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 OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=15145
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, 2020 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, 2019, 2020 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 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, 2019 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, 2019, 2020 Marius Bakke@*
50 Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
51 Copyright @copyright{} 2017, 2019, 2020 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018, 2019, 2020 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, 2020 Diego Nicola Barbato@*
67 Copyright @copyright{} 2019 Ivan Petkov@*
68 Copyright @copyright{} 2019 Jakob L. Kreuze@*
69 Copyright @copyright{} 2019 Kyle Andrews@*
70 Copyright @copyright{} 2019 Alex Griffin@*
71 Copyright @copyright{} 2019 Guillaume Le Vaillant@*
72 Copyright @copyright{} 2020 Leo Prikler@*
73 Copyright @copyright{} 2019, 2020 Simon Tournier@*
74 Copyright @copyright{} 2020 Wiktor Żelazny@*
75 Copyright @copyright{} 2020 Damien Cassou@*
76 Copyright @copyright{} 2020 Jakub Kądziołka@*
77 Copyright @copyright{} 2020 Jack Hill@*
78 Copyright @copyright{} 2020 Naga Malleswari@*
79 Copyright @copyright{} 2020 Brice Waegeneire@*
80 Copyright @copyright{} 2020 R Veera Kumar@*
81 Copyright @copyright{} 2020 Pierre Langlois@*
83 Permission is granted to copy, distribute and/or modify this document
84 under the terms of the GNU Free Documentation License, Version 1.3 or
85 any later version published by the Free Software Foundation; with no
86 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
87 copy of the license is included in the section entitled ``GNU Free
88 Documentation License''.
91 @dircategory System administration
93 * Guix: (guix). Manage installed software and system configuration.
94 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
95 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
96 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
97 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
98 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
101 @dircategory Software development
103 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
104 * guix build: (guix)Invoking guix build. Building packages.
105 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
109 @title GNU Guix Reference Manual
110 @subtitle Using the GNU Guix Functional Package Manager
111 @author The GNU Guix Developers
114 @vskip 0pt plus 1filll
115 Edition @value{EDITION} @*
123 @c *********************************************************************
127 This document describes GNU Guix version @value{VERSION}, a functional
128 package management tool written for the GNU system.
130 @c TRANSLATORS: You can replace the following paragraph with information on
131 @c how to join your own translation team and how to report issues with the
133 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
134 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
135 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
136 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
137 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
138 would like to translate it in your native language, consider joining the
139 @uref{https://translationproject.org/domain/guix-manual.html, Translation
143 * Introduction:: What is Guix about?
144 * Installation:: Installing Guix.
145 * System Installation:: Installing the whole operating system.
146 * Package Management:: Package installation, upgrade, etc.
147 * Development:: Guix-aided software development.
148 * Programming Interface:: Using Guix in Scheme.
149 * Utilities:: Package management commands.
150 * System Configuration:: Configuring the operating system.
151 * Documentation:: Browsing software user manuals.
152 * Installing Debugging Files:: Feeding the debugger.
153 * Security Updates:: Deploying security fixes quickly.
154 * Bootstrapping:: GNU/Linux built from scratch.
155 * Porting:: Targeting another platform or kernel.
156 * Contributing:: Your help needed!
158 * Acknowledgments:: Thanks!
159 * GNU Free Documentation License:: The license of this manual.
160 * Concept Index:: Concepts.
161 * Programming Index:: Data types, functions, and variables.
164 --- The Detailed Node Listing ---
168 * Managing Software the Guix Way:: What's special.
169 * GNU Distribution:: The packages and tools.
173 * Binary Installation:: Getting Guix running in no time!
174 * Requirements:: Software needed to build and run Guix.
175 * Running the Test Suite:: Testing Guix.
176 * Setting Up the Daemon:: Preparing the build daemon's environment.
177 * Invoking guix-daemon:: Running the build daemon.
178 * Application Setup:: Application-specific setup.
180 Setting Up the Daemon
182 * Build Environment Setup:: Preparing the isolated build environment.
183 * Daemon Offload Setup:: Offloading builds to remote machines.
184 * SELinux Support:: Using an SELinux policy for the daemon.
188 * Limitations:: What you can expect.
189 * Hardware Considerations:: Supported hardware.
190 * USB Stick and DVD Installation:: Preparing the installation medium.
191 * Preparing for Installation:: Networking, partitioning, etc.
192 * Guided Graphical Installation:: Easy graphical installation.
193 * Manual Installation:: Manual installation for wizards.
194 * After System Installation:: When installation succeeded.
195 * Installing Guix in a VM:: Guix System playground.
196 * Building the Installation Image:: How this comes to be.
200 * Keyboard Layout and Networking and Partitioning:: Initial setup.
201 * Proceeding with the Installation:: Installing.
205 * Features:: How Guix will make your life brighter.
206 * Invoking guix package:: Package installation, removal, etc.
207 * Substitutes:: Downloading pre-built binaries.
208 * Packages with Multiple Outputs:: Single source package, multiple outputs.
209 * Invoking guix gc:: Running the garbage collector.
210 * Invoking guix pull:: Fetching the latest Guix and distribution.
211 * Channels:: Customizing the package collection.
212 * Invoking guix time-machine:: Running an older revision of Guix.
213 * Inferiors:: Interacting with another revision of Guix.
214 * Invoking guix describe:: Display information about your Guix revision.
215 * Invoking guix archive:: Exporting and importing store files.
219 * Official Substitute Server:: One particular source of substitutes.
220 * Substitute Server Authorization:: How to enable or disable substitutes.
221 * Substitute Authentication:: How Guix verifies substitutes.
222 * Proxy Settings:: How to get substitutes via proxy.
223 * Substitution Failure:: What happens when substitution fails.
224 * On Trusting Binaries:: How can you trust that binary blob?
228 * Invoking guix environment:: Setting up development environments.
229 * Invoking guix pack:: Creating software bundles.
231 Programming Interface
233 * Package Modules:: Packages from the programmer's viewpoint.
234 * Defining Packages:: Defining new packages.
235 * Build Systems:: Specifying how packages are built.
236 * The Store:: Manipulating the package store.
237 * Derivations:: Low-level interface to package derivations.
238 * The Store Monad:: Purely functional interface to the store.
239 * G-Expressions:: Manipulating build expressions.
240 * Invoking guix repl:: Fiddling with Guix interactively.
244 * package Reference:: The package data type.
245 * origin Reference:: The origin data type.
249 * Invoking guix build:: Building packages from the command line.
250 * Invoking guix edit:: Editing package definitions.
251 * Invoking guix download:: Downloading a file and printing its hash.
252 * Invoking guix hash:: Computing the cryptographic hash of a file.
253 * Invoking guix import:: Importing package definitions.
254 * Invoking guix refresh:: Updating package definitions.
255 * Invoking guix lint:: Finding errors in package definitions.
256 * Invoking guix size:: Profiling disk usage.
257 * Invoking guix graph:: Visualizing the graph of packages.
258 * Invoking guix publish:: Sharing substitutes.
259 * Invoking guix challenge:: Challenging substitute servers.
260 * Invoking guix copy:: Copying to and from a remote store.
261 * Invoking guix container:: Process isolation.
262 * Invoking guix weather:: Assessing substitute availability.
263 * Invoking guix processes:: Listing client processes.
265 Invoking @command{guix build}
267 * Common Build Options:: Build options for most commands.
268 * Package Transformation Options:: Creating variants of packages.
269 * Additional Build Options:: Options specific to 'guix build'.
270 * Debugging Build Failures:: Real life packaging experience.
274 * Using the Configuration System:: Customizing your GNU system.
275 * operating-system Reference:: Detail of operating-system declarations.
276 * File Systems:: Configuring file system mounts.
277 * Mapped Devices:: Block device extra processing.
278 * User Accounts:: Specifying user accounts.
279 * Keyboard Layout:: How the system interprets key strokes.
280 * Locales:: Language and cultural convention settings.
281 * Services:: Specifying system services.
282 * Setuid Programs:: Programs running with root privileges.
283 * X.509 Certificates:: Authenticating HTTPS servers.
284 * Name Service Switch:: Configuring libc's name service switch.
285 * Initial RAM Disk:: Linux-Libre bootstrapping.
286 * Bootloader Configuration:: Configuring the boot loader.
287 * Invoking guix system:: Instantiating a system configuration.
288 * Invoking guix deploy:: Deploying a system configuration to a remote host.
289 * Running Guix in a VM:: How to run Guix System in a virtual machine.
290 * Defining Services:: Adding new service definitions.
294 * Base Services:: Essential system services.
295 * Scheduled Job Execution:: The mcron service.
296 * Log Rotation:: The rottlog service.
297 * Networking Services:: Network setup, SSH daemon, etc.
298 * X Window:: Graphical display.
299 * Printing Services:: Local and remote printer support.
300 * Desktop Services:: D-Bus and desktop services.
301 * Sound Services:: ALSA and Pulseaudio services.
302 * Database Services:: SQL databases, key-value stores, etc.
303 * Mail Services:: IMAP, POP3, SMTP, and all that.
304 * Messaging Services:: Messaging services.
305 * Telephony Services:: Telephony services.
306 * Monitoring Services:: Monitoring services.
307 * Kerberos Services:: Kerberos services.
308 * Web Services:: Web servers.
309 * Certificate Services:: TLS certificates via Let's Encrypt.
310 * DNS Services:: DNS daemons.
311 * VPN Services:: VPN daemons.
312 * Network File System:: NFS related services.
313 * Continuous Integration:: The Cuirass service.
314 * Power Management Services:: Extending battery life.
315 * Audio Services:: The MPD.
316 * Virtualization Services:: Virtualization services.
317 * Version Control Services:: Providing remote access to Git repositories.
318 * Game Services:: Game servers.
319 * PAM Mount Service:: Service to mount volumes when logging in.
320 * Linux Services:: Services tied to the Linux kernel.
321 * Miscellaneous Services:: Other services.
325 * Service Composition:: The model for composing services.
326 * Service Types and Services:: Types and services.
327 * Service Reference:: API reference.
328 * Shepherd Services:: A particular type of service.
333 @c *********************************************************************
335 @chapter Introduction
338 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
339 using the international phonetic alphabet (IPA).} is a package
340 management tool for and distribution of the GNU system.
341 Guix makes it easy for unprivileged
342 users to install, upgrade, or remove software packages, to roll back to a
343 previous package set, to build packages from source, and generally
344 assists with the creation and maintenance of software environments.
347 @cindex GuixSD, now Guix System
348 @cindex Guix System Distribution, now Guix System
349 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
350 complements the available tools without interference (@pxref{Installation}),
351 or you can use it as a standalone operating system distribution,
352 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
353 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
354 group everything under the ``Guix'' banner since, after all, Guix System is
355 readily available through the @command{guix system} command, even if you're
356 using a different distro underneath!}. @xref{GNU Distribution}.
359 * Managing Software the Guix Way:: What's special.
360 * GNU Distribution:: The packages and tools.
363 @node Managing Software the Guix Way
364 @section Managing Software the Guix Way
366 @cindex user interfaces
367 Guix provides a command-line package management interface
368 (@pxref{Package Management}), tools to help with software development
369 (@pxref{Development}), command-line utilities for more advanced usage,
370 (@pxref{Utilities}), as well as Scheme programming interfaces
371 (@pxref{Programming Interface}).
373 Its @dfn{build daemon} is responsible for building packages on behalf of
374 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
375 binaries from authorized sources (@pxref{Substitutes}).
377 @cindex extensibility of the distribution
378 @cindex customization, of packages
379 Guix includes package definitions for many GNU and non-GNU packages, all
380 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
381 user's computing freedom}. It is @emph{extensible}: users can write
382 their own package definitions (@pxref{Defining Packages}) and make them
383 available as independent package modules (@pxref{Package Modules}). It
384 is also @emph{customizable}: users can @emph{derive} specialized package
385 definitions from existing ones, including from the command line
386 (@pxref{Package Transformation Options}).
388 @cindex functional package management
390 Under the hood, Guix implements the @dfn{functional package management}
391 discipline pioneered by Nix (@pxref{Acknowledgments}).
392 In Guix, the package build and installation process is seen
393 as a @emph{function}, in the mathematical sense. That function takes inputs,
394 such as build scripts, a compiler, and libraries, and
395 returns an installed package. As a pure function, its result depends
396 solely on its inputs---for instance, it cannot refer to software or
397 scripts that were not explicitly passed as inputs. A build function
398 always produces the same result when passed a given set of inputs. It
399 cannot alter the environment of the running system in
400 any way; for instance, it cannot create, modify, or delete files outside
401 of its build and installation directories. This is achieved by running
402 build processes in isolated environments (or @dfn{containers}), where only their
403 explicit inputs are visible.
406 The result of package build functions is @dfn{cached} in the file
407 system, in a special directory called @dfn{the store} (@pxref{The
408 Store}). Each package is installed in a directory of its own in the
409 store---by default under @file{/gnu/store}. The directory name contains
410 a hash of all the inputs used to build that package; thus, changing an
411 input yields a different directory name.
413 This approach is the foundation for the salient features of Guix: support
414 for transactional package upgrade and rollback, per-user installation, and
415 garbage collection of packages (@pxref{Features}).
418 @node GNU Distribution
419 @section GNU Distribution
422 Guix comes with a distribution of the GNU system consisting entirely of
423 free software@footnote{The term ``free'' here refers to the
424 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
425 users of that software}.}. The
426 distribution can be installed on its own (@pxref{System Installation}),
427 but it is also possible to install Guix as a package manager on top of
428 an installed GNU/Linux system (@pxref{Installation}). When we need to
429 distinguish between the two, we refer to the standalone distribution as
432 The distribution provides core GNU packages such as GNU libc, GCC, and
433 Binutils, as well as many GNU and non-GNU applications. The complete
434 list of available packages can be browsed
435 @url{https://www.gnu.org/software/guix/packages,on-line} or by
436 running @command{guix package} (@pxref{Invoking guix package}):
439 guix package --list-available
442 Our goal is to provide a practical 100% free software distribution of
443 Linux-based and other variants of GNU, with a focus on the promotion and
444 tight integration of GNU components, and an emphasis on programs and
445 tools that help users exert that freedom.
447 Packages are currently available on the following platforms:
452 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
455 Intel 32-bit architecture (IA32), Linux-Libre kernel;
458 ARMv7-A architecture with hard float, Thumb-2 and NEON,
459 using the EABI hard-float application binary interface (ABI),
460 and Linux-Libre kernel.
463 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
466 little-endian 64-bit MIPS processors, specifically the Loongson series,
467 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
468 supported; in particular, the project's build farms no longer provide
469 substitutes for this architecture.
473 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
474 configuration and Guix takes care of instantiating the configuration in a
475 transactional, reproducible, and stateless fashion (@pxref{System
476 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
477 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
478 Manual}), the well-known GNU utilities and tool chain, as well as the
479 graphical environment or system services of your choice.
481 Guix System is available on all the above platforms except
482 @code{mips64el-linux}.
485 For information on porting to other architectures or kernels,
488 Building this distribution is a cooperative effort, and you are invited
489 to join! @xref{Contributing}, for information about how you can help.
492 @c *********************************************************************
494 @chapter Installation
496 @cindex installing Guix
499 We recommend the use of this
500 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
501 shell installer script} to install Guix on top of a running GNU/Linux system,
502 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
503 with the installation of the package manager, which can be done on top of a
504 running GNU/Linux system. If, instead, you want to install the complete GNU
505 operating system, @pxref{System Installation}.} The script automates the
506 download, installation, and initial configuration of Guix. It should be run
510 @cindex foreign distro
511 @cindex directories related to foreign distro
512 When installed on a foreign distro, GNU@tie{}Guix complements the available
513 tools without interference. Its data lives exclusively in two directories,
514 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
515 such as @file{/etc}, are left untouched.
517 Once installed, Guix can be updated by running @command{guix pull}
518 (@pxref{Invoking guix pull}).
520 If you prefer to perform the installation steps manually or want to tweak
521 them, you may find the following subsections useful. They describe the
522 software requirements of Guix, as well as how to install it manually and get
526 * Binary Installation:: Getting Guix running in no time!
527 * Requirements:: Software needed to build and run Guix.
528 * Running the Test Suite:: Testing Guix.
529 * Setting Up the Daemon:: Preparing the build daemon's environment.
530 * Invoking guix-daemon:: Running the build daemon.
531 * Application Setup:: Application-specific setup.
532 * Upgrading Guix:: Upgrading Guix and its build daemon.
535 @node Binary Installation
536 @section Binary Installation
538 @cindex installing Guix from binaries
539 @cindex installer script
540 This section describes how to install Guix on an arbitrary system from a
541 self-contained tarball providing binaries for Guix and for all its
542 dependencies. This is often quicker than installing from source, which
543 is described in the next sections. The only requirement is to have
546 @c Note duplicated from the ``Installation'' node.
548 We recommend the use of this
549 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
550 shell installer script}. The script automates the download, installation, and
551 initial configuration steps described below. It should be run as the root
552 user. As root, you can thus run this:
556 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
557 chmod +x guix-install.sh
562 Installing goes along these lines:
566 @cindex downloading Guix binary
567 Download the binary tarball from
568 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz},
569 where @var{system} is @code{x86_64-linux} for an @code{x86_64} machine
570 already running the kernel Linux, and so on.
572 @c The following is somewhat duplicated in ``System Installation''.
573 Make sure to download the associated @file{.sig} file and to verify the
574 authenticity of the tarball against it, along these lines:
577 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
578 $ gpg --verify guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
581 If that command fails because you do not have the required public key,
582 then run this command to import it:
585 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
586 -qO - | gpg --import -
590 and rerun the @code{gpg --verify} command.
592 Take note that a warning like ``This key is not certified with a trusted
593 signature!'' is normal.
595 @c end authentication part
598 Now, you need to become the @code{root} user. Depending on your distribution,
599 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
603 # tar --warning=no-timestamp -xf \
604 /path/to/guix-binary-@value{VERSION}.@var{system}.tar.xz
605 # mv var/guix /var/ && mv gnu /
608 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
609 The latter contains a ready-to-use profile for @code{root} (see next
612 Do @emph{not} unpack the tarball on a working Guix system since that
613 would overwrite its own essential files.
615 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
616 not emit warnings about ``implausibly old time stamps'' (such
617 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
619 They stem from the fact that all the
620 files in the archive have their modification time set to zero (which
621 means January 1st, 1970.) This is done on purpose to make sure the
622 archive content is independent of its creation time, thus making it
626 Make the profile available under @file{~root/.config/guix/current}, which is
627 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
630 # mkdir -p ~root/.config/guix
631 # ln -sf /var/guix/profiles/per-user/root/current-guix \
632 ~root/.config/guix/current
635 Source @file{etc/profile} to augment @code{PATH} and other relevant
636 environment variables:
639 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
640 source $GUIX_PROFILE/etc/profile
644 Create the group and user accounts for build users as explained below
645 (@pxref{Build Environment Setup}).
648 Run the daemon, and set it to automatically start on boot.
650 If your host distro uses the systemd init system, this can be achieved
653 @c Versions of systemd that supported symlinked service files are not
654 @c yet widely deployed, so we should suggest that users copy the service
657 @c See this thread for more information:
658 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
661 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
663 # systemctl enable --now guix-daemon
666 If your host distro uses the Upstart init system:
669 # initctl reload-configuration
670 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
675 Otherwise, you can still start the daemon manually with:
678 # ~root/.config/guix/current/bin/guix-daemon \
679 --build-users-group=guixbuild
683 Make the @command{guix} command available to other users on the machine,
687 # mkdir -p /usr/local/bin
689 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
692 It is also a good idea to make the Info version of this manual available
696 # mkdir -p /usr/local/share/info
697 # cd /usr/local/share/info
698 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
702 That way, assuming @file{/usr/local/share/info} is in the search path,
703 running @command{info guix} will open this manual (@pxref{Other Info
704 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
708 @cindex substitutes, authorization thereof
709 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
710 (@pxref{Substitutes}), authorize them:
713 # guix archive --authorize < \
714 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
718 Each user may need to perform a few additional steps to make their Guix
719 environment ready for use, @pxref{Application Setup}.
722 Voilà, the installation is complete!
724 You can confirm that Guix is working by installing a sample package into
731 The binary installation tarball can be (re)produced and verified simply
732 by running the following command in the Guix source tree:
735 make guix-binary.@var{system}.tar.xz
739 ...@: which, in turn, runs:
742 guix pack -s @var{system} --localstatedir \
743 --profile-name=current-guix guix
746 @xref{Invoking guix pack}, for more info on this handy tool.
749 @section Requirements
751 This section lists requirements when building Guix from source. The
752 build procedure for Guix is the same as for other GNU software, and is
753 not covered here. Please see the files @file{README} and @file{INSTALL}
754 in the Guix source tree for additional details.
756 @cindex official website
757 GNU Guix is available for download from its website at
758 @url{https://www.gnu.org/software/guix/}.
760 GNU Guix depends on the following packages:
763 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
765 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
768 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
769 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
770 Guile,, gnutls-guile, GnuTLS-Guile});
772 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
775 @c FIXME: Specify a version number once a release has been made.
776 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
778 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON} 3.x;
779 @item @url{https://zlib.net, zlib};
780 @item @url{https://www.gnu.org/software/make/, GNU Make}.
783 The following dependencies are optional:
787 @c Note: We need at least 0.12.0 for 'userauth-gssapi!'.
788 Support for build offloading (@pxref{Daemon Offload Setup}) and
789 @command{guix copy} (@pxref{Invoking guix copy}) depends on
790 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
791 version 0.12.0 or later.
794 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
795 substitutes can be used and @command{guix publish} can compress substitutes
799 When @url{http://www.bzip.org, libbz2} is available,
800 @command{guix-daemon} can use it to compress build logs.
803 Unless @code{--disable-daemon} was passed to @command{configure}, the
804 following packages are also needed:
807 @item @url{https://gnupg.org/, GNU libgcrypt};
808 @item @url{https://sqlite.org, SQLite 3};
809 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
813 @cindex state directory
814 When configuring Guix on a system that already has a Guix installation,
815 be sure to specify the same state directory as the existing installation
816 using the @code{--localstatedir} option of the @command{configure}
817 script (@pxref{Directory Variables, @code{localstatedir},, standards,
818 GNU Coding Standards}). Usually, this @var{localstatedir} option is
819 set to the value @file{/var}. The @command{configure} script protects
820 against unintended misconfiguration of @var{localstatedir} so you do not
821 inadvertently corrupt your store (@pxref{The Store}).
823 @node Running the Test Suite
824 @section Running the Test Suite
827 After a successful @command{configure} and @code{make} run, it is a good
828 idea to run the test suite. It can help catch issues with the setup or
829 environment, or bugs in Guix itself---and really, reporting test
830 failures is a good way to help improve the software. To run the test
837 Test cases can run in parallel: you can use the @code{-j} option of
838 GNU@tie{}make to speed things up. The first run may take a few minutes
839 on a recent machine; subsequent runs will be faster because the store
840 that is created for test purposes will already have various things in
843 It is also possible to run a subset of the tests by defining the
844 @code{TESTS} makefile variable as in this example:
847 make check TESTS="tests/store.scm tests/cpio.scm"
850 By default, tests results are displayed at a file level. In order to
851 see the details of every individual test cases, it is possible to define
852 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
855 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
858 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
859 @file{test-suite.log} file. Please specify the Guix version being used
860 as well as version numbers of the dependencies (@pxref{Requirements}) in
863 Guix also comes with a whole-system test suite that tests complete
864 Guix System instances. It can only run on systems where
865 Guix is already installed, using:
872 or, again, by defining @code{TESTS} to select a subset of tests to run:
875 make check-system TESTS="basic mcron"
878 These system tests are defined in the @code{(gnu tests @dots{})}
879 modules. They work by running the operating systems under test with
880 lightweight instrumentation in a virtual machine (VM). They can be
881 computationally intensive or rather cheap, depending on whether
882 substitutes are available for their dependencies (@pxref{Substitutes}).
883 Some of them require a lot of storage space to hold VM images.
885 Again in case of test failures, please send @email{bug-guix@@gnu.org}
888 @node Setting Up the Daemon
889 @section Setting Up the Daemon
892 Operations such as building a package or running the garbage collector
893 are all performed by a specialized process, the @dfn{build daemon}, on
894 behalf of clients. Only the daemon may access the store and its
895 associated database. Thus, any operation that manipulates the store
896 goes through the daemon. For instance, command-line tools such as
897 @command{guix package} and @command{guix build} communicate with the
898 daemon (@i{via} remote procedure calls) to instruct it what to do.
900 The following sections explain how to prepare the build daemon's
901 environment. See also @ref{Substitutes}, for information on how to allow
902 the daemon to download pre-built binaries.
905 * Build Environment Setup:: Preparing the isolated build environment.
906 * Daemon Offload Setup:: Offloading builds to remote machines.
907 * SELinux Support:: Using an SELinux policy for the daemon.
910 @node Build Environment Setup
911 @subsection Build Environment Setup
913 @cindex build environment
914 In a standard multi-user setup, Guix and its daemon---the
915 @command{guix-daemon} program---are installed by the system
916 administrator; @file{/gnu/store} is owned by @code{root} and
917 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
918 Guix tools to build packages or otherwise access the store, and the
919 daemon will do it on their behalf, ensuring that the store is kept in a
920 consistent state, and allowing built packages to be shared among users.
923 When @command{guix-daemon} runs as @code{root}, you may not want package
924 build processes themselves to run as @code{root} too, for obvious
925 security reasons. To avoid that, a special pool of @dfn{build users}
926 should be created for use by build processes started by the daemon.
927 These build users need not have a shell and a home directory: they will
928 just be used when the daemon drops @code{root} privileges in build
929 processes. Having several such users allows the daemon to launch
930 distinct build processes under separate UIDs, which guarantees that they
931 do not interfere with each other---an essential feature since builds are
932 regarded as pure functions (@pxref{Introduction}).
934 On a GNU/Linux system, a build user pool may be created like this (using
935 Bash syntax and the @code{shadow} commands):
937 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
938 @c for why `-G' is needed.
940 # groupadd --system guixbuild
941 # for i in `seq -w 1 10`;
943 useradd -g guixbuild -G guixbuild \
944 -d /var/empty -s `which nologin` \
945 -c "Guix build user $i" --system \
951 The number of build users determines how many build jobs may run in
952 parallel, as specified by the @option{--max-jobs} option
953 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
954 @command{guix system vm} and related commands, you may need to add the
955 build users to the @code{kvm} group so they can access @file{/dev/kvm},
956 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
957 (@pxref{Invoking guix system}).
959 The @code{guix-daemon} program may then be run as @code{root} with the
960 following command@footnote{If your machine uses the systemd init system,
961 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
962 file in @file{/etc/systemd/system} will ensure that
963 @command{guix-daemon} is automatically started. Similarly, if your
964 machine uses the Upstart init system, drop the
965 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
966 file in @file{/etc/init}.}:
969 # guix-daemon --build-users-group=guixbuild
974 This way, the daemon starts build processes in a chroot, under one of
975 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
976 environment contains nothing but:
978 @c Keep this list in sync with libstore/build.cc! -----------------------
981 a minimal @code{/dev} directory, created mostly independently from the
982 host @code{/dev}@footnote{``Mostly'', because while the set of files
983 that appear in the chroot's @code{/dev} is fixed, most of these files
984 can only be created if the host has them.};
987 the @code{/proc} directory; it only shows the processes of the container
988 since a separate PID name space is used;
991 @file{/etc/passwd} with an entry for the current user and an entry for
995 @file{/etc/group} with an entry for the user's group;
998 @file{/etc/hosts} with an entry that maps @code{localhost} to
1002 a writable @file{/tmp} directory.
1005 You can influence the directory where the daemon stores build trees
1006 @i{via} the @code{TMPDIR} environment variable. However, the build tree
1007 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1008 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1009 This way, the value of @code{TMPDIR} does not leak inside build
1010 environments, which avoids discrepancies in cases where build processes
1011 capture the name of their build tree.
1014 The daemon also honors the @code{http_proxy} environment variable for
1015 HTTP downloads it performs, be it for fixed-output derivations
1016 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1018 If you are installing Guix as an unprivileged user, it is still possible
1019 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1020 However, build processes will not be isolated from one another, and not
1021 from the rest of the system. Thus, build processes may interfere with
1022 each other, and may access programs, libraries, and other files
1023 available on the system---making it much harder to view them as
1024 @emph{pure} functions.
1027 @node Daemon Offload Setup
1028 @subsection Using the Offload Facility
1032 When desired, the build daemon can @dfn{offload} derivation builds to
1033 other machines running Guix, using the @code{offload} @dfn{build
1034 hook}@footnote{This feature is available only when
1035 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1036 present.}. When that
1037 feature is enabled, a list of user-specified build machines is read from
1038 @file{/etc/guix/machines.scm}; every time a build is requested, for
1039 instance via @code{guix build}, the daemon attempts to offload it to one
1040 of the machines that satisfy the constraints of the derivation, in
1041 particular its system type---e.g., @file{x86_64-linux}. Missing
1042 prerequisites for the build are copied over SSH to the target machine,
1043 which then proceeds with the build; upon success the output(s) of the
1044 build are copied back to the initial machine.
1046 The @file{/etc/guix/machines.scm} file typically looks like this:
1049 (list (build-machine
1050 (name "eightysix.example.org")
1051 (system "x86_64-linux")
1052 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1054 (speed 2.)) ;incredibly fast!
1057 (name "meeps.example.org")
1058 (system "mips64el-linux")
1059 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1062 (string-append (getenv "HOME")
1063 "/.ssh/identity-for-guix"))))
1067 In the example above we specify a list of two build machines, one for
1068 the @code{x86_64} architecture and one for the @code{mips64el}
1071 In fact, this file is---not surprisingly!---a Scheme file that is
1072 evaluated when the @code{offload} hook is started. Its return value
1073 must be a list of @code{build-machine} objects. While this example
1074 shows a fixed list of build machines, one could imagine, say, using
1075 DNS-SD to return a list of potential build machines discovered in the
1076 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1077 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1080 @deftp {Data Type} build-machine
1081 This data type represents build machines to which the daemon may offload
1082 builds. The important fields are:
1087 The host name of the remote machine.
1090 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1093 The user account to use when connecting to the remote machine over SSH.
1094 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1095 allow non-interactive logins.
1098 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1099 This is used to authenticate the machine when we connect to it. It is a
1100 long string that looks like this:
1103 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1106 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1107 key can be found in a file such as
1108 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1110 If the machine is running the SSH daemon of GNU@tie{}lsh,
1111 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1112 similar file. It can be converted to the OpenSSH format using
1113 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1116 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1117 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1122 A number of optional fields may be specified:
1126 @item @code{port} (default: @code{22})
1127 Port number of SSH server on the machine.
1129 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1130 The SSH private key file to use when connecting to the machine, in
1131 OpenSSH format. This key must not be protected with a passphrase.
1133 Note that the default value is the private key @emph{of the root
1134 account}. Make sure it exists if you use the default.
1136 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1137 @itemx @code{compression-level} (default: @code{3})
1138 The SSH-level compression methods and compression level requested.
1140 Note that offloading relies on SSH compression to reduce bandwidth usage
1141 when transferring files to and from build machines.
1143 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1144 File name of the Unix-domain socket @command{guix-daemon} is listening
1147 @item @code{parallel-builds} (default: @code{1})
1148 The number of builds that may run in parallel on the machine.
1150 @item @code{speed} (default: @code{1.0})
1151 A ``relative speed factor''. The offload scheduler will tend to prefer
1152 machines with a higher speed factor.
1154 @item @code{features} (default: @code{'()})
1155 A list of strings denoting specific features supported by the machine.
1156 An example is @code{"kvm"} for machines that have the KVM Linux modules
1157 and corresponding hardware support. Derivations can request features by
1158 name, and they will be scheduled on matching build machines.
1163 The @command{guix} command must be in the search path on the build
1164 machines. You can check whether this is the case by running:
1167 ssh build-machine guix repl --version
1170 There is one last thing to do once @file{machines.scm} is in place. As
1171 explained above, when offloading, files are transferred back and forth
1172 between the machine stores. For this to work, you first need to
1173 generate a key pair on each machine to allow the daemon to export signed
1174 archives of files from the store (@pxref{Invoking guix archive}):
1177 # guix archive --generate-key
1181 Each build machine must authorize the key of the master machine so that
1182 it accepts store items it receives from the master:
1185 # guix archive --authorize < master-public-key.txt
1189 Likewise, the master machine must authorize the key of each build machine.
1191 All the fuss with keys is here to express pairwise mutual trust
1192 relations between the master and the build machines. Concretely, when
1193 the master receives files from a build machine (and @i{vice versa}), its
1194 build daemon can make sure they are genuine, have not been tampered
1195 with, and that they are signed by an authorized key.
1197 @cindex offload test
1198 To test whether your setup is operational, run this command on the
1205 This will attempt to connect to each of the build machines specified in
1206 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1207 available on each machine, attempt to export to the machine and import
1208 from it, and report any error in the process.
1210 If you want to test a different machine file, just specify it on the
1214 # guix offload test machines-qualif.scm
1217 Last, you can test the subset of the machines whose name matches a
1218 regular expression like this:
1221 # guix offload test machines.scm '\.gnu\.org$'
1224 @cindex offload status
1225 To display the current load of all build hosts, run this command on the
1229 # guix offload status
1233 @node SELinux Support
1234 @subsection SELinux Support
1236 @cindex SELinux, daemon policy
1237 @cindex mandatory access control, SELinux
1238 @cindex security, guix-daemon
1239 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1240 can be installed on a system where SELinux is enabled, in order to label
1241 Guix files and to specify the expected behavior of the daemon. Since
1242 Guix System does not provide an SELinux base policy, the daemon policy cannot
1243 be used on Guix System.
1245 @subsubsection Installing the SELinux policy
1246 @cindex SELinux, policy installation
1247 To install the policy run this command as root:
1250 semodule -i etc/guix-daemon.cil
1253 Then relabel the file system with @code{restorecon} or by a different
1254 mechanism provided by your system.
1256 Once the policy is installed, the file system has been relabeled, and
1257 the daemon has been restarted, it should be running in the
1258 @code{guix_daemon_t} context. You can confirm this with the following
1262 ps -Zax | grep guix-daemon
1265 Monitor the SELinux log files as you run a command like @code{guix build
1266 hello} to convince yourself that SELinux permits all necessary
1269 @subsubsection Limitations
1270 @cindex SELinux, limitations
1272 This policy is not perfect. Here is a list of limitations or quirks
1273 that should be considered when deploying the provided SELinux policy for
1278 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1279 operations involve contexts that have anything to do with
1280 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1281 but it would be preferrable to define socket rules for only this label.
1284 @code{guix gc} cannot access arbitrary links to profiles. By design,
1285 the file label of the destination of a symlink is independent of the
1286 file label of the link itself. Although all profiles under
1287 $localstatedir are labelled, the links to these profiles inherit the
1288 label of the directory they are in. For links in the user’s home
1289 directory this will be @code{user_home_t}. But for links from the root
1290 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1291 directory, etc, this won’t work. @code{guix gc} would be prevented from
1292 reading and following these links.
1295 The daemon’s feature to listen for TCP connections might no longer work.
1296 This might require extra rules, because SELinux treats network sockets
1297 differently from files.
1300 Currently all files with a name matching the regular expression
1301 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1302 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1303 that name in any profile would be permitted to run in the
1304 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1305 build a package that provides this executable and convince a user to
1306 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1307 At that point SELinux could not prevent it from accessing files that are
1308 allowed for processes in that domain.
1310 We could generate a much more restrictive policy at installation time,
1311 so that only the @emph{exact} file name of the currently installed
1312 @code{guix-daemon} executable would be labelled with
1313 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1314 The downside is that root would have to install or upgrade the policy at
1315 installation time whenever the Guix package that provides the
1316 effectively running @code{guix-daemon} executable is upgraded.
1319 @node Invoking guix-daemon
1320 @section Invoking @command{guix-daemon}
1322 The @command{guix-daemon} program implements all the functionality to
1323 access the store. This includes launching build processes, running the
1324 garbage collector, querying the availability of a build result, etc. It
1325 is normally run as @code{root} like this:
1328 # guix-daemon --build-users-group=guixbuild
1332 For details on how to set it up, @pxref{Setting Up the Daemon}.
1335 @cindex container, build environment
1336 @cindex build environment
1337 @cindex reproducible builds
1338 By default, @command{guix-daemon} launches build processes under
1339 different UIDs, taken from the build group specified with
1340 @code{--build-users-group}. In addition, each build process is run in a
1341 chroot environment that only contains the subset of the store that the
1342 build process depends on, as specified by its derivation
1343 (@pxref{Programming Interface, derivation}), plus a set of specific
1344 system directories. By default, the latter contains @file{/dev} and
1345 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1346 @dfn{container}: in addition to having its own file system tree, it has
1347 a separate mount name space, its own PID name space, network name space,
1348 etc. This helps achieve reproducible builds (@pxref{Features}).
1350 When the daemon performs a build on behalf of the user, it creates a
1351 build directory under @file{/tmp} or under the directory specified by
1352 its @code{TMPDIR} environment variable. This directory is shared with
1353 the container for the duration of the build, though within the container,
1354 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1356 The build directory is automatically deleted upon completion, unless the
1357 build failed and the client specified @option{--keep-failed}
1358 (@pxref{Invoking guix build, @option{--keep-failed}}).
1360 The daemon listens for connections and spawns one sub-process for each session
1361 started by a client (one of the @command{guix} sub-commands.) The
1362 @command{guix processes} command allows you to get an overview of the activity
1363 on your system by viewing each of the active sessions and clients.
1364 @xref{Invoking guix processes}, for more information.
1366 The following command-line options are supported:
1369 @item --build-users-group=@var{group}
1370 Take users from @var{group} to run build processes (@pxref{Setting Up
1371 the Daemon, build users}).
1373 @item --no-substitutes
1375 Do not use substitutes for build products. That is, always build things
1376 locally instead of allowing downloads of pre-built binaries
1377 (@pxref{Substitutes}).
1379 When the daemon runs with @code{--no-substitutes}, clients can still
1380 explicitly enable substitution @i{via} the @code{set-build-options}
1381 remote procedure call (@pxref{The Store}).
1383 @item --substitute-urls=@var{urls}
1384 @anchor{daemon-substitute-urls}
1385 Consider @var{urls} the default whitespace-separated list of substitute
1386 source URLs. When this option is omitted,
1387 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1389 This means that substitutes may be downloaded from @var{urls}, as long
1390 as they are signed by a trusted signature (@pxref{Substitutes}).
1394 Do not use offload builds to other machines (@pxref{Daemon Offload
1395 Setup}). That is, always build things locally instead of offloading
1396 builds to remote machines.
1398 @item --cache-failures
1399 Cache build failures. By default, only successful builds are cached.
1401 When this option is used, @command{guix gc --list-failures} can be used
1402 to query the set of store items marked as failed; @command{guix gc
1403 --clear-failures} removes store items from the set of cached failures.
1404 @xref{Invoking guix gc}.
1406 @item --cores=@var{n}
1408 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1411 The default value is @code{0}, but it may be overridden by clients, such
1412 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1415 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1416 in the build process, which can then use it to exploit internal
1417 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1419 @item --max-jobs=@var{n}
1421 Allow at most @var{n} build jobs in parallel. The default value is
1422 @code{1}. Setting it to @code{0} means that no builds will be performed
1423 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1424 Setup}), or simply fail.
1426 @item --max-silent-time=@var{seconds}
1427 When the build or substitution process remains silent for more than
1428 @var{seconds}, terminate it and report a build failure.
1430 The default value is @code{0}, which disables the timeout.
1432 The value specified here can be overridden by clients (@pxref{Common
1433 Build Options, @code{--max-silent-time}}).
1435 @item --timeout=@var{seconds}
1436 Likewise, when the build or substitution process lasts for more than
1437 @var{seconds}, terminate it and report a build failure.
1439 The default value is @code{0}, which disables the timeout.
1441 The value specified here can be overridden by clients (@pxref{Common
1442 Build Options, @code{--timeout}}).
1444 @item --rounds=@var{N}
1445 Build each derivation @var{n} times in a row, and raise an error if
1446 consecutive build results are not bit-for-bit identical. Note that this
1447 setting can be overridden by clients such as @command{guix build}
1448 (@pxref{Invoking guix build}).
1450 When used in conjunction with @option{--keep-failed}, the differing
1451 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1452 This makes it easy to look for differences between the two results.
1455 Produce debugging output.
1457 This is useful to debug daemon start-up issues, but then it may be
1458 overridden by clients, for example the @code{--verbosity} option of
1459 @command{guix build} (@pxref{Invoking guix build}).
1461 @item --chroot-directory=@var{dir}
1462 Add @var{dir} to the build chroot.
1464 Doing this may change the result of build processes---for instance if
1465 they use optional dependencies found in @var{dir} when it is available,
1466 and not otherwise. For that reason, it is not recommended to do so.
1467 Instead, make sure that each derivation declares all the inputs that it
1470 @item --disable-chroot
1471 Disable chroot builds.
1473 Using this option is not recommended since, again, it would allow build
1474 processes to gain access to undeclared dependencies. It is necessary,
1475 though, when @command{guix-daemon} is running under an unprivileged user
1478 @item --log-compression=@var{type}
1479 Compress build logs according to @var{type}, one of @code{gzip},
1480 @code{bzip2}, or @code{none}.
1482 Unless @code{--lose-logs} is used, all the build logs are kept in the
1483 @var{localstatedir}. To save space, the daemon automatically compresses
1484 them with bzip2 by default.
1486 @item --disable-deduplication
1487 @cindex deduplication
1488 Disable automatic file ``deduplication'' in the store.
1490 By default, files added to the store are automatically ``deduplicated'':
1491 if a newly added file is identical to another one found in the store,
1492 the daemon makes the new file a hard link to the other file. This can
1493 noticeably reduce disk usage, at the expense of slightly increased
1494 input/output load at the end of a build process. This option disables
1497 @item --gc-keep-outputs[=yes|no]
1498 Tell whether the garbage collector (GC) must keep outputs of live
1502 @cindex garbage collector roots
1503 When set to ``yes'', the GC will keep the outputs of any live derivation
1504 available in the store---the @code{.drv} files. The default is ``no'',
1505 meaning that derivation outputs are kept only if they are reachable from a GC
1506 root. @xref{Invoking guix gc}, for more on GC roots.
1508 @item --gc-keep-derivations[=yes|no]
1509 Tell whether the garbage collector (GC) must keep derivations
1510 corresponding to live outputs.
1512 When set to ``yes'', as is the case by default, the GC keeps
1513 derivations---i.e., @code{.drv} files---as long as at least one of their
1514 outputs is live. This allows users to keep track of the origins of
1515 items in their store. Setting it to ``no'' saves a bit of disk space.
1517 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1518 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1519 ``yes'' causes liveness to flow from derivations to outputs. When both are
1520 set to ``yes'', the effect is to keep all the build prerequisites (the
1521 sources, compiler, libraries, and other build-time tools) of live objects in
1522 the store, regardless of whether these prerequisites are reachable from a GC
1523 root. This is convenient for developers since it saves rebuilds or downloads.
1525 @item --impersonate-linux-2.6
1526 On Linux-based systems, impersonate Linux 2.6. This means that the
1527 kernel's @code{uname} system call will report 2.6 as the release number.
1529 This might be helpful to build programs that (usually wrongfully) depend
1530 on the kernel version number.
1533 Do not keep build logs. By default they are kept under
1534 @code{@var{localstatedir}/guix/log}.
1536 @item --system=@var{system}
1537 Assume @var{system} as the current system type. By default it is the
1538 architecture/kernel pair found at configure time, such as
1539 @code{x86_64-linux}.
1541 @item --listen=@var{endpoint}
1542 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1543 as the file name of a Unix-domain socket if it starts with
1544 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1545 host name or host name and port to listen to. Here are a few examples:
1548 @item --listen=/gnu/var/daemon
1549 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1550 creating it if needed.
1552 @item --listen=localhost
1553 @cindex daemon, remote access
1554 @cindex remote access to the daemon
1555 @cindex daemon, cluster setup
1556 @cindex clusters, daemon setup
1557 Listen for TCP connections on the network interface corresponding to
1558 @code{localhost}, on port 44146.
1560 @item --listen=128.0.0.42:1234
1561 Listen for TCP connections on the network interface corresponding to
1562 @code{128.0.0.42}, on port 1234.
1565 This option can be repeated multiple times, in which case
1566 @command{guix-daemon} accepts connections on all the specified
1567 endpoints. Users can tell client commands what endpoint to connect to
1568 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1569 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1572 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1573 @code{--listen=@var{host}} is suitable on local networks, such as
1574 clusters, where only trusted nodes may connect to the build daemon. In
1575 other cases where remote access to the daemon is needed, we recommend
1576 using Unix-domain sockets along with SSH.
1579 When @code{--listen} is omitted, @command{guix-daemon} listens for
1580 connections on the Unix-domain socket located at
1581 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1585 @node Application Setup
1586 @section Application Setup
1588 @cindex foreign distro
1589 When using Guix on top of GNU/Linux distribution other than Guix System---a
1590 so-called @dfn{foreign distro}---a few additional steps are needed to
1591 get everything in place. Here are some of them.
1595 @anchor{locales-and-locpath}
1596 @cindex locales, when not on Guix System
1598 @vindex GUIX_LOCPATH
1599 Packages installed @i{via} Guix will not use the locale data of the
1600 host system. Instead, you must first install one of the locale packages
1601 available with Guix and then define the @code{GUIX_LOCPATH} environment
1605 $ guix install glibc-locales
1606 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1609 Note that the @code{glibc-locales} package contains data for all the
1610 locales supported by the GNU@tie{}libc and weighs in at around
1611 917@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1612 limited to a few UTF-8 locales.
1614 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1615 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1616 Manual}). There are two important differences though:
1620 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1621 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1622 to make sure the programs of the foreign distro will not end up loading
1623 incompatible locale data.
1626 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1627 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1628 should your Guix profile contain a mixture of programs linked against
1629 different libc version, each libc version will only try to load locale
1630 data in the right format.
1633 This is important because the locale data format used by different libc
1634 versions may be incompatible.
1636 @subsection Name Service Switch
1638 @cindex name service switch, glibc
1639 @cindex NSS (name service switch), glibc
1640 @cindex nscd (name service caching daemon)
1641 @cindex name service caching daemon (nscd)
1642 When using Guix on a foreign distro, we @emph{strongly recommend} that
1643 the system run the GNU C library's @dfn{name service cache daemon},
1644 @command{nscd}, which should be listening on the
1645 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1646 installed with Guix may fail to look up host names or user accounts, or
1647 may even crash. The next paragraphs explain why.
1649 @cindex @file{nsswitch.conf}
1650 The GNU C library implements a @dfn{name service switch} (NSS), which is
1651 an extensible mechanism for ``name lookups'' in general: host name
1652 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1653 The GNU C Library Reference Manual}).
1655 @cindex Network information service (NIS)
1656 @cindex NIS (Network information service)
1657 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1658 lookup implementations: for example, the @code{nss-mdns} plugin allow
1659 resolution of @code{.local} host names, the @code{nis} plugin allows
1660 user account lookup using the Network information service (NIS), and so
1661 on. These extra ``lookup services'' are configured system-wide in
1662 @file{/etc/nsswitch.conf}, and all the programs running on the system
1663 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1666 When they perform a name lookup---for instance by calling the
1667 @code{getaddrinfo} function in C---applications first try to connect to
1668 the nscd; on success, nscd performs name lookups on their behalf. If
1669 the nscd is not running, then they perform the name lookup by
1670 themselves, by loading the name lookup services into their own address
1671 space and running it. These name lookup services---the
1672 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1673 the host system's C library, rather than from the C library the
1674 application is linked against (the C library coming from Guix).
1676 And this is where the problem is: if your application is linked against
1677 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1678 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1679 likely crash or have its name lookups fail unexpectedly.
1681 Running @command{nscd} on the system, among other advantages, eliminates
1682 this binary incompatibility problem because those @code{libnss_*.so}
1683 files are loaded in the @command{nscd} process, not in applications
1686 @subsection X11 Fonts
1689 The majority of graphical applications use Fontconfig to locate and
1690 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1691 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1692 by default. Thus, to allow graphical applications installed with Guix
1693 to display fonts, you have to install fonts with Guix as well.
1694 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1695 @code{font-gnu-freefont}.
1697 @cindex @code{fc-cache}
1699 Once you have installed or removed fonts, or when you notice an
1700 application that does not find fonts, you may need to install Fontconfig
1701 and to force an update of its font cache by running:
1704 guix install fontconfig
1708 To display text written in Chinese languages, Japanese, or Korean in
1709 graphical applications, consider installing
1710 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1711 has multiple outputs, one per language family (@pxref{Packages with
1712 Multiple Outputs}). For instance, the following command installs fonts
1713 for Chinese languages:
1716 guix install font-adobe-source-han-sans:cn
1719 @cindex @code{xterm}
1720 Older programs such as @command{xterm} do not use Fontconfig and instead
1721 rely on server-side font rendering. Such programs require to specify a
1722 full name of a font using XLFD (X Logical Font Description), like this:
1725 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1728 To be able to use such full names for the TrueType fonts installed in
1729 your Guix profile, you need to extend the font path of the X server:
1731 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1732 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1734 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1737 @cindex @code{xlsfonts}
1738 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1739 to make sure your TrueType fonts are listed there.
1742 @subsection X.509 Certificates
1744 @cindex @code{nss-certs}
1745 The @code{nss-certs} package provides X.509 certificates, which allow
1746 programs to authenticate Web servers accessed over HTTPS.
1748 When using Guix on a foreign distro, you can install this package and
1749 define the relevant environment variables so that packages know where to
1750 look for certificates. @xref{X.509 Certificates}, for detailed
1753 @subsection Emacs Packages
1755 @cindex @code{emacs}
1756 When you install Emacs packages with Guix, the Elisp files are placed
1757 under the @file{share/emacs/site-lisp/} directory of the profile in
1758 which they are installed. The Elisp libraries are made available to
1759 Emacs through the @code{EMACSLOADPATH} environment variable, which is
1760 set when installing Emacs itself.
1762 Additionally, autoload definitions are automatically evaluated at the
1763 initialization of Emacs, by the Guix-specific
1764 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1765 want to avoid auto-loading the Emacs packages installed with Guix, you
1766 can do so by running Emacs with the @code{--no-site-file} option
1767 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1769 @subsection The GCC toolchain
1771 @c XXX: The contents of this section were moved under
1772 @c ``Development'', since it makes more sense there and is not specific
1773 @c foreign distros. Remove it from here eventually?
1774 @xref{Packages for C Development}, for information on packages for C/C++
1777 @node Upgrading Guix
1778 @section Upgrading Guix
1780 @cindex Upgrading Guix, on a foreign distro
1782 To upgrade Guix, run:
1788 @xref{Invoking guix pull}, for more information.
1790 @cindex upgrading Guix for the root user, on a foreign distro
1791 @cindex upgrading the Guix daemon, on a foreign distro
1792 @cindex @command{guix pull} for the root user, on a foreign distro
1794 On a foreign distro, you can upgrade the build daemon by running:
1801 followed by (assuming your distro uses the systemd service management
1805 systemctl restart guix-daemon.service
1808 On Guix System, upgrading the daemon is achieved by reconfiguring the
1809 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1813 @c *********************************************************************
1814 @node System Installation
1815 @chapter System Installation
1817 @cindex installing Guix System
1818 @cindex Guix System, installation
1819 This section explains how to install Guix System
1820 on a machine. Guix, as a package manager, can
1821 also be installed on top of a running GNU/Linux system,
1822 @pxref{Installation}.
1826 @c This paragraph is for people reading this from tty2 of the
1827 @c installation image.
1828 You are reading this documentation with an Info reader. For details on
1829 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1830 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1831 Info}. Hit @kbd{l} afterwards to come back here.
1833 Alternately, run @command{info info} in another tty to keep the manual
1839 * Limitations:: What you can expect.
1840 * Hardware Considerations:: Supported hardware.
1841 * USB Stick and DVD Installation:: Preparing the installation medium.
1842 * Preparing for Installation:: Networking, partitioning, etc.
1843 * Guided Graphical Installation:: Easy graphical installation.
1844 * Manual Installation:: Manual installation for wizards.
1845 * After System Installation:: When installation succeeded.
1846 * Installing Guix in a VM:: Guix System playground.
1847 * Building the Installation Image:: How this comes to be.
1851 @section Limitations
1853 We consider Guix System to be ready for a wide range of ``desktop'' and server
1854 use cases. The reliability guarantees it provides---transactional upgrades
1855 and rollbacks, reproducibility---make it a solid foundation.
1857 Nevertheless, before you proceed with the installation, be aware of the
1858 following noteworthy limitations applicable to version @value{VERSION}:
1862 Support for the Logical Volume Manager (LVM) is missing.
1865 More and more system services are provided (@pxref{Services}), but some
1869 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1870 as well as a number of X11 window managers. However, KDE is currently
1874 More than a disclaimer, this is an invitation to report issues (and success
1875 stories!), and to join us in improving it. @xref{Contributing}, for more
1879 @node Hardware Considerations
1880 @section Hardware Considerations
1882 @cindex hardware support on Guix System
1883 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1884 builds around the kernel Linux-libre, which means that only hardware for
1885 which free software drivers and firmware exist is supported. Nowadays,
1886 a wide range of off-the-shelf hardware is supported on
1887 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1888 Ethernet controllers. Unfortunately, there are still areas where
1889 hardware vendors deny users control over their own computing, and such
1890 hardware is not supported on Guix System.
1892 @cindex WiFi, hardware support
1893 One of the main areas where free drivers or firmware are lacking is WiFi
1894 devices. WiFi devices known to work include those using Atheros chips
1895 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1896 driver, and those using Broadcom/AirForce chips (BCM43xx with
1897 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1898 Linux-libre driver. Free firmware exists for both and is available
1899 out-of-the-box on Guix System, as part of @code{%base-firmware}
1900 (@pxref{operating-system Reference, @code{firmware}}).
1902 @cindex RYF, Respects Your Freedom
1903 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1904 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1905 certification program for hardware products that respect your freedom
1906 and your privacy and ensure that you have control over your device. We
1907 encourage you to check the list of RYF-certified devices.
1909 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1910 web site. It contains a catalog of hardware devices with information
1911 about their support in GNU/Linux.
1914 @node USB Stick and DVD Installation
1915 @section USB Stick and DVD Installation
1917 An ISO-9660 installation image that can be written to a USB stick or
1918 burnt to a DVD can be downloaded from
1919 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1920 where @var{system} is one of:
1924 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1927 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1930 @c start duplication of authentication part from ``Binary Installation''
1931 Make sure to download the associated @file{.sig} file and to verify the
1932 authenticity of the image against it, along these lines:
1935 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1936 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1939 If that command fails because you do not have the required public key,
1940 then run this command to import it:
1943 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1944 -qO - | gpg --import -
1948 and rerun the @code{gpg --verify} command.
1950 Take note that a warning like ``This key is not certified with a trusted
1951 signature!'' is normal.
1955 This image contains the tools necessary for an installation.
1956 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1958 @unnumberedsubsec Copying to a USB Stick
1960 To copy the image to a USB stick, follow these steps:
1964 Decompress the image using the @command{xz} command:
1967 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1971 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1972 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1973 copy the image with:
1976 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1980 Access to @file{/dev/sdX} usually requires root privileges.
1983 @unnumberedsubsec Burning on a DVD
1985 To copy the image to a DVD, follow these steps:
1989 Decompress the image using the @command{xz} command:
1992 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1996 Insert a blank DVD into your machine, and determine
1997 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
1998 copy the image with:
2001 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
2004 Access to @file{/dev/srX} usually requires root privileges.
2007 @unnumberedsubsec Booting
2009 Once this is done, you should be able to reboot the system and boot from
2010 the USB stick or DVD. The latter usually requires you to get in the
2011 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2012 In order to boot from Libreboot, switch to the command mode by pressing
2013 the @kbd{c} key and type @command{search_grub usb}.
2015 @xref{Installing Guix in a VM}, if, instead, you would like to install
2016 Guix System in a virtual machine (VM).
2019 @node Preparing for Installation
2020 @section Preparing for Installation
2022 Once you have booted, you can use the guided graphical installer, which makes
2023 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
2024 if you are already familiar with GNU/Linux and if you want more control than
2025 what the graphical installer provides, you can choose the ``manual''
2026 installation process (@pxref{Manual Installation}).
2028 The graphical installer is available on TTY1. You can obtain root shells on
2029 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2030 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2031 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2032 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2033 which allows you to select text with the left mouse button and to paste it
2034 with the middle button.
2037 Installation requires access to the Internet so that any missing
2038 dependencies of your system configuration can be downloaded. See the
2039 ``Networking'' section below.
2042 @node Guided Graphical Installation
2043 @section Guided Graphical Installation
2045 The graphical installer is a text-based user interface. It will guide you,
2046 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2048 The first dialog boxes allow you to set up the system as you use it during the
2049 installation: you can choose the language, keyboard layout, and set up
2050 networking, which will be used during the installation. The image below shows
2051 the networking dialog.
2053 @image{images/installer-network,5in,, networking setup with the graphical installer}
2055 Later steps allow you to partition your hard disk, as shown in the image
2056 below, to choose whether or not to use encrypted file systems, to enter the
2057 host name and root password, and to create an additional account, among other
2060 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2062 Note that, at any time, the installer allows you to exit the current
2063 installation step and resume at a previous step, as show in the image below.
2065 @image{images/installer-resume,5in,, resuming the installation process}
2067 Once you're done, the installer produces an operating system configuration and
2068 displays it (@pxref{Using the Configuration System}). At that point you can
2069 hit ``OK'' and installation will proceed. On success, you can reboot into the
2070 new system and enjoy. @xref{After System Installation}, for what's next!
2073 @node Manual Installation
2074 @section Manual Installation
2076 This section describes how you would ``manually'' install GNU@tie{}Guix System
2077 on your machine. This option requires familiarity with GNU/Linux, with the
2078 shell, and with common administration tools. If you think this is not for
2079 you, consider using the guided graphical installer (@pxref{Guided Graphical
2082 The installation system provides root shells on TTYs 3 to 6; press
2083 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2084 many common tools needed to install the system. But it is also a full-blown
2085 Guix System, which means that you can install additional packages, should you
2086 need it, using @command{guix package} (@pxref{Invoking guix package}).
2089 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2090 * Proceeding with the Installation:: Installing.
2093 @node Keyboard Layout and Networking and Partitioning
2094 @subsection Keyboard Layout, Networking, and Partitioning
2096 Before you can install the system, you may want to adjust the keyboard layout,
2097 set up networking, and partition your target hard disk. This section will
2098 guide you through this.
2100 @subsubsection Keyboard Layout
2102 @cindex keyboard layout
2103 The installation image uses the US qwerty keyboard layout. If you want
2104 to change it, you can use the @command{loadkeys} command. For example,
2105 the following command selects the Dvorak keyboard layout:
2111 See the files under @file{/run/current-system/profile/share/keymaps} for
2112 a list of available keyboard layouts. Run @command{man loadkeys} for
2115 @subsubsection Networking
2117 Run the following command to see what your network interfaces are called:
2124 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2130 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2131 Wired interfaces have a name starting with @samp{e}; for example, the
2132 interface corresponding to the first on-board Ethernet controller is
2133 called @samp{eno1}. Wireless interfaces have a name starting with
2134 @samp{w}, like @samp{w1p2s0}.
2137 @item Wired connection
2138 To configure a wired network run the following command, substituting
2139 @var{interface} with the name of the wired interface you want to use.
2142 ifconfig @var{interface} up
2146 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2149 ip link set @var{interface} up
2152 @item Wireless connection
2155 To configure wireless networking, you can create a configuration file
2156 for the @command{wpa_supplicant} configuration tool (its location is not
2157 important) using one of the available text editors such as
2161 nano wpa_supplicant.conf
2164 As an example, the following stanza can go to this file and will work
2165 for many wireless networks, provided you give the actual SSID and
2166 passphrase for the network you are connecting to:
2170 ssid="@var{my-ssid}"
2172 psk="the network's secret passphrase"
2176 Start the wireless service and run it in the background with the
2177 following command (substitute @var{interface} with the name of the
2178 network interface you want to use):
2181 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2184 Run @command{man wpa_supplicant} for more information.
2188 At this point, you need to acquire an IP address. On a network where IP
2189 addresses are automatically assigned @i{via} DHCP, you can run:
2192 dhclient -v @var{interface}
2195 Try to ping a server to see if networking is up and running:
2201 Setting up network access is almost always a requirement because the
2202 image does not contain all the software and tools that may be needed.
2204 @cindex proxy, during system installation
2205 If you need HTTP and HTTPS access to go through a proxy, run the
2209 herd set-http-proxy guix-daemon @var{URL}
2213 where @var{URL} is the proxy URL, for example
2214 @code{http://example.org:8118}.
2216 @cindex installing over SSH
2217 If you want to, you can continue the installation remotely by starting
2221 herd start ssh-daemon
2224 Make sure to either set a password with @command{passwd}, or configure
2225 OpenSSH public key authentication before logging in.
2227 @subsubsection Disk Partitioning
2229 Unless this has already been done, the next step is to partition, and
2230 then format the target partition(s).
2232 The installation image includes several partitioning tools, including
2233 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2234 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2235 the partition layout you want:
2241 If your disk uses the GUID Partition Table (GPT) format and you plan to
2242 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2243 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2246 @cindex EFI, installation
2247 @cindex UEFI, installation
2248 @cindex ESP, EFI system partition
2249 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2250 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2251 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2254 parted /dev/sda set 1 esp on
2258 @vindex grub-bootloader
2259 @vindex grub-efi-bootloader
2260 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2261 @file{/sys/firmware/efi} exists in the installation image, then you should
2262 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2263 Otherwise you should use the BIOS-based GRUB, known as
2264 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2268 Once you are done partitioning the target hard disk drive, you have to
2269 create a file system on the relevant partition(s)@footnote{Currently
2270 Guix System only supports ext4, btrfs, and JFS file systems. In particular,
2271 code that reads file system UUIDs and labels only works for these file system
2272 types.}. For the ESP, if you have one and assuming it is
2273 @file{/dev/sda1}, run:
2276 mkfs.fat -F32 /dev/sda1
2279 Preferably, assign file systems a label so that you can easily and
2280 reliably refer to them in @code{file-system} declarations (@pxref{File
2281 Systems}). This is typically done using the @code{-L} option of
2282 @command{mkfs.ext4} and related commands. So, assuming the target root
2283 partition lives at @file{/dev/sda2}, a file system with the label
2284 @code{my-root} can be created with:
2287 mkfs.ext4 -L my-root /dev/sda2
2290 @cindex encrypted disk
2291 If you are instead planning to encrypt the root partition, you can use
2292 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2293 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2294 @code{man cryptsetup}} for more information.) Assuming you want to
2295 store the root partition on @file{/dev/sda2}, the command sequence would
2296 be along these lines:
2299 cryptsetup luksFormat /dev/sda2
2300 cryptsetup open --type luks /dev/sda2 my-partition
2301 mkfs.ext4 -L my-root /dev/mapper/my-partition
2304 Once that is done, mount the target file system under @file{/mnt}
2305 with a command like (again, assuming @code{my-root} is the label of the
2309 mount LABEL=my-root /mnt
2312 Also mount any other file systems you would like to use on the target
2313 system relative to this path. If you have opted for @file{/boot/efi} as an
2314 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2315 found by @code{guix system init} afterwards.
2317 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2318 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2319 sure to initialize them with @command{mkswap}. Assuming you have one
2320 swap partition on @file{/dev/sda3}, you would run:
2327 Alternatively, you may use a swap file. For example, assuming that in
2328 the new system you want to use the file @file{/swapfile} as a swap file,
2329 you would run@footnote{This example will work for many types of file
2330 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2331 btrfs), the required steps may be different. For details, see the
2332 manual pages for @command{mkswap} and @command{swapon}.}:
2335 # This is 10 GiB of swap space. Adjust "count" to change the size.
2336 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2337 # For security, make the file readable and writable only by root.
2338 chmod 600 /mnt/swapfile
2339 mkswap /mnt/swapfile
2340 swapon /mnt/swapfile
2343 Note that if you have encrypted the root partition and created a swap
2344 file in its file system as described above, then the encryption also
2345 protects the swap file, just like any other file in that file system.
2347 @node Proceeding with the Installation
2348 @subsection Proceeding with the Installation
2350 With the target partitions ready and the target root mounted on
2351 @file{/mnt}, we're ready to go. First, run:
2354 herd start cow-store /mnt
2357 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2358 during the installation phase are written to the target disk on @file{/mnt}
2359 rather than kept in memory. This is necessary because the first phase of
2360 the @command{guix system init} command (see below) entails downloads or
2361 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2363 Next, you have to edit a file and
2364 provide the declaration of the operating system to be installed. To
2365 that end, the installation system comes with three text editors. We
2366 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2367 supports syntax highlighting and parentheses matching; other editors
2368 include GNU Zile (an Emacs clone), and
2369 nvi (a clone of the original BSD @command{vi} editor).
2370 We strongly recommend storing that file on the target root file system, say,
2371 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2372 configuration file once you have rebooted into the newly-installed system.
2374 @xref{Using the Configuration System}, for an overview of the
2375 configuration file. The example configurations discussed in that
2376 section are available under @file{/etc/configuration} in the
2377 installation image. Thus, to get started with a system configuration
2378 providing a graphical display server (a ``desktop'' system), you can run
2379 something along these lines:
2383 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2384 # nano /mnt/etc/config.scm
2387 You should pay attention to what your configuration file contains, and
2392 Make sure the @code{bootloader-configuration} form refers to the target
2393 you want to install GRUB on. It should mention @code{grub-bootloader} if
2394 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2395 for newer UEFI systems. For legacy systems, the @code{target} field
2396 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2397 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2398 currently mounted and a @code{file-system} entry is specified in your
2402 Be sure that your file system labels match the value of their respective
2403 @code{device} fields in your @code{file-system} configuration, assuming
2404 your @code{file-system} configuration uses the @code{file-system-label}
2405 procedure in its @code{device} field.
2408 If there are encrypted or RAID partitions, make sure to add a
2409 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2412 Once you are done preparing the configuration file, the new system must
2413 be initialized (remember that the target root file system is mounted
2417 guix system init /mnt/etc/config.scm /mnt
2421 This copies all the necessary files and installs GRUB on
2422 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2423 more information, @pxref{Invoking guix system}. This command may trigger
2424 downloads or builds of missing packages, which can take some time.
2426 Once that command has completed---and hopefully succeeded!---you can run
2427 @command{reboot} and boot into the new system. The @code{root} password
2428 in the new system is initially empty; other users' passwords need to be
2429 initialized by running the @command{passwd} command as @code{root},
2430 unless your configuration specifies otherwise
2431 (@pxref{user-account-password, user account passwords}).
2432 @xref{After System Installation}, for what's next!
2435 @node After System Installation
2436 @section After System Installation
2438 Success, you've now booted into Guix System! From then on, you can update the
2439 system whenever you want by running, say:
2443 sudo guix system reconfigure /etc/config.scm
2447 This builds a new system generation with the latest packages and services
2448 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2449 your system includes the latest security updates (@pxref{Security Updates}).
2451 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2453 @cindex sudo vs. @command{guix pull}
2454 Note that @command{sudo guix} runs your user's @command{guix} command and
2455 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2456 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2458 The difference matters here, because @command{guix pull} updates
2459 the @command{guix} command and package definitions only for the user it is ran
2460 as. This means that if you choose to use @command{guix system reconfigure} in
2461 root's login shell, you'll need to @command{guix pull} separately.
2464 Join us on @code{#guix} on the Freenode IRC network or on
2465 @email{guix-devel@@gnu.org} to share your experience!
2468 @node Installing Guix in a VM
2469 @section Installing Guix in a Virtual Machine
2471 @cindex virtual machine, Guix System installation
2472 @cindex virtual private server (VPS)
2473 @cindex VPS (virtual private server)
2474 If you'd like to install Guix System in a virtual machine (VM) or on a
2475 virtual private server (VPS) rather than on your beloved machine, this
2478 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2479 disk image, follow these steps:
2483 First, retrieve and decompress the Guix system installation image as
2484 described previously (@pxref{USB Stick and DVD Installation}).
2487 Create a disk image that will hold the installed system. To make a
2488 qcow2-formatted disk image, use the @command{qemu-img} command:
2491 qemu-img create -f qcow2 guix-system.img 50G
2494 The resulting file will be much smaller than 50 GB (typically less than
2495 1 MB), but it will grow as the virtualized storage device is filled up.
2498 Boot the USB installation image in an VM:
2501 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2502 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2503 -drive file=guix-system.img \
2504 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2507 @code{-enable-kvm} is optional, but significantly improves performance,
2508 @pxref{Running Guix in a VM}.
2511 You're now root in the VM, proceed with the installation process.
2512 @xref{Preparing for Installation}, and follow the instructions.
2515 Once installation is complete, you can boot the system that's on your
2516 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2519 @node Building the Installation Image
2520 @section Building the Installation Image
2522 @cindex installation image
2523 The installation image described above was built using the @command{guix
2524 system} command, specifically:
2527 guix system disk-image --file-system-type=iso9660 \
2528 gnu/system/install.scm
2531 Have a look at @file{gnu/system/install.scm} in the source tree,
2532 and see also @ref{Invoking guix system} for more information
2533 about the installation image.
2535 @section Building the Installation Image for ARM Boards
2537 Many ARM boards require a specific variant of the
2538 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2540 If you build a disk image and the bootloader is not available otherwise
2541 (on another boot drive etc), it's advisable to build an image that
2542 includes the bootloader, specifically:
2545 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2548 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2549 board, a list of possible boards will be printed.
2551 @c *********************************************************************
2552 @node Package Management
2553 @chapter Package Management
2556 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2557 remove software packages, without having to know about their build
2558 procedures or dependencies. Guix also goes beyond this obvious set of
2561 This chapter describes the main features of Guix, as well as the
2562 package management tools it provides. Along with the command-line
2563 interface described below (@pxref{Invoking guix package, @code{guix
2564 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2565 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2566 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2570 guix install emacs-guix
2574 * Features:: How Guix will make your life brighter.
2575 * Invoking guix package:: Package installation, removal, etc.
2576 * Substitutes:: Downloading pre-built binaries.
2577 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2578 * Invoking guix gc:: Running the garbage collector.
2579 * Invoking guix pull:: Fetching the latest Guix and distribution.
2580 * Channels:: Customizing the package collection.
2581 * Invoking guix time-machine:: Running an older revision of Guix.
2582 * Inferiors:: Interacting with another revision of Guix.
2583 * Invoking guix describe:: Display information about your Guix revision.
2584 * Invoking guix archive:: Exporting and importing store files.
2590 When using Guix, each package ends up in the @dfn{package store}, in its
2591 own directory---something that resembles
2592 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2594 Instead of referring to these directories, users have their own
2595 @dfn{profile}, which points to the packages that they actually want to
2596 use. These profiles are stored within each user's home directory, at
2597 @code{$HOME/.guix-profile}.
2599 For example, @code{alice} installs GCC 4.7.2. As a result,
2600 @file{/home/alice/.guix-profile/bin/gcc} points to
2601 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2602 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2603 simply continues to point to
2604 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2605 coexist on the same system without any interference.
2607 The @command{guix package} command is the central tool to manage
2608 packages (@pxref{Invoking guix package}). It operates on the per-user
2609 profiles, and can be used @emph{with normal user privileges}.
2611 @cindex transactions
2612 The command provides the obvious install, remove, and upgrade
2613 operations. Each invocation is actually a @emph{transaction}: either
2614 the specified operation succeeds, or nothing happens. Thus, if the
2615 @command{guix package} process is terminated during the transaction,
2616 or if a power outage occurs during the transaction, then the user's
2617 profile remains in its previous state, and remains usable.
2619 In addition, any package transaction may be @emph{rolled back}. So, if,
2620 for example, an upgrade installs a new version of a package that turns
2621 out to have a serious bug, users may roll back to the previous instance
2622 of their profile, which was known to work well. Similarly, the global
2623 system configuration on Guix is subject to
2624 transactional upgrades and roll-back
2625 (@pxref{Using the Configuration System}).
2627 All packages in the package store may be @emph{garbage-collected}.
2628 Guix can determine which packages are still referenced by user
2629 profiles, and remove those that are provably no longer referenced
2630 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2631 generations of their profile so that the packages they refer to can be
2634 @cindex reproducibility
2635 @cindex reproducible builds
2636 Guix takes a @dfn{purely functional} approach to package
2637 management, as described in the introduction (@pxref{Introduction}).
2638 Each @file{/gnu/store} package directory name contains a hash of all the
2639 inputs that were used to build that package---compiler, libraries, build
2640 scripts, etc. This direct correspondence allows users to make sure a
2641 given package installation matches the current state of their
2642 distribution. It also helps maximize @dfn{build reproducibility}:
2643 thanks to the isolated build environments that are used, a given build
2644 is likely to yield bit-identical files when performed on different
2645 machines (@pxref{Invoking guix-daemon, container}).
2648 This foundation allows Guix to support @dfn{transparent binary/source
2649 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2650 available from an external source---a @dfn{substitute}, Guix just
2651 downloads it and unpacks it;
2652 otherwise, it builds the package from source, locally
2653 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2654 reproducible, users do not have to trust servers that provide
2655 substitutes: they can force a local build and @emph{challenge} providers
2656 (@pxref{Invoking guix challenge}).
2658 Control over the build environment is a feature that is also useful for
2659 developers. The @command{guix environment} command allows developers of
2660 a package to quickly set up the right development environment for their
2661 package, without having to manually install the dependencies of the
2662 package into their profile (@pxref{Invoking guix environment}).
2664 @cindex replication, of software environments
2665 @cindex provenance tracking, of software artifacts
2666 All of Guix and its package definitions is version-controlled, and
2667 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2668 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2669 Guix instance on a different machine or at a later point in time, which in
2670 turn allows you to @emph{replicate complete software environments}, while
2671 retaining precise @dfn{provenance tracking} of the software.
2673 @node Invoking guix package
2674 @section Invoking @command{guix package}
2676 @cindex installing packages
2677 @cindex removing packages
2678 @cindex package installation
2679 @cindex package removal
2680 The @command{guix package} command is the tool that allows users to
2681 install, upgrade, and remove packages, as well as rolling back to
2682 previous configurations. It operates only on the user's own profile,
2683 and works with normal user privileges (@pxref{Features}). Its syntax
2687 guix package @var{options}
2690 @cindex transactions
2691 Primarily, @var{options} specifies the operations to be performed during
2692 the transaction. Upon completion, a new profile is created, but
2693 previous @dfn{generations} of the profile remain available, should the user
2696 For example, to remove @code{lua} and install @code{guile} and
2697 @code{guile-cairo} in a single transaction:
2700 guix package -r lua -i guile guile-cairo
2703 @cindex aliases, for @command{guix package}
2704 For your convenience, we also provide the following aliases:
2708 @command{guix search} is an alias for @command{guix package -s},
2710 @command{guix install} is an alias for @command{guix package -i},
2712 @command{guix remove} is an alias for @command{guix package -r},
2714 @command{guix upgrade} is an alias for @command{guix package -u},
2716 and @command{guix show} is an alias for @command{guix package --show=}.
2719 These aliases are less expressive than @command{guix package} and provide
2720 fewer options, so in some cases you'll probably want to use @command{guix
2723 @command{guix package} also supports a @dfn{declarative approach}
2724 whereby the user specifies the exact set of packages to be available and
2725 passes it @i{via} the @option{--manifest} option
2726 (@pxref{profile-manifest, @option{--manifest}}).
2729 For each user, a symlink to the user's default profile is automatically
2730 created in @file{$HOME/.guix-profile}. This symlink always points to the
2731 current generation of the user's default profile. Thus, users can add
2732 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2733 variable, and so on.
2734 @cindex search paths
2735 If you are not using Guix System, consider adding the
2736 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2737 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2738 shells get all the right environment variable definitions:
2741 GUIX_PROFILE="$HOME/.guix-profile" ; \
2742 source "$HOME/.guix-profile/etc/profile"
2745 In a multi-user setup, user profiles are stored in a place registered as
2746 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2747 to (@pxref{Invoking guix gc}). That directory is normally
2748 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2749 @var{localstatedir} is the value passed to @code{configure} as
2750 @code{--localstatedir}, and @var{user} is the user name. The
2751 @file{per-user} directory is created when @command{guix-daemon} is
2752 started, and the @var{user} sub-directory is created by @command{guix
2755 The @var{options} can be among the following:
2759 @item --install=@var{package} @dots{}
2760 @itemx -i @var{package} @dots{}
2761 Install the specified @var{package}s.
2763 Each @var{package} may specify either a simple package name, such as
2764 @code{guile}, or a package name followed by an at-sign and version number,
2765 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2766 case, the newest version prefixed by @code{1.8} is selected.)
2768 If no version number is specified, the
2769 newest available version will be selected. In addition, @var{package}
2770 may contain a colon, followed by the name of one of the outputs of the
2771 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2772 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2773 name (and optionally version) are searched for among the GNU
2774 distribution modules (@pxref{Package Modules}).
2776 @cindex propagated inputs
2777 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2778 that automatically get installed along with the required package
2779 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2780 @code{package} objects}, for information about propagated inputs in
2781 package definitions).
2783 @anchor{package-cmd-propagated-inputs}
2784 An example is the GNU MPC library: its C header files refer to those of
2785 the GNU MPFR library, which in turn refer to those of the GMP library.
2786 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2787 in the profile; removing MPC also removes MPFR and GMP---unless they had
2788 also been explicitly installed by the user.
2790 Besides, packages sometimes rely on the definition of environment
2791 variables for their search paths (see explanation of
2792 @code{--search-paths} below). Any missing or possibly incorrect
2793 environment variable definitions are reported here.
2795 @item --install-from-expression=@var{exp}
2797 Install the package @var{exp} evaluates to.
2799 @var{exp} must be a Scheme expression that evaluates to a
2800 @code{<package>} object. This option is notably useful to disambiguate
2801 between same-named variants of a package, with expressions such as
2802 @code{(@@ (gnu packages base) guile-final)}.
2804 Note that this option installs the first output of the specified
2805 package, which may be insufficient when needing a specific output of a
2806 multiple-output package.
2808 @item --install-from-file=@var{file}
2809 @itemx -f @var{file}
2810 Install the package that the code within @var{file} evaluates to.
2812 As an example, @var{file} might contain a definition like this
2813 (@pxref{Defining Packages}):
2816 @include package-hello.scm
2819 Developers may find it useful to include such a @file{guix.scm} file
2820 in the root of their project source tree that can be used to test
2821 development snapshots and create reproducible development environments
2822 (@pxref{Invoking guix environment}).
2824 The @var{file} may also contain a JSON representation of one or more
2825 package definitions. Running @code{guix package -f} on
2826 @file{hello.json} with the following contents would result in installing
2827 the package @code{greeter} after building @code{myhello}:
2830 @verbatiminclude package-hello.json
2833 @item --remove=@var{package} @dots{}
2834 @itemx -r @var{package} @dots{}
2835 Remove the specified @var{package}s.
2837 As for @code{--install}, each @var{package} may specify a version number
2838 and/or output name in addition to the package name. For instance,
2839 @code{-r glibc:debug} would remove the @code{debug} output of
2842 @item --upgrade[=@var{regexp} @dots{}]
2843 @itemx -u [@var{regexp} @dots{}]
2844 @cindex upgrading packages
2845 Upgrade all the installed packages. If one or more @var{regexp}s are
2846 specified, upgrade only installed packages whose name matches a
2847 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2849 Note that this upgrades package to the latest version of packages found
2850 in the distribution currently installed. To update your distribution,
2851 you should regularly run @command{guix pull} (@pxref{Invoking guix
2854 @item --do-not-upgrade[=@var{regexp} @dots{}]
2855 When used together with the @code{--upgrade} option, do @emph{not}
2856 upgrade any packages whose name matches a @var{regexp}. For example, to
2857 upgrade all packages in the current profile except those containing the
2858 substring ``emacs'':
2861 $ guix package --upgrade . --do-not-upgrade emacs
2864 @item @anchor{profile-manifest}--manifest=@var{file}
2865 @itemx -m @var{file}
2866 @cindex profile declaration
2867 @cindex profile manifest
2868 Create a new generation of the profile from the manifest object
2869 returned by the Scheme code in @var{file}. This option can be repeated
2870 several times, in which case the manifests are concatenated.
2872 This allows you to @emph{declare} the profile's contents rather than
2873 constructing it through a sequence of @code{--install} and similar
2874 commands. The advantage is that @var{file} can be put under version
2875 control, copied to different machines to reproduce the same profile, and
2878 @c FIXME: Add reference to (guix profile) documentation when available.
2879 @var{file} must return a @dfn{manifest} object, which is roughly a list
2882 @findex packages->manifest
2884 (use-package-modules guile emacs)
2889 ;; Use a specific package output.
2890 (list guile-2.0 "debug")))
2893 @findex specifications->manifest
2894 In this example we have to know which modules define the @code{emacs}
2895 and @code{guile-2.0} variables to provide the right
2896 @code{use-package-modules} line, which can be cumbersome. We can
2897 instead provide regular package specifications and let
2898 @code{specifications->manifest} look up the corresponding package
2902 (specifications->manifest
2903 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2907 @cindex rolling back
2908 @cindex undoing transactions
2909 @cindex transactions, undoing
2910 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2911 the last transaction.
2913 When combined with options such as @code{--install}, roll back occurs
2914 before any other actions.
2916 When rolling back from the first generation that actually contains
2917 installed packages, the profile is made to point to the @dfn{zeroth
2918 generation}, which contains no files apart from its own metadata.
2920 After having rolled back, installing, removing, or upgrading packages
2921 overwrites previous future generations. Thus, the history of the
2922 generations in a profile is always linear.
2924 @item --switch-generation=@var{pattern}
2925 @itemx -S @var{pattern}
2927 Switch to a particular generation defined by @var{pattern}.
2929 @var{pattern} may be either a generation number or a number prefixed
2930 with ``+'' or ``-''. The latter means: move forward/backward by a
2931 specified number of generations. For example, if you want to return to
2932 the latest generation after @code{--roll-back}, use
2933 @code{--switch-generation=+1}.
2935 The difference between @code{--roll-back} and
2936 @code{--switch-generation=-1} is that @code{--switch-generation} will
2937 not make a zeroth generation, so if a specified generation does not
2938 exist, the current generation will not be changed.
2940 @item --search-paths[=@var{kind}]
2941 @cindex search paths
2942 Report environment variable definitions, in Bash syntax, that may be
2943 needed in order to use the set of installed packages. These environment
2944 variables are used to specify @dfn{search paths} for files used by some
2945 of the installed packages.
2947 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2948 environment variables to be defined so it can look for headers and
2949 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2950 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2951 library are installed in the profile, then @code{--search-paths} will
2952 suggest setting these variables to @code{@var{profile}/include} and
2953 @code{@var{profile}/lib}, respectively.
2955 The typical use case is to define these environment variables in the
2959 $ eval `guix package --search-paths`
2962 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2963 meaning that the returned environment variable definitions will either
2964 be exact settings, or prefixes or suffixes of the current value of these
2965 variables. When omitted, @var{kind} defaults to @code{exact}.
2967 This option can also be used to compute the @emph{combined} search paths
2968 of several profiles. Consider this example:
2971 $ guix package -p foo -i guile
2972 $ guix package -p bar -i guile-json
2973 $ guix package -p foo -p bar --search-paths
2976 The last command above reports about the @code{GUILE_LOAD_PATH}
2977 variable, even though, taken individually, neither @file{foo} nor
2978 @file{bar} would lead to that recommendation.
2981 @item --profile=@var{profile}
2982 @itemx -p @var{profile}
2983 Use @var{profile} instead of the user's default profile.
2985 @var{profile} must be the name of a file that will be created upon
2986 completion. Concretely, @var{profile} will be a mere symbolic link
2987 (``symlink'') pointing to the actual profile where packages are
2991 $ guix install hello -p ~/code/my-profile
2993 $ ~/code/my-profile/bin/hello
2997 All it takes to get rid of the profile is to remove this symlink and its
2998 siblings that point to specific generations:
3001 $ rm ~/code/my-profile ~/code/my-profile-*-link
3004 @item --list-profiles
3005 List all the user's profiles:
3008 $ guix package --list-profiles
3009 /home/charlie/.guix-profile
3010 /home/charlie/code/my-profile
3011 /home/charlie/code/devel-profile
3012 /home/charlie/tmp/test
3015 When running as root, list all the profiles of all the users.
3017 @cindex collisions, in a profile
3018 @cindex colliding packages in profiles
3019 @cindex profile collisions
3020 @item --allow-collisions
3021 Allow colliding packages in the new profile. Use at your own risk!
3023 By default, @command{guix package} reports as an error @dfn{collisions}
3024 in the profile. Collisions happen when two or more different versions
3025 or variants of a given package end up in the profile.
3028 Use the bootstrap Guile to build the profile. This option is only
3029 useful to distribution developers.
3033 In addition to these actions, @command{guix package} supports the
3034 following options to query the current state of a profile, or the
3035 availability of packages:
3039 @item --search=@var{regexp}
3040 @itemx -s @var{regexp}
3041 @cindex searching for packages
3042 List the available packages whose name, synopsis, or description matches
3043 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3044 Print all the metadata of matching packages in
3045 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3046 GNU recutils manual}).
3048 This allows specific fields to be extracted using the @command{recsel}
3049 command, for instance:
3052 $ guix package -s malloc | recsel -p name,version,relevance
3066 Similarly, to show the name of all the packages available under the
3067 terms of the GNU@tie{}LGPL version 3:
3070 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3077 It is also possible to refine search results using several @code{-s} flags to
3078 @command{guix package}, or several arguments to @command{guix search}. For
3079 example, the following command returns a list of board games (this time using
3080 the @command{guix search} alias):
3083 $ guix search '\<board\>' game | recsel -p name
3088 If we were to omit @code{-s game}, we would also get software packages
3089 that deal with printed circuit boards; removing the angle brackets
3090 around @code{board} would further add packages that have to do with
3093 And now for a more elaborate example. The following command searches
3094 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3095 libraries, and prints the name and synopsis of the matching packages:
3098 $ guix search crypto library | \
3099 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3103 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3104 information on @dfn{selection expressions} for @code{recsel -e}.
3106 @item --show=@var{package}
3107 Show details about @var{package}, taken from the list of available packages, in
3108 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3112 $ guix package --show=python | recsel -p name,version
3120 You may also specify the full name of a package to only get details about a
3121 specific version of it (this time using the @command{guix show} alias):
3123 $ guix show python@@3.4 | recsel -p name,version
3130 @item --list-installed[=@var{regexp}]
3131 @itemx -I [@var{regexp}]
3132 List the currently installed packages in the specified profile, with the
3133 most recently installed packages shown last. When @var{regexp} is
3134 specified, list only installed packages whose name matches @var{regexp}.
3136 For each installed package, print the following items, separated by
3137 tabs: the package name, its version string, the part of the package that
3138 is installed (for instance, @code{out} for the default output,
3139 @code{include} for its headers, etc.), and the path of this package in
3142 @item --list-available[=@var{regexp}]
3143 @itemx -A [@var{regexp}]
3144 List packages currently available in the distribution for this system
3145 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3146 available packages whose name matches @var{regexp}.
3148 For each package, print the following items separated by tabs: its name,
3149 its version string, the parts of the package (@pxref{Packages with
3150 Multiple Outputs}), and the source location of its definition.
3152 @item --list-generations[=@var{pattern}]
3153 @itemx -l [@var{pattern}]
3155 Return a list of generations along with their creation dates; for each
3156 generation, show the installed packages, with the most recently
3157 installed packages shown last. Note that the zeroth generation is never
3160 For each installed package, print the following items, separated by
3161 tabs: the name of a package, its version string, the part of the package
3162 that is installed (@pxref{Packages with Multiple Outputs}), and the
3163 location of this package in the store.
3165 When @var{pattern} is used, the command returns only matching
3166 generations. Valid patterns include:
3169 @item @emph{Integers and comma-separated integers}. Both patterns denote
3170 generation numbers. For instance, @code{--list-generations=1} returns
3173 And @code{--list-generations=1,8,2} outputs three generations in the
3174 specified order. Neither spaces nor trailing commas are allowed.
3176 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3177 specified generations and everything in between. Note that the start of
3178 a range must be smaller than its end.
3180 It is also possible to omit the endpoint. For example,
3181 @code{--list-generations=2..}, returns all generations starting from the
3184 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3185 or months by passing an integer along with the first letter of the
3186 duration. For example, @code{--list-generations=20d} lists generations
3187 that are up to 20 days old.
3190 @item --delete-generations[=@var{pattern}]
3191 @itemx -d [@var{pattern}]
3192 When @var{pattern} is omitted, delete all generations except the current
3195 This command accepts the same patterns as @option{--list-generations}.
3196 When @var{pattern} is specified, delete the matching generations. When
3197 @var{pattern} specifies a duration, generations @emph{older} than the
3198 specified duration match. For instance, @code{--delete-generations=1m}
3199 deletes generations that are more than one month old.
3201 If the current generation matches, it is @emph{not} deleted. Also, the
3202 zeroth generation is never deleted.
3204 Note that deleting generations prevents rolling back to them.
3205 Consequently, this command must be used with care.
3209 Finally, since @command{guix package} may actually start build
3210 processes, it supports all the common build options (@pxref{Common Build
3211 Options}). It also supports package transformation options, such as
3212 @option{--with-source} (@pxref{Package Transformation Options}).
3213 However, note that package transformations are lost when upgrading; to
3214 preserve transformations across upgrades, you should define your own
3215 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3216 (@pxref{Defining Packages}).
3219 @section Substitutes
3222 @cindex pre-built binaries
3223 Guix supports transparent source/binary deployment, which means that it
3224 can either build things locally, or download pre-built items from a
3225 server, or both. We call these pre-built items @dfn{substitutes}---they
3226 are substitutes for local build results. In many cases, downloading a
3227 substitute is much faster than building things locally.
3229 Substitutes can be anything resulting from a derivation build
3230 (@pxref{Derivations}). Of course, in the common case, they are
3231 pre-built package binaries, but source tarballs, for instance, which
3232 also result from derivation builds, can be available as substitutes.
3235 * Official Substitute Server:: One particular source of substitutes.
3236 * Substitute Server Authorization:: How to enable or disable substitutes.
3237 * Substitute Authentication:: How Guix verifies substitutes.
3238 * Proxy Settings:: How to get substitutes via proxy.
3239 * Substitution Failure:: What happens when substitution fails.
3240 * On Trusting Binaries:: How can you trust that binary blob?
3243 @node Official Substitute Server
3244 @subsection Official Substitute Server
3247 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3248 that builds packages from Guix continuously for some
3249 architectures, and makes them available as substitutes. This is the
3250 default source of substitutes; it can be overridden by passing the
3251 @option{--substitute-urls} option either to @command{guix-daemon}
3252 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3253 or to client tools such as @command{guix package}
3254 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3257 Substitute URLs can be either HTTP or HTTPS.
3258 HTTPS is recommended because communications are encrypted; conversely,
3259 using HTTP makes all communications visible to an eavesdropper, who
3260 could use the information gathered to determine, for instance, whether
3261 your system has unpatched security vulnerabilities.
3263 Substitutes from the official build farm are enabled by default when
3264 using Guix System (@pxref{GNU Distribution}). However,
3265 they are disabled by default when using Guix on a foreign distribution,
3266 unless you have explicitly enabled them via one of the recommended
3267 installation steps (@pxref{Installation}). The following paragraphs
3268 describe how to enable or disable substitutes for the official build
3269 farm; the same procedure can also be used to enable substitutes for any
3270 other substitute server.
3272 @node Substitute Server Authorization
3273 @subsection Substitute Server Authorization
3276 @cindex substitutes, authorization thereof
3277 @cindex access control list (ACL), for substitutes
3278 @cindex ACL (access control list), for substitutes
3279 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3281 must add its public key to the access control list (ACL) of archive
3282 imports, using the @command{guix archive} command (@pxref{Invoking guix
3283 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3284 be compromised and to serve genuine substitutes.
3286 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3287 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3288 the installation prefix of Guix. If you installed Guix from source,
3289 make sure you checked the GPG signature of
3290 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3291 Then, you can run something like this:
3294 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3297 Once this is in place, the output of a command like @code{guix build}
3298 should change from something like:
3301 $ guix build emacs --dry-run
3302 The following derivations would be built:
3303 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3304 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3305 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3306 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3314 $ guix build emacs --dry-run
3315 112.3 MB would be downloaded:
3316 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3317 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3318 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3319 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3324 The text changed from ``The following derivations would be built'' to
3325 ``112.3 MB would be downloaded''. This indicates that substitutes from
3326 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3327 possible, for future builds.
3329 @cindex substitutes, how to disable
3330 The substitute mechanism can be disabled globally by running
3331 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3332 guix-daemon}). It can also be disabled temporarily by passing the
3333 @code{--no-substitutes} option to @command{guix package}, @command{guix
3334 build}, and other command-line tools.
3336 @node Substitute Authentication
3337 @subsection Substitute Authentication
3339 @cindex digital signatures
3340 Guix detects and raises an error when attempting to use a substitute
3341 that has been tampered with. Likewise, it ignores substitutes that are
3342 not signed, or that are not signed by one of the keys listed in the ACL.
3344 There is one exception though: if an unauthorized server provides
3345 substitutes that are @emph{bit-for-bit identical} to those provided by
3346 an authorized server, then the unauthorized server becomes eligible for
3347 downloads. For example, assume we have chosen two substitute servers
3351 --substitute-urls="https://a.example.org https://b.example.org"
3355 @cindex reproducible builds
3356 If the ACL contains only the key for @code{b.example.org}, and if
3357 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3358 then Guix will download substitutes from @code{a.example.org} because it
3359 comes first in the list and can be considered a mirror of
3360 @code{b.example.org}. In practice, independent build machines usually
3361 produce the same binaries, thanks to bit-reproducible builds (see
3364 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3365 (in other words, the server is not authenticated), contrary to what
3366 HTTPS clients such as Web browsers usually do. This is because Guix
3367 authenticates substitute information itself, as explained above, which
3368 is what we care about (whereas X.509 certificates are about
3369 authenticating bindings between domain names and public keys.)
3371 @node Proxy Settings
3372 @subsection Proxy Settings
3375 Substitutes are downloaded over HTTP or HTTPS.
3376 The @code{http_proxy} environment
3377 variable can be set in the environment of @command{guix-daemon} and is
3378 honored for downloads of substitutes. Note that the value of
3379 @code{http_proxy} in the environment where @command{guix build},
3380 @command{guix package}, and other client commands are run has
3381 @emph{absolutely no effect}.
3383 @node Substitution Failure
3384 @subsection Substitution Failure
3386 Even when a substitute for a derivation is available, sometimes the
3387 substitution attempt will fail. This can happen for a variety of
3388 reasons: the substitute server might be offline, the substitute may
3389 recently have been deleted, the connection might have been interrupted,
3392 When substitutes are enabled and a substitute for a derivation is
3393 available, but the substitution attempt fails, Guix will attempt to
3394 build the derivation locally depending on whether or not
3395 @code{--fallback} was given (@pxref{fallback-option,, common build
3396 option @code{--fallback}}). Specifically, if @code{--fallback} was
3397 omitted, then no local build will be performed, and the derivation is
3398 considered to have failed. However, if @code{--fallback} was given,
3399 then Guix will attempt to build the derivation locally, and the success
3400 or failure of the derivation depends on the success or failure of the
3401 local build. Note that when substitutes are disabled or no substitute
3402 is available for the derivation in question, a local build will
3403 @emph{always} be performed, regardless of whether or not
3404 @code{--fallback} was given.
3406 To get an idea of how many substitutes are available right now, you can
3407 try running the @command{guix weather} command (@pxref{Invoking guix
3408 weather}). This command provides statistics on the substitutes provided
3411 @node On Trusting Binaries
3412 @subsection On Trusting Binaries
3414 @cindex trust, of pre-built binaries
3415 Today, each individual's control over their own computing is at the
3416 mercy of institutions, corporations, and groups with enough power and
3417 determination to subvert the computing infrastructure and exploit its
3418 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3419 convenient, we encourage users to also build on their own, or even run
3420 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3421 interesting target. One way to help is by publishing the software you
3422 build using @command{guix publish} so that others have one more choice
3423 of server to download substitutes from (@pxref{Invoking guix publish}).
3425 Guix has the foundations to maximize build reproducibility
3426 (@pxref{Features}). In most cases, independent builds of a given
3427 package or derivation should yield bit-identical results. Thus, through
3428 a diverse set of independent package builds, we can strengthen the
3429 integrity of our systems. The @command{guix challenge} command aims to
3430 help users assess substitute servers, and to assist developers in
3431 finding out about non-deterministic package builds (@pxref{Invoking guix
3432 challenge}). Similarly, the @option{--check} option of @command{guix
3433 build} allows users to check whether previously-installed substitutes
3434 are genuine by rebuilding them locally (@pxref{build-check,
3435 @command{guix build --check}}).
3437 In the future, we want Guix to have support to publish and retrieve
3438 binaries to/from other users, in a peer-to-peer fashion. If you would
3439 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3441 @node Packages with Multiple Outputs
3442 @section Packages with Multiple Outputs
3444 @cindex multiple-output packages
3445 @cindex package outputs
3448 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3449 source package leads to exactly one directory in the store. When running
3450 @command{guix install glibc}, one installs the default output of the
3451 GNU libc package; the default output is called @code{out}, but its name
3452 can be omitted as shown in this command. In this particular case, the
3453 default output of @code{glibc} contains all the C header files, shared
3454 libraries, static libraries, Info documentation, and other supporting
3457 Sometimes it is more appropriate to separate the various types of files
3458 produced from a single source package into separate outputs. For
3459 instance, the GLib C library (used by GTK+ and related packages)
3460 installs more than 20 MiB of reference documentation as HTML pages.
3461 To save space for users who do not need it, the documentation goes to a
3462 separate output, called @code{doc}. To install the main GLib output,
3463 which contains everything but the documentation, one would run:
3469 @cindex documentation
3470 The command to install its documentation is:
3473 guix install glib:doc
3476 Some packages install programs with different ``dependency footprints''.
3477 For instance, the WordNet package installs both command-line tools and
3478 graphical user interfaces (GUIs). The former depend solely on the C
3479 library, whereas the latter depend on Tcl/Tk and the underlying X
3480 libraries. In this case, we leave the command-line tools in the default
3481 output, whereas the GUIs are in a separate output. This allows users
3482 who do not need the GUIs to save space. The @command{guix size} command
3483 can help find out about such situations (@pxref{Invoking guix size}).
3484 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3486 There are several such multiple-output packages in the GNU distribution.
3487 Other conventional output names include @code{lib} for libraries and
3488 possibly header files, @code{bin} for stand-alone programs, and
3489 @code{debug} for debugging information (@pxref{Installing Debugging
3490 Files}). The outputs of a packages are listed in the third column of
3491 the output of @command{guix package --list-available} (@pxref{Invoking
3495 @node Invoking guix gc
3496 @section Invoking @command{guix gc}
3498 @cindex garbage collector
3500 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3501 The @command{guix gc} command allows users to explicitly run the garbage
3502 collector to reclaim space from the @file{/gnu/store} directory. It is
3503 the @emph{only} way to remove files from @file{/gnu/store}---removing
3504 files or directories manually may break it beyond repair!
3507 @cindex garbage collector roots
3508 The garbage collector has a set of known @dfn{roots}: any file under
3509 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3510 cannot be deleted; any other file is considered @dfn{dead} and may be
3511 deleted. The set of garbage collector roots (``GC roots'' for short)
3512 includes default user profiles; by default, the symlinks under
3513 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3514 added with @command{guix build --root}, for example (@pxref{Invoking
3515 guix build}). The @command{guix gc --list-roots} command lists them.
3517 Prior to running @code{guix gc --collect-garbage} to make space, it is
3518 often useful to remove old generations from user profiles; that way, old
3519 package builds referenced by those generations can be reclaimed. This
3520 is achieved by running @code{guix package --delete-generations}
3521 (@pxref{Invoking guix package}).
3523 Our recommendation is to run a garbage collection periodically, or when
3524 you are short on disk space. For instance, to guarantee that at least
3525 5@tie{}GB are available on your disk, simply run:
3531 It is perfectly safe to run as a non-interactive periodic job
3532 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3533 Running @command{guix gc} with no arguments will collect as
3534 much garbage as it can, but that is often inconvenient: you may find
3535 yourself having to rebuild or re-download software that is ``dead'' from
3536 the GC viewpoint but that is necessary to build other pieces of
3537 software---e.g., the compiler tool chain.
3539 The @command{guix gc} command has three modes of operation: it can be
3540 used to garbage-collect any dead files (the default), to delete specific
3541 files (the @code{--delete} option), to print garbage-collector
3542 information, or for more advanced queries. The garbage collection
3543 options are as follows:
3546 @item --collect-garbage[=@var{min}]
3547 @itemx -C [@var{min}]
3548 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3549 sub-directories. This is the default operation when no option is
3552 When @var{min} is given, stop once @var{min} bytes have been collected.
3553 @var{min} may be a number of bytes, or it may include a unit as a
3554 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3555 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3557 When @var{min} is omitted, collect all the garbage.
3559 @item --free-space=@var{free}
3560 @itemx -F @var{free}
3561 Collect garbage until @var{free} space is available under
3562 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3563 as @code{500MiB}, as described above.
3565 When @var{free} or more is already available in @file{/gnu/store}, do
3566 nothing and exit immediately.
3568 @item --delete-generations[=@var{duration}]
3569 @itemx -d [@var{duration}]
3570 Before starting the garbage collection process, delete all the generations
3571 older than @var{duration}, for all the user profiles; when run as root, this
3572 applies to all the profiles @emph{of all the users}.
3574 For example, this command deletes all the generations of all your profiles
3575 that are older than 2 months (except generations that are current), and then
3576 proceeds to free space until at least 10 GiB are available:
3579 guix gc -d 2m -F 10G
3584 Attempt to delete all the store files and directories specified as
3585 arguments. This fails if some of the files are not in the store, or if
3586 they are still live.
3588 @item --list-failures
3589 List store items corresponding to cached build failures.
3591 This prints nothing unless the daemon was started with
3592 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3593 @option{--cache-failures}}).
3596 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3600 List store items in use by currently running processes. These store
3601 items are effectively considered GC roots: they cannot be deleted.
3603 @item --clear-failures
3604 Remove the specified store items from the failed-build cache.
3606 Again, this option only makes sense when the daemon is started with
3607 @option{--cache-failures}. Otherwise, it does nothing.
3610 Show the list of dead files and directories still present in the
3611 store---i.e., files and directories no longer reachable from any root.
3614 Show the list of live store files and directories.
3618 In addition, the references among existing store files can be queried:
3624 @cindex package dependencies
3625 List the references (respectively, the referrers) of store files given
3631 List the requisites of the store files passed as arguments. Requisites
3632 include the store files themselves, their references, and the references
3633 of these, recursively. In other words, the returned list is the
3634 @dfn{transitive closure} of the store files.
3636 @xref{Invoking guix size}, for a tool to profile the size of the closure
3637 of an element. @xref{Invoking guix graph}, for a tool to visualize
3638 the graph of references.
3642 Return the derivation(s) leading to the given store items
3643 (@pxref{Derivations}).
3645 For example, this command:
3648 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3652 returns the @file{.drv} file(s) leading to the @code{emacs} package
3653 installed in your profile.
3655 Note that there may be zero matching @file{.drv} files, for instance
3656 because these files have been garbage-collected. There can also be more
3657 than one matching @file{.drv} due to fixed-output derivations.
3660 Lastly, the following options allow you to check the integrity of the
3661 store and to control disk usage.
3665 @item --verify[=@var{options}]
3666 @cindex integrity, of the store
3667 @cindex integrity checking
3668 Verify the integrity of the store.
3670 By default, make sure that all the store items marked as valid in the
3671 database of the daemon actually exist in @file{/gnu/store}.
3673 When provided, @var{options} must be a comma-separated list containing one
3674 or more of @code{contents} and @code{repair}.
3676 When passing @option{--verify=contents}, the daemon computes the
3677 content hash of each store item and compares it against its hash in the
3678 database. Hash mismatches are reported as data corruptions. Because it
3679 traverses @emph{all the files in the store}, this command can take a
3680 long time, especially on systems with a slow disk drive.
3682 @cindex repairing the store
3683 @cindex corruption, recovering from
3684 Using @option{--verify=repair} or @option{--verify=contents,repair}
3685 causes the daemon to try to repair corrupt store items by fetching
3686 substitutes for them (@pxref{Substitutes}). Because repairing is not
3687 atomic, and thus potentially dangerous, it is available only to the
3688 system administrator. A lightweight alternative, when you know exactly
3689 which items in the store are corrupt, is @command{guix build --repair}
3690 (@pxref{Invoking guix build}).
3693 @cindex deduplication
3694 Optimize the store by hard-linking identical files---this is
3695 @dfn{deduplication}.
3697 The daemon performs deduplication after each successful build or archive
3698 import, unless it was started with @code{--disable-deduplication}
3699 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3700 this option is primarily useful when the daemon was running with
3701 @code{--disable-deduplication}.
3705 @node Invoking guix pull
3706 @section Invoking @command{guix pull}
3708 @cindex upgrading Guix
3709 @cindex updating Guix
3710 @cindex @command{guix pull}
3712 Packages are installed or upgraded to the latest version available in
3713 the distribution currently available on your local machine. To update
3714 that distribution, along with the Guix tools, you must run @command{guix
3715 pull}: the command downloads the latest Guix source code and package
3716 descriptions, and deploys it. Source code is downloaded from a
3717 @uref{https://git-scm.com, Git} repository, by default the official
3718 GNU@tie{}Guix repository, though this can be customized.
3720 Specifically, @command{guix pull} downloads code from the @dfn{channels}
3721 (@pxref{Channels}) specified by one of the followings, in this order:
3725 the @option{--channels} option;
3727 the user's @file{~/.config/guix/channels.scm} file;
3729 the system-wide @file{/etc/guix/channels.scm} file;
3731 the built-in default channels specified in the @code{%default-channels}
3735 On completion, @command{guix package} will use packages and package
3736 versions from this just-retrieved copy of Guix. Not only that, but all
3737 the Guix commands and Scheme modules will also be taken from that latest
3738 version. New @command{guix} sub-commands added by the update also
3741 Any user can update their Guix copy using @command{guix pull}, and the
3742 effect is limited to the user who ran @command{guix pull}. For
3743 instance, when user @code{root} runs @command{guix pull}, this has no
3744 effect on the version of Guix that user @code{alice} sees, and vice
3747 The result of running @command{guix pull} is a @dfn{profile} available
3748 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3749 make sure to add it to the beginning of your search path so that you use
3750 the latest version, and similarly for the Info manual
3751 (@pxref{Documentation}):
3754 export PATH="$HOME/.config/guix/current/bin:$PATH"
3755 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3758 The @code{--list-generations} or @code{-l} option lists past generations
3759 produced by @command{guix pull}, along with details about their provenance:
3763 Generation 1 Jun 10 2018 00:18:18
3765 repository URL: https://git.savannah.gnu.org/git/guix.git
3766 branch: origin/master
3767 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3769 Generation 2 Jun 11 2018 11:02:49
3771 repository URL: https://git.savannah.gnu.org/git/guix.git
3772 branch: origin/master
3773 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3774 2 new packages: keepalived, libnfnetlink
3775 6 packages upgraded: emacs-nix-mode@@2.0.4,
3776 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3777 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3779 Generation 3 Jun 13 2018 23:31:07 (current)
3781 repository URL: https://git.savannah.gnu.org/git/guix.git
3782 branch: origin/master
3783 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3784 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3785 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3788 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3789 describe the current status of Guix.
3791 This @code{~/.config/guix/current} profile works exactly like the profiles
3792 created by @command{guix package} (@pxref{Invoking guix package}). That
3793 is, you can list generations, roll back to the previous
3794 generation---i.e., the previous Guix---and so on:
3797 $ guix pull --roll-back
3798 switched from generation 3 to 2
3799 $ guix pull --delete-generations=1
3800 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3803 You can also use @command{guix package} (@pxref{Invoking guix package})
3804 to manage the profile by naming it explicitly:
3806 $ guix package -p ~/.config/guix/current --roll-back
3807 switched from generation 3 to 2
3808 $ guix package -p ~/.config/guix/current --delete-generations=1
3809 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3812 The @command{guix pull} command is usually invoked with no arguments,
3813 but it supports the following options:
3816 @item --url=@var{url}
3817 @itemx --commit=@var{commit}
3818 @itemx --branch=@var{branch}
3819 Download code for the @code{guix} channel from the specified @var{url}, at the
3820 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3821 string), or @var{branch}.
3823 @cindex @file{channels.scm}, configuration file
3824 @cindex configuration file for channels
3825 These options are provided for convenience, but you can also specify your
3826 configuration in the @file{~/.config/guix/channels.scm} file or using the
3827 @option{--channels} option (see below).
3829 @item --channels=@var{file}
3830 @itemx -C @var{file}
3831 Read the list of channels from @var{file} instead of
3832 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
3833 @var{file} must contain Scheme code that
3834 evaluates to a list of channel objects. @xref{Channels}, for more
3837 @cindex channel news
3840 Display the list of packages added or upgraded since the previous
3841 generation, as well as, occasionally, news written by channel authors
3842 for their users (@pxref{Channels, Writing Channel News}).
3844 The package information is the same as displayed upon @command{guix
3845 pull} completion, but without ellipses; it is also similar to the output
3846 of @command{guix pull -l} for the last generation (see below).
3848 @item --list-generations[=@var{pattern}]
3849 @itemx -l [@var{pattern}]
3850 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3851 is provided, the subset of generations that match @var{pattern}.
3852 The syntax of @var{pattern} is the same as with @code{guix package
3853 --list-generations} (@pxref{Invoking guix package}).
3856 @cindex rolling back
3857 @cindex undoing transactions
3858 @cindex transactions, undoing
3859 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
3860 undo the last transaction.
3862 @item --switch-generation=@var{pattern}
3863 @itemx -S @var{pattern}
3865 Switch to a particular generation defined by @var{pattern}.
3867 @var{pattern} may be either a generation number or a number prefixed
3868 with ``+'' or ``-''. The latter means: move forward/backward by a
3869 specified number of generations. For example, if you want to return to
3870 the latest generation after @code{--roll-back}, use
3871 @code{--switch-generation=+1}.
3873 @item --delete-generations[=@var{pattern}]
3874 @itemx -d [@var{pattern}]
3875 When @var{pattern} is omitted, delete all generations except the current
3878 This command accepts the same patterns as @option{--list-generations}.
3879 When @var{pattern} is specified, delete the matching generations. When
3880 @var{pattern} specifies a duration, generations @emph{older} than the
3881 specified duration match. For instance, @code{--delete-generations=1m}
3882 deletes generations that are more than one month old.
3884 If the current generation matches, it is @emph{not} deleted.
3886 Note that deleting generations prevents rolling back to them.
3887 Consequently, this command must be used with care.
3889 @xref{Invoking guix describe}, for a way to display information about the
3890 current generation only.
3892 @item --profile=@var{profile}
3893 @itemx -p @var{profile}
3894 Use @var{profile} instead of @file{~/.config/guix/current}.
3898 Show which channel commit(s) would be used and what would be built or
3899 substituted but do not actually do it.
3901 @item --system=@var{system}
3902 @itemx -s @var{system}
3903 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3904 the system type of the build host.
3907 Produce verbose output, writing build logs to the standard error output.
3910 Use the bootstrap Guile to build the latest Guix. This option is only
3911 useful to Guix developers.
3914 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3915 repository and branch to pull from, as well as @emph{additional} repositories
3916 containing package modules that should be deployed. @xref{Channels}, for more
3919 In addition, @command{guix pull} supports all the common build options
3920 (@pxref{Common Build Options}).
3926 @cindex @file{channels.scm}, configuration file
3927 @cindex configuration file for channels
3928 @cindex @command{guix pull}, configuration file
3929 @cindex configuration of @command{guix pull}
3930 Guix and its package collection are updated by running @command{guix pull}
3931 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3932 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3933 customized by defining @dfn{channels} in the
3934 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3935 of a Git repository to be deployed, and @command{guix pull} can be instructed
3936 to pull from one or more channels. In other words, channels can be used to
3937 @emph{customize} and to @emph{extend} Guix, as we will see below.
3939 @subsection Using a Custom Guix Channel
3941 The channel called @code{guix} specifies where Guix itself---its command-line
3942 tools as well as its package collection---should be downloaded. For instance,
3943 suppose you want to update from your own copy of the Guix repository at
3944 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3945 write in @code{~/.config/guix/channels.scm} this specification:
3948 ;; Tell 'guix pull' to use my own repo.
3951 (url "https://example.org/my-guix.git")
3952 (branch "super-hacks")))
3956 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3957 branch of the repository at @code{example.org}.
3959 @subsection Specifying Additional Channels
3961 @cindex extending the package collection (channels)
3962 @cindex personal packages (channels)
3963 @cindex channels, for personal packages
3964 You can also specify @emph{additional channels} to pull from. Let's say you
3965 have a bunch of custom package variants or personal packages that you think
3966 would make little sense to contribute to the Guix project, but would like to
3967 have these packages transparently available to you at the command line. You
3968 would first write modules containing those package definitions (@pxref{Package
3969 Modules}), maintain them in a Git repository, and then you and anyone else can
3970 use it as an additional channel to get packages from. Neat, no?
3972 @c What follows stems from discussions at
3973 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3974 @c earlier discussions on guix-devel@gnu.org.
3976 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3977 publish your personal channel to the world, we would like to share a few words
3982 Before publishing a channel, please consider contributing your package
3983 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3984 to free software of all sorts, and packages in Guix proper are readily
3985 available to all Guix users and benefit from the project's quality assurance
3989 When you maintain package definitions outside Guix, we, Guix developers,
3990 consider that @emph{the compatibility burden is on you}. Remember that
3991 package modules and package definitions are just Scheme code that uses various
3992 programming interfaces (APIs). We want to remain free to change these APIs to
3993 keep improving Guix, possibly in ways that break your channel. We never
3994 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
3998 Corollary: if you're using an external channel and that channel breaks, please
3999 @emph{report the issue to the channel authors}, not to the Guix project.
4002 You've been warned! Having said this, we believe external channels are a
4003 practical way to exert your freedom to augment Guix' package collection and to
4004 share your improvements, which are basic tenets of
4005 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
4006 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
4009 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
4010 @command{guix pull} to pull from it @emph{in addition} to the default Guix
4013 @vindex %default-channels
4015 ;; Add my personal packages to those Guix provides.
4017 (name 'my-personal-packages)
4018 (url "https://example.org/personal-packages.git"))
4023 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4024 add a channel the list of channels that the variable @code{%default-channels}
4025 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4026 Manual}). With this file in place, @command{guix pull} builds not only Guix
4027 but also the package modules from your own repository. The result in
4028 @file{~/.config/guix/current} is the union of Guix with your own package
4032 $ guix pull --list-generations
4034 Generation 19 Aug 27 2018 16:20:48
4036 repository URL: https://git.savannah.gnu.org/git/guix.git
4038 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4039 my-personal-packages dd3df5e
4040 repository URL: https://example.org/personal-packages.git
4042 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4043 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
4044 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4048 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4049 both Guix and packages from the @code{my-personal-packages} channel. Among
4050 the new and upgraded packages that are listed, some like @code{my-gimp} and
4051 @code{my-emacs-with-cool-features} might come from
4052 @code{my-personal-packages}, while others come from the Guix default channel.
4054 To create a channel, create a Git repository containing your own package
4055 modules and make it available. The repository can contain anything, but a
4056 useful channel will contain Guile modules that export packages. Once you
4057 start using a channel, Guix will behave as if the root directory of that
4058 channel's Git repository has been added to the Guile load path (@pxref{Load
4059 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
4060 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
4061 module, then the module will be available under the name @code{(my-packages
4062 my-tools)}, and you will be able to use it like any other module
4063 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
4065 @cindex dependencies, channels
4066 @cindex meta-data, channels
4067 @subsection Declaring Channel Dependencies
4069 Channel authors may decide to augment a package collection provided by other
4070 channels. They can declare their channel to be dependent on other channels in
4071 a meta-data file @file{.guix-channel}, which is to be placed in the root of
4072 the channel repository.
4074 The meta-data file should contain a simple S-expression like this:
4081 (name some-collection)
4082 (url "https://example.org/first-collection.git"))
4084 (name some-other-collection)
4085 (url "https://example.org/second-collection.git")
4086 (branch "testing"))))
4089 In the above example this channel is declared to depend on two other channels,
4090 which will both be fetched automatically. The modules provided by the channel
4091 will be compiled in an environment where the modules of all these declared
4092 channels are available.
4094 For the sake of reliability and maintainability, you should avoid dependencies
4095 on channels that you don't control, and you should aim to keep the number of
4096 dependencies to a minimum.
4098 @cindex subdirectory, channels
4099 @subsection Package Modules in a Sub-directory
4101 As a channel author, you may want to keep your channel modules in a
4102 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4103 add a meta-data file @file{.guix-channel} that contains:
4111 @cindex news, for channels
4112 @subsection Writing Channel News
4114 Channel authors may occasionally want to communicate to their users
4115 information about important changes in the channel. You'd send them all
4116 an email, but that's not convenient.
4118 Instead, channels can provide a @dfn{news file}; when the channel users
4119 run @command{guix pull}, that news file is automatically read and
4120 @command{guix pull --news} can display the announcements that correspond
4121 to the new commits that have been pulled, if any.
4123 To do that, channel authors must first declare the name of the news file
4124 in their @file{.guix-channel} file:
4129 (news-file "etc/news.txt"))
4132 The news file itself, @file{etc/news.txt} in this example, must look
4133 something like this:
4138 (entry (tag "the-bug-fix")
4139 (title (en "Fixed terrible bug")
4141 (body (en "@@emph@{Good news@}! It's fixed!")
4142 (eo "Certe ĝi pli bone funkcias nun!")))
4143 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4144 (title (en "Added a great package")
4145 (ca "Què vol dir guix?"))
4146 (body (en "Don't miss the @@code@{hello@} package!"))))
4149 The file consists of a list of @dfn{news entries}. Each entry is
4150 associated with a commit or tag: it describes changes made in this
4151 commit, possibly in preceding commits as well. Users see entries only
4152 the first time they obtain the commit the entry refers to.
4154 The @code{title} field should be a one-line summary while @code{body}
4155 can be arbitrarily long, and both can contain Texinfo markup
4156 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4157 a list of language tag/message tuples, which allows @command{guix pull}
4158 to display news in the language that corresponds to the user's locale.
4160 If you want to translate news using a gettext-based workflow, you can
4161 extract translatable strings with @command{xgettext} (@pxref{xgettext
4162 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4163 you write news entries in English first, the command below creates a PO
4164 file containing the strings to translate:
4167 xgettext -o news.po -l scheme -ken etc/news.scm
4170 To sum up, yes, you could use your channel as a blog. But beware, this
4171 is @emph{not quite} what your users might expect.
4173 @subsection Replicating Guix
4175 @cindex pinning, channels
4176 @cindex replicating Guix
4177 @cindex reproducibility, of Guix
4178 The @command{guix pull --list-generations} output above shows precisely which
4179 commits were used to build this instance of Guix. We can thus replicate it,
4180 say, on another machine, by providing a channel specification in
4181 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4184 ;; Deploy specific commits of my channels of interest.
4187 (url "https://git.savannah.gnu.org/git/guix.git")
4188 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
4190 (name 'my-personal-packages)
4191 (url "https://example.org/personal-packages.git")
4192 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4195 The @command{guix describe --format=channels} command can even generate this
4196 list of channels directly (@pxref{Invoking guix describe}). The resulting
4197 file can be used with the -C options of @command{guix pull}
4198 (@pxref{Invoking guix pull}) or @command{guix time-machine}
4199 (@pxref{Invoking guix time-machine}).
4201 At this point the two machines run the @emph{exact same Guix}, with access to
4202 the @emph{exact same packages}. The output of @command{guix build gimp} on
4203 one machine will be exactly the same, bit for bit, as the output of the same
4204 command on the other machine. It also means both machines have access to all
4205 the source code of Guix and, transitively, to all the source code of every
4208 This gives you super powers, allowing you to track the provenance of binary
4209 artifacts with very fine grain, and to reproduce software environments at
4210 will---some sort of ``meta reproducibility'' capabilities, if you will.
4211 @xref{Inferiors}, for another way to take advantage of these super powers.
4213 @node Invoking guix time-machine
4214 @section Invoking @command{guix time-machine}
4216 @cindex @command{guix time-machine}
4217 @cindex pinning, channels
4218 @cindex replicating Guix
4219 @cindex reproducibility, of Guix
4221 The @command{guix time-machine} command provides access to other
4222 revisions of Guix, for example to install older versions of packages,
4223 or to reproduce a computation in an identical environment. The revision
4224 of Guix to be used is defined by a commit or by a channel
4225 description file created by @command{guix describe}
4226 (@pxref{Invoking guix describe}).
4228 The general syntax is:
4231 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4234 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4235 @command{guix} command of the specified revision. The @var{options} that define
4236 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4239 @item --url=@var{url}
4240 @itemx --commit=@var{commit}
4241 @itemx --branch=@var{branch}
4242 Use the @code{guix} channel from the specified @var{url}, at the
4243 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4244 string), or @var{branch}.
4246 @item --channels=@var{file}
4247 @itemx -C @var{file}
4248 Read the list of channels from @var{file}. @var{file} must contain
4249 Scheme code that evaluates to a list of channel objects.
4250 @xref{Channels} for more information.
4253 As for @command{guix pull}, the absence of any options means that the
4254 the latest commit on the master branch will be used. The command
4257 guix time-machine -- build hello
4260 will thus build the package @code{hello} as defined in the master branch,
4261 which is in general a newer revision of Guix than you have installed.
4262 Time travel works in both directions!
4264 Note that @command{guix time-machine} can trigger builds of channels and
4265 their dependencies, and these are controlled by the standard build
4266 options (@pxref{Common Build Options}).
4271 @c TODO: Remove this once we're more confident about API stability.
4273 The functionality described here is a ``technology preview'' as of version
4274 @value{VERSION}. As such, the interface is subject to change.
4278 @cindex composition of Guix revisions
4279 Sometimes you might need to mix packages from the revision of Guix you're
4280 currently running with packages available in a different revision of Guix.
4281 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4282 revisions in arbitrary ways.
4284 @cindex inferior packages
4285 Technically, an ``inferior'' is essentially a separate Guix process connected
4286 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4287 @code{(guix inferior)} module allows you to create inferiors and to
4288 communicate with them. It also provides a high-level interface to browse and
4289 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4291 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4292 to interact with a separate revision of Guix. For example, let's assume you
4293 want to install in your profile the current @code{guile} package, along with
4294 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4295 because the newer @code{guile-json} has an incompatible API and you want to
4296 run your code against the old API@. To do that, you could write a manifest for
4297 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4298 manifest, you would create an inferior for that old Guix revision you care
4299 about, and you would look up the @code{guile-json} package in the inferior:
4302 (use-modules (guix inferior) (guix channels)
4303 (srfi srfi-1)) ;for 'first'
4306 ;; This is the old revision from which we want to
4307 ;; extract guile-json.
4310 (url "https://git.savannah.gnu.org/git/guix.git")
4312 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4315 ;; An inferior representing the above revision.
4316 (inferior-for-channels channels))
4318 ;; Now create a manifest with the current "guile" package
4319 ;; and the old "guile-json" package.
4321 (list (first (lookup-inferior-packages inferior "guile-json"))
4322 (specification->package "guile")))
4325 On its first run, @command{guix package --manifest} might have to build the
4326 channel you specified before it can create the inferior; subsequent runs will
4327 be much faster because the Guix revision will be cached.
4329 The @code{(guix inferior)} module provides the following procedures to open an
4332 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4333 [#:cache-directory] [#:ttl]
4334 Return an inferior for @var{channels}, a list of channels. Use the cache at
4335 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4336 This procedure opens a new connection to the build daemon.
4338 As a side effect, this procedure may build or substitute binaries for
4339 @var{channels}, which can take time.
4342 @deffn {Scheme Procedure} open-inferior @var{directory} @
4343 [#:command "bin/guix"]
4344 Open the inferior Guix in @var{directory}, running
4345 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4346 the inferior could not be launched.
4349 @cindex inferior packages
4350 The procedures listed below allow you to obtain and manipulate inferior
4353 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4354 Return the list of packages known to @var{inferior}.
4357 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4359 Return the sorted list of inferior packages matching @var{name} in
4360 @var{inferior}, with highest version numbers first. If @var{version} is true,
4361 return only packages with a version number prefixed by @var{version}.
4364 @deffn {Scheme Procedure} inferior-package? @var{obj}
4365 Return true if @var{obj} is an inferior package.
4368 @deffn {Scheme Procedure} inferior-package-name @var{package}
4369 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4370 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4371 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4372 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4373 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4374 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4375 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4376 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4377 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4378 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4379 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4380 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4381 These procedures are the counterpart of package record accessors
4382 (@pxref{package Reference}). Most of them work by querying the inferior
4383 @var{package} comes from, so the inferior must still be live when you call
4387 Inferior packages can be used transparently like any other package or
4388 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4389 transparently handled by the @code{packages->manifest} procedure, which is
4390 commonly use in manifests (@pxref{Invoking guix package, the
4391 @option{--manifest} option of @command{guix package}}). Thus you can insert
4392 an inferior package pretty much anywhere you would insert a regular package:
4393 in manifests, in the @code{packages} field of your @code{operating-system}
4394 declaration, and so on.
4396 @node Invoking guix describe
4397 @section Invoking @command{guix describe}
4399 @cindex reproducibility
4400 @cindex replicating Guix
4401 Often you may want to answer questions like: ``Which revision of Guix am I
4402 using?'' or ``Which channels am I using?'' This is useful information in many
4403 situations: if you want to @emph{replicate} an environment on a different
4404 machine or user account, if you want to report a bug or to determine what
4405 change in the channels you are using caused it, or if you want to record your
4406 system state for reproducibility purposes. The @command{guix describe}
4407 command answers these questions.
4409 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4410 displays the channel(s) that it was built from, including their repository URL
4411 and commit IDs (@pxref{Channels}):
4415 Generation 10 Sep 03 2018 17:32:44 (current)
4417 repository URL: https://git.savannah.gnu.org/git/guix.git
4419 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4422 If you're familiar with the Git version control system, this is similar in
4423 spirit to @command{git describe}; the output is also similar to that of
4424 @command{guix pull --list-generations}, but limited to the current generation
4425 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4426 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4427 information is all it takes to describe the revision of Guix you're using, and
4428 also to replicate it.
4430 To make it easier to replicate Guix, @command{guix describe} can also be asked
4431 to return a list of channels instead of the human-readable description above:
4434 $ guix describe -f channels
4437 (url "https://git.savannah.gnu.org/git/guix.git")
4439 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4443 You can save this to a file and feed it to @command{guix pull -C} on some
4444 other machine or at a later point in time, which will instantiate @emph{this
4445 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4446 From there on, since you're able to deploy the same revision of Guix, you can
4447 just as well @emph{replicate a complete software environment}. We humbly
4448 think that this is @emph{awesome}, and we hope you'll like it too!
4450 The details of the options supported by @command{guix describe} are as
4454 @item --format=@var{format}
4455 @itemx -f @var{format}
4456 Produce output in the specified @var{format}, one of:
4460 produce human-readable output;
4462 produce a list of channel specifications that can be passed to @command{guix
4463 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4467 produce a list of channel specifications in JSON format;
4469 produce a list of channel specifications in Recutils format.
4472 @item --profile=@var{profile}
4473 @itemx -p @var{profile}
4474 Display information about @var{profile}.
4477 @node Invoking guix archive
4478 @section Invoking @command{guix archive}
4480 @cindex @command{guix archive}
4482 The @command{guix archive} command allows users to @dfn{export} files
4483 from the store into a single archive, and to later @dfn{import} them on
4484 a machine that runs Guix.
4485 In particular, it allows store files to be transferred from one machine
4486 to the store on another machine.
4489 If you're looking for a way to produce archives in a format suitable for
4490 tools other than Guix, @pxref{Invoking guix pack}.
4493 @cindex exporting store items
4494 To export store files as an archive to standard output, run:
4497 guix archive --export @var{options} @var{specifications}...
4500 @var{specifications} may be either store file names or package
4501 specifications, as for @command{guix package} (@pxref{Invoking guix
4502 package}). For instance, the following command creates an archive
4503 containing the @code{gui} output of the @code{git} package and the main
4504 output of @code{emacs}:
4507 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4510 If the specified packages are not built yet, @command{guix archive}
4511 automatically builds them. The build process may be controlled with the
4512 common build options (@pxref{Common Build Options}).
4514 To transfer the @code{emacs} package to a machine connected over SSH,
4518 guix archive --export -r emacs | ssh the-machine guix archive --import
4522 Similarly, a complete user profile may be transferred from one machine
4523 to another like this:
4526 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4527 ssh the-machine guix archive --import
4531 However, note that, in both examples, all of @code{emacs} and the
4532 profile as well as all of their dependencies are transferred (due to
4533 @code{-r}), regardless of what is already available in the store on the
4534 target machine. The @code{--missing} option can help figure out which
4535 items are missing from the target store. The @command{guix copy}
4536 command simplifies and optimizes this whole process, so this is probably
4537 what you should use in this case (@pxref{Invoking guix copy}).
4539 @cindex nar, archive format
4540 @cindex normalized archive (nar)
4541 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4542 comparable in spirit to `tar', but with differences
4543 that make it more appropriate for our purposes. First, rather than
4544 recording all Unix metadata for each file, the nar format only mentions
4545 the file type (regular, directory, or symbolic link); Unix permissions
4546 and owner/group are dismissed. Second, the order in which directory
4547 entries are stored always follows the order of file names according to
4548 the C locale collation order. This makes archive production fully
4551 When exporting, the daemon digitally signs the contents of the archive,
4552 and that digital signature is appended. When importing, the daemon
4553 verifies the signature and rejects the import in case of an invalid
4554 signature or if the signing key is not authorized.
4555 @c FIXME: Add xref to daemon doc about signatures.
4557 The main options are:
4561 Export the specified store files or packages (see below.) Write the
4562 resulting archive to the standard output.
4564 Dependencies are @emph{not} included in the output, unless
4565 @code{--recursive} is passed.
4569 When combined with @code{--export}, this instructs @command{guix
4570 archive} to include dependencies of the given items in the archive.
4571 Thus, the resulting archive is self-contained: it contains the closure
4572 of the exported store items.
4575 Read an archive from the standard input, and import the files listed
4576 therein into the store. Abort if the archive has an invalid digital
4577 signature, or if it is signed by a public key not among the authorized
4578 keys (see @code{--authorize} below.)
4581 Read a list of store file names from the standard input, one per line,
4582 and write on the standard output the subset of these files missing from
4585 @item --generate-key[=@var{parameters}]
4586 @cindex signing, archives
4587 Generate a new key pair for the daemon. This is a prerequisite before
4588 archives can be exported with @code{--export}. Note that this operation
4589 usually takes time, because it needs to gather enough entropy to
4590 generate the key pair.
4592 The generated key pair is typically stored under @file{/etc/guix}, in
4593 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4594 key, which must be kept secret.) When @var{parameters} is omitted,
4595 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4596 versions before 1.6.0, it is a 4096-bit RSA key.
4597 Alternatively, @var{parameters} can specify
4598 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4599 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4600 Libgcrypt Reference Manual}).
4603 @cindex authorizing, archives
4604 Authorize imports signed by the public key passed on standard input.
4605 The public key must be in ``s-expression advanced format''---i.e., the
4606 same format as the @file{signing-key.pub} file.
4608 The list of authorized keys is kept in the human-editable file
4609 @file{/etc/guix/acl}. The file contains
4610 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4611 s-expressions''} and is structured as an access-control list in the
4612 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4615 @item --extract=@var{directory}
4616 @itemx -x @var{directory}
4617 Read a single-item archive as served by substitute servers
4618 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4619 low-level operation needed in only very narrow use cases; see below.
4621 For example, the following command extracts the substitute for Emacs
4622 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4626 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4627 | gunzip | guix archive -x /tmp/emacs
4630 Single-item archives are different from multiple-item archives produced
4631 by @command{guix archive --export}; they contain a single store item,
4632 and they do @emph{not} embed a signature. Thus this operation does
4633 @emph{no} signature verification and its output should be considered
4636 The primary purpose of this operation is to facilitate inspection of
4637 archive contents coming from possibly untrusted substitute servers
4638 (@pxref{Invoking guix challenge}).
4642 Read a single-item archive as served by substitute servers
4643 (@pxref{Substitutes}) and print the list of files it contains, as in
4648 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4649 | lzip -d | guix archive -t
4655 @c *********************************************************************
4657 @chapter Development
4659 @cindex software development
4660 If you are a software developer, Guix provides tools that you should find
4661 helpful---independently of the language you're developing in. This is what
4662 this chapter is about.
4664 The @command{guix environment} command provides a convenient way to set up
4665 @dfn{development environments} containing all the dependencies and tools
4666 necessary to work on the software package of your choice. The @command{guix
4667 pack} command allows you to create @dfn{application bundles} that can be
4668 easily distributed to users who do not run Guix.
4671 * Invoking guix environment:: Setting up development environments.
4672 * Invoking guix pack:: Creating software bundles.
4673 * Packages for C Development:: Working with C code with Guix.
4676 @node Invoking guix environment
4677 @section Invoking @command{guix environment}
4679 @cindex reproducible build environments
4680 @cindex development environments
4681 @cindex @command{guix environment}
4682 @cindex environment, package build environment
4683 The purpose of @command{guix environment} is to assist hackers in
4684 creating reproducible development environments without polluting their
4685 package profile. The @command{guix environment} tool takes one or more
4686 packages, builds all of their inputs, and creates a shell
4687 environment to use them.
4689 The general syntax is:
4692 guix environment @var{options} @var{package}@dots{}
4695 The following example spawns a new shell set up for the development of
4699 guix environment guile
4702 If the needed dependencies are not built yet, @command{guix environment}
4703 automatically builds them. The environment of the new shell is an augmented
4704 version of the environment that @command{guix environment} was run in.
4705 It contains the necessary search paths for building the given package
4706 added to the existing environment variables. To create a ``pure''
4707 environment, in which the original environment variables have been unset,
4708 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4709 environment variables such as @code{PATH} in their @file{~/.bashrc}
4710 file. As a consequence, when @code{guix environment} launches it, Bash
4711 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4712 environment variables. It is an error to define such environment
4713 variables in @file{.bashrc}; instead, they should be defined in
4714 @file{.bash_profile}, which is sourced only by log-in shells.
4715 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4716 details on Bash start-up files.}.
4718 @vindex GUIX_ENVIRONMENT
4719 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4720 variable in the shell it spawns; its value is the file name of the
4721 profile of this environment. This allows users to, say, define a
4722 specific prompt for development environments in their @file{.bashrc}
4723 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4726 if [ -n "$GUIX_ENVIRONMENT" ]
4728 export PS1="\u@@\h \w [dev]\$ "
4733 ...@: or to browse the profile:
4736 $ ls "$GUIX_ENVIRONMENT/bin"
4739 Additionally, more than one package may be specified, in which case the
4740 union of the inputs for the given packages are used. For example, the
4741 command below spawns a shell where all of the dependencies of both Guile
4742 and Emacs are available:
4745 guix environment guile emacs
4748 Sometimes an interactive shell session is not desired. An arbitrary
4749 command may be invoked by placing the @code{--} token to separate the
4750 command from the rest of the arguments:
4753 guix environment guile -- make -j4
4756 In other situations, it is more convenient to specify the list of
4757 packages needed in the environment. For example, the following command
4758 runs @command{python} from an environment containing Python@tie{}2.7 and
4762 guix environment --ad-hoc python2-numpy python-2.7 -- python
4765 Furthermore, one might want the dependencies of a package and also some
4766 additional packages that are not build-time or runtime dependencies, but
4767 are useful when developing nonetheless. Because of this, the
4768 @code{--ad-hoc} flag is positional. Packages appearing before
4769 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4770 added to the environment. Packages appearing after are interpreted as
4771 packages that will be added to the environment directly. For example,
4772 the following command creates a Guix development environment that
4773 additionally includes Git and strace:
4776 guix environment --pure guix --ad-hoc git strace
4779 Sometimes it is desirable to isolate the environment as much as
4780 possible, for maximal purity and reproducibility. In particular, when
4781 using Guix on a host distro that is not Guix System, it is desirable to
4782 prevent access to @file{/usr/bin} and other system-wide resources from
4783 the development environment. For example, the following command spawns
4784 a Guile REPL in a ``container'' where only the store and the current
4785 working directory are mounted:
4788 guix environment --ad-hoc --container guile -- guile
4792 The @code{--container} option requires Linux-libre 3.19 or newer.
4795 The available options are summarized below.
4798 @item --root=@var{file}
4799 @itemx -r @var{file}
4800 @cindex persistent environment
4801 @cindex garbage collector root, for environments
4802 Make @var{file} a symlink to the profile for this environment, and
4803 register it as a garbage collector root.
4805 This is useful if you want to protect your environment from garbage
4806 collection, to make it ``persistent''.
4808 When this option is omitted, the environment is protected from garbage
4809 collection only for the duration of the @command{guix environment}
4810 session. This means that next time you recreate the same environment,
4811 you could have to rebuild or re-download packages. @xref{Invoking guix
4812 gc}, for more on GC roots.
4814 @item --expression=@var{expr}
4815 @itemx -e @var{expr}
4816 Create an environment for the package or list of packages that
4817 @var{expr} evaluates to.
4819 For example, running:
4822 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4825 starts a shell with the environment for this specific variant of the
4831 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4834 starts a shell with all the base system packages available.
4836 The above commands only use the default output of the given packages.
4837 To select other outputs, two element tuples can be specified:
4840 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4843 @item --load=@var{file}
4844 @itemx -l @var{file}
4845 Create an environment for the package or list of packages that the code
4846 within @var{file} evaluates to.
4848 As an example, @var{file} might contain a definition like this
4849 (@pxref{Defining Packages}):
4852 @verbatiminclude environment-gdb.scm
4855 @item --manifest=@var{file}
4856 @itemx -m @var{file}
4857 Create an environment for the packages contained in the manifest object
4858 returned by the Scheme code in @var{file}. This option can be repeated
4859 several times, in which case the manifests are concatenated.
4861 This is similar to the same-named option in @command{guix package}
4862 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4866 Include all specified packages in the resulting environment, as if an
4867 @i{ad hoc} package were defined with them as inputs. This option is
4868 useful for quickly creating an environment without having to write a
4869 package expression to contain the desired inputs.
4871 For instance, the command:
4874 guix environment --ad-hoc guile guile-sdl -- guile
4877 runs @command{guile} in an environment where Guile and Guile-SDL are
4880 Note that this example implicitly asks for the default output of
4881 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4882 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4883 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4885 This option may be composed with the default behavior of @command{guix
4886 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4887 as packages whose dependencies will be added to the environment, the
4888 default behavior. Packages appearing after are interpreted as packages
4889 that will be added to the environment directly.
4892 Unset existing environment variables when building the new environment, except
4893 those specified with @option{--preserve} (see below.) This has the effect of
4894 creating an environment in which search paths only contain package inputs.
4896 @item --preserve=@var{regexp}
4897 @itemx -E @var{regexp}
4898 When used alongside @option{--pure}, preserve the environment variables
4899 matching @var{regexp}---in other words, put them on a ``white list'' of
4900 environment variables that must be preserved. This option can be repeated
4904 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4908 This example runs @command{mpirun} in a context where the only environment
4909 variables defined are @code{PATH}, environment variables whose name starts
4910 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4913 @item --search-paths
4914 Display the environment variable definitions that make up the
4917 @item --system=@var{system}
4918 @itemx -s @var{system}
4919 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4924 Run @var{command} within an isolated container. The current working
4925 directory outside the container is mapped inside the container.
4926 Additionally, unless overridden with @code{--user}, a dummy home
4927 directory is created that matches the current user's home directory, and
4928 @file{/etc/passwd} is configured accordingly.
4930 The spawned process runs as the current user outside the container. Inside
4931 the container, it has the same UID and GID as the current user, unless
4932 @option{--user} is passed (see below.)
4936 For containers, share the network namespace with the host system.
4937 Containers created without this flag only have access to the loopback
4940 @item --link-profile
4942 For containers, link the environment profile to
4943 @file{~/.guix-profile} within the container. This is equivalent to
4944 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4945 within the container. Linking will fail and abort the environment if
4946 the directory already exists, which will certainly be the case if
4947 @command{guix environment} was invoked in the user's home directory.
4949 Certain packages are configured to look in
4950 @code{~/.guix-profile} for configuration files and data;@footnote{For
4951 example, the @code{fontconfig} package inspects
4952 @file{~/.guix-profile/share/fonts} for additional fonts.}
4953 @code{--link-profile} allows these programs to behave as expected within
4956 @item --user=@var{user}
4957 @itemx -u @var{user}
4958 For containers, use the username @var{user} in place of the current
4959 user. The generated @file{/etc/passwd} entry within the container will
4960 contain the name @var{user}, the home directory will be
4961 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4962 the UID and GID inside the container are 1000. @var{user}
4963 need not exist on the system.
4965 Additionally, any shared or exposed path (see @code{--share} and
4966 @code{--expose} respectively) whose target is within the current user's
4967 home directory will be remapped relative to @file{/home/USER}; this
4968 includes the automatic mapping of the current working directory.
4971 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4973 guix environment --container --user=foo \
4974 --expose=$HOME/test \
4975 --expose=/tmp/target=$HOME/target
4978 While this will limit the leaking of user identity through home paths
4979 and each of the user fields, this is only one useful component of a
4980 broader privacy/anonymity solution---not one in and of itself.
4983 For containers, the default behavior is to share the current working
4984 directory with the isolated container and immediately change to that
4985 directory within the container. If this is undesirable, @code{--no-cwd}
4986 will cause the current working directory to @emph{not} be automatically
4987 shared and will change to the user's home directory within the container
4988 instead. See also @code{--user}.
4990 @item --expose=@var{source}[=@var{target}]
4991 @itemx --share=@var{source}[=@var{target}]
4992 For containers, @code{--expose} (resp. @code{--share}) exposes the file
4993 system @var{source} from the host system as the read-only
4994 (resp. writable) file system @var{target} within the container. If
4995 @var{target} is not specified, @var{source} is used as the target mount
4996 point in the container.
4998 The example below spawns a Guile REPL in a container in which the user's
4999 home directory is accessible read-only via the @file{/exchange}
5003 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5008 @command{guix environment}
5009 also supports all of the common build options that @command{guix
5010 build} supports (@pxref{Common Build Options}) as well as package
5011 transformation options (@pxref{Package Transformation Options}).
5013 @node Invoking guix pack
5014 @section Invoking @command{guix pack}
5016 Occasionally you want to pass software to people who are not (yet!)
5017 lucky enough to be using Guix. You'd tell them to run @command{guix
5018 package -i @var{something}}, but that's not possible in this case. This
5019 is where @command{guix pack} comes in.
5022 If you are looking for ways to exchange binaries among machines that
5023 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5024 publish}, and @ref{Invoking guix archive}.
5029 @cindex application bundle
5030 @cindex software bundle
5031 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5032 @dfn{software bundle}: it creates a tarball or some other archive
5033 containing the binaries of the software you're interested in, and all
5034 its dependencies. The resulting archive can be used on any machine that
5035 does not have Guix, and people can run the exact same binaries as those
5036 you have with Guix. The pack itself is created in a bit-reproducible
5037 fashion, so anyone can verify that it really contains the build results
5038 that you pretend to be shipping.
5040 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5041 their dependencies, you can run:
5044 $ guix pack guile emacs geiser
5046 /gnu/store/@dots{}-pack.tar.gz
5049 The result here is a tarball containing a @file{/gnu/store} directory
5050 with all the relevant packages. The resulting tarball contains a
5051 @dfn{profile} with the three packages of interest; the profile is the
5052 same as would be created by @command{guix package -i}. It is this
5053 mechanism that is used to create Guix's own standalone binary tarball
5054 (@pxref{Binary Installation}).
5056 Users of this pack would have to run
5057 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5058 find inconvenient. To work around it, you can create, say, a
5059 @file{/opt/gnu/bin} symlink to the profile:
5062 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5066 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5068 @cindex relocatable binaries, with @command{guix pack}
5069 What if the recipient of your pack does not have root privileges on
5070 their machine, and thus cannot unpack it in the root file system? In
5071 that case, you will want to use the @code{--relocatable} option (see
5072 below). This option produces @dfn{relocatable binaries}, meaning they
5073 they can be placed anywhere in the file system hierarchy: in the example
5074 above, users can unpack your tarball in their home directory and
5075 directly run @file{./opt/gnu/bin/guile}.
5077 @cindex Docker, build an image with guix pack
5078 Alternatively, you can produce a pack in the Docker image format using
5079 the following command:
5082 guix pack -f docker -S /bin=bin guile guile-readline
5086 The result is a tarball that can be passed to the @command{docker load}
5087 command, followed by @code{docker run}:
5090 docker load < @var{file}
5091 docker run -ti guile-guile-readline /bin/guile
5095 where @var{file} is the image returned by @var{guix pack}, and
5096 @code{guile-guile-readline} is its ``image tag''. See the
5097 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5098 documentation} for more information.
5100 @cindex Singularity, build an image with guix pack
5101 @cindex SquashFS, build an image with guix pack
5102 Yet another option is to produce a SquashFS image with the following
5106 guix pack -f squashfs bash guile emacs geiser
5110 The result is a SquashFS file system image that can either be mounted or
5111 directly be used as a file system container image with the
5112 @uref{https://www.sylabs.io/docs/, Singularity container execution
5113 environment}, using commands like @command{singularity shell} or
5114 @command{singularity exec}.
5116 Several command-line options allow you to customize your pack:
5119 @item --format=@var{format}
5120 @itemx -f @var{format}
5121 Produce a pack in the given @var{format}.
5123 The available formats are:
5127 This is the default format. It produces a tarball containing all the
5128 specified binaries and symlinks.
5131 This produces a tarball that follows the
5132 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5133 Docker Image Specification}. The ``repository name'' as it appears in
5134 the output of the @command{docker images} command is computed from
5135 package names passed on the command line or in the manifest file.
5138 This produces a SquashFS image containing all the specified binaries and
5139 symlinks, as well as empty mount points for virtual file systems like
5143 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5144 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5145 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5146 with something like:
5149 guix pack -f squashfs bash @dots{}
5152 If you forget the @code{bash} (or similar) package, @command{singularity
5153 run} and @command{singularity exec} will fail with an unhelpful ``no
5154 such file or directory'' message.
5158 @cindex relocatable binaries
5161 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5162 anywhere in the file system hierarchy and run from there.
5164 When this option is passed once, the resulting binaries require support for
5165 @dfn{user namespaces} in the kernel Linux; when passed
5166 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5167 PRoot support, can be thought of as the abbreviation of ``Really
5168 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
5169 if user namespaces are unavailable, and essentially work anywhere---see below
5170 for the implications.
5172 For example, if you create a pack containing Bash with:
5175 guix pack -RR -S /mybin=bin bash
5179 ...@: you can copy that pack to a machine that lacks Guix, and from your
5180 home directory as a normal user, run:
5188 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5189 @file{/gnu/store} shows up and contains all the dependencies of
5190 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5191 altogether! That is probably the simplest way to deploy Guix-built
5192 software on a non-Guix machine.
5195 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5196 the kernel Linux, which allows unprivileged users to mount or change root.
5197 Old versions of Linux did not support it, and some GNU/Linux distributions
5200 To produce relocatable binaries that work even in the absence of user
5201 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5202 case, binaries will try user namespace support and fall back to PRoot if user
5203 namespaces are not supported.
5205 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
5206 support for file system virtualization. It achieves that by using the
5207 @code{ptrace} system call on the running program. This approach has the
5208 advantage to work without requiring special kernel support, but it incurs
5209 run-time overhead every time a system call is made.
5212 @cindex entry point, for Docker images
5213 @item --entry-point=@var{command}
5214 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5215 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5216 support it. @var{command} must be relative to the profile contained in the
5219 The entry point specifies the command that tools like @code{docker run} or
5220 @code{singularity run} automatically start by default. For example, you can
5224 guix pack -f docker --entry-point=bin/guile guile
5227 The resulting pack can easily be loaded and @code{docker run} with no extra
5228 arguments will spawn @code{bin/guile}:
5231 docker load -i pack.tar.gz
5232 docker run @var{image-id}
5235 @item --expression=@var{expr}
5236 @itemx -e @var{expr}
5237 Consider the package @var{expr} evaluates to.
5239 This has the same purpose as the same-named option in @command{guix
5240 build} (@pxref{Additional Build Options, @code{--expression} in
5241 @command{guix build}}).
5243 @item --manifest=@var{file}
5244 @itemx -m @var{file}
5245 Use the packages contained in the manifest object returned by the Scheme
5246 code in @var{file}. This option can be repeated several times, in which
5247 case the manifests are concatenated.
5249 This has a similar purpose as the same-named option in @command{guix
5250 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5251 same manifest files. It allows you to define a collection of packages
5252 once and use it both for creating profiles and for creating archives
5253 for use on machines that do not have Guix installed. Note that you can
5254 specify @emph{either} a manifest file @emph{or} a list of packages,
5257 @item --system=@var{system}
5258 @itemx -s @var{system}
5259 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5260 the system type of the build host.
5262 @item --target=@var{triplet}
5263 @cindex cross-compilation
5264 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5265 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
5266 configuration triplets,, autoconf, Autoconf}).
5268 @item --compression=@var{tool}
5269 @itemx -C @var{tool}
5270 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5271 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
5273 @item --symlink=@var{spec}
5274 @itemx -S @var{spec}
5275 Add the symlinks specified by @var{spec} to the pack. This option can
5276 appear several times.
5278 @var{spec} has the form @code{@var{source}=@var{target}}, where
5279 @var{source} is the symlink that will be created and @var{target} is the
5282 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5283 symlink pointing to the @file{bin} sub-directory of the profile.
5285 @item --save-provenance
5286 Save provenance information for the packages passed on the command line.
5287 Provenance information includes the URL and commit of the channels in use
5290 Provenance information is saved in the
5291 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5292 usual package metadata---the name and version of each package, their
5293 propagated inputs, and so on. It is useful information to the recipient of
5294 the pack, who then knows how the pack was (supposedly) obtained.
5296 This option is not enabled by default because, like timestamps, provenance
5297 information contributes nothing to the build process. In other words, there
5298 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5299 Recording such ``silent'' metadata in the output thus potentially breaks the
5300 source-to-binary bitwise reproducibility property.
5302 @item --root=@var{file}
5303 @itemx -r @var{file}
5304 @cindex garbage collector root, for packs
5305 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5308 @item --localstatedir
5309 @itemx --profile-name=@var{name}
5310 Include the ``local state directory'', @file{/var/guix}, in the resulting
5311 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5312 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5313 @file{~root/.guix-profile}.
5315 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5316 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5317 the pack means that the store is ``complete'' and manageable by Guix;
5318 not providing it pack means that the store is ``dead'': items cannot be
5319 added to it or removed from it after extraction of the pack.
5321 One use case for this is the Guix self-contained binary tarball
5322 (@pxref{Binary Installation}).
5326 Print the name of the derivation that builds the pack.
5329 Use the bootstrap binaries to build the pack. This option is only
5330 useful to Guix developers.
5333 In addition, @command{guix pack} supports all the common build options
5334 (@pxref{Common Build Options}) and all the package transformation
5335 options (@pxref{Package Transformation Options}).
5337 @node Packages for C Development
5338 @section Packages for C Development
5342 @cindex linker wrapper
5343 @cindex toolchain, for C development
5345 If you need a complete toolchain for compiling and linking C or C++
5346 source code, use the @code{gcc-toolchain} package. This package
5347 provides a complete GCC toolchain for C/C++ development, including GCC
5348 itself, the GNU C Library (headers and binaries, plus debugging symbols
5349 in the @code{debug} output), Binutils, and a linker wrapper.
5351 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
5352 passed to the linker, add corresponding @code{-rpath} arguments, and
5353 invoke the actual linker with this new set of arguments. You can instruct the
5354 wrapper to refuse to link against libraries not in the store by setting the
5355 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
5359 @c *********************************************************************
5360 @node Programming Interface
5361 @chapter Programming Interface
5363 GNU Guix provides several Scheme programming interfaces (APIs) to
5364 define, build, and query packages. The first interface allows users to
5365 write high-level package definitions. These definitions refer to
5366 familiar packaging concepts, such as the name and version of a package,
5367 its build system, and its dependencies. These definitions can then be
5368 turned into concrete build actions.
5370 Build actions are performed by the Guix daemon, on behalf of users. In a
5371 standard setup, the daemon has write access to the store---the
5372 @file{/gnu/store} directory---whereas users do not. The recommended
5373 setup also has the daemon perform builds in chroots, under a specific
5374 build users, to minimize interference with the rest of the system.
5377 Lower-level APIs are available to interact with the daemon and the
5378 store. To instruct the daemon to perform a build action, users actually
5379 provide it with a @dfn{derivation}. A derivation is a low-level
5380 representation of the build actions to be taken, and the environment in
5381 which they should occur---derivations are to package definitions what
5382 assembly is to C programs. The term ``derivation'' comes from the fact
5383 that build results @emph{derive} from them.
5385 This chapter describes all these APIs in turn, starting from high-level
5386 package definitions.
5389 * Package Modules:: Packages from the programmer's viewpoint.
5390 * Defining Packages:: Defining new packages.
5391 * Build Systems:: Specifying how packages are built.
5392 * The Store:: Manipulating the package store.
5393 * Derivations:: Low-level interface to package derivations.
5394 * The Store Monad:: Purely functional interface to the store.
5395 * G-Expressions:: Manipulating build expressions.
5396 * Invoking guix repl:: Fiddling with Guix interactively.
5399 @node Package Modules
5400 @section Package Modules
5402 From a programming viewpoint, the package definitions of the
5403 GNU distribution are provided by Guile modules in the @code{(gnu packages
5404 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5405 packages @dots{})} module name space are not necessarily ``GNU
5406 packages''. This module naming scheme follows the usual Guile module
5407 naming convention: @code{gnu} means that these modules are distributed
5408 as part of the GNU system, and @code{packages} identifies modules that
5409 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5410 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5411 module exports a variable named @code{emacs}, which is bound to a
5412 @code{<package>} object (@pxref{Defining Packages}).
5414 The @code{(gnu packages @dots{})} module name space is
5415 automatically scanned for packages by the command-line tools. For
5416 instance, when running @code{guix install emacs}, all the @code{(gnu
5417 packages @dots{})} modules are scanned until one that exports a package
5418 object whose name is @code{emacs} is found. This package search
5419 facility is implemented in the @code{(gnu packages)} module.
5421 @cindex customization, of packages
5422 @cindex package module search path
5423 Users can store package definitions in modules with different
5424 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5425 name and module name must match. For instance, the @code{(my-packages
5426 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5427 relative to the load path specified with @option{--load-path} or
5428 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5429 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5430 these package definitions visible to the user interfaces:
5434 By adding the directory containing your package modules to the search path
5435 with the @code{-L} flag of @command{guix package} and other commands
5436 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5437 environment variable described below.
5440 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5441 pulls from it. A channel is essentially a Git repository containing package
5442 modules. @xref{Channels}, for more information on how to define and use
5446 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5448 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5449 This is a colon-separated list of directories to search for additional
5450 package modules. Directories listed in this variable take precedence
5451 over the own modules of the distribution.
5454 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5455 each package is built based solely on other packages in the
5456 distribution. The root of this dependency graph is a small set of
5457 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5458 bootstrap)} module. For more information on bootstrapping,
5459 @pxref{Bootstrapping}.
5461 @node Defining Packages
5462 @section Defining Packages
5464 The high-level interface to package definitions is implemented in the
5465 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5466 example, the package definition, or @dfn{recipe}, for the GNU Hello
5467 package looks like this:
5470 (define-module (gnu packages hello)
5471 #:use-module (guix packages)
5472 #:use-module (guix download)
5473 #:use-module (guix build-system gnu)
5474 #:use-module (guix licenses)
5475 #:use-module (gnu packages gawk))
5477 (define-public hello
5483 (uri (string-append "mirror://gnu/hello/hello-" version
5487 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5488 (build-system gnu-build-system)
5489 (arguments '(#:configure-flags '("--enable-silent-rules")))
5490 (inputs `(("gawk" ,gawk)))
5491 (synopsis "Hello, GNU world: An example GNU package")
5492 (description "Guess what GNU Hello prints!")
5493 (home-page "https://www.gnu.org/software/hello/")
5498 Without being a Scheme expert, the reader may have guessed the meaning
5499 of the various fields here. This expression binds the variable
5500 @code{hello} to a @code{<package>} object, which is essentially a record
5501 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5502 This package object can be inspected using procedures found in the
5503 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5504 returns---surprise!---@code{"hello"}.
5506 With luck, you may be able to import part or all of the definition of
5507 the package you are interested in from another repository, using the
5508 @code{guix import} command (@pxref{Invoking guix import}).
5510 In the example above, @var{hello} is defined in a module of its own,
5511 @code{(gnu packages hello)}. Technically, this is not strictly
5512 necessary, but it is convenient to do so: all the packages defined in
5513 modules under @code{(gnu packages @dots{})} are automatically known to
5514 the command-line tools (@pxref{Package Modules}).
5516 There are a few points worth noting in the above package definition:
5520 The @code{source} field of the package is an @code{<origin>} object
5521 (@pxref{origin Reference}, for the complete reference).
5522 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5523 meaning that the source is a file to be downloaded over FTP or HTTP.
5525 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5526 the GNU mirrors defined in @code{(guix download)}.
5528 The @code{sha256} field specifies the expected SHA256 hash of the file
5529 being downloaded. It is mandatory, and allows Guix to check the
5530 integrity of the file. The @code{(base32 @dots{})} form introduces the
5531 base32 representation of the hash. You can obtain this information with
5532 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5533 hash} (@pxref{Invoking guix hash}).
5536 When needed, the @code{origin} form can also have a @code{patches} field
5537 listing patches to be applied, and a @code{snippet} field giving a
5538 Scheme expression to modify the source code.
5541 @cindex GNU Build System
5542 The @code{build-system} field specifies the procedure to build the
5543 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5544 represents the familiar GNU Build System, where packages may be
5545 configured, built, and installed with the usual @code{./configure &&
5546 make && make check && make install} command sequence.
5549 The @code{arguments} field specifies options for the build system
5550 (@pxref{Build Systems}). Here it is interpreted by
5551 @var{gnu-build-system} as a request run @file{configure} with the
5552 @code{--enable-silent-rules} flag.
5558 What about these quote (@code{'}) characters? They are Scheme syntax to
5559 introduce a literal list; @code{'} is synonymous with @code{quote}.
5560 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5561 for details. Here the value of the @code{arguments} field is a list of
5562 arguments passed to the build system down the road, as with @code{apply}
5563 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5566 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5567 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5568 @code{#:configure-flags} is a keyword used to pass a keyword argument
5569 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5573 The @code{inputs} field specifies inputs to the build process---i.e.,
5574 build-time or run-time dependencies of the package. Here, we define an
5575 input called @code{"gawk"} whose value is that of the @var{gawk}
5576 variable; @var{gawk} is itself bound to a @code{<package>} object.
5578 @cindex backquote (quasiquote)
5581 @cindex comma (unquote)
5585 @findex unquote-splicing
5586 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5587 us to introduce a literal list in the @code{inputs} field, while
5588 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5589 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5592 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5593 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5594 of ensuring that they are present (@pxref{Build Systems}).
5596 However, any other dependencies need to be specified in the
5597 @code{inputs} field. Any dependency not specified here will simply be
5598 unavailable to the build process, possibly leading to a build failure.
5601 @xref{package Reference}, for a full description of possible fields.
5603 Once a package definition is in place, the
5604 package may actually be built using the @code{guix build} command-line
5605 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5606 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5607 package definition using the @command{guix edit} command
5608 (@pxref{Invoking guix edit}).
5609 @xref{Packaging Guidelines}, for
5610 more information on how to test package definitions, and
5611 @ref{Invoking guix lint}, for information on how to check a definition
5612 for style conformance.
5613 @vindex GUIX_PACKAGE_PATH
5614 Lastly, @pxref{Channels}, for information
5615 on how to extend the distribution by adding your own package definitions
5618 Finally, updating the package definition to a new upstream version
5619 can be partly automated by the @command{guix refresh} command
5620 (@pxref{Invoking guix refresh}).
5622 Behind the scenes, a derivation corresponding to the @code{<package>}
5623 object is first computed by the @code{package-derivation} procedure.
5624 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5625 The build actions it prescribes may then be realized by using the
5626 @code{build-derivations} procedure (@pxref{The Store}).
5628 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5629 Return the @code{<derivation>} object of @var{package} for @var{system}
5630 (@pxref{Derivations}).
5632 @var{package} must be a valid @code{<package>} object, and @var{system}
5633 must be a string denoting the target system type---e.g.,
5634 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5635 must be a connection to the daemon, which operates on the store
5636 (@pxref{The Store}).
5640 @cindex cross-compilation
5641 Similarly, it is possible to compute a derivation that cross-builds a
5642 package for some other system:
5644 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5645 @var{package} @var{target} [@var{system}]
5646 Return the @code{<derivation>} object of @var{package} cross-built from
5647 @var{system} to @var{target}.
5649 @var{target} must be a valid GNU triplet denoting the target hardware
5650 and operating system, such as @code{"mips64el-linux-gnu"}
5651 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5654 @cindex package transformations
5655 @cindex input rewriting
5656 @cindex dependency tree rewriting
5657 Packages can be manipulated in arbitrary ways. An example of a useful
5658 transformation is @dfn{input rewriting}, whereby the dependency tree of
5659 a package is rewritten by replacing specific inputs by others:
5661 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5662 [@var{rewrite-name}]
5663 Return a procedure that, when passed a package, replaces its direct and
5664 indirect dependencies (but not its implicit inputs) according to
5665 @var{replacements}. @var{replacements} is a list of package pairs; the
5666 first element of each pair is the package to replace, and the second one
5669 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5670 the name of a package and returns its new name after rewrite.
5674 Consider this example:
5677 (define libressl-instead-of-openssl
5678 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5680 (package-input-rewriting `((,openssl . ,libressl))))
5682 (define git-with-libressl
5683 (libressl-instead-of-openssl git))
5687 Here we first define a rewriting procedure that replaces @var{openssl}
5688 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5689 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5690 This is exactly what the @option{--with-input} command-line option does
5691 (@pxref{Package Transformation Options, @option{--with-input}}).
5693 The following variant of @code{package-input-rewriting} can match packages to
5694 be replaced by name rather than by identity.
5696 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5697 Return a procedure that, given a package, applies the given @var{replacements} to
5698 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5699 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5700 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5701 replacement for that package.
5704 The example above could be rewritten this way:
5707 (define libressl-instead-of-openssl
5708 ;; Replace all the packages called "openssl" with LibreSSL.
5709 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5712 The key difference here is that, this time, packages are matched by spec and
5713 not by identity. In other words, any package in the graph that is called
5714 @code{openssl} will be replaced.
5716 A more generic procedure to rewrite a package dependency graph is
5717 @code{package-mapping}: it supports arbitrary changes to nodes in the
5720 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5721 Return a procedure that, given a package, applies @var{proc} to all the packages
5722 depended on and returns the resulting package. The procedure stops recursion
5723 when @var{cut?} returns true for a given package.
5727 * package Reference:: The package data type.
5728 * origin Reference:: The origin data type.
5732 @node package Reference
5733 @subsection @code{package} Reference
5735 This section summarizes all the options available in @code{package}
5736 declarations (@pxref{Defining Packages}).
5738 @deftp {Data Type} package
5739 This is the data type representing a package recipe.
5743 The name of the package, as a string.
5745 @item @code{version}
5746 The version of the package, as a string.
5749 An object telling how the source code for the package should be
5750 acquired. Most of the time, this is an @code{origin} object, which
5751 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5752 can also be any other ``file-like'' object such as a @code{local-file},
5753 which denotes a file from the local file system (@pxref{G-Expressions,
5754 @code{local-file}}).
5756 @item @code{build-system}
5757 The build system that should be used to build the package (@pxref{Build
5760 @item @code{arguments} (default: @code{'()})
5761 The arguments that should be passed to the build system. This is a
5762 list, typically containing sequential keyword-value pairs.
5764 @item @code{inputs} (default: @code{'()})
5765 @itemx @code{native-inputs} (default: @code{'()})
5766 @itemx @code{propagated-inputs} (default: @code{'()})
5767 @cindex inputs, of packages
5768 These fields list dependencies of the package. Each one is a list of
5769 tuples, where each tuple has a label for the input (a string) as its
5770 first element, a package, origin, or derivation as its second element,
5771 and optionally the name of the output thereof that should be used, which
5772 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5773 more on package outputs). For example, the list below specifies three
5777 `(("libffi" ,libffi)
5778 ("libunistring" ,libunistring)
5779 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5782 @cindex cross compilation, package dependencies
5783 The distinction between @code{native-inputs} and @code{inputs} is
5784 necessary when considering cross-compilation. When cross-compiling,
5785 dependencies listed in @code{inputs} are built for the @emph{target}
5786 architecture; conversely, dependencies listed in @code{native-inputs}
5787 are built for the architecture of the @emph{build} machine.
5789 @code{native-inputs} is typically used to list tools needed at
5790 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5791 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5792 this area (@pxref{Invoking guix lint}).
5794 @anchor{package-propagated-inputs}
5795 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5796 specified packages will be automatically installed alongside the package
5797 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5798 package}}, for information on how @command{guix package} deals with
5801 For example this is necessary when a C/C++ library needs headers of
5802 another library to compile, or when a pkg-config file refers to another
5803 one @i{via} its @code{Requires} field.
5805 Another example where @code{propagated-inputs} is useful is for languages
5806 that lack a facility to record the run-time search path akin to the
5807 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5808 more. To ensure that libraries written in those languages can find
5809 library code they depend on at run time, run-time dependencies must be
5810 listed in @code{propagated-inputs} rather than @code{inputs}.
5812 @item @code{outputs} (default: @code{'("out")})
5813 The list of output names of the package. @xref{Packages with Multiple
5814 Outputs}, for typical uses of additional outputs.
5816 @item @code{native-search-paths} (default: @code{'()})
5817 @itemx @code{search-paths} (default: @code{'()})
5818 A list of @code{search-path-specification} objects describing
5819 search-path environment variables honored by the package.
5821 @item @code{replacement} (default: @code{#f})
5822 This must be either @code{#f} or a package object that will be used as a
5823 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5826 @item @code{synopsis}
5827 A one-line description of the package.
5829 @item @code{description}
5830 A more elaborate description of the package.
5832 @item @code{license}
5833 @cindex license, of packages
5834 The license of the package; a value from @code{(guix licenses)},
5835 or a list of such values.
5837 @item @code{home-page}
5838 The URL to the home-page of the package, as a string.
5840 @item @code{supported-systems} (default: @code{%supported-systems})
5841 The list of systems supported by the package, as strings of the form
5842 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5844 @item @code{location} (default: source location of the @code{package} form)
5845 The source location of the package. It is useful to override this when
5846 inheriting from another package, in which case this field is not
5847 automatically corrected.
5851 @deffn {Scheme Syntax} this-package
5852 When used in the @emph{lexical scope} of a package field definition, this
5853 identifier resolves to the package being defined.
5855 The example below shows how to add a package as a native input of itself when
5863 ;; When cross-compiled, Guile, for example, depends on
5864 ;; a native version of itself. Add it here.
5865 (native-inputs (if (%current-target-system)
5866 `(("self" ,this-package))
5870 It is an error to refer to @code{this-package} outside a package definition.
5873 @node origin Reference
5874 @subsection @code{origin} Reference
5876 This section summarizes all the options available in @code{origin}
5877 declarations (@pxref{Defining Packages}).
5879 @deftp {Data Type} origin
5880 This is the data type representing a source code origin.
5884 An object containing the URI of the source. The object type depends on
5885 the @code{method} (see below). For example, when using the
5886 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5887 values are: a URL represented as a string, or a list thereof.
5890 A procedure that handles the URI.
5895 @item @var{url-fetch} from @code{(guix download)}
5896 download a file from the HTTP, HTTPS, or FTP URL specified in the
5900 @item @var{git-fetch} from @code{(guix git-download)}
5901 clone the Git version control repository, and check out the revision
5902 specified in the @code{uri} field as a @code{git-reference} object; a
5903 @code{git-reference} looks like this:
5907 (url "https://git.savannah.gnu.org/git/hello.git")
5913 A bytevector containing the SHA-256 hash of the source. Typically the
5914 @code{base32} form is used here to generate the bytevector from a
5917 You can obtain this information using @code{guix download}
5918 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5921 @item @code{file-name} (default: @code{#f})
5922 The file name under which the source code should be saved. When this is
5923 @code{#f}, a sensible default value will be used in most cases. In case
5924 the source is fetched from a URL, the file name from the URL will be
5925 used. For version control checkouts, it is recommended to provide the
5926 file name explicitly because the default is not very descriptive.
5928 @item @code{patches} (default: @code{'()})
5929 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5930 file-like objects}) pointing to patches to be applied to the source.
5932 This list of patches must be unconditional. In particular, it cannot
5933 depend on the value of @code{%current-system} or
5934 @code{%current-target-system}.
5936 @item @code{snippet} (default: @code{#f})
5937 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5938 in the source directory. This is a convenient way to modify the source,
5939 sometimes more convenient than a patch.
5941 @item @code{patch-flags} (default: @code{'("-p1")})
5942 A list of command-line flags that should be passed to the @code{patch}
5945 @item @code{patch-inputs} (default: @code{#f})
5946 Input packages or derivations to the patching process. When this is
5947 @code{#f}, the usual set of inputs necessary for patching are provided,
5948 such as GNU@tie{}Patch.
5950 @item @code{modules} (default: @code{'()})
5951 A list of Guile modules that should be loaded during the patching
5952 process and while running the code in the @code{snippet} field.
5954 @item @code{patch-guile} (default: @code{#f})
5955 The Guile package that should be used in the patching process. When
5956 this is @code{#f}, a sensible default is used.
5962 @section Build Systems
5964 @cindex build system
5965 Each package definition specifies a @dfn{build system} and arguments for
5966 that build system (@pxref{Defining Packages}). This @code{build-system}
5967 field represents the build procedure of the package, as well as implicit
5968 dependencies of that build procedure.
5970 Build systems are @code{<build-system>} objects. The interface to
5971 create and manipulate them is provided by the @code{(guix build-system)}
5972 module, and actual build systems are exported by specific modules.
5974 @cindex bag (low-level package representation)
5975 Under the hood, build systems first compile package objects to
5976 @dfn{bags}. A @dfn{bag} is like a package, but with less
5977 ornamentation---in other words, a bag is a lower-level representation of
5978 a package, which includes all the inputs of that package, including some
5979 that were implicitly added by the build system. This intermediate
5980 representation is then compiled to a derivation (@pxref{Derivations}).
5982 Build systems accept an optional list of @dfn{arguments}. In package
5983 definitions, these are passed @i{via} the @code{arguments} field
5984 (@pxref{Defining Packages}). They are typically keyword arguments
5985 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5986 Guile Reference Manual}). The value of these arguments is usually
5987 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5988 by the daemon (@pxref{Derivations}).
5990 The main build system is @code{gnu-build-system}, which implements the
5991 standard build procedure for GNU and many other packages. It
5992 is provided by the @code{(guix build-system gnu)} module.
5994 @defvr {Scheme Variable} gnu-build-system
5995 @code{gnu-build-system} represents the GNU Build System, and variants
5996 thereof (@pxref{Configuration, configuration and makefile conventions,,
5997 standards, GNU Coding Standards}).
5999 @cindex build phases
6000 In a nutshell, packages using it are configured, built, and installed with
6001 the usual @code{./configure && make && make check && make install}
6002 command sequence. In practice, a few additional steps are often needed.
6003 All these steps are split up in separate @dfn{phases},
6004 notably@footnote{Please see the @code{(guix build gnu-build-system)}
6005 modules for more details about the build phases.}:
6009 Unpack the source tarball, and change the current directory to the
6010 extracted source tree. If the source is actually a directory, copy it
6011 to the build tree, and enter that directory.
6013 @item patch-source-shebangs
6014 Patch shebangs encountered in source files so they refer to the right
6015 store file names. For instance, this changes @code{#!/bin/sh} to
6016 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
6019 Run the @file{configure} script with a number of default options, such
6020 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
6021 by the @code{#:configure-flags} argument.
6024 Run @code{make} with the list of flags specified with
6025 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
6026 (the default), build with @code{make -j}.
6029 Run @code{make check}, or some other target specified with
6030 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
6031 @code{#:parallel-tests?} argument is true (the default), run @code{make
6035 Run @code{make install} with the flags listed in @code{#:make-flags}.
6037 @item patch-shebangs
6038 Patch shebangs on the installed executable files.
6041 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
6042 is false), copying them to the @code{debug} output when available
6043 (@pxref{Installing Debugging Files}).
6046 @vindex %standard-phases
6047 The build-side module @code{(guix build gnu-build-system)} defines
6048 @code{%standard-phases} as the default list of build phases.
6049 @code{%standard-phases} is a list of symbol/procedure pairs, where the
6050 procedure implements the actual phase.
6052 The list of phases used for a particular package can be changed with the
6053 @code{#:phases} parameter. For instance, passing:
6056 #:phases (modify-phases %standard-phases (delete 'configure))
6059 means that all the phases described above will be used, except the
6060 @code{configure} phase.
6062 In addition, this build system ensures that the ``standard'' environment
6063 for GNU packages is available. This includes tools such as GCC, libc,
6064 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
6065 build-system gnu)} module for a complete list). We call these the
6066 @dfn{implicit inputs} of a package, because package definitions do not
6067 have to mention them.
6070 Other @code{<build-system>} objects are defined to support other
6071 conventions and tools used by free software packages. They inherit most
6072 of @code{gnu-build-system}, and differ mainly in the set of inputs
6073 implicitly added to the build process, and in the list of phases
6074 executed. Some of these build systems are listed below.
6076 @defvr {Scheme Variable} ant-build-system
6077 This variable is exported by @code{(guix build-system ant)}. It
6078 implements the build procedure for Java packages that can be built with
6079 @url{https://ant.apache.org/, Ant build tool}.
6081 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
6082 provided by the @code{icedtea} package to the set of inputs. Different
6083 packages can be specified with the @code{#:ant} and @code{#:jdk}
6084 parameters, respectively.
6086 When the original package does not provide a suitable Ant build file,
6087 the parameter @code{#:jar-name} can be used to generate a minimal Ant
6088 build file @file{build.xml} with tasks to build the specified jar
6089 archive. In this case the parameter @code{#:source-dir} can be used to
6090 specify the source sub-directory, defaulting to ``src''.
6092 The @code{#:main-class} parameter can be used with the minimal ant
6093 buildfile to specify the main class of the resulting jar. This makes the
6094 jar file executable. The @code{#:test-include} parameter can be used to
6095 specify the list of junit tests to run. It defaults to
6096 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
6097 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
6098 because abstract classes cannot be run as tests.
6100 The parameter @code{#:build-target} can be used to specify the Ant task
6101 that should be run during the @code{build} phase. By default the
6102 ``jar'' task will be run.
6106 @defvr {Scheme Variable} android-ndk-build-system
6107 @cindex Android distribution
6108 @cindex Android NDK build system
6109 This variable is exported by @code{(guix build-system android-ndk)}. It
6110 implements a build procedure for Android NDK (native development kit)
6111 packages using a Guix-specific build process.
6113 The build system assumes that packages install their public interface
6114 (header) files to the subdirectory @file{include} of the @code{out} output and
6115 their libraries to the subdirectory @file{lib} the @code{out} output.
6117 It's also assumed that the union of all the dependencies of a package
6118 has no conflicting files.
6120 For the time being, cross-compilation is not supported - so right now
6121 the libraries and header files are assumed to be host tools.
6125 @defvr {Scheme Variable} asdf-build-system/source
6126 @defvrx {Scheme Variable} asdf-build-system/sbcl
6127 @defvrx {Scheme Variable} asdf-build-system/ecl
6129 These variables, exported by @code{(guix build-system asdf)}, implement
6130 build procedures for Common Lisp packages using
6131 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
6132 definition facility for Common Lisp programs and libraries.
6134 The @code{asdf-build-system/source} system installs the packages in
6135 source form, and can be loaded using any common lisp implementation, via
6136 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
6137 systems in the format which a particular implementation understands.
6138 These build systems can also be used to produce executable programs, or
6139 lisp images which contain a set of packages pre-loaded.
6141 The build system uses naming conventions. For binary packages, the
6142 package name should be prefixed with the lisp implementation, such as
6143 @code{sbcl-} for @code{asdf-build-system/sbcl}.
6145 Additionally, the corresponding source package should be labeled using
6146 the same convention as python packages (see @ref{Python Modules}), using
6147 the @code{cl-} prefix.
6149 For binary packages, each system should be defined as a Guix package.
6150 If one package @code{origin} contains several systems, package variants
6151 can be created in order to build all the systems. Source packages,
6152 which use @code{asdf-build-system/source}, may contain several systems.
6154 In order to create executable programs and images, the build-side
6155 procedures @code{build-program} and @code{build-image} can be used.
6156 They should be called in a build phase after the @code{create-symlinks}
6157 phase, so that the system which was just built can be used within the
6158 resulting image. @code{build-program} requires a list of Common Lisp
6159 expressions to be passed as the @code{#:entry-program} argument.
6161 If the system is not defined within its own @code{.asd} file of the same
6162 name, then the @code{#:asd-file} parameter should be used to specify
6163 which file the system is defined in. Furthermore, if the package
6164 defines a system for its tests in a separate file, it will be loaded
6165 before the tests are run if it is specified by the
6166 @code{#:test-asd-file} parameter. If it is not set, the files
6167 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
6168 and @code{test.asd} will be tried if they exist.
6170 If for some reason the package must be named in a different way than the
6171 naming conventions suggest, the @code{#:asd-system-name} parameter can
6172 be used to specify the name of the system.
6176 @defvr {Scheme Variable} cargo-build-system
6177 @cindex Rust programming language
6178 @cindex Cargo (Rust build system)
6179 This variable is exported by @code{(guix build-system cargo)}. It
6180 supports builds of packages using Cargo, the build tool of the
6181 @uref{https://www.rust-lang.org, Rust programming language}.
6183 It adds @code{rustc} and @code{cargo} to the set of inputs.
6184 A different Rust package can be specified with the @code{#:rust} parameter.
6186 Regular cargo dependencies should be added to the package definition via the
6187 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
6188 spec can be a package or a source definition. Note that the spec must
6189 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
6190 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
6191 should be added to the package definition via the
6192 @code{#:cargo-development-inputs} parameter.
6194 In its @code{configure} phase, this build system will make any source inputs
6195 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6196 parameters available to cargo. It will also remove an included
6197 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6198 @code{build} phase. The @code{install} phase installs any crate the binaries
6199 if they are defined by the crate.
6203 @defvr {Scheme Variable} copy-build-system
6204 This variable is exported by @code{(guix build-system copy)}. It
6205 supports builds of simple packages that don't require much compiling,
6206 mostly just moving files around.
6208 It adds much of the @code{gnu-build-system} packages to the set of
6209 inputs. Because of this, the @code{copy-build-system} does not require
6210 all the boilerplate code often needed for the
6211 @code{trivial-build-system}.
6213 To further simplify the file installation process, an
6214 @code{#:install-plan} argument is exposed to let the packager specify
6215 which files go where. The install plan is a list of @code{(@var{source}
6216 @var{target} [@var{filters}])}. @var{filters} are optional.
6219 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
6221 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
6222 @item Otherwise install @var{source} as @var{target}.
6225 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
6226 the trailing slash of @var{target} is implied with the same meaning
6229 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
6230 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
6231 @code{#:exclude-regexp}, only select files are installed depending on
6232 the filters. Each filters is specified by a list of strings.
6234 @item With @code{#:include}, install all the files which the path suffix matches
6235 at least one of the elements in the given list.
6236 @item With @code{#:include-regexp}, install all the files which the
6237 subpaths match at least one of the regular expressions in the given
6239 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
6240 are the complement of their inclusion counterpart. Without @code{#:include} flags,
6241 install all files but those matching the exclusion filters.
6242 If both inclusions and exclusions are specified, the exclusions are done
6243 on top of the inclusions.
6246 In all cases, the paths relative to @var{source} are preserved within
6253 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
6254 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
6255 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
6256 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
6257 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
6258 @file{share/my-app/sub/file}.
6259 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
6260 @file{share/my-app/file}.
6265 @cindex Clojure (programming language)
6266 @cindex simple Clojure build system
6267 @defvr {Scheme Variable} clojure-build-system
6268 This variable is exported by @code{(guix build-system clojure)}. It implements
6269 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6270 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6273 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6274 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6275 @code{#:zip} parameters, respectively.
6277 A list of source directories, test directories and jar names can be specified
6278 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6279 parameters, respectively. Compile directory and main class can be specified
6280 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6281 Other parameters are documented below.
6283 This build system is an extension of @code{ant-build-system}, but with the
6284 following phases changed:
6289 This phase calls @code{compile} in Clojure to compile source files and runs
6290 @command{jar} to create jars from both source files and compiled files
6291 according to the include list and exclude list specified in
6292 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6293 has priority over the include list. These lists consist of symbols
6294 representing Clojure libraries or the special keyword @code{#:all} representing
6295 all Clojure libraries found under the source directories. The parameter
6296 @code{#:omit-source?} decides if source should be included into the jars.
6299 This phase runs tests according to the include list and exclude list specified
6300 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6301 meanings are analogous to that of @code{#:aot-include} and
6302 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6303 stands for all Clojure libraries found under the test directories. The
6304 parameter @code{#:tests?} decides if tests should be run.
6307 This phase installs all jars built previously.
6310 Apart from the above, this build system also contains an additional phase:
6315 This phase installs all top-level files with base name matching
6316 @code{%doc-regex}. A different regex can be specified with the
6317 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6318 directories specified in @code{#:doc-dirs} are installed as well.
6322 @defvr {Scheme Variable} cmake-build-system
6323 This variable is exported by @code{(guix build-system cmake)}. It
6324 implements the build procedure for packages using the
6325 @url{https://www.cmake.org, CMake build tool}.
6327 It automatically adds the @code{cmake} package to the set of inputs.
6328 Which package is used can be specified with the @code{#:cmake}
6331 The @code{#:configure-flags} parameter is taken as a list of flags
6332 passed to the @command{cmake} command. The @code{#:build-type}
6333 parameter specifies in abstract terms the flags passed to the compiler;
6334 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6335 debugging information''), which roughly means that code is compiled with
6336 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6339 @defvr {Scheme Variable} dune-build-system
6340 This variable is exported by @code{(guix build-system dune)}. It
6341 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6342 tool for the OCaml programming language. It is implemented as an extension
6343 of the @code{ocaml-build-system} which is described below. As such, the
6344 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6347 It automatically adds the @code{dune} package to the set of inputs.
6348 Which package is used can be specified with the @code{#:dune}
6351 There is no @code{configure} phase because dune packages typically don't
6352 need to be configured. The @code{#:build-flags} parameter is taken as a
6353 list of flags passed to the @code{dune} command during the build.
6355 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6356 command instead of the more recent @code{dune} command while building
6357 a package. Its default value is @code{#f}.
6359 The @code{#:package} parameter can be passed to specify a package name, which
6360 is useful when a package contains multiple packages and you want to build
6361 only one of them. This is equivalent to passing the @code{-p} argument to
6365 @defvr {Scheme Variable} go-build-system
6366 This variable is exported by @code{(guix build-system go)}. It
6367 implements a build procedure for Go packages using the standard
6368 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6369 Go build mechanisms}.
6371 The user is expected to provide a value for the key @code{#:import-path}
6372 and, in some cases, @code{#:unpack-path}. The
6373 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6374 corresponds to the file system path expected by the package's build
6375 scripts and any referring packages, and provides a unique way to
6376 refer to a Go package. It is typically based on a combination of the
6377 package source code's remote URI and file system hierarchy structure. In
6378 some cases, you will need to unpack the package's source code to a
6379 different directory structure than the one indicated by the import path,
6380 and @code{#:unpack-path} should be used in such cases.
6382 Packages that provide Go libraries should install their source code into
6383 the built output. The key @code{#:install-source?}, which defaults to
6384 @code{#t}, controls whether or not the source code is installed. It can
6385 be set to @code{#f} for packages that only provide executable files.
6388 @defvr {Scheme Variable} glib-or-gtk-build-system
6389 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6390 is intended for use with packages making use of GLib or GTK+.
6392 This build system adds the following two phases to the ones defined by
6393 @code{gnu-build-system}:
6396 @item glib-or-gtk-wrap
6397 The phase @code{glib-or-gtk-wrap} ensures that programs in
6398 @file{bin/} are able to find GLib ``schemas'' and
6399 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6400 modules}. This is achieved by wrapping the programs in launch scripts
6401 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
6402 environment variables.
6404 It is possible to exclude specific package outputs from that wrapping
6405 process by listing their names in the
6406 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6407 when an output is known not to contain any GLib or GTK+ binaries, and
6408 where wrapping would gratuitously add a dependency of that output on
6411 @item glib-or-gtk-compile-schemas
6412 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6413 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6414 GSettings schemas} of GLib are compiled. Compilation is performed by the
6415 @command{glib-compile-schemas} program. It is provided by the package
6416 @code{glib:bin} which is automatically imported by the build system.
6417 The @code{glib} package providing @command{glib-compile-schemas} can be
6418 specified with the @code{#:glib} parameter.
6421 Both phases are executed after the @code{install} phase.
6424 @defvr {Scheme Variable} guile-build-system
6425 This build system is for Guile packages that consist exclusively of Scheme
6426 code and that are so lean that they don't even have a makefile, let alone a
6427 @file{configure} script. It compiles Scheme code using @command{guild
6428 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6429 installs the @file{.scm} and @file{.go} files in the right place. It also
6430 installs documentation.
6432 This build system supports cross-compilation by using the @code{--target}
6433 option of @command{guild compile}.
6435 Packages built with @code{guile-build-system} must provide a Guile package in
6436 their @code{native-inputs} field.
6439 @defvr {Scheme Variable} julia-build-system
6440 This variable is exported by @code{(guix build-system julia)}. It implements
6441 the build procedure used by @uref{https://julialang.org/, julia} packages,
6442 which essentially is similar to running @command{julia -e 'using Pkg;
6443 Pkg.add(package)'} in an environment where @code{JULIA_LOAD_PATH} contains the
6444 paths to all Julia package inputs. Tests are run not run.
6446 Julia packages require the source @code{file-name} to be the real name of the
6447 package, correctly capitalized.
6449 For packages requiring shared library dependencies, you may need to write the
6450 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6451 variable = /gnu/store/library.so} for each dependency, plus a void function
6452 @code{check_deps() = nothing}.
6454 Some older packages that aren't using @file{Package.toml} yet, will require
6455 this file to be created, too. The function @code{julia-create-package-toml}
6456 helps creating the file. You need to pass the outputs and the source of the
6457 package, it's name (the same as the @code{file-name} parameter), the package
6458 uuid, the package version, and a list of dependencies specified by their name
6462 @defvr {Scheme Variable} minify-build-system
6463 This variable is exported by @code{(guix build-system minify)}. It
6464 implements a minification procedure for simple JavaScript packages.
6466 It adds @code{uglify-js} to the set of inputs and uses it to compress
6467 all JavaScript files in the @file{src} directory. A different minifier
6468 package can be specified with the @code{#:uglify-js} parameter, but it
6469 is expected that the package writes the minified code to the standard
6472 When the input JavaScript files are not all located in the @file{src}
6473 directory, the parameter @code{#:javascript-files} can be used to
6474 specify a list of file names to feed to the minifier.
6477 @defvr {Scheme Variable} ocaml-build-system
6478 This variable is exported by @code{(guix build-system ocaml)}. It implements
6479 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6480 of choosing the correct set of commands to run for each package. OCaml
6481 packages can expect many different commands to be run. This build system will
6484 When the package has a @file{setup.ml} file present at the top-level, it will
6485 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6486 @code{ocaml setup.ml -install}. The build system will assume that this file
6487 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6488 care of setting the prefix and enabling tests if they are not disabled. You
6489 can pass configure and build flags with the @code{#:configure-flags} and
6490 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6491 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6492 bypass this system in the build and install phases.
6494 When the package has a @file{configure} file, it is assumed that it is a
6495 hand-made configure script that requires a different argument format than
6496 in the @code{gnu-build-system}. You can add more flags with the
6497 @code{#:configure-flags} key.
6499 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6500 @code{#t}), it will be used and more flags can be passed to the build and
6501 install phases with the @code{#:make-flags} key.
6503 Finally, some packages do not have these files and use a somewhat standard
6504 location for its build system. In that case, the build system will run
6505 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6506 providing the path to the required findlib module. Additional flags can
6507 be passed via the @code{#:build-flags} key. Install is taken care of by
6508 @command{opam-installer}. In this case, the @code{opam} package must
6509 be added to the @code{native-inputs} field of the package definition.
6511 Note that most OCaml packages assume they will be installed in the same
6512 directory as OCaml, which is not what we want in guix. In particular, they
6513 will install @file{.so} files in their module's directory, which is usually
6514 fine because it is in the OCaml compiler directory. In guix though, these
6515 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6516 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6517 @file{.so} libraries should be installed.
6520 @defvr {Scheme Variable} python-build-system
6521 This variable is exported by @code{(guix build-system python)}. It
6522 implements the more or less standard build procedure used by Python
6523 packages, which consists in running @code{python setup.py build} and
6524 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6526 For packages that install stand-alone Python programs under @code{bin/},
6527 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6528 environment variable points to all the Python libraries they depend on.
6530 Which Python package is used to perform the build can be specified with
6531 the @code{#:python} parameter. This is a useful way to force a package
6532 to be built for a specific version of the Python interpreter, which
6533 might be necessary if the package is only compatible with a single
6534 interpreter version.
6536 By default guix calls @code{setup.py} under control of
6537 @code{setuptools}, much like @command{pip} does. Some packages are not
6538 compatible with setuptools (and pip), thus you can disable this by
6539 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6542 @defvr {Scheme Variable} perl-build-system
6543 This variable is exported by @code{(guix build-system perl)}. It
6544 implements the standard build procedure for Perl packages, which either
6545 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6546 followed by @code{Build} and @code{Build install}; or in running
6547 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6548 @code{make} and @code{make install}, depending on which of
6549 @code{Build.PL} or @code{Makefile.PL} is present in the package
6550 distribution. Preference is given to the former if both @code{Build.PL}
6551 and @code{Makefile.PL} exist in the package distribution. This
6552 preference can be reversed by specifying @code{#t} for the
6553 @code{#:make-maker?} parameter.
6555 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6556 passes flags specified by the @code{#:make-maker-flags} or
6557 @code{#:module-build-flags} parameter, respectively.
6559 Which Perl package is used can be specified with @code{#:perl}.
6562 @defvr {Scheme Variable} qt-build-system
6563 This variable is exported by @code{(guix build-system qt)}. It
6564 is intended for use with applications using Qt or KDE.
6566 This build system adds the following two phases to the ones defined by
6567 @code{cmake-build-system}:
6571 The phase @code{check-setup} prepares the environment for running
6572 the checks as commonly used by Qt test programs.
6573 For now this only sets some environment variables:
6574 @code{QT_QPA_PLATFORM=offscreen},
6575 @code{DBUS_FATAL_WARNINGS=0} and
6576 @code{CTEST_OUTPUT_ON_FAILURE=1}.
6578 This phase is added before the @code{check} phase.
6579 It's a separate phase to ease adjusting if necessary.
6582 The phase @code{qt-wrap}
6583 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
6584 and output. In case some path is found, all programs in the output's
6585 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
6586 are wrapped in scripts defining the necessary environment variables.
6588 It is possible to exclude specific package outputs from that wrapping process
6589 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
6590 This is useful when an output is known not to contain any Qt binaries, and
6591 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
6594 This phase is added after the @code{install} phase.
6598 @defvr {Scheme Variable} r-build-system
6599 This variable is exported by @code{(guix build-system r)}. It
6600 implements the build procedure used by @uref{https://r-project.org, R}
6601 packages, which essentially is little more than running @code{R CMD
6602 INSTALL --library=/gnu/store/@dots{}} in an environment where
6603 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6604 are run after installation using the R function
6605 @code{tools::testInstalledPackage}.
6608 @defvr {Scheme Variable} rakudo-build-system
6609 This variable is exported by @code{(guix build-system rakudo)}. It
6610 implements the build procedure used by @uref{https://rakudo.org/,
6611 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6612 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6613 installs the binaries, library files and the resources, as well as wrap
6614 the files under the @code{bin/} directory. Tests can be skipped by
6615 passing @code{#f} to the @code{tests?} parameter.
6617 Which rakudo package is used can be specified with @code{rakudo}.
6618 Which perl6-tap-harness package used for the tests can be specified with
6619 @code{#:prove6} or removed by passing @code{#f} to the
6620 @code{with-prove6?} parameter.
6621 Which perl6-zef package used for tests and installing can be specified
6622 with @code{#:zef} or removed by passing @code{#f} to the
6623 @code{with-zef?} parameter.
6626 @defvr {Scheme Variable} texlive-build-system
6627 This variable is exported by @code{(guix build-system texlive)}. It is
6628 used to build TeX packages in batch mode with a specified engine. The
6629 build system sets the @code{TEXINPUTS} variable to find all TeX source
6630 files in the inputs.
6632 By default it runs @code{luatex} on all files ending on @code{ins}. A
6633 different engine and format can be specified with the
6634 @code{#:tex-format} argument. Different build targets can be specified
6635 with the @code{#:build-targets} argument, which expects a list of file
6636 names. The build system adds only @code{texlive-bin} and
6637 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6638 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6639 and @code{#:texlive-latex-base}, respectively.
6641 The @code{#:tex-directory} parameter tells the build system where to
6642 install the built files under the texmf tree.
6645 @defvr {Scheme Variable} ruby-build-system
6646 This variable is exported by @code{(guix build-system ruby)}. It
6647 implements the RubyGems build procedure used by Ruby packages, which
6648 involves running @code{gem build} followed by @code{gem install}.
6650 The @code{source} field of a package that uses this build system
6651 typically references a gem archive, since this is the format that Ruby
6652 developers use when releasing their software. The build system unpacks
6653 the gem archive, potentially patches the source, runs the test suite,
6654 repackages the gem, and installs it. Additionally, directories and
6655 tarballs may be referenced to allow building unreleased gems from Git or
6656 a traditional source release tarball.
6658 Which Ruby package is used can be specified with the @code{#:ruby}
6659 parameter. A list of additional flags to be passed to the @command{gem}
6660 command can be specified with the @code{#:gem-flags} parameter.
6663 @defvr {Scheme Variable} waf-build-system
6664 This variable is exported by @code{(guix build-system waf)}. It
6665 implements a build procedure around the @code{waf} script. The common
6666 phases---@code{configure}, @code{build}, and @code{install}---are
6667 implemented by passing their names as arguments to the @code{waf}
6670 The @code{waf} script is executed by the Python interpreter. Which
6671 Python package is used to run the script can be specified with the
6672 @code{#:python} parameter.
6675 @defvr {Scheme Variable} scons-build-system
6676 This variable is exported by @code{(guix build-system scons)}. It
6677 implements the build procedure used by the SCons software construction
6678 tool. This build system runs @code{scons} to build the package,
6679 @code{scons test} to run tests, and then @code{scons install} to install
6682 Additional flags to be passed to @code{scons} can be specified with the
6683 @code{#:scons-flags} parameter. The default build and install targets
6684 can be overridden with @code{#:build-targets} and
6685 @code{#:install-targets} respectively. The version of Python used to
6686 run SCons can be specified by selecting the appropriate SCons package
6687 with the @code{#:scons} parameter.
6690 @defvr {Scheme Variable} haskell-build-system
6691 This variable is exported by @code{(guix build-system haskell)}. It
6692 implements the Cabal build procedure used by Haskell packages, which
6693 involves running @code{runhaskell Setup.hs configure
6694 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6695 Instead of installing the package by running @code{runhaskell Setup.hs
6696 install}, to avoid trying to register libraries in the read-only
6697 compiler store directory, the build system uses @code{runhaskell
6698 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6699 addition, the build system generates the package documentation by
6700 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6701 is passed. Optional Haddock parameters can be passed with the help of
6702 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6703 not found, the build system looks for @code{Setup.lhs} instead.
6705 Which Haskell compiler is used can be specified with the @code{#:haskell}
6706 parameter which defaults to @code{ghc}.
6709 @defvr {Scheme Variable} dub-build-system
6710 This variable is exported by @code{(guix build-system dub)}. It
6711 implements the Dub build procedure used by D packages, which
6712 involves running @code{dub build} and @code{dub run}.
6713 Installation is done by copying the files manually.
6715 Which D compiler is used can be specified with the @code{#:ldc}
6716 parameter which defaults to @code{ldc}.
6719 @defvr {Scheme Variable} emacs-build-system
6720 This variable is exported by @code{(guix build-system emacs)}. It
6721 implements an installation procedure similar to the packaging system
6722 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6724 It first creates the @code{@code{package}-autoloads.el} file, then it
6725 byte compiles all Emacs Lisp files. Differently from the Emacs
6726 packaging system, the Info documentation files are moved to the standard
6727 documentation directory and the @file{dir} file is deleted. The Elisp
6728 package files are installed directly under @file{share/emacs/site-lisp}.
6731 @defvr {Scheme Variable} font-build-system
6732 This variable is exported by @code{(guix build-system font)}. It
6733 implements an installation procedure for font packages where upstream
6734 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6735 need to be copied into place. It copies font files to standard
6736 locations in the output directory.
6739 @defvr {Scheme Variable} meson-build-system
6740 This variable is exported by @code{(guix build-system meson)}. It
6741 implements the build procedure for packages that use
6742 @url{https://mesonbuild.com, Meson} as their build system.
6744 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6745 of inputs, and they can be changed with the parameters @code{#:meson}
6746 and @code{#:ninja} if needed. The default Meson is
6747 @code{meson-for-build}, which is special because it doesn't clear the
6748 @code{RUNPATH} of binaries and libraries when they are installed.
6750 This build system is an extension of @code{gnu-build-system}, but with the
6751 following phases changed to some specific for Meson:
6756 The phase runs @code{meson} with the flags specified in
6757 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6758 @code{plain} unless something else is specified in @code{#:build-type}.
6761 The phase runs @code{ninja} to build the package in parallel by default, but
6762 this can be changed with @code{#:parallel-build?}.
6765 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6766 which is @code{"test"} by default.
6769 The phase runs @code{ninja install} and can not be changed.
6772 Apart from that, the build system also adds the following phases:
6777 This phase ensures that all binaries can find the libraries they need.
6778 It searches for required libraries in subdirectories of the package being
6779 built, and adds those to @code{RUNPATH} where needed. It also removes
6780 references to libraries left over from the build phase by
6781 @code{meson-for-build}, such as test dependencies, that aren't actually
6782 required for the program to run.
6784 @item glib-or-gtk-wrap
6785 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6786 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6788 @item glib-or-gtk-compile-schemas
6789 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6790 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6794 @defvr {Scheme Variable} linux-module-build-system
6795 @code{linux-module-build-system} allows building Linux kernel modules.
6797 @cindex build phases
6798 This build system is an extension of @code{gnu-build-system}, but with the
6799 following phases changed:
6804 This phase configures the environment so that the Linux kernel's Makefile
6805 can be used to build the external kernel module.
6808 This phase uses the Linux kernel's Makefile in order to build the external
6812 This phase uses the Linux kernel's Makefile in order to install the external
6816 It is possible and useful to specify the Linux kernel to use for building
6817 the module (in the @code{arguments} form of a package using the
6818 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
6821 @defvr {Scheme Variable} node-build-system
6822 This variable is exported by @code{(guix build-system node)}. It
6823 implements the build procedure used by @uref{https://nodejs.org,
6824 Node.js}, which implements an approximation of the @code{npm install}
6825 command, followed by an @code{npm test} command.
6827 Which Node.js package is used to interpret the @code{npm} commands can
6828 be specified with the @code{#:node} parameter which defaults to
6832 Lastly, for packages that do not need anything as sophisticated, a
6833 ``trivial'' build system is provided. It is trivial in the sense that
6834 it provides basically no support: it does not pull any implicit inputs,
6835 and does not have a notion of build phases.
6837 @defvr {Scheme Variable} trivial-build-system
6838 This variable is exported by @code{(guix build-system trivial)}.
6840 This build system requires a @code{#:builder} argument. This argument
6841 must be a Scheme expression that builds the package output(s)---as
6842 with @code{build-expression->derivation} (@pxref{Derivations,
6843 @code{build-expression->derivation}}).
6853 Conceptually, the @dfn{store} is the place where derivations that have
6854 been built successfully are stored---by default, @file{/gnu/store}.
6855 Sub-directories in the store are referred to as @dfn{store items} or
6856 sometimes @dfn{store paths}. The store has an associated database that
6857 contains information such as the store paths referred to by each store
6858 path, and the list of @emph{valid} store items---results of successful
6859 builds. This database resides in @file{@var{localstatedir}/guix/db},
6860 where @var{localstatedir} is the state directory specified @i{via}
6861 @option{--localstatedir} at configure time, usually @file{/var}.
6863 The store is @emph{always} accessed by the daemon on behalf of its clients
6864 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6865 connect to the daemon over a Unix-domain socket, send requests to it,
6866 and read the result---these are remote procedure calls, or RPCs.
6869 Users must @emph{never} modify files under @file{/gnu/store} directly.
6870 This would lead to inconsistencies and break the immutability
6871 assumptions of Guix's functional model (@pxref{Introduction}).
6873 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6874 how to check the integrity of the store and attempt recovery from
6875 accidental modifications.
6878 The @code{(guix store)} module provides procedures to connect to the
6879 daemon, and to perform RPCs. These are described below. By default,
6880 @code{open-connection}, and thus all the @command{guix} commands,
6881 connect to the local daemon or to the URI specified by the
6882 @code{GUIX_DAEMON_SOCKET} environment variable.
6884 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6885 When set, the value of this variable should be a file name or a URI
6886 designating the daemon endpoint. When it is a file name, it denotes a
6887 Unix-domain socket to connect to. In addition to file names, the
6888 supported URI schemes are:
6893 These are for Unix-domain sockets.
6894 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6895 @file{/var/guix/daemon-socket/socket}.
6898 @cindex daemon, remote access
6899 @cindex remote access to the daemon
6900 @cindex daemon, cluster setup
6901 @cindex clusters, daemon setup
6902 These URIs denote connections over TCP/IP, without encryption nor
6903 authentication of the remote host. The URI must specify the host name
6904 and optionally a port number (by default port 44146 is used):
6907 guix://master.guix.example.org:1234
6910 This setup is suitable on local networks, such as clusters, where only
6911 trusted nodes may connect to the build daemon at
6912 @code{master.guix.example.org}.
6914 The @code{--listen} option of @command{guix-daemon} can be used to
6915 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6919 @cindex SSH access to build daemons
6920 These URIs allow you to connect to a remote daemon over SSH. This
6921 feature requires Guile-SSH (@pxref{Requirements}) and a working
6922 @code{guile} binary in @code{PATH} on the destination machine. It
6923 supports public key and GSSAPI authentication. A typical URL might look
6927 ssh://charlie@@guix.example.org:22
6930 As for @command{guix copy}, the usual OpenSSH client configuration files
6931 are honored (@pxref{Invoking guix copy}).
6934 Additional URI schemes may be supported in the future.
6936 @c XXX: Remove this note when the protocol incurs fewer round trips
6937 @c and when (guix derivations) no longer relies on file system access.
6939 The ability to connect to remote build daemons is considered
6940 experimental as of @value{VERSION}. Please get in touch with us to
6941 share any problems or suggestions you may have (@pxref{Contributing}).
6945 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6946 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6947 @var{reserve-space?} is true, instruct it to reserve a little bit of
6948 extra space on the file system so that the garbage collector can still
6949 operate should the disk become full. Return a server object.
6951 @var{file} defaults to @code{%default-socket-path}, which is the normal
6952 location given the options that were passed to @command{configure}.
6955 @deffn {Scheme Procedure} close-connection @var{server}
6956 Close the connection to @var{server}.
6959 @defvr {Scheme Variable} current-build-output-port
6960 This variable is bound to a SRFI-39 parameter, which refers to the port
6961 where build and error logs sent by the daemon should be written.
6964 Procedures that make RPCs all take a server object as their first
6967 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6968 @cindex invalid store items
6969 Return @code{#t} when @var{path} designates a valid store item and
6970 @code{#f} otherwise (an invalid item may exist on disk but still be
6971 invalid, for instance because it is the result of an aborted or failed
6974 A @code{&store-protocol-error} condition is raised if @var{path} is not
6975 prefixed by the store directory (@file{/gnu/store}).
6978 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6979 Add @var{text} under file @var{name} in the store, and return its store
6980 path. @var{references} is the list of store paths referred to by the
6981 resulting store path.
6984 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6986 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6987 file names, or derivation/output pairs, using the specified
6988 @var{mode}---@code{(build-mode normal)} by default.
6991 Note that the @code{(guix monads)} module provides a monad as well as
6992 monadic versions of the above procedures, with the goal of making it
6993 more convenient to work with code that accesses the store (@pxref{The
6997 @i{This section is currently incomplete.}
7000 @section Derivations
7003 Low-level build actions and the environment in which they are performed
7004 are represented by @dfn{derivations}. A derivation contains the
7005 following pieces of information:
7009 The outputs of the derivation---derivations produce at least one file or
7010 directory in the store, but may produce more.
7013 @cindex build-time dependencies
7014 @cindex dependencies, build-time
7015 The inputs of the derivations---i.e., its build-time dependencies---which may
7016 be other derivations or plain files in the store (patches, build scripts,
7020 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
7023 The file name of a build script in the store, along with the arguments
7027 A list of environment variables to be defined.
7031 @cindex derivation path
7032 Derivations allow clients of the daemon to communicate build actions to
7033 the store. They exist in two forms: as an in-memory representation,
7034 both on the client- and daemon-side, and as files in the store whose
7035 name end in @code{.drv}---these files are referred to as @dfn{derivation
7036 paths}. Derivations paths can be passed to the @code{build-derivations}
7037 procedure to perform the build actions they prescribe (@pxref{The
7040 @cindex fixed-output derivations
7041 Operations such as file downloads and version-control checkouts for
7042 which the expected content hash is known in advance are modeled as
7043 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
7044 of a fixed-output derivation are independent of its inputs---e.g., a
7045 source code download produces the same result regardless of the download
7046 method and tools being used.
7049 @cindex run-time dependencies
7050 @cindex dependencies, run-time
7051 The outputs of derivations---i.e., the build results---have a set of
7052 @dfn{references}, as reported by the @code{references} RPC or the
7053 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
7054 are the set of run-time dependencies of the build results. References are a
7055 subset of the inputs of the derivation; this subset is automatically computed
7056 by the build daemon by scanning all the files in the outputs.
7058 The @code{(guix derivations)} module provides a representation of
7059 derivations as Scheme objects, along with procedures to create and
7060 otherwise manipulate derivations. The lowest-level primitive to create
7061 a derivation is the @code{derivation} procedure:
7063 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
7064 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7065 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
7066 [#:system (%current-system)] [#:references-graphs #f] @
7067 [#:allowed-references #f] [#:disallowed-references #f] @
7068 [#:leaked-env-vars #f] [#:local-build? #f] @
7069 [#:substitutable? #t] [#:properties '()]
7070 Build a derivation with the given arguments, and return the resulting
7071 @code{<derivation>} object.
7073 When @var{hash} and @var{hash-algo} are given, a
7074 @dfn{fixed-output derivation} is created---i.e., one whose result is
7075 known in advance, such as a file download. If, in addition,
7076 @var{recursive?} is true, then that fixed output may be an executable
7077 file or a directory and @var{hash} must be the hash of an archive
7078 containing this output.
7080 When @var{references-graphs} is true, it must be a list of file
7081 name/store path pairs. In that case, the reference graph of each store
7082 path is exported in the build environment in the corresponding file, in
7083 a simple text format.
7085 When @var{allowed-references} is true, it must be a list of store items
7086 or outputs that the derivation's output may refer to. Likewise,
7087 @var{disallowed-references}, if true, must be a list of things the
7088 outputs may @emph{not} refer to.
7090 When @var{leaked-env-vars} is true, it must be a list of strings
7091 denoting environment variables that are allowed to ``leak'' from the
7092 daemon's environment to the build environment. This is only applicable
7093 to fixed-output derivations---i.e., when @var{hash} is true. The main
7094 use is to allow variables such as @code{http_proxy} to be passed to
7095 derivations that download files.
7097 When @var{local-build?} is true, declare that the derivation is not a
7098 good candidate for offloading and should rather be built locally
7099 (@pxref{Daemon Offload Setup}). This is the case for small derivations
7100 where the costs of data transfers would outweigh the benefits.
7102 When @var{substitutable?} is false, declare that substitutes of the
7103 derivation's output should not be used (@pxref{Substitutes}). This is
7104 useful, for instance, when building packages that capture details of the
7105 host CPU instruction set.
7107 @var{properties} must be an association list describing ``properties'' of the
7108 derivation. It is kept as-is, uninterpreted, in the derivation.
7112 Here's an example with a shell script as its builder, assuming
7113 @var{store} is an open connection to the daemon, and @var{bash} points
7114 to a Bash executable in the store:
7117 (use-modules (guix utils)
7121 (let ((builder ; add the Bash script to the store
7122 (add-text-to-store store "my-builder.sh"
7123 "echo hello world > $out\n" '())))
7124 (derivation store "foo"
7125 bash `("-e" ,builder)
7126 #:inputs `((,bash) (,builder))
7127 #:env-vars '(("HOME" . "/homeless"))))
7128 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
7131 As can be guessed, this primitive is cumbersome to use directly. A
7132 better approach is to write build scripts in Scheme, of course! The
7133 best course of action for that is to write the build code as a
7134 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
7135 information, @pxref{G-Expressions}.
7137 Once upon a time, @code{gexp->derivation} did not exist and constructing
7138 derivations with build code written in Scheme was achieved with
7139 @code{build-expression->derivation}, documented below. This procedure
7140 is now deprecated in favor of the much nicer @code{gexp->derivation}.
7142 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
7143 @var{name} @var{exp} @
7144 [#:system (%current-system)] [#:inputs '()] @
7145 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7146 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7147 [#:references-graphs #f] [#:allowed-references #f] @
7148 [#:disallowed-references #f] @
7149 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
7150 Return a derivation that executes Scheme expression @var{exp} as a
7151 builder for derivation @var{name}. @var{inputs} must be a list of
7152 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
7153 @code{"out"} is assumed. @var{modules} is a list of names of Guile
7154 modules from the current search path to be copied in the store,
7155 compiled, and made available in the load path during the execution of
7156 @var{exp}---e.g., @code{((guix build utils) (guix build
7157 gnu-build-system))}.
7159 @var{exp} is evaluated in an environment where @code{%outputs} is bound
7160 to a list of output/path pairs, and where @code{%build-inputs} is bound
7161 to a list of string/output-path pairs made from @var{inputs}.
7162 Optionally, @var{env-vars} is a list of string pairs specifying the name
7163 and value of environment variables visible to the builder. The builder
7164 terminates by passing the result of @var{exp} to @code{exit}; thus, when
7165 @var{exp} returns @code{#f}, the build is considered to have failed.
7167 @var{exp} is built using @var{guile-for-build} (a derivation). When
7168 @var{guile-for-build} is omitted or is @code{#f}, the value of the
7169 @code{%guile-for-build} fluid is used instead.
7171 See the @code{derivation} procedure for the meaning of
7172 @var{references-graphs}, @var{allowed-references},
7173 @var{disallowed-references}, @var{local-build?}, and
7174 @var{substitutable?}.
7178 Here's an example of a single-output derivation that creates a directory
7179 containing one file:
7182 (let ((builder '(let ((out (assoc-ref %outputs "out")))
7183 (mkdir out) ; create /gnu/store/@dots{}-goo
7184 (call-with-output-file (string-append out "/test")
7186 (display '(hello guix) p))))))
7187 (build-expression->derivation store "goo" builder))
7189 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
7193 @node The Store Monad
7194 @section The Store Monad
7198 The procedures that operate on the store described in the previous
7199 sections all take an open connection to the build daemon as their first
7200 argument. Although the underlying model is functional, they either have
7201 side effects or depend on the current state of the store.
7203 The former is inconvenient: the connection to the build daemon has to be
7204 carried around in all those functions, making it impossible to compose
7205 functions that do not take that parameter with functions that do. The
7206 latter can be problematic: since store operations have side effects
7207 and/or depend on external state, they have to be properly sequenced.
7209 @cindex monadic values
7210 @cindex monadic functions
7211 This is where the @code{(guix monads)} module comes in. This module
7212 provides a framework for working with @dfn{monads}, and a particularly
7213 useful monad for our uses, the @dfn{store monad}. Monads are a
7214 construct that allows two things: associating ``context'' with values
7215 (in our case, the context is the store), and building sequences of
7216 computations (here computations include accesses to the store). Values
7217 in a monad---values that carry this additional context---are called
7218 @dfn{monadic values}; procedures that return such values are called
7219 @dfn{monadic procedures}.
7221 Consider this ``normal'' procedure:
7224 (define (sh-symlink store)
7225 ;; Return a derivation that symlinks the 'bash' executable.
7226 (let* ((drv (package-derivation store bash))
7227 (out (derivation->output-path drv))
7228 (sh (string-append out "/bin/bash")))
7229 (build-expression->derivation store "sh"
7230 `(symlink ,sh %output))))
7233 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
7234 as a monadic function:
7237 (define (sh-symlink)
7238 ;; Same, but return a monadic value.
7239 (mlet %store-monad ((drv (package->derivation bash)))
7240 (gexp->derivation "sh"
7241 #~(symlink (string-append #$drv "/bin/bash")
7245 There are several things to note in the second version: the @code{store}
7246 parameter is now implicit and is ``threaded'' in the calls to the
7247 @code{package->derivation} and @code{gexp->derivation} monadic
7248 procedures, and the monadic value returned by @code{package->derivation}
7249 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
7251 As it turns out, the call to @code{package->derivation} can even be
7252 omitted since it will take place implicitly, as we will see later
7253 (@pxref{G-Expressions}):
7256 (define (sh-symlink)
7257 (gexp->derivation "sh"
7258 #~(symlink (string-append #$bash "/bin/bash")
7263 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
7264 @c for the funny quote.
7265 Calling the monadic @code{sh-symlink} has no effect. As someone once
7266 said, ``you exit a monad like you exit a building on fire: by running''.
7267 So, to exit the monad and get the desired effect, one must use
7268 @code{run-with-store}:
7271 (run-with-store (open-connection) (sh-symlink))
7272 @result{} /gnu/store/...-sh-symlink
7275 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
7276 new ``meta-commands'' to make it easier to deal with monadic procedures:
7277 @code{run-in-store}, and @code{enter-store-monad}. The former is used
7278 to ``run'' a single monadic value through the store:
7281 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
7282 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7285 The latter enters a recursive REPL, where all the return values are
7286 automatically run through the store:
7289 scheme@@(guile-user)> ,enter-store-monad
7290 store-monad@@(guile-user) [1]> (package->derivation hello)
7291 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7292 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
7293 $3 = "/gnu/store/@dots{}-foo"
7294 store-monad@@(guile-user) [1]> ,q
7295 scheme@@(guile-user)>
7299 Note that non-monadic values cannot be returned in the
7300 @code{store-monad} REPL.
7302 The main syntactic forms to deal with monads in general are provided by
7303 the @code{(guix monads)} module and are described below.
7305 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7306 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7310 @deffn {Scheme Syntax} return @var{val}
7311 Return a monadic value that encapsulates @var{val}.
7314 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7315 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7316 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7317 referred to as ``bind'', but that name denotes an unrelated procedure in
7318 Guile. Thus we use this somewhat cryptic symbol inherited from the
7319 Haskell language.}. There can be one @var{mproc} or several of them, as
7324 (with-monad %state-monad
7326 (lambda (x) (return (+ 1 x)))
7327 (lambda (x) (return (* 2 x)))))
7331 @result{} some-state
7335 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7337 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7339 Bind the variables @var{var} to the monadic values @var{mval} in
7340 @var{body}, which is a sequence of expressions. As with the bind
7341 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7342 value ``contained'' in @var{mval} and making @var{var} refer to that
7343 raw, non-monadic value within the scope of the @var{body}. The form
7344 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7345 @var{val}, as per @code{let}. The binding operations occur in sequence
7346 from left to right. The last expression of @var{body} must be a monadic
7347 expression, and its result will become the result of the @code{mlet} or
7348 @code{mlet*} when run in the @var{monad}.
7350 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7351 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7354 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7355 Bind @var{mexp} and the following monadic expressions in sequence,
7356 returning the result of the last expression. Every expression in the
7357 sequence must be a monadic expression.
7359 This is akin to @code{mlet}, except that the return values of the
7360 monadic expressions are ignored. In that sense, it is analogous to
7361 @code{begin}, but applied to monadic expressions.
7364 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7365 When @var{condition} is true, evaluate the sequence of monadic
7366 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7367 @var{condition} is false, return @code{*unspecified*} in the current
7368 monad. Every expression in the sequence must be a monadic expression.
7371 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7372 When @var{condition} is false, evaluate the sequence of monadic
7373 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7374 @var{condition} is true, return @code{*unspecified*} in the current
7375 monad. Every expression in the sequence must be a monadic expression.
7379 The @code{(guix monads)} module provides the @dfn{state monad}, which
7380 allows an additional value---the state---to be @emph{threaded} through
7381 monadic procedure calls.
7383 @defvr {Scheme Variable} %state-monad
7384 The state monad. Procedures in the state monad can access and change
7385 the state that is threaded.
7387 Consider the example below. The @code{square} procedure returns a value
7388 in the state monad. It returns the square of its argument, but also
7389 increments the current state value:
7393 (mlet %state-monad ((count (current-state)))
7394 (mbegin %state-monad
7395 (set-current-state (+ 1 count))
7398 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7403 When ``run'' through @code{%state-monad}, we obtain that additional state
7404 value, which is the number of @code{square} calls.
7407 @deffn {Monadic Procedure} current-state
7408 Return the current state as a monadic value.
7411 @deffn {Monadic Procedure} set-current-state @var{value}
7412 Set the current state to @var{value} and return the previous state as a
7416 @deffn {Monadic Procedure} state-push @var{value}
7417 Push @var{value} to the current state, which is assumed to be a list,
7418 and return the previous state as a monadic value.
7421 @deffn {Monadic Procedure} state-pop
7422 Pop a value from the current state and return it as a monadic value.
7423 The state is assumed to be a list.
7426 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7427 Run monadic value @var{mval} starting with @var{state} as the initial
7428 state. Return two values: the resulting value, and the resulting state.
7431 The main interface to the store monad, provided by the @code{(guix
7432 store)} module, is as follows.
7434 @defvr {Scheme Variable} %store-monad
7435 The store monad---an alias for @code{%state-monad}.
7437 Values in the store monad encapsulate accesses to the store. When its
7438 effect is needed, a value of the store monad must be ``evaluated'' by
7439 passing it to the @code{run-with-store} procedure (see below.)
7442 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7443 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7444 open store connection.
7447 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7448 Return as a monadic value the absolute file name in the store of the file
7449 containing @var{text}, a string. @var{references} is a list of store items that the
7450 resulting text file refers to; it defaults to the empty list.
7453 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7454 Return as a monadic value the absolute file name in the store of the file
7455 containing @var{data}, a bytevector. @var{references} is a list of store
7456 items that the resulting binary file refers to; it defaults to the empty list.
7459 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7460 [#:recursive? #t] [#:select? (const #t)]
7461 Return the name of @var{file} once interned in the store. Use
7462 @var{name} as its store name, or the basename of @var{file} if
7463 @var{name} is omitted.
7465 When @var{recursive?} is true, the contents of @var{file} are added
7466 recursively; if @var{file} designates a flat file and @var{recursive?}
7467 is true, its contents are added, and its permission bits are kept.
7469 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7470 @var{stat})} for each directory entry, where @var{file} is the entry's
7471 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7472 entries for which @var{select?} does not return true.
7474 The example below adds a file to the store, under two different names:
7477 (run-with-store (open-connection)
7478 (mlet %store-monad ((a (interned-file "README"))
7479 (b (interned-file "README" "LEGU-MIN")))
7480 (return (list a b))))
7482 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7487 The @code{(guix packages)} module exports the following package-related
7490 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7491 [#:system (%current-system)] [#:target #f] @
7494 value in the absolute file name of @var{file} within the @var{output}
7495 directory of @var{package}. When @var{file} is omitted, return the name
7496 of the @var{output} directory of @var{package}. When @var{target} is
7497 true, use it as a cross-compilation target triplet.
7499 Note that this procedure does @emph{not} build @var{package}. Thus, the
7500 result might or might not designate an existing file. We recommend not
7501 using this procedure unless you know what you are doing.
7504 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7505 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7506 @var{target} [@var{system}]
7507 Monadic version of @code{package-derivation} and
7508 @code{package-cross-derivation} (@pxref{Defining Packages}).
7513 @section G-Expressions
7515 @cindex G-expression
7516 @cindex build code quoting
7517 So we have ``derivations'', which represent a sequence of build actions
7518 to be performed to produce an item in the store (@pxref{Derivations}).
7519 These build actions are performed when asking the daemon to actually
7520 build the derivations; they are run by the daemon in a container
7521 (@pxref{Invoking guix-daemon}).
7523 @cindex strata of code
7524 It should come as no surprise that we like to write these build actions
7525 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7526 code@footnote{The term @dfn{stratum} in this context was coined by
7527 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7528 Kiselyov, who has written insightful
7529 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7530 on this topic}, refers to this kind of code generation as
7531 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7532 to the daemon, etc.---and the ``build code''---code that actually
7533 performs build actions, such as making directories, invoking
7534 @command{make}, etc.
7536 To describe a derivation and its build actions, one typically needs to
7537 embed build code inside host code. It boils down to manipulating build
7538 code as data, and the homoiconicity of Scheme---code has a direct
7539 representation as data---comes in handy for that. But we need more than
7540 the normal @code{quasiquote} mechanism in Scheme to construct build
7543 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7544 S-expressions adapted to build expressions. G-expressions, or
7545 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7546 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7547 @code{#$}, and @code{#$@@}), which are comparable to
7548 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7549 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7550 GNU Guile Reference Manual}). However, there are major differences:
7554 Gexps are meant to be written to a file and run or manipulated by other
7558 When a high-level object such as a package or derivation is unquoted
7559 inside a gexp, the result is as if its output file name had been
7563 Gexps carry information about the packages or derivations they refer to,
7564 and these dependencies are automatically added as inputs to the build
7565 processes that use them.
7568 @cindex lowering, of high-level objects in gexps
7569 This mechanism is not limited to package and derivation
7570 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7571 derivations or files in the store can be defined,
7572 such that these objects can also be inserted
7573 into gexps. For example, a useful type of high-level objects that can be
7574 inserted in a gexp is ``file-like objects'', which make it easy to
7575 add files to the store and to refer to them in
7576 derivations and such (see @code{local-file} and @code{plain-file}
7579 To illustrate the idea, here is an example of a gexp:
7586 (symlink (string-append #$coreutils "/bin/ls")
7590 This gexp can be passed to @code{gexp->derivation}; we obtain a
7591 derivation that builds a directory containing exactly one symlink to
7592 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7595 (gexp->derivation "the-thing" build-exp)
7598 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7599 substituted to the reference to the @var{coreutils} package in the
7600 actual build code, and @var{coreutils} is automatically made an input to
7601 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7602 output)}) is replaced by a string containing the directory name of the
7603 output of the derivation.
7605 @cindex cross compilation
7606 In a cross-compilation context, it is useful to distinguish between
7607 references to the @emph{native} build of a package---that can run on the
7608 host---versus references to cross builds of a package. To that end, the
7609 @code{#+} plays the same role as @code{#$}, but is a reference to a
7610 native package build:
7613 (gexp->derivation "vi"
7616 (mkdir (string-append #$output "/bin"))
7617 (system* (string-append #+coreutils "/bin/ln")
7619 (string-append #$emacs "/bin/emacs")
7620 (string-append #$output "/bin/vi")))
7621 #:target "mips64el-linux-gnu")
7625 In the example above, the native build of @var{coreutils} is used, so
7626 that @command{ln} can actually run on the host; but then the
7627 cross-compiled build of @var{emacs} is referenced.
7629 @cindex imported modules, for gexps
7630 @findex with-imported-modules
7631 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7632 able to use certain Guile modules from the ``host environment'' in the
7633 gexp, so those modules should be imported in the ``build environment''.
7634 The @code{with-imported-modules} form allows you to express that:
7637 (let ((build (with-imported-modules '((guix build utils))
7639 (use-modules (guix build utils))
7640 (mkdir-p (string-append #$output "/bin"))))))
7641 (gexp->derivation "empty-dir"
7644 (display "success!\n")
7649 In this example, the @code{(guix build utils)} module is automatically
7650 pulled into the isolated build environment of our gexp, such that
7651 @code{(use-modules (guix build utils))} works as expected.
7653 @cindex module closure
7654 @findex source-module-closure
7655 Usually you want the @emph{closure} of the module to be imported---i.e.,
7656 the module itself and all the modules it depends on---rather than just
7657 the module; failing to do that, attempts to use the module will fail
7658 because of missing dependent modules. The @code{source-module-closure}
7659 procedure computes the closure of a module by looking at its source file
7660 headers, which comes in handy in this case:
7663 (use-modules (guix modules)) ;for 'source-module-closure'
7665 (with-imported-modules (source-module-closure
7666 '((guix build utils)
7668 (gexp->derivation "something-with-vms"
7670 (use-modules (guix build utils)
7675 @cindex extensions, for gexps
7676 @findex with-extensions
7677 In the same vein, sometimes you want to import not just pure-Scheme
7678 modules, but also ``extensions'' such as Guile bindings to C libraries
7679 or other ``full-blown'' packages. Say you need the @code{guile-json}
7680 package available on the build side, here's how you would do it:
7683 (use-modules (gnu packages guile)) ;for 'guile-json'
7685 (with-extensions (list guile-json)
7686 (gexp->derivation "something-with-json"
7688 (use-modules (json))
7692 The syntactic form to construct gexps is summarized below.
7694 @deffn {Scheme Syntax} #~@var{exp}
7695 @deffnx {Scheme Syntax} (gexp @var{exp})
7696 Return a G-expression containing @var{exp}. @var{exp} may contain one
7697 or more of the following forms:
7701 @itemx (ungexp @var{obj})
7702 Introduce a reference to @var{obj}. @var{obj} may have one of the
7703 supported types, for example a package or a
7704 derivation, in which case the @code{ungexp} form is replaced by its
7705 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7707 If @var{obj} is a list, it is traversed and references to supported
7708 objects are substituted similarly.
7710 If @var{obj} is another gexp, its contents are inserted and its
7711 dependencies are added to those of the containing gexp.
7713 If @var{obj} is another kind of object, it is inserted as is.
7715 @item #$@var{obj}:@var{output}
7716 @itemx (ungexp @var{obj} @var{output})
7717 This is like the form above, but referring explicitly to the
7718 @var{output} of @var{obj}---this is useful when @var{obj} produces
7719 multiple outputs (@pxref{Packages with Multiple Outputs}).
7722 @itemx #+@var{obj}:output
7723 @itemx (ungexp-native @var{obj})
7724 @itemx (ungexp-native @var{obj} @var{output})
7725 Same as @code{ungexp}, but produces a reference to the @emph{native}
7726 build of @var{obj} when used in a cross compilation context.
7728 @item #$output[:@var{output}]
7729 @itemx (ungexp output [@var{output}])
7730 Insert a reference to derivation output @var{output}, or to the main
7731 output when @var{output} is omitted.
7733 This only makes sense for gexps passed to @code{gexp->derivation}.
7736 @itemx (ungexp-splicing @var{lst})
7737 Like the above, but splices the contents of @var{lst} inside the
7741 @itemx (ungexp-native-splicing @var{lst})
7742 Like the above, but refers to native builds of the objects listed in
7747 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7748 of the @code{gexp?} type (see below.)
7751 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7752 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7753 in their execution environment.
7755 Each item in @var{modules} can be the name of a module, such as
7756 @code{(guix build utils)}, or it can be a module name, followed by an
7757 arrow, followed by a file-like object:
7760 `((guix build utils)
7762 ((guix config) => ,(scheme-file "config.scm"
7763 #~(define-module @dots{}))))
7767 In the example above, the first two modules are taken from the search
7768 path, and the last one is created from the given file-like object.
7770 This form has @emph{lexical} scope: it has an effect on the gexps
7771 directly defined in @var{body}@dots{}, but not on those defined, say, in
7772 procedures called from @var{body}@dots{}.
7775 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7776 Mark the gexps defined in @var{body}@dots{} as requiring
7777 @var{extensions} in their build and execution environment.
7778 @var{extensions} is typically a list of package objects such as those
7779 defined in the @code{(gnu packages guile)} module.
7781 Concretely, the packages listed in @var{extensions} are added to the
7782 load path while compiling imported modules in @var{body}@dots{}; they
7783 are also added to the load path of the gexp returned by
7787 @deffn {Scheme Procedure} gexp? @var{obj}
7788 Return @code{#t} if @var{obj} is a G-expression.
7791 G-expressions are meant to be written to disk, either as code building
7792 some derivation, or as plain files in the store. The monadic procedures
7793 below allow you to do that (@pxref{The Store Monad}, for more
7794 information about monads.)
7796 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7797 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7798 [#:hash #f] [#:hash-algo #f] @
7799 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7800 [#:module-path @code{%load-path}] @
7801 [#:effective-version "2.2"] @
7802 [#:references-graphs #f] [#:allowed-references #f] @
7803 [#:disallowed-references #f] @
7804 [#:leaked-env-vars #f] @
7805 [#:script-name (string-append @var{name} "-builder")] @
7806 [#:deprecation-warnings #f] @
7807 [#:local-build? #f] [#:substitutable? #t] @
7808 [#:properties '()] [#:guile-for-build #f]
7809 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7810 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7811 stored in a file called @var{script-name}. When @var{target} is true,
7812 it is used as the cross-compilation target triplet for packages referred
7815 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7817 make @var{modules} available in the evaluation context of @var{exp};
7818 @var{modules} is a list of names of Guile modules searched in
7819 @var{module-path} to be copied in the store, compiled, and made available in
7820 the load path during the execution of @var{exp}---e.g., @code{((guix
7821 build utils) (guix build gnu-build-system))}.
7823 @var{effective-version} determines the string to use when adding extensions of
7824 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7826 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7829 When @var{references-graphs} is true, it must be a list of tuples of one of the
7833 (@var{file-name} @var{package})
7834 (@var{file-name} @var{package} @var{output})
7835 (@var{file-name} @var{derivation})
7836 (@var{file-name} @var{derivation} @var{output})
7837 (@var{file-name} @var{store-item})
7840 The right-hand-side of each element of @var{references-graphs} is automatically made
7841 an input of the build process of @var{exp}. In the build environment, each
7842 @var{file-name} contains the reference graph of the corresponding item, in a simple
7845 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7846 In the latter case, the list denotes store items that the result is allowed to
7847 refer to. Any reference to another store item will lead to a build error.
7848 Similarly for @var{disallowed-references}, which can list items that must not be
7849 referenced by the outputs.
7851 @var{deprecation-warnings} determines whether to show deprecation warnings while
7852 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7854 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7857 @cindex file-like objects
7858 The @code{local-file}, @code{plain-file}, @code{computed-file},
7859 @code{program-file}, and @code{scheme-file} procedures below return
7860 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7861 these objects lead to a file in the store. Consider this G-expression:
7864 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7865 #$(local-file "/tmp/my-nscd.conf"))
7868 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7869 to the store. Once expanded, for instance @i{via}
7870 @code{gexp->derivation}, the G-expression refers to that copy under
7871 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7872 does not have any effect on what the G-expression does.
7873 @code{plain-file} can be used similarly; it differs in that the file
7874 content is directly passed as a string.
7876 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7877 [#:recursive? #f] [#:select? (const #t)]
7878 Return an object representing local file @var{file} to add to the store;
7879 this object can be used in a gexp. If @var{file} is a literal string
7880 denoting a relative file name, it is looked up relative to the source
7881 file where it appears; if @var{file} is not a literal string, it is
7882 looked up relative to the current working directory at run time.
7883 @var{file} will be added to the store under @var{name}--by default the
7884 base name of @var{file}.
7886 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7887 designates a flat file and @var{recursive?} is true, its contents are added, and its
7888 permission bits are kept.
7890 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7891 @var{stat})} for each directory entry, where @var{file} is the entry's
7892 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7893 entries for which @var{select?} does not return true.
7895 This is the declarative counterpart of the @code{interned-file} monadic
7896 procedure (@pxref{The Store Monad, @code{interned-file}}).
7899 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7900 Return an object representing a text file called @var{name} with the given
7901 @var{content} (a string or a bytevector) to be added to the store.
7903 This is the declarative counterpart of @code{text-file}.
7906 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7907 [#:options '(#:local-build? #t)]
7908 Return an object representing the store item @var{name}, a file or
7909 directory computed by @var{gexp}. @var{options}
7910 is a list of additional arguments to pass to @code{gexp->derivation}.
7912 This is the declarative counterpart of @code{gexp->derivation}.
7915 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7916 [#:guile (default-guile)] [#:module-path %load-path] @
7917 [#:system (%current-system)] [#:target #f]
7918 Return an executable script @var{name} that runs @var{exp} using
7919 @var{guile}, with @var{exp}'s imported modules in its search path.
7920 Look up @var{exp}'s modules in @var{module-path}.
7922 The example below builds a script that simply invokes the @command{ls}
7926 (use-modules (guix gexp) (gnu packages base))
7928 (gexp->script "list-files"
7929 #~(execl #$(file-append coreutils "/bin/ls")
7933 When ``running'' it through the store (@pxref{The Store Monad,
7934 @code{run-with-store}}), we obtain a derivation that produces an
7935 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7938 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7940 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7944 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7945 [#:guile #f] [#:module-path %load-path]
7946 Return an object representing the executable store item @var{name} that
7947 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7948 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7950 This is the declarative counterpart of @code{gexp->script}.
7953 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7954 [#:set-load-path? #t] [#:module-path %load-path] @
7956 [#:guile (default-guile)]
7957 Return a derivation that builds a file @var{name} containing @var{exp}.
7958 When @var{splice?} is true, @var{exp} is considered to be a list of
7959 expressions that will be spliced in the resulting file.
7961 When @var{set-load-path?} is true, emit code in the resulting file to
7962 set @code{%load-path} and @code{%load-compiled-path} to honor
7963 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7966 The resulting file holds references to all the dependencies of @var{exp}
7967 or a subset thereof.
7970 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
7971 [#:splice? #f] [#:set-load-path? #t]
7972 Return an object representing the Scheme file @var{name} that contains
7975 This is the declarative counterpart of @code{gexp->file}.
7978 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7979 Return as a monadic value a derivation that builds a text file
7980 containing all of @var{text}. @var{text} may list, in addition to
7981 strings, objects of any type that can be used in a gexp: packages,
7982 derivations, local file objects, etc. The resulting store file holds
7983 references to all these.
7985 This variant should be preferred over @code{text-file} anytime the file
7986 to create will reference items from the store. This is typically the
7987 case when building a configuration file that embeds store file names,
7991 (define (profile.sh)
7992 ;; Return the name of a shell script in the store that
7993 ;; initializes the 'PATH' environment variable.
7994 (text-file* "profile.sh"
7995 "export PATH=" coreutils "/bin:"
7996 grep "/bin:" sed "/bin\n"))
7999 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
8000 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
8001 preventing them from being garbage-collected during its lifetime.
8004 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
8005 Return an object representing store file @var{name} containing
8006 @var{text}. @var{text} is a sequence of strings and file-like objects,
8010 (mixed-text-file "profile"
8011 "export PATH=" coreutils "/bin:" grep "/bin")
8014 This is the declarative counterpart of @code{text-file*}.
8017 @deffn {Scheme Procedure} file-union @var{name} @var{files}
8018 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
8019 Each item in @var{files} must be a two-element list where the first element is the
8020 file name to use in the new directory, and the second element is a gexp
8021 denoting the target file. Here's an example:
8025 `(("hosts" ,(plain-file "hosts"
8026 "127.0.0.1 localhost"))
8027 ("bashrc" ,(plain-file "bashrc"
8028 "alias ls='ls --color=auto'"))))
8031 This yields an @code{etc} directory containing these two files.
8034 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
8035 Return a directory that is the union of @var{things}, where @var{things} is a list of
8036 file-like objects denoting directories. For example:
8039 (directory-union "guile+emacs" (list guile emacs))
8042 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
8045 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
8046 Return a file-like object that expands to the concatenation of @var{obj}
8047 and @var{suffix}, where @var{obj} is a lowerable object and each
8048 @var{suffix} is a string.
8050 As an example, consider this gexp:
8053 (gexp->script "run-uname"
8054 #~(system* #$(file-append coreutils
8058 The same effect could be achieved with:
8061 (gexp->script "run-uname"
8062 #~(system* (string-append #$coreutils
8066 There is one difference though: in the @code{file-append} case, the
8067 resulting script contains the absolute file name as a string, whereas in
8068 the second case, the resulting script contains a @code{(string-append
8069 @dots{})} expression to construct the file name @emph{at run time}.
8072 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
8073 This macro is similar to the @code{parameterize} form for
8074 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
8075 Guile Reference Manual}). The key difference is that it takes effect
8076 when the file-like object returned by @var{exp} is lowered to a
8077 derivation or store item.
8079 A typical use of @code{with-parameters} is to force the system in effect
8083 (with-parameters ((%current-system "i686-linux"))
8087 The example above returns an object that corresponds to the i686 build
8088 of Coreutils, regardless of the current value of @code{%current-system}.
8092 Of course, in addition to gexps embedded in ``host'' code, there are
8093 also modules containing build tools. To make it clear that they are
8094 meant to be used in the build stratum, these modules are kept in the
8095 @code{(guix build @dots{})} name space.
8097 @cindex lowering, of high-level objects in gexps
8098 Internally, high-level objects are @dfn{lowered}, using their compiler,
8099 to either derivations or store items. For instance, lowering a package
8100 yields a derivation, and lowering a @code{plain-file} yields a store
8101 item. This is achieved using the @code{lower-object} monadic procedure.
8103 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
8105 Return as a value in @code{%store-monad} the derivation or store item
8106 corresponding to @var{obj} for @var{system}, cross-compiling for
8107 @var{target} if @var{target} is true. @var{obj} must be an object that
8108 has an associated gexp compiler, such as a @code{<package>}.
8111 @node Invoking guix repl
8112 @section Invoking @command{guix repl}
8114 @cindex REPL, read-eval-print loop
8115 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
8116 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
8117 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
8118 command, @command{guix repl} guarantees that all the Guix modules and all its
8119 dependencies are available in the search path. You can use it this way:
8123 scheme@@(guile-user)> ,use (gnu packages base)
8124 scheme@@(guile-user)> coreutils
8125 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
8129 In addition, @command{guix repl} implements a simple machine-readable REPL
8130 protocol for use by @code{(guix inferior)}, a facility to interact with
8131 @dfn{inferiors}, separate processes running a potentially different revision
8134 The available options are as follows:
8137 @item --type=@var{type}
8138 @itemx -t @var{type}
8139 Start a REPL of the given @var{TYPE}, which can be one of the following:
8143 This is default, and it spawns a standard full-featured Guile REPL.
8145 Spawn a REPL that uses the machine-readable protocol. This is the protocol
8146 that the @code{(guix inferior)} module speaks.
8149 @item --listen=@var{endpoint}
8150 By default, @command{guix repl} reads from standard input and writes to
8151 standard output. When this option is passed, it will instead listen for
8152 connections on @var{endpoint}. Here are examples of valid options:
8155 @item --listen=tcp:37146
8156 Accept connections on localhost on port 37146.
8158 @item --listen=unix:/tmp/socket
8159 Accept connections on the Unix-domain socket @file{/tmp/socket}.
8162 @item --load-path=@var{directory}
8163 @itemx -L @var{directory}
8164 Add @var{directory} to the front of the package module search path
8165 (@pxref{Package Modules}).
8167 This allows users to define their own packages and make them visible to
8168 the command-line tool.
8171 Inhibit loading of the @file{~/.guile} file. By default, that
8172 configuration file is loaded when spawning a @code{guile} REPL.
8175 @c *********************************************************************
8179 This section describes Guix command-line utilities. Some of them are
8180 primarily targeted at developers and users who write new package
8181 definitions, while others are more generally useful. They complement
8182 the Scheme programming interface of Guix in a convenient way.
8185 * Invoking guix build:: Building packages from the command line.
8186 * Invoking guix edit:: Editing package definitions.
8187 * Invoking guix download:: Downloading a file and printing its hash.
8188 * Invoking guix hash:: Computing the cryptographic hash of a file.
8189 * Invoking guix import:: Importing package definitions.
8190 * Invoking guix refresh:: Updating package definitions.
8191 * Invoking guix lint:: Finding errors in package definitions.
8192 * Invoking guix size:: Profiling disk usage.
8193 * Invoking guix graph:: Visualizing the graph of packages.
8194 * Invoking guix publish:: Sharing substitutes.
8195 * Invoking guix challenge:: Challenging substitute servers.
8196 * Invoking guix copy:: Copying to and from a remote store.
8197 * Invoking guix container:: Process isolation.
8198 * Invoking guix weather:: Assessing substitute availability.
8199 * Invoking guix processes:: Listing client processes.
8202 @node Invoking guix build
8203 @section Invoking @command{guix build}
8205 @cindex package building
8206 @cindex @command{guix build}
8207 The @command{guix build} command builds packages or derivations and
8208 their dependencies, and prints the resulting store paths. Note that it
8209 does not modify the user's profile---this is the job of the
8210 @command{guix package} command (@pxref{Invoking guix package}). Thus,
8211 it is mainly useful for distribution developers.
8213 The general syntax is:
8216 guix build @var{options} @var{package-or-derivation}@dots{}
8219 As an example, the following command builds the latest versions of Emacs
8220 and of Guile, displays their build logs, and finally displays the
8221 resulting directories:
8224 guix build emacs guile
8227 Similarly, the following command builds all the available packages:
8230 guix build --quiet --keep-going \
8231 `guix package -A | cut -f1,2 --output-delimiter=@@`
8234 @var{package-or-derivation} may be either the name of a package found in
8235 the software distribution such as @code{coreutils} or
8236 @code{coreutils@@8.20}, or a derivation such as
8237 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
8238 package with the corresponding name (and optionally version) is searched
8239 for among the GNU distribution modules (@pxref{Package Modules}).
8241 Alternatively, the @code{--expression} option may be used to specify a
8242 Scheme expression that evaluates to a package; this is useful when
8243 disambiguating among several same-named packages or package variants is
8246 There may be zero or more @var{options}. The available options are
8247 described in the subsections below.
8250 * Common Build Options:: Build options for most commands.
8251 * Package Transformation Options:: Creating variants of packages.
8252 * Additional Build Options:: Options specific to 'guix build'.
8253 * Debugging Build Failures:: Real life packaging experience.
8256 @node Common Build Options
8257 @subsection Common Build Options
8259 A number of options that control the build process are common to
8260 @command{guix build} and other commands that can spawn builds, such as
8261 @command{guix package} or @command{guix archive}. These are the
8266 @item --load-path=@var{directory}
8267 @itemx -L @var{directory}
8268 Add @var{directory} to the front of the package module search path
8269 (@pxref{Package Modules}).
8271 This allows users to define their own packages and make them visible to
8272 the command-line tools.
8276 Keep the build tree of failed builds. Thus, if a build fails, its build
8277 tree is kept under @file{/tmp}, in a directory whose name is shown at
8278 the end of the build log. This is useful when debugging build issues.
8279 @xref{Debugging Build Failures}, for tips and tricks on how to debug
8282 This option implies @option{--no-offload}, and it has no effect when
8283 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
8284 Store, the @code{GUIX_DAEMON_SOCKET} variable}).
8288 Keep going when some of the derivations fail to build; return only once
8289 all the builds have either completed or failed.
8291 The default behavior is to stop as soon as one of the specified
8292 derivations has failed.
8296 Do not build the derivations.
8298 @anchor{fallback-option}
8300 When substituting a pre-built binary fails, fall back to building
8301 packages locally (@pxref{Substitution Failure}).
8303 @item --substitute-urls=@var{urls}
8304 @anchor{client-substitute-urls}
8305 Consider @var{urls} the whitespace-separated list of substitute source
8306 URLs, overriding the default list of URLs of @command{guix-daemon}
8307 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
8309 This means that substitutes may be downloaded from @var{urls}, provided
8310 they are signed by a key authorized by the system administrator
8311 (@pxref{Substitutes}).
8313 When @var{urls} is the empty string, substitutes are effectively
8316 @item --no-substitutes
8317 Do not use substitutes for build products. That is, always build things
8318 locally instead of allowing downloads of pre-built binaries
8319 (@pxref{Substitutes}).
8322 Do not ``graft'' packages. In practice, this means that package updates
8323 available as grafts are not applied. @xref{Security Updates}, for more
8324 information on grafts.
8326 @item --rounds=@var{n}
8327 Build each derivation @var{n} times in a row, and raise an error if
8328 consecutive build results are not bit-for-bit identical.
8330 This is a useful way to detect non-deterministic builds processes.
8331 Non-deterministic build processes are a problem because they make it
8332 practically impossible for users to @emph{verify} whether third-party
8333 binaries are genuine. @xref{Invoking guix challenge}, for more.
8335 Note that, currently, the differing build results are not kept around,
8336 so you will have to manually investigate in case of an error---e.g., by
8337 stashing one of the build results with @code{guix archive --export}
8338 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8342 Do not use offload builds to other machines (@pxref{Daemon Offload
8343 Setup}). That is, always build things locally instead of offloading
8344 builds to remote machines.
8346 @item --max-silent-time=@var{seconds}
8347 When the build or substitution process remains silent for more than
8348 @var{seconds}, terminate it and report a build failure.
8350 By default, the daemon's setting is honored (@pxref{Invoking
8351 guix-daemon, @code{--max-silent-time}}).
8353 @item --timeout=@var{seconds}
8354 Likewise, when the build or substitution process lasts for more than
8355 @var{seconds}, terminate it and report a build failure.
8357 By default, the daemon's setting is honored (@pxref{Invoking
8358 guix-daemon, @code{--timeout}}).
8360 @c Note: This option is actually not part of %standard-build-options but
8361 @c most programs honor it.
8362 @cindex verbosity, of the command-line tools
8363 @cindex build logs, verbosity
8364 @item -v @var{level}
8365 @itemx --verbosity=@var{level}
8366 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8367 output is produced, 1 is for quiet output, and 2 shows all the build log
8368 output on standard error.
8370 @item --cores=@var{n}
8372 Allow the use of up to @var{n} CPU cores for the build. The special
8373 value @code{0} means to use as many CPU cores as available.
8375 @item --max-jobs=@var{n}
8377 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8378 guix-daemon, @code{--max-jobs}}, for details about this option and the
8379 equivalent @command{guix-daemon} option.
8381 @item --debug=@var{level}
8382 Produce debugging output coming from the build daemon. @var{level} must be an
8383 integer between 0 and 5; higher means more verbose output. Setting a level of
8384 4 or more may be helpful when debugging setup issues with the build daemon.
8388 Behind the scenes, @command{guix build} is essentially an interface to
8389 the @code{package-derivation} procedure of the @code{(guix packages)}
8390 module, and to the @code{build-derivations} procedure of the @code{(guix
8391 derivations)} module.
8393 In addition to options explicitly passed on the command line,
8394 @command{guix build} and other @command{guix} commands that support
8395 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
8397 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8398 Users can define this variable to a list of command line options that
8399 will automatically be used by @command{guix build} and other
8400 @command{guix} commands that can perform builds, as in the example
8404 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8407 These options are parsed independently, and the result is appended to
8408 the parsed command-line options.
8412 @node Package Transformation Options
8413 @subsection Package Transformation Options
8415 @cindex package variants
8416 Another set of command-line options supported by @command{guix build}
8417 and also @command{guix package} are @dfn{package transformation
8418 options}. These are options that make it possible to define @dfn{package
8419 variants}---for instance, packages built from different source code.
8420 This is a convenient way to create customized packages on the fly
8421 without having to type in the definitions of package variants
8422 (@pxref{Defining Packages}).
8426 @item --with-source=@var{source}
8427 @itemx --with-source=@var{package}=@var{source}
8428 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8429 Use @var{source} as the source of @var{package}, and @var{version} as
8431 @var{source} must be a file name or a URL, as for @command{guix
8432 download} (@pxref{Invoking guix download}).
8434 When @var{package} is omitted,
8435 it is taken to be the package name specified on the
8436 command line that matches the base of @var{source}---e.g.,
8437 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8438 package is @code{guile}.
8440 Likewise, when @var{version} is omitted, the version string is inferred from
8441 @var{source}; in the previous example, it is @code{2.0.10}.
8443 This option allows users to try out versions of packages other than the
8444 one provided by the distribution. The example below downloads
8445 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8446 the @code{ed} package:
8449 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8452 As a developer, @code{--with-source} makes it easy to test release
8456 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8459 @dots{} or to build from a checkout in a pristine environment:
8462 $ git clone git://git.sv.gnu.org/guix.git
8463 $ guix build guix --with-source=guix@@1.0=./guix
8466 @item --with-input=@var{package}=@var{replacement}
8467 Replace dependency on @var{package} by a dependency on
8468 @var{replacement}. @var{package} must be a package name, and
8469 @var{replacement} must be a package specification such as @code{guile}
8470 or @code{guile@@1.8}.
8472 For instance, the following command builds Guix, but replaces its
8473 dependency on the current stable version of Guile with a dependency on
8474 the legacy version of Guile, @code{guile@@2.0}:
8477 guix build --with-input=guile=guile@@2.0 guix
8480 This is a recursive, deep replacement. So in this example, both
8481 @code{guix} and its dependency @code{guile-json} (which also depends on
8482 @code{guile}) get rebuilt against @code{guile@@2.0}.
8484 This is implemented using the @code{package-input-rewriting} Scheme
8485 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8487 @item --with-graft=@var{package}=@var{replacement}
8488 This is similar to @code{--with-input} but with an important difference:
8489 instead of rebuilding the whole dependency chain, @var{replacement} is
8490 built and then @dfn{grafted} onto the binaries that were initially
8491 referring to @var{package}. @xref{Security Updates}, for more
8492 information on grafts.
8494 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8495 and all its dependencies, replacing references to the version of GnuTLS
8496 they currently refer to:
8499 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8502 This has the advantage of being much faster than rebuilding everything.
8503 But there is a caveat: it works if and only if @var{package} and
8504 @var{replacement} are strictly compatible---for example, if they provide
8505 a library, the application binary interface (ABI) of those libraries
8506 must be compatible. If @var{replacement} is somehow incompatible with
8507 @var{package}, then the resulting package may be unusable. Use with
8510 @item --with-git-url=@var{package}=@var{url}
8511 @cindex Git, using the latest commit
8512 @cindex latest commit, building
8513 Build @var{package} from the latest commit of the @code{master} branch of the
8514 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8517 For example, the following command builds the NumPy Python library against the
8518 latest commit of the master branch of Python itself:
8521 guix build python-numpy \
8522 --with-git-url=python=https://github.com/python/cpython
8525 This option can also be combined with @code{--with-branch} or
8526 @code{--with-commit} (see below).
8528 @cindex continuous integration
8529 Obviously, since it uses the latest commit of the given branch, the result of
8530 such a command varies over time. Nevertheless it is a convenient way to
8531 rebuild entire software stacks against the latest commit of one or more
8532 packages. This is particularly useful in the context of continuous
8535 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8536 consecutive accesses to the same repository. You may want to clean it up once
8537 in a while to save disk space.
8539 @item --with-branch=@var{package}=@var{branch}
8540 Build @var{package} from the latest commit of @var{branch}. If the
8541 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8542 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8543 repository URL is taken from that @code{source}. Otherwise you have to use
8544 @code{--with-git-url} to specify the URL of the Git repository.
8546 For instance, the following command builds @code{guile-sqlite3} from the
8547 latest commit of its @code{master} branch, and then builds @code{guix} (which
8548 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8549 specific @code{guile-sqlite3} build:
8552 guix build --with-branch=guile-sqlite3=master cuirass
8555 @item --with-commit=@var{package}=@var{commit}
8556 This is similar to @code{--with-branch}, except that it builds from
8557 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8558 Git commit SHA1 identifier or a tag.
8561 @node Additional Build Options
8562 @subsection Additional Build Options
8564 The command-line options presented below are specific to @command{guix
8571 Build quietly, without displaying the build log; this is equivalent to
8572 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8573 (or similar) and can always be retrieved using the @option{--log-file} option.
8575 @item --file=@var{file}
8576 @itemx -f @var{file}
8577 Build the package, derivation, or other file-like object that the code within
8578 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8580 As an example, @var{file} might contain a package definition like this
8581 (@pxref{Defining Packages}):
8584 @include package-hello.scm
8587 The @var{file} may also contain a JSON representation of one or more
8588 package definitions. Running @code{guix build -f} on @file{hello.json}
8589 with the following contents would result in building the packages
8590 @code{myhello} and @code{greeter}:
8593 @verbatiminclude package-hello.json
8596 @item --manifest=@var{manifest}
8597 @itemx -m @var{manifest}
8598 Build all packages listed in the given @var{manifest}
8599 (@pxref{profile-manifest, @option{--manifest}}).
8601 @item --expression=@var{expr}
8602 @itemx -e @var{expr}
8603 Build the package or derivation @var{expr} evaluates to.
8605 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8606 guile-1.8)}, which unambiguously designates this specific variant of
8607 version 1.8 of Guile.
8609 Alternatively, @var{expr} may be a G-expression, in which case it is used
8610 as a build program passed to @code{gexp->derivation}
8611 (@pxref{G-Expressions}).
8613 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8614 (@pxref{The Store Monad}). The procedure must return a derivation as a
8615 monadic value, which is then passed through @code{run-with-store}.
8619 Build the source derivations of the packages, rather than the packages
8622 For instance, @code{guix build -S gcc} returns something like
8623 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8626 The returned source tarball is the result of applying any patches and
8627 code snippets specified in the package @code{origin} (@pxref{Defining
8630 Note that @command{guix build -S} compiles the sources only of the
8631 specified packages. They do not include the sources of statically
8632 linked dependencies and by themselves are insufficient for reproducing
8636 Fetch and return the source of @var{package-or-derivation} and all their
8637 dependencies, recursively. This is a handy way to obtain a local copy
8638 of all the source code needed to build @var{packages}, allowing you to
8639 eventually build them even without network access. It is an extension
8640 of the @code{--source} option and can accept one of the following
8641 optional argument values:
8645 This value causes the @code{--sources} option to behave in the same way
8646 as the @code{--source} option.
8649 Build the source derivations of all packages, including any source that
8650 might be listed as @code{inputs}. This is the default value.
8653 $ guix build --sources tzdata
8654 The following derivations will be built:
8655 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8656 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8660 Build the source derivations of all packages, as well of all transitive
8661 inputs to the packages. This can be used e.g.@: to
8662 prefetch package source for later offline building.
8665 $ guix build --sources=transitive tzdata
8666 The following derivations will be built:
8667 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8668 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8669 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8670 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8671 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8672 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8678 @item --system=@var{system}
8679 @itemx -s @var{system}
8680 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8681 the system type of the build host. The @command{guix build} command allows
8682 you to repeat this option several times, in which case it builds for all the
8683 specified systems; other commands ignore extraneous @option{-s} options.
8686 The @code{--system} flag is for @emph{native} compilation and must not
8687 be confused with cross-compilation. See @code{--target} below for
8688 information on cross-compilation.
8691 An example use of this is on Linux-based systems, which can emulate
8692 different personalities. For instance, passing
8693 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8694 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8695 to build packages in a complete 32-bit environment.
8698 Building for an @code{armhf-linux} system is unconditionally enabled on
8699 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8700 allow for this functionality, notably the ThunderX.
8703 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8704 is enabled (@pxref{Virtualization Services,
8705 @code{qemu-binfmt-service-type}}), you can build for any system for
8706 which a QEMU @code{binfmt_misc} handler is installed.
8708 Builds for a system other than that of the machine you are using can
8709 also be offloaded to a remote machine of the right architecture.
8710 @xref{Daemon Offload Setup}, for more information on offloading.
8712 @item --target=@var{triplet}
8713 @cindex cross-compilation
8714 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8715 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8716 configuration triplets,, autoconf, Autoconf}).
8718 @anchor{build-check}
8720 @cindex determinism, checking
8721 @cindex reproducibility, checking
8722 Rebuild @var{package-or-derivation}, which are already available in the
8723 store, and raise an error if the build results are not bit-for-bit
8726 This mechanism allows you to check whether previously installed
8727 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8728 of a package is deterministic. @xref{Invoking guix challenge}, for more
8729 background information and tools.
8731 When used in conjunction with @option{--keep-failed}, the differing
8732 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8733 This makes it easy to look for differences between the two results.
8736 @cindex repairing store items
8737 @cindex corruption, recovering from
8738 Attempt to repair the specified store items, if they are corrupt, by
8739 re-downloading or rebuilding them.
8741 This operation is not atomic and thus restricted to @code{root}.
8745 Return the derivation paths, not the output paths, of the given
8748 @item --root=@var{file}
8749 @itemx -r @var{file}
8750 @cindex GC roots, adding
8751 @cindex garbage collector roots, adding
8752 Make @var{file} a symlink to the result, and register it as a garbage
8755 Consequently, the results of this @command{guix build} invocation are
8756 protected from garbage collection until @var{file} is removed. When
8757 that option is omitted, build results are eligible for garbage
8758 collection as soon as the build completes. @xref{Invoking guix gc}, for
8762 @cindex build logs, access
8763 Return the build log file names or URLs for the given
8764 @var{package-or-derivation}, or raise an error if build logs are
8767 This works regardless of how packages or derivations are specified. For
8768 instance, the following invocations are equivalent:
8771 guix build --log-file `guix build -d guile`
8772 guix build --log-file `guix build guile`
8773 guix build --log-file guile
8774 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8777 If a log is unavailable locally, and unless @code{--no-substitutes} is
8778 passed, the command looks for a corresponding log on one of the
8779 substitute servers (as specified with @code{--substitute-urls}.)
8781 So for instance, imagine you want to see the build log of GDB on MIPS,
8782 but you are actually on an @code{x86_64} machine:
8785 $ guix build --log-file gdb -s mips64el-linux
8786 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8789 You can freely access a huge library of build logs!
8792 @node Debugging Build Failures
8793 @subsection Debugging Build Failures
8795 @cindex build failures, debugging
8796 When defining a new package (@pxref{Defining Packages}), you will
8797 probably find yourself spending some time debugging and tweaking the
8798 build until it succeeds. To do that, you need to operate the build
8799 commands yourself in an environment as close as possible to the one the
8802 To that end, the first thing to do is to use the @option{--keep-failed}
8803 or @option{-K} option of @command{guix build}, which will keep the
8804 failed build tree in @file{/tmp} or whatever directory you specified as
8805 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8807 From there on, you can @command{cd} to the failed build tree and source
8808 the @file{environment-variables} file, which contains all the
8809 environment variable definitions that were in place when the build
8810 failed. So let's say you're debugging a build failure in package
8811 @code{foo}; a typical session would look like this:
8815 @dots{} @i{build fails}
8816 $ cd /tmp/guix-build-foo.drv-0
8817 $ source ./environment-variables
8821 Now, you can invoke commands as if you were the daemon (almost) and
8822 troubleshoot your build process.
8824 Sometimes it happens that, for example, a package's tests pass when you
8825 run them manually but they fail when the daemon runs them. This can
8826 happen because the daemon runs builds in containers where, unlike in our
8827 environment above, network access is missing, @file{/bin/sh} does not
8828 exist, etc. (@pxref{Build Environment Setup}).
8830 In such cases, you may need to run inspect the build process from within
8831 a container similar to the one the build daemon creates:
8836 $ cd /tmp/guix-build-foo.drv-0
8837 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8838 [env]# source ./environment-variables
8842 Here, @command{guix environment -C} creates a container and spawns a new
8843 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8844 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8845 the container, which you may find handy while debugging. The
8846 @option{--no-grafts} option makes sure we get the exact same
8847 environment, with ungrafted packages (@pxref{Security Updates}, for more
8850 To get closer to a container like that used by the build daemon, we can
8851 remove @file{/bin/sh}:
8857 (Don't worry, this is harmless: this is all happening in the throw-away
8858 container created by @command{guix environment}.)
8860 The @command{strace} command is probably not in the search path, but we
8864 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8867 In this way, not only you will have reproduced the environment variables
8868 the daemon uses, you will also be running the build process in a container
8869 similar to the one the daemon uses.
8872 @node Invoking guix edit
8873 @section Invoking @command{guix edit}
8875 @cindex @command{guix edit}
8876 @cindex package definition, editing
8877 So many packages, so many source files! The @command{guix edit} command
8878 facilitates the life of users and packagers by pointing their editor at
8879 the source file containing the definition of the specified packages.
8883 guix edit gcc@@4.9 vim
8887 launches the program specified in the @code{VISUAL} or in the
8888 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8891 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8892 have created your own packages on @code{GUIX_PACKAGE_PATH}
8893 (@pxref{Package Modules}), you will be able to edit the package
8894 recipes. In other cases, you will be able to examine the read-only recipes
8895 for packages currently in the store.
8897 Instead of @code{GUIX_PACKAGE_PATH}, the command-line option
8898 @code{--load-path=@var{directory}} (or in short @code{-L
8899 @var{directory}}) allows you to add @var{directory} to the front of the
8900 package module search path and so make your own packages visible.
8902 @node Invoking guix download
8903 @section Invoking @command{guix download}
8905 @cindex @command{guix download}
8906 @cindex downloading package sources
8907 When writing a package definition, developers typically need to download
8908 a source tarball, compute its SHA256 hash, and write that
8909 hash in the package definition (@pxref{Defining Packages}). The
8910 @command{guix download} tool helps with this task: it downloads a file
8911 from the given URI, adds it to the store, and prints both its file name
8912 in the store and its SHA256 hash.
8914 The fact that the downloaded file is added to the store saves bandwidth:
8915 when the developer eventually tries to build the newly defined package
8916 with @command{guix build}, the source tarball will not have to be
8917 downloaded again because it is already in the store. It is also a
8918 convenient way to temporarily stash files, which may be deleted
8919 eventually (@pxref{Invoking guix gc}).
8921 The @command{guix download} command supports the same URIs as used in
8922 package definitions. In particular, it supports @code{mirror://} URIs.
8923 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8924 Guile bindings for GnuTLS are available in the user's environment; when
8925 they are not available, an error is raised. @xref{Guile Preparations,
8926 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8927 GnuTLS-Guile}, for more information.
8929 @command{guix download} verifies HTTPS server certificates by loading
8930 the certificates of X.509 authorities from the directory pointed to by
8931 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8932 Certificates}), unless @option{--no-check-certificate} is used.
8934 The following options are available:
8937 @item --format=@var{fmt}
8939 Write the hash in the format specified by @var{fmt}. For more
8940 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8942 @item --no-check-certificate
8943 Do not validate the X.509 certificates of HTTPS servers.
8945 When using this option, you have @emph{absolutely no guarantee} that you
8946 are communicating with the authentic server responsible for the given
8947 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8949 @item --output=@var{file}
8950 @itemx -o @var{file}
8951 Save the downloaded file to @var{file} instead of adding it to the
8955 @node Invoking guix hash
8956 @section Invoking @command{guix hash}
8958 @cindex @command{guix hash}
8959 The @command{guix hash} command computes the SHA256 hash of a file.
8960 It is primarily a convenience tool for anyone contributing to the
8961 distribution: it computes the cryptographic hash of a file, which can be
8962 used in the definition of a package (@pxref{Defining Packages}).
8964 The general syntax is:
8967 guix hash @var{option} @var{file}
8970 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8971 hash of data read from standard input. @command{guix hash} has the
8976 @item --format=@var{fmt}
8978 Write the hash in the format specified by @var{fmt}.
8980 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8981 (@code{hex} and @code{hexadecimal} can be used as well).
8983 If the @option{--format} option is not specified, @command{guix hash}
8984 will output the hash in @code{nix-base32}. This representation is used
8985 in the definitions of packages.
8989 Compute the hash on @var{file} recursively.
8991 In this case, the hash is computed on an archive containing @var{file},
8992 including its children if it is a directory. Some of the metadata of
8993 @var{file} is part of the archive; for instance, when @var{file} is a
8994 regular file, the hash is different depending on whether @var{file} is
8995 executable or not. Metadata such as time stamps has no impact on the
8996 hash (@pxref{Invoking guix archive}).
8997 @c FIXME: Replace xref above with xref to an ``Archive'' section when
9002 When combined with @option{--recursive}, exclude version control system
9003 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
9006 As an example, here is how you would compute the hash of a Git checkout,
9007 which is useful when using the @code{git-fetch} method (@pxref{origin
9011 $ git clone http://example.org/foo.git
9017 @node Invoking guix import
9018 @section Invoking @command{guix import}
9020 @cindex importing packages
9021 @cindex package import
9022 @cindex package conversion
9023 @cindex Invoking @command{guix import}
9024 The @command{guix import} command is useful for people who would like to
9025 add a package to the distribution with as little work as
9026 possible---a legitimate demand. The command knows of a few
9027 repositories from which it can ``import'' package metadata. The result
9028 is a package definition, or a template thereof, in the format we know
9029 (@pxref{Defining Packages}).
9031 The general syntax is:
9034 guix import @var{importer} @var{options}@dots{}
9037 @var{importer} specifies the source from which to import package
9038 metadata, and @var{options} specifies a package identifier and other
9039 options specific to @var{importer}.
9041 Some of the importers rely on the ability to run the @command{gpgv} command.
9042 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
9045 Currently, the available ``importers'' are:
9049 Import metadata for the given GNU package. This provides a template
9050 for the latest version of that GNU package, including the hash of its
9051 source tarball, and its canonical synopsis and description.
9053 Additional information such as the package dependencies and its
9054 license needs to be figured out manually.
9056 For example, the following command returns a package definition for
9060 guix import gnu hello
9063 Specific command-line options are:
9066 @item --key-download=@var{policy}
9067 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
9068 keys when verifying the package signature. @xref{Invoking guix
9069 refresh, @code{--key-download}}.
9074 Import metadata from the @uref{https://pypi.python.org/, Python Package
9075 Index}. Information is taken from the JSON-formatted description
9076 available at @code{pypi.python.org} and usually includes all the relevant
9077 information, including package dependencies. For maximum efficiency, it
9078 is recommended to install the @command{unzip} utility, so that the
9079 importer can unzip Python wheels and gather data from them.
9081 The command below imports metadata for the @code{itsdangerous} Python
9085 guix import pypi itsdangerous
9091 Traverse the dependency graph of the given upstream package recursively
9092 and generate package expressions for all those packages that are not yet
9098 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
9099 is taken from the JSON-formatted description available at
9100 @code{rubygems.org} and includes most relevant information, including
9101 runtime dependencies. There are some caveats, however. The metadata
9102 doesn't distinguish between synopses and descriptions, so the same string
9103 is used for both fields. Additionally, the details of non-Ruby
9104 dependencies required to build native extensions is unavailable and left
9105 as an exercise to the packager.
9107 The command below imports metadata for the @code{rails} Ruby package:
9110 guix import gem rails
9116 Traverse the dependency graph of the given upstream package recursively
9117 and generate package expressions for all those packages that are not yet
9123 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
9124 Information is taken from the JSON-formatted metadata provided through
9125 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
9126 relevant information, such as module dependencies. License information
9127 should be checked closely. If Perl is available in the store, then the
9128 @code{corelist} utility will be used to filter core modules out of the
9129 list of dependencies.
9131 The command command below imports metadata for the @code{Acme::Boolean}
9135 guix import cpan Acme::Boolean
9140 @cindex Bioconductor
9141 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
9142 central repository for the @uref{https://r-project.org, GNU@tie{}R
9143 statistical and graphical environment}.
9145 Information is extracted from the @code{DESCRIPTION} file of the package.
9147 The command command below imports metadata for the @code{Cairo}
9151 guix import cran Cairo
9154 When @code{--recursive} is added, the importer will traverse the
9155 dependency graph of the given upstream package recursively and generate
9156 package expressions for all those packages that are not yet in Guix.
9158 When @code{--archive=bioconductor} is added, metadata is imported from
9159 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
9160 packages for for the analysis and comprehension of high-throughput
9161 genomic data in bioinformatics.
9163 Information is extracted from the @code{DESCRIPTION} file contained in the
9166 The command below imports metadata for the @code{GenomicRanges}
9170 guix import cran --archive=bioconductor GenomicRanges
9173 Finally, you can also import R packages that have not yet been published on
9174 CRAN or Bioconductor as long as they are in a git repository. Use
9175 @code{--archive=git} followed by the URL of the git repository:
9178 guix import cran --archive=git https://github.com/immunogenomics/harmony
9184 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
9185 comprehensive TeX archive network for TeX packages that are part of the
9186 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
9188 Information about the package is obtained through the XML API provided
9189 by CTAN, while the source code is downloaded from the SVN repository of
9190 the Tex Live project. This is done because the CTAN does not keep
9193 The command command below imports metadata for the @code{fontspec}
9197 guix import texlive fontspec
9200 When @code{--archive=DIRECTORY} is added, the source code is downloaded
9201 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
9202 tree in the TeX Live SVN repository, but from the specified sibling
9203 directory under the same root.
9205 The command below imports metadata for the @code{ifxetex} package from
9206 CTAN while fetching the sources from the directory
9207 @file{texmf/source/generic}:
9210 guix import texlive --archive=generic ifxetex
9214 @cindex JSON, import
9215 Import package metadata from a local JSON file. Consider the following
9216 example package definition in JSON format:
9222 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
9223 "build-system": "gnu",
9224 "home-page": "https://www.gnu.org/software/hello/",
9225 "synopsis": "Hello, GNU world: An example GNU package",
9226 "description": "GNU Hello prints a greeting.",
9227 "license": "GPL-3.0+",
9228 "native-inputs": ["gettext"]
9232 The field names are the same as for the @code{<package>} record
9233 (@xref{Defining Packages}). References to other packages are provided
9234 as JSON lists of quoted package specification strings such as
9235 @code{guile} or @code{guile@@2.0}.
9237 The importer also supports a more explicit source definition using the
9238 common fields for @code{<origin>} records:
9244 "method": "url-fetch",
9245 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
9247 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
9254 The command below reads metadata from the JSON file @code{hello.json}
9255 and outputs a package expression:
9258 guix import json hello.json
9262 Import metadata from a local copy of the source of the
9263 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
9264 relies on the @command{nix-instantiate} command of
9265 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
9266 typically written in a mixture of Nix-language and Bash code. This
9267 command only imports the high-level package structure that is written in
9268 the Nix language. It normally includes all the basic fields of a
9271 When importing a GNU package, the synopsis and descriptions are replaced
9272 by their canonical upstream variant.
9274 Usually, you will first need to do:
9277 export NIX_REMOTE=daemon
9281 so that @command{nix-instantiate} does not try to open the Nix database.
9283 As an example, the command below imports the package definition of
9284 LibreOffice (more precisely, it imports the definition of the package
9285 bound to the @code{libreoffice} top-level attribute):
9288 guix import nix ~/path/to/nixpkgs libreoffice
9293 Import metadata from the Haskell community's central package archive
9294 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
9295 Cabal files and includes all the relevant information, including package
9298 Specific command-line options are:
9303 Read a Cabal file from standard input.
9304 @item --no-test-dependencies
9306 Do not include dependencies required only by the test suites.
9307 @item --cabal-environment=@var{alist}
9308 @itemx -e @var{alist}
9309 @var{alist} is a Scheme alist defining the environment in which the
9310 Cabal conditionals are evaluated. The accepted keys are: @code{os},
9311 @code{arch}, @code{impl} and a string representing the name of a flag.
9312 The value associated with a flag has to be either the symbol
9313 @code{true} or @code{false}. The value associated with other keys
9314 has to conform to the Cabal file format definition. The default value
9315 associated with the keys @code{os}, @code{arch} and @code{impl} is
9316 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
9319 Traverse the dependency graph of the given upstream package recursively
9320 and generate package expressions for all those packages that are not yet
9324 The command below imports metadata for the latest version of the
9325 @code{HTTP} Haskell package without including test dependencies and
9326 specifying the value of the flag @samp{network-uri} as @code{false}:
9329 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
9332 A specific package version may optionally be specified by following the
9333 package name by an at-sign and a version number as in the following example:
9336 guix import hackage mtl@@2.1.3.1
9341 The @code{stackage} importer is a wrapper around the @code{hackage} one.
9342 It takes a package name, looks up the package version included in a
9343 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
9344 release and uses the @code{hackage} importer to retrieve its metadata.
9345 Note that it is up to you to select an LTS release compatible with the
9346 GHC compiler used by Guix.
9348 Specific command-line options are:
9351 @item --no-test-dependencies
9353 Do not include dependencies required only by the test suites.
9354 @item --lts-version=@var{version}
9355 @itemx -l @var{version}
9356 @var{version} is the desired LTS release version. If omitted the latest
9360 Traverse the dependency graph of the given upstream package recursively
9361 and generate package expressions for all those packages that are not yet
9365 The command below imports metadata for the @code{HTTP} Haskell package
9366 included in the LTS Stackage release version 7.18:
9369 guix import stackage --lts-version=7.18 HTTP
9374 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9375 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9377 Specific command-line options are:
9380 @item --archive=@var{repo}
9381 @itemx -a @var{repo}
9382 @var{repo} identifies the archive repository from which to retrieve the
9383 information. Currently the supported repositories and their identifiers
9387 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9388 identifier. This is the default.
9390 Packages from @code{elpa.gnu.org} are signed with one of the keys
9391 contained in the GnuPG keyring at
9392 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9393 @code{emacs} package (@pxref{Package Installation, ELPA package
9394 signatures,, emacs, The GNU Emacs Manual}).
9397 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9398 @code{melpa-stable} identifier.
9401 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9407 Traverse the dependency graph of the given upstream package recursively
9408 and generate package expressions for all those packages that are not yet
9414 Import metadata from the crates.io Rust package repository
9415 @uref{https://crates.io, crates.io}, as in this example:
9418 guix import crate blake2-rfc
9421 The crate importer also allows you to specify a version string:
9424 guix import crate constant-time-eq@@0.1.0
9427 Additional options include:
9432 Traverse the dependency graph of the given upstream package recursively
9433 and generate package expressions for all those packages that are not yet
9440 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9441 repository used by the OCaml community.
9444 The structure of the @command{guix import} code is modular. It would be
9445 useful to have more importers for other package formats, and your help
9446 is welcome here (@pxref{Contributing}).
9448 @node Invoking guix refresh
9449 @section Invoking @command{guix refresh}
9451 @cindex @command {guix refresh}
9452 The primary audience of the @command{guix refresh} command is developers
9453 of the GNU software distribution. By default, it reports any packages
9454 provided by the distribution that are outdated compared to the latest
9455 upstream version, like this:
9459 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9460 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9463 Alternately, one can specify packages to consider, in which case a
9464 warning is emitted for packages that lack an updater:
9467 $ guix refresh coreutils guile guile-ssh
9468 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9469 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9472 @command{guix refresh} browses the upstream repository of each package and determines
9473 the highest version number of the releases therein. The command
9474 knows how to update specific types of packages: GNU packages, ELPA
9475 packages, etc.---see the documentation for @option{--type} below. There
9476 are many packages, though, for which it lacks a method to determine
9477 whether a new upstream release is available. However, the mechanism is
9478 extensible, so feel free to get in touch with us to add a new method!
9483 Consider the packages specified, and all the packages upon which they depend.
9486 $ guix refresh --recursive coreutils
9487 gnu/packages/acl.scm:35:2: warning: no updater for acl
9488 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9489 gnu/packages/xml.scm:68:2: warning: no updater for expat
9490 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9496 Sometimes the upstream name differs from the package name used in Guix,
9497 and @command{guix refresh} needs a little help. Most updaters honor the
9498 @code{upstream-name} property in package definitions, which can be used
9502 (define-public network-manager
9504 (name "network-manager")
9506 (properties '((upstream-name . "NetworkManager")))))
9509 When passed @code{--update}, it modifies distribution source files to
9510 update the version numbers and source tarball hashes of those package
9511 recipes (@pxref{Defining Packages}). This is achieved by downloading
9512 each package's latest source tarball and its associated OpenPGP
9513 signature, authenticating the downloaded tarball against its signature
9514 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
9515 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
9518 key used to sign the tarball is missing from the user's keyring, an
9519 attempt is made to automatically retrieve it from a public key server;
9520 when this is successful, the key is added to the user's keyring; otherwise,
9521 @command{guix refresh} reports an error.
9523 The following options are supported:
9527 @item --expression=@var{expr}
9528 @itemx -e @var{expr}
9529 Consider the package @var{expr} evaluates to.
9531 This is useful to precisely refer to a package, as in this example:
9534 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9537 This command lists the dependents of the ``final'' libc (essentially all
9542 Update distribution source files (package recipes) in place. This is
9543 usually run from a checkout of the Guix source tree (@pxref{Running
9544 Guix Before It Is Installed}):
9547 $ ./pre-inst-env guix refresh -s non-core -u
9550 @xref{Defining Packages}, for more information on package definitions.
9552 @item --select=[@var{subset}]
9553 @itemx -s @var{subset}
9554 Select all the packages in @var{subset}, one of @code{core} or
9557 The @code{core} subset refers to all the packages at the core of the
9558 distribution---i.e., packages that are used to build ``everything
9559 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9560 changing one of these packages in the distribution entails a rebuild of
9561 all the others. Thus, such updates are an inconvenience to users in
9562 terms of build time or bandwidth used to achieve the upgrade.
9564 The @code{non-core} subset refers to the remaining packages. It is
9565 typically useful in cases where an update of the core packages would be
9568 @item --manifest=@var{file}
9569 @itemx -m @var{file}
9570 Select all the packages from the manifest in @var{file}. This is useful to
9571 check if any packages of the user manifest can be updated.
9573 @item --type=@var{updater}
9574 @itemx -t @var{updater}
9575 Select only packages handled by @var{updater} (may be a comma-separated
9576 list of updaters). Currently, @var{updater} may be one of:
9580 the updater for GNU packages;
9582 the updater for GNOME packages;
9584 the updater for KDE packages;
9586 the updater for X.org packages;
9588 the updater for packages hosted on kernel.org;
9590 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9592 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9594 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9596 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9598 the updater for @uref{https://pypi.python.org, PyPI} packages.
9600 the updater for @uref{https://rubygems.org, RubyGems} packages.
9602 the updater for @uref{https://github.com, GitHub} packages.
9604 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9606 the updater for @uref{https://www.stackage.org, Stackage} packages.
9608 the updater for @uref{https://crates.io, Crates} packages.
9610 the updater for @uref{https://launchpad.net, Launchpad} packages.
9613 For instance, the following command only checks for updates of Emacs
9614 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9617 $ guix refresh --type=elpa,cran
9618 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9619 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9624 In addition, @command{guix refresh} can be passed one or more package
9625 names, as in this example:
9628 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9632 The command above specifically updates the @code{emacs} and
9633 @code{idutils} packages. The @code{--select} option would have no
9634 effect in this case.
9636 When considering whether to upgrade a package, it is sometimes
9637 convenient to know which packages would be affected by the upgrade and
9638 should be checked for compatibility. For this the following option may
9639 be used when passing @command{guix refresh} one or more package names:
9643 @item --list-updaters
9645 List available updaters and exit (see @option{--type} above.)
9647 For each updater, display the fraction of packages it covers; at the
9648 end, display the fraction of packages covered by all these updaters.
9650 @item --list-dependent
9652 List top-level dependent packages that would need to be rebuilt as a
9653 result of upgrading one or more packages.
9655 @xref{Invoking guix graph, the @code{reverse-package} type of
9656 @command{guix graph}}, for information on how to visualize the list of
9657 dependents of a package.
9661 Be aware that the @code{--list-dependent} option only
9662 @emph{approximates} the rebuilds that would be required as a result of
9663 an upgrade. More rebuilds might be required under some circumstances.
9666 $ guix refresh --list-dependent flex
9667 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9668 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9671 The command above lists a set of packages that could be built to check
9672 for compatibility with an upgraded @code{flex} package.
9676 @item --list-transitive
9677 List all the packages which one or more packages depend upon.
9680 $ guix refresh --list-transitive flex
9681 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9682 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{}
9687 The command above lists a set of packages which, when changed, would cause
9688 @code{flex} to be rebuilt.
9690 The following options can be used to customize GnuPG operation:
9694 @item --gpg=@var{command}
9695 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9696 for in @code{$PATH}.
9698 @item --keyring=@var{file}
9699 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9700 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9701 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9702 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9703 information on a tool to manipulate keybox files).
9705 When this option is omitted, @command{guix refresh} uses
9706 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9707 signing keys. OpenPGP signatures are checked against keys from this keyring;
9708 missing keys are downloaded to this keyring as well (see
9709 @option{--key-download} below.)
9711 You can export keys from your default GPG keyring into a keybox file using
9712 commands like this one:
9715 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9718 Likewise, you can fetch keys to a specific keybox file like this:
9721 gpg --no-default-keyring --keyring mykeyring.kbx \
9722 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9725 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9726 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9728 @item --key-download=@var{policy}
9729 Handle missing OpenPGP keys according to @var{policy}, which may be one
9734 Always download missing OpenPGP keys from the key server, and add them
9735 to the user's GnuPG keyring.
9738 Never try to download missing OpenPGP keys. Instead just bail out.
9741 When a package signed with an unknown OpenPGP key is encountered, ask
9742 the user whether to download it or not. This is the default behavior.
9745 @item --key-server=@var{host}
9746 Use @var{host} as the OpenPGP key server when importing a public key.
9748 @item --load-path=@var{directory}
9749 Add @var{directory} to the front of the package module search path
9750 (@pxref{Package Modules}).
9752 This allows users to define their own packages and make them visible to
9753 the command-line tools.
9757 The @code{github} updater uses the
9758 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9759 releases. When used repeatedly e.g.@: when refreshing all packages,
9760 GitHub will eventually refuse to answer any further API requests. By
9761 default 60 API requests per hour are allowed, and a full refresh on all
9762 GitHub packages in Guix requires more than this. Authentication with
9763 GitHub through the use of an API token alleviates these limits. To use
9764 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9765 token procured from @uref{https://github.com/settings/tokens} or
9769 @node Invoking guix lint
9770 @section Invoking @command{guix lint}
9772 @cindex @command{guix lint}
9773 @cindex package, checking for errors
9774 The @command{guix lint} command is meant to help package developers avoid
9775 common errors and use a consistent style. It runs a number of checks on
9776 a given set of packages in order to find common mistakes in their
9777 definitions. Available @dfn{checkers} include (see
9778 @code{--list-checkers} for a complete list):
9783 Validate certain typographical and stylistic rules about package
9784 descriptions and synopses.
9786 @item inputs-should-be-native
9787 Identify inputs that should most likely be native inputs.
9793 @itemx source-file-name
9794 Probe @code{home-page} and @code{source} URLs and report those that are
9795 invalid. Suggest a @code{mirror://} URL when applicable. If the
9796 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9797 URL. Check that the source file name is meaningful, e.g.@: is not just a
9798 version number or ``git-checkout'', without a declared @code{file-name}
9799 (@pxref{origin Reference}).
9801 @item source-unstable-tarball
9802 Parse the @code{source} URL to determine if a tarball from GitHub is
9803 autogenerated or if it is a release tarball. Unfortunately GitHub's
9804 autogenerated tarballs are sometimes regenerated.
9807 @cindex Software Heritage, source code archive
9808 @cindex archival of source code, Software Heritage
9809 Checks whether the package's source code is archived at
9810 @uref{https://www.softwareheritage.org, Software Heritage}.
9812 When the source code that is not archived comes from a version-control system
9813 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
9814 ``save'' request so that it eventually archives it. This ensures that the
9815 source will remain available in the long term, and that Guix can fall back to
9816 Software Heritage should the source code disappear from its original host.
9817 The status of recent ``save'' requests can be
9818 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
9820 When source code is a tarball obtained with @code{url-fetch}, simply print a
9821 message when it is not archived. As of this writing, Software Heritage does
9822 not allow requests to save arbitrary tarballs; we are working on ways to
9823 ensure that non-VCS source code is also archived.
9826 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
9827 request rate per IP address}. When the limit is reached, @command{guix lint}
9828 prints a message and the @code{archival} checker stops doing anything until
9829 that limit has been reset.
9832 @cindex security vulnerabilities
9833 @cindex CVE, Common Vulnerabilities and Exposures
9834 Report known vulnerabilities found in the Common Vulnerabilities and
9835 Exposures (CVE) databases of the current and past year
9836 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
9839 To view information about a particular vulnerability, visit pages such as:
9843 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9845 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9849 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9850 @code{CVE-2015-7554}.
9852 Package developers can specify in package recipes the
9853 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
9854 name and version of the package when they differ from the name or version
9855 that Guix uses, as in this example:
9861 ;; CPE calls this package "grub2".
9862 (properties '((cpe-name . "grub2")
9863 (cpe-version . "2.3"))))
9866 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9867 Some entries in the CVE database do not specify which version of a
9868 package they apply to, and would thus ``stick around'' forever. Package
9869 developers who found CVE alerts and verified they can be ignored can
9870 declare them as in this example:
9876 ;; These CVEs no longer apply and can be safely ignored.
9877 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9880 "CVE-2011-5244")))))
9884 Warn about obvious source code formatting issues: trailing white space,
9885 use of tabulations, etc.
9888 The general syntax is:
9891 guix lint @var{options} @var{package}@dots{}
9894 If no package is given on the command line, then all packages are checked.
9895 The @var{options} may be zero or more of the following:
9898 @item --list-checkers
9900 List and describe all the available checkers that will be run on packages
9905 Only enable the checkers specified in a comma-separated list using the
9906 names returned by @code{--list-checkers}.
9908 @item --load-path=@var{directory}
9909 @itemx -L @var{directory}
9910 Add @var{directory} to the front of the package module search path
9911 (@pxref{Package Modules}).
9913 This allows users to define their own packages and make them visible to
9914 the command-line tools.
9918 @node Invoking guix size
9919 @section Invoking @command{guix size}
9922 @cindex package size
9924 @cindex @command{guix size}
9925 The @command{guix size} command helps package developers profile the
9926 disk usage of packages. It is easy to overlook the impact of an
9927 additional dependency added to a package, or the impact of using a
9928 single output for a package that could easily be split (@pxref{Packages
9929 with Multiple Outputs}). Such are the typical issues that
9930 @command{guix size} can highlight.
9932 The command can be passed one or more package specifications
9933 such as @code{gcc@@4.8}
9934 or @code{guile:debug}, or a file name in the store. Consider this
9938 $ guix size coreutils
9939 store item total self
9940 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9941 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9942 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9943 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9944 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9945 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9946 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9947 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9952 The store items listed here constitute the @dfn{transitive closure} of
9953 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9954 would be returned by:
9957 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9960 Here the output shows three columns next to store items. The first column,
9961 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9962 the store item---that is, its own size plus the size of all its
9963 dependencies. The next column, labeled ``self'', shows the size of the
9964 item itself. The last column shows the ratio of the size of the item
9965 itself to the space occupied by all the items listed here.
9967 In this example, we see that the closure of Coreutils weighs in at
9968 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9969 libraries. (That libc and GCC's libraries represent a large fraction of
9970 the closure is not a problem @i{per se} because they are always available
9971 on the system anyway.)
9973 When the package(s) passed to @command{guix size} are available in the
9974 store@footnote{More precisely, @command{guix size} looks for the
9975 @emph{ungrafted} variant of the given package(s), as returned by
9976 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9977 for information on grafts.}, @command{guix size} queries the daemon to determine its
9978 dependencies, and measures its size in the store, similar to @command{du
9979 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9982 When the given packages are @emph{not} in the store, @command{guix size}
9983 reports information based on the available substitutes
9984 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9985 store items that are not even on disk, only available remotely.
9987 You can also specify several package names:
9990 $ guix size coreutils grep sed bash
9991 store item total self
9992 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9993 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9994 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9995 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
10001 In this example we see that the combination of the four packages takes
10002 102.3@tie{}MiB in total, which is much less than the sum of each closure
10003 since they have a lot of dependencies in common.
10005 The available options are:
10009 @item --substitute-urls=@var{urls}
10010 Use substitute information from @var{urls}.
10011 @xref{client-substitute-urls, the same option for @code{guix build}}.
10013 @item --sort=@var{key}
10014 Sort lines according to @var{key}, one of the following options:
10018 the size of each item (the default);
10020 the total size of the item's closure.
10023 @item --map-file=@var{file}
10024 Write a graphical map of disk usage in PNG format to @var{file}.
10026 For the example above, the map looks like this:
10028 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
10029 produced by @command{guix size}}
10031 This option requires that
10032 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
10033 installed and visible in Guile's module search path. When that is not
10034 the case, @command{guix size} fails as it tries to load it.
10036 @item --system=@var{system}
10037 @itemx -s @var{system}
10038 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
10040 @item --load-path=@var{directory}
10041 @itemx -L @var{directory}
10042 Add @var{directory} to the front of the package module search path
10043 (@pxref{Package Modules}).
10045 This allows users to define their own packages and make them visible to
10046 the command-line tools.
10049 @node Invoking guix graph
10050 @section Invoking @command{guix graph}
10053 @cindex @command{guix graph}
10054 @cindex package dependencies
10055 Packages and their dependencies form a @dfn{graph}, specifically a
10056 directed acyclic graph (DAG). It can quickly become difficult to have a
10057 mental model of the package DAG, so the @command{guix graph} command
10058 provides a visual representation of the DAG. By default,
10059 @command{guix graph} emits a DAG representation in the input format of
10060 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
10061 directly to the @command{dot} command of Graphviz. It can also emit an
10062 HTML page with embedded JavaScript code to display a ``chord diagram''
10063 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
10064 emit Cypher queries to construct a graph in a graph database supporting
10065 the @uref{https://www.opencypher.org/, openCypher} query language.
10066 The general syntax is:
10069 guix graph @var{options} @var{package}@dots{}
10072 For example, the following command generates a PDF file representing the
10073 package DAG for the GNU@tie{}Core Utilities, showing its build-time
10077 guix graph coreutils | dot -Tpdf > dag.pdf
10080 The output looks like this:
10082 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
10084 Nice little graph, no?
10086 But there is more than one graph! The one above is concise: it is the
10087 graph of package objects, omitting implicit inputs such as GCC, libc,
10088 grep, etc. It is often useful to have such a concise graph, but
10089 sometimes one may want to see more details. @command{guix graph} supports
10090 several types of graphs, allowing you to choose the level of detail:
10094 This is the default type used in the example above. It shows the DAG of
10095 package objects, excluding implicit dependencies. It is concise, but
10096 filters out many details.
10098 @item reverse-package
10099 This shows the @emph{reverse} DAG of packages. For example:
10102 guix graph --type=reverse-package ocaml
10105 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
10106 you are also interested in cases where OCaml is an implicit dependency, see
10107 @code{reverse-bag} below.)
10109 Note that for core packages this can yield huge graphs. If all you want
10110 is to know the number of packages that depend on a given package, use
10111 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
10112 @option{--list-dependent}}).
10115 This is the package DAG, @emph{including} implicit inputs.
10117 For instance, the following command:
10120 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
10123 ...@: yields this bigger graph:
10125 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
10127 At the bottom of the graph, we see all the implicit inputs of
10128 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
10130 Now, note that the dependencies of these implicit inputs---that is, the
10131 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
10132 here, for conciseness.
10135 Similar to @code{bag-emerged}, but this time including all the bootstrap
10138 @item bag-with-origins
10139 Similar to @code{bag}, but also showing origins and their dependencies.
10142 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
10143 it also takes implicit dependencies into account. For example:
10146 guix graph -t reverse-bag dune
10150 ...@: yields the graph of all packages that depend on Dune, directly or
10151 indirectly. Since Dune is an @emph{implicit} dependency of many packages
10152 @i{via} @code{dune-build-system}, this shows a large number of packages,
10153 whereas @code{reverse-package} would show very few if any.
10156 This is the most detailed representation: It shows the DAG of
10157 derivations (@pxref{Derivations}) and plain store items. Compared to
10158 the above representation, many additional nodes are visible, including
10159 build scripts, patches, Guile modules, etc.
10161 For this type of graph, it is also possible to pass a @file{.drv} file
10162 name instead of a package name, as in:
10165 guix graph -t derivation `guix system build -d my-config.scm`
10169 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
10170 For example, the following command shows the graph for the package
10171 module that defines the @code{guile} package:
10174 guix graph -t module guile | dot -Tpdf > module-graph.pdf
10178 All the types above correspond to @emph{build-time dependencies}. The
10179 following graph type represents the @emph{run-time dependencies}:
10183 This is the graph of @dfn{references} of a package output, as returned
10184 by @command{guix gc --references} (@pxref{Invoking guix gc}).
10186 If the given package output is not available in the store, @command{guix
10187 graph} attempts to obtain dependency information from substitutes.
10189 Here you can also pass a store file name instead of a package name. For
10190 example, the command below produces the reference graph of your profile
10191 (which can be big!):
10194 guix graph -t references `readlink -f ~/.guix-profile`
10198 This is the graph of the @dfn{referrers} of a store item, as returned by
10199 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
10201 This relies exclusively on local information from your store. For
10202 instance, let us suppose that the current Inkscape is available in 10
10203 profiles on your machine; @command{guix graph -t referrers inkscape}
10204 will show a graph rooted at Inkscape and with those 10 profiles linked
10207 It can help determine what is preventing a store item from being garbage
10212 The available options are the following:
10215 @item --type=@var{type}
10216 @itemx -t @var{type}
10217 Produce a graph output of @var{type}, where @var{type} must be one of
10218 the values listed above.
10221 List the supported graph types.
10223 @item --backend=@var{backend}
10224 @itemx -b @var{backend}
10225 Produce a graph using the selected @var{backend}.
10227 @item --list-backends
10228 List the supported graph backends.
10230 Currently, the available backends are Graphviz and d3.js.
10232 @item --expression=@var{expr}
10233 @itemx -e @var{expr}
10234 Consider the package @var{expr} evaluates to.
10236 This is useful to precisely refer to a package, as in this example:
10239 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
10242 @item --system=@var{system}
10243 @itemx -s @var{system}
10244 Display the graph for @var{system}---e.g., @code{i686-linux}.
10246 The package dependency graph is largely architecture-independent, but there
10247 are some architecture-dependent bits that this option allows you to visualize.
10249 @item --load-path=@var{directory}
10250 @itemx -L @var{directory}
10251 Add @var{directory} to the front of the package module search path
10252 (@pxref{Package Modules}).
10254 This allows users to define their own packages and make them visible to
10255 the command-line tools.
10258 On top of that, @command{guix graph} supports all the usual package
10259 transformation options (@pxref{Package Transformation Options}). This
10260 makes it easy to view the effect of a graph-rewriting transformation
10261 such as @option{--with-input}. For example, the command below outputs
10262 the graph of @code{git} once @code{openssl} has been replaced by
10263 @code{libressl} everywhere in the graph:
10266 guix graph git --with-input=openssl=libressl
10269 So many possibilities, so much fun!
10271 @node Invoking guix publish
10272 @section Invoking @command{guix publish}
10274 @cindex @command{guix publish}
10275 The purpose of @command{guix publish} is to enable users to easily share
10276 their store with others, who can then use it as a substitute server
10277 (@pxref{Substitutes}).
10279 When @command{guix publish} runs, it spawns an HTTP server which allows
10280 anyone with network access to obtain substitutes from it. This means
10281 that any machine running Guix can also act as if it were a build farm,
10282 since the HTTP interface is compatible with Cuirass, the software behind
10283 the @code{@value{SUBSTITUTE-SERVER}} build farm.
10285 For security, each substitute is signed, allowing recipients to check
10286 their authenticity and integrity (@pxref{Substitutes}). Because
10287 @command{guix publish} uses the signing key of the system, which is only
10288 readable by the system administrator, it must be started as root; the
10289 @code{--user} option makes it drop root privileges early on.
10291 The signing key pair must be generated before @command{guix publish} is
10292 launched, using @command{guix archive --generate-key} (@pxref{Invoking
10295 The general syntax is:
10298 guix publish @var{options}@dots{}
10301 Running @command{guix publish} without any additional arguments will
10302 spawn an HTTP server on port 8080:
10308 Once a publishing server has been authorized (@pxref{Invoking guix
10309 archive}), the daemon may download substitutes from it:
10312 guix-daemon --substitute-urls=http://example.org:8080
10315 By default, @command{guix publish} compresses archives on the fly as it
10316 serves them. This ``on-the-fly'' mode is convenient in that it requires
10317 no setup and is immediately available. However, when serving lots of
10318 clients, we recommend using the @option{--cache} option, which enables
10319 caching of the archives before they are sent to clients---see below for
10320 details. The @command{guix weather} command provides a handy way to
10321 check what a server provides (@pxref{Invoking guix weather}).
10323 As a bonus, @command{guix publish} also serves as a content-addressed
10324 mirror for source files referenced in @code{origin} records
10325 (@pxref{origin Reference}). For instance, assuming @command{guix
10326 publish} is running on @code{example.org}, the following URL returns the
10327 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
10328 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
10331 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
10334 Obviously, these URLs only work for files that are in the store; in
10335 other cases, they return 404 (``Not Found'').
10337 @cindex build logs, publication
10338 Build logs are available from @code{/log} URLs like:
10341 http://example.org/log/gwspk@dots{}-guile-2.2.3
10345 When @command{guix-daemon} is configured to save compressed build logs,
10346 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
10347 URLs return the compressed log as-is, with an appropriate
10348 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
10349 running @command{guix-daemon} with @code{--log-compression=gzip} since
10350 Web browsers can automatically decompress it, which is not the case with
10353 The following options are available:
10356 @item --port=@var{port}
10357 @itemx -p @var{port}
10358 Listen for HTTP requests on @var{port}.
10360 @item --listen=@var{host}
10361 Listen on the network interface for @var{host}. The default is to
10362 accept connections from any interface.
10364 @item --user=@var{user}
10365 @itemx -u @var{user}
10366 Change privileges to @var{user} as soon as possible---i.e., once the
10367 server socket is open and the signing key has been read.
10369 @item --compression[=@var{method}[:@var{level}]]
10370 @itemx -C [@var{method}[:@var{level}]]
10371 Compress data using the given @var{method} and @var{level}. @var{method} is
10372 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
10375 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
10376 to different compression levels: 1 is the fastest, and 9 is the best
10377 (CPU-intensive). The default is 3.
10379 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
10380 increase in CPU usage; see
10381 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
10384 Unless @option{--cache} is used, compression occurs on the fly and
10385 the compressed streams are not
10386 cached. Thus, to reduce load on the machine that runs @command{guix
10387 publish}, it may be a good idea to choose a low compression level, to
10388 run @command{guix publish} behind a caching proxy, or to use
10389 @option{--cache}. Using @option{--cache} has the advantage that it
10390 allows @command{guix publish} to add @code{Content-Length} HTTP header
10393 This option can be repeated, in which case every substitute gets compressed
10394 using all the selected methods, and all of them are advertised. This is
10395 useful when users may not support all the compression methods: they can select
10396 the one they support.
10398 @item --cache=@var{directory}
10399 @itemx -c @var{directory}
10400 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
10401 and only serve archives that are in cache.
10403 When this option is omitted, archives and meta-data are created
10404 on-the-fly. This can reduce the available bandwidth, especially when
10405 compression is enabled, since this may become CPU-bound. Another
10406 drawback of the default mode is that the length of archives is not known
10407 in advance, so @command{guix publish} does not add a
10408 @code{Content-Length} HTTP header to its responses, which in turn
10409 prevents clients from knowing the amount of data being downloaded.
10411 Conversely, when @option{--cache} is used, the first request for a store
10412 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10413 background process to @dfn{bake} the archive---computing its
10414 @code{.narinfo} and compressing the archive, if needed. Once the
10415 archive is cached in @var{directory}, subsequent requests succeed and
10416 are served directly from the cache, which guarantees that clients get
10417 the best possible bandwidth.
10419 The ``baking'' process is performed by worker threads. By default, one
10420 thread per CPU core is created, but this can be customized. See
10421 @option{--workers} below.
10423 When @option{--ttl} is used, cached entries are automatically deleted
10424 when they have expired.
10426 @item --workers=@var{N}
10427 When @option{--cache} is used, request the allocation of @var{N} worker
10428 threads to ``bake'' archives.
10430 @item --ttl=@var{ttl}
10431 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10432 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10433 days, @code{1m} means 1 month, and so on.
10435 This allows the user's Guix to keep substitute information in cache for
10436 @var{ttl}. However, note that @code{guix publish} does not itself
10437 guarantee that the store items it provides will indeed remain available
10438 for as long as @var{ttl}.
10440 Additionally, when @option{--cache} is used, cached entries that have
10441 not been accessed for @var{ttl} and that no longer have a corresponding
10442 item in the store, may be deleted.
10444 @item --nar-path=@var{path}
10445 Use @var{path} as the prefix for the URLs of ``nar'' files
10446 (@pxref{Invoking guix archive, normalized archives}).
10448 By default, nars are served at a URL such as
10449 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
10450 change the @code{/nar} part to @var{path}.
10452 @item --public-key=@var{file}
10453 @itemx --private-key=@var{file}
10454 Use the specific @var{file}s as the public/private key pair used to sign
10455 the store items being published.
10457 The files must correspond to the same key pair (the private key is used
10458 for signing and the public key is merely advertised in the signature
10459 metadata). They must contain keys in the canonical s-expression format
10460 as produced by @command{guix archive --generate-key} (@pxref{Invoking
10461 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
10462 @file{/etc/guix/signing-key.sec} are used.
10464 @item --repl[=@var{port}]
10465 @itemx -r [@var{port}]
10466 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
10467 Reference Manual}) on @var{port} (37146 by default). This is used
10468 primarily for debugging a running @command{guix publish} server.
10471 Enabling @command{guix publish} on Guix System is a one-liner: just
10472 instantiate a @code{guix-publish-service-type} service in the @code{services} field
10473 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
10474 @code{guix-publish-service-type}}).
10476 If you are instead running Guix on a ``foreign distro'', follow these
10481 If your host distro uses the systemd init system:
10484 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
10485 /etc/systemd/system/
10486 # systemctl start guix-publish && systemctl enable guix-publish
10490 If your host distro uses the Upstart init system:
10493 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
10494 # start guix-publish
10498 Otherwise, proceed similarly with your distro's init system.
10501 @node Invoking guix challenge
10502 @section Invoking @command{guix challenge}
10504 @cindex reproducible builds
10505 @cindex verifiable builds
10506 @cindex @command{guix challenge}
10508 Do the binaries provided by this server really correspond to the source
10509 code it claims to build? Is a package build process deterministic?
10510 These are the questions the @command{guix challenge} command attempts to
10513 The former is obviously an important question: Before using a substitute
10514 server (@pxref{Substitutes}), one had better @emph{verify} that it
10515 provides the right binaries, and thus @emph{challenge} it. The latter
10516 is what enables the former: If package builds are deterministic, then
10517 independent builds of the package should yield the exact same result,
10518 bit for bit; if a server provides a binary different from the one
10519 obtained locally, it may be either corrupt or malicious.
10521 We know that the hash that shows up in @file{/gnu/store} file names is
10522 the hash of all the inputs of the process that built the file or
10523 directory---compilers, libraries, build scripts,
10524 etc. (@pxref{Introduction}). Assuming deterministic build processes,
10525 one store file name should map to exactly one build output.
10526 @command{guix challenge} checks whether there is, indeed, a single
10527 mapping by comparing the build outputs of several independent builds of
10528 any given store item.
10530 The command output looks like this:
10533 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10534 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
10535 updating list of substitutes from 'https://guix.example.org'... 100.0%
10536 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
10537 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10538 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10539 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
10541 /lib/libcrypto.so.1.1
10544 /gnu/store/@dots{}-git-2.5.0 contents differ:
10545 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
10546 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
10547 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
10549 /libexec/git-core/git-fsck
10551 /gnu/store/@dots{}-pius-2.1.1 contents differ:
10552 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10553 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10554 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
10556 /share/man/man1/pius.1.gz
10560 6,406 store items were analyzed:
10561 - 4,749 (74.1%) were identical
10562 - 525 (8.2%) differed
10563 - 1,132 (17.7%) were inconclusive
10567 In this example, @command{guix challenge} first scans the store to
10568 determine the set of locally-built derivations---as opposed to store
10569 items that were downloaded from a substitute server---and then queries
10570 all the substitute servers. It then reports those store items for which
10571 the servers obtained a result different from the local build.
10573 @cindex non-determinism, in package builds
10574 As an example, @code{guix.example.org} always gets a different answer.
10575 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10576 case of Git. This might indicate that the build process of Git is
10577 non-deterministic, meaning that its output varies as a function of
10578 various things that Guix does not fully control, in spite of building
10579 packages in isolated environments (@pxref{Features}). Most common
10580 sources of non-determinism include the addition of timestamps in build
10581 results, the inclusion of random numbers, and directory listings sorted
10582 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
10585 To find out what is wrong with this Git binary, the easiest approach is
10589 guix challenge git \
10590 --diff=diffoscope \
10591 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10594 This automatically invokes @command{diffoscope}, which displays detailed
10595 information about files that differ.
10597 Alternately, we can do something along these lines (@pxref{Invoking guix
10601 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
10602 | lzip -d | guix archive -x /tmp/git
10603 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
10606 This command shows the difference between the files resulting from the
10607 local build, and the files resulting from the build on
10608 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
10609 diffutils, Comparing and Merging Files}). The @command{diff} command
10610 works great for text files. When binary files differ, a better option
10611 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
10612 visualize differences for all kinds of files.
10614 Once you have done that work, you can tell whether the differences are due
10615 to a non-deterministic build process or to a malicious server. We try
10616 hard to remove sources of non-determinism in packages to make it easier
10617 to verify substitutes, but of course, this is a process that
10618 involves not just Guix, but a large part of the free software community.
10619 In the meantime, @command{guix challenge} is one tool to help address
10622 If you are writing packages for Guix, you are encouraged to check
10623 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
10624 same build result as you did with:
10627 $ guix challenge @var{package}
10631 where @var{package} is a package specification such as
10632 @code{guile@@2.0} or @code{glibc:debug}.
10634 The general syntax is:
10637 guix challenge @var{options} [@var{packages}@dots{}]
10640 When a difference is found between the hash of a locally-built item and
10641 that of a server-provided substitute, or among substitutes provided by
10642 different servers, the command displays it as in the example above and
10643 its exit code is 2 (other non-zero exit codes denote other kinds of
10646 The one option that matters is:
10650 @item --substitute-urls=@var{urls}
10651 Consider @var{urls} the whitespace-separated list of substitute source
10652 URLs to compare to.
10654 @item --diff=@var{mode}
10655 Upon mismatches, show differences according to @var{mode}, one of:
10658 @item @code{simple} (the default)
10659 Show the list of files that differ.
10661 @item @code{diffoscope}
10662 @itemx @var{command}
10663 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
10664 two directories whose contents do not match.
10666 When @var{command} is an absolute file name, run @var{command} instead
10670 Do not show further details about the differences.
10673 Thus, unless @code{--diff=none} is passed, @command{guix challenge}
10674 downloads the store items from the given substitute servers so that it
10679 Show details about matches (identical contents) in addition to
10680 information about mismatches.
10684 @node Invoking guix copy
10685 @section Invoking @command{guix copy}
10687 @cindex copy, of store items, over SSH
10688 @cindex SSH, copy of store items
10689 @cindex sharing store items across machines
10690 @cindex transferring store items across machines
10691 The @command{guix copy} command copies items from the store of one
10692 machine to that of another machine over a secure shell (SSH)
10693 connection@footnote{This command is available only when Guile-SSH was
10694 found. @xref{Requirements}, for details.}. For example, the following
10695 command copies the @code{coreutils} package, the user's profile, and all
10696 their dependencies over to @var{host}, logged in as @var{user}:
10699 guix copy --to=@var{user}@@@var{host} \
10700 coreutils `readlink -f ~/.guix-profile`
10703 If some of the items to be copied are already present on @var{host},
10704 they are not actually sent.
10706 The command below retrieves @code{libreoffice} and @code{gimp} from
10707 @var{host}, assuming they are available there:
10710 guix copy --from=@var{host} libreoffice gimp
10713 The SSH connection is established using the Guile-SSH client, which is
10714 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10715 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10717 The key used to sign items that are sent must be accepted by the remote
10718 machine. Likewise, the key used by the remote machine to sign items you
10719 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10720 own daemon. @xref{Invoking guix archive}, for more information about
10721 store item authentication.
10723 The general syntax is:
10726 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10729 You must always specify one of the following options:
10732 @item --to=@var{spec}
10733 @itemx --from=@var{spec}
10734 Specify the host to send to or receive from. @var{spec} must be an SSH
10735 spec such as @code{example.org}, @code{charlie@@example.org}, or
10736 @code{charlie@@example.org:2222}.
10739 The @var{items} can be either package names, such as @code{gimp}, or
10740 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10742 When specifying the name of a package to send, it is first built if
10743 needed, unless @option{--dry-run} was specified. Common build options
10744 are supported (@pxref{Common Build Options}).
10747 @node Invoking guix container
10748 @section Invoking @command{guix container}
10750 @cindex @command{guix container}
10752 As of version @value{VERSION}, this tool is experimental. The interface
10753 is subject to radical change in the future.
10756 The purpose of @command{guix container} is to manipulate processes
10757 running within an isolated environment, commonly known as a
10758 ``container'', typically created by the @command{guix environment}
10759 (@pxref{Invoking guix environment}) and @command{guix system container}
10760 (@pxref{Invoking guix system}) commands.
10762 The general syntax is:
10765 guix container @var{action} @var{options}@dots{}
10768 @var{action} specifies the operation to perform with a container, and
10769 @var{options} specifies the context-specific arguments for the action.
10771 The following actions are available:
10775 Execute a command within the context of a running container.
10780 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10783 @var{pid} specifies the process ID of the running container.
10784 @var{program} specifies an executable file name within the root file
10785 system of the container. @var{arguments} are the additional options that
10786 will be passed to @var{program}.
10788 The following command launches an interactive login shell inside a
10789 Guix system container, started by @command{guix system container}, and whose
10790 process ID is 9001:
10793 guix container exec 9001 /run/current-system/profile/bin/bash --login
10796 Note that the @var{pid} cannot be the parent process of a container. It
10797 must be PID 1 of the container or one of its child processes.
10801 @node Invoking guix weather
10802 @section Invoking @command{guix weather}
10804 Occasionally you're grumpy because substitutes are lacking and you end
10805 up building packages by yourself (@pxref{Substitutes}). The
10806 @command{guix weather} command reports on substitute availability on the
10807 specified servers so you can have an idea of whether you'll be grumpy
10808 today. It can sometimes be useful info as a user, but it is primarily
10809 useful to people running @command{guix publish} (@pxref{Invoking guix
10812 @cindex statistics, for substitutes
10813 @cindex availability of substitutes
10814 @cindex substitute availability
10815 @cindex weather, substitute availability
10816 Here's a sample run:
10819 $ guix weather --substitute-urls=https://guix.example.org
10820 computing 5,872 package derivations for x86_64-linux...
10821 looking for 6,128 store items on https://guix.example.org..
10822 updating list of substitutes from 'https://guix.example.org'... 100.0%
10823 https://guix.example.org
10824 43.4% substitutes available (2,658 out of 6,128)
10825 7,032.5 MiB of nars (compressed)
10826 19,824.2 MiB on disk (uncompressed)
10827 0.030 seconds per request (182.9 seconds in total)
10828 33.5 requests per second
10830 9.8% (342 out of 3,470) of the missing items are queued
10832 x86_64-linux: 518 (59.7%)
10833 i686-linux: 221 (25.5%)
10834 aarch64-linux: 128 (14.8%)
10835 build rate: 23.41 builds per hour
10836 x86_64-linux: 11.16 builds per hour
10837 i686-linux: 6.03 builds per hour
10838 aarch64-linux: 6.41 builds per hour
10841 @cindex continuous integration, statistics
10842 As you can see, it reports the fraction of all the packages for which
10843 substitutes are available on the server---regardless of whether
10844 substitutes are enabled, and regardless of whether this server's signing
10845 key is authorized. It also reports the size of the compressed archives
10846 (``nars'') provided by the server, the size the corresponding store
10847 items occupy in the store (assuming deduplication is turned off), and
10848 the server's throughput. The second part gives continuous integration
10849 (CI) statistics, if the server supports it. In addition, using the
10850 @option{--coverage} option, @command{guix weather} can list ``important''
10851 package substitutes missing on the server (see below).
10853 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10854 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10855 challenge}, it ignores signatures on those substitutes, which is
10856 innocuous since the command only gathers statistics and cannot install
10859 The general syntax is:
10862 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10865 When @var{packages} is omitted, @command{guix weather} checks the availability
10866 of substitutes for @emph{all} the packages, or for those specified with
10867 @option{--manifest}; otherwise it only considers the specified packages. It
10868 is also possible to query specific system types with @option{--system}.
10869 @command{guix weather} exits with a non-zero code when the fraction of
10870 available substitutes is below 100%.
10872 The available options are listed below.
10875 @item --substitute-urls=@var{urls}
10876 @var{urls} is the space-separated list of substitute server URLs to
10877 query. When this option is omitted, the default set of substitute
10878 servers is queried.
10880 @item --system=@var{system}
10881 @itemx -s @var{system}
10882 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10883 option can be repeated, in which case @command{guix weather} will query
10884 substitutes for several system types.
10886 @item --manifest=@var{file}
10887 Instead of querying substitutes for all the packages, only ask for those
10888 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10889 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10892 This option can be repeated several times, in which case the manifests
10895 @item --coverage[=@var{count}]
10896 @itemx -c [@var{count}]
10897 Report on substitute coverage for packages: list packages with at least
10898 @var{count} dependents (zero by default) for which substitutes are
10899 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10900 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10901 @var{b} usually lacks substitutes as well. The result looks like this:
10904 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10905 computing 8,983 package derivations for x86_64-linux...
10906 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10907 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10908 @value{SUBSTITUTE-URL}
10909 64.7% substitutes available (6,047 out of 9,343)
10911 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10912 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10913 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10914 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10918 What this example shows is that @code{kcoreaddons} and presumably the 58
10919 packages that depend on it have no substitutes at @code{ci.guix.info};
10920 likewise for @code{qgpgme} and the 46 packages that depend on it.
10922 If you are a Guix developer, or if you are taking care of this build farm,
10923 you'll probably want to have a closer look at these packages: they may simply
10926 @item --display-missing
10927 Display the list of store items for which substitutes are missing.
10930 @node Invoking guix processes
10931 @section Invoking @command{guix processes}
10933 The @command{guix processes} command can be useful to developers and system
10934 administrators, especially on multi-user machines and on build farms: it lists
10935 the current sessions (connections to the daemon), as well as information about
10936 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10937 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10938 listed.}. Here's an example of the information it returns:
10941 $ sudo guix processes
10944 ClientCommand: guix environment --ad-hoc python
10948 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10952 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10953 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10954 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10955 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10956 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10957 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10958 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10961 In this example we see that @command{guix-daemon} has three clients:
10962 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10963 integration tool; their process identifier (PID) is given by the
10964 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10965 @command{guix-daemon} sub-process of this particular session.
10967 The @code{LockHeld} fields show which store items are currently locked by this
10968 session, which corresponds to store items being built or substituted (the
10969 @code{LockHeld} field is not displayed when @command{guix processes} is not
10970 running as root.) Last, by looking at the @code{ChildProcess} field, we
10971 understand that these three builds are being offloaded (@pxref{Daemon Offload
10974 The output is in Recutils format so we can use the handy @command{recsel}
10975 command to select sessions of interest (@pxref{Selection Expressions,,,
10976 recutils, GNU recutils manual}). As an example, the command shows the command
10977 line and PID of the client that triggered the build of a Perl package:
10980 $ sudo guix processes | \
10981 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10983 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10986 @node System Configuration
10987 @chapter System Configuration
10989 @cindex system configuration
10990 Guix System supports a consistent whole-system configuration
10991 mechanism. By that we mean that all aspects of the global system
10992 configuration---such as the available system services, timezone and
10993 locale settings, user accounts---are declared in a single place. Such
10994 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10996 One of the advantages of putting all the system configuration under the
10997 control of Guix is that it supports transactional system upgrades, and
10998 makes it possible to roll back to a previous system instantiation,
10999 should something go wrong with the new one (@pxref{Features}). Another
11000 advantage is that it makes it easy to replicate the exact same configuration
11001 across different machines, or at different points in time, without
11002 having to resort to additional administration tools layered on top of
11003 the own tools of the system.
11004 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
11006 This section describes this mechanism. First we focus on the system
11007 administrator's viewpoint---explaining how the system is configured and
11008 instantiated. Then we show how this mechanism can be extended, for
11009 instance to support new system services.
11012 * Using the Configuration System:: Customizing your GNU system.
11013 * operating-system Reference:: Detail of operating-system declarations.
11014 * File Systems:: Configuring file system mounts.
11015 * Mapped Devices:: Block device extra processing.
11016 * User Accounts:: Specifying user accounts.
11017 * Keyboard Layout:: How the system interprets key strokes.
11018 * Locales:: Language and cultural convention settings.
11019 * Services:: Specifying system services.
11020 * Setuid Programs:: Programs running with root privileges.
11021 * X.509 Certificates:: Authenticating HTTPS servers.
11022 * Name Service Switch:: Configuring libc's name service switch.
11023 * Initial RAM Disk:: Linux-Libre bootstrapping.
11024 * Bootloader Configuration:: Configuring the boot loader.
11025 * Invoking guix system:: Instantiating a system configuration.
11026 * Invoking guix deploy:: Deploying a system configuration to a remote host.
11027 * Running Guix in a VM:: How to run Guix System in a virtual machine.
11028 * Defining Services:: Adding new service definitions.
11031 @node Using the Configuration System
11032 @section Using the Configuration System
11034 The operating system is configured by providing an
11035 @code{operating-system} declaration in a file that can then be passed to
11036 the @command{guix system} command (@pxref{Invoking guix system}). A
11037 simple setup, with the default system services, the default Linux-Libre
11038 kernel, initial RAM disk, and boot loader looks like this:
11040 @findex operating-system
11042 @include os-config-bare-bones.texi
11045 This example should be self-describing. Some of the fields defined
11046 above, such as @code{host-name} and @code{bootloader}, are mandatory.
11047 Others, such as @code{packages} and @code{services}, can be omitted, in
11048 which case they get a default value.
11050 Below we discuss the effect of some of the most important fields
11051 (@pxref{operating-system Reference}, for details about all the available
11052 fields), and how to @dfn{instantiate} the operating system using
11053 @command{guix system}.
11055 @unnumberedsubsec Bootloader
11057 @cindex legacy boot, on Intel machines
11058 @cindex BIOS boot, on Intel machines
11061 The @code{bootloader} field describes the method that will be used to boot
11062 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
11063 mode, as in the example above. However, more recent machines rely instead on
11064 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
11065 the @code{bootloader} field should contain something along these lines:
11068 (bootloader-configuration
11069 (bootloader grub-efi-bootloader)
11070 (target "/boot/efi"))
11073 @xref{Bootloader Configuration}, for more information on the available
11074 configuration options.
11076 @unnumberedsubsec Globally-Visible Packages
11078 @vindex %base-packages
11079 The @code{packages} field lists packages that will be globally visible
11080 on the system, for all user accounts---i.e., in every user's @code{PATH}
11081 environment variable---in addition to the per-user profiles
11082 (@pxref{Invoking guix package}). The @code{%base-packages} variable
11083 provides all the tools one would expect for basic user and administrator
11084 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
11085 the GNU Zile lightweight text editor, @command{find}, @command{grep},
11086 etc. The example above adds GNU@tie{}Screen to those,
11087 taken from the @code{(gnu packages screen)}
11088 module (@pxref{Package Modules}). The
11089 @code{(list package output)} syntax can be used to add a specific output
11093 (use-modules (gnu packages))
11094 (use-modules (gnu packages dns))
11098 (packages (cons (list bind "utils")
11102 @findex specification->package
11103 Referring to packages by variable name, like @code{bind} above, has
11104 the advantage of being unambiguous; it also allows typos and such to be
11105 diagnosed right away as ``unbound variables''. The downside is that one
11106 needs to know which module defines which package, and to augment the
11107 @code{use-package-modules} line accordingly. To avoid that, one can use
11108 the @code{specification->package} procedure of the @code{(gnu packages)}
11109 module, which returns the best package for a given name or name and
11113 (use-modules (gnu packages))
11117 (packages (append (map specification->package
11118 '("tcpdump" "htop" "gnupg@@2.0"))
11122 @unnumberedsubsec System Services
11125 @vindex %base-services
11126 The @code{services} field lists @dfn{system services} to be made
11127 available when the system starts (@pxref{Services}).
11128 The @code{operating-system} declaration above specifies that, in
11129 addition to the basic services, we want the OpenSSH secure shell
11130 daemon listening on port 2222 (@pxref{Networking Services,
11131 @code{openssh-service-type}}). Under the hood,
11132 @code{openssh-service-type} arranges so that @command{sshd} is started with the
11133 right command-line options, possibly with supporting configuration files
11134 generated as needed (@pxref{Defining Services}).
11136 @cindex customization, of services
11137 @findex modify-services
11138 Occasionally, instead of using the base services as is, you will want to
11139 customize them. To do this, use @code{modify-services} (@pxref{Service
11140 Reference, @code{modify-services}}) to modify the list.
11142 For example, suppose you want to modify @code{guix-daemon} and Mingetty
11143 (the console log-in) in the @code{%base-services} list (@pxref{Base
11144 Services, @code{%base-services}}). To do that, you can write the
11145 following in your operating system declaration:
11148 (define %my-services
11149 ;; My very own list of services.
11150 (modify-services %base-services
11151 (guix-service-type config =>
11152 (guix-configuration
11154 (use-substitutes? #f)
11155 (extra-options '("--gc-keep-derivations"))))
11156 (mingetty-service-type config =>
11157 (mingetty-configuration
11158 (inherit config)))))
11162 (services %my-services))
11165 This changes the configuration---i.e., the service parameters---of the
11166 @code{guix-service-type} instance, and that of all the
11167 @code{mingetty-service-type} instances in the @code{%base-services} list.
11168 Observe how this is accomplished: first, we arrange for the original
11169 configuration to be bound to the identifier @code{config} in the
11170 @var{body}, and then we write the @var{body} so that it evaluates to the
11171 desired configuration. In particular, notice how we use @code{inherit}
11172 to create a new configuration which has the same values as the old
11173 configuration, but with a few modifications.
11175 @cindex encrypted disk
11176 The configuration for a typical ``desktop'' usage, with an encrypted
11177 root partition, the X11 display
11178 server, GNOME and Xfce (users can choose which of these desktop
11179 environments to use at the log-in screen by pressing @kbd{F1}), network
11180 management, power management, and more, would look like this:
11183 @include os-config-desktop.texi
11186 A graphical system with a choice of lightweight window managers
11187 instead of full-blown desktop environments would look like this:
11190 @include os-config-lightweight-desktop.texi
11193 This example refers to the @file{/boot/efi} file system by its UUID,
11194 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
11195 as returned by the @command{blkid} command.
11197 @xref{Desktop Services}, for the exact list of services provided by
11198 @code{%desktop-services}. @xref{X.509 Certificates}, for background
11199 information about the @code{nss-certs} package that is used here.
11201 Again, @code{%desktop-services} is just a list of service objects. If
11202 you want to remove services from there, you can do so using the
11203 procedures for list filtering (@pxref{SRFI-1 Filtering and
11204 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
11205 following expression returns a list that contains all the services in
11206 @code{%desktop-services} minus the Avahi service:
11209 (remove (lambda (service)
11210 (eq? (service-kind service) avahi-service-type))
11214 @unnumberedsubsec Instantiating the System
11216 Assuming the @code{operating-system} declaration
11217 is stored in the @file{my-system-config.scm}
11218 file, the @command{guix system reconfigure my-system-config.scm} command
11219 instantiates that configuration, and makes it the default GRUB boot
11220 entry (@pxref{Invoking guix system}).
11222 The normal way to change the system configuration is by updating this
11223 file and re-running @command{guix system reconfigure}. One should never
11224 have to touch files in @file{/etc} or to run commands that modify the
11225 system state such as @command{useradd} or @command{grub-install}. In
11226 fact, you must avoid that since that would not only void your warranty
11227 but also prevent you from rolling back to previous versions of your
11228 system, should you ever need to.
11230 @cindex roll-back, of the operating system
11231 Speaking of roll-back, each time you run @command{guix system
11232 reconfigure}, a new @dfn{generation} of the system is created---without
11233 modifying or deleting previous generations. Old system generations get
11234 an entry in the bootloader boot menu, allowing you to boot them in case
11235 something went wrong with the latest generation. Reassuring, no? The
11236 @command{guix system list-generations} command lists the system
11237 generations available on disk. It is also possible to roll back the
11238 system via the commands @command{guix system roll-back} and
11239 @command{guix system switch-generation}.
11241 Although the @command{guix system reconfigure} command will not modify
11242 previous generations, you must take care when the current generation is not
11243 the latest (e.g., after invoking @command{guix system roll-back}), since
11244 the operation might overwrite a later generation (@pxref{Invoking guix
11247 @unnumberedsubsec The Programming Interface
11249 At the Scheme level, the bulk of an @code{operating-system} declaration
11250 is instantiated with the following monadic procedure (@pxref{The Store
11253 @deffn {Monadic Procedure} operating-system-derivation os
11254 Return a derivation that builds @var{os}, an @code{operating-system}
11255 object (@pxref{Derivations}).
11257 The output of the derivation is a single directory that refers to all
11258 the packages, configuration files, and other supporting files needed to
11259 instantiate @var{os}.
11262 This procedure is provided by the @code{(gnu system)} module. Along
11263 with @code{(gnu services)} (@pxref{Services}), this module contains the
11264 guts of Guix System. Make sure to visit it!
11267 @node operating-system Reference
11268 @section @code{operating-system} Reference
11270 This section summarizes all the options available in
11271 @code{operating-system} declarations (@pxref{Using the Configuration
11274 @deftp {Data Type} operating-system
11275 This is the data type representing an operating system configuration.
11276 By that, we mean all the global system configuration, not per-user
11277 configuration (@pxref{Using the Configuration System}).
11280 @item @code{kernel} (default: @code{linux-libre})
11281 The package object of the operating system kernel to use@footnote{Currently
11282 only the Linux-libre kernel is supported. In the future, it will be
11283 possible to use the GNU@tie{}Hurd.}.
11285 @item @code{kernel-loadable-modules} (default: '())
11286 A list of objects (usually packages) to collect loadable kernel modules
11287 from--e.g. @code{(list ddcci-driver-linux)}.
11289 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
11290 List of strings or gexps representing additional arguments to pass on
11291 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
11293 @item @code{bootloader}
11294 The system bootloader configuration object. @xref{Bootloader Configuration}.
11297 This is the label (a string) as it appears in the bootloader's menu entry.
11298 The default label includes the kernel name and version.
11300 @item @code{keyboard-layout} (default: @code{#f})
11301 This field specifies the keyboard layout to use in the console. It can be
11302 either @code{#f}, in which case the default keyboard layout is used (usually
11303 US English), or a @code{<keyboard-layout>} record.
11305 This keyboard layout is in effect as soon as the kernel has booted. For
11306 instance, it is the keyboard layout in effect when you type a passphrase if
11307 your root file system is on a @code{luks-device-mapping} mapped device
11308 (@pxref{Mapped Devices}).
11311 This does @emph{not} specify the keyboard layout used by the bootloader, nor
11312 that used by the graphical display server. @xref{Bootloader Configuration},
11313 for information on how to specify the bootloader's keyboard layout. @xref{X
11314 Window}, for information on how to specify the keyboard layout used by the X
11318 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
11320 @cindex initial RAM disk
11321 The list of Linux kernel modules that need to be available in the
11322 initial RAM disk. @xref{Initial RAM Disk}.
11324 @item @code{initrd} (default: @code{base-initrd})
11325 A procedure that returns an initial RAM disk for the Linux
11326 kernel. This field is provided to support low-level customization and
11327 should rarely be needed for casual use. @xref{Initial RAM Disk}.
11329 @item @code{firmware} (default: @code{%base-firmware})
11331 List of firmware packages loadable by the operating system kernel.
11333 The default includes firmware needed for Atheros- and Broadcom-based
11334 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
11335 respectively). @xref{Hardware Considerations}, for more info on
11336 supported hardware.
11338 @item @code{host-name}
11341 @item @code{hosts-file}
11343 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
11344 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
11345 Reference Manual}). The default is a file with entries for
11346 @code{localhost} and @var{host-name}.
11348 @item @code{mapped-devices} (default: @code{'()})
11349 A list of mapped devices. @xref{Mapped Devices}.
11351 @item @code{file-systems}
11352 A list of file systems. @xref{File Systems}.
11354 @item @code{swap-devices} (default: @code{'()})
11355 @cindex swap devices
11356 A list of strings identifying devices or files to be used for ``swap
11357 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
11358 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
11359 It is possible to specify a swap file in a file system on a mapped
11360 device, provided that the necessary device mapping and file system are
11361 also specified. @xref{Mapped Devices} and @ref{File Systems}.
11363 @item @code{users} (default: @code{%base-user-accounts})
11364 @itemx @code{groups} (default: @code{%base-groups})
11365 List of user accounts and groups. @xref{User Accounts}.
11367 If the @code{users} list lacks a user account with UID@tie{}0, a
11368 ``root'' account with UID@tie{}0 is automatically added.
11370 @item @code{skeletons} (default: @code{(default-skeletons)})
11371 A list target file name/file-like object tuples (@pxref{G-Expressions,
11372 file-like objects}). These are the skeleton files that will be added to
11373 the home directory of newly-created user accounts.
11375 For instance, a valid value may look like this:
11378 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
11379 (".guile" ,(plain-file "guile"
11380 "(use-modules (ice-9 readline))
11381 (activate-readline)")))
11384 @item @code{issue} (default: @code{%default-issue})
11385 A string denoting the contents of the @file{/etc/issue} file, which is
11386 displayed when users log in on a text console.
11388 @item @code{packages} (default: @code{%base-packages})
11389 The set of packages installed in the global profile, which is accessible
11390 at @file{/run/current-system/profile}.
11392 The default set includes core utilities and it is good practice to
11393 install non-core utilities in user profiles (@pxref{Invoking guix
11396 @item @code{timezone}
11397 A timezone identifying string---e.g., @code{"Europe/Paris"}.
11399 You can run the @command{tzselect} command to find out which timezone
11400 string corresponds to your region. Choosing an invalid timezone name
11401 causes @command{guix system} to fail.
11403 @item @code{locale} (default: @code{"en_US.utf8"})
11404 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
11405 Library Reference Manual}). @xref{Locales}, for more information.
11407 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
11408 The list of locale definitions to be compiled and that may be used at
11409 run time. @xref{Locales}.
11411 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
11412 The list of GNU@tie{}libc packages whose locale data and tools are used
11413 to build the locale definitions. @xref{Locales}, for compatibility
11414 considerations that justify this option.
11416 @item @code{name-service-switch} (default: @code{%default-nss})
11417 Configuration of the libc name service switch (NSS)---a
11418 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
11421 @item @code{services} (default: @code{%base-services})
11422 A list of service objects denoting system services. @xref{Services}.
11424 @cindex essential services
11425 @item @code{essential-services} (default: ...)
11426 The list of ``essential services''---i.e., things like instances of
11427 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
11428 Reference}), which are derived from the operating system definition itself.
11429 As a user you should @emph{never} need to touch this field.
11431 @item @code{pam-services} (default: @code{(base-pam-services)})
11433 @cindex pluggable authentication modules
11434 Linux @dfn{pluggable authentication module} (PAM) services.
11435 @c FIXME: Add xref to PAM services section.
11437 @item @code{setuid-programs} (default: @code{%setuid-programs})
11438 List of string-valued G-expressions denoting setuid programs.
11439 @xref{Setuid Programs}.
11441 @item @code{sudoers-file} (default: @code{%sudoers-specification})
11442 @cindex sudoers file
11443 The contents of the @file{/etc/sudoers} file as a file-like object
11444 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
11446 This file specifies which users can use the @command{sudo} command, what
11447 they are allowed to do, and what privileges they may gain. The default
11448 is that only @code{root} and members of the @code{wheel} group may use
11453 @deffn {Scheme Syntax} this-operating-system
11454 When used in the @emph{lexical scope} of an operating system field definition,
11455 this identifier resolves to the operating system being defined.
11457 The example below shows how to refer to the operating system being defined in
11458 the definition of the @code{label} field:
11461 (use-modules (gnu) (guix))
11465 (label (package-full-name
11466 (operating-system-kernel this-operating-system))))
11469 It is an error to refer to @code{this-operating-system} outside an operating
11476 @section File Systems
11478 The list of file systems to be mounted is specified in the
11479 @code{file-systems} field of the operating system declaration
11480 (@pxref{Using the Configuration System}). Each file system is declared
11481 using the @code{file-system} form, like this:
11485 (mount-point "/home")
11486 (device "/dev/sda3")
11490 As usual, some of the fields are mandatory---those shown in the example
11491 above---while others can be omitted. These are described below.
11493 @deftp {Data Type} file-system
11494 Objects of this type represent file systems to be mounted. They
11495 contain the following members:
11499 This is a string specifying the type of the file system---e.g.,
11502 @item @code{mount-point}
11503 This designates the place where the file system is to be mounted.
11505 @item @code{device}
11506 This names the ``source'' of the file system. It can be one of three
11507 things: a file system label, a file system UUID, or the name of a
11508 @file{/dev} node. Labels and UUIDs offer a way to refer to file
11509 systems without having to hard-code their actual device
11510 name@footnote{Note that, while it is tempting to use
11511 @file{/dev/disk/by-uuid} and similar device names to achieve the same
11512 result, this is not recommended: These special device nodes are created
11513 by the udev daemon and may be unavailable at the time the device is
11516 @findex file-system-label
11517 File system labels are created using the @code{file-system-label}
11518 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
11519 plain strings. Here's an example of a file system referred to by its
11520 label, as shown by the @command{e2label} command:
11524 (mount-point "/home")
11526 (device (file-system-label "my-home")))
11530 UUIDs are converted from their string representation (as shown by the
11531 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
11532 @code{uuid} form expects 16-byte UUIDs as defined in
11533 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
11534 form of UUID used by the ext2 family of file systems and others, but it
11535 is different from ``UUIDs'' found in FAT file systems, for instance.},
11540 (mount-point "/home")
11542 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
11545 When the source of a file system is a mapped device (@pxref{Mapped
11546 Devices}), its @code{device} field @emph{must} refer to the mapped
11547 device name---e.g., @file{"/dev/mapper/root-partition"}.
11548 This is required so that
11549 the system knows that mounting the file system depends on having the
11550 corresponding device mapping established.
11552 @item @code{flags} (default: @code{'()})
11553 This is a list of symbols denoting mount flags. Recognized flags
11554 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
11555 access to special files), @code{no-suid} (ignore setuid and setgid
11556 bits), @code{no-atime} (do not update file access times),
11557 @code{strict-atime} (update file access time), @code{lazy-time} (only
11558 update time on the in-memory version of the file inode), and
11559 @code{no-exec} (disallow program execution).
11560 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
11561 Manual}, for more information on these flags.
11563 @item @code{options} (default: @code{#f})
11564 This is either @code{#f}, or a string denoting mount options passed to the
11565 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
11566 Reference Manual}, for details and run @command{man 8 mount} for options for
11567 various file systems.
11569 @item @code{mount?} (default: @code{#t})
11570 This value indicates whether to automatically mount the file system when
11571 the system is brought up. When set to @code{#f}, the file system gets
11572 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
11573 is not automatically mounted.
11575 @item @code{needed-for-boot?} (default: @code{#f})
11576 This Boolean value indicates whether the file system is needed when
11577 booting. If that is true, then the file system is mounted when the
11578 initial RAM disk (initrd) is loaded. This is always the case, for
11579 instance, for the root file system.
11581 @item @code{check?} (default: @code{#t})
11582 This Boolean indicates whether the file system needs to be checked for
11583 errors before being mounted.
11585 @item @code{create-mount-point?} (default: @code{#f})
11586 When true, the mount point is created if it does not exist yet.
11588 @item @code{dependencies} (default: @code{'()})
11589 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
11590 representing file systems that must be mounted or mapped devices that
11591 must be opened before (and unmounted or closed after) this one.
11593 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
11594 a dependency of @file{/sys/fs/cgroup/cpu} and
11595 @file{/sys/fs/cgroup/memory}.
11597 Another example is a file system that depends on a mapped device, for
11598 example for an encrypted partition (@pxref{Mapped Devices}).
11602 The @code{(gnu system file-systems)} exports the following useful
11605 @defvr {Scheme Variable} %base-file-systems
11606 These are essential file systems that are required on normal systems,
11607 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
11608 below.) Operating system declarations should always contain at least
11612 @defvr {Scheme Variable} %pseudo-terminal-file-system
11613 This is the file system to be mounted as @file{/dev/pts}. It supports
11614 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
11615 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
11616 Manual}). Pseudo-terminals are used by terminal emulators such as
11620 @defvr {Scheme Variable} %shared-memory-file-system
11621 This file system is mounted as @file{/dev/shm} and is used to support
11622 memory sharing across processes (@pxref{Memory-mapped I/O,
11623 @code{shm_open},, libc, The GNU C Library Reference Manual}).
11626 @defvr {Scheme Variable} %immutable-store
11627 This file system performs a read-only ``bind mount'' of
11628 @file{/gnu/store}, making it read-only for all the users including
11629 @code{root}. This prevents against accidental modification by software
11630 running as @code{root} or by system administrators.
11632 The daemon itself is still able to write to the store: it remounts it
11633 read-write in its own ``name space.''
11636 @defvr {Scheme Variable} %binary-format-file-system
11637 The @code{binfmt_misc} file system, which allows handling of arbitrary
11638 executable file types to be delegated to user space. This requires the
11639 @code{binfmt.ko} kernel module to be loaded.
11642 @defvr {Scheme Variable} %fuse-control-file-system
11643 The @code{fusectl} file system, which allows unprivileged users to mount
11644 and unmount user-space FUSE file systems. This requires the
11645 @code{fuse.ko} kernel module to be loaded.
11648 @node Mapped Devices
11649 @section Mapped Devices
11651 @cindex device mapping
11652 @cindex mapped devices
11653 The Linux kernel has a notion of @dfn{device mapping}: a block device,
11654 such as a hard disk partition, can be @dfn{mapped} into another device,
11655 usually in @code{/dev/mapper/},
11656 with additional processing over the data that flows through
11657 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
11658 concept of a ``mapped device'' and that of a file system: both boil down
11659 to @emph{translating} input/output operations made on a file to
11660 operations on its backing store. Thus, the Hurd implements mapped
11661 devices, like file systems, using the generic @dfn{translator} mechanism
11662 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
11663 typical example is encryption device mapping: all writes to the mapped
11664 device are encrypted, and all reads are deciphered, transparently.
11665 Guix extends this notion by considering any device or set of devices that
11666 are @dfn{transformed} in some way to create a new device; for instance,
11667 RAID devices are obtained by @dfn{assembling} several other devices, such
11668 as hard disks or partitions, into a new one that behaves as one partition.
11669 Other examples, not yet implemented, are LVM logical volumes.
11671 Mapped devices are declared using the @code{mapped-device} form,
11672 defined as follows; for examples, see below.
11674 @deftp {Data Type} mapped-device
11675 Objects of this type represent device mappings that will be made when
11676 the system boots up.
11680 This is either a string specifying the name of the block device to be mapped,
11681 such as @code{"/dev/sda3"}, or a list of such strings when several devices
11682 need to be assembled for creating a new one.
11685 This string specifies the name of the resulting mapped device. For
11686 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
11687 specifying @code{"my-partition"} leads to the creation of
11688 the @code{"/dev/mapper/my-partition"} device.
11689 For RAID devices of type @code{raid-device-mapping}, the full device name
11690 such as @code{"/dev/md0"} needs to be given.
11693 This must be a @code{mapped-device-kind} object, which specifies how
11694 @var{source} is mapped to @var{target}.
11698 @defvr {Scheme Variable} luks-device-mapping
11699 This defines LUKS block device encryption using the @command{cryptsetup}
11700 command from the package with the same name. It relies on the
11701 @code{dm-crypt} Linux kernel module.
11704 @defvr {Scheme Variable} raid-device-mapping
11705 This defines a RAID device, which is assembled using the @code{mdadm}
11706 command from the package with the same name. It requires a Linux kernel
11707 module for the appropriate RAID level to be loaded, such as @code{raid456}
11708 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
11711 @cindex disk encryption
11713 The following example specifies a mapping from @file{/dev/sda3} to
11714 @file{/dev/mapper/home} using LUKS---the
11715 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
11716 standard mechanism for disk encryption.
11717 The @file{/dev/mapper/home}
11718 device can then be used as the @code{device} of a @code{file-system}
11719 declaration (@pxref{File Systems}).
11723 (source "/dev/sda3")
11725 (type luks-device-mapping))
11728 Alternatively, to become independent of device numbering, one may obtain
11729 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11733 cryptsetup luksUUID /dev/sda3
11736 and use it as follows:
11740 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11742 (type luks-device-mapping))
11745 @cindex swap encryption
11746 It is also desirable to encrypt swap space, since swap space may contain
11747 sensitive data. One way to accomplish that is to use a swap file in a
11748 file system on a device mapped via LUKS encryption. In this way, the
11749 swap file is encrypted because the entire device is encrypted.
11750 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11752 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11753 may be declared as follows:
11757 (source (list "/dev/sda1" "/dev/sdb1"))
11758 (target "/dev/md0")
11759 (type raid-device-mapping))
11762 The @file{/dev/md0} device can then be used as the @code{device} of a
11763 @code{file-system} declaration (@pxref{File Systems}).
11764 Note that the RAID level need not be given; it is chosen during the
11765 initial creation and formatting of the RAID device and is determined
11766 automatically later.
11769 @node User Accounts
11770 @section User Accounts
11774 @cindex user accounts
11775 User accounts and groups are entirely managed through the
11776 @code{operating-system} declaration. They are specified with the
11777 @code{user-account} and @code{user-group} forms:
11783 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11784 "audio" ;sound card
11785 "video" ;video devices such as webcams
11786 "cdrom")) ;the good ol' CD-ROM
11787 (comment "Bob's sister")
11788 (home-directory "/home/alice"))
11791 When booting or upon completion of @command{guix system reconfigure},
11792 the system ensures that only the user accounts and groups specified in
11793 the @code{operating-system} declaration exist, and with the specified
11794 properties. Thus, account or group creations or modifications made by
11795 directly invoking commands such as @command{useradd} are lost upon
11796 reconfiguration or reboot. This ensures that the system remains exactly
11799 @deftp {Data Type} user-account
11800 Objects of this type represent user accounts. The following members may
11805 The name of the user account.
11809 This is the name (a string) or identifier (a number) of the user group
11810 this account belongs to.
11812 @item @code{supplementary-groups} (default: @code{'()})
11813 Optionally, this can be defined as a list of group names that this
11814 account belongs to.
11816 @item @code{uid} (default: @code{#f})
11817 This is the user ID for this account (a number), or @code{#f}. In the
11818 latter case, a number is automatically chosen by the system when the
11819 account is created.
11821 @item @code{comment} (default: @code{""})
11822 A comment about the account, such as the account owner's full name.
11824 @item @code{home-directory}
11825 This is the name of the home directory for the account.
11827 @item @code{create-home-directory?} (default: @code{#t})
11828 Indicates whether the home directory of this account should be created
11829 if it does not exist yet.
11831 @item @code{shell} (default: Bash)
11832 This is a G-expression denoting the file name of a program to be used as
11833 the shell (@pxref{G-Expressions}).
11835 @item @code{system?} (default: @code{#f})
11836 This Boolean value indicates whether the account is a ``system''
11837 account. System accounts are sometimes treated specially; for instance,
11838 graphical login managers do not list them.
11840 @anchor{user-account-password}
11841 @cindex password, for user accounts
11842 @item @code{password} (default: @code{#f})
11843 You would normally leave this field to @code{#f}, initialize user
11844 passwords as @code{root} with the @command{passwd} command, and then let
11845 users change it with @command{passwd}. Passwords set with
11846 @command{passwd} are of course preserved across reboot and
11849 If you @emph{do} want to set an initial password for an account, then
11850 this field must contain the encrypted password, as a string. You can use the
11851 @code{crypt} procedure for this purpose:
11858 ;; Specify a SHA-512-hashed initial password.
11859 (password (crypt "InitialPassword!" "$6$abc")))
11863 The hash of this initial password will be available in a file in
11864 @file{/gnu/store}, readable by all the users, so this method must be used with
11868 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11869 more information on password encryption, and @ref{Encryption,,, guile, GNU
11870 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11876 User group declarations are even simpler:
11879 (user-group (name "students"))
11882 @deftp {Data Type} user-group
11883 This type is for, well, user groups. There are just a few fields:
11887 The name of the group.
11889 @item @code{id} (default: @code{#f})
11890 The group identifier (a number). If @code{#f}, a new number is
11891 automatically allocated when the group is created.
11893 @item @code{system?} (default: @code{#f})
11894 This Boolean value indicates whether the group is a ``system'' group.
11895 System groups have low numerical IDs.
11897 @item @code{password} (default: @code{#f})
11898 What, user groups can have a password? Well, apparently yes. Unless
11899 @code{#f}, this field specifies the password of the group.
11904 For convenience, a variable lists all the basic user groups one may
11907 @defvr {Scheme Variable} %base-groups
11908 This is the list of basic user groups that users and/or packages expect
11909 to be present on the system. This includes groups such as ``root'',
11910 ``wheel'', and ``users'', as well as groups used to control access to
11911 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11914 @defvr {Scheme Variable} %base-user-accounts
11915 This is the list of basic system accounts that programs may expect to
11916 find on a GNU/Linux system, such as the ``nobody'' account.
11918 Note that the ``root'' account is not included here. It is a
11919 special-case and is automatically added whether or not it is specified.
11922 @node Keyboard Layout
11923 @section Keyboard Layout
11925 @cindex keyboard layout
11927 To specify what each key of your keyboard does, you need to tell the operating
11928 system what @dfn{keyboard layout} you want to use. The default, when nothing
11929 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11930 However, German speakers will usually prefer the German QWERTZ layout, French
11931 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11932 or bépo, and they might even want to further customize the effect of some of
11933 the keys. This section explains how to get that done.
11935 @cindex keyboard layout, definition
11936 There are three components that will want to know about your keyboard layout:
11940 The @emph{bootloader} may want to know what keyboard layout you want to use
11941 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11942 you want, for instance, to make sure that you can type the passphrase of your
11943 encrypted root partition using the right layout.
11946 The @emph{operating system kernel}, Linux, will need that so that the console
11947 is properly configured (@pxref{operating-system Reference,
11948 @code{keyboard-layout}}).
11951 The @emph{graphical display server}, usually Xorg, also has its own idea of
11952 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11955 Guix allows you to configure all three separately but, fortunately, it allows
11956 you to share the same keyboard layout for all three components.
11958 @cindex XKB, keyboard layouts
11959 Keyboard layouts are represented by records created by the
11960 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11961 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11962 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11963 optional variant name, an optional keyboard model name, and a possibly empty
11964 list of additional options. In most cases the layout name is all you care
11965 about. Here are a few example:
11968 ;; The German QWERTZ layout. Here we assume a standard
11969 ;; "pc105" keyboard model.
11970 (keyboard-layout "de")
11972 ;; The bépo variant of the French layout.
11973 (keyboard-layout "fr" "bepo")
11975 ;; The Catalan layout.
11976 (keyboard-layout "es" "cat")
11978 ;; Arabic layout with "Alt-Shift" to switch to US layout.
11979 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
11981 ;; The Latin American Spanish layout. In addition, the
11982 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11983 ;; and the "Menu" key is used as a "Compose" key to enter
11984 ;; accented letters.
11985 (keyboard-layout "latam"
11986 #:options '("ctrl:nocaps" "compose:menu"))
11988 ;; The Russian layout for a ThinkPad keyboard.
11989 (keyboard-layout "ru" #:model "thinkpad")
11991 ;; The "US international" layout, which is the US layout plus
11992 ;; dead keys to enter accented characters. This is for an
11993 ;; Apple MacBook keyboard.
11994 (keyboard-layout "us" "intl" #:model "macbook78")
11997 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11998 for a complete list of supported layouts, variants, and models.
12000 @cindex keyboard layout, configuration
12001 Let's say you want your system to use the Turkish keyboard layout throughout
12002 your system---bootloader, console, and Xorg. Here's what your system
12003 configuration would look like:
12005 @findex set-xorg-configuration
12007 ;; Using the Turkish layout for the bootloader, the console,
12012 (keyboard-layout (keyboard-layout "tr")) ;for the console
12013 (bootloader (bootloader-configuration
12014 (bootloader grub-efi-bootloader)
12015 (target "/boot/efi")
12016 (keyboard-layout keyboard-layout))) ;for GRUB
12017 (services (cons (set-xorg-configuration
12018 (xorg-configuration ;for Xorg
12019 (keyboard-layout keyboard-layout)))
12020 %desktop-services)))
12023 In the example above, for GRUB and for Xorg, we just refer to the
12024 @code{keyboard-layout} field defined above, but we could just as well refer to
12025 a different layout. The @code{set-xorg-configuration} procedure communicates
12026 the desired Xorg configuration to the graphical log-in manager, by default
12029 We've discussed how to specify the @emph{default} keyboard layout of your
12030 system when it starts, but you can also adjust it at run time:
12034 If you're using GNOME, its settings panel has a ``Region & Language'' entry
12035 where you can select one or more keyboard layouts.
12038 Under Xorg, the @command{setxkbmap} command (from the same-named package)
12039 allows you to change the current layout. For example, this is how you would
12040 change the layout to US Dvorak:
12043 setxkbmap us dvorak
12047 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
12048 console. However, note that @code{loadkeys} does @emph{not} use the XKB
12049 keyboard layout categorization described above. The command below loads the
12050 French bépo layout:
12061 A @dfn{locale} defines cultural conventions for a particular language
12062 and region of the world (@pxref{Locales,,, libc, The GNU C Library
12063 Reference Manual}). Each locale has a name that typically has the form
12064 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
12065 @code{fr_LU.utf8} designates the locale for the French language, with
12066 cultural conventions from Luxembourg, and using the UTF-8 encoding.
12068 @cindex locale definition
12069 Usually, you will want to specify the default locale for the machine
12070 using the @code{locale} field of the @code{operating-system} declaration
12071 (@pxref{operating-system Reference, @code{locale}}).
12073 The selected locale is automatically added to the @dfn{locale
12074 definitions} known to the system if needed, with its codeset inferred
12075 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
12076 @code{UTF-8} codeset. Additional locale definitions can be specified in
12077 the @code{locale-definitions} slot of @code{operating-system}---this is
12078 useful, for instance, if the codeset could not be inferred from the
12079 locale name. The default set of locale definitions includes some widely
12080 used locales, but not all the available locales, in order to save space.
12082 For instance, to add the North Frisian locale for Germany, the value of
12086 (cons (locale-definition
12087 (name "fy_DE.utf8") (source "fy_DE"))
12088 %default-locale-definitions)
12091 Likewise, to save space, one might want @code{locale-definitions} to
12092 list only the locales that are actually used, as in:
12095 (list (locale-definition
12096 (name "ja_JP.eucjp") (source "ja_JP")
12097 (charset "EUC-JP")))
12101 The compiled locale definitions are available at
12102 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
12103 version, which is the default location where the GNU@tie{}libc provided
12104 by Guix looks for locale data. This can be overridden using the
12105 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
12106 @code{LOCPATH} and locale packages}).
12108 The @code{locale-definition} form is provided by the @code{(gnu system
12109 locale)} module. Details are given below.
12111 @deftp {Data Type} locale-definition
12112 This is the data type of a locale definition.
12117 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
12118 Reference Manual}, for more information on locale names.
12120 @item @code{source}
12121 The name of the source for that locale. This is typically the
12122 @code{@var{language}_@var{territory}} part of the locale name.
12124 @item @code{charset} (default: @code{"UTF-8"})
12125 The ``character set'' or ``code set'' for that locale,
12126 @uref{https://www.iana.org/assignments/character-sets, as defined by
12132 @defvr {Scheme Variable} %default-locale-definitions
12133 A list of commonly used UTF-8 locales, used as the default
12134 value of the @code{locale-definitions} field of @code{operating-system}
12137 @cindex locale name
12138 @cindex normalized codeset in locale names
12139 These locale definitions use the @dfn{normalized codeset} for the part
12140 that follows the dot in the name (@pxref{Using gettextized software,
12141 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
12142 instance it has @code{uk_UA.utf8} but @emph{not}, say,
12143 @code{uk_UA.UTF-8}.
12146 @subsection Locale Data Compatibility Considerations
12148 @cindex incompatibility, of locale data
12149 @code{operating-system} declarations provide a @code{locale-libcs} field
12150 to specify the GNU@tie{}libc packages that are used to compile locale
12151 declarations (@pxref{operating-system Reference}). ``Why would I
12152 care?'', you may ask. Well, it turns out that the binary format of
12153 locale data is occasionally incompatible from one libc version to
12156 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
12157 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
12158 For instance, a program linked against libc version 2.21 is unable to
12159 read locale data produced with libc 2.22; worse, that program
12160 @emph{aborts} instead of simply ignoring the incompatible locale
12161 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
12162 the incompatible locale data, which is already an improvement.}.
12163 Similarly, a program linked against libc 2.22 can read most, but not
12164 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
12165 data is incompatible); thus calls to @code{setlocale} may fail, but
12166 programs will not abort.
12168 The ``problem'' with Guix is that users have a lot of freedom: They can
12169 choose whether and when to upgrade software in their profiles, and might
12170 be using a libc version different from the one the system administrator
12171 used to build the system-wide locale data.
12173 Fortunately, unprivileged users can also install their own locale data
12174 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
12175 @code{GUIX_LOCPATH} and locale packages}).
12177 Still, it is best if the system-wide locale data at
12178 @file{/run/current-system/locale} is built for all the libc versions
12179 actually in use on the system, so that all the programs can access
12180 it---this is especially crucial on a multi-user system. To do that, the
12181 administrator can specify several libc packages in the
12182 @code{locale-libcs} field of @code{operating-system}:
12185 (use-package-modules base)
12189 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
12192 This example would lead to a system containing locale definitions for
12193 both libc 2.21 and the current version of libc in
12194 @file{/run/current-system/locale}.
12200 @cindex system services
12201 An important part of preparing an @code{operating-system} declaration is
12202 listing @dfn{system services} and their configuration (@pxref{Using the
12203 Configuration System}). System services are typically daemons launched
12204 when the system boots, or other actions needed at that time---e.g.,
12205 configuring network access.
12207 Guix has a broad definition of ``service'' (@pxref{Service
12208 Composition}), but many services are managed by the GNU@tie{}Shepherd
12209 (@pxref{Shepherd Services}). On a running system, the @command{herd}
12210 command allows you to list the available services, show their status,
12211 start and stop them, or do other specific operations (@pxref{Jump
12212 Start,,, shepherd, The GNU Shepherd Manual}). For example:
12218 The above command, run as @code{root}, lists the currently defined
12219 services. The @command{herd doc} command shows a synopsis of the given
12220 service and its associated actions:
12224 Run libc's name service cache daemon (nscd).
12226 # herd doc nscd action invalidate
12227 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
12230 The @command{start}, @command{stop}, and @command{restart} sub-commands
12231 have the effect you would expect. For instance, the commands below stop
12232 the nscd service and restart the Xorg display server:
12236 Service nscd has been stopped.
12237 # herd restart xorg-server
12238 Service xorg-server has been stopped.
12239 Service xorg-server has been started.
12242 The following sections document the available services, starting with
12243 the core services, that may be used in an @code{operating-system}
12247 * Base Services:: Essential system services.
12248 * Scheduled Job Execution:: The mcron service.
12249 * Log Rotation:: The rottlog service.
12250 * Networking Services:: Network setup, SSH daemon, etc.
12251 * X Window:: Graphical display.
12252 * Printing Services:: Local and remote printer support.
12253 * Desktop Services:: D-Bus and desktop services.
12254 * Sound Services:: ALSA and Pulseaudio services.
12255 * Database Services:: SQL databases, key-value stores, etc.
12256 * Mail Services:: IMAP, POP3, SMTP, and all that.
12257 * Messaging Services:: Messaging services.
12258 * Telephony Services:: Telephony services.
12259 * Monitoring Services:: Monitoring services.
12260 * Kerberos Services:: Kerberos services.
12261 * LDAP Services:: LDAP services.
12262 * Web Services:: Web servers.
12263 * Certificate Services:: TLS certificates via Let's Encrypt.
12264 * DNS Services:: DNS daemons.
12265 * VPN Services:: VPN daemons.
12266 * Network File System:: NFS related services.
12267 * Continuous Integration:: The Cuirass service.
12268 * Power Management Services:: Extending battery life.
12269 * Audio Services:: The MPD.
12270 * Virtualization Services:: Virtualization services.
12271 * Version Control Services:: Providing remote access to Git repositories.
12272 * Game Services:: Game servers.
12273 * PAM Mount Service:: Service to mount volumes when logging in.
12274 * Guix Services:: Services relating specifically to Guix.
12275 * Linux Services:: Services tied to the Linux kernel.
12276 * Miscellaneous Services:: Other services.
12279 @node Base Services
12280 @subsection Base Services
12282 The @code{(gnu services base)} module provides definitions for the basic
12283 services that one expects from the system. The services exported by
12284 this module are listed below.
12286 @defvr {Scheme Variable} %base-services
12287 This variable contains a list of basic services (@pxref{Service Types
12288 and Services}, for more information on service objects) one would
12289 expect from the system: a login service (mingetty) on each tty, syslogd,
12290 the libc name service cache daemon (nscd), the udev device manager, and
12293 This is the default value of the @code{services} field of
12294 @code{operating-system} declarations. Usually, when customizing a
12295 system, you will want to append services to @code{%base-services}, like
12299 (append (list (service avahi-service-type)
12300 (service openssh-service-type))
12305 @defvr {Scheme Variable} special-files-service-type
12306 This is the service that sets up ``special files'' such as
12307 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
12309 The value associated with @code{special-files-service-type} services
12310 must be a list of tuples where the first element is the ``special file''
12311 and the second element is its target. By default it is:
12313 @cindex @file{/bin/sh}
12314 @cindex @file{sh}, in @file{/bin}
12316 `(("/bin/sh" ,(file-append bash "/bin/sh")))
12319 @cindex @file{/usr/bin/env}
12320 @cindex @file{env}, in @file{/usr/bin}
12321 If you want to add, say, @code{/usr/bin/env} to your system, you can
12325 `(("/bin/sh" ,(file-append bash "/bin/sh"))
12326 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
12329 Since this is part of @code{%base-services}, you can use
12330 @code{modify-services} to customize the set of special files
12331 (@pxref{Service Reference, @code{modify-services}}). But the simple way
12332 to add a special file is @i{via} the @code{extra-special-file} procedure
12336 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
12337 Use @var{target} as the ``special file'' @var{file}.
12339 For example, adding the following lines to the @code{services} field of
12340 your operating system declaration leads to a @file{/usr/bin/env}
12344 (extra-special-file "/usr/bin/env"
12345 (file-append coreutils "/bin/env"))
12349 @deffn {Scheme Procedure} host-name-service @var{name}
12350 Return a service that sets the host name to @var{name}.
12353 @defvr {Scheme Variable} console-font-service-type
12354 Install the given fonts on the specified ttys (fonts are per
12355 virtual console on the kernel Linux). The value of this service is a list of
12356 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
12357 package or any valid argument to @command{setfont}, as in this example:
12360 `(("tty1" . "LatGrkCyr-8x16")
12361 ("tty2" . ,(file-append
12363 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
12364 ("tty3" . ,(file-append
12366 "/share/consolefonts/ter-132n"))) ; for HDPI
12370 @deffn {Scheme Procedure} login-service @var{config}
12371 Return a service to run login according to @var{config}, a
12372 @code{<login-configuration>} object, which specifies the message of the day,
12373 among other things.
12376 @deftp {Data Type} login-configuration
12377 This is the data type representing the configuration of login.
12382 @cindex message of the day
12383 A file-like object containing the ``message of the day''.
12385 @item @code{allow-empty-passwords?} (default: @code{#t})
12386 Allow empty passwords by default so that first-time users can log in when
12387 the 'root' account has just been created.
12392 @deffn {Scheme Procedure} mingetty-service @var{config}
12393 Return a service to run mingetty according to @var{config}, a
12394 @code{<mingetty-configuration>} object, which specifies the tty to run, among
12398 @deftp {Data Type} mingetty-configuration
12399 This is the data type representing the configuration of Mingetty, which
12400 provides the default implementation of virtual console log-in.
12405 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
12407 @item @code{auto-login} (default: @code{#f})
12408 When true, this field must be a string denoting the user name under
12409 which the system automatically logs in. When it is @code{#f}, a
12410 user name and password must be entered to log in.
12412 @item @code{login-program} (default: @code{#f})
12413 This must be either @code{#f}, in which case the default log-in program
12414 is used (@command{login} from the Shadow tool suite), or a gexp denoting
12415 the name of the log-in program.
12417 @item @code{login-pause?} (default: @code{#f})
12418 When set to @code{#t} in conjunction with @var{auto-login}, the user
12419 will have to press a key before the log-in shell is launched.
12421 @item @code{mingetty} (default: @var{mingetty})
12422 The Mingetty package to use.
12427 @deffn {Scheme Procedure} agetty-service @var{config}
12428 Return a service to run agetty according to @var{config}, an
12429 @code{<agetty-configuration>} object, which specifies the tty to run,
12430 among other things.
12433 @deftp {Data Type} agetty-configuration
12434 This is the data type representing the configuration of agetty, which
12435 implements virtual and serial console log-in. See the @code{agetty(8)}
12436 man page for more information.
12441 The name of the console this agetty runs on, as a string---e.g.,
12442 @code{"ttyS0"}. This argument is optional, it will default to
12443 a reasonable default serial port used by the kernel Linux.
12445 For this, if there is a value for an option @code{agetty.tty} in the kernel
12446 command line, agetty will extract the device name of the serial port
12447 from it and use that.
12449 If not and if there is a value for an option @code{console} with a tty in
12450 the Linux command line, agetty will extract the device name of the
12451 serial port from it and use that.
12453 In both cases, agetty will leave the other serial device settings
12454 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
12457 @item @code{baud-rate} (default: @code{#f})
12458 A string containing a comma-separated list of one or more baud rates, in
12461 @item @code{term} (default: @code{#f})
12462 A string containing the value used for the @code{TERM} environment
12465 @item @code{eight-bits?} (default: @code{#f})
12466 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
12469 @item @code{auto-login} (default: @code{#f})
12470 When passed a login name, as a string, the specified user will be logged
12471 in automatically without prompting for their login name or password.
12473 @item @code{no-reset?} (default: @code{#f})
12474 When @code{#t}, don't reset terminal cflags (control modes).
12476 @item @code{host} (default: @code{#f})
12477 This accepts a string containing the ``login_host'', which will be written
12478 into the @file{/var/run/utmpx} file.
12480 @item @code{remote?} (default: @code{#f})
12481 When set to @code{#t} in conjunction with @var{host}, this will add an
12482 @code{-r} fakehost option to the command line of the login program
12483 specified in @var{login-program}.
12485 @item @code{flow-control?} (default: @code{#f})
12486 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
12488 @item @code{no-issue?} (default: @code{#f})
12489 When set to @code{#t}, the contents of the @file{/etc/issue} file will
12490 not be displayed before presenting the login prompt.
12492 @item @code{init-string} (default: @code{#f})
12493 This accepts a string that will be sent to the tty or modem before
12494 sending anything else. It can be used to initialize a modem.
12496 @item @code{no-clear?} (default: @code{#f})
12497 When set to @code{#t}, agetty will not clear the screen before showing
12500 @item @code{login-program} (default: (file-append shadow "/bin/login"))
12501 This must be either a gexp denoting the name of a log-in program, or
12502 unset, in which case the default value is the @command{login} from the
12505 @item @code{local-line} (default: @code{#f})
12506 Control the CLOCAL line flag. This accepts one of three symbols as
12507 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
12508 the default value chosen by agetty is @code{'auto}.
12510 @item @code{extract-baud?} (default: @code{#f})
12511 When set to @code{#t}, instruct agetty to try to extract the baud rate
12512 from the status messages produced by certain types of modems.
12514 @item @code{skip-login?} (default: @code{#f})
12515 When set to @code{#t}, do not prompt the user for a login name. This
12516 can be used with @var{login-program} field to use non-standard login
12519 @item @code{no-newline?} (default: @code{#f})
12520 When set to @code{#t}, do not print a newline before printing the
12521 @file{/etc/issue} file.
12523 @c Is this dangerous only when used with login-program, or always?
12524 @item @code{login-options} (default: @code{#f})
12525 This option accepts a string containing options that are passed to the
12526 login program. When used with the @var{login-program}, be aware that a
12527 malicious user could try to enter a login name containing embedded
12528 options that could be parsed by the login program.
12530 @item @code{login-pause} (default: @code{#f})
12531 When set to @code{#t}, wait for any key before showing the login prompt.
12532 This can be used in conjunction with @var{auto-login} to save memory by
12533 lazily spawning shells.
12535 @item @code{chroot} (default: @code{#f})
12536 Change root to the specified directory. This option accepts a directory
12539 @item @code{hangup?} (default: @code{#f})
12540 Use the Linux system call @code{vhangup} to do a virtual hangup of the
12541 specified terminal.
12543 @item @code{keep-baud?} (default: @code{#f})
12544 When set to @code{#t}, try to keep the existing baud rate. The baud
12545 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
12548 @item @code{timeout} (default: @code{#f})
12549 When set to an integer value, terminate if no user name could be read
12550 within @var{timeout} seconds.
12552 @item @code{detect-case?} (default: @code{#f})
12553 When set to @code{#t}, turn on support for detecting an uppercase-only
12554 terminal. This setting will detect a login name containing only
12555 uppercase letters as indicating an uppercase-only terminal and turn on
12556 some upper-to-lower case conversions. Note that this will not support
12557 Unicode characters.
12559 @item @code{wait-cr?} (default: @code{#f})
12560 When set to @code{#t}, wait for the user or modem to send a
12561 carriage-return or linefeed character before displaying
12562 @file{/etc/issue} or login prompt. This is typically used with the
12563 @var{init-string} option.
12565 @item @code{no-hints?} (default: @code{#f})
12566 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
12569 @item @code{no-hostname?} (default: @code{#f})
12570 By default, the hostname is printed. When this option is set to
12571 @code{#t}, no hostname will be shown at all.
12573 @item @code{long-hostname?} (default: @code{#f})
12574 By default, the hostname is only printed until the first dot. When this
12575 option is set to @code{#t}, the fully qualified hostname by
12576 @code{gethostname} or @code{getaddrinfo} is shown.
12578 @item @code{erase-characters} (default: @code{#f})
12579 This option accepts a string of additional characters that should be
12580 interpreted as backspace when the user types their login name.
12582 @item @code{kill-characters} (default: @code{#f})
12583 This option accepts a string that should be interpreted to mean ``ignore
12584 all previous characters'' (also called a ``kill'' character) when the user
12585 types their login name.
12587 @item @code{chdir} (default: @code{#f})
12588 This option accepts, as a string, a directory path that will be changed
12591 @item @code{delay} (default: @code{#f})
12592 This options accepts, as an integer, the number of seconds to sleep
12593 before opening the tty and displaying the login prompt.
12595 @item @code{nice} (default: @code{#f})
12596 This option accepts, as an integer, the nice value with which to run the
12597 @command{login} program.
12599 @item @code{extra-options} (default: @code{'()})
12600 This option provides an ``escape hatch'' for the user to provide arbitrary
12601 command-line arguments to @command{agetty} as a list of strings.
12606 @deffn {Scheme Procedure} kmscon-service-type @var{config}
12607 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
12608 according to @var{config}, a @code{<kmscon-configuration>} object, which
12609 specifies the tty to run, among other things.
12612 @deftp {Data Type} kmscon-configuration
12613 This is the data type representing the configuration of Kmscon, which
12614 implements virtual console log-in.
12618 @item @code{virtual-terminal}
12619 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
12621 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
12622 A gexp denoting the name of the log-in program. The default log-in program is
12623 @command{login} from the Shadow tool suite.
12625 @item @code{login-arguments} (default: @code{'("-p")})
12626 A list of arguments to pass to @command{login}.
12628 @item @code{auto-login} (default: @code{#f})
12629 When passed a login name, as a string, the specified user will be logged
12630 in automatically without prompting for their login name or password.
12632 @item @code{hardware-acceleration?} (default: #f)
12633 Whether to use hardware acceleration.
12635 @item @code{kmscon} (default: @var{kmscon})
12636 The Kmscon package to use.
12641 @cindex name service cache daemon
12643 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
12644 [#:name-services '()]
12645 Return a service that runs the libc name service cache daemon (nscd) with the
12646 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
12647 Service Switch}, for an example.
12649 For convenience, the Shepherd service for nscd provides the following actions:
12653 @cindex cache invalidation, nscd
12654 @cindex nscd, cache invalidation
12655 This invalidate the given cache. For instance, running:
12658 herd invalidate nscd hosts
12662 invalidates the host name lookup cache of nscd.
12665 Running @command{herd statistics nscd} displays information about nscd usage
12671 @defvr {Scheme Variable} %nscd-default-configuration
12672 This is the default @code{<nscd-configuration>} value (see below) used
12673 by @code{nscd-service}. It uses the caches defined by
12674 @code{%nscd-default-caches}; see below.
12677 @deftp {Data Type} nscd-configuration
12678 This is the data type representing the name service cache daemon (nscd)
12683 @item @code{name-services} (default: @code{'()})
12684 List of packages denoting @dfn{name services} that must be visible to
12685 the nscd---e.g., @code{(list @var{nss-mdns})}.
12687 @item @code{glibc} (default: @var{glibc})
12688 Package object denoting the GNU C Library providing the @command{nscd}
12691 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
12692 Name of the nscd log file. This is where debugging output goes when
12693 @code{debug-level} is strictly positive.
12695 @item @code{debug-level} (default: @code{0})
12696 Integer denoting the debugging levels. Higher numbers mean that more
12697 debugging output is logged.
12699 @item @code{caches} (default: @code{%nscd-default-caches})
12700 List of @code{<nscd-cache>} objects denoting things to be cached; see
12706 @deftp {Data Type} nscd-cache
12707 Data type representing a cache database of nscd and its parameters.
12711 @item @code{database}
12712 This is a symbol representing the name of the database to be cached.
12713 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
12714 @code{services}, which designate the corresponding NSS database
12715 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
12717 @item @code{positive-time-to-live}
12718 @itemx @code{negative-time-to-live} (default: @code{20})
12719 A number representing the number of seconds during which a positive or
12720 negative lookup result remains in cache.
12722 @item @code{check-files?} (default: @code{#t})
12723 Whether to check for updates of the files corresponding to
12726 For instance, when @var{database} is @code{hosts}, setting this flag
12727 instructs nscd to check for updates in @file{/etc/hosts} and to take
12730 @item @code{persistent?} (default: @code{#t})
12731 Whether the cache should be stored persistently on disk.
12733 @item @code{shared?} (default: @code{#t})
12734 Whether the cache should be shared among users.
12736 @item @code{max-database-size} (default: 32@tie{}MiB)
12737 Maximum size in bytes of the database cache.
12739 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
12740 @c settings, so leave them out.
12745 @defvr {Scheme Variable} %nscd-default-caches
12746 List of @code{<nscd-cache>} objects used by default by
12747 @code{nscd-configuration} (see above).
12749 It enables persistent and aggressive caching of service and host name
12750 lookups. The latter provides better host name lookup performance,
12751 resilience in the face of unreliable name servers, and also better
12752 privacy---often the result of host name lookups is in local cache, so
12753 external name servers do not even need to be queried.
12756 @anchor{syslog-configuration-type}
12759 @deftp {Data Type} syslog-configuration
12760 This data type represents the configuration of the syslog daemon.
12763 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12764 The syslog daemon to use.
12766 @item @code{config-file} (default: @code{%default-syslog.conf})
12767 The syslog configuration file to use.
12772 @anchor{syslog-service}
12774 @deffn {Scheme Procedure} syslog-service @var{config}
12775 Return a service that runs a syslog daemon according to @var{config}.
12777 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12778 information on the configuration file syntax.
12781 @defvr {Scheme Variable} guix-service-type
12782 This is the type of the service that runs the build daemon,
12783 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12784 @code{guix-configuration} record as described below.
12787 @anchor{guix-configuration-type}
12788 @deftp {Data Type} guix-configuration
12789 This data type represents the configuration of the Guix build daemon.
12790 @xref{Invoking guix-daemon}, for more information.
12793 @item @code{guix} (default: @var{guix})
12794 The Guix package to use.
12796 @item @code{build-group} (default: @code{"guixbuild"})
12797 Name of the group for build user accounts.
12799 @item @code{build-accounts} (default: @code{10})
12800 Number of build user accounts to create.
12802 @item @code{authorize-key?} (default: @code{#t})
12803 @cindex substitutes, authorization thereof
12804 Whether to authorize the substitute keys listed in
12805 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12806 (@pxref{Substitutes}).
12808 @vindex %default-authorized-guix-keys
12809 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12810 The list of authorized key files for archive imports, as a list of
12811 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12812 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12814 @item @code{use-substitutes?} (default: @code{#t})
12815 Whether to use substitutes.
12817 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12818 The list of URLs where to look for substitutes by default.
12820 @item @code{max-silent-time} (default: @code{0})
12821 @itemx @code{timeout} (default: @code{0})
12822 The number of seconds of silence and the number of seconds of activity,
12823 respectively, after which a build process times out. A value of zero
12824 disables the timeout.
12826 @item @code{log-compression} (default: @code{'bzip2})
12827 The type of compression used for build logs---one of @code{gzip},
12828 @code{bzip2}, or @code{none}.
12830 @item @code{extra-options} (default: @code{'()})
12831 List of extra command-line options for @command{guix-daemon}.
12833 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12834 File where @command{guix-daemon}'s standard output and standard error
12837 @cindex HTTP proxy, for @code{guix-daemon}
12838 @cindex proxy, for @code{guix-daemon} HTTP access
12839 @item @code{http-proxy} (default: @code{#f})
12840 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
12841 derivations and substitutes.
12843 It is also possible to change the daemon's proxy at run time through the
12844 @code{set-http-proxy} action, which restarts it:
12847 herd set-http-proxy guix-daemon http://localhost:8118
12850 To clear the proxy settings, run:
12853 herd set-http-proxy guix-daemon
12856 @item @code{tmpdir} (default: @code{#f})
12857 A directory path where the @command{guix-daemon} will perform builds.
12862 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12863 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12864 udev rules can be provided as a list of files through the @var{rules}
12865 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
12866 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
12867 creation of such rule files.
12869 The @command{herd rules udev} command, as root, returns the name of the
12870 directory containing all the active udev rules.
12873 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12874 Return a udev-rule file named @var{file-name} containing the rules
12875 defined by the @var{contents} literal.
12877 In the following example, a rule for a USB device is defined to be
12878 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12879 upon detecting a USB device with a given product identifier.
12882 (define %example-udev-rule
12884 "90-usb-thing.rules"
12885 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12886 "ATTR@{product@}==\"Example\", "
12887 "RUN+=\"/path/to/script\"")))
12891 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
12892 [#:groups @var{groups}]
12893 Return a service that extends @code{udev-service-type } with @var{rules}
12894 and @code{account-service-type} with @var{groups} as system groups.
12895 This works by creating a singleton service type
12896 @code{@var{name}-udev-rules}, of which the returned service is an
12899 Here we show how it can be used to extend @code{udev-service-type} with the
12900 previously defined rule @code{%example-udev-rule}.
12906 (cons (udev-rules-service 'usb-thing %example-udev-rule)
12907 %desktop-services)))
12911 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12912 Return a udev file named @var{file-name} containing the rules defined
12913 within @var{file}, a file-like object.
12915 The following example showcases how we can use an existing rule file.
12918 (use-modules (guix download) ;for url-fetch
12919 (guix packages) ;for origin
12922 (define %android-udev-rules
12924 "51-android-udev.rules"
12925 (let ((version "20170910"))
12928 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12929 "android-udev-rules/" version "/51-android.rules"))
12931 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12935 Additionally, Guix package definitions can be included in @var{rules} in
12936 order to extend the udev rules with the definitions found under their
12937 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12938 @var{file->udev-rule} example, we could have used the
12939 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12940 packages android)} module.
12942 The following example shows how to use the @var{android-udev-rules}
12943 package so that the Android tool @command{adb} can detect devices
12944 without root privileges. It also details how to create the
12945 @code{adbusers} group, which is required for the proper functioning of
12946 the rules defined within the @code{android-udev-rules} package. To
12947 create such a group, we must define it both as part of the
12948 @code{supplementary-groups} of our @code{user-account} declaration, as
12949 well as in the @var{groups} of the @code{udev-rules-service} procedure.
12952 (use-modules (gnu packages android) ;for android-udev-rules
12953 (gnu system shadow) ;for user-group
12958 (users (cons (user-account
12960 (supplementary-groups
12961 '("adbusers" ;for adb
12962 "wheel" "netdev" "audio" "video")))))
12965 (cons (udev-rules-service 'android android-udev-rules
12966 #:groups '("adbusers"))
12967 %desktop-services)))
12970 @defvr {Scheme Variable} urandom-seed-service-type
12971 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
12972 when rebooting. It also tries to seed @file{/dev/urandom} from
12973 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12977 @defvr {Scheme Variable} %random-seed-file
12978 This is the name of the file where some random bytes are saved by
12979 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12980 It defaults to @file{/var/lib/random-seed}.
12985 @defvr {Scheme Variable} gpm-service-type
12986 This is the type of the service that runs GPM, the @dfn{general-purpose
12987 mouse daemon}, which provides mouse support to the Linux console. GPM
12988 allows users to use the mouse in the console, notably to select, copy,
12991 The value for services of this type must be a @code{gpm-configuration}
12992 (see below). This service is not part of @code{%base-services}.
12995 @deftp {Data Type} gpm-configuration
12996 Data type representing the configuration of GPM.
12999 @item @code{options} (default: @code{%default-gpm-options})
13000 Command-line options passed to @command{gpm}. The default set of
13001 options instruct @command{gpm} to listen to mouse events on
13002 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
13005 @item @code{gpm} (default: @code{gpm})
13006 The GPM package to use.
13011 @anchor{guix-publish-service-type}
13012 @deffn {Scheme Variable} guix-publish-service-type
13013 This is the service type for @command{guix publish} (@pxref{Invoking
13014 guix publish}). Its value must be a @code{guix-publish-configuration}
13015 object, as described below.
13017 This assumes that @file{/etc/guix} already contains a signing key pair as
13018 created by @command{guix archive --generate-key} (@pxref{Invoking guix
13019 archive}). If that is not the case, the service will fail to start.
13022 @deftp {Data Type} guix-publish-configuration
13023 Data type representing the configuration of the @code{guix publish}
13027 @item @code{guix} (default: @code{guix})
13028 The Guix package to use.
13030 @item @code{port} (default: @code{80})
13031 The TCP port to listen for connections.
13033 @item @code{host} (default: @code{"localhost"})
13034 The host (and thus, network interface) to listen to. Use
13035 @code{"0.0.0.0"} to listen on all the network interfaces.
13037 @item @code{compression} (default: @code{'(("gzip" 3))})
13038 This is a list of compression method/level tuple used when compressing
13039 substitutes. For example, to compress all substitutes with @emph{both} lzip
13040 at level 7 and gzip at level 9, write:
13043 '(("lzip" 7) ("gzip" 9))
13046 Level 9 achieves the best compression ratio at the expense of increased CPU
13047 usage, whereas level 1 achieves fast compression.
13049 An empty list disables compression altogether.
13051 @item @code{nar-path} (default: @code{"nar"})
13052 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
13053 publish, @code{--nar-path}}, for details.
13055 @item @code{cache} (default: @code{#f})
13056 When it is @code{#f}, disable caching and instead generate archives on
13057 demand. Otherwise, this should be the name of a directory---e.g.,
13058 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
13059 archives and meta-data ready to be sent. @xref{Invoking guix publish,
13060 @option{--cache}}, for more information on the tradeoffs involved.
13062 @item @code{workers} (default: @code{#f})
13063 When it is an integer, this is the number of worker threads used for
13064 caching; when @code{#f}, the number of processors is used.
13065 @xref{Invoking guix publish, @option{--workers}}, for more information.
13067 @item @code{ttl} (default: @code{#f})
13068 When it is an integer, this denotes the @dfn{time-to-live} in seconds
13069 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
13070 for more information.
13074 @anchor{rngd-service}
13075 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
13076 [#:device "/dev/hwrng"]
13077 Return a service that runs the @command{rngd} program from @var{rng-tools}
13078 to add @var{device} to the kernel's entropy pool. The service will fail if
13079 @var{device} does not exist.
13082 @anchor{pam-limits-service}
13083 @cindex session limits
13088 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
13090 Return a service that installs a configuration file for the
13091 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
13092 @code{pam_limits} module}. The procedure optionally takes a list of
13093 @code{pam-limits-entry} values, which can be used to specify
13094 @code{ulimit} limits and nice priority limits to user sessions.
13096 The following limits definition sets two hard and soft limits for all
13097 login sessions of users in the @code{realtime} group:
13100 (pam-limits-service
13102 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
13103 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
13106 The first entry increases the maximum realtime priority for
13107 non-privileged processes; the second entry lifts any restriction of the
13108 maximum address space that can be locked in memory. These settings are
13109 commonly used for real-time audio systems.
13112 @node Scheduled Job Execution
13113 @subsection Scheduled Job Execution
13117 @cindex scheduling jobs
13118 The @code{(gnu services mcron)} module provides an interface to
13119 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
13120 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
13121 Unix @command{cron} daemon; the main difference is that it is
13122 implemented in Guile Scheme, which provides a lot of flexibility when
13123 specifying the scheduling of jobs and their actions.
13125 The example below defines an operating system that runs the
13126 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
13127 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
13128 well as the @command{mkid} command on behalf of an unprivileged user
13129 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
13130 gexps to introduce job definitions that are passed to mcron
13131 (@pxref{G-Expressions}).
13134 (use-modules (guix) (gnu) (gnu services mcron))
13135 (use-package-modules base idutils)
13137 (define updatedb-job
13138 ;; Run 'updatedb' at 3AM every day. Here we write the
13139 ;; job's action as a Scheme procedure.
13140 #~(job '(next-hour '(3))
13142 (execl (string-append #$findutils "/bin/updatedb")
13144 "--prunepaths=/tmp /var/tmp /gnu/store"))))
13146 (define garbage-collector-job
13147 ;; Collect garbage 5 minutes after midnight every day.
13148 ;; The job's action is a shell command.
13149 #~(job "5 0 * * *" ;Vixie cron syntax
13152 (define idutils-job
13153 ;; Update the index database as user "charlie" at 12:15PM
13154 ;; and 19:15PM. This runs from the user's home directory.
13155 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
13156 (string-append #$idutils "/bin/mkid src")
13161 (services (cons (service mcron-service-type
13162 (mcron-configuration
13163 (jobs (list garbage-collector-job
13169 For more complex jobs defined in Scheme where you need control over the top
13170 level, for instance to introduce a @code{use-modules} form, you can move your
13171 code to a separate program using the @code{program-file} procedure of the
13172 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
13176 (define %battery-alert-job
13177 ;; Beep when the battery percentage falls below %MIN-LEVEL.
13179 '(next-minute (range 0 60 1))
13181 "battery-alert.scm"
13182 (with-imported-modules (source-module-closure
13183 '((guix build utils)))
13185 (define %min-level 20)
13186 (use-modules (guix build utils)
13189 (ice-9 textual-ports)
13191 (setenv "LC_ALL" "C") ;ensure English output
13192 (and-let* ((input-pipe (open-pipe*
13194 #$(file-append acpi "/bin/acpi")))
13195 (output (get-string-all input-pipe))
13196 (m (string-match "Discharging, ([0-9]+)%" output))
13197 (level (string->number (match:substring m 1)))
13198 ((< level %min-level)))
13199 (format #t "warning: Battery level is low (~a%)~%" level)
13200 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
13203 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
13204 for more information on mcron job specifications. Below is the
13205 reference of the mcron service.
13207 On a running system, you can use the @code{schedule} action of the service to
13208 visualize the mcron jobs that will be executed next:
13211 # herd schedule mcron
13215 The example above lists the next five tasks that will be executed, but you can
13216 also specify the number of tasks to display:
13219 # herd schedule mcron 10
13222 @defvr {Scheme Variable} mcron-service-type
13223 This is the type of the @code{mcron} service, whose value is an
13224 @code{mcron-configuration} object.
13226 This service type can be the target of a service extension that provides
13227 it additional job specifications (@pxref{Service Composition}). In
13228 other words, it is possible to define services that provide additional
13232 @deftp {Data Type} mcron-configuration
13233 Data type representing the configuration of mcron.
13236 @item @code{mcron} (default: @var{mcron})
13237 The mcron package to use.
13240 This is a list of gexps (@pxref{G-Expressions}), where each gexp
13241 corresponds to an mcron job specification (@pxref{Syntax, mcron job
13242 specifications,, mcron, GNU@tie{}mcron}).
13248 @subsection Log Rotation
13251 @cindex log rotation
13253 Log files such as those found in @file{/var/log} tend to grow endlessly,
13254 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
13255 their contents in separate files, possibly compressed. The @code{(gnu
13256 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
13257 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
13259 This service is part of @code{%base-services}, and thus enabled by
13260 default, with the default settings, for commonly encountered log files.
13261 The example below shows how to extend it with an additional
13262 @dfn{rotation}, should you need to do that (usually, services that
13263 produce log files already take care of that):
13266 (use-modules (guix) (gnu))
13267 (use-service-modules admin)
13269 (define my-log-files
13270 ;; Log files that I want to rotate.
13271 '("/var/log/something.log" "/var/log/another.log"))
13275 (services (cons (simple-service 'rotate-my-stuff
13276 rottlog-service-type
13277 (list (log-rotation
13279 (files my-log-files))))
13283 @defvr {Scheme Variable} rottlog-service-type
13284 This is the type of the Rottlog service, whose value is a
13285 @code{rottlog-configuration} object.
13287 Other services can extend this one with new @code{log-rotation} objects
13288 (see below), thereby augmenting the set of files to be rotated.
13290 This service type can define mcron jobs (@pxref{Scheduled Job
13291 Execution}) to run the rottlog service.
13294 @deftp {Data Type} rottlog-configuration
13295 Data type representing the configuration of rottlog.
13298 @item @code{rottlog} (default: @code{rottlog})
13299 The Rottlog package to use.
13301 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
13302 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
13303 rottlog, GNU Rot[t]log Manual}).
13305 @item @code{rotations} (default: @code{%default-rotations})
13306 A list of @code{log-rotation} objects as defined below.
13309 This is a list of gexps where each gexp corresponds to an mcron job
13310 specification (@pxref{Scheduled Job Execution}).
13314 @deftp {Data Type} log-rotation
13315 Data type representing the rotation of a group of log files.
13317 Taking an example from the Rottlog manual (@pxref{Period Related File
13318 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
13324 (files '("/var/log/apache/*"))
13325 (options '("storedir apache-archives"
13331 The list of fields is as follows:
13334 @item @code{frequency} (default: @code{'weekly})
13335 The log rotation frequency, a symbol.
13338 The list of files or file glob patterns to rotate.
13340 @item @code{options} (default: @code{'()})
13341 The list of rottlog options for this rotation (@pxref{Configuration
13342 parameters,,, rottlog, GNU Rot[t]lg Manual}).
13344 @item @code{post-rotate} (default: @code{#f})
13345 Either @code{#f} or a gexp to execute once the rotation has completed.
13349 @defvr {Scheme Variable} %default-rotations
13350 Specifies weekly rotation of @code{%rotated-files} and of
13351 @file{/var/log/guix-daemon.log}.
13354 @defvr {Scheme Variable} %rotated-files
13355 The list of syslog-controlled files to be rotated. By default it is:
13356 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
13357 "/var/log/maillog")}.
13360 @node Networking Services
13361 @subsection Networking Services
13363 The @code{(gnu services networking)} module provides services to configure
13364 the network interface.
13366 @cindex DHCP, networking service
13367 @defvr {Scheme Variable} dhcp-client-service-type
13368 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
13369 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
13370 is the DHCP client package to use, @code{isc-dhcp} by default.
13373 @deffn {Scheme Procedure} dhcpd-service-type
13374 This type defines a service that runs a DHCP daemon. To create a
13375 service of this type, you must supply a @code{<dhcpd-configuration>}.
13379 (service dhcpd-service-type
13380 (dhcpd-configuration
13381 (config-file (local-file "my-dhcpd.conf"))
13382 (interfaces '("enp0s25"))))
13386 @deftp {Data Type} dhcpd-configuration
13388 @item @code{package} (default: @code{isc-dhcp})
13389 The package that provides the DHCP daemon. This package is expected to
13390 provide the daemon at @file{sbin/dhcpd} relative to its output
13391 directory. The default package is the
13392 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
13393 @item @code{config-file} (default: @code{#f})
13394 The configuration file to use. This is required. It will be passed to
13395 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
13396 object (@pxref{G-Expressions, file-like objects}). See @code{man
13397 dhcpd.conf} for details on the configuration file syntax.
13398 @item @code{version} (default: @code{"4"})
13399 The DHCP version to use. The ISC DHCP server supports the values ``4'',
13400 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
13401 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
13403 @item @code{run-directory} (default: @code{"/run/dhcpd"})
13404 The run directory to use. At service activation time, this directory
13405 will be created if it does not exist.
13406 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
13407 The PID file to use. This corresponds to the @code{-pf} option of
13408 @code{dhcpd}. See @code{man dhcpd} for details.
13409 @item @code{interfaces} (default: @code{'()})
13410 The names of the network interfaces on which dhcpd should listen for
13411 broadcasts. If this list is not empty, then its elements (which must be
13412 strings) will be appended to the @code{dhcpd} invocation when starting
13413 the daemon. It may not be necessary to explicitly specify any
13414 interfaces here; see @code{man dhcpd} for details.
13418 @defvr {Scheme Variable} static-networking-service-type
13419 This is the type for statically-configured network interfaces.
13420 @c TODO Document <static-networking> data structures.
13423 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
13424 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
13425 [#:requirement @code{'(udev)}]
13426 Return a service that starts @var{interface} with address @var{ip}. If
13427 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
13428 it must be a string specifying the default network gateway. @var{requirement}
13429 can be used to declare a dependency on another service before configuring the
13432 This procedure can be called several times, one for each network
13433 interface of interest. Behind the scenes what it does is extend
13434 @code{static-networking-service-type} with additional network interfaces
13440 (static-networking-service "eno1" "192.168.1.82"
13441 #:gateway "192.168.1.2"
13442 #:name-servers '("192.168.1.2"))
13449 @cindex network management
13450 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
13451 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
13452 management daemon that aims to simplify wired and wireless networking.
13454 This service adds the @var{wicd} package to the global profile, providing
13455 several commands to interact with the daemon and configure networking:
13456 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
13457 and @command{wicd-curses} user interfaces.
13460 @cindex ModemManager
13462 @defvr {Scheme Variable} modem-manager-service-type
13463 This is the service type for the
13464 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
13465 service. The value for this service type is a
13466 @code{modem-manager-configuration} record.
13468 This service is part of @code{%desktop-services} (@pxref{Desktop
13472 @deftp {Data Type} modem-manager-configuration
13473 Data type representing the configuration of ModemManager.
13476 @item @code{modem-manager} (default: @code{modem-manager})
13477 The ModemManager package to use.
13482 @cindex USB_ModeSwitch
13483 @cindex Modeswitching
13485 @defvr {Scheme Variable} usb-modeswitch-service-type
13486 This is the service type for the
13487 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
13488 value for this service type is a @code{usb-modeswitch-configuration} record.
13490 When plugged in, some USB modems (and other USB devices) initially present
13491 themselves as a read-only storage medium and not as a modem. They need to be
13492 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
13493 installs udev rules to automatically modeswitch these devices when they are
13496 This service is part of @code{%desktop-services} (@pxref{Desktop
13500 @deftp {Data Type} usb-modeswitch-configuration
13501 Data type representing the configuration of USB_ModeSwitch.
13504 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
13505 The USB_ModeSwitch package providing the binaries for modeswitching.
13507 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
13508 The package providing the device data and udev rules file used by
13511 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
13512 Which config file to use for the USB_ModeSwitch dispatcher. By default the
13513 config file shipped with USB_ModeSwitch is used which disables logging to
13514 @file{/var/log} among other default settings. If set to @code{#f}, no config
13520 @cindex NetworkManager
13522 @defvr {Scheme Variable} network-manager-service-type
13523 This is the service type for the
13524 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
13525 service. The value for this service type is a
13526 @code{network-manager-configuration} record.
13528 This service is part of @code{%desktop-services} (@pxref{Desktop
13532 @deftp {Data Type} network-manager-configuration
13533 Data type representing the configuration of NetworkManager.
13536 @item @code{network-manager} (default: @code{network-manager})
13537 The NetworkManager package to use.
13539 @item @code{dns} (default: @code{"default"})
13540 Processing mode for DNS, which affects how NetworkManager uses the
13541 @code{resolv.conf} configuration file.
13545 NetworkManager will update @code{resolv.conf} to reflect the nameservers
13546 provided by currently active connections.
13549 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
13550 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
13551 then update @code{resolv.conf} to point to the local nameserver.
13553 With this setting, you can share your network connection. For example when
13554 you want to share your network connection to another laptop @i{via} an
13555 Ethernet cable, you can open @command{nm-connection-editor} and configure the
13556 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
13557 and reestablish the connection (or reboot).
13559 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
13560 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
13561 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
13562 browser on your host system, or connect to the VM @i{via} SSH
13563 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
13564 host-to-guest connection, run this command once:
13567 nmcli connection add type tun \
13568 connection.interface-name tap0 \
13569 tun.mode tap tun.owner $(id -u) \
13570 ipv4.method shared \
13571 ipv4.addresses 172.28.112.1/24
13574 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
13575 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
13576 @command{qemu-system-...}.
13579 NetworkManager will not modify @code{resolv.conf}.
13582 @item @code{vpn-plugins} (default: @code{'()})
13583 This is the list of available plugins for virtual private networks
13584 (VPNs). An example of this is the @code{network-manager-openvpn}
13585 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
13591 @deffn {Scheme Variable} connman-service-type
13592 This is the service type to run @url{https://01.org/connman,Connman},
13593 a network connection manager.
13595 Its value must be an
13596 @code{connman-configuration} record as in this example:
13599 (service connman-service-type
13600 (connman-configuration
13601 (disable-vpn? #t)))
13604 See below for details about @code{connman-configuration}.
13607 @deftp {Data Type} connman-configuration
13608 Data Type representing the configuration of connman.
13611 @item @code{connman} (default: @var{connman})
13612 The connman package to use.
13614 @item @code{disable-vpn?} (default: @code{#f})
13615 When true, disable connman's vpn plugin.
13619 @cindex WPA Supplicant
13620 @defvr {Scheme Variable} wpa-supplicant-service-type
13621 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
13622 supplicant}, an authentication daemon required to authenticate against
13623 encrypted WiFi or ethernet networks.
13626 @deftp {Data Type} wpa-supplicant-configuration
13627 Data type representing the configuration of WPA Supplicant.
13629 It takes the following parameters:
13632 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
13633 The WPA Supplicant package to use.
13635 @item @code{dbus?} (default: @code{#t})
13636 Whether to listen for requests on D-Bus.
13638 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
13639 Where to store the PID file.
13641 @item @code{interface} (default: @code{#f})
13642 If this is set, it must specify the name of a network interface that
13643 WPA supplicant will control.
13645 @item @code{config-file} (default: @code{#f})
13646 Optional configuration file to use.
13648 @item @code{extra-options} (default: @code{'()})
13649 List of additional command-line arguments to pass to the daemon.
13653 @cindex hostapd service, for Wi-Fi access points
13654 @cindex Wi-Fi access points, hostapd service
13655 @defvr {Scheme Variable} hostapd-service-type
13656 This is the service type to run the @uref{https://w1.fi/hostapd/,
13657 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
13658 authentication servers. Its associated value must be a
13659 @code{hostapd-configuration} as shown below:
13662 ;; Use wlan1 to run the access point for "My Network".
13663 (service hostapd-service-type
13664 (hostapd-configuration
13665 (interface "wlan1")
13666 (ssid "My Network")
13671 @deftp {Data Type} hostapd-configuration
13672 This data type represents the configuration of the hostapd service, with
13673 the following fields:
13676 @item @code{package} (default: @code{hostapd})
13677 The hostapd package to use.
13679 @item @code{interface} (default: @code{"wlan0"})
13680 The network interface to run the WiFi access point.
13683 The SSID (@dfn{service set identifier}), a string that identifies this
13686 @item @code{broadcast-ssid?} (default: @code{#t})
13687 Whether to broadcast this SSID.
13689 @item @code{channel} (default: @code{1})
13690 The WiFi channel to use.
13692 @item @code{driver} (default: @code{"nl80211"})
13693 The driver interface type. @code{"nl80211"} is used with all Linux
13694 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
13695 RADIUS server that does # not control any wireless/wired driver.
13697 @item @code{extra-settings} (default: @code{""})
13698 Extra settings to append as-is to the hostapd configuration file. See
13699 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
13700 configuration file reference.
13704 @defvr {Scheme Variable} simulated-wifi-service-type
13705 This is the type of a service to simulate WiFi networking, which can be
13706 useful in virtual machines for testing purposes. The service loads the
13708 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
13709 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
13710 network that can be seen on @code{wlan0}, by default.
13712 The service's value is a @code{hostapd-configuration} record.
13716 @defvr {Scheme Variable} iptables-service-type
13717 This is the service type to set up an iptables configuration. iptables is a
13718 packet filtering framework supported by the Linux kernel. This service
13719 supports configuring iptables for both IPv4 and IPv6. A simple example
13720 configuration rejecting all incoming connections except those to the ssh port
13724 (service iptables-service-type
13725 (iptables-configuration
13726 (ipv4-rules (plain-file "iptables.rules" "*filter
13730 -A INPUT -p tcp --dport 22 -j ACCEPT
13731 -A INPUT -j REJECT --reject-with icmp-port-unreachable
13734 (ipv6-rules (plain-file "ip6tables.rules" "*filter
13738 -A INPUT -p tcp --dport 22 -j ACCEPT
13739 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
13745 @deftp {Data Type} iptables-configuration
13746 The data type representing the configuration of iptables.
13749 @item @code{iptables} (default: @code{iptables})
13750 The iptables package that provides @code{iptables-restore} and
13751 @code{ip6tables-restore}.
13752 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
13753 The iptables rules to use. It will be passed to @code{iptables-restore}.
13754 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13756 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
13757 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
13758 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13764 @defvr {Scheme Variable} nftables-service-type
13765 This is the service type to set up a nftables configuration. nftables is a
13766 netfilter project that aims to replace the existing iptables, ip6tables,
13767 arptables and ebtables framework. It provides a new packet filtering
13768 framework, a new user-space utility @command{nft}, and a compatibility layer
13769 for iptables. This service comes with a default ruleset
13770 @code{%default-nftables-ruleset} that rejecting all incomming connections
13771 except those to the ssh port 22. To use it, simply write:
13774 (service nftables-service-type)
13778 @deftp {Data Type} nftables-configuration
13779 The data type representing the configuration of nftables.
13782 @item @code{package} (default: @code{nftables})
13783 The nftables package that provides @command{nft}.
13784 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
13785 The nftables ruleset to use. This may be any ``file-like'' object
13786 (@pxref{G-Expressions, file-like objects}).
13790 @cindex NTP (Network Time Protocol), service
13791 @cindex ntpd, service for the Network Time Protocol daemon
13792 @cindex real time clock
13793 @defvr {Scheme Variable} ntp-service-type
13794 This is the type of the service running the @uref{https://www.ntp.org,
13795 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
13796 system clock synchronized with that of the specified NTP servers.
13798 The value of this service is an @code{ntpd-configuration} object, as described
13802 @deftp {Data Type} ntp-configuration
13803 This is the data type for the NTP service configuration.
13806 @item @code{servers} (default: @code{%ntp-servers})
13807 This is the list of servers (@code{<ntp-server>} records) with which
13808 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
13811 @item @code{allow-large-adjustment?} (default: @code{#t})
13812 This determines whether @command{ntpd} is allowed to make an initial
13813 adjustment of more than 1,000 seconds.
13815 @item @code{ntp} (default: @code{ntp})
13816 The NTP package to use.
13820 @defvr {Scheme Variable} %ntp-servers
13821 List of host names used as the default NTP servers. These are servers of the
13822 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
13825 @deftp {Data Type} ntp-server
13826 The data type representing the configuration of a NTP server.
13829 @item @code{type} (default: @code{'server})
13830 The type of the NTP server, given as a symbol. One of @code{'pool},
13831 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
13833 @item @code{address}
13834 The address of the server, as a string.
13836 @item @code{options}
13837 NTPD options to use with that specific server, given as a list of option names
13838 and/or of option names and values tuples. The following example define a server
13839 to use with the options @option{iburst} and @option{prefer}, as well as
13840 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
13845 (address "some.ntp.server.org")
13846 (options `(iburst (version 3) (maxpoll 16) prefer))))
13852 @deffn {Scheme Procedure} openntpd-service-type
13853 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
13854 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
13855 clock synchronized with that of the given servers.
13859 openntpd-service-type
13860 (openntpd-configuration
13861 (listen-on '("127.0.0.1" "::1"))
13862 (sensor '("udcf0 correction 70000"))
13863 (constraint-from '("www.gnu.org"))
13864 (constraints-from '("https://www.google.com/"))
13865 (allow-large-adjustment? #t)))
13870 @defvr {Scheme Variable} %openntpd-servers
13871 This variable is a list of the server addresses defined in
13872 @code{%ntp-servers}.
13875 @deftp {Data Type} openntpd-configuration
13877 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
13878 The openntpd executable to use.
13879 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
13880 A list of local IP addresses or hostnames the ntpd daemon should listen on.
13881 @item @code{query-from} (default: @code{'()})
13882 A list of local IP address the ntpd daemon should use for outgoing queries.
13883 @item @code{sensor} (default: @code{'()})
13884 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
13885 will listen to each sensor that actually exists and ignore non-existent ones.
13886 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
13888 @item @code{server} (default: @code{'()})
13889 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
13890 @item @code{servers} (default: @code{%openntp-servers})
13891 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
13892 @item @code{constraint-from} (default: @code{'()})
13893 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
13894 This time information is not used for precision but acts as an authenticated
13895 constraint, thereby reducing the impact of unauthenticated NTP
13896 man-in-the-middle attacks.
13897 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
13899 @item @code{constraints-from} (default: @code{'()})
13900 As with constraint from, specify a list of URLs, IP addresses or hostnames of
13901 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
13902 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
13903 @item @code{allow-large-adjustment?} (default: @code{#f})
13904 Determines if @code{ntpd} is allowed to make an initial adjustment of more
13910 @deffn {Scheme variable} inetd-service-type
13911 This service runs the @command{inetd} (@pxref{inetd invocation,,,
13912 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
13913 connections on internet sockets, and lazily starts the specified server
13914 program when a connection is made on one of these sockets.
13916 The value of this service is an @code{inetd-configuration} object. The
13917 following example configures the @command{inetd} daemon to provide the
13918 built-in @command{echo} service, as well as an smtp service which
13919 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
13920 gateway @code{hostname}:
13925 (inetd-configuration
13929 (socket-type 'stream)
13936 (socket-type 'stream)
13940 (program (file-append openssh "/bin/ssh"))
13942 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13943 "-W" "smtp-server:25" "user@@hostname")))))))
13946 See below for more details about @code{inetd-configuration}.
13949 @deftp {Data Type} inetd-configuration
13950 Data type representing the configuration of @command{inetd}.
13953 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13954 The @command{inetd} executable to use.
13956 @item @code{entries} (default: @code{'()})
13957 A list of @command{inetd} service entries. Each entry should be created
13958 by the @code{inetd-entry} constructor.
13962 @deftp {Data Type} inetd-entry
13963 Data type representing an entry in the @command{inetd} configuration.
13964 Each entry corresponds to a socket where @command{inetd} will listen for
13968 @item @code{node} (default: @code{#f})
13969 Optional string, a comma-separated list of local addresses
13970 @command{inetd} should use when listening for this service.
13971 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13972 description of all options.
13974 A string, the name must correspond to an entry in @code{/etc/services}.
13975 @item @code{socket-type}
13976 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13978 @item @code{protocol}
13979 A string, must correspond to an entry in @code{/etc/protocols}.
13980 @item @code{wait?} (default: @code{#t})
13981 Whether @command{inetd} should wait for the server to exit before
13982 listening to new service requests.
13984 A string containing the user (and, optionally, group) name of the user
13985 as whom the server should run. The group name can be specified in a
13986 suffix, separated by a colon or period, i.e.@: @code{"user"},
13987 @code{"user:group"} or @code{"user.group"}.
13988 @item @code{program} (default: @code{"internal"})
13989 The server program which will serve the requests, or @code{"internal"}
13990 if @command{inetd} should use a built-in service.
13991 @item @code{arguments} (default: @code{'()})
13992 A list strings or file-like objects, which are the server program's
13993 arguments, starting with the zeroth argument, i.e.@: the name of the
13994 program itself. For @command{inetd}'s internal services, this entry
13995 must be @code{'()} or @code{'("internal")}.
13998 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13999 detailed discussion of each configuration field.
14003 @defvr {Scheme Variable} tor-service-type
14004 This is the type for a service that runs the @uref{https://torproject.org,
14005 Tor} anonymous networking daemon. The service is configured using a
14006 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
14007 @code{tor} unprivileged user, which is a member of the @code{tor} group.
14011 @deftp {Data Type} tor-configuration
14013 @item @code{tor} (default: @code{tor})
14014 The package that provides the Tor daemon. This package is expected to provide
14015 the daemon at @file{bin/tor} relative to its output directory. The default
14016 package is the @uref{https://www.torproject.org, Tor Project's}
14019 @item @code{config-file} (default: @code{(plain-file "empty" "")})
14020 The configuration file to use. It will be appended to a default configuration
14021 file, and the final configuration file will be passed to @code{tor} via its
14022 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
14023 file-like objects}). See @code{man tor} for details on the configuration file
14026 @item @code{hidden-services} (default: @code{'()})
14027 The list of @code{<hidden-service>} records to use. For any hidden service
14028 you include in this list, appropriate configuration to enable the hidden
14029 service will be automatically added to the default configuration file. You
14030 may conveniently create @code{<hidden-service>} records using the
14031 @code{tor-hidden-service} procedure described below.
14033 @item @code{socks-socket-type} (default: @code{'tcp})
14034 The default socket type that Tor should use for its SOCKS socket. This must
14035 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
14036 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
14037 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
14038 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
14041 If you want to customize the SOCKS socket in more detail, leave
14042 @code{socks-socket-type} at its default value of @code{'tcp} and use
14043 @code{config-file} to override the default by providing your own
14044 @code{SocksPort} option.
14048 @cindex hidden service
14049 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
14050 Define a new Tor @dfn{hidden service} called @var{name} and implementing
14051 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
14054 '((22 "127.0.0.1:22")
14055 (80 "127.0.0.1:8080"))
14058 In this example, port 22 of the hidden service is mapped to local port 22, and
14059 port 80 is mapped to local port 8080.
14061 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
14062 the @file{hostname} file contains the @code{.onion} host name for the hidden
14065 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
14066 project's documentation} for more information.
14069 The @code{(gnu services rsync)} module provides the following services:
14071 You might want an rsync daemon if you have files that you want available
14072 so anyone (or just yourself) can download existing files or upload new
14075 @deffn {Scheme Variable} rsync-service-type
14076 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
14077 The value for this service type is a
14078 @command{rsync-configuration} record as in this example:
14081 (service rsync-service-type)
14084 See below for details about @code{rsync-configuration}.
14087 @deftp {Data Type} rsync-configuration
14088 Data type representing the configuration for @code{rsync-service}.
14091 @item @code{package} (default: @var{rsync})
14092 @code{rsync} package to use.
14094 @item @code{port-number} (default: @code{873})
14095 TCP port on which @command{rsync} listens for incoming connections. If port
14096 is less than @code{1024} @command{rsync} needs to be started as the
14097 @code{root} user and group.
14099 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
14100 Name of the file where @command{rsync} writes its PID.
14102 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
14103 Name of the file where @command{rsync} writes its lock file.
14105 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
14106 Name of the file where @command{rsync} writes its log file.
14108 @item @code{use-chroot?} (default: @var{#t})
14109 Whether to use chroot for @command{rsync} shared directory.
14111 @item @code{share-path} (default: @file{/srv/rsync})
14112 Location of the @command{rsync} shared directory.
14114 @item @code{share-comment} (default: @code{"Rsync share"})
14115 Comment of the @command{rsync} shared directory.
14117 @item @code{read-only?} (default: @var{#f})
14118 Read-write permissions to shared directory.
14120 @item @code{timeout} (default: @code{300})
14121 I/O timeout in seconds.
14123 @item @code{user} (default: @var{"root"})
14124 Owner of the @code{rsync} process.
14126 @item @code{group} (default: @var{"root"})
14127 Group of the @code{rsync} process.
14129 @item @code{uid} (default: @var{"rsyncd"})
14130 User name or user ID that file transfers to and from that module should take
14131 place as when the daemon was run as @code{root}.
14133 @item @code{gid} (default: @var{"rsyncd"})
14134 Group name or group ID that will be used when accessing the module.
14139 Furthermore, @code{(gnu services ssh)} provides the following services.
14143 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
14144 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
14145 [#:allow-empty-passwords? #f] [#:root-login? #f] @
14146 [#:syslog-output? #t] [#:x11-forwarding? #t] @
14147 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
14148 [#:public-key-authentication? #t] [#:initialize? #t]
14149 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
14150 @var{host-key} must designate a file containing the host key, and readable
14153 When @var{daemonic?} is true, @command{lshd} will detach from the
14154 controlling terminal and log its output to syslogd, unless one sets
14155 @var{syslog-output?} to false. Obviously, it also makes lsh-service
14156 depend on existence of syslogd service. When @var{pid-file?} is true,
14157 @command{lshd} writes its PID to the file called @var{pid-file}.
14159 When @var{initialize?} is true, automatically create the seed and host key
14160 upon service activation if they do not exist yet. This may take long and
14161 require interaction.
14163 When @var{initialize?} is false, it is up to the user to initialize the
14164 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
14165 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
14166 basics,,, lsh, LSH Manual}).
14168 When @var{interfaces} is empty, lshd listens for connections on all the
14169 network interfaces; otherwise, @var{interfaces} must be a list of host names
14172 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
14173 passwords, and @var{root-login?} specifies whether to accept log-ins as
14176 The other options should be self-descriptive.
14181 @deffn {Scheme Variable} openssh-service-type
14182 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
14183 shell daemon, @command{sshd}. Its value must be an
14184 @code{openssh-configuration} record as in this example:
14187 (service openssh-service-type
14188 (openssh-configuration
14189 (x11-forwarding? #t)
14190 (permit-root-login 'without-password)
14192 `(("alice" ,(local-file "alice.pub"))
14193 ("bob" ,(local-file "bob.pub"))))))
14196 See below for details about @code{openssh-configuration}.
14198 This service can be extended with extra authorized keys, as in this
14202 (service-extension openssh-service-type
14203 (const `(("charlie"
14204 ,(local-file "charlie.pub")))))
14208 @deftp {Data Type} openssh-configuration
14209 This is the configuration record for OpenSSH's @command{sshd}.
14212 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
14213 Name of the file where @command{sshd} writes its PID.
14215 @item @code{port-number} (default: @code{22})
14216 TCP port on which @command{sshd} listens for incoming connections.
14218 @item @code{permit-root-login} (default: @code{#f})
14219 This field determines whether and when to allow logins as root. If
14220 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
14221 If it's the symbol @code{'without-password}, then root logins are
14222 permitted but not with password-based authentication.
14224 @item @code{allow-empty-passwords?} (default: @code{#f})
14225 When true, users with empty passwords may log in. When false, they may
14228 @item @code{password-authentication?} (default: @code{#t})
14229 When true, users may log in with their password. When false, they have
14230 other authentication methods.
14232 @item @code{public-key-authentication?} (default: @code{#t})
14233 When true, users may log in using public key authentication. When
14234 false, users have to use other authentication method.
14236 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
14237 This is used only by protocol version 2.
14239 @item @code{x11-forwarding?} (default: @code{#f})
14240 When true, forwarding of X11 graphical client connections is
14241 enabled---in other words, @command{ssh} options @option{-X} and
14242 @option{-Y} will work.
14244 @item @code{allow-agent-forwarding?} (default: @code{#t})
14245 Whether to allow agent forwarding.
14247 @item @code{allow-tcp-forwarding?} (default: @code{#t})
14248 Whether to allow TCP forwarding.
14250 @item @code{gateway-ports?} (default: @code{#f})
14251 Whether to allow gateway ports.
14253 @item @code{challenge-response-authentication?} (default: @code{#f})
14254 Specifies whether challenge response authentication is allowed (e.g.@: via
14257 @item @code{use-pam?} (default: @code{#t})
14258 Enables the Pluggable Authentication Module interface. If set to
14259 @code{#t}, this will enable PAM authentication using
14260 @code{challenge-response-authentication?} and
14261 @code{password-authentication?}, in addition to PAM account and session
14262 module processing for all authentication types.
14264 Because PAM challenge response authentication usually serves an
14265 equivalent role to password authentication, you should disable either
14266 @code{challenge-response-authentication?} or
14267 @code{password-authentication?}.
14269 @item @code{print-last-log?} (default: @code{#t})
14270 Specifies whether @command{sshd} should print the date and time of the
14271 last user login when a user logs in interactively.
14273 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
14274 Configures external subsystems (e.g.@: file transfer daemon).
14276 This is a list of two-element lists, each of which containing the
14277 subsystem name and a command (with optional arguments) to execute upon
14280 The command @command{internal-sftp} implements an in-process SFTP
14281 server. Alternately, one can specify the @command{sftp-server} command:
14283 (service openssh-service-type
14284 (openssh-configuration
14286 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
14289 @item @code{accepted-environment} (default: @code{'()})
14290 List of strings describing which environment variables may be exported.
14292 Each string gets on its own line. See the @code{AcceptEnv} option in
14293 @code{man sshd_config}.
14295 This example allows ssh-clients to export the @code{COLORTERM} variable.
14296 It is set by terminal emulators, which support colors. You can use it in
14297 your shell's resource file to enable colors for the prompt and commands
14298 if this variable is set.
14301 (service openssh-service-type
14302 (openssh-configuration
14303 (accepted-environment '("COLORTERM"))))
14306 @item @code{authorized-keys} (default: @code{'()})
14307 @cindex authorized keys, SSH
14308 @cindex SSH authorized keys
14309 This is the list of authorized keys. Each element of the list is a user
14310 name followed by one or more file-like objects that represent SSH public
14314 (openssh-configuration
14316 `(("rekado" ,(local-file "rekado.pub"))
14317 ("chris" ,(local-file "chris.pub"))
14318 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
14322 registers the specified public keys for user accounts @code{rekado},
14323 @code{chris}, and @code{root}.
14325 Additional authorized keys can be specified @i{via}
14326 @code{service-extension}.
14328 Note that this does @emph{not} interfere with the use of
14329 @file{~/.ssh/authorized_keys}.
14331 @item @code{log-level} (default: @code{'info})
14332 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
14333 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
14334 page for @file{sshd_config} for the full list of level names.
14336 @item @code{extra-content} (default: @code{""})
14337 This field can be used to append arbitrary text to the configuration file. It
14338 is especially useful for elaborate configurations that cannot be expressed
14339 otherwise. This configuration, for example, would generally disable root
14340 logins, but permit them from one specific IP address:
14343 (openssh-configuration
14345 Match Address 192.168.0.1
14346 PermitRootLogin yes"))
14352 @deffn {Scheme Procedure} dropbear-service [@var{config}]
14353 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
14354 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
14357 For example, to specify a Dropbear service listening on port 1234, add
14358 this call to the operating system's @code{services} field:
14361 (dropbear-service (dropbear-configuration
14362 (port-number 1234)))
14366 @deftp {Data Type} dropbear-configuration
14367 This data type represents the configuration of a Dropbear SSH daemon.
14370 @item @code{dropbear} (default: @var{dropbear})
14371 The Dropbear package to use.
14373 @item @code{port-number} (default: 22)
14374 The TCP port where the daemon waits for incoming connections.
14376 @item @code{syslog-output?} (default: @code{#t})
14377 Whether to enable syslog output.
14379 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
14380 File name of the daemon's PID file.
14382 @item @code{root-login?} (default: @code{#f})
14383 Whether to allow @code{root} logins.
14385 @item @code{allow-empty-passwords?} (default: @code{#f})
14386 Whether to allow empty passwords.
14388 @item @code{password-authentication?} (default: @code{#t})
14389 Whether to enable password-based authentication.
14393 @defvr {Scheme Variable} %facebook-host-aliases
14394 This variable contains a string for use in @file{/etc/hosts}
14395 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
14396 line contains a entry that maps a known server name of the Facebook
14397 on-line service---e.g., @code{www.facebook.com}---to the local
14398 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
14400 This variable is typically used in the @code{hosts-file} field of an
14401 @code{operating-system} declaration (@pxref{operating-system Reference,
14402 @file{/etc/hosts}}):
14405 (use-modules (gnu) (guix))
14408 (host-name "mymachine")
14411 ;; Create a /etc/hosts file with aliases for "localhost"
14412 ;; and "mymachine", as well as for Facebook servers.
14413 (plain-file "hosts"
14414 (string-append (local-host-aliases host-name)
14415 %facebook-host-aliases))))
14418 This mechanism can prevent programs running locally, such as Web
14419 browsers, from accessing Facebook.
14422 The @code{(gnu services avahi)} provides the following definition.
14424 @defvr {Scheme Variable} avahi-service-type
14425 This is the service that runs @command{avahi-daemon}, a system-wide
14426 mDNS/DNS-SD responder that allows for service discovery and
14427 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
14428 Its value must be a @code{zero-configuration} record---see below.
14430 This service extends the name service cache daemon (nscd) so that it can
14431 resolve @code{.local} host names using
14432 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
14433 Service Switch}, for information on host name resolution.
14435 Additionally, add the @var{avahi} package to the system profile so that
14436 commands such as @command{avahi-browse} are directly usable.
14439 @deftp {Data Type} avahi-configuration
14440 Data type representation the configuration for Avahi.
14444 @item @code{host-name} (default: @code{#f})
14445 If different from @code{#f}, use that as the host name to
14446 publish for this machine; otherwise, use the machine's actual host name.
14448 @item @code{publish?} (default: @code{#t})
14449 When true, allow host names and services to be published (broadcast) over the
14452 @item @code{publish-workstation?} (default: @code{#t})
14453 When true, @command{avahi-daemon} publishes the machine's host name and IP
14454 address via mDNS on the local network. To view the host names published on
14455 your local network, you can run:
14458 avahi-browse _workstation._tcp
14461 @item @code{wide-area?} (default: @code{#f})
14462 When true, DNS-SD over unicast DNS is enabled.
14464 @item @code{ipv4?} (default: @code{#t})
14465 @itemx @code{ipv6?} (default: @code{#t})
14466 These fields determine whether to use IPv4/IPv6 sockets.
14468 @item @code{domains-to-browse} (default: @code{'()})
14469 This is a list of domains to browse.
14473 @deffn {Scheme Variable} openvswitch-service-type
14474 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
14475 service, whose value should be an @code{openvswitch-configuration}
14479 @deftp {Data Type} openvswitch-configuration
14480 Data type representing the configuration of Open vSwitch, a multilayer
14481 virtual switch which is designed to enable massive network automation
14482 through programmatic extension.
14485 @item @code{package} (default: @var{openvswitch})
14486 Package object of the Open vSwitch.
14491 @defvr {Scheme Variable} pagekite-service-type
14492 This is the service type for the @uref{https://pagekite.net, PageKite} service,
14493 a tunneling solution for making localhost servers publicly visible, even from
14494 behind restrictive firewalls or NAT without forwarded ports. The value for
14495 this service type is a @code{pagekite-configuration} record.
14497 Here's an example exposing the local HTTP and SSH daemons:
14500 (service pagekite-service-type
14501 (pagekite-configuration
14502 (kites '("http:@@kitename:localhost:80:@@kitesecret"
14503 "raw/22:@@kitename:localhost:22:@@kitesecret"))
14504 (extra-file "/etc/pagekite.rc")))
14508 @deftp {Data Type} pagekite-configuration
14509 Data type representing the configuration of PageKite.
14512 @item @code{package} (default: @var{pagekite})
14513 Package object of PageKite.
14515 @item @code{kitename} (default: @code{#f})
14516 PageKite name for authenticating to the frontend server.
14518 @item @code{kitesecret} (default: @code{#f})
14519 Shared secret for authenticating to the frontend server. You should probably
14520 put this inside @code{extra-file} instead.
14522 @item @code{frontend} (default: @code{#f})
14523 Connect to the named PageKite frontend server instead of the
14524 @uref{https://pagekite.net,,pagekite.net} service.
14526 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
14527 List of service kites to use. Exposes HTTP on port 80 by default. The format
14528 is @code{proto:kitename:host:port:secret}.
14530 @item @code{extra-file} (default: @code{#f})
14531 Extra configuration file to read, which you are expected to create manually.
14532 Use this to add additional options and manage shared secrets out-of-band.
14538 @subsection X Window
14541 @cindex X Window System
14542 @cindex login manager
14543 Support for the X Window graphical display system---specifically
14544 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
14545 there is no @code{xorg-service} procedure. Instead, the X server is
14546 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
14549 @cindex GNOME, login manager
14550 GDM of course allows users to log in into window managers and desktop
14551 environments other than GNOME; for those using GNOME, GDM is required for
14552 features such as automatic screen locking.
14554 @cindex window manager
14555 To use X11, you must install at least one @dfn{window manager}---for
14556 example the @code{windowmaker} or @code{openbox} packages---preferably
14557 by adding it to the @code{packages} field of your operating system
14558 definition (@pxref{operating-system Reference, system-wide packages}).
14560 @defvr {Scheme Variable} gdm-service-type
14561 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
14562 Desktop Manager} (GDM), a program that manages graphical display servers and
14563 handles graphical user logins. Its value must be a @code{gdm-configuration}
14566 @cindex session types (X11)
14567 @cindex X11 session types
14568 GDM looks for @dfn{session types} described by the @file{.desktop} files in
14569 @file{/run/current-system/profile/share/xsessions} and allows users to choose
14570 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
14571 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
14572 set of packages automatically makes them available at the log-in screen.
14574 In addition, @file{~/.xsession} files are honored. When available,
14575 @file{~/.xsession} must be an executable that starts a window manager
14576 and/or other X clients.
14579 @deftp {Data Type} gdm-configuration
14581 @item @code{auto-login?} (default: @code{#f})
14582 @itemx @code{default-user} (default: @code{#f})
14583 When @code{auto-login?} is false, GDM presents a log-in screen.
14585 When @code{auto-login?} is true, GDM logs in directly as
14586 @code{default-user}.
14588 @item @code{debug?} (default: @code{#f})
14589 When true, GDM writes debug messages to its log.
14591 @item @code{gnome-shell-assets} (default: ...)
14592 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
14594 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
14595 Configuration of the Xorg graphical server.
14597 @item @code{xsession} (default: @code{(xinitrc)})
14598 Script to run before starting a X session.
14600 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
14601 File name of the @code{dbus-daemon} executable.
14603 @item @code{gdm} (default: @code{gdm})
14604 The GDM package to use.
14608 @defvr {Scheme Variable} slim-service-type
14609 This is the type for the SLiM graphical login manager for X11.
14611 Like GDM, SLiM looks for session types described by @file{.desktop} files and
14612 allows users to choose a session from the log-in screen using @kbd{F1}. It
14613 also honors @file{~/.xsession} files.
14615 Unlike GDM, SLiM does not spawn the user session on a different VT after
14616 logging in, which means that you can only start one graphical session. If you
14617 want to be able to run multiple graphical sessions at the same time you have
14618 to add multiple SLiM services to your system services. The following example
14619 shows how to replace the default GDM service with two SLiM services on tty7
14623 (use-modules (gnu services)
14624 (gnu services desktop)
14625 (gnu services xorg)
14626 (srfi srfi-1)) ;for 'remove'
14630 (services (cons* (service slim-service-type (slim-configuration
14633 (service slim-service-type (slim-configuration
14636 (remove (lambda (service)
14637 (eq? (service-kind service) gdm-service-type))
14638 %desktop-services))))
14643 @deftp {Data Type} slim-configuration
14644 Data type representing the configuration of @code{slim-service-type}.
14647 @item @code{allow-empty-passwords?} (default: @code{#t})
14648 Whether to allow logins with empty passwords.
14650 @item @code{auto-login?} (default: @code{#f})
14651 @itemx @code{default-user} (default: @code{""})
14652 When @code{auto-login?} is false, SLiM presents a log-in screen.
14654 When @code{auto-login?} is true, SLiM logs in directly as
14655 @code{default-user}.
14657 @item @code{theme} (default: @code{%default-slim-theme})
14658 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
14659 The graphical theme to use and its name.
14661 @item @code{auto-login-session} (default: @code{#f})
14662 If true, this must be the name of the executable to start as the default
14663 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
14665 If false, a session described by one of the available @file{.desktop}
14666 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
14670 You must install at least one window manager in the system profile or in
14671 your user profile. Failing to do that, if @code{auto-login-session} is
14672 false, you will be unable to log in.
14675 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14676 Configuration of the Xorg graphical server.
14678 @item @code{display} (default @code{":0"})
14679 The display on which to start the Xorg graphical server.
14681 @item @code{vt} (default @code{"vt7"})
14682 The VT on which to start the Xorg graphical server.
14684 @item @code{xauth} (default: @code{xauth})
14685 The XAuth package to use.
14687 @item @code{shepherd} (default: @code{shepherd})
14688 The Shepherd package used when invoking @command{halt} and
14691 @item @code{sessreg} (default: @code{sessreg})
14692 The sessreg package used in order to register the session.
14694 @item @code{slim} (default: @code{slim})
14695 The SLiM package to use.
14699 @defvr {Scheme Variable} %default-theme
14700 @defvrx {Scheme Variable} %default-theme-name
14701 The default SLiM theme and its name.
14705 @deftp {Data Type} sddm-configuration
14706 This is the data type representing the SDDM service configuration.
14709 @item @code{display-server} (default: "x11")
14710 Select display server to use for the greeter. Valid values are
14711 @samp{"x11"} or @samp{"wayland"}.
14713 @item @code{numlock} (default: "on")
14714 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
14716 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
14717 Command to run when halting.
14719 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
14720 Command to run when rebooting.
14722 @item @code{theme} (default "maldives")
14723 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
14724 @samp{"maldives"} or @samp{"maya"}.
14726 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
14727 Directory to look for themes.
14729 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
14730 Directory to look for faces.
14732 @item @code{default-path} (default "/run/current-system/profile/bin")
14733 Default PATH to use.
14735 @item @code{minimum-uid} (default: 1000)
14736 Minimum UID displayed in SDDM and allowed for log-in.
14738 @item @code{maximum-uid} (default: 2000)
14739 Maximum UID to display in SDDM.
14741 @item @code{remember-last-user?} (default #t)
14742 Remember last user.
14744 @item @code{remember-last-session?} (default #t)
14745 Remember last session.
14747 @item @code{hide-users} (default "")
14748 Usernames to hide from SDDM greeter.
14750 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
14751 Users with shells listed will be hidden from the SDDM greeter.
14753 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
14754 Script to run before starting a wayland session.
14756 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
14757 Directory to look for desktop files starting wayland sessions.
14759 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14760 Configuration of the Xorg graphical server.
14762 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
14765 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
14768 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
14769 Script to run after starting xorg-server.
14771 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
14772 Script to run before stopping xorg-server.
14774 @item @code{xsession-command} (default: @code{xinitrc})
14775 Script to run before starting a X session.
14777 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
14778 Directory to look for desktop files starting X sessions.
14780 @item @code{minimum-vt} (default: 7)
14783 @item @code{auto-login-user} (default "")
14784 User to use for auto-login.
14786 @item @code{auto-login-session} (default "")
14787 Desktop file to use for auto-login.
14789 @item @code{relogin?} (default #f)
14790 Relogin after logout.
14795 @cindex login manager
14797 @defvr {Scheme Variable} sddm-service-type
14798 This is the type of the service to run the
14799 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
14800 must be a @code{sddm-configuration} record (see below).
14802 Here's an example use:
14805 (service sddm-service-type
14806 (sddm-configuration
14807 (auto-login-user "alice")
14808 (auto-login-session "xfce.desktop")))
14812 @deftp {Data Type} sddm-configuration
14813 This data type represents the configuration of the SDDM login manager.
14814 The available fields are:
14817 @item @code{sddm} (default: @code{sddm})
14818 The SDDM package to use.
14820 @item @code{display-server} (default: @code{"x11"})
14821 This must be either @code{"x11"} or @code{"wayland"}.
14823 @c FIXME: Add more fields.
14825 @item @code{auto-login-user} (default: @code{""})
14826 If non-empty, this is the user account under which to log in
14829 @item @code{auto-login-session} (default: @code{""})
14830 If non-empty, this is the @file{.desktop} file name to use as the
14831 auto-login session.
14835 @cindex Xorg, configuration
14836 @deftp {Data Type} xorg-configuration
14837 This data type represents the configuration of the Xorg graphical display
14838 server. Note that there is not Xorg service; instead, the X server is started
14839 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
14840 of these display managers aggregates an @code{xorg-configuration} record.
14843 @item @code{modules} (default: @code{%default-xorg-modules})
14844 This is a list of @dfn{module packages} loaded by the Xorg
14845 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
14847 @item @code{fonts} (default: @code{%default-xorg-fonts})
14848 This is a list of font directories to add to the server's @dfn{font path}.
14850 @item @code{drivers} (default: @code{'()})
14851 This must be either the empty list, in which case Xorg chooses a graphics
14852 driver automatically, or a list of driver names that will be tried in this
14853 order---e.g., @code{("modesetting" "vesa")}.
14855 @item @code{resolutions} (default: @code{'()})
14856 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
14857 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
14860 @cindex keyboard layout, for Xorg
14861 @cindex keymap, for Xorg
14862 @item @code{keyboard-layout} (default: @code{#f})
14863 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
14864 English (``qwerty'') for a 105-key PC keyboard.
14866 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
14867 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
14868 information on how to specify the keyboard layout.
14870 @item @code{extra-config} (default: @code{'()})
14871 This is a list of strings or objects appended to the configuration file. It
14872 is used to pass extra text to be added verbatim to the configuration file.
14874 @item @code{server} (default: @code{xorg-server})
14875 This is the package providing the Xorg server.
14877 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
14878 This is the list of command-line arguments to pass to the X server. The
14879 default is @code{-nolisten tcp}.
14883 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
14884 [@var{login-manager-service-type}]
14885 Tell the log-in manager (of type @var{login-manager-service-type}) to use
14886 @var{config}, an @code{<xorg-configuration>} record.
14888 Since the Xorg configuration is embedded in the log-in manager's
14889 configuration---e.g., @code{gdm-configuration}---this procedure provides a
14890 shorthand to set the Xorg configuration.
14893 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
14894 Return a @code{startx} script in which the modules, fonts, etc. specified
14895 in @var{config}, are available. The result should be used in place of
14898 Usually the X server is started by a login manager.
14902 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
14903 Add @var{package}, a package for a screen locker or screen saver whose
14904 command is @var{program}, to the set of setuid programs and add a PAM entry
14905 for it. For example:
14908 (screen-locker-service xlockmore "xlock")
14911 makes the good ol' XlockMore usable.
14915 @node Printing Services
14916 @subsection Printing Services
14918 @cindex printer support with CUPS
14919 The @code{(gnu services cups)} module provides a Guix service definition
14920 for the CUPS printing service. To add printer support to a Guix
14921 system, add a @code{cups-service} to the operating system definition:
14923 @deffn {Scheme Variable} cups-service-type
14924 The service type for the CUPS print server. Its value should be a valid
14925 CUPS configuration (see below). To use the default settings, simply
14928 (service cups-service-type)
14932 The CUPS configuration controls the basic things about your CUPS
14933 installation: what interfaces it listens on, what to do if a print job
14934 fails, how much logging to do, and so on. To actually add a printer,
14935 you have to visit the @url{http://localhost:631} URL, or use a tool such
14936 as GNOME's printer configuration services. By default, configuring a
14937 CUPS service will generate a self-signed certificate if needed, for
14938 secure connections to the print server.
14940 Suppose you want to enable the Web interface of CUPS and also add
14941 support for Epson printers @i{via} the @code{escpr} package and for HP
14942 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
14943 like this (you need to use the @code{(gnu packages cups)} module):
14946 (service cups-service-type
14947 (cups-configuration
14948 (web-interface? #t)
14950 (list cups-filters escpr hplip-minimal))))
14953 Note: If you wish to use the Qt5 based GUI which comes with the hplip
14954 package then it is suggested that you install the @code{hplip} package,
14955 either in your OS configuration file or as your user.
14957 The available configuration parameters follow. Each parameter
14958 definition is preceded by its type; for example, @samp{string-list foo}
14959 indicates that the @code{foo} parameter should be specified as a list of
14960 strings. There is also a way to specify the configuration as a string,
14961 if you have an old @code{cupsd.conf} file that you want to port over
14962 from some other system; see the end for more details.
14964 @c The following documentation was initially generated by
14965 @c (generate-documentation) in (gnu services cups). Manually maintained
14966 @c documentation is better, so we shouldn't hesitate to edit below as
14967 @c needed. However if the change you want to make to this documentation
14968 @c can be done in an automated way, it's probably easier to change
14969 @c (generate-documentation) than to make it below and have to deal with
14970 @c the churn as CUPS updates.
14973 Available @code{cups-configuration} fields are:
14975 @deftypevr {@code{cups-configuration} parameter} package cups
14979 @deftypevr {@code{cups-configuration} parameter} package-list extensions
14980 Drivers and other extensions to the CUPS package.
14983 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
14984 Configuration of where to write logs, what directories to use for print
14985 spools, and related privileged configuration parameters.
14987 Available @code{files-configuration} fields are:
14989 @deftypevr {@code{files-configuration} parameter} log-location access-log
14990 Defines the access log filename. Specifying a blank filename disables
14991 access log generation. The value @code{stderr} causes log entries to be
14992 sent to the standard error file when the scheduler is running in the
14993 foreground, or to the system log daemon when run in the background. The
14994 value @code{syslog} causes log entries to be sent to the system log
14995 daemon. The server name may be included in filenames using the string
14996 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
14998 Defaults to @samp{"/var/log/cups/access_log"}.
15001 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
15002 Where CUPS should cache data.
15004 Defaults to @samp{"/var/cache/cups"}.
15007 @deftypevr {@code{files-configuration} parameter} string config-file-perm
15008 Specifies the permissions for all configuration files that the scheduler
15011 Note that the permissions for the printers.conf file are currently
15012 masked to only allow access from the scheduler user (typically root).
15013 This is done because printer device URIs sometimes contain sensitive
15014 authentication information that should not be generally known on the
15015 system. There is no way to disable this security feature.
15017 Defaults to @samp{"0640"}.
15020 @deftypevr {@code{files-configuration} parameter} log-location error-log
15021 Defines the error log filename. Specifying a blank filename disables
15022 error log generation. The value @code{stderr} causes log entries to be
15023 sent to the standard error file when the scheduler is running in the
15024 foreground, or to the system log daemon when run in the background. The
15025 value @code{syslog} causes log entries to be sent to the system log
15026 daemon. The server name may be included in filenames using the string
15027 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
15029 Defaults to @samp{"/var/log/cups/error_log"}.
15032 @deftypevr {@code{files-configuration} parameter} string fatal-errors
15033 Specifies which errors are fatal, causing the scheduler to exit. The
15038 No errors are fatal.
15041 All of the errors below are fatal.
15044 Browsing initialization errors are fatal, for example failed connections
15045 to the DNS-SD daemon.
15048 Configuration file syntax errors are fatal.
15051 Listen or Port errors are fatal, except for IPv6 failures on the
15052 loopback or @code{any} addresses.
15055 Log file creation or write errors are fatal.
15058 Bad startup file permissions are fatal, for example shared TLS
15059 certificate and key files with world-read permissions.
15062 Defaults to @samp{"all -browse"}.
15065 @deftypevr {@code{files-configuration} parameter} boolean file-device?
15066 Specifies whether the file pseudo-device can be used for new printer
15067 queues. The URI @uref{file:///dev/null} is always allowed.
15069 Defaults to @samp{#f}.
15072 @deftypevr {@code{files-configuration} parameter} string group
15073 Specifies the group name or ID that will be used when executing external
15076 Defaults to @samp{"lp"}.
15079 @deftypevr {@code{files-configuration} parameter} string log-file-perm
15080 Specifies the permissions for all log files that the scheduler writes.
15082 Defaults to @samp{"0644"}.
15085 @deftypevr {@code{files-configuration} parameter} log-location page-log
15086 Defines the page log filename. Specifying a blank filename disables
15087 page log generation. The value @code{stderr} causes log entries to be
15088 sent to the standard error file when the scheduler is running in the
15089 foreground, or to the system log daemon when run in the background. The
15090 value @code{syslog} causes log entries to be sent to the system log
15091 daemon. The server name may be included in filenames using the string
15092 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
15094 Defaults to @samp{"/var/log/cups/page_log"}.
15097 @deftypevr {@code{files-configuration} parameter} string remote-root
15098 Specifies the username that is associated with unauthenticated accesses
15099 by clients claiming to be the root user. The default is @code{remroot}.
15101 Defaults to @samp{"remroot"}.
15104 @deftypevr {@code{files-configuration} parameter} file-name request-root
15105 Specifies the directory that contains print jobs and other HTTP request
15108 Defaults to @samp{"/var/spool/cups"}.
15111 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
15112 Specifies the level of security sandboxing that is applied to print
15113 filters, backends, and other child processes of the scheduler; either
15114 @code{relaxed} or @code{strict}. This directive is currently only
15115 used/supported on macOS.
15117 Defaults to @samp{strict}.
15120 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
15121 Specifies the location of TLS certificates and private keys. CUPS will
15122 look for public and private keys in this directory: a @code{.crt} files
15123 for PEM-encoded certificates and corresponding @code{.key} files for
15124 PEM-encoded private keys.
15126 Defaults to @samp{"/etc/cups/ssl"}.
15129 @deftypevr {@code{files-configuration} parameter} file-name server-root
15130 Specifies the directory containing the server configuration files.
15132 Defaults to @samp{"/etc/cups"}.
15135 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
15136 Specifies whether the scheduler calls fsync(2) after writing
15137 configuration or state files.
15139 Defaults to @samp{#f}.
15142 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
15143 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
15146 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
15147 Specifies the directory where temporary files are stored.
15149 Defaults to @samp{"/var/spool/cups/tmp"}.
15152 @deftypevr {@code{files-configuration} parameter} string user
15153 Specifies the user name or ID that is used when running external
15156 Defaults to @samp{"lp"}.
15159 @deftypevr {@code{files-configuration} parameter} string set-env
15160 Set the specified environment variable to be passed to child processes.
15162 Defaults to @samp{"variable value"}.
15166 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
15167 Specifies the logging level for the AccessLog file. The @code{config}
15168 level logs when printers and classes are added, deleted, or modified and
15169 when configuration files are accessed or updated. The @code{actions}
15170 level logs when print jobs are submitted, held, released, modified, or
15171 canceled, and any of the conditions for @code{config}. The @code{all}
15172 level logs all requests.
15174 Defaults to @samp{actions}.
15177 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
15178 Specifies whether to purge job history data automatically when it is no
15179 longer required for quotas.
15181 Defaults to @samp{#f}.
15184 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
15185 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
15186 For example, @samp{"_cups" "_print"} will tell network clients that both
15187 CUPS sharing and IPP Everywhere are supported.
15189 Defaults to @samp{"_cups"}.
15192 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
15193 Specifies which protocols to use for local printer sharing.
15195 Defaults to @samp{dnssd}.
15198 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
15199 Specifies whether the CUPS web interface is advertised.
15201 Defaults to @samp{#f}.
15204 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
15205 Specifies whether shared printers are advertised.
15207 Defaults to @samp{#f}.
15210 @deftypevr {@code{cups-configuration} parameter} string classification
15211 Specifies the security classification of the server. Any valid banner
15212 name can be used, including @samp{"classified"}, @samp{"confidential"},
15213 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
15214 banner can be omitted to disable secure printing functions.
15216 Defaults to @samp{""}.
15219 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
15220 Specifies whether users may override the classification (cover page) of
15221 individual print jobs using the @code{job-sheets} option.
15223 Defaults to @samp{#f}.
15226 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
15227 Specifies the default type of authentication to use.
15229 Defaults to @samp{Basic}.
15232 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
15233 Specifies whether encryption will be used for authenticated requests.
15235 Defaults to @samp{Required}.
15238 @deftypevr {@code{cups-configuration} parameter} string default-language
15239 Specifies the default language to use for text and web content.
15241 Defaults to @samp{"en"}.
15244 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
15245 Specifies the default paper size for new print queues. @samp{"Auto"}
15246 uses a locale-specific default, while @samp{"None"} specifies there is
15247 no default paper size. Specific size names are typically
15248 @samp{"Letter"} or @samp{"A4"}.
15250 Defaults to @samp{"Auto"}.
15253 @deftypevr {@code{cups-configuration} parameter} string default-policy
15254 Specifies the default access policy to use.
15256 Defaults to @samp{"default"}.
15259 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
15260 Specifies whether local printers are shared by default.
15262 Defaults to @samp{#t}.
15265 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
15266 Specifies the delay for updating of configuration and state files, in
15267 seconds. A value of 0 causes the update to happen as soon as possible,
15268 typically within a few milliseconds.
15270 Defaults to @samp{30}.
15273 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
15274 Specifies what to do when an error occurs. Possible values are
15275 @code{abort-job}, which will discard the failed print job;
15276 @code{retry-job}, which will retry the job at a later time;
15277 @code{retry-current-job}, which retries the failed job immediately; and
15278 @code{stop-printer}, which stops the printer.
15280 Defaults to @samp{stop-printer}.
15283 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
15284 Specifies the maximum cost of filters that are run concurrently, which
15285 can be used to minimize disk, memory, and CPU resource problems. A
15286 limit of 0 disables filter limiting. An average print to a
15287 non-PostScript printer needs a filter limit of about 200. A PostScript
15288 printer needs about half that (100). Setting the limit below these
15289 thresholds will effectively limit the scheduler to printing a single job
15292 Defaults to @samp{0}.
15295 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
15296 Specifies the scheduling priority of filters that are run to print a
15297 job. The nice value ranges from 0, the highest priority, to 19, the
15300 Defaults to @samp{0}.
15303 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
15304 Specifies whether to do reverse lookups on connecting clients. The
15305 @code{double} setting causes @code{cupsd} to verify that the hostname
15306 resolved from the address matches one of the addresses returned for that
15307 hostname. Double lookups also prevent clients with unregistered
15308 addresses from connecting to your server. Only set this option to
15309 @code{#t} or @code{double} if absolutely required.
15311 Defaults to @samp{#f}.
15314 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
15315 Specifies the number of seconds to wait before killing the filters and
15316 backend associated with a canceled or held job.
15318 Defaults to @samp{30}.
15321 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
15322 Specifies the interval between retries of jobs in seconds. This is
15323 typically used for fax queues but can also be used with normal print
15324 queues whose error policy is @code{retry-job} or
15325 @code{retry-current-job}.
15327 Defaults to @samp{30}.
15330 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
15331 Specifies the number of retries that are done for jobs. This is
15332 typically used for fax queues but can also be used with normal print
15333 queues whose error policy is @code{retry-job} or
15334 @code{retry-current-job}.
15336 Defaults to @samp{5}.
15339 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
15340 Specifies whether to support HTTP keep-alive connections.
15342 Defaults to @samp{#t}.
15345 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
15346 Specifies how long an idle client connection remains open, in seconds.
15348 Defaults to @samp{30}.
15351 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
15352 Specifies the maximum size of print files, IPP requests, and HTML form
15353 data. A limit of 0 disables the limit check.
15355 Defaults to @samp{0}.
15358 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
15359 Listens on the specified interfaces for connections. Valid values are
15360 of the form @var{address}:@var{port}, where @var{address} is either an
15361 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
15362 indicate all addresses. Values can also be file names of local UNIX
15363 domain sockets. The Listen directive is similar to the Port directive
15364 but allows you to restrict access to specific interfaces or networks.
15367 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
15368 Specifies the number of pending connections that will be allowed. This
15369 normally only affects very busy servers that have reached the MaxClients
15370 limit, but can also be triggered by large numbers of simultaneous
15371 connections. When the limit is reached, the operating system will
15372 refuse additional connections until the scheduler can accept the pending
15375 Defaults to @samp{128}.
15378 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
15379 Specifies a set of additional access controls.
15381 Available @code{location-access-controls} fields are:
15383 @deftypevr {@code{location-access-controls} parameter} file-name path
15384 Specifies the URI path to which the access control applies.
15387 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
15388 Access controls for all access to this path, in the same format as the
15389 @code{access-controls} of @code{operation-access-control}.
15391 Defaults to @samp{()}.
15394 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
15395 Access controls for method-specific access to this path.
15397 Defaults to @samp{()}.
15399 Available @code{method-access-controls} fields are:
15401 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
15402 If @code{#t}, apply access controls to all methods except the listed
15403 methods. Otherwise apply to only the listed methods.
15405 Defaults to @samp{#f}.
15408 @deftypevr {@code{method-access-controls} parameter} method-list methods
15409 Methods to which this access control applies.
15411 Defaults to @samp{()}.
15414 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
15415 Access control directives, as a list of strings. Each string should be
15416 one directive, such as @samp{"Order allow,deny"}.
15418 Defaults to @samp{()}.
15423 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
15424 Specifies the number of debugging messages that are retained for logging
15425 if an error occurs in a print job. Debug messages are logged regardless
15426 of the LogLevel setting.
15428 Defaults to @samp{100}.
15431 @deftypevr {@code{cups-configuration} parameter} log-level log-level
15432 Specifies the level of logging for the ErrorLog file. The value
15433 @code{none} stops all logging while @code{debug2} logs everything.
15435 Defaults to @samp{info}.
15438 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
15439 Specifies the format of the date and time in the log files. The value
15440 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
15442 Defaults to @samp{standard}.
15445 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
15446 Specifies the maximum number of simultaneous clients that are allowed by
15449 Defaults to @samp{100}.
15452 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
15453 Specifies the maximum number of simultaneous clients that are allowed
15454 from a single address.
15456 Defaults to @samp{100}.
15459 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
15460 Specifies the maximum number of copies that a user can print of each
15463 Defaults to @samp{9999}.
15466 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
15467 Specifies the maximum time a job may remain in the @code{indefinite}
15468 hold state before it is canceled. A value of 0 disables cancellation of
15471 Defaults to @samp{0}.
15474 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
15475 Specifies the maximum number of simultaneous jobs that are allowed. Set
15476 to 0 to allow an unlimited number of jobs.
15478 Defaults to @samp{500}.
15481 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
15482 Specifies the maximum number of simultaneous jobs that are allowed per
15483 printer. A value of 0 allows up to MaxJobs jobs per printer.
15485 Defaults to @samp{0}.
15488 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
15489 Specifies the maximum number of simultaneous jobs that are allowed per
15490 user. A value of 0 allows up to MaxJobs jobs per user.
15492 Defaults to @samp{0}.
15495 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
15496 Specifies the maximum time a job may take to print before it is
15497 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
15499 Defaults to @samp{10800}.
15502 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
15503 Specifies the maximum size of the log files before they are rotated, in
15504 bytes. The value 0 disables log rotation.
15506 Defaults to @samp{1048576}.
15509 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
15510 Specifies the maximum amount of time to allow between files in a
15511 multiple file print job, in seconds.
15513 Defaults to @samp{300}.
15516 @deftypevr {@code{cups-configuration} parameter} string page-log-format
15517 Specifies the format of PageLog lines. Sequences beginning with percent
15518 (@samp{%}) characters are replaced with the corresponding information,
15519 while all other characters are copied literally. The following percent
15520 sequences are recognized:
15524 insert a single percent character
15527 insert the value of the specified IPP attribute
15530 insert the number of copies for the current page
15533 insert the current page number
15536 insert the current date and time in common log format
15542 insert the printer name
15545 insert the username
15548 A value of the empty string disables page logging. The string @code{%p
15549 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
15550 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
15553 Defaults to @samp{""}.
15556 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
15557 Passes the specified environment variable(s) to child processes; a list
15560 Defaults to @samp{()}.
15563 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
15564 Specifies named access control policies.
15566 Available @code{policy-configuration} fields are:
15568 @deftypevr {@code{policy-configuration} parameter} string name
15569 Name of the policy.
15572 @deftypevr {@code{policy-configuration} parameter} string job-private-access
15573 Specifies an access list for a job's private values. @code{@@ACL} maps
15574 to the printer's requesting-user-name-allowed or
15575 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15576 owner. @code{@@SYSTEM} maps to the groups listed for the
15577 @code{system-group} field of the @code{files-config} configuration,
15578 which is reified into the @code{cups-files.conf(5)} file. Other
15579 possible elements of the access list include specific user names, and
15580 @code{@@@var{group}} to indicate members of a specific group. The
15581 access list may also be simply @code{all} or @code{default}.
15583 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15586 @deftypevr {@code{policy-configuration} parameter} string job-private-values
15587 Specifies the list of job values to make private, or @code{all},
15588 @code{default}, or @code{none}.
15590 Defaults to @samp{"job-name job-originating-host-name
15591 job-originating-user-name phone"}.
15594 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
15595 Specifies an access list for a subscription's private values.
15596 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
15597 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15598 owner. @code{@@SYSTEM} maps to the groups listed for the
15599 @code{system-group} field of the @code{files-config} configuration,
15600 which is reified into the @code{cups-files.conf(5)} file. Other
15601 possible elements of the access list include specific user names, and
15602 @code{@@@var{group}} to indicate members of a specific group. The
15603 access list may also be simply @code{all} or @code{default}.
15605 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15608 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
15609 Specifies the list of job values to make private, or @code{all},
15610 @code{default}, or @code{none}.
15612 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
15613 notify-subscriber-user-name notify-user-data"}.
15616 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
15617 Access control by IPP operation.
15619 Defaults to @samp{()}.
15623 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
15624 Specifies whether job files (documents) are preserved after a job is
15625 printed. If a numeric value is specified, job files are preserved for
15626 the indicated number of seconds after printing. Otherwise a boolean
15627 value applies indefinitely.
15629 Defaults to @samp{86400}.
15632 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
15633 Specifies whether the job history is preserved after a job is printed.
15634 If a numeric value is specified, the job history is preserved for the
15635 indicated number of seconds after printing. If @code{#t}, the job
15636 history is preserved until the MaxJobs limit is reached.
15638 Defaults to @samp{#t}.
15641 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
15642 Specifies the amount of time to wait for job completion before
15643 restarting the scheduler.
15645 Defaults to @samp{30}.
15648 @deftypevr {@code{cups-configuration} parameter} string rip-cache
15649 Specifies the maximum amount of memory to use when converting documents
15650 into bitmaps for a printer.
15652 Defaults to @samp{"128m"}.
15655 @deftypevr {@code{cups-configuration} parameter} string server-admin
15656 Specifies the email address of the server administrator.
15658 Defaults to @samp{"root@@localhost.localdomain"}.
15661 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
15662 The ServerAlias directive is used for HTTP Host header validation when
15663 clients connect to the scheduler from external interfaces. Using the
15664 special name @code{*} can expose your system to known browser-based DNS
15665 rebinding attacks, even when accessing sites through a firewall. If the
15666 auto-discovery of alternate names does not work, we recommend listing
15667 each alternate name with a ServerAlias directive instead of using
15670 Defaults to @samp{*}.
15673 @deftypevr {@code{cups-configuration} parameter} string server-name
15674 Specifies the fully-qualified host name of the server.
15676 Defaults to @samp{"localhost"}.
15679 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
15680 Specifies what information is included in the Server header of HTTP
15681 responses. @code{None} disables the Server header. @code{ProductOnly}
15682 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
15683 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
15684 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
15685 the output of the @code{uname} command. @code{Full} reports @code{CUPS
15686 2.0.0 (@var{uname}) IPP/2.0}.
15688 Defaults to @samp{Minimal}.
15691 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
15692 Listens on the specified interfaces for encrypted connections. Valid
15693 values are of the form @var{address}:@var{port}, where @var{address} is
15694 either an IPv6 address enclosed in brackets, an IPv4 address, or
15695 @code{*} to indicate all addresses.
15697 Defaults to @samp{()}.
15700 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
15701 Sets encryption options. By default, CUPS only supports encryption
15702 using TLS v1.0 or higher using known secure cipher suites. Security is
15703 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
15704 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
15705 suites, which are required for some older clients. The @code{AllowSSL3} option
15706 enables SSL v3.0, which is required for some older clients that do not support
15707 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
15708 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
15709 protocol version to TLS v1.1.
15711 Defaults to @samp{()}.
15714 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
15715 Specifies whether the scheduler requires clients to strictly adhere to
15716 the IPP specifications.
15718 Defaults to @samp{#f}.
15721 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
15722 Specifies the HTTP request timeout, in seconds.
15724 Defaults to @samp{300}.
15728 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
15729 Specifies whether the web interface is enabled.
15731 Defaults to @samp{#f}.
15734 At this point you're probably thinking ``oh dear, Guix manual, I like
15735 you but you can stop already with the configuration options''. Indeed.
15736 However, one more point: it could be that you have an existing
15737 @code{cupsd.conf} that you want to use. In that case, you can pass an
15738 @code{opaque-cups-configuration} as the configuration of a
15739 @code{cups-service-type}.
15741 Available @code{opaque-cups-configuration} fields are:
15743 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
15747 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
15748 The contents of the @code{cupsd.conf}, as a string.
15751 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
15752 The contents of the @code{cups-files.conf} file, as a string.
15755 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
15756 strings of the same name, you could instantiate a CUPS service like
15760 (service cups-service-type
15761 (opaque-cups-configuration
15762 (cupsd.conf cupsd.conf)
15763 (cups-files.conf cups-files.conf)))
15767 @node Desktop Services
15768 @subsection Desktop Services
15770 The @code{(gnu services desktop)} module provides services that are
15771 usually useful in the context of a ``desktop'' setup---that is, on a
15772 machine running a graphical display server, possibly with graphical user
15773 interfaces, etc. It also defines services that provide specific desktop
15774 environments like GNOME, Xfce or MATE.
15776 To simplify things, the module defines a variable containing the set of
15777 services that users typically expect on a machine with a graphical
15778 environment and networking:
15780 @defvr {Scheme Variable} %desktop-services
15781 This is a list of services that builds upon @code{%base-services} and
15782 adds or adjusts services for a typical ``desktop'' setup.
15784 In particular, it adds a graphical login manager (@pxref{X Window,
15785 @code{gdm-service-type}}), screen lockers, a network management tool
15786 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
15787 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
15788 energy and color management services, the @code{elogind} login and seat
15789 manager, the Polkit privilege service, the GeoClue location service, the
15790 AccountsService daemon that allows authorized users change system passwords,
15791 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
15792 name service switch service configured to be able to use @code{nss-mdns}
15793 (@pxref{Name Service Switch, mDNS}).
15796 The @code{%desktop-services} variable can be used as the @code{services}
15797 field of an @code{operating-system} declaration (@pxref{operating-system
15798 Reference, @code{services}}).
15800 Additionally, the @code{gnome-desktop-service-type},
15801 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
15802 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
15803 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
15804 services like the backlight adjustment helpers and the power management
15805 utilities are added to the system, extending @code{polkit} and @code{dbus}
15806 appropriately, allowing GNOME to operate with elevated privileges on a
15807 limited number of special-purpose system interfaces. Additionally,
15808 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
15809 metapackage to the system profile. Likewise, adding the Xfce service
15810 not only adds the @code{xfce} metapackage to the system profile, but it
15811 also gives the Thunar file manager the ability to open a ``root-mode''
15812 file management window, if the user authenticates using the
15813 administrator's password via the standard polkit graphical interface.
15814 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
15815 appropriately, allowing MATE to operate with elevated privileges on a
15816 limited number of special-purpose system interfaces. Additionally,
15817 adding a service of type @code{mate-desktop-service-type} adds the MATE
15818 metapackage to the system profile. ``Adding Enlightenment'' means that
15819 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
15820 are set as setuid, allowing Enlightenment's screen locker and other
15821 functionality to work as expected.
15823 The desktop environments in Guix use the Xorg display server by
15824 default. If you'd like to use the newer display server protocol
15825 called Wayland, you need to use the @code{sddm-service} instead of
15826 GDM as the graphical login manager. You should then
15827 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
15828 also try starting GNOME on Wayland manually from a TTY with the
15829 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
15830 gnome-session``. Currently only GNOME has support for Wayland.
15832 @defvr {Scheme Variable} gnome-desktop-service-type
15833 This is the type of the service that adds the @uref{https://www.gnome.org,
15834 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
15835 object (see below.)
15837 This service adds the @code{gnome} package to the system profile, and extends
15838 polkit with the actions from @code{gnome-settings-daemon}.
15841 @deftp {Data Type} gnome-desktop-configuration
15842 Configuration record for the GNOME desktop environment.
15845 @item @code{gnome} (default: @code{gnome})
15846 The GNOME package to use.
15850 @defvr {Scheme Variable} xfce-desktop-service-type
15851 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
15852 desktop environment. Its value is an @code{xfce-desktop-configuration} object
15855 This service adds the @code{xfce} package to the system profile, and
15856 extends polkit with the ability for @code{thunar} to manipulate the file
15857 system as root from within a user session, after the user has authenticated
15858 with the administrator's password.
15861 @deftp {Data Type} xfce-desktop-configuration
15862 Configuration record for the Xfce desktop environment.
15865 @item @code{xfce} (default: @code{xfce})
15866 The Xfce package to use.
15870 @deffn {Scheme Variable} mate-desktop-service-type
15871 This is the type of the service that runs the @uref{https://mate-desktop.org/,
15872 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
15873 object (see below.)
15875 This service adds the @code{mate} package to the system
15876 profile, and extends polkit with the actions from
15877 @code{mate-settings-daemon}.
15880 @deftp {Data Type} mate-desktop-configuration
15881 Configuration record for the MATE desktop environment.
15884 @item @code{mate} (default: @code{mate})
15885 The MATE package to use.
15889 @deffn {Scheme Variable} enlightenment-desktop-service-type
15890 Return a service that adds the @code{enlightenment} package to the system
15891 profile, and extends dbus with actions from @code{efl}.
15894 @deftp {Data Type} enlightenment-desktop-service-configuration
15896 @item @code{enlightenment} (default: @code{enlightenment})
15897 The enlightenment package to use.
15901 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
15902 the default @code{%desktop-services} variable doesn't include any of
15903 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
15904 @code{%desktop-services} in the @code{services} field of your
15905 @code{operating-system}:
15908 (use-modules (gnu))
15909 (use-service-modules desktop)
15912 ;; cons* adds items to the list given as its last argument.
15913 (services (cons* (service gnome-desktop-service-type)
15914 (service xfce-desktop-service)
15915 %desktop-services))
15919 These desktop environments will then be available as options in the
15920 graphical login window.
15922 The actual service definitions included in @code{%desktop-services} and
15923 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
15924 are described below.
15926 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
15927 Return a service that runs the ``system bus'', using @var{dbus}, with
15928 support for @var{services}.
15930 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
15931 facility. Its system bus is used to allow system services to communicate
15932 and to be notified of system-wide events.
15934 @var{services} must be a list of packages that provide an
15935 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
15936 and policy files. For example, to allow avahi-daemon to use the system bus,
15937 @var{services} must be equal to @code{(list avahi)}.
15940 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
15941 Return a service that runs the @code{elogind} login and
15942 seat management daemon. @uref{https://github.com/elogind/elogind,
15943 Elogind} exposes a D-Bus interface that can be used to know which users
15944 are logged in, know what kind of sessions they have open, suspend the
15945 system, inhibit system suspend, reboot the system, and other tasks.
15947 Elogind handles most system-level power events for a computer, for
15948 example suspending the system when a lid is closed, or shutting it down
15949 when the power button is pressed.
15951 The @var{config} keyword argument specifies the configuration for
15952 elogind, and should be the result of an @code{(elogind-configuration
15953 (@var{parameter} @var{value})...)} invocation. Available parameters and
15954 their default values are:
15957 @item kill-user-processes?
15959 @item kill-only-users
15961 @item kill-exclude-users
15963 @item inhibit-delay-max-seconds
15965 @item handle-power-key
15967 @item handle-suspend-key
15969 @item handle-hibernate-key
15971 @item handle-lid-switch
15973 @item handle-lid-switch-docked
15975 @item power-key-ignore-inhibited?
15977 @item suspend-key-ignore-inhibited?
15979 @item hibernate-key-ignore-inhibited?
15981 @item lid-switch-ignore-inhibited?
15983 @item holdoff-timeout-seconds
15987 @item idle-action-seconds
15989 @item runtime-directory-size-percent
15991 @item runtime-directory-size
15995 @item suspend-state
15996 @code{("mem" "standby" "freeze")}
15999 @item hibernate-state
16001 @item hibernate-mode
16002 @code{("platform" "shutdown")}
16003 @item hybrid-sleep-state
16005 @item hybrid-sleep-mode
16006 @code{("suspend" "platform" "shutdown")}
16010 @deffn {Scheme Procedure} accountsservice-service @
16011 [#:accountsservice @var{accountsservice}]
16012 Return a service that runs AccountsService, a system service that can
16013 list available accounts, change their passwords, and so on.
16014 AccountsService integrates with PolicyKit to enable unprivileged users
16015 to acquire the capability to modify their system configuration.
16016 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
16017 accountsservice web site} for more information.
16019 The @var{accountsservice} keyword argument is the @code{accountsservice}
16020 package to expose as a service.
16023 @deffn {Scheme Procedure} polkit-service @
16024 [#:polkit @var{polkit}]
16025 Return a service that runs the
16026 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
16027 management service}, which allows system administrators to grant access to
16028 privileged operations in a structured way. By querying the Polkit service, a
16029 privileged system component can know when it should grant additional
16030 capabilities to ordinary users. For example, an ordinary user can be granted
16031 the capability to suspend the system if the user is logged in locally.
16034 @defvr {Scheme Variable} polkit-wheel-service
16035 Service that adds the @code{wheel} group as admins to the Polkit
16036 service. This makes it so that users in the @code{wheel} group are queried
16037 for their own passwords when performing administrative actions instead of
16038 @code{root}'s, similar to the behaviour used by @code{sudo}.
16041 @defvr {Scheme Variable} upower-service-type
16042 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
16043 system-wide monitor for power consumption and battery levels, with the given
16044 configuration settings.
16046 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
16047 notably used by GNOME.
16050 @deftp {Data Type} upower-configuration
16051 Data type representation the configuration for UPower.
16055 @item @code{upower} (default: @var{upower})
16056 Package to use for @code{upower}.
16058 @item @code{watts-up-pro?} (default: @code{#f})
16059 Enable the Watts Up Pro device.
16061 @item @code{poll-batteries?} (default: @code{#t})
16062 Enable polling the kernel for battery level changes.
16064 @item @code{ignore-lid?} (default: @code{#f})
16065 Ignore the lid state, this can be useful if it's incorrect on a device.
16067 @item @code{use-percentage-for-policy?} (default: @code{#f})
16068 Whether battery percentage based policy should be used. The default is to use
16069 the time left, change to @code{#t} to use the percentage.
16071 @item @code{percentage-low} (default: @code{10})
16072 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16073 at which the battery is considered low.
16075 @item @code{percentage-critical} (default: @code{3})
16076 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16077 at which the battery is considered critical.
16079 @item @code{percentage-action} (default: @code{2})
16080 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
16081 at which action will be taken.
16083 @item @code{time-low} (default: @code{1200})
16084 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16085 seconds at which the battery is considered low.
16087 @item @code{time-critical} (default: @code{300})
16088 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16089 seconds at which the battery is considered critical.
16091 @item @code{time-action} (default: @code{120})
16092 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16093 seconds at which action will be taken.
16095 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
16096 The action taken when @code{percentage-action} or @code{time-action} is
16097 reached (depending on the configuration of @code{use-percentage-for-policy?}).
16099 Possible values are:
16109 @code{'hybrid-sleep}.
16115 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
16116 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
16117 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
16118 notifications and ways to mount/unmount disks. Programs that talk to UDisks
16119 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
16122 @deffn {Scheme Variable} colord-service-type
16123 This is the type of the service that runs @command{colord}, a system
16124 service with a D-Bus
16125 interface to manage the color profiles of input and output devices such as
16126 screens and scanners. It is notably used by the GNOME Color Manager graphical
16127 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
16128 site} for more information.
16131 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
16132 Return a configuration allowing an application to access GeoClue
16133 location data. @var{name} is the Desktop ID of the application, without
16134 the @code{.desktop} part. If @var{allowed?} is true, the application
16135 will have access to location information by default. The boolean
16136 @var{system?} value indicates whether an application is a system component
16137 or not. Finally @var{users} is a list of UIDs of all users for which
16138 this application is allowed location info access. An empty users list
16139 means that all users are allowed.
16142 @cindex scanner access
16143 @deffn {Scheme Procedure} sane-service-type
16144 This service provides access to scanners @i{via}
16145 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
16149 @defvr {Scheme Variable} %standard-geoclue-applications
16150 The standard list of well-known GeoClue application configurations,
16151 granting authority to the GNOME date-and-time utility to ask for the
16152 current location in order to set the time zone, and allowing the
16153 IceCat and Epiphany web browsers to request location information.
16154 IceCat and Epiphany both query the user before allowing a web page to
16155 know the user's location.
16158 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
16159 [#:whitelist '()] @
16160 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
16161 [#:submit-data? #f]
16162 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
16163 [#:submission-nick "geoclue"] @
16164 [#:applications %standard-geoclue-applications]
16165 Return a service that runs the GeoClue location service. This service
16166 provides a D-Bus interface to allow applications to request access to a
16167 user's physical location, and optionally to add information to online
16168 location databases. See
16169 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
16170 web site} for more information.
16173 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
16174 [@w{#:auto-enable? #f}]
16175 Return a service that runs the @command{bluetoothd} daemon, which
16176 manages all the Bluetooth devices and provides a number of D-Bus
16177 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
16178 powered automatically at boot, which can be useful when using a
16179 bluetooth keyboard or mouse.
16181 Users need to be in the @code{lp} group to access the D-Bus service.
16184 @defvr {Scheme Variable} gnome-keyring-service-type
16185 This is the type of the service that adds the
16186 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
16187 value is a @code{gnome-keyring-configuration} object (see below.)
16189 This service adds the @code{gnome-keyring} package to the system profile
16190 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
16191 a user's login keyring when they log in or setting its password with passwd.
16194 @deftp {Data Type} gnome-keyring-configuration
16195 Configuration record for the GNOME Keyring service.
16198 @item @code{keyring} (default: @code{gnome-keyring})
16199 The GNOME keyring package to use.
16201 @item @code{pam-services}
16202 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
16203 services to extend, where @var{service} is the name of an existing
16204 service to extend and @var{kind} is one of @code{login} or
16207 If @code{login} is given, it adds an optional
16208 @code{pam_gnome_keyring.so} to the auth block without arguments and to
16209 the session block with @code{auto_start}. If @code{passwd} is given, it
16210 adds an optional @code{pam_gnome_keyring.so} to the password block
16213 By default, this field contains ``gdm-password'' with the value @code{login}
16214 and ``passwd'' is with the value @code{passwd}.
16219 @node Sound Services
16220 @subsection Sound Services
16222 @cindex sound support
16224 @cindex PulseAudio, sound support
16226 The @code{(gnu services sound)} module provides a service to configure the
16227 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
16228 preferred ALSA output driver.
16230 @deffn {Scheme Variable} alsa-service-type
16231 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
16232 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
16233 configuration file. The value for this type is a @command{alsa-configuration}
16234 record as in this example:
16237 (service alsa-service-type)
16240 See below for details about @code{alsa-configuration}.
16243 @deftp {Data Type} alsa-configuration
16244 Data type representing the configuration for @code{alsa-service}.
16247 @item @code{alsa-plugins} (default: @var{alsa-plugins})
16248 @code{alsa-plugins} package to use.
16250 @item @code{pulseaudio?} (default: @var{#t})
16251 Whether ALSA applications should transparently be made to use the
16252 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
16254 Using PulseAudio allows you to run several sound-producing applications
16255 at the same time and to individual control them @i{via}
16256 @command{pavucontrol}, among other things.
16258 @item @code{extra-options} (default: @var{""})
16259 String to append to the @file{/etc/asound.conf} file.
16264 Individual users who want to override the system configuration of ALSA can do
16265 it with the @file{~/.asoundrc} file:
16268 # In guix, we have to specify the absolute path for plugins.
16270 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
16273 # Routing ALSA to jack:
16274 # <http://jackaudio.org/faq/routing_alsa.html>.
16278 0 system:playback_1
16279 1 system:playback_2
16296 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
16299 @deffn {Scheme Variable} pulseaudio-service-type
16300 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
16301 sound server. It exists to allow system overrides of the default settings
16302 via @code{pulseaudio-configuration}, see below.
16305 This service overrides per-user configuration files. If you want
16306 PulseAudio to honor configuraton files in @file{~/.config/pulse} you
16307 have to unset the environment variables @code{PULSE_CONFIG} and
16308 @code{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
16312 This service on its own does not ensure, that the @code{pulseaudio} package
16313 exists on your machine. It merely adds configuration files for it, as
16314 detailed below. In the (admittedly unlikely) case, that you find yourself
16315 without a @code{pulseaudio} package, consider enabling it through the
16316 @code{alsa-service-type} above.
16320 @deftp {Data Type} pulseaudio-configuration
16321 Data type representing the configuration for @code{pulseaudio-service}.
16324 @item @var{client-conf} (default: @code{'()})
16325 List of settings to set in @file{client.conf}.
16326 Accepts a list of strings or a symbol-value pairs. A string will be
16327 inserted as-is with a newline added. A pair will be formatted as
16328 ``key = value'', again with a newline added.
16330 @item @var{daemon-conf} (default: @code{'((flat-volumes . no))})
16331 List of settings to set in @file{daemon.conf}, formatted just like
16334 @item @var{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
16335 Script file to use as as @file{default.pa}.
16337 @item @var{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
16338 Script file to use as as @file{system.pa}.
16342 @deffn {Scheme Variable} ladspa-service-type
16343 This service sets the @var{LADSPA_PATH} variable, so that programs, which
16344 respect it, e.g. PulseAudio, can load LADSPA plugins.
16346 The following example will setup the service to enable modules from the
16347 @code{swh-plugins} package:
16350 (service ladspa-service-type
16351 (ladspa-configuration (plugins (list swh-plugins))))
16354 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
16359 @node Database Services
16360 @subsection Database Services
16364 The @code{(gnu services databases)} module provides the following services.
16366 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
16367 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
16368 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
16369 Return a service that runs @var{postgresql}, the PostgreSQL database
16372 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
16373 creates a database cluster with @var{locale} as the default
16374 locale, stored in @var{data-directory}. It then listens on @var{port}.
16376 @cindex postgresql extension-packages
16377 Additional extensions are loaded from packages listed in
16378 @var{extension-packages}. Extensions are available at runtime. For instance,
16379 to create a geographic database using the @code{postgis} extension, a user can
16380 configure the postgresql-service as in this example:
16384 (use-package-modules databases geo)
16388 ;; postgresql is required to run `psql' but postgis is not required for
16389 ;; proper operation.
16390 (packages (cons* postgresql %base-packages))
16393 (postgresql-service #:extension-packages (list postgis))
16397 Then the extension becomes visible and you can initialise an empty geographic
16398 database in this way:
16402 > create database postgistest;
16403 > \connect postgistest;
16404 > create extension postgis;
16405 > create extension postgis_topology;
16408 There is no need to add this field for contrib extensions such as hstore or
16409 dblink as they are already loadable by postgresql. This field is only
16410 required to add extensions provided by other packages.
16413 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
16414 Return a service that runs @command{mysqld}, the MySQL or MariaDB
16417 The optional @var{config} argument specifies the configuration for
16418 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
16421 @deftp {Data Type} mysql-configuration
16422 Data type representing the configuration of @var{mysql-service}.
16425 @item @code{mysql} (default: @var{mariadb})
16426 Package object of the MySQL database server, can be either @var{mariadb}
16429 For MySQL, a temporary root password will be displayed at activation time.
16430 For MariaDB, the root password is empty.
16432 @item @code{port} (default: @code{3306})
16433 TCP port on which the database server listens for incoming connections.
16437 @defvr {Scheme Variable} memcached-service-type
16438 This is the service type for the @uref{https://memcached.org/,
16439 Memcached} service, which provides a distributed in memory cache. The
16440 value for the service type is a @code{memcached-configuration} object.
16444 (service memcached-service-type)
16447 @deftp {Data Type} memcached-configuration
16448 Data type representing the configuration of memcached.
16451 @item @code{memcached} (default: @code{memcached})
16452 The Memcached package to use.
16454 @item @code{interfaces} (default: @code{'("0.0.0.0")})
16455 Network interfaces on which to listen.
16457 @item @code{tcp-port} (default: @code{11211})
16458 Port on which to accept connections on,
16460 @item @code{udp-port} (default: @code{11211})
16461 Port on which to accept UDP connections on, a value of 0 will disable
16462 listening on a UDP socket.
16464 @item @code{additional-options} (default: @code{'()})
16465 Additional command line options to pass to @code{memcached}.
16469 @defvr {Scheme Variable} mongodb-service-type
16470 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
16471 The value for the service type is a @code{mongodb-configuration} object.
16475 (service mongodb-service-type)
16478 @deftp {Data Type} mongodb-configuration
16479 Data type representing the configuration of mongodb.
16482 @item @code{mongodb} (default: @code{mongodb})
16483 The MongoDB package to use.
16485 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
16486 The configuration file for MongoDB.
16488 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
16489 This value is used to create the directory, so that it exists and is
16490 owned by the mongodb user. It should match the data-directory which
16491 MongoDB is configured to use through the configuration file.
16495 @defvr {Scheme Variable} redis-service-type
16496 This is the service type for the @uref{https://redis.io/, Redis}
16497 key/value store, whose value is a @code{redis-configuration} object.
16500 @deftp {Data Type} redis-configuration
16501 Data type representing the configuration of redis.
16504 @item @code{redis} (default: @code{redis})
16505 The Redis package to use.
16507 @item @code{bind} (default: @code{"127.0.0.1"})
16508 Network interface on which to listen.
16510 @item @code{port} (default: @code{6379})
16511 Port on which to accept connections on, a value of 0 will disable
16512 listening on a TCP socket.
16514 @item @code{working-directory} (default: @code{"/var/lib/redis"})
16515 Directory in which to store the database and related files.
16519 @node Mail Services
16520 @subsection Mail Services
16524 The @code{(gnu services mail)} module provides Guix service definitions
16525 for email services: IMAP, POP3, and LMTP servers, as well as mail
16526 transport agents (MTAs). Lots of acronyms! These services are detailed
16527 in the subsections below.
16529 @subsubheading Dovecot Service
16531 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
16532 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
16535 By default, Dovecot does not need much configuration; the default
16536 configuration object created by @code{(dovecot-configuration)} will
16537 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
16538 certificate will be generated for TLS-protected connections, though
16539 Dovecot will also listen on cleartext ports by default. There are a
16540 number of options, though, which mail administrators might need to change,
16541 and as is the case with other services, Guix allows the system
16542 administrator to specify these parameters via a uniform Scheme interface.
16544 For example, to specify that mail is located at @code{maildir~/.mail},
16545 one would instantiate the Dovecot service like this:
16548 (dovecot-service #:config
16549 (dovecot-configuration
16550 (mail-location "maildir:~/.mail")))
16553 The available configuration parameters follow. Each parameter
16554 definition is preceded by its type; for example, @samp{string-list foo}
16555 indicates that the @code{foo} parameter should be specified as a list of
16556 strings. There is also a way to specify the configuration as a string,
16557 if you have an old @code{dovecot.conf} file that you want to port over
16558 from some other system; see the end for more details.
16560 @c The following documentation was initially generated by
16561 @c (generate-documentation) in (gnu services mail). Manually maintained
16562 @c documentation is better, so we shouldn't hesitate to edit below as
16563 @c needed. However if the change you want to make to this documentation
16564 @c can be done in an automated way, it's probably easier to change
16565 @c (generate-documentation) than to make it below and have to deal with
16566 @c the churn as dovecot updates.
16568 Available @code{dovecot-configuration} fields are:
16570 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
16571 The dovecot package.
16574 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
16575 A list of IPs or hosts where to listen for connections. @samp{*}
16576 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
16577 interfaces. If you want to specify non-default ports or anything more
16578 complex, customize the address and port fields of the
16579 @samp{inet-listener} of the specific services you are interested in.
16582 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
16583 List of protocols we want to serve. Available protocols include
16584 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
16586 Available @code{protocol-configuration} fields are:
16588 @deftypevr {@code{protocol-configuration} parameter} string name
16589 The name of the protocol.
16592 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
16593 UNIX socket path to the master authentication server to find users.
16594 This is used by imap (for shared users) and lda.
16595 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16598 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
16599 Space separated list of plugins to load.
16602 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
16603 Maximum number of IMAP connections allowed for a user from each IP
16604 address. NOTE: The username is compared case-sensitively.
16605 Defaults to @samp{10}.
16610 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
16611 List of services to enable. Available services include @samp{imap},
16612 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
16615 Available @code{service-configuration} fields are:
16617 @deftypevr {@code{service-configuration} parameter} string kind
16618 The service kind. Valid values include @code{director},
16619 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
16620 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
16621 @code{tcpwrap}, @code{quota-warning}, or anything else.
16624 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
16625 Listeners for the service. A listener is either a
16626 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
16627 an @code{inet-listener-configuration}.
16628 Defaults to @samp{()}.
16630 Available @code{unix-listener-configuration} fields are:
16632 @deftypevr {@code{unix-listener-configuration} parameter} string path
16633 Path to the file, relative to @code{base-dir} field. This is also used as
16637 @deftypevr {@code{unix-listener-configuration} parameter} string mode
16638 The access mode for the socket.
16639 Defaults to @samp{"0600"}.
16642 @deftypevr {@code{unix-listener-configuration} parameter} string user
16643 The user to own the socket.
16644 Defaults to @samp{""}.
16647 @deftypevr {@code{unix-listener-configuration} parameter} string group
16648 The group to own the socket.
16649 Defaults to @samp{""}.
16653 Available @code{fifo-listener-configuration} fields are:
16655 @deftypevr {@code{fifo-listener-configuration} parameter} string path
16656 Path to the file, relative to @code{base-dir} field. This is also used as
16660 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
16661 The access mode for the socket.
16662 Defaults to @samp{"0600"}.
16665 @deftypevr {@code{fifo-listener-configuration} parameter} string user
16666 The user to own the socket.
16667 Defaults to @samp{""}.
16670 @deftypevr {@code{fifo-listener-configuration} parameter} string group
16671 The group to own the socket.
16672 Defaults to @samp{""}.
16676 Available @code{inet-listener-configuration} fields are:
16678 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
16679 The protocol to listen for.
16682 @deftypevr {@code{inet-listener-configuration} parameter} string address
16683 The address on which to listen, or empty for all addresses.
16684 Defaults to @samp{""}.
16687 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
16688 The port on which to listen.
16691 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
16692 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
16694 Defaults to @samp{#t}.
16699 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
16700 Maximum number of simultaneous client connections per process. Once
16701 this number of connections is received, the next incoming connection
16702 will prompt Dovecot to spawn another process. If set to 0,
16703 @code{default-client-limit} is used instead.
16705 Defaults to @samp{0}.
16709 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
16710 Number of connections to handle before starting a new process.
16711 Typically the only useful values are 0 (unlimited) or 1. 1 is more
16712 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
16713 Defaults to @samp{1}.
16717 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
16718 Maximum number of processes that can exist for this service. If set to
16719 0, @code{default-process-limit} is used instead.
16721 Defaults to @samp{0}.
16725 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
16726 Number of processes to always keep waiting for more connections.
16727 Defaults to @samp{0}.
16730 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
16731 If you set @samp{service-count 0}, you probably need to grow
16733 Defaults to @samp{256000000}.
16738 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
16739 Dict configuration, as created by the @code{dict-configuration}
16742 Available @code{dict-configuration} fields are:
16744 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
16745 A list of key-value pairs that this dict should hold.
16746 Defaults to @samp{()}.
16751 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
16752 A list of passdb configurations, each one created by the
16753 @code{passdb-configuration} constructor.
16755 Available @code{passdb-configuration} fields are:
16757 @deftypevr {@code{passdb-configuration} parameter} string driver
16758 The driver that the passdb should use. Valid values include
16759 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
16761 Defaults to @samp{"pam"}.
16764 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
16765 Space separated list of arguments to the passdb driver.
16766 Defaults to @samp{""}.
16771 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
16772 List of userdb configurations, each one created by the
16773 @code{userdb-configuration} constructor.
16775 Available @code{userdb-configuration} fields are:
16777 @deftypevr {@code{userdb-configuration} parameter} string driver
16778 The driver that the userdb should use. Valid values include
16779 @samp{passwd} and @samp{static}.
16780 Defaults to @samp{"passwd"}.
16783 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
16784 Space separated list of arguments to the userdb driver.
16785 Defaults to @samp{""}.
16788 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
16789 Override fields from passwd.
16790 Defaults to @samp{()}.
16795 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
16796 Plug-in configuration, created by the @code{plugin-configuration}
16800 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
16801 List of namespaces. Each item in the list is created by the
16802 @code{namespace-configuration} constructor.
16804 Available @code{namespace-configuration} fields are:
16806 @deftypevr {@code{namespace-configuration} parameter} string name
16807 Name for this namespace.
16810 @deftypevr {@code{namespace-configuration} parameter} string type
16811 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
16812 Defaults to @samp{"private"}.
16815 @deftypevr {@code{namespace-configuration} parameter} string separator
16816 Hierarchy separator to use. You should use the same separator for
16817 all namespaces or some clients get confused. @samp{/} is usually a good
16818 one. The default however depends on the underlying mail storage
16820 Defaults to @samp{""}.
16823 @deftypevr {@code{namespace-configuration} parameter} string prefix
16824 Prefix required to access this namespace. This needs to be
16825 different for all namespaces. For example @samp{Public/}.
16826 Defaults to @samp{""}.
16829 @deftypevr {@code{namespace-configuration} parameter} string location
16830 Physical location of the mailbox. This is in the same format as
16831 mail_location, which is also the default for it.
16832 Defaults to @samp{""}.
16835 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
16836 There can be only one INBOX, and this setting defines which
16838 Defaults to @samp{#f}.
16841 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
16842 If namespace is hidden, it's not advertised to clients via NAMESPACE
16843 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
16844 useful when converting from another server with different namespaces
16845 which you want to deprecate but still keep working. For example you can
16846 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
16848 Defaults to @samp{#f}.
16851 @deftypevr {@code{namespace-configuration} parameter} boolean list?
16852 Show the mailboxes under this namespace with the LIST command. This
16853 makes the namespace visible for clients that do not support the NAMESPACE
16854 extension. The special @code{children} value lists child mailboxes, but
16855 hides the namespace prefix.
16856 Defaults to @samp{#t}.
16859 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
16860 Namespace handles its own subscriptions. If set to @code{#f}, the
16861 parent namespace handles them. The empty prefix should always have this
16863 Defaults to @samp{#t}.
16866 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
16867 List of predefined mailboxes in this namespace.
16868 Defaults to @samp{()}.
16870 Available @code{mailbox-configuration} fields are:
16872 @deftypevr {@code{mailbox-configuration} parameter} string name
16873 Name for this mailbox.
16876 @deftypevr {@code{mailbox-configuration} parameter} string auto
16877 @samp{create} will automatically create this mailbox.
16878 @samp{subscribe} will both create and subscribe to the mailbox.
16879 Defaults to @samp{"no"}.
16882 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
16883 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
16884 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
16885 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
16886 Defaults to @samp{()}.
16893 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
16894 Base directory where to store runtime data.
16895 Defaults to @samp{"/var/run/dovecot/"}.
16898 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
16899 Greeting message for clients.
16900 Defaults to @samp{"Dovecot ready."}.
16903 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
16904 List of trusted network ranges. Connections from these IPs are
16905 allowed to override their IP addresses and ports (for logging and for
16906 authentication checks). @samp{disable-plaintext-auth} is also ignored
16907 for these networks. Typically you would specify your IMAP proxy servers
16909 Defaults to @samp{()}.
16912 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
16913 List of login access check sockets (e.g.@: tcpwrap).
16914 Defaults to @samp{()}.
16917 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
16918 Show more verbose process titles (in ps). Currently shows user name
16919 and IP address. Useful for seeing who is actually using the IMAP
16920 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
16922 Defaults to @samp{#f}.
16925 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
16926 Should all processes be killed when Dovecot master process shuts down.
16927 Setting this to @code{#f} means that Dovecot can be upgraded without
16928 forcing existing client connections to close (although that could also
16929 be a problem if the upgrade is e.g.@: due to a security fix).
16930 Defaults to @samp{#t}.
16933 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
16934 If non-zero, run mail commands via this many connections to doveadm
16935 server, instead of running them directly in the same process.
16936 Defaults to @samp{0}.
16939 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
16940 UNIX socket or host:port used for connecting to doveadm server.
16941 Defaults to @samp{"doveadm-server"}.
16944 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
16945 List of environment variables that are preserved on Dovecot startup
16946 and passed down to all of its child processes. You can also give
16947 key=value pairs to always set specific settings.
16950 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
16951 Disable LOGIN command and all other plaintext authentications unless
16952 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
16953 matches the local IP (i.e.@: you're connecting from the same computer),
16954 the connection is considered secure and plaintext authentication is
16955 allowed. See also ssl=required setting.
16956 Defaults to @samp{#t}.
16959 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
16960 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
16961 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
16962 for caching to be used.
16963 Defaults to @samp{0}.
16966 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
16967 Time to live for cached data. After TTL expires the cached record
16968 is no longer used, *except* if the main database lookup returns internal
16969 failure. We also try to handle password changes automatically: If
16970 user's previous authentication was successful, but this one wasn't, the
16971 cache isn't used. For now this works only with plaintext
16973 Defaults to @samp{"1 hour"}.
16976 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
16977 TTL for negative hits (user not found, password mismatch).
16978 0 disables caching them completely.
16979 Defaults to @samp{"1 hour"}.
16982 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
16983 List of realms for SASL authentication mechanisms that need them.
16984 You can leave it empty if you don't want to support multiple realms.
16985 Many clients simply use the first one listed here, so keep the default
16987 Defaults to @samp{()}.
16990 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
16991 Default realm/domain to use if none was specified. This is used for
16992 both SASL realms and appending @@domain to username in plaintext
16994 Defaults to @samp{""}.
16997 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
16998 List of allowed characters in username. If the user-given username
16999 contains a character not listed in here, the login automatically fails.
17000 This is just an extra check to make sure user can't exploit any
17001 potential quote escaping vulnerabilities with SQL/LDAP databases. If
17002 you want to allow all characters, set this value to empty.
17003 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
17006 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
17007 Username character translations before it's looked up from
17008 databases. The value contains series of from -> to characters. For
17009 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
17010 translated to @samp{@@}.
17011 Defaults to @samp{""}.
17014 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
17015 Username formatting before it's looked up from databases. You can
17016 use the standard variables here, e.g.@: %Lu would lowercase the username,
17017 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
17018 change the @samp{@@} into @samp{-AT-}. This translation is done after
17019 @samp{auth-username-translation} changes.
17020 Defaults to @samp{"%Lu"}.
17023 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
17024 If you want to allow master users to log in by specifying the master
17025 username within the normal username string (i.e.@: not using SASL
17026 mechanism's support for it), you can specify the separator character
17027 here. The format is then <username><separator><master username>.
17028 UW-IMAP uses @samp{*} as the separator, so that could be a good
17030 Defaults to @samp{""}.
17033 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
17034 Username to use for users logging in with ANONYMOUS SASL
17036 Defaults to @samp{"anonymous"}.
17039 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
17040 Maximum number of dovecot-auth worker processes. They're used to
17041 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
17042 They're automatically created and destroyed as needed.
17043 Defaults to @samp{30}.
17046 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
17047 Host name to use in GSSAPI principal names. The default is to use
17048 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
17049 allow all keytab entries.
17050 Defaults to @samp{""}.
17053 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
17054 Kerberos keytab to use for the GSSAPI mechanism. Will use the
17055 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
17056 need to change the auth service to run as root to be able to read this
17058 Defaults to @samp{""}.
17061 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
17062 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
17063 and @samp{ntlm-auth} helper.
17064 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
17065 Defaults to @samp{#f}.
17068 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
17069 Path for Samba's @samp{ntlm-auth} helper binary.
17070 Defaults to @samp{"/usr/bin/ntlm_auth"}.
17073 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
17074 Time to delay before replying to failed authentications.
17075 Defaults to @samp{"2 secs"}.
17078 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
17079 Require a valid SSL client certificate or the authentication
17081 Defaults to @samp{#f}.
17084 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
17085 Take the username from client's SSL certificate, using
17086 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
17088 Defaults to @samp{#f}.
17091 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
17092 List of wanted authentication mechanisms. Supported mechanisms are:
17093 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
17094 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
17095 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
17096 @samp{disable-plaintext-auth} setting.
17099 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
17100 List of IPs or hostnames to all director servers, including ourself.
17101 Ports can be specified as ip:port. The default port is the same as what
17102 director service's @samp{inet-listener} is using.
17103 Defaults to @samp{()}.
17106 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
17107 List of IPs or hostnames to all backend mail servers. Ranges are
17108 allowed too, like 10.0.0.10-10.0.0.30.
17109 Defaults to @samp{()}.
17112 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
17113 How long to redirect users to a specific server after it no longer
17114 has any connections.
17115 Defaults to @samp{"15 min"}.
17118 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
17119 How the username is translated before being hashed. Useful values
17120 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
17121 are shared within domain.
17122 Defaults to @samp{"%Lu"}.
17125 @deftypevr {@code{dovecot-configuration} parameter} string log-path
17126 Log file to use for error messages. @samp{syslog} logs to syslog,
17127 @samp{/dev/stderr} logs to stderr.
17128 Defaults to @samp{"syslog"}.
17131 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
17132 Log file to use for informational messages. Defaults to
17134 Defaults to @samp{""}.
17137 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
17138 Log file to use for debug messages. Defaults to
17139 @samp{info-log-path}.
17140 Defaults to @samp{""}.
17143 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
17144 Syslog facility to use if you're logging to syslog. Usually if you
17145 don't want to use @samp{mail}, you'll use local0..local7. Also other
17146 standard facilities are supported.
17147 Defaults to @samp{"mail"}.
17150 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
17151 Log unsuccessful authentication attempts and the reasons why they
17153 Defaults to @samp{#f}.
17156 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
17157 In case of password mismatches, log the attempted password. Valid
17158 values are no, plain and sha1. sha1 can be useful for detecting brute
17159 force password attempts vs. user simply trying the same password over
17160 and over again. You can also truncate the value to n chars by appending
17161 ":n" (e.g.@: sha1:6).
17162 Defaults to @samp{"no"}.
17165 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
17166 Even more verbose logging for debugging purposes. Shows for example
17168 Defaults to @samp{#f}.
17171 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
17172 In case of password mismatches, log the passwords and used scheme so
17173 the problem can be debugged. Enabling this also enables
17175 Defaults to @samp{#f}.
17178 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
17179 Enable mail process debugging. This can help you figure out why
17180 Dovecot isn't finding your mails.
17181 Defaults to @samp{#f}.
17184 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
17185 Show protocol level SSL errors.
17186 Defaults to @samp{#f}.
17189 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
17190 Prefix for each line written to log file. % codes are in
17191 strftime(3) format.
17192 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
17195 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
17196 List of elements we want to log. The elements which have a
17197 non-empty variable value are joined together to form a comma-separated
17201 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
17202 Login log format. %s contains @samp{login-log-format-elements}
17203 string, %$ contains the data we want to log.
17204 Defaults to @samp{"%$: %s"}.
17207 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
17208 Log prefix for mail processes. See doc/wiki/Variables.txt for list
17209 of possible variables you can use.
17210 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
17213 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
17214 Format to use for logging mail deliveries. You can use variables:
17217 Delivery status message (e.g.@: @samp{saved to INBOX})
17229 Defaults to @samp{"msgid=%m: %$"}.
17232 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
17233 Location for users' mailboxes. The default is empty, which means
17234 that Dovecot tries to find the mailboxes automatically. This won't work
17235 if the user doesn't yet have any mail, so you should explicitly tell
17236 Dovecot the full location.
17238 If you're using mbox, giving a path to the INBOX
17239 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
17240 where the other mailboxes are kept. This is called the @emph{root mail
17241 directory}, and it must be the first path given in the
17242 @samp{mail-location} setting.
17244 There are a few special variables you can use, e.g.:
17250 user part in user@@domain, same as %u if there's no domain
17252 domain part in user@@domain, empty if there's no domain
17257 See doc/wiki/Variables.txt for full list. Some examples:
17259 @item maildir:~/Maildir
17260 @item mbox:~/mail:INBOX=/var/mail/%u
17261 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
17263 Defaults to @samp{""}.
17266 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
17267 System user and group used to access mails. If you use multiple,
17268 userdb can override these by returning uid or gid fields. You can use
17269 either numbers or names. <doc/wiki/UserIds.txt>.
17270 Defaults to @samp{""}.
17273 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
17275 Defaults to @samp{""}.
17278 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
17279 Group to enable temporarily for privileged operations. Currently
17280 this is used only with INBOX when either its initial creation or
17281 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
17283 Defaults to @samp{""}.
17286 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
17287 Grant access to these supplementary groups for mail processes.
17288 Typically these are used to set up access to shared mailboxes. Note
17289 that it may be dangerous to set these if users can create symlinks
17290 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
17291 could allow a user to delete others' mailboxes, or @code{ln -s
17292 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
17296 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
17297 Allow full file system access to clients. There's no access checks
17298 other than what the operating system does for the active UID/GID. It
17299 works with both maildir and mboxes, allowing you to prefix mailboxes
17300 names with e.g.@: @file{/path/} or @file{~user/}.
17301 Defaults to @samp{#f}.
17304 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
17305 Don't use @code{mmap()} at all. This is required if you store indexes to
17306 shared file systems (NFS or clustered file system).
17307 Defaults to @samp{#f}.
17310 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
17311 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
17312 supports @samp{O_EXCL} since version 3, so this should be safe to use
17313 nowadays by default.
17314 Defaults to @samp{#t}.
17317 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
17318 When to use fsync() or fdatasync() calls:
17321 Whenever necessary to avoid losing important data
17323 Useful with e.g.@: NFS when @code{write()}s are delayed
17325 Never use it (best performance, but crashes can lose data).
17327 Defaults to @samp{"optimized"}.
17330 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
17331 Mail storage exists in NFS. Set this to yes to make Dovecot flush
17332 NFS caches whenever needed. If you're using only a single mail server
17334 Defaults to @samp{#f}.
17337 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
17338 Mail index files also exist in NFS. Setting this to yes requires
17339 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
17340 Defaults to @samp{#f}.
17343 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
17344 Locking method for index files. Alternatives are fcntl, flock and
17345 dotlock. Dotlocking uses some tricks which may create more disk I/O
17346 than other locking methods. NFS users: flock doesn't work, remember to
17347 change @samp{mmap-disable}.
17348 Defaults to @samp{"fcntl"}.
17351 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
17352 Directory in which LDA/LMTP temporarily stores incoming mails >128
17354 Defaults to @samp{"/tmp"}.
17357 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
17358 Valid UID range for users. This is mostly to make sure that users can't
17359 log in as daemons or other system users. Note that denying root logins is
17360 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
17362 Defaults to @samp{500}.
17365 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
17367 Defaults to @samp{0}.
17370 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
17371 Valid GID range for users. Users having non-valid GID as primary group ID
17372 aren't allowed to log in. If user belongs to supplementary groups with
17373 non-valid GIDs, those groups are not set.
17374 Defaults to @samp{1}.
17377 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
17379 Defaults to @samp{0}.
17382 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
17383 Maximum allowed length for mail keyword name. It's only forced when
17384 trying to create new keywords.
17385 Defaults to @samp{50}.
17388 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
17389 List of directories under which chrooting is allowed for mail
17390 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
17391 too). This setting doesn't affect @samp{login-chroot}
17392 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
17393 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
17394 which local users can modify, that may lead to root exploit. Usually
17395 this should be done only if you don't allow shell access for users.
17396 <doc/wiki/Chrooting.txt>.
17397 Defaults to @samp{()}.
17400 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
17401 Default chroot directory for mail processes. This can be overridden
17402 for specific users in user database by giving @samp{/./} in user's home
17403 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
17404 there is no real need to do chrooting, Dovecot doesn't allow users to
17405 access files outside their mail directory anyway. If your home
17406 directories are prefixed with the chroot directory, append @samp{/.} to
17407 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
17408 Defaults to @samp{""}.
17411 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
17412 UNIX socket path to master authentication server to find users.
17413 This is used by imap (for shared users) and lda.
17414 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17417 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
17418 Directory where to look up mail plugins.
17419 Defaults to @samp{"/usr/lib/dovecot"}.
17422 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
17423 List of plugins to load for all services. Plugins specific to IMAP,
17424 LDA, etc.@: are added to this list in their own .conf files.
17425 Defaults to @samp{()}.
17428 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
17429 The minimum number of mails in a mailbox before updates are done to
17430 cache file. This allows optimizing Dovecot's behavior to do less disk
17431 writes at the cost of more disk reads.
17432 Defaults to @samp{0}.
17435 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
17436 When IDLE command is running, mailbox is checked once in a while to
17437 see if there are any new mails or other changes. This setting defines
17438 the minimum time to wait between those checks. Dovecot can also use
17439 dnotify, inotify and kqueue to find out immediately when changes
17441 Defaults to @samp{"30 secs"}.
17444 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
17445 Save mails with CR+LF instead of plain LF. This makes sending those
17446 mails take less CPU, especially with sendfile() syscall with Linux and
17447 FreeBSD. But it also creates a bit more disk I/O which may just make it
17448 slower. Also note that if other software reads the mboxes/maildirs,
17449 they may handle the extra CRs wrong and cause problems.
17450 Defaults to @samp{#f}.
17453 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
17454 By default LIST command returns all entries in maildir beginning
17455 with a dot. Enabling this option makes Dovecot return only entries
17456 which are directories. This is done by stat()ing each entry, so it
17457 causes more disk I/O.
17458 (For systems setting struct @samp{dirent->d_type} this check is free
17459 and it's done always regardless of this setting).
17460 Defaults to @samp{#f}.
17463 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
17464 When copying a message, do it with hard links whenever possible.
17465 This makes the performance much better, and it's unlikely to have any
17467 Defaults to @samp{#t}.
17470 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
17471 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
17472 directory only when its mtime changes unexpectedly or when we can't find
17473 the mail otherwise.
17474 Defaults to @samp{#f}.
17477 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
17478 Which locking methods to use for locking mbox. There are four
17483 Create <mailbox>.lock file. This is the oldest and most NFS-safe
17484 solution. If you want to use /var/mail/ like directory, the users will
17485 need write access to that directory.
17487 Same as dotlock, but if it fails because of permissions or because there
17488 isn't enough disk space, just skip it.
17490 Use this if possible. Works with NFS too if lockd is used.
17492 May not exist in all systems. Doesn't work with NFS.
17494 May not exist in all systems. Doesn't work with NFS.
17497 You can use multiple locking methods; if you do the order they're declared
17498 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
17499 locking methods as well. Some operating systems don't allow using some of
17500 them simultaneously.
17503 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
17507 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
17508 Maximum time to wait for lock (all of them) before aborting.
17509 Defaults to @samp{"5 mins"}.
17512 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
17513 If dotlock exists but the mailbox isn't modified in any way,
17514 override the lock file after this much time.
17515 Defaults to @samp{"2 mins"}.
17518 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
17519 When mbox changes unexpectedly we have to fully read it to find out
17520 what changed. If the mbox is large this can take a long time. Since
17521 the change is usually just a newly appended mail, it'd be faster to
17522 simply read the new mails. If this setting is enabled, Dovecot does
17523 this but still safely fallbacks to re-reading the whole mbox file
17524 whenever something in mbox isn't how it's expected to be. The only real
17525 downside to this setting is that if some other MUA changes message
17526 flags, Dovecot doesn't notice it immediately. Note that a full sync is
17527 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
17528 Defaults to @samp{#t}.
17531 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
17532 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
17533 EXAMINE, EXPUNGE or CHECK commands. If this is set,
17534 @samp{mbox-dirty-syncs} is ignored.
17535 Defaults to @samp{#f}.
17538 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
17539 Delay writing mbox headers until doing a full write sync (EXPUNGE
17540 and CHECK commands and when closing the mailbox). This is especially
17541 useful for POP3 where clients often delete all mails. The downside is
17542 that our changes aren't immediately visible to other MUAs.
17543 Defaults to @samp{#t}.
17546 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
17547 If mbox size is smaller than this (e.g.@: 100k), don't write index
17548 files. If an index file already exists it's still read, just not
17550 Defaults to @samp{0}.
17553 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
17554 Maximum dbox file size until it's rotated.
17555 Defaults to @samp{10000000}.
17558 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
17559 Maximum dbox file age until it's rotated. Typically in days. Day
17560 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
17562 Defaults to @samp{"1d"}.
17565 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
17566 When creating new mdbox files, immediately preallocate their size to
17567 @samp{mdbox-rotate-size}. This setting currently works only in Linux
17568 with some file systems (ext4, xfs).
17569 Defaults to @samp{#f}.
17572 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
17573 sdbox and mdbox support saving mail attachments to external files,
17574 which also allows single instance storage for them. Other backends
17575 don't support this for now.
17577 WARNING: This feature hasn't been tested much yet. Use at your own risk.
17579 Directory root where to store mail attachments. Disabled, if empty.
17580 Defaults to @samp{""}.
17583 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
17584 Attachments smaller than this aren't saved externally. It's also
17585 possible to write a plugin to disable saving specific attachments
17587 Defaults to @samp{128000}.
17590 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
17591 File system backend to use for saving attachments:
17594 No SiS done by Dovecot (but this might help FS's own deduplication)
17596 SiS with immediate byte-by-byte comparison during saving
17597 @item sis-queue posix
17598 SiS with delayed comparison and deduplication.
17600 Defaults to @samp{"sis posix"}.
17603 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
17604 Hash format to use in attachment filenames. You can add any text and
17605 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
17606 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
17607 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
17608 Defaults to @samp{"%@{sha1@}"}.
17611 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
17613 Defaults to @samp{100}.
17616 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
17618 Defaults to @samp{1000}.
17621 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
17622 Default VSZ (virtual memory size) limit for service processes.
17623 This is mainly intended to catch and kill processes that leak memory
17624 before they eat up everything.
17625 Defaults to @samp{256000000}.
17628 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
17629 Login user is internally used by login processes. This is the most
17630 untrusted user in Dovecot system. It shouldn't have access to anything
17632 Defaults to @samp{"dovenull"}.
17635 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
17636 Internal user is used by unprivileged processes. It should be
17637 separate from login user, so that login processes can't disturb other
17639 Defaults to @samp{"dovecot"}.
17642 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
17643 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
17644 Defaults to @samp{"required"}.
17647 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
17648 PEM encoded X.509 SSL/TLS certificate (public key).
17649 Defaults to @samp{"</etc/dovecot/default.pem"}.
17652 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
17653 PEM encoded SSL/TLS private key. The key is opened before
17654 dropping root privileges, so keep the key file unreadable by anyone but
17656 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
17659 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
17660 If key file is password protected, give the password here.
17661 Alternatively give it when starting dovecot with -p parameter. Since
17662 this file is often world-readable, you may want to place this setting
17663 instead to a different.
17664 Defaults to @samp{""}.
17667 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
17668 PEM encoded trusted certificate authority. Set this only if you
17669 intend to use @samp{ssl-verify-client-cert? #t}. The file should
17670 contain the CA certificate(s) followed by the matching
17671 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
17672 Defaults to @samp{""}.
17675 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
17676 Require that CRL check succeeds for client certificates.
17677 Defaults to @samp{#t}.
17680 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
17681 Request client to send a certificate. If you also want to require
17682 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
17683 Defaults to @samp{#f}.
17686 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
17687 Which field from certificate to use for username. commonName and
17688 x500UniqueIdentifier are the usual choices. You'll also need to set
17689 @samp{auth-ssl-username-from-cert? #t}.
17690 Defaults to @samp{"commonName"}.
17693 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
17694 Minimum SSL protocol version to accept.
17695 Defaults to @samp{"TLSv1"}.
17698 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
17699 SSL ciphers to use.
17700 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
17703 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
17704 SSL crypto device to use, for valid values run "openssl engine".
17705 Defaults to @samp{""}.
17708 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
17709 Address to use when sending rejection mails.
17710 %d expands to recipient domain.
17711 Defaults to @samp{"postmaster@@%d"}.
17714 @deftypevr {@code{dovecot-configuration} parameter} string hostname
17715 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
17716 and in LMTP replies. Default is the system's real hostname@@domain.
17717 Defaults to @samp{""}.
17720 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
17721 If user is over quota, return with temporary failure instead of
17723 Defaults to @samp{#f}.
17726 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
17727 Binary to use for sending mails.
17728 Defaults to @samp{"/usr/sbin/sendmail"}.
17731 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
17732 If non-empty, send mails via this SMTP host[:port] instead of
17734 Defaults to @samp{""}.
17737 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
17738 Subject: header to use for rejection mails. You can use the same
17739 variables as for @samp{rejection-reason} below.
17740 Defaults to @samp{"Rejected: %s"}.
17743 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
17744 Human readable error message for rejection mails. You can use
17757 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
17760 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
17761 Delimiter character between local-part and detail in email
17763 Defaults to @samp{"+"}.
17766 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
17767 Header where the original recipient address (SMTP's RCPT TO:
17768 address) is taken from if not available elsewhere. With dovecot-lda -a
17769 parameter overrides this. A commonly used header for this is
17771 Defaults to @samp{""}.
17774 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
17775 Should saving a mail to a nonexistent mailbox automatically create
17777 Defaults to @samp{#f}.
17780 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
17781 Should automatically created mailboxes be also automatically
17783 Defaults to @samp{#f}.
17786 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
17787 Maximum IMAP command line length. Some clients generate very long
17788 command lines with huge mailboxes, so you may need to raise this if you
17789 get "Too long argument" or "IMAP command line too large" errors
17791 Defaults to @samp{64000}.
17794 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
17795 IMAP logout format string:
17798 total number of bytes read from client
17800 total number of bytes sent to client.
17802 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
17803 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@}"}.
17806 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
17807 Override the IMAP CAPABILITY response. If the value begins with '+',
17808 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
17809 Defaults to @samp{""}.
17812 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
17813 How long to wait between "OK Still here" notifications when client
17815 Defaults to @samp{"2 mins"}.
17818 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
17819 ID field names and values to send to clients. Using * as the value
17820 makes Dovecot use the default value. The following fields have default
17821 values currently: name, version, os, os-version, support-url,
17823 Defaults to @samp{""}.
17826 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
17827 ID fields sent by client to log. * means everything.
17828 Defaults to @samp{""}.
17831 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
17832 Workarounds for various client bugs:
17835 @item delay-newmail
17836 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
17837 CHECK commands. Some clients ignore them otherwise, for example OSX
17838 Mail (<v2.1). Outlook Express breaks more badly though, without this it
17839 may show user "Message no longer in server" errors. Note that OE6
17840 still breaks even with this workaround if synchronization is set to
17843 @item tb-extra-mailbox-sep
17844 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
17845 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
17846 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
17848 @item tb-lsub-flags
17849 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
17850 This makes Thunderbird realize they aren't selectable and show them
17851 greyed out, instead of only later giving "not selectable" popup error.
17853 Defaults to @samp{()}.
17856 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
17857 Host allowed in URLAUTH URLs sent by client. "*" allows all.
17858 Defaults to @samp{""}.
17862 Whew! Lots of configuration options. The nice thing about it though is
17863 that Guix has a complete interface to Dovecot's configuration
17864 language. This allows not only a nice way to declare configurations,
17865 but also offers reflective capabilities as well: users can write code to
17866 inspect and transform configurations from within Scheme.
17868 However, it could be that you just want to get a @code{dovecot.conf} up
17869 and running. In that case, you can pass an
17870 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
17871 @code{dovecot-service}. As its name indicates, an opaque configuration
17872 does not have easy reflective capabilities.
17874 Available @code{opaque-dovecot-configuration} fields are:
17876 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
17877 The dovecot package.
17880 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
17881 The contents of the @code{dovecot.conf}, as a string.
17884 For example, if your @code{dovecot.conf} is just the empty string, you
17885 could instantiate a dovecot service like this:
17888 (dovecot-service #:config
17889 (opaque-dovecot-configuration
17893 @subsubheading OpenSMTPD Service
17895 @deffn {Scheme Variable} opensmtpd-service-type
17896 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
17897 service, whose value should be an @code{opensmtpd-configuration} object
17898 as in this example:
17901 (service opensmtpd-service-type
17902 (opensmtpd-configuration
17903 (config-file (local-file "./my-smtpd.conf"))))
17907 @deftp {Data Type} opensmtpd-configuration
17908 Data type representing the configuration of opensmtpd.
17911 @item @code{package} (default: @var{opensmtpd})
17912 Package object of the OpenSMTPD SMTP server.
17914 @item @code{config-file} (default: @code{%default-opensmtpd-file})
17915 File-like object of the OpenSMTPD configuration file to use. By default
17916 it listens on the loopback network interface, and allows for mail from
17917 users and daemons on the local machine, as well as permitting email to
17918 remote servers. Run @command{man smtpd.conf} for more information.
17923 @subsubheading Exim Service
17925 @cindex mail transfer agent (MTA)
17926 @cindex MTA (mail transfer agent)
17929 @deffn {Scheme Variable} exim-service-type
17930 This is the type of the @uref{https://exim.org, Exim} mail transfer
17931 agent (MTA), whose value should be an @code{exim-configuration} object
17932 as in this example:
17935 (service exim-service-type
17936 (exim-configuration
17937 (config-file (local-file "./my-exim.conf"))))
17941 In order to use an @code{exim-service-type} service you must also have a
17942 @code{mail-aliases-service-type} service present in your
17943 @code{operating-system} (even if it has no aliases).
17945 @deftp {Data Type} exim-configuration
17946 Data type representing the configuration of exim.
17949 @item @code{package} (default: @var{exim})
17950 Package object of the Exim server.
17952 @item @code{config-file} (default: @code{#f})
17953 File-like object of the Exim configuration file to use. If its value is
17954 @code{#f} then use the default configuration file from the package
17955 provided in @code{package}. The resulting configuration file is loaded
17956 after setting the @code{exim_user} and @code{exim_group} configuration
17962 @subsubheading Getmail service
17967 @deffn {Scheme Variable} getmail-service-type
17968 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
17969 mail retriever, whose value should be an @code{getmail-configuration}.
17972 Available @code{getmail-configuration} fields are:
17974 @deftypevr {@code{getmail-configuration} parameter} symbol name
17975 A symbol to identify the getmail service.
17977 Defaults to @samp{"unset"}.
17981 @deftypevr {@code{getmail-configuration} parameter} package package
17982 The getmail package to use.
17986 @deftypevr {@code{getmail-configuration} parameter} string user
17987 The user to run getmail as.
17989 Defaults to @samp{"getmail"}.
17993 @deftypevr {@code{getmail-configuration} parameter} string group
17994 The group to run getmail as.
17996 Defaults to @samp{"getmail"}.
18000 @deftypevr {@code{getmail-configuration} parameter} string directory
18001 The getmail directory to use.
18003 Defaults to @samp{"/var/lib/getmail/default"}.
18007 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
18008 The getmail configuration file to use.
18010 Available @code{getmail-configuration-file} fields are:
18012 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
18013 What mail account to retrieve mail from, and how to access that account.
18015 Available @code{getmail-retriever-configuration} fields are:
18017 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
18018 The type of mail retriever to use. Valid values include @samp{passwd}
18021 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
18025 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
18026 Username to login to the mail server with.
18028 Defaults to @samp{unset}.
18032 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
18033 Username to login to the mail server with.
18035 Defaults to @samp{unset}.
18039 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
18040 Port number to connect to.
18042 Defaults to @samp{#f}.
18046 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
18047 Override fields from passwd.
18049 Defaults to @samp{""}.
18053 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
18054 Override fields from passwd.
18056 Defaults to @samp{()}.
18060 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
18061 PEM-formatted key file to use for the TLS negotiation.
18063 Defaults to @samp{""}.
18067 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
18068 PEM-formatted certificate file to use for the TLS negotiation.
18070 Defaults to @samp{""}.
18074 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
18075 CA certificates to use.
18077 Defaults to @samp{""}.
18081 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
18082 Extra retriever parameters.
18084 Defaults to @samp{()}.
18090 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
18091 What to do with retrieved messages.
18093 Available @code{getmail-destination-configuration} fields are:
18095 @deftypevr {@code{getmail-destination-configuration} parameter} string type
18096 The type of mail destination. Valid values include @samp{Maildir},
18097 @samp{Mboxrd} and @samp{MDA_external}.
18099 Defaults to @samp{unset}.
18103 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
18104 The path option for the mail destination. The behaviour depends on the
18107 Defaults to @samp{""}.
18111 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
18112 Extra destination parameters
18114 Defaults to @samp{()}.
18120 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
18123 Available @code{getmail-options-configuration} fields are:
18125 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
18126 If set to @samp{0}, getmail will only print warnings and errors. A
18127 value of @samp{1} means that messages will be printed about retrieving
18128 and deleting messages. If set to @samp{2}, getmail will print messages
18129 about each of it's actions.
18131 Defaults to @samp{1}.
18135 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
18136 If true, getmail will retrieve all available messages. Otherwise it
18137 will only retrieve messages it hasn't seen previously.
18139 Defaults to @samp{#t}.
18143 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
18144 If set to true, messages will be deleted from the server after
18145 retrieving and successfully delivering them. Otherwise, messages will
18146 be left on the server.
18148 Defaults to @samp{#f}.
18152 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
18153 Getmail will delete messages this number of days after seeing them, if
18154 they have been delivered. This means messages will be left on the
18155 server this number of days after delivering them. A value of @samp{0}
18156 disabled this feature.
18158 Defaults to @samp{0}.
18162 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
18163 Delete messages larger than this of bytes after retrieving them, even if
18164 the delete and delete-after options are disabled. A value of @samp{0}
18165 disables this feature.
18167 Defaults to @samp{0}.
18171 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
18172 Retrieve messages totalling up to this number of bytes before closing
18173 the session with the server. A value of @samp{0} disables this feature.
18175 Defaults to @samp{0}.
18179 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
18180 Don't retrieve messages larger than this number of bytes. A value of
18181 @samp{0} disables this feature.
18183 Defaults to @samp{0}.
18187 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
18188 If true, getmail will add a Delivered-To header to messages.
18190 Defaults to @samp{#t}.
18194 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
18195 If set, getmail adds a Received header to the messages.
18197 Defaults to @samp{#t}.
18201 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
18202 Getmail will record a log of its actions to the named file. A value of
18203 @samp{""} disables this feature.
18205 Defaults to @samp{""}.
18209 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
18210 If true, getmail will record a log of its actions using the system
18213 Defaults to @samp{#f}.
18217 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
18218 If true, getmail will log information about messages not retrieved and
18219 the reason for not retrieving them, as well as starting and ending
18222 Defaults to @samp{#f}.
18226 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
18227 Extra options to include.
18229 Defaults to @samp{()}.
18237 @deftypevr {@code{getmail-configuration} parameter} list idle
18238 A list of mailboxes that getmail should wait on the server for new mail
18239 notifications. This depends on the server supporting the IDLE
18242 Defaults to @samp{()}.
18246 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
18247 Environment variables to set for getmail.
18249 Defaults to @samp{()}.
18253 @subsubheading Mail Aliases Service
18255 @cindex email aliases
18256 @cindex aliases, for email addresses
18258 @deffn {Scheme Variable} mail-aliases-service-type
18259 This is the type of the service which provides @code{/etc/aliases},
18260 specifying how to deliver mail to users on this system.
18263 (service mail-aliases-service-type
18264 '(("postmaster" "bob")
18265 ("bob" "bob@@example.com" "bob@@example2.com")))
18269 The configuration for a @code{mail-aliases-service-type} service is an
18270 association list denoting how to deliver mail that comes to this
18271 system. Each entry is of the form @code{(alias addresses ...)}, with
18272 @code{alias} specifying the local alias and @code{addresses} specifying
18273 where to deliver this user's mail.
18275 The aliases aren't required to exist as users on the local system. In
18276 the above example, there doesn't need to be a @code{postmaster} entry in
18277 the @code{operating-system}'s @code{user-accounts} in order to deliver
18278 the @code{postmaster} mail to @code{bob} (which subsequently would
18279 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
18281 @subsubheading GNU Mailutils IMAP4 Daemon
18282 @cindex GNU Mailutils IMAP4 Daemon
18284 @deffn {Scheme Variable} imap4d-service-type
18285 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
18286 mailutils, GNU Mailutils Manual}), whose value should be an
18287 @code{imap4d-configuration} object as in this example:
18290 (service imap4d-service-type
18291 (imap4d-configuration
18292 (config-file (local-file "imap4d.conf"))))
18296 @deftp {Data Type} imap4d-configuration
18297 Data type representing the configuration of @command{imap4d}.
18300 @item @code{package} (default: @code{mailutils})
18301 The package that provides @command{imap4d}.
18303 @item @code{config-file} (default: @code{%default-imap4d-config-file})
18304 File-like object of the configuration file to use, by default it will listen
18305 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
18306 Mailutils Manual}, for details.
18311 @node Messaging Services
18312 @subsection Messaging Services
18317 The @code{(gnu services messaging)} module provides Guix service
18318 definitions for messaging services: currently only Prosody is supported.
18320 @subsubheading Prosody Service
18322 @deffn {Scheme Variable} prosody-service-type
18323 This is the type for the @uref{https://prosody.im, Prosody XMPP
18324 communication server}. Its value must be a @code{prosody-configuration}
18325 record as in this example:
18328 (service prosody-service-type
18329 (prosody-configuration
18330 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
18333 (int-component-configuration
18334 (hostname "conference.example.net")
18336 (mod-muc (mod-muc-configuration)))))
18339 (virtualhost-configuration
18340 (domain "example.net"))))))
18343 See below for details about @code{prosody-configuration}.
18347 By default, Prosody does not need much configuration. Only one
18348 @code{virtualhosts} field is needed: it specifies the domain you wish
18351 You can perform various sanity checks on the generated configuration
18352 with the @code{prosodyctl check} command.
18354 Prosodyctl will also help you to import certificates from the
18355 @code{letsencrypt} directory so that the @code{prosody} user can access
18356 them. See @url{https://prosody.im/doc/letsencrypt}.
18359 prosodyctl --root cert import /etc/letsencrypt/live
18362 The available configuration parameters follow. Each parameter
18363 definition is preceded by its type; for example, @samp{string-list foo}
18364 indicates that the @code{foo} parameter should be specified as a list of
18365 strings. Types starting with @code{maybe-} denote parameters that won't
18366 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
18368 There is also a way to specify the configuration as a string, if you
18369 have an old @code{prosody.cfg.lua} file that you want to port over from
18370 some other system; see the end for more details.
18372 The @code{file-object} type designates either a file-like object
18373 (@pxref{G-Expressions, file-like objects}) or a file name.
18375 @c The following documentation was initially generated by
18376 @c (generate-documentation) in (gnu services messaging). Manually maintained
18377 @c documentation is better, so we shouldn't hesitate to edit below as
18378 @c needed. However if the change you want to make to this documentation
18379 @c can be done in an automated way, it's probably easier to change
18380 @c (generate-documentation) than to make it below and have to deal with
18381 @c the churn as Prosody updates.
18383 Available @code{prosody-configuration} fields are:
18385 @deftypevr {@code{prosody-configuration} parameter} package prosody
18386 The Prosody package.
18389 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
18390 Location of the Prosody data storage directory. See
18391 @url{https://prosody.im/doc/configure}.
18392 Defaults to @samp{"/var/lib/prosody"}.
18395 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
18396 Additional plugin directories. They are searched in all the specified
18397 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
18398 Defaults to @samp{()}.
18401 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
18402 Every virtual host and component needs a certificate so that clients and
18403 servers can securely verify its identity. Prosody will automatically load
18404 certificates/keys from the directory specified here.
18405 Defaults to @samp{"/etc/prosody/certs"}.
18408 @deftypevr {@code{prosody-configuration} parameter} string-list admins
18409 This is a list of accounts that are admins for the server. Note that you
18410 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
18411 @url{https://prosody.im/doc/creating_accounts}.
18412 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
18413 Defaults to @samp{()}.
18416 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
18417 Enable use of libevent for better performance under high load. See
18418 @url{https://prosody.im/doc/libevent}.
18419 Defaults to @samp{#f}.
18422 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
18423 This is the list of modules Prosody will load on startup. It looks for
18424 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
18425 Documentation on modules can be found at:
18426 @url{https://prosody.im/doc/modules}.
18427 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
18430 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
18431 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
18432 should you want to disable them then add them to this list.
18433 Defaults to @samp{()}.
18436 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
18437 Path to a text file where the shared groups are defined. If this path is
18438 empty then @samp{mod_groups} does nothing. See
18439 @url{https://prosody.im/doc/modules/mod_groups}.
18440 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
18443 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
18444 Disable account creation by default, for security. See
18445 @url{https://prosody.im/doc/creating_accounts}.
18446 Defaults to @samp{#f}.
18449 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
18450 These are the SSL/TLS-related settings. Most of them are disabled so to
18451 use Prosody's defaults. If you do not completely understand these options, do
18452 not add them to your config, it is easy to lower the security of your server
18453 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
18455 Available @code{ssl-configuration} fields are:
18457 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
18458 This determines what handshake to use.
18461 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
18462 Path to your private key file.
18465 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
18466 Path to your certificate file.
18469 @deftypevr {@code{ssl-configuration} parameter} file-object capath
18470 Path to directory containing root certificates that you wish Prosody to
18471 trust when verifying the certificates of remote servers.
18472 Defaults to @samp{"/etc/ssl/certs"}.
18475 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
18476 Path to a file containing root certificates that you wish Prosody to trust.
18477 Similar to @code{capath} but with all certificates concatenated together.
18480 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
18481 A list of verification options (these mostly map to OpenSSL's
18482 @code{set_verify()} flags).
18485 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
18486 A list of general options relating to SSL/TLS. These map to OpenSSL's
18487 @code{set_options()}. For a full list of options available in LuaSec, see the
18491 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
18492 How long a chain of certificate authorities to check when looking for a
18493 trusted root certificate.
18496 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
18497 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
18498 clients, and in what order.
18501 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
18502 A path to a file containing parameters for Diffie-Hellman key exchange. You
18503 can create such a file with:
18504 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
18507 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
18508 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
18509 @samp{"secp384r1"}.
18512 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
18513 A list of ``extra'' verification options.
18516 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
18517 Password for encrypted private keys.
18522 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
18523 Whether to force all client-to-server connections to be encrypted or not.
18524 See @url{https://prosody.im/doc/modules/mod_tls}.
18525 Defaults to @samp{#f}.
18528 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
18529 Set of mechanisms that will never be offered. See
18530 @url{https://prosody.im/doc/modules/mod_saslauth}.
18531 Defaults to @samp{("DIGEST-MD5")}.
18534 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
18535 Whether to force all server-to-server connections to be encrypted or not.
18536 See @url{https://prosody.im/doc/modules/mod_tls}.
18537 Defaults to @samp{#f}.
18540 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
18541 Whether to require encryption and certificate authentication. This
18542 provides ideal security, but requires servers you communicate with to support
18543 encryption AND present valid, trusted certificates. See
18544 @url{https://prosody.im/doc/s2s#security}.
18545 Defaults to @samp{#f}.
18548 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
18549 Many servers don't support encryption or have invalid or self-signed
18550 certificates. You can list domains here that will not be required to
18551 authenticate using certificates. They will be authenticated using DNS. See
18552 @url{https://prosody.im/doc/s2s#security}.
18553 Defaults to @samp{()}.
18556 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
18557 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
18558 valid certificates for some domains by specifying a list here. See
18559 @url{https://prosody.im/doc/s2s#security}.
18560 Defaults to @samp{()}.
18563 @deftypevr {@code{prosody-configuration} parameter} string authentication
18564 Select the authentication backend to use. The default provider stores
18565 passwords in plaintext and uses Prosody's configured data storage to store the
18566 authentication data. If you do not trust your server please see
18567 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
18568 about using the hashed backend. See also
18569 @url{https://prosody.im/doc/authentication}
18570 Defaults to @samp{"internal_plain"}.
18573 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
18574 Set logging options. Advanced logging configuration is not yet supported
18575 by the Prosody service. See @url{https://prosody.im/doc/logging}.
18576 Defaults to @samp{"*syslog"}.
18579 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
18580 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
18581 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
18584 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
18585 Maximum allowed size of the HTTP body (in bytes).
18588 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
18589 Some modules expose their own URL in various ways. This URL is built
18590 from the protocol, host and port used. If Prosody sits behind a proxy, the
18591 public URL will be @code{http-external-url} instead. See
18592 @url{https://prosody.im/doc/http#external_url}.
18595 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
18596 A host in Prosody is a domain on which user accounts can be created. For
18597 example if you want your users to have addresses like
18598 @samp{"john.smith@@example.com"} then you need to add a host
18599 @samp{"example.com"}. All options in this list will apply only to this host.
18601 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
18602 the actual physical host that Prosody is installed on. A single Prosody
18603 instance can serve many domains, each one defined as a VirtualHost entry in
18604 Prosody's configuration. Conversely a server that hosts a single domain would
18605 have just one VirtualHost entry.
18607 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
18609 Available @code{virtualhost-configuration} fields are:
18611 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:
18612 @deftypevr {@code{virtualhost-configuration} parameter} string domain
18613 Domain you wish Prosody to serve.
18618 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
18619 Components are extra services on a server which are available to clients,
18620 usually on a subdomain of the main server (such as
18621 @samp{"mycomponent.example.com"}). Example components might be chatroom
18622 servers, user directories, or gateways to other protocols.
18624 Internal components are implemented with Prosody-specific plugins. To add an
18625 internal component, you simply fill the hostname field, and the plugin you wish
18626 to use for the component.
18628 See @url{https://prosody.im/doc/components}.
18629 Defaults to @samp{()}.
18631 Available @code{int-component-configuration} fields are:
18633 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:
18634 @deftypevr {@code{int-component-configuration} parameter} string hostname
18635 Hostname of the component.
18638 @deftypevr {@code{int-component-configuration} parameter} string plugin
18639 Plugin you wish to use for the component.
18642 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
18643 Multi-user chat (MUC) is Prosody's module for allowing you to create
18644 hosted chatrooms/conferences for XMPP users.
18646 General information on setting up and using multi-user chatrooms can be found
18647 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
18648 which you should read if you are new to XMPP chatrooms.
18650 See also @url{https://prosody.im/doc/modules/mod_muc}.
18652 Available @code{mod-muc-configuration} fields are:
18654 @deftypevr {@code{mod-muc-configuration} parameter} string name
18655 The name to return in service discovery responses.
18656 Defaults to @samp{"Prosody Chatrooms"}.
18659 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
18660 If @samp{#t}, this will only allow admins to create new chatrooms.
18661 Otherwise anyone can create a room. The value @samp{"local"} restricts room
18662 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
18663 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
18664 restricts to service administrators only.
18665 Defaults to @samp{#f}.
18668 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
18669 Maximum number of history messages that will be sent to the member that has
18670 just joined the room.
18671 Defaults to @samp{20}.
18678 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
18679 External components use XEP-0114, which most standalone components
18680 support. To add an external component, you simply fill the hostname field. See
18681 @url{https://prosody.im/doc/components}.
18682 Defaults to @samp{()}.
18684 Available @code{ext-component-configuration} fields are:
18686 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:
18687 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
18688 Password which the component will use to log in.
18691 @deftypevr {@code{ext-component-configuration} parameter} string hostname
18692 Hostname of the component.
18697 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
18698 Port(s) Prosody listens on for component connections.
18699 Defaults to @samp{(5347)}.
18702 @deftypevr {@code{prosody-configuration} parameter} string component-interface
18703 Interface Prosody listens on for component connections.
18704 Defaults to @samp{"127.0.0.1"}.
18707 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
18708 Raw content that will be added to the configuration file.
18711 It could be that you just want to get a @code{prosody.cfg.lua}
18712 up and running. In that case, you can pass an
18713 @code{opaque-prosody-configuration} record as the value of
18714 @code{prosody-service-type}. As its name indicates, an opaque configuration
18715 does not have easy reflective capabilities.
18716 Available @code{opaque-prosody-configuration} fields are:
18718 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
18719 The prosody package.
18722 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
18723 The contents of the @code{prosody.cfg.lua} to use.
18726 For example, if your @code{prosody.cfg.lua} is just the empty
18727 string, you could instantiate a prosody service like this:
18730 (service prosody-service-type
18731 (opaque-prosody-configuration
18732 (prosody.cfg.lua "")))
18735 @c end of Prosody auto-generated documentation
18737 @subsubheading BitlBee Service
18739 @cindex IRC (Internet Relay Chat)
18740 @cindex IRC gateway
18741 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
18742 interface to a variety of messaging protocols such as XMPP.
18744 @defvr {Scheme Variable} bitlbee-service-type
18745 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
18746 gateway daemon. Its value is a @code{bitlbee-configuration} (see
18749 To have BitlBee listen on port 6667 on localhost, add this line to your
18753 (service bitlbee-service-type)
18757 @deftp {Data Type} bitlbee-configuration
18758 This is the configuration for BitlBee, with the following fields:
18761 @item @code{interface} (default: @code{"127.0.0.1"})
18762 @itemx @code{port} (default: @code{6667})
18763 Listen on the network interface corresponding to the IP address
18764 specified in @var{interface}, on @var{port}.
18766 When @var{interface} is @code{127.0.0.1}, only local clients can
18767 connect; when it is @code{0.0.0.0}, connections can come from any
18768 networking interface.
18770 @item @code{bitlbee} (default: @code{bitlbee})
18771 The BitlBee package to use.
18773 @item @code{plugins} (default: @code{'()})
18774 List of plugin packages to use---e.g., @code{bitlbee-discord}.
18776 @item @code{extra-settings} (default: @code{""})
18777 Configuration snippet added as-is to the BitlBee configuration file.
18781 @subsubheading Quassel Service
18783 @cindex IRC (Internet Relay Chat)
18784 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
18785 meaning that one or more clients can attach to and detach from the
18788 @defvr {Scheme Variable} quassel-service-type
18789 This is the service type for the @url{https://quassel-irc.org/,Quassel}
18790 IRC backend daemon. Its value is a @code{quassel-configuration}
18794 @deftp {Data Type} quassel-configuration
18795 This is the configuration for Quassel, with the following fields:
18798 @item @code{quassel} (default: @code{quassel})
18799 The Quassel package to use.
18801 @item @code{interface} (default: @code{"::,0.0.0.0"})
18802 @item @code{port} (default: @code{4242})
18803 Listen on the network interface(s) corresponding to the IPv4 or IPv6
18804 interfaces specified in the comma delimited @var{interface}, on
18807 @item @code{loglevel} (default: @code{"Info"})
18808 The level of logging desired. Accepted values are Debug, Info, Warning
18813 @node Telephony Services
18814 @subsection Telephony Services
18816 @cindex Murmur (VoIP server)
18817 @cindex VoIP server
18818 This section describes how to set up and run a Murmur server. Murmur is
18819 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
18822 @deftp {Data Type} murmur-configuration
18823 The service type for the Murmur server. An example configuration can
18827 (service murmur-service-type
18828 (murmur-configuration
18830 "Welcome to this Mumble server running on Guix!")
18831 (cert-required? #t) ;disallow text password logins
18832 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
18833 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
18836 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
18837 password with the command that is printed during the activation phase.
18839 It is recommended to register a normal Mumble user account
18840 and grant it admin or moderator rights.
18841 You can use the @code{mumble} client to
18842 login as new normal user, register yourself, and log out.
18843 For the next step login with the name @code{SuperUser} use
18844 the @code{SuperUser} password that you set previously,
18845 and grant your newly registered mumble user administrator or moderator
18846 rights and create some channels.
18848 Available @code{murmur-configuration} fields are:
18851 @item @code{package} (default: @code{mumble})
18852 Package that contains @code{bin/murmurd}.
18854 @item @code{user} (default: @code{"murmur"})
18855 User who will run the Murmur server.
18857 @item @code{group} (default: @code{"murmur"})
18858 Group of the user who will run the murmur server.
18860 @item @code{port} (default: @code{64738})
18861 Port on which the server will listen.
18863 @item @code{welcome-text} (default: @code{""})
18864 Welcome text sent to clients when they connect.
18866 @item @code{server-password} (default: @code{""})
18867 Password the clients have to enter in order to connect.
18869 @item @code{max-users} (default: @code{100})
18870 Maximum of users that can be connected to the server at once.
18872 @item @code{max-user-bandwidth} (default: @code{#f})
18873 Maximum voice traffic a user can send per second.
18875 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
18876 File name of the sqlite database.
18877 The service's user will become the owner of the directory.
18879 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
18880 File name of the log file.
18881 The service's user will become the owner of the directory.
18883 @item @code{autoban-attempts} (default: @code{10})
18884 Maximum number of logins a user can make in @code{autoban-timeframe}
18885 without getting auto banned for @code{autoban-time}.
18887 @item @code{autoban-timeframe} (default: @code{120})
18888 Timeframe for autoban in seconds.
18890 @item @code{autoban-time} (default: @code{300})
18891 Amount of time in seconds for which a client gets banned
18892 when violating the autoban limits.
18894 @item @code{opus-threshold} (default: @code{100})
18895 Percentage of clients that need to support opus
18896 before switching over to opus audio codec.
18898 @item @code{channel-nesting-limit} (default: @code{10})
18899 How deep channels can be nested at maximum.
18901 @item @code{channelname-regex} (default: @code{#f})
18902 A string in form of a Qt regular expression that channel names must conform to.
18904 @item @code{username-regex} (default: @code{#f})
18905 A string in form of a Qt regular expression that user names must conform to.
18907 @item @code{text-message-length} (default: @code{5000})
18908 Maximum size in bytes that a user can send in one text chat message.
18910 @item @code{image-message-length} (default: @code{(* 128 1024)})
18911 Maximum size in bytes that a user can send in one image message.
18913 @item @code{cert-required?} (default: @code{#f})
18914 If it is set to @code{#t} clients that use weak password authentication
18915 will not be accepted. Users must have completed the certificate wizard to join.
18917 @item @code{remember-channel?} (default: @code{#f})
18918 Should murmur remember the last channel each user was in when they disconnected
18919 and put them into the remembered channel when they rejoin.
18921 @item @code{allow-html?} (default: @code{#f})
18922 Should html be allowed in text messages, user comments, and channel descriptions.
18924 @item @code{allow-ping?} (default: @code{#f})
18925 Setting to true exposes the current user count, the maximum user count, and
18926 the server's maximum bandwidth per client to unauthenticated users. In the
18927 Mumble client, this information is shown in the Connect dialog.
18929 Disabling this setting will prevent public listing of the server.
18931 @item @code{bonjour?} (default: @code{#f})
18932 Should the server advertise itself in the local network through the bonjour protocol.
18934 @item @code{send-version?} (default: @code{#f})
18935 Should the murmur server version be exposed in ping requests.
18937 @item @code{log-days} (default: @code{31})
18938 Murmur also stores logs in the database, which are accessible via RPC.
18939 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
18940 or -1 to disable logging to the database.
18942 @item @code{obfuscate-ips?} (default: @code{#t})
18943 Should logged ips be obfuscated to protect the privacy of users.
18945 @item @code{ssl-cert} (default: @code{#f})
18946 File name of the SSL/TLS certificate used for encrypted connections.
18949 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
18951 @item @code{ssl-key} (default: @code{#f})
18952 Filepath to the ssl private key used for encrypted connections.
18954 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
18957 @item @code{ssl-dh-params} (default: @code{#f})
18958 File name of a PEM-encoded file with Diffie-Hellman parameters
18959 for the SSL/TLS encryption. Alternatively you set it to
18960 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
18961 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
18963 @item @code{ssl-ciphers} (default: @code{#f})
18964 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
18967 This option is specified using
18968 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
18969 OpenSSL cipher list notation}.
18971 It is recommended that you try your cipher string using 'openssl ciphers <string>'
18972 before setting it here, to get a feel for which cipher suites you will get.
18973 After setting this option, it is recommend that you inspect your Murmur log
18974 to ensure that Murmur is using the cipher suites that you expected it to.
18976 Note: Changing this option may impact the backwards compatibility of your
18977 Murmur server, and can remove the ability for older Mumble clients to be able
18980 @item @code{public-registration} (default: @code{#f})
18981 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
18983 You can optionally register your server in the public server list that the
18984 @code{mumble} client shows on startup.
18985 You cannot register your server if you have set a @code{server-password},
18986 or set @code{allow-ping} to @code{#f}.
18988 It might take a few hours until it shows up in the public list.
18990 @item @code{file} (default: @code{#f})
18991 Optional alternative override for this configuration.
18995 @deftp {Data Type} murmur-public-registration-configuration
18996 Configuration for public registration of a murmur service.
19000 This is a display name for your server. Not to be confused with the hostname.
19002 @item @code{password}
19003 A password to identify your registration.
19004 Subsequent updates will need the same password. Don't lose your password.
19007 This should be a @code{http://} or @code{https://} link to your web
19010 @item @code{hostname} (default: @code{#f})
19011 By default your server will be listed by its IP address.
19012 If it is set your server will be linked by this host name instead.
19018 @node Monitoring Services
19019 @subsection Monitoring Services
19021 @subsubheading Tailon Service
19023 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
19024 viewing and searching log files.
19026 The following example will configure the service with default values.
19027 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
19030 (service tailon-service-type)
19033 The following example customises more of the Tailon configuration,
19034 adding @command{sed} to the list of allowed commands.
19037 (service tailon-service-type
19038 (tailon-configuration
19040 (tailon-configuration-file
19041 (allowed-commands '("tail" "grep" "awk" "sed"))))))
19045 @deftp {Data Type} tailon-configuration
19046 Data type representing the configuration of Tailon.
19047 This type has the following parameters:
19050 @item @code{config-file} (default: @code{(tailon-configuration-file)})
19051 The configuration file to use for Tailon. This can be set to a
19052 @dfn{tailon-configuration-file} record value, or any gexp
19053 (@pxref{G-Expressions}).
19055 For example, to instead use a local file, the @code{local-file} function
19059 (service tailon-service-type
19060 (tailon-configuration
19061 (config-file (local-file "./my-tailon.conf"))))
19064 @item @code{package} (default: @code{tailon})
19065 The tailon package to use.
19070 @deftp {Data Type} tailon-configuration-file
19071 Data type representing the configuration options for Tailon.
19072 This type has the following parameters:
19075 @item @code{files} (default: @code{(list "/var/log")})
19076 List of files to display. The list can include strings for a single file
19077 or directory, or a list, where the first item is the name of a
19078 subsection, and the remaining items are the files or directories in that
19081 @item @code{bind} (default: @code{"localhost:8080"})
19082 Address and port to which Tailon should bind on.
19084 @item @code{relative-root} (default: @code{#f})
19085 URL path to use for Tailon, set to @code{#f} to not use a path.
19087 @item @code{allow-transfers?} (default: @code{#t})
19088 Allow downloading the log files in the web interface.
19090 @item @code{follow-names?} (default: @code{#t})
19091 Allow tailing of not-yet existent files.
19093 @item @code{tail-lines} (default: @code{200})
19094 Number of lines to read initially from each file.
19096 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
19097 Commands to allow running. By default, @code{sed} is disabled.
19099 @item @code{debug?} (default: @code{#f})
19100 Set @code{debug?} to @code{#t} to show debug messages.
19102 @item @code{wrap-lines} (default: @code{#t})
19103 Initial line wrapping state in the web interface. Set to @code{#t} to
19104 initially wrap lines (the default), or to @code{#f} to initially not
19107 @item @code{http-auth} (default: @code{#f})
19108 HTTP authentication type to use. Set to @code{#f} to disable
19109 authentication (the default). Supported values are @code{"digest"} or
19112 @item @code{users} (default: @code{#f})
19113 If HTTP authentication is enabled (see @code{http-auth}), access will be
19114 restricted to the credentials provided here. To configure users, use a
19115 list of pairs, where the first element of the pair is the username, and
19116 the 2nd element of the pair is the password.
19119 (tailon-configuration-file
19120 (http-auth "basic")
19121 (users '(("user1" . "password1")
19122 ("user2" . "password2"))))
19129 @subsubheading Darkstat Service
19131 Darkstat is a packet sniffer that captures network traffic, calculates
19132 statistics about usage, and serves reports over HTTP.
19134 @defvar {Scheme Variable} darkstat-service-type
19135 This is the service type for the
19136 @uref{https://unix4lyfe.org/darkstat/, darkstat}
19137 service, its value must be a @code{darkstat-configuration} record as in
19141 (service darkstat-service-type
19142 (darkstat-configuration
19143 (interface "eno1")))
19147 @deftp {Data Type} darkstat-configuration
19148 Data type representing the configuration of @command{darkstat}.
19151 @item @code{package} (default: @code{darkstat})
19152 The darkstat package to use.
19154 @item @code{interface}
19155 Capture traffic on the specified network interface.
19157 @item @code{port} (default: @code{"667"})
19158 Bind the web interface to the specified port.
19160 @item @code{bind-address} (default: @code{"127.0.0.1"})
19161 Bind the web interface to the specified address.
19163 @item @code{base} (default: @code{"/"})
19164 Specify the path of the base URL. This can be useful if
19165 @command{darkstat} is accessed via a reverse proxy.
19170 @subsubheading Prometheus Node Exporter Service
19172 @cindex prometheus-node-exporter
19173 The Prometheus ``node exporter'' makes hardware and operating system statistics
19174 provided by the Linux kernel available for the Prometheus monitoring system.
19175 This service should be deployed on all physical nodes and virtual machines,
19176 where monitoring these statistics is desirable.
19178 @defvar {Scheme variable} prometheus-node-exporter-service-type
19179 This is the service type for the
19180 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
19181 service, its value must be a @code{prometheus-node-exporter-configuration}
19182 record as in this example:
19185 (service prometheus-node-exporter-service-type
19186 (prometheus-node-exporter-configuration
19187 (web-listen-address ":9100")))
19191 @deftp {Data Type} prometheus-node-exporter-configuration
19192 Data type representing the configuration of @command{node_exporter}.
19195 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
19196 The prometheus-node-exporter package to use.
19198 @item @code{web-listen-address} (default: @code{":9100"})
19199 Bind the web interface to the specified address.
19204 @subsubheading Zabbix server
19205 @cindex zabbix zabbix-server
19206 Zabbix provides monitoring metrics, among others network utilization, CPU load
19207 and disk space consumption:
19210 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
19211 @item Auto-discovery of servers and network devices and interfaces.
19212 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
19213 @item Distributed monitoring with centralized web administration.
19214 @item Native high performance agents.
19215 @item SLA, and ITIL KPI metrics on reporting.
19216 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
19217 @item Remote command execution through Zabbix proxies.
19220 @c %start of fragment
19222 Available @code{zabbix-server-configuration} fields are:
19224 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
19225 The zabbix-server package.
19229 @deftypevr {@code{zabbix-server-configuration} parameter} string user
19230 User who will run the Zabbix server.
19232 Defaults to @samp{"zabbix"}.
19236 @deftypevr {@code{zabbix-server-configuration} parameter} group group
19237 Group who will run the Zabbix server.
19239 Defaults to @samp{"zabbix"}.
19243 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
19244 Database host name.
19246 Defaults to @samp{"127.0.0.1"}.
19250 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
19253 Defaults to @samp{"zabbix"}.
19257 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
19260 Defaults to @samp{"zabbix"}.
19264 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
19265 Database password. Please, use @code{include-files} with
19266 @code{DBPassword=SECRET} inside a specified file instead.
19268 Defaults to @samp{""}.
19272 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
19275 Defaults to @samp{5432}.
19279 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
19280 Specifies where log messages are written to:
19284 @code{system} - syslog.
19287 @code{file} - file specified with @code{log-file} parameter.
19290 @code{console} - standard output.
19294 Defaults to @samp{""}.
19298 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
19299 Log file name for @code{log-type} @code{file} parameter.
19301 Defaults to @samp{"/var/log/zabbix/server.log"}.
19305 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
19308 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
19312 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
19313 The location of certificate authority (CA) files for SSL server
19314 certificate verification.
19316 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
19320 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
19321 Location of SSL client certificates.
19323 Defaults to @samp{"/etc/ssl/certs"}.
19327 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
19328 Extra options will be appended to Zabbix server configuration file.
19330 Defaults to @samp{""}.
19334 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
19335 You may include individual files or all files in a directory in the
19336 configuration file.
19338 Defaults to @samp{()}.
19342 @c %end of fragment
19344 @subsubheading Zabbix agent
19345 @cindex zabbix zabbix-agent
19347 Zabbix agent gathers information for Zabbix server.
19349 @c %start of fragment
19351 Available @code{zabbix-agent-configuration} fields are:
19353 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
19354 The zabbix-agent package.
19358 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
19359 User who will run the Zabbix agent.
19361 Defaults to @samp{"zabbix"}.
19365 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
19366 Group who will run the Zabbix agent.
19368 Defaults to @samp{"zabbix"}.
19372 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
19373 Unique, case sensitive hostname which is required for active checks and
19374 must match hostname as configured on the server.
19376 Defaults to @samp{"Zabbix server"}.
19380 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
19381 Specifies where log messages are written to:
19385 @code{system} - syslog.
19388 @code{file} - file specified with @code{log-file} parameter.
19391 @code{console} - standard output.
19395 Defaults to @samp{""}.
19399 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
19400 Log file name for @code{log-type} @code{file} parameter.
19402 Defaults to @samp{"/var/log/zabbix/agent.log"}.
19406 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
19409 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
19413 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
19414 List of IP addresses, optionally in CIDR notation, or hostnames of
19415 Zabbix servers and Zabbix proxies. Incoming connections will be
19416 accepted only from the hosts listed here.
19418 Defaults to @samp{("127.0.0.1")}.
19422 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
19423 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
19424 proxies for active checks. If port is not specified, default port is
19425 used. If this parameter is not specified, active checks are disabled.
19427 Defaults to @samp{("127.0.0.1")}.
19431 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
19432 Extra options will be appended to Zabbix server configuration file.
19434 Defaults to @samp{""}.
19438 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
19439 You may include individual files or all files in a directory in the
19440 configuration file.
19442 Defaults to @samp{()}.
19446 @c %end of fragment
19448 @subsubheading Zabbix front-end
19449 @cindex zabbix zabbix-front-end
19451 This service provides a WEB interface to Zabbix server.
19453 @c %start of fragment
19455 Available @code{zabbix-front-end-configuration} fields are:
19457 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
19458 NGINX configuration.
19462 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
19463 Database host name.
19465 Defaults to @samp{"localhost"}.
19469 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
19472 Defaults to @samp{5432}.
19476 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
19479 Defaults to @samp{"zabbix"}.
19483 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
19486 Defaults to @samp{"zabbix"}.
19490 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
19491 Database password. Please, use @code{db-secret-file} instead.
19493 Defaults to @samp{""}.
19497 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
19498 Secret file which will be appended to @file{zabbix.conf.php} file. This
19499 file contains credentials for use by Zabbix front-end. You are expected
19500 to create it manually.
19502 Defaults to @samp{""}.
19506 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
19507 Zabbix server hostname.
19509 Defaults to @samp{"localhost"}.
19513 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
19514 Zabbix server port.
19516 Defaults to @samp{10051}.
19521 @c %end of fragment
19523 @node Kerberos Services
19524 @subsection Kerberos Services
19527 The @code{(gnu services kerberos)} module provides services relating to
19528 the authentication protocol @dfn{Kerberos}.
19530 @subsubheading Krb5 Service
19532 Programs using a Kerberos client library normally
19533 expect a configuration file in @file{/etc/krb5.conf}.
19534 This service generates such a file from a definition provided in the
19535 operating system declaration.
19536 It does not cause any daemon to be started.
19538 No ``keytab'' files are provided by this service---you must explicitly create them.
19539 This service is known to work with the MIT client library, @code{mit-krb5}.
19540 Other implementations have not been tested.
19542 @defvr {Scheme Variable} krb5-service-type
19543 A service type for Kerberos 5 clients.
19547 Here is an example of its use:
19549 (service krb5-service-type
19550 (krb5-configuration
19551 (default-realm "EXAMPLE.COM")
19552 (allow-weak-crypto? #t)
19555 (name "EXAMPLE.COM")
19556 (admin-server "groucho.example.com")
19557 (kdc "karl.example.com"))
19560 (admin-server "kerb-admin.argrx.edu")
19561 (kdc "keys.argrx.edu"))))))
19565 This example provides a Kerberos@tie{}5 client configuration which:
19567 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
19568 of which have distinct administration servers and key distribution centers;
19569 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
19570 specified by clients;
19571 @item Accepts services which only support encryption types known to be weak.
19574 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
19575 Only the most commonly used ones are described here.
19576 For a full list, and more detailed explanation of each, see the MIT
19577 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
19581 @deftp {Data Type} krb5-realm
19582 @cindex realm, kerberos
19585 This field is a string identifying the name of the realm.
19586 A common convention is to use the fully qualified DNS name of your organization,
19587 converted to upper case.
19589 @item @code{admin-server}
19590 This field is a string identifying the host where the administration server is
19594 This field is a string identifying the key distribution center
19599 @deftp {Data Type} krb5-configuration
19602 @item @code{allow-weak-crypto?} (default: @code{#f})
19603 If this flag is @code{#t} then services which only offer encryption algorithms
19604 known to be weak will be accepted.
19606 @item @code{default-realm} (default: @code{#f})
19607 This field should be a string identifying the default Kerberos
19608 realm for the client.
19609 You should set this field to the name of your Kerberos realm.
19610 If this value is @code{#f}
19611 then a realm must be specified with every Kerberos principal when invoking programs
19612 such as @command{kinit}.
19614 @item @code{realms}
19615 This should be a non-empty list of @code{krb5-realm} objects, which clients may
19617 Normally, one of them will have a @code{name} field matching the @code{default-realm}
19623 @subsubheading PAM krb5 Service
19626 The @code{pam-krb5} service allows for login authentication and password
19627 management via Kerberos.
19628 You will need this service if you want PAM enabled applications to authenticate
19629 users using Kerberos.
19631 @defvr {Scheme Variable} pam-krb5-service-type
19632 A service type for the Kerberos 5 PAM module.
19635 @deftp {Data Type} pam-krb5-configuration
19636 Data type representing the configuration of the Kerberos 5 PAM module.
19637 This type has the following parameters:
19639 @item @code{pam-krb5} (default: @code{pam-krb5})
19640 The pam-krb5 package to use.
19642 @item @code{minimum-uid} (default: @code{1000})
19643 The smallest user ID for which Kerberos authentications should be attempted.
19644 Local accounts with lower values will silently fail to authenticate.
19649 @node LDAP Services
19650 @subsection LDAP Services
19652 @cindex nslcd, LDAP service
19654 The @code{(gnu services authentication)} module provides the
19655 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
19656 server. In addition to configuring the service itself, you may want to add
19657 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
19658 Switch} for detailed information.
19660 Here is a simple operating system declaration with a default configuration of
19661 the @code{nslcd-service-type} and a Name Service Switch configuration that
19662 consults the @code{ldap} name service last:
19665 (use-service-modules authentication)
19666 (use-modules (gnu system nss))
19672 (service nslcd-service-type)
19673 (service dhcp-client-service-type)
19675 (name-service-switch
19676 (let ((services (list (name-service (name "db"))
19677 (name-service (name "files"))
19678 (name-service (name "ldap")))))
19679 (name-service-switch
19680 (inherit %mdns-host-lookup-nss)
19681 (password services)
19684 (netgroup services)
19685 (gshadow services)))))
19688 @c %start of generated documentation for nslcd-configuration
19690 Available @code{nslcd-configuration} fields are:
19692 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
19693 The @code{nss-pam-ldapd} package to use.
19697 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
19698 The number of threads to start that can handle requests and perform LDAP
19699 queries. Each thread opens a separate connection to the LDAP server.
19700 The default is to start 5 threads.
19702 Defaults to @samp{disabled}.
19706 @deftypevr {@code{nslcd-configuration} parameter} string uid
19707 This specifies the user id with which the daemon should be run.
19709 Defaults to @samp{"nslcd"}.
19713 @deftypevr {@code{nslcd-configuration} parameter} string gid
19714 This specifies the group id with which the daemon should be run.
19716 Defaults to @samp{"nslcd"}.
19720 @deftypevr {@code{nslcd-configuration} parameter} log-option log
19721 This option controls the way logging is done via a list containing
19722 SCHEME and LEVEL. The SCHEME argument may either be the symbols
19723 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
19724 argument is optional and specifies the log level. The log level may be
19725 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
19726 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
19727 specified log level or higher are logged.
19729 Defaults to @samp{("/var/log/nslcd" info)}.
19733 @deftypevr {@code{nslcd-configuration} parameter} list uri
19734 The list of LDAP server URIs. Normally, only the first server will be
19735 used with the following servers as fall-back.
19737 Defaults to @samp{("ldap://localhost:389/")}.
19741 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
19742 The version of the LDAP protocol to use. The default is to use the
19743 maximum version supported by the LDAP library.
19745 Defaults to @samp{disabled}.
19749 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
19750 Specifies the distinguished name with which to bind to the directory
19751 server for lookups. The default is to bind anonymously.
19753 Defaults to @samp{disabled}.
19757 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
19758 Specifies the credentials with which to bind. This option is only
19759 applicable when used with binddn.
19761 Defaults to @samp{disabled}.
19765 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
19766 Specifies the distinguished name to use when the root user tries to
19767 modify a user's password using the PAM module.
19769 Defaults to @samp{disabled}.
19773 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
19774 Specifies the credentials with which to bind if the root user tries to
19775 change a user's password. This option is only applicable when used with
19778 Defaults to @samp{disabled}.
19782 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
19783 Specifies the SASL mechanism to be used when performing SASL
19786 Defaults to @samp{disabled}.
19790 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
19791 Specifies the SASL realm to be used when performing SASL authentication.
19793 Defaults to @samp{disabled}.
19797 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
19798 Specifies the authentication identity to be used when performing SASL
19801 Defaults to @samp{disabled}.
19805 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
19806 Specifies the authorization identity to be used when performing SASL
19809 Defaults to @samp{disabled}.
19813 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
19814 Determines whether the LDAP server host name should be canonicalised. If
19815 this is enabled the LDAP library will do a reverse host name lookup. By
19816 default, it is left up to the LDAP library whether this check is
19819 Defaults to @samp{disabled}.
19823 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
19824 Set the name for the GSS-API Kerberos credentials cache.
19826 Defaults to @samp{disabled}.
19830 @deftypevr {@code{nslcd-configuration} parameter} string base
19831 The directory search base.
19833 Defaults to @samp{"dc=example,dc=com"}.
19837 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
19838 Specifies the search scope (subtree, onelevel, base or children). The
19839 default scope is subtree; base scope is almost never useful for name
19840 service lookups; children scope is not supported on all servers.
19842 Defaults to @samp{(subtree)}.
19846 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
19847 Specifies the policy for dereferencing aliases. The default policy is
19848 to never dereference aliases.
19850 Defaults to @samp{disabled}.
19854 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
19855 Specifies whether automatic referral chasing should be enabled. The
19856 default behaviour is to chase referrals.
19858 Defaults to @samp{disabled}.
19862 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
19863 This option allows for custom attributes to be looked up instead of the
19864 default RFC 2307 attributes. It is a list of maps, each consisting of
19865 the name of a map, the RFC 2307 attribute to match and the query
19866 expression for the attribute as it is available in the directory.
19868 Defaults to @samp{()}.
19872 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
19873 A list of filters consisting of the name of a map to which the filter
19874 applies and an LDAP search filter expression.
19876 Defaults to @samp{()}.
19880 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
19881 Specifies the time limit in seconds to use when connecting to the
19882 directory server. The default value is 10 seconds.
19884 Defaults to @samp{disabled}.
19888 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
19889 Specifies the time limit (in seconds) to wait for a response from the
19890 LDAP server. A value of zero, which is the default, is to wait
19891 indefinitely for searches to be completed.
19893 Defaults to @samp{disabled}.
19897 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
19898 Specifies the period if inactivity (in seconds) after which the con‐
19899 nection to the LDAP server will be closed. The default is not to time
19902 Defaults to @samp{disabled}.
19906 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
19907 Specifies the number of seconds to sleep when connecting to all LDAP
19908 servers fails. By default one second is waited between the first
19909 failure and the first retry.
19911 Defaults to @samp{disabled}.
19915 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
19916 Specifies the time after which the LDAP server is considered to be
19917 permanently unavailable. Once this time is reached retries will be done
19918 only once per this time period. The default value is 10 seconds.
19920 Defaults to @samp{disabled}.
19924 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
19925 Specifies whether to use SSL/TLS or not (the default is not to). If
19926 'start-tls is specified then StartTLS is used rather than raw LDAP over
19929 Defaults to @samp{disabled}.
19933 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
19934 Specifies what checks to perform on a server-supplied certificate. The
19935 meaning of the values is described in the ldap.conf(5) manual page.
19937 Defaults to @samp{disabled}.
19941 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
19942 Specifies the directory containing X.509 certificates for peer authen‐
19943 tication. This parameter is ignored when using GnuTLS.
19945 Defaults to @samp{disabled}.
19949 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
19950 Specifies the path to the X.509 certificate for peer authentication.
19952 Defaults to @samp{disabled}.
19956 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
19957 Specifies the path to an entropy source. This parameter is ignored when
19960 Defaults to @samp{disabled}.
19964 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
19965 Specifies the ciphers to use for TLS as a string.
19967 Defaults to @samp{disabled}.
19971 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
19972 Specifies the path to the file containing the local certificate for
19973 client TLS authentication.
19975 Defaults to @samp{disabled}.
19979 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
19980 Specifies the path to the file containing the private key for client TLS
19983 Defaults to @samp{disabled}.
19987 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
19988 Set this to a number greater than 0 to request paged results from the
19989 LDAP server in accordance with RFC2696. The default (0) is to not
19990 request paged results.
19992 Defaults to @samp{disabled}.
19996 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
19997 This option prevents group membership lookups through LDAP for the
19998 specified users. Alternatively, the value 'all-local may be used. With
19999 that value nslcd builds a full list of non-LDAP users on startup.
20001 Defaults to @samp{disabled}.
20005 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
20006 This option ensures that LDAP users with a numeric user id lower than
20007 the specified value are ignored.
20009 Defaults to @samp{disabled}.
20013 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
20014 This option specifies an offset that is added to all LDAP numeric user
20015 ids. This can be used to avoid user id collisions with local users.
20017 Defaults to @samp{disabled}.
20021 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
20022 This option specifies an offset that is added to all LDAP numeric group
20023 ids. This can be used to avoid user id collisions with local groups.
20025 Defaults to @samp{disabled}.
20029 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
20030 If this option is set, the member attribute of a group may point to
20031 another group. Members of nested groups are also returned in the higher
20032 level group and parent groups are returned when finding groups for a
20033 specific user. The default is not to perform extra searches for nested
20036 Defaults to @samp{disabled}.
20040 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
20041 If this option is set, the group member list is not retrieved when
20042 looking up groups. Lookups for finding which groups a user belongs to
20043 will remain functional so the user will likely still get the correct
20044 groups assigned on login.
20046 Defaults to @samp{disabled}.
20050 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
20051 If this option is set, functions which cause all user/group entries to
20052 be loaded from the directory will not succeed in doing so. This can
20053 dramatically reduce LDAP server load in situations where there are a
20054 great number of users and/or groups. This option is not recommended for
20055 most configurations.
20057 Defaults to @samp{disabled}.
20061 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
20062 This option can be used to specify how user and group names are verified
20063 within the system. This pattern is used to check all user and group
20064 names that are requested and returned from LDAP.
20066 Defaults to @samp{disabled}.
20070 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
20071 This specifies whether or not to perform searches using case-insensitive
20072 matching. Enabling this could open up the system to authorization
20073 bypass vulnerabilities and introduce nscd cache poisoning
20074 vulnerabilities which allow denial of service.
20076 Defaults to @samp{disabled}.
20080 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
20081 This option specifies whether password policy controls are requested and
20082 handled from the LDAP server when performing user authentication.
20084 Defaults to @samp{disabled}.
20088 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
20089 By default nslcd performs an LDAP search with the user's credentials
20090 after BIND (authentication) to ensure that the BIND operation was
20091 successful. The default search is a simple check to see if the user's
20092 DN exists. A search filter can be specified that will be used instead.
20093 It should return at least one entry.
20095 Defaults to @samp{disabled}.
20099 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
20100 This option allows flexible fine tuning of the authorisation check that
20101 should be performed. The search filter specified is executed and if any
20102 entries match, access is granted, otherwise access is denied.
20104 Defaults to @samp{disabled}.
20108 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
20109 If this option is set password modification using pam_ldap will be
20110 denied and the specified message will be presented to the user instead.
20111 The message can be used to direct the user to an alternative means of
20112 changing their password.
20114 Defaults to @samp{disabled}.
20118 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
20119 List of pam service names for which LDAP authentication should suffice.
20121 Defaults to @samp{()}.
20125 @c %end of generated documentation for nslcd-configuration
20129 @subsection Web Services
20134 The @code{(gnu services web)} module provides the Apache HTTP Server,
20135 the nginx web server, and also a fastcgi wrapper daemon.
20137 @subsubheading Apache HTTP Server
20139 @deffn {Scheme Variable} httpd-service-type
20140 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
20141 (@dfn{httpd}). The value for this service type is a
20142 @code{httpd-configuration} record.
20144 A simple example configuration is given below.
20147 (service httpd-service-type
20148 (httpd-configuration
20151 (server-name "www.example.com")
20152 (document-root "/srv/http/www.example.com")))))
20155 Other services can also extend the @code{httpd-service-type} to add to
20159 (simple-service 'www.example.com-server httpd-service-type
20163 (list (string-join '("ServerName www.example.com"
20164 "DocumentRoot /srv/http/www.example.com")
20169 The details for the @code{httpd-configuration}, @code{httpd-module},
20170 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
20173 @deffn {Data Type} httpd-configuration
20174 This data type represents the configuration for the httpd service.
20177 @item @code{package} (default: @code{httpd})
20178 The httpd package to use.
20180 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20181 The pid file used by the shepherd-service.
20183 @item @code{config} (default: @code{(httpd-config-file)})
20184 The configuration file to use with the httpd service. The default value
20185 is a @code{httpd-config-file} record, but this can also be a different
20186 G-expression that generates a file, for example a @code{plain-file}. A
20187 file outside of the store can also be specified through a string.
20192 @deffn {Data Type} httpd-module
20193 This data type represents a module for the httpd service.
20197 The name of the module.
20200 The file for the module. This can be relative to the httpd package being
20201 used, the absolute location of a file, or a G-expression for a file
20202 within the store, for example @code{(file-append mod-wsgi
20203 "/modules/mod_wsgi.so")}.
20208 @defvr {Scheme Variable} %default-httpd-modules
20209 A default list of @code{httpd-module} objects.
20212 @deffn {Data Type} httpd-config-file
20213 This data type represents a configuration file for the httpd service.
20216 @item @code{modules} (default: @code{%default-httpd-modules})
20217 The modules to load. Additional modules can be added here, or loaded by
20218 additional configuration.
20220 For example, in order to handle requests for PHP files, you can use Apache’s
20221 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
20224 (service httpd-service-type
20225 (httpd-configuration
20230 (name "proxy_module")
20231 (file "modules/mod_proxy.so"))
20233 (name "proxy_fcgi_module")
20234 (file "modules/mod_proxy_fcgi.so"))
20235 %default-httpd-modules))
20236 (extra-config (list "\
20237 <FilesMatch \\.php$>
20238 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
20239 </FilesMatch>"))))))
20240 (service php-fpm-service-type
20241 (php-fpm-configuration
20242 (socket "/var/run/php-fpm.sock")
20243 (socket-group "httpd")))
20246 @item @code{server-root} (default: @code{httpd})
20247 The @code{ServerRoot} in the configuration file, defaults to the httpd
20248 package. Directives including @code{Include} and @code{LoadModule} are
20249 taken as relative to the server root.
20251 @item @code{server-name} (default: @code{#f})
20252 The @code{ServerName} in the configuration file, used to specify the
20253 request scheme, hostname and port that the server uses to identify
20256 This doesn't need to be set in the server config, and can be specified
20257 in virtual hosts. The default is @code{#f} to not specify a
20260 @item @code{document-root} (default: @code{"/srv/http"})
20261 The @code{DocumentRoot} from which files will be served.
20263 @item @code{listen} (default: @code{'("80")})
20264 The list of values for the @code{Listen} directives in the config
20265 file. The value should be a list of strings, when each string can
20266 specify the port number to listen on, and optionally the IP address and
20269 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20270 The @code{PidFile} to use. This should match the @code{pid-file} set in
20271 the @code{httpd-configuration} so that the Shepherd service is
20272 configured correctly.
20274 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
20275 The @code{ErrorLog} to which the server will log errors.
20277 @item @code{user} (default: @code{"httpd"})
20278 The @code{User} which the server will answer requests as.
20280 @item @code{group} (default: @code{"httpd"})
20281 The @code{Group} which the server will answer requests as.
20283 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
20284 A flat list of strings and G-expressions which will be added to the end
20285 of the configuration file.
20287 Any values which the service is extended with will be appended to this
20293 @deffn {Data Type} httpd-virtualhost
20294 This data type represents a virtualhost configuration block for the httpd service.
20296 These should be added to the extra-config for the httpd-service.
20299 (simple-service 'www.example.com-server httpd-service-type
20303 (list (string-join '("ServerName www.example.com"
20304 "DocumentRoot /srv/http/www.example.com")
20309 @item @code{addresses-and-ports}
20310 The addresses and ports for the @code{VirtualHost} directive.
20312 @item @code{contents}
20313 The contents of the @code{VirtualHost} directive, this should be a list
20314 of strings and G-expressions.
20319 @subsubheading NGINX
20321 @deffn {Scheme Variable} nginx-service-type
20322 Service type for the @uref{https://nginx.org/,NGinx} web server. The
20323 value for this service type is a @code{<nginx-configuration>} record.
20325 A simple example configuration is given below.
20328 (service nginx-service-type
20329 (nginx-configuration
20331 (list (nginx-server-configuration
20332 (server-name '("www.example.com"))
20333 (root "/srv/http/www.example.com"))))))
20336 In addition to adding server blocks to the service configuration
20337 directly, this service can be extended by other services to add server
20338 blocks, as in this example:
20341 (simple-service 'my-extra-server nginx-service-type
20342 (list (nginx-server-configuration
20343 (root "/srv/http/extra-website")
20344 (try-files (list "$uri" "$uri/index.html")))))
20348 At startup, @command{nginx} has not yet read its configuration file, so
20349 it uses a default file to log error messages. If it fails to load its
20350 configuration file, that is where error messages are logged. After the
20351 configuration file is loaded, the default error log file changes as per
20352 configuration. In our case, startup error messages can be found in
20353 @file{/var/run/nginx/logs/error.log}, and after configuration in
20354 @file{/var/log/nginx/error.log}. The second location can be changed
20355 with the @var{log-directory} configuration option.
20357 @deffn {Data Type} nginx-configuration
20358 This data type represents the configuration for NGinx. Some
20359 configuration can be done through this and the other provided record
20360 types, or alternatively, a config file can be provided.
20363 @item @code{nginx} (default: @code{nginx})
20364 The nginx package to use.
20366 @item @code{log-directory} (default: @code{"/var/log/nginx"})
20367 The directory to which NGinx will write log files.
20369 @item @code{run-directory} (default: @code{"/var/run/nginx"})
20370 The directory in which NGinx will create a pid file, and write temporary
20373 @item @code{server-blocks} (default: @code{'()})
20374 A list of @dfn{server blocks} to create in the generated configuration
20375 file, the elements should be of type
20376 @code{<nginx-server-configuration>}.
20378 The following example would setup NGinx to serve @code{www.example.com}
20379 from the @code{/srv/http/www.example.com} directory, without using
20382 (service nginx-service-type
20383 (nginx-configuration
20385 (list (nginx-server-configuration
20386 (server-name '("www.example.com"))
20387 (root "/srv/http/www.example.com"))))))
20390 @item @code{upstream-blocks} (default: @code{'()})
20391 A list of @dfn{upstream blocks} to create in the generated configuration
20392 file, the elements should be of type
20393 @code{<nginx-upstream-configuration>}.
20395 Configuring upstreams through the @code{upstream-blocks} can be useful
20396 when combined with @code{locations} in the
20397 @code{<nginx-server-configuration>} records. The following example
20398 creates a server configuration with one location configuration, that
20399 will proxy requests to a upstream configuration, which will handle
20400 requests with two servers.
20405 (nginx-configuration
20407 (list (nginx-server-configuration
20408 (server-name '("www.example.com"))
20409 (root "/srv/http/www.example.com")
20412 (nginx-location-configuration
20414 (body '("proxy_pass http://server-proxy;"))))))))
20416 (list (nginx-upstream-configuration
20417 (name "server-proxy")
20418 (servers (list "server1.example.com"
20419 "server2.example.com")))))))
20422 @item @code{file} (default: @code{#f})
20423 If a configuration @var{file} is provided, this will be used, rather than
20424 generating a configuration file from the provided @code{log-directory},
20425 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
20426 proper operation, these arguments should match what is in @var{file} to ensure
20427 that the directories are created when the service is activated.
20429 This can be useful if you have an existing configuration file, or it's
20430 not possible to do what is required through the other parts of the
20431 nginx-configuration record.
20433 @item @code{server-names-hash-bucket-size} (default: @code{#f})
20434 Bucket size for the server names hash tables, defaults to @code{#f} to
20435 use the size of the processors cache line.
20437 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
20438 Maximum bucket size for the server names hash tables.
20440 @item @code{modules} (default: @code{'()})
20441 List of nginx dynamic modules to load. This should be a list of file
20442 names of loadable modules, as in this example:
20447 (file-append nginx-accept-language-module "\
20448 /etc/nginx/modules/ngx_http_accept_language_module.so")))
20451 @item @code{global-directives} (default: @code{'((events . ()))})
20452 Association list of global directives for the top level of the nginx
20453 configuration. Values may themselves be association lists.
20457 `((worker_processes . 16)
20459 (events . ((worker_connections . 1024)))))
20462 @item @code{extra-content} (default: @code{""})
20463 Extra content for the @code{http} block. Should be string or a string
20464 valued G-expression.
20469 @deftp {Data Type} nginx-server-configuration
20470 Data type representing the configuration of an nginx server block.
20471 This type has the following parameters:
20474 @item @code{listen} (default: @code{'("80" "443 ssl")})
20475 Each @code{listen} directive sets the address and port for IP, or the
20476 path for a UNIX-domain socket on which the server will accept requests.
20477 Both address and port, or only address or only port can be specified.
20478 An address may also be a hostname, for example:
20481 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
20484 @item @code{server-name} (default: @code{(list 'default)})
20485 A list of server names this server represents. @code{'default} represents the
20486 default server for connections matching no other server.
20488 @item @code{root} (default: @code{"/srv/http"})
20489 Root of the website nginx will serve.
20491 @item @code{locations} (default: @code{'()})
20492 A list of @dfn{nginx-location-configuration} or
20493 @dfn{nginx-named-location-configuration} records to use within this
20496 @item @code{index} (default: @code{(list "index.html")})
20497 Index files to look for when clients ask for a directory. If it cannot be found,
20498 Nginx will send the list of files in the directory.
20500 @item @code{try-files} (default: @code{'()})
20501 A list of files whose existence is checked in the specified order.
20502 @code{nginx} will use the first file it finds to process the request.
20504 @item @code{ssl-certificate} (default: @code{#f})
20505 Where to find the certificate for secure connections. Set it to @code{#f} if
20506 you don't have a certificate or you don't want to use HTTPS.
20508 @item @code{ssl-certificate-key} (default: @code{#f})
20509 Where to find the private key for secure connections. Set it to @code{#f} if
20510 you don't have a key or you don't want to use HTTPS.
20512 @item @code{server-tokens?} (default: @code{#f})
20513 Whether the server should add its configuration to response.
20515 @item @code{raw-content} (default: @code{'()})
20516 A list of raw lines added to the server block.
20521 @deftp {Data Type} nginx-upstream-configuration
20522 Data type representing the configuration of an nginx @code{upstream}
20523 block. This type has the following parameters:
20527 Name for this group of servers.
20529 @item @code{servers}
20530 Specify the addresses of the servers in the group. The address can be
20531 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
20532 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
20533 prefix @samp{unix:}. For addresses using an IP address or domain name,
20534 the default port is 80, and a different port can be specified
20540 @deftp {Data Type} nginx-location-configuration
20541 Data type representing the configuration of an nginx @code{location}
20542 block. This type has the following parameters:
20546 URI which this location block matches.
20548 @anchor{nginx-location-configuration body}
20550 Body of the location block, specified as a list of strings. This can contain
20552 configuration directives. For example, to pass requests to a upstream
20553 server group defined using an @code{nginx-upstream-configuration} block,
20554 the following directive would be specified in the body @samp{(list "proxy_pass
20555 http://upstream-name;")}.
20560 @deftp {Data Type} nginx-named-location-configuration
20561 Data type representing the configuration of an nginx named location
20562 block. Named location blocks are used for request redirection, and not
20563 used for regular request processing. This type has the following
20568 Name to identify this location block.
20571 @xref{nginx-location-configuration body}, as the body for named location
20572 blocks can be used in a similar way to the
20573 @code{nginx-location-configuration body}. One restriction is that the
20574 body of a named location block cannot contain location blocks.
20579 @subsubheading Varnish Cache
20581 Varnish is a fast cache server that sits in between web applications
20582 and end users. It proxies requests from clients and caches the
20583 accessed URLs such that multiple requests for the same resource only
20584 creates one request to the back-end.
20586 @defvr {Scheme Variable} varnish-service-type
20587 Service type for the Varnish daemon.
20590 @deftp {Data Type} varnish-configuration
20591 Data type representing the @code{varnish} service configuration.
20592 This type has the following parameters:
20595 @item @code{package} (default: @code{varnish})
20596 The Varnish package to use.
20598 @item @code{name} (default: @code{"default"})
20599 A name for this Varnish instance. Varnish will create a directory in
20600 @file{/var/varnish/} with this name and keep temporary files there. If
20601 the name starts with a forward slash, it is interpreted as an absolute
20604 Pass the @code{-n} argument to other Varnish programs to connect to the
20605 named instance, e.g.@: @command{varnishncsa -n default}.
20607 @item @code{backend} (default: @code{"localhost:8080"})
20608 The backend to use. This option has no effect if @code{vcl} is set.
20610 @item @code{vcl} (default: #f)
20611 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
20612 is @code{#f}, Varnish will proxy @code{backend} using the default
20613 configuration. Otherwise this must be a file-like object with valid
20616 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
20617 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
20618 can do something along these lines:
20621 (define %gnu-mirror
20622 (plain-file "gnu.vcl"
20624 backend gnu @{ .host = \"www.gnu.org\"; @}"))
20628 (services (cons (service varnish-service-type
20629 (varnish-configuration
20631 (vcl %gnu-mirror)))
20635 The configuration of an already running Varnish instance can be inspected
20636 and changed using the @command{varnishadm} program.
20638 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
20639 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
20640 comprehensive documentation on Varnish and its configuration language.
20642 @item @code{listen} (default: @code{'("localhost:80")})
20643 List of addresses Varnish will listen on.
20645 @item @code{storage} (default: @code{'("malloc,128m")})
20646 List of storage backends that will be available in VCL.
20648 @item @code{parameters} (default: @code{'()})
20649 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
20651 @item @code{extra-options} (default: @code{'()})
20652 Additional arguments to pass to the @command{varnishd} process.
20657 @subsubheading Patchwork
20659 Patchwork is a patch tracking system. It can collect patches sent to a
20660 mailing list, and display them in a web interface.
20662 @defvr {Scheme Variable} patchwork-service-type
20663 Service type for Patchwork.
20666 The following example is an example of a minimal service for Patchwork, for
20667 the @code{patchwork.example.com} domain.
20670 (service patchwork-service-type
20671 (patchwork-configuration
20672 (domain "patchwork.example.com")
20674 (patchwork-settings-module
20675 (allowed-hosts (list domain))
20676 (default-from-email "patchwork@@patchwork.example.com")))
20677 (getmail-retriever-config
20678 (getmail-retriever-configuration
20679 (type "SimpleIMAPSSLRetriever")
20680 (server "imap.example.com")
20682 (username "patchwork")
20684 (list (file-append coreutils "/bin/cat")
20685 "/etc/getmail-patchwork-imap-password"))
20687 '((mailboxes . ("Patches"))))))))
20691 There are three records for configuring the Patchwork service. The
20692 @code{<patchwork-configuration>} relates to the configuration for Patchwork
20693 within the HTTPD service.
20695 The @code{settings-module} field within the @code{<patchwork-configuration>}
20696 record can be populated with the @code{<patchwork-settings-module>} record,
20697 which describes a settings module that is generated within the Guix store.
20699 For the @code{database-configuration} field within the
20700 @code{<patchwork-settings-module>}, the
20701 @code{<patchwork-database-configuration>} must be used.
20703 @deftp {Data Type} patchwork-configuration
20704 Data type representing the Patchwork service configuration. This type has the
20705 following parameters:
20708 @item @code{patchwork} (default: @code{patchwork})
20709 The Patchwork package to use.
20711 @item @code{domain}
20712 The domain to use for Patchwork, this is used in the HTTPD service virtual
20715 @item @code{settings-module}
20716 The settings module to use for Patchwork. As a Django application, Patchwork
20717 is configured with a Python module containing the settings. This can either be
20718 an instance of the @code{<patchwork-settings-module>} record, any other record
20719 that represents the settings in the store, or a directory outside of the
20722 @item @code{static-path} (default: @code{"/static/"})
20723 The path under which the HTTPD service should serve the static files.
20725 @item @code{getmail-retriever-config}
20726 The getmail-retriever-configuration record value to use with
20727 Patchwork. Getmail will be configured with this value, the messages will be
20728 delivered to Patchwork.
20733 @deftp {Data Type} patchwork-settings-module
20734 Data type representing a settings module for Patchwork. Some of these
20735 settings relate directly to Patchwork, but others relate to Django, the web
20736 framework used by Patchwork, or the Django Rest Framework library. This type
20737 has the following parameters:
20740 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
20741 The database connection settings used for Patchwork. See the
20742 @code{<patchwork-database-configuration>} record type for more information.
20744 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
20745 Patchwork, as a Django web application uses a secret key for cryptographically
20746 signing values. This file should contain a unique unpredictable value.
20748 If this file does not exist, it will be created and populated with a random
20749 value by the patchwork-setup shepherd service.
20751 This setting relates to Django.
20753 @item @code{allowed-hosts}
20754 A list of valid hosts for this Patchwork service. This should at least include
20755 the domain specified in the @code{<patchwork-configuration>} record.
20757 This is a Django setting.
20759 @item @code{default-from-email}
20760 The email address from which Patchwork should send email by default.
20762 This is a Patchwork setting.
20764 @item @code{static-url} (default: @code{#f})
20765 The URL to use when serving static assets. It can be part of a URL, or a full
20766 URL, but must end in a @code{/}.
20768 If the default value is used, the @code{static-path} value from the
20769 @code{<patchwork-configuration>} record will be used.
20771 This is a Django setting.
20773 @item @code{admins} (default: @code{'()})
20774 Email addresses to send the details of errors that occur. Each value should
20775 be a list containing two elements, the name and then the email address.
20777 This is a Django setting.
20779 @item @code{debug?} (default: @code{#f})
20780 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
20781 messages will be shown.
20783 This is a Django setting.
20785 @item @code{enable-rest-api?} (default: @code{#t})
20786 Whether to enable the Patchwork REST API.
20788 This is a Patchwork setting.
20790 @item @code{enable-xmlrpc?} (default: @code{#t})
20791 Whether to enable the XML RPC API.
20793 This is a Patchwork setting.
20795 @item @code{force-https-links?} (default: @code{#t})
20796 Whether to use HTTPS links on Patchwork pages.
20798 This is a Patchwork setting.
20800 @item @code{extra-settings} (default: @code{""})
20801 Extra code to place at the end of the Patchwork settings module.
20806 @deftp {Data Type} patchwork-database-configuration
20807 Data type representing the database configuration for Patchwork.
20810 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
20811 The database engine to use.
20813 @item @code{name} (default: @code{"patchwork"})
20814 The name of the database to use.
20816 @item @code{user} (default: @code{"httpd"})
20817 The user to connect to the database as.
20819 @item @code{password} (default: @code{""})
20820 The password to use when connecting to the database.
20822 @item @code{host} (default: @code{""})
20823 The host to make the database connection to.
20825 @item @code{port} (default: @code{""})
20826 The port on which to connect to the database.
20831 @subsubheading Mumi
20833 @cindex Mumi, Debbugs Web interface
20834 @cindex Debbugs, Mumi Web interface
20835 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
20836 Web interface to the Debbugs bug tracker, by default for
20837 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
20838 but it also fetches and indexes mail retrieved from Debbugs.
20840 @defvr {Scheme Variable} mumi-service-type
20841 This is the service type for Mumi.
20844 @deftp {Data Type} mumi-configuration
20845 Data type representing the Mumi service configuration. This type has the
20849 @item @code{mumi} (default: @code{mumi})
20850 The Mumi package to use.
20852 @item @code{mailer?} (default: @code{#true})
20853 Whether to enable or disable the mailer component.
20855 @item @code{mumi-configuration-sender}
20856 The email address used as the sender for comments.
20858 @item @code{mumi-configuration-smtp}
20859 A URI to configure the SMTP settings for Mailutils. This could be
20860 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
20861 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
20862 mailutils, GNU@tie{}Mailutils}.
20868 @subsubheading FastCGI
20871 FastCGI is an interface between the front-end and the back-end of a web
20872 service. It is a somewhat legacy facility; new web services should
20873 generally just talk HTTP between the front-end and the back-end.
20874 However there are a number of back-end services such as PHP or the
20875 optimized HTTP Git repository access that use FastCGI, so we have
20876 support for it in Guix.
20878 To use FastCGI, you configure the front-end web server (e.g., nginx) to
20879 dispatch some subset of its requests to the fastcgi backend, which
20880 listens on a local TCP or UNIX socket. There is an intermediary
20881 @code{fcgiwrap} program that sits between the actual backend process and
20882 the web server. The front-end indicates which backend program to run,
20883 passing that information to the @code{fcgiwrap} process.
20885 @defvr {Scheme Variable} fcgiwrap-service-type
20886 A service type for the @code{fcgiwrap} FastCGI proxy.
20889 @deftp {Data Type} fcgiwrap-configuration
20890 Data type representing the configuration of the @code{fcgiwrap} service.
20891 This type has the following parameters:
20893 @item @code{package} (default: @code{fcgiwrap})
20894 The fcgiwrap package to use.
20896 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
20897 The socket on which the @code{fcgiwrap} process should listen, as a
20898 string. Valid @var{socket} values include
20899 @code{unix:@var{/path/to/unix/socket}},
20900 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
20901 @code{tcp6:[@var{ipv6_addr}]:port}.
20903 @item @code{user} (default: @code{fcgiwrap})
20904 @itemx @code{group} (default: @code{fcgiwrap})
20905 The user and group names, as strings, under which to run the
20906 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
20907 the user asks for the specific user or group names @code{fcgiwrap} that
20908 the corresponding user and/or group is present on the system.
20910 It is possible to configure a FastCGI-backed web service to pass HTTP
20911 authentication information from the front-end to the back-end, and to
20912 allow @code{fcgiwrap} to run the back-end process as a corresponding
20913 local user. To enable this capability on the back-end, run
20914 @code{fcgiwrap} as the @code{root} user and group. Note that this
20915 capability also has to be configured on the front-end as well.
20920 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
20921 with some additional features useful for sites of any size.
20923 These features include:
20925 @item Adaptive process spawning
20926 @item Basic statistics (similar to Apache's mod_status)
20927 @item Advanced process management with graceful stop/start
20928 @item Ability to start workers with different uid/gid/chroot/environment
20929 and different php.ini (replaces safe_mode)
20930 @item Stdout & stderr logging
20931 @item Emergency restart in case of accidental opcode cache destruction
20932 @item Accelerated upload support
20933 @item Support for a "slowlog"
20934 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
20935 a special function to finish request & flush all data while continuing to do
20936 something time-consuming (video converting, stats processing, etc.)
20938 ...@: and much more.
20940 @defvr {Scheme Variable} php-fpm-service-type
20941 A Service type for @code{php-fpm}.
20944 @deftp {Data Type} php-fpm-configuration
20945 Data Type for php-fpm service configuration.
20947 @item @code{php} (default: @code{php})
20948 The php package to use.
20949 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
20950 The address on which to accept FastCGI requests. Valid syntaxes are:
20952 @item @code{"ip.add.re.ss:port"}
20953 Listen on a TCP socket to a specific address on a specific port.
20954 @item @code{"port"}
20955 Listen on a TCP socket to all addresses on a specific port.
20956 @item @code{"/path/to/unix/socket"}
20957 Listen on a unix socket.
20960 @item @code{user} (default: @code{php-fpm})
20961 User who will own the php worker processes.
20962 @item @code{group} (default: @code{php-fpm})
20963 Group of the worker processes.
20964 @item @code{socket-user} (default: @code{php-fpm})
20965 User who can speak to the php-fpm socket.
20966 @item @code{socket-group} (default: @code{nginx})
20967 Group that can speak to the php-fpm socket.
20968 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
20969 The process id of the php-fpm process is written to this file
20970 once the service has started.
20971 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
20972 Log for the php-fpm master process.
20973 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
20974 Detailed settings for the php-fpm process manager.
20977 @item @code{<php-fpm-dynamic-process-manager-configuration>}
20978 @item @code{<php-fpm-static-process-manager-configuration>}
20979 @item @code{<php-fpm-on-demand-process-manager-configuration>}
20981 @item @code{display-errors} (default @code{#f})
20982 Determines whether php errors and warning should be sent to clients
20983 and displayed in their browsers.
20984 This is useful for local php development, but a security risk for public sites,
20985 as error messages can reveal passwords and personal data.
20986 @item @code{timezone} (default @code{#f})
20987 Specifies @code{php_admin_value[date.timezone]} parameter.
20988 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
20989 This file will log the @code{stderr} outputs of php worker processes.
20990 Can be set to @code{#f} to disable logging.
20991 @item @code{file} (default @code{#f})
20992 An optional override of the whole configuration.
20993 You can use the @code{mixed-text-file} function or an absolute filepath for it.
20997 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
20998 Data Type for the @code{dynamic} php-fpm process manager. With the
20999 @code{dynamic} process manager, spare worker processes are kept around
21000 based on it's configured limits.
21002 @item @code{max-children} (default: @code{5})
21003 Maximum of worker processes.
21004 @item @code{start-servers} (default: @code{2})
21005 How many worker processes should be started on start-up.
21006 @item @code{min-spare-servers} (default: @code{1})
21007 How many spare worker processes should be kept around at minimum.
21008 @item @code{max-spare-servers} (default: @code{3})
21009 How many spare worker processes should be kept around at maximum.
21013 @deftp {Data type} php-fpm-static-process-manager-configuration
21014 Data Type for the @code{static} php-fpm process manager. With the
21015 @code{static} process manager, an unchanging number of worker processes
21018 @item @code{max-children} (default: @code{5})
21019 Maximum of worker processes.
21023 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
21024 Data Type for the @code{on-demand} php-fpm process manager. With the
21025 @code{on-demand} process manager, worker processes are only created as
21028 @item @code{max-children} (default: @code{5})
21029 Maximum of worker processes.
21030 @item @code{process-idle-timeout} (default: @code{10})
21031 The time in seconds after which a process with no requests is killed.
21036 @deffn {Scheme Procedure} nginx-php-location @
21037 [#:nginx-package nginx] @
21038 [socket (string-append "/var/run/php" @
21039 (version-major (package-version php)) @
21041 A helper function to quickly add php to an @code{nginx-server-configuration}.
21044 A simple services setup for nginx with php can look like this:
21046 (services (cons* (service dhcp-client-service-type)
21047 (service php-fpm-service-type)
21048 (service nginx-service-type
21049 (nginx-server-configuration
21050 (server-name '("example.com"))
21051 (root "/srv/http/")
21053 (list (nginx-php-location)))
21055 (ssl-certificate #f)
21056 (ssl-certificate-key #f)))
21060 @cindex cat-avatar-generator
21061 The cat avatar generator is a simple service to demonstrate the use of php-fpm
21062 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
21063 the hash of a user's email address.
21065 @deffn {Scheme Procedure} cat-avatar-generator-service @
21066 [#:cache-dir "/var/cache/cat-avatar-generator"] @
21067 [#:package cat-avatar-generator] @
21068 [#:configuration (nginx-server-configuration)]
21069 Returns an nginx-server-configuration that inherits @code{configuration}. It
21070 extends the nginx configuration to add a server block that serves @code{package},
21071 a version of cat-avatar-generator. During execution, cat-avatar-generator will
21072 be able to use @code{cache-dir} as its cache directory.
21075 A simple setup for cat-avatar-generator can look like this:
21077 (services (cons* (cat-avatar-generator-service
21079 (nginx-server-configuration
21080 (server-name '("example.com"))))
21085 @subsubheading Hpcguix-web
21087 @cindex hpcguix-web
21088 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
21089 program is a customizable web interface to browse Guix packages,
21090 initially designed for users of high-performance computing (HPC)
21093 @defvr {Scheme Variable} hpcguix-web-service-type
21094 The service type for @code{hpcguix-web}.
21097 @deftp {Data Type} hpcguix-web-configuration
21098 Data type for the hpcguix-web service configuration.
21102 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
21103 configuration. The main items available in this spec are:
21106 @item @code{title-prefix} (default: @code{"hpcguix | "})
21107 The page title prefix.
21109 @item @code{guix-command} (default: @code{"guix"})
21110 The @command{guix} command.
21112 @item @code{package-filter-proc} (default: @code{(const #t)})
21113 A procedure specifying how to filter packages that are displayed.
21115 @item @code{package-page-extension-proc} (default: @code{(const '())})
21116 Extension package for @code{hpcguix-web}.
21118 @item @code{menu} (default: @code{'()})
21119 Additional entry in page @code{menu}.
21121 @item @code{channels} (default: @code{%default-channels})
21122 List of channels from which the package list is built (@pxref{Channels}).
21124 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
21125 The expiration time, in seconds, after which the package list is rebuilt from
21126 the latest instances of the given channels.
21129 See the hpcguix-web repository for a
21130 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
21133 @item @code{package} (default: @code{hpcguix-web})
21134 The hpcguix-web package to use.
21138 A typical hpcguix-web service declaration looks like this:
21141 (service hpcguix-web-service-type
21142 (hpcguix-web-configuration
21144 #~(define site-config
21145 (hpcweb-configuration
21146 (title-prefix "Guix-HPC - ")
21147 (menu '(("/about" "ABOUT"))))))))
21151 The hpcguix-web service periodically updates the package list it publishes by
21152 pulling channels from Git. To that end, it needs to access X.509 certificates
21153 so that it can authenticate Git servers when communicating over HTTPS, and it
21154 assumes that @file{/etc/ssl/certs} contains those certificates.
21156 Thus, make sure to add @code{nss-certs} or another certificate package to the
21157 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
21158 more information on X.509 certificates.
21161 @node Certificate Services
21162 @subsection Certificate Services
21165 @cindex HTTP, HTTPS
21166 @cindex Let's Encrypt
21167 @cindex TLS certificates
21168 The @code{(gnu services certbot)} module provides a service to
21169 automatically obtain a valid TLS certificate from the Let's Encrypt
21170 certificate authority. These certificates can then be used to serve
21171 content securely over HTTPS or other TLS-based protocols, with the
21172 knowledge that the client will be able to verify the server's
21175 @url{https://letsencrypt.org/, Let's Encrypt} provides the
21176 @code{certbot} tool to automate the certification process. This tool
21177 first securely generates a key on the server. It then makes a request
21178 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
21179 checks that the request originates from the host in question by using a
21180 challenge-response protocol, requiring the server to provide its
21181 response over HTTP. If that protocol completes successfully, the CA
21182 signs the key, resulting in a certificate. That certificate is valid
21183 for a limited period of time, and therefore to continue to provide TLS
21184 services, the server needs to periodically ask the CA to renew its
21187 The certbot service automates this process: the initial key
21188 generation, the initial certification request to the Let's Encrypt
21189 service, the web server challenge/response integration, writing the
21190 certificate to disk, the automated periodic renewals, and the deployment
21191 tasks associated with the renewal (e.g.@: reloading services, copying keys
21192 with different permissions).
21194 Certbot is run twice a day, at a random minute within the hour. It
21195 won't do anything until your certificates are due for renewal or
21196 revoked, but running it regularly would give your service a chance of
21197 staying online in case a Let's Encrypt-initiated revocation happened for
21200 By using this service, you agree to the ACME Subscriber Agreement, which
21201 can be found there:
21202 @url{https://acme-v01.api.letsencrypt.org/directory}.
21204 @defvr {Scheme Variable} certbot-service-type
21205 A service type for the @code{certbot} Let's Encrypt client. Its value
21206 must be a @code{certbot-configuration} record as in this example:
21209 (define %nginx-deploy-hook
21211 "nginx-deploy-hook"
21212 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
21213 (kill pid SIGHUP))))
21215 (service certbot-service-type
21216 (certbot-configuration
21217 (email "foo@@example.net")
21220 (certificate-configuration
21221 (domains '("example.net" "www.example.net"))
21222 (deploy-hook %nginx-deploy-hook))
21223 (certificate-configuration
21224 (domains '("bar.example.net")))))))
21227 See below for details about @code{certbot-configuration}.
21230 @deftp {Data Type} certbot-configuration
21231 Data type representing the configuration of the @code{certbot} service.
21232 This type has the following parameters:
21235 @item @code{package} (default: @code{certbot})
21236 The certbot package to use.
21238 @item @code{webroot} (default: @code{/var/www})
21239 The directory from which to serve the Let's Encrypt challenge/response
21242 @item @code{certificates} (default: @code{()})
21243 A list of @code{certificates-configuration}s for which to generate
21244 certificates and request signatures. Each certificate has a @code{name}
21245 and several @code{domains}.
21248 Mandatory email used for registration, recovery contact, and important
21249 account notifications.
21251 @item @code{server} (default: @code{#f})
21252 Optional URL of ACME server. Setting this overrides certbot's default,
21253 which is the Let's Encrypt server.
21255 @item @code{rsa-key-size} (default: @code{2048})
21256 Size of the RSA key.
21258 @item @code{default-location} (default: @i{see below})
21259 The default @code{nginx-location-configuration}. Because @code{certbot}
21260 needs to be able to serve challenges and responses, it needs to be able
21261 to run a web server. It does so by extending the @code{nginx} web
21262 service with an @code{nginx-server-configuration} listening on the
21263 @var{domains} on port 80, and which has a
21264 @code{nginx-location-configuration} for the @code{/.well-known/} URI
21265 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
21266 these nginx configuration data types.
21268 Requests to other URL paths will be matched by the
21269 @code{default-location}, which if present is added to all
21270 @code{nginx-server-configuration}s.
21272 By default, the @code{default-location} will issue a redirect from
21273 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
21274 you to define what to serve on your site via @code{https}.
21276 Pass @code{#f} to not issue a default location.
21280 @deftp {Data Type} certificate-configuration
21281 Data type representing the configuration of a certificate.
21282 This type has the following parameters:
21285 @item @code{name} (default: @i{see below})
21286 This name is used by Certbot for housekeeping and in file paths; it
21287 doesn't affect the content of the certificate itself. To see
21288 certificate names, run @code{certbot certificates}.
21290 Its default is the first provided domain.
21292 @item @code{domains} (default: @code{()})
21293 The first domain provided will be the subject CN of the certificate, and
21294 all domains will be Subject Alternative Names on the certificate.
21296 @item @code{challenge} (default: @code{#f})
21297 The challenge type that has to be run by certbot. If @code{#f} is specified,
21298 default to the HTTP challenge. If a value is specified, defaults to the
21299 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
21300 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
21301 and gives Let's Encrypt permission to log the public IP address of the
21302 requesting machine.
21304 @item @code{authentication-hook} (default: @code{#f})
21305 Command to be run in a shell once for each certificate challenge to be
21306 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
21307 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
21308 contains the validation string and @code{$CERTBOT_TOKEN} contains the
21309 file name of the resource requested when performing an HTTP-01 challenge.
21311 @item @code{cleanup-hook} (default: @code{#f})
21312 Command to be run in a shell once for each certificate challenge that
21313 have been answered by the @code{auth-hook}. For this command, the shell
21314 variables available in the @code{auth-hook} script are still available, and
21315 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
21316 of the @code{auth-hook} script.
21318 @item @code{deploy-hook} (default: @code{#f})
21319 Command to be run in a shell once for each successfully issued
21320 certificate. For this command, the shell variable
21321 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
21322 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
21323 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
21324 contain a space-delimited list of renewed certificate domains (for
21325 example, @samp{"example.com www.example.com"}.
21330 For each @code{certificate-configuration}, the certificate is saved to
21331 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
21332 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
21334 @subsection DNS Services
21335 @cindex DNS (domain name system)
21336 @cindex domain name system (DNS)
21338 The @code{(gnu services dns)} module provides services related to the
21339 @dfn{domain name system} (DNS). It provides a server service for hosting
21340 an @emph{authoritative} DNS server for multiple zones, slave or master.
21341 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
21342 caching and forwarding DNS server for the LAN, which uses
21343 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
21345 @subsubheading Knot Service
21347 An example configuration of an authoritative server for two zones, one master
21351 (define-zone-entries example.org.zone
21352 ;; Name TTL Class Type Data
21353 ("@@" "" "IN" "A" "127.0.0.1")
21354 ("@@" "" "IN" "NS" "ns")
21355 ("ns" "" "IN" "A" "127.0.0.1"))
21357 (define master-zone
21358 (knot-zone-configuration
21359 (domain "example.org")
21361 (origin "example.org")
21362 (entries example.org.zone)))))
21365 (knot-zone-configuration
21366 (domain "plop.org")
21367 (dnssec-policy "default")
21368 (master (list "plop-master"))))
21370 (define plop-master
21371 (knot-remote-configuration
21373 (address (list "208.76.58.171"))))
21377 (services (cons* (service knot-service-type
21378 (knot-configuration
21379 (remotes (list plop-master))
21380 (zones (list master-zone slave-zone))))
21385 @deffn {Scheme Variable} knot-service-type
21386 This is the type for the Knot DNS server.
21388 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
21389 zones, that is to say domain names you would buy from a registrar. This server
21390 is not a resolver, meaning that it can only resolve names for which it is
21391 authoritative. This server can be configured to serve zones as a master server
21392 or a slave server as a per-zone basis. Slave zones will get their data from
21393 masters, and will serve it as an authoritative server. From the point of view
21394 of a resolver, there is no difference between master and slave.
21396 The following data types are used to configure the Knot DNS server:
21399 @deftp {Data Type} knot-key-configuration
21400 Data type representing a key.
21401 This type has the following parameters:
21404 @item @code{id} (default: @code{""})
21405 An identifier for other configuration fields to refer to this key. IDs must
21406 be unique and must not be empty.
21408 @item @code{algorithm} (default: @code{#f})
21409 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
21410 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
21411 and @code{'hmac-sha512}.
21413 @item @code{secret} (default: @code{""})
21414 The secret key itself.
21419 @deftp {Data Type} knot-acl-configuration
21420 Data type representing an Access Control List (ACL) configuration.
21421 This type has the following parameters:
21424 @item @code{id} (default: @code{""})
21425 An identifier for ether configuration fields to refer to this key. IDs must be
21426 unique and must not be empty.
21428 @item @code{address} (default: @code{'()})
21429 An ordered list of IP addresses, network subnets, or network ranges represented
21430 with strings. The query must match one of them. Empty value means that
21431 address match is not required.
21433 @item @code{key} (default: @code{'()})
21434 An ordered list of references to keys represented with strings. The string
21435 must match a key ID defined in a @code{knot-key-configuration}. No key means
21436 that a key is not require to match that ACL.
21438 @item @code{action} (default: @code{'()})
21439 An ordered list of actions that are permitted or forbidden by this ACL. Possible
21440 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
21441 and @code{'update}.
21443 @item @code{deny?} (default: @code{#f})
21444 When true, the ACL defines restrictions. Listed actions are forbidden. When
21445 false, listed actions are allowed.
21450 @deftp {Data Type} zone-entry
21451 Data type representing a record entry in a zone file.
21452 This type has the following parameters:
21455 @item @code{name} (default: @code{"@@"})
21456 The name of the record. @code{"@@"} refers to the origin of the zone. Names
21457 are relative to the origin of the zone. For example, in the @code{example.org}
21458 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
21459 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
21460 refers to @code{ns.example.org}.
21462 @item @code{ttl} (default: @code{""})
21463 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
21465 @item @code{class} (default: @code{"IN"})
21466 The class of the record. Knot currently supports only @code{"IN"} and
21467 partially @code{"CH"}.
21469 @item @code{type} (default: @code{"A"})
21470 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
21471 address), NS (Name Server) and MX (Mail eXchange). Many other types are
21474 @item @code{data} (default: @code{""})
21475 The data contained in the record. For instance an IP address associated with
21476 an A record, or a domain name associated with an NS record. Remember that
21477 domain names are relative to the origin unless they end with a dot.
21482 @deftp {Data Type} zone-file
21483 Data type representing the content of a zone file.
21484 This type has the following parameters:
21487 @item @code{entries} (default: @code{'()})
21488 The list of entries. The SOA record is taken care of, so you don't need to
21489 put it in the list of entries. This list should probably contain an entry
21490 for your primary authoritative DNS server. Other than using a list of entries
21491 directly, you can use @code{define-zone-entries} to define a object containing
21492 the list of entries more easily, that you can later pass to the @code{entries}
21493 field of the @code{zone-file}.
21495 @item @code{origin} (default: @code{""})
21496 The name of your zone. This parameter cannot be empty.
21498 @item @code{ns} (default: @code{"ns"})
21499 The domain of your primary authoritative DNS server. The name is relative to
21500 the origin, unless it ends with a dot. It is mandatory that this primary
21501 DNS server corresponds to an NS record in the zone and that it is associated
21502 to an IP address in the list of entries.
21504 @item @code{mail} (default: @code{"hostmaster"})
21505 An email address people can contact you at, as the owner of the zone. This
21506 is translated as @code{<mail>@@<origin>}.
21508 @item @code{serial} (default: @code{1})
21509 The serial number of the zone. As this is used to keep track of changes by
21510 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
21511 Always increment it when you make a change in your zone.
21513 @item @code{refresh} (default: @code{(* 2 24 3600)})
21514 The frequency at which slaves will do a zone transfer. This value is a number
21515 of seconds. It can be computed by multiplications or with
21516 @code{(string->duration)}.
21518 @item @code{retry} (default: @code{(* 15 60)})
21519 The period after which a slave will retry to contact its master when it fails
21520 to do so a first time.
21522 @item @code{expiry} (default: @code{(* 14 24 3600)})
21523 Default TTL of records. Existing records are considered correct for at most
21524 this amount of time. After this period, resolvers will invalidate their cache
21525 and check again that it still exists.
21527 @item @code{nx} (default: @code{3600})
21528 Default TTL of inexistant records. This delay is usually short because you want
21529 your new domains to reach everyone quickly.
21534 @deftp {Data Type} knot-remote-configuration
21535 Data type representing a remote configuration.
21536 This type has the following parameters:
21539 @item @code{id} (default: @code{""})
21540 An identifier for other configuration fields to refer to this remote. IDs must
21541 be unique and must not be empty.
21543 @item @code{address} (default: @code{'()})
21544 An ordered list of destination IP addresses. Addresses are tried in sequence.
21545 An optional port can be given with the @@ separator. For instance:
21546 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
21548 @item @code{via} (default: @code{'()})
21549 An ordered list of source IP addresses. An empty list will have Knot choose
21550 an appropriate source IP. An optional port can be given with the @@ separator.
21551 The default is to choose at random.
21553 @item @code{key} (default: @code{#f})
21554 A reference to a key, that is a string containing the identifier of a key
21555 defined in a @code{knot-key-configuration} field.
21560 @deftp {Data Type} knot-keystore-configuration
21561 Data type representing a keystore to hold dnssec keys.
21562 This type has the following parameters:
21565 @item @code{id} (default: @code{""})
21566 The id of the keystore. It must not be empty.
21568 @item @code{backend} (default: @code{'pem})
21569 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
21571 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
21572 The configuration string of the backend. An example for the PKCS#11 is:
21573 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
21574 For the pem backend, the string represents a path in the file system.
21579 @deftp {Data Type} knot-policy-configuration
21580 Data type representing a dnssec policy. Knot DNS is able to automatically
21581 sign your zones. It can either generate and manage your keys automatically or
21582 use keys that you generate.
21584 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
21585 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
21586 zone. In order to be trusted, the KSK needs to be present in the parent zone
21587 (usually a top-level domain). If your registrar supports dnssec, you will
21588 have to send them your KSK's hash so they can add a DS record in their zone.
21589 This is not automated and need to be done each time you change your KSK.
21591 The policy also defines the lifetime of keys. Usually, ZSK can be changed
21592 easily and use weaker cryptographic functions (they use lower parameters) in
21593 order to sign records quickly, so they are changed often. The KSK however
21594 requires manual interaction with the registrar, so they are changed less often
21595 and use stronger parameters because they sign only one record.
21597 This type has the following parameters:
21600 @item @code{id} (default: @code{""})
21601 The id of the policy. It must not be empty.
21603 @item @code{keystore} (default: @code{"default"})
21604 A reference to a keystore, that is a string containing the identifier of a
21605 keystore defined in a @code{knot-keystore-configuration} field. The
21606 @code{"default"} identifier means the default keystore (a kasp database that
21607 was setup by this service).
21609 @item @code{manual?} (default: @code{#f})
21610 Whether the key management is manual or automatic.
21612 @item @code{single-type-signing?} (default: @code{#f})
21613 When @code{#t}, use the Single-Type Signing Scheme.
21615 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
21616 An algorithm of signing keys and issued signatures.
21618 @item @code{ksk-size} (default: @code{256})
21619 The length of the KSK. Note that this value is correct for the default
21620 algorithm, but would be unsecure for other algorithms.
21622 @item @code{zsk-size} (default: @code{256})
21623 The length of the ZSK. Note that this value is correct for the default
21624 algorithm, but would be unsecure for other algorithms.
21626 @item @code{dnskey-ttl} (default: @code{'default})
21627 The TTL value for DNSKEY records added into zone apex. The special
21628 @code{'default} value means same as the zone SOA TTL.
21630 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
21631 The period between ZSK publication and the next rollover initiation.
21633 @item @code{propagation-delay} (default: @code{(* 24 3600)})
21634 An extra delay added for each key rollover step. This value should be high
21635 enough to cover propagation of data from the master server to all slaves.
21637 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
21638 A validity period of newly issued signatures.
21640 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
21641 A period how long before a signature expiration the signature will be refreshed.
21643 @item @code{nsec3?} (default: @code{#f})
21644 When @code{#t}, NSEC3 will be used instead of NSEC.
21646 @item @code{nsec3-iterations} (default: @code{5})
21647 The number of additional times the hashing is performed.
21649 @item @code{nsec3-salt-length} (default: @code{8})
21650 The length of a salt field in octets, which is appended to the original owner
21651 name before hashing.
21653 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
21654 The validity period of newly issued salt field.
21659 @deftp {Data Type} knot-zone-configuration
21660 Data type representing a zone served by Knot.
21661 This type has the following parameters:
21664 @item @code{domain} (default: @code{""})
21665 The domain served by this configuration. It must not be empty.
21667 @item @code{file} (default: @code{""})
21668 The file where this zone is saved. This parameter is ignored by master zones.
21669 Empty means default location that depends on the domain name.
21671 @item @code{zone} (default: @code{(zone-file)})
21672 The content of the zone file. This parameter is ignored by slave zones. It
21673 must contain a zone-file record.
21675 @item @code{master} (default: @code{'()})
21676 A list of master remotes. When empty, this zone is a master. When set, this
21677 zone is a slave. This is a list of remotes identifiers.
21679 @item @code{ddns-master} (default: @code{#f})
21680 The main master. When empty, it defaults to the first master in the list of
21683 @item @code{notify} (default: @code{'()})
21684 A list of slave remote identifiers.
21686 @item @code{acl} (default: @code{'()})
21687 A list of acl identifiers.
21689 @item @code{semantic-checks?} (default: @code{#f})
21690 When set, this adds more semantic checks to the zone.
21692 @item @code{disable-any?} (default: @code{#f})
21693 When set, this forbids queries of the ANY type.
21695 @item @code{zonefile-sync} (default: @code{0})
21696 The delay between a modification in memory and on disk. 0 means immediate
21699 @item @code{zonefile-load} (default: @code{#f})
21700 The way the zone file contents are applied during zone load. Possible values
21704 @item @code{#f} for using the default value from Knot,
21705 @item @code{'none} for not using the zone file at all,
21706 @item @code{'difference} for computing the difference between already available
21707 contents and zone contents and applying it to the current zone contents,
21708 @item @code{'difference-no-serial} for the same as @code{'difference}, but
21709 ignoring the SOA serial in the zone file, while the server takes care of it
21711 @item @code{'whole} for loading zone contents from the zone file.
21714 @item @code{journal-content} (default: @code{#f})
21715 The way the journal is used to store zone and its changes. Possible values
21716 are @code{'none} to not use it at all, @code{'changes} to store changes and
21717 @code{'all} to store contents. @code{#f} does not set this option, so the
21718 default value from Knot is used.
21720 @item @code{max-journal-usage} (default: @code{#f})
21721 The maximum size for the journal on disk. @code{#f} does not set this option,
21722 so the default value from Knot is used.
21724 @item @code{max-journal-depth} (default: @code{#f})
21725 The maximum size of the history. @code{#f} does not set this option, so the
21726 default value from Knot is used.
21728 @item @code{max-zone-size} (default: @code{#f})
21729 The maximum size of the zone file. This limit is enforced for incoming
21730 transfer and updates. @code{#f} does not set this option, so the default
21731 value from Knot is used.
21733 @item @code{dnssec-policy} (default: @code{#f})
21734 A reference to a @code{knot-policy-configuration} record, or the special
21735 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
21738 @item @code{serial-policy} (default: @code{'increment})
21739 A policy between @code{'increment} and @code{'unixtime}.
21744 @deftp {Data Type} knot-configuration
21745 Data type representing the Knot configuration.
21746 This type has the following parameters:
21749 @item @code{knot} (default: @code{knot})
21752 @item @code{run-directory} (default: @code{"/var/run/knot"})
21753 The run directory. This directory will be used for pid file and sockets.
21755 @item @code{includes} (default: @code{'()})
21756 A list of strings or file-like objects denoting other files that must be
21757 included at the top of the configuration file.
21759 @cindex secrets, Knot service
21760 This can be used to manage secrets out-of-band. For example, secret
21761 keys may be stored in an out-of-band file not managed by Guix, and
21762 thus not visible in @file{/gnu/store}---e.g., you could store secret
21763 key configuration in @file{/etc/knot/secrets.conf} and add this file
21764 to the @code{includes} list.
21766 One can generate a secret tsig key (for nsupdate and zone transfers with the
21767 keymgr command from the knot package. Note that the package is not automatically
21768 installed by the service. The following example shows how to generate a new
21772 keymgr -t mysecret > /etc/knot/secrets.conf
21773 chmod 600 /etc/knot/secrets.conf
21776 Also note that the generated key will be named @var{mysecret}, so it is the
21777 name that needs to be used in the @var{key} field of the
21778 @code{knot-acl-configuration} record and in other places that need to refer
21781 It can also be used to add configuration not supported by this interface.
21783 @item @code{listen-v4} (default: @code{"0.0.0.0"})
21784 An ip address on which to listen.
21786 @item @code{listen-v6} (default: @code{"::"})
21787 An ip address on which to listen.
21789 @item @code{listen-port} (default: @code{53})
21790 A port on which to listen.
21792 @item @code{keys} (default: @code{'()})
21793 The list of knot-key-configuration used by this configuration.
21795 @item @code{acls} (default: @code{'()})
21796 The list of knot-acl-configuration used by this configuration.
21798 @item @code{remotes} (default: @code{'()})
21799 The list of knot-remote-configuration used by this configuration.
21801 @item @code{zones} (default: @code{'()})
21802 The list of knot-zone-configuration used by this configuration.
21807 @subsubheading Knot Resolver Service
21809 @deffn {Scheme Variable} knot-resolver-service-type
21810 This this the type of the knot resolver service, whose value should be
21811 an @code{knot-resolver-configuration} object as in this example:
21814 (service knot-resolver-service-type
21815 (knot-resolver-configuration
21816 (kresd-config-file (plain-file "kresd.conf" "
21817 net.listen('192.168.0.1', 5353)
21818 user('knot-resolver', 'knot-resolver')
21819 modules = @{ 'hints > iterate', 'stats', 'predict' @}
21820 cache.size = 100 * MB
21824 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
21827 @deftp {Data Type} knot-resolver-configuration
21828 Data type representing the configuration of knot-resolver.
21831 @item @code{package} (default: @var{knot-resolver})
21832 Package object of the knot DNS resolver.
21834 @item @code{kresd-config-file} (default: %kresd.conf)
21835 File-like object of the kresd configuration file to use, by default it
21836 will listen on @code{127.0.0.1} and @code{::1}.
21838 @item @code{garbage-collection-interval} (default: 1000)
21839 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
21845 @subsubheading Dnsmasq Service
21847 @deffn {Scheme Variable} dnsmasq-service-type
21848 This is the type of the dnsmasq service, whose value should be an
21849 @code{dnsmasq-configuration} object as in this example:
21852 (service dnsmasq-service-type
21853 (dnsmasq-configuration
21855 (servers '("192.168.1.1"))))
21859 @deftp {Data Type} dnsmasq-configuration
21860 Data type representing the configuration of dnsmasq.
21863 @item @code{package} (default: @var{dnsmasq})
21864 Package object of the dnsmasq server.
21866 @item @code{no-hosts?} (default: @code{#f})
21867 When true, don't read the hostnames in /etc/hosts.
21869 @item @code{port} (default: @code{53})
21870 The port to listen on. Setting this to zero completely disables DNS
21871 responses, leaving only DHCP and/or TFTP functions.
21873 @item @code{local-service?} (default: @code{#t})
21874 Accept DNS queries only from hosts whose address is on a local subnet,
21875 ie a subnet for which an interface exists on the server.
21877 @item @code{listen-addresses} (default: @code{'()})
21878 Listen on the given IP addresses.
21880 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
21881 The file to read the IP address of the upstream nameservers from.
21883 @item @code{no-resolv?} (default: @code{#f})
21884 When true, don't read @var{resolv-file}.
21886 @item @code{servers} (default: @code{'()})
21887 Specify IP address of upstream servers directly.
21889 @item @code{addresses} (default: @code{'()})
21890 For each entry, specify an IP address to return for any host in the
21891 given domains. Queries in the domains are never forwarded and always
21892 replied to with the specified IP address.
21894 This is useful for redirecting hosts locally, for example:
21897 (service dnsmasq-service-type
21898 (dnsmasq-configuration
21900 '(; Redirect to a local web-server.
21901 "/example.org/127.0.0.1"
21902 ; Redirect subdomain to a specific IP.
21903 "/subdomain.example.org/192.168.1.42"))))
21906 Note that rules in @file{/etc/hosts} take precedence over this.
21908 @item @code{cache-size} (default: @code{150})
21909 Set the size of dnsmasq's cache. Setting the cache size to zero
21912 @item @code{negative-cache?} (default: @code{#t})
21913 When false, disable negative caching.
21918 @subsubheading ddclient Service
21921 The ddclient service described below runs the ddclient daemon, which takes
21922 care of automatically updating DNS entries for service providers such as
21923 @uref{https://dyn.com/dns/, Dyn}.
21925 The following example show instantiates the service with its default
21929 (service ddclient-service-type)
21932 Note that ddclient needs to access credentials that are stored in a
21933 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
21934 @code{secret-file} below.) You are expected to create this file manually, in
21935 an ``out-of-band'' fashion (you @emph{could} make this file part of the
21936 service configuration, for instance by using @code{plain-file}, but it will be
21937 world-readable @i{via} @file{/gnu/store}.) See the examples in the
21938 @file{share/ddclient} directory of the @code{ddclient} package.
21940 @c %start of fragment
21942 Available @code{ddclient-configuration} fields are:
21944 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
21945 The ddclient package.
21949 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
21950 The period after which ddclient will retry to check IP and domain name.
21952 Defaults to @samp{300}.
21956 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
21957 Use syslog for the output.
21959 Defaults to @samp{#t}.
21963 @deftypevr {@code{ddclient-configuration} parameter} string mail
21966 Defaults to @samp{"root"}.
21970 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
21971 Mail failed update to user.
21973 Defaults to @samp{"root"}.
21977 @deftypevr {@code{ddclient-configuration} parameter} string pid
21978 The ddclient PID file.
21980 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
21984 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
21985 Enable SSL support.
21987 Defaults to @samp{#t}.
21991 @deftypevr {@code{ddclient-configuration} parameter} string user
21992 Specifies the user name or ID that is used when running ddclient
21995 Defaults to @samp{"ddclient"}.
21999 @deftypevr {@code{ddclient-configuration} parameter} string group
22000 Group of the user who will run the ddclient program.
22002 Defaults to @samp{"ddclient"}.
22006 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
22007 Secret file which will be appended to @file{ddclient.conf} file. This
22008 file contains credentials for use by ddclient. You are expected to
22009 create it manually.
22011 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
22015 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
22016 Extra options will be appended to @file{ddclient.conf} file.
22018 Defaults to @samp{()}.
22023 @c %end of fragment
22027 @subsection VPN Services
22028 @cindex VPN (virtual private network)
22029 @cindex virtual private network (VPN)
22031 The @code{(gnu services vpn)} module provides services related to
22032 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
22033 your machine to connect to a VPN, and a @emph{server} service for your machine
22034 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
22036 @deffn {Scheme Procedure} openvpn-client-service @
22037 [#:config (openvpn-client-configuration)]
22039 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
22042 @deffn {Scheme Procedure} openvpn-server-service @
22043 [#:config (openvpn-server-configuration)]
22045 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
22047 Both can be run simultaneously.
22050 @c %automatically generated documentation
22052 Available @code{openvpn-client-configuration} fields are:
22054 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
22055 The OpenVPN package.
22059 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
22060 The OpenVPN pid file.
22062 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22066 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
22067 The protocol (UDP or TCP) used to open a channel between clients and
22070 Defaults to @samp{udp}.
22074 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
22075 The device type used to represent the VPN connection.
22077 Defaults to @samp{tun}.
22081 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
22082 The certificate authority to check connections against.
22084 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22088 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
22089 The certificate of the machine the daemon is running on. It should be
22090 signed by the authority given in @code{ca}.
22092 Defaults to @samp{"/etc/openvpn/client.crt"}.
22096 @deftypevr {@code{openvpn-client-configuration} parameter} string key
22097 The key of the machine the daemon is running on. It must be the key whose
22098 certificate is @code{cert}.
22100 Defaults to @samp{"/etc/openvpn/client.key"}.
22104 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
22105 Whether to use the lzo compression algorithm.
22107 Defaults to @samp{#t}.
22111 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
22112 Don't re-read key files across SIGUSR1 or --ping-restart.
22114 Defaults to @samp{#t}.
22118 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
22119 Don't close and reopen TUN/TAP device or run up/down scripts across
22120 SIGUSR1 or --ping-restart restarts.
22122 Defaults to @samp{#t}.
22126 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
22127 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22128 poll/epoll/select prior to the write operation.
22130 Defaults to @samp{#f}.
22133 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
22136 Defaults to @samp{3}.
22140 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
22141 Add an additional layer of HMAC authentication on top of the TLS control
22142 channel to protect against DoS attacks.
22144 Defaults to @samp{#f}.
22148 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
22149 Authenticate with server using username/password. The option is a file
22150 containing username/password on 2 lines. Do not use a file-like object as it
22151 would be added to the store and readable by any user.
22153 Defaults to @samp{'disabled}.
22156 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
22157 Whether to check the server certificate has server usage extension.
22159 Defaults to @samp{#t}.
22163 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
22164 Bind to a specific local port number.
22166 Defaults to @samp{#f}.
22170 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
22171 Retry resolving server address.
22173 Defaults to @samp{#t}.
22177 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
22178 A list of remote servers to connect to.
22180 Defaults to @samp{()}.
22182 Available @code{openvpn-remote-configuration} fields are:
22184 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
22187 Defaults to @samp{"my-server"}.
22191 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
22192 Port number the server listens to.
22194 Defaults to @samp{1194}.
22199 @c %end of automatic openvpn-client documentation
22201 @c %automatically generated documentation
22203 Available @code{openvpn-server-configuration} fields are:
22205 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
22206 The OpenVPN package.
22210 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
22211 The OpenVPN pid file.
22213 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22217 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
22218 The protocol (UDP or TCP) used to open a channel between clients and
22221 Defaults to @samp{udp}.
22225 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
22226 The device type used to represent the VPN connection.
22228 Defaults to @samp{tun}.
22232 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
22233 The certificate authority to check connections against.
22235 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22239 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
22240 The certificate of the machine the daemon is running on. It should be
22241 signed by the authority given in @code{ca}.
22243 Defaults to @samp{"/etc/openvpn/client.crt"}.
22247 @deftypevr {@code{openvpn-server-configuration} parameter} string key
22248 The key of the machine the daemon is running on. It must be the key whose
22249 certificate is @code{cert}.
22251 Defaults to @samp{"/etc/openvpn/client.key"}.
22255 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
22256 Whether to use the lzo compression algorithm.
22258 Defaults to @samp{#t}.
22262 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
22263 Don't re-read key files across SIGUSR1 or --ping-restart.
22265 Defaults to @samp{#t}.
22269 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
22270 Don't close and reopen TUN/TAP device or run up/down scripts across
22271 SIGUSR1 or --ping-restart restarts.
22273 Defaults to @samp{#t}.
22277 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
22278 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22279 poll/epoll/select prior to the write operation.
22281 Defaults to @samp{#f}.
22284 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
22287 Defaults to @samp{3}.
22291 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
22292 Add an additional layer of HMAC authentication on top of the TLS control
22293 channel to protect against DoS attacks.
22295 Defaults to @samp{#f}.
22299 @deftypevr {@code{openvpn-server-configuration} parameter} number port
22300 Specifies the port number on which the server listens.
22302 Defaults to @samp{1194}.
22306 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
22307 An ip and mask specifying the subnet inside the virtual network.
22309 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
22313 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
22314 A CIDR notation specifying the IPv6 subnet inside the virtual network.
22316 Defaults to @samp{#f}.
22320 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
22321 The Diffie-Hellman parameters file.
22323 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
22327 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
22328 The file that records client IPs.
22330 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
22334 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
22335 When true, the server will act as a gateway for its clients.
22337 Defaults to @samp{#f}.
22341 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
22342 When true, clients are allowed to talk to each other inside the VPN.
22344 Defaults to @samp{#f}.
22348 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
22349 Causes ping-like messages to be sent back and forth over the link so
22350 that each side knows when the other side has gone down. @code{keepalive}
22351 requires a pair. The first element is the period of the ping sending,
22352 and the second element is the timeout before considering the other side
22357 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
22358 The maximum number of clients.
22360 Defaults to @samp{100}.
22364 @deftypevr {@code{openvpn-server-configuration} parameter} string status
22365 The status file. This file shows a small report on current connection.
22366 It is truncated and rewritten every minute.
22368 Defaults to @samp{"/var/run/openvpn/status"}.
22372 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
22373 The list of configuration for some clients.
22375 Defaults to @samp{()}.
22377 Available @code{openvpn-ccd-configuration} fields are:
22379 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
22382 Defaults to @samp{"client"}.
22386 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
22389 Defaults to @samp{#f}.
22393 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
22396 Defaults to @samp{#f}.
22403 @c %end of automatic openvpn-server documentation
22406 @node Network File System
22407 @subsection Network File System
22410 The @code{(gnu services nfs)} module provides the following services,
22411 which are most commonly used in relation to mounting or exporting
22412 directory trees as @dfn{network file systems} (NFS).
22414 While it is possible to use the individual components that together make
22415 up a Network File System service, we recommended to configure an NFS
22416 server with the @code{nfs-service-type}.
22418 @subsubheading NFS Service
22419 @cindex NFS, server
22421 The NFS service takes care of setting up all NFS component services,
22422 kernel configuration file systems, and installs configuration files in
22423 the locations that NFS expects.
22425 @defvr {Scheme Variable} nfs-service-type
22426 A service type for a complete NFS server.
22429 @deftp {Data Type} nfs-configuration
22430 This data type represents the configuration of the NFS service and all
22433 It has the following parameters:
22435 @item @code{nfs-utils} (default: @code{nfs-utils})
22436 The nfs-utils package to use.
22438 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
22439 If a list of string values is provided, the @command{rpc.nfsd} daemon
22440 will be limited to supporting the given versions of the NFS protocol.
22442 @item @code{exports} (default: @code{'()})
22443 This is a list of directories the NFS server should export. Each entry
22444 is a list consisting of two elements: a directory name and a string
22445 containing all options. This is an example in which the directory
22446 @file{/export} is served to all NFS clients as a read-only share:
22452 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
22455 @item @code{rpcmountd-port} (default: @code{#f})
22456 The network port that the @command{rpc.mountd} daemon should use.
22458 @item @code{rpcstatd-port} (default: @code{#f})
22459 The network port that the @command{rpc.statd} daemon should use.
22461 @item @code{rpcbind} (default: @code{rpcbind})
22462 The rpcbind package to use.
22464 @item @code{idmap-domain} (default: @code{"localdomain"})
22465 The local NFSv4 domain name.
22467 @item @code{nfsd-port} (default: @code{2049})
22468 The network port that the @command{nfsd} daemon should use.
22470 @item @code{nfsd-threads} (default: @code{8})
22471 The number of threads used by the @command{nfsd} daemon.
22473 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22474 The directory where the pipefs file system is mounted.
22476 @item @code{debug} (default: @code{'()"})
22477 A list of subsystems for which debugging output should be enabled. This
22478 is a list of symbols. Any of these symbols are valid: @code{nfsd},
22479 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
22483 If you don't need a complete NFS service or prefer to build it yourself
22484 you can use the individual component services that are documented below.
22486 @subsubheading RPC Bind Service
22489 The RPC Bind service provides a facility to map program numbers into
22490 universal addresses.
22491 Many NFS related services use this facility. Hence it is automatically
22492 started when a dependent service starts.
22494 @defvr {Scheme Variable} rpcbind-service-type
22495 A service type for the RPC portmapper daemon.
22499 @deftp {Data Type} rpcbind-configuration
22500 Data type representing the configuration of the RPC Bind Service.
22501 This type has the following parameters:
22503 @item @code{rpcbind} (default: @code{rpcbind})
22504 The rpcbind package to use.
22506 @item @code{warm-start?} (default: @code{#t})
22507 If this parameter is @code{#t}, then the daemon will read a
22508 state file on startup thus reloading state information saved by a previous
22514 @subsubheading Pipefs Pseudo File System
22518 The pipefs file system is used to transfer NFS related data
22519 between the kernel and user space programs.
22521 @defvr {Scheme Variable} pipefs-service-type
22522 A service type for the pipefs pseudo file system.
22525 @deftp {Data Type} pipefs-configuration
22526 Data type representing the configuration of the pipefs pseudo file system service.
22527 This type has the following parameters:
22529 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22530 The directory to which the file system is to be attached.
22535 @subsubheading GSS Daemon Service
22538 @cindex global security system
22540 The @dfn{global security system} (GSS) daemon provides strong security for RPC
22542 Before exchanging RPC requests an RPC client must establish a security
22543 context. Typically this is done using the Kerberos command @command{kinit}
22544 or automatically at login time using PAM services (@pxref{Kerberos Services}).
22546 @defvr {Scheme Variable} gss-service-type
22547 A service type for the Global Security System (GSS) daemon.
22550 @deftp {Data Type} gss-configuration
22551 Data type representing the configuration of the GSS daemon service.
22552 This type has the following parameters:
22554 @item @code{nfs-utils} (default: @code{nfs-utils})
22555 The package in which the @command{rpc.gssd} command is to be found.
22557 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22558 The directory where the pipefs file system is mounted.
22564 @subsubheading IDMAP Daemon Service
22566 @cindex name mapper
22568 The idmap daemon service provides mapping between user IDs and user names.
22569 Typically it is required in order to access file systems mounted via NFSv4.
22571 @defvr {Scheme Variable} idmap-service-type
22572 A service type for the Identity Mapper (IDMAP) daemon.
22575 @deftp {Data Type} idmap-configuration
22576 Data type representing the configuration of the IDMAP daemon service.
22577 This type has the following parameters:
22579 @item @code{nfs-utils} (default: @code{nfs-utils})
22580 The package in which the @command{rpc.idmapd} command is to be found.
22582 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22583 The directory where the pipefs file system is mounted.
22585 @item @code{domain} (default: @code{#f})
22586 The local NFSv4 domain name.
22587 This must be a string or @code{#f}.
22588 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
22590 @item @code{verbosity} (default: @code{0})
22591 The verbosity level of the daemon.
22596 @node Continuous Integration
22597 @subsection Continuous Integration
22599 @cindex continuous integration
22600 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
22601 continuous integration tool for Guix. It can be used both for development and
22602 for providing substitutes to others (@pxref{Substitutes}).
22604 The @code{(gnu services cuirass)} module provides the following service.
22606 @defvr {Scheme Procedure} cuirass-service-type
22607 The type of the Cuirass service. Its value must be a
22608 @code{cuirass-configuration} object, as described below.
22611 To add build jobs, you have to set the @code{specifications} field of the
22612 configuration. Here is an example of a service that polls the Guix repository
22613 and builds the packages from a manifest. Some of the packages are defined in
22614 the @code{"custom-packages"} input, which is the equivalent of
22615 @code{GUIX_PACKAGE_PATH}.
22618 (define %cuirass-specs
22620 '((#:name . "my-manifest")
22621 (#:load-path-inputs . ("guix"))
22622 (#:package-path-inputs . ("custom-packages"))
22623 (#:proc-input . "guix")
22624 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
22625 (#:proc . cuirass-jobs)
22626 (#:proc-args . ((subset . "manifests")
22627 (systems . ("x86_64-linux"))
22628 (manifests . (("config" . "guix/manifest.scm")))))
22629 (#:inputs . (((#:name . "guix")
22630 (#:url . "git://git.savannah.gnu.org/guix.git")
22631 (#:load-path . ".")
22632 (#:branch . "master")
22633 (#:no-compile? . #t))
22634 ((#:name . "config")
22635 (#:url . "https://git.example.org/config.git")
22636 (#:load-path . ".")
22637 (#:branch . "master")
22638 (#:no-compile? . #t))
22639 ((#:name . "custom-packages")
22640 (#:url . "https://git.example.org/custom-packages.git")
22641 (#:load-path . ".")
22642 (#:branch . "master")
22643 (#:no-compile? . #t)))))))
22645 (service cuirass-service-type
22646 (cuirass-configuration
22647 (specifications %cuirass-specs)))
22650 While information related to build jobs is located directly in the
22651 specifications, global settings for the @command{cuirass} process are
22652 accessible in other @code{cuirass-configuration} fields.
22654 @deftp {Data Type} cuirass-configuration
22655 Data type representing the configuration of Cuirass.
22658 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
22659 Location of the log file.
22661 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
22662 Location of the log file used by the web interface.
22664 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
22665 Location of the repository cache.
22667 @item @code{user} (default: @code{"cuirass"})
22668 Owner of the @code{cuirass} process.
22670 @item @code{group} (default: @code{"cuirass"})
22671 Owner's group of the @code{cuirass} process.
22673 @item @code{interval} (default: @code{60})
22674 Number of seconds between the poll of the repositories followed by the
22677 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
22678 Location of sqlite database which contains the build results and previously
22679 added specifications.
22681 @item @code{ttl} (default: @code{(* 30 24 3600)})
22682 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
22683 are registered for build results. This means that build results are protected
22684 from garbage collection for at least @var{ttl} seconds.
22686 @item @code{port} (default: @code{8081})
22687 Port number used by the HTTP server.
22689 @item @code{host} (default: @code{"localhost"})
22690 Listen on the network interface for @var{host}. The default is to
22691 accept connections from localhost.
22693 @item @code{specifications} (default: @code{#~'()})
22694 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
22695 where a specification is an association list
22696 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
22697 keys are keywords (@code{#:keyword-example}) as shown in the example
22700 @item @code{use-substitutes?} (default: @code{#f})
22701 This allows using substitutes to avoid building every dependencies of a job
22704 @item @code{one-shot?} (default: @code{#f})
22705 Only evaluate specifications and build derivations once.
22707 @item @code{fallback?} (default: @code{#f})
22708 When substituting a pre-built binary fails, fall back to building
22711 @item @code{extra-options} (default: @code{'()})
22712 Extra options to pass when running the Cuirass processes.
22714 @item @code{cuirass} (default: @code{cuirass})
22715 The Cuirass package to use.
22719 @node Power Management Services
22720 @subsection Power Management Services
22723 @cindex power management with TLP
22724 @subsubheading TLP daemon
22726 The @code{(gnu services pm)} module provides a Guix service definition
22727 for the Linux power management tool TLP.
22729 TLP enables various powersaving modes in userspace and kernel.
22730 Contrary to @code{upower-service}, it is not a passive,
22731 monitoring tool, as it will apply custom settings each time a new power
22732 source is detected. More information can be found at
22733 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
22735 @deffn {Scheme Variable} tlp-service-type
22736 The service type for the TLP tool. Its value should be a valid
22737 TLP configuration (see below). To use the default settings, simply
22740 (service tlp-service-type)
22744 By default TLP does not need much configuration but most TLP parameters
22745 can be tweaked using @code{tlp-configuration}.
22747 Each parameter definition is preceded by its type; for example,
22748 @samp{boolean foo} indicates that the @code{foo} parameter
22749 should be specified as a boolean. Types starting with
22750 @code{maybe-} denote parameters that won't show up in TLP config file
22751 when their value is @code{'disabled}.
22753 @c The following documentation was initially generated by
22754 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
22755 @c documentation is better, so we shouldn't hesitate to edit below as
22756 @c needed. However if the change you want to make to this documentation
22757 @c can be done in an automated way, it's probably easier to change
22758 @c (generate-documentation) than to make it below and have to deal with
22759 @c the churn as TLP updates.
22761 Available @code{tlp-configuration} fields are:
22763 @deftypevr {@code{tlp-configuration} parameter} package tlp
22768 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
22769 Set to true if you wish to enable TLP.
22771 Defaults to @samp{#t}.
22775 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
22776 Default mode when no power supply can be detected. Alternatives are AC
22779 Defaults to @samp{"AC"}.
22783 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
22784 Number of seconds Linux kernel has to wait after the disk goes idle,
22785 before syncing on AC.
22787 Defaults to @samp{0}.
22791 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
22792 Same as @code{disk-idle-ac} but on BAT mode.
22794 Defaults to @samp{2}.
22798 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
22799 Dirty pages flushing periodicity, expressed in seconds.
22801 Defaults to @samp{15}.
22805 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
22806 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
22808 Defaults to @samp{60}.
22812 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
22813 CPU frequency scaling governor on AC mode. With intel_pstate driver,
22814 alternatives are powersave and performance. With acpi-cpufreq driver,
22815 alternatives are ondemand, powersave, performance and conservative.
22817 Defaults to @samp{disabled}.
22821 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
22822 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
22824 Defaults to @samp{disabled}.
22828 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
22829 Set the min available frequency for the scaling governor on AC.
22831 Defaults to @samp{disabled}.
22835 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
22836 Set the max available frequency for the scaling governor on AC.
22838 Defaults to @samp{disabled}.
22842 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
22843 Set the min available frequency for the scaling governor on BAT.
22845 Defaults to @samp{disabled}.
22849 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
22850 Set the max available frequency for the scaling governor on BAT.
22852 Defaults to @samp{disabled}.
22856 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
22857 Limit the min P-state to control the power dissipation of the CPU, in AC
22858 mode. Values are stated as a percentage of the available performance.
22860 Defaults to @samp{disabled}.
22864 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
22865 Limit the max P-state to control the power dissipation of the CPU, in AC
22866 mode. Values are stated as a percentage of the available performance.
22868 Defaults to @samp{disabled}.
22872 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
22873 Same as @code{cpu-min-perf-on-ac} on BAT mode.
22875 Defaults to @samp{disabled}.
22879 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
22880 Same as @code{cpu-max-perf-on-ac} on BAT mode.
22882 Defaults to @samp{disabled}.
22886 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
22887 Enable CPU turbo boost feature on AC mode.
22889 Defaults to @samp{disabled}.
22893 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
22894 Same as @code{cpu-boost-on-ac?} on BAT mode.
22896 Defaults to @samp{disabled}.
22900 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
22901 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
22902 used under light load conditions.
22904 Defaults to @samp{#f}.
22908 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
22909 Same as @code{sched-powersave-on-ac?} but on BAT mode.
22911 Defaults to @samp{#t}.
22915 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
22916 Enable Linux kernel NMI watchdog.
22918 Defaults to @samp{#f}.
22922 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
22923 For Linux kernels with PHC patch applied, change CPU voltages. An
22924 example value would be @samp{"F:V F:V F:V F:V"}.
22926 Defaults to @samp{disabled}.
22930 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
22931 Set CPU performance versus energy saving policy on AC. Alternatives are
22932 performance, normal, powersave.
22934 Defaults to @samp{"performance"}.
22938 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
22939 Same as @code{energy-perf-policy-ac} but on BAT mode.
22941 Defaults to @samp{"powersave"}.
22945 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
22950 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
22951 Hard disk advanced power management level.
22955 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
22956 Same as @code{disk-apm-bat} but on BAT mode.
22960 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
22961 Hard disk spin down timeout. One value has to be specified for each
22962 declared hard disk.
22964 Defaults to @samp{disabled}.
22968 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
22969 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
22971 Defaults to @samp{disabled}.
22975 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
22976 Select IO scheduler for disk devices. One value has to be specified for
22977 each declared hard disk. Example alternatives are cfq, deadline and
22980 Defaults to @samp{disabled}.
22984 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
22985 SATA aggressive link power management (ALPM) level. Alternatives are
22986 min_power, medium_power, max_performance.
22988 Defaults to @samp{"max_performance"}.
22992 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
22993 Same as @code{sata-linkpwr-ac} but on BAT mode.
22995 Defaults to @samp{"min_power"}.
22999 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
23000 Exclude specified SATA host devices for link power management.
23002 Defaults to @samp{disabled}.
23006 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
23007 Enable Runtime Power Management for AHCI controller and disks on AC
23010 Defaults to @samp{disabled}.
23014 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
23015 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
23017 Defaults to @samp{disabled}.
23021 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
23022 Seconds of inactivity before disk is suspended.
23024 Defaults to @samp{15}.
23028 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
23029 PCI Express Active State Power Management level. Alternatives are
23030 default, performance, powersave.
23032 Defaults to @samp{"performance"}.
23036 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
23037 Same as @code{pcie-aspm-ac} but on BAT mode.
23039 Defaults to @samp{"powersave"}.
23043 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
23044 Radeon graphics clock speed level. Alternatives are low, mid, high,
23047 Defaults to @samp{"high"}.
23051 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
23052 Same as @code{radeon-power-ac} but on BAT mode.
23054 Defaults to @samp{"low"}.
23058 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
23059 Radeon dynamic power management method (DPM). Alternatives are battery,
23062 Defaults to @samp{"performance"}.
23066 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
23067 Same as @code{radeon-dpm-state-ac} but on BAT mode.
23069 Defaults to @samp{"battery"}.
23073 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
23074 Radeon DPM performance level. Alternatives are auto, low, high.
23076 Defaults to @samp{"auto"}.
23080 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
23081 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
23083 Defaults to @samp{"auto"}.
23087 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
23088 Wifi power saving mode.
23090 Defaults to @samp{#f}.
23094 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
23095 Same as @code{wifi-power-ac?} but on BAT mode.
23097 Defaults to @samp{#t}.
23101 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
23102 Disable wake on LAN.
23104 Defaults to @samp{#t}.
23108 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
23109 Timeout duration in seconds before activating audio power saving on
23110 Intel HDA and AC97 devices. A value of 0 disables power saving.
23112 Defaults to @samp{0}.
23116 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
23117 Same as @code{sound-powersave-ac} but on BAT mode.
23119 Defaults to @samp{1}.
23123 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
23124 Disable controller in powersaving mode on Intel HDA devices.
23126 Defaults to @samp{#t}.
23130 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
23131 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
23132 powered on again by releasing (and reinserting) the eject lever or by
23133 pressing the disc eject button on newer models.
23135 Defaults to @samp{#f}.
23139 @deftypevr {@code{tlp-configuration} parameter} string bay-device
23140 Name of the optical drive device to power off.
23142 Defaults to @samp{"sr0"}.
23146 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
23147 Runtime Power Management for PCI(e) bus devices. Alternatives are on
23150 Defaults to @samp{"on"}.
23154 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
23155 Same as @code{runtime-pm-ac} but on BAT mode.
23157 Defaults to @samp{"auto"}.
23161 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
23162 Runtime Power Management for all PCI(e) bus devices, except blacklisted
23165 Defaults to @samp{#t}.
23169 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
23170 Exclude specified PCI(e) device addresses from Runtime Power Management.
23172 Defaults to @samp{disabled}.
23176 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
23177 Exclude PCI(e) devices assigned to the specified drivers from Runtime
23182 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
23183 Enable USB autosuspend feature.
23185 Defaults to @samp{#t}.
23189 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
23190 Exclude specified devices from USB autosuspend.
23192 Defaults to @samp{disabled}.
23196 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
23197 Exclude WWAN devices from USB autosuspend.
23199 Defaults to @samp{#t}.
23203 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
23204 Include specified devices into USB autosuspend, even if they are already
23205 excluded by the driver or via @code{usb-blacklist-wwan?}.
23207 Defaults to @samp{disabled}.
23211 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
23212 Enable USB autosuspend before shutdown.
23214 Defaults to @samp{disabled}.
23218 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
23219 Restore radio device state (bluetooth, wifi, wwan) from previous
23220 shutdown on system startup.
23222 Defaults to @samp{#f}.
23227 @cindex CPU frequency scaling with thermald
23228 @subsubheading Thermald daemon
23230 The @code{(gnu services pm)} module provides an interface to
23231 thermald, a CPU frequency scaling service which helps prevent overheating.
23233 @defvr {Scheme Variable} thermald-service-type
23234 This is the service type for
23235 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
23236 Thermal Daemon, which is responsible for controlling the thermal state
23237 of processors and preventing overheating.
23240 @deftp {Data Type} thermald-configuration
23241 Data type representing the configuration of @code{thermald-service-type}.
23244 @item @code{ignore-cpuid-check?} (default: @code{#f})
23245 Ignore cpuid check for supported CPU models.
23247 @item @code{thermald} (default: @var{thermald})
23248 Package object of thermald.
23253 @node Audio Services
23254 @subsection Audio Services
23256 The @code{(gnu services audio)} module provides a service to start MPD
23257 (the Music Player Daemon).
23260 @subsubheading Music Player Daemon
23262 The Music Player Daemon (MPD) is a service that can play music while
23263 being controlled from the local machine or over the network by a variety
23266 The following example shows how one might run @code{mpd} as user
23267 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
23270 (service mpd-service-type
23276 @defvr {Scheme Variable} mpd-service-type
23277 The service type for @command{mpd}
23280 @deftp {Data Type} mpd-configuration
23281 Data type representing the configuration of @command{mpd}.
23284 @item @code{user} (default: @code{"mpd"})
23285 The user to run mpd as.
23287 @item @code{music-dir} (default: @code{"~/Music"})
23288 The directory to scan for music files.
23290 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
23291 The directory to store playlists.
23293 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
23294 The location of the music database.
23296 @item @code{state-file} (default: @code{"~/.mpd/state"})
23297 The location of the file that stores current MPD's state.
23299 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
23300 The location of the sticker database.
23302 @item @code{port} (default: @code{"6600"})
23303 The port to run mpd on.
23305 @item @code{address} (default: @code{"any"})
23306 The address that mpd will bind to. To use a Unix domain socket,
23307 an absolute path can be specified here.
23309 @item @code{outputs} (default: @code{"(list (mpd-output))"})
23310 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
23315 @deftp {Data Type} mpd-output
23316 Data type representing an @command{mpd} audio output.
23319 @item @code{name} (default: @code{"MPD"})
23320 The name of the audio output.
23322 @item @code{type} (default: @code{"pulse"})
23323 The type of audio output.
23325 @item @code{enabled?} (default: @code{#t})
23326 Specifies whether this audio output is enabled when MPD is started. By
23327 default, all audio outputs are enabled. This is just the default
23328 setting when there is no state file; with a state file, the previous
23331 @item @code{tags?} (default: @code{#t})
23332 If set to @code{#f}, then MPD will not send tags to this output. This
23333 is only useful for output plugins that can receive tags, for example the
23334 @code{httpd} output plugin.
23336 @item @code{always-on?} (default: @code{#f})
23337 If set to @code{#t}, then MPD attempts to keep this audio output always
23338 open. This may be useful for streaming servers, when you don’t want to
23339 disconnect all listeners even when playback is accidentally stopped.
23341 @item @code{mixer-type}
23342 This field accepts a symbol that specifies which mixer should be used
23343 for this audio output: the @code{hardware} mixer, the @code{software}
23344 mixer, the @code{null} mixer (allows setting the volume, but with no
23345 effect; this can be used as a trick to implement an external mixer
23346 External Mixer) or no mixer (@code{none}).
23348 @item @code{extra-options} (default: @code{'()"})
23349 An association list of option symbols to string values to be appended to
23350 the audio output configuration.
23355 The following example shows a configuration of @code{mpd} that provides
23356 an HTTP audio streaming output.
23359 (service mpd-service-type
23367 `((encoder . "vorbis")
23368 (port . "8080"))))))))
23372 @node Virtualization Services
23373 @subsection Virtualization services
23375 The @code{(gnu services virtualization)} module provides services for
23376 the libvirt and virtlog daemons, as well as other virtualization-related
23379 @subsubheading Libvirt daemon
23380 @code{libvirtd} is the server side daemon component of the libvirt
23381 virtualization management system. This daemon runs on host servers
23382 and performs required management tasks for virtualized guests.
23384 @deffn {Scheme Variable} libvirt-service-type
23385 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
23386 Its value must be a @code{libvirt-configuration}.
23389 (service libvirt-service-type
23390 (libvirt-configuration
23391 (unix-sock-group "libvirt")
23392 (tls-port "16555")))
23396 @c Auto-generated with (generate-libvirt-documentation)
23397 Available @code{libvirt-configuration} fields are:
23399 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
23404 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
23405 Flag listening for secure TLS connections on the public TCP/IP port.
23406 must set @code{listen} for this to have any effect.
23408 It is necessary to setup a CA and issue server certificates before using
23411 Defaults to @samp{#t}.
23415 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
23416 Listen for unencrypted TCP connections on the public TCP/IP port. must
23417 set @code{listen} for this to have any effect.
23419 Using the TCP socket requires SASL authentication by default. Only SASL
23420 mechanisms which support data encryption are allowed. This is
23421 DIGEST_MD5 and GSSAPI (Kerberos5)
23423 Defaults to @samp{#f}.
23427 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
23428 Port for accepting secure TLS connections This can be a port number, or
23431 Defaults to @samp{"16514"}.
23435 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
23436 Port for accepting insecure TCP connections This can be a port number,
23439 Defaults to @samp{"16509"}.
23443 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
23444 IP address or hostname used for client connections.
23446 Defaults to @samp{"0.0.0.0"}.
23450 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
23451 Flag toggling mDNS advertisement of the libvirt service.
23453 Alternatively can disable for all services on a host by stopping the
23456 Defaults to @samp{#f}.
23460 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
23461 Default mDNS advertisement name. This must be unique on the immediate
23464 Defaults to @samp{"Virtualization Host <hostname>"}.
23468 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
23469 UNIX domain socket group ownership. This can be used to allow a
23470 'trusted' set of users access to management capabilities without
23473 Defaults to @samp{"root"}.
23477 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
23478 UNIX socket permissions for the R/O socket. This is used for monitoring
23481 Defaults to @samp{"0777"}.
23485 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
23486 UNIX socket permissions for the R/W socket. Default allows only root.
23487 If PolicyKit is enabled on the socket, the default will change to allow
23488 everyone (eg, 0777)
23490 Defaults to @samp{"0770"}.
23494 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
23495 UNIX socket permissions for the admin socket. Default allows only owner
23496 (root), do not change it unless you are sure to whom you are exposing
23499 Defaults to @samp{"0777"}.
23503 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
23504 The directory in which sockets will be found/created.
23506 Defaults to @samp{"/var/run/libvirt"}.
23510 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
23511 Authentication scheme for UNIX read-only sockets. By default socket
23512 permissions allow anyone to connect
23514 Defaults to @samp{"polkit"}.
23518 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
23519 Authentication scheme for UNIX read-write sockets. By default socket
23520 permissions only allow root. If PolicyKit support was compiled into
23521 libvirt, the default will be to use 'polkit' auth.
23523 Defaults to @samp{"polkit"}.
23527 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
23528 Authentication scheme for TCP sockets. If you don't enable SASL, then
23529 all TCP traffic is cleartext. Don't do this outside of a dev/test
23532 Defaults to @samp{"sasl"}.
23536 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
23537 Authentication scheme for TLS sockets. TLS sockets already have
23538 encryption provided by the TLS layer, and limited authentication is done
23541 It is possible to make use of any SASL authentication mechanism as well,
23542 by using 'sasl' for this option
23544 Defaults to @samp{"none"}.
23548 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
23549 API access control scheme.
23551 By default an authenticated user is allowed access to all APIs. Access
23552 drivers can place restrictions on this.
23554 Defaults to @samp{()}.
23558 @deftypevr {@code{libvirt-configuration} parameter} string key-file
23559 Server key file path. If set to an empty string, then no private key is
23562 Defaults to @samp{""}.
23566 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
23567 Server key file path. If set to an empty string, then no certificate is
23570 Defaults to @samp{""}.
23574 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
23575 Server key file path. If set to an empty string, then no CA certificate
23578 Defaults to @samp{""}.
23582 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
23583 Certificate revocation list path. If set to an empty string, then no
23586 Defaults to @samp{""}.
23590 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
23591 Disable verification of our own server certificates.
23593 When libvirtd starts it performs some sanity checks against its own
23596 Defaults to @samp{#f}.
23600 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
23601 Disable verification of client certificates.
23603 Client certificate verification is the primary authentication mechanism.
23604 Any client which does not present a certificate signed by the CA will be
23607 Defaults to @samp{#f}.
23611 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
23612 Whitelist of allowed x509 Distinguished Name.
23614 Defaults to @samp{()}.
23618 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
23619 Whitelist of allowed SASL usernames. The format for username depends on
23620 the SASL authentication mechanism.
23622 Defaults to @samp{()}.
23626 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
23627 Override the compile time default TLS priority string. The default is
23628 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
23629 is desired for libvirt to deviate from the global default settings.
23631 Defaults to @samp{"NORMAL"}.
23635 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
23636 Maximum number of concurrent client connections to allow over all
23639 Defaults to @samp{5000}.
23643 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
23644 Maximum length of queue of connections waiting to be accepted by the
23645 daemon. Note, that some protocols supporting retransmission may obey
23646 this so that a later reattempt at connection succeeds.
23648 Defaults to @samp{1000}.
23652 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
23653 Maximum length of queue of accepted but not yet authenticated clients.
23654 Set this to zero to turn this feature off
23656 Defaults to @samp{20}.
23660 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
23661 Number of workers to start up initially.
23663 Defaults to @samp{5}.
23667 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
23668 Maximum number of worker threads.
23670 If the number of active clients exceeds @code{min-workers}, then more
23671 threads are spawned, up to max_workers limit. Typically you'd want
23672 max_workers to equal maximum number of clients allowed.
23674 Defaults to @samp{20}.
23678 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
23679 Number of priority workers. If all workers from above pool are stuck,
23680 some calls marked as high priority (notably domainDestroy) can be
23681 executed in this pool.
23683 Defaults to @samp{5}.
23687 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
23688 Total global limit on concurrent RPC calls.
23690 Defaults to @samp{20}.
23694 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
23695 Limit on concurrent requests from a single client connection. To avoid
23696 one client monopolizing the server this should be a small fraction of
23697 the global max_requests and max_workers parameter.
23699 Defaults to @samp{5}.
23703 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
23704 Same as @code{min-workers} but for the admin interface.
23706 Defaults to @samp{1}.
23710 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
23711 Same as @code{max-workers} but for the admin interface.
23713 Defaults to @samp{5}.
23717 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
23718 Same as @code{max-clients} but for the admin interface.
23720 Defaults to @samp{5}.
23724 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
23725 Same as @code{max-queued-clients} but for the admin interface.
23727 Defaults to @samp{5}.
23731 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
23732 Same as @code{max-client-requests} but for the admin interface.
23734 Defaults to @samp{5}.
23738 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
23739 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
23741 Defaults to @samp{3}.
23745 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
23748 A filter allows to select a different logging level for a given category
23749 of logs The format for a filter is one of:
23760 where @code{name} is a string which is matched against the category
23761 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
23762 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
23763 name in the filter can be a substring of the full category name, in
23764 order to match multiple similar categories), the optional @samp{"+"}
23765 prefix tells libvirt to log stack trace for each message matching name,
23766 and @code{x} is the minimal level where matching messages should be
23784 Multiple filters can be defined in a single filters statement, they just
23785 need to be separated by spaces.
23787 Defaults to @samp{"3:remote 4:event"}.
23791 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
23794 An output is one of the places to save logging information. The format
23795 for an output can be:
23799 output goes to stderr
23801 @item x:syslog:name
23802 use syslog for the output and use the given name as the ident
23804 @item x:file:file_path
23805 output to a file, with the given filepath
23808 output to journald logging system
23812 In all case the x prefix is the minimal level, acting as a filter
23829 Multiple outputs can be defined, they just need to be separated by
23832 Defaults to @samp{"3:stderr"}.
23836 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
23837 Allows usage of the auditing subsystem to be altered
23841 0: disable all auditing
23844 1: enable auditing, only if enabled on host
23847 2: enable auditing, and exit if disabled on host.
23851 Defaults to @samp{1}.
23855 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
23856 Send audit messages via libvirt logging infrastructure.
23858 Defaults to @samp{#f}.
23862 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
23863 Host UUID. UUID must not have all digits be the same.
23865 Defaults to @samp{""}.
23869 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
23870 Source to read host UUID.
23874 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
23877 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
23881 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
23884 Defaults to @samp{"smbios"}.
23888 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
23889 A keepalive message is sent to a client after @code{keepalive_interval}
23890 seconds of inactivity to check if the client is still responding. If
23891 set to -1, libvirtd will never send keepalive requests; however clients
23892 can still send them and the daemon will send responses.
23894 Defaults to @samp{5}.
23898 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
23899 Maximum number of keepalive messages that are allowed to be sent to the
23900 client without getting any response before the connection is considered
23903 In other words, the connection is automatically closed approximately
23904 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
23905 the last message received from the client. When @code{keepalive-count}
23906 is set to 0, connections will be automatically closed after
23907 @code{keepalive-interval} seconds of inactivity without sending any
23908 keepalive messages.
23910 Defaults to @samp{5}.
23914 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
23915 Same as above but for admin interface.
23917 Defaults to @samp{5}.
23921 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
23922 Same as above but for admin interface.
23924 Defaults to @samp{5}.
23928 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
23929 Timeout for Open vSwitch calls.
23931 The @code{ovs-vsctl} utility is used for the configuration and its
23932 timeout option is set by default to 5 seconds to avoid potential
23933 infinite waits blocking libvirt.
23935 Defaults to @samp{5}.
23939 @c %end of autogenerated docs
23941 @subsubheading Virtlog daemon
23942 The virtlogd service is a server side daemon component of libvirt that is
23943 used to manage logs from virtual machine consoles.
23945 This daemon is not used directly by libvirt client applications, rather it
23946 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
23947 standalone daemon, the main @code{libvirtd} daemon can be restarted without
23948 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
23949 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
23951 @deffn {Scheme Variable} virtlog-service-type
23952 This is the type of the virtlog daemon.
23953 Its value must be a @code{virtlog-configuration}.
23956 (service virtlog-service-type
23957 (virtlog-configuration
23958 (max-clients 1000)))
23962 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
23963 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
23965 Defaults to @samp{3}.
23969 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
23972 A filter allows to select a different logging level for a given category
23973 of logs The format for a filter is one of:
23984 where @code{name} is a string which is matched against the category
23985 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
23986 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
23987 be a substring of the full category name, in order to match multiple
23988 similar categories), the optional "+" prefix tells libvirt to log stack
23989 trace for each message matching name, and @code{x} is the minimal level
23990 where matching messages should be logged:
24007 Multiple filters can be defined in a single filters statement, they just
24008 need to be separated by spaces.
24010 Defaults to @samp{"3:remote 4:event"}.
24014 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
24017 An output is one of the places to save logging information The format
24018 for an output can be:
24022 output goes to stderr
24024 @item x:syslog:name
24025 use syslog for the output and use the given name as the ident
24027 @item x:file:file_path
24028 output to a file, with the given filepath
24031 output to journald logging system
24035 In all case the x prefix is the minimal level, acting as a filter
24052 Multiple outputs can be defined, they just need to be separated by
24055 Defaults to @samp{"3:stderr"}.
24059 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
24060 Maximum number of concurrent client connections to allow over all
24063 Defaults to @samp{1024}.
24067 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
24068 Maximum file size before rolling over.
24070 Defaults to @samp{2MB}
24074 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
24075 Maximum number of backup files to keep.
24077 Defaults to @samp{3}
24081 @subsubheading Transparent Emulation with QEMU
24084 @cindex @code{binfmt_misc}
24085 @code{qemu-binfmt-service-type} provides support for transparent
24086 emulation of program binaries built for different architectures---e.g.,
24087 it allows you to transparently execute an ARMv7 program on an x86_64
24088 machine. It achieves this by combining the @uref{https://www.qemu.org,
24089 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
24091 @defvr {Scheme Variable} qemu-binfmt-service-type
24092 This is the type of the QEMU/binfmt service for transparent emulation.
24093 Its value must be a @code{qemu-binfmt-configuration} object, which
24094 specifies the QEMU package to use as well as the architecture we want to
24098 (service qemu-binfmt-service-type
24099 (qemu-binfmt-configuration
24100 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
24103 In this example, we enable transparent emulation for the ARM and aarch64
24104 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
24105 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
24106 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
24109 @deftp {Data Type} qemu-binfmt-configuration
24110 This is the configuration for the @code{qemu-binfmt} service.
24113 @item @code{platforms} (default: @code{'()})
24114 The list of emulated QEMU platforms. Each item must be a @dfn{platform
24115 object} as returned by @code{lookup-qemu-platforms} (see below).
24117 @item @code{guix-support?} (default: @code{#f})
24118 When it is true, QEMU and all its dependencies are added to the build
24119 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
24120 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
24121 handlers to be used within the build environment, which in turn means
24122 that you can transparently build programs for another architecture.
24124 For example, let's suppose you're on an x86_64 machine and you have this
24128 (service qemu-binfmt-service-type
24129 (qemu-binfmt-configuration
24130 (platforms (lookup-qemu-platforms "arm"))
24131 (guix-support? #t)))
24137 guix build -s armhf-linux inkscape
24141 and it will build Inkscape for ARMv7 @emph{as if it were a native
24142 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
24143 if you'd like to test a package build for an architecture you don't have
24146 @item @code{qemu} (default: @code{qemu})
24147 The QEMU package to use.
24151 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
24152 Return the list of QEMU platform objects corresponding to
24153 @var{platforms}@dots{}. @var{platforms} must be a list of strings
24154 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
24155 @code{"mips64el"}, and so on.
24158 @deffn {Scheme Procedure} qemu-platform? @var{obj}
24159 Return true if @var{obj} is a platform object.
24162 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
24163 Return the name of @var{platform}---a string such as @code{"arm"}.
24166 @node Version Control Services
24167 @subsection Version Control Services
24169 The @code{(gnu services version-control)} module provides a service to
24170 allow remote access to local Git repositories. There are three options:
24171 the @code{git-daemon-service}, which provides access to repositories via
24172 the @code{git://} unsecured TCP-based protocol, extending the
24173 @code{nginx} web server to proxy some requests to
24174 @code{git-http-backend}, or providing a web interface with
24175 @code{cgit-service-type}.
24177 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
24179 Return a service that runs @command{git daemon}, a simple TCP server to
24180 expose repositories over the Git protocol for anonymous access.
24182 The optional @var{config} argument should be a
24183 @code{<git-daemon-configuration>} object, by default it allows read-only
24184 access to exported@footnote{By creating the magic file
24185 @file{git-daemon-export-ok} in the repository directory.} repositories under
24190 @deftp {Data Type} git-daemon-configuration
24191 Data type representing the configuration for @code{git-daemon-service}.
24194 @item @code{package} (default: @var{git})
24195 Package object of the Git distributed version control system.
24197 @item @code{export-all?} (default: @var{#f})
24198 Whether to allow access for all Git repositories, even if they do not
24199 have the @file{git-daemon-export-ok} file.
24201 @item @code{base-path} (default: @file{/srv/git})
24202 Whether to remap all the path requests as relative to the given path.
24203 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
24204 then if you later try to pull @code{git://example.com/hello.git}, git
24205 daemon will interpret the path as @code{/srv/git/hello.git}.
24207 @item @code{user-path} (default: @var{#f})
24208 Whether to allow @code{~user} notation to be used in requests. When
24209 specified with empty string, requests to @code{git://host/~alice/foo} is
24210 taken as a request to access @code{foo} repository in the home directory
24211 of user @code{alice}. If @var{(user-path "path")} is specified, the
24212 same request is taken as a request to access @code{path/foo} repository
24213 in the home directory of user @code{alice}.
24215 @item @code{listen} (default: @var{'()})
24216 Whether to listen on specific IP addresses or hostnames, defaults to
24219 @item @code{port} (default: @var{#f})
24220 Whether to listen on an alternative port, which defaults to 9418.
24222 @item @code{whitelist} (default: @var{'()})
24223 If not empty, only allow access to this list of directories.
24225 @item @code{extra-options} (default: @var{'()})
24226 Extra options will be passed to @code{git daemon}, please run
24227 @command{man git-daemon} for more information.
24232 The @code{git://} protocol lacks authentication. When you pull from a
24233 repository fetched via @code{git://}, you don't know whether the data you
24234 receive was modified or is even coming from the specified host, and your
24235 connection is subject to eavesdropping. It's better to use an authenticated
24236 and encrypted transport, such as @code{https}. Although Git allows you
24237 to serve repositories using unsophisticated file-based web servers,
24238 there is a faster protocol implemented by the @code{git-http-backend}
24239 program. This program is the back-end of a proper Git web service. It
24240 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
24241 on running the necessary @code{fcgiwrap} daemon.
24243 Guix has a separate configuration data type for serving Git repositories
24246 @deftp {Data Type} git-http-configuration
24247 Data type representing the configuration for @code{git-http-service}.
24250 @item @code{package} (default: @var{git})
24251 Package object of the Git distributed version control system.
24253 @item @code{git-root} (default: @file{/srv/git})
24254 Directory containing the Git repositories to expose to the world.
24256 @item @code{export-all?} (default: @var{#f})
24257 Whether to expose access for all Git repositories in @var{git-root},
24258 even if they do not have the @file{git-daemon-export-ok} file.
24260 @item @code{uri-path} (default: @file{/git/})
24261 Path prefix for Git access. With the default @code{/git/} prefix, this
24262 will map @code{http://@var{server}/git/@var{repo}.git} to
24263 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
24264 with this prefix are not passed on to this Git instance.
24266 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
24267 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
24272 There is no @code{git-http-service-type}, currently; instead you can
24273 create an @code{nginx-location-configuration} from a
24274 @code{git-http-configuration} and then add that location to a web
24277 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
24278 [config=(git-http-configuration)]
24279 Compute an @code{nginx-location-configuration} that corresponds to the
24280 given Git http configuration. An example nginx service definition to
24281 serve the default @file{/srv/git} over HTTPS might be:
24284 (service nginx-service-type
24285 (nginx-configuration
24288 (nginx-server-configuration
24289 (listen '("443 ssl"))
24290 (server-name "git.my-host.org")
24292 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
24293 (ssl-certificate-key
24294 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
24297 (git-http-nginx-location-configuration
24298 (git-http-configuration (uri-path "/"))))))))))
24301 This example assumes that you are using Let's Encrypt to get your TLS
24302 certificate. @xref{Certificate Services}. The default @code{certbot}
24303 service will redirect all HTTP traffic on @code{git.my-host.org} to
24304 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
24305 system services. @xref{Web Services}.
24308 @subsubheading Cgit Service
24310 @cindex Cgit service
24311 @cindex Git, web interface
24312 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
24313 repositories written in C.
24315 The following example will configure the service with default values.
24316 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
24319 (service cgit-service-type)
24322 The @code{file-object} type designates either a file-like object
24323 (@pxref{G-Expressions, file-like objects}) or a string.
24325 @c %start of fragment
24327 Available @code{cgit-configuration} fields are:
24329 @deftypevr {@code{cgit-configuration} parameter} package package
24334 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
24335 NGINX configuration.
24339 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
24340 Specifies a command which will be invoked to format the content of about
24341 pages (both top-level and for each repository).
24343 Defaults to @samp{""}.
24347 @deftypevr {@code{cgit-configuration} parameter} string agefile
24348 Specifies a path, relative to each repository path, which can be used to
24349 specify the date and time of the youngest commit in the repository.
24351 Defaults to @samp{""}.
24355 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
24356 Specifies a command that will be invoked for authenticating repository
24359 Defaults to @samp{""}.
24363 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
24364 Flag which, when set to @samp{age}, enables date ordering in the branch
24365 ref list, and when set @samp{name} enables ordering by branch name.
24367 Defaults to @samp{"name"}.
24371 @deftypevr {@code{cgit-configuration} parameter} string cache-root
24372 Path used to store the cgit cache entries.
24374 Defaults to @samp{"/var/cache/cgit"}.
24378 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
24379 Number which specifies the time-to-live, in minutes, for the cached
24380 version of repository pages accessed with a fixed SHA1.
24382 Defaults to @samp{-1}.
24386 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
24387 Number which specifies the time-to-live, in minutes, for the cached
24388 version of repository pages accessed without a fixed SHA1.
24390 Defaults to @samp{5}.
24394 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
24395 Number which specifies the time-to-live, in minutes, for the cached
24396 version of the repository summary page.
24398 Defaults to @samp{5}.
24402 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
24403 Number which specifies the time-to-live, in minutes, for the cached
24404 version of the repository index page.
24406 Defaults to @samp{5}.
24410 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
24411 Number which specifies the time-to-live, in minutes, for the result of
24412 scanning a path for Git repositories.
24414 Defaults to @samp{15}.
24418 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
24419 Number which specifies the time-to-live, in minutes, for the cached
24420 version of the repository about page.
24422 Defaults to @samp{15}.
24426 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
24427 Number which specifies the time-to-live, in minutes, for the cached
24428 version of snapshots.
24430 Defaults to @samp{5}.
24434 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
24435 The maximum number of entries in the cgit cache. When set to @samp{0},
24436 caching is disabled.
24438 Defaults to @samp{0}.
24442 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
24443 Sort items in the repo list case sensitively.
24445 Defaults to @samp{#t}.
24449 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
24450 List of common prefixes which, when combined with a repository URL,
24451 generates valid clone URLs for the repository.
24453 Defaults to @samp{()}.
24457 @deftypevr {@code{cgit-configuration} parameter} list clone-url
24458 List of @code{clone-url} templates.
24460 Defaults to @samp{()}.
24464 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
24465 Command which will be invoked to format commit messages.
24467 Defaults to @samp{""}.
24471 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
24472 Flag which, when set to @samp{date}, enables strict date ordering in the
24473 commit log, and when set to @samp{topo} enables strict topological
24476 Defaults to @samp{"git log"}.
24480 @deftypevr {@code{cgit-configuration} parameter} file-object css
24481 URL which specifies the css document to include in all cgit pages.
24483 Defaults to @samp{"/share/cgit/cgit.css"}.
24487 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
24488 Specifies a command which will be invoked to format names and email
24489 address of committers, authors, and taggers, as represented in various
24490 places throughout the cgit interface.
24492 Defaults to @samp{""}.
24496 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
24497 Flag which, when set to @samp{#t}, will make cgit generate a HTML
24498 fragment suitable for embedding in other HTML pages.
24500 Defaults to @samp{#f}.
24504 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
24505 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
24506 commit history graph to the left of the commit messages in the
24507 repository log page.
24509 Defaults to @samp{#f}.
24513 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
24514 Flag which, when set to @samp{#t}, allows all filter settings to be
24515 overridden in repository-specific cgitrc files.
24517 Defaults to @samp{#f}.
24521 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
24522 Flag which, when set to @samp{#t}, allows users to follow a file in the
24525 Defaults to @samp{#f}.
24529 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
24530 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
24533 Defaults to @samp{#t}.
24537 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
24538 Flag which, when set to @samp{#t}, will make cgit generate extra links
24539 "summary", "commit", "tree" for each repo in the repository index.
24541 Defaults to @samp{#f}.
24545 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
24546 Flag which, when set to @samp{#t}, will make cgit display the owner of
24547 each repo in the repository index.
24549 Defaults to @samp{#t}.
24553 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
24554 Flag which, when set to @samp{#t}, will make cgit print the number of
24555 modified files for each commit on the repository log page.
24557 Defaults to @samp{#f}.
24561 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
24562 Flag which, when set to @samp{#t}, will make cgit print the number of
24563 added and removed lines for each commit on the repository log page.
24565 Defaults to @samp{#f}.
24569 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
24570 Flag which, when set to @code{#t}, will make cgit display remote
24571 branches in the summary and refs views.
24573 Defaults to @samp{#f}.
24577 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
24578 Flag which, when set to @code{1}, will make cgit use the subject of the
24579 parent commit as link text when generating links to parent commits in
24582 Defaults to @samp{#f}.
24586 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
24587 Flag which, when set to @samp{#t}, will make cgit use the subject of the
24588 parent commit as link text when generating links to parent commits in
24591 Defaults to @samp{#f}.
24595 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
24596 Flag which, when set to @samp{#t}, will make cgit generate linenumber
24597 links for plaintext blobs printed in the tree view.
24599 Defaults to @samp{#t}.
24603 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
24604 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
24605 set any repo specific settings.
24607 Defaults to @samp{#f}.
24611 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
24612 URL used as link to a shortcut icon for cgit.
24614 Defaults to @samp{"/favicon.ico"}.
24618 @deftypevr {@code{cgit-configuration} parameter} string footer
24619 The content of the file specified with this option will be included
24620 verbatim at the bottom of all pages (i.e.@: it replaces the standard
24621 "generated by..."@: message).
24623 Defaults to @samp{""}.
24627 @deftypevr {@code{cgit-configuration} parameter} string head-include
24628 The content of the file specified with this option will be included
24629 verbatim in the HTML HEAD section on all pages.
24631 Defaults to @samp{""}.
24635 @deftypevr {@code{cgit-configuration} parameter} string header
24636 The content of the file specified with this option will be included
24637 verbatim at the top of all pages.
24639 Defaults to @samp{""}.
24643 @deftypevr {@code{cgit-configuration} parameter} file-object include
24644 Name of a configfile to include before the rest of the current config-
24647 Defaults to @samp{""}.
24651 @deftypevr {@code{cgit-configuration} parameter} string index-header
24652 The content of the file specified with this option will be included
24653 verbatim above the repository index.
24655 Defaults to @samp{""}.
24659 @deftypevr {@code{cgit-configuration} parameter} string index-info
24660 The content of the file specified with this option will be included
24661 verbatim below the heading on the repository index page.
24663 Defaults to @samp{""}.
24667 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
24668 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
24669 in the servers timezone.
24671 Defaults to @samp{#f}.
24675 @deftypevr {@code{cgit-configuration} parameter} file-object logo
24676 URL which specifies the source of an image which will be used as a logo
24679 Defaults to @samp{"/share/cgit/cgit.png"}.
24683 @deftypevr {@code{cgit-configuration} parameter} string logo-link
24684 URL loaded when clicking on the cgit logo image.
24686 Defaults to @samp{""}.
24690 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
24691 Command which will be invoked to format the Owner column of the main
24694 Defaults to @samp{""}.
24698 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
24699 Number of items to display in atom feeds view.
24701 Defaults to @samp{10}.
24705 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
24706 Number of entries to list per page in "log" view.
24708 Defaults to @samp{50}.
24712 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
24713 Number of commit message characters to display in "log" view.
24715 Defaults to @samp{80}.
24719 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
24720 Specifies the number of entries to list per page on the repository index
24723 Defaults to @samp{50}.
24727 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
24728 Specifies the maximum number of repo description characters to display
24729 on the repository index page.
24731 Defaults to @samp{80}.
24735 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
24736 Specifies the maximum size of a blob to display HTML for in KBytes.
24738 Defaults to @samp{0}.
24742 @deftypevr {@code{cgit-configuration} parameter} string max-stats
24743 Maximum statistics period. Valid values are @samp{week},@samp{month},
24744 @samp{quarter} and @samp{year}.
24746 Defaults to @samp{""}.
24750 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
24751 Mimetype for the specified filename extension.
24753 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
24754 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
24755 "image/png") (svg "image/svg+xml"))}.
24759 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
24760 Specifies the file to use for automatic mimetype lookup.
24762 Defaults to @samp{""}.
24766 @deftypevr {@code{cgit-configuration} parameter} string module-link
24767 Text which will be used as the formatstring for a hyperlink when a
24768 submodule is printed in a directory listing.
24770 Defaults to @samp{""}.
24774 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
24775 If set to the value @samp{#t} caching will be disabled.
24777 Defaults to @samp{#f}.
24781 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
24782 If set to @samp{#t} showing full author email addresses will be
24785 Defaults to @samp{#f}.
24789 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
24790 Flag which, when set to @samp{#t}, will make cgit omit the standard
24791 header on all pages.
24793 Defaults to @samp{#f}.
24797 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
24798 A list of subdirectories inside of @code{repository-directory}, relative
24799 to it, that should loaded as Git repositories. An empty list means that
24800 all subdirectories will be loaded.
24802 Defaults to @samp{()}.
24806 @deftypevr {@code{cgit-configuration} parameter} file-object readme
24807 Text which will be used as default value for @code{cgit-repo-readme}.
24809 Defaults to @samp{""}.
24813 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
24814 If set to @code{#t} and @code{repository-directory} is enabled, if any
24815 repositories are found with a suffix of @code{.git}, this suffix will be
24816 removed for the URL and name.
24818 Defaults to @samp{#f}.
24822 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
24823 Maximum number of files to consider when detecting renames.
24825 Defaults to @samp{-1}.
24829 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
24830 The way in which repositories in each section are sorted.
24832 Defaults to @samp{""}.
24836 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
24837 Text used as content for the @code{robots} meta-tag.
24839 Defaults to @samp{("noindex" "nofollow")}.
24843 @deftypevr {@code{cgit-configuration} parameter} string root-desc
24844 Text printed below the heading on the repository index page.
24846 Defaults to @samp{"a fast webinterface for the git dscm"}.
24850 @deftypevr {@code{cgit-configuration} parameter} string root-readme
24851 The content of the file specified with this option will be included
24852 verbatim below the ``about'' link on the repository index page.
24854 Defaults to @samp{""}.
24858 @deftypevr {@code{cgit-configuration} parameter} string root-title
24859 Text printed as heading on the repository index page.
24861 Defaults to @samp{""}.
24865 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
24866 If set to @samp{#t} and repository-directory is enabled,
24867 repository-directory will recurse into directories whose name starts
24868 with a period. Otherwise, repository-directory will stay away from such
24869 directories, considered as ``hidden''. Note that this does not apply to
24870 the @file{.git} directory in non-bare repos.
24872 Defaults to @samp{#f}.
24876 @deftypevr {@code{cgit-configuration} parameter} list snapshots
24877 Text which specifies the default set of snapshot formats that cgit
24878 generates links for.
24880 Defaults to @samp{()}.
24884 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
24885 Name of the directory to scan for repositories (represents
24888 Defaults to @samp{"/srv/git"}.
24892 @deftypevr {@code{cgit-configuration} parameter} string section
24893 The name of the current repository section - all repositories defined
24894 after this option will inherit the current section name.
24896 Defaults to @samp{""}.
24900 @deftypevr {@code{cgit-configuration} parameter} string section-sort
24901 Flag which, when set to @samp{1}, will sort the sections on the
24902 repository listing by name.
24904 Defaults to @samp{""}.
24908 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
24909 A number which, if defined prior to repository-directory, specifies how
24910 many path elements from each repo path to use as a default section name.
24912 Defaults to @samp{0}.
24916 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
24917 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
24920 Defaults to @samp{#f}.
24924 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
24925 Specifies a command which will be invoked to format plaintext blobs in
24928 Defaults to @samp{""}.
24932 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
24933 Specifies the number of branches to display in the repository ``summary''
24936 Defaults to @samp{10}.
24940 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
24941 Specifies the number of log entries to display in the repository
24944 Defaults to @samp{10}.
24948 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
24949 Specifies the number of tags to display in the repository ``summary''
24952 Defaults to @samp{10}.
24956 @deftypevr {@code{cgit-configuration} parameter} string strict-export
24957 Filename which, if specified, needs to be present within the repository
24958 for cgit to allow access to that repository.
24960 Defaults to @samp{""}.
24964 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
24965 URL which, if specified, will be used as root for all cgit links.
24967 Defaults to @samp{"/"}.
24971 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
24972 A list of @dfn{cgit-repo} records to use with config.
24974 Defaults to @samp{()}.
24976 Available @code{repository-cgit-configuration} fields are:
24978 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
24979 A mask of snapshot formats for this repo that cgit generates links for,
24980 restricted by the global @code{snapshots} setting.
24982 Defaults to @samp{()}.
24986 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
24987 Override the default @code{source-filter}.
24989 Defaults to @samp{""}.
24993 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
24994 The relative URL used to access the repository.
24996 Defaults to @samp{""}.
25000 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
25001 Override the default @code{about-filter}.
25003 Defaults to @samp{""}.
25007 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
25008 Flag which, when set to @samp{age}, enables date ordering in the branch
25009 ref list, and when set to @samp{name} enables ordering by branch name.
25011 Defaults to @samp{""}.
25015 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
25016 A list of URLs which can be used to clone repo.
25018 Defaults to @samp{()}.
25022 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
25023 Override the default @code{commit-filter}.
25025 Defaults to @samp{""}.
25029 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
25030 Flag which, when set to @samp{date}, enables strict date ordering in the
25031 commit log, and when set to @samp{topo} enables strict topological
25034 Defaults to @samp{""}.
25038 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
25039 The name of the default branch for this repository. If no such branch
25040 exists in the repository, the first branch name (when sorted) is used as
25041 default instead. By default branch pointed to by HEAD, or ``master'' if
25042 there is no suitable HEAD.
25044 Defaults to @samp{""}.
25048 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
25049 The value to show as repository description.
25051 Defaults to @samp{""}.
25055 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
25056 The value to show as repository homepage.
25058 Defaults to @samp{""}.
25062 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
25063 Override the default @code{email-filter}.
25065 Defaults to @samp{""}.
25069 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
25070 A flag which can be used to disable the global setting
25071 @code{enable-commit-graph?}.
25073 Defaults to @samp{disabled}.
25077 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
25078 A flag which can be used to disable the global setting
25079 @code{enable-log-filecount?}.
25081 Defaults to @samp{disabled}.
25085 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
25086 A flag which can be used to disable the global setting
25087 @code{enable-log-linecount?}.
25089 Defaults to @samp{disabled}.
25093 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
25094 Flag which, when set to @code{#t}, will make cgit display remote
25095 branches in the summary and refs views.
25097 Defaults to @samp{disabled}.
25101 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
25102 A flag which can be used to override the global setting
25103 @code{enable-subject-links?}.
25105 Defaults to @samp{disabled}.
25109 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
25110 A flag which can be used to override the global setting
25111 @code{enable-html-serving?}.
25113 Defaults to @samp{disabled}.
25117 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
25118 Flag which, when set to @code{#t}, hides the repository from the
25121 Defaults to @samp{#f}.
25125 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
25126 Flag which, when set to @samp{#t}, ignores the repository.
25128 Defaults to @samp{#f}.
25132 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
25133 URL which specifies the source of an image which will be used as a logo
25134 on this repo’s pages.
25136 Defaults to @samp{""}.
25140 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
25141 URL loaded when clicking on the cgit logo image.
25143 Defaults to @samp{""}.
25147 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
25148 Override the default @code{owner-filter}.
25150 Defaults to @samp{""}.
25154 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
25155 Text which will be used as the formatstring for a hyperlink when a
25156 submodule is printed in a directory listing. The arguments for the
25157 formatstring are the path and SHA1 of the submodule commit.
25159 Defaults to @samp{""}.
25163 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
25164 Text which will be used as the formatstring for a hyperlink when a
25165 submodule with the specified subdirectory path is printed in a directory
25168 Defaults to @samp{()}.
25172 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
25173 Override the default maximum statistics period.
25175 Defaults to @samp{""}.
25179 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
25180 The value to show as repository name.
25182 Defaults to @samp{""}.
25186 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
25187 A value used to identify the owner of the repository.
25189 Defaults to @samp{""}.
25193 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
25194 An absolute path to the repository directory.
25196 Defaults to @samp{""}.
25200 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
25201 A path (relative to repo) which specifies a file to include verbatim as
25202 the ``About'' page for this repo.
25204 Defaults to @samp{""}.
25208 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
25209 The name of the current repository section - all repositories defined
25210 after this option will inherit the current section name.
25212 Defaults to @samp{""}.
25216 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
25217 Extra options will be appended to cgitrc file.
25219 Defaults to @samp{()}.
25225 @deftypevr {@code{cgit-configuration} parameter} list extra-options
25226 Extra options will be appended to cgitrc file.
25228 Defaults to @samp{()}.
25233 @c %end of fragment
25235 However, it could be that you just want to get a @code{cgitrc} up and
25236 running. In that case, you can pass an @code{opaque-cgit-configuration}
25237 as a record to @code{cgit-service-type}. As its name indicates, an
25238 opaque configuration does not have easy reflective capabilities.
25240 Available @code{opaque-cgit-configuration} fields are:
25242 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
25246 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
25247 The contents of the @code{cgitrc}, as a string.
25250 For example, if your @code{cgitrc} is just the empty string, you
25251 could instantiate a cgit service like this:
25254 (service cgit-service-type
25255 (opaque-cgit-configuration
25259 @subsubheading Gitolite Service
25261 @cindex Gitolite service
25262 @cindex Git, hosting
25263 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
25264 repositories on a central server.
25266 Gitolite can handle multiple repositories and users, and supports flexible
25267 configuration of the permissions for the users on the repositories.
25269 The following example will configure Gitolite using the default @code{git}
25270 user, and the provided SSH public key.
25273 (service gitolite-service-type
25274 (gitolite-configuration
25275 (admin-pubkey (plain-file
25277 "ssh-rsa AAAA... guix@@example.com"))))
25280 Gitolite is configured through a special admin repository which you can clone,
25281 for example, if you setup Gitolite on @code{example.com}, you would run the
25282 following command to clone the admin repository.
25285 git clone git@@example.com:gitolite-admin
25288 When the Gitolite service is activated, the provided @code{admin-pubkey} will
25289 be inserted in to the @file{keydir} directory in the gitolite-admin
25290 repository. If this results in a change in the repository, it will be
25291 committed using the message ``gitolite setup by GNU Guix''.
25293 @deftp {Data Type} gitolite-configuration
25294 Data type representing the configuration for @code{gitolite-service-type}.
25297 @item @code{package} (default: @var{gitolite})
25298 Gitolite package to use.
25300 @item @code{user} (default: @var{git})
25301 User to use for Gitolite. This will be user that you use when accessing
25304 @item @code{group} (default: @var{git})
25305 Group to use for Gitolite.
25307 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
25308 Directory in which to store the Gitolite configuration and repositories.
25310 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
25311 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
25312 representing the configuration for Gitolite.
25314 @item @code{admin-pubkey} (default: @var{#f})
25315 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
25316 setup Gitolite. This will be inserted in to the @file{keydir} directory
25317 within the gitolite-admin repository.
25319 To specify the SSH key as a string, use the @code{plain-file} function.
25322 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
25328 @deftp {Data Type} gitolite-rc-file
25329 Data type representing the Gitolite RC file.
25332 @item @code{umask} (default: @code{#o0077})
25333 This controls the permissions Gitolite sets on the repositories and their
25336 A value like @code{#o0027} will give read access to the group used by Gitolite
25337 (by default: @code{git}). This is necessary when using Gitolite with software
25338 like cgit or gitweb.
25340 @item @code{git-config-keys} (default: @code{""})
25341 Gitolite allows you to set git config values using the @samp{config} keyword. This
25342 setting allows control over the config keys to accept.
25344 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
25345 Set the role names allowed to be used by users running the perms command.
25347 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
25348 This setting controls the commands and features to enable within Gitolite.
25354 @node Game Services
25355 @subsection Game Services
25357 @subsubheading The Battle for Wesnoth Service
25359 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
25360 based tactical strategy game, with several single player campaigns, and
25361 multiplayer games (both networked and local).
25363 @defvar {Scheme Variable} wesnothd-service-type
25364 Service type for the wesnothd service. Its value must be a
25365 @code{wesnothd-configuration} object. To run wesnothd in the default
25366 configuration, instantiate it as:
25369 (service wesnothd-service-type)
25373 @deftp {Data Type} wesnothd-configuration
25374 Data type representing the configuration of @command{wesnothd}.
25377 @item @code{package} (default: @code{wesnoth-server})
25378 The wesnoth server package to use.
25380 @item @code{port} (default: @code{15000})
25381 The port to bind the server to.
25386 @node PAM Mount Service
25387 @subsection PAM Mount Service
25390 The @code{(gnu services pam-mount)} module provides a service allowing
25391 users to mount volumes when they log in. It should be able to mount any
25392 volume format supported by the system.
25394 @defvar {Scheme Variable} pam-mount-service-type
25395 Service type for PAM Mount support.
25398 @deftp {Data Type} pam-mount-configuration
25399 Data type representing the configuration of PAM Mount.
25401 It takes the following parameters:
25405 The configuration rules that will be used to generate
25406 @file{/etc/security/pam_mount.conf.xml}.
25408 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
25409 Guile Reference Manual}), and the the default ones don't mount anything
25410 for anyone at login:
25413 `((debug (@@ (enable "0")))
25414 (mntoptions (@@ (allow ,(string-join
25415 '("nosuid" "nodev" "loop"
25416 "encryption" "fsck" "nonempty"
25417 "allow_root" "allow_other")
25419 (mntoptions (@@ (require "nosuid,nodev")))
25420 (logout (@@ (wait "0")
25424 (mkmountpoint (@@ (enable "1")
25428 Some @code{volume} elements must be added to automatically mount volumes
25429 at login. Here's an example allowing the user @code{alice} to mount her
25430 encrypted @code{HOME} directory and allowing the user @code{bob} to mount
25431 the partition where he stores his data:
25434 (define pam-mount-rules
25435 `((debug (@@ (enable "0")))
25436 (volume (@@ (user "alice")
25439 (mountpoint "/home/alice")))
25440 (volume (@@ (user "bob")
25443 (mountpoint "/home/bob/data")
25444 (options "defaults,autodefrag,compress")))
25445 (mntoptions (@@ (allow ,(string-join
25446 '("nosuid" "nodev" "loop"
25447 "encryption" "fsck" "nonempty"
25448 "allow_root" "allow_other")
25450 (mntoptions (@@ (require "nosuid,nodev")))
25451 (logout (@@ (wait "0")
25455 (mkmountpoint (@@ (enable "1")
25456 (remove "true")))))
25458 (service pam-mount-service-type
25459 (pam-mount-configuration
25460 (rules pam-mount-rules)))
25463 The complete list of possible options can be found in the man page for
25464 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
25469 @node Guix Services
25470 @subsection Guix Services
25472 @subsubheading Guix Data Service
25473 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
25474 and provides data about GNU Guix. This includes information about
25475 packages, derivations and lint warnings.
25477 The data is stored in a PostgreSQL database, and available through a web
25480 @defvar {Scheme Variable} guix-data-service-type
25481 Service type for the Guix Data Service. Its value must be a
25482 @code{guix-data-service-configuration} object. The service optionally
25483 extends the getmail service, as the guix-commits mailing list is used to
25484 find out about changes in the Guix git repository.
25487 @deftp {Data Type} guix-data-service-configuration
25488 Data type representing the configuration of the Guix Data Service.
25491 @item @code{package} (default: @code{guix-data-service})
25492 The Guix Data Service package to use.
25494 @item @code{user} (default: @code{"guix-data-service"})
25495 The system user to run the service as.
25497 @item @code{group} (default: @code{"guix-data-service"})
25498 The system group to run the service as.
25500 @item @code{port} (default: @code{8765})
25501 The port to bind the web service to.
25503 @item @code{host} (default: @code{"127.0.0.1"})
25504 The host to bind the web service to.
25506 @item @code{getmail-idle-mailboxes} (default: @code{#f})
25507 If set, this is the list of mailboxes that the getmail service will be
25508 configured to listen to.
25510 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
25511 If set, this is the @code{getmail-retriever-configuration} object with
25512 which to configure getmail to fetch mail from the guix-commits mailing
25515 @item @code{extra-options} (default: @var{'()})
25516 Extra command line options for @code{guix-data-service}.
25518 @item @code{extra-process-jobs-options} (default: @var{'()})
25519 Extra command line options for @code{guix-data-service-process-jobs}.
25524 @node Linux Services
25525 @subsection Linux Services
25528 @cindex out of memory killer
25530 @cindex early out of memory daemon
25531 @subsubheading Early OOM Service
25533 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
25534 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
25535 space and provides a more responsive and configurable alternative to the
25536 in-kernel OOM killer. It is useful to prevent the system from becoming
25537 unresponsive when it runs out of memory.
25539 @deffn {Scheme Variable} earlyoom-service-type
25540 The service type for running @command{earlyoom}, the Early OOM daemon.
25541 Its value must be a @code{earlyoom-configuration} object, described
25542 below. The service can be instantiated in its default configuration
25546 (service earlyoom-service-type)
25550 @deftp {Data Type} earlyoom-configuration
25551 This is the configuration record for the @code{earlyoom-service-type}.
25554 @item @code{earlyoom} (default: @var{earlyoom})
25555 The Earlyoom package to use.
25557 @item @code{minimum-available-memory} (default: @code{10})
25558 The threshold for the minimum @emph{available} memory, in percentages.
25560 @item @code{minimum-free-swap} (default: @code{10})
25561 The threshold for the minimum free swap memory, in percentages.
25563 @item @code{prefer-regexp} (default: @code{#f})
25564 A regular expression (as a string) to match the names of the processes
25565 that should be preferably killed.
25567 @item @code{avoid-regexp} (default: @code{#f})
25568 A regular expression (as a string) to match the names of the processes
25569 that should @emph{not} be killed.
25571 @item @code{memory-report-interval} (default: @code{0})
25572 The interval in seconds at which a memory report is printed. It is
25573 disabled by default.
25575 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
25576 A boolean indicating whether the positive adjustments set in
25577 @file{/proc/*/oom_score_adj}.
25579 @item @code{show-debug-messages?} (default: @code{#f})
25580 A boolean indicating whether debug messages should be printed. The logs
25581 are saved at @file{/var/log/earlyoom.log}.
25583 @item @code{send-notification-command} (default: @code{#f})
25584 This can be used to provide a custom command used for sending
25590 @cindex kernel module loader
25591 @subsubheading Kernel Module Loader Service
25593 The kernel module loader service allows one to load loadable kernel
25594 modules at boot. This is especially useful for modules that don't
25595 autoload and need to be manually loaded, as it's the case with
25598 @deffn {Scheme Variable} kernel-module-loader-service-type
25599 The service type for loading loadable kernel modules at boot with
25600 @command{modprobe}. Its value must be a list of strings representing
25601 module names. For example loading the drivers provided by
25602 @code{ddcci-driver-linux}, in debugging mode by passing some module
25603 parameters, can be done as follow:
25606 (use-modules (gnu) (gnu services))
25607 (use-package-modules linux)
25608 (use-service-modules linux)
25610 (define ddcci-config
25611 (plain-file "ddcci.conf"
25612 "options ddcci dyndbg delay=120"))
25616 (services (cons* (service kernel-module-loader-service-type
25617 '("ddcci" "ddcci_backlight"))
25618 (simple-service 'ddcci-config etc-service-type
25619 (list `("modprobe.d/ddcci.conf"
25622 (kernel-loadable-modules (list ddcci-driver-linux)))
25626 @node Miscellaneous Services
25627 @subsection Miscellaneous Services
25629 @cindex fingerprint
25630 @subsubheading Fingerprint Service
25632 The @code{(gnu services authentication)} module provides a DBus service to
25633 read and identify fingerprints via a fingerprint sensor.
25635 @defvr {Scheme Variable} fprintd-service-type
25636 The service type for @command{fprintd}, which provides the fingerprint
25637 reading capability.
25640 (service fprintd-service-type)
25645 @subsubheading System Control Service
25647 The @code{(gnu services sysctl)} provides a service to configure kernel
25648 parameters at boot.
25650 @defvr {Scheme Variable} sysctl-service-type
25651 The service type for @command{sysctl}, which modifies kernel parameters
25652 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
25656 (service sysctl-service-type
25657 (sysctl-configuration
25658 (settings '(("net.ipv4.ip_forward" . "1")))))
25662 @deftp {Data Type} sysctl-configuration
25663 The data type representing the configuration of @command{sysctl}.
25666 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
25667 The @command{sysctl} executable to use.
25669 @item @code{settings} (default: @code{'()})
25670 An association list specifies kernel parameters and their values.
25675 @subsubheading PC/SC Smart Card Daemon Service
25677 The @code{(gnu services security-token)} module provides the following service
25678 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
25679 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
25680 manager that coordinates communications with smart card readers, smart cards
25681 and cryptographic tokens that are connected to the system.
25683 @defvr {Scheme Variable} pcscd-service-type
25684 Service type for the @command{pcscd} service. Its value must be a
25685 @code{pcscd-configuration} object. To run pcscd in the default
25686 configuration, instantiate it as:
25689 (service pcscd-service-type)
25693 @deftp {Data Type} pcscd-configuration
25694 The data type representing the configuration of @command{pcscd}.
25697 @item @code{pcsc-lite} (default: @code{pcsc-lite})
25698 The pcsc-lite package that provides pcscd.
25699 @item @code{usb-drivers} (default: @code{(list ccid)})
25700 List of packages that provide USB drivers to pcscd. Drivers are expected to be
25701 under @file{pcsc/drivers} in the store directory of the package.
25706 @subsubheading Lirc Service
25708 The @code{(gnu services lirc)} module provides the following service.
25710 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
25711 [#:device #f] [#:driver #f] [#:config-file #f] @
25712 [#:extra-options '()]
25713 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
25714 decodes infrared signals from remote controls.
25716 Optionally, @var{device}, @var{driver} and @var{config-file}
25717 (configuration file name) may be specified. See @command{lircd} manual
25720 Finally, @var{extra-options} is a list of additional command-line options
25721 passed to @command{lircd}.
25725 @subsubheading Spice Service
25727 The @code{(gnu services spice)} module provides the following service.
25729 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
25730 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
25731 that enables sharing the clipboard with a vm and setting the guest display
25732 resolution when the graphical console window resizes.
25735 @cindex inputattach
25736 @subsubheading inputattach Service
25738 @cindex tablet input, for Xorg
25739 @cindex touchscreen input, for Xorg
25740 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
25741 use input devices such as Wacom tablets, touchscreens, or joysticks with the
25742 Xorg display server.
25744 @deffn {Scheme Variable} inputattach-service-type
25745 Type of a service that runs @command{inputattach} on a device and
25746 dispatches events from it.
25749 @deftp {Data Type} inputattach-configuration
25751 @item @code{device-type} (default: @code{"wacom"})
25752 The type of device to connect to. Run @command{inputattach --help}, from the
25753 @code{inputattach} package, to see the list of supported device types.
25755 @item @code{device} (default: @code{"/dev/ttyS0"})
25756 The device file to connect to the device.
25758 @item @code{baud-rate} (default: @code{#f})
25759 Baud rate to use for the serial connection.
25760 Should be a number or @code{#f}.
25762 @item @code{log-file} (default: @code{#f})
25763 If true, this must be the name of a file to log messages to.
25767 @subsubheading Dictionary Service
25769 The @code{(gnu services dict)} module provides the following service:
25771 @defvr {Scheme Variable} dicod-service-type
25772 This is the type of the service that runs the @command{dicod} daemon, an
25773 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
25776 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
25777 Return a service that runs the @command{dicod} daemon, an implementation
25778 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
25780 The optional @var{config} argument specifies the configuration for
25781 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
25782 default it serves the GNU Collaborative International Dictionary of English.
25784 You can add @command{open localhost} to your @file{~/.dico} file to make
25785 @code{localhost} the default server for @command{dico} client
25786 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
25789 @deftp {Data Type} dicod-configuration
25790 Data type representing the configuration of dicod.
25793 @item @code{dico} (default: @var{dico})
25794 Package object of the GNU Dico dictionary server.
25796 @item @code{interfaces} (default: @var{'("localhost")})
25797 This is the list of IP addresses and ports and possibly socket file
25798 names to listen to (@pxref{Server Settings, @code{listen} directive,,
25799 dico, GNU Dico Manual}).
25801 @item @code{handlers} (default: @var{'()})
25802 List of @code{<dicod-handler>} objects denoting handlers (module instances).
25804 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
25805 List of @code{<dicod-database>} objects denoting dictionaries to be served.
25809 @deftp {Data Type} dicod-handler
25810 Data type representing a dictionary handler (module instance).
25814 Name of the handler (module instance).
25816 @item @code{module} (default: @var{#f})
25817 Name of the dicod module of the handler (instance). If it is @code{#f},
25818 the module has the same name as the handler.
25819 (@pxref{Modules,,, dico, GNU Dico Manual}).
25821 @item @code{options}
25822 List of strings or gexps representing the arguments for the module handler
25826 @deftp {Data Type} dicod-database
25827 Data type representing a dictionary database.
25831 Name of the database, will be used in DICT commands.
25833 @item @code{handler}
25834 Name of the dicod handler (module instance) used by this database
25835 (@pxref{Handlers,,, dico, GNU Dico Manual}).
25837 @item @code{complex?} (default: @var{#f})
25838 Whether the database configuration complex. The complex configuration
25839 will need a corresponding @code{<dicod-handler>} object, otherwise not.
25841 @item @code{options}
25842 List of strings or gexps representing the arguments for the database
25843 (@pxref{Databases,,, dico, GNU Dico Manual}).
25847 @defvr {Scheme Variable} %dicod-database:gcide
25848 A @code{<dicod-database>} object serving the GNU Collaborative International
25849 Dictionary of English using the @code{gcide} package.
25852 The following is an example @code{dicod-service} configuration.
25855 (dicod-service #:config
25856 (dicod-configuration
25857 (handlers (list (dicod-handler
25861 (list #~(string-append "dbdir=" #$wordnet))))))
25862 (databases (list (dicod-database
25865 (handler "wordnet")
25866 (options '("database=wn")))
25867 %dicod-database:gcide))))
25871 @subsubheading Docker Service
25873 The @code{(gnu services docker)} module provides the following services.
25875 @defvr {Scheme Variable} docker-service-type
25877 This is the type of the service that runs @url{https://www.docker.com,Docker},
25878 a daemon that can execute application bundles (sometimes referred to as
25879 ``containers'') in isolated environments.
25883 @deftp {Data Type} docker-configuration
25884 This is the data type representing the configuration of Docker and Containerd.
25888 @item @code{package} (default: @code{docker})
25889 The Docker package to use.
25891 @item @code{containerd} (default: @var{containerd})
25892 The Containerd package to use.
25898 @subsubheading Auditd Service
25900 The @code{(gnu services auditd)} module provides the following service.
25902 @defvr {Scheme Variable} auditd-service-type
25904 This is the type of the service that runs
25905 @url{https://people.redhat.com/sgrubb/audit/,auditd},
25906 a daemon that tracks security-relevant information on your system.
25908 Examples of things that can be tracked:
25918 Failed login attempts
25925 @command{auditctl} from the @code{audit} package can be used in order
25926 to add or remove events to be tracked (until the next reboot).
25927 In order to permanently track events, put the command line arguments
25928 of auditctl into @file{/etc/audit/audit.rules}.
25929 @command{aureport} from the @code{audit} package can be used in order
25930 to view a report of all recorded events.
25931 The audit daemon usually logs into the directory @file{/var/log/audit}.
25935 @deftp {Data Type} auditd-configuration
25936 This is the data type representing the configuration of auditd.
25940 @item @code{audit} (default: @code{audit})
25941 The audit package to use.
25946 @defvr {Scheme Variable} singularity-service-type
25947 This is the type of the service that allows you to run
25948 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
25949 create and run application bundles (aka. ``containers''). The value for this
25950 service is the Singularity package to use.
25952 The service does not install a daemon; instead, it installs helper programs as
25953 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
25954 @command{singularity run} and similar commands.
25958 @subsubheading Nix service
25960 The @code{(gnu services nix)} module provides the following service.
25962 @defvr {Scheme Variable} nix-service-type
25964 This is the type of the service that runs build daemon of the
25965 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
25969 (use-modules (gnu))
25970 (use-service-modules nix)
25971 (use-package-modules package-management)
25975 (packages (append (list nix)
25978 (services (append (list (service nix-service-type))
25982 After @command{guix system reconfigure} configure Nix for your user:
25985 @item Add a Nix channel and update it. See
25986 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
25988 @item Create a symlink to your profile and activate Nix profile:
25992 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
25993 $ source /run/current-system/profile/etc/profile.d/nix.sh
25998 @node Setuid Programs
25999 @section Setuid Programs
26001 @cindex setuid programs
26002 Some programs need to run with ``root'' privileges, even when they are
26003 launched by unprivileged users. A notorious example is the
26004 @command{passwd} program, which users can run to change their
26005 password, and which needs to access the @file{/etc/passwd} and
26006 @file{/etc/shadow} files---something normally restricted to root, for
26007 obvious security reasons. To address that, these executables are
26008 @dfn{setuid-root}, meaning that they always run with root privileges
26009 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
26010 for more info about the setuid mechanism.)
26012 The store itself @emph{cannot} contain setuid programs: that would be a
26013 security issue since any user on the system can write derivations that
26014 populate the store (@pxref{The Store}). Thus, a different mechanism is
26015 used: instead of changing the setuid bit directly on files that are in
26016 the store, we let the system administrator @emph{declare} which programs
26017 should be setuid root.
26019 The @code{setuid-programs} field of an @code{operating-system}
26020 declaration contains a list of G-expressions denoting the names of
26021 programs to be setuid-root (@pxref{Using the Configuration System}).
26022 For instance, the @command{passwd} program, which is part of the Shadow
26023 package, can be designated by this G-expression (@pxref{G-Expressions}):
26026 #~(string-append #$shadow "/bin/passwd")
26029 A default set of setuid programs is defined by the
26030 @code{%setuid-programs} variable of the @code{(gnu system)} module.
26032 @defvr {Scheme Variable} %setuid-programs
26033 A list of G-expressions denoting common programs that are setuid-root.
26035 The list includes commands such as @command{passwd}, @command{ping},
26036 @command{su}, and @command{sudo}.
26039 Under the hood, the actual setuid programs are created in the
26040 @file{/run/setuid-programs} directory at system activation time. The
26041 files in this directory refer to the ``real'' binaries, which are in the
26044 @node X.509 Certificates
26045 @section X.509 Certificates
26047 @cindex HTTPS, certificates
26048 @cindex X.509 certificates
26050 Web servers available over HTTPS (that is, HTTP over the transport-layer
26051 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
26052 that the client can then use to @emph{authenticate} the server. To do
26053 that, clients verify that the server's certificate is signed by a
26054 so-called @dfn{certificate authority} (CA). But to verify the CA's
26055 signature, clients must have first acquired the CA's certificate.
26057 Web browsers such as GNU@tie{}IceCat include their own set of CA
26058 certificates, such that they are able to verify CA signatures
26061 However, most other programs that can talk HTTPS---@command{wget},
26062 @command{git}, @command{w3m}, etc.---need to be told where CA
26063 certificates can be found.
26065 @cindex @code{nss-certs}
26066 In Guix, this is done by adding a package that provides certificates
26067 to the @code{packages} field of the @code{operating-system} declaration
26068 (@pxref{operating-system Reference}). Guix includes one such package,
26069 @code{nss-certs}, which is a set of CA certificates provided as part of
26070 Mozilla's Network Security Services.
26072 Note that it is @emph{not} part of @code{%base-packages}, so you need to
26073 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
26074 most applications and libraries look for certificates by default, points
26075 to the certificates installed globally.
26077 Unprivileged users, including users of Guix on a foreign distro,
26078 can also install their own certificate package in
26079 their profile. A number of environment variables need to be defined so
26080 that applications and libraries know where to find them. Namely, the
26081 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
26082 variables. Some applications add their own environment variables; for
26083 instance, the Git version control system honors the certificate bundle
26084 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
26085 would typically run something like:
26088 $ guix install nss-certs
26089 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
26090 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
26091 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
26094 As another example, R requires the @code{CURL_CA_BUNDLE} environment
26095 variable to point to a certificate bundle, so you would have to run
26096 something like this:
26099 $ guix install nss-certs
26100 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
26103 For other applications you may want to look up the required environment
26104 variable in the relevant documentation.
26107 @node Name Service Switch
26108 @section Name Service Switch
26110 @cindex name service switch
26112 The @code{(gnu system nss)} module provides bindings to the
26113 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
26114 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
26115 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
26116 extended with new ``name'' lookup methods for system databases, which
26117 includes host names, service names, user accounts, and more (@pxref{Name
26118 Service Switch, System Databases and Name Service Switch,, libc, The GNU
26119 C Library Reference Manual}).
26121 The NSS configuration specifies, for each system database, which lookup
26122 method is to be used, and how the various methods are chained
26123 together---for instance, under which circumstances NSS should try the
26124 next method in the list. The NSS configuration is given in the
26125 @code{name-service-switch} field of @code{operating-system} declarations
26126 (@pxref{operating-system Reference, @code{name-service-switch}}).
26129 @cindex .local, host name lookup
26130 As an example, the declaration below configures the NSS to use the
26131 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
26132 back-end}, which supports host name lookups over multicast DNS (mDNS)
26133 for host names ending in @code{.local}:
26136 (name-service-switch
26137 (hosts (list %files ;first, check /etc/hosts
26139 ;; If the above did not succeed, try
26140 ;; with 'mdns_minimal'.
26142 (name "mdns_minimal")
26144 ;; 'mdns_minimal' is authoritative for
26145 ;; '.local'. When it returns "not found",
26146 ;; no need to try the next methods.
26147 (reaction (lookup-specification
26148 (not-found => return))))
26150 ;; Then fall back to DNS.
26154 ;; Finally, try with the "full" 'mdns'.
26159 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
26160 contains this configuration, so you will not have to type it if all you
26161 want is to have @code{.local} host lookup working.
26163 Note that, in this case, in addition to setting the
26164 @code{name-service-switch} of the @code{operating-system} declaration,
26165 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
26166 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
26167 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
26168 to the name service cache daemon (@pxref{Base Services,
26169 @code{nscd-service}}).
26171 For convenience, the following variables provide typical NSS
26174 @defvr {Scheme Variable} %default-nss
26175 This is the default name service switch configuration, a
26176 @code{name-service-switch} object.
26179 @defvr {Scheme Variable} %mdns-host-lookup-nss
26180 This is the name service switch configuration with support for host name
26181 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
26184 The reference for name service switch configuration is given below. It
26185 is a direct mapping of the configuration file format of the C library , so
26186 please refer to the C library manual for more information (@pxref{NSS
26187 Configuration File,,, libc, The GNU C Library Reference Manual}).
26188 Compared to the configuration file format of libc NSS, it has the advantage
26189 not only of adding this warm parenthetic feel that we like, but also
26190 static checks: you will know about syntax errors and typos as soon as you
26191 run @command{guix system}.
26193 @deftp {Data Type} name-service-switch
26195 This is the data type representation the configuration of libc's name
26196 service switch (NSS). Each field below represents one of the supported
26213 The system databases handled by the NSS. Each of these fields must be a
26214 list of @code{<name-service>} objects (see below).
26218 @deftp {Data Type} name-service
26220 This is the data type representing an actual name service and the
26221 associated lookup action.
26225 A string denoting the name service (@pxref{Services in the NSS
26226 configuration,,, libc, The GNU C Library Reference Manual}).
26228 Note that name services listed here must be visible to nscd. This is
26229 achieved by passing the @code{#:name-services} argument to
26230 @code{nscd-service} the list of packages providing the needed name
26231 services (@pxref{Base Services, @code{nscd-service}}).
26234 An action specified using the @code{lookup-specification} macro
26235 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
26236 Reference Manual}). For example:
26239 (lookup-specification (unavailable => continue)
26240 (success => return))
26245 @node Initial RAM Disk
26246 @section Initial RAM Disk
26249 @cindex initial RAM disk
26250 For bootstrapping purposes, the Linux-Libre kernel is passed an
26251 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
26252 root file system as well as an initialization script. The latter is
26253 responsible for mounting the real root file system, and for loading any
26254 kernel modules that may be needed to achieve that.
26256 The @code{initrd-modules} field of an @code{operating-system}
26257 declaration allows you to specify Linux-libre kernel modules that must
26258 be available in the initrd. In particular, this is where you would list
26259 modules needed to actually drive the hard disk where your root partition
26260 is---although the default value of @code{initrd-modules} should cover
26261 most use cases. For example, assuming you need the @code{megaraid_sas}
26262 module in addition to the default modules to be able to access your root
26263 file system, you would write:
26268 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
26271 @defvr {Scheme Variable} %base-initrd-modules
26272 This is the list of kernel modules included in the initrd by default.
26275 Furthermore, if you need lower-level customization, the @code{initrd}
26276 field of an @code{operating-system} declaration allows
26277 you to specify which initrd you would like to use. The @code{(gnu
26278 system linux-initrd)} module provides three ways to build an initrd: the
26279 high-level @code{base-initrd} procedure and the low-level
26280 @code{raw-initrd} and @code{expression->initrd} procedures.
26282 The @code{base-initrd} procedure is intended to cover most common uses.
26283 For example, if you want to add a bunch of kernel modules to be loaded
26284 at boot time, you can define the @code{initrd} field of the operating
26285 system declaration like this:
26288 (initrd (lambda (file-systems . rest)
26289 ;; Create a standard initrd but set up networking
26290 ;; with the parameters QEMU expects by default.
26291 (apply base-initrd file-systems
26292 #:qemu-networking? #t
26296 The @code{base-initrd} procedure also handles common use cases that
26297 involves using the system as a QEMU guest, or as a ``live'' system with
26298 volatile root file system.
26300 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
26301 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
26302 such as trying to guess which kernel modules and packages should be included
26303 to the initrd. An example use of @code{raw-initrd} is when a user has
26304 a custom Linux kernel configuration and default kernel modules included by
26305 @code{base-initrd} are not available.
26307 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
26308 honors several options passed on the Linux kernel command line
26309 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
26310 @code{-append} option of QEMU), notably:
26313 @item --load=@var{boot}
26314 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
26315 program, once it has mounted the root file system.
26317 Guix uses this option to yield control to a boot program that runs the
26318 service activation programs and then spawns the GNU@tie{}Shepherd, the
26319 initialization system.
26321 @item --root=@var{root}
26322 Mount @var{root} as the root file system. @var{root} can be a
26323 device name like @code{/dev/sda1}, a file system label, or a file system
26326 @item --system=@var{system}
26327 Have @file{/run/booted-system} and @file{/run/current-system} point to
26330 @item modprobe.blacklist=@var{modules}@dots{}
26331 @cindex module, black-listing
26332 @cindex black list, of kernel modules
26333 Instruct the initial RAM disk as well as the @command{modprobe} command
26334 (from the kmod package) to refuse to load @var{modules}. @var{modules}
26335 must be a comma-separated list of module names---e.g.,
26336 @code{usbkbd,9pnet}.
26339 Start a read-eval-print loop (REPL) from the initial RAM disk before it
26340 tries to load kernel modules and to mount the root file system. Our
26341 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
26342 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
26343 Manual}, for more information on Guile's REPL.
26347 Now that you know all the features that initial RAM disks produced by
26348 @code{base-initrd} and @code{raw-initrd} provide,
26349 here is how to use it and customize it further.
26352 @cindex initial RAM disk
26353 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
26354 [#:linux-modules '()] [#:mapped-devices '()] @
26355 [#:keyboard-layout #f] @
26356 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
26357 Return a derivation that builds a raw initrd. @var{file-systems} is
26358 a list of file systems to be mounted by the initrd, possibly in addition to
26359 the root file system specified on the kernel command line via @code{--root}.
26360 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
26361 @var{mapped-devices} is a list of device mappings to realize before
26362 @var{file-systems} are mounted (@pxref{Mapped Devices}).
26363 @var{helper-packages} is a list of packages to be copied in the initrd. It may
26364 include @code{e2fsck/static} or other packages needed by the initrd to check
26365 the root file system.
26367 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26368 the desired console keyboard layout. This is done before @var{mapped-devices}
26369 are set up and before @var{file-systems} are mounted such that, should the
26370 user need to enter a passphrase or use the REPL, this happens using the
26371 intended keyboard layout.
26373 When @var{qemu-networking?} is true, set up networking with the standard QEMU
26374 parameters. When @var{virtio?} is true, load additional modules so that the
26375 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
26377 When @var{volatile-root?} is true, the root file system is writable but any changes
26381 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
26382 [#:mapped-devices '()] [#:keyboard-layout #f] @
26383 [#:qemu-networking? #f] [#:volatile-root? #f] @
26384 [#:linux-modules '()]
26385 Return as a file-like object a generic initrd, with kernel
26386 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
26387 mounted by the initrd, possibly in addition to the root file system specified
26388 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
26389 mappings to realize before @var{file-systems} are mounted.
26391 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26392 the desired console keyboard layout. This is done before @var{mapped-devices}
26393 are set up and before @var{file-systems} are mounted such that, should the
26394 user need to enter a passphrase or use the REPL, this happens using the
26395 intended keyboard layout.
26397 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
26399 The initrd is automatically populated with all the kernel modules necessary
26400 for @var{file-systems} and for the given options. Additional kernel
26401 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
26402 loaded at boot time in the order in which they appear.
26405 Needless to say, the initrds we produce and use embed a
26406 statically-linked Guile, and the initialization program is a Guile
26407 program. That gives a lot of flexibility. The
26408 @code{expression->initrd} procedure builds such an initrd, given the
26409 program to run in that initrd.
26411 @deffn {Scheme Procedure} expression->initrd @var{exp} @
26412 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
26413 Return as a file-like object a Linux initrd (a gzipped cpio archive)
26414 containing @var{guile} and that evaluates @var{exp}, a G-expression,
26415 upon booting. All the derivations referenced by @var{exp} are
26416 automatically copied to the initrd.
26419 @node Bootloader Configuration
26420 @section Bootloader Configuration
26423 @cindex boot loader
26425 The operating system supports multiple bootloaders. The bootloader is
26426 configured using @code{bootloader-configuration} declaration. All the
26427 fields of this structure are bootloader agnostic except for one field,
26428 @code{bootloader} that indicates the bootloader to be configured and
26431 Some of the bootloaders do not honor every field of
26432 @code{bootloader-configuration}. For instance, the extlinux
26433 bootloader does not support themes and thus ignores the @code{theme}
26436 @deftp {Data Type} bootloader-configuration
26437 The type of a bootloader configuration declaration.
26441 @item @code{bootloader}
26442 @cindex EFI, bootloader
26443 @cindex UEFI, bootloader
26444 @cindex BIOS, bootloader
26445 The bootloader to use, as a @code{bootloader} object. For now
26446 @code{grub-bootloader}, @code{grub-efi-bootloader},
26447 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
26449 @vindex grub-efi-bootloader
26450 @code{grub-efi-bootloader} allows to boot on modern systems using the
26451 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
26452 use if the installation image contains a @file{/sys/firmware/efi} directory
26453 when you boot it on your system.
26455 @vindex grub-bootloader
26456 @code{grub-bootloader} allows you to boot in particular Intel-based machines
26457 in ``legacy'' BIOS mode.
26459 @cindex ARM, bootloaders
26460 @cindex AArch64, bootloaders
26461 Available bootloaders are described in @code{(gnu bootloader @dots{})}
26462 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
26463 of bootloaders for a wide range of ARM and AArch64 systems, using the
26464 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
26466 @item @code{target}
26467 This is a string denoting the target onto which to install the
26470 The interpretation depends on the bootloader in question. For
26471 @code{grub-bootloader}, for example, it should be a device name understood by
26472 the bootloader @command{installer} command, such as @code{/dev/sda} or
26473 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
26474 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
26475 system, usually @file{/boot/efi}.
26477 @item @code{menu-entries} (default: @code{()})
26478 A possibly empty list of @code{menu-entry} objects (see below), denoting
26479 entries to appear in the bootloader menu, in addition to the current
26480 system entry and the entry pointing to previous system generations.
26482 @item @code{default-entry} (default: @code{0})
26483 The index of the default boot menu entry. Index 0 is for the entry of the
26486 @item @code{timeout} (default: @code{5})
26487 The number of seconds to wait for keyboard input before booting. Set to
26488 0 to boot immediately, and to -1 to wait indefinitely.
26490 @cindex keyboard layout, for the bootloader
26491 @item @code{keyboard-layout} (default: @code{#f})
26492 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
26493 layout, usually US@tie{}English (``qwerty'').
26495 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
26499 This option is currently ignored by bootloaders other than @code{grub} and
26503 @item @code{theme} (default: @var{#f})
26504 The bootloader theme object describing the theme to use. If no theme
26505 is provided, some bootloaders might use a default theme, that's true
26508 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
26509 The output terminals used for the bootloader boot menu, as a list of
26510 symbols. GRUB accepts the values: @code{console}, @code{serial},
26511 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
26512 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
26513 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
26514 configuration,,, grub,GNU GRUB manual}).
26516 @item @code{terminal-inputs} (default: @code{'()})
26517 The input terminals used for the bootloader boot menu, as a list of
26518 symbols. For GRUB, the default is the native platform terminal as
26519 determined at run-time. GRUB accepts the values: @code{console},
26520 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
26521 @code{usb_keyboard}. This field corresponds to the GRUB variable
26522 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
26525 @item @code{serial-unit} (default: @code{#f})
26526 The serial unit used by the bootloader, as an integer from 0 to 3.
26527 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
26528 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26530 @item @code{serial-speed} (default: @code{#f})
26531 The speed of the serial interface, as an integer. For GRUB, the
26532 default value is chosen at run-time; currently GRUB chooses
26533 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26540 Should you want to list additional boot menu entries @i{via} the
26541 @code{menu-entries} field above, you will need to create them with the
26542 @code{menu-entry} form. For example, imagine you want to be able to
26543 boot another distro (hard to imagine!), you can define a menu entry
26548 (label "The Other Distro")
26549 (linux "/boot/old/vmlinux-2.6.32")
26550 (linux-arguments '("root=/dev/sda2"))
26551 (initrd "/boot/old/initrd"))
26556 @deftp {Data Type} menu-entry
26557 The type of an entry in the bootloader menu.
26562 The label to show in the menu---e.g., @code{"GNU"}.
26565 The Linux kernel image to boot, for example:
26568 (file-append linux-libre "/bzImage")
26571 For GRUB, it is also possible to specify a device explicitly in the
26572 file path using GRUB's device naming convention (@pxref{Naming
26573 convention,,, grub, GNU GRUB manual}), for example:
26576 "(hd0,msdos1)/boot/vmlinuz"
26579 If the device is specified explicitly as above, then the @code{device}
26580 field is ignored entirely.
26582 @item @code{linux-arguments} (default: @code{()})
26583 The list of extra Linux kernel command-line arguments---e.g.,
26584 @code{("console=ttyS0")}.
26586 @item @code{initrd}
26587 A G-Expression or string denoting the file name of the initial RAM disk
26588 to use (@pxref{G-Expressions}).
26589 @item @code{device} (default: @code{#f})
26590 The device where the kernel and initrd are to be found---i.e., for GRUB,
26591 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
26593 This may be a file system label (a string), a file system UUID (a
26594 bytevector, @pxref{File Systems}), or @code{#f}, in which case
26595 the bootloader will search the device containing the file specified by
26596 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
26597 must @emph{not} be an OS device name such as @file{/dev/sda1}.
26605 @c FIXME: Write documentation once it's stable.
26606 For now only GRUB has theme support. GRUB themes are created using
26607 the @code{grub-theme} form, which is not fully documented yet.
26609 @deftp {Data Type} grub-theme
26610 Data type representing the configuration of the GRUB theme.
26613 @item @code{gfxmode} (default: @code{'("auto")})
26614 The GRUB @code{gfxmode} to set (a list of screen resolution strings, see
26615 @pxref{gfxmode,,, grub, GNU GRUB manual}).
26619 @defvr {Scheme Variable} %default-theme
26620 This is the default GRUB theme used by the operating system if no
26621 @code{theme} field is specified in @code{bootloader-configuration}
26624 It comes with a fancy background image displaying the GNU and Guix
26628 For example, to override the default resolution, you may use something
26633 (bootloader-configuration
26636 (inherit %default-theme)
26637 (gfxmode '("1024x786x32" "auto"))))))
26640 @node Invoking guix system
26641 @section Invoking @code{guix system}
26643 Once you have written an operating system declaration as seen in the
26644 previous section, it can be @dfn{instantiated} using the @command{guix
26645 system} command. The synopsis is:
26648 guix system @var{options}@dots{} @var{action} @var{file}
26651 @var{file} must be the name of a file containing an
26652 @code{operating-system} declaration. @var{action} specifies how the
26653 operating system is instantiated. Currently the following values are
26658 Display available service type definitions that match the given regular
26659 expressions, sorted by relevance:
26665 $ guix system search console
26666 name: console-fonts
26667 location: gnu/services/base.scm:806:2
26668 extends: shepherd-root
26669 description: Install the given fonts on the specified ttys (fonts are per
26670 + virtual console on GNU/Linux). The value of this service is a list of
26671 + tty/font pairs. The font can be the name of a font provided by the `kbd'
26672 + package or any valid argument to `setfont', as in this example:
26674 + '(("tty1" . "LatGrkCyr-8x16")
26675 + ("tty2" . (file-append
26677 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
26678 + ("tty3" . (file-append
26680 + "/share/consolefonts/ter-132n"))) ; for HDPI
26684 location: gnu/services/base.scm:1190:2
26685 extends: shepherd-root
26686 description: Provide console login using the `mingetty' program.
26690 location: gnu/services/base.scm:860:2
26692 description: Provide a console log-in service as specified by its
26693 + configuration value, a `login-configuration' object.
26699 As for @command{guix package --search}, the result is written in
26700 @code{recutils} format, which makes it easy to filter the output
26701 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
26704 Build the operating system described in @var{file}, activate it, and
26705 switch to it@footnote{This action (and the related actions
26706 @code{switch-generation} and @code{roll-back}) are usable only on
26707 systems already running Guix System.}.
26710 @c The paragraph below refers to the problem discussed at
26711 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
26712 It is highly recommended to run @command{guix pull} once before you run
26713 @command{guix system reconfigure} for the first time (@pxref{Invoking
26714 guix pull}). Failing to do that you would see an older version of Guix
26715 once @command{reconfigure} has completed.
26718 This effects all the configuration specified in @var{file}: user
26719 accounts, system services, global package list, setuid programs, etc.
26720 The command starts system services specified in @var{file} that are not
26721 currently running; if a service is currently running this command will
26722 arrange for it to be upgraded the next time it is stopped (e.g.@: by
26723 @code{herd stop X} or @code{herd restart X}).
26725 This command creates a new generation whose number is one greater than
26726 the current generation (as reported by @command{guix system
26727 list-generations}). If that generation already exists, it will be
26728 overwritten. This behavior mirrors that of @command{guix package}
26729 (@pxref{Invoking guix package}).
26731 It also adds a bootloader menu entry for the new OS configuration,
26732 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
26733 entries for older configurations to a submenu, allowing you to choose
26734 an older system generation at boot time should you need it.
26736 @cindex provenance tracking, of the operating system
26737 Upon completion, the new system is deployed under
26738 @file{/run/current-system}. This directory contains @dfn{provenance
26739 meta-data}: the list of channels in use (@pxref{Channels}) and
26740 @var{file} itself, when available. This information is useful should
26741 you later want to inspect how this particular generation was built.
26743 In fact, assuming @var{file} is self-contained, you can later rebuild
26744 generation @var{n} of your operating system with:
26747 guix time-machine \
26748 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
26749 system reconfigure \
26750 /var/guix/profiles/system-@var{n}-link/configuration.scm
26753 You can think of it as some sort of built-in version control! Your
26754 system is not just a binary artifact: @emph{it carries its own source}.
26755 @xref{Service Reference, @code{provenance-service-type}}, for more
26756 information on provenance tracking.
26758 @item switch-generation
26759 @cindex generations
26760 Switch to an existing system generation. This action atomically
26761 switches the system profile to the specified system generation. It
26762 also rearranges the system's existing bootloader menu entries. It
26763 makes the menu entry for the specified system generation the default,
26764 and it moves the entries for the other generations to a submenu, if
26765 supported by the bootloader being used. The next time the system
26766 boots, it will use the specified system generation.
26768 The bootloader itself is not being reinstalled when using this
26769 command. Thus, the installed bootloader is used with an updated
26770 configuration file.
26772 The target generation can be specified explicitly by its generation
26773 number. For example, the following invocation would switch to system
26777 guix system switch-generation 7
26780 The target generation can also be specified relative to the current
26781 generation with the form @code{+N} or @code{-N}, where @code{+3} means
26782 ``3 generations ahead of the current generation,'' and @code{-1} means
26783 ``1 generation prior to the current generation.'' When specifying a
26784 negative value such as @code{-1}, you must precede it with @code{--} to
26785 prevent it from being parsed as an option. For example:
26788 guix system switch-generation -- -1
26791 Currently, the effect of invoking this action is @emph{only} to switch
26792 the system profile to an existing generation and rearrange the
26793 bootloader menu entries. To actually start using the target system
26794 generation, you must reboot after running this action. In the future,
26795 it will be updated to do the same things as @command{reconfigure},
26796 like activating and deactivating services.
26798 This action will fail if the specified generation does not exist.
26801 @cindex rolling back
26802 Switch to the preceding system generation. The next time the system
26803 boots, it will use the preceding system generation. This is the inverse
26804 of @command{reconfigure}, and it is exactly the same as invoking
26805 @command{switch-generation} with an argument of @code{-1}.
26807 Currently, as with @command{switch-generation}, you must reboot after
26808 running this action to actually start using the preceding system
26811 @item delete-generations
26812 @cindex deleting system generations
26813 @cindex saving space
26814 Delete system generations, making them candidates for garbage collection
26815 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
26818 This works in the same way as @command{guix package --delete-generations}
26819 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
26820 arguments, all system generations but the current one are deleted:
26823 guix system delete-generations
26826 You can also select the generations you want to delete. The example below
26827 deletes all the system generations that are more than two month old:
26830 guix system delete-generations 2m
26833 Running this command automatically reinstalls the bootloader with an updated
26834 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
26835 longer lists the generations that have been deleted.
26838 Build the derivation of the operating system, which includes all the
26839 configuration files and programs needed to boot and run the system.
26840 This action does not actually install anything.
26843 Populate the given directory with all the files necessary to run the
26844 operating system specified in @var{file}. This is useful for first-time
26845 installations of Guix System. For instance:
26848 guix system init my-os-config.scm /mnt
26851 copies to @file{/mnt} all the store items required by the configuration
26852 specified in @file{my-os-config.scm}. This includes configuration
26853 files, packages, and so on. It also creates other essential files
26854 needed for the system to operate correctly---e.g., the @file{/etc},
26855 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
26857 This command also installs bootloader on the target specified in
26858 @file{my-os-config}, unless the @option{--no-bootloader} option was
26862 @cindex virtual machine
26864 @anchor{guix system vm}
26865 Build a virtual machine that contains the operating system declared in
26866 @var{file}, and return a script to run that virtual machine (VM).
26869 The @code{vm} action and others below
26870 can use KVM support in the Linux-libre kernel. Specifically, if the
26871 machine has hardware virtualization support, the corresponding
26872 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
26873 must exist and be readable and writable by the user and by the
26874 build users of the daemon (@pxref{Build Environment Setup}).
26877 Arguments given to the script are passed to QEMU as in the example
26878 below, which enables networking and requests 1@tie{}GiB of RAM for the
26882 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
26885 The VM shares its store with the host system.
26887 Additional file systems can be shared between the host and the VM using
26888 the @code{--share} and @code{--expose} command-line options: the former
26889 specifies a directory to be shared with write access, while the latter
26890 provides read-only access to the shared directory.
26892 The example below creates a VM in which the user's home directory is
26893 accessible read-only, and where the @file{/exchange} directory is a
26894 read-write mapping of @file{$HOME/tmp} on the host:
26897 guix system vm my-config.scm \
26898 --expose=$HOME --share=$HOME/tmp=/exchange
26901 On GNU/Linux, the default is to boot directly to the kernel; this has
26902 the advantage of requiring only a very tiny root disk image since the
26903 store of the host can then be mounted.
26905 The @code{--full-boot} option forces a complete boot sequence, starting
26906 with the bootloader. This requires more disk space since a root image
26907 containing at least the kernel, initrd, and bootloader data files must
26908 be created. The @code{--image-size} option can be used to specify the
26911 @cindex System images, creation in various formats
26912 @cindex Creating system images in various formats
26915 @itemx docker-image
26916 Return a virtual machine, disk image, or Docker image of the operating
26917 system declared in @var{file} that stands alone. By default,
26918 @command{guix system} estimates the size of the image needed to store
26919 the system, but you can use the @option{--image-size} option to specify
26920 a value. Docker images are built to contain exactly what they need, so
26921 the @option{--image-size} option is ignored in the case of
26922 @code{docker-image}.
26924 You can specify the root file system type by using the
26925 @option{--file-system-type} option. It defaults to @code{ext4}.
26927 When using @code{vm-image}, the returned image is in qcow2 format, which
26928 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
26929 for more information on how to run the image in a virtual machine.
26931 When using @code{disk-image}, a raw disk image is produced; it can be
26932 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
26933 the device corresponding to a USB stick, one can copy the image to it
26934 using the following command:
26937 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
26940 When using @code{docker-image}, a Docker image is produced. Guix builds
26941 the image from scratch, not from a pre-existing Docker base image. As a
26942 result, it contains @emph{exactly} what you define in the operating
26943 system configuration file. You can then load the image and launch a
26944 Docker container using commands like the following:
26947 image_id="`docker load < guix-system-docker-image.tar.gz`"
26948 container_id="`docker create $image_id`"
26949 docker start $container_id
26952 This command starts a new Docker container from the specified image. It
26953 will boot the Guix system in the usual manner, which means it will
26954 start any services you have defined in the operating system
26955 configuration. You can get an interactive shell running in the container
26956 using @command{docker exec}:
26959 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
26962 Depending on what you run in the Docker container, it
26963 may be necessary to give the container additional permissions. For
26964 example, if you intend to build software using Guix inside of the Docker
26965 container, you may need to pass the @option{--privileged} option to
26966 @code{docker create}.
26969 Return a script to run the operating system declared in @var{file}
26970 within a container. Containers are a set of lightweight isolation
26971 mechanisms provided by the kernel Linux-libre. Containers are
26972 substantially less resource-demanding than full virtual machines since
26973 the kernel, shared objects, and other resources can be shared with the
26974 host system; this also means they provide thinner isolation.
26976 Currently, the script must be run as root in order to support more than
26977 a single user and group. The container shares its store with the host
26980 As with the @code{vm} action (@pxref{guix system vm}), additional file
26981 systems to be shared between the host and container can be specified
26982 using the @option{--share} and @option{--expose} options:
26985 guix system container my-config.scm \
26986 --expose=$HOME --share=$HOME/tmp=/exchange
26990 This option requires Linux-libre 3.19 or newer.
26995 @var{options} can contain any of the common build options (@pxref{Common
26996 Build Options}). In addition, @var{options} can contain one of the
27000 @item --expression=@var{expr}
27001 @itemx -e @var{expr}
27002 Consider the operating-system @var{expr} evaluates to.
27003 This is an alternative to specifying a file which evaluates to an
27005 This is used to generate the Guix system installer @pxref{Building the
27006 Installation Image}).
27008 @item --system=@var{system}
27009 @itemx -s @var{system}
27010 Attempt to build for @var{system} instead of the host system type.
27011 This works as per @command{guix build} (@pxref{Invoking guix build}).
27015 Return the derivation file name of the given operating system without
27018 @cindex provenance tracking, of the operating system
27019 @item --save-provenance
27020 As discussed above, @command{guix system init} and @command{guix system
27021 reconfigure} always save provenance information @i{via} a dedicated
27022 service (@pxref{Service Reference, @code{provenance-service-type}}).
27023 However, other commands don't do that by default. If you wish to, say,
27024 create a virtual machine image that contains provenance information, you
27028 guix system vm-image --save-provenance config.scm
27031 That way, the resulting image will effectively ``embed its own source''
27032 in the form of meta-data in @file{/run/current-system}. With that
27033 information, one can rebuild the image to make sure it really contains
27034 what it pretends to contain; or they could use that to derive a variant
27037 @item --file-system-type=@var{type}
27038 @itemx -t @var{type}
27039 For the @code{disk-image} action, create a file system of the given
27040 @var{type} on the image.
27042 When this option is omitted, @command{guix system} uses @code{ext4}.
27044 @cindex ISO-9660 format
27045 @cindex CD image format
27046 @cindex DVD image format
27047 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
27048 for burning on CDs and DVDs.
27050 @item --image-size=@var{size}
27051 For the @code{vm-image} and @code{disk-image} actions, create an image
27052 of the given @var{size}. @var{size} may be a number of bytes, or it may
27053 include a unit as a suffix (@pxref{Block size, size specifications,,
27054 coreutils, GNU Coreutils}).
27056 When this option is omitted, @command{guix system} computes an estimate
27057 of the image size as a function of the size of the system declared in
27062 For the @code{container} action, allow containers to access the host network,
27063 that is, do not create a network namespace.
27065 @item --root=@var{file}
27066 @itemx -r @var{file}
27067 Make @var{file} a symlink to the result, and register it as a garbage
27070 @item --skip-checks
27071 Skip pre-installation safety checks.
27073 By default, @command{guix system init} and @command{guix system
27074 reconfigure} perform safety checks: they make sure the file systems that
27075 appear in the @code{operating-system} declaration actually exist
27076 (@pxref{File Systems}), and that any Linux kernel modules that may be
27077 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
27078 RAM Disk}). Passing this option skips these tests altogether.
27081 @cindex on-error strategy
27082 @cindex error strategy
27083 @item --on-error=@var{strategy}
27084 Apply @var{strategy} when an error occurs when reading @var{file}.
27085 @var{strategy} may be one of the following:
27088 @item nothing-special
27089 Report the error concisely and exit. This is the default strategy.
27092 Likewise, but also display a backtrace.
27095 Report the error and enter Guile's debugger. From there, you can run
27096 commands such as @code{,bt} to get a backtrace, @code{,locals} to
27097 display local variable values, and more generally inspect the state of the
27098 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
27099 a list of available debugging commands.
27103 Once you have built, configured, re-configured, and re-re-configured
27104 your Guix installation, you may find it useful to list the operating
27105 system generations available on disk---and that you can choose from the
27106 bootloader boot menu:
27111 Describe the current system generation: its file name, the kernel and
27112 bootloader used, etc., as well as provenance information when available.
27114 @item list-generations
27115 List a summary of each generation of the operating system available on
27116 disk, in a human-readable way. This is similar to the
27117 @option{--list-generations} option of @command{guix package}
27118 (@pxref{Invoking guix package}).
27120 Optionally, one can specify a pattern, with the same syntax that is used
27121 in @command{guix package --list-generations}, to restrict the list of
27122 generations displayed. For instance, the following command displays
27123 generations that are up to 10 days old:
27126 $ guix system list-generations 10d
27131 The @command{guix system} command has even more to offer! The following
27132 sub-commands allow you to visualize how your system services relate to
27135 @anchor{system-extension-graph}
27138 @item extension-graph
27139 Emit in Dot/Graphviz format to standard output the @dfn{service
27140 extension graph} of the operating system defined in @var{file}
27141 (@pxref{Service Composition}, for more information on service
27147 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
27150 produces a PDF file showing the extension relations among services.
27152 @anchor{system-shepherd-graph}
27153 @item shepherd-graph
27154 Emit in Dot/Graphviz format to standard output the @dfn{dependency
27155 graph} of shepherd services of the operating system defined in
27156 @var{file}. @xref{Shepherd Services}, for more information and for an
27161 @node Invoking guix deploy
27162 @section Invoking @code{guix deploy}
27164 We've already seen @code{operating-system} declarations used to manage a
27165 machine's configuration locally. Suppose you need to configure multiple
27166 machines, though---perhaps you're managing a service on the web that's
27167 comprised of several servers. @command{guix deploy} enables you to use those
27168 same @code{operating-system} declarations to manage multiple remote hosts at
27169 once as a logical ``deployment''.
27172 The functionality described in this section is still under development
27173 and is subject to change. Get in touch with us on
27174 @email{guix-devel@@gnu.org}!
27178 guix deploy @var{file}
27181 Such an invocation will deploy the machines that the code within @var{file}
27182 evaluates to. As an example, @var{file} might contain a definition like this:
27185 ;; This is a Guix deployment of a "bare bones" setup, with
27186 ;; no X11 display server, to a machine with an SSH daemon
27187 ;; listening on localhost:2222. A configuration such as this
27188 ;; may be appropriate for virtual machine with ports
27189 ;; forwarded to the host's loopback interface.
27191 (use-service-modules networking ssh)
27192 (use-package-modules bootloaders)
27196 (host-name "gnu-deployed")
27197 (timezone "Etc/UTC")
27198 (bootloader (bootloader-configuration
27199 (bootloader grub-bootloader)
27200 (target "/dev/vda")
27201 (terminal-outputs '(console))))
27202 (file-systems (cons (file-system
27204 (device "/dev/vda1")
27206 %base-file-systems))
27208 (append (list (service dhcp-client-service-type)
27209 (service openssh-service-type
27210 (openssh-configuration
27211 (permit-root-login #t)
27212 (allow-empty-passwords? #t))))
27216 (operating-system %system)
27217 (environment managed-host-environment-type)
27218 (configuration (machine-ssh-configuration
27219 (host-name "localhost")
27220 (system "x86_64-linux")
27222 (identity "./id_rsa")
27226 The file should evaluate to a list of @var{machine} objects. This example,
27227 upon being deployed, will create a new generation on the remote system
27228 realizing the @code{operating-system} declaration @code{%system}.
27229 @code{environment} and @code{configuration} specify how the machine should be
27230 provisioned---that is, how the computing resources should be created and
27231 managed. The above example does not create any resources, as a
27232 @code{'managed-host} is a machine that is already running the Guix system and
27233 available over the network. This is a particularly simple case; a more
27234 complex deployment may involve, for example, starting virtual machines through
27235 a Virtual Private Server (VPS) provider. In such a case, a different
27236 @var{environment} type would be used.
27238 Do note that you first need to generate a key pair on the coordinator machine
27239 to allow the daemon to export signed archives of files from the store
27240 (@pxref{Invoking guix archive}).
27243 # guix archive --generate-key
27247 Each target machine must authorize the key of the master machine so that it
27248 accepts store items it receives from the coordinator:
27251 # guix archive --authorize < coordinator-public-key.txt
27254 @code{user}, in this example, specifies the name of the user account to log in
27255 as to perform the deployment. Its default value is @code{root}, but root
27256 login over SSH may be forbidden in some cases. To work around this,
27257 @command{guix deploy} can log in as an unprivileged user and employ
27258 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
27259 currently installed on the remote and can be invoked non-interactively as
27260 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
27261 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
27262 be accomplished with the following operating system configuration snippet:
27266 (gnu system)) ;for %sudoers-specification
27268 (define %user "username")
27273 (plain-file "sudoers"
27274 (string-append (plain-file-content %sudoers-specification)
27275 (format #f "~a ALL = NOPASSWD: ALL~%"
27280 For more information regarding the format of the @file{sudoers} file,
27281 consult @command{man sudoers}.
27283 @deftp {Data Type} machine
27284 This is the data type representing a single machine in a heterogeneous Guix
27288 @item @code{operating-system}
27289 The object of the operating system configuration to deploy.
27291 @item @code{environment}
27292 An @code{environment-type} describing how the machine should be provisioned.
27294 @item @code{configuration} (default: @code{#f})
27295 An object describing the configuration for the machine's @code{environment}.
27296 If the @code{environment} has a default configuration, @code{#f} may be used.
27297 If @code{#f} is used for an environment with no default configuration,
27298 however, an error will be thrown.
27302 @deftp {Data Type} machine-ssh-configuration
27303 This is the data type representing the SSH client parameters for a machine
27304 with an @code{environment} of @code{managed-host-environment-type}.
27307 @item @code{host-name}
27308 @item @code{build-locally?} (default: @code{#t})
27309 If false, system derivations will be built on the machine being deployed to.
27310 @item @code{system}
27311 The system type describing the architecture of the machine being deployed
27312 to---e.g., @code{"x86_64-linux"}.
27313 @item @code{authorize?} (default: @code{#t})
27314 If true, the coordinator's signing key will be added to the remote's ACL
27316 @item @code{port} (default: @code{22})
27317 @item @code{user} (default: @code{"root"})
27318 @item @code{identity} (default: @code{#f})
27319 If specified, the path to the SSH private key to use to authenticate with the
27322 @item @code{host-key} (default: @code{#f})
27323 This should be the SSH host key of the machine, which looks like this:
27326 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
27329 When @code{host-key} is @code{#f}, the server is authenticated against
27330 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
27336 @deftp {Data Type} digital-ocean-configuration
27337 This is the data type describing the Droplet that should be created for a
27338 machine with an @code{environment} of @code{digital-ocean-environment-type}.
27341 @item @code{ssh-key}
27342 The path to the SSH private key to use to authenticate with the remote
27343 host. In the future, this field may not exist.
27345 A list of string ``tags'' that uniquely identify the machine. Must be given
27346 such that no two machines in the deployment have the same set of tags.
27347 @item @code{region}
27348 A Digital Ocean region slug, such as @code{"nyc3"}.
27350 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
27351 @item @code{enable-ipv6?}
27352 Whether or not the droplet should be created with IPv6 networking.
27356 @node Running Guix in a VM
27357 @section Running Guix in a Virtual Machine
27359 @cindex virtual machine
27360 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
27362 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
27363 This image is a compressed image in QCOW format. You will first need to
27364 decompress with @command{xz -d}, and then you can pass it to an emulator such
27365 as QEMU (see below for details).
27367 This image boots the Xfce graphical environment and it contains some
27368 commonly-used tools. You can install more software in the image by running
27369 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
27370 also reconfigure the system based on its initial configuration file available
27371 as @file{/run/current-system/configuration.scm} (@pxref{Using the
27372 Configuration System}).
27374 Instead of using this pre-built image, one can also build their own virtual
27375 machine image using @command{guix system vm-image} (@pxref{Invoking guix
27376 system}). The returned image is in qcow2 format, which the
27377 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
27380 If you built your own image, you must copy it out of the store
27381 (@pxref{The Store}) and give yourself permission to write to the copy
27382 before you can use it. When invoking QEMU, you must choose a system
27383 emulator that is suitable for your hardware platform. Here is a minimal
27384 QEMU invocation that will boot the result of @command{guix system
27385 vm-image} on x86_64 hardware:
27388 $ qemu-system-x86_64 \
27389 -nic user,model=virtio-net-pci \
27390 -enable-kvm -m 1024 \
27391 -device virtio-blk,drive=myhd \
27392 -drive if=none,file=/tmp/qemu-image,id=myhd
27395 Here is what each of these options means:
27398 @item qemu-system-x86_64
27399 This specifies the hardware platform to emulate. This should match the
27402 @item -nic user,model=virtio-net-pci
27403 Enable the unprivileged user-mode network stack. The guest OS can
27404 access the host but not vice versa. This is the simplest way to get the
27405 guest OS online. @code{model} specifies which network device to emulate:
27406 @code{virtio-net-pci} is a special device made for virtualized operating
27407 systems and recommended for most uses. Assuming your hardware platform is
27408 x86_64, you can get a list of available NIC models by running
27409 @command{qemu-system-x86_64 -nic model=help}.
27412 If your system has hardware virtualization extensions, enabling the
27413 virtual machine support (KVM) of the Linux kernel will make things run
27416 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
27418 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
27419 which may be insufficient for some operations.
27421 @item -device virtio-blk,drive=myhd
27422 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
27423 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
27424 better performance than if it were emulating a complete disk drive. See the
27425 QEMU and KVM documentation for more info.
27427 @item -drive if=none,file=/tmp/qemu-image,id=myhd
27428 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
27429 the ``myhd'' drive.
27432 The default @command{run-vm.sh} script that is returned by an invocation of
27433 @command{guix system vm} does not add a @command{-nic user} flag by default.
27434 To get network access from within the vm add the @code{(dhcp-client-service)}
27435 to your system definition and start the VM using
27436 @command{`guix system vm config.scm` -nic user}. An important caveat of using
27437 @command{-nic user} for networking is that @command{ping} will not work, because
27438 it uses the ICMP protocol. You'll have to use a different command to check for
27439 network connectivity, for example @command{guix download}.
27441 @subsection Connecting Through SSH
27445 To enable SSH inside a VM you need to add an SSH server like
27446 @code{openssh-service-type} to your VM (@pxref{Networking Services,
27447 @code{openssh-service-type}}). In addition you need to forward the SSH port,
27448 22 by default, to the host. You can do this with
27451 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
27454 To connect to the VM you can run
27457 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
27460 The @command{-p} tells @command{ssh} the port you want to connect to.
27461 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
27462 every time you modify your @command{config.scm} file and the
27463 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
27464 connection to an unknown host every time you connect.
27466 @subsection Using @command{virt-viewer} with Spice
27468 As an alternative to the default @command{qemu} graphical client you can
27469 use the @command{remote-viewer} from the @command{virt-viewer} package. To
27470 connect pass the @command{-spice port=5930,disable-ticketing} flag to
27471 @command{qemu}. See previous section for further information on how to do this.
27473 Spice also allows you to do some nice stuff like share your clipboard with your
27474 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
27477 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
27478 -chardev spicevmc,name=vdagent,id=vdagent
27479 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
27480 name=com.redhat.spice.0
27483 You'll also need to add the @code{(spice-vdagent-service)} to your
27484 system definition (@pxref{Miscellaneous Services, Spice service}).
27486 @node Defining Services
27487 @section Defining Services
27489 The previous sections show the available services and how one can combine
27490 them in an @code{operating-system} declaration. But how do we define
27491 them in the first place? And what is a service anyway?
27494 * Service Composition:: The model for composing services.
27495 * Service Types and Services:: Types and services.
27496 * Service Reference:: API reference.
27497 * Shepherd Services:: A particular type of service.
27500 @node Service Composition
27501 @subsection Service Composition
27505 Here we define a @dfn{service} as, broadly, something that extends the
27506 functionality of the operating system. Often a service is a process---a
27507 @dfn{daemon}---started when the system boots: a secure shell server, a
27508 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
27509 whose execution can be triggered by another daemon---e.g., an FTP server
27510 started by @command{inetd} or a D-Bus service activated by
27511 @command{dbus-daemon}. Occasionally, a service does not map to a
27512 daemon. For instance, the ``account'' service collects user accounts
27513 and makes sure they exist when the system runs; the ``udev'' service
27514 collects device management rules and makes them available to the eudev
27515 daemon; the @file{/etc} service populates the @file{/etc} directory
27518 @cindex service extensions
27519 Guix system services are connected by @dfn{extensions}. For instance, the
27520 secure shell service @emph{extends} the Shepherd---the
27521 initialization system, running as PID@tie{}1---by giving it the command
27522 lines to start and stop the secure shell daemon (@pxref{Networking
27523 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
27524 service by passing it its @file{.service} specification, and extends the
27525 udev service by passing it device management rules (@pxref{Desktop
27526 Services, @code{upower-service}}); the Guix daemon service extends the
27527 Shepherd by passing it the command lines to start and stop the daemon,
27528 and extends the account service by passing it a list of required build
27529 user accounts (@pxref{Base Services}).
27531 All in all, services and their ``extends'' relations form a directed
27532 acyclic graph (DAG). If we represent services as boxes and extensions
27533 as arrows, a typical system might provide something like this:
27535 @image{images/service-graph,,5in,Typical service extension graph.}
27537 @cindex system service
27538 At the bottom, we see the @dfn{system service}, which produces the
27539 directory containing everything to run and boot the system, as returned
27540 by the @command{guix system build} command. @xref{Service Reference},
27541 to learn about the other service types shown here.
27542 @xref{system-extension-graph, the @command{guix system extension-graph}
27543 command}, for information on how to generate this representation for a
27544 particular operating system definition.
27546 @cindex service types
27547 Technically, developers can define @dfn{service types} to express these
27548 relations. There can be any number of services of a given type on the
27549 system---for instance, a system running two instances of the GNU secure
27550 shell server (lsh) has two instances of @code{lsh-service-type}, with
27551 different parameters.
27553 The following section describes the programming interface for service
27554 types and services.
27556 @node Service Types and Services
27557 @subsection Service Types and Services
27559 A @dfn{service type} is a node in the DAG described above. Let us start
27560 with a simple example, the service type for the Guix build daemon
27561 (@pxref{Invoking guix-daemon}):
27564 (define guix-service-type
27568 (list (service-extension shepherd-root-service-type guix-shepherd-service)
27569 (service-extension account-service-type guix-accounts)
27570 (service-extension activation-service-type guix-activation)))
27571 (default-value (guix-configuration))))
27575 It defines three things:
27579 A name, whose sole purpose is to make inspection and debugging easier.
27582 A list of @dfn{service extensions}, where each extension designates the
27583 target service type and a procedure that, given the parameters of the
27584 service, returns a list of objects to extend the service of that type.
27586 Every service type has at least one service extension. The only
27587 exception is the @dfn{boot service type}, which is the ultimate service.
27590 Optionally, a default value for instances of this type.
27593 In this example, @code{guix-service-type} extends three services:
27596 @item shepherd-root-service-type
27597 The @code{guix-shepherd-service} procedure defines how the Shepherd
27598 service is extended. Namely, it returns a @code{<shepherd-service>}
27599 object that defines how @command{guix-daemon} is started and stopped
27600 (@pxref{Shepherd Services}).
27602 @item account-service-type
27603 This extension for this service is computed by @code{guix-accounts},
27604 which returns a list of @code{user-group} and @code{user-account}
27605 objects representing the build user accounts (@pxref{Invoking
27608 @item activation-service-type
27609 Here @code{guix-activation} is a procedure that returns a gexp, which is
27610 a code snippet to run at ``activation time''---e.g., when the service is
27614 A service of this type is instantiated like this:
27617 (service guix-service-type
27618 (guix-configuration
27620 (use-substitutes? #f)))
27623 The second argument to the @code{service} form is a value representing
27624 the parameters of this specific service instance.
27625 @xref{guix-configuration-type, @code{guix-configuration}}, for
27626 information about the @code{guix-configuration} data type. When the
27627 value is omitted, the default value specified by
27628 @code{guix-service-type} is used:
27631 (service guix-service-type)
27634 @code{guix-service-type} is quite simple because it extends other
27635 services but is not extensible itself.
27637 @c @subsubsubsection Extensible Service Types
27639 The service type for an @emph{extensible} service looks like this:
27642 (define udev-service-type
27643 (service-type (name 'udev)
27645 (list (service-extension shepherd-root-service-type
27646 udev-shepherd-service)))
27648 (compose concatenate) ;concatenate the list of rules
27649 (extend (lambda (config rules)
27651 (($ <udev-configuration> udev initial-rules)
27652 (udev-configuration
27653 (udev udev) ;the udev package to use
27654 (rules (append initial-rules rules)))))))))
27657 This is the service type for the
27658 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
27659 management daemon}. Compared to the previous example, in addition to an
27660 extension of @code{shepherd-root-service-type}, we see two new fields:
27664 This is the procedure to @dfn{compose} the list of extensions to
27665 services of this type.
27667 Services can extend the udev service by passing it lists of rules; we
27668 compose those extensions simply by concatenating them.
27671 This procedure defines how the value of the service is @dfn{extended} with
27672 the composition of the extensions.
27674 Udev extensions are composed into a list of rules, but the udev service
27675 value is itself a @code{<udev-configuration>} record. So here, we
27676 extend that record by appending the list of rules it contains to the
27677 list of contributed rules.
27680 This is a string giving an overview of the service type. The string can
27681 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
27682 @command{guix system search} command searches these strings and displays
27683 them (@pxref{Invoking guix system}).
27686 There can be only one instance of an extensible service type such as
27687 @code{udev-service-type}. If there were more, the
27688 @code{service-extension} specifications would be ambiguous.
27690 Still here? The next section provides a reference of the programming
27691 interface for services.
27693 @node Service Reference
27694 @subsection Service Reference
27696 We have seen an overview of service types (@pxref{Service Types and
27697 Services}). This section provides a reference on how to manipulate
27698 services and service types. This interface is provided by the
27699 @code{(gnu services)} module.
27701 @deffn {Scheme Procedure} service @var{type} [@var{value}]
27702 Return a new service of @var{type}, a @code{<service-type>} object (see
27703 below.) @var{value} can be any object; it represents the parameters of
27704 this particular service instance.
27706 When @var{value} is omitted, the default value specified by @var{type}
27707 is used; if @var{type} does not specify a default value, an error is
27710 For instance, this:
27713 (service openssh-service-type)
27717 is equivalent to this:
27720 (service openssh-service-type
27721 (openssh-configuration))
27724 In both cases the result is an instance of @code{openssh-service-type}
27725 with the default configuration.
27728 @deffn {Scheme Procedure} service? @var{obj}
27729 Return true if @var{obj} is a service.
27732 @deffn {Scheme Procedure} service-kind @var{service}
27733 Return the type of @var{service}---i.e., a @code{<service-type>} object.
27736 @deffn {Scheme Procedure} service-value @var{service}
27737 Return the value associated with @var{service}. It represents its
27741 Here is an example of how a service is created and manipulated:
27745 (service nginx-service-type
27746 (nginx-configuration
27748 (log-directory log-directory)
27749 (run-directory run-directory)
27750 (file config-file))))
27755 (eq? (service-kind s) nginx-service-type)
27759 The @code{modify-services} form provides a handy way to change the
27760 parameters of some of the services of a list such as
27761 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
27762 evaluates to a list of services. Of course, you could always use
27763 standard list combinators such as @code{map} and @code{fold} to do that
27764 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
27765 @code{modify-services} simply provides a more concise form for this
27768 @deffn {Scheme Syntax} modify-services @var{services} @
27769 (@var{type} @var{variable} => @var{body}) @dots{}
27771 Modify the services listed in @var{services} according to the given
27772 clauses. Each clause has the form:
27775 (@var{type} @var{variable} => @var{body})
27778 where @var{type} is a service type---e.g.,
27779 @code{guix-service-type}---and @var{variable} is an identifier that is
27780 bound within the @var{body} to the service parameters---e.g., a
27781 @code{guix-configuration} instance---of the original service of that
27784 The @var{body} should evaluate to the new service parameters, which will
27785 be used to configure the new service. This new service will replace the
27786 original in the resulting list. Because a service's service parameters
27787 are created using @code{define-record-type*}, you can write a succinct
27788 @var{body} that evaluates to the new service parameters by using the
27789 @code{inherit} feature that @code{define-record-type*} provides.
27791 @xref{Using the Configuration System}, for example usage.
27795 Next comes the programming interface for service types. This is
27796 something you want to know when writing new service definitions, but not
27797 necessarily when simply looking for ways to customize your
27798 @code{operating-system} declaration.
27800 @deftp {Data Type} service-type
27801 @cindex service type
27802 This is the representation of a @dfn{service type} (@pxref{Service Types
27807 This is a symbol, used only to simplify inspection and debugging.
27809 @item @code{extensions}
27810 A non-empty list of @code{<service-extension>} objects (see below).
27812 @item @code{compose} (default: @code{#f})
27813 If this is @code{#f}, then the service type denotes services that cannot
27814 be extended---i.e., services that do not receive ``values'' from other
27817 Otherwise, it must be a one-argument procedure. The procedure is called
27818 by @code{fold-services} and is passed a list of values collected from
27819 extensions. It may return any single value.
27821 @item @code{extend} (default: @code{#f})
27822 If this is @code{#f}, services of this type cannot be extended.
27824 Otherwise, it must be a two-argument procedure: @code{fold-services}
27825 calls it, passing it the initial value of the service as the first
27826 argument and the result of applying @code{compose} to the extension
27827 values as the second argument. It must return a value that is a valid
27828 parameter value for the service instance.
27831 @xref{Service Types and Services}, for examples.
27834 @deffn {Scheme Procedure} service-extension @var{target-type} @
27836 Return a new extension for services of type @var{target-type}.
27837 @var{compute} must be a one-argument procedure: @code{fold-services}
27838 calls it, passing it the value associated with the service that provides
27839 the extension; it must return a valid value for the target service.
27842 @deffn {Scheme Procedure} service-extension? @var{obj}
27843 Return true if @var{obj} is a service extension.
27846 Occasionally, you might want to simply extend an existing service. This
27847 involves creating a new service type and specifying the extension of
27848 interest, which can be verbose; the @code{simple-service} procedure
27849 provides a shorthand for this.
27851 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
27852 Return a service that extends @var{target} with @var{value}. This works
27853 by creating a singleton service type @var{name}, of which the returned
27854 service is an instance.
27856 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
27860 (simple-service 'my-mcron-job mcron-service-type
27861 #~(job '(next-hour (3)) "guix gc -F 2G"))
27865 At the core of the service abstraction lies the @code{fold-services}
27866 procedure, which is responsible for ``compiling'' a list of services
27867 down to a single directory that contains everything needed to boot and
27868 run the system---the directory shown by the @command{guix system build}
27869 command (@pxref{Invoking guix system}). In essence, it propagates
27870 service extensions down the service graph, updating each node parameters
27871 on the way, until it reaches the root node.
27873 @deffn {Scheme Procedure} fold-services @var{services} @
27874 [#:target-type @var{system-service-type}]
27875 Fold @var{services} by propagating their extensions down to the root of
27876 type @var{target-type}; return the root service adjusted accordingly.
27879 Lastly, the @code{(gnu services)} module also defines several essential
27880 service types, some of which are listed below.
27882 @defvr {Scheme Variable} system-service-type
27883 This is the root of the service graph. It produces the system directory
27884 as returned by the @command{guix system build} command.
27887 @defvr {Scheme Variable} boot-service-type
27888 The type of the ``boot service'', which produces the @dfn{boot script}.
27889 The boot script is what the initial RAM disk runs when booting.
27892 @defvr {Scheme Variable} etc-service-type
27893 The type of the @file{/etc} service. This service is used to create
27894 files under @file{/etc} and can be extended by
27895 passing it name/file tuples such as:
27898 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
27901 In this example, the effect would be to add an @file{/etc/issue} file
27902 pointing to the given file.
27905 @defvr {Scheme Variable} setuid-program-service-type
27906 Type for the ``setuid-program service''. This service collects lists of
27907 executable file names, passed as gexps, and adds them to the set of
27908 setuid-root programs on the system (@pxref{Setuid Programs}).
27911 @defvr {Scheme Variable} profile-service-type
27912 Type of the service that populates the @dfn{system profile}---i.e., the
27913 programs under @file{/run/current-system/profile}. Other services can
27914 extend it by passing it lists of packages to add to the system profile.
27917 @cindex provenance tracking, of the operating system
27918 @defvr {Scheme Variable} provenance-service-type
27919 This is the type of the service that records @dfn{provenance meta-data}
27920 in the system itself. It creates several files under
27921 @file{/run/current-system}:
27925 This is a ``channel file'' that can be passed to @command{guix pull -C}
27926 or @command{guix time-machine -C}, and which describes the channels used
27927 to build the system, if that information was available
27928 (@pxref{Channels}).
27930 @item configuration.scm
27931 This is the file that was passed as the value for this
27932 @code{provenance-service-type} service. By default, @command{guix
27933 system reconfigure} automatically passes the OS configuration file it
27934 received on the command line.
27937 This contains the same information as the two other files but in a
27938 format that is more readily processable.
27941 In general, these two pieces of information (channels and configuration
27942 file) are enough to reproduce the operating system ``from source''.
27945 This information is necessary to rebuild your operating system, but it
27946 is not always sufficient. In particular, @file{configuration.scm}
27947 itself is insufficient if it is not self-contained---if it refers to
27948 external Guile modules or to extra files. If you want
27949 @file{configuration.scm} to be self-contained, we recommend that modules
27950 or files it refers to be part of a channel.
27952 Besides, provenance meta-data is ``silent'' in the sense that it does
27953 not change the bits contained in your system, @emph{except for the
27954 meta-data bits themselves}. Two different OS configurations or sets of
27955 channels can lead to the same system, bit-for-bit; when
27956 @code{provenance-service-type} is used, these two systems will have
27957 different meta-data and thus different store file names, which makes
27958 comparison less trivial.
27961 This service is automatically added to your operating system
27962 configuration when you use @command{guix system reconfigure},
27963 @command{guix system init}, or @command{guix deploy}.
27966 @node Shepherd Services
27967 @subsection Shepherd Services
27969 @cindex shepherd services
27971 @cindex init system
27972 The @code{(gnu services shepherd)} module provides a way to define
27973 services managed by the GNU@tie{}Shepherd, which is the
27974 initialization system---the first process that is started when the
27975 system boots, also known as PID@tie{}1
27976 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
27978 Services in the Shepherd can depend on each other. For instance, the
27979 SSH daemon may need to be started after the syslog daemon has been
27980 started, which in turn can only happen once all the file systems have
27981 been mounted. The simple operating system defined earlier (@pxref{Using
27982 the Configuration System}) results in a service graph like this:
27984 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
27986 You can actually generate such a graph for any operating system
27987 definition using the @command{guix system shepherd-graph} command
27988 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
27990 The @code{%shepherd-root-service} is a service object representing
27991 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
27992 by passing it lists of @code{<shepherd-service>} objects.
27994 @deftp {Data Type} shepherd-service
27995 The data type representing a service managed by the Shepherd.
27998 @item @code{provision}
27999 This is a list of symbols denoting what the service provides.
28001 These are the names that may be passed to @command{herd start},
28002 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
28003 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
28004 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
28006 @item @code{requirement} (default: @code{'()})
28007 List of symbols denoting the Shepherd services this one depends on.
28009 @cindex one-shot services, for the Shepherd
28010 @item @code{one-shot?} (default: @code{#f})
28011 Whether this service is @dfn{one-shot}. One-shot services stop immediately
28012 after their @code{start} action has completed. @xref{Slots of services,,,
28013 shepherd, The GNU Shepherd Manual}, for more info.
28015 @item @code{respawn?} (default: @code{#t})
28016 Whether to restart the service when it stops, for instance when the
28017 underlying process dies.
28020 @itemx @code{stop} (default: @code{#~(const #f)})
28021 The @code{start} and @code{stop} fields refer to the Shepherd's
28022 facilities to start and stop processes (@pxref{Service De- and
28023 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
28024 G-expressions that get expanded in the Shepherd configuration file
28025 (@pxref{G-Expressions}).
28027 @item @code{actions} (default: @code{'()})
28028 @cindex actions, of Shepherd services
28029 This is a list of @code{shepherd-action} objects (see below) defining
28030 @dfn{actions} supported by the service, in addition to the standard
28031 @code{start} and @code{stop} actions. Actions listed here become available as
28032 @command{herd} sub-commands:
28035 herd @var{action} @var{service} [@var{arguments}@dots{}]
28038 @item @code{auto-start?} (default: @code{#t})
28039 Whether this service should be started automatically by the Shepherd. If it
28040 is @code{#f} the service has to be started manually with @code{herd start}.
28042 @item @code{documentation}
28043 A documentation string, as shown when running:
28046 herd doc @var{service-name}
28049 where @var{service-name} is one of the symbols in @code{provision}
28050 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
28052 @item @code{modules} (default: @code{%default-modules})
28053 This is the list of modules that must be in scope when @code{start} and
28054 @code{stop} are evaluated.
28059 @deftp {Data Type} shepherd-action
28060 This is the data type that defines additional actions implemented by a
28061 Shepherd service (see above).
28065 Symbol naming the action.
28067 @item documentation
28068 This is a documentation string for the action. It can be viewed by running:
28071 herd doc @var{service} action @var{action}
28075 This should be a gexp that evaluates to a procedure of at least one argument,
28076 which is the ``running value'' of the service (@pxref{Slots of services,,,
28077 shepherd, The GNU Shepherd Manual}).
28080 The following example defines an action called @code{say-hello} that kindly
28086 (documentation "Say hi!")
28087 (procedure #~(lambda (running . args)
28088 (format #t "Hello, friend! arguments: ~s\n"
28093 Assuming this action is added to the @code{example} service, then you can do:
28096 # herd say-hello example
28097 Hello, friend! arguments: ()
28098 # herd say-hello example a b c
28099 Hello, friend! arguments: ("a" "b" "c")
28102 This, as you can see, is a fairly sophisticated way to say hello.
28103 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
28107 @defvr {Scheme Variable} shepherd-root-service-type
28108 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
28110 This is the service type that extensions target when they want to create
28111 shepherd services (@pxref{Service Types and Services}, for an example).
28112 Each extension must pass a list of @code{<shepherd-service>}.
28115 @defvr {Scheme Variable} %shepherd-root-service
28116 This service represents PID@tie{}1.
28120 @node Documentation
28121 @chapter Documentation
28123 @cindex documentation, searching for
28124 @cindex searching for documentation
28125 @cindex Info, documentation format
28127 @cindex manual pages
28128 In most cases packages installed with Guix come with documentation.
28129 There are two main documentation formats: ``Info'', a browseable
28130 hypertext format used for GNU software, and ``manual pages'' (or ``man
28131 pages''), the linear documentation format traditionally found on Unix.
28132 Info manuals are accessed with the @command{info} command or with Emacs,
28133 and man pages are accessed using @command{man}.
28135 You can look for documentation of software installed on your system by
28136 keyword. For example, the following command searches for information
28137 about ``TLS'' in Info manuals:
28141 "(emacs)Network Security" -- STARTTLS
28142 "(emacs)Network Security" -- TLS
28143 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
28144 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
28149 The command below searches for the same keyword in man pages:
28153 SSL (7) - OpenSSL SSL/TLS library
28154 certtool (1) - GnuTLS certificate tool
28158 These searches are purely local to your computer so you have the
28159 guarantee that documentation you find corresponds to what you have
28160 actually installed, you can access it off-line, and your privacy is
28163 Once you have these results, you can view the relevant documentation by
28167 $ info "(gnutls)Core TLS API"
28177 Info manuals contain sections and indices as well as hyperlinks like
28178 those found in Web pages. The @command{info} reader (@pxref{Top, Info
28179 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
28180 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
28181 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
28182 Introduction}, for an introduction to Info navigation.
28184 @node Installing Debugging Files
28185 @chapter Installing Debugging Files
28187 @cindex debugging files
28188 Program binaries, as produced by the GCC compilers for instance, are
28189 typically written in the ELF format, with a section containing
28190 @dfn{debugging information}. Debugging information is what allows the
28191 debugger, GDB, to map binary code to source code; it is required to
28192 debug a compiled program in good conditions.
28194 The problem with debugging information is that is takes up a fair amount
28195 of disk space. For example, debugging information for the GNU C Library
28196 weighs in at more than 60 MiB. Thus, as a user, keeping all the
28197 debugging info of all the installed programs is usually not an option.
28198 Yet, space savings should not come at the cost of an impediment to
28199 debugging---especially in the GNU system, which should make it easier
28200 for users to exert their computing freedom (@pxref{GNU Distribution}).
28202 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
28203 mechanism that allows users to get the best of both worlds: debugging
28204 information can be stripped from the binaries and stored in separate
28205 files. GDB is then able to load debugging information from those files,
28206 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
28209 The GNU distribution takes advantage of this by storing debugging
28210 information in the @code{lib/debug} sub-directory of a separate package
28211 output unimaginatively called @code{debug} (@pxref{Packages with
28212 Multiple Outputs}). Users can choose to install the @code{debug} output
28213 of a package when they need it. For instance, the following command
28214 installs the debugging information for the GNU C Library and for GNU
28218 guix install glibc:debug guile:debug
28221 GDB must then be told to look for debug files in the user's profile, by
28222 setting the @code{debug-file-directory} variable (consider setting it
28223 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
28227 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
28230 From there on, GDB will pick up debugging information from the
28231 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
28233 In addition, you will most likely want GDB to be able to show the source
28234 code being debugged. To do that, you will have to unpack the source
28235 code of the package of interest (obtained with @code{guix build
28236 --source}, @pxref{Invoking guix build}), and to point GDB to that source
28237 directory using the @code{directory} command (@pxref{Source Path,
28238 @code{directory},, gdb, Debugging with GDB}).
28240 @c XXX: keep me up-to-date
28241 The @code{debug} output mechanism in Guix is implemented by the
28242 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
28243 opt-in---debugging information is available only for the packages
28244 with definitions explicitly declaring a @code{debug} output. This may be
28245 changed to opt-out in the future if our build farm servers can handle
28246 the load. To check whether a package has a @code{debug} output, use
28247 @command{guix package --list-available} (@pxref{Invoking guix package}).
28250 @node Security Updates
28251 @chapter Security Updates
28253 @cindex security updates
28254 @cindex security vulnerabilities
28255 Occasionally, important security vulnerabilities are discovered in software
28256 packages and must be patched. Guix developers try hard to keep track of
28257 known vulnerabilities and to apply fixes as soon as possible in the
28258 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
28259 containing only security updates.) The @command{guix lint} tool helps
28260 developers find out about vulnerable versions of software packages in the
28265 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
28266 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
28267 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
28271 @xref{Invoking guix lint}, for more information.
28273 Guix follows a functional
28274 package management discipline (@pxref{Introduction}), which implies
28275 that, when a package is changed, @emph{every package that depends on it}
28276 must be rebuilt. This can significantly slow down the deployment of
28277 fixes in core packages such as libc or Bash, since basically the whole
28278 distribution would need to be rebuilt. Using pre-built binaries helps
28279 (@pxref{Substitutes}), but deployment may still take more time than
28283 To address this, Guix implements @dfn{grafts}, a mechanism that allows
28284 for fast deployment of critical updates without the costs associated
28285 with a whole-distribution rebuild. The idea is to rebuild only the
28286 package that needs to be patched, and then to ``graft'' it onto packages
28287 explicitly installed by the user and that were previously referring to
28288 the original package. The cost of grafting is typically very low, and
28289 order of magnitudes lower than a full rebuild of the dependency chain.
28291 @cindex replacements of packages, for grafts
28292 For instance, suppose a security update needs to be applied to Bash.
28293 Guix developers will provide a package definition for the ``fixed''
28294 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
28295 Packages}). Then, the original package definition is augmented with a
28296 @code{replacement} field pointing to the package containing the bug fix:
28303 (replacement bash-fixed)))
28306 From there on, any package depending directly or indirectly on Bash---as
28307 reported by @command{guix gc --requisites} (@pxref{Invoking guix
28308 gc})---that is installed is automatically ``rewritten'' to refer to
28309 @code{bash-fixed} instead of @code{bash}. This grafting process takes
28310 time proportional to the size of the package, usually less than a
28311 minute for an ``average'' package on a recent machine. Grafting is
28312 recursive: when an indirect dependency requires grafting, then grafting
28313 ``propagates'' up to the package that the user is installing.
28315 Currently, the length of the name and version of the graft and that of
28316 the package it replaces (@code{bash-fixed} and @code{bash} in the example
28317 above) must be equal. This restriction mostly comes from the fact that
28318 grafting works by patching files, including binary files, directly.
28319 Other restrictions may apply: for instance, when adding a graft to a
28320 package providing a shared library, the original shared library and its
28321 replacement must have the same @code{SONAME} and be binary-compatible.
28323 The @option{--no-grafts} command-line option allows you to forcefully
28324 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
28328 guix build bash --no-grafts
28332 returns the store file name of the original Bash, whereas:
28339 returns the store file name of the ``fixed'', replacement Bash. This
28340 allows you to distinguish between the two variants of Bash.
28342 To verify which Bash your whole profile refers to, you can run
28343 (@pxref{Invoking guix gc}):
28346 guix gc -R `readlink -f ~/.guix-profile` | grep bash
28350 @dots{} and compare the store file names that you get with those above.
28351 Likewise for a complete Guix system generation:
28354 guix gc -R `guix system build my-config.scm` | grep bash
28357 Lastly, to check which Bash running processes are using, you can use the
28358 @command{lsof} command:
28361 lsof | grep /gnu/store/.*bash
28365 @node Bootstrapping
28366 @chapter Bootstrapping
28368 @c Adapted from the ELS 2013 paper.
28370 @cindex bootstrapping
28372 Bootstrapping in our context refers to how the distribution gets built
28373 ``from nothing''. Remember that the build environment of a derivation
28374 contains nothing but its declared inputs (@pxref{Introduction}). So
28375 there's an obvious chicken-and-egg problem: how does the first package
28376 get built? How does the first compiler get compiled? Note that this is
28377 a question of interest only to the curious hacker, not to the regular
28378 user, so you can shamelessly skip this section if you consider yourself
28379 a ``regular user''.
28381 @cindex bootstrap binaries
28382 The GNU system is primarily made of C code, with libc at its core. The
28383 GNU build system itself assumes the availability of a Bourne shell and
28384 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
28385 `grep'. Furthermore, build programs---programs that run
28386 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
28387 (@pxref{Derivations}). Consequently, to be able to build anything at
28388 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
28389 Binutils, libc, and the other packages mentioned above---the
28390 @dfn{bootstrap binaries}.
28392 These bootstrap binaries are ``taken for granted'', though we can also
28393 re-create them if needed (more on that later).
28395 For @code{i686-linux} and @code{x86_64-linux} the Guix bootstrap process is
28396 more elaborate, @pxref{Reduced Binary Seed Bootstrap}.
28399 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
28400 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
28403 @node Reduced Binary Seed Bootstrap
28404 @section The Reduced Binary Seed Bootstrap
28406 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
28407 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
28408 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
28409 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
28410 ``taken for granted.''
28412 Taking these binaries for granted means that we consider them to be a correct
28413 and trustworthy `seed' for building the complete system. Therein lies a
28414 problem: the current combined size of these bootstrap binaries is about 250MB
28415 (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing or even inspecting
28416 these is next to impossible.
28418 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a ``Reduced
28419 Binary Seed'' bootstrap @footnote{We would like to say: ``Full Source
28420 Bootstrap'' and while we are working towards that goal it would be hyperbole
28421 to use that term for what we do now.}.
28423 The Reduced Binary Seed bootstrap removes the most critical tools---from a
28424 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
28425 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
28426 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
28427 written in Scheme and the Mes C Library, built for TinyCC and for GCC). Using
28428 these new binary seeds and a new set of
28430 packages@footnote{@c
28445 gcc-mesboot1-wrapper,
28446 glibc-headers-mesboot,
28450 gcc-mesboot-wrapper.
28453 the ``missing'' Binutils, GCC, and the GNU C Library are built from source.
28454 From here on the more traditional bootstrap process resumes. This approach
28455 has reduced the bootstrap binaries in size to about 130MB. Work is ongoing to
28456 reduce this further. If you are interested, join us on @code{#bootstrappable}
28457 on the Freenode IRC network.
28459 @c ./pre-inst-env guix graph --type=bag -e '(begin (use-modules (guix packages)) (%current-system "i686-linux") (@@ (gnu packages commencement) gcc-mesboot))' > doc/images/gcc-mesboot-bag-graph.dot
28460 @c dot -T png doc/images/gcc-mesboot-bag-graph.dot > doc/images/gcc-mesboot-bag-graph.png
28462 Below is the generated dependency graph for @code{gcc-mesboot}, the bootstrap
28463 compiler used to build the rest of GuixSD.
28465 @image{images/gcc-mesboot-bag-graph,6in,,Dependency graph of the gcc-mesboot}
28467 @node Preparing to Use the Bootstrap Binaries
28468 @section Preparing to Use the Bootstrap Binaries
28470 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
28471 @c large image, it's hard to scroll. Oh well.
28472 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
28474 The figure above shows the very beginning of the dependency graph of the
28475 distribution, corresponding to the package definitions of the @code{(gnu
28476 packages bootstrap)} module. A similar figure can be generated with
28477 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
28480 guix graph -t derivation \
28481 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
28482 | dot -Tps > gcc.ps
28485 or, for the Reduced Binary Seed bootstrap
28488 guix graph -t derivation \
28489 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
28490 | dot -Tps > mes.ps
28493 At this level of detail, things are
28494 slightly complex. First, Guile itself consists of an ELF executable,
28495 along with many source and compiled Scheme files that are dynamically
28496 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
28497 tarball shown in this graph. This tarball is part of Guix's ``source''
28498 distribution, and gets inserted into the store with @code{add-to-store}
28499 (@pxref{The Store}).
28501 But how do we write a derivation that unpacks this tarball and adds it
28502 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
28503 derivation---the first one that gets built---uses @code{bash} as its
28504 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
28505 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
28506 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
28507 the Guix source distribution, whose sole purpose is to allow the Guile
28508 tarball to be unpacked.
28510 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
28511 Guile that can be used to run subsequent build programs. Its first task
28512 is to download tarballs containing the other pre-built binaries---this
28513 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
28514 @code{ftp-client.scm} are used for this purpose. The
28515 @code{module-import.drv} derivations import those modules in a directory
28516 in the store, using the original layout. The
28517 @code{module-import-compiled.drv} derivations compile those modules, and
28518 write them in an output directory with the right layout. This
28519 corresponds to the @code{#:modules} argument of
28520 @code{build-expression->derivation} (@pxref{Derivations}).
28522 Finally, the various tarballs are unpacked by the derivations
28523 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
28524 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
28525 point we have a working C tool chain.
28527 @unnumberedsec Building the Build Tools
28529 Bootstrapping is complete when we have a full tool chain that does not
28530 depend on the pre-built bootstrap tools discussed above. This
28531 no-dependency requirement is verified by checking whether the files of
28532 the final tool chain contain references to the @file{/gnu/store}
28533 directories of the bootstrap inputs. The process that leads to this
28534 ``final'' tool chain is described by the package definitions found in
28535 the @code{(gnu packages commencement)} module.
28537 The @command{guix graph} command allows us to ``zoom out'' compared to
28538 the graph above, by looking at the level of package objects instead of
28539 individual derivations---remember that a package may translate to
28540 several derivations, typically one derivation to download its source,
28541 one to build the Guile modules it needs, and one to actually build the
28542 package from source. The command:
28545 guix graph -t bag \
28546 -e '(@@@@ (gnu packages commencement)
28547 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
28551 produces the dependency graph leading to the ``final'' C
28552 library@footnote{You may notice the @code{glibc-intermediate} label,
28553 suggesting that it is not @emph{quite} final, but as a good
28554 approximation, we will consider it final.}, depicted below.
28556 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
28558 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
28559 The first tool that gets built with the bootstrap binaries is
28560 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
28561 for all the following packages. From there Findutils and Diffutils get
28564 Then come the first-stage Binutils and GCC, built as pseudo cross
28565 tools---i.e., with @code{--target} equal to @code{--host}. They are
28566 used to build libc. Thanks to this cross-build trick, this libc is
28567 guaranteed not to hold any reference to the initial tool chain.
28569 From there the final Binutils and GCC (not shown above) are built.
28571 from the final Binutils, and links programs against the just-built libc.
28572 This tool chain is used to build the other packages used by Guix and by
28573 the GNU Build System: Guile, Bash, Coreutils, etc.
28575 And voilà! At this point we have the complete set of build tools that
28576 the GNU Build System expects. These are in the @code{%final-inputs}
28577 variable of the @code{(gnu packages commencement)} module, and are
28578 implicitly used by any package that uses @code{gnu-build-system}
28579 (@pxref{Build Systems, @code{gnu-build-system}}).
28582 @unnumberedsec Building the Bootstrap Binaries
28584 @cindex bootstrap binaries
28585 Because the final tool chain does not depend on the bootstrap binaries,
28586 those rarely need to be updated. Nevertheless, it is useful to have an
28587 automated way to produce them, should an update occur, and this is what
28588 the @code{(gnu packages make-bootstrap)} module provides.
28590 The following command builds the tarballs containing the bootstrap binaries
28591 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
28592 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
28593 and Guile, and a tarball containing a mixture of Coreutils and other basic
28594 command-line tools):
28597 guix build bootstrap-tarballs
28600 The generated tarballs are those that should be referred to in the
28601 @code{(gnu packages bootstrap)} module mentioned at the beginning of
28604 Still here? Then perhaps by now you've started to wonder: when do we
28605 reach a fixed point? That is an interesting question! The answer is
28606 unknown, but if you would like to investigate further (and have
28607 significant computational and storage resources to do so), then let us
28610 @unnumberedsec Reducing the Set of Bootstrap Binaries
28612 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
28613 binary code! Why is that a problem? It's a problem because these big chunks
28614 of binary code are practically non-auditable, which makes it hard to establish
28615 what source code produced them. Every unauditable binary also leaves us
28616 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
28617 paper @emph{Reflections on Trusting Trust}.
28619 This is mitigated by the fact that our bootstrap binaries were generated
28620 from an earlier Guix revision. Nevertheless it lacks the level of
28621 transparency that we get in the rest of the package dependency graph,
28622 where Guix always gives us a source-to-binary mapping. Thus, our goal
28623 is to reduce the set of bootstrap binaries to the bare minimum.
28625 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
28626 on-going projects to do that. One of these is about replacing the
28627 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
28628 of increasing complexity, which could be built from source starting from
28629 a simple and auditable assembler.
28631 Our first major achievement is the replacement of of GCC, the GNU C Library
28632 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
28633 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
28634 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
28635 bootstrapped yet and thus we inject them as binary seeds. We call this the
28636 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
28637 binaries! Also, it has eliminated the C compiler binary; i686-linux and
28638 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
28640 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
28641 also looking at any other bootstrap binaries. Your help is welcome!
28644 @chapter Porting to a New Platform
28646 As discussed above, the GNU distribution is self-contained, and
28647 self-containment is achieved by relying on pre-built ``bootstrap
28648 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
28649 operating system kernel, CPU architecture, and application binary
28650 interface (ABI). Thus, to port the distribution to a platform that is
28651 not yet supported, one must build those bootstrap binaries, and update
28652 the @code{(gnu packages bootstrap)} module to use them on that platform.
28654 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
28655 When everything goes well, and assuming the GNU tool chain supports the
28656 target platform, this can be as simple as running a command like this
28660 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
28663 For this to work, the @code{glibc-dynamic-linker} procedure in
28664 @code{(gnu packages bootstrap)} must be augmented to return the right
28665 file name for libc's dynamic linker on that platform; likewise,
28666 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
28667 taught about the new platform.
28669 Once these are built, the @code{(gnu packages bootstrap)} module needs
28670 to be updated to refer to these binaries on the target platform. That
28671 is, the hashes and URLs of the bootstrap tarballs for the new platform
28672 must be added alongside those of the currently supported platforms. The
28673 bootstrap Guile tarball is treated specially: it is expected to be
28674 available locally, and @file{gnu/local.mk} has rules to download it for
28675 the supported architectures; a rule for the new platform must be added
28678 In practice, there may be some complications. First, it may be that the
28679 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
28680 above) is not recognized by all the GNU tools. Typically, glibc
28681 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
28682 configure flag (see @code{gcc.scm} for examples of how to handle this).
28683 Second, some of the required packages could fail to build for that
28684 platform. Lastly, the generated binaries could be broken for some
28687 @c *********************************************************************
28688 @include contributing.texi
28690 @c *********************************************************************
28691 @node Acknowledgments
28692 @chapter Acknowledgments
28694 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
28695 which was designed and
28696 implemented by Eelco Dolstra, with contributions from other people (see
28697 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
28698 management, and promoted unprecedented features, such as transactional
28699 package upgrades and rollbacks, per-user profiles, and referentially
28700 transparent build processes. Without this work, Guix would not exist.
28702 The Nix-based software distributions, Nixpkgs and NixOS, have also been
28703 an inspiration for Guix.
28705 GNU@tie{}Guix itself is a collective work with contributions from a
28706 number of people. See the @file{AUTHORS} file in Guix for more
28707 information on these fine people. The @file{THANKS} file lists people
28708 who have helped by reporting bugs, taking care of the infrastructure,
28709 providing artwork and themes, making suggestions, and more---thank you!
28712 @c *********************************************************************
28713 @node GNU Free Documentation License
28714 @appendix GNU Free Documentation License
28715 @cindex license, GNU Free Documentation License
28716 @include fdl-1.3.texi
28718 @c *********************************************************************
28719 @node Concept Index
28720 @unnumbered Concept Index
28723 @node Programming Index
28724 @unnumbered Programming Index
28725 @syncodeindex tp fn
28726 @syncodeindex vr fn
28731 @c Local Variables:
28732 @c ispell-local-dictionary: "american";