6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
14 @set KEY-SERVER pool.sks-keyservers.net
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER ci.guix.gnu.org
21 @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
24 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès@*
25 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
26 Copyright @copyright{} 2013 Nikita Karetnikov@*
27 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
28 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
29 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
30 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
31 Copyright @copyright{} 2015, 2016, 2017 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 ng0@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017 Christopher Allan Webber@*
49 Copyright @copyright{} 2017, 2018 Marius Bakke@*
50 Copyright @copyright{} 2017 Hartmut Goebel@*
51 Copyright @copyright{} 2017 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018 Tobias Geerinckx-Rice@*
53 Copyright @copyright{} 2017 George Clemmer@*
54 Copyright @copyright{} 2017 Andy Wingo@*
55 Copyright @copyright{} 2017, 2018, 2019 Arun Isaac@*
56 Copyright @copyright{} 2017 nee@*
57 Copyright @copyright{} 2018 Rutger Helling@*
58 Copyright @copyright{} 2018 Oleg Pykhalov@*
59 Copyright @copyright{} 2018 Mike Gerwitz@*
60 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
61 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
62 Copyright @copyright{} 2018, 2019 Florian Pelz@*
63 Copyright @copyright{} 2018 Laura Lazzati@*
64 Copyright @copyright{} 2018 Alex Vong@*
65 Copyright @copyright{} 2019 Josh Holland@*
66 Copyright @copyright{} 2019 Diego Nicola Barbato@*
67 Copyright @copyright{} 2019 Ivan Petkov@*
69 Permission is granted to copy, distribute and/or modify this document
70 under the terms of the GNU Free Documentation License, Version 1.3 or
71 any later version published by the Free Software Foundation; with no
72 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
73 copy of the license is included in the section entitled ``GNU Free
74 Documentation License''.
77 @dircategory System administration
79 * Guix: (guix). Manage installed software and system configuration.
80 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
81 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
82 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
83 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
86 @dircategory Software development
88 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
89 * guix build: (guix)Invoking guix build. Building packages.
90 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
94 @title GNU Guix Reference Manual
95 @subtitle Using the GNU Guix Functional Package Manager
96 @author The GNU Guix Developers
99 @vskip 0pt plus 1filll
100 Edition @value{EDITION} @*
108 @c *********************************************************************
112 This document describes GNU Guix version @value{VERSION}, a functional
113 package management tool written for the GNU system.
115 @c TRANSLATORS: You can replace the following paragraph with information on
116 @c how to join your own translation team and how to report issues with the
118 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
119 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
120 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
121 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
122 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
123 would like to translate it in your native language, consider joining the
124 @uref{https://translationproject.org/domain/guix-manual.html, Translation
128 * Introduction:: What is Guix about?
129 * Installation:: Installing Guix.
130 * System Installation:: Installing the whole operating system.
131 * Package Management:: Package installation, upgrade, etc.
132 * Development:: Guix-aided software development.
133 * Programming Interface:: Using Guix in Scheme.
134 * Utilities:: Package management commands.
135 * System Configuration:: Configuring the operating system.
136 * Documentation:: Browsing software user manuals.
137 * Installing Debugging Files:: Feeding the debugger.
138 * Security Updates:: Deploying security fixes quickly.
139 * Bootstrapping:: GNU/Linux built from scratch.
140 * Porting:: Targeting another platform or kernel.
141 * Contributing:: Your help needed!
143 * Acknowledgments:: Thanks!
144 * GNU Free Documentation License:: The license of this manual.
145 * Concept Index:: Concepts.
146 * Programming Index:: Data types, functions, and variables.
149 --- The Detailed Node Listing ---
153 * Managing Software the Guix Way:: What's special.
154 * GNU Distribution:: The packages and tools.
158 * Binary Installation:: Getting Guix running in no time!
159 * Requirements:: Software needed to build and run Guix.
160 * Running the Test Suite:: Testing Guix.
161 * Setting Up the Daemon:: Preparing the build daemon's environment.
162 * Invoking guix-daemon:: Running the build daemon.
163 * Application Setup:: Application-specific setup.
165 Setting Up the Daemon
167 * Build Environment Setup:: Preparing the isolated build environment.
168 * Daemon Offload Setup:: Offloading builds to remote machines.
169 * SELinux Support:: Using an SELinux policy for the daemon.
173 * Limitations:: What you can expect.
174 * Hardware Considerations:: Supported hardware.
175 * USB Stick and DVD Installation:: Preparing the installation medium.
176 * Preparing for Installation:: Networking, partitioning, etc.
177 * Guided Graphical Installation:: Easy graphical installation.
178 * Manual Installation:: Manual installation for wizards.
179 * After System Installation:: When installation succeeded.
180 * Installing Guix in a VM:: Guix System playground.
181 * Building the Installation Image:: How this comes to be.
185 * Keyboard Layout and Networking and Partitioning:: Initial setup.
186 * Proceeding with the Installation:: Installing.
190 * Features:: How Guix will make your life brighter.
191 * Invoking guix package:: Package installation, removal, etc.
192 * Substitutes:: Downloading pre-built binaries.
193 * Packages with Multiple Outputs:: Single source package, multiple outputs.
194 * Invoking guix gc:: Running the garbage collector.
195 * Invoking guix pull:: Fetching the latest Guix and distribution.
196 * Channels:: Customizing the package collection.
197 * Inferiors:: Interacting with another revision of Guix.
198 * Invoking guix describe:: Display information about your Guix revision.
199 * Invoking guix archive:: Exporting and importing store files.
203 * Official Substitute Server:: One particular source of substitutes.
204 * Substitute Server Authorization:: How to enable or disable substitutes.
205 * Substitute Authentication:: How Guix verifies substitutes.
206 * Proxy Settings:: How to get substitutes via proxy.
207 * Substitution Failure:: What happens when substitution fails.
208 * On Trusting Binaries:: How can you trust that binary blob?
212 * Invoking guix environment:: Setting up development environments.
213 * Invoking guix pack:: Creating software bundles.
215 Programming Interface
217 * Package Modules:: Packages from the programmer's viewpoint.
218 * Defining Packages:: Defining new packages.
219 * Build Systems:: Specifying how packages are built.
220 * The Store:: Manipulating the package store.
221 * Derivations:: Low-level interface to package derivations.
222 * The Store Monad:: Purely functional interface to the store.
223 * G-Expressions:: Manipulating build expressions.
224 * Invoking guix repl:: Fiddling with Guix interactively.
228 * package Reference:: The package data type.
229 * origin Reference:: The origin data type.
233 * Invoking guix build:: Building packages from the command line.
234 * Invoking guix edit:: Editing package definitions.
235 * Invoking guix download:: Downloading a file and printing its hash.
236 * Invoking guix hash:: Computing the cryptographic hash of a file.
237 * Invoking guix import:: Importing package definitions.
238 * Invoking guix refresh:: Updating package definitions.
239 * Invoking guix lint:: Finding errors in package definitions.
240 * Invoking guix size:: Profiling disk usage.
241 * Invoking guix graph:: Visualizing the graph of packages.
242 * Invoking guix publish:: Sharing substitutes.
243 * Invoking guix challenge:: Challenging substitute servers.
244 * Invoking guix copy:: Copying to and from a remote store.
245 * Invoking guix container:: Process isolation.
246 * Invoking guix weather:: Assessing substitute availability.
247 * Invoking guix processes:: Listing client processes.
249 Invoking @command{guix build}
251 * Common Build Options:: Build options for most commands.
252 * Package Transformation Options:: Creating variants of packages.
253 * Additional Build Options:: Options specific to 'guix build'.
254 * Debugging Build Failures:: Real life packaging experience.
258 * Using the Configuration System:: Customizing your GNU system.
259 * operating-system Reference:: Detail of operating-system declarations.
260 * File Systems:: Configuring file system mounts.
261 * Mapped Devices:: Block device extra processing.
262 * User Accounts:: Specifying user accounts.
263 * Keyboard Layout:: How the system interprets key strokes.
264 * Locales:: Language and cultural convention settings.
265 * Services:: Specifying system services.
266 * Setuid Programs:: Programs running with root privileges.
267 * X.509 Certificates:: Authenticating HTTPS servers.
268 * Name Service Switch:: Configuring libc's name service switch.
269 * Initial RAM Disk:: Linux-Libre bootstrapping.
270 * Bootloader Configuration:: Configuring the boot loader.
271 * Invoking guix system:: Instantiating a system configuration.
272 * Running Guix in a VM:: How to run Guix System in a virtual machine.
273 * Defining Services:: Adding new service definitions.
277 * Base Services:: Essential system services.
278 * Scheduled Job Execution:: The mcron service.
279 * Log Rotation:: The rottlog service.
280 * Networking Services:: Network setup, SSH daemon, etc.
281 * X Window:: Graphical display.
282 * Printing Services:: Local and remote printer support.
283 * Desktop Services:: D-Bus and desktop services.
284 * Sound Services:: ALSA and Pulseaudio services.
285 * Database Services:: SQL databases, key-value stores, etc.
286 * Mail Services:: IMAP, POP3, SMTP, and all that.
287 * Messaging Services:: Messaging services.
288 * Telephony Services:: Telephony services.
289 * Monitoring Services:: Monitoring services.
290 * Kerberos Services:: Kerberos services.
291 * Web Services:: Web servers.
292 * Certificate Services:: TLS certificates via Let's Encrypt.
293 * DNS Services:: DNS daemons.
294 * VPN Services:: VPN daemons.
295 * Network File System:: NFS related services.
296 * Continuous Integration:: The Cuirass service.
297 * Power Management Services:: Extending battery life.
298 * Audio Services:: The MPD.
299 * Virtualization Services:: Virtualization services.
300 * Version Control Services:: Providing remote access to Git repositories.
301 * Game Services:: Game servers.
302 * Miscellaneous Services:: Other services.
306 * Service Composition:: The model for composing services.
307 * Service Types and Services:: Types and services.
308 * Service Reference:: API reference.
309 * Shepherd Services:: A particular type of service.
314 @c *********************************************************************
316 @chapter Introduction
319 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
320 using the international phonetic alphabet (IPA).} is a package
321 management tool for and distribution of the GNU system.
322 Guix makes it easy for unprivileged
323 users to install, upgrade, or remove software packages, to roll back to a
324 previous package set, to build packages from source, and generally
325 assists with the creation and maintenance of software environments.
328 @cindex GuixSD, now Guix System
329 @cindex Guix System Distribution, now Guix System
330 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
331 complements the available tools without interference (@pxref{Installation}),
332 or you can use it as a standalone operating system distribution,
333 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
334 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
335 group everything under the ``Guix'' banner since, after all, Guix System is
336 readily available through the @command{guix system} command, even if you're
337 using a different distro underneath!}. @xref{GNU Distribution}.
340 * Managing Software the Guix Way:: What's special.
341 * GNU Distribution:: The packages and tools.
344 @node Managing Software the Guix Way
345 @section Managing Software the Guix Way
347 @cindex user interfaces
348 Guix provides a command-line package management interface
349 (@pxref{Package Management}), tools to help with software development
350 (@pxref{Development}), command-line utilities for more advanced usage,
351 (@pxref{Utilities}), as well as Scheme programming interfaces
352 (@pxref{Programming Interface}).
354 Its @dfn{build daemon} is responsible for building packages on behalf of
355 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
356 binaries from authorized sources (@pxref{Substitutes}).
358 @cindex extensibility of the distribution
359 @cindex customization, of packages
360 Guix includes package definitions for many GNU and non-GNU packages, all
361 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
362 user's computing freedom}. It is @emph{extensible}: users can write
363 their own package definitions (@pxref{Defining Packages}) and make them
364 available as independent package modules (@pxref{Package Modules}). It
365 is also @emph{customizable}: users can @emph{derive} specialized package
366 definitions from existing ones, including from the command line
367 (@pxref{Package Transformation Options}).
369 @cindex functional package management
371 Under the hood, Guix implements the @dfn{functional package management}
372 discipline pioneered by Nix (@pxref{Acknowledgments}).
373 In Guix, the package build and installation process is seen
374 as a @emph{function}, in the mathematical sense. That function takes inputs,
375 such as build scripts, a compiler, and libraries, and
376 returns an installed package. As a pure function, its result depends
377 solely on its inputs---for instance, it cannot refer to software or
378 scripts that were not explicitly passed as inputs. A build function
379 always produces the same result when passed a given set of inputs. It
380 cannot alter the environment of the running system in
381 any way; for instance, it cannot create, modify, or delete files outside
382 of its build and installation directories. This is achieved by running
383 build processes in isolated environments (or @dfn{containers}), where only their
384 explicit inputs are visible.
387 The result of package build functions is @dfn{cached} in the file
388 system, in a special directory called @dfn{the store} (@pxref{The
389 Store}). Each package is installed in a directory of its own in the
390 store---by default under @file{/gnu/store}. The directory name contains
391 a hash of all the inputs used to build that package; thus, changing an
392 input yields a different directory name.
394 This approach is the foundation for the salient features of Guix: support
395 for transactional package upgrade and rollback, per-user installation, and
396 garbage collection of packages (@pxref{Features}).
399 @node GNU Distribution
400 @section GNU Distribution
403 Guix comes with a distribution of the GNU system consisting entirely of
404 free software@footnote{The term ``free'' here refers to the
405 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
406 users of that software}.}. The
407 distribution can be installed on its own (@pxref{System Installation}),
408 but it is also possible to install Guix as a package manager on top of
409 an installed GNU/Linux system (@pxref{Installation}). When we need to
410 distinguish between the two, we refer to the standalone distribution as
413 The distribution provides core GNU packages such as GNU libc, GCC, and
414 Binutils, as well as many GNU and non-GNU applications. The complete
415 list of available packages can be browsed
416 @url{https://www.gnu.org/software/guix/packages,on-line} or by
417 running @command{guix package} (@pxref{Invoking guix package}):
420 guix package --list-available
423 Our goal is to provide a practical 100% free software distribution of
424 Linux-based and other variants of GNU, with a focus on the promotion and
425 tight integration of GNU components, and an emphasis on programs and
426 tools that help users exert that freedom.
428 Packages are currently available on the following platforms:
433 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
436 Intel 32-bit architecture (IA32), Linux-Libre kernel;
439 ARMv7-A architecture with hard float, Thumb-2 and NEON,
440 using the EABI hard-float application binary interface (ABI),
441 and Linux-Libre kernel.
444 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
447 little-endian 64-bit MIPS processors, specifically the Loongson series,
448 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
449 supported; in particular, the project's build farms no longer provide
450 substitutes for this architecture.
454 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
455 configuration and Guix takes care of instantiating the configuration in a
456 transactional, reproducible, and stateless fashion (@pxref{System
457 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
458 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
459 Manual}), the well-known GNU utilities and tool chain, as well as the
460 graphical environment or system services of your choice.
462 Guix System is available on all the above platforms except
463 @code{mips64el-linux}.
466 For information on porting to other architectures or kernels,
469 Building this distribution is a cooperative effort, and you are invited
470 to join! @xref{Contributing}, for information about how you can help.
473 @c *********************************************************************
475 @chapter Installation
477 @cindex installing Guix
480 We recommend the use of this
481 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
482 shell installer script} to install Guix on top of a running GNU/Linux system,
483 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
484 with the installation of the package manager, which can be done on top of a
485 running GNU/Linux system. If, instead, you want to install the complete GNU
486 operating system, @pxref{System Installation}.} The script automates the
487 download, installation, and initial configuration of Guix. It should be run
491 @cindex foreign distro
492 @cindex directories related to foreign distro
493 When installed on a foreign distro, GNU@tie{}Guix complements the available
494 tools without interference. Its data lives exclusively in two directories,
495 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
496 such as @file{/etc}, are left untouched.
498 Once installed, Guix can be updated by running @command{guix pull}
499 (@pxref{Invoking guix pull}).
501 If you prefer to perform the installation steps manually or want to tweak
502 them, you may find the following subsections useful. They describe the
503 software requirements of Guix, as well as how to install it manually and get
507 * Binary Installation:: Getting Guix running in no time!
508 * Requirements:: Software needed to build and run Guix.
509 * Running the Test Suite:: Testing Guix.
510 * Setting Up the Daemon:: Preparing the build daemon's environment.
511 * Invoking guix-daemon:: Running the build daemon.
512 * Application Setup:: Application-specific setup.
515 @node Binary Installation
516 @section Binary Installation
518 @cindex installing Guix from binaries
519 @cindex installer script
520 This section describes how to install Guix on an arbitrary system from a
521 self-contained tarball providing binaries for Guix and for all its
522 dependencies. This is often quicker than installing from source, which
523 is described in the next sections. The only requirement is to have
526 @c Note duplicated from the ``Installation'' node.
528 We recommend the use of this
529 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
530 shell installer script}. The script automates the download, installation, and
531 initial configuration steps described below. It should be run as the root
535 Installing goes along these lines:
539 @cindex downloading Guix binary
540 Download the binary tarball from
541 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz},
542 where @var{system} is @code{x86_64-linux} for an @code{x86_64} machine
543 already running the kernel Linux, and so on.
545 @c The following is somewhat duplicated in ``System Installation''.
546 Make sure to download the associated @file{.sig} file and to verify the
547 authenticity of the tarball against it, along these lines:
550 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
551 $ gpg --verify guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
554 If that command fails because you do not have the required public key,
555 then run this command to import it:
558 $ gpg --keyserver @value{KEY-SERVER} \
559 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
563 and rerun the @code{gpg --verify} command.
564 @c end authentication part
567 Now, you need to become the @code{root} user. Depending on your distribution,
568 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
572 # tar --warning=no-timestamp -xf \
573 /path/to/guix-binary-@value{VERSION}.@var{system}.tar.xz
574 # mv var/guix /var/ && mv gnu /
577 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
578 The latter contains a ready-to-use profile for @code{root} (see next
581 Do @emph{not} unpack the tarball on a working Guix system since that
582 would overwrite its own essential files.
584 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
585 not emit warnings about ``implausibly old time stamps'' (such
586 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
588 They stem from the fact that all the
589 files in the archive have their modification time set to zero (which
590 means January 1st, 1970.) This is done on purpose to make sure the
591 archive content is independent of its creation time, thus making it
595 Make the profile available under @file{~root/.config/guix/current}, which is
596 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
599 # mkdir -p ~root/.config/guix
600 # ln -sf /var/guix/profiles/per-user/root/current-guix \
601 ~root/.config/guix/current
604 Source @file{etc/profile} to augment @code{PATH} and other relevant
605 environment variables:
608 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
609 source $GUIX_PROFILE/etc/profile
613 Create the group and user accounts for build users as explained below
614 (@pxref{Build Environment Setup}).
617 Run the daemon, and set it to automatically start on boot.
619 If your host distro uses the systemd init system, this can be achieved
622 @c Versions of systemd that supported symlinked service files are not
623 @c yet widely deployed, so we should suggest that users copy the service
626 @c See this thread for more information:
627 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
630 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
632 # systemctl start guix-daemon && systemctl enable guix-daemon
635 If your host distro uses the Upstart init system:
638 # initctl reload-configuration
639 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
644 Otherwise, you can still start the daemon manually with:
647 # ~root/.config/guix/current/bin/guix-daemon \
648 --build-users-group=guixbuild
652 Make the @command{guix} command available to other users on the machine,
656 # mkdir -p /usr/local/bin
658 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
661 It is also a good idea to make the Info version of this manual available
665 # mkdir -p /usr/local/share/info
666 # cd /usr/local/share/info
667 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
671 That way, assuming @file{/usr/local/share/info} is in the search path,
672 running @command{info guix} will open this manual (@pxref{Other Info
673 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
677 @cindex substitutes, authorization thereof
678 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
679 (@pxref{Substitutes}), authorize them:
682 # guix archive --authorize < \
683 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
687 Each user may need to perform a few additional steps to make their Guix
688 environment ready for use, @pxref{Application Setup}.
691 Voilà, the installation is complete!
693 You can confirm that Guix is working by installing a sample package into
700 The binary installation tarball can be (re)produced and verified simply
701 by running the following command in the Guix source tree:
704 make guix-binary.@var{system}.tar.xz
708 ...@: which, in turn, runs:
711 guix pack -s @var{system} --localstatedir \
712 --profile-name=current-guix guix
715 @xref{Invoking guix pack}, for more info on this handy tool.
718 @section Requirements
720 This section lists requirements when building Guix from source. The
721 build procedure for Guix is the same as for other GNU software, and is
722 not covered here. Please see the files @file{README} and @file{INSTALL}
723 in the Guix source tree for additional details.
725 @cindex official website
726 GNU Guix is available for download from its website at
727 @url{https://www.gnu.org/software/guix/}.
729 GNU Guix depends on the following packages:
732 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 2.2.x;
733 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
736 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
737 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
738 Guile,, gnutls-guile, GnuTLS-Guile});
740 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
743 @c FIXME: Specify a version number once a release has been made.
744 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
746 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON};
747 @item @url{https://zlib.net, zlib};
748 @item @url{https://www.gnu.org/software/make/, GNU Make}.
751 The following dependencies are optional:
755 @c Note: We need at least 0.10.2 for 'channel-send-eof'.
756 Support for build offloading (@pxref{Daemon Offload Setup}) and
757 @command{guix copy} (@pxref{Invoking guix copy}) depends on
758 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
759 version 0.10.2 or later.
762 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
763 substitutes can be used and @command{guix publish} can compress substitutes
767 When @url{http://www.bzip.org, libbz2} is available,
768 @command{guix-daemon} can use it to compress build logs.
771 Unless @code{--disable-daemon} was passed to @command{configure}, the
772 following packages are also needed:
775 @item @url{https://gnupg.org/, GNU libgcrypt};
776 @item @url{https://sqlite.org, SQLite 3};
777 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
781 @cindex state directory
782 When configuring Guix on a system that already has a Guix installation,
783 be sure to specify the same state directory as the existing installation
784 using the @code{--localstatedir} option of the @command{configure}
785 script (@pxref{Directory Variables, @code{localstatedir},, standards,
786 GNU Coding Standards}). The @command{configure} script protects against
787 unintended misconfiguration of @var{localstatedir} so you do not
788 inadvertently corrupt your store (@pxref{The Store}).
790 @cindex Nix, compatibility
791 When a working installation of @url{https://nixos.org/nix/, the Nix package
792 manager} is available, you
793 can instead configure Guix with @code{--disable-daemon}. In that case,
794 Nix replaces the three dependencies above.
796 Guix is compatible with Nix, so it is possible to share the same store
797 between both. To do so, you must pass @command{configure} not only the
798 same @code{--with-store-dir} value, but also the same
799 @code{--localstatedir} value. The latter is essential because it
800 specifies where the database that stores metadata about the store is
801 located, among other things. The default values for Nix are
802 @code{--with-store-dir=/nix/store} and @code{--localstatedir=/nix/var}.
803 Note that @code{--disable-daemon} is not required if
804 your goal is to share the store with Nix.
806 @node Running the Test Suite
807 @section Running the Test Suite
810 After a successful @command{configure} and @code{make} run, it is a good
811 idea to run the test suite. It can help catch issues with the setup or
812 environment, or bugs in Guix itself---and really, reporting test
813 failures is a good way to help improve the software. To run the test
820 Test cases can run in parallel: you can use the @code{-j} option of
821 GNU@tie{}make to speed things up. The first run may take a few minutes
822 on a recent machine; subsequent runs will be faster because the store
823 that is created for test purposes will already have various things in
826 It is also possible to run a subset of the tests by defining the
827 @code{TESTS} makefile variable as in this example:
830 make check TESTS="tests/store.scm tests/cpio.scm"
833 By default, tests results are displayed at a file level. In order to
834 see the details of every individual test cases, it is possible to define
835 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
838 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
841 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
842 @file{test-suite.log} file. Please specify the Guix version being used
843 as well as version numbers of the dependencies (@pxref{Requirements}) in
846 Guix also comes with a whole-system test suite that tests complete
847 Guix System instances. It can only run on systems where
848 Guix is already installed, using:
855 or, again, by defining @code{TESTS} to select a subset of tests to run:
858 make check-system TESTS="basic mcron"
861 These system tests are defined in the @code{(gnu tests @dots{})}
862 modules. They work by running the operating systems under test with
863 lightweight instrumentation in a virtual machine (VM). They can be
864 computationally intensive or rather cheap, depending on whether
865 substitutes are available for their dependencies (@pxref{Substitutes}).
866 Some of them require a lot of storage space to hold VM images.
868 Again in case of test failures, please send @email{bug-guix@@gnu.org}
871 @node Setting Up the Daemon
872 @section Setting Up the Daemon
875 Operations such as building a package or running the garbage collector
876 are all performed by a specialized process, the @dfn{build daemon}, on
877 behalf of clients. Only the daemon may access the store and its
878 associated database. Thus, any operation that manipulates the store
879 goes through the daemon. For instance, command-line tools such as
880 @command{guix package} and @command{guix build} communicate with the
881 daemon (@i{via} remote procedure calls) to instruct it what to do.
883 The following sections explain how to prepare the build daemon's
884 environment. See also @ref{Substitutes}, for information on how to allow
885 the daemon to download pre-built binaries.
888 * Build Environment Setup:: Preparing the isolated build environment.
889 * Daemon Offload Setup:: Offloading builds to remote machines.
890 * SELinux Support:: Using an SELinux policy for the daemon.
893 @node Build Environment Setup
894 @subsection Build Environment Setup
896 @cindex build environment
897 In a standard multi-user setup, Guix and its daemon---the
898 @command{guix-daemon} program---are installed by the system
899 administrator; @file{/gnu/store} is owned by @code{root} and
900 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
901 Guix tools to build packages or otherwise access the store, and the
902 daemon will do it on their behalf, ensuring that the store is kept in a
903 consistent state, and allowing built packages to be shared among users.
906 When @command{guix-daemon} runs as @code{root}, you may not want package
907 build processes themselves to run as @code{root} too, for obvious
908 security reasons. To avoid that, a special pool of @dfn{build users}
909 should be created for use by build processes started by the daemon.
910 These build users need not have a shell and a home directory: they will
911 just be used when the daemon drops @code{root} privileges in build
912 processes. Having several such users allows the daemon to launch
913 distinct build processes under separate UIDs, which guarantees that they
914 do not interfere with each other---an essential feature since builds are
915 regarded as pure functions (@pxref{Introduction}).
917 On a GNU/Linux system, a build user pool may be created like this (using
918 Bash syntax and the @code{shadow} commands):
920 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
921 @c for why `-G' is needed.
923 # groupadd --system guixbuild
924 # for i in `seq -w 1 10`;
926 useradd -g guixbuild -G guixbuild \
927 -d /var/empty -s `which nologin` \
928 -c "Guix build user $i" --system \
934 The number of build users determines how many build jobs may run in
935 parallel, as specified by the @option{--max-jobs} option
936 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
937 @command{guix system vm} and related commands, you may need to add the
938 build users to the @code{kvm} group so they can access @file{/dev/kvm},
939 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
940 (@pxref{Invoking guix system}).
942 The @code{guix-daemon} program may then be run as @code{root} with the
943 following command@footnote{If your machine uses the systemd init system,
944 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
945 file in @file{/etc/systemd/system} will ensure that
946 @command{guix-daemon} is automatically started. Similarly, if your
947 machine uses the Upstart init system, drop the
948 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
949 file in @file{/etc/init}.}:
952 # guix-daemon --build-users-group=guixbuild
957 This way, the daemon starts build processes in a chroot, under one of
958 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
959 environment contains nothing but:
961 @c Keep this list in sync with libstore/build.cc! -----------------------
964 a minimal @code{/dev} directory, created mostly independently from the
965 host @code{/dev}@footnote{``Mostly'', because while the set of files
966 that appear in the chroot's @code{/dev} is fixed, most of these files
967 can only be created if the host has them.};
970 the @code{/proc} directory; it only shows the processes of the container
971 since a separate PID name space is used;
974 @file{/etc/passwd} with an entry for the current user and an entry for
978 @file{/etc/group} with an entry for the user's group;
981 @file{/etc/hosts} with an entry that maps @code{localhost} to
985 a writable @file{/tmp} directory.
988 You can influence the directory where the daemon stores build trees
989 @i{via} the @code{TMPDIR} environment variable. However, the build tree
990 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
991 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
992 This way, the value of @code{TMPDIR} does not leak inside build
993 environments, which avoids discrepancies in cases where build processes
994 capture the name of their build tree.
997 The daemon also honors the @code{http_proxy} environment variable for
998 HTTP downloads it performs, be it for fixed-output derivations
999 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1001 If you are installing Guix as an unprivileged user, it is still possible
1002 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1003 However, build processes will not be isolated from one another, and not
1004 from the rest of the system. Thus, build processes may interfere with
1005 each other, and may access programs, libraries, and other files
1006 available on the system---making it much harder to view them as
1007 @emph{pure} functions.
1010 @node Daemon Offload Setup
1011 @subsection Using the Offload Facility
1015 When desired, the build daemon can @dfn{offload} derivation builds to
1016 other machines running Guix, using the @code{offload} @dfn{build
1017 hook}@footnote{This feature is available only when
1018 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1019 present.}. When that
1020 feature is enabled, a list of user-specified build machines is read from
1021 @file{/etc/guix/machines.scm}; every time a build is requested, for
1022 instance via @code{guix build}, the daemon attempts to offload it to one
1023 of the machines that satisfy the constraints of the derivation, in
1024 particular its system type---e.g., @file{x86_64-linux}. Missing
1025 prerequisites for the build are copied over SSH to the target machine,
1026 which then proceeds with the build; upon success the output(s) of the
1027 build are copied back to the initial machine.
1029 The @file{/etc/guix/machines.scm} file typically looks like this:
1032 (list (build-machine
1033 (name "eightysix.example.org")
1034 (system "x86_64-linux")
1035 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1037 (speed 2.)) ;incredibly fast!
1040 (name "meeps.example.org")
1041 (system "mips64el-linux")
1042 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1045 (string-append (getenv "HOME")
1046 "/.ssh/identity-for-guix"))))
1050 In the example above we specify a list of two build machines, one for
1051 the @code{x86_64} architecture and one for the @code{mips64el}
1054 In fact, this file is---not surprisingly!---a Scheme file that is
1055 evaluated when the @code{offload} hook is started. Its return value
1056 must be a list of @code{build-machine} objects. While this example
1057 shows a fixed list of build machines, one could imagine, say, using
1058 DNS-SD to return a list of potential build machines discovered in the
1059 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1060 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1063 @deftp {Data Type} build-machine
1064 This data type represents build machines to which the daemon may offload
1065 builds. The important fields are:
1070 The host name of the remote machine.
1073 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1076 The user account to use when connecting to the remote machine over SSH.
1077 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1078 allow non-interactive logins.
1081 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1082 This is used to authenticate the machine when we connect to it. It is a
1083 long string that looks like this:
1086 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1089 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1090 key can be found in a file such as
1091 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1093 If the machine is running the SSH daemon of GNU@tie{}lsh,
1094 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1095 similar file. It can be converted to the OpenSSH format using
1096 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1099 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1100 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1105 A number of optional fields may be specified:
1109 @item @code{port} (default: @code{22})
1110 Port number of SSH server on the machine.
1112 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1113 The SSH private key file to use when connecting to the machine, in
1114 OpenSSH format. This key must not be protected with a passphrase.
1116 Note that the default value is the private key @emph{of the root
1117 account}. Make sure it exists if you use the default.
1119 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1120 @itemx @code{compression-level} (default: @code{3})
1121 The SSH-level compression methods and compression level requested.
1123 Note that offloading relies on SSH compression to reduce bandwidth usage
1124 when transferring files to and from build machines.
1126 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1127 File name of the Unix-domain socket @command{guix-daemon} is listening
1130 @item @code{parallel-builds} (default: @code{1})
1131 The number of builds that may run in parallel on the machine.
1133 @item @code{speed} (default: @code{1.0})
1134 A ``relative speed factor''. The offload scheduler will tend to prefer
1135 machines with a higher speed factor.
1137 @item @code{features} (default: @code{'()})
1138 A list of strings denoting specific features supported by the machine.
1139 An example is @code{"kvm"} for machines that have the KVM Linux modules
1140 and corresponding hardware support. Derivations can request features by
1141 name, and they will be scheduled on matching build machines.
1146 The @command{guix} command must be in the search path on the build
1147 machines. You can check whether this is the case by running:
1150 ssh build-machine guix repl --version
1153 There is one last thing to do once @file{machines.scm} is in place. As
1154 explained above, when offloading, files are transferred back and forth
1155 between the machine stores. For this to work, you first need to
1156 generate a key pair on each machine to allow the daemon to export signed
1157 archives of files from the store (@pxref{Invoking guix archive}):
1160 # guix archive --generate-key
1164 Each build machine must authorize the key of the master machine so that
1165 it accepts store items it receives from the master:
1168 # guix archive --authorize < master-public-key.txt
1172 Likewise, the master machine must authorize the key of each build machine.
1174 All the fuss with keys is here to express pairwise mutual trust
1175 relations between the master and the build machines. Concretely, when
1176 the master receives files from a build machine (and @i{vice versa}), its
1177 build daemon can make sure they are genuine, have not been tampered
1178 with, and that they are signed by an authorized key.
1180 @cindex offload test
1181 To test whether your setup is operational, run this command on the
1188 This will attempt to connect to each of the build machines specified in
1189 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1190 available on each machine, attempt to export to the machine and import
1191 from it, and report any error in the process.
1193 If you want to test a different machine file, just specify it on the
1197 # guix offload test machines-qualif.scm
1200 Last, you can test the subset of the machines whose name matches a
1201 regular expression like this:
1204 # guix offload test machines.scm '\.gnu\.org$'
1207 @cindex offload status
1208 To display the current load of all build hosts, run this command on the
1212 # guix offload status
1216 @node SELinux Support
1217 @subsection SELinux Support
1219 @cindex SELinux, daemon policy
1220 @cindex mandatory access control, SELinux
1221 @cindex security, guix-daemon
1222 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1223 can be installed on a system where SELinux is enabled, in order to label
1224 Guix files and to specify the expected behavior of the daemon. Since
1225 Guix System does not provide an SELinux base policy, the daemon policy cannot
1226 be used on Guix System.
1228 @subsubsection Installing the SELinux policy
1229 @cindex SELinux, policy installation
1230 To install the policy run this command as root:
1233 semodule -i etc/guix-daemon.cil
1236 Then relabel the file system with @code{restorecon} or by a different
1237 mechanism provided by your system.
1239 Once the policy is installed, the file system has been relabeled, and
1240 the daemon has been restarted, it should be running in the
1241 @code{guix_daemon_t} context. You can confirm this with the following
1245 ps -Zax | grep guix-daemon
1248 Monitor the SELinux log files as you run a command like @code{guix build
1249 hello} to convince yourself that SELinux permits all necessary
1252 @subsubsection Limitations
1253 @cindex SELinux, limitations
1255 This policy is not perfect. Here is a list of limitations or quirks
1256 that should be considered when deploying the provided SELinux policy for
1261 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1262 operations involve contexts that have anything to do with
1263 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1264 but it would be preferrable to define socket rules for only this label.
1267 @code{guix gc} cannot access arbitrary links to profiles. By design,
1268 the file label of the destination of a symlink is independent of the
1269 file label of the link itself. Although all profiles under
1270 $localstatedir are labelled, the links to these profiles inherit the
1271 label of the directory they are in. For links in the user’s home
1272 directory this will be @code{user_home_t}. But for links from the root
1273 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1274 directory, etc, this won’t work. @code{guix gc} would be prevented from
1275 reading and following these links.
1278 The daemon’s feature to listen for TCP connections might no longer work.
1279 This might require extra rules, because SELinux treats network sockets
1280 differently from files.
1283 Currently all files with a name matching the regular expression
1284 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1285 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1286 that name in any profile would be permitted to run in the
1287 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1288 build a package that provides this executable and convince a user to
1289 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1290 At that point SELinux could not prevent it from accessing files that are
1291 allowed for processes in that domain.
1293 We could generate a much more restrictive policy at installation time,
1294 so that only the @emph{exact} file name of the currently installed
1295 @code{guix-daemon} executable would be labelled with
1296 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1297 The downside is that root would have to install or upgrade the policy at
1298 installation time whenever the Guix package that provides the
1299 effectively running @code{guix-daemon} executable is upgraded.
1302 @node Invoking guix-daemon
1303 @section Invoking @command{guix-daemon}
1305 The @command{guix-daemon} program implements all the functionality to
1306 access the store. This includes launching build processes, running the
1307 garbage collector, querying the availability of a build result, etc. It
1308 is normally run as @code{root} like this:
1311 # guix-daemon --build-users-group=guixbuild
1315 For details on how to set it up, @pxref{Setting Up the Daemon}.
1318 @cindex container, build environment
1319 @cindex build environment
1320 @cindex reproducible builds
1321 By default, @command{guix-daemon} launches build processes under
1322 different UIDs, taken from the build group specified with
1323 @code{--build-users-group}. In addition, each build process is run in a
1324 chroot environment that only contains the subset of the store that the
1325 build process depends on, as specified by its derivation
1326 (@pxref{Programming Interface, derivation}), plus a set of specific
1327 system directories. By default, the latter contains @file{/dev} and
1328 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1329 @dfn{container}: in addition to having its own file system tree, it has
1330 a separate mount name space, its own PID name space, network name space,
1331 etc. This helps achieve reproducible builds (@pxref{Features}).
1333 When the daemon performs a build on behalf of the user, it creates a
1334 build directory under @file{/tmp} or under the directory specified by
1335 its @code{TMPDIR} environment variable. This directory is shared with
1336 the container for the duration of the build, though within the container,
1337 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1339 The build directory is automatically deleted upon completion, unless the
1340 build failed and the client specified @option{--keep-failed}
1341 (@pxref{Invoking guix build, @option{--keep-failed}}).
1343 The daemon listens for connections and spawns one sub-process for each session
1344 started by a client (one of the @command{guix} sub-commands.) The
1345 @command{guix processes} command allows you to get an overview of the activity
1346 on your system by viewing each of the active sessions and clients.
1347 @xref{Invoking guix processes}, for more information.
1349 The following command-line options are supported:
1352 @item --build-users-group=@var{group}
1353 Take users from @var{group} to run build processes (@pxref{Setting Up
1354 the Daemon, build users}).
1356 @item --no-substitutes
1358 Do not use substitutes for build products. That is, always build things
1359 locally instead of allowing downloads of pre-built binaries
1360 (@pxref{Substitutes}).
1362 When the daemon runs with @code{--no-substitutes}, clients can still
1363 explicitly enable substitution @i{via} the @code{set-build-options}
1364 remote procedure call (@pxref{The Store}).
1366 @item --substitute-urls=@var{urls}
1367 @anchor{daemon-substitute-urls}
1368 Consider @var{urls} the default whitespace-separated list of substitute
1369 source URLs. When this option is omitted,
1370 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1372 This means that substitutes may be downloaded from @var{urls}, as long
1373 as they are signed by a trusted signature (@pxref{Substitutes}).
1376 @item --no-build-hook
1377 Do not use the @dfn{build hook}.
1379 The build hook is a helper program that the daemon can start and to
1380 which it submits build requests. This mechanism is used to offload
1381 builds to other machines (@pxref{Daemon Offload Setup}).
1383 @item --cache-failures
1384 Cache build failures. By default, only successful builds are cached.
1386 When this option is used, @command{guix gc --list-failures} can be used
1387 to query the set of store items marked as failed; @command{guix gc
1388 --clear-failures} removes store items from the set of cached failures.
1389 @xref{Invoking guix gc}.
1391 @item --cores=@var{n}
1393 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1396 The default value is @code{0}, but it may be overridden by clients, such
1397 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1400 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1401 in the build process, which can then use it to exploit internal
1402 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1404 @item --max-jobs=@var{n}
1406 Allow at most @var{n} build jobs in parallel. The default value is
1407 @code{1}. Setting it to @code{0} means that no builds will be performed
1408 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1409 Setup}), or simply fail.
1411 @item --max-silent-time=@var{seconds}
1412 When the build or substitution process remains silent for more than
1413 @var{seconds}, terminate it and report a build failure.
1415 The default value is @code{0}, which disables the timeout.
1417 The value specified here can be overridden by clients (@pxref{Common
1418 Build Options, @code{--max-silent-time}}).
1420 @item --timeout=@var{seconds}
1421 Likewise, when the build or substitution process lasts for more than
1422 @var{seconds}, terminate it and report a build failure.
1424 The default value is @code{0}, which disables the timeout.
1426 The value specified here can be overridden by clients (@pxref{Common
1427 Build Options, @code{--timeout}}).
1429 @item --rounds=@var{N}
1430 Build each derivation @var{n} times in a row, and raise an error if
1431 consecutive build results are not bit-for-bit identical. Note that this
1432 setting can be overridden by clients such as @command{guix build}
1433 (@pxref{Invoking guix build}).
1435 When used in conjunction with @option{--keep-failed}, the differing
1436 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1437 This makes it easy to look for differences between the two results.
1440 Produce debugging output.
1442 This is useful to debug daemon start-up issues, but then it may be
1443 overridden by clients, for example the @code{--verbosity} option of
1444 @command{guix build} (@pxref{Invoking guix build}).
1446 @item --chroot-directory=@var{dir}
1447 Add @var{dir} to the build chroot.
1449 Doing this may change the result of build processes---for instance if
1450 they use optional dependencies found in @var{dir} when it is available,
1451 and not otherwise. For that reason, it is not recommended to do so.
1452 Instead, make sure that each derivation declares all the inputs that it
1455 @item --disable-chroot
1456 Disable chroot builds.
1458 Using this option is not recommended since, again, it would allow build
1459 processes to gain access to undeclared dependencies. It is necessary,
1460 though, when @command{guix-daemon} is running under an unprivileged user
1463 @item --log-compression=@var{type}
1464 Compress build logs according to @var{type}, one of @code{gzip},
1465 @code{bzip2}, or @code{none}.
1467 Unless @code{--lose-logs} is used, all the build logs are kept in the
1468 @var{localstatedir}. To save space, the daemon automatically compresses
1469 them with bzip2 by default.
1471 @item --disable-deduplication
1472 @cindex deduplication
1473 Disable automatic file ``deduplication'' in the store.
1475 By default, files added to the store are automatically ``deduplicated'':
1476 if a newly added file is identical to another one found in the store,
1477 the daemon makes the new file a hard link to the other file. This can
1478 noticeably reduce disk usage, at the expense of slightly increased
1479 input/output load at the end of a build process. This option disables
1482 @item --gc-keep-outputs[=yes|no]
1483 Tell whether the garbage collector (GC) must keep outputs of live
1487 @cindex garbage collector roots
1488 When set to ``yes'', the GC will keep the outputs of any live derivation
1489 available in the store---the @code{.drv} files. The default is ``no'',
1490 meaning that derivation outputs are kept only if they are reachable from a GC
1491 root. @xref{Invoking guix gc}, for more on GC roots.
1493 @item --gc-keep-derivations[=yes|no]
1494 Tell whether the garbage collector (GC) must keep derivations
1495 corresponding to live outputs.
1497 When set to ``yes'', as is the case by default, the GC keeps
1498 derivations---i.e., @code{.drv} files---as long as at least one of their
1499 outputs is live. This allows users to keep track of the origins of
1500 items in their store. Setting it to ``no'' saves a bit of disk space.
1502 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1503 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1504 ``yes'' causes liveness to flow from derivations to outputs. When both are
1505 set to ``yes'', the effect is to keep all the build prerequisites (the
1506 sources, compiler, libraries, and other build-time tools) of live objects in
1507 the store, regardless of whether these prerequisites are reachable from a GC
1508 root. This is convenient for developers since it saves rebuilds or downloads.
1510 @item --impersonate-linux-2.6
1511 On Linux-based systems, impersonate Linux 2.6. This means that the
1512 kernel's @code{uname} system call will report 2.6 as the release number.
1514 This might be helpful to build programs that (usually wrongfully) depend
1515 on the kernel version number.
1518 Do not keep build logs. By default they are kept under
1519 @code{@var{localstatedir}/guix/log}.
1521 @item --system=@var{system}
1522 Assume @var{system} as the current system type. By default it is the
1523 architecture/kernel pair found at configure time, such as
1524 @code{x86_64-linux}.
1526 @item --listen=@var{endpoint}
1527 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1528 as the file name of a Unix-domain socket if it starts with
1529 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1530 host name or host name and port to listen to. Here are a few examples:
1533 @item --listen=/gnu/var/daemon
1534 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1535 creating it if needed.
1537 @item --listen=localhost
1538 @cindex daemon, remote access
1539 @cindex remote access to the daemon
1540 @cindex daemon, cluster setup
1541 @cindex clusters, daemon setup
1542 Listen for TCP connections on the network interface corresponding to
1543 @code{localhost}, on port 44146.
1545 @item --listen=128.0.0.42:1234
1546 Listen for TCP connections on the network interface corresponding to
1547 @code{128.0.0.42}, on port 1234.
1550 This option can be repeated multiple times, in which case
1551 @command{guix-daemon} accepts connections on all the specified
1552 endpoints. Users can tell client commands what endpoint to connect to
1553 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1554 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1557 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1558 @code{--listen=@var{host}} is suitable on local networks, such as
1559 clusters, where only trusted nodes may connect to the build daemon. In
1560 other cases where remote access to the daemon is needed, we recommend
1561 using Unix-domain sockets along with SSH.
1564 When @code{--listen} is omitted, @command{guix-daemon} listens for
1565 connections on the Unix-domain socket located at
1566 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1570 @node Application Setup
1571 @section Application Setup
1573 @cindex foreign distro
1574 When using Guix on top of GNU/Linux distribution other than Guix System---a
1575 so-called @dfn{foreign distro}---a few additional steps are needed to
1576 get everything in place. Here are some of them.
1580 @anchor{locales-and-locpath}
1581 @cindex locales, when not on Guix System
1583 @vindex GUIX_LOCPATH
1584 Packages installed @i{via} Guix will not use the locale data of the
1585 host system. Instead, you must first install one of the locale packages
1586 available with Guix and then define the @code{GUIX_LOCPATH} environment
1590 $ guix install glibc-locales
1591 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1594 Note that the @code{glibc-locales} package contains data for all the
1595 locales supported by the GNU@tie{}libc and weighs in at around
1596 110@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1597 limited to a few UTF-8 locales.
1599 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1600 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1601 Manual}). There are two important differences though:
1605 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1606 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1607 to make sure the programs of the foreign distro will not end up loading
1608 incompatible locale data.
1611 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1612 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1613 should your Guix profile contain a mixture of programs linked against
1614 different libc version, each libc version will only try to load locale
1615 data in the right format.
1618 This is important because the locale data format used by different libc
1619 versions may be incompatible.
1621 @subsection Name Service Switch
1623 @cindex name service switch, glibc
1624 @cindex NSS (name service switch), glibc
1625 @cindex nscd (name service caching daemon)
1626 @cindex name service caching daemon (nscd)
1627 When using Guix on a foreign distro, we @emph{strongly recommend} that
1628 the system run the GNU C library's @dfn{name service cache daemon},
1629 @command{nscd}, which should be listening on the
1630 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1631 installed with Guix may fail to look up host names or user accounts, or
1632 may even crash. The next paragraphs explain why.
1634 @cindex @file{nsswitch.conf}
1635 The GNU C library implements a @dfn{name service switch} (NSS), which is
1636 an extensible mechanism for ``name lookups'' in general: host name
1637 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1638 The GNU C Library Reference Manual}).
1640 @cindex Network information service (NIS)
1641 @cindex NIS (Network information service)
1642 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1643 lookup implementations: for example, the @code{nss-mdns} plugin allow
1644 resolution of @code{.local} host names, the @code{nis} plugin allows
1645 user account lookup using the Network information service (NIS), and so
1646 on. These extra ``lookup services'' are configured system-wide in
1647 @file{/etc/nsswitch.conf}, and all the programs running on the system
1648 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1651 When they perform a name lookup---for instance by calling the
1652 @code{getaddrinfo} function in C---applications first try to connect to
1653 the nscd; on success, nscd performs name lookups on their behalf. If
1654 the nscd is not running, then they perform the name lookup by
1655 themselves, by loading the name lookup services into their own address
1656 space and running it. These name lookup services---the
1657 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1658 the host system's C library, rather than from the C library the
1659 application is linked against (the C library coming from Guix).
1661 And this is where the problem is: if your application is linked against
1662 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1663 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1664 likely crash or have its name lookups fail unexpectedly.
1666 Running @command{nscd} on the system, among other advantages, eliminates
1667 this binary incompatibility problem because those @code{libnss_*.so}
1668 files are loaded in the @command{nscd} process, not in applications
1671 @subsection X11 Fonts
1674 The majority of graphical applications use Fontconfig to locate and
1675 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1676 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1677 by default. Thus, to allow graphical applications installed with Guix
1678 to display fonts, you have to install fonts with Guix as well.
1679 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1680 @code{font-gnu-freefont-ttf}.
1682 To display text written in Chinese languages, Japanese, or Korean in
1683 graphical applications, consider installing
1684 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1685 has multiple outputs, one per language family (@pxref{Packages with
1686 Multiple Outputs}). For instance, the following command installs fonts
1687 for Chinese languages:
1690 guix install font-adobe-source-han-sans:cn
1693 @cindex @code{xterm}
1694 Older programs such as @command{xterm} do not use Fontconfig and instead
1695 rely on server-side font rendering. Such programs require to specify a
1696 full name of a font using XLFD (X Logical Font Description), like this:
1699 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1702 To be able to use such full names for the TrueType fonts installed in
1703 your Guix profile, you need to extend the font path of the X server:
1705 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1706 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1708 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1711 @cindex @code{xlsfonts}
1712 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1713 to make sure your TrueType fonts are listed there.
1715 @cindex @code{fc-cache}
1717 After installing fonts you may have to refresh the font cache to use
1718 them in applications. The same applies when applications installed via
1719 Guix do not seem to find fonts. To force rebuilding of the font cache
1720 run @code{fc-cache -f}. The @code{fc-cache} command is provided by the
1721 @code{fontconfig} package.
1723 @subsection X.509 Certificates
1725 @cindex @code{nss-certs}
1726 The @code{nss-certs} package provides X.509 certificates, which allow
1727 programs to authenticate Web servers accessed over HTTPS.
1729 When using Guix on a foreign distro, you can install this package and
1730 define the relevant environment variables so that packages know where to
1731 look for certificates. @xref{X.509 Certificates}, for detailed
1734 @subsection Emacs Packages
1736 @cindex @code{emacs}
1737 When you install Emacs packages with Guix, the elisp files may be placed
1738 either in @file{$HOME/.guix-profile/share/emacs/site-lisp/} or in
1740 @file{$HOME/.guix-profile/share/emacs/site-lisp/guix.d/}. The latter
1741 directory exists because potentially there may exist thousands of Emacs
1742 packages and storing all their files in a single directory may not be
1743 reliable (because of name conflicts). So we think using a separate
1744 directory for each package is a good idea. It is very similar to how
1745 the Emacs package system organizes the file structure (@pxref{Package
1746 Files,,, emacs, The GNU Emacs Manual}).
1748 By default, Emacs (installed with Guix) ``knows'' where these packages
1749 are placed, so you do not need to perform any configuration. If, for
1750 some reason, you want to avoid auto-loading Emacs packages installed
1751 with Guix, you can do so by running Emacs with @code{--no-site-file}
1752 option (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1754 @subsection The GCC toolchain
1759 Guix offers individual compiler packages such as @code{gcc} but if you
1760 are in need of a complete toolchain for compiling and linking source
1761 code what you really want is the @code{gcc-toolchain} package. This
1762 package provides a complete GCC toolchain for C/C++ development,
1763 including GCC itself, the GNU C Library (headers and binaries, plus
1764 debugging symbols in the @code{debug} output), Binutils, and a linker
1767 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
1768 passed to the linker, add corresponding @code{-rpath} arguments, and
1769 invoke the actual linker with this new set of arguments. You can instruct the
1770 wrapper to refuse to link against libraries not in the store by setting the
1771 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
1775 @c *********************************************************************
1776 @node System Installation
1777 @chapter System Installation
1779 @cindex installing Guix System
1780 @cindex Guix System, installation
1781 This section explains how to install Guix System
1782 on a machine. Guix, as a package manager, can
1783 also be installed on top of a running GNU/Linux system,
1784 @pxref{Installation}.
1788 @c This paragraph is for people reading this from tty2 of the
1789 @c installation image.
1790 You are reading this documentation with an Info reader. For details on
1791 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1792 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1793 Info}. Hit @kbd{l} afterwards to come back here.
1795 Alternately, run @command{info info} in another tty to keep the manual
1801 * Limitations:: What you can expect.
1802 * Hardware Considerations:: Supported hardware.
1803 * USB Stick and DVD Installation:: Preparing the installation medium.
1804 * Preparing for Installation:: Networking, partitioning, etc.
1805 * Guided Graphical Installation:: Easy graphical installation.
1806 * Manual Installation:: Manual installation for wizards.
1807 * After System Installation:: When installation succeeded.
1808 * Installing Guix in a VM:: Guix System playground.
1809 * Building the Installation Image:: How this comes to be.
1813 @section Limitations
1815 We consider Guix System to be ready for a wide range of ``desktop'' and server
1816 use cases. The reliability guarantees it provides---transactional upgrades
1817 and rollbacks, reproducibility---make it a solid foundation.
1819 Nevertheless, before you proceed with the installation, be aware of the
1820 following noteworthy limitations applicable to version @value{VERSION}:
1824 Support for the Logical Volume Manager (LVM) is missing.
1827 More and more system services are provided (@pxref{Services}), but some
1831 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1832 as well as a number of X11 window managers. However, KDE is currently
1836 More than a disclaimer, this is an invitation to report issues (and success
1837 stories!), and to join us in improving it. @xref{Contributing}, for more
1841 @node Hardware Considerations
1842 @section Hardware Considerations
1844 @cindex hardware support on Guix System
1845 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1846 builds around the kernel Linux-libre, which means that only hardware for
1847 which free software drivers and firmware exist is supported. Nowadays,
1848 a wide range of off-the-shelf hardware is supported on
1849 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1850 Ethernet controllers. Unfortunately, there are still areas where
1851 hardware vendors deny users control over their own computing, and such
1852 hardware is not supported on Guix System.
1854 @cindex WiFi, hardware support
1855 One of the main areas where free drivers or firmware are lacking is WiFi
1856 devices. WiFi devices known to work include those using Atheros chips
1857 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1858 driver, and those using Broadcom/AirForce chips (BCM43xx with
1859 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1860 Linux-libre driver. Free firmware exists for both and is available
1861 out-of-the-box on Guix System, as part of @code{%base-firmware}
1862 (@pxref{operating-system Reference, @code{firmware}}).
1864 @cindex RYF, Respects Your Freedom
1865 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1866 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1867 certification program for hardware products that respect your freedom
1868 and your privacy and ensure that you have control over your device. We
1869 encourage you to check the list of RYF-certified devices.
1871 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1872 web site. It contains a catalog of hardware devices with information
1873 about their support in GNU/Linux.
1876 @node USB Stick and DVD Installation
1877 @section USB Stick and DVD Installation
1879 An ISO-9660 installation image that can be written to a USB stick or
1880 burnt to a DVD can be downloaded from
1881 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1882 where @var{system} is one of:
1886 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1889 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1892 @c start duplication of authentication part from ``Binary Installation''
1893 Make sure to download the associated @file{.sig} file and to verify the
1894 authenticity of the image against it, along these lines:
1897 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1898 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1901 If that command fails because you do not have the required public key,
1902 then run this command to import it:
1905 $ gpg --keyserver @value{KEY-SERVER} \
1906 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
1910 and rerun the @code{gpg --verify} command.
1913 This image contains the tools necessary for an installation.
1914 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1916 @unnumberedsubsec Copying to a USB Stick
1918 To copy the image to a USB stick, follow these steps:
1922 Decompress the image using the @command{xz} command:
1925 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1929 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1930 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1931 copy the image with:
1934 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1938 Access to @file{/dev/sdX} usually requires root privileges.
1941 @unnumberedsubsec Burning on a DVD
1943 To copy the image to a DVD, follow these steps:
1947 Decompress the image using the @command{xz} command:
1950 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1954 Insert a blank DVD into your machine, and determine
1955 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
1956 copy the image with:
1959 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
1962 Access to @file{/dev/srX} usually requires root privileges.
1965 @unnumberedsubsec Booting
1967 Once this is done, you should be able to reboot the system and boot from
1968 the USB stick or DVD. The latter usually requires you to get in the
1969 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
1971 @xref{Installing Guix in a VM}, if, instead, you would like to install
1972 Guix System in a virtual machine (VM).
1975 @node Preparing for Installation
1976 @section Preparing for Installation
1978 Once you have booted, you can use the guided graphical installer, which makes
1979 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
1980 if you are already familiar with GNU/Linux and if you want more control than
1981 what the graphical installer provides, you can choose the ``manual''
1982 installation process (@pxref{Manual Installation}).
1984 The graphical installer is available on TTY1. You can obtain root shells on
1985 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
1986 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
1987 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
1988 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
1989 which allows you to select text with the left mouse button and to paste it
1990 with the middle button.
1993 Installation requires access to the Internet so that any missing
1994 dependencies of your system configuration can be downloaded. See the
1995 ``Networking'' section below.
1998 @node Guided Graphical Installation
1999 @section Guided Graphical Installation
2001 The graphical installer is a text-based user interface. It will guide you,
2002 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2004 The first dialog boxes allow you to set up the system as you use it during the
2005 installation: you can choose the language, keyboard layout, and set up
2006 networking, which will be used during the installation. The image below shows
2007 the networking dialog.
2009 @image{images/installer-network,5in,, networking setup with the graphical installer}
2011 Later steps allow you to partition your hard disk, as shown in the image
2012 below, to choose whether or not to use encrypted file systems, to enter the
2013 host name and root password, and to create an additional account, among other
2016 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2018 Note that, at any time, the installer allows you to exit the current
2019 installation step and resume at a previous step, as show in the image below.
2021 @image{images/installer-resume,5in,, resuming the installation process}
2023 Once you're done, the installer produces an operating system configuration and
2024 displays it (@pxref{Using the Configuration System}). At that point you can
2025 hit ``OK'' and installation will proceed. On success, you can reboot into the
2026 new system and enjoy. @xref{After System Installation}, for what's next!
2029 @node Manual Installation
2030 @section Manual Installation
2032 This section describes how you would ``manually'' install GNU@tie{}Guix System
2033 on your machine. This option requires familiarity with GNU/Linux, with the
2034 shell, and with common administration tools. If you think this is not for
2035 you, consider using the guided graphical installer (@pxref{Guided Graphical
2038 The installation system provides root shells on TTYs 3 to 6; press
2039 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2040 many common tools needed to install the system. But it is also a full-blown
2041 Guix System, which means that you can install additional packages, should you
2042 need it, using @command{guix package} (@pxref{Invoking guix package}).
2045 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2046 * Proceeding with the Installation:: Installing.
2049 @node Keyboard Layout and Networking and Partitioning
2050 @subsection Keyboard Layout, Networking, and Partitioning
2052 Before you can install the system, you may want to adjust the keyboard layout,
2053 set up networking, and partition your target hard disk. This section will
2054 guide you through this.
2056 @subsubsection Keyboard Layout
2058 @cindex keyboard layout
2059 The installation image uses the US qwerty keyboard layout. If you want
2060 to change it, you can use the @command{loadkeys} command. For example,
2061 the following command selects the Dvorak keyboard layout:
2067 See the files under @file{/run/current-system/profile/share/keymaps} for
2068 a list of available keyboard layouts. Run @command{man loadkeys} for
2071 @subsubsection Networking
2073 Run the following command to see what your network interfaces are called:
2080 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2086 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2087 Wired interfaces have a name starting with @samp{e}; for example, the
2088 interface corresponding to the first on-board Ethernet controller is
2089 called @samp{eno1}. Wireless interfaces have a name starting with
2090 @samp{w}, like @samp{w1p2s0}.
2093 @item Wired connection
2094 To configure a wired network run the following command, substituting
2095 @var{interface} with the name of the wired interface you want to use.
2098 ifconfig @var{interface} up
2101 @item Wireless connection
2104 To configure wireless networking, you can create a configuration file
2105 for the @command{wpa_supplicant} configuration tool (its location is not
2106 important) using one of the available text editors such as
2110 nano wpa_supplicant.conf
2113 As an example, the following stanza can go to this file and will work
2114 for many wireless networks, provided you give the actual SSID and
2115 passphrase for the network you are connecting to:
2119 ssid="@var{my-ssid}"
2121 psk="the network's secret passphrase"
2125 Start the wireless service and run it in the background with the
2126 following command (substitute @var{interface} with the name of the
2127 network interface you want to use):
2130 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2133 Run @command{man wpa_supplicant} for more information.
2137 At this point, you need to acquire an IP address. On a network where IP
2138 addresses are automatically assigned @i{via} DHCP, you can run:
2141 dhclient -v @var{interface}
2144 Try to ping a server to see if networking is up and running:
2150 Setting up network access is almost always a requirement because the
2151 image does not contain all the software and tools that may be needed.
2153 @cindex installing over SSH
2154 If you want to, you can continue the installation remotely by starting
2158 herd start ssh-daemon
2161 Make sure to either set a password with @command{passwd}, or configure
2162 OpenSSH public key authentication before logging in.
2164 @subsubsection Disk Partitioning
2166 Unless this has already been done, the next step is to partition, and
2167 then format the target partition(s).
2169 The installation image includes several partitioning tools, including
2170 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2171 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2172 the partition layout you want:
2178 If your disk uses the GUID Partition Table (GPT) format and you plan to
2179 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2180 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2183 @cindex EFI, installation
2184 @cindex UEFI, installation
2185 @cindex ESP, EFI system partition
2186 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2187 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2188 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2191 parted /dev/sda set 1 esp on
2195 @vindex grub-bootloader
2196 @vindex grub-efi-bootloader
2197 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2198 @file{/sys/firmware/efi} exists in the installation image, then you should
2199 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2200 Otherwise you should use the BIOS-based GRUB, known as
2201 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2205 Once you are done partitioning the target hard disk drive, you have to
2206 create a file system on the relevant partition(s)@footnote{Currently
2207 Guix System only supports ext4 and btrfs file systems. In particular, code
2208 that reads file system UUIDs and labels only works for these file system
2209 types.}. For the ESP, if you have one and assuming it is
2210 @file{/dev/sda1}, run:
2213 mkfs.fat -F32 /dev/sda1
2216 Preferably, assign file systems a label so that you can easily and
2217 reliably refer to them in @code{file-system} declarations (@pxref{File
2218 Systems}). This is typically done using the @code{-L} option of
2219 @command{mkfs.ext4} and related commands. So, assuming the target root
2220 partition lives at @file{/dev/sda2}, a file system with the label
2221 @code{my-root} can be created with:
2224 mkfs.ext4 -L my-root /dev/sda2
2227 @cindex encrypted disk
2228 If you are instead planning to encrypt the root partition, you can use
2229 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2230 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2231 @code{man cryptsetup}} for more information.) Assuming you want to
2232 store the root partition on @file{/dev/sda2}, the command sequence would
2233 be along these lines:
2236 cryptsetup luksFormat /dev/sda2
2237 cryptsetup open --type luks /dev/sda2 my-partition
2238 mkfs.ext4 -L my-root /dev/mapper/my-partition
2241 Once that is done, mount the target file system under @file{/mnt}
2242 with a command like (again, assuming @code{my-root} is the label of the
2246 mount LABEL=my-root /mnt
2249 Also mount any other file systems you would like to use on the target
2250 system relative to this path. If you have opted for @file{/boot/efi} as an
2251 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2252 found by @code{guix system init} afterwards.
2254 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2255 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2256 sure to initialize them with @command{mkswap}. Assuming you have one
2257 swap partition on @file{/dev/sda3}, you would run:
2264 Alternatively, you may use a swap file. For example, assuming that in
2265 the new system you want to use the file @file{/swapfile} as a swap file,
2266 you would run@footnote{This example will work for many types of file
2267 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2268 btrfs), the required steps may be different. For details, see the
2269 manual pages for @command{mkswap} and @command{swapon}.}:
2272 # This is 10 GiB of swap space. Adjust "count" to change the size.
2273 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2274 # For security, make the file readable and writable only by root.
2275 chmod 600 /mnt/swapfile
2276 mkswap /mnt/swapfile
2277 swapon /mnt/swapfile
2280 Note that if you have encrypted the root partition and created a swap
2281 file in its file system as described above, then the encryption also
2282 protects the swap file, just like any other file in that file system.
2284 @node Proceeding with the Installation
2285 @subsection Proceeding with the Installation
2287 With the target partitions ready and the target root mounted on
2288 @file{/mnt}, we're ready to go. First, run:
2291 herd start cow-store /mnt
2294 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2295 during the installation phase are written to the target disk on @file{/mnt}
2296 rather than kept in memory. This is necessary because the first phase of
2297 the @command{guix system init} command (see below) entails downloads or
2298 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2300 Next, you have to edit a file and
2301 provide the declaration of the operating system to be installed. To
2302 that end, the installation system comes with three text editors. We
2303 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2304 supports syntax highlighting and parentheses matching; other editors
2305 include GNU Zile (an Emacs clone), and
2306 nvi (a clone of the original BSD @command{vi} editor).
2307 We strongly recommend storing that file on the target root file system, say,
2308 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2309 configuration file once you have rebooted into the newly-installed system.
2311 @xref{Using the Configuration System}, for an overview of the
2312 configuration file. The example configurations discussed in that
2313 section are available under @file{/etc/configuration} in the
2314 installation image. Thus, to get started with a system configuration
2315 providing a graphical display server (a ``desktop'' system), you can run
2316 something along these lines:
2320 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2321 # nano /mnt/etc/config.scm
2324 You should pay attention to what your configuration file contains, and
2329 Make sure the @code{bootloader-configuration} form refers to the target
2330 you want to install GRUB on. It should mention @code{grub-bootloader} if
2331 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2332 for newer UEFI systems. For legacy systems, the @code{target} field
2333 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2334 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2335 currently mounted and a @code{file-system} entry is specified in your
2339 Be sure that your file system labels match the value of their respective
2340 @code{device} fields in your @code{file-system} configuration, assuming
2341 your @code{file-system} configuration uses the @code{file-system-label}
2342 procedure in its @code{device} field.
2345 If there are encrypted or RAID partitions, make sure to add a
2346 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2349 Once you are done preparing the configuration file, the new system must
2350 be initialized (remember that the target root file system is mounted
2354 guix system init /mnt/etc/config.scm /mnt
2358 This copies all the necessary files and installs GRUB on
2359 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2360 more information, @pxref{Invoking guix system}. This command may trigger
2361 downloads or builds of missing packages, which can take some time.
2363 Once that command has completed---and hopefully succeeded!---you can run
2364 @command{reboot} and boot into the new system. The @code{root} password
2365 in the new system is initially empty; other users' passwords need to be
2366 initialized by running the @command{passwd} command as @code{root},
2367 unless your configuration specifies otherwise
2368 (@pxref{user-account-password, user account passwords}).
2369 @xref{After System Installation}, for what's next!
2372 @node After System Installation
2373 @section After System Installation
2375 Success, you've now booted into Guix System! From then on, you can update the
2376 system whenever you want by running, say:
2380 sudo guix system reconfigure /etc/config.scm
2384 This builds a new system generation with the latest packages and services
2385 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2386 your system includes the latest security updates (@pxref{Security Updates}).
2388 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2390 @cindex sudo vs. @command{guix pull}
2391 Note that @command{sudo guix} runs your user's @command{guix} command and
2392 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2393 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2396 Join us on @code{#guix} on the Freenode IRC network or on
2397 @email{guix-devel@@gnu.org} to share your experience!
2400 @node Installing Guix in a VM
2401 @section Installing Guix in a Virtual Machine
2403 @cindex virtual machine, Guix System installation
2404 @cindex virtual private server (VPS)
2405 @cindex VPS (virtual private server)
2406 If you'd like to install Guix System in a virtual machine (VM) or on a
2407 virtual private server (VPS) rather than on your beloved machine, this
2410 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2411 disk image, follow these steps:
2415 First, retrieve and decompress the Guix system installation image as
2416 described previously (@pxref{USB Stick and DVD Installation}).
2419 Create a disk image that will hold the installed system. To make a
2420 qcow2-formatted disk image, use the @command{qemu-img} command:
2423 qemu-img create -f qcow2 guixsd.img 50G
2426 The resulting file will be much smaller than 50 GB (typically less than
2427 1 MB), but it will grow as the virtualized storage device is filled up.
2430 Boot the USB installation image in an VM:
2433 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2434 -net user -net nic,model=virtio -boot menu=on \
2435 -drive file=guix-system-install-@value{VERSION}.@var{system}.iso \
2436 -drive file=guixsd.img
2439 The ordering of the drives matters. @code{-enable-kvm} is optional, but
2440 significantly improves performance, @pxref{Running Guix in a VM}.
2442 In the VM console, quickly press the @kbd{F12} key to enter the boot
2443 menu. Then press the @kbd{2} key and the @kbd{RET} key to validate your
2447 You're now root in the VM, proceed with the installation process.
2448 @xref{Preparing for Installation}, and follow the instructions.
2451 Once installation is complete, you can boot the system that's on your
2452 @file{guixsd.img} image. @xref{Running Guix in a VM}, for how to do
2455 @node Building the Installation Image
2456 @section Building the Installation Image
2458 @cindex installation image
2459 The installation image described above was built using the @command{guix
2460 system} command, specifically:
2463 guix system disk-image --file-system-type=iso9660 \
2464 gnu/system/install.scm
2467 Have a look at @file{gnu/system/install.scm} in the source tree,
2468 and see also @ref{Invoking guix system} for more information
2469 about the installation image.
2471 @section Building the Installation Image for ARM Boards
2473 Many ARM boards require a specific variant of the
2474 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2476 If you build a disk image and the bootloader is not available otherwise
2477 (on another boot drive etc), it's advisable to build an image that
2478 includes the bootloader, specifically:
2481 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2484 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2485 board, a list of possible boards will be printed.
2487 @c *********************************************************************
2488 @node Package Management
2489 @chapter Package Management
2492 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2493 remove software packages, without having to know about their build
2494 procedures or dependencies. Guix also goes beyond this obvious set of
2497 This chapter describes the main features of Guix, as well as the
2498 package management tools it provides. Along with the command-line
2499 interface described below (@pxref{Invoking guix package, @code{guix
2500 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2501 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2502 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2506 guix install emacs-guix
2510 * Features:: How Guix will make your life brighter.
2511 * Invoking guix package:: Package installation, removal, etc.
2512 * Substitutes:: Downloading pre-built binaries.
2513 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2514 * Invoking guix gc:: Running the garbage collector.
2515 * Invoking guix pull:: Fetching the latest Guix and distribution.
2516 * Channels:: Customizing the package collection.
2517 * Inferiors:: Interacting with another revision of Guix.
2518 * Invoking guix describe:: Display information about your Guix revision.
2519 * Invoking guix archive:: Exporting and importing store files.
2525 When using Guix, each package ends up in the @dfn{package store}, in its
2526 own directory---something that resembles
2527 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2529 Instead of referring to these directories, users have their own
2530 @dfn{profile}, which points to the packages that they actually want to
2531 use. These profiles are stored within each user's home directory, at
2532 @code{$HOME/.guix-profile}.
2534 For example, @code{alice} installs GCC 4.7.2. As a result,
2535 @file{/home/alice/.guix-profile/bin/gcc} points to
2536 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2537 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2538 simply continues to point to
2539 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2540 coexist on the same system without any interference.
2542 The @command{guix package} command is the central tool to manage
2543 packages (@pxref{Invoking guix package}). It operates on the per-user
2544 profiles, and can be used @emph{with normal user privileges}.
2546 @cindex transactions
2547 The command provides the obvious install, remove, and upgrade
2548 operations. Each invocation is actually a @emph{transaction}: either
2549 the specified operation succeeds, or nothing happens. Thus, if the
2550 @command{guix package} process is terminated during the transaction,
2551 or if a power outage occurs during the transaction, then the user's
2552 profile remains in its previous state, and remains usable.
2554 In addition, any package transaction may be @emph{rolled back}. So, if,
2555 for example, an upgrade installs a new version of a package that turns
2556 out to have a serious bug, users may roll back to the previous instance
2557 of their profile, which was known to work well. Similarly, the global
2558 system configuration on Guix is subject to
2559 transactional upgrades and roll-back
2560 (@pxref{Using the Configuration System}).
2562 All packages in the package store may be @emph{garbage-collected}.
2563 Guix can determine which packages are still referenced by user
2564 profiles, and remove those that are provably no longer referenced
2565 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2566 generations of their profile so that the packages they refer to can be
2569 @cindex reproducibility
2570 @cindex reproducible builds
2571 Guix takes a @dfn{purely functional} approach to package
2572 management, as described in the introduction (@pxref{Introduction}).
2573 Each @file{/gnu/store} package directory name contains a hash of all the
2574 inputs that were used to build that package---compiler, libraries, build
2575 scripts, etc. This direct correspondence allows users to make sure a
2576 given package installation matches the current state of their
2577 distribution. It also helps maximize @dfn{build reproducibility}:
2578 thanks to the isolated build environments that are used, a given build
2579 is likely to yield bit-identical files when performed on different
2580 machines (@pxref{Invoking guix-daemon, container}).
2583 This foundation allows Guix to support @dfn{transparent binary/source
2584 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2585 available from an external source---a @dfn{substitute}, Guix just
2586 downloads it and unpacks it;
2587 otherwise, it builds the package from source, locally
2588 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2589 reproducible, users do not have to trust servers that provide
2590 substitutes: they can force a local build and @emph{challenge} providers
2591 (@pxref{Invoking guix challenge}).
2593 Control over the build environment is a feature that is also useful for
2594 developers. The @command{guix environment} command allows developers of
2595 a package to quickly set up the right development environment for their
2596 package, without having to manually install the dependencies of the
2597 package into their profile (@pxref{Invoking guix environment}).
2599 @cindex replication, of software environments
2600 @cindex provenance tracking, of software artifacts
2601 All of Guix and its package definitions is version-controlled, and
2602 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2603 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2604 Guix instance on a different machine or at a later point in time, which in
2605 turn allows you to @emph{replicate complete software environments}, while
2606 retaining precise @dfn{provenance tracking} of the software.
2608 @node Invoking guix package
2609 @section Invoking @command{guix package}
2611 @cindex installing packages
2612 @cindex removing packages
2613 @cindex package installation
2614 @cindex package removal
2615 The @command{guix package} command is the tool that allows users to
2616 install, upgrade, and remove packages, as well as rolling back to
2617 previous configurations. It operates only on the user's own profile,
2618 and works with normal user privileges (@pxref{Features}). Its syntax
2622 guix package @var{options}
2625 @cindex transactions
2626 Primarily, @var{options} specifies the operations to be performed during
2627 the transaction. Upon completion, a new profile is created, but
2628 previous @dfn{generations} of the profile remain available, should the user
2631 For example, to remove @code{lua} and install @code{guile} and
2632 @code{guile-cairo} in a single transaction:
2635 guix package -r lua -i guile guile-cairo
2638 @cindex aliases, for @command{guix package}
2639 For your convenience, we also provide the following aliases:
2643 @command{guix search} is an alias for @command{guix package -s},
2645 @command{guix install} is an alias for @command{guix package -i},
2647 @command{guix remove} is an alias for @command{guix package -r},
2649 and @command{guix upgrade} is an alias for @command{guix package -u}.
2652 These aliases are less expressive than @command{guix package} and provide
2653 fewer options, so in some cases you'll probably want to use @command{guix
2656 @command{guix package} also supports a @dfn{declarative approach}
2657 whereby the user specifies the exact set of packages to be available and
2658 passes it @i{via} the @option{--manifest} option
2659 (@pxref{profile-manifest, @option{--manifest}}).
2662 For each user, a symlink to the user's default profile is automatically
2663 created in @file{$HOME/.guix-profile}. This symlink always points to the
2664 current generation of the user's default profile. Thus, users can add
2665 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2666 variable, and so on.
2667 @cindex search paths
2668 If you are not using Guix System, consider adding the
2669 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2670 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2671 shells get all the right environment variable definitions:
2674 GUIX_PROFILE="$HOME/.guix-profile" ; \
2675 source "$HOME/.guix-profile/etc/profile"
2678 In a multi-user setup, user profiles are stored in a place registered as
2679 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2680 to (@pxref{Invoking guix gc}). That directory is normally
2681 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2682 @var{localstatedir} is the value passed to @code{configure} as
2683 @code{--localstatedir}, and @var{user} is the user name. The
2684 @file{per-user} directory is created when @command{guix-daemon} is
2685 started, and the @var{user} sub-directory is created by @command{guix
2688 The @var{options} can be among the following:
2692 @item --install=@var{package} @dots{}
2693 @itemx -i @var{package} @dots{}
2694 Install the specified @var{package}s.
2696 Each @var{package} may specify either a simple package name, such as
2697 @code{guile}, or a package name followed by an at-sign and version number,
2698 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2699 case, the newest version prefixed by @code{1.8} is selected.)
2701 If no version number is specified, the
2702 newest available version will be selected. In addition, @var{package}
2703 may contain a colon, followed by the name of one of the outputs of the
2704 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2705 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2706 name (and optionally version) are searched for among the GNU
2707 distribution modules (@pxref{Package Modules}).
2709 @cindex propagated inputs
2710 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2711 that automatically get installed along with the required package
2712 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2713 @code{package} objects}, for information about propagated inputs in
2714 package definitions).
2716 @anchor{package-cmd-propagated-inputs}
2717 An example is the GNU MPC library: its C header files refer to those of
2718 the GNU MPFR library, which in turn refer to those of the GMP library.
2719 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2720 in the profile; removing MPC also removes MPFR and GMP---unless they had
2721 also been explicitly installed by the user.
2723 Besides, packages sometimes rely on the definition of environment
2724 variables for their search paths (see explanation of
2725 @code{--search-paths} below). Any missing or possibly incorrect
2726 environment variable definitions are reported here.
2728 @item --install-from-expression=@var{exp}
2730 Install the package @var{exp} evaluates to.
2732 @var{exp} must be a Scheme expression that evaluates to a
2733 @code{<package>} object. This option is notably useful to disambiguate
2734 between same-named variants of a package, with expressions such as
2735 @code{(@@ (gnu packages base) guile-final)}.
2737 Note that this option installs the first output of the specified
2738 package, which may be insufficient when needing a specific output of a
2739 multiple-output package.
2741 @item --install-from-file=@var{file}
2742 @itemx -f @var{file}
2743 Install the package that the code within @var{file} evaluates to.
2745 As an example, @var{file} might contain a definition like this
2746 (@pxref{Defining Packages}):
2749 @verbatiminclude package-hello.scm
2752 Developers may find it useful to include such a @file{guix.scm} file
2753 in the root of their project source tree that can be used to test
2754 development snapshots and create reproducible development environments
2755 (@pxref{Invoking guix environment}).
2757 @item --remove=@var{package} @dots{}
2758 @itemx -r @var{package} @dots{}
2759 Remove the specified @var{package}s.
2761 As for @code{--install}, each @var{package} may specify a version number
2762 and/or output name in addition to the package name. For instance,
2763 @code{-r glibc:debug} would remove the @code{debug} output of
2766 @item --upgrade[=@var{regexp} @dots{}]
2767 @itemx -u [@var{regexp} @dots{}]
2768 @cindex upgrading packages
2769 Upgrade all the installed packages. If one or more @var{regexp}s are
2770 specified, upgrade only installed packages whose name matches a
2771 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2773 Note that this upgrades package to the latest version of packages found
2774 in the distribution currently installed. To update your distribution,
2775 you should regularly run @command{guix pull} (@pxref{Invoking guix
2778 @item --do-not-upgrade[=@var{regexp} @dots{}]
2779 When used together with the @code{--upgrade} option, do @emph{not}
2780 upgrade any packages whose name matches a @var{regexp}. For example, to
2781 upgrade all packages in the current profile except those containing the
2782 substring ``emacs'':
2785 $ guix package --upgrade . --do-not-upgrade emacs
2788 @item @anchor{profile-manifest}--manifest=@var{file}
2789 @itemx -m @var{file}
2790 @cindex profile declaration
2791 @cindex profile manifest
2792 Create a new generation of the profile from the manifest object
2793 returned by the Scheme code in @var{file}.
2795 This allows you to @emph{declare} the profile's contents rather than
2796 constructing it through a sequence of @code{--install} and similar
2797 commands. The advantage is that @var{file} can be put under version
2798 control, copied to different machines to reproduce the same profile, and
2801 @c FIXME: Add reference to (guix profile) documentation when available.
2802 @var{file} must return a @dfn{manifest} object, which is roughly a list
2805 @findex packages->manifest
2807 (use-package-modules guile emacs)
2812 ;; Use a specific package output.
2813 (list guile-2.0 "debug")))
2816 @findex specifications->manifest
2817 In this example we have to know which modules define the @code{emacs}
2818 and @code{guile-2.0} variables to provide the right
2819 @code{use-package-modules} line, which can be cumbersome. We can
2820 instead provide regular package specifications and let
2821 @code{specifications->manifest} look up the corresponding package
2825 (specifications->manifest
2826 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2830 @cindex rolling back
2831 @cindex undoing transactions
2832 @cindex transactions, undoing
2833 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2834 the last transaction.
2836 When combined with options such as @code{--install}, roll back occurs
2837 before any other actions.
2839 When rolling back from the first generation that actually contains
2840 installed packages, the profile is made to point to the @dfn{zeroth
2841 generation}, which contains no files apart from its own metadata.
2843 After having rolled back, installing, removing, or upgrading packages
2844 overwrites previous future generations. Thus, the history of the
2845 generations in a profile is always linear.
2847 @item --switch-generation=@var{pattern}
2848 @itemx -S @var{pattern}
2850 Switch to a particular generation defined by @var{pattern}.
2852 @var{pattern} may be either a generation number or a number prefixed
2853 with ``+'' or ``-''. The latter means: move forward/backward by a
2854 specified number of generations. For example, if you want to return to
2855 the latest generation after @code{--roll-back}, use
2856 @code{--switch-generation=+1}.
2858 The difference between @code{--roll-back} and
2859 @code{--switch-generation=-1} is that @code{--switch-generation} will
2860 not make a zeroth generation, so if a specified generation does not
2861 exist, the current generation will not be changed.
2863 @item --search-paths[=@var{kind}]
2864 @cindex search paths
2865 Report environment variable definitions, in Bash syntax, that may be
2866 needed in order to use the set of installed packages. These environment
2867 variables are used to specify @dfn{search paths} for files used by some
2868 of the installed packages.
2870 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2871 environment variables to be defined so it can look for headers and
2872 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2873 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2874 library are installed in the profile, then @code{--search-paths} will
2875 suggest setting these variables to @code{@var{profile}/include} and
2876 @code{@var{profile}/lib}, respectively.
2878 The typical use case is to define these environment variables in the
2882 $ eval `guix package --search-paths`
2885 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2886 meaning that the returned environment variable definitions will either
2887 be exact settings, or prefixes or suffixes of the current value of these
2888 variables. When omitted, @var{kind} defaults to @code{exact}.
2890 This option can also be used to compute the @emph{combined} search paths
2891 of several profiles. Consider this example:
2894 $ guix package -p foo -i guile
2895 $ guix package -p bar -i guile-json
2896 $ guix package -p foo -p bar --search-paths
2899 The last command above reports about the @code{GUILE_LOAD_PATH}
2900 variable, even though, taken individually, neither @file{foo} nor
2901 @file{bar} would lead to that recommendation.
2904 @item --profile=@var{profile}
2905 @itemx -p @var{profile}
2906 Use @var{profile} instead of the user's default profile.
2908 @cindex collisions, in a profile
2909 @cindex colliding packages in profiles
2910 @cindex profile collisions
2911 @item --allow-collisions
2912 Allow colliding packages in the new profile. Use at your own risk!
2914 By default, @command{guix package} reports as an error @dfn{collisions}
2915 in the profile. Collisions happen when two or more different versions
2916 or variants of a given package end up in the profile.
2919 Use the bootstrap Guile to build the profile. This option is only
2920 useful to distribution developers.
2924 In addition to these actions, @command{guix package} supports the
2925 following options to query the current state of a profile, or the
2926 availability of packages:
2930 @item --search=@var{regexp}
2931 @itemx -s @var{regexp}
2932 @cindex searching for packages
2933 List the available packages whose name, synopsis, or description matches
2934 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
2935 Print all the metadata of matching packages in
2936 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
2937 GNU recutils manual}).
2939 This allows specific fields to be extracted using the @command{recsel}
2940 command, for instance:
2943 $ guix package -s malloc | recsel -p name,version,relevance
2957 Similarly, to show the name of all the packages available under the
2958 terms of the GNU@tie{}LGPL version 3:
2961 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
2968 It is also possible to refine search results using several @code{-s} flags to
2969 @command{guix package}, or several arguments to @command{guix search}. For
2970 example, the following command returns a list of board games (this time using
2971 the @command{guix search} alias):
2974 $ guix search '\<board\>' game | recsel -p name
2979 If we were to omit @code{-s game}, we would also get software packages
2980 that deal with printed circuit boards; removing the angle brackets
2981 around @code{board} would further add packages that have to do with
2984 And now for a more elaborate example. The following command searches
2985 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
2986 libraries, and prints the name and synopsis of the matching packages:
2989 $ guix search crypto library | \
2990 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
2994 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
2995 information on @dfn{selection expressions} for @code{recsel -e}.
2997 @item --show=@var{package}
2998 Show details about @var{package}, taken from the list of available packages, in
2999 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3003 $ guix package --show=python | recsel -p name,version
3011 You may also specify the full name of a package to only get details about a
3012 specific version of it:
3014 $ guix package --show=python@@3.4 | recsel -p name,version
3021 @item --list-installed[=@var{regexp}]
3022 @itemx -I [@var{regexp}]
3023 List the currently installed packages in the specified profile, with the
3024 most recently installed packages shown last. When @var{regexp} is
3025 specified, list only installed packages whose name matches @var{regexp}.
3027 For each installed package, print the following items, separated by
3028 tabs: the package name, its version string, the part of the package that
3029 is installed (for instance, @code{out} for the default output,
3030 @code{include} for its headers, etc.), and the path of this package in
3033 @item --list-available[=@var{regexp}]
3034 @itemx -A [@var{regexp}]
3035 List packages currently available in the distribution for this system
3036 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3037 installed packages whose name matches @var{regexp}.
3039 For each package, print the following items separated by tabs: its name,
3040 its version string, the parts of the package (@pxref{Packages with
3041 Multiple Outputs}), and the source location of its definition.
3043 @item --list-generations[=@var{pattern}]
3044 @itemx -l [@var{pattern}]
3046 Return a list of generations along with their creation dates; for each
3047 generation, show the installed packages, with the most recently
3048 installed packages shown last. Note that the zeroth generation is never
3051 For each installed package, print the following items, separated by
3052 tabs: the name of a package, its version string, the part of the package
3053 that is installed (@pxref{Packages with Multiple Outputs}), and the
3054 location of this package in the store.
3056 When @var{pattern} is used, the command returns only matching
3057 generations. Valid patterns include:
3060 @item @emph{Integers and comma-separated integers}. Both patterns denote
3061 generation numbers. For instance, @code{--list-generations=1} returns
3064 And @code{--list-generations=1,8,2} outputs three generations in the
3065 specified order. Neither spaces nor trailing commas are allowed.
3067 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3068 specified generations and everything in between. Note that the start of
3069 a range must be smaller than its end.
3071 It is also possible to omit the endpoint. For example,
3072 @code{--list-generations=2..}, returns all generations starting from the
3075 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3076 or months by passing an integer along with the first letter of the
3077 duration. For example, @code{--list-generations=20d} lists generations
3078 that are up to 20 days old.
3081 @item --delete-generations[=@var{pattern}]
3082 @itemx -d [@var{pattern}]
3083 When @var{pattern} is omitted, delete all generations except the current
3086 This command accepts the same patterns as @option{--list-generations}.
3087 When @var{pattern} is specified, delete the matching generations. When
3088 @var{pattern} specifies a duration, generations @emph{older} than the
3089 specified duration match. For instance, @code{--delete-generations=1m}
3090 deletes generations that are more than one month old.
3092 If the current generation matches, it is @emph{not} deleted. Also, the
3093 zeroth generation is never deleted.
3095 Note that deleting generations prevents rolling back to them.
3096 Consequently, this command must be used with care.
3100 Finally, since @command{guix package} may actually start build
3101 processes, it supports all the common build options (@pxref{Common Build
3102 Options}). It also supports package transformation options, such as
3103 @option{--with-source} (@pxref{Package Transformation Options}).
3104 However, note that package transformations are lost when upgrading; to
3105 preserve transformations across upgrades, you should define your own
3106 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3107 (@pxref{Defining Packages}).
3110 @section Substitutes
3113 @cindex pre-built binaries
3114 Guix supports transparent source/binary deployment, which means that it
3115 can either build things locally, or download pre-built items from a
3116 server, or both. We call these pre-built items @dfn{substitutes}---they
3117 are substitutes for local build results. In many cases, downloading a
3118 substitute is much faster than building things locally.
3120 Substitutes can be anything resulting from a derivation build
3121 (@pxref{Derivations}). Of course, in the common case, they are
3122 pre-built package binaries, but source tarballs, for instance, which
3123 also result from derivation builds, can be available as substitutes.
3126 * Official Substitute Server:: One particular source of substitutes.
3127 * Substitute Server Authorization:: How to enable or disable substitutes.
3128 * Substitute Authentication:: How Guix verifies substitutes.
3129 * Proxy Settings:: How to get substitutes via proxy.
3130 * Substitution Failure:: What happens when substitution fails.
3131 * On Trusting Binaries:: How can you trust that binary blob?
3134 @node Official Substitute Server
3135 @subsection Official Substitute Server
3139 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3140 that builds packages from Guix continuously for some
3141 architectures, and makes them available as substitutes. This is the
3142 default source of substitutes; it can be overridden by passing the
3143 @option{--substitute-urls} option either to @command{guix-daemon}
3144 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3145 or to client tools such as @command{guix package}
3146 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3149 Substitute URLs can be either HTTP or HTTPS.
3150 HTTPS is recommended because communications are encrypted; conversely,
3151 using HTTP makes all communications visible to an eavesdropper, who
3152 could use the information gathered to determine, for instance, whether
3153 your system has unpatched security vulnerabilities.
3155 Substitutes from the official build farm are enabled by default when
3156 using Guix System (@pxref{GNU Distribution}). However,
3157 they are disabled by default when using Guix on a foreign distribution,
3158 unless you have explicitly enabled them via one of the recommended
3159 installation steps (@pxref{Installation}). The following paragraphs
3160 describe how to enable or disable substitutes for the official build
3161 farm; the same procedure can also be used to enable substitutes for any
3162 other substitute server.
3164 @node Substitute Server Authorization
3165 @subsection Substitute Server Authorization
3168 @cindex substitutes, authorization thereof
3169 @cindex access control list (ACL), for substitutes
3170 @cindex ACL (access control list), for substitutes
3171 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3173 must add its public key to the access control list (ACL) of archive
3174 imports, using the @command{guix archive} command (@pxref{Invoking guix
3175 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3176 be compromised and to serve genuine substitutes.
3178 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3179 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3180 the installation prefix of Guix. If you installed Guix from source,
3181 make sure you checked the GPG signature of
3182 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3183 Then, you can run something like this:
3186 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3190 Similarly, the @file{hydra.gnu.org.pub} file contains the public key
3191 of an independent build farm also run by the project, reachable at
3192 @indicateurl{https://mirror.hydra.gnu.org}.
3195 Once this is in place, the output of a command like @code{guix build}
3196 should change from something like:
3199 $ guix build emacs --dry-run
3200 The following derivations would be built:
3201 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3202 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3203 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3204 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3212 $ guix build emacs --dry-run
3213 112.3 MB would be downloaded:
3214 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3215 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3216 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3217 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3222 This indicates that substitutes from @code{@value{SUBSTITUTE-SERVER}} are usable and
3223 will be downloaded, when possible, for future builds.
3225 @cindex substitutes, how to disable
3226 The substitute mechanism can be disabled globally by running
3227 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3228 guix-daemon}). It can also be disabled temporarily by passing the
3229 @code{--no-substitutes} option to @command{guix package}, @command{guix
3230 build}, and other command-line tools.
3232 @node Substitute Authentication
3233 @subsection Substitute Authentication
3235 @cindex digital signatures
3236 Guix detects and raises an error when attempting to use a substitute
3237 that has been tampered with. Likewise, it ignores substitutes that are
3238 not signed, or that are not signed by one of the keys listed in the ACL.
3240 There is one exception though: if an unauthorized server provides
3241 substitutes that are @emph{bit-for-bit identical} to those provided by
3242 an authorized server, then the unauthorized server becomes eligible for
3243 downloads. For example, assume we have chosen two substitute servers
3247 --substitute-urls="https://a.example.org https://b.example.org"
3251 @cindex reproducible builds
3252 If the ACL contains only the key for @code{b.example.org}, and if
3253 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3254 then Guix will download substitutes from @code{a.example.org} because it
3255 comes first in the list and can be considered a mirror of
3256 @code{b.example.org}. In practice, independent build machines usually
3257 produce the same binaries, thanks to bit-reproducible builds (see
3260 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3261 (in other words, the server is not authenticated), contrary to what
3262 HTTPS clients such as Web browsers usually do. This is because Guix
3263 authenticates substitute information itself, as explained above, which
3264 is what we care about (whereas X.509 certificates are about
3265 authenticating bindings between domain names and public keys.)
3267 @node Proxy Settings
3268 @subsection Proxy Settings
3271 Substitutes are downloaded over HTTP or HTTPS.
3272 The @code{http_proxy} environment
3273 variable can be set in the environment of @command{guix-daemon} and is
3274 honored for downloads of substitutes. Note that the value of
3275 @code{http_proxy} in the environment where @command{guix build},
3276 @command{guix package}, and other client commands are run has
3277 @emph{absolutely no effect}.
3279 @node Substitution Failure
3280 @subsection Substitution Failure
3282 Even when a substitute for a derivation is available, sometimes the
3283 substitution attempt will fail. This can happen for a variety of
3284 reasons: the substitute server might be offline, the substitute may
3285 recently have been deleted, the connection might have been interrupted,
3288 When substitutes are enabled and a substitute for a derivation is
3289 available, but the substitution attempt fails, Guix will attempt to
3290 build the derivation locally depending on whether or not
3291 @code{--fallback} was given (@pxref{fallback-option,, common build
3292 option @code{--fallback}}). Specifically, if @code{--fallback} was
3293 omitted, then no local build will be performed, and the derivation is
3294 considered to have failed. However, if @code{--fallback} was given,
3295 then Guix will attempt to build the derivation locally, and the success
3296 or failure of the derivation depends on the success or failure of the
3297 local build. Note that when substitutes are disabled or no substitute
3298 is available for the derivation in question, a local build will
3299 @emph{always} be performed, regardless of whether or not
3300 @code{--fallback} was given.
3302 To get an idea of how many substitutes are available right now, you can
3303 try running the @command{guix weather} command (@pxref{Invoking guix
3304 weather}). This command provides statistics on the substitutes provided
3307 @node On Trusting Binaries
3308 @subsection On Trusting Binaries
3310 @cindex trust, of pre-built binaries
3311 Today, each individual's control over their own computing is at the
3312 mercy of institutions, corporations, and groups with enough power and
3313 determination to subvert the computing infrastructure and exploit its
3314 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3315 convenient, we encourage users to also build on their own, or even run
3316 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3317 interesting target. One way to help is by publishing the software you
3318 build using @command{guix publish} so that others have one more choice
3319 of server to download substitutes from (@pxref{Invoking guix publish}).
3321 Guix has the foundations to maximize build reproducibility
3322 (@pxref{Features}). In most cases, independent builds of a given
3323 package or derivation should yield bit-identical results. Thus, through
3324 a diverse set of independent package builds, we can strengthen the
3325 integrity of our systems. The @command{guix challenge} command aims to
3326 help users assess substitute servers, and to assist developers in
3327 finding out about non-deterministic package builds (@pxref{Invoking guix
3328 challenge}). Similarly, the @option{--check} option of @command{guix
3329 build} allows users to check whether previously-installed substitutes
3330 are genuine by rebuilding them locally (@pxref{build-check,
3331 @command{guix build --check}}).
3333 In the future, we want Guix to have support to publish and retrieve
3334 binaries to/from other users, in a peer-to-peer fashion. If you would
3335 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3337 @node Packages with Multiple Outputs
3338 @section Packages with Multiple Outputs
3340 @cindex multiple-output packages
3341 @cindex package outputs
3344 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3345 source package leads to exactly one directory in the store. When running
3346 @command{guix install glibc}, one installs the default output of the
3347 GNU libc package; the default output is called @code{out}, but its name
3348 can be omitted as shown in this command. In this particular case, the
3349 default output of @code{glibc} contains all the C header files, shared
3350 libraries, static libraries, Info documentation, and other supporting
3353 Sometimes it is more appropriate to separate the various types of files
3354 produced from a single source package into separate outputs. For
3355 instance, the GLib C library (used by GTK+ and related packages)
3356 installs more than 20 MiB of reference documentation as HTML pages.
3357 To save space for users who do not need it, the documentation goes to a
3358 separate output, called @code{doc}. To install the main GLib output,
3359 which contains everything but the documentation, one would run:
3365 @cindex documentation
3366 The command to install its documentation is:
3369 guix install glib:doc
3372 Some packages install programs with different ``dependency footprints''.
3373 For instance, the WordNet package installs both command-line tools and
3374 graphical user interfaces (GUIs). The former depend solely on the C
3375 library, whereas the latter depend on Tcl/Tk and the underlying X
3376 libraries. In this case, we leave the command-line tools in the default
3377 output, whereas the GUIs are in a separate output. This allows users
3378 who do not need the GUIs to save space. The @command{guix size} command
3379 can help find out about such situations (@pxref{Invoking guix size}).
3380 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3382 There are several such multiple-output packages in the GNU distribution.
3383 Other conventional output names include @code{lib} for libraries and
3384 possibly header files, @code{bin} for stand-alone programs, and
3385 @code{debug} for debugging information (@pxref{Installing Debugging
3386 Files}). The outputs of a packages are listed in the third column of
3387 the output of @command{guix package --list-available} (@pxref{Invoking
3391 @node Invoking guix gc
3392 @section Invoking @command{guix gc}
3394 @cindex garbage collector
3396 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3397 The @command{guix gc} command allows users to explicitly run the garbage
3398 collector to reclaim space from the @file{/gnu/store} directory. It is
3399 the @emph{only} way to remove files from @file{/gnu/store}---removing
3400 files or directories manually may break it beyond repair!
3403 @cindex garbage collector roots
3404 The garbage collector has a set of known @dfn{roots}: any file under
3405 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3406 cannot be deleted; any other file is considered @dfn{dead} and may be
3407 deleted. The set of garbage collector roots (``GC roots'' for short)
3408 includes default user profiles; by default, the symlinks under
3409 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3410 added with @command{guix build --root}, for example (@pxref{Invoking
3411 guix build}). The @command{guix gc --list-roots} command lists them.
3413 Prior to running @code{guix gc --collect-garbage} to make space, it is
3414 often useful to remove old generations from user profiles; that way, old
3415 package builds referenced by those generations can be reclaimed. This
3416 is achieved by running @code{guix package --delete-generations}
3417 (@pxref{Invoking guix package}).
3419 Our recommendation is to run a garbage collection periodically, or when
3420 you are short on disk space. For instance, to guarantee that at least
3421 5@tie{}GB are available on your disk, simply run:
3427 It is perfectly safe to run as a non-interactive periodic job
3428 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3429 Running @command{guix gc} with no arguments will collect as
3430 much garbage as it can, but that is often inconvenient: you may find
3431 yourself having to rebuild or re-download software that is ``dead'' from
3432 the GC viewpoint but that is necessary to build other pieces of
3433 software---e.g., the compiler tool chain.
3435 The @command{guix gc} command has three modes of operation: it can be
3436 used to garbage-collect any dead files (the default), to delete specific
3437 files (the @code{--delete} option), to print garbage-collector
3438 information, or for more advanced queries. The garbage collection
3439 options are as follows:
3442 @item --collect-garbage[=@var{min}]
3443 @itemx -C [@var{min}]
3444 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3445 sub-directories. This is the default operation when no option is
3448 When @var{min} is given, stop once @var{min} bytes have been collected.
3449 @var{min} may be a number of bytes, or it may include a unit as a
3450 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3451 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3453 When @var{min} is omitted, collect all the garbage.
3455 @item --free-space=@var{free}
3456 @itemx -F @var{free}
3457 Collect garbage until @var{free} space is available under
3458 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3459 as @code{500MiB}, as described above.
3461 When @var{free} or more is already available in @file{/gnu/store}, do
3462 nothing and exit immediately.
3464 @item --delete-generations[=@var{duration}]
3465 @itemx -d [@var{duration}]
3466 Before starting the garbage collection process, delete all the generations
3467 older than @var{duration}, for all the user profiles; when run as root, this
3468 applies to all the profiles @emph{of all the users}.
3470 For example, this command deletes all the generations of all your profiles
3471 that are older than 2 months (except generations that are current), and then
3472 proceeds to free space until at least 10 GiB are available:
3475 guix gc -d 2m -F 10G
3480 Attempt to delete all the store files and directories specified as
3481 arguments. This fails if some of the files are not in the store, or if
3482 they are still live.
3484 @item --list-failures
3485 List store items corresponding to cached build failures.
3487 This prints nothing unless the daemon was started with
3488 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3489 @option{--cache-failures}}).
3492 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3495 @item --clear-failures
3496 Remove the specified store items from the failed-build cache.
3498 Again, this option only makes sense when the daemon is started with
3499 @option{--cache-failures}. Otherwise, it does nothing.
3502 Show the list of dead files and directories still present in the
3503 store---i.e., files and directories no longer reachable from any root.
3506 Show the list of live store files and directories.
3510 In addition, the references among existing store files can be queried:
3516 @cindex package dependencies
3517 List the references (respectively, the referrers) of store files given
3523 List the requisites of the store files passed as arguments. Requisites
3524 include the store files themselves, their references, and the references
3525 of these, recursively. In other words, the returned list is the
3526 @dfn{transitive closure} of the store files.
3528 @xref{Invoking guix size}, for a tool to profile the size of the closure
3529 of an element. @xref{Invoking guix graph}, for a tool to visualize
3530 the graph of references.
3534 Return the derivation(s) leading to the given store items
3535 (@pxref{Derivations}).
3537 For example, this command:
3540 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3544 returns the @file{.drv} file(s) leading to the @code{emacs} package
3545 installed in your profile.
3547 Note that there may be zero matching @file{.drv} files, for instance
3548 because these files have been garbage-collected. There can also be more
3549 than one matching @file{.drv} due to fixed-output derivations.
3552 Lastly, the following options allow you to check the integrity of the
3553 store and to control disk usage.
3557 @item --verify[=@var{options}]
3558 @cindex integrity, of the store
3559 @cindex integrity checking
3560 Verify the integrity of the store.
3562 By default, make sure that all the store items marked as valid in the
3563 database of the daemon actually exist in @file{/gnu/store}.
3565 When provided, @var{options} must be a comma-separated list containing one
3566 or more of @code{contents} and @code{repair}.
3568 When passing @option{--verify=contents}, the daemon computes the
3569 content hash of each store item and compares it against its hash in the
3570 database. Hash mismatches are reported as data corruptions. Because it
3571 traverses @emph{all the files in the store}, this command can take a
3572 long time, especially on systems with a slow disk drive.
3574 @cindex repairing the store
3575 @cindex corruption, recovering from
3576 Using @option{--verify=repair} or @option{--verify=contents,repair}
3577 causes the daemon to try to repair corrupt store items by fetching
3578 substitutes for them (@pxref{Substitutes}). Because repairing is not
3579 atomic, and thus potentially dangerous, it is available only to the
3580 system administrator. A lightweight alternative, when you know exactly
3581 which items in the store are corrupt, is @command{guix build --repair}
3582 (@pxref{Invoking guix build}).
3585 @cindex deduplication
3586 Optimize the store by hard-linking identical files---this is
3587 @dfn{deduplication}.
3589 The daemon performs deduplication after each successful build or archive
3590 import, unless it was started with @code{--disable-deduplication}
3591 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3592 this option is primarily useful when the daemon was running with
3593 @code{--disable-deduplication}.
3597 @node Invoking guix pull
3598 @section Invoking @command{guix pull}
3600 @cindex upgrading Guix
3601 @cindex updating Guix
3602 @cindex @command{guix pull}
3604 Packages are installed or upgraded to the latest version available in
3605 the distribution currently available on your local machine. To update
3606 that distribution, along with the Guix tools, you must run @command{guix
3607 pull}: the command downloads the latest Guix source code and package
3608 descriptions, and deploys it. Source code is downloaded from a
3609 @uref{https://git-scm.com, Git} repository, by default the official
3610 GNU@tie{}Guix repository, though this can be customized.
3612 On completion, @command{guix package} will use packages and package
3613 versions from this just-retrieved copy of Guix. Not only that, but all
3614 the Guix commands and Scheme modules will also be taken from that latest
3615 version. New @command{guix} sub-commands added by the update also
3618 Any user can update their Guix copy using @command{guix pull}, and the
3619 effect is limited to the user who run @command{guix pull}. For
3620 instance, when user @code{root} runs @command{guix pull}, this has no
3621 effect on the version of Guix that user @code{alice} sees, and vice
3624 The result of running @command{guix pull} is a @dfn{profile} available
3625 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3626 make sure to add it to the beginning of your search path so that you use
3627 the latest version, and similarly for the Info manual
3628 (@pxref{Documentation}):
3631 export PATH="$HOME/.config/guix/current/bin:$PATH"
3632 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3635 The @code{--list-generations} or @code{-l} option lists past generations
3636 produced by @command{guix pull}, along with details about their provenance:
3640 Generation 1 Jun 10 2018 00:18:18
3642 repository URL: https://git.savannah.gnu.org/git/guix.git
3643 branch: origin/master
3644 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3646 Generation 2 Jun 11 2018 11:02:49
3648 repository URL: https://git.savannah.gnu.org/git/guix.git
3649 branch: origin/master
3650 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3651 2 new packages: keepalived, libnfnetlink
3652 6 packages upgraded: emacs-nix-mode@@2.0.4,
3653 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3654 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3656 Generation 3 Jun 13 2018 23:31:07 (current)
3658 repository URL: https://git.savannah.gnu.org/git/guix.git
3659 branch: origin/master
3660 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3661 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3662 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3665 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3666 describe the current status of Guix.
3668 This @code{~/.config/guix/current} profile works like any other profile
3669 created by @command{guix package} (@pxref{Invoking guix package}). That
3670 is, you can list generations, roll back to the previous
3671 generation---i.e., the previous Guix---and so on:
3674 $ guix package -p ~/.config/guix/current --roll-back
3675 switched from generation 3 to 2
3676 $ guix package -p ~/.config/guix/current --delete-generations=1
3677 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3680 The @command{guix pull} command is usually invoked with no arguments,
3681 but it supports the following options:
3684 @item --url=@var{url}
3685 @itemx --commit=@var{commit}
3686 @itemx --branch=@var{branch}
3687 Download code for the @code{guix} channel from the specified @var{url}, at the
3688 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3689 string), or @var{branch}.
3691 @cindex @file{channels.scm}, configuration file
3692 @cindex configuration file for channels
3693 These options are provided for convenience, but you can also specify your
3694 configuration in the @file{~/.config/guix/channels.scm} file or using the
3695 @option{--channels} option (see below).
3697 @item --channels=@var{file}
3698 @itemx -C @var{file}
3699 Read the list of channels from @var{file} instead of
3700 @file{~/.config/guix/channels.scm}. @var{file} must contain Scheme code that
3701 evaluates to a list of channel objects. @xref{Channels}, for more
3706 Display the list of packages added or upgraded since the previous generation.
3708 This is the same information as displayed upon @command{guix pull} completion,
3709 but without ellipses; it is also similar to the output of @command{guix pull
3710 -l} for the last generation (see below).
3712 @item --list-generations[=@var{pattern}]
3713 @itemx -l [@var{pattern}]
3714 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3715 is provided, the subset of generations that match @var{pattern}.
3716 The syntax of @var{pattern} is the same as with @code{guix package
3717 --list-generations} (@pxref{Invoking guix package}).
3719 @xref{Invoking guix describe}, for a way to display information about the
3720 current generation only.
3722 @item --profile=@var{profile}
3723 @itemx -p @var{profile}
3724 Use @var{profile} instead of @file{~/.config/guix/current}.
3728 Show which channel commit(s) would be used and what would be built or
3729 substituted but do not actually do it.
3731 @item --system=@var{system}
3732 @itemx -s @var{system}
3733 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3734 the system type of the build host.
3737 Produce verbose output, writing build logs to the standard error output.
3740 Use the bootstrap Guile to build the latest Guix. This option is only
3741 useful to Guix developers.
3744 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3745 repository and branch to pull from, as well as @emph{additional} repositories
3746 containing package modules that should be deployed. @xref{Channels}, for more
3749 In addition, @command{guix pull} supports all the common build options
3750 (@pxref{Common Build Options}).
3756 @cindex @file{channels.scm}, configuration file
3757 @cindex configuration file for channels
3758 @cindex @command{guix pull}, configuration file
3759 @cindex configuration of @command{guix pull}
3760 Guix and its package collection are updated by running @command{guix pull}
3761 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3762 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3763 customized by defining @dfn{channels} in the
3764 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3765 of a Git repository to be deployed, and @command{guix pull} can be instructed
3766 to pull from one or more channels. In other words, channels can be used to
3767 @emph{customize} and to @emph{extend} Guix, as we will see below.
3769 @subsection Using a Custom Guix Channel
3771 The channel called @code{guix} specifies where Guix itself---its command-line
3772 tools as well as its package collection---should be downloaded. For instance,
3773 suppose you want to update from your own copy of the Guix repository at
3774 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3775 write in @code{~/.config/guix/channels.scm} this specification:
3778 ;; Tell 'guix pull' to use my own repo.
3781 (url "https://example.org/my-guix.git")
3782 (branch "super-hacks")))
3786 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3787 branch of the repository at @code{example.org}.
3789 @subsection Specifying Additional Channels
3791 @cindex extending the package collection (channels)
3792 @cindex personal packages (channels)
3793 @cindex channels, for personal packages
3794 You can also specify @emph{additional channels} to pull from. Let's say you
3795 have a bunch of custom package variants or personal packages that you think
3796 would make little sense to contribute to the Guix project, but would like to
3797 have these packages transparently available to you at the command line. You
3798 would first write modules containing those package definitions (@pxref{Package
3799 Modules}), maintain them in a Git repository, and then you and anyone else can
3800 use it as an additional channel to get packages from. Neat, no?
3802 @c What follows stems from discussions at
3803 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3804 @c earlier discussions on guix-devel@gnu.org.
3806 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3807 publish your personal channel to the world, we would like to share a few words
3812 Before publishing a channel, please consider contributing your package
3813 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3814 to free software of all sorts, and packages in Guix proper are readily
3815 available to all Guix users and benefit from the project's quality assurance
3819 When you maintain package definitions outside Guix, we, Guix developers,
3820 consider that @emph{the compatibility burden is on you}. Remember that
3821 package modules and package definitions are just Scheme code that uses various
3822 programming interfaces (APIs). We want to remain free to change these APIs to
3823 keep improving Guix, possibly in ways that break your channel. We never
3824 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
3828 Corollary: if you're using an external channel and that channel breaks, please
3829 @emph{report the issue to the channel authors}, not to the Guix project.
3832 You've been warned! Having said this, we believe external channels are a
3833 practical way to exert your freedom to augment Guix' package collection and to
3834 share your improvements, which are basic tenets of
3835 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
3836 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
3839 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
3840 @command{guix pull} to pull from it @emph{in addition} to the default Guix
3843 @vindex %default-channels
3845 ;; Add my personal packages to those Guix provides.
3847 (name 'my-personal-packages)
3848 (url "https://example.org/personal-packages.git"))
3853 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
3854 add a channel the list of channels that the variable @code{%default-channels}
3855 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
3856 Manual}). With this file in place, @command{guix pull} builds not only Guix
3857 but also the package modules from your own repository. The result in
3858 @file{~/.config/guix/current} is the union of Guix with your own package
3862 $ guix pull --list-generations
3864 Generation 19 Aug 27 2018 16:20:48
3866 repository URL: https://git.savannah.gnu.org/git/guix.git
3868 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
3869 my-personal-packages dd3df5e
3870 repository URL: https://example.org/personal-packages.git
3872 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
3873 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
3874 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
3878 The output of @command{guix pull} above shows that Generation@tie{}19 includes
3879 both Guix and packages from the @code{my-personal-packages} channel. Among
3880 the new and upgraded packages that are listed, some like @code{my-gimp} and
3881 @code{my-emacs-with-cool-features} might come from
3882 @code{my-personal-packages}, while others come from the Guix default channel.
3884 To create a channel, create a Git repository containing your own package
3885 modules and make it available. The repository can contain anything, but a
3886 useful channel will contain Guile modules that export packages. Once you
3887 start using a channel, Guix will behave as if the root directory of that
3888 channel's Git repository has been added to the Guile load path (@pxref{Load
3889 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
3890 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
3891 module, then the module will be available under the name @code{(my-packages
3892 my-tools)}, and you will be able to use it like any other module
3893 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
3895 @cindex dependencies, channels
3896 @cindex meta-data, channels
3897 @subsection Declaring Channel Dependencies
3899 Channel authors may decide to augment a package collection provided by other
3900 channels. They can declare their channel to be dependent on other channels in
3901 a meta-data file @file{.guix-channel}, which is to be placed in the root of
3902 the channel repository.
3904 The meta-data file should contain a simple S-expression like this:
3911 (name some-collection)
3912 (url "https://example.org/first-collection.git"))
3914 (name some-other-collection)
3915 (url "https://example.org/second-collection.git")
3916 (branch "testing"))))
3919 In the above example this channel is declared to depend on two other channels,
3920 which will both be fetched automatically. The modules provided by the channel
3921 will be compiled in an environment where the modules of all these declared
3922 channels are available.
3924 For the sake of reliability and maintainability, you should avoid dependencies
3925 on channels that you don't control, and you should aim to keep the number of
3926 dependencies to a minimum.
3928 @subsection Replicating Guix
3930 @cindex pinning, channels
3931 @cindex replicating Guix
3932 @cindex reproducibility, of Guix
3933 The @command{guix pull --list-generations} output above shows precisely which
3934 commits were used to build this instance of Guix. We can thus replicate it,
3935 say, on another machine, by providing a channel specification in
3936 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
3939 ;; Deploy specific commits of my channels of interest.
3942 (url "https://git.savannah.gnu.org/git/guix.git")
3943 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
3945 (name 'my-personal-packages)
3946 (url "https://example.org/personal-packages.git")
3947 (branch "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
3950 The @command{guix describe --format=channels} command can even generate this
3951 list of channels directly (@pxref{Invoking guix describe}).
3953 At this point the two machines run the @emph{exact same Guix}, with access to
3954 the @emph{exact same packages}. The output of @command{guix build gimp} on
3955 one machine will be exactly the same, bit for bit, as the output of the same
3956 command on the other machine. It also means both machines have access to all
3957 the source code of Guix and, transitively, to all the source code of every
3960 This gives you super powers, allowing you to track the provenance of binary
3961 artifacts with very fine grain, and to reproduce software environments at
3962 will---some sort of ``meta reproducibility'' capabilities, if you will.
3963 @xref{Inferiors}, for another way to take advantage of these super powers.
3968 @c TODO: Remove this once we're more confident about API stability.
3970 The functionality described here is a ``technology preview'' as of version
3971 @value{VERSION}. As such, the interface is subject to change.
3975 @cindex composition of Guix revisions
3976 Sometimes you might need to mix packages from the revision of Guix you're
3977 currently running with packages available in a different revision of Guix.
3978 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
3979 revisions in arbitrary ways.
3981 @cindex inferior packages
3982 Technically, an ``inferior'' is essentially a separate Guix process connected
3983 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
3984 @code{(guix inferior)} module allows you to create inferiors and to
3985 communicate with them. It also provides a high-level interface to browse and
3986 manipulate the packages that an inferior provides---@dfn{inferior packages}.
3988 When combined with channels (@pxref{Channels}), inferiors provide a simple way
3989 to interact with a separate revision of Guix. For example, let's assume you
3990 want to install in your profile the current @code{guile} package, along with
3991 the @code{guile-json} as it existed in an older revision of Guix---perhaps
3992 because the newer @code{guile-json} has an incompatible API and you want to
3993 run your code against the old API@. To do that, you could write a manifest for
3994 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
3995 manifest, you would create an inferior for that old Guix revision you care
3996 about, and you would look up the @code{guile-json} package in the inferior:
3999 (use-modules (guix inferior) (guix channels)
4000 (srfi srfi-1)) ;for 'first'
4003 ;; This is the old revision from which we want to
4004 ;; extract guile-json.
4007 (url "https://git.savannah.gnu.org/git/guix.git")
4009 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4012 ;; An inferior representing the above revision.
4013 (inferior-for-channels channels))
4015 ;; Now create a manifest with the current "guile" package
4016 ;; and the old "guile-json" package.
4018 (list (first (lookup-inferior-packages inferior "guile-json"))
4019 (specification->package "guile")))
4022 On its first run, @command{guix package --manifest} might have to build the
4023 channel you specified before it can create the inferior; subsequent runs will
4024 be much faster because the Guix revision will be cached.
4026 The @code{(guix inferior)} module provides the following procedures to open an
4029 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4030 [#:cache-directory] [#:ttl]
4031 Return an inferior for @var{channels}, a list of channels. Use the cache at
4032 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4033 This procedure opens a new connection to the build daemon.
4035 As a side effect, this procedure may build or substitute binaries for
4036 @var{channels}, which can take time.
4039 @deffn {Scheme Procedure} open-inferior @var{directory} @
4040 [#:command "bin/guix"]
4041 Open the inferior Guix in @var{directory}, running
4042 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4043 the inferior could not be launched.
4046 @cindex inferior packages
4047 The procedures listed below allow you to obtain and manipulate inferior
4050 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4051 Return the list of packages known to @var{inferior}.
4054 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4056 Return the sorted list of inferior packages matching @var{name} in
4057 @var{inferior}, with highest version numbers first. If @var{version} is true,
4058 return only packages with a version number prefixed by @var{version}.
4061 @deffn {Scheme Procedure} inferior-package? @var{obj}
4062 Return true if @var{obj} is an inferior package.
4065 @deffn {Scheme Procedure} inferior-package-name @var{package}
4066 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4067 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4068 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4069 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4070 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4071 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4072 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4073 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4074 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4075 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4076 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4077 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4078 These procedures are the counterpart of package record accessors
4079 (@pxref{package Reference}). Most of them work by querying the inferior
4080 @var{package} comes from, so the inferior must still be live when you call
4084 Inferior packages can be used transparently like any other package or
4085 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4086 transparently handled by the @code{packages->manifest} procedure, which is
4087 commonly use in manifests (@pxref{Invoking guix package, the
4088 @option{--manifest} option of @command{guix package}}). Thus you can insert
4089 an inferior package pretty much anywhere you would insert a regular package:
4090 in manifests, in the @code{packages} field of your @code{operating-system}
4091 declaration, and so on.
4093 @node Invoking guix describe
4094 @section Invoking @command{guix describe}
4096 @cindex reproducibility
4097 @cindex replicating Guix
4098 Often you may want to answer questions like: ``Which revision of Guix am I
4099 using?'' or ``Which channels am I using?'' This is useful information in many
4100 situations: if you want to @emph{replicate} an environment on a different
4101 machine or user account, if you want to report a bug or to determine what
4102 change in the channels you are using caused it, or if you want to record your
4103 system state for reproducibility purposes. The @command{guix describe}
4104 command answers these questions.
4106 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4107 displays the channel(s) that it was built from, including their repository URL
4108 and commit IDs (@pxref{Channels}):
4112 Generation 10 Sep 03 2018 17:32:44 (current)
4114 repository URL: https://git.savannah.gnu.org/git/guix.git
4116 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4119 If you're familiar with the Git version control system, this is similar in
4120 spirit to @command{git describe}; the output is also similar to that of
4121 @command{guix pull --list-generations}, but limited to the current generation
4122 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4123 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4124 information is all it takes to describe the revision of Guix you're using, and
4125 also to replicate it.
4127 To make it easier to replicate Guix, @command{guix describe} can also be asked
4128 to return a list of channels instead of the human-readable description above:
4131 $ guix describe -f channels
4134 (url "https://git.savannah.gnu.org/git/guix.git")
4136 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4140 You can save this to a file and feed it to @command{guix pull -C} on some
4141 other machine or at a later point in time, which will instantiate @emph{this
4142 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4143 From there on, since you're able to deploy the same revision of Guix, you can
4144 just as well @emph{replicate a complete software environment}. We humbly
4145 think that this is @emph{awesome}, and we hope you'll like it too!
4147 The details of the options supported by @command{guix describe} are as
4151 @item --format=@var{format}
4152 @itemx -f @var{format}
4153 Produce output in the specified @var{format}, one of:
4157 produce human-readable output;
4159 produce a list of channel specifications that can be passed to @command{guix
4160 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4164 produce a list of channel specifications in JSON format;
4166 produce a list of channel specifications in Recutils format.
4169 @item --profile=@var{profile}
4170 @itemx -p @var{profile}
4171 Display information about @var{profile}.
4174 @node Invoking guix archive
4175 @section Invoking @command{guix archive}
4177 @cindex @command{guix archive}
4179 The @command{guix archive} command allows users to @dfn{export} files
4180 from the store into a single archive, and to later @dfn{import} them on
4181 a machine that runs Guix.
4182 In particular, it allows store files to be transferred from one machine
4183 to the store on another machine.
4186 If you're looking for a way to produce archives in a format suitable for
4187 tools other than Guix, @pxref{Invoking guix pack}.
4190 @cindex exporting store items
4191 To export store files as an archive to standard output, run:
4194 guix archive --export @var{options} @var{specifications}...
4197 @var{specifications} may be either store file names or package
4198 specifications, as for @command{guix package} (@pxref{Invoking guix
4199 package}). For instance, the following command creates an archive
4200 containing the @code{gui} output of the @code{git} package and the main
4201 output of @code{emacs}:
4204 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4207 If the specified packages are not built yet, @command{guix archive}
4208 automatically builds them. The build process may be controlled with the
4209 common build options (@pxref{Common Build Options}).
4211 To transfer the @code{emacs} package to a machine connected over SSH,
4215 guix archive --export -r emacs | ssh the-machine guix archive --import
4219 Similarly, a complete user profile may be transferred from one machine
4220 to another like this:
4223 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4224 ssh the-machine guix archive --import
4228 However, note that, in both examples, all of @code{emacs} and the
4229 profile as well as all of their dependencies are transferred (due to
4230 @code{-r}), regardless of what is already available in the store on the
4231 target machine. The @code{--missing} option can help figure out which
4232 items are missing from the target store. The @command{guix copy}
4233 command simplifies and optimizes this whole process, so this is probably
4234 what you should use in this case (@pxref{Invoking guix copy}).
4236 @cindex nar, archive format
4237 @cindex normalized archive (nar)
4238 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4239 comparable in spirit to `tar', but with differences
4240 that make it more appropriate for our purposes. First, rather than
4241 recording all Unix metadata for each file, the nar format only mentions
4242 the file type (regular, directory, or symbolic link); Unix permissions
4243 and owner/group are dismissed. Second, the order in which directory
4244 entries are stored always follows the order of file names according to
4245 the C locale collation order. This makes archive production fully
4248 When exporting, the daemon digitally signs the contents of the archive,
4249 and that digital signature is appended. When importing, the daemon
4250 verifies the signature and rejects the import in case of an invalid
4251 signature or if the signing key is not authorized.
4252 @c FIXME: Add xref to daemon doc about signatures.
4254 The main options are:
4258 Export the specified store files or packages (see below.) Write the
4259 resulting archive to the standard output.
4261 Dependencies are @emph{not} included in the output, unless
4262 @code{--recursive} is passed.
4266 When combined with @code{--export}, this instructs @command{guix
4267 archive} to include dependencies of the given items in the archive.
4268 Thus, the resulting archive is self-contained: it contains the closure
4269 of the exported store items.
4272 Read an archive from the standard input, and import the files listed
4273 therein into the store. Abort if the archive has an invalid digital
4274 signature, or if it is signed by a public key not among the authorized
4275 keys (see @code{--authorize} below.)
4278 Read a list of store file names from the standard input, one per line,
4279 and write on the standard output the subset of these files missing from
4282 @item --generate-key[=@var{parameters}]
4283 @cindex signing, archives
4284 Generate a new key pair for the daemon. This is a prerequisite before
4285 archives can be exported with @code{--export}. Note that this operation
4286 usually takes time, because it needs to gather enough entropy to
4287 generate the key pair.
4289 The generated key pair is typically stored under @file{/etc/guix}, in
4290 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4291 key, which must be kept secret.) When @var{parameters} is omitted,
4292 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4293 versions before 1.6.0, it is a 4096-bit RSA key.
4294 Alternatively, @var{parameters} can specify
4295 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4296 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4297 Libgcrypt Reference Manual}).
4300 @cindex authorizing, archives
4301 Authorize imports signed by the public key passed on standard input.
4302 The public key must be in ``s-expression advanced format''---i.e., the
4303 same format as the @file{signing-key.pub} file.
4305 The list of authorized keys is kept in the human-editable file
4306 @file{/etc/guix/acl}. The file contains
4307 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4308 s-expressions''} and is structured as an access-control list in the
4309 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4312 @item --extract=@var{directory}
4313 @itemx -x @var{directory}
4314 Read a single-item archive as served by substitute servers
4315 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4316 low-level operation needed in only very narrow use cases; see below.
4318 For example, the following command extracts the substitute for Emacs
4319 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4323 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-emacs-24.5 \
4324 | bunzip2 | guix archive -x /tmp/emacs
4327 Single-item archives are different from multiple-item archives produced
4328 by @command{guix archive --export}; they contain a single store item,
4329 and they do @emph{not} embed a signature. Thus this operation does
4330 @emph{no} signature verification and its output should be considered
4333 The primary purpose of this operation is to facilitate inspection of
4334 archive contents coming from possibly untrusted substitute servers.
4339 @c *********************************************************************
4341 @chapter Development
4343 @cindex software development
4344 If you are a software developer, Guix provides tools that you should find
4345 helpful---independently of the language you're developing in. This is what
4346 this chapter is about.
4348 The @command{guix environment} command provides a convenient way to set up
4349 @dfn{development environments} containing all the dependencies and tools
4350 necessary to work on the software package of your choice. The @command{guix
4351 pack} command allows you to create @dfn{application bundles} that can be
4352 easily distributed to users who do not run Guix.
4355 * Invoking guix environment:: Setting up development environments.
4356 * Invoking guix pack:: Creating software bundles.
4359 @node Invoking guix environment
4360 @section Invoking @command{guix environment}
4362 @cindex reproducible build environments
4363 @cindex development environments
4364 @cindex @command{guix environment}
4365 @cindex environment, package build environment
4366 The purpose of @command{guix environment} is to assist hackers in
4367 creating reproducible development environments without polluting their
4368 package profile. The @command{guix environment} tool takes one or more
4369 packages, builds all of their inputs, and creates a shell
4370 environment to use them.
4372 The general syntax is:
4375 guix environment @var{options} @var{package}@dots{}
4378 The following example spawns a new shell set up for the development of
4382 guix environment guile
4385 If the needed dependencies are not built yet, @command{guix environment}
4386 automatically builds them. The environment of the new shell is an augmented
4387 version of the environment that @command{guix environment} was run in.
4388 It contains the necessary search paths for building the given package
4389 added to the existing environment variables. To create a ``pure''
4390 environment, in which the original environment variables have been unset,
4391 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4392 environment variables such as @code{PATH} in their @file{~/.bashrc}
4393 file. As a consequence, when @code{guix environment} launches it, Bash
4394 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4395 environment variables. It is an error to define such environment
4396 variables in @file{.bashrc}; instead, they should be defined in
4397 @file{.bash_profile}, which is sourced only by log-in shells.
4398 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4399 details on Bash start-up files.}.
4401 @vindex GUIX_ENVIRONMENT
4402 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4403 variable in the shell it spawns; its value is the file name of the
4404 profile of this environment. This allows users to, say, define a
4405 specific prompt for development environments in their @file{.bashrc}
4406 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4409 if [ -n "$GUIX_ENVIRONMENT" ]
4411 export PS1="\u@@\h \w [dev]\$ "
4416 ...@: or to browse the profile:
4419 $ ls "$GUIX_ENVIRONMENT/bin"
4422 Additionally, more than one package may be specified, in which case the
4423 union of the inputs for the given packages are used. For example, the
4424 command below spawns a shell where all of the dependencies of both Guile
4425 and Emacs are available:
4428 guix environment guile emacs
4431 Sometimes an interactive shell session is not desired. An arbitrary
4432 command may be invoked by placing the @code{--} token to separate the
4433 command from the rest of the arguments:
4436 guix environment guile -- make -j4
4439 In other situations, it is more convenient to specify the list of
4440 packages needed in the environment. For example, the following command
4441 runs @command{python} from an environment containing Python@tie{}2.7 and
4445 guix environment --ad-hoc python2-numpy python-2.7 -- python
4448 Furthermore, one might want the dependencies of a package and also some
4449 additional packages that are not build-time or runtime dependencies, but
4450 are useful when developing nonetheless. Because of this, the
4451 @code{--ad-hoc} flag is positional. Packages appearing before
4452 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4453 added to the environment. Packages appearing after are interpreted as
4454 packages that will be added to the environment directly. For example,
4455 the following command creates a Guix development environment that
4456 additionally includes Git and strace:
4459 guix environment guix --ad-hoc git strace
4462 Sometimes it is desirable to isolate the environment as much as
4463 possible, for maximal purity and reproducibility. In particular, when
4464 using Guix on a host distro that is not Guix System, it is desirable to
4465 prevent access to @file{/usr/bin} and other system-wide resources from
4466 the development environment. For example, the following command spawns
4467 a Guile REPL in a ``container'' where only the store and the current
4468 working directory are mounted:
4471 guix environment --ad-hoc --container guile -- guile
4475 The @code{--container} option requires Linux-libre 3.19 or newer.
4478 The available options are summarized below.
4481 @item --root=@var{file}
4482 @itemx -r @var{file}
4483 @cindex persistent environment
4484 @cindex garbage collector root, for environments
4485 Make @var{file} a symlink to the profile for this environment, and
4486 register it as a garbage collector root.
4488 This is useful if you want to protect your environment from garbage
4489 collection, to make it ``persistent''.
4491 When this option is omitted, the environment is protected from garbage
4492 collection only for the duration of the @command{guix environment}
4493 session. This means that next time you recreate the same environment,
4494 you could have to rebuild or re-download packages. @xref{Invoking guix
4495 gc}, for more on GC roots.
4497 @item --expression=@var{expr}
4498 @itemx -e @var{expr}
4499 Create an environment for the package or list of packages that
4500 @var{expr} evaluates to.
4502 For example, running:
4505 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4508 starts a shell with the environment for this specific variant of the
4514 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4517 starts a shell with all the base system packages available.
4519 The above commands only use the default output of the given packages.
4520 To select other outputs, two element tuples can be specified:
4523 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4526 @item --load=@var{file}
4527 @itemx -l @var{file}
4528 Create an environment for the package or list of packages that the code
4529 within @var{file} evaluates to.
4531 As an example, @var{file} might contain a definition like this
4532 (@pxref{Defining Packages}):
4535 @verbatiminclude environment-gdb.scm
4538 @item --manifest=@var{file}
4539 @itemx -m @var{file}
4540 Create an environment for the packages contained in the manifest object
4541 returned by the Scheme code in @var{file}.
4543 This is similar to the same-named option in @command{guix package}
4544 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4548 Include all specified packages in the resulting environment, as if an
4549 @i{ad hoc} package were defined with them as inputs. This option is
4550 useful for quickly creating an environment without having to write a
4551 package expression to contain the desired inputs.
4553 For instance, the command:
4556 guix environment --ad-hoc guile guile-sdl -- guile
4559 runs @command{guile} in an environment where Guile and Guile-SDL are
4562 Note that this example implicitly asks for the default output of
4563 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4564 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4565 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4567 This option may be composed with the default behavior of @command{guix
4568 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4569 as packages whose dependencies will be added to the environment, the
4570 default behavior. Packages appearing after are interpreted as packages
4571 that will be added to the environment directly.
4574 Unset existing environment variables when building the new environment, except
4575 those specified with @option{--preserve} (see below.) This has the effect of
4576 creating an environment in which search paths only contain package inputs.
4578 @item --preserve=@var{regexp}
4579 @itemx -E @var{regexp}
4580 When used alongside @option{--pure}, preserve the environment variables
4581 matching @var{regexp}---in other words, put them on a ``white list'' of
4582 environment variables that must be preserved. This option can be repeated
4586 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4590 This example runs @command{mpirun} in a context where the only environment
4591 variables defined are @code{PATH}, environment variables whose name starts
4592 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4595 @item --search-paths
4596 Display the environment variable definitions that make up the
4599 @item --system=@var{system}
4600 @itemx -s @var{system}
4601 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4606 Run @var{command} within an isolated container. The current working
4607 directory outside the container is mapped inside the container.
4608 Additionally, unless overridden with @code{--user}, a dummy home
4609 directory is created that matches the current user's home directory, and
4610 @file{/etc/passwd} is configured accordingly.
4612 The spawned process runs as the current user outside the container. Inside
4613 the container, it has the same UID and GID as the current user, unless
4614 @option{--user} is passed (see below.)
4618 For containers, share the network namespace with the host system.
4619 Containers created without this flag only have access to the loopback
4622 @item --link-profile
4624 For containers, link the environment profile to
4625 @file{~/.guix-profile} within the container. This is equivalent to
4626 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4627 within the container. Linking will fail and abort the environment if
4628 the directory already exists, which will certainly be the case if
4629 @command{guix environment} was invoked in the user's home directory.
4631 Certain packages are configured to look in
4632 @code{~/.guix-profile} for configuration files and data;@footnote{For
4633 example, the @code{fontconfig} package inspects
4634 @file{~/.guix-profile/share/fonts} for additional fonts.}
4635 @code{--link-profile} allows these programs to behave as expected within
4638 @item --user=@var{user}
4639 @itemx -u @var{user}
4640 For containers, use the username @var{user} in place of the current
4641 user. The generated @file{/etc/passwd} entry within the container will
4642 contain the name @var{user}, the home directory will be
4643 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4644 the UID and GID inside the container are 1000. @var{user}
4645 need not exist on the system.
4647 Additionally, any shared or exposed path (see @code{--share} and
4648 @code{--expose} respectively) whose target is within the current user's
4649 home directory will be remapped relative to @file{/home/USER}; this
4650 includes the automatic mapping of the current working directory.
4653 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4655 guix environment --container --user=foo \
4656 --expose=$HOME/test \
4657 --expose=/tmp/target=$HOME/target
4660 While this will limit the leaking of user identity through home paths
4661 and each of the user fields, this is only one useful component of a
4662 broader privacy/anonymity solution---not one in and of itself.
4664 @item --expose=@var{source}[=@var{target}]
4665 For containers, expose the file system @var{source} from the host system
4666 as the read-only file system @var{target} within the container. If
4667 @var{target} is not specified, @var{source} is used as the target mount
4668 point in the container.
4670 The example below spawns a Guile REPL in a container in which the user's
4671 home directory is accessible read-only via the @file{/exchange}
4675 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
4678 @item --share=@var{source}[=@var{target}]
4679 For containers, share the file system @var{source} from the host system
4680 as the writable file system @var{target} within the container. If
4681 @var{target} is not specified, @var{source} is used as the target mount
4682 point in the container.
4684 The example below spawns a Guile REPL in a container in which the user's
4685 home directory is accessible for both reading and writing via the
4686 @file{/exchange} directory:
4689 guix environment --container --share=$HOME=/exchange --ad-hoc guile -- guile
4693 @command{guix environment}
4694 also supports all of the common build options that @command{guix
4695 build} supports (@pxref{Common Build Options}) as well as package
4696 transformation options (@pxref{Package Transformation Options}).
4698 @node Invoking guix pack
4699 @section Invoking @command{guix pack}
4701 Occasionally you want to pass software to people who are not (yet!)
4702 lucky enough to be using Guix. You'd tell them to run @command{guix
4703 package -i @var{something}}, but that's not possible in this case. This
4704 is where @command{guix pack} comes in.
4707 If you are looking for ways to exchange binaries among machines that
4708 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
4709 publish}, and @ref{Invoking guix archive}.
4714 @cindex application bundle
4715 @cindex software bundle
4716 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
4717 @dfn{software bundle}: it creates a tarball or some other archive
4718 containing the binaries of the software you're interested in, and all
4719 its dependencies. The resulting archive can be used on any machine that
4720 does not have Guix, and people can run the exact same binaries as those
4721 you have with Guix. The pack itself is created in a bit-reproducible
4722 fashion, so anyone can verify that it really contains the build results
4723 that you pretend to be shipping.
4725 For example, to create a bundle containing Guile, Emacs, Geiser, and all
4726 their dependencies, you can run:
4729 $ guix pack guile emacs geiser
4731 /gnu/store/@dots{}-pack.tar.gz
4734 The result here is a tarball containing a @file{/gnu/store} directory
4735 with all the relevant packages. The resulting tarball contains a
4736 @dfn{profile} with the three packages of interest; the profile is the
4737 same as would be created by @command{guix package -i}. It is this
4738 mechanism that is used to create Guix's own standalone binary tarball
4739 (@pxref{Binary Installation}).
4741 Users of this pack would have to run
4742 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
4743 find inconvenient. To work around it, you can create, say, a
4744 @file{/opt/gnu/bin} symlink to the profile:
4747 guix pack -S /opt/gnu/bin=bin guile emacs geiser
4751 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
4753 @cindex relocatable binaries, with @command{guix pack}
4754 What if the recipient of your pack does not have root privileges on
4755 their machine, and thus cannot unpack it in the root file system? In
4756 that case, you will want to use the @code{--relocatable} option (see
4757 below). This option produces @dfn{relocatable binaries}, meaning they
4758 they can be placed anywhere in the file system hierarchy: in the example
4759 above, users can unpack your tarball in their home directory and
4760 directly run @file{./opt/gnu/bin/guile}.
4762 @cindex Docker, build an image with guix pack
4763 Alternatively, you can produce a pack in the Docker image format using
4764 the following command:
4767 guix pack -f docker guile emacs geiser
4771 The result is a tarball that can be passed to the @command{docker load}
4773 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
4774 documentation} for more information.
4776 @cindex Singularity, build an image with guix pack
4777 @cindex SquashFS, build an image with guix pack
4778 Yet another option is to produce a SquashFS image with the following
4782 guix pack -f squashfs guile emacs geiser
4786 The result is a SquashFS file system image that can either be mounted or
4787 directly be used as a file system container image with the
4788 @uref{https://singularity.lbl.gov, Singularity container execution
4789 environment}, using commands like @command{singularity shell} or
4790 @command{singularity exec}.
4792 Several command-line options allow you to customize your pack:
4795 @item --format=@var{format}
4796 @itemx -f @var{format}
4797 Produce a pack in the given @var{format}.
4799 The available formats are:
4803 This is the default format. It produces a tarball containing all the
4804 specified binaries and symlinks.
4807 This produces a tarball that follows the
4808 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
4809 Docker Image Specification}.
4812 This produces a SquashFS image containing all the specified binaries and
4813 symlinks, as well as empty mount points for virtual file systems like
4817 @cindex relocatable binaries
4820 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
4821 anywhere in the file system hierarchy and run from there.
4823 When this option is passed once, the resulting binaries require support for
4824 @dfn{user namespaces} in the kernel Linux; when passed
4825 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
4826 PRoot support, can be thought of as the abbreviation of ``Really
4827 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
4828 if user namespaces are unavailable, and essentially work anywhere---see below
4829 for the implications.
4831 For example, if you create a pack containing Bash with:
4834 guix pack -RR -S /mybin=bin bash
4838 ...@: you can copy that pack to a machine that lacks Guix, and from your
4839 home directory as a normal user, run:
4847 In that shell, if you type @code{ls /gnu/store}, you'll notice that
4848 @file{/gnu/store} shows up and contains all the dependencies of
4849 @code{bash}, even though the machine actually lacks @file{/gnu/store}
4850 altogether! That is probably the simplest way to deploy Guix-built
4851 software on a non-Guix machine.
4854 By default, relocatable binaries rely on the @dfn{user namespace} feature of
4855 the kernel Linux, which allows unprivileged users to mount or change root.
4856 Old versions of Linux did not support it, and some GNU/Linux distributions
4859 To produce relocatable binaries that work even in the absence of user
4860 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
4861 case, binaries will try user namespace support and fall back to PRoot if user
4862 namespaces are not supported.
4864 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
4865 support for file system virtualization. It achieves that by using the
4866 @code{ptrace} system call on the running program. This approach has the
4867 advantage to work without requiring special kernel support, but it incurs
4868 run-time overhead every time a system call is made.
4871 @cindex entry point, for Docker images
4872 @item --entry-point=@var{command}
4873 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
4874 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
4875 support it. @var{command} must be relative to the profile contained in the
4878 The entry point specifies the command that tools like @code{docker run} or
4879 @code{singularity run} automatically start by default. For example, you can
4883 guix pack -f docker --entry-point=bin/guile guile
4886 The resulting pack can easily be loaded and @code{docker run} with no extra
4887 arguments will spawn @code{bin/guile}:
4890 docker load -i pack.tar.gz
4891 docker run @var{image-id}
4894 @item --expression=@var{expr}
4895 @itemx -e @var{expr}
4896 Consider the package @var{expr} evaluates to.
4898 This has the same purpose as the same-named option in @command{guix
4899 build} (@pxref{Additional Build Options, @code{--expression} in
4900 @command{guix build}}).
4902 @item --manifest=@var{file}
4903 @itemx -m @var{file}
4904 Use the packages contained in the manifest object returned by the Scheme
4907 This has a similar purpose as the same-named option in @command{guix
4908 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
4909 same manifest files. It allows you to define a collection of packages
4910 once and use it both for creating profiles and for creating archives
4911 for use on machines that do not have Guix installed. Note that you can
4912 specify @emph{either} a manifest file @emph{or} a list of packages,
4915 @item --system=@var{system}
4916 @itemx -s @var{system}
4917 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4918 the system type of the build host.
4920 @item --target=@var{triplet}
4921 @cindex cross-compilation
4922 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
4923 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
4924 configuration triplets,, autoconf, Autoconf}).
4926 @item --compression=@var{tool}
4927 @itemx -C @var{tool}
4928 Compress the resulting tarball using @var{tool}---one of @code{gzip},
4929 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
4931 @item --symlink=@var{spec}
4932 @itemx -S @var{spec}
4933 Add the symlinks specified by @var{spec} to the pack. This option can
4934 appear several times.
4936 @var{spec} has the form @code{@var{source}=@var{target}}, where
4937 @var{source} is the symlink that will be created and @var{target} is the
4940 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
4941 symlink pointing to the @file{bin} sub-directory of the profile.
4943 @item --save-provenance
4944 Save provenance information for the packages passed on the command line.
4945 Provenance information includes the URL and commit of the channels in use
4948 Provenance information is saved in the
4949 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
4950 usual package metadata---the name and version of each package, their
4951 propagated inputs, and so on. It is useful information to the recipient of
4952 the pack, who then knows how the pack was (supposedly) obtained.
4954 This option is not enabled by default because, like timestamps, provenance
4955 information contributes nothing to the build process. In other words, there
4956 is an infinity of channel URLs and commit IDs that can lead to the same pack.
4957 Recording such ``silent'' metadata in the output thus potentially breaks the
4958 source-to-binary bitwise reproducibility property.
4960 @item --root=@var{file}
4961 @itemx -r @var{file}
4962 @cindex garbage collector root, for packs
4963 Make @var{file} a symlink to the resulting pack, and register it as a garbage
4966 @item --localstatedir
4967 @itemx --profile-name=@var{name}
4968 Include the ``local state directory'', @file{/var/guix}, in the resulting
4969 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
4970 profile---by default @var{name} is @code{guix-profile}, which corresponds to
4971 @file{~root/.guix-profile}.
4973 @file{/var/guix} contains the store database (@pxref{The Store}) as well
4974 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
4975 the pack means that the store is ``complete'' and manageable by Guix;
4976 not providing it pack means that the store is ``dead'': items cannot be
4977 added to it or removed from it after extraction of the pack.
4979 One use case for this is the Guix self-contained binary tarball
4980 (@pxref{Binary Installation}).
4983 Use the bootstrap binaries to build the pack. This option is only
4984 useful to Guix developers.
4987 In addition, @command{guix pack} supports all the common build options
4988 (@pxref{Common Build Options}) and all the package transformation
4989 options (@pxref{Package Transformation Options}).
4992 @c *********************************************************************
4993 @node Programming Interface
4994 @chapter Programming Interface
4996 GNU Guix provides several Scheme programming interfaces (APIs) to
4997 define, build, and query packages. The first interface allows users to
4998 write high-level package definitions. These definitions refer to
4999 familiar packaging concepts, such as the name and version of a package,
5000 its build system, and its dependencies. These definitions can then be
5001 turned into concrete build actions.
5003 Build actions are performed by the Guix daemon, on behalf of users. In a
5004 standard setup, the daemon has write access to the store---the
5005 @file{/gnu/store} directory---whereas users do not. The recommended
5006 setup also has the daemon perform builds in chroots, under a specific
5007 build users, to minimize interference with the rest of the system.
5010 Lower-level APIs are available to interact with the daemon and the
5011 store. To instruct the daemon to perform a build action, users actually
5012 provide it with a @dfn{derivation}. A derivation is a low-level
5013 representation of the build actions to be taken, and the environment in
5014 which they should occur---derivations are to package definitions what
5015 assembly is to C programs. The term ``derivation'' comes from the fact
5016 that build results @emph{derive} from them.
5018 This chapter describes all these APIs in turn, starting from high-level
5019 package definitions.
5022 * Package Modules:: Packages from the programmer's viewpoint.
5023 * Defining Packages:: Defining new packages.
5024 * Build Systems:: Specifying how packages are built.
5025 * The Store:: Manipulating the package store.
5026 * Derivations:: Low-level interface to package derivations.
5027 * The Store Monad:: Purely functional interface to the store.
5028 * G-Expressions:: Manipulating build expressions.
5029 * Invoking guix repl:: Fiddling with Guix interactively.
5032 @node Package Modules
5033 @section Package Modules
5035 From a programming viewpoint, the package definitions of the
5036 GNU distribution are provided by Guile modules in the @code{(gnu packages
5037 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5038 packages @dots{})} module name space are not necessarily ``GNU
5039 packages''. This module naming scheme follows the usual Guile module
5040 naming convention: @code{gnu} means that these modules are distributed
5041 as part of the GNU system, and @code{packages} identifies modules that
5042 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5043 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5044 module exports a variable named @code{emacs}, which is bound to a
5045 @code{<package>} object (@pxref{Defining Packages}).
5047 The @code{(gnu packages @dots{})} module name space is
5048 automatically scanned for packages by the command-line tools. For
5049 instance, when running @code{guix install emacs}, all the @code{(gnu
5050 packages @dots{})} modules are scanned until one that exports a package
5051 object whose name is @code{emacs} is found. This package search
5052 facility is implemented in the @code{(gnu packages)} module.
5054 @cindex customization, of packages
5055 @cindex package module search path
5056 Users can store package definitions in modules with different
5057 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5058 name and module name must match. For instance, the @code{(my-packages
5059 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5060 relative to the load path specified with @option{--load-path} or
5061 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5062 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5063 these package definitions visible to the user interfaces:
5067 By adding the directory containing your package modules to the search path
5068 with the @code{-L} flag of @command{guix package} and other commands
5069 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5070 environment variable described below.
5073 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5074 pulls from it. A channel is essentially a Git repository containing package
5075 modules. @xref{Channels}, for more information on how to define and use
5079 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5081 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5082 This is a colon-separated list of directories to search for additional
5083 package modules. Directories listed in this variable take precedence
5084 over the own modules of the distribution.
5087 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5088 each package is built based solely on other packages in the
5089 distribution. The root of this dependency graph is a small set of
5090 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5091 bootstrap)} module. For more information on bootstrapping,
5092 @pxref{Bootstrapping}.
5094 @node Defining Packages
5095 @section Defining Packages
5097 The high-level interface to package definitions is implemented in the
5098 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5099 example, the package definition, or @dfn{recipe}, for the GNU Hello
5100 package looks like this:
5103 (define-module (gnu packages hello)
5104 #:use-module (guix packages)
5105 #:use-module (guix download)
5106 #:use-module (guix build-system gnu)
5107 #:use-module (guix licenses)
5108 #:use-module (gnu packages gawk))
5110 (define-public hello
5116 (uri (string-append "mirror://gnu/hello/hello-" version
5120 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5121 (build-system gnu-build-system)
5122 (arguments '(#:configure-flags '("--enable-silent-rules")))
5123 (inputs `(("gawk" ,gawk)))
5124 (synopsis "Hello, GNU world: An example GNU package")
5125 (description "Guess what GNU Hello prints!")
5126 (home-page "https://www.gnu.org/software/hello/")
5131 Without being a Scheme expert, the reader may have guessed the meaning
5132 of the various fields here. This expression binds the variable
5133 @code{hello} to a @code{<package>} object, which is essentially a record
5134 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5135 This package object can be inspected using procedures found in the
5136 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5137 returns---surprise!---@code{"hello"}.
5139 With luck, you may be able to import part or all of the definition of
5140 the package you are interested in from another repository, using the
5141 @code{guix import} command (@pxref{Invoking guix import}).
5143 In the example above, @var{hello} is defined in a module of its own,
5144 @code{(gnu packages hello)}. Technically, this is not strictly
5145 necessary, but it is convenient to do so: all the packages defined in
5146 modules under @code{(gnu packages @dots{})} are automatically known to
5147 the command-line tools (@pxref{Package Modules}).
5149 There are a few points worth noting in the above package definition:
5153 The @code{source} field of the package is an @code{<origin>} object
5154 (@pxref{origin Reference}, for the complete reference).
5155 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5156 meaning that the source is a file to be downloaded over FTP or HTTP.
5158 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5159 the GNU mirrors defined in @code{(guix download)}.
5161 The @code{sha256} field specifies the expected SHA256 hash of the file
5162 being downloaded. It is mandatory, and allows Guix to check the
5163 integrity of the file. The @code{(base32 @dots{})} form introduces the
5164 base32 representation of the hash. You can obtain this information with
5165 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5166 hash} (@pxref{Invoking guix hash}).
5169 When needed, the @code{origin} form can also have a @code{patches} field
5170 listing patches to be applied, and a @code{snippet} field giving a
5171 Scheme expression to modify the source code.
5174 @cindex GNU Build System
5175 The @code{build-system} field specifies the procedure to build the
5176 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5177 represents the familiar GNU Build System, where packages may be
5178 configured, built, and installed with the usual @code{./configure &&
5179 make && make check && make install} command sequence.
5182 The @code{arguments} field specifies options for the build system
5183 (@pxref{Build Systems}). Here it is interpreted by
5184 @var{gnu-build-system} as a request run @file{configure} with the
5185 @code{--enable-silent-rules} flag.
5191 What about these quote (@code{'}) characters? They are Scheme syntax to
5192 introduce a literal list; @code{'} is synonymous with @code{quote}.
5193 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5194 for details. Here the value of the @code{arguments} field is a list of
5195 arguments passed to the build system down the road, as with @code{apply}
5196 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5199 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5200 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5201 @code{#:configure-flags} is a keyword used to pass a keyword argument
5202 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5206 The @code{inputs} field specifies inputs to the build process---i.e.,
5207 build-time or run-time dependencies of the package. Here, we define an
5208 input called @code{"gawk"} whose value is that of the @var{gawk}
5209 variable; @var{gawk} is itself bound to a @code{<package>} object.
5211 @cindex backquote (quasiquote)
5214 @cindex comma (unquote)
5218 @findex unquote-splicing
5219 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5220 us to introduce a literal list in the @code{inputs} field, while
5221 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5222 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5225 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5226 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5227 of ensuring that they are present (@pxref{Build Systems}).
5229 However, any other dependencies need to be specified in the
5230 @code{inputs} field. Any dependency not specified here will simply be
5231 unavailable to the build process, possibly leading to a build failure.
5234 @xref{package Reference}, for a full description of possible fields.
5236 Once a package definition is in place, the
5237 package may actually be built using the @code{guix build} command-line
5238 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5239 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5240 package definition using the @command{guix edit} command
5241 (@pxref{Invoking guix edit}).
5242 @xref{Packaging Guidelines}, for
5243 more information on how to test package definitions, and
5244 @ref{Invoking guix lint}, for information on how to check a definition
5245 for style conformance.
5246 @vindex GUIX_PACKAGE_PATH
5247 Lastly, @pxref{Channels}, for information
5248 on how to extend the distribution by adding your own package definitions
5251 Finally, updating the package definition to a new upstream version
5252 can be partly automated by the @command{guix refresh} command
5253 (@pxref{Invoking guix refresh}).
5255 Behind the scenes, a derivation corresponding to the @code{<package>}
5256 object is first computed by the @code{package-derivation} procedure.
5257 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5258 The build actions it prescribes may then be realized by using the
5259 @code{build-derivations} procedure (@pxref{The Store}).
5261 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5262 Return the @code{<derivation>} object of @var{package} for @var{system}
5263 (@pxref{Derivations}).
5265 @var{package} must be a valid @code{<package>} object, and @var{system}
5266 must be a string denoting the target system type---e.g.,
5267 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5268 must be a connection to the daemon, which operates on the store
5269 (@pxref{The Store}).
5273 @cindex cross-compilation
5274 Similarly, it is possible to compute a derivation that cross-builds a
5275 package for some other system:
5277 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5278 @var{package} @var{target} [@var{system}]
5279 Return the @code{<derivation>} object of @var{package} cross-built from
5280 @var{system} to @var{target}.
5282 @var{target} must be a valid GNU triplet denoting the target hardware
5283 and operating system, such as @code{"mips64el-linux-gnu"}
5284 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5287 @cindex package transformations
5288 @cindex input rewriting
5289 @cindex dependency tree rewriting
5290 Packages can be manipulated in arbitrary ways. An example of a useful
5291 transformation is @dfn{input rewriting}, whereby the dependency tree of
5292 a package is rewritten by replacing specific inputs by others:
5294 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5295 [@var{rewrite-name}]
5296 Return a procedure that, when passed a package, replaces its direct and
5297 indirect dependencies (but not its implicit inputs) according to
5298 @var{replacements}. @var{replacements} is a list of package pairs; the
5299 first element of each pair is the package to replace, and the second one
5302 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5303 the name of a package and returns its new name after rewrite.
5307 Consider this example:
5310 (define libressl-instead-of-openssl
5311 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5313 (package-input-rewriting `((,openssl . ,libressl))))
5315 (define git-with-libressl
5316 (libressl-instead-of-openssl git))
5320 Here we first define a rewriting procedure that replaces @var{openssl}
5321 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5322 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5323 This is exactly what the @option{--with-input} command-line option does
5324 (@pxref{Package Transformation Options, @option{--with-input}}).
5326 The following variant of @code{package-input-rewriting} can match packages to
5327 be replaced by name rather than by identity.
5329 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5330 Return a procedure that, given a package, applies the given @var{replacements} to
5331 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5332 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5333 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5334 replacement for that package.
5337 The example above could be rewritten this way:
5340 (define libressl-instead-of-openssl
5341 ;; Replace all the packages called "openssl" with LibreSSL.
5342 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5345 The key difference here is that, this time, packages are matched by spec and
5346 not by identity. In other words, any package in the graph that is called
5347 @code{openssl} will be replaced.
5349 A more generic procedure to rewrite a package dependency graph is
5350 @code{package-mapping}: it supports arbitrary changes to nodes in the
5353 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5354 Return a procedure that, given a package, applies @var{proc} to all the packages
5355 depended on and returns the resulting package. The procedure stops recursion
5356 when @var{cut?} returns true for a given package.
5360 * package Reference:: The package data type.
5361 * origin Reference:: The origin data type.
5365 @node package Reference
5366 @subsection @code{package} Reference
5368 This section summarizes all the options available in @code{package}
5369 declarations (@pxref{Defining Packages}).
5371 @deftp {Data Type} package
5372 This is the data type representing a package recipe.
5376 The name of the package, as a string.
5378 @item @code{version}
5379 The version of the package, as a string.
5382 An object telling how the source code for the package should be
5383 acquired. Most of the time, this is an @code{origin} object, which
5384 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5385 can also be any other ``file-like'' object such as a @code{local-file},
5386 which denotes a file from the local file system (@pxref{G-Expressions,
5387 @code{local-file}}).
5389 @item @code{build-system}
5390 The build system that should be used to build the package (@pxref{Build
5393 @item @code{arguments} (default: @code{'()})
5394 The arguments that should be passed to the build system. This is a
5395 list, typically containing sequential keyword-value pairs.
5397 @item @code{inputs} (default: @code{'()})
5398 @itemx @code{native-inputs} (default: @code{'()})
5399 @itemx @code{propagated-inputs} (default: @code{'()})
5400 @cindex inputs, of packages
5401 These fields list dependencies of the package. Each one is a list of
5402 tuples, where each tuple has a label for the input (a string) as its
5403 first element, a package, origin, or derivation as its second element,
5404 and optionally the name of the output thereof that should be used, which
5405 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5406 more on package outputs). For example, the list below specifies three
5410 `(("libffi" ,libffi)
5411 ("libunistring" ,libunistring)
5412 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5415 @cindex cross compilation, package dependencies
5416 The distinction between @code{native-inputs} and @code{inputs} is
5417 necessary when considering cross-compilation. When cross-compiling,
5418 dependencies listed in @code{inputs} are built for the @emph{target}
5419 architecture; conversely, dependencies listed in @code{native-inputs}
5420 are built for the architecture of the @emph{build} machine.
5422 @code{native-inputs} is typically used to list tools needed at
5423 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5424 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5425 this area (@pxref{Invoking guix lint}).
5427 @anchor{package-propagated-inputs}
5428 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5429 specified packages will be automatically installed alongside the package
5430 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5431 package}}, for information on how @command{guix package} deals with
5434 For example this is necessary when a C/C++ library needs headers of
5435 another library to compile, or when a pkg-config file refers to another
5436 one @i{via} its @code{Requires} field.
5438 Another example where @code{propagated-inputs} is useful is for languages
5439 that lack a facility to record the run-time search path akin to the
5440 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5441 more. To ensure that libraries written in those languages can find
5442 library code they depend on at run time, run-time dependencies must be
5443 listed in @code{propagated-inputs} rather than @code{inputs}.
5445 @item @code{outputs} (default: @code{'("out")})
5446 The list of output names of the package. @xref{Packages with Multiple
5447 Outputs}, for typical uses of additional outputs.
5449 @item @code{native-search-paths} (default: @code{'()})
5450 @itemx @code{search-paths} (default: @code{'()})
5451 A list of @code{search-path-specification} objects describing
5452 search-path environment variables honored by the package.
5454 @item @code{replacement} (default: @code{#f})
5455 This must be either @code{#f} or a package object that will be used as a
5456 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5459 @item @code{synopsis}
5460 A one-line description of the package.
5462 @item @code{description}
5463 A more elaborate description of the package.
5465 @item @code{license}
5466 @cindex license, of packages
5467 The license of the package; a value from @code{(guix licenses)},
5468 or a list of such values.
5470 @item @code{home-page}
5471 The URL to the home-page of the package, as a string.
5473 @item @code{supported-systems} (default: @var{%supported-systems})
5474 The list of systems supported by the package, as strings of the form
5475 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5477 @item @code{maintainers} (default: @code{'()})
5478 The list of maintainers of the package, as @code{maintainer} objects.
5480 @item @code{location} (default: source location of the @code{package} form)
5481 The source location of the package. It is useful to override this when
5482 inheriting from another package, in which case this field is not
5483 automatically corrected.
5487 @deffn {Scheme Syntax} this-package
5488 When used in the @emph{lexical scope} of a package field definition, this
5489 identifier resolves to the package being defined.
5491 The example below shows how to add a package as a native input of itself when
5499 ;; When cross-compiled, Guile, for example, depends on
5500 ;; a native version of itself. Add it here.
5501 (native-inputs (if (%current-target-system)
5502 `(("self" ,this-package))
5506 It is an error to refer to @code{this-package} outside a package definition.
5509 @node origin Reference
5510 @subsection @code{origin} Reference
5512 This section summarizes all the options available in @code{origin}
5513 declarations (@pxref{Defining Packages}).
5515 @deftp {Data Type} origin
5516 This is the data type representing a source code origin.
5520 An object containing the URI of the source. The object type depends on
5521 the @code{method} (see below). For example, when using the
5522 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5523 values are: a URL represented as a string, or a list thereof.
5526 A procedure that handles the URI.
5531 @item @var{url-fetch} from @code{(guix download)}
5532 download a file from the HTTP, HTTPS, or FTP URL specified in the
5536 @item @var{git-fetch} from @code{(guix git-download)}
5537 clone the Git version control repository, and check out the revision
5538 specified in the @code{uri} field as a @code{git-reference} object; a
5539 @code{git-reference} looks like this:
5543 (url "git://git.debian.org/git/pkg-shadow/shadow")
5544 (commit "v4.1.5.1"))
5549 A bytevector containing the SHA-256 hash of the source. Typically the
5550 @code{base32} form is used here to generate the bytevector from a
5553 You can obtain this information using @code{guix download}
5554 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5557 @item @code{file-name} (default: @code{#f})
5558 The file name under which the source code should be saved. When this is
5559 @code{#f}, a sensible default value will be used in most cases. In case
5560 the source is fetched from a URL, the file name from the URL will be
5561 used. For version control checkouts, it is recommended to provide the
5562 file name explicitly because the default is not very descriptive.
5564 @item @code{patches} (default: @code{'()})
5565 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5566 file-like objects}) pointing to patches to be applied to the source.
5568 This list of patches must be unconditional. In particular, it cannot
5569 depend on the value of @code{%current-system} or
5570 @code{%current-target-system}.
5572 @item @code{snippet} (default: @code{#f})
5573 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5574 in the source directory. This is a convenient way to modify the source,
5575 sometimes more convenient than a patch.
5577 @item @code{patch-flags} (default: @code{'("-p1")})
5578 A list of command-line flags that should be passed to the @code{patch}
5581 @item @code{patch-inputs} (default: @code{#f})
5582 Input packages or derivations to the patching process. When this is
5583 @code{#f}, the usual set of inputs necessary for patching are provided,
5584 such as GNU@tie{}Patch.
5586 @item @code{modules} (default: @code{'()})
5587 A list of Guile modules that should be loaded during the patching
5588 process and while running the code in the @code{snippet} field.
5590 @item @code{patch-guile} (default: @code{#f})
5591 The Guile package that should be used in the patching process. When
5592 this is @code{#f}, a sensible default is used.
5598 @section Build Systems
5600 @cindex build system
5601 Each package definition specifies a @dfn{build system} and arguments for
5602 that build system (@pxref{Defining Packages}). This @code{build-system}
5603 field represents the build procedure of the package, as well as implicit
5604 dependencies of that build procedure.
5606 Build systems are @code{<build-system>} objects. The interface to
5607 create and manipulate them is provided by the @code{(guix build-system)}
5608 module, and actual build systems are exported by specific modules.
5610 @cindex bag (low-level package representation)
5611 Under the hood, build systems first compile package objects to
5612 @dfn{bags}. A @dfn{bag} is like a package, but with less
5613 ornamentation---in other words, a bag is a lower-level representation of
5614 a package, which includes all the inputs of that package, including some
5615 that were implicitly added by the build system. This intermediate
5616 representation is then compiled to a derivation (@pxref{Derivations}).
5618 Build systems accept an optional list of @dfn{arguments}. In package
5619 definitions, these are passed @i{via} the @code{arguments} field
5620 (@pxref{Defining Packages}). They are typically keyword arguments
5621 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5622 Guile Reference Manual}). The value of these arguments is usually
5623 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5624 by the daemon (@pxref{Derivations}).
5626 The main build system is @var{gnu-build-system}, which implements the
5627 standard build procedure for GNU and many other packages. It
5628 is provided by the @code{(guix build-system gnu)} module.
5630 @defvr {Scheme Variable} gnu-build-system
5631 @var{gnu-build-system} represents the GNU Build System, and variants
5632 thereof (@pxref{Configuration, configuration and makefile conventions,,
5633 standards, GNU Coding Standards}).
5635 @cindex build phases
5636 In a nutshell, packages using it are configured, built, and installed with
5637 the usual @code{./configure && make && make check && make install}
5638 command sequence. In practice, a few additional steps are often needed.
5639 All these steps are split up in separate @dfn{phases},
5640 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5641 modules for more details about the build phases.}:
5645 Unpack the source tarball, and change the current directory to the
5646 extracted source tree. If the source is actually a directory, copy it
5647 to the build tree, and enter that directory.
5649 @item patch-source-shebangs
5650 Patch shebangs encountered in source files so they refer to the right
5651 store file names. For instance, this changes @code{#!/bin/sh} to
5652 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
5655 Run the @file{configure} script with a number of default options, such
5656 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
5657 by the @code{#:configure-flags} argument.
5660 Run @code{make} with the list of flags specified with
5661 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
5662 (the default), build with @code{make -j}.
5665 Run @code{make check}, or some other target specified with
5666 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
5667 @code{#:parallel-tests?} argument is true (the default), run @code{make
5671 Run @code{make install} with the flags listed in @code{#:make-flags}.
5673 @item patch-shebangs
5674 Patch shebangs on the installed executable files.
5677 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
5678 is false), copying them to the @code{debug} output when available
5679 (@pxref{Installing Debugging Files}).
5682 @vindex %standard-phases
5683 The build-side module @code{(guix build gnu-build-system)} defines
5684 @var{%standard-phases} as the default list of build phases.
5685 @var{%standard-phases} is a list of symbol/procedure pairs, where the
5686 procedure implements the actual phase.
5688 The list of phases used for a particular package can be changed with the
5689 @code{#:phases} parameter. For instance, passing:
5692 #:phases (modify-phases %standard-phases (delete 'configure))
5695 means that all the phases described above will be used, except the
5696 @code{configure} phase.
5698 In addition, this build system ensures that the ``standard'' environment
5699 for GNU packages is available. This includes tools such as GCC, libc,
5700 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
5701 build-system gnu)} module for a complete list). We call these the
5702 @dfn{implicit inputs} of a package, because package definitions do not
5703 have to mention them.
5706 Other @code{<build-system>} objects are defined to support other
5707 conventions and tools used by free software packages. They inherit most
5708 of @var{gnu-build-system}, and differ mainly in the set of inputs
5709 implicitly added to the build process, and in the list of phases
5710 executed. Some of these build systems are listed below.
5712 @defvr {Scheme Variable} ant-build-system
5713 This variable is exported by @code{(guix build-system ant)}. It
5714 implements the build procedure for Java packages that can be built with
5715 @url{https://ant.apache.org/, Ant build tool}.
5717 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
5718 provided by the @code{icedtea} package to the set of inputs. Different
5719 packages can be specified with the @code{#:ant} and @code{#:jdk}
5720 parameters, respectively.
5722 When the original package does not provide a suitable Ant build file,
5723 the parameter @code{#:jar-name} can be used to generate a minimal Ant
5724 build file @file{build.xml} with tasks to build the specified jar
5725 archive. In this case the parameter @code{#:source-dir} can be used to
5726 specify the source sub-directory, defaulting to ``src''.
5728 The @code{#:main-class} parameter can be used with the minimal ant
5729 buildfile to specify the main class of the resulting jar. This makes the
5730 jar file executable. The @code{#:test-include} parameter can be used to
5731 specify the list of junit tests to run. It defaults to
5732 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
5733 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
5734 because abstract classes cannot be run as tests.
5736 The parameter @code{#:build-target} can be used to specify the Ant task
5737 that should be run during the @code{build} phase. By default the
5738 ``jar'' task will be run.
5742 @defvr {Scheme Variable} android-ndk-build-system
5743 @cindex Android distribution
5744 @cindex Android NDK build system
5745 This variable is exported by @code{(guix build-system android-ndk)}. It
5746 implements a build procedure for Android NDK (native development kit)
5747 packages using a Guix-specific build process.
5749 The build system assumes that packages install their public interface
5750 (header) files to the subdirectory "include" of the "out" output and
5751 their libraries to the subdirectory "lib" of the "out" output.
5753 It's also assumed that the union of all the dependencies of a package
5754 has no conflicting files.
5756 For the time being, cross-compilation is not supported - so right now
5757 the libraries and header files are assumed to be host tools.
5761 @defvr {Scheme Variable} asdf-build-system/source
5762 @defvrx {Scheme Variable} asdf-build-system/sbcl
5763 @defvrx {Scheme Variable} asdf-build-system/ecl
5765 These variables, exported by @code{(guix build-system asdf)}, implement
5766 build procedures for Common Lisp packages using
5767 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
5768 definition facility for Common Lisp programs and libraries.
5770 The @code{asdf-build-system/source} system installs the packages in
5771 source form, and can be loaded using any common lisp implementation, via
5772 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
5773 systems in the format which a particular implementation understands.
5774 These build systems can also be used to produce executable programs, or
5775 lisp images which contain a set of packages pre-loaded.
5777 The build system uses naming conventions. For binary packages, the
5778 package name should be prefixed with the lisp implementation, such as
5779 @code{sbcl-} for @code{asdf-build-system/sbcl}.
5781 Additionally, the corresponding source package should be labeled using
5782 the same convention as python packages (see @ref{Python Modules}), using
5783 the @code{cl-} prefix.
5785 For binary packages, each system should be defined as a Guix package.
5786 If one package @code{origin} contains several systems, package variants
5787 can be created in order to build all the systems. Source packages,
5788 which use @code{asdf-build-system/source}, may contain several systems.
5790 In order to create executable programs and images, the build-side
5791 procedures @code{build-program} and @code{build-image} can be used.
5792 They should be called in a build phase after the @code{create-symlinks}
5793 phase, so that the system which was just built can be used within the
5794 resulting image. @code{build-program} requires a list of Common Lisp
5795 expressions to be passed as the @code{#:entry-program} argument.
5797 If the system is not defined within its own @code{.asd} file of the same
5798 name, then the @code{#:asd-file} parameter should be used to specify
5799 which file the system is defined in. Furthermore, if the package
5800 defines a system for its tests in a separate file, it will be loaded
5801 before the tests are run if it is specified by the
5802 @code{#:test-asd-file} parameter. If it is not set, the files
5803 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
5804 and @code{test.asd} will be tried if they exist.
5806 If for some reason the package must be named in a different way than the
5807 naming conventions suggest, the @code{#:asd-system-name} parameter can
5808 be used to specify the name of the system.
5812 @defvr {Scheme Variable} cargo-build-system
5813 @cindex Rust programming language
5814 @cindex Cargo (Rust build system)
5815 This variable is exported by @code{(guix build-system cargo)}. It
5816 supports builds of packages using Cargo, the build tool of the
5817 @uref{https://www.rust-lang.org, Rust programming language}.
5819 It adds @code{rustc} and @code{cargo} to the set of inputs.
5820 A different Rust package can be specified with the @code{#:rust} parameter.
5822 Regular cargo dependencies should be added to the package definition via the
5823 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
5824 spec can be a package or a source definition. Note that the spec must
5825 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
5826 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
5827 should be added to the package definition via the
5828 @code{#:cargo-development-inputs} parameter.
5830 In its @code{configure} phase, this build system will make any source inputs
5831 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
5832 parameters available to cargo. The @code{install} phase installs any crate
5833 the binaries if they are defined by the crate.
5836 @cindex Clojure (programming language)
5837 @cindex simple Clojure build system
5838 @defvr {Scheme Variable} clojure-build-system
5839 This variable is exported by @code{(guix build-system clojure)}. It implements
5840 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
5841 using plain old @code{compile} in Clojure. Cross-compilation is not supported
5844 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
5845 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
5846 @code{#:zip} parameters, respectively.
5848 A list of source directories, test directories and jar names can be specified
5849 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
5850 parameters, respectively. Compile directory and main class can be specified
5851 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
5852 Other parameters are documented below.
5854 This build system is an extension of @var{ant-build-system}, but with the
5855 following phases changed:
5860 This phase calls @code{compile} in Clojure to compile source files and runs
5861 @command{jar} to create jars from both source files and compiled files
5862 according to the include list and exclude list specified in
5863 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
5864 has priority over the include list. These lists consist of symbols
5865 representing Clojure libraries or the special keyword @code{#:all} representing
5866 all Clojure libraries found under the source directories. The parameter
5867 @code{#:omit-source?} decides if source should be included into the jars.
5870 This phase runs tests according to the include list and exclude list specified
5871 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
5872 meanings are analogous to that of @code{#:aot-include} and
5873 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
5874 stands for all Clojure libraries found under the test directories. The
5875 parameter @code{#:tests?} decides if tests should be run.
5878 This phase installs all jars built previously.
5881 Apart from the above, this build system also contains an additional phase:
5886 This phase installs all top-level files with base name matching
5887 @var{%doc-regex}. A different regex can be specified with the
5888 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
5889 directories specified in @code{#:doc-dirs} are installed as well.
5893 @defvr {Scheme Variable} cmake-build-system
5894 This variable is exported by @code{(guix build-system cmake)}. It
5895 implements the build procedure for packages using the
5896 @url{https://www.cmake.org, CMake build tool}.
5898 It automatically adds the @code{cmake} package to the set of inputs.
5899 Which package is used can be specified with the @code{#:cmake}
5902 The @code{#:configure-flags} parameter is taken as a list of flags
5903 passed to the @command{cmake} command. The @code{#:build-type}
5904 parameter specifies in abstract terms the flags passed to the compiler;
5905 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
5906 debugging information''), which roughly means that code is compiled with
5907 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
5910 @defvr {Scheme Variable} dune-build-system
5911 This variable is exported by @code{(guix build-system dune)}. It
5912 supports builds of packages using @uref{https://dune.build/, Dune}, a build
5913 tool for the OCaml programming language. It is implemented as an extension
5914 of the @code{ocaml-build-system} which is described below. As such, the
5915 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
5918 It automatically adds the @code{dune} package to the set of inputs.
5919 Which package is used can be specified with the @code{#:dune}
5922 There is no @code{configure} phase because dune packages typically don't
5923 need to be configured. The @code{#:build-flags} parameter is taken as a
5924 list of flags passed to the @code{dune} command during the build.
5926 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
5927 command instead of the more recent @code{dune} command while building
5928 a package. Its default value is @code{#f}.
5930 The @code{#:package} parameter can be passed to specify a package name, which
5931 is useful when a package contains multiple packages and you want to build
5932 only one of them. This is equivalent to passing the @code{-p} argument to
5936 @defvr {Scheme Variable} go-build-system
5937 This variable is exported by @code{(guix build-system go)}. It
5938 implements a build procedure for Go packages using the standard
5939 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
5940 Go build mechanisms}.
5942 The user is expected to provide a value for the key @code{#:import-path}
5943 and, in some cases, @code{#:unpack-path}. The
5944 @url{https://golang.org/doc/code.html#ImportPaths, import path}
5945 corresponds to the file system path expected by the package's build
5946 scripts and any referring packages, and provides a unique way to
5947 refer to a Go package. It is typically based on a combination of the
5948 package source code's remote URI and file system hierarchy structure. In
5949 some cases, you will need to unpack the package's source code to a
5950 different directory structure than the one indicated by the import path,
5951 and @code{#:unpack-path} should be used in such cases.
5953 Packages that provide Go libraries should install their source code into
5954 the built output. The key @code{#:install-source?}, which defaults to
5955 @code{#t}, controls whether or not the source code is installed. It can
5956 be set to @code{#f} for packages that only provide executable files.
5959 @defvr {Scheme Variable} glib-or-gtk-build-system
5960 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
5961 is intended for use with packages making use of GLib or GTK+.
5963 This build system adds the following two phases to the ones defined by
5964 @var{gnu-build-system}:
5967 @item glib-or-gtk-wrap
5968 The phase @code{glib-or-gtk-wrap} ensures that programs in
5969 @file{bin/} are able to find GLib ``schemas'' and
5970 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
5971 modules}. This is achieved by wrapping the programs in launch scripts
5972 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
5973 environment variables.
5975 It is possible to exclude specific package outputs from that wrapping
5976 process by listing their names in the
5977 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
5978 when an output is known not to contain any GLib or GTK+ binaries, and
5979 where wrapping would gratuitously add a dependency of that output on
5982 @item glib-or-gtk-compile-schemas
5983 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
5984 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
5985 GSettings schemas} of GLib are compiled. Compilation is performed by the
5986 @command{glib-compile-schemas} program. It is provided by the package
5987 @code{glib:bin} which is automatically imported by the build system.
5988 The @code{glib} package providing @command{glib-compile-schemas} can be
5989 specified with the @code{#:glib} parameter.
5992 Both phases are executed after the @code{install} phase.
5995 @defvr {Scheme Variable} guile-build-system
5996 This build system is for Guile packages that consist exclusively of Scheme
5997 code and that are so lean that they don't even have a makefile, let alone a
5998 @file{configure} script. It compiles Scheme code using @command{guild
5999 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6000 installs the @file{.scm} and @file{.go} files in the right place. It also
6001 installs documentation.
6003 This build system supports cross-compilation by using the @code{--target}
6004 option of @command{guild compile}.
6006 Packages built with @code{guile-build-system} must provide a Guile package in
6007 their @code{native-inputs} field.
6010 @defvr {Scheme Variable} minify-build-system
6011 This variable is exported by @code{(guix build-system minify)}. It
6012 implements a minification procedure for simple JavaScript packages.
6014 It adds @code{uglify-js} to the set of inputs and uses it to compress
6015 all JavaScript files in the @file{src} directory. A different minifier
6016 package can be specified with the @code{#:uglify-js} parameter, but it
6017 is expected that the package writes the minified code to the standard
6020 When the input JavaScript files are not all located in the @file{src}
6021 directory, the parameter @code{#:javascript-files} can be used to
6022 specify a list of file names to feed to the minifier.
6025 @defvr {Scheme Variable} ocaml-build-system
6026 This variable is exported by @code{(guix build-system ocaml)}. It implements
6027 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6028 of choosing the correct set of commands to run for each package. OCaml
6029 packages can expect many different commands to be run. This build system will
6032 When the package has a @file{setup.ml} file present at the top-level, it will
6033 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6034 @code{ocaml setup.ml -install}. The build system will assume that this file
6035 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6036 care of setting the prefix and enabling tests if they are not disabled. You
6037 can pass configure and build flags with the @code{#:configure-flags} and
6038 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6039 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6040 bypass this system in the build and install phases.
6042 When the package has a @file{configure} file, it is assumed that it is a
6043 hand-made configure script that requires a different argument format than
6044 in the @code{gnu-build-system}. You can add more flags with the
6045 @code{#:configure-flags} key.
6047 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6048 @code{#t}), it will be used and more flags can be passed to the build and
6049 install phases with the @code{#:make-flags} key.
6051 Finally, some packages do not have these files and use a somewhat standard
6052 location for its build system. In that case, the build system will run
6053 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6054 providing the path to the required findlib module. Additional flags can
6055 be passed via the @code{#:build-flags} key. Install is taken care of by
6056 @command{opam-installer}. In this case, the @code{opam} package must
6057 be added to the @code{native-inputs} field of the package definition.
6059 Note that most OCaml packages assume they will be installed in the same
6060 directory as OCaml, which is not what we want in guix. In particular, they
6061 will install @file{.so} files in their module's directory, which is usually
6062 fine because it is in the OCaml compiler directory. In guix though, these
6063 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6064 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6065 @file{.so} libraries should be installed.
6068 @defvr {Scheme Variable} python-build-system
6069 This variable is exported by @code{(guix build-system python)}. It
6070 implements the more or less standard build procedure used by Python
6071 packages, which consists in running @code{python setup.py build} and
6072 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6074 For packages that install stand-alone Python programs under @code{bin/},
6075 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6076 environment variable points to all the Python libraries they depend on.
6078 Which Python package is used to perform the build can be specified with
6079 the @code{#:python} parameter. This is a useful way to force a package
6080 to be built for a specific version of the Python interpreter, which
6081 might be necessary if the package is only compatible with a single
6082 interpreter version.
6084 By default guix calls @code{setup.py} under control of
6085 @code{setuptools}, much like @command{pip} does. Some packages are not
6086 compatible with setuptools (and pip), thus you can disable this by
6087 setting the @code{#:use-setuptools} parameter to @code{#f}.
6090 @defvr {Scheme Variable} perl-build-system
6091 This variable is exported by @code{(guix build-system perl)}. It
6092 implements the standard build procedure for Perl packages, which either
6093 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6094 followed by @code{Build} and @code{Build install}; or in running
6095 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6096 @code{make} and @code{make install}, depending on which of
6097 @code{Build.PL} or @code{Makefile.PL} is present in the package
6098 distribution. Preference is given to the former if both @code{Build.PL}
6099 and @code{Makefile.PL} exist in the package distribution. This
6100 preference can be reversed by specifying @code{#t} for the
6101 @code{#:make-maker?} parameter.
6103 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6104 passes flags specified by the @code{#:make-maker-flags} or
6105 @code{#:module-build-flags} parameter, respectively.
6107 Which Perl package is used can be specified with @code{#:perl}.
6110 @defvr {Scheme Variable} r-build-system
6111 This variable is exported by @code{(guix build-system r)}. It
6112 implements the build procedure used by @uref{https://r-project.org, R}
6113 packages, which essentially is little more than running @code{R CMD
6114 INSTALL --library=/gnu/store/@dots{}} in an environment where
6115 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6116 are run after installation using the R function
6117 @code{tools::testInstalledPackage}.
6120 @defvr {Scheme Variable} rakudo-build-system
6121 This variable is exported by @code{(guix build-system rakudo)}. It
6122 implements the build procedure used by @uref{https://rakudo.org/,
6123 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6124 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6125 installs the binaries, library files and the resources, as well as wrap
6126 the files under the @code{bin/} directory. Tests can be skipped by
6127 passing @code{#f} to the @code{tests?} parameter.
6129 Which rakudo package is used can be specified with @code{rakudo}.
6130 Which perl6-tap-harness package used for the tests can be specified with
6131 @code{#:prove6} or removed by passing @code{#f} to the
6132 @code{with-prove6?} parameter.
6133 Which perl6-zef package used for tests and installing can be specified
6134 with @code{#:zef} or removed by passing @code{#f} to the
6135 @code{with-zef?} parameter.
6138 @defvr {Scheme Variable} texlive-build-system
6139 This variable is exported by @code{(guix build-system texlive)}. It is
6140 used to build TeX packages in batch mode with a specified engine. The
6141 build system sets the @code{TEXINPUTS} variable to find all TeX source
6142 files in the inputs.
6144 By default it runs @code{luatex} on all files ending on @code{ins}. A
6145 different engine and format can be specified with the
6146 @code{#:tex-format} argument. Different build targets can be specified
6147 with the @code{#:build-targets} argument, which expects a list of file
6148 names. The build system adds only @code{texlive-bin} and
6149 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6150 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6151 and @code{#:texlive-latex-base}, respectively.
6153 The @code{#:tex-directory} parameter tells the build system where to
6154 install the built files under the texmf tree.
6157 @defvr {Scheme Variable} ruby-build-system
6158 This variable is exported by @code{(guix build-system ruby)}. It
6159 implements the RubyGems build procedure used by Ruby packages, which
6160 involves running @code{gem build} followed by @code{gem install}.
6162 The @code{source} field of a package that uses this build system
6163 typically references a gem archive, since this is the format that Ruby
6164 developers use when releasing their software. The build system unpacks
6165 the gem archive, potentially patches the source, runs the test suite,
6166 repackages the gem, and installs it. Additionally, directories and
6167 tarballs may be referenced to allow building unreleased gems from Git or
6168 a traditional source release tarball.
6170 Which Ruby package is used can be specified with the @code{#:ruby}
6171 parameter. A list of additional flags to be passed to the @command{gem}
6172 command can be specified with the @code{#:gem-flags} parameter.
6175 @defvr {Scheme Variable} waf-build-system
6176 This variable is exported by @code{(guix build-system waf)}. It
6177 implements a build procedure around the @code{waf} script. The common
6178 phases---@code{configure}, @code{build}, and @code{install}---are
6179 implemented by passing their names as arguments to the @code{waf}
6182 The @code{waf} script is executed by the Python interpreter. Which
6183 Python package is used to run the script can be specified with the
6184 @code{#:python} parameter.
6187 @defvr {Scheme Variable} scons-build-system
6188 This variable is exported by @code{(guix build-system scons)}. It
6189 implements the build procedure used by the SCons software construction
6190 tool. This build system runs @code{scons} to build the package,
6191 @code{scons test} to run tests, and then @code{scons install} to install
6194 Additional flags to be passed to @code{scons} can be specified with the
6195 @code{#:scons-flags} parameter. The version of Python used to run SCons
6196 can be specified by selecting the appropriate SCons package with the
6197 @code{#:scons} parameter.
6200 @defvr {Scheme Variable} haskell-build-system
6201 This variable is exported by @code{(guix build-system haskell)}. It
6202 implements the Cabal build procedure used by Haskell packages, which
6203 involves running @code{runhaskell Setup.hs configure
6204 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6205 Instead of installing the package by running @code{runhaskell Setup.hs
6206 install}, to avoid trying to register libraries in the read-only
6207 compiler store directory, the build system uses @code{runhaskell
6208 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6209 addition, the build system generates the package documentation by
6210 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6211 is passed. Optional Haddock parameters can be passed with the help of
6212 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6213 not found, the build system looks for @code{Setup.lhs} instead.
6215 Which Haskell compiler is used can be specified with the @code{#:haskell}
6216 parameter which defaults to @code{ghc}.
6219 @defvr {Scheme Variable} dub-build-system
6220 This variable is exported by @code{(guix build-system dub)}. It
6221 implements the Dub build procedure used by D packages, which
6222 involves running @code{dub build} and @code{dub run}.
6223 Installation is done by copying the files manually.
6225 Which D compiler is used can be specified with the @code{#:ldc}
6226 parameter which defaults to @code{ldc}.
6229 @defvr {Scheme Variable} emacs-build-system
6230 This variable is exported by @code{(guix build-system emacs)}. It
6231 implements an installation procedure similar to the packaging system
6232 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6234 It first creates the @code{@var{package}-autoloads.el} file, then it
6235 byte compiles all Emacs Lisp files. Differently from the Emacs
6236 packaging system, the Info documentation files are moved to the standard
6237 documentation directory and the @file{dir} file is deleted. Each
6238 package is installed in its own directory under
6239 @file{share/emacs/site-lisp/guix.d}.
6242 @defvr {Scheme Variable} font-build-system
6243 This variable is exported by @code{(guix build-system font)}. It
6244 implements an installation procedure for font packages where upstream
6245 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6246 need to be copied into place. It copies font files to standard
6247 locations in the output directory.
6250 @defvr {Scheme Variable} meson-build-system
6251 This variable is exported by @code{(guix build-system meson)}. It
6252 implements the build procedure for packages that use
6253 @url{https://mesonbuild.com, Meson} as their build system.
6255 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6256 of inputs, and they can be changed with the parameters @code{#:meson}
6257 and @code{#:ninja} if needed. The default Meson is
6258 @code{meson-for-build}, which is special because it doesn't clear the
6259 @code{RUNPATH} of binaries and libraries when they are installed.
6261 This build system is an extension of @var{gnu-build-system}, but with the
6262 following phases changed to some specific for Meson:
6267 The phase runs @code{meson} with the flags specified in
6268 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6269 @code{plain} unless something else is specified in @code{#:build-type}.
6272 The phase runs @code{ninja} to build the package in parallel by default, but
6273 this can be changed with @code{#:parallel-build?}.
6276 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6277 which is @code{"test"} by default.
6280 The phase runs @code{ninja install} and can not be changed.
6283 Apart from that, the build system also adds the following phases:
6288 This phase ensures that all binaries can find the libraries they need.
6289 It searches for required libraries in subdirectories of the package being
6290 built, and adds those to @code{RUNPATH} where needed. It also removes
6291 references to libraries left over from the build phase by
6292 @code{meson-for-build}, such as test dependencies, that aren't actually
6293 required for the program to run.
6295 @item glib-or-gtk-wrap
6296 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6297 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6299 @item glib-or-gtk-compile-schemas
6300 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6301 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6305 @defvr {Scheme Variable} linux-module-build-system
6306 @var{linux-module-build-system} allows building Linux kernel modules.
6308 @cindex build phases
6309 This build system is an extension of @var{gnu-build-system}, but with the
6310 following phases changed:
6315 This phase configures the environment so that the Linux kernel's Makefile
6316 can be used to build the external kernel module.
6319 This phase uses the Linux kernel's Makefile in order to build the external
6323 This phase uses the Linux kernel's Makefile in order to install the external
6327 It is possible and useful to specify the Linux kernel to use for building
6328 the module (in the "arguments" form of a package using the
6329 linux-module-build-system, use the key #:linux to specify it).
6332 Lastly, for packages that do not need anything as sophisticated, a
6333 ``trivial'' build system is provided. It is trivial in the sense that
6334 it provides basically no support: it does not pull any implicit inputs,
6335 and does not have a notion of build phases.
6337 @defvr {Scheme Variable} trivial-build-system
6338 This variable is exported by @code{(guix build-system trivial)}.
6340 This build system requires a @code{#:builder} argument. This argument
6341 must be a Scheme expression that builds the package output(s)---as
6342 with @code{build-expression->derivation} (@pxref{Derivations,
6343 @code{build-expression->derivation}}).
6353 Conceptually, the @dfn{store} is the place where derivations that have
6354 been built successfully are stored---by default, @file{/gnu/store}.
6355 Sub-directories in the store are referred to as @dfn{store items} or
6356 sometimes @dfn{store paths}. The store has an associated database that
6357 contains information such as the store paths referred to by each store
6358 path, and the list of @emph{valid} store items---results of successful
6359 builds. This database resides in @file{@var{localstatedir}/guix/db},
6360 where @var{localstatedir} is the state directory specified @i{via}
6361 @option{--localstatedir} at configure time, usually @file{/var}.
6363 The store is @emph{always} accessed by the daemon on behalf of its clients
6364 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6365 connect to the daemon over a Unix-domain socket, send requests to it,
6366 and read the result---these are remote procedure calls, or RPCs.
6369 Users must @emph{never} modify files under @file{/gnu/store} directly.
6370 This would lead to inconsistencies and break the immutability
6371 assumptions of Guix's functional model (@pxref{Introduction}).
6373 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6374 how to check the integrity of the store and attempt recovery from
6375 accidental modifications.
6378 The @code{(guix store)} module provides procedures to connect to the
6379 daemon, and to perform RPCs. These are described below. By default,
6380 @code{open-connection}, and thus all the @command{guix} commands,
6381 connect to the local daemon or to the URI specified by the
6382 @code{GUIX_DAEMON_SOCKET} environment variable.
6384 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6385 When set, the value of this variable should be a file name or a URI
6386 designating the daemon endpoint. When it is a file name, it denotes a
6387 Unix-domain socket to connect to. In addition to file names, the
6388 supported URI schemes are:
6393 These are for Unix-domain sockets.
6394 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6395 @file{/var/guix/daemon-socket/socket}.
6398 @cindex daemon, remote access
6399 @cindex remote access to the daemon
6400 @cindex daemon, cluster setup
6401 @cindex clusters, daemon setup
6402 These URIs denote connections over TCP/IP, without encryption nor
6403 authentication of the remote host. The URI must specify the host name
6404 and optionally a port number (by default port 44146 is used):
6407 guix://master.guix.example.org:1234
6410 This setup is suitable on local networks, such as clusters, where only
6411 trusted nodes may connect to the build daemon at
6412 @code{master.guix.example.org}.
6414 The @code{--listen} option of @command{guix-daemon} can be used to
6415 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6419 @cindex SSH access to build daemons
6420 These URIs allow you to connect to a remote daemon over
6421 SSH@footnote{This feature requires Guile-SSH (@pxref{Requirements}).}.
6422 A typical URL might look like this:
6425 ssh://charlie@@guix.example.org:22
6428 As for @command{guix copy}, the usual OpenSSH client configuration files
6429 are honored (@pxref{Invoking guix copy}).
6432 Additional URI schemes may be supported in the future.
6434 @c XXX: Remove this note when the protocol incurs fewer round trips
6435 @c and when (guix derivations) no longer relies on file system access.
6437 The ability to connect to remote build daemons is considered
6438 experimental as of @value{VERSION}. Please get in touch with us to
6439 share any problems or suggestions you may have (@pxref{Contributing}).
6443 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6444 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6445 @var{reserve-space?} is true, instruct it to reserve a little bit of
6446 extra space on the file system so that the garbage collector can still
6447 operate should the disk become full. Return a server object.
6449 @var{file} defaults to @code{%default-socket-path}, which is the normal
6450 location given the options that were passed to @command{configure}.
6453 @deffn {Scheme Procedure} close-connection @var{server}
6454 Close the connection to @var{server}.
6457 @defvr {Scheme Variable} current-build-output-port
6458 This variable is bound to a SRFI-39 parameter, which refers to the port
6459 where build and error logs sent by the daemon should be written.
6462 Procedures that make RPCs all take a server object as their first
6465 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6466 @cindex invalid store items
6467 Return @code{#t} when @var{path} designates a valid store item and
6468 @code{#f} otherwise (an invalid item may exist on disk but still be
6469 invalid, for instance because it is the result of an aborted or failed
6472 A @code{&store-protocol-error} condition is raised if @var{path} is not
6473 prefixed by the store directory (@file{/gnu/store}).
6476 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6477 Add @var{text} under file @var{name} in the store, and return its store
6478 path. @var{references} is the list of store paths referred to by the
6479 resulting store path.
6482 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6484 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6485 file names, or derivation/output pairs, using the specified
6486 @var{mode}---@code{(build-mode normal)} by default.
6489 Note that the @code{(guix monads)} module provides a monad as well as
6490 monadic versions of the above procedures, with the goal of making it
6491 more convenient to work with code that accesses the store (@pxref{The
6495 @i{This section is currently incomplete.}
6498 @section Derivations
6501 Low-level build actions and the environment in which they are performed
6502 are represented by @dfn{derivations}. A derivation contains the
6503 following pieces of information:
6507 The outputs of the derivation---derivations produce at least one file or
6508 directory in the store, but may produce more.
6511 @cindex build-time dependencies
6512 @cindex dependencies, build-time
6513 The inputs of the derivations---i.e., its build-time dependencies---which may
6514 be other derivations or plain files in the store (patches, build scripts,
6518 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
6521 The file name of a build script in the store, along with the arguments
6525 A list of environment variables to be defined.
6529 @cindex derivation path
6530 Derivations allow clients of the daemon to communicate build actions to
6531 the store. They exist in two forms: as an in-memory representation,
6532 both on the client- and daemon-side, and as files in the store whose
6533 name end in @code{.drv}---these files are referred to as @dfn{derivation
6534 paths}. Derivations paths can be passed to the @code{build-derivations}
6535 procedure to perform the build actions they prescribe (@pxref{The
6538 @cindex fixed-output derivations
6539 Operations such as file downloads and version-control checkouts for
6540 which the expected content hash is known in advance are modeled as
6541 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
6542 of a fixed-output derivation are independent of its inputs---e.g., a
6543 source code download produces the same result regardless of the download
6544 method and tools being used.
6547 @cindex run-time dependencies
6548 @cindex dependencies, run-time
6549 The outputs of derivations---i.e., the build results---have a set of
6550 @dfn{references}, as reported by the @code{references} RPC or the
6551 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
6552 are the set of run-time dependencies of the build results. References are a
6553 subset of the inputs of the derivation; this subset is automatically computed
6554 by the build daemon by scanning all the files in the outputs.
6556 The @code{(guix derivations)} module provides a representation of
6557 derivations as Scheme objects, along with procedures to create and
6558 otherwise manipulate derivations. The lowest-level primitive to create
6559 a derivation is the @code{derivation} procedure:
6561 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
6562 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6563 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
6564 [#:system (%current-system)] [#:references-graphs #f] @
6565 [#:allowed-references #f] [#:disallowed-references #f] @
6566 [#:leaked-env-vars #f] [#:local-build? #f] @
6567 [#:substitutable? #t] [#:properties '()]
6568 Build a derivation with the given arguments, and return the resulting
6569 @code{<derivation>} object.
6571 When @var{hash} and @var{hash-algo} are given, a
6572 @dfn{fixed-output derivation} is created---i.e., one whose result is
6573 known in advance, such as a file download. If, in addition,
6574 @var{recursive?} is true, then that fixed output may be an executable
6575 file or a directory and @var{hash} must be the hash of an archive
6576 containing this output.
6578 When @var{references-graphs} is true, it must be a list of file
6579 name/store path pairs. In that case, the reference graph of each store
6580 path is exported in the build environment in the corresponding file, in
6581 a simple text format.
6583 When @var{allowed-references} is true, it must be a list of store items
6584 or outputs that the derivation's output may refer to. Likewise,
6585 @var{disallowed-references}, if true, must be a list of things the
6586 outputs may @emph{not} refer to.
6588 When @var{leaked-env-vars} is true, it must be a list of strings
6589 denoting environment variables that are allowed to ``leak'' from the
6590 daemon's environment to the build environment. This is only applicable
6591 to fixed-output derivations---i.e., when @var{hash} is true. The main
6592 use is to allow variables such as @code{http_proxy} to be passed to
6593 derivations that download files.
6595 When @var{local-build?} is true, declare that the derivation is not a
6596 good candidate for offloading and should rather be built locally
6597 (@pxref{Daemon Offload Setup}). This is the case for small derivations
6598 where the costs of data transfers would outweigh the benefits.
6600 When @var{substitutable?} is false, declare that substitutes of the
6601 derivation's output should not be used (@pxref{Substitutes}). This is
6602 useful, for instance, when building packages that capture details of the
6603 host CPU instruction set.
6605 @var{properties} must be an association list describing ``properties'' of the
6606 derivation. It is kept as-is, uninterpreted, in the derivation.
6610 Here's an example with a shell script as its builder, assuming
6611 @var{store} is an open connection to the daemon, and @var{bash} points
6612 to a Bash executable in the store:
6615 (use-modules (guix utils)
6619 (let ((builder ; add the Bash script to the store
6620 (add-text-to-store store "my-builder.sh"
6621 "echo hello world > $out\n" '())))
6622 (derivation store "foo"
6623 bash `("-e" ,builder)
6624 #:inputs `((,bash) (,builder))
6625 #:env-vars '(("HOME" . "/homeless"))))
6626 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
6629 As can be guessed, this primitive is cumbersome to use directly. A
6630 better approach is to write build scripts in Scheme, of course! The
6631 best course of action for that is to write the build code as a
6632 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
6633 information, @pxref{G-Expressions}.
6635 Once upon a time, @code{gexp->derivation} did not exist and constructing
6636 derivations with build code written in Scheme was achieved with
6637 @code{build-expression->derivation}, documented below. This procedure
6638 is now deprecated in favor of the much nicer @code{gexp->derivation}.
6640 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
6641 @var{name} @var{exp} @
6642 [#:system (%current-system)] [#:inputs '()] @
6643 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
6644 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
6645 [#:references-graphs #f] [#:allowed-references #f] @
6646 [#:disallowed-references #f] @
6647 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
6648 Return a derivation that executes Scheme expression @var{exp} as a
6649 builder for derivation @var{name}. @var{inputs} must be a list of
6650 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
6651 @code{"out"} is assumed. @var{modules} is a list of names of Guile
6652 modules from the current search path to be copied in the store,
6653 compiled, and made available in the load path during the execution of
6654 @var{exp}---e.g., @code{((guix build utils) (guix build
6655 gnu-build-system))}.
6657 @var{exp} is evaluated in an environment where @code{%outputs} is bound
6658 to a list of output/path pairs, and where @code{%build-inputs} is bound
6659 to a list of string/output-path pairs made from @var{inputs}.
6660 Optionally, @var{env-vars} is a list of string pairs specifying the name
6661 and value of environment variables visible to the builder. The builder
6662 terminates by passing the result of @var{exp} to @code{exit}; thus, when
6663 @var{exp} returns @code{#f}, the build is considered to have failed.
6665 @var{exp} is built using @var{guile-for-build} (a derivation). When
6666 @var{guile-for-build} is omitted or is @code{#f}, the value of the
6667 @code{%guile-for-build} fluid is used instead.
6669 See the @code{derivation} procedure for the meaning of
6670 @var{references-graphs}, @var{allowed-references},
6671 @var{disallowed-references}, @var{local-build?}, and
6672 @var{substitutable?}.
6676 Here's an example of a single-output derivation that creates a directory
6677 containing one file:
6680 (let ((builder '(let ((out (assoc-ref %outputs "out")))
6681 (mkdir out) ; create /gnu/store/@dots{}-goo
6682 (call-with-output-file (string-append out "/test")
6684 (display '(hello guix) p))))))
6685 (build-expression->derivation store "goo" builder))
6687 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
6691 @node The Store Monad
6692 @section The Store Monad
6696 The procedures that operate on the store described in the previous
6697 sections all take an open connection to the build daemon as their first
6698 argument. Although the underlying model is functional, they either have
6699 side effects or depend on the current state of the store.
6701 The former is inconvenient: the connection to the build daemon has to be
6702 carried around in all those functions, making it impossible to compose
6703 functions that do not take that parameter with functions that do. The
6704 latter can be problematic: since store operations have side effects
6705 and/or depend on external state, they have to be properly sequenced.
6707 @cindex monadic values
6708 @cindex monadic functions
6709 This is where the @code{(guix monads)} module comes in. This module
6710 provides a framework for working with @dfn{monads}, and a particularly
6711 useful monad for our uses, the @dfn{store monad}. Monads are a
6712 construct that allows two things: associating ``context'' with values
6713 (in our case, the context is the store), and building sequences of
6714 computations (here computations include accesses to the store). Values
6715 in a monad---values that carry this additional context---are called
6716 @dfn{monadic values}; procedures that return such values are called
6717 @dfn{monadic procedures}.
6719 Consider this ``normal'' procedure:
6722 (define (sh-symlink store)
6723 ;; Return a derivation that symlinks the 'bash' executable.
6724 (let* ((drv (package-derivation store bash))
6725 (out (derivation->output-path drv))
6726 (sh (string-append out "/bin/bash")))
6727 (build-expression->derivation store "sh"
6728 `(symlink ,sh %output))))
6731 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
6732 as a monadic function:
6735 (define (sh-symlink)
6736 ;; Same, but return a monadic value.
6737 (mlet %store-monad ((drv (package->derivation bash)))
6738 (gexp->derivation "sh"
6739 #~(symlink (string-append #$drv "/bin/bash")
6743 There are several things to note in the second version: the @code{store}
6744 parameter is now implicit and is ``threaded'' in the calls to the
6745 @code{package->derivation} and @code{gexp->derivation} monadic
6746 procedures, and the monadic value returned by @code{package->derivation}
6747 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
6749 As it turns out, the call to @code{package->derivation} can even be
6750 omitted since it will take place implicitly, as we will see later
6751 (@pxref{G-Expressions}):
6754 (define (sh-symlink)
6755 (gexp->derivation "sh"
6756 #~(symlink (string-append #$bash "/bin/bash")
6761 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
6762 @c for the funny quote.
6763 Calling the monadic @code{sh-symlink} has no effect. As someone once
6764 said, ``you exit a monad like you exit a building on fire: by running''.
6765 So, to exit the monad and get the desired effect, one must use
6766 @code{run-with-store}:
6769 (run-with-store (open-connection) (sh-symlink))
6770 @result{} /gnu/store/...-sh-symlink
6773 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
6774 new ``meta-commands'' to make it easier to deal with monadic procedures:
6775 @code{run-in-store}, and @code{enter-store-monad}. The former is used
6776 to ``run'' a single monadic value through the store:
6779 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
6780 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6783 The latter enters a recursive REPL, where all the return values are
6784 automatically run through the store:
6787 scheme@@(guile-user)> ,enter-store-monad
6788 store-monad@@(guile-user) [1]> (package->derivation hello)
6789 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
6790 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
6791 $3 = "/gnu/store/@dots{}-foo"
6792 store-monad@@(guile-user) [1]> ,q
6793 scheme@@(guile-user)>
6797 Note that non-monadic values cannot be returned in the
6798 @code{store-monad} REPL.
6800 The main syntactic forms to deal with monads in general are provided by
6801 the @code{(guix monads)} module and are described below.
6803 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
6804 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
6808 @deffn {Scheme Syntax} return @var{val}
6809 Return a monadic value that encapsulates @var{val}.
6812 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
6813 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
6814 procedures @var{mproc}@dots{}@footnote{This operation is commonly
6815 referred to as ``bind'', but that name denotes an unrelated procedure in
6816 Guile. Thus we use this somewhat cryptic symbol inherited from the
6817 Haskell language.}. There can be one @var{mproc} or several of them, as
6822 (with-monad %state-monad
6824 (lambda (x) (return (+ 1 x)))
6825 (lambda (x) (return (* 2 x)))))
6829 @result{} some-state
6833 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
6835 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
6837 Bind the variables @var{var} to the monadic values @var{mval} in
6838 @var{body}, which is a sequence of expressions. As with the bind
6839 operator, this can be thought of as ``unpacking'' the raw, non-monadic
6840 value ``contained'' in @var{mval} and making @var{var} refer to that
6841 raw, non-monadic value within the scope of the @var{body}. The form
6842 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
6843 @var{val}, as per @code{let}. The binding operations occur in sequence
6844 from left to right. The last expression of @var{body} must be a monadic
6845 expression, and its result will become the result of the @code{mlet} or
6846 @code{mlet*} when run in the @var{monad}.
6848 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
6849 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
6852 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
6853 Bind @var{mexp} and the following monadic expressions in sequence,
6854 returning the result of the last expression. Every expression in the
6855 sequence must be a monadic expression.
6857 This is akin to @code{mlet}, except that the return values of the
6858 monadic expressions are ignored. In that sense, it is analogous to
6859 @code{begin}, but applied to monadic expressions.
6862 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
6863 When @var{condition} is true, evaluate the sequence of monadic
6864 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6865 @var{condition} is false, return @code{*unspecified*} in the current
6866 monad. Every expression in the sequence must be a monadic expression.
6869 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
6870 When @var{condition} is false, evaluate the sequence of monadic
6871 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
6872 @var{condition} is true, return @code{*unspecified*} in the current
6873 monad. Every expression in the sequence must be a monadic expression.
6877 The @code{(guix monads)} module provides the @dfn{state monad}, which
6878 allows an additional value---the state---to be @emph{threaded} through
6879 monadic procedure calls.
6881 @defvr {Scheme Variable} %state-monad
6882 The state monad. Procedures in the state monad can access and change
6883 the state that is threaded.
6885 Consider the example below. The @code{square} procedure returns a value
6886 in the state monad. It returns the square of its argument, but also
6887 increments the current state value:
6891 (mlet %state-monad ((count (current-state)))
6892 (mbegin %state-monad
6893 (set-current-state (+ 1 count))
6896 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
6901 When ``run'' through @var{%state-monad}, we obtain that additional state
6902 value, which is the number of @code{square} calls.
6905 @deffn {Monadic Procedure} current-state
6906 Return the current state as a monadic value.
6909 @deffn {Monadic Procedure} set-current-state @var{value}
6910 Set the current state to @var{value} and return the previous state as a
6914 @deffn {Monadic Procedure} state-push @var{value}
6915 Push @var{value} to the current state, which is assumed to be a list,
6916 and return the previous state as a monadic value.
6919 @deffn {Monadic Procedure} state-pop
6920 Pop a value from the current state and return it as a monadic value.
6921 The state is assumed to be a list.
6924 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
6925 Run monadic value @var{mval} starting with @var{state} as the initial
6926 state. Return two values: the resulting value, and the resulting state.
6929 The main interface to the store monad, provided by the @code{(guix
6930 store)} module, is as follows.
6932 @defvr {Scheme Variable} %store-monad
6933 The store monad---an alias for @var{%state-monad}.
6935 Values in the store monad encapsulate accesses to the store. When its
6936 effect is needed, a value of the store monad must be ``evaluated'' by
6937 passing it to the @code{run-with-store} procedure (see below.)
6940 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
6941 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
6942 open store connection.
6945 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
6946 Return as a monadic value the absolute file name in the store of the file
6947 containing @var{text}, a string. @var{references} is a list of store items that the
6948 resulting text file refers to; it defaults to the empty list.
6951 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
6952 Return as a monadic value the absolute file name in the store of the file
6953 containing @var{data}, a bytevector. @var{references} is a list of store
6954 items that the resulting binary file refers to; it defaults to the empty list.
6957 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
6958 [#:recursive? #t] [#:select? (const #t)]
6959 Return the name of @var{file} once interned in the store. Use
6960 @var{name} as its store name, or the basename of @var{file} if
6961 @var{name} is omitted.
6963 When @var{recursive?} is true, the contents of @var{file} are added
6964 recursively; if @var{file} designates a flat file and @var{recursive?}
6965 is true, its contents are added, and its permission bits are kept.
6967 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
6968 @var{stat})} for each directory entry, where @var{file} is the entry's
6969 absolute file name and @var{stat} is the result of @code{lstat}; exclude
6970 entries for which @var{select?} does not return true.
6972 The example below adds a file to the store, under two different names:
6975 (run-with-store (open-connection)
6976 (mlet %store-monad ((a (interned-file "README"))
6977 (b (interned-file "README" "LEGU-MIN")))
6978 (return (list a b))))
6980 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
6985 The @code{(guix packages)} module exports the following package-related
6988 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
6989 [#:system (%current-system)] [#:target #f] @
6992 value in the absolute file name of @var{file} within the @var{output}
6993 directory of @var{package}. When @var{file} is omitted, return the name
6994 of the @var{output} directory of @var{package}. When @var{target} is
6995 true, use it as a cross-compilation target triplet.
6998 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
6999 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7000 @var{target} [@var{system}]
7001 Monadic version of @code{package-derivation} and
7002 @code{package-cross-derivation} (@pxref{Defining Packages}).
7007 @section G-Expressions
7009 @cindex G-expression
7010 @cindex build code quoting
7011 So we have ``derivations'', which represent a sequence of build actions
7012 to be performed to produce an item in the store (@pxref{Derivations}).
7013 These build actions are performed when asking the daemon to actually
7014 build the derivations; they are run by the daemon in a container
7015 (@pxref{Invoking guix-daemon}).
7017 @cindex strata of code
7018 It should come as no surprise that we like to write these build actions
7019 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7020 code@footnote{The term @dfn{stratum} in this context was coined by
7021 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7022 Kiselyov, who has written insightful
7023 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7024 on this topic}, refers to this kind of code generation as
7025 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7026 to the daemon, etc.---and the ``build code''---code that actually
7027 performs build actions, such as making directories, invoking
7028 @command{make}, etc.
7030 To describe a derivation and its build actions, one typically needs to
7031 embed build code inside host code. It boils down to manipulating build
7032 code as data, and the homoiconicity of Scheme---code has a direct
7033 representation as data---comes in handy for that. But we need more than
7034 the normal @code{quasiquote} mechanism in Scheme to construct build
7037 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7038 S-expressions adapted to build expressions. G-expressions, or
7039 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7040 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7041 @code{#$}, and @code{#$@@}), which are comparable to
7042 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7043 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7044 GNU Guile Reference Manual}). However, there are major differences:
7048 Gexps are meant to be written to a file and run or manipulated by other
7052 When a high-level object such as a package or derivation is unquoted
7053 inside a gexp, the result is as if its output file name had been
7057 Gexps carry information about the packages or derivations they refer to,
7058 and these dependencies are automatically added as inputs to the build
7059 processes that use them.
7062 @cindex lowering, of high-level objects in gexps
7063 This mechanism is not limited to package and derivation
7064 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7065 derivations or files in the store can be defined,
7066 such that these objects can also be inserted
7067 into gexps. For example, a useful type of high-level objects that can be
7068 inserted in a gexp is ``file-like objects'', which make it easy to
7069 add files to the store and to refer to them in
7070 derivations and such (see @code{local-file} and @code{plain-file}
7073 To illustrate the idea, here is an example of a gexp:
7080 (symlink (string-append #$coreutils "/bin/ls")
7084 This gexp can be passed to @code{gexp->derivation}; we obtain a
7085 derivation that builds a directory containing exactly one symlink to
7086 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7089 (gexp->derivation "the-thing" build-exp)
7092 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7093 substituted to the reference to the @var{coreutils} package in the
7094 actual build code, and @var{coreutils} is automatically made an input to
7095 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7096 output)}) is replaced by a string containing the directory name of the
7097 output of the derivation.
7099 @cindex cross compilation
7100 In a cross-compilation context, it is useful to distinguish between
7101 references to the @emph{native} build of a package---that can run on the
7102 host---versus references to cross builds of a package. To that end, the
7103 @code{#+} plays the same role as @code{#$}, but is a reference to a
7104 native package build:
7107 (gexp->derivation "vi"
7110 (system* (string-append #+coreutils "/bin/ln")
7112 (string-append #$emacs "/bin/emacs")
7113 (string-append #$output "/bin/vi")))
7114 #:target "mips64el-linux-gnu")
7118 In the example above, the native build of @var{coreutils} is used, so
7119 that @command{ln} can actually run on the host; but then the
7120 cross-compiled build of @var{emacs} is referenced.
7122 @cindex imported modules, for gexps
7123 @findex with-imported-modules
7124 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7125 able to use certain Guile modules from the ``host environment'' in the
7126 gexp, so those modules should be imported in the ``build environment''.
7127 The @code{with-imported-modules} form allows you to express that:
7130 (let ((build (with-imported-modules '((guix build utils))
7132 (use-modules (guix build utils))
7133 (mkdir-p (string-append #$output "/bin"))))))
7134 (gexp->derivation "empty-dir"
7137 (display "success!\n")
7142 In this example, the @code{(guix build utils)} module is automatically
7143 pulled into the isolated build environment of our gexp, such that
7144 @code{(use-modules (guix build utils))} works as expected.
7146 @cindex module closure
7147 @findex source-module-closure
7148 Usually you want the @emph{closure} of the module to be imported---i.e.,
7149 the module itself and all the modules it depends on---rather than just
7150 the module; failing to do that, attempts to use the module will fail
7151 because of missing dependent modules. The @code{source-module-closure}
7152 procedure computes the closure of a module by looking at its source file
7153 headers, which comes in handy in this case:
7156 (use-modules (guix modules)) ;for 'source-module-closure'
7158 (with-imported-modules (source-module-closure
7159 '((guix build utils)
7161 (gexp->derivation "something-with-vms"
7163 (use-modules (guix build utils)
7168 @cindex extensions, for gexps
7169 @findex with-extensions
7170 In the same vein, sometimes you want to import not just pure-Scheme
7171 modules, but also ``extensions'' such as Guile bindings to C libraries
7172 or other ``full-blown'' packages. Say you need the @code{guile-json}
7173 package available on the build side, here's how you would do it:
7176 (use-modules (gnu packages guile)) ;for 'guile-json'
7178 (with-extensions (list guile-json)
7179 (gexp->derivation "something-with-json"
7181 (use-modules (json))
7185 The syntactic form to construct gexps is summarized below.
7187 @deffn {Scheme Syntax} #~@var{exp}
7188 @deffnx {Scheme Syntax} (gexp @var{exp})
7189 Return a G-expression containing @var{exp}. @var{exp} may contain one
7190 or more of the following forms:
7194 @itemx (ungexp @var{obj})
7195 Introduce a reference to @var{obj}. @var{obj} may have one of the
7196 supported types, for example a package or a
7197 derivation, in which case the @code{ungexp} form is replaced by its
7198 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7200 If @var{obj} is a list, it is traversed and references to supported
7201 objects are substituted similarly.
7203 If @var{obj} is another gexp, its contents are inserted and its
7204 dependencies are added to those of the containing gexp.
7206 If @var{obj} is another kind of object, it is inserted as is.
7208 @item #$@var{obj}:@var{output}
7209 @itemx (ungexp @var{obj} @var{output})
7210 This is like the form above, but referring explicitly to the
7211 @var{output} of @var{obj}---this is useful when @var{obj} produces
7212 multiple outputs (@pxref{Packages with Multiple Outputs}).
7215 @itemx #+@var{obj}:output
7216 @itemx (ungexp-native @var{obj})
7217 @itemx (ungexp-native @var{obj} @var{output})
7218 Same as @code{ungexp}, but produces a reference to the @emph{native}
7219 build of @var{obj} when used in a cross compilation context.
7221 @item #$output[:@var{output}]
7222 @itemx (ungexp output [@var{output}])
7223 Insert a reference to derivation output @var{output}, or to the main
7224 output when @var{output} is omitted.
7226 This only makes sense for gexps passed to @code{gexp->derivation}.
7229 @itemx (ungexp-splicing @var{lst})
7230 Like the above, but splices the contents of @var{lst} inside the
7234 @itemx (ungexp-native-splicing @var{lst})
7235 Like the above, but refers to native builds of the objects listed in
7240 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7241 of the @code{gexp?} type (see below.)
7244 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7245 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7246 in their execution environment.
7248 Each item in @var{modules} can be the name of a module, such as
7249 @code{(guix build utils)}, or it can be a module name, followed by an
7250 arrow, followed by a file-like object:
7253 `((guix build utils)
7255 ((guix config) => ,(scheme-file "config.scm"
7256 #~(define-module @dots{}))))
7260 In the example above, the first two modules are taken from the search
7261 path, and the last one is created from the given file-like object.
7263 This form has @emph{lexical} scope: it has an effect on the gexps
7264 directly defined in @var{body}@dots{}, but not on those defined, say, in
7265 procedures called from @var{body}@dots{}.
7268 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7269 Mark the gexps defined in @var{body}@dots{} as requiring
7270 @var{extensions} in their build and execution environment.
7271 @var{extensions} is typically a list of package objects such as those
7272 defined in the @code{(gnu packages guile)} module.
7274 Concretely, the packages listed in @var{extensions} are added to the
7275 load path while compiling imported modules in @var{body}@dots{}; they
7276 are also added to the load path of the gexp returned by
7280 @deffn {Scheme Procedure} gexp? @var{obj}
7281 Return @code{#t} if @var{obj} is a G-expression.
7284 G-expressions are meant to be written to disk, either as code building
7285 some derivation, or as plain files in the store. The monadic procedures
7286 below allow you to do that (@pxref{The Store Monad}, for more
7287 information about monads.)
7289 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7290 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7291 [#:hash #f] [#:hash-algo #f] @
7292 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7293 [#:module-path @var{%load-path}] @
7294 [#:effective-version "2.2"] @
7295 [#:references-graphs #f] [#:allowed-references #f] @
7296 [#:disallowed-references #f] @
7297 [#:leaked-env-vars #f] @
7298 [#:script-name (string-append @var{name} "-builder")] @
7299 [#:deprecation-warnings #f] @
7300 [#:local-build? #f] [#:substitutable? #t] @
7301 [#:properties '()] [#:guile-for-build #f]
7302 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7303 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7304 stored in a file called @var{script-name}. When @var{target} is true,
7305 it is used as the cross-compilation target triplet for packages referred
7308 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7310 make @var{modules} available in the evaluation context of @var{exp};
7311 @var{modules} is a list of names of Guile modules searched in
7312 @var{module-path} to be copied in the store, compiled, and made available in
7313 the load path during the execution of @var{exp}---e.g., @code{((guix
7314 build utils) (guix build gnu-build-system))}.
7316 @var{effective-version} determines the string to use when adding extensions of
7317 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7319 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7322 When @var{references-graphs} is true, it must be a list of tuples of one of the
7326 (@var{file-name} @var{package})
7327 (@var{file-name} @var{package} @var{output})
7328 (@var{file-name} @var{derivation})
7329 (@var{file-name} @var{derivation} @var{output})
7330 (@var{file-name} @var{store-item})
7333 The right-hand-side of each element of @var{references-graphs} is automatically made
7334 an input of the build process of @var{exp}. In the build environment, each
7335 @var{file-name} contains the reference graph of the corresponding item, in a simple
7338 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7339 In the latter case, the list denotes store items that the result is allowed to
7340 refer to. Any reference to another store item will lead to a build error.
7341 Similarly for @var{disallowed-references}, which can list items that must not be
7342 referenced by the outputs.
7344 @var{deprecation-warnings} determines whether to show deprecation warnings while
7345 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7347 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7350 @cindex file-like objects
7351 The @code{local-file}, @code{plain-file}, @code{computed-file},
7352 @code{program-file}, and @code{scheme-file} procedures below return
7353 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7354 these objects lead to a file in the store. Consider this G-expression:
7357 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7358 #$(local-file "/tmp/my-nscd.conf"))
7361 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7362 to the store. Once expanded, for instance @i{via}
7363 @code{gexp->derivation}, the G-expression refers to that copy under
7364 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7365 does not have any effect on what the G-expression does.
7366 @code{plain-file} can be used similarly; it differs in that the file
7367 content is directly passed as a string.
7369 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7370 [#:recursive? #f] [#:select? (const #t)]
7371 Return an object representing local file @var{file} to add to the store; this
7372 object can be used in a gexp. If @var{file} is a relative file name, it is looked
7373 up relative to the source file where this form appears. @var{file} will be added to
7374 the store under @var{name}--by default the base name of @var{file}.
7376 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7377 designates a flat file and @var{recursive?} is true, its contents are added, and its
7378 permission bits are kept.
7380 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7381 @var{stat})} for each directory entry, where @var{file} is the entry's
7382 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7383 entries for which @var{select?} does not return true.
7385 This is the declarative counterpart of the @code{interned-file} monadic
7386 procedure (@pxref{The Store Monad, @code{interned-file}}).
7389 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7390 Return an object representing a text file called @var{name} with the given
7391 @var{content} (a string or a bytevector) to be added to the store.
7393 This is the declarative counterpart of @code{text-file}.
7396 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7397 [#:options '(#:local-build? #t)]
7398 Return an object representing the store item @var{name}, a file or
7399 directory computed by @var{gexp}. @var{options}
7400 is a list of additional arguments to pass to @code{gexp->derivation}.
7402 This is the declarative counterpart of @code{gexp->derivation}.
7405 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7406 [#:guile (default-guile)] [#:module-path %load-path]
7407 Return an executable script @var{name} that runs @var{exp} using
7408 @var{guile}, with @var{exp}'s imported modules in its search path.
7409 Look up @var{exp}'s modules in @var{module-path}.
7411 The example below builds a script that simply invokes the @command{ls}
7415 (use-modules (guix gexp) (gnu packages base))
7417 (gexp->script "list-files"
7418 #~(execl #$(file-append coreutils "/bin/ls")
7422 When ``running'' it through the store (@pxref{The Store Monad,
7423 @code{run-with-store}}), we obtain a derivation that produces an
7424 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7427 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7429 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7433 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7434 [#:guile #f] [#:module-path %load-path]
7435 Return an object representing the executable store item @var{name} that
7436 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7437 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7439 This is the declarative counterpart of @code{gexp->script}.
7442 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7443 [#:set-load-path? #t] [#:module-path %load-path] @
7445 [#:guile (default-guile)]
7446 Return a derivation that builds a file @var{name} containing @var{exp}.
7447 When @var{splice?} is true, @var{exp} is considered to be a list of
7448 expressions that will be spliced in the resulting file.
7450 When @var{set-load-path?} is true, emit code in the resulting file to
7451 set @code{%load-path} and @code{%load-compiled-path} to honor
7452 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7455 The resulting file holds references to all the dependencies of @var{exp}
7456 or a subset thereof.
7459 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7460 Return an object representing the Scheme file @var{name} that contains
7463 This is the declarative counterpart of @code{gexp->file}.
7466 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7467 Return as a monadic value a derivation that builds a text file
7468 containing all of @var{text}. @var{text} may list, in addition to
7469 strings, objects of any type that can be used in a gexp: packages,
7470 derivations, local file objects, etc. The resulting store file holds
7471 references to all these.
7473 This variant should be preferred over @code{text-file} anytime the file
7474 to create will reference items from the store. This is typically the
7475 case when building a configuration file that embeds store file names,
7479 (define (profile.sh)
7480 ;; Return the name of a shell script in the store that
7481 ;; initializes the 'PATH' environment variable.
7482 (text-file* "profile.sh"
7483 "export PATH=" coreutils "/bin:"
7484 grep "/bin:" sed "/bin\n"))
7487 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7488 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7489 preventing them from being garbage-collected during its lifetime.
7492 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7493 Return an object representing store file @var{name} containing
7494 @var{text}. @var{text} is a sequence of strings and file-like objects,
7498 (mixed-text-file "profile"
7499 "export PATH=" coreutils "/bin:" grep "/bin")
7502 This is the declarative counterpart of @code{text-file*}.
7505 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7506 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7507 Each item in @var{files} must be a two-element list where the first element is the
7508 file name to use in the new directory, and the second element is a gexp
7509 denoting the target file. Here's an example:
7513 `(("hosts" ,(plain-file "hosts"
7514 "127.0.0.1 localhost"))
7515 ("bashrc" ,(plain-file "bashrc"
7516 "alias ls='ls --color=auto'"))))
7519 This yields an @code{etc} directory containing these two files.
7522 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
7523 Return a directory that is the union of @var{things}, where @var{things} is a list of
7524 file-like objects denoting directories. For example:
7527 (directory-union "guile+emacs" (list guile emacs))
7530 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
7533 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
7534 Return a file-like object that expands to the concatenation of @var{obj}
7535 and @var{suffix}, where @var{obj} is a lowerable object and each
7536 @var{suffix} is a string.
7538 As an example, consider this gexp:
7541 (gexp->script "run-uname"
7542 #~(system* #$(file-append coreutils
7546 The same effect could be achieved with:
7549 (gexp->script "run-uname"
7550 #~(system* (string-append #$coreutils
7554 There is one difference though: in the @code{file-append} case, the
7555 resulting script contains the absolute file name as a string, whereas in
7556 the second case, the resulting script contains a @code{(string-append
7557 @dots{})} expression to construct the file name @emph{at run time}.
7561 Of course, in addition to gexps embedded in ``host'' code, there are
7562 also modules containing build tools. To make it clear that they are
7563 meant to be used in the build stratum, these modules are kept in the
7564 @code{(guix build @dots{})} name space.
7566 @cindex lowering, of high-level objects in gexps
7567 Internally, high-level objects are @dfn{lowered}, using their compiler,
7568 to either derivations or store items. For instance, lowering a package
7569 yields a derivation, and lowering a @code{plain-file} yields a store
7570 item. This is achieved using the @code{lower-object} monadic procedure.
7572 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
7574 Return as a value in @var{%store-monad} the derivation or store item
7575 corresponding to @var{obj} for @var{system}, cross-compiling for
7576 @var{target} if @var{target} is true. @var{obj} must be an object that
7577 has an associated gexp compiler, such as a @code{<package>}.
7580 @node Invoking guix repl
7581 @section Invoking @command{guix repl}
7583 @cindex REPL, read-eval-print loop
7584 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
7585 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
7586 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
7587 command, @command{guix repl} guarantees that all the Guix modules and all its
7588 dependencies are available in the search path. You can use it this way:
7592 scheme@@(guile-user)> ,use (gnu packages base)
7593 scheme@@(guile-user)> coreutils
7594 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
7598 In addition, @command{guix repl} implements a simple machine-readable REPL
7599 protocol for use by @code{(guix inferior)}, a facility to interact with
7600 @dfn{inferiors}, separate processes running a potentially different revision
7603 The available options are as follows:
7606 @item --type=@var{type}
7607 @itemx -t @var{type}
7608 Start a REPL of the given @var{TYPE}, which can be one of the following:
7612 This is default, and it spawns a standard full-featured Guile REPL.
7614 Spawn a REPL that uses the machine-readable protocol. This is the protocol
7615 that the @code{(guix inferior)} module speaks.
7618 @item --listen=@var{endpoint}
7619 By default, @command{guix repl} reads from standard input and writes to
7620 standard output. When this option is passed, it will instead listen for
7621 connections on @var{endpoint}. Here are examples of valid options:
7624 @item --listen=tcp:37146
7625 Accept connections on localhost on port 37146.
7627 @item --listen=unix:/tmp/socket
7628 Accept connections on the Unix-domain socket @file{/tmp/socket}.
7632 @c *********************************************************************
7636 This section describes Guix command-line utilities. Some of them are
7637 primarily targeted at developers and users who write new package
7638 definitions, while others are more generally useful. They complement
7639 the Scheme programming interface of Guix in a convenient way.
7642 * Invoking guix build:: Building packages from the command line.
7643 * Invoking guix edit:: Editing package definitions.
7644 * Invoking guix download:: Downloading a file and printing its hash.
7645 * Invoking guix hash:: Computing the cryptographic hash of a file.
7646 * Invoking guix import:: Importing package definitions.
7647 * Invoking guix refresh:: Updating package definitions.
7648 * Invoking guix lint:: Finding errors in package definitions.
7649 * Invoking guix size:: Profiling disk usage.
7650 * Invoking guix graph:: Visualizing the graph of packages.
7651 * Invoking guix publish:: Sharing substitutes.
7652 * Invoking guix challenge:: Challenging substitute servers.
7653 * Invoking guix copy:: Copying to and from a remote store.
7654 * Invoking guix container:: Process isolation.
7655 * Invoking guix weather:: Assessing substitute availability.
7656 * Invoking guix processes:: Listing client processes.
7659 @node Invoking guix build
7660 @section Invoking @command{guix build}
7662 @cindex package building
7663 @cindex @command{guix build}
7664 The @command{guix build} command builds packages or derivations and
7665 their dependencies, and prints the resulting store paths. Note that it
7666 does not modify the user's profile---this is the job of the
7667 @command{guix package} command (@pxref{Invoking guix package}). Thus,
7668 it is mainly useful for distribution developers.
7670 The general syntax is:
7673 guix build @var{options} @var{package-or-derivation}@dots{}
7676 As an example, the following command builds the latest versions of Emacs
7677 and of Guile, displays their build logs, and finally displays the
7678 resulting directories:
7681 guix build emacs guile
7684 Similarly, the following command builds all the available packages:
7687 guix build --quiet --keep-going \
7688 `guix package -A | cut -f1,2 --output-delimiter=@@`
7691 @var{package-or-derivation} may be either the name of a package found in
7692 the software distribution such as @code{coreutils} or
7693 @code{coreutils@@8.20}, or a derivation such as
7694 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
7695 package with the corresponding name (and optionally version) is searched
7696 for among the GNU distribution modules (@pxref{Package Modules}).
7698 Alternatively, the @code{--expression} option may be used to specify a
7699 Scheme expression that evaluates to a package; this is useful when
7700 disambiguating among several same-named packages or package variants is
7703 There may be zero or more @var{options}. The available options are
7704 described in the subsections below.
7707 * Common Build Options:: Build options for most commands.
7708 * Package Transformation Options:: Creating variants of packages.
7709 * Additional Build Options:: Options specific to 'guix build'.
7710 * Debugging Build Failures:: Real life packaging experience.
7713 @node Common Build Options
7714 @subsection Common Build Options
7716 A number of options that control the build process are common to
7717 @command{guix build} and other commands that can spawn builds, such as
7718 @command{guix package} or @command{guix archive}. These are the
7723 @item --load-path=@var{directory}
7724 @itemx -L @var{directory}
7725 Add @var{directory} to the front of the package module search path
7726 (@pxref{Package Modules}).
7728 This allows users to define their own packages and make them visible to
7729 the command-line tools.
7733 Keep the build tree of failed builds. Thus, if a build fails, its build
7734 tree is kept under @file{/tmp}, in a directory whose name is shown at
7735 the end of the build log. This is useful when debugging build issues.
7736 @xref{Debugging Build Failures}, for tips and tricks on how to debug
7739 This option has no effect when connecting to a remote daemon with a
7740 @code{guix://} URI (@pxref{The Store, the @code{GUIX_DAEMON_SOCKET}
7745 Keep going when some of the derivations fail to build; return only once
7746 all the builds have either completed or failed.
7748 The default behavior is to stop as soon as one of the specified
7749 derivations has failed.
7753 Do not build the derivations.
7755 @anchor{fallback-option}
7757 When substituting a pre-built binary fails, fall back to building
7758 packages locally (@pxref{Substitution Failure}).
7760 @item --substitute-urls=@var{urls}
7761 @anchor{client-substitute-urls}
7762 Consider @var{urls} the whitespace-separated list of substitute source
7763 URLs, overriding the default list of URLs of @command{guix-daemon}
7764 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
7766 This means that substitutes may be downloaded from @var{urls}, provided
7767 they are signed by a key authorized by the system administrator
7768 (@pxref{Substitutes}).
7770 When @var{urls} is the empty string, substitutes are effectively
7773 @item --no-substitutes
7774 Do not use substitutes for build products. That is, always build things
7775 locally instead of allowing downloads of pre-built binaries
7776 (@pxref{Substitutes}).
7779 Do not ``graft'' packages. In practice, this means that package updates
7780 available as grafts are not applied. @xref{Security Updates}, for more
7781 information on grafts.
7783 @item --rounds=@var{n}
7784 Build each derivation @var{n} times in a row, and raise an error if
7785 consecutive build results are not bit-for-bit identical.
7787 This is a useful way to detect non-deterministic builds processes.
7788 Non-deterministic build processes are a problem because they make it
7789 practically impossible for users to @emph{verify} whether third-party
7790 binaries are genuine. @xref{Invoking guix challenge}, for more.
7792 Note that, currently, the differing build results are not kept around,
7793 so you will have to manually investigate in case of an error---e.g., by
7794 stashing one of the build results with @code{guix archive --export}
7795 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
7798 @item --no-build-hook
7799 Do not attempt to offload builds @i{via} the ``build hook'' of the daemon
7800 (@pxref{Daemon Offload Setup}). That is, always build things locally
7801 instead of offloading builds to remote machines.
7803 @item --max-silent-time=@var{seconds}
7804 When the build or substitution process remains silent for more than
7805 @var{seconds}, terminate it and report a build failure.
7807 By default, the daemon's setting is honored (@pxref{Invoking
7808 guix-daemon, @code{--max-silent-time}}).
7810 @item --timeout=@var{seconds}
7811 Likewise, when the build or substitution process lasts for more than
7812 @var{seconds}, terminate it and report a build failure.
7814 By default, the daemon's setting is honored (@pxref{Invoking
7815 guix-daemon, @code{--timeout}}).
7817 @c Note: This option is actually not part of %standard-build-options but
7818 @c most programs honor it.
7819 @cindex verbosity, of the command-line tools
7820 @cindex build logs, verbosity
7821 @item -v @var{level}
7822 @itemx --verbosity=@var{level}
7823 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
7824 output is produced, 1 is for quiet output, and 2 shows all the build log
7825 output on standard error.
7827 @item --cores=@var{n}
7829 Allow the use of up to @var{n} CPU cores for the build. The special
7830 value @code{0} means to use as many CPU cores as available.
7832 @item --max-jobs=@var{n}
7834 Allow at most @var{n} build jobs in parallel. @xref{Invoking
7835 guix-daemon, @code{--max-jobs}}, for details about this option and the
7836 equivalent @command{guix-daemon} option.
7838 @item --debug=@var{level}
7839 Produce debugging output coming from the build daemon. @var{level} must be an
7840 integer between 0 and 5; higher means more verbose output. Setting a level of
7841 4 or more may be helpful when debugging setup issues with the build daemon.
7845 Behind the scenes, @command{guix build} is essentially an interface to
7846 the @code{package-derivation} procedure of the @code{(guix packages)}
7847 module, and to the @code{build-derivations} procedure of the @code{(guix
7848 derivations)} module.
7850 In addition to options explicitly passed on the command line,
7851 @command{guix build} and other @command{guix} commands that support
7852 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
7854 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
7855 Users can define this variable to a list of command line options that
7856 will automatically be used by @command{guix build} and other
7857 @command{guix} commands that can perform builds, as in the example
7861 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
7864 These options are parsed independently, and the result is appended to
7865 the parsed command-line options.
7869 @node Package Transformation Options
7870 @subsection Package Transformation Options
7872 @cindex package variants
7873 Another set of command-line options supported by @command{guix build}
7874 and also @command{guix package} are @dfn{package transformation
7875 options}. These are options that make it possible to define @dfn{package
7876 variants}---for instance, packages built from different source code.
7877 This is a convenient way to create customized packages on the fly
7878 without having to type in the definitions of package variants
7879 (@pxref{Defining Packages}).
7883 @item --with-source=@var{source}
7884 @itemx --with-source=@var{package}=@var{source}
7885 @itemx --with-source=@var{package}@@@var{version}=@var{source}
7886 Use @var{source} as the source of @var{package}, and @var{version} as
7888 @var{source} must be a file name or a URL, as for @command{guix
7889 download} (@pxref{Invoking guix download}).
7891 When @var{package} is omitted,
7892 it is taken to be the package name specified on the
7893 command line that matches the base of @var{source}---e.g.,
7894 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
7895 package is @code{guile}.
7897 Likewise, when @var{version} is omitted, the version string is inferred from
7898 @var{source}; in the previous example, it is @code{2.0.10}.
7900 This option allows users to try out versions of packages other than the
7901 one provided by the distribution. The example below downloads
7902 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
7903 the @code{ed} package:
7906 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
7909 As a developer, @code{--with-source} makes it easy to test release
7913 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
7916 @dots{} or to build from a checkout in a pristine environment:
7919 $ git clone git://git.sv.gnu.org/guix.git
7920 $ guix build guix --with-source=guix@@1.0=./guix
7923 @item --with-input=@var{package}=@var{replacement}
7924 Replace dependency on @var{package} by a dependency on
7925 @var{replacement}. @var{package} must be a package name, and
7926 @var{replacement} must be a package specification such as @code{guile}
7927 or @code{guile@@1.8}.
7929 For instance, the following command builds Guix, but replaces its
7930 dependency on the current stable version of Guile with a dependency on
7931 the legacy version of Guile, @code{guile@@2.0}:
7934 guix build --with-input=guile=guile@@2.0 guix
7937 This is a recursive, deep replacement. So in this example, both
7938 @code{guix} and its dependency @code{guile-json} (which also depends on
7939 @code{guile}) get rebuilt against @code{guile@@2.0}.
7941 This is implemented using the @code{package-input-rewriting} Scheme
7942 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
7944 @item --with-graft=@var{package}=@var{replacement}
7945 This is similar to @code{--with-input} but with an important difference:
7946 instead of rebuilding the whole dependency chain, @var{replacement} is
7947 built and then @dfn{grafted} onto the binaries that were initially
7948 referring to @var{package}. @xref{Security Updates}, for more
7949 information on grafts.
7951 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
7952 and all its dependencies, replacing references to the version of GnuTLS
7953 they currently refer to:
7956 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
7959 This has the advantage of being much faster than rebuilding everything.
7960 But there is a caveat: it works if and only if @var{package} and
7961 @var{replacement} are strictly compatible---for example, if they provide
7962 a library, the application binary interface (ABI) of those libraries
7963 must be compatible. If @var{replacement} is somehow incompatible with
7964 @var{package}, then the resulting package may be unusable. Use with
7967 @item --with-git-url=@var{package}=@var{url}
7968 @cindex Git, using the latest commit
7969 @cindex latest commit, building
7970 Build @var{package} from the latest commit of the @code{master} branch of the
7971 Git repository at @var{url}. Git sub-modules of the repository are fetched,
7974 For example, the following command builds the NumPy Python library against the
7975 latest commit of the master branch of Python itself:
7978 guix build python-numpy \
7979 --with-git-url=python=https://github.com/python/cpython
7982 This option can also be combined with @code{--with-branch} or
7983 @code{--with-commit} (see below).
7985 @cindex continuous integration
7986 Obviously, since it uses the latest commit of the given branch, the result of
7987 such a command varies over time. Nevertheless it is a convenient way to
7988 rebuild entire software stacks against the latest commit of one or more
7989 packages. This is particularly useful in the context of continuous
7992 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
7993 consecutive accesses to the same repository. You may want to clean it up once
7994 in a while to save disk space.
7996 @item --with-branch=@var{package}=@var{branch}
7997 Build @var{package} from the latest commit of @var{branch}. If the
7998 @code{source} field of @var{package} is an origin with the @code{git-fetch}
7999 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8000 repository URL is taken from that @code{source}. Otherwise you have to use
8001 @code{--with-git-url} to specify the URL of the Git repository.
8003 For instance, the following command builds @code{guile-sqlite3} from the
8004 latest commit of its @code{master} branch, and then builds @code{guix} (which
8005 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8006 specific @code{guile-sqlite3} build:
8009 guix build --with-branch=guile-sqlite3=master cuirass
8012 @item --with-commit=@var{package}=@var{commit}
8013 This is similar to @code{--with-branch}, except that it builds from
8014 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8015 Git commit SHA1 identifier.
8018 @node Additional Build Options
8019 @subsection Additional Build Options
8021 The command-line options presented below are specific to @command{guix
8028 Build quietly, without displaying the build log; this is equivalent to
8029 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8030 (or similar) and can always be retrieved using the @option{--log-file} option.
8032 @item --file=@var{file}
8033 @itemx -f @var{file}
8034 Build the package, derivation, or other file-like object that the code within
8035 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8037 As an example, @var{file} might contain a package definition like this
8038 (@pxref{Defining Packages}):
8041 @verbatiminclude package-hello.scm
8044 @item --expression=@var{expr}
8045 @itemx -e @var{expr}
8046 Build the package or derivation @var{expr} evaluates to.
8048 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8049 guile-1.8)}, which unambiguously designates this specific variant of
8050 version 1.8 of Guile.
8052 Alternatively, @var{expr} may be a G-expression, in which case it is used
8053 as a build program passed to @code{gexp->derivation}
8054 (@pxref{G-Expressions}).
8056 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8057 (@pxref{The Store Monad}). The procedure must return a derivation as a
8058 monadic value, which is then passed through @code{run-with-store}.
8062 Build the source derivations of the packages, rather than the packages
8065 For instance, @code{guix build -S gcc} returns something like
8066 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8069 The returned source tarball is the result of applying any patches and
8070 code snippets specified in the package @code{origin} (@pxref{Defining
8074 Fetch and return the source of @var{package-or-derivation} and all their
8075 dependencies, recursively. This is a handy way to obtain a local copy
8076 of all the source code needed to build @var{packages}, allowing you to
8077 eventually build them even without network access. It is an extension
8078 of the @code{--source} option and can accept one of the following
8079 optional argument values:
8083 This value causes the @code{--sources} option to behave in the same way
8084 as the @code{--source} option.
8087 Build the source derivations of all packages, including any source that
8088 might be listed as @code{inputs}. This is the default value.
8091 $ guix build --sources tzdata
8092 The following derivations will be built:
8093 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8094 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8098 Build the source derivations of all packages, as well of all transitive
8099 inputs to the packages. This can be used e.g.@: to
8100 prefetch package source for later offline building.
8103 $ guix build --sources=transitive tzdata
8104 The following derivations will be built:
8105 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8106 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8107 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8108 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8109 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8110 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8116 @item --system=@var{system}
8117 @itemx -s @var{system}
8118 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8119 the system type of the build host. The @command{guix build} command allows
8120 you to repeat this option several times, in which case it builds for all the
8121 specified systems; other commands ignore extraneous @option{-s} options.
8124 The @code{--system} flag is for @emph{native} compilation and must not
8125 be confused with cross-compilation. See @code{--target} below for
8126 information on cross-compilation.
8129 An example use of this is on Linux-based systems, which can emulate
8130 different personalities. For instance, passing
8131 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8132 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8133 to build packages in a complete 32-bit environment.
8136 Building for an @code{armhf-linux} system is unconditionally enabled on
8137 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8138 allow for this functionality, notably the ThunderX.
8141 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8142 is enabled (@pxref{Virtualization Services,
8143 @code{qemu-binfmt-service-type}}), you can build for any system for
8144 which a QEMU @code{binfmt_misc} handler is installed.
8146 Builds for a system other than that of the machine you are using can
8147 also be offloaded to a remote machine of the right architecture.
8148 @xref{Daemon Offload Setup}, for more information on offloading.
8150 @item --target=@var{triplet}
8151 @cindex cross-compilation
8152 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8153 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8154 configuration triplets,, autoconf, Autoconf}).
8156 @anchor{build-check}
8158 @cindex determinism, checking
8159 @cindex reproducibility, checking
8160 Rebuild @var{package-or-derivation}, which are already available in the
8161 store, and raise an error if the build results are not bit-for-bit
8164 This mechanism allows you to check whether previously installed
8165 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8166 of a package is deterministic. @xref{Invoking guix challenge}, for more
8167 background information and tools.
8169 When used in conjunction with @option{--keep-failed}, the differing
8170 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8171 This makes it easy to look for differences between the two results.
8174 @cindex repairing store items
8175 @cindex corruption, recovering from
8176 Attempt to repair the specified store items, if they are corrupt, by
8177 re-downloading or rebuilding them.
8179 This operation is not atomic and thus restricted to @code{root}.
8183 Return the derivation paths, not the output paths, of the given
8186 @item --root=@var{file}
8187 @itemx -r @var{file}
8188 @cindex GC roots, adding
8189 @cindex garbage collector roots, adding
8190 Make @var{file} a symlink to the result, and register it as a garbage
8193 Consequently, the results of this @command{guix build} invocation are
8194 protected from garbage collection until @var{file} is removed. When
8195 that option is omitted, build results are eligible for garbage
8196 collection as soon as the build completes. @xref{Invoking guix gc}, for
8200 @cindex build logs, access
8201 Return the build log file names or URLs for the given
8202 @var{package-or-derivation}, or raise an error if build logs are
8205 This works regardless of how packages or derivations are specified. For
8206 instance, the following invocations are equivalent:
8209 guix build --log-file `guix build -d guile`
8210 guix build --log-file `guix build guile`
8211 guix build --log-file guile
8212 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8215 If a log is unavailable locally, and unless @code{--no-substitutes} is
8216 passed, the command looks for a corresponding log on one of the
8217 substitute servers (as specified with @code{--substitute-urls}.)
8219 So for instance, imagine you want to see the build log of GDB on MIPS,
8220 but you are actually on an @code{x86_64} machine:
8223 $ guix build --log-file gdb -s mips64el-linux
8224 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8227 You can freely access a huge library of build logs!
8230 @node Debugging Build Failures
8231 @subsection Debugging Build Failures
8233 @cindex build failures, debugging
8234 When defining a new package (@pxref{Defining Packages}), you will
8235 probably find yourself spending some time debugging and tweaking the
8236 build until it succeeds. To do that, you need to operate the build
8237 commands yourself in an environment as close as possible to the one the
8240 To that end, the first thing to do is to use the @option{--keep-failed}
8241 or @option{-K} option of @command{guix build}, which will keep the
8242 failed build tree in @file{/tmp} or whatever directory you specified as
8243 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8245 From there on, you can @command{cd} to the failed build tree and source
8246 the @file{environment-variables} file, which contains all the
8247 environment variable definitions that were in place when the build
8248 failed. So let's say you're debugging a build failure in package
8249 @code{foo}; a typical session would look like this:
8253 @dots{} @i{build fails}
8254 $ cd /tmp/guix-build-foo.drv-0
8255 $ source ./environment-variables
8259 Now, you can invoke commands as if you were the daemon (almost) and
8260 troubleshoot your build process.
8262 Sometimes it happens that, for example, a package's tests pass when you
8263 run them manually but they fail when the daemon runs them. This can
8264 happen because the daemon runs builds in containers where, unlike in our
8265 environment above, network access is missing, @file{/bin/sh} does not
8266 exist, etc. (@pxref{Build Environment Setup}).
8268 In such cases, you may need to run inspect the build process from within
8269 a container similar to the one the build daemon creates:
8274 $ cd /tmp/guix-build-foo.drv-0
8275 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8276 [env]# source ./environment-variables
8280 Here, @command{guix environment -C} creates a container and spawns a new
8281 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8282 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8283 the container, which would may find handy while debugging. The
8284 @option{--no-grafts} option makes sure we get the exact same
8285 environment, with ungrafted packages (@pxref{Security Updates}, for more
8288 To get closer to a container like that used by the build daemon, we can
8289 remove @file{/bin/sh}:
8295 (Don't worry, this is harmless: this is all happening in the throw-away
8296 container created by @command{guix environment}.)
8298 The @command{strace} command is probably not in the search path, but we
8302 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8305 In this way, not only you will have reproduced the environment variables
8306 the daemon uses, you will also be running the build process in a container
8307 similar to the one the daemon uses.
8310 @node Invoking guix edit
8311 @section Invoking @command{guix edit}
8313 @cindex @command{guix edit}
8314 @cindex package definition, editing
8315 So many packages, so many source files! The @command{guix edit} command
8316 facilitates the life of users and packagers by pointing their editor at
8317 the source file containing the definition of the specified packages.
8321 guix edit gcc@@4.9 vim
8325 launches the program specified in the @code{VISUAL} or in the
8326 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8329 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8330 have created your own packages on @code{GUIX_PACKAGE_PATH}
8331 (@pxref{Package Modules}), you will be able to edit the package
8332 recipes. In other cases, you will be able to examine the read-only recipes
8333 for packages currently in the store.
8336 @node Invoking guix download
8337 @section Invoking @command{guix download}
8339 @cindex @command{guix download}
8340 @cindex downloading package sources
8341 When writing a package definition, developers typically need to download
8342 a source tarball, compute its SHA256 hash, and write that
8343 hash in the package definition (@pxref{Defining Packages}). The
8344 @command{guix download} tool helps with this task: it downloads a file
8345 from the given URI, adds it to the store, and prints both its file name
8346 in the store and its SHA256 hash.
8348 The fact that the downloaded file is added to the store saves bandwidth:
8349 when the developer eventually tries to build the newly defined package
8350 with @command{guix build}, the source tarball will not have to be
8351 downloaded again because it is already in the store. It is also a
8352 convenient way to temporarily stash files, which may be deleted
8353 eventually (@pxref{Invoking guix gc}).
8355 The @command{guix download} command supports the same URIs as used in
8356 package definitions. In particular, it supports @code{mirror://} URIs.
8357 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8358 Guile bindings for GnuTLS are available in the user's environment; when
8359 they are not available, an error is raised. @xref{Guile Preparations,
8360 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8361 GnuTLS-Guile}, for more information.
8363 @command{guix download} verifies HTTPS server certificates by loading
8364 the certificates of X.509 authorities from the directory pointed to by
8365 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8366 Certificates}), unless @option{--no-check-certificate} is used.
8368 The following options are available:
8371 @item --format=@var{fmt}
8373 Write the hash in the format specified by @var{fmt}. For more
8374 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8376 @item --no-check-certificate
8377 Do not validate the X.509 certificates of HTTPS servers.
8379 When using this option, you have @emph{absolutely no guarantee} that you
8380 are communicating with the authentic server responsible for the given
8381 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8383 @item --output=@var{file}
8384 @itemx -o @var{file}
8385 Save the downloaded file to @var{file} instead of adding it to the
8389 @node Invoking guix hash
8390 @section Invoking @command{guix hash}
8392 @cindex @command{guix hash}
8393 The @command{guix hash} command computes the SHA256 hash of a file.
8394 It is primarily a convenience tool for anyone contributing to the
8395 distribution: it computes the cryptographic hash of a file, which can be
8396 used in the definition of a package (@pxref{Defining Packages}).
8398 The general syntax is:
8401 guix hash @var{option} @var{file}
8404 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8405 hash of data read from standard input. @command{guix hash} has the
8410 @item --format=@var{fmt}
8412 Write the hash in the format specified by @var{fmt}.
8414 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8415 (@code{hex} and @code{hexadecimal} can be used as well).
8417 If the @option{--format} option is not specified, @command{guix hash}
8418 will output the hash in @code{nix-base32}. This representation is used
8419 in the definitions of packages.
8423 Compute the hash on @var{file} recursively.
8425 In this case, the hash is computed on an archive containing @var{file},
8426 including its children if it is a directory. Some of the metadata of
8427 @var{file} is part of the archive; for instance, when @var{file} is a
8428 regular file, the hash is different depending on whether @var{file} is
8429 executable or not. Metadata such as time stamps has no impact on the
8430 hash (@pxref{Invoking guix archive}).
8431 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8436 When combined with @option{--recursive}, exclude version control system
8437 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8440 As an example, here is how you would compute the hash of a Git checkout,
8441 which is useful when using the @code{git-fetch} method (@pxref{origin
8445 $ git clone http://example.org/foo.git
8451 @node Invoking guix import
8452 @section Invoking @command{guix import}
8454 @cindex importing packages
8455 @cindex package import
8456 @cindex package conversion
8457 @cindex Invoking @command{guix import}
8458 The @command{guix import} command is useful for people who would like to
8459 add a package to the distribution with as little work as
8460 possible---a legitimate demand. The command knows of a few
8461 repositories from which it can ``import'' package metadata. The result
8462 is a package definition, or a template thereof, in the format we know
8463 (@pxref{Defining Packages}).
8465 The general syntax is:
8468 guix import @var{importer} @var{options}@dots{}
8471 @var{importer} specifies the source from which to import package
8472 metadata, and @var{options} specifies a package identifier and other
8473 options specific to @var{importer}. Currently, the available
8478 Import metadata for the given GNU package. This provides a template
8479 for the latest version of that GNU package, including the hash of its
8480 source tarball, and its canonical synopsis and description.
8482 Additional information such as the package dependencies and its
8483 license needs to be figured out manually.
8485 For example, the following command returns a package definition for
8489 guix import gnu hello
8492 Specific command-line options are:
8495 @item --key-download=@var{policy}
8496 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
8497 keys when verifying the package signature. @xref{Invoking guix
8498 refresh, @code{--key-download}}.
8503 Import metadata from the @uref{https://pypi.python.org/, Python Package
8504 Index}. Information is taken from the JSON-formatted description
8505 available at @code{pypi.python.org} and usually includes all the relevant
8506 information, including package dependencies. For maximum efficiency, it
8507 is recommended to install the @command{unzip} utility, so that the
8508 importer can unzip Python wheels and gather data from them.
8510 The command below imports metadata for the @code{itsdangerous} Python
8514 guix import pypi itsdangerous
8520 Traverse the dependency graph of the given upstream package recursively
8521 and generate package expressions for all those packages that are not yet
8527 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
8528 is taken from the JSON-formatted description available at
8529 @code{rubygems.org} and includes most relevant information, including
8530 runtime dependencies. There are some caveats, however. The metadata
8531 doesn't distinguish between synopses and descriptions, so the same string
8532 is used for both fields. Additionally, the details of non-Ruby
8533 dependencies required to build native extensions is unavailable and left
8534 as an exercise to the packager.
8536 The command below imports metadata for the @code{rails} Ruby package:
8539 guix import gem rails
8545 Traverse the dependency graph of the given upstream package recursively
8546 and generate package expressions for all those packages that are not yet
8552 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
8553 Information is taken from the JSON-formatted metadata provided through
8554 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
8555 relevant information, such as module dependencies. License information
8556 should be checked closely. If Perl is available in the store, then the
8557 @code{corelist} utility will be used to filter core modules out of the
8558 list of dependencies.
8560 The command command below imports metadata for the @code{Acme::Boolean}
8564 guix import cpan Acme::Boolean
8569 @cindex Bioconductor
8570 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
8571 central repository for the @uref{https://r-project.org, GNU@tie{}R
8572 statistical and graphical environment}.
8574 Information is extracted from the @code{DESCRIPTION} file of the package.
8576 The command command below imports metadata for the @code{Cairo}
8580 guix import cran Cairo
8583 When @code{--recursive} is added, the importer will traverse the
8584 dependency graph of the given upstream package recursively and generate
8585 package expressions for all those packages that are not yet in Guix.
8587 When @code{--archive=bioconductor} is added, metadata is imported from
8588 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
8589 packages for for the analysis and comprehension of high-throughput
8590 genomic data in bioinformatics.
8592 Information is extracted from the @code{DESCRIPTION} file of a package
8593 published on the web interface of the Bioconductor SVN repository.
8595 The command below imports metadata for the @code{GenomicRanges}
8599 guix import cran --archive=bioconductor GenomicRanges
8605 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
8606 comprehensive TeX archive network for TeX packages that are part of the
8607 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
8609 Information about the package is obtained through the XML API provided
8610 by CTAN, while the source code is downloaded from the SVN repository of
8611 the Tex Live project. This is done because the CTAN does not keep
8614 The command command below imports metadata for the @code{fontspec}
8618 guix import texlive fontspec
8621 When @code{--archive=DIRECTORY} is added, the source code is downloaded
8622 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
8623 tree in the TeX Live SVN repository, but from the specified sibling
8624 directory under the same root.
8626 The command below imports metadata for the @code{ifxetex} package from
8627 CTAN while fetching the sources from the directory
8628 @file{texmf/source/generic}:
8631 guix import texlive --archive=generic ifxetex
8635 @cindex JSON, import
8636 Import package metadata from a local JSON file. Consider the following
8637 example package definition in JSON format:
8643 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
8644 "build-system": "gnu",
8645 "home-page": "https://www.gnu.org/software/hello/",
8646 "synopsis": "Hello, GNU world: An example GNU package",
8647 "description": "GNU Hello prints a greeting.",
8648 "license": "GPL-3.0+",
8649 "native-inputs": ["gcc@@6"]
8653 The field names are the same as for the @code{<package>} record
8654 (@xref{Defining Packages}). References to other packages are provided
8655 as JSON lists of quoted package specification strings such as
8656 @code{guile} or @code{guile@@2.0}.
8658 The importer also supports a more explicit source definition using the
8659 common fields for @code{<origin>} records:
8665 "method": "url-fetch",
8666 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
8668 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
8675 The command below reads metadata from the JSON file @code{hello.json}
8676 and outputs a package expression:
8679 guix import json hello.json
8683 Import metadata from a local copy of the source of the
8684 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
8685 relies on the @command{nix-instantiate} command of
8686 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
8687 typically written in a mixture of Nix-language and Bash code. This
8688 command only imports the high-level package structure that is written in
8689 the Nix language. It normally includes all the basic fields of a
8692 When importing a GNU package, the synopsis and descriptions are replaced
8693 by their canonical upstream variant.
8695 Usually, you will first need to do:
8698 export NIX_REMOTE=daemon
8702 so that @command{nix-instantiate} does not try to open the Nix database.
8704 As an example, the command below imports the package definition of
8705 LibreOffice (more precisely, it imports the definition of the package
8706 bound to the @code{libreoffice} top-level attribute):
8709 guix import nix ~/path/to/nixpkgs libreoffice
8714 Import metadata from the Haskell community's central package archive
8715 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
8716 Cabal files and includes all the relevant information, including package
8719 Specific command-line options are:
8724 Read a Cabal file from standard input.
8725 @item --no-test-dependencies
8727 Do not include dependencies required only by the test suites.
8728 @item --cabal-environment=@var{alist}
8729 @itemx -e @var{alist}
8730 @var{alist} is a Scheme alist defining the environment in which the
8731 Cabal conditionals are evaluated. The accepted keys are: @code{os},
8732 @code{arch}, @code{impl} and a string representing the name of a flag.
8733 The value associated with a flag has to be either the symbol
8734 @code{true} or @code{false}. The value associated with other keys
8735 has to conform to the Cabal file format definition. The default value
8736 associated with the keys @code{os}, @code{arch} and @code{impl} is
8737 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
8740 Traverse the dependency graph of the given upstream package recursively
8741 and generate package expressions for all those packages that are not yet
8745 The command below imports metadata for the latest version of the
8746 @code{HTTP} Haskell package without including test dependencies and
8747 specifying the value of the flag @samp{network-uri} as @code{false}:
8750 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
8753 A specific package version may optionally be specified by following the
8754 package name by an at-sign and a version number as in the following example:
8757 guix import hackage mtl@@2.1.3.1
8762 The @code{stackage} importer is a wrapper around the @code{hackage} one.
8763 It takes a package name, looks up the package version included in a
8764 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
8765 release and uses the @code{hackage} importer to retrieve its metadata.
8766 Note that it is up to you to select an LTS release compatible with the
8767 GHC compiler used by Guix.
8769 Specific command-line options are:
8772 @item --no-test-dependencies
8774 Do not include dependencies required only by the test suites.
8775 @item --lts-version=@var{version}
8776 @itemx -l @var{version}
8777 @var{version} is the desired LTS release version. If omitted the latest
8781 Traverse the dependency graph of the given upstream package recursively
8782 and generate package expressions for all those packages that are not yet
8786 The command below imports metadata for the @code{HTTP} Haskell package
8787 included in the LTS Stackage release version 7.18:
8790 guix import stackage --lts-version=7.18 HTTP
8795 Import metadata from an Emacs Lisp Package Archive (ELPA) package
8796 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
8798 Specific command-line options are:
8801 @item --archive=@var{repo}
8802 @itemx -a @var{repo}
8803 @var{repo} identifies the archive repository from which to retrieve the
8804 information. Currently the supported repositories and their identifiers
8808 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
8809 identifier. This is the default.
8811 Packages from @code{elpa.gnu.org} are signed with one of the keys
8812 contained in the GnuPG keyring at
8813 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
8814 @code{emacs} package (@pxref{Package Installation, ELPA package
8815 signatures,, emacs, The GNU Emacs Manual}).
8818 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
8819 @code{melpa-stable} identifier.
8822 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
8828 Traverse the dependency graph of the given upstream package recursively
8829 and generate package expressions for all those packages that are not yet
8835 Import metadata from the crates.io Rust package repository
8836 @uref{https://crates.io, crates.io}.
8841 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
8842 repository used by the OCaml community.
8845 The structure of the @command{guix import} code is modular. It would be
8846 useful to have more importers for other package formats, and your help
8847 is welcome here (@pxref{Contributing}).
8849 @node Invoking guix refresh
8850 @section Invoking @command{guix refresh}
8852 @cindex @command {guix refresh}
8853 The primary audience of the @command{guix refresh} command is developers
8854 of the GNU software distribution. By default, it reports any packages
8855 provided by the distribution that are outdated compared to the latest
8856 upstream version, like this:
8860 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
8861 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
8864 Alternately, one can specify packages to consider, in which case a
8865 warning is emitted for packages that lack an updater:
8868 $ guix refresh coreutils guile guile-ssh
8869 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
8870 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
8873 @command{guix refresh} browses the upstream repository of each package and determines
8874 the highest version number of the releases therein. The command
8875 knows how to update specific types of packages: GNU packages, ELPA
8876 packages, etc.---see the documentation for @option{--type} below. There
8877 are many packages, though, for which it lacks a method to determine
8878 whether a new upstream release is available. However, the mechanism is
8879 extensible, so feel free to get in touch with us to add a new method!
8884 Consider the packages specified, and all the packages upon which they depend.
8887 $ guix refresh --recursive coreutils
8888 gnu/packages/acl.scm:35:2: warning: no updater for acl
8889 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
8890 gnu/packages/xml.scm:68:2: warning: no updater for expat
8891 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
8897 Sometimes the upstream name differs from the package name used in Guix,
8898 and @command{guix refresh} needs a little help. Most updaters honor the
8899 @code{upstream-name} property in package definitions, which can be used
8903 (define-public network-manager
8905 (name "network-manager")
8907 (properties '((upstream-name . "NetworkManager")))))
8910 When passed @code{--update}, it modifies distribution source files to
8911 update the version numbers and source tarball hashes of those package
8912 recipes (@pxref{Defining Packages}). This is achieved by downloading
8913 each package's latest source tarball and its associated OpenPGP
8914 signature, authenticating the downloaded tarball against its signature
8915 using @command{gpg}, and finally computing its hash. When the public
8916 key used to sign the tarball is missing from the user's keyring, an
8917 attempt is made to automatically retrieve it from a public key server;
8918 when this is successful, the key is added to the user's keyring; otherwise,
8919 @command{guix refresh} reports an error.
8921 The following options are supported:
8925 @item --expression=@var{expr}
8926 @itemx -e @var{expr}
8927 Consider the package @var{expr} evaluates to.
8929 This is useful to precisely refer to a package, as in this example:
8932 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
8935 This command lists the dependents of the ``final'' libc (essentially all
8940 Update distribution source files (package recipes) in place. This is
8941 usually run from a checkout of the Guix source tree (@pxref{Running
8942 Guix Before It Is Installed}):
8945 $ ./pre-inst-env guix refresh -s non-core -u
8948 @xref{Defining Packages}, for more information on package definitions.
8950 @item --select=[@var{subset}]
8951 @itemx -s @var{subset}
8952 Select all the packages in @var{subset}, one of @code{core} or
8955 The @code{core} subset refers to all the packages at the core of the
8956 distribution---i.e., packages that are used to build ``everything
8957 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
8958 changing one of these packages in the distribution entails a rebuild of
8959 all the others. Thus, such updates are an inconvenience to users in
8960 terms of build time or bandwidth used to achieve the upgrade.
8962 The @code{non-core} subset refers to the remaining packages. It is
8963 typically useful in cases where an update of the core packages would be
8966 @item --manifest=@var{file}
8967 @itemx -m @var{file}
8968 Select all the packages from the manifest in @var{file}. This is useful to
8969 check if any packages of the user manifest can be updated.
8971 @item --type=@var{updater}
8972 @itemx -t @var{updater}
8973 Select only packages handled by @var{updater} (may be a comma-separated
8974 list of updaters). Currently, @var{updater} may be one of:
8978 the updater for GNU packages;
8980 the updater for GNOME packages;
8982 the updater for KDE packages;
8984 the updater for X.org packages;
8986 the updater for packages hosted on kernel.org;
8988 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
8990 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
8992 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
8994 the updater for @uref{https://www.cpan.org/, CPAN} packages;
8996 the updater for @uref{https://pypi.python.org, PyPI} packages.
8998 the updater for @uref{https://rubygems.org, RubyGems} packages.
9000 the updater for @uref{https://github.com, GitHub} packages.
9002 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9004 the updater for @uref{https://www.stackage.org, Stackage} packages.
9006 the updater for @uref{https://crates.io, Crates} packages.
9008 the updater for @uref{https://launchpad.net, Launchpad} packages.
9011 For instance, the following command only checks for updates of Emacs
9012 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9015 $ guix refresh --type=elpa,cran
9016 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9017 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9022 In addition, @command{guix refresh} can be passed one or more package
9023 names, as in this example:
9026 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9030 The command above specifically updates the @code{emacs} and
9031 @code{idutils} packages. The @code{--select} option would have no
9032 effect in this case.
9034 When considering whether to upgrade a package, it is sometimes
9035 convenient to know which packages would be affected by the upgrade and
9036 should be checked for compatibility. For this the following option may
9037 be used when passing @command{guix refresh} one or more package names:
9041 @item --list-updaters
9043 List available updaters and exit (see @option{--type} above.)
9045 For each updater, display the fraction of packages it covers; at the
9046 end, display the fraction of packages covered by all these updaters.
9048 @item --list-dependent
9050 List top-level dependent packages that would need to be rebuilt as a
9051 result of upgrading one or more packages.
9053 @xref{Invoking guix graph, the @code{reverse-package} type of
9054 @command{guix graph}}, for information on how to visualize the list of
9055 dependents of a package.
9059 Be aware that the @code{--list-dependent} option only
9060 @emph{approximates} the rebuilds that would be required as a result of
9061 an upgrade. More rebuilds might be required under some circumstances.
9064 $ guix refresh --list-dependent flex
9065 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9066 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9069 The command above lists a set of packages that could be built to check
9070 for compatibility with an upgraded @code{flex} package.
9074 @item --list-transitive
9075 List all the packages which one or more packages depend upon.
9078 $ guix refresh --list-transitive flex
9079 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9080 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{}
9085 The command above lists a set of packages which, when changed, would cause
9086 @code{flex} to be rebuilt.
9088 The following options can be used to customize GnuPG operation:
9092 @item --gpg=@var{command}
9093 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9094 for in @code{$PATH}.
9096 @item --keyring=@var{file}
9097 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9098 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9099 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9100 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9101 information on a tool to manipulate keybox files).
9103 When this option is omitted, @command{guix refresh} uses
9104 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9105 signing keys. OpenPGP signatures are checked against keys from this keyring;
9106 missing keys are downloaded to this keyring as well (see
9107 @option{--key-download} below.)
9109 You can export keys from your default GPG keyring into a keybox file using
9110 commands like this one:
9113 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9116 Likewise, you can fetch keys to a specific keybox file like this:
9119 gpg --no-default-keyring --keyring mykeyring.kbx \
9120 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9123 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9124 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9126 @item --key-download=@var{policy}
9127 Handle missing OpenPGP keys according to @var{policy}, which may be one
9132 Always download missing OpenPGP keys from the key server, and add them
9133 to the user's GnuPG keyring.
9136 Never try to download missing OpenPGP keys. Instead just bail out.
9139 When a package signed with an unknown OpenPGP key is encountered, ask
9140 the user whether to download it or not. This is the default behavior.
9143 @item --key-server=@var{host}
9144 Use @var{host} as the OpenPGP key server when importing a public key.
9148 The @code{github} updater uses the
9149 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9150 releases. When used repeatedly e.g.@: when refreshing all packages,
9151 GitHub will eventually refuse to answer any further API requests. By
9152 default 60 API requests per hour are allowed, and a full refresh on all
9153 GitHub packages in Guix requires more than this. Authentication with
9154 GitHub through the use of an API token alleviates these limits. To use
9155 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9156 token procured from @uref{https://github.com/settings/tokens} or
9160 @node Invoking guix lint
9161 @section Invoking @command{guix lint}
9163 @cindex @command{guix lint}
9164 @cindex package, checking for errors
9165 The @command{guix lint} command is meant to help package developers avoid
9166 common errors and use a consistent style. It runs a number of checks on
9167 a given set of packages in order to find common mistakes in their
9168 definitions. Available @dfn{checkers} include (see
9169 @code{--list-checkers} for a complete list):
9174 Validate certain typographical and stylistic rules about package
9175 descriptions and synopses.
9177 @item inputs-should-be-native
9178 Identify inputs that should most likely be native inputs.
9184 @itemx source-file-name
9185 Probe @code{home-page} and @code{source} URLs and report those that are
9186 invalid. Suggest a @code{mirror://} URL when applicable. If the
9187 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9188 URL. Check that the source file name is meaningful, e.g.@: is not just a
9189 version number or ``git-checkout'', without a declared @code{file-name}
9190 (@pxref{origin Reference}).
9192 @item source-unstable-tarball
9193 Parse the @code{source} URL to determine if a tarball from GitHub is
9194 autogenerated or if it is a release tarball. Unfortunately GitHub's
9195 autogenerated tarballs are sometimes regenerated.
9198 @cindex security vulnerabilities
9199 @cindex CVE, Common Vulnerabilities and Exposures
9200 Report known vulnerabilities found in the Common Vulnerabilities and
9201 Exposures (CVE) databases of the current and past year
9202 @uref{https://nvd.nist.gov/download.cfm#CVE_FEED, published by the US
9205 To view information about a particular vulnerability, visit pages such as:
9209 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9211 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9215 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9216 @code{CVE-2015-7554}.
9218 Package developers can specify in package recipes the
9219 @uref{https://nvd.nist.gov/cpe.cfm,Common Platform Enumeration (CPE)}
9220 name and version of the package when they differ from the name or version
9221 that Guix uses, as in this example:
9227 ;; CPE calls this package "grub2".
9228 (properties '((cpe-name . "grub2")
9229 (cpe-version . "2.3")))
9232 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9233 Some entries in the CVE database do not specify which version of a
9234 package they apply to, and would thus ``stick around'' forever. Package
9235 developers who found CVE alerts and verified they can be ignored can
9236 declare them as in this example:
9242 ;; These CVEs no longer apply and can be safely ignored.
9243 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9246 "CVE-2011-5244")))))
9250 Warn about obvious source code formatting issues: trailing white space,
9251 use of tabulations, etc.
9254 The general syntax is:
9257 guix lint @var{options} @var{package}@dots{}
9260 If no package is given on the command line, then all packages are checked.
9261 The @var{options} may be zero or more of the following:
9264 @item --list-checkers
9266 List and describe all the available checkers that will be run on packages
9271 Only enable the checkers specified in a comma-separated list using the
9272 names returned by @code{--list-checkers}.
9276 @node Invoking guix size
9277 @section Invoking @command{guix size}
9280 @cindex package size
9282 @cindex @command{guix size}
9283 The @command{guix size} command helps package developers profile the
9284 disk usage of packages. It is easy to overlook the impact of an
9285 additional dependency added to a package, or the impact of using a
9286 single output for a package that could easily be split (@pxref{Packages
9287 with Multiple Outputs}). Such are the typical issues that
9288 @command{guix size} can highlight.
9290 The command can be passed one or more package specifications
9291 such as @code{gcc@@4.8}
9292 or @code{guile:debug}, or a file name in the store. Consider this
9296 $ guix size coreutils
9297 store item total self
9298 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9299 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9300 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9301 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9302 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9303 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9304 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9305 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9310 The store items listed here constitute the @dfn{transitive closure} of
9311 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9312 would be returned by:
9315 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9318 Here the output shows three columns next to store items. The first column,
9319 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9320 the store item---that is, its own size plus the size of all its
9321 dependencies. The next column, labeled ``self'', shows the size of the
9322 item itself. The last column shows the ratio of the size of the item
9323 itself to the space occupied by all the items listed here.
9325 In this example, we see that the closure of Coreutils weighs in at
9326 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9327 libraries. (That libc and GCC's libraries represent a large fraction of
9328 the closure is not a problem @i{per se} because they are always available
9329 on the system anyway.)
9331 When the package(s) passed to @command{guix size} are available in the
9332 store@footnote{More precisely, @command{guix size} looks for the
9333 @emph{ungrafted} variant of the given package(s), as returned by
9334 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9335 for information on grafts.}, @command{guix size} queries the daemon to determine its
9336 dependencies, and measures its size in the store, similar to @command{du
9337 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9340 When the given packages are @emph{not} in the store, @command{guix size}
9341 reports information based on the available substitutes
9342 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9343 store items that are not even on disk, only available remotely.
9345 You can also specify several package names:
9348 $ guix size coreutils grep sed bash
9349 store item total self
9350 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9351 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9352 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9353 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9359 In this example we see that the combination of the four packages takes
9360 102.3@tie{}MiB in total, which is much less than the sum of each closure
9361 since they have a lot of dependencies in common.
9363 The available options are:
9367 @item --substitute-urls=@var{urls}
9368 Use substitute information from @var{urls}.
9369 @xref{client-substitute-urls, the same option for @code{guix build}}.
9371 @item --sort=@var{key}
9372 Sort lines according to @var{key}, one of the following options:
9376 the size of each item (the default);
9378 the total size of the item's closure.
9381 @item --map-file=@var{file}
9382 Write a graphical map of disk usage in PNG format to @var{file}.
9384 For the example above, the map looks like this:
9386 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
9387 produced by @command{guix size}}
9389 This option requires that
9390 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
9391 installed and visible in Guile's module search path. When that is not
9392 the case, @command{guix size} fails as it tries to load it.
9394 @item --system=@var{system}
9395 @itemx -s @var{system}
9396 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
9400 @node Invoking guix graph
9401 @section Invoking @command{guix graph}
9404 @cindex @command{guix graph}
9405 @cindex package dependencies
9406 Packages and their dependencies form a @dfn{graph}, specifically a
9407 directed acyclic graph (DAG). It can quickly become difficult to have a
9408 mental model of the package DAG, so the @command{guix graph} command
9409 provides a visual representation of the DAG. By default,
9410 @command{guix graph} emits a DAG representation in the input format of
9411 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
9412 directly to the @command{dot} command of Graphviz. It can also emit an
9413 HTML page with embedded JavaScript code to display a ``chord diagram''
9414 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
9415 emit Cypher queries to construct a graph in a graph database supporting
9416 the @uref{https://www.opencypher.org/, openCypher} query language.
9417 The general syntax is:
9420 guix graph @var{options} @var{package}@dots{}
9423 For example, the following command generates a PDF file representing the
9424 package DAG for the GNU@tie{}Core Utilities, showing its build-time
9428 guix graph coreutils | dot -Tpdf > dag.pdf
9431 The output looks like this:
9433 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
9435 Nice little graph, no?
9437 But there is more than one graph! The one above is concise: it is the
9438 graph of package objects, omitting implicit inputs such as GCC, libc,
9439 grep, etc. It is often useful to have such a concise graph, but
9440 sometimes one may want to see more details. @command{guix graph} supports
9441 several types of graphs, allowing you to choose the level of detail:
9445 This is the default type used in the example above. It shows the DAG of
9446 package objects, excluding implicit dependencies. It is concise, but
9447 filters out many details.
9449 @item reverse-package
9450 This shows the @emph{reverse} DAG of packages. For example:
9453 guix graph --type=reverse-package ocaml
9456 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
9457 you are also interested in cases where OCaml is an implicit dependency, see
9458 @code{reverse-bag} below.)
9460 Note that for core packages this can yield huge graphs. If all you want
9461 is to know the number of packages that depend on a given package, use
9462 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
9463 @option{--list-dependent}}).
9466 This is the package DAG, @emph{including} implicit inputs.
9468 For instance, the following command:
9471 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
9474 ...@: yields this bigger graph:
9476 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
9478 At the bottom of the graph, we see all the implicit inputs of
9479 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
9481 Now, note that the dependencies of these implicit inputs---that is, the
9482 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
9483 here, for conciseness.
9486 Similar to @code{bag-emerged}, but this time including all the bootstrap
9489 @item bag-with-origins
9490 Similar to @code{bag}, but also showing origins and their dependencies.
9493 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
9494 it also takes implicit dependencies into account. For example:
9497 guix graph -t reverse-bag dune
9501 ...@: yields the graph of all packages that depend on Dune, directly or
9502 indirectly. Since Dune is an @emph{implicit} dependency of many packages
9503 @i{via} @code{dune-build-system}, this shows a large number of packages,
9504 whereas @code{reverse-package} would show very few if any.
9507 This is the most detailed representation: It shows the DAG of
9508 derivations (@pxref{Derivations}) and plain store items. Compared to
9509 the above representation, many additional nodes are visible, including
9510 build scripts, patches, Guile modules, etc.
9512 For this type of graph, it is also possible to pass a @file{.drv} file
9513 name instead of a package name, as in:
9516 guix graph -t derivation `guix system build -d my-config.scm`
9520 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
9521 For example, the following command shows the graph for the package
9522 module that defines the @code{guile} package:
9525 guix graph -t module guile | dot -Tpdf > module-graph.pdf
9529 All the types above correspond to @emph{build-time dependencies}. The
9530 following graph type represents the @emph{run-time dependencies}:
9534 This is the graph of @dfn{references} of a package output, as returned
9535 by @command{guix gc --references} (@pxref{Invoking guix gc}).
9537 If the given package output is not available in the store, @command{guix
9538 graph} attempts to obtain dependency information from substitutes.
9540 Here you can also pass a store file name instead of a package name. For
9541 example, the command below produces the reference graph of your profile
9542 (which can be big!):
9545 guix graph -t references `readlink -f ~/.guix-profile`
9549 This is the graph of the @dfn{referrers} of a store item, as returned by
9550 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
9552 This relies exclusively on local information from your store. For
9553 instance, let us suppose that the current Inkscape is available in 10
9554 profiles on your machine; @command{guix graph -t referrers inkscape}
9555 will show a graph rooted at Inkscape and with those 10 profiles linked
9558 It can help determine what is preventing a store item from being garbage
9563 The available options are the following:
9566 @item --type=@var{type}
9567 @itemx -t @var{type}
9568 Produce a graph output of @var{type}, where @var{type} must be one of
9569 the values listed above.
9572 List the supported graph types.
9574 @item --backend=@var{backend}
9575 @itemx -b @var{backend}
9576 Produce a graph using the selected @var{backend}.
9578 @item --list-backends
9579 List the supported graph backends.
9581 Currently, the available backends are Graphviz and d3.js.
9583 @item --expression=@var{expr}
9584 @itemx -e @var{expr}
9585 Consider the package @var{expr} evaluates to.
9587 This is useful to precisely refer to a package, as in this example:
9590 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
9593 @item --system=@var{system}
9594 @itemx -s @var{system}
9595 Display the graph for @var{system}---e.g., @code{i686-linux}.
9597 The package dependency graph is largely architecture-independent, but there
9598 are some architecture-dependent bits that this option allows you to visualize.
9603 @node Invoking guix publish
9604 @section Invoking @command{guix publish}
9606 @cindex @command{guix publish}
9607 The purpose of @command{guix publish} is to enable users to easily share
9608 their store with others, who can then use it as a substitute server
9609 (@pxref{Substitutes}).
9611 When @command{guix publish} runs, it spawns an HTTP server which allows
9612 anyone with network access to obtain substitutes from it. This means
9613 that any machine running Guix can also act as if it were a build farm,
9614 since the HTTP interface is compatible with Hydra, the software behind
9615 the @code{@value{SUBSTITUTE-SERVER}} build farm.
9617 For security, each substitute is signed, allowing recipients to check
9618 their authenticity and integrity (@pxref{Substitutes}). Because
9619 @command{guix publish} uses the signing key of the system, which is only
9620 readable by the system administrator, it must be started as root; the
9621 @code{--user} option makes it drop root privileges early on.
9623 The signing key pair must be generated before @command{guix publish} is
9624 launched, using @command{guix archive --generate-key} (@pxref{Invoking
9627 The general syntax is:
9630 guix publish @var{options}@dots{}
9633 Running @command{guix publish} without any additional arguments will
9634 spawn an HTTP server on port 8080:
9640 Once a publishing server has been authorized (@pxref{Invoking guix
9641 archive}), the daemon may download substitutes from it:
9644 guix-daemon --substitute-urls=http://example.org:8080
9647 By default, @command{guix publish} compresses archives on the fly as it
9648 serves them. This ``on-the-fly'' mode is convenient in that it requires
9649 no setup and is immediately available. However, when serving lots of
9650 clients, we recommend using the @option{--cache} option, which enables
9651 caching of the archives before they are sent to clients---see below for
9652 details. The @command{guix weather} command provides a handy way to
9653 check what a server provides (@pxref{Invoking guix weather}).
9655 As a bonus, @command{guix publish} also serves as a content-addressed
9656 mirror for source files referenced in @code{origin} records
9657 (@pxref{origin Reference}). For instance, assuming @command{guix
9658 publish} is running on @code{example.org}, the following URL returns the
9659 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
9660 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
9663 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
9666 Obviously, these URLs only work for files that are in the store; in
9667 other cases, they return 404 (``Not Found'').
9669 @cindex build logs, publication
9670 Build logs are available from @code{/log} URLs like:
9673 http://example.org/log/gwspk@dots{}-guile-2.2.3
9677 When @command{guix-daemon} is configured to save compressed build logs,
9678 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
9679 URLs return the compressed log as-is, with an appropriate
9680 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
9681 running @command{guix-daemon} with @code{--log-compression=gzip} since
9682 Web browsers can automatically decompress it, which is not the case with
9685 The following options are available:
9688 @item --port=@var{port}
9689 @itemx -p @var{port}
9690 Listen for HTTP requests on @var{port}.
9692 @item --listen=@var{host}
9693 Listen on the network interface for @var{host}. The default is to
9694 accept connections from any interface.
9696 @item --user=@var{user}
9697 @itemx -u @var{user}
9698 Change privileges to @var{user} as soon as possible---i.e., once the
9699 server socket is open and the signing key has been read.
9701 @item --compression[=@var{method}[:@var{level}]]
9702 @itemx -C [@var{method}[:@var{level}]]
9703 Compress data using the given @var{method} and @var{level}. @var{method} is
9704 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
9707 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
9708 to different compression levels: 1 is the fastest, and 9 is the best
9709 (CPU-intensive). The default is 3.
9711 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
9712 increase in CPU usage; see
9713 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
9716 Unless @option{--cache} is used, compression occurs on the fly and
9717 the compressed streams are not
9718 cached. Thus, to reduce load on the machine that runs @command{guix
9719 publish}, it may be a good idea to choose a low compression level, to
9720 run @command{guix publish} behind a caching proxy, or to use
9721 @option{--cache}. Using @option{--cache} has the advantage that it
9722 allows @command{guix publish} to add @code{Content-Length} HTTP header
9725 This option can be repeated, in which case every substitute gets compressed
9726 using all the selected methods, and all of them are advertised. This is
9727 useful when users may not support all the compression methods: they can select
9728 the one they support.
9730 @item --cache=@var{directory}
9731 @itemx -c @var{directory}
9732 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
9733 and only serve archives that are in cache.
9735 When this option is omitted, archives and meta-data are created
9736 on-the-fly. This can reduce the available bandwidth, especially when
9737 compression is enabled, since this may become CPU-bound. Another
9738 drawback of the default mode is that the length of archives is not known
9739 in advance, so @command{guix publish} does not add a
9740 @code{Content-Length} HTTP header to its responses, which in turn
9741 prevents clients from knowing the amount of data being downloaded.
9743 Conversely, when @option{--cache} is used, the first request for a store
9744 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
9745 background process to @dfn{bake} the archive---computing its
9746 @code{.narinfo} and compressing the archive, if needed. Once the
9747 archive is cached in @var{directory}, subsequent requests succeed and
9748 are served directly from the cache, which guarantees that clients get
9749 the best possible bandwidth.
9751 The ``baking'' process is performed by worker threads. By default, one
9752 thread per CPU core is created, but this can be customized. See
9753 @option{--workers} below.
9755 When @option{--ttl} is used, cached entries are automatically deleted
9756 when they have expired.
9758 @item --workers=@var{N}
9759 When @option{--cache} is used, request the allocation of @var{N} worker
9760 threads to ``bake'' archives.
9762 @item --ttl=@var{ttl}
9763 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
9764 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
9765 days, @code{1m} means 1 month, and so on.
9767 This allows the user's Guix to keep substitute information in cache for
9768 @var{ttl}. However, note that @code{guix publish} does not itself
9769 guarantee that the store items it provides will indeed remain available
9770 for as long as @var{ttl}.
9772 Additionally, when @option{--cache} is used, cached entries that have
9773 not been accessed for @var{ttl} and that no longer have a corresponding
9774 item in the store, may be deleted.
9776 @item --nar-path=@var{path}
9777 Use @var{path} as the prefix for the URLs of ``nar'' files
9778 (@pxref{Invoking guix archive, normalized archives}).
9780 By default, nars are served at a URL such as
9781 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
9782 change the @code{/nar} part to @var{path}.
9784 @item --public-key=@var{file}
9785 @itemx --private-key=@var{file}
9786 Use the specific @var{file}s as the public/private key pair used to sign
9787 the store items being published.
9789 The files must correspond to the same key pair (the private key is used
9790 for signing and the public key is merely advertised in the signature
9791 metadata). They must contain keys in the canonical s-expression format
9792 as produced by @command{guix archive --generate-key} (@pxref{Invoking
9793 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
9794 @file{/etc/guix/signing-key.sec} are used.
9796 @item --repl[=@var{port}]
9797 @itemx -r [@var{port}]
9798 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
9799 Reference Manual}) on @var{port} (37146 by default). This is used
9800 primarily for debugging a running @command{guix publish} server.
9803 Enabling @command{guix publish} on Guix System is a one-liner: just
9804 instantiate a @code{guix-publish-service-type} service in the @code{services} field
9805 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
9806 @code{guix-publish-service-type}}).
9808 If you are instead running Guix on a ``foreign distro'', follow these
9813 If your host distro uses the systemd init system:
9816 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
9817 /etc/systemd/system/
9818 # systemctl start guix-publish && systemctl enable guix-publish
9822 If your host distro uses the Upstart init system:
9825 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
9826 # start guix-publish
9830 Otherwise, proceed similarly with your distro's init system.
9833 @node Invoking guix challenge
9834 @section Invoking @command{guix challenge}
9836 @cindex reproducible builds
9837 @cindex verifiable builds
9838 @cindex @command{guix challenge}
9840 Do the binaries provided by this server really correspond to the source
9841 code it claims to build? Is a package build process deterministic?
9842 These are the questions the @command{guix challenge} command attempts to
9845 The former is obviously an important question: Before using a substitute
9846 server (@pxref{Substitutes}), one had better @emph{verify} that it
9847 provides the right binaries, and thus @emph{challenge} it. The latter
9848 is what enables the former: If package builds are deterministic, then
9849 independent builds of the package should yield the exact same result,
9850 bit for bit; if a server provides a binary different from the one
9851 obtained locally, it may be either corrupt or malicious.
9853 We know that the hash that shows up in @file{/gnu/store} file names is
9854 the hash of all the inputs of the process that built the file or
9855 directory---compilers, libraries, build scripts,
9856 etc. (@pxref{Introduction}). Assuming deterministic build processes,
9857 one store file name should map to exactly one build output.
9858 @command{guix challenge} checks whether there is, indeed, a single
9859 mapping by comparing the build outputs of several independent builds of
9860 any given store item.
9862 The command output looks like this:
9865 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
9866 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
9867 updating list of substitutes from 'https://guix.example.org'... 100.0%
9868 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
9869 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9870 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
9871 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
9872 /gnu/store/@dots{}-git-2.5.0 contents differ:
9873 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
9874 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
9875 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
9876 /gnu/store/@dots{}-pius-2.1.1 contents differ:
9877 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9878 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
9879 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
9883 6,406 store items were analyzed:
9884 - 4,749 (74.1%) were identical
9885 - 525 (8.2%) differed
9886 - 1,132 (17.7%) were inconclusive
9890 In this example, @command{guix challenge} first scans the store to
9891 determine the set of locally-built derivations---as opposed to store
9892 items that were downloaded from a substitute server---and then queries
9893 all the substitute servers. It then reports those store items for which
9894 the servers obtained a result different from the local build.
9896 @cindex non-determinism, in package builds
9897 As an example, @code{guix.example.org} always gets a different answer.
9898 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
9899 case of Git. This might indicate that the build process of Git is
9900 non-deterministic, meaning that its output varies as a function of
9901 various things that Guix does not fully control, in spite of building
9902 packages in isolated environments (@pxref{Features}). Most common
9903 sources of non-determinism include the addition of timestamps in build
9904 results, the inclusion of random numbers, and directory listings sorted
9905 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
9908 To find out what is wrong with this Git binary, we can do something along
9909 these lines (@pxref{Invoking guix archive}):
9912 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0 \
9913 | guix archive -x /tmp/git
9914 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
9917 This command shows the difference between the files resulting from the
9918 local build, and the files resulting from the build on
9919 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
9920 diffutils, Comparing and Merging Files}). The @command{diff} command
9921 works great for text files. When binary files differ, a better option
9922 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
9923 visualize differences for all kinds of files.
9925 Once you have done that work, you can tell whether the differences are due
9926 to a non-deterministic build process or to a malicious server. We try
9927 hard to remove sources of non-determinism in packages to make it easier
9928 to verify substitutes, but of course, this is a process that
9929 involves not just Guix, but a large part of the free software community.
9930 In the meantime, @command{guix challenge} is one tool to help address
9933 If you are writing packages for Guix, you are encouraged to check
9934 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
9935 same build result as you did with:
9938 $ guix challenge @var{package}
9942 where @var{package} is a package specification such as
9943 @code{guile@@2.0} or @code{glibc:debug}.
9945 The general syntax is:
9948 guix challenge @var{options} [@var{packages}@dots{}]
9951 When a difference is found between the hash of a locally-built item and
9952 that of a server-provided substitute, or among substitutes provided by
9953 different servers, the command displays it as in the example above and
9954 its exit code is 2 (other non-zero exit codes denote other kinds of
9957 The one option that matters is:
9961 @item --substitute-urls=@var{urls}
9962 Consider @var{urls} the whitespace-separated list of substitute source
9967 Show details about matches (identical contents) in addition to
9968 information about mismatches.
9972 @node Invoking guix copy
9973 @section Invoking @command{guix copy}
9975 @cindex copy, of store items, over SSH
9976 @cindex SSH, copy of store items
9977 @cindex sharing store items across machines
9978 @cindex transferring store items across machines
9979 The @command{guix copy} command copies items from the store of one
9980 machine to that of another machine over a secure shell (SSH)
9981 connection@footnote{This command is available only when Guile-SSH was
9982 found. @xref{Requirements}, for details.}. For example, the following
9983 command copies the @code{coreutils} package, the user's profile, and all
9984 their dependencies over to @var{host}, logged in as @var{user}:
9987 guix copy --to=@var{user}@@@var{host} \
9988 coreutils `readlink -f ~/.guix-profile`
9991 If some of the items to be copied are already present on @var{host},
9992 they are not actually sent.
9994 The command below retrieves @code{libreoffice} and @code{gimp} from
9995 @var{host}, assuming they are available there:
9998 guix copy --from=@var{host} libreoffice gimp
10001 The SSH connection is established using the Guile-SSH client, which is
10002 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10003 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10005 The key used to sign items that are sent must be accepted by the remote
10006 machine. Likewise, the key used by the remote machine to sign items you
10007 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10008 own daemon. @xref{Invoking guix archive}, for more information about
10009 store item authentication.
10011 The general syntax is:
10014 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10017 You must always specify one of the following options:
10020 @item --to=@var{spec}
10021 @itemx --from=@var{spec}
10022 Specify the host to send to or receive from. @var{spec} must be an SSH
10023 spec such as @code{example.org}, @code{charlie@@example.org}, or
10024 @code{charlie@@example.org:2222}.
10027 The @var{items} can be either package names, such as @code{gimp}, or
10028 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10030 When specifying the name of a package to send, it is first built if
10031 needed, unless @option{--dry-run} was specified. Common build options
10032 are supported (@pxref{Common Build Options}).
10035 @node Invoking guix container
10036 @section Invoking @command{guix container}
10038 @cindex @command{guix container}
10040 As of version @value{VERSION}, this tool is experimental. The interface
10041 is subject to radical change in the future.
10044 The purpose of @command{guix container} is to manipulate processes
10045 running within an isolated environment, commonly known as a
10046 ``container'', typically created by the @command{guix environment}
10047 (@pxref{Invoking guix environment}) and @command{guix system container}
10048 (@pxref{Invoking guix system}) commands.
10050 The general syntax is:
10053 guix container @var{action} @var{options}@dots{}
10056 @var{action} specifies the operation to perform with a container, and
10057 @var{options} specifies the context-specific arguments for the action.
10059 The following actions are available:
10063 Execute a command within the context of a running container.
10068 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10071 @var{pid} specifies the process ID of the running container.
10072 @var{program} specifies an executable file name within the root file
10073 system of the container. @var{arguments} are the additional options that
10074 will be passed to @var{program}.
10076 The following command launches an interactive login shell inside a
10077 Guix system container, started by @command{guix system container}, and whose
10078 process ID is 9001:
10081 guix container exec 9001 /run/current-system/profile/bin/bash --login
10084 Note that the @var{pid} cannot be the parent process of a container. It
10085 must be PID 1 of the container or one of its child processes.
10089 @node Invoking guix weather
10090 @section Invoking @command{guix weather}
10092 Occasionally you're grumpy because substitutes are lacking and you end
10093 up building packages by yourself (@pxref{Substitutes}). The
10094 @command{guix weather} command reports on substitute availability on the
10095 specified servers so you can have an idea of whether you'll be grumpy
10096 today. It can sometimes be useful info as a user, but it is primarily
10097 useful to people running @command{guix publish} (@pxref{Invoking guix
10100 @cindex statistics, for substitutes
10101 @cindex availability of substitutes
10102 @cindex substitute availability
10103 @cindex weather, substitute availability
10104 Here's a sample run:
10107 $ guix weather --substitute-urls=https://guix.example.org
10108 computing 5,872 package derivations for x86_64-linux...
10109 looking for 6,128 store items on https://guix.example.org..
10110 updating list of substitutes from 'https://guix.example.org'... 100.0%
10111 https://guix.example.org
10112 43.4% substitutes available (2,658 out of 6,128)
10113 7,032.5 MiB of nars (compressed)
10114 19,824.2 MiB on disk (uncompressed)
10115 0.030 seconds per request (182.9 seconds in total)
10116 33.5 requests per second
10118 9.8% (342 out of 3,470) of the missing items are queued
10120 x86_64-linux: 518 (59.7%)
10121 i686-linux: 221 (25.5%)
10122 aarch64-linux: 128 (14.8%)
10123 build rate: 23.41 builds per hour
10124 x86_64-linux: 11.16 builds per hour
10125 i686-linux: 6.03 builds per hour
10126 aarch64-linux: 6.41 builds per hour
10129 @cindex continuous integration, statistics
10130 As you can see, it reports the fraction of all the packages for which
10131 substitutes are available on the server---regardless of whether
10132 substitutes are enabled, and regardless of whether this server's signing
10133 key is authorized. It also reports the size of the compressed archives
10134 (``nars'') provided by the server, the size the corresponding store
10135 items occupy in the store (assuming deduplication is turned off), and
10136 the server's throughput. The second part gives continuous integration
10137 (CI) statistics, if the server supports it. In addition, using the
10138 @option{--coverage} option, @command{guix weather} can list ``important''
10139 package substitutes missing on the server (see below).
10141 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10142 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10143 challenge}, it ignores signatures on those substitutes, which is
10144 innocuous since the command only gathers statistics and cannot install
10147 The general syntax is:
10150 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10153 When @var{packages} is omitted, @command{guix weather} checks the availability
10154 of substitutes for @emph{all} the packages, or for those specified with
10155 @option{--manifest}; otherwise it only considers the specified packages. It
10156 is also possible to query specific system types with @option{--system}. The
10157 available options are listed below.
10160 @item --substitute-urls=@var{urls}
10161 @var{urls} is the space-separated list of substitute server URLs to
10162 query. When this option is omitted, the default set of substitute
10163 servers is queried.
10165 @item --system=@var{system}
10166 @itemx -s @var{system}
10167 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10168 option can be repeated, in which case @command{guix weather} will query
10169 substitutes for several system types.
10171 @item --manifest=@var{file}
10172 Instead of querying substitutes for all the packages, only ask for those
10173 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10174 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10177 @item --coverage[=@var{count}]
10178 @itemx -c [@var{count}]
10179 Report on substitute coverage for packages: list packages with at least
10180 @var{count} dependents (zero by default) for which substitutes are
10181 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10182 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10183 @var{b} usually lacks substitutes as well. The result looks like this:
10186 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10187 computing 8,983 package derivations for x86_64-linux...
10188 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10189 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10190 @value{SUBSTITUTE-URL}
10191 64.7% substitutes available (6,047 out of 9,343)
10193 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10194 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10195 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10196 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10200 What this example shows is that @code{kcoreaddons} and presumably the 58
10201 packages that depend on it have no substitutes at @code{ci.guix.info};
10202 likewise for @code{qgpgme} and the 46 packages that depend on it.
10204 If you are a Guix developer, or if you are taking care of this build farm,
10205 you'll probably want to have a closer look at these packages: they may simply
10209 @node Invoking guix processes
10210 @section Invoking @command{guix processes}
10212 The @command{guix processes} command can be useful to developers and system
10213 administrators, especially on multi-user machines and on build farms: it lists
10214 the current sessions (connections to the daemon), as well as information about
10215 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10216 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10217 listed.}. Here's an example of the information it returns:
10220 $ sudo guix processes
10223 ClientCommand: guix environment --ad-hoc python
10227 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10231 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10232 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10233 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10234 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10235 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10236 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10237 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10240 In this example we see that @command{guix-daemon} has three clients:
10241 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10242 integration tool; their process identifier (PID) is given by the
10243 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10244 @command{guix-daemon} sub-process of this particular session.
10246 The @code{LockHeld} fields show which store items are currently locked by this
10247 session, which corresponds to store items being built or substituted (the
10248 @code{LockHeld} field is not displayed when @command{guix processes} is not
10249 running as root.) Last, by looking at the @code{ChildProcess} field, we
10250 understand that these three builds are being offloaded (@pxref{Daemon Offload
10253 The output is in Recutils format so we can use the handy @command{recsel}
10254 command to select sessions of interest (@pxref{Selection Expressions,,,
10255 recutils, GNU recutils manual}). As an example, the command shows the command
10256 line and PID of the client that triggered the build of a Perl package:
10259 $ sudo guix processes | \
10260 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10262 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10266 @node System Configuration
10267 @chapter System Configuration
10269 @cindex system configuration
10270 Guix System supports a consistent whole-system configuration
10271 mechanism. By that we mean that all aspects of the global system
10272 configuration---such as the available system services, timezone and
10273 locale settings, user accounts---are declared in a single place. Such
10274 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10276 One of the advantages of putting all the system configuration under the
10277 control of Guix is that it supports transactional system upgrades, and
10278 makes it possible to roll back to a previous system instantiation,
10279 should something go wrong with the new one (@pxref{Features}). Another
10280 advantage is that it makes it easy to replicate the exact same configuration
10281 across different machines, or at different points in time, without
10282 having to resort to additional administration tools layered on top of
10283 the own tools of the system.
10284 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10286 This section describes this mechanism. First we focus on the system
10287 administrator's viewpoint---explaining how the system is configured and
10288 instantiated. Then we show how this mechanism can be extended, for
10289 instance to support new system services.
10292 * Using the Configuration System:: Customizing your GNU system.
10293 * operating-system Reference:: Detail of operating-system declarations.
10294 * File Systems:: Configuring file system mounts.
10295 * Mapped Devices:: Block device extra processing.
10296 * User Accounts:: Specifying user accounts.
10297 * Keyboard Layout:: How the system interprets key strokes.
10298 * Locales:: Language and cultural convention settings.
10299 * Services:: Specifying system services.
10300 * Setuid Programs:: Programs running with root privileges.
10301 * X.509 Certificates:: Authenticating HTTPS servers.
10302 * Name Service Switch:: Configuring libc's name service switch.
10303 * Initial RAM Disk:: Linux-Libre bootstrapping.
10304 * Bootloader Configuration:: Configuring the boot loader.
10305 * Invoking guix system:: Instantiating a system configuration.
10306 * Running Guix in a VM:: How to run Guix System in a virtual machine.
10307 * Defining Services:: Adding new service definitions.
10310 @node Using the Configuration System
10311 @section Using the Configuration System
10313 The operating system is configured by providing an
10314 @code{operating-system} declaration in a file that can then be passed to
10315 the @command{guix system} command (@pxref{Invoking guix system}). A
10316 simple setup, with the default system services, the default Linux-Libre
10317 kernel, initial RAM disk, and boot loader looks like this:
10319 @findex operating-system
10321 @include os-config-bare-bones.texi
10324 This example should be self-describing. Some of the fields defined
10325 above, such as @code{host-name} and @code{bootloader}, are mandatory.
10326 Others, such as @code{packages} and @code{services}, can be omitted, in
10327 which case they get a default value.
10329 Below we discuss the effect of some of the most important fields
10330 (@pxref{operating-system Reference}, for details about all the available
10331 fields), and how to @dfn{instantiate} the operating system using
10332 @command{guix system}.
10334 @unnumberedsubsec Bootloader
10336 @cindex legacy boot, on Intel machines
10337 @cindex BIOS boot, on Intel machines
10340 The @code{bootloader} field describes the method that will be used to boot
10341 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
10342 mode, as in the example above. However, more recent machines rely instead on
10343 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
10344 the @code{bootloader} field should contain something along these lines:
10347 (bootloader-configuration
10348 (bootloader grub-efi-bootloader)
10349 (target "/boot/efi"))
10352 @xref{Bootloader Configuration}, for more information on the available
10353 configuration options.
10355 @unnumberedsubsec Globally-Visible Packages
10357 @vindex %base-packages
10358 The @code{packages} field lists packages that will be globally visible
10359 on the system, for all user accounts---i.e., in every user's @code{PATH}
10360 environment variable---in addition to the per-user profiles
10361 (@pxref{Invoking guix package}). The @code{%base-packages} variable
10362 provides all the tools one would expect for basic user and administrator
10363 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
10364 the GNU Zile lightweight text editor, @command{find}, @command{grep},
10365 etc. The example above adds GNU@tie{}Screen to those,
10366 taken from the @code{(gnu packages screen)}
10367 module (@pxref{Package Modules}). The
10368 @code{(list package output)} syntax can be used to add a specific output
10372 (use-modules (gnu packages))
10373 (use-modules (gnu packages dns))
10377 (packages (cons (list bind "utils")
10381 @findex specification->package
10382 Referring to packages by variable name, like @code{bind} above, has
10383 the advantage of being unambiguous; it also allows typos and such to be
10384 diagnosed right away as ``unbound variables''. The downside is that one
10385 needs to know which module defines which package, and to augment the
10386 @code{use-package-modules} line accordingly. To avoid that, one can use
10387 the @code{specification->package} procedure of the @code{(gnu packages)}
10388 module, which returns the best package for a given name or name and
10392 (use-modules (gnu packages))
10396 (packages (append (map specification->package
10397 '("tcpdump" "htop" "gnupg@@2.0"))
10401 @unnumberedsubsec System Services
10404 @vindex %base-services
10405 The @code{services} field lists @dfn{system services} to be made
10406 available when the system starts (@pxref{Services}).
10407 The @code{operating-system} declaration above specifies that, in
10408 addition to the basic services, we want the OpenSSH secure shell
10409 daemon listening on port 2222 (@pxref{Networking Services,
10410 @code{openssh-service-type}}). Under the hood,
10411 @code{openssh-service-type} arranges so that @command{sshd} is started with the
10412 right command-line options, possibly with supporting configuration files
10413 generated as needed (@pxref{Defining Services}).
10415 @cindex customization, of services
10416 @findex modify-services
10417 Occasionally, instead of using the base services as is, you will want to
10418 customize them. To do this, use @code{modify-services} (@pxref{Service
10419 Reference, @code{modify-services}}) to modify the list.
10421 For example, suppose you want to modify @code{guix-daemon} and Mingetty
10422 (the console log-in) in the @code{%base-services} list (@pxref{Base
10423 Services, @code{%base-services}}). To do that, you can write the
10424 following in your operating system declaration:
10427 (define %my-services
10428 ;; My very own list of services.
10429 (modify-services %base-services
10430 (guix-service-type config =>
10431 (guix-configuration
10433 (use-substitutes? #f)
10434 (extra-options '("--gc-keep-derivations"))))
10435 (mingetty-service-type config =>
10436 (mingetty-configuration
10437 (inherit config)))))
10441 (services %my-services))
10444 This changes the configuration---i.e., the service parameters---of the
10445 @code{guix-service-type} instance, and that of all the
10446 @code{mingetty-service-type} instances in the @code{%base-services} list.
10447 Observe how this is accomplished: first, we arrange for the original
10448 configuration to be bound to the identifier @code{config} in the
10449 @var{body}, and then we write the @var{body} so that it evaluates to the
10450 desired configuration. In particular, notice how we use @code{inherit}
10451 to create a new configuration which has the same values as the old
10452 configuration, but with a few modifications.
10454 @cindex encrypted disk
10455 The configuration for a typical ``desktop'' usage, with an encrypted
10456 root partition, the X11 display
10457 server, GNOME and Xfce (users can choose which of these desktop
10458 environments to use at the log-in screen by pressing @kbd{F1}), network
10459 management, power management, and more, would look like this:
10462 @include os-config-desktop.texi
10465 A graphical system with a choice of lightweight window managers
10466 instead of full-blown desktop environments would look like this:
10469 @include os-config-lightweight-desktop.texi
10472 This example refers to the @file{/boot/efi} file system by its UUID,
10473 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
10474 as returned by the @command{blkid} command.
10476 @xref{Desktop Services}, for the exact list of services provided by
10477 @code{%desktop-services}. @xref{X.509 Certificates}, for background
10478 information about the @code{nss-certs} package that is used here.
10480 Again, @code{%desktop-services} is just a list of service objects. If
10481 you want to remove services from there, you can do so using the
10482 procedures for list filtering (@pxref{SRFI-1 Filtering and
10483 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
10484 following expression returns a list that contains all the services in
10485 @code{%desktop-services} minus the Avahi service:
10488 (remove (lambda (service)
10489 (eq? (service-kind service) avahi-service-type))
10493 @unnumberedsubsec Instantiating the System
10495 Assuming the @code{operating-system} declaration
10496 is stored in the @file{my-system-config.scm}
10497 file, the @command{guix system reconfigure my-system-config.scm} command
10498 instantiates that configuration, and makes it the default GRUB boot
10499 entry (@pxref{Invoking guix system}).
10501 The normal way to change the system configuration is by updating this
10502 file and re-running @command{guix system reconfigure}. One should never
10503 have to touch files in @file{/etc} or to run commands that modify the
10504 system state such as @command{useradd} or @command{grub-install}. In
10505 fact, you must avoid that since that would not only void your warranty
10506 but also prevent you from rolling back to previous versions of your
10507 system, should you ever need to.
10509 @cindex roll-back, of the operating system
10510 Speaking of roll-back, each time you run @command{guix system
10511 reconfigure}, a new @dfn{generation} of the system is created---without
10512 modifying or deleting previous generations. Old system generations get
10513 an entry in the bootloader boot menu, allowing you to boot them in case
10514 something went wrong with the latest generation. Reassuring, no? The
10515 @command{guix system list-generations} command lists the system
10516 generations available on disk. It is also possible to roll back the
10517 system via the commands @command{guix system roll-back} and
10518 @command{guix system switch-generation}.
10520 Although the @command{guix system reconfigure} command will not modify
10521 previous generations, you must take care when the current generation is not
10522 the latest (e.g., after invoking @command{guix system roll-back}), since
10523 the operation might overwrite a later generation (@pxref{Invoking guix
10526 @unnumberedsubsec The Programming Interface
10528 At the Scheme level, the bulk of an @code{operating-system} declaration
10529 is instantiated with the following monadic procedure (@pxref{The Store
10532 @deffn {Monadic Procedure} operating-system-derivation os
10533 Return a derivation that builds @var{os}, an @code{operating-system}
10534 object (@pxref{Derivations}).
10536 The output of the derivation is a single directory that refers to all
10537 the packages, configuration files, and other supporting files needed to
10538 instantiate @var{os}.
10541 This procedure is provided by the @code{(gnu system)} module. Along
10542 with @code{(gnu services)} (@pxref{Services}), this module contains the
10543 guts of Guix System. Make sure to visit it!
10546 @node operating-system Reference
10547 @section @code{operating-system} Reference
10549 This section summarizes all the options available in
10550 @code{operating-system} declarations (@pxref{Using the Configuration
10553 @deftp {Data Type} operating-system
10554 This is the data type representing an operating system configuration.
10555 By that, we mean all the global system configuration, not per-user
10556 configuration (@pxref{Using the Configuration System}).
10559 @item @code{kernel} (default: @var{linux-libre})
10560 The package object of the operating system kernel to use@footnote{Currently
10561 only the Linux-libre kernel is supported. In the future, it will be
10562 possible to use the GNU@tie{}Hurd.}.
10564 @item @code{kernel-arguments} (default: @code{'("quiet")})
10565 List of strings or gexps representing additional arguments to pass on
10566 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
10568 @item @code{bootloader}
10569 The system bootloader configuration object. @xref{Bootloader Configuration}.
10572 This is the label (a string) as it appears in the bootloader's menu entry.
10573 The default label includes the kernel name and version.
10575 @item @code{keyboard-layout} (default: @code{#f})
10576 This field specifies the keyboard layout to use in the console. It can be
10577 either @code{#f}, in which case the default keyboard layout is used (usually
10578 US English), or a @code{<keyboard-layout>} record.
10580 This keyboard layout is in effect as soon as the kernel has booted. For
10581 instance, it is the keyboard layout in effect when you type a passphrase if
10582 your root file system is on a @code{luks-device-mapping} mapped device
10583 (@pxref{Mapped Devices}).
10586 This does @emph{not} specify the keyboard layout used by the bootloader, nor
10587 that used by the graphical display server. @xref{Bootloader Configuration},
10588 for information on how to specify the bootloader's keyboard layout. @xref{X
10589 Window}, for information on how to specify the keyboard layout used by the X
10593 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
10595 @cindex initial RAM disk
10596 The list of Linux kernel modules that need to be available in the
10597 initial RAM disk. @xref{Initial RAM Disk}.
10599 @item @code{initrd} (default: @code{base-initrd})
10600 A procedure that returns an initial RAM disk for the Linux
10601 kernel. This field is provided to support low-level customization and
10602 should rarely be needed for casual use. @xref{Initial RAM Disk}.
10604 @item @code{firmware} (default: @code{%base-firmware})
10606 List of firmware packages loadable by the operating system kernel.
10608 The default includes firmware needed for Atheros- and Broadcom-based
10609 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
10610 respectively). @xref{Hardware Considerations}, for more info on
10611 supported hardware.
10613 @item @code{host-name}
10616 @item @code{hosts-file}
10618 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
10619 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
10620 Reference Manual}). The default is a file with entries for
10621 @code{localhost} and @var{host-name}.
10623 @item @code{mapped-devices} (default: @code{'()})
10624 A list of mapped devices. @xref{Mapped Devices}.
10626 @item @code{file-systems}
10627 A list of file systems. @xref{File Systems}.
10629 @item @code{swap-devices} (default: @code{'()})
10630 @cindex swap devices
10631 A list of strings identifying devices or files to be used for ``swap
10632 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
10633 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
10634 It is possible to specify a swap file in a file system on a mapped
10635 device, provided that the necessary device mapping and file system are
10636 also specified. @xref{Mapped Devices} and @ref{File Systems}.
10638 @item @code{users} (default: @code{%base-user-accounts})
10639 @itemx @code{groups} (default: @code{%base-groups})
10640 List of user accounts and groups. @xref{User Accounts}.
10642 If the @code{users} list lacks a user account with UID@tie{}0, a
10643 ``root'' account with UID@tie{}0 is automatically added.
10645 @item @code{skeletons} (default: @code{(default-skeletons)})
10646 A list target file name/file-like object tuples (@pxref{G-Expressions,
10647 file-like objects}). These are the skeleton files that will be added to
10648 the home directory of newly-created user accounts.
10650 For instance, a valid value may look like this:
10653 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
10654 (".guile" ,(plain-file "guile"
10655 "(use-modules (ice-9 readline))
10656 (activate-readline)")))
10659 @item @code{issue} (default: @code{%default-issue})
10660 A string denoting the contents of the @file{/etc/issue} file, which is
10661 displayed when users log in on a text console.
10663 @item @code{packages} (default: @code{%base-packages})
10664 The set of packages installed in the global profile, which is accessible
10665 at @file{/run/current-system/profile}.
10667 The default set includes core utilities and it is good practice to
10668 install non-core utilities in user profiles (@pxref{Invoking guix
10671 @item @code{timezone}
10672 A timezone identifying string---e.g., @code{"Europe/Paris"}.
10674 You can run the @command{tzselect} command to find out which timezone
10675 string corresponds to your region. Choosing an invalid timezone name
10676 causes @command{guix system} to fail.
10678 @item @code{locale} (default: @code{"en_US.utf8"})
10679 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
10680 Library Reference Manual}). @xref{Locales}, for more information.
10682 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
10683 The list of locale definitions to be compiled and that may be used at
10684 run time. @xref{Locales}.
10686 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
10687 The list of GNU@tie{}libc packages whose locale data and tools are used
10688 to build the locale definitions. @xref{Locales}, for compatibility
10689 considerations that justify this option.
10691 @item @code{name-service-switch} (default: @code{%default-nss})
10692 Configuration of the libc name service switch (NSS)---a
10693 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
10696 @item @code{services} (default: @code{%base-services})
10697 A list of service objects denoting system services. @xref{Services}.
10699 @cindex essential services
10700 @item @code{essential-services} (default: ...)
10701 The list of ``essential services''---i.e., things like instances of
10702 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
10703 Reference}), which are derived from the operating system definition itself.
10704 As a user you should @emph{never} need to touch this field.
10706 @item @code{pam-services} (default: @code{(base-pam-services)})
10708 @cindex pluggable authentication modules
10709 Linux @dfn{pluggable authentication module} (PAM) services.
10710 @c FIXME: Add xref to PAM services section.
10712 @item @code{setuid-programs} (default: @var{%setuid-programs})
10713 List of string-valued G-expressions denoting setuid programs.
10714 @xref{Setuid Programs}.
10716 @item @code{sudoers-file} (default: @var{%sudoers-specification})
10717 @cindex sudoers file
10718 The contents of the @file{/etc/sudoers} file as a file-like object
10719 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
10721 This file specifies which users can use the @command{sudo} command, what
10722 they are allowed to do, and what privileges they may gain. The default
10723 is that only @code{root} and members of the @code{wheel} group may use
10728 @deffn {Scheme Syntax} this-operating-system
10729 When used in the @emph{lexical scope} of an operating system field definition,
10730 this identifier resolves to the operating system being defined.
10732 The example below shows how to refer to the operating system being defined in
10733 the definition of the @code{label} field:
10736 (use-modules (gnu) (guix))
10740 (label (package-full-name
10741 (operating-system-kernel this-operating-system))))
10744 It is an error to refer to @code{this-operating-system} outside an operating
10751 @section File Systems
10753 The list of file systems to be mounted is specified in the
10754 @code{file-systems} field of the operating system declaration
10755 (@pxref{Using the Configuration System}). Each file system is declared
10756 using the @code{file-system} form, like this:
10760 (mount-point "/home")
10761 (device "/dev/sda3")
10765 As usual, some of the fields are mandatory---those shown in the example
10766 above---while others can be omitted. These are described below.
10768 @deftp {Data Type} file-system
10769 Objects of this type represent file systems to be mounted. They
10770 contain the following members:
10774 This is a string specifying the type of the file system---e.g.,
10777 @item @code{mount-point}
10778 This designates the place where the file system is to be mounted.
10780 @item @code{device}
10781 This names the ``source'' of the file system. It can be one of three
10782 things: a file system label, a file system UUID, or the name of a
10783 @file{/dev} node. Labels and UUIDs offer a way to refer to file
10784 systems without having to hard-code their actual device
10785 name@footnote{Note that, while it is tempting to use
10786 @file{/dev/disk/by-uuid} and similar device names to achieve the same
10787 result, this is not recommended: These special device nodes are created
10788 by the udev daemon and may be unavailable at the time the device is
10791 @findex file-system-label
10792 File system labels are created using the @code{file-system-label}
10793 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
10794 plain strings. Here's an example of a file system referred to by its
10795 label, as shown by the @command{e2label} command:
10799 (mount-point "/home")
10801 (device (file-system-label "my-home")))
10805 UUIDs are converted from their string representation (as shown by the
10806 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
10807 @code{uuid} form expects 16-byte UUIDs as defined in
10808 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
10809 form of UUID used by the ext2 family of file systems and others, but it
10810 is different from ``UUIDs'' found in FAT file systems, for instance.},
10815 (mount-point "/home")
10817 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
10820 When the source of a file system is a mapped device (@pxref{Mapped
10821 Devices}), its @code{device} field @emph{must} refer to the mapped
10822 device name---e.g., @file{"/dev/mapper/root-partition"}.
10823 This is required so that
10824 the system knows that mounting the file system depends on having the
10825 corresponding device mapping established.
10827 @item @code{flags} (default: @code{'()})
10828 This is a list of symbols denoting mount flags. Recognized flags
10829 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
10830 access to special files), @code{no-suid} (ignore setuid and setgid
10831 bits), @code{no-atime} (do not update file access times), and @code{no-exec}
10832 (disallow program execution). @xref{Mount-Unmount-Remount,,, libc, The GNU C
10833 Library Reference Manual}, for more information on these flags.
10835 @item @code{options} (default: @code{#f})
10836 This is either @code{#f}, or a string denoting mount options passed to the
10837 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
10838 Reference Manual}, for details and run @command{man 8 mount} for options for
10839 various file systems.
10841 @item @code{mount?} (default: @code{#t})
10842 This value indicates whether to automatically mount the file system when
10843 the system is brought up. When set to @code{#f}, the file system gets
10844 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
10845 is not automatically mounted.
10847 @item @code{needed-for-boot?} (default: @code{#f})
10848 This Boolean value indicates whether the file system is needed when
10849 booting. If that is true, then the file system is mounted when the
10850 initial RAM disk (initrd) is loaded. This is always the case, for
10851 instance, for the root file system.
10853 @item @code{check?} (default: @code{#t})
10854 This Boolean indicates whether the file system needs to be checked for
10855 errors before being mounted.
10857 @item @code{create-mount-point?} (default: @code{#f})
10858 When true, the mount point is created if it does not exist yet.
10860 @item @code{dependencies} (default: @code{'()})
10861 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
10862 representing file systems that must be mounted or mapped devices that
10863 must be opened before (and unmounted or closed after) this one.
10865 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
10866 a dependency of @file{/sys/fs/cgroup/cpu} and
10867 @file{/sys/fs/cgroup/memory}.
10869 Another example is a file system that depends on a mapped device, for
10870 example for an encrypted partition (@pxref{Mapped Devices}).
10874 The @code{(gnu system file-systems)} exports the following useful
10877 @defvr {Scheme Variable} %base-file-systems
10878 These are essential file systems that are required on normal systems,
10879 such as @var{%pseudo-terminal-file-system} and @var{%immutable-store} (see
10880 below.) Operating system declarations should always contain at least
10884 @defvr {Scheme Variable} %pseudo-terminal-file-system
10885 This is the file system to be mounted as @file{/dev/pts}. It supports
10886 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
10887 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
10888 Manual}). Pseudo-terminals are used by terminal emulators such as
10892 @defvr {Scheme Variable} %shared-memory-file-system
10893 This file system is mounted as @file{/dev/shm} and is used to support
10894 memory sharing across processes (@pxref{Memory-mapped I/O,
10895 @code{shm_open},, libc, The GNU C Library Reference Manual}).
10898 @defvr {Scheme Variable} %immutable-store
10899 This file system performs a read-only ``bind mount'' of
10900 @file{/gnu/store}, making it read-only for all the users including
10901 @code{root}. This prevents against accidental modification by software
10902 running as @code{root} or by system administrators.
10904 The daemon itself is still able to write to the store: it remounts it
10905 read-write in its own ``name space.''
10908 @defvr {Scheme Variable} %binary-format-file-system
10909 The @code{binfmt_misc} file system, which allows handling of arbitrary
10910 executable file types to be delegated to user space. This requires the
10911 @code{binfmt.ko} kernel module to be loaded.
10914 @defvr {Scheme Variable} %fuse-control-file-system
10915 The @code{fusectl} file system, which allows unprivileged users to mount
10916 and unmount user-space FUSE file systems. This requires the
10917 @code{fuse.ko} kernel module to be loaded.
10920 @node Mapped Devices
10921 @section Mapped Devices
10923 @cindex device mapping
10924 @cindex mapped devices
10925 The Linux kernel has a notion of @dfn{device mapping}: a block device,
10926 such as a hard disk partition, can be @dfn{mapped} into another device,
10927 usually in @code{/dev/mapper/},
10928 with additional processing over the data that flows through
10929 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
10930 concept of a ``mapped device'' and that of a file system: both boil down
10931 to @emph{translating} input/output operations made on a file to
10932 operations on its backing store. Thus, the Hurd implements mapped
10933 devices, like file systems, using the generic @dfn{translator} mechanism
10934 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
10935 typical example is encryption device mapping: all writes to the mapped
10936 device are encrypted, and all reads are deciphered, transparently.
10937 Guix extends this notion by considering any device or set of devices that
10938 are @dfn{transformed} in some way to create a new device; for instance,
10939 RAID devices are obtained by @dfn{assembling} several other devices, such
10940 as hard disks or partitions, into a new one that behaves as one partition.
10941 Other examples, not yet implemented, are LVM logical volumes.
10943 Mapped devices are declared using the @code{mapped-device} form,
10944 defined as follows; for examples, see below.
10946 @deftp {Data Type} mapped-device
10947 Objects of this type represent device mappings that will be made when
10948 the system boots up.
10952 This is either a string specifying the name of the block device to be mapped,
10953 such as @code{"/dev/sda3"}, or a list of such strings when several devices
10954 need to be assembled for creating a new one.
10957 This string specifies the name of the resulting mapped device. For
10958 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
10959 specifying @code{"my-partition"} leads to the creation of
10960 the @code{"/dev/mapper/my-partition"} device.
10961 For RAID devices of type @code{raid-device-mapping}, the full device name
10962 such as @code{"/dev/md0"} needs to be given.
10965 This must be a @code{mapped-device-kind} object, which specifies how
10966 @var{source} is mapped to @var{target}.
10970 @defvr {Scheme Variable} luks-device-mapping
10971 This defines LUKS block device encryption using the @command{cryptsetup}
10972 command from the package with the same name. It relies on the
10973 @code{dm-crypt} Linux kernel module.
10976 @defvr {Scheme Variable} raid-device-mapping
10977 This defines a RAID device, which is assembled using the @code{mdadm}
10978 command from the package with the same name. It requires a Linux kernel
10979 module for the appropriate RAID level to be loaded, such as @code{raid456}
10980 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
10983 @cindex disk encryption
10985 The following example specifies a mapping from @file{/dev/sda3} to
10986 @file{/dev/mapper/home} using LUKS---the
10987 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
10988 standard mechanism for disk encryption.
10989 The @file{/dev/mapper/home}
10990 device can then be used as the @code{device} of a @code{file-system}
10991 declaration (@pxref{File Systems}).
10995 (source "/dev/sda3")
10997 (type luks-device-mapping))
11000 Alternatively, to become independent of device numbering, one may obtain
11001 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11005 cryptsetup luksUUID /dev/sda3
11008 and use it as follows:
11012 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11014 (type luks-device-mapping))
11017 @cindex swap encryption
11018 It is also desirable to encrypt swap space, since swap space may contain
11019 sensitive data. One way to accomplish that is to use a swap file in a
11020 file system on a device mapped via LUKS encryption. In this way, the
11021 swap file is encrypted because the entire device is encrypted.
11022 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11024 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11025 may be declared as follows:
11029 (source (list "/dev/sda1" "/dev/sdb1"))
11030 (target "/dev/md0")
11031 (type raid-device-mapping))
11034 The @file{/dev/md0} device can then be used as the @code{device} of a
11035 @code{file-system} declaration (@pxref{File Systems}).
11036 Note that the RAID level need not be given; it is chosen during the
11037 initial creation and formatting of the RAID device and is determined
11038 automatically later.
11041 @node User Accounts
11042 @section User Accounts
11046 @cindex user accounts
11047 User accounts and groups are entirely managed through the
11048 @code{operating-system} declaration. They are specified with the
11049 @code{user-account} and @code{user-group} forms:
11055 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11056 "audio" ;sound card
11057 "video" ;video devices such as webcams
11058 "cdrom")) ;the good ol' CD-ROM
11059 (comment "Bob's sister")
11060 (home-directory "/home/alice"))
11063 When booting or upon completion of @command{guix system reconfigure},
11064 the system ensures that only the user accounts and groups specified in
11065 the @code{operating-system} declaration exist, and with the specified
11066 properties. Thus, account or group creations or modifications made by
11067 directly invoking commands such as @command{useradd} are lost upon
11068 reconfiguration or reboot. This ensures that the system remains exactly
11071 @deftp {Data Type} user-account
11072 Objects of this type represent user accounts. The following members may
11077 The name of the user account.
11081 This is the name (a string) or identifier (a number) of the user group
11082 this account belongs to.
11084 @item @code{supplementary-groups} (default: @code{'()})
11085 Optionally, this can be defined as a list of group names that this
11086 account belongs to.
11088 @item @code{uid} (default: @code{#f})
11089 This is the user ID for this account (a number), or @code{#f}. In the
11090 latter case, a number is automatically chosen by the system when the
11091 account is created.
11093 @item @code{comment} (default: @code{""})
11094 A comment about the account, such as the account owner's full name.
11096 @item @code{home-directory}
11097 This is the name of the home directory for the account.
11099 @item @code{create-home-directory?} (default: @code{#t})
11100 Indicates whether the home directory of this account should be created
11101 if it does not exist yet.
11103 @item @code{shell} (default: Bash)
11104 This is a G-expression denoting the file name of a program to be used as
11105 the shell (@pxref{G-Expressions}).
11107 @item @code{system?} (default: @code{#f})
11108 This Boolean value indicates whether the account is a ``system''
11109 account. System accounts are sometimes treated specially; for instance,
11110 graphical login managers do not list them.
11112 @anchor{user-account-password}
11113 @cindex password, for user accounts
11114 @item @code{password} (default: @code{#f})
11115 You would normally leave this field to @code{#f}, initialize user
11116 passwords as @code{root} with the @command{passwd} command, and then let
11117 users change it with @command{passwd}. Passwords set with
11118 @command{passwd} are of course preserved across reboot and
11121 If you @emph{do} want to set an initial password for an account, then
11122 this field must contain the encrypted password, as a string. You can use the
11123 @code{crypt} procedure for this purpose:
11130 ;; Specify a SHA-512-hashed initial password.
11131 (password (crypt "InitialPassword!" "$6$abc")))
11135 The hash of this initial password will be available in a file in
11136 @file{/gnu/store}, readable by all the users, so this method must be used with
11140 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11141 more information on password encryption, and @ref{Encryption,,, guile, GNU
11142 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11148 User group declarations are even simpler:
11151 (user-group (name "students"))
11154 @deftp {Data Type} user-group
11155 This type is for, well, user groups. There are just a few fields:
11159 The name of the group.
11161 @item @code{id} (default: @code{#f})
11162 The group identifier (a number). If @code{#f}, a new number is
11163 automatically allocated when the group is created.
11165 @item @code{system?} (default: @code{#f})
11166 This Boolean value indicates whether the group is a ``system'' group.
11167 System groups have low numerical IDs.
11169 @item @code{password} (default: @code{#f})
11170 What, user groups can have a password? Well, apparently yes. Unless
11171 @code{#f}, this field specifies the password of the group.
11176 For convenience, a variable lists all the basic user groups one may
11179 @defvr {Scheme Variable} %base-groups
11180 This is the list of basic user groups that users and/or packages expect
11181 to be present on the system. This includes groups such as ``root'',
11182 ``wheel'', and ``users'', as well as groups used to control access to
11183 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11186 @defvr {Scheme Variable} %base-user-accounts
11187 This is the list of basic system accounts that programs may expect to
11188 find on a GNU/Linux system, such as the ``nobody'' account.
11190 Note that the ``root'' account is not included here. It is a
11191 special-case and is automatically added whether or not it is specified.
11194 @node Keyboard Layout
11195 @section Keyboard Layout
11197 @cindex keyboard layout
11199 To specify what each key of your keyboard does, you need to tell the operating
11200 system what @dfn{keyboard layout} you want to use. The default, when nothing
11201 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11202 However, German speakers will usually prefer the German QWERTZ layout, French
11203 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11204 or bépo, and they might even want to further customize the effect of some of
11205 the keys. This section explains how to get that done.
11207 @cindex keyboard layout, definition
11208 There are three components that will want to know about your keyboard layout:
11212 The @emph{bootloader} may want to know what keyboard layout you want to use
11213 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11214 you want, for instance, to make sure that you can type the passphrase of your
11215 encrypted root partition using the right layout.
11218 The @emph{operating system kernel}, Linux, will need that so that the console
11219 is properly configured (@pxref{operating-system Reference,
11220 @code{keyboard-layout}}).
11223 The @emph{graphical display server}, usually Xorg, also has its own idea of
11224 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11227 Guix allows you to configure all three separately but, fortunately, it allows
11228 you to share the same keyboard layout for all three components.
11230 @cindex XKB, keyboard layouts
11231 Keyboard layouts are represented by records created by the
11232 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11233 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11234 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11235 optional variant name, an optional keyboard model name, and a possibly empty
11236 list of additional options. In most cases the layout name is all you care
11237 about. Here are a few example:
11240 ;; The German QWERTZ layout. Here we assume a standard
11241 ;; "pc105" keyboard model.
11242 (keyboard-layout "de")
11244 ;; The bépo variant of the French layout.
11245 (keyboard-layout "fr" "bepo")
11247 ;; The Catalan layout.
11248 (keyboard-layout "es" "cat")
11250 ;; The Latin American Spanish layout. In addition, the
11251 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11252 ;; and the "Menu" key is used as a "Compose" key to enter
11253 ;; accented letters.
11254 (keyboard-layout "latam"
11255 #:options '("ctrl:nocaps" "compose:menu"))
11257 ;; The Russian layout for a ThinkPad keyboard.
11258 (keyboard-layout "ru" #:model "thinkpad")
11260 ;; The "US international" layout, which is the US layout plus
11261 ;; dead keys to enter accented characters. This is for an
11262 ;; Apple MacBook keyboard.
11263 (keyboard-layout "us" "intl" #:model "macbook78")
11266 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11267 for a complete list of supported layouts, variants, and models.
11269 @cindex keyboard layout, configuration
11270 Let's say you want your system to use the Turkish keyboard layout throughout
11271 your system---bootloader, console, and Xorg. Here's what your system
11272 configuration would look like:
11274 @findex set-xorg-configuration
11276 ;; Using the Turkish layout for the bootloader, the console,
11281 (keyboard-layout (keyboard-layout "tr")) ;for the console
11282 (bootloader (bootloader-configuration
11283 (bootloader grub-efi-bootloader)
11284 (target "/boot/efi")
11285 (keyboard-layout keyboard-layout))) ;for GRUB
11286 (services (cons (set-xorg-configuration
11287 (xorg-configuration ;for Xorg
11288 (keyboard-layout keyboard-layout)))
11289 %desktop-services)))
11292 In the example above, for GRUB and for Xorg, we just refer to the
11293 @code{keyboard-layout} field defined above, but we could just as well refer to
11294 a different layout. The @code{set-xorg-configuration} procedure communicates
11295 the desired Xorg configuration to the graphical log-in manager, by default
11298 We've discussed how to specify the @emph{default} keyboard layout of your
11299 system when it starts, but you can also adjust it at run time:
11303 If you're using GNOME, its settings panel has a ``Region & Language'' entry
11304 where you can select one or more keyboard layouts.
11307 Under Xorg, the @command{setxkbmap} command (from the same-named package)
11308 allows you to change the current layout. For example, this is how you would
11309 change the layout to US Dvorak:
11312 setxkbmap us dvorak
11316 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
11317 console. However, note that @code{loadkeys} does @emph{not} use the XKB
11318 keyboard layout categorization described above. The command below loads the
11319 French bépo layout:
11330 A @dfn{locale} defines cultural conventions for a particular language
11331 and region of the world (@pxref{Locales,,, libc, The GNU C Library
11332 Reference Manual}). Each locale has a name that typically has the form
11333 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
11334 @code{fr_LU.utf8} designates the locale for the French language, with
11335 cultural conventions from Luxembourg, and using the UTF-8 encoding.
11337 @cindex locale definition
11338 Usually, you will want to specify the default locale for the machine
11339 using the @code{locale} field of the @code{operating-system} declaration
11340 (@pxref{operating-system Reference, @code{locale}}).
11342 The selected locale is automatically added to the @dfn{locale
11343 definitions} known to the system if needed, with its codeset inferred
11344 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
11345 @code{UTF-8} codeset. Additional locale definitions can be specified in
11346 the @code{locale-definitions} slot of @code{operating-system}---this is
11347 useful, for instance, if the codeset could not be inferred from the
11348 locale name. The default set of locale definitions includes some widely
11349 used locales, but not all the available locales, in order to save space.
11351 For instance, to add the North Frisian locale for Germany, the value of
11355 (cons (locale-definition
11356 (name "fy_DE.utf8") (source "fy_DE"))
11357 %default-locale-definitions)
11360 Likewise, to save space, one might want @code{locale-definitions} to
11361 list only the locales that are actually used, as in:
11364 (list (locale-definition
11365 (name "ja_JP.eucjp") (source "ja_JP")
11366 (charset "EUC-JP")))
11370 The compiled locale definitions are available at
11371 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
11372 version, which is the default location where the GNU@tie{}libc provided
11373 by Guix looks for locale data. This can be overridden using the
11374 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
11375 @code{LOCPATH} and locale packages}).
11377 The @code{locale-definition} form is provided by the @code{(gnu system
11378 locale)} module. Details are given below.
11380 @deftp {Data Type} locale-definition
11381 This is the data type of a locale definition.
11386 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
11387 Reference Manual}, for more information on locale names.
11389 @item @code{source}
11390 The name of the source for that locale. This is typically the
11391 @code{@var{language}_@var{territory}} part of the locale name.
11393 @item @code{charset} (default: @code{"UTF-8"})
11394 The ``character set'' or ``code set'' for that locale,
11395 @uref{https://www.iana.org/assignments/character-sets, as defined by
11401 @defvr {Scheme Variable} %default-locale-definitions
11402 A list of commonly used UTF-8 locales, used as the default
11403 value of the @code{locale-definitions} field of @code{operating-system}
11406 @cindex locale name
11407 @cindex normalized codeset in locale names
11408 These locale definitions use the @dfn{normalized codeset} for the part
11409 that follows the dot in the name (@pxref{Using gettextized software,
11410 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
11411 instance it has @code{uk_UA.utf8} but @emph{not}, say,
11412 @code{uk_UA.UTF-8}.
11415 @subsection Locale Data Compatibility Considerations
11417 @cindex incompatibility, of locale data
11418 @code{operating-system} declarations provide a @code{locale-libcs} field
11419 to specify the GNU@tie{}libc packages that are used to compile locale
11420 declarations (@pxref{operating-system Reference}). ``Why would I
11421 care?'', you may ask. Well, it turns out that the binary format of
11422 locale data is occasionally incompatible from one libc version to
11425 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
11426 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
11427 For instance, a program linked against libc version 2.21 is unable to
11428 read locale data produced with libc 2.22; worse, that program
11429 @emph{aborts} instead of simply ignoring the incompatible locale
11430 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
11431 the incompatible locale data, which is already an improvement.}.
11432 Similarly, a program linked against libc 2.22 can read most, but not
11433 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
11434 data is incompatible); thus calls to @code{setlocale} may fail, but
11435 programs will not abort.
11437 The ``problem'' with Guix is that users have a lot of freedom: They can
11438 choose whether and when to upgrade software in their profiles, and might
11439 be using a libc version different from the one the system administrator
11440 used to build the system-wide locale data.
11442 Fortunately, unprivileged users can also install their own locale data
11443 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
11444 @code{GUIX_LOCPATH} and locale packages}).
11446 Still, it is best if the system-wide locale data at
11447 @file{/run/current-system/locale} is built for all the libc versions
11448 actually in use on the system, so that all the programs can access
11449 it---this is especially crucial on a multi-user system. To do that, the
11450 administrator can specify several libc packages in the
11451 @code{locale-libcs} field of @code{operating-system}:
11454 (use-package-modules base)
11458 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
11461 This example would lead to a system containing locale definitions for
11462 both libc 2.21 and the current version of libc in
11463 @file{/run/current-system/locale}.
11469 @cindex system services
11470 An important part of preparing an @code{operating-system} declaration is
11471 listing @dfn{system services} and their configuration (@pxref{Using the
11472 Configuration System}). System services are typically daemons launched
11473 when the system boots, or other actions needed at that time---e.g.,
11474 configuring network access.
11476 Guix has a broad definition of ``service'' (@pxref{Service
11477 Composition}), but many services are managed by the GNU@tie{}Shepherd
11478 (@pxref{Shepherd Services}). On a running system, the @command{herd}
11479 command allows you to list the available services, show their status,
11480 start and stop them, or do other specific operations (@pxref{Jump
11481 Start,,, shepherd, The GNU Shepherd Manual}). For example:
11487 The above command, run as @code{root}, lists the currently defined
11488 services. The @command{herd doc} command shows a synopsis of the given
11489 service and its associated actions:
11493 Run libc's name service cache daemon (nscd).
11495 # herd doc nscd action invalidate
11496 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
11499 The @command{start}, @command{stop}, and @command{restart} sub-commands
11500 have the effect you would expect. For instance, the commands below stop
11501 the nscd service and restart the Xorg display server:
11505 Service nscd has been stopped.
11506 # herd restart xorg-server
11507 Service xorg-server has been stopped.
11508 Service xorg-server has been started.
11511 The following sections document the available services, starting with
11512 the core services, that may be used in an @code{operating-system}
11516 * Base Services:: Essential system services.
11517 * Scheduled Job Execution:: The mcron service.
11518 * Log Rotation:: The rottlog service.
11519 * Networking Services:: Network setup, SSH daemon, etc.
11520 * X Window:: Graphical display.
11521 * Printing Services:: Local and remote printer support.
11522 * Desktop Services:: D-Bus and desktop services.
11523 * Sound Services:: ALSA and Pulseaudio services.
11524 * Database Services:: SQL databases, key-value stores, etc.
11525 * Mail Services:: IMAP, POP3, SMTP, and all that.
11526 * Messaging Services:: Messaging services.
11527 * Telephony Services:: Telephony services.
11528 * Monitoring Services:: Monitoring services.
11529 * Kerberos Services:: Kerberos services.
11530 * LDAP Services:: LDAP services.
11531 * Web Services:: Web servers.
11532 * Certificate Services:: TLS certificates via Let's Encrypt.
11533 * DNS Services:: DNS daemons.
11534 * VPN Services:: VPN daemons.
11535 * Network File System:: NFS related services.
11536 * Continuous Integration:: The Cuirass service.
11537 * Power Management Services:: Extending battery life.
11538 * Audio Services:: The MPD.
11539 * Virtualization Services:: Virtualization services.
11540 * Version Control Services:: Providing remote access to Git repositories.
11541 * Game Services:: Game servers.
11542 * Miscellaneous Services:: Other services.
11545 @node Base Services
11546 @subsection Base Services
11548 The @code{(gnu services base)} module provides definitions for the basic
11549 services that one expects from the system. The services exported by
11550 this module are listed below.
11552 @defvr {Scheme Variable} %base-services
11553 This variable contains a list of basic services (@pxref{Service Types
11554 and Services}, for more information on service objects) one would
11555 expect from the system: a login service (mingetty) on each tty, syslogd,
11556 the libc name service cache daemon (nscd), the udev device manager, and
11559 This is the default value of the @code{services} field of
11560 @code{operating-system} declarations. Usually, when customizing a
11561 system, you will want to append services to @code{%base-services}, like
11565 (append (list (service avahi-service-type)
11566 (service openssh-service-type))
11571 @defvr {Scheme Variable} special-files-service-type
11572 This is the service that sets up ``special files'' such as
11573 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
11575 The value associated with @code{special-files-service-type} services
11576 must be a list of tuples where the first element is the ``special file''
11577 and the second element is its target. By default it is:
11579 @cindex @file{/bin/sh}
11580 @cindex @file{sh}, in @file{/bin}
11582 `(("/bin/sh" ,(file-append @var{bash} "/bin/sh")))
11585 @cindex @file{/usr/bin/env}
11586 @cindex @file{env}, in @file{/usr/bin}
11587 If you want to add, say, @code{/usr/bin/env} to your system, you can
11591 `(("/bin/sh" ,(file-append @var{bash} "/bin/sh"))
11592 ("/usr/bin/env" ,(file-append @var{coreutils} "/bin/env")))
11595 Since this is part of @code{%base-services}, you can use
11596 @code{modify-services} to customize the set of special files
11597 (@pxref{Service Reference, @code{modify-services}}). But the simple way
11598 to add a special file is @i{via} the @code{extra-special-file} procedure
11602 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
11603 Use @var{target} as the ``special file'' @var{file}.
11605 For example, adding the following lines to the @code{services} field of
11606 your operating system declaration leads to a @file{/usr/bin/env}
11610 (extra-special-file "/usr/bin/env"
11611 (file-append coreutils "/bin/env"))
11615 @deffn {Scheme Procedure} host-name-service @var{name}
11616 Return a service that sets the host name to @var{name}.
11619 @deffn {Scheme Procedure} login-service @var{config}
11620 Return a service to run login according to @var{config}, a
11621 @code{<login-configuration>} object, which specifies the message of the day,
11622 among other things.
11625 @deftp {Data Type} login-configuration
11626 This is the data type representing the configuration of login.
11631 @cindex message of the day
11632 A file-like object containing the ``message of the day''.
11634 @item @code{allow-empty-passwords?} (default: @code{#t})
11635 Allow empty passwords by default so that first-time users can log in when
11636 the 'root' account has just been created.
11641 @deffn {Scheme Procedure} mingetty-service @var{config}
11642 Return a service to run mingetty according to @var{config}, a
11643 @code{<mingetty-configuration>} object, which specifies the tty to run, among
11647 @deftp {Data Type} mingetty-configuration
11648 This is the data type representing the configuration of Mingetty, which
11649 provides the default implementation of virtual console log-in.
11654 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
11656 @item @code{auto-login} (default: @code{#f})
11657 When true, this field must be a string denoting the user name under
11658 which the system automatically logs in. When it is @code{#f}, a
11659 user name and password must be entered to log in.
11661 @item @code{login-program} (default: @code{#f})
11662 This must be either @code{#f}, in which case the default log-in program
11663 is used (@command{login} from the Shadow tool suite), or a gexp denoting
11664 the name of the log-in program.
11666 @item @code{login-pause?} (default: @code{#f})
11667 When set to @code{#t} in conjunction with @var{auto-login}, the user
11668 will have to press a key before the log-in shell is launched.
11670 @item @code{mingetty} (default: @var{mingetty})
11671 The Mingetty package to use.
11676 @deffn {Scheme Procedure} agetty-service @var{config}
11677 Return a service to run agetty according to @var{config}, an
11678 @code{<agetty-configuration>} object, which specifies the tty to run,
11679 among other things.
11682 @deftp {Data Type} agetty-configuration
11683 This is the data type representing the configuration of agetty, which
11684 implements virtual and serial console log-in. See the @code{agetty(8)}
11685 man page for more information.
11690 The name of the console this agetty runs on, as a string---e.g.,
11691 @code{"ttyS0"}. This argument is optional, it will default to
11692 a reasonable default serial port used by the kernel Linux.
11694 For this, if there is a value for an option @code{agetty.tty} in the kernel
11695 command line, agetty will extract the device name of the serial port
11696 from it and use that.
11698 If not and if there is a value for an option @code{console} with a tty in
11699 the Linux command line, agetty will extract the device name of the
11700 serial port from it and use that.
11702 In both cases, agetty will leave the other serial device settings
11703 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
11706 @item @code{baud-rate} (default: @code{#f})
11707 A string containing a comma-separated list of one or more baud rates, in
11710 @item @code{term} (default: @code{#f})
11711 A string containing the value used for the @code{TERM} environment
11714 @item @code{eight-bits?} (default: @code{#f})
11715 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
11718 @item @code{auto-login} (default: @code{#f})
11719 When passed a login name, as a string, the specified user will be logged
11720 in automatically without prompting for their login name or password.
11722 @item @code{no-reset?} (default: @code{#f})
11723 When @code{#t}, don't reset terminal cflags (control modes).
11725 @item @code{host} (default: @code{#f})
11726 This accepts a string containing the "login_host", which will be written
11727 into the @file{/var/run/utmpx} file.
11729 @item @code{remote?} (default: @code{#f})
11730 When set to @code{#t} in conjunction with @var{host}, this will add an
11731 @code{-r} fakehost option to the command line of the login program
11732 specified in @var{login-program}.
11734 @item @code{flow-control?} (default: @code{#f})
11735 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
11737 @item @code{no-issue?} (default: @code{#f})
11738 When set to @code{#t}, the contents of the @file{/etc/issue} file will
11739 not be displayed before presenting the login prompt.
11741 @item @code{init-string} (default: @code{#f})
11742 This accepts a string that will be sent to the tty or modem before
11743 sending anything else. It can be used to initialize a modem.
11745 @item @code{no-clear?} (default: @code{#f})
11746 When set to @code{#t}, agetty will not clear the screen before showing
11749 @item @code{login-program} (default: (file-append shadow "/bin/login"))
11750 This must be either a gexp denoting the name of a log-in program, or
11751 unset, in which case the default value is the @command{login} from the
11754 @item @code{local-line} (default: @code{#f})
11755 Control the CLOCAL line flag. This accepts one of three symbols as
11756 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
11757 the default value chosen by agetty is @code{'auto}.
11759 @item @code{extract-baud?} (default: @code{#f})
11760 When set to @code{#t}, instruct agetty to try to extract the baud rate
11761 from the status messages produced by certain types of modems.
11763 @item @code{skip-login?} (default: @code{#f})
11764 When set to @code{#t}, do not prompt the user for a login name. This
11765 can be used with @var{login-program} field to use non-standard login
11768 @item @code{no-newline?} (default: @code{#f})
11769 When set to @code{#t}, do not print a newline before printing the
11770 @file{/etc/issue} file.
11772 @c Is this dangerous only when used with login-program, or always?
11773 @item @code{login-options} (default: @code{#f})
11774 This option accepts a string containing options that are passed to the
11775 login program. When used with the @var{login-program}, be aware that a
11776 malicious user could try to enter a login name containing embedded
11777 options that could be parsed by the login program.
11779 @item @code{login-pause} (default: @code{#f})
11780 When set to @code{#t}, wait for any key before showing the login prompt.
11781 This can be used in conjunction with @var{auto-login} to save memory by
11782 lazily spawning shells.
11784 @item @code{chroot} (default: @code{#f})
11785 Change root to the specified directory. This option accepts a directory
11788 @item @code{hangup?} (default: @code{#f})
11789 Use the Linux system call @code{vhangup} to do a virtual hangup of the
11790 specified terminal.
11792 @item @code{keep-baud?} (default: @code{#f})
11793 When set to @code{#t}, try to keep the existing baud rate. The baud
11794 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
11797 @item @code{timeout} (default: @code{#f})
11798 When set to an integer value, terminate if no user name could be read
11799 within @var{timeout} seconds.
11801 @item @code{detect-case?} (default: @code{#f})
11802 When set to @code{#t}, turn on support for detecting an uppercase-only
11803 terminal. This setting will detect a login name containing only
11804 uppercase letters as indicating an uppercase-only terminal and turn on
11805 some upper-to-lower case conversions. Note that this will not support
11806 Unicode characters.
11808 @item @code{wait-cr?} (default: @code{#f})
11809 When set to @code{#t}, wait for the user or modem to send a
11810 carriage-return or linefeed character before displaying
11811 @file{/etc/issue} or login prompt. This is typically used with the
11812 @var{init-string} option.
11814 @item @code{no-hints?} (default: @code{#f})
11815 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
11818 @item @code{no-hostname?} (default: @code{#f})
11819 By default, the hostname is printed. When this option is set to
11820 @code{#t}, no hostname will be shown at all.
11822 @item @code{long-hostname?} (default: @code{#f})
11823 By default, the hostname is only printed until the first dot. When this
11824 option is set to @code{#t}, the fully qualified hostname by
11825 @code{gethostname} or @code{getaddrinfo} is shown.
11827 @item @code{erase-characters} (default: @code{#f})
11828 This option accepts a string of additional characters that should be
11829 interpreted as backspace when the user types their login name.
11831 @item @code{kill-characters} (default: @code{#f})
11832 This option accepts a string that should be interpreted to mean "ignore
11833 all previous characters" (also called a "kill" character) when the user
11834 types their login name.
11836 @item @code{chdir} (default: @code{#f})
11837 This option accepts, as a string, a directory path that will be changed
11840 @item @code{delay} (default: @code{#f})
11841 This options accepts, as an integer, the number of seconds to sleep
11842 before opening the tty and displaying the login prompt.
11844 @item @code{nice} (default: @code{#f})
11845 This option accepts, as an integer, the nice value with which to run the
11846 @command{login} program.
11848 @item @code{extra-options} (default: @code{'()})
11849 This option provides an "escape hatch" for the user to provide arbitrary
11850 command-line arguments to @command{agetty} as a list of strings.
11855 @deffn {Scheme Procedure} kmscon-service-type @var{config}
11856 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
11857 according to @var{config}, a @code{<kmscon-configuration>} object, which
11858 specifies the tty to run, among other things.
11861 @deftp {Data Type} kmscon-configuration
11862 This is the data type representing the configuration of Kmscon, which
11863 implements virtual console log-in.
11867 @item @code{virtual-terminal}
11868 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
11870 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
11871 A gexp denoting the name of the log-in program. The default log-in program is
11872 @command{login} from the Shadow tool suite.
11874 @item @code{login-arguments} (default: @code{'("-p")})
11875 A list of arguments to pass to @command{login}.
11877 @item @code{auto-login} (default: @code{#f})
11878 When passed a login name, as a string, the specified user will be logged
11879 in automatically without prompting for their login name or password.
11881 @item @code{hardware-acceleration?} (default: #f)
11882 Whether to use hardware acceleration.
11884 @item @code{kmscon} (default: @var{kmscon})
11885 The Kmscon package to use.
11890 @cindex name service cache daemon
11892 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
11893 [#:name-services '()]
11894 Return a service that runs the libc name service cache daemon (nscd) with the
11895 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
11896 Service Switch}, for an example.
11898 For convenience, the Shepherd service for nscd provides the following actions:
11902 @cindex cache invalidation, nscd
11903 @cindex nscd, cache invalidation
11904 This invalidate the given cache. For instance, running:
11907 herd invalidate nscd hosts
11911 invalidates the host name lookup cache of nscd.
11914 Running @command{herd statistics nscd} displays information about nscd usage
11920 @defvr {Scheme Variable} %nscd-default-configuration
11921 This is the default @code{<nscd-configuration>} value (see below) used
11922 by @code{nscd-service}. It uses the caches defined by
11923 @var{%nscd-default-caches}; see below.
11926 @deftp {Data Type} nscd-configuration
11927 This is the data type representing the name service cache daemon (nscd)
11932 @item @code{name-services} (default: @code{'()})
11933 List of packages denoting @dfn{name services} that must be visible to
11934 the nscd---e.g., @code{(list @var{nss-mdns})}.
11936 @item @code{glibc} (default: @var{glibc})
11937 Package object denoting the GNU C Library providing the @command{nscd}
11940 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
11941 Name of the nscd log file. This is where debugging output goes when
11942 @code{debug-level} is strictly positive.
11944 @item @code{debug-level} (default: @code{0})
11945 Integer denoting the debugging levels. Higher numbers mean that more
11946 debugging output is logged.
11948 @item @code{caches} (default: @var{%nscd-default-caches})
11949 List of @code{<nscd-cache>} objects denoting things to be cached; see
11955 @deftp {Data Type} nscd-cache
11956 Data type representing a cache database of nscd and its parameters.
11960 @item @code{database}
11961 This is a symbol representing the name of the database to be cached.
11962 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
11963 @code{services}, which designate the corresponding NSS database
11964 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
11966 @item @code{positive-time-to-live}
11967 @itemx @code{negative-time-to-live} (default: @code{20})
11968 A number representing the number of seconds during which a positive or
11969 negative lookup result remains in cache.
11971 @item @code{check-files?} (default: @code{#t})
11972 Whether to check for updates of the files corresponding to
11975 For instance, when @var{database} is @code{hosts}, setting this flag
11976 instructs nscd to check for updates in @file{/etc/hosts} and to take
11979 @item @code{persistent?} (default: @code{#t})
11980 Whether the cache should be stored persistently on disk.
11982 @item @code{shared?} (default: @code{#t})
11983 Whether the cache should be shared among users.
11985 @item @code{max-database-size} (default: 32@tie{}MiB)
11986 Maximum size in bytes of the database cache.
11988 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
11989 @c settings, so leave them out.
11994 @defvr {Scheme Variable} %nscd-default-caches
11995 List of @code{<nscd-cache>} objects used by default by
11996 @code{nscd-configuration} (see above).
11998 It enables persistent and aggressive caching of service and host name
11999 lookups. The latter provides better host name lookup performance,
12000 resilience in the face of unreliable name servers, and also better
12001 privacy---often the result of host name lookups is in local cache, so
12002 external name servers do not even need to be queried.
12005 @anchor{syslog-configuration-type}
12008 @deftp {Data Type} syslog-configuration
12009 This data type represents the configuration of the syslog daemon.
12012 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12013 The syslog daemon to use.
12015 @item @code{config-file} (default: @code{%default-syslog.conf})
12016 The syslog configuration file to use.
12021 @anchor{syslog-service}
12023 @deffn {Scheme Procedure} syslog-service @var{config}
12024 Return a service that runs a syslog daemon according to @var{config}.
12026 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12027 information on the configuration file syntax.
12030 @defvr {Scheme Variable} guix-service-type
12031 This is the type of the service that runs the build daemon,
12032 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12033 @code{guix-configuration} record as described below.
12036 @anchor{guix-configuration-type}
12037 @deftp {Data Type} guix-configuration
12038 This data type represents the configuration of the Guix build daemon.
12039 @xref{Invoking guix-daemon}, for more information.
12042 @item @code{guix} (default: @var{guix})
12043 The Guix package to use.
12045 @item @code{build-group} (default: @code{"guixbuild"})
12046 Name of the group for build user accounts.
12048 @item @code{build-accounts} (default: @code{10})
12049 Number of build user accounts to create.
12051 @item @code{authorize-key?} (default: @code{#t})
12052 @cindex substitutes, authorization thereof
12053 Whether to authorize the substitute keys listed in
12054 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12055 (@pxref{Substitutes}).
12057 @vindex %default-authorized-guix-keys
12058 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12059 The list of authorized key files for archive imports, as a list of
12060 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12061 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12063 @item @code{use-substitutes?} (default: @code{#t})
12064 Whether to use substitutes.
12066 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12067 The list of URLs where to look for substitutes by default.
12069 @item @code{max-silent-time} (default: @code{0})
12070 @itemx @code{timeout} (default: @code{0})
12071 The number of seconds of silence and the number of seconds of activity,
12072 respectively, after which a build process times out. A value of zero
12073 disables the timeout.
12075 @item @code{log-compression} (default: @code{'bzip2})
12076 The type of compression used for build logs---one of @code{gzip},
12077 @code{bzip2}, or @code{none}.
12079 @item @code{extra-options} (default: @code{'()})
12080 List of extra command-line options for @command{guix-daemon}.
12082 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12083 File where @command{guix-daemon}'s standard output and standard error
12086 @item @code{http-proxy} (default: @code{#f})
12087 The HTTP proxy used for downloading fixed-output derivations and
12090 @item @code{tmpdir} (default: @code{#f})
12091 A directory path where the @command{guix-daemon} will perform builds.
12096 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12097 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12098 udev rules can be provided as a list of files through the @var{rules}
12099 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12100 @code{(gnu services base)} simplify the creation of such rule files.
12103 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12104 Return a udev-rule file named @var{file-name} containing the rules
12105 defined by the @var{contents} literal.
12107 In the following example, a rule for a USB device is defined to be
12108 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12109 upon detecting a USB device with a given product identifier.
12112 (define %example-udev-rule
12114 "90-usb-thing.rules"
12115 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12116 "ATTR@{product@}==\"Example\", "
12117 "RUN+=\"/path/to/script\"")))
12120 The @command{herd rules udev} command, as root, returns the name of the
12121 directory containing all the active udev rules.
12124 Here we show how the default @var{udev-service} can be extended with it.
12130 (modify-services %desktop-services
12131 (udev-service-type config =>
12132 (udev-configuration (inherit config)
12133 (rules (append (udev-configuration-rules config)
12134 (list %example-udev-rule))))))))
12137 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12138 Return a udev file named @var{file-name} containing the rules defined
12139 within @var{file}, a file-like object.
12141 The following example showcases how we can use an existing rule file.
12144 (use-modules (guix download) ;for url-fetch
12145 (guix packages) ;for origin
12148 (define %android-udev-rules
12150 "51-android-udev.rules"
12151 (let ((version "20170910"))
12154 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12155 "android-udev-rules/" version "/51-android.rules"))
12157 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12161 Additionally, Guix package definitions can be included in @var{rules} in
12162 order to extend the udev rules with the definitions found under their
12163 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12164 @var{file->udev-rule} example, we could have used the
12165 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12166 packages android)} module.
12168 The following example shows how to use the @var{android-udev-rules}
12169 package so that the Android tool @command{adb} can detect devices
12170 without root privileges. It also details how to create the
12171 @code{adbusers} group, which is required for the proper functioning of
12172 the rules defined within the @var{android-udev-rules} package. To
12173 create such a group, we must define it both as part of the
12174 @var{supplementary-groups} of our @var{user-account} declaration, as
12175 well as in the @var{groups} field of the @var{operating-system} record.
12178 (use-modules (gnu packages android) ;for android-udev-rules
12179 (gnu system shadow) ;for user-group
12184 (users (cons (user-acount
12186 (supplementary-groups
12187 '("adbusers" ;for adb
12188 "wheel" "netdev" "audio" "video"))
12191 (groups (cons (user-group (system? #t) (name "adbusers"))
12197 (modify-services %desktop-services
12200 (udev-configuration (inherit config)
12201 (rules (cons android-udev-rules
12202 (udev-configuration-rules config))))))))
12205 @defvr {Scheme Variable} urandom-seed-service-type
12206 Save some entropy in @var{%random-seed-file} to seed @file{/dev/urandom}
12207 when rebooting. It also tries to seed @file{/dev/urandom} from
12208 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12212 @defvr {Scheme Variable} %random-seed-file
12213 This is the name of the file where some random bytes are saved by
12214 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12215 It defaults to @file{/var/lib/random-seed}.
12220 @defvr {Scheme Variable} gpm-service-type
12221 This is the type of the service that runs GPM, the @dfn{general-purpose
12222 mouse daemon}, which provides mouse support to the Linux console. GPM
12223 allows users to use the mouse in the console, notably to select, copy,
12226 The value for services of this type must be a @code{gpm-configuration}
12227 (see below). This service is not part of @code{%base-services}.
12230 @deftp {Data Type} gpm-configuration
12231 Data type representing the configuration of GPM.
12234 @item @code{options} (default: @code{%default-gpm-options})
12235 Command-line options passed to @command{gpm}. The default set of
12236 options instruct @command{gpm} to listen to mouse events on
12237 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12240 @item @code{gpm} (default: @code{gpm})
12241 The GPM package to use.
12246 @anchor{guix-publish-service-type}
12247 @deffn {Scheme Variable} guix-publish-service-type
12248 This is the service type for @command{guix publish} (@pxref{Invoking
12249 guix publish}). Its value must be a @code{guix-publish-configuration}
12250 object, as described below.
12252 This assumes that @file{/etc/guix} already contains a signing key pair as
12253 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12254 archive}). If that is not the case, the service will fail to start.
12257 @deftp {Data Type} guix-publish-configuration
12258 Data type representing the configuration of the @code{guix publish}
12262 @item @code{guix} (default: @code{guix})
12263 The Guix package to use.
12265 @item @code{port} (default: @code{80})
12266 The TCP port to listen for connections.
12268 @item @code{host} (default: @code{"localhost"})
12269 The host (and thus, network interface) to listen to. Use
12270 @code{"0.0.0.0"} to listen on all the network interfaces.
12272 @item @code{compression} (default: @code{'(("gzip" 3))})
12273 This is a list of compression method/level tuple used when compressing
12274 substitutes. For example, to compress all substitutes with @emph{both} lzip
12275 at level 7 and gzip at level 9, write:
12278 '(("lzip" 7) ("gzip" 9))
12281 Level 9 achieves the best compression ratio at the expense of increased CPU
12282 usage, whereas level 1 achieves fast compression.
12284 An empty list disables compression altogether.
12286 @item @code{nar-path} (default: @code{"nar"})
12287 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
12288 publish, @code{--nar-path}}, for details.
12290 @item @code{cache} (default: @code{#f})
12291 When it is @code{#f}, disable caching and instead generate archives on
12292 demand. Otherwise, this should be the name of a directory---e.g.,
12293 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
12294 archives and meta-data ready to be sent. @xref{Invoking guix publish,
12295 @option{--cache}}, for more information on the tradeoffs involved.
12297 @item @code{workers} (default: @code{#f})
12298 When it is an integer, this is the number of worker threads used for
12299 caching; when @code{#f}, the number of processors is used.
12300 @xref{Invoking guix publish, @option{--workers}}, for more information.
12302 @item @code{ttl} (default: @code{#f})
12303 When it is an integer, this denotes the @dfn{time-to-live} in seconds
12304 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
12305 for more information.
12309 @anchor{rngd-service}
12310 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
12311 [#:device "/dev/hwrng"]
12312 Return a service that runs the @command{rngd} program from @var{rng-tools}
12313 to add @var{device} to the kernel's entropy pool. The service will fail if
12314 @var{device} does not exist.
12317 @anchor{pam-limits-service}
12318 @cindex session limits
12323 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
12325 Return a service that installs a configuration file for the
12326 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
12327 @code{pam_limits} module}. The procedure optionally takes a list of
12328 @code{pam-limits-entry} values, which can be used to specify
12329 @code{ulimit} limits and nice priority limits to user sessions.
12331 The following limits definition sets two hard and soft limits for all
12332 login sessions of users in the @code{realtime} group:
12335 (pam-limits-service
12337 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
12338 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
12341 The first entry increases the maximum realtime priority for
12342 non-privileged processes; the second entry lifts any restriction of the
12343 maximum address space that can be locked in memory. These settings are
12344 commonly used for real-time audio systems.
12347 @node Scheduled Job Execution
12348 @subsection Scheduled Job Execution
12352 @cindex scheduling jobs
12353 The @code{(gnu services mcron)} module provides an interface to
12354 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
12355 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
12356 Unix @command{cron} daemon; the main difference is that it is
12357 implemented in Guile Scheme, which provides a lot of flexibility when
12358 specifying the scheduling of jobs and their actions.
12360 The example below defines an operating system that runs the
12361 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
12362 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
12363 well as the @command{mkid} command on behalf of an unprivileged user
12364 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
12365 gexps to introduce job definitions that are passed to mcron
12366 (@pxref{G-Expressions}).
12369 (use-modules (guix) (gnu) (gnu services mcron))
12370 (use-package-modules base idutils)
12372 (define updatedb-job
12373 ;; Run 'updatedb' at 3AM every day. Here we write the
12374 ;; job's action as a Scheme procedure.
12375 #~(job '(next-hour '(3))
12377 (execl (string-append #$findutils "/bin/updatedb")
12379 "--prunepaths=/tmp /var/tmp /gnu/store"))))
12381 (define garbage-collector-job
12382 ;; Collect garbage 5 minutes after midnight every day.
12383 ;; The job's action is a shell command.
12384 #~(job "5 0 * * *" ;Vixie cron syntax
12387 (define idutils-job
12388 ;; Update the index database as user "charlie" at 12:15PM
12389 ;; and 19:15PM. This runs from the user's home directory.
12390 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
12391 (string-append #$idutils "/bin/mkid src")
12396 (services (cons (service mcron-service-type
12397 (mcron-configuration
12398 (jobs (list garbage-collector-job
12404 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
12405 for more information on mcron job specifications. Below is the
12406 reference of the mcron service.
12408 On a running system, you can use the @code{schedule} action of the service to
12409 visualize the mcron jobs that will be executed next:
12412 # herd schedule mcron
12416 The example above lists the next five tasks that will be executed, but you can
12417 also specify the number of tasks to display:
12420 # herd schedule mcron 10
12423 @defvr {Scheme Variable} mcron-service-type
12424 This is the type of the @code{mcron} service, whose value is an
12425 @code{mcron-configuration} object.
12427 This service type can be the target of a service extension that provides
12428 it additional job specifications (@pxref{Service Composition}). In
12429 other words, it is possible to define services that provide additional
12433 @deftp {Data Type} mcron-configuration
12434 Data type representing the configuration of mcron.
12437 @item @code{mcron} (default: @var{mcron})
12438 The mcron package to use.
12441 This is a list of gexps (@pxref{G-Expressions}), where each gexp
12442 corresponds to an mcron job specification (@pxref{Syntax, mcron job
12443 specifications,, mcron, GNU@tie{}mcron}).
12449 @subsection Log Rotation
12452 @cindex log rotation
12454 Log files such as those found in @file{/var/log} tend to grow endlessly,
12455 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
12456 their contents in separate files, possibly compressed. The @code{(gnu
12457 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
12458 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
12460 The example below defines an operating system that provides log rotation
12461 with the default settings, for commonly encountered log files.
12464 (use-modules (guix) (gnu))
12465 (use-service-modules admin mcron)
12466 (use-package-modules base idutils)
12470 (services (cons (service rottlog-service-type)
12474 @defvr {Scheme Variable} rottlog-service-type
12475 This is the type of the Rottlog service, whose value is a
12476 @code{rottlog-configuration} object.
12478 Other services can extend this one with new @code{log-rotation} objects
12479 (see below), thereby augmenting the set of files to be rotated.
12481 This service type can define mcron jobs (@pxref{Scheduled Job
12482 Execution}) to run the rottlog service.
12485 @deftp {Data Type} rottlog-configuration
12486 Data type representing the configuration of rottlog.
12489 @item @code{rottlog} (default: @code{rottlog})
12490 The Rottlog package to use.
12492 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
12493 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
12494 rottlog, GNU Rot[t]log Manual}).
12496 @item @code{rotations} (default: @code{%default-rotations})
12497 A list of @code{log-rotation} objects as defined below.
12500 This is a list of gexps where each gexp corresponds to an mcron job
12501 specification (@pxref{Scheduled Job Execution}).
12505 @deftp {Data Type} log-rotation
12506 Data type representing the rotation of a group of log files.
12508 Taking an example from the Rottlog manual (@pxref{Period Related File
12509 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
12515 (files '("/var/log/apache/*"))
12516 (options '("storedir apache-archives"
12522 The list of fields is as follows:
12525 @item @code{frequency} (default: @code{'weekly})
12526 The log rotation frequency, a symbol.
12529 The list of files or file glob patterns to rotate.
12531 @item @code{options} (default: @code{'()})
12532 The list of rottlog options for this rotation (@pxref{Configuration
12533 parameters,,, rottlog, GNU Rot[t]lg Manual}).
12535 @item @code{post-rotate} (default: @code{#f})
12536 Either @code{#f} or a gexp to execute once the rotation has completed.
12540 @defvr {Scheme Variable} %default-rotations
12541 Specifies weekly rotation of @var{%rotated-files} and
12542 a couple of other files.
12545 @defvr {Scheme Variable} %rotated-files
12546 The list of syslog-controlled files to be rotated. By default it is:
12547 @code{'("/var/log/messages" "/var/log/secure")}.
12550 @node Networking Services
12551 @subsection Networking Services
12553 The @code{(gnu services networking)} module provides services to configure
12554 the network interface.
12556 @cindex DHCP, networking service
12557 @defvr {Scheme Variable} dhcp-client-service-type
12558 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
12559 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
12560 is the DHCP client package to use, @code{isc-dhcp} by default.
12563 @deffn {Scheme Procedure} dhcpd-service-type
12564 This type defines a service that runs a DHCP daemon. To create a
12565 service of this type, you must supply a @code{<dhcpd-configuration>}.
12569 (service dhcpd-service-type
12570 (dhcpd-configuration
12571 (config-file (local-file "my-dhcpd.conf"))
12572 (interfaces '("enp0s25"))))
12576 @deftp {Data Type} dhcpd-configuration
12578 @item @code{package} (default: @code{isc-dhcp})
12579 The package that provides the DHCP daemon. This package is expected to
12580 provide the daemon at @file{sbin/dhcpd} relative to its output
12581 directory. The default package is the
12582 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
12583 @item @code{config-file} (default: @code{#f})
12584 The configuration file to use. This is required. It will be passed to
12585 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
12586 object (@pxref{G-Expressions, file-like objects}). See @code{man
12587 dhcpd.conf} for details on the configuration file syntax.
12588 @item @code{version} (default: @code{"4"})
12589 The DHCP version to use. The ISC DHCP server supports the values ``4'',
12590 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
12591 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
12593 @item @code{run-directory} (default: @code{"/run/dhcpd"})
12594 The run directory to use. At service activation time, this directory
12595 will be created if it does not exist.
12596 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
12597 The PID file to use. This corresponds to the @code{-pf} option of
12598 @code{dhcpd}. See @code{man dhcpd} for details.
12599 @item @code{interfaces} (default: @code{'()})
12600 The names of the network interfaces on which dhcpd should listen for
12601 broadcasts. If this list is not empty, then its elements (which must be
12602 strings) will be appended to the @code{dhcpd} invocation when starting
12603 the daemon. It may not be necessary to explicitly specify any
12604 interfaces here; see @code{man dhcpd} for details.
12608 @defvr {Scheme Variable} static-networking-service-type
12609 This is the type for statically-configured network interfaces.
12610 @c TODO Document <static-networking> data structures.
12613 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
12614 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
12615 [#:requirement @code{'(udev)}]
12616 Return a service that starts @var{interface} with address @var{ip}. If
12617 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
12618 it must be a string specifying the default network gateway. @var{requirement}
12619 can be used to declare a dependency on another service before configuring the
12622 This procedure can be called several times, one for each network
12623 interface of interest. Behind the scenes what it does is extend
12624 @code{static-networking-service-type} with additional network interfaces
12630 (static-networking-service "eno1" "192.168.1.82"
12631 #:gateway "192.168.1.2"
12632 #:name-servers '("192.168.1.2"))
12639 @cindex network management
12640 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
12641 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
12642 management daemon that aims to simplify wired and wireless networking.
12644 This service adds the @var{wicd} package to the global profile, providing
12645 several commands to interact with the daemon and configure networking:
12646 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
12647 and @command{wicd-curses} user interfaces.
12650 @cindex ModemManager
12652 @defvr {Scheme Variable} modem-manager-service-type
12653 This is the service type for the
12654 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
12655 service. The value for this service type is a
12656 @code{modem-manager-configuration} record.
12658 This service is part of @code{%desktop-services} (@pxref{Desktop
12662 @deftp {Data Type} modem-manager-configuration
12663 Data type representing the configuration of ModemManager.
12666 @item @code{modem-manager} (default: @code{modem-manager})
12667 The ModemManager package to use.
12672 @cindex USB_ModeSwitch
12673 @cindex Modeswitching
12675 @defvr {Scheme Variable} usb-modeswitch-service-type
12676 This is the service type for the
12677 @uref{http://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
12678 value for this service type is a @code{usb-modeswitch-configuration} record.
12680 When plugged in, some USB modems (and other USB devices) initially present
12681 themselves as a read-only storage medium and not as a modem. They need to be
12682 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
12683 installs udev rules to automatically modeswitch these devices when they are
12686 This service is part of @code{%desktop-services} (@pxref{Desktop
12690 @deftp {Data Type} usb-modeswitch-configuration
12691 Data type representing the configuration of USB_ModeSwitch.
12694 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
12695 The USB_ModeSwitch package providing the binaries for modeswitching.
12697 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
12698 The package providing the device data and udev rules file used by
12701 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
12702 Which config file to use for the USB_ModeSwitch dispatcher. By default the
12703 config file shipped with USB_ModeSwitch is used which disables logging to
12704 @file{/var/log} among other default settings. If set to @code{#f}, no config
12710 @cindex NetworkManager
12712 @defvr {Scheme Variable} network-manager-service-type
12713 This is the service type for the
12714 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
12715 service. The value for this service type is a
12716 @code{network-manager-configuration} record.
12718 This service is part of @code{%desktop-services} (@pxref{Desktop
12722 @deftp {Data Type} network-manager-configuration
12723 Data type representing the configuration of NetworkManager.
12726 @item @code{network-manager} (default: @code{network-manager})
12727 The NetworkManager package to use.
12729 @item @code{dns} (default: @code{"default"})
12730 Processing mode for DNS, which affects how NetworkManager uses the
12731 @code{resolv.conf} configuration file.
12735 NetworkManager will update @code{resolv.conf} to reflect the nameservers
12736 provided by currently active connections.
12739 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
12740 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
12741 then update @code{resolv.conf} to point to the local nameserver.
12743 With this setting, you can share your network connection. For example when
12744 you want to share your network connection to another laptop @i{via} an
12745 Ethernet cable, you can open @command{nm-connection-editor} and configure the
12746 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
12747 and reestablish the connection (or reboot).
12749 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
12750 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
12751 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
12752 browser on your host system, or connect to the VM @i{via} SSH
12753 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
12754 host-to-guest connection, run this command once:
12757 nmcli connection add type tun \
12758 connection.interface-name tap0 \
12759 tun.mode tap tun.owner $(id -u) \
12760 ipv4.method shared \
12761 ipv4.addresses 172.28.112.1/24
12764 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
12765 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
12766 @command{qemu-system-...}.
12769 NetworkManager will not modify @code{resolv.conf}.
12772 @item @code{vpn-plugins} (default: @code{'()})
12773 This is the list of available plugins for virtual private networks
12774 (VPNs). An example of this is the @code{network-manager-openvpn}
12775 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
12781 @deffn {Scheme Variable} connman-service-type
12782 This is the service type to run @url{https://01.org/connman,Connman},
12783 a network connection manager.
12785 Its value must be an
12786 @code{connman-configuration} record as in this example:
12789 (service connman-service-type
12790 (connman-configuration
12791 (disable-vpn? #t)))
12794 See below for details about @code{connman-configuration}.
12797 @deftp {Data Type} connman-configuration
12798 Data Type representing the configuration of connman.
12801 @item @code{connman} (default: @var{connman})
12802 The connman package to use.
12804 @item @code{disable-vpn?} (default: @code{#f})
12805 When true, disable connman's vpn plugin.
12809 @cindex WPA Supplicant
12810 @defvr {Scheme Variable} wpa-supplicant-service-type
12811 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
12812 supplicant}, an authentication daemon required to authenticate against
12813 encrypted WiFi or ethernet networks.
12816 @deftp {Data Type} wpa-supplicant-configuration
12817 Data type representing the configuration of WPA Supplicant.
12819 It takes the following parameters:
12822 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
12823 The WPA Supplicant package to use.
12825 @item @code{dbus?} (default: @code{#t})
12826 Whether to listen for requests on D-Bus.
12828 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
12829 Where to store the PID file.
12831 @item @code{interface} (default: @code{#f})
12832 If this is set, it must specify the name of a network interface that
12833 WPA supplicant will control.
12835 @item @code{config-file} (default: @code{#f})
12836 Optional configuration file to use.
12838 @item @code{extra-options} (default: @code{'()})
12839 List of additional command-line arguments to pass to the daemon.
12844 @defvr {Scheme Variable} iptables-service-type
12845 This is the service type to set up an iptables configuration. iptables is a
12846 packet filtering framework supported by the Linux kernel. This service
12847 supports configuring iptables for both IPv4 and IPv6. A simple example
12848 configuration rejecting all incoming connections except those to the ssh port
12852 (service iptables-service-type
12853 (iptables-configuration
12854 (ipv4-rules (plain-file "iptables.rules" "*filter
12858 -A INPUT -p tcp --dport 22 -j ACCEPT
12859 -A INPUT -j REJECT --reject-with icmp-port-unreachable
12862 (ipv6-rules (plain-file "ip6tables.rules" "*filter
12866 -A INPUT -p tcp --dport 22 -j ACCEPT
12867 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
12873 @deftp {Data Type} iptables-configuration
12874 The data type representing the configuration of iptables.
12877 @item @code{iptables} (default: @code{iptables})
12878 The iptables package that provides @code{iptables-restore} and
12879 @code{ip6tables-restore}.
12880 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
12881 The iptables rules to use. It will be passed to @code{iptables-restore}.
12882 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
12884 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
12885 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
12886 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
12891 @cindex NTP (Network Time Protocol), service
12892 @cindex real time clock
12893 @defvr {Scheme Variable} ntp-service-type
12894 This is the type of the service running the @uref{http://www.ntp.org,
12895 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
12896 system clock synchronized with that of the specified NTP servers.
12898 The value of this service is an @code{ntpd-configuration} object, as described
12902 @deftp {Data Type} ntp-configuration
12903 This is the data type for the NTP service configuration.
12906 @item @code{servers} (default: @code{%ntp-servers})
12907 This is the list of servers (host names) with which @command{ntpd} will be
12910 @item @code{allow-large-adjustment?} (default: @code{#f})
12911 This determines whether @command{ntpd} is allowed to make an initial
12912 adjustment of more than 1,000 seconds.
12914 @item @code{ntp} (default: @code{ntp})
12915 The NTP package to use.
12919 @defvr {Scheme Variable} %ntp-servers
12920 List of host names used as the default NTP servers. These are servers of the
12921 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
12925 @deffn {Scheme Procedure} openntpd-service-type
12926 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
12927 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
12928 clock synchronized with that of the given servers.
12932 openntpd-service-type
12933 (openntpd-configuration
12934 (listen-on '("127.0.0.1" "::1"))
12935 (sensor '("udcf0 correction 70000"))
12936 (constraint-from '("www.gnu.org"))
12937 (constraints-from '("https://www.google.com/"))
12938 (allow-large-adjustment? #t)))
12943 @deftp {Data Type} openntpd-configuration
12945 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
12946 The openntpd executable to use.
12947 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
12948 A list of local IP addresses or hostnames the ntpd daemon should listen on.
12949 @item @code{query-from} (default: @code{'()})
12950 A list of local IP address the ntpd daemon should use for outgoing queries.
12951 @item @code{sensor} (default: @code{'()})
12952 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
12953 will listen to each sensor that actually exists and ignore non-existent ones.
12954 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
12956 @item @code{server} (default: @var{%ntp-servers})
12957 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
12958 @item @code{servers} (default: @code{'()})
12959 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
12960 @item @code{constraint-from} (default: @code{'()})
12961 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
12962 This time information is not used for precision but acts as an authenticated
12963 constraint, thereby reducing the impact of unauthenticated NTP
12964 man-in-the-middle attacks.
12965 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
12967 @item @code{constraints-from} (default: @code{'()})
12968 As with constraint from, specify a list of URLs, IP addresses or hostnames of
12969 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
12970 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
12971 @item @code{allow-large-adjustment?} (default: @code{#f})
12972 Determines if @code{ntpd} is allowed to make an initial adjustment of more
12978 @deffn {Scheme variable} inetd-service-type
12979 This service runs the @command{inetd} (@pxref{inetd invocation,,,
12980 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
12981 connections on internet sockets, and lazily starts the specified server
12982 program when a connection is made on one of these sockets.
12984 The value of this service is an @code{inetd-configuration} object. The
12985 following example configures the @command{inetd} daemon to provide the
12986 built-in @command{echo} service, as well as an smtp service which
12987 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
12988 gateway @code{hostname}:
12993 (inetd-configuration
12997 (socket-type 'stream)
13004 (socket-type 'stream)
13008 (program (file-append openssh "/bin/ssh"))
13010 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13011 "-W" "smtp-server:25" "user@@hostname")))))
13014 See below for more details about @code{inetd-configuration}.
13017 @deftp {Data Type} inetd-configuration
13018 Data type representing the configuration of @command{inetd}.
13021 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13022 The @command{inetd} executable to use.
13024 @item @code{entries} (default: @code{'()})
13025 A list of @command{inetd} service entries. Each entry should be created
13026 by the @code{inetd-entry} constructor.
13030 @deftp {Data Type} inetd-entry
13031 Data type representing an entry in the @command{inetd} configuration.
13032 Each entry corresponds to a socket where @command{inetd} will listen for
13036 @item @code{node} (default: @code{#f})
13037 Optional string, a comma-separated list of local addresses
13038 @command{inetd} should use when listening for this service.
13039 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13040 description of all options.
13042 A string, the name must correspond to an entry in @code{/etc/services}.
13043 @item @code{socket-type}
13044 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13046 @item @code{protocol}
13047 A string, must correspond to an entry in @code{/etc/protocols}.
13048 @item @code{wait?} (default: @code{#t})
13049 Whether @command{inetd} should wait for the server to exit before
13050 listening to new service requests.
13052 A string containing the user (and, optionally, group) name of the user
13053 as whom the server should run. The group name can be specified in a
13054 suffix, separated by a colon or period, i.e.@: @code{"user"},
13055 @code{"user:group"} or @code{"user.group"}.
13056 @item @code{program} (default: @code{"internal"})
13057 The server program which will serve the requests, or @code{"internal"}
13058 if @command{inetd} should use a built-in service.
13059 @item @code{arguments} (default: @code{'()})
13060 A list strings or file-like objects, which are the server program's
13061 arguments, starting with the zeroth argument, i.e.@: the name of the
13062 program itself. For @command{inetd}'s internal services, this entry
13063 must be @code{'()} or @code{'("internal")}.
13066 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13067 detailed discussion of each configuration field.
13071 @defvr {Scheme Variable} tor-service-type
13072 This is the type for a service that runs the @uref{https://torproject.org,
13073 Tor} anonymous networking daemon. The service is configured using a
13074 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
13075 @code{tor} unprivileged user, which is a member of the @code{tor} group.
13079 @deftp {Data Type} tor-configuration
13081 @item @code{tor} (default: @code{tor})
13082 The package that provides the Tor daemon. This package is expected to provide
13083 the daemon at @file{bin/tor} relative to its output directory. The default
13084 package is the @uref{https://www.torproject.org, Tor Project's}
13087 @item @code{config-file} (default: @code{(plain-file "empty" "")})
13088 The configuration file to use. It will be appended to a default configuration
13089 file, and the final configuration file will be passed to @code{tor} via its
13090 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
13091 file-like objects}). See @code{man tor} for details on the configuration file
13094 @item @code{hidden-services} (default: @code{'()})
13095 The list of @code{<hidden-service>} records to use. For any hidden service
13096 you include in this list, appropriate configuration to enable the hidden
13097 service will be automatically added to the default configuration file. You
13098 may conveniently create @code{<hidden-service>} records using the
13099 @code{tor-hidden-service} procedure described below.
13101 @item @code{socks-socket-type} (default: @code{'tcp})
13102 The default socket type that Tor should use for its SOCKS socket. This must
13103 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
13104 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
13105 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
13106 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13109 If you want to customize the SOCKS socket in more detail, leave
13110 @code{socks-socket-type} at its default value of @code{'tcp} and use
13111 @code{config-file} to override the default by providing your own
13112 @code{SocksPort} option.
13116 @cindex hidden service
13117 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13118 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13119 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13122 '((22 "127.0.0.1:22")
13123 (80 "127.0.0.1:8080"))
13126 In this example, port 22 of the hidden service is mapped to local port 22, and
13127 port 80 is mapped to local port 8080.
13129 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13130 the @file{hostname} file contains the @code{.onion} host name for the hidden
13133 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13134 project's documentation} for more information.
13137 The @code{(gnu services rsync)} module provides the following services:
13139 You might want an rsync daemon if you have files that you want available
13140 so anyone (or just yourself) can download existing files or upload new
13143 @deffn {Scheme Variable} rsync-service-type
13144 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13145 The value for this service type is a
13146 @command{rsync-configuration} record as in this example:
13149 (service rsync-service-type)
13152 See below for details about @code{rsync-configuration}.
13155 @deftp {Data Type} rsync-configuration
13156 Data type representing the configuration for @code{rsync-service}.
13159 @item @code{package} (default: @var{rsync})
13160 @code{rsync} package to use.
13162 @item @code{port-number} (default: @code{873})
13163 TCP port on which @command{rsync} listens for incoming connections. If port
13164 is less than @code{1024} @command{rsync} needs to be started as the
13165 @code{root} user and group.
13167 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
13168 Name of the file where @command{rsync} writes its PID.
13170 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
13171 Name of the file where @command{rsync} writes its lock file.
13173 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
13174 Name of the file where @command{rsync} writes its log file.
13176 @item @code{use-chroot?} (default: @var{#t})
13177 Whether to use chroot for @command{rsync} shared directory.
13179 @item @code{share-path} (default: @file{/srv/rsync})
13180 Location of the @command{rsync} shared directory.
13182 @item @code{share-comment} (default: @code{"Rsync share"})
13183 Comment of the @command{rsync} shared directory.
13185 @item @code{read-only?} (default: @var{#f})
13186 Read-write permissions to shared directory.
13188 @item @code{timeout} (default: @code{300})
13189 I/O timeout in seconds.
13191 @item @code{user} (default: @var{"root"})
13192 Owner of the @code{rsync} process.
13194 @item @code{group} (default: @var{"root"})
13195 Group of the @code{rsync} process.
13197 @item @code{uid} (default: @var{"rsyncd"})
13198 User name or user ID that file transfers to and from that module should take
13199 place as when the daemon was run as @code{root}.
13201 @item @code{gid} (default: @var{"rsyncd"})
13202 Group name or group ID that will be used when accessing the module.
13207 Furthermore, @code{(gnu services ssh)} provides the following services.
13211 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
13212 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
13213 [#:allow-empty-passwords? #f] [#:root-login? #f] @
13214 [#:syslog-output? #t] [#:x11-forwarding? #t] @
13215 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
13216 [#:public-key-authentication? #t] [#:initialize? #t]
13217 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
13218 @var{host-key} must designate a file containing the host key, and readable
13221 When @var{daemonic?} is true, @command{lshd} will detach from the
13222 controlling terminal and log its output to syslogd, unless one sets
13223 @var{syslog-output?} to false. Obviously, it also makes lsh-service
13224 depend on existence of syslogd service. When @var{pid-file?} is true,
13225 @command{lshd} writes its PID to the file called @var{pid-file}.
13227 When @var{initialize?} is true, automatically create the seed and host key
13228 upon service activation if they do not exist yet. This may take long and
13229 require interaction.
13231 When @var{initialize?} is false, it is up to the user to initialize the
13232 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
13233 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
13234 basics,,, lsh, LSH Manual}).
13236 When @var{interfaces} is empty, lshd listens for connections on all the
13237 network interfaces; otherwise, @var{interfaces} must be a list of host names
13240 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
13241 passwords, and @var{root-login?} specifies whether to accept log-ins as
13244 The other options should be self-descriptive.
13249 @deffn {Scheme Variable} openssh-service-type
13250 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
13251 shell daemon, @command{sshd}. Its value must be an
13252 @code{openssh-configuration} record as in this example:
13255 (service openssh-service-type
13256 (openssh-configuration
13257 (x11-forwarding? #t)
13258 (permit-root-login 'without-password)
13260 `(("alice" ,(local-file "alice.pub"))
13261 ("bob" ,(local-file "bob.pub"))))))
13264 See below for details about @code{openssh-configuration}.
13266 This service can be extended with extra authorized keys, as in this
13270 (service-extension openssh-service-type
13271 (const `(("charlie"
13272 ,(local-file "charlie.pub")))))
13276 @deftp {Data Type} openssh-configuration
13277 This is the configuration record for OpenSSH's @command{sshd}.
13280 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
13281 Name of the file where @command{sshd} writes its PID.
13283 @item @code{port-number} (default: @code{22})
13284 TCP port on which @command{sshd} listens for incoming connections.
13286 @item @code{permit-root-login} (default: @code{#f})
13287 This field determines whether and when to allow logins as root. If
13288 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
13289 If it's the symbol @code{'without-password}, then root logins are
13290 permitted but not with password-based authentication.
13292 @item @code{allow-empty-passwords?} (default: @code{#f})
13293 When true, users with empty passwords may log in. When false, they may
13296 @item @code{password-authentication?} (default: @code{#t})
13297 When true, users may log in with their password. When false, they have
13298 other authentication methods.
13300 @item @code{public-key-authentication?} (default: @code{#t})
13301 When true, users may log in using public key authentication. When
13302 false, users have to use other authentication method.
13304 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
13305 This is used only by protocol version 2.
13307 @item @code{x11-forwarding?} (default: @code{#f})
13308 When true, forwarding of X11 graphical client connections is
13309 enabled---in other words, @command{ssh} options @option{-X} and
13310 @option{-Y} will work.
13312 @item @code{allow-agent-forwarding?} (default: @code{#t})
13313 Whether to allow agent forwarding.
13315 @item @code{allow-tcp-forwarding?} (default: @code{#t})
13316 Whether to allow TCP forwarding.
13318 @item @code{gateway-ports?} (default: @code{#f})
13319 Whether to allow gateway ports.
13321 @item @code{challenge-response-authentication?} (default: @code{#f})
13322 Specifies whether challenge response authentication is allowed (e.g.@: via
13325 @item @code{use-pam?} (default: @code{#t})
13326 Enables the Pluggable Authentication Module interface. If set to
13327 @code{#t}, this will enable PAM authentication using
13328 @code{challenge-response-authentication?} and
13329 @code{password-authentication?}, in addition to PAM account and session
13330 module processing for all authentication types.
13332 Because PAM challenge response authentication usually serves an
13333 equivalent role to password authentication, you should disable either
13334 @code{challenge-response-authentication?} or
13335 @code{password-authentication?}.
13337 @item @code{print-last-log?} (default: @code{#t})
13338 Specifies whether @command{sshd} should print the date and time of the
13339 last user login when a user logs in interactively.
13341 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
13342 Configures external subsystems (e.g.@: file transfer daemon).
13344 This is a list of two-element lists, each of which containing the
13345 subsystem name and a command (with optional arguments) to execute upon
13348 The command @command{internal-sftp} implements an in-process SFTP
13349 server. Alternately, one can specify the @command{sftp-server} command:
13351 (service openssh-service-type
13352 (openssh-configuration
13354 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
13357 @item @code{accepted-environment} (default: @code{'()})
13358 List of strings describing which environment variables may be exported.
13360 Each string gets on its own line. See the @code{AcceptEnv} option in
13361 @code{man sshd_config}.
13363 This example allows ssh-clients to export the @code{COLORTERM} variable.
13364 It is set by terminal emulators, which support colors. You can use it in
13365 your shell's ressource file to enable colors for the prompt and commands
13366 if this variable is set.
13369 (service openssh-service-type
13370 (openssh-configuration
13371 (accepted-environment '("COLORTERM"))))
13374 @item @code{authorized-keys} (default: @code{'()})
13375 @cindex authorized keys, SSH
13376 @cindex SSH authorized keys
13377 This is the list of authorized keys. Each element of the list is a user
13378 name followed by one or more file-like objects that represent SSH public
13382 (openssh-configuration
13384 `(("rekado" ,(local-file "rekado.pub"))
13385 ("chris" ,(local-file "chris.pub"))
13386 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
13390 registers the specified public keys for user accounts @code{rekado},
13391 @code{chris}, and @code{root}.
13393 Additional authorized keys can be specified @i{via}
13394 @code{service-extension}.
13396 Note that this does @emph{not} interfere with the use of
13397 @file{~/.ssh/authorized_keys}.
13399 @item @code{log-level} (default: @code{'info})
13400 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
13401 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
13402 page for @file{sshd_config} for the full list of level names.
13404 @item @code{extra-content} (default: @code{""})
13405 This field can be used to append arbitrary text to the configuration file. It
13406 is especially useful for elaborate configurations that cannot be expressed
13407 otherwise. This configuration, for example, would generally disable root
13408 logins, but permit them from one specific IP address:
13411 (openssh-configuration
13413 Match Address 192.168.0.1
13414 PermitRootLogin yes"))
13420 @deffn {Scheme Procedure} dropbear-service [@var{config}]
13421 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
13422 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
13425 For example, to specify a Dropbear service listening on port 1234, add
13426 this call to the operating system's @code{services} field:
13429 (dropbear-service (dropbear-configuration
13430 (port-number 1234)))
13434 @deftp {Data Type} dropbear-configuration
13435 This data type represents the configuration of a Dropbear SSH daemon.
13438 @item @code{dropbear} (default: @var{dropbear})
13439 The Dropbear package to use.
13441 @item @code{port-number} (default: 22)
13442 The TCP port where the daemon waits for incoming connections.
13444 @item @code{syslog-output?} (default: @code{#t})
13445 Whether to enable syslog output.
13447 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
13448 File name of the daemon's PID file.
13450 @item @code{root-login?} (default: @code{#f})
13451 Whether to allow @code{root} logins.
13453 @item @code{allow-empty-passwords?} (default: @code{#f})
13454 Whether to allow empty passwords.
13456 @item @code{password-authentication?} (default: @code{#t})
13457 Whether to enable password-based authentication.
13461 @defvr {Scheme Variable} %facebook-host-aliases
13462 This variable contains a string for use in @file{/etc/hosts}
13463 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
13464 line contains a entry that maps a known server name of the Facebook
13465 on-line service---e.g., @code{www.facebook.com}---to the local
13466 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
13468 This variable is typically used in the @code{hosts-file} field of an
13469 @code{operating-system} declaration (@pxref{operating-system Reference,
13470 @file{/etc/hosts}}):
13473 (use-modules (gnu) (guix))
13476 (host-name "mymachine")
13479 ;; Create a /etc/hosts file with aliases for "localhost"
13480 ;; and "mymachine", as well as for Facebook servers.
13481 (plain-file "hosts"
13482 (string-append (local-host-aliases host-name)
13483 %facebook-host-aliases))))
13486 This mechanism can prevent programs running locally, such as Web
13487 browsers, from accessing Facebook.
13490 The @code{(gnu services avahi)} provides the following definition.
13492 @defvr {Scheme Variable} avahi-service-type
13493 This is the service that runs @command{avahi-daemon}, a system-wide
13494 mDNS/DNS-SD responder that allows for service discovery and
13495 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
13496 Its value must be a @code{zero-configuration} record---see below.
13498 This service extends the name service cache daemon (nscd) so that it can
13499 resolve @code{.local} host names using
13500 @uref{http://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
13501 Service Switch}, for information on host name resolution.
13503 Additionally, add the @var{avahi} package to the system profile so that
13504 commands such as @command{avahi-browse} are directly usable.
13507 @deftp {Data Type} avahi-configuration
13508 Data type representation the configuration for Avahi.
13512 @item @code{host-name} (default: @code{#f})
13513 If different from @code{#f}, use that as the host name to
13514 publish for this machine; otherwise, use the machine's actual host name.
13516 @item @code{publish?} (default: @code{#t})
13517 When true, allow host names and services to be published (broadcast) over the
13520 @item @code{publish-workstation?} (default: @code{#t})
13521 When true, @command{avahi-daemon} publishes the machine's host name and IP
13522 address via mDNS on the local network. To view the host names published on
13523 your local network, you can run:
13526 avahi-browse _workstation._tcp
13529 @item @code{wide-area?} (default: @code{#f})
13530 When true, DNS-SD over unicast DNS is enabled.
13532 @item @code{ipv4?} (default: @code{#t})
13533 @itemx @code{ipv6?} (default: @code{#t})
13534 These fields determine whether to use IPv4/IPv6 sockets.
13536 @item @code{domains-to-browse} (default: @code{'()})
13537 This is a list of domains to browse.
13541 @deffn {Scheme Variable} openvswitch-service-type
13542 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
13543 service, whose value should be an @code{openvswitch-configuration}
13547 @deftp {Data Type} openvswitch-configuration
13548 Data type representing the configuration of Open vSwitch, a multilayer
13549 virtual switch which is designed to enable massive network automation
13550 through programmatic extension.
13553 @item @code{package} (default: @var{openvswitch})
13554 Package object of the Open vSwitch.
13560 @subsection X Window
13563 @cindex X Window System
13564 @cindex login manager
13565 Support for the X Window graphical display system---specifically
13566 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
13567 there is no @code{xorg-service} procedure. Instead, the X server is
13568 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
13571 @cindex GNOME, login manager
13572 GDM of course allows users to log in into window managers and desktop
13573 environments other than GNOME; for those using GNOME, GDM is required for
13574 features such as automatic screen locking.
13576 @cindex window manager
13577 To use X11, you must install at least one @dfn{window manager}---for
13578 example the @code{windowmaker} or @code{openbox} packages---preferably
13579 by adding it to the @code{packages} field of your operating system
13580 definition (@pxref{operating-system Reference, system-wide packages}).
13582 @defvr {Scheme Variable} gdm-service-type
13583 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
13584 Desktop Manager} (GDM), a program that manages graphical display servers and
13585 handles graphical user logins. Its value must be a @code{gdm-configuration}
13588 @cindex session types (X11)
13589 @cindex X11 session types
13590 GDM looks for @dfn{session types} described by the @file{.desktop} files in
13591 @file{/run/current-system/profile/share/xsessions} and allows users to choose
13592 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
13593 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
13594 set of packages automatically makes them available at the log-in screen.
13596 In addition, @file{~/.xsession} files are honored. When available,
13597 @file{~/.xsession} must be an executable that starts a window manager
13598 and/or other X clients.
13601 @deftp {Data Type} gdm-configuration
13603 @item @code{auto-login?} (default: @code{#f})
13604 @itemx @code{default-user} (default: @code{#f})
13605 When @code{auto-login?} is false, GDM presents a log-in screen.
13607 When @code{auto-login?} is true, GDM logs in directly as
13608 @code{default-user}.
13610 @item @code{gnome-shell-assets} (default: ...)
13611 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
13613 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
13614 Configuration of the Xorg graphical server.
13616 @item @code{xsession} (default: @code{(xinitrc)})
13617 Script to run before starting a X session.
13619 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
13620 File name of the @code{dbus-daemon} executable.
13622 @item @code{gdm} (default: @code{gdm})
13623 The GDM package to use.
13627 @defvr {Scheme Variable} slim-service-type
13628 This is the type for the SLiM graphical login manager for X11.
13630 Like GDM, SLiM looks for session types described by @file{.desktop} files and
13631 allows users to choose a session from the log-in screen using @kbd{F1}. It
13632 also honors @file{~/.xsession} files.
13634 Unlike GDM, SLiM does not spawn the user session on a different VT after
13635 logging in, which means that you can only start one graphical session. If you
13636 want to be able to run multiple graphical sessions at the same time you have
13637 to add multiple SLiM services to your system services. The following example
13638 shows how to replace the default GDM service with two SLiM services on tty7
13642 (use-modules (gnu services)
13643 (gnu services desktop)
13644 (gnu services xorg)
13645 (srfi srfi-1)) ;for 'remove'
13649 (services (cons* (service slim-service-type (slim-configuration
13652 (service slim-service-type (slim-configuration
13655 (remove (lambda (service)
13656 (eq? (service-kind service) gdm-service-type))
13657 %desktop-services))))
13662 @deftp {Data Type} slim-configuration
13663 Data type representing the configuration of @code{slim-service-type}.
13666 @item @code{allow-empty-passwords?} (default: @code{#t})
13667 Whether to allow logins with empty passwords.
13669 @item @code{auto-login?} (default: @code{#f})
13670 @itemx @code{default-user} (default: @code{""})
13671 When @code{auto-login?} is false, SLiM presents a log-in screen.
13673 When @code{auto-login?} is true, SLiM logs in directly as
13674 @code{default-user}.
13676 @item @code{theme} (default: @code{%default-slim-theme})
13677 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
13678 The graphical theme to use and its name.
13680 @item @code{auto-login-session} (default: @code{#f})
13681 If true, this must be the name of the executable to start as the default
13682 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
13684 If false, a session described by one of the available @file{.desktop}
13685 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
13689 You must install at least one window manager in the system profile or in
13690 your user profile. Failing to do that, if @code{auto-login-session} is
13691 false, you will be unable to log in.
13694 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13695 Configuration of the Xorg graphical server.
13697 @item @code{display} (default @code{":0"})
13698 The display on which to start the Xorg graphical server.
13700 @item @code{vt} (default @code{"vt7"})
13701 The VT on which to start the Xorg graphical server.
13703 @item @code{xauth} (default: @code{xauth})
13704 The XAuth package to use.
13706 @item @code{shepherd} (default: @code{shepherd})
13707 The Shepherd package used when invoking @command{halt} and
13710 @item @code{sessreg} (default: @code{sessreg})
13711 The sessreg package used in order to register the session.
13713 @item @code{slim} (default: @code{slim})
13714 The SLiM package to use.
13718 @defvr {Scheme Variable} %default-theme
13719 @defvrx {Scheme Variable} %default-theme-name
13720 The default SLiM theme and its name.
13724 @deftp {Data Type} sddm-configuration
13725 This is the data type representing the sddm service configuration.
13728 @item @code{display-server} (default: "x11")
13729 Select display server to use for the greeter. Valid values are "x11"
13732 @item @code{numlock} (default: "on")
13733 Valid values are "on", "off" or "none".
13735 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
13736 Command to run when halting.
13738 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
13739 Command to run when rebooting.
13741 @item @code{theme} (default "maldives")
13742 Theme to use. Default themes provided by SDDM are "elarun" or "maldives".
13744 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
13745 Directory to look for themes.
13747 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
13748 Directory to look for faces.
13750 @item @code{default-path} (default "/run/current-system/profile/bin")
13751 Default PATH to use.
13753 @item @code{minimum-uid} (default: 1000)
13754 Minimum UID displayed in SDDM and allowed for log-in.
13756 @item @code{maximum-uid} (default: 2000)
13757 Maximum UID to display in SDDM.
13759 @item @code{remember-last-user?} (default #t)
13760 Remember last user.
13762 @item @code{remember-last-session?} (default #t)
13763 Remember last session.
13765 @item @code{hide-users} (default "")
13766 Usernames to hide from SDDM greeter.
13768 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
13769 Users with shells listed will be hidden from the SDDM greeter.
13771 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
13772 Script to run before starting a wayland session.
13774 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
13775 Directory to look for desktop files starting wayland sessions.
13777 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
13778 Configuration of the Xorg graphical server.
13780 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
13783 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
13786 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
13787 Script to run after starting xorg-server.
13789 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
13790 Script to run before stopping xorg-server.
13792 @item @code{xsession-command} (default: @code{xinitrc})
13793 Script to run before starting a X session.
13795 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
13796 Directory to look for desktop files starting X sessions.
13798 @item @code{minimum-vt} (default: 7)
13801 @item @code{auto-login-user} (default "")
13802 User to use for auto-login.
13804 @item @code{auto-login-session} (default "")
13805 Desktop file to use for auto-login.
13807 @item @code{relogin?} (default #f)
13808 Relogin after logout.
13813 @cindex login manager
13815 @deffn {Scheme Procedure} sddm-service config
13816 Return a service that spawns the SDDM graphical login manager for config of
13817 type @code{<sddm-configuration>}.
13820 (sddm-service (sddm-configuration
13821 (auto-login-user "Alice")
13822 (auto-login-session "xfce.desktop")))
13826 @cindex Xorg, configuration
13827 @deftp {Data Type} xorg-configuration
13828 This data type represents the configuration of the Xorg graphical display
13829 server. Note that there is not Xorg service; instead, the X server is started
13830 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
13831 of these display managers aggregates an @code{xorg-configuration} record.
13834 @item @code{modules} (default: @code{%default-xorg-modules})
13835 This is a list of @dfn{module packages} loaded by the Xorg
13836 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
13838 @item @code{fonts} (default: @code{%default-xorg-fonts})
13839 This is a list of font directories to add to the server's @dfn{font path}.
13841 @item @code{drivers} (default: @code{'()})
13842 This must be either the empty list, in which case Xorg chooses a graphics
13843 driver automatically, or a list of driver names that will be tried in this
13844 order---e.g., @code{("modesetting" "vesa")}.
13846 @item @code{resolutions} (default: @code{'()})
13847 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
13848 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
13851 @cindex keyboard layout, for Xorg
13852 @cindex keymap, for Xorg
13853 @item @code{keyboard-layout} (default: @code{#f})
13854 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
13855 English (``qwerty'') for a 105-key PC keyboard.
13857 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
13858 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
13859 information on how to specify the keyboard layout.
13861 @item @code{extra-config} (default: @code{'()})
13862 This is a list of strings or objects appended to the configuration file. It
13863 is used to pass extra text to be added verbatim to the configuration file.
13865 @item @code{server} (default: @code{xorg-server})
13866 This is the package providing the Xorg server.
13868 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
13869 This is the list of command-line arguments to pass to the X server. The
13870 default is @code{-nolisten tcp}.
13874 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
13875 [@var{login-manager-service-type}]
13876 Tell the log-in manager (of type @var{login-manager-service-type}) to use
13877 @var{config}, an @code{<xorg-configuration>} record.
13879 Since the Xorg configuration is embedded in the log-in manager's
13880 configuration---e.g., @code{gdm-configuration}---this procedure provides a
13881 shorthand to set the Xorg configuration.
13884 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
13885 Return a @code{startx} script in which the modules, fonts, etc. specified
13886 in @var{config}, are available. The result should be used in place of
13889 Usually the X server is started by a login manager.
13893 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
13894 Add @var{package}, a package for a screen locker or screen saver whose
13895 command is @var{program}, to the set of setuid programs and add a PAM entry
13896 for it. For example:
13899 (screen-locker-service xlockmore "xlock")
13902 makes the good ol' XlockMore usable.
13906 @node Printing Services
13907 @subsection Printing Services
13909 @cindex printer support with CUPS
13910 The @code{(gnu services cups)} module provides a Guix service definition
13911 for the CUPS printing service. To add printer support to a Guix
13912 system, add a @code{cups-service} to the operating system definition:
13914 @deffn {Scheme Variable} cups-service-type
13915 The service type for the CUPS print server. Its value should be a valid
13916 CUPS configuration (see below). To use the default settings, simply
13919 (service cups-service-type)
13923 The CUPS configuration controls the basic things about your CUPS
13924 installation: what interfaces it listens on, what to do if a print job
13925 fails, how much logging to do, and so on. To actually add a printer,
13926 you have to visit the @url{http://localhost:631} URL, or use a tool such
13927 as GNOME's printer configuration services. By default, configuring a
13928 CUPS service will generate a self-signed certificate if needed, for
13929 secure connections to the print server.
13931 Suppose you want to enable the Web interface of CUPS and also add
13932 support for Epson printers @i{via} the @code{escpr} package and for HP
13933 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
13934 like this (you need to use the @code{(gnu packages cups)} module):
13937 (service cups-service-type
13938 (cups-configuration
13939 (web-interface? #t)
13941 (list cups-filters escpr hplip-minimal))))
13944 Note: If you wish to use the Qt5 based GUI which comes with the hplip
13945 package then it is suggested that you install the @code{hplip} package,
13946 either in your OS configuration file or as your user.
13948 The available configuration parameters follow. Each parameter
13949 definition is preceded by its type; for example, @samp{string-list foo}
13950 indicates that the @code{foo} parameter should be specified as a list of
13951 strings. There is also a way to specify the configuration as a string,
13952 if you have an old @code{cupsd.conf} file that you want to port over
13953 from some other system; see the end for more details.
13955 @c The following documentation was initially generated by
13956 @c (generate-documentation) in (gnu services cups). Manually maintained
13957 @c documentation is better, so we shouldn't hesitate to edit below as
13958 @c needed. However if the change you want to make to this documentation
13959 @c can be done in an automated way, it's probably easier to change
13960 @c (generate-documentation) than to make it below and have to deal with
13961 @c the churn as CUPS updates.
13964 Available @code{cups-configuration} fields are:
13966 @deftypevr {@code{cups-configuration} parameter} package cups
13970 @deftypevr {@code{cups-configuration} parameter} package-list extensions
13971 Drivers and other extensions to the CUPS package.
13974 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
13975 Configuration of where to write logs, what directories to use for print
13976 spools, and related privileged configuration parameters.
13978 Available @code{files-configuration} fields are:
13980 @deftypevr {@code{files-configuration} parameter} log-location access-log
13981 Defines the access log filename. Specifying a blank filename disables
13982 access log generation. The value @code{stderr} causes log entries to be
13983 sent to the standard error file when the scheduler is running in the
13984 foreground, or to the system log daemon when run in the background. The
13985 value @code{syslog} causes log entries to be sent to the system log
13986 daemon. The server name may be included in filenames using the string
13987 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
13989 Defaults to @samp{"/var/log/cups/access_log"}.
13992 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
13993 Where CUPS should cache data.
13995 Defaults to @samp{"/var/cache/cups"}.
13998 @deftypevr {@code{files-configuration} parameter} string config-file-perm
13999 Specifies the permissions for all configuration files that the scheduler
14002 Note that the permissions for the printers.conf file are currently
14003 masked to only allow access from the scheduler user (typically root).
14004 This is done because printer device URIs sometimes contain sensitive
14005 authentication information that should not be generally known on the
14006 system. There is no way to disable this security feature.
14008 Defaults to @samp{"0640"}.
14011 @deftypevr {@code{files-configuration} parameter} log-location error-log
14012 Defines the error log filename. Specifying a blank filename disables
14013 error log generation. The value @code{stderr} causes log entries to be
14014 sent to the standard error file when the scheduler is running in the
14015 foreground, or to the system log daemon when run in the background. The
14016 value @code{syslog} causes log entries to be sent to the system log
14017 daemon. The server name may be included in filenames using the string
14018 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
14020 Defaults to @samp{"/var/log/cups/error_log"}.
14023 @deftypevr {@code{files-configuration} parameter} string fatal-errors
14024 Specifies which errors are fatal, causing the scheduler to exit. The
14029 No errors are fatal.
14032 All of the errors below are fatal.
14035 Browsing initialization errors are fatal, for example failed connections
14036 to the DNS-SD daemon.
14039 Configuration file syntax errors are fatal.
14042 Listen or Port errors are fatal, except for IPv6 failures on the
14043 loopback or @code{any} addresses.
14046 Log file creation or write errors are fatal.
14049 Bad startup file permissions are fatal, for example shared TLS
14050 certificate and key files with world-read permissions.
14053 Defaults to @samp{"all -browse"}.
14056 @deftypevr {@code{files-configuration} parameter} boolean file-device?
14057 Specifies whether the file pseudo-device can be used for new printer
14058 queues. The URI @uref{file:///dev/null} is always allowed.
14060 Defaults to @samp{#f}.
14063 @deftypevr {@code{files-configuration} parameter} string group
14064 Specifies the group name or ID that will be used when executing external
14067 Defaults to @samp{"lp"}.
14070 @deftypevr {@code{files-configuration} parameter} string log-file-perm
14071 Specifies the permissions for all log files that the scheduler writes.
14073 Defaults to @samp{"0644"}.
14076 @deftypevr {@code{files-configuration} parameter} log-location page-log
14077 Defines the page log filename. Specifying a blank filename disables
14078 page log generation. The value @code{stderr} causes log entries to be
14079 sent to the standard error file when the scheduler is running in the
14080 foreground, or to the system log daemon when run in the background. The
14081 value @code{syslog} causes log entries to be sent to the system log
14082 daemon. The server name may be included in filenames using the string
14083 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
14085 Defaults to @samp{"/var/log/cups/page_log"}.
14088 @deftypevr {@code{files-configuration} parameter} string remote-root
14089 Specifies the username that is associated with unauthenticated accesses
14090 by clients claiming to be the root user. The default is @code{remroot}.
14092 Defaults to @samp{"remroot"}.
14095 @deftypevr {@code{files-configuration} parameter} file-name request-root
14096 Specifies the directory that contains print jobs and other HTTP request
14099 Defaults to @samp{"/var/spool/cups"}.
14102 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
14103 Specifies the level of security sandboxing that is applied to print
14104 filters, backends, and other child processes of the scheduler; either
14105 @code{relaxed} or @code{strict}. This directive is currently only
14106 used/supported on macOS.
14108 Defaults to @samp{strict}.
14111 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
14112 Specifies the location of TLS certificates and private keys. CUPS will
14113 look for public and private keys in this directory: a @code{.crt} files
14114 for PEM-encoded certificates and corresponding @code{.key} files for
14115 PEM-encoded private keys.
14117 Defaults to @samp{"/etc/cups/ssl"}.
14120 @deftypevr {@code{files-configuration} parameter} file-name server-root
14121 Specifies the directory containing the server configuration files.
14123 Defaults to @samp{"/etc/cups"}.
14126 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
14127 Specifies whether the scheduler calls fsync(2) after writing
14128 configuration or state files.
14130 Defaults to @samp{#f}.
14133 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
14134 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
14137 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
14138 Specifies the directory where temporary files are stored.
14140 Defaults to @samp{"/var/spool/cups/tmp"}.
14143 @deftypevr {@code{files-configuration} parameter} string user
14144 Specifies the user name or ID that is used when running external
14147 Defaults to @samp{"lp"}.
14151 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
14152 Specifies the logging level for the AccessLog file. The @code{config}
14153 level logs when printers and classes are added, deleted, or modified and
14154 when configuration files are accessed or updated. The @code{actions}
14155 level logs when print jobs are submitted, held, released, modified, or
14156 canceled, and any of the conditions for @code{config}. The @code{all}
14157 level logs all requests.
14159 Defaults to @samp{actions}.
14162 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
14163 Specifies whether to purge job history data automatically when it is no
14164 longer required for quotas.
14166 Defaults to @samp{#f}.
14169 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
14170 Specifies which protocols to use for local printer sharing.
14172 Defaults to @samp{dnssd}.
14175 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
14176 Specifies whether the CUPS web interface is advertised.
14178 Defaults to @samp{#f}.
14181 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
14182 Specifies whether shared printers are advertised.
14184 Defaults to @samp{#f}.
14187 @deftypevr {@code{cups-configuration} parameter} string classification
14188 Specifies the security classification of the server. Any valid banner
14189 name can be used, including "classified", "confidential", "secret",
14190 "topsecret", and "unclassified", or the banner can be omitted to disable
14191 secure printing functions.
14193 Defaults to @samp{""}.
14196 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
14197 Specifies whether users may override the classification (cover page) of
14198 individual print jobs using the @code{job-sheets} option.
14200 Defaults to @samp{#f}.
14203 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
14204 Specifies the default type of authentication to use.
14206 Defaults to @samp{Basic}.
14209 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
14210 Specifies whether encryption will be used for authenticated requests.
14212 Defaults to @samp{Required}.
14215 @deftypevr {@code{cups-configuration} parameter} string default-language
14216 Specifies the default language to use for text and web content.
14218 Defaults to @samp{"en"}.
14221 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
14222 Specifies the default paper size for new print queues. @samp{"Auto"}
14223 uses a locale-specific default, while @samp{"None"} specifies there is
14224 no default paper size. Specific size names are typically
14225 @samp{"Letter"} or @samp{"A4"}.
14227 Defaults to @samp{"Auto"}.
14230 @deftypevr {@code{cups-configuration} parameter} string default-policy
14231 Specifies the default access policy to use.
14233 Defaults to @samp{"default"}.
14236 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
14237 Specifies whether local printers are shared by default.
14239 Defaults to @samp{#t}.
14242 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
14243 Specifies the delay for updating of configuration and state files, in
14244 seconds. A value of 0 causes the update to happen as soon as possible,
14245 typically within a few milliseconds.
14247 Defaults to @samp{30}.
14250 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
14251 Specifies what to do when an error occurs. Possible values are
14252 @code{abort-job}, which will discard the failed print job;
14253 @code{retry-job}, which will retry the job at a later time;
14254 @code{retry-this-job}, which retries the failed job immediately; and
14255 @code{stop-printer}, which stops the printer.
14257 Defaults to @samp{stop-printer}.
14260 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
14261 Specifies the maximum cost of filters that are run concurrently, which
14262 can be used to minimize disk, memory, and CPU resource problems. A
14263 limit of 0 disables filter limiting. An average print to a
14264 non-PostScript printer needs a filter limit of about 200. A PostScript
14265 printer needs about half that (100). Setting the limit below these
14266 thresholds will effectively limit the scheduler to printing a single job
14269 Defaults to @samp{0}.
14272 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
14273 Specifies the scheduling priority of filters that are run to print a
14274 job. The nice value ranges from 0, the highest priority, to 19, the
14277 Defaults to @samp{0}.
14280 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
14281 Specifies whether to do reverse lookups on connecting clients. The
14282 @code{double} setting causes @code{cupsd} to verify that the hostname
14283 resolved from the address matches one of the addresses returned for that
14284 hostname. Double lookups also prevent clients with unregistered
14285 addresses from connecting to your server. Only set this option to
14286 @code{#t} or @code{double} if absolutely required.
14288 Defaults to @samp{#f}.
14291 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
14292 Specifies the number of seconds to wait before killing the filters and
14293 backend associated with a canceled or held job.
14295 Defaults to @samp{30}.
14298 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
14299 Specifies the interval between retries of jobs in seconds. This is
14300 typically used for fax queues but can also be used with normal print
14301 queues whose error policy is @code{retry-job} or
14302 @code{retry-current-job}.
14304 Defaults to @samp{30}.
14307 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
14308 Specifies the number of retries that are done for jobs. This is
14309 typically used for fax queues but can also be used with normal print
14310 queues whose error policy is @code{retry-job} or
14311 @code{retry-current-job}.
14313 Defaults to @samp{5}.
14316 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
14317 Specifies whether to support HTTP keep-alive connections.
14319 Defaults to @samp{#t}.
14322 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
14323 Specifies how long an idle client connection remains open, in seconds.
14325 Defaults to @samp{30}.
14328 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
14329 Specifies the maximum size of print files, IPP requests, and HTML form
14330 data. A limit of 0 disables the limit check.
14332 Defaults to @samp{0}.
14335 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
14336 Listens on the specified interfaces for connections. Valid values are
14337 of the form @var{address}:@var{port}, where @var{address} is either an
14338 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
14339 indicate all addresses. Values can also be file names of local UNIX
14340 domain sockets. The Listen directive is similar to the Port directive
14341 but allows you to restrict access to specific interfaces or networks.
14344 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
14345 Specifies the number of pending connections that will be allowed. This
14346 normally only affects very busy servers that have reached the MaxClients
14347 limit, but can also be triggered by large numbers of simultaneous
14348 connections. When the limit is reached, the operating system will
14349 refuse additional connections until the scheduler can accept the pending
14352 Defaults to @samp{128}.
14355 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
14356 Specifies a set of additional access controls.
14358 Available @code{location-access-controls} fields are:
14360 @deftypevr {@code{location-access-controls} parameter} file-name path
14361 Specifies the URI path to which the access control applies.
14364 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
14365 Access controls for all access to this path, in the same format as the
14366 @code{access-controls} of @code{operation-access-control}.
14368 Defaults to @samp{()}.
14371 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
14372 Access controls for method-specific access to this path.
14374 Defaults to @samp{()}.
14376 Available @code{method-access-controls} fields are:
14378 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
14379 If @code{#t}, apply access controls to all methods except the listed
14380 methods. Otherwise apply to only the listed methods.
14382 Defaults to @samp{#f}.
14385 @deftypevr {@code{method-access-controls} parameter} method-list methods
14386 Methods to which this access control applies.
14388 Defaults to @samp{()}.
14391 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
14392 Access control directives, as a list of strings. Each string should be
14393 one directive, such as "Order allow,deny".
14395 Defaults to @samp{()}.
14400 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
14401 Specifies the number of debugging messages that are retained for logging
14402 if an error occurs in a print job. Debug messages are logged regardless
14403 of the LogLevel setting.
14405 Defaults to @samp{100}.
14408 @deftypevr {@code{cups-configuration} parameter} log-level log-level
14409 Specifies the level of logging for the ErrorLog file. The value
14410 @code{none} stops all logging while @code{debug2} logs everything.
14412 Defaults to @samp{info}.
14415 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
14416 Specifies the format of the date and time in the log files. The value
14417 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
14419 Defaults to @samp{standard}.
14422 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
14423 Specifies the maximum number of simultaneous clients that are allowed by
14426 Defaults to @samp{100}.
14429 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
14430 Specifies the maximum number of simultaneous clients that are allowed
14431 from a single address.
14433 Defaults to @samp{100}.
14436 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
14437 Specifies the maximum number of copies that a user can print of each
14440 Defaults to @samp{9999}.
14443 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
14444 Specifies the maximum time a job may remain in the @code{indefinite}
14445 hold state before it is canceled. A value of 0 disables cancellation of
14448 Defaults to @samp{0}.
14451 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
14452 Specifies the maximum number of simultaneous jobs that are allowed. Set
14453 to 0 to allow an unlimited number of jobs.
14455 Defaults to @samp{500}.
14458 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
14459 Specifies the maximum number of simultaneous jobs that are allowed per
14460 printer. A value of 0 allows up to MaxJobs jobs per printer.
14462 Defaults to @samp{0}.
14465 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
14466 Specifies the maximum number of simultaneous jobs that are allowed per
14467 user. A value of 0 allows up to MaxJobs jobs per user.
14469 Defaults to @samp{0}.
14472 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
14473 Specifies the maximum time a job may take to print before it is
14474 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
14476 Defaults to @samp{10800}.
14479 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
14480 Specifies the maximum size of the log files before they are rotated, in
14481 bytes. The value 0 disables log rotation.
14483 Defaults to @samp{1048576}.
14486 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
14487 Specifies the maximum amount of time to allow between files in a
14488 multiple file print job, in seconds.
14490 Defaults to @samp{300}.
14493 @deftypevr {@code{cups-configuration} parameter} string page-log-format
14494 Specifies the format of PageLog lines. Sequences beginning with percent
14495 (@samp{%}) characters are replaced with the corresponding information,
14496 while all other characters are copied literally. The following percent
14497 sequences are recognized:
14501 insert a single percent character
14504 insert the value of the specified IPP attribute
14507 insert the number of copies for the current page
14510 insert the current page number
14513 insert the current date and time in common log format
14519 insert the printer name
14522 insert the username
14525 A value of the empty string disables page logging. The string @code{%p
14526 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
14527 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
14530 Defaults to @samp{""}.
14533 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
14534 Passes the specified environment variable(s) to child processes; a list
14537 Defaults to @samp{()}.
14540 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
14541 Specifies named access control policies.
14543 Available @code{policy-configuration} fields are:
14545 @deftypevr {@code{policy-configuration} parameter} string name
14546 Name of the policy.
14549 @deftypevr {@code{policy-configuration} parameter} string job-private-access
14550 Specifies an access list for a job's private values. @code{@@ACL} maps
14551 to the printer's requesting-user-name-allowed or
14552 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14553 owner. @code{@@SYSTEM} maps to the groups listed for the
14554 @code{system-group} field of the @code{files-config} configuration,
14555 which is reified into the @code{cups-files.conf(5)} file. Other
14556 possible elements of the access list include specific user names, and
14557 @code{@@@var{group}} to indicate members of a specific group. The
14558 access list may also be simply @code{all} or @code{default}.
14560 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14563 @deftypevr {@code{policy-configuration} parameter} string job-private-values
14564 Specifies the list of job values to make private, or @code{all},
14565 @code{default}, or @code{none}.
14567 Defaults to @samp{"job-name job-originating-host-name
14568 job-originating-user-name phone"}.
14571 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
14572 Specifies an access list for a subscription's private values.
14573 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
14574 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
14575 owner. @code{@@SYSTEM} maps to the groups listed for the
14576 @code{system-group} field of the @code{files-config} configuration,
14577 which is reified into the @code{cups-files.conf(5)} file. Other
14578 possible elements of the access list include specific user names, and
14579 @code{@@@var{group}} to indicate members of a specific group. The
14580 access list may also be simply @code{all} or @code{default}.
14582 Defaults to @samp{"@@OWNER @@SYSTEM"}.
14585 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
14586 Specifies the list of job values to make private, or @code{all},
14587 @code{default}, or @code{none}.
14589 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
14590 notify-subscriber-user-name notify-user-data"}.
14593 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
14594 Access control by IPP operation.
14596 Defaults to @samp{()}.
14600 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
14601 Specifies whether job files (documents) are preserved after a job is
14602 printed. If a numeric value is specified, job files are preserved for
14603 the indicated number of seconds after printing. Otherwise a boolean
14604 value applies indefinitely.
14606 Defaults to @samp{86400}.
14609 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
14610 Specifies whether the job history is preserved after a job is printed.
14611 If a numeric value is specified, the job history is preserved for the
14612 indicated number of seconds after printing. If @code{#t}, the job
14613 history is preserved until the MaxJobs limit is reached.
14615 Defaults to @samp{#t}.
14618 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
14619 Specifies the amount of time to wait for job completion before
14620 restarting the scheduler.
14622 Defaults to @samp{30}.
14625 @deftypevr {@code{cups-configuration} parameter} string rip-cache
14626 Specifies the maximum amount of memory to use when converting documents
14627 into bitmaps for a printer.
14629 Defaults to @samp{"128m"}.
14632 @deftypevr {@code{cups-configuration} parameter} string server-admin
14633 Specifies the email address of the server administrator.
14635 Defaults to @samp{"root@@localhost.localdomain"}.
14638 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
14639 The ServerAlias directive is used for HTTP Host header validation when
14640 clients connect to the scheduler from external interfaces. Using the
14641 special name @code{*} can expose your system to known browser-based DNS
14642 rebinding attacks, even when accessing sites through a firewall. If the
14643 auto-discovery of alternate names does not work, we recommend listing
14644 each alternate name with a ServerAlias directive instead of using
14647 Defaults to @samp{*}.
14650 @deftypevr {@code{cups-configuration} parameter} string server-name
14651 Specifies the fully-qualified host name of the server.
14653 Defaults to @samp{"localhost"}.
14656 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
14657 Specifies what information is included in the Server header of HTTP
14658 responses. @code{None} disables the Server header. @code{ProductOnly}
14659 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
14660 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
14661 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
14662 the output of the @code{uname} command. @code{Full} reports @code{CUPS
14663 2.0.0 (@var{uname}) IPP/2.0}.
14665 Defaults to @samp{Minimal}.
14668 @deftypevr {@code{cups-configuration} parameter} string set-env
14669 Set the specified environment variable to be passed to child processes.
14671 Defaults to @samp{"variable value"}.
14674 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
14675 Listens on the specified interfaces for encrypted connections. Valid
14676 values are of the form @var{address}:@var{port}, where @var{address} is
14677 either an IPv6 address enclosed in brackets, an IPv4 address, or
14678 @code{*} to indicate all addresses.
14680 Defaults to @samp{()}.
14683 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
14684 Sets encryption options. By default, CUPS only supports encryption
14685 using TLS v1.0 or higher using known secure cipher suites. The
14686 @code{AllowRC4} option enables the 128-bit RC4 cipher suites, which are
14687 required for some older clients that do not implement newer ones. The
14688 @code{AllowSSL3} option enables SSL v3.0, which is required for some
14689 older clients that do not support TLS v1.0.
14691 Defaults to @samp{()}.
14694 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
14695 Specifies whether the scheduler requires clients to strictly adhere to
14696 the IPP specifications.
14698 Defaults to @samp{#f}.
14701 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
14702 Specifies the HTTP request timeout, in seconds.
14704 Defaults to @samp{300}.
14708 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
14709 Specifies whether the web interface is enabled.
14711 Defaults to @samp{#f}.
14714 At this point you're probably thinking ``oh dear, Guix manual, I like
14715 you but you can stop already with the configuration options''. Indeed.
14716 However, one more point: it could be that you have an existing
14717 @code{cupsd.conf} that you want to use. In that case, you can pass an
14718 @code{opaque-cups-configuration} as the configuration of a
14719 @code{cups-service-type}.
14721 Available @code{opaque-cups-configuration} fields are:
14723 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
14727 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
14728 The contents of the @code{cupsd.conf}, as a string.
14731 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
14732 The contents of the @code{cups-files.conf} file, as a string.
14735 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
14736 strings of the same name, you could instantiate a CUPS service like
14740 (service cups-service-type
14741 (opaque-cups-configuration
14742 (cupsd.conf cupsd.conf)
14743 (cups-files.conf cups-files.conf)))
14747 @node Desktop Services
14748 @subsection Desktop Services
14750 The @code{(gnu services desktop)} module provides services that are
14751 usually useful in the context of a ``desktop'' setup---that is, on a
14752 machine running a graphical display server, possibly with graphical user
14753 interfaces, etc. It also defines services that provide specific desktop
14754 environments like GNOME, Xfce or MATE.
14756 To simplify things, the module defines a variable containing the set of
14757 services that users typically expect on a machine with a graphical
14758 environment and networking:
14760 @defvr {Scheme Variable} %desktop-services
14761 This is a list of services that builds upon @code{%base-services} and
14762 adds or adjusts services for a typical ``desktop'' setup.
14764 In particular, it adds a graphical login manager (@pxref{X Window,
14765 @code{gdm-service-type}}), screen lockers, a network management tool
14766 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
14767 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
14768 energy and color management services, the @code{elogind} login and seat
14769 manager, the Polkit privilege service, the GeoClue location service, the
14770 AccountsService daemon that allows authorized users change system passwords,
14771 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
14772 name service switch service configured to be able to use @code{nss-mdns}
14773 (@pxref{Name Service Switch, mDNS}).
14776 The @code{%desktop-services} variable can be used as the @code{services}
14777 field of an @code{operating-system} declaration (@pxref{operating-system
14778 Reference, @code{services}}).
14780 Additionally, the @code{gnome-desktop-service-type},
14781 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
14782 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
14783 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
14784 services like the backlight adjustment helpers and the power management
14785 utilities are added to the system, extending @code{polkit} and @code{dbus}
14786 appropriately, allowing GNOME to operate with elevated privileges on a
14787 limited number of special-purpose system interfaces. Additionally,
14788 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
14789 metapackage to the system profile. Likewise, adding the Xfce service
14790 not only adds the @code{xfce} metapackage to the system profile, but it
14791 also gives the Thunar file manager the ability to open a ``root-mode''
14792 file management window, if the user authenticates using the
14793 administrator's password via the standard polkit graphical interface.
14794 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
14795 appropriately, allowing MATE to operate with elevated privileges on a
14796 limited number of special-purpose system interfaces. Additionally,
14797 adding a service of type @code{mate-desktop-service-type} adds the MATE
14798 metapackage to the system profile. ``Adding Enlightenment'' means that
14799 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
14800 are set as setuid, allowing Enlightenment's screen locker and other
14801 functionality to work as expetected.
14803 The desktop environments in Guix use the Xorg display server by
14804 default. If you'd like to use the newer display server protocol
14805 called Wayland, you need to use the @code{sddm-service} instead of
14806 GDM as the graphical login manager. You should then
14807 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
14808 also try starting GNOME on Wayland manually from a TTY with the
14809 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
14810 gnome-session``. Currently only GNOME has support for Wayland.
14812 @defvr {Scheme Variable} gnome-desktop-service-type
14813 This is the type of the service that adds the @uref{https://www.gnome.org,
14814 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
14815 object (see below.)
14817 This service adds the @code{gnome} package to the system profile, and extends
14818 polkit with the actions from @code{gnome-settings-daemon}.
14821 @deftp {Data Type} gnome-desktop-configuration
14822 Configuration record for the GNOME desktop environment.
14825 @item @code{gnome} (default: @code{gnome})
14826 The GNOME package to use.
14830 @defvr {Scheme Variable} xfce-desktop-service-type
14831 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
14832 desktop environment. Its value is an @code{xfce-desktop-configuration} object
14835 This service adds the @code{xfce} package to the system profile, and
14836 extends polkit with the ability for @code{thunar} to manipulate the file
14837 system as root from within a user session, after the user has authenticated
14838 with the administrator's password.
14841 @deftp {Data Type} xfce-desktop-configuration
14842 Configuration record for the Xfce desktop environment.
14845 @item @code{xfce} (default: @code{xfce})
14846 The Xfce package to use.
14850 @deffn {Scheme Variable} mate-desktop-service-type
14851 This is the type of the service that runs the @uref{https://mate-desktop.org/,
14852 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
14853 object (see below.)
14855 This service adds the @code{mate} package to the system
14856 profile, and extends polkit with the actions from
14857 @code{mate-settings-daemon}.
14860 @deftp {Data Type} mate-desktop-configuration
14861 Configuration record for the MATE desktop environment.
14864 @item @code{mate} (default: @code{mate})
14865 The MATE package to use.
14869 @deffn {Scheme Variable} enlightenment-desktop-service-type
14870 Return a service that adds the @code{enlightenment} package to the system
14871 profile, and extends dbus with actions from @code{efl}.
14874 @deftp {Data Type} enlightenment-desktop-service-configuration
14876 @item @code{enlightenment} (default: @code{enlightenment})
14877 The enlightenment package to use.
14881 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
14882 the default @code{%desktop-services} variable doesn't include any of
14883 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
14884 @code{%desktop-services} in the @code{services} field of your
14885 @code{operating-system}:
14888 (use-modules (gnu))
14889 (use-service-modules desktop)
14892 ;; cons* adds items to the list given as its last argument.
14893 (services (cons* (service gnome-desktop-service-type)
14894 (service xfce-desktop-service)
14895 %desktop-services))
14899 These desktop environments will then be available as options in the
14900 graphical login window.
14902 The actual service definitions included in @code{%desktop-services} and
14903 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
14904 are described below.
14906 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
14907 Return a service that runs the ``system bus'', using @var{dbus}, with
14908 support for @var{services}.
14910 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
14911 facility. Its system bus is used to allow system services to communicate
14912 and to be notified of system-wide events.
14914 @var{services} must be a list of packages that provide an
14915 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
14916 and policy files. For example, to allow avahi-daemon to use the system bus,
14917 @var{services} must be equal to @code{(list avahi)}.
14920 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
14921 Return a service that runs the @code{elogind} login and
14922 seat management daemon. @uref{https://github.com/elogind/elogind,
14923 Elogind} exposes a D-Bus interface that can be used to know which users
14924 are logged in, know what kind of sessions they have open, suspend the
14925 system, inhibit system suspend, reboot the system, and other tasks.
14927 Elogind handles most system-level power events for a computer, for
14928 example suspending the system when a lid is closed, or shutting it down
14929 when the power button is pressed.
14931 The @var{config} keyword argument specifies the configuration for
14932 elogind, and should be the result of an @code{(elogind-configuration
14933 (@var{parameter} @var{value})...)} invocation. Available parameters and
14934 their default values are:
14937 @item kill-user-processes?
14939 @item kill-only-users
14941 @item kill-exclude-users
14943 @item inhibit-delay-max-seconds
14945 @item handle-power-key
14947 @item handle-suspend-key
14949 @item handle-hibernate-key
14951 @item handle-lid-switch
14953 @item handle-lid-switch-docked
14955 @item power-key-ignore-inhibited?
14957 @item suspend-key-ignore-inhibited?
14959 @item hibernate-key-ignore-inhibited?
14961 @item lid-switch-ignore-inhibited?
14963 @item holdoff-timeout-seconds
14967 @item idle-action-seconds
14969 @item runtime-directory-size-percent
14971 @item runtime-directory-size
14975 @item suspend-state
14976 @code{("mem" "standby" "freeze")}
14979 @item hibernate-state
14981 @item hibernate-mode
14982 @code{("platform" "shutdown")}
14983 @item hybrid-sleep-state
14985 @item hybrid-sleep-mode
14986 @code{("suspend" "platform" "shutdown")}
14990 @deffn {Scheme Procedure} accountsservice-service @
14991 [#:accountsservice @var{accountsservice}]
14992 Return a service that runs AccountsService, a system service that can
14993 list available accounts, change their passwords, and so on.
14994 AccountsService integrates with PolicyKit to enable unprivileged users
14995 to acquire the capability to modify their system configuration.
14996 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
14997 accountsservice web site} for more information.
14999 The @var{accountsservice} keyword argument is the @code{accountsservice}
15000 package to expose as a service.
15003 @deffn {Scheme Procedure} polkit-service @
15004 [#:polkit @var{polkit}]
15005 Return a service that runs the
15006 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
15007 management service}, which allows system administrators to grant access to
15008 privileged operations in a structured way. By querying the Polkit service, a
15009 privileged system component can know when it should grant additional
15010 capabilities to ordinary users. For example, an ordinary user can be granted
15011 the capability to suspend the system if the user is logged in locally.
15014 @defvr {Scheme Variable} upower-service-type
15015 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
15016 system-wide monitor for power consumption and battery levels, with the given
15017 configuration settings.
15019 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
15020 notably used by GNOME.
15023 @deftp {Data Type} upower-configuration
15024 Data type representation the configuration for UPower.
15028 @item @code{upower} (default: @var{upower})
15029 Package to use for @code{upower}.
15031 @item @code{watts-up-pro?} (default: @code{#f})
15032 Enable the Watts Up Pro device.
15034 @item @code{poll-batteries?} (default: @code{#t})
15035 Enable polling the kernel for battery level changes.
15037 @item @code{ignore-lid?} (default: @code{#f})
15038 Ignore the lid state, this can be useful if it's incorrect on a device.
15040 @item @code{use-percentage-for-policy?} (default: @code{#f})
15041 Whether battery percentage based policy should be used. The default is to use
15042 the time left, change to @code{#t} to use the percentage.
15044 @item @code{percentage-low} (default: @code{10})
15045 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15046 at which the battery is considered low.
15048 @item @code{percentage-critical} (default: @code{3})
15049 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15050 at which the battery is considered critical.
15052 @item @code{percentage-action} (default: @code{2})
15053 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15054 at which action will be taken.
15056 @item @code{time-low} (default: @code{1200})
15057 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15058 seconds at which the battery is considered low.
15060 @item @code{time-critical} (default: @code{300})
15061 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15062 seconds at which the battery is considered critical.
15064 @item @code{time-action} (default: @code{120})
15065 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15066 seconds at which action will be taken.
15068 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
15069 The action taken when @code{percentage-action} or @code{time-action} is
15070 reached (depending on the configuration of @code{use-percentage-for-policy?}).
15072 Possible values are:
15082 @code{'hybrid-sleep}.
15088 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
15089 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
15090 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
15091 notifications and ways to mount/unmount disks. Programs that talk to UDisks
15092 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
15095 @deffn {Scheme Procedure} colord-service [#:colord @var{colord}]
15096 Return a service that runs @command{colord}, a system service with a D-Bus
15097 interface to manage the color profiles of input and output devices such as
15098 screens and scanners. It is notably used by the GNOME Color Manager graphical
15099 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
15100 site} for more information.
15103 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
15104 Return a configuration allowing an application to access GeoClue
15105 location data. @var{name} is the Desktop ID of the application, without
15106 the @code{.desktop} part. If @var{allowed?} is true, the application
15107 will have access to location information by default. The boolean
15108 @var{system?} value indicates whether an application is a system component
15109 or not. Finally @var{users} is a list of UIDs of all users for which
15110 this application is allowed location info access. An empty users list
15111 means that all users are allowed.
15114 @defvr {Scheme Variable} %standard-geoclue-applications
15115 The standard list of well-known GeoClue application configurations,
15116 granting authority to the GNOME date-and-time utility to ask for the
15117 current location in order to set the time zone, and allowing the
15118 IceCat and Epiphany web browsers to request location information.
15119 IceCat and Epiphany both query the user before allowing a web page to
15120 know the user's location.
15123 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
15124 [#:whitelist '()] @
15125 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
15126 [#:submit-data? #f]
15127 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
15128 [#:submission-nick "geoclue"] @
15129 [#:applications %standard-geoclue-applications]
15130 Return a service that runs the GeoClue location service. This service
15131 provides a D-Bus interface to allow applications to request access to a
15132 user's physical location, and optionally to add information to online
15133 location databases. See
15134 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
15135 web site} for more information.
15138 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
15139 [@w{#:auto-enable? #f}]
15140 Return a service that runs the @command{bluetoothd} daemon, which
15141 manages all the Bluetooth devices and provides a number of D-Bus
15142 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
15143 powered automatically at boot, which can be useful when using a
15144 bluetooth keyboard or mouse.
15146 Users need to be in the @code{lp} group to access the D-Bus service.
15149 @node Sound Services
15150 @subsection Sound Services
15152 @cindex sound support
15154 @cindex PulseAudio, sound support
15156 The @code{(gnu services sound)} module provides a service to configure the
15157 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
15158 preferred ALSA output driver.
15160 @deffn {Scheme Variable} alsa-service-type
15161 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
15162 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
15163 configuration file. The value for this type is a @command{alsa-configuration}
15164 record as in this example:
15167 (service alsa-service-type)
15170 See below for details about @code{alsa-configuration}.
15173 @deftp {Data Type} alsa-configuration
15174 Data type representing the configuration for @code{alsa-service}.
15177 @item @code{alsa-plugins} (default: @var{alsa-plugins})
15178 @code{alsa-plugins} package to use.
15180 @item @code{pulseaudio?} (default: @var{#t})
15181 Whether ALSA applications should transparently be made to use the
15182 @uref{http://www.pulseaudio.org/, PulseAudio} sound server.
15184 Using PulseAudio allows you to run several sound-producing applications
15185 at the same time and to individual control them @i{via}
15186 @command{pavucontrol}, among other things.
15188 @item @code{extra-options} (default: @var{""})
15189 String to append to the @file{/etc/asound.conf} file.
15194 Individual users who want to override the system configuration of ALSA can do
15195 it with the @file{~/.asoundrc} file:
15198 # In guix, we have to specify the absolute path for plugins.
15200 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
15203 # Routing ALSA to jack:
15204 # <http://jackaudio.org/faq/routing_alsa.html>.
15208 0 system:playback_1
15209 1 system:playback_2
15226 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
15230 @node Database Services
15231 @subsection Database Services
15235 The @code{(gnu services databases)} module provides the following services.
15237 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
15238 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
15239 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
15240 Return a service that runs @var{postgresql}, the PostgreSQL database
15243 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
15244 creates a database cluster with @var{locale} as the default
15245 locale, stored in @var{data-directory}. It then listens on @var{port}.
15247 @cindex postgresql extension-packages
15248 Additional extensions are loaded from packages listed in
15249 @var{extension-packages}. Extensions are available at runtime. For instance,
15250 to create a geographic database using the @code{postgis} extension, a user can
15251 configure the postgresql-service as in this example:
15255 (use-package-modules databases geo)
15259 ;; postgresql is required to run `psql' but postgis is not required for
15260 ;; proper operation.
15261 (packages (cons* postgresql %base-packages))
15264 (postgresql-service #:extension-packages (list postgis))
15268 Then the extension becomes visible and you can initialise an empty geographic
15269 database in this way:
15273 > create database postgistest;
15274 > \connect postgistest;
15275 > create extension postgis;
15276 > create extension postgis_topology;
15279 There is no need to add this field for contrib extensions such as hstore or
15280 dblink as they are already loadable by postgresql. This field is only
15281 required to add extensions provided by other packages.
15284 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
15285 Return a service that runs @command{mysqld}, the MySQL or MariaDB
15288 The optional @var{config} argument specifies the configuration for
15289 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
15292 @deftp {Data Type} mysql-configuration
15293 Data type representing the configuration of @var{mysql-service}.
15296 @item @code{mysql} (default: @var{mariadb})
15297 Package object of the MySQL database server, can be either @var{mariadb}
15300 For MySQL, a temporary root password will be displayed at activation time.
15301 For MariaDB, the root password is empty.
15303 @item @code{port} (default: @code{3306})
15304 TCP port on which the database server listens for incoming connections.
15308 @defvr {Scheme Variable} memcached-service-type
15309 This is the service type for the @uref{https://memcached.org/,
15310 Memcached} service, which provides a distributed in memory cache. The
15311 value for the service type is a @code{memcached-configuration} object.
15315 (service memcached-service-type)
15318 @deftp {Data Type} memcached-configuration
15319 Data type representing the configuration of memcached.
15322 @item @code{memcached} (default: @code{memcached})
15323 The Memcached package to use.
15325 @item @code{interfaces} (default: @code{'("0.0.0.0")})
15326 Network interfaces on which to listen.
15328 @item @code{tcp-port} (default: @code{11211})
15329 Port on which to accept connections on,
15331 @item @code{udp-port} (default: @code{11211})
15332 Port on which to accept UDP connections on, a value of 0 will disable
15333 listening on a UDP socket.
15335 @item @code{additional-options} (default: @code{'()})
15336 Additional command line options to pass to @code{memcached}.
15340 @defvr {Scheme Variable} mongodb-service-type
15341 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
15342 The value for the service type is a @code{mongodb-configuration} object.
15346 (service mongodb-service-type)
15349 @deftp {Data Type} mongodb-configuration
15350 Data type representing the configuration of mongodb.
15353 @item @code{mongodb} (default: @code{mongodb})
15354 The MongoDB package to use.
15356 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
15357 The configuration file for MongoDB.
15359 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
15360 This value is used to create the directory, so that it exists and is
15361 owned by the mongodb user. It should match the data-directory which
15362 MongoDB is configured to use through the configuration file.
15366 @defvr {Scheme Variable} redis-service-type
15367 This is the service type for the @uref{https://redis.io/, Redis}
15368 key/value store, whose value is a @code{redis-configuration} object.
15371 @deftp {Data Type} redis-configuration
15372 Data type representing the configuration of redis.
15375 @item @code{redis} (default: @code{redis})
15376 The Redis package to use.
15378 @item @code{bind} (default: @code{"127.0.0.1"})
15379 Network interface on which to listen.
15381 @item @code{port} (default: @code{6379})
15382 Port on which to accept connections on, a value of 0 will disable
15383 listening on a TCP socket.
15385 @item @code{working-directory} (default: @code{"/var/lib/redis"})
15386 Directory in which to store the database and related files.
15390 @node Mail Services
15391 @subsection Mail Services
15395 The @code{(gnu services mail)} module provides Guix service definitions
15396 for email services: IMAP, POP3, and LMTP servers, as well as mail
15397 transport agents (MTAs). Lots of acronyms! These services are detailed
15398 in the subsections below.
15400 @subsubheading Dovecot Service
15402 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
15403 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
15406 By default, Dovecot does not need much configuration; the default
15407 configuration object created by @code{(dovecot-configuration)} will
15408 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
15409 certificate will be generated for TLS-protected connections, though
15410 Dovecot will also listen on cleartext ports by default. There are a
15411 number of options, though, which mail administrators might need to change,
15412 and as is the case with other services, Guix allows the system
15413 administrator to specify these parameters via a uniform Scheme interface.
15415 For example, to specify that mail is located at @code{maildir~/.mail},
15416 one would instantiate the Dovecot service like this:
15419 (dovecot-service #:config
15420 (dovecot-configuration
15421 (mail-location "maildir:~/.mail")))
15424 The available configuration parameters follow. Each parameter
15425 definition is preceded by its type; for example, @samp{string-list foo}
15426 indicates that the @code{foo} parameter should be specified as a list of
15427 strings. There is also a way to specify the configuration as a string,
15428 if you have an old @code{dovecot.conf} file that you want to port over
15429 from some other system; see the end for more details.
15431 @c The following documentation was initially generated by
15432 @c (generate-documentation) in (gnu services mail). Manually maintained
15433 @c documentation is better, so we shouldn't hesitate to edit below as
15434 @c needed. However if the change you want to make to this documentation
15435 @c can be done in an automated way, it's probably easier to change
15436 @c (generate-documentation) than to make it below and have to deal with
15437 @c the churn as dovecot updates.
15439 Available @code{dovecot-configuration} fields are:
15441 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
15442 The dovecot package.
15445 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
15446 A list of IPs or hosts where to listen for connections. @samp{*}
15447 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
15448 interfaces. If you want to specify non-default ports or anything more
15449 complex, customize the address and port fields of the
15450 @samp{inet-listener} of the specific services you are interested in.
15453 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
15454 List of protocols we want to serve. Available protocols include
15455 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
15457 Available @code{protocol-configuration} fields are:
15459 @deftypevr {@code{protocol-configuration} parameter} string name
15460 The name of the protocol.
15463 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
15464 UNIX socket path to the master authentication server to find users.
15465 This is used by imap (for shared users) and lda.
15466 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
15469 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
15470 Space separated list of plugins to load.
15473 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
15474 Maximum number of IMAP connections allowed for a user from each IP
15475 address. NOTE: The username is compared case-sensitively.
15476 Defaults to @samp{10}.
15481 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
15482 List of services to enable. Available services include @samp{imap},
15483 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
15486 Available @code{service-configuration} fields are:
15488 @deftypevr {@code{service-configuration} parameter} string kind
15489 The service kind. Valid values include @code{director},
15490 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
15491 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
15492 @code{tcpwrap}, @code{quota-warning}, or anything else.
15495 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
15496 Listeners for the service. A listener is either a
15497 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
15498 an @code{inet-listener-configuration}.
15499 Defaults to @samp{()}.
15501 Available @code{unix-listener-configuration} fields are:
15503 @deftypevr {@code{unix-listener-configuration} parameter} string path
15504 Path to the file, relative to @code{base-dir} field. This is also used as
15508 @deftypevr {@code{unix-listener-configuration} parameter} string mode
15509 The access mode for the socket.
15510 Defaults to @samp{"0600"}.
15513 @deftypevr {@code{unix-listener-configuration} parameter} string user
15514 The user to own the socket.
15515 Defaults to @samp{""}.
15518 @deftypevr {@code{unix-listener-configuration} parameter} string group
15519 The group to own the socket.
15520 Defaults to @samp{""}.
15524 Available @code{fifo-listener-configuration} fields are:
15526 @deftypevr {@code{fifo-listener-configuration} parameter} string path
15527 Path to the file, relative to @code{base-dir} field. This is also used as
15531 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
15532 The access mode for the socket.
15533 Defaults to @samp{"0600"}.
15536 @deftypevr {@code{fifo-listener-configuration} parameter} string user
15537 The user to own the socket.
15538 Defaults to @samp{""}.
15541 @deftypevr {@code{fifo-listener-configuration} parameter} string group
15542 The group to own the socket.
15543 Defaults to @samp{""}.
15547 Available @code{inet-listener-configuration} fields are:
15549 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
15550 The protocol to listen for.
15553 @deftypevr {@code{inet-listener-configuration} parameter} string address
15554 The address on which to listen, or empty for all addresses.
15555 Defaults to @samp{""}.
15558 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
15559 The port on which to listen.
15562 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
15563 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
15565 Defaults to @samp{#t}.
15570 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
15571 Maximum number of simultaneous client connections per process. Once
15572 this number of connections is received, the next incoming connection
15573 will prompt Dovecot to spawn another process. If set to 0,
15574 @code{default-client-limit} is used instead.
15576 Defaults to @samp{0}.
15580 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
15581 Number of connections to handle before starting a new process.
15582 Typically the only useful values are 0 (unlimited) or 1. 1 is more
15583 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
15584 Defaults to @samp{1}.
15588 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
15589 Maximum number of processes that can exist for this service. If set to
15590 0, @code{default-process-limit} is used instead.
15592 Defaults to @samp{0}.
15596 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
15597 Number of processes to always keep waiting for more connections.
15598 Defaults to @samp{0}.
15601 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
15602 If you set @samp{service-count 0}, you probably need to grow
15604 Defaults to @samp{256000000}.
15609 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
15610 Dict configuration, as created by the @code{dict-configuration}
15613 Available @code{dict-configuration} fields are:
15615 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
15616 A list of key-value pairs that this dict should hold.
15617 Defaults to @samp{()}.
15622 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
15623 A list of passdb configurations, each one created by the
15624 @code{passdb-configuration} constructor.
15626 Available @code{passdb-configuration} fields are:
15628 @deftypevr {@code{passdb-configuration} parameter} string driver
15629 The driver that the passdb should use. Valid values include
15630 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
15632 Defaults to @samp{"pam"}.
15635 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
15636 Space separated list of arguments to the passdb driver.
15637 Defaults to @samp{""}.
15642 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
15643 List of userdb configurations, each one created by the
15644 @code{userdb-configuration} constructor.
15646 Available @code{userdb-configuration} fields are:
15648 @deftypevr {@code{userdb-configuration} parameter} string driver
15649 The driver that the userdb should use. Valid values include
15650 @samp{passwd} and @samp{static}.
15651 Defaults to @samp{"passwd"}.
15654 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
15655 Space separated list of arguments to the userdb driver.
15656 Defaults to @samp{""}.
15659 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
15660 Override fields from passwd.
15661 Defaults to @samp{()}.
15666 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
15667 Plug-in configuration, created by the @code{plugin-configuration}
15671 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
15672 List of namespaces. Each item in the list is created by the
15673 @code{namespace-configuration} constructor.
15675 Available @code{namespace-configuration} fields are:
15677 @deftypevr {@code{namespace-configuration} parameter} string name
15678 Name for this namespace.
15681 @deftypevr {@code{namespace-configuration} parameter} string type
15682 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
15683 Defaults to @samp{"private"}.
15686 @deftypevr {@code{namespace-configuration} parameter} string separator
15687 Hierarchy separator to use. You should use the same separator for
15688 all namespaces or some clients get confused. @samp{/} is usually a good
15689 one. The default however depends on the underlying mail storage
15691 Defaults to @samp{""}.
15694 @deftypevr {@code{namespace-configuration} parameter} string prefix
15695 Prefix required to access this namespace. This needs to be
15696 different for all namespaces. For example @samp{Public/}.
15697 Defaults to @samp{""}.
15700 @deftypevr {@code{namespace-configuration} parameter} string location
15701 Physical location of the mailbox. This is in the same format as
15702 mail_location, which is also the default for it.
15703 Defaults to @samp{""}.
15706 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
15707 There can be only one INBOX, and this setting defines which
15709 Defaults to @samp{#f}.
15712 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
15713 If namespace is hidden, it's not advertised to clients via NAMESPACE
15714 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
15715 useful when converting from another server with different namespaces
15716 which you want to deprecate but still keep working. For example you can
15717 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
15719 Defaults to @samp{#f}.
15722 @deftypevr {@code{namespace-configuration} parameter} boolean list?
15723 Show the mailboxes under this namespace with the LIST command. This
15724 makes the namespace visible for clients that do not support the NAMESPACE
15725 extension. The special @code{children} value lists child mailboxes, but
15726 hides the namespace prefix.
15727 Defaults to @samp{#t}.
15730 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
15731 Namespace handles its own subscriptions. If set to @code{#f}, the
15732 parent namespace handles them. The empty prefix should always have this
15734 Defaults to @samp{#t}.
15737 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
15738 List of predefined mailboxes in this namespace.
15739 Defaults to @samp{()}.
15741 Available @code{mailbox-configuration} fields are:
15743 @deftypevr {@code{mailbox-configuration} parameter} string name
15744 Name for this mailbox.
15747 @deftypevr {@code{mailbox-configuration} parameter} string auto
15748 @samp{create} will automatically create this mailbox.
15749 @samp{subscribe} will both create and subscribe to the mailbox.
15750 Defaults to @samp{"no"}.
15753 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
15754 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
15755 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
15756 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
15757 Defaults to @samp{()}.
15764 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
15765 Base directory where to store runtime data.
15766 Defaults to @samp{"/var/run/dovecot/"}.
15769 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
15770 Greeting message for clients.
15771 Defaults to @samp{"Dovecot ready."}.
15774 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
15775 List of trusted network ranges. Connections from these IPs are
15776 allowed to override their IP addresses and ports (for logging and for
15777 authentication checks). @samp{disable-plaintext-auth} is also ignored
15778 for these networks. Typically you would specify your IMAP proxy servers
15780 Defaults to @samp{()}.
15783 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
15784 List of login access check sockets (e.g.@: tcpwrap).
15785 Defaults to @samp{()}.
15788 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
15789 Show more verbose process titles (in ps). Currently shows user name
15790 and IP address. Useful for seeing who is actually using the IMAP
15791 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
15793 Defaults to @samp{#f}.
15796 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
15797 Should all processes be killed when Dovecot master process shuts down.
15798 Setting this to @code{#f} means that Dovecot can be upgraded without
15799 forcing existing client connections to close (although that could also
15800 be a problem if the upgrade is e.g.@: due to a security fix).
15801 Defaults to @samp{#t}.
15804 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
15805 If non-zero, run mail commands via this many connections to doveadm
15806 server, instead of running them directly in the same process.
15807 Defaults to @samp{0}.
15810 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
15811 UNIX socket or host:port used for connecting to doveadm server.
15812 Defaults to @samp{"doveadm-server"}.
15815 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
15816 List of environment variables that are preserved on Dovecot startup
15817 and passed down to all of its child processes. You can also give
15818 key=value pairs to always set specific settings.
15821 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
15822 Disable LOGIN command and all other plaintext authentications unless
15823 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
15824 matches the local IP (i.e.@: you're connecting from the same computer),
15825 the connection is considered secure and plaintext authentication is
15826 allowed. See also ssl=required setting.
15827 Defaults to @samp{#t}.
15830 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
15831 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
15832 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
15833 for caching to be used.
15834 Defaults to @samp{0}.
15837 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
15838 Time to live for cached data. After TTL expires the cached record
15839 is no longer used, *except* if the main database lookup returns internal
15840 failure. We also try to handle password changes automatically: If
15841 user's previous authentication was successful, but this one wasn't, the
15842 cache isn't used. For now this works only with plaintext
15844 Defaults to @samp{"1 hour"}.
15847 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
15848 TTL for negative hits (user not found, password mismatch).
15849 0 disables caching them completely.
15850 Defaults to @samp{"1 hour"}.
15853 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
15854 List of realms for SASL authentication mechanisms that need them.
15855 You can leave it empty if you don't want to support multiple realms.
15856 Many clients simply use the first one listed here, so keep the default
15858 Defaults to @samp{()}.
15861 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
15862 Default realm/domain to use if none was specified. This is used for
15863 both SASL realms and appending @@domain to username in plaintext
15865 Defaults to @samp{""}.
15868 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
15869 List of allowed characters in username. If the user-given username
15870 contains a character not listed in here, the login automatically fails.
15871 This is just an extra check to make sure user can't exploit any
15872 potential quote escaping vulnerabilities with SQL/LDAP databases. If
15873 you want to allow all characters, set this value to empty.
15874 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
15877 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
15878 Username character translations before it's looked up from
15879 databases. The value contains series of from -> to characters. For
15880 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
15881 translated to @samp{@@}.
15882 Defaults to @samp{""}.
15885 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
15886 Username formatting before it's looked up from databases. You can
15887 use the standard variables here, e.g.@: %Lu would lowercase the username,
15888 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
15889 change the @samp{@@} into @samp{-AT-}. This translation is done after
15890 @samp{auth-username-translation} changes.
15891 Defaults to @samp{"%Lu"}.
15894 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
15895 If you want to allow master users to log in by specifying the master
15896 username within the normal username string (i.e.@: not using SASL
15897 mechanism's support for it), you can specify the separator character
15898 here. The format is then <username><separator><master username>.
15899 UW-IMAP uses @samp{*} as the separator, so that could be a good
15901 Defaults to @samp{""}.
15904 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
15905 Username to use for users logging in with ANONYMOUS SASL
15907 Defaults to @samp{"anonymous"}.
15910 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
15911 Maximum number of dovecot-auth worker processes. They're used to
15912 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
15913 They're automatically created and destroyed as needed.
15914 Defaults to @samp{30}.
15917 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
15918 Host name to use in GSSAPI principal names. The default is to use
15919 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
15920 allow all keytab entries.
15921 Defaults to @samp{""}.
15924 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
15925 Kerberos keytab to use for the GSSAPI mechanism. Will use the
15926 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
15927 need to change the auth service to run as root to be able to read this
15929 Defaults to @samp{""}.
15932 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
15933 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
15934 and @samp{ntlm-auth} helper.
15935 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
15936 Defaults to @samp{#f}.
15939 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
15940 Path for Samba's @samp{ntlm-auth} helper binary.
15941 Defaults to @samp{"/usr/bin/ntlm_auth"}.
15944 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
15945 Time to delay before replying to failed authentications.
15946 Defaults to @samp{"2 secs"}.
15949 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
15950 Require a valid SSL client certificate or the authentication
15952 Defaults to @samp{#f}.
15955 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
15956 Take the username from client's SSL certificate, using
15957 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
15959 Defaults to @samp{#f}.
15962 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
15963 List of wanted authentication mechanisms. Supported mechanisms are:
15964 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
15965 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
15966 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
15967 @samp{disable-plaintext-auth} setting.
15970 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
15971 List of IPs or hostnames to all director servers, including ourself.
15972 Ports can be specified as ip:port. The default port is the same as what
15973 director service's @samp{inet-listener} is using.
15974 Defaults to @samp{()}.
15977 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
15978 List of IPs or hostnames to all backend mail servers. Ranges are
15979 allowed too, like 10.0.0.10-10.0.0.30.
15980 Defaults to @samp{()}.
15983 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
15984 How long to redirect users to a specific server after it no longer
15985 has any connections.
15986 Defaults to @samp{"15 min"}.
15989 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
15990 How the username is translated before being hashed. Useful values
15991 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
15992 are shared within domain.
15993 Defaults to @samp{"%Lu"}.
15996 @deftypevr {@code{dovecot-configuration} parameter} string log-path
15997 Log file to use for error messages. @samp{syslog} logs to syslog,
15998 @samp{/dev/stderr} logs to stderr.
15999 Defaults to @samp{"syslog"}.
16002 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
16003 Log file to use for informational messages. Defaults to
16005 Defaults to @samp{""}.
16008 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
16009 Log file to use for debug messages. Defaults to
16010 @samp{info-log-path}.
16011 Defaults to @samp{""}.
16014 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
16015 Syslog facility to use if you're logging to syslog. Usually if you
16016 don't want to use @samp{mail}, you'll use local0..local7. Also other
16017 standard facilities are supported.
16018 Defaults to @samp{"mail"}.
16021 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
16022 Log unsuccessful authentication attempts and the reasons why they
16024 Defaults to @samp{#f}.
16027 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
16028 In case of password mismatches, log the attempted password. Valid
16029 values are no, plain and sha1. sha1 can be useful for detecting brute
16030 force password attempts vs. user simply trying the same password over
16031 and over again. You can also truncate the value to n chars by appending
16032 ":n" (e.g.@: sha1:6).
16033 Defaults to @samp{"no"}.
16036 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
16037 Even more verbose logging for debugging purposes. Shows for example
16039 Defaults to @samp{#f}.
16042 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
16043 In case of password mismatches, log the passwords and used scheme so
16044 the problem can be debugged. Enabling this also enables
16046 Defaults to @samp{#f}.
16049 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
16050 Enable mail process debugging. This can help you figure out why
16051 Dovecot isn't finding your mails.
16052 Defaults to @samp{#f}.
16055 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
16056 Show protocol level SSL errors.
16057 Defaults to @samp{#f}.
16060 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
16061 Prefix for each line written to log file. % codes are in
16062 strftime(3) format.
16063 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
16066 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
16067 List of elements we want to log. The elements which have a
16068 non-empty variable value are joined together to form a comma-separated
16072 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
16073 Login log format. %s contains @samp{login-log-format-elements}
16074 string, %$ contains the data we want to log.
16075 Defaults to @samp{"%$: %s"}.
16078 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
16079 Log prefix for mail processes. See doc/wiki/Variables.txt for list
16080 of possible variables you can use.
16081 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
16084 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
16085 Format to use for logging mail deliveries. You can use variables:
16088 Delivery status message (e.g.@: @samp{saved to INBOX})
16100 Defaults to @samp{"msgid=%m: %$"}.
16103 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
16104 Location for users' mailboxes. The default is empty, which means
16105 that Dovecot tries to find the mailboxes automatically. This won't work
16106 if the user doesn't yet have any mail, so you should explicitly tell
16107 Dovecot the full location.
16109 If you're using mbox, giving a path to the INBOX
16110 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
16111 where the other mailboxes are kept. This is called the "root mail
16112 directory", and it must be the first path given in the
16113 @samp{mail-location} setting.
16115 There are a few special variables you can use, eg.:
16121 user part in user@@domain, same as %u if there's no domain
16123 domain part in user@@domain, empty if there's no domain
16128 See doc/wiki/Variables.txt for full list. Some examples:
16130 @item maildir:~/Maildir
16131 @item mbox:~/mail:INBOX=/var/mail/%u
16132 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
16134 Defaults to @samp{""}.
16137 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
16138 System user and group used to access mails. If you use multiple,
16139 userdb can override these by returning uid or gid fields. You can use
16140 either numbers or names. <doc/wiki/UserIds.txt>.
16141 Defaults to @samp{""}.
16144 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
16146 Defaults to @samp{""}.
16149 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
16150 Group to enable temporarily for privileged operations. Currently
16151 this is used only with INBOX when either its initial creation or
16152 dotlocking fails. Typically this is set to "mail" to give access to
16154 Defaults to @samp{""}.
16157 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
16158 Grant access to these supplementary groups for mail processes.
16159 Typically these are used to set up access to shared mailboxes. Note
16160 that it may be dangerous to set these if users can create
16161 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
16162 could allow a user to delete others' mailboxes, or ln -s
16163 /secret/shared/box ~/mail/mybox would allow reading it).
16164 Defaults to @samp{""}.
16167 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
16168 Allow full file system access to clients. There's no access checks
16169 other than what the operating system does for the active UID/GID. It
16170 works with both maildir and mboxes, allowing you to prefix mailboxes
16171 names with e.g.@: /path/ or ~user/.
16172 Defaults to @samp{#f}.
16175 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
16176 Don't use mmap() at all. This is required if you store indexes to
16177 shared file systems (NFS or clustered file system).
16178 Defaults to @samp{#f}.
16181 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
16182 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
16183 supports @samp{O_EXCL} since version 3, so this should be safe to use
16184 nowadays by default.
16185 Defaults to @samp{#t}.
16188 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
16189 When to use fsync() or fdatasync() calls:
16192 Whenever necessary to avoid losing important data
16194 Useful with e.g.@: NFS when write()s are delayed
16196 Never use it (best performance, but crashes can lose data).
16198 Defaults to @samp{"optimized"}.
16201 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
16202 Mail storage exists in NFS. Set this to yes to make Dovecot flush
16203 NFS caches whenever needed. If you're using only a single mail server
16205 Defaults to @samp{#f}.
16208 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
16209 Mail index files also exist in NFS. Setting this to yes requires
16210 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
16211 Defaults to @samp{#f}.
16214 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
16215 Locking method for index files. Alternatives are fcntl, flock and
16216 dotlock. Dotlocking uses some tricks which may create more disk I/O
16217 than other locking methods. NFS users: flock doesn't work, remember to
16218 change @samp{mmap-disable}.
16219 Defaults to @samp{"fcntl"}.
16222 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
16223 Directory in which LDA/LMTP temporarily stores incoming mails >128
16225 Defaults to @samp{"/tmp"}.
16228 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
16229 Valid UID range for users. This is mostly to make sure that users can't
16230 log in as daemons or other system users. Note that denying root logins is
16231 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
16233 Defaults to @samp{500}.
16236 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
16238 Defaults to @samp{0}.
16241 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
16242 Valid GID range for users. Users having non-valid GID as primary group ID
16243 aren't allowed to log in. If user belongs to supplementary groups with
16244 non-valid GIDs, those groups are not set.
16245 Defaults to @samp{1}.
16248 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
16250 Defaults to @samp{0}.
16253 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
16254 Maximum allowed length for mail keyword name. It's only forced when
16255 trying to create new keywords.
16256 Defaults to @samp{50}.
16259 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
16260 List of directories under which chrooting is allowed for mail
16261 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
16262 too). This setting doesn't affect @samp{login-chroot}
16263 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
16264 "/./" in home dirs are ignored. WARNING: Never add directories here
16265 which local users can modify, that may lead to root exploit. Usually
16266 this should be done only if you don't allow shell access for users.
16267 <doc/wiki/Chrooting.txt>.
16268 Defaults to @samp{()}.
16271 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
16272 Default chroot directory for mail processes. This can be overridden
16273 for specific users in user database by giving /./ in user's home
16274 directory (e.g.@: /home/./user chroots into /home). Note that usually
16275 there is no real need to do chrooting, Dovecot doesn't allow users to
16276 access files outside their mail directory anyway. If your home
16277 directories are prefixed with the chroot directory, append "/."@: to
16278 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
16279 Defaults to @samp{""}.
16282 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
16283 UNIX socket path to master authentication server to find users.
16284 This is used by imap (for shared users) and lda.
16285 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16288 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
16289 Directory where to look up mail plugins.
16290 Defaults to @samp{"/usr/lib/dovecot"}.
16293 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
16294 List of plugins to load for all services. Plugins specific to IMAP,
16295 LDA, etc.@: are added to this list in their own .conf files.
16296 Defaults to @samp{()}.
16299 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
16300 The minimum number of mails in a mailbox before updates are done to
16301 cache file. This allows optimizing Dovecot's behavior to do less disk
16302 writes at the cost of more disk reads.
16303 Defaults to @samp{0}.
16306 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
16307 When IDLE command is running, mailbox is checked once in a while to
16308 see if there are any new mails or other changes. This setting defines
16309 the minimum time to wait between those checks. Dovecot can also use
16310 dnotify, inotify and kqueue to find out immediately when changes
16312 Defaults to @samp{"30 secs"}.
16315 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
16316 Save mails with CR+LF instead of plain LF. This makes sending those
16317 mails take less CPU, especially with sendfile() syscall with Linux and
16318 FreeBSD. But it also creates a bit more disk I/O which may just make it
16319 slower. Also note that if other software reads the mboxes/maildirs,
16320 they may handle the extra CRs wrong and cause problems.
16321 Defaults to @samp{#f}.
16324 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
16325 By default LIST command returns all entries in maildir beginning
16326 with a dot. Enabling this option makes Dovecot return only entries
16327 which are directories. This is done by stat()ing each entry, so it
16328 causes more disk I/O.
16329 (For systems setting struct @samp{dirent->d_type} this check is free
16330 and it's done always regardless of this setting).
16331 Defaults to @samp{#f}.
16334 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
16335 When copying a message, do it with hard links whenever possible.
16336 This makes the performance much better, and it's unlikely to have any
16338 Defaults to @samp{#t}.
16341 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
16342 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
16343 directory only when its mtime changes unexpectedly or when we can't find
16344 the mail otherwise.
16345 Defaults to @samp{#f}.
16348 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
16349 Which locking methods to use for locking mbox. There are four
16354 Create <mailbox>.lock file. This is the oldest and most NFS-safe
16355 solution. If you want to use /var/mail/ like directory, the users will
16356 need write access to that directory.
16358 Same as dotlock, but if it fails because of permissions or because there
16359 isn't enough disk space, just skip it.
16361 Use this if possible. Works with NFS too if lockd is used.
16363 May not exist in all systems. Doesn't work with NFS.
16365 May not exist in all systems. Doesn't work with NFS.
16368 You can use multiple locking methods; if you do the order they're declared
16369 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
16370 locking methods as well. Some operating systems don't allow using some of
16371 them simultaneously.
16374 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
16378 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
16379 Maximum time to wait for lock (all of them) before aborting.
16380 Defaults to @samp{"5 mins"}.
16383 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
16384 If dotlock exists but the mailbox isn't modified in any way,
16385 override the lock file after this much time.
16386 Defaults to @samp{"2 mins"}.
16389 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
16390 When mbox changes unexpectedly we have to fully read it to find out
16391 what changed. If the mbox is large this can take a long time. Since
16392 the change is usually just a newly appended mail, it'd be faster to
16393 simply read the new mails. If this setting is enabled, Dovecot does
16394 this but still safely fallbacks to re-reading the whole mbox file
16395 whenever something in mbox isn't how it's expected to be. The only real
16396 downside to this setting is that if some other MUA changes message
16397 flags, Dovecot doesn't notice it immediately. Note that a full sync is
16398 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
16399 Defaults to @samp{#t}.
16402 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
16403 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
16404 EXAMINE, EXPUNGE or CHECK commands. If this is set,
16405 @samp{mbox-dirty-syncs} is ignored.
16406 Defaults to @samp{#f}.
16409 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
16410 Delay writing mbox headers until doing a full write sync (EXPUNGE
16411 and CHECK commands and when closing the mailbox). This is especially
16412 useful for POP3 where clients often delete all mails. The downside is
16413 that our changes aren't immediately visible to other MUAs.
16414 Defaults to @samp{#t}.
16417 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
16418 If mbox size is smaller than this (e.g.@: 100k), don't write index
16419 files. If an index file already exists it's still read, just not
16421 Defaults to @samp{0}.
16424 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
16425 Maximum dbox file size until it's rotated.
16426 Defaults to @samp{10000000}.
16429 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
16430 Maximum dbox file age until it's rotated. Typically in days. Day
16431 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
16433 Defaults to @samp{"1d"}.
16436 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
16437 When creating new mdbox files, immediately preallocate their size to
16438 @samp{mdbox-rotate-size}. This setting currently works only in Linux
16439 with some file systems (ext4, xfs).
16440 Defaults to @samp{#f}.
16443 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
16444 sdbox and mdbox support saving mail attachments to external files,
16445 which also allows single instance storage for them. Other backends
16446 don't support this for now.
16448 WARNING: This feature hasn't been tested much yet. Use at your own risk.
16450 Directory root where to store mail attachments. Disabled, if empty.
16451 Defaults to @samp{""}.
16454 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
16455 Attachments smaller than this aren't saved externally. It's also
16456 possible to write a plugin to disable saving specific attachments
16458 Defaults to @samp{128000}.
16461 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
16462 File system backend to use for saving attachments:
16465 No SiS done by Dovecot (but this might help FS's own deduplication)
16467 SiS with immediate byte-by-byte comparison during saving
16468 @item sis-queue posix
16469 SiS with delayed comparison and deduplication.
16471 Defaults to @samp{"sis posix"}.
16474 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
16475 Hash format to use in attachment filenames. You can add any text and
16476 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
16477 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
16478 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
16479 Defaults to @samp{"%@{sha1@}"}.
16482 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
16484 Defaults to @samp{100}.
16487 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
16489 Defaults to @samp{1000}.
16492 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
16493 Default VSZ (virtual memory size) limit for service processes.
16494 This is mainly intended to catch and kill processes that leak memory
16495 before they eat up everything.
16496 Defaults to @samp{256000000}.
16499 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
16500 Login user is internally used by login processes. This is the most
16501 untrusted user in Dovecot system. It shouldn't have access to anything
16503 Defaults to @samp{"dovenull"}.
16506 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
16507 Internal user is used by unprivileged processes. It should be
16508 separate from login user, so that login processes can't disturb other
16510 Defaults to @samp{"dovecot"}.
16513 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
16514 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
16515 Defaults to @samp{"required"}.
16518 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
16519 PEM encoded X.509 SSL/TLS certificate (public key).
16520 Defaults to @samp{"</etc/dovecot/default.pem"}.
16523 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
16524 PEM encoded SSL/TLS private key. The key is opened before
16525 dropping root privileges, so keep the key file unreadable by anyone but
16527 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
16530 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
16531 If key file is password protected, give the password here.
16532 Alternatively give it when starting dovecot with -p parameter. Since
16533 this file is often world-readable, you may want to place this setting
16534 instead to a different.
16535 Defaults to @samp{""}.
16538 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
16539 PEM encoded trusted certificate authority. Set this only if you
16540 intend to use @samp{ssl-verify-client-cert? #t}. The file should
16541 contain the CA certificate(s) followed by the matching
16542 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
16543 Defaults to @samp{""}.
16546 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
16547 Require that CRL check succeeds for client certificates.
16548 Defaults to @samp{#t}.
16551 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
16552 Request client to send a certificate. If you also want to require
16553 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
16554 Defaults to @samp{#f}.
16557 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
16558 Which field from certificate to use for username. commonName and
16559 x500UniqueIdentifier are the usual choices. You'll also need to set
16560 @samp{auth-ssl-username-from-cert? #t}.
16561 Defaults to @samp{"commonName"}.
16564 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
16565 Minimum SSL protocol version to accept.
16566 Defaults to @samp{"TLSv1"}.
16569 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
16570 SSL ciphers to use.
16571 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
16574 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
16575 SSL crypto device to use, for valid values run "openssl engine".
16576 Defaults to @samp{""}.
16579 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
16580 Address to use when sending rejection mails.
16581 %d expands to recipient domain.
16582 Defaults to @samp{"postmaster@@%d"}.
16585 @deftypevr {@code{dovecot-configuration} parameter} string hostname
16586 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
16587 and in LMTP replies. Default is the system's real hostname@@domain.
16588 Defaults to @samp{""}.
16591 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
16592 If user is over quota, return with temporary failure instead of
16594 Defaults to @samp{#f}.
16597 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
16598 Binary to use for sending mails.
16599 Defaults to @samp{"/usr/sbin/sendmail"}.
16602 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
16603 If non-empty, send mails via this SMTP host[:port] instead of
16605 Defaults to @samp{""}.
16608 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
16609 Subject: header to use for rejection mails. You can use the same
16610 variables as for @samp{rejection-reason} below.
16611 Defaults to @samp{"Rejected: %s"}.
16614 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
16615 Human readable error message for rejection mails. You can use
16628 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
16631 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
16632 Delimiter character between local-part and detail in email
16634 Defaults to @samp{"+"}.
16637 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
16638 Header where the original recipient address (SMTP's RCPT TO:
16639 address) is taken from if not available elsewhere. With dovecot-lda -a
16640 parameter overrides this. A commonly used header for this is
16642 Defaults to @samp{""}.
16645 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
16646 Should saving a mail to a nonexistent mailbox automatically create
16648 Defaults to @samp{#f}.
16651 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
16652 Should automatically created mailboxes be also automatically
16654 Defaults to @samp{#f}.
16657 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
16658 Maximum IMAP command line length. Some clients generate very long
16659 command lines with huge mailboxes, so you may need to raise this if you
16660 get "Too long argument" or "IMAP command line too large" errors
16662 Defaults to @samp{64000}.
16665 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
16666 IMAP logout format string:
16669 total number of bytes read from client
16671 total number of bytes sent to client.
16673 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
16674 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@}"}.
16677 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
16678 Override the IMAP CAPABILITY response. If the value begins with '+',
16679 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
16680 Defaults to @samp{""}.
16683 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
16684 How long to wait between "OK Still here" notifications when client
16686 Defaults to @samp{"2 mins"}.
16689 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
16690 ID field names and values to send to clients. Using * as the value
16691 makes Dovecot use the default value. The following fields have default
16692 values currently: name, version, os, os-version, support-url,
16694 Defaults to @samp{""}.
16697 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
16698 ID fields sent by client to log. * means everything.
16699 Defaults to @samp{""}.
16702 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
16703 Workarounds for various client bugs:
16706 @item delay-newmail
16707 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
16708 CHECK commands. Some clients ignore them otherwise, for example OSX
16709 Mail (<v2.1). Outlook Express breaks more badly though, without this it
16710 may show user "Message no longer in server" errors. Note that OE6
16711 still breaks even with this workaround if synchronization is set to
16714 @item tb-extra-mailbox-sep
16715 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
16716 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
16717 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
16719 @item tb-lsub-flags
16720 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
16721 This makes Thunderbird realize they aren't selectable and show them
16722 greyed out, instead of only later giving "not selectable" popup error.
16724 Defaults to @samp{()}.
16727 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
16728 Host allowed in URLAUTH URLs sent by client. "*" allows all.
16729 Defaults to @samp{""}.
16733 Whew! Lots of configuration options. The nice thing about it though is
16734 that Guix has a complete interface to Dovecot's configuration
16735 language. This allows not only a nice way to declare configurations,
16736 but also offers reflective capabilities as well: users can write code to
16737 inspect and transform configurations from within Scheme.
16739 However, it could be that you just want to get a @code{dovecot.conf} up
16740 and running. In that case, you can pass an
16741 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
16742 @code{dovecot-service}. As its name indicates, an opaque configuration
16743 does not have easy reflective capabilities.
16745 Available @code{opaque-dovecot-configuration} fields are:
16747 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
16748 The dovecot package.
16751 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
16752 The contents of the @code{dovecot.conf}, as a string.
16755 For example, if your @code{dovecot.conf} is just the empty string, you
16756 could instantiate a dovecot service like this:
16759 (dovecot-service #:config
16760 (opaque-dovecot-configuration
16764 @subsubheading OpenSMTPD Service
16766 @deffn {Scheme Variable} opensmtpd-service-type
16767 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
16768 service, whose value should be an @code{opensmtpd-configuration} object
16769 as in this example:
16772 (service opensmtpd-service-type
16773 (opensmtpd-configuration
16774 (config-file (local-file "./my-smtpd.conf"))))
16778 @deftp {Data Type} opensmtpd-configuration
16779 Data type representing the configuration of opensmtpd.
16782 @item @code{package} (default: @var{opensmtpd})
16783 Package object of the OpenSMTPD SMTP server.
16785 @item @code{config-file} (default: @code{%default-opensmtpd-file})
16786 File-like object of the OpenSMTPD configuration file to use. By default
16787 it listens on the loopback network interface, and allows for mail from
16788 users and daemons on the local machine, as well as permitting email to
16789 remote servers. Run @command{man smtpd.conf} for more information.
16794 @subsubheading Exim Service
16796 @cindex mail transfer agent (MTA)
16797 @cindex MTA (mail transfer agent)
16800 @deffn {Scheme Variable} exim-service-type
16801 This is the type of the @uref{https://exim.org, Exim} mail transfer
16802 agent (MTA), whose value should be an @code{exim-configuration} object
16803 as in this example:
16806 (service exim-service-type
16807 (exim-configuration
16808 (config-file (local-file "./my-exim.conf"))))
16812 In order to use an @code{exim-service-type} service you must also have a
16813 @code{mail-aliases-service-type} service present in your
16814 @code{operating-system} (even if it has no aliases).
16816 @deftp {Data Type} exim-configuration
16817 Data type representing the configuration of exim.
16820 @item @code{package} (default: @var{exim})
16821 Package object of the Exim server.
16823 @item @code{config-file} (default: @code{#f})
16824 File-like object of the Exim configuration file to use. If its value is
16825 @code{#f} then use the default configuration file from the package
16826 provided in @code{package}. The resulting configuration file is loaded
16827 after setting the @code{exim_user} and @code{exim_group} configuration
16833 @subsubheading Getmail service
16838 @deffn {Scheme Variable} getmail-service-type
16839 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
16840 mail retriever, whose value should be an @code{getmail-configuration}.
16843 Available @code{getmail-configuration} fields are:
16845 @deftypevr {@code{getmail-configuration} parameter} symbol name
16846 A symbol to identify the getmail service.
16848 Defaults to @samp{"unset"}.
16852 @deftypevr {@code{getmail-configuration} parameter} package package
16853 The getmail package to use.
16857 @deftypevr {@code{getmail-configuration} parameter} string user
16858 The user to run getmail as.
16860 Defaults to @samp{"getmail"}.
16864 @deftypevr {@code{getmail-configuration} parameter} string group
16865 The group to run getmail as.
16867 Defaults to @samp{"getmail"}.
16871 @deftypevr {@code{getmail-configuration} parameter} string directory
16872 The getmail directory to use.
16874 Defaults to @samp{"/var/lib/getmail/default"}.
16878 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
16879 The getmail configuration file to use.
16881 Available @code{getmail-configuration-file} fields are:
16883 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
16884 What mail account to retrieve mail from, and how to access that account.
16886 Available @code{getmail-retriever-configuration} fields are:
16888 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
16889 The type of mail retriever to use. Valid values include @samp{passwd}
16892 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
16896 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
16897 Space separated list of arguments to the userdb driver.
16899 Defaults to @samp{unset}.
16903 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
16904 Space separated list of arguments to the userdb driver.
16906 Defaults to @samp{unset}.
16910 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
16911 Space separated list of arguments to the userdb driver.
16913 Defaults to @samp{#f}.
16917 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
16918 Override fields from passwd.
16920 Defaults to @samp{""}.
16924 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
16925 Override fields from passwd.
16927 Defaults to @samp{()}.
16931 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
16932 PEM-formatted key file to use for the TLS negotiation
16934 Defaults to @samp{""}.
16938 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
16939 PEM-formatted certificate file to use for the TLS negotiation
16941 Defaults to @samp{""}.
16945 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
16946 CA certificates to use
16948 Defaults to @samp{""}.
16952 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
16953 Extra retriever parameters
16955 Defaults to @samp{()}.
16961 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
16962 What to do with retrieved messages.
16964 Available @code{getmail-destination-configuration} fields are:
16966 @deftypevr {@code{getmail-destination-configuration} parameter} string type
16967 The type of mail destination. Valid values include @samp{Maildir},
16968 @samp{Mboxrd} and @samp{MDA_external}.
16970 Defaults to @samp{unset}.
16974 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
16975 The path option for the mail destination. The behaviour depends on the
16978 Defaults to @samp{""}.
16982 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
16983 Extra destination parameters
16985 Defaults to @samp{()}.
16991 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
16994 Available @code{getmail-options-configuration} fields are:
16996 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
16997 If set to @samp{0}, getmail will only print warnings and errors. A
16998 value of @samp{1} means that messages will be printed about retrieving
16999 and deleting messages. If set to @samp{2}, getmail will print messages
17000 about each of it's actions.
17002 Defaults to @samp{1}.
17006 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
17007 If true, getmail will retrieve all available messages. Otherwise it
17008 will only retrieve messages it hasn't seen previously.
17010 Defaults to @samp{#t}.
17014 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
17015 If set to true, messages will be deleted from the server after
17016 retrieving and successfully delivering them. Otherwise, messages will
17017 be left on the server.
17019 Defaults to @samp{#f}.
17023 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
17024 Getmail will delete messages this number of days after seeing them, if
17025 they have not been delivered. This means messages will be left on the
17026 server this number of days after delivering them. A value of @samp{0}
17027 disabled this feature.
17029 Defaults to @samp{0}.
17033 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
17034 Delete messages larger than this of bytes after retrieving them, even if
17035 the delete and delete-after options are disabled. A value of @samp{0}
17036 disables this feature.
17038 Defaults to @samp{0}.
17042 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
17043 Retrieve messages totalling up to this number of bytes before closing
17044 the session with the server. A value of @samp{0} disables this feature.
17046 Defaults to @samp{0}.
17050 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
17051 Don't retrieve messages larger than this number of bytes. A value of
17052 @samp{0} disables this feature.
17054 Defaults to @samp{0}.
17058 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
17059 If true, getmail will add a Delivered-To header to messages.
17061 Defaults to @samp{#t}.
17065 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
17066 If set, getmail adds a Received header to the messages.
17068 Defaults to @samp{#t}.
17072 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
17073 Getmail will record a log of its actions to the named file. A value of
17074 @samp{""} disables this feature.
17076 Defaults to @samp{""}.
17080 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
17081 If true, getmail will record a log of its actions using the system
17084 Defaults to @samp{#t}.
17088 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
17089 If true, getmail will log information about messages not retrieved and
17090 the reason for not retrieving them, as well as starting and ending
17093 Defaults to @samp{#t}.
17097 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
17098 Extra options to include.
17100 Defaults to @samp{()}.
17108 @deftypevr {@code{getmail-configuration} parameter} list idle
17109 A list of mailboxes that getmail should wait on the server for new mail
17110 notifications. This depends on the server supporting the IDLE
17113 Defaults to @samp{()}.
17117 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
17118 Environment variables to set for getmail.
17120 Defaults to @samp{()}.
17124 @subsubheading Mail Aliases Service
17126 @cindex email aliases
17127 @cindex aliases, for email addresses
17129 @deffn {Scheme Variable} mail-aliases-service-type
17130 This is the type of the service which provides @code{/etc/aliases},
17131 specifying how to deliver mail to users on this system.
17134 (service mail-aliases-service-type
17135 '(("postmaster" "bob")
17136 ("bob" "bob@@example.com" "bob@@example2.com")))
17140 The configuration for a @code{mail-aliases-service-type} service is an
17141 association list denoting how to deliver mail that comes to this
17142 system. Each entry is of the form @code{(alias addresses ...)}, with
17143 @code{alias} specifying the local alias and @code{addresses} specifying
17144 where to deliver this user's mail.
17146 The aliases aren't required to exist as users on the local system. In
17147 the above example, there doesn't need to be a @code{postmaster} entry in
17148 the @code{operating-system}'s @code{user-accounts} in order to deliver
17149 the @code{postmaster} mail to @code{bob} (which subsequently would
17150 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
17152 @subsubheading GNU Mailutils IMAP4 Daemon
17153 @cindex GNU Mailutils IMAP4 Daemon
17155 @deffn {Scheme Variable} imap4d-service-type
17156 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
17157 mailutils, GNU Mailutils Manual}), whose value should be an
17158 @code{imap4d-configuration} object as in this example:
17161 (service imap4d-service-type
17162 (imap4d-configuration
17163 (config-file (local-file "imap4d.conf"))))
17167 @deftp {Data Type} imap4d-configuration
17168 Data type representing the configuration of @command{imap4d}.
17171 @item @code{package} (default: @code{mailutils})
17172 The package that provides @command{imap4d}.
17174 @item @code{config-file} (default: @code{%default-imap4d-config-file})
17175 File-like object of the configuration file to use, by default it will listen
17176 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
17177 Mailutils Manual}, for details.
17182 @node Messaging Services
17183 @subsection Messaging Services
17188 The @code{(gnu services messaging)} module provides Guix service
17189 definitions for messaging services: currently only Prosody is supported.
17191 @subsubheading Prosody Service
17193 @deffn {Scheme Variable} prosody-service-type
17194 This is the type for the @uref{https://prosody.im, Prosody XMPP
17195 communication server}. Its value must be a @code{prosody-configuration}
17196 record as in this example:
17199 (service prosody-service-type
17200 (prosody-configuration
17201 (modules-enabled (cons "groups" "mam" %default-modules-enabled))
17204 (int-component-configuration
17205 (hostname "conference.example.net")
17207 (mod-muc (mod-muc-configuration)))))
17210 (virtualhost-configuration
17211 (domain "example.net"))))))
17214 See below for details about @code{prosody-configuration}.
17218 By default, Prosody does not need much configuration. Only one
17219 @code{virtualhosts} field is needed: it specifies the domain you wish
17222 You can perform various sanity checks on the generated configuration
17223 with the @code{prosodyctl check} command.
17225 Prosodyctl will also help you to import certificates from the
17226 @code{letsencrypt} directory so that the @code{prosody} user can access
17227 them. See @url{https://prosody.im/doc/letsencrypt}.
17230 prosodyctl --root cert import /etc/letsencrypt/live
17233 The available configuration parameters follow. Each parameter
17234 definition is preceded by its type; for example, @samp{string-list foo}
17235 indicates that the @code{foo} parameter should be specified as a list of
17236 strings. Types starting with @code{maybe-} denote parameters that won't
17237 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
17239 There is also a way to specify the configuration as a string, if you
17240 have an old @code{prosody.cfg.lua} file that you want to port over from
17241 some other system; see the end for more details.
17243 The @code{file-object} type designates either a file-like object
17244 (@pxref{G-Expressions, file-like objects}) or a file name.
17246 @c The following documentation was initially generated by
17247 @c (generate-documentation) in (gnu services messaging). Manually maintained
17248 @c documentation is better, so we shouldn't hesitate to edit below as
17249 @c needed. However if the change you want to make to this documentation
17250 @c can be done in an automated way, it's probably easier to change
17251 @c (generate-documentation) than to make it below and have to deal with
17252 @c the churn as Prosody updates.
17254 Available @code{prosody-configuration} fields are:
17256 @deftypevr {@code{prosody-configuration} parameter} package prosody
17257 The Prosody package.
17260 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
17261 Location of the Prosody data storage directory. See
17262 @url{https://prosody.im/doc/configure}.
17263 Defaults to @samp{"/var/lib/prosody"}.
17266 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
17267 Additional plugin directories. They are searched in all the specified
17268 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
17269 Defaults to @samp{()}.
17272 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
17273 Every virtual host and component needs a certificate so that clients and
17274 servers can securely verify its identity. Prosody will automatically load
17275 certificates/keys from the directory specified here.
17276 Defaults to @samp{"/etc/prosody/certs"}.
17279 @deftypevr {@code{prosody-configuration} parameter} string-list admins
17280 This is a list of accounts that are admins for the server. Note that you
17281 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
17282 @url{https://prosody.im/doc/creating_accounts}.
17283 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
17284 Defaults to @samp{()}.
17287 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
17288 Enable use of libevent for better performance under high load. See
17289 @url{https://prosody.im/doc/libevent}.
17290 Defaults to @samp{#f}.
17293 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
17294 This is the list of modules Prosody will load on startup. It looks for
17295 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
17296 Documentation on modules can be found at:
17297 @url{https://prosody.im/doc/modules}.
17298 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
17301 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
17302 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
17303 should you want to disable them then add them to this list.
17304 Defaults to @samp{()}.
17307 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
17308 Path to a text file where the shared groups are defined. If this path is
17309 empty then @samp{mod_groups} does nothing. See
17310 @url{https://prosody.im/doc/modules/mod_groups}.
17311 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
17314 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
17315 Disable account creation by default, for security. See
17316 @url{https://prosody.im/doc/creating_accounts}.
17317 Defaults to @samp{#f}.
17320 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
17321 These are the SSL/TLS-related settings. Most of them are disabled so to
17322 use Prosody's defaults. If you do not completely understand these options, do
17323 not add them to your config, it is easy to lower the security of your server
17324 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
17326 Available @code{ssl-configuration} fields are:
17328 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
17329 This determines what handshake to use.
17332 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
17333 Path to your private key file.
17336 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
17337 Path to your certificate file.
17340 @deftypevr {@code{ssl-configuration} parameter} file-object capath
17341 Path to directory containing root certificates that you wish Prosody to
17342 trust when verifying the certificates of remote servers.
17343 Defaults to @samp{"/etc/ssl/certs"}.
17346 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
17347 Path to a file containing root certificates that you wish Prosody to trust.
17348 Similar to @code{capath} but with all certificates concatenated together.
17351 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
17352 A list of verification options (these mostly map to OpenSSL's
17353 @code{set_verify()} flags).
17356 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
17357 A list of general options relating to SSL/TLS. These map to OpenSSL's
17358 @code{set_options()}. For a full list of options available in LuaSec, see the
17362 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
17363 How long a chain of certificate authorities to check when looking for a
17364 trusted root certificate.
17367 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
17368 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
17369 clients, and in what order.
17372 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
17373 A path to a file containing parameters for Diffie-Hellman key exchange. You
17374 can create such a file with:
17375 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
17378 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
17379 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
17380 @samp{"secp384r1"}.
17383 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
17384 A list of "extra" verification options.
17387 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
17388 Password for encrypted private keys.
17393 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
17394 Whether to force all client-to-server connections to be encrypted or not.
17395 See @url{https://prosody.im/doc/modules/mod_tls}.
17396 Defaults to @samp{#f}.
17399 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
17400 Set of mechanisms that will never be offered. See
17401 @url{https://prosody.im/doc/modules/mod_saslauth}.
17402 Defaults to @samp{("DIGEST-MD5")}.
17405 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
17406 Whether to force all server-to-server connections to be encrypted or not.
17407 See @url{https://prosody.im/doc/modules/mod_tls}.
17408 Defaults to @samp{#f}.
17411 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
17412 Whether to require encryption and certificate authentication. This
17413 provides ideal security, but requires servers you communicate with to support
17414 encryption AND present valid, trusted certificates. See
17415 @url{https://prosody.im/doc/s2s#security}.
17416 Defaults to @samp{#f}.
17419 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
17420 Many servers don't support encryption or have invalid or self-signed
17421 certificates. You can list domains here that will not be required to
17422 authenticate using certificates. They will be authenticated using DNS. See
17423 @url{https://prosody.im/doc/s2s#security}.
17424 Defaults to @samp{()}.
17427 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
17428 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
17429 valid certificates for some domains by specifying a list here. See
17430 @url{https://prosody.im/doc/s2s#security}.
17431 Defaults to @samp{()}.
17434 @deftypevr {@code{prosody-configuration} parameter} string authentication
17435 Select the authentication backend to use. The default provider stores
17436 passwords in plaintext and uses Prosody's configured data storage to store the
17437 authentication data. If you do not trust your server please see
17438 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
17439 about using the hashed backend. See also
17440 @url{https://prosody.im/doc/authentication}
17441 Defaults to @samp{"internal_plain"}.
17444 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
17445 Set logging options. Advanced logging configuration is not yet supported
17446 by the Prosody service. See @url{https://prosody.im/doc/logging}.
17447 Defaults to @samp{"*syslog"}.
17450 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
17451 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
17452 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
17455 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
17456 Maximum allowed size of the HTTP body (in bytes).
17459 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
17460 Some modules expose their own URL in various ways. This URL is built
17461 from the protocol, host and port used. If Prosody sits behind a proxy, the
17462 public URL will be @code{http-external-url} instead. See
17463 @url{https://prosody.im/doc/http#external_url}.
17466 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
17467 A host in Prosody is a domain on which user accounts can be created. For
17468 example if you want your users to have addresses like
17469 @samp{"john.smith@@example.com"} then you need to add a host
17470 @samp{"example.com"}. All options in this list will apply only to this host.
17472 Note: the name "virtual" host is used in configuration to avoid confusion with
17473 the actual physical host that Prosody is installed on. A single Prosody
17474 instance can serve many domains, each one defined as a VirtualHost entry in
17475 Prosody's configuration. Conversely a server that hosts a single domain would
17476 have just one VirtualHost entry.
17478 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
17480 Available @code{virtualhost-configuration} fields are:
17482 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:
17483 @deftypevr {@code{virtualhost-configuration} parameter} string domain
17484 Domain you wish Prosody to serve.
17489 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
17490 Components are extra services on a server which are available to clients,
17491 usually on a subdomain of the main server (such as
17492 @samp{"mycomponent.example.com"}). Example components might be chatroom
17493 servers, user directories, or gateways to other protocols.
17495 Internal components are implemented with Prosody-specific plugins. To add an
17496 internal component, you simply fill the hostname field, and the plugin you wish
17497 to use for the component.
17499 See @url{https://prosody.im/doc/components}.
17500 Defaults to @samp{()}.
17502 Available @code{int-component-configuration} fields are:
17504 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:
17505 @deftypevr {@code{int-component-configuration} parameter} string hostname
17506 Hostname of the component.
17509 @deftypevr {@code{int-component-configuration} parameter} string plugin
17510 Plugin you wish to use for the component.
17513 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
17514 Multi-user chat (MUC) is Prosody's module for allowing you to create
17515 hosted chatrooms/conferences for XMPP users.
17517 General information on setting up and using multi-user chatrooms can be found
17518 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
17519 which you should read if you are new to XMPP chatrooms.
17521 See also @url{https://prosody.im/doc/modules/mod_muc}.
17523 Available @code{mod-muc-configuration} fields are:
17525 @deftypevr {@code{mod-muc-configuration} parameter} string name
17526 The name to return in service discovery responses.
17527 Defaults to @samp{"Prosody Chatrooms"}.
17530 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
17531 If @samp{#t}, this will only allow admins to create new chatrooms.
17532 Otherwise anyone can create a room. The value @samp{"local"} restricts room
17533 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
17534 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
17535 restricts to service administrators only.
17536 Defaults to @samp{#f}.
17539 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
17540 Maximum number of history messages that will be sent to the member that has
17541 just joined the room.
17542 Defaults to @samp{20}.
17549 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
17550 External components use XEP-0114, which most standalone components
17551 support. To add an external component, you simply fill the hostname field. See
17552 @url{https://prosody.im/doc/components}.
17553 Defaults to @samp{()}.
17555 Available @code{ext-component-configuration} fields are:
17557 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:
17558 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
17559 Password which the component will use to log in.
17562 @deftypevr {@code{ext-component-configuration} parameter} string hostname
17563 Hostname of the component.
17568 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
17569 Port(s) Prosody listens on for component connections.
17570 Defaults to @samp{(5347)}.
17573 @deftypevr {@code{prosody-configuration} parameter} string component-interface
17574 Interface Prosody listens on for component connections.
17575 Defaults to @samp{"127.0.0.1"}.
17578 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
17579 Raw content that will be added to the configuration file.
17582 It could be that you just want to get a @code{prosody.cfg.lua}
17583 up and running. In that case, you can pass an
17584 @code{opaque-prosody-configuration} record as the value of
17585 @code{prosody-service-type}. As its name indicates, an opaque configuration
17586 does not have easy reflective capabilities.
17587 Available @code{opaque-prosody-configuration} fields are:
17589 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
17590 The prosody package.
17593 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
17594 The contents of the @code{prosody.cfg.lua} to use.
17597 For example, if your @code{prosody.cfg.lua} is just the empty
17598 string, you could instantiate a prosody service like this:
17601 (service prosody-service-type
17602 (opaque-prosody-configuration
17603 (prosody.cfg.lua "")))
17606 @c end of Prosody auto-generated documentation
17608 @subsubheading BitlBee Service
17610 @cindex IRC (Internet Relay Chat)
17611 @cindex IRC gateway
17612 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
17613 interface to a variety of messaging protocols such as XMPP.
17615 @defvr {Scheme Variable} bitlbee-service-type
17616 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
17617 gateway daemon. Its value is a @code{bitlbee-configuration} (see
17620 To have BitlBee listen on port 6667 on localhost, add this line to your
17624 (service bitlbee-service-type)
17628 @deftp {Data Type} bitlbee-configuration
17629 This is the configuration for BitlBee, with the following fields:
17632 @item @code{interface} (default: @code{"127.0.0.1"})
17633 @itemx @code{port} (default: @code{6667})
17634 Listen on the network interface corresponding to the IP address
17635 specified in @var{interface}, on @var{port}.
17637 When @var{interface} is @code{127.0.0.1}, only local clients can
17638 connect; when it is @code{0.0.0.0}, connections can come from any
17639 networking interface.
17641 @item @code{package} (default: @code{bitlbee})
17642 The BitlBee package to use.
17644 @item @code{plugins} (default: @code{'()})
17645 List of plugin packages to use---e.g., @code{bitlbee-discord}.
17647 @item @code{extra-settings} (default: @code{""})
17648 Configuration snippet added as-is to the BitlBee configuration file.
17652 @subsubheading Quassel Service
17654 @cindex IRC (Internet Relay Chat)
17655 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
17656 meaning that one or more clients can attach to and detach from the
17659 @defvr {Scheme Variable} quassel-service-type
17660 This is the service type for the @url{https://quassel-irc.org/,Quassel}
17661 IRC backend daemon. Its value is a @code{quassel-configuration}
17665 @deftp {Data Type} quassel-configuration
17666 This is the configuration for Quassel, with the following fields:
17669 @item @code{quassel} (default: @code{quassel})
17670 The Quassel package to use.
17672 @item @code{interface} (default: @code{"::,0.0.0.0"})
17673 @item @code{port} (default: @code{4242})
17674 Listen on the network interface(s) corresponding to the IPv4 or IPv6
17675 interfaces specified in the comma delimited @var{interface}, on
17678 @item @code{loglevel} (default: @code{"Info"})
17679 The level of logging desired. Accepted values are Debug, Info, Warning
17684 @node Telephony Services
17685 @subsection Telephony Services
17687 @cindex Murmur (VoIP server)
17688 @cindex VoIP server
17689 This section describes how to set up and run a Murmur server. Murmur is
17690 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
17693 @deftp {Data Type} murmur-configuration
17694 The service type for the Murmur server. An example configuration can
17698 (service murmur-service-type
17699 (murmur-configuration
17701 "Welcome to this Mumble server running on Guix!")
17702 (cert-required? #t) ;disallow text password logins
17703 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
17704 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
17707 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
17708 password with the command that is printed during the activation phase.
17710 It is recommended to register a normal Mumble user account
17711 and grant it admin or moderator rights.
17712 You can use the @code{mumble} client to
17713 login as new normal user, register yourself, and log out.
17714 For the next step login with the name @code{SuperUser} use
17715 the @code{SuperUser} password that you set previously,
17716 and grant your newly registered mumble user administrator or moderator
17717 rights and create some channels.
17719 Available @code{murmur-configuration} fields are:
17722 @item @code{package} (default: @code{mumble})
17723 Package that contains @code{bin/murmurd}.
17725 @item @code{user} (default: @code{"murmur"})
17726 User who will run the Murmur server.
17728 @item @code{group} (default: @code{"murmur"})
17729 Group of the user who will run the murmur server.
17731 @item @code{port} (default: @code{64738})
17732 Port on which the server will listen.
17734 @item @code{welcome-text} (default: @code{""})
17735 Welcome text sent to clients when they connect.
17737 @item @code{server-password} (default: @code{""})
17738 Password the clients have to enter in order to connect.
17740 @item @code{max-users} (default: @code{100})
17741 Maximum of users that can be connected to the server at once.
17743 @item @code{max-user-bandwidth} (default: @code{#f})
17744 Maximum voice traffic a user can send per second.
17746 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
17747 File name of the sqlite database.
17748 The service's user will become the owner of the directory.
17750 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
17751 File name of the log file.
17752 The service's user will become the owner of the directory.
17754 @item @code{autoban-attempts} (default: @code{10})
17755 Maximum number of logins a user can make in @code{autoban-timeframe}
17756 without getting auto banned for @code{autoban-time}.
17758 @item @code{autoban-timeframe} (default: @code{120})
17759 Timeframe for autoban in seconds.
17761 @item @code{autoban-time} (default: @code{300})
17762 Amount of time in seconds for which a client gets banned
17763 when violating the autoban limits.
17765 @item @code{opus-threshold} (default: @code{100})
17766 Percentage of clients that need to support opus
17767 before switching over to opus audio codec.
17769 @item @code{channel-nesting-limit} (default: @code{10})
17770 How deep channels can be nested at maximum.
17772 @item @code{channelname-regex} (default: @code{#f})
17773 A string in form of a Qt regular expression that channel names must conform to.
17775 @item @code{username-regex} (default: @code{#f})
17776 A string in form of a Qt regular expression that user names must conform to.
17778 @item @code{text-message-length} (default: @code{5000})
17779 Maximum size in bytes that a user can send in one text chat message.
17781 @item @code{image-message-length} (default: @code{(* 128 1024)})
17782 Maximum size in bytes that a user can send in one image message.
17784 @item @code{cert-required?} (default: @code{#f})
17785 If it is set to @code{#t} clients that use weak password authentication
17786 will not be accepted. Users must have completed the certificate wizard to join.
17788 @item @code{remember-channel?} (default: @code{#f})
17789 Should murmur remember the last channel each user was in when they disconnected
17790 and put them into the remembered channel when they rejoin.
17792 @item @code{allow-html?} (default: @code{#f})
17793 Should html be allowed in text messages, user comments, and channel descriptions.
17795 @item @code{allow-ping?} (default: @code{#f})
17796 Setting to true exposes the current user count, the maximum user count, and
17797 the server's maximum bandwidth per client to unauthenticated users. In the
17798 Mumble client, this information is shown in the Connect dialog.
17800 Disabling this setting will prevent public listing of the server.
17802 @item @code{bonjour?} (default: @code{#f})
17803 Should the server advertise itself in the local network through the bonjour protocol.
17805 @item @code{send-version?} (default: @code{#f})
17806 Should the murmur server version be exposed in ping requests.
17808 @item @code{log-days} (default: @code{31})
17809 Murmur also stores logs in the database, which are accessible via RPC.
17810 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
17811 or -1 to disable logging to the database.
17813 @item @code{obfuscate-ips?} (default: @code{#t})
17814 Should logged ips be obfuscated to protect the privacy of users.
17816 @item @code{ssl-cert} (default: @code{#f})
17817 File name of the SSL/TLS certificate used for encrypted connections.
17820 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
17822 @item @code{ssl-key} (default: @code{#f})
17823 Filepath to the ssl private key used for encrypted connections.
17825 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
17828 @item @code{ssl-dh-params} (default: @code{#f})
17829 File name of a PEM-encoded file with Diffie-Hellman parameters
17830 for the SSL/TLS encryption. Alternatively you set it to
17831 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
17832 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
17834 @item @code{ssl-ciphers} (default: @code{#f})
17835 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
17838 This option is specified using
17839 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
17840 OpenSSL cipher list notation}.
17842 It is recommended that you try your cipher string using 'openssl ciphers <string>'
17843 before setting it here, to get a feel for which cipher suites you will get.
17844 After setting this option, it is recommend that you inspect your Murmur log
17845 to ensure that Murmur is using the cipher suites that you expected it to.
17847 Note: Changing this option may impact the backwards compatibility of your
17848 Murmur server, and can remove the ability for older Mumble clients to be able
17851 @item @code{public-registration} (default: @code{#f})
17852 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
17854 You can optionally register your server in the public server list that the
17855 @code{mumble} client shows on startup.
17856 You cannot register your server if you have set a @code{server-password},
17857 or set @code{allow-ping} to @code{#f}.
17859 It might take a few hours until it shows up in the public list.
17861 @item @code{file} (default: @code{#f})
17862 Optional alternative override for this configuration.
17866 @deftp {Data Type} murmur-public-registration-configuration
17867 Configuration for public registration of a murmur service.
17871 This is a display name for your server. Not to be confused with the hostname.
17873 @item @code{password}
17874 A password to identify your registration.
17875 Subsequent updates will need the same password. Don't lose your password.
17878 This should be a @code{http://} or @code{https://} link to your web
17881 @item @code{hostname} (default: @code{#f})
17882 By default your server will be listed by its IP address.
17883 If it is set your server will be linked by this host name instead.
17889 @node Monitoring Services
17890 @subsection Monitoring Services
17892 @subsubheading Tailon Service
17894 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
17895 viewing and searching log files.
17897 The following example will configure the service with default values.
17898 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
17901 (service tailon-service-type)
17904 The following example customises more of the Tailon configuration,
17905 adding @command{sed} to the list of allowed commands.
17908 (service tailon-service-type
17909 (tailon-configuration
17911 (tailon-configuration-file
17912 (allowed-commands '("tail" "grep" "awk" "sed"))))))
17916 @deftp {Data Type} tailon-configuration
17917 Data type representing the configuration of Tailon.
17918 This type has the following parameters:
17921 @item @code{config-file} (default: @code{(tailon-configuration-file)})
17922 The configuration file to use for Tailon. This can be set to a
17923 @dfn{tailon-configuration-file} record value, or any gexp
17924 (@pxref{G-Expressions}).
17926 For example, to instead use a local file, the @code{local-file} function
17930 (service tailon-service-type
17931 (tailon-configuration
17932 (config-file (local-file "./my-tailon.conf"))))
17935 @item @code{package} (default: @code{tailon})
17936 The tailon package to use.
17941 @deftp {Data Type} tailon-configuration-file
17942 Data type representing the configuration options for Tailon.
17943 This type has the following parameters:
17946 @item @code{files} (default: @code{(list "/var/log")})
17947 List of files to display. The list can include strings for a single file
17948 or directory, or a list, where the first item is the name of a
17949 subsection, and the remaining items are the files or directories in that
17952 @item @code{bind} (default: @code{"localhost:8080"})
17953 Address and port to which Tailon should bind on.
17955 @item @code{relative-root} (default: @code{#f})
17956 URL path to use for Tailon, set to @code{#f} to not use a path.
17958 @item @code{allow-transfers?} (default: @code{#t})
17959 Allow downloading the log files in the web interface.
17961 @item @code{follow-names?} (default: @code{#t})
17962 Allow tailing of not-yet existent files.
17964 @item @code{tail-lines} (default: @code{200})
17965 Number of lines to read initially from each file.
17967 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
17968 Commands to allow running. By default, @code{sed} is disabled.
17970 @item @code{debug?} (default: @code{#f})
17971 Set @code{debug?} to @code{#t} to show debug messages.
17973 @item @code{wrap-lines} (default: @code{#t})
17974 Initial line wrapping state in the web interface. Set to @code{#t} to
17975 initially wrap lines (the default), or to @code{#f} to initially not
17978 @item @code{http-auth} (default: @code{#f})
17979 HTTP authentication type to use. Set to @code{#f} to disable
17980 authentication (the default). Supported values are @code{"digest"} or
17983 @item @code{users} (default: @code{#f})
17984 If HTTP authentication is enabled (see @code{http-auth}), access will be
17985 restricted to the credentials provided here. To configure users, use a
17986 list of pairs, where the first element of the pair is the username, and
17987 the 2nd element of the pair is the password.
17990 (tailon-configuration-file
17991 (http-auth "basic")
17992 (users '(("user1" . "password1")
17993 ("user2" . "password2"))))
18000 @subsubheading Darkstat Service
18002 Darkstat is a packet sniffer that captures network traffic, calculates
18003 statistics about usage, and serves reports over HTTP.
18005 @defvar {Scheme Variable} darkstat-service-type
18006 This is the service type for the
18007 @uref{https://unix4lyfe.org/darkstat/, darkstat}
18008 service, its value must be a @code{darkstat-configuration} record as in
18012 (service darkstat-service-type
18013 (darkstat-configuration
18014 (interface "eno1")))
18018 @deftp {Data Type} darkstat-configuration
18019 Data type representing the configuration of @command{darkstat}.
18022 @item @code{package} (default: @code{darkstat})
18023 The darkstat package to use.
18025 @item @code{interface}
18026 Capture traffic on the specified network interface.
18028 @item @code{port} (default: @code{"667"})
18029 Bind the web interface to the specified port.
18031 @item @code{bind-address} (default: @code{"127.0.0.1"})
18032 Bind the web interface to the specified address.
18034 @item @code{base} (default: @code{"/"})
18035 Specify the path of the base URL. This can be useful if
18036 @command{darkstat} is accessed via a reverse proxy.
18041 @subsubheading Prometheus Node Exporter Service
18043 @cindex prometheus-node-exporter
18044 The Prometheus ``node exporter'' makes hardware and operating system statistics
18045 provided by the Linux kernel available for the Prometheus monitoring system.
18046 This service should be deployed on all physical nodes and virtual machines,
18047 where monitoring these statistics is desirable.
18049 @defvar {Scheme variable} prometheus-node-exporter-service-type
18050 This is the service type for the
18051 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
18052 service, its value must be a @code{prometheus-node-exporter-configuration}
18053 record as in this example:
18056 (service prometheus-node-exporter-service-type
18057 (prometheus-node-exporter-configuration
18058 (web-listen-address ":9100")))
18062 @deftp {Data Type} prometheus-node-exporter-configuration
18063 Data type representing the configuration of @command{node_exporter}.
18066 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
18067 The prometheus-node-exporter package to use.
18069 @item @code{web-listen-address} (default: @code{":9100"})
18070 Bind the web interface to the specified address.
18075 @subsubheading Zabbix server
18076 @cindex zabbix zabbix-server
18077 Zabbix provides monitoring metrics, among others network utilization, CPU load
18078 and disk space consumption:
18081 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
18082 @item Auto-discovery of servers and network devices and interfaces.
18083 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
18084 @item Distributed monitoring with centralized web administration.
18085 @item Native high performance agents.
18086 @item SLA, and ITIL KPI metrics on reporting.
18087 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
18088 @item Remote command execution through Zabbix proxies.
18091 @c %start of fragment
18093 Available @code{zabbix-server-configuration} fields are:
18095 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
18096 The zabbix-server package.
18100 @deftypevr {@code{zabbix-server-configuration} parameter} string user
18101 User who will run the Zabbix server.
18103 Defaults to @samp{"zabbix"}.
18107 @deftypevr {@code{zabbix-server-configuration} parameter} group group
18108 Group who will run the Zabbix server.
18110 Defaults to @samp{"zabbix"}.
18114 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
18115 Database host name.
18117 Defaults to @samp{"127.0.0.1"}.
18121 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
18124 Defaults to @samp{"zabbix"}.
18128 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
18131 Defaults to @samp{"zabbix"}.
18135 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
18136 Database password. Please, use @code{include-files} with
18137 @code{DBPassword=SECRET} inside a specified file instead.
18139 Defaults to @samp{""}.
18143 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
18146 Defaults to @samp{5432}.
18150 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
18151 Specifies where log messages are written to:
18155 @code{system} - syslog.
18158 @code{file} - file specified with @code{log-file} parameter.
18161 @code{console} - standard output.
18165 Defaults to @samp{""}.
18169 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
18170 Log file name for @code{log-type} @code{file} parameter.
18172 Defaults to @samp{"/var/log/zabbix/server.log"}.
18176 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
18179 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
18183 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
18184 The location of certificate authority (CA) files for SSL server
18185 certificate verification.
18187 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
18191 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
18192 Location of SSL client certificates.
18194 Defaults to @samp{"/etc/ssl/certs"}.
18198 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
18199 Extra options will be appended to Zabbix server configuration file.
18201 Defaults to @samp{""}.
18205 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
18206 You may include individual files or all files in a directory in the
18207 configuration file.
18209 Defaults to @samp{()}.
18213 @c %end of fragment
18215 @subsubheading Zabbix agent
18216 @cindex zabbix zabbix-agent
18218 Zabbix agent gathers information for Zabbix server.
18220 @c %start of fragment
18222 Available @code{zabbix-agent-configuration} fields are:
18224 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
18225 The zabbix-agent package.
18229 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
18230 User who will run the Zabbix agent.
18232 Defaults to @samp{"zabbix"}.
18236 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
18237 Group who will run the Zabbix agent.
18239 Defaults to @samp{"zabbix"}.
18243 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
18244 Unique, case sensitive hostname which is required for active checks and
18245 must match hostname as configured on the server.
18247 Defaults to @samp{"Zabbix server"}.
18251 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
18252 Specifies where log messages are written to:
18256 @code{system} - syslog.
18259 @code{file} - file specified with @code{log-file} parameter.
18262 @code{console} - standard output.
18266 Defaults to @samp{""}.
18270 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
18271 Log file name for @code{log-type} @code{file} parameter.
18273 Defaults to @samp{"/var/log/zabbix/agent.log"}.
18277 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
18280 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
18284 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
18285 List of IP addresses, optionally in CIDR notation, or hostnames of
18286 Zabbix servers and Zabbix proxies. Incoming connections will be
18287 accepted only from the hosts listed here.
18289 Defaults to @samp{("127.0.0.1")}.
18293 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
18294 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
18295 proxies for active checks. If port is not specified, default port is
18296 used. If this parameter is not specified, active checks are disabled.
18298 Defaults to @samp{("127.0.0.1")}.
18302 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
18303 Extra options will be appended to Zabbix server configuration file.
18305 Defaults to @samp{""}.
18309 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
18310 You may include individual files or all files in a directory in the
18311 configuration file.
18313 Defaults to @samp{()}.
18317 @c %end of fragment
18319 @subsubheading Zabbix front-end
18320 @cindex zabbix zabbix-front-end
18322 This service provides a WEB interface to Zabbix server.
18324 @c %start of fragment
18326 Available @code{zabbix-front-end-configuration} fields are:
18328 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
18329 NGINX configuration.
18333 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
18334 Database host name.
18336 Defaults to @samp{"localhost"}.
18340 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
18343 Defaults to @samp{5432}.
18347 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
18350 Defaults to @samp{"zabbix"}.
18354 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
18357 Defaults to @samp{"zabbix"}.
18361 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
18362 Database password. Please, use @code{db-secret-file} instead.
18364 Defaults to @samp{""}.
18368 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
18369 Secret file which will be appended to @file{zabbix.conf.php} file. This
18370 file contains credentials for use by Zabbix front-end. You are expected
18371 to create it manually.
18373 Defaults to @samp{""}.
18377 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
18378 Zabbix server hostname.
18380 Defaults to @samp{"localhost"}.
18384 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
18385 Zabbix server port.
18387 Defaults to @samp{10051}.
18392 @c %end of fragment
18394 @node Kerberos Services
18395 @subsection Kerberos Services
18398 The @code{(gnu services kerberos)} module provides services relating to
18399 the authentication protocol @dfn{Kerberos}.
18401 @subsubheading Krb5 Service
18403 Programs using a Kerberos client library normally
18404 expect a configuration file in @file{/etc/krb5.conf}.
18405 This service generates such a file from a definition provided in the
18406 operating system declaration.
18407 It does not cause any daemon to be started.
18409 No ``keytab'' files are provided by this service---you must explicitly create them.
18410 This service is known to work with the MIT client library, @code{mit-krb5}.
18411 Other implementations have not been tested.
18413 @defvr {Scheme Variable} krb5-service-type
18414 A service type for Kerberos 5 clients.
18418 Here is an example of its use:
18420 (service krb5-service-type
18421 (krb5-configuration
18422 (default-realm "EXAMPLE.COM")
18423 (allow-weak-crypto? #t)
18426 (name "EXAMPLE.COM")
18427 (admin-server "groucho.example.com")
18428 (kdc "karl.example.com"))
18431 (admin-server "kerb-admin.argrx.edu")
18432 (kdc "keys.argrx.edu"))))))
18436 This example provides a Kerberos@tie{}5 client configuration which:
18438 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
18439 of which have distinct administration servers and key distribution centers;
18440 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
18441 specified by clients;
18442 @item Accepts services which only support encryption types known to be weak.
18445 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
18446 Only the most commonly used ones are described here.
18447 For a full list, and more detailed explanation of each, see the MIT
18448 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
18452 @deftp {Data Type} krb5-realm
18453 @cindex realm, kerberos
18456 This field is a string identifying the name of the realm.
18457 A common convention is to use the fully qualified DNS name of your organization,
18458 converted to upper case.
18460 @item @code{admin-server}
18461 This field is a string identifying the host where the administration server is
18465 This field is a string identifying the key distribution center
18470 @deftp {Data Type} krb5-configuration
18473 @item @code{allow-weak-crypto?} (default: @code{#f})
18474 If this flag is @code{#t} then services which only offer encryption algorithms
18475 known to be weak will be accepted.
18477 @item @code{default-realm} (default: @code{#f})
18478 This field should be a string identifying the default Kerberos
18479 realm for the client.
18480 You should set this field to the name of your Kerberos realm.
18481 If this value is @code{#f}
18482 then a realm must be specified with every Kerberos principal when invoking programs
18483 such as @command{kinit}.
18485 @item @code{realms}
18486 This should be a non-empty list of @code{krb5-realm} objects, which clients may
18488 Normally, one of them will have a @code{name} field matching the @code{default-realm}
18494 @subsubheading PAM krb5 Service
18497 The @code{pam-krb5} service allows for login authentication and password
18498 management via Kerberos.
18499 You will need this service if you want PAM enabled applications to authenticate
18500 users using Kerberos.
18502 @defvr {Scheme Variable} pam-krb5-service-type
18503 A service type for the Kerberos 5 PAM module.
18506 @deftp {Data Type} pam-krb5-configuration
18507 Data type representing the configuration of the Kerberos 5 PAM module.
18508 This type has the following parameters:
18510 @item @code{pam-krb5} (default: @code{pam-krb5})
18511 The pam-krb5 package to use.
18513 @item @code{minimum-uid} (default: @code{1000})
18514 The smallest user ID for which Kerberos authentications should be attempted.
18515 Local accounts with lower values will silently fail to authenticate.
18520 @node LDAP Services
18521 @subsection LDAP Services
18523 @cindex nslcd, LDAP service
18525 The @code{(gnu services authentication)} module provides the
18526 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
18527 server. In addition to configuring the service itself, you may want to add
18528 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
18529 Switch} for detailed information.
18531 Here is a simple operating system declaration with a default configuration of
18532 the @code{nslcd-service-type} and a Name Service Switch configuration that
18533 consults the @code{ldap} name service last:
18536 (use-service-modules authentication)
18537 (use-modules (gnu system nss))
18543 (service nslcd-service-type)
18544 (service dhcp-client-service-type)
18546 (name-service-switch
18547 (let ((services (list (name-service (name "db"))
18548 (name-service (name "files"))
18549 (name-service (name "ldap")))))
18550 (name-service-switch
18551 (inherit %mdns-host-lookup-nss)
18552 (password services)
18555 (netgroup services)
18556 (gshadow services)))))
18559 @c %start of generated documentation for nslcd-configuration
18561 Available @code{nslcd-configuration} fields are:
18563 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
18564 The @code{nss-pam-ldapd} package to use.
18568 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
18569 The number of threads to start that can handle requests and perform LDAP
18570 queries. Each thread opens a separate connection to the LDAP server.
18571 The default is to start 5 threads.
18573 Defaults to @samp{disabled}.
18577 @deftypevr {@code{nslcd-configuration} parameter} string uid
18578 This specifies the user id with which the daemon should be run.
18580 Defaults to @samp{"nslcd"}.
18584 @deftypevr {@code{nslcd-configuration} parameter} string gid
18585 This specifies the group id with which the daemon should be run.
18587 Defaults to @samp{"nslcd"}.
18591 @deftypevr {@code{nslcd-configuration} parameter} log-option log
18592 This option controls the way logging is done via a list containing
18593 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
18594 or "syslog", or an absolute file name. The LEVEL argument is optional
18595 and specifies the log level. The log level may be one of the following
18596 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
18597 messages with the specified log level or higher are logged.
18599 Defaults to @samp{("/var/log/nslcd" info)}.
18603 @deftypevr {@code{nslcd-configuration} parameter} list uri
18604 The list of LDAP server URIs. Normally, only the first server will be
18605 used with the following servers as fall-back.
18607 Defaults to @samp{("ldap://localhost:389/")}.
18611 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
18612 The version of the LDAP protocol to use. The default is to use the
18613 maximum version supported by the LDAP library.
18615 Defaults to @samp{disabled}.
18619 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
18620 Specifies the distinguished name with which to bind to the directory
18621 server for lookups. The default is to bind anonymously.
18623 Defaults to @samp{disabled}.
18627 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
18628 Specifies the credentials with which to bind. This option is only
18629 applicable when used with binddn.
18631 Defaults to @samp{disabled}.
18635 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
18636 Specifies the distinguished name to use when the root user tries to
18637 modify a user's password using the PAM module.
18639 Defaults to @samp{disabled}.
18643 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
18644 Specifies the credentials with which to bind if the root user tries to
18645 change a user's password. This option is only applicable when used with
18648 Defaults to @samp{disabled}.
18652 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
18653 Specifies the SASL mechanism to be used when performing SASL
18656 Defaults to @samp{disabled}.
18660 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
18661 Specifies the SASL realm to be used when performing SASL authentication.
18663 Defaults to @samp{disabled}.
18667 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
18668 Specifies the authentication identity to be used when performing SASL
18671 Defaults to @samp{disabled}.
18675 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
18676 Specifies the authorization identity to be used when performing SASL
18679 Defaults to @samp{disabled}.
18683 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
18684 Determines whether the LDAP server host name should be canonicalised. If
18685 this is enabled the LDAP library will do a reverse host name lookup. By
18686 default, it is left up to the LDAP library whether this check is
18689 Defaults to @samp{disabled}.
18693 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
18694 Set the name for the GSS-API Kerberos credentials cache.
18696 Defaults to @samp{disabled}.
18700 @deftypevr {@code{nslcd-configuration} parameter} string base
18701 The directory search base.
18703 Defaults to @samp{"dc=example,dc=com"}.
18707 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
18708 Specifies the search scope (subtree, onelevel, base or children). The
18709 default scope is subtree; base scope is almost never useful for name
18710 service lookups; children scope is not supported on all servers.
18712 Defaults to @samp{(subtree)}.
18716 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
18717 Specifies the policy for dereferencing aliases. The default policy is
18718 to never dereference aliases.
18720 Defaults to @samp{disabled}.
18724 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
18725 Specifies whether automatic referral chasing should be enabled. The
18726 default behaviour is to chase referrals.
18728 Defaults to @samp{disabled}.
18732 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
18733 This option allows for custom attributes to be looked up instead of the
18734 default RFC 2307 attributes. It is a list of maps, each consisting of
18735 the name of a map, the RFC 2307 attribute to match and the query
18736 expression for the attribute as it is available in the directory.
18738 Defaults to @samp{()}.
18742 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
18743 A list of filters consisting of the name of a map to which the filter
18744 applies and an LDAP search filter expression.
18746 Defaults to @samp{()}.
18750 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
18751 Specifies the time limit in seconds to use when connecting to the
18752 directory server. The default value is 10 seconds.
18754 Defaults to @samp{disabled}.
18758 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
18759 Specifies the time limit (in seconds) to wait for a response from the
18760 LDAP server. A value of zero, which is the default, is to wait
18761 indefinitely for searches to be completed.
18763 Defaults to @samp{disabled}.
18767 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
18768 Specifies the period if inactivity (in seconds) after which the con‐
18769 nection to the LDAP server will be closed. The default is not to time
18772 Defaults to @samp{disabled}.
18776 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
18777 Specifies the number of seconds to sleep when connecting to all LDAP
18778 servers fails. By default one second is waited between the first
18779 failure and the first retry.
18781 Defaults to @samp{disabled}.
18785 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
18786 Specifies the time after which the LDAP server is considered to be
18787 permanently unavailable. Once this time is reached retries will be done
18788 only once per this time period. The default value is 10 seconds.
18790 Defaults to @samp{disabled}.
18794 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
18795 Specifies whether to use SSL/TLS or not (the default is not to). If
18796 'start-tls is specified then StartTLS is used rather than raw LDAP over
18799 Defaults to @samp{disabled}.
18803 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
18804 Specifies what checks to perform on a server-supplied certificate. The
18805 meaning of the values is described in the ldap.conf(5) manual page.
18807 Defaults to @samp{disabled}.
18811 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
18812 Specifies the directory containing X.509 certificates for peer authen‐
18813 tication. This parameter is ignored when using GnuTLS.
18815 Defaults to @samp{disabled}.
18819 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
18820 Specifies the path to the X.509 certificate for peer authentication.
18822 Defaults to @samp{disabled}.
18826 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
18827 Specifies the path to an entropy source. This parameter is ignored when
18830 Defaults to @samp{disabled}.
18834 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
18835 Specifies the ciphers to use for TLS as a string.
18837 Defaults to @samp{disabled}.
18841 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
18842 Specifies the path to the file containing the local certificate for
18843 client TLS authentication.
18845 Defaults to @samp{disabled}.
18849 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
18850 Specifies the path to the file containing the private key for client TLS
18853 Defaults to @samp{disabled}.
18857 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
18858 Set this to a number greater than 0 to request paged results from the
18859 LDAP server in accordance with RFC2696. The default (0) is to not
18860 request paged results.
18862 Defaults to @samp{disabled}.
18866 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
18867 This option prevents group membership lookups through LDAP for the
18868 specified users. Alternatively, the value 'all-local may be used. With
18869 that value nslcd builds a full list of non-LDAP users on startup.
18871 Defaults to @samp{disabled}.
18875 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
18876 This option ensures that LDAP users with a numeric user id lower than
18877 the specified value are ignored.
18879 Defaults to @samp{disabled}.
18883 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
18884 This option specifies an offset that is added to all LDAP numeric user
18885 ids. This can be used to avoid user id collisions with local users.
18887 Defaults to @samp{disabled}.
18891 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
18892 This option specifies an offset that is added to all LDAP numeric group
18893 ids. This can be used to avoid user id collisions with local groups.
18895 Defaults to @samp{disabled}.
18899 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
18900 If this option is set, the member attribute of a group may point to
18901 another group. Members of nested groups are also returned in the higher
18902 level group and parent groups are returned when finding groups for a
18903 specific user. The default is not to perform extra searches for nested
18906 Defaults to @samp{disabled}.
18910 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
18911 If this option is set, the group member list is not retrieved when
18912 looking up groups. Lookups for finding which groups a user belongs to
18913 will remain functional so the user will likely still get the correct
18914 groups assigned on login.
18916 Defaults to @samp{disabled}.
18920 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
18921 If this option is set, functions which cause all user/group entries to
18922 be loaded from the directory will not succeed in doing so. This can
18923 dramatically reduce LDAP server load in situations where there are a
18924 great number of users and/or groups. This option is not recommended for
18925 most configurations.
18927 Defaults to @samp{disabled}.
18931 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
18932 This option can be used to specify how user and group names are verified
18933 within the system. This pattern is used to check all user and group
18934 names that are requested and returned from LDAP.
18936 Defaults to @samp{disabled}.
18940 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
18941 This specifies whether or not to perform searches using case-insensitive
18942 matching. Enabling this could open up the system to authorization
18943 bypass vulnerabilities and introduce nscd cache poisoning
18944 vulnerabilities which allow denial of service.
18946 Defaults to @samp{disabled}.
18950 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
18951 This option specifies whether password policy controls are requested and
18952 handled from the LDAP server when performing user authentication.
18954 Defaults to @samp{disabled}.
18958 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
18959 By default nslcd performs an LDAP search with the user's credentials
18960 after BIND (authentication) to ensure that the BIND operation was
18961 successful. The default search is a simple check to see if the user's
18962 DN exists. A search filter can be specified that will be used instead.
18963 It should return at least one entry.
18965 Defaults to @samp{disabled}.
18969 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
18970 This option allows flexible fine tuning of the authorisation check that
18971 should be performed. The search filter specified is executed and if any
18972 entries match, access is granted, otherwise access is denied.
18974 Defaults to @samp{disabled}.
18978 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
18979 If this option is set password modification using pam_ldap will be
18980 denied and the specified message will be presented to the user instead.
18981 The message can be used to direct the user to an alternative means of
18982 changing their password.
18984 Defaults to @samp{disabled}.
18988 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
18989 List of pam service names for which LDAP authentication should suffice.
18991 Defaults to @samp{()}.
18995 @c %end of generated documentation for nslcd-configuration
18999 @subsection Web Services
19004 The @code{(gnu services web)} module provides the Apache HTTP Server,
19005 the nginx web server, and also a fastcgi wrapper daemon.
19007 @subsubheading Apache HTTP Server
19009 @deffn {Scheme Variable} httpd-service-type
19010 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
19011 (@dfn{httpd}). The value for this service type is a
19012 @code{httpd-configuration} record.
19014 A simple example configuration is given below.
19017 (service httpd-service-type
19018 (httpd-configuration
19021 (server-name "www.example.com")
19022 (document-root "/srv/http/www.example.com")))))
19025 Other services can also extend the @code{httpd-service-type} to add to
19029 (simple-service 'my-extra-server httpd-service-type
19033 (list (string-append
19034 "ServerName "www.example.com
19035 DocumentRoot \"/srv/http/www.example.com\"")))))
19039 The details for the @code{httpd-configuration}, @code{httpd-module},
19040 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
19043 @deffn {Data Type} httpd-configuration
19044 This data type represents the configuration for the httpd service.
19047 @item @code{package} (default: @code{httpd})
19048 The httpd package to use.
19050 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19051 The pid file used by the shepherd-service.
19053 @item @code{config} (default: @code{(httpd-config-file)})
19054 The configuration file to use with the httpd service. The default value
19055 is a @code{httpd-config-file} record, but this can also be a different
19056 G-expression that generates a file, for example a @code{plain-file}. A
19057 file outside of the store can also be specified through a string.
19062 @deffn {Data Type} httpd-module
19063 This data type represents a module for the httpd service.
19067 The name of the module.
19070 The file for the module. This can be relative to the httpd package being
19071 used, the absolute location of a file, or a G-expression for a file
19072 within the store, for example @code{(file-append mod-wsgi
19073 "/modules/mod_wsgi.so")}.
19078 @defvr {Scheme Variable} %default-httpd-modules
19079 A default list of @code{httpd-module} objects.
19082 @deffn {Data Type} httpd-config-file
19083 This data type represents a configuration file for the httpd service.
19086 @item @code{modules} (default: @code{%default-httpd-modules})
19087 The modules to load. Additional modules can be added here, or loaded by
19088 additional configuration.
19090 For example, in order to handle requests for PHP files, you can use Apache’s
19091 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
19094 (service httpd-service-type
19095 (httpd-configuration
19100 (name "proxy_module")
19101 (file "modules/mod_proxy.so"))
19103 (name "proxy_fcgi_module")
19104 (file "modules/mod_proxy_fcgi.so"))
19105 %default-httpd-modules))
19106 (extra-config (list "\
19107 <FilesMatch \\.php$>
19108 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
19109 </FilesMatch>"))))))
19110 (service php-fpm-service-type
19111 (php-fpm-configuration
19112 (socket "/var/run/php-fpm.sock")
19113 (socket-group "httpd")))
19116 @item @code{server-root} (default: @code{httpd})
19117 The @code{ServerRoot} in the configuration file, defaults to the httpd
19118 package. Directives including @code{Include} and @code{LoadModule} are
19119 taken as relative to the server root.
19121 @item @code{server-name} (default: @code{#f})
19122 The @code{ServerName} in the configuration file, used to specify the
19123 request scheme, hostname and port that the server uses to identify
19126 This doesn't need to be set in the server config, and can be specifyed
19127 in virtual hosts. The default is @code{#f} to not specify a
19130 @item @code{document-root} (default: @code{"/srv/http"})
19131 The @code{DocumentRoot} from which files will be served.
19133 @item @code{listen} (default: @code{'("80")})
19134 The list of values for the @code{Listen} directives in the config
19135 file. The value should be a list of strings, when each string can
19136 specify the port number to listen on, and optionally the IP address and
19139 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19140 The @code{PidFile} to use. This should match the @code{pid-file} set in
19141 the @code{httpd-configuration} so that the Shepherd service is
19142 configured correctly.
19144 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
19145 The @code{ErrorLog} to which the server will log errors.
19147 @item @code{user} (default: @code{"httpd"})
19148 The @code{User} which the server will answer requests as.
19150 @item @code{group} (default: @code{"httpd"})
19151 The @code{Group} which the server will answer requests as.
19153 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
19154 A flat list of strings and G-expressions which will be added to the end
19155 of the configuration file.
19157 Any values which the service is extended with will be appended to this
19163 @deffn {Data Type} httpd-virtualhost
19164 This data type represents a virtualhost configuration block for the httpd service.
19166 These should be added to the extra-config for the httpd-service.
19169 (simple-service 'my-extra-server httpd-service-type
19173 (list (string-append
19174 "ServerName "www.example.com
19175 DocumentRoot \"/srv/http/www.example.com\"")))))
19179 @item @code{addresses-and-ports}
19180 The addresses and ports for the @code{VirtualHost} directive.
19182 @item @code{contents}
19183 The contents of the @code{VirtualHost} directive, this should be a list
19184 of strings and G-expressions.
19189 @subsubheading NGINX
19191 @deffn {Scheme Variable} nginx-service-type
19192 Service type for the @uref{https://nginx.org/,NGinx} web server. The
19193 value for this service type is a @code{<nginx-configuration>} record.
19195 A simple example configuration is given below.
19198 (service nginx-service-type
19199 (nginx-configuration
19201 (list (nginx-server-configuration
19202 (server-name '("www.example.com"))
19203 (root "/srv/http/www.example.com"))))))
19206 In addition to adding server blocks to the service configuration
19207 directly, this service can be extended by other services to add server
19208 blocks, as in this example:
19211 (simple-service 'my-extra-server nginx-service-type
19212 (list (nginx-server-configuration
19213 (root "/srv/http/extra-website")
19214 (try-files (list "$uri" "$uri/index.html")))))
19218 At startup, @command{nginx} has not yet read its configuration file, so
19219 it uses a default file to log error messages. If it fails to load its
19220 configuration file, that is where error messages are logged. After the
19221 configuration file is loaded, the default error log file changes as per
19222 configuration. In our case, startup error messages can be found in
19223 @file{/var/run/nginx/logs/error.log}, and after configuration in
19224 @file{/var/log/nginx/error.log}. The second location can be changed
19225 with the @var{log-directory} configuration option.
19227 @deffn {Data Type} nginx-configuration
19228 This data type represents the configuration for NGinx. Some
19229 configuration can be done through this and the other provided record
19230 types, or alternatively, a config file can be provided.
19233 @item @code{nginx} (default: @code{nginx})
19234 The nginx package to use.
19236 @item @code{log-directory} (default: @code{"/var/log/nginx"})
19237 The directory to which NGinx will write log files.
19239 @item @code{run-directory} (default: @code{"/var/run/nginx"})
19240 The directory in which NGinx will create a pid file, and write temporary
19243 @item @code{server-blocks} (default: @code{'()})
19244 A list of @dfn{server blocks} to create in the generated configuration
19245 file, the elements should be of type
19246 @code{<nginx-server-configuration>}.
19248 The following example would setup NGinx to serve @code{www.example.com}
19249 from the @code{/srv/http/www.example.com} directory, without using
19252 (service nginx-service-type
19253 (nginx-configuration
19255 (list (nginx-server-configuration
19256 (server-name '("www.example.com"))
19257 (root "/srv/http/www.example.com"))))))
19260 @item @code{upstream-blocks} (default: @code{'()})
19261 A list of @dfn{upstream blocks} to create in the generated configuration
19262 file, the elements should be of type
19263 @code{<nginx-upstream-configuration>}.
19265 Configuring upstreams through the @code{upstream-blocks} can be useful
19266 when combined with @code{locations} in the
19267 @code{<nginx-server-configuration>} records. The following example
19268 creates a server configuration with one location configuration, that
19269 will proxy requests to a upstream configuration, which will handle
19270 requests with two servers.
19275 (nginx-configuration
19277 (list (nginx-server-configuration
19278 (server-name '("www.example.com"))
19279 (root "/srv/http/www.example.com")
19282 (nginx-location-configuration
19284 (body '("proxy_pass http://server-proxy;"))))))))
19286 (list (nginx-upstream-configuration
19287 (name "server-proxy")
19288 (servers (list "server1.example.com"
19289 "server2.example.com")))))))
19292 @item @code{file} (default: @code{#f})
19293 If a configuration @var{file} is provided, this will be used, rather than
19294 generating a configuration file from the provided @code{log-directory},
19295 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
19296 proper operation, these arguments should match what is in @var{file} to ensure
19297 that the directories are created when the service is activated.
19299 This can be useful if you have an existing configuration file, or it's
19300 not possible to do what is required through the other parts of the
19301 nginx-configuration record.
19303 @item @code{server-names-hash-bucket-size} (default: @code{#f})
19304 Bucket size for the server names hash tables, defaults to @code{#f} to
19305 use the size of the processors cache line.
19307 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
19308 Maximum bucket size for the server names hash tables.
19310 @item @code{extra-content} (default: @code{""})
19311 Extra content for the @code{http} block. Should be string or a string
19312 valued G-expression.
19317 @deftp {Data Type} nginx-server-configuration
19318 Data type representing the configuration of an nginx server block.
19319 This type has the following parameters:
19322 @item @code{listen} (default: @code{'("80" "443 ssl")})
19323 Each @code{listen} directive sets the address and port for IP, or the
19324 path for a UNIX-domain socket on which the server will accept requests.
19325 Both address and port, or only address or only port can be specified.
19326 An address may also be a hostname, for example:
19329 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
19332 @item @code{server-name} (default: @code{(list 'default)})
19333 A list of server names this server represents. @code{'default} represents the
19334 default server for connections matching no other server.
19336 @item @code{root} (default: @code{"/srv/http"})
19337 Root of the website nginx will serve.
19339 @item @code{locations} (default: @code{'()})
19340 A list of @dfn{nginx-location-configuration} or
19341 @dfn{nginx-named-location-configuration} records to use within this
19344 @item @code{index} (default: @code{(list "index.html")})
19345 Index files to look for when clients ask for a directory. If it cannot be found,
19346 Nginx will send the list of files in the directory.
19348 @item @code{try-files} (default: @code{'()})
19349 A list of files whose existence is checked in the specified order.
19350 @code{nginx} will use the first file it finds to process the request.
19352 @item @code{ssl-certificate} (default: @code{#f})
19353 Where to find the certificate for secure connections. Set it to @code{#f} if
19354 you don't have a certificate or you don't want to use HTTPS.
19356 @item @code{ssl-certificate-key} (default: @code{#f})
19357 Where to find the private key for secure connections. Set it to @code{#f} if
19358 you don't have a key or you don't want to use HTTPS.
19360 @item @code{server-tokens?} (default: @code{#f})
19361 Whether the server should add its configuration to response.
19363 @item @code{raw-content} (default: @code{'()})
19364 A list of raw lines added to the server block.
19369 @deftp {Data Type} nginx-upstream-configuration
19370 Data type representing the configuration of an nginx @code{upstream}
19371 block. This type has the following parameters:
19375 Name for this group of servers.
19377 @item @code{servers}
19378 Specify the addresses of the servers in the group. The address can be
19379 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
19380 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
19381 prefix @samp{unix:}. For addresses using an IP address or domain name,
19382 the default port is 80, and a different port can be specified
19388 @deftp {Data Type} nginx-location-configuration
19389 Data type representing the configuration of an nginx @code{location}
19390 block. This type has the following parameters:
19394 URI which this location block matches.
19396 @anchor{nginx-location-configuration body}
19398 Body of the location block, specified as a list of strings. This can contain
19400 configuration directives. For example, to pass requests to a upstream
19401 server group defined using an @code{nginx-upstream-configuration} block,
19402 the following directive would be specified in the body @samp{(list "proxy_pass
19403 http://upstream-name;")}.
19408 @deftp {Data Type} nginx-named-location-configuration
19409 Data type representing the configuration of an nginx named location
19410 block. Named location blocks are used for request redirection, and not
19411 used for regular request processing. This type has the following
19416 Name to identify this location block.
19419 @xref{nginx-location-configuration body}, as the body for named location
19420 blocks can be used in a similar way to the
19421 @code{nginx-location-configuration body}. One restriction is that the
19422 body of a named location block cannot contain location blocks.
19427 @subsubheading Varnish Cache
19429 Varnish is a fast cache server that sits in between web applications
19430 and end users. It proxies requests from clients and caches the
19431 accessed URLs such that multiple requests for the same resource only
19432 creates one request to the back-end.
19434 @defvr {Scheme Variable} varnish-service-type
19435 Service type for the Varnish daemon.
19438 @deftp {Data Type} varnish-configuration
19439 Data type representing the @code{varnish} service configuration.
19440 This type has the following parameters:
19443 @item @code{package} (default: @code{varnish})
19444 The Varnish package to use.
19446 @item @code{name} (default: @code{"default"})
19447 A name for this Varnish instance. Varnish will create a directory in
19448 @file{/var/varnish/} with this name and keep temporary files there. If
19449 the name starts with a forward slash, it is interpreted as an absolute
19452 Pass the @code{-n} argument to other Varnish programs to connect to the
19453 named instance, e.g.@: @command{varnishncsa -n default}.
19455 @item @code{backend} (default: @code{"localhost:8080"})
19456 The backend to use. This option has no effect if @code{vcl} is set.
19458 @item @code{vcl} (default: #f)
19459 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
19460 is @code{#f}, Varnish will proxy @code{backend} using the default
19461 configuration. Otherwise this must be a file-like object with valid
19464 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
19465 For example, to mirror @url{http://www.gnu.org,www.gnu.org} with VCL you
19466 can do something along these lines:
19469 (define %gnu-mirror
19473 backend gnu @{ .host = "www.gnu.org"; @}"))
19477 (services (cons (service varnish-service-type
19478 (varnish-configuration
19480 (vcl %gnu-mirror)))
19484 The configuration of an already running Varnish instance can be inspected
19485 and changed using the @command{varnishadm} program.
19487 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
19488 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
19489 comprehensive documentation on Varnish and its configuration language.
19491 @item @code{listen} (default: @code{'("localhost:80")})
19492 List of addresses Varnish will listen on.
19494 @item @code{storage} (default: @code{'("malloc,128m")})
19495 List of storage backends that will be available in VCL.
19497 @item @code{parameters} (default: @code{'()})
19498 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
19500 @item @code{extra-options} (default: @code{'()})
19501 Additional arguments to pass to the @command{varnishd} process.
19506 @subsubheading Patchwork
19508 Patchwork is a patch tracking system. It can collect patches sent to a
19509 mailing list, and display them in a web interface.
19511 @defvr {Scheme Variable} patchwork-service-type
19512 Service type for Patchwork.
19515 The following example is an example of a minimal service for Patchwork, for
19516 the @code{patchwork.example.com} domain.
19519 (service patchwork-service-type
19520 (patchwork-configuration
19521 (domain "patchwork.example.com")
19523 (patchwork-settings-module
19524 (allowed-hosts (list domain))
19525 (default-from-email "patchwork@@patchwork.example.com")))
19526 (getmail-retriever-config
19527 (getmail-retriever-configuration
19528 (type "SimpleIMAPSSLRetriever")
19529 (server "imap.example.com")
19531 (username "patchwork")
19533 (list (file-append coreutils "/bin/cat")
19534 "/etc/getmail-patchwork-imap-password"))
19536 '((mailboxes . ("Patches"))))))))
19540 There are three records for configuring the Patchwork service. The
19541 @code{<patchwork-configuration>} relates to the configuration for Patchwork
19542 within the HTTPD service.
19544 The @code{settings-module} field within the @code{<patchwork-configuration>}
19545 record can be populated with the @code{<patchwork-settings-module>} record,
19546 which describes a settings module that is generated within the Guix store.
19548 For the @code{database-configuration} field within the
19549 @code{<patchwork-settings-module>}, the
19550 @code{<patchwork-database-configuration>} must be used.
19552 @deftp {Data Type} patchwork-configuration
19553 Data type representing the Patchwork service configuration. This type has the
19554 following parameters:
19557 @item @code{patchwork} (default: @code{patchwork})
19558 The Patchwork package to use.
19560 @item @code{domain}
19561 The domain to use for Patchwork, this is used in the HTTPD service virtual
19564 @item @code{settings-module}
19565 The settings module to use for Patchwork. As a Django application, Patchwork
19566 is configured with a Python module containing the settings. This can either be
19567 an instance of the @code{<patchwork-settings-module>} record, any other record
19568 that represents the settings in the store, or a directory outside of the
19571 @item @code{static-path} (default: @code{"/static/"})
19572 The path under which the HTTPD service should serve the static files.
19574 @item @code{getmail-retriever-config}
19575 The getmail-retriever-configuration record value to use with
19576 Patchwork. Getmail will be configured with this value, the messages will be
19577 delivered to Patchwork.
19582 @deftp {Data Type} patchwork-settings-module
19583 Data type representing a settings module for Patchwork. Some of these
19584 settings relate directly to Patchwork, but others relate to Django, the web
19585 framework used by Patchwork, or the Django Rest Framework library. This type
19586 has the following parameters:
19589 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
19590 The database connection settings used for Patchwork. See the
19591 @code{<patchwork-database-configuration>} record type for more information.
19593 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
19594 Patchwork, as a Django web application uses a secret key for cryptographically
19595 signing values. This file should contain a unique unpredictable value.
19597 If this file does not exist, it will be created and populated with a random
19598 value by the patchwork-setup shepherd service.
19600 This setting relates to Django.
19602 @item @code{allowed-hosts}
19603 A list of valid hosts for this Patchwork service. This should at least include
19604 the domain specified in the @code{<patchwork-configuration>} record.
19606 This is a Django setting.
19608 @item @code{default-from-email}
19609 The email address from which Patchwork should send email by default.
19611 This is a Patchwork setting.
19613 @item @code{static-url} (default: @code{#f})
19614 The URL to use when serving static assets. It can be part of a URL, or a full
19615 URL, but must end in a @code{/}.
19617 If the default value is used, the @code{static-path} value from the
19618 @code{<patchwork-configuration>} record will be used.
19620 This is a Django setting.
19622 @item @code{admins} (default: @code{'()})
19623 Email addresses to send the details of errors that occur. Each value should
19624 be a list containing two elements, the name and then the email address.
19626 This is a Django setting.
19628 @item @code{debug?} (default: @code{#f})
19629 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
19630 messages will be shown.
19632 This is a Django setting.
19634 @item @code{enable-rest-api?} (default: @code{#t})
19635 Whether to enable the Patchwork REST API.
19637 This is a Patchwork setting.
19639 @item @code{enable-xmlrpc?} (default: @code{#t})
19640 Whether to enable the XML RPC API.
19642 This is a Patchwork setting.
19644 @item @code{force-https-links?} (default: @code{#t})
19645 Whether to use HTTPS links on Patchwork pages.
19647 This is a Patchwork setting.
19649 @item @code{extra-settings} (default: @code{""})
19650 Extra code to place at the end of the Patchwork settings module.
19655 @deftp {Data Type} patchwork-database-configuration
19656 Data type representing the database configuration for Patchwork.
19659 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
19660 The database engine to use.
19662 @item @code{name} (default: @code{"patchwork"})
19663 The name of the database to use.
19665 @item @code{user} (default: @code{"httpd"})
19666 The user to connect to the database as.
19668 @item @code{password} (default: @code{""})
19669 The password to use when connecting to the database.
19671 @item @code{host} (default: @code{""})
19672 The host to make the database connection to.
19674 @item @code{port} (default: @code{""})
19675 The port on which to connect to the database.
19680 @subsubheading FastCGI
19683 FastCGI is an interface between the front-end and the back-end of a web
19684 service. It is a somewhat legacy facility; new web services should
19685 generally just talk HTTP between the front-end and the back-end.
19686 However there are a number of back-end services such as PHP or the
19687 optimized HTTP Git repository access that use FastCGI, so we have
19688 support for it in Guix.
19690 To use FastCGI, you configure the front-end web server (e.g., nginx) to
19691 dispatch some subset of its requests to the fastcgi backend, which
19692 listens on a local TCP or UNIX socket. There is an intermediary
19693 @code{fcgiwrap} program that sits between the actual backend process and
19694 the web server. The front-end indicates which backend program to run,
19695 passing that information to the @code{fcgiwrap} process.
19697 @defvr {Scheme Variable} fcgiwrap-service-type
19698 A service type for the @code{fcgiwrap} FastCGI proxy.
19701 @deftp {Data Type} fcgiwrap-configuration
19702 Data type representing the configuration of the @code{fcgiwrap} service.
19703 This type has the following parameters:
19705 @item @code{package} (default: @code{fcgiwrap})
19706 The fcgiwrap package to use.
19708 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
19709 The socket on which the @code{fcgiwrap} process should listen, as a
19710 string. Valid @var{socket} values include
19711 @code{unix:@var{/path/to/unix/socket}},
19712 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
19713 @code{tcp6:[@var{ipv6_addr}]:port}.
19715 @item @code{user} (default: @code{fcgiwrap})
19716 @itemx @code{group} (default: @code{fcgiwrap})
19717 The user and group names, as strings, under which to run the
19718 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
19719 the user asks for the specific user or group names @code{fcgiwrap} that
19720 the corresponding user and/or group is present on the system.
19722 It is possible to configure a FastCGI-backed web service to pass HTTP
19723 authentication information from the front-end to the back-end, and to
19724 allow @code{fcgiwrap} to run the back-end process as a corresponding
19725 local user. To enable this capability on the back-end., run
19726 @code{fcgiwrap} as the @code{root} user and group. Note that this
19727 capability also has to be configured on the front-end as well.
19732 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
19733 with some additional features useful for sites of any size.
19735 These features include:
19737 @item Adaptive process spawning
19738 @item Basic statistics (similar to Apache's mod_status)
19739 @item Advanced process management with graceful stop/start
19740 @item Ability to start workers with different uid/gid/chroot/environment
19741 and different php.ini (replaces safe_mode)
19742 @item Stdout & stderr logging
19743 @item Emergency restart in case of accidental opcode cache destruction
19744 @item Accelerated upload support
19745 @item Support for a "slowlog"
19746 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
19747 a special function to finish request & flush all data while continuing to do
19748 something time-consuming (video converting, stats processing, etc.)
19750 ...@: and much more.
19752 @defvr {Scheme Variable} php-fpm-service-type
19753 A Service type for @code{php-fpm}.
19756 @deftp {Data Type} php-fpm-configuration
19757 Data Type for php-fpm service configuration.
19759 @item @code{php} (default: @code{php})
19760 The php package to use.
19761 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
19762 The address on which to accept FastCGI requests. Valid syntaxes are:
19764 @item @code{"ip.add.re.ss:port"}
19765 Listen on a TCP socket to a specific address on a specific port.
19766 @item @code{"port"}
19767 Listen on a TCP socket to all addresses on a specific port.
19768 @item @code{"/path/to/unix/socket"}
19769 Listen on a unix socket.
19772 @item @code{user} (default: @code{php-fpm})
19773 User who will own the php worker processes.
19774 @item @code{group} (default: @code{php-fpm})
19775 Group of the worker processes.
19776 @item @code{socket-user} (default: @code{php-fpm})
19777 User who can speak to the php-fpm socket.
19778 @item @code{socket-group} (default: @code{php-fpm})
19779 Group that can speak to the php-fpm socket.
19780 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
19781 The process id of the php-fpm process is written to this file
19782 once the service has started.
19783 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
19784 Log for the php-fpm master process.
19785 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
19786 Detailed settings for the php-fpm process manager.
19789 @item @code{<php-fpm-dynamic-process-manager-configuration>}
19790 @item @code{<php-fpm-static-process-manager-configuration>}
19791 @item @code{<php-fpm-on-demand-process-manager-configuration>}
19793 @item @code{display-errors} (default @code{#f})
19794 Determines whether php errors and warning should be sent to clients
19795 and displayed in their browsers.
19796 This is useful for local php development, but a security risk for public sites,
19797 as error messages can reveal passwords and personal data.
19798 @item @code{timezone} (default @code{#f})
19799 Specifies @code{php_admin_value[date.timezone]} parameter.
19800 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
19801 This file will log the @code{stderr} outputs of php worker processes.
19802 Can be set to @code{#f} to disable logging.
19803 @item @code{file} (default @code{#f})
19804 An optional override of the whole configuration.
19805 You can use the @code{mixed-text-file} function or an absolute filepath for it.
19809 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
19810 Data Type for the @code{dynamic} php-fpm process manager. With the
19811 @code{dynamic} process manager, spare worker processes are kept around
19812 based on it's configured limits.
19814 @item @code{max-children} (default: @code{5})
19815 Maximum of worker processes.
19816 @item @code{start-servers} (default: @code{2})
19817 How many worker processes should be started on start-up.
19818 @item @code{min-spare-servers} (default: @code{1})
19819 How many spare worker processes should be kept around at minimum.
19820 @item @code{max-spare-servers} (default: @code{3})
19821 How many spare worker processes should be kept around at maximum.
19825 @deftp {Data type} php-fpm-static-process-manager-configuration
19826 Data Type for the @code{static} php-fpm process manager. With the
19827 @code{static} process manager, an unchanging number of worker processes
19830 @item @code{max-children} (default: @code{5})
19831 Maximum of worker processes.
19835 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
19836 Data Type for the @code{on-demand} php-fpm process manager. With the
19837 @code{on-demand} process manager, worker processes are only created as
19840 @item @code{max-children} (default: @code{5})
19841 Maximum of worker processes.
19842 @item @code{process-idle-timeout} (default: @code{10})
19843 The time in seconds after which a process with no requests is killed.
19848 @deffn {Scheme Procedure} nginx-php-fpm-location @
19849 [#:nginx-package nginx] @
19850 [socket (string-append "/var/run/php" @
19851 (version-major (package-version php)) @
19853 A helper function to quickly add php to an @code{nginx-server-configuration}.
19856 A simple services setup for nginx with php can look like this:
19858 (services (cons* (service dhcp-client-service-type)
19859 (service php-fpm-service-type)
19860 (service nginx-service-type
19861 (nginx-server-configuration
19862 (server-name '("example.com"))
19863 (root "/srv/http/")
19865 (list (nginx-php-location)))
19867 (ssl-certificate #f)
19868 (ssl-certificate-key #f)))
19872 @cindex cat-avatar-generator
19873 The cat avatar generator is a simple service to demonstrate the use of php-fpm
19874 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
19875 the hash of a user's email address.
19877 @deffn {Scheme Procedure} cat-avatar-generator-service @
19878 [#:cache-dir "/var/cache/cat-avatar-generator"] @
19879 [#:package cat-avatar-generator] @
19880 [#:configuration (nginx-server-configuration)]
19881 Returns an nginx-server-configuration that inherits @code{configuration}. It
19882 extends the nginx configuration to add a server block that serves @code{package},
19883 a version of cat-avatar-generator. During execution, cat-avatar-generator will
19884 be able to use @code{cache-dir} as its cache directory.
19887 A simple setup for cat-avatar-generator can look like this:
19889 (services (cons* (cat-avatar-generator-service
19891 (nginx-server-configuration
19892 (server-name '("example.com"))))
19897 @subsubheading Hpcguix-web
19899 @cindex hpcguix-web
19900 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
19901 program is a customizable web interface to browse Guix packages,
19902 initially designed for users of high-performance computing (HPC)
19905 @defvr {Scheme Variable} hpcguix-web-service-type
19906 The service type for @code{hpcguix-web}.
19909 @deftp {Data Type} hpcguix-web-configuration
19910 Data type for the hpcguix-web service configuration.
19914 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
19915 configuration. The main items available in this spec are:
19918 @item @code{title-prefix} (default: @code{"hpcguix | "})
19919 The page title prefix.
19921 @item @code{guix-command} (default: @code{"guix"})
19922 The @command{guix} command.
19924 @item @code{package-filter-proc} (default: @code{(const #t)})
19925 A procedure specifying how to filter packages that are displayed.
19927 @item @code{package-page-extension-proc} (default: @code{(const '())})
19928 Extension package for @code{hpcguix-web}.
19930 @item @code{menu} (default: @code{'()})
19931 Additional entry in page @code{menu}.
19933 @item @code{channels} (default: @code{%default-channels})
19934 List of channels from which the package list is built (@pxref{Channels}).
19936 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
19937 The expiration time, in seconds, after which the package list is rebuilt from
19938 the latest instances of the given channels.
19941 See the hpcguix-web repository for a
19942 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
19945 @item @code{package} (default: @code{hpcguix-web})
19946 The hpcguix-web package to use.
19950 A typical hpcguix-web service declaration looks like this:
19953 (service hpcguix-web-service-type
19954 (hpcguix-web-configuration
19956 #~(define site-config
19957 (hpcweb-configuration
19958 (title-prefix "Guix-HPC - ")
19959 (menu '(("/about" "ABOUT"))))))))
19963 The hpcguix-web service periodically updates the package list it publishes by
19964 pulling channels from Git. To that end, it needs to access X.509 certificates
19965 so that it can authenticate Git servers when communicating over HTTPS, and it
19966 assumes that @file{/etc/ssl/certs} contains those certificates.
19968 Thus, make sure to add @code{nss-certs} or another certificate package to the
19969 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
19970 more information on X.509 certificates.
19973 @node Certificate Services
19974 @subsection Certificate Services
19977 @cindex HTTP, HTTPS
19978 @cindex Let's Encrypt
19979 @cindex TLS certificates
19980 The @code{(gnu services certbot)} module provides a service to
19981 automatically obtain a valid TLS certificate from the Let's Encrypt
19982 certificate authority. These certificates can then be used to serve
19983 content securely over HTTPS or other TLS-based protocols, with the
19984 knowledge that the client will be able to verify the server's
19987 @url{https://letsencrypt.org/, Let's Encrypt} provides the
19988 @code{certbot} tool to automate the certification process. This tool
19989 first securely generates a key on the server. It then makes a request
19990 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
19991 checks that the request originates from the host in question by using a
19992 challenge-response protocol, requiring the server to provide its
19993 response over HTTP. If that protocol completes successfully, the CA
19994 signs the key, resulting in a certificate. That certificate is valid
19995 for a limited period of time, and therefore to continue to provide TLS
19996 services, the server needs to periodically ask the CA to renew its
19999 The certbot service automates this process: the initial key
20000 generation, the initial certification request to the Let's Encrypt
20001 service, the web server challenge/response integration, writing the
20002 certificate to disk, the automated periodic renewals, and the deployment
20003 tasks associated with the renewal (e.g.@: reloading services, copying keys
20004 with different permissions).
20006 Certbot is run twice a day, at a random minute within the hour. It
20007 won't do anything until your certificates are due for renewal or
20008 revoked, but running it regularly would give your service a chance of
20009 staying online in case a Let's Encrypt-initiated revocation happened for
20012 By using this service, you agree to the ACME Subscriber Agreement, which
20013 can be found there:
20014 @url{https://acme-v01.api.letsencrypt.org/directory}.
20016 @defvr {Scheme Variable} certbot-service-type
20017 A service type for the @code{certbot} Let's Encrypt client. Its value
20018 must be a @code{certbot-configuration} record as in this example:
20021 (define %nginx-deploy-hook
20023 "nginx-deploy-hook"
20024 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
20025 (kill pid SIGHUP))))
20027 (service certbot-service-type
20028 (certbot-configuration
20029 (email "foo@@example.net")
20032 (certificate-configuration
20033 (domains '("example.net" "www.example.net"))
20034 (deploy-hook %nginx-deploy-hook))
20035 (certificate-configuration
20036 (domains '("bar.example.net")))))))
20039 See below for details about @code{certbot-configuration}.
20042 @deftp {Data Type} certbot-configuration
20043 Data type representing the configuration of the @code{certbot} service.
20044 This type has the following parameters:
20047 @item @code{package} (default: @code{certbot})
20048 The certbot package to use.
20050 @item @code{webroot} (default: @code{/var/www})
20051 The directory from which to serve the Let's Encrypt challenge/response
20054 @item @code{certificates} (default: @code{()})
20055 A list of @code{certificates-configuration}s for which to generate
20056 certificates and request signatures. Each certificate has a @code{name}
20057 and several @code{domains}.
20060 Mandatory email used for registration, recovery contact, and important
20061 account notifications.
20063 @item @code{rsa-key-size} (default: @code{2048})
20064 Size of the RSA key.
20066 @item @code{default-location} (default: @i{see below})
20067 The default @code{nginx-location-configuration}. Because @code{certbot}
20068 needs to be able to serve challenges and responses, it needs to be able
20069 to run a web server. It does so by extending the @code{nginx} web
20070 service with an @code{nginx-server-configuration} listening on the
20071 @var{domains} on port 80, and which has a
20072 @code{nginx-location-configuration} for the @code{/.well-known/} URI
20073 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
20074 these nginx configuration data types.
20076 Requests to other URL paths will be matched by the
20077 @code{default-location}, which if present is added to all
20078 @code{nginx-server-configuration}s.
20080 By default, the @code{default-location} will issue a redirect from
20081 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
20082 you to define what to serve on your site via @code{https}.
20084 Pass @code{#f} to not issue a default location.
20088 @deftp {Data Type} certificate-configuration
20089 Data type representing the configuration of a certificate.
20090 This type has the following parameters:
20093 @item @code{name} (default: @i{see below})
20094 This name is used by Certbot for housekeeping and in file paths; it
20095 doesn't affect the content of the certificate itself. To see
20096 certificate names, run @code{certbot certificates}.
20098 Its default is the first provided domain.
20100 @item @code{domains} (default: @code{()})
20101 The first domain provided will be the subject CN of the certificate, and
20102 all domains will be Subject Alternative Names on the certificate.
20104 @item @code{challenge} (default: @code{#f})
20105 The challenge type that has to be run by certbot. If @code{#f} is specified,
20106 default to the HTTP challenge. If a value is specified, defaults to the
20107 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
20108 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}).
20110 @item @code{authentication-hook} (default: @code{#f})
20111 Command to be run in a shell once for each certificate challenge to be
20112 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
20113 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
20114 contains the validation string and @code{$CERTBOT_TOKEN} contains the
20115 file name of the resource requested when performing an HTTP-01 challenge.
20117 @item @code{cleanup-hook} (default: @code{#f})
20118 Command to be run in a shell once for each certificate challenge that
20119 have been answered by the @code{auth-hook}. For this command, the shell
20120 variables available in the @code{auth-hook} script are still available, and
20121 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
20122 of the @code{auth-hook} script.
20124 @item @code{deploy-hook} (default: @code{#f})
20125 Command to be run in a shell once for each successfully issued
20126 certificate. For this command, the shell variable
20127 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
20128 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
20129 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
20130 contain a space-delimited list of renewed certificate domains (for
20131 example, @samp{"example.com www.example.com"}.
20136 For each @code{certificate-configuration}, the certificate is saved to
20137 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
20138 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
20140 @subsection DNS Services
20141 @cindex DNS (domain name system)
20142 @cindex domain name system (DNS)
20144 The @code{(gnu services dns)} module provides services related to the
20145 @dfn{domain name system} (DNS). It provides a server service for hosting
20146 an @emph{authoritative} DNS server for multiple zones, slave or master.
20147 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
20148 caching and forwarding DNS server for the LAN, which uses
20149 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
20151 @subsubheading Knot Service
20153 An example configuration of an authoritative server for two zones, one master
20157 (define-zone-entries example.org.zone
20158 ;; Name TTL Class Type Data
20159 ("@@" "" "IN" "A" "127.0.0.1")
20160 ("@@" "" "IN" "NS" "ns")
20161 ("ns" "" "IN" "A" "127.0.0.1"))
20163 (define master-zone
20164 (knot-zone-configuration
20165 (domain "example.org")
20167 (origin "example.org")
20168 (entries example.org.zone)))))
20171 (knot-zone-configuration
20172 (domain "plop.org")
20173 (dnssec-policy "default")
20174 (master (list "plop-master"))))
20176 (define plop-master
20177 (knot-remote-configuration
20179 (address (list "208.76.58.171"))))
20183 (services (cons* (service knot-service-type
20184 (knot-configuration
20185 (remotes (list plop-master))
20186 (zones (list master-zone slave-zone))))
20191 @deffn {Scheme Variable} knot-service-type
20192 This is the type for the Knot DNS server.
20194 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
20195 zones, that is to say domain names you would buy from a registrar. This server
20196 is not a resolver, meaning that it can only resolve names for which it is
20197 authoritative. This server can be configured to serve zones as a master server
20198 or a slave server as a per-zone basis. Slave zones will get their data from
20199 masters, and will serve it as an authoritative server. From the point of view
20200 of a resolver, there is no difference between master and slave.
20202 The following data types are used to configure the Knot DNS server:
20205 @deftp {Data Type} knot-key-configuration
20206 Data type representing a key.
20207 This type has the following parameters:
20210 @item @code{id} (default: @code{""})
20211 An identifier for other configuration fields to refer to this key. IDs must
20212 be unique and must not be empty.
20214 @item @code{algorithm} (default: @code{#f})
20215 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
20216 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
20217 and @code{'hmac-sha512}.
20219 @item @code{secret} (default: @code{""})
20220 The secret key itself.
20225 @deftp {Data Type} knot-acl-configuration
20226 Data type representing an Access Control List (ACL) configuration.
20227 This type has the following parameters:
20230 @item @code{id} (default: @code{""})
20231 An identifier for ether configuration fields to refer to this key. IDs must be
20232 unique and must not be empty.
20234 @item @code{address} (default: @code{'()})
20235 An ordered list of IP addresses, network subnets, or network ranges represented
20236 with strings. The query must match one of them. Empty value means that
20237 address match is not required.
20239 @item @code{key} (default: @code{'()})
20240 An ordered list of references to keys represented with strings. The string
20241 must match a key ID defined in a @code{knot-key-configuration}. No key means
20242 that a key is not require to match that ACL.
20244 @item @code{action} (default: @code{'()})
20245 An ordered list of actions that are permitted or forbidden by this ACL. Possible
20246 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
20247 and @code{'update}.
20249 @item @code{deny?} (default: @code{#f})
20250 When true, the ACL defines restrictions. Listed actions are forbidden. When
20251 false, listed actions are allowed.
20256 @deftp {Data Type} zone-entry
20257 Data type represnting a record entry in a zone file.
20258 This type has the following parameters:
20261 @item @code{name} (default: @code{"@@"})
20262 The name of the record. @code{"@@"} refers to the origin of the zone. Names
20263 are relative to the origin of the zone. For example, in the @code{example.org}
20264 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
20265 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
20266 refers to @code{ns.example.org}.
20268 @item @code{ttl} (default: @code{""})
20269 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
20271 @item @code{class} (default: @code{"IN"})
20272 The class of the record. Knot currently supports only @code{"IN"} and
20273 partially @code{"CH"}.
20275 @item @code{type} (default: @code{"A"})
20276 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
20277 address), NS (Name Server) and MX (Mail eXchange). Many other types are
20280 @item @code{data} (default: @code{""})
20281 The data contained in the record. For instance an IP address associated with
20282 an A record, or a domain name associated with an NS record. Remember that
20283 domain names are relative to the origin unless they end with a dot.
20288 @deftp {Data Type} zone-file
20289 Data type representing the content of a zone file.
20290 This type has the following parameters:
20293 @item @code{entries} (default: @code{'()})
20294 The list of entries. The SOA record is taken care of, so you don't need to
20295 put it in the list of entries. This list should probably contain an entry
20296 for your primary authoritative DNS server. Other than using a list of entries
20297 directly, you can use @code{define-zone-entries} to define a object containing
20298 the list of entries more easily, that you can later pass to the @code{entries}
20299 field of the @code{zone-file}.
20301 @item @code{origin} (default: @code{""})
20302 The name of your zone. This parameter cannot be empty.
20304 @item @code{ns} (default: @code{"ns"})
20305 The domain of your primary authoritative DNS server. The name is relative to
20306 the origin, unless it ends with a dot. It is mandatory that this primary
20307 DNS server corresponds to an NS record in the zone and that it is associated
20308 to an IP address in the list of entries.
20310 @item @code{mail} (default: @code{"hostmaster"})
20311 An email address people can contact you at, as the owner of the zone. This
20312 is translated as @code{<mail>@@<origin>}.
20314 @item @code{serial} (default: @code{1})
20315 The serial number of the zone. As this is used to keep track of changes by
20316 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
20317 Always increment it when you make a change in your zone.
20319 @item @code{refresh} (default: @code{(* 2 24 3600)})
20320 The frequency at which slaves will do a zone transfer. This value is a number
20321 of seconds. It can be computed by multiplications or with
20322 @code{(string->duration)}.
20324 @item @code{retry} (default: @code{(* 15 60)})
20325 The period after which a slave will retry to contact its master when it fails
20326 to do so a first time.
20328 @item @code{expiry} (default: @code{(* 14 24 3600)})
20329 Default TTL of records. Existing records are considered correct for at most
20330 this amount of time. After this period, resolvers will invalidate their cache
20331 and check again that it still exists.
20333 @item @code{nx} (default: @code{3600})
20334 Default TTL of inexistant records. This delay is usually short because you want
20335 your new domains to reach everyone quickly.
20340 @deftp {Data Type} knot-remote-configuration
20341 Data type representing a remote configuration.
20342 This type has the following parameters:
20345 @item @code{id} (default: @code{""})
20346 An identifier for other configuration fields to refer to this remote. IDs must
20347 be unique and must not be empty.
20349 @item @code{address} (default: @code{'()})
20350 An ordered list of destination IP addresses. Addresses are tried in sequence.
20351 An optional port can be given with the @@ separator. For instance:
20352 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
20354 @item @code{via} (default: @code{'()})
20355 An ordered list of source IP addresses. An empty list will have Knot choose
20356 an appropriate source IP. An optional port can be given with the @@ separator.
20357 The default is to choose at random.
20359 @item @code{key} (default: @code{#f})
20360 A reference to a key, that is a string containing the identifier of a key
20361 defined in a @code{knot-key-configuration} field.
20366 @deftp {Data Type} knot-keystore-configuration
20367 Data type representing a keystore to hold dnssec keys.
20368 This type has the following parameters:
20371 @item @code{id} (default: @code{""})
20372 The id of the keystore. It must not be empty.
20374 @item @code{backend} (default: @code{'pem})
20375 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
20377 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
20378 The configuration string of the backend. An example for the PKCS#11 is:
20379 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
20380 For the pem backend, the string reprensents a path in the file system.
20385 @deftp {Data Type} knot-policy-configuration
20386 Data type representing a dnssec policy. Knot DNS is able to automatically
20387 sign your zones. It can either generate and manage your keys automatically or
20388 use keys that you generate.
20390 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
20391 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
20392 zone. In order to be trusted, the KSK needs to be present in the parent zone
20393 (usually a top-level domain). If your registrar supports dnssec, you will
20394 have to send them your KSK's hash so they can add a DS record in their zone.
20395 This is not automated and need to be done each time you change your KSK.
20397 The policy also defines the lifetime of keys. Usually, ZSK can be changed
20398 easily and use weaker cryptographic functions (they use lower parameters) in
20399 order to sign records quickly, so they are changed often. The KSK however
20400 requires manual interaction with the registrar, so they are changed less often
20401 and use stronger parameters because they sign only one record.
20403 This type has the following parameters:
20406 @item @code{id} (default: @code{""})
20407 The id of the policy. It must not be empty.
20409 @item @code{keystore} (default: @code{"default"})
20410 A reference to a keystore, that is a string containing the identifier of a
20411 keystore defined in a @code{knot-keystore-configuration} field. The
20412 @code{"default"} identifier means the default keystore (a kasp database that
20413 was setup by this service).
20415 @item @code{manual?} (default: @code{#f})
20416 Whether the key management is manual or automatic.
20418 @item @code{single-type-signing?} (default: @code{#f})
20419 When @code{#t}, use the Single-Type Signing Scheme.
20421 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
20422 An algorithm of signing keys and issued signatures.
20424 @item @code{ksk-size} (default: @code{256})
20425 The length of the KSK. Note that this value is correct for the default
20426 algorithm, but would be unsecure for other algorithms.
20428 @item @code{zsk-size} (default: @code{256})
20429 The length of the ZSK. Note that this value is correct for the default
20430 algorithm, but would be unsecure for other algorithms.
20432 @item @code{dnskey-ttl} (default: @code{'default})
20433 The TTL value for DNSKEY records added into zone apex. The special
20434 @code{'default} value means same as the zone SOA TTL.
20436 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
20437 The period between ZSK publication and the next rollover initiation.
20439 @item @code{propagation-delay} (default: @code{(* 24 3600)})
20440 An extra delay added for each key rollover step. This value should be high
20441 enough to cover propagation of data from the master server to all slaves.
20443 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
20444 A validity period of newly issued signatures.
20446 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
20447 A period how long before a signature expiration the signature will be refreshed.
20449 @item @code{nsec3?} (default: @code{#f})
20450 When @code{#t}, NSEC3 will be used instead of NSEC.
20452 @item @code{nsec3-iterations} (default: @code{5})
20453 The number of additional times the hashing is performed.
20455 @item @code{nsec3-salt-length} (default: @code{8})
20456 The length of a salt field in octets, which is appended to the original owner
20457 name before hashing.
20459 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
20460 The validity period of newly issued salt field.
20465 @deftp {Data Type} knot-zone-configuration
20466 Data type representing a zone served by Knot.
20467 This type has the following parameters:
20470 @item @code{domain} (default: @code{""})
20471 The domain served by this configuration. It must not be empty.
20473 @item @code{file} (default: @code{""})
20474 The file where this zone is saved. This parameter is ignored by master zones.
20475 Empty means default location that depends on the domain name.
20477 @item @code{zone} (default: @code{(zone-file)})
20478 The content of the zone file. This parameter is ignored by slave zones. It
20479 must contain a zone-file record.
20481 @item @code{master} (default: @code{'()})
20482 A list of master remotes. When empty, this zone is a master. When set, this
20483 zone is a slave. This is a list of remotes identifiers.
20485 @item @code{ddns-master} (default: @code{#f})
20486 The main master. When empty, it defaults to the first master in the list of
20489 @item @code{notify} (default: @code{'()})
20490 A list of slave remote identifiers.
20492 @item @code{acl} (default: @code{'()})
20493 A list of acl identifiers.
20495 @item @code{semantic-checks?} (default: @code{#f})
20496 When set, this adds more semantic checks to the zone.
20498 @item @code{disable-any?} (default: @code{#f})
20499 When set, this forbids queries of the ANY type.
20501 @item @code{zonefile-sync} (default: @code{0})
20502 The delay between a modification in memory and on disk. 0 means immediate
20505 @item @code{zonefile-load} (default: @code{#f})
20506 The way the zone file contents are applied during zone load. Possible values
20510 @item @code{#f} for using the default value from Knot,
20511 @item @code{'none} for not using the zone file at all,
20512 @item @code{'difference} for computing the difference between already available
20513 contents and zone contents and applying it to the current zone contents,
20514 @item @code{'difference-no-serial} for the same as @code{'difference}, but
20515 ignoring the SOA serial in the zone file, while the server takes care of it
20517 @item @code{'whole} for loading zone contents from the zone file.
20520 @item @code{journal-content} (default: @code{#f})
20521 The way the journal is used to store zone and its changes. Possible values
20522 are @code{'none} to not use it at all, @code{'changes} to store changes and
20523 @code{'all} to store contents. @code{#f} does not set this option, so the
20524 default value from Knot is used.
20526 @item @code{max-journal-usage} (default: @code{#f})
20527 The maximum size for the journal on disk. @code{#f} does not set this option,
20528 so the default value from Knot is used.
20530 @item @code{max-journal-depth} (default: @code{#f})
20531 The maximum size of the history. @code{#f} does not set this option, so the
20532 default value from Knot is used.
20534 @item @code{max-zone-size} (default: @code{#f})
20535 The maximum size of the zone file. This limit is enforced for incoming
20536 transfer and updates. @code{#f} does not set this option, so the default
20537 value from Knot is used.
20539 @item @code{dnssec-policy} (default: @code{#f})
20540 A reference to a @code{knot-policy-configuration} record, or the special
20541 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
20544 @item @code{serial-policy} (default: @code{'increment})
20545 A policy between @code{'increment} and @code{'unixtime}.
20550 @deftp {Data Type} knot-configuration
20551 Data type representing the Knot configuration.
20552 This type has the following parameters:
20555 @item @code{knot} (default: @code{knot})
20558 @item @code{run-directory} (default: @code{"/var/run/knot"})
20559 The run directory. This directory will be used for pid file and sockets.
20561 @item @code{includes} (default: @code{'()})
20562 A list of strings or file-like objects denoting other files that must be
20563 included at the top of the configuration file.
20565 @cindex secrets, Knot service
20566 This can be used to manage secrets out-of-band. For example, secret
20567 keys may be stored in an out-of-band file not managed by Guix, and
20568 thus not visible in @file{/gnu/store}---e.g., you could store secret
20569 key configuration in @file{/etc/knot/secrets.conf} and add this file
20570 to the @code{includes} list.
20572 It can also be used to add configuration not supported by this interface.
20574 @item @code{listen-v4} (default: @code{"0.0.0.0"})
20575 An ip address on which to listen.
20577 @item @code{listen-v6} (default: @code{"::"})
20578 An ip address on which to listen.
20580 @item @code{listen-port} (default: @code{53})
20581 A port on which to listen.
20583 @item @code{keys} (default: @code{'()})
20584 The list of knot-key-configuration used by this configuration.
20586 @item @code{acls} (default: @code{'()})
20587 The list of knot-acl-configuration used by this configuration.
20589 @item @code{remotes} (default: @code{'()})
20590 The list of knot-remote-configuration used by this configuration.
20592 @item @code{zones} (default: @code{'()})
20593 The list of knot-zone-configuration used by this configuration.
20598 @subsubheading Dnsmasq Service
20600 @deffn {Scheme Variable} dnsmasq-service-type
20601 This is the type of the dnsmasq service, whose value should be an
20602 @code{dnsmasq-configuration} object as in this example:
20605 (service dnsmasq-service-type
20606 (dnsmasq-configuration
20608 (servers '("192.168.1.1"))))
20612 @deftp {Data Type} dnsmasq-configuration
20613 Data type representing the configuration of dnsmasq.
20616 @item @code{package} (default: @var{dnsmasq})
20617 Package object of the dnsmasq server.
20619 @item @code{no-hosts?} (default: @code{#f})
20620 When true, don't read the hostnames in /etc/hosts.
20622 @item @code{port} (default: @code{53})
20623 The port to listen on. Setting this to zero completely disables DNS
20624 responses, leaving only DHCP and/or TFTP functions.
20626 @item @code{local-service?} (default: @code{#t})
20627 Accept DNS queries only from hosts whose address is on a local subnet,
20628 ie a subnet for which an interface exists on the server.
20630 @item @code{listen-addresses} (default: @code{'()})
20631 Listen on the given IP addresses.
20633 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
20634 The file to read the IP address of the upstream nameservers from.
20636 @item @code{no-resolv?} (default: @code{#f})
20637 When true, don't read @var{resolv-file}.
20639 @item @code{servers} (default: @code{'()})
20640 Specify IP address of upstream servers directly.
20642 @item @code{cache-size} (default: @code{150})
20643 Set the size of dnsmasq's cache. Setting the cache size to zero
20646 @item @code{negative-cache?} (default: @code{#t})
20647 When false, disable negative caching.
20652 @subsubheading ddclient Service
20655 The ddclient service described below runs the ddclient daemon, which takes
20656 care of automatically updating DNS entries for service providers such as
20657 @uref{https://dyn.com/dns/, Dyn}.
20659 The following example show instantiates the service with its default
20663 (service ddclient-service-type)
20666 Note that ddclient needs to access credentials that are stored in a
20667 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
20668 @code{secret-file} below.) You are expected to create this file manually, in
20669 an ``out-of-band'' fashion (you @emph{could} make this file part of the
20670 service configuration, for instance by using @code{plain-file}, but it will be
20671 world-readable @i{via} @file{/gnu/store}.) See the examples in the
20672 @file{share/ddclient} directory of the @code{ddclient} package.
20674 @c %start of fragment
20676 Available @code{ddclient-configuration} fields are:
20678 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
20679 The ddclient package.
20683 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
20684 The period after which ddclient will retry to check IP and domain name.
20686 Defaults to @samp{300}.
20690 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
20691 Use syslog for the output.
20693 Defaults to @samp{#t}.
20697 @deftypevr {@code{ddclient-configuration} parameter} string mail
20700 Defaults to @samp{"root"}.
20704 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
20705 Mail failed update to user.
20707 Defaults to @samp{"root"}.
20711 @deftypevr {@code{ddclient-configuration} parameter} string pid
20712 The ddclient PID file.
20714 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
20718 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
20719 Enable SSL support.
20721 Defaults to @samp{#t}.
20725 @deftypevr {@code{ddclient-configuration} parameter} string user
20726 Specifies the user name or ID that is used when running ddclient
20729 Defaults to @samp{"ddclient"}.
20733 @deftypevr {@code{ddclient-configuration} parameter} string group
20734 Group of the user who will run the ddclient program.
20736 Defaults to @samp{"ddclient"}.
20740 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
20741 Secret file which will be appended to @file{ddclient.conf} file. This
20742 file contains credentials for use by ddclient. You are expected to
20743 create it manually.
20745 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
20749 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
20750 Extra options will be appended to @file{ddclient.conf} file.
20752 Defaults to @samp{()}.
20757 @c %end of fragment
20761 @subsection VPN Services
20762 @cindex VPN (virtual private network)
20763 @cindex virtual private network (VPN)
20765 The @code{(gnu services vpn)} module provides services related to
20766 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
20767 your machine to connect to a VPN, and a @emph{server} service for your machine
20768 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
20770 @deffn {Scheme Procedure} openvpn-client-service @
20771 [#:config (openvpn-client-configuration)]
20773 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
20776 @deffn {Scheme Procedure} openvpn-server-service @
20777 [#:config (openvpn-server-configuration)]
20779 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
20781 Both can be run simultaneously.
20784 @c %automatically generated documentation
20786 Available @code{openvpn-client-configuration} fields are:
20788 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
20789 The OpenVPN package.
20793 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
20794 The OpenVPN pid file.
20796 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
20800 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
20801 The protocol (UDP or TCP) used to open a channel between clients and
20804 Defaults to @samp{udp}.
20808 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
20809 The device type used to represent the VPN connection.
20811 Defaults to @samp{tun}.
20815 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
20816 The certificate authority to check connections against.
20818 Defaults to @samp{"/etc/openvpn/ca.crt"}.
20822 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
20823 The certificate of the machine the daemon is running on. It should be
20824 signed by the authority given in @code{ca}.
20826 Defaults to @samp{"/etc/openvpn/client.crt"}.
20830 @deftypevr {@code{openvpn-client-configuration} parameter} string key
20831 The key of the machine the daemon is running on. It must be the key whose
20832 certificate is @code{cert}.
20834 Defaults to @samp{"/etc/openvpn/client.key"}.
20838 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
20839 Whether to use the lzo compression algorithm.
20841 Defaults to @samp{#t}.
20845 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
20846 Don't re-read key files across SIGUSR1 or --ping-restart.
20848 Defaults to @samp{#t}.
20852 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
20853 Don't close and reopen TUN/TAP device or run up/down scripts across
20854 SIGUSR1 or --ping-restart restarts.
20856 Defaults to @samp{#t}.
20860 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
20863 Defaults to @samp{3}.
20867 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
20868 Add an additional layer of HMAC authentication on top of the TLS control
20869 channel to protect against DoS attacks.
20871 Defaults to @samp{#f}.
20875 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
20876 Whether to check the server certificate has server usage extension.
20878 Defaults to @samp{#t}.
20882 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
20883 Bind to a specific local port number.
20885 Defaults to @samp{#f}.
20889 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
20890 Retry resolving server address.
20892 Defaults to @samp{#t}.
20896 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
20897 A list of remote servers to connect to.
20899 Defaults to @samp{()}.
20901 Available @code{openvpn-remote-configuration} fields are:
20903 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
20906 Defaults to @samp{"my-server"}.
20910 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
20911 Port number the server listens to.
20913 Defaults to @samp{1194}.
20918 @c %end of automatic openvpn-client documentation
20920 @c %automatically generated documentation
20922 Available @code{openvpn-server-configuration} fields are:
20924 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
20925 The OpenVPN package.
20929 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
20930 The OpenVPN pid file.
20932 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
20936 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
20937 The protocol (UDP or TCP) used to open a channel between clients and
20940 Defaults to @samp{udp}.
20944 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
20945 The device type used to represent the VPN connection.
20947 Defaults to @samp{tun}.
20951 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
20952 The certificate authority to check connections against.
20954 Defaults to @samp{"/etc/openvpn/ca.crt"}.
20958 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
20959 The certificate of the machine the daemon is running on. It should be
20960 signed by the authority given in @code{ca}.
20962 Defaults to @samp{"/etc/openvpn/client.crt"}.
20966 @deftypevr {@code{openvpn-server-configuration} parameter} string key
20967 The key of the machine the daemon is running on. It must be the key whose
20968 certificate is @code{cert}.
20970 Defaults to @samp{"/etc/openvpn/client.key"}.
20974 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
20975 Whether to use the lzo compression algorithm.
20977 Defaults to @samp{#t}.
20981 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
20982 Don't re-read key files across SIGUSR1 or --ping-restart.
20984 Defaults to @samp{#t}.
20988 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
20989 Don't close and reopen TUN/TAP device or run up/down scripts across
20990 SIGUSR1 or --ping-restart restarts.
20992 Defaults to @samp{#t}.
20996 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
20999 Defaults to @samp{3}.
21003 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
21004 Add an additional layer of HMAC authentication on top of the TLS control
21005 channel to protect against DoS attacks.
21007 Defaults to @samp{#f}.
21011 @deftypevr {@code{openvpn-server-configuration} parameter} number port
21012 Specifies the port number on which the server listens.
21014 Defaults to @samp{1194}.
21018 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
21019 An ip and mask specifying the subnet inside the virtual network.
21021 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
21025 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
21026 A CIDR notation specifying the IPv6 subnet inside the virtual network.
21028 Defaults to @samp{#f}.
21032 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
21033 The Diffie-Hellman parameters file.
21035 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
21039 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
21040 The file that records client IPs.
21042 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
21046 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
21047 When true, the server will act as a gateway for its clients.
21049 Defaults to @samp{#f}.
21053 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
21054 When true, clients are allowed to talk to each other inside the VPN.
21056 Defaults to @samp{#f}.
21060 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
21061 Causes ping-like messages to be sent back and forth over the link so
21062 that each side knows when the other side has gone down. @code{keepalive}
21063 requires a pair. The first element is the period of the ping sending,
21064 and the second element is the timeout before considering the other side
21069 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
21070 The maximum number of clients.
21072 Defaults to @samp{100}.
21076 @deftypevr {@code{openvpn-server-configuration} parameter} string status
21077 The status file. This file shows a small report on current connection.
21078 It is truncated and rewritten every minute.
21080 Defaults to @samp{"/var/run/openvpn/status"}.
21084 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
21085 The list of configuration for some clients.
21087 Defaults to @samp{()}.
21089 Available @code{openvpn-ccd-configuration} fields are:
21091 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
21094 Defaults to @samp{"client"}.
21098 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
21101 Defaults to @samp{#f}.
21105 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
21108 Defaults to @samp{#f}.
21115 @c %end of automatic openvpn-server documentation
21118 @node Network File System
21119 @subsection Network File System
21122 The @code{(gnu services nfs)} module provides the following services,
21123 which are most commonly used in relation to mounting or exporting
21124 directory trees as @dfn{network file systems} (NFS).
21126 @subsubheading RPC Bind Service
21129 The RPC Bind service provides a facility to map program numbers into
21130 universal addresses.
21131 Many NFS related services use this facility. Hence it is automatically
21132 started when a dependent service starts.
21134 @defvr {Scheme Variable} rpcbind-service-type
21135 A service type for the RPC portmapper daemon.
21139 @deftp {Data Type} rpcbind-configuration
21140 Data type representing the configuration of the RPC Bind Service.
21141 This type has the following parameters:
21143 @item @code{rpcbind} (default: @code{rpcbind})
21144 The rpcbind package to use.
21146 @item @code{warm-start?} (default: @code{#t})
21147 If this parameter is @code{#t}, then the daemon will read a
21148 state file on startup thus reloading state information saved by a previous
21154 @subsubheading Pipefs Pseudo File System
21158 The pipefs file system is used to transfer NFS related data
21159 between the kernel and user space programs.
21161 @defvr {Scheme Variable} pipefs-service-type
21162 A service type for the pipefs pseudo file system.
21165 @deftp {Data Type} pipefs-configuration
21166 Data type representing the configuration of the pipefs pseudo file system service.
21167 This type has the following parameters:
21169 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21170 The directory to which the file system is to be attached.
21175 @subsubheading GSS Daemon Service
21178 @cindex global security system
21180 The @dfn{global security system} (GSS) daemon provides strong security for RPC
21182 Before exchanging RPC requests an RPC client must establish a security
21183 context. Typically this is done using the Kerberos command @command{kinit}
21184 or automatically at login time using PAM services (@pxref{Kerberos Services}).
21186 @defvr {Scheme Variable} gss-service-type
21187 A service type for the Global Security System (GSS) daemon.
21190 @deftp {Data Type} gss-configuration
21191 Data type representing the configuration of the GSS daemon service.
21192 This type has the following parameters:
21194 @item @code{nfs-utils} (default: @code{nfs-utils})
21195 The package in which the @command{rpc.gssd} command is to be found.
21197 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21198 The directory where the pipefs file system is mounted.
21204 @subsubheading IDMAP Daemon Service
21206 @cindex name mapper
21208 The idmap daemon service provides mapping between user IDs and user names.
21209 Typically it is required in order to access file systems mounted via NFSv4.
21211 @defvr {Scheme Variable} idmap-service-type
21212 A service type for the Identity Mapper (IDMAP) daemon.
21215 @deftp {Data Type} idmap-configuration
21216 Data type representing the configuration of the IDMAP daemon service.
21217 This type has the following parameters:
21219 @item @code{nfs-utils} (default: @code{nfs-utils})
21220 The package in which the @command{rpc.idmapd} command is to be found.
21222 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
21223 The directory where the pipefs file system is mounted.
21225 @item @code{domain} (default: @code{#f})
21226 The local NFSv4 domain name.
21227 This must be a string or @code{#f}.
21228 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
21233 @node Continuous Integration
21234 @subsection Continuous Integration
21236 @cindex continuous integration
21237 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
21238 continuous integration tool for Guix. It can be used both for development and
21239 for providing substitutes to others (@pxref{Substitutes}).
21241 The @code{(gnu services cuirass)} module provides the following service.
21243 @defvr {Scheme Procedure} cuirass-service-type
21244 The type of the Cuirass service. Its value must be a
21245 @code{cuirass-configuration} object, as described below.
21248 To add build jobs, you have to set the @code{specifications} field of the
21249 configuration. Here is an example of a service that polls the Guix repository
21250 and builds the packages from a manifest. Some of the packages are defined in
21251 the @code{"custom-packages"} input, which is the equivalent of
21252 @code{GUIX_PACKAGE_PATH}.
21255 (define %cuirass-specs
21257 '((#:name . "my-manifest")
21258 (#:load-path-inputs . ("guix"))
21259 (#:package-path-inputs . ("custom-packages"))
21260 (#:proc-input . "guix")
21261 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
21262 (#:proc . cuirass-jobs)
21263 (#:proc-args . ((subset . "manifests")
21264 (systems . ("x86_64-linux"))
21265 (manifests . (("config" . "guix/manifest.scm")))))
21266 (#:inputs . (((#:name . "guix")
21267 (#:url . "git://git.savannah.gnu.org/guix.git")
21268 (#:load-path . ".")
21269 (#:branch . "master")
21270 (#:no-compile? . #t))
21271 ((#:name . "config")
21272 (#:url . "git://git.example.org/config.git")
21273 (#:load-path . ".")
21274 (#:branch . "master")
21275 (#:no-compile? . #t))
21276 ((#:name . "custom-packages")
21277 (#:url . "git://git.example.org/custom-packages.git")
21278 (#:load-path . ".")
21279 (#:branch . "master")
21280 (#:no-compile? . #t)))))))
21282 (service cuirass-service-type
21283 (cuirass-configuration
21284 (specifications %cuirass-specs)))
21287 While information related to build jobs is located directly in the
21288 specifications, global settings for the @command{cuirass} process are
21289 accessible in other @code{cuirass-configuration} fields.
21291 @deftp {Data Type} cuirass-configuration
21292 Data type representing the configuration of Cuirass.
21295 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
21296 Location of the log file.
21298 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
21299 Location of the repository cache.
21301 @item @code{user} (default: @code{"cuirass"})
21302 Owner of the @code{cuirass} process.
21304 @item @code{group} (default: @code{"cuirass"})
21305 Owner's group of the @code{cuirass} process.
21307 @item @code{interval} (default: @code{60})
21308 Number of seconds between the poll of the repositories followed by the
21311 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
21312 Location of sqlite database which contains the build results and previously
21313 added specifications.
21315 @item @code{ttl} (default: @code{(* 30 24 3600)})
21316 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
21317 are registered for build results. This means that build results are protected
21318 from garbage collection for at least @var{ttl} seconds.
21320 @item @code{port} (default: @code{8081})
21321 Port number used by the HTTP server.
21323 @item --listen=@var{host}
21324 Listen on the network interface for @var{host}. The default is to
21325 accept connections from localhost.
21327 @item @code{specifications} (default: @code{#~'()})
21328 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
21329 where a specification is an association list
21330 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
21331 keys are keywords (@code{#:keyword-example}) as shown in the example
21334 @item @code{use-substitutes?} (default: @code{#f})
21335 This allows using substitutes to avoid building every dependencies of a job
21338 @item @code{one-shot?} (default: @code{#f})
21339 Only evaluate specifications and build derivations once.
21341 @item @code{fallback?} (default: @code{#f})
21342 When substituting a pre-built binary fails, fall back to building
21345 @item @code{cuirass} (default: @code{cuirass})
21346 The Cuirass package to use.
21350 @node Power Management Services
21351 @subsection Power Management Services
21354 @cindex power management with TLP
21355 @subsubheading TLP daemon
21357 The @code{(gnu services pm)} module provides a Guix service definition
21358 for the Linux power management tool TLP.
21360 TLP enables various powersaving modes in userspace and kernel.
21361 Contrary to @code{upower-service}, it is not a passive,
21362 monitoring tool, as it will apply custom settings each time a new power
21363 source is detected. More information can be found at
21364 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
21366 @deffn {Scheme Variable} tlp-service-type
21367 The service type for the TLP tool. Its value should be a valid
21368 TLP configuration (see below). To use the default settings, simply
21371 (service tlp-service-type)
21375 By default TLP does not need much configuration but most TLP parameters
21376 can be tweaked using @code{tlp-configuration}.
21378 Each parameter definition is preceded by its type; for example,
21379 @samp{boolean foo} indicates that the @code{foo} parameter
21380 should be specified as a boolean. Types starting with
21381 @code{maybe-} denote parameters that won't show up in TLP config file
21382 when their value is @code{'disabled}.
21384 @c The following documentation was initially generated by
21385 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
21386 @c documentation is better, so we shouldn't hesitate to edit below as
21387 @c needed. However if the change you want to make to this documentation
21388 @c can be done in an automated way, it's probably easier to change
21389 @c (generate-documentation) than to make it below and have to deal with
21390 @c the churn as TLP updates.
21392 Available @code{tlp-configuration} fields are:
21394 @deftypevr {@code{tlp-configuration} parameter} package tlp
21399 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
21400 Set to true if you wish to enable TLP.
21402 Defaults to @samp{#t}.
21406 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
21407 Default mode when no power supply can be detected. Alternatives are AC
21410 Defaults to @samp{"AC"}.
21414 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
21415 Number of seconds Linux kernel has to wait after the disk goes idle,
21416 before syncing on AC.
21418 Defaults to @samp{0}.
21422 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
21423 Same as @code{disk-idle-ac} but on BAT mode.
21425 Defaults to @samp{2}.
21429 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
21430 Dirty pages flushing periodicity, expressed in seconds.
21432 Defaults to @samp{15}.
21436 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
21437 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
21439 Defaults to @samp{60}.
21443 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
21444 CPU frequency scaling governor on AC mode. With intel_pstate driver,
21445 alternatives are powersave and performance. With acpi-cpufreq driver,
21446 alternatives are ondemand, powersave, performance and conservative.
21448 Defaults to @samp{disabled}.
21452 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
21453 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
21455 Defaults to @samp{disabled}.
21459 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
21460 Set the min available frequency for the scaling governor on AC.
21462 Defaults to @samp{disabled}.
21466 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
21467 Set the max available frequency for the scaling governor on AC.
21469 Defaults to @samp{disabled}.
21473 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
21474 Set the min available frequency for the scaling governor on BAT.
21476 Defaults to @samp{disabled}.
21480 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
21481 Set the max available frequency for the scaling governor on BAT.
21483 Defaults to @samp{disabled}.
21487 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
21488 Limit the min P-state to control the power dissipation of the CPU, in AC
21489 mode. Values are stated as a percentage of the available performance.
21491 Defaults to @samp{disabled}.
21495 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
21496 Limit the max P-state to control the power dissipation of the CPU, in AC
21497 mode. Values are stated as a percentage of the available performance.
21499 Defaults to @samp{disabled}.
21503 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
21504 Same as @code{cpu-min-perf-on-ac} on BAT mode.
21506 Defaults to @samp{disabled}.
21510 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
21511 Same as @code{cpu-max-perf-on-ac} on BAT mode.
21513 Defaults to @samp{disabled}.
21517 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
21518 Enable CPU turbo boost feature on AC mode.
21520 Defaults to @samp{disabled}.
21524 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
21525 Same as @code{cpu-boost-on-ac?} on BAT mode.
21527 Defaults to @samp{disabled}.
21531 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
21532 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
21533 used under light load conditions.
21535 Defaults to @samp{#f}.
21539 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
21540 Same as @code{sched-powersave-on-ac?} but on BAT mode.
21542 Defaults to @samp{#t}.
21546 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
21547 Enable Linux kernel NMI watchdog.
21549 Defaults to @samp{#f}.
21553 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
21554 For Linux kernels with PHC patch applied, change CPU voltages. An
21555 example value would be @samp{"F:V F:V F:V F:V"}.
21557 Defaults to @samp{disabled}.
21561 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
21562 Set CPU performance versus energy saving policy on AC. Alternatives are
21563 performance, normal, powersave.
21565 Defaults to @samp{"performance"}.
21569 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
21570 Same as @code{energy-perf-policy-ac} but on BAT mode.
21572 Defaults to @samp{"powersave"}.
21576 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
21581 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
21582 Hard disk advanced power management level.
21586 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
21587 Same as @code{disk-apm-bat} but on BAT mode.
21591 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
21592 Hard disk spin down timeout. One value has to be specified for each
21593 declared hard disk.
21595 Defaults to @samp{disabled}.
21599 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
21600 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
21602 Defaults to @samp{disabled}.
21606 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
21607 Select IO scheduler for disk devices. One value has to be specified for
21608 each declared hard disk. Example alternatives are cfq, deadline and
21611 Defaults to @samp{disabled}.
21615 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
21616 SATA aggressive link power management (ALPM) level. Alternatives are
21617 min_power, medium_power, max_performance.
21619 Defaults to @samp{"max_performance"}.
21623 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
21624 Same as @code{sata-linkpwr-ac} but on BAT mode.
21626 Defaults to @samp{"min_power"}.
21630 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
21631 Exclude specified SATA host devices for link power management.
21633 Defaults to @samp{disabled}.
21637 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
21638 Enable Runtime Power Management for AHCI controller and disks on AC
21641 Defaults to @samp{disabled}.
21645 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
21646 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
21648 Defaults to @samp{disabled}.
21652 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
21653 Seconds of inactivity before disk is suspended.
21655 Defaults to @samp{15}.
21659 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
21660 PCI Express Active State Power Management level. Alternatives are
21661 default, performance, powersave.
21663 Defaults to @samp{"performance"}.
21667 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
21668 Same as @code{pcie-aspm-ac} but on BAT mode.
21670 Defaults to @samp{"powersave"}.
21674 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
21675 Radeon graphics clock speed level. Alternatives are low, mid, high,
21678 Defaults to @samp{"high"}.
21682 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
21683 Same as @code{radeon-power-ac} but on BAT mode.
21685 Defaults to @samp{"low"}.
21689 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
21690 Radeon dynamic power management method (DPM). Alternatives are battery,
21693 Defaults to @samp{"performance"}.
21697 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
21698 Same as @code{radeon-dpm-state-ac} but on BAT mode.
21700 Defaults to @samp{"battery"}.
21704 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
21705 Radeon DPM performance level. Alternatives are auto, low, high.
21707 Defaults to @samp{"auto"}.
21711 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
21712 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
21714 Defaults to @samp{"auto"}.
21718 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
21719 Wifi power saving mode.
21721 Defaults to @samp{#f}.
21725 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
21726 Same as @code{wifi-power-ac?} but on BAT mode.
21728 Defaults to @samp{#t}.
21732 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
21733 Disable wake on LAN.
21735 Defaults to @samp{#t}.
21739 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
21740 Timeout duration in seconds before activating audio power saving on
21741 Intel HDA and AC97 devices. A value of 0 disables power saving.
21743 Defaults to @samp{0}.
21747 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
21748 Same as @code{sound-powersave-ac} but on BAT mode.
21750 Defaults to @samp{1}.
21754 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
21755 Disable controller in powersaving mode on Intel HDA devices.
21757 Defaults to @samp{#t}.
21761 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
21762 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
21763 powered on again by releasing (and reinserting) the eject lever or by
21764 pressing the disc eject button on newer models.
21766 Defaults to @samp{#f}.
21770 @deftypevr {@code{tlp-configuration} parameter} string bay-device
21771 Name of the optical drive device to power off.
21773 Defaults to @samp{"sr0"}.
21777 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
21778 Runtime Power Management for PCI(e) bus devices. Alternatives are on
21781 Defaults to @samp{"on"}.
21785 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
21786 Same as @code{runtime-pm-ac} but on BAT mode.
21788 Defaults to @samp{"auto"}.
21792 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
21793 Runtime Power Management for all PCI(e) bus devices, except blacklisted
21796 Defaults to @samp{#t}.
21800 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
21801 Exclude specified PCI(e) device addresses from Runtime Power Management.
21803 Defaults to @samp{disabled}.
21807 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
21808 Exclude PCI(e) devices assigned to the specified drivers from Runtime
21813 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
21814 Enable USB autosuspend feature.
21816 Defaults to @samp{#t}.
21820 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
21821 Exclude specified devices from USB autosuspend.
21823 Defaults to @samp{disabled}.
21827 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
21828 Exclude WWAN devices from USB autosuspend.
21830 Defaults to @samp{#t}.
21834 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
21835 Include specified devices into USB autosuspend, even if they are already
21836 excluded by the driver or via @code{usb-blacklist-wwan?}.
21838 Defaults to @samp{disabled}.
21842 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
21843 Enable USB autosuspend before shutdown.
21845 Defaults to @samp{disabled}.
21849 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
21850 Restore radio device state (bluetooth, wifi, wwan) from previous
21851 shutdown on system startup.
21853 Defaults to @samp{#f}.
21858 @cindex CPU frequency scaling with thermald
21859 @subsubheading Thermald daemon
21861 The @code{(gnu services pm)} module provides an interface to
21862 thermald, a CPU frequency scaling service which helps prevent overheating.
21864 @defvr {Scheme Variable} thermald-service-type
21865 This is the service type for
21866 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
21867 Thermal Daemon, which is responsible for controlling the thermal state
21868 of processors and preventing overheating.
21871 @deftp {Data Type} thermald-configuration
21872 Data type representing the configuration of @code{thermald-service-type}.
21875 @item @code{ignore-cpuid-check?} (default: @code{#f})
21876 Ignore cpuid check for supported CPU models.
21878 @item @code{thermald} (default: @var{thermald})
21879 Package object of thermald.
21884 @node Audio Services
21885 @subsection Audio Services
21887 The @code{(gnu services audio)} module provides a service to start MPD
21888 (the Music Player Daemon).
21891 @subsubheading Music Player Daemon
21893 The Music Player Daemon (MPD) is a service that can play music while
21894 being controlled from the local machine or over the network by a variety
21897 The following example shows how one might run @code{mpd} as user
21898 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
21901 (service mpd-service-type
21907 @defvr {Scheme Variable} mpd-service-type
21908 The service type for @command{mpd}
21911 @deftp {Data Type} mpd-configuration
21912 Data type representing the configuration of @command{mpd}.
21915 @item @code{user} (default: @code{"mpd"})
21916 The user to run mpd as.
21918 @item @code{music-dir} (default: @code{"~/Music"})
21919 The directory to scan for music files.
21921 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
21922 The directory to store playlists.
21924 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
21925 The location of the music database.
21927 @item @code{state-file} (default: @code{"~/.mpd/state"})
21928 The location of the file that stores current MPD's state.
21930 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
21931 The location of the sticker database.
21933 @item @code{port} (default: @code{"6600"})
21934 The port to run mpd on.
21936 @item @code{address} (default: @code{"any"})
21937 The address that mpd will bind to. To use a Unix domain socket,
21938 an absolute path can be specified here.
21943 @node Virtualization Services
21944 @subsection Virtualization services
21946 The @code{(gnu services virtualization)} module provides services for
21947 the libvirt and virtlog daemons, as well as other virtualization-related
21950 @subsubheading Libvirt daemon
21951 @code{libvirtd} is the server side daemon component of the libvirt
21952 virtualization management system. This daemon runs on host servers
21953 and performs required management tasks for virtualized guests.
21955 @deffn {Scheme Variable} libvirt-service-type
21956 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
21957 Its value must be a @code{libvirt-configuration}.
21960 (service libvirt-service-type
21961 (libvirt-configuration
21962 (unix-sock-group "libvirt")
21963 (tls-port "16555")))
21967 @c Auto-generated with (generate-libvirt-documentation)
21968 Available @code{libvirt-configuration} fields are:
21970 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
21975 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
21976 Flag listening for secure TLS connections on the public TCP/IP port.
21977 must set @code{listen} for this to have any effect.
21979 It is necessary to setup a CA and issue server certificates before using
21982 Defaults to @samp{#t}.
21986 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
21987 Listen for unencrypted TCP connections on the public TCP/IP port. must
21988 set @code{listen} for this to have any effect.
21990 Using the TCP socket requires SASL authentication by default. Only SASL
21991 mechanisms which support data encryption are allowed. This is
21992 DIGEST_MD5 and GSSAPI (Kerberos5)
21994 Defaults to @samp{#f}.
21998 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
21999 Port for accepting secure TLS connections This can be a port number, or
22002 Defaults to @samp{"16514"}.
22006 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
22007 Port for accepting insecure TCP connections This can be a port number,
22010 Defaults to @samp{"16509"}.
22014 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
22015 IP address or hostname used for client connections.
22017 Defaults to @samp{"0.0.0.0"}.
22021 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
22022 Flag toggling mDNS advertisement of the libvirt service.
22024 Alternatively can disable for all services on a host by stopping the
22027 Defaults to @samp{#f}.
22031 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
22032 Default mDNS advertisement name. This must be unique on the immediate
22035 Defaults to @samp{"Virtualization Host <hostname>"}.
22039 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
22040 UNIX domain socket group ownership. This can be used to allow a
22041 'trusted' set of users access to management capabilities without
22044 Defaults to @samp{"root"}.
22048 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
22049 UNIX socket permissions for the R/O socket. This is used for monitoring
22052 Defaults to @samp{"0777"}.
22056 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
22057 UNIX socket permissions for the R/W socket. Default allows only root.
22058 If PolicyKit is enabled on the socket, the default will change to allow
22059 everyone (eg, 0777)
22061 Defaults to @samp{"0770"}.
22065 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
22066 UNIX socket permissions for the admin socket. Default allows only owner
22067 (root), do not change it unless you are sure to whom you are exposing
22070 Defaults to @samp{"0777"}.
22074 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
22075 The directory in which sockets will be found/created.
22077 Defaults to @samp{"/var/run/libvirt"}.
22081 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
22082 Authentication scheme for UNIX read-only sockets. By default socket
22083 permissions allow anyone to connect
22085 Defaults to @samp{"polkit"}.
22089 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
22090 Authentication scheme for UNIX read-write sockets. By default socket
22091 permissions only allow root. If PolicyKit support was compiled into
22092 libvirt, the default will be to use 'polkit' auth.
22094 Defaults to @samp{"polkit"}.
22098 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
22099 Authentication scheme for TCP sockets. If you don't enable SASL, then
22100 all TCP traffic is cleartext. Don't do this outside of a dev/test
22103 Defaults to @samp{"sasl"}.
22107 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
22108 Authentication scheme for TLS sockets. TLS sockets already have
22109 encryption provided by the TLS layer, and limited authentication is done
22112 It is possible to make use of any SASL authentication mechanism as well,
22113 by using 'sasl' for this option
22115 Defaults to @samp{"none"}.
22119 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
22120 API access control scheme.
22122 By default an authenticated user is allowed access to all APIs. Access
22123 drivers can place restrictions on this.
22125 Defaults to @samp{()}.
22129 @deftypevr {@code{libvirt-configuration} parameter} string key-file
22130 Server key file path. If set to an empty string, then no private key is
22133 Defaults to @samp{""}.
22137 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
22138 Server key file path. If set to an empty string, then no certificate is
22141 Defaults to @samp{""}.
22145 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
22146 Server key file path. If set to an empty string, then no CA certificate
22149 Defaults to @samp{""}.
22153 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
22154 Certificate revocation list path. If set to an empty string, then no
22157 Defaults to @samp{""}.
22161 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
22162 Disable verification of our own server certificates.
22164 When libvirtd starts it performs some sanity checks against its own
22167 Defaults to @samp{#f}.
22171 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
22172 Disable verification of client certificates.
22174 Client certificate verification is the primary authentication mechanism.
22175 Any client which does not present a certificate signed by the CA will be
22178 Defaults to @samp{#f}.
22182 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
22183 Whitelist of allowed x509 Distinguished Name.
22185 Defaults to @samp{()}.
22189 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
22190 Whitelist of allowed SASL usernames. The format for username depends on
22191 the SASL authentication mechanism.
22193 Defaults to @samp{()}.
22197 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
22198 Override the compile time default TLS priority string. The default is
22199 usually "NORMAL" unless overridden at build time. Only set this is it
22200 is desired for libvirt to deviate from the global default settings.
22202 Defaults to @samp{"NORMAL"}.
22206 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
22207 Maximum number of concurrent client connections to allow over all
22210 Defaults to @samp{5000}.
22214 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
22215 Maximum length of queue of connections waiting to be accepted by the
22216 daemon. Note, that some protocols supporting retransmission may obey
22217 this so that a later reattempt at connection succeeds.
22219 Defaults to @samp{1000}.
22223 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
22224 Maximum length of queue of accepted but not yet authenticated clients.
22225 Set this to zero to turn this feature off
22227 Defaults to @samp{20}.
22231 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
22232 Number of workers to start up initially.
22234 Defaults to @samp{5}.
22238 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
22239 Maximum number of worker threads.
22241 If the number of active clients exceeds @code{min-workers}, then more
22242 threads are spawned, up to max_workers limit. Typically you'd want
22243 max_workers to equal maximum number of clients allowed.
22245 Defaults to @samp{20}.
22249 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
22250 Number of priority workers. If all workers from above pool are stuck,
22251 some calls marked as high priority (notably domainDestroy) can be
22252 executed in this pool.
22254 Defaults to @samp{5}.
22258 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
22259 Total global limit on concurrent RPC calls.
22261 Defaults to @samp{20}.
22265 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
22266 Limit on concurrent requests from a single client connection. To avoid
22267 one client monopolizing the server this should be a small fraction of
22268 the global max_requests and max_workers parameter.
22270 Defaults to @samp{5}.
22274 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
22275 Same as @code{min-workers} but for the admin interface.
22277 Defaults to @samp{1}.
22281 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
22282 Same as @code{max-workers} but for the admin interface.
22284 Defaults to @samp{5}.
22288 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
22289 Same as @code{max-clients} but for the admin interface.
22291 Defaults to @samp{5}.
22295 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
22296 Same as @code{max-queued-clients} but for the admin interface.
22298 Defaults to @samp{5}.
22302 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
22303 Same as @code{max-client-requests} but for the admin interface.
22305 Defaults to @samp{5}.
22309 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
22310 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22312 Defaults to @samp{3}.
22316 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
22319 A filter allows to select a different logging level for a given category
22320 of logs The format for a filter is one of:
22331 where @code{name} is a string which is matched against the category
22332 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22333 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22334 be a substring of the full category name, in order to match multiple
22335 similar categories), the optional "+" prefix tells libvirt to log stack
22336 trace for each message matching name, and @code{x} is the minimal level
22337 where matching messages should be logged:
22354 Multiple filters can be defined in a single filters statement, they just
22355 need to be separated by spaces.
22357 Defaults to @samp{"3:remote 4:event"}.
22361 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
22364 An output is one of the places to save logging information. The format
22365 for an output can be:
22369 output goes to stderr
22371 @item x:syslog:name
22372 use syslog for the output and use the given name as the ident
22374 @item x:file:file_path
22375 output to a file, with the given filepath
22378 output to journald logging system
22382 In all case the x prefix is the minimal level, acting as a filter
22399 Multiple outputs can be defined, they just need to be separated by
22402 Defaults to @samp{"3:stderr"}.
22406 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
22407 Allows usage of the auditing subsystem to be altered
22411 0: disable all auditing
22414 1: enable auditing, only if enabled on host
22417 2: enable auditing, and exit if disabled on host.
22421 Defaults to @samp{1}.
22425 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
22426 Send audit messages via libvirt logging infrastructure.
22428 Defaults to @samp{#f}.
22432 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
22433 Host UUID. UUID must not have all digits be the same.
22435 Defaults to @samp{""}.
22439 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
22440 Source to read host UUID.
22444 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
22447 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
22451 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
22454 Defaults to @samp{"smbios"}.
22458 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
22459 A keepalive message is sent to a client after @code{keepalive_interval}
22460 seconds of inactivity to check if the client is still responding. If
22461 set to -1, libvirtd will never send keepalive requests; however clients
22462 can still send them and the daemon will send responses.
22464 Defaults to @samp{5}.
22468 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
22469 Maximum number of keepalive messages that are allowed to be sent to the
22470 client without getting any response before the connection is considered
22473 In other words, the connection is automatically closed approximately
22474 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
22475 the last message received from the client. When @code{keepalive-count}
22476 is set to 0, connections will be automatically closed after
22477 @code{keepalive-interval} seconds of inactivity without sending any
22478 keepalive messages.
22480 Defaults to @samp{5}.
22484 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
22485 Same as above but for admin interface.
22487 Defaults to @samp{5}.
22491 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
22492 Same as above but for admin interface.
22494 Defaults to @samp{5}.
22498 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
22499 Timeout for Open vSwitch calls.
22501 The @code{ovs-vsctl} utility is used for the configuration and its
22502 timeout option is set by default to 5 seconds to avoid potential
22503 infinite waits blocking libvirt.
22505 Defaults to @samp{5}.
22509 @c %end of autogenerated docs
22511 @subsubheading Virtlog daemon
22512 The virtlogd service is a server side daemon component of libvirt that is
22513 used to manage logs from virtual machine consoles.
22515 This daemon is not used directly by libvirt client applications, rather it
22516 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
22517 standalone daemon, the main @code{libvirtd} daemon can be restarted without
22518 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
22519 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
22521 @deffn {Scheme Variable} virtlog-service-type
22522 This is the type of the virtlog daemon.
22523 Its value must be a @code{virtlog-configuration}.
22526 (service virtlog-service-type
22527 (virtlog-configuration
22528 (max-clients 1000)))
22532 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
22533 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
22535 Defaults to @samp{3}.
22539 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
22542 A filter allows to select a different logging level for a given category
22543 of logs The format for a filter is one of:
22554 where @code{name} is a string which is matched against the category
22555 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
22556 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
22557 be a substring of the full category name, in order to match multiple
22558 similar categories), the optional "+" prefix tells libvirt to log stack
22559 trace for each message matching name, and @code{x} is the minimal level
22560 where matching messages should be logged:
22577 Multiple filters can be defined in a single filters statement, they just
22578 need to be separated by spaces.
22580 Defaults to @samp{"3:remote 4:event"}.
22584 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
22587 An output is one of the places to save logging information The format
22588 for an output can be:
22592 output goes to stderr
22594 @item x:syslog:name
22595 use syslog for the output and use the given name as the ident
22597 @item x:file:file_path
22598 output to a file, with the given filepath
22601 output to journald logging system
22605 In all case the x prefix is the minimal level, acting as a filter
22622 Multiple outputs can be defined, they just need to be separated by
22625 Defaults to @samp{"3:stderr"}.
22629 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
22630 Maximum number of concurrent client connections to allow over all
22633 Defaults to @samp{1024}.
22637 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
22638 Maximum file size before rolling over.
22640 Defaults to @samp{2MB}
22644 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
22645 Maximum number of backup files to keep.
22647 Defaults to @samp{3}
22651 @subsubheading Transparent Emulation with QEMU
22654 @cindex @code{binfmt_misc}
22655 @code{qemu-binfmt-service-type} provides support for transparent
22656 emulation of program binaries built for different architectures---e.g.,
22657 it allows you to transparently execute an ARMv7 program on an x86_64
22658 machine. It achieves this by combining the @uref{https://www.qemu.org,
22659 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
22661 @defvr {Scheme Variable} qemu-binfmt-service-type
22662 This is the type of the QEMU/binfmt service for transparent emulation.
22663 Its value must be a @code{qemu-binfmt-configuration} object, which
22664 specifies the QEMU package to use as well as the architecture we want to
22668 (service qemu-binfmt-service-type
22669 (qemu-binfmt-configuration
22670 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
22673 In this example, we enable transparent emulation for the ARM and aarch64
22674 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
22675 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
22676 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
22679 @deftp {Data Type} qemu-binfmt-configuration
22680 This is the configuration for the @code{qemu-binfmt} service.
22683 @item @code{platforms} (default: @code{'()})
22684 The list of emulated QEMU platforms. Each item must be a @dfn{platform
22685 object} as returned by @code{lookup-qemu-platforms} (see below).
22687 @item @code{guix-support?} (default: @code{#f})
22688 When it is true, QEMU and all its dependencies are added to the build
22689 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
22690 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
22691 handlers to be used within the build environment, which in turn means
22692 that you can transparently build programs for another architecture.
22694 For example, let's suppose you're on an x86_64 machine and you have this
22698 (service qemu-binfmt-service-type
22699 (qemu-binfmt-configuration
22700 (platforms (lookup-qemu-platforms "arm"))
22701 (guix-support? #t)))
22707 guix build -s armhf-linux inkscape
22711 and it will build Inkscape for ARMv7 @emph{as if it were a native
22712 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
22713 if you'd like to test a package build for an architecture you don't have
22716 @item @code{qemu} (default: @code{qemu})
22717 The QEMU package to use.
22721 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
22722 Return the list of QEMU platform objects corresponding to
22723 @var{platforms}@dots{}. @var{platforms} must be a list of strings
22724 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
22725 @code{"mips64el"}, and so on.
22728 @deffn {Scheme Procedure} qemu-platform? @var{obj}
22729 Return true if @var{obj} is a platform object.
22732 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
22733 Return the name of @var{platform}---a string such as @code{"arm"}.
22736 @node Version Control Services
22737 @subsection Version Control Services
22739 The @code{(gnu services version-control)} module provides a service to
22740 allow remote access to local Git repositories. There are three options:
22741 the @code{git-daemon-service}, which provides access to repositories via
22742 the @code{git://} unsecured TCP-based protocol, extending the
22743 @code{nginx} web server to proxy some requests to
22744 @code{git-http-backend}, or providing a web interface with
22745 @code{cgit-service-type}.
22747 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
22749 Return a service that runs @command{git daemon}, a simple TCP server to
22750 expose repositories over the Git protocol for anonymous access.
22752 The optional @var{config} argument should be a
22753 @code{<git-daemon-configuration>} object, by default it allows read-only
22754 access to exported@footnote{By creating the magic file
22755 "git-daemon-export-ok" in the repository directory.} repositories under
22760 @deftp {Data Type} git-daemon-configuration
22761 Data type representing the configuration for @code{git-daemon-service}.
22764 @item @code{package} (default: @var{git})
22765 Package object of the Git distributed version control system.
22767 @item @code{export-all?} (default: @var{#f})
22768 Whether to allow access for all Git repositories, even if they do not
22769 have the @file{git-daemon-export-ok} file.
22771 @item @code{base-path} (default: @file{/srv/git})
22772 Whether to remap all the path requests as relative to the given path.
22773 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
22774 then if you later try to pull @code{git://example.com/hello.git}, git
22775 daemon will interpret the path as @code{/srv/git/hello.git}.
22777 @item @code{user-path} (default: @var{#f})
22778 Whether to allow @code{~user} notation to be used in requests. When
22779 specified with empty string, requests to @code{git://host/~alice/foo} is
22780 taken as a request to access @code{foo} repository in the home directory
22781 of user @code{alice}. If @var{(user-path "path")} is specified, the
22782 same request is taken as a request to access @code{path/foo} repository
22783 in the home directory of user @code{alice}.
22785 @item @code{listen} (default: @var{'()})
22786 Whether to listen on specific IP addresses or hostnames, defaults to
22789 @item @code{port} (default: @var{#f})
22790 Whether to listen on an alternative port, which defaults to 9418.
22792 @item @code{whitelist} (default: @var{'()})
22793 If not empty, only allow access to this list of directories.
22795 @item @code{extra-options} (default: @var{'()})
22796 Extra options will be passed to @code{git daemon}, please run
22797 @command{man git-daemon} for more information.
22802 The @code{git://} protocol lacks authentication. When you pull from a
22803 repository fetched via @code{git://}, you don't know whether the data you
22804 receive was modified or is even coming from the specified host, and your
22805 connection is subject to eavesdropping. It's better to use an authenticated
22806 and encrypted transport, such as @code{https}. Although Git allows you
22807 to serve repositories using unsophisticated file-based web servers,
22808 there is a faster protocol implemented by the @code{git-http-backend}
22809 program. This program is the back-end of a proper Git web service. It
22810 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
22811 on running the necessary @code{fcgiwrap} daemon.
22813 Guix has a separate configuration data type for serving Git repositories
22816 @deftp {Data Type} git-http-configuration
22817 Data type representing the configuration for @code{git-http-service}.
22820 @item @code{package} (default: @var{git})
22821 Package object of the Git distributed version control system.
22823 @item @code{git-root} (default: @file{/srv/git})
22824 Directory containing the Git repositories to expose to the world.
22826 @item @code{export-all?} (default: @var{#f})
22827 Whether to expose access for all Git repositories in @var{git-root},
22828 even if they do not have the @file{git-daemon-export-ok} file.
22830 @item @code{uri-path} (default: @file{/git/})
22831 Path prefix for Git access. With the default @code{/git/} prefix, this
22832 will map @code{http://@var{server}/git/@var{repo}.git} to
22833 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
22834 with this prefix are not passed on to this Git instance.
22836 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
22837 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
22842 There is no @code{git-http-service-type}, currently; instead you can
22843 create an @code{nginx-location-configuration} from a
22844 @code{git-http-configuration} and then add that location to a web
22847 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
22848 [config=(git-http-configuration)]
22849 Compute an @code{nginx-location-configuration} that corresponds to the
22850 given Git http configuration. An example nginx service definition to
22851 serve the default @file{/srv/git} over HTTPS might be:
22854 (service nginx-service-type
22855 (nginx-configuration
22858 (nginx-server-configuration
22859 (listen '("443 ssl"))
22860 (server-name "git.my-host.org")
22862 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
22863 (ssl-certificate-key
22864 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
22867 (git-http-nginx-location-configuration
22868 (git-http-configuration (uri-path "/"))))))))))
22871 This example assumes that you are using Let's Encrypt to get your TLS
22872 certificate. @xref{Certificate Services}. The default @code{certbot}
22873 service will redirect all HTTP traffic on @code{git.my-host.org} to
22874 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
22875 system services. @xref{Web Services}.
22878 @subsubheading Cgit Service
22880 @cindex Cgit service
22881 @cindex Git, web interface
22882 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
22883 repositories written in C.
22885 The following example will configure the service with default values.
22886 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
22889 (service cgit-service-type)
22892 The @code{file-object} type designates either a file-like object
22893 (@pxref{G-Expressions, file-like objects}) or a string.
22895 @c %start of fragment
22897 Available @code{cgit-configuration} fields are:
22899 @deftypevr {@code{cgit-configuration} parameter} package package
22904 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
22905 NGINX configuration.
22909 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
22910 Specifies a command which will be invoked to format the content of about
22911 pages (both top-level and for each repository).
22913 Defaults to @samp{""}.
22917 @deftypevr {@code{cgit-configuration} parameter} string agefile
22918 Specifies a path, relative to each repository path, which can be used to
22919 specify the date and time of the youngest commit in the repository.
22921 Defaults to @samp{""}.
22925 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
22926 Specifies a command that will be invoked for authenticating repository
22929 Defaults to @samp{""}.
22933 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
22934 Flag which, when set to @samp{age}, enables date ordering in the branch
22935 ref list, and when set @samp{name} enables ordering by branch name.
22937 Defaults to @samp{"name"}.
22941 @deftypevr {@code{cgit-configuration} parameter} string cache-root
22942 Path used to store the cgit cache entries.
22944 Defaults to @samp{"/var/cache/cgit"}.
22948 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
22949 Number which specifies the time-to-live, in minutes, for the cached
22950 version of repository pages accessed with a fixed SHA1.
22952 Defaults to @samp{-1}.
22956 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
22957 Number which specifies the time-to-live, in minutes, for the cached
22958 version of repository pages accessed without a fixed SHA1.
22960 Defaults to @samp{5}.
22964 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
22965 Number which specifies the time-to-live, in minutes, for the cached
22966 version of the repository summary page.
22968 Defaults to @samp{5}.
22972 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
22973 Number which specifies the time-to-live, in minutes, for the cached
22974 version of the repository index page.
22976 Defaults to @samp{5}.
22980 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
22981 Number which specifies the time-to-live, in minutes, for the result of
22982 scanning a path for Git repositories.
22984 Defaults to @samp{15}.
22988 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
22989 Number which specifies the time-to-live, in minutes, for the cached
22990 version of the repository about page.
22992 Defaults to @samp{15}.
22996 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
22997 Number which specifies the time-to-live, in minutes, for the cached
22998 version of snapshots.
23000 Defaults to @samp{5}.
23004 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
23005 The maximum number of entries in the cgit cache. When set to @samp{0},
23006 caching is disabled.
23008 Defaults to @samp{0}.
23012 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
23013 Sort items in the repo list case sensitively.
23015 Defaults to @samp{#t}.
23019 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
23020 List of common prefixes which, when combined with a repository URL,
23021 generates valid clone URLs for the repository.
23023 Defaults to @samp{()}.
23027 @deftypevr {@code{cgit-configuration} parameter} list clone-url
23028 List of @code{clone-url} templates.
23030 Defaults to @samp{()}.
23034 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
23035 Command which will be invoked to format commit messages.
23037 Defaults to @samp{""}.
23041 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
23042 Flag which, when set to @samp{date}, enables strict date ordering in the
23043 commit log, and when set to @samp{topo} enables strict topological
23046 Defaults to @samp{"git log"}.
23050 @deftypevr {@code{cgit-configuration} parameter} file-object css
23051 URL which specifies the css document to include in all cgit pages.
23053 Defaults to @samp{"/share/cgit/cgit.css"}.
23057 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
23058 Specifies a command which will be invoked to format names and email
23059 address of committers, authors, and taggers, as represented in various
23060 places throughout the cgit interface.
23062 Defaults to @samp{""}.
23066 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
23067 Flag which, when set to @samp{#t}, will make cgit generate a HTML
23068 fragment suitable for embedding in other HTML pages.
23070 Defaults to @samp{#f}.
23074 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
23075 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
23076 commit history graph to the left of the commit messages in the
23077 repository log page.
23079 Defaults to @samp{#f}.
23083 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
23084 Flag which, when set to @samp{#t}, allows all filter settings to be
23085 overridden in repository-specific cgitrc files.
23087 Defaults to @samp{#f}.
23091 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
23092 Flag which, when set to @samp{#t}, allows users to follow a file in the
23095 Defaults to @samp{#f}.
23099 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
23100 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
23103 Defaults to @samp{#t}.
23107 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
23108 Flag which, when set to @samp{#t}, will make cgit generate extra links
23109 "summary", "commit", "tree" for each repo in the repository index.
23111 Defaults to @samp{#f}.
23115 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
23116 Flag which, when set to @samp{#t}, will make cgit display the owner of
23117 each repo in the repository index.
23119 Defaults to @samp{#t}.
23123 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
23124 Flag which, when set to @samp{#t}, will make cgit print the number of
23125 modified files for each commit on the repository log page.
23127 Defaults to @samp{#f}.
23131 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
23132 Flag which, when set to @samp{#t}, will make cgit print the number of
23133 added and removed lines for each commit on the repository log page.
23135 Defaults to @samp{#f}.
23139 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
23140 Flag which, when set to @code{#t}, will make cgit display remote
23141 branches in the summary and refs views.
23143 Defaults to @samp{#f}.
23147 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
23148 Flag which, when set to @code{1}, will make cgit use the subject of the
23149 parent commit as link text when generating links to parent commits in
23152 Defaults to @samp{#f}.
23156 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
23157 Flag which, when set to @samp{#t}, will make cgit use the subject of the
23158 parent commit as link text when generating links to parent commits in
23161 Defaults to @samp{#f}.
23165 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
23166 Flag which, when set to @samp{#t}, will make cgit generate linenumber
23167 links for plaintext blobs printed in the tree view.
23169 Defaults to @samp{#t}.
23173 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
23174 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
23175 set any repo specific settings.
23177 Defaults to @samp{#f}.
23181 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
23182 URL used as link to a shortcut icon for cgit.
23184 Defaults to @samp{"/favicon.ico"}.
23188 @deftypevr {@code{cgit-configuration} parameter} string footer
23189 The content of the file specified with this option will be included
23190 verbatim at the bottom of all pages (i.e.@: it replaces the standard
23191 "generated by..."@: message).
23193 Defaults to @samp{""}.
23197 @deftypevr {@code{cgit-configuration} parameter} string head-include
23198 The content of the file specified with this option will be included
23199 verbatim in the HTML HEAD section on all pages.
23201 Defaults to @samp{""}.
23205 @deftypevr {@code{cgit-configuration} parameter} string header
23206 The content of the file specified with this option will be included
23207 verbatim at the top of all pages.
23209 Defaults to @samp{""}.
23213 @deftypevr {@code{cgit-configuration} parameter} file-object include
23214 Name of a configfile to include before the rest of the current config-
23217 Defaults to @samp{""}.
23221 @deftypevr {@code{cgit-configuration} parameter} string index-header
23222 The content of the file specified with this option will be included
23223 verbatim above the repository index.
23225 Defaults to @samp{""}.
23229 @deftypevr {@code{cgit-configuration} parameter} string index-info
23230 The content of the file specified with this option will be included
23231 verbatim below the heading on the repository index page.
23233 Defaults to @samp{""}.
23237 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
23238 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
23239 in the servers timezone.
23241 Defaults to @samp{#f}.
23245 @deftypevr {@code{cgit-configuration} parameter} file-object logo
23246 URL which specifies the source of an image which will be used as a logo
23249 Defaults to @samp{"/share/cgit/cgit.png"}.
23253 @deftypevr {@code{cgit-configuration} parameter} string logo-link
23254 URL loaded when clicking on the cgit logo image.
23256 Defaults to @samp{""}.
23260 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
23261 Command which will be invoked to format the Owner column of the main
23264 Defaults to @samp{""}.
23268 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
23269 Number of items to display in atom feeds view.
23271 Defaults to @samp{10}.
23275 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
23276 Number of entries to list per page in "log" view.
23278 Defaults to @samp{50}.
23282 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
23283 Number of commit message characters to display in "log" view.
23285 Defaults to @samp{80}.
23289 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
23290 Specifies the number of entries to list per page on the repository index
23293 Defaults to @samp{50}.
23297 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
23298 Specifies the maximum number of repo description characters to display
23299 on the repository index page.
23301 Defaults to @samp{80}.
23305 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
23306 Specifies the maximum size of a blob to display HTML for in KBytes.
23308 Defaults to @samp{0}.
23312 @deftypevr {@code{cgit-configuration} parameter} string max-stats
23313 Maximum statistics period. Valid values are @samp{week},@samp{month},
23314 @samp{quarter} and @samp{year}.
23316 Defaults to @samp{""}.
23320 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
23321 Mimetype for the specified filename extension.
23323 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
23324 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
23325 "image/png") (svg "image/svg+xml"))}.
23329 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
23330 Specifies the file to use for automatic mimetype lookup.
23332 Defaults to @samp{""}.
23336 @deftypevr {@code{cgit-configuration} parameter} string module-link
23337 Text which will be used as the formatstring for a hyperlink when a
23338 submodule is printed in a directory listing.
23340 Defaults to @samp{""}.
23344 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
23345 If set to the value @samp{#t} caching will be disabled.
23347 Defaults to @samp{#f}.
23351 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
23352 If set to @samp{#t} showing full author email addresses will be
23355 Defaults to @samp{#f}.
23359 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
23360 Flag which, when set to @samp{#t}, will make cgit omit the standard
23361 header on all pages.
23363 Defaults to @samp{#f}.
23367 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
23368 A list of subdirectories inside of @code{repository-directory}, relative
23369 to it, that should loaded as Git repositories. An empty list means that
23370 all subdirectories will be loaded.
23372 Defaults to @samp{()}.
23376 @deftypevr {@code{cgit-configuration} parameter} file-object readme
23377 Text which will be used as default value for @code{cgit-repo-readme}.
23379 Defaults to @samp{""}.
23383 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
23384 If set to @code{#t} and @code{repository-directory} is enabled, if any
23385 repositories are found with a suffix of @code{.git}, this suffix will be
23386 removed for the URL and name.
23388 Defaults to @samp{#f}.
23392 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
23393 Maximum number of files to consider when detecting renames.
23395 Defaults to @samp{-1}.
23399 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
23400 The way in which repositories in each section are sorted.
23402 Defaults to @samp{""}.
23406 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
23407 Text used as content for the @code{robots} meta-tag.
23409 Defaults to @samp{("noindex" "nofollow")}.
23413 @deftypevr {@code{cgit-configuration} parameter} string root-desc
23414 Text printed below the heading on the repository index page.
23416 Defaults to @samp{"a fast webinterface for the git dscm"}.
23420 @deftypevr {@code{cgit-configuration} parameter} string root-readme
23421 The content of the file specified with this option will be included
23422 verbatim below thef "about" link on the repository index page.
23424 Defaults to @samp{""}.
23428 @deftypevr {@code{cgit-configuration} parameter} string root-title
23429 Text printed as heading on the repository index page.
23431 Defaults to @samp{""}.
23435 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
23436 If set to @samp{#t} and repository-directory is enabled,
23437 repository-directory will recurse into directories whose name starts
23438 with a period. Otherwise, repository-directory will stay away from such
23439 directories, considered as "hidden". Note that this does not apply to
23440 the ".git" directory in non-bare repos.
23442 Defaults to @samp{#f}.
23446 @deftypevr {@code{cgit-configuration} parameter} list snapshots
23447 Text which specifies the default set of snapshot formats that cgit
23448 generates links for.
23450 Defaults to @samp{()}.
23454 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
23455 Name of the directory to scan for repositories (represents
23458 Defaults to @samp{"/srv/git"}.
23462 @deftypevr {@code{cgit-configuration} parameter} string section
23463 The name of the current repository section - all repositories defined
23464 after this option will inherit the current section name.
23466 Defaults to @samp{""}.
23470 @deftypevr {@code{cgit-configuration} parameter} string section-sort
23471 Flag which, when set to @samp{1}, will sort the sections on the
23472 repository listing by name.
23474 Defaults to @samp{""}.
23478 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
23479 A number which, if defined prior to repository-directory, specifies how
23480 many path elements from each repo path to use as a default section name.
23482 Defaults to @samp{0}.
23486 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
23487 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
23490 Defaults to @samp{#f}.
23494 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
23495 Specifies a command which will be invoked to format plaintext blobs in
23498 Defaults to @samp{""}.
23502 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
23503 Specifies the number of branches to display in the repository "summary"
23506 Defaults to @samp{10}.
23510 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
23511 Specifies the number of log entries to display in the repository
23514 Defaults to @samp{10}.
23518 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
23519 Specifies the number of tags to display in the repository "summary"
23522 Defaults to @samp{10}.
23526 @deftypevr {@code{cgit-configuration} parameter} string strict-export
23527 Filename which, if specified, needs to be present within the repository
23528 for cgit to allow access to that repository.
23530 Defaults to @samp{""}.
23534 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
23535 URL which, if specified, will be used as root for all cgit links.
23537 Defaults to @samp{"/"}.
23541 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
23542 A list of @dfn{cgit-repo} records to use with config.
23544 Defaults to @samp{()}.
23546 Available @code{repository-cgit-configuration} fields are:
23548 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
23549 A mask of snapshot formats for this repo that cgit generates links for,
23550 restricted by the global @code{snapshots} setting.
23552 Defaults to @samp{()}.
23556 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
23557 Override the default @code{source-filter}.
23559 Defaults to @samp{""}.
23563 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
23564 The relative URL used to access the repository.
23566 Defaults to @samp{""}.
23570 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
23571 Override the default @code{about-filter}.
23573 Defaults to @samp{""}.
23577 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
23578 Flag which, when set to @samp{age}, enables date ordering in the branch
23579 ref list, and when set to @samp{name} enables ordering by branch name.
23581 Defaults to @samp{""}.
23585 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
23586 A list of URLs which can be used to clone repo.
23588 Defaults to @samp{()}.
23592 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
23593 Override the default @code{commit-filter}.
23595 Defaults to @samp{""}.
23599 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
23600 Flag which, when set to @samp{date}, enables strict date ordering in the
23601 commit log, and when set to @samp{topo} enables strict topological
23604 Defaults to @samp{""}.
23608 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
23609 The name of the default branch for this repository. If no such branch
23610 exists in the repository, the first branch name (when sorted) is used as
23611 default instead. By default branch pointed to by HEAD, or "master" if
23612 there is no suitable HEAD.
23614 Defaults to @samp{""}.
23618 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
23619 The value to show as repository description.
23621 Defaults to @samp{""}.
23625 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
23626 The value to show as repository homepage.
23628 Defaults to @samp{""}.
23632 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
23633 Override the default @code{email-filter}.
23635 Defaults to @samp{""}.
23639 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
23640 A flag which can be used to disable the global setting
23641 @code{enable-commit-graph?}.
23643 Defaults to @samp{disabled}.
23647 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
23648 A flag which can be used to disable the global setting
23649 @code{enable-log-filecount?}.
23651 Defaults to @samp{disabled}.
23655 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
23656 A flag which can be used to disable the global setting
23657 @code{enable-log-linecount?}.
23659 Defaults to @samp{disabled}.
23663 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
23664 Flag which, when set to @code{#t}, will make cgit display remote
23665 branches in the summary and refs views.
23667 Defaults to @samp{disabled}.
23671 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
23672 A flag which can be used to override the global setting
23673 @code{enable-subject-links?}.
23675 Defaults to @samp{disabled}.
23679 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
23680 A flag which can be used to override the global setting
23681 @code{enable-html-serving?}.
23683 Defaults to @samp{disabled}.
23687 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
23688 Flag which, when set to @code{#t}, hides the repository from the
23691 Defaults to @samp{#f}.
23695 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
23696 Flag which, when set to @samp{#t}, ignores the repository.
23698 Defaults to @samp{#f}.
23702 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
23703 URL which specifies the source of an image which will be used as a logo
23704 on this repo’s pages.
23706 Defaults to @samp{""}.
23710 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
23711 URL loaded when clicking on the cgit logo image.
23713 Defaults to @samp{""}.
23717 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
23718 Override the default @code{owner-filter}.
23720 Defaults to @samp{""}.
23724 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
23725 Text which will be used as the formatstring for a hyperlink when a
23726 submodule is printed in a directory listing. The arguments for the
23727 formatstring are the path and SHA1 of the submodule commit.
23729 Defaults to @samp{""}.
23733 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
23734 Text which will be used as the formatstring for a hyperlink when a
23735 submodule with the specified subdirectory path is printed in a directory
23738 Defaults to @samp{()}.
23742 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
23743 Override the default maximum statistics period.
23745 Defaults to @samp{""}.
23749 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
23750 The value to show as repository name.
23752 Defaults to @samp{""}.
23756 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
23757 A value used to identify the owner of the repository.
23759 Defaults to @samp{""}.
23763 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
23764 An absolute path to the repository directory.
23766 Defaults to @samp{""}.
23770 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
23771 A path (relative to repo) which specifies a file to include verbatim as
23772 the "About" page for this repo.
23774 Defaults to @samp{""}.
23778 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
23779 The name of the current repository section - all repositories defined
23780 after this option will inherit the current section name.
23782 Defaults to @samp{""}.
23786 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
23787 Extra options will be appended to cgitrc file.
23789 Defaults to @samp{()}.
23795 @deftypevr {@code{cgit-configuration} parameter} list extra-options
23796 Extra options will be appended to cgitrc file.
23798 Defaults to @samp{()}.
23803 @c %end of fragment
23805 However, it could be that you just want to get a @code{cgitrc} up and
23806 running. In that case, you can pass an @code{opaque-cgit-configuration}
23807 as a record to @code{cgit-service-type}. As its name indicates, an
23808 opaque configuration does not have easy reflective capabilities.
23810 Available @code{opaque-cgit-configuration} fields are:
23812 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
23816 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
23817 The contents of the @code{cgitrc}, as a string.
23820 For example, if your @code{cgitrc} is just the empty string, you
23821 could instantiate a cgit service like this:
23824 (service cgit-service-type
23825 (opaque-cgit-configuration
23829 @subsubheading Gitolite Service
23831 @cindex Gitolite service
23832 @cindex Git, hosting
23833 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
23834 repositories on a central server.
23836 Gitolite can handle multiple repositories and users, and supports flexible
23837 configuration of the permissions for the users on the repositories.
23839 The following example will configure Gitolite using the default @code{git}
23840 user, and the provided SSH public key.
23843 (service gitolite-service-type
23844 (gitolite-configuration
23845 (admin-pubkey (plain-file
23847 "ssh-rsa AAAA... guix@@example.com"))))
23850 Gitolite is configured through a special admin repository which you can clone,
23851 for example, if you setup Gitolite on @code{example.com}, you would run the
23852 following command to clone the admin repository.
23855 git clone git@@example.com:gitolite-admin
23858 When the Gitolite service is activated, the provided @code{admin-pubkey} will
23859 be inserted in to the @file{keydir} directory in the gitolite-admin
23860 repository. If this results in a change in the repository, it will be
23861 committed using the message ``gitolite setup by GNU Guix''.
23863 @deftp {Data Type} gitolite-configuration
23864 Data type representing the configuration for @code{gitolite-service-type}.
23867 @item @code{package} (default: @var{gitolite})
23868 Gitolite package to use.
23870 @item @code{user} (default: @var{git})
23871 User to use for Gitolite. This will be user that you use when accessing
23874 @item @code{group} (default: @var{git})
23875 Group to use for Gitolite.
23877 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
23878 Directory in which to store the Gitolite configuration and repositories.
23880 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
23881 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
23882 representing the configuration for Gitolite.
23884 @item @code{admin-pubkey} (default: @var{#f})
23885 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
23886 setup Gitolite. This will be inserted in to the @file{keydir} directory
23887 within the gitolite-admin repository.
23889 To specify the SSH key as a string, use the @code{plain-file} function.
23892 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
23898 @deftp {Data Type} gitolite-rc-file
23899 Data type representing the Gitolite RC file.
23902 @item @code{umask} (default: @code{#o0077})
23903 This controls the permissions Gitolite sets on the repositories and their
23906 A value like @code{#o0027} will give read access to the group used by Gitolite
23907 (by default: @code{git}). This is necessary when using Gitolite with software
23908 like cgit or gitweb.
23910 @item @code{git-config-keys} (default: @code{""})
23911 Gitolite allows you to set git config values using the "config" keyword. This
23912 setting allows control over the config keys to accept.
23914 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
23915 Set the role names allowed to be used by users running the perms command.
23917 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
23918 This setting controls the commands and features to enable within Gitolite.
23924 @node Game Services
23925 @subsection Game Services
23927 @subsubheading The Battle for Wesnoth Service
23929 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
23930 based tactical strategy game, with several single player campaigns, and
23931 multiplayer games (both networked and local).
23933 @defvar {Scheme Variable} wesnothd-service-type
23934 Service type for the wesnothd service. Its value must be a
23935 @code{wesnothd-configuration} object. To run wesnothd in the default
23936 configuration, instantiate it as:
23939 (service wesnothd-service-type)
23943 @deftp {Data Type} wesnothd-configuration
23944 Data type representing the configuration of @command{wesnothd}.
23947 @item @code{package} (default: @code{wesnoth-server})
23948 The wesnoth server package to use.
23950 @item @code{port} (default: @code{15000})
23951 The port to bind the server to.
23955 @node Miscellaneous Services
23956 @subsection Miscellaneous Services
23958 @cindex fingerprint
23959 @subsubheading Fingerprint Service
23961 The @code{(gnu services authentication)} module provides a DBus service to
23962 read and identify fingerprints via a fingerprint sensor.
23964 @defvr {Scheme Variable} fprintd-service-type
23965 The service type for @command{fprintd}, which provides the fingerprint
23966 reading capability.
23969 (service fprintd-service-type)
23974 @subsubheading System Control Service
23976 The @code{(gnu services sysctl)} provides a service to configure kernel
23977 parameters at boot.
23979 @defvr {Scheme Variable} sysctl-service-type
23980 The service type for @command{sysctl}, which modifies kernel parameters
23981 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
23985 (service sysctl-service-type
23986 (sysctl-configuration
23987 (settings '(("net.ipv4.ip_forward" . "1")))))
23991 @deftp {Data Type} sysctl-configuration
23992 The data type representing the configuration of @command{sysctl}.
23995 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
23996 The @command{sysctl} executable to use.
23998 @item @code{settings} (default: @code{'()})
23999 An association list specifies kernel parameters and their values.
24004 @subsubheading PC/SC Smart Card Daemon Service
24006 The @code{(gnu services security-token)} module provides the following service
24007 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
24008 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
24009 manager that coordinates communications with smart card readers, smart cards
24010 and cryptographic tokens that are connected to the system.
24012 @defvr {Scheme Variable} pcscd-service-type
24013 Service type for the @command{pcscd} service. Its value must be a
24014 @code{pcscd-configuration} object. To run pcscd in the default
24015 configuration, instantiate it as:
24018 (service pcscd-service-type)
24022 @deftp {Data Type} pcscd-configuration
24023 The data type representing the configuration of @command{pcscd}.
24026 @item @code{pcsc-lite} (default: @code{pcsc-lite})
24027 The pcsc-lite package that provides pcscd.
24028 @item @code{usb-drivers} (default: @code{(list ccid)})
24029 List of packages that provide USB drivers to pcscd. Drivers are expected to be
24030 under @file{pcsc/drivers} in the store directory of the package.
24035 @subsubheading Lirc Service
24037 The @code{(gnu services lirc)} module provides the following service.
24039 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
24040 [#:device #f] [#:driver #f] [#:config-file #f] @
24041 [#:extra-options '()]
24042 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
24043 decodes infrared signals from remote controls.
24045 Optionally, @var{device}, @var{driver} and @var{config-file}
24046 (configuration file name) may be specified. See @command{lircd} manual
24049 Finally, @var{extra-options} is a list of additional command-line options
24050 passed to @command{lircd}.
24054 @subsubheading Spice Service
24056 The @code{(gnu services spice)} module provides the following service.
24058 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
24059 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
24060 that enables sharing the clipboard with a vm and setting the guest display
24061 resolution when the graphical console window resizes.
24064 @cindex inputattach
24065 @subsubheading inputattach Service
24067 @cindex tablet input, for Xorg
24068 @cindex touchscreen input, for Xorg
24069 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
24070 use input devices such as Wacom tablets, touchscreens, or joysticks with the
24071 Xorg display server.
24073 @deffn {Scheme Variable} inputattach-service-type
24074 Type of a service that runs @command{inputattach} on a device and
24075 dispatches events from it.
24078 @deftp {Data Type} inputattach-configuration
24080 @item @code{device-type} (default: @code{"wacom"})
24081 The type of device to connect to. Run @command{inputattach --help}, from the
24082 @code{inputattach} package, to see the list of supported device types.
24084 @item @code{device} (default: @code{"/dev/ttyS0"})
24085 The device file to connect to the device.
24087 @item @code{log-file} (default: @code{#f})
24088 If true, this must be the name of a file to log messages to.
24092 @subsection Dictionary Services
24094 The @code{(gnu services dict)} module provides the following service:
24096 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
24097 Return a service that runs the @command{dicod} daemon, an implementation
24098 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
24100 The optional @var{config} argument specifies the configuration for
24101 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
24102 default it serves the GNU Collaborative International Dictonary of English.
24104 You can add @command{open localhost} to your @file{~/.dico} file to make
24105 @code{localhost} the default server for @command{dico} client
24106 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
24109 @deftp {Data Type} dicod-configuration
24110 Data type representing the configuration of dicod.
24113 @item @code{dico} (default: @var{dico})
24114 Package object of the GNU Dico dictionary server.
24116 @item @code{interfaces} (default: @var{'("localhost")})
24117 This is the list of IP addresses and ports and possibly socket file
24118 names to listen to (@pxref{Server Settings, @code{listen} directive,,
24119 dico, GNU Dico Manual}).
24121 @item @code{handlers} (default: @var{'()})
24122 List of @code{<dicod-handler>} objects denoting handlers (module instances).
24124 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
24125 List of @code{<dicod-database>} objects denoting dictionaries to be served.
24129 @deftp {Data Type} dicod-handler
24130 Data type representing a dictionary handler (module instance).
24134 Name of the handler (module instance).
24136 @item @code{module} (default: @var{#f})
24137 Name of the dicod module of the handler (instance). If it is @code{#f},
24138 the module has the same name as the handler.
24139 (@pxref{Modules,,, dico, GNU Dico Manual}).
24141 @item @code{options}
24142 List of strings or gexps representing the arguments for the module handler
24146 @deftp {Data Type} dicod-database
24147 Data type representing a dictionary database.
24151 Name of the database, will be used in DICT commands.
24153 @item @code{handler}
24154 Name of the dicod handler (module instance) used by this database
24155 (@pxref{Handlers,,, dico, GNU Dico Manual}).
24157 @item @code{complex?} (default: @var{#f})
24158 Whether the database configuration complex. The complex configuration
24159 will need a corresponding @code{<dicod-handler>} object, otherwise not.
24161 @item @code{options}
24162 List of strings or gexps representing the arguments for the database
24163 (@pxref{Databases,,, dico, GNU Dico Manual}).
24167 @defvr {Scheme Variable} %dicod-database:gcide
24168 A @code{<dicod-database>} object serving the GNU Collaborative International
24169 Dictionary of English using the @code{gcide} package.
24172 The following is an example @code{dicod-service} configuration.
24175 (dicod-service #:config
24176 (dicod-configuration
24177 (handlers (list (dicod-handler
24181 (list #~(string-append "dbdir=" #$wordnet))))))
24182 (databases (list (dicod-database
24185 (handler "wordnet")
24186 (options '("database=wn")))
24187 %dicod-database:gcide))))
24191 @subsubheading Docker Service
24193 The @code{(gnu services docker)} module provides the following services.
24195 @defvr {Scheme Variable} docker-service-type
24197 This is the type of the service that runs @url{https://www.docker.com,Docker},
24198 a daemon that can execute application bundles (sometimes referred to as
24199 ``containers'') in isolated environments.
24203 @deftp {Data Type} docker-configuration
24204 This is the data type representing the configuration of Docker and Containerd.
24208 @item @code{package} (default: @code{docker})
24209 The Docker package to use.
24211 @item @code{containerd} (default: @var{containerd})
24212 The Containerd package to use.
24218 @subsubheading Auditd Service
24220 The @code{(gnu services auditd)} module provides the following service.
24222 @defvr {Scheme Variable} auditd-service-type
24224 This is the type of the service that runs
24225 @url{https://people.redhat.com/sgrubb/audit/,auditd},
24226 a daemon that tracks security-relevant information on your system.
24228 Examples of things that can be tracked:
24238 Failed login attempts
24245 @command{auditctl} from the @code{audit} package can be used in order
24246 to add or remove events to be tracked (until the next reboot).
24247 In order to permanently track events, put the command line arguments
24248 of auditctl into @file{/etc/audit/audit.rules}.
24249 @command{aureport} from the @code{audit} package can be used in order
24250 to view a report of all recorded events.
24251 The audit daemon usually logs into the directory @file{/var/log/audit}.
24255 @deftp {Data Type} auditd-configuration
24256 This is the data type representing the configuration of auditd.
24260 @item @code{audit} (default: @code{audit})
24261 The audit package to use.
24266 @defvr {Scheme Variable} singularity-service-type
24267 This is the type of the service that allows you to run
24268 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
24269 create and run application bundles (aka. ``containers''). The value for this
24270 service is the Singularity package to use.
24272 The service does not install a daemon; instead, it installs helper programs as
24273 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
24274 @command{singularity run} and similar commands.
24278 @subsubheading Nix service
24280 The @code{(gnu services nix)} module provides the following service.
24282 @defvr {Scheme Variable} nix-service-type
24284 This is the type of the service that runs build daemon of the
24285 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
24289 (use-modules (gnu))
24290 (use-service-modules nix)
24291 (use-package-modules package-management)
24295 (packages (append (list nix)
24298 (services (append (list (service nix-service-type))
24302 After @command{guix system reconfigure} configure Nix for your user:
24305 @item Add a Nix channel and update it. See
24306 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
24308 @item Create a symlink to your profile and activate Nix profile:
24312 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
24313 $ source /run/current-system/profile/etc/profile.d/nix.sh
24318 @node Setuid Programs
24319 @section Setuid Programs
24321 @cindex setuid programs
24322 Some programs need to run with ``root'' privileges, even when they are
24323 launched by unprivileged users. A notorious example is the
24324 @command{passwd} program, which users can run to change their
24325 password, and which needs to access the @file{/etc/passwd} and
24326 @file{/etc/shadow} files---something normally restricted to root, for
24327 obvious security reasons. To address that, these executables are
24328 @dfn{setuid-root}, meaning that they always run with root privileges
24329 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
24330 for more info about the setuid mechanism.)
24332 The store itself @emph{cannot} contain setuid programs: that would be a
24333 security issue since any user on the system can write derivations that
24334 populate the store (@pxref{The Store}). Thus, a different mechanism is
24335 used: instead of changing the setuid bit directly on files that are in
24336 the store, we let the system administrator @emph{declare} which programs
24337 should be setuid root.
24339 The @code{setuid-programs} field of an @code{operating-system}
24340 declaration contains a list of G-expressions denoting the names of
24341 programs to be setuid-root (@pxref{Using the Configuration System}).
24342 For instance, the @command{passwd} program, which is part of the Shadow
24343 package, can be designated by this G-expression (@pxref{G-Expressions}):
24346 #~(string-append #$shadow "/bin/passwd")
24349 A default set of setuid programs is defined by the
24350 @code{%setuid-programs} variable of the @code{(gnu system)} module.
24352 @defvr {Scheme Variable} %setuid-programs
24353 A list of G-expressions denoting common programs that are setuid-root.
24355 The list includes commands such as @command{passwd}, @command{ping},
24356 @command{su}, and @command{sudo}.
24359 Under the hood, the actual setuid programs are created in the
24360 @file{/run/setuid-programs} directory at system activation time. The
24361 files in this directory refer to the ``real'' binaries, which are in the
24364 @node X.509 Certificates
24365 @section X.509 Certificates
24367 @cindex HTTPS, certificates
24368 @cindex X.509 certificates
24370 Web servers available over HTTPS (that is, HTTP over the transport-layer
24371 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
24372 that the client can then use to @emph{authenticate} the server. To do
24373 that, clients verify that the server's certificate is signed by a
24374 so-called @dfn{certificate authority} (CA). But to verify the CA's
24375 signature, clients must have first acquired the CA's certificate.
24377 Web browsers such as GNU@tie{}IceCat include their own set of CA
24378 certificates, such that they are able to verify CA signatures
24381 However, most other programs that can talk HTTPS---@command{wget},
24382 @command{git}, @command{w3m}, etc.---need to be told where CA
24383 certificates can be found.
24385 @cindex @code{nss-certs}
24386 In Guix, this is done by adding a package that provides certificates
24387 to the @code{packages} field of the @code{operating-system} declaration
24388 (@pxref{operating-system Reference}). Guix includes one such package,
24389 @code{nss-certs}, which is a set of CA certificates provided as part of
24390 Mozilla's Network Security Services.
24392 Note that it is @emph{not} part of @code{%base-packages}, so you need to
24393 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
24394 most applications and libraries look for certificates by default, points
24395 to the certificates installed globally.
24397 Unprivileged users, including users of Guix on a foreign distro,
24398 can also install their own certificate package in
24399 their profile. A number of environment variables need to be defined so
24400 that applications and libraries know where to find them. Namely, the
24401 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
24402 variables. Some applications add their own environment variables; for
24403 instance, the Git version control system honors the certificate bundle
24404 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
24405 would typically run something like:
24408 $ guix install nss-certs
24409 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
24410 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24411 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
24414 As another example, R requires the @code{CURL_CA_BUNDLE} environment
24415 variable to point to a certificate bundle, so you would have to run
24416 something like this:
24419 $ guix install nss-certs
24420 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
24423 For other applications you may want to look up the required environment
24424 variable in the relevant documentation.
24427 @node Name Service Switch
24428 @section Name Service Switch
24430 @cindex name service switch
24432 The @code{(gnu system nss)} module provides bindings to the
24433 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
24434 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
24435 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
24436 extended with new ``name'' lookup methods for system databases, which
24437 includes host names, service names, user accounts, and more (@pxref{Name
24438 Service Switch, System Databases and Name Service Switch,, libc, The GNU
24439 C Library Reference Manual}).
24441 The NSS configuration specifies, for each system database, which lookup
24442 method is to be used, and how the various methods are chained
24443 together---for instance, under which circumstances NSS should try the
24444 next method in the list. The NSS configuration is given in the
24445 @code{name-service-switch} field of @code{operating-system} declarations
24446 (@pxref{operating-system Reference, @code{name-service-switch}}).
24449 @cindex .local, host name lookup
24450 As an example, the declaration below configures the NSS to use the
24451 @uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
24452 back-end}, which supports host name lookups over multicast DNS (mDNS)
24453 for host names ending in @code{.local}:
24456 (name-service-switch
24457 (hosts (list %files ;first, check /etc/hosts
24459 ;; If the above did not succeed, try
24460 ;; with 'mdns_minimal'.
24462 (name "mdns_minimal")
24464 ;; 'mdns_minimal' is authoritative for
24465 ;; '.local'. When it returns "not found",
24466 ;; no need to try the next methods.
24467 (reaction (lookup-specification
24468 (not-found => return))))
24470 ;; Then fall back to DNS.
24474 ;; Finally, try with the "full" 'mdns'.
24479 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
24480 contains this configuration, so you will not have to type it if all you
24481 want is to have @code{.local} host lookup working.
24483 Note that, in this case, in addition to setting the
24484 @code{name-service-switch} of the @code{operating-system} declaration,
24485 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
24486 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
24487 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
24488 to the name service cache daemon (@pxref{Base Services,
24489 @code{nscd-service}}).
24491 For convenience, the following variables provide typical NSS
24494 @defvr {Scheme Variable} %default-nss
24495 This is the default name service switch configuration, a
24496 @code{name-service-switch} object.
24499 @defvr {Scheme Variable} %mdns-host-lookup-nss
24500 This is the name service switch configuration with support for host name
24501 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
24504 The reference for name service switch configuration is given below. It
24505 is a direct mapping of the configuration file format of the C library , so
24506 please refer to the C library manual for more information (@pxref{NSS
24507 Configuration File,,, libc, The GNU C Library Reference Manual}).
24508 Compared to the configuration file format of libc NSS, it has the advantage
24509 not only of adding this warm parenthetic feel that we like, but also
24510 static checks: you will know about syntax errors and typos as soon as you
24511 run @command{guix system}.
24513 @deftp {Data Type} name-service-switch
24515 This is the data type representation the configuration of libc's name
24516 service switch (NSS). Each field below represents one of the supported
24533 The system databases handled by the NSS. Each of these fields must be a
24534 list of @code{<name-service>} objects (see below).
24538 @deftp {Data Type} name-service
24540 This is the data type representing an actual name service and the
24541 associated lookup action.
24545 A string denoting the name service (@pxref{Services in the NSS
24546 configuration,,, libc, The GNU C Library Reference Manual}).
24548 Note that name services listed here must be visible to nscd. This is
24549 achieved by passing the @code{#:name-services} argument to
24550 @code{nscd-service} the list of packages providing the needed name
24551 services (@pxref{Base Services, @code{nscd-service}}).
24554 An action specified using the @code{lookup-specification} macro
24555 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
24556 Reference Manual}). For example:
24559 (lookup-specification (unavailable => continue)
24560 (success => return))
24565 @node Initial RAM Disk
24566 @section Initial RAM Disk
24569 @cindex initial RAM disk
24570 For bootstrapping purposes, the Linux-Libre kernel is passed an
24571 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
24572 root file system as well as an initialization script. The latter is
24573 responsible for mounting the real root file system, and for loading any
24574 kernel modules that may be needed to achieve that.
24576 The @code{initrd-modules} field of an @code{operating-system}
24577 declaration allows you to specify Linux-libre kernel modules that must
24578 be available in the initrd. In particular, this is where you would list
24579 modules needed to actually drive the hard disk where your root partition
24580 is---although the default value of @code{initrd-modules} should cover
24581 most use cases. For example, assuming you need the @code{megaraid_sas}
24582 module in addition to the default modules to be able to access your root
24583 file system, you would write:
24588 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
24591 @defvr {Scheme Variable} %base-initrd-modules
24592 This is the list of kernel modules included in the initrd by default.
24595 Furthermore, if you need lower-level customization, the @code{initrd}
24596 field of an @code{operating-system} declaration allows
24597 you to specify which initrd you would like to use. The @code{(gnu
24598 system linux-initrd)} module provides three ways to build an initrd: the
24599 high-level @code{base-initrd} procedure and the low-level
24600 @code{raw-initrd} and @code{expression->initrd} procedures.
24602 The @code{base-initrd} procedure is intended to cover most common uses.
24603 For example, if you want to add a bunch of kernel modules to be loaded
24604 at boot time, you can define the @code{initrd} field of the operating
24605 system declaration like this:
24608 (initrd (lambda (file-systems . rest)
24609 ;; Create a standard initrd but set up networking
24610 ;; with the parameters QEMU expects by default.
24611 (apply base-initrd file-systems
24612 #:qemu-networking? #t
24616 The @code{base-initrd} procedure also handles common use cases that
24617 involves using the system as a QEMU guest, or as a ``live'' system with
24618 volatile root file system.
24620 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
24621 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
24622 such as trying to guess which kernel modules and packages should be included
24623 to the initrd. An example use of @code{raw-initrd} is when a user has
24624 a custom Linux kernel configuration and default kernel modules included by
24625 @code{base-initrd} are not available.
24627 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
24628 honors several options passed on the Linux kernel command line
24629 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
24630 @code{-append} option of QEMU), notably:
24633 @item --load=@var{boot}
24634 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
24635 program, once it has mounted the root file system.
24637 Guix uses this option to yield control to a boot program that runs the
24638 service activation programs and then spawns the GNU@tie{}Shepherd, the
24639 initialization system.
24641 @item --root=@var{root}
24642 Mount @var{root} as the root file system. @var{root} can be a
24643 device name like @code{/dev/sda1}, a file system label, or a file system
24646 @item --system=@var{system}
24647 Have @file{/run/booted-system} and @file{/run/current-system} point to
24650 @item modprobe.blacklist=@var{modules}@dots{}
24651 @cindex module, black-listing
24652 @cindex black list, of kernel modules
24653 Instruct the initial RAM disk as well as the @command{modprobe} command
24654 (from the kmod package) to refuse to load @var{modules}. @var{modules}
24655 must be a comma-separated list of module names---e.g.,
24656 @code{usbkbd,9pnet}.
24659 Start a read-eval-print loop (REPL) from the initial RAM disk before it
24660 tries to load kernel modules and to mount the root file system. Our
24661 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
24662 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
24663 Manual}, for more information on Guile's REPL.
24667 Now that you know all the features that initial RAM disks produced by
24668 @code{base-initrd} and @code{raw-initrd} provide,
24669 here is how to use it and customize it further.
24672 @cindex initial RAM disk
24673 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
24674 [#:linux-modules '()] [#:mapped-devices '()] @
24675 [#:keyboard-layout #f] @
24676 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
24677 Return a derivation that builds a raw initrd. @var{file-systems} is
24678 a list of file systems to be mounted by the initrd, possibly in addition to
24679 the root file system specified on the kernel command line via @code{--root}.
24680 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
24681 @var{mapped-devices} is a list of device mappings to realize before
24682 @var{file-systems} are mounted (@pxref{Mapped Devices}).
24683 @var{helper-packages} is a list of packages to be copied in the initrd. It may
24684 include @code{e2fsck/static} or other packages needed by the initrd to check
24685 the root file system.
24687 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24688 the desired console keyboard layout. This is done before @var{mapped-devices}
24689 are set up and before @var{file-systems} are mounted such that, should the
24690 user need to enter a passphrase or use the REPL, this happens using the
24691 intended keyboard layout.
24693 When @var{qemu-networking?} is true, set up networking with the standard QEMU
24694 parameters. When @var{virtio?} is true, load additional modules so that the
24695 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
24697 When @var{volatile-root?} is true, the root file system is writable but any changes
24701 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
24702 [#:mapped-devices '()] [#:keyboard-layout #f] @
24703 [#:qemu-networking? #f] [#:volatile-root? #f] @
24704 [#:linux-modules '()]
24705 Return as a file-like object a generic initrd, with kernel
24706 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
24707 mounted by the initrd, possibly in addition to the root file system specified
24708 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
24709 mappings to realize before @var{file-systems} are mounted.
24711 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
24712 the desired console keyboard layout. This is done before @var{mapped-devices}
24713 are set up and before @var{file-systems} are mounted such that, should the
24714 user need to enter a passphrase or use the REPL, this happens using the
24715 intended keyboard layout.
24717 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
24719 The initrd is automatically populated with all the kernel modules necessary
24720 for @var{file-systems} and for the given options. Additional kernel
24721 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
24722 loaded at boot time in the order in which they appear.
24725 Needless to say, the initrds we produce and use embed a
24726 statically-linked Guile, and the initialization program is a Guile
24727 program. That gives a lot of flexibility. The
24728 @code{expression->initrd} procedure builds such an initrd, given the
24729 program to run in that initrd.
24731 @deffn {Scheme Procedure} expression->initrd @var{exp} @
24732 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
24733 Return as a file-like object a Linux initrd (a gzipped cpio archive)
24734 containing @var{guile} and that evaluates @var{exp}, a G-expression,
24735 upon booting. All the derivations referenced by @var{exp} are
24736 automatically copied to the initrd.
24739 @node Bootloader Configuration
24740 @section Bootloader Configuration
24743 @cindex boot loader
24745 The operating system supports multiple bootloaders. The bootloader is
24746 configured using @code{bootloader-configuration} declaration. All the
24747 fields of this structure are bootloader agnostic except for one field,
24748 @code{bootloader} that indicates the bootloader to be configured and
24751 Some of the bootloaders do not honor every field of
24752 @code{bootloader-configuration}. For instance, the extlinux
24753 bootloader does not support themes and thus ignores the @code{theme}
24756 @deftp {Data Type} bootloader-configuration
24757 The type of a bootloader configuration declaration.
24761 @item @code{bootloader}
24762 @cindex EFI, bootloader
24763 @cindex UEFI, bootloader
24764 @cindex BIOS, bootloader
24765 The bootloader to use, as a @code{bootloader} object. For now
24766 @code{grub-bootloader}, @code{grub-efi-bootloader},
24767 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
24769 @vindex grub-efi-bootloader
24770 @code{grub-efi-bootloader} allows to boot on modern systems using the
24771 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
24772 use if the installation image contains a @file{/sys/firmware/efi} directory
24773 when you boot it on your system.
24775 @vindex grub-bootloader
24776 @code{grub-bootloader} allows you to boot in particular Intel-based machines
24777 in ``legacy'' BIOS mode.
24779 @cindex ARM, bootloaders
24780 @cindex AArch64, bootloaders
24781 Available bootloaders are described in @code{(gnu bootloader @dots{})}
24782 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
24783 of bootloaders for a wide range of ARM and AArch64 systems, using the
24784 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
24786 @item @code{target}
24787 This is a string denoting the target onto which to install the
24790 The interpretation depends on the bootloader in question. For
24791 @code{grub-bootloader}, for example, it should be a device name understood by
24792 the bootloader @command{installer} command, such as @code{/dev/sda} or
24793 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
24794 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
24795 system, usually @file{/boot/efi}.
24797 @item @code{menu-entries} (default: @code{()})
24798 A possibly empty list of @code{menu-entry} objects (see below), denoting
24799 entries to appear in the bootloader menu, in addition to the current
24800 system entry and the entry pointing to previous system generations.
24802 @item @code{default-entry} (default: @code{0})
24803 The index of the default boot menu entry. Index 0 is for the entry of the
24806 @item @code{timeout} (default: @code{5})
24807 The number of seconds to wait for keyboard input before booting. Set to
24808 0 to boot immediately, and to -1 to wait indefinitely.
24810 @cindex keyboard layout, for the bootloader
24811 @item @code{keyboard-layout} (default: @code{#f})
24812 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
24813 layout, usually US@tie{}English (``qwerty'').
24815 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
24819 This option is currently ignored by bootloaders other than @code{grub} and
24823 @item @code{theme} (default: @var{#f})
24824 The bootloader theme object describing the theme to use. If no theme
24825 is provided, some bootloaders might use a default theme, that's true
24828 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
24829 The output terminals used for the bootloader boot menu, as a list of
24830 symbols. GRUB accepts the values: @code{console}, @code{serial},
24831 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
24832 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
24833 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
24834 configuration,,, grub,GNU GRUB manual}).
24836 @item @code{terminal-inputs} (default: @code{'()})
24837 The input terminals used for the bootloader boot menu, as a list of
24838 symbols. For GRUB, the default is the native platform terminal as
24839 determined at run-time. GRUB accepts the values: @code{console},
24840 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
24841 @code{usb_keyboard}. This field corresponds to the GRUB variable
24842 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
24845 @item @code{serial-unit} (default: @code{#f})
24846 The serial unit used by the bootloader, as an integer from 0 to 3.
24847 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
24848 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
24850 @item @code{serial-speed} (default: @code{#f})
24851 The speed of the serial interface, as an integer. For GRUB, the
24852 default value is chosen at run-time; currently GRUB chooses
24853 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
24860 Should you want to list additional boot menu entries @i{via} the
24861 @code{menu-entries} field above, you will need to create them with the
24862 @code{menu-entry} form. For example, imagine you want to be able to
24863 boot another distro (hard to imagine!), you can define a menu entry
24868 (label "The Other Distro")
24869 (linux "/boot/old/vmlinux-2.6.32")
24870 (linux-arguments '("root=/dev/sda2"))
24871 (initrd "/boot/old/initrd"))
24876 @deftp {Data Type} menu-entry
24877 The type of an entry in the bootloader menu.
24882 The label to show in the menu---e.g., @code{"GNU"}.
24885 The Linux kernel image to boot, for example:
24888 (file-append linux-libre "/bzImage")
24891 For GRUB, it is also possible to specify a device explicitly in the
24892 file path using GRUB's device naming convention (@pxref{Naming
24893 convention,,, grub, GNU GRUB manual}), for example:
24896 "(hd0,msdos1)/boot/vmlinuz"
24899 If the device is specified explicitly as above, then the @code{device}
24900 field is ignored entirely.
24902 @item @code{linux-arguments} (default: @code{()})
24903 The list of extra Linux kernel command-line arguments---e.g.,
24904 @code{("console=ttyS0")}.
24906 @item @code{initrd}
24907 A G-Expression or string denoting the file name of the initial RAM disk
24908 to use (@pxref{G-Expressions}).
24909 @item @code{device} (default: @code{#f})
24910 The device where the kernel and initrd are to be found---i.e., for GRUB,
24911 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
24913 This may be a file system label (a string), a file system UUID (a
24914 bytevector, @pxref{File Systems}), or @code{#f}, in which case
24915 the bootloader will search the device containing the file specified by
24916 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
24917 must @emph{not} be an OS device name such as @file{/dev/sda1}.
24922 @c FIXME: Write documentation once it's stable.
24923 For now only GRUB has theme support. GRUB themes are created using
24924 the @code{grub-theme} form, which is not documented yet.
24926 @defvr {Scheme Variable} %default-theme
24927 This is the default GRUB theme used by the operating system if no
24928 @code{theme} field is specified in @code{bootloader-configuration}
24931 It comes with a fancy background image displaying the GNU and Guix
24936 @node Invoking guix system
24937 @section Invoking @code{guix system}
24939 Once you have written an operating system declaration as seen in the
24940 previous section, it can be @dfn{instantiated} using the @command{guix
24941 system} command. The synopsis is:
24944 guix system @var{options}@dots{} @var{action} @var{file}
24947 @var{file} must be the name of a file containing an
24948 @code{operating-system} declaration. @var{action} specifies how the
24949 operating system is instantiated. Currently the following values are
24954 Display available service type definitions that match the given regular
24955 expressions, sorted by relevance:
24958 $ guix system search console font
24959 name: console-fonts
24960 location: gnu/services/base.scm:729:2
24961 extends: shepherd-root
24962 description: Install the given fonts on the specified ttys (fonts are
24963 + per virtual console on GNU/Linux). The value of this service is a list
24964 + of tty/font pairs like:
24966 + '(("tty1" . "LatGrkCyr-8x16"))
24970 location: gnu/services/base.scm:1048:2
24971 extends: shepherd-root
24972 description: Provide console login using the `mingetty' program.
24976 location: gnu/services/base.scm:775:2
24978 description: Provide a console log-in service as specified by its
24979 + configuration value, a `login-configuration' object.
24985 As for @command{guix package --search}, the result is written in
24986 @code{recutils} format, which makes it easy to filter the output
24987 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
24990 Build the operating system described in @var{file}, activate it, and
24991 switch to it@footnote{This action (and the related actions
24992 @code{switch-generation} and @code{roll-back}) are usable only on
24993 systems already running Guix System.}.
24995 This effects all the configuration specified in @var{file}: user
24996 accounts, system services, global package list, setuid programs, etc.
24997 The command starts system services specified in @var{file} that are not
24998 currently running; if a service is currently running this command will
24999 arrange for it to be upgraded the next time it is stopped (e.g.@: by
25000 @code{herd stop X} or @code{herd restart X}).
25002 This command creates a new generation whose number is one greater than
25003 the current generation (as reported by @command{guix system
25004 list-generations}). If that generation already exists, it will be
25005 overwritten. This behavior mirrors that of @command{guix package}
25006 (@pxref{Invoking guix package}).
25008 It also adds a bootloader menu entry for the new OS configuration,
25009 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
25010 entries for older configurations to a submenu, allowing you to choose
25011 an older system generation at boot time should you need it.
25014 @c The paragraph below refers to the problem discussed at
25015 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
25016 It is highly recommended to run @command{guix pull} once before you run
25017 @command{guix system reconfigure} for the first time (@pxref{Invoking
25018 guix pull}). Failing to do that you would see an older version of Guix
25019 once @command{reconfigure} has completed.
25022 @item switch-generation
25023 @cindex generations
25024 Switch to an existing system generation. This action atomically
25025 switches the system profile to the specified system generation. It
25026 also rearranges the system's existing bootloader menu entries. It
25027 makes the menu entry for the specified system generation the default,
25028 and it moves the entries for the other generatiors to a submenu, if
25029 supported by the bootloader being used. The next time the system
25030 boots, it will use the specified system generation.
25032 The bootloader itself is not being reinstalled when using this
25033 command. Thus, the installed bootloader is used with an updated
25034 configuration file.
25036 The target generation can be specified explicitly by its generation
25037 number. For example, the following invocation would switch to system
25041 guix system switch-generation 7
25044 The target generation can also be specified relative to the current
25045 generation with the form @code{+N} or @code{-N}, where @code{+3} means
25046 ``3 generations ahead of the current generation,'' and @code{-1} means
25047 ``1 generation prior to the current generation.'' When specifying a
25048 negative value such as @code{-1}, you must precede it with @code{--} to
25049 prevent it from being parsed as an option. For example:
25052 guix system switch-generation -- -1
25055 Currently, the effect of invoking this action is @emph{only} to switch
25056 the system profile to an existing generation and rearrange the
25057 bootloader menu entries. To actually start using the target system
25058 generation, you must reboot after running this action. In the future,
25059 it will be updated to do the same things as @command{reconfigure},
25060 like activating and deactivating services.
25062 This action will fail if the specified generation does not exist.
25065 @cindex rolling back
25066 Switch to the preceding system generation. The next time the system
25067 boots, it will use the preceding system generation. This is the inverse
25068 of @command{reconfigure}, and it is exactly the same as invoking
25069 @command{switch-generation} with an argument of @code{-1}.
25071 Currently, as with @command{switch-generation}, you must reboot after
25072 running this action to actually start using the preceding system
25075 @item delete-generations
25076 @cindex deleting system generations
25077 @cindex saving space
25078 Delete system generations, making them candidates for garbage collection
25079 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
25082 This works in the same way as @command{guix package --delete-generations}
25083 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
25084 arguments, all system generations but the current one are deleted:
25087 guix system delete-generations
25090 You can also select the generations you want to delete. The example below
25091 deletes all the system generations that are more than two month old:
25094 guix system delete-generations 2m
25097 Running this command automatically reinstalls the bootloader with an updated
25098 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
25099 longer lists the generations that have been deleted.
25102 Build the derivation of the operating system, which includes all the
25103 configuration files and programs needed to boot and run the system.
25104 This action does not actually install anything.
25107 Populate the given directory with all the files necessary to run the
25108 operating system specified in @var{file}. This is useful for first-time
25109 installations of Guix System. For instance:
25112 guix system init my-os-config.scm /mnt
25115 copies to @file{/mnt} all the store items required by the configuration
25116 specified in @file{my-os-config.scm}. This includes configuration
25117 files, packages, and so on. It also creates other essential files
25118 needed for the system to operate correctly---e.g., the @file{/etc},
25119 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
25121 This command also installs bootloader on the target specified in
25122 @file{my-os-config}, unless the @option{--no-bootloader} option was
25126 @cindex virtual machine
25128 @anchor{guix system vm}
25129 Build a virtual machine that contains the operating system declared in
25130 @var{file}, and return a script to run that virtual machine (VM).
25133 The @code{vm} action and others below
25134 can use KVM support in the Linux-libre kernel. Specifically, if the
25135 machine has hardware virtualization support, the corresponding
25136 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
25137 must exist and be readable and writable by the user and by the
25138 build users of the daemon (@pxref{Build Environment Setup}).
25141 Arguments given to the script are passed to QEMU as in the example
25142 below, which enables networking and requests 1@tie{}GiB of RAM for the
25146 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -net user
25149 The VM shares its store with the host system.
25151 Additional file systems can be shared between the host and the VM using
25152 the @code{--share} and @code{--expose} command-line options: the former
25153 specifies a directory to be shared with write access, while the latter
25154 provides read-only access to the shared directory.
25156 The example below creates a VM in which the user's home directory is
25157 accessible read-only, and where the @file{/exchange} directory is a
25158 read-write mapping of @file{$HOME/tmp} on the host:
25161 guix system vm my-config.scm \
25162 --expose=$HOME --share=$HOME/tmp=/exchange
25165 On GNU/Linux, the default is to boot directly to the kernel; this has
25166 the advantage of requiring only a very tiny root disk image since the
25167 store of the host can then be mounted.
25169 The @code{--full-boot} option forces a complete boot sequence, starting
25170 with the bootloader. This requires more disk space since a root image
25171 containing at least the kernel, initrd, and bootloader data files must
25172 be created. The @code{--image-size} option can be used to specify the
25175 @cindex System images, creation in various formats
25176 @cindex Creating system images in various formats
25179 @itemx docker-image
25180 Return a virtual machine, disk image, or Docker image of the operating
25181 system declared in @var{file} that stands alone. By default,
25182 @command{guix system} estimates the size of the image needed to store
25183 the system, but you can use the @option{--image-size} option to specify
25184 a value. Docker images are built to contain exactly what they need, so
25185 the @option{--image-size} option is ignored in the case of
25186 @code{docker-image}.
25188 You can specify the root file system type by using the
25189 @option{--file-system-type} option. It defaults to @code{ext4}.
25191 When using @code{vm-image}, the returned image is in qcow2 format, which
25192 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
25193 for more information on how to run the image in a virtual machine.
25195 When using @code{disk-image}, a raw disk image is produced; it can be
25196 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
25197 the device corresponding to a USB stick, one can copy the image to it
25198 using the following command:
25201 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
25204 When using @code{docker-image}, a Docker image is produced. Guix builds
25205 the image from scratch, not from a pre-existing Docker base image. As a
25206 result, it contains @emph{exactly} what you define in the operating
25207 system configuration file. You can then load the image and launch a
25208 Docker container using commands like the following:
25211 image_id="`docker load < guix-system-docker-image.tar.gz`"
25212 container_id="`docker create $image_id`"
25213 docker start $container_id
25216 This command starts a new Docker container from the specified image. It
25217 will boot the Guix system in the usual manner, which means it will
25218 start any services you have defined in the operating system
25219 configuration. You can get an interactive shell running in the container
25220 using @command{docker exec}:
25223 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
25226 Depending on what you run in the Docker container, it
25227 may be necessary to give the container additional permissions. For
25228 example, if you intend to build software using Guix inside of the Docker
25229 container, you may need to pass the @option{--privileged} option to
25230 @code{docker create}.
25233 Return a script to run the operating system declared in @var{file}
25234 within a container. Containers are a set of lightweight isolation
25235 mechanisms provided by the kernel Linux-libre. Containers are
25236 substantially less resource-demanding than full virtual machines since
25237 the kernel, shared objects, and other resources can be shared with the
25238 host system; this also means they provide thinner isolation.
25240 Currently, the script must be run as root in order to support more than
25241 a single user and group. The container shares its store with the host
25244 As with the @code{vm} action (@pxref{guix system vm}), additional file
25245 systems to be shared between the host and container can be specified
25246 using the @option{--share} and @option{--expose} options:
25249 guix system container my-config.scm \
25250 --expose=$HOME --share=$HOME/tmp=/exchange
25254 This option requires Linux-libre 3.19 or newer.
25259 @var{options} can contain any of the common build options (@pxref{Common
25260 Build Options}). In addition, @var{options} can contain one of the
25264 @item --expression=@var{expr}
25265 @itemx -e @var{expr}
25266 Consider the operating-system @var{expr} evaluates to.
25267 This is an alternative to specifying a file which evaluates to an
25269 This is used to generate the Guix system installer @pxref{Building the
25270 Installation Image}).
25272 @item --system=@var{system}
25273 @itemx -s @var{system}
25274 Attempt to build for @var{system} instead of the host system type.
25275 This works as per @command{guix build} (@pxref{Invoking guix build}).
25279 Return the derivation file name of the given operating system without
25282 @item --file-system-type=@var{type}
25283 @itemx -t @var{type}
25284 For the @code{disk-image} action, create a file system of the given
25285 @var{type} on the image.
25287 When this option is omitted, @command{guix system} uses @code{ext4}.
25289 @cindex ISO-9660 format
25290 @cindex CD image format
25291 @cindex DVD image format
25292 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
25293 for burning on CDs and DVDs.
25295 @item --image-size=@var{size}
25296 For the @code{vm-image} and @code{disk-image} actions, create an image
25297 of the given @var{size}. @var{size} may be a number of bytes, or it may
25298 include a unit as a suffix (@pxref{Block size, size specifications,,
25299 coreutils, GNU Coreutils}).
25301 When this option is omitted, @command{guix system} computes an estimate
25302 of the image size as a function of the size of the system declared in
25307 For the @code{container} action, allow containers to access the host network,
25308 that is, do not create a network namespace.
25310 @item --root=@var{file}
25311 @itemx -r @var{file}
25312 Make @var{file} a symlink to the result, and register it as a garbage
25315 @item --skip-checks
25316 Skip pre-installation safety checks.
25318 By default, @command{guix system init} and @command{guix system
25319 reconfigure} perform safety checks: they make sure the file systems that
25320 appear in the @code{operating-system} declaration actually exist
25321 (@pxref{File Systems}), and that any Linux kernel modules that may be
25322 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
25323 RAM Disk}). Passing this option skips these tests altogether.
25326 @cindex on-error strategy
25327 @cindex error strategy
25328 @item --on-error=@var{strategy}
25329 Apply @var{strategy} when an error occurs when reading @var{file}.
25330 @var{strategy} may be one of the following:
25333 @item nothing-special
25334 Report the error concisely and exit. This is the default strategy.
25337 Likewise, but also display a backtrace.
25340 Report the error and enter Guile's debugger. From there, you can run
25341 commands such as @code{,bt} to get a backtrace, @code{,locals} to
25342 display local variable values, and more generally inspect the state of the
25343 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
25344 a list of available debugging commands.
25348 Once you have built, configured, re-configured, and re-re-configured
25349 your Guix installation, you may find it useful to list the operating
25350 system generations available on disk---and that you can choose from the
25351 bootloader boot menu:
25355 @item list-generations
25356 List a summary of each generation of the operating system available on
25357 disk, in a human-readable way. This is similar to the
25358 @option{--list-generations} option of @command{guix package}
25359 (@pxref{Invoking guix package}).
25361 Optionally, one can specify a pattern, with the same syntax that is used
25362 in @command{guix package --list-generations}, to restrict the list of
25363 generations displayed. For instance, the following command displays
25364 generations that are up to 10 days old:
25367 $ guix system list-generations 10d
25372 The @command{guix system} command has even more to offer! The following
25373 sub-commands allow you to visualize how your system services relate to
25376 @anchor{system-extension-graph}
25379 @item extension-graph
25380 Emit in Dot/Graphviz format to standard output the @dfn{service
25381 extension graph} of the operating system defined in @var{file}
25382 (@pxref{Service Composition}, for more information on service
25388 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
25391 produces a PDF file showing the extension relations among services.
25393 @anchor{system-shepherd-graph}
25394 @item shepherd-graph
25395 Emit in Dot/Graphviz format to standard output the @dfn{dependency
25396 graph} of shepherd services of the operating system defined in
25397 @var{file}. @xref{Shepherd Services}, for more information and for an
25402 @node Running Guix in a VM
25403 @section Running Guix in a Virtual Machine
25405 @cindex virtual machine
25406 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
25408 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
25409 This image is a compressed image in QCOW format. You will first need to
25410 decompress with @command{xz -d}, and then you can pass it to an emulator such
25411 as QEMU (see below for details).
25413 This image boots the Xfce graphical environment and it contains some
25414 commonly-used tools. You can install more software in the image by running
25415 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
25416 also reconfigure the system based on its initial configuration file available
25417 as @file{/etc/config.scm} (@pxref{Using the Configuration System}).
25419 Instead of using this pre-built image, one can also build their own virtual
25420 machine image using @command{guix system vm-image} (@pxref{Invoking guix
25421 system}). The returned image is in qcow2 format, which the
25422 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
25425 If you built your own image, you must copy it out of the store
25426 (@pxref{The Store}) and give yourself permission to write to the copy
25427 before you can use it. When invoking QEMU, you must choose a system
25428 emulator that is suitable for your hardware platform. Here is a minimal
25429 QEMU invocation that will boot the result of @command{guix system
25430 vm-image} on x86_64 hardware:
25433 $ qemu-system-x86_64 \
25434 -net user -net nic,model=virtio \
25435 -enable-kvm -m 512 \
25436 -device virtio-blk,drive=myhd \
25437 -drive if=none,file=/tmp/qemu-image,id=myhd
25440 Here is what each of these options means:
25443 @item qemu-system-x86_64
25444 This specifies the hardware platform to emulate. This should match the
25448 Enable the unprivileged user-mode network stack. The guest OS can
25449 access the host but not vice versa. This is the simplest way to get the
25452 @item -net nic,model=virtio
25453 You must create a network interface of a given model. If you do not
25454 create a NIC, the boot will fail. Assuming your hardware platform is
25455 x86_64, you can get a list of available NIC models by running
25456 @command{qemu-system-x86_64 -net nic,model=help}.
25459 If your system has hardware virtualization extensions, enabling the
25460 virtual machine support (KVM) of the Linux kernel will make things run
25463 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
25465 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
25466 which may be insufficient for some operations.
25468 @item -device virtio-blk,drive=myhd
25469 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
25470 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
25471 better performance than if it were emulating a complete disk drive. See the
25472 QEMU and KVM documentation for more info.
25474 @item -drive if=none,file=/tmp/qemu-image,id=myhd
25475 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
25476 the ``myhd'' drive.
25479 The default @command{run-vm.sh} script that is returned by an invocation of
25480 @command{guix system vm} does not add a @command{-net user} flag by default.
25481 To get network access from within the vm add the @code{(dhcp-client-service)}
25482 to your system definition and start the VM using
25483 @command{`guix system vm config.scm` -net user}. An important caveat of using
25484 @command{-net user} for networking is that @command{ping} will not work, because
25485 it uses the ICMP protocol. You'll have to use a different command to check for
25486 network connectivity, for example @command{guix download}.
25488 @subsection Connecting Through SSH
25492 To enable SSH inside a VM you need to add an SSH server like
25493 @code{openssh-service-type} to your VM (@pxref{Networking Services,
25494 @code{openssh-service-type}}). In addition you need to forward the SSH port,
25495 22 by default, to the host. You can do this with
25498 `guix system vm config.scm` -net user,hostfwd=tcp::10022-:22
25501 To connect to the VM you can run
25504 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
25507 The @command{-p} tells @command{ssh} the port you want to connect to.
25508 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
25509 every time you modify your @command{config.scm} file and the
25510 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
25511 connection to an unknown host every time you connect.
25513 @subsection Using @command{virt-viewer} with Spice
25515 As an alternative to the default @command{qemu} graphical client you can
25516 use the @command{remote-viewer} from the @command{virt-viewer} package. To
25517 connect pass the @command{-spice port=5930,disable-ticketing} flag to
25518 @command{qemu}. See previous section for further information on how to do this.
25520 Spice also allows you to do some nice stuff like share your clipboard with your
25521 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
25524 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
25525 -chardev spicevmc,name=vdagent,id=vdagent
25526 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
25527 name=com.redhat.spice.0
25530 You'll also need to add the @pxref{Miscellaneous Services, Spice service}.
25532 @node Defining Services
25533 @section Defining Services
25535 The previous sections show the available services and how one can combine
25536 them in an @code{operating-system} declaration. But how do we define
25537 them in the first place? And what is a service anyway?
25540 * Service Composition:: The model for composing services.
25541 * Service Types and Services:: Types and services.
25542 * Service Reference:: API reference.
25543 * Shepherd Services:: A particular type of service.
25546 @node Service Composition
25547 @subsection Service Composition
25551 Here we define a @dfn{service} as, broadly, something that extends the
25552 functionality of the operating system. Often a service is a process---a
25553 @dfn{daemon}---started when the system boots: a secure shell server, a
25554 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
25555 whose execution can be triggered by another daemon---e.g., an FTP server
25556 started by @command{inetd} or a D-Bus service activated by
25557 @command{dbus-daemon}. Occasionally, a service does not map to a
25558 daemon. For instance, the ``account'' service collects user accounts
25559 and makes sure they exist when the system runs; the ``udev'' service
25560 collects device management rules and makes them available to the eudev
25561 daemon; the @file{/etc} service populates the @file{/etc} directory
25564 @cindex service extensions
25565 Guix system services are connected by @dfn{extensions}. For instance, the
25566 secure shell service @emph{extends} the Shepherd---the
25567 initialization system, running as PID@tie{}1---by giving it the command
25568 lines to start and stop the secure shell daemon (@pxref{Networking
25569 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
25570 service by passing it its @file{.service} specification, and extends the
25571 udev service by passing it device management rules (@pxref{Desktop
25572 Services, @code{upower-service}}); the Guix daemon service extends the
25573 Shepherd by passing it the command lines to start and stop the daemon,
25574 and extends the account service by passing it a list of required build
25575 user accounts (@pxref{Base Services}).
25577 All in all, services and their ``extends'' relations form a directed
25578 acyclic graph (DAG). If we represent services as boxes and extensions
25579 as arrows, a typical system might provide something like this:
25581 @image{images/service-graph,,5in,Typical service extension graph.}
25583 @cindex system service
25584 At the bottom, we see the @dfn{system service}, which produces the
25585 directory containing everything to run and boot the system, as returned
25586 by the @command{guix system build} command. @xref{Service Reference},
25587 to learn about the other service types shown here.
25588 @xref{system-extension-graph, the @command{guix system extension-graph}
25589 command}, for information on how to generate this representation for a
25590 particular operating system definition.
25592 @cindex service types
25593 Technically, developers can define @dfn{service types} to express these
25594 relations. There can be any number of services of a given type on the
25595 system---for instance, a system running two instances of the GNU secure
25596 shell server (lsh) has two instances of @code{lsh-service-type}, with
25597 different parameters.
25599 The following section describes the programming interface for service
25600 types and services.
25602 @node Service Types and Services
25603 @subsection Service Types and Services
25605 A @dfn{service type} is a node in the DAG described above. Let us start
25606 with a simple example, the service type for the Guix build daemon
25607 (@pxref{Invoking guix-daemon}):
25610 (define guix-service-type
25614 (list (service-extension shepherd-root-service-type guix-shepherd-service)
25615 (service-extension account-service-type guix-accounts)
25616 (service-extension activation-service-type guix-activation)))
25617 (default-value (guix-configuration))))
25621 It defines three things:
25625 A name, whose sole purpose is to make inspection and debugging easier.
25628 A list of @dfn{service extensions}, where each extension designates the
25629 target service type and a procedure that, given the parameters of the
25630 service, returns a list of objects to extend the service of that type.
25632 Every service type has at least one service extension. The only
25633 exception is the @dfn{boot service type}, which is the ultimate service.
25636 Optionally, a default value for instances of this type.
25639 In this example, @code{guix-service-type} extends three services:
25642 @item shepherd-root-service-type
25643 The @code{guix-shepherd-service} procedure defines how the Shepherd
25644 service is extended. Namely, it returns a @code{<shepherd-service>}
25645 object that defines how @command{guix-daemon} is started and stopped
25646 (@pxref{Shepherd Services}).
25648 @item account-service-type
25649 This extension for this service is computed by @code{guix-accounts},
25650 which returns a list of @code{user-group} and @code{user-account}
25651 objects representing the build user accounts (@pxref{Invoking
25654 @item activation-service-type
25655 Here @code{guix-activation} is a procedure that returns a gexp, which is
25656 a code snippet to run at ``activation time''---e.g., when the service is
25660 A service of this type is instantiated like this:
25663 (service guix-service-type
25664 (guix-configuration
25666 (use-substitutes? #f)))
25669 The second argument to the @code{service} form is a value representing
25670 the parameters of this specific service instance.
25671 @xref{guix-configuration-type, @code{guix-configuration}}, for
25672 information about the @code{guix-configuration} data type. When the
25673 value is omitted, the default value specified by
25674 @code{guix-service-type} is used:
25677 (service guix-service-type)
25680 @code{guix-service-type} is quite simple because it extends other
25681 services but is not extensible itself.
25683 @c @subsubsubsection Extensible Service Types
25685 The service type for an @emph{extensible} service looks like this:
25688 (define udev-service-type
25689 (service-type (name 'udev)
25691 (list (service-extension shepherd-root-service-type
25692 udev-shepherd-service)))
25694 (compose concatenate) ;concatenate the list of rules
25695 (extend (lambda (config rules)
25697 (($ <udev-configuration> udev initial-rules)
25698 (udev-configuration
25699 (udev udev) ;the udev package to use
25700 (rules (append initial-rules rules)))))))))
25703 This is the service type for the
25704 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
25705 management daemon}. Compared to the previous example, in addition to an
25706 extension of @code{shepherd-root-service-type}, we see two new fields:
25710 This is the procedure to @dfn{compose} the list of extensions to
25711 services of this type.
25713 Services can extend the udev service by passing it lists of rules; we
25714 compose those extensions simply by concatenating them.
25717 This procedure defines how the value of the service is @dfn{extended} with
25718 the composition of the extensions.
25720 Udev extensions are composed into a list of rules, but the udev service
25721 value is itself a @code{<udev-configuration>} record. So here, we
25722 extend that record by appending the list of rules it contains to the
25723 list of contributed rules.
25726 This is a string giving an overview of the service type. The string can
25727 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
25728 @command{guix system search} command searches these strings and displays
25729 them (@pxref{Invoking guix system}).
25732 There can be only one instance of an extensible service type such as
25733 @code{udev-service-type}. If there were more, the
25734 @code{service-extension} specifications would be ambiguous.
25736 Still here? The next section provides a reference of the programming
25737 interface for services.
25739 @node Service Reference
25740 @subsection Service Reference
25742 We have seen an overview of service types (@pxref{Service Types and
25743 Services}). This section provides a reference on how to manipulate
25744 services and service types. This interface is provided by the
25745 @code{(gnu services)} module.
25747 @deffn {Scheme Procedure} service @var{type} [@var{value}]
25748 Return a new service of @var{type}, a @code{<service-type>} object (see
25749 below.) @var{value} can be any object; it represents the parameters of
25750 this particular service instance.
25752 When @var{value} is omitted, the default value specified by @var{type}
25753 is used; if @var{type} does not specify a default value, an error is
25756 For instance, this:
25759 (service openssh-service-type)
25763 is equivalent to this:
25766 (service openssh-service-type
25767 (openssh-configuration))
25770 In both cases the result is an instance of @code{openssh-service-type}
25771 with the default configuration.
25774 @deffn {Scheme Procedure} service? @var{obj}
25775 Return true if @var{obj} is a service.
25778 @deffn {Scheme Procedure} service-kind @var{service}
25779 Return the type of @var{service}---i.e., a @code{<service-type>} object.
25782 @deffn {Scheme Procedure} service-value @var{service}
25783 Return the value associated with @var{service}. It represents its
25787 Here is an example of how a service is created and manipulated:
25791 (service nginx-service-type
25792 (nginx-configuration
25794 (log-directory log-directory)
25795 (run-directory run-directory)
25796 (file config-file))))
25801 (eq? (service-kind s) nginx-service-type)
25805 The @code{modify-services} form provides a handy way to change the
25806 parameters of some of the services of a list such as
25807 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
25808 evaluates to a list of services. Of course, you could always use
25809 standard list combinators such as @code{map} and @code{fold} to do that
25810 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
25811 @code{modify-services} simply provides a more concise form for this
25814 @deffn {Scheme Syntax} modify-services @var{services} @
25815 (@var{type} @var{variable} => @var{body}) @dots{}
25817 Modify the services listed in @var{services} according to the given
25818 clauses. Each clause has the form:
25821 (@var{type} @var{variable} => @var{body})
25824 where @var{type} is a service type---e.g.,
25825 @code{guix-service-type}---and @var{variable} is an identifier that is
25826 bound within the @var{body} to the service parameters---e.g., a
25827 @code{guix-configuration} instance---of the original service of that
25830 The @var{body} should evaluate to the new service parameters, which will
25831 be used to configure the new service. This new service will replace the
25832 original in the resulting list. Because a service's service parameters
25833 are created using @code{define-record-type*}, you can write a succinct
25834 @var{body} that evaluates to the new service parameters by using the
25835 @code{inherit} feature that @code{define-record-type*} provides.
25837 @xref{Using the Configuration System}, for example usage.
25841 Next comes the programming interface for service types. This is
25842 something you want to know when writing new service definitions, but not
25843 necessarily when simply looking for ways to customize your
25844 @code{operating-system} declaration.
25846 @deftp {Data Type} service-type
25847 @cindex service type
25848 This is the representation of a @dfn{service type} (@pxref{Service Types
25853 This is a symbol, used only to simplify inspection and debugging.
25855 @item @code{extensions}
25856 A non-empty list of @code{<service-extension>} objects (see below).
25858 @item @code{compose} (default: @code{#f})
25859 If this is @code{#f}, then the service type denotes services that cannot
25860 be extended---i.e., services that do not receive ``values'' from other
25863 Otherwise, it must be a one-argument procedure. The procedure is called
25864 by @code{fold-services} and is passed a list of values collected from
25865 extensions. It may return any single value.
25867 @item @code{extend} (default: @code{#f})
25868 If this is @code{#f}, services of this type cannot be extended.
25870 Otherwise, it must be a two-argument procedure: @code{fold-services}
25871 calls it, passing it the initial value of the service as the first
25872 argument and the result of applying @code{compose} to the extension
25873 values as the second argument. It must return a value that is a valid
25874 parameter value for the service instance.
25877 @xref{Service Types and Services}, for examples.
25880 @deffn {Scheme Procedure} service-extension @var{target-type} @
25882 Return a new extension for services of type @var{target-type}.
25883 @var{compute} must be a one-argument procedure: @code{fold-services}
25884 calls it, passing it the value associated with the service that provides
25885 the extension; it must return a valid value for the target service.
25888 @deffn {Scheme Procedure} service-extension? @var{obj}
25889 Return true if @var{obj} is a service extension.
25892 Occasionally, you might want to simply extend an existing service. This
25893 involves creating a new service type and specifying the extension of
25894 interest, which can be verbose; the @code{simple-service} procedure
25895 provides a shorthand for this.
25897 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
25898 Return a service that extends @var{target} with @var{value}. This works
25899 by creating a singleton service type @var{name}, of which the returned
25900 service is an instance.
25902 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
25906 (simple-service 'my-mcron-job mcron-service-type
25907 #~(job '(next-hour (3)) "guix gc -F 2G"))
25911 At the core of the service abstraction lies the @code{fold-services}
25912 procedure, which is responsible for ``compiling'' a list of services
25913 down to a single directory that contains everything needed to boot and
25914 run the system---the directory shown by the @command{guix system build}
25915 command (@pxref{Invoking guix system}). In essence, it propagates
25916 service extensions down the service graph, updating each node parameters
25917 on the way, until it reaches the root node.
25919 @deffn {Scheme Procedure} fold-services @var{services} @
25920 [#:target-type @var{system-service-type}]
25921 Fold @var{services} by propagating their extensions down to the root of
25922 type @var{target-type}; return the root service adjusted accordingly.
25925 Lastly, the @code{(gnu services)} module also defines several essential
25926 service types, some of which are listed below.
25928 @defvr {Scheme Variable} system-service-type
25929 This is the root of the service graph. It produces the system directory
25930 as returned by the @command{guix system build} command.
25933 @defvr {Scheme Variable} boot-service-type
25934 The type of the ``boot service'', which produces the @dfn{boot script}.
25935 The boot script is what the initial RAM disk runs when booting.
25938 @defvr {Scheme Variable} etc-service-type
25939 The type of the @file{/etc} service. This service is used to create
25940 files under @file{/etc} and can be extended by
25941 passing it name/file tuples such as:
25944 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
25947 In this example, the effect would be to add an @file{/etc/issue} file
25948 pointing to the given file.
25951 @defvr {Scheme Variable} setuid-program-service-type
25952 Type for the ``setuid-program service''. This service collects lists of
25953 executable file names, passed as gexps, and adds them to the set of
25954 setuid-root programs on the system (@pxref{Setuid Programs}).
25957 @defvr {Scheme Variable} profile-service-type
25958 Type of the service that populates the @dfn{system profile}---i.e., the
25959 programs under @file{/run/current-system/profile}. Other services can
25960 extend it by passing it lists of packages to add to the system profile.
25964 @node Shepherd Services
25965 @subsection Shepherd Services
25967 @cindex shepherd services
25969 @cindex init system
25970 The @code{(gnu services shepherd)} module provides a way to define
25971 services managed by the GNU@tie{}Shepherd, which is the
25972 initialization system---the first process that is started when the
25973 system boots, also known as PID@tie{}1
25974 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
25976 Services in the Shepherd can depend on each other. For instance, the
25977 SSH daemon may need to be started after the syslog daemon has been
25978 started, which in turn can only happen once all the file systems have
25979 been mounted. The simple operating system defined earlier (@pxref{Using
25980 the Configuration System}) results in a service graph like this:
25982 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
25984 You can actually generate such a graph for any operating system
25985 definition using the @command{guix system shepherd-graph} command
25986 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
25988 The @code{%shepherd-root-service} is a service object representing
25989 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
25990 by passing it lists of @code{<shepherd-service>} objects.
25992 @deftp {Data Type} shepherd-service
25993 The data type representing a service managed by the Shepherd.
25996 @item @code{provision}
25997 This is a list of symbols denoting what the service provides.
25999 These are the names that may be passed to @command{herd start},
26000 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
26001 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
26002 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
26004 @item @code{requirement} (default: @code{'()})
26005 List of symbols denoting the Shepherd services this one depends on.
26007 @cindex one-shot services, for the Shepherd
26008 @item @code{one-shot?} (default: @code{#f})
26009 Whether this service is @dfn{one-shot}. One-shot services stop immediately
26010 after their @code{start} action has completed. @xref{Slots of services,,,
26011 shepherd, The GNU Shepherd Manual}, for more info.
26013 @item @code{respawn?} (default: @code{#t})
26014 Whether to restart the service when it stops, for instance when the
26015 underlying process dies.
26018 @itemx @code{stop} (default: @code{#~(const #f)})
26019 The @code{start} and @code{stop} fields refer to the Shepherd's
26020 facilities to start and stop processes (@pxref{Service De- and
26021 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
26022 G-expressions that get expanded in the Shepherd configuration file
26023 (@pxref{G-Expressions}).
26025 @item @code{actions} (default: @code{'()})
26026 @cindex actions, of Shepherd services
26027 This is a list of @code{shepherd-action} objects (see below) defining
26028 @dfn{actions} supported by the service, in addition to the standard
26029 @code{start} and @code{stop} actions. Actions listed here become available as
26030 @command{herd} sub-commands:
26033 herd @var{action} @var{service} [@var{arguments}@dots{}]
26036 @item @code{auto-start?} (default: @code{#t})
26037 Whether this service should be started automatically by the Shepherd. If it
26038 is @code{#f} the service has to be started manually with @code{herd start}.
26040 @item @code{documentation}
26041 A documentation string, as shown when running:
26044 herd doc @var{service-name}
26047 where @var{service-name} is one of the symbols in @code{provision}
26048 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
26050 @item @code{modules} (default: @code{%default-modules})
26051 This is the list of modules that must be in scope when @code{start} and
26052 @code{stop} are evaluated.
26057 @deftp {Data Type} shepherd-action
26058 This is the data type that defines additional actions implemented by a
26059 Shepherd service (see above).
26063 Symbol naming the action.
26065 @item documentation
26066 This is a documentation string for the action. It can be viewed by running:
26069 herd doc @var{service} action @var{action}
26073 This should be a gexp that evaluates to a procedure of at least one argument,
26074 which is the ``running value'' of the service (@pxref{Slots of services,,,
26075 shepherd, The GNU Shepherd Manual}).
26078 The following example defines an action called @code{say-hello} that kindly
26084 (documentation "Say hi!")
26085 (procedure #~(lambda (running . args)
26086 (format #t "Hello, friend! arguments: ~s\n"
26091 Assuming this action is added to the @code{example} service, then you can do:
26094 # herd say-hello example
26095 Hello, friend! arguments: ()
26096 # herd say-hello example a b c
26097 Hello, friend! arguments: ("a" "b" "c")
26100 This, as you can see, is a fairly sophisticated way to say hello.
26101 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
26105 @defvr {Scheme Variable} shepherd-root-service-type
26106 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
26108 This is the service type that extensions target when they want to create
26109 shepherd services (@pxref{Service Types and Services}, for an example).
26110 Each extension must pass a list of @code{<shepherd-service>}.
26113 @defvr {Scheme Variable} %shepherd-root-service
26114 This service represents PID@tie{}1.
26118 @node Documentation
26119 @chapter Documentation
26121 @cindex documentation, searching for
26122 @cindex searching for documentation
26123 @cindex Info, documentation format
26125 @cindex manual pages
26126 In most cases packages installed with Guix come with documentation.
26127 There are two main documentation formats: ``Info'', a browseable
26128 hypertext format used for GNU software, and ``manual pages'' (or ``man
26129 pages''), the linear documentation format traditionally found on Unix.
26130 Info manuals are accessed with the @command{info} command or with Emacs,
26131 and man pages are accessed using @command{man}.
26133 You can look for documentation of software installed on your system by
26134 keyword. For example, the following command searches for information
26135 about ``TLS'' in Info manuals:
26139 "(emacs)Network Security" -- STARTTLS
26140 "(emacs)Network Security" -- TLS
26141 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
26142 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
26147 The command below searches for the same keyword in man pages:
26151 SSL (7) - OpenSSL SSL/TLS library
26152 certtool (1) - GnuTLS certificate tool
26156 These searches are purely local to your computer so you have the
26157 guarantee that documentation you find corresponds to what you have
26158 actually installed, you can access it off-line, and your privacy is
26161 Once you have these results, you can view the relevant documentation by
26165 $ info "(gnutls)Core TLS API"
26175 Info manuals contain sections and indices as well as hyperlinks like
26176 those found in Web pages. The @command{info} reader (@pxref{Top, Info
26177 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
26178 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
26179 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
26180 Introduction}, for an introduction to Info navigation.
26182 @node Installing Debugging Files
26183 @chapter Installing Debugging Files
26185 @cindex debugging files
26186 Program binaries, as produced by the GCC compilers for instance, are
26187 typically written in the ELF format, with a section containing
26188 @dfn{debugging information}. Debugging information is what allows the
26189 debugger, GDB, to map binary code to source code; it is required to
26190 debug a compiled program in good conditions.
26192 The problem with debugging information is that is takes up a fair amount
26193 of disk space. For example, debugging information for the GNU C Library
26194 weighs in at more than 60 MiB. Thus, as a user, keeping all the
26195 debugging info of all the installed programs is usually not an option.
26196 Yet, space savings should not come at the cost of an impediment to
26197 debugging---especially in the GNU system, which should make it easier
26198 for users to exert their computing freedom (@pxref{GNU Distribution}).
26200 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
26201 mechanism that allows users to get the best of both worlds: debugging
26202 information can be stripped from the binaries and stored in separate
26203 files. GDB is then able to load debugging information from those files,
26204 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
26207 The GNU distribution takes advantage of this by storing debugging
26208 information in the @code{lib/debug} sub-directory of a separate package
26209 output unimaginatively called @code{debug} (@pxref{Packages with
26210 Multiple Outputs}). Users can choose to install the @code{debug} output
26211 of a package when they need it. For instance, the following command
26212 installs the debugging information for the GNU C Library and for GNU
26216 guix install glibc:debug guile:debug
26219 GDB must then be told to look for debug files in the user's profile, by
26220 setting the @code{debug-file-directory} variable (consider setting it
26221 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
26225 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
26228 From there on, GDB will pick up debugging information from the
26229 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
26231 In addition, you will most likely want GDB to be able to show the source
26232 code being debugged. To do that, you will have to unpack the source
26233 code of the package of interest (obtained with @code{guix build
26234 --source}, @pxref{Invoking guix build}), and to point GDB to that source
26235 directory using the @code{directory} command (@pxref{Source Path,
26236 @code{directory},, gdb, Debugging with GDB}).
26238 @c XXX: keep me up-to-date
26239 The @code{debug} output mechanism in Guix is implemented by the
26240 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
26241 opt-in---debugging information is available only for the packages
26242 with definitions explicitly declaring a @code{debug} output. This may be
26243 changed to opt-out in the future if our build farm servers can handle
26244 the load. To check whether a package has a @code{debug} output, use
26245 @command{guix package --list-available} (@pxref{Invoking guix package}).
26248 @node Security Updates
26249 @chapter Security Updates
26251 @cindex security updates
26252 @cindex security vulnerabilities
26253 Occasionally, important security vulnerabilities are discovered in software
26254 packages and must be patched. Guix developers try hard to keep track of
26255 known vulnerabilities and to apply fixes as soon as possible in the
26256 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
26257 containing only security updates.) The @command{guix lint} tool helps
26258 developers find out about vulnerable versions of software packages in the
26263 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
26264 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
26265 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
26269 @xref{Invoking guix lint}, for more information.
26272 As of version @value{VERSION}, the feature described below is considered
26276 Guix follows a functional
26277 package management discipline (@pxref{Introduction}), which implies
26278 that, when a package is changed, @emph{every package that depends on it}
26279 must be rebuilt. This can significantly slow down the deployment of
26280 fixes in core packages such as libc or Bash, since basically the whole
26281 distribution would need to be rebuilt. Using pre-built binaries helps
26282 (@pxref{Substitutes}), but deployment may still take more time than
26286 To address this, Guix implements @dfn{grafts}, a mechanism that allows
26287 for fast deployment of critical updates without the costs associated
26288 with a whole-distribution rebuild. The idea is to rebuild only the
26289 package that needs to be patched, and then to ``graft'' it onto packages
26290 explicitly installed by the user and that were previously referring to
26291 the original package. The cost of grafting is typically very low, and
26292 order of magnitudes lower than a full rebuild of the dependency chain.
26294 @cindex replacements of packages, for grafts
26295 For instance, suppose a security update needs to be applied to Bash.
26296 Guix developers will provide a package definition for the ``fixed''
26297 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
26298 Packages}). Then, the original package definition is augmented with a
26299 @code{replacement} field pointing to the package containing the bug fix:
26306 (replacement bash-fixed)))
26309 From there on, any package depending directly or indirectly on Bash---as
26310 reported by @command{guix gc --requisites} (@pxref{Invoking guix
26311 gc})---that is installed is automatically ``rewritten'' to refer to
26312 @code{bash-fixed} instead of @code{bash}. This grafting process takes
26313 time proportional to the size of the package, usually less than a
26314 minute for an ``average'' package on a recent machine. Grafting is
26315 recursive: when an indirect dependency requires grafting, then grafting
26316 ``propagates'' up to the package that the user is installing.
26318 Currently, the length of the name and version of the graft and that of
26319 the package it replaces (@code{bash-fixed} and @code{bash} in the example
26320 above) must be equal. This restriction mostly comes from the fact that
26321 grafting works by patching files, including binary files, directly.
26322 Other restrictions may apply: for instance, when adding a graft to a
26323 package providing a shared library, the original shared library and its
26324 replacement must have the same @code{SONAME} and be binary-compatible.
26326 The @option{--no-grafts} command-line option allows you to forcefully
26327 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
26331 guix build bash --no-grafts
26335 returns the store file name of the original Bash, whereas:
26342 returns the store file name of the ``fixed'', replacement Bash. This
26343 allows you to distinguish between the two variants of Bash.
26345 To verify which Bash your whole profile refers to, you can run
26346 (@pxref{Invoking guix gc}):
26349 guix gc -R `readlink -f ~/.guix-profile` | grep bash
26353 @dots{} and compare the store file names that you get with those above.
26354 Likewise for a complete Guix system generation:
26357 guix gc -R `guix system build my-config.scm` | grep bash
26360 Lastly, to check which Bash running processes are using, you can use the
26361 @command{lsof} command:
26364 lsof | grep /gnu/store/.*bash
26368 @node Bootstrapping
26369 @chapter Bootstrapping
26371 @c Adapted from the ELS 2013 paper.
26373 @cindex bootstrapping
26375 Bootstrapping in our context refers to how the distribution gets built
26376 ``from nothing''. Remember that the build environment of a derivation
26377 contains nothing but its declared inputs (@pxref{Introduction}). So
26378 there's an obvious chicken-and-egg problem: how does the first package
26379 get built? How does the first compiler get compiled? Note that this is
26380 a question of interest only to the curious hacker, not to the regular
26381 user, so you can shamelessly skip this section if you consider yourself
26382 a ``regular user''.
26384 @cindex bootstrap binaries
26385 The GNU system is primarily made of C code, with libc at its core. The
26386 GNU build system itself assumes the availability of a Bourne shell and
26387 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
26388 `grep'. Furthermore, build programs---programs that run
26389 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
26390 (@pxref{Derivations}). Consequently, to be able to build anything at
26391 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
26392 Binutils, libc, and the other packages mentioned above---the
26393 @dfn{bootstrap binaries}.
26395 These bootstrap binaries are ``taken for granted'', though we can also
26396 re-create them if needed (more on that later).
26398 @unnumberedsec Preparing to Use the Bootstrap Binaries
26400 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
26401 @c large image, it's hard to scroll. Oh well.
26402 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
26404 The figure above shows the very beginning of the dependency graph of the
26405 distribution, corresponding to the package definitions of the @code{(gnu
26406 packages bootstrap)} module. A similar figure can be generated with
26407 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
26410 guix graph -t derivation \
26411 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
26415 At this level of detail, things are
26416 slightly complex. First, Guile itself consists of an ELF executable,
26417 along with many source and compiled Scheme files that are dynamically
26418 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
26419 tarball shown in this graph. This tarball is part of Guix's ``source''
26420 distribution, and gets inserted into the store with @code{add-to-store}
26421 (@pxref{The Store}).
26423 But how do we write a derivation that unpacks this tarball and adds it
26424 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
26425 derivation---the first one that gets built---uses @code{bash} as its
26426 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
26427 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
26428 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
26429 the Guix source distribution, whose sole purpose is to allow the Guile
26430 tarball to be unpacked.
26432 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
26433 Guile that can be used to run subsequent build programs. Its first task
26434 is to download tarballs containing the other pre-built binaries---this
26435 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
26436 @code{ftp-client.scm} are used for this purpose. The
26437 @code{module-import.drv} derivations import those modules in a directory
26438 in the store, using the original layout. The
26439 @code{module-import-compiled.drv} derivations compile those modules, and
26440 write them in an output directory with the right layout. This
26441 corresponds to the @code{#:modules} argument of
26442 @code{build-expression->derivation} (@pxref{Derivations}).
26444 Finally, the various tarballs are unpacked by the
26445 derivations @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv},
26446 etc., at which point we have a working C tool chain.
26449 @unnumberedsec Building the Build Tools
26451 Bootstrapping is complete when we have a full tool chain that does not
26452 depend on the pre-built bootstrap tools discussed above. This
26453 no-dependency requirement is verified by checking whether the files of
26454 the final tool chain contain references to the @file{/gnu/store}
26455 directories of the bootstrap inputs. The process that leads to this
26456 ``final'' tool chain is described by the package definitions found in
26457 the @code{(gnu packages commencement)} module.
26459 The @command{guix graph} command allows us to ``zoom out'' compared to
26460 the graph above, by looking at the level of package objects instead of
26461 individual derivations---remember that a package may translate to
26462 several derivations, typically one derivation to download its source,
26463 one to build the Guile modules it needs, and one to actually build the
26464 package from source. The command:
26467 guix graph -t bag \
26468 -e '(@@@@ (gnu packages commencement)
26469 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
26473 produces the dependency graph leading to the ``final'' C
26474 library@footnote{You may notice the @code{glibc-intermediate} label,
26475 suggesting that it is not @emph{quite} final, but as a good
26476 approximation, we will consider it final.}, depicted below.
26478 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
26480 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
26481 The first tool that gets built with the bootstrap binaries is
26482 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
26483 for all the following packages. From there Findutils and Diffutils get
26486 Then come the first-stage Binutils and GCC, built as pseudo cross
26487 tools---i.e., with @code{--target} equal to @code{--host}. They are
26488 used to build libc. Thanks to this cross-build trick, this libc is
26489 guaranteed not to hold any reference to the initial tool chain.
26491 From there the final Binutils and GCC (not shown above) are built.
26493 from the final Binutils, and links programs against the just-built libc.
26494 This tool chain is used to build the other packages used by Guix and by
26495 the GNU Build System: Guile, Bash, Coreutils, etc.
26497 And voilà! At this point we have the complete set of build tools that
26498 the GNU Build System expects. These are in the @code{%final-inputs}
26499 variable of the @code{(gnu packages commencement)} module, and are
26500 implicitly used by any package that uses @code{gnu-build-system}
26501 (@pxref{Build Systems, @code{gnu-build-system}}).
26504 @unnumberedsec Building the Bootstrap Binaries
26506 @cindex bootstrap binaries
26507 Because the final tool chain does not depend on the bootstrap binaries,
26508 those rarely need to be updated. Nevertheless, it is useful to have an
26509 automated way to produce them, should an update occur, and this is what
26510 the @code{(gnu packages make-bootstrap)} module provides.
26512 The following command builds the tarballs containing the bootstrap
26513 binaries (Guile, Binutils, GCC, libc, and a tarball containing a mixture
26514 of Coreutils and other basic command-line tools):
26517 guix build bootstrap-tarballs
26520 The generated tarballs are those that should be referred to in the
26521 @code{(gnu packages bootstrap)} module mentioned at the beginning of
26524 Still here? Then perhaps by now you've started to wonder: when do we
26525 reach a fixed point? That is an interesting question! The answer is
26526 unknown, but if you would like to investigate further (and have
26527 significant computational and storage resources to do so), then let us
26530 @unnumberedsec Reducing the Set of Bootstrap Binaries
26532 Our bootstrap binaries currently include GCC, Guile, etc. That's a lot
26533 of binary code! Why is that a problem? It's a problem because these
26534 big chunks of binary code are practically non-auditable, which makes it
26535 hard to establish what source code produced them. Every unauditable
26536 binary also leaves us vulnerable to compiler backdoors as described by
26537 Ken Thompson in the 1984 paper @emph{Reflections on Trusting Trust}.
26539 This is mitigated by the fact that our bootstrap binaries were generated
26540 from an earlier Guix revision. Nevertheless it lacks the level of
26541 transparency that we get in the rest of the package dependency graph,
26542 where Guix always gives us a source-to-binary mapping. Thus, our goal
26543 is to reduce the set of bootstrap binaries to the bare minimum.
26545 The @uref{http://bootstrappable.org, Bootstrappable.org web site} lists
26546 on-going projects to do that. One of these is about replacing the
26547 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
26548 of increasing complexity, which could be built from source starting from
26549 a simple and auditable assembler. Your help is welcome!
26553 @chapter Porting to a New Platform
26555 As discussed above, the GNU distribution is self-contained, and
26556 self-containment is achieved by relying on pre-built ``bootstrap
26557 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
26558 operating system kernel, CPU architecture, and application binary
26559 interface (ABI). Thus, to port the distribution to a platform that is
26560 not yet supported, one must build those bootstrap binaries, and update
26561 the @code{(gnu packages bootstrap)} module to use them on that platform.
26563 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
26564 When everything goes well, and assuming the GNU tool chain supports the
26565 target platform, this can be as simple as running a command like this
26569 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
26572 For this to work, the @code{glibc-dynamic-linker} procedure in
26573 @code{(gnu packages bootstrap)} must be augmented to return the right
26574 file name for libc's dynamic linker on that platform; likewise,
26575 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
26576 taught about the new platform.
26578 Once these are built, the @code{(gnu packages bootstrap)} module needs
26579 to be updated to refer to these binaries on the target platform. That
26580 is, the hashes and URLs of the bootstrap tarballs for the new platform
26581 must be added alongside those of the currently supported platforms. The
26582 bootstrap Guile tarball is treated specially: it is expected to be
26583 available locally, and @file{gnu/local.mk} has rules to download it for
26584 the supported architectures; a rule for the new platform must be added
26587 In practice, there may be some complications. First, it may be that the
26588 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
26589 above) is not recognized by all the GNU tools. Typically, glibc
26590 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
26591 configure flag (see @code{gcc.scm} for examples of how to handle this).
26592 Second, some of the required packages could fail to build for that
26593 platform. Lastly, the generated binaries could be broken for some
26596 @c *********************************************************************
26597 @include contributing.texi
26599 @c *********************************************************************
26600 @node Acknowledgments
26601 @chapter Acknowledgments
26603 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
26604 which was designed and
26605 implemented by Eelco Dolstra, with contributions from other people (see
26606 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
26607 management, and promoted unprecedented features, such as transactional
26608 package upgrades and rollbacks, per-user profiles, and referentially
26609 transparent build processes. Without this work, Guix would not exist.
26611 The Nix-based software distributions, Nixpkgs and NixOS, have also been
26612 an inspiration for Guix.
26614 GNU@tie{}Guix itself is a collective work with contributions from a
26615 number of people. See the @file{AUTHORS} file in Guix for more
26616 information on these fine people. The @file{THANKS} file lists people
26617 who have helped by reporting bugs, taking care of the infrastructure,
26618 providing artwork and themes, making suggestions, and more---thank you!
26621 @c *********************************************************************
26622 @node GNU Free Documentation License
26623 @appendix GNU Free Documentation License
26624 @cindex license, GNU Free Documentation License
26625 @include fdl-1.3.texi
26627 @c *********************************************************************
26628 @node Concept Index
26629 @unnumbered Concept Index
26632 @node Programming Index
26633 @unnumbered Programming Index
26634 @syncodeindex tp fn
26635 @syncodeindex vr fn
26640 @c Local Variables:
26641 @c ispell-local-dictionary: "american";