is needed.
10417 Some search paths are not tied by a single package but to many packages.
10418 To reduce duplications, some of them are pre-defined in @code{(guix
10421 @defvr {Scheme Variable} $SSL_CERT_DIR
10422 @defvrx {Scheme Variable} $SSL_CERT_FILE
10423 These two search paths indicate where X.509 certificates can be found
10424 (@pxref{X.509 Certificates}).
10427 These pre-defined search paths can be used as in the following example:
10432 ;; some fields omitted ...
10433 (native-search-paths (list $SSL_CERT_DIR $SSL_CERT_FILE)))
10436 How do you turn search path specifications on one hand and a bunch of
10437 directories on the other hand in a set of environment variable
10438 definitions? That's the job of @code{evaluate-search-paths}.
10440 @deffn {Scheme Procedure} evaluate-search-paths @var{search-paths} @
10441 @var{directories} [@var{getenv}]
10442 Evaluate @var{search-paths}, a list of search-path specifications, for
10443 @var{directories}, a list of directory names, and return a list of
10444 specification/value pairs. Use @var{getenv} to determine the current
10445 settings and report only settings not already effective.
10448 The @code{(guix profiles)} provides a higher-level helper procedure,
10449 @code{load-profile}, that sets the environment variables of a profile.
10455 @cindex store items
10456 @cindex store paths
10458 Conceptually, the @dfn{store} is the place where derivations that have
10459 been built successfully are stored---by default, @file{/gnu/store}.
10460 Sub-directories in the store are referred to as @dfn{store items} or
10461 sometimes @dfn{store paths}. The store has an associated database that
10462 contains information such as the store paths referred to by each store
10463 path, and the list of @emph{valid} store items---results of successful
10464 builds. This database resides in @file{@var{localstatedir}/guix/db},
10465 where @var{localstatedir} is the state directory specified @i{via}
10466 @option{--localstatedir} at configure time, usually @file{/var}.
10468 The store is @emph{always} accessed by the daemon on behalf of its clients
10469 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
10470 connect to the daemon over a Unix-domain socket, send requests to it,
10471 and read the result---these are remote procedure calls, or RPCs.
10474 Users must @emph{never} modify files under @file{/gnu/store} directly.
10475 This would lead to inconsistencies and break the immutability
10476 assumptions of Guix's functional model (@pxref{Introduction}).
10478 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
10479 how to check the integrity of the store and attempt recovery from
10480 accidental modifications.
10483 The @code{(guix store)} module provides procedures to connect to the
10484 daemon, and to perform RPCs. These are described below. By default,
10485 @code{open-connection}, and thus all the @command{guix} commands,
10486 connect to the local daemon or to the URI specified by the
10487 @env{GUIX_DAEMON_SOCKET} environment variable.
10489 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
10490 When set, the value of this variable should be a file name or a URI
10491 designating the daemon endpoint. When it is a file name, it denotes a
10492 Unix-domain socket to connect to. In addition to file names, the
10493 supported URI schemes are:
10498 These are for Unix-domain sockets.
10499 @code{file:///var/guix/daemon-socket/socket} is equivalent to
10500 @file{/var/guix/daemon-socket/socket}.
10503 @cindex daemon, remote access
10504 @cindex remote access to the daemon
10505 @cindex daemon, cluster setup
10506 @cindex clusters, daemon setup
10507 These URIs denote connections over TCP/IP, without encryption nor
10508 authentication of the remote host. The URI must specify the host name
10509 and optionally a port number (by default port 44146 is used):
10512 guix://master.guix.example.org:1234
10515 This setup is suitable on local networks, such as clusters, where only
10516 trusted nodes may connect to the build daemon at
10517 @code{master.guix.example.org}.
10519 The @option{--listen} option of @command{guix-daemon} can be used to
10520 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
10521 @option{--listen}}).
10524 @cindex SSH access to build daemons
10525 These URIs allow you to connect to a remote daemon over SSH@. This
10526 feature requires Guile-SSH (@pxref{Requirements}) and a working
10527 @command{guile} binary in @env{PATH} on the destination machine. It
10528 supports public key and GSSAPI authentication. A typical URL might look
10532 ssh://charlie@@guix.example.org:22
10535 As for @command{guix copy}, the usual OpenSSH client configuration files
10536 are honored (@pxref{Invoking guix copy}).
10539 Additional URI schemes may be supported in the future.
10541 @c XXX: Remove this note when the protocol incurs fewer round trips
10542 @c and when (guix derivations) no longer relies on file system access.
10544 The ability to connect to remote build daemons is considered
10545 experimental as of @value{VERSION}. Please get in touch with us to
10546 share any problems or suggestions you may have (@pxref{Contributing}).
10550 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
10551 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
10552 @var{reserve-space?} is true, instruct it to reserve a little bit of
10553 extra space on the file system so that the garbage collector can still
10554 operate should the disk become full. Return a server object.
10556 @var{file} defaults to @code{%default-socket-path}, which is the normal
10557 location given the options that were passed to @command{configure}.
10560 @deffn {Scheme Procedure} close-connection @var{server}
10561 Close the connection to @var{server}.
10564 @defvr {Scheme Variable} current-build-output-port
10565 This variable is bound to a SRFI-39 parameter, which refers to the port
10566 where build and error logs sent by the daemon should be written.
10569 Procedures that make RPCs all take a server object as their first
10572 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
10573 @cindex invalid store items
10574 Return @code{#t} when @var{path} designates a valid store item and
10575 @code{#f} otherwise (an invalid item may exist on disk but still be
10576 invalid, for instance because it is the result of an aborted or failed
10579 A @code{&store-protocol-error} condition is raised if @var{path} is not
10580 prefixed by the store directory (@file{/gnu/store}).
10583 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
10584 Add @var{text} under file @var{name} in the store, and return its store
10585 path. @var{references} is the list of store paths referred to by the
10586 resulting store path.
10589 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
10591 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
10592 file names, or derivation/output pairs, using the specified
10593 @var{mode}---@code{(build-mode normal)} by default.
10596 Note that the @code{(guix monads)} module provides a monad as well as
10597 monadic versions of the above procedures, with the goal of making it
10598 more convenient to work with code that accesses the store (@pxref{The
10602 @i{This section is currently incomplete.}
10605 @section Derivations
10607 @cindex derivations
10608 Low-level build actions and the environment in which they are performed
10609 are represented by @dfn{derivations}. A derivation contains the
10610 following pieces of information:
10614 The outputs of the derivation---derivations produce at least one file or
10615 directory in the store, but may produce more.
10618 @cindex build-time dependencies
10619 @cindex dependencies, build-time
10620 The inputs of the derivations---i.e., its build-time dependencies---which may
10621 be other derivations or plain files in the store (patches, build scripts,
10625 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
10628 The file name of a build script in the store, along with the arguments
10632 A list of environment variables to be defined.
10636 @cindex derivation path
10637 Derivations allow clients of the daemon to communicate build actions to
10638 the store. They exist in two forms: as an in-memory representation,
10639 both on the client- and daemon-side, and as files in the store whose
10640 name end in @file{.drv}---these files are referred to as @dfn{derivation
10641 paths}. Derivations paths can be passed to the @code{build-derivations}
10642 procedure to perform the build actions they prescribe (@pxref{The
10645 @cindex fixed-output derivations
10646 Operations such as file downloads and version-control checkouts for
10647 which the expected content hash is known in advance are modeled as
10648 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
10649 of a fixed-output derivation are independent of its inputs---e.g., a
10650 source code download produces the same result regardless of the download
10651 method and tools being used.
10654 @cindex run-time dependencies
10655 @cindex dependencies, run-time
10656 The outputs of derivations---i.e., the build results---have a set of
10657 @dfn{references}, as reported by the @code{references} RPC or the
10658 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
10659 are the set of run-time dependencies of the build results. References are a
10660 subset of the inputs of the derivation; this subset is automatically computed
10661 by the build daemon by scanning all the files in the outputs.
10663 The @code{(guix derivations)} module provides a representation of
10664 derivations as Scheme objects, along with procedures to create and
10665 otherwise manipulate derivations. The lowest-level primitive to create
10666 a derivation is the @code{derivation} procedure:
10668 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
10669 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10670 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
10671 [#:system (%current-system)] [#:references-graphs #f] @
10672 [#:allowed-references #f] [#:disallowed-references #f] @
10673 [#:leaked-env-vars #f] [#:local-build? #f] @
10674 [#:substitutable? #t] [#:properties '()]
10675 Build a derivation with the given arguments, and return the resulting
10676 @code{<derivation>} object.
10678 When @var{hash} and @var{hash-algo} are given, a
10679 @dfn{fixed-output derivation} is created---i.e., one whose result is
10680 known in advance, such as a file download. If, in addition,
10681 @var{recursive?} is true, then that fixed output may be an executable
10682 file or a directory and @var{hash} must be the hash of an archive
10683 containing this output.
10685 When @var{references-graphs} is true, it must be a list of file
10686 name/store path pairs. In that case, the reference graph of each store
10687 path is exported in the build environment in the corresponding file, in
10688 a simple text format.
10690 When @var{allowed-references} is true, it must be a list of store items
10691 or outputs that the derivation's output may refer to. Likewise,
10692 @var{disallowed-references}, if true, must be a list of things the
10693 outputs may @emph{not} refer to.
10695 When @var{leaked-env-vars} is true, it must be a list of strings
10696 denoting environment variables that are allowed to ``leak'' from the
10697 daemon's environment to the build environment. This is only applicable
10698 to fixed-output derivations---i.e., when @var{hash} is true. The main
10699 use is to allow variables such as @code{http_proxy} to be passed to
10700 derivations that download files.
10702 When @var{local-build?} is true, declare that the derivation is not a
10703 good candidate for offloading and should rather be built locally
10704 (@pxref{Daemon Offload Setup}). This is the case for small derivations
10705 where the costs of data transfers would outweigh the benefits.
10707 When @var{substitutable?} is false, declare that substitutes of the
10708 derivation's output should not be used (@pxref{Substitutes}). This is
10709 useful, for instance, when building packages that capture details of the
10710 host CPU instruction set.
10712 @var{properties} must be an association list describing ``properties'' of the
10713 derivation. It is kept as-is, uninterpreted, in the derivation.
10717 Here's an example with a shell script as its builder, assuming
10718 @var{store} is an open connection to the daemon, and @var{bash} points
10719 to a Bash executable in the store:
10722 (use-modules (guix utils)
10724 (guix derivations))
10726 (let ((builder ; add the Bash script to the store
10727 (add-text-to-store store "my-builder.sh"
10728 "echo hello world > $out\n" '())))
10729 (derivation store "foo"
10730 bash `("-e" ,builder)
10731 #:inputs `((,bash) (,builder))
10732 #:env-vars '(("HOME" . "/homeless"))))
10733 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
10736 As can be guessed, this primitive is cumbersome to use directly. A
10737 better approach is to write build scripts in Scheme, of course! The
10738 best course of action for that is to write the build code as a
10739 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
10740 information, @pxref{G-Expressions}.
10742 Once upon a time, @code{gexp->derivation} did not exist and constructing
10743 derivations with build code written in Scheme was achieved with
10744 @code{build-expression->derivation}, documented below. This procedure
10745 is now deprecated in favor of the much nicer @code{gexp->derivation}.
10747 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
10748 @var{name} @var{exp} @
10749 [#:system (%current-system)] [#:inputs '()] @
10750 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10751 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
10752 [#:references-graphs #f] [#:allowed-references #f] @
10753 [#:disallowed-references #f] @
10754 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
10755 Return a derivation that executes Scheme expression @var{exp} as a
10756 builder for derivation @var{name}. @var{inputs} must be a list of
10757 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
10758 @code{"out"} is assumed. @var{modules} is a list of names of Guile
10759 modules from the current search path to be copied in the store,
10760 compiled, and made available in the load path during the execution of
10761 @var{exp}---e.g., @code{((guix build utils) (guix build
10762 gnu-build-system))}.
10764 @var{exp} is evaluated in an environment where @code{%outputs} is bound
10765 to a list of output/path pairs, and where @code{%build-inputs} is bound
10766 to a list of string/output-path pairs made from @var{inputs}.
10767 Optionally, @var{env-vars} is a list of string pairs specifying the name
10768 and value of environment variables visible to the builder. The builder
10769 terminates by passing the result of @var{exp} to @code{exit}; thus, when
10770 @var{exp} returns @code{#f}, the build is considered to have failed.
10772 @var{exp} is built using @var{guile-for-build} (a derivation). When
10773 @var{guile-for-build} is omitted or is @code{#f}, the value of the
10774 @code{%guile-for-build} fluid is used instead.
10776 See the @code{derivation} procedure for the meaning of
10777 @var{references-graphs}, @var{allowed-references},
10778 @var{disallowed-references}, @var{local-build?}, and
10779 @var{substitutable?}.
10783 Here's an example of a single-output derivation that creates a directory
10784 containing one file:
10787 (let ((builder '(let ((out (assoc-ref %outputs "out")))
10788 (mkdir out) ; create /gnu/store/@dots{}-goo
10789 (call-with-output-file (string-append out "/test")
10791 (display '(hello guix) p))))))
10792 (build-expression->derivation store "goo" builder))
10794 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
10798 @node The Store Monad
10799 @section The Store Monad
10803 The procedures that operate on the store described in the previous
10804 sections all take an open connection to the build daemon as their first
10805 argument. Although the underlying model is functional, they either have
10806 side effects or depend on the current state of the store.
10808 The former is inconvenient: the connection to the build daemon has to be
10809 carried around in all those functions, making it impossible to compose
10810 functions that do not take that parameter with functions that do. The
10811 latter can be problematic: since store operations have side effects
10812 and/or depend on external state, they have to be properly sequenced.
10814 @cindex monadic values
10815 @cindex monadic functions
10816 This is where the @code{(guix monads)} module comes in. This module
10817 provides a framework for working with @dfn{monads}, and a particularly
10818 useful monad for our uses, the @dfn{store monad}. Monads are a
10819 construct that allows two things: associating ``context'' with values
10820 (in our case, the context is the store), and building sequences of
10821 computations (here computations include accesses to the store). Values
10822 in a monad---values that carry this additional context---are called
10823 @dfn{monadic values}; procedures that return such values are called
10824 @dfn{monadic procedures}.
10826 Consider this ``normal'' procedure:
10829 (define (sh-symlink store)
10830 ;; Return a derivation that symlinks the 'bash' executable.
10831 (let* ((drv (package-derivation store bash))
10832 (out (derivation->output-path drv))
10833 (sh (string-append out "/bin/bash")))
10834 (build-expression->derivation store "sh"
10835 `(symlink ,sh %output))))
10838 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
10839 as a monadic function:
10842 (define (sh-symlink)
10843 ;; Same, but return a monadic value.
10844 (mlet %store-monad ((drv (package->derivation bash)))
10845 (gexp->derivation "sh"
10846 #~(symlink (string-append #$drv "/bin/bash")
10850 There are several things to note in the second version: the @code{store}
10851 parameter is now implicit and is ``threaded'' in the calls to the
10852 @code{package->derivation} and @code{gexp->derivation} monadic
10853 procedures, and the monadic value returned by @code{package->derivation}
10854 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
10856 As it turns out, the call to @code{package->derivation} can even be
10857 omitted since it will take place implicitly, as we will see later
10858 (@pxref{G-Expressions}):
10861 (define (sh-symlink)
10862 (gexp->derivation "sh"
10863 #~(symlink (string-append #$bash "/bin/bash")
10868 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
10869 @c for the funny quote.
10870 Calling the monadic @code{sh-symlink} has no effect. As someone once
10871 said, ``you exit a monad like you exit a building on fire: by running''.
10872 So, to exit the monad and get the desired effect, one must use
10873 @code{run-with-store}:
10876 (run-with-store (open-connection) (sh-symlink))
10877 @result{} /gnu/store/...-sh-symlink
10880 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
10881 new ``commands'' to make it easier to deal with monadic procedures:
10882 @code{run-in-store}, and @code{enter-store-monad} (@pxref{Using Guix
10883 Interactively}). The former is used
10884 to ``run'' a single monadic value through the store:
10887 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
10888 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10891 The latter enters a recursive REPL, where all the return values are
10892 automatically run through the store:
10895 scheme@@(guile-user)> ,enter-store-monad
10896 store-monad@@(guile-user) [1]> (package->derivation hello)
10897 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10898 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
10899 $3 = "/gnu/store/@dots{}-foo"
10900 store-monad@@(guile-user) [1]> ,q
10901 scheme@@(guile-user)>
10905 Note that non-monadic values cannot be returned in the
10906 @code{store-monad} REPL.
10908 Other meta-commands are available at the REPL, such as @code{,build} to
10909 build a file-like object (@pxref{Using Guix Interactively}).
10911 The main syntactic forms to deal with monads in general are provided by
10912 the @code{(guix monads)} module and are described below.
10914 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
10915 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
10919 @deffn {Scheme Syntax} return @var{val}
10920 Return a monadic value that encapsulates @var{val}.
10923 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
10924 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
10925 procedures @var{mproc}@dots{}@footnote{This operation is commonly
10926 referred to as ``bind'', but that name denotes an unrelated procedure in
10927 Guile. Thus we use this somewhat cryptic symbol inherited from the
10928 Haskell language.}. There can be one @var{mproc} or several of them, as
10933 (with-monad %state-monad
10935 (lambda (x) (return (+ 1 x)))
10936 (lambda (x) (return (* 2 x)))))
10940 @result{} some-state
10944 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
10946 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
10948 Bind the variables @var{var} to the monadic values @var{mval} in
10949 @var{body}, which is a sequence of expressions. As with the bind
10950 operator, this can be thought of as ``unpacking'' the raw, non-monadic
10951 value ``contained'' in @var{mval} and making @var{var} refer to that
10952 raw, non-monadic value within the scope of the @var{body}. The form
10953 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
10954 @var{val}, as per @code{let}. The binding operations occur in sequence
10955 from left to right. The last expression of @var{body} must be a monadic
10956 expression, and its result will become the result of the @code{mlet} or
10957 @code{mlet*} when run in the @var{monad}.
10959 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
10960 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
10963 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
10964 Bind @var{mexp} and the following monadic expressions in sequence,
10965 returning the result of the last expression. Every expression in the
10966 sequence must be a monadic expression.
10968 This is akin to @code{mlet}, except that the return values of the
10969 monadic expressions are ignored. In that sense, it is analogous to
10970 @code{begin}, but applied to monadic expressions.
10973 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
10974 When @var{condition} is true, evaluate the sequence of monadic
10975 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
10976 @var{condition} is false, return @code{*unspecified*} in the current
10977 monad. Every expression in the sequence must be a monadic expression.
10980 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
10981 When @var{condition} is false, evaluate the sequence of monadic
10982 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
10983 @var{condition} is true, return @code{*unspecified*} in the current
10984 monad. Every expression in the sequence must be a monadic expression.
10987 @cindex state monad
10988 The @code{(guix monads)} module provides the @dfn{state monad}, which
10989 allows an additional value---the state---to be @emph{threaded} through
10990 monadic procedure calls.
10992 @defvr {Scheme Variable} %state-monad
10993 The state monad. Procedures in the state monad can access and change
10994 the state that is threaded.
10996 Consider the example below. The @code{square} procedure returns a value
10997 in the state monad. It returns the square of its argument, but also
10998 increments the current state value:
11002 (mlet %state-monad ((count (current-state)))
11003 (mbegin %state-monad
11004 (set-current-state (+ 1 count))
11005 (return (* x x)))))
11007 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
11012 When ``run'' through @code{%state-monad}, we obtain that additional state
11013 value, which is the number of @code{square} calls.
11016 @deffn {Monadic Procedure} current-state
11017 Return the current state as a monadic value.
11020 @deffn {Monadic Procedure} set-current-state @var{value}
11021 Set the current state to @var{value} and return the previous state as a
11025 @deffn {Monadic Procedure} state-push @var{value}
11026 Push @var{value} to the current state, which is assumed to be a list,
11027 and return the previous state as a monadic value.
11030 @deffn {Monadic Procedure} state-pop
11031 Pop a value from the current state and return it as a monadic value.
11032 The state is assumed to be a list.
11035 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
11036 Run monadic value @var{mval} starting with @var{state} as the initial
11037 state. Return two values: the resulting value, and the resulting state.
11040 The main interface to the store monad, provided by the @code{(guix
11041 store)} module, is as follows.
11043 @defvr {Scheme Variable} %store-monad
11044 The store monad---an alias for @code{%state-monad}.
11046 Values in the store monad encapsulate accesses to the store. When its
11047 effect is needed, a value of the store monad must be ``evaluated'' by
11048 passing it to the @code{run-with-store} procedure (see below).
11051 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
11052 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
11053 open store connection.
11056 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
11057 Return as a monadic value the absolute file name in the store of the file
11058 containing @var{text}, a string. @var{references} is a list of store items that the
11059 resulting text file refers to; it defaults to the empty list.
11062 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
11063 Return as a monadic value the absolute file name in the store of the file
11064 containing @var{data}, a bytevector. @var{references} is a list of store
11065 items that the resulting binary file refers to; it defaults to the empty list.
11068 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
11069 [#:recursive? #t] [#:select? (const #t)]
11070 Return the name of @var{file} once interned in the store. Use
11071 @var{name} as its store name, or the basename of @var{file} if
11072 @var{name} is omitted.
11074 When @var{recursive?} is true, the contents of @var{file} are added
11075 recursively; if @var{file} designates a flat file and @var{recursive?}
11076 is true, its contents are added, and its permission bits are kept.
11078 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11079 @var{stat})} for each directory entry, where @var{file} is the entry's
11080 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11081 entries for which @var{select?} does not return true.
11083 The example below adds a file to the store, under two different names:
11086 (run-with-store (open-connection)
11087 (mlet %store-monad ((a (interned-file "README"))
11088 (b (interned-file "README" "LEGU-MIN")))
11089 (return (list a b))))
11091 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
11096 The @code{(guix packages)} module exports the following package-related
11097 monadic procedures:
11099 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
11100 [#:system (%current-system)] [#:target #f] @
11102 Return as a monadic
11103 value in the absolute file name of @var{file} within the @var{output}
11104 directory of @var{package}. When @var{file} is omitted, return the name
11105 of the @var{output} directory of @var{package}. When @var{target} is
11106 true, use it as a cross-compilation target triplet.
11108 Note that this procedure does @emph{not} build @var{package}. Thus, the
11109 result might or might not designate an existing file. We recommend not
11110 using this procedure unless you know what you are doing.
11113 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
11114 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
11115 @var{target} [@var{system}]
11116 Monadic version of @code{package-derivation} and
11117 @code{package-cross-derivation} (@pxref{Defining Packages}).
11121 @node G-Expressions
11122 @section G-Expressions
11124 @cindex G-expression
11125 @cindex build code quoting
11126 So we have ``derivations'', which represent a sequence of build actions
11127 to be performed to produce an item in the store (@pxref{Derivations}).
11128 These build actions are performed when asking the daemon to actually
11129 build the derivations; they are run by the daemon in a container
11130 (@pxref{Invoking guix-daemon}).
11132 @cindex code staging
11133 @cindex staging, of code
11134 @cindex strata of code
11135 It should come as no surprise that we like to write these build actions
11136 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
11137 code@footnote{The term @dfn{stratum} in this context was coined by
11138 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
11139 Kiselyov, who has written insightful
11140 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
11141 on this topic}, refers to this kind of code generation as
11142 @dfn{staging}.}: the ``host code''---code that defines packages, talks
11143 to the daemon, etc.---and the ``build code''---code that actually
11144 performs build actions, such as making directories, invoking
11145 @command{make}, and so on (@pxref{Build Phases}).
11147 To describe a derivation and its build actions, one typically needs to
11148 embed build code inside host code. It boils down to manipulating build
11149 code as data, and the homoiconicity of Scheme---code has a direct
11150 representation as data---comes in handy for that. But we need more than
11151 the normal @code{quasiquote} mechanism in Scheme to construct build
11154 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
11155 S-expressions adapted to build expressions. G-expressions, or
11156 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
11157 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
11158 @code{#$}, and @code{#$@@}), which are comparable to
11159 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
11160 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
11161 GNU Guile Reference Manual}). However, there are major differences:
11165 Gexps are meant to be written to a file and run or manipulated by other
11169 When a high-level object such as a package or derivation is unquoted
11170 inside a gexp, the result is as if its output file name had been
11174 Gexps carry information about the packages or derivations they refer to,
11175 and these dependencies are automatically added as inputs to the build
11176 processes that use them.
11179 @cindex lowering, of high-level objects in gexps
11180 This mechanism is not limited to package and derivation
11181 objects: @dfn{compilers} able to ``lower'' other high-level objects to
11182 derivations or files in the store can be defined,
11183 such that these objects can also be inserted
11184 into gexps. For example, a useful type of high-level objects that can be
11185 inserted in a gexp is ``file-like objects'', which make it easy to
11186 add files to the store and to refer to them in
11187 derivations and such (see @code{local-file} and @code{plain-file}
11190 To illustrate the idea, here is an example of a gexp:
11197 (symlink (string-append #$coreutils "/bin/ls")
11201 This gexp can be passed to @code{gexp->derivation}; we obtain a
11202 derivation that builds a directory containing exactly one symlink to
11203 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
11206 (gexp->derivation "the-thing" build-exp)
11209 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
11210 substituted to the reference to the @var{coreutils} package in the
11211 actual build code, and @var{coreutils} is automatically made an input to
11212 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
11213 output)}) is replaced by a string containing the directory name of the
11214 output of the derivation.
11216 @cindex cross compilation
11217 In a cross-compilation context, it is useful to distinguish between
11218 references to the @emph{native} build of a package---that can run on the
11219 host---versus references to cross builds of a package. To that end, the
11220 @code{#+} plays the same role as @code{#$}, but is a reference to a
11221 native package build:
11224 (gexp->derivation "vi"
11227 (mkdir (string-append #$output "/bin"))
11228 (system* (string-append #+coreutils "/bin/ln")
11230 (string-append #$emacs "/bin/emacs")
11231 (string-append #$output "/bin/vi")))
11232 #:target "aarch64-linux-gnu")
11236 In the example above, the native build of @var{coreutils} is used, so
11237 that @command{ln} can actually run on the host; but then the
11238 cross-compiled build of @var{emacs} is referenced.
11240 @cindex imported modules, for gexps
11241 @findex with-imported-modules
11242 Another gexp feature is @dfn{imported modules}: sometimes you want to be
11243 able to use certain Guile modules from the ``host environment'' in the
11244 gexp, so those modules should be imported in the ``build environment''.
11245 The @code{with-imported-modules} form allows you to express that:
11248 (let ((build (with-imported-modules '((guix build utils))
11250 (use-modules (guix build utils))
11251 (mkdir-p (string-append #$output "/bin"))))))
11252 (gexp->derivation "empty-dir"
11255 (display "success!\n")
11260 In this example, the @code{(guix build utils)} module is automatically
11261 pulled into the isolated build environment of our gexp, such that
11262 @code{(use-modules (guix build utils))} works as expected.
11264 @cindex module closure
11265 @findex source-module-closure
11266 Usually you want the @emph{closure} of the module to be imported---i.e.,
11267 the module itself and all the modules it depends on---rather than just
11268 the module; failing to do that, attempts to use the module will fail
11269 because of missing dependent modules. The @code{source-module-closure}
11270 procedure computes the closure of a module by looking at its source file
11271 headers, which comes in handy in this case:
11274 (use-modules (guix modules)) ;for 'source-module-closure'
11276 (with-imported-modules (source-module-closure
11277 '((guix build utils)
11278 (gnu build image)))
11279 (gexp->derivation "something-with-vms"
11281 (use-modules (guix build utils)
11286 @cindex extensions, for gexps
11287 @findex with-extensions
11288 In the same vein, sometimes you want to import not just pure-Scheme
11289 modules, but also ``extensions'' such as Guile bindings to C libraries
11290 or other ``full-blown'' packages. Say you need the @code{guile-json}
11291 package available on the build side, here's how you would do it:
11294 (use-modules (gnu packages guile)) ;for 'guile-json'
11296 (with-extensions (list guile-json)
11297 (gexp->derivation "something-with-json"
11299 (use-modules (json))
11303 The syntactic form to construct gexps is summarized below.
11305 @deffn {Scheme Syntax} #~@var{exp}
11306 @deffnx {Scheme Syntax} (gexp @var{exp})
11307 Return a G-expression containing @var{exp}. @var{exp} may contain one
11308 or more of the following forms:
11312 @itemx (ungexp @var{obj})
11313 Introduce a reference to @var{obj}. @var{obj} may have one of the
11314 supported types, for example a package or a
11315 derivation, in which case the @code{ungexp} form is replaced by its
11316 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
11318 If @var{obj} is a list, it is traversed and references to supported
11319 objects are substituted similarly.
11321 If @var{obj} is another gexp, its contents are inserted and its
11322 dependencies are added to those of the containing gexp.
11324 If @var{obj} is another kind of object, it is inserted as is.
11326 @item #$@var{obj}:@var{output}
11327 @itemx (ungexp @var{obj} @var{output})
11328 This is like the form above, but referring explicitly to the
11329 @var{output} of @var{obj}---this is useful when @var{obj} produces
11330 multiple outputs (@pxref{Packages with Multiple Outputs}).
11333 @itemx #+@var{obj}:output
11334 @itemx (ungexp-native @var{obj})
11335 @itemx (ungexp-native @var{obj} @var{output})
11336 Same as @code{ungexp}, but produces a reference to the @emph{native}
11337 build of @var{obj} when used in a cross compilation context.
11339 @item #$output[:@var{output}]
11340 @itemx (ungexp output [@var{output}])
11341 Insert a reference to derivation output @var{output}, or to the main
11342 output when @var{output} is omitted.
11344 This only makes sense for gexps passed to @code{gexp->derivation}.
11346 @item #$@@@var{lst}
11347 @itemx (ungexp-splicing @var{lst})
11348 Like the above, but splices the contents of @var{lst} inside the
11351 @item #+@@@var{lst}
11352 @itemx (ungexp-native-splicing @var{lst})
11353 Like the above, but refers to native builds of the objects listed in
11358 G-expressions created by @code{gexp} or @code{#~} are run-time objects
11359 of the @code{gexp?} type (see below).
11362 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
11363 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
11364 in their execution environment.
11366 Each item in @var{modules} can be the name of a module, such as
11367 @code{(guix build utils)}, or it can be a module name, followed by an
11368 arrow, followed by a file-like object:
11371 `((guix build utils)
11373 ((guix config) => ,(scheme-file "config.scm"
11374 #~(define-module @dots{}))))
11378 In the example above, the first two modules are taken from the search
11379 path, and the last one is created from the given file-like object.
11381 This form has @emph{lexical} scope: it has an effect on the gexps
11382 directly defined in @var{body}@dots{}, but not on those defined, say, in
11383 procedures called from @var{body}@dots{}.
11386 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
11387 Mark the gexps defined in @var{body}@dots{} as requiring
11388 @var{extensions} in their build and execution environment.
11389 @var{extensions} is typically a list of package objects such as those
11390 defined in the @code{(gnu packages guile)} module.
11392 Concretely, the packages listed in @var{extensions} are added to the
11393 load path while compiling imported modules in @var{body}@dots{}; they
11394 are also added to the load path of the gexp returned by
11398 @deffn {Scheme Procedure} gexp? @var{obj}
11399 Return @code{#t} if @var{obj} is a G-expression.
11402 G-expressions are meant to be written to disk, either as code building
11403 some derivation, or as plain files in the store. The monadic procedures
11404 below allow you to do that (@pxref{The Store Monad}, for more
11405 information about monads).
11407 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
11408 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
11409 [#:hash #f] [#:hash-algo #f] @
11410 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
11411 [#:module-path @code{%load-path}] @
11412 [#:effective-version "2.2"] @
11413 [#:references-graphs #f] [#:allowed-references #f] @
11414 [#:disallowed-references #f] @
11415 [#:leaked-env-vars #f] @
11416 [#:script-name (string-append @var{name} "-builder")] @
11417 [#:deprecation-warnings #f] @
11418 [#:local-build? #f] [#:substitutable? #t] @
11419 [#:properties '()] [#:guile-for-build #f]
11420 Return a derivation @var{name} that runs @var{exp} (a gexp) with
11421 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
11422 stored in a file called @var{script-name}. When @var{target} is true,
11423 it is used as the cross-compilation target triplet for packages referred
11426 @var{modules} is deprecated in favor of @code{with-imported-modules}.
11428 make @var{modules} available in the evaluation context of @var{exp};
11429 @var{modules} is a list of names of Guile modules searched in
11430 @var{module-path} to be copied in the store, compiled, and made available in
11431 the load path during the execution of @var{exp}---e.g., @code{((guix
11432 build utils) (guix build gnu-build-system))}.
11434 @var{effective-version} determines the string to use when adding extensions of
11435 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
11437 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
11440 When @var{references-graphs} is true, it must be a list of tuples of one of the
11444 (@var{file-name} @var{package})
11445 (@var{file-name} @var{package} @var{output})
11446 (@var{file-name} @var{derivation})
11447 (@var{file-name} @var{derivation} @var{output})
11448 (@var{file-name} @var{store-item})
11451 The right-hand-side of each element of @var{references-graphs} is automatically made
11452 an input of the build process of @var{exp}. In the build environment, each
11453 @var{file-name} contains the reference graph of the corresponding item, in a simple
11456 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
11457 In the latter case, the list denotes store items that the result is allowed to
11458 refer to. Any reference to another store item will lead to a build error.
11459 Similarly for @var{disallowed-references}, which can list items that must not be
11460 referenced by the outputs.
11462 @var{deprecation-warnings} determines whether to show deprecation warnings while
11463 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
11465 The other arguments are as for @code{derivation} (@pxref{Derivations}).
11468 @cindex file-like objects
11469 The @code{local-file}, @code{plain-file}, @code{computed-file},
11470 @code{program-file}, and @code{scheme-file} procedures below return
11471 @dfn{file-like objects}. That is, when unquoted in a G-expression,
11472 these objects lead to a file in the store. Consider this G-expression:
11475 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
11476 #$(local-file "/tmp/my-nscd.conf"))
11479 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
11480 to the store. Once expanded, for instance @i{via}
11481 @code{gexp->derivation}, the G-expression refers to that copy under
11482 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
11483 does not have any effect on what the G-expression does.
11484 @code{plain-file} can be used similarly; it differs in that the file
11485 content is directly passed as a string.
11487 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
11488 [#:recursive? #f] [#:select? (const #t)]
11489 Return an object representing local file @var{file} to add to the store;
11490 this object can be used in a gexp. If @var{file} is a literal string
11491 denoting a relative file name, it is looked up relative to the source
11492 file where it appears; if @var{file} is not a literal string, it is
11493 looked up relative to the current working directory at run time.
11494 @var{file} will be added to the store under @var{name}--by default the
11495 base name of @var{file}.
11497 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
11498 designates a flat file and @var{recursive?} is true, its contents are added, and its
11499 permission bits are kept.
11501 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11502 @var{stat})} for each directory entry, where @var{file} is the entry's
11503 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11504 entries for which @var{select?} does not return true.
11506 This is the declarative counterpart of the @code{interned-file} monadic
11507 procedure (@pxref{The Store Monad, @code{interned-file}}).
11510 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
11511 Return an object representing a text file called @var{name} with the given
11512 @var{content} (a string or a bytevector) to be added to the store.
11514 This is the declarative counterpart of @code{text-file}.
11517 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
11518 [#:local-build? #t]
11520 Return an object representing the store item @var{name}, a file or
11521 directory computed by @var{gexp}. When @var{local-build?} is true (the
11522 default), the derivation is built locally. @var{options} is a list of
11523 additional arguments to pass to @code{gexp->derivation}.
11525 This is the declarative counterpart of @code{gexp->derivation}.
11528 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
11529 [#:guile (default-guile)] [#:module-path %load-path] @
11530 [#:system (%current-system)] [#:target #f]
11531 Return an executable script @var{name} that runs @var{exp} using
11532 @var{guile}, with @var{exp}'s imported modules in its search path.
11533 Look up @var{exp}'s modules in @var{module-path}.
11535 The example below builds a script that simply invokes the @command{ls}
11539 (use-modules (guix gexp) (gnu packages base))
11541 (gexp->script "list-files"
11542 #~(execl #$(file-append coreutils "/bin/ls")
11546 When ``running'' it through the store (@pxref{The Store Monad,
11547 @code{run-with-store}}), we obtain a derivation that produces an
11548 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
11551 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
11553 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
11557 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
11558 [#:guile #f] [#:module-path %load-path]
11559 Return an object representing the executable store item @var{name} that
11560 runs @var{gexp}. @var{guile} is the Guile package used to execute that
11561 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
11563 This is the declarative counterpart of @code{gexp->script}.
11566 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
11567 [#:set-load-path? #t] [#:module-path %load-path] @
11569 [#:guile (default-guile)]
11570 Return a derivation that builds a file @var{name} containing @var{exp}.
11571 When @var{splice?} is true, @var{exp} is considered to be a list of
11572 expressions that will be spliced in the resulting file.
11574 When @var{set-load-path?} is true, emit code in the resulting file to
11575 set @code{%load-path} and @code{%load-compiled-path} to honor
11576 @var{exp}'s imported modules. Look up @var{exp}'s modules in
11579 The resulting file holds references to all the dependencies of @var{exp}
11580 or a subset thereof.
11583 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
11584 [#:splice? #f] [#:set-load-path? #t]
11585 Return an object representing the Scheme file @var{name} that contains
11588 This is the declarative counterpart of @code{gexp->file}.
11591 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
11592 Return as a monadic value a derivation that builds a text file
11593 containing all of @var{text}. @var{text} may list, in addition to
11594 strings, objects of any type that can be used in a gexp: packages,
11595 derivations, local file objects, etc. The resulting store file holds
11596 references to all these.
11598 This variant should be preferred over @code{text-file} anytime the file
11599 to create will reference items from the store. This is typically the
11600 case when building a configuration file that embeds store file names,
11604 (define (profile.sh)
11605 ;; Return the name of a shell script in the store that
11606 ;; initializes the 'PATH' environment variable.
11607 (text-file* "profile.sh"
11608 "export PATH=" coreutils "/bin:"
11609 grep "/bin:" sed "/bin\n"))
11612 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
11613 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
11614 preventing them from being garbage-collected during its lifetime.
11617 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
11618 Return an object representing store file @var{name} containing
11619 @var{text}. @var{text} is a sequence of strings and file-like objects,
11623 (mixed-text-file "profile"
11624 "export PATH=" coreutils "/bin:" grep "/bin")
11627 This is the declarative counterpart of @code{text-file*}.
11630 @deffn {Scheme Procedure} file-union @var{name} @var{files}
11631 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
11632 Each item in @var{files} must be a two-element list where the first element is the
11633 file name to use in the new directory, and the second element is a gexp
11634 denoting the target file. Here's an example:
11638 `(("hosts" ,(plain-file "hosts"
11639 "127.0.0.1 localhost"))
11640 ("bashrc" ,(plain-file "bashrc"
11641 "alias ls='ls --color=auto'"))))
11644 This yields an @code{etc} directory containing these two files.
11647 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
11648 Return a directory that is the union of @var{things}, where @var{things} is a list of
11649 file-like objects denoting directories. For example:
11652 (directory-union "guile+emacs" (list guile emacs))
11655 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
11658 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
11659 Return a file-like object that expands to the concatenation of @var{obj}
11660 and @var{suffix}, where @var{obj} is a lowerable object and each
11661 @var{suffix} is a string.
11663 As an example, consider this gexp:
11666 (gexp->script "run-uname"
11667 #~(system* #$(file-append coreutils
11671 The same effect could be achieved with:
11674 (gexp->script "run-uname"
11675 #~(system* (string-append #$coreutils
11679 There is one difference though: in the @code{file-append} case, the
11680 resulting script contains the absolute file name as a string, whereas in
11681 the second case, the resulting script contains a @code{(string-append
11682 @dots{})} expression to construct the file name @emph{at run time}.
11685 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
11686 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
11687 Bind @var{system} to the currently targeted system---e.g.,
11688 @code{"x86_64-linux"}---within @var{body}.
11690 In the second case, additionally bind @var{target} to the current
11691 cross-compilation target---a GNU triplet such as
11692 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
11695 @code{let-system} is useful in the occasional case where the object
11696 spliced into the gexp depends on the target system, as in this example:
11700 #+(let-system system
11701 (cond ((string-prefix? "armhf-" system)
11702 (file-append qemu "/bin/qemu-system-arm"))
11703 ((string-prefix? "x86_64-" system)
11704 (file-append qemu "/bin/qemu-system-x86_64"))
11706 (error "dunno!"))))
11707 "-net" "user" #$image)
11711 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
11712 This macro is similar to the @code{parameterize} form for
11713 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
11714 Guile Reference Manual}). The key difference is that it takes effect
11715 when the file-like object returned by @var{exp} is lowered to a
11716 derivation or store item.
11718 A typical use of @code{with-parameters} is to force the system in effect
11719 for a given object:
11722 (with-parameters ((%current-system "i686-linux"))
11726 The example above returns an object that corresponds to the i686 build
11727 of Coreutils, regardless of the current value of @code{%current-system}.
11731 Of course, in addition to gexps embedded in ``host'' code, there are
11732 also modules containing build tools. To make it clear that they are
11733 meant to be used in the build stratum, these modules are kept in the
11734 @code{(guix build @dots{})} name space.
11736 @cindex lowering, of high-level objects in gexps
11737 Internally, high-level objects are @dfn{lowered}, using their compiler,
11738 to either derivations or store items. For instance, lowering a package
11739 yields a derivation, and lowering a @code{plain-file} yields a store
11740 item. This is achieved using the @code{lower-object} monadic procedure.
11742 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
11744 Return as a value in @code{%store-monad} the derivation or store item
11745 corresponding to @var{obj} for @var{system}, cross-compiling for
11746 @var{target} if @var{target} is true. @var{obj} must be an object that
11747 has an associated gexp compiler, such as a @code{<package>}.
11750 @deffn {Procedure} gexp->approximate-sexp @var{gexp}
11751 Sometimes, it may be useful to convert a G-exp into a S-exp. For
11752 example, some linters (@pxref{Invoking guix lint}) peek into the build
11753 phases of a package to detect potential problems. This conversion can
11754 be achieved with this procedure. However, some information can be lost
11755 in the process. More specifically, lowerable objects will be silently
11756 replaced with some arbitrary object -- currently the list
11757 @code{(*approximate*)}, but this may change.
11760 @node Invoking guix repl
11761 @section Invoking @command{guix repl}
11763 @cindex REPL, read-eval-print loop, script
11764 The @command{guix repl} command makes it easier to program Guix in Guile
11765 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
11766 programming (@pxref{Using Guile Interactively,,, guile,
11767 GNU Guile Reference Manual}), or by running Guile scripts
11768 (@pxref{Running Guile Scripts,,, guile,
11769 GNU Guile Reference Manual}).
11770 Compared to just launching the @command{guile}
11771 command, @command{guix repl} guarantees that all the Guix modules and all its
11772 dependencies are available in the search path.
11774 The general syntax is:
11777 guix repl @var{options} [@var{file} @var{args}]
11780 When a @var{file} argument is provided, @var{file} is
11781 executed as a Guile scripts:
11784 guix repl my-script.scm
11787 To pass arguments to the script, use @code{--} to prevent them from
11788 being interpreted as arguments to @command{guix repl} itself:
11791 guix repl -- my-script.scm --input=foo.txt
11794 To make a script executable directly from the shell, using the guix
11795 executable that is on the user's search path, add the following two
11796 lines at the top of the script:
11799 @code{#!/usr/bin/env -S guix repl --}
11803 Without a file name argument, a Guile REPL is started, allowing for
11804 interactive use (@pxref{Using Guix Interactively}):
11808 scheme@@(guile-user)> ,use (gnu packages base)
11809 scheme@@(guile-user)> coreutils
11810 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
11814 In addition, @command{guix repl} implements a simple machine-readable REPL
11815 protocol for use by @code{(guix inferior)}, a facility to interact with
11816 @dfn{inferiors}, separate processes running a potentially different revision
11819 The available options are as follows:
11822 @item --type=@var{type}
11823 @itemx -t @var{type}
11824 Start a REPL of the given @var{TYPE}, which can be one of the following:
11828 This is default, and it spawns a standard full-featured Guile REPL.
11830 Spawn a REPL that uses the machine-readable protocol. This is the protocol
11831 that the @code{(guix inferior)} module speaks.
11834 @item --listen=@var{endpoint}
11835 By default, @command{guix repl} reads from standard input and writes to
11836 standard output. When this option is passed, it will instead listen for
11837 connections on @var{endpoint}. Here are examples of valid options:
11840 @item --listen=tcp:37146
11841 Accept connections on localhost on port 37146.
11843 @item --listen=unix:/tmp/socket
11844 Accept connections on the Unix-domain socket @file{/tmp/socket}.
11847 @item --load-path=@var{directory}
11848 @itemx -L @var{directory}
11849 Add @var{directory} to the front of the package module search path
11850 (@pxref{Package Modules}).
11852 This allows users to define their own packages and make them visible to
11853 the script or REPL.
11856 Inhibit loading of the @file{~/.guile} file. By default, that
11857 configuration file is loaded when spawning a @code{guile} REPL.
11860 @node Using Guix Interactively
11861 @section Using Guix Interactively
11863 @cindex interactive use
11864 @cindex REPL, read-eval-print loop
11865 The @command{guix repl} command gives you access to a warm and friendly
11866 @dfn{read-eval-print loop} (REPL) (@pxref{Invoking guix repl}). If
11867 you're getting into Guix programming---defining your own packages,
11868 writing manifests, defining services for Guix System or Guix Home,
11869 etc.---you will surely find it convenient to toy with ideas at the REPL.
11871 If you use Emacs, the most convenient way to do that is with Geiser
11872 (@pxref{The Perfect Setup}), but you do not have to use Emacs to enjoy
11873 the REPL@. When using @command{guix repl} or @command{guile} in the
11874 terminal, we recommend using Readline for completion and Colorized to
11875 get colorful output. To do that, you can run:
11878 guix install guile guile-readline guile-colorized
11882 ... and then create a @file{.guile} file in your home directory containing
11886 (use-modules (ice-9 readline) (ice-9 colorized))
11888 (activate-readline)
11889 (activate-colorized)
11892 The REPL lets you evaluate Scheme code; you type a Scheme expression at
11893 the prompt, and the REPL prints what it evaluates to:
11897 scheme@@(guix-user)> (+ 2 3)
11899 scheme@@(guix-user)> (string-append "a" "b")
11903 It becomes interesting when you start fiddling with Guix at the REPL.
11904 The first thing you'll want to do is to ``import'' the @code{(guix)}
11905 module, which gives access to the main part of the programming
11906 interface, and perhaps a bunch of useful Guix modules. You could type
11907 @code{(use-modules (guix))}, which is valid Scheme code to import a
11908 module (@pxref{Using Guile Modules,,, guile, GNU Guile Reference
11909 Manual}), but the REPL provides the @code{use} @dfn{command} as a
11910 shorthand notation (@pxref{REPL Commands,,, guile, GNU Guile Reference
11914 scheme@@(guix-user)> ,use (guix)
11915 scheme@@(guix-user)> ,use (gnu packages base)
11918 Notice that REPL commands are introduced by a leading comma. A REPL
11919 command like @code{use} is not valid Scheme code; it's interpreted
11920 specially by the REPL.
11922 Guix extends the Guile REPL with additional commands for convenience.
11923 Among those, the @code{build} command comes in handy: it ensures that
11924 the given file-like object is built, building it if needed, and returns
11925 its output file name(s). In the example below, we build the
11926 @code{coreutils} and @code{grep} packages, as well as a ``computed
11927 file'' (@pxref{G-Expressions, @code{computed-file}}), and we use the
11928 @code{scandir} procedure to list the files in Grep's @code{/bin}
11932 scheme@@(guix-user)> ,build coreutils
11933 $1 = "/gnu/store/@dots{}-coreutils-8.32-debug"
11934 $2 = "/gnu/store/@dots{}-coreutils-8.32"
11935 scheme@@(guix-user)> ,build grep
11936 $3 = "/gnu/store/@dots{}-grep-3.6"
11937 scheme@@(guix-user)> ,build (computed-file "x" #~(mkdir #$output))
11938 building /gnu/store/@dots{}-x.drv...
11939 $4 = "/gnu/store/@dots{}-x"
11940 scheme@@(guix-user)> ,use(ice-9 ftw)
11941 scheme@@(guix-user)> (scandir (string-append $3 "/bin"))
11942 $5 = ("." ".." "egrep" "fgrep" "grep")
11945 At a lower-level, a useful command is @code{lower}: it takes a file-like
11946 object and ``lowers'' it into a derivation (@pxref{Derivations}) or a
11950 scheme@@(guix-user)> ,lower grep
11951 $6 = #<derivation /gnu/store/@dots{}-grep-3.6.drv => /gnu/store/@dots{}-grep-3.6 7f0e639115f0>
11952 scheme@@(guix-user)> ,lower (plain-file "x" "Hello!")
11953 $7 = "/gnu/store/@dots{}-x"
11956 The full list of REPL commands can be seen by typing @code{,help guix}
11957 and is given below for reference.
11959 @deffn {REPL command} build @var{object}
11960 Lower @var{object} and build it if it's not already built, returning its
11961 output file name(s).
11964 @deffn {REPL command} lower @var{object}
11965 Lower @var{object} into a derivation or store file name and return it.
11968 @deffn {REPL command} verbosity @var{level}
11969 Change build verbosity to @var{level}.
11971 This is similar to the @option{--verbosity} command-line option
11972 (@pxref{Common Build Options}): level 0 means total silence, level 1
11973 shows build events only, and higher levels print build logs.
11976 @deffn {REPL command} run-in-store @var{exp}
11977 Run @var{exp}, a monadic expresssion, through the store monad.
11978 @xref{The Store Monad}, for more information.
11981 @deffn {REPL command} enter-store-monad
11982 Enter a new REPL to evaluate monadic expressions (@pxref{The Store
11983 Monad}). You can quit this ``inner'' REPL by typing @code{,q}.
11986 @c *********************************************************************
11990 This section describes Guix command-line utilities. Some of them are
11991 primarily targeted at developers and users who write new package
11992 definitions, while others are more generally useful. They complement
11993 the Scheme programming interface of Guix in a convenient way.
11996 * Invoking guix build:: Building packages from the command line.
11997 * Invoking guix edit:: Editing package definitions.
11998 * Invoking guix download:: Downloading a file and printing its hash.
11999 * Invoking guix hash:: Computing the cryptographic hash of a file.
12000 * Invoking guix import:: Importing package definitions.
12001 * Invoking guix refresh:: Updating package definitions.
12002 * Invoking guix style:: Styling package definitions.
12003 * Invoking guix lint:: Finding errors in package definitions.
12004 * Invoking guix size:: Profiling disk usage.
12005 * Invoking guix graph:: Visualizing the graph of packages.
12006 * Invoking guix publish:: Sharing substitutes.
12007 * Invoking guix challenge:: Challenging substitute servers.
12008 * Invoking guix copy:: Copying to and from a remote store.
12009 * Invoking guix container:: Process isolation.
12010 * Invoking guix weather:: Assessing substitute availability.
12011 * Invoking guix processes:: Listing client processes.
12014 @node Invoking guix build
12015 @section Invoking @command{guix build}
12017 @cindex package building
12018 @cindex @command{guix build}
12019 The @command{guix build} command builds packages or derivations and
12020 their dependencies, and prints the resulting store paths. Note that it
12021 does not modify the user's profile---this is the job of the
12022 @command{guix package} command (@pxref{Invoking guix package}). Thus,
12023 it is mainly useful for distribution developers.
12025 The general syntax is:
12028 guix build @var{options} @var{package-or-derivation}@dots{}
12031 As an example, the following command builds the latest versions of Emacs
12032 and of Guile, displays their build logs, and finally displays the
12033 resulting directories:
12036 guix build emacs guile
12039 Similarly, the following command builds all the available packages:
12042 guix build --quiet --keep-going \
12043 $(guix package -A | awk '@{ print $1 "@@" $2 @}')
12046 @var{package-or-derivation} may be either the name of a package found in
12047 the software distribution such as @code{coreutils} or
12048 @code{coreutils@@8.20}, or a derivation such as
12049 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
12050 package with the corresponding name (and optionally version) is searched
12051 for among the GNU distribution modules (@pxref{Package Modules}).
12053 Alternatively, the @option{--expression} option may be used to specify a
12054 Scheme expression that evaluates to a package; this is useful when
12055 disambiguating among several same-named packages or package variants is
12058 There may be zero or more @var{options}. The available options are
12059 described in the subsections below.
12062 * Common Build Options:: Build options for most commands.
12063 * Package Transformation Options:: Creating variants of packages.
12064 * Additional Build Options:: Options specific to 'guix build'.
12065 * Debugging Build Failures:: Real life packaging experience.
12068 @node Common Build Options
12069 @subsection Common Build Options
12071 A number of options that control the build process are common to
12072 @command{guix build} and other commands that can spawn builds, such as
12073 @command{guix package} or @command{guix archive}. These are the
12078 @item --load-path=@var{directory}
12079 @itemx -L @var{directory}
12080 Add @var{directory} to the front of the package module search path
12081 (@pxref{Package Modules}).
12083 This allows users to define their own packages and make them visible to
12084 the command-line tools.
12086 @item --keep-failed
12088 Keep the build tree of failed builds. Thus, if a build fails, its build
12089 tree is kept under @file{/tmp}, in a directory whose name is shown at
12090 the end of the build log. This is useful when debugging build issues.
12091 @xref{Debugging Build Failures}, for tips and tricks on how to debug
12094 This option implies @option{--no-offload}, and it has no effect when
12095 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
12096 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
12100 Keep going when some of the derivations fail to build; return only once
12101 all the builds have either completed or failed.
12103 The default behavior is to stop as soon as one of the specified
12104 derivations has failed.
12108 Do not build the derivations.
12110 @anchor{fallback-option}
12112 When substituting a pre-built binary fails, fall back to building
12113 packages locally (@pxref{Substitution Failure}).
12115 @item --substitute-urls=@var{urls}
12116 @anchor{client-substitute-urls}
12117 Consider @var{urls} the whitespace-separated list of substitute source
12118 URLs, overriding the default list of URLs of @command{guix-daemon}
12119 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
12121 This means that substitutes may be downloaded from @var{urls}, provided
12122 they are signed by a key authorized by the system administrator
12123 (@pxref{Substitutes}).
12125 When @var{urls} is the empty string, substitutes are effectively
12128 @item --no-substitutes
12129 Do not use substitutes for build products. That is, always build things
12130 locally instead of allowing downloads of pre-built binaries
12131 (@pxref{Substitutes}).
12134 Do not ``graft'' packages. In practice, this means that package updates
12135 available as grafts are not applied. @xref{Security Updates}, for more
12136 information on grafts.
12138 @item --rounds=@var{n}
12139 Build each derivation @var{n} times in a row, and raise an error if
12140 consecutive build results are not bit-for-bit identical.
12142 This is a useful way to detect non-deterministic builds processes.
12143 Non-deterministic build processes are a problem because they make it
12144 practically impossible for users to @emph{verify} whether third-party
12145 binaries are genuine. @xref{Invoking guix challenge}, for more.
12147 When used in conjunction with @option{--keep-failed}, the differing
12148 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12149 This makes it easy to look for differences between the two results.
12152 Do not use offload builds to other machines (@pxref{Daemon Offload
12153 Setup}). That is, always build things locally instead of offloading
12154 builds to remote machines.
12156 @item --max-silent-time=@var{seconds}
12157 When the build or substitution process remains silent for more than
12158 @var{seconds}, terminate it and report a build failure.
12160 By default, the daemon's setting is honored (@pxref{Invoking
12161 guix-daemon, @option{--max-silent-time}}).
12163 @item --timeout=@var{seconds}
12164 Likewise, when the build or substitution process lasts for more than
12165 @var{seconds}, terminate it and report a build failure.
12167 By default, the daemon's setting is honored (@pxref{Invoking
12168 guix-daemon, @option{--timeout}}).
12170 @c Note: This option is actually not part of %standard-build-options but
12171 @c most programs honor it.
12172 @cindex verbosity, of the command-line tools
12173 @cindex build logs, verbosity
12174 @item -v @var{level}
12175 @itemx --verbosity=@var{level}
12176 Use the given verbosity @var{level}, an integer. Choosing 0 means that
12177 no output is produced, 1 is for quiet output; 2 is similar to 1 but it
12178 additionally displays download URLs; 3 shows all the build log output on
12181 @item --cores=@var{n}
12183 Allow the use of up to @var{n} CPU cores for the build. The special
12184 value @code{0} means to use as many CPU cores as available.
12186 @item --max-jobs=@var{n}
12188 Allow at most @var{n} build jobs in parallel. @xref{Invoking
12189 guix-daemon, @option{--max-jobs}}, for details about this option and the
12190 equivalent @command{guix-daemon} option.
12192 @item --debug=@var{level}
12193 Produce debugging output coming from the build daemon. @var{level} must be an
12194 integer between 0 and 5; higher means more verbose output. Setting a level of
12195 4 or more may be helpful when debugging setup issues with the build daemon.
12199 Behind the scenes, @command{guix build} is essentially an interface to
12200 the @code{package-derivation} procedure of the @code{(guix packages)}
12201 module, and to the @code{build-derivations} procedure of the @code{(guix
12202 derivations)} module.
12204 In addition to options explicitly passed on the command line,
12205 @command{guix build} and other @command{guix} commands that support
12206 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
12208 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
12209 Users can define this variable to a list of command line options that
12210 will automatically be used by @command{guix build} and other
12211 @command{guix} commands that can perform builds, as in the example
12215 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
12218 These options are parsed independently, and the result is appended to
12219 the parsed command-line options.
12223 @node Package Transformation Options
12224 @subsection Package Transformation Options
12226 @cindex package variants
12227 Another set of command-line options supported by @command{guix build}
12228 and also @command{guix package} are @dfn{package transformation
12229 options}. These are options that make it possible to define @dfn{package
12230 variants}---for instance, packages built from different source code.
12231 This is a convenient way to create customized packages on the fly
12232 without having to type in the definitions of package variants
12233 (@pxref{Defining Packages}).
12235 Package transformation options are preserved across upgrades:
12236 @command{guix upgrade} attempts to apply transformation options
12237 initially used when creating the profile to the upgraded packages.
12239 The available options are listed below. Most commands support them and
12240 also support a @option{--help-transform} option that lists all the
12241 available options and a synopsis (these options are not shown in the
12242 @option{--help} output for brevity).
12246 @cindex performance, tuning code
12247 @cindex optimization, of package code
12248 @cindex tuning, of package code
12249 @cindex SIMD support
12250 @cindex tunable packages
12251 @cindex package multi-versioning
12252 @item --tune[=@var{cpu}]
12253 Use versions of the packages marked as ``tunable'' optimized for
12254 @var{cpu}. When @var{cpu} is @code{native}, or when it is omitted, tune
12255 for the CPU on which the @command{guix} command is running.
12257 Valid @var{cpu} names are those recognized by the underlying compiler,
12258 by default the GNU Compiler Collection. On x86_64 processors, this
12259 includes CPU names such as @code{nehalem}, @code{haswell}, and
12260 @code{skylake} (@pxref{x86 Options, @code{-march},, gcc, Using the GNU
12261 Compiler Collection (GCC)}).
12263 As new generations of CPUs come out, they augment the standard
12264 instruction set architecture (ISA) with additional instructions, in
12265 particular instructions for single-instruction/multiple-data (SIMD)
12266 parallel processing. For example, while Core2 and Skylake CPUs both
12267 implement the x86_64 ISA, only the latter supports AVX2 SIMD
12270 The primary gain one can expect from @option{--tune} is for programs
12271 that can make use of those SIMD capabilities @emph{and} that do not
12272 already have a mechanism to select the right optimized code at run time.
12273 Packages that have the @code{tunable?} property set are considered
12274 @dfn{tunable packages} by the @option{--tune} option; a package
12275 definition with the property set looks like this:
12279 (name "hello-simd")
12282 ;; This package may benefit from SIMD extensions so
12283 ;; mark it as "tunable".
12284 (properties '((tunable? . #t))))
12287 Other packages are not considered tunable. This allows Guix to use
12288 generic binaries in the cases where tuning for a specific CPU is
12289 unlikely to provide any gain.
12291 Tuned packages are built with @code{-march=@var{CPU}}; under the hood,
12292 the @option{-march} option is passed to the actual wrapper by a compiler
12293 wrapper. Since the build machine may not be able to run code for the
12294 target CPU micro-architecture, the test suite is not run when building a
12297 To reduce rebuilds to the minimum, tuned packages are @emph{grafted}
12298 onto packages that depend on them (@pxref{Security Updates, grafts}).
12299 Thus, using @option{--no-grafts} cancels the effect of @option{--tune}.
12301 We call this technique @dfn{package multi-versioning}: several variants
12302 of tunable packages may be built, one for each CPU variant. It is the
12303 coarse-grain counterpart of @dfn{function multi-versioning} as
12304 implemented by the GNU tool chain (@pxref{Function Multiversioning,,,
12305 gcc, Using the GNU Compiler Collection (GCC)}).
12307 @item --with-source=@var{source}
12308 @itemx --with-source=@var{package}=@var{source}
12309 @itemx --with-source=@var{package}@@@var{version}=@var{source}
12310 Use @var{source} as the source of @var{package}, and @var{version} as
12311 its version number.
12312 @var{source} must be a file name or a URL, as for @command{guix
12313 download} (@pxref{Invoking guix download}).
12315 When @var{package} is omitted,
12316 it is taken to be the package name specified on the
12317 command line that matches the base of @var{source}---e.g.,
12318 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
12319 package is @code{guile}.
12321 Likewise, when @var{version} is omitted, the version string is inferred from
12322 @var{source}; in the previous example, it is @code{2.0.10}.
12324 This option allows users to try out versions of packages other than the
12325 one provided by the distribution. The example below downloads
12326 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
12327 the @code{ed} package:
12330 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
12333 As a developer, @option{--with-source} makes it easy to test release
12337 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
12340 @dots{} or to build from a checkout in a pristine environment:
12343 $ git clone git://git.sv.gnu.org/guix.git
12344 $ guix build guix --with-source=guix@@1.0=./guix
12347 @item --with-input=@var{package}=@var{replacement}
12348 Replace dependency on @var{package} by a dependency on
12349 @var{replacement}. @var{package} must be a package name, and
12350 @var{replacement} must be a package specification such as @code{guile}
12351 or @code{guile@@1.8}.
12353 For instance, the following command builds Guix, but replaces its
12354 dependency on the current stable version of Guile with a dependency on
12355 the legacy version of Guile, @code{guile@@2.0}:
12358 guix build --with-input=guile=guile@@2.0 guix
12361 This is a recursive, deep replacement. So in this example, both
12362 @code{guix} and its dependency @code{guile-json} (which also depends on
12363 @code{guile}) get rebuilt against @code{guile@@2.0}.
12365 This is implemented using the @code{package-input-rewriting} Scheme
12366 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
12368 @item --with-graft=@var{package}=@var{replacement}
12369 This is similar to @option{--with-input} but with an important difference:
12370 instead of rebuilding the whole dependency chain, @var{replacement} is
12371 built and then @dfn{grafted} onto the binaries that were initially
12372 referring to @var{package}. @xref{Security Updates}, for more
12373 information on grafts.
12375 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
12376 and all its dependencies, replacing references to the version of GnuTLS
12377 they currently refer to:
12380 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
12383 This has the advantage of being much faster than rebuilding everything.
12384 But there is a caveat: it works if and only if @var{package} and
12385 @var{replacement} are strictly compatible---for example, if they provide
12386 a library, the application binary interface (ABI) of those libraries
12387 must be compatible. If @var{replacement} is somehow incompatible with
12388 @var{package}, then the resulting package may be unusable. Use with
12391 @cindex debugging info, rebuilding
12392 @item --with-debug-info=@var{package}
12393 Build @var{package} in a way that preserves its debugging info and graft
12394 it onto packages that depend on it. This is useful if @var{package}
12395 does not already provide debugging info as a @code{debug} output
12396 (@pxref{Installing Debugging Files}).
12398 For example, suppose you're experiencing a crash in Inkscape and would
12399 like to see what's up in GLib, a library deep down in Inkscape's
12400 dependency graph. GLib lacks a @code{debug} output, so debugging is
12401 tough. Fortunately, you rebuild GLib with debugging info and tack it on
12405 guix install inkscape --with-debug-info=glib
12408 Only GLib needs to be recompiled so this takes a reasonable amount of
12409 time. @xref{Installing Debugging Files}, for more info.
12412 Under the hood, this option works by passing the @samp{#:strip-binaries?
12413 #f} to the build system of the package of interest (@pxref{Build
12414 Systems}). Most build systems support that option but some do not. In
12415 that case, an error is raised.
12417 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
12418 the case), debugging info will remain unavailable even when
12419 @code{#:strip-binaries?} is false.
12422 @cindex tool chain, changing the build tool chain of a package
12423 @item --with-c-toolchain=@var{package}=@var{toolchain}
12424 This option changes the compilation of @var{package} and everything that
12425 depends on it so that they get built with @var{toolchain} instead of the
12426 default GNU tool chain for C/C++.
12428 Consider this example:
12431 guix build octave-cli \
12432 --with-c-toolchain=fftw=gcc-toolchain@@10 \
12433 --with-c-toolchain=fftwf=gcc-toolchain@@10
12436 The command above builds a variant of the @code{fftw} and @code{fftwf}
12437 packages using version 10 of @code{gcc-toolchain} instead of the default
12438 tool chain, and then builds a variant of the GNU@tie{}Octave
12439 command-line interface using them. GNU@tie{}Octave itself is also built
12440 with @code{gcc-toolchain@@10}.
12442 This other example builds the Hardware Locality (@code{hwloc}) library
12443 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
12447 guix build --with-c-toolchain=hwloc=clang-toolchain \
12448 intel-mpi-benchmarks
12452 There can be application binary interface (ABI) incompatibilities among
12453 tool chains. This is particularly true of the C++ standard library and
12454 run-time support libraries such as that of OpenMP@. By rebuilding all
12455 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
12456 the risks of incompatibility but cannot entirely eliminate them. Choose
12457 @var{package} wisely.
12460 @item --with-git-url=@var{package}=@var{url}
12461 @cindex Git, using the latest commit
12462 @cindex latest commit, building
12463 Build @var{package} from the latest commit of the @code{master} branch of the
12464 Git repository at @var{url}. Git sub-modules of the repository are fetched,
12467 For example, the following command builds the NumPy Python library against the
12468 latest commit of the master branch of Python itself:
12471 guix build python-numpy \
12472 --with-git-url=python=https://github.com/python/cpython
12475 This option can also be combined with @option{--with-branch} or
12476 @option{--with-commit} (see below).
12478 @cindex continuous integration
12479 Obviously, since it uses the latest commit of the given branch, the result of
12480 such a command varies over time. Nevertheless it is a convenient way to
12481 rebuild entire software stacks against the latest commit of one or more
12482 packages. This is particularly useful in the context of continuous
12485 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
12486 consecutive accesses to the same repository. You may want to clean it up once
12487 in a while to save disk space.
12489 @item --with-branch=@var{package}=@var{branch}
12490 Build @var{package} from the latest commit of @var{branch}. If the
12491 @code{source} field of @var{package} is an origin with the @code{git-fetch}
12492 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
12493 repository URL is taken from that @code{source}. Otherwise you have to use
12494 @option{--with-git-url} to specify the URL of the Git repository.
12496 For instance, the following command builds @code{guile-sqlite3} from the
12497 latest commit of its @code{master} branch, and then builds @code{guix} (which
12498 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
12499 specific @code{guile-sqlite3} build:
12502 guix build --with-branch=guile-sqlite3=master cuirass
12505 @item --with-commit=@var{package}=@var{commit}
12506 This is similar to @option{--with-branch}, except that it builds from
12507 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
12508 Git commit SHA1 identifier, a tag, or a @command{git describe} style
12509 identifier such as @code{1.0-3-gabc123}.
12511 @item --with-patch=@var{package}=@var{file}
12512 Add @var{file} to the list of patches applied to @var{package}, where
12513 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
12514 @var{file} must contain a patch; it is applied with the flags specified
12515 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
12516 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
12517 Comparing and Merging Files}).
12519 As an example, the command below rebuilds Coreutils with the GNU C
12520 Library (glibc) patched with the given patch:
12523 guix build coreutils --with-patch=glibc=./glibc-frob.patch
12526 In this example, glibc itself as well as everything that leads to
12527 Coreutils in the dependency graph is rebuilt.
12529 @cindex upstream, latest version
12530 @item --with-latest=@var{package}
12531 So you like living on the bleeding edge? This option is for you! It
12532 replaces occurrences of @var{package} in the dependency graph with its
12533 latest upstream version, as reported by @command{guix refresh}
12534 (@pxref{Invoking guix refresh}).
12536 It does so by determining the latest upstream release of @var{package}
12537 (if possible), downloading it, and authenticating it @emph{if} it comes
12538 with an OpenPGP signature.
12540 As an example, the command below builds Guix against the latest version
12544 guix build guix --with-latest=guile-json
12547 There are limitations. First, in cases where the tool cannot or does
12548 not know how to authenticate source code, you are at risk of running
12549 malicious code; a warning is emitted in this case. Second, this option
12550 simply changes the source used in the existing package definitions,
12551 which is not always sufficient: there might be additional dependencies
12552 that need to be added, patches to apply, and more generally the quality
12553 assurance work that Guix developers normally do will be missing.
12555 You've been warned! In all the other cases, it's a snappy way to stay
12556 on top. We encourage you to submit patches updating the actual package
12557 definitions once you have successfully tested an upgrade
12558 (@pxref{Contributing}).
12560 @cindex test suite, skipping
12561 @item --without-tests=@var{package}
12562 Build @var{package} without running its tests. This can be useful in
12563 situations where you want to skip the lengthy test suite of a
12564 intermediate package, or if a package's test suite fails in a
12565 non-deterministic fashion. It should be used with care because running
12566 the test suite is a good way to ensure a package is working as intended.
12568 Turning off tests leads to a different store item. Consequently, when
12569 using this option, anything that depends on @var{package} must be
12570 rebuilt, as in this example:
12573 guix install --without-tests=python python-notebook
12576 The command above installs @code{python-notebook} on top of
12577 @code{python} built without running its test suite. To do so, it also
12578 rebuilds everything that depends on @code{python}, including
12579 @code{python-notebook} itself.
12581 Internally, @option{--without-tests} relies on changing the
12582 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
12583 Systems}). Note that some packages use a customized @code{check} phase
12584 that does not respect a @code{#:tests? #f} setting. Therefore,
12585 @option{--without-tests} has no effect on these packages.
12589 Wondering how to achieve the same effect using Scheme code, for example
12590 in your manifest, or how to write your own package transformation?
12591 @xref{Defining Package Variants}, for an overview of the programming
12592 interfaces available.
12594 @node Additional Build Options
12595 @subsection Additional Build Options
12597 The command-line options presented below are specific to @command{guix
12604 Build quietly, without displaying the build log; this is equivalent to
12605 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
12606 (or similar) and can always be retrieved using the @option{--log-file} option.
12608 @item --file=@var{file}
12609 @itemx -f @var{file}
12610 Build the package, derivation, or other file-like object that the code within
12611 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
12613 As an example, @var{file} might contain a package definition like this
12614 (@pxref{Defining Packages}):
12617 @include package-hello.scm
12620 The @var{file} may also contain a JSON representation of one or more
12621 package definitions. Running @code{guix build -f} on @file{hello.json}
12622 with the following contents would result in building the packages
12623 @code{myhello} and @code{greeter}:
12626 @verbatiminclude package-hello.json
12629 @item --manifest=@var{manifest}
12630 @itemx -m @var{manifest}
12631 Build all packages listed in the given @var{manifest}
12632 (@pxref{profile-manifest, @option{--manifest}}).
12634 @item --expression=@var{expr}
12635 @itemx -e @var{expr}
12636 Build the package or derivation @var{expr} evaluates to.
12638 For example, @var{expr} may be @code{(@@ (gnu packages guile)
12639 guile-1.8)}, which unambiguously designates this specific variant of
12640 version 1.8 of Guile.
12642 Alternatively, @var{expr} may be a G-expression, in which case it is used
12643 as a build program passed to @code{gexp->derivation}
12644 (@pxref{G-Expressions}).
12646 Lastly, @var{expr} may refer to a zero-argument monadic procedure
12647 (@pxref{The Store Monad}). The procedure must return a derivation as a
12648 monadic value, which is then passed through @code{run-with-store}.
12652 Build the source derivations of the packages, rather than the packages
12655 For instance, @code{guix build -S gcc} returns something like
12656 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
12659 The returned source tarball is the result of applying any patches and
12660 code snippets specified in the package @code{origin} (@pxref{Defining
12663 @cindex source, verification
12664 As with other derivations, the result of building a source derivation
12665 can be verified using the @option{--check} option (@pxref{build-check}).
12666 This is useful to validate that a (potentially already built or
12667 substituted, thus cached) package source matches against its declared
12670 Note that @command{guix build -S} compiles the sources only of the
12671 specified packages. They do not include the sources of statically
12672 linked dependencies and by themselves are insufficient for reproducing
12676 Fetch and return the source of @var{package-or-derivation} and all their
12677 dependencies, recursively. This is a handy way to obtain a local copy
12678 of all the source code needed to build @var{packages}, allowing you to
12679 eventually build them even without network access. It is an extension
12680 of the @option{--source} option and can accept one of the following
12681 optional argument values:
12685 This value causes the @option{--sources} option to behave in the same way
12686 as the @option{--source} option.
12689 Build the source derivations of all packages, including any source that
12690 might be listed as @code{inputs}. This is the default value.
12693 $ guix build --sources tzdata
12694 The following derivations will be built:
12695 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
12696 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12700 Build the source derivations of all packages, as well of all transitive
12701 inputs to the packages. This can be used e.g.@: to
12702 prefetch package source for later offline building.
12705 $ guix build --sources=transitive tzdata
12706 The following derivations will be built:
12707 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12708 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
12709 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
12710 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
12711 /gnu/store/@dots{}-make-4.1.tar.xz.drv
12712 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
12718 @item --system=@var{system}
12719 @itemx -s @var{system}
12720 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
12721 the system type of the build host. The @command{guix build} command allows
12722 you to repeat this option several times, in which case it builds for all the
12723 specified systems; other commands ignore extraneous @option{-s} options.
12726 The @option{--system} flag is for @emph{native} compilation and must not
12727 be confused with cross-compilation. See @option{--target} below for
12728 information on cross-compilation.
12731 An example use of this is on Linux-based systems, which can emulate
12732 different personalities. For instance, passing
12733 @option{--system=i686-linux} on an @code{x86_64-linux} system or
12734 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
12735 you to build packages in a complete 32-bit environment.
12738 Building for an @code{armhf-linux} system is unconditionally enabled on
12739 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
12740 allow for this functionality, notably the ThunderX.
12743 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
12744 is enabled (@pxref{Virtualization Services,
12745 @code{qemu-binfmt-service-type}}), you can build for any system for
12746 which a QEMU @code{binfmt_misc} handler is installed.
12748 Builds for a system other than that of the machine you are using can
12749 also be offloaded to a remote machine of the right architecture.
12750 @xref{Daemon Offload Setup}, for more information on offloading.
12752 @item --target=@var{triplet}
12753 @cindex cross-compilation
12754 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
12755 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
12756 configuration triplets,, autoconf, Autoconf}).
12758 @item --list-systems
12759 List all the supported systems, that can be passed as an argument to
12762 @item --list-targets
12763 List all the supported targets, that can be passed as an argument to
12766 @anchor{build-check}
12768 @cindex determinism, checking
12769 @cindex reproducibility, checking
12770 Rebuild @var{package-or-derivation}, which are already available in the
12771 store, and raise an error if the build results are not bit-for-bit
12774 This mechanism allows you to check whether previously installed
12775 substitutes are genuine (@pxref{Substitutes}), or whether the build result
12776 of a package is deterministic. @xref{Invoking guix challenge}, for more
12777 background information and tools.
12779 When used in conjunction with @option{--keep-failed}, the differing
12780 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12781 This makes it easy to look for differences between the two results.
12784 @cindex repairing store items
12785 @cindex corruption, recovering from
12786 Attempt to repair the specified store items, if they are corrupt, by
12787 re-downloading or rebuilding them.
12789 This operation is not atomic and thus restricted to @code{root}.
12791 @item --derivations
12793 Return the derivation paths, not the output paths, of the given
12796 @item --root=@var{file}
12797 @itemx -r @var{file}
12798 @cindex GC roots, adding
12799 @cindex garbage collector roots, adding
12800 Make @var{file} a symlink to the result, and register it as a garbage
12803 Consequently, the results of this @command{guix build} invocation are
12804 protected from garbage collection until @var{file} is removed. When
12805 that option is omitted, build results are eligible for garbage
12806 collection as soon as the build completes. @xref{Invoking guix gc}, for
12810 @cindex build logs, access
12811 Return the build log file names or URLs for the given
12812 @var{package-or-derivation}, or raise an error if build logs are
12815 This works regardless of how packages or derivations are specified. For
12816 instance, the following invocations are equivalent:
12819 guix build --log-file $(guix build -d guile)
12820 guix build --log-file $(guix build guile)
12821 guix build --log-file guile
12822 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
12825 If a log is unavailable locally, and unless @option{--no-substitutes} is
12826 passed, the command looks for a corresponding log on one of the
12827 substitute servers (as specified with @option{--substitute-urls}).
12829 So for instance, imagine you want to see the build log of GDB on
12830 @code{aarch64}, but you are actually on an @code{x86_64} machine:
12833 $ guix build --log-file gdb -s aarch64-linux
12834 https://@value{SUBSTITUTE-SERVER-1}/log/@dots{}-gdb-7.10
12837 You can freely access a huge library of build logs!
12840 @node Debugging Build Failures
12841 @subsection Debugging Build Failures
12843 @cindex build failures, debugging
12844 When defining a new package (@pxref{Defining Packages}), you will
12845 probably find yourself spending some time debugging and tweaking the
12846 build until it succeeds. To do that, you need to operate the build
12847 commands yourself in an environment as close as possible to the one the
12850 To that end, the first thing to do is to use the @option{--keep-failed}
12851 or @option{-K} option of @command{guix build}, which will keep the
12852 failed build tree in @file{/tmp} or whatever directory you specified as
12853 @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
12855 From there on, you can @command{cd} to the failed build tree and source
12856 the @file{environment-variables} file, which contains all the
12857 environment variable definitions that were in place when the build
12858 failed. So let's say you're debugging a build failure in package
12859 @code{foo}; a typical session would look like this:
12862 $ guix build foo -K
12863 @dots{} @i{build fails}
12864 $ cd /tmp/guix-build-foo.drv-0
12865 $ source ./environment-variables
12869 Now, you can invoke commands as if you were the daemon (almost) and
12870 troubleshoot your build process.
12872 Sometimes it happens that, for example, a package's tests pass when you
12873 run them manually but they fail when the daemon runs them. This can
12874 happen because the daemon runs builds in containers where, unlike in our
12875 environment above, network access is missing, @file{/bin/sh} does not
12876 exist, etc. (@pxref{Build Environment Setup}).
12878 In such cases, you may need to run inspect the build process from within
12879 a container similar to the one the build daemon creates:
12882 $ guix build -K foo
12884 $ cd /tmp/guix-build-foo.drv-0
12885 $ guix shell --no-grafts -C -D foo strace gdb
12886 [env]# source ./environment-variables
12890 Here, @command{guix shell -C} creates a container and spawns a new
12891 shell in it (@pxref{Invoking guix shell}). The @command{strace gdb}
12892 part adds the @command{strace} and @command{gdb} commands to
12893 the container, which you may find handy while debugging. The
12894 @option{--no-grafts} option makes sure we get the exact same
12895 environment, with ungrafted packages (@pxref{Security Updates}, for more
12898 To get closer to a container like that used by the build daemon, we can
12899 remove @file{/bin/sh}:
12905 (Don't worry, this is harmless: this is all happening in the throw-away
12906 container created by @command{guix shell}.)
12908 The @command{strace} command is probably not in the search path, but we
12912 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
12915 In this way, not only you will have reproduced the environment variables
12916 the daemon uses, you will also be running the build process in a container
12917 similar to the one the daemon uses.
12920 @node Invoking guix edit
12921 @section Invoking @command{guix edit}
12923 @cindex @command{guix edit}
12924 @cindex package definition, editing
12925 So many packages, so many source files! The @command{guix edit} command
12926 facilitates the life of users and packagers by pointing their editor at
12927 the source file containing the definition of the specified packages.
12931 guix edit gcc@@4.9 vim
12935 launches the program specified in the @env{VISUAL} or in the
12936 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
12939 If you are using a Guix Git checkout (@pxref{Building from Git}), or
12940 have created your own packages on @env{GUIX_PACKAGE_PATH}
12941 (@pxref{Package Modules}), you will be able to edit the package
12942 recipes. In other cases, you will be able to examine the read-only recipes
12943 for packages currently in the store.
12945 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
12946 @option{--load-path=@var{directory}} (or in short @option{-L
12947 @var{directory}}) allows you to add @var{directory} to the front of the
12948 package module search path and so make your own packages visible.
12950 @node Invoking guix download
12951 @section Invoking @command{guix download}
12953 @cindex @command{guix download}
12954 @cindex downloading package sources
12955 When writing a package definition, developers typically need to download
12956 a source tarball, compute its SHA256 hash, and write that
12957 hash in the package definition (@pxref{Defining Packages}). The
12958 @command{guix download} tool helps with this task: it downloads a file
12959 from the given URI, adds it to the store, and prints both its file name
12960 in the store and its SHA256 hash.
12962 The fact that the downloaded file is added to the store saves bandwidth:
12963 when the developer eventually tries to build the newly defined package
12964 with @command{guix build}, the source tarball will not have to be
12965 downloaded again because it is already in the store. It is also a
12966 convenient way to temporarily stash files, which may be deleted
12967 eventually (@pxref{Invoking guix gc}).
12969 The @command{guix download} command supports the same URIs as used in
12970 package definitions. In particular, it supports @code{mirror://} URIs.
12971 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
12972 Guile bindings for GnuTLS are available in the user's environment; when
12973 they are not available, an error is raised. @xref{Guile Preparations,
12974 how to install the GnuTLS bindings for Guile,, gnutls-guile,
12975 GnuTLS-Guile}, for more information.
12977 @command{guix download} verifies HTTPS server certificates by loading
12978 the certificates of X.509 authorities from the directory pointed to by
12979 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
12980 Certificates}), unless @option{--no-check-certificate} is used.
12982 The following options are available:
12985 @item --hash=@var{algorithm}
12986 @itemx -H @var{algorithm}
12987 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
12988 hash}, for more information.
12990 @item --format=@var{fmt}
12991 @itemx -f @var{fmt}
12992 Write the hash in the format specified by @var{fmt}. For more
12993 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
12995 @item --no-check-certificate
12996 Do not validate the X.509 certificates of HTTPS servers.
12998 When using this option, you have @emph{absolutely no guarantee} that you
12999 are communicating with the authentic server responsible for the given
13000 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
13002 @item --output=@var{file}
13003 @itemx -o @var{file}
13004 Save the downloaded file to @var{file} instead of adding it to the
13008 @node Invoking guix hash
13009 @section Invoking @command{guix hash}
13011 @cindex @command{guix hash}
13012 The @command{guix hash} command computes the hash of a file.
13013 It is primarily a convenience tool for anyone contributing to the
13014 distribution: it computes the cryptographic hash of one or more files, which can be
13015 used in the definition of a package (@pxref{Defining Packages}).
13017 The general syntax is:
13020 guix hash @var{option} @var{file} ...
13023 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
13024 hash of data read from standard input. @command{guix hash} has the
13029 @item --hash=@var{algorithm}
13030 @itemx -H @var{algorithm}
13031 Compute a hash using the specified @var{algorithm}, @code{sha256} by
13034 @var{algorithm} must be the name of a cryptographic hash algorithm
13035 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
13036 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
13037 Reference Manual}).
13039 @item --format=@var{fmt}
13040 @itemx -f @var{fmt}
13041 Write the hash in the format specified by @var{fmt}.
13043 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
13044 (@code{hex} and @code{hexadecimal} can be used as well).
13046 If the @option{--format} option is not specified, @command{guix hash}
13047 will output the hash in @code{nix-base32}. This representation is used
13048 in the definitions of packages.
13052 The @option{--recursive} option is deprecated in favor of
13053 @option{--serializer=nar} (see below); @option{-r} remains accepted as a
13054 convenient shorthand.
13056 @item --serializer=@var{type}
13057 @itemx -S @var{type}
13058 Compute the hash on @var{file} using @var{type} serialization.
13060 @var{type} may be one of the following:
13064 This is the default: it computes the hash of a file's contents.
13067 Compute the hash of a ``normalized archive'' (or ``nar'') containing
13068 @var{file}, including its children if it is a directory. Some of the
13069 metadata of @var{file} is part of the archive; for instance, when
13070 @var{file} is a regular file, the hash is different depending on whether
13071 @var{file} is executable or not. Metadata such as time stamps have no
13072 impact on the hash (@pxref{Invoking guix archive}, for more info on the
13074 @c FIXME: Replace xref above with xref to an ``Archive'' section when
13078 Compute the hash of the file or directory as a Git ``tree'', following
13079 the same method as the Git version control system.
13082 @item --exclude-vcs
13084 When combined with @option{--recursive}, exclude version control system
13085 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
13088 As an example, here is how you would compute the hash of a Git checkout,
13089 which is useful when using the @code{git-fetch} method (@pxref{origin
13093 $ git clone http://example.org/foo.git
13095 $ guix hash -x --serializer=nar .
13099 @node Invoking guix import
13100 @section Invoking @command{guix import}
13102 @cindex importing packages
13103 @cindex package import
13104 @cindex package conversion
13105 @cindex Invoking @command{guix import}
13106 The @command{guix import} command is useful for people who would like to
13107 add a package to the distribution with as little work as
13108 possible---a legitimate demand. The command knows of a few
13109 repositories from which it can ``import'' package metadata. The result
13110 is a package definition, or a template thereof, in the format we know
13111 (@pxref{Defining Packages}).
13113 The general syntax is:
13116 guix import @var{importer} @var{options}@dots{}
13119 @var{importer} specifies the source from which to import package
13120 metadata, and @var{options} specifies a package identifier and other
13121 options specific to @var{importer}.
13123 Some of the importers rely on the ability to run the @command{gpgv} command.
13124 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
13127 Currently, the available ``importers'' are:
13131 Import metadata for the given GNU package. This provides a template
13132 for the latest version of that GNU package, including the hash of its
13133 source tarball, and its canonical synopsis and description.
13135 Additional information such as the package dependencies and its
13136 license needs to be figured out manually.
13138 For example, the following command returns a package definition for
13142 guix import gnu hello
13145 Specific command-line options are:
13148 @item --key-download=@var{policy}
13149 As for @command{guix refresh}, specify the policy to handle missing
13150 OpenPGP keys when verifying the package signature. @xref{Invoking guix
13151 refresh, @option{--key-download}}.
13156 Import metadata from the @uref{https://pypi.python.org/, Python Package
13157 Index}. Information is taken from the JSON-formatted description
13158 available at @code{pypi.python.org} and usually includes all the relevant
13159 information, including package dependencies. For maximum efficiency, it
13160 is recommended to install the @command{unzip} utility, so that the
13161 importer can unzip Python wheels and gather data from them.
13163 The command below imports metadata for the latest version of the
13164 @code{itsdangerous} Python package:
13167 guix import pypi itsdangerous
13170 You can also ask for a specific version:
13173 guix import pypi itsdangerous@@1.1.0
13179 Traverse the dependency graph of the given upstream package recursively
13180 and generate package expressions for all those packages that are not yet
13186 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
13187 is taken from the JSON-formatted description available at
13188 @code{rubygems.org} and includes most relevant information, including
13189 runtime dependencies. There are some caveats, however. The metadata
13190 doesn't distinguish between synopses and descriptions, so the same string
13191 is used for both fields. Additionally, the details of non-Ruby
13192 dependencies required to build native extensions is unavailable and left
13193 as an exercise to the packager.
13195 The command below imports metadata for the @code{rails} Ruby package:
13198 guix import gem rails
13204 Traverse the dependency graph of the given upstream package recursively
13205 and generate package expressions for all those packages that are not yet
13212 Import metadata from @uref{https://content.minetest.net, ContentDB}.
13213 Information is taken from the JSON-formatted metadata provided through
13214 @uref{https://content.minetest.net/help/api/, ContentDB's API} and
13215 includes most relevant information, including dependencies. There are
13216 some caveats, however. The license information is often incomplete.
13217 The commit hash is sometimes missing. The descriptions are in the
13218 Markdown format, but Guix uses Texinfo instead. Texture packs and
13219 subgames are unsupported.
13221 The command below imports metadata for the Mesecons mod by Jeija:
13224 guix import minetest Jeija/mesecons
13227 The author name can also be left out:
13230 guix import minetest mesecons
13236 Traverse the dependency graph of the given upstream package recursively
13237 and generate package expressions for all those packages that are not yet
13243 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
13244 Information is taken from the JSON-formatted metadata provided through
13245 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
13246 relevant information, such as module dependencies. License information
13247 should be checked closely. If Perl is available in the store, then the
13248 @code{corelist} utility will be used to filter core modules out of the
13249 list of dependencies.
13251 The command command below imports metadata for the Acme::Boolean Perl
13255 guix import cpan Acme::Boolean
13260 @cindex Bioconductor
13261 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
13262 central repository for the @uref{https://r-project.org, GNU@tie{}R
13263 statistical and graphical environment}.
13265 Information is extracted from the @file{DESCRIPTION} file of the package.
13267 The command command below imports metadata for the Cairo R package:
13270 guix import cran Cairo
13273 You can also ask for a specific version:
13276 guix import cran rasterVis@@0.50.3
13279 When @option{--recursive} is added, the importer will traverse the
13280 dependency graph of the given upstream package recursively and generate
13281 package expressions for all those packages that are not yet in Guix.
13283 When @option{--style=specification} is added, the importer will generate
13284 package definitions whose inputs are package specifications instead of
13285 references to package variables. This is useful when generated package
13286 definitions are to be appended to existing user modules, as the list of
13287 used package modules need not be changed. The default is
13288 @option{--style=variable}.
13290 When @option{--archive=bioconductor} is added, metadata is imported from
13291 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
13292 packages for the analysis and comprehension of high-throughput
13293 genomic data in bioinformatics.
13295 Information is extracted from the @file{DESCRIPTION} file contained in the
13298 The command below imports metadata for the GenomicRanges R package:
13301 guix import cran --archive=bioconductor GenomicRanges
13304 Finally, you can also import R packages that have not yet been published on
13305 CRAN or Bioconductor as long as they are in a git repository. Use
13306 @option{--archive=git} followed by the URL of the git repository:
13309 guix import cran --archive=git https://github.com/immunogenomics/harmony
13315 Import TeX package information from the TeX Live package database for
13316 TeX packages that are part of the @uref{https://www.tug.org/texlive/,
13317 TeX Live distribution}.
13319 Information about the package is obtained from the TeX Live package
13320 database, a plain text file that is included in the @code{texlive-bin}
13321 package. The source code is downloaded from possibly multiple locations
13322 in the SVN repository of the Tex Live project.
13324 The command command below imports metadata for the @code{fontspec}
13328 guix import texlive fontspec
13332 @cindex JSON, import
13333 Import package metadata from a local JSON file. Consider the following
13334 example package definition in JSON format:
13340 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
13341 "build-system": "gnu",
13342 "home-page": "https://www.gnu.org/software/hello/",
13343 "synopsis": "Hello, GNU world: An example GNU package",
13344 "description": "GNU Hello prints a greeting.",
13345 "license": "GPL-3.0+",
13346 "native-inputs": ["gettext"]
13350 The field names are the same as for the @code{<package>} record
13351 (@xref{Defining Packages}). References to other packages are provided
13352 as JSON lists of quoted package specification strings such as
13353 @code{guile} or @code{guile@@2.0}.
13355 The importer also supports a more explicit source definition using the
13356 common fields for @code{<origin>} records:
13362 "method": "url-fetch",
13363 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
13365 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
13372 The command below reads metadata from the JSON file @code{hello.json}
13373 and outputs a package expression:
13376 guix import json hello.json
13381 Import metadata from the Haskell community's central package archive
13382 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
13383 Cabal files and includes all the relevant information, including package
13386 Specific command-line options are:
13391 Read a Cabal file from standard input.
13392 @item --no-test-dependencies
13394 Do not include dependencies required only by the test suites.
13395 @item --cabal-environment=@var{alist}
13396 @itemx -e @var{alist}
13397 @var{alist} is a Scheme alist defining the environment in which the
13398 Cabal conditionals are evaluated. The accepted keys are: @code{os},
13399 @code{arch}, @code{impl} and a string representing the name of a flag.
13400 The value associated with a flag has to be either the symbol
13401 @code{true} or @code{false}. The value associated with other keys
13402 has to conform to the Cabal file format definition. The default value
13403 associated with the keys @code{os}, @code{arch} and @code{impl} is
13404 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
13407 Traverse the dependency graph of the given upstream package recursively
13408 and generate package expressions for all those packages that are not yet
13412 The command below imports metadata for the latest version of the
13413 HTTP Haskell package without including test dependencies and
13414 specifying the value of the flag @samp{network-uri} as @code{false}:
13417 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
13420 A specific package version may optionally be specified by following the
13421 package name by an at-sign and a version number as in the following example:
13424 guix import hackage mtl@@2.1.3.1
13429 The @code{stackage} importer is a wrapper around the @code{hackage} one.
13430 It takes a package name, looks up the package version included in a
13431 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
13432 release and uses the @code{hackage} importer to retrieve its metadata.
13433 Note that it is up to you to select an LTS release compatible with the
13434 GHC compiler used by Guix.
13436 Specific command-line options are:
13439 @item --no-test-dependencies
13441 Do not include dependencies required only by the test suites.
13442 @item --lts-version=@var{version}
13443 @itemx -l @var{version}
13444 @var{version} is the desired LTS release version. If omitted the latest
13448 Traverse the dependency graph of the given upstream package recursively
13449 and generate package expressions for all those packages that are not yet
13453 The command below imports metadata for the HTTP Haskell package
13454 included in the LTS Stackage release version 7.18:
13457 guix import stackage --lts-version=7.18 HTTP
13462 Import metadata from an Emacs Lisp Package Archive (ELPA) package
13463 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
13465 Specific command-line options are:
13468 @item --archive=@var{repo}
13469 @itemx -a @var{repo}
13470 @var{repo} identifies the archive repository from which to retrieve the
13471 information. Currently the supported repositories and their identifiers
13475 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
13476 identifier. This is the default.
13478 Packages from @code{elpa.gnu.org} are signed with one of the keys
13479 contained in the GnuPG keyring at
13480 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
13481 @code{emacs} package (@pxref{Package Installation, ELPA package
13482 signatures,, emacs, The GNU Emacs Manual}).
13485 @uref{https://elpa.nongnu.org/nongnu/, NonGNU}, selected by the
13486 @code{nongnu} identifier.
13489 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
13490 @code{melpa-stable} identifier.
13493 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
13499 Traverse the dependency graph of the given upstream package recursively
13500 and generate package expressions for all those packages that are not yet
13506 Import metadata from the crates.io Rust package repository
13507 @uref{https://crates.io, crates.io}, as in this example:
13510 guix import crate blake2-rfc
13513 The crate importer also allows you to specify a version string:
13516 guix import crate constant-time-eq@@0.1.0
13519 Additional options include:
13524 Traverse the dependency graph of the given upstream package recursively
13525 and generate package expressions for all those packages that are not yet
13531 Import metadata from the Elm package repository
13532 @uref{https://package.elm-lang.org, package.elm-lang.org}, as in this example:
13535 guix import elm elm-explorations/webgl
13538 The Elm importer also allows you to specify a version string:
13541 guix import elm elm-explorations/webgl@@1.1.3
13544 Additional options include:
13549 Traverse the dependency graph of the given upstream package recursively
13550 and generate package expressions for all those packages that are not yet
13557 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
13558 repository used by the OCaml community.
13560 Additional options include:
13565 Traverse the dependency graph of the given upstream package recursively
13566 and generate package expressions for all those packages that are not yet
13569 By default, packages are searched in the official OPAM repository. This
13570 option, which can be used more than once, lets you add other repositories
13571 which will be searched for packages. It accepts as valid arguments:
13574 @item the name of a known repository - can be one of @code{opam},
13575 @code{coq} (equivalent to @code{coq-released}),
13576 @code{coq-core-dev}, @code{coq-extra-dev} or @code{grew}.
13577 @item the URL of a repository as expected by the
13578 @code{opam repository add} command (for instance, the URL equivalent
13579 of the above @code{opam} name would be
13580 @uref{https://opam.ocaml.org}).
13581 @item the path to a local copy of a repository (a directory containing a
13582 @file{packages/} sub-directory).
13585 Repositories are assumed to be passed to this option by order of
13586 preference. The additional repositories will not replace the default
13587 @code{opam} repository, which is always kept as a fallback.
13589 Also, please note that versions are not compared across repositories.
13590 The first repository (from left to right) that has at least one version
13591 of a given package will prevail over any others, and the version
13592 imported will be the latest one found @emph{in this repository only}.
13598 Import metadata for a Go module using
13599 @uref{https://proxy.golang.org, proxy.golang.org}.
13602 guix import go gopkg.in/yaml.v2
13605 It is possible to use a package specification with a @code{@@VERSION}
13606 suffix to import a specific version.
13608 Additional options include:
13613 Traverse the dependency graph of the given upstream package recursively
13614 and generate package expressions for all those packages that are not yet
13616 @item --pin-versions
13617 When using this option, the importer preserves the exact versions of the
13618 Go modules dependencies instead of using their latest available
13619 versions. This can be useful when attempting to import packages that
13620 recursively depend on former versions of themselves to build. When
13621 using this mode, the symbol of the package is made by appending the
13622 version to its name, so that multiple versions of the same package can
13628 Import metadata for @uref{https://wiki.call-cc.org/eggs, CHICKEN eggs}.
13629 The information is taken from @file{PACKAGE.egg} files found in the
13630 @uref{git://code.call-cc.org/eggs-5-all, eggs-5-all} Git
13631 repository. However, it does not provide all the information that we
13632 need, there is no ``description'' field, and the licenses used are not
13633 always precise (BSD is often used instead of BSD-N).
13636 guix import egg sourcehut
13639 You can also ask for a specific version:
13642 guix import egg arrays@@1.0
13645 Additional options include:
13649 Traverse the dependency graph of the given upstream package recursively
13650 and generate package expressions for all those packages that are not yet
13656 Import metadata from the hex.pm Erlang and Elixir package repository
13657 @uref{https://hex.pm, hex.pm}, as in this example:
13660 guix import hexpm stun
13663 The importer tries to determine the build system used by the package.
13665 The hexpm importer also allows you to specify a version string:
13668 guix import hexpm cf@@0.3.0
13671 Additional options include:
13676 Traverse the dependency graph of the given upstream package recursively
13677 and generate package expressions for all those packages that are not yet
13682 The structure of the @command{guix import} code is modular. It would be
13683 useful to have more importers for other package formats, and your help
13684 is welcome here (@pxref{Contributing}).
13686 @node Invoking guix refresh
13687 @section Invoking @command{guix refresh}
13689 @cindex @command {guix refresh}
13690 The primary audience of the @command{guix refresh} command is packagers.
13691 As a user, you may be interested in the @option{--with-latest} option,
13692 which can bring you package update superpowers built upon @command{guix
13693 refresh} (@pxref{Package Transformation Options,
13694 @option{--with-latest}}). By default, @command{guix refresh} reports
13695 any packages provided by the distribution that are outdated compared to
13696 the latest upstream version, like this:
13700 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
13701 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
13704 Alternatively, one can specify packages to consider, in which case a
13705 warning is emitted for packages that lack an updater:
13708 $ guix refresh coreutils guile guile-ssh
13709 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
13710 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
13713 @command{guix refresh} browses the upstream repository of each package and determines
13714 the highest version number of the releases therein. The command
13715 knows how to update specific types of packages: GNU packages, ELPA
13716 packages, etc.---see the documentation for @option{--type} below. There
13717 are many packages, though, for which it lacks a method to determine
13718 whether a new upstream release is available. However, the mechanism is
13719 extensible, so feel free to get in touch with us to add a new method!
13724 Consider the packages specified, and all the packages upon which they depend.
13727 $ guix refresh --recursive coreutils
13728 gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
13729 gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
13730 gnu/packages/xml.scm:68:2: warning: no updater for expat
13731 gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
13737 Sometimes the upstream name differs from the package name used in Guix,
13738 and @command{guix refresh} needs a little help. Most updaters honor the
13739 @code{upstream-name} property in package definitions, which can be used
13743 (define-public network-manager
13745 (name "network-manager")
13747 (properties '((upstream-name . "NetworkManager")))))
13750 When passed @option{--update}, it modifies distribution source files to
13751 update the version numbers and source tarball hashes of those package
13752 recipes (@pxref{Defining Packages}). This is achieved by downloading
13753 each package's latest source tarball and its associated OpenPGP
13754 signature, authenticating the downloaded tarball against its signature
13755 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
13756 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
13759 key used to sign the tarball is missing from the user's keyring, an
13760 attempt is made to automatically retrieve it from a public key server;
13761 when this is successful, the key is added to the user's keyring; otherwise,
13762 @command{guix refresh} reports an error.
13764 The following options are supported:
13768 @item --expression=@var{expr}
13769 @itemx -e @var{expr}
13770 Consider the package @var{expr} evaluates to.
13772 This is useful to precisely refer to a package, as in this example:
13775 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
13778 This command lists the dependents of the ``final'' libc (essentially all
13783 Update distribution source files (package recipes) in place. This is
13784 usually run from a checkout of the Guix source tree (@pxref{Running
13785 Guix Before It Is Installed}):
13788 $ ./pre-inst-env guix refresh -s non-core -u
13791 @xref{Defining Packages}, for more information on package definitions.
13793 @item --select=[@var{subset}]
13794 @itemx -s @var{subset}
13795 Select all the packages in @var{subset}, one of @code{core} or
13798 The @code{core} subset refers to all the packages at the core of the
13799 distribution---i.e., packages that are used to build ``everything
13800 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
13801 changing one of these packages in the distribution entails a rebuild of
13802 all the others. Thus, such updates are an inconvenience to users in
13803 terms of build time or bandwidth used to achieve the upgrade.
13805 The @code{non-core} subset refers to the remaining packages. It is
13806 typically useful in cases where an update of the core packages would be
13809 @item --manifest=@var{file}
13810 @itemx -m @var{file}
13811 Select all the packages from the manifest in @var{file}. This is useful to
13812 check if any packages of the user manifest can be updated.
13814 @item --type=@var{updater}
13815 @itemx -t @var{updater}
13816 Select only packages handled by @var{updater} (may be a comma-separated
13817 list of updaters). Currently, @var{updater} may be one of:
13821 the updater for GNU packages;
13823 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
13825 the updater for packages hosted at @uref{https://sourceforge.net, SourceForge};
13827 the updater for GNOME packages;
13829 the updater for KDE packages;
13831 the updater for X.org packages;
13833 the updater for packages hosted on kernel.org;
13835 the updater for @uref{https://wiki.call-cc.org/eggs/, Egg} packages;
13837 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
13839 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
13841 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
13843 the updater for @uref{https://www.cpan.org/, CPAN} packages;
13845 the updater for @uref{https://pypi.python.org, PyPI} packages.
13847 the updater for @uref{https://rubygems.org, RubyGems} packages.
13849 the updater for @uref{https://github.com, GitHub} packages.
13851 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
13853 the updater for @uref{https://www.stackage.org, Stackage} packages.
13855 the updater for @uref{https://crates.io, Crates} packages.
13857 the updater for @uref{https://launchpad.net, Launchpad} packages.
13859 a generic updater that crawls the HTML page where the source tarball of
13860 the package is hosted, when applicable.
13863 a generic updater for packages hosted on Git repositories. It tries to
13864 be smart about parsing Git tag names, but if it is not able to parse the
13865 tag name and compare tags correctly, users can define the following
13866 properties for a package.
13869 @item @code{release-tag-prefix}: a regular expression for matching a prefix of
13872 @item @code{release-tag-suffix}: a regular expression for matching a suffix of
13875 @item @code{release-tag-version-delimiter}: a string used as the delimiter in
13876 the tag name for separating the numbers of the version.
13878 @item @code{accept-pre-releases}: by default, the updater will ignore
13879 pre-releases; to make it also look for pre-releases, set the this
13880 property to @code{#t}.
13889 '((release-tag-prefix . "^release0-")
13890 (release-tag-suffix . "[a-z]?$")
13891 (release-tag-version-delimiter . ":"))))
13897 For instance, the following command only checks for updates of Emacs
13898 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
13901 $ guix refresh --type=elpa,cran
13902 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
13903 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
13906 @item --list-updaters
13907 List available updaters and exit (see @option{--type} above).
13909 For each updater, display the fraction of packages it covers; at the
13910 end, display the fraction of packages covered by all these updaters.
13913 In addition, @command{guix refresh} can be passed one or more package
13914 names, as in this example:
13917 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
13921 The command above specifically updates the @code{emacs} and
13922 @code{idutils} packages. The @option{--select} option would have no
13923 effect in this case. You might also want to update definitions that
13924 correspond to the packages installed in your profile:
13927 $ ./pre-inst-env guix refresh -u \
13928 $(guix package --list-installed | cut -f1)
13931 When considering whether to upgrade a package, it is sometimes
13932 convenient to know which packages would be affected by the upgrade and
13933 should be checked for compatibility. For this the following option may
13934 be used when passing @command{guix refresh} one or more package names:
13938 @item --list-dependent
13940 List top-level dependent packages that would need to be rebuilt as a
13941 result of upgrading one or more packages.
13943 @xref{Invoking guix graph, the @code{reverse-package} type of
13944 @command{guix graph}}, for information on how to visualize the list of
13945 dependents of a package.
13949 Be aware that the @option{--list-dependent} option only
13950 @emph{approximates} the rebuilds that would be required as a result of
13951 an upgrade. More rebuilds might be required under some circumstances.
13954 $ guix refresh --list-dependent flex
13955 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
13956 hop@@2.4.0 emacs-geiser@@0.13 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
13959 The command above lists a set of packages that could be built to check
13960 for compatibility with an upgraded @code{flex} package.
13964 @item --list-transitive
13965 List all the packages which one or more packages depend upon.
13968 $ guix refresh --list-transitive flex
13969 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
13970 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{}
13975 The command above lists a set of packages which, when changed, would cause
13976 @code{flex} to be rebuilt.
13978 The following options can be used to customize GnuPG operation:
13982 @item --gpg=@var{command}
13983 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
13984 for in @code{$PATH}.
13986 @item --keyring=@var{file}
13987 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
13988 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
13989 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
13990 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
13991 information on a tool to manipulate keybox files).
13993 When this option is omitted, @command{guix refresh} uses
13994 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
13995 signing keys. OpenPGP signatures are checked against keys from this keyring;
13996 missing keys are downloaded to this keyring as well (see
13997 @option{--key-download} below).
13999 You can export keys from your default GPG keyring into a keybox file using
14000 commands like this one:
14003 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
14006 Likewise, you can fetch keys to a specific keybox file like this:
14009 gpg --no-default-keyring --keyring mykeyring.kbx \
14010 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
14013 @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
14014 Privacy Guard}, for more information on GPG's @option{--keyring} option.
14016 @item --key-download=@var{policy}
14017 Handle missing OpenPGP keys according to @var{policy}, which may be one
14022 Always download missing OpenPGP keys from the key server, and add them
14023 to the user's GnuPG keyring.
14026 Never try to download missing OpenPGP keys. Instead just bail out.
14029 When a package signed with an unknown OpenPGP key is encountered, ask
14030 the user whether to download it or not. This is the default behavior.
14033 @item --key-server=@var{host}
14034 Use @var{host} as the OpenPGP key server when importing a public key.
14036 @item --load-path=@var{directory}
14037 @itemx -L @var{directory}
14038 Add @var{directory} to the front of the package module search path
14039 (@pxref{Package Modules}).
14041 This allows users to define their own packages and make them visible to
14042 the command-line tools.
14046 The @code{github} updater uses the
14047 @uref{https://developer.github.com/v3/, GitHub API} to query for new
14048 releases. When used repeatedly e.g.@: when refreshing all packages,
14049 GitHub will eventually refuse to answer any further API requests. By
14050 default 60 API requests per hour are allowed, and a full refresh on all
14051 GitHub packages in Guix requires more than this. Authentication with
14052 GitHub through the use of an API token alleviates these limits. To use
14053 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
14054 token procured from @uref{https://github.com/settings/tokens} or
14058 @node Invoking guix style
14059 @section Invoking @command{guix style}
14061 The @command{guix style} command helps packagers style their package
14062 definitions according to the latest fashionable trends. The command
14063 currently provides the following styling rules:
14067 formatting package definitions according to the project's conventions
14068 (@pxref{Formatting Code});
14071 rewriting package inputs to the ``new style'', as explained below.
14074 The way package inputs are written is going through a transition
14075 (@pxref{package Reference}, for more on package inputs). Until version
14076 1.3.0, package inputs were written using the ``old style'', where each
14077 input was given an explicit label, most of the time the package name:
14082 ;; The "old style" (deprecated).
14083 (inputs `(("libunistring" ,libunistring)
14084 ("libffi" ,libffi))))
14087 Today, the old style is deprecated and the preferred style looks like
14093 ;; The "new style".
14094 (inputs (list libunistring libffi)))
14097 Likewise, uses of @code{alist-delete} and friends to manipulate inputs
14098 is now deprecated in favor of @code{modify-inputs} (@pxref{Defining
14099 Package Variants}, for more info on @code{modify-inputs}).
14101 In the vast majority of cases, this is a purely mechanical change on the
14102 surface syntax that does not even incur a package rebuild. Running
14103 @command{guix style -S inputs} can do that for you, whether you're working on
14104 packages in Guix proper or in an external channel.
14106 The general syntax is:
14109 guix style [@var{options}] @var{package}@dots{}
14112 This causes @command{guix style} to analyze and rewrite the definition
14113 of @var{package}@dots{} or, when @var{package} is omitted, of @emph{all}
14114 the packages. The @option{--styling} or @option{-S} option allows you
14115 to select the style rule, the default rule being @code{format}---see
14118 The available options are listed below.
14123 Show source file locations that would be edited but do not modify them.
14125 @item --styling=@var{rule}
14126 @itemx -S @var{rule}
14127 Apply @var{rule}, one of the following styling rules:
14131 Format the given package definition(s)---this is the default styling
14132 rule. For example, a packager running Guix on a checkout
14133 (@pxref{Running Guix Before It Is Installed}) might want to reformat the
14134 definition of the Coreutils package like so:
14137 ./pre-inst-env guix style coreutils
14141 Rewrite package inputs to the ``new style'', as described above. This
14142 is how you would rewrite inputs of package @code{whatnot} in your own
14146 guix style -L ~/my/channel -S inputs whatnot
14149 Rewriting is done in a conservative way: preserving comments and bailing
14150 out if it cannot make sense of the code that appears in an inputs field.
14151 The @option{--input-simplification} option described below provides
14152 fine-grain control over when inputs should be simplified.
14155 @item --list-stylings
14157 List and describe the available styling rules and exit.
14159 @item --load-path=@var{directory}
14160 @itemx -L @var{directory}
14161 Add @var{directory} to the front of the package module search path
14162 (@pxref{Package Modules}).
14164 @item --expression=@var{expr}
14165 @itemx -e @var{expr}
14166 Style the package @var{expr} evaluates to.
14168 For example, running:
14171 guix style -e '(@@ (gnu packages gcc) gcc-5)'
14174 styles the @code{gcc-5} package definition.
14176 @item --input-simplification=@var{policy}
14177 When using the @code{inputs} styling rule, with @samp{-S inputs}, this
14178 option specifies the package input simplification policy for cases where
14179 an input label does not match the corresponding package name.
14180 @var{policy} may be one of the following:
14184 Simplify inputs only when the change is ``silent'', meaning that the
14185 package does not need to be rebuilt (its derivation is unchanged).
14188 Simplify inputs only when that is ``safe'' to do: the package might need
14189 to be rebuilt, but the change is known to have no observable effect.
14192 Simplify inputs even when input labels do not match package names, and
14193 even if that might have an observable effect.
14196 The default is @code{silent}, meaning that input simplifications do not
14197 trigger any package rebuild.
14200 @node Invoking guix lint
14201 @section Invoking @command{guix lint}
14203 @cindex @command{guix lint}
14204 @cindex package, checking for errors
14205 The @command{guix lint} command is meant to help package developers avoid
14206 common errors and use a consistent style. It runs a number of checks on
14207 a given set of packages in order to find common mistakes in their
14208 definitions. Available @dfn{checkers} include (see
14209 @option{--list-checkers} for a complete list):
14214 Validate certain typographical and stylistic rules about package
14215 descriptions and synopses.
14217 @item inputs-should-be-native
14218 Identify inputs that should most likely be native inputs.
14224 @itemx source-file-name
14225 Probe @code{home-page} and @code{source} URLs and report those that are
14226 invalid. Suggest a @code{mirror://} URL when applicable. If the
14227 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
14228 URL@. Check that the source file name is meaningful, e.g.@: is not just a
14229 version number or ``git-checkout'', without a declared @code{file-name}
14230 (@pxref{origin Reference}).
14232 @item source-unstable-tarball
14233 Parse the @code{source} URL to determine if a tarball from GitHub is
14234 autogenerated or if it is a release tarball. Unfortunately GitHub's
14235 autogenerated tarballs are sometimes regenerated.
14238 Check that the derivation of the given packages can be successfully
14239 computed for all the supported systems (@pxref{Derivations}).
14241 @item profile-collisions
14242 Check whether installing the given packages in a profile would lead to
14243 collisions. Collisions occur when several packages with the same name
14244 but a different version or a different store file name are propagated.
14245 @xref{package Reference, @code{propagated-inputs}}, for more information
14246 on propagated inputs.
14249 @cindex Software Heritage, source code archive
14250 @cindex archival of source code, Software Heritage
14251 Checks whether the package's source code is archived at
14252 @uref{https://www.softwareheritage.org, Software Heritage}.
14254 When the source code that is not archived comes from a version-control system
14255 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
14256 ``save'' request so that it eventually archives it. This ensures that the
14257 source will remain available in the long term, and that Guix can fall back to
14258 Software Heritage should the source code disappear from its original host.
14259 The status of recent ``save'' requests can be
14260 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
14262 When source code is a tarball obtained with @code{url-fetch}, simply print a
14263 message when it is not archived. As of this writing, Software Heritage does
14264 not allow requests to save arbitrary tarballs; we are working on ways to
14265 ensure that non-VCS source code is also archived.
14268 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
14269 request rate per IP address}. When the limit is reached, @command{guix lint}
14270 prints a message and the @code{archival} checker stops doing anything until
14271 that limit has been reset.
14274 @cindex security vulnerabilities
14275 @cindex CVE, Common Vulnerabilities and Exposures
14276 Report known vulnerabilities found in the Common Vulnerabilities and
14277 Exposures (CVE) databases of the current and past year
14278 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
14281 To view information about a particular vulnerability, visit pages such as:
14285 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
14287 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
14291 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
14292 @code{CVE-2015-7554}.
14294 Package developers can specify in package recipes the
14295 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
14296 name and version of the package when they differ from the name or version
14297 that Guix uses, as in this example:
14303 ;; CPE calls this package "grub2".
14304 (properties '((cpe-name . "grub2")
14305 (cpe-version . "2.3"))))
14308 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
14309 Some entries in the CVE database do not specify which version of a
14310 package they apply to, and would thus ``stick around'' forever. Package
14311 developers who found CVE alerts and verified they can be ignored can
14312 declare them as in this example:
14318 ;; These CVEs no longer apply and can be safely ignored.
14319 (properties `((lint-hidden-cve . ("CVE-2011-0433"
14322 "CVE-2011-5244")))))
14326 Warn about obvious source code formatting issues: trailing white space,
14327 use of tabulations, etc.
14330 Report old-style input labels that do not match the name of the
14331 corresponding package. This aims to help migrate from the ``old input
14332 style''. @xref{package Reference}, for more information on package
14333 inputs and input styles. @xref{Invoking guix style}, on how to migrate
14337 The general syntax is:
14340 guix lint @var{options} @var{package}@dots{}
14343 If no package is given on the command line, then all packages are checked.
14344 The @var{options} may be zero or more of the following:
14347 @item --list-checkers
14349 List and describe all the available checkers that will be run on packages
14354 Only enable the checkers specified in a comma-separated list using the
14355 names returned by @option{--list-checkers}.
14359 Only disable the checkers specified in a comma-separated list using the
14360 names returned by @option{--list-checkers}.
14364 Only enable the checkers that do not depend on Internet access.
14366 @item --load-path=@var{directory}
14367 @itemx -L @var{directory}
14368 Add @var{directory} to the front of the package module search path
14369 (@pxref{Package Modules}).
14371 This allows users to define their own packages and make them visible to
14372 the command-line tools.
14376 @node Invoking guix size
14377 @section Invoking @command{guix size}
14380 @cindex package size
14382 @cindex @command{guix size}
14383 The @command{guix size} command helps package developers profile the
14384 disk usage of packages. It is easy to overlook the impact of an
14385 additional dependency added to a package, or the impact of using a
14386 single output for a package that could easily be split (@pxref{Packages
14387 with Multiple Outputs}). Such are the typical issues that
14388 @command{guix size} can highlight.
14390 The command can be passed one or more package specifications
14391 such as @code{gcc@@4.8}
14392 or @code{guile:debug}, or a file name in the store. Consider this
14396 $ guix size coreutils
14397 store item total self
14398 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
14399 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
14400 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
14401 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
14402 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
14403 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
14404 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
14405 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
14410 The store items listed here constitute the @dfn{transitive closure} of
14411 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
14412 would be returned by:
14415 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
14418 Here the output shows three columns next to store items. The first column,
14419 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
14420 the store item---that is, its own size plus the size of all its
14421 dependencies. The next column, labeled ``self'', shows the size of the
14422 item itself. The last column shows the ratio of the size of the item
14423 itself to the space occupied by all the items listed here.
14425 In this example, we see that the closure of Coreutils weighs in at
14426 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
14427 libraries. (That libc and GCC's libraries represent a large fraction of
14428 the closure is not a problem @i{per se} because they are always available
14429 on the system anyway.)
14431 Since the command also accepts store file names, assessing the size of
14432 a build result is straightforward:
14435 guix size $(guix system build config.scm)
14438 When the package(s) passed to @command{guix size} are available in the
14439 store@footnote{More precisely, @command{guix size} looks for the
14440 @emph{ungrafted} variant of the given package(s), as returned by
14441 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
14442 for information on grafts.}, @command{guix size} queries the daemon to determine its
14443 dependencies, and measures its size in the store, similar to @command{du
14444 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
14447 When the given packages are @emph{not} in the store, @command{guix size}
14448 reports information based on the available substitutes
14449 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
14450 store items that are not even on disk, only available remotely.
14452 You can also specify several package names:
14455 $ guix size coreutils grep sed bash
14456 store item total self
14457 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
14458 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
14459 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
14460 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
14466 In this example we see that the combination of the four packages takes
14467 102.3@tie{}MiB in total, which is much less than the sum of each closure
14468 since they have a lot of dependencies in common.
14470 When looking at the profile returned by @command{guix size}, you may
14471 find yourself wondering why a given package shows up in the profile at
14472 all. To understand it, you can use @command{guix graph --path -t
14473 references} to display the shortest path between the two packages
14474 (@pxref{Invoking guix graph}).
14476 The available options are:
14480 @item --substitute-urls=@var{urls}
14481 Use substitute information from @var{urls}.
14482 @xref{client-substitute-urls, the same option for @code{guix build}}.
14484 @item --sort=@var{key}
14485 Sort lines according to @var{key}, one of the following options:
14489 the size of each item (the default);
14491 the total size of the item's closure.
14494 @item --map-file=@var{file}
14495 Write a graphical map of disk usage in PNG format to @var{file}.
14497 For the example above, the map looks like this:
14499 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
14500 produced by @command{guix size}}
14502 This option requires that
14503 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
14504 installed and visible in Guile's module search path. When that is not
14505 the case, @command{guix size} fails as it tries to load it.
14507 @item --system=@var{system}
14508 @itemx -s @var{system}
14509 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
14511 @item --load-path=@var{directory}
14512 @itemx -L @var{directory}
14513 Add @var{directory} to the front of the package module search path
14514 (@pxref{Package Modules}).
14516 This allows users to define their own packages and make them visible to
14517 the command-line tools.
14520 @node Invoking guix graph
14521 @section Invoking @command{guix graph}
14524 @cindex @command{guix graph}
14525 @cindex package dependencies
14526 Packages and their dependencies form a @dfn{graph}, specifically a
14527 directed acyclic graph (DAG). It can quickly become difficult to have a
14528 mental model of the package DAG, so the @command{guix graph} command
14529 provides a visual representation of the DAG@. By default,
14530 @command{guix graph} emits a DAG representation in the input format of
14531 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
14532 directly to the @command{dot} command of Graphviz. It can also emit an
14533 HTML page with embedded JavaScript code to display a ``chord diagram''
14534 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
14535 emit Cypher queries to construct a graph in a graph database supporting
14536 the @uref{https://www.opencypher.org/, openCypher} query language. With
14537 @option{--path}, it simply displays the shortest path between two
14538 packages. The general syntax is:
14541 guix graph @var{options} @var{package}@dots{}
14544 For example, the following command generates a PDF file representing the
14545 package DAG for the GNU@tie{}Core Utilities, showing its build-time
14549 guix graph coreutils | dot -Tpdf > dag.pdf
14552 The output looks like this:
14554 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
14556 Nice little graph, no?
14558 You may find it more pleasant to navigate the graph interactively with
14559 @command{xdot} (from the @code{xdot} package):
14562 guix graph coreutils | xdot -
14565 But there is more than one graph! The one above is concise: it is the
14566 graph of package objects, omitting implicit inputs such as GCC, libc,
14567 grep, etc. It is often useful to have such a concise graph, but
14568 sometimes one may want to see more details. @command{guix graph} supports
14569 several types of graphs, allowing you to choose the level of detail:
14573 This is the default type used in the example above. It shows the DAG of
14574 package objects, excluding implicit dependencies. It is concise, but
14575 filters out many details.
14577 @item reverse-package
14578 This shows the @emph{reverse} DAG of packages. For example:
14581 guix graph --type=reverse-package ocaml
14584 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
14585 you are also interested in cases where OCaml is an implicit dependency, see
14586 @code{reverse-bag} below).
14588 Note that for core packages this can yield huge graphs. If all you want
14589 is to know the number of packages that depend on a given package, use
14590 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
14591 @option{--list-dependent}}).
14594 This is the package DAG, @emph{including} implicit inputs.
14596 For instance, the following command:
14599 guix graph --type=bag-emerged coreutils
14602 ...@: yields this bigger graph:
14604 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
14606 At the bottom of the graph, we see all the implicit inputs of
14607 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
14609 Now, note that the dependencies of these implicit inputs---that is, the
14610 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
14611 here, for conciseness.
14614 Similar to @code{bag-emerged}, but this time including all the bootstrap
14617 @item bag-with-origins
14618 Similar to @code{bag}, but also showing origins and their dependencies.
14621 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
14622 it also takes implicit dependencies into account. For example:
14625 guix graph -t reverse-bag dune
14629 ...@: yields the graph of all packages that depend on Dune, directly or
14630 indirectly. Since Dune is an @emph{implicit} dependency of many packages
14631 @i{via} @code{dune-build-system}, this shows a large number of packages,
14632 whereas @code{reverse-package} would show very few if any.
14635 This is the most detailed representation: It shows the DAG of
14636 derivations (@pxref{Derivations}) and plain store items. Compared to
14637 the above representation, many additional nodes are visible, including
14638 build scripts, patches, Guile modules, etc.
14640 For this type of graph, it is also possible to pass a @file{.drv} file
14641 name instead of a package name, as in:
14644 guix graph -t derivation $(guix system build -d my-config.scm)
14648 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
14649 For example, the following command shows the graph for the package
14650 module that defines the @code{guile} package:
14653 guix graph -t module guile | xdot -
14657 All the types above correspond to @emph{build-time dependencies}. The
14658 following graph type represents the @emph{run-time dependencies}:
14662 This is the graph of @dfn{references} of a package output, as returned
14663 by @command{guix gc --references} (@pxref{Invoking guix gc}).
14665 If the given package output is not available in the store, @command{guix
14666 graph} attempts to obtain dependency information from substitutes.
14668 Here you can also pass a store file name instead of a package name. For
14669 example, the command below produces the reference graph of your profile
14670 (which can be big!):
14673 guix graph -t references $(readlink -f ~/.guix-profile)
14677 This is the graph of the @dfn{referrers} of a store item, as returned by
14678 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
14680 This relies exclusively on local information from your store. For
14681 instance, let us suppose that the current Inkscape is available in 10
14682 profiles on your machine; @command{guix graph -t referrers inkscape}
14683 will show a graph rooted at Inkscape and with those 10 profiles linked
14686 It can help determine what is preventing a store item from being garbage
14691 @cindex shortest path, between packages
14692 Often, the graph of the package you are interested in does not fit on
14693 your screen, and anyway all you want to know is @emph{why} that package
14694 actually depends on some seemingly unrelated package. The
14695 @option{--path} option instructs @command{guix graph} to display the
14696 shortest path between two packages (or derivations, or store items,
14700 $ guix graph --path emacs libunistring
14703 libunistring@@0.9.10
14704 $ guix graph --path -t derivation emacs libunistring
14705 /gnu/store/@dots{}-emacs-26.3.drv
14706 /gnu/store/@dots{}-mailutils-3.9.drv
14707 /gnu/store/@dots{}-libunistring-0.9.10.drv
14708 $ guix graph --path -t references emacs libunistring
14709 /gnu/store/@dots{}-emacs-26.3
14710 /gnu/store/@dots{}-libidn2-2.2.0
14711 /gnu/store/@dots{}-libunistring-0.9.10
14714 Sometimes you still want to visualize the graph but would like to trim
14715 it so it can actually be displayed. One way to do it is via the
14716 @option{--max-depth} (or @option{-M}) option, which lets you specify the
14717 maximum depth of the graph. In the example below, we visualize only
14718 @code{libreoffice} and the nodes whose distance to @code{libreoffice} is
14722 guix graph -M 2 libreoffice | xdot -f fdp -
14725 Mind you, that's still a big ball of spaghetti, but at least
14726 @command{dot} can render it quickly and it can be browsed somewhat.
14728 The available options are the following:
14731 @item --type=@var{type}
14732 @itemx -t @var{type}
14733 Produce a graph output of @var{type}, where @var{type} must be one of
14734 the values listed above.
14737 List the supported graph types.
14739 @item --backend=@var{backend}
14740 @itemx -b @var{backend}
14741 Produce a graph using the selected @var{backend}.
14743 @item --list-backends
14744 List the supported graph backends.
14746 Currently, the available backends are Graphviz and d3.js.
14749 Display the shortest path between two nodes of the type specified by
14750 @option{--type}. The example below shows the shortest path between
14751 @code{libreoffice} and @code{llvm} according to the references of
14752 @code{libreoffice}:
14755 $ guix graph --path -t references libreoffice llvm
14756 /gnu/store/@dots{}-libreoffice-6.4.2.2
14757 /gnu/store/@dots{}-libepoxy-1.5.4
14758 /gnu/store/@dots{}-mesa-19.3.4
14759 /gnu/store/@dots{}-llvm-9.0.1
14762 @item --expression=@var{expr}
14763 @itemx -e @var{expr}
14764 Consider the package @var{expr} evaluates to.
14766 This is useful to precisely refer to a package, as in this example:
14769 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
14772 @item --system=@var{system}
14773 @itemx -s @var{system}
14774 Display the graph for @var{system}---e.g., @code{i686-linux}.
14776 The package dependency graph is largely architecture-independent, but there
14777 are some architecture-dependent bits that this option allows you to visualize.
14779 @item --load-path=@var{directory}
14780 @itemx -L @var{directory}
14781 Add @var{directory} to the front of the package module search path
14782 (@pxref{Package Modules}).
14784 This allows users to define their own packages and make them visible to
14785 the command-line tools.
14788 On top of that, @command{guix graph} supports all the usual package
14789 transformation options (@pxref{Package Transformation Options}). This
14790 makes it easy to view the effect of a graph-rewriting transformation
14791 such as @option{--with-input}. For example, the command below outputs
14792 the graph of @code{git} once @code{openssl} has been replaced by
14793 @code{libressl} everywhere in the graph:
14796 guix graph git --with-input=openssl=libressl
14799 So many possibilities, so much fun!
14801 @node Invoking guix publish
14802 @section Invoking @command{guix publish}
14804 @cindex @command{guix publish}
14805 The purpose of @command{guix publish} is to enable users to easily share
14806 their store with others, who can then use it as a substitute server
14807 (@pxref{Substitutes}).
14809 When @command{guix publish} runs, it spawns an HTTP server which allows
14810 anyone with network access to obtain substitutes from it. This means
14811 that any machine running Guix can also act as if it were a build farm,
14812 since the HTTP interface is compatible with Cuirass, the software behind
14813 the @code{@value{SUBSTITUTE-SERVER-1}} build farm.
14815 For security, each substitute is signed, allowing recipients to check
14816 their authenticity and integrity (@pxref{Substitutes}). Because
14817 @command{guix publish} uses the signing key of the system, which is only
14818 readable by the system administrator, it must be started as root; the
14819 @option{--user} option makes it drop root privileges early on.
14821 The signing key pair must be generated before @command{guix publish} is
14822 launched, using @command{guix archive --generate-key} (@pxref{Invoking
14825 When the @option{--advertise} option is passed, the server advertises
14826 its availability on the local network using multicast DNS (mDNS) and DNS
14827 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
14828 guile-avahi, Using Avahi in Guile Scheme Programs}).
14830 The general syntax is:
14833 guix publish @var{options}@dots{}
14836 Running @command{guix publish} without any additional arguments will
14837 spawn an HTTP server on port 8080:
14843 @cindex socket activation, for @command{guix publish}
14844 @command{guix publish} can also be started following the systemd
14845 ``socket activation'' protocol (@pxref{Service De- and Constructors,
14846 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
14848 Once a publishing server has been authorized, the daemon may download
14849 substitutes from it. @xref{Getting Substitutes from Other Servers}.
14851 By default, @command{guix publish} compresses archives on the fly as it
14852 serves them. This ``on-the-fly'' mode is convenient in that it requires
14853 no setup and is immediately available. However, when serving lots of
14854 clients, we recommend using the @option{--cache} option, which enables
14855 caching of the archives before they are sent to clients---see below for
14856 details. The @command{guix weather} command provides a handy way to
14857 check what a server provides (@pxref{Invoking guix weather}).
14859 As a bonus, @command{guix publish} also serves as a content-addressed
14860 mirror for source files referenced in @code{origin} records
14861 (@pxref{origin Reference}). For instance, assuming @command{guix
14862 publish} is running on @code{example.org}, the following URL returns the
14863 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
14864 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
14867 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
14870 Obviously, these URLs only work for files that are in the store; in
14871 other cases, they return 404 (``Not Found'').
14873 @cindex build logs, publication
14874 Build logs are available from @code{/log} URLs like:
14877 http://example.org/log/gwspk@dots{}-guile-2.2.3
14881 When @command{guix-daemon} is configured to save compressed build logs,
14882 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
14883 URLs return the compressed log as-is, with an appropriate
14884 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
14885 running @command{guix-daemon} with @option{--log-compression=gzip} since
14886 Web browsers can automatically decompress it, which is not the case with
14889 The following options are available:
14892 @item --port=@var{port}
14893 @itemx -p @var{port}
14894 Listen for HTTP requests on @var{port}.
14896 @item --listen=@var{host}
14897 Listen on the network interface for @var{host}. The default is to
14898 accept connections from any interface.
14900 @item --user=@var{user}
14901 @itemx -u @var{user}
14902 Change privileges to @var{user} as soon as possible---i.e., once the
14903 server socket is open and the signing key has been read.
14905 @item --compression[=@var{method}[:@var{level}]]
14906 @itemx -C [@var{method}[:@var{level}]]
14907 Compress data using the given @var{method} and @var{level}. @var{method} is
14908 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
14909 omitted, @code{gzip} is used.
14911 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
14912 to different compression levels: 1 is the fastest, and 9 is the best
14913 (CPU-intensive). The default is 3.
14915 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
14916 small increase in CPU usage; see
14917 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
14918 Web page}. However, @code{lzip} achieves low decompression throughput
14919 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
14920 bottleneck for someone who downloads over a fast network connection.
14922 The compression ratio of @code{zstd} is between that of @code{lzip} and
14923 that of @code{gzip}; its main advantage is a
14924 @uref{https://facebook.github.io/zstd/,high decompression speed}.
14926 Unless @option{--cache} is used, compression occurs on the fly and
14927 the compressed streams are not
14928 cached. Thus, to reduce load on the machine that runs @command{guix
14929 publish}, it may be a good idea to choose a low compression level, to
14930 run @command{guix publish} behind a caching proxy, or to use
14931 @option{--cache}. Using @option{--cache} has the advantage that it
14932 allows @command{guix publish} to add @code{Content-Length} HTTP header
14935 This option can be repeated, in which case every substitute gets compressed
14936 using all the selected methods, and all of them are advertised. This is
14937 useful when users may not support all the compression methods: they can select
14938 the one they support.
14940 @item --cache=@var{directory}
14941 @itemx -c @var{directory}
14942 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
14943 and only serve archives that are in cache.
14945 When this option is omitted, archives and meta-data are created
14946 on-the-fly. This can reduce the available bandwidth, especially when
14947 compression is enabled, since this may become CPU-bound. Another
14948 drawback of the default mode is that the length of archives is not known
14949 in advance, so @command{guix publish} does not add a
14950 @code{Content-Length} HTTP header to its responses, which in turn
14951 prevents clients from knowing the amount of data being downloaded.
14953 Conversely, when @option{--cache} is used, the first request for a store
14954 item (@i{via} a @code{.narinfo} URL) triggers a
14955 background process to @dfn{bake} the archive---computing its
14956 @code{.narinfo} and compressing the archive, if needed. Once the
14957 archive is cached in @var{directory}, subsequent requests succeed and
14958 are served directly from the cache, which guarantees that clients get
14959 the best possible bandwidth.
14961 That first @code{.narinfo} request nonetheless returns 200, provided the
14962 requested store item is ``small enough'', below the cache bypass
14963 threshold---see @option{--cache-bypass-threshold} below. That way,
14964 clients do not have to wait until the archive is baked. For larger
14965 store items, the first @code{.narinfo} request returns 404, meaning that
14966 clients have to wait until the archive is baked.
14968 The ``baking'' process is performed by worker threads. By default, one
14969 thread per CPU core is created, but this can be customized. See
14970 @option{--workers} below.
14972 When @option{--ttl} is used, cached entries are automatically deleted
14973 when they have expired.
14975 @item --workers=@var{N}
14976 When @option{--cache} is used, request the allocation of @var{N} worker
14977 threads to ``bake'' archives.
14979 @item --ttl=@var{ttl}
14980 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
14981 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
14982 days, @code{1m} means 1 month, and so on.
14984 This allows the user's Guix to keep substitute information in cache for
14985 @var{ttl}. However, note that @code{guix publish} does not itself
14986 guarantee that the store items it provides will indeed remain available
14987 for as long as @var{ttl}.
14989 Additionally, when @option{--cache} is used, cached entries that have
14990 not been accessed for @var{ttl} and that no longer have a corresponding
14991 item in the store, may be deleted.
14993 @item --negative-ttl=@var{ttl}
14994 Similarly produce @code{Cache-Control} HTTP headers to advertise the
14995 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
14996 which the HTTP 404 code is returned. By default, no negative TTL is
14999 This parameter can help adjust server load and substitute latency by
15000 instructing cooperating clients to be more or less patient when a store
15003 @item --cache-bypass-threshold=@var{size}
15004 When used in conjunction with @option{--cache}, store items smaller than
15005 @var{size} are immediately available, even when they are not yet in
15006 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
15007 for megabytes and so on. The default is @code{10M}.
15009 ``Cache bypass'' allows you to reduce the publication delay for clients
15010 at the expense of possibly additional I/O and CPU use on the server
15011 side: depending on the client access patterns, those store items can end
15012 up being baked several times until a copy is available in cache.
15014 Increasing the threshold may be useful for sites that have few users, or
15015 to guarantee that users get substitutes even for store items that are
15018 @item --nar-path=@var{path}
15019 Use @var{path} as the prefix for the URLs of ``nar'' files
15020 (@pxref{Invoking guix archive, normalized archives}).
15022 By default, nars are served at a URL such as
15023 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
15024 change the @code{/nar} part to @var{path}.
15026 @item --public-key=@var{file}
15027 @itemx --private-key=@var{file}
15028 Use the specific @var{file}s as the public/private key pair used to sign
15029 the store items being published.
15031 The files must correspond to the same key pair (the private key is used
15032 for signing and the public key is merely advertised in the signature
15033 metadata). They must contain keys in the canonical s-expression format
15034 as produced by @command{guix archive --generate-key} (@pxref{Invoking
15035 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
15036 @file{/etc/guix/signing-key.sec} are used.
15038 @item --repl[=@var{port}]
15039 @itemx -r [@var{port}]
15040 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
15041 Reference Manual}) on @var{port} (37146 by default). This is used
15042 primarily for debugging a running @command{guix publish} server.
15045 Enabling @command{guix publish} on Guix System is a one-liner: just
15046 instantiate a @code{guix-publish-service-type} service in the @code{services} field
15047 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
15048 @code{guix-publish-service-type}}).
15050 If you are instead running Guix on a ``foreign distro'', follow these
15055 If your host distro uses the systemd init system:
15058 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
15059 /etc/systemd/system/
15060 # systemctl start guix-publish && systemctl enable guix-publish
15064 If your host distro uses the Upstart init system:
15067 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
15068 # start guix-publish
15072 Otherwise, proceed similarly with your distro's init system.
15075 @node Invoking guix challenge
15076 @section Invoking @command{guix challenge}
15078 @cindex reproducible builds
15079 @cindex verifiable builds
15080 @cindex @command{guix challenge}
15082 Do the binaries provided by this server really correspond to the source
15083 code it claims to build? Is a package build process deterministic?
15084 These are the questions the @command{guix challenge} command attempts to
15087 The former is obviously an important question: Before using a substitute
15088 server (@pxref{Substitutes}), one had better @emph{verify} that it
15089 provides the right binaries, and thus @emph{challenge} it. The latter
15090 is what enables the former: If package builds are deterministic, then
15091 independent builds of the package should yield the exact same result,
15092 bit for bit; if a server provides a binary different from the one
15093 obtained locally, it may be either corrupt or malicious.
15095 We know that the hash that shows up in @file{/gnu/store} file names is
15096 the hash of all the inputs of the process that built the file or
15097 directory---compilers, libraries, build scripts,
15098 etc. (@pxref{Introduction}). Assuming deterministic build processes,
15099 one store file name should map to exactly one build output.
15100 @command{guix challenge} checks whether there is, indeed, a single
15101 mapping by comparing the build outputs of several independent builds of
15102 any given store item.
15104 The command output looks like this:
15108 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org" \
15109 openssl git pius coreutils grep
15110 updating substitutes from 'https://@value{SUBSTITUTE-SERVER-1}'... 100.0%
15111 updating substitutes from 'https://guix.example.org'... 100.0%
15112 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
15113 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15114 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15115 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
15117 /lib/libcrypto.so.1.1
15120 /gnu/store/@dots{}-git-2.5.0 contents differ:
15121 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
15122 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
15123 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
15125 /libexec/git-core/git-fsck
15127 /gnu/store/@dots{}-pius-2.1.1 contents differ:
15128 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15129 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15130 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
15132 /share/man/man1/pius.1.gz
15136 5 store items were analyzed:
15137 - 2 (40.0%) were identical
15138 - 3 (60.0%) differed
15139 - 0 (0.0%) were inconclusive
15143 In this example, @command{guix challenge} queries all the substitute
15144 servers for each of the fives packages specified on the command line.
15145 It then reports those store items for which the servers obtained a
15146 result different from the local build (if it exists) and/or different
15147 from one another; here, the @samp{local hash} lines indicate that a
15148 local build result was available for each of these packages and shows
15151 @cindex non-determinism, in package builds
15152 As an example, @code{guix.example.org} always gets a different answer.
15153 Conversely, @code{@value{SUBSTITUTE-SERVER-1}} agrees with local builds, except in the
15154 case of Git. This might indicate that the build process of Git is
15155 non-deterministic, meaning that its output varies as a function of
15156 various things that Guix does not fully control, in spite of building
15157 packages in isolated environments (@pxref{Features}). Most common
15158 sources of non-determinism include the addition of timestamps in build
15159 results, the inclusion of random numbers, and directory listings sorted
15160 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
15163 To find out what is wrong with this Git binary, the easiest approach is
15167 guix challenge git \
15168 --diff=diffoscope \
15169 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
15172 This automatically invokes @command{diffoscope}, which displays detailed
15173 information about files that differ.
15175 Alternatively, we can do something along these lines (@pxref{Invoking guix
15179 $ wget -q -O - https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-git-2.5.0 \
15180 | lzip -d | guix archive -x /tmp/git
15181 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
15184 This command shows the difference between the files resulting from the
15185 local build, and the files resulting from the build on
15186 @code{@value{SUBSTITUTE-SERVER-1}} (@pxref{Overview, Comparing and Merging Files,,
15187 diffutils, Comparing and Merging Files}). The @command{diff} command
15188 works great for text files. When binary files differ, a better option
15189 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
15190 visualize differences for all kinds of files.
15192 Once you have done that work, you can tell whether the differences are due
15193 to a non-deterministic build process or to a malicious server. We try
15194 hard to remove sources of non-determinism in packages to make it easier
15195 to verify substitutes, but of course, this is a process that
15196 involves not just Guix, but a large part of the free software community.
15197 In the meantime, @command{guix challenge} is one tool to help address
15200 If you are writing packages for Guix, you are encouraged to check
15201 whether @code{@value{SUBSTITUTE-SERVER-1}} and other substitute servers obtain the
15202 same build result as you did with:
15205 guix challenge @var{package}
15208 The general syntax is:
15211 guix challenge @var{options} @var{argument}@dots{}
15215 where @var{argument} is a package specification such as
15216 @code{guile@@2.0} or @code{glibc:debug} or, alternatively, a store file
15217 name as returned, for example, by @command{guix build} or @command{guix
15220 When a difference is found between the hash of a locally-built item and
15221 that of a server-provided substitute, or among substitutes provided by
15222 different servers, the command displays it as in the example above and
15223 its exit code is 2 (other non-zero exit codes denote other kinds of
15226 The one option that matters is:
15230 @item --substitute-urls=@var{urls}
15231 Consider @var{urls} the whitespace-separated list of substitute source
15232 URLs to compare to.
15234 @item --diff=@var{mode}
15235 Upon mismatches, show differences according to @var{mode}, one of:
15238 @item @code{simple} (the default)
15239 Show the list of files that differ.
15241 @item @code{diffoscope}
15242 @itemx @var{command}
15243 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
15244 two directories whose contents do not match.
15246 When @var{command} is an absolute file name, run @var{command} instead
15250 Do not show further details about the differences.
15253 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
15254 downloads the store items from the given substitute servers so that it
15259 Show details about matches (identical contents) in addition to
15260 information about mismatches.
15264 @node Invoking guix copy
15265 @section Invoking @command{guix copy}
15267 @cindex copy, of store items, over SSH
15268 @cindex SSH, copy of store items
15269 @cindex sharing store items across machines
15270 @cindex transferring store items across machines
15271 The @command{guix copy} command copies items from the store of one
15272 machine to that of another machine over a secure shell (SSH)
15273 connection@footnote{This command is available only when Guile-SSH was
15274 found. @xref{Requirements}, for details.}. For example, the following
15275 command copies the @code{coreutils} package, the user's profile, and all
15276 their dependencies over to @var{host}, logged in as @var{user}:
15279 guix copy --to=@var{user}@@@var{host} \
15280 coreutils $(readlink -f ~/.guix-profile)
15283 If some of the items to be copied are already present on @var{host},
15284 they are not actually sent.
15286 The command below retrieves @code{libreoffice} and @code{gimp} from
15287 @var{host}, assuming they are available there:
15290 guix copy --from=@var{host} libreoffice gimp
15293 The SSH connection is established using the Guile-SSH client, which is
15294 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
15295 @file{~/.ssh/config}, and uses the SSH agent for authentication.
15297 The key used to sign items that are sent must be accepted by the remote
15298 machine. Likewise, the key used by the remote machine to sign items you
15299 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
15300 own daemon. @xref{Invoking guix archive}, for more information about
15301 store item authentication.
15303 The general syntax is:
15306 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
15309 You must always specify one of the following options:
15312 @item --to=@var{spec}
15313 @itemx --from=@var{spec}
15314 Specify the host to send to or receive from. @var{spec} must be an SSH
15315 spec such as @code{example.org}, @code{charlie@@example.org}, or
15316 @code{charlie@@example.org:2222}.
15319 The @var{items} can be either package names, such as @code{gimp}, or
15320 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
15322 When specifying the name of a package to send, it is first built if
15323 needed, unless @option{--dry-run} was specified. Common build options
15324 are supported (@pxref{Common Build Options}).
15327 @node Invoking guix container
15328 @section Invoking @command{guix container}
15330 @cindex @command{guix container}
15332 As of version @value{VERSION}, this tool is experimental. The interface
15333 is subject to radical change in the future.
15336 The purpose of @command{guix container} is to manipulate processes
15337 running within an isolated environment, commonly known as a
15338 ``container'', typically created by the @command{guix shell}
15339 (@pxref{Invoking guix shell}) and @command{guix system container}
15340 (@pxref{Invoking guix system}) commands.
15342 The general syntax is:
15345 guix container @var{action} @var{options}@dots{}
15348 @var{action} specifies the operation to perform with a container, and
15349 @var{options} specifies the context-specific arguments for the action.
15351 The following actions are available:
15355 Execute a command within the context of a running container.
15360 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
15363 @var{pid} specifies the process ID of the running container.
15364 @var{program} specifies an executable file name within the root file
15365 system of the container. @var{arguments} are the additional options that
15366 will be passed to @var{program}.
15368 The following command launches an interactive login shell inside a
15369 Guix system container, started by @command{guix system container}, and whose
15370 process ID is 9001:
15373 guix container exec 9001 /run/current-system/profile/bin/bash --login
15376 Note that the @var{pid} cannot be the parent process of a container. It
15377 must be PID 1 of the container or one of its child processes.
15381 @node Invoking guix weather
15382 @section Invoking @command{guix weather}
15384 Occasionally you're grumpy because substitutes are lacking and you end
15385 up building packages by yourself (@pxref{Substitutes}). The
15386 @command{guix weather} command reports on substitute availability on the
15387 specified servers so you can have an idea of whether you'll be grumpy
15388 today. It can sometimes be useful info as a user, but it is primarily
15389 useful to people running @command{guix publish} (@pxref{Invoking guix
15392 @cindex statistics, for substitutes
15393 @cindex availability of substitutes
15394 @cindex substitute availability
15395 @cindex weather, substitute availability
15396 Here's a sample run:
15399 $ guix weather --substitute-urls=https://guix.example.org
15400 computing 5,872 package derivations for x86_64-linux...
15401 looking for 6,128 store items on https://guix.example.org..
15402 updating substitutes from 'https://guix.example.org'... 100.0%
15403 https://guix.example.org
15404 43.4% substitutes available (2,658 out of 6,128)
15405 7,032.5 MiB of nars (compressed)
15406 19,824.2 MiB on disk (uncompressed)
15407 0.030 seconds per request (182.9 seconds in total)
15408 33.5 requests per second
15410 9.8% (342 out of 3,470) of the missing items are queued
15412 x86_64-linux: 518 (59.7%)
15413 i686-linux: 221 (25.5%)
15414 aarch64-linux: 128 (14.8%)
15415 build rate: 23.41 builds per hour
15416 x86_64-linux: 11.16 builds per hour
15417 i686-linux: 6.03 builds per hour
15418 aarch64-linux: 6.41 builds per hour
15421 @cindex continuous integration, statistics
15422 As you can see, it reports the fraction of all the packages for which
15423 substitutes are available on the server---regardless of whether
15424 substitutes are enabled, and regardless of whether this server's signing
15425 key is authorized. It also reports the size of the compressed archives
15426 (``nars'') provided by the server, the size the corresponding store
15427 items occupy in the store (assuming deduplication is turned off), and
15428 the server's throughput. The second part gives continuous integration
15429 (CI) statistics, if the server supports it. In addition, using the
15430 @option{--coverage} option, @command{guix weather} can list ``important''
15431 package substitutes missing on the server (see below).
15433 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
15434 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
15435 challenge}, it ignores signatures on those substitutes, which is
15436 innocuous since the command only gathers statistics and cannot install
15439 The general syntax is:
15442 guix weather @var{options}@dots{} [@var{packages}@dots{}]
15445 When @var{packages} is omitted, @command{guix weather} checks the availability
15446 of substitutes for @emph{all} the packages, or for those specified with
15447 @option{--manifest}; otherwise it only considers the specified packages. It
15448 is also possible to query specific system types with @option{--system}.
15449 @command{guix weather} exits with a non-zero code when the fraction of
15450 available substitutes is below 100%.
15452 The available options are listed below.
15455 @item --substitute-urls=@var{urls}
15456 @var{urls} is the space-separated list of substitute server URLs to
15457 query. When this option is omitted, the default set of substitute
15458 servers is queried.
15460 @item --system=@var{system}
15461 @itemx -s @var{system}
15462 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
15463 option can be repeated, in which case @command{guix weather} will query
15464 substitutes for several system types.
15466 @item --manifest=@var{file}
15467 Instead of querying substitutes for all the packages, only ask for those
15468 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
15469 with the @code{-m} option of @command{guix package} (@pxref{Invoking
15472 This option can be repeated several times, in which case the manifests
15475 @item --coverage[=@var{count}]
15476 @itemx -c [@var{count}]
15477 Report on substitute coverage for packages: list packages with at least
15478 @var{count} dependents (zero by default) for which substitutes are
15479 unavailable. Dependent packages themselves are not listed: if @var{b} depends
15480 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
15481 @var{b} usually lacks substitutes as well. The result looks like this:
15484 $ guix weather --substitute-urls=@value{SUBSTITUTE-URLS} -c 10
15485 computing 8,983 package derivations for x86_64-linux...
15486 looking for 9,343 store items on @value{SUBSTITUTE-URLS}...
15487 updating substitutes from '@value{SUBSTITUTE-URLS}'... 100.0%
15488 @value{SUBSTITUTE-URLS}
15489 64.7% substitutes available (6,047 out of 9,343)
15491 2502 packages are missing from '@value{SUBSTITUTE-URLS}' for 'x86_64-linux', among which:
15492 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
15493 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
15494 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
15498 What this example shows is that @code{kcoreaddons} and presumably the 58
15499 packages that depend on it have no substitutes at
15500 @code{@value{SUBSTITUTE-SERVER-1}}; likewise for @code{qgpgme} and the 46
15501 packages that depend on it.
15503 If you are a Guix developer, or if you are taking care of this build farm,
15504 you'll probably want to have a closer look at these packages: they may simply
15507 @item --display-missing
15508 Display the list of store items for which substitutes are missing.
15511 @node Invoking guix processes
15512 @section Invoking @command{guix processes}
15514 The @command{guix processes} command can be useful to developers and system
15515 administrators, especially on multi-user machines and on build farms: it lists
15516 the current sessions (connections to the daemon), as well as information about
15517 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
15518 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
15519 listed.}. Here's an example of the information it returns:
15522 $ sudo guix processes
15525 ClientCommand: guix shell python
15529 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
15533 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15534 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
15535 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
15536 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
15538 ChildCommand: guix offload x86_64-linux 7200 1 28800
15540 ChildCommand: guix offload x86_64-linux 7200 1 28800
15542 ChildCommand: guix offload x86_64-linux 7200 1 28800
15545 In this example we see that @command{guix-daemon} has three clients:
15546 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
15547 integration tool; their process identifier (PID) is given by the
15548 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
15549 @command{guix-daemon} sub-process of this particular session.
15551 The @code{LockHeld} fields show which store items are currently locked
15552 by this session, which corresponds to store items being built or
15553 substituted (the @code{LockHeld} field is not displayed when
15554 @command{guix processes} is not running as root). Last, by looking at
15555 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
15556 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
15558 The output is in Recutils format so we can use the handy @command{recsel}
15559 command to select sessions of interest (@pxref{Selection Expressions,,,
15560 recutils, GNU recutils manual}). As an example, the command shows the command
15561 line and PID of the client that triggered the build of a Perl package:
15564 $ sudo guix processes | \
15565 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
15567 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15570 Additional options are listed below.
15573 @item --format=@var{format}
15574 @itemx -f @var{format}
15575 Produce output in the specified @var{format}, one of:
15579 The default option. It outputs a set of Session recutils records
15580 that include each @code{ChildProcess} as a field.
15583 Normalize the output records into record sets (@pxref{Record Sets,,,
15584 recutils, GNU recutils manual}). Normalizing into record sets allows
15585 joins across record types. The example below lists the PID of each
15586 @code{ChildProcess} and the associated PID for @code{Session} that
15587 spawned the @code{ChildProcess} where the @code{Session} was started
15588 using @command{guix build}.
15591 $ guix processes --format=normalized | \
15595 -p Session.PID,PID \
15596 -e 'Session.ClientCommand ~ "guix build"'
15609 @node Foreign Architectures
15610 @chapter Foreign Architectures
15612 You can target computers of different CPU architectures when producing
15613 packages (@pxref{Invoking guix package}), packs (@pxref{Invoking guix
15614 pack}) or full systems (@pxref{Invoking guix system}).
15616 GNU Guix supports two distinct mechanisms to target foreign
15622 @uref{https://en.wikipedia.org/wiki/Cross_compiler,cross-compilation}
15625 The native building mechanism which consists in building using the CPU
15626 instruction set of the foreign system you are targeting. It often
15627 requires emulation, using the QEMU program for instance.
15631 * Cross-Compilation:: Cross-compiling for another architecture.
15632 * Native Builds:: Targeting another architecture through native builds.
15635 @node Cross-Compilation
15636 @section Cross-Compilation
15638 @cindex foreign architectures
15639 The commands supporting cross-compilation are proposing the
15640 @option{--list-targets} and @option{--target} options.
15642 The @option{--list-targets} option lists all the supported targets that
15643 can be passed as an argument to @option{--target}.
15646 $ guix build --list-targets
15647 The available targets are:
15649 - aarch64-linux-gnu
15650 - arm-linux-gnueabihf
15654 - mips64el-linux-gnu
15655 - powerpc-linux-gnu
15656 - powerpc64le-linux-gnu
15657 - riscv64-linux-gnu
15659 - x86_64-w64-mingw32
15662 Targets are specified as GNU triplets (@pxref{Specifying Target
15663 Triplets, GNU configuration triplets,, autoconf, Autoconf}).
15665 Those triplets are passed to GCC and the other underlying compilers
15666 possibly involved when building a package, a system image or any other
15670 $ guix build --target=aarch64-linux-gnu hello
15671 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12
15673 $ file /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello
15674 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello: ELF
15675 64-bit LSB executable, ARM aarch64 @dots{}
15678 The major benefit of cross-compilation is that there are no performance
15679 penaly compared to emulation using QEMU. There are however higher risks
15680 that some packages fail to cross-compile because few users are using
15681 this mechanism extensively.
15683 @node Native Builds
15684 @section Native Builds
15686 The commands that support impersonating a specific system have the
15687 @option{--list-systems} and @option{--system} options.
15689 The @option{--list-systems} option lists all the supported systems that
15690 can be passed as an argument to @option{--system}.
15693 $ guix build --list-systems
15694 The available systems are:
15696 - x86_64-linux [current]
15703 - powerpc64le-linux
15706 $ guix build --system=i686-linux hello
15707 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12
15709 $ file /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello
15710 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello: ELF
15711 32-bit LSB executable, Intel 80386 @dots{}
15714 In the above example, the current system is @var{x86_64-linux}. The
15715 @var{hello} package is however built for the @var{i686-linux} system.
15717 This is possible because the @var{i686} CPU instruction set is a subset
15718 of the @var{x86_64}, hence @var{i686} targeting binaries can be run on
15721 Still in the context of the previous example, if picking the
15722 @var{aarch64-linux} system and the @command{guix build
15723 --system=aarch64-linux hello} has to build some derivations, an extra
15724 step might be needed.
15726 The @var{aarch64-linux} targeting binaries cannot directly be run on a
15727 @var{x86_64-linux} system. An emulation layer is requested. The GNU
15728 Guix daemon can take advantage of the Linux kernel
15729 @uref{https://en.wikipedia.org/wiki/Binfmt_misc,binfmt_misc} mechanism
15730 for that. In short, the Linux kernel can defer the execution of a
15731 binary targeting a foreign platform, here @var{aarch64-linux}, to a
15732 userspace program, usually an emulator.
15734 There is a service that registers QEMU as a backend for the
15735 @code{binfmt_misc} mechanism (@pxref{Virtualization Services,
15736 @code{qemu-binfmt-service-type}}). On Debian based foreign
15737 distributions, the alternative would be the @code{qemu-user-static}
15740 If the @code{binfmt_misc} mechanism is not setup correctly, the building
15741 will fail this way:
15744 $ guix build --system=armhf-linux hello --check
15746 @ unsupported-platform /gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv aarch64-linux
15747 while setting up the build environment: a `aarch64-linux' is required to
15748 build `/gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv', but
15749 I am a `x86_64-linux'@dots{}
15752 whereas, with the @code{binfmt_misc} mechanism correctly linked with
15753 QEMU, one can expect to see:
15756 $ guix build --system=armhf-linux hello --check
15757 /gnu/store/13xz4nghg39wpymivlwghy08yzj97hlj-hello-2.12
15760 The main advantage of native building compared to cross-compiling, is
15761 that more packages are likely to build correctly. However it comes at a
15762 price: compilation backed by QEMU is @emph{way slower} than
15763 cross-compilation, because every instruction needs to be emulated.
15765 The availability of substitutes for the architecture targeted by the
15766 @code{--system} option can mitigate this problem. An other way to work
15767 around it is to install GNU Guix on a machine which CPU is supporting
15768 the targeted instruction set, an set it up as an offload machine
15769 (@pxref{Daemon Offload Setup}).
15771 @node System Configuration
15772 @chapter System Configuration
15774 @cindex system configuration
15775 Guix System supports a consistent whole-system configuration
15776 mechanism. By that we mean that all aspects of the global system
15777 configuration---such as the available system services, timezone and
15778 locale settings, user accounts---are declared in a single place. Such
15779 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
15781 One of the advantages of putting all the system configuration under the
15782 control of Guix is that it supports transactional system upgrades, and
15783 makes it possible to roll back to a previous system instantiation,
15784 should something go wrong with the new one (@pxref{Features}). Another
15785 advantage is that it makes it easy to replicate the exact same configuration
15786 across different machines, or at different points in time, without
15787 having to resort to additional administration tools layered on top of
15788 the own tools of the system.
15789 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
15791 This section describes this mechanism. First we focus on the system
15792 administrator's viewpoint---explaining how the system is configured and
15793 instantiated. Then we show how this mechanism can be extended, for
15794 instance to support new system services.
15797 * Using the Configuration System:: Customizing your GNU system.
15798 * operating-system Reference:: Detail of operating-system declarations.
15799 * File Systems:: Configuring file system mounts.
15800 * Mapped Devices:: Block device extra processing.
15801 * Swap Space:: Backing RAM with disk space.
15802 * User Accounts:: Specifying user accounts.
15803 * Keyboard Layout:: How the system interprets key strokes.
15804 * Locales:: Language and cultural convention settings.
15805 * Services:: Specifying system services.
15806 * Setuid Programs:: Programs running with elevated privileges.
15807 * X.509 Certificates:: Authenticating HTTPS servers.
15808 * Name Service Switch:: Configuring libc's name service switch.
15809 * Initial RAM Disk:: Linux-Libre bootstrapping.
15810 * Bootloader Configuration:: Configuring the boot loader.
15811 * Invoking guix system:: Instantiating a system configuration.
15812 * Invoking guix deploy:: Deploying a system configuration to a remote host.
15813 * Running Guix in a VM:: How to run Guix System in a virtual machine.
15814 * Defining Services:: Adding new service definitions.
15817 @node Using the Configuration System
15818 @section Using the Configuration System
15820 The operating system is configured by providing an
15821 @code{operating-system} declaration in a file that can then be passed to
15822 the @command{guix system} command (@pxref{Invoking guix system}). A
15823 simple setup, with the default system services, the default Linux-Libre
15824 kernel, initial RAM disk, and boot loader looks like this:
15826 @findex operating-system
15828 @include os-config-bare-bones.texi
15831 This example should be self-describing. Some of the fields defined
15832 above, such as @code{host-name} and @code{bootloader}, are mandatory.
15833 Others, such as @code{packages} and @code{services}, can be omitted, in
15834 which case they get a default value.
15836 Below we discuss the effect of some of the most important fields
15837 (@pxref{operating-system Reference}, for details about all the available
15838 fields), and how to @dfn{instantiate} the operating system using
15839 @command{guix system}.
15841 @unnumberedsubsec Bootloader
15843 @cindex legacy boot, on Intel machines
15844 @cindex BIOS boot, on Intel machines
15847 The @code{bootloader} field describes the method that will be used to boot
15848 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
15849 mode, as in the example above. However, more recent machines rely instead on
15850 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
15851 the @code{bootloader} field should contain something along these lines:
15854 (bootloader-configuration
15855 (bootloader grub-efi-bootloader)
15856 (targets '("/boot/efi")))
15859 @xref{Bootloader Configuration}, for more information on the available
15860 configuration options.
15862 @unnumberedsubsec Globally-Visible Packages
15864 @vindex %base-packages
15865 The @code{packages} field lists packages that will be globally visible
15866 on the system, for all user accounts---i.e., in every user's @env{PATH}
15867 environment variable---in addition to the per-user profiles
15868 (@pxref{Invoking guix package}). The @code{%base-packages} variable
15869 provides all the tools one would expect for basic user and administrator
15870 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
15871 the @command{mg} lightweight text editor, @command{find}, @command{grep},
15872 etc. The example above adds GNU@tie{}Screen to those,
15873 taken from the @code{(gnu packages screen)}
15874 module (@pxref{Package Modules}). The
15875 @code{(list package output)} syntax can be used to add a specific output
15879 (use-modules (gnu packages))
15880 (use-modules (gnu packages dns))
15884 (packages (cons (list isc-bind "utils")
15888 @findex specification->package
15889 Referring to packages by variable name, like @code{isc-bind} above, has
15890 the advantage of being unambiguous; it also allows typos and such to be
15891 diagnosed right away as ``unbound variables''. The downside is that one
15892 needs to know which module defines which package, and to augment the
15893 @code{use-package-modules} line accordingly. To avoid that, one can use
15894 the @code{specification->package} procedure of the @code{(gnu packages)}
15895 module, which returns the best package for a given name or name and
15899 (use-modules (gnu packages))
15903 (packages (append (map specification->package
15904 '("tcpdump" "htop" "gnupg@@2.0"))
15908 @unnumberedsubsec System Services
15911 @vindex %base-services
15912 The @code{services} field lists @dfn{system services} to be made
15913 available when the system starts (@pxref{Services}).
15914 The @code{operating-system} declaration above specifies that, in
15915 addition to the basic services, we want the OpenSSH secure shell
15916 daemon listening on port 2222 (@pxref{Networking Services,
15917 @code{openssh-service-type}}). Under the hood,
15918 @code{openssh-service-type} arranges so that @command{sshd} is started with the
15919 right command-line options, possibly with supporting configuration files
15920 generated as needed (@pxref{Defining Services}).
15922 @cindex customization, of services
15923 @findex modify-services
15924 Occasionally, instead of using the base services as is, you will want to
15925 customize them. To do this, use @code{modify-services} (@pxref{Service
15926 Reference, @code{modify-services}}) to modify the list.
15928 @anchor{auto-login to TTY} For example, suppose you want to modify
15929 @code{guix-daemon} and Mingetty (the console log-in) in the
15930 @code{%base-services} list (@pxref{Base Services,
15931 @code{%base-services}}). To do that, you can write the following in
15932 your operating system declaration:
15935 (define %my-services
15936 ;; My very own list of services.
15937 (modify-services %base-services
15938 (guix-service-type config =>
15939 (guix-configuration
15941 ;; Fetch substitutes from example.org.
15943 (list "https://example.org/guix"
15944 "https://ci.guix.gnu.org"))))
15945 (mingetty-service-type config =>
15946 (mingetty-configuration
15948 ;; Automatically log in as "guest".
15949 (auto-login "guest")))))
15953 (services %my-services))
15956 This changes the configuration---i.e., the service parameters---of the
15957 @code{guix-service-type} instance, and that of all the
15958 @code{mingetty-service-type} instances in the @code{%base-services} list
15959 (@pxref{Auto-Login to a Specific TTY, see the cookbook for how to
15960 auto-login one user to a specific TTY,, guix-cookbook, GNU Guix Cookbook})).
15961 Observe how this is accomplished: first, we arrange for the original
15962 configuration to be bound to the identifier @code{config} in the
15963 @var{body}, and then we write the @var{body} so that it evaluates to the
15964 desired configuration. In particular, notice how we use @code{inherit}
15965 to create a new configuration which has the same values as the old
15966 configuration, but with a few modifications.
15968 @cindex encrypted disk
15969 The configuration for a typical ``desktop'' usage, with an encrypted
15970 root partition, a swap file on the root partition, the X11 display
15971 server, GNOME and Xfce (users can choose which of these desktop
15972 environments to use at the log-in screen by pressing @kbd{F1}), network
15973 management, power management, and more, would look like this:
15976 @include os-config-desktop.texi
15979 A graphical system with a choice of lightweight window managers
15980 instead of full-blown desktop environments would look like this:
15983 @include os-config-lightweight-desktop.texi
15986 This example refers to the @file{/boot/efi} file system by its UUID,
15987 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
15988 as returned by the @command{blkid} command.
15990 @xref{Desktop Services}, for the exact list of services provided by
15991 @code{%desktop-services}. @xref{X.509 Certificates}, for background
15992 information about the @code{nss-certs} package that is used here.
15994 Again, @code{%desktop-services} is just a list of service objects. If
15995 you want to remove services from there, you can do so using the
15996 procedures for list filtering (@pxref{SRFI-1 Filtering and
15997 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
15998 following expression returns a list that contains all the services in
15999 @code{%desktop-services} minus the Avahi service:
16002 (remove (lambda (service)
16003 (eq? (service-kind service) avahi-service-type))
16007 Alternatively, the @code{modify-services} macro can be used:
16010 (modify-services %desktop-services
16011 (delete avahi-service-type))
16015 @unnumberedsubsec Instantiating the System
16017 Assuming the @code{operating-system} declaration
16018 is stored in the @file{my-system-config.scm}
16019 file, the @command{guix system reconfigure my-system-config.scm} command
16020 instantiates that configuration, and makes it the default GRUB boot
16021 entry (@pxref{Invoking guix system}).
16024 We recommend that you keep this @file{my-system-config.scm} file safe
16025 and under version control to easily track changes to your configuration.
16028 The normal way to change the system configuration is by updating this
16029 file and re-running @command{guix system reconfigure}. One should never
16030 have to touch files in @file{/etc} or to run commands that modify the
16031 system state such as @command{useradd} or @command{grub-install}. In
16032 fact, you must avoid that since that would not only void your warranty
16033 but also prevent you from rolling back to previous versions of your
16034 system, should you ever need to.
16036 @cindex roll-back, of the operating system
16037 Speaking of roll-back, each time you run @command{guix system
16038 reconfigure}, a new @dfn{generation} of the system is created---without
16039 modifying or deleting previous generations. Old system generations get
16040 an entry in the bootloader boot menu, allowing you to boot them in case
16041 something went wrong with the latest generation. Reassuring, no? The
16042 @command{guix system list-generations} command lists the system
16043 generations available on disk. It is also possible to roll back the
16044 system via the commands @command{guix system roll-back} and
16045 @command{guix system switch-generation}.
16047 Although the @command{guix system reconfigure} command will not modify
16048 previous generations, you must take care when the current generation is not
16049 the latest (e.g., after invoking @command{guix system roll-back}), since
16050 the operation might overwrite a later generation (@pxref{Invoking guix
16053 @unnumberedsubsec The Programming Interface
16055 At the Scheme level, the bulk of an @code{operating-system} declaration
16056 is instantiated with the following monadic procedure (@pxref{The Store
16059 @deffn {Monadic Procedure} operating-system-derivation os
16060 Return a derivation that builds @var{os}, an @code{operating-system}
16061 object (@pxref{Derivations}).
16063 The output of the derivation is a single directory that refers to all
16064 the packages, configuration files, and other supporting files needed to
16065 instantiate @var{os}.
16068 This procedure is provided by the @code{(gnu system)} module. Along
16069 with @code{(gnu services)} (@pxref{Services}), this module contains the
16070 guts of Guix System. Make sure to visit it!
16073 @node operating-system Reference
16074 @section @code{operating-system} Reference
16076 This section summarizes all the options available in
16077 @code{operating-system} declarations (@pxref{Using the Configuration
16080 @deftp {Data Type} operating-system
16081 This is the data type representing an operating system configuration.
16082 By that, we mean all the global system configuration, not per-user
16083 configuration (@pxref{Using the Configuration System}).
16086 @item @code{kernel} (default: @code{linux-libre})
16087 The package object of the operating system kernel to
16088 use@footnote{Currently only the Linux-libre kernel is fully supported.
16089 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
16090 available when building a virtual machine disk image.}.
16093 @item @code{hurd} (default: @code{#f})
16094 The package object of the Hurd to be started by the kernel. When this
16095 field is set, produce a GNU/Hurd operating system. In that case,
16096 @code{kernel} must also be set to the @code{gnumach} package---the
16097 microkernel the Hurd runs on.
16100 This feature is experimental and only supported for disk images.
16103 @item @code{kernel-loadable-modules} (default: '())
16104 A list of objects (usually packages) to collect loadable kernel modules
16105 from--e.g. @code{(list ddcci-driver-linux)}.
16107 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
16108 List of strings or gexps representing additional arguments to pass on
16109 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
16111 @item @code{bootloader}
16112 The system bootloader configuration object. @xref{Bootloader Configuration}.
16115 This is the label (a string) as it appears in the bootloader's menu entry.
16116 The default label includes the kernel name and version.
16118 @item @code{keyboard-layout} (default: @code{#f})
16119 This field specifies the keyboard layout to use in the console. It can be
16120 either @code{#f}, in which case the default keyboard layout is used (usually
16121 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
16122 for more information.
16124 This keyboard layout is in effect as soon as the kernel has booted. For
16125 instance, it is the keyboard layout in effect when you type a passphrase if
16126 your root file system is on a @code{luks-device-mapping} mapped device
16127 (@pxref{Mapped Devices}).
16130 This does @emph{not} specify the keyboard layout used by the bootloader, nor
16131 that used by the graphical display server. @xref{Bootloader Configuration},
16132 for information on how to specify the bootloader's keyboard layout. @xref{X
16133 Window}, for information on how to specify the keyboard layout used by the X
16137 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
16139 @cindex initial RAM disk
16140 The list of Linux kernel modules that need to be available in the
16141 initial RAM disk. @xref{Initial RAM Disk}.
16143 @item @code{initrd} (default: @code{base-initrd})
16144 A procedure that returns an initial RAM disk for the Linux
16145 kernel. This field is provided to support low-level customization and
16146 should rarely be needed for casual use. @xref{Initial RAM Disk}.
16148 @item @code{firmware} (default: @code{%base-firmware})
16150 List of firmware packages loadable by the operating system kernel.
16152 The default includes firmware needed for Atheros- and Broadcom-based
16153 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
16154 respectively). @xref{Hardware Considerations}, for more info on
16155 supported hardware.
16157 @item @code{host-name}
16160 @item @code{hosts-file}
16162 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
16163 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
16164 Reference Manual}). The default is a file with entries for
16165 @code{localhost} and @var{host-name}.
16167 @item @code{mapped-devices} (default: @code{'()})
16168 A list of mapped devices. @xref{Mapped Devices}.
16170 @item @code{file-systems}
16171 A list of file systems. @xref{File Systems}.
16173 @item @code{swap-devices} (default: @code{'()})
16174 @cindex swap devices
16175 A list of swap spaces. @xref{Swap Space}.
16177 @item @code{users} (default: @code{%base-user-accounts})
16178 @itemx @code{groups} (default: @code{%base-groups})
16179 List of user accounts and groups. @xref{User Accounts}.
16181 If the @code{users} list lacks a user account with UID@tie{}0, a
16182 ``root'' account with UID@tie{}0 is automatically added.
16184 @item @code{skeletons} (default: @code{(default-skeletons)})
16185 A list of target file name/file-like object tuples (@pxref{G-Expressions,
16186 file-like objects}). These are the skeleton files that will be added to
16187 the home directory of newly-created user accounts.
16189 For instance, a valid value may look like this:
16192 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
16193 (".guile" ,(plain-file "guile"
16194 "(use-modules (ice-9 readline))
16195 (activate-readline)")))
16198 @item @code{issue} (default: @code{%default-issue})
16199 A string denoting the contents of the @file{/etc/issue} file, which is
16200 displayed when users log in on a text console.
16202 @item @code{packages} (default: @code{%base-packages})
16203 A list of packages to be installed in the global profile, which is accessible
16204 at @file{/run/current-system/profile}. Each element is either a package
16205 variable or a package/output tuple. Here's a simple example of both:
16208 (cons* git ; the default "out" output
16209 (list git "send-email") ; another output of git
16210 %base-packages) ; the default set
16213 The default set includes core utilities and it is good practice to
16214 install non-core utilities in user profiles (@pxref{Invoking guix
16217 @item @code{timezone}
16218 A timezone identifying string---e.g., @code{"Europe/Paris"}.
16220 You can run the @command{tzselect} command to find out which timezone
16221 string corresponds to your region. Choosing an invalid timezone name
16222 causes @command{guix system} to fail.
16224 @item @code{locale} (default: @code{"en_US.utf8"})
16225 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
16226 Library Reference Manual}). @xref{Locales}, for more information.
16228 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
16229 The list of locale definitions to be compiled and that may be used at
16230 run time. @xref{Locales}.
16232 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
16233 The list of GNU@tie{}libc packages whose locale data and tools are used
16234 to build the locale definitions. @xref{Locales}, for compatibility
16235 considerations that justify this option.
16237 @item @code{name-service-switch} (default: @code{%default-nss})
16238 Configuration of the libc name service switch (NSS)---a
16239 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
16242 @item @code{services} (default: @code{%base-services})
16243 A list of service objects denoting system services. @xref{Services}.
16245 @cindex essential services
16246 @item @code{essential-services} (default: ...)
16247 The list of ``essential services''---i.e., things like instances of
16248 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
16249 Reference}), which are derived from the operating system definition itself.
16250 As a user you should @emph{never} need to touch this field.
16252 @item @code{pam-services} (default: @code{(base-pam-services)})
16254 @cindex pluggable authentication modules
16255 Linux @dfn{pluggable authentication module} (PAM) services.
16256 @c FIXME: Add xref to PAM services section.
16258 @item @code{setuid-programs} (default: @code{%setuid-programs})
16259 List of @code{<setuid-program>}. @xref{Setuid Programs}, for more
16262 @item @code{sudoers-file} (default: @code{%sudoers-specification})
16263 @cindex sudoers file
16264 The contents of the @file{/etc/sudoers} file as a file-like object
16265 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
16267 This file specifies which users can use the @command{sudo} command, what
16268 they are allowed to do, and what privileges they may gain. The default
16269 is that only @code{root} and members of the @code{wheel} group may use
16274 @deffn {Scheme Syntax} this-operating-system
16275 When used in the @emph{lexical scope} of an operating system field definition,
16276 this identifier resolves to the operating system being defined.
16278 The example below shows how to refer to the operating system being defined in
16279 the definition of the @code{label} field:
16282 (use-modules (gnu) (guix))
16286 (label (package-full-name
16287 (operating-system-kernel this-operating-system))))
16290 It is an error to refer to @code{this-operating-system} outside an operating
16297 @section File Systems
16299 The list of file systems to be mounted is specified in the
16300 @code{file-systems} field of the operating system declaration
16301 (@pxref{Using the Configuration System}). Each file system is declared
16302 using the @code{file-system} form, like this:
16306 (mount-point "/home")
16307 (device "/dev/sda3")
16311 As usual, some of the fields are mandatory---those shown in the example
16312 above---while others can be omitted. These are described below.
16314 @deftp {Data Type} file-system
16315 Objects of this type represent file systems to be mounted. They
16316 contain the following members:
16320 This is a string specifying the type of the file system---e.g.,
16323 @item @code{mount-point}
16324 This designates the place where the file system is to be mounted.
16326 @item @code{device}
16327 This names the ``source'' of the file system. It can be one of three
16328 things: a file system label, a file system UUID, or the name of a
16329 @file{/dev} node. Labels and UUIDs offer a way to refer to file
16330 systems without having to hard-code their actual device
16331 name@footnote{Note that, while it is tempting to use
16332 @file{/dev/disk/by-uuid} and similar device names to achieve the same
16333 result, this is not recommended: These special device nodes are created
16334 by the udev daemon and may be unavailable at the time the device is
16337 @findex file-system-label
16338 File system labels are created using the @code{file-system-label}
16339 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
16340 plain strings. Here's an example of a file system referred to by its
16341 label, as shown by the @command{e2label} command:
16345 (mount-point "/home")
16347 (device (file-system-label "my-home")))
16351 UUIDs are converted from their string representation (as shown by the
16352 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
16353 @code{uuid} form expects 16-byte UUIDs as defined in
16354 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
16355 form of UUID used by the ext2 family of file systems and others, but it
16356 is different from ``UUIDs'' found in FAT file systems, for instance.},
16361 (mount-point "/home")
16363 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16366 When the source of a file system is a mapped device (@pxref{Mapped
16367 Devices}), its @code{device} field @emph{must} refer to the mapped
16368 device name---e.g., @file{"/dev/mapper/root-partition"}.
16369 This is required so that
16370 the system knows that mounting the file system depends on having the
16371 corresponding device mapping established.
16373 @item @code{flags} (default: @code{'()})
16374 This is a list of symbols denoting mount flags. Recognized flags
16375 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
16376 access to special files), @code{no-suid} (ignore setuid and setgid
16377 bits), @code{no-atime} (do not update file access times),
16378 @code{strict-atime} (update file access time), @code{lazy-time} (only
16379 update time on the in-memory version of the file inode), and
16380 @code{no-exec} (disallow program execution).
16381 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
16382 Manual}, for more information on these flags.
16384 @item @code{options} (default: @code{#f})
16385 This is either @code{#f}, or a string denoting mount options passed to
16386 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
16387 Library Reference Manual}, for details and run @command{man 8 mount} for
16388 options for various file systems. Note that the
16389 @code{file-system-options->alist} and @code{alist->file-system-options}
16390 procedures from @code{(gnu system file-systems)} can be used to convert
16391 file system options given as an association list to the string
16392 representation, and vice-versa.
16394 @item @code{mount?} (default: @code{#t})
16395 This value indicates whether to automatically mount the file system when
16396 the system is brought up. When set to @code{#f}, the file system gets
16397 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
16398 is not automatically mounted.
16400 @item @code{needed-for-boot?} (default: @code{#f})
16401 This Boolean value indicates whether the file system is needed when
16402 booting. If that is true, then the file system is mounted when the
16403 initial RAM disk (initrd) is loaded. This is always the case, for
16404 instance, for the root file system.
16406 @item @code{check?} (default: @code{#t})
16407 This Boolean indicates whether the file system should be checked for
16408 errors before being mounted. How and when this happens can be further
16409 adjusted with the following options.
16411 @item @code{skip-check-if-clean?} (default: @code{#t})
16412 When true, this Boolean indicates that a file system check triggered
16413 by @code{check?} may exit early if the file system is marked as
16414 ``clean'', meaning that it was previously correctly unmounted and
16415 should not contain errors.
16417 Setting this to false will always force a full consistency check when
16418 @code{check?} is true. This may take a very long time and is not
16419 recommended on healthy systems---in fact, it may reduce reliability!
16421 Conversely, some primitive file systems like @code{fat} do not keep
16422 track of clean shutdowns and will perform a full scan regardless of the
16423 value of this option.
16425 @item @code{repair} (default: @code{'preen})
16426 When @code{check?} finds errors, it can (try to) repair them and
16427 continue booting. This option controls when and how to do so.
16429 If false, try not to modify the file system at all. Checking certain
16430 file systems like @code{jfs} may still write to the device to replay
16431 the journal. No repairs will be attempted.
16433 If @code{#t}, try to repair any errors found and assume ``yes'' to
16434 all questions. This will fix the most errors, but may be risky.
16436 If @code{'preen}, repair only errors that are safe to fix without
16437 human interaction. What that means is left up to the developers of
16438 each file system and may be equivalent to ``none'' or ``all''.
16440 @item @code{create-mount-point?} (default: @code{#f})
16441 When true, the mount point is created if it does not exist yet.
16443 @item @code{mount-may-fail?} (default: @code{#f})
16444 When true, this indicates that mounting this file system can fail but
16445 that should not be considered an error. This is useful in unusual
16446 cases; an example of this is @code{efivarfs}, a file system that can
16447 only be mounted on EFI/UEFI systems.
16449 @item @code{dependencies} (default: @code{'()})
16450 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
16451 representing file systems that must be mounted or mapped devices that
16452 must be opened before (and unmounted or closed after) this one.
16454 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
16455 a dependency of @file{/sys/fs/cgroup/cpu} and
16456 @file{/sys/fs/cgroup/memory}.
16458 Another example is a file system that depends on a mapped device, for
16459 example for an encrypted partition (@pxref{Mapped Devices}).
16463 @deffn {Scheme Procedure} file-system-label @var{str}
16464 This procedure returns an opaque file system label from @var{str}, a
16468 (file-system-label "home")
16469 @result{} #<file-system-label "home">
16472 File system labels are used to refer to file systems by label rather
16473 than by device name. See above for examples.
16476 The @code{(gnu system file-systems)} exports the following useful
16479 @defvr {Scheme Variable} %base-file-systems
16480 These are essential file systems that are required on normal systems,
16481 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
16482 below). Operating system declarations should always contain at least
16486 @defvr {Scheme Variable} %pseudo-terminal-file-system
16487 This is the file system to be mounted as @file{/dev/pts}. It supports
16488 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
16489 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
16490 Manual}). Pseudo-terminals are used by terminal emulators such as
16494 @defvr {Scheme Variable} %shared-memory-file-system
16495 This file system is mounted as @file{/dev/shm} and is used to support
16496 memory sharing across processes (@pxref{Memory-mapped I/O,
16497 @code{shm_open},, libc, The GNU C Library Reference Manual}).
16500 @defvr {Scheme Variable} %immutable-store
16501 This file system performs a read-only ``bind mount'' of
16502 @file{/gnu/store}, making it read-only for all the users including
16503 @code{root}. This prevents against accidental modification by software
16504 running as @code{root} or by system administrators.
16506 The daemon itself is still able to write to the store: it remounts it
16507 read-write in its own ``name space.''
16510 @defvr {Scheme Variable} %binary-format-file-system
16511 The @code{binfmt_misc} file system, which allows handling of arbitrary
16512 executable file types to be delegated to user space. This requires the
16513 @code{binfmt.ko} kernel module to be loaded.
16516 @defvr {Scheme Variable} %fuse-control-file-system
16517 The @code{fusectl} file system, which allows unprivileged users to mount
16518 and unmount user-space FUSE file systems. This requires the
16519 @code{fuse.ko} kernel module to be loaded.
16522 The @code{(gnu system uuid)} module provides tools to deal with file
16523 system ``unique identifiers'' (UUIDs).
16525 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
16526 Return an opaque UUID (unique identifier) object of the given @var{type}
16527 (a symbol) by parsing @var{str} (a string):
16530 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
16531 @result{} #<<uuid> type: dce bv: @dots{}>
16533 (uuid "1234-ABCD" 'fat)
16534 @result{} #<<uuid> type: fat bv: @dots{}>
16537 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
16538 @code{ntfs}, or one of the commonly found synonyms for these.
16540 UUIDs are another way to unambiguously refer to file systems in
16541 operating system configuration. See the examples above.
16545 @node Btrfs file system
16546 @subsection Btrfs file system
16548 The Btrfs has special features, such as subvolumes, that merit being
16549 explained in more details. The following section attempts to cover
16550 basic as well as complex uses of a Btrfs file system with the Guix
16553 In its simplest usage, a Btrfs file system can be described, for
16558 (mount-point "/home")
16560 (device (file-system-label "my-home")))
16563 The example below is more complex, as it makes use of a Btrfs
16564 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
16565 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
16566 dependency on @code{mapped-devices}):
16570 (device (file-system-label "my-btrfs-pool"))
16573 (options "subvol=rootfs")
16574 (dependencies mapped-devices))
16577 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
16578 top level during the early boot, and rely on their configuration to
16579 refer to the correct subvolume path within that top level. The
16580 bootloaders operating in this way typically produce their configuration
16581 on a running system where the Btrfs partitions are already mounted and
16582 where the subvolume information is readily available. As an example,
16583 @command{grub-mkconfig}, the configuration generator command shipped
16584 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
16585 path of a subvolume.
16587 The Guix System produces a bootloader configuration using the operating
16588 system configuration as its sole input; it is therefore necessary to
16589 extract the subvolume name on which @file{/gnu/store} lives (if any)
16590 from that operating system configuration. To better illustrate,
16591 consider a subvolume named 'rootfs' which contains the root file system
16592 data. In such situation, the GRUB bootloader would only see the top
16593 level of the root Btrfs partition, e.g.:
16597 ├── rootfs (subvolume directory)
16598 ├── gnu (normal directory)
16599 ├── store (normal directory)
16603 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
16604 of the kernel, initrd binaries and any other files referred to in the
16605 GRUB configuration that must be found during the early boot.
16607 The next example shows a nested hierarchy of subvolumes and
16612 ├── rootfs (subvolume)
16613 ├── gnu (normal directory)
16614 ├── store (subvolume)
16618 This scenario would work without mounting the 'store' subvolume.
16619 Mounting 'rootfs' is sufficient, since the subvolume name matches its
16620 intended mount point in the file system hierarchy. Alternatively, the
16621 'store' subvolume could be referred to by setting the @code{subvol}
16622 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
16624 Finally, a more contrived example of nested subvolumes:
16628 ├── root-snapshots (subvolume)
16629 ├── root-current (subvolume)
16630 ├── guix-store (subvolume)
16634 Here, the 'guix-store' subvolume doesn't match its intended mount point,
16635 so it is necessary to mount it. The subvolume must be fully specified,
16636 by passing its file name to the @code{subvol} option. To illustrate,
16637 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
16638 a file system declaration such as:
16642 (device (file-system-label "btrfs-pool-1"))
16643 (mount-point "/gnu/store")
16645 (options "subvol=root-snapshots/root-current/guix-store,\
16646 compress-force=zstd,space_cache=v2"))
16649 @node Mapped Devices
16650 @section Mapped Devices
16652 @cindex device mapping
16653 @cindex mapped devices
16654 The Linux kernel has a notion of @dfn{device mapping}: a block device,
16655 such as a hard disk partition, can be @dfn{mapped} into another device,
16656 usually in @code{/dev/mapper/},
16657 with additional processing over the data that flows through
16658 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
16659 concept of a ``mapped device'' and that of a file system: both boil down
16660 to @emph{translating} input/output operations made on a file to
16661 operations on its backing store. Thus, the Hurd implements mapped
16662 devices, like file systems, using the generic @dfn{translator} mechanism
16663 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
16664 typical example is encryption device mapping: all writes to the mapped
16665 device are encrypted, and all reads are deciphered, transparently.
16666 Guix extends this notion by considering any device or set of devices that
16667 are @dfn{transformed} in some way to create a new device; for instance,
16668 RAID devices are obtained by @dfn{assembling} several other devices, such
16669 as hard disks or partitions, into a new one that behaves as one partition.
16671 Mapped devices are declared using the @code{mapped-device} form,
16672 defined as follows; for examples, see below.
16674 @deftp {Data Type} mapped-device
16675 Objects of this type represent device mappings that will be made when
16676 the system boots up.
16680 This is either a string specifying the name of the block device to be mapped,
16681 such as @code{"/dev/sda3"}, or a list of such strings when several devices
16682 need to be assembled for creating a new one. In case of LVM this is a
16683 string specifying name of the volume group to be mapped.
16686 This string specifies the name of the resulting mapped device. For
16687 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
16688 specifying @code{"my-partition"} leads to the creation of
16689 the @code{"/dev/mapper/my-partition"} device.
16690 For RAID devices of type @code{raid-device-mapping}, the full device name
16691 such as @code{"/dev/md0"} needs to be given.
16692 LVM logical volumes of type @code{lvm-device-mapping} need to
16693 be specified as @code{"VGNAME-LVNAME"}.
16696 This list of strings specifies names of the resulting mapped devices in case
16697 there are several. The format is identical to @var{target}.
16700 This must be a @code{mapped-device-kind} object, which specifies how
16701 @var{source} is mapped to @var{target}.
16705 @defvr {Scheme Variable} luks-device-mapping
16706 This defines LUKS block device encryption using the @command{cryptsetup}
16707 command from the package with the same name. It relies on the
16708 @code{dm-crypt} Linux kernel module.
16711 @defvr {Scheme Variable} raid-device-mapping
16712 This defines a RAID device, which is assembled using the @code{mdadm}
16713 command from the package with the same name. It requires a Linux kernel
16714 module for the appropriate RAID level to be loaded, such as @code{raid456}
16715 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
16718 @cindex LVM, logical volume manager
16719 @defvr {Scheme Variable} lvm-device-mapping
16720 This defines one or more logical volumes for the Linux
16721 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
16722 The volume group is activated by the @command{vgchange} command from the
16723 @code{lvm2} package.
16726 @cindex disk encryption
16728 The following example specifies a mapping from @file{/dev/sda3} to
16729 @file{/dev/mapper/home} using LUKS---the
16730 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
16731 standard mechanism for disk encryption.
16732 The @file{/dev/mapper/home}
16733 device can then be used as the @code{device} of a @code{file-system}
16734 declaration (@pxref{File Systems}).
16738 (source "/dev/sda3")
16740 (type luks-device-mapping))
16743 Alternatively, to become independent of device numbering, one may obtain
16744 the LUKS UUID (@dfn{unique identifier}) of the source device by a
16748 cryptsetup luksUUID /dev/sda3
16751 and use it as follows:
16755 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
16757 (type luks-device-mapping))
16760 @cindex swap encryption
16761 It is also desirable to encrypt swap space, since swap space may contain
16762 sensitive data. One way to accomplish that is to use a swap file in a
16763 file system on a device mapped via LUKS encryption. In this way, the
16764 swap file is encrypted because the entire device is encrypted.
16765 @xref{Swap Space}, or @xref{Preparing for Installation,,Disk
16766 Partitioning}, for an example.
16768 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
16769 may be declared as follows:
16773 (source (list "/dev/sda1" "/dev/sdb1"))
16774 (target "/dev/md0")
16775 (type raid-device-mapping))
16778 The @file{/dev/md0} device can then be used as the @code{device} of a
16779 @code{file-system} declaration (@pxref{File Systems}).
16780 Note that the RAID level need not be given; it is chosen during the
16781 initial creation and formatting of the RAID device and is determined
16782 automatically later.
16784 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
16785 be declared as follows:
16790 (targets (list "vg0-alpha" "vg0-beta"))
16791 (type lvm-device-mapping))
16794 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
16795 then be used as the @code{device} of a @code{file-system} declaration
16796 (@pxref{File Systems}).
16799 @section Swap Space
16802 Swap space, as it is commonly called, is a disk area specifically
16803 designated for paging: the process in charge of memory management
16804 (the Linux kernel or Hurd's default pager) can decide that some memory
16805 pages stored in RAM which belong to a running program but are unused
16806 should be stored on disk instead. It unloads those from the RAM,
16807 freeing up precious fast memory, and writes them to the swap space. If
16808 the program tries to access that very page, the memory management
16809 process loads it back into memory for the program to use.
16811 A common misconception about swap is that it is only useful when small
16812 amounts of RAM are available to the system. However, it should be noted
16813 that kernels often use all available RAM for disk access caching to make
16814 I/O faster, and thus paging out unused portions of program memory will
16815 expand the RAM available for such caching.
16817 For a more detailed description of how memory is managed from the
16818 viewpoint of a monolithic kernel, @xref{Memory
16819 Concepts,,, libc, The GNU C Library Reference Manual}.
16821 The Linux kernel has support for swap partitions and swap files: the
16822 former uses a whole disk partition for paging, whereas the second uses a
16823 file on a file system for that (the file system driver needs to support
16824 it). On a comparable setup, both have the same performance, so one
16825 should consider ease of use when deciding between them. Partitions are
16826 ``simpler'' and do not need file system support, but need to be
16827 allocated at disk formatting time (logical volumes notwithstanding),
16828 whereas files can be allocated and deallocated at any time.
16830 Note that swap space is not zeroed on shutdown, so sensitive data (such
16831 as passwords) may linger on it if it was paged out. As such, you should
16832 consider having your swap reside on an encrypted device (@pxref{Mapped
16835 @deftp {Data Type} swap-space
16836 Objects of this type represent swap spaces. They contain the following
16840 @item @code{target}
16841 The device or file to use, either a UUID, a @code{file-system-label} or
16842 a string, as in the definition of a @code{file-system} (@pxref{File
16845 @item @code{dependencies} (default: @code{'()})
16846 A list of @code{file-system} or @code{mapped-device} objects, upon which
16847 the availability of the space depends. Note that just like for
16848 @code{file-system} objects, dependencies which are needed for boot and
16849 mounted in early userspace are not managed by the Shepherd, and so
16850 automatically filtered out for you.
16852 @item @code{priority} (default: @code{#f})
16853 Only supported by the Linux kernel. Either @code{#f} to disable swap
16854 priority, or an integer between 0 and 32767. The kernel will first use
16855 swap spaces of higher priority when paging, and use same priority spaces
16856 on a round-robin basis. The kernel will use swap spaces without a set
16857 priority after prioritized spaces, and in the order that they appeared in
16860 @item @code{discard?} (default: @code{#f})
16861 Only supported by the Linux kernel. When true, the kernel will notify
16862 the disk controller of discarded pages, for example with the TRIM
16863 operation on Solid State Drives.
16868 Here are some examples:
16871 (swap-space (target (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16874 Use the swap partition with the given UUID@. You can learn the UUID of a
16875 Linux swap partition by running @command{swaplabel @var{device}}, where
16876 @var{device} is the @file{/dev} file name of that partition.
16880 (target (file-system-label "swap"))
16881 (dependencies mapped-devices))
16884 Use the partition with label @code{swap}, which can be found after all
16885 the @var{mapped-devices} mapped devices have been opened. Again, the
16886 @command{swaplabel} command allows you to view and change the label of a
16887 Linux swap partition.
16889 Here's a more involved example with the corresponding @code{file-systems} part
16890 of an @code{operating-system} declaration.
16895 (device (file-system-label "root"))
16899 (device (file-system-label "btrfs"))
16900 (mount-point "/btrfs")
16906 (target "/btrfs/swapfile")
16907 (dependencies (filter (file-system-mount-point-predicate "/btrfs")
16911 Use the file @file{/btrfs/swapfile} as swap space, which depends on the
16912 file system mounted at @file{/btrfs}. Note how we use Guile's filter to
16913 select the file system in an elegant fashion!
16915 @node User Accounts
16916 @section User Accounts
16920 @cindex user accounts
16921 User accounts and groups are entirely managed through the
16922 @code{operating-system} declaration. They are specified with the
16923 @code{user-account} and @code{user-group} forms:
16929 (supplementary-groups '("wheel" ;allow use of sudo, etc.
16930 "audio" ;sound card
16931 "video" ;video devices such as webcams
16932 "cdrom")) ;the good ol' CD-ROM
16933 (comment "Bob's sister"))
16936 Here's a user account that uses a different shell and a custom home
16937 directory (the default would be @file{"/home/bob"}):
16943 (comment "Alice's bro")
16944 (shell (file-append zsh "/bin/zsh"))
16945 (home-directory "/home/robert"))
16948 When booting or upon completion of @command{guix system reconfigure},
16949 the system ensures that only the user accounts and groups specified in
16950 the @code{operating-system} declaration exist, and with the specified
16951 properties. Thus, account or group creations or modifications made by
16952 directly invoking commands such as @command{useradd} are lost upon
16953 reconfiguration or reboot. This ensures that the system remains exactly
16956 @deftp {Data Type} user-account
16957 Objects of this type represent user accounts. The following members may
16962 The name of the user account.
16966 This is the name (a string) or identifier (a number) of the user group
16967 this account belongs to.
16969 @item @code{supplementary-groups} (default: @code{'()})
16970 Optionally, this can be defined as a list of group names that this
16971 account belongs to.
16973 @item @code{uid} (default: @code{#f})
16974 This is the user ID for this account (a number), or @code{#f}. In the
16975 latter case, a number is automatically chosen by the system when the
16976 account is created.
16978 @item @code{comment} (default: @code{""})
16979 A comment about the account, such as the account owner's full name.
16981 Note that, for non-system accounts, users are free to change their real
16982 name as it appears in @file{/etc/passwd} using the @command{chfn}
16983 command. When they do, their choice prevails over the system
16984 administrator's choice; reconfiguring does @emph{not} change their name.
16986 @item @code{home-directory}
16987 This is the name of the home directory for the account.
16989 @item @code{create-home-directory?} (default: @code{#t})
16990 Indicates whether the home directory of this account should be created
16991 if it does not exist yet.
16993 @item @code{shell} (default: Bash)
16994 This is a G-expression denoting the file name of a program to be used as
16995 the shell (@pxref{G-Expressions}). For example, you would refer to the
16996 Bash executable like this:
16999 (file-append bash "/bin/bash")
17003 ... and to the Zsh executable like that:
17006 (file-append zsh "/bin/zsh")
17009 @item @code{system?} (default: @code{#f})
17010 This Boolean value indicates whether the account is a ``system''
17011 account. System accounts are sometimes treated specially; for instance,
17012 graphical login managers do not list them.
17014 @anchor{user-account-password}
17015 @cindex password, for user accounts
17016 @item @code{password} (default: @code{#f})
17017 You would normally leave this field to @code{#f}, initialize user
17018 passwords as @code{root} with the @command{passwd} command, and then let
17019 users change it with @command{passwd}. Passwords set with
17020 @command{passwd} are of course preserved across reboot and
17023 If you @emph{do} want to set an initial password for an account, then
17024 this field must contain the encrypted password, as a string. You can use the
17025 @code{crypt} procedure for this purpose:
17032 ;; Specify a SHA-512-hashed initial password.
17033 (password (crypt "InitialPassword!" "$6$abc")))
17037 The hash of this initial password will be available in a file in
17038 @file{/gnu/store}, readable by all the users, so this method must be used with
17042 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
17043 more information on password encryption, and @ref{Encryption,,, guile, GNU
17044 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
17050 User group declarations are even simpler:
17053 (user-group (name "students"))
17056 @deftp {Data Type} user-group
17057 This type is for, well, user groups. There are just a few fields:
17061 The name of the group.
17063 @item @code{id} (default: @code{#f})
17064 The group identifier (a number). If @code{#f}, a new number is
17065 automatically allocated when the group is created.
17067 @item @code{system?} (default: @code{#f})
17068 This Boolean value indicates whether the group is a ``system'' group.
17069 System groups have low numerical IDs.
17071 @item @code{password} (default: @code{#f})
17072 What, user groups can have a password? Well, apparently yes. Unless
17073 @code{#f}, this field specifies the password of the group.
17078 For convenience, a variable lists all the basic user groups one may
17081 @defvr {Scheme Variable} %base-groups
17082 This is the list of basic user groups that users and/or packages expect
17083 to be present on the system. This includes groups such as ``root'',
17084 ``wheel'', and ``users'', as well as groups used to control access to
17085 specific devices such as ``audio'', ``disk'', and ``cdrom''.
17088 @defvr {Scheme Variable} %base-user-accounts
17089 This is the list of basic system accounts that programs may expect to
17090 find on a GNU/Linux system, such as the ``nobody'' account.
17092 Note that the ``root'' account is not included here. It is a
17093 special-case and is automatically added whether or not it is specified.
17096 @node Keyboard Layout
17097 @section Keyboard Layout
17099 @cindex keyboard layout
17101 To specify what each key of your keyboard does, you need to tell the operating
17102 system what @dfn{keyboard layout} you want to use. The default, when nothing
17103 is specified, is the US English QWERTY layout for 105-key PC keyboards.
17104 However, German speakers will usually prefer the German QWERTZ layout, French
17105 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
17106 or bépo, and they might even want to further customize the effect of some of
17107 the keys. This section explains how to get that done.
17109 @cindex keyboard layout, definition
17110 There are three components that will want to know about your keyboard layout:
17114 The @emph{bootloader} may want to know what keyboard layout you want to use
17115 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
17116 you want, for instance, to make sure that you can type the passphrase of your
17117 encrypted root partition using the right layout.
17120 The @emph{operating system kernel}, Linux, will need that so that the console
17121 is properly configured (@pxref{operating-system Reference,
17122 @code{keyboard-layout}}).
17125 The @emph{graphical display server}, usually Xorg, also has its own idea of
17126 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
17129 Guix allows you to configure all three separately but, fortunately, it allows
17130 you to share the same keyboard layout for all three components.
17132 @cindex XKB, keyboard layouts
17133 Keyboard layouts are represented by records created by the
17134 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
17135 the X Keyboard extension (XKB), each layout has four attributes: a name (often
17136 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
17137 optional variant name, an optional keyboard model name, and a possibly empty
17138 list of additional options. In most cases the layout name is all you care
17141 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
17142 [#:model] [#:options '()]
17143 Return a new keyboard layout with the given @var{name} and @var{variant}.
17145 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
17146 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
17147 @code{xkeyboard-config} package for valid options.
17150 Here are a few examples:
17153 ;; The German QWERTZ layout. Here we assume a standard
17154 ;; "pc105" keyboard model.
17155 (keyboard-layout "de")
17157 ;; The bépo variant of the French layout.
17158 (keyboard-layout "fr" "bepo")
17160 ;; The Catalan layout.
17161 (keyboard-layout "es" "cat")
17163 ;; Arabic layout with "Alt-Shift" to switch to US layout.
17164 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
17166 ;; The Latin American Spanish layout. In addition, the
17167 ;; "Caps Lock" key is used as an additional "Ctrl" key,
17168 ;; and the "Menu" key is used as a "Compose" key to enter
17169 ;; accented letters.
17170 (keyboard-layout "latam"
17171 #:options '("ctrl:nocaps" "compose:menu"))
17173 ;; The Russian layout for a ThinkPad keyboard.
17174 (keyboard-layout "ru" #:model "thinkpad")
17176 ;; The "US international" layout, which is the US layout plus
17177 ;; dead keys to enter accented characters. This is for an
17178 ;; Apple MacBook keyboard.
17179 (keyboard-layout "us" "intl" #:model "macbook78")
17182 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
17183 for a complete list of supported layouts, variants, and models.
17185 @cindex keyboard layout, configuration
17186 Let's say you want your system to use the Turkish keyboard layout throughout
17187 your system---bootloader, console, and Xorg. Here's what your system
17188 configuration would look like:
17190 @findex set-xorg-configuration
17192 ;; Using the Turkish layout for the bootloader, the console,
17197 (keyboard-layout (keyboard-layout "tr")) ;for the console
17198 (bootloader (bootloader-configuration
17199 (bootloader grub-efi-bootloader)
17200 (targets '("/boot/efi"))
17201 (keyboard-layout keyboard-layout))) ;for GRUB
17202 (services (cons (set-xorg-configuration
17203 (xorg-configuration ;for Xorg
17204 (keyboard-layout keyboard-layout)))
17205 %desktop-services)))
17208 In the example above, for GRUB and for Xorg, we just refer to the
17209 @code{keyboard-layout} field defined above, but we could just as well refer to
17210 a different layout. The @code{set-xorg-configuration} procedure communicates
17211 the desired Xorg configuration to the graphical log-in manager, by default
17214 We've discussed how to specify the @emph{default} keyboard layout of your
17215 system when it starts, but you can also adjust it at run time:
17219 If you're using GNOME, its settings panel has a ``Region & Language'' entry
17220 where you can select one or more keyboard layouts.
17223 Under Xorg, the @command{setxkbmap} command (from the same-named package)
17224 allows you to change the current layout. For example, this is how you would
17225 change the layout to US Dvorak:
17228 setxkbmap us dvorak
17232 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
17233 console. However, note that @code{loadkeys} does @emph{not} use the XKB
17234 keyboard layout categorization described above. The command below loads the
17235 French bépo layout:
17246 A @dfn{locale} defines cultural conventions for a particular language
17247 and region of the world (@pxref{Locales,,, libc, The GNU C Library
17248 Reference Manual}). Each locale has a name that typically has the form
17249 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
17250 @code{fr_LU.utf8} designates the locale for the French language, with
17251 cultural conventions from Luxembourg, and using the UTF-8 encoding.
17253 @cindex locale definition
17254 Usually, you will want to specify the default locale for the machine
17255 using the @code{locale} field of the @code{operating-system} declaration
17256 (@pxref{operating-system Reference, @code{locale}}).
17258 The selected locale is automatically added to the @dfn{locale
17259 definitions} known to the system if needed, with its codeset inferred
17260 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
17261 @code{UTF-8} codeset. Additional locale definitions can be specified in
17262 the @code{locale-definitions} slot of @code{operating-system}---this is
17263 useful, for instance, if the codeset could not be inferred from the
17264 locale name. The default set of locale definitions includes some widely
17265 used locales, but not all the available locales, in order to save space.
17267 For instance, to add the North Frisian locale for Germany, the value of
17271 (cons (locale-definition
17272 (name "fy_DE.utf8") (source "fy_DE"))
17273 %default-locale-definitions)
17276 Likewise, to save space, one might want @code{locale-definitions} to
17277 list only the locales that are actually used, as in:
17280 (list (locale-definition
17281 (name "ja_JP.eucjp") (source "ja_JP")
17282 (charset "EUC-JP")))
17286 The compiled locale definitions are available at
17287 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
17288 version, which is the default location where the GNU@tie{}libc provided
17289 by Guix looks for locale data. This can be overridden using the
17290 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
17291 @env{LOCPATH} and locale packages}).
17293 The @code{locale-definition} form is provided by the @code{(gnu system
17294 locale)} module. Details are given below.
17296 @deftp {Data Type} locale-definition
17297 This is the data type of a locale definition.
17302 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
17303 Reference Manual}, for more information on locale names.
17305 @item @code{source}
17306 The name of the source for that locale. This is typically the
17307 @code{@var{language}_@var{territory}} part of the locale name.
17309 @item @code{charset} (default: @code{"UTF-8"})
17310 The ``character set'' or ``code set'' for that locale,
17311 @uref{https://www.iana.org/assignments/character-sets, as defined by
17317 @defvr {Scheme Variable} %default-locale-definitions
17318 A list of commonly used UTF-8 locales, used as the default
17319 value of the @code{locale-definitions} field of @code{operating-system}
17322 @cindex locale name
17323 @cindex normalized codeset in locale names
17324 These locale definitions use the @dfn{normalized codeset} for the part
17325 that follows the dot in the name (@pxref{Using gettextized software,
17326 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
17327 instance it has @code{uk_UA.utf8} but @emph{not}, say,
17328 @code{uk_UA.UTF-8}.
17331 @subsection Locale Data Compatibility Considerations
17333 @cindex incompatibility, of locale data
17334 @code{operating-system} declarations provide a @code{locale-libcs} field
17335 to specify the GNU@tie{}libc packages that are used to compile locale
17336 declarations (@pxref{operating-system Reference}). ``Why would I
17337 care?'', you may ask. Well, it turns out that the binary format of
17338 locale data is occasionally incompatible from one libc version to
17341 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
17342 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
17343 For instance, a program linked against libc version 2.21 is unable to
17344 read locale data produced with libc 2.22; worse, that program
17345 @emph{aborts} instead of simply ignoring the incompatible locale
17346 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
17347 the incompatible locale data, which is already an improvement.}.
17348 Similarly, a program linked against libc 2.22 can read most, but not
17349 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
17350 data is incompatible); thus calls to @code{setlocale} may fail, but
17351 programs will not abort.
17353 The ``problem'' with Guix is that users have a lot of freedom: They can
17354 choose whether and when to upgrade software in their profiles, and might
17355 be using a libc version different from the one the system administrator
17356 used to build the system-wide locale data.
17358 Fortunately, unprivileged users can also install their own locale data
17359 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
17360 @env{GUIX_LOCPATH} and locale packages}).
17362 Still, it is best if the system-wide locale data at
17363 @file{/run/current-system/locale} is built for all the libc versions
17364 actually in use on the system, so that all the programs can access
17365 it---this is especially crucial on a multi-user system. To do that, the
17366 administrator can specify several libc packages in the
17367 @code{locale-libcs} field of @code{operating-system}:
17370 (use-package-modules base)
17374 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
17377 This example would lead to a system containing locale definitions for
17378 both libc 2.21 and the current version of libc in
17379 @file{/run/current-system/locale}.
17385 @cindex system services
17386 An important part of preparing an @code{operating-system} declaration is
17387 listing @dfn{system services} and their configuration (@pxref{Using the
17388 Configuration System}). System services are typically daemons launched
17389 when the system boots, or other actions needed at that time---e.g.,
17390 configuring network access.
17392 Guix has a broad definition of ``service'' (@pxref{Service
17393 Composition}), but many services are managed by the GNU@tie{}Shepherd
17394 (@pxref{Shepherd Services}). On a running system, the @command{herd}
17395 command allows you to list the available services, show their status,
17396 start and stop them, or do other specific operations (@pxref{Jump
17397 Start,,, shepherd, The GNU Shepherd Manual}). For example:
17403 The above command, run as @code{root}, lists the currently defined
17404 services. The @command{herd doc} command shows a synopsis of the given
17405 service and its associated actions:
17409 Run libc's name service cache daemon (nscd).
17411 # herd doc nscd action invalidate
17412 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
17415 The @command{start}, @command{stop}, and @command{restart} sub-commands
17416 have the effect you would expect. For instance, the commands below stop
17417 the nscd service and restart the Xorg display server:
17421 Service nscd has been stopped.
17422 # herd restart xorg-server
17423 Service xorg-server has been stopped.
17424 Service xorg-server has been started.
17427 The following sections document the available services, starting with
17428 the core services, that may be used in an @code{operating-system}
17432 * Base Services:: Essential system services.
17433 * Scheduled Job Execution:: The mcron service.
17434 * Log Rotation:: The rottlog service.
17435 * Networking Setup:: Setting up network interfaces.
17436 * Networking Services:: Firewall, SSH daemon, etc.
17437 * Unattended Upgrades:: Automated system upgrades.
17438 * X Window:: Graphical display.
17439 * Printing Services:: Local and remote printer support.
17440 * Desktop Services:: D-Bus and desktop services.
17441 * Sound Services:: ALSA and Pulseaudio services.
17442 * Database Services:: SQL databases, key-value stores, etc.
17443 * Mail Services:: IMAP, POP3, SMTP, and all that.
17444 * Messaging Services:: Messaging services.
17445 * Telephony Services:: Telephony services.
17446 * File-Sharing Services:: File-sharing services.
17447 * Monitoring Services:: Monitoring services.
17448 * Kerberos Services:: Kerberos services.
17449 * LDAP Services:: LDAP services.
17450 * Web Services:: Web servers.
17451 * Certificate Services:: TLS certificates via Let's Encrypt.
17452 * DNS Services:: DNS daemons.
17453 * VPN Services:: VPN daemons.
17454 * Network File System:: NFS related services.
17455 * Continuous Integration:: Cuirass and Laminar services.
17456 * Power Management Services:: Extending battery life.
17457 * Audio Services:: The MPD.
17458 * Virtualization Services:: Virtualization services.
17459 * Version Control Services:: Providing remote access to Git repositories.
17460 * Game Services:: Game servers.
17461 * PAM Mount Service:: Service to mount volumes when logging in.
17462 * Guix Services:: Services relating specifically to Guix.
17463 * Linux Services:: Services tied to the Linux kernel.
17464 * Hurd Services:: Services specific for a Hurd System.
17465 * Miscellaneous Services:: Other services.
17468 @node Base Services
17469 @subsection Base Services
17471 The @code{(gnu services base)} module provides definitions for the basic
17472 services that one expects from the system. The services exported by
17473 this module are listed below.
17475 @defvr {Scheme Variable} %base-services
17476 This variable contains a list of basic services (@pxref{Service Types
17477 and Services}, for more information on service objects) one would
17478 expect from the system: a login service (mingetty) on each tty, syslogd,
17479 the libc name service cache daemon (nscd), the udev device manager, and
17482 This is the default value of the @code{services} field of
17483 @code{operating-system} declarations. Usually, when customizing a
17484 system, you will want to append services to @code{%base-services}, like
17488 (append (list (service avahi-service-type)
17489 (service openssh-service-type))
17494 @defvr {Scheme Variable} special-files-service-type
17495 This is the service that sets up ``special files'' such as
17496 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
17498 The value associated with @code{special-files-service-type} services
17499 must be a list of tuples where the first element is the ``special file''
17500 and the second element is its target. By default it is:
17502 @cindex @file{/bin/sh}
17503 @cindex @file{sh}, in @file{/bin}
17505 `(("/bin/sh" ,(file-append bash "/bin/sh")))
17508 @cindex @file{/usr/bin/env}
17509 @cindex @file{env}, in @file{/usr/bin}
17510 If you want to add, say, @code{/usr/bin/env} to your system, you can
17514 `(("/bin/sh" ,(file-append bash "/bin/sh"))
17515 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
17518 Since this is part of @code{%base-services}, you can use
17519 @code{modify-services} to customize the set of special files
17520 (@pxref{Service Reference, @code{modify-services}}). But the simple way
17521 to add a special file is @i{via} the @code{extra-special-file} procedure
17525 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
17526 Use @var{target} as the ``special file'' @var{file}.
17528 For example, adding the following lines to the @code{services} field of
17529 your operating system declaration leads to a @file{/usr/bin/env}
17533 (extra-special-file "/usr/bin/env"
17534 (file-append coreutils "/bin/env"))
17538 @deffn {Scheme Procedure} host-name-service @var{name}
17539 Return a service that sets the host name to @var{name}.
17542 @defvr {Scheme Variable} console-font-service-type
17543 Install the given fonts on the specified ttys (fonts are per
17544 virtual console on the kernel Linux). The value of this service is a list of
17545 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
17546 package or any valid argument to @command{setfont}, as in this example:
17549 `(("tty1" . "LatGrkCyr-8x16")
17550 ("tty2" . ,(file-append
17552 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
17553 ("tty3" . ,(file-append
17555 "/share/consolefonts/ter-132n"))) ; for HDPI
17559 @deffn {Scheme Procedure} login-service @var{config}
17560 Return a service to run login according to @var{config}, a
17561 @code{<login-configuration>} object, which specifies the message of the day,
17562 among other things.
17565 @deftp {Data Type} login-configuration
17566 This is the data type representing the configuration of login.
17571 @cindex message of the day
17572 A file-like object containing the ``message of the day''.
17574 @item @code{allow-empty-passwords?} (default: @code{#t})
17575 Allow empty passwords by default so that first-time users can log in when
17576 the 'root' account has just been created.
17581 @deffn {Scheme Procedure} mingetty-service @var{config}
17582 Return a service to run mingetty according to @var{config}, a
17583 @code{<mingetty-configuration>} object, which specifies the tty to run, among
17587 @deftp {Data Type} mingetty-configuration
17588 This is the data type representing the configuration of Mingetty, which
17589 provides the default implementation of virtual console log-in.
17594 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
17596 @item @code{auto-login} (default: @code{#f})
17597 When true, this field must be a string denoting the user name under
17598 which the system automatically logs in. When it is @code{#f}, a
17599 user name and password must be entered to log in.
17601 @item @code{login-program} (default: @code{#f})
17602 This must be either @code{#f}, in which case the default log-in program
17603 is used (@command{login} from the Shadow tool suite), or a gexp denoting
17604 the name of the log-in program.
17606 @item @code{login-pause?} (default: @code{#f})
17607 When set to @code{#t} in conjunction with @var{auto-login}, the user
17608 will have to press a key before the log-in shell is launched.
17610 @item @code{clear-on-logout?} (default: @code{#t})
17611 When set to @code{#t}, the screen will be cleared after logout.
17613 @item @code{mingetty} (default: @var{mingetty})
17614 The Mingetty package to use.
17619 @deffn {Scheme Procedure} agetty-service @var{config}
17620 Return a service to run agetty according to @var{config}, an
17621 @code{<agetty-configuration>} object, which specifies the tty to run,
17622 among other things.
17625 @deftp {Data Type} agetty-configuration
17626 This is the data type representing the configuration of agetty, which
17627 implements virtual and serial console log-in. See the @code{agetty(8)}
17628 man page for more information.
17633 The name of the console this agetty runs on, as a string---e.g.,
17634 @code{"ttyS0"}. This argument is optional, it will default to
17635 a reasonable default serial port used by the kernel Linux.
17637 For this, if there is a value for an option @code{agetty.tty} in the kernel
17638 command line, agetty will extract the device name of the serial port
17639 from it and use that.
17641 If not and if there is a value for an option @code{console} with a tty in
17642 the Linux command line, agetty will extract the device name of the
17643 serial port from it and use that.
17645 In both cases, agetty will leave the other serial device settings
17646 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
17649 @item @code{baud-rate} (default: @code{#f})
17650 A string containing a comma-separated list of one or more baud rates, in
17653 @item @code{term} (default: @code{#f})
17654 A string containing the value used for the @env{TERM} environment
17657 @item @code{eight-bits?} (default: @code{#f})
17658 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
17661 @item @code{auto-login} (default: @code{#f})
17662 When passed a login name, as a string, the specified user will be logged
17663 in automatically without prompting for their login name or password.
17665 @item @code{no-reset?} (default: @code{#f})
17666 When @code{#t}, don't reset terminal cflags (control modes).
17668 @item @code{host} (default: @code{#f})
17669 This accepts a string containing the ``login_host'', which will be written
17670 into the @file{/var/run/utmpx} file.
17672 @item @code{remote?} (default: @code{#f})
17673 When set to @code{#t} in conjunction with @var{host}, this will add an
17674 @code{-r} fakehost option to the command line of the login program
17675 specified in @var{login-program}.
17677 @item @code{flow-control?} (default: @code{#f})
17678 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
17680 @item @code{no-issue?} (default: @code{#f})
17681 When set to @code{#t}, the contents of the @file{/etc/issue} file will
17682 not be displayed before presenting the login prompt.
17684 @item @code{init-string} (default: @code{#f})
17685 This accepts a string that will be sent to the tty or modem before
17686 sending anything else. It can be used to initialize a modem.
17688 @item @code{no-clear?} (default: @code{#f})
17689 When set to @code{#t}, agetty will not clear the screen before showing
17692 @item @code{login-program} (default: (file-append shadow "/bin/login"))
17693 This must be either a gexp denoting the name of a log-in program, or
17694 unset, in which case the default value is the @command{login} from the
17697 @item @code{local-line} (default: @code{#f})
17698 Control the CLOCAL line flag. This accepts one of three symbols as
17699 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
17700 the default value chosen by agetty is @code{'auto}.
17702 @item @code{extract-baud?} (default: @code{#f})
17703 When set to @code{#t}, instruct agetty to try to extract the baud rate
17704 from the status messages produced by certain types of modems.
17706 @item @code{skip-login?} (default: @code{#f})
17707 When set to @code{#t}, do not prompt the user for a login name. This
17708 can be used with @var{login-program} field to use non-standard login
17711 @item @code{no-newline?} (default: @code{#f})
17712 When set to @code{#t}, do not print a newline before printing the
17713 @file{/etc/issue} file.
17715 @c Is this dangerous only when used with login-program, or always?
17716 @item @code{login-options} (default: @code{#f})
17717 This option accepts a string containing options that are passed to the
17718 login program. When used with the @var{login-program}, be aware that a
17719 malicious user could try to enter a login name containing embedded
17720 options that could be parsed by the login program.
17722 @item @code{login-pause} (default: @code{#f})
17723 When set to @code{#t}, wait for any key before showing the login prompt.
17724 This can be used in conjunction with @var{auto-login} to save memory by
17725 lazily spawning shells.
17727 @item @code{chroot} (default: @code{#f})
17728 Change root to the specified directory. This option accepts a directory
17731 @item @code{hangup?} (default: @code{#f})
17732 Use the Linux system call @code{vhangup} to do a virtual hangup of the
17733 specified terminal.
17735 @item @code{keep-baud?} (default: @code{#f})
17736 When set to @code{#t}, try to keep the existing baud rate. The baud
17737 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
17740 @item @code{timeout} (default: @code{#f})
17741 When set to an integer value, terminate if no user name could be read
17742 within @var{timeout} seconds.
17744 @item @code{detect-case?} (default: @code{#f})
17745 When set to @code{#t}, turn on support for detecting an uppercase-only
17746 terminal. This setting will detect a login name containing only
17747 uppercase letters as indicating an uppercase-only terminal and turn on
17748 some upper-to-lower case conversions. Note that this will not support
17749 Unicode characters.
17751 @item @code{wait-cr?} (default: @code{#f})
17752 When set to @code{#t}, wait for the user or modem to send a
17753 carriage-return or linefeed character before displaying
17754 @file{/etc/issue} or login prompt. This is typically used with the
17755 @var{init-string} option.
17757 @item @code{no-hints?} (default: @code{#f})
17758 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
17761 @item @code{no-hostname?} (default: @code{#f})
17762 By default, the hostname is printed. When this option is set to
17763 @code{#t}, no hostname will be shown at all.
17765 @item @code{long-hostname?} (default: @code{#f})
17766 By default, the hostname is only printed until the first dot. When this
17767 option is set to @code{#t}, the fully qualified hostname by
17768 @code{gethostname} or @code{getaddrinfo} is shown.
17770 @item @code{erase-characters} (default: @code{#f})
17771 This option accepts a string of additional characters that should be
17772 interpreted as backspace when the user types their login name.
17774 @item @code{kill-characters} (default: @code{#f})
17775 This option accepts a string that should be interpreted to mean ``ignore
17776 all previous characters'' (also called a ``kill'' character) when the user
17777 types their login name.
17779 @item @code{chdir} (default: @code{#f})
17780 This option accepts, as a string, a directory path that will be changed
17783 @item @code{delay} (default: @code{#f})
17784 This options accepts, as an integer, the number of seconds to sleep
17785 before opening the tty and displaying the login prompt.
17787 @item @code{nice} (default: @code{#f})
17788 This option accepts, as an integer, the nice value with which to run the
17789 @command{login} program.
17791 @item @code{extra-options} (default: @code{'()})
17792 This option provides an ``escape hatch'' for the user to provide arbitrary
17793 command-line arguments to @command{agetty} as a list of strings.
17795 @item @code{shepherd-requirement} (default: @code{'()})
17796 The option can be used to provides extra shepherd requirements (for example
17797 @code{'syslogd}) to the respective @code{'term-}* shepherd service.
17802 @deffn {Scheme Procedure} kmscon-service-type @var{config}
17803 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
17804 according to @var{config}, a @code{<kmscon-configuration>} object, which
17805 specifies the tty to run, among other things.
17808 @deftp {Data Type} kmscon-configuration
17809 This is the data type representing the configuration of Kmscon, which
17810 implements virtual console log-in.
17814 @item @code{virtual-terminal}
17815 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
17817 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
17818 A gexp denoting the name of the log-in program. The default log-in program is
17819 @command{login} from the Shadow tool suite.
17821 @item @code{login-arguments} (default: @code{'("-p")})
17822 A list of arguments to pass to @command{login}.
17824 @item @code{auto-login} (default: @code{#f})
17825 When passed a login name, as a string, the specified user will be logged
17826 in automatically without prompting for their login name or password.
17828 @item @code{hardware-acceleration?} (default: #f)
17829 Whether to use hardware acceleration.
17831 @item @code{font-engine} (default: @code{"pango"})
17832 Font engine used in Kmscon.
17834 @item @code{font-size} (default: @code{12})
17835 Font size used in Kmscon.
17837 @item @code{keyboard-layout} (default: @code{#f})
17838 If this is @code{#f}, Kmscon uses the default keyboard layout---usually US
17839 English (``qwerty'') for a 105-key PC keyboard.
17841 Otherwise this must be a @code{keyboard-layout} object specifying the
17842 keyboard layout. @xref{Keyboard Layout}, for more information on how to
17843 specify the keyboard layout.
17845 @item @code{kmscon} (default: @var{kmscon})
17846 The Kmscon package to use.
17851 @cindex name service cache daemon
17853 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
17854 [#:name-services '()]
17855 Return a service that runs the libc name service cache daemon (nscd) with the
17856 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
17857 Service Switch}, for an example.
17859 For convenience, the Shepherd service for nscd provides the following actions:
17863 @cindex cache invalidation, nscd
17864 @cindex nscd, cache invalidation
17865 This invalidate the given cache. For instance, running:
17868 herd invalidate nscd hosts
17872 invalidates the host name lookup cache of nscd.
17875 Running @command{herd statistics nscd} displays information about nscd usage
17881 @defvr {Scheme Variable} %nscd-default-configuration
17882 This is the default @code{<nscd-configuration>} value (see below) used
17883 by @code{nscd-service}. It uses the caches defined by
17884 @code{%nscd-default-caches}; see below.
17887 @deftp {Data Type} nscd-configuration
17888 This is the data type representing the name service cache daemon (nscd)
17893 @item @code{name-services} (default: @code{'()})
17894 List of packages denoting @dfn{name services} that must be visible to
17895 the nscd---e.g., @code{(list @var{nss-mdns})}.
17897 @item @code{glibc} (default: @var{glibc})
17898 Package object denoting the GNU C Library providing the @command{nscd}
17901 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
17902 Name of the nscd log file. This is where debugging output goes when
17903 @code{debug-level} is strictly positive.
17905 @item @code{debug-level} (default: @code{0})
17906 Integer denoting the debugging levels. Higher numbers mean that more
17907 debugging output is logged.
17909 @item @code{caches} (default: @code{%nscd-default-caches})
17910 List of @code{<nscd-cache>} objects denoting things to be cached; see
17916 @deftp {Data Type} nscd-cache
17917 Data type representing a cache database of nscd and its parameters.
17921 @item @code{database}
17922 This is a symbol representing the name of the database to be cached.
17923 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
17924 @code{services}, which designate the corresponding NSS database
17925 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
17927 @item @code{positive-time-to-live}
17928 @itemx @code{negative-time-to-live} (default: @code{20})
17929 A number representing the number of seconds during which a positive or
17930 negative lookup result remains in cache.
17932 @item @code{check-files?} (default: @code{#t})
17933 Whether to check for updates of the files corresponding to
17936 For instance, when @var{database} is @code{hosts}, setting this flag
17937 instructs nscd to check for updates in @file{/etc/hosts} and to take
17940 @item @code{persistent?} (default: @code{#t})
17941 Whether the cache should be stored persistently on disk.
17943 @item @code{shared?} (default: @code{#t})
17944 Whether the cache should be shared among users.
17946 @item @code{max-database-size} (default: 32@tie{}MiB)
17947 Maximum size in bytes of the database cache.
17949 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
17950 @c settings, so leave them out.
17955 @defvr {Scheme Variable} %nscd-default-caches
17956 List of @code{<nscd-cache>} objects used by default by
17957 @code{nscd-configuration} (see above).
17959 It enables persistent and aggressive caching of service and host name
17960 lookups. The latter provides better host name lookup performance,
17961 resilience in the face of unreliable name servers, and also better
17962 privacy---often the result of host name lookups is in local cache, so
17963 external name servers do not even need to be queried.
17966 @anchor{syslog-configuration-type}
17969 @deftp {Data Type} syslog-configuration
17970 This data type represents the configuration of the syslog daemon.
17973 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
17974 The syslog daemon to use.
17976 @item @code{config-file} (default: @code{%default-syslog.conf})
17977 The syslog configuration file to use.
17982 @anchor{syslog-service}
17984 @deffn {Scheme Procedure} syslog-service @var{config}
17985 Return a service that runs a syslog daemon according to @var{config}.
17987 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
17988 information on the configuration file syntax.
17991 @defvr {Scheme Variable} guix-service-type
17992 This is the type of the service that runs the build daemon,
17993 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
17994 @code{guix-configuration} record as described below.
17997 @anchor{guix-configuration-type}
17998 @deftp {Data Type} guix-configuration
17999 This data type represents the configuration of the Guix build daemon.
18000 @xref{Invoking guix-daemon}, for more information.
18003 @item @code{guix} (default: @var{guix})
18004 The Guix package to use.
18006 @item @code{build-group} (default: @code{"guixbuild"})
18007 Name of the group for build user accounts.
18009 @item @code{build-accounts} (default: @code{10})
18010 Number of build user accounts to create.
18012 @item @code{authorize-key?} (default: @code{#t})
18013 @cindex substitutes, authorization thereof
18014 Whether to authorize the substitute keys listed in
18015 @code{authorized-keys}---by default that of
18016 @code{@value{SUBSTITUTE-SERVER-1}} and
18017 @code{@value{SUBSTITUTE-SERVER-2}}
18018 (@pxref{Substitutes}).
18020 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
18021 changed by invoking @command{guix archive --authorize}. You must
18022 instead adjust @code{guix-configuration} as you wish and reconfigure the
18023 system. This ensures that your operating system configuration file is
18027 When booting or reconfiguring to a system where @code{authorize-key?}
18028 is true, the existing @file{/etc/guix/acl} file is backed up as
18029 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
18030 file. This is to facilitate migration from earlier versions, which
18031 allowed for in-place modifications to @file{/etc/guix/acl}.
18034 @vindex %default-authorized-guix-keys
18035 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
18036 The list of authorized key files for archive imports, as a list of
18037 string-valued gexps (@pxref{Invoking guix archive}). By default, it
18038 contains that of @code{@value{SUBSTITUTE-SERVER-1}} and
18039 @code{@value{SUBSTITUTE-SERVER-2}} (@pxref{Substitutes}). See
18040 @code{substitute-urls} below for an example on how to change it.
18042 @item @code{use-substitutes?} (default: @code{#t})
18043 Whether to use substitutes.
18045 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
18046 The list of URLs where to look for substitutes by default.
18048 Suppose you would like to fetch substitutes from @code{guix.example.org}
18049 in addition to @code{@value{SUBSTITUTE-SERVER-1}}. You will need to do
18050 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
18051 and (2) authorize its signing key, having done appropriate checks
18052 (@pxref{Substitute Server Authorization}). The configuration below does
18056 (guix-configuration
18058 (append (list "https://guix.example.org")
18059 %default-substitute-urls))
18061 (append (list (local-file "./guix.example.org-key.pub"))
18062 %default-authorized-guix-keys)))
18065 This example assumes that the file @file{./guix.example.org-key.pub}
18066 contains the public key that @code{guix.example.org} uses to sign
18069 @item @code{generate-substitute-key?} (default: @code{#t})
18070 Whether to generate a @dfn{substitute key pair} under
18071 @file{/etc/guix/signing-key.pub} and @file{/etc/guix/signing-key.sec} if
18072 there is not already one.
18074 This key pair is used when exporting store items, for instance with
18075 @command{guix publish} (@pxref{Invoking guix publish}) or @command{guix
18076 archive} (@pxref{Invoking guix archive}). Generating a key pair takes a
18077 few seconds when enough entropy is available and is only done once; you
18078 might want to turn it off for instance in a virtual machine that does
18079 not need it and where the extra boot time is a problem.
18081 @item @code{max-silent-time} (default: @code{0})
18082 @itemx @code{timeout} (default: @code{0})
18083 The number of seconds of silence and the number of seconds of activity,
18084 respectively, after which a build process times out. A value of zero
18085 disables the timeout.
18087 @item @code{log-compression} (default: @code{'gzip})
18088 The type of compression used for build logs---one of @code{gzip},
18089 @code{bzip2}, or @code{none}.
18091 @item @code{discover?} (default: @code{#f})
18092 Whether to discover substitute servers on the local network using mDNS
18095 @item @code{extra-options} (default: @code{'()})
18096 List of extra command-line options for @command{guix-daemon}.
18098 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
18099 File where @command{guix-daemon}'s standard output and standard error
18102 @cindex HTTP proxy, for @code{guix-daemon}
18103 @cindex proxy, for @code{guix-daemon} HTTP access
18104 @item @code{http-proxy} (default: @code{#f})
18105 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
18106 derivations and substitutes.
18108 It is also possible to change the daemon's proxy at run time through the
18109 @code{set-http-proxy} action, which restarts it:
18112 herd set-http-proxy guix-daemon http://localhost:8118
18115 To clear the proxy settings, run:
18118 herd set-http-proxy guix-daemon
18121 @item @code{tmpdir} (default: @code{#f})
18122 A directory path where the @command{guix-daemon} will perform builds.
18127 @deftp {Data Type} guix-extension
18129 This data type represents the parameters of the Guix build daemon that
18130 are extendable. This is the type of the object that must be used within
18131 a guix service extension.
18132 @xref{Service Composition}, for more information.
18135 @item @code{authorized-keys} (default: @code{'()})
18136 A list of file-like objects where each element contains a public key.
18138 @item @code{substitute-urls} (default: @code{'()})
18139 A list of strings where each element is a substitute URL.
18141 @item @code{chroot-directories} (default: @code{'()})
18142 A list of file-like objects or strings pointing to additional directories the build daemon can use.
18146 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
18147 Run @var{udev}, which populates the @file{/dev} directory dynamically.
18148 udev rules can be provided as a list of files through the @var{rules}
18149 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
18150 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
18151 creation of such rule files.
18153 The @command{herd rules udev} command, as root, returns the name of the
18154 directory containing all the active udev rules.
18157 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
18158 Return a udev-rule file named @var{file-name} containing the rules
18159 defined by the @var{contents} literal.
18161 In the following example, a rule for a USB device is defined to be
18162 stored in the file @file{90-usb-thing.rules}. The rule runs a script
18163 upon detecting a USB device with a given product identifier.
18166 (define %example-udev-rule
18168 "90-usb-thing.rules"
18169 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
18170 "ATTR@{product@}==\"Example\", "
18171 "RUN+=\"/path/to/script\"")))
18175 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
18176 [#:groups @var{groups}]
18177 Return a service that extends @code{udev-service-type } with @var{rules}
18178 and @code{account-service-type} with @var{groups} as system groups.
18179 This works by creating a singleton service type
18180 @code{@var{name}-udev-rules}, of which the returned service is an
18183 Here we show how it can be used to extend @code{udev-service-type} with the
18184 previously defined rule @code{%example-udev-rule}.
18190 (cons (udev-rules-service 'usb-thing %example-udev-rule)
18191 %desktop-services)))
18195 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
18196 Return a udev file named @var{file-name} containing the rules defined
18197 within @var{file}, a file-like object.
18199 The following example showcases how we can use an existing rule file.
18202 (use-modules (guix download) ;for url-fetch
18203 (guix packages) ;for origin
18206 (define %android-udev-rules
18208 "51-android-udev.rules"
18209 (let ((version "20170910"))
18212 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
18213 "android-udev-rules/" version "/51-android.rules"))
18215 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
18219 Additionally, Guix package definitions can be included in @var{rules} in
18220 order to extend the udev rules with the definitions found under their
18221 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
18222 @var{file->udev-rule} example, we could have used the
18223 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
18224 packages android)} module.
18226 The following example shows how to use the @var{android-udev-rules}
18227 package so that the Android tool @command{adb} can detect devices
18228 without root privileges. It also details how to create the
18229 @code{adbusers} group, which is required for the proper functioning of
18230 the rules defined within the @code{android-udev-rules} package. To
18231 create such a group, we must define it both as part of the
18232 @code{supplementary-groups} of our @code{user-account} declaration, as
18233 well as in the @var{groups} of the @code{udev-rules-service} procedure.
18236 (use-modules (gnu packages android) ;for android-udev-rules
18237 (gnu system shadow) ;for user-group
18242 (users (cons (user-account
18244 (supplementary-groups
18245 '("adbusers" ;for adb
18246 "wheel" "netdev" "audio" "video")))))
18249 (cons (udev-rules-service 'android android-udev-rules
18250 #:groups '("adbusers"))
18251 %desktop-services)))
18254 @defvr {Scheme Variable} urandom-seed-service-type
18255 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
18256 when rebooting. It also tries to seed @file{/dev/urandom} from
18257 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
18261 @defvr {Scheme Variable} %random-seed-file
18262 This is the name of the file where some random bytes are saved by
18263 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
18264 It defaults to @file{/var/lib/random-seed}.
18269 @defvr {Scheme Variable} gpm-service-type
18270 This is the type of the service that runs GPM, the @dfn{general-purpose
18271 mouse daemon}, which provides mouse support to the Linux console. GPM
18272 allows users to use the mouse in the console, notably to select, copy,
18275 The value for services of this type must be a @code{gpm-configuration}
18276 (see below). This service is not part of @code{%base-services}.
18279 @deftp {Data Type} gpm-configuration
18280 Data type representing the configuration of GPM.
18283 @item @code{options} (default: @code{%default-gpm-options})
18284 Command-line options passed to @command{gpm}. The default set of
18285 options instruct @command{gpm} to listen to mouse events on
18286 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
18289 @item @code{gpm} (default: @code{gpm})
18290 The GPM package to use.
18295 @anchor{guix-publish-service-type}
18296 @deffn {Scheme Variable} guix-publish-service-type
18297 This is the service type for @command{guix publish} (@pxref{Invoking
18298 guix publish}). Its value must be a @code{guix-publish-configuration}
18299 object, as described below.
18301 This assumes that @file{/etc/guix} already contains a signing key pair as
18302 created by @command{guix archive --generate-key} (@pxref{Invoking guix
18303 archive}). If that is not the case, the service will fail to start.
18306 @deftp {Data Type} guix-publish-configuration
18307 Data type representing the configuration of the @code{guix publish}
18311 @item @code{guix} (default: @code{guix})
18312 The Guix package to use.
18314 @item @code{port} (default: @code{80})
18315 The TCP port to listen for connections.
18317 @item @code{host} (default: @code{"localhost"})
18318 The host (and thus, network interface) to listen to. Use
18319 @code{"0.0.0.0"} to listen on all the network interfaces.
18321 @item @code{advertise?} (default: @code{#f})
18322 When true, advertise the service on the local network @i{via} the DNS-SD
18323 protocol, using Avahi.
18325 This allows neighboring Guix devices with discovery on (see
18326 @code{guix-configuration} above) to discover this @command{guix publish}
18327 instance and to automatically download substitutes from it.
18329 @item @code{compression} (default: @code{'(("gzip" 3) ("zstd" 3))})
18330 This is a list of compression method/level tuple used when compressing
18331 substitutes. For example, to compress all substitutes with @emph{both} lzip
18332 at level 7 and gzip at level 9, write:
18335 '(("lzip" 7) ("gzip" 9))
18338 Level 9 achieves the best compression ratio at the expense of increased CPU
18339 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
18340 publish}, for more information on the available compression methods and
18341 the tradeoffs involved.
18343 An empty list disables compression altogether.
18345 @item @code{nar-path} (default: @code{"nar"})
18346 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
18347 publish, @option{--nar-path}}, for details.
18349 @item @code{cache} (default: @code{#f})
18350 When it is @code{#f}, disable caching and instead generate archives on
18351 demand. Otherwise, this should be the name of a directory---e.g.,
18352 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
18353 archives and meta-data ready to be sent. @xref{Invoking guix publish,
18354 @option{--cache}}, for more information on the tradeoffs involved.
18356 @item @code{workers} (default: @code{#f})
18357 When it is an integer, this is the number of worker threads used for
18358 caching; when @code{#f}, the number of processors is used.
18359 @xref{Invoking guix publish, @option{--workers}}, for more information.
18361 @item @code{cache-bypass-threshold} (default: 10 MiB)
18362 When @code{cache} is true, this is the maximum size in bytes of a store
18363 item for which @command{guix publish} may bypass its cache in case of a
18364 cache miss. @xref{Invoking guix publish,
18365 @option{--cache-bypass-threshold}}, for more information.
18367 @item @code{ttl} (default: @code{#f})
18368 When it is an integer, this denotes the @dfn{time-to-live} in seconds
18369 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
18370 for more information.
18372 @item @code{negative-ttl} (default: @code{#f})
18373 When it is an integer, this denotes the @dfn{time-to-live} in
18374 seconds for the negative lookups. @xref{Invoking guix publish,
18375 @option{--negative-ttl}}, for more information.
18379 @anchor{rngd-service}
18380 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
18381 [#:device "/dev/hwrng"]
18382 Return a service that runs the @command{rngd} program from @var{rng-tools}
18383 to add @var{device} to the kernel's entropy pool. The service will fail if
18384 @var{device} does not exist.
18387 @anchor{pam-limits-service}
18388 @cindex session limits
18394 @cindex open file descriptors
18395 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
18397 Return a service that installs a configuration file for the
18398 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
18399 @code{pam_limits} module}. The procedure optionally takes a list of
18400 @code{pam-limits-entry} values, which can be used to specify
18401 @code{ulimit} limits and @code{nice} priority limits to user sessions.
18403 The following limits definition sets two hard and soft limits for all
18404 login sessions of users in the @code{realtime} group:
18407 (pam-limits-service
18409 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
18410 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
18413 The first entry increases the maximum realtime priority for
18414 non-privileged processes; the second entry lifts any restriction of the
18415 maximum address space that can be locked in memory. These settings are
18416 commonly used for real-time audio systems.
18418 Another useful example is raising the maximum number of open file
18419 descriptors that can be used:
18422 (pam-limits-service
18424 (pam-limits-entry "*" 'both 'nofile 100000)))
18427 In the above example, the asterisk means the limit should apply to any
18428 user. It is important to ensure the chosen value doesn't exceed the
18429 maximum system value visible in the @file{/proc/sys/fs/file-max} file,
18430 else the users would be prevented from login in. For more information
18431 about the Pluggable Authentication Module (PAM) limits, refer to the
18432 @samp{pam_limits} man page from the @code{linux-pam} package.
18435 @defvr {Scheme Variable} greetd-service-type
18436 @uref{https://git.sr.ht/~kennylevinsen/greetd, @code{greetd}} is a minimal and
18437 flexible login manager daemon, that makes no assumptions about what you
18440 If you can run it from your shell in a TTY, greetd can start it. If it
18441 can be taught to speak a simple JSON-based IPC protocol, then it can be
18444 @code{greetd-service-type} provides necessary infrastructure for logging
18445 in users, including:
18449 @code{greetd} PAM service
18452 Special variation of @code{pam-mount} to mount @code{XDG_RUNTIME_DIR}
18455 Here is example of switching from @code{mingetty-service-type} to
18456 @code{greetd-service-type}, and how different terminals could be:
18460 (modify-services %base-services
18461 ;; greetd-service-type provides "greetd" PAM service
18462 (delete login-service-type)
18463 ;; and can be used in place of mingetty-service-type
18464 (delete mingetty-service-type))
18466 (service greetd-service-type
18467 (greetd-configuration
18470 ;; we can make any terminal active by default
18471 (greetd-terminal-configuration (terminal-vt "1") (terminal-switch #t))
18472 ;; we can make environment without XDG_RUNTIME_DIR set
18473 ;; even provide our own environment variables
18474 (greetd-terminal-configuration
18476 (default-session-command
18477 (greetd-agreety-session
18478 (extra-env '(("MY_VAR" . "1")))
18480 ;; we can use different shell instead of default bash
18481 (greetd-terminal-configuration
18483 (default-session-command
18484 (greetd-agreety-session (command (file-append zsh "/bin/zsh")))))
18485 ;; we can use any other executable command as greeter
18486 (greetd-terminal-configuration
18488 (default-session-command (program-file "my-noop-greeter" #~(exit))))
18489 (greetd-terminal-configuration (terminal-vt "5"))
18490 (greetd-terminal-configuration (terminal-vt "6"))))))
18491 ;; mingetty-service-type can be used in parallel
18492 ;; if needed to do so, do not (delete login-service-type)
18493 ;; as illustrated above
18494 #| (service mingetty-service-type (mingetty-configuration (tty "tty8"))) |#))
18498 @deftp {Data Type} greetd-configuration
18499 Configuration record for the @code{greetd-service-type}.
18503 A file-like object containing the ``message of the day''.
18505 @item @code{allow-empty-passwords?} (default: @code{#t})
18506 Allow empty passwords by default so that first-time users can log in when
18507 the 'root' account has just been created.
18509 @item @code{terminals} (default: @code{'()})
18510 List of @code{greetd-terminal-configuration} per terminal for which
18511 @code{greetd} should be started.
18515 @deftp {Data Type} greetd-terminal-configuration
18516 Configuration record for per terminal greetd daemon service.
18519 @item @code{greetd} (default: @code{greetd})
18520 The greetd package to use.
18522 @item @code{config-file-name}
18523 Configuration file name to use for greetd daemon. Generally, autogenerated
18524 derivation based on @code{terminal-vt} value.
18526 @item @code{log-file-name}
18527 Log file name to use for greetd daemon. Generally, autogenerated
18528 name based on @code{terminal-vt} value.
18530 @item @code{terminal-vt} (default: @samp{"7"})
18531 The VT to run on. Use of a specific VT with appropriate conflict avoidance
18534 @item @code{terminal-switch} (default: @code{#f})
18535 Make this terminal active on start of @code{greetd}.
18537 @item @code{default-session-user} (default: @samp{"greeter"})
18538 The user to use for running the greeter.
18540 @item @code{default-session-command} (default: @code{(greetd-agreety-session)})
18541 Can be either instance of @code{greetd-agreety-session} configuration or
18542 @code{gexp->script} like object to use as greeter.
18547 @deftp {Data Type} greetd-agreety-session
18548 Configuration record for the agreety greetd greeter.
18551 @item @code{agreety} (default: @code{greetd})
18552 The package with @command{/bin/agreety} command.
18554 @item @code{command} (default: @code{(file-append bash "/bin/bash")})
18555 Command to be started by @command{/bin/agreety} on successful login.
18557 @item @code{command-args} (default: @code{'("-l")})
18558 Command arguments to pass to command.
18560 @item @code{extra-env} (default: @code{'()})
18561 Extra environment variables to set on login.
18563 @item @code{xdg-env?} (default: @code{#t})
18564 If true @code{XDG_RUNTIME_DIR} and @code{XDG_SESSION_TYPE} will be set
18565 before starting command. One should note that, @code{extra-env} variables
18566 are set right after mentioned variables, so that they can be overriden.
18571 @node Scheduled Job Execution
18572 @subsection Scheduled Job Execution
18576 @cindex scheduling jobs
18577 The @code{(gnu services mcron)} module provides an interface to
18578 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
18579 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
18580 Unix @command{cron} daemon; the main difference is that it is
18581 implemented in Guile Scheme, which provides a lot of flexibility when
18582 specifying the scheduling of jobs and their actions.
18584 The example below defines an operating system that runs the
18585 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
18586 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
18587 well as the @command{mkid} command on behalf of an unprivileged user
18588 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
18589 gexps to introduce job definitions that are passed to mcron
18590 (@pxref{G-Expressions}).
18593 (use-modules (guix) (gnu) (gnu services mcron))
18594 (use-package-modules base idutils)
18596 (define updatedb-job
18597 ;; Run 'updatedb' at 3AM every day. Here we write the
18598 ;; job's action as a Scheme procedure.
18599 #~(job '(next-hour '(3))
18601 (execl (string-append #$findutils "/bin/updatedb")
18603 "--prunepaths=/tmp /var/tmp /gnu/store"))
18606 (define garbage-collector-job
18607 ;; Collect garbage 5 minutes after midnight every day.
18608 ;; The job's action is a shell command.
18609 #~(job "5 0 * * *" ;Vixie cron syntax
18612 (define idutils-job
18613 ;; Update the index database as user "charlie" at 12:15PM
18614 ;; and 19:15PM. This runs from the user's home directory.
18615 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
18616 (string-append #$idutils "/bin/mkid src")
18622 ;; %BASE-SERVICES already includes an instance of
18623 ;; 'mcron-service-type', which we extend with additional
18624 ;; jobs using 'simple-service'.
18625 (services (cons (simple-service 'my-cron-jobs
18627 (list garbage-collector-job
18634 When providing the action of a job specification as a procedure, you
18635 should provide an explicit name for the job via the optional 3rd
18636 argument as done in the @code{updatedb-job} example above. Otherwise,
18637 the job would appear as ``Lambda function'' in the output of
18638 @command{herd schedule mcron}, which is not nearly descriptive enough!
18641 For more complex jobs defined in Scheme where you need control over the top
18642 level, for instance to introduce a @code{use-modules} form, you can move your
18643 code to a separate program using the @code{program-file} procedure of the
18644 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
18648 (define %battery-alert-job
18649 ;; Beep when the battery percentage falls below %MIN-LEVEL.
18651 '(next-minute (range 0 60 1))
18653 "battery-alert.scm"
18654 (with-imported-modules (source-module-closure
18655 '((guix build utils)))
18657 (use-modules (guix build utils)
18660 (ice-9 textual-ports)
18663 (define %min-level 20)
18665 (setenv "LC_ALL" "C") ;ensure English output
18666 (and-let* ((input-pipe (open-pipe*
18668 #$(file-append acpi "/bin/acpi")))
18669 (output (get-string-all input-pipe))
18670 (m (string-match "Discharging, ([0-9]+)%" output))
18671 (level (string->number (match:substring m 1)))
18672 ((< level %min-level)))
18673 (format #t "warning: Battery level is low (~a%)~%" level)
18674 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
18677 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
18678 for more information on mcron job specifications. Below is the
18679 reference of the mcron service.
18681 On a running system, you can use the @code{schedule} action of the service to
18682 visualize the mcron jobs that will be executed next:
18685 # herd schedule mcron
18689 The example above lists the next five tasks that will be executed, but you can
18690 also specify the number of tasks to display:
18693 # herd schedule mcron 10
18696 @defvr {Scheme Variable} mcron-service-type
18697 This is the type of the @code{mcron} service, whose value is an
18698 @code{mcron-configuration} object.
18700 This service type can be the target of a service extension that provides
18701 additional job specifications (@pxref{Service Composition}). In other
18702 words, it is possible to define services that provide additional mcron
18706 @deftp {Data Type} mcron-configuration
18707 Data type representing the configuration of mcron.
18710 @item @code{mcron} (default: @var{mcron})
18711 The mcron package to use.
18714 This is a list of gexps (@pxref{G-Expressions}), where each gexp
18715 corresponds to an mcron job specification (@pxref{Syntax, mcron job
18716 specifications,, mcron, GNU@tie{}mcron}).
18722 @subsection Log Rotation
18725 @cindex log rotation
18727 Log files such as those found in @file{/var/log} tend to grow endlessly,
18728 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
18729 their contents in separate files, possibly compressed. The @code{(gnu
18730 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
18731 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
18733 This service is part of @code{%base-services}, and thus enabled by
18734 default, with the default settings, for commonly encountered log files.
18735 The example below shows how to extend it with an additional
18736 @dfn{rotation}, should you need to do that (usually, services that
18737 produce log files already take care of that):
18740 (use-modules (guix) (gnu))
18741 (use-service-modules admin)
18743 (define my-log-files
18744 ;; Log files that I want to rotate.
18745 '("/var/log/something.log" "/var/log/another.log"))
18749 (services (cons (simple-service 'rotate-my-stuff
18750 rottlog-service-type
18751 (list (log-rotation
18753 (files my-log-files))))
18757 @defvr {Scheme Variable} rottlog-service-type
18758 This is the type of the Rottlog service, whose value is a
18759 @code{rottlog-configuration} object.
18761 Other services can extend this one with new @code{log-rotation} objects
18762 (see below), thereby augmenting the set of files to be rotated.
18764 This service type can define mcron jobs (@pxref{Scheduled Job
18765 Execution}) to run the rottlog service.
18768 @deftp {Data Type} rottlog-configuration
18769 Data type representing the configuration of rottlog.
18772 @item @code{rottlog} (default: @code{rottlog})
18773 The Rottlog package to use.
18775 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
18776 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
18777 rottlog, GNU Rot[t]log Manual}).
18779 @item @code{rotations} (default: @code{%default-rotations})
18780 A list of @code{log-rotation} objects as defined below.
18783 This is a list of gexps where each gexp corresponds to an mcron job
18784 specification (@pxref{Scheduled Job Execution}).
18788 @deftp {Data Type} log-rotation
18789 Data type representing the rotation of a group of log files.
18791 Taking an example from the Rottlog manual (@pxref{Period Related File
18792 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
18798 (files '("/var/log/apache/*"))
18799 (options '("storedir apache-archives"
18805 The list of fields is as follows:
18808 @item @code{frequency} (default: @code{'weekly})
18809 The log rotation frequency, a symbol.
18812 The list of files or file glob patterns to rotate.
18814 @vindex %default-log-rotation-options
18815 @item @code{options} (default: @code{%default-log-rotation-options})
18816 The list of rottlog options for this rotation (@pxref{Configuration
18817 parameters,,, rottlog, GNU Rot[t]log Manual}).
18819 @item @code{post-rotate} (default: @code{#f})
18820 Either @code{#f} or a gexp to execute once the rotation has completed.
18824 @defvr {Scheme Variable} %default-rotations
18825 Specifies weekly rotation of @code{%rotated-files} and of
18826 @file{/var/log/guix-daemon.log}.
18829 @defvr {Scheme Variable} %rotated-files
18830 The list of syslog-controlled files to be rotated. By default it is:
18831 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
18832 "/var/log/maillog")}.
18835 Some log files just need to be deleted periodically once they are old,
18836 without any other criterion and without any archival step. This is the
18837 case of build logs stored by @command{guix-daemon} under
18838 @file{/var/log/guix/drvs} (@pxref{Invoking guix-daemon}). The
18839 @code{log-cleanup} service addresses this use case. For example,
18840 @code{%base-services} (@pxref{Base Services}) includes the following:
18843 ;; Periodically delete old build logs.
18844 (service log-cleanup-service-type
18845 (log-cleanup-configuration
18846 (directory "/var/log/guix/drvs")))
18849 That ensures build logs do not accumulate endlessly.
18851 @defvr {Scheme Variable} log-cleanup-service-type
18852 This is the type of the service to delete old logs. Its value must be a
18853 @code{log-cleanup-configuration} record as described below.
18856 @deftp {Data Type} log-cleanup-configuration
18857 Data type representing the log cleanup configuration
18860 @item @code{directory}
18861 Name of the directory containing log files.
18863 @item @code{expiry} (default: @code{(* 6 30 24 3600)})
18864 Age in seconds after which a file is subject to deletion (six months by
18867 @item @code{schedule} (default: @code{"30 12 01,08,15,22 * *"})
18868 String or gexp denoting the corresponding mcron job schedule
18869 (@pxref{Scheduled Job Execution}).
18873 @cindex logging, anonymization
18874 @subheading Anonip Service
18876 Anonip is a privacy filter that removes IP address from web server logs.
18877 This service creates a FIFO and filters any written lines with anonip
18878 before writing the filtered log to a target file.
18880 The following example sets up the FIFO
18881 @file{/var/run/anonip/https.access.log} and writes the filtered log file
18882 @file{/var/log/anonip/https.access.log}.
18885 (service anonip-service-type
18886 (anonip-configuration
18887 (input "/var/run/anonip/https.access.log")
18888 (output "/var/log/anonip/https.access.log")))
18891 Configure your web server to write its logs to the FIFO at
18892 @file{/var/run/anonip/https.access.log} and collect the anonymized log
18893 file at @file{/var/web-logs/https.access.log}.
18895 @deftp {Data Type} anonip-configuration
18896 This data type represents the configuration of anonip.
18897 It has the following parameters:
18900 @item @code{anonip} (default: @code{anonip})
18901 The anonip package to use.
18904 The file name of the input log file to process. The service creates a
18905 FIFO of this name. The web server should write its logs to this FIFO.
18907 @item @code{output}
18908 The file name of the processed log file.
18911 The following optional settings may be provided:
18914 @item @code{skip-private?}
18915 When @code{#true} do not mask addresses in private ranges.
18917 @item @code{column}
18918 A 1-based indexed column number. Assume IP address is in the specified
18919 column (default is 1).
18921 @item @code{replacement}
18922 Replacement string in case address parsing fails, e.g. @code{"0.0.0.0"}.
18924 @item @code{ipv4mask}
18925 Number of bits to mask in IPv4 addresses.
18927 @item @code{ipv6mask}
18928 Number of bits to mask in IPv6 addresses.
18930 @item @code{increment}
18931 Increment the IP address by the given number. By default this is zero.
18933 @item @code{delimiter}
18934 Log delimiter string.
18937 Regular expression for detecting IP addresses. Use this instead of @code{column}.
18942 @node Networking Setup
18943 @subsection Networking Setup
18945 The @code{(gnu services networking)} module provides services to
18946 configure network interfaces and set up networking on your machine.
18947 Those services provide different ways for you to set up your machine: by
18948 declaring a static network configuration, by running a Dynamic Host
18949 Configuration Protocol (DHCP) client, or by running daemons such as
18950 NetworkManager and Connman that automate the whole process,
18951 automatically adapt to connectivity changes, and provide a high-level
18954 On a laptop, NetworkManager and Connman are by far the most convenient
18955 options, which is why the default desktop services include
18956 NetworkManager (@pxref{Desktop Services, @code{%desktop-services}}).
18957 For a server, or for a virtual machine or a container, static network
18958 configuration or a simple DHCP client are often more appropriate.
18960 This section describes the various network setup services available,
18961 starting with static network configuration.
18963 @defvr {Scheme Variable} static-networking-service-type
18964 This is the type for statically-configured network interfaces. Its
18965 value must be a list of @code{static-networking} records. Each of them
18966 declares a set of @dfn{addresses}, @dfn{routes}, and @dfn{links}, as
18969 @cindex network interface controller (NIC)
18970 @cindex NIC, networking interface controller
18971 Here is the simplest configuration, with only one network interface
18972 controller (NIC) and only IPv4 connectivity:
18975 ;; Static networking for one NIC, IPv4-only.
18976 (service static-networking-service-type
18977 (list (static-networking
18979 (list (network-address
18981 (value "10.0.2.15/24"))))
18983 (list (network-route
18984 (destination "default")
18985 (gateway "10.0.2.2"))))
18986 (name-servers '("10.0.2.3")))))
18989 The snippet above can be added to the @code{services} field of your
18990 operating system configuration (@pxref{Using the Configuration System}).
18991 It will configure your machine to have 10.0.2.15 as its IP address, with
18992 a 24-bit netmask for the local network---meaning that any 10.0.2.@var{x}
18993 address is on the local area network (LAN). Traffic to addresses
18994 outside the local network is routed @i{via} 10.0.2.2. Host names are
18995 resolved by sending domain name system (DNS) queries to 10.0.2.3.
18998 @deftp {Data Type} static-networking
18999 This is the data type representing a static network configuration.
19001 As an example, here is how you would declare the configuration of a
19002 machine with a single network interface controller (NIC) available as
19003 @code{eno1}, and with one IPv4 and one IPv6 address:
19006 ;; Network configuration for one NIC, IPv4 + IPv6.
19008 (addresses (list (network-address
19010 (value "10.0.2.15/24"))
19013 (value "2001:123:4567:101::1/64"))))
19014 (routes (list (network-route
19015 (destination "default")
19016 (gateway "10.0.2.2"))
19018 (destination "default")
19019 (gateway "2020:321:4567:42::1"))))
19020 (name-servers '("10.0.2.3")))
19023 If you are familiar with the @command{ip} command of the
19024 @uref{https://wiki.linuxfoundation.org/networking/iproute2,
19025 @code{iproute2} package} found on Linux-based systems, the declaration
19026 above is equivalent to typing:
19029 ip address add 10.0.2.15/24 dev eno1
19030 ip address add 2001:123:4567:101::1/64 dev eno1
19031 ip route add default via inet 10.0.2.2
19032 ip route add default via inet6 2020:321:4567:42::1
19035 Run @command{man 8 ip} for more info. Venerable GNU/Linux users will
19036 certainly know how to do it with @command{ifconfig} and @command{route},
19037 but we'll spare you that.
19039 The available fields of this data type are as follows:
19042 @item @code{addresses}
19043 @itemx @code{links} (default: @code{'()})
19044 @itemx @code{routes} (default: @code{'()})
19045 The list of @code{network-address}, @code{network-link}, and
19046 @code{network-route} records for this network (see below).
19048 @item @code{name-servers} (default: @code{'()})
19049 The list of IP addresses (strings) of domain name servers. These IP
19050 addresses go to @file{/etc/resolv.conf}.
19052 @item @code{provision} (default: @code{'(networking)})
19053 If true, this should be a list of symbols for the Shepherd service
19054 corresponding to this network configuration.
19056 @item @code{requirement} (default @code{'()})
19057 The list of Shepherd services depended on.
19061 @deftp {Data Type} network-address
19062 This is the data type representing the IP address of a network
19067 The name of the network interface for this address---e.g.,
19071 The actual IP address and network mask, in
19072 @uref{https://en.wikipedia.org/wiki/CIDR#CIDR_notation, @acronym{CIDR,
19073 Classless Inter-Domain Routing} notation}, as a string.
19075 For example, @code{"10.0.2.15/24"} denotes IPv4 address 10.0.2.15 on a
19076 24-bit sub-network---all 10.0.2.@var{x} addresses are on the same local
19080 Whether @code{value} denotes an IPv6 address. By default this is
19081 automatically determined.
19085 @deftp {Data Type} network-route
19086 This is the data type representing a network route.
19089 @item @code{destination}
19090 The route destination (a string), either an IP address or
19091 @code{"default"} to denote the default route.
19093 @item @code{source} (default: @code{#f})
19096 @item @code{device} (default: @code{#f})
19097 The device used for this route---e.g., @code{"eno2"}.
19099 @item @code{ipv6?} (default: auto)
19100 Whether this is an IPv6 route. By default this is automatically
19101 determined based on @code{destination} or @code{gateway}.
19103 @item @code{gateway} (default: @code{#f})
19104 IP address (a string) through which traffic is routed.
19108 @deftp {Data Type} network-link
19109 Data type for a network link (@pxref{Link,,, guile-netlink,
19110 Guile-Netlink Manual}).
19114 The name of the link---e.g., @code{"v0p0"}.
19117 A symbol denoting the type of the link---e.g., @code{'veth}.
19120 List of arguments for this type of link.
19124 @cindex loopback device
19125 @defvr {Scheme Variable} %loopback-static-networking
19126 This is the @code{static-networking} record representing the ``loopback
19127 device'', @code{lo}, for IP addresses 127.0.0.1 and ::1, and providing
19128 the @code{loopback} Shepherd service.
19131 @cindex networking, with QEMU
19132 @cindex QEMU, networking
19133 @defvr {Scheme Variable} %qemu-static-networking
19134 This is the @code{static-networking} record representing network setup
19135 when using QEMU's user-mode network stack on @code{eth0} (@pxref{Using
19136 the user mode network stack,,, QEMU, QEMU Documentation}).
19139 @cindex DHCP, networking service
19140 @defvr {Scheme Variable} dhcp-client-service-type
19141 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
19142 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
19143 is the DHCP client package to use, @code{isc-dhcp} by default.
19146 @cindex NetworkManager
19148 @defvr {Scheme Variable} network-manager-service-type
19149 This is the service type for the
19150 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
19151 service. The value for this service type is a
19152 @code{network-manager-configuration} record.
19154 This service is part of @code{%desktop-services} (@pxref{Desktop
19158 @deftp {Data Type} network-manager-configuration
19159 Data type representing the configuration of NetworkManager.
19162 @item @code{network-manager} (default: @code{network-manager})
19163 The NetworkManager package to use.
19165 @item @code{dns} (default: @code{"default"})
19166 Processing mode for DNS, which affects how NetworkManager uses the
19167 @code{resolv.conf} configuration file.
19171 NetworkManager will update @code{resolv.conf} to reflect the nameservers
19172 provided by currently active connections.
19175 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
19176 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
19177 then update @code{resolv.conf} to point to the local nameserver.
19179 With this setting, you can share your network connection. For example when
19180 you want to share your network connection to another laptop @i{via} an
19181 Ethernet cable, you can open @command{nm-connection-editor} and configure the
19182 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
19183 and reestablish the connection (or reboot).
19185 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
19186 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
19187 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
19188 browser on your host system, or connect to the VM @i{via} SSH
19189 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
19190 host-to-guest connection, run this command once:
19193 nmcli connection add type tun \
19194 connection.interface-name tap0 \
19195 tun.mode tap tun.owner $(id -u) \
19196 ipv4.method shared \
19197 ipv4.addresses 172.28.112.1/24
19200 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
19201 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
19202 @command{qemu-system-...}.
19205 NetworkManager will not modify @code{resolv.conf}.
19208 @item @code{vpn-plugins} (default: @code{'()})
19209 This is the list of available plugins for virtual private networks
19210 (VPNs). An example of this is the @code{network-manager-openvpn}
19211 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
19217 @deffn {Scheme Variable} connman-service-type
19218 This is the service type to run @url{https://01.org/connman,Connman},
19219 a network connection manager.
19221 Its value must be an
19222 @code{connman-configuration} record as in this example:
19225 (service connman-service-type
19226 (connman-configuration
19227 (disable-vpn? #t)))
19230 See below for details about @code{connman-configuration}.
19233 @deftp {Data Type} connman-configuration
19234 Data Type representing the configuration of connman.
19237 @item @code{connman} (default: @var{connman})
19238 The connman package to use.
19240 @item @code{disable-vpn?} (default: @code{#f})
19241 When true, disable connman's vpn plugin.
19245 @cindex WPA Supplicant
19246 @defvr {Scheme Variable} wpa-supplicant-service-type
19247 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
19248 supplicant}, an authentication daemon required to authenticate against
19249 encrypted WiFi or ethernet networks.
19252 @deftp {Data Type} wpa-supplicant-configuration
19253 Data type representing the configuration of WPA Supplicant.
19255 It takes the following parameters:
19258 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
19259 The WPA Supplicant package to use.
19261 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
19262 List of services that should be started before WPA Supplicant starts.
19264 @item @code{dbus?} (default: @code{#t})
19265 Whether to listen for requests on D-Bus.
19267 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
19268 Where to store the PID file.
19270 @item @code{interface} (default: @code{#f})
19271 If this is set, it must specify the name of a network interface that
19272 WPA supplicant will control.
19274 @item @code{config-file} (default: @code{#f})
19275 Optional configuration file to use.
19277 @item @code{extra-options} (default: @code{'()})
19278 List of additional command-line arguments to pass to the daemon.
19282 @cindex ModemManager
19283 Some networking devices such as modems require special care, and this is
19284 what the services below focus on.
19286 @defvr {Scheme Variable} modem-manager-service-type
19287 This is the service type for the
19288 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
19289 service. The value for this service type is a
19290 @code{modem-manager-configuration} record.
19292 This service is part of @code{%desktop-services} (@pxref{Desktop
19296 @deftp {Data Type} modem-manager-configuration
19297 Data type representing the configuration of ModemManager.
19300 @item @code{modem-manager} (default: @code{modem-manager})
19301 The ModemManager package to use.
19306 @cindex USB_ModeSwitch
19307 @cindex Modeswitching
19309 @defvr {Scheme Variable} usb-modeswitch-service-type
19310 This is the service type for the
19311 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
19312 service. The value for this service type is
19313 a @code{usb-modeswitch-configuration} record.
19315 When plugged in, some USB modems (and other USB devices) initially present
19316 themselves as a read-only storage medium and not as a modem. They need to be
19317 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
19318 installs udev rules to automatically modeswitch these devices when they are
19321 This service is part of @code{%desktop-services} (@pxref{Desktop
19325 @deftp {Data Type} usb-modeswitch-configuration
19326 Data type representing the configuration of USB_ModeSwitch.
19329 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
19330 The USB_ModeSwitch package providing the binaries for modeswitching.
19332 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
19333 The package providing the device data and udev rules file used by
19336 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
19337 Which config file to use for the USB_ModeSwitch dispatcher. By default the
19338 config file shipped with USB_ModeSwitch is used which disables logging to
19339 @file{/var/log} among other default settings. If set to @code{#f}, no config
19346 @node Networking Services
19347 @subsection Networking Services
19349 The @code{(gnu services networking)} module discussed in the previous
19350 section provides services for more advanced setups: providing a DHCP
19351 service for others to use, filtering packets with iptables or nftables,
19352 running a WiFi access point with @command{hostapd}, running the
19353 @command{inetd} ``superdaemon'', and more. This section describes
19356 @deffn {Scheme Procedure} dhcpd-service-type
19357 This type defines a service that runs a DHCP daemon. To create a
19358 service of this type, you must supply a @code{<dhcpd-configuration>}.
19362 (service dhcpd-service-type
19363 (dhcpd-configuration
19364 (config-file (local-file "my-dhcpd.conf"))
19365 (interfaces '("enp0s25"))))
19369 @deftp {Data Type} dhcpd-configuration
19371 @item @code{package} (default: @code{isc-dhcp})
19372 The package that provides the DHCP daemon. This package is expected to
19373 provide the daemon at @file{sbin/dhcpd} relative to its output
19374 directory. The default package is the
19375 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
19376 @item @code{config-file} (default: @code{#f})
19377 The configuration file to use. This is required. It will be passed to
19378 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
19379 object (@pxref{G-Expressions, file-like objects}). See @code{man
19380 dhcpd.conf} for details on the configuration file syntax.
19381 @item @code{version} (default: @code{"4"})
19382 The DHCP version to use. The ISC DHCP server supports the values ``4'',
19383 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
19384 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
19386 @item @code{run-directory} (default: @code{"/run/dhcpd"})
19387 The run directory to use. At service activation time, this directory
19388 will be created if it does not exist.
19389 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
19390 The PID file to use. This corresponds to the @code{-pf} option of
19391 @code{dhcpd}. See @code{man dhcpd} for details.
19392 @item @code{interfaces} (default: @code{'()})
19393 The names of the network interfaces on which dhcpd should listen for
19394 broadcasts. If this list is not empty, then its elements (which must be
19395 strings) will be appended to the @code{dhcpd} invocation when starting
19396 the daemon. It may not be necessary to explicitly specify any
19397 interfaces here; see @code{man dhcpd} for details.
19401 @cindex hostapd service, for Wi-Fi access points
19402 @cindex Wi-Fi access points, hostapd service
19403 @defvr {Scheme Variable} hostapd-service-type
19404 This is the service type to run the @uref{https://w1.fi/hostapd/,
19405 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
19406 authentication servers. Its associated value must be a
19407 @code{hostapd-configuration} as shown below:
19410 ;; Use wlan1 to run the access point for "My Network".
19411 (service hostapd-service-type
19412 (hostapd-configuration
19413 (interface "wlan1")
19414 (ssid "My Network")
19419 @deftp {Data Type} hostapd-configuration
19420 This data type represents the configuration of the hostapd service, with
19421 the following fields:
19424 @item @code{package} (default: @code{hostapd})
19425 The hostapd package to use.
19427 @item @code{interface} (default: @code{"wlan0"})
19428 The network interface to run the WiFi access point.
19431 The SSID (@dfn{service set identifier}), a string that identifies this
19434 @item @code{broadcast-ssid?} (default: @code{#t})
19435 Whether to broadcast this SSID.
19437 @item @code{channel} (default: @code{1})
19438 The WiFi channel to use.
19440 @item @code{driver} (default: @code{"nl80211"})
19441 The driver interface type. @code{"nl80211"} is used with all Linux
19442 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
19443 RADIUS server that does # not control any wireless/wired driver.
19445 @item @code{extra-settings} (default: @code{""})
19446 Extra settings to append as-is to the hostapd configuration file. See
19447 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
19448 configuration file reference.
19452 @defvr {Scheme Variable} simulated-wifi-service-type
19453 This is the type of a service to simulate WiFi networking, which can be
19454 useful in virtual machines for testing purposes. The service loads the
19456 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
19457 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
19458 network that can be seen on @code{wlan0}, by default.
19460 The service's value is a @code{hostapd-configuration} record.
19465 @defvr {Scheme Variable} iptables-service-type
19466 This is the service type to set up an iptables configuration. iptables is a
19467 packet filtering framework supported by the Linux kernel. This service
19468 supports configuring iptables for both IPv4 and IPv6. A simple example
19469 configuration rejecting all incoming connections except those to the ssh port
19473 (service iptables-service-type
19474 (iptables-configuration
19475 (ipv4-rules (plain-file "iptables.rules" "*filter
19479 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19480 -A INPUT -p tcp --dport 22 -j ACCEPT
19481 -A INPUT -j REJECT --reject-with icmp-port-unreachable
19484 (ipv6-rules (plain-file "ip6tables.rules" "*filter
19488 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19489 -A INPUT -p tcp --dport 22 -j ACCEPT
19490 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
19496 @deftp {Data Type} iptables-configuration
19497 The data type representing the configuration of iptables.
19500 @item @code{iptables} (default: @code{iptables})
19501 The iptables package that provides @code{iptables-restore} and
19502 @code{ip6tables-restore}.
19503 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
19504 The iptables rules to use. It will be passed to @code{iptables-restore}.
19505 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19507 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
19508 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
19509 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19515 @defvr {Scheme Variable} nftables-service-type
19516 This is the service type to set up a nftables configuration. nftables is a
19517 netfilter project that aims to replace the existing iptables, ip6tables,
19518 arptables and ebtables framework. It provides a new packet filtering
19519 framework, a new user-space utility @command{nft}, and a compatibility layer
19520 for iptables. This service comes with a default ruleset
19521 @code{%default-nftables-ruleset} that rejecting all incoming connections
19522 except those to the ssh port 22. To use it, simply write:
19525 (service nftables-service-type)
19529 @deftp {Data Type} nftables-configuration
19530 The data type representing the configuration of nftables.
19533 @item @code{package} (default: @code{nftables})
19534 The nftables package that provides @command{nft}.
19535 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
19536 The nftables ruleset to use. This may be any ``file-like'' object
19537 (@pxref{G-Expressions, file-like objects}).
19541 @cindex NTP (Network Time Protocol), service
19542 @cindex ntpd, service for the Network Time Protocol daemon
19543 @cindex real time clock
19544 @defvr {Scheme Variable} ntp-service-type
19545 This is the type of the service running the @uref{https://www.ntp.org,
19546 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
19547 system clock synchronized with that of the specified NTP servers.
19549 The value of this service is an @code{ntpd-configuration} object, as described
19553 @deftp {Data Type} ntp-configuration
19554 This is the data type for the NTP service configuration.
19557 @item @code{servers} (default: @code{%ntp-servers})
19558 This is the list of servers (@code{<ntp-server>} records) with which
19559 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
19562 @item @code{allow-large-adjustment?} (default: @code{#t})
19563 This determines whether @command{ntpd} is allowed to make an initial
19564 adjustment of more than 1,000 seconds.
19566 @item @code{ntp} (default: @code{ntp})
19567 The NTP package to use.
19571 @defvr {Scheme Variable} %ntp-servers
19572 List of host names used as the default NTP servers. These are servers of the
19573 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
19576 @deftp {Data Type} ntp-server
19577 The data type representing the configuration of a NTP server.
19580 @item @code{type} (default: @code{'server})
19581 The type of the NTP server, given as a symbol. One of @code{'pool},
19582 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
19584 @item @code{address}
19585 The address of the server, as a string.
19587 @item @code{options}
19588 NTPD options to use with that specific server, given as a list of option names
19589 and/or of option names and values tuples. The following example define a server
19590 to use with the options @option{iburst} and @option{prefer}, as well as
19591 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
19596 (address "some.ntp.server.org")
19597 (options `(iburst (version 3) (maxpoll 16) prefer))))
19603 @deffn {Scheme Procedure} openntpd-service-type
19604 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
19605 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
19606 clock synchronized with that of the given servers.
19610 openntpd-service-type
19611 (openntpd-configuration
19612 (listen-on '("127.0.0.1" "::1"))
19613 (sensor '("udcf0 correction 70000"))
19614 (constraint-from '("www.gnu.org"))
19615 (constraints-from '("https://www.google.com/"))))
19620 @defvr {Scheme Variable} %openntpd-servers
19621 This variable is a list of the server addresses defined in
19622 @code{%ntp-servers}.
19625 @deftp {Data Type} openntpd-configuration
19627 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
19628 The openntpd executable to use.
19629 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
19630 A list of local IP addresses or hostnames the ntpd daemon should listen on.
19631 @item @code{query-from} (default: @code{'()})
19632 A list of local IP address the ntpd daemon should use for outgoing queries.
19633 @item @code{sensor} (default: @code{'()})
19634 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
19635 will listen to each sensor that actually exists and ignore non-existent ones.
19636 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
19638 @item @code{server} (default: @code{'()})
19639 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
19640 @item @code{servers} (default: @code{%openntp-servers})
19641 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
19642 @item @code{constraint-from} (default: @code{'()})
19643 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
19644 This time information is not used for precision but acts as an authenticated
19645 constraint, thereby reducing the impact of unauthenticated NTP
19646 man-in-the-middle attacks.
19647 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
19649 @item @code{constraints-from} (default: @code{'()})
19650 As with constraint from, specify a list of URLs, IP addresses or hostnames of
19651 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
19652 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
19657 @deffn {Scheme variable} inetd-service-type
19658 This service runs the @command{inetd} (@pxref{inetd invocation,,,
19659 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
19660 connections on internet sockets, and lazily starts the specified server
19661 program when a connection is made on one of these sockets.
19663 The value of this service is an @code{inetd-configuration} object. The
19664 following example configures the @command{inetd} daemon to provide the
19665 built-in @command{echo} service, as well as an smtp service which
19666 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
19667 gateway @code{hostname}:
19672 (inetd-configuration
19676 (socket-type 'stream)
19683 (socket-type 'stream)
19687 (program (file-append openssh "/bin/ssh"))
19689 '("ssh" "-qT" "-i" "/path/to/ssh_key"
19690 "-W" "smtp-server:25" "user@@hostname")))))))
19693 See below for more details about @code{inetd-configuration}.
19696 @deftp {Data Type} inetd-configuration
19697 Data type representing the configuration of @command{inetd}.
19700 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
19701 The @command{inetd} executable to use.
19703 @item @code{entries} (default: @code{'()})
19704 A list of @command{inetd} service entries. Each entry should be created
19705 by the @code{inetd-entry} constructor.
19709 @deftp {Data Type} inetd-entry
19710 Data type representing an entry in the @command{inetd} configuration.
19711 Each entry corresponds to a socket where @command{inetd} will listen for
19715 @item @code{node} (default: @code{#f})
19716 Optional string, a comma-separated list of local addresses
19717 @command{inetd} should use when listening for this service.
19718 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
19719 description of all options.
19721 A string, the name must correspond to an entry in @code{/etc/services}.
19722 @item @code{socket-type}
19723 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
19725 @item @code{protocol}
19726 A string, must correspond to an entry in @code{/etc/protocols}.
19727 @item @code{wait?} (default: @code{#t})
19728 Whether @command{inetd} should wait for the server to exit before
19729 listening to new service requests.
19731 A string containing the user (and, optionally, group) name of the user
19732 as whom the server should run. The group name can be specified in a
19733 suffix, separated by a colon or period, i.e.@: @code{"user"},
19734 @code{"user:group"} or @code{"user.group"}.
19735 @item @code{program} (default: @code{"internal"})
19736 The server program which will serve the requests, or @code{"internal"}
19737 if @command{inetd} should use a built-in service.
19738 @item @code{arguments} (default: @code{'()})
19739 A list strings or file-like objects, which are the server program's
19740 arguments, starting with the zeroth argument, i.e.@: the name of the
19741 program itself. For @command{inetd}'s internal services, this entry
19742 must be @code{'()} or @code{'("internal")}.
19745 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
19746 detailed discussion of each configuration field.
19749 @cindex opendht, distributed hash table network service
19750 @cindex dhtproxy, for use with jami
19751 @defvr {Scheme Variable} opendht-service-type
19752 This is the type of the service running a @uref{https://opendht.net,
19753 OpenDHT} node, @command{dhtnode}. The daemon can be used to host your
19754 own proxy service to the distributed hash table (DHT), for example to
19755 connect to with Jami, among other applications.
19757 @quotation Important
19758 When using the OpenDHT proxy server, the IP addresses it ``sees'' from
19759 the clients should be addresses reachable from other peers. In practice
19760 this means that a publicly reachable address is best suited for a proxy
19761 server, outside of your private network. For example, hosting the proxy
19762 server on a IPv4 private local network and exposing it via port
19763 forwarding could work for external peers, but peers local to the proxy
19764 would have their private addresses shared with the external peers,
19765 leading to connectivity problems.
19768 The value of this service is a @code{opendht-configuration} object, as
19772 @c The fields documentation has been auto-generated using the
19773 @c configuration->documentation procedure from
19774 @c (gnu services configuration).
19775 @deftp {Data Type} opendht-configuration
19776 Available @code{opendht-configuration} fields are:
19779 @item @code{opendht} (default: @code{opendht}) (type: file-like)
19780 The @code{opendht} package to use.
19782 @item @code{peer-discovery?} (default: @code{#f}) (type: boolean)
19783 Whether to enable the multicast local peer discovery mechanism.
19785 @item @code{enable-logging?} (default: @code{#f}) (type: boolean)
19786 Whether to enable logging messages to syslog. It is disabled by default
19787 as it is rather verbose.
19789 @item @code{debug?} (default: @code{#f}) (type: boolean)
19790 Whether to enable debug-level logging messages. This has no effect if
19791 logging is disabled.
19793 @item @code{bootstrap-host} (default: @code{"bootstrap.jami.net:4222"}) (type: maybe-string)
19794 The node host name that is used to make the first connection to the
19795 network. A specific port value can be provided by appending the
19796 @code{:PORT} suffix. By default, it uses the Jami bootstrap nodes, but
19797 any host can be specified here. It's also possible to disable
19798 bootstrapping by explicitly setting this field to the
19799 @code{'unset} value.
19801 @item @code{port} (default: @code{4222}) (type: maybe-number)
19802 The UDP port to bind to. When left unspecified, an available port is
19803 automatically selected.
19805 @item @code{proxy-server-port} (type: maybe-number)
19806 Spawn a proxy server listening on the specified port.
19808 @item @code{proxy-server-port-tls} (type: maybe-number)
19809 Spawn a proxy server listening to TLS connections on the specified port.
19815 @defvr {Scheme Variable} tor-service-type
19816 This is the type for a service that runs the @uref{https://torproject.org,
19817 Tor} anonymous networking daemon. The service is configured using a
19818 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
19819 @code{tor} unprivileged user, which is a member of the @code{tor} group.
19823 @deftp {Data Type} tor-configuration
19825 @item @code{tor} (default: @code{tor})
19826 The package that provides the Tor daemon. This package is expected to provide
19827 the daemon at @file{bin/tor} relative to its output directory. The default
19828 package is the @uref{https://www.torproject.org, Tor Project's}
19831 @item @code{config-file} (default: @code{(plain-file "empty" "")})
19832 The configuration file to use. It will be appended to a default configuration
19833 file, and the final configuration file will be passed to @code{tor} via its
19834 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
19835 file-like objects}). See @code{man tor} for details on the configuration file
19838 @item @code{hidden-services} (default: @code{'()})
19839 The list of @code{<hidden-service>} records to use. For any hidden service
19840 you include in this list, appropriate configuration to enable the hidden
19841 service will be automatically added to the default configuration file. You
19842 may conveniently create @code{<hidden-service>} records using the
19843 @code{tor-hidden-service} procedure described below.
19845 @item @code{socks-socket-type} (default: @code{'tcp})
19846 The default socket type that Tor should use for its SOCKS socket. This must
19847 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
19848 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
19849 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
19850 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
19853 If you want to customize the SOCKS socket in more detail, leave
19854 @code{socks-socket-type} at its default value of @code{'tcp} and use
19855 @code{config-file} to override the default by providing your own
19856 @code{SocksPort} option.
19858 @item @code{control-socket?} (default: @code{#f})
19859 Whether or not to provide a ``control socket'' by which Tor can be
19860 controlled to, for instance, dynamically instantiate tor onion services.
19861 If @code{#t}, Tor will listen for control commands on the UNIX domain socket
19862 @file{/var/run/tor/control-sock}, which will be made writable by members of the
19868 @cindex hidden service
19869 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
19870 Define a new Tor @dfn{hidden service} called @var{name} and implementing
19871 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
19874 '((22 "127.0.0.1:22")
19875 (80 "127.0.0.1:8080"))
19878 In this example, port 22 of the hidden service is mapped to local port 22, and
19879 port 80 is mapped to local port 8080.
19881 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
19882 the @file{hostname} file contains the @code{.onion} host name for the hidden
19885 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
19886 project's documentation} for more information.
19889 The @code{(gnu services rsync)} module provides the following services:
19891 You might want an rsync daemon if you have files that you want available
19892 so anyone (or just yourself) can download existing files or upload new
19895 @deffn {Scheme Variable} rsync-service-type
19896 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
19897 The value for this service type is a
19898 @command{rsync-configuration} record as in this example:
19901 ;; Export two directories over rsync. By default rsync listens on
19902 ;; all the network interfaces.
19903 (service rsync-service-type
19904 (rsync-configuration
19905 (modules (list (rsync-module
19907 (file-name "/srv/zik")
19911 (file-name "/home/charlie/movies"))))))
19914 See below for details about @code{rsync-configuration}.
19917 @deftp {Data Type} rsync-configuration
19918 Data type representing the configuration for @code{rsync-service}.
19921 @item @code{package} (default: @var{rsync})
19922 @code{rsync} package to use.
19924 @item @code{address} (default: @code{#f})
19925 IP address on which @command{rsync} listens for incoming connections.
19926 If unspecified, it defaults to listening on all available addresses.
19928 @item @code{port-number} (default: @code{873})
19929 TCP port on which @command{rsync} listens for incoming connections. If port
19930 is less than @code{1024} @command{rsync} needs to be started as the
19931 @code{root} user and group.
19933 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
19934 Name of the file where @command{rsync} writes its PID.
19936 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
19937 Name of the file where @command{rsync} writes its lock file.
19939 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
19940 Name of the file where @command{rsync} writes its log file.
19942 @item @code{user} (default: @code{"root"})
19943 Owner of the @code{rsync} process.
19945 @item @code{group} (default: @code{"root"})
19946 Group of the @code{rsync} process.
19948 @item @code{uid} (default: @code{"rsyncd"})
19949 User name or user ID that file transfers to and from that module should take
19950 place as when the daemon was run as @code{root}.
19952 @item @code{gid} (default: @code{"rsyncd"})
19953 Group name or group ID that will be used when accessing the module.
19955 @item @code{modules} (default: @code{%default-modules})
19956 List of ``modules''---i.e., directories exported over rsync. Each
19957 element must be a @code{rsync-module} record, as described below.
19961 @deftp {Data Type} rsync-module
19962 This is the data type for rsync ``modules''. A module is a directory
19963 exported over the rsync protocol. The available fields are as follows:
19967 The module name. This is the name that shows up in URLs. For example,
19968 if the module is called @code{music}, the corresponding URL will be
19969 @code{rsync://host.example.org/music}.
19971 @item @code{file-name}
19972 Name of the directory being exported.
19974 @item @code{comment} (default: @code{""})
19975 Comment associated with the module. Client user interfaces may display
19976 it when they obtain the list of available modules.
19978 @item @code{read-only?} (default: @code{#t})
19979 Whether or not client will be able to upload files. If this is false,
19980 the uploads will be authorized if permissions on the daemon side permit
19983 @item @code{chroot?} (default: @code{#t})
19984 When this is true, the rsync daemon changes root to the module's
19985 directory before starting file transfers with the client. This improves
19986 security, but requires rsync to run as root.
19988 @item @code{timeout} (default: @code{300})
19989 Idle time in seconds after which the daemon closes a connection with the
19994 The @code{(gnu services syncthing)} module provides the following services:
19997 You might want a syncthing daemon if you have files between two or more
19998 computers and want to sync them in real time, safely protected from
20001 @deffn {Scheme Variable} syncthing-service-type
20002 This is the service type for the @uref{https://syncthing.net/,
20003 syncthing} daemon, The value for this service type is a
20004 @command{syncthing-configuration} record as in this example:
20007 (service syncthing-service-type
20008 (syncthing-configuration (user "alice")))
20011 See below for details about @code{syncthing-configuration}.
20013 @deftp {Data Type} syncthing-configuration
20014 Data type representing the configuration for @code{syncthing-service-type}.
20017 @item @code{syncthing} (default: @var{syncthing})
20018 @code{syncthing} package to use.
20020 @item @code{arguments} (default: @var{'()})
20021 List of command-line arguments passing to @code{syncthing} binary.
20023 @item @code{logflags} (default: @var{0})
20024 Sum of logging flags, see
20025 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
20027 @item @code{user} (default: @var{#f})
20028 The user as which the Syncthing service is to be run.
20029 This assumes that the specified user exists.
20031 @item @code{group} (default: @var{"users"})
20032 The group as which the Syncthing service is to be run.
20033 This assumes that the specified group exists.
20035 @item @code{home} (default: @var{#f})
20036 Common configuration and data directory. The default configuration
20037 directory is @file{$HOME} of the specified Syncthing @code{user}.
20043 Furthermore, @code{(gnu services ssh)} provides the following services.
20047 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
20048 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
20049 [#:allow-empty-passwords? #f] [#:root-login? #f] @
20050 [#:syslog-output? #t] [#:x11-forwarding? #t] @
20051 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
20052 [#:public-key-authentication? #t] [#:initialize? #t]
20053 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
20054 @var{host-key} must designate a file containing the host key, and readable
20057 When @var{daemonic?} is true, @command{lshd} will detach from the
20058 controlling terminal and log its output to syslogd, unless one sets
20059 @var{syslog-output?} to false. Obviously, it also makes lsh-service
20060 depend on existence of syslogd service. When @var{pid-file?} is true,
20061 @command{lshd} writes its PID to the file called @var{pid-file}.
20063 When @var{initialize?} is true, automatically create the seed and host key
20064 upon service activation if they do not exist yet. This may take long and
20065 require interaction.
20067 When @var{initialize?} is false, it is up to the user to initialize the
20068 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
20069 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
20070 basics,,, lsh, LSH Manual}).
20072 When @var{interfaces} is empty, lshd listens for connections on all the
20073 network interfaces; otherwise, @var{interfaces} must be a list of host names
20076 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
20077 passwords, and @var{root-login?} specifies whether to accept log-ins as
20080 The other options should be self-descriptive.
20085 @deffn {Scheme Variable} openssh-service-type
20086 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
20087 shell daemon, @command{sshd}. Its value must be an
20088 @code{openssh-configuration} record as in this example:
20091 (service openssh-service-type
20092 (openssh-configuration
20093 (x11-forwarding? #t)
20094 (permit-root-login 'prohibit-password)
20096 `(("alice" ,(local-file "alice.pub"))
20097 ("bob" ,(local-file "bob.pub"))))))
20100 See below for details about @code{openssh-configuration}.
20102 This service can be extended with extra authorized keys, as in this
20106 (service-extension openssh-service-type
20107 (const `(("charlie"
20108 ,(local-file "charlie.pub")))))
20112 @deftp {Data Type} openssh-configuration
20113 This is the configuration record for OpenSSH's @command{sshd}.
20116 @item @code{openssh} (default @var{openssh})
20117 The OpenSSH package to use.
20119 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
20120 Name of the file where @command{sshd} writes its PID.
20122 @item @code{port-number} (default: @code{22})
20123 TCP port on which @command{sshd} listens for incoming connections.
20125 @item @code{max-connections} (default: @code{200})
20126 Hard limit on the maximum number of simultaneous client connections,
20127 enforced by the inetd-style Shepherd service (@pxref{Service De- and
20128 Constructors, @code{make-inetd-constructor},, shepherd, The GNU Shepherd
20131 @item @code{permit-root-login} (default: @code{#f})
20132 This field determines whether and when to allow logins as root. If
20133 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
20134 If it's the symbol @code{'prohibit-password}, then root logins are
20135 permitted but not with password-based authentication.
20137 @item @code{allow-empty-passwords?} (default: @code{#f})
20138 When true, users with empty passwords may log in. When false, they may
20141 @item @code{password-authentication?} (default: @code{#t})
20142 When true, users may log in with their password. When false, they have
20143 other authentication methods.
20145 @item @code{public-key-authentication?} (default: @code{#t})
20146 When true, users may log in using public key authentication. When
20147 false, users have to use other authentication method.
20149 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
20150 This is used only by protocol version 2.
20152 @item @code{x11-forwarding?} (default: @code{#f})
20153 When true, forwarding of X11 graphical client connections is
20154 enabled---in other words, @command{ssh} options @option{-X} and
20155 @option{-Y} will work.
20157 @item @code{allow-agent-forwarding?} (default: @code{#t})
20158 Whether to allow agent forwarding.
20160 @item @code{allow-tcp-forwarding?} (default: @code{#t})
20161 Whether to allow TCP forwarding.
20163 @item @code{gateway-ports?} (default: @code{#f})
20164 Whether to allow gateway ports.
20166 @item @code{challenge-response-authentication?} (default: @code{#f})
20167 Specifies whether challenge response authentication is allowed (e.g.@: via
20170 @item @code{use-pam?} (default: @code{#t})
20171 Enables the Pluggable Authentication Module interface. If set to
20172 @code{#t}, this will enable PAM authentication using
20173 @code{challenge-response-authentication?} and
20174 @code{password-authentication?}, in addition to PAM account and session
20175 module processing for all authentication types.
20177 Because PAM challenge response authentication usually serves an
20178 equivalent role to password authentication, you should disable either
20179 @code{challenge-response-authentication?} or
20180 @code{password-authentication?}.
20182 @item @code{print-last-log?} (default: @code{#t})
20183 Specifies whether @command{sshd} should print the date and time of the
20184 last user login when a user logs in interactively.
20186 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
20187 Configures external subsystems (e.g.@: file transfer daemon).
20189 This is a list of two-element lists, each of which containing the
20190 subsystem name and a command (with optional arguments) to execute upon
20193 The command @command{internal-sftp} implements an in-process SFTP
20194 server. Alternatively, one can specify the @command{sftp-server} command:
20196 (service openssh-service-type
20197 (openssh-configuration
20199 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
20202 @item @code{accepted-environment} (default: @code{'()})
20203 List of strings describing which environment variables may be exported.
20205 Each string gets on its own line. See the @code{AcceptEnv} option in
20206 @code{man sshd_config}.
20208 This example allows ssh-clients to export the @env{COLORTERM} variable.
20209 It is set by terminal emulators, which support colors. You can use it in
20210 your shell's resource file to enable colors for the prompt and commands
20211 if this variable is set.
20214 (service openssh-service-type
20215 (openssh-configuration
20216 (accepted-environment '("COLORTERM"))))
20219 @item @code{authorized-keys} (default: @code{'()})
20220 @cindex authorized keys, SSH
20221 @cindex SSH authorized keys
20222 This is the list of authorized keys. Each element of the list is a user
20223 name followed by one or more file-like objects that represent SSH public
20227 (openssh-configuration
20229 `(("rekado" ,(local-file "rekado.pub"))
20230 ("chris" ,(local-file "chris.pub"))
20231 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
20235 registers the specified public keys for user accounts @code{rekado},
20236 @code{chris}, and @code{root}.
20238 Additional authorized keys can be specified @i{via}
20239 @code{service-extension}.
20241 Note that this does @emph{not} interfere with the use of
20242 @file{~/.ssh/authorized_keys}.
20244 @item @code{generate-host-keys?} (default: @code{#t})
20245 Whether to generate host key pairs with @command{ssh-keygen -A} under
20246 @file{/etc/ssh} if there are none.
20248 Generating key pairs takes a few seconds when enough entropy is
20249 available and is only done once. You might want to turn it off for
20250 instance in a virtual machine that does not need it because host keys
20251 are provided in some other way, and where the extra boot time is a
20254 @item @code{log-level} (default: @code{'info})
20255 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
20256 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
20257 page for @file{sshd_config} for the full list of level names.
20259 @item @code{extra-content} (default: @code{""})
20260 This field can be used to append arbitrary text to the configuration file. It
20261 is especially useful for elaborate configurations that cannot be expressed
20262 otherwise. This configuration, for example, would generally disable root
20263 logins, but permit them from one specific IP address:
20266 (openssh-configuration
20268 Match Address 192.168.0.1
20269 PermitRootLogin yes"))
20275 @deffn {Scheme Procedure} dropbear-service [@var{config}]
20276 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
20277 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
20280 For example, to specify a Dropbear service listening on port 1234, add
20281 this call to the operating system's @code{services} field:
20284 (dropbear-service (dropbear-configuration
20285 (port-number 1234)))
20289 @deftp {Data Type} dropbear-configuration
20290 This data type represents the configuration of a Dropbear SSH daemon.
20293 @item @code{dropbear} (default: @var{dropbear})
20294 The Dropbear package to use.
20296 @item @code{port-number} (default: 22)
20297 The TCP port where the daemon waits for incoming connections.
20299 @item @code{syslog-output?} (default: @code{#t})
20300 Whether to enable syslog output.
20302 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
20303 File name of the daemon's PID file.
20305 @item @code{root-login?} (default: @code{#f})
20306 Whether to allow @code{root} logins.
20308 @item @code{allow-empty-passwords?} (default: @code{#f})
20309 Whether to allow empty passwords.
20311 @item @code{password-authentication?} (default: @code{#t})
20312 Whether to enable password-based authentication.
20317 @deffn {Scheme Variable} autossh-service-type
20318 This is the type for the @uref{https://www.harding.motd.ca/autossh,
20319 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
20320 restarting it as necessary should it die or stop passing traffic.
20321 AutoSSH can be run manually from the command-line by passing arguments
20322 to the binary @command{autossh} from the package @code{autossh}, but it
20323 can also be run as a Guix service. This latter use case is documented
20326 AutoSSH can be used to forward local traffic to a remote machine using
20327 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
20330 For example, to specify a service running autossh as the user
20331 @code{pino} and forwarding all local connections to port @code{8081} to
20332 @code{remote:8081} using an SSH tunnel, add this call to the operating
20333 system's @code{services} field:
20336 (service autossh-service-type
20337 (autossh-configuration
20339 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
20343 @deftp {Data Type} autossh-configuration
20344 This data type represents the configuration of an AutoSSH service.
20348 @item @code{user} (default @code{"autossh"})
20349 The user as which the AutoSSH service is to be run.
20350 This assumes that the specified user exists.
20352 @item @code{poll} (default @code{600})
20353 Specifies the connection poll time in seconds.
20355 @item @code{first-poll} (default @code{#f})
20356 Specifies how many seconds AutoSSH waits before the first connection
20357 test. After this first test, polling is resumed at the pace defined in
20358 @code{poll}. When set to @code{#f}, the first poll is not treated
20359 specially and will also use the connection poll specified in
20362 @item @code{gate-time} (default @code{30})
20363 Specifies how many seconds an SSH connection must be active before it is
20364 considered successful.
20366 @item @code{log-level} (default @code{1})
20367 The log level, corresponding to the levels used by syslog---so @code{0}
20368 is the most silent while @code{7} is the chattiest.
20370 @item @code{max-start} (default @code{#f})
20371 The maximum number of times SSH may be (re)started before AutoSSH exits.
20372 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
20374 @item @code{message} (default @code{""})
20375 The message to append to the echo message sent when testing connections.
20377 @item @code{port} (default @code{"0"})
20378 The ports used for monitoring the connection. When set to @code{"0"},
20379 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
20380 a positive integer, ports @var{n} and @var{n}+1 are used for
20381 monitoring the connection, such that port @var{n} is the base
20382 monitoring port and @code{n+1} is the echo port. When set to
20383 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
20384 integers, the ports @var{n} and @var{m} are used for monitoring the
20385 connection, such that port @var{n} is the base monitoring port and
20386 @var{m} is the echo port.
20388 @item @code{ssh-options} (default @code{'()})
20389 The list of command-line arguments to pass to @command{ssh} when it is
20390 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
20391 may cause undefined behaviour.
20397 @deffn {Scheme Variable} webssh-service-type
20398 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
20399 program that runs a web SSH client. WebSSH can be run manually from the
20400 command-line by passing arguments to the binary @command{wssh} from the
20401 package @code{webssh}, but it can also be run as a Guix service. This
20402 latter use case is documented here.
20404 For example, to specify a service running WebSSH on loopback interface
20405 on port @code{8888} with reject policy with a list of allowed to
20406 connection hosts, and NGINX as a reverse-proxy to this service listening
20407 for HTTPS connection, add this call to the operating system's
20408 @code{services} field:
20411 (service webssh-service-type
20412 (webssh-configuration (address "127.0.0.1")
20415 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
20416 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
20418 (service nginx-service-type
20419 (nginx-configuration
20422 (nginx-server-configuration
20423 (inherit %webssh-configuration-nginx)
20424 (server-name '("webssh.example.com"))
20425 (listen '("443 ssl"))
20426 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
20427 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
20429 (cons (nginx-location-configuration
20430 (uri "/.well-known")
20431 (body '("root /var/www;")))
20432 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
20436 @deftp {Data Type} webssh-configuration
20437 Data type representing the configuration for @code{webssh-service}.
20440 @item @code{package} (default: @var{webssh})
20441 @code{webssh} package to use.
20443 @item @code{user-name} (default: @var{"webssh"})
20444 User name or user ID that file transfers to and from that module should take
20447 @item @code{group-name} (default: @var{"webssh"})
20448 Group name or group ID that will be used when accessing the module.
20450 @item @code{address} (default: @var{#f})
20451 IP address on which @command{webssh} listens for incoming connections.
20453 @item @code{port} (default: @var{8888})
20454 TCP port on which @command{webssh} listens for incoming connections.
20456 @item @code{policy} (default: @var{#f})
20457 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
20459 @item @code{known-hosts} (default: @var{'()})
20460 List of hosts which allowed for SSH connection from @command{webssh}.
20462 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
20463 Name of the file where @command{webssh} writes its log file.
20465 @item @code{log-level} (default: @var{#f})
20471 @defvr {Scheme Variable} %facebook-host-aliases
20472 This variable contains a string for use in @file{/etc/hosts}
20473 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
20474 line contains a entry that maps a known server name of the Facebook
20475 on-line service---e.g., @code{www.facebook.com}---to the local
20476 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
20478 This variable is typically used in the @code{hosts-file} field of an
20479 @code{operating-system} declaration (@pxref{operating-system Reference,
20480 @file{/etc/hosts}}):
20483 (use-modules (gnu) (guix))
20486 (host-name "mymachine")
20489 ;; Create a /etc/hosts file with aliases for "localhost"
20490 ;; and "mymachine", as well as for Facebook servers.
20491 (plain-file "hosts"
20492 (string-append (local-host-aliases host-name)
20493 %facebook-host-aliases))))
20496 This mechanism can prevent programs running locally, such as Web
20497 browsers, from accessing Facebook.
20500 The @code{(gnu services avahi)} provides the following definition.
20502 @defvr {Scheme Variable} avahi-service-type
20503 This is the service that runs @command{avahi-daemon}, a system-wide
20504 mDNS/DNS-SD responder that allows for service discovery and
20505 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
20506 Its value must be an @code{avahi-configuration} record---see below.
20508 This service extends the name service cache daemon (nscd) so that it can
20509 resolve @code{.local} host names using
20510 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
20511 Service Switch}, for information on host name resolution.
20513 Additionally, add the @var{avahi} package to the system profile so that
20514 commands such as @command{avahi-browse} are directly usable.
20517 @deftp {Data Type} avahi-configuration
20518 Data type representation the configuration for Avahi.
20522 @item @code{host-name} (default: @code{#f})
20523 If different from @code{#f}, use that as the host name to
20524 publish for this machine; otherwise, use the machine's actual host name.
20526 @item @code{publish?} (default: @code{#t})
20527 When true, allow host names and services to be published (broadcast) over the
20530 @item @code{publish-workstation?} (default: @code{#t})
20531 When true, @command{avahi-daemon} publishes the machine's host name and IP
20532 address via mDNS on the local network. To view the host names published on
20533 your local network, you can run:
20536 avahi-browse _workstation._tcp
20539 @item @code{wide-area?} (default: @code{#f})
20540 When true, DNS-SD over unicast DNS is enabled.
20542 @item @code{ipv4?} (default: @code{#t})
20543 @itemx @code{ipv6?} (default: @code{#t})
20544 These fields determine whether to use IPv4/IPv6 sockets.
20546 @item @code{domains-to-browse} (default: @code{'()})
20547 This is a list of domains to browse.
20551 @deffn {Scheme Variable} openvswitch-service-type
20552 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
20553 service, whose value should be an @code{openvswitch-configuration}
20557 @deftp {Data Type} openvswitch-configuration
20558 Data type representing the configuration of Open vSwitch, a multilayer
20559 virtual switch which is designed to enable massive network automation
20560 through programmatic extension.
20563 @item @code{package} (default: @var{openvswitch})
20564 Package object of the Open vSwitch.
20569 @defvr {Scheme Variable} pagekite-service-type
20570 This is the service type for the @uref{https://pagekite.net, PageKite} service,
20571 a tunneling solution for making localhost servers publicly visible, even from
20572 behind restrictive firewalls or NAT without forwarded ports. The value for
20573 this service type is a @code{pagekite-configuration} record.
20575 Here's an example exposing the local HTTP and SSH daemons:
20578 (service pagekite-service-type
20579 (pagekite-configuration
20580 (kites '("http:@@kitename:localhost:80:@@kitesecret"
20581 "raw/22:@@kitename:localhost:22:@@kitesecret"))
20582 (extra-file "/etc/pagekite.rc")))
20586 @deftp {Data Type} pagekite-configuration
20587 Data type representing the configuration of PageKite.
20590 @item @code{package} (default: @var{pagekite})
20591 Package object of PageKite.
20593 @item @code{kitename} (default: @code{#f})
20594 PageKite name for authenticating to the frontend server.
20596 @item @code{kitesecret} (default: @code{#f})
20597 Shared secret for authenticating to the frontend server. You should probably
20598 put this inside @code{extra-file} instead.
20600 @item @code{frontend} (default: @code{#f})
20601 Connect to the named PageKite frontend server instead of the
20602 @uref{https://pagekite.net,,pagekite.net} service.
20604 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
20605 List of service kites to use. Exposes HTTP on port 80 by default. The format
20606 is @code{proto:kitename:host:port:secret}.
20608 @item @code{extra-file} (default: @code{#f})
20609 Extra configuration file to read, which you are expected to create manually.
20610 Use this to add additional options and manage shared secrets out-of-band.
20615 @defvr {Scheme Variable} yggdrasil-service-type
20616 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
20617 Yggdrasil network}, an early-stage implementation of a fully end-to-end
20618 encrypted IPv6 network.
20621 Yggdrasil provides name-independent routing with cryptographically generated
20622 addresses. Static addressing means you can keep the same address as long as
20623 you want, even if you move to a new location, or generate a new address (by
20624 generating new keys) whenever you want.
20625 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
20628 Pass it a value of @code{yggdrasil-configuration} to connect it to public
20629 peers and/or local peers.
20631 Here is an example using public peers and a static address. The static
20632 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
20633 (the default value for @code{config-file}).
20636 ;; part of the operating-system declaration
20637 (service yggdrasil-service-type
20638 (yggdrasil-configuration
20639 (autoconf? #f) ;; use only the public peers
20642 ;; https://github.com/yggdrasil-network/public-peers
20643 '((peers . #("tcp://1.2.3.4:1337"))))
20644 ;; /etc/yggdrasil-private.conf is the default value for config-file
20648 # sample content for /etc/yggdrasil-private.conf
20650 # Your public key. Your peers may ask you for this to put
20651 # into their AllowedPublicKeys configuration.
20652 PublicKey: 64277...
20654 # Your private key. DO NOT share this with anyone!
20655 PrivateKey: 5c750...
20660 @deftp {Data Type} yggdrasil-configuration
20661 Data type representing the configuration of Yggdrasil.
20664 @item @code{package} (default: @code{yggdrasil})
20665 Package object of Yggdrasil.
20667 @item @code{json-config} (default: @code{'()})
20668 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
20669 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
20670 the Guix store, which is readable to all users. @strong{Do not store your
20671 private keys in it}. See the output of @code{yggdrasil -genconf} for a
20672 quick overview of valid keys and their default values.
20674 @item @code{autoconf?} (default: @code{#f})
20675 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
20676 and peer with IPv6 neighbors.
20678 @item @code{log-level} (default: @code{'info})
20679 How much detail to include in logs. Use @code{'debug} for more detail.
20681 @item @code{log-to} (default: @code{'stdout})
20682 Where to send logs. By default, the service logs standard output to
20683 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
20684 sends output to the running syslog service.
20686 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
20687 What HJSON file to load sensitive data from. This is where private keys
20688 should be stored, which are necessary to specify if you don't want a
20689 randomized address after each restart. Use @code{#f} to disable. Options
20690 defined in this file take precedence over @code{json-config}. Use the output
20691 of @code{yggdrasil -genconf} as a starting point. To configure a static
20692 address, delete everything except these options:
20695 @item @code{EncryptionPublicKey}
20696 @item @code{EncryptionPrivateKey}
20697 @item @code{SigningPublicKey}
20698 @item @code{SigningPrivateKey}
20704 @defvr {Scheme Variable} ipfs-service-type
20705 The service type for connecting to the @uref{https://ipfs.io,IPFS network},
20706 a global, versioned, peer-to-peer file system. Pass it a
20707 @code{ipfs-configuration} to change the ports used for the gateway and API.
20709 Here's an example configuration, using some non-standard ports:
20712 (service ipfs-service-type
20713 (ipfs-configuration
20714 (gateway "/ip4/127.0.0.1/tcp/8880")
20715 (api "/ip4/127.0.0.1/tcp/8881")))
20719 @deftp {Data Type} ipfs-configuration
20720 Data type representing the configuration of IPFS.
20723 @item @code{package} (default: @code{go-ipfs})
20724 Package object of IPFS.
20726 @item @code{gateway} (default: @code{"/ip4/127.0.0.1/tcp/8082"})
20727 Address of the gateway, in ‘multiaddress’ format.
20729 @item @code{api} (default: @code{"/ip4/127.0.0.1/tcp/5001"})
20730 Address of the API endpoint, in ‘multiaddress’ format.
20735 @deffn {Scheme Variable} keepalived-service-type
20736 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
20737 routing software, @command{keepalived}. Its value must be an
20738 @code{keepalived-configuration} record as in this example for master
20742 (service keepalived-service-type
20743 (keepalived-configuration
20744 (config-file (local-file "keepalived-master.conf"))))
20747 where @file{keepalived-master.conf}:
20750 vrrp_instance my-group @{
20753 virtual_router_id 100
20755 unicast_peer @{ 10.0.0.2 @}
20756 virtual_ipaddress @{
20762 and for backup machine:
20765 (service keepalived-service-type
20766 (keepalived-configuration
20767 (config-file (local-file "keepalived-backup.conf"))))
20770 where @file{keepalived-backup.conf}:
20773 vrrp_instance my-group @{
20776 virtual_router_id 100
20778 unicast_peer @{ 10.0.0.3 @}
20779 virtual_ipaddress @{
20786 @node Unattended Upgrades
20787 @subsection Unattended Upgrades
20789 @cindex unattended upgrades
20790 @cindex upgrades, unattended
20791 Guix provides a service to perform @emph{unattended upgrades}:
20792 periodically, the system automatically reconfigures itself from the
20793 latest Guix. Guix System has several properties that make unattended
20798 upgrades are transactional (either the upgrade succeeds or it fails, but
20799 you cannot end up with an ``in-between'' system state);
20801 the upgrade log is kept---you can view it with @command{guix system
20802 list-generations}---and you can roll back to any previous generation,
20803 should the upgraded system fail to behave as intended;
20805 channel code is authenticated so you know you can only run genuine code
20806 (@pxref{Channels});
20808 @command{guix system reconfigure} prevents downgrades, which makes it
20809 immune to @dfn{downgrade attacks}.
20812 To set up unattended upgrades, add an instance of
20813 @code{unattended-upgrade-service-type} like the one below to the list of
20814 your operating system services:
20817 (service unattended-upgrade-service-type)
20820 The defaults above set up weekly upgrades: every Sunday at midnight.
20821 You do not need to provide the operating system configuration file: it
20822 uses @file{/run/current-system/configuration.scm}, which ensures it
20823 always uses your latest configuration---@pxref{provenance-service-type},
20824 for more information about this file.
20826 There are several things that can be configured, in particular the
20827 periodicity and services (daemons) to be restarted upon completion.
20828 When the upgrade is successful, the service takes care of deleting
20829 system generations older that some threshold, as per @command{guix
20830 system delete-generations}. See the reference below for details.
20832 To ensure that upgrades are actually happening, you can run
20833 @command{guix system describe}. To investigate upgrade failures, visit
20834 the unattended upgrade log file (see below).
20836 @defvr {Scheme Variable} unattended-upgrade-service-type
20837 This is the service type for unattended upgrades. It sets up an mcron
20838 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
20839 reconfigure} from the latest version of the specified channels.
20841 Its value must be a @code{unattended-upgrade-configuration} record (see
20845 @deftp {Data Type} unattended-upgrade-configuration
20846 This data type represents the configuration of the unattended upgrade
20847 service. The following fields are available:
20850 @item @code{schedule} (default: @code{"30 01 * * 0"})
20851 This is the schedule of upgrades, expressed as a gexp containing an
20852 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
20853 mcron, GNU@tie{}mcron}).
20855 @item @code{channels} (default: @code{#~%default-channels})
20856 This gexp specifies the channels to use for the upgrade
20857 (@pxref{Channels}). By default, the tip of the official @code{guix}
20860 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
20861 This field specifies the operating system configuration file to use.
20862 The default is to reuse the config file of the current configuration.
20864 There are cases, though, where referring to
20865 @file{/run/current-system/configuration.scm} is not enough, for instance
20866 because that file refers to extra files (SSH public keys, extra
20867 configuration files, etc.) @i{via} @code{local-file} and similar
20868 constructs. For those cases, we recommend something along these lines:
20871 (unattended-upgrade-configuration
20872 (operating-system-file
20873 (file-append (local-file "." "config-dir" #:recursive? #t)
20877 The effect here is to import all of the current directory into the
20878 store, and to refer to @file{config.scm} within that directory.
20879 Therefore, uses of @code{local-file} within @file{config.scm} will work
20880 as expected. @xref{G-Expressions}, for information about
20881 @code{local-file} and @code{file-append}.
20883 @item @code{services-to-restart} (default: @code{'(mcron)})
20884 This field specifies the Shepherd services to restart when the upgrade
20887 Those services are restarted right away upon completion, as with
20888 @command{herd restart}, which ensures that the latest version is
20889 running---remember that by default @command{guix system reconfigure}
20890 only restarts services that are not currently running, which is
20891 conservative: it minimizes disruption but leaves outdated services
20894 Use @command{herd status} to find out candidates for restarting.
20895 @xref{Services}, for general information about services. Common
20896 services to restart would include @code{ntpd} and @code{ssh-daemon}.
20898 By default, the @code{mcron} service is restarted. This ensures that
20899 the latest version of the unattended upgrade job will be used next time.
20901 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
20902 This is the expiration time in seconds for system generations. System
20903 generations older that this amount of time are deleted with
20904 @command{guix system delete-generations} when an upgrade completes.
20907 The unattended upgrade service does not run the garbage collector. You
20908 will probably want to set up your own mcron job to run @command{guix gc}
20912 @item @code{maximum-duration} (default: @code{3600})
20913 Maximum duration in seconds for the upgrade; past that time, the upgrade
20916 This is primarily useful to ensure the upgrade does not end up
20917 rebuilding or re-downloading ``the world''.
20919 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
20920 File where unattended upgrades are logged.
20925 @subsection X Window
20928 @cindex X Window System
20929 @cindex login manager
20930 Support for the X Window graphical display system---specifically
20931 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
20932 there is no @code{xorg-service} procedure. Instead, the X server is
20933 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
20936 @cindex GNOME, login manager
20937 GDM of course allows users to log in into window managers and desktop
20938 environments other than GNOME; for those using GNOME, GDM is required for
20939 features such as automatic screen locking.
20941 @cindex window manager
20942 To use X11, you must install at least one @dfn{window manager}---for
20943 example the @code{windowmaker} or @code{openbox} packages---preferably
20944 by adding it to the @code{packages} field of your operating system
20945 definition (@pxref{operating-system Reference, system-wide packages}).
20947 @anchor{wayland-gdm}
20948 GDM also supports Wayland: it can itself use Wayland instead of X11 for
20949 its user interface, and it can also start Wayland sessions. The former is
20950 required for the latter, to enable, set @code{wayland?} to @code{#t} in
20951 @code{gdm-configuration}.
20953 @defvr {Scheme Variable} gdm-service-type
20954 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
20955 Desktop Manager} (GDM), a program that manages graphical display servers and
20956 handles graphical user logins. Its value must be a @code{gdm-configuration}
20959 @cindex session types
20960 GDM looks for @dfn{session types} described by the @file{.desktop} files in
20961 @file{/run/current-system/profile/share/xsessions} (for X11 sessions) and
20962 @file{/run/current-system/profile/share/wayland-sessions} (for Wayland
20963 sessions) and allows users to choose a session from the log-in screen.
20964 Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
20965 @file{.desktop} files; adding them to the system-wide set of packages
20966 automatically makes them available at the log-in screen.
20968 In addition, @file{~/.xsession} files are honored. When available,
20969 @file{~/.xsession} must be an executable that starts a window manager
20970 and/or other X clients.
20973 @deftp {Data Type} gdm-configuration
20975 @item @code{auto-login?} (default: @code{#f})
20976 @itemx @code{default-user} (default: @code{#f})
20977 When @code{auto-login?} is false, GDM presents a log-in screen.
20979 When @code{auto-login?} is true, GDM logs in directly as
20980 @code{default-user}.
20982 @item @code{debug?} (default: @code{#f})
20983 When true, GDM writes debug messages to its log.
20985 @item @code{gnome-shell-assets} (default: ...)
20986 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
20988 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
20989 Configuration of the Xorg graphical server.
20991 @item @code{xsession} (default: @code{(xinitrc)})
20992 Script to run before starting a X session.
20994 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
20995 File name of the @code{dbus-daemon} executable.
20997 @item @code{gdm} (default: @code{gdm})
20998 The GDM package to use.
21000 @item @code{wayland?} (default: @code{#f})
21001 When true, enables Wayland in GDM, necessary to use Wayland sessions.
21003 @item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
21004 The Wayland session wrapper to use, needed to setup the
21009 @defvr {Scheme Variable} slim-service-type
21010 This is the type for the SLiM graphical login manager for X11.
21012 Like GDM, SLiM looks for session types described by @file{.desktop} files and
21013 allows users to choose a session from the log-in screen using @kbd{F1}. It
21014 also honors @file{~/.xsession} files.
21016 Unlike GDM, SLiM does not spawn the user session on a different VT after
21017 logging in, which means that you can only start one graphical session. If you
21018 want to be able to run multiple graphical sessions at the same time you have
21019 to add multiple SLiM services to your system services. The following example
21020 shows how to replace the default GDM service with two SLiM services on tty7
21024 (use-modules (gnu services)
21025 (gnu services desktop)
21026 (gnu services xorg))
21030 (services (cons* (service slim-service-type (slim-configuration
21033 (service slim-service-type (slim-configuration
21036 (modify-services %desktop-services
21037 (delete gdm-service-type)))))
21042 @deftp {Data Type} slim-configuration
21043 Data type representing the configuration of @code{slim-service-type}.
21046 @item @code{allow-empty-passwords?} (default: @code{#t})
21047 Whether to allow logins with empty passwords.
21049 @item @code{gnupg?} (default: @code{#f})
21050 If enabled, @code{pam-gnupg} will attempt to automatically unlock the
21051 user's GPG keys with the login password via @code{gpg-agent}. The
21052 keygrips of all keys to be unlocked should be written to
21053 @file{~/.pam-gnupg}, and can be queried with @code{gpg -K
21054 --with-keygrip}. Presetting passphrases must be enabled by adding
21055 @code{allow-preset-passphrase} in @file{~/.gnupg/gpg-agent.conf}.
21057 @item @code{auto-login?} (default: @code{#f})
21058 @itemx @code{default-user} (default: @code{""})
21059 When @code{auto-login?} is false, SLiM presents a log-in screen.
21061 When @code{auto-login?} is true, SLiM logs in directly as
21062 @code{default-user}.
21064 @item @code{theme} (default: @code{%default-slim-theme})
21065 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
21066 The graphical theme to use and its name.
21068 @item @code{auto-login-session} (default: @code{#f})
21069 If true, this must be the name of the executable to start as the default
21070 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
21072 If false, a session described by one of the available @file{.desktop}
21073 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
21077 You must install at least one window manager in the system profile or in
21078 your user profile. Failing to do that, if @code{auto-login-session} is
21079 false, you will be unable to log in.
21082 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21083 Configuration of the Xorg graphical server.
21085 @item @code{display} (default @code{":0"})
21086 The display on which to start the Xorg graphical server.
21088 @item @code{vt} (default @code{"vt7"})
21089 The VT on which to start the Xorg graphical server.
21091 @item @code{xauth} (default: @code{xauth})
21092 The XAuth package to use.
21094 @item @code{shepherd} (default: @code{shepherd})
21095 The Shepherd package used when invoking @command{halt} and
21098 @item @code{sessreg} (default: @code{sessreg})
21099 The sessreg package used in order to register the session.
21101 @item @code{slim} (default: @code{slim})
21102 The SLiM package to use.
21106 @defvr {Scheme Variable} %default-theme
21107 @defvrx {Scheme Variable} %default-theme-name
21108 The default SLiM theme and its name.
21112 @cindex login manager
21114 @defvr {Scheme Variable} sddm-service-type
21115 This is the type of the service to run the
21116 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
21117 must be a @code{sddm-configuration} record (see below).
21119 Here's an example use:
21122 (service sddm-service-type
21123 (sddm-configuration
21124 (auto-login-user "alice")
21125 (auto-login-session "xfce.desktop")))
21129 @deftp {Data Type} sddm-configuration
21130 This data type represents the configuration of the SDDM login manager.
21131 The available fields are:
21134 @item @code{sddm} (default: @code{sddm})
21135 The SDDM package to use.
21137 @item @code{display-server} (default: "x11")
21138 Select display server to use for the greeter. Valid values are
21139 @samp{"x11"} or @samp{"wayland"}.
21141 @item @code{numlock} (default: "on")
21142 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
21144 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
21145 Command to run when halting.
21147 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
21148 Command to run when rebooting.
21150 @item @code{theme} (default "maldives")
21151 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
21152 @samp{"maldives"} or @samp{"maya"}.
21154 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
21155 Directory to look for themes.
21157 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
21158 Directory to look for faces.
21160 @item @code{default-path} (default "/run/current-system/profile/bin")
21161 Default PATH to use.
21163 @item @code{minimum-uid} (default: 1000)
21164 Minimum UID displayed in SDDM and allowed for log-in.
21166 @item @code{maximum-uid} (default: 2000)
21167 Maximum UID to display in SDDM.
21169 @item @code{remember-last-user?} (default #t)
21170 Remember last user.
21172 @item @code{remember-last-session?} (default #t)
21173 Remember last session.
21175 @item @code{hide-users} (default "")
21176 Usernames to hide from SDDM greeter.
21178 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
21179 Users with shells listed will be hidden from the SDDM greeter.
21181 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
21182 Script to run before starting a wayland session.
21184 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
21185 Directory to look for desktop files starting wayland sessions.
21187 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21188 Configuration of the Xorg graphical server.
21190 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
21193 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
21196 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
21197 Script to run after starting xorg-server.
21199 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
21200 Script to run before stopping xorg-server.
21202 @item @code{xsession-command} (default: @code{xinitrc})
21203 Script to run before starting a X session.
21205 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
21206 Directory to look for desktop files starting X sessions.
21208 @item @code{minimum-vt} (default: 7)
21211 @item @code{auto-login-user} (default "")
21212 User account that will be automatically logged in.
21213 Setting this to the empty string disables auto-login.
21215 @item @code{auto-login-session} (default "")
21216 The @file{.desktop} file name to use as the auto-login session, or the empty string.
21218 @item @code{relogin?} (default #f)
21219 Relogin after logout.
21225 @cindex Xorg, configuration
21226 @deftp {Data Type} xorg-configuration
21227 This data type represents the configuration of the Xorg graphical display
21228 server. Note that there is no Xorg service; instead, the X server is started
21229 by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
21230 of these display managers aggregates an @code{xorg-configuration} record.
21233 @item @code{modules} (default: @code{%default-xorg-modules})
21234 This is a list of @dfn{module packages} loaded by the Xorg
21235 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
21237 @item @code{fonts} (default: @code{%default-xorg-fonts})
21238 This is a list of font directories to add to the server's @dfn{font path}.
21240 @item @code{drivers} (default: @code{'()})
21241 This must be either the empty list, in which case Xorg chooses a graphics
21242 driver automatically, or a list of driver names that will be tried in this
21243 order---e.g., @code{("modesetting" "vesa")}.
21245 @item @code{resolutions} (default: @code{'()})
21246 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
21247 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
21250 @cindex keyboard layout, for Xorg
21251 @cindex keymap, for Xorg
21252 @item @code{keyboard-layout} (default: @code{#f})
21253 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
21254 English (``qwerty'') for a 105-key PC keyboard.
21256 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
21257 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
21258 information on how to specify the keyboard layout.
21260 @item @code{extra-config} (default: @code{'()})
21261 This is a list of strings or objects appended to the configuration file. It
21262 is used to pass extra text to be added verbatim to the configuration file.
21264 @item @code{server} (default: @code{xorg-server})
21265 This is the package providing the Xorg server.
21267 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
21268 This is the list of command-line arguments to pass to the X server. The
21269 default is @code{-nolisten tcp}.
21273 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
21274 [@var{login-manager-service-type}]
21275 Tell the log-in manager (of type @var{login-manager-service-type}) to use
21276 @var{config}, an @code{<xorg-configuration>} record.
21278 Since the Xorg configuration is embedded in the log-in manager's
21279 configuration---e.g., @code{gdm-configuration}---this procedure provides a
21280 shorthand to set the Xorg configuration.
21283 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
21284 Return a @code{startx} script in which the modules, fonts, etc. specified
21285 in @var{config}, are available. The result should be used in place of
21288 Usually the X server is started by a login manager.
21292 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
21293 Add @var{package}, a package for a screen locker or screen saver whose
21294 command is @var{program}, to the set of setuid programs and add a PAM entry
21295 for it. For example:
21298 (screen-locker-service xlockmore "xlock")
21301 makes the good ol' XlockMore usable.
21305 @node Printing Services
21306 @subsection Printing Services
21308 @cindex printer support with CUPS
21309 The @code{(gnu services cups)} module provides a Guix service definition
21310 for the CUPS printing service. To add printer support to a Guix
21311 system, add a @code{cups-service} to the operating system definition:
21313 @deffn {Scheme Variable} cups-service-type
21314 The service type for the CUPS print server. Its value should be a valid
21315 CUPS configuration (see below). To use the default settings, simply
21318 (service cups-service-type)
21322 The CUPS configuration controls the basic things about your CUPS
21323 installation: what interfaces it listens on, what to do if a print job
21324 fails, how much logging to do, and so on. To actually add a printer,
21325 you have to visit the @url{http://localhost:631} URL, or use a tool such
21326 as GNOME's printer configuration services. By default, configuring a
21327 CUPS service will generate a self-signed certificate if needed, for
21328 secure connections to the print server.
21330 Suppose you want to enable the Web interface of CUPS and also add
21331 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
21332 package and for HP printers @i{via} the @code{hplip-minimal} package.
21333 You can do that directly, like this (you need to use the
21334 @code{(gnu packages cups)} module):
21337 (service cups-service-type
21338 (cups-configuration
21339 (web-interface? #t)
21341 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
21345 If you wish to use the Qt5 based GUI which comes with the hplip
21346 package then it is suggested that you install the @code{hplip} package,
21347 either in your OS configuration file or as your user.
21350 The available configuration parameters follow. Each parameter
21351 definition is preceded by its type; for example, @samp{string-list foo}
21352 indicates that the @code{foo} parameter should be specified as a list of
21353 strings. There is also a way to specify the configuration as a string,
21354 if you have an old @code{cupsd.conf} file that you want to port over
21355 from some other system; see the end for more details.
21357 @c The following documentation was initially generated by
21358 @c (generate-documentation) in (gnu services cups). Manually maintained
21359 @c documentation is better, so we shouldn't hesitate to edit below as
21360 @c needed. However if the change you want to make to this documentation
21361 @c can be done in an automated way, it's probably easier to change
21362 @c (generate-documentation) than to make it below and have to deal with
21363 @c the churn as CUPS updates.
21366 Available @code{cups-configuration} fields are:
21368 @deftypevr {@code{cups-configuration} parameter} package cups
21372 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
21373 Drivers and other extensions to the CUPS package.
21376 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
21377 Configuration of where to write logs, what directories to use for print
21378 spools, and related privileged configuration parameters.
21380 Available @code{files-configuration} fields are:
21382 @deftypevr {@code{files-configuration} parameter} log-location access-log
21383 Defines the access log filename. Specifying a blank filename disables
21384 access log generation. The value @code{stderr} causes log entries to be
21385 sent to the standard error file when the scheduler is running in the
21386 foreground, or to the system log daemon when run in the background. The
21387 value @code{syslog} causes log entries to be sent to the system log
21388 daemon. The server name may be included in filenames using the string
21389 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
21391 Defaults to @samp{"/var/log/cups/access_log"}.
21394 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
21395 Where CUPS should cache data.
21397 Defaults to @samp{"/var/cache/cups"}.
21400 @deftypevr {@code{files-configuration} parameter} string config-file-perm
21401 Specifies the permissions for all configuration files that the scheduler
21404 Note that the permissions for the printers.conf file are currently
21405 masked to only allow access from the scheduler user (typically root).
21406 This is done because printer device URIs sometimes contain sensitive
21407 authentication information that should not be generally known on the
21408 system. There is no way to disable this security feature.
21410 Defaults to @samp{"0640"}.
21413 @deftypevr {@code{files-configuration} parameter} log-location error-log
21414 Defines the error log filename. Specifying a blank filename disables
21415 error log generation. The value @code{stderr} causes log entries to be
21416 sent to the standard error file when the scheduler is running in the
21417 foreground, or to the system log daemon when run in the background. The
21418 value @code{syslog} causes log entries to be sent to the system log
21419 daemon. The server name may be included in filenames using the string
21420 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
21422 Defaults to @samp{"/var/log/cups/error_log"}.
21425 @deftypevr {@code{files-configuration} parameter} string fatal-errors
21426 Specifies which errors are fatal, causing the scheduler to exit. The
21431 No errors are fatal.
21434 All of the errors below are fatal.
21437 Browsing initialization errors are fatal, for example failed connections
21438 to the DNS-SD daemon.
21441 Configuration file syntax errors are fatal.
21444 Listen or Port errors are fatal, except for IPv6 failures on the
21445 loopback or @code{any} addresses.
21448 Log file creation or write errors are fatal.
21451 Bad startup file permissions are fatal, for example shared TLS
21452 certificate and key files with world-read permissions.
21455 Defaults to @samp{"all -browse"}.
21458 @deftypevr {@code{files-configuration} parameter} boolean file-device?
21459 Specifies whether the file pseudo-device can be used for new printer
21460 queues. The URI @uref{file:///dev/null} is always allowed.
21462 Defaults to @samp{#f}.
21465 @deftypevr {@code{files-configuration} parameter} string group
21466 Specifies the group name or ID that will be used when executing external
21469 Defaults to @samp{"lp"}.
21472 @deftypevr {@code{files-configuration} parameter} string log-file-group
21473 Specifies the group name or ID that will be used for log files.
21475 Defaults to @samp{"lpadmin"}.
21478 @deftypevr {@code{files-configuration} parameter} string log-file-perm
21479 Specifies the permissions for all log files that the scheduler writes.
21481 Defaults to @samp{"0644"}.
21484 @deftypevr {@code{files-configuration} parameter} log-location page-log
21485 Defines the page log filename. Specifying a blank filename disables
21486 page log generation. The value @code{stderr} causes log entries to be
21487 sent to the standard error file when the scheduler is running in the
21488 foreground, or to the system log daemon when run in the background. The
21489 value @code{syslog} causes log entries to be sent to the system log
21490 daemon. The server name may be included in filenames using the string
21491 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
21493 Defaults to @samp{"/var/log/cups/page_log"}.
21496 @deftypevr {@code{files-configuration} parameter} string remote-root
21497 Specifies the username that is associated with unauthenticated accesses
21498 by clients claiming to be the root user. The default is @code{remroot}.
21500 Defaults to @samp{"remroot"}.
21503 @deftypevr {@code{files-configuration} parameter} file-name request-root
21504 Specifies the directory that contains print jobs and other HTTP request
21507 Defaults to @samp{"/var/spool/cups"}.
21510 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
21511 Specifies the level of security sandboxing that is applied to print
21512 filters, backends, and other child processes of the scheduler; either
21513 @code{relaxed} or @code{strict}. This directive is currently only
21514 used/supported on macOS.
21516 Defaults to @samp{strict}.
21519 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
21520 Specifies the location of TLS certificates and private keys. CUPS will
21521 look for public and private keys in this directory: @file{.crt} files
21522 for PEM-encoded certificates and corresponding @file{.key} files for
21523 PEM-encoded private keys.
21525 Defaults to @samp{"/etc/cups/ssl"}.
21528 @deftypevr {@code{files-configuration} parameter} file-name server-root
21529 Specifies the directory containing the server configuration files.
21531 Defaults to @samp{"/etc/cups"}.
21534 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
21535 Specifies whether the scheduler calls fsync(2) after writing
21536 configuration or state files.
21538 Defaults to @samp{#f}.
21541 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
21542 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
21545 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
21546 Specifies the directory where temporary files are stored.
21548 Defaults to @samp{"/var/spool/cups/tmp"}.
21551 @deftypevr {@code{files-configuration} parameter} string user
21552 Specifies the user name or ID that is used when running external
21555 Defaults to @samp{"lp"}.
21558 @deftypevr {@code{files-configuration} parameter} string set-env
21559 Set the specified environment variable to be passed to child processes.
21561 Defaults to @samp{"variable value"}.
21565 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
21566 Specifies the logging level for the AccessLog file. The @code{config}
21567 level logs when printers and classes are added, deleted, or modified and
21568 when configuration files are accessed or updated. The @code{actions}
21569 level logs when print jobs are submitted, held, released, modified, or
21570 canceled, and any of the conditions for @code{config}. The @code{all}
21571 level logs all requests.
21573 Defaults to @samp{actions}.
21576 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
21577 Specifies whether to purge job history data automatically when it is no
21578 longer required for quotas.
21580 Defaults to @samp{#f}.
21583 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
21584 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
21585 For example, @samp{"_cups" "_print"} will tell network clients that both
21586 CUPS sharing and IPP Everywhere are supported.
21588 Defaults to @samp{"_cups"}.
21591 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
21592 Specifies which protocols to use for local printer sharing.
21594 Defaults to @samp{dnssd}.
21597 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
21598 Specifies whether the CUPS web interface is advertised.
21600 Defaults to @samp{#f}.
21603 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
21604 Specifies whether shared printers are advertised.
21606 Defaults to @samp{#f}.
21609 @deftypevr {@code{cups-configuration} parameter} string classification
21610 Specifies the security classification of the server. Any valid banner
21611 name can be used, including @samp{"classified"}, @samp{"confidential"},
21612 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
21613 banner can be omitted to disable secure printing functions.
21615 Defaults to @samp{""}.
21618 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
21619 Specifies whether users may override the classification (cover page) of
21620 individual print jobs using the @code{job-sheets} option.
21622 Defaults to @samp{#f}.
21625 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
21626 Specifies the default type of authentication to use.
21628 Defaults to @samp{Basic}.
21631 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
21632 Specifies whether encryption will be used for authenticated requests.
21634 Defaults to @samp{Required}.
21637 @deftypevr {@code{cups-configuration} parameter} string default-language
21638 Specifies the default language to use for text and web content.
21640 Defaults to @samp{"en"}.
21643 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
21644 Specifies the default paper size for new print queues. @samp{"Auto"}
21645 uses a locale-specific default, while @samp{"None"} specifies there is
21646 no default paper size. Specific size names are typically
21647 @samp{"Letter"} or @samp{"A4"}.
21649 Defaults to @samp{"Auto"}.
21652 @deftypevr {@code{cups-configuration} parameter} string default-policy
21653 Specifies the default access policy to use.
21655 Defaults to @samp{"default"}.
21658 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
21659 Specifies whether local printers are shared by default.
21661 Defaults to @samp{#t}.
21664 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
21665 Specifies the delay for updating of configuration and state files, in
21666 seconds. A value of 0 causes the update to happen as soon as possible,
21667 typically within a few milliseconds.
21669 Defaults to @samp{30}.
21672 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
21673 Specifies what to do when an error occurs. Possible values are
21674 @code{abort-job}, which will discard the failed print job;
21675 @code{retry-job}, which will retry the job at a later time;
21676 @code{retry-current-job}, which retries the failed job immediately; and
21677 @code{stop-printer}, which stops the printer.
21679 Defaults to @samp{stop-printer}.
21682 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
21683 Specifies the maximum cost of filters that are run concurrently, which
21684 can be used to minimize disk, memory, and CPU resource problems. A
21685 limit of 0 disables filter limiting. An average print to a
21686 non-PostScript printer needs a filter limit of about 200. A PostScript
21687 printer needs about half that (100). Setting the limit below these
21688 thresholds will effectively limit the scheduler to printing a single job
21691 Defaults to @samp{0}.
21694 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
21695 Specifies the scheduling priority of filters that are run to print a
21696 job. The nice value ranges from 0, the highest priority, to 19, the
21699 Defaults to @samp{0}.
21702 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
21703 Specifies whether to do reverse lookups on connecting clients. The
21704 @code{double} setting causes @code{cupsd} to verify that the hostname
21705 resolved from the address matches one of the addresses returned for that
21706 hostname. Double lookups also prevent clients with unregistered
21707 addresses from connecting to your server. Only set this option to
21708 @code{#t} or @code{double} if absolutely required.
21710 Defaults to @samp{#f}.
21713 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
21714 Specifies the number of seconds to wait before killing the filters and
21715 backend associated with a canceled or held job.
21717 Defaults to @samp{30}.
21720 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
21721 Specifies the interval between retries of jobs in seconds. This is
21722 typically used for fax queues but can also be used with normal print
21723 queues whose error policy is @code{retry-job} or
21724 @code{retry-current-job}.
21726 Defaults to @samp{30}.
21729 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
21730 Specifies the number of retries that are done for jobs. This is
21731 typically used for fax queues but can also be used with normal print
21732 queues whose error policy is @code{retry-job} or
21733 @code{retry-current-job}.
21735 Defaults to @samp{5}.
21738 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
21739 Specifies whether to support HTTP keep-alive connections.
21741 Defaults to @samp{#t}.
21744 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
21745 Specifies the maximum size of print files, IPP requests, and HTML form
21746 data. A limit of 0 disables the limit check.
21748 Defaults to @samp{0}.
21751 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
21752 Listens on the specified interfaces for connections. Valid values are
21753 of the form @var{address}:@var{port}, where @var{address} is either an
21754 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
21755 indicate all addresses. Values can also be file names of local UNIX
21756 domain sockets. The Listen directive is similar to the Port directive
21757 but allows you to restrict access to specific interfaces or networks.
21760 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
21761 Specifies the number of pending connections that will be allowed. This
21762 normally only affects very busy servers that have reached the MaxClients
21763 limit, but can also be triggered by large numbers of simultaneous
21764 connections. When the limit is reached, the operating system will
21765 refuse additional connections until the scheduler can accept the pending
21768 Defaults to @samp{128}.
21771 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
21772 Specifies a set of additional access controls.
21774 Available @code{location-access-controls} fields are:
21776 @deftypevr {@code{location-access-controls} parameter} file-name path
21777 Specifies the URI path to which the access control applies.
21780 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
21781 Access controls for all access to this path, in the same format as the
21782 @code{access-controls} of @code{operation-access-control}.
21784 Defaults to @samp{()}.
21787 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
21788 Access controls for method-specific access to this path.
21790 Defaults to @samp{()}.
21792 Available @code{method-access-controls} fields are:
21794 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
21795 If @code{#t}, apply access controls to all methods except the listed
21796 methods. Otherwise apply to only the listed methods.
21798 Defaults to @samp{#f}.
21801 @deftypevr {@code{method-access-controls} parameter} method-list methods
21802 Methods to which this access control applies.
21804 Defaults to @samp{()}.
21807 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
21808 Access control directives, as a list of strings. Each string should be
21809 one directive, such as @samp{"Order allow,deny"}.
21811 Defaults to @samp{()}.
21816 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
21817 Specifies the number of debugging messages that are retained for logging
21818 if an error occurs in a print job. Debug messages are logged regardless
21819 of the LogLevel setting.
21821 Defaults to @samp{100}.
21824 @deftypevr {@code{cups-configuration} parameter} log-level log-level
21825 Specifies the level of logging for the ErrorLog file. The value
21826 @code{none} stops all logging while @code{debug2} logs everything.
21828 Defaults to @samp{info}.
21831 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
21832 Specifies the format of the date and time in the log files. The value
21833 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
21835 Defaults to @samp{standard}.
21838 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
21839 Specifies the maximum number of simultaneous clients that are allowed by
21842 Defaults to @samp{100}.
21845 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
21846 Specifies the maximum number of simultaneous clients that are allowed
21847 from a single address.
21849 Defaults to @samp{100}.
21852 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
21853 Specifies the maximum number of copies that a user can print of each
21856 Defaults to @samp{9999}.
21859 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
21860 Specifies the maximum time a job may remain in the @code{indefinite}
21861 hold state before it is canceled. A value of 0 disables cancellation of
21864 Defaults to @samp{0}.
21867 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
21868 Specifies the maximum number of simultaneous jobs that are allowed. Set
21869 to 0 to allow an unlimited number of jobs.
21871 Defaults to @samp{500}.
21874 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
21875 Specifies the maximum number of simultaneous jobs that are allowed per
21876 printer. A value of 0 allows up to MaxJobs jobs per printer.
21878 Defaults to @samp{0}.
21881 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
21882 Specifies the maximum number of simultaneous jobs that are allowed per
21883 user. A value of 0 allows up to MaxJobs jobs per user.
21885 Defaults to @samp{0}.
21888 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
21889 Specifies the maximum time a job may take to print before it is
21890 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
21892 Defaults to @samp{10800}.
21895 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
21896 Specifies the maximum size of the log files before they are rotated, in
21897 bytes. The value 0 disables log rotation.
21899 Defaults to @samp{1048576}.
21902 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
21903 Specifies the maximum amount of time to allow between files in a
21904 multiple file print job, in seconds.
21906 Defaults to @samp{900}.
21909 @deftypevr {@code{cups-configuration} parameter} string page-log-format
21910 Specifies the format of PageLog lines. Sequences beginning with percent
21911 (@samp{%}) characters are replaced with the corresponding information,
21912 while all other characters are copied literally. The following percent
21913 sequences are recognized:
21917 insert a single percent character
21920 insert the value of the specified IPP attribute
21923 insert the number of copies for the current page
21926 insert the current page number
21929 insert the current date and time in common log format
21935 insert the printer name
21938 insert the username
21941 A value of the empty string disables page logging. The string @code{%p
21942 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
21943 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
21946 Defaults to @samp{""}.
21949 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
21950 Passes the specified environment variable(s) to child processes; a list
21953 Defaults to @samp{()}.
21956 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
21957 Specifies named access control policies.
21959 Available @code{policy-configuration} fields are:
21961 @deftypevr {@code{policy-configuration} parameter} string name
21962 Name of the policy.
21965 @deftypevr {@code{policy-configuration} parameter} string job-private-access
21966 Specifies an access list for a job's private values. @code{@@ACL} maps
21967 to the printer's requesting-user-name-allowed or
21968 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
21969 owner. @code{@@SYSTEM} maps to the groups listed for the
21970 @code{system-group} field of the @code{files-configuration},
21971 which is reified into the @code{cups-files.conf(5)} file. Other
21972 possible elements of the access list include specific user names, and
21973 @code{@@@var{group}} to indicate members of a specific group. The
21974 access list may also be simply @code{all} or @code{default}.
21976 Defaults to @samp{"@@OWNER @@SYSTEM"}.
21979 @deftypevr {@code{policy-configuration} parameter} string job-private-values
21980 Specifies the list of job values to make private, or @code{all},
21981 @code{default}, or @code{none}.
21983 Defaults to @samp{"job-name job-originating-host-name
21984 job-originating-user-name phone"}.
21987 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
21988 Specifies an access list for a subscription's private values.
21989 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
21990 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
21991 owner. @code{@@SYSTEM} maps to the groups listed for the
21992 @code{system-group} field of the @code{files-configuration},
21993 which is reified into the @code{cups-files.conf(5)} file. Other
21994 possible elements of the access list include specific user names, and
21995 @code{@@@var{group}} to indicate members of a specific group. The
21996 access list may also be simply @code{all} or @code{default}.
21998 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22001 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
22002 Specifies the list of job values to make private, or @code{all},
22003 @code{default}, or @code{none}.
22005 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
22006 notify-subscriber-user-name notify-user-data"}.
22009 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
22010 Access control by IPP operation.
22012 Defaults to @samp{()}.
22016 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
22017 Specifies whether job files (documents) are preserved after a job is
22018 printed. If a numeric value is specified, job files are preserved for
22019 the indicated number of seconds after printing. Otherwise a boolean
22020 value applies indefinitely.
22022 Defaults to @samp{86400}.
22025 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
22026 Specifies whether the job history is preserved after a job is printed.
22027 If a numeric value is specified, the job history is preserved for the
22028 indicated number of seconds after printing. If @code{#t}, the job
22029 history is preserved until the MaxJobs limit is reached.
22031 Defaults to @samp{#t}.
22034 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
22035 Specifies the amount of time to wait for job completion before
22036 restarting the scheduler.
22038 Defaults to @samp{30}.
22041 @deftypevr {@code{cups-configuration} parameter} string rip-cache
22042 Specifies the maximum amount of memory to use when converting documents
22043 into bitmaps for a printer.
22045 Defaults to @samp{"128m"}.
22048 @deftypevr {@code{cups-configuration} parameter} string server-admin
22049 Specifies the email address of the server administrator.
22051 Defaults to @samp{"root@@localhost.localdomain"}.
22054 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
22055 The ServerAlias directive is used for HTTP Host header validation when
22056 clients connect to the scheduler from external interfaces. Using the
22057 special name @code{*} can expose your system to known browser-based DNS
22058 rebinding attacks, even when accessing sites through a firewall. If the
22059 auto-discovery of alternate names does not work, we recommend listing
22060 each alternate name with a ServerAlias directive instead of using
22063 Defaults to @samp{*}.
22066 @deftypevr {@code{cups-configuration} parameter} string server-name
22067 Specifies the fully-qualified host name of the server.
22069 Defaults to @samp{"localhost"}.
22072 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
22073 Specifies what information is included in the Server header of HTTP
22074 responses. @code{None} disables the Server header. @code{ProductOnly}
22075 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
22076 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
22077 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
22078 the output of the @code{uname} command. @code{Full} reports @code{CUPS
22079 2.0.0 (@var{uname}) IPP/2.0}.
22081 Defaults to @samp{Minimal}.
22084 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
22085 Listens on the specified interfaces for encrypted connections. Valid
22086 values are of the form @var{address}:@var{port}, where @var{address} is
22087 either an IPv6 address enclosed in brackets, an IPv4 address, or
22088 @code{*} to indicate all addresses.
22090 Defaults to @samp{()}.
22093 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
22094 Sets encryption options. By default, CUPS only supports encryption
22095 using TLS v1.0 or higher using known secure cipher suites. Security is
22096 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
22097 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
22098 suites, which are required for some older clients. The @code{AllowSSL3} option
22099 enables SSL v3.0, which is required for some older clients that do not support
22100 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
22101 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
22102 protocol version to TLS v1.1.
22104 Defaults to @samp{()}.
22107 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
22108 Specifies whether the scheduler requires clients to strictly adhere to
22109 the IPP specifications.
22111 Defaults to @samp{#f}.
22114 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
22115 Specifies the HTTP request timeout, in seconds.
22117 Defaults to @samp{900}.
22121 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
22122 Specifies whether the web interface is enabled.
22124 Defaults to @samp{#f}.
22127 At this point you're probably thinking ``oh dear, Guix manual, I like
22128 you but you can stop already with the configuration options''. Indeed.
22129 However, one more point: it could be that you have an existing
22130 @code{cupsd.conf} that you want to use. In that case, you can pass an
22131 @code{opaque-cups-configuration} as the configuration of a
22132 @code{cups-service-type}.
22134 Available @code{opaque-cups-configuration} fields are:
22136 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
22140 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
22141 The contents of the @code{cupsd.conf}, as a string.
22144 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
22145 The contents of the @code{cups-files.conf} file, as a string.
22148 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
22149 strings of the same name, you could instantiate a CUPS service like
22153 (service cups-service-type
22154 (opaque-cups-configuration
22155 (cupsd.conf cupsd.conf)
22156 (cups-files.conf cups-files.conf)))
22160 @node Desktop Services
22161 @subsection Desktop Services
22163 The @code{(gnu services desktop)} module provides services that are
22164 usually useful in the context of a ``desktop'' setup---that is, on a
22165 machine running a graphical display server, possibly with graphical user
22166 interfaces, etc. It also defines services that provide specific desktop
22167 environments like GNOME, Xfce or MATE.
22169 To simplify things, the module defines a variable containing the set of
22170 services that users typically expect on a machine with a graphical
22171 environment and networking:
22173 @defvr {Scheme Variable} %desktop-services
22174 This is a list of services that builds upon @code{%base-services} and
22175 adds or adjusts services for a typical ``desktop'' setup.
22177 In particular, it adds a graphical login manager (@pxref{X Window,
22178 @code{gdm-service-type}}), screen lockers, a network management tool
22179 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
22180 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
22181 energy and color management services, the @code{elogind} login and seat
22182 manager, the Polkit privilege service, the GeoClue location service, the
22183 AccountsService daemon that allows authorized users change system passwords,
22184 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
22185 name service switch service configured to be able to use @code{nss-mdns}
22186 (@pxref{Name Service Switch, mDNS}).
22189 The @code{%desktop-services} variable can be used as the @code{services}
22190 field of an @code{operating-system} declaration (@pxref{operating-system
22191 Reference, @code{services}}).
22193 Additionally, the @code{gnome-desktop-service-type},
22194 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
22195 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
22196 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
22197 ``add GNOME'' means that system-level services like the backlight adjustment
22198 helpers and the power management utilities are added to the system, extending
22199 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
22200 elevated privileges on a limited number of special-purpose system interfaces.
22201 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
22202 the GNOME metapackage to the system profile. Likewise, adding the Xfce
22203 service not only adds the @code{xfce} metapackage to the system profile, but
22204 it also gives the Thunar file manager the ability to open a ``root-mode'' file
22205 management window, if the user authenticates using the administrator's
22206 password via the standard polkit graphical interface. To ``add MATE'' means
22207 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
22208 to operate with elevated privileges on a limited number of special-purpose
22209 system interfaces. Additionally, adding a service of type
22210 @code{mate-desktop-service-type} adds the MATE metapackage to the system
22211 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
22212 appropriately, and several of Enlightenment's binaries are set as setuid,
22213 allowing Enlightenment's screen locker and other functionality to work as
22216 The desktop environments in Guix use the Xorg display server by
22217 default. If you'd like to use the newer display server protocol
22218 called Wayland, you need to enable Wayland support in GDM
22219 (@pxref{wayland-gdm}). Another solution is to use the
22220 @code{sddm-service} instead of GDM as the graphical login manager.
22221 You should then select the ``GNOME (Wayland)'' session in SDDM@.
22222 Alternatively you can also try starting GNOME on Wayland manually from a
22223 TTY with the command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
22224 gnome-session``. Currently only GNOME has support for Wayland.
22226 @defvr {Scheme Variable} gnome-desktop-service-type
22227 This is the type of the service that adds the @uref{https://www.gnome.org,
22228 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
22229 object (see below).
22231 This service adds the @code{gnome} package to the system profile, and extends
22232 polkit with the actions from @code{gnome-settings-daemon}.
22235 @deftp {Data Type} gnome-desktop-configuration
22236 Configuration record for the GNOME desktop environment.
22239 @item @code{gnome} (default: @code{gnome})
22240 The GNOME package to use.
22244 @defvr {Scheme Variable} xfce-desktop-service-type
22245 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
22246 desktop environment. Its value is an @code{xfce-desktop-configuration} object
22249 This service adds the @code{xfce} package to the system profile, and
22250 extends polkit with the ability for @code{thunar} to manipulate the file
22251 system as root from within a user session, after the user has authenticated
22252 with the administrator's password.
22254 Note that @code{xfce4-panel} and its plugin packages should be installed in
22255 the same profile to ensure compatibility. When using this service, you should
22256 add extra plugins (@code{xfce4-whiskermenu-plugin},
22257 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
22258 @code{operating-system}.
22261 @deftp {Data Type} xfce-desktop-configuration
22262 Configuration record for the Xfce desktop environment.
22265 @item @code{xfce} (default: @code{xfce})
22266 The Xfce package to use.
22270 @deffn {Scheme Variable} mate-desktop-service-type
22271 This is the type of the service that runs the @uref{https://mate-desktop.org/,
22272 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
22273 object (see below).
22275 This service adds the @code{mate} package to the system
22276 profile, and extends polkit with the actions from
22277 @code{mate-settings-daemon}.
22280 @deftp {Data Type} mate-desktop-configuration
22281 Configuration record for the MATE desktop environment.
22284 @item @code{mate} (default: @code{mate})
22285 The MATE package to use.
22289 @deffn {Scheme Variable} lxqt-desktop-service-type
22290 This is the type of the service that runs the @uref{https://lxqt-project.org,
22291 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
22292 object (see below).
22294 This service adds the @code{lxqt} package to the system
22298 @deftp {Data Type} lxqt-desktop-configuration
22299 Configuration record for the LXQt desktop environment.
22302 @item @code{lxqt} (default: @code{lxqt})
22303 The LXQT package to use.
22307 @deffn {Scheme Variable} enlightenment-desktop-service-type
22308 Return a service that adds the @code{enlightenment} package to the system
22309 profile, and extends dbus with actions from @code{efl}.
22312 @deftp {Data Type} enlightenment-desktop-service-configuration
22314 @item @code{enlightenment} (default: @code{enlightenment})
22315 The enlightenment package to use.
22319 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
22320 the default @code{%desktop-services} variable doesn't include any of
22321 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
22322 @code{%desktop-services} in the @code{services} field of your
22323 @code{operating-system}:
22326 (use-modules (gnu))
22327 (use-service-modules desktop)
22330 ;; cons* adds items to the list given as its last argument.
22331 (services (cons* (service gnome-desktop-service-type)
22332 (service xfce-desktop-service)
22333 %desktop-services))
22337 These desktop environments will then be available as options in the
22338 graphical login window.
22340 The actual service definitions included in @code{%desktop-services} and
22341 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
22342 are described below.
22344 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()] @
22346 Return a service that runs the ``system bus'', using @var{dbus}, with
22347 support for @var{services}. When @var{verbose?} is true, it causes the
22348 @samp{DBUS_VERBOSE} environment variable to be set to @samp{1}; a
22349 verbose-enabled D-Bus package such as @code{dbus-verbose} should be
22350 provided as @var{dbus} in this scenario. The verbose output is logged
22351 to @file{/var/log/dbus-daemon.log}.
22353 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
22354 facility. Its system bus is used to allow system services to communicate
22355 and to be notified of system-wide events.
22357 @var{services} must be a list of packages that provide an
22358 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
22359 and policy files. For example, to allow avahi-daemon to use the system bus,
22360 @var{services} must be equal to @code{(list avahi)}.
22363 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
22364 Return a service that runs the @code{elogind} login and
22365 seat management daemon. @uref{https://github.com/elogind/elogind,
22366 Elogind} exposes a D-Bus interface that can be used to know which users
22367 are logged in, know what kind of sessions they have open, suspend the
22368 system, inhibit system suspend, reboot the system, and other tasks.
22370 Elogind handles most system-level power events for a computer, for
22371 example suspending the system when a lid is closed, or shutting it down
22372 when the power button is pressed.
22374 The @var{config} keyword argument specifies the configuration for
22375 elogind, and should be the result of an @code{(elogind-configuration
22376 (@var{parameter} @var{value})...)} invocation. Available parameters and
22377 their default values are:
22380 @item kill-user-processes?
22382 @item kill-only-users
22384 @item kill-exclude-users
22386 @item inhibit-delay-max-seconds
22388 @item handle-power-key
22390 @item handle-suspend-key
22392 @item handle-hibernate-key
22394 @item handle-lid-switch
22396 @item handle-lid-switch-docked
22398 @item handle-lid-switch-external-power
22400 @item power-key-ignore-inhibited?
22402 @item suspend-key-ignore-inhibited?
22404 @item hibernate-key-ignore-inhibited?
22406 @item lid-switch-ignore-inhibited?
22408 @item holdoff-timeout-seconds
22412 @item idle-action-seconds
22414 @item runtime-directory-size-percent
22416 @item runtime-directory-size
22420 @item suspend-state
22421 @code{("mem" "standby" "freeze")}
22424 @item hibernate-state
22426 @item hibernate-mode
22427 @code{("platform" "shutdown")}
22428 @item hybrid-sleep-state
22430 @item hybrid-sleep-mode
22431 @code{("suspend" "platform" "shutdown")}
22435 @deffn {Scheme Procedure} accountsservice-service @
22436 [#:accountsservice @var{accountsservice}]
22437 Return a service that runs AccountsService, a system service that can
22438 list available accounts, change their passwords, and so on.
22439 AccountsService integrates with PolicyKit to enable unprivileged users
22440 to acquire the capability to modify their system configuration.
22441 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
22442 accountsservice web site} for more information.
22444 The @var{accountsservice} keyword argument is the @code{accountsservice}
22445 package to expose as a service.
22448 @deffn {Scheme Procedure} polkit-service @
22449 [#:polkit @var{polkit}]
22450 Return a service that runs the
22451 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
22452 management service}, which allows system administrators to grant access to
22453 privileged operations in a structured way. By querying the Polkit service, a
22454 privileged system component can know when it should grant additional
22455 capabilities to ordinary users. For example, an ordinary user can be granted
22456 the capability to suspend the system if the user is logged in locally.
22459 @defvr {Scheme Variable} polkit-wheel-service
22460 Service that adds the @code{wheel} group as admins to the Polkit
22461 service. This makes it so that users in the @code{wheel} group are queried
22462 for their own passwords when performing administrative actions instead of
22463 @code{root}'s, similar to the behaviour used by @code{sudo}.
22466 @defvr {Scheme Variable} upower-service-type
22467 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
22468 system-wide monitor for power consumption and battery levels, with the given
22469 configuration settings.
22471 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
22472 notably used by GNOME.
22475 @deftp {Data Type} upower-configuration
22476 Data type representation the configuration for UPower.
22480 @item @code{upower} (default: @var{upower})
22481 Package to use for @code{upower}.
22483 @item @code{watts-up-pro?} (default: @code{#f})
22484 Enable the Watts Up Pro device.
22486 @item @code{poll-batteries?} (default: @code{#t})
22487 Enable polling the kernel for battery level changes.
22489 @item @code{ignore-lid?} (default: @code{#f})
22490 Ignore the lid state, this can be useful if it's incorrect on a device.
22492 @item @code{use-percentage-for-policy?} (default: @code{#f})
22493 Whether battery percentage based policy should be used. The default is to use
22494 the time left, change to @code{#t} to use the percentage.
22496 @item @code{percentage-low} (default: @code{10})
22497 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22498 at which the battery is considered low.
22500 @item @code{percentage-critical} (default: @code{3})
22501 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22502 at which the battery is considered critical.
22504 @item @code{percentage-action} (default: @code{2})
22505 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22506 at which action will be taken.
22508 @item @code{time-low} (default: @code{1200})
22509 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22510 seconds at which the battery is considered low.
22512 @item @code{time-critical} (default: @code{300})
22513 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22514 seconds at which the battery is considered critical.
22516 @item @code{time-action} (default: @code{120})
22517 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22518 seconds at which action will be taken.
22520 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
22521 The action taken when @code{percentage-action} or @code{time-action} is
22522 reached (depending on the configuration of @code{use-percentage-for-policy?}).
22524 Possible values are:
22534 @code{'hybrid-sleep}.
22540 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
22541 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
22542 UDisks}, a @dfn{disk management} daemon that provides user interfaces
22543 with notifications and ways to mount/unmount disks. Programs that talk
22544 to UDisks include the @command{udisksctl} command, part of UDisks, and
22545 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
22546 it will only be able to use the file-system utilities installed in the
22547 system profile. For example if you want to be able to mount NTFS
22548 file-systems in read and write fashion, you'll need to have
22549 @code{ntfs-3g} installed system-wide.
22552 @deffn {Scheme Variable} colord-service-type
22553 This is the type of the service that runs @command{colord}, a system
22554 service with a D-Bus
22555 interface to manage the color profiles of input and output devices such as
22556 screens and scanners. It is notably used by the GNOME Color Manager graphical
22557 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
22558 site} for more information.
22561 @cindex scanner access
22562 @defvr {Scheme Variable} sane-service-type
22563 This service provides access to scanners @i{via}
22564 @uref{http://www.sane-project.org, SANE} by installing the necessary
22565 udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
22566 Services}) and relies by default on @code{sane-backends-minimal} package
22567 (see below) for hardware support.
22570 @defvr {Scheme Variable} sane-backends-minimal
22571 The default package which the @code{sane-service-type} installs. It
22572 supports many recent scanners.
22575 @defvr {Scheme Variable} sane-backends
22576 This package includes support for all scanners that
22577 @code{sane-backends-minimal} supports, plus older Hewlett-Packard
22578 scanners supported by @code{hplip} package. In order to use this on
22579 a system which relies on @code{%desktop-services}, you may use
22580 @code{modify-services} (@pxref{Service Reference,
22581 @code{modify-services}}) as illustrated below:
22584 (use-modules (gnu))
22585 (use-service-modules
22588 (use-package-modules
22592 (define %my-desktop-services
22593 ;; List of desktop services that supports a broader range of scanners.
22594 (modify-services %desktop-services
22595 (sane-service-type _ => sane-backends)))
22599 (services %my-desktop-services))
22603 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
22604 Return a configuration allowing an application to access GeoClue
22605 location data. @var{name} is the Desktop ID of the application, without
22606 the @code{.desktop} part. If @var{allowed?} is true, the application
22607 will have access to location information by default. The boolean
22608 @var{system?} value indicates whether an application is a system component
22609 or not. Finally @var{users} is a list of UIDs of all users for which
22610 this application is allowed location info access. An empty users list
22611 means that all users are allowed.
22614 @defvr {Scheme Variable} %standard-geoclue-applications
22615 The standard list of well-known GeoClue application configurations,
22616 granting authority to the GNOME date-and-time utility to ask for the
22617 current location in order to set the time zone, and allowing the
22618 IceCat and Epiphany web browsers to request location information.
22619 IceCat and Epiphany both query the user before allowing a web page to
22620 know the user's location.
22623 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
22624 [#:whitelist '()] @
22625 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
22626 [#:submit-data? #f]
22627 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
22628 [#:submission-nick "geoclue"] @
22629 [#:applications %standard-geoclue-applications]
22630 Return a service that runs the GeoClue location service. This service
22631 provides a D-Bus interface to allow applications to request access to a
22632 user's physical location, and optionally to add information to online
22633 location databases. See
22634 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
22635 web site} for more information.
22638 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
22639 [@w{#:auto-enable? #f}]
22640 Return a service that runs the @command{bluetoothd} daemon, which
22641 manages all the Bluetooth devices and provides a number of D-Bus
22642 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
22643 powered automatically at boot, which can be useful when using a
22644 bluetooth keyboard or mouse.
22646 Users need to be in the @code{lp} group to access the D-Bus service.
22649 @deffn {Scheme Variable} bluetooth-service-type
22650 This is the type for the @uref{https://bluez.org/, Linux Bluetooth Protocol
22651 Stack} (BlueZ) system, which generates the @file{/etc/bluetooth/main.conf}
22652 configuration file. The value for this type is a @command{bluetooth-configuration}
22653 record as in this example:
22656 (service bluetooth-service-type)
22659 See below for details about @code{bluetooth-configuration}.
22662 @deftp {Data Type} bluetooth-configuration
22663 Data type representing the configuration for @code{bluetooth-service}.
22666 @item @code{bluez} (default: @code{bluez})
22667 @code{bluez} package to use.
22669 @item @code{name} (default: @code{"BlueZ"})
22670 Default adapter name.
22672 @item @code{class} (default: @code{#x000000})
22673 Default device class. Only the major and minor device class bits are considered.
22675 @item @code{discoverable-timeout} (default: @code{180})
22676 How long to stay in discoverable mode before going back to non-discoverable. The
22677 value is in seconds.
22679 @item @code{always-pairable?} (default: @code{#f})
22680 Always allow pairing even if there are no agents registered.
22682 @item @code{pairable-timeout} (default: @code{0})
22683 How long to stay in pairable mode before going back to non-discoverable. The
22684 value is in seconds.
22686 @item @code{device-id} (default: @code{#f})
22687 Use vendor id source (assigner), vendor, product and version information for
22688 DID profile support. The values are separated by ":" and @var{assigner}, @var{VID},
22689 @var{PID} and @var{version}.
22691 Possible values are:
22695 @code{#f} to disable it,
22698 @code{"assigner:1234:5678:abcd"}, where @var{assigner} is either @code{usb} (default)
22699 or @code{bluetooth}.
22703 @item @code{reverse-service-discovery?} (default: @code{#t})
22704 Do reverse service discovery for previously unknown devices that connect to
22705 us. For BR/EDR this option is really only needed for qualification since the
22706 BITE tester doesn't like us doing reverse SDP for some test cases, for LE
22707 this disables the GATT client functionally so it can be used in system which
22708 can only operate as peripheral.
22710 @item @code{name-resolving?} (default: @code{#t})
22711 Enable name resolving after inquiry. Set it to @code{#f} if you don't need
22712 remote devices name and want shorter discovery cycle.
22714 @item @code{debug-keys?} (default: @code{#f})
22715 Enable runtime persistency of debug link keys. Default is false which makes
22716 debug link keys valid only for the duration of the connection that they were
22719 @item @code{controller-mode} (default: @code{'dual})
22720 Restricts all controllers to the specified transport. @code{'dual} means both
22721 BR/EDR and LE are enabled (if supported by the hardware).
22723 Possible values are:
22737 @item @code{multi-profile} (default: @code{'off})
22738 Enables Multi Profile Specification support. This allows to specify if system
22739 supports only Multiple Profiles Single Device (MPSD) configuration or both
22740 Multiple Profiles Single Device (MPSD) and Multiple Profiles Multiple Devices
22741 (MPMD) configurations.
22743 Possible values are:
22757 @item @code{fast-connectable?} (default: @code{#f})
22758 Permanently enables the Fast Connectable setting for adapters that support
22759 it. When enabled other devices can connect faster to us, however the
22760 tradeoff is increased power consumptions. This feature will fully work only
22761 on kernel version 4.1 and newer.
22763 @item @code{privacy} (default: @code{'off})
22764 Default privacy settings.
22768 @code{'off}: Disable local privacy
22771 @code{'network/on}: A device will only accept advertising packets from peer
22772 devices that contain private addresses. It may not be compatible with some
22773 legacy devices since it requires the use of RPA(s) all the time
22776 @code{'device}: A device in device privacy mode is only concerned about the
22777 privacy of the device and will accept advertising packets from peer devices
22778 that contain their Identity Address as well as ones that contain a private
22779 address, even if the peer device has distributed its IRK in the past
22783 and additionally, if @var{controller-mode} is set to @code{'dual}:
22787 @code{'limited-network}: Apply Limited Discoverable Mode to advertising, which
22788 follows the same policy as to BR/EDR that publishes the identity address when
22789 discoverable, and Network Privacy Mode for scanning
22792 @code{'limited-device}: Apply Limited Discoverable Mode to advertising, which
22793 follows the same policy as to BR/EDR that publishes the identity address when
22794 discoverable, and Device Privacy Mode for scanning.
22798 @item @code{just-works-repairing} (default: @code{'never})
22799 Specify the policy to the JUST-WORKS repairing initiated by peer.
22814 @item @code{temporary-timeout} (default: @code{30})
22815 How long to keep temporary devices around. The value is in seconds. @code{0}
22816 disables the timer completely.
22818 @item @code{refresh-discovery?} (default: @code{#t})
22819 Enables the device to issue an SDP request to update known services when
22820 profile is connected.
22822 @item @code{experimental} (default: @code{#f})
22823 Enables experimental features and interfaces, alternatively a list of UUIDs
22836 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
22839 List of possible UUIDs:
22842 @code{d4992530-b9ec-469f-ab01-6c481c47da1c}: BlueZ Experimental Debug,
22845 @code{671b10b5-42c0-4696-9227-eb28d1b049d6}: BlueZ Experimental Simultaneous Central and Peripheral,
22848 @code{"15c0a148-c273-11ea-b3de-0242ac130004}: BlueZ Experimental LL privacy,
22851 @code{330859bc-7506-492d-9370-9a6f0614037f}: BlueZ Experimental Bluetooth Quality Report,
22854 @code{a6695ace-ee7f-4fb9-881a-5fac66c629af}: BlueZ Experimental Offload Codecs.
22857 @item @code{remote-name-request-retry-delay} (default: @code{300})
22858 The duration to avoid retrying to resolve a peer's name, if the previous
22861 @item @code{page-scan-type} (default: @code{#f})
22862 BR/EDR Page scan activity type.
22864 @item @code{page-scan-interval} (default: @code{#f})
22865 BR/EDR Page scan activity interval.
22867 @item @code{page-scan-window} (default: @code{#f})
22868 BR/EDR Page scan activity window.
22870 @item @code{inquiry-scan-type} (default: @code{#f})
22871 BR/EDR Inquiry scan activity type.
22873 @item @code{inquiry-scan-interval} (default: @code{#f})
22874 BR/EDR Inquiry scan activity interval.
22876 @item @code{inquiry-scan-window} (default: @code{#f})
22877 BR/EDR Inquiry scan activity window.
22879 @item @code{link-supervision-timeout} (default: @code{#f})
22880 BR/EDR Link supervision timeout.
22882 @item @code{page-timeout} (default: @code{#f})
22883 BR/EDR Page timeout.
22885 @item @code{min-sniff-interval} (default: @code{#f})
22886 BR/EDR minimum sniff interval.
22888 @item @code{max-sniff-interval} (default: @code{#f})
22889 BR/EDR maximum sniff interval.
22891 @item @code{min-advertisement-interval} (default: @code{#f})
22892 LE minimum advertisement interval (used for legacy advertisement only).
22894 @item @code{max-advertisement-interval} (default: @code{#f})
22895 LE maximum advertisement interval (used for legacy advertisement only).
22897 @item @code{multi-advertisement-rotation-interval} (default: @code{#f})
22898 LE multiple advertisement rotation interval.
22900 @item @code{scan-interval-auto-connect} (default: @code{#f})
22901 LE scanning interval used for passive scanning supporting auto connect.
22903 @item @code{scan-window-auto-connect} (default: @code{#f})
22904 LE scanning window used for passive scanning supporting auto connect.
22906 @item @code{scan-interval-suspend} (default: @code{#f})
22907 LE scanning interval used for active scanning supporting wake from suspend.
22909 @item @code{scan-window-suspend} (default: @code{#f})
22910 LE scanning window used for active scanning supporting wake from suspend.
22912 @item @code{scan-interval-discovery} (default: @code{#f})
22913 LE scanning interval used for active scanning supporting discovery.
22915 @item @code{scan-window-discovery} (default: @code{#f})
22916 LE scanning window used for active scanning supporting discovery.
22918 @item @code{scan-interval-adv-monitor} (default: @code{#f})
22919 LE scanning interval used for passive scanning supporting the advertisement monitor APIs.
22921 @item @code{scan-window-adv-monitor} (default: @code{#f})
22922 LE scanning window used for passive scanning supporting the advertisement monitor APIs.
22924 @item @code{scan-interval-connect} (default: @code{#f})
22925 LE scanning interval used for connection establishment.
22927 @item @code{scan-window-connect} (default: @code{#f})
22928 LE scanning window used for connection establishment.
22930 @item @code{min-connection-interval} (default: @code{#f})
22931 LE default minimum connection interval. This value is superseded by any specific
22932 value provided via the Load Connection Parameters interface.
22934 @item @code{max-connection-interval} (default: @code{#f})
22935 LE default maximum connection interval. This value is superseded by any specific
22936 value provided via the Load Connection Parameters interface.
22938 @item @code{connection-latency} (default: @code{#f})
22939 LE default connection latency. This value is superseded by any specific
22940 value provided via the Load Connection Parameters interface.
22942 @item @code{connection-supervision-timeout} (default: @code{#f})
22943 LE default connection supervision timeout. This value is superseded by any specific
22944 value provided via the Load Connection Parameters interface.
22946 @item @code{autoconnect-timeout} (default: @code{#f})
22947 LE default autoconnect timeout. This value is superseded by any specific
22948 value provided via the Load Connection Parameters interface.
22950 @item @code{adv-mon-allowlist-scan-duration} (default: @code{300})
22951 Allowlist scan duration during interleaving scan. Only used when scanning for ADV
22952 monitors. The units are msec.
22954 @item @code{adv-mon-no-filter-scan-duration} (default: @code{500})
22955 No filter scan duration during interleaving scan. Only used when scanning for ADV
22956 monitors. The units are msec.
22958 @item @code{enable-adv-mon-interleave-scan?} (default: @code{#t})
22959 Enable/Disable Advertisement Monitor interleave scan for power saving.
22961 @item @code{cache} (default: @code{'always})
22962 GATT attribute cache.
22964 Possible values are:
22967 @code{'always}: Always cache attributes even for devices not paired, this is
22968 recommended as it is best for interoperability, with more consistent
22969 reconnection times and enables proper tracking of notifications for all
22973 @code{'yes}: Only cache attributes of paired devices
22976 @code{'no}: Never cache attributes.
22979 @item @code{key-size} (default: @code{0})
22980 Minimum required Encryption Key Size for accessing secured characteristics.
22982 Possible values are:
22985 @code{0}: Don't care
22988 @code{7 <= N <= 16}
22991 @item @code{exchange-mtu} (default: @code{517})
22992 Exchange MTU size. Possible values are:
22996 @code{23 <= N <= 517}
22999 @item @code{att-channels} (default: @code{3})
23000 Number of ATT channels. Possible values are:
23004 @code{1}: Disables EATT
23010 @item @code{session-mode} (default: @code{'basic})
23011 AVDTP L2CAP signalling channel mode.
23013 Possible values are:
23017 @code{'basic}: Use L2CAP basic mode
23020 @code{'ertm}: Use L2CAP enhanced retransmission mode.
23023 @item @code{stream-mode} (default: @code{'basic})
23024 AVDTP L2CAP transport channel mode.
23026 Possible values are:
23030 @code{'basic}: Use L2CAP basic mode
23033 @code{'streaming}: Use L2CAP streaming mode.
23036 @item @code{reconnect-uuids} (default: @code{'()})
23037 The ReconnectUUIDs defines the set of remote services that should try
23038 to be reconnected to in case of a link loss (link supervision
23039 timeout). The policy plugin should contain a sane set of values by
23040 default, but this list can be overridden here. By setting the list to
23041 empty the reconnection feature gets disabled.
23050 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
23053 @item @code{reconnect-attempts} (default: @code{7})
23054 Defines the number of attempts to reconnect after a link lost. Setting
23055 the value to 0 disables reconnecting feature.
23057 @item @code{reconnect-intervals} (default: @code{'(1 2 4 8 16 32 64)})
23058 Defines a list of intervals in seconds to use in between attempts. If
23059 the number of attempts defined in @var{reconnect-attempts} is bigger than
23060 the list of intervals the last interval is repeated until the last attempt.
23062 @item @code{auto-enable?} (default: @code{#f})
23063 Defines option to enable all controllers when they are found. This includes
23064 adapters present on start as well as adapters that are plugged in later on.
23066 @item @code{resume-delay} (default: @code{2})
23067 Audio devices that were disconnected due to suspend will be reconnected on
23068 resume. @var{resume-delay} determines the delay between when the controller
23069 resumes from suspend and a connection attempt is made. A longer delay is
23070 better for better co-existence with Wi-Fi. The value is in seconds.
23072 @item @code{rssi-sampling-period} (default: @code{#xFF})
23073 Default RSSI Sampling Period. This is used when a client registers an
23074 advertisement monitor and leaves the RSSISamplingPeriod unset.
23076 Possible values are:
23079 @code{#x0}: Report all advertisements
23082 @code{N = #xXX}: Report advertisements every N x 100 msec (range: #x01 to #xFE)
23085 @code{#xFF}: Report only one advertisement per device during monitoring period.
23091 @defvr {Scheme Variable} gnome-keyring-service-type
23092 This is the type of the service that adds the
23093 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
23094 value is a @code{gnome-keyring-configuration} object (see below).
23096 This service adds the @code{gnome-keyring} package to the system profile
23097 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
23098 a user's login keyring when they log in or setting its password with passwd.
23101 @deftp {Data Type} gnome-keyring-configuration
23102 Configuration record for the GNOME Keyring service.
23105 @item @code{keyring} (default: @code{gnome-keyring})
23106 The GNOME keyring package to use.
23108 @item @code{pam-services}
23109 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
23110 services to extend, where @var{service} is the name of an existing
23111 service to extend and @var{kind} is one of @code{login} or
23114 If @code{login} is given, it adds an optional
23115 @code{pam_gnome_keyring.so} to the auth block without arguments and to
23116 the session block with @code{auto_start}. If @code{passwd} is given, it
23117 adds an optional @code{pam_gnome_keyring.so} to the password block
23120 By default, this field contains ``gdm-password'' with the value @code{login}
23121 and ``passwd'' is with the value @code{passwd}.
23125 @defvr {Scheme Variable} seatd-service-type
23126 @uref{https://sr.ht/~kennylevinsen/seatd/, seatd} is a minimal seat
23129 Seat management takes care of mediating access to shared devices (graphics,
23130 input), without requiring the applications needing access to be root.
23135 ;; make sure seatd is running
23136 (service seatd-service-type))
23138 ;; normally one would want %base-services
23144 @deftp {Data Type} seatd-configuration
23145 Configuration record for the seatd daemon service.
23148 @item @code{seatd} (default: @code{seatd})
23149 The seatd package to use.
23151 @item @code{user} (default: @samp{"root"})
23152 User to own the seatd socket.
23154 @item @code{group} (default: @samp{"users"})
23155 Group to own the seatd socket.
23157 @item @code{socket} (default: @samp{"/run/seatd.sock"})
23158 Where to create the seatd socket.
23160 @item @code{logfile} (default: @samp{"/var/log/seatd.log"})
23161 Log file to write to.
23163 @item @code{loglevel} (default: @samp{"error"})
23164 Log level to output logs. Possible values: @samp{"silent"}, @samp{"error"},
23165 @samp{"info"} and @samp{"debug"}.
23171 @node Sound Services
23172 @subsection Sound Services
23174 @cindex sound support
23176 @cindex PulseAudio, sound support
23178 The @code{(gnu services sound)} module provides a service to configure the
23179 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
23180 preferred ALSA output driver.
23182 @deffn {Scheme Variable} alsa-service-type
23183 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
23184 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
23185 configuration file. The value for this type is a @command{alsa-configuration}
23186 record as in this example:
23189 (service alsa-service-type)
23192 See below for details about @code{alsa-configuration}.
23195 @deftp {Data Type} alsa-configuration
23196 Data type representing the configuration for @code{alsa-service}.
23199 @item @code{alsa-plugins} (default: @var{alsa-plugins})
23200 @code{alsa-plugins} package to use.
23202 @item @code{pulseaudio?} (default: @var{#t})
23203 Whether ALSA applications should transparently be made to use the
23204 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
23206 Using PulseAudio allows you to run several sound-producing applications
23207 at the same time and to individual control them @i{via}
23208 @command{pavucontrol}, among other things.
23210 @item @code{extra-options} (default: @var{""})
23211 String to append to the @file{/etc/asound.conf} file.
23216 Individual users who want to override the system configuration of ALSA can do
23217 it with the @file{~/.asoundrc} file:
23220 # In guix, we have to specify the absolute path for plugins.
23222 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
23225 # Routing ALSA to jack:
23226 # <http://jackaudio.org/faq/routing_alsa.html>.
23230 0 system:playback_1
23231 1 system:playback_2
23248 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
23251 @deffn {Scheme Variable} pulseaudio-service-type
23252 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
23253 sound server. It exists to allow system overrides of the default settings
23254 via @code{pulseaudio-configuration}, see below.
23257 This service overrides per-user configuration files. If you want
23258 PulseAudio to honor configuration files in @file{~/.config/pulse} you
23259 have to unset the environment variables @env{PULSE_CONFIG} and
23260 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
23264 This service on its own does not ensure, that the @code{pulseaudio} package
23265 exists on your machine. It merely adds configuration files for it, as
23266 detailed below. In the (admittedly unlikely) case, that you find yourself
23267 without a @code{pulseaudio} package, consider enabling it through the
23268 @code{alsa-service-type} above.
23272 @deftp {Data Type} pulseaudio-configuration
23273 Data type representing the configuration for @code{pulseaudio-service}.
23276 @item @code{client-conf} (default: @code{'()})
23277 List of settings to set in @file{client.conf}.
23278 Accepts a list of strings or symbol-value pairs. A string will be
23279 inserted as-is with a newline added. A pair will be formatted as
23280 ``key = value'', again with a newline added.
23282 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
23283 List of settings to set in @file{daemon.conf}, formatted just like
23286 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
23287 Script file to use as @file{default.pa}. In case the
23288 @code{extra-script-files} field below is used, an @code{.include}
23289 directive pointing to @file{/etc/pulse/default.pa.d} is appended to the
23292 @item @code{extra-script-files} (default: @code{'())})
23293 A list of file-like objects defining extra PulseAudio scripts to run at
23294 the initialization of the @command{pulseaudio} daemon, after the main
23295 @code{script-file}. The scripts are deployed to the
23296 @file{/etc/pulse/default.pa.d} directory; they should have the
23297 @samp{.pa} file name extension. For a reference of the available
23298 commands, refer to @command{man pulse-cli-syntax}.
23300 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
23301 Script file to use as @file{system.pa}.
23304 The example below sets the default PulseAudio card profile, the default
23305 sink and the default source to use for a old SoundBlaster Audigy sound
23308 (pulseaudio-configuration
23309 (extra-script-files
23310 (list (plain-file "audigy.pa"
23312 set-card-profile alsa_card.pci-0000_01_01.0 \
23313 output:analog-surround-40+input:analog-mono
23314 set-default-source alsa_input.pci-0000_01_01.0.analog-mono
23315 set-default-sink alsa_output.pci-0000_01_01.0.analog-surround-40\n")))))
23318 Note that @code{pulseaudio-service-type} is part of
23319 @code{%desktop-services}; if your operating system declaration was
23320 derived from one of the desktop templates, you'll want to adjust the
23321 above example to modify the existing @code{pulseaudio-service-type} via
23322 @code{modify-services} (@pxref{Service Reference,
23323 @code{modify-services}}), instead of defining a new one.
23327 @deffn {Scheme Variable} ladspa-service-type
23328 This service sets the @var{LADSPA_PATH} variable, so that programs, which
23329 respect it, e.g. PulseAudio, can load LADSPA plugins.
23331 The following example will setup the service to enable modules from the
23332 @code{swh-plugins} package:
23335 (service ladspa-service-type
23336 (ladspa-configuration (plugins (list swh-plugins))))
23339 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
23344 @node Database Services
23345 @subsection Database Services
23349 The @code{(gnu services databases)} module provides the following services.
23351 @subsubheading PostgreSQL
23353 The following example describes a PostgreSQL service with the default
23357 (service postgresql-service-type
23358 (postgresql-configuration
23359 (postgresql postgresql-10)))
23362 If the services fails to start, it may be due to an incompatible
23363 cluster already present in @var{data-directory}. Adjust it (or, if you
23364 don't need the cluster anymore, delete @var{data-directory}), then
23365 restart the service.
23367 Peer authentication is used by default and the @code{postgres} user
23368 account has no shell, which prevents the direct execution of @code{psql}
23369 commands as this user. To use @code{psql}, you can temporarily log in
23370 as @code{postgres} using a shell, create a PostgreSQL superuser with the
23371 same name as one of the system users and then create the associated
23375 sudo -u postgres -s /bin/sh
23376 createuser --interactive
23377 createdb $MY_USER_LOGIN # Replace appropriately.
23380 @deftp {Data Type} postgresql-configuration
23381 Data type representing the configuration for the
23382 @code{postgresql-service-type}.
23385 @item @code{postgresql}
23386 PostgreSQL package to use for the service.
23388 @item @code{port} (default: @code{5432})
23389 Port on which PostgreSQL should listen.
23391 @item @code{locale} (default: @code{"en_US.utf8"})
23392 Locale to use as the default when creating the database cluster.
23394 @item @code{config-file} (default: @code{(postgresql-config-file)})
23395 The configuration file to use when running PostgreSQL@. The default
23396 behaviour uses the postgresql-config-file record with the default values
23399 @item @code{log-directory} (default: @code{"/var/log/postgresql"})
23400 The directory where @command{pg_ctl} output will be written in a file
23401 named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
23402 configuration errors for instance.
23404 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
23405 Directory in which to store the data.
23407 @item @code{extension-packages} (default: @code{'()})
23408 @cindex postgresql extension-packages
23409 Additional extensions are loaded from packages listed in
23410 @var{extension-packages}. Extensions are available at runtime. For instance,
23411 to create a geographic database using the @code{postgis} extension, a user can
23412 configure the postgresql-service as in this example:
23416 (use-package-modules databases geo)
23420 ;; postgresql is required to run `psql' but postgis is not required for
23421 ;; proper operation.
23422 (packages (cons* postgresql %base-packages))
23425 (service postgresql-service-type
23426 (postgresql-configuration
23427 (postgresql postgresql-10)
23428 (extension-packages (list postgis))))
23432 Then the extension becomes visible and you can initialise an empty geographic
23433 database in this way:
23437 > create database postgistest;
23438 > \connect postgistest;
23439 > create extension postgis;
23440 > create extension postgis_topology;
23443 There is no need to add this field for contrib extensions such as hstore or
23444 dblink as they are already loadable by postgresql. This field is only
23445 required to add extensions provided by other packages.
23450 @deftp {Data Type} postgresql-config-file
23451 Data type representing the PostgreSQL configuration file. As shown in
23452 the following example, this can be used to customize the configuration
23453 of PostgreSQL@. Note that you can use any G-expression or filename in
23454 place of this record, if you already have a configuration file you'd
23455 like to use for example.
23458 (service postgresql-service-type
23459 (postgresql-configuration
23461 (postgresql-config-file
23462 (log-destination "stderr")
23464 (plain-file "pg_hba.conf"
23466 local all all trust
23467 host all all 127.0.0.1/32 md5
23468 host all all ::1/128 md5"))
23470 '(("session_preload_libraries" "auto_explain")
23471 ("random_page_cost" 2)
23472 ("auto_explain.log_min_duration" "100 ms")
23473 ("work_mem" "500 MB")
23474 ("logging_collector" #t)
23475 ("log_directory" "/var/log/postgresql")))))))
23479 @item @code{log-destination} (default: @code{"syslog"})
23480 The logging method to use for PostgreSQL@. Multiple values are accepted,
23481 separated by commas.
23483 @item @code{hba-file} (default: @code{%default-postgres-hba})
23484 Filename or G-expression for the host-based authentication
23487 @item @code{ident-file} (default: @code{%default-postgres-ident})
23488 Filename or G-expression for the user name mapping configuration.
23490 @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
23491 Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
23492 is to listen for connections from client applications. If set to
23493 @code{""} PostgreSQL does not listen on any Unix-domain sockets, in
23494 which case only TCP/IP sockets can be used to connect to the server.
23496 By default, the @code{#false} value means the PostgreSQL default value
23497 will be used, which is currently @samp{/tmp}.
23499 @item @code{extra-config} (default: @code{'()})
23500 List of additional keys and values to include in the PostgreSQL config
23501 file. Each entry in the list should be a list where the first element
23502 is the key, and the remaining elements are the values.
23504 The values can be numbers, booleans or strings and will be mapped to
23505 PostgreSQL parameters types @code{Boolean}, @code{String},
23506 @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
23507 @uref{https://www.postgresql.org/docs/current/config-setting.html,
23513 @deffn {Scheme Variable} postgresql-role-service-type
23514 This service allows to create PostgreSQL roles and databases after
23515 PostgreSQL service start. Here is an example of its use.
23518 (service postgresql-role-service-type
23519 (postgresql-role-configuration
23521 (list (postgresql-role
23523 (create-database? #t))))))
23526 This service can be extended with extra roles, as in this
23530 (service-extension postgresql-role-service-type
23531 (const (postgresql-role
23533 (create-database? #t))))
23537 @deftp {Data Type} postgresql-role
23538 PostgreSQL manages database access permissions using the concept of
23539 roles. A role can be thought of as either a database user, or a group
23540 of database users, depending on how the role is set up. Roles can own
23541 database objects (for example, tables) and can assign privileges on
23542 those objects to other roles to control who has access to which objects.
23548 @item @code{permissions} (default: @code{'(createdb login)})
23549 The role permissions list. Supported permissions are @code{bypassrls},
23550 @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
23553 @item @code{create-database?} (default: @code{#f})
23554 Whether to create a database with the same name as the role.
23559 @deftp {Data Type} postgresql-role-configuration
23560 Data type representing the configuration of
23561 @var{postgresql-role-service-type}.
23564 @item @code{host} (default: @code{"/var/run/postgresql"})
23565 The PostgreSQL host to connect to.
23567 @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
23568 File name of the log file.
23570 @item @code{roles} (default: @code{'()})
23571 The initial PostgreSQL roles to create.
23575 @subsubheading MariaDB/MySQL
23577 @defvr {Scheme Variable} mysql-service-type
23578 This is the service type for a MySQL or MariaDB database server. Its value
23579 is a @code{mysql-configuration} object that specifies which package to use,
23580 as well as various settings for the @command{mysqld} daemon.
23583 @deftp {Data Type} mysql-configuration
23584 Data type representing the configuration of @var{mysql-service-type}.
23587 @item @code{mysql} (default: @var{mariadb})
23588 Package object of the MySQL database server, can be either @var{mariadb}
23591 For MySQL, a temporary root password will be displayed at activation time.
23592 For MariaDB, the root password is empty.
23594 @item @code{bind-address} (default: @code{"127.0.0.1"})
23595 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
23596 to bind to all available network interfaces.
23598 @item @code{port} (default: @code{3306})
23599 TCP port on which the database server listens for incoming connections.
23601 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
23602 Socket file to use for local (non-network) connections.
23604 @item @code{extra-content} (default: @code{""})
23605 Additional settings for the @file{my.cnf} configuration file.
23607 @item @code{extra-environment} (default: @code{#~'()})
23608 List of environment variables passed to the @command{mysqld} process.
23610 @item @code{auto-upgrade?} (default: @code{#t})
23611 Whether to automatically run @command{mysql_upgrade} after starting the
23612 service. This is necessary to upgrade the @dfn{system schema} after
23613 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
23614 be disabled if you would rather do that manually.
23619 @subsubheading Memcached
23621 @defvr {Scheme Variable} memcached-service-type
23622 This is the service type for the @uref{https://memcached.org/,
23623 Memcached} service, which provides a distributed in memory cache. The
23624 value for the service type is a @code{memcached-configuration} object.
23628 (service memcached-service-type)
23631 @deftp {Data Type} memcached-configuration
23632 Data type representing the configuration of memcached.
23635 @item @code{memcached} (default: @code{memcached})
23636 The Memcached package to use.
23638 @item @code{interfaces} (default: @code{'("0.0.0.0")})
23639 Network interfaces on which to listen.
23641 @item @code{tcp-port} (default: @code{11211})
23642 Port on which to accept connections.
23644 @item @code{udp-port} (default: @code{11211})
23645 Port on which to accept UDP connections on, a value of 0 will disable
23646 listening on a UDP socket.
23648 @item @code{additional-options} (default: @code{'()})
23649 Additional command line options to pass to @code{memcached}.
23653 @subsubheading Redis
23655 @defvr {Scheme Variable} redis-service-type
23656 This is the service type for the @uref{https://redis.io/, Redis}
23657 key/value store, whose value is a @code{redis-configuration} object.
23660 @deftp {Data Type} redis-configuration
23661 Data type representing the configuration of redis.
23664 @item @code{redis} (default: @code{redis})
23665 The Redis package to use.
23667 @item @code{bind} (default: @code{"127.0.0.1"})
23668 Network interface on which to listen.
23670 @item @code{port} (default: @code{6379})
23671 Port on which to accept connections on, a value of 0 will disable
23672 listening on a TCP socket.
23674 @item @code{working-directory} (default: @code{"/var/lib/redis"})
23675 Directory in which to store the database and related files.
23679 @node Mail Services
23680 @subsection Mail Services
23684 The @code{(gnu services mail)} module provides Guix service definitions
23685 for email services: IMAP, POP3, and LMTP servers, as well as mail
23686 transport agents (MTAs). Lots of acronyms! These services are detailed
23687 in the subsections below.
23689 @subsubheading Dovecot Service
23691 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
23692 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
23695 By default, Dovecot does not need much configuration; the default
23696 configuration object created by @code{(dovecot-configuration)} will
23697 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
23698 certificate will be generated for TLS-protected connections, though
23699 Dovecot will also listen on cleartext ports by default. There are a
23700 number of options, though, which mail administrators might need to change,
23701 and as is the case with other services, Guix allows the system
23702 administrator to specify these parameters via a uniform Scheme interface.
23704 For example, to specify that mail is located at @code{maildir~/.mail},
23705 one would instantiate the Dovecot service like this:
23708 (dovecot-service #:config
23709 (dovecot-configuration
23710 (mail-location "maildir:~/.mail")))
23713 The available configuration parameters follow. Each parameter
23714 definition is preceded by its type; for example, @samp{string-list foo}
23715 indicates that the @code{foo} parameter should be specified as a list of
23716 strings. There is also a way to specify the configuration as a string,
23717 if you have an old @code{dovecot.conf} file that you want to port over
23718 from some other system; see the end for more details.
23720 @c The following documentation was initially generated by
23721 @c (generate-documentation) in (gnu services mail). Manually maintained
23722 @c documentation is better, so we shouldn't hesitate to edit below as
23723 @c needed. However if the change you want to make to this documentation
23724 @c can be done in an automated way, it's probably easier to change
23725 @c (generate-documentation) than to make it below and have to deal with
23726 @c the churn as dovecot updates.
23728 Available @code{dovecot-configuration} fields are:
23730 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
23731 The dovecot package.
23734 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
23735 A list of IPs or hosts where to listen for connections. @samp{*}
23736 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
23737 interfaces. If you want to specify non-default ports or anything more
23738 complex, customize the address and port fields of the
23739 @samp{inet-listener} of the specific services you are interested in.
23742 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
23743 List of protocols we want to serve. Available protocols include
23744 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
23746 Available @code{protocol-configuration} fields are:
23748 @deftypevr {@code{protocol-configuration} parameter} string name
23749 The name of the protocol.
23752 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
23753 UNIX socket path to the master authentication server to find users.
23754 This is used by imap (for shared users) and lda.
23755 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
23758 @deftypevr {@code{protocol-configuration} parameter} boolean imap-metadata?
23759 Whether to enable the @code{IMAP METADATA} extension as defined in
23760 @uref{https://tools.ietf.org/html/rfc5464,RFC@tie{}5464}, which provides
23761 a means for clients to set and retrieve per-mailbox, per-user metadata
23762 and annotations over IMAP.
23764 If this is @samp{#t}, you must also specify a dictionary @i{via} the
23765 @code{mail-attribute-dict} setting.
23767 Defaults to @samp{#f}.
23771 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-notify-capabilities
23772 Which NOTIFY capabilities to report to clients that first connect to
23773 the ManageSieve service, before authentication. These may differ from the
23774 capabilities offered to authenticated users. If this field is left empty,
23775 report what the Sieve interpreter supports by default.
23777 Defaults to @samp{()}.
23780 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-sieve-capability
23781 Which SIEVE capabilities to report to clients that first connect to
23782 the ManageSieve service, before authentication. These may differ from the
23783 capabilities offered to authenticated users. If this field is left empty,
23784 report what the Sieve interpreter supports by default.
23786 Defaults to @samp{()}.
23790 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
23791 Space separated list of plugins to load.
23794 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
23795 Maximum number of IMAP connections allowed for a user from each IP
23796 address. NOTE: The username is compared case-sensitively.
23797 Defaults to @samp{10}.
23802 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
23803 List of services to enable. Available services include @samp{imap},
23804 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
23807 Available @code{service-configuration} fields are:
23809 @deftypevr {@code{service-configuration} parameter} string kind
23810 The service kind. Valid values include @code{director},
23811 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
23812 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
23813 @code{tcpwrap}, @code{quota-warning}, or anything else.
23816 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
23817 Listeners for the service. A listener is either a
23818 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
23819 an @code{inet-listener-configuration}.
23820 Defaults to @samp{()}.
23822 Available @code{unix-listener-configuration} fields are:
23824 @deftypevr {@code{unix-listener-configuration} parameter} string path
23825 Path to the file, relative to @code{base-dir} field. This is also used as
23829 @deftypevr {@code{unix-listener-configuration} parameter} string mode
23830 The access mode for the socket.
23831 Defaults to @samp{"0600"}.
23834 @deftypevr {@code{unix-listener-configuration} parameter} string user
23835 The user to own the socket.
23836 Defaults to @samp{""}.
23839 @deftypevr {@code{unix-listener-configuration} parameter} string group
23840 The group to own the socket.
23841 Defaults to @samp{""}.
23845 Available @code{fifo-listener-configuration} fields are:
23847 @deftypevr {@code{fifo-listener-configuration} parameter} string path
23848 Path to the file, relative to @code{base-dir} field. This is also used as
23852 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
23853 The access mode for the socket.
23854 Defaults to @samp{"0600"}.
23857 @deftypevr {@code{fifo-listener-configuration} parameter} string user
23858 The user to own the socket.
23859 Defaults to @samp{""}.
23862 @deftypevr {@code{fifo-listener-configuration} parameter} string group
23863 The group to own the socket.
23864 Defaults to @samp{""}.
23868 Available @code{inet-listener-configuration} fields are:
23870 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
23871 The protocol to listen for.
23874 @deftypevr {@code{inet-listener-configuration} parameter} string address
23875 The address on which to listen, or empty for all addresses.
23876 Defaults to @samp{""}.
23879 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
23880 The port on which to listen.
23883 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
23884 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
23886 Defaults to @samp{#t}.
23891 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
23892 Maximum number of simultaneous client connections per process. Once
23893 this number of connections is received, the next incoming connection
23894 will prompt Dovecot to spawn another process. If set to 0,
23895 @code{default-client-limit} is used instead.
23897 Defaults to @samp{0}.
23901 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
23902 Number of connections to handle before starting a new process.
23903 Typically the only useful values are 0 (unlimited) or 1. 1 is more
23904 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
23905 Defaults to @samp{1}.
23909 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
23910 Maximum number of processes that can exist for this service. If set to
23911 0, @code{default-process-limit} is used instead.
23913 Defaults to @samp{0}.
23917 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
23918 Number of processes to always keep waiting for more connections.
23919 Defaults to @samp{0}.
23922 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
23923 If you set @samp{service-count 0}, you probably need to grow
23925 Defaults to @samp{256000000}.
23930 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
23931 Dict configuration, as created by the @code{dict-configuration}
23934 Available @code{dict-configuration} fields are:
23936 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
23937 A list of key-value pairs that this dict should hold.
23938 Defaults to @samp{()}.
23943 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
23944 A list of passdb configurations, each one created by the
23945 @code{passdb-configuration} constructor.
23947 Available @code{passdb-configuration} fields are:
23949 @deftypevr {@code{passdb-configuration} parameter} string driver
23950 The driver that the passdb should use. Valid values include
23951 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
23953 Defaults to @samp{"pam"}.
23956 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
23957 Space separated list of arguments to the passdb driver.
23958 Defaults to @samp{""}.
23963 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
23964 List of userdb configurations, each one created by the
23965 @code{userdb-configuration} constructor.
23967 Available @code{userdb-configuration} fields are:
23969 @deftypevr {@code{userdb-configuration} parameter} string driver
23970 The driver that the userdb should use. Valid values include
23971 @samp{passwd} and @samp{static}.
23972 Defaults to @samp{"passwd"}.
23975 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
23976 Space separated list of arguments to the userdb driver.
23977 Defaults to @samp{""}.
23980 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
23981 Override fields from passwd.
23982 Defaults to @samp{()}.
23987 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
23988 Plug-in configuration, created by the @code{plugin-configuration}
23992 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
23993 List of namespaces. Each item in the list is created by the
23994 @code{namespace-configuration} constructor.
23996 Available @code{namespace-configuration} fields are:
23998 @deftypevr {@code{namespace-configuration} parameter} string name
23999 Name for this namespace.
24002 @deftypevr {@code{namespace-configuration} parameter} string type
24003 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
24004 Defaults to @samp{"private"}.
24007 @deftypevr {@code{namespace-configuration} parameter} string separator
24008 Hierarchy separator to use. You should use the same separator for
24009 all namespaces or some clients get confused. @samp{/} is usually a good
24010 one. The default however depends on the underlying mail storage
24012 Defaults to @samp{""}.
24015 @deftypevr {@code{namespace-configuration} parameter} string prefix
24016 Prefix required to access this namespace. This needs to be
24017 different for all namespaces. For example @samp{Public/}.
24018 Defaults to @samp{""}.
24021 @deftypevr {@code{namespace-configuration} parameter} string location
24022 Physical location of the mailbox. This is in the same format as
24023 mail_location, which is also the default for it.
24024 Defaults to @samp{""}.
24027 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
24028 There can be only one INBOX, and this setting defines which
24030 Defaults to @samp{#f}.
24033 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
24034 If namespace is hidden, it's not advertised to clients via NAMESPACE
24035 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
24036 useful when converting from another server with different namespaces
24037 which you want to deprecate but still keep working. For example you can
24038 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
24040 Defaults to @samp{#f}.
24043 @deftypevr {@code{namespace-configuration} parameter} boolean list?
24044 Show the mailboxes under this namespace with the LIST command. This
24045 makes the namespace visible for clients that do not support the NAMESPACE
24046 extension. The special @code{children} value lists child mailboxes, but
24047 hides the namespace prefix.
24048 Defaults to @samp{#t}.
24051 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
24052 Namespace handles its own subscriptions. If set to @code{#f}, the
24053 parent namespace handles them. The empty prefix should always have this
24055 Defaults to @samp{#t}.
24058 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
24059 List of predefined mailboxes in this namespace.
24060 Defaults to @samp{()}.
24062 Available @code{mailbox-configuration} fields are:
24064 @deftypevr {@code{mailbox-configuration} parameter} string name
24065 Name for this mailbox.
24068 @deftypevr {@code{mailbox-configuration} parameter} string auto
24069 @samp{create} will automatically create this mailbox.
24070 @samp{subscribe} will both create and subscribe to the mailbox.
24071 Defaults to @samp{"no"}.
24074 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
24075 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
24076 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
24077 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
24078 Defaults to @samp{()}.
24085 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
24086 Base directory where to store runtime data.
24087 Defaults to @samp{"/var/run/dovecot/"}.
24090 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
24091 Greeting message for clients.
24092 Defaults to @samp{"Dovecot ready."}.
24095 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
24096 List of trusted network ranges. Connections from these IPs are
24097 allowed to override their IP addresses and ports (for logging and for
24098 authentication checks). @samp{disable-plaintext-auth} is also ignored
24099 for these networks. Typically you would specify your IMAP proxy servers
24101 Defaults to @samp{()}.
24104 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
24105 List of login access check sockets (e.g.@: tcpwrap).
24106 Defaults to @samp{()}.
24109 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
24110 Show more verbose process titles (in ps). Currently shows user name
24111 and IP address. Useful for seeing who is actually using the IMAP
24112 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
24114 Defaults to @samp{#f}.
24117 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
24118 Should all processes be killed when Dovecot master process shuts down.
24119 Setting this to @code{#f} means that Dovecot can be upgraded without
24120 forcing existing client connections to close (although that could also
24121 be a problem if the upgrade is e.g.@: due to a security fix).
24122 Defaults to @samp{#t}.
24125 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
24126 If non-zero, run mail commands via this many connections to doveadm
24127 server, instead of running them directly in the same process.
24128 Defaults to @samp{0}.
24131 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
24132 UNIX socket or host:port used for connecting to doveadm server.
24133 Defaults to @samp{"doveadm-server"}.
24136 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
24137 List of environment variables that are preserved on Dovecot startup
24138 and passed down to all of its child processes. You can also give
24139 key=value pairs to always set specific settings.
24142 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
24143 Disable LOGIN command and all other plaintext authentications unless
24144 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
24145 matches the local IP (i.e.@: you're connecting from the same computer),
24146 the connection is considered secure and plaintext authentication is
24147 allowed. See also ssl=required setting.
24148 Defaults to @samp{#t}.
24151 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
24152 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
24153 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
24154 for caching to be used.
24155 Defaults to @samp{0}.
24158 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
24159 Time to live for cached data. After TTL expires the cached record
24160 is no longer used, *except* if the main database lookup returns internal
24161 failure. We also try to handle password changes automatically: If
24162 user's previous authentication was successful, but this one wasn't, the
24163 cache isn't used. For now this works only with plaintext
24165 Defaults to @samp{"1 hour"}.
24168 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
24169 TTL for negative hits (user not found, password mismatch).
24170 0 disables caching them completely.
24171 Defaults to @samp{"1 hour"}.
24174 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
24175 List of realms for SASL authentication mechanisms that need them.
24176 You can leave it empty if you don't want to support multiple realms.
24177 Many clients simply use the first one listed here, so keep the default
24179 Defaults to @samp{()}.
24182 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
24183 Default realm/domain to use if none was specified. This is used for
24184 both SASL realms and appending @@domain to username in plaintext
24186 Defaults to @samp{""}.
24189 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
24190 List of allowed characters in username. If the user-given username
24191 contains a character not listed in here, the login automatically fails.
24192 This is just an extra check to make sure user can't exploit any
24193 potential quote escaping vulnerabilities with SQL/LDAP databases. If
24194 you want to allow all characters, set this value to empty.
24195 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
24198 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
24199 Username character translations before it's looked up from
24200 databases. The value contains series of from -> to characters. For
24201 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
24202 translated to @samp{@@}.
24203 Defaults to @samp{""}.
24206 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
24207 Username formatting before it's looked up from databases. You can
24208 use the standard variables here, e.g.@: %Lu would lowercase the username,
24209 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
24210 change the @samp{@@} into @samp{-AT-}. This translation is done after
24211 @samp{auth-username-translation} changes.
24212 Defaults to @samp{"%Lu"}.
24215 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
24216 If you want to allow master users to log in by specifying the master
24217 username within the normal username string (i.e.@: not using SASL
24218 mechanism's support for it), you can specify the separator character
24219 here. The format is then <username><separator><master username>.
24220 UW-IMAP uses @samp{*} as the separator, so that could be a good
24222 Defaults to @samp{""}.
24225 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
24226 Username to use for users logging in with ANONYMOUS SASL
24228 Defaults to @samp{"anonymous"}.
24231 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
24232 Maximum number of dovecot-auth worker processes. They're used to
24233 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
24234 They're automatically created and destroyed as needed.
24235 Defaults to @samp{30}.
24238 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
24239 Host name to use in GSSAPI principal names. The default is to use
24240 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
24241 allow all keytab entries.
24242 Defaults to @samp{""}.
24245 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
24246 Kerberos keytab to use for the GSSAPI mechanism. Will use the
24247 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
24248 need to change the auth service to run as root to be able to read this
24250 Defaults to @samp{""}.
24253 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
24254 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
24255 and @samp{ntlm-auth} helper.
24256 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
24257 Defaults to @samp{#f}.
24260 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
24261 Path for Samba's @samp{ntlm-auth} helper binary.
24262 Defaults to @samp{"/usr/bin/ntlm_auth"}.
24265 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
24266 Time to delay before replying to failed authentications.
24267 Defaults to @samp{"2 secs"}.
24270 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
24271 Require a valid SSL client certificate or the authentication
24273 Defaults to @samp{#f}.
24276 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
24277 Take the username from client's SSL certificate, using
24278 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
24280 Defaults to @samp{#f}.
24283 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
24284 List of wanted authentication mechanisms. Supported mechanisms are:
24285 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
24286 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
24287 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
24288 @samp{disable-plaintext-auth} setting.
24291 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
24292 List of IPs or hostnames to all director servers, including ourself.
24293 Ports can be specified as ip:port. The default port is the same as what
24294 director service's @samp{inet-listener} is using.
24295 Defaults to @samp{()}.
24298 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
24299 List of IPs or hostnames to all backend mail servers. Ranges are
24300 allowed too, like 10.0.0.10-10.0.0.30.
24301 Defaults to @samp{()}.
24304 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
24305 How long to redirect users to a specific server after it no longer
24306 has any connections.
24307 Defaults to @samp{"15 min"}.
24310 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
24311 How the username is translated before being hashed. Useful values
24312 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
24313 are shared within domain.
24314 Defaults to @samp{"%Lu"}.
24317 @deftypevr {@code{dovecot-configuration} parameter} string log-path
24318 Log file to use for error messages. @samp{syslog} logs to syslog,
24319 @samp{/dev/stderr} logs to stderr.
24320 Defaults to @samp{"syslog"}.
24323 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
24324 Log file to use for informational messages. Defaults to
24326 Defaults to @samp{""}.
24329 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
24330 Log file to use for debug messages. Defaults to
24331 @samp{info-log-path}.
24332 Defaults to @samp{""}.
24335 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
24336 Syslog facility to use if you're logging to syslog. Usually if you
24337 don't want to use @samp{mail}, you'll use local0..local7. Also other
24338 standard facilities are supported.
24339 Defaults to @samp{"mail"}.
24342 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
24343 Log unsuccessful authentication attempts and the reasons why they
24345 Defaults to @samp{#f}.
24348 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
24349 In case of password mismatches, log the attempted password. Valid
24350 values are no, plain and sha1. sha1 can be useful for detecting brute
24351 force password attempts vs. user simply trying the same password over
24352 and over again. You can also truncate the value to n chars by appending
24353 ":n" (e.g.@: sha1:6).
24354 Defaults to @samp{"no"}.
24357 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
24358 Even more verbose logging for debugging purposes. Shows for example
24360 Defaults to @samp{#f}.
24363 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
24364 In case of password mismatches, log the passwords and used scheme so
24365 the problem can be debugged. Enabling this also enables
24367 Defaults to @samp{#f}.
24370 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
24371 Enable mail process debugging. This can help you figure out why
24372 Dovecot isn't finding your mails.
24373 Defaults to @samp{#f}.
24376 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
24377 Show protocol level SSL errors.
24378 Defaults to @samp{#f}.
24381 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
24382 Prefix for each line written to log file. % codes are in
24383 strftime(3) format.
24384 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
24387 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
24388 List of elements we want to log. The elements which have a
24389 non-empty variable value are joined together to form a comma-separated
24393 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
24394 Login log format. %s contains @samp{login-log-format-elements}
24395 string, %$ contains the data we want to log.
24396 Defaults to @samp{"%$: %s"}.
24399 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
24400 Log prefix for mail processes. See doc/wiki/Variables.txt for list
24401 of possible variables you can use.
24402 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
24405 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
24406 Format to use for logging mail deliveries. You can use variables:
24409 Delivery status message (e.g.@: @samp{saved to INBOX})
24421 Defaults to @samp{"msgid=%m: %$"}.
24424 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
24425 Location for users' mailboxes. The default is empty, which means
24426 that Dovecot tries to find the mailboxes automatically. This won't work
24427 if the user doesn't yet have any mail, so you should explicitly tell
24428 Dovecot the full location.
24430 If you're using mbox, giving a path to the INBOX
24431 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
24432 where the other mailboxes are kept. This is called the @emph{root mail
24433 directory}, and it must be the first path given in the
24434 @samp{mail-location} setting.
24436 There are a few special variables you can use, e.g.:
24442 user part in user@@domain, same as %u if there's no domain
24444 domain part in user@@domain, empty if there's no domain
24449 See doc/wiki/Variables.txt for full list. Some examples:
24451 @item maildir:~/Maildir
24452 @item mbox:~/mail:INBOX=/var/mail/%u
24453 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
24455 Defaults to @samp{""}.
24458 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
24459 System user and group used to access mails. If you use multiple,
24460 userdb can override these by returning uid or gid fields. You can use
24461 either numbers or names. <doc/wiki/UserIds.txt>.
24462 Defaults to @samp{""}.
24465 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
24467 Defaults to @samp{""}.
24470 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
24471 Group to enable temporarily for privileged operations. Currently
24472 this is used only with INBOX when either its initial creation or
24473 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
24475 Defaults to @samp{""}.
24478 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
24479 Grant access to these supplementary groups for mail processes.
24480 Typically these are used to set up access to shared mailboxes. Note
24481 that it may be dangerous to set these if users can create symlinks
24482 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
24483 could allow a user to delete others' mailboxes, or @code{ln -s
24484 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
24488 @deftypevr {@code{dovecot-configuration} parameter} string mail-attribute-dict
24489 The location of a dictionary used to store @code{IMAP METADATA}
24490 as defined by @uref{https://tools.ietf.org/html/rfc5464, RFC@tie{}5464}.
24492 The IMAP METADATA commands are available only if the ``imap''
24493 protocol configuration's @code{imap-metadata?} field is @samp{#t}.
24495 Defaults to @samp{""}.
24499 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
24500 Allow full file system access to clients. There's no access checks
24501 other than what the operating system does for the active UID/GID@. It
24502 works with both maildir and mboxes, allowing you to prefix mailboxes
24503 names with e.g.@: @file{/path/} or @file{~user/}.
24504 Defaults to @samp{#f}.
24507 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
24508 Don't use @code{mmap()} at all. This is required if you store indexes to
24509 shared file systems (NFS or clustered file system).
24510 Defaults to @samp{#f}.
24513 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
24514 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
24515 supports @samp{O_EXCL} since version 3, so this should be safe to use
24516 nowadays by default.
24517 Defaults to @samp{#t}.
24520 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
24521 When to use fsync() or fdatasync() calls:
24524 Whenever necessary to avoid losing important data
24526 Useful with e.g.@: NFS when @code{write()}s are delayed
24528 Never use it (best performance, but crashes can lose data).
24530 Defaults to @samp{"optimized"}.
24533 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
24534 Mail storage exists in NFS@. Set this to yes to make Dovecot flush
24535 NFS caches whenever needed. If you're using only a single mail server
24537 Defaults to @samp{#f}.
24540 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
24541 Mail index files also exist in NFS@. Setting this to yes requires
24542 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
24543 Defaults to @samp{#f}.
24546 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
24547 Locking method for index files. Alternatives are fcntl, flock and
24548 dotlock. Dotlocking uses some tricks which may create more disk I/O
24549 than other locking methods. NFS users: flock doesn't work, remember to
24550 change @samp{mmap-disable}.
24551 Defaults to @samp{"fcntl"}.
24554 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
24555 Directory in which LDA/LMTP temporarily stores incoming mails >128
24557 Defaults to @samp{"/tmp"}.
24560 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
24561 Valid UID range for users. This is mostly to make sure that users can't
24562 log in as daemons or other system users. Note that denying root logins is
24563 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
24565 Defaults to @samp{500}.
24568 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
24570 Defaults to @samp{0}.
24573 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
24574 Valid GID range for users. Users having non-valid GID as primary group ID
24575 aren't allowed to log in. If user belongs to supplementary groups with
24576 non-valid GIDs, those groups are not set.
24577 Defaults to @samp{1}.
24580 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
24582 Defaults to @samp{0}.
24585 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
24586 Maximum allowed length for mail keyword name. It's only forced when
24587 trying to create new keywords.
24588 Defaults to @samp{50}.
24591 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
24592 List of directories under which chrooting is allowed for mail
24593 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
24594 too). This setting doesn't affect @samp{login-chroot}
24595 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
24596 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
24597 which local users can modify, that may lead to root exploit. Usually
24598 this should be done only if you don't allow shell access for users.
24599 <doc/wiki/Chrooting.txt>.
24600 Defaults to @samp{()}.
24603 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
24604 Default chroot directory for mail processes. This can be overridden
24605 for specific users in user database by giving @samp{/./} in user's home
24606 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
24607 there is no real need to do chrooting, Dovecot doesn't allow users to
24608 access files outside their mail directory anyway. If your home
24609 directories are prefixed with the chroot directory, append @samp{/.} to
24610 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
24611 Defaults to @samp{""}.
24614 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
24615 UNIX socket path to master authentication server to find users.
24616 This is used by imap (for shared users) and lda.
24617 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
24620 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
24621 Directory where to look up mail plugins.
24622 Defaults to @samp{"/usr/lib/dovecot"}.
24625 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
24626 List of plugins to load for all services. Plugins specific to IMAP,
24627 LDA, etc.@: are added to this list in their own .conf files.
24628 Defaults to @samp{()}.
24631 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
24632 The minimum number of mails in a mailbox before updates are done to
24633 cache file. This allows optimizing Dovecot's behavior to do less disk
24634 writes at the cost of more disk reads.
24635 Defaults to @samp{0}.
24638 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
24639 When IDLE command is running, mailbox is checked once in a while to
24640 see if there are any new mails or other changes. This setting defines
24641 the minimum time to wait between those checks. Dovecot can also use
24642 dnotify, inotify and kqueue to find out immediately when changes
24644 Defaults to @samp{"30 secs"}.
24647 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
24648 Save mails with CR+LF instead of plain LF@. This makes sending those
24649 mails take less CPU, especially with sendfile() syscall with Linux and
24650 FreeBSD@. But it also creates a bit more disk I/O which may just make it
24651 slower. Also note that if other software reads the mboxes/maildirs,
24652 they may handle the extra CRs wrong and cause problems.
24653 Defaults to @samp{#f}.
24656 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
24657 By default LIST command returns all entries in maildir beginning
24658 with a dot. Enabling this option makes Dovecot return only entries
24659 which are directories. This is done by stat()ing each entry, so it
24660 causes more disk I/O.
24661 (For systems setting struct @samp{dirent->d_type} this check is free
24662 and it's done always regardless of this setting).
24663 Defaults to @samp{#f}.
24666 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
24667 When copying a message, do it with hard links whenever possible.
24668 This makes the performance much better, and it's unlikely to have any
24670 Defaults to @samp{#t}.
24673 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
24674 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
24675 directory only when its mtime changes unexpectedly or when we can't find
24676 the mail otherwise.
24677 Defaults to @samp{#f}.
24680 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
24681 Which locking methods to use for locking mbox. There are four
24686 Create <mailbox>.lock file. This is the oldest and most NFS-safe
24687 solution. If you want to use /var/mail/ like directory, the users will
24688 need write access to that directory.
24690 Same as dotlock, but if it fails because of permissions or because there
24691 isn't enough disk space, just skip it.
24693 Use this if possible. Works with NFS too if lockd is used.
24695 May not exist in all systems. Doesn't work with NFS.
24697 May not exist in all systems. Doesn't work with NFS.
24700 You can use multiple locking methods; if you do the order they're declared
24701 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
24702 locking methods as well. Some operating systems don't allow using some of
24703 them simultaneously.
24706 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
24710 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
24711 Maximum time to wait for lock (all of them) before aborting.
24712 Defaults to @samp{"5 mins"}.
24715 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
24716 If dotlock exists but the mailbox isn't modified in any way,
24717 override the lock file after this much time.
24718 Defaults to @samp{"2 mins"}.
24721 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
24722 When mbox changes unexpectedly we have to fully read it to find out
24723 what changed. If the mbox is large this can take a long time. Since
24724 the change is usually just a newly appended mail, it'd be faster to
24725 simply read the new mails. If this setting is enabled, Dovecot does
24726 this but still safely fallbacks to re-reading the whole mbox file
24727 whenever something in mbox isn't how it's expected to be. The only real
24728 downside to this setting is that if some other MUA changes message
24729 flags, Dovecot doesn't notice it immediately. Note that a full sync is
24730 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
24731 Defaults to @samp{#t}.
24734 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
24735 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
24736 EXAMINE, EXPUNGE or CHECK commands. If this is set,
24737 @samp{mbox-dirty-syncs} is ignored.
24738 Defaults to @samp{#f}.
24741 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
24742 Delay writing mbox headers until doing a full write sync (EXPUNGE
24743 and CHECK commands and when closing the mailbox). This is especially
24744 useful for POP3 where clients often delete all mails. The downside is
24745 that our changes aren't immediately visible to other MUAs.
24746 Defaults to @samp{#t}.
24749 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
24750 If mbox size is smaller than this (e.g.@: 100k), don't write index
24751 files. If an index file already exists it's still read, just not
24753 Defaults to @samp{0}.
24756 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
24757 Maximum dbox file size until it's rotated.
24758 Defaults to @samp{10000000}.
24761 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
24762 Maximum dbox file age until it's rotated. Typically in days. Day
24763 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
24765 Defaults to @samp{"1d"}.
24768 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
24769 When creating new mdbox files, immediately preallocate their size to
24770 @samp{mdbox-rotate-size}. This setting currently works only in Linux
24771 with some file systems (ext4, xfs).
24772 Defaults to @samp{#f}.
24775 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
24776 sdbox and mdbox support saving mail attachments to external files,
24777 which also allows single instance storage for them. Other backends
24778 don't support this for now.
24780 WARNING: This feature hasn't been tested much yet. Use at your own risk.
24782 Directory root where to store mail attachments. Disabled, if empty.
24783 Defaults to @samp{""}.
24786 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
24787 Attachments smaller than this aren't saved externally. It's also
24788 possible to write a plugin to disable saving specific attachments
24790 Defaults to @samp{128000}.
24793 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
24794 File system backend to use for saving attachments:
24797 No SiS done by Dovecot (but this might help FS's own deduplication)
24799 SiS with immediate byte-by-byte comparison during saving
24800 @item sis-queue posix
24801 SiS with delayed comparison and deduplication.
24803 Defaults to @samp{"sis posix"}.
24806 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
24807 Hash format to use in attachment filenames. You can add any text and
24808 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
24809 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
24810 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
24811 Defaults to @samp{"%@{sha1@}"}.
24814 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
24816 Defaults to @samp{100}.
24819 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
24821 Defaults to @samp{1000}.
24824 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
24825 Default VSZ (virtual memory size) limit for service processes.
24826 This is mainly intended to catch and kill processes that leak memory
24827 before they eat up everything.
24828 Defaults to @samp{256000000}.
24831 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
24832 Login user is internally used by login processes. This is the most
24833 untrusted user in Dovecot system. It shouldn't have access to anything
24835 Defaults to @samp{"dovenull"}.
24838 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
24839 Internal user is used by unprivileged processes. It should be
24840 separate from login user, so that login processes can't disturb other
24842 Defaults to @samp{"dovecot"}.
24845 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
24846 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
24847 Defaults to @samp{"required"}.
24850 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
24851 PEM encoded X.509 SSL/TLS certificate (public key).
24852 Defaults to @samp{"</etc/dovecot/default.pem"}.
24855 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
24856 PEM encoded SSL/TLS private key. The key is opened before
24857 dropping root privileges, so keep the key file unreadable by anyone but
24859 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
24862 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
24863 If key file is password protected, give the password here.
24864 Alternatively give it when starting dovecot with -p parameter. Since
24865 this file is often world-readable, you may want to place this setting
24866 instead to a different.
24867 Defaults to @samp{""}.
24870 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
24871 PEM encoded trusted certificate authority. Set this only if you
24872 intend to use @samp{ssl-verify-client-cert? #t}. The file should
24873 contain the CA certificate(s) followed by the matching
24874 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
24875 Defaults to @samp{""}.
24878 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
24879 Require that CRL check succeeds for client certificates.
24880 Defaults to @samp{#t}.
24883 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
24884 Request client to send a certificate. If you also want to require
24885 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
24886 Defaults to @samp{#f}.
24889 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
24890 Which field from certificate to use for username. commonName and
24891 x500UniqueIdentifier are the usual choices. You'll also need to set
24892 @samp{auth-ssl-username-from-cert? #t}.
24893 Defaults to @samp{"commonName"}.
24896 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
24897 Minimum SSL protocol version to accept.
24898 Defaults to @samp{"TLSv1"}.
24901 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
24902 SSL ciphers to use.
24903 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
24906 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
24907 SSL crypto device to use, for valid values run "openssl engine".
24908 Defaults to @samp{""}.
24911 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
24912 Address to use when sending rejection mails.
24913 %d expands to recipient domain.
24914 Defaults to @samp{"postmaster@@%d"}.
24917 @deftypevr {@code{dovecot-configuration} parameter} string hostname
24918 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
24919 and in LMTP replies. Default is the system's real hostname@@domain.
24920 Defaults to @samp{""}.
24923 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
24924 If user is over quota, return with temporary failure instead of
24926 Defaults to @samp{#f}.
24929 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
24930 Binary to use for sending mails.
24931 Defaults to @samp{"/usr/sbin/sendmail"}.
24934 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
24935 If non-empty, send mails via this SMTP host[:port] instead of
24937 Defaults to @samp{""}.
24940 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
24941 Subject: header to use for rejection mails. You can use the same
24942 variables as for @samp{rejection-reason} below.
24943 Defaults to @samp{"Rejected: %s"}.
24946 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
24947 Human readable error message for rejection mails. You can use
24960 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
24963 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
24964 Delimiter character between local-part and detail in email
24966 Defaults to @samp{"+"}.
24969 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
24970 Header where the original recipient address (SMTP's RCPT TO:
24971 address) is taken from if not available elsewhere. With dovecot-lda -a
24972 parameter overrides this. A commonly used header for this is
24974 Defaults to @samp{""}.
24977 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
24978 Should saving a mail to a nonexistent mailbox automatically create
24980 Defaults to @samp{#f}.
24983 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
24984 Should automatically created mailboxes be also automatically
24986 Defaults to @samp{#f}.
24989 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
24990 Maximum IMAP command line length. Some clients generate very long
24991 command lines with huge mailboxes, so you may need to raise this if you
24992 get "Too long argument" or "IMAP command line too large" errors
24994 Defaults to @samp{64000}.
24997 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
24998 IMAP logout format string:
25001 total number of bytes read from client
25003 total number of bytes sent to client.
25005 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
25006 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@}"}.
25009 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
25010 Override the IMAP CAPABILITY response. If the value begins with '+',
25011 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
25012 Defaults to @samp{""}.
25015 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
25016 How long to wait between "OK Still here" notifications when client
25018 Defaults to @samp{"2 mins"}.
25021 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
25022 ID field names and values to send to clients. Using * as the value
25023 makes Dovecot use the default value. The following fields have default
25024 values currently: name, version, os, os-version, support-url,
25026 Defaults to @samp{""}.
25029 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
25030 ID fields sent by client to log. * means everything.
25031 Defaults to @samp{""}.
25034 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
25035 Workarounds for various client bugs:
25038 @item delay-newmail
25039 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
25040 CHECK commands. Some clients ignore them otherwise, for example OSX
25041 Mail (<v2.1). Outlook Express breaks more badly though, without this it
25042 may show user "Message no longer in server" errors. Note that OE6
25043 still breaks even with this workaround if synchronization is set to
25046 @item tb-extra-mailbox-sep
25047 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
25048 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
25049 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
25051 @item tb-lsub-flags
25052 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
25053 This makes Thunderbird realize they aren't selectable and show them
25054 greyed out, instead of only later giving "not selectable" popup error.
25056 Defaults to @samp{()}.
25059 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
25060 Host allowed in URLAUTH URLs sent by client. "*" allows all.
25061 Defaults to @samp{""}.
25065 Whew! Lots of configuration options. The nice thing about it though is
25066 that Guix has a complete interface to Dovecot's configuration
25067 language. This allows not only a nice way to declare configurations,
25068 but also offers reflective capabilities as well: users can write code to
25069 inspect and transform configurations from within Scheme.
25071 However, it could be that you just want to get a @code{dovecot.conf} up
25072 and running. In that case, you can pass an
25073 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
25074 @code{dovecot-service}. As its name indicates, an opaque configuration
25075 does not have easy reflective capabilities.
25077 Available @code{opaque-dovecot-configuration} fields are:
25079 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
25080 The dovecot package.
25083 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
25084 The contents of the @code{dovecot.conf}, as a string.
25087 For example, if your @code{dovecot.conf} is just the empty string, you
25088 could instantiate a dovecot service like this:
25091 (dovecot-service #:config
25092 (opaque-dovecot-configuration
25096 @subsubheading OpenSMTPD Service
25098 @deffn {Scheme Variable} opensmtpd-service-type
25099 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
25100 service, whose value should be an @code{opensmtpd-configuration} object
25101 as in this example:
25104 (service opensmtpd-service-type
25105 (opensmtpd-configuration
25106 (config-file (local-file "./my-smtpd.conf"))))
25110 @deftp {Data Type} opensmtpd-configuration
25111 Data type representing the configuration of opensmtpd.
25114 @item @code{package} (default: @var{opensmtpd})
25115 Package object of the OpenSMTPD SMTP server.
25117 @item @code{config-file} (default: @code{%default-opensmtpd-config-file})
25118 File-like object of the OpenSMTPD configuration file to use. By default
25119 it listens on the loopback network interface, and allows for mail from
25120 users and daemons on the local machine, as well as permitting email to
25121 remote servers. Run @command{man smtpd.conf} for more information.
25123 @item @code{setgid-commands?} (default: @code{#t})
25124 Make the following commands setgid to @code{smtpq} so they can be
25125 executed: @command{smtpctl}, @command{sendmail}, @command{send-mail},
25126 @command{makemap}, @command{mailq}, and @command{newaliases}.
25127 @xref{Setuid Programs}, for more information on setgid programs.
25131 @subsubheading Exim Service
25133 @cindex mail transfer agent (MTA)
25134 @cindex MTA (mail transfer agent)
25137 @deffn {Scheme Variable} exim-service-type
25138 This is the type of the @uref{https://exim.org, Exim} mail transfer
25139 agent (MTA), whose value should be an @code{exim-configuration} object
25140 as in this example:
25143 (service exim-service-type
25144 (exim-configuration
25145 (config-file (local-file "./my-exim.conf"))))
25149 In order to use an @code{exim-service-type} service you must also have a
25150 @code{mail-aliases-service-type} service present in your
25151 @code{operating-system} (even if it has no aliases).
25153 @deftp {Data Type} exim-configuration
25154 Data type representing the configuration of exim.
25157 @item @code{package} (default: @var{exim})
25158 Package object of the Exim server.
25160 @item @code{config-file} (default: @code{#f})
25161 File-like object of the Exim configuration file to use. If its value is
25162 @code{#f} then use the default configuration file from the package
25163 provided in @code{package}. The resulting configuration file is loaded
25164 after setting the @code{exim_user} and @code{exim_group} configuration
25170 @subsubheading Getmail service
25175 @deffn {Scheme Variable} getmail-service-type
25176 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
25177 mail retriever, whose value should be an @code{getmail-configuration}.
25180 Available @code{getmail-configuration} fields are:
25182 @deftypevr {@code{getmail-configuration} parameter} symbol name
25183 A symbol to identify the getmail service.
25185 Defaults to @samp{"unset"}.
25189 @deftypevr {@code{getmail-configuration} parameter} package package
25190 The getmail package to use.
25194 @deftypevr {@code{getmail-configuration} parameter} string user
25195 The user to run getmail as.
25197 Defaults to @samp{"getmail"}.
25201 @deftypevr {@code{getmail-configuration} parameter} string group
25202 The group to run getmail as.
25204 Defaults to @samp{"getmail"}.
25208 @deftypevr {@code{getmail-configuration} parameter} string directory
25209 The getmail directory to use.
25211 Defaults to @samp{"/var/lib/getmail/default"}.
25215 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
25216 The getmail configuration file to use.
25218 Available @code{getmail-configuration-file} fields are:
25220 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
25221 What mail account to retrieve mail from, and how to access that account.
25223 Available @code{getmail-retriever-configuration} fields are:
25225 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
25226 The type of mail retriever to use. Valid values include @samp{passwd}
25229 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
25233 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
25234 Username to login to the mail server with.
25236 Defaults to @samp{unset}.
25240 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
25241 Username to login to the mail server with.
25243 Defaults to @samp{unset}.
25247 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
25248 Port number to connect to.
25250 Defaults to @samp{#f}.
25254 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
25255 Override fields from passwd.
25257 Defaults to @samp{""}.
25261 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
25262 Override fields from passwd.
25264 Defaults to @samp{()}.
25268 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
25269 PEM-formatted key file to use for the TLS negotiation.
25271 Defaults to @samp{""}.
25275 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
25276 PEM-formatted certificate file to use for the TLS negotiation.
25278 Defaults to @samp{""}.
25282 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
25283 CA certificates to use.
25285 Defaults to @samp{""}.
25289 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
25290 Extra retriever parameters.
25292 Defaults to @samp{()}.
25298 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
25299 What to do with retrieved messages.
25301 Available @code{getmail-destination-configuration} fields are:
25303 @deftypevr {@code{getmail-destination-configuration} parameter} string type
25304 The type of mail destination. Valid values include @samp{Maildir},
25305 @samp{Mboxrd} and @samp{MDA_external}.
25307 Defaults to @samp{unset}.
25311 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
25312 The path option for the mail destination. The behaviour depends on the
25315 Defaults to @samp{""}.
25319 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
25320 Extra destination parameters
25322 Defaults to @samp{()}.
25328 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
25331 Available @code{getmail-options-configuration} fields are:
25333 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
25334 If set to @samp{0}, getmail will only print warnings and errors. A
25335 value of @samp{1} means that messages will be printed about retrieving
25336 and deleting messages. If set to @samp{2}, getmail will print messages
25337 about each of its actions.
25339 Defaults to @samp{1}.
25343 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
25344 If true, getmail will retrieve all available messages. Otherwise it
25345 will only retrieve messages it hasn't seen previously.
25347 Defaults to @samp{#t}.
25351 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
25352 If set to true, messages will be deleted from the server after
25353 retrieving and successfully delivering them. Otherwise, messages will
25354 be left on the server.
25356 Defaults to @samp{#f}.
25360 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
25361 Getmail will delete messages this number of days after seeing them, if
25362 they have been delivered. This means messages will be left on the
25363 server this number of days after delivering them. A value of @samp{0}
25364 disabled this feature.
25366 Defaults to @samp{0}.
25370 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
25371 Delete messages larger than this of bytes after retrieving them, even if
25372 the delete and delete-after options are disabled. A value of @samp{0}
25373 disables this feature.
25375 Defaults to @samp{0}.
25379 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
25380 Retrieve messages totalling up to this number of bytes before closing
25381 the session with the server. A value of @samp{0} disables this feature.
25383 Defaults to @samp{0}.
25387 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
25388 Don't retrieve messages larger than this number of bytes. A value of
25389 @samp{0} disables this feature.
25391 Defaults to @samp{0}.
25395 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
25396 If true, getmail will add a Delivered-To header to messages.
25398 Defaults to @samp{#t}.
25402 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
25403 If set, getmail adds a Received header to the messages.
25405 Defaults to @samp{#t}.
25409 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
25410 Getmail will record a log of its actions to the named file. A value of
25411 @samp{""} disables this feature.
25413 Defaults to @samp{""}.
25417 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
25418 If true, getmail will record a log of its actions using the system
25421 Defaults to @samp{#f}.
25425 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
25426 If true, getmail will log information about messages not retrieved and
25427 the reason for not retrieving them, as well as starting and ending
25430 Defaults to @samp{#f}.
25434 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
25435 Extra options to include.
25437 Defaults to @samp{()}.
25445 @deftypevr {@code{getmail-configuration} parameter} list idle
25446 A list of mailboxes that getmail should wait on the server for new mail
25447 notifications. This depends on the server supporting the IDLE
25450 Defaults to @samp{()}.
25454 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
25455 Environment variables to set for getmail.
25457 Defaults to @samp{()}.
25461 @subsubheading Mail Aliases Service
25463 @cindex email aliases
25464 @cindex aliases, for email addresses
25466 @deffn {Scheme Variable} mail-aliases-service-type
25467 This is the type of the service which provides @code{/etc/aliases},
25468 specifying how to deliver mail to users on this system.
25471 (service mail-aliases-service-type
25472 '(("postmaster" "bob")
25473 ("bob" "bob@@example.com" "bob@@example2.com")))
25477 The configuration for a @code{mail-aliases-service-type} service is an
25478 association list denoting how to deliver mail that comes to this
25479 system. Each entry is of the form @code{(alias addresses ...)}, with
25480 @code{alias} specifying the local alias and @code{addresses} specifying
25481 where to deliver this user's mail.
25483 The aliases aren't required to exist as users on the local system. In
25484 the above example, there doesn't need to be a @code{postmaster} entry in
25485 the @code{operating-system}'s @code{user-accounts} in order to deliver
25486 the @code{postmaster} mail to @code{bob} (which subsequently would
25487 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
25489 @subsubheading GNU Mailutils IMAP4 Daemon
25490 @cindex GNU Mailutils IMAP4 Daemon
25492 @deffn {Scheme Variable} imap4d-service-type
25493 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
25494 mailutils, GNU Mailutils Manual}), whose value should be an
25495 @code{imap4d-configuration} object as in this example:
25498 (service imap4d-service-type
25499 (imap4d-configuration
25500 (config-file (local-file "imap4d.conf"))))
25504 @deftp {Data Type} imap4d-configuration
25505 Data type representing the configuration of @command{imap4d}.
25508 @item @code{package} (default: @code{mailutils})
25509 The package that provides @command{imap4d}.
25511 @item @code{config-file} (default: @code{%default-imap4d-config-file})
25512 File-like object of the configuration file to use, by default it will listen
25513 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
25514 Mailutils Manual}, for details.
25519 @subsubheading Radicale Service
25523 @deffn {Scheme Variable} radicale-service-type
25524 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
25525 server whose value should be a @code{radicale-configuration}.
25528 @deftp {Data Type} radicale-configuration
25529 Data type representing the configuration of @command{radicale}.
25532 @item @code{package} (default: @code{radicale})
25533 The package that provides @command{radicale}.
25535 @item @code{config-file} (default: @code{%default-radicale-config-file})
25536 File-like object of the configuration file to use, by default it will listen
25537 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
25538 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
25543 @node Messaging Services
25544 @subsection Messaging Services
25549 The @code{(gnu services messaging)} module provides Guix service
25550 definitions for messaging services. Currently it provides the following
25553 @subsubheading Prosody Service
25555 @deffn {Scheme Variable} prosody-service-type
25556 This is the type for the @uref{https://prosody.im, Prosody XMPP
25557 communication server}. Its value must be a @code{prosody-configuration}
25558 record as in this example:
25561 (service prosody-service-type
25562 (prosody-configuration
25563 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
25566 (int-component-configuration
25567 (hostname "conference.example.net")
25569 (mod-muc (mod-muc-configuration)))))
25572 (virtualhost-configuration
25573 (domain "example.net"))))))
25576 See below for details about @code{prosody-configuration}.
25580 By default, Prosody does not need much configuration. Only one
25581 @code{virtualhosts} field is needed: it specifies the domain you wish
25584 You can perform various sanity checks on the generated configuration
25585 with the @code{prosodyctl check} command.
25587 Prosodyctl will also help you to import certificates from the
25588 @code{letsencrypt} directory so that the @code{prosody} user can access
25589 them. See @url{https://prosody.im/doc/letsencrypt}.
25592 prosodyctl --root cert import /etc/letsencrypt/live
25595 The available configuration parameters follow. Each parameter
25596 definition is preceded by its type; for example, @samp{string-list foo}
25597 indicates that the @code{foo} parameter should be specified as a list of
25598 strings. Types starting with @code{maybe-} denote parameters that won't
25599 show up in @code{prosody.cfg.lua} when their value is left unspecified.
25601 There is also a way to specify the configuration as a string, if you
25602 have an old @code{prosody.cfg.lua} file that you want to port over from
25603 some other system; see the end for more details.
25605 The @code{file-object} type designates either a file-like object
25606 (@pxref{G-Expressions, file-like objects}) or a file name.
25608 @c The following documentation was initially generated by
25609 @c (generate-documentation) in (gnu services messaging). Manually maintained
25610 @c documentation is better, so we shouldn't hesitate to edit below as
25611 @c needed. However if the change you want to make to this documentation
25612 @c can be done in an automated way, it's probably easier to change
25613 @c (generate-documentation) than to make it below and have to deal with
25614 @c the churn as Prosody updates.
25616 Available @code{prosody-configuration} fields are:
25618 @deftypevr {@code{prosody-configuration} parameter} package prosody
25619 The Prosody package.
25622 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
25623 Location of the Prosody data storage directory. See
25624 @url{https://prosody.im/doc/configure}.
25625 Defaults to @samp{"/var/lib/prosody"}.
25628 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
25629 Additional plugin directories. They are searched in all the specified
25630 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
25631 Defaults to @samp{()}.
25634 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
25635 Every virtual host and component needs a certificate so that clients and
25636 servers can securely verify its identity. Prosody will automatically load
25637 certificates/keys from the directory specified here.
25638 Defaults to @samp{"/etc/prosody/certs"}.
25641 @deftypevr {@code{prosody-configuration} parameter} string-list admins
25642 This is a list of accounts that are admins for the server. Note that you
25643 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
25644 @url{https://prosody.im/doc/creating_accounts}.
25645 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
25646 Defaults to @samp{()}.
25649 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
25650 Enable use of libevent for better performance under high load. See
25651 @url{https://prosody.im/doc/libevent}.
25652 Defaults to @samp{#f}.
25655 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
25656 This is the list of modules Prosody will load on startup. It looks for
25657 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
25658 Documentation on modules can be found at:
25659 @url{https://prosody.im/doc/modules}.
25660 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
25663 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
25664 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
25665 should you want to disable them then add them to this list.
25666 Defaults to @samp{()}.
25669 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
25670 Path to a text file where the shared groups are defined. If this path is
25671 empty then @samp{mod_groups} does nothing. See
25672 @url{https://prosody.im/doc/modules/mod_groups}.
25673 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
25676 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
25677 Disable account creation by default, for security. See
25678 @url{https://prosody.im/doc/creating_accounts}.
25679 Defaults to @samp{#f}.
25682 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
25683 These are the SSL/TLS-related settings. Most of them are disabled so to
25684 use Prosody's defaults. If you do not completely understand these options, do
25685 not add them to your config, it is easy to lower the security of your server
25686 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
25688 Available @code{ssl-configuration} fields are:
25690 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
25691 This determines what handshake to use.
25694 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
25695 Path to your private key file.
25698 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
25699 Path to your certificate file.
25702 @deftypevr {@code{ssl-configuration} parameter} file-object capath
25703 Path to directory containing root certificates that you wish Prosody to
25704 trust when verifying the certificates of remote servers.
25705 Defaults to @samp{"/etc/ssl/certs"}.
25708 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
25709 Path to a file containing root certificates that you wish Prosody to trust.
25710 Similar to @code{capath} but with all certificates concatenated together.
25713 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
25714 A list of verification options (these mostly map to OpenSSL's
25715 @code{set_verify()} flags).
25718 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
25719 A list of general options relating to SSL/TLS@. These map to OpenSSL's
25720 @code{set_options()}. For a full list of options available in LuaSec, see the
25724 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
25725 How long a chain of certificate authorities to check when looking for a
25726 trusted root certificate.
25729 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
25730 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
25731 clients, and in what order.
25734 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
25735 A path to a file containing parameters for Diffie-Hellman key exchange. You
25736 can create such a file with:
25737 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
25740 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
25741 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
25742 @samp{"secp384r1"}.
25745 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
25746 A list of ``extra'' verification options.
25749 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
25750 Password for encrypted private keys.
25755 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
25756 Whether to force all client-to-server connections to be encrypted or not.
25757 See @url{https://prosody.im/doc/modules/mod_tls}.
25758 Defaults to @samp{#f}.
25761 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
25762 Set of mechanisms that will never be offered. See
25763 @url{https://prosody.im/doc/modules/mod_saslauth}.
25764 Defaults to @samp{("DIGEST-MD5")}.
25767 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
25768 Whether to force all server-to-server connections to be encrypted or not.
25769 See @url{https://prosody.im/doc/modules/mod_tls}.
25770 Defaults to @samp{#f}.
25773 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
25774 Whether to require encryption and certificate authentication. This
25775 provides ideal security, but requires servers you communicate with to support
25776 encryption AND present valid, trusted certificates. See
25777 @url{https://prosody.im/doc/s2s#security}.
25778 Defaults to @samp{#f}.
25781 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
25782 Many servers don't support encryption or have invalid or self-signed
25783 certificates. You can list domains here that will not be required to
25784 authenticate using certificates. They will be authenticated using DNS@. See
25785 @url{https://prosody.im/doc/s2s#security}.
25786 Defaults to @samp{()}.
25789 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
25790 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
25791 valid certificates for some domains by specifying a list here. See
25792 @url{https://prosody.im/doc/s2s#security}.
25793 Defaults to @samp{()}.
25796 @deftypevr {@code{prosody-configuration} parameter} string authentication
25797 Select the authentication backend to use. The default provider stores
25798 passwords in plaintext and uses Prosody's configured data storage to store the
25799 authentication data. If you do not trust your server please see
25800 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
25801 about using the hashed backend. See also
25802 @url{https://prosody.im/doc/authentication}
25803 Defaults to @samp{"internal_plain"}.
25806 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
25807 Set logging options. Advanced logging configuration is not yet supported
25808 by the Prosody service. See @url{https://prosody.im/doc/logging}.
25809 Defaults to @samp{"*syslog"}.
25812 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
25813 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
25814 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
25817 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
25818 Maximum allowed size of the HTTP body (in bytes).
25821 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
25822 Some modules expose their own URL in various ways. This URL is built
25823 from the protocol, host and port used. If Prosody sits behind a proxy, the
25824 public URL will be @code{http-external-url} instead. See
25825 @url{https://prosody.im/doc/http#external_url}.
25828 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
25829 A host in Prosody is a domain on which user accounts can be created. For
25830 example if you want your users to have addresses like
25831 @samp{"john.smith@@example.com"} then you need to add a host
25832 @samp{"example.com"}. All options in this list will apply only to this host.
25835 The name @emph{virtual} host is used in configuration to avoid confusion with
25836 the actual physical host that Prosody is installed on. A single Prosody
25837 instance can serve many domains, each one defined as a VirtualHost entry in
25838 Prosody's configuration. Conversely a server that hosts a single domain would
25839 have just one VirtualHost entry.
25841 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
25844 Available @code{virtualhost-configuration} fields are:
25846 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:
25847 @deftypevr {@code{virtualhost-configuration} parameter} string domain
25848 Domain you wish Prosody to serve.
25853 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
25854 Components are extra services on a server which are available to clients,
25855 usually on a subdomain of the main server (such as
25856 @samp{"mycomponent.example.com"}). Example components might be chatroom
25857 servers, user directories, or gateways to other protocols.
25859 Internal components are implemented with Prosody-specific plugins. To add an
25860 internal component, you simply fill the hostname field, and the plugin you wish
25861 to use for the component.
25863 See @url{https://prosody.im/doc/components}.
25864 Defaults to @samp{()}.
25866 Available @code{int-component-configuration} fields are:
25868 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:
25869 @deftypevr {@code{int-component-configuration} parameter} string hostname
25870 Hostname of the component.
25873 @deftypevr {@code{int-component-configuration} parameter} string plugin
25874 Plugin you wish to use for the component.
25877 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
25878 Multi-user chat (MUC) is Prosody's module for allowing you to create
25879 hosted chatrooms/conferences for XMPP users.
25881 General information on setting up and using multi-user chatrooms can be found
25882 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
25883 which you should read if you are new to XMPP chatrooms.
25885 See also @url{https://prosody.im/doc/modules/mod_muc}.
25887 Available @code{mod-muc-configuration} fields are:
25889 @deftypevr {@code{mod-muc-configuration} parameter} string name
25890 The name to return in service discovery responses.
25891 Defaults to @samp{"Prosody Chatrooms"}.
25894 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
25895 If @samp{#t}, this will only allow admins to create new chatrooms.
25896 Otherwise anyone can create a room. The value @samp{"local"} restricts room
25897 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
25898 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
25899 restricts to service administrators only.
25900 Defaults to @samp{#f}.
25903 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
25904 Maximum number of history messages that will be sent to the member that has
25905 just joined the room.
25906 Defaults to @samp{20}.
25913 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
25914 External components use XEP-0114, which most standalone components
25915 support. To add an external component, you simply fill the hostname field. See
25916 @url{https://prosody.im/doc/components}.
25917 Defaults to @samp{()}.
25919 Available @code{ext-component-configuration} fields are:
25921 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:
25922 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
25923 Password which the component will use to log in.
25926 @deftypevr {@code{ext-component-configuration} parameter} string hostname
25927 Hostname of the component.
25932 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
25933 Port(s) Prosody listens on for component connections.
25934 Defaults to @samp{(5347)}.
25937 @deftypevr {@code{prosody-configuration} parameter} string component-interface
25938 Interface Prosody listens on for component connections.
25939 Defaults to @samp{"127.0.0.1"}.
25942 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
25943 Raw content that will be added to the configuration file.
25946 It could be that you just want to get a @code{prosody.cfg.lua}
25947 up and running. In that case, you can pass an
25948 @code{opaque-prosody-configuration} record as the value of
25949 @code{prosody-service-type}. As its name indicates, an opaque configuration
25950 does not have easy reflective capabilities.
25951 Available @code{opaque-prosody-configuration} fields are:
25953 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
25954 The prosody package.
25957 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
25958 The contents of the @code{prosody.cfg.lua} to use.
25961 For example, if your @code{prosody.cfg.lua} is just the empty
25962 string, you could instantiate a prosody service like this:
25965 (service prosody-service-type
25966 (opaque-prosody-configuration
25967 (prosody.cfg.lua "")))
25970 @c end of Prosody auto-generated documentation
25972 @subsubheading BitlBee Service
25974 @cindex IRC (Internet Relay Chat)
25975 @cindex IRC gateway
25976 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
25977 interface to a variety of messaging protocols such as XMPP.
25979 @defvr {Scheme Variable} bitlbee-service-type
25980 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
25981 gateway daemon. Its value is a @code{bitlbee-configuration} (see
25984 To have BitlBee listen on port 6667 on localhost, add this line to your
25988 (service bitlbee-service-type)
25992 @deftp {Data Type} bitlbee-configuration
25993 This is the configuration for BitlBee, with the following fields:
25996 @item @code{interface} (default: @code{"127.0.0.1"})
25997 @itemx @code{port} (default: @code{6667})
25998 Listen on the network interface corresponding to the IP address
25999 specified in @var{interface}, on @var{port}.
26001 When @var{interface} is @code{127.0.0.1}, only local clients can
26002 connect; when it is @code{0.0.0.0}, connections can come from any
26003 networking interface.
26005 @item @code{bitlbee} (default: @code{bitlbee})
26006 The BitlBee package to use.
26008 @item @code{plugins} (default: @code{'()})
26009 List of plugin packages to use---e.g., @code{bitlbee-discord}.
26011 @item @code{extra-settings} (default: @code{""})
26012 Configuration snippet added as-is to the BitlBee configuration file.
26016 @subsubheading Quassel Service
26018 @cindex IRC (Internet Relay Chat)
26019 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
26020 meaning that one or more clients can attach to and detach from the
26023 @defvr {Scheme Variable} quassel-service-type
26024 This is the service type for the @url{https://quassel-irc.org/,Quassel}
26025 IRC backend daemon. Its value is a @code{quassel-configuration}
26029 @deftp {Data Type} quassel-configuration
26030 This is the configuration for Quassel, with the following fields:
26033 @item @code{quassel} (default: @code{quassel})
26034 The Quassel package to use.
26036 @item @code{interface} (default: @code{"::,0.0.0.0"})
26037 @item @code{port} (default: @code{4242})
26038 Listen on the network interface(s) corresponding to the IPv4 or IPv6
26039 interfaces specified in the comma delimited @var{interface}, on
26042 @item @code{loglevel} (default: @code{"Info"})
26043 The level of logging desired. Accepted values are Debug, Info, Warning
26048 @node Telephony Services
26049 @subsection Telephony Services
26051 @cindex telephony, services
26052 The @code{(gnu services telephony)} module contains Guix service
26053 definitions for telephony services. Currently it provides the following
26056 @subsubheading Jami
26058 @cindex jami, service
26060 This section describes how to configure a Jami server that can be used
26061 to host video (or audio) conferences, among other uses. The following
26062 example demonstrates how to specify Jami account archives (backups) to
26063 be provisioned automatically:
26066 (service jami-service-type
26067 (jami-configuration
26069 (list (jami-account
26070 (archive "/etc/jami/unencrypted-account-1.gz"))
26072 (archive "/etc/jami/unencrypted-account-2.gz"))))))
26075 When the accounts field is specified, the Jami account files of the
26076 service found under @file{/var/lib/jami} are recreated every time the
26079 Jami accounts and their corresponding backup archives can be generated
26080 using the @code{jami} or @code{jami-gnome} Jami clients. The accounts
26081 should not be password-protected, but it is wise to ensure their files
26082 are only readable by @samp{root}.
26084 The next example shows how to declare that only some contacts should be
26085 allowed to communicate with a given account:
26088 (service jami-service-type
26089 (jami-configuration
26091 (list (jami-account
26092 (archive "/etc/jami/unencrypted-account-1.gz")
26093 (peer-discovery? #t)
26094 (rendezvous-point? #t)
26096 '("1dbcb0f5f37324228235564b79f2b9737e9a008f"
26097 "2dbcb0f5f37324228235564b79f2b9737e9a008f")))))))
26100 In this mode, only the declared @code{allowed-contacts} can initiate
26101 communication with the Jami account. This can be used, for example,
26102 with rendezvous point accounts to create a private video conferencing
26105 To put the system administrator in full control of the conferences
26106 hosted on their system, the Jami service supports the following actions:
26109 # herd doc jami list-actions
26111 list-account-details
26112 list-banned-contacts
26121 The above actions aim to provide the most valuable actions for
26122 moderation purposes, not to cover the whole Jami API. Users wanting to
26123 interact with the Jami daemon from Guile may be interested in
26124 experimenting with the @code{(gnu build jami-service)} module, which
26125 powers the above Shepherd actions.
26127 @c TODO: This should be auto-generated from the doc already defined on
26128 @c the shepherd-actions themselves in (gnu services telephony).
26129 The @code{add-moderator} and @code{ban-contact} actions accept a contact
26130 @emph{fingerprint} (40 characters long hash) as first argument and an
26131 account fingerprint or username as second argument:
26134 # herd add-moderator jami 1dbcb0f5f37324228235564b79f2b9737e9a008f \
26135 f3345f2775ddfe07a4b0d95daea111d15fbc1199
26137 # herd list-moderators jami
26138 Moderators for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26139 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26143 In the case of @code{ban-contact}, the second username argument is
26144 optional; when omitted, the account is banned from all Jami accounts:
26147 # herd ban-contact jami 1dbcb0f5f37324228235564b79f2b9737e9a008f
26149 # herd list-banned-contacts jami
26150 Banned contacts for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26151 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26155 Banned contacts are also stripped from their moderation privileges.
26157 The @code{disable-account} action allows to completely disconnect an
26158 account from the network, making it unreachable, while
26159 @code{enable-account} does the inverse. They accept a single account
26160 username or fingerprint as first argument:
26163 # herd disable-account jami f3345f2775ddfe07a4b0d95daea111d15fbc1199
26165 # herd list-accounts jami
26166 The following Jami accounts are available:
26167 - f3345f2775ddfe07a4b0d95daea111d15fbc1199 (dummy) [disabled]
26171 The @code{list-account-details} action prints the detailed parameters of
26172 each accounts in the Recutils format, which means the @command{recsel}
26173 command can be used to select accounts of interest (@pxref{Selection
26174 Expressions,,,recutils, GNU recutils manual}). Note that period
26175 characters (@samp{.}) found in the account parameter keys are mapped to
26176 underscores (@samp{_}) in the output, to meet the requirements of the
26177 Recutils format. The following example shows how to print the account
26178 fingerprints for all accounts operating in the rendezvous point mode:
26181 # herd list-account-details jami | \
26182 recsel -p Account.username -e 'Account.rendezVous ~ "true"'
26183 Account_username: f3345f2775ddfe07a4b0d95daea111d15fbc1199
26186 The remaining actions should be self-explanatory.
26188 The complete set of available configuration options is detailed below.
26190 @c TODO: Ideally, the following fragments would be auto-generated at
26191 @c build time, so that they needn't be manually duplicated.
26192 @c Auto-generated via (configuration->documentation 'jami-configuration)
26193 @deftp {Data Type} jami-configuration
26194 Available @code{jami-configuration} fields are:
26197 @item @code{libjami} (default: @code{libjami}) (type: package)
26198 The Jami daemon package to use.
26200 @item @code{dbus} (default: @code{dbus-for-jami}) (type: package)
26201 The D-Bus package to use to start the required D-Bus session.
26203 @item @code{nss-certs} (default: @code{nss-certs}) (type: package)
26204 The nss-certs package to use to provide TLS certificates.
26206 @item @code{enable-logging?} (default: @code{#t}) (type: boolean)
26207 Whether to enable logging to syslog.
26209 @item @code{debug?} (default: @code{#f}) (type: boolean)
26210 Whether to enable debug level messages.
26212 @item @code{auto-answer?} (default: @code{#f}) (type: boolean)
26213 Whether to force automatic answer to incoming calls.
26215 @item @code{accounts} (type: maybe-jami-account-list)
26216 A list of Jami accounts to be (re-)provisioned every time the Jami
26217 daemon service starts. When providing this field, the account
26218 directories under @file{/var/lib/jami/} are recreated every time the
26219 service starts, ensuring a consistent state.
26225 @c Auto-generated via (configuration->documentation 'jami-account)
26226 @deftp {Data Type} jami-account
26227 Available @code{jami-account} fields are:
26230 @item @code{archive} (type: string-or-computed-file)
26231 The account archive (backup) file name of the account. This is used to
26232 provision the account when the service starts. The account archive
26233 should @emph{not} be encrypted. It is highly recommended to make it
26234 readable only to the @samp{root} user (i.e., not in the store), to guard
26235 against leaking the secret key material of the Jami account it contains.
26237 @item @code{allowed-contacts} (type: maybe-account-fingerprint-list)
26238 The list of allowed contacts for the account, entered as their 40
26239 characters long fingerprint. Messages or calls from accounts not in
26240 that list will be rejected. When left specified, the configuration of
26241 the account archive is used as-is with respect to contacts and public
26242 inbound calls/messaging allowance, which typically defaults to allow any
26243 contact to communicate with the account.
26245 @item @code{moderators} (type: maybe-account-fingerprint-list)
26246 The list of contacts that should have moderation privileges (to ban,
26247 mute, etc. other users) in rendezvous conferences, entered as their 40
26248 characters long fingerprint. When left unspecified, the configuration
26249 of the account archive is used as-is with respect to moderation, which
26250 typically defaults to allow anyone to moderate.
26252 @item @code{rendezvous-point?} (type: maybe-boolean)
26253 Whether the account should operate in the rendezvous mode. In this
26254 mode, all the incoming audio/video calls are mixed into a conference.
26255 When left unspecified, the value from the account archive prevails.
26257 @item @code{peer-discovery?} (type: maybe-boolean)
26258 Whether peer discovery should be enabled. Peer discovery is used to
26259 discover other OpenDHT nodes on the local network, which can be useful
26260 to maintain communication between devices on such network even when the
26261 connection to the the Internet has been lost. When left unspecified,
26262 the value from the account archive prevails.
26264 @item @code{bootstrap-hostnames} (type: maybe-string-list)
26265 A list of hostnames or IPs pointing to OpenDHT nodes, that should be
26266 used to initially join the OpenDHT network. When left unspecified, the
26267 value from the account archive prevails.
26269 @item @code{name-server-uri} (type: maybe-string)
26270 The URI of the name server to use, that can be used to retrieve the
26271 account fingerprint for a registered username.
26277 @subsubheading Mumble server
26281 @cindex VoIP server
26282 This section describes how to set up and run a
26283 @uref{https://mumble.info, Mumble} server (formerly known as Murmur).
26285 @deftp {Data Type} mumble-server-configuration
26286 The service type for the Mumble server. An example configuration can
26290 (service mumble-server-service-type
26291 (mumble-server-configuration
26293 "Welcome to this Mumble server running on Guix!")
26294 (cert-required? #t) ;disallow text password logins
26295 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
26296 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
26299 After reconfiguring your system, you can manually set the mumble-server
26301 password with the command that is printed during the activation phase.
26303 It is recommended to register a normal Mumble user account
26304 and grant it admin or moderator rights.
26305 You can use the @code{mumble} client to
26306 login as new normal user, register yourself, and log out.
26307 For the next step login with the name @code{SuperUser} use
26308 the @code{SuperUser} password that you set previously,
26309 and grant your newly registered mumble user administrator or moderator
26310 rights and create some channels.
26312 Available @code{mumble-server-configuration} fields are:
26315 @item @code{package} (default: @code{mumble})
26316 Package that contains @code{bin/mumble-server}.
26318 @item @code{user} (default: @code{"mumble-server"})
26319 User who will run the Mumble-Server server.
26321 @item @code{group} (default: @code{"mumble-server"})
26322 Group of the user who will run the mumble-server server.
26324 @item @code{port} (default: @code{64738})
26325 Port on which the server will listen.
26327 @item @code{welcome-text} (default: @code{""})
26328 Welcome text sent to clients when they connect.
26330 @item @code{server-password} (default: @code{""})
26331 Password the clients have to enter in order to connect.
26333 @item @code{max-users} (default: @code{100})
26334 Maximum of users that can be connected to the server at once.
26336 @item @code{max-user-bandwidth} (default: @code{#f})
26337 Maximum voice traffic a user can send per second.
26339 @item @code{database-file} (default: @code{"/var/lib/mumble-server/db.sqlite"})
26340 File name of the sqlite database.
26341 The service's user will become the owner of the directory.
26343 @item @code{log-file} (default: @code{"/var/log/mumble-server/mumble-server.log"})
26344 File name of the log file.
26345 The service's user will become the owner of the directory.
26347 @item @code{autoban-attempts} (default: @code{10})
26348 Maximum number of logins a user can make in @code{autoban-timeframe}
26349 without getting auto banned for @code{autoban-time}.
26351 @item @code{autoban-timeframe} (default: @code{120})
26352 Timeframe for autoban in seconds.
26354 @item @code{autoban-time} (default: @code{300})
26355 Amount of time in seconds for which a client gets banned
26356 when violating the autoban limits.
26358 @item @code{opus-threshold} (default: @code{100})
26359 Percentage of clients that need to support opus
26360 before switching over to opus audio codec.
26362 @item @code{channel-nesting-limit} (default: @code{10})
26363 How deep channels can be nested at maximum.
26365 @item @code{channelname-regex} (default: @code{#f})
26366 A string in form of a Qt regular expression that channel names must conform to.
26368 @item @code{username-regex} (default: @code{#f})
26369 A string in form of a Qt regular expression that user names must conform to.
26371 @item @code{text-message-length} (default: @code{5000})
26372 Maximum size in bytes that a user can send in one text chat message.
26374 @item @code{image-message-length} (default: @code{(* 128 1024)})
26375 Maximum size in bytes that a user can send in one image message.
26377 @item @code{cert-required?} (default: @code{#f})
26378 If it is set to @code{#t} clients that use weak password authentication
26379 will not be accepted. Users must have completed the certificate wizard to join.
26381 @item @code{remember-channel?} (default: @code{#f})
26382 Should mumble-server remember the last channel each user was in when
26383 they disconnected and put them into the remembered channel when they
26386 @item @code{allow-html?} (default: @code{#f})
26387 Should html be allowed in text messages, user comments, and channel descriptions.
26389 @item @code{allow-ping?} (default: @code{#f})
26390 Setting to true exposes the current user count, the maximum user count, and
26391 the server's maximum bandwidth per client to unauthenticated users. In the
26392 Mumble client, this information is shown in the Connect dialog.
26394 Disabling this setting will prevent public listing of the server.
26396 @item @code{bonjour?} (default: @code{#f})
26397 Should the server advertise itself in the local network through the bonjour protocol.
26399 @item @code{send-version?} (default: @code{#f})
26400 Should the mumble-server server version be exposed in ping requests.
26402 @item @code{log-days} (default: @code{31})
26403 Mumble also stores logs in the database, which are accessible via RPC.
26404 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
26405 or -1 to disable logging to the database.
26407 @item @code{obfuscate-ips?} (default: @code{#t})
26408 Should logged ips be obfuscated to protect the privacy of users.
26410 @item @code{ssl-cert} (default: @code{#f})
26411 File name of the SSL/TLS certificate used for encrypted connections.
26414 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
26416 @item @code{ssl-key} (default: @code{#f})
26417 Filepath to the ssl private key used for encrypted connections.
26419 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
26422 @item @code{ssl-dh-params} (default: @code{#f})
26423 File name of a PEM-encoded file with Diffie-Hellman parameters
26424 for the SSL/TLS encryption. Alternatively you set it to
26425 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
26426 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
26428 @item @code{ssl-ciphers} (default: @code{#f})
26429 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
26432 This option is specified using
26433 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
26434 OpenSSL cipher list notation}.
26436 It is recommended that you try your cipher string using
26437 'openssl ciphers <string>' before setting it here, to get a feel for
26438 which cipher suites you will get.
26439 After setting this option, it is recommend that you inspect your Mumble
26440 server log to ensure that Mumble is using the cipher suites that you
26444 Changing this option may impact the backwards compatibility of your
26445 Mumble-Server server, and can remove the ability for older Mumble clients to be able to connect to it.
26448 @item @code{public-registration} (default: @code{#f})
26449 Must be a @code{<mumble-server-public-registration-configuration>}
26450 record or @code{#f}.
26452 You can optionally register your server in the public server list that the
26453 @code{mumble} client shows on startup.
26454 You cannot register your server if you have set a @code{server-password},
26455 or set @code{allow-ping} to @code{#f}.
26457 It might take a few hours until it shows up in the public list.
26459 @item @code{file} (default: @code{#f})
26460 Optional alternative override for this configuration.
26464 @deftp {Data Type} mumble-server-public-registration-configuration
26465 Configuration for public registration of a mumble-server service.
26469 This is a display name for your server. Not to be confused with the hostname.
26471 @item @code{password}
26472 A password to identify your registration.
26473 Subsequent updates will need the same password. Don't lose your password.
26476 This should be a @code{http://} or @code{https://} link to your web
26479 @item @code{hostname} (default: @code{#f})
26480 By default your server will be listed by its IP address.
26481 If it is set your server will be linked by this host name instead.
26485 @quotation Deprecation notice
26486 Due to historical reasons, all of the above @code{mumble-server-}
26487 procedures are also exported with the @code{murmur-} prefix.
26488 It is recommended that you switch to using @code{mumble-server-}
26492 @node File-Sharing Services
26493 @subsection File-Sharing Services
26495 The @code{(gnu services file-sharing)} module provides services that
26496 assist with transferring files over peer-to-peer file-sharing networks.
26498 @subsubheading Transmission Daemon Service
26500 @uref{https://transmissionbt.com/, Transmission} is a flexible
26501 BitTorrent client that offers a variety of graphical and command-line
26502 interfaces. A @code{transmission-daemon-service-type} service provides
26503 Transmission's headless variant, @command{transmission-daemon}, as a
26504 system service, allowing users to share files via BitTorrent even when
26505 they are not logged in.
26507 @deffn {Scheme Variable} transmission-daemon-service-type
26508 The service type for the Transmission Daemon BitTorrent client. Its
26509 value must be a @code{transmission-daemon-configuration} object as in
26513 (service transmission-daemon-service-type
26514 (transmission-daemon-configuration
26515 ;; Restrict access to the RPC ("control") interface
26516 (rpc-authentication-required? #t)
26517 (rpc-username "transmission")
26519 (transmission-password-hash
26520 "transmission" ; desired password
26521 "uKd1uMs9")) ; arbitrary salt value
26523 ;; Accept requests from this and other hosts on the
26525 (rpc-whitelist-enabled? #t)
26526 (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
26528 ;; Limit bandwidth use during work hours
26529 (alt-speed-down (* 1024 2)) ; 2 MB/s
26530 (alt-speed-up 512) ; 512 kB/s
26532 (alt-speed-time-enabled? #t)
26533 (alt-speed-time-day 'weekdays)
26534 (alt-speed-time-begin
26535 (+ (* 60 8) 30)) ; 8:30 am
26536 (alt-speed-time-end
26537 (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
26541 Once the service is started, users can interact with the daemon through
26542 its Web interface (at @code{http://localhost:9091/}) or by using the
26543 @command{transmission-remote} command-line tool, available in the
26544 @code{transmission} package. (Emacs users may want to also consider the
26545 @code{emacs-transmission} package.) Both communicate with the daemon
26546 through its remote procedure call (RPC) interface, which by default is
26547 available to all users on the system; you may wish to change this by
26548 assigning values to the @code{rpc-authentication-required?},
26549 @code{rpc-username} and @code{rpc-password} settings, as shown in the
26550 example above and documented further below.
26552 The value for @code{rpc-password} must be a password hash of the type
26553 generated and used by Transmission clients. This can be copied verbatim
26554 from an existing @file{settings.json} file, if another Transmission
26555 client is already being used. Otherwise, the
26556 @code{transmission-password-hash} and @code{transmission-random-salt}
26557 procedures provided by this module can be used to obtain a suitable hash
26560 @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
26561 Returns a string containing the result of hashing @var{password}
26562 together with @var{salt}, in the format recognized by Transmission
26563 clients for their @code{rpc-password} configuration setting.
26565 @var{salt} must be an eight-character string. The
26566 @code{transmission-random-salt} procedure can be used to generate a
26567 suitable salt value at random.
26570 @deffn {Scheme Procedure} transmission-random-salt
26571 Returns a string containing a random, eight-character salt value of the
26572 type generated and used by Transmission clients, suitable for passing to
26573 the @code{transmission-password-hash} procedure.
26576 These procedures are accessible from within a Guile REPL started with
26577 the @command{guix repl} command (@pxref{Invoking guix repl}). This is
26578 useful for obtaining a random salt value to provide as the second
26579 parameter to `transmission-password-hash`, as in this example session:
26583 scheme@@(guix-user)> ,use (gnu services file-sharing)
26584 scheme@@(guix-user)> (transmission-random-salt)
26588 Alternatively, a complete password hash can generated in a single step:
26591 scheme@@(guix-user)> (transmission-password-hash "transmission"
26592 (transmission-random-salt))
26593 $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
26596 The resulting string can be used as-is for the value of
26597 @code{rpc-password}, allowing the password to be kept hidden even in the
26598 operating-system configuration.
26600 Torrent files downloaded by the daemon are directly accessible only to
26601 users in the ``transmission'' user group, who receive read-only access
26602 to the directory specified by the @code{download-dir} configuration
26603 setting (and also the directory specified by @code{incomplete-dir}, if
26604 @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
26605 moved to another directory or deleted altogether using
26606 @command{transmission-remote} with its @code{--move} and
26607 @code{--remove-and-delete} options.
26609 If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
26610 the ``transmission'' group are able also to place @file{.torrent} files
26611 in the directory specified by @code{watch-dir} to have the corresponding
26612 torrents added by the daemon. (The @code{trash-original-torrent-files?}
26613 setting controls whether the daemon deletes these files after processing
26616 Some of the daemon's configuration settings can be changed temporarily
26617 by @command{transmission-remote} and similar tools. To undo these
26618 changes, use the service's @code{reload} action to have the daemon
26619 reload its settings from disk:
26622 # herd reload transmission-daemon
26625 The full set of available configuration settings is defined by the
26626 @code{transmission-daemon-configuration} data type.
26628 @deftp {Data Type} transmission-daemon-configuration
26629 The data type representing configuration settings for Transmission
26630 Daemon. These correspond directly to the settings recognized by
26631 Transmission clients in their @file{settings.json} file.
26634 @c The following documentation was initially generated by
26635 @c (generate-transmission-daemon-documentation) in (gnu services
26636 @c file-sharing). Manually maintained documentation is better, so we
26637 @c shouldn't hesitate to edit below as needed. However if the change
26638 @c you want to make to this documentation can be done in an automated
26639 @c way, it's probably easier to change (generate-documentation) than to
26640 @c make it below and have to deal with the churn as Transmission Daemon
26643 @c %start of fragment
26645 Available @code{transmission-daemon-configuration} fields are:
26647 @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
26648 The Transmission package to use.
26652 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
26653 The period, in seconds, to wait when stopping the service for
26654 @command{transmission-daemon} to exit before killing its process. This
26655 allows the daemon time to complete its housekeeping and send a final
26656 update to trackers as it shuts down. On slow hosts, or hosts with a
26657 slow network connection, this value may need to be increased.
26659 Defaults to @samp{10}.
26663 @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
26664 The directory to which torrent files are downloaded.
26666 Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
26670 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
26671 If @code{#t}, files will be held in @code{incomplete-dir} while their
26672 torrent is being downloaded, then moved to @code{download-dir} once the
26673 torrent is complete. Otherwise, files for all torrents (including those
26674 still being downloaded) will be placed in @code{download-dir}.
26676 Defaults to @samp{#f}.
26680 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
26681 The directory in which files from incompletely downloaded torrents will
26682 be held when @code{incomplete-dir-enabled?} is @code{#t}.
26684 Defaults to @samp{disabled}.
26688 @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
26689 The file mode creation mask used for downloaded files. (See the
26690 @command{umask} man page for more information.)
26692 Defaults to @samp{18}.
26696 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
26697 When @code{#t}, ``.part'' is appended to the name of partially
26700 Defaults to @samp{#t}.
26704 @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
26705 The mode by which space should be preallocated for downloaded files, one
26706 of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
26707 Specifying @code{full} will minimize disk fragmentation at a cost to
26708 file-creation speed.
26710 Defaults to @samp{fast}.
26714 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
26715 If @code{#t}, the directory specified by @code{watch-dir} will be
26716 watched for new @file{.torrent} files and the torrents they describe
26717 added automatically (and the original files removed, if
26718 @code{trash-original-torrent-files?} is @code{#t}).
26720 Defaults to @samp{#f}.
26724 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
26725 The directory to be watched for @file{.torrent} files indicating new
26726 torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
26728 Defaults to @samp{disabled}.
26732 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
26733 When @code{#t}, @file{.torrent} files will be deleted from the watch
26734 directory once their torrent has been added (see
26735 @code{watch-directory-enabled?}).
26737 Defaults to @samp{#f}.
26741 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
26742 When @code{#t}, the daemon's download speed will be limited to the rate
26743 specified by @code{speed-limit-down}.
26745 Defaults to @samp{#f}.
26749 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
26750 The default global-maximum download speed, in kilobytes per second.
26752 Defaults to @samp{100}.
26756 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
26757 When @code{#t}, the daemon's upload speed will be limited to the rate
26758 specified by @code{speed-limit-up}.
26760 Defaults to @samp{#f}.
26764 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
26765 The default global-maximum upload speed, in kilobytes per second.
26767 Defaults to @samp{100}.
26771 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
26772 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
26773 @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
26774 @code{speed-limit-up}, if they are enabled) to constrain the daemon's
26775 bandwidth usage. This can be scheduled to occur automatically at
26776 certain times during the week; see @code{alt-speed-time-enabled?}.
26778 Defaults to @samp{#f}.
26782 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
26783 The alternate global-maximum download speed, in kilobytes per second.
26785 Defaults to @samp{50}.
26789 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
26790 The alternate global-maximum upload speed, in kilobytes per second.
26792 Defaults to @samp{50}.
26796 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
26797 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
26798 @code{alt-speed-up} will be enabled automatically during the periods
26799 specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
26800 @code{alt-time-speed-end}.
26802 Defaults to @samp{#f}.
26806 @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
26807 The days of the week on which the alternate-speed schedule should be
26808 used, specified either as a list of days (@code{sunday}, @code{monday},
26809 and so on) or using one of the symbols @code{weekdays}, @code{weekends}
26812 Defaults to @samp{all}.
26816 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
26817 The time of day at which to enable the alternate speed limits, expressed
26818 as a number of minutes since midnight.
26820 Defaults to @samp{540}.
26824 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
26825 The time of day at which to disable the alternate speed limits,
26826 expressed as a number of minutes since midnight.
26828 Defaults to @samp{1020}.
26832 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
26833 The IP address at which to listen for peer connections, or ``0.0.0.0''
26834 to listen at all available IP addresses.
26836 Defaults to @samp{"0.0.0.0"}.
26840 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
26841 The IPv6 address at which to listen for peer connections, or ``::'' to
26842 listen at all available IPv6 addresses.
26844 Defaults to @samp{"::"}.
26848 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
26849 If @code{#t}, when the daemon starts it will select a port at random on
26850 which to listen for peer connections, from the range specified
26851 (inclusively) by @code{peer-port-random-low} and
26852 @code{peer-port-random-high}. Otherwise, it listens on the port
26853 specified by @code{peer-port}.
26855 Defaults to @samp{#f}.
26859 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
26860 The lowest selectable port number when @code{peer-port-random-on-start?}
26863 Defaults to @samp{49152}.
26867 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
26868 The highest selectable port number when @code{peer-port-random-on-start}
26871 Defaults to @samp{65535}.
26875 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
26876 The port on which to listen for peer connections when
26877 @code{peer-port-random-on-start?} is @code{#f}.
26879 Defaults to @samp{51413}.
26883 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
26884 If @code{#t}, the daemon will attempt to configure port-forwarding on an
26885 upstream gateway automatically using @acronym{UPnP} and
26888 Defaults to @samp{#t}.
26892 @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
26893 The encryption preference for peer connections, one of
26894 @code{prefer-unencrypted-connections},
26895 @code{prefer-encrypted-connections} or
26896 @code{require-encrypted-connections}.
26898 Defaults to @samp{prefer-encrypted-connections}.
26902 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
26903 The TCP congestion-control algorithm to use for peer connections,
26904 specified using a string recognized by the operating system in calls to
26905 @code{setsockopt}. When left unspecified, the operating-system default
26908 Note that on GNU/Linux systems, the kernel must be configured to allow
26909 processes to use a congestion-control algorithm not in the default set;
26910 otherwise, it will deny these requests with ``Operation not permitted''.
26911 To see which algorithms are available on your system and which are
26912 currently permitted for use, look at the contents of the files
26913 @file{tcp_available_congestion_control} and
26914 @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
26917 As an example, to have Transmission Daemon use
26918 @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
26919 congestion-control algorithm}, you'll need to modify your kernel
26920 configuration to build in support for the algorithm, then update your
26921 operating-system configuration to allow its use by adding a
26922 @code{sysctl-service-type} service (or updating the existing one's
26923 configuration) with lines like the following:
26926 (service sysctl-service-type
26927 (sysctl-configuration
26929 ("net.ipv4.tcp_allowed_congestion_control" .
26930 "reno cubic lp"))))
26933 The Transmission Daemon configuration can then be updated with
26936 (peer-congestion-algorithm "lp")
26939 and the system reconfigured to have the changes take effect.
26941 Defaults to @samp{disabled}.
26945 @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
26946 The type of service to request in outgoing @acronym{TCP} packets, one of
26947 @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
26948 @code{reliability}.
26950 Defaults to @samp{default}.
26954 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
26955 The global limit on the number of connected peers.
26957 Defaults to @samp{200}.
26961 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
26962 The per-torrent limit on the number of connected peers.
26964 Defaults to @samp{50}.
26968 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
26969 The maximum number of peers to which the daemon will upload data
26970 simultaneously for each torrent.
26972 Defaults to @samp{14}.
26976 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
26977 The maximum lifespan, in hours, of the peer ID associated with each
26978 public torrent before it is regenerated.
26980 Defaults to @samp{6}.
26984 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
26985 When @code{#t}, the daemon will ignore peers mentioned in the blocklist
26986 it has most recently downloaded from @code{blocklist-url}.
26988 Defaults to @samp{#f}.
26992 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
26993 The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
26994 @file{.dat} format) to be periodically downloaded and applied when
26995 @code{blocklist-enabled?} is @code{#t}.
26997 Defaults to @samp{disabled}.
27001 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
27002 If @code{#t}, the daemon will be limited to downloading at most
27003 @code{download-queue-size} non-stalled torrents simultaneously.
27005 Defaults to @samp{#t}.
27009 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
27010 The size of the daemon's download queue, which limits the number of
27011 non-stalled torrents it will download at any one time when
27012 @code{download-queue-enabled?} is @code{#t}.
27014 Defaults to @samp{5}.
27018 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
27019 If @code{#t}, the daemon will be limited to seeding at most
27020 @code{seed-queue-size} non-stalled torrents simultaneously.
27022 Defaults to @samp{#f}.
27026 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
27027 The size of the daemon's seed queue, which limits the number of
27028 non-stalled torrents it will seed at any one time when
27029 @code{seed-queue-enabled?} is @code{#t}.
27031 Defaults to @samp{10}.
27035 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
27036 When @code{#t}, the daemon will consider torrents for which it has not
27037 shared data in the past @code{queue-stalled-minutes} minutes to be
27038 stalled and not count them against its @code{download-queue-size} and
27039 @code{seed-queue-size} limits.
27041 Defaults to @samp{#t}.
27045 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
27046 The maximum period, in minutes, a torrent may be idle before it is
27047 considered to be stalled, when @code{queue-stalled-enabled?} is
27050 Defaults to @samp{30}.
27054 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
27055 When @code{#t}, a torrent being seeded will automatically be paused once
27056 it reaches the ratio specified by @code{ratio-limit}.
27058 Defaults to @samp{#f}.
27062 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
27063 The ratio at which a torrent being seeded will be paused, when
27064 @code{ratio-limit-enabled?} is @code{#t}.
27066 Defaults to @samp{2.0}.
27070 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
27071 When @code{#t}, a torrent being seeded will automatically be paused once
27072 it has been idle for @code{idle-seeding-limit} minutes.
27074 Defaults to @samp{#f}.
27078 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
27079 The maximum period, in minutes, a torrent being seeded may be idle
27080 before it is paused, when @code{idle-seeding-limit-enabled?} is
27083 Defaults to @samp{30}.
27087 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
27088 Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
27089 hash table (@acronym{DHT}) protocol}, which supports the use of
27090 trackerless torrents.
27092 Defaults to @samp{#t}.
27096 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
27097 Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
27098 peer discovery} (@acronym{LPD}), which allows the discovery of peers on
27099 the local network and may reduce the amount of data sent over the public
27102 Defaults to @samp{#f}.
27106 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
27107 Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
27108 (@acronym{PEX}), which reduces the daemon's reliance on external
27109 trackers and may improve its performance.
27111 Defaults to @samp{#t}.
27115 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
27116 Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
27117 transport protocol} (@acronym{uTP}), which aims to reduce the impact of
27118 BitTorrent traffic on other users of the local network while maintaining
27119 full utilization of the available bandwidth.
27121 Defaults to @samp{#t}.
27125 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
27126 If @code{#t}, enable the remote procedure call (@acronym{RPC})
27127 interface, which allows remote control of the daemon via its Web
27128 interface, the @command{transmission-remote} command-line client, and
27131 Defaults to @samp{#t}.
27135 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
27136 The IP address at which to listen for @acronym{RPC} connections, or
27137 ``0.0.0.0'' to listen at all available IP addresses.
27139 Defaults to @samp{"0.0.0.0"}.
27143 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
27144 The port on which to listen for @acronym{RPC} connections.
27146 Defaults to @samp{9091}.
27150 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
27151 The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
27153 Defaults to @samp{"/transmission/"}.
27157 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
27158 When @code{#t}, clients must authenticate (see @code{rpc-username} and
27159 @code{rpc-password}) when using the @acronym{RPC} interface. Note this
27160 has the side effect of disabling host-name whitelisting (see
27161 @code{rpc-host-whitelist-enabled?}.
27163 Defaults to @samp{#f}.
27167 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
27168 The username required by clients to access the @acronym{RPC} interface
27169 when @code{rpc-authentication-required?} is @code{#t}.
27171 Defaults to @samp{disabled}.
27175 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
27176 The password required by clients to access the @acronym{RPC} interface
27177 when @code{rpc-authentication-required?} is @code{#t}. This must be
27178 specified using a password hash in the format recognized by Transmission
27179 clients, either copied from an existing @file{settings.json} file or
27180 generated using the @code{transmission-password-hash} procedure.
27182 Defaults to @samp{disabled}.
27186 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
27187 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27188 originate from an address specified in @code{rpc-whitelist}.
27190 Defaults to @samp{#t}.
27194 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
27195 The list of IP and IPv6 addresses from which @acronym{RPC} requests will
27196 be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
27197 may be specified using @samp{*}.
27199 Defaults to @samp{("127.0.0.1" "::1")}.
27203 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
27204 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27205 are addressed to a host named in @code{rpc-host-whitelist}. Note that
27206 requests to ``localhost'' or ``localhost.'', or to a numeric address,
27207 are always accepted regardless of these settings.
27209 Note also this functionality is disabled when
27210 @code{rpc-authentication-required?} is @code{#t}.
27212 Defaults to @samp{#t}.
27216 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
27217 The list of host names recognized by the @acronym{RPC} server when
27218 @code{rpc-host-whitelist-enabled?} is @code{#t}.
27220 Defaults to @samp{()}.
27224 @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
27225 The minimum severity level of messages to be logged (to
27226 @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
27227 logging), @code{error}, @code{info} and @code{debug}.
27229 Defaults to @samp{info}.
27233 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
27234 When @code{#t}, torrents are started as soon as they are added;
27235 otherwise, they are added in ``paused'' state.
27237 Defaults to @samp{#t}.
27241 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
27242 When @code{#t}, the script specified by
27243 @code{script-torrent-done-filename} will be invoked each time a torrent
27246 Defaults to @samp{#f}.
27250 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
27251 A file name or file-like object specifying a script to run each time a
27252 torrent completes, when @code{script-torrent-done-enabled?} is
27255 Defaults to @samp{disabled}.
27259 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
27260 When @code{#t}, the daemon will scrape trackers for a torrent even when
27261 the torrent is paused.
27263 Defaults to @samp{#t}.
27267 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
27268 The amount of memory, in megabytes, to allocate for the daemon's
27269 in-memory cache. A larger value may increase performance by reducing
27270 the frequency of disk I/O.
27272 Defaults to @samp{4}.
27276 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
27277 When @code{#t}, the daemon will try to improve I/O performance by
27278 hinting to the operating system which data is likely to be read next
27279 from disk to satisfy requests from peers.
27281 Defaults to @samp{#t}.
27286 @c %end of fragment
27290 @node Monitoring Services
27291 @subsection Monitoring Services
27293 @subsubheading Tailon Service
27295 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
27296 viewing and searching log files.
27298 The following example will configure the service with default values.
27299 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
27302 (service tailon-service-type)
27305 The following example customises more of the Tailon configuration,
27306 adding @command{sed} to the list of allowed commands.
27309 (service tailon-service-type
27310 (tailon-configuration
27312 (tailon-configuration-file
27313 (allowed-commands '("tail" "grep" "awk" "sed"))))))
27317 @deftp {Data Type} tailon-configuration
27318 Data type representing the configuration of Tailon.
27319 This type has the following parameters:
27322 @item @code{config-file} (default: @code{(tailon-configuration-file)})
27323 The configuration file to use for Tailon. This can be set to a
27324 @dfn{tailon-configuration-file} record value, or any gexp
27325 (@pxref{G-Expressions}).
27327 For example, to instead use a local file, the @code{local-file} function
27331 (service tailon-service-type
27332 (tailon-configuration
27333 (config-file (local-file "./my-tailon.conf"))))
27336 @item @code{package} (default: @code{tailon})
27337 The tailon package to use.
27342 @deftp {Data Type} tailon-configuration-file
27343 Data type representing the configuration options for Tailon.
27344 This type has the following parameters:
27347 @item @code{files} (default: @code{(list "/var/log")})
27348 List of files to display. The list can include strings for a single file
27349 or directory, or a list, where the first item is the name of a
27350 subsection, and the remaining items are the files or directories in that
27353 @item @code{bind} (default: @code{"localhost:8080"})
27354 Address and port to which Tailon should bind on.
27356 @item @code{relative-root} (default: @code{#f})
27357 URL path to use for Tailon, set to @code{#f} to not use a path.
27359 @item @code{allow-transfers?} (default: @code{#t})
27360 Allow downloading the log files in the web interface.
27362 @item @code{follow-names?} (default: @code{#t})
27363 Allow tailing of not-yet existent files.
27365 @item @code{tail-lines} (default: @code{200})
27366 Number of lines to read initially from each file.
27368 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
27369 Commands to allow running. By default, @code{sed} is disabled.
27371 @item @code{debug?} (default: @code{#f})
27372 Set @code{debug?} to @code{#t} to show debug messages.
27374 @item @code{wrap-lines} (default: @code{#t})
27375 Initial line wrapping state in the web interface. Set to @code{#t} to
27376 initially wrap lines (the default), or to @code{#f} to initially not
27379 @item @code{http-auth} (default: @code{#f})
27380 HTTP authentication type to use. Set to @code{#f} to disable
27381 authentication (the default). Supported values are @code{"digest"} or
27384 @item @code{users} (default: @code{#f})
27385 If HTTP authentication is enabled (see @code{http-auth}), access will be
27386 restricted to the credentials provided here. To configure users, use a
27387 list of pairs, where the first element of the pair is the username, and
27388 the 2nd element of the pair is the password.
27391 (tailon-configuration-file
27392 (http-auth "basic")
27393 (users '(("user1" . "password1")
27394 ("user2" . "password2"))))
27401 @subsubheading Darkstat Service
27403 Darkstat is a packet sniffer that captures network traffic, calculates
27404 statistics about usage, and serves reports over HTTP.
27406 @defvar {Scheme Variable} darkstat-service-type
27407 This is the service type for the
27408 @uref{https://unix4lyfe.org/darkstat/, darkstat}
27409 service, its value must be a @code{darkstat-configuration} record as in
27413 (service darkstat-service-type
27414 (darkstat-configuration
27415 (interface "eno1")))
27419 @deftp {Data Type} darkstat-configuration
27420 Data type representing the configuration of @command{darkstat}.
27423 @item @code{package} (default: @code{darkstat})
27424 The darkstat package to use.
27426 @item @code{interface}
27427 Capture traffic on the specified network interface.
27429 @item @code{port} (default: @code{"667"})
27430 Bind the web interface to the specified port.
27432 @item @code{bind-address} (default: @code{"127.0.0.1"})
27433 Bind the web interface to the specified address.
27435 @item @code{base} (default: @code{"/"})
27436 Specify the path of the base URL@. This can be useful if
27437 @command{darkstat} is accessed via a reverse proxy.
27442 @anchor{prometheus-node-exporter}
27443 @subsubheading Prometheus Node Exporter Service
27444 @cindex prometheus-node-exporter
27446 The Prometheus ``node exporter'' makes hardware and operating system statistics
27447 provided by the Linux kernel available for the Prometheus monitoring system.
27448 This service should be deployed on all physical nodes and virtual machines,
27449 where monitoring these statistics is desirable.
27451 @defvar {Scheme variable} prometheus-node-exporter-service-type
27452 This is the service type for the
27453 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
27454 service, its value must be a @code{prometheus-node-exporter-configuration}.
27457 (service prometheus-node-exporter-service-type)
27461 @deftp {Data Type} prometheus-node-exporter-configuration
27462 Data type representing the configuration of @command{node_exporter}.
27465 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
27466 The prometheus-node-exporter package to use.
27468 @item @code{web-listen-address} (default: @code{":9100"})
27469 Bind the web interface to the specified address.
27471 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
27472 This directory can be used to export metrics specific to this machine.
27473 Files containing metrics in the text format, with the filename ending in
27474 @code{.prom} should be placed in this directory.
27476 @item @code{extra-options} (default: @code{'()})
27477 Extra options to pass to the Prometheus node exporter.
27482 @subsubheading Zabbix server
27483 @cindex zabbix zabbix-server
27484 Zabbix is a high performance monitoring system that can collect data from a
27485 variety of sources and provide the results in a web-based interface. Alerting
27486 and reporting is built-in, as well as @dfn{templates} for common operating
27487 system metrics such as network utilization, CPU load, and disk space consumption.
27489 This service provides the central Zabbix monitoring service; you also need
27490 @ref{zabbix-front-end,@code{zabbix-front-end-service-type}} to configure Zabbix
27491 and display results, and optionally @ref{zabbix-agent,
27492 @code{zabbix-agent-service-type}} on machines that should be monitored (other
27493 data sources are supported, such as @ref{prometheus-node-exporter,
27494 Prometheus Node Exporter}).
27496 @defvar {Scheme variable} zabbix-server-service-type
27497 This is the service type for the Zabbix server service. Its value must be a
27498 @code{zabbix-server-configuration} record, shown below.
27501 @c %start of fragment
27503 @deftp {Data Type} zabbix-server-configuration
27504 Available @code{zabbix-server-configuration} fields are:
27507 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27508 The zabbix-server package.
27510 @item @code{user} (default: @code{"zabbix"}) (type: string)
27511 User who will run the Zabbix server.
27513 @item @code{group} (default: @code{"zabbix"}) (type: group)
27514 Group who will run the Zabbix server.
27516 @item @code{db-host} (default: @code{"127.0.0.1"}) (type: string)
27517 Database host name.
27519 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27522 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27525 @item @code{db-password} (default: @code{""}) (type: string)
27526 Database password. Please, use @code{include-files} with
27527 @code{DBPassword=SECRET} inside a specified file instead.
27529 @item @code{db-port} (default: @code{5432}) (type: number)
27532 @item @code{log-type} (default: @code{""}) (type: string)
27533 Specifies where log messages are written to:
27537 @item @code{system} - syslog.
27539 @item @code{file} - file specified with @code{log-file} parameter.
27541 @item @code{console} - standard output.
27545 @item @code{log-file} (default: @code{"/var/log/zabbix/server.log"}) (type: string)
27546 Log file name for @code{log-type} @code{file} parameter.
27548 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_server.pid"}) (type: string)
27551 @item @code{ssl-ca-location} (default: @code{"/etc/ssl/certs/ca-certificates.crt"}) (type: string)
27552 The location of certificate authority (CA) files for SSL server
27553 certificate verification.
27555 @item @code{ssl-cert-location} (default: @code{"/etc/ssl/certs"}) (type: string)
27556 Location of SSL client certificates.
27558 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27559 Extra options will be appended to Zabbix server configuration file.
27561 @item @code{include-files} (default: @code{()}) (type: include-files)
27562 You may include individual files or all files in a directory in the
27563 configuration file.
27570 @c %end of fragment
27572 @anchor{zabbix-agent}
27573 @subsubheading Zabbix agent
27574 @cindex zabbix zabbix-agent
27576 The Zabbix agent gathers information about the running system for the Zabbix
27577 monitoring server. It has a variety of built-in checks, and can be extended
27579 @uref{https://www.zabbix.com/documentation/current/en/manual/config/items/userparameters,
27580 @dfn{user parameters}}.
27582 @defvar {Scheme variable} zabbix-agent-service-type
27583 This is the service type for the Zabbix agent service. Its value must be a
27584 @code{zabbix-agent-configuration} record, shown below.
27587 @c %start of fragment
27589 @deftp {Data Type} zabbix-agent-configuration
27590 Available @code{zabbix-agent-configuration} fields are:
27593 @item @code{zabbix-agent} (default: @code{zabbix-agentd}) (type: file-like)
27594 The zabbix-agent package.
27596 @item @code{user} (default: @code{"zabbix"}) (type: string)
27597 User who will run the Zabbix agent.
27599 @item @code{group} (default: @code{"zabbix"}) (type: group)
27600 Group who will run the Zabbix agent.
27602 @item @code{hostname} (default: @code{""}) (type: string)
27603 Unique, case sensitive hostname which is required for active checks and
27604 must match hostname as configured on the server.
27606 @item @code{log-type} (default: @code{""}) (type: string)
27607 Specifies where log messages are written to:
27611 @code{system} - syslog.
27613 @item @code{file} - file specified with
27614 @code{log-file} parameter.
27616 @item @code{console} - standard output.
27620 @item @code{log-file} (default: @code{"/var/log/zabbix/agent.log"}) (type: string)
27621 Log file name for @code{log-type} @code{file} parameter.
27623 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_agent.pid"}) (type: string)
27626 @item @code{server} (default: @code{("127.0.0.1")}) (type: list)
27627 List of IP addresses, optionally in CIDR notation, or hostnames of
27628 Zabbix servers and Zabbix proxies. Incoming connections will be
27629 accepted only from the hosts listed here.
27631 @item @code{server-active} (default: @code{("127.0.0.1")}) (type: list)
27632 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
27633 proxies for active checks. If port is not specified, default port is
27634 used. If this parameter is not specified, active checks are disabled.
27636 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27637 Extra options will be appended to Zabbix server configuration file.
27639 @item @code{include-files} (default: @code{()}) (type: include-files)
27640 You may include individual files or all files in a directory in the
27641 configuration file.
27648 @c %end of fragment
27650 @anchor{zabbix-front-end}
27651 @subsubheading Zabbix front-end
27652 @cindex zabbix zabbix-front-end
27654 The Zabbix front-end provides a web interface to Zabbix. It does not need
27655 to run on the same machine as the Zabbix server. This service works by
27656 extending the @ref{PHP-FPM} and @ref{NGINX} services with the configuration
27657 necessary for loading the Zabbix user interface.
27659 @defvar {Scheme variable} zabbix-front-end-service-type
27660 This is the service type for the Zabbix web frontend. Its value must be a
27661 @code{zabbix-front-end-configuration} record, shown below.
27664 @c %start of fragment
27666 @deftp {Data Type} zabbix-front-end-configuration
27667 Available @code{zabbix-front-end-configuration} fields are:
27670 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27671 The Zabbix server package to use.
27673 @item @code{nginx} (default: @code{()}) (type: list)
27674 List of @ref{nginx-server-configuration,@code{nginx-server-configuration}}
27675 blocks for the Zabbix front-end. When empty, a default that listens on
27678 @item @code{db-host} (default: @code{"localhost"}) (type: string)
27679 Database host name.
27681 @item @code{db-port} (default: @code{5432}) (type: number)
27684 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27687 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27690 @item @code{db-password} (default: @code{""}) (type: string)
27691 Database password. Please, use @code{db-secret-file} instead.
27693 @item @code{db-secret-file} (default: @code{""}) (type: string)
27694 Secret file which will be appended to @file{zabbix.conf.php} file. This
27695 file contains credentials for use by Zabbix front-end. You are expected
27696 to create it manually.
27698 @item @code{zabbix-host} (default: @code{"localhost"}) (type: string)
27699 Zabbix server hostname.
27701 @item @code{zabbix-port} (default: @code{10051}) (type: number)
27702 Zabbix server port.
27709 @c %end of fragment
27711 @node Kerberos Services
27712 @subsection Kerberos Services
27715 The @code{(gnu services kerberos)} module provides services relating to
27716 the authentication protocol @dfn{Kerberos}.
27718 @subsubheading Krb5 Service
27720 Programs using a Kerberos client library normally
27721 expect a configuration file in @file{/etc/krb5.conf}.
27722 This service generates such a file from a definition provided in the
27723 operating system declaration.
27724 It does not cause any daemon to be started.
27726 No ``keytab'' files are provided by this service---you must explicitly create them.
27727 This service is known to work with the MIT client library, @code{mit-krb5}.
27728 Other implementations have not been tested.
27730 @defvr {Scheme Variable} krb5-service-type
27731 A service type for Kerberos 5 clients.
27735 Here is an example of its use:
27737 (service krb5-service-type
27738 (krb5-configuration
27739 (default-realm "EXAMPLE.COM")
27740 (allow-weak-crypto? #t)
27743 (name "EXAMPLE.COM")
27744 (admin-server "groucho.example.com")
27745 (kdc "karl.example.com"))
27748 (admin-server "kerb-admin.argrx.edu")
27749 (kdc "keys.argrx.edu"))))))
27753 This example provides a Kerberos@tie{}5 client configuration which:
27755 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
27756 of which have distinct administration servers and key distribution centers;
27757 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
27758 specified by clients;
27759 @item Accepts services which only support encryption types known to be weak.
27762 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
27763 Only the most commonly used ones are described here.
27764 For a full list, and more detailed explanation of each, see the MIT
27765 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
27769 @deftp {Data Type} krb5-realm
27770 @cindex realm, kerberos
27773 This field is a string identifying the name of the realm.
27774 A common convention is to use the fully qualified DNS name of your organization,
27775 converted to upper case.
27777 @item @code{admin-server}
27778 This field is a string identifying the host where the administration server is
27782 This field is a string identifying the key distribution center
27787 @deftp {Data Type} krb5-configuration
27790 @item @code{allow-weak-crypto?} (default: @code{#f})
27791 If this flag is @code{#t} then services which only offer encryption algorithms
27792 known to be weak will be accepted.
27794 @item @code{default-realm} (default: @code{#f})
27795 This field should be a string identifying the default Kerberos
27796 realm for the client.
27797 You should set this field to the name of your Kerberos realm.
27798 If this value is @code{#f}
27799 then a realm must be specified with every Kerberos principal when invoking programs
27800 such as @command{kinit}.
27802 @item @code{realms}
27803 This should be a non-empty list of @code{krb5-realm} objects, which clients may
27805 Normally, one of them will have a @code{name} field matching the @code{default-realm}
27811 @subsubheading PAM krb5 Service
27814 The @code{pam-krb5} service allows for login authentication and password
27815 management via Kerberos.
27816 You will need this service if you want PAM enabled applications to authenticate
27817 users using Kerberos.
27819 @defvr {Scheme Variable} pam-krb5-service-type
27820 A service type for the Kerberos 5 PAM module.
27823 @deftp {Data Type} pam-krb5-configuration
27824 Data type representing the configuration of the Kerberos 5 PAM module.
27825 This type has the following parameters:
27827 @item @code{pam-krb5} (default: @code{pam-krb5})
27828 The pam-krb5 package to use.
27830 @item @code{minimum-uid} (default: @code{1000})
27831 The smallest user ID for which Kerberos authentications should be attempted.
27832 Local accounts with lower values will silently fail to authenticate.
27837 @node LDAP Services
27838 @subsection LDAP Services
27840 @cindex nslcd, LDAP service
27842 The @code{(gnu services authentication)} module provides the
27843 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
27844 server. In addition to configuring the service itself, you may want to add
27845 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
27846 Switch} for detailed information.
27848 Here is a simple operating system declaration with a default configuration of
27849 the @code{nslcd-service-type} and a Name Service Switch configuration that
27850 consults the @code{ldap} name service last:
27853 (use-service-modules authentication)
27854 (use-modules (gnu system nss))
27860 (service nslcd-service-type)
27861 (service dhcp-client-service-type)
27863 (name-service-switch
27864 (let ((services (list (name-service (name "db"))
27865 (name-service (name "files"))
27866 (name-service (name "ldap")))))
27867 (name-service-switch
27868 (inherit %mdns-host-lookup-nss)
27869 (password services)
27872 (netgroup services)
27873 (gshadow services)))))
27876 @c %start of generated documentation for nslcd-configuration
27878 Available @code{nslcd-configuration} fields are:
27880 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
27881 The @code{nss-pam-ldapd} package to use.
27885 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
27886 The number of threads to start that can handle requests and perform LDAP
27887 queries. Each thread opens a separate connection to the LDAP server.
27888 The default is to start 5 threads.
27890 Defaults to @samp{disabled}.
27894 @deftypevr {@code{nslcd-configuration} parameter} string uid
27895 This specifies the user id with which the daemon should be run.
27897 Defaults to @samp{"nslcd"}.
27901 @deftypevr {@code{nslcd-configuration} parameter} string gid
27902 This specifies the group id with which the daemon should be run.
27904 Defaults to @samp{"nslcd"}.
27908 @deftypevr {@code{nslcd-configuration} parameter} log-option log
27909 This option controls the way logging is done via a list containing
27910 SCHEME and LEVEL@. The SCHEME argument may either be the symbols
27911 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
27912 argument is optional and specifies the log level. The log level may be
27913 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
27914 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
27915 specified log level or higher are logged.
27917 Defaults to @samp{("/var/log/nslcd" info)}.
27921 @deftypevr {@code{nslcd-configuration} parameter} list uri
27922 The list of LDAP server URIs. Normally, only the first server will be
27923 used with the following servers as fall-back.
27925 Defaults to @samp{("ldap://localhost:389/")}.
27929 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
27930 The version of the LDAP protocol to use. The default is to use the
27931 maximum version supported by the LDAP library.
27933 Defaults to @samp{disabled}.
27937 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
27938 Specifies the distinguished name with which to bind to the directory
27939 server for lookups. The default is to bind anonymously.
27941 Defaults to @samp{disabled}.
27945 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
27946 Specifies the credentials with which to bind. This option is only
27947 applicable when used with binddn.
27949 Defaults to @samp{disabled}.
27953 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
27954 Specifies the distinguished name to use when the root user tries to
27955 modify a user's password using the PAM module.
27957 Defaults to @samp{disabled}.
27961 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
27962 Specifies the credentials with which to bind if the root user tries to
27963 change a user's password. This option is only applicable when used with
27966 Defaults to @samp{disabled}.
27970 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
27971 Specifies the SASL mechanism to be used when performing SASL
27974 Defaults to @samp{disabled}.
27978 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
27979 Specifies the SASL realm to be used when performing SASL authentication.
27981 Defaults to @samp{disabled}.
27985 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
27986 Specifies the authentication identity to be used when performing SASL
27989 Defaults to @samp{disabled}.
27993 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
27994 Specifies the authorization identity to be used when performing SASL
27997 Defaults to @samp{disabled}.
28001 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
28002 Determines whether the LDAP server host name should be canonicalised. If
28003 this is enabled the LDAP library will do a reverse host name lookup. By
28004 default, it is left up to the LDAP library whether this check is
28007 Defaults to @samp{disabled}.
28011 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
28012 Set the name for the GSS-API Kerberos credentials cache.
28014 Defaults to @samp{disabled}.
28018 @deftypevr {@code{nslcd-configuration} parameter} string base
28019 The directory search base.
28021 Defaults to @samp{"dc=example,dc=com"}.
28025 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
28026 Specifies the search scope (subtree, onelevel, base or children). The
28027 default scope is subtree; base scope is almost never useful for name
28028 service lookups; children scope is not supported on all servers.
28030 Defaults to @samp{(subtree)}.
28034 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
28035 Specifies the policy for dereferencing aliases. The default policy is
28036 to never dereference aliases.
28038 Defaults to @samp{disabled}.
28042 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
28043 Specifies whether automatic referral chasing should be enabled. The
28044 default behaviour is to chase referrals.
28046 Defaults to @samp{disabled}.
28050 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
28051 This option allows for custom attributes to be looked up instead of the
28052 default RFC 2307 attributes. It is a list of maps, each consisting of
28053 the name of a map, the RFC 2307 attribute to match and the query
28054 expression for the attribute as it is available in the directory.
28056 Defaults to @samp{()}.
28060 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
28061 A list of filters consisting of the name of a map to which the filter
28062 applies and an LDAP search filter expression.
28064 Defaults to @samp{()}.
28068 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
28069 Specifies the time limit in seconds to use when connecting to the
28070 directory server. The default value is 10 seconds.
28072 Defaults to @samp{disabled}.
28076 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
28077 Specifies the time limit (in seconds) to wait for a response from the
28078 LDAP server. A value of zero, which is the default, is to wait
28079 indefinitely for searches to be completed.
28081 Defaults to @samp{disabled}.
28085 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
28086 Specifies the period if inactivity (in seconds) after which the con‐
28087 nection to the LDAP server will be closed. The default is not to time
28090 Defaults to @samp{disabled}.
28094 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
28095 Specifies the number of seconds to sleep when connecting to all LDAP
28096 servers fails. By default one second is waited between the first
28097 failure and the first retry.
28099 Defaults to @samp{disabled}.
28103 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
28104 Specifies the time after which the LDAP server is considered to be
28105 permanently unavailable. Once this time is reached retries will be done
28106 only once per this time period. The default value is 10 seconds.
28108 Defaults to @samp{disabled}.
28112 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
28113 Specifies whether to use SSL/TLS or not (the default is not to). If
28114 'start-tls is specified then StartTLS is used rather than raw LDAP over
28117 Defaults to @samp{disabled}.
28121 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
28122 Specifies what checks to perform on a server-supplied certificate. The
28123 meaning of the values is described in the ldap.conf(5) manual page.
28125 Defaults to @samp{disabled}.
28129 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
28130 Specifies the directory containing X.509 certificates for peer authen‐
28131 tication. This parameter is ignored when using GnuTLS.
28133 Defaults to @samp{disabled}.
28137 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
28138 Specifies the path to the X.509 certificate for peer authentication.
28140 Defaults to @samp{disabled}.
28144 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
28145 Specifies the path to an entropy source. This parameter is ignored when
28148 Defaults to @samp{disabled}.
28152 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
28153 Specifies the ciphers to use for TLS as a string.
28155 Defaults to @samp{disabled}.
28159 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
28160 Specifies the path to the file containing the local certificate for
28161 client TLS authentication.
28163 Defaults to @samp{disabled}.
28167 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
28168 Specifies the path to the file containing the private key for client TLS
28171 Defaults to @samp{disabled}.
28175 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
28176 Set this to a number greater than 0 to request paged results from the
28177 LDAP server in accordance with RFC2696. The default (0) is to not
28178 request paged results.
28180 Defaults to @samp{disabled}.
28184 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
28185 This option prevents group membership lookups through LDAP for the
28186 specified users. Alternatively, the value 'all-local may be used. With
28187 that value nslcd builds a full list of non-LDAP users on startup.
28189 Defaults to @samp{disabled}.
28193 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
28194 This option ensures that LDAP users with a numeric user id lower than
28195 the specified value are ignored.
28197 Defaults to @samp{disabled}.
28201 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
28202 This option specifies an offset that is added to all LDAP numeric user
28203 ids. This can be used to avoid user id collisions with local users.
28205 Defaults to @samp{disabled}.
28209 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
28210 This option specifies an offset that is added to all LDAP numeric group
28211 ids. This can be used to avoid user id collisions with local groups.
28213 Defaults to @samp{disabled}.
28217 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
28218 If this option is set, the member attribute of a group may point to
28219 another group. Members of nested groups are also returned in the higher
28220 level group and parent groups are returned when finding groups for a
28221 specific user. The default is not to perform extra searches for nested
28224 Defaults to @samp{disabled}.
28228 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
28229 If this option is set, the group member list is not retrieved when
28230 looking up groups. Lookups for finding which groups a user belongs to
28231 will remain functional so the user will likely still get the correct
28232 groups assigned on login.
28234 Defaults to @samp{disabled}.
28238 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
28239 If this option is set, functions which cause all user/group entries to
28240 be loaded from the directory will not succeed in doing so. This can
28241 dramatically reduce LDAP server load in situations where there are a
28242 great number of users and/or groups. This option is not recommended for
28243 most configurations.
28245 Defaults to @samp{disabled}.
28249 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
28250 This option can be used to specify how user and group names are verified
28251 within the system. This pattern is used to check all user and group
28252 names that are requested and returned from LDAP.
28254 Defaults to @samp{disabled}.
28258 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
28259 This specifies whether or not to perform searches using case-insensitive
28260 matching. Enabling this could open up the system to authorization
28261 bypass vulnerabilities and introduce nscd cache poisoning
28262 vulnerabilities which allow denial of service.
28264 Defaults to @samp{disabled}.
28268 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
28269 This option specifies whether password policy controls are requested and
28270 handled from the LDAP server when performing user authentication.
28272 Defaults to @samp{disabled}.
28276 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
28277 By default nslcd performs an LDAP search with the user's credentials
28278 after BIND (authentication) to ensure that the BIND operation was
28279 successful. The default search is a simple check to see if the user's
28280 DN exists. A search filter can be specified that will be used instead.
28281 It should return at least one entry.
28283 Defaults to @samp{disabled}.
28287 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
28288 This option allows flexible fine tuning of the authorisation check that
28289 should be performed. The search filter specified is executed and if any
28290 entries match, access is granted, otherwise access is denied.
28292 Defaults to @samp{disabled}.
28296 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
28297 If this option is set password modification using pam_ldap will be
28298 denied and the specified message will be presented to the user instead.
28299 The message can be used to direct the user to an alternative means of
28300 changing their password.
28302 Defaults to @samp{disabled}.
28306 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
28307 List of pam service names for which LDAP authentication should suffice.
28309 Defaults to @samp{()}.
28313 @c %end of generated documentation for nslcd-configuration
28317 @subsection Web Services
28322 The @code{(gnu services web)} module provides the Apache HTTP Server,
28323 the nginx web server, and also a fastcgi wrapper daemon.
28325 @subsubheading Apache HTTP Server
28327 @deffn {Scheme Variable} httpd-service-type
28328 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
28329 (@dfn{httpd}). The value for this service type is a
28330 @code{httpd-configuration} record.
28332 A simple example configuration is given below.
28335 (service httpd-service-type
28336 (httpd-configuration
28339 (server-name "www.example.com")
28340 (document-root "/srv/http/www.example.com")))))
28343 Other services can also extend the @code{httpd-service-type} to add to
28347 (simple-service 'www.example.com-server httpd-service-type
28351 (list (string-join '("ServerName www.example.com"
28352 "DocumentRoot /srv/http/www.example.com")
28357 The details for the @code{httpd-configuration}, @code{httpd-module},
28358 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
28361 @deffn {Data Type} httpd-configuration
28362 This data type represents the configuration for the httpd service.
28365 @item @code{package} (default: @code{httpd})
28366 The httpd package to use.
28368 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28369 The pid file used by the shepherd-service.
28371 @item @code{config} (default: @code{(httpd-config-file)})
28372 The configuration file to use with the httpd service. The default value
28373 is a @code{httpd-config-file} record, but this can also be a different
28374 G-expression that generates a file, for example a @code{plain-file}. A
28375 file outside of the store can also be specified through a string.
28380 @deffn {Data Type} httpd-module
28381 This data type represents a module for the httpd service.
28385 The name of the module.
28388 The file for the module. This can be relative to the httpd package being
28389 used, the absolute location of a file, or a G-expression for a file
28390 within the store, for example @code{(file-append mod-wsgi
28391 "/modules/mod_wsgi.so")}.
28396 @defvr {Scheme Variable} %default-httpd-modules
28397 A default list of @code{httpd-module} objects.
28400 @deffn {Data Type} httpd-config-file
28401 This data type represents a configuration file for the httpd service.
28404 @item @code{modules} (default: @code{%default-httpd-modules})
28405 The modules to load. Additional modules can be added here, or loaded by
28406 additional configuration.
28408 For example, in order to handle requests for PHP files, you can use Apache’s
28409 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
28412 (service httpd-service-type
28413 (httpd-configuration
28418 (name "proxy_module")
28419 (file "modules/mod_proxy.so"))
28421 (name "proxy_fcgi_module")
28422 (file "modules/mod_proxy_fcgi.so"))
28423 %default-httpd-modules))
28424 (extra-config (list "\
28425 <FilesMatch \\.php$>
28426 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
28427 </FilesMatch>"))))))
28428 (service php-fpm-service-type
28429 (php-fpm-configuration
28430 (socket "/var/run/php-fpm.sock")
28431 (socket-group "httpd")))
28434 @item @code{server-root} (default: @code{httpd})
28435 The @code{ServerRoot} in the configuration file, defaults to the httpd
28436 package. Directives including @code{Include} and @code{LoadModule} are
28437 taken as relative to the server root.
28439 @item @code{server-name} (default: @code{#f})
28440 The @code{ServerName} in the configuration file, used to specify the
28441 request scheme, hostname and port that the server uses to identify
28444 This doesn't need to be set in the server config, and can be specified
28445 in virtual hosts. The default is @code{#f} to not specify a
28448 @item @code{document-root} (default: @code{"/srv/http"})
28449 The @code{DocumentRoot} from which files will be served.
28451 @item @code{listen} (default: @code{'("80")})
28452 The list of values for the @code{Listen} directives in the config
28453 file. The value should be a list of strings, when each string can
28454 specify the port number to listen on, and optionally the IP address and
28457 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28458 The @code{PidFile} to use. This should match the @code{pid-file} set in
28459 the @code{httpd-configuration} so that the Shepherd service is
28460 configured correctly.
28462 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
28463 The @code{ErrorLog} to which the server will log errors.
28465 @item @code{user} (default: @code{"httpd"})
28466 The @code{User} which the server will answer requests as.
28468 @item @code{group} (default: @code{"httpd"})
28469 The @code{Group} which the server will answer requests as.
28471 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
28472 A flat list of strings and G-expressions which will be added to the end
28473 of the configuration file.
28475 Any values which the service is extended with will be appended to this
28481 @deffn {Data Type} httpd-virtualhost
28482 This data type represents a virtualhost configuration block for the httpd service.
28484 These should be added to the extra-config for the httpd-service.
28487 (simple-service 'www.example.com-server httpd-service-type
28491 (list (string-join '("ServerName www.example.com"
28492 "DocumentRoot /srv/http/www.example.com")
28497 @item @code{addresses-and-ports}
28498 The addresses and ports for the @code{VirtualHost} directive.
28500 @item @code{contents}
28501 The contents of the @code{VirtualHost} directive, this should be a list
28502 of strings and G-expressions.
28508 @subsubheading NGINX
28510 @deffn {Scheme Variable} nginx-service-type
28511 Service type for the @uref{https://nginx.org/,NGinx} web server. The
28512 value for this service type is a @code{<nginx-configuration>} record.
28514 A simple example configuration is given below.
28517 (service nginx-service-type
28518 (nginx-configuration
28520 (list (nginx-server-configuration
28521 (server-name '("www.example.com"))
28522 (root "/srv/http/www.example.com"))))))
28525 In addition to adding server blocks to the service configuration
28526 directly, this service can be extended by other services to add server
28527 blocks, as in this example:
28530 (simple-service 'my-extra-server nginx-service-type
28531 (list (nginx-server-configuration
28532 (root "/srv/http/extra-website")
28533 (try-files (list "$uri" "$uri/index.html")))))
28537 At startup, @command{nginx} has not yet read its configuration file, so
28538 it uses a default file to log error messages. If it fails to load its
28539 configuration file, that is where error messages are logged. After the
28540 configuration file is loaded, the default error log file changes as per
28541 configuration. In our case, startup error messages can be found in
28542 @file{/var/run/nginx/logs/error.log}, and after configuration in
28543 @file{/var/log/nginx/error.log}. The second location can be changed
28544 with the @var{log-directory} configuration option.
28546 @deffn {Data Type} nginx-configuration
28547 This data type represents the configuration for NGinx. Some
28548 configuration can be done through this and the other provided record
28549 types, or alternatively, a config file can be provided.
28552 @item @code{nginx} (default: @code{nginx})
28553 The nginx package to use.
28555 @item @code{log-directory} (default: @code{"/var/log/nginx"})
28556 The directory to which NGinx will write log files.
28558 @item @code{run-directory} (default: @code{"/var/run/nginx"})
28559 The directory in which NGinx will create a pid file, and write temporary
28562 @item @code{server-blocks} (default: @code{'()})
28563 A list of @dfn{server blocks} to create in the generated configuration
28564 file, the elements should be of type
28565 @code{<nginx-server-configuration>}.
28567 The following example would setup NGinx to serve @code{www.example.com}
28568 from the @code{/srv/http/www.example.com} directory, without using
28571 (service nginx-service-type
28572 (nginx-configuration
28574 (list (nginx-server-configuration
28575 (server-name '("www.example.com"))
28576 (root "/srv/http/www.example.com"))))))
28579 @item @code{upstream-blocks} (default: @code{'()})
28580 A list of @dfn{upstream blocks} to create in the generated configuration
28581 file, the elements should be of type
28582 @code{<nginx-upstream-configuration>}.
28584 Configuring upstreams through the @code{upstream-blocks} can be useful
28585 when combined with @code{locations} in the
28586 @code{<nginx-server-configuration>} records. The following example
28587 creates a server configuration with one location configuration, that
28588 will proxy requests to a upstream configuration, which will handle
28589 requests with two servers.
28594 (nginx-configuration
28596 (list (nginx-server-configuration
28597 (server-name '("www.example.com"))
28598 (root "/srv/http/www.example.com")
28601 (nginx-location-configuration
28603 (body '("proxy_pass http://server-proxy;"))))))))
28605 (list (nginx-upstream-configuration
28606 (name "server-proxy")
28607 (servers (list "server1.example.com"
28608 "server2.example.com")))))))
28611 @item @code{file} (default: @code{#f})
28612 If a configuration @var{file} is provided, this will be used, rather than
28613 generating a configuration file from the provided @code{log-directory},
28614 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
28615 proper operation, these arguments should match what is in @var{file} to ensure
28616 that the directories are created when the service is activated.
28618 This can be useful if you have an existing configuration file, or it's
28619 not possible to do what is required through the other parts of the
28620 nginx-configuration record.
28622 @item @code{server-names-hash-bucket-size} (default: @code{#f})
28623 Bucket size for the server names hash tables, defaults to @code{#f} to
28624 use the size of the processors cache line.
28626 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
28627 Maximum bucket size for the server names hash tables.
28629 @item @code{modules} (default: @code{'()})
28630 List of nginx dynamic modules to load. This should be a list of file
28631 names of loadable modules, as in this example:
28636 (file-append nginx-accept-language-module "\
28637 /etc/nginx/modules/ngx_http_accept_language_module.so")
28638 (file-append nginx-lua-module "\
28639 /etc/nginx/modules/ngx_http_lua_module.so")))
28642 @item @code{lua-package-path} (default: @code{'()})
28643 List of nginx lua packages to load. This should be a list of package
28644 names of loadable lua modules, as in this example:
28647 (lua-package-path (list lua-resty-core
28654 @item @code{lua-package-cpath} (default: @code{'()})
28655 List of nginx lua C packages to load. This should be a list of package
28656 names of loadable lua C modules, as in this example:
28659 (lua-package-cpath (list lua-resty-signal))
28662 @item @code{global-directives} (default: @code{'((events . ()))})
28663 Association list of global directives for the top level of the nginx
28664 configuration. Values may themselves be association lists.
28668 `((worker_processes . 16)
28670 (events . ((worker_connections . 1024)))))
28673 @item @code{extra-content} (default: @code{""})
28674 Extra content for the @code{http} block. Should be string or a string
28675 valued G-expression.
28680 @anchor{nginx-server-configuration}
28681 @deftp {Data Type} nginx-server-configuration
28682 Data type representing the configuration of an nginx server block.
28683 This type has the following parameters:
28686 @item @code{listen} (default: @code{'("80" "443 ssl")})
28687 Each @code{listen} directive sets the address and port for IP, or the
28688 path for a UNIX-domain socket on which the server will accept requests.
28689 Both address and port, or only address or only port can be specified.
28690 An address may also be a hostname, for example:
28693 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
28696 @item @code{server-name} (default: @code{(list 'default)})
28697 A list of server names this server represents. @code{'default} represents the
28698 default server for connections matching no other server.
28700 @item @code{root} (default: @code{"/srv/http"})
28701 Root of the website nginx will serve.
28703 @item @code{locations} (default: @code{'()})
28704 A list of @dfn{nginx-location-configuration} or
28705 @dfn{nginx-named-location-configuration} records to use within this
28708 @item @code{index} (default: @code{(list "index.html")})
28709 Index files to look for when clients ask for a directory. If it cannot be found,
28710 Nginx will send the list of files in the directory.
28712 @item @code{try-files} (default: @code{'()})
28713 A list of files whose existence is checked in the specified order.
28714 @code{nginx} will use the first file it finds to process the request.
28716 @item @code{ssl-certificate} (default: @code{#f})
28717 Where to find the certificate for secure connections. Set it to @code{#f} if
28718 you don't have a certificate or you don't want to use HTTPS.
28720 @item @code{ssl-certificate-key} (default: @code{#f})
28721 Where to find the private key for secure connections. Set it to @code{#f} if
28722 you don't have a key or you don't want to use HTTPS.
28724 @item @code{server-tokens?} (default: @code{#f})
28725 Whether the server should add its configuration to response.
28727 @item @code{raw-content} (default: @code{'()})
28728 A list of raw lines added to the server block.
28733 @deftp {Data Type} nginx-upstream-configuration
28734 Data type representing the configuration of an nginx @code{upstream}
28735 block. This type has the following parameters:
28739 Name for this group of servers.
28741 @item @code{servers}
28742 Specify the addresses of the servers in the group. The address can be
28743 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
28744 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
28745 prefix @samp{unix:}. For addresses using an IP address or domain name,
28746 the default port is 80, and a different port can be specified
28749 @item @code{extra-content}
28750 A string or list of strings to add to the upstream block.
28755 @deftp {Data Type} nginx-location-configuration
28756 Data type representing the configuration of an nginx @code{location}
28757 block. This type has the following parameters:
28761 URI which this location block matches.
28763 @anchor{nginx-location-configuration body}
28765 Body of the location block, specified as a list of strings. This can contain
28767 configuration directives. For example, to pass requests to a upstream
28768 server group defined using an @code{nginx-upstream-configuration} block,
28769 the following directive would be specified in the body @samp{(list "proxy_pass
28770 http://upstream-name;")}.
28775 @deftp {Data Type} nginx-named-location-configuration
28776 Data type representing the configuration of an nginx named location
28777 block. Named location blocks are used for request redirection, and not
28778 used for regular request processing. This type has the following
28783 Name to identify this location block.
28786 @xref{nginx-location-configuration body}, as the body for named location
28787 blocks can be used in a similar way to the
28788 @code{nginx-location-configuration body}. One restriction is that the
28789 body of a named location block cannot contain location blocks.
28794 @subsubheading Varnish Cache
28796 Varnish is a fast cache server that sits in between web applications
28797 and end users. It proxies requests from clients and caches the
28798 accessed URLs such that multiple requests for the same resource only
28799 creates one request to the back-end.
28801 @defvr {Scheme Variable} varnish-service-type
28802 Service type for the Varnish daemon.
28805 @deftp {Data Type} varnish-configuration
28806 Data type representing the @code{varnish} service configuration.
28807 This type has the following parameters:
28810 @item @code{package} (default: @code{varnish})
28811 The Varnish package to use.
28813 @item @code{name} (default: @code{"default"})
28814 A name for this Varnish instance. Varnish will create a directory in
28815 @file{/var/varnish/} with this name and keep temporary files there. If
28816 the name starts with a forward slash, it is interpreted as an absolute
28819 Pass the @code{-n} argument to other Varnish programs to connect to the
28820 named instance, e.g.@: @command{varnishncsa -n default}.
28822 @item @code{backend} (default: @code{"localhost:8080"})
28823 The backend to use. This option has no effect if @code{vcl} is set.
28825 @item @code{vcl} (default: #f)
28826 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
28827 is @code{#f}, Varnish will proxy @code{backend} using the default
28828 configuration. Otherwise this must be a file-like object with valid
28831 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
28832 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
28833 can do something along these lines:
28836 (define %gnu-mirror
28837 (plain-file "gnu.vcl"
28839 backend gnu @{ .host = \"www.gnu.org\"; @}"))
28843 (services (cons (service varnish-service-type
28844 (varnish-configuration
28846 (vcl %gnu-mirror)))
28850 The configuration of an already running Varnish instance can be inspected
28851 and changed using the @command{varnishadm} program.
28853 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
28854 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
28855 comprehensive documentation on Varnish and its configuration language.
28857 @item @code{listen} (default: @code{'("localhost:80")})
28858 List of addresses Varnish will listen on.
28860 @item @code{storage} (default: @code{'("malloc,128m")})
28861 List of storage backends that will be available in VCL.
28863 @item @code{parameters} (default: @code{'()})
28864 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
28866 @item @code{extra-options} (default: @code{'()})
28867 Additional arguments to pass to the @command{varnishd} process.
28872 @subsubheading Patchwork
28874 Patchwork is a patch tracking system. It can collect patches sent to a
28875 mailing list, and display them in a web interface.
28877 @defvr {Scheme Variable} patchwork-service-type
28878 Service type for Patchwork.
28881 The following example is an example of a minimal service for Patchwork, for
28882 the @code{patchwork.example.com} domain.
28885 (service patchwork-service-type
28886 (patchwork-configuration
28887 (domain "patchwork.example.com")
28889 (patchwork-settings-module
28890 (allowed-hosts (list domain))
28891 (default-from-email "patchwork@@patchwork.example.com")))
28892 (getmail-retriever-config
28893 (getmail-retriever-configuration
28894 (type "SimpleIMAPSSLRetriever")
28895 (server "imap.example.com")
28897 (username "patchwork")
28899 (list (file-append coreutils "/bin/cat")
28900 "/etc/getmail-patchwork-imap-password"))
28902 '((mailboxes . ("Patches"))))))))
28906 There are three records for configuring the Patchwork service. The
28907 @code{<patchwork-configuration>} relates to the configuration for Patchwork
28908 within the HTTPD service.
28910 The @code{settings-module} field within the @code{<patchwork-configuration>}
28911 record can be populated with the @code{<patchwork-settings-module>} record,
28912 which describes a settings module that is generated within the Guix store.
28914 For the @code{database-configuration} field within the
28915 @code{<patchwork-settings-module>}, the
28916 @code{<patchwork-database-configuration>} must be used.
28918 @deftp {Data Type} patchwork-configuration
28919 Data type representing the Patchwork service configuration. This type has the
28920 following parameters:
28923 @item @code{patchwork} (default: @code{patchwork})
28924 The Patchwork package to use.
28926 @item @code{domain}
28927 The domain to use for Patchwork, this is used in the HTTPD service virtual
28930 @item @code{settings-module}
28931 The settings module to use for Patchwork. As a Django application, Patchwork
28932 is configured with a Python module containing the settings. This can either be
28933 an instance of the @code{<patchwork-settings-module>} record, any other record
28934 that represents the settings in the store, or a directory outside of the
28937 @item @code{static-path} (default: @code{"/static/"})
28938 The path under which the HTTPD service should serve the static files.
28940 @item @code{getmail-retriever-config}
28941 The getmail-retriever-configuration record value to use with
28942 Patchwork. Getmail will be configured with this value, the messages will be
28943 delivered to Patchwork.
28948 @deftp {Data Type} patchwork-settings-module
28949 Data type representing a settings module for Patchwork. Some of these
28950 settings relate directly to Patchwork, but others relate to Django, the web
28951 framework used by Patchwork, or the Django Rest Framework library. This type
28952 has the following parameters:
28955 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
28956 The database connection settings used for Patchwork. See the
28957 @code{<patchwork-database-configuration>} record type for more information.
28959 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
28960 Patchwork, as a Django web application uses a secret key for cryptographically
28961 signing values. This file should contain a unique unpredictable value.
28963 If this file does not exist, it will be created and populated with a random
28964 value by the patchwork-setup shepherd service.
28966 This setting relates to Django.
28968 @item @code{allowed-hosts}
28969 A list of valid hosts for this Patchwork service. This should at least include
28970 the domain specified in the @code{<patchwork-configuration>} record.
28972 This is a Django setting.
28974 @item @code{default-from-email}
28975 The email address from which Patchwork should send email by default.
28977 This is a Patchwork setting.
28979 @item @code{static-url} (default: @code{#f})
28980 The URL to use when serving static assets. It can be part of a URL, or a full
28981 URL, but must end in a @code{/}.
28983 If the default value is used, the @code{static-path} value from the
28984 @code{<patchwork-configuration>} record will be used.
28986 This is a Django setting.
28988 @item @code{admins} (default: @code{'()})
28989 Email addresses to send the details of errors that occur. Each value should
28990 be a list containing two elements, the name and then the email address.
28992 This is a Django setting.
28994 @item @code{debug?} (default: @code{#f})
28995 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
28996 messages will be shown.
28998 This is a Django setting.
29000 @item @code{enable-rest-api?} (default: @code{#t})
29001 Whether to enable the Patchwork REST API.
29003 This is a Patchwork setting.
29005 @item @code{enable-xmlrpc?} (default: @code{#t})
29006 Whether to enable the XML RPC API.
29008 This is a Patchwork setting.
29010 @item @code{force-https-links?} (default: @code{#t})
29011 Whether to use HTTPS links on Patchwork pages.
29013 This is a Patchwork setting.
29015 @item @code{extra-settings} (default: @code{""})
29016 Extra code to place at the end of the Patchwork settings module.
29021 @deftp {Data Type} patchwork-database-configuration
29022 Data type representing the database configuration for Patchwork.
29025 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
29026 The database engine to use.
29028 @item @code{name} (default: @code{"patchwork"})
29029 The name of the database to use.
29031 @item @code{user} (default: @code{"httpd"})
29032 The user to connect to the database as.
29034 @item @code{password} (default: @code{""})
29035 The password to use when connecting to the database.
29037 @item @code{host} (default: @code{""})
29038 The host to make the database connection to.
29040 @item @code{port} (default: @code{""})
29041 The port on which to connect to the database.
29046 @subsubheading Mumi
29048 @cindex Mumi, Debbugs Web interface
29049 @cindex Debbugs, Mumi Web interface
29050 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
29051 Web interface to the Debbugs bug tracker, by default for
29052 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
29053 but it also fetches and indexes mail retrieved from Debbugs.
29055 @defvr {Scheme Variable} mumi-service-type
29056 This is the service type for Mumi.
29059 @deftp {Data Type} mumi-configuration
29060 Data type representing the Mumi service configuration. This type has the
29064 @item @code{mumi} (default: @code{mumi})
29065 The Mumi package to use.
29067 @item @code{mailer?} (default: @code{#true})
29068 Whether to enable or disable the mailer component.
29070 @item @code{mumi-configuration-sender}
29071 The email address used as the sender for comments.
29073 @item @code{mumi-configuration-smtp}
29074 A URI to configure the SMTP settings for Mailutils. This could be
29075 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
29076 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
29077 mailutils, GNU@tie{}Mailutils}.
29083 @subsubheading FastCGI
29086 FastCGI is an interface between the front-end and the back-end of a web
29087 service. It is a somewhat legacy facility; new web services should
29088 generally just talk HTTP between the front-end and the back-end.
29089 However there are a number of back-end services such as PHP or the
29090 optimized HTTP Git repository access that use FastCGI, so we have
29091 support for it in Guix.
29093 To use FastCGI, you configure the front-end web server (e.g., nginx) to
29094 dispatch some subset of its requests to the fastcgi backend, which
29095 listens on a local TCP or UNIX socket. There is an intermediary
29096 @code{fcgiwrap} program that sits between the actual backend process and
29097 the web server. The front-end indicates which backend program to run,
29098 passing that information to the @code{fcgiwrap} process.
29100 @defvr {Scheme Variable} fcgiwrap-service-type
29101 A service type for the @code{fcgiwrap} FastCGI proxy.
29104 @deftp {Data Type} fcgiwrap-configuration
29105 Data type representing the configuration of the @code{fcgiwrap} service.
29106 This type has the following parameters:
29108 @item @code{package} (default: @code{fcgiwrap})
29109 The fcgiwrap package to use.
29111 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
29112 The socket on which the @code{fcgiwrap} process should listen, as a
29113 string. Valid @var{socket} values include
29114 @code{unix:@var{/path/to/unix/socket}},
29115 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
29116 @code{tcp6:[@var{ipv6_addr}]:port}.
29118 @item @code{user} (default: @code{fcgiwrap})
29119 @itemx @code{group} (default: @code{fcgiwrap})
29120 The user and group names, as strings, under which to run the
29121 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
29122 the user asks for the specific user or group names @code{fcgiwrap} that
29123 the corresponding user and/or group is present on the system.
29125 It is possible to configure a FastCGI-backed web service to pass HTTP
29126 authentication information from the front-end to the back-end, and to
29127 allow @code{fcgiwrap} to run the back-end process as a corresponding
29128 local user. To enable this capability on the back-end, run
29129 @code{fcgiwrap} as the @code{root} user and group. Note that this
29130 capability also has to be configured on the front-end as well.
29135 @subsubheading PHP-FPM
29137 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
29138 with some additional features useful for sites of any size.
29140 These features include:
29142 @item Adaptive process spawning
29143 @item Basic statistics (similar to Apache's mod_status)
29144 @item Advanced process management with graceful stop/start
29145 @item Ability to start workers with different uid/gid/chroot/environment
29146 and different php.ini (replaces safe_mode)
29147 @item Stdout & stderr logging
29148 @item Emergency restart in case of accidental opcode cache destruction
29149 @item Accelerated upload support
29150 @item Support for a "slowlog"
29151 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
29152 a special function to finish request & flush all data while continuing to do
29153 something time-consuming (video converting, stats processing, etc.)
29155 ...@: and much more.
29157 @defvr {Scheme Variable} php-fpm-service-type
29158 A Service type for @code{php-fpm}.
29161 @deftp {Data Type} php-fpm-configuration
29162 Data Type for php-fpm service configuration.
29164 @item @code{php} (default: @code{php})
29165 The php package to use.
29166 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
29167 The address on which to accept FastCGI requests. Valid syntaxes are:
29169 @item @code{"ip.add.re.ss:port"}
29170 Listen on a TCP socket to a specific address on a specific port.
29171 @item @code{"port"}
29172 Listen on a TCP socket to all addresses on a specific port.
29173 @item @code{"/path/to/unix/socket"}
29174 Listen on a unix socket.
29177 @item @code{user} (default: @code{php-fpm})
29178 User who will own the php worker processes.
29179 @item @code{group} (default: @code{php-fpm})
29180 Group of the worker processes.
29181 @item @code{socket-user} (default: @code{php-fpm})
29182 User who can speak to the php-fpm socket.
29183 @item @code{socket-group} (default: @code{nginx})
29184 Group that can speak to the php-fpm socket.
29185 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
29186 The process id of the php-fpm process is written to this file
29187 once the service has started.
29188 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
29189 Log for the php-fpm master process.
29190 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
29191 Detailed settings for the php-fpm process manager.
29194 @item @code{<php-fpm-dynamic-process-manager-configuration>}
29195 @item @code{<php-fpm-static-process-manager-configuration>}
29196 @item @code{<php-fpm-on-demand-process-manager-configuration>}
29198 @item @code{display-errors} (default @code{#f})
29199 Determines whether php errors and warning should be sent to clients
29200 and displayed in their browsers.
29201 This is useful for local php development, but a security risk for public sites,
29202 as error messages can reveal passwords and personal data.
29203 @item @code{timezone} (default @code{#f})
29204 Specifies @code{php_admin_value[date.timezone]} parameter.
29205 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
29206 This file will log the @code{stderr} outputs of php worker processes.
29207 Can be set to @code{#f} to disable logging.
29208 @item @code{file} (default @code{#f})
29209 An optional override of the whole configuration.
29210 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29211 @item @code{php-ini-file} (default @code{#f})
29212 An optional override of the default php settings.
29213 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
29214 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29216 For local development it is useful to set a higher timeout and memory
29217 limit for spawned php processes. This be accomplished with the
29218 following operating system configuration snippet:
29220 (define %local-php-ini
29221 (plain-file "php.ini"
29223 max_execution_time = 1800"))
29227 (services (cons (service php-fpm-service-type
29228 (php-fpm-configuration
29229 (php-ini-file %local-php-ini)))
29233 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
29234 directives} for comprehensive documentation on the acceptable
29235 @file{php.ini} directives.
29239 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
29240 Data Type for the @code{dynamic} php-fpm process manager. With the
29241 @code{dynamic} process manager, spare worker processes are kept around
29242 based on its configured limits.
29244 @item @code{max-children} (default: @code{5})
29245 Maximum of worker processes.
29246 @item @code{start-servers} (default: @code{2})
29247 How many worker processes should be started on start-up.
29248 @item @code{min-spare-servers} (default: @code{1})
29249 How many spare worker processes should be kept around at minimum.
29250 @item @code{max-spare-servers} (default: @code{3})
29251 How many spare worker processes should be kept around at maximum.
29255 @deftp {Data type} php-fpm-static-process-manager-configuration
29256 Data Type for the @code{static} php-fpm process manager. With the
29257 @code{static} process manager, an unchanging number of worker processes
29260 @item @code{max-children} (default: @code{5})
29261 Maximum of worker processes.
29265 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
29266 Data Type for the @code{on-demand} php-fpm process manager. With the
29267 @code{on-demand} process manager, worker processes are only created as
29270 @item @code{max-children} (default: @code{5})
29271 Maximum of worker processes.
29272 @item @code{process-idle-timeout} (default: @code{10})
29273 The time in seconds after which a process with no requests is killed.
29278 @deffn {Scheme Procedure} nginx-php-location @
29279 [#:nginx-package nginx] @
29280 [socket (string-append "/var/run/php" @
29281 (version-major (package-version php)) @
29283 A helper function to quickly add php to an @code{nginx-server-configuration}.
29286 A simple services setup for nginx with php can look like this:
29288 (services (cons* (service dhcp-client-service-type)
29289 (service php-fpm-service-type)
29290 (service nginx-service-type
29291 (nginx-server-configuration
29292 (server-name '("example.com"))
29293 (root "/srv/http/")
29295 (list (nginx-php-location)))
29297 (ssl-certificate #f)
29298 (ssl-certificate-key #f)))
29302 @cindex cat-avatar-generator
29303 The cat avatar generator is a simple service to demonstrate the use of php-fpm
29304 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
29305 the hash of a user's email address.
29307 @deffn {Scheme Procedure} cat-avatar-generator-service @
29308 [#:cache-dir "/var/cache/cat-avatar-generator"] @
29309 [#:package cat-avatar-generator] @
29310 [#:configuration (nginx-server-configuration)]
29311 Returns an nginx-server-configuration that inherits @code{configuration}. It
29312 extends the nginx configuration to add a server block that serves @code{package},
29313 a version of cat-avatar-generator. During execution, cat-avatar-generator will
29314 be able to use @code{cache-dir} as its cache directory.
29317 A simple setup for cat-avatar-generator can look like this:
29319 (services (cons* (cat-avatar-generator-service
29321 (nginx-server-configuration
29322 (server-name '("example.com"))))
29327 @subsubheading Hpcguix-web
29329 @cindex hpcguix-web
29330 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
29331 program is a customizable web interface to browse Guix packages,
29332 initially designed for users of high-performance computing (HPC)
29335 @defvr {Scheme Variable} hpcguix-web-service-type
29336 The service type for @code{hpcguix-web}.
29339 @deftp {Data Type} hpcguix-web-configuration
29340 Data type for the hpcguix-web service configuration.
29344 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
29345 configuration. The main items available in this spec are:
29348 @item @code{title-prefix} (default: @code{"hpcguix | "})
29349 The page title prefix.
29351 @item @code{guix-command} (default: @code{"guix"})
29352 The @command{guix} command.
29354 @item @code{package-filter-proc} (default: @code{(const #t)})
29355 A procedure specifying how to filter packages that are displayed.
29357 @item @code{package-page-extension-proc} (default: @code{(const '())})
29358 Extension package for @code{hpcguix-web}.
29360 @item @code{menu} (default: @code{'()})
29361 Additional entry in page @code{menu}.
29363 @item @code{channels} (default: @code{%default-channels})
29364 List of channels from which the package list is built (@pxref{Channels}).
29366 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
29367 The expiration time, in seconds, after which the package list is rebuilt from
29368 the latest instances of the given channels.
29371 See the hpcguix-web repository for a
29372 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
29375 @item @code{package} (default: @code{hpcguix-web})
29376 The hpcguix-web package to use.
29378 @item @code{address} (default: @code{"127.0.0.1"})
29379 The IP address to listen to.
29381 @item @code{port} (default: @code{5000})
29382 The port number to listen to.
29386 A typical hpcguix-web service declaration looks like this:
29389 (service hpcguix-web-service-type
29390 (hpcguix-web-configuration
29392 #~(define site-config
29393 (hpcweb-configuration
29394 (title-prefix "Guix-HPC - ")
29395 (menu '(("/about" "ABOUT"))))))))
29399 The hpcguix-web service periodically updates the package list it publishes by
29400 pulling channels from Git. To that end, it needs to access X.509 certificates
29401 so that it can authenticate Git servers when communicating over HTTPS, and it
29402 assumes that @file{/etc/ssl/certs} contains those certificates.
29404 Thus, make sure to add @code{nss-certs} or another certificate package to the
29405 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
29406 more information on X.509 certificates.
29409 @subsubheading gmnisrv
29412 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
29413 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
29415 @deffn {Scheme Variable} gmnisrv-service-type
29416 This is the type of the gmnisrv service, whose value should be a
29417 @code{gmnisrv-configuration} object, as in this example:
29420 (service gmnisrv-service-type
29421 (gmnisrv-configuration
29422 (config-file (local-file "./my-gmnisrv.ini"))))
29426 @deftp {Data Type} gmnisrv-configuration
29427 Data type representing the configuration of gmnisrv.
29430 @item @code{package} (default: @var{gmnisrv})
29431 Package object of the gmnisrv server.
29433 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
29434 File-like object of the gmnisrv configuration file to use. The default
29435 configuration listens on port 1965 and serves files from
29436 @file{/srv/gemini}. Certificates are stored in
29437 @file{/var/lib/gemini/certs}. For more information, run @command{man
29438 gmnisrv} and @command{man gmnisrv.ini}.
29443 @subsubheading Agate
29446 The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
29447 (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
29448 program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
29449 protocol server written in Rust.
29451 @deffn {Scheme Variable} agate-service-type
29452 This is the type of the agate service, whose value should be an
29453 @code{agate-service-type} object, as in this example:
29456 (service agate-service-type
29457 (agate-configuration
29458 (content "/srv/gemini")
29459 (cert "/srv/cert.pem")
29460 (key "/srv/key.rsa")))
29463 The example above represents the minimal tweaking necessary to get Agate
29464 up and running. Specifying the path to the certificate and key is
29465 always necessary, as the Gemini protocol requires TLS by default.
29467 To obtain a certificate and a key, you could, for example, use OpenSSL,
29468 running a command similar to the following example:
29471 openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
29472 -days 3650 -nodes -subj "/CN=example.com"
29475 Of course, you'll have to replace @i{example.com} with your own domain
29476 name, and then point the Agate configuration towards the path of the
29477 generated key and certificate.
29481 @deftp {Data Type} agate-configuration
29482 Data type representing the configuration of Agate.
29485 @item @code{package} (default: @code{agate})
29486 The package object of the Agate server.
29488 @item @code{content} (default: @file{"/srv/gemini"})
29489 The directory from which Agate will serve files.
29491 @item @code{cert} (default: @code{#f})
29492 The path to the TLS certificate PEM file to be used for encrypted
29493 connections. Must be filled in with a value from the user.
29495 @item @code{key} (default: @code{#f})
29496 The path to the PKCS8 private key file to be used for encrypted
29497 connections. Must be filled in with a value from the user.
29499 @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
29500 A list of the addresses to listen on.
29502 @item @code{hostname} (default: @code{#f})
29503 The domain name of this Gemini server. Optional.
29505 @item @code{lang} (default: @code{#f})
29506 RFC 4646 language code(s) for text/gemini documents. Optional.
29508 @item @code{silent?} (default: @code{#f})
29509 Set to @code{#t} to disable logging output.
29511 @item @code{serve-secret?} (default: @code{#f})
29512 Set to @code{#t} to serve secret files (files/directories starting with
29515 @item @code{log-ip?} (default: @code{#t})
29516 Whether or not to output IP addresses when logging.
29518 @item @code{user} (default: @code{"agate"})
29519 Owner of the @code{agate} process.
29521 @item @code{group} (default: @code{"agate"})
29522 Owner's group of the @code{agate} process.
29524 @item @code{log-file} (default: @file{"/var/log/agate.log"})
29525 The file which should store the logging output of Agate.
29530 @node Certificate Services
29531 @subsection Certificate Services
29534 @cindex HTTP, HTTPS
29535 @cindex Let's Encrypt
29536 @cindex TLS certificates
29537 The @code{(gnu services certbot)} module provides a service to
29538 automatically obtain a valid TLS certificate from the Let's Encrypt
29539 certificate authority. These certificates can then be used to serve
29540 content securely over HTTPS or other TLS-based protocols, with the
29541 knowledge that the client will be able to verify the server's
29544 @url{https://letsencrypt.org/, Let's Encrypt} provides the
29545 @code{certbot} tool to automate the certification process. This tool
29546 first securely generates a key on the server. It then makes a request
29547 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
29548 checks that the request originates from the host in question by using a
29549 challenge-response protocol, requiring the server to provide its
29550 response over HTTP@. If that protocol completes successfully, the CA
29551 signs the key, resulting in a certificate. That certificate is valid
29552 for a limited period of time, and therefore to continue to provide TLS
29553 services, the server needs to periodically ask the CA to renew its
29556 The certbot service automates this process: the initial key
29557 generation, the initial certification request to the Let's Encrypt
29558 service, the web server challenge/response integration, writing the
29559 certificate to disk, the automated periodic renewals, and the deployment
29560 tasks associated with the renewal (e.g.@: reloading services, copying keys
29561 with different permissions).
29563 Certbot is run twice a day, at a random minute within the hour. It
29564 won't do anything until your certificates are due for renewal or
29565 revoked, but running it regularly would give your service a chance of
29566 staying online in case a Let's Encrypt-initiated revocation happened for
29569 By using this service, you agree to the ACME Subscriber Agreement, which
29570 can be found there:
29571 @url{https://acme-v01.api.letsencrypt.org/directory}.
29573 @defvr {Scheme Variable} certbot-service-type
29574 A service type for the @code{certbot} Let's Encrypt client. Its value
29575 must be a @code{certbot-configuration} record as in this example:
29578 (define %nginx-deploy-hook
29580 "nginx-deploy-hook"
29581 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
29582 (kill pid SIGHUP))))
29584 (service certbot-service-type
29585 (certbot-configuration
29586 (email "foo@@example.net")
29589 (certificate-configuration
29590 (domains '("example.net" "www.example.net"))
29591 (deploy-hook %nginx-deploy-hook))
29592 (certificate-configuration
29593 (domains '("bar.example.net")))))))
29596 See below for details about @code{certbot-configuration}.
29599 @deftp {Data Type} certbot-configuration
29600 Data type representing the configuration of the @code{certbot} service.
29601 This type has the following parameters:
29604 @item @code{package} (default: @code{certbot})
29605 The certbot package to use.
29607 @item @code{webroot} (default: @code{/var/www})
29608 The directory from which to serve the Let's Encrypt challenge/response
29611 @item @code{certificates} (default: @code{()})
29612 A list of @code{certificates-configuration}s for which to generate
29613 certificates and request signatures. Each certificate has a @code{name}
29614 and several @code{domains}.
29616 @item @code{email} (default: @code{#f})
29617 Optional email address used for registration and recovery contact.
29618 Setting this is encouraged as it allows you to receive important
29619 notifications about the account and issued certificates.
29621 @item @code{server} (default: @code{#f})
29622 Optional URL of ACME server. Setting this overrides certbot's default,
29623 which is the Let's Encrypt server.
29625 @item @code{rsa-key-size} (default: @code{2048})
29626 Size of the RSA key.
29628 @item @code{default-location} (default: @i{see below})
29629 The default @code{nginx-location-configuration}. Because @code{certbot}
29630 needs to be able to serve challenges and responses, it needs to be able
29631 to run a web server. It does so by extending the @code{nginx} web
29632 service with an @code{nginx-server-configuration} listening on the
29633 @var{domains} on port 80, and which has a
29634 @code{nginx-location-configuration} for the @code{/.well-known/} URI
29635 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
29636 these nginx configuration data types.
29638 Requests to other URL paths will be matched by the
29639 @code{default-location}, which if present is added to all
29640 @code{nginx-server-configuration}s.
29642 By default, the @code{default-location} will issue a redirect from
29643 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
29644 you to define what to serve on your site via @code{https}.
29646 Pass @code{#f} to not issue a default location.
29650 @deftp {Data Type} certificate-configuration
29651 Data type representing the configuration of a certificate.
29652 This type has the following parameters:
29655 @item @code{name} (default: @i{see below})
29656 This name is used by Certbot for housekeeping and in file paths; it
29657 doesn't affect the content of the certificate itself. To see
29658 certificate names, run @code{certbot certificates}.
29660 Its default is the first provided domain.
29662 @item @code{domains} (default: @code{()})
29663 The first domain provided will be the subject CN of the certificate, and
29664 all domains will be Subject Alternative Names on the certificate.
29666 @item @code{challenge} (default: @code{#f})
29667 The challenge type that has to be run by certbot. If @code{#f} is specified,
29668 default to the HTTP challenge. If a value is specified, defaults to the
29669 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
29670 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
29671 and gives Let's Encrypt permission to log the public IP address of the
29672 requesting machine.
29674 @item @code{csr} (default: @code{#f})
29675 File name of Certificate Signing Request (CSR) in DER or PEM format.
29676 If @code{#f} is specified, this argument will not be passed to certbot.
29677 If a value is specified, certbot will use it to obtain a certificate, instead of
29678 using a self-generated CSR.
29679 The domain-name(s) mentioned in @code{domains}, must be consistent with the
29680 domain-name(s) mentioned in CSR file.
29682 @item @code{authentication-hook} (default: @code{#f})
29683 Command to be run in a shell once for each certificate challenge to be
29684 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
29685 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
29686 contains the validation string and @code{$CERTBOT_TOKEN} contains the
29687 file name of the resource requested when performing an HTTP-01 challenge.
29689 @item @code{cleanup-hook} (default: @code{#f})
29690 Command to be run in a shell once for each certificate challenge that
29691 have been answered by the @code{auth-hook}. For this command, the shell
29692 variables available in the @code{auth-hook} script are still available, and
29693 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
29694 of the @code{auth-hook} script.
29696 @item @code{deploy-hook} (default: @code{#f})
29697 Command to be run in a shell once for each successfully issued
29698 certificate. For this command, the shell variable
29699 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
29700 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
29701 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
29702 contain a space-delimited list of renewed certificate domains (for
29703 example, @samp{"example.com www.example.com"}.
29708 For each @code{certificate-configuration}, the certificate is saved to
29709 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
29710 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
29712 @subsection DNS Services
29713 @cindex DNS (domain name system)
29714 @cindex domain name system (DNS)
29716 The @code{(gnu services dns)} module provides services related to the
29717 @dfn{domain name system} (DNS). It provides a server service for hosting
29718 an @emph{authoritative} DNS server for multiple zones, slave or master.
29719 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
29720 caching and forwarding DNS server for the LAN, which uses
29721 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
29723 @subsubheading Knot Service
29725 An example configuration of an authoritative server for two zones, one master
29729 (define-zone-entries example.org.zone
29730 ;; Name TTL Class Type Data
29731 ("@@" "" "IN" "A" "127.0.0.1")
29732 ("@@" "" "IN" "NS" "ns")
29733 ("ns" "" "IN" "A" "127.0.0.1"))
29735 (define master-zone
29736 (knot-zone-configuration
29737 (domain "example.org")
29739 (origin "example.org")
29740 (entries example.org.zone)))))
29743 (knot-zone-configuration
29744 (domain "plop.org")
29745 (dnssec-policy "default")
29746 (master (list "plop-master"))))
29748 (define plop-master
29749 (knot-remote-configuration
29751 (address (list "208.76.58.171"))))
29755 (services (cons* (service knot-service-type
29756 (knot-configuration
29757 (remotes (list plop-master))
29758 (zones (list master-zone slave-zone))))
29763 @deffn {Scheme Variable} knot-service-type
29764 This is the type for the Knot DNS server.
29766 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
29767 zones, that is to say domain names you would buy from a registrar. This server
29768 is not a resolver, meaning that it can only resolve names for which it is
29769 authoritative. This server can be configured to serve zones as a master server
29770 or a slave server as a per-zone basis. Slave zones will get their data from
29771 masters, and will serve it as an authoritative server. From the point of view
29772 of a resolver, there is no difference between master and slave.
29774 The following data types are used to configure the Knot DNS server:
29777 @deftp {Data Type} knot-key-configuration
29778 Data type representing a key.
29779 This type has the following parameters:
29782 @item @code{id} (default: @code{""})
29783 An identifier for other configuration fields to refer to this key. IDs must
29784 be unique and must not be empty.
29786 @item @code{algorithm} (default: @code{#f})
29787 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
29788 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
29789 and @code{'hmac-sha512}.
29791 @item @code{secret} (default: @code{""})
29792 The secret key itself.
29797 @deftp {Data Type} knot-acl-configuration
29798 Data type representing an Access Control List (ACL) configuration.
29799 This type has the following parameters:
29802 @item @code{id} (default: @code{""})
29803 An identifier for other configuration fields to refer to this key. IDs must be
29804 unique and must not be empty.
29806 @item @code{address} (default: @code{'()})
29807 An ordered list of IP addresses, network subnets, or network ranges represented
29808 with strings. The query must match one of them. Empty value means that
29809 address match is not required.
29811 @item @code{key} (default: @code{'()})
29812 An ordered list of references to keys represented with strings. The string
29813 must match a key ID defined in a @code{knot-key-configuration}. No key means
29814 that a key is not require to match that ACL.
29816 @item @code{action} (default: @code{'()})
29817 An ordered list of actions that are permitted or forbidden by this ACL@. Possible
29818 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
29819 and @code{'update}.
29821 @item @code{deny?} (default: @code{#f})
29822 When true, the ACL defines restrictions. Listed actions are forbidden. When
29823 false, listed actions are allowed.
29828 @deftp {Data Type} zone-entry
29829 Data type representing a record entry in a zone file.
29830 This type has the following parameters:
29833 @item @code{name} (default: @code{"@@"})
29834 The name of the record. @code{"@@"} refers to the origin of the zone. Names
29835 are relative to the origin of the zone. For example, in the @code{example.org}
29836 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
29837 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
29838 refers to @code{ns.example.org}.
29840 @item @code{ttl} (default: @code{""})
29841 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
29843 @item @code{class} (default: @code{"IN"})
29844 The class of the record. Knot currently supports only @code{"IN"} and
29845 partially @code{"CH"}.
29847 @item @code{type} (default: @code{"A"})
29848 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
29849 address), NS (Name Server) and MX (Mail eXchange). Many other types are
29852 @item @code{data} (default: @code{""})
29853 The data contained in the record. For instance an IP address associated with
29854 an A record, or a domain name associated with an NS record. Remember that
29855 domain names are relative to the origin unless they end with a dot.
29860 @deftp {Data Type} zone-file
29861 Data type representing the content of a zone file.
29862 This type has the following parameters:
29865 @item @code{entries} (default: @code{'()})
29866 The list of entries. The SOA record is taken care of, so you don't need to
29867 put it in the list of entries. This list should probably contain an entry
29868 for your primary authoritative DNS server. Other than using a list of entries
29869 directly, you can use @code{define-zone-entries} to define a object containing
29870 the list of entries more easily, that you can later pass to the @code{entries}
29871 field of the @code{zone-file}.
29873 @item @code{origin} (default: @code{""})
29874 The name of your zone. This parameter cannot be empty.
29876 @item @code{ns} (default: @code{"ns"})
29877 The domain of your primary authoritative DNS server. The name is relative to
29878 the origin, unless it ends with a dot. It is mandatory that this primary
29879 DNS server corresponds to an NS record in the zone and that it is associated
29880 to an IP address in the list of entries.
29882 @item @code{mail} (default: @code{"hostmaster"})
29883 An email address people can contact you at, as the owner of the zone. This
29884 is translated as @code{<mail>@@<origin>}.
29886 @item @code{serial} (default: @code{1})
29887 The serial number of the zone. As this is used to keep track of changes by
29888 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
29889 Always increment it when you make a change in your zone.
29891 @item @code{refresh} (default: @code{(* 2 24 3600)})
29892 The frequency at which slaves will do a zone transfer. This value is a number
29893 of seconds. It can be computed by multiplications or with
29894 @code{(string->duration)}.
29896 @item @code{retry} (default: @code{(* 15 60)})
29897 The period after which a slave will retry to contact its master when it fails
29898 to do so a first time.
29900 @item @code{expiry} (default: @code{(* 14 24 3600)})
29901 Default TTL of records. Existing records are considered correct for at most
29902 this amount of time. After this period, resolvers will invalidate their cache
29903 and check again that it still exists.
29905 @item @code{nx} (default: @code{3600})
29906 Default TTL of inexistent records. This delay is usually short because you want
29907 your new domains to reach everyone quickly.
29912 @deftp {Data Type} knot-remote-configuration
29913 Data type representing a remote configuration.
29914 This type has the following parameters:
29917 @item @code{id} (default: @code{""})
29918 An identifier for other configuration fields to refer to this remote. IDs must
29919 be unique and must not be empty.
29921 @item @code{address} (default: @code{'()})
29922 An ordered list of destination IP addresses. Addresses are tried in sequence.
29923 An optional port can be given with the @@ separator. For instance:
29924 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
29926 @item @code{via} (default: @code{'()})
29927 An ordered list of source IP addresses. An empty list will have Knot choose
29928 an appropriate source IP@. An optional port can be given with the @@ separator.
29929 The default is to choose at random.
29931 @item @code{key} (default: @code{#f})
29932 A reference to a key, that is a string containing the identifier of a key
29933 defined in a @code{knot-key-configuration} field.
29938 @deftp {Data Type} knot-keystore-configuration
29939 Data type representing a keystore to hold dnssec keys.
29940 This type has the following parameters:
29943 @item @code{id} (default: @code{""})
29944 The id of the keystore. It must not be empty.
29946 @item @code{backend} (default: @code{'pem})
29947 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
29949 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
29950 The configuration string of the backend. An example for the PKCS#11 is:
29951 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
29952 For the pem backend, the string represents a path in the file system.
29957 @deftp {Data Type} knot-policy-configuration
29958 Data type representing a dnssec policy. Knot DNS is able to automatically
29959 sign your zones. It can either generate and manage your keys automatically or
29960 use keys that you generate.
29962 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
29963 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
29964 zone. In order to be trusted, the KSK needs to be present in the parent zone
29965 (usually a top-level domain). If your registrar supports dnssec, you will
29966 have to send them your KSK's hash so they can add a DS record in their zone.
29967 This is not automated and need to be done each time you change your KSK.
29969 The policy also defines the lifetime of keys. Usually, ZSK can be changed
29970 easily and use weaker cryptographic functions (they use lower parameters) in
29971 order to sign records quickly, so they are changed often. The KSK however
29972 requires manual interaction with the registrar, so they are changed less often
29973 and use stronger parameters because they sign only one record.
29975 This type has the following parameters:
29978 @item @code{id} (default: @code{""})
29979 The id of the policy. It must not be empty.
29981 @item @code{keystore} (default: @code{"default"})
29982 A reference to a keystore, that is a string containing the identifier of a
29983 keystore defined in a @code{knot-keystore-configuration} field. The
29984 @code{"default"} identifier means the default keystore (a kasp database that
29985 was setup by this service).
29987 @item @code{manual?} (default: @code{#f})
29988 Whether the key management is manual or automatic.
29990 @item @code{single-type-signing?} (default: @code{#f})
29991 When @code{#t}, use the Single-Type Signing Scheme.
29993 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
29994 An algorithm of signing keys and issued signatures.
29996 @item @code{ksk-size} (default: @code{256})
29997 The length of the KSK@. Note that this value is correct for the default
29998 algorithm, but would be unsecure for other algorithms.
30000 @item @code{zsk-size} (default: @code{256})
30001 The length of the ZSK@. Note that this value is correct for the default
30002 algorithm, but would be unsecure for other algorithms.
30004 @item @code{dnskey-ttl} (default: @code{'default})
30005 The TTL value for DNSKEY records added into zone apex. The special
30006 @code{'default} value means same as the zone SOA TTL.
30008 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
30009 The period between ZSK publication and the next rollover initiation.
30011 @item @code{propagation-delay} (default: @code{(* 24 3600)})
30012 An extra delay added for each key rollover step. This value should be high
30013 enough to cover propagation of data from the master server to all slaves.
30015 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
30016 A validity period of newly issued signatures.
30018 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
30019 A period how long before a signature expiration the signature will be refreshed.
30021 @item @code{nsec3?} (default: @code{#f})
30022 When @code{#t}, NSEC3 will be used instead of NSEC.
30024 @item @code{nsec3-iterations} (default: @code{5})
30025 The number of additional times the hashing is performed.
30027 @item @code{nsec3-salt-length} (default: @code{8})
30028 The length of a salt field in octets, which is appended to the original owner
30029 name before hashing.
30031 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
30032 The validity period of newly issued salt field.
30037 @deftp {Data Type} knot-zone-configuration
30038 Data type representing a zone served by Knot.
30039 This type has the following parameters:
30042 @item @code{domain} (default: @code{""})
30043 The domain served by this configuration. It must not be empty.
30045 @item @code{file} (default: @code{""})
30046 The file where this zone is saved. This parameter is ignored by master zones.
30047 Empty means default location that depends on the domain name.
30049 @item @code{zone} (default: @code{(zone-file)})
30050 The content of the zone file. This parameter is ignored by slave zones. It
30051 must contain a zone-file record.
30053 @item @code{master} (default: @code{'()})
30054 A list of master remotes. When empty, this zone is a master. When set, this
30055 zone is a slave. This is a list of remotes identifiers.
30057 @item @code{ddns-master} (default: @code{#f})
30058 The main master. When empty, it defaults to the first master in the list of
30061 @item @code{notify} (default: @code{'()})
30062 A list of slave remote identifiers.
30064 @item @code{acl} (default: @code{'()})
30065 A list of acl identifiers.
30067 @item @code{semantic-checks?} (default: @code{#f})
30068 When set, this adds more semantic checks to the zone.
30070 @item @code{zonefile-sync} (default: @code{0})
30071 The delay between a modification in memory and on disk. 0 means immediate
30074 @item @code{zonefile-load} (default: @code{#f})
30075 The way the zone file contents are applied during zone load. Possible values
30079 @item @code{#f} for using the default value from Knot,
30080 @item @code{'none} for not using the zone file at all,
30081 @item @code{'difference} for computing the difference between already available
30082 contents and zone contents and applying it to the current zone contents,
30083 @item @code{'difference-no-serial} for the same as @code{'difference}, but
30084 ignoring the SOA serial in the zone file, while the server takes care of it
30086 @item @code{'whole} for loading zone contents from the zone file.
30089 @item @code{journal-content} (default: @code{#f})
30090 The way the journal is used to store zone and its changes. Possible values
30091 are @code{'none} to not use it at all, @code{'changes} to store changes and
30092 @code{'all} to store contents. @code{#f} does not set this option, so the
30093 default value from Knot is used.
30095 @item @code{max-journal-usage} (default: @code{#f})
30096 The maximum size for the journal on disk. @code{#f} does not set this option,
30097 so the default value from Knot is used.
30099 @item @code{max-journal-depth} (default: @code{#f})
30100 The maximum size of the history. @code{#f} does not set this option, so the
30101 default value from Knot is used.
30103 @item @code{max-zone-size} (default: @code{#f})
30104 The maximum size of the zone file. This limit is enforced for incoming
30105 transfer and updates. @code{#f} does not set this option, so the default
30106 value from Knot is used.
30108 @item @code{dnssec-policy} (default: @code{#f})
30109 A reference to a @code{knot-policy-configuration} record, or the special
30110 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
30113 @item @code{serial-policy} (default: @code{'increment})
30114 A policy between @code{'increment} and @code{'unixtime}.
30119 @deftp {Data Type} knot-configuration
30120 Data type representing the Knot configuration.
30121 This type has the following parameters:
30124 @item @code{knot} (default: @code{knot})
30127 @item @code{run-directory} (default: @code{"/var/run/knot"})
30128 The run directory. This directory will be used for pid file and sockets.
30130 @item @code{includes} (default: @code{'()})
30131 A list of strings or file-like objects denoting other files that must be
30132 included at the top of the configuration file.
30134 @cindex secrets, Knot service
30135 This can be used to manage secrets out-of-band. For example, secret
30136 keys may be stored in an out-of-band file not managed by Guix, and
30137 thus not visible in @file{/gnu/store}---e.g., you could store secret
30138 key configuration in @file{/etc/knot/secrets.conf} and add this file
30139 to the @code{includes} list.
30141 One can generate a secret tsig key (for nsupdate and zone transfers with the
30142 keymgr command from the knot package. Note that the package is not automatically
30143 installed by the service. The following example shows how to generate a new
30147 keymgr -t mysecret > /etc/knot/secrets.conf
30148 chmod 600 /etc/knot/secrets.conf
30151 Also note that the generated key will be named @var{mysecret}, so it is the
30152 name that needs to be used in the @var{key} field of the
30153 @code{knot-acl-configuration} record and in other places that need to refer
30156 It can also be used to add configuration not supported by this interface.
30158 @item @code{listen-v4} (default: @code{"0.0.0.0"})
30159 An ip address on which to listen.
30161 @item @code{listen-v6} (default: @code{"::"})
30162 An ip address on which to listen.
30164 @item @code{listen-port} (default: @code{53})
30165 A port on which to listen.
30167 @item @code{keys} (default: @code{'()})
30168 The list of knot-key-configuration used by this configuration.
30170 @item @code{acls} (default: @code{'()})
30171 The list of knot-acl-configuration used by this configuration.
30173 @item @code{remotes} (default: @code{'()})
30174 The list of knot-remote-configuration used by this configuration.
30176 @item @code{zones} (default: @code{'()})
30177 The list of knot-zone-configuration used by this configuration.
30182 @subsubheading Knot Resolver Service
30184 @deffn {Scheme Variable} knot-resolver-service-type
30185 This is the type of the knot resolver service, whose value should be
30186 an @code{knot-resolver-configuration} object as in this example:
30189 (service knot-resolver-service-type
30190 (knot-resolver-configuration
30191 (kresd-config-file (plain-file "kresd.conf" "
30192 net.listen('192.168.0.1', 5353)
30193 user('knot-resolver', 'knot-resolver')
30194 modules = @{ 'hints > iterate', 'stats', 'predict' @}
30195 cache.size = 100 * MB
30199 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
30202 @deftp {Data Type} knot-resolver-configuration
30203 Data type representing the configuration of knot-resolver.
30206 @item @code{package} (default: @var{knot-resolver})
30207 Package object of the knot DNS resolver.
30209 @item @code{kresd-config-file} (default: %kresd.conf)
30210 File-like object of the kresd configuration file to use, by default it
30211 will listen on @code{127.0.0.1} and @code{::1}.
30213 @item @code{garbage-collection-interval} (default: 1000)
30214 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
30220 @subsubheading Dnsmasq Service
30222 @deffn {Scheme Variable} dnsmasq-service-type
30223 This is the type of the dnsmasq service, whose value should be an
30224 @code{dnsmasq-configuration} object as in this example:
30227 (service dnsmasq-service-type
30228 (dnsmasq-configuration
30230 (servers '("192.168.1.1"))))
30234 @deftp {Data Type} dnsmasq-configuration
30235 Data type representing the configuration of dnsmasq.
30238 @item @code{package} (default: @var{dnsmasq})
30239 Package object of the dnsmasq server.
30241 @item @code{no-hosts?} (default: @code{#f})
30242 When true, don't read the hostnames in /etc/hosts.
30244 @item @code{port} (default: @code{53})
30245 The port to listen on. Setting this to zero completely disables DNS
30246 responses, leaving only DHCP and/or TFTP functions.
30248 @item @code{local-service?} (default: @code{#t})
30249 Accept DNS queries only from hosts whose address is on a local subnet,
30250 ie a subnet for which an interface exists on the server.
30252 @item @code{listen-addresses} (default: @code{'()})
30253 Listen on the given IP addresses.
30255 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
30256 The file to read the IP address of the upstream nameservers from.
30258 @item @code{no-resolv?} (default: @code{#f})
30259 When true, don't read @var{resolv-file}.
30261 @item @code{forward-private-reverse-lookup?} (default: @code{#t})
30262 When false, all reverse lookups for private IP ranges are answered with
30263 "no such domain" rather than being forwarded upstream.
30265 @item @code{query-servers-in-order?} (default: @code{#f})
30266 When true, dnsmasq queries the servers in the same order as they appear
30269 @item @code{servers} (default: @code{'()})
30270 Specify IP address of upstream servers directly.
30272 @item @code{addresses} (default: @code{'()})
30273 For each entry, specify an IP address to return for any host in the
30274 given domains. Queries in the domains are never forwarded and always
30275 replied to with the specified IP address.
30277 This is useful for redirecting hosts locally, for example:
30280 (service dnsmasq-service-type
30281 (dnsmasq-configuration
30283 '(; Redirect to a local web-server.
30284 "/example.org/127.0.0.1"
30285 ; Redirect subdomain to a specific IP.
30286 "/subdomain.example.org/192.168.1.42"))))
30289 Note that rules in @file{/etc/hosts} take precedence over this.
30291 @item @code{cache-size} (default: @code{150})
30292 Set the size of dnsmasq's cache. Setting the cache size to zero
30295 @item @code{negative-cache?} (default: @code{#t})
30296 When false, disable negative caching.
30298 @item @code{cpe-id} (default: @code{#f})
30299 If set, add a CPE (Customer-Premises Equipment) identifier to DNS
30300 queries which are forwarded upstream.
30302 @item @code{tftp-enable?} (default: @code{#f})
30303 Whether to enable the built-in TFTP server.
30305 @item @code{tftp-no-fail?} (default: @code{#f})
30306 If true, does not fail dnsmasq if the TFTP server could not start up.
30308 @item @code{tftp-single-port?} (default: @code{#f})
30309 Whether to use only one single port for TFTP.
30311 @item @code{tftp-secure?} (default: @code{#f})
30312 If true, only files owned by the user running the dnsmasq process are accessible.
30314 If dnsmasq is being run as root, different rules apply:
30315 @code{tftp-secure?} has no effect, but only files which have the
30316 world-readable bit set are accessible.
30318 @item @code{tftp-max} (default: @code{#f})
30319 If set, sets the maximal number of concurrent connections allowed.
30321 @item @code{tftp-mtu} (default: @code{#f})
30322 If set, sets the MTU for TFTP packets to that value.
30324 @item @code{tftp-no-blocksize?} (default: @code{#f})
30325 If true, stops the TFTP server from negotiating the blocksize with a client.
30327 @item @code{tftp-lowercase?} (default: @code{#f})
30328 Whether to convert all filenames in TFTP requests to lowercase.
30330 @item @code{tftp-port-range} (default: @code{#f})
30331 If set, fixes the dynamical ports (one per client) to the given range
30332 (@code{"<start>,<end>"}).
30334 @item @code{tftp-root} (default: @code{/var/empty,lo})
30335 Look for files to transfer using TFTP relative to the given directory.
30336 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
30337 getting outside the specified root. Absolute paths (starting with @samp{/}) are
30338 allowed, but they must be within the TFTP-root. If the optional interface
30339 argument is given, the directory is only used for TFTP requests via that
30342 @item @code{tftp-unique-root} (default: @code{#f})
30343 If set, add the IP or hardware address of the TFTP client as a path component
30344 on the end of the TFTP-root. Only valid if a TFTP root is set and the
30345 directory exists. Defaults to adding IP address (in standard dotted-quad
30348 For instance, if @option{--tftp-root} is @samp{/tftp} and client
30349 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
30350 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
30351 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
30352 append the MAC address instead, using lowercase zero padded digits
30353 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
30354 resolving MAC addresses is only possible if the client is in the local
30355 network or obtained a DHCP lease from dnsmasq.
30360 @subsubheading ddclient Service
30363 The ddclient service described below runs the ddclient daemon, which takes
30364 care of automatically updating DNS entries for service providers such as
30365 @uref{https://dyn.com/dns/, Dyn}.
30367 The following example show instantiates the service with its default
30371 (service ddclient-service-type)
30374 Note that ddclient needs to access credentials that are stored in a
30375 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
30376 @code{secret-file} below). You are expected to create this file manually, in
30377 an ``out-of-band'' fashion (you @emph{could} make this file part of the
30378 service configuration, for instance by using @code{plain-file}, but it will be
30379 world-readable @i{via} @file{/gnu/store}). See the examples in the
30380 @file{share/ddclient} directory of the @code{ddclient} package.
30382 @c %start of fragment
30384 Available @code{ddclient-configuration} fields are:
30386 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
30387 The ddclient package.
30391 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
30392 The period after which ddclient will retry to check IP and domain name.
30394 Defaults to @samp{300}.
30398 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
30399 Use syslog for the output.
30401 Defaults to @samp{#t}.
30405 @deftypevr {@code{ddclient-configuration} parameter} string mail
30408 Defaults to @samp{"root"}.
30412 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
30413 Mail failed update to user.
30415 Defaults to @samp{"root"}.
30419 @deftypevr {@code{ddclient-configuration} parameter} string pid
30420 The ddclient PID file.
30422 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
30426 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
30427 Enable SSL support.
30429 Defaults to @samp{#t}.
30433 @deftypevr {@code{ddclient-configuration} parameter} string user
30434 Specifies the user name or ID that is used when running ddclient
30437 Defaults to @samp{"ddclient"}.
30441 @deftypevr {@code{ddclient-configuration} parameter} string group
30442 Group of the user who will run the ddclient program.
30444 Defaults to @samp{"ddclient"}.
30448 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
30449 Secret file which will be appended to @file{ddclient.conf} file. This
30450 file contains credentials for use by ddclient. You are expected to
30451 create it manually.
30453 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
30457 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
30458 Extra options will be appended to @file{ddclient.conf} file.
30460 Defaults to @samp{()}.
30465 @c %end of fragment
30469 @subsection VPN Services
30470 @cindex VPN (virtual private network)
30471 @cindex virtual private network (VPN)
30473 The @code{(gnu services vpn)} module provides services related to
30474 @dfn{virtual private networks} (VPNs).
30476 @subsubheading Bitmask
30478 @defvr {Scheme Variable} bitmask-service-type
30479 A service type for the @uref{https://bitmask.net, Bitmask} VPN client. It makes
30480 the client available in the system and loads its polkit policy. Please note that
30481 the client expects an active polkit-agent, which is either run by your
30482 desktop-environment or should be run manually.
30485 @subsubheading OpenVPN
30487 It provides a @emph{client} service for your machine to connect to a
30488 VPN, and a @emph{server} service for your machine to host a VPN@.
30490 @deffn {Scheme Procedure} openvpn-client-service @
30491 [#:config (openvpn-client-configuration)]
30493 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
30496 @deffn {Scheme Procedure} openvpn-server-service @
30497 [#:config (openvpn-server-configuration)]
30499 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
30501 Both can be run simultaneously.
30504 @c %automatically generated documentation
30506 @deftp {Data Type} openvpn-client-configuration
30507 Available @code{openvpn-client-configuration} fields are:
30510 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30511 The OpenVPN package.
30513 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30514 The OpenVPN pid file.
30516 @item @code{proto} (default: @code{udp}) (type: proto)
30517 The protocol (UDP or TCP) used to open a channel between clients and
30520 @item @code{dev} (default: @code{tun}) (type: dev)
30521 The device type used to represent the VPN connection.
30523 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30524 The certificate authority to check connections against.
30526 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30527 The certificate of the machine the daemon is running on. It should be
30528 signed by the authority given in @code{ca}.
30530 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30531 The key of the machine the daemon is running on. It must be the key
30532 whose certificate is @code{cert}.
30534 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30535 Whether to use the lzo compression algorithm.
30537 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30538 Don't re-read key files across SIGUSR1 or --ping-restart.
30540 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30541 Don't close and reopen TUN/TAP device or run up/down scripts across
30542 SIGUSR1 or --ping-restart restarts.
30544 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30545 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30546 poll/epoll/select prior to the write operation.
30548 @item @code{verbosity} (default: @code{3}) (type: number)
30551 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-client)
30552 Add an additional layer of HMAC authentication on top of the TLS control
30553 channel to protect against DoS attacks.
30555 @item @code{auth-user-pass} (type: maybe-string)
30556 Authenticate with server using username/password. The option is a file
30557 containing username/password on 2 lines. Do not use a file-like object
30558 as it would be added to the store and readable by any user.
30560 @item @code{verify-key-usage?} (default: @code{#t}) (type: key-usage)
30561 Whether to check the server certificate has server usage extension.
30563 @item @code{bind?} (default: @code{#f}) (type: bind)
30564 Bind to a specific local port number.
30566 @item @code{resolv-retry?} (default: @code{#t}) (type: resolv-retry)
30567 Retry resolving server address.
30569 @item @code{remote} (default: @code{()}) (type: openvpn-remote-list)
30570 A list of remote servers to connect to.
30572 @deftp {Data Type} openvpn-remote-configuration
30573 Available @code{openvpn-remote-configuration} fields are:
30576 @item @code{name} (default: @code{"my-server"}) (type: string)
30579 @item @code{port} (default: @code{1194}) (type: number)
30580 Port number the server listens to.
30590 @c %end of automatic openvpn-client documentation
30592 @c %automatically generated documentation
30594 @deftp {Data Type} openvpn-server-configuration
30595 Available @code{openvpn-server-configuration} fields are:
30598 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30599 The OpenVPN package.
30601 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30602 The OpenVPN pid file.
30604 @item @code{proto} (default: @code{udp}) (type: proto)
30605 The protocol (UDP or TCP) used to open a channel between clients and
30608 @item @code{dev} (default: @code{tun}) (type: dev)
30609 The device type used to represent the VPN connection.
30611 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30612 The certificate authority to check connections against.
30614 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30615 The certificate of the machine the daemon is running on. It should be
30616 signed by the authority given in @code{ca}.
30618 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30619 The key of the machine the daemon is running on. It must be the key
30620 whose certificate is @code{cert}.
30622 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30623 Whether to use the lzo compression algorithm.
30625 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30626 Don't re-read key files across SIGUSR1 or --ping-restart.
30628 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30629 Don't close and reopen TUN/TAP device or run up/down scripts across
30630 SIGUSR1 or --ping-restart restarts.
30632 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30633 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30634 poll/epoll/select prior to the write operation.
30636 @item @code{verbosity} (default: @code{3}) (type: number)
30639 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-server)
30640 Add an additional layer of HMAC authentication on top of the TLS control
30641 channel to protect against DoS attacks.
30643 @item @code{port} (default: @code{1194}) (type: number)
30644 Specifies the port number on which the server listens.
30646 @item @code{server} (default: @code{"10.8.0.0 255.255.255.0"}) (type: ip-mask)
30647 An ip and mask specifying the subnet inside the virtual network.
30649 @item @code{server-ipv6} (default: @code{#f}) (type: cidr6)
30650 A CIDR notation specifying the IPv6 subnet inside the virtual network.
30652 @item @code{dh} (default: @code{"/etc/openvpn/dh2048.pem"}) (type: string)
30653 The Diffie-Hellman parameters file.
30655 @item @code{ifconfig-pool-persist} (default: @code{"/etc/openvpn/ipp.txt"}) (type: string)
30656 The file that records client IPs.
30658 @item @code{redirect-gateway?} (default: @code{#f}) (type: gateway)
30659 When true, the server will act as a gateway for its clients.
30661 @item @code{client-to-client?} (default: @code{#f}) (type: boolean)
30662 When true, clients are allowed to talk to each other inside the VPN.
30664 @item @code{keepalive} (default: @code{(10 120)}) (type: keepalive)
30665 Causes ping-like messages to be sent back and forth over the link so
30666 that each side knows when the other side has gone down. @code{keepalive}
30667 requires a pair. The first element is the period of the ping sending,
30668 and the second element is the timeout before considering the other side
30671 @item @code{max-clients} (default: @code{100}) (type: number)
30672 The maximum number of clients.
30674 @item @code{status} (default: @code{"/var/run/openvpn/status"}) (type: string)
30675 The status file. This file shows a small report on current connection.
30676 It is truncated and rewritten every minute.
30678 @item @code{client-config-dir} (default: @code{()}) (type: openvpn-ccd-list)
30679 The list of configuration for some clients.
30685 @c %end of automatic openvpn-server documentation
30687 @subheading strongSwan
30689 Currently, the strongSwan service only provides legacy-style configuration with
30690 @file{ipsec.conf} and @file{ipsec.secrets} files.
30692 @defvr {Scheme Variable} strongswan-service-type
30693 A service type for configuring strongSwan for IPsec @acronym{VPN,
30694 Virtual Private Networking}. Its value must be a
30695 @code{strongswan-configuration} record as in this example:
30698 (service strongswan-service-type
30699 (strongswan-configuration
30700 (ipsec-conf "/etc/ipsec.conf")
30701 (ipsec-secrets "/etc/ipsec.secrets")))
30706 @deftp {Data Type} strongswan-configuration
30707 Data type representing the configuration of the StrongSwan service.
30710 @item @code{strongswan}
30711 The strongSwan package to use for this service.
30713 @item @code{ipsec-conf} (default: @code{#f})
30714 The file name of your @file{ipsec.conf}. If not @code{#f}, then this and
30715 @code{ipsec-secrets} must both be strings.
30717 @item @code{ipsec-secrets} (default @code{#f})
30718 The file name of your @file{ipsec.secrets}. If not @code{#f}, then this and
30719 @code{ipsec-conf} must both be strings.
30724 @subsubheading Wireguard
30726 @defvr {Scheme Variable} wireguard-service-type
30727 A service type for a Wireguard tunnel interface. Its value must be a
30728 @code{wireguard-configuration} record as in this example:
30731 (service wireguard-service-type
30732 (wireguard-configuration
30737 (endpoint "my.wireguard.com:51820")
30738 (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
30739 (allowed-ips '("10.0.0.2/32")))))))
30744 @deftp {Data Type} wireguard-configuration
30745 Data type representing the configuration of the Wireguard service.
30748 @item @code{wireguard}
30749 The wireguard package to use for this service.
30751 @item @code{interface} (default: @code{"wg0"})
30752 The interface name for the VPN.
30754 @item @code{addresses} (default: @code{'("10.0.0.1/32")})
30755 The IP addresses to be assigned to the above interface.
30757 @item @code{port} (default: @code{51820})
30758 The port on which to listen for incoming connections.
30760 @item @code{dns} (default: @code{#f})
30761 The DNS server(s) to announce to VPN clients via DHCP.
30763 @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
30764 The private key file for the interface. It is automatically generated if
30765 the file does not exist.
30767 @item @code{peers} (default: @code{'()})
30768 The authorized peers on this interface. This is a list of
30769 @var{wireguard-peer} records.
30774 @deftp {Data Type} wireguard-peer
30775 Data type representing a Wireguard peer attached to a given interface.
30781 @item @code{endpoint} (default: @code{#f})
30782 The optional endpoint for the peer, such as
30783 @code{"demo.wireguard.com:51820"}.
30785 @item @code{public-key}
30786 The peer public-key represented as a base64 string.
30788 @item @code{allowed-ips}
30789 A list of IP addresses from which incoming traffic for this peer is
30790 allowed and to which incoming traffic for this peer is directed.
30792 @item @code{keep-alive} (default: @code{#f})
30793 An optional time interval in seconds. A packet will be sent to the
30794 server endpoint once per time interval. This helps receiving
30795 incoming connections from this peer when you are behind a NAT or
30801 @node Network File System
30802 @subsection Network File System
30805 The @code{(gnu services nfs)} module provides the following services,
30806 which are most commonly used in relation to mounting or exporting
30807 directory trees as @dfn{network file systems} (NFS).
30809 While it is possible to use the individual components that together make
30810 up a Network File System service, we recommended to configure an NFS
30811 server with the @code{nfs-service-type}.
30813 @subsubheading NFS Service
30814 @cindex NFS, server
30816 The NFS service takes care of setting up all NFS component services,
30817 kernel configuration file systems, and installs configuration files in
30818 the locations that NFS expects.
30820 @defvr {Scheme Variable} nfs-service-type
30821 A service type for a complete NFS server.
30824 @deftp {Data Type} nfs-configuration
30825 This data type represents the configuration of the NFS service and all
30828 It has the following parameters:
30830 @item @code{nfs-utils} (default: @code{nfs-utils})
30831 The nfs-utils package to use.
30833 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
30834 If a list of string values is provided, the @command{rpc.nfsd} daemon
30835 will be limited to supporting the given versions of the NFS protocol.
30837 @item @code{exports} (default: @code{'()})
30838 This is a list of directories the NFS server should export. Each entry
30839 is a list consisting of two elements: a directory name and a string
30840 containing all options. This is an example in which the directory
30841 @file{/export} is served to all NFS clients as a read-only share:
30847 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
30850 @item @code{rpcmountd-port} (default: @code{#f})
30851 The network port that the @command{rpc.mountd} daemon should use.
30853 @item @code{rpcstatd-port} (default: @code{#f})
30854 The network port that the @command{rpc.statd} daemon should use.
30856 @item @code{rpcbind} (default: @code{rpcbind})
30857 The rpcbind package to use.
30859 @item @code{idmap-domain} (default: @code{"localdomain"})
30860 The local NFSv4 domain name.
30862 @item @code{nfsd-port} (default: @code{2049})
30863 The network port that the @command{nfsd} daemon should use.
30865 @item @code{nfsd-threads} (default: @code{8})
30866 The number of threads used by the @command{nfsd} daemon.
30868 @item @code{nfsd-tcp?} (default: @code{#t})
30869 Whether the @command{nfsd} daemon should listen on a TCP socket.
30871 @item @code{nfsd-udp?} (default: @code{#f})
30872 Whether the @command{nfsd} daemon should listen on a UDP socket.
30874 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
30875 The directory where the pipefs file system is mounted.
30877 @item @code{debug} (default: @code{'()"})
30878 A list of subsystems for which debugging output should be enabled. This
30879 is a list of symbols. Any of these symbols are valid: @code{nfsd},
30880 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
30884 If you don't need a complete NFS service or prefer to build it yourself
30885 you can use the individual component services that are documented below.
30887 @subsubheading RPC Bind Service
30890 The RPC Bind service provides a facility to map program numbers into
30891 universal addresses.
30892 Many NFS related services use this facility. Hence it is automatically
30893 started when a dependent service starts.
30895 @defvr {Scheme Variable} rpcbind-service-type
30896 A service type for the RPC portmapper daemon.
30900 @deftp {Data Type} rpcbind-configuration
30901 Data type representing the configuration of the RPC Bind Service.
30902 This type has the following parameters:
30904 @item @code{rpcbind} (default: @code{rpcbind})
30905 The rpcbind package to use.
30907 @item @code{warm-start?} (default: @code{#t})
30908 If this parameter is @code{#t}, then the daemon will read a
30909 state file on startup thus reloading state information saved by a previous
30915 @subsubheading Pipefs Pseudo File System
30919 The pipefs file system is used to transfer NFS related data
30920 between the kernel and user space programs.
30922 @defvr {Scheme Variable} pipefs-service-type
30923 A service type for the pipefs pseudo file system.
30926 @deftp {Data Type} pipefs-configuration
30927 Data type representing the configuration of the pipefs pseudo file system service.
30928 This type has the following parameters:
30930 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
30931 The directory to which the file system is to be attached.
30936 @subsubheading GSS Daemon Service
30939 @cindex global security system
30941 The @dfn{global security system} (GSS) daemon provides strong security for RPC
30943 Before exchanging RPC requests an RPC client must establish a security
30944 context. Typically this is done using the Kerberos command @command{kinit}
30945 or automatically at login time using PAM services (@pxref{Kerberos Services}).
30947 @defvr {Scheme Variable} gss-service-type
30948 A service type for the Global Security System (GSS) daemon.
30951 @deftp {Data Type} gss-configuration
30952 Data type representing the configuration of the GSS daemon service.
30953 This type has the following parameters:
30955 @item @code{nfs-utils} (default: @code{nfs-utils})
30956 The package in which the @command{rpc.gssd} command is to be found.
30958 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
30959 The directory where the pipefs file system is mounted.
30965 @subsubheading IDMAP Daemon Service
30967 @cindex name mapper
30969 The idmap daemon service provides mapping between user IDs and user names.
30970 Typically it is required in order to access file systems mounted via NFSv4.
30972 @defvr {Scheme Variable} idmap-service-type
30973 A service type for the Identity Mapper (IDMAP) daemon.
30976 @deftp {Data Type} idmap-configuration
30977 Data type representing the configuration of the IDMAP daemon service.
30978 This type has the following parameters:
30980 @item @code{nfs-utils} (default: @code{nfs-utils})
30981 The package in which the @command{rpc.idmapd} command is to be found.
30983 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
30984 The directory where the pipefs file system is mounted.
30986 @item @code{domain} (default: @code{#f})
30987 The local NFSv4 domain name.
30988 This must be a string or @code{#f}.
30989 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
30991 @item @code{verbosity} (default: @code{0})
30992 The verbosity level of the daemon.
30997 @node Continuous Integration
30998 @subsection Continuous Integration
31000 @cindex continuous integration
31001 @uref{https://guix.gnu.org/cuirass/, Cuirass} is a continuous
31002 integration tool for Guix. It can be used both for development and for
31003 providing substitutes to others (@pxref{Substitutes}).
31005 The @code{(gnu services cuirass)} module provides the following service.
31007 @defvr {Scheme Procedure} cuirass-service-type
31008 The type of the Cuirass service. Its value must be a
31009 @code{cuirass-configuration} object, as described below.
31012 To add build jobs, you have to set the @code{specifications} field of
31013 the configuration. For instance, the following example will build all
31014 the packages provided by the @code{my-channel} channel.
31017 (define %cuirass-specs
31018 #~(list (specification
31019 (name "my-channel")
31020 (build '(channels my-channel))
31024 (url "https://my-channel.git"))
31025 %default-channels)))))
31027 (service cuirass-service-type
31028 (cuirass-configuration
31029 (specifications %cuirass-specs)))
31032 To build the @code{linux-libre} package defined by the default Guix
31033 channel, one can use the following configuration.
31036 (define %cuirass-specs
31037 #~(list (specification
31039 (build '(packages "linux-libre")))))
31041 (service cuirass-service-type
31042 (cuirass-configuration
31043 (specifications %cuirass-specs)))
31046 The other configuration possibilities, as well as the specification
31047 record itself are described in the Cuirass manual
31048 (@pxref{Specifications,,, cuirass, Cuirass}).
31050 While information related to build jobs is located directly in the
31051 specifications, global settings for the @command{cuirass} process are
31052 accessible in other @code{cuirass-configuration} fields.
31054 @deftp {Data Type} cuirass-configuration
31055 Data type representing the configuration of Cuirass.
31058 @item @code{cuirass} (default: @code{cuirass})
31059 The Cuirass package to use.
31061 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
31062 Location of the log file.
31064 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
31065 Location of the log file used by the web interface.
31067 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
31068 Location of the repository cache.
31070 @item @code{user} (default: @code{"cuirass"})
31071 Owner of the @code{cuirass} process.
31073 @item @code{group} (default: @code{"cuirass"})
31074 Owner's group of the @code{cuirass} process.
31076 @item @code{interval} (default: @code{60})
31077 Number of seconds between the poll of the repositories followed by the
31080 @item @code{parameters} (default: @code{#f})
31081 Read parameters from the given @var{parameters} file. The supported
31082 parameters are described here (@pxref{Parameters,,, cuirass, Cuirass}).
31084 @item @code{remote-server} (default: @code{#f})
31085 A @code{cuirass-remote-server-configuration} record to use the build
31086 remote mechanism or @code{#f} to use the default build mechanism.
31088 @item @code{database} (default: @code{"dbname=cuirass host=/var/run/postgresql"})
31089 Use @var{database} as the database containing the jobs and the past
31090 build results. Since Cuirass uses PostgreSQL as a database engine,
31091 @var{database} must be a string such as @code{"dbname=cuirass
31094 @item @code{port} (default: @code{8081})
31095 Port number used by the HTTP server.
31097 @item @code{host} (default: @code{"localhost"})
31098 Listen on the network interface for @var{host}. The default is to
31099 accept connections from localhost.
31101 @item @code{specifications} (default: @code{#~'()})
31102 A gexp (@pxref{G-Expressions}) that evaluates to a list of
31103 specifications records. The specification record is described in the
31104 Cuirass manual (@pxref{Specifications,,, cuirass, Cuirass}).
31106 @item @code{use-substitutes?} (default: @code{#f})
31107 This allows using substitutes to avoid building every dependencies of a job
31110 @item @code{one-shot?} (default: @code{#f})
31111 Only evaluate specifications and build derivations once.
31113 @item @code{fallback?} (default: @code{#f})
31114 When substituting a pre-built binary fails, fall back to building
31117 @item @code{extra-options} (default: @code{'()})
31118 Extra options to pass when running the Cuirass processes.
31123 @cindex remote build
31124 @subsubheading Cuirass remote building
31126 Cuirass supports two mechanisms to build derivations.
31129 @item Using the local Guix daemon.
31130 This is the default build mechanism. Once the build jobs are
31131 evaluated, they are sent to the local Guix daemon. Cuirass then
31132 listens to the Guix daemon output to detect the various build events.
31134 @item Using the remote build mechanism.
31135 The build jobs are not submitted to the local Guix daemon. Instead, a
31136 remote server dispatches build requests to the connect remote workers,
31137 according to the build priorities.
31141 To enable this build mode a @code{cuirass-remote-server-configuration}
31142 record must be passed as @code{remote-server} argument of the
31143 @code{cuirass-configuration} record. The
31144 @code{cuirass-remote-server-configuration} record is described below.
31146 This build mode scales way better than the default build mode. This is
31147 the build mode that is used on the GNU Guix build farm at
31148 @url{https://ci.guix.gnu.org}. It should be preferred when using
31149 Cuirass to build large amount of packages.
31151 @deftp {Data Type} cuirass-remote-server-configuration
31152 Data type representing the configuration of the Cuirass remote-server.
31155 @item @code{backend-port} (default: @code{5555})
31156 The TCP port for communicating with @code{remote-worker} processes
31157 using ZMQ. It defaults to @code{5555}.
31159 @item @code{log-port} (default: @code{5556})
31160 The TCP port of the log server. It defaults to @code{5556}.
31162 @item @code{publish-port} (default: @code{5557})
31163 The TCP port of the publish server. It defaults to @code{5557}.
31165 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-server.log"})
31166 Location of the log file.
31168 @item @code{cache} (default: @code{"/var/cache/cuirass/remote"})
31169 Use @var{cache} directory to cache build log files.
31171 @item @code{trigger-url} (default: @code{#f})
31172 Once a substitute is successfully fetched, trigger substitute baking at
31175 @item @code{publish?} (default: @code{#t})
31176 If set to false, do not start a publish server and ignore the
31177 @code{publish-port} argument. This can be useful if there is already a
31178 standalone publish server standing next to the remote server.
31180 @item @code{public-key}
31181 @item @code{private-key}
31182 Use the specific @var{file}s as the public/private key pair used to sign
31183 the store items being published.
31188 At least one remote worker must also be started on any machine of the
31189 local network to actually perform the builds and report their status.
31191 @deftp {Data Type} cuirass-remote-worker-configuration
31192 Data type representing the configuration of the Cuirass remote-worker.
31195 @item @code{cuirass} (default: @code{cuirass})
31196 The Cuirass package to use.
31198 @item @code{workers} (default: @code{1})
31199 Start @var{workers} parallel workers.
31201 @item @code{server} (default: @code{#f})
31202 Do not use Avahi discovery and connect to the given @code{server} IP
31205 @item @code{systems} (default: @code{(list (%current-system))})
31206 Only request builds for the given @var{systems}.
31208 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-worker.log"})
31209 Location of the log file.
31211 @item @code{publish-port} (default: @code{5558})
31212 The TCP port of the publish server. It defaults to @code{5558}.
31214 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
31215 The list of URLs where to look for substitutes by default.
31217 @item @code{public-key}
31218 @item @code{private-key}
31219 Use the specific @var{file}s as the public/private key pair used to sign
31220 the store items being published.
31225 @subsubheading Laminar
31227 @uref{https://laminar.ohwg.net/, Laminar} is a lightweight and modular
31228 Continuous Integration service. It doesn't have a configuration web UI
31229 instead uses version-controllable configuration files and scripts.
31231 Laminar encourages the use of existing tools such as bash and cron
31232 instead of reinventing them.
31234 @defvr {Scheme Procedure} laminar-service-type
31235 The type of the Laminar service. Its value must be a
31236 @code{laminar-configuration} object, as described below.
31238 All configuration values have defaults, a minimal configuration to get
31239 Laminar running is shown below. By default, the web interface is
31240 available on port 8080.
31243 (service laminar-service-type)
31247 @deftp {Data Type} laminar-configuration
31248 Data type representing the configuration of Laminar.
31251 @item @code{laminar} (default: @code{laminar})
31252 The Laminar package to use.
31254 @item @code{home-directory} (default: @code{"/var/lib/laminar"})
31255 The directory for job configurations and run directories.
31257 @item @code{bind-http} (default: @code{"*:8080"})
31258 The interface/port or unix socket on which laminard should listen for
31259 incoming connections to the web frontend.
31261 @item @code{bind-rpc} (default: @code{"unix-abstract:laminar"})
31262 The interface/port or unix socket on which laminard should listen for
31263 incoming commands such as build triggers.
31265 @item @code{title} (default: @code{"Laminar"})
31266 The page title to show in the web frontend.
31268 @item @code{keep-rundirs} (default: @code{0})
31269 Set to an integer defining how many rundirs to keep per job. The
31270 lowest-numbered ones will be deleted. The default is 0, meaning all run
31271 dirs will be immediately deleted.
31273 @item @code{archive-url} (default: @code{#f})
31274 The web frontend served by laminard will use this URL to form links to
31275 artefacts archived jobs.
31277 @item @code{base-url} (default: @code{#f})
31278 Base URL to use for links to laminar itself.
31283 @node Power Management Services
31284 @subsection Power Management Services
31287 @cindex power management with TLP
31288 @subsubheading TLP daemon
31290 The @code{(gnu services pm)} module provides a Guix service definition
31291 for the Linux power management tool TLP.
31293 TLP enables various powersaving modes in userspace and kernel.
31294 Contrary to @code{upower-service}, it is not a passive,
31295 monitoring tool, as it will apply custom settings each time a new power
31296 source is detected. More information can be found at
31297 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
31299 @deffn {Scheme Variable} tlp-service-type
31300 The service type for the TLP tool. The default settings are optimised
31301 for battery life on most systems, but you can tweak them to your heart's
31302 content by adding a valid @code{tlp-configuration}:
31304 (service tlp-service-type
31306 (cpu-scaling-governor-on-ac (list "performance"))
31307 (sched-powersave-on-bat? #t)))
31311 Each parameter definition is preceded by its type; for example,
31312 @samp{boolean foo} indicates that the @code{foo} parameter should be
31313 specified as a boolean. Types starting with @code{maybe-} denote
31314 parameters that won't show up in TLP config file when their value is
31315 left unset, or is explicitly set to the @code{'unset} value.
31317 @c The following documentation was initially generated by
31318 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
31319 @c documentation is better, so we shouldn't hesitate to edit below as
31320 @c needed. However if the change you want to make to this documentation
31321 @c can be done in an automated way, it's probably easier to change
31322 @c (generate-documentation) than to make it below and have to deal with
31323 @c the churn as TLP updates.
31325 Available @code{tlp-configuration} fields are:
31327 @deftypevr {@code{tlp-configuration} parameter} package tlp
31332 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
31333 Set to true if you wish to enable TLP.
31335 Defaults to @samp{#t}.
31339 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
31340 Default mode when no power supply can be detected. Alternatives are AC
31343 Defaults to @samp{"AC"}.
31347 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
31348 Number of seconds Linux kernel has to wait after the disk goes idle,
31349 before syncing on AC.
31351 Defaults to @samp{0}.
31355 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
31356 Same as @code{disk-idle-ac} but on BAT mode.
31358 Defaults to @samp{2}.
31362 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
31363 Dirty pages flushing periodicity, expressed in seconds.
31365 Defaults to @samp{15}.
31369 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
31370 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
31372 Defaults to @samp{60}.
31376 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
31377 CPU frequency scaling governor on AC mode. With intel_pstate driver,
31378 alternatives are powersave and performance. With acpi-cpufreq driver,
31379 alternatives are ondemand, powersave, performance and conservative.
31381 Defaults to @samp{disabled}.
31385 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
31386 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
31388 Defaults to @samp{disabled}.
31392 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
31393 Set the min available frequency for the scaling governor on AC.
31395 Defaults to @samp{disabled}.
31399 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
31400 Set the max available frequency for the scaling governor on AC.
31402 Defaults to @samp{disabled}.
31406 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
31407 Set the min available frequency for the scaling governor on BAT.
31409 Defaults to @samp{disabled}.
31413 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
31414 Set the max available frequency for the scaling governor on BAT.
31416 Defaults to @samp{disabled}.
31420 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
31421 Limit the min P-state to control the power dissipation of the CPU, in AC
31422 mode. Values are stated as a percentage of the available performance.
31424 Defaults to @samp{disabled}.
31428 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
31429 Limit the max P-state to control the power dissipation of the CPU, in AC
31430 mode. Values are stated as a percentage of the available performance.
31432 Defaults to @samp{disabled}.
31436 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
31437 Same as @code{cpu-min-perf-on-ac} on BAT mode.
31439 Defaults to @samp{disabled}.
31443 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
31444 Same as @code{cpu-max-perf-on-ac} on BAT mode.
31446 Defaults to @samp{disabled}.
31450 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
31451 Enable CPU turbo boost feature on AC mode.
31453 Defaults to @samp{disabled}.
31457 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
31458 Same as @code{cpu-boost-on-ac?} on BAT mode.
31460 Defaults to @samp{disabled}.
31464 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
31465 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
31466 used under light load conditions.
31468 Defaults to @samp{#f}.
31472 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
31473 Same as @code{sched-powersave-on-ac?} but on BAT mode.
31475 Defaults to @samp{#t}.
31479 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
31480 Enable Linux kernel NMI watchdog.
31482 Defaults to @samp{#f}.
31486 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
31487 For Linux kernels with PHC patch applied, change CPU voltages. An
31488 example value would be @samp{"F:V F:V F:V F:V"}.
31490 Defaults to @samp{disabled}.
31494 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
31495 Set CPU performance versus energy saving policy on AC@. Alternatives are
31496 performance, normal, powersave.
31498 Defaults to @samp{"performance"}.
31502 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
31503 Same as @code{energy-perf-policy-ac} but on BAT mode.
31505 Defaults to @samp{"powersave"}.
31509 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
31514 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
31515 Hard disk advanced power management level.
31519 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
31520 Same as @code{disk-apm-bat} but on BAT mode.
31524 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
31525 Hard disk spin down timeout. One value has to be specified for each
31526 declared hard disk.
31528 Defaults to @samp{disabled}.
31532 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
31533 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
31535 Defaults to @samp{disabled}.
31539 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
31540 Select IO scheduler for disk devices. One value has to be specified for
31541 each declared hard disk. Example alternatives are cfq, deadline and
31544 Defaults to @samp{disabled}.
31548 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
31549 SATA aggressive link power management (ALPM) level. Alternatives are
31550 min_power, medium_power, max_performance.
31552 Defaults to @samp{"max_performance"}.
31556 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
31557 Same as @code{sata-linkpwr-ac} but on BAT mode.
31559 Defaults to @samp{"min_power"}.
31563 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
31564 Exclude specified SATA host devices for link power management.
31566 Defaults to @samp{disabled}.
31570 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
31571 Enable Runtime Power Management for AHCI controller and disks on AC
31574 Defaults to @samp{disabled}.
31578 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
31579 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
31581 Defaults to @samp{disabled}.
31585 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
31586 Seconds of inactivity before disk is suspended.
31588 Defaults to @samp{15}.
31592 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
31593 PCI Express Active State Power Management level. Alternatives are
31594 default, performance, powersave.
31596 Defaults to @samp{"performance"}.
31600 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
31601 Same as @code{pcie-aspm-ac} but on BAT mode.
31603 Defaults to @samp{"powersave"}.
31607 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat0
31608 Percentage when battery 0 should begin charging. Only supported on some laptops.
31610 Defaults to @samp{disabled}.
31614 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat0
31615 Percentage when battery 0 should stop charging. Only supported on some laptops.
31617 Defaults to @samp{disabled}.
31621 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat1
31622 Percentage when battery 1 should begin charging. Only supported on some laptops.
31624 Defaults to @samp{disabled}.
31628 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat1
31629 Percentage when battery 1 should stop charging. Only supported on some laptops.
31631 Defaults to @samp{disabled}.
31635 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
31636 Radeon graphics clock speed level. Alternatives are low, mid, high,
31639 Defaults to @samp{"high"}.
31643 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
31644 Same as @code{radeon-power-ac} but on BAT mode.
31646 Defaults to @samp{"low"}.
31650 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
31651 Radeon dynamic power management method (DPM). Alternatives are battery,
31654 Defaults to @samp{"performance"}.
31658 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
31659 Same as @code{radeon-dpm-state-ac} but on BAT mode.
31661 Defaults to @samp{"battery"}.
31665 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
31666 Radeon DPM performance level. Alternatives are auto, low, high.
31668 Defaults to @samp{"auto"}.
31672 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
31673 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
31675 Defaults to @samp{"auto"}.
31679 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
31680 Wifi power saving mode.
31682 Defaults to @samp{#f}.
31686 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
31687 Same as @code{wifi-power-ac?} but on BAT mode.
31689 Defaults to @samp{#t}.
31693 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
31694 Disable wake on LAN.
31696 Defaults to @samp{#t}.
31700 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
31701 Timeout duration in seconds before activating audio power saving on
31702 Intel HDA and AC97 devices. A value of 0 disables power saving.
31704 Defaults to @samp{0}.
31708 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
31709 Same as @code{sound-powersave-ac} but on BAT mode.
31711 Defaults to @samp{1}.
31715 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
31716 Disable controller in powersaving mode on Intel HDA devices.
31718 Defaults to @samp{#t}.
31722 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
31723 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
31724 powered on again by releasing (and reinserting) the eject lever or by
31725 pressing the disc eject button on newer models.
31727 Defaults to @samp{#f}.
31731 @deftypevr {@code{tlp-configuration} parameter} string bay-device
31732 Name of the optical drive device to power off.
31734 Defaults to @samp{"sr0"}.
31738 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
31739 Runtime Power Management for PCI(e) bus devices. Alternatives are on
31742 Defaults to @samp{"on"}.
31746 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
31747 Same as @code{runtime-pm-ac} but on BAT mode.
31749 Defaults to @samp{"auto"}.
31753 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
31754 Runtime Power Management for all PCI(e) bus devices, except blacklisted
31757 Defaults to @samp{#t}.
31761 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
31762 Exclude specified PCI(e) device addresses from Runtime Power Management.
31764 Defaults to @samp{disabled}.
31768 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
31769 Exclude PCI(e) devices assigned to the specified drivers from Runtime
31774 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
31775 Enable USB autosuspend feature.
31777 Defaults to @samp{#t}.
31781 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
31782 Exclude specified devices from USB autosuspend.
31784 Defaults to @samp{disabled}.
31788 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
31789 Exclude WWAN devices from USB autosuspend.
31791 Defaults to @samp{#t}.
31795 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
31796 Include specified devices into USB autosuspend, even if they are already
31797 excluded by the driver or via @code{usb-blacklist-wwan?}.
31799 Defaults to @samp{disabled}.
31803 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
31804 Enable USB autosuspend before shutdown.
31806 Defaults to @samp{disabled}.
31810 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
31811 Restore radio device state (bluetooth, wifi, wwan) from previous
31812 shutdown on system startup.
31814 Defaults to @samp{#f}.
31819 @cindex CPU frequency scaling with thermald
31820 @subsubheading Thermald daemon
31822 The @code{(gnu services pm)} module provides an interface to
31823 thermald, a CPU frequency scaling service which helps prevent overheating.
31825 @defvr {Scheme Variable} thermald-service-type
31826 This is the service type for
31827 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
31828 Thermal Daemon, which is responsible for controlling the thermal state
31829 of processors and preventing overheating.
31832 @deftp {Data Type} thermald-configuration
31833 Data type representing the configuration of @code{thermald-service-type}.
31836 @item @code{adaptive?} (default: @code{#f})
31837 Use @acronym{DPTF, Dynamic Power and Thermal Framework} adaptive tables
31840 @item @code{ignore-cpuid-check?} (default: @code{#f})
31841 Ignore cpuid check for supported CPU models.
31843 @item @code{thermald} (default: @var{thermald})
31844 Package object of thermald.
31849 @node Audio Services
31850 @subsection Audio Services
31852 The @code{(gnu services audio)} module provides a service to start MPD
31853 (the Music Player Daemon).
31856 @subsubheading Music Player Daemon
31858 The Music Player Daemon (MPD) is a service that can play music while
31859 being controlled from the local machine or over the network by a variety
31862 The following example shows how one might run @code{mpd} as user
31863 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
31866 (service mpd-service-type
31872 @defvr {Scheme Variable} mpd-service-type
31873 The service type for @command{mpd}
31876 @deftp {Data Type} mpd-configuration
31877 Data type representing the configuration of @command{mpd}.
31880 @item @code{user} (default: @code{"mpd"})
31881 The user to run mpd as.
31883 @item @code{music-dir} (default: @code{"~/Music"})
31884 The directory to scan for music files.
31886 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
31887 The directory to store playlists.
31889 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
31890 The location of the music database.
31892 @item @code{state-file} (default: @code{"~/.mpd/state"})
31893 The location of the file that stores current MPD's state.
31895 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
31896 The location of the sticker database.
31898 @item @code{port} (default: @code{"6600"})
31899 The port to run mpd on.
31901 @item @code{address} (default: @code{"any"})
31902 The address that mpd will bind to. To use a Unix domain socket,
31903 an absolute path can be specified here.
31905 @item @code{outputs} (default: @code{"(list (mpd-output))"})
31906 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
31911 @deftp {Data Type} mpd-output
31912 Data type representing an @command{mpd} audio output.
31915 @item @code{name} (default: @code{"MPD"})
31916 The name of the audio output.
31918 @item @code{type} (default: @code{"pulse"})
31919 The type of audio output.
31921 @item @code{enabled?} (default: @code{#t})
31922 Specifies whether this audio output is enabled when MPD is started. By
31923 default, all audio outputs are enabled. This is just the default
31924 setting when there is no state file; with a state file, the previous
31927 @item @code{tags?} (default: @code{#t})
31928 If set to @code{#f}, then MPD will not send tags to this output. This
31929 is only useful for output plugins that can receive tags, for example the
31930 @code{httpd} output plugin.
31932 @item @code{always-on?} (default: @code{#f})
31933 If set to @code{#t}, then MPD attempts to keep this audio output always
31934 open. This may be useful for streaming servers, when you don’t want to
31935 disconnect all listeners even when playback is accidentally stopped.
31937 @item @code{mixer-type}
31938 This field accepts a symbol that specifies which mixer should be used
31939 for this audio output: the @code{hardware} mixer, the @code{software}
31940 mixer, the @code{null} mixer (allows setting the volume, but with no
31941 effect; this can be used as a trick to implement an external mixer
31942 External Mixer) or no mixer (@code{none}).
31944 @item @code{extra-options} (default: @code{'()})
31945 An association list of option symbols to string values to be appended to
31946 the audio output configuration.
31951 The following example shows a configuration of @code{mpd} that provides
31952 an HTTP audio streaming output.
31955 (service mpd-service-type
31963 `((encoder . "vorbis")
31964 (port . "8080"))))))))
31968 @node Virtualization Services
31969 @subsection Virtualization Services
31971 The @code{(gnu services virtualization)} module provides services for
31972 the libvirt and virtlog daemons, as well as other virtualization-related
31975 @subsubheading Libvirt daemon
31977 @code{libvirtd} is the server side daemon component of the libvirt
31978 virtualization management system. This daemon runs on host servers
31979 and performs required management tasks for virtualized guests.
31981 @deffn {Scheme Variable} libvirt-service-type
31982 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
31983 Its value must be a @code{libvirt-configuration}.
31986 (service libvirt-service-type
31987 (libvirt-configuration
31988 (unix-sock-group "libvirt")
31989 (tls-port "16555")))
31993 @c Auto-generated with (generate-libvirt-documentation)
31994 Available @code{libvirt-configuration} fields are:
31996 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
32001 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
32002 Flag listening for secure TLS connections on the public TCP/IP port.
32003 You must set @code{listen} for this to have any effect.
32005 It is necessary to setup a CA and issue server certificates before using
32008 Defaults to @samp{#t}.
32012 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
32013 Listen for unencrypted TCP connections on the public TCP/IP port. You must
32014 set @code{listen} for this to have any effect.
32016 Using the TCP socket requires SASL authentication by default. Only SASL
32017 mechanisms which support data encryption are allowed. This is
32018 DIGEST_MD5 and GSSAPI (Kerberos5).
32020 Defaults to @samp{#f}.
32024 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
32025 Port for accepting secure TLS connections. This can be a port number,
32028 Defaults to @samp{"16514"}.
32032 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
32033 Port for accepting insecure TCP connections. This can be a port number,
32036 Defaults to @samp{"16509"}.
32040 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
32041 IP address or hostname used for client connections.
32043 Defaults to @samp{"0.0.0.0"}.
32047 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
32048 Flag toggling mDNS advertisement of the libvirt service.
32050 Alternatively can disable for all services on a host by stopping the
32053 Defaults to @samp{#f}.
32057 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
32058 Default mDNS advertisement name. This must be unique on the immediate
32061 Defaults to @samp{"Virtualization Host <hostname>"}.
32065 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
32066 UNIX domain socket group ownership. This can be used to allow a
32067 'trusted' set of users access to management capabilities without
32070 Defaults to @samp{"root"}.
32074 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
32075 UNIX socket permissions for the R/O socket. This is used for monitoring
32078 Defaults to @samp{"0777"}.
32082 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
32083 UNIX socket permissions for the R/W socket. Default allows only root.
32084 If PolicyKit is enabled on the socket, the default will change to allow
32085 everyone (eg, 0777)
32087 Defaults to @samp{"0770"}.
32091 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
32092 UNIX socket permissions for the admin socket. Default allows only owner
32093 (root), do not change it unless you are sure to whom you are exposing
32096 Defaults to @samp{"0777"}.
32100 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
32101 The directory in which sockets will be found/created.
32103 Defaults to @samp{"/var/run/libvirt"}.
32107 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
32108 Authentication scheme for UNIX read-only sockets. By default socket
32109 permissions allow anyone to connect
32111 Defaults to @samp{"polkit"}.
32115 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
32116 Authentication scheme for UNIX read-write sockets. By default socket
32117 permissions only allow root. If PolicyKit support was compiled into
32118 libvirt, the default will be to use 'polkit' auth.
32120 Defaults to @samp{"polkit"}.
32124 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
32125 Authentication scheme for TCP sockets. If you don't enable SASL, then
32126 all TCP traffic is cleartext. Don't do this outside of a dev/test
32129 Defaults to @samp{"sasl"}.
32133 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
32134 Authentication scheme for TLS sockets. TLS sockets already have
32135 encryption provided by the TLS layer, and limited authentication is done
32138 It is possible to make use of any SASL authentication mechanism as well,
32139 by using 'sasl' for this option
32141 Defaults to @samp{"none"}.
32145 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
32146 API access control scheme.
32148 By default an authenticated user is allowed access to all APIs. Access
32149 drivers can place restrictions on this.
32151 Defaults to @samp{()}.
32155 @deftypevr {@code{libvirt-configuration} parameter} string key-file
32156 Server key file path. If set to an empty string, then no private key is
32159 Defaults to @samp{""}.
32163 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
32164 Server key file path. If set to an empty string, then no certificate is
32167 Defaults to @samp{""}.
32171 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
32172 Server key file path. If set to an empty string, then no CA certificate
32175 Defaults to @samp{""}.
32179 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
32180 Certificate revocation list path. If set to an empty string, then no
32183 Defaults to @samp{""}.
32187 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
32188 Disable verification of our own server certificates.
32190 When libvirtd starts it performs some sanity checks against its own
32193 Defaults to @samp{#f}.
32197 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
32198 Disable verification of client certificates.
32200 Client certificate verification is the primary authentication mechanism.
32201 Any client which does not present a certificate signed by the CA will be
32204 Defaults to @samp{#f}.
32208 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
32209 Whitelist of allowed x509 Distinguished Name.
32211 Defaults to @samp{()}.
32215 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
32216 Whitelist of allowed SASL usernames. The format for username depends on
32217 the SASL authentication mechanism.
32219 Defaults to @samp{()}.
32223 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
32224 Override the compile time default TLS priority string. The default is
32225 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
32226 is desired for libvirt to deviate from the global default settings.
32228 Defaults to @samp{"NORMAL"}.
32232 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
32233 Maximum number of concurrent client connections to allow over all
32236 Defaults to @samp{5000}.
32240 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
32241 Maximum length of queue of connections waiting to be accepted by the
32242 daemon. Note, that some protocols supporting retransmission may obey
32243 this so that a later reattempt at connection succeeds.
32245 Defaults to @samp{1000}.
32249 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
32250 Maximum length of queue of accepted but not yet authenticated clients.
32251 Set this to zero to turn this feature off
32253 Defaults to @samp{20}.
32257 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
32258 Number of workers to start up initially.
32260 Defaults to @samp{5}.
32264 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
32265 Maximum number of worker threads.
32267 If the number of active clients exceeds @code{min-workers}, then more
32268 threads are spawned, up to max_workers limit. Typically you'd want
32269 max_workers to equal maximum number of clients allowed.
32271 Defaults to @samp{20}.
32275 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
32276 Number of priority workers. If all workers from above pool are stuck,
32277 some calls marked as high priority (notably domainDestroy) can be
32278 executed in this pool.
32280 Defaults to @samp{5}.
32284 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
32285 Total global limit on concurrent RPC calls.
32287 Defaults to @samp{20}.
32291 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
32292 Limit on concurrent requests from a single client connection. To avoid
32293 one client monopolizing the server this should be a small fraction of
32294 the global max_requests and max_workers parameter.
32296 Defaults to @samp{5}.
32300 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
32301 Same as @code{min-workers} but for the admin interface.
32303 Defaults to @samp{1}.
32307 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
32308 Same as @code{max-workers} but for the admin interface.
32310 Defaults to @samp{5}.
32314 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
32315 Same as @code{max-clients} but for the admin interface.
32317 Defaults to @samp{5}.
32321 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
32322 Same as @code{max-queued-clients} but for the admin interface.
32324 Defaults to @samp{5}.
32328 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
32329 Same as @code{max-client-requests} but for the admin interface.
32331 Defaults to @samp{5}.
32335 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
32336 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32338 Defaults to @samp{3}.
32342 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
32345 A filter allows to select a different logging level for a given category
32346 of logs. The format for a filter is one of:
32357 where @code{name} is a string which is matched against the category
32358 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32359 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
32360 name in the filter can be a substring of the full category name, in
32361 order to match multiple similar categories), the optional @samp{"+"}
32362 prefix tells libvirt to log stack trace for each message matching name,
32363 and @code{x} is the minimal level where matching messages should be
32381 Multiple filters can be defined in a single filters statement, they just
32382 need to be separated by spaces.
32384 Defaults to @samp{"3:remote 4:event"}.
32388 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
32391 An output is one of the places to save logging information. The format
32392 for an output can be:
32396 output goes to stderr
32398 @item x:syslog:name
32399 use syslog for the output and use the given name as the ident
32401 @item x:file:file_path
32402 output to a file, with the given filepath
32405 output to journald logging system
32409 In all case the x prefix is the minimal level, acting as a filter
32426 Multiple outputs can be defined, they just need to be separated by
32429 Defaults to @samp{"3:stderr"}.
32433 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
32434 Allows usage of the auditing subsystem to be altered
32438 0: disable all auditing
32441 1: enable auditing, only if enabled on host
32444 2: enable auditing, and exit if disabled on host.
32448 Defaults to @samp{1}.
32452 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
32453 Send audit messages via libvirt logging infrastructure.
32455 Defaults to @samp{#f}.
32459 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
32460 Host UUID@. UUID must not have all digits be the same.
32462 Defaults to @samp{""}.
32466 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
32467 Source to read host UUID.
32471 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
32474 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
32478 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
32481 Defaults to @samp{"smbios"}.
32485 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
32486 A keepalive message is sent to a client after @code{keepalive_interval}
32487 seconds of inactivity to check if the client is still responding. If
32488 set to -1, libvirtd will never send keepalive requests; however clients
32489 can still send them and the daemon will send responses.
32491 Defaults to @samp{5}.
32495 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
32496 Maximum number of keepalive messages that are allowed to be sent to the
32497 client without getting any response before the connection is considered
32500 In other words, the connection is automatically closed approximately
32501 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
32502 the last message received from the client. When @code{keepalive-count}
32503 is set to 0, connections will be automatically closed after
32504 @code{keepalive-interval} seconds of inactivity without sending any
32505 keepalive messages.
32507 Defaults to @samp{5}.
32511 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
32512 Same as above but for admin interface.
32514 Defaults to @samp{5}.
32518 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
32519 Same as above but for admin interface.
32521 Defaults to @samp{5}.
32525 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
32526 Timeout for Open vSwitch calls.
32528 The @code{ovs-vsctl} utility is used for the configuration and its
32529 timeout option is set by default to 5 seconds to avoid potential
32530 infinite waits blocking libvirt.
32532 Defaults to @samp{5}.
32536 @c %end of autogenerated docs
32538 @subsubheading Virtlog daemon
32539 The virtlogd service is a server side daemon component of libvirt that is
32540 used to manage logs from virtual machine consoles.
32542 This daemon is not used directly by libvirt client applications, rather it
32543 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
32544 standalone daemon, the main @code{libvirtd} daemon can be restarted without
32545 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
32546 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
32548 @deffn {Scheme Variable} virtlog-service-type
32549 This is the type of the virtlog daemon.
32550 Its value must be a @code{virtlog-configuration}.
32553 (service virtlog-service-type
32554 (virtlog-configuration
32555 (max-clients 1000)))
32559 @deftypevar {@code{libvirt} parameter} package libvirt
32563 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
32564 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32566 Defaults to @samp{3}.
32570 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
32573 A filter allows to select a different logging level for a given category
32574 of logs The format for a filter is one of:
32585 where @code{name} is a string which is matched against the category
32586 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32587 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
32588 be a substring of the full category name, in order to match multiple
32589 similar categories), the optional "+" prefix tells libvirt to log stack
32590 trace for each message matching name, and @code{x} is the minimal level
32591 where matching messages should be logged:
32608 Multiple filters can be defined in a single filters statement, they just
32609 need to be separated by spaces.
32611 Defaults to @samp{"3:remote 4:event"}.
32615 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
32618 An output is one of the places to save logging information The format
32619 for an output can be:
32623 output goes to stderr
32625 @item x:syslog:name
32626 use syslog for the output and use the given name as the ident
32628 @item x:file:file_path
32629 output to a file, with the given filepath
32632 output to journald logging system
32636 In all case the x prefix is the minimal level, acting as a filter
32653 Multiple outputs can be defined, they just need to be separated by
32656 Defaults to @samp{"3:stderr"}.
32660 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
32661 Maximum number of concurrent client connections to allow over all
32664 Defaults to @samp{1024}.
32668 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
32669 Maximum file size before rolling over.
32671 Defaults to @samp{2MB}
32675 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
32676 Maximum number of backup files to keep.
32678 Defaults to @samp{3}
32682 @anchor{transparent-emulation-qemu}
32683 @subsubheading Transparent Emulation with QEMU
32686 @cindex @code{binfmt_misc}
32687 @code{qemu-binfmt-service-type} provides support for transparent
32688 emulation of program binaries built for different architectures---e.g.,
32689 it allows you to transparently execute an ARMv7 program on an x86_64
32690 machine. It achieves this by combining the @uref{https://www.qemu.org,
32691 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
32692 This feature only allows you to emulate GNU/Linux on a different
32693 architecture, but see below for GNU/Hurd support.
32695 @defvr {Scheme Variable} qemu-binfmt-service-type
32696 This is the type of the QEMU/binfmt service for transparent emulation.
32697 Its value must be a @code{qemu-binfmt-configuration} object, which
32698 specifies the QEMU package to use as well as the architecture we want to
32702 (service qemu-binfmt-service-type
32703 (qemu-binfmt-configuration
32704 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
32707 In this example, we enable transparent emulation for the ARM and aarch64
32708 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
32709 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
32710 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
32713 @deftp {Data Type} qemu-binfmt-configuration
32714 This is the configuration for the @code{qemu-binfmt} service.
32717 @item @code{platforms} (default: @code{'()})
32718 The list of emulated QEMU platforms. Each item must be a @dfn{platform
32719 object} as returned by @code{lookup-qemu-platforms} (see below).
32721 For example, let's suppose you're on an x86_64 machine and you have this
32725 (service qemu-binfmt-service-type
32726 (qemu-binfmt-configuration
32727 (platforms (lookup-qemu-platforms "arm"))))
32733 guix build -s armhf-linux inkscape
32737 and it will build Inkscape for ARMv7 @emph{as if it were a native
32738 build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
32739 if you'd like to test a package build for an architecture you don't have
32742 @item @code{qemu} (default: @code{qemu})
32743 The QEMU package to use.
32747 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
32748 Return the list of QEMU platform objects corresponding to
32749 @var{platforms}@dots{}. @var{platforms} must be a list of strings
32750 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
32751 @code{"mips64el"}, and so on.
32754 @deffn {Scheme Procedure} qemu-platform? @var{obj}
32755 Return true if @var{obj} is a platform object.
32758 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
32759 Return the name of @var{platform}---a string such as @code{"arm"}.
32763 @subsubheading QEMU Guest Agent
32767 The QEMU guest agent provides control over the emulated system to the
32768 host. The @code{qemu-guest-agent} service runs the agent on Guix
32769 guests. To control the agent from the host, open a socket by invoking
32770 QEMU with the following arguments:
32773 qemu-system-x86_64 \
32774 -chardev socket,path=/tmp/qga.sock,server=on,wait=off,id=qga0 \
32775 -device virtio-serial \
32776 -device virtserialport,chardev=qga0,name=org.qemu.guest_agent.0 \
32780 This creates a socket at @file{/tmp/qga.sock} on the host. Once the
32781 guest agent is running, you can issue commands with @code{socat}:
32784 $ guix shell socat -- socat unix-connect:/tmp/qga.sock stdio
32785 @{"execute": "guest-get-host-name"@}
32786 @{"return": @{"host-name": "guix"@}@}
32789 See @url{https://wiki.qemu.org/Features/GuestAgent,QEMU guest agent
32790 documentation} for more options and commands.
32792 @defvr {Scheme Variable} qemu-guest-agent-service-type
32793 Service type for the QEMU guest agent service.
32796 @deftp {Data Type} qemu-guest-agent-configuration
32797 Configuration for the @code{qemu-guest-agent} service.
32800 @item @code{qemu} (default: @code{qemu-minimal})
32801 The QEMU package to use.
32803 @item @code{device} (default: @code{""})
32804 File name of the device or socket the agent uses to communicate with the
32805 host. If empty, QEMU uses a default file name.
32810 @subsubheading The Hurd in a Virtual Machine
32812 @cindex @code{hurd}
32816 Service @code{hurd-vm} provides support for running GNU/Hurd in a
32817 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
32818 to be used on GNU/Linux and the given GNU/Hurd operating system
32819 configuration is cross-compiled. The virtual machine is a Shepherd
32820 service that can be referred to by the names @code{hurd-vm} and
32821 @code{childhurd} and be controlled with commands such as:
32825 herd stop childhurd
32828 When the service is running, you can view its console by connecting to
32829 it with a VNC client, for example with:
32832 guix shell tigervnc-client -- vncviewer localhost:5900
32835 The default configuration (see @code{hurd-vm-configuration} below)
32836 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
32837 (the virtual machine emulator) redirects to port 10222 on the host.
32838 Thus, you can connect over SSH to the childhurd with:
32841 ssh root@@localhost -p 10022
32844 The childhurd is volatile and stateless: it starts with a fresh root
32845 file system every time you restart it. By default though, all the files
32846 under @file{/etc/childhurd} on the host are copied as is to the root
32847 file system of the childhurd when it boots. This allows you to
32848 initialize ``secrets'' inside the VM: SSH host keys, authorized
32849 substitute keys, and so on---see the explanation of @code{secret-root}
32852 @defvr {Scheme Variable} hurd-vm-service-type
32853 This is the type of the Hurd in a Virtual Machine service. Its value
32854 must be a @code{hurd-vm-configuration} object, which specifies the
32855 operating system (@pxref{operating-system Reference}) and the disk size
32856 for the Hurd Virtual Machine, the QEMU package to use as well as the
32857 options for running it.
32862 (service hurd-vm-service-type
32863 (hurd-vm-configuration
32864 (disk-size (* 5000 (expt 2 20))) ;5G
32865 (memory-size 1024))) ;1024MiB
32868 would create a disk image big enough to build GNU@tie{}Hello, with some
32872 @deftp {Data Type} hurd-vm-configuration
32873 The data type representing the configuration for
32874 @code{hurd-vm-service-type}.
32877 @item @code{os} (default: @var{%hurd-vm-operating-system})
32878 The operating system to instantiate. This default is bare-bones with a
32879 permissive OpenSSH secure shell daemon listening on port 2222
32880 (@pxref{Networking Services, @code{openssh-service-type}}).
32882 @item @code{qemu} (default: @code{qemu-minimal})
32883 The QEMU package to use.
32885 @item @code{image} (default: @var{hurd-vm-disk-image})
32886 The procedure used to build the disk-image built from this
32889 @item @code{disk-size} (default: @code{'guess})
32890 The size of the disk image.
32892 @item @code{memory-size} (default: @code{512})
32893 The memory size of the Virtual Machine in mebibytes.
32895 @item @code{options} (default: @code{'("--snapshot")})
32896 The extra options for running QEMU.
32898 @item @code{id} (default: @code{#f})
32899 If set, a non-zero positive integer used to parameterize Childhurd
32900 instances. It is appended to the service's name,
32901 e.g. @code{childhurd1}.
32903 @item @code{net-options} (default: @var{hurd-vm-net-options})
32904 The procedure used to produce the list of QEMU networking options.
32906 By default, it produces
32909 '("--device" "rtl8139,netdev=net0"
32910 "--netdev" (string-append
32912 "hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004,"
32913 "hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222,"
32914 "hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900"))
32917 with forwarded ports:
32920 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
32921 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
32922 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
32925 @item @code{secret-root} (default: @file{/etc/childhurd})
32926 The root directory with out-of-band secrets to be installed into the
32927 childhurd once it runs. Childhurds are volatile which means that on
32928 every startup, secrets such as the SSH host keys and Guix signing key
32931 If the @file{/etc/childhurd} directory does not exist, the
32932 @code{secret-service} running in the Childhurd will be sent an empty
32935 By default, the service automatically populates @file{/etc/childhurd}
32936 with the following non-volatile secrets, unless they already exist:
32939 /etc/childhurd/etc/guix/acl
32940 /etc/childhurd/etc/guix/signing-key.pub
32941 /etc/childhurd/etc/guix/signing-key.sec
32942 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
32943 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
32944 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
32945 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
32948 These files are automatically sent to the guest Hurd VM when it boots,
32949 including permissions.
32951 @cindex childhurd, offloading
32952 @cindex Hurd, offloading
32953 Having these files in place means that only a couple of things are
32954 missing to allow the host to offload @code{i586-gnu} builds to the
32959 Authorizing the childhurd's key on the host so that the host accepts
32960 build results coming from the childhurd, which can be done like so:
32963 guix archive --authorize < \
32964 /etc/childhurd/etc/guix/signing-key.pub
32968 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
32972 We're working towards making that happen automatically---get in touch
32973 with us at @email{guix-devel@@gnu.org} to discuss it!
32977 Note that by default the VM image is volatile, i.e., once stopped the
32978 contents are lost. If you want a stateful image instead, override the
32979 configuration's @code{image} and @code{options} without
32980 the @code{--snapshot} flag using something along these lines:
32983 (service hurd-vm-service-type
32984 (hurd-vm-configuration
32985 (image (const "/out/of/store/writable/hurd.img"))
32989 @subsubheading Ganeti
32994 This service is considered experimental. Configuration options may be changed
32995 in a backwards-incompatible manner, and not all features have been thorougly
32996 tested. Users of this service are encouraged to share their experience at
32997 @email{guix-devel@@gnu.org}.
33000 Ganeti is a virtual machine management system. It is designed to keep virtual
33001 machines running on a cluster of servers even in the event of hardware failures,
33002 and to make maintenance and recovery tasks easy. It consists of multiple
33003 services which are described later in this section. In addition to the Ganeti
33004 service, you will need the OpenSSH service (@pxref{Networking Services,
33005 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
33006 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
33007 and address (or use a DNS server).
33009 All nodes participating in a Ganeti cluster should have the same Ganeti and
33010 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
33011 cluster node that supports multiple storage backends, and installs the
33012 @code{debootstrap} and @code{guix} @dfn{OS providers}:
33015 (use-package-modules virtualization)
33016 (use-service-modules base ganeti networking ssh)
33019 (host-name "node1")
33020 (hosts-file (plain-file "hosts" (format #f "
33021 127.0.0.1 localhost
33024 192.168.1.200 ganeti.example.com
33025 192.168.1.201 node1.example.com node1
33026 192.168.1.202 node2.example.com node2
33029 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
33030 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
33031 (packages (append (map specification->package
33032 '("qemu" "lvm2" "drbd-utils" "ceph"
33033 ;; Add the debootstrap and guix OS providers.
33034 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
33037 (append (list (service static-networking-service-type
33038 (list (static-networking
33040 (list (network-address
33042 (value "192.168.1.201/24"))))
33044 (list (network-route
33045 (destination "default")
33046 (gateway "192.168.1.254"))))
33047 (name-servers '("192.168.1.252"
33048 "192.168.1.253")))))
33050 ;; Ganeti uses SSH to communicate between nodes.
33051 (service openssh-service-type
33052 (openssh-configuration
33053 (permit-root-login 'prohibit-password)))
33055 (service ganeti-service-type
33056 (ganeti-configuration
33057 ;; This list specifies allowed file system paths
33058 ;; for storing virtual machine images.
33059 (file-storage-paths '("/srv/ganeti/file-storage"))
33060 ;; This variable configures a single "variant" for
33061 ;; both Debootstrap and Guix that works with KVM.
33062 (os %default-ganeti-os))))
33066 Users are advised to read the
33067 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
33068 administrators guide} to learn about the various cluster options and
33069 day-to-day operations. There is also a
33070 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
33071 describing how to configure and initialize a small cluster.
33073 @defvr {Scheme Variable} ganeti-service-type
33074 This is a service type that includes all the various services that Ganeti
33077 Its value is a @code{ganeti-configuration} object that defines the package
33078 to use for CLI operations, as well as configuration for the various daemons.
33079 Allowed file storage paths and available guest operating systems are also
33080 configured through this data type.
33083 @deftp {Data Type} ganeti-configuration
33084 The @code{ganeti} service takes the following configuration options:
33087 @item @code{ganeti} (default: @code{ganeti})
33088 The @code{ganeti} package to use. It will be installed to the system profile
33089 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
33090 that the value specified here does not affect the other services as each refer
33091 to a specific @code{ganeti} package (see below).
33093 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
33094 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
33095 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
33096 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
33097 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
33098 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
33099 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
33100 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
33101 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
33102 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
33104 These options control the various daemons and cron jobs that are distributed
33105 with Ganeti. The possible values for these are described in detail below.
33106 To override a setting, you must use the configuration type for that service:
33109 (service ganeti-service-type
33110 (ganeti-configuration
33111 (rapi-configuration
33112 (ganeti-rapi-configuration
33113 (interface "eth1"))))
33114 (watcher-configuration
33115 (ganeti-watcher-configuration
33116 (rapi-ip "10.0.0.1"))))
33119 @item @code{file-storage-paths} (default: @code{'()})
33120 List of allowed directories for file storage backend.
33122 @item @code{os} (default: @code{%default-ganeti-os})
33123 List of @code{<ganeti-os>} records.
33126 In essence @code{ganeti-service-type} is shorthand for declaring each service
33130 (service ganeti-noded-service-type)
33131 (service ganeti-confd-service-type)
33132 (service ganeti-wconfd-service-type)
33133 (service ganeti-luxid-service-type)
33134 (service ganeti-kvmd-service-type)
33135 (service ganeti-mond-service-type)
33136 (service ganeti-metad-service-type)
33137 (service ganeti-watcher-service-type)
33138 (service ganeti-cleaner-service-type)
33141 Plus a service extension for @code{etc-service-type} that configures the file
33142 storage backend and OS variants.
33146 @deftp {Data Type} ganeti-os
33147 This data type is suitable for passing to the @code{os} parameter of
33148 @code{ganeti-configuration}. It takes the following parameters:
33152 The name for this OS provider. It is only used to specify where the
33153 configuration ends up. Setting it to ``debootstrap'' will create
33154 @file{/etc/ganeti/instance-debootstrap}.
33156 @item @code{extension}
33157 The file extension for variants of this OS type. For example
33158 @file{.conf} or @file{.scm}.
33160 @item @code{variants} (default: @code{'()})
33161 List of @code{ganeti-os-variant} objects for this OS.
33166 @deftp {Data Type} ganeti-os-variant
33167 This is the data type for a Ganeti OS variant. It takes the following
33172 The name of this variant.
33174 @item @code{configuration}
33175 A configuration file for this variant.
33179 @defvr {Scheme Variable} %default-debootstrap-hooks
33180 This variable contains hooks to configure networking and the GRUB bootloader.
33183 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
33184 This variable contains a list of packages suitable for a fully-virtualized guest.
33187 @deftp {Data Type} debootstrap-configuration
33189 This data type creates configuration files suitable for the debootstrap OS provider.
33192 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
33193 When not @code{#f}, this must be a G-expression that specifies a directory with
33194 scripts that will run when the OS is installed. It can also be a list of
33195 @code{(name . file-like)} pairs. For example:
33198 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
33201 That will create a directory with one executable named @code{99-hello-world}
33202 and run it every time this variant is installed. If set to @code{#f}, hooks
33203 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
33204 @item @code{proxy} (default: @code{#f})
33205 Optional HTTP proxy to use.
33206 @item @code{mirror} (default: @code{#f})
33207 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
33208 The default varies depending on the distribution.
33209 @item @code{arch} (default: @code{#f})
33210 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
33211 on an AArch64 host. Default is to use the current system architecture.
33212 @item @code{suite} (default: @code{"stable"})
33213 When set, this must be a Debian distribution ``suite'' such as @code{buster}
33214 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
33215 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
33216 List of extra packages that will get installed by dpkg in addition
33217 to the minimal system.
33218 @item @code{components} (default: @code{#f})
33219 When set, must be a list of Debian repository ``components''. For example
33220 @code{'("main" "contrib")}.
33221 @item @code{generate-cache?} (default: @code{#t})
33222 Whether to automatically cache the generated debootstrap archive.
33223 @item @code{clean-cache} (default: @code{14})
33224 Discard the cache after this amount of days. Use @code{#f} to never
33226 @item @code{partition-style} (default: @code{'msdos})
33227 The type of partition to create. When set, it must be one of
33228 @code{'msdos}, @code{'none} or a string.
33229 @item @code{partition-alignment} (default: @code{2048})
33230 Alignment of the partition in sectors.
33234 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
33235 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
33236 takes two parameters: a name and a @code{debootstrap-configuration} object.
33239 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
33240 This is a helper procedure that creates a @code{ganeti-os} record. It takes
33241 a list of variants created with @code{debootstrap-variant}.
33244 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
33245 This is a helper procedure that creates a @code{ganeti-os-variant} record for
33246 use with the Guix OS provider. It takes a name and a G-expression that returns
33247 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
33248 Guix System configuration.
33251 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
33252 This is a helper procedure that creates a @code{ganeti-os} record. It
33253 takes a list of variants produced by @code{guix-variant}.
33256 @defvr {Scheme Variable} %default-debootstrap-variants
33257 This is a convenience variable to make the debootstrap provider work
33258 ``out of the box'' without users having to declare variants manually. It
33259 contains a single debootstrap variant with the default configuration:
33262 (list (debootstrap-variant
33264 (debootstrap-configuration)))
33268 @defvr {Scheme Variable} %default-guix-variants
33269 This is a convenience variable to make the Guix OS provider work without
33270 additional configuration. It creates a virtual machine that has an SSH
33271 server, a serial console, and authorizes the Ganeti hosts SSH keys.
33274 (list (guix-variant
33276 (file-append ganeti-instance-guix
33277 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
33281 Users can implement support for OS providers unbeknownst to Guix by extending
33282 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
33288 (extension ".conf")
33290 (list (ganeti-os-variant
33292 (configuration (plain-file "bar" "this is fine"))))))
33295 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
33296 to a file in the store with contents @code{this is fine}. It also creates
33297 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
33299 Obviously this may not work for all OS providers out there. If you find the
33300 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
33302 The rest of this section documents the various services that are included by
33303 @code{ganeti-service-type}.
33305 @defvr {Scheme Variable} ganeti-noded-service-type
33306 @command{ganeti-noded} is the daemon responsible for node-specific functions
33307 within the Ganeti system. The value of this service must be a
33308 @code{ganeti-noded-configuration} object.
33311 @deftp {Data Type} ganeti-noded-configuration
33312 This is the configuration for the @code{ganeti-noded} service.
33315 @item @code{ganeti} (default: @code{ganeti})
33316 The @code{ganeti} package to use for this service.
33318 @item @code{port} (default: @code{1811})
33319 The TCP port on which the node daemon listens for network requests.
33321 @item @code{address} (default: @code{"0.0.0.0"})
33322 The network address that the daemon will bind to. The default address means
33323 bind to all available addresses.
33325 @item @code{interface} (default: @code{#f})
33326 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
33327 that the daemon will bind to.
33329 @item @code{max-clients} (default: @code{20})
33330 This sets a limit on the maximum number of simultaneous client connections
33331 that the daemon will handle. Connections above this count are accepted, but
33332 no responses will be sent until enough connections have closed.
33334 @item @code{ssl?} (default: @code{#t})
33335 Whether to use SSL/TLS to encrypt network communications. The certificate
33336 is automatically provisioned by the cluster and can be rotated with
33337 @command{gnt-cluster renew-crypto}.
33339 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33340 This can be used to provide a specific encryption key for TLS communications.
33342 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33343 This can be used to provide a specific certificate for TLS communications.
33345 @item @code{debug?} (default: @code{#f})
33346 When true, the daemon performs additional logging for debugging purposes.
33347 Note that this will leak encryption details to the log files, use with caution.
33352 @defvr {Scheme Variable} ganeti-confd-service-type
33353 @command{ganeti-confd} answers queries related to the configuration of a
33354 Ganeti cluster. The purpose of this daemon is to have a highly available
33355 and fast way to query cluster configuration values. It is automatically
33356 active on all @dfn{master candidates}. The value of this service must be a
33357 @code{ganeti-confd-configuration} object.
33361 @deftp {Data Type} ganeti-confd-configuration
33362 This is the configuration for the @code{ganeti-confd} service.
33365 @item @code{ganeti} (default: @code{ganeti})
33366 The @code{ganeti} package to use for this service.
33368 @item @code{port} (default: @code{1814})
33369 The UDP port on which to listen for network requests.
33371 @item @code{address} (default: @code{"0.0.0.0"})
33372 Network address that the daemon will bind to.
33374 @item @code{debug?} (default: @code{#f})
33375 When true, the daemon performs additional logging for debugging purposes.
33380 @defvr {Scheme Variable} ganeti-wconfd-service-type
33381 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
33382 about the cluster configuration and is the only entity that can accept
33383 changes to it. All jobs that need to modify the configuration will do so
33384 by sending appropriate requests to this daemon. It only runs on the
33385 @dfn{master node} and will automatically disable itself on other nodes.
33387 The value of this service must be a
33388 @code{ganeti-wconfd-configuration} object.
33391 @deftp {Data Type} ganeti-wconfd-configuration
33392 This is the configuration for the @code{ganeti-wconfd} service.
33395 @item @code{ganeti} (default: @code{ganeti})
33396 The @code{ganeti} package to use for this service.
33398 @item @code{no-voting?} (default: @code{#f})
33399 The daemon will refuse to start if the majority of cluster nodes does not
33400 agree that it is running on the master node. Set to @code{#t} to start
33401 even if a quorum can not be reached (dangerous, use with caution).
33403 @item @code{debug?} (default: @code{#f})
33404 When true, the daemon performs additional logging for debugging purposes.
33409 @defvr {Scheme Variable} ganeti-luxid-service-type
33410 @command{ganeti-luxid} is a daemon used to answer queries related to the
33411 configuration and the current live state of a Ganeti cluster. Additionally,
33412 it is the authoritative daemon for the Ganeti job queue. Jobs can be
33413 submitted via this daemon and it schedules and starts them.
33415 It takes a @code{ganeti-luxid-configuration} object.
33418 @deftp {Data Type} ganeti-luxid-configuration
33419 This is the configuration for the @code{ganeti-luxid} service.
33422 @item @code{ganeti} (default: @code{ganeti})
33423 The @code{ganeti} package to use for this service.
33425 @item @code{no-voting?} (default: @code{#f})
33426 The daemon will refuse to start if it cannot verify that the majority of
33427 cluster nodes believes that it is running on the master node. Set to
33428 @code{#t} to ignore such checks and start anyway (this can be dangerous).
33430 @item @code{debug?} (default: @code{#f})
33431 When true, the daemon performs additional logging for debugging purposes.
33436 @defvr {Scheme Variable} ganeti-rapi-service-type
33437 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
33438 the master node and can be used to perform cluster actions programmatically
33439 via a JSON-based RPC protocol.
33441 Most query operations are allowed without authentication (unless
33442 @var{require-authentication?} is set), whereas write operations require
33443 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
33444 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
33445 API documentation} for more information.
33447 The value of this service must be a @code{ganeti-rapi-configuration} object.
33450 @deftp {Data Type} ganeti-rapi-configuration
33451 This is the configuration for the @code{ganeti-rapi} service.
33454 @item @code{ganeti} (default: @code{ganeti})
33455 The @code{ganeti} package to use for this service.
33457 @item @code{require-authentication?} (default: @code{#f})
33458 Whether to require authentication even for read-only operations.
33460 @item @code{port} (default: @code{5080})
33461 The TCP port on which to listen to API requests.
33463 @item @code{address} (default: @code{"0.0.0.0"})
33464 The network address that the service will bind to. By default it listens
33465 on all configured addresses.
33467 @item @code{interface} (default: @code{#f})
33468 When set, it must specify a specific network interface such as @code{eth0}
33469 that the daemon will bind to.
33471 @item @code{max-clients} (default: @code{20})
33472 The maximum number of simultaneous client requests to handle. Further
33473 connections are allowed, but no responses are sent until enough connections
33476 @item @code{ssl?} (default: @code{#t})
33477 Whether to use SSL/TLS encryption on the RAPI port.
33479 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33480 This can be used to provide a specific encryption key for TLS communications.
33482 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33483 This can be used to provide a specific certificate for TLS communications.
33485 @item @code{debug?} (default: @code{#f})
33486 When true, the daemon performs additional logging for debugging purposes.
33487 Note that this will leak encryption details to the log files, use with caution.
33492 @defvr {Scheme Variable} ganeti-kvmd-service-type
33493 @command{ganeti-kvmd} is responsible for determining whether a given KVM
33494 instance was shut down by an administrator or a user. Normally Ganeti will
33495 restart an instance that was not stopped through Ganeti itself. If the
33496 cluster option @code{user_shutdown} is true, this daemon monitors the
33497 @code{QMP} socket provided by QEMU and listens for shutdown events, and
33498 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
33499 it shuts down gracefully by itself.
33501 It takes a @code{ganeti-kvmd-configuration} object.
33504 @deftp {Data Type} ganeti-kvmd-configuration
33507 @item @code{ganeti} (default: @code{ganeti})
33508 The @code{ganeti} package to use for this service.
33510 @item @code{debug?} (default: @code{#f})
33511 When true, the daemon performs additional logging for debugging purposes.
33516 @defvr {Scheme Variable} ganeti-mond-service-type
33517 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
33518 functionality. It is responsible for running data collectors and publish the
33519 collected information through a HTTP interface.
33521 It takes a @code{ganeti-mond-configuration} object.
33524 @deftp {Data Type} ganeti-mond-configuration
33527 @item @code{ganeti} (default: @code{ganeti})
33528 The @code{ganeti} package to use for this service.
33530 @item @code{port} (default: @code{1815})
33531 The port on which the daemon will listen.
33533 @item @code{address} (default: @code{"0.0.0.0"})
33534 The network address that the daemon will bind to. By default it binds to all
33535 available interfaces.
33537 @item @code{debug?} (default: @code{#f})
33538 When true, the daemon performs additional logging for debugging purposes.
33543 @defvr {Scheme Variable} ganeti-metad-service-type
33544 @command{ganeti-metad} is an optional daemon that can be used to provide
33545 information about the cluster to instances or OS install scripts.
33547 It takes a @code{ganeti-metad-configuration} object.
33550 @deftp {Data Type} ganeti-metad-configuration
33553 @item @code{ganeti} (default: @code{ganeti})
33554 The @code{ganeti} package to use for this service.
33556 @item @code{port} (default: @code{80})
33557 The port on which the daemon will listen.
33559 @item @code{address} (default: @code{#f})
33560 If set, the daemon will bind to this address only. If left unset, the behavior
33561 depends on the cluster configuration.
33563 @item @code{debug?} (default: @code{#f})
33564 When true, the daemon performs additional logging for debugging purposes.
33569 @defvr {Scheme Variable} ganeti-watcher-service-type
33570 @command{ganeti-watcher} is a script designed to run periodically and ensure
33571 the health of a cluster. It will automatically restart instances that have
33572 stopped without Ganeti's consent, and repairs DRBD links in case a node has
33573 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
33574 that are not running. If the cluster parameter @code{ensure_node_health}
33575 is set, the watcher will also shutdown instances and DRBD devices if the
33576 node it is running on is declared offline by known master candidates.
33578 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
33580 The service takes a @code{ganeti-watcher-configuration} object.
33583 @deftp {Data Type} ganeti-watcher-configuration
33586 @item @code{ganeti} (default: @code{ganeti})
33587 The @code{ganeti} package to use for this service.
33589 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
33590 How often to run the script. The default is every five minutes.
33592 @item @code{rapi-ip} (default: @code{#f})
33593 This option needs to be specified only if the RAPI daemon is configured to use
33594 a particular interface or address. By default the cluster address is used.
33596 @item @code{job-age} (default: @code{(* 6 3600)})
33597 Archive cluster jobs older than this age, specified in seconds. The default
33598 is 6 hours. This keeps @command{gnt-job list} manageable.
33600 @item @code{verify-disks?} (default: @code{#t})
33601 If this is @code{#f}, the watcher will not try to repair broken DRBD links
33602 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
33605 @item @code{debug?} (default: @code{#f})
33606 When @code{#t}, the script performs additional logging for debugging purposes.
33611 @defvr {Scheme Variable} ganeti-cleaner-service-type
33612 @command{ganeti-cleaner} is a script designed to run periodically and remove
33613 old files from the cluster. This service type controls two @dfn{cron jobs}:
33614 one intended for the master node that permanently purges old cluster jobs,
33615 and one intended for every node that removes expired X509 certificates, keys,
33616 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
33617 it is safe to include even on non-master nodes as it will disable itself as
33620 It takes a @code{ganeti-cleaner-configuration} object.
33623 @deftp {Data Type} ganeti-cleaner-configuration
33626 @item @code{ganeti} (default: @code{ganeti})
33627 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
33629 @item @code{master-schedule} (default: @code{"45 1 * * *"})
33630 How often to run the master cleaning job. The default is once per day, at
33633 @item @code{node-schedule} (default: @code{"45 2 * * *"})
33634 How often to run the node cleaning job. The default is once per day, at
33640 @node Version Control Services
33641 @subsection Version Control Services
33643 The @code{(gnu services version-control)} module provides a service to
33644 allow remote access to local Git repositories. There are three options:
33645 the @code{git-daemon-service}, which provides access to repositories via
33646 the @code{git://} unsecured TCP-based protocol, extending the
33647 @code{nginx} web server to proxy some requests to
33648 @code{git-http-backend}, or providing a web interface with
33649 @code{cgit-service-type}.
33651 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
33653 Return a service that runs @command{git daemon}, a simple TCP server to
33654 expose repositories over the Git protocol for anonymous access.
33656 The optional @var{config} argument should be a
33657 @code{<git-daemon-configuration>} object, by default it allows read-only
33658 access to exported@footnote{By creating the magic file
33659 @file{git-daemon-export-ok} in the repository directory.} repositories under
33664 @deftp {Data Type} git-daemon-configuration
33665 Data type representing the configuration for @code{git-daemon-service}.
33668 @item @code{package} (default: @code{git})
33669 Package object of the Git distributed version control system.
33671 @item @code{export-all?} (default: @code{#f})
33672 Whether to allow access for all Git repositories, even if they do not
33673 have the @file{git-daemon-export-ok} file.
33675 @item @code{base-path} (default: @file{/srv/git})
33676 Whether to remap all the path requests as relative to the given path.
33677 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
33678 @samp{example.com}, then if you later try to pull
33679 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
33680 path as @file{/srv/git/hello.git}.
33682 @item @code{user-path} (default: @code{#f})
33683 Whether to allow @code{~user} notation to be used in requests. When
33684 specified with empty string, requests to
33685 @indicateurl{git://host/~alice/foo} is taken as a request to access
33686 @code{foo} repository in the home directory of user @code{alice}. If
33687 @code{(user-path "@var{path}")} is specified, the same request is taken
33688 as a request to access @file{@var{path}/foo} repository in the home
33689 directory of user @code{alice}.
33691 @item @code{listen} (default: @code{'()})
33692 Whether to listen on specific IP addresses or hostnames, defaults to
33695 @item @code{port} (default: @code{#f})
33696 Whether to listen on an alternative port, which defaults to 9418.
33698 @item @code{whitelist} (default: @code{'()})
33699 If not empty, only allow access to this list of directories.
33701 @item @code{extra-options} (default: @code{'()})
33702 Extra options will be passed to @command{git daemon}, please run
33703 @command{man git-daemon} for more information.
33708 The @code{git://} protocol lacks authentication. When you pull from a
33709 repository fetched via @code{git://}, you don't know whether the data you
33710 receive was modified or is even coming from the specified host, and your
33711 connection is subject to eavesdropping. It's better to use an authenticated
33712 and encrypted transport, such as @code{https}. Although Git allows you
33713 to serve repositories using unsophisticated file-based web servers,
33714 there is a faster protocol implemented by the @code{git-http-backend}
33715 program. This program is the back-end of a proper Git web service. It
33716 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
33717 on running the necessary @code{fcgiwrap} daemon.
33719 Guix has a separate configuration data type for serving Git repositories
33722 @deftp {Data Type} git-http-configuration
33723 Data type representing the configuration for a future
33724 @code{git-http-service-type}; can currently be used to configure Nginx
33725 through @code{git-http-nginx-location-configuration}.
33728 @item @code{package} (default: @var{git})
33729 Package object of the Git distributed version control system.
33731 @item @code{git-root} (default: @file{/srv/git})
33732 Directory containing the Git repositories to expose to the world.
33734 @item @code{export-all?} (default: @code{#f})
33735 Whether to expose access for all Git repositories in @var{git-root},
33736 even if they do not have the @file{git-daemon-export-ok} file.
33738 @item @code{uri-path} (default: @samp{/git/})
33739 Path prefix for Git access. With the default @samp{/git/} prefix, this
33740 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
33741 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
33742 with this prefix are not passed on to this Git instance.
33744 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
33745 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
33750 There is no @code{git-http-service-type}, currently; instead you can
33751 create an @code{nginx-location-configuration} from a
33752 @code{git-http-configuration} and then add that location to a web
33755 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
33756 [config=(git-http-configuration)]
33757 Compute an @code{nginx-location-configuration} that corresponds to the
33758 given Git http configuration. An example nginx service definition to
33759 serve the default @file{/srv/git} over HTTPS might be:
33762 (service nginx-service-type
33763 (nginx-configuration
33766 (nginx-server-configuration
33767 (listen '("443 ssl"))
33768 (server-name "git.my-host.org")
33770 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
33771 (ssl-certificate-key
33772 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
33775 (git-http-nginx-location-configuration
33776 (git-http-configuration (uri-path "/"))))))))))
33779 This example assumes that you are using Let's Encrypt to get your TLS
33780 certificate. @xref{Certificate Services}. The default @code{certbot}
33781 service will redirect all HTTP traffic on @code{git.my-host.org} to
33782 HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
33783 system services. @xref{Web Services}.
33786 @subsubheading Cgit Service
33788 @cindex Cgit service
33789 @cindex Git, web interface
33790 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
33791 repositories written in C.
33793 The following example will configure the service with default values.
33794 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
33797 (service cgit-service-type)
33800 The @code{file-object} type designates either a file-like object
33801 (@pxref{G-Expressions, file-like objects}) or a string.
33803 @c %start of fragment
33805 Available @code{cgit-configuration} fields are:
33807 @deftypevr {@code{cgit-configuration} parameter} package package
33812 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
33813 NGINX configuration.
33817 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
33818 Specifies a command which will be invoked to format the content of about
33819 pages (both top-level and for each repository).
33821 Defaults to @samp{""}.
33825 @deftypevr {@code{cgit-configuration} parameter} string agefile
33826 Specifies a path, relative to each repository path, which can be used to
33827 specify the date and time of the youngest commit in the repository.
33829 Defaults to @samp{""}.
33833 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
33834 Specifies a command that will be invoked for authenticating repository
33837 Defaults to @samp{""}.
33841 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
33842 Flag which, when set to @samp{age}, enables date ordering in the branch
33843 ref list, and when set @samp{name} enables ordering by branch name.
33845 Defaults to @samp{"name"}.
33849 @deftypevr {@code{cgit-configuration} parameter} string cache-root
33850 Path used to store the cgit cache entries.
33852 Defaults to @samp{"/var/cache/cgit"}.
33856 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
33857 Number which specifies the time-to-live, in minutes, for the cached
33858 version of repository pages accessed with a fixed SHA1.
33860 Defaults to @samp{-1}.
33864 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
33865 Number which specifies the time-to-live, in minutes, for the cached
33866 version of repository pages accessed without a fixed SHA1.
33868 Defaults to @samp{5}.
33872 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
33873 Number which specifies the time-to-live, in minutes, for the cached
33874 version of the repository summary page.
33876 Defaults to @samp{5}.
33880 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
33881 Number which specifies the time-to-live, in minutes, for the cached
33882 version of the repository index page.
33884 Defaults to @samp{5}.
33888 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
33889 Number which specifies the time-to-live, in minutes, for the result of
33890 scanning a path for Git repositories.
33892 Defaults to @samp{15}.
33896 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
33897 Number which specifies the time-to-live, in minutes, for the cached
33898 version of the repository about page.
33900 Defaults to @samp{15}.
33904 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
33905 Number which specifies the time-to-live, in minutes, for the cached
33906 version of snapshots.
33908 Defaults to @samp{5}.
33912 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
33913 The maximum number of entries in the cgit cache. When set to @samp{0},
33914 caching is disabled.
33916 Defaults to @samp{0}.
33920 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
33921 Sort items in the repo list case sensitively.
33923 Defaults to @samp{#t}.
33927 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
33928 List of common prefixes which, when combined with a repository URL,
33929 generates valid clone URLs for the repository.
33931 Defaults to @samp{()}.
33935 @deftypevr {@code{cgit-configuration} parameter} list clone-url
33936 List of @code{clone-url} templates.
33938 Defaults to @samp{()}.
33942 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
33943 Command which will be invoked to format commit messages.
33945 Defaults to @samp{""}.
33949 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
33950 Flag which, when set to @samp{date}, enables strict date ordering in the
33951 commit log, and when set to @samp{topo} enables strict topological
33954 Defaults to @samp{"git log"}.
33958 @deftypevr {@code{cgit-configuration} parameter} file-object css
33959 URL which specifies the css document to include in all cgit pages.
33961 Defaults to @samp{"/share/cgit/cgit.css"}.
33965 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
33966 Specifies a command which will be invoked to format names and email
33967 address of committers, authors, and taggers, as represented in various
33968 places throughout the cgit interface.
33970 Defaults to @samp{""}.
33974 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
33975 Flag which, when set to @samp{#t}, will make cgit generate a HTML
33976 fragment suitable for embedding in other HTML pages.
33978 Defaults to @samp{#f}.
33982 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
33983 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
33984 commit history graph to the left of the commit messages in the
33985 repository log page.
33987 Defaults to @samp{#f}.
33991 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
33992 Flag which, when set to @samp{#t}, allows all filter settings to be
33993 overridden in repository-specific cgitrc files.
33995 Defaults to @samp{#f}.
33999 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
34000 Flag which, when set to @samp{#t}, allows users to follow a file in the
34003 Defaults to @samp{#f}.
34007 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
34008 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
34011 Defaults to @samp{#t}.
34015 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
34016 Flag which, when set to @samp{#t}, will make cgit generate extra links
34017 "summary", "commit", "tree" for each repo in the repository index.
34019 Defaults to @samp{#f}.
34023 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
34024 Flag which, when set to @samp{#t}, will make cgit display the owner of
34025 each repo in the repository index.
34027 Defaults to @samp{#t}.
34031 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
34032 Flag which, when set to @samp{#t}, will make cgit print the number of
34033 modified files for each commit on the repository log page.
34035 Defaults to @samp{#f}.
34039 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
34040 Flag which, when set to @samp{#t}, will make cgit print the number of
34041 added and removed lines for each commit on the repository log page.
34043 Defaults to @samp{#f}.
34047 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
34048 Flag which, when set to @code{#t}, will make cgit display remote
34049 branches in the summary and refs views.
34051 Defaults to @samp{#f}.
34055 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
34056 Flag which, when set to @code{1}, will make cgit use the subject of the
34057 parent commit as link text when generating links to parent commits in
34060 Defaults to @samp{#f}.
34064 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
34065 Flag which, when set to @samp{#t}, will make cgit use the subject of the
34066 parent commit as link text when generating links to parent commits in
34069 Defaults to @samp{#f}.
34073 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
34074 Flag which, when set to @samp{#t}, will make cgit generate linenumber
34075 links for plaintext blobs printed in the tree view.
34077 Defaults to @samp{#t}.
34081 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
34082 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
34083 set any repo specific settings.
34085 Defaults to @samp{#f}.
34089 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
34090 URL used as link to a shortcut icon for cgit.
34092 Defaults to @samp{"/favicon.ico"}.
34096 @deftypevr {@code{cgit-configuration} parameter} string footer
34097 The content of the file specified with this option will be included
34098 verbatim at the bottom of all pages (i.e.@: it replaces the standard
34099 "generated by..."@: message).
34101 Defaults to @samp{""}.
34105 @deftypevr {@code{cgit-configuration} parameter} string head-include
34106 The content of the file specified with this option will be included
34107 verbatim in the HTML HEAD section on all pages.
34109 Defaults to @samp{""}.
34113 @deftypevr {@code{cgit-configuration} parameter} string header
34114 The content of the file specified with this option will be included
34115 verbatim at the top of all pages.
34117 Defaults to @samp{""}.
34121 @deftypevr {@code{cgit-configuration} parameter} file-object include
34122 Name of a configfile to include before the rest of the current config-
34125 Defaults to @samp{""}.
34129 @deftypevr {@code{cgit-configuration} parameter} string index-header
34130 The content of the file specified with this option will be included
34131 verbatim above the repository index.
34133 Defaults to @samp{""}.
34137 @deftypevr {@code{cgit-configuration} parameter} string index-info
34138 The content of the file specified with this option will be included
34139 verbatim below the heading on the repository index page.
34141 Defaults to @samp{""}.
34145 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
34146 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
34147 in the servers timezone.
34149 Defaults to @samp{#f}.
34153 @deftypevr {@code{cgit-configuration} parameter} file-object logo
34154 URL which specifies the source of an image which will be used as a logo
34157 Defaults to @samp{"/share/cgit/cgit.png"}.
34161 @deftypevr {@code{cgit-configuration} parameter} string logo-link
34162 URL loaded when clicking on the cgit logo image.
34164 Defaults to @samp{""}.
34168 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
34169 Command which will be invoked to format the Owner column of the main
34172 Defaults to @samp{""}.
34176 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
34177 Number of items to display in atom feeds view.
34179 Defaults to @samp{10}.
34183 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
34184 Number of entries to list per page in "log" view.
34186 Defaults to @samp{50}.
34190 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
34191 Number of commit message characters to display in "log" view.
34193 Defaults to @samp{80}.
34197 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
34198 Specifies the number of entries to list per page on the repository index
34201 Defaults to @samp{50}.
34205 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
34206 Specifies the maximum number of repo description characters to display
34207 on the repository index page.
34209 Defaults to @samp{80}.
34213 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
34214 Specifies the maximum size of a blob to display HTML for in KBytes.
34216 Defaults to @samp{0}.
34220 @deftypevr {@code{cgit-configuration} parameter} string max-stats
34221 Maximum statistics period. Valid values are @samp{week},@samp{month},
34222 @samp{quarter} and @samp{year}.
34224 Defaults to @samp{""}.
34228 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
34229 Mimetype for the specified filename extension.
34231 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
34232 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
34233 "image/png") (svg "image/svg+xml"))}.
34237 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
34238 Specifies the file to use for automatic mimetype lookup.
34240 Defaults to @samp{""}.
34244 @deftypevr {@code{cgit-configuration} parameter} string module-link
34245 Text which will be used as the formatstring for a hyperlink when a
34246 submodule is printed in a directory listing.
34248 Defaults to @samp{""}.
34252 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
34253 If set to the value @samp{#t} caching will be disabled.
34255 Defaults to @samp{#f}.
34259 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
34260 If set to @samp{#t} showing full author email addresses will be
34263 Defaults to @samp{#f}.
34267 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
34268 Flag which, when set to @samp{#t}, will make cgit omit the standard
34269 header on all pages.
34271 Defaults to @samp{#f}.
34275 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
34276 A list of subdirectories inside of @code{repository-directory}, relative
34277 to it, that should loaded as Git repositories. An empty list means that
34278 all subdirectories will be loaded.
34280 Defaults to @samp{()}.
34284 @deftypevr {@code{cgit-configuration} parameter} file-object readme
34285 Text which will be used as default value for @code{cgit-repo-readme}.
34287 Defaults to @samp{""}.
34291 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
34292 If set to @code{#t} and @code{repository-directory} is enabled, if any
34293 repositories are found with a suffix of @code{.git}, this suffix will be
34294 removed for the URL and name.
34296 Defaults to @samp{#f}.
34300 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
34301 Maximum number of files to consider when detecting renames.
34303 Defaults to @samp{-1}.
34307 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
34308 The way in which repositories in each section are sorted.
34310 Defaults to @samp{""}.
34314 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
34315 Text used as content for the @code{robots} meta-tag.
34317 Defaults to @samp{("noindex" "nofollow")}.
34321 @deftypevr {@code{cgit-configuration} parameter} string root-desc
34322 Text printed below the heading on the repository index page.
34324 Defaults to @samp{"a fast webinterface for the git dscm"}.
34328 @deftypevr {@code{cgit-configuration} parameter} string root-readme
34329 The content of the file specified with this option will be included
34330 verbatim below the ``about'' link on the repository index page.
34332 Defaults to @samp{""}.
34336 @deftypevr {@code{cgit-configuration} parameter} string root-title
34337 Text printed as heading on the repository index page.
34339 Defaults to @samp{""}.
34343 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
34344 If set to @samp{#t} and repository-directory is enabled,
34345 repository-directory will recurse into directories whose name starts
34346 with a period. Otherwise, repository-directory will stay away from such
34347 directories, considered as ``hidden''. Note that this does not apply to
34348 the @file{.git} directory in non-bare repos.
34350 Defaults to @samp{#f}.
34354 @deftypevr {@code{cgit-configuration} parameter} list snapshots
34355 Text which specifies the default set of snapshot formats that cgit
34356 generates links for.
34358 Defaults to @samp{()}.
34362 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
34363 Name of the directory to scan for repositories (represents
34366 Defaults to @samp{"/srv/git"}.
34370 @deftypevr {@code{cgit-configuration} parameter} string section
34371 The name of the current repository section - all repositories defined
34372 after this option will inherit the current section name.
34374 Defaults to @samp{""}.
34378 @deftypevr {@code{cgit-configuration} parameter} string section-sort
34379 Flag which, when set to @samp{1}, will sort the sections on the
34380 repository listing by name.
34382 Defaults to @samp{""}.
34386 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
34387 A number which, if defined prior to repository-directory, specifies how
34388 many path elements from each repo path to use as a default section name.
34390 Defaults to @samp{0}.
34394 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
34395 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
34398 Defaults to @samp{#f}.
34402 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
34403 Specifies a command which will be invoked to format plaintext blobs in
34406 Defaults to @samp{""}.
34410 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
34411 Specifies the number of branches to display in the repository ``summary''
34414 Defaults to @samp{10}.
34418 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
34419 Specifies the number of log entries to display in the repository
34422 Defaults to @samp{10}.
34426 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
34427 Specifies the number of tags to display in the repository ``summary''
34430 Defaults to @samp{10}.
34434 @deftypevr {@code{cgit-configuration} parameter} string strict-export
34435 Filename which, if specified, needs to be present within the repository
34436 for cgit to allow access to that repository.
34438 Defaults to @samp{""}.
34442 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
34443 URL which, if specified, will be used as root for all cgit links.
34445 Defaults to @samp{"/"}.
34449 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
34450 A list of @dfn{cgit-repo} records to use with config.
34452 Defaults to @samp{()}.
34454 Available @code{repository-cgit-configuration} fields are:
34456 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
34457 A mask of snapshot formats for this repo that cgit generates links for,
34458 restricted by the global @code{snapshots} setting.
34460 Defaults to @samp{()}.
34464 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
34465 Override the default @code{source-filter}.
34467 Defaults to @samp{""}.
34471 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
34472 The relative URL used to access the repository.
34474 Defaults to @samp{""}.
34478 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
34479 Override the default @code{about-filter}.
34481 Defaults to @samp{""}.
34485 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
34486 Flag which, when set to @samp{age}, enables date ordering in the branch
34487 ref list, and when set to @samp{name} enables ordering by branch name.
34489 Defaults to @samp{""}.
34493 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
34494 A list of URLs which can be used to clone repo.
34496 Defaults to @samp{()}.
34500 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
34501 Override the default @code{commit-filter}.
34503 Defaults to @samp{""}.
34507 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
34508 Flag which, when set to @samp{date}, enables strict date ordering in the
34509 commit log, and when set to @samp{topo} enables strict topological
34512 Defaults to @samp{""}.
34516 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
34517 The name of the default branch for this repository. If no such branch
34518 exists in the repository, the first branch name (when sorted) is used as
34519 default instead. By default branch pointed to by HEAD, or ``master'' if
34520 there is no suitable HEAD.
34522 Defaults to @samp{""}.
34526 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
34527 The value to show as repository description.
34529 Defaults to @samp{""}.
34533 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
34534 The value to show as repository homepage.
34536 Defaults to @samp{""}.
34540 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
34541 Override the default @code{email-filter}.
34543 Defaults to @samp{""}.
34547 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
34548 A flag which can be used to disable the global setting
34549 @code{enable-commit-graph?}.
34551 Defaults to @samp{disabled}.
34555 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
34556 A flag which can be used to disable the global setting
34557 @code{enable-log-filecount?}.
34559 Defaults to @samp{disabled}.
34563 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
34564 A flag which can be used to disable the global setting
34565 @code{enable-log-linecount?}.
34567 Defaults to @samp{disabled}.
34571 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
34572 Flag which, when set to @code{#t}, will make cgit display remote
34573 branches in the summary and refs views.
34575 Defaults to @samp{disabled}.
34579 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
34580 A flag which can be used to override the global setting
34581 @code{enable-subject-links?}.
34583 Defaults to @samp{disabled}.
34587 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
34588 A flag which can be used to override the global setting
34589 @code{enable-html-serving?}.
34591 Defaults to @samp{disabled}.
34595 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
34596 Flag which, when set to @code{#t}, hides the repository from the
34599 Defaults to @samp{#f}.
34603 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
34604 Flag which, when set to @samp{#t}, ignores the repository.
34606 Defaults to @samp{#f}.
34610 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
34611 URL which specifies the source of an image which will be used as a logo
34612 on this repo’s pages.
34614 Defaults to @samp{""}.
34618 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
34619 URL loaded when clicking on the cgit logo image.
34621 Defaults to @samp{""}.
34625 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
34626 Override the default @code{owner-filter}.
34628 Defaults to @samp{""}.
34632 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
34633 Text which will be used as the formatstring for a hyperlink when a
34634 submodule is printed in a directory listing. The arguments for the
34635 formatstring are the path and SHA1 of the submodule commit.
34637 Defaults to @samp{""}.
34641 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
34642 Text which will be used as the formatstring for a hyperlink when a
34643 submodule with the specified subdirectory path is printed in a directory
34646 Defaults to @samp{()}.
34650 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
34651 Override the default maximum statistics period.
34653 Defaults to @samp{""}.
34657 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
34658 The value to show as repository name.
34660 Defaults to @samp{""}.
34664 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
34665 A value used to identify the owner of the repository.
34667 Defaults to @samp{""}.
34671 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
34672 An absolute path to the repository directory.
34674 Defaults to @samp{""}.
34678 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
34679 A path (relative to repo) which specifies a file to include verbatim as
34680 the ``About'' page for this repo.
34682 Defaults to @samp{""}.
34686 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
34687 The name of the current repository section - all repositories defined
34688 after this option will inherit the current section name.
34690 Defaults to @samp{""}.
34694 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
34695 Extra options will be appended to cgitrc file.
34697 Defaults to @samp{()}.
34703 @deftypevr {@code{cgit-configuration} parameter} list extra-options
34704 Extra options will be appended to cgitrc file.
34706 Defaults to @samp{()}.
34711 @c %end of fragment
34713 However, it could be that you just want to get a @code{cgitrc} up and
34714 running. In that case, you can pass an @code{opaque-cgit-configuration}
34715 as a record to @code{cgit-service-type}. As its name indicates, an
34716 opaque configuration does not have easy reflective capabilities.
34718 Available @code{opaque-cgit-configuration} fields are:
34720 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
34724 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
34725 The contents of the @code{cgitrc}, as a string.
34728 For example, if your @code{cgitrc} is just the empty string, you
34729 could instantiate a cgit service like this:
34732 (service cgit-service-type
34733 (opaque-cgit-configuration
34737 @subsubheading Gitolite Service
34739 @cindex Gitolite service
34740 @cindex Git, hosting
34741 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
34742 repositories on a central server.
34744 Gitolite can handle multiple repositories and users, and supports flexible
34745 configuration of the permissions for the users on the repositories.
34747 The following example will configure Gitolite using the default @code{git}
34748 user, and the provided SSH public key.
34751 (service gitolite-service-type
34752 (gitolite-configuration
34753 (admin-pubkey (plain-file
34755 "ssh-rsa AAAA... guix@@example.com"))))
34758 Gitolite is configured through a special admin repository which you can clone,
34759 for example, if you setup Gitolite on @code{example.com}, you would run the
34760 following command to clone the admin repository.
34763 git clone git@@example.com:gitolite-admin
34766 When the Gitolite service is activated, the provided @code{admin-pubkey} will
34767 be inserted in to the @file{keydir} directory in the gitolite-admin
34768 repository. If this results in a change in the repository, it will be
34769 committed using the message ``gitolite setup by GNU Guix''.
34771 @deftp {Data Type} gitolite-configuration
34772 Data type representing the configuration for @code{gitolite-service-type}.
34775 @item @code{package} (default: @var{gitolite})
34776 Gitolite package to use.
34778 @item @code{user} (default: @var{git})
34779 User to use for Gitolite. This will be user that you use when accessing
34782 @item @code{group} (default: @var{git})
34783 Group to use for Gitolite.
34785 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
34786 Directory in which to store the Gitolite configuration and repositories.
34788 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
34789 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
34790 representing the configuration for Gitolite.
34792 @item @code{admin-pubkey} (default: @var{#f})
34793 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
34794 setup Gitolite. This will be inserted in to the @file{keydir} directory
34795 within the gitolite-admin repository.
34797 To specify the SSH key as a string, use the @code{plain-file} function.
34800 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
34806 @deftp {Data Type} gitolite-rc-file
34807 Data type representing the Gitolite RC file.
34810 @item @code{umask} (default: @code{#o0077})
34811 This controls the permissions Gitolite sets on the repositories and their
34814 A value like @code{#o0027} will give read access to the group used by Gitolite
34815 (by default: @code{git}). This is necessary when using Gitolite with software
34816 like cgit or gitweb.
34818 @item @code{unsafe-pattern} (default: @code{#f})
34819 An optional Perl regular expression for catching unsafe configurations in
34820 the configuration file. See
34821 @uref{https://gitolite.com/gitolite/git-config.html#compensating-for-unsafe_patt,
34822 Gitolite's documentation} for more information.
34824 When the value is not @code{#f}, it should be a string containing a Perl
34825 regular expression, such as @samp{"[`~#\$\&()|;<>]"}, which is the default
34826 value used by gitolite. It rejects any special character in configuration
34827 that might be interpreted by a shell, which is useful when sharing the
34828 administration burden with other people that do not otherwise have shell
34829 access on the server.
34831 @item @code{git-config-keys} (default: @code{""})
34832 Gitolite allows you to set git config values using the @samp{config}
34833 keyword. This setting allows control over the config keys to accept.
34835 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
34836 Set the role names allowed to be used by users running the perms command.
34838 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
34839 This setting controls the commands and features to enable within Gitolite.
34845 @subsubheading Gitile Service
34847 @cindex Gitile service
34849 @uref{https://git.lepiller.eu/gitile, Gitile} is a Git forge for viewing
34850 public git repository contents from a web browser.
34852 Gitile works best in collaboration with Gitolite, and will serve the public
34853 repositories from Gitolite by default. The service should listen only on
34854 a local port, and a webserver should be configured to serve static resources.
34855 The gitile service provides an easy way to extend the Nginx service for
34856 that purpose (@pxref{NGINX}).
34858 The following example will configure Gitile to serve repositories from a
34859 custom location, with some default messages for the home page and the
34863 (service gitile-service-type
34864 (gitile-configuration
34865 (repositories "/srv/git")
34866 (base-git-url "https://myweb.site/git")
34867 (index-title "My git repositories")
34868 (intro '((p "This is all my public work!")))
34869 (footer '((p "This is the end")))
34870 (nginx-server-block
34871 (nginx-server-configuration
34873 "/etc/letsencrypt/live/myweb.site/fullchain.pem")
34874 (ssl-certificate-key
34875 "/etc/letsencrypt/live/myweb.site/privkey.pem")
34876 (listen '("443 ssl http2" "[::]:443 ssl http2"))
34879 ;; Allow for https anonymous fetch on /git/ urls.
34880 (git-http-nginx-location-configuration
34881 (git-http-configuration
34883 (git-root "/var/lib/gitolite/repositories")))))))))
34886 In addition to the configuration record, you should configure your git
34887 repositories to contain some optional information. First, your public
34888 repositories need to contain the @file{git-daemon-export-ok} magic file
34889 that allows Git to export the repository. Gitile uses the presence of this
34890 file to detect public repositories it should make accessible. To do so with
34891 Gitolite for instance, modify your @file{conf/gitolite.conf} to include
34892 this in the repositories you want to make public:
34899 In addition, Gitile can read the repository configuration to display more
34900 information on the repository. Gitile uses the gitweb namespace for its
34901 configuration. As an example, you can use the following in your
34902 @file{conf/gitolite.conf}:
34907 desc = A long description, optionally with <i>HTML</i>, shown on the index page
34908 config gitweb.name = The Foo Project
34909 config gitweb.synopsis = A short description, shown on the main page of the project
34912 Do not forget to commit and push these changes once you are satisfied. You
34913 may need to change your gitolite configuration to allow the previous
34914 configuration options to be set. One way to do that is to add the
34915 following service definition:
34918 (service gitolite-service-type
34919 (gitolite-configuration
34920 (admin-pubkey (local-file "key.pub"))
34924 ;; Allow to set any configuration key
34925 (git-config-keys ".*")
34926 ;; Allow any text as a valid configuration value
34927 (unsafe-patt "^$")))))
34930 @deftp {Data Type} gitile-configuration
34931 Data type representing the configuration for @code{gitile-service-type}.
34934 @item @code{package} (default: @var{gitile})
34935 Gitile package to use.
34937 @item @code{host} (default: @code{"localhost"})
34938 The host on which gitile is listening.
34940 @item @code{port} (default: @code{8080})
34941 The port on which gitile is listening.
34943 @item @code{database} (default: @code{"/var/lib/gitile/gitile-db.sql"})
34944 The location of the database.
34946 @item @code{repositories} (default: @code{"/var/lib/gitolite/repositories"})
34947 The location of the repositories. Note that only public repositories will
34948 be shown by Gitile. To make a repository public, add an empty
34949 @file{git-daemon-export-ok} file at the root of that repository.
34951 @item @code{base-git-url}
34952 The base git url that will be used to show clone commands.
34954 @item @code{index-title} (default: @code{"Index"})
34955 The page title for the index page that lists all the available repositories.
34957 @item @code{intro} (default: @code{'()})
34958 The intro content, as a list of sxml expressions. This is shown above the list
34959 of repositories, on the index page.
34961 @item @code{footer} (default: @code{'()})
34962 The footer content, as a list of sxml expressions. This is shown on every
34963 page served by Gitile.
34965 @item @code{nginx-server-block}
34966 An nginx server block that will be extended and used as a reverse proxy by
34967 Gitile to serve its pages, and as a normal web server to serve its assets.
34969 You can use this block to add more custom URLs to your domain, such as a
34970 @code{/git/} URL for anonymous clones, or serving any other files you would
34976 @node Game Services
34977 @subsection Game Services
34979 @subsubheading The Battle for Wesnoth Service
34981 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
34982 based tactical strategy game, with several single player campaigns, and
34983 multiplayer games (both networked and local).
34985 @defvar {Scheme Variable} wesnothd-service-type
34986 Service type for the wesnothd service. Its value must be a
34987 @code{wesnothd-configuration} object. To run wesnothd in the default
34988 configuration, instantiate it as:
34991 (service wesnothd-service-type)
34995 @deftp {Data Type} wesnothd-configuration
34996 Data type representing the configuration of @command{wesnothd}.
34999 @item @code{package} (default: @code{wesnoth-server})
35000 The wesnoth server package to use.
35002 @item @code{port} (default: @code{15000})
35003 The port to bind the server to.
35008 @node PAM Mount Service
35009 @subsection PAM Mount Service
35012 The @code{(gnu services pam-mount)} module provides a service allowing
35013 users to mount volumes when they log in. It should be able to mount any
35014 volume format supported by the system.
35016 @defvar {Scheme Variable} pam-mount-service-type
35017 Service type for PAM Mount support.
35020 @deftp {Data Type} pam-mount-configuration
35021 Data type representing the configuration of PAM Mount.
35023 It takes the following parameters:
35027 The configuration rules that will be used to generate
35028 @file{/etc/security/pam_mount.conf.xml}.
35030 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
35031 Guile Reference Manual}), and the default ones don't mount anything for
35035 `((debug (@@ (enable "0")))
35036 (mntoptions (@@ (allow ,(string-join
35037 '("nosuid" "nodev" "loop"
35038 "encryption" "fsck" "nonempty"
35039 "allow_root" "allow_other")
35041 (mntoptions (@@ (require "nosuid,nodev")))
35042 (logout (@@ (wait "0")
35046 (mkmountpoint (@@ (enable "1")
35050 Some @code{volume} elements must be added to automatically mount volumes
35051 at login. Here's an example allowing the user @code{alice} to mount her
35052 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
35053 the partition where he stores his data:
35056 (define pam-mount-rules
35057 `((debug (@@ (enable "0")))
35058 (volume (@@ (user "alice")
35061 (mountpoint "/home/alice")))
35062 (volume (@@ (user "bob")
35065 (mountpoint "/home/bob/data")
35066 (options "defaults,autodefrag,compress")))
35067 (mntoptions (@@ (allow ,(string-join
35068 '("nosuid" "nodev" "loop"
35069 "encryption" "fsck" "nonempty"
35070 "allow_root" "allow_other")
35072 (mntoptions (@@ (require "nosuid,nodev")))
35073 (logout (@@ (wait "0")
35077 (mkmountpoint (@@ (enable "1")
35078 (remove "true")))))
35080 (service pam-mount-service-type
35081 (pam-mount-configuration
35082 (rules pam-mount-rules)))
35085 The complete list of possible options can be found in the man page for
35086 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
35091 @node Guix Services
35092 @subsection Guix Services
35094 @subsubheading Guix Build Coordinator
35095 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
35096 Coordinator} aids in distributing derivation builds among machines
35097 running an @dfn{agent}. The build daemon is still used to build the
35098 derivations, but the Guix Build Coordinator manages allocating builds
35099 and working with the results.
35101 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
35102 more connected @dfn{agent} processes. The coordinator process handles
35103 clients submitting builds, and allocating builds to agents. The agent
35104 processes talk to a build daemon to actually perform the builds, then
35105 send the results back to the coordinator.
35107 There is a script to run the coordinator component of the Guix Build
35108 Coordinator, but the Guix service uses a custom Guile script instead, to
35109 provide better integration with G-expressions used in the configuration.
35111 @defvar {Scheme Variable} guix-build-coordinator-service-type
35112 Service type for the Guix Build Coordinator. Its value must be a
35113 @code{guix-build-coordinator-configuration} object.
35116 @deftp {Data Type} guix-build-coordinator-configuration
35117 Data type representing the configuration of the Guix Build Coordinator.
35120 @item @code{package} (default: @code{guix-build-coordinator})
35121 The Guix Build Coordinator package to use.
35123 @item @code{user} (default: @code{"guix-build-coordinator"})
35124 The system user to run the service as.
35126 @item @code{group} (default: @code{"guix-build-coordinator"})
35127 The system group to run the service as.
35129 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
35130 The URI to use for the database.
35132 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
35133 The URI describing how to listen to requests from agent processes.
35135 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
35136 The URI describing how to listen to requests from clients. The client
35137 API allows submitting builds and currently isn't authenticated, so take
35138 care when configuring this value.
35140 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
35141 A G-expression for the allocation strategy to be used. This is a
35142 procedure that takes the datastore as an argument and populates the
35143 allocation plan in the database.
35145 @item @code{hooks} (default: @var{'()})
35146 An association list of hooks. These provide a way to execute arbitrary
35147 code upon certain events, like a build result being processed.
35149 @item @code{parallel-hooks} (default: @var{'()})
35150 Hooks can be configured to run in parallel. This parameter is an
35151 association list of hooks to do in parallel, where the key is the symbol
35152 for the hook and the value is the number of threads to run.
35154 @item @code{guile} (default: @code{guile-3.0-latest})
35155 The Guile package with which to run the Guix Build Coordinator.
35160 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
35161 Service type for a Guix Build Coordinator agent. Its value must be a
35162 @code{guix-build-coordinator-agent-configuration} object.
35165 @deftp {Data Type} guix-build-coordinator-agent-configuration
35166 Data type representing the configuration a Guix Build Coordinator agent.
35169 @item @code{package} (default: @code{guix-build-coordinator/agent-only})
35170 The Guix Build Coordinator package to use.
35172 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
35173 The system user to run the service as.
35175 @item @code{coordinator} (default: @code{"http://localhost:8745"})
35176 The URI to use when connecting to the coordinator.
35178 @item @code{authentication}
35179 Record describing how this agent should authenticate with the
35180 coordinator. Possible record types are described below.
35182 @item @code{systems} (default: @code{#f})
35183 The systems for which this agent should fetch builds. The agent process
35184 will use the current system it's running on as the default.
35186 @item @code{max-parallel-builds} (default: @code{1})
35187 The number of builds to perform in parallel.
35189 @item @code{max-1min-load-average} (default: @code{#f})
35190 Load average value to look at when considering starting new builds, if
35191 the 1 minute load average exceeds this value, the agent will wait before
35192 starting new builds.
35194 This will be unspecified if the value is @code{#f}, and the agent will
35195 use the number of cores reported by the system as the max 1 minute load
35198 @item @code{derivation-substitute-urls} (default: @code{#f})
35199 URLs from which to attempt to fetch substitutes for derivations, if the
35200 derivations aren't already available.
35202 @item @code{non-derivation-substitute-urls} (default: @code{#f})
35203 URLs from which to attempt to fetch substitutes for build inputs, if the
35204 input store items aren't already available.
35209 @deftp {Data Type} guix-build-coordinator-agent-password-auth
35210 Data type representing an agent authenticating with a coordinator via a
35215 The UUID of the agent. This should be generated by the coordinator
35216 process, stored in the coordinator database, and used by the intended
35219 @item @code{password}
35220 The password to use when connecting to the coordinator.
35225 @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
35226 Data type representing an agent authenticating with a coordinator via a
35227 UUID and password read from a file.
35231 The UUID of the agent. This should be generated by the coordinator
35232 process, stored in the coordinator database, and used by the intended
35235 @item @code{password-file}
35236 A file containing the password to use when connecting to the
35242 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
35243 Data type representing an agent authenticating with a coordinator via a
35244 dynamic auth token and agent name.
35247 @item @code{agent-name}
35248 Name of an agent, this is used to match up to an existing entry in the
35249 database if there is one. When no existing entry is found, a new entry
35250 is automatically added.
35253 Dynamic auth token, this is created and stored in the coordinator
35254 database, and is used by the agent to authenticate.
35259 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
35260 Data type representing an agent authenticating with a coordinator via a
35261 dynamic auth token read from a file and agent name.
35264 @item @code{agent-name}
35265 Name of an agent, this is used to match up to an existing entry in the
35266 database if there is one. When no existing entry is found, a new entry
35267 is automatically added.
35269 @item @code{token-file}
35270 File containing the dynamic auth token, this is created and stored in
35271 the coordinator database, and is used by the agent to authenticate.
35276 The Guix Build Coordinator package contains a script to query an
35277 instance of the Guix Data Service for derivations to build, and then
35278 submit builds for those derivations to the coordinator. The service
35279 type below assists in running this script. This is an additional tool
35280 that may be useful when building derivations contained within an
35281 instance of the Guix Data Service.
35283 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
35284 Service type for the
35285 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
35286 value must be a @code{guix-build-coordinator-queue-builds-configuration}
35290 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
35291 Data type representing the options to the queue builds from guix data
35295 @item @code{package} (default: @code{guix-build-coordinator})
35296 The Guix Build Coordinator package to use.
35298 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
35299 The system user to run the service as.
35301 @item @code{coordinator} (default: @code{"http://localhost:8746"})
35302 The URI to use when connecting to the coordinator.
35304 @item @code{systems} (default: @code{#f})
35305 The systems for which to fetch derivations to build.
35307 @item @code{systems-and-targets} (default: @code{#f})
35308 An association list of system and target pairs for which to fetch
35309 derivations to build.
35311 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
35312 The Guix Data Service instance from which to query to find out about
35313 derivations to build.
35315 @item @code{guix-data-service-build-server-id} (default: @code{#f})
35316 The Guix Data Service build server ID corresponding to the builds being
35317 submitted. Providing this speeds up the submitting of builds as
35318 derivations that have already been submitted can be skipped before
35319 asking the coordinator to build them.
35321 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
35322 A file to record which commits have been processed, to avoid needlessly
35323 processing them again if the service is restarted.
35328 @subsubheading Guix Data Service
35329 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
35330 and provides data about GNU Guix. This includes information about
35331 packages, derivations and lint warnings.
35333 The data is stored in a PostgreSQL database, and available through a web
35336 @defvar {Scheme Variable} guix-data-service-type
35337 Service type for the Guix Data Service. Its value must be a
35338 @code{guix-data-service-configuration} object. The service optionally
35339 extends the getmail service, as the guix-commits mailing list is used to
35340 find out about changes in the Guix git repository.
35343 @deftp {Data Type} guix-data-service-configuration
35344 Data type representing the configuration of the Guix Data Service.
35347 @item @code{package} (default: @code{guix-data-service})
35348 The Guix Data Service package to use.
35350 @item @code{user} (default: @code{"guix-data-service"})
35351 The system user to run the service as.
35353 @item @code{group} (default: @code{"guix-data-service"})
35354 The system group to run the service as.
35356 @item @code{port} (default: @code{8765})
35357 The port to bind the web service to.
35359 @item @code{host} (default: @code{"127.0.0.1"})
35360 The host to bind the web service to.
35362 @item @code{getmail-idle-mailboxes} (default: @code{#f})
35363 If set, this is the list of mailboxes that the getmail service will be
35364 configured to listen to.
35366 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
35367 If set, this is the @code{getmail-retriever-configuration} object with
35368 which to configure getmail to fetch mail from the guix-commits mailing
35371 @item @code{extra-options} (default: @var{'()})
35372 Extra command line options for @code{guix-data-service}.
35374 @item @code{extra-process-jobs-options} (default: @var{'()})
35375 Extra command line options for @code{guix-data-service-process-jobs}.
35380 @subsubheading Nar Herder
35381 The @uref{https://git.cbaines.net/guix/nar-herder/about/,Nar Herder} is
35382 a utility for managing a collection of nars.
35384 @defvar {Scheme Variable} nar-herder-type
35385 Service type for the Guix Data Service. Its value must be a
35386 @code{nar-herder-configuration} object. The service optionally
35387 extends the getmail service, as the guix-commits mailing list is used to
35388 find out about changes in the Guix git repository.
35391 @deftp {Data Type} nar-herder-configuration
35392 Data type representing the configuration of the Guix Data Service.
35395 @item @code{package} (default: @code{nar-herder})
35396 The Nar Herder package to use.
35398 @item @code{user} (default: @code{"nar-herder"})
35399 The system user to run the service as.
35401 @item @code{group} (default: @code{"nar-herder"})
35402 The system group to run the service as.
35404 @item @code{port} (default: @code{8734})
35405 The port to bind the server to.
35407 @item @code{host} (default: @code{"127.0.0.1"})
35408 The host to bind the server to.
35410 @item @code{mirror} (default: @code{#f})
35411 Optional URL of the other Nar Herder instance which should be mirrored.
35412 This means that this Nar Herder instance will download it's database,
35413 and keep it up to date.
35415 @item @code{database} (default: @code{"/var/lib/nar-herder/nar_herder.db"})
35416 Location for the database. If this Nar Herder instance is mirroring
35417 another, the database will be downloaded if it doesn't exist. If this
35418 Nar Herder instance isn't mirroring another, an empty database will be
35421 @item @code{database-dump} (default: @code{"/var/lib/nar-herder/nar_herder_dump.db"})
35422 Location of the database dump. This is created and regularly updated by
35423 taking a copy of the database. This is the version of the database that
35424 is available to download.
35426 @item @code{storage} (default: @code{#f})
35427 Optional location in which to store nars.
35429 @item @code{storage-limit} (default: @code{"none"})
35430 Limit in bytes for the nars stored in the storage location. This can
35431 also be set to ``none'' so that there is no limit.
35433 When the storage location exceeds this size, nars are removed according
35434 to the nar removal criteria.
35436 @item @code{storage-nar-removal-criteria} (default: @code{'()})
35437 Criteria used to remove nars from the storage location. These are used
35438 in conjunction with the storage limit.
35440 When the storage location exceeds the storage limit size, nars will be
35441 checked against the nar removal criteria and if any of the criteria
35442 match, they will be removed. This will continue until the storage
35443 location is below the storage limit size.
35445 Each criteria is specified by a string, then an equals sign, then
35446 another string. Currently, only one criteria is supported, checking if a
35447 nar is stored on another Nar Herder instance.
35449 @item @code{ttl} (default: @code{#f})
35450 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
35451 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
35452 days, @code{1m} means 1 month, and so on.
35454 This allows the user's Guix to keep substitute information in cache for
35457 @item @code{negative-ttl} (default: @code{#f})
35458 Similarly produce @code{Cache-Control} HTTP headers to advertise the
35459 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
35460 which the HTTP 404 code is returned. By default, no negative TTL is
35463 @item @code{log-level} (default: @code{'DEBUG})
35464 Log level to use, specify a log level like @code{'INFO} to stop logging
35465 individual requests.
35470 @node Linux Services
35471 @subsection Linux Services
35474 @cindex out of memory killer
35476 @cindex early out of memory daemon
35477 @subsubheading Early OOM Service
35479 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
35480 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
35481 space and provides a more responsive and configurable alternative to the
35482 in-kernel OOM killer. It is useful to prevent the system from becoming
35483 unresponsive when it runs out of memory.
35485 @deffn {Scheme Variable} earlyoom-service-type
35486 The service type for running @command{earlyoom}, the Early OOM daemon.
35487 Its value must be a @code{earlyoom-configuration} object, described
35488 below. The service can be instantiated in its default configuration
35492 (service earlyoom-service-type)
35496 @deftp {Data Type} earlyoom-configuration
35497 This is the configuration record for the @code{earlyoom-service-type}.
35500 @item @code{earlyoom} (default: @var{earlyoom})
35501 The Earlyoom package to use.
35503 @item @code{minimum-available-memory} (default: @code{10})
35504 The threshold for the minimum @emph{available} memory, in percentages.
35506 @item @code{minimum-free-swap} (default: @code{10})
35507 The threshold for the minimum free swap memory, in percentages.
35509 @item @code{prefer-regexp} (default: @code{#f})
35510 A regular expression (as a string) to match the names of the processes
35511 that should be preferably killed.
35513 @item @code{avoid-regexp} (default: @code{#f})
35514 A regular expression (as a string) to match the names of the processes
35515 that should @emph{not} be killed.
35517 @item @code{memory-report-interval} (default: @code{0})
35518 The interval in seconds at which a memory report is printed. It is
35519 disabled by default.
35521 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
35522 A boolean indicating whether the positive adjustments set in
35523 @file{/proc/*/oom_score_adj} should be ignored.
35525 @item @code{show-debug-messages?} (default: @code{#f})
35526 A boolean indicating whether debug messages should be printed. The logs
35527 are saved at @file{/var/log/earlyoom.log}.
35529 @item @code{send-notification-command} (default: @code{#f})
35530 This can be used to provide a custom command used for sending
35536 @cindex kernel module loader
35537 @subsubheading Kernel Module Loader Service
35539 The kernel module loader service allows one to load loadable kernel
35540 modules at boot. This is especially useful for modules that don't
35541 autoload and need to be manually loaded, as is the case with
35544 @deffn {Scheme Variable} kernel-module-loader-service-type
35545 The service type for loading loadable kernel modules at boot with
35546 @command{modprobe}. Its value must be a list of strings representing
35547 module names. For example loading the drivers provided by
35548 @code{ddcci-driver-linux}, in debugging mode by passing some module
35549 parameters, can be done as follow:
35552 (use-modules (gnu) (gnu services))
35553 (use-package-modules linux)
35554 (use-service-modules linux)
35556 (define ddcci-config
35557 (plain-file "ddcci.conf"
35558 "options ddcci dyndbg delay=120"))
35562 (services (cons* (service kernel-module-loader-service-type
35563 '("ddcci" "ddcci_backlight"))
35564 (simple-service 'ddcci-config etc-service-type
35565 (list `("modprobe.d/ddcci.conf"
35568 (kernel-loadable-modules (list ddcci-driver-linux)))
35573 @cindex Platform Reliability, Availability and Serviceability daemon
35574 @subsubheading Rasdaemon Service
35576 The Rasdaemon service provides a daemon which monitors platform
35577 @acronym{RAS, Reliability@comma{} Availability@comma{} and Serviceability} reports from
35578 Linux kernel trace events, logging them to syslogd.
35580 Reliability, Availability and Serviceability is a concept used on servers meant
35581 to measure their robustness.
35583 @strong{Relability} is the probability that a system will produce correct
35587 @item Generally measured as Mean Time Between Failures (MTBF), and
35588 @item Enhanced by features that help to avoid, detect and repair hardware
35592 @strong{Availability} is the probability that a system is operational at a
35596 @item Generally measured as a percentage of downtime per a period of time, and
35597 @item Often uses mechanisms to detect and correct hardware faults in runtime.
35600 @strong{Serviceability} is the simplicity and speed with which a system can be
35601 repaired or maintained:
35604 @item Generally measured on Mean Time Between Repair (MTBR).
35608 Among the monitoring measures, the most usual ones include:
35611 @item CPU – detect errors at instruction execution and at L1/L2/L3 caches;
35612 @item Memory – add error correction logic (ECC) to detect and correct errors;
35613 @item I/O – add CRC checksums for transferred data;
35614 @item Storage – RAID, journal file systems, checksums, Self-Monitoring,
35615 Analysis and Reporting Technology (SMART).
35618 By monitoring the number of occurrences of error detections, it is possible to
35619 identify if the probability of hardware errors is increasing, and, on such
35620 case, do a preventive maintenance to replace a degraded component while those
35621 errors are correctable.
35623 For detailed information about the types of error events gathered and how to
35624 make sense of them, see the kernel administrator's guide at
35625 @url{https://www.kernel.org/doc/html/latest/admin-guide/ras.html}.
35627 @defvr {Scheme Variable} rasdaemon-service-type
35628 Service type for the @command{rasdaemon} service. It accepts a
35629 @code{rasdaemon-configuration} object. Instantiating like
35632 (service rasdaemon-service-type)
35635 will load with a default configuration, which monitors all events and logs to
35639 @deftp {Data Type} rasdaemon-configuration
35640 The data type representing the configuration of @command{rasdaemon}.
35643 @item @code{record?} (default: @code{#f})
35645 A boolean indicating whether to record the events in an SQLite database. This
35646 provides a more structured access to the information contained in the log file.
35647 The database location is hard-coded to @file{/var/lib/rasdaemon/ras-mc_event.db}.
35653 @cindex compressed swap
35654 @cindex Compressed RAM-based block devices
35655 @subsubheading Zram Device Service
35657 The Zram device service provides a compressed swap device in system
35658 memory. The Linux Kernel documentation has more information about
35659 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
35662 @deffn {Scheme Variable} zram-device-service-type
35663 This service creates the zram block device, formats it as swap and
35664 enables it as a swap device. The service's value is a
35665 @code{zram-device-configuration} record.
35667 @deftp {Data Type} zram-device-configuration
35668 This is the data type representing the configuration for the zram-device
35672 @item @code{size} (default @code{"1G"})
35673 This is the amount of space you wish to provide for the zram device. It
35674 accepts a string and can be a number of bytes or use a suffix, eg.:
35675 @code{"512M"} or @code{1024000}.
35676 @item @code{compression-algorithm} (default @code{'lzo})
35677 This is the compression algorithm you wish to use. It is difficult to
35678 list all the possible compression options, but common ones supported by
35679 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
35680 @item @code{memory-limit} (default @code{0})
35681 This is the maximum amount of memory which the zram device can use.
35682 Setting it to '0' disables the limit. While it is generally expected
35683 that compression will be 2:1, it is possible that uncompressable data
35684 can be written to swap and this is a method to limit how much memory can
35685 be used. It accepts a string and can be a number of bytes or use a
35686 suffix, eg.: @code{"2G"}.
35687 @item @code{priority} (default @code{#f})
35688 This is the priority of the swap device created from the zram device.
35689 @xref{Swap Space} for a description of swap priorities. You might want
35690 to set a specific priority for the zram device, otherwise it could end
35691 up not being used much for the reasons described there.
35697 @node Hurd Services
35698 @subsection Hurd Services
35700 @defvr {Scheme Variable} hurd-console-service-type
35701 This service starts the fancy @code{VGA} console client on the Hurd.
35703 The service's value is a @code{hurd-console-configuration} record.
35706 @deftp {Data Type} hurd-console-configuration
35707 This is the data type representing the configuration for the
35708 hurd-console-service.
35711 @item @code{hurd} (default: @var{hurd})
35712 The Hurd package to use.
35716 @defvr {Scheme Variable} hurd-getty-service-type
35717 This service starts a tty using the Hurd @code{getty} program.
35719 The service's value is a @code{hurd-getty-configuration} record.
35722 @deftp {Data Type} hurd-getty-configuration
35723 This is the data type representing the configuration for the
35724 hurd-getty-service.
35727 @item @code{hurd} (default: @var{hurd})
35728 The Hurd package to use.
35731 The name of the console this Getty runs on---e.g., @code{"tty1"}.
35733 @item @code{baud-rate} (default: @code{38400})
35734 An integer specifying the baud rate of the tty.
35739 @node Miscellaneous Services
35740 @subsection Miscellaneous Services
35742 @cindex fingerprint
35743 @subsubheading Fingerprint Service
35745 The @code{(gnu services authentication)} module provides a DBus service to
35746 read and identify fingerprints via a fingerprint sensor.
35748 @defvr {Scheme Variable} fprintd-service-type
35749 The service type for @command{fprintd}, which provides the fingerprint
35750 reading capability.
35753 (service fprintd-service-type)
35758 @subsubheading System Control Service
35760 The @code{(gnu services sysctl)} provides a service to configure kernel
35761 parameters at boot.
35763 @defvr {Scheme Variable} sysctl-service-type
35764 The service type for @command{sysctl}, which modifies kernel parameters
35765 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
35769 (service sysctl-service-type
35770 (sysctl-configuration
35771 (settings '(("net.ipv4.ip_forward" . "1")))))
35774 Since @code{sysctl-service-type} is used in the default lists of
35775 services, @code{%base-services} and @code{%desktop-services}, you can
35776 use @code{modify-services} to change its configuration and add the
35777 kernel parameters that you want (@pxref{Service Reference,
35778 @code{modify-services}}).
35781 (modify-services %base-services
35782 (sysctl-service-type config =>
35783 (sysctl-configuration
35784 (settings (append '(("net.ipv4.ip_forward" . "1"))
35785 %default-sysctl-settings)))))
35790 @deftp {Data Type} sysctl-configuration
35791 The data type representing the configuration of @command{sysctl}.
35794 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
35795 The @command{sysctl} executable to use.
35797 @item @code{settings} (default: @code{%default-sysctl-settings})
35798 An association list specifies kernel parameters and their values.
35802 @defvr {Scheme Variable} %default-sysctl-settings
35803 An association list specifying the default @command{sysctl} parameters
35808 @subsubheading PC/SC Smart Card Daemon Service
35810 The @code{(gnu services security-token)} module provides the following service
35811 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
35812 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
35813 manager that coordinates communications with smart card readers, smart cards
35814 and cryptographic tokens that are connected to the system.
35816 @defvr {Scheme Variable} pcscd-service-type
35817 Service type for the @command{pcscd} service. Its value must be a
35818 @code{pcscd-configuration} object. To run pcscd in the default
35819 configuration, instantiate it as:
35822 (service pcscd-service-type)
35826 @deftp {Data Type} pcscd-configuration
35827 The data type representing the configuration of @command{pcscd}.
35830 @item @code{pcsc-lite} (default: @code{pcsc-lite})
35831 The pcsc-lite package that provides pcscd.
35832 @item @code{usb-drivers} (default: @code{(list ccid)})
35833 List of packages that provide USB drivers to pcscd. Drivers are expected to be
35834 under @file{pcsc/drivers} in the store directory of the package.
35839 @subsubheading Lirc Service
35841 The @code{(gnu services lirc)} module provides the following service.
35843 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
35844 [#:device #f] [#:driver #f] [#:config-file #f] @
35845 [#:extra-options '()]
35846 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
35847 decodes infrared signals from remote controls.
35849 Optionally, @var{device}, @var{driver} and @var{config-file}
35850 (configuration file name) may be specified. See @command{lircd} manual
35853 Finally, @var{extra-options} is a list of additional command-line options
35854 passed to @command{lircd}.
35858 @subsubheading Spice Service
35860 The @code{(gnu services spice)} module provides the following service.
35862 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
35863 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
35864 that enables sharing the clipboard with a vm and setting the guest display
35865 resolution when the graphical console window resizes.
35868 @cindex inputattach
35869 @subsubheading inputattach Service
35871 @cindex tablet input, for Xorg
35872 @cindex touchscreen input, for Xorg
35873 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
35874 use input devices such as Wacom tablets, touchscreens, or joysticks with the
35875 Xorg display server.
35877 @deffn {Scheme Variable} inputattach-service-type
35878 Type of a service that runs @command{inputattach} on a device and
35879 dispatches events from it.
35882 @deftp {Data Type} inputattach-configuration
35884 @item @code{device-type} (default: @code{"wacom"})
35885 The type of device to connect to. Run @command{inputattach --help}, from the
35886 @code{inputattach} package, to see the list of supported device types.
35888 @item @code{device} (default: @code{"/dev/ttyS0"})
35889 The device file to connect to the device.
35891 @item @code{baud-rate} (default: @code{#f})
35892 Baud rate to use for the serial connection.
35893 Should be a number or @code{#f}.
35895 @item @code{log-file} (default: @code{#f})
35896 If true, this must be the name of a file to log messages to.
35900 @subsubheading Dictionary Service
35902 The @code{(gnu services dict)} module provides the following service:
35904 @defvr {Scheme Variable} dicod-service-type
35905 This is the type of the service that runs the @command{dicod} daemon, an
35906 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
35909 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
35910 Return a service that runs the @command{dicod} daemon, an implementation
35911 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
35913 The optional @var{config} argument specifies the configuration for
35914 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
35915 default it serves the GNU Collaborative International Dictionary of English.
35917 You can add @command{open localhost} to your @file{~/.dico} file to make
35918 @code{localhost} the default server for @command{dico} client
35919 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
35922 @deftp {Data Type} dicod-configuration
35923 Data type representing the configuration of dicod.
35926 @item @code{dico} (default: @var{dico})
35927 Package object of the GNU Dico dictionary server.
35929 @item @code{interfaces} (default: @var{'("localhost")})
35930 This is the list of IP addresses and ports and possibly socket file
35931 names to listen to (@pxref{Server Settings, @code{listen} directive,,
35932 dico, GNU Dico Manual}).
35934 @item @code{handlers} (default: @var{'()})
35935 List of @code{<dicod-handler>} objects denoting handlers (module instances).
35937 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
35938 List of @code{<dicod-database>} objects denoting dictionaries to be served.
35942 @deftp {Data Type} dicod-handler
35943 Data type representing a dictionary handler (module instance).
35947 Name of the handler (module instance).
35949 @item @code{module} (default: @var{#f})
35950 Name of the dicod module of the handler (instance). If it is @code{#f},
35951 the module has the same name as the handler.
35952 (@pxref{Modules,,, dico, GNU Dico Manual}).
35954 @item @code{options}
35955 List of strings or gexps representing the arguments for the module handler
35959 @deftp {Data Type} dicod-database
35960 Data type representing a dictionary database.
35964 Name of the database, will be used in DICT commands.
35966 @item @code{handler}
35967 Name of the dicod handler (module instance) used by this database
35968 (@pxref{Handlers,,, dico, GNU Dico Manual}).
35970 @item @code{complex?} (default: @var{#f})
35971 Whether the database configuration complex. The complex configuration
35972 will need a corresponding @code{<dicod-handler>} object, otherwise not.
35974 @item @code{options}
35975 List of strings or gexps representing the arguments for the database
35976 (@pxref{Databases,,, dico, GNU Dico Manual}).
35980 @defvr {Scheme Variable} %dicod-database:gcide
35981 A @code{<dicod-database>} object serving the GNU Collaborative International
35982 Dictionary of English using the @code{gcide} package.
35985 The following is an example @code{dicod-service} configuration.
35988 (dicod-service #:config
35989 (dicod-configuration
35990 (handlers (list (dicod-handler
35994 (list #~(string-append "dbdir=" #$wordnet))))))
35995 (databases (list (dicod-database
35998 (handler "wordnet")
35999 (options '("database=wn")))
36000 %dicod-database:gcide))))
36004 @subsubheading Docker Service
36006 The @code{(gnu services docker)} module provides the following services.
36008 @defvr {Scheme Variable} docker-service-type
36010 This is the type of the service that runs @url{https://www.docker.com,Docker},
36011 a daemon that can execute application bundles (sometimes referred to as
36012 ``containers'') in isolated environments.
36016 @deftp {Data Type} docker-configuration
36017 This is the data type representing the configuration of Docker and Containerd.
36021 @item @code{docker} (default: @code{docker})
36022 The Docker daemon package to use.
36024 @item @code{docker-cli} (default: @code{docker-cli})
36025 The Docker client package to use.
36027 @item @code{containerd} (default: @var{containerd})
36028 The Containerd package to use.
36030 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
36031 The Docker user-land networking proxy package to use.
36033 @item @code{enable-proxy?} (default @code{#t})
36034 Enable or disable the use of the Docker user-land networking proxy.
36036 @item @code{debug?} (default @code{#f})
36037 Enable or disable debug output.
36039 @item @code{enable-iptables?} (default @code{#t})
36040 Enable or disable the addition of iptables rules.
36042 @item @code{environment-variables} (default: @code{()})
36043 List of environment variables to set for @command{dockerd}.
36045 This must be a list of strings where each string has the form
36046 @samp{@var{key}=@var{value}} as in this example:
36049 (list "LANGUAGE=eo:ca:eu"
36050 "TMPDIR=/tmp/dockerd")
36056 @cindex Singularity, container service
36057 @defvr {Scheme Variable} singularity-service-type
36058 This is the type of the service that allows you to run
36059 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
36060 create and run application bundles (aka. ``containers''). The value for this
36061 service is the Singularity package to use.
36063 The service does not install a daemon; instead, it installs helper programs as
36064 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
36065 @command{singularity run} and similar commands.
36069 @subsubheading Auditd Service
36071 The @code{(gnu services auditd)} module provides the following service.
36073 @defvr {Scheme Variable} auditd-service-type
36075 This is the type of the service that runs
36076 @url{https://people.redhat.com/sgrubb/audit/,auditd},
36077 a daemon that tracks security-relevant information on your system.
36079 Examples of things that can be tracked:
36089 Failed login attempts
36096 @command{auditctl} from the @code{audit} package can be used in order
36097 to add or remove events to be tracked (until the next reboot).
36098 In order to permanently track events, put the command line arguments
36099 of auditctl into a file called @code{audit.rules} in the configuration
36100 directory (see below).
36101 @command{aureport} from the @code{audit} package can be used in order
36102 to view a report of all recorded events.
36103 The audit daemon by default logs into the file
36104 @file{/var/log/audit.log}.
36108 @deftp {Data Type} auditd-configuration
36109 This is the data type representing the configuration of auditd.
36113 @item @code{audit} (default: @code{audit})
36114 The audit package to use.
36116 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
36117 The directory containing the configuration file for the audit package, which
36118 must be named @code{auditd.conf}, and optionally some audit rules to
36119 instantiate on startup.
36125 @subsubheading R-Shiny service
36127 The @code{(gnu services science)} module provides the following service.
36129 @defvr {Scheme Variable} rshiny-service-type
36131 This is a type of service which is used to run a webapp created with
36132 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
36133 variable and runs the provided script to call @code{runApp}.
36135 @deftp {Data Type} rshiny-configuration
36136 This is the data type representing the configuration of rshiny.
36140 @item @code{package} (default: @code{r-shiny})
36141 The package to use.
36143 @item @code{binary} (defaunlt @code{"rshiny"})
36144 The name of the binary or shell script located at @code{package/bin/} to
36145 run when the service is run.
36147 The common way to create this file is as follows:
36151 (let* ((out (assoc-ref %outputs "out"))
36152 (targetdir (string-append out "/share/" ,name))
36153 (app (string-append out "/bin/" ,name))
36154 (Rbin (search-input-file %build-inputs "/bin/Rscript")))
36156 (mkdir-p (string-append out "/bin"))
36157 (call-with-output-file app
36163 runApp(launch.browser=0, port=4202)~%\n"
36172 @subsubheading Nix service
36174 The @code{(gnu services nix)} module provides the following service.
36176 @defvr {Scheme Variable} nix-service-type
36178 This is the type of the service that runs build daemon of the
36179 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
36183 (use-modules (gnu))
36184 (use-service-modules nix)
36185 (use-package-modules package-management)
36189 (packages (append (list nix)
36192 (services (append (list (service nix-service-type))
36196 After @command{guix system reconfigure} configure Nix for your user:
36199 @item Add a Nix channel and update it. See
36200 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
36202 @item Create a symlink to your profile and activate Nix profile:
36206 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
36207 $ source /run/current-system/profile/etc/profile.d/nix.sh
36212 @deftp {Data Type} nix-configuration
36213 This data type represents the configuration of the Nix daemon.
36216 @item @code{nix} (default: @code{nix})
36217 The Nix package to use.
36219 @item @code{sandbox} (default: @code{#t})
36220 Specifies whether builds are sandboxed by default.
36222 @item @code{build-sandbox-items} (default: @code{'()})
36223 This is a list of strings or objects appended to the
36224 @code{build-sandbox-items} field of the configuration file.
36226 @item @code{extra-config} (default: @code{'()})
36227 This is a list of strings or objects appended to the configuration file.
36228 It is used to pass extra text to be added verbatim to the configuration
36231 @item @code{extra-options} (default: @code{'()})
36232 Extra command line options for @code{nix-service-type}.
36236 @node Setuid Programs
36237 @section Setuid Programs
36239 @cindex setuid programs
36240 @cindex setgid programs
36241 Some programs need to run with elevated privileges, even when they are
36242 launched by unprivileged users. A notorious example is the
36243 @command{passwd} program, which users can run to change their
36244 password, and which needs to access the @file{/etc/passwd} and
36245 @file{/etc/shadow} files---something normally restricted to root, for
36246 obvious security reasons. To address that, @command{passwd} should be
36247 @dfn{setuid-root}, meaning that it always runs with root privileges
36248 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
36249 for more info about the setuid mechanism).
36251 The store itself @emph{cannot} contain setuid programs: that would be a
36252 security issue since any user on the system can write derivations that
36253 populate the store (@pxref{The Store}). Thus, a different mechanism is
36254 used: instead of changing the setuid or setgid bits directly on files that
36255 are in the store, we let the system administrator @emph{declare} which
36256 programs should be entrusted with these additional privileges.
36258 The @code{setuid-programs} field of an @code{operating-system}
36259 declaration contains a list of @code{<setuid-program>} denoting the
36260 names of programs to have a setuid or setgid bit set (@pxref{Using the
36261 Configuration System}). For instance, the @command{mount.nfs} program,
36262 which is part of the nfs-utils package, with a setuid root can be
36263 designated like this:
36267 (program (file-append nfs-utils "/sbin/mount.nfs")))
36270 And then, to make @command{mount.nfs} setuid on your system, add the
36271 previous example to your operating system declaration by appending it to
36272 @code{%setuid-programs} like this:
36276 ;; Some fields omitted...
36278 (append (list (setuid-program
36279 (program (file-append nfs-utils "/sbin/mount.nfs"))))
36280 %setuid-programs)))
36283 @deftp {Data Type} setuid-program
36284 This data type represents a program with a setuid or setgid bit set.
36287 @item @code{program}
36288 A file-like object having its setuid and/or setgid bit set.
36290 @item @code{setuid?} (default: @code{#t})
36291 Whether to set user setuid bit.
36293 @item @code{setgid?} (default: @code{#f})
36294 Whether to set group setgid bit.
36296 @item @code{user} (default: @code{0})
36297 UID (integer) or user name (string) for the user owner of the program,
36300 @item @code{group} (default: @code{0})
36301 GID (integer) goup name (string) for the group owner of the program,
36307 A default set of setuid programs is defined by the
36308 @code{%setuid-programs} variable of the @code{(gnu system)} module.
36310 @defvr {Scheme Variable} %setuid-programs
36311 A list of @code{<setuid-program>} denoting common programs that are
36314 The list includes commands such as @command{passwd}, @command{ping},
36315 @command{su}, and @command{sudo}.
36318 Under the hood, the actual setuid programs are created in the
36319 @file{/run/setuid-programs} directory at system activation time. The
36320 files in this directory refer to the ``real'' binaries, which are in the
36323 @node X.509 Certificates
36324 @section X.509 Certificates
36326 @cindex HTTPS, certificates
36327 @cindex X.509 certificates
36329 Web servers available over HTTPS (that is, HTTP over the transport-layer
36330 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
36331 that the client can then use to @emph{authenticate} the server. To do
36332 that, clients verify that the server's certificate is signed by a
36333 so-called @dfn{certificate authority} (CA). But to verify the CA's
36334 signature, clients must have first acquired the CA's certificate.
36336 Web browsers such as GNU@tie{}IceCat include their own set of CA
36337 certificates, such that they are able to verify CA signatures
36340 However, most other programs that can talk HTTPS---@command{wget},
36341 @command{git}, @command{w3m}, etc.---need to be told where CA
36342 certificates can be found.
36344 @cindex @code{nss-certs}
36345 In Guix, this is done by adding a package that provides certificates
36346 to the @code{packages} field of the @code{operating-system} declaration
36347 (@pxref{operating-system Reference}). Guix includes one such package,
36348 @code{nss-certs}, which is a set of CA certificates provided as part of
36349 Mozilla's Network Security Services.
36351 Note that it is @emph{not} part of @code{%base-packages}, so you need to
36352 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
36353 most applications and libraries look for certificates by default, points
36354 to the certificates installed globally.
36356 Unprivileged users, including users of Guix on a foreign distro,
36357 can also install their own certificate package in
36358 their profile. A number of environment variables need to be defined so
36359 that applications and libraries know where to find them. Namely, the
36360 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
36361 variables. Some applications add their own environment variables; for
36362 instance, the Git version control system honors the certificate bundle
36363 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
36364 would typically run something like:
36367 guix install nss-certs
36368 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
36369 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
36370 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
36373 As another example, R requires the @env{CURL_CA_BUNDLE} environment
36374 variable to point to a certificate bundle, so you would have to run
36375 something like this:
36378 guix install nss-certs
36379 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
36382 For other applications you may want to look up the required environment
36383 variable in the relevant documentation.
36386 @node Name Service Switch
36387 @section Name Service Switch
36389 @cindex name service switch
36391 The @code{(gnu system nss)} module provides bindings to the
36392 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
36393 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
36394 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
36395 extended with new ``name'' lookup methods for system databases, which
36396 includes host names, service names, user accounts, and more (@pxref{Name
36397 Service Switch, System Databases and Name Service Switch,, libc, The GNU
36398 C Library Reference Manual}).
36400 The NSS configuration specifies, for each system database, which lookup
36401 method is to be used, and how the various methods are chained
36402 together---for instance, under which circumstances NSS should try the
36403 next method in the list. The NSS configuration is given in the
36404 @code{name-service-switch} field of @code{operating-system} declarations
36405 (@pxref{operating-system Reference, @code{name-service-switch}}).
36408 @cindex .local, host name lookup
36409 As an example, the declaration below configures the NSS to use the
36410 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
36411 back-end}, which supports host name lookups over multicast DNS (mDNS)
36412 for host names ending in @code{.local}:
36415 (name-service-switch
36416 (hosts (list %files ;first, check /etc/hosts
36418 ;; If the above did not succeed, try
36419 ;; with 'mdns_minimal'.
36421 (name "mdns_minimal")
36423 ;; 'mdns_minimal' is authoritative for
36424 ;; '.local'. When it returns "not found",
36425 ;; no need to try the next methods.
36426 (reaction (lookup-specification
36427 (not-found => return))))
36429 ;; Then fall back to DNS.
36433 ;; Finally, try with the "full" 'mdns'.
36438 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
36439 contains this configuration, so you will not have to type it if all you
36440 want is to have @code{.local} host lookup working.
36442 Note that, in this case, in addition to setting the
36443 @code{name-service-switch} of the @code{operating-system} declaration,
36444 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
36445 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
36446 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
36447 to the name service cache daemon (@pxref{Base Services,
36448 @code{nscd-service}}).
36450 For convenience, the following variables provide typical NSS
36453 @defvr {Scheme Variable} %default-nss
36454 This is the default name service switch configuration, a
36455 @code{name-service-switch} object.
36458 @defvr {Scheme Variable} %mdns-host-lookup-nss
36459 This is the name service switch configuration with support for host name
36460 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
36463 The reference for name service switch configuration is given below. It
36464 is a direct mapping of the configuration file format of the C library , so
36465 please refer to the C library manual for more information (@pxref{NSS
36466 Configuration File,,, libc, The GNU C Library Reference Manual}).
36467 Compared to the configuration file format of libc NSS, it has the advantage
36468 not only of adding this warm parenthetic feel that we like, but also
36469 static checks: you will know about syntax errors and typos as soon as you
36470 run @command{guix system}.
36472 @deftp {Data Type} name-service-switch
36474 This is the data type representation the configuration of libc's name
36475 service switch (NSS). Each field below represents one of the supported
36492 The system databases handled by the NSS@. Each of these fields must be a
36493 list of @code{<name-service>} objects (see below).
36497 @deftp {Data Type} name-service
36499 This is the data type representing an actual name service and the
36500 associated lookup action.
36504 A string denoting the name service (@pxref{Services in the NSS
36505 configuration,,, libc, The GNU C Library Reference Manual}).
36507 Note that name services listed here must be visible to nscd. This is
36508 achieved by passing the @code{#:name-services} argument to
36509 @code{nscd-service} the list of packages providing the needed name
36510 services (@pxref{Base Services, @code{nscd-service}}).
36513 An action specified using the @code{lookup-specification} macro
36514 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
36515 Reference Manual}). For example:
36518 (lookup-specification (unavailable => continue)
36519 (success => return))
36524 @node Initial RAM Disk
36525 @section Initial RAM Disk
36528 @cindex initial RAM disk
36529 For bootstrapping purposes, the Linux-Libre kernel is passed an
36530 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
36531 root file system as well as an initialization script. The latter is
36532 responsible for mounting the real root file system, and for loading any
36533 kernel modules that may be needed to achieve that.
36535 The @code{initrd-modules} field of an @code{operating-system}
36536 declaration allows you to specify Linux-libre kernel modules that must
36537 be available in the initrd. In particular, this is where you would list
36538 modules needed to actually drive the hard disk where your root partition
36539 is---although the default value of @code{initrd-modules} should cover
36540 most use cases. For example, assuming you need the @code{megaraid_sas}
36541 module in addition to the default modules to be able to access your root
36542 file system, you would write:
36547 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
36550 @defvr {Scheme Variable} %base-initrd-modules
36551 This is the list of kernel modules included in the initrd by default.
36554 Furthermore, if you need lower-level customization, the @code{initrd}
36555 field of an @code{operating-system} declaration allows
36556 you to specify which initrd you would like to use. The @code{(gnu
36557 system linux-initrd)} module provides three ways to build an initrd: the
36558 high-level @code{base-initrd} procedure and the low-level
36559 @code{raw-initrd} and @code{expression->initrd} procedures.
36561 The @code{base-initrd} procedure is intended to cover most common uses.
36562 For example, if you want to add a bunch of kernel modules to be loaded
36563 at boot time, you can define the @code{initrd} field of the operating
36564 system declaration like this:
36567 (initrd (lambda (file-systems . rest)
36568 ;; Create a standard initrd but set up networking
36569 ;; with the parameters QEMU expects by default.
36570 (apply base-initrd file-systems
36571 #:qemu-networking? #t
36575 The @code{base-initrd} procedure also handles common use cases that
36576 involves using the system as a QEMU guest, or as a ``live'' system with
36577 volatile root file system.
36579 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
36580 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
36581 such as trying to guess which kernel modules and packages should be included
36582 to the initrd. An example use of @code{raw-initrd} is when a user has
36583 a custom Linux kernel configuration and default kernel modules included by
36584 @code{base-initrd} are not available.
36586 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
36587 honors several options passed on the Linux kernel command line
36588 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
36589 @code{-append} option of QEMU), notably:
36592 @item gnu.load=@var{boot}
36593 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
36594 program, once it has mounted the root file system.
36596 Guix uses this option to yield control to a boot program that runs the
36597 service activation programs and then spawns the GNU@tie{}Shepherd, the
36598 initialization system.
36600 @item root=@var{root}
36601 Mount @var{root} as the root file system. @var{root} can be a device
36602 name like @code{/dev/sda1}, a file system label, or a file system UUID.
36603 When unspecified, the device name from the root file system of the
36604 operating system declaration is used.
36606 @item rootfstype=@var{type}
36607 Set the type of the root file system. It overrides the @code{type}
36608 field of the root file system specified via the @code{operating-system}
36609 declaration, if any.
36611 @item rootflags=@var{options}
36612 Set the mount @emph{options} of the root file system. It overrides the
36613 @code{options} field of the root file system specified via the
36614 @code{operating-system} declaration, if any.
36616 @item fsck.mode=@var{mode}
36617 Whether to check the @var{root} file system for errors before mounting
36618 it. @var{mode} is one of @code{skip} (never check), @code{force} (always
36619 check), or @code{auto} to respect the root file-system object's 'check?'
36620 setting (@pxref{File Systems}) and run a full scan only if the file system
36621 was not cleanly shut down.
36623 @code{auto} is the default if this option is not present or if @var{mode}
36624 is not one of the above.
36626 @item fsck.repair=@var{level}
36627 The level of repairs to perform automatically if errors are found in the
36628 @var{root} file system. @var{level} is one of @code{no} (do not write to
36629 @var{root} at all if possible), @code{yes} (repair as much as possible),
36630 or @code{preen} to repair problems considered safe to repair automatically.
36632 @code{preen} is the default if this option is not present or if @var{level}
36633 is not one of the above.
36635 @item gnu.system=@var{system}
36636 Have @file{/run/booted-system} and @file{/run/current-system} point to
36639 @item modprobe.blacklist=@var{modules}@dots{}
36640 @cindex module, black-listing
36641 @cindex black list, of kernel modules
36642 Instruct the initial RAM disk as well as the @command{modprobe} command
36643 (from the kmod package) to refuse to load @var{modules}. @var{modules}
36644 must be a comma-separated list of module names---e.g.,
36645 @code{usbkbd,9pnet}.
36648 Start a read-eval-print loop (REPL) from the initial RAM disk before it
36649 tries to load kernel modules and to mount the root file system. Our
36650 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
36651 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
36652 Manual}, for more information on Guile's REPL.
36656 Now that you know all the features that initial RAM disks produced by
36657 @code{base-initrd} and @code{raw-initrd} provide,
36658 here is how to use it and customize it further.
36661 @cindex initial RAM disk
36662 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
36663 [#:linux-modules '()] [#:mapped-devices '()] @
36664 [#:keyboard-layout #f] @
36665 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
36666 Return a derivation that builds a raw initrd. @var{file-systems} is
36667 a list of file systems to be mounted by the initrd, possibly in addition to
36668 the root file system specified on the kernel command line via @option{root}.
36669 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
36670 @var{mapped-devices} is a list of device mappings to realize before
36671 @var{file-systems} are mounted (@pxref{Mapped Devices}).
36672 @var{helper-packages} is a list of packages to be copied in the initrd.
36674 include @code{e2fsck/static} or other packages needed by the initrd to check
36675 the root file system.
36677 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
36678 the desired console keyboard layout. This is done before @var{mapped-devices}
36679 are set up and before @var{file-systems} are mounted such that, should the
36680 user need to enter a passphrase or use the REPL, this happens using the
36681 intended keyboard layout.
36683 When @var{qemu-networking?} is true, set up networking with the standard QEMU
36684 parameters. When @var{virtio?} is true, load additional modules so that the
36685 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
36687 When @var{volatile-root?} is true, the root file system is writable but any changes
36691 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
36692 [#:mapped-devices '()] [#:keyboard-layout #f] @
36693 [#:qemu-networking? #f] [#:volatile-root? #f] @
36694 [#:linux-modules '()]
36695 Return as a file-like object a generic initrd, with kernel
36696 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
36697 mounted by the initrd, possibly in addition to the root file system specified
36698 on the kernel command line via @option{root}. @var{mapped-devices} is a list of device
36699 mappings to realize before @var{file-systems} are mounted.
36701 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
36702 the desired console keyboard layout. This is done before @var{mapped-devices}
36703 are set up and before @var{file-systems} are mounted such that, should the
36704 user need to enter a passphrase or use the REPL, this happens using the
36705 intended keyboard layout.
36707 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
36709 The initrd is automatically populated with all the kernel modules necessary
36710 for @var{file-systems} and for the given options. Additional kernel
36711 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
36712 loaded at boot time in the order in which they appear.
36715 Needless to say, the initrds we produce and use embed a
36716 statically-linked Guile, and the initialization program is a Guile
36717 program. That gives a lot of flexibility. The
36718 @code{expression->initrd} procedure builds such an initrd, given the
36719 program to run in that initrd.
36721 @deffn {Scheme Procedure} expression->initrd @var{exp} @
36722 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
36723 Return as a file-like object a Linux initrd (a gzipped cpio archive)
36724 containing @var{guile} and that evaluates @var{exp}, a G-expression,
36725 upon booting. All the derivations referenced by @var{exp} are
36726 automatically copied to the initrd.
36729 @node Bootloader Configuration
36730 @section Bootloader Configuration
36733 @cindex boot loader
36735 The operating system supports multiple bootloaders. The bootloader is
36736 configured using @code{bootloader-configuration} declaration. All the
36737 fields of this structure are bootloader agnostic except for one field,
36738 @code{bootloader} that indicates the bootloader to be configured and
36741 Some of the bootloaders do not honor every field of
36742 @code{bootloader-configuration}. For instance, the extlinux
36743 bootloader does not support themes and thus ignores the @code{theme}
36746 @deftp {Data Type} bootloader-configuration
36747 The type of a bootloader configuration declaration.
36751 @item @code{bootloader}
36752 @cindex EFI, bootloader
36753 @cindex UEFI, bootloader
36754 @cindex BIOS, bootloader
36755 The bootloader to use, as a @code{bootloader} object. For now
36756 @code{grub-bootloader}, @code{grub-efi-bootloader},
36757 @code{grub-efi-netboot-bootloader}, @code{grub-efi-removable-bootloader},
36758 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
36760 @cindex ARM, bootloaders
36761 @cindex AArch64, bootloaders
36762 Available bootloaders are described in @code{(gnu bootloader @dots{})}
36763 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
36764 of bootloaders for a wide range of ARM and AArch64 systems, using the
36765 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
36767 @vindex grub-efi-bootloader
36768 @code{grub-efi-bootloader} allows to boot on modern systems using the
36769 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
36770 use if the installation image contains a @file{/sys/firmware/efi} directory
36771 when you boot it on your system.
36773 @vindex grub-bootloader
36774 @code{grub-bootloader} allows you to boot in particular Intel-based machines
36775 in ``legacy'' BIOS mode.
36777 @vindex grub-efi-netboot-bootloader
36778 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
36779 through TFTP@. In combination with an NFS root file system this allows you to
36780 build a diskless Guix system.
36782 The installation of the @code{grub-efi-netboot-bootloader} generates the
36783 content of the TFTP root directory at @code{targets} (@pxref{Bootloader
36784 Configuration, @code{targets}}), to be served by a TFTP server. You may
36785 want to mount your TFTP server directories onto the @code{targets} to
36786 move the required files to the TFTP server automatically.
36788 If you plan to use an NFS root file system as well (actually if you mount the
36789 store from an NFS share), then the TFTP server needs to serve the file
36790 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
36791 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
36792 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
36793 files from the store will be accessed by GRUB through TFTP with their normal
36794 store path, for example as
36795 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
36797 Two symlinks are created to make this possible. For each target in the
36798 @code{targets} field, the first symlink is
36799 @samp{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
36800 @file{../../../boot/grub/grub.cfg}, where @samp{target} may be
36801 @file{/boot}. In this case the link is not leaving the served TFTP root
36802 directory, but otherwise it does. The second link is
36803 @samp{target}@file{/gnu/store} and points to @file{../gnu/store}. This
36804 link is leaving the served TFTP root directory.
36806 The assumption behind all this is that you have an NFS server exporting
36807 the root file system for your Guix system, and additionally a TFTP
36808 server exporting your @code{targets} directories—usually a single
36809 @file{/boot}—from that same root file system for your Guix system. In
36810 this constellation the symlinks will work.
36812 For other constellations you will have to program your own bootloader
36813 installer, which then takes care to make necessary files from the store
36814 accessible through TFTP, for example by copying them into the TFTP root
36815 directory to your @code{targets}.
36817 It is important to note that symlinks pointing outside the TFTP root directory
36818 may need to be allowed in the configuration of your TFTP server. Further the
36819 store link exposes the whole store through TFTP@. Both points need to be
36820 considered carefully for security aspects.
36822 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
36823 NFS servers, you also need a properly configured DHCP server to make the booting
36824 over netboot possible. For all this we can currently only recommend you to look
36825 for instructions about @acronym{PXE, Preboot eXecution Environment}.
36827 @vindex grub-efi-removable-bootloader
36828 @code{grub-efi-removable-bootloader} allows you to boot your system from
36829 removable media by writing the GRUB file to the UEFI-specification location of
36830 @file{/EFI/BOOT/BOOTX64.efi} of the boot directory, usually @file{/boot/efi}.
36831 This is also useful for some UEFI firmwares that ``forget'' their configuration
36832 from their non-volatile storage. Like @code{grub-efi-bootloader}, this can only
36833 be used if the @file{/sys/firmware/efi} directory is available.
36836 This @emph{will} overwrite the GRUB file from any other operating systems that
36837 also place their GRUB file in the UEFI-specification location; making them
36841 @item @code{targets}
36842 This is a list of strings denoting the targets onto which to install the
36845 The interpretation of targets depends on the bootloader in question.
36846 For @code{grub-bootloader}, for example, they should be device names
36847 understood by the bootloader @command{installer} command, such as
36848 @code{/dev/sda} or @code{(hd0)} (@pxref{Invoking grub-install,,, grub,
36849 GNU GRUB Manual}). For @code{grub-efi-bootloader} and
36850 @code{grub-efi-removable-bootloader} they should be mount
36851 points of the EFI file system, usually @file{/boot/efi}. For
36852 @code{grub-efi-netboot-bootloader}, @code{targets} should be the mount
36853 points corresponding to TFTP root directories served by your TFTP
36856 @item @code{menu-entries} (default: @code{()})
36857 A possibly empty list of @code{menu-entry} objects (see below), denoting
36858 entries to appear in the bootloader menu, in addition to the current
36859 system entry and the entry pointing to previous system generations.
36861 @item @code{default-entry} (default: @code{0})
36862 The index of the default boot menu entry. Index 0 is for the entry of the
36865 @item @code{timeout} (default: @code{5})
36866 The number of seconds to wait for keyboard input before booting. Set to
36867 0 to boot immediately, and to -1 to wait indefinitely.
36869 @cindex keyboard layout, for the bootloader
36870 @item @code{keyboard-layout} (default: @code{#f})
36871 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
36872 layout, usually US@tie{}English (``qwerty'').
36874 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
36878 This option is currently ignored by bootloaders other than @code{grub} and
36882 @item @code{theme} (default: @var{#f})
36883 The bootloader theme object describing the theme to use. If no theme
36884 is provided, some bootloaders might use a default theme, that's true
36887 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
36888 The output terminals used for the bootloader boot menu, as a list of
36889 symbols. GRUB accepts the values: @code{console}, @code{serial},
36890 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
36891 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
36892 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
36893 configuration,,, grub,GNU GRUB manual}).
36895 @item @code{terminal-inputs} (default: @code{'()})
36896 The input terminals used for the bootloader boot menu, as a list of
36897 symbols. For GRUB, the default is the native platform terminal as
36898 determined at run-time. GRUB accepts the values: @code{console},
36899 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
36900 @code{usb_keyboard}. This field corresponds to the GRUB variable
36901 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
36904 @item @code{serial-unit} (default: @code{#f})
36905 The serial unit used by the bootloader, as an integer from 0 to 3.
36906 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
36907 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
36909 @item @code{serial-speed} (default: @code{#f})
36910 The speed of the serial interface, as an integer. For GRUB, the
36911 default value is chosen at run-time; currently GRUB chooses
36912 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
36919 Should you want to list additional boot menu entries @i{via} the
36920 @code{menu-entries} field above, you will need to create them with the
36921 @code{menu-entry} form. For example, imagine you want to be able to
36922 boot another distro (hard to imagine!), you can define a menu entry
36927 (label "The Other Distro")
36928 (linux "/boot/old/vmlinux-2.6.32")
36929 (linux-arguments '("root=/dev/sda2"))
36930 (initrd "/boot/old/initrd"))
36935 @deftp {Data Type} menu-entry
36936 The type of an entry in the bootloader menu.
36941 The label to show in the menu---e.g., @code{"GNU"}.
36943 @item @code{linux} (default: @code{#f})
36944 The Linux kernel image to boot, for example:
36947 (file-append linux-libre "/bzImage")
36950 For GRUB, it is also possible to specify a device explicitly in the
36951 file path using GRUB's device naming convention (@pxref{Naming
36952 convention,,, grub, GNU GRUB manual}), for example:
36955 "(hd0,msdos1)/boot/vmlinuz"
36958 If the device is specified explicitly as above, then the @code{device}
36959 field is ignored entirely.
36961 @item @code{linux-arguments} (default: @code{()})
36962 The list of extra Linux kernel command-line arguments---e.g.,
36963 @code{("console=ttyS0")}.
36965 @item @code{initrd} (default: @code{#f})
36966 A G-Expression or string denoting the file name of the initial RAM disk
36967 to use (@pxref{G-Expressions}).
36969 @item @code{device} (default: @code{#f})
36970 The device where the kernel and initrd are to be found---i.e., for GRUB,
36971 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
36973 This may be a file system label (a string), a file system UUID (a
36974 bytevector, @pxref{File Systems}), or @code{#f}, in which case
36975 the bootloader will search the device containing the file specified by
36976 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
36977 must @emph{not} be an OS device name such as @file{/dev/sda1}.
36979 @item @code{multiboot-kernel} (default: @code{#f})
36980 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
36981 manual}). When this field is set, a Multiboot menu-entry is generated.
36985 (file-append mach "/boot/gnumach")
36988 @item @code{multiboot-arguments} (default: @code{()})
36989 The list of extra command-line arguments for the multiboot-kernel.
36991 @item @code{multiboot-modules} (default: @code{()})
36992 The list of commands for loading Multiboot modules. For example:
36995 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
36997 (list (file-append libc "/lib/ld.so.1") "exec"
37007 @c FIXME: Write documentation once it's stable.
37008 For now only GRUB has theme support. GRUB themes are created using
37009 the @code{grub-theme} form, which is not fully documented yet.
37011 @deftp {Data Type} grub-theme
37012 Data type representing the configuration of the GRUB theme.
37015 @item @code{gfxmode} (default: @code{'("auto")})
37016 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
37017 @pxref{gfxmode,,, grub, GNU GRUB manual}).
37021 @deffn {Scheme Procedure} grub-theme
37022 Return the default GRUB theme used by the operating system if no
37023 @code{theme} field is specified in @code{bootloader-configuration}
37026 It comes with a fancy background image displaying the GNU and Guix
37030 For example, to override the default resolution, you may use something
37035 (bootloader-configuration
37038 (inherit (grub-theme))
37039 (gfxmode '("1024x786x32" "auto"))))))
37042 @node Invoking guix system
37043 @section Invoking @code{guix system}
37045 Once you have written an operating system declaration as seen in the
37046 previous section, it can be @dfn{instantiated} using the @command{guix
37047 system} command. The synopsis is:
37050 guix system @var{options}@dots{} @var{action} @var{file}
37053 @var{file} must be the name of a file containing an
37054 @code{operating-system} declaration. @var{action} specifies how the
37055 operating system is instantiated. Currently the following values are
37060 Display available service type definitions that match the given regular
37061 expressions, sorted by relevance:
37067 $ guix system search console
37068 name: console-fonts
37069 location: gnu/services/base.scm:806:2
37070 extends: shepherd-root
37071 description: Install the given fonts on the specified ttys (fonts are per
37072 + virtual console on GNU/Linux). The value of this service is a list of
37073 + tty/font pairs. The font can be the name of a font provided by the `kbd'
37074 + package or any valid argument to `setfont', as in this example:
37076 + '(("tty1" . "LatGrkCyr-8x16")
37077 + ("tty2" . (file-append
37079 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
37080 + ("tty3" . (file-append
37082 + "/share/consolefonts/ter-132n"))) ; for HDPI
37086 location: gnu/services/base.scm:1190:2
37087 extends: shepherd-root
37088 description: Provide console login using the `mingetty' program.
37092 location: gnu/services/base.scm:860:2
37094 description: Provide a console log-in service as specified by its
37095 + configuration value, a `login-configuration' object.
37101 As for @command{guix package --search}, the result is written in
37102 @code{recutils} format, which makes it easy to filter the output
37103 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
37105 @cindex service type definition, editing
37106 @cindex editing, service type definition
37108 Edit or view the definition of the given service types.
37110 For example, the command below opens your editor, as specified by the
37111 @env{EDITOR} environment variable, on the definition of the
37112 @code{openssh} service type:
37115 guix system edit openssh
37119 Build the operating system described in @var{file}, activate it, and
37120 switch to it@footnote{This action (and the related actions
37121 @code{switch-generation} and @code{roll-back}) are usable only on
37122 systems already running Guix System.}.
37125 @c The paragraph below refers to the problem discussed at
37126 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
37127 It is highly recommended to run @command{guix pull} once before you run
37128 @command{guix system reconfigure} for the first time (@pxref{Invoking
37129 guix pull}). Failing to do that you would see an older version of Guix
37130 once @command{reconfigure} has completed.
37133 This effects all the configuration specified in @var{file}: user
37134 accounts, system services, global package list, setuid programs, etc.
37135 The command starts system services specified in @var{file} that are not
37136 currently running; if a service is currently running this command will
37137 arrange for it to be upgraded the next time it is stopped (e.g.@: by
37138 @code{herd stop X} or @code{herd restart X}).
37140 This command creates a new generation whose number is one greater than
37141 the current generation (as reported by @command{guix system
37142 list-generations}). If that generation already exists, it will be
37143 overwritten. This behavior mirrors that of @command{guix package}
37144 (@pxref{Invoking guix package}).
37146 It also adds a bootloader menu entry for the new OS configuration,
37147 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
37148 entries for older configurations to a submenu, allowing you to choose
37149 an older system generation at boot time should you need it.
37151 @cindex provenance tracking, of the operating system
37152 Upon completion, the new system is deployed under
37153 @file{/run/current-system}. This directory contains @dfn{provenance
37154 meta-data}: the list of channels in use (@pxref{Channels}) and
37155 @var{file} itself, when available. You can view it by running:
37158 guix system describe
37161 This information is useful should you later want to inspect how this
37162 particular generation was built. In fact, assuming @var{file} is
37163 self-contained, you can later rebuild generation @var{n} of your
37164 operating system with:
37167 guix time-machine \
37168 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
37169 system reconfigure \
37170 /var/guix/profiles/system-@var{n}-link/configuration.scm
37173 You can think of it as some sort of built-in version control! Your
37174 system is not just a binary artifact: @emph{it carries its own source}.
37175 @xref{Service Reference, @code{provenance-service-type}}, for more
37176 information on provenance tracking.
37178 By default, @command{reconfigure} @emph{prevents you from downgrading
37179 your system}, which could (re)introduce security vulnerabilities and
37180 also cause problems with ``stateful'' services such as database
37181 management systems. You can override that behavior by passing
37182 @option{--allow-downgrades}.
37184 @item switch-generation
37185 @cindex generations
37186 Switch to an existing system generation. This action atomically
37187 switches the system profile to the specified system generation. It
37188 also rearranges the system's existing bootloader menu entries. It
37189 makes the menu entry for the specified system generation the default,
37190 and it moves the entries for the other generations to a submenu, if
37191 supported by the bootloader being used. The next time the system
37192 boots, it will use the specified system generation.
37194 The bootloader itself is not being reinstalled when using this
37195 command. Thus, the installed bootloader is used with an updated
37196 configuration file.
37198 The target generation can be specified explicitly by its generation
37199 number. For example, the following invocation would switch to system
37203 guix system switch-generation 7
37206 The target generation can also be specified relative to the current
37207 generation with the form @code{+N} or @code{-N}, where @code{+3} means
37208 ``3 generations ahead of the current generation,'' and @code{-1} means
37209 ``1 generation prior to the current generation.'' When specifying a
37210 negative value such as @code{-1}, you must precede it with @code{--} to
37211 prevent it from being parsed as an option. For example:
37214 guix system switch-generation -- -1
37217 Currently, the effect of invoking this action is @emph{only} to switch
37218 the system profile to an existing generation and rearrange the
37219 bootloader menu entries. To actually start using the target system
37220 generation, you must reboot after running this action. In the future,
37221 it will be updated to do the same things as @command{reconfigure},
37222 like activating and deactivating services.
37224 This action will fail if the specified generation does not exist.
37227 @cindex rolling back
37228 Switch to the preceding system generation. The next time the system
37229 boots, it will use the preceding system generation. This is the inverse
37230 of @command{reconfigure}, and it is exactly the same as invoking
37231 @command{switch-generation} with an argument of @code{-1}.
37233 Currently, as with @command{switch-generation}, you must reboot after
37234 running this action to actually start using the preceding system
37237 @item delete-generations
37238 @cindex deleting system generations
37239 @cindex saving space
37240 Delete system generations, making them candidates for garbage collection
37241 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
37244 This works in the same way as @samp{guix package --delete-generations}
37245 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
37246 arguments, all system generations but the current one are deleted:
37249 guix system delete-generations
37252 You can also select the generations you want to delete. The example below
37253 deletes all the system generations that are more than two months old:
37256 guix system delete-generations 2m
37259 Running this command automatically reinstalls the bootloader with an updated
37260 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
37261 longer lists the generations that have been deleted.
37264 Build the derivation of the operating system, which includes all the
37265 configuration files and programs needed to boot and run the system.
37266 This action does not actually install anything.
37269 Populate the given directory with all the files necessary to run the
37270 operating system specified in @var{file}. This is useful for first-time
37271 installations of Guix System. For instance:
37274 guix system init my-os-config.scm /mnt
37277 copies to @file{/mnt} all the store items required by the configuration
37278 specified in @file{my-os-config.scm}. This includes configuration
37279 files, packages, and so on. It also creates other essential files
37280 needed for the system to operate correctly---e.g., the @file{/etc},
37281 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
37283 This command also installs bootloader on the targets specified in
37284 @file{my-os-config}, unless the @option{--no-bootloader} option was
37288 @cindex virtual machine
37290 @anchor{guix system vm}
37291 Build a virtual machine (VM) that contains the operating system declared
37292 in @var{file}, and return a script to run that VM.
37295 The @code{vm} action and others below
37296 can use KVM support in the Linux-libre kernel. Specifically, if the
37297 machine has hardware virtualization support, the corresponding
37298 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
37299 must exist and be readable and writable by the user and by the
37300 build users of the daemon (@pxref{Build Environment Setup}).
37303 Arguments given to the script are passed to QEMU as in the example
37304 below, which enables networking and requests 1@tie{}GiB of RAM for the
37308 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -nic user,model=virtio-net-pci
37311 It's possible to combine the two steps into one:
37314 $ $(guix system vm my-config.scm) -m 1024 -smp 2 -nic user,model=virtio-net-pci
37317 The VM shares its store with the host system.
37319 By default, the root file system of the VM is mounted volatile; the
37320 @option{--persistent} option can be provided to make it persistent
37321 instead. In that case, the VM disk-image file will be copied from the
37322 store to the @env{TMPDIR} directory to make it writable.
37324 Additional file systems can be shared between the host and the VM using
37325 the @option{--share} and @option{--expose} command-line options: the former
37326 specifies a directory to be shared with write access, while the latter
37327 provides read-only access to the shared directory.
37329 The example below creates a VM in which the user's home directory is
37330 accessible read-only, and where the @file{/exchange} directory is a
37331 read-write mapping of @file{$HOME/tmp} on the host:
37334 guix system vm my-config.scm \
37335 --expose=$HOME --share=$HOME/tmp=/exchange
37338 On GNU/Linux, the default is to boot directly to the kernel; this has
37339 the advantage of requiring only a very tiny root disk image since the
37340 store of the host can then be mounted.
37342 The @option{--full-boot} option forces a complete boot sequence, starting
37343 with the bootloader. This requires more disk space since a root image
37344 containing at least the kernel, initrd, and bootloader data files must
37347 The @option{--image-size} option can be used to specify the size of the
37350 The @option{--no-graphic} option will instruct @command{guix system} to
37351 spawn a headless VM that will use the invoking tty for IO. Among other
37352 things, this enables copy-pasting, and scrollback. Use the @kbd{ctrl-a}
37353 prefix to issue QEMU commands; e.g. @kbd{ctrl-a h} prints a help,
37354 @kbd{ctrl-a x} quits the VM, and @kbd{ctrl-a c} switches between the
37355 QEMU monitor and the VM.
37357 @cindex System images, creation in various formats
37358 @cindex Creating system images in various formats
37360 @cindex image, creating disk images
37361 The @code{image} command can produce various image types. The image
37362 type can be selected using the @option{--image-type} option. It
37363 defaults to @code{efi-raw}. When its value is @code{iso9660}, the
37364 @option{--label} option can be used to specify a volume ID with
37365 @code{image}. By default, the root file system of a disk image is
37366 mounted non-volatile; the @option{--volatile} option can be provided to
37367 make it volatile instead. When using @code{image}, the bootloader
37368 installed on the generated image is taken from the provided
37369 @code{operating-system} definition. The following example demonstrates
37370 how to generate an image that uses the @code{grub-efi-bootloader}
37371 bootloader and boot it with QEMU:
37374 image=$(guix system image --image-type=qcow2 \
37375 gnu/system/examples/lightweight-desktop.tmpl)
37376 cp $image /tmp/my-image.qcow2
37377 chmod +w /tmp/my-image.qcow2
37378 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
37379 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
37382 When using the @code{efi-raw} image type, a raw disk image is produced;
37383 it can be copied as is to a USB stick, for instance. Assuming
37384 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
37385 the image to it using the following command:
37388 # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
37391 The @code{--list-image-types} command lists all the available image
37394 @cindex creating virtual machine images
37395 When using the @code{qcow2} image type, the returned image is in qcow2
37396 format, which the QEMU emulator can efficiently use. @xref{Running Guix
37397 in a VM}, for more information on how to run the image in a virtual
37398 machine. The @code{grub-bootloader} bootloader is always used
37399 independently of what is declared in the @code{operating-system} file
37400 passed as argument. This is to make it easier to work with QEMU, which
37401 uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
37402 in the Master Boot Record (MBR).
37404 @cindex docker-image, creating docker images
37405 When using the @code{docker} image type, a Docker image is produced.
37406 Guix builds the image from scratch, not from a pre-existing Docker base
37407 image. As a result, it contains @emph{exactly} what you define in the
37408 operating system configuration file. You can then load the image and
37409 launch a Docker container using commands like the following:
37412 image_id="$(docker load < guix-system-docker-image.tar.gz)"
37413 container_id="$(docker create $image_id)"
37414 docker start $container_id
37417 This command starts a new Docker container from the specified image. It
37418 will boot the Guix system in the usual manner, which means it will
37419 start any services you have defined in the operating system
37420 configuration. You can get an interactive shell running in the container
37421 using @command{docker exec}:
37424 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
37427 Depending on what you run in the Docker container, it
37428 may be necessary to give the container additional permissions. For
37429 example, if you intend to build software using Guix inside of the Docker
37430 container, you may need to pass the @option{--privileged} option to
37431 @code{docker create}.
37433 Last, the @option{--network} option applies to @command{guix system
37434 docker-image}: it produces an image where network is supposedly shared
37435 with the host, and thus without services like nscd or NetworkManager.
37438 Return a script to run the operating system declared in @var{file}
37439 within a container. Containers are a set of lightweight isolation
37440 mechanisms provided by the kernel Linux-libre. Containers are
37441 substantially less resource-demanding than full virtual machines since
37442 the kernel, shared objects, and other resources can be shared with the
37443 host system; this also means they provide thinner isolation.
37445 Currently, the script must be run as root in order to support more than
37446 a single user and group. The container shares its store with the host
37449 As with the @code{vm} action (@pxref{guix system vm}), additional file
37450 systems to be shared between the host and container can be specified
37451 using the @option{--share} and @option{--expose} options:
37454 guix system container my-config.scm \
37455 --expose=$HOME --share=$HOME/tmp=/exchange
37459 This option requires Linux-libre 3.19 or newer.
37464 @var{options} can contain any of the common build options (@pxref{Common
37465 Build Options}). In addition, @var{options} can contain one of the
37469 @item --expression=@var{expr}
37470 @itemx -e @var{expr}
37471 Consider the operating-system @var{expr} evaluates to.
37472 This is an alternative to specifying a file which evaluates to an
37474 This is used to generate the Guix system installer @pxref{Building the
37475 Installation Image}).
37477 @item --system=@var{system}
37478 @itemx -s @var{system}
37479 Attempt to build for @var{system} instead of the host system type.
37480 This works as per @command{guix build} (@pxref{Invoking guix build}).
37484 Return the derivation file name of the given operating system without
37487 @cindex provenance tracking, of the operating system
37488 @item --save-provenance
37489 As discussed above, @command{guix system init} and @command{guix system
37490 reconfigure} always save provenance information @i{via} a dedicated
37491 service (@pxref{Service Reference, @code{provenance-service-type}}).
37492 However, other commands don't do that by default. If you wish to, say,
37493 create a virtual machine image that contains provenance information, you
37497 guix system image -t qcow2 --save-provenance config.scm
37500 That way, the resulting image will effectively ``embed its own source''
37501 in the form of meta-data in @file{/run/current-system}. With that
37502 information, one can rebuild the image to make sure it really contains
37503 what it pretends to contain; or they could use that to derive a variant
37506 @item --image-type=@var{type}
37507 @itemx -t @var{type}
37508 For the @code{image} action, create an image with given @var{type}.
37510 When this option is omitted, @command{guix system} uses the
37511 @code{efi-raw} image type.
37513 @cindex ISO-9660 format
37514 @cindex CD image format
37515 @cindex DVD image format
37516 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
37517 for burning on CDs and DVDs.
37519 @item --image-size=@var{size}
37520 For the @code{image} action, create an image of the given @var{size}.
37521 @var{size} may be a number of bytes, or it may include a unit as a
37522 suffix (@pxref{Block size, size specifications,, coreutils, GNU
37525 When this option is omitted, @command{guix system} computes an estimate
37526 of the image size as a function of the size of the system declared in
37531 For the @code{container} action, allow containers to access the host network,
37532 that is, do not create a network namespace.
37534 @item --root=@var{file}
37535 @itemx -r @var{file}
37536 Make @var{file} a symlink to the result, and register it as a garbage
37539 @item --skip-checks
37540 Skip pre-installation safety checks.
37542 By default, @command{guix system init} and @command{guix system
37543 reconfigure} perform safety checks: they make sure the file systems that
37544 appear in the @code{operating-system} declaration actually exist
37545 (@pxref{File Systems}), and that any Linux kernel modules that may be
37546 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
37547 RAM Disk}). Passing this option skips these tests altogether.
37549 @item --allow-downgrades
37550 Instruct @command{guix system reconfigure} to allow system downgrades.
37552 By default, @command{reconfigure} prevents you from downgrading your
37553 system. It achieves that by comparing the provenance info of your
37554 system (shown by @command{guix system describe}) with that of your
37555 @command{guix} command (shown by @command{guix describe}). If the
37556 commits for @command{guix} are not descendants of those used for your
37557 system, @command{guix system reconfigure} errors out. Passing
37558 @option{--allow-downgrades} allows you to bypass these checks.
37561 Make sure you understand its security implications before using
37562 @option{--allow-downgrades}.
37566 @cindex on-error strategy
37567 @cindex error strategy
37568 @item --on-error=@var{strategy}
37569 Apply @var{strategy} when an error occurs when reading @var{file}.
37570 @var{strategy} may be one of the following:
37573 @item nothing-special
37574 Report the error concisely and exit. This is the default strategy.
37577 Likewise, but also display a backtrace.
37580 Report the error and enter Guile's debugger. From there, you can run
37581 commands such as @code{,bt} to get a backtrace, @code{,locals} to
37582 display local variable values, and more generally inspect the state of the
37583 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
37584 a list of available debugging commands.
37588 Once you have built, configured, re-configured, and re-re-configured
37589 your Guix installation, you may find it useful to list the operating
37590 system generations available on disk---and that you can choose from the
37591 bootloader boot menu:
37596 Describe the running system generation: its file name, the kernel and
37597 bootloader used, etc., as well as provenance information when available.
37599 The @code{--list-installed} flag is available, with the same
37600 syntax that is used in @command{guix package --list-installed}
37601 (@pxref{Invoking guix package}). When the flag is used,
37602 the description will include a list of packages that are currently
37603 installed in the system profile, with optional filtering based on a
37604 regular expression.
37607 The @emph{running} system generation---referred to by
37608 @file{/run/current-system}---is not necessarily the @emph{current}
37609 system generation---referred to by @file{/var/guix/profiles/system}: it
37610 differs when, for instance, you chose from the bootloader menu to boot
37611 an older generation.
37613 It can also differ from the @emph{booted} system generation---referred
37614 to by @file{/run/booted-system}---for instance because you reconfigured
37615 the system in the meantime.
37618 @item list-generations
37619 List a summary of each generation of the operating system available on
37620 disk, in a human-readable way. This is similar to the
37621 @option{--list-generations} option of @command{guix package}
37622 (@pxref{Invoking guix package}).
37624 Optionally, one can specify a pattern, with the same syntax that is used
37625 in @command{guix package --list-generations}, to restrict the list of
37626 generations displayed. For instance, the following command displays
37627 generations that are up to 10 days old:
37630 $ guix system list-generations 10d
37633 The @code{--list-installed} flag may also be specified, with the same
37634 syntax that is used in @command{guix package --list-installed}. This
37635 may be helpful if trying to determine when a package was added to the
37640 The @command{guix system} command has even more to offer! The following
37641 sub-commands allow you to visualize how your system services relate to
37644 @anchor{system-extension-graph}
37647 @item extension-graph
37648 Emit to standard output the @dfn{service
37649 extension graph} of the operating system defined in @var{file}
37650 (@pxref{Service Composition}, for more information on service
37651 extensions). By default the output is in Dot/Graphviz format, but you
37652 can choose a different format with @option{--graph-backend}, as with
37653 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
37658 $ guix system extension-graph @var{file} | xdot -
37661 shows the extension relations among services.
37664 The @command{dot} program is provided by the @code{graphviz} package.
37667 @anchor{system-shepherd-graph}
37668 @item shepherd-graph
37669 Emit to standard output the @dfn{dependency
37670 graph} of shepherd services of the operating system defined in
37671 @var{file}. @xref{Shepherd Services}, for more information and for an
37674 Again, the default output format is Dot/Graphviz, but you can pass
37675 @option{--graph-backend} to select a different one.
37679 @node Invoking guix deploy
37680 @section Invoking @code{guix deploy}
37682 We've already seen @code{operating-system} declarations used to manage a
37683 machine's configuration locally. Suppose you need to configure multiple
37684 machines, though---perhaps you're managing a service on the web that's
37685 comprised of several servers. @command{guix deploy} enables you to use those
37686 same @code{operating-system} declarations to manage multiple remote hosts at
37687 once as a logical ``deployment''.
37690 The functionality described in this section is still under development
37691 and is subject to change. Get in touch with us on
37692 @email{guix-devel@@gnu.org}!
37696 guix deploy @var{file}
37699 Such an invocation will deploy the machines that the code within @var{file}
37700 evaluates to. As an example, @var{file} might contain a definition like this:
37703 ;; This is a Guix deployment of a "bare bones" setup, with
37704 ;; no X11 display server, to a machine with an SSH daemon
37705 ;; listening on localhost:2222. A configuration such as this
37706 ;; may be appropriate for virtual machine with ports
37707 ;; forwarded to the host's loopback interface.
37709 (use-service-modules networking ssh)
37710 (use-package-modules bootloaders)
37714 (host-name "gnu-deployed")
37715 (timezone "Etc/UTC")
37716 (bootloader (bootloader-configuration
37717 (bootloader grub-bootloader)
37718 (targets '("/dev/vda"))
37719 (terminal-outputs '(console))))
37720 (file-systems (cons (file-system
37722 (device "/dev/vda1")
37724 %base-file-systems))
37726 (append (list (service dhcp-client-service-type)
37727 (service openssh-service-type
37728 (openssh-configuration
37729 (permit-root-login #t)
37730 (allow-empty-passwords? #t))))
37734 (operating-system %system)
37735 (environment managed-host-environment-type)
37736 (configuration (machine-ssh-configuration
37737 (host-name "localhost")
37738 (system "x86_64-linux")
37740 (identity "./id_rsa")
37744 The file should evaluate to a list of @var{machine} objects. This example,
37745 upon being deployed, will create a new generation on the remote system
37746 realizing the @code{operating-system} declaration @code{%system}.
37747 @code{environment} and @code{configuration} specify how the machine should be
37748 provisioned---that is, how the computing resources should be created and
37749 managed. The above example does not create any resources, as a
37750 @code{'managed-host} is a machine that is already running the Guix system and
37751 available over the network. This is a particularly simple case; a more
37752 complex deployment may involve, for example, starting virtual machines through
37753 a Virtual Private Server (VPS) provider. In such a case, a different
37754 @var{environment} type would be used.
37756 Do note that you first need to generate a key pair on the coordinator machine
37757 to allow the daemon to export signed archives of files from the store
37758 (@pxref{Invoking guix archive}), though this step is automatic on Guix
37762 # guix archive --generate-key
37766 Each target machine must authorize the key of the master machine so that it
37767 accepts store items it receives from the coordinator:
37770 # guix archive --authorize < coordinator-public-key.txt
37773 @code{user}, in this example, specifies the name of the user account to log in
37774 as to perform the deployment. Its default value is @code{root}, but root
37775 login over SSH may be forbidden in some cases. To work around this,
37776 @command{guix deploy} can log in as an unprivileged user and employ
37777 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
37778 currently installed on the remote and can be invoked non-interactively as
37779 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
37780 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
37781 be accomplished with the following operating system configuration snippet:
37785 (gnu system)) ;for %sudoers-specification
37787 (define %user "username")
37792 (plain-file "sudoers"
37793 (string-append (plain-file-content %sudoers-specification)
37794 (format #f "~a ALL = NOPASSWD: ALL~%"
37799 For more information regarding the format of the @file{sudoers} file,
37800 consult @command{man sudoers}.
37802 Once you've deployed a system on a set of machines, you may find it
37803 useful to run a command on all of them. The @option{--execute} or
37804 @option{-x} option lets you do that; the example below runs
37805 @command{uname -a} on all the machines listed in the deployment file:
37808 guix deploy @var{file} -x -- uname -a
37811 One thing you may often need to do after deployment is restart specific
37812 services on all the machines, which you can do like so:
37815 guix deploy @var{file} -x -- herd restart @var{service}
37818 The @command{guix deploy -x} command returns zero if and only if the
37819 command succeeded on all the machines.
37821 @c FIXME/TODO: Separate the API doc from the CLI doc.
37823 Below are the data types you need to know about when writing a
37826 @deftp {Data Type} machine
37827 This is the data type representing a single machine in a heterogeneous Guix
37831 @item @code{operating-system}
37832 The object of the operating system configuration to deploy.
37834 @item @code{environment}
37835 An @code{environment-type} describing how the machine should be provisioned.
37837 @item @code{configuration} (default: @code{#f})
37838 An object describing the configuration for the machine's @code{environment}.
37839 If the @code{environment} has a default configuration, @code{#f} may be used.
37840 If @code{#f} is used for an environment with no default configuration,
37841 however, an error will be thrown.
37845 @deftp {Data Type} machine-ssh-configuration
37846 This is the data type representing the SSH client parameters for a machine
37847 with an @code{environment} of @code{managed-host-environment-type}.
37850 @item @code{host-name}
37851 @item @code{build-locally?} (default: @code{#t})
37852 If false, system derivations will be built on the machine being deployed to.
37853 @item @code{system}
37854 The system type describing the architecture of the machine being deployed
37855 to---e.g., @code{"x86_64-linux"}.
37856 @item @code{authorize?} (default: @code{#t})
37857 If true, the coordinator's signing key will be added to the remote's ACL
37859 @item @code{port} (default: @code{22})
37860 @item @code{user} (default: @code{"root"})
37861 @item @code{identity} (default: @code{#f})
37862 If specified, the path to the SSH private key to use to authenticate with the
37865 @item @code{host-key} (default: @code{#f})
37866 This should be the SSH host key of the machine, which looks like this:
37869 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
37872 When @code{host-key} is @code{#f}, the server is authenticated against
37873 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
37876 @item @code{allow-downgrades?} (default: @code{#f})
37877 Whether to allow potential downgrades.
37879 Like @command{guix system reconfigure}, @command{guix deploy} compares
37880 the channel commits currently deployed on the remote host (as returned
37881 by @command{guix system describe}) to those currently in use (as
37882 returned by @command{guix describe}) to determine whether commits
37883 currently in use are descendants of those deployed. When this is not
37884 the case and @code{allow-downgrades?} is false, it raises an error.
37885 This ensures you do not accidentally downgrade remote machines.
37887 @item @code{safety-checks?} (default: @code{#t})
37888 Whether to perform ``safety checks'' before deployment. This includes
37889 verifying that devices and file systems referred to in the operating
37890 system configuration actually exist on the target machine, and making
37891 sure that Linux modules required to access storage devices at boot time
37892 are listed in the @code{initrd-modules} field of the operating system.
37894 These safety checks ensure that you do not inadvertently deploy a system
37895 that would fail to boot. Be careful before turning them off!
37899 @deftp {Data Type} digital-ocean-configuration
37900 This is the data type describing the Droplet that should be created for a
37901 machine with an @code{environment} of @code{digital-ocean-environment-type}.
37904 @item @code{ssh-key}
37905 The path to the SSH private key to use to authenticate with the remote
37906 host. In the future, this field may not exist.
37908 A list of string ``tags'' that uniquely identify the machine. Must be given
37909 such that no two machines in the deployment have the same set of tags.
37910 @item @code{region}
37911 A Digital Ocean region slug, such as @code{"nyc3"}.
37913 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
37914 @item @code{enable-ipv6?}
37915 Whether or not the droplet should be created with IPv6 networking.
37919 @node Running Guix in a VM
37920 @section Running Guix in a Virtual Machine
37922 @cindex virtual machine
37923 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM
37924 image distributed at
37925 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.qcow2}.
37926 This image is a compressed image in QCOW format. You can pass it to an
37927 emulator such as @uref{https://qemu.org/, QEMU} (see below for details).
37929 This image boots the Xfce graphical environment and it contains some
37930 commonly used tools. You can install more software in the image by running
37931 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
37932 also reconfigure the system based on its initial configuration file available
37933 as @file{/run/current-system/configuration.scm} (@pxref{Using the
37934 Configuration System}).
37936 Instead of using this pre-built image, one can also build their own
37937 image using @command{guix system image} (@pxref{Invoking guix system}).
37940 If you built your own image, you must copy it out of the store
37941 (@pxref{The Store}) and give yourself permission to write to the copy
37942 before you can use it. When invoking QEMU, you must choose a system
37943 emulator that is suitable for your hardware platform. Here is a minimal
37944 QEMU invocation that will boot the result of @command{guix system
37945 image -t qcow2} on x86_64 hardware:
37948 $ qemu-system-x86_64 \
37949 -nic user,model=virtio-net-pci \
37950 -enable-kvm -m 1024 \
37951 -device virtio-blk,drive=myhd \
37952 -drive if=none,file=/tmp/qemu-image,id=myhd
37955 Here is what each of these options means:
37958 @item qemu-system-x86_64
37959 This specifies the hardware platform to emulate. This should match the
37962 @item -nic user,model=virtio-net-pci
37963 Enable the unprivileged user-mode network stack. The guest OS can
37964 access the host but not vice versa. This is the simplest way to get the
37965 guest OS online. @code{model} specifies which network device to emulate:
37966 @code{virtio-net-pci} is a special device made for virtualized operating
37967 systems and recommended for most uses. Assuming your hardware platform is
37968 x86_64, you can get a list of available NIC models by running
37969 @command{qemu-system-x86_64 -nic model=help}.
37972 If your system has hardware virtualization extensions, enabling the
37973 virtual machine support (KVM) of the Linux kernel will make things run
37976 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
37978 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
37979 which may be insufficient for some operations.
37981 @item -device virtio-blk,drive=myhd
37982 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
37983 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
37984 better performance than if it were emulating a complete disk drive. See the
37985 QEMU and KVM documentation for more info.
37987 @item -drive if=none,file=/tmp/qemu-image,id=myhd
37988 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
37989 store of the ``myhd'' drive.
37992 The default @command{run-vm.sh} script that is returned by an invocation of
37993 @command{guix system vm} does not add a @command{-nic user} flag by default.
37994 To get network access from within the vm add the @code{(dhcp-client-service)}
37995 to your system definition and start the VM using
37996 @command{$(guix system vm config.scm) -nic user}. An important caveat of using
37997 @command{-nic user} for networking is that @command{ping} will not work, because
37998 it uses the ICMP protocol. You'll have to use a different command to check for
37999 network connectivity, for example @command{guix download}.
38001 @subsection Connecting Through SSH
38005 To enable SSH inside a VM you need to add an SSH server like
38006 @code{openssh-service-type} to your VM (@pxref{Networking Services,
38007 @code{openssh-service-type}}). In addition you need to forward the SSH port,
38008 22 by default, to the host. You can do this with
38011 $(guix system vm config.scm) -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
38014 To connect to the VM you can run
38017 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022 localhost
38020 The @command{-p} tells @command{ssh} the port you want to connect to.
38021 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
38022 every time you modify your @command{config.scm} file and the
38023 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
38024 connection to an unknown host every time you connect.
38027 If you find the above @samp{hostfwd} example not to be working (e.g.,
38028 your SSH client hangs attempting to connect to the mapped port of your
38029 VM), make sure that your Guix System VM has networking support, such as
38030 by using the @code{dhcp-client-service-type} service type.
38033 @subsection Using @command{virt-viewer} with Spice
38035 As an alternative to the default @command{qemu} graphical client you can
38036 use the @command{remote-viewer} from the @command{virt-viewer} package. To
38037 connect pass the @command{-spice port=5930,disable-ticketing} flag to
38038 @command{qemu}. See previous section for further information on how to do this.
38040 Spice also allows you to do some nice stuff like share your clipboard with your
38041 VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
38044 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
38045 -chardev spicevmc,name=vdagent,id=vdagent
38046 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,\
38047 name=com.redhat.spice.0
38050 You'll also need to add the @code{(spice-vdagent-service)} to your
38051 system definition (@pxref{Miscellaneous Services, Spice service}).
38053 @node Defining Services
38054 @section Defining Services
38056 The previous sections show the available services and how one can combine
38057 them in an @code{operating-system} declaration. But how do we define
38058 them in the first place? And what is a service anyway?
38061 * Service Composition:: The model for composing services.
38062 * Service Types and Services:: Types and services.
38063 * Service Reference:: API reference.
38064 * Shepherd Services:: A particular type of service.
38065 * Complex Configurations:: Defining bindings for complex configurations.
38068 @node Service Composition
38069 @subsection Service Composition
38073 Here we define a @dfn{service} as, broadly, something that extends the
38074 functionality of the operating system. Often a service is a process---a
38075 @dfn{daemon}---started when the system boots: a secure shell server, a
38076 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
38077 whose execution can be triggered by another daemon---e.g., an FTP server
38078 started by @command{inetd} or a D-Bus service activated by
38079 @command{dbus-daemon}. Occasionally, a service does not map to a
38080 daemon. For instance, the ``account'' service collects user accounts
38081 and makes sure they exist when the system runs; the ``udev'' service
38082 collects device management rules and makes them available to the eudev
38083 daemon; the @file{/etc} service populates the @file{/etc} directory
38086 @cindex service extensions
38087 Guix system services are connected by @dfn{extensions}. For instance, the
38088 secure shell service @emph{extends} the Shepherd---the
38089 initialization system, running as PID@tie{}1---by giving it the command
38090 lines to start and stop the secure shell daemon (@pxref{Networking
38091 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
38092 service by passing it its @file{.service} specification, and extends the
38093 udev service by passing it device management rules (@pxref{Desktop
38094 Services, @code{upower-service}}); the Guix daemon service extends the
38095 Shepherd by passing it the command lines to start and stop the daemon,
38096 and extends the account service by passing it a list of required build
38097 user accounts (@pxref{Base Services}).
38099 All in all, services and their ``extends'' relations form a directed
38100 acyclic graph (DAG). If we represent services as boxes and extensions
38101 as arrows, a typical system might provide something like this:
38103 @image{images/service-graph,,5in,Typical service extension graph.}
38105 @cindex system service
38106 At the bottom, we see the @dfn{system service}, which produces the
38107 directory containing everything to run and boot the system, as returned
38108 by the @command{guix system build} command. @xref{Service Reference},
38109 to learn about the other service types shown here.
38110 @xref{system-extension-graph, the @command{guix system extension-graph}
38111 command}, for information on how to generate this representation for a
38112 particular operating system definition.
38114 @cindex service types
38115 Technically, developers can define @dfn{service types} to express these
38116 relations. There can be any number of services of a given type on the
38117 system---for instance, a system running two instances of the GNU secure
38118 shell server (lsh) has two instances of @code{lsh-service-type}, with
38119 different parameters.
38121 The following section describes the programming interface for service
38122 types and services.
38124 @node Service Types and Services
38125 @subsection Service Types and Services
38127 A @dfn{service type} is a node in the DAG described above. Let us start
38128 with a simple example, the service type for the Guix build daemon
38129 (@pxref{Invoking guix-daemon}):
38132 (define guix-service-type
38136 (list (service-extension shepherd-root-service-type guix-shepherd-service)
38137 (service-extension account-service-type guix-accounts)
38138 (service-extension activation-service-type guix-activation)))
38139 (default-value (guix-configuration))))
38143 It defines three things:
38147 A name, whose sole purpose is to make inspection and debugging easier.
38150 A list of @dfn{service extensions}, where each extension designates the
38151 target service type and a procedure that, given the parameters of the
38152 service, returns a list of objects to extend the service of that type.
38154 Every service type has at least one service extension. The only
38155 exception is the @dfn{boot service type}, which is the ultimate service.
38158 Optionally, a default value for instances of this type.
38161 In this example, @code{guix-service-type} extends three services:
38164 @item shepherd-root-service-type
38165 The @code{guix-shepherd-service} procedure defines how the Shepherd
38166 service is extended. Namely, it returns a @code{<shepherd-service>}
38167 object that defines how @command{guix-daemon} is started and stopped
38168 (@pxref{Shepherd Services}).
38170 @item account-service-type
38171 This extension for this service is computed by @code{guix-accounts},
38172 which returns a list of @code{user-group} and @code{user-account}
38173 objects representing the build user accounts (@pxref{Invoking
38176 @item activation-service-type
38177 Here @code{guix-activation} is a procedure that returns a gexp, which is
38178 a code snippet to run at ``activation time''---e.g., when the service is
38182 A service of this type is instantiated like this:
38185 (service guix-service-type
38186 (guix-configuration
38188 (extra-options '("--gc-keep-derivations"))))
38191 The second argument to the @code{service} form is a value representing
38192 the parameters of this specific service instance.
38193 @xref{guix-configuration-type, @code{guix-configuration}}, for
38194 information about the @code{guix-configuration} data type. When the
38195 value is omitted, the default value specified by
38196 @code{guix-service-type} is used:
38199 (service guix-service-type)
38202 @code{guix-service-type} is quite simple because it extends other
38203 services but is not extensible itself.
38205 @c @subsubsubsection Extensible Service Types
38207 The service type for an @emph{extensible} service looks like this:
38210 (define udev-service-type
38211 (service-type (name 'udev)
38213 (list (service-extension shepherd-root-service-type
38214 udev-shepherd-service)))
38216 (compose concatenate) ;concatenate the list of rules
38217 (extend (lambda (config rules)
38219 (($ <udev-configuration> udev initial-rules)
38220 (udev-configuration
38221 (udev udev) ;the udev package to use
38222 (rules (append initial-rules rules)))))))))
38225 This is the service type for the
38226 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
38227 management daemon}. Compared to the previous example, in addition to an
38228 extension of @code{shepherd-root-service-type}, we see two new fields:
38232 This is the procedure to @dfn{compose} the list of extensions to
38233 services of this type.
38235 Services can extend the udev service by passing it lists of rules; we
38236 compose those extensions simply by concatenating them.
38239 This procedure defines how the value of the service is @dfn{extended} with
38240 the composition of the extensions.
38242 Udev extensions are composed into a list of rules, but the udev service
38243 value is itself a @code{<udev-configuration>} record. So here, we
38244 extend that record by appending the list of rules it contains to the
38245 list of contributed rules.
38248 This is a string giving an overview of the service type. The string can
38249 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
38250 @command{guix system search} command searches these strings and displays
38251 them (@pxref{Invoking guix system}).
38254 There can be only one instance of an extensible service type such as
38255 @code{udev-service-type}. If there were more, the
38256 @code{service-extension} specifications would be ambiguous.
38258 Still here? The next section provides a reference of the programming
38259 interface for services.
38261 @node Service Reference
38262 @subsection Service Reference
38264 We have seen an overview of service types (@pxref{Service Types and
38265 Services}). This section provides a reference on how to manipulate
38266 services and service types. This interface is provided by the
38267 @code{(gnu services)} module.
38269 @deffn {Scheme Procedure} service @var{type} [@var{value}]
38270 Return a new service of @var{type}, a @code{<service-type>} object (see
38271 below). @var{value} can be any object; it represents the parameters of
38272 this particular service instance.
38274 When @var{value} is omitted, the default value specified by @var{type}
38275 is used; if @var{type} does not specify a default value, an error is
38278 For instance, this:
38281 (service openssh-service-type)
38285 is equivalent to this:
38288 (service openssh-service-type
38289 (openssh-configuration))
38292 In both cases the result is an instance of @code{openssh-service-type}
38293 with the default configuration.
38296 @deffn {Scheme Procedure} service? @var{obj}
38297 Return true if @var{obj} is a service.
38300 @deffn {Scheme Procedure} service-kind @var{service}
38301 Return the type of @var{service}---i.e., a @code{<service-type>} object.
38304 @deffn {Scheme Procedure} service-value @var{service}
38305 Return the value associated with @var{service}. It represents its
38309 Here is an example of how a service is created and manipulated:
38313 (service nginx-service-type
38314 (nginx-configuration
38316 (log-directory log-directory)
38317 (run-directory run-directory)
38318 (file config-file))))
38323 (eq? (service-kind s) nginx-service-type)
38327 The @code{modify-services} form provides a handy way to change the
38328 parameters of some of the services of a list such as
38329 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
38330 evaluates to a list of services. Of course, you could always use
38331 standard list combinators such as @code{map} and @code{fold} to do that
38332 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
38333 @code{modify-services} simply provides a more concise form for this
38336 @deffn {Scheme Syntax} modify-services @var{services} @
38337 (@var{type} @var{variable} => @var{body}) @dots{}
38339 Modify the services listed in @var{services} according to the given
38340 clauses. Each clause has the form:
38343 (@var{type} @var{variable} => @var{body})
38346 where @var{type} is a service type---e.g.,
38347 @code{guix-service-type}---and @var{variable} is an identifier that is
38348 bound within the @var{body} to the service parameters---e.g., a
38349 @code{guix-configuration} instance---of the original service of that
38352 The @var{body} should evaluate to the new service parameters, which will
38353 be used to configure the new service. This new service will replace the
38354 original in the resulting list. Because a service's service parameters
38355 are created using @code{define-record-type*}, you can write a succinct
38356 @var{body} that evaluates to the new service parameters by using the
38357 @code{inherit} feature that @code{define-record-type*} provides.
38359 Clauses can also have the following form:
38362 (delete @var{type})
38365 Such a clause removes all services of the given @var{type} from
38368 @xref{Using the Configuration System}, for example usage.
38372 Next comes the programming interface for service types. This is
38373 something you want to know when writing new service definitions, but not
38374 necessarily when simply looking for ways to customize your
38375 @code{operating-system} declaration.
38377 @deftp {Data Type} service-type
38378 @cindex service type
38379 This is the representation of a @dfn{service type} (@pxref{Service Types
38384 This is a symbol, used only to simplify inspection and debugging.
38386 @item @code{extensions}
38387 A non-empty list of @code{<service-extension>} objects (see below).
38389 @item @code{compose} (default: @code{#f})
38390 If this is @code{#f}, then the service type denotes services that cannot
38391 be extended---i.e., services that do not receive ``values'' from other
38394 Otherwise, it must be a one-argument procedure. The procedure is called
38395 by @code{fold-services} and is passed a list of values collected from
38396 extensions. It may return any single value.
38398 @item @code{extend} (default: @code{#f})
38399 If this is @code{#f}, services of this type cannot be extended.
38401 Otherwise, it must be a two-argument procedure: @code{fold-services}
38402 calls it, passing it the initial value of the service as the first
38403 argument and the result of applying @code{compose} to the extension
38404 values as the second argument. It must return a value that is a valid
38405 parameter value for the service instance.
38407 @item @code{description}
38408 This is a string, possibly using Texinfo markup, describing in a couple
38409 of sentences what the service is about. This string allows users to
38410 find about the service through @command{guix system search}
38411 (@pxref{Invoking guix system}).
38413 @item @code{default-value} (default: @code{&no-default-value})
38414 The default value associated for instances of this service type. This
38415 allows users to use the @code{service} form without its second argument:
38418 (service @var{type})
38421 The returned service in this case has the default value specified by
38425 @xref{Service Types and Services}, for examples.
38428 @deffn {Scheme Procedure} service-extension @var{target-type} @
38430 Return a new extension for services of type @var{target-type}.
38431 @var{compute} must be a one-argument procedure: @code{fold-services}
38432 calls it, passing it the value associated with the service that provides
38433 the extension; it must return a valid value for the target service.
38436 @deffn {Scheme Procedure} service-extension? @var{obj}
38437 Return true if @var{obj} is a service extension.
38440 Occasionally, you might want to simply extend an existing service. This
38441 involves creating a new service type and specifying the extension of
38442 interest, which can be verbose; the @code{simple-service} procedure
38443 provides a shorthand for this.
38445 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
38446 Return a service that extends @var{target} with @var{value}. This works
38447 by creating a singleton service type @var{name}, of which the returned
38448 service is an instance.
38450 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
38454 (simple-service 'my-mcron-job mcron-service-type
38455 #~(job '(next-hour (3)) "guix gc -F 2G"))
38459 At the core of the service abstraction lies the @code{fold-services}
38460 procedure, which is responsible for ``compiling'' a list of services
38461 down to a single directory that contains everything needed to boot and
38462 run the system---the directory shown by the @command{guix system build}
38463 command (@pxref{Invoking guix system}). In essence, it propagates
38464 service extensions down the service graph, updating each node parameters
38465 on the way, until it reaches the root node.
38467 @deffn {Scheme Procedure} fold-services @var{services} @
38468 [#:target-type @var{system-service-type}]
38469 Fold @var{services} by propagating their extensions down to the root of
38470 type @var{target-type}; return the root service adjusted accordingly.
38473 Lastly, the @code{(gnu services)} module also defines several essential
38474 service types, some of which are listed below.
38476 @defvr {Scheme Variable} system-service-type
38477 This is the root of the service graph. It produces the system directory
38478 as returned by the @command{guix system build} command.
38481 @defvr {Scheme Variable} boot-service-type
38482 The type of the ``boot service'', which produces the @dfn{boot script}.
38483 The boot script is what the initial RAM disk runs when booting.
38486 @defvr {Scheme Variable} etc-service-type
38487 The type of the @file{/etc} service. This service is used to create
38488 files under @file{/etc} and can be extended by
38489 passing it name/file tuples such as:
38492 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
38495 In this example, the effect would be to add an @file{/etc/issue} file
38496 pointing to the given file.
38499 @defvr {Scheme Variable} setuid-program-service-type
38500 Type for the ``setuid-program service''. This service collects lists of
38501 executable file names, passed as gexps, and adds them to the set of
38502 setuid and setgid programs on the system (@pxref{Setuid Programs}).
38505 @defvr {Scheme Variable} profile-service-type
38506 Type of the service that populates the @dfn{system profile}---i.e., the
38507 programs under @file{/run/current-system/profile}. Other services can
38508 extend it by passing it lists of packages to add to the system profile.
38511 @cindex provenance tracking, of the operating system
38512 @anchor{provenance-service-type}
38513 @defvr {Scheme Variable} provenance-service-type
38514 This is the type of the service that records @dfn{provenance meta-data}
38515 in the system itself. It creates several files under
38516 @file{/run/current-system}:
38520 This is a ``channel file'' that can be passed to @command{guix pull -C}
38521 or @command{guix time-machine -C}, and which describes the channels used
38522 to build the system, if that information was available
38523 (@pxref{Channels}).
38525 @item configuration.scm
38526 This is the file that was passed as the value for this
38527 @code{provenance-service-type} service. By default, @command{guix
38528 system reconfigure} automatically passes the OS configuration file it
38529 received on the command line.
38532 This contains the same information as the two other files but in a
38533 format that is more readily processable.
38536 In general, these two pieces of information (channels and configuration
38537 file) are enough to reproduce the operating system ``from source''.
38540 This information is necessary to rebuild your operating system, but it
38541 is not always sufficient. In particular, @file{configuration.scm}
38542 itself is insufficient if it is not self-contained---if it refers to
38543 external Guile modules or to extra files. If you want
38544 @file{configuration.scm} to be self-contained, we recommend that modules
38545 or files it refers to be part of a channel.
38547 Besides, provenance meta-data is ``silent'' in the sense that it does
38548 not change the bits contained in your system, @emph{except for the
38549 meta-data bits themselves}. Two different OS configurations or sets of
38550 channels can lead to the same system, bit-for-bit; when
38551 @code{provenance-service-type} is used, these two systems will have
38552 different meta-data and thus different store file names, which makes
38553 comparison less trivial.
38556 This service is automatically added to your operating system
38557 configuration when you use @command{guix system reconfigure},
38558 @command{guix system init}, or @command{guix deploy}.
38561 @defvr {Scheme Variable} linux-loadable-module-service-type
38562 Type of the service that collects lists of packages containing
38563 kernel-loadable modules, and adds them to the set of kernel-loadable
38566 This service type is intended to be extended by other service types,
38570 (simple-service 'installing-module
38571 linux-loadable-module-service-type
38572 (list module-to-install-1
38573 module-to-install-2))
38576 This does not actually load modules at bootup, only adds it to the
38577 kernel profile so that it @emph{can} be loaded by other means.
38580 @node Shepherd Services
38581 @subsection Shepherd Services
38583 @cindex shepherd services
38585 @cindex init system
38586 The @code{(gnu services shepherd)} module provides a way to define
38587 services managed by the GNU@tie{}Shepherd, which is the
38588 initialization system---the first process that is started when the
38589 system boots, also known as PID@tie{}1
38590 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
38592 Services in the Shepherd can depend on each other. For instance, the
38593 SSH daemon may need to be started after the syslog daemon has been
38594 started, which in turn can only happen once all the file systems have
38595 been mounted. The simple operating system defined earlier (@pxref{Using
38596 the Configuration System}) results in a service graph like this:
38598 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
38600 You can actually generate such a graph for any operating system
38601 definition using the @command{guix system shepherd-graph} command
38602 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
38604 The @code{%shepherd-root-service} is a service object representing
38605 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
38606 by passing it lists of @code{<shepherd-service>} objects.
38608 @deftp {Data Type} shepherd-service
38609 The data type representing a service managed by the Shepherd.
38612 @item @code{provision}
38613 This is a list of symbols denoting what the service provides.
38615 These are the names that may be passed to @command{herd start},
38616 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
38617 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
38618 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
38620 @item @code{requirement} (default: @code{'()})
38621 List of symbols denoting the Shepherd services this one depends on.
38623 @cindex one-shot services, for the Shepherd
38624 @item @code{one-shot?} (default: @code{#f})
38625 Whether this service is @dfn{one-shot}. One-shot services stop immediately
38626 after their @code{start} action has completed. @xref{Slots of services,,,
38627 shepherd, The GNU Shepherd Manual}, for more info.
38629 @item @code{respawn?} (default: @code{#t})
38630 Whether to restart the service when it stops, for instance when the
38631 underlying process dies.
38634 @itemx @code{stop} (default: @code{#~(const #f)})
38635 The @code{start} and @code{stop} fields refer to the Shepherd's
38636 facilities to start and stop processes (@pxref{Service De- and
38637 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
38638 G-expressions that get expanded in the Shepherd configuration file
38639 (@pxref{G-Expressions}).
38641 @item @code{actions} (default: @code{'()})
38642 @cindex actions, of Shepherd services
38643 This is a list of @code{shepherd-action} objects (see below) defining
38644 @dfn{actions} supported by the service, in addition to the standard
38645 @code{start} and @code{stop} actions. Actions listed here become available as
38646 @command{herd} sub-commands:
38649 herd @var{action} @var{service} [@var{arguments}@dots{}]
38652 @item @code{auto-start?} (default: @code{#t})
38653 Whether this service should be started automatically by the Shepherd. If it
38654 is @code{#f} the service has to be started manually with @code{herd start}.
38656 @item @code{documentation}
38657 A documentation string, as shown when running:
38660 herd doc @var{service-name}
38663 where @var{service-name} is one of the symbols in @code{provision}
38664 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
38666 @item @code{modules} (default: @code{%default-modules})
38667 This is the list of modules that must be in scope when @code{start} and
38668 @code{stop} are evaluated.
38673 The example below defines a Shepherd service that spawns
38674 @command{syslogd}, the system logger from the GNU Networking Utilities
38675 (@pxref{syslogd invocation, @command{syslogd},, inetutils, GNU
38679 (let ((config (plain-file "syslogd.conf" "@dots{}")))
38681 (documentation "Run the syslog daemon (syslogd).")
38682 (provision '(syslogd))
38683 (requirement '(user-processes))
38684 (start #~(make-forkexec-constructor
38685 (list #$(file-append inetutils "/libexec/syslogd")
38686 "--rcfile" #$config)
38687 #:pid-file "/var/run/syslog.pid"))
38688 (stop #~(make-kill-destructor))))
38691 Key elements in this example are the @code{start} and @code{stop}
38692 fields: they are @dfn{staged} code snippets that use the
38693 @code{make-forkexec-constructor} procedure provided by the Shepherd and
38694 its dual, @code{make-kill-destructor} (@pxref{Service De- and
38695 Constructors,,, shepherd, The GNU Shepherd Manual}). The @code{start}
38696 field will have @command{shepherd} spawn @command{syslogd} with the
38697 given option; note that we pass @code{config} after @option{--rcfile},
38698 which is a configuration file declared above (contents of this file are
38699 omitted). Likewise, the @code{stop} field tells how this service is to
38700 be stopped; in this case, it is stopped by making the @code{kill} system
38701 call on its PID@. Code staging is achieved using G-expressions:
38702 @code{#~} stages code, while @code{#$} ``escapes'' back to host code
38703 (@pxref{G-Expressions}).
38705 @deftp {Data Type} shepherd-action
38706 This is the data type that defines additional actions implemented by a
38707 Shepherd service (see above).
38711 Symbol naming the action.
38713 @item documentation
38714 This is a documentation string for the action. It can be viewed by running:
38717 herd doc @var{service} action @var{action}
38721 This should be a gexp that evaluates to a procedure of at least one argument,
38722 which is the ``running value'' of the service (@pxref{Slots of services,,,
38723 shepherd, The GNU Shepherd Manual}).
38726 The following example defines an action called @code{say-hello} that kindly
38732 (documentation "Say hi!")
38733 (procedure #~(lambda (running . args)
38734 (format #t "Hello, friend! arguments: ~s\n"
38739 Assuming this action is added to the @code{example} service, then you can do:
38742 # herd say-hello example
38743 Hello, friend! arguments: ()
38744 # herd say-hello example a b c
38745 Hello, friend! arguments: ("a" "b" "c")
38748 This, as you can see, is a fairly sophisticated way to say hello.
38749 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
38753 @defvr {Scheme Variable} shepherd-root-service-type
38754 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
38756 This is the service type that extensions target when they want to create
38757 shepherd services (@pxref{Service Types and Services}, for an example).
38758 Each extension must pass a list of @code{<shepherd-service>}. Its
38759 value must be a @code{shepherd-configuration}, as described below.
38762 @deftp {Data Type} shepherd-configuration
38763 This data type represents the Shepherd's configuration.
38766 @item shepherd (default: @code{shepherd})
38767 The Shepherd package to use.
38769 @item services (default: @code{'()})
38770 A list of @code{<shepherd-service>} to start.
38771 You should probably use the service extension
38772 mechanism instead (@pxref{Shepherd Services}).
38776 The following example specifies the Shepherd package for the operating
38782 (services (append (list openssh-service-type))
38786 ;; Use own Shepherd package.
38787 (essential-services
38788 (modify-services (operating-system-default-essential-services
38789 this-operating-system)
38790 (shepherd-root-service-type config => (shepherd-configuration
38792 (shepherd my-shepherd))))))
38795 @defvr {Scheme Variable} %shepherd-root-service
38796 This service represents PID@tie{}1.
38799 @node Complex Configurations
38800 @subsection Complex Configurations
38801 @cindex complex configurations
38802 Some programs might have rather complex configuration files or formats,
38803 and to make it easier to create Scheme bindings for these configuration
38804 files, you can use the utilities defined in the @code{(gnu services
38805 configuration)} module.
38807 The main utility is the @code{define-configuration} macro, which you
38808 will use to define a Scheme record type (@pxref{Record Overview,,,
38809 guile, GNU Guile Reference Manual}). The Scheme record will be
38810 serialized to a configuration file by using @dfn{serializers}, which are
38811 procedures that take some kind of Scheme value and returns a
38812 G-expression (@pxref{G-Expressions}), which should, once serialized to
38813 the disk, return a string. More details are listed below.
38815 @deffn {Scheme Syntax} define-configuration @var{name} @var{clause1} @
38817 Create a record type named @code{@var{name}} that contains the
38818 fields found in the clauses.
38820 A clause can have one of the following forms:
38824 (@var{type} @var{default-value})
38825 @var{documentation})
38828 (@var{type} @var{default-value})
38829 @var{documentation}
38834 @var{documentation})
38838 @var{documentation}
38842 @var{field-name} is an identifier that denotes the name of the field in
38843 the generated record.
38845 @var{type} is the type of the value corresponding to @var{field-name};
38846 since Guile is untyped, a predicate
38847 procedure---@code{@var{type}?}---will be called on the value
38848 corresponding to the field to ensure that the value is of the correct
38849 type. This means that if say, @var{type} is @code{package}, then a
38850 procedure named @code{package?} will be applied on the value to make
38851 sure that it is indeed a @code{<package>} object.
38853 @var{default-value} is the default value corresponding to the field; if
38854 none is specified, the user is forced to provide a value when creating
38855 an object of the record type.
38857 @c XXX: Should these be full sentences or are they allow to be very
38858 @c short like package synopses?
38859 @var{documentation} is a string formatted with Texinfo syntax which
38860 should provide a description of what setting this field does.
38862 @var{serializer} is the name of a procedure which takes two arguments,
38863 the first is the name of the field, and the second is the value
38864 corresponding to the field. The procedure should return a string or
38865 G-expression (@pxref{G-Expressions}) that represents the content that
38866 will be serialized to the configuration file. If none is specified, a
38867 procedure of the name @code{serialize-@var{type}} will be used.
38869 A simple serializer procedure could look like this:
38872 (define (serialize-boolean field-name value)
38873 (let ((value (if value "true" "false")))
38874 #~(string-append #$field-name #$value)))
38877 In some cases multiple different configuration records might be defined
38878 in the same file, but their serializers for the same type might have to
38879 be different, because they have different configuration formats. For
38880 example, the @code{serialize-boolean} procedure for the Getmail service
38881 would have to be different for the one for the Transmission service. To
38882 make it easier to deal with this situation, one can specify a serializer
38883 prefix by using the @code{prefix} literal in the
38884 @code{define-configuration} form. This means that one doesn't have to
38885 manually specify a custom @var{serializer} for every field.
38888 (define (foo-serialize-string field-name value)
38891 (define (bar-serialize-string field-name value)
38894 (define-configuration foo-configuration
38897 "The name of label.")
38900 (define-configuration bar-configuration
38903 "The IPv4 address for this device.")
38907 However, in some cases you might not want to serialize any of the values
38908 of the record, to do this, you can use the @code{no-serialization}
38909 literal. There is also the @code{define-configuration/no-serialization}
38910 macro which is a shorthand of this.
38913 ;; Nothing will be serialized to disk.
38914 (define-configuration foo-configuration
38917 "Some documentation.")
38918 (no-serialization))
38920 ;; The same thing as above.
38921 (define-configuration/no-serialization bar-configuration
38924 "Some documentation."))
38928 @deffn {Scheme Syntax} define-maybe @var{type}
38929 Sometimes a field should not be serialized if the user doesn’t specify a
38930 value. To achieve this, you can use the @code{define-maybe} macro to
38931 define a ``maybe type''; if the value of a maybe type is left unset, or
38932 is set to the @code{'unset} value, then it will not be
38935 When defining a ``maybe type'', the corresponding serializer for the
38936 regular type will be used by default. For example, a field of type
38937 @code{maybe-string} will be serialized using the @code{serialize-string}
38938 procedure by default, you can of course change this by specifying a
38939 custom serializer procedure. Likewise, the type of the value would have
38940 to be a string, or left unspecified.
38943 (define-maybe string)
38945 (define (serialize-string field-name value)
38948 (define-configuration baz-configuration
38950 ;; If set to a string, the `serialize-string' procedure will be used
38951 ;; to serialize the string. Otherwise this field is not serialized.
38952 maybe-string ; equivalent to (maybe-string *unspecified*)
38953 "The name of this module."))
38956 Like with @code{define-configuration}, one can set a prefix for the
38957 serializer name by using the @code{prefix} literal.
38960 (define-maybe integer
38963 (define (baz-serialize-interger field-name value)
38967 There is also the @code{no-serialization} literal, which when set means
38968 that no serializer will be defined for the ``maybe type'', regardless of
38969 whether its value is set or not.
38970 @code{define-maybe/no-serialization} is a shorthand for specifying the
38971 @code{no-serialization} literal.
38974 (define-maybe/no-serialization symbol)
38976 (define-configuration/no-serialization test-configuration
38983 @deffn {Scheme Procedure} serialize-configuration @var{configuration} @
38985 Return a G-expression that contains the values corresponding to the
38986 @var{fields} of @var{configuration}, a record that has been generated by
38987 @code{define-configuration}. The G-expression can then be serialized to
38988 disk by using something like @code{mixed-text-file}.
38991 @deffn {Scheme Procedure} empty-serializer @var{field-name} @var{value}
38992 A serializer that just returns an empty string. The
38993 @code{serialize-package} procedure is an alias for this.
38996 Once you have defined a configuration record, you will most likely also
38997 want to document it so that other people know to use it. To help with
38998 that, there are two procedures, both of which are documented below.
39000 @deffn {Scheme Procedure} generate-documentation @var{documentation} @
39001 @var{documentation-name}
39002 Generate a Texinfo fragment from the docstrings in @var{documentation},
39003 a list of @code{(@var{label} @var{fields} @var{sub-documentation} ...)}.
39004 @var{label} should be a symbol and should be the name of the
39005 configuration record. @var{fields} should be a list of all the fields
39006 available for the configuration record.
39008 @var{sub-documentation} is a @code{(@var{field-name}
39009 @var{configuration-name})} tuple. @var{field-name} is the name of the
39010 field which takes another configuration record as its value, and
39011 @var{configuration-name} is the name of that configuration record.
39013 @var{sub-documentation} is only needed if there are nested configuration
39014 records. For example, the @code{getmail-configuration} record
39015 (@pxref{Mail Services}) accepts a @code{getmail-configuration-file}
39016 record in one of its @code{rcfile} field, therefore documentation for
39017 @code{getmail-configuration-file} is nested in
39018 @code{getmail-configuration}.
39021 (generate-documentation
39022 `((getmail-configuration ,getmail-configuration-fields
39023 (rcfile getmail-configuration-file))
39025 'getmail-configuration)
39028 @var{documentation-name} should be a symbol and should be the name of
39029 the configuration record.
39033 @deffn {Scheme Procedure} configuration->documentation
39034 @var{configuration-symbol}
39035 Take @var{configuration-symbol}, the symbol corresponding to the name
39036 used when defining a configuration record with
39037 @code{define-configuration}, and print the Texinfo documentation of its
39038 fields. This is useful if there aren’t any nested configuration records
39039 since it only prints the documentation for the top-level fields.
39042 As of right now, there is no automated way to generate documentation for
39043 configuration records and put them in the manual. Instead, every
39044 time you make a change to the docstrings of a configuration record, you
39045 have to manually call @code{generate-documentation} or
39046 @code{configuration->documentation}, and paste the output into the
39047 @file{doc/guix.texi} file.
39049 @c TODO: Actually test this
39050 Below is an example of a record type created using
39051 @code{define-configuration} and friends.
39054 (use-modules (gnu services)
39056 (gnu services configuration)
39060 ;; Turn field names, which are Scheme symbols into strings
39061 (define (uglify-field-name field-name)
39062 (let ((str (symbol->string field-name)))
39063 ;; field? -> is-field
39064 (if (string-suffix? "?" str)
39065 (string-append "is-" (string-drop-right str 1))
39068 (define (serialize-string field-name value)
39069 #~(string-append #$(uglify-field-name field-name) " = " #$value "\n"))
39071 (define (serialize-integer field-name value)
39072 (serialize-string field-name (number->string value)))
39074 (define (serialize-boolean field-name value)
39075 (serialize-string field-name (if value "true" "false")))
39077 (define (serialize-contact-name field-name value)
39078 #~(string-append "\n[" #$value "]\n"))
39080 (define (list-of-contact-configurations? lst)
39081 (every contact-configuration? lst))
39083 (define (serialize-list-of-contact-configurations field-name value)
39084 #~(string-append #$@@(map (cut serialize-configuration <>
39085 contact-configuration-fields)
39088 (define (serialize-contacts-list-configuration configuration)
39091 #~(string-append "[Owner]\n"
39092 #$(serialize-configuration
39093 configuration contacts-list-configuration-fields))))
39095 (define-maybe integer)
39096 (define-maybe string)
39098 (define-configuration contact-configuration
39101 "The name of the contact."
39102 serialize-contact-name)
39105 "The person's phone number.")
39108 "The person's email address.")
39111 "Whether the person is married."))
39113 (define-configuration contacts-list-configuration
39116 "The name of the owner of this contact list.")
39119 "The owner's email address.")
39121 (list-of-contact-configurations '())
39122 "A list of @@code@{contact-configuation@} records which contain
39123 information about all your contacts."))
39126 A contacts list configuration could then be created like this:
39129 (define my-contacts
39130 (contacts-list-configuration
39132 (email "alice@@example.org")
39134 (list (contact-configuration
39136 (phone-number 1234)
39137 (email "bob@@gnu.org")
39139 (contact-configuration
39141 (phone-number 0000)
39145 After serializing the configuration to disk, the resulting file would
39151 email = alice@@example.org
39154 phone-number = 1234
39155 email = bob@@gnu.org
39164 @node Home Configuration
39165 @chapter Home Configuration
39166 @cindex home configuration
39167 Guix supports declarative configuration of @dfn{home environments} by
39168 utilizing the configuration mechanism described in the previous chapter
39169 (@pxref{Defining Services}), but for user's dotfiles and packages. It
39170 works both on Guix System and foreign distros and allows users to
39171 declare all the packages and services that should be installed and
39172 configured for the user. Once a user has written a file containing
39173 @code{home-environment} record, such a configuration can be
39174 @dfn{instantiated} by an unprivileged user with the @command{guix home}
39175 command (@pxref{Invoking guix home}).
39176 @c Maybe later, it will be possible to make home configuration a part of
39177 @c system configuration to make everything managed by guix system.
39180 The functionality described in this section is still under development
39181 and is subject to change. Get in touch with us on
39182 @email{guix-devel@@gnu.org}!
39185 The user's home environment usually consists of three basic parts:
39186 software, configuration, and state. Software in mainstream distros are
39187 usually installed system-wide, but with GNU Guix most software packages
39188 can be installed on a per-user basis without needing root privileges,
39189 and are thus considered part of the user’s @dfn{home environment}.
39190 Packages on their own not very useful in many cases, because often they
39191 require some additional configuration, usually config files that reside
39192 in @env{XDG_CONFIG_HOME} (@file{~/.config} by default) or other
39193 directories. Everything else can be considered state, like media files,
39194 application databases, and logs.
39196 Using Guix for managing home environments provides a number of
39201 @item All software can be configured in one language (Guile Scheme),
39202 this gives users the ability to share values between configurations of
39203 different programs.
39205 @item A well-defined home environment is self-contained and can be
39206 created in a declarative and reproducible way---there is no need to grab
39207 external binaries or manually edit some configuration file.
39209 @item After every @command{guix home reconfigure} invocation, a new home
39210 environment generation will be created. This means that users can
39211 rollback to a previous home environment generation so they don’t have to
39212 worry about breaking their configuration.
39214 @item It is possible to manage stateful data with Guix Home, this
39215 includes the ability to automatically clone Git repositories on the
39216 initial setup of the machine, and periodically running commands like
39217 @command{rsync} to sync data with another host. This functionality is
39218 still in an experimental stage, though.
39223 * Declaring the Home Environment:: Customizing your Home.
39224 * Configuring the Shell:: Enabling home environment.
39225 * Home Services:: Specifying home services.
39226 * Invoking guix home:: Instantiating a home configuration.
39229 @node Declaring the Home Environment
39230 @section Declaring the Home Environment
39231 The home environment is configured by providing a
39232 @code{home-environment} declaration in a file that can be passed to the
39233 @command{guix home} command (@pxref{Invoking guix home}). The easiest
39234 way to get started is by generating an initial configuration with
39235 @command{guix home import}:
39238 guix home import ~/src/guix-config
39241 The @command{guix home import} command reads some of the ``dot files''
39242 such as @file{~/.bashrc} found in your home directory and copies them to
39243 the given directory, @file{~/src/guix-config} in this case; it also
39244 reads the contents of your profile, @file{~/.guix-profile}, and, based
39245 on that, it populates @file{~/src/guix-config/home-configuration.scm}
39246 with a Home configuration that resembles your current configuration.
39248 A simple setup can include Bash and a custom text configuration, like in
39249 the example below. Don't be afraid to declare home environment parts,
39250 which overlaps with your current dot files: before installing any
39251 configuration files, Guix Home will back up existing config files to a
39252 separate place in the home directory.
39255 It is highly recommended that you manage your shell or shells with Guix
39256 Home, because it will make sure that all the necessary scripts are
39257 sourced by the shell configuration file. Otherwise you will need to do
39258 it manually. (@pxref{Configuring the Shell}).
39261 @findex home-environment
39263 @include he-config-bare-bones.scm
39266 The @code{packages} field should be self-explanatory, it will install
39267 the list of packages into the user's profile. The most important field
39268 is @code{services}, it contains a list of @dfn{home services}, which are
39269 the basic building blocks of a home environment.
39271 There is no daemon (at least not necessarily) related to a home service,
39272 a home service is just an element that is used to declare part of home
39273 environment and extend other parts of it. The extension mechanism
39274 discussed in the previous chapter (@pxref{Defining Services}) should not
39275 be confused with Shepherd services (@pxref{Shepherd Services}). Using this extension
39276 mechanism and some Scheme code that glues things together gives the user
39277 the freedom to declare their own, very custom, home environments.
39279 @cindex container, for @command{guix home}
39280 Once the configuration looks good, you can first test it in a throw-away
39284 guix home container config.scm
39287 The command above spawns a shell where your home environment is running.
39288 The shell runs in a container, meaning it's isolated from the rest of
39289 the system, so it's a good way to try out your configuration---you can
39290 see if configuration bits are missing or misbehaving, if daemons get
39291 started, and so on. Once you exit that shell, you're back to the prompt
39292 of your original shell ``in the real world''.
39294 Once you have a configuration file that suits your needs, you can
39295 reconfigure your home by running:
39298 guix home reconfigure config.scm
39301 This ``builds'' your home environment and creates @file{~/.guix-home}
39302 pointing to it. Voilà!
39305 Make sure the operating system has elogind, systemd, or a similar
39306 mechanism to create the XDG run-time directory and has the
39307 @env{XDG_RUNTIME_DIR} variable set. Failing that, the
39308 @file{on-first-login} script will not execute anything, and processes
39309 like user Shepherd and its descendants will not start.
39312 @node Configuring the Shell
39313 @section Configuring the Shell
39314 This section is safe to skip if your shell or shells are managed by
39315 Guix Home. Otherwise, read it carefully.
39317 There are a few scripts that must be evaluated by a login shell to
39318 activate the home environment. The shell startup files only read by
39319 login shells often have @code{profile} suffix. For more information
39320 about login shells see @ref{Invoking Bash,,, bash, The GNU Bash
39321 Reference Manual} and see @ref{Bash Startup Files,,, bash, The GNU Bash
39324 The first script that needs to be sourced is @file{setup-environment},
39325 which sets all the necessary environment variables (including variables
39326 declared by the user) and the second one is @file{on-first-login}, which
39327 starts Shepherd for the current user and performs actions declared by
39328 other home services that extends
39329 @code{home-run-on-first-login-service-type}.
39331 Guix Home will always create @file{~/.profile}, which contains the
39335 HOME_ENVIRONMENT=$HOME/.guix-home
39336 . $HOME_ENVIRONMENT/setup-environment
39337 $HOME_ENVIRONMENT/on-first-login
39340 This makes POSIX compliant login shells activate the home environment.
39341 However, in most cases this file won't be read by most modern shells,
39342 because they are run in non POSIX mode by default and have their own
39343 @file{*profile} startup files. For example Bash will prefer
39344 @file{~/.bash_profile} in case it exists and only if it doesn't will it
39345 fallback to @file{~/.profile}. Zsh (if no additional options are
39346 specified) will ignore @file{~/.profile}, even if @file{~/.zprofile}
39349 To make your shell respect @file{~/.profile}, add @code{. ~/.profile} or
39350 @code{source ~/profile} to the startup file for the login shell. In
39351 case of Bash, it is @file{~/.bash_profile}, and in case of Zsh, it is
39352 @file{~/.zprofile}.
39355 This step is only required if your shell is NOT managed by Guix Home.
39356 Otherwise, everything will be done automatically.
39359 @node Home Services
39360 @section Home Services
39361 @cindex home services
39363 A @dfn{home service} is not necessarily something that has a daemon and
39364 is managed by Shepherd (@pxref{Jump Start,,, shepherd, The GNU Shepherd
39365 Manual}), in most cases it doesn't. It's a simple building block of the
39366 home environment, often declaring a set of packages to be installed in
39367 the home environment profile, a set of config files to be symlinked into
39368 @env{XDG_CONFIG_HOME} (@file{~/.config} by default), and environment
39369 variables to be set by a login shell.
39371 There is a service extension mechanism (@pxref{Service Composition})
39372 which allows home services to extend other home services and utilize
39373 capabilities they provide; for example: declare mcron jobs
39374 (@pxref{Top,,, mcron, GNU@tie{}Mcron}) by extending @ref{Mcron Home
39375 Service}; declare daemons by extending @ref{Shepherd Home Service}; add
39376 commands, which will be invoked on by the Bash by extending
39377 @ref{Shells Home Services, @code{home-bash-service-type}}.
39379 A good way to discover available home services is using the
39380 @command{guix home search} command (@pxref{Invoking guix home}). After
39381 the required home services are found, include its module with the
39382 @code{use-modules} form (@pxref{use-modules,, Using Guile Modules,
39383 guile, The GNU Guile Reference Manual}), or the @code{#:use-modules}
39384 directive (@pxref{define-module,, Creating Guile Modules, guile, The GNU
39385 Guile Reference Manual}) and declare a home service using the
39386 @code{service} function, or extend a service type by declaring a new
39387 service with the @code{simple-service} procedure from @code{(gnu
39391 * Essential Home Services:: Environment variables, packages, on-* scripts.
39392 * Shells: Shells Home Services. POSIX shells, Bash, Zsh.
39393 * Mcron: Mcron Home Service. Scheduled User's Job Execution.
39394 * Shepherd: Shepherd Home Service. Managing User's Daemons.
39395 * SSH: Secure Shell. Setting up the secure shell client.
39396 * Desktop: Desktop Home Services. Services for graphical environments.
39397 * Guix: Guix Home Services. Services for Guix.
39399 @c In addition to that Home Services can provide
39401 @node Essential Home Services
39402 @subsection Essential Home Services
39403 There are a few essential home services defined in
39404 @code{(gnu services)}, they are mostly for internal use and are required
39405 to build a home environment, but some of them will be useful for the end
39408 @cindex environment variables
39410 @defvr {Scheme Variable} home-environment-variables-service-type
39411 The service of this type will be instantiated by every home environment
39412 automatically by default, there is no need to define it, but someone may
39413 want to extend it with a list of pairs to set some environment
39417 (list ("ENV_VAR1" . "value1")
39418 ("ENV_VAR2" . "value2"))
39421 The easiest way to extend a service type, without defining a new service
39422 type is to use the @code{simple-service} helper from @code{(gnu
39426 (simple-service 'some-useful-env-vars-service
39427 home-environment-variables-service-type
39428 `(("LESSHISTFILE" . "$XDG_CACHE_HOME/.lesshst")
39429 ("SHELL" . ,(file-append zsh "/bin/zsh"))
39430 ("USELESS_VAR" . #f)
39431 ("_JAVA_AWT_WM_NONREPARENTING" . #t)))
39434 If you include such a service in you home environment definition, it
39435 will add the following content to the @file{setup-environment} script
39436 (which is expected to be sourced by the login shell):
39439 export LESSHISTFILE=$XDG_CACHE_HOME/.lesshst
39440 export SHELL=/gnu/store/2hsg15n644f0glrcbkb1kqknmmqdar03-zsh-5.8/bin/zsh
39441 export _JAVA_AWT_WM_NONREPARENTING
39445 Make sure that module @code{(gnu packages shells)} is imported with
39446 @code{use-modules} or any other way, this namespace contains the
39447 definition of the @code{zsh} packages, which is used in the example
39451 The association list (@pxref{Association Lists, alists, Association
39452 Lists, guile, The GNU Guile Reference manual}) is a data structure
39453 containing key-value pairs, for
39454 @code{home-environment-variables-service-type} the key is always a
39455 string, the value can be a string, string-valued gexp
39456 (@pxref{G-Expressions}), file-like object (@pxref{G-Expressions,
39457 file-like object}) or boolean. For gexps, the variable will be set to
39458 the value of the gexp; for file-like objects, it will be set to the path
39459 of the file in the store (@pxref{The Store}); for @code{#t}, it will
39460 export the variable without any value; and for @code{#f}, it will omit
39465 @defvr {Scheme Variable} home-profile-service-type
39466 The service of this type will be instantiated by every home environment
39467 automatically, there is no need to define it, but you may want to extend
39468 it with a list of packages if you want to install additional packages
39469 into your profile. Other services, which need to make some programs
39470 available to the user will also extend this service type.
39472 The extension value is just a list of packages:
39475 (list htop vim emacs)
39478 The same approach as @code{simple-service} (@pxref{Service Reference,
39479 simple-service}) for @code{home-environment-variables-service-type} can
39480 be used here, too. Make sure that modules containing the specified
39481 packages are imported with @code{use-modules}. To find a package or
39482 information about its module use @command{guix search} (@pxref{Invoking
39483 guix package}). Alternatively, @code{specification->package} can be
39484 used to get the package record from string without importing related
39488 There are few more essential services, but users are not expected to
39491 @defvr {Scheme Variable} home-service-type
39492 The root of home services DAG, it generates a folder, which later will be
39493 symlinked to @file{~/.guix-home}, it contains configurations,
39494 profile with binaries and libraries, and some necessary scripts to glue
39498 @defvr {Scheme Variable} home-run-on-first-login-service-type
39499 The service of this type generates a Guile script, which is expected to
39500 be executed by the login shell. It is only executed if the special flag
39501 file inside @env{XDG_RUNTIME_DIR} hasn't been created, this prevents
39502 redundant executions of the script if multiple login shells are spawned.
39504 It can be extended with a gexp. However, to autostart an application,
39505 users @emph{should not} use this service, in most cases it's better to extend
39506 @code{home-shepherd-service-type} with a Shepherd service
39507 (@pxref{Shepherd Services}), or extend the shell's startup file with
39508 the required command using the appropriate service type.
39511 @defvr {Scheme Variable} home-activation-service-type
39512 The service of this type generates a guile script, which runs on every
39513 @command{guix home reconfigure} invocation or any other action, which
39514 leads to the activation of the home environment.
39517 @node Shells Home Services
39521 @cindex login shell
39522 @cindex interactive shell
39526 Shells play a quite important role in the environment initialization
39527 process, you can configure them manually as described in section
39528 @ref{Configuring the Shell}, but the recommended way is to use home services
39529 listed below. It's both easier and more reliable.
39531 Each home environment instantiates
39532 @code{home-shell-profile-service-type}, which creates a
39533 @file{~/.profile} startup file for all POSIX-compatible shells. This
39534 file contains all the necessary steps to properly initialize the
39535 environment, but many modern shells like Bash or Zsh prefer their own
39536 startup files, that's why the respective home services
39537 (@code{home-bash-service-type} and @code{home-zsh-service-type}) ensure
39538 that @file{~/.profile} is sourced by @file{~/.bash_profile} and
39539 @file{~/.zprofile}, respectively.
39541 @subsubheading Shell Profile Service
39543 @deftp {Data Type} home-shell-profile-configuration
39544 Available @code{home-shell-profile-configuration} fields are:
39547 @item @code{profile} (default: @code{()}) (type: text-config)
39548 @code{home-shell-profile} is instantiated automatically by
39549 @code{home-environment}, DO NOT create this service manually, it can
39550 only be extended. @code{profile} is a list of file-like objects, which
39551 will go to @file{~/.profile}. By default @file{~/.profile} contains the
39552 initialization code which must be evaluated by the login shell to make
39553 home-environment's profile available to the user, but other commands can
39554 be added to the file if it is really necessary. In most cases shell's
39555 configuration files are preferred places for user's customizations.
39556 Extend home-shell-profile service only if you really know what you do.
39562 @subsubheading Bash Home Service
39564 @anchor{home-bash-configuration}
39565 @deftp {Data Type} home-bash-configuration
39566 Available @code{home-bash-configuration} fields are:
39569 @item @code{package} (default: @code{bash}) (type: package)
39570 The Bash package to use.
39572 @item @code{guix-defaults?} (default: @code{#t}) (type: boolean)
39573 Add sane defaults like reading @file{/etc/bashrc} and coloring the output of
39574 @command{ls} to the top of the @file{.bashrc} file.
39576 @item @code{environment-variables} (default: @code{()}) (type: alist)
39577 Association list of environment variables to set for the Bash session. The
39578 rules for the @code{home-environment-variables-service-type} apply
39579 here (@pxref{Essential Home Services}). The contents of this field will be
39580 added after the contents of the @code{bash-profile} field.
39582 @item @code{aliases} (default: @code{()}) (type: alist)
39583 Association list of aliases to set for the Bash session. The aliases
39584 will be defined after the contents of the @code{bashrc} field has been
39585 put in the @file{.bashrc} file. The alias will automatically be quoted,
39586 so something line this:
39589 '(("ls" . "ls -alF"))
39598 @item @code{bash-profile} (default: @code{()}) (type: text-config)
39599 List of file-like objects, which will be added to @file{.bash_profile}.
39600 Used for executing user's commands at start of login shell (In most
39601 cases the shell started on tty just after login). @file{.bash_login}
39602 won't be ever read, because @file{.bash_profile} always present.
39604 @item @code{bashrc} (default: @code{()}) (type: text-config)
39605 List of file-like objects, which will be added to @file{.bashrc}. Used
39606 for executing user's commands at start of interactive shell (The shell
39607 for interactive usage started by typing @code{bash} or by terminal app
39608 or any other program).
39610 @item @code{bash-logout} (default: @code{()}) (type: text-config)
39611 List of file-like objects, which will be added to @file{.bash_logout}.
39612 Used for executing user's commands at the exit of login shell. It won't
39613 be read in some cases (if the shell terminates by exec'ing another
39614 process for example).
39619 You can extend the Bash service by using the @code{home-bash-extension}
39620 configuration record, whose fields most mirror that of
39621 @code{home-bash-configuration} (@pxref{home-bash-configuration}). The
39622 contents of the extensions will be added to the end of the corresponding
39623 Bash configuration files (@pxref{Bash Startup Files,,, bash, The GNU
39624 Bash Reference Manual}.
39626 For example, here is how you would define a service that extends the
39627 Bash service such that @file{~/.bash_profile} defines an additional
39628 environment variable, @env{PS1}:
39631 (define bash-fancy-prompt-service
39632 (simple-service 'bash-fancy-prompt
39633 home-bash-service-type
39634 (home-bash-extension
39635 (environment-variables
39636 '(("PS1" . "\\u \\wλ "))))))
39639 You would then add @code{bash-fancy-prompt-service} to the list in the
39640 @code{services} field of your @code{home-environment}. The reference of
39641 @code{home-bash-extension} follows.
39643 @deftp {Data Type} home-bash-extension
39644 Available @code{home-bash-extension} fields are:
39647 @item @code{environment-variables} (default: @code{()}) (type: alist)
39648 Additional environment variables to set. These will be combined with the
39649 environment variables from other extensions and the base service to form one
39650 coherent block of environment variables.
39652 @item @code{aliases} (default: @code{()}) (type: alist)
39653 Additional aliases to set. These will be combined with the aliases from
39654 other extensions and the base service.
39656 @item @code{bash-profile} (default: @code{()}) (type: text-config)
39657 Additional text blocks to add to @file{.bash_profile}, which will be combined
39658 with text blocks from other extensions and the base service.
39660 @item @code{bashrc} (default: @code{()}) (type: text-config)
39661 Additional text blocks to add to @file{.bashrc}, which will be combined
39662 with text blocks from other extensions and the base service.
39664 @item @code{bash-logout} (default: @code{()}) (type: text-config)
39665 Additional text blocks to add to @file{.bash_logout}, which will be combined
39666 with text blocks from other extensions and the base service.
39671 @subsubheading Zsh Home Service
39673 @deftp {Data Type} home-zsh-configuration
39674 Available @code{home-zsh-configuration} fields are:
39677 @item @code{package} (default: @code{zsh}) (type: package)
39678 The Zsh package to use.
39680 @item @code{xdg-flavor?} (default: @code{#t}) (type: boolean)
39681 Place all the configs to @file{$XDG_CONFIG_HOME/zsh}. Makes
39682 @file{~/.zshenv} to set @env{ZDOTDIR} to @file{$XDG_CONFIG_HOME/zsh}.
39683 Shell startup process will continue with
39684 @file{$XDG_CONFIG_HOME/zsh/.zshenv}.
39686 @item @code{environment-variables} (default: @code{()}) (type: alist)
39687 Association list of environment variables to set for the Zsh session.
39689 @item @code{zshenv} (default: @code{()}) (type: text-config)
39690 List of file-like objects, which will be added to @file{.zshenv}. Used
39691 for setting user's shell environment variables. Must not contain
39692 commands assuming the presence of tty or producing output. Will be read
39693 always. Will be read before any other file in @env{ZDOTDIR}.
39695 @item @code{zprofile} (default: @code{()}) (type: text-config)
39696 List of file-like objects, which will be added to @file{.zprofile}. Used
39697 for executing user's commands at start of login shell (In most cases the
39698 shell started on tty just after login). Will be read before
39701 @item @code{zshrc} (default: @code{()}) (type: text-config)
39702 List of file-like objects, which will be added to @file{.zshrc}. Used
39703 for executing user's commands at start of interactive shell (The shell
39704 for interactive usage started by typing @code{zsh} or by terminal app or
39705 any other program).
39707 @item @code{zlogin} (default: @code{()}) (type: text-config)
39708 List of file-like objects, which will be added to @file{.zlogin}. Used
39709 for executing user's commands at the end of starting process of login
39712 @item @code{zlogout} (default: @code{()}) (type: text-config)
39713 List of file-like objects, which will be added to @file{.zlogout}. Used
39714 for executing user's commands at the exit of login shell. It won't be
39715 read in some cases (if the shell terminates by exec'ing another process
39722 @node Mcron Home Service
39723 @subsection Scheduled User's Job Execution
39727 @cindex scheduling jobs
39729 The @code{(gnu home services mcron)} module provides an interface to
39730 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
39731 mcron, GNU@tie{}mcron}). The information about system's mcron is
39732 applicable here (@pxref{Scheduled Job Execution}), the only difference
39733 for home services is that they have to be declared in a
39734 @code{home-environment} record instead of an @code{operating-system}
39737 @defvr {Scheme Variable} home-mcron-service-type
39738 This is the type of the @code{mcron} home service, whose value is an
39739 @code{home-mcron-configuration} object. It allows to manage scheduled
39742 This service type can be the target of a service extension that provides
39743 additional job specifications (@pxref{Service Composition}). In other
39744 words, it is possible to define services that provide additional mcron
39748 @deftp {Data Type} home-mcron-configuration
39749 Data type representing the configuration of mcron.
39752 @item @code{mcron} (default: @var{mcron})
39753 The mcron package to use.
39756 This is a list of gexps (@pxref{G-Expressions}), where each gexp
39757 corresponds to an mcron job specification (@pxref{Syntax, mcron job
39758 specifications,, mcron, GNU@tie{}mcron}).
39762 @node Shepherd Home Service
39763 @subsection Managing User Daemons
39765 @cindex shepherd services, for users
39766 The @code{(gnu home services shepherd)} module supports the definitions
39767 of per-user Shepherd services (@pxref{Introduction,,, shepherd, The GNU
39768 Shepherd Manual}). You extend @code{home-shepherd-service-type} with
39769 new services; Guix Home then takes care of starting the @code{shepherd}
39770 daemon for you when you log in, which in turns starts the services you
39773 @defvr {Scheme Variable} home-shepherd-service-type
39774 The service type for the userland Shepherd, which allows one to manage
39775 long-running processes or one-shot tasks. User's Shepherd is not an
39776 init process (PID 1), but almost all other information described in
39777 (@pxref{Shepherd Services}) is applicable here too.
39779 This is the service type that extensions target when they want to create
39780 shepherd services (@pxref{Service Types and Services}, for an example).
39781 Each extension must pass a list of @code{<shepherd-service>}. Its
39782 value must be a @code{home-shepherd-configuration}, as described below.
39785 @deftp {Data Type} home-shepherd-configuration
39786 This data type represents the Shepherd's configuration.
39789 @item shepherd (default: @code{shepherd})
39790 The Shepherd package to use.
39792 @item auto-start? (default: @code{#t})
39793 Whether or not to start Shepherd on first login.
39795 @item services (default: @code{'()})
39796 A list of @code{<shepherd-service>} to start.
39797 You should probably use the service extension
39798 mechanism instead (@pxref{Shepherd Services}).
39803 @subsection Secure Shell
39805 @cindex secure shell client, configuration
39806 @cindex SSH client, configuration
39807 The @uref{https://www.openssh.com, OpenSSH package} includes a client,
39808 the @command{ssh} command, that allows you to connect to remote machines
39809 using the @acronym{SSH, secure shell} protocol. With the @code{(gnu
39810 home services ssh)} module, you can set up OpenSSH so that it works in a
39811 predictable fashion, almost independently of state on the local machine.
39812 To do that, you instantiate @code{home-openssh-service-type} in your
39813 Home configuration, as explained below.
39815 @defvr {Scheme Variable} home-openssh-service-type
39816 This is the type of the service to set up the OpenSSH client. It takes
39817 care of several things:
39821 providing a @file{~/.ssh/config} file based on your configuration so
39822 that @command{ssh} knows about hosts you regularly connect to and their
39823 associated parameters;
39826 providing a @file{~/.ssh/authorized_keys}, which lists public keys that
39827 the local SSH server, @command{sshd}, may accept to connect to this user
39831 optionally providing a @file{~/.ssh/known_hosts} file so that @file{ssh}
39832 can authenticate hosts you connect to.
39835 Here is an example of a service and its configuration that you could add
39836 to the @code{services} field of your @code{home-environment}:
39839 (service home-openssh-service-type
39840 (home-openssh-configuration
39842 (list (openssh-host (name "ci.guix.gnu.org")
39844 (openssh-host (name "chbouib")
39845 (host-name "chbouib.example.org")
39846 (user "supercharlie")
39848 (authorized-keys (list (local-file "alice.pub")))))
39851 The example above lists two hosts and their parameters. For instance,
39852 running @command{ssh chbouib} will automatically connect to
39853 @code{chbouib.example.org} on port 10022, logging in as user
39854 @samp{supercharlie}. Further, it marks the public key in
39855 @file{alice.pub} as authorized for incoming connections.
39857 The value associated with a @code{home-openssh-service-type} instance
39858 must be a @code{home-openssh-configuration} record, as describe below.
39861 @deftp {Data Type} home-openssh-configuration
39862 This is the datatype representing the OpenSSH client and server
39863 configuration in one's home environment. It contains the following
39867 @item @code{hosts} (default: @code{'()})
39868 A list of @code{openssh-host} records specifying host names and
39869 associated connection parameters (see below). This host list goes into
39870 @file{~/.ssh/config}, which @command{ssh} reads at startup.
39872 @item @code{known-hosts} (default: @code{*unspecified*})
39873 This must be either:
39877 @code{*unspecified*}, in which case @code{home-openssh-service-type}
39878 leaves it up to @command{ssh} and to the user to maintain the list of
39879 known hosts at @file{~/.ssh/known_hosts}, or
39882 a list of file-like objects, in which case those are concatenated and
39883 emitted as @file{~/.ssh/known_hosts}.
39886 The @file{~/.ssh/known_hosts} contains a list of host name/host key
39887 pairs that allow @command{ssh} to authenticate hosts you connect to and
39888 to detect possible impersonation attacks. By default, @command{ssh}
39889 updates it in a @dfn{TOFU, trust-on-first-use} fashion, meaning that it
39890 records the host's key in that file the first time you connect to it.
39891 This behavior is preserved when @code{known-hosts} is set to
39892 @code{*unspecified*}.
39894 If you instead provide a list of host keys upfront in the
39895 @code{known-hosts} field, your configuration becomes self-contained and
39896 stateless: it can be replicated elsewhere or at another point in time.
39897 Preparing this list can be relatively tedious though, which is why
39898 @code{*unspecified*} is kept as a default.
39900 @item @code{authorized-keys} (default: @code{'()})
39901 This must be a list of file-like objects, each of which containing an
39902 SSH public key that should be authorized to connect to this machine.
39904 Concretely, these files are concatenated and made available as
39905 @file{~/.ssh/authorized_keys}. If an OpenSSH server, @command{sshd}, is
39906 running on this machine, then it @emph{may} take this file into account:
39907 this is what @command{sshd} does by default, but be aware that it can
39908 also be configured to ignore it.
39912 @c %start of fragment
39914 @deftp {Data Type} openssh-host
39915 Available @code{openssh-host} fields are:
39918 @item @code{name} (type: string)
39919 Name of this host declaration.
39921 @item @code{host-name} (type: maybe-string)
39922 Host name---e.g., @code{"foo.example.org"} or @code{"192.168.1.2"}.
39924 @item @code{address-family} (type: address-family)
39925 Address family to use when connecting to this host: one of
39926 @code{AF_INET} (for IPv4 only), @code{AF_INET6} (for IPv6 only), or
39927 @code{*unspecified*} (allowing any address family).
39929 @item @code{identity-file} (type: maybe-string)
39930 The identity file to use---e.g., @code{"/home/charlie/.ssh/id_ed25519"}.
39932 @item @code{port} (type: maybe-natural-number)
39933 TCP port number to connect to.
39935 @item @code{user} (type: maybe-string)
39936 User name on the remote host.
39938 @item @code{forward-x11?} (default: @code{#f}) (type: boolean)
39939 Whether to forward remote client connections to the local X11 graphical
39942 @item @code{forward-x11-trusted?} (default: @code{#f}) (type: boolean)
39943 Whether remote X11 clients have full access to the original X11
39946 @item @code{forward-agent?} (default: @code{#f}) (type: boolean)
39947 Whether the authentication agent (if any) is forwarded to the remote
39950 @item @code{compression?} (default: @code{#f}) (type: boolean)
39951 Whether to compress data in transit.
39953 @item @code{proxy-command} (type: maybe-string)
39954 The command to use to connect to the server. As an example, a command
39955 to connect via an HTTP proxy at 192.0.2.0 would be: @code{"nc -X connect
39956 -x 192.0.2.0:8080 %h %p"}.
39958 @item @code{host-key-algorithms} (type: maybe-string-list)
39959 The list of accepted host key algorithms---e.g.,
39960 @code{'("ssh-ed25519")}.
39962 @item @code{accepted-key-types} (type: maybe-string-list)
39963 The list of accepted user public key types.
39965 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
39966 Extra content appended as-is to this @code{Host} block in
39967 @file{~/.ssh/config}.
39974 @c %end of fragment
39977 @node Desktop Home Services
39978 @subsection Desktop Home Services
39980 The @code{(gnu home services desktop)} module provides services that you
39981 may find useful on ``desktop'' systems running a graphical user
39982 environment such as Xorg.
39984 @defvr {Scheme Variable} home-redshift-service-type
39985 This is the service type for @uref{https://github.com/jonls/redshift,
39986 Redshift}, a program that adjusts the display color temperature
39987 according to the time of day. Its associated value must be a
39988 @code{home-redshift-configuration} record, as shown below.
39990 A typical configuration, where we manually specify the latitude and
39991 longitude, might look like this:
39994 (service home-redshift-service-type
39995 (home-redshift-configuration
39996 (location-provider 'manual)
39997 (latitude 35.81) ;northern hemisphere
39998 (longitude -0.80))) ;west of Greenwich
40002 @deftp {Data Type} home-redshift-configuration
40003 Available @code{home-redshift-configuration} fields are:
40006 @item @code{redshift} (default: @code{redshift}) (type: file-like)
40007 Redshift package to use.
40009 @item @code{location-provider} (default: @code{geoclue2}) (type: symbol)
40010 Geolocation provider---@code{'manual} or @code{'geoclue2}. In the
40011 former case, you must also specify the @code{latitude} and
40012 @code{longitude} fields so Redshift can determine daytime at your place.
40013 In the latter case, the Geoclue system service must be running; it will
40014 be queried for location information.
40016 @item @code{adjustment-method} (default: @code{randr}) (type: symbol)
40017 Color adjustment method.
40019 @item @code{daytime-temperature} (default: @code{6500}) (type: integer)
40020 Daytime color temperature (kelvins).
40022 @item @code{nighttime-temperature} (default: @code{4500}) (type: integer)
40023 Nighttime color temperature (kelvins).
40025 @item @code{daytime-brightness} (type: maybe-inexact-number)
40026 Daytime screen brightness, between 0.1 and 1.0, or left unspecified.
40028 @item @code{nighttime-brightness} (type: maybe-inexact-number)
40029 Nighttime screen brightness, between 0.1 and 1.0, or left unspecified.
40031 @item @code{latitude} (type: maybe-inexact-number)
40032 Latitude, when @code{location-provider} is @code{'manual}.
40034 @item @code{longitude} (type: maybe-inexact-number)
40035 Longitude, when @code{location-provider} is @code{'manual}.
40037 @item @code{dawn-time} (type: maybe-string)
40038 Custom time for the transition from night to day in the
40039 morning---@code{"HH:MM"} format. When specified, solar elevation is not
40040 used to determine the daytime/nighttime period.
40042 @item @code{dusk-time} (type: maybe-string)
40043 Likewise, custom time for the transition from day to night in the
40046 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40047 Extra content appended as-is to the Redshift configuration file. Run
40048 @command{man redshift} for more information about the configuration file
40055 @node Guix Home Services
40056 @subsection Guix Home Services
40058 The @code{(gnu home services guix)} module provides services for
40059 user-specific Guix configuration.
40061 @defvr {Scheme Variable} home-channels-service-type
40062 This is the service type for managing
40063 @file{$XDG_CONFIG_HOME/guix/channels.scm}, the file that controls the
40064 channels received on @command{guix pull} (@pxref{Channels}). Its
40065 associated value is a list of @code{channel} records, defined in the
40066 @code{(guix channels)} module.
40068 Generally, it is better to extend this service than to directly
40069 configure it, as its default value is the default guix channel(s)
40070 defined by @code{%default-channels}. If you configure this service
40071 directly, be sure to include a guix channel. @xref{Specifying
40072 Additional Channels} and @ref{Using a Custom Guix Channel} for more
40075 A typical extension for adding a channel might look like this:
40078 (simple-service 'variant-packages-service
40079 home-channels-service-type
40082 (name 'variant-packages)
40083 (url "https://example.org/variant-packages.git")))
40087 @node Invoking guix home
40088 @section Invoking @code{guix home}
40090 Once you have written a home environment declaration (@pxref{Declaring
40091 the Home Environment,,,,}, it can be @dfn{instantiated} using the
40092 @command{guix home} command. The synopsis is:
40095 guix home @var{options}@dots{} @var{action} @var{file}
40098 @var{file} must be the name of a file containing a
40099 @code{home-environment} declaration. @var{action} specifies how the
40100 home environment is instantiated, but there are few auxiliary actions
40101 which don't instantiate it. Currently the following values are
40106 Display available home service type definitions that match the given
40107 regular expressions, sorted by relevance:
40110 @cindex shell-profile
40114 $ guix home search shell
40115 name: home-shell-profile
40116 location: gnu/home/services/shells.scm:100:2
40117 extends: home-files
40118 description: Create `~/.profile', which is used for environment initialization of POSIX compliant login shells.
40119 + This service type can be extended with a list of file-like objects.
40123 location: gnu/home/services/shells.scm:640:2
40124 extends: home-files home-profile
40125 description: Install and configure Fish, the friendly interactive shell.
40129 location: gnu/home/services/shells.scm:290:2
40130 extends: home-files home-profile
40131 description: Install and configure Zsh.
40135 location: gnu/home/services/shells.scm:508:2
40136 extends: home-files home-profile
40137 description: Install and configure GNU Bash.
40143 As for @command{guix search}, the result is written in
40144 @code{recutils} format, which makes it easy to filter the output
40145 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
40147 @cindex container, for @command{guix home}
40149 Spawn a shell in an isolated environment---a
40150 @dfn{container}---containing your home as specified by @var{file}.
40152 For example, this is how you would start an interactive shell in a
40153 container with your home:
40156 guix home container config.scm
40159 This is a throw-away container where you can lightheartedly fiddle with
40160 files; any changes made within the container, any process started---all
40161 this disappears as soon as you exit that shell.
40163 As with @command{guix shell}, several options control that container:
40168 Enable networking within the container (it is disabled by default).
40170 @item --expose=@var{source}[=@var{target}]
40171 @itemx --share=@var{source}[=@var{target}]
40172 As with @command{guix shell}, make directory @var{source} of the host
40173 system available as @var{target} inside the container---read-only if you
40174 pass @option{--expose}, and writable if you pass @option{--share}
40175 (@pxref{Invoking guix shell, @option{--expose} and @option{--share}}).
40178 Additionally, you can run a command in that container, instead of
40179 spawning an interactive shell. For instance, here is how you would
40180 check which Shepherd services are started in a throw-away home
40184 guix home container config.scm -- herd status
40187 The command to run in the container must come after @code{--} (double
40190 @cindex service type definition, editing
40191 @cindex editing, service type definition
40193 Edit or view the definition of the given Home service types.
40195 For example, the command below opens your editor, as specified by the
40196 @env{EDITOR} environment variable, on the definition of the
40197 @code{home-mcron} service type:
40200 guix home edit home-mcron
40204 Build the home environment described in @var{file}, and switch to it.
40205 Switching means that the activation script will be evaluated and (in
40206 basic scenario) symlinks to configuration files generated from
40207 @code{home-environment} declaration will be created in @file{~}. If the
40208 file with the same path already exists in home folder it will be moved
40209 to @file{~/@var{timestamp}-guix-home-legacy-configs-backup}, where @var{timestamp}
40210 is a current UNIX epoch time.
40213 It is highly recommended to run @command{guix pull} once before you run
40214 @command{guix home reconfigure} for the first time (@pxref{Invoking guix
40218 This effects all the configuration specified in @var{file}. The command
40219 starts Shepherd services specified in @var{file} that are not currently
40220 running; if a service is currently running, this command will arrange
40221 for it to be upgraded the next time it is stopped (e.g.@: by @code{herd
40222 stop @var{service}} or @code{herd restart @var{service}}).
40224 This command creates a new generation whose number is one greater than
40225 the current generation (as reported by @command{guix home
40226 list-generations}). If that generation already exists, it will be
40227 overwritten. This behavior mirrors that of @command{guix package}
40228 (@pxref{Invoking guix package}).
40230 @cindex provenance tracking, of the home environment
40231 Upon completion, the new home is deployed under @file{~/.guix-home}.
40232 This directory contains @dfn{provenance meta-data}: the list of channels
40233 in use (@pxref{Channels}) and @var{file} itself, when available. You
40234 can view the provenance information by running:
40240 This information is useful should you later want to inspect how this
40241 particular generation was built. In fact, assuming @var{file} is
40242 self-contained, you can later rebuild generation @var{n} of your
40243 home environment with:
40246 guix time-machine \
40247 -C /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/channels.scm -- \
40249 /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/configuration.scm
40253 You can think of it as some sort of built-in version control! Your
40254 home is not just a binary artifact: @emph{it carries its own source}.
40255 @c @xref{Service Reference, @code{provenance-service-type}}, for more
40256 @c information on provenance tracking.
40258 @c @footnote{This action (and the related actions
40259 @c @code{switch-generation} and @code{roll-back}) are usable after the
40260 @c home environment is initialized.}.
40262 @item switch-generation
40263 @cindex home generations
40264 Switch to an existing home generation. This action atomically switches
40265 the home profile to the specified home generation.
40267 The target generation can be specified explicitly by its generation
40268 number. For example, the following invocation would switch to home
40272 guix home switch-generation 7
40275 The target generation can also be specified relative to the current
40276 generation with the form @code{+N} or @code{-N}, where @code{+3} means
40277 ``3 generations ahead of the current generation,'' and @code{-1} means
40278 ``1 generation prior to the current generation.'' When specifying a
40279 negative value such as @code{-1}, you must precede it with @code{--} to
40280 prevent it from being parsed as an option. For example:
40283 guix home switch-generation -- -1
40286 This action will fail if the specified generation does not exist.
40289 @cindex rolling back
40290 Switch to the preceding home generation. This is the inverse
40291 of @command{reconfigure}, and it is exactly the same as invoking
40292 @command{switch-generation} with an argument of @code{-1}.
40294 @item delete-generations
40295 @cindex deleting home generations
40296 @cindex saving space
40297 Delete home generations, making them candidates for garbage collection
40298 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
40301 This works in the same way as @samp{guix package --delete-generations}
40302 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
40303 arguments, all home generations but the current one are deleted:
40306 guix home delete-generations
40309 You can also select the generations you want to delete. The example below
40310 deletes all the home generations that are more than two months old:
40313 guix home delete-generations 2m
40317 Build the derivation of the home environment, which includes all the
40318 configuration files and programs needed. This action does not actually
40322 Describe the current home generation: its file name, as well as
40323 provenance information when available.
40325 To show installed packages in the current home generation's profile, the
40326 @code{--list-installed} flag is provided, with the same syntax that is
40327 used in @command{guix package --list-installed} (@pxref{Invoking guix
40328 package}). For instance, the following command shows a table of all the
40329 packages with ``emacs'' in their name that are installed in the current
40330 home generation's profile:
40333 guix home describe --list-installed=emacs
40336 @item list-generations
40337 List a summary of each generation of the home environment available on
40338 disk, in a human-readable way. This is similar to the
40339 @option{--list-generations} option of @command{guix package}
40340 (@pxref{Invoking guix package}).
40342 Optionally, one can specify a pattern, with the same syntax that is used
40343 in @command{guix package --list-generations}, to restrict the list of
40344 generations displayed. For instance, the following command displays
40345 generations that are up to 10 days old:
40348 guix home list-generations 10d
40351 The @code{--list-installed} flag may also be specified, with the same
40352 syntax that is used in @command{guix home describe}. This may be
40353 helpful if trying to determine when a package was added to the home
40357 Generate a @dfn{home environment} from the packages in the default
40358 profile and configuration files found in the user's home directory. The
40359 configuration files will be copied to the specified directory, and a
40360 @file{home-configuration.scm} will be populated with the home
40361 environment. Note that not every home service that exists is supported
40362 (@pxref{Home Services}).
40365 $ guix home import ~/guix-config
40366 guix home: '/home/alice/guix-config' populated with all the Home configuration files
40370 And there's more! @command{guix home} also provides the following
40371 sub-commands to visualize how the services of your home environment
40372 relate to one another:
40375 @cindex service extension graph, of a home environment
40376 @item extension-graph
40377 Emit to standard output the @dfn{service extension graph} of the home
40378 environment defined in @var{file} (@pxref{Service Composition}, for more
40379 information on service extensions). By default the output is in
40380 Dot/Graphviz format, but you can choose a different format with
40381 @option{--graph-backend}, as with @command{guix graph} (@pxref{Invoking
40382 guix graph, @option{--backend}}):
40387 guix home extension-graph @var{file} | xdot -
40390 shows the extension relations among services.
40392 @cindex Shepherd dependency graph, for a home environment
40393 @item shepherd-graph
40394 Emit to standard output the @dfn{dependency graph} of shepherd services
40395 of the home environment defined in @var{file}. @xref{Shepherd
40396 Services}, for more information and for an example graph.
40398 Again, the default output format is Dot/Graphviz, but you can pass
40399 @option{--graph-backend} to select a different one.
40402 @var{options} can contain any of the common build options (@pxref{Common
40403 Build Options}). In addition, @var{options} can contain one of the
40408 @item --expression=@var{expr}
40409 @itemx -e @var{expr}
40410 Consider the home-environment @var{expr} evaluates to.
40411 This is an alternative to specifying a file which evaluates to a home
40414 @item --allow-downgrades
40415 Instruct @command{guix home reconfigure} to allow system downgrades.
40417 Just like @command{guix system}, @command{guix home reconfigure}, by
40418 default, prevents you from downgrading your home to older or unrelated
40419 revisions compared to the channel revisions that were used to deploy
40420 it---those shown by @command{guix home describe}. Using
40421 @option{--allow-downgrades} allows you to bypass that check, at the risk
40422 of downgrading your home---be careful!
40426 @node Documentation
40427 @chapter Documentation
40429 @cindex documentation, searching for
40430 @cindex searching for documentation
40431 @cindex Info, documentation format
40433 @cindex manual pages
40434 In most cases packages installed with Guix come with documentation.
40435 There are two main documentation formats: ``Info'', a browsable
40436 hypertext format used for GNU software, and ``manual pages'' (or ``man
40437 pages''), the linear documentation format traditionally found on Unix.
40438 Info manuals are accessed with the @command{info} command or with Emacs,
40439 and man pages are accessed using @command{man}.
40441 You can look for documentation of software installed on your system by
40442 keyword. For example, the following command searches for information
40443 about ``TLS'' in Info manuals:
40447 "(emacs)Network Security" -- STARTTLS
40448 "(emacs)Network Security" -- TLS
40449 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
40450 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
40455 The command below searches for the same keyword in man
40456 pages@footnote{The database searched by @command{man -k} is only created
40457 in profiles that contain the @code{man-db} package.}:
40461 SSL (7) - OpenSSL SSL/TLS library
40462 certtool (1) - GnuTLS certificate tool
40466 These searches are purely local to your computer so you have the
40467 guarantee that documentation you find corresponds to what you have
40468 actually installed, you can access it off-line, and your privacy is
40471 Once you have these results, you can view the relevant documentation by
40475 $ info "(gnutls)Core TLS API"
40485 Info manuals contain sections and indices as well as hyperlinks like
40486 those found in Web pages. The @command{info} reader (@pxref{Top, Info
40487 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
40488 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
40489 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
40490 Introduction}, for an introduction to Info navigation.
40492 @node Installing Debugging Files
40493 @chapter Installing Debugging Files
40495 @cindex debugging files
40496 Program binaries, as produced by the GCC compilers for instance, are
40497 typically written in the ELF format, with a section containing
40498 @dfn{debugging information}. Debugging information is what allows the
40499 debugger, GDB, to map binary code to source code; it is required to
40500 debug a compiled program in good conditions.
40502 This chapter explains how to use separate debug info when packages
40503 provide it, and how to rebuild packages with debug info when it's
40507 * Separate Debug Info:: Installing 'debug' outputs.
40508 * Rebuilding Debug Info:: Building missing debug info.
40511 @node Separate Debug Info
40512 @section Separate Debug Info
40514 The problem with debugging information is that is takes up a fair amount
40515 of disk space. For example, debugging information for the GNU C Library
40516 weighs in at more than 60 MiB@. Thus, as a user, keeping all the
40517 debugging info of all the installed programs is usually not an option.
40518 Yet, space savings should not come at the cost of an impediment to
40519 debugging---especially in the GNU system, which should make it easier
40520 for users to exert their computing freedom (@pxref{GNU Distribution}).
40522 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
40523 mechanism that allows users to get the best of both worlds: debugging
40524 information can be stripped from the binaries and stored in separate
40525 files. GDB is then able to load debugging information from those files,
40526 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
40529 The GNU distribution takes advantage of this by storing debugging
40530 information in the @code{lib/debug} sub-directory of a separate package
40531 output unimaginatively called @code{debug} (@pxref{Packages with
40532 Multiple Outputs}). Users can choose to install the @code{debug} output
40533 of a package when they need it. For instance, the following command
40534 installs the debugging information for the GNU C Library and for GNU
40538 guix install glibc:debug guile:debug
40541 GDB must then be told to look for debug files in the user's profile, by
40542 setting the @code{debug-file-directory} variable (consider setting it
40543 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
40547 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
40550 From there on, GDB will pick up debugging information from the
40551 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
40553 Below is an alternative GDB script which is useful when working with
40554 other profiles. It takes advantage of the optional Guile integration in
40555 GDB. This snippet is included by default on Guix System in the
40556 @file{~/.gdbinit} file.
40560 (use-modules (gdb))
40561 (execute (string-append "set debug-file-directory "
40562 (or (getenv "GDB_DEBUG_FILE_DIRECTORY")
40563 "~/.guix-profile/lib/debug")))
40567 In addition, you will most likely want GDB to be able to show the source
40568 code being debugged. To do that, you will have to unpack the source
40569 code of the package of interest (obtained with @code{guix build
40570 --source}, @pxref{Invoking guix build}), and to point GDB to that source
40571 directory using the @code{directory} command (@pxref{Source Path,
40572 @code{directory},, gdb, Debugging with GDB}).
40574 @c XXX: keep me up-to-date
40575 The @code{debug} output mechanism in Guix is implemented by the
40576 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
40577 opt-in---debugging information is available only for the packages with
40578 definitions explicitly declaring a @code{debug} output. To check
40579 whether a package has a @code{debug} output, use @command{guix package
40580 --list-available} (@pxref{Invoking guix package}).
40582 Read on for how to deal with packages lacking a @code{debug} output.
40584 @node Rebuilding Debug Info
40585 @section Rebuilding Debug Info
40587 @cindex debugging info, rebuilding
40588 As we saw above, some packages, but not all, provide debugging info in a
40589 @code{debug} output. What can you do when debugging info is missing?
40590 The @option{--with-debug-info} option provides a solution to that: it
40591 allows you to rebuild the package(s) for which debugging info is
40592 missing---and only those---and to graft those onto the application
40593 you're debugging. Thus, while it's not as fast as installing a
40594 @code{debug} output, it is relatively inexpensive.
40596 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
40597 and would like to see what's going on in GLib, a library that's deep
40598 down in its dependency graph. As it turns out, GLib does not have a
40599 @code{debug} output and the backtrace GDB shows is all sadness:
40603 #0 0x00007ffff5f92190 in g_getenv ()
40604 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
40605 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
40606 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
40607 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
40608 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
40609 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
40613 To address that, you install Inkscape linked against a variant GLib that
40614 contains debug info:
40617 guix install inkscape --with-debug-info=glib
40620 This time, debugging will be a whole lot nicer:
40623 $ gdb --args sh -c 'exec inkscape'
40626 Function "g_getenv" not defined.
40627 Make breakpoint pending on future shared library load? (y or [n]) y
40628 Breakpoint 1 (g_getenv) pending.
40630 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
40633 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
40634 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
40635 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
40636 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
40637 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
40643 Note that there can be packages for which @option{--with-debug-info}
40644 will not have the desired effect. @xref{Package Transformation Options,
40645 @option{--with-debug-info}}, for more information.
40647 @node Using TeX and LaTeX
40648 @chapter Using @TeX{} and @LaTeX{}
40650 @cindex @TeX{} packages
40651 @cindex @LaTeX{} packages
40652 Guix provides packages for the @TeX{}, @LaTeX{}, ConTeXt, LuaTeX, and
40653 related typesetting systems, taken from the
40654 @uref{https://www.tug.org/texlive/, @TeX{} Live distribution}. However,
40655 because @TeX{} Live is so huge and because finding your way in this maze
40656 is tricky, we thought that you, dear user, would welcome guidance on how
40657 to deploy the relevant packages so you can compile your @TeX{} and
40658 @LaTeX{} documents.
40660 @TeX{} Live currently comes in two flavors in Guix:
40664 The ``monolithic'' @code{texlive} package: it comes with @emph{every
40665 single @TeX{} Live package} (more than 7,000 of them), but it is huge
40666 (more than 4@tie{}GiB for a single package!).
40669 The ``modular'' @code{texlive-} packages: you install
40670 @code{texlive-base}, which provides core functionality and the main
40671 commands---@command{pdflatex}, @command{dvips}, @command{luatex},
40672 @command{mf}, etc.---together with individual packages that provide just
40673 the features you need---@code{texlive-listings} for the
40674 @code{listings} package, @code{texlive-hyperref} for @code{hyperref},
40675 @code{texlive-beamer} for Beamer, @code{texlive-pgf} for PGF/TikZ,
40679 We recommend using the modular package set because it is much less
40680 resource-hungry. To build your documents, you would use commands such
40684 guix shell texlive-base texlive-wrapfig \
40685 texlive-hyperref texlive-cm-super -- pdflatex doc.tex
40688 You can quickly end up with unreasonably long command lines though. The
40689 solution is to instead write a manifest, for example like this one:
40692 (specifications->manifest
40698 "texlive-microtype"
40699 "texlive-listings" "texlive-hyperref"
40704 ;; Additional fonts.
40705 "texlive-cm-super" "texlive-amsfonts"
40706 "texlive-times" "texlive-helvetic" "texlive-courier"))
40709 You can then pass it to any command with the @option{-m} option:
40712 guix shell -m manifest.scm -- pdflatex doc.tex
40715 @xref{Writing Manifests}, for more on
40716 manifests. In the future, we plan to provide packages for @TeX{} Live
40717 @dfn{collections}---``meta-packages'' such as @code{fontsrecommended},
40718 @code{humanities}, or @code{langarabic} that provide the set of packages
40719 needed in this particular domain. That will allow you to list fewer
40722 The main difficulty here is that using the modular package set forces
40723 you to select precisely the packages that you need. You can use
40724 @command{guix search}, but finding the right package can prove to be
40725 tedious. When a package is missing, @command{pdflatex} and similar
40726 commands fail with an obscure message along the lines of:
40729 doc.tex: File `tikz.sty' not found.
40730 doc.tex:7: Emergency stop.
40734 or, for a missing font:
40737 kpathsea: Running mktexmf phvr7t
40738 ! I can't find file `phvr7t'.
40741 How do you determine what the missing package is? In the first case,
40742 you'll find the answer by running:
40745 $ guix search texlive tikz
40751 In the second case, @command{guix search} turns up nothing. Instead,
40752 you can search the @TeX{} Live package database using the @command{tlmgr}
40756 $ guix shell texlive-base -- tlmgr info phvr7t
40757 tlmgr: cannot find package phvr7t, searching for other matches:
40759 Packages containing `phvr7t' in their title/description:
40761 Packages containing files matching `phvr7t':
40763 texmf-dist/fonts/tfm/adobe/helvetic/phvr7t.tfm
40764 texmf-dist/fonts/tfm/adobe/helvetic/phvr7tn.tfm
40765 texmf-dist/fonts/vf/adobe/helvetic/phvr7t.vf
40766 texmf-dist/fonts/vf/adobe/helvetic/phvr7tn.vf
40768 texmf-dist/tex4ht/ht-fonts/alias/adobe/helvetic/phvr7t.htf
40771 The file is available in the @TeX{} Live @code{helvetic} package, which is
40772 known in Guix as @code{texlive-helvetic}. Quite a ride, but we found
40775 There is one important limitation though: Guix currently provides a
40776 subset of the @TeX{} Live packages. If you stumble upon a missing
40777 package, you can try and import it (@pxref{Invoking guix import}):
40780 guix import texlive @var{package}
40783 Additional options include:
40788 Traverse the dependency graph of the given upstream package recursively
40789 and generate package expressions for all those packages that are not yet
40794 @TeX{} Live packaging is still very much work in progress, but you can
40795 help! @xref{Contributing}, for more information.
40798 @node Security Updates
40799 @chapter Security Updates
40801 @cindex security updates
40802 @cindex security vulnerabilities
40803 Occasionally, important security vulnerabilities are discovered in software
40804 packages and must be patched. Guix developers try hard to keep track of
40805 known vulnerabilities and to apply fixes as soon as possible in the
40806 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
40807 containing only security updates). The @command{guix lint} tool helps
40808 developers find out about vulnerable versions of software packages in the
40813 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
40814 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
40815 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
40819 @xref{Invoking guix lint}, for more information.
40821 Guix follows a functional
40822 package management discipline (@pxref{Introduction}), which implies
40823 that, when a package is changed, @emph{every package that depends on it}
40824 must be rebuilt. This can significantly slow down the deployment of
40825 fixes in core packages such as libc or Bash, since basically the whole
40826 distribution would need to be rebuilt. Using pre-built binaries helps
40827 (@pxref{Substitutes}), but deployment may still take more time than
40831 To address this, Guix implements @dfn{grafts}, a mechanism that allows
40832 for fast deployment of critical updates without the costs associated
40833 with a whole-distribution rebuild. The idea is to rebuild only the
40834 package that needs to be patched, and then to ``graft'' it onto packages
40835 explicitly installed by the user and that were previously referring to
40836 the original package. The cost of grafting is typically very low, and
40837 order of magnitudes lower than a full rebuild of the dependency chain.
40839 @cindex replacements of packages, for grafts
40840 For instance, suppose a security update needs to be applied to Bash.
40841 Guix developers will provide a package definition for the ``fixed''
40842 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
40843 Packages}). Then, the original package definition is augmented with a
40844 @code{replacement} field pointing to the package containing the bug fix:
40851 (replacement bash-fixed)))
40854 From there on, any package depending directly or indirectly on Bash---as
40855 reported by @command{guix gc --requisites} (@pxref{Invoking guix
40856 gc})---that is installed is automatically ``rewritten'' to refer to
40857 @code{bash-fixed} instead of @code{bash}. This grafting process takes
40858 time proportional to the size of the package, usually less than a
40859 minute for an ``average'' package on a recent machine. Grafting is
40860 recursive: when an indirect dependency requires grafting, then grafting
40861 ``propagates'' up to the package that the user is installing.
40863 Currently, the length of the name and version of the graft and that of
40864 the package it replaces (@code{bash-fixed} and @code{bash} in the example
40865 above) must be equal. This restriction mostly comes from the fact that
40866 grafting works by patching files, including binary files, directly.
40867 Other restrictions may apply: for instance, when adding a graft to a
40868 package providing a shared library, the original shared library and its
40869 replacement must have the same @code{SONAME} and be binary-compatible.
40871 The @option{--no-grafts} command-line option allows you to forcefully
40872 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
40876 guix build bash --no-grafts
40880 returns the store file name of the original Bash, whereas:
40887 returns the store file name of the ``fixed'', replacement Bash. This
40888 allows you to distinguish between the two variants of Bash.
40890 To verify which Bash your whole profile refers to, you can run
40891 (@pxref{Invoking guix gc}):
40894 guix gc -R $(readlink -f ~/.guix-profile) | grep bash
40898 @dots{} and compare the store file names that you get with those above.
40899 Likewise for a complete Guix system generation:
40902 guix gc -R $(guix system build my-config.scm) | grep bash
40905 Lastly, to check which Bash running processes are using, you can use the
40906 @command{lsof} command:
40909 lsof | grep /gnu/store/.*bash
40913 @node Bootstrapping
40914 @chapter Bootstrapping
40916 @c Adapted from the ELS 2013 paper.
40918 @cindex bootstrapping
40920 Bootstrapping in our context refers to how the distribution gets built
40921 ``from nothing''. Remember that the build environment of a derivation
40922 contains nothing but its declared inputs (@pxref{Introduction}). So
40923 there's an obvious chicken-and-egg problem: how does the first package
40924 get built? How does the first compiler get compiled?
40926 It is tempting to think of this question as one that only die-hard
40927 hackers may care about. However, while the answer to that question is
40928 technical in nature, its implications are wide-ranging. How the
40929 distribution is bootstrapped defines the extent to which we, as
40930 individuals and as a collective of users and hackers, can trust the
40931 software we run. It is a central concern from the standpoint of
40932 @emph{security} and from a @emph{user freedom} viewpoint.
40934 @cindex bootstrap binaries
40935 The GNU system is primarily made of C code, with libc at its core. The
40936 GNU build system itself assumes the availability of a Bourne shell and
40937 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
40938 `grep'. Furthermore, build programs---programs that run
40939 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
40940 (@pxref{Derivations}). Consequently, to be able to build anything at
40941 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
40942 Binutils, libc, and the other packages mentioned above---the
40943 @dfn{bootstrap binaries}.
40945 These bootstrap binaries are ``taken for granted'', though we can also
40946 re-create them if needed (@pxref{Preparing to Use the Bootstrap
40950 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
40951 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
40954 @node Reduced Binary Seed Bootstrap
40955 @section The Reduced Binary Seed Bootstrap
40957 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
40958 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
40959 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
40960 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
40961 ``taken for granted.''
40963 Taking the bootstrap binaries for granted means that we consider them to
40964 be a correct and trustworthy ``seed'' for building the complete system.
40965 Therein lies a problem: the combined size of these bootstrap binaries is
40966 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
40967 or even inspecting these is next to impossible.
40969 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
40970 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
40971 Source Bootstrap'' and while we are working towards that goal it would
40972 be hyperbole to use that term for what we do now.}.
40974 The Reduced Binary Seed bootstrap removes the most critical tools---from a
40975 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
40976 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
40977 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
40978 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
40980 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
40981 C Library are built from source. From here on the more traditional
40982 bootstrap process resumes. This approach has reduced the bootstrap
40983 binaries in size to about 145MB in Guix v1.1.
40985 The next step that Guix has taken is to replace the shell and all its
40986 utilities with implementations in Guile Scheme, the @emph{Scheme-only
40987 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
40988 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
40989 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
40990 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
40991 removed are now built from source.
40993 Building the GNU System from source is currently only possible by adding
40994 some historical GNU packages as intermediate steps@footnote{Packages
40995 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
40996 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
40997 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
40998 and GNU packages become more bootstrappable again (e.g., new releases of
40999 GNU Sed will also ship as gzipped tarballs again, as alternative to the
41000 hard to bootstrap @code{xz}-compression), this set of added packages can
41001 hopefully be reduced again.
41003 The graph below shows the resulting dependency graph for
41004 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
41005 traditional bootstrap of the rest of the Guix System.
41007 @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
41008 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
41010 The only significant binary bootstrap seeds that remain@footnote{
41011 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
41012 together with @code{mes}.} are a Scheme interpreter and a Scheme
41013 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
41014 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
41015 to get Guile running.}.
41017 This further reduction has brought down the size of the binary seed to
41018 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
41020 Work is ongoing to remove all binary blobs from our free software
41021 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
41022 is work to bring these bootstraps to the @code{arm-linux} and
41023 @code{aarch64-linux} architectures and to the Hurd.
41025 If you are interested, join us on @samp{#bootstrappable} on the Freenode
41026 IRC network or discuss on @email{bug-mes@@gnu.org} or
41027 @email{gash-devel@@nongnu.org}.
41029 @node Preparing to Use the Bootstrap Binaries
41030 @section Preparing to Use the Bootstrap Binaries
41032 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
41033 @c large image, it's hard to scroll. Oh well.
41034 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
41036 The figure above shows the very beginning of the dependency graph of the
41037 distribution, corresponding to the package definitions of the @code{(gnu
41038 packages bootstrap)} module. A similar figure can be generated with
41039 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
41042 guix graph -t derivation \
41043 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
41044 | dot -Tps > gcc.ps
41047 or, for the further Reduced Binary Seed bootstrap
41050 guix graph -t derivation \
41051 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
41052 | dot -Tps > mes.ps
41055 At this level of detail, things are
41056 slightly complex. First, Guile itself consists of an ELF executable,
41057 along with many source and compiled Scheme files that are dynamically
41058 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
41059 tarball shown in this graph. This tarball is part of Guix's ``source''
41060 distribution, and gets inserted into the store with @code{add-to-store}
41061 (@pxref{The Store}).
41063 But how do we write a derivation that unpacks this tarball and adds it
41064 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
41065 derivation---the first one that gets built---uses @code{bash} as its
41066 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
41067 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
41068 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
41069 the Guix source distribution, whose sole purpose is to allow the Guile
41070 tarball to be unpacked.
41072 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
41073 Guile that can be used to run subsequent build programs. Its first task
41074 is to download tarballs containing the other pre-built binaries---this
41075 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
41076 @code{ftp-client.scm} are used for this purpose. The
41077 @code{module-import.drv} derivations import those modules in a directory
41078 in the store, using the original layout. The
41079 @code{module-import-compiled.drv} derivations compile those modules, and
41080 write them in an output directory with the right layout. This
41081 corresponds to the @code{#:modules} argument of
41082 @code{build-expression->derivation} (@pxref{Derivations}).
41084 Finally, the various tarballs are unpacked by the derivations
41085 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
41086 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
41087 point we have a working C tool chain.
41089 @unnumberedsec Building the Build Tools
41091 Bootstrapping is complete when we have a full tool chain that does not
41092 depend on the pre-built bootstrap tools discussed above. This
41093 no-dependency requirement is verified by checking whether the files of
41094 the final tool chain contain references to the @file{/gnu/store}
41095 directories of the bootstrap inputs. The process that leads to this
41096 ``final'' tool chain is described by the package definitions found in
41097 the @code{(gnu packages commencement)} module.
41099 The @command{guix graph} command allows us to ``zoom out'' compared to
41100 the graph above, by looking at the level of package objects instead of
41101 individual derivations---remember that a package may translate to
41102 several derivations, typically one derivation to download its source,
41103 one to build the Guile modules it needs, and one to actually build the
41104 package from source. The command:
41107 guix graph -t bag \
41108 -e '(@@@@ (gnu packages commencement)
41109 glibc-final-with-bootstrap-bash)' | xdot -
41113 displays the dependency graph leading to the ``final'' C
41114 library@footnote{You may notice the @code{glibc-intermediate} label,
41115 suggesting that it is not @emph{quite} final, but as a good
41116 approximation, we will consider it final.}, depicted below.
41118 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
41120 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
41121 The first tool that gets built with the bootstrap binaries is
41122 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
41123 for all the following packages. From there Findutils and Diffutils get
41126 Then come the first-stage Binutils and GCC, built as pseudo cross
41127 tools---i.e., with @option{--target} equal to @option{--host}. They are
41128 used to build libc. Thanks to this cross-build trick, this libc is
41129 guaranteed not to hold any reference to the initial tool chain.
41131 From there the final Binutils and GCC (not shown above) are built. GCC
41132 uses @command{ld} from the final Binutils, and links programs against
41133 the just-built libc. This tool chain is used to build the other
41134 packages used by Guix and by the GNU Build System: Guile, Bash,
41137 And voilà! At this point we have the complete set of build tools that
41138 the GNU Build System expects. These are in the @code{%final-inputs}
41139 variable of the @code{(gnu packages commencement)} module, and are
41140 implicitly used by any package that uses @code{gnu-build-system}
41141 (@pxref{Build Systems, @code{gnu-build-system}}).
41144 @unnumberedsec Building the Bootstrap Binaries
41146 @cindex bootstrap binaries
41147 Because the final tool chain does not depend on the bootstrap binaries,
41148 those rarely need to be updated. Nevertheless, it is useful to have an
41149 automated way to produce them, should an update occur, and this is what
41150 the @code{(gnu packages make-bootstrap)} module provides.
41152 The following command builds the tarballs containing the bootstrap binaries
41153 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
41154 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
41155 and Guile, and a tarball containing a mixture of Coreutils and other basic
41156 command-line tools):
41159 guix build bootstrap-tarballs
41162 The generated tarballs are those that should be referred to in the
41163 @code{(gnu packages bootstrap)} module mentioned at the beginning of
41166 Still here? Then perhaps by now you've started to wonder: when do we
41167 reach a fixed point? That is an interesting question! The answer is
41168 unknown, but if you would like to investigate further (and have
41169 significant computational and storage resources to do so), then let us
41172 @unnumberedsec Reducing the Set of Bootstrap Binaries
41174 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
41175 binary code! Why is that a problem? It's a problem because these big chunks
41176 of binary code are practically non-auditable, which makes it hard to establish
41177 what source code produced them. Every unauditable binary also leaves us
41178 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
41179 paper @emph{Reflections on Trusting Trust}.
41181 This is mitigated by the fact that our bootstrap binaries were generated
41182 from an earlier Guix revision. Nevertheless it lacks the level of
41183 transparency that we get in the rest of the package dependency graph,
41184 where Guix always gives us a source-to-binary mapping. Thus, our goal
41185 is to reduce the set of bootstrap binaries to the bare minimum.
41187 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
41188 on-going projects to do that. One of these is about replacing the
41189 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
41190 of increasing complexity, which could be built from source starting from
41191 a simple and auditable assembler.
41193 Our first major achievement is the replacement of of GCC, the GNU C Library
41194 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
41195 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
41196 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
41197 bootstrapped yet and thus we inject them as binary seeds. We call this the
41198 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
41199 binaries! Also, it has eliminated the C compiler binary; i686-linux and
41200 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
41202 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
41203 also looking at any other bootstrap binaries. Your help is welcome!
41206 @chapter Porting to a New Platform
41208 As discussed above, the GNU distribution is self-contained, and
41209 self-containment is achieved by relying on pre-built ``bootstrap
41210 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
41211 operating system kernel, CPU architecture, and application binary
41212 interface (ABI). Thus, to port the distribution to a platform that is
41213 not yet supported, one must build those bootstrap binaries, and update
41214 the @code{(gnu packages bootstrap)} module to use them on that platform.
41216 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
41217 When everything goes well, and assuming the GNU tool chain supports the
41218 target platform, this can be as simple as running a command like this
41222 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
41225 For this to work, it is first required to register a new platform as
41226 defined in the @code{(guix platform)} module. A platform is making the
41227 connection between a GNU triplet (@pxref{Specifying Target Triplets, GNU
41228 configuration triplets,, autoconf, Autoconf}), the equivalent
41229 @var{system} in Nix notation, the name of the
41230 @var{glibc-dynamic-linker}, and the corresponding Linux architecture
41231 name if applicable.
41233 Once the bootstrap tarball are built, the @code{(gnu packages
41234 bootstrap)} module needs to be updated to refer to these binaries on the
41235 target platform. That is, the hashes and URLs of the bootstrap tarballs
41236 for the new platform must be added alongside those of the currently
41237 supported platforms. The bootstrap Guile tarball is treated specially:
41238 it is expected to be available locally, and @file{gnu/local.mk} has
41239 rules to download it for the supported architectures; a rule for the new
41240 platform must be added as well.
41242 In practice, there may be some complications. First, it may be that the
41243 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
41244 above) is not recognized by all the GNU tools. Typically, glibc
41245 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
41246 configure flag (see @code{gcc.scm} for examples of how to handle this).
41247 Second, some of the required packages could fail to build for that
41248 platform. Lastly, the generated binaries could be broken for some
41251 @c *********************************************************************
41252 @include contributing.texi
41254 @c *********************************************************************
41255 @node Acknowledgments
41256 @chapter Acknowledgments
41258 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
41259 which was designed and
41260 implemented by Eelco Dolstra, with contributions from other people (see
41261 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
41262 management, and promoted unprecedented features, such as transactional
41263 package upgrades and rollbacks, per-user profiles, and referentially
41264 transparent build processes. Without this work, Guix would not exist.
41266 The Nix-based software distributions, Nixpkgs and NixOS, have also been
41267 an inspiration for Guix.
41269 GNU@tie{}Guix itself is a collective work with contributions from a
41270 number of people. See the @file{AUTHORS} file in Guix for more
41271 information on these fine people. The @file{THANKS} file lists people
41272 who have helped by reporting bugs, taking care of the infrastructure,
41273 providing artwork and themes, making suggestions, and more---thank you!
41276 @c *********************************************************************
41277 @node GNU Free Documentation License
41278 @appendix GNU Free Documentation License
41279 @cindex license, GNU Free Documentation License
41280 @include fdl-1.3.texi
41282 @c *********************************************************************
41283 @node Concept Index
41284 @unnumbered Concept Index
41287 @node Programming Index
41288 @unnumbered Programming Index
41289 @syncodeindex tp fn
41290 @syncodeindex vr fn
41295 @c Local Variables:
41296 @c ispell-local-dictionary: "american";