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 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@*
82 Permission is granted to copy, distribute and/or modify this document
83 under the terms of the GNU Free Documentation License, Version 1.3 or
84 any later version published by the Free Software Foundation; with no
85 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
86 copy of the license is included in the section entitled ``GNU Free
87 Documentation License''.
90 @dircategory System administration
92 * Guix: (guix). Manage installed software and system configuration.
93 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
94 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
95 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
96 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
97 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
100 @dircategory Software development
102 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
103 * guix build: (guix)Invoking guix build. Building packages.
104 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
108 @title GNU Guix Reference Manual
109 @subtitle Using the GNU Guix Functional Package Manager
110 @author The GNU Guix Developers
113 @vskip 0pt plus 1filll
114 Edition @value{EDITION} @*
122 @c *********************************************************************
126 This document describes GNU Guix version @value{VERSION}, a functional
127 package management tool written for the GNU system.
129 @c TRANSLATORS: You can replace the following paragraph with information on
130 @c how to join your own translation team and how to report issues with the
132 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
133 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
134 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
135 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
136 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
137 would like to translate it in your native language, consider joining the
138 @uref{https://translationproject.org/domain/guix-manual.html, Translation
142 * Introduction:: What is Guix about?
143 * Installation:: Installing Guix.
144 * System Installation:: Installing the whole operating system.
145 * Package Management:: Package installation, upgrade, etc.
146 * Development:: Guix-aided software development.
147 * Programming Interface:: Using Guix in Scheme.
148 * Utilities:: Package management commands.
149 * System Configuration:: Configuring the operating system.
150 * Documentation:: Browsing software user manuals.
151 * Installing Debugging Files:: Feeding the debugger.
152 * Security Updates:: Deploying security fixes quickly.
153 * Bootstrapping:: GNU/Linux built from scratch.
154 * Porting:: Targeting another platform or kernel.
155 * Contributing:: Your help needed!
157 * Acknowledgments:: Thanks!
158 * GNU Free Documentation License:: The license of this manual.
159 * Concept Index:: Concepts.
160 * Programming Index:: Data types, functions, and variables.
163 --- The Detailed Node Listing ---
167 * Managing Software the Guix Way:: What's special.
168 * GNU Distribution:: The packages and tools.
172 * Binary Installation:: Getting Guix running in no time!
173 * Requirements:: Software needed to build and run Guix.
174 * Running the Test Suite:: Testing Guix.
175 * Setting Up the Daemon:: Preparing the build daemon's environment.
176 * Invoking guix-daemon:: Running the build daemon.
177 * Application Setup:: Application-specific setup.
179 Setting Up the Daemon
181 * Build Environment Setup:: Preparing the isolated build environment.
182 * Daemon Offload Setup:: Offloading builds to remote machines.
183 * SELinux Support:: Using an SELinux policy for the daemon.
187 * Limitations:: What you can expect.
188 * Hardware Considerations:: Supported hardware.
189 * USB Stick and DVD Installation:: Preparing the installation medium.
190 * Preparing for Installation:: Networking, partitioning, etc.
191 * Guided Graphical Installation:: Easy graphical installation.
192 * Manual Installation:: Manual installation for wizards.
193 * After System Installation:: When installation succeeded.
194 * Installing Guix in a VM:: Guix System playground.
195 * Building the Installation Image:: How this comes to be.
199 * Keyboard Layout and Networking and Partitioning:: Initial setup.
200 * Proceeding with the Installation:: Installing.
204 * Features:: How Guix will make your life brighter.
205 * Invoking guix package:: Package installation, removal, etc.
206 * Substitutes:: Downloading pre-built binaries.
207 * Packages with Multiple Outputs:: Single source package, multiple outputs.
208 * Invoking guix gc:: Running the garbage collector.
209 * Invoking guix pull:: Fetching the latest Guix and distribution.
210 * Channels:: Customizing the package collection.
211 * Invoking guix time-machine:: Running an older revision of Guix.
212 * Inferiors:: Interacting with another revision of Guix.
213 * Invoking guix describe:: Display information about your Guix revision.
214 * Invoking guix archive:: Exporting and importing store files.
218 * Official Substitute Server:: One particular source of substitutes.
219 * Substitute Server Authorization:: How to enable or disable substitutes.
220 * Substitute Authentication:: How Guix verifies substitutes.
221 * Proxy Settings:: How to get substitutes via proxy.
222 * Substitution Failure:: What happens when substitution fails.
223 * On Trusting Binaries:: How can you trust that binary blob?
227 * Invoking guix environment:: Setting up development environments.
228 * Invoking guix pack:: Creating software bundles.
230 Programming Interface
232 * Package Modules:: Packages from the programmer's viewpoint.
233 * Defining Packages:: Defining new packages.
234 * Build Systems:: Specifying how packages are built.
235 * The Store:: Manipulating the package store.
236 * Derivations:: Low-level interface to package derivations.
237 * The Store Monad:: Purely functional interface to the store.
238 * G-Expressions:: Manipulating build expressions.
239 * Invoking guix repl:: Fiddling with Guix interactively.
243 * package Reference:: The package data type.
244 * origin Reference:: The origin data type.
248 * Invoking guix build:: Building packages from the command line.
249 * Invoking guix edit:: Editing package definitions.
250 * Invoking guix download:: Downloading a file and printing its hash.
251 * Invoking guix hash:: Computing the cryptographic hash of a file.
252 * Invoking guix import:: Importing package definitions.
253 * Invoking guix refresh:: Updating package definitions.
254 * Invoking guix lint:: Finding errors in package definitions.
255 * Invoking guix size:: Profiling disk usage.
256 * Invoking guix graph:: Visualizing the graph of packages.
257 * Invoking guix publish:: Sharing substitutes.
258 * Invoking guix challenge:: Challenging substitute servers.
259 * Invoking guix copy:: Copying to and from a remote store.
260 * Invoking guix container:: Process isolation.
261 * Invoking guix weather:: Assessing substitute availability.
262 * Invoking guix processes:: Listing client processes.
264 Invoking @command{guix build}
266 * Common Build Options:: Build options for most commands.
267 * Package Transformation Options:: Creating variants of packages.
268 * Additional Build Options:: Options specific to 'guix build'.
269 * Debugging Build Failures:: Real life packaging experience.
273 * Using the Configuration System:: Customizing your GNU system.
274 * operating-system Reference:: Detail of operating-system declarations.
275 * File Systems:: Configuring file system mounts.
276 * Mapped Devices:: Block device extra processing.
277 * User Accounts:: Specifying user accounts.
278 * Keyboard Layout:: How the system interprets key strokes.
279 * Locales:: Language and cultural convention settings.
280 * Services:: Specifying system services.
281 * Setuid Programs:: Programs running with root privileges.
282 * X.509 Certificates:: Authenticating HTTPS servers.
283 * Name Service Switch:: Configuring libc's name service switch.
284 * Initial RAM Disk:: Linux-Libre bootstrapping.
285 * Bootloader Configuration:: Configuring the boot loader.
286 * Invoking guix system:: Instantiating a system configuration.
287 * Invoking guix deploy:: Deploying a system configuration to a remote host.
288 * Running Guix in a VM:: How to run Guix System in a virtual machine.
289 * Defining Services:: Adding new service definitions.
293 * Base Services:: Essential system services.
294 * Scheduled Job Execution:: The mcron service.
295 * Log Rotation:: The rottlog service.
296 * Networking Services:: Network setup, SSH daemon, etc.
297 * X Window:: Graphical display.
298 * Printing Services:: Local and remote printer support.
299 * Desktop Services:: D-Bus and desktop services.
300 * Sound Services:: ALSA and Pulseaudio services.
301 * Database Services:: SQL databases, key-value stores, etc.
302 * Mail Services:: IMAP, POP3, SMTP, and all that.
303 * Messaging Services:: Messaging services.
304 * Telephony Services:: Telephony services.
305 * Monitoring Services:: Monitoring services.
306 * Kerberos Services:: Kerberos services.
307 * Web Services:: Web servers.
308 * Certificate Services:: TLS certificates via Let's Encrypt.
309 * DNS Services:: DNS daemons.
310 * VPN Services:: VPN daemons.
311 * Network File System:: NFS related services.
312 * Continuous Integration:: The Cuirass service.
313 * Power Management Services:: Extending battery life.
314 * Audio Services:: The MPD.
315 * Virtualization Services:: Virtualization services.
316 * Version Control Services:: Providing remote access to Git repositories.
317 * Game Services:: Game servers.
318 * PAM Mount Service:: Service to mount volumes when logging in.
319 * Linux Services:: Services tied to the Linux kernel.
320 * Miscellaneous Services:: Other services.
324 * Service Composition:: The model for composing services.
325 * Service Types and Services:: Types and services.
326 * Service Reference:: API reference.
327 * Shepherd Services:: A particular type of service.
332 @c *********************************************************************
334 @chapter Introduction
337 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
338 using the international phonetic alphabet (IPA).} is a package
339 management tool for and distribution of the GNU system.
340 Guix makes it easy for unprivileged
341 users to install, upgrade, or remove software packages, to roll back to a
342 previous package set, to build packages from source, and generally
343 assists with the creation and maintenance of software environments.
346 @cindex GuixSD, now Guix System
347 @cindex Guix System Distribution, now Guix System
348 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
349 complements the available tools without interference (@pxref{Installation}),
350 or you can use it as a standalone operating system distribution,
351 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
352 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
353 group everything under the ``Guix'' banner since, after all, Guix System is
354 readily available through the @command{guix system} command, even if you're
355 using a different distro underneath!}. @xref{GNU Distribution}.
358 * Managing Software the Guix Way:: What's special.
359 * GNU Distribution:: The packages and tools.
362 @node Managing Software the Guix Way
363 @section Managing Software the Guix Way
365 @cindex user interfaces
366 Guix provides a command-line package management interface
367 (@pxref{Package Management}), tools to help with software development
368 (@pxref{Development}), command-line utilities for more advanced usage,
369 (@pxref{Utilities}), as well as Scheme programming interfaces
370 (@pxref{Programming Interface}).
372 Its @dfn{build daemon} is responsible for building packages on behalf of
373 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
374 binaries from authorized sources (@pxref{Substitutes}).
376 @cindex extensibility of the distribution
377 @cindex customization, of packages
378 Guix includes package definitions for many GNU and non-GNU packages, all
379 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
380 user's computing freedom}. It is @emph{extensible}: users can write
381 their own package definitions (@pxref{Defining Packages}) and make them
382 available as independent package modules (@pxref{Package Modules}). It
383 is also @emph{customizable}: users can @emph{derive} specialized package
384 definitions from existing ones, including from the command line
385 (@pxref{Package Transformation Options}).
387 @cindex functional package management
389 Under the hood, Guix implements the @dfn{functional package management}
390 discipline pioneered by Nix (@pxref{Acknowledgments}).
391 In Guix, the package build and installation process is seen
392 as a @emph{function}, in the mathematical sense. That function takes inputs,
393 such as build scripts, a compiler, and libraries, and
394 returns an installed package. As a pure function, its result depends
395 solely on its inputs---for instance, it cannot refer to software or
396 scripts that were not explicitly passed as inputs. A build function
397 always produces the same result when passed a given set of inputs. It
398 cannot alter the environment of the running system in
399 any way; for instance, it cannot create, modify, or delete files outside
400 of its build and installation directories. This is achieved by running
401 build processes in isolated environments (or @dfn{containers}), where only their
402 explicit inputs are visible.
405 The result of package build functions is @dfn{cached} in the file
406 system, in a special directory called @dfn{the store} (@pxref{The
407 Store}). Each package is installed in a directory of its own in the
408 store---by default under @file{/gnu/store}. The directory name contains
409 a hash of all the inputs used to build that package; thus, changing an
410 input yields a different directory name.
412 This approach is the foundation for the salient features of Guix: support
413 for transactional package upgrade and rollback, per-user installation, and
414 garbage collection of packages (@pxref{Features}).
417 @node GNU Distribution
418 @section GNU Distribution
421 Guix comes with a distribution of the GNU system consisting entirely of
422 free software@footnote{The term ``free'' here refers to the
423 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
424 users of that software}.}. The
425 distribution can be installed on its own (@pxref{System Installation}),
426 but it is also possible to install Guix as a package manager on top of
427 an installed GNU/Linux system (@pxref{Installation}). When we need to
428 distinguish between the two, we refer to the standalone distribution as
431 The distribution provides core GNU packages such as GNU libc, GCC, and
432 Binutils, as well as many GNU and non-GNU applications. The complete
433 list of available packages can be browsed
434 @url{https://www.gnu.org/software/guix/packages,on-line} or by
435 running @command{guix package} (@pxref{Invoking guix package}):
438 guix package --list-available
441 Our goal is to provide a practical 100% free software distribution of
442 Linux-based and other variants of GNU, with a focus on the promotion and
443 tight integration of GNU components, and an emphasis on programs and
444 tools that help users exert that freedom.
446 Packages are currently available on the following platforms:
451 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
454 Intel 32-bit architecture (IA32), Linux-Libre kernel;
457 ARMv7-A architecture with hard float, Thumb-2 and NEON,
458 using the EABI hard-float application binary interface (ABI),
459 and Linux-Libre kernel.
462 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
465 little-endian 64-bit MIPS processors, specifically the Loongson series,
466 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
467 supported; in particular, the project's build farms no longer provide
468 substitutes for this architecture.
472 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
473 configuration and Guix takes care of instantiating the configuration in a
474 transactional, reproducible, and stateless fashion (@pxref{System
475 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
476 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
477 Manual}), the well-known GNU utilities and tool chain, as well as the
478 graphical environment or system services of your choice.
480 Guix System is available on all the above platforms except
481 @code{mips64el-linux}.
484 For information on porting to other architectures or kernels,
487 Building this distribution is a cooperative effort, and you are invited
488 to join! @xref{Contributing}, for information about how you can help.
491 @c *********************************************************************
493 @chapter Installation
495 @cindex installing Guix
498 We recommend the use of this
499 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
500 shell installer script} to install Guix on top of a running GNU/Linux system,
501 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
502 with the installation of the package manager, which can be done on top of a
503 running GNU/Linux system. If, instead, you want to install the complete GNU
504 operating system, @pxref{System Installation}.} The script automates the
505 download, installation, and initial configuration of Guix. It should be run
509 @cindex foreign distro
510 @cindex directories related to foreign distro
511 When installed on a foreign distro, GNU@tie{}Guix complements the available
512 tools without interference. Its data lives exclusively in two directories,
513 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
514 such as @file{/etc}, are left untouched.
516 Once installed, Guix can be updated by running @command{guix pull}
517 (@pxref{Invoking guix pull}).
519 If you prefer to perform the installation steps manually or want to tweak
520 them, you may find the following subsections useful. They describe the
521 software requirements of Guix, as well as how to install it manually and get
525 * Binary Installation:: Getting Guix running in no time!
526 * Requirements:: Software needed to build and run Guix.
527 * Running the Test Suite:: Testing Guix.
528 * Setting Up the Daemon:: Preparing the build daemon's environment.
529 * Invoking guix-daemon:: Running the build daemon.
530 * Application Setup:: Application-specific setup.
531 * Upgrading Guix:: Upgrading Guix and its build daemon.
534 @node Binary Installation
535 @section Binary Installation
537 @cindex installing Guix from binaries
538 @cindex installer script
539 This section describes how to install Guix on an arbitrary system from a
540 self-contained tarball providing binaries for Guix and for all its
541 dependencies. This is often quicker than installing from source, which
542 is described in the next sections. The only requirement is to have
545 @c Note duplicated from the ``Installation'' node.
547 We recommend the use of this
548 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
549 shell installer script}. The script automates the download, installation, and
550 initial configuration steps described below. It should be run as the root
554 Installing goes along these lines:
558 @cindex downloading Guix binary
559 Download the binary tarball from
560 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz},
561 where @var{system} is @code{x86_64-linux} for an @code{x86_64} machine
562 already running the kernel Linux, and so on.
564 @c The following is somewhat duplicated in ``System Installation''.
565 Make sure to download the associated @file{.sig} file and to verify the
566 authenticity of the tarball against it, along these lines:
569 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
570 $ gpg --verify guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
573 If that command fails because you do not have the required public key,
574 then run this command to import it:
577 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
578 -qO - | gpg --import -
582 and rerun the @code{gpg --verify} command.
584 Take note that a warning like ``This key is not certified with a trusted
585 signature!'' is normal.
587 @c end authentication part
590 Now, you need to become the @code{root} user. Depending on your distribution,
591 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
595 # tar --warning=no-timestamp -xf \
596 /path/to/guix-binary-@value{VERSION}.@var{system}.tar.xz
597 # mv var/guix /var/ && mv gnu /
600 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
601 The latter contains a ready-to-use profile for @code{root} (see next
604 Do @emph{not} unpack the tarball on a working Guix system since that
605 would overwrite its own essential files.
607 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
608 not emit warnings about ``implausibly old time stamps'' (such
609 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
611 They stem from the fact that all the
612 files in the archive have their modification time set to zero (which
613 means January 1st, 1970.) This is done on purpose to make sure the
614 archive content is independent of its creation time, thus making it
618 Make the profile available under @file{~root/.config/guix/current}, which is
619 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
622 # mkdir -p ~root/.config/guix
623 # ln -sf /var/guix/profiles/per-user/root/current-guix \
624 ~root/.config/guix/current
627 Source @file{etc/profile} to augment @code{PATH} and other relevant
628 environment variables:
631 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
632 source $GUIX_PROFILE/etc/profile
636 Create the group and user accounts for build users as explained below
637 (@pxref{Build Environment Setup}).
640 Run the daemon, and set it to automatically start on boot.
642 If your host distro uses the systemd init system, this can be achieved
645 @c Versions of systemd that supported symlinked service files are not
646 @c yet widely deployed, so we should suggest that users copy the service
649 @c See this thread for more information:
650 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
653 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
655 # systemctl start guix-daemon && systemctl enable guix-daemon
658 If your host distro uses the Upstart init system:
661 # initctl reload-configuration
662 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
667 Otherwise, you can still start the daemon manually with:
670 # ~root/.config/guix/current/bin/guix-daemon \
671 --build-users-group=guixbuild
675 Make the @command{guix} command available to other users on the machine,
679 # mkdir -p /usr/local/bin
681 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
684 It is also a good idea to make the Info version of this manual available
688 # mkdir -p /usr/local/share/info
689 # cd /usr/local/share/info
690 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
694 That way, assuming @file{/usr/local/share/info} is in the search path,
695 running @command{info guix} will open this manual (@pxref{Other Info
696 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
700 @cindex substitutes, authorization thereof
701 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
702 (@pxref{Substitutes}), authorize them:
705 # guix archive --authorize < \
706 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
710 Each user may need to perform a few additional steps to make their Guix
711 environment ready for use, @pxref{Application Setup}.
714 Voilà, the installation is complete!
716 You can confirm that Guix is working by installing a sample package into
723 The binary installation tarball can be (re)produced and verified simply
724 by running the following command in the Guix source tree:
727 make guix-binary.@var{system}.tar.xz
731 ...@: which, in turn, runs:
734 guix pack -s @var{system} --localstatedir \
735 --profile-name=current-guix guix
738 @xref{Invoking guix pack}, for more info on this handy tool.
741 @section Requirements
743 This section lists requirements when building Guix from source. The
744 build procedure for Guix is the same as for other GNU software, and is
745 not covered here. Please see the files @file{README} and @file{INSTALL}
746 in the Guix source tree for additional details.
748 @cindex official website
749 GNU Guix is available for download from its website at
750 @url{https://www.gnu.org/software/guix/}.
752 GNU Guix depends on the following packages:
755 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
757 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
760 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
761 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
762 Guile,, gnutls-guile, GnuTLS-Guile});
764 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
767 @c FIXME: Specify a version number once a release has been made.
768 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
770 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON} 3.x;
771 @item @url{https://zlib.net, zlib};
772 @item @url{https://www.gnu.org/software/make/, GNU Make}.
775 The following dependencies are optional:
779 @c Note: We need at least 0.12.0 for 'userauth-gssapi!'.
780 Support for build offloading (@pxref{Daemon Offload Setup}) and
781 @command{guix copy} (@pxref{Invoking guix copy}) depends on
782 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
783 version 0.12.0 or later.
786 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
787 substitutes can be used and @command{guix publish} can compress substitutes
791 When @url{http://www.bzip.org, libbz2} is available,
792 @command{guix-daemon} can use it to compress build logs.
795 Unless @code{--disable-daemon} was passed to @command{configure}, the
796 following packages are also needed:
799 @item @url{https://gnupg.org/, GNU libgcrypt};
800 @item @url{https://sqlite.org, SQLite 3};
801 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
805 @cindex state directory
806 When configuring Guix on a system that already has a Guix installation,
807 be sure to specify the same state directory as the existing installation
808 using the @code{--localstatedir} option of the @command{configure}
809 script (@pxref{Directory Variables, @code{localstatedir},, standards,
810 GNU Coding Standards}). Usually, this @var{localstatedir} option is
811 set to the value @file{/var}. The @command{configure} script protects
812 against unintended misconfiguration of @var{localstatedir} so you do not
813 inadvertently corrupt your store (@pxref{The Store}).
815 @node Running the Test Suite
816 @section Running the Test Suite
819 After a successful @command{configure} and @code{make} run, it is a good
820 idea to run the test suite. It can help catch issues with the setup or
821 environment, or bugs in Guix itself---and really, reporting test
822 failures is a good way to help improve the software. To run the test
829 Test cases can run in parallel: you can use the @code{-j} option of
830 GNU@tie{}make to speed things up. The first run may take a few minutes
831 on a recent machine; subsequent runs will be faster because the store
832 that is created for test purposes will already have various things in
835 It is also possible to run a subset of the tests by defining the
836 @code{TESTS} makefile variable as in this example:
839 make check TESTS="tests/store.scm tests/cpio.scm"
842 By default, tests results are displayed at a file level. In order to
843 see the details of every individual test cases, it is possible to define
844 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
847 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
850 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
851 @file{test-suite.log} file. Please specify the Guix version being used
852 as well as version numbers of the dependencies (@pxref{Requirements}) in
855 Guix also comes with a whole-system test suite that tests complete
856 Guix System instances. It can only run on systems where
857 Guix is already installed, using:
864 or, again, by defining @code{TESTS} to select a subset of tests to run:
867 make check-system TESTS="basic mcron"
870 These system tests are defined in the @code{(gnu tests @dots{})}
871 modules. They work by running the operating systems under test with
872 lightweight instrumentation in a virtual machine (VM). They can be
873 computationally intensive or rather cheap, depending on whether
874 substitutes are available for their dependencies (@pxref{Substitutes}).
875 Some of them require a lot of storage space to hold VM images.
877 Again in case of test failures, please send @email{bug-guix@@gnu.org}
880 @node Setting Up the Daemon
881 @section Setting Up the Daemon
884 Operations such as building a package or running the garbage collector
885 are all performed by a specialized process, the @dfn{build daemon}, on
886 behalf of clients. Only the daemon may access the store and its
887 associated database. Thus, any operation that manipulates the store
888 goes through the daemon. For instance, command-line tools such as
889 @command{guix package} and @command{guix build} communicate with the
890 daemon (@i{via} remote procedure calls) to instruct it what to do.
892 The following sections explain how to prepare the build daemon's
893 environment. See also @ref{Substitutes}, for information on how to allow
894 the daemon to download pre-built binaries.
897 * Build Environment Setup:: Preparing the isolated build environment.
898 * Daemon Offload Setup:: Offloading builds to remote machines.
899 * SELinux Support:: Using an SELinux policy for the daemon.
902 @node Build Environment Setup
903 @subsection Build Environment Setup
905 @cindex build environment
906 In a standard multi-user setup, Guix and its daemon---the
907 @command{guix-daemon} program---are installed by the system
908 administrator; @file{/gnu/store} is owned by @code{root} and
909 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
910 Guix tools to build packages or otherwise access the store, and the
911 daemon will do it on their behalf, ensuring that the store is kept in a
912 consistent state, and allowing built packages to be shared among users.
915 When @command{guix-daemon} runs as @code{root}, you may not want package
916 build processes themselves to run as @code{root} too, for obvious
917 security reasons. To avoid that, a special pool of @dfn{build users}
918 should be created for use by build processes started by the daemon.
919 These build users need not have a shell and a home directory: they will
920 just be used when the daemon drops @code{root} privileges in build
921 processes. Having several such users allows the daemon to launch
922 distinct build processes under separate UIDs, which guarantees that they
923 do not interfere with each other---an essential feature since builds are
924 regarded as pure functions (@pxref{Introduction}).
926 On a GNU/Linux system, a build user pool may be created like this (using
927 Bash syntax and the @code{shadow} commands):
929 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
930 @c for why `-G' is needed.
932 # groupadd --system guixbuild
933 # for i in `seq -w 1 10`;
935 useradd -g guixbuild -G guixbuild \
936 -d /var/empty -s `which nologin` \
937 -c "Guix build user $i" --system \
943 The number of build users determines how many build jobs may run in
944 parallel, as specified by the @option{--max-jobs} option
945 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
946 @command{guix system vm} and related commands, you may need to add the
947 build users to the @code{kvm} group so they can access @file{/dev/kvm},
948 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
949 (@pxref{Invoking guix system}).
951 The @code{guix-daemon} program may then be run as @code{root} with the
952 following command@footnote{If your machine uses the systemd init system,
953 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
954 file in @file{/etc/systemd/system} will ensure that
955 @command{guix-daemon} is automatically started. Similarly, if your
956 machine uses the Upstart init system, drop the
957 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
958 file in @file{/etc/init}.}:
961 # guix-daemon --build-users-group=guixbuild
966 This way, the daemon starts build processes in a chroot, under one of
967 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
968 environment contains nothing but:
970 @c Keep this list in sync with libstore/build.cc! -----------------------
973 a minimal @code{/dev} directory, created mostly independently from the
974 host @code{/dev}@footnote{``Mostly'', because while the set of files
975 that appear in the chroot's @code{/dev} is fixed, most of these files
976 can only be created if the host has them.};
979 the @code{/proc} directory; it only shows the processes of the container
980 since a separate PID name space is used;
983 @file{/etc/passwd} with an entry for the current user and an entry for
987 @file{/etc/group} with an entry for the user's group;
990 @file{/etc/hosts} with an entry that maps @code{localhost} to
994 a writable @file{/tmp} directory.
997 You can influence the directory where the daemon stores build trees
998 @i{via} the @code{TMPDIR} environment variable. However, the build tree
999 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1000 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1001 This way, the value of @code{TMPDIR} does not leak inside build
1002 environments, which avoids discrepancies in cases where build processes
1003 capture the name of their build tree.
1006 The daemon also honors the @code{http_proxy} environment variable for
1007 HTTP downloads it performs, be it for fixed-output derivations
1008 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1010 If you are installing Guix as an unprivileged user, it is still possible
1011 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1012 However, build processes will not be isolated from one another, and not
1013 from the rest of the system. Thus, build processes may interfere with
1014 each other, and may access programs, libraries, and other files
1015 available on the system---making it much harder to view them as
1016 @emph{pure} functions.
1019 @node Daemon Offload Setup
1020 @subsection Using the Offload Facility
1024 When desired, the build daemon can @dfn{offload} derivation builds to
1025 other machines running Guix, using the @code{offload} @dfn{build
1026 hook}@footnote{This feature is available only when
1027 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1028 present.}. When that
1029 feature is enabled, a list of user-specified build machines is read from
1030 @file{/etc/guix/machines.scm}; every time a build is requested, for
1031 instance via @code{guix build}, the daemon attempts to offload it to one
1032 of the machines that satisfy the constraints of the derivation, in
1033 particular its system type---e.g., @file{x86_64-linux}. Missing
1034 prerequisites for the build are copied over SSH to the target machine,
1035 which then proceeds with the build; upon success the output(s) of the
1036 build are copied back to the initial machine.
1038 The @file{/etc/guix/machines.scm} file typically looks like this:
1041 (list (build-machine
1042 (name "eightysix.example.org")
1043 (system "x86_64-linux")
1044 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1046 (speed 2.)) ;incredibly fast!
1049 (name "meeps.example.org")
1050 (system "mips64el-linux")
1051 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1054 (string-append (getenv "HOME")
1055 "/.ssh/identity-for-guix"))))
1059 In the example above we specify a list of two build machines, one for
1060 the @code{x86_64} architecture and one for the @code{mips64el}
1063 In fact, this file is---not surprisingly!---a Scheme file that is
1064 evaluated when the @code{offload} hook is started. Its return value
1065 must be a list of @code{build-machine} objects. While this example
1066 shows a fixed list of build machines, one could imagine, say, using
1067 DNS-SD to return a list of potential build machines discovered in the
1068 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1069 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1072 @deftp {Data Type} build-machine
1073 This data type represents build machines to which the daemon may offload
1074 builds. The important fields are:
1079 The host name of the remote machine.
1082 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1085 The user account to use when connecting to the remote machine over SSH.
1086 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1087 allow non-interactive logins.
1090 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1091 This is used to authenticate the machine when we connect to it. It is a
1092 long string that looks like this:
1095 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1098 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1099 key can be found in a file such as
1100 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1102 If the machine is running the SSH daemon of GNU@tie{}lsh,
1103 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1104 similar file. It can be converted to the OpenSSH format using
1105 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1108 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1109 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1114 A number of optional fields may be specified:
1118 @item @code{port} (default: @code{22})
1119 Port number of SSH server on the machine.
1121 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1122 The SSH private key file to use when connecting to the machine, in
1123 OpenSSH format. This key must not be protected with a passphrase.
1125 Note that the default value is the private key @emph{of the root
1126 account}. Make sure it exists if you use the default.
1128 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1129 @itemx @code{compression-level} (default: @code{3})
1130 The SSH-level compression methods and compression level requested.
1132 Note that offloading relies on SSH compression to reduce bandwidth usage
1133 when transferring files to and from build machines.
1135 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1136 File name of the Unix-domain socket @command{guix-daemon} is listening
1139 @item @code{parallel-builds} (default: @code{1})
1140 The number of builds that may run in parallel on the machine.
1142 @item @code{speed} (default: @code{1.0})
1143 A ``relative speed factor''. The offload scheduler will tend to prefer
1144 machines with a higher speed factor.
1146 @item @code{features} (default: @code{'()})
1147 A list of strings denoting specific features supported by the machine.
1148 An example is @code{"kvm"} for machines that have the KVM Linux modules
1149 and corresponding hardware support. Derivations can request features by
1150 name, and they will be scheduled on matching build machines.
1155 The @command{guix} command must be in the search path on the build
1156 machines. You can check whether this is the case by running:
1159 ssh build-machine guix repl --version
1162 There is one last thing to do once @file{machines.scm} is in place. As
1163 explained above, when offloading, files are transferred back and forth
1164 between the machine stores. For this to work, you first need to
1165 generate a key pair on each machine to allow the daemon to export signed
1166 archives of files from the store (@pxref{Invoking guix archive}):
1169 # guix archive --generate-key
1173 Each build machine must authorize the key of the master machine so that
1174 it accepts store items it receives from the master:
1177 # guix archive --authorize < master-public-key.txt
1181 Likewise, the master machine must authorize the key of each build machine.
1183 All the fuss with keys is here to express pairwise mutual trust
1184 relations between the master and the build machines. Concretely, when
1185 the master receives files from a build machine (and @i{vice versa}), its
1186 build daemon can make sure they are genuine, have not been tampered
1187 with, and that they are signed by an authorized key.
1189 @cindex offload test
1190 To test whether your setup is operational, run this command on the
1197 This will attempt to connect to each of the build machines specified in
1198 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1199 available on each machine, attempt to export to the machine and import
1200 from it, and report any error in the process.
1202 If you want to test a different machine file, just specify it on the
1206 # guix offload test machines-qualif.scm
1209 Last, you can test the subset of the machines whose name matches a
1210 regular expression like this:
1213 # guix offload test machines.scm '\.gnu\.org$'
1216 @cindex offload status
1217 To display the current load of all build hosts, run this command on the
1221 # guix offload status
1225 @node SELinux Support
1226 @subsection SELinux Support
1228 @cindex SELinux, daemon policy
1229 @cindex mandatory access control, SELinux
1230 @cindex security, guix-daemon
1231 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1232 can be installed on a system where SELinux is enabled, in order to label
1233 Guix files and to specify the expected behavior of the daemon. Since
1234 Guix System does not provide an SELinux base policy, the daemon policy cannot
1235 be used on Guix System.
1237 @subsubsection Installing the SELinux policy
1238 @cindex SELinux, policy installation
1239 To install the policy run this command as root:
1242 semodule -i etc/guix-daemon.cil
1245 Then relabel the file system with @code{restorecon} or by a different
1246 mechanism provided by your system.
1248 Once the policy is installed, the file system has been relabeled, and
1249 the daemon has been restarted, it should be running in the
1250 @code{guix_daemon_t} context. You can confirm this with the following
1254 ps -Zax | grep guix-daemon
1257 Monitor the SELinux log files as you run a command like @code{guix build
1258 hello} to convince yourself that SELinux permits all necessary
1261 @subsubsection Limitations
1262 @cindex SELinux, limitations
1264 This policy is not perfect. Here is a list of limitations or quirks
1265 that should be considered when deploying the provided SELinux policy for
1270 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1271 operations involve contexts that have anything to do with
1272 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1273 but it would be preferrable to define socket rules for only this label.
1276 @code{guix gc} cannot access arbitrary links to profiles. By design,
1277 the file label of the destination of a symlink is independent of the
1278 file label of the link itself. Although all profiles under
1279 $localstatedir are labelled, the links to these profiles inherit the
1280 label of the directory they are in. For links in the user’s home
1281 directory this will be @code{user_home_t}. But for links from the root
1282 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1283 directory, etc, this won’t work. @code{guix gc} would be prevented from
1284 reading and following these links.
1287 The daemon’s feature to listen for TCP connections might no longer work.
1288 This might require extra rules, because SELinux treats network sockets
1289 differently from files.
1292 Currently all files with a name matching the regular expression
1293 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1294 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1295 that name in any profile would be permitted to run in the
1296 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1297 build a package that provides this executable and convince a user to
1298 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1299 At that point SELinux could not prevent it from accessing files that are
1300 allowed for processes in that domain.
1302 We could generate a much more restrictive policy at installation time,
1303 so that only the @emph{exact} file name of the currently installed
1304 @code{guix-daemon} executable would be labelled with
1305 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1306 The downside is that root would have to install or upgrade the policy at
1307 installation time whenever the Guix package that provides the
1308 effectively running @code{guix-daemon} executable is upgraded.
1311 @node Invoking guix-daemon
1312 @section Invoking @command{guix-daemon}
1314 The @command{guix-daemon} program implements all the functionality to
1315 access the store. This includes launching build processes, running the
1316 garbage collector, querying the availability of a build result, etc. It
1317 is normally run as @code{root} like this:
1320 # guix-daemon --build-users-group=guixbuild
1324 For details on how to set it up, @pxref{Setting Up the Daemon}.
1327 @cindex container, build environment
1328 @cindex build environment
1329 @cindex reproducible builds
1330 By default, @command{guix-daemon} launches build processes under
1331 different UIDs, taken from the build group specified with
1332 @code{--build-users-group}. In addition, each build process is run in a
1333 chroot environment that only contains the subset of the store that the
1334 build process depends on, as specified by its derivation
1335 (@pxref{Programming Interface, derivation}), plus a set of specific
1336 system directories. By default, the latter contains @file{/dev} and
1337 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1338 @dfn{container}: in addition to having its own file system tree, it has
1339 a separate mount name space, its own PID name space, network name space,
1340 etc. This helps achieve reproducible builds (@pxref{Features}).
1342 When the daemon performs a build on behalf of the user, it creates a
1343 build directory under @file{/tmp} or under the directory specified by
1344 its @code{TMPDIR} environment variable. This directory is shared with
1345 the container for the duration of the build, though within the container,
1346 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1348 The build directory is automatically deleted upon completion, unless the
1349 build failed and the client specified @option{--keep-failed}
1350 (@pxref{Invoking guix build, @option{--keep-failed}}).
1352 The daemon listens for connections and spawns one sub-process for each session
1353 started by a client (one of the @command{guix} sub-commands.) The
1354 @command{guix processes} command allows you to get an overview of the activity
1355 on your system by viewing each of the active sessions and clients.
1356 @xref{Invoking guix processes}, for more information.
1358 The following command-line options are supported:
1361 @item --build-users-group=@var{group}
1362 Take users from @var{group} to run build processes (@pxref{Setting Up
1363 the Daemon, build users}).
1365 @item --no-substitutes
1367 Do not use substitutes for build products. That is, always build things
1368 locally instead of allowing downloads of pre-built binaries
1369 (@pxref{Substitutes}).
1371 When the daemon runs with @code{--no-substitutes}, clients can still
1372 explicitly enable substitution @i{via} the @code{set-build-options}
1373 remote procedure call (@pxref{The Store}).
1375 @item --substitute-urls=@var{urls}
1376 @anchor{daemon-substitute-urls}
1377 Consider @var{urls} the default whitespace-separated list of substitute
1378 source URLs. When this option is omitted,
1379 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1381 This means that substitutes may be downloaded from @var{urls}, as long
1382 as they are signed by a trusted signature (@pxref{Substitutes}).
1386 Do not use offload builds to other machines (@pxref{Daemon Offload
1387 Setup}). That is, always build things locally instead of offloading
1388 builds to remote machines.
1390 @item --cache-failures
1391 Cache build failures. By default, only successful builds are cached.
1393 When this option is used, @command{guix gc --list-failures} can be used
1394 to query the set of store items marked as failed; @command{guix gc
1395 --clear-failures} removes store items from the set of cached failures.
1396 @xref{Invoking guix gc}.
1398 @item --cores=@var{n}
1400 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1403 The default value is @code{0}, but it may be overridden by clients, such
1404 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1407 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1408 in the build process, which can then use it to exploit internal
1409 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1411 @item --max-jobs=@var{n}
1413 Allow at most @var{n} build jobs in parallel. The default value is
1414 @code{1}. Setting it to @code{0} means that no builds will be performed
1415 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1416 Setup}), or simply fail.
1418 @item --max-silent-time=@var{seconds}
1419 When the build or substitution process remains silent for more than
1420 @var{seconds}, terminate it and report a build failure.
1422 The default value is @code{0}, which disables the timeout.
1424 The value specified here can be overridden by clients (@pxref{Common
1425 Build Options, @code{--max-silent-time}}).
1427 @item --timeout=@var{seconds}
1428 Likewise, when the build or substitution process lasts for more than
1429 @var{seconds}, terminate it and report a build failure.
1431 The default value is @code{0}, which disables the timeout.
1433 The value specified here can be overridden by clients (@pxref{Common
1434 Build Options, @code{--timeout}}).
1436 @item --rounds=@var{N}
1437 Build each derivation @var{n} times in a row, and raise an error if
1438 consecutive build results are not bit-for-bit identical. Note that this
1439 setting can be overridden by clients such as @command{guix build}
1440 (@pxref{Invoking guix build}).
1442 When used in conjunction with @option{--keep-failed}, the differing
1443 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1444 This makes it easy to look for differences between the two results.
1447 Produce debugging output.
1449 This is useful to debug daemon start-up issues, but then it may be
1450 overridden by clients, for example the @code{--verbosity} option of
1451 @command{guix build} (@pxref{Invoking guix build}).
1453 @item --chroot-directory=@var{dir}
1454 Add @var{dir} to the build chroot.
1456 Doing this may change the result of build processes---for instance if
1457 they use optional dependencies found in @var{dir} when it is available,
1458 and not otherwise. For that reason, it is not recommended to do so.
1459 Instead, make sure that each derivation declares all the inputs that it
1462 @item --disable-chroot
1463 Disable chroot builds.
1465 Using this option is not recommended since, again, it would allow build
1466 processes to gain access to undeclared dependencies. It is necessary,
1467 though, when @command{guix-daemon} is running under an unprivileged user
1470 @item --log-compression=@var{type}
1471 Compress build logs according to @var{type}, one of @code{gzip},
1472 @code{bzip2}, or @code{none}.
1474 Unless @code{--lose-logs} is used, all the build logs are kept in the
1475 @var{localstatedir}. To save space, the daemon automatically compresses
1476 them with bzip2 by default.
1478 @item --disable-deduplication
1479 @cindex deduplication
1480 Disable automatic file ``deduplication'' in the store.
1482 By default, files added to the store are automatically ``deduplicated'':
1483 if a newly added file is identical to another one found in the store,
1484 the daemon makes the new file a hard link to the other file. This can
1485 noticeably reduce disk usage, at the expense of slightly increased
1486 input/output load at the end of a build process. This option disables
1489 @item --gc-keep-outputs[=yes|no]
1490 Tell whether the garbage collector (GC) must keep outputs of live
1494 @cindex garbage collector roots
1495 When set to ``yes'', the GC will keep the outputs of any live derivation
1496 available in the store---the @code{.drv} files. The default is ``no'',
1497 meaning that derivation outputs are kept only if they are reachable from a GC
1498 root. @xref{Invoking guix gc}, for more on GC roots.
1500 @item --gc-keep-derivations[=yes|no]
1501 Tell whether the garbage collector (GC) must keep derivations
1502 corresponding to live outputs.
1504 When set to ``yes'', as is the case by default, the GC keeps
1505 derivations---i.e., @code{.drv} files---as long as at least one of their
1506 outputs is live. This allows users to keep track of the origins of
1507 items in their store. Setting it to ``no'' saves a bit of disk space.
1509 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1510 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1511 ``yes'' causes liveness to flow from derivations to outputs. When both are
1512 set to ``yes'', the effect is to keep all the build prerequisites (the
1513 sources, compiler, libraries, and other build-time tools) of live objects in
1514 the store, regardless of whether these prerequisites are reachable from a GC
1515 root. This is convenient for developers since it saves rebuilds or downloads.
1517 @item --impersonate-linux-2.6
1518 On Linux-based systems, impersonate Linux 2.6. This means that the
1519 kernel's @code{uname} system call will report 2.6 as the release number.
1521 This might be helpful to build programs that (usually wrongfully) depend
1522 on the kernel version number.
1525 Do not keep build logs. By default they are kept under
1526 @code{@var{localstatedir}/guix/log}.
1528 @item --system=@var{system}
1529 Assume @var{system} as the current system type. By default it is the
1530 architecture/kernel pair found at configure time, such as
1531 @code{x86_64-linux}.
1533 @item --listen=@var{endpoint}
1534 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1535 as the file name of a Unix-domain socket if it starts with
1536 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1537 host name or host name and port to listen to. Here are a few examples:
1540 @item --listen=/gnu/var/daemon
1541 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1542 creating it if needed.
1544 @item --listen=localhost
1545 @cindex daemon, remote access
1546 @cindex remote access to the daemon
1547 @cindex daemon, cluster setup
1548 @cindex clusters, daemon setup
1549 Listen for TCP connections on the network interface corresponding to
1550 @code{localhost}, on port 44146.
1552 @item --listen=128.0.0.42:1234
1553 Listen for TCP connections on the network interface corresponding to
1554 @code{128.0.0.42}, on port 1234.
1557 This option can be repeated multiple times, in which case
1558 @command{guix-daemon} accepts connections on all the specified
1559 endpoints. Users can tell client commands what endpoint to connect to
1560 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1561 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1564 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1565 @code{--listen=@var{host}} is suitable on local networks, such as
1566 clusters, where only trusted nodes may connect to the build daemon. In
1567 other cases where remote access to the daemon is needed, we recommend
1568 using Unix-domain sockets along with SSH.
1571 When @code{--listen} is omitted, @command{guix-daemon} listens for
1572 connections on the Unix-domain socket located at
1573 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1577 @node Application Setup
1578 @section Application Setup
1580 @cindex foreign distro
1581 When using Guix on top of GNU/Linux distribution other than Guix System---a
1582 so-called @dfn{foreign distro}---a few additional steps are needed to
1583 get everything in place. Here are some of them.
1587 @anchor{locales-and-locpath}
1588 @cindex locales, when not on Guix System
1590 @vindex GUIX_LOCPATH
1591 Packages installed @i{via} Guix will not use the locale data of the
1592 host system. Instead, you must first install one of the locale packages
1593 available with Guix and then define the @code{GUIX_LOCPATH} environment
1597 $ guix install glibc-locales
1598 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1601 Note that the @code{glibc-locales} package contains data for all the
1602 locales supported by the GNU@tie{}libc and weighs in at around
1603 917@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1604 limited to a few UTF-8 locales.
1606 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1607 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1608 Manual}). There are two important differences though:
1612 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1613 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1614 to make sure the programs of the foreign distro will not end up loading
1615 incompatible locale data.
1618 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1619 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1620 should your Guix profile contain a mixture of programs linked against
1621 different libc version, each libc version will only try to load locale
1622 data in the right format.
1625 This is important because the locale data format used by different libc
1626 versions may be incompatible.
1628 @subsection Name Service Switch
1630 @cindex name service switch, glibc
1631 @cindex NSS (name service switch), glibc
1632 @cindex nscd (name service caching daemon)
1633 @cindex name service caching daemon (nscd)
1634 When using Guix on a foreign distro, we @emph{strongly recommend} that
1635 the system run the GNU C library's @dfn{name service cache daemon},
1636 @command{nscd}, which should be listening on the
1637 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1638 installed with Guix may fail to look up host names or user accounts, or
1639 may even crash. The next paragraphs explain why.
1641 @cindex @file{nsswitch.conf}
1642 The GNU C library implements a @dfn{name service switch} (NSS), which is
1643 an extensible mechanism for ``name lookups'' in general: host name
1644 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1645 The GNU C Library Reference Manual}).
1647 @cindex Network information service (NIS)
1648 @cindex NIS (Network information service)
1649 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1650 lookup implementations: for example, the @code{nss-mdns} plugin allow
1651 resolution of @code{.local} host names, the @code{nis} plugin allows
1652 user account lookup using the Network information service (NIS), and so
1653 on. These extra ``lookup services'' are configured system-wide in
1654 @file{/etc/nsswitch.conf}, and all the programs running on the system
1655 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1658 When they perform a name lookup---for instance by calling the
1659 @code{getaddrinfo} function in C---applications first try to connect to
1660 the nscd; on success, nscd performs name lookups on their behalf. If
1661 the nscd is not running, then they perform the name lookup by
1662 themselves, by loading the name lookup services into their own address
1663 space and running it. These name lookup services---the
1664 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1665 the host system's C library, rather than from the C library the
1666 application is linked against (the C library coming from Guix).
1668 And this is where the problem is: if your application is linked against
1669 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1670 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1671 likely crash or have its name lookups fail unexpectedly.
1673 Running @command{nscd} on the system, among other advantages, eliminates
1674 this binary incompatibility problem because those @code{libnss_*.so}
1675 files are loaded in the @command{nscd} process, not in applications
1678 @subsection X11 Fonts
1681 The majority of graphical applications use Fontconfig to locate and
1682 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1683 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1684 by default. Thus, to allow graphical applications installed with Guix
1685 to display fonts, you have to install fonts with Guix as well.
1686 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1687 @code{font-gnu-freefont-ttf}.
1689 @cindex @code{fc-cache}
1691 Once you have installed or removed fonts, or when you notice an
1692 application that does not find fonts, you may need to install Fontconfig
1693 and to force an update of its font cache by running:
1696 guix install fontconfig
1700 To display text written in Chinese languages, Japanese, or Korean in
1701 graphical applications, consider installing
1702 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1703 has multiple outputs, one per language family (@pxref{Packages with
1704 Multiple Outputs}). For instance, the following command installs fonts
1705 for Chinese languages:
1708 guix install font-adobe-source-han-sans:cn
1711 @cindex @code{xterm}
1712 Older programs such as @command{xterm} do not use Fontconfig and instead
1713 rely on server-side font rendering. Such programs require to specify a
1714 full name of a font using XLFD (X Logical Font Description), like this:
1717 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1720 To be able to use such full names for the TrueType fonts installed in
1721 your Guix profile, you need to extend the font path of the X server:
1723 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1724 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1726 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1729 @cindex @code{xlsfonts}
1730 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1731 to make sure your TrueType fonts are listed there.
1734 @subsection X.509 Certificates
1736 @cindex @code{nss-certs}
1737 The @code{nss-certs} package provides X.509 certificates, which allow
1738 programs to authenticate Web servers accessed over HTTPS.
1740 When using Guix on a foreign distro, you can install this package and
1741 define the relevant environment variables so that packages know where to
1742 look for certificates. @xref{X.509 Certificates}, for detailed
1745 @subsection Emacs Packages
1747 @cindex @code{emacs}
1748 When you install Emacs packages with Guix, the Elisp files are placed
1749 under the @file{share/emacs/site-lisp/} directory of the profile in
1750 which they are installed. The Elisp libraries are made available to
1751 Emacs through the @code{EMACSLOADPATH} environment variable, which is
1752 set when installing Emacs itself.
1754 Additionally, autoload definitions are automatically evaluated at the
1755 initialization of Emacs, by the Guix-specific
1756 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1757 want to avoid auto-loading the Emacs packages installed with Guix, you
1758 can do so by running Emacs with the @code{--no-site-file} option
1759 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1761 @subsection The GCC toolchain
1766 Guix offers individual compiler packages such as @code{gcc} but if you
1767 are in need of a complete toolchain for compiling and linking source
1768 code what you really want is the @code{gcc-toolchain} package. This
1769 package provides a complete GCC toolchain for C/C++ development,
1770 including GCC itself, the GNU C Library (headers and binaries, plus
1771 debugging symbols in the @code{debug} output), Binutils, and a linker
1774 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
1775 passed to the linker, add corresponding @code{-rpath} arguments, and
1776 invoke the actual linker with this new set of arguments. You can instruct the
1777 wrapper to refuse to link against libraries not in the store by setting the
1778 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
1780 @node Upgrading Guix
1781 @section Upgrading Guix
1783 @cindex Upgrading Guix, on a foreign distro
1785 To upgrade Guix, run:
1791 @xref{Invoking guix pull}, for more information.
1793 @cindex upgrading Guix for the root user, on a foreign distro
1794 @cindex upgrading the Guix daemon, on a foreign distro
1795 @cindex @command{guix pull} for the root user, on a foreign distro
1797 On a foreign distro, you can upgrade the build daemon by running:
1804 followed by (assuming your distro uses the systemd service management
1808 systemctl restart guix-daemon.service
1811 On Guix System, upgrading the daemon is achieved by reconfiguring the
1812 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1816 @c *********************************************************************
1817 @node System Installation
1818 @chapter System Installation
1820 @cindex installing Guix System
1821 @cindex Guix System, installation
1822 This section explains how to install Guix System
1823 on a machine. Guix, as a package manager, can
1824 also be installed on top of a running GNU/Linux system,
1825 @pxref{Installation}.
1829 @c This paragraph is for people reading this from tty2 of the
1830 @c installation image.
1831 You are reading this documentation with an Info reader. For details on
1832 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1833 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1834 Info}. Hit @kbd{l} afterwards to come back here.
1836 Alternately, run @command{info info} in another tty to keep the manual
1842 * Limitations:: What you can expect.
1843 * Hardware Considerations:: Supported hardware.
1844 * USB Stick and DVD Installation:: Preparing the installation medium.
1845 * Preparing for Installation:: Networking, partitioning, etc.
1846 * Guided Graphical Installation:: Easy graphical installation.
1847 * Manual Installation:: Manual installation for wizards.
1848 * After System Installation:: When installation succeeded.
1849 * Installing Guix in a VM:: Guix System playground.
1850 * Building the Installation Image:: How this comes to be.
1854 @section Limitations
1856 We consider Guix System to be ready for a wide range of ``desktop'' and server
1857 use cases. The reliability guarantees it provides---transactional upgrades
1858 and rollbacks, reproducibility---make it a solid foundation.
1860 Nevertheless, before you proceed with the installation, be aware of the
1861 following noteworthy limitations applicable to version @value{VERSION}:
1865 Support for the Logical Volume Manager (LVM) is missing.
1868 More and more system services are provided (@pxref{Services}), but some
1872 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1873 as well as a number of X11 window managers. However, KDE is currently
1877 More than a disclaimer, this is an invitation to report issues (and success
1878 stories!), and to join us in improving it. @xref{Contributing}, for more
1882 @node Hardware Considerations
1883 @section Hardware Considerations
1885 @cindex hardware support on Guix System
1886 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1887 builds around the kernel Linux-libre, which means that only hardware for
1888 which free software drivers and firmware exist is supported. Nowadays,
1889 a wide range of off-the-shelf hardware is supported on
1890 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1891 Ethernet controllers. Unfortunately, there are still areas where
1892 hardware vendors deny users control over their own computing, and such
1893 hardware is not supported on Guix System.
1895 @cindex WiFi, hardware support
1896 One of the main areas where free drivers or firmware are lacking is WiFi
1897 devices. WiFi devices known to work include those using Atheros chips
1898 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1899 driver, and those using Broadcom/AirForce chips (BCM43xx with
1900 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1901 Linux-libre driver. Free firmware exists for both and is available
1902 out-of-the-box on Guix System, as part of @code{%base-firmware}
1903 (@pxref{operating-system Reference, @code{firmware}}).
1905 @cindex RYF, Respects Your Freedom
1906 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1907 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1908 certification program for hardware products that respect your freedom
1909 and your privacy and ensure that you have control over your device. We
1910 encourage you to check the list of RYF-certified devices.
1912 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1913 web site. It contains a catalog of hardware devices with information
1914 about their support in GNU/Linux.
1917 @node USB Stick and DVD Installation
1918 @section USB Stick and DVD Installation
1920 An ISO-9660 installation image that can be written to a USB stick or
1921 burnt to a DVD can be downloaded from
1922 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1923 where @var{system} is one of:
1927 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1930 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1933 @c start duplication of authentication part from ``Binary Installation''
1934 Make sure to download the associated @file{.sig} file and to verify the
1935 authenticity of the image against it, along these lines:
1938 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1939 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1942 If that command fails because you do not have the required public key,
1943 then run this command to import it:
1946 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1947 -qO - | gpg --import -
1951 and rerun the @code{gpg --verify} command.
1953 Take note that a warning like ``This key is not certified with a trusted
1954 signature!'' is normal.
1958 This image contains the tools necessary for an installation.
1959 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1961 @unnumberedsubsec Copying to a USB Stick
1963 To copy the image to a USB stick, follow these steps:
1967 Decompress the image using the @command{xz} command:
1970 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1974 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1975 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1976 copy the image with:
1979 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1983 Access to @file{/dev/sdX} usually requires root privileges.
1986 @unnumberedsubsec Burning on a DVD
1988 To copy the image to a DVD, follow these steps:
1992 Decompress the image using the @command{xz} command:
1995 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1999 Insert a blank DVD into your machine, and determine
2000 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2001 copy the image with:
2004 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
2007 Access to @file{/dev/srX} usually requires root privileges.
2010 @unnumberedsubsec Booting
2012 Once this is done, you should be able to reboot the system and boot from
2013 the USB stick or DVD. The latter usually requires you to get in the
2014 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2015 In order to boot from Libreboot, switch to the command mode by pressing
2016 the @kbd{c} key and type @command{search_grub usb}.
2018 @xref{Installing Guix in a VM}, if, instead, you would like to install
2019 Guix System in a virtual machine (VM).
2022 @node Preparing for Installation
2023 @section Preparing for Installation
2025 Once you have booted, you can use the guided graphical installer, which makes
2026 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
2027 if you are already familiar with GNU/Linux and if you want more control than
2028 what the graphical installer provides, you can choose the ``manual''
2029 installation process (@pxref{Manual Installation}).
2031 The graphical installer is available on TTY1. You can obtain root shells on
2032 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2033 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2034 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2035 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2036 which allows you to select text with the left mouse button and to paste it
2037 with the middle button.
2040 Installation requires access to the Internet so that any missing
2041 dependencies of your system configuration can be downloaded. See the
2042 ``Networking'' section below.
2045 @node Guided Graphical Installation
2046 @section Guided Graphical Installation
2048 The graphical installer is a text-based user interface. It will guide you,
2049 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2051 The first dialog boxes allow you to set up the system as you use it during the
2052 installation: you can choose the language, keyboard layout, and set up
2053 networking, which will be used during the installation. The image below shows
2054 the networking dialog.
2056 @image{images/installer-network,5in,, networking setup with the graphical installer}
2058 Later steps allow you to partition your hard disk, as shown in the image
2059 below, to choose whether or not to use encrypted file systems, to enter the
2060 host name and root password, and to create an additional account, among other
2063 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2065 Note that, at any time, the installer allows you to exit the current
2066 installation step and resume at a previous step, as show in the image below.
2068 @image{images/installer-resume,5in,, resuming the installation process}
2070 Once you're done, the installer produces an operating system configuration and
2071 displays it (@pxref{Using the Configuration System}). At that point you can
2072 hit ``OK'' and installation will proceed. On success, you can reboot into the
2073 new system and enjoy. @xref{After System Installation}, for what's next!
2076 @node Manual Installation
2077 @section Manual Installation
2079 This section describes how you would ``manually'' install GNU@tie{}Guix System
2080 on your machine. This option requires familiarity with GNU/Linux, with the
2081 shell, and with common administration tools. If you think this is not for
2082 you, consider using the guided graphical installer (@pxref{Guided Graphical
2085 The installation system provides root shells on TTYs 3 to 6; press
2086 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2087 many common tools needed to install the system. But it is also a full-blown
2088 Guix System, which means that you can install additional packages, should you
2089 need it, using @command{guix package} (@pxref{Invoking guix package}).
2092 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2093 * Proceeding with the Installation:: Installing.
2096 @node Keyboard Layout and Networking and Partitioning
2097 @subsection Keyboard Layout, Networking, and Partitioning
2099 Before you can install the system, you may want to adjust the keyboard layout,
2100 set up networking, and partition your target hard disk. This section will
2101 guide you through this.
2103 @subsubsection Keyboard Layout
2105 @cindex keyboard layout
2106 The installation image uses the US qwerty keyboard layout. If you want
2107 to change it, you can use the @command{loadkeys} command. For example,
2108 the following command selects the Dvorak keyboard layout:
2114 See the files under @file{/run/current-system/profile/share/keymaps} for
2115 a list of available keyboard layouts. Run @command{man loadkeys} for
2118 @subsubsection Networking
2120 Run the following command to see what your network interfaces are called:
2127 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2133 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2134 Wired interfaces have a name starting with @samp{e}; for example, the
2135 interface corresponding to the first on-board Ethernet controller is
2136 called @samp{eno1}. Wireless interfaces have a name starting with
2137 @samp{w}, like @samp{w1p2s0}.
2140 @item Wired connection
2141 To configure a wired network run the following command, substituting
2142 @var{interface} with the name of the wired interface you want to use.
2145 ifconfig @var{interface} up
2149 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2152 ip link set @var{interface} up
2155 @item Wireless connection
2158 To configure wireless networking, you can create a configuration file
2159 for the @command{wpa_supplicant} configuration tool (its location is not
2160 important) using one of the available text editors such as
2164 nano wpa_supplicant.conf
2167 As an example, the following stanza can go to this file and will work
2168 for many wireless networks, provided you give the actual SSID and
2169 passphrase for the network you are connecting to:
2173 ssid="@var{my-ssid}"
2175 psk="the network's secret passphrase"
2179 Start the wireless service and run it in the background with the
2180 following command (substitute @var{interface} with the name of the
2181 network interface you want to use):
2184 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2187 Run @command{man wpa_supplicant} for more information.
2191 At this point, you need to acquire an IP address. On a network where IP
2192 addresses are automatically assigned @i{via} DHCP, you can run:
2195 dhclient -v @var{interface}
2198 Try to ping a server to see if networking is up and running:
2204 Setting up network access is almost always a requirement because the
2205 image does not contain all the software and tools that may be needed.
2207 @cindex proxy, during system installation
2208 If you need HTTP and HTTPS access to go through a proxy, run the
2212 herd set-http-proxy guix-daemon @var{URL}
2216 where @var{URL} is the proxy URL, for example
2217 @code{http://example.org:8118}.
2219 @cindex installing over SSH
2220 If you want to, you can continue the installation remotely by starting
2224 herd start ssh-daemon
2227 Make sure to either set a password with @command{passwd}, or configure
2228 OpenSSH public key authentication before logging in.
2230 @subsubsection Disk Partitioning
2232 Unless this has already been done, the next step is to partition, and
2233 then format the target partition(s).
2235 The installation image includes several partitioning tools, including
2236 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2237 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2238 the partition layout you want:
2244 If your disk uses the GUID Partition Table (GPT) format and you plan to
2245 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2246 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2249 @cindex EFI, installation
2250 @cindex UEFI, installation
2251 @cindex ESP, EFI system partition
2252 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2253 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2254 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2257 parted /dev/sda set 1 esp on
2261 @vindex grub-bootloader
2262 @vindex grub-efi-bootloader
2263 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2264 @file{/sys/firmware/efi} exists in the installation image, then you should
2265 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2266 Otherwise you should use the BIOS-based GRUB, known as
2267 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2271 Once you are done partitioning the target hard disk drive, you have to
2272 create a file system on the relevant partition(s)@footnote{Currently
2273 Guix System only supports ext4, btrfs, and JFS file systems. In particular,
2274 code that reads file system UUIDs and labels only works for these file system
2275 types.}. For the ESP, if you have one and assuming it is
2276 @file{/dev/sda1}, run:
2279 mkfs.fat -F32 /dev/sda1
2282 Preferably, assign file systems a label so that you can easily and
2283 reliably refer to them in @code{file-system} declarations (@pxref{File
2284 Systems}). This is typically done using the @code{-L} option of
2285 @command{mkfs.ext4} and related commands. So, assuming the target root
2286 partition lives at @file{/dev/sda2}, a file system with the label
2287 @code{my-root} can be created with:
2290 mkfs.ext4 -L my-root /dev/sda2
2293 @cindex encrypted disk
2294 If you are instead planning to encrypt the root partition, you can use
2295 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2296 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2297 @code{man cryptsetup}} for more information.) Assuming you want to
2298 store the root partition on @file{/dev/sda2}, the command sequence would
2299 be along these lines:
2302 cryptsetup luksFormat /dev/sda2
2303 cryptsetup open --type luks /dev/sda2 my-partition
2304 mkfs.ext4 -L my-root /dev/mapper/my-partition
2307 Once that is done, mount the target file system under @file{/mnt}
2308 with a command like (again, assuming @code{my-root} is the label of the
2312 mount LABEL=my-root /mnt
2315 Also mount any other file systems you would like to use on the target
2316 system relative to this path. If you have opted for @file{/boot/efi} as an
2317 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2318 found by @code{guix system init} afterwards.
2320 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2321 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2322 sure to initialize them with @command{mkswap}. Assuming you have one
2323 swap partition on @file{/dev/sda3}, you would run:
2330 Alternatively, you may use a swap file. For example, assuming that in
2331 the new system you want to use the file @file{/swapfile} as a swap file,
2332 you would run@footnote{This example will work for many types of file
2333 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2334 btrfs), the required steps may be different. For details, see the
2335 manual pages for @command{mkswap} and @command{swapon}.}:
2338 # This is 10 GiB of swap space. Adjust "count" to change the size.
2339 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2340 # For security, make the file readable and writable only by root.
2341 chmod 600 /mnt/swapfile
2342 mkswap /mnt/swapfile
2343 swapon /mnt/swapfile
2346 Note that if you have encrypted the root partition and created a swap
2347 file in its file system as described above, then the encryption also
2348 protects the swap file, just like any other file in that file system.
2350 @node Proceeding with the Installation
2351 @subsection Proceeding with the Installation
2353 With the target partitions ready and the target root mounted on
2354 @file{/mnt}, we're ready to go. First, run:
2357 herd start cow-store /mnt
2360 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2361 during the installation phase are written to the target disk on @file{/mnt}
2362 rather than kept in memory. This is necessary because the first phase of
2363 the @command{guix system init} command (see below) entails downloads or
2364 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2366 Next, you have to edit a file and
2367 provide the declaration of the operating system to be installed. To
2368 that end, the installation system comes with three text editors. We
2369 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2370 supports syntax highlighting and parentheses matching; other editors
2371 include GNU Zile (an Emacs clone), and
2372 nvi (a clone of the original BSD @command{vi} editor).
2373 We strongly recommend storing that file on the target root file system, say,
2374 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2375 configuration file once you have rebooted into the newly-installed system.
2377 @xref{Using the Configuration System}, for an overview of the
2378 configuration file. The example configurations discussed in that
2379 section are available under @file{/etc/configuration} in the
2380 installation image. Thus, to get started with a system configuration
2381 providing a graphical display server (a ``desktop'' system), you can run
2382 something along these lines:
2386 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2387 # nano /mnt/etc/config.scm
2390 You should pay attention to what your configuration file contains, and
2395 Make sure the @code{bootloader-configuration} form refers to the target
2396 you want to install GRUB on. It should mention @code{grub-bootloader} if
2397 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2398 for newer UEFI systems. For legacy systems, the @code{target} field
2399 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2400 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2401 currently mounted and a @code{file-system} entry is specified in your
2405 Be sure that your file system labels match the value of their respective
2406 @code{device} fields in your @code{file-system} configuration, assuming
2407 your @code{file-system} configuration uses the @code{file-system-label}
2408 procedure in its @code{device} field.
2411 If there are encrypted or RAID partitions, make sure to add a
2412 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2415 Once you are done preparing the configuration file, the new system must
2416 be initialized (remember that the target root file system is mounted
2420 guix system init /mnt/etc/config.scm /mnt
2424 This copies all the necessary files and installs GRUB on
2425 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2426 more information, @pxref{Invoking guix system}. This command may trigger
2427 downloads or builds of missing packages, which can take some time.
2429 Once that command has completed---and hopefully succeeded!---you can run
2430 @command{reboot} and boot into the new system. The @code{root} password
2431 in the new system is initially empty; other users' passwords need to be
2432 initialized by running the @command{passwd} command as @code{root},
2433 unless your configuration specifies otherwise
2434 (@pxref{user-account-password, user account passwords}).
2435 @xref{After System Installation}, for what's next!
2438 @node After System Installation
2439 @section After System Installation
2441 Success, you've now booted into Guix System! From then on, you can update the
2442 system whenever you want by running, say:
2446 sudo guix system reconfigure /etc/config.scm
2450 This builds a new system generation with the latest packages and services
2451 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2452 your system includes the latest security updates (@pxref{Security Updates}).
2454 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2456 @cindex sudo vs. @command{guix pull}
2457 Note that @command{sudo guix} runs your user's @command{guix} command and
2458 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2459 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2461 The difference matters here, because @command{guix pull} updates
2462 the @command{guix} command and package definitions only for the user it is ran
2463 as. This means that if you choose to use @command{guix system reconfigure} in
2464 root's login shell, you'll need to @command{guix pull} separately.
2467 Join us on @code{#guix} on the Freenode IRC network or on
2468 @email{guix-devel@@gnu.org} to share your experience!
2471 @node Installing Guix in a VM
2472 @section Installing Guix in a Virtual Machine
2474 @cindex virtual machine, Guix System installation
2475 @cindex virtual private server (VPS)
2476 @cindex VPS (virtual private server)
2477 If you'd like to install Guix System in a virtual machine (VM) or on a
2478 virtual private server (VPS) rather than on your beloved machine, this
2481 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2482 disk image, follow these steps:
2486 First, retrieve and decompress the Guix system installation image as
2487 described previously (@pxref{USB Stick and DVD Installation}).
2490 Create a disk image that will hold the installed system. To make a
2491 qcow2-formatted disk image, use the @command{qemu-img} command:
2494 qemu-img create -f qcow2 guix-system.img 50G
2497 The resulting file will be much smaller than 50 GB (typically less than
2498 1 MB), but it will grow as the virtualized storage device is filled up.
2501 Boot the USB installation image in an VM:
2504 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2505 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2506 -drive file=guix-system.img \
2507 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2510 @code{-enable-kvm} is optional, but significantly improves performance,
2511 @pxref{Running Guix in a VM}.
2514 You're now root in the VM, proceed with the installation process.
2515 @xref{Preparing for Installation}, and follow the instructions.
2518 Once installation is complete, you can boot the system that's on your
2519 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2522 @node Building the Installation Image
2523 @section Building the Installation Image
2525 @cindex installation image
2526 The installation image described above was built using the @command{guix
2527 system} command, specifically:
2530 guix system disk-image --file-system-type=iso9660 \
2531 gnu/system/install.scm
2534 Have a look at @file{gnu/system/install.scm} in the source tree,
2535 and see also @ref{Invoking guix system} for more information
2536 about the installation image.
2538 @section Building the Installation Image for ARM Boards
2540 Many ARM boards require a specific variant of the
2541 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2543 If you build a disk image and the bootloader is not available otherwise
2544 (on another boot drive etc), it's advisable to build an image that
2545 includes the bootloader, specifically:
2548 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2551 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2552 board, a list of possible boards will be printed.
2554 @c *********************************************************************
2555 @node Package Management
2556 @chapter Package Management
2559 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2560 remove software packages, without having to know about their build
2561 procedures or dependencies. Guix also goes beyond this obvious set of
2564 This chapter describes the main features of Guix, as well as the
2565 package management tools it provides. Along with the command-line
2566 interface described below (@pxref{Invoking guix package, @code{guix
2567 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2568 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2569 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2573 guix install emacs-guix
2577 * Features:: How Guix will make your life brighter.
2578 * Invoking guix package:: Package installation, removal, etc.
2579 * Substitutes:: Downloading pre-built binaries.
2580 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2581 * Invoking guix gc:: Running the garbage collector.
2582 * Invoking guix pull:: Fetching the latest Guix and distribution.
2583 * Channels:: Customizing the package collection.
2584 * Invoking guix time-machine:: Running an older revision of Guix.
2585 * Inferiors:: Interacting with another revision of Guix.
2586 * Invoking guix describe:: Display information about your Guix revision.
2587 * Invoking guix archive:: Exporting and importing store files.
2593 When using Guix, each package ends up in the @dfn{package store}, in its
2594 own directory---something that resembles
2595 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2597 Instead of referring to these directories, users have their own
2598 @dfn{profile}, which points to the packages that they actually want to
2599 use. These profiles are stored within each user's home directory, at
2600 @code{$HOME/.guix-profile}.
2602 For example, @code{alice} installs GCC 4.7.2. As a result,
2603 @file{/home/alice/.guix-profile/bin/gcc} points to
2604 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2605 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2606 simply continues to point to
2607 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2608 coexist on the same system without any interference.
2610 The @command{guix package} command is the central tool to manage
2611 packages (@pxref{Invoking guix package}). It operates on the per-user
2612 profiles, and can be used @emph{with normal user privileges}.
2614 @cindex transactions
2615 The command provides the obvious install, remove, and upgrade
2616 operations. Each invocation is actually a @emph{transaction}: either
2617 the specified operation succeeds, or nothing happens. Thus, if the
2618 @command{guix package} process is terminated during the transaction,
2619 or if a power outage occurs during the transaction, then the user's
2620 profile remains in its previous state, and remains usable.
2622 In addition, any package transaction may be @emph{rolled back}. So, if,
2623 for example, an upgrade installs a new version of a package that turns
2624 out to have a serious bug, users may roll back to the previous instance
2625 of their profile, which was known to work well. Similarly, the global
2626 system configuration on Guix is subject to
2627 transactional upgrades and roll-back
2628 (@pxref{Using the Configuration System}).
2630 All packages in the package store may be @emph{garbage-collected}.
2631 Guix can determine which packages are still referenced by user
2632 profiles, and remove those that are provably no longer referenced
2633 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2634 generations of their profile so that the packages they refer to can be
2637 @cindex reproducibility
2638 @cindex reproducible builds
2639 Guix takes a @dfn{purely functional} approach to package
2640 management, as described in the introduction (@pxref{Introduction}).
2641 Each @file{/gnu/store} package directory name contains a hash of all the
2642 inputs that were used to build that package---compiler, libraries, build
2643 scripts, etc. This direct correspondence allows users to make sure a
2644 given package installation matches the current state of their
2645 distribution. It also helps maximize @dfn{build reproducibility}:
2646 thanks to the isolated build environments that are used, a given build
2647 is likely to yield bit-identical files when performed on different
2648 machines (@pxref{Invoking guix-daemon, container}).
2651 This foundation allows Guix to support @dfn{transparent binary/source
2652 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2653 available from an external source---a @dfn{substitute}, Guix just
2654 downloads it and unpacks it;
2655 otherwise, it builds the package from source, locally
2656 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2657 reproducible, users do not have to trust servers that provide
2658 substitutes: they can force a local build and @emph{challenge} providers
2659 (@pxref{Invoking guix challenge}).
2661 Control over the build environment is a feature that is also useful for
2662 developers. The @command{guix environment} command allows developers of
2663 a package to quickly set up the right development environment for their
2664 package, without having to manually install the dependencies of the
2665 package into their profile (@pxref{Invoking guix environment}).
2667 @cindex replication, of software environments
2668 @cindex provenance tracking, of software artifacts
2669 All of Guix and its package definitions is version-controlled, and
2670 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2671 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2672 Guix instance on a different machine or at a later point in time, which in
2673 turn allows you to @emph{replicate complete software environments}, while
2674 retaining precise @dfn{provenance tracking} of the software.
2676 @node Invoking guix package
2677 @section Invoking @command{guix package}
2679 @cindex installing packages
2680 @cindex removing packages
2681 @cindex package installation
2682 @cindex package removal
2683 The @command{guix package} command is the tool that allows users to
2684 install, upgrade, and remove packages, as well as rolling back to
2685 previous configurations. It operates only on the user's own profile,
2686 and works with normal user privileges (@pxref{Features}). Its syntax
2690 guix package @var{options}
2693 @cindex transactions
2694 Primarily, @var{options} specifies the operations to be performed during
2695 the transaction. Upon completion, a new profile is created, but
2696 previous @dfn{generations} of the profile remain available, should the user
2699 For example, to remove @code{lua} and install @code{guile} and
2700 @code{guile-cairo} in a single transaction:
2703 guix package -r lua -i guile guile-cairo
2706 @cindex aliases, for @command{guix package}
2707 For your convenience, we also provide the following aliases:
2711 @command{guix search} is an alias for @command{guix package -s},
2713 @command{guix install} is an alias for @command{guix package -i},
2715 @command{guix remove} is an alias for @command{guix package -r},
2717 @command{guix upgrade} is an alias for @command{guix package -u},
2719 and @command{guix show} is an alias for @command{guix package --show=}.
2722 These aliases are less expressive than @command{guix package} and provide
2723 fewer options, so in some cases you'll probably want to use @command{guix
2726 @command{guix package} also supports a @dfn{declarative approach}
2727 whereby the user specifies the exact set of packages to be available and
2728 passes it @i{via} the @option{--manifest} option
2729 (@pxref{profile-manifest, @option{--manifest}}).
2732 For each user, a symlink to the user's default profile is automatically
2733 created in @file{$HOME/.guix-profile}. This symlink always points to the
2734 current generation of the user's default profile. Thus, users can add
2735 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2736 variable, and so on.
2737 @cindex search paths
2738 If you are not using Guix System, consider adding the
2739 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2740 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2741 shells get all the right environment variable definitions:
2744 GUIX_PROFILE="$HOME/.guix-profile" ; \
2745 source "$HOME/.guix-profile/etc/profile"
2748 In a multi-user setup, user profiles are stored in a place registered as
2749 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2750 to (@pxref{Invoking guix gc}). That directory is normally
2751 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2752 @var{localstatedir} is the value passed to @code{configure} as
2753 @code{--localstatedir}, and @var{user} is the user name. The
2754 @file{per-user} directory is created when @command{guix-daemon} is
2755 started, and the @var{user} sub-directory is created by @command{guix
2758 The @var{options} can be among the following:
2762 @item --install=@var{package} @dots{}
2763 @itemx -i @var{package} @dots{}
2764 Install the specified @var{package}s.
2766 Each @var{package} may specify either a simple package name, such as
2767 @code{guile}, or a package name followed by an at-sign and version number,
2768 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2769 case, the newest version prefixed by @code{1.8} is selected.)
2771 If no version number is specified, the
2772 newest available version will be selected. In addition, @var{package}
2773 may contain a colon, followed by the name of one of the outputs of the
2774 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2775 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2776 name (and optionally version) are searched for among the GNU
2777 distribution modules (@pxref{Package Modules}).
2779 @cindex propagated inputs
2780 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2781 that automatically get installed along with the required package
2782 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2783 @code{package} objects}, for information about propagated inputs in
2784 package definitions).
2786 @anchor{package-cmd-propagated-inputs}
2787 An example is the GNU MPC library: its C header files refer to those of
2788 the GNU MPFR library, which in turn refer to those of the GMP library.
2789 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2790 in the profile; removing MPC also removes MPFR and GMP---unless they had
2791 also been explicitly installed by the user.
2793 Besides, packages sometimes rely on the definition of environment
2794 variables for their search paths (see explanation of
2795 @code{--search-paths} below). Any missing or possibly incorrect
2796 environment variable definitions are reported here.
2798 @item --install-from-expression=@var{exp}
2800 Install the package @var{exp} evaluates to.
2802 @var{exp} must be a Scheme expression that evaluates to a
2803 @code{<package>} object. This option is notably useful to disambiguate
2804 between same-named variants of a package, with expressions such as
2805 @code{(@@ (gnu packages base) guile-final)}.
2807 Note that this option installs the first output of the specified
2808 package, which may be insufficient when needing a specific output of a
2809 multiple-output package.
2811 @item --install-from-file=@var{file}
2812 @itemx -f @var{file}
2813 Install the package that the code within @var{file} evaluates to.
2815 As an example, @var{file} might contain a definition like this
2816 (@pxref{Defining Packages}):
2819 @include package-hello.scm
2822 Developers may find it useful to include such a @file{guix.scm} file
2823 in the root of their project source tree that can be used to test
2824 development snapshots and create reproducible development environments
2825 (@pxref{Invoking guix environment}).
2827 The @var{file} may also contain a JSON representation of one or more
2828 package definitions. Running @code{guix package -f} on
2829 @file{hello.json} with the following contents would result in installing
2830 the package @code{greeter} after building @code{myhello}:
2833 @verbatiminclude package-hello.json
2836 @item --remove=@var{package} @dots{}
2837 @itemx -r @var{package} @dots{}
2838 Remove the specified @var{package}s.
2840 As for @code{--install}, each @var{package} may specify a version number
2841 and/or output name in addition to the package name. For instance,
2842 @code{-r glibc:debug} would remove the @code{debug} output of
2845 @item --upgrade[=@var{regexp} @dots{}]
2846 @itemx -u [@var{regexp} @dots{}]
2847 @cindex upgrading packages
2848 Upgrade all the installed packages. If one or more @var{regexp}s are
2849 specified, upgrade only installed packages whose name matches a
2850 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2852 Note that this upgrades package to the latest version of packages found
2853 in the distribution currently installed. To update your distribution,
2854 you should regularly run @command{guix pull} (@pxref{Invoking guix
2857 @item --do-not-upgrade[=@var{regexp} @dots{}]
2858 When used together with the @code{--upgrade} option, do @emph{not}
2859 upgrade any packages whose name matches a @var{regexp}. For example, to
2860 upgrade all packages in the current profile except those containing the
2861 substring ``emacs'':
2864 $ guix package --upgrade . --do-not-upgrade emacs
2867 @item @anchor{profile-manifest}--manifest=@var{file}
2868 @itemx -m @var{file}
2869 @cindex profile declaration
2870 @cindex profile manifest
2871 Create a new generation of the profile from the manifest object
2872 returned by the Scheme code in @var{file}. This option can be repeated
2873 several times, in which case the manifests are concatenated.
2875 This allows you to @emph{declare} the profile's contents rather than
2876 constructing it through a sequence of @code{--install} and similar
2877 commands. The advantage is that @var{file} can be put under version
2878 control, copied to different machines to reproduce the same profile, and
2881 @c FIXME: Add reference to (guix profile) documentation when available.
2882 @var{file} must return a @dfn{manifest} object, which is roughly a list
2885 @findex packages->manifest
2887 (use-package-modules guile emacs)
2892 ;; Use a specific package output.
2893 (list guile-2.0 "debug")))
2896 @findex specifications->manifest
2897 In this example we have to know which modules define the @code{emacs}
2898 and @code{guile-2.0} variables to provide the right
2899 @code{use-package-modules} line, which can be cumbersome. We can
2900 instead provide regular package specifications and let
2901 @code{specifications->manifest} look up the corresponding package
2905 (specifications->manifest
2906 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2910 @cindex rolling back
2911 @cindex undoing transactions
2912 @cindex transactions, undoing
2913 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2914 the last transaction.
2916 When combined with options such as @code{--install}, roll back occurs
2917 before any other actions.
2919 When rolling back from the first generation that actually contains
2920 installed packages, the profile is made to point to the @dfn{zeroth
2921 generation}, which contains no files apart from its own metadata.
2923 After having rolled back, installing, removing, or upgrading packages
2924 overwrites previous future generations. Thus, the history of the
2925 generations in a profile is always linear.
2927 @item --switch-generation=@var{pattern}
2928 @itemx -S @var{pattern}
2930 Switch to a particular generation defined by @var{pattern}.
2932 @var{pattern} may be either a generation number or a number prefixed
2933 with ``+'' or ``-''. The latter means: move forward/backward by a
2934 specified number of generations. For example, if you want to return to
2935 the latest generation after @code{--roll-back}, use
2936 @code{--switch-generation=+1}.
2938 The difference between @code{--roll-back} and
2939 @code{--switch-generation=-1} is that @code{--switch-generation} will
2940 not make a zeroth generation, so if a specified generation does not
2941 exist, the current generation will not be changed.
2943 @item --search-paths[=@var{kind}]
2944 @cindex search paths
2945 Report environment variable definitions, in Bash syntax, that may be
2946 needed in order to use the set of installed packages. These environment
2947 variables are used to specify @dfn{search paths} for files used by some
2948 of the installed packages.
2950 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2951 environment variables to be defined so it can look for headers and
2952 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2953 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2954 library are installed in the profile, then @code{--search-paths} will
2955 suggest setting these variables to @code{@var{profile}/include} and
2956 @code{@var{profile}/lib}, respectively.
2958 The typical use case is to define these environment variables in the
2962 $ eval `guix package --search-paths`
2965 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2966 meaning that the returned environment variable definitions will either
2967 be exact settings, or prefixes or suffixes of the current value of these
2968 variables. When omitted, @var{kind} defaults to @code{exact}.
2970 This option can also be used to compute the @emph{combined} search paths
2971 of several profiles. Consider this example:
2974 $ guix package -p foo -i guile
2975 $ guix package -p bar -i guile-json
2976 $ guix package -p foo -p bar --search-paths
2979 The last command above reports about the @code{GUILE_LOAD_PATH}
2980 variable, even though, taken individually, neither @file{foo} nor
2981 @file{bar} would lead to that recommendation.
2984 @item --profile=@var{profile}
2985 @itemx -p @var{profile}
2986 Use @var{profile} instead of the user's default profile.
2988 @var{profile} must be the name of a file that will be created upon
2989 completion. Concretely, @var{profile} will be a mere symbolic link
2990 (``symlink'') pointing to the actual profile where packages are
2994 $ guix install hello -p ~/code/my-profile
2996 $ ~/code/my-profile/bin/hello
3000 All it takes to get rid of the profile is to remove this symlink and its
3001 siblings that point to specific generations:
3004 $ rm ~/code/my-profile ~/code/my-profile-*-link
3007 @item --list-profiles
3008 List all the user's profiles:
3011 $ guix package --list-profiles
3012 /home/charlie/.guix-profile
3013 /home/charlie/code/my-profile
3014 /home/charlie/code/devel-profile
3015 /home/charlie/tmp/test
3018 When running as root, list all the profiles of all the users.
3020 @cindex collisions, in a profile
3021 @cindex colliding packages in profiles
3022 @cindex profile collisions
3023 @item --allow-collisions
3024 Allow colliding packages in the new profile. Use at your own risk!
3026 By default, @command{guix package} reports as an error @dfn{collisions}
3027 in the profile. Collisions happen when two or more different versions
3028 or variants of a given package end up in the profile.
3031 Use the bootstrap Guile to build the profile. This option is only
3032 useful to distribution developers.
3036 In addition to these actions, @command{guix package} supports the
3037 following options to query the current state of a profile, or the
3038 availability of packages:
3042 @item --search=@var{regexp}
3043 @itemx -s @var{regexp}
3044 @cindex searching for packages
3045 List the available packages whose name, synopsis, or description matches
3046 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3047 Print all the metadata of matching packages in
3048 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3049 GNU recutils manual}).
3051 This allows specific fields to be extracted using the @command{recsel}
3052 command, for instance:
3055 $ guix package -s malloc | recsel -p name,version,relevance
3069 Similarly, to show the name of all the packages available under the
3070 terms of the GNU@tie{}LGPL version 3:
3073 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3080 It is also possible to refine search results using several @code{-s} flags to
3081 @command{guix package}, or several arguments to @command{guix search}. For
3082 example, the following command returns a list of board games (this time using
3083 the @command{guix search} alias):
3086 $ guix search '\<board\>' game | recsel -p name
3091 If we were to omit @code{-s game}, we would also get software packages
3092 that deal with printed circuit boards; removing the angle brackets
3093 around @code{board} would further add packages that have to do with
3096 And now for a more elaborate example. The following command searches
3097 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3098 libraries, and prints the name and synopsis of the matching packages:
3101 $ guix search crypto library | \
3102 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3106 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3107 information on @dfn{selection expressions} for @code{recsel -e}.
3109 @item --show=@var{package}
3110 Show details about @var{package}, taken from the list of available packages, in
3111 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3115 $ guix package --show=python | recsel -p name,version
3123 You may also specify the full name of a package to only get details about a
3124 specific version of it (this time using the @command{guix show} alias):
3126 $ guix show python@@3.4 | recsel -p name,version
3133 @item --list-installed[=@var{regexp}]
3134 @itemx -I [@var{regexp}]
3135 List the currently installed packages in the specified profile, with the
3136 most recently installed packages shown last. When @var{regexp} is
3137 specified, list only installed packages whose name matches @var{regexp}.
3139 For each installed package, print the following items, separated by
3140 tabs: the package name, its version string, the part of the package that
3141 is installed (for instance, @code{out} for the default output,
3142 @code{include} for its headers, etc.), and the path of this package in
3145 @item --list-available[=@var{regexp}]
3146 @itemx -A [@var{regexp}]
3147 List packages currently available in the distribution for this system
3148 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3149 available packages whose name matches @var{regexp}.
3151 For each package, print the following items separated by tabs: its name,
3152 its version string, the parts of the package (@pxref{Packages with
3153 Multiple Outputs}), and the source location of its definition.
3155 @item --list-generations[=@var{pattern}]
3156 @itemx -l [@var{pattern}]
3158 Return a list of generations along with their creation dates; for each
3159 generation, show the installed packages, with the most recently
3160 installed packages shown last. Note that the zeroth generation is never
3163 For each installed package, print the following items, separated by
3164 tabs: the name of a package, its version string, the part of the package
3165 that is installed (@pxref{Packages with Multiple Outputs}), and the
3166 location of this package in the store.
3168 When @var{pattern} is used, the command returns only matching
3169 generations. Valid patterns include:
3172 @item @emph{Integers and comma-separated integers}. Both patterns denote
3173 generation numbers. For instance, @code{--list-generations=1} returns
3176 And @code{--list-generations=1,8,2} outputs three generations in the
3177 specified order. Neither spaces nor trailing commas are allowed.
3179 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3180 specified generations and everything in between. Note that the start of
3181 a range must be smaller than its end.
3183 It is also possible to omit the endpoint. For example,
3184 @code{--list-generations=2..}, returns all generations starting from the
3187 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3188 or months by passing an integer along with the first letter of the
3189 duration. For example, @code{--list-generations=20d} lists generations
3190 that are up to 20 days old.
3193 @item --delete-generations[=@var{pattern}]
3194 @itemx -d [@var{pattern}]
3195 When @var{pattern} is omitted, delete all generations except the current
3198 This command accepts the same patterns as @option{--list-generations}.
3199 When @var{pattern} is specified, delete the matching generations. When
3200 @var{pattern} specifies a duration, generations @emph{older} than the
3201 specified duration match. For instance, @code{--delete-generations=1m}
3202 deletes generations that are more than one month old.
3204 If the current generation matches, it is @emph{not} deleted. Also, the
3205 zeroth generation is never deleted.
3207 Note that deleting generations prevents rolling back to them.
3208 Consequently, this command must be used with care.
3212 Finally, since @command{guix package} may actually start build
3213 processes, it supports all the common build options (@pxref{Common Build
3214 Options}). It also supports package transformation options, such as
3215 @option{--with-source} (@pxref{Package Transformation Options}).
3216 However, note that package transformations are lost when upgrading; to
3217 preserve transformations across upgrades, you should define your own
3218 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3219 (@pxref{Defining Packages}).
3222 @section Substitutes
3225 @cindex pre-built binaries
3226 Guix supports transparent source/binary deployment, which means that it
3227 can either build things locally, or download pre-built items from a
3228 server, or both. We call these pre-built items @dfn{substitutes}---they
3229 are substitutes for local build results. In many cases, downloading a
3230 substitute is much faster than building things locally.
3232 Substitutes can be anything resulting from a derivation build
3233 (@pxref{Derivations}). Of course, in the common case, they are
3234 pre-built package binaries, but source tarballs, for instance, which
3235 also result from derivation builds, can be available as substitutes.
3238 * Official Substitute Server:: One particular source of substitutes.
3239 * Substitute Server Authorization:: How to enable or disable substitutes.
3240 * Substitute Authentication:: How Guix verifies substitutes.
3241 * Proxy Settings:: How to get substitutes via proxy.
3242 * Substitution Failure:: What happens when substitution fails.
3243 * On Trusting Binaries:: How can you trust that binary blob?
3246 @node Official Substitute Server
3247 @subsection Official Substitute Server
3250 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3251 that builds packages from Guix continuously for some
3252 architectures, and makes them available as substitutes. This is the
3253 default source of substitutes; it can be overridden by passing the
3254 @option{--substitute-urls} option either to @command{guix-daemon}
3255 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3256 or to client tools such as @command{guix package}
3257 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3260 Substitute URLs can be either HTTP or HTTPS.
3261 HTTPS is recommended because communications are encrypted; conversely,
3262 using HTTP makes all communications visible to an eavesdropper, who
3263 could use the information gathered to determine, for instance, whether
3264 your system has unpatched security vulnerabilities.
3266 Substitutes from the official build farm are enabled by default when
3267 using Guix System (@pxref{GNU Distribution}). However,
3268 they are disabled by default when using Guix on a foreign distribution,
3269 unless you have explicitly enabled them via one of the recommended
3270 installation steps (@pxref{Installation}). The following paragraphs
3271 describe how to enable or disable substitutes for the official build
3272 farm; the same procedure can also be used to enable substitutes for any
3273 other substitute server.
3275 @node Substitute Server Authorization
3276 @subsection Substitute Server Authorization
3279 @cindex substitutes, authorization thereof
3280 @cindex access control list (ACL), for substitutes
3281 @cindex ACL (access control list), for substitutes
3282 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3284 must add its public key to the access control list (ACL) of archive
3285 imports, using the @command{guix archive} command (@pxref{Invoking guix
3286 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3287 be compromised and to serve genuine substitutes.
3289 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3290 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3291 the installation prefix of Guix. If you installed Guix from source,
3292 make sure you checked the GPG signature of
3293 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3294 Then, you can run something like this:
3297 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3300 Once this is in place, the output of a command like @code{guix build}
3301 should change from something like:
3304 $ guix build emacs --dry-run
3305 The following derivations would be built:
3306 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3307 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3308 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3309 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3317 $ guix build emacs --dry-run
3318 112.3 MB would be downloaded:
3319 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3320 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3321 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3322 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3327 The text changed from ``The following derivations would be built'' to
3328 ``112.3 MB would be downloaded''. This indicates that substitutes from
3329 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3330 possible, for future builds.
3332 @cindex substitutes, how to disable
3333 The substitute mechanism can be disabled globally by running
3334 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3335 guix-daemon}). It can also be disabled temporarily by passing the
3336 @code{--no-substitutes} option to @command{guix package}, @command{guix
3337 build}, and other command-line tools.
3339 @node Substitute Authentication
3340 @subsection Substitute Authentication
3342 @cindex digital signatures
3343 Guix detects and raises an error when attempting to use a substitute
3344 that has been tampered with. Likewise, it ignores substitutes that are
3345 not signed, or that are not signed by one of the keys listed in the ACL.
3347 There is one exception though: if an unauthorized server provides
3348 substitutes that are @emph{bit-for-bit identical} to those provided by
3349 an authorized server, then the unauthorized server becomes eligible for
3350 downloads. For example, assume we have chosen two substitute servers
3354 --substitute-urls="https://a.example.org https://b.example.org"
3358 @cindex reproducible builds
3359 If the ACL contains only the key for @code{b.example.org}, and if
3360 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3361 then Guix will download substitutes from @code{a.example.org} because it
3362 comes first in the list and can be considered a mirror of
3363 @code{b.example.org}. In practice, independent build machines usually
3364 produce the same binaries, thanks to bit-reproducible builds (see
3367 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3368 (in other words, the server is not authenticated), contrary to what
3369 HTTPS clients such as Web browsers usually do. This is because Guix
3370 authenticates substitute information itself, as explained above, which
3371 is what we care about (whereas X.509 certificates are about
3372 authenticating bindings between domain names and public keys.)
3374 @node Proxy Settings
3375 @subsection Proxy Settings
3378 Substitutes are downloaded over HTTP or HTTPS.
3379 The @code{http_proxy} environment
3380 variable can be set in the environment of @command{guix-daemon} and is
3381 honored for downloads of substitutes. Note that the value of
3382 @code{http_proxy} in the environment where @command{guix build},
3383 @command{guix package}, and other client commands are run has
3384 @emph{absolutely no effect}.
3386 @node Substitution Failure
3387 @subsection Substitution Failure
3389 Even when a substitute for a derivation is available, sometimes the
3390 substitution attempt will fail. This can happen for a variety of
3391 reasons: the substitute server might be offline, the substitute may
3392 recently have been deleted, the connection might have been interrupted,
3395 When substitutes are enabled and a substitute for a derivation is
3396 available, but the substitution attempt fails, Guix will attempt to
3397 build the derivation locally depending on whether or not
3398 @code{--fallback} was given (@pxref{fallback-option,, common build
3399 option @code{--fallback}}). Specifically, if @code{--fallback} was
3400 omitted, then no local build will be performed, and the derivation is
3401 considered to have failed. However, if @code{--fallback} was given,
3402 then Guix will attempt to build the derivation locally, and the success
3403 or failure of the derivation depends on the success or failure of the
3404 local build. Note that when substitutes are disabled or no substitute
3405 is available for the derivation in question, a local build will
3406 @emph{always} be performed, regardless of whether or not
3407 @code{--fallback} was given.
3409 To get an idea of how many substitutes are available right now, you can
3410 try running the @command{guix weather} command (@pxref{Invoking guix
3411 weather}). This command provides statistics on the substitutes provided
3414 @node On Trusting Binaries
3415 @subsection On Trusting Binaries
3417 @cindex trust, of pre-built binaries
3418 Today, each individual's control over their own computing is at the
3419 mercy of institutions, corporations, and groups with enough power and
3420 determination to subvert the computing infrastructure and exploit its
3421 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3422 convenient, we encourage users to also build on their own, or even run
3423 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3424 interesting target. One way to help is by publishing the software you
3425 build using @command{guix publish} so that others have one more choice
3426 of server to download substitutes from (@pxref{Invoking guix publish}).
3428 Guix has the foundations to maximize build reproducibility
3429 (@pxref{Features}). In most cases, independent builds of a given
3430 package or derivation should yield bit-identical results. Thus, through
3431 a diverse set of independent package builds, we can strengthen the
3432 integrity of our systems. The @command{guix challenge} command aims to
3433 help users assess substitute servers, and to assist developers in
3434 finding out about non-deterministic package builds (@pxref{Invoking guix
3435 challenge}). Similarly, the @option{--check} option of @command{guix
3436 build} allows users to check whether previously-installed substitutes
3437 are genuine by rebuilding them locally (@pxref{build-check,
3438 @command{guix build --check}}).
3440 In the future, we want Guix to have support to publish and retrieve
3441 binaries to/from other users, in a peer-to-peer fashion. If you would
3442 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3444 @node Packages with Multiple Outputs
3445 @section Packages with Multiple Outputs
3447 @cindex multiple-output packages
3448 @cindex package outputs
3451 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3452 source package leads to exactly one directory in the store. When running
3453 @command{guix install glibc}, one installs the default output of the
3454 GNU libc package; the default output is called @code{out}, but its name
3455 can be omitted as shown in this command. In this particular case, the
3456 default output of @code{glibc} contains all the C header files, shared
3457 libraries, static libraries, Info documentation, and other supporting
3460 Sometimes it is more appropriate to separate the various types of files
3461 produced from a single source package into separate outputs. For
3462 instance, the GLib C library (used by GTK+ and related packages)
3463 installs more than 20 MiB of reference documentation as HTML pages.
3464 To save space for users who do not need it, the documentation goes to a
3465 separate output, called @code{doc}. To install the main GLib output,
3466 which contains everything but the documentation, one would run:
3472 @cindex documentation
3473 The command to install its documentation is:
3476 guix install glib:doc
3479 Some packages install programs with different ``dependency footprints''.
3480 For instance, the WordNet package installs both command-line tools and
3481 graphical user interfaces (GUIs). The former depend solely on the C
3482 library, whereas the latter depend on Tcl/Tk and the underlying X
3483 libraries. In this case, we leave the command-line tools in the default
3484 output, whereas the GUIs are in a separate output. This allows users
3485 who do not need the GUIs to save space. The @command{guix size} command
3486 can help find out about such situations (@pxref{Invoking guix size}).
3487 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3489 There are several such multiple-output packages in the GNU distribution.
3490 Other conventional output names include @code{lib} for libraries and
3491 possibly header files, @code{bin} for stand-alone programs, and
3492 @code{debug} for debugging information (@pxref{Installing Debugging
3493 Files}). The outputs of a packages are listed in the third column of
3494 the output of @command{guix package --list-available} (@pxref{Invoking
3498 @node Invoking guix gc
3499 @section Invoking @command{guix gc}
3501 @cindex garbage collector
3503 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3504 The @command{guix gc} command allows users to explicitly run the garbage
3505 collector to reclaim space from the @file{/gnu/store} directory. It is
3506 the @emph{only} way to remove files from @file{/gnu/store}---removing
3507 files or directories manually may break it beyond repair!
3510 @cindex garbage collector roots
3511 The garbage collector has a set of known @dfn{roots}: any file under
3512 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3513 cannot be deleted; any other file is considered @dfn{dead} and may be
3514 deleted. The set of garbage collector roots (``GC roots'' for short)
3515 includes default user profiles; by default, the symlinks under
3516 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3517 added with @command{guix build --root}, for example (@pxref{Invoking
3518 guix build}). The @command{guix gc --list-roots} command lists them.
3520 Prior to running @code{guix gc --collect-garbage} to make space, it is
3521 often useful to remove old generations from user profiles; that way, old
3522 package builds referenced by those generations can be reclaimed. This
3523 is achieved by running @code{guix package --delete-generations}
3524 (@pxref{Invoking guix package}).
3526 Our recommendation is to run a garbage collection periodically, or when
3527 you are short on disk space. For instance, to guarantee that at least
3528 5@tie{}GB are available on your disk, simply run:
3534 It is perfectly safe to run as a non-interactive periodic job
3535 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3536 Running @command{guix gc} with no arguments will collect as
3537 much garbage as it can, but that is often inconvenient: you may find
3538 yourself having to rebuild or re-download software that is ``dead'' from
3539 the GC viewpoint but that is necessary to build other pieces of
3540 software---e.g., the compiler tool chain.
3542 The @command{guix gc} command has three modes of operation: it can be
3543 used to garbage-collect any dead files (the default), to delete specific
3544 files (the @code{--delete} option), to print garbage-collector
3545 information, or for more advanced queries. The garbage collection
3546 options are as follows:
3549 @item --collect-garbage[=@var{min}]
3550 @itemx -C [@var{min}]
3551 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3552 sub-directories. This is the default operation when no option is
3555 When @var{min} is given, stop once @var{min} bytes have been collected.
3556 @var{min} may be a number of bytes, or it may include a unit as a
3557 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3558 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3560 When @var{min} is omitted, collect all the garbage.
3562 @item --free-space=@var{free}
3563 @itemx -F @var{free}
3564 Collect garbage until @var{free} space is available under
3565 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3566 as @code{500MiB}, as described above.
3568 When @var{free} or more is already available in @file{/gnu/store}, do
3569 nothing and exit immediately.
3571 @item --delete-generations[=@var{duration}]
3572 @itemx -d [@var{duration}]
3573 Before starting the garbage collection process, delete all the generations
3574 older than @var{duration}, for all the user profiles; when run as root, this
3575 applies to all the profiles @emph{of all the users}.
3577 For example, this command deletes all the generations of all your profiles
3578 that are older than 2 months (except generations that are current), and then
3579 proceeds to free space until at least 10 GiB are available:
3582 guix gc -d 2m -F 10G
3587 Attempt to delete all the store files and directories specified as
3588 arguments. This fails if some of the files are not in the store, or if
3589 they are still live.
3591 @item --list-failures
3592 List store items corresponding to cached build failures.
3594 This prints nothing unless the daemon was started with
3595 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3596 @option{--cache-failures}}).
3599 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3603 List store items in use by currently running processes. These store
3604 items are effectively considered GC roots: they cannot be deleted.
3606 @item --clear-failures
3607 Remove the specified store items from the failed-build cache.
3609 Again, this option only makes sense when the daemon is started with
3610 @option{--cache-failures}. Otherwise, it does nothing.
3613 Show the list of dead files and directories still present in the
3614 store---i.e., files and directories no longer reachable from any root.
3617 Show the list of live store files and directories.
3621 In addition, the references among existing store files can be queried:
3627 @cindex package dependencies
3628 List the references (respectively, the referrers) of store files given
3634 List the requisites of the store files passed as arguments. Requisites
3635 include the store files themselves, their references, and the references
3636 of these, recursively. In other words, the returned list is the
3637 @dfn{transitive closure} of the store files.
3639 @xref{Invoking guix size}, for a tool to profile the size of the closure
3640 of an element. @xref{Invoking guix graph}, for a tool to visualize
3641 the graph of references.
3645 Return the derivation(s) leading to the given store items
3646 (@pxref{Derivations}).
3648 For example, this command:
3651 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3655 returns the @file{.drv} file(s) leading to the @code{emacs} package
3656 installed in your profile.
3658 Note that there may be zero matching @file{.drv} files, for instance
3659 because these files have been garbage-collected. There can also be more
3660 than one matching @file{.drv} due to fixed-output derivations.
3663 Lastly, the following options allow you to check the integrity of the
3664 store and to control disk usage.
3668 @item --verify[=@var{options}]
3669 @cindex integrity, of the store
3670 @cindex integrity checking
3671 Verify the integrity of the store.
3673 By default, make sure that all the store items marked as valid in the
3674 database of the daemon actually exist in @file{/gnu/store}.
3676 When provided, @var{options} must be a comma-separated list containing one
3677 or more of @code{contents} and @code{repair}.
3679 When passing @option{--verify=contents}, the daemon computes the
3680 content hash of each store item and compares it against its hash in the
3681 database. Hash mismatches are reported as data corruptions. Because it
3682 traverses @emph{all the files in the store}, this command can take a
3683 long time, especially on systems with a slow disk drive.
3685 @cindex repairing the store
3686 @cindex corruption, recovering from
3687 Using @option{--verify=repair} or @option{--verify=contents,repair}
3688 causes the daemon to try to repair corrupt store items by fetching
3689 substitutes for them (@pxref{Substitutes}). Because repairing is not
3690 atomic, and thus potentially dangerous, it is available only to the
3691 system administrator. A lightweight alternative, when you know exactly
3692 which items in the store are corrupt, is @command{guix build --repair}
3693 (@pxref{Invoking guix build}).
3696 @cindex deduplication
3697 Optimize the store by hard-linking identical files---this is
3698 @dfn{deduplication}.
3700 The daemon performs deduplication after each successful build or archive
3701 import, unless it was started with @code{--disable-deduplication}
3702 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3703 this option is primarily useful when the daemon was running with
3704 @code{--disable-deduplication}.
3708 @node Invoking guix pull
3709 @section Invoking @command{guix pull}
3711 @cindex upgrading Guix
3712 @cindex updating Guix
3713 @cindex @command{guix pull}
3715 Packages are installed or upgraded to the latest version available in
3716 the distribution currently available on your local machine. To update
3717 that distribution, along with the Guix tools, you must run @command{guix
3718 pull}: the command downloads the latest Guix source code and package
3719 descriptions, and deploys it. Source code is downloaded from a
3720 @uref{https://git-scm.com, Git} repository, by default the official
3721 GNU@tie{}Guix repository, though this can be customized.
3723 Specifically, @command{guix pull} downloads code from the @dfn{channels}
3724 (@pxref{Channels}) specified by one of the followings, in this order:
3728 the @option{--channels} option;
3730 the user's @file{~/.config/guix/channels.scm} file;
3732 the system-wide @file{/etc/guix/channels.scm} file;
3734 the built-in default channels specified in the @code{%default-channels}
3738 On completion, @command{guix package} will use packages and package
3739 versions from this just-retrieved copy of Guix. Not only that, but all
3740 the Guix commands and Scheme modules will also be taken from that latest
3741 version. New @command{guix} sub-commands added by the update also
3744 Any user can update their Guix copy using @command{guix pull}, and the
3745 effect is limited to the user who ran @command{guix pull}. For
3746 instance, when user @code{root} runs @command{guix pull}, this has no
3747 effect on the version of Guix that user @code{alice} sees, and vice
3750 The result of running @command{guix pull} is a @dfn{profile} available
3751 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3752 make sure to add it to the beginning of your search path so that you use
3753 the latest version, and similarly for the Info manual
3754 (@pxref{Documentation}):
3757 export PATH="$HOME/.config/guix/current/bin:$PATH"
3758 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3761 The @code{--list-generations} or @code{-l} option lists past generations
3762 produced by @command{guix pull}, along with details about their provenance:
3766 Generation 1 Jun 10 2018 00:18:18
3768 repository URL: https://git.savannah.gnu.org/git/guix.git
3769 branch: origin/master
3770 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3772 Generation 2 Jun 11 2018 11:02:49
3774 repository URL: https://git.savannah.gnu.org/git/guix.git
3775 branch: origin/master
3776 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3777 2 new packages: keepalived, libnfnetlink
3778 6 packages upgraded: emacs-nix-mode@@2.0.4,
3779 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3780 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3782 Generation 3 Jun 13 2018 23:31:07 (current)
3784 repository URL: https://git.savannah.gnu.org/git/guix.git
3785 branch: origin/master
3786 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3787 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3788 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3791 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3792 describe the current status of Guix.
3794 This @code{~/.config/guix/current} profile works exactly like the profiles
3795 created by @command{guix package} (@pxref{Invoking guix package}). That
3796 is, you can list generations, roll back to the previous
3797 generation---i.e., the previous Guix---and so on:
3800 $ guix pull --roll-back
3801 switched from generation 3 to 2
3802 $ guix pull --delete-generations=1
3803 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3806 You can also use @command{guix package} (@pxref{Invoking guix package})
3807 to manage the profile by naming it explicitly:
3809 $ guix package -p ~/.config/guix/current --roll-back
3810 switched from generation 3 to 2
3811 $ guix package -p ~/.config/guix/current --delete-generations=1
3812 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3815 The @command{guix pull} command is usually invoked with no arguments,
3816 but it supports the following options:
3819 @item --url=@var{url}
3820 @itemx --commit=@var{commit}
3821 @itemx --branch=@var{branch}
3822 Download code for the @code{guix} channel from the specified @var{url}, at the
3823 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3824 string), or @var{branch}.
3826 @cindex @file{channels.scm}, configuration file
3827 @cindex configuration file for channels
3828 These options are provided for convenience, but you can also specify your
3829 configuration in the @file{~/.config/guix/channels.scm} file or using the
3830 @option{--channels} option (see below).
3832 @item --channels=@var{file}
3833 @itemx -C @var{file}
3834 Read the list of channels from @var{file} instead of
3835 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
3836 @var{file} must contain Scheme code that
3837 evaluates to a list of channel objects. @xref{Channels}, for more
3840 @cindex channel news
3843 Display the list of packages added or upgraded since the previous
3844 generation, as well as, occasionally, news written by channel authors
3845 for their users (@pxref{Channels, Writing Channel News}).
3847 The package information is the same as displayed upon @command{guix
3848 pull} completion, but without ellipses; it is also similar to the output
3849 of @command{guix pull -l} for the last generation (see below).
3851 @item --list-generations[=@var{pattern}]
3852 @itemx -l [@var{pattern}]
3853 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3854 is provided, the subset of generations that match @var{pattern}.
3855 The syntax of @var{pattern} is the same as with @code{guix package
3856 --list-generations} (@pxref{Invoking guix package}).
3859 @cindex rolling back
3860 @cindex undoing transactions
3861 @cindex transactions, undoing
3862 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
3863 undo the last transaction.
3865 @item --switch-generation=@var{pattern}
3866 @itemx -S @var{pattern}
3868 Switch to a particular generation defined by @var{pattern}.
3870 @var{pattern} may be either a generation number or a number prefixed
3871 with ``+'' or ``-''. The latter means: move forward/backward by a
3872 specified number of generations. For example, if you want to return to
3873 the latest generation after @code{--roll-back}, use
3874 @code{--switch-generation=+1}.
3876 @item --delete-generations[=@var{pattern}]
3877 @itemx -d [@var{pattern}]
3878 When @var{pattern} is omitted, delete all generations except the current
3881 This command accepts the same patterns as @option{--list-generations}.
3882 When @var{pattern} is specified, delete the matching generations. When
3883 @var{pattern} specifies a duration, generations @emph{older} than the
3884 specified duration match. For instance, @code{--delete-generations=1m}
3885 deletes generations that are more than one month old.
3887 If the current generation matches, it is @emph{not} deleted.
3889 Note that deleting generations prevents rolling back to them.
3890 Consequently, this command must be used with care.
3892 @xref{Invoking guix describe}, for a way to display information about the
3893 current generation only.
3895 @item --profile=@var{profile}
3896 @itemx -p @var{profile}
3897 Use @var{profile} instead of @file{~/.config/guix/current}.
3901 Show which channel commit(s) would be used and what would be built or
3902 substituted but do not actually do it.
3904 @item --system=@var{system}
3905 @itemx -s @var{system}
3906 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3907 the system type of the build host.
3910 Produce verbose output, writing build logs to the standard error output.
3913 Use the bootstrap Guile to build the latest Guix. This option is only
3914 useful to Guix developers.
3917 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3918 repository and branch to pull from, as well as @emph{additional} repositories
3919 containing package modules that should be deployed. @xref{Channels}, for more
3922 In addition, @command{guix pull} supports all the common build options
3923 (@pxref{Common Build Options}).
3929 @cindex @file{channels.scm}, configuration file
3930 @cindex configuration file for channels
3931 @cindex @command{guix pull}, configuration file
3932 @cindex configuration of @command{guix pull}
3933 Guix and its package collection are updated by running @command{guix pull}
3934 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3935 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3936 customized by defining @dfn{channels} in the
3937 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3938 of a Git repository to be deployed, and @command{guix pull} can be instructed
3939 to pull from one or more channels. In other words, channels can be used to
3940 @emph{customize} and to @emph{extend} Guix, as we will see below.
3942 @subsection Using a Custom Guix Channel
3944 The channel called @code{guix} specifies where Guix itself---its command-line
3945 tools as well as its package collection---should be downloaded. For instance,
3946 suppose you want to update from your own copy of the Guix repository at
3947 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3948 write in @code{~/.config/guix/channels.scm} this specification:
3951 ;; Tell 'guix pull' to use my own repo.
3954 (url "https://example.org/my-guix.git")
3955 (branch "super-hacks")))
3959 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3960 branch of the repository at @code{example.org}.
3962 @subsection Specifying Additional Channels
3964 @cindex extending the package collection (channels)
3965 @cindex personal packages (channels)
3966 @cindex channels, for personal packages
3967 You can also specify @emph{additional channels} to pull from. Let's say you
3968 have a bunch of custom package variants or personal packages that you think
3969 would make little sense to contribute to the Guix project, but would like to
3970 have these packages transparently available to you at the command line. You
3971 would first write modules containing those package definitions (@pxref{Package
3972 Modules}), maintain them in a Git repository, and then you and anyone else can
3973 use it as an additional channel to get packages from. Neat, no?
3975 @c What follows stems from discussions at
3976 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3977 @c earlier discussions on guix-devel@gnu.org.
3979 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3980 publish your personal channel to the world, we would like to share a few words
3985 Before publishing a channel, please consider contributing your package
3986 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3987 to free software of all sorts, and packages in Guix proper are readily
3988 available to all Guix users and benefit from the project's quality assurance
3992 When you maintain package definitions outside Guix, we, Guix developers,
3993 consider that @emph{the compatibility burden is on you}. Remember that
3994 package modules and package definitions are just Scheme code that uses various
3995 programming interfaces (APIs). We want to remain free to change these APIs to
3996 keep improving Guix, possibly in ways that break your channel. We never
3997 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
4001 Corollary: if you're using an external channel and that channel breaks, please
4002 @emph{report the issue to the channel authors}, not to the Guix project.
4005 You've been warned! Having said this, we believe external channels are a
4006 practical way to exert your freedom to augment Guix' package collection and to
4007 share your improvements, which are basic tenets of
4008 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
4009 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
4012 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
4013 @command{guix pull} to pull from it @emph{in addition} to the default Guix
4016 @vindex %default-channels
4018 ;; Add my personal packages to those Guix provides.
4020 (name 'my-personal-packages)
4021 (url "https://example.org/personal-packages.git"))
4026 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4027 add a channel the list of channels that the variable @code{%default-channels}
4028 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4029 Manual}). With this file in place, @command{guix pull} builds not only Guix
4030 but also the package modules from your own repository. The result in
4031 @file{~/.config/guix/current} is the union of Guix with your own package
4035 $ guix pull --list-generations
4037 Generation 19 Aug 27 2018 16:20:48
4039 repository URL: https://git.savannah.gnu.org/git/guix.git
4041 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4042 my-personal-packages dd3df5e
4043 repository URL: https://example.org/personal-packages.git
4045 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4046 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
4047 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4051 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4052 both Guix and packages from the @code{my-personal-packages} channel. Among
4053 the new and upgraded packages that are listed, some like @code{my-gimp} and
4054 @code{my-emacs-with-cool-features} might come from
4055 @code{my-personal-packages}, while others come from the Guix default channel.
4057 To create a channel, create a Git repository containing your own package
4058 modules and make it available. The repository can contain anything, but a
4059 useful channel will contain Guile modules that export packages. Once you
4060 start using a channel, Guix will behave as if the root directory of that
4061 channel's Git repository has been added to the Guile load path (@pxref{Load
4062 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
4063 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
4064 module, then the module will be available under the name @code{(my-packages
4065 my-tools)}, and you will be able to use it like any other module
4066 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
4068 @cindex dependencies, channels
4069 @cindex meta-data, channels
4070 @subsection Declaring Channel Dependencies
4072 Channel authors may decide to augment a package collection provided by other
4073 channels. They can declare their channel to be dependent on other channels in
4074 a meta-data file @file{.guix-channel}, which is to be placed in the root of
4075 the channel repository.
4077 The meta-data file should contain a simple S-expression like this:
4084 (name some-collection)
4085 (url "https://example.org/first-collection.git"))
4087 (name some-other-collection)
4088 (url "https://example.org/second-collection.git")
4089 (branch "testing"))))
4092 In the above example this channel is declared to depend on two other channels,
4093 which will both be fetched automatically. The modules provided by the channel
4094 will be compiled in an environment where the modules of all these declared
4095 channels are available.
4097 For the sake of reliability and maintainability, you should avoid dependencies
4098 on channels that you don't control, and you should aim to keep the number of
4099 dependencies to a minimum.
4101 @cindex subdirectory, channels
4102 @subsection Package Modules in a Sub-directory
4104 As a channel author, you may want to keep your channel modules in a
4105 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4106 add a meta-data file @file{.guix-channel} that contains:
4114 @cindex news, for channels
4115 @subsection Writing Channel News
4117 Channel authors may occasionally want to communicate to their users
4118 information about important changes in the channel. You'd send them all
4119 an email, but that's not convenient.
4121 Instead, channels can provide a @dfn{news file}; when the channel users
4122 run @command{guix pull}, that news file is automatically read and
4123 @command{guix pull --news} can display the announcements that correspond
4124 to the new commits that have been pulled, if any.
4126 To do that, channel authors must first declare the name of the news file
4127 in their @file{.guix-channel} file:
4132 (news-file "etc/news.txt"))
4135 The news file itself, @file{etc/news.txt} in this example, must look
4136 something like this:
4141 (entry (tag "the-bug-fix")
4142 (title (en "Fixed terrible bug")
4144 (body (en "@@emph@{Good news@}! It's fixed!")
4145 (eo "Certe ĝi pli bone funkcias nun!")))
4146 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4147 (title (en "Added a great package")
4148 (ca "Què vol dir guix?"))
4149 (body (en "Don't miss the @@code@{hello@} package!"))))
4152 The file consists of a list of @dfn{news entries}. Each entry is
4153 associated with a commit or tag: it describes changes made in this
4154 commit, possibly in preceding commits as well. Users see entries only
4155 the first time they obtain the commit the entry refers to.
4157 The @code{title} field should be a one-line summary while @code{body}
4158 can be arbitrarily long, and both can contain Texinfo markup
4159 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4160 a list of language tag/message tuples, which allows @command{guix pull}
4161 to display news in the language that corresponds to the user's locale.
4163 If you want to translate news using a gettext-based workflow, you can
4164 extract translatable strings with @command{xgettext} (@pxref{xgettext
4165 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4166 you write news entries in English first, the command below creates a PO
4167 file containing the strings to translate:
4170 xgettext -o news.po -l scheme -ken etc/news.scm
4173 To sum up, yes, you could use your channel as a blog. But beware, this
4174 is @emph{not quite} what your users might expect.
4176 @subsection Replicating Guix
4178 @cindex pinning, channels
4179 @cindex replicating Guix
4180 @cindex reproducibility, of Guix
4181 The @command{guix pull --list-generations} output above shows precisely which
4182 commits were used to build this instance of Guix. We can thus replicate it,
4183 say, on another machine, by providing a channel specification in
4184 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4187 ;; Deploy specific commits of my channels of interest.
4190 (url "https://git.savannah.gnu.org/git/guix.git")
4191 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
4193 (name 'my-personal-packages)
4194 (url "https://example.org/personal-packages.git")
4195 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4198 The @command{guix describe --format=channels} command can even generate this
4199 list of channels directly (@pxref{Invoking guix describe}). The resulting
4200 file can be used with the -C options of @command{guix pull}
4201 (@pxref{Invoking guix pull}) or @command{guix time-machine}
4202 (@pxref{Invoking guix time-machine}).
4204 At this point the two machines run the @emph{exact same Guix}, with access to
4205 the @emph{exact same packages}. The output of @command{guix build gimp} on
4206 one machine will be exactly the same, bit for bit, as the output of the same
4207 command on the other machine. It also means both machines have access to all
4208 the source code of Guix and, transitively, to all the source code of every
4211 This gives you super powers, allowing you to track the provenance of binary
4212 artifacts with very fine grain, and to reproduce software environments at
4213 will---some sort of ``meta reproducibility'' capabilities, if you will.
4214 @xref{Inferiors}, for another way to take advantage of these super powers.
4216 @node Invoking guix time-machine
4217 @section Invoking @command{guix time-machine}
4219 @cindex @command{guix time-machine}
4220 @cindex pinning, channels
4221 @cindex replicating Guix
4222 @cindex reproducibility, of Guix
4224 The @command{guix time-machine} command provides access to other
4225 revisions of Guix, for example to install older versions of packages,
4226 or to reproduce a computation in an identical environment. The revision
4227 of Guix to be used is defined by a commit or by a channel
4228 description file created by @command{guix describe}
4229 (@pxref{Invoking guix describe}).
4231 The general syntax is:
4234 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4237 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4238 @command{guix} command of the specified revision. The @var{options} that define
4239 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4242 @item --url=@var{url}
4243 @itemx --commit=@var{commit}
4244 @itemx --branch=@var{branch}
4245 Use the @code{guix} channel from the specified @var{url}, at the
4246 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4247 string), or @var{branch}.
4249 @item --channels=@var{file}
4250 @itemx -C @var{file}
4251 Read the list of channels from @var{file}. @var{file} must contain
4252 Scheme code that evaluates to a list of channel objects.
4253 @xref{Channels} for more information.
4256 As for @command{guix pull}, the absence of any options means that the
4257 the latest commit on the master branch will be used. The command
4260 guix time-machine -- build hello
4263 will thus build the package @code{hello} as defined in the master branch,
4264 which is in general a newer revision of Guix than you have installed.
4265 Time travel works in both directions!
4267 Note that @command{guix time-machine} can trigger builds of channels and
4268 their dependencies, and these are controlled by the standard build
4269 options (@pxref{Common Build Options}).
4274 @c TODO: Remove this once we're more confident about API stability.
4276 The functionality described here is a ``technology preview'' as of version
4277 @value{VERSION}. As such, the interface is subject to change.
4281 @cindex composition of Guix revisions
4282 Sometimes you might need to mix packages from the revision of Guix you're
4283 currently running with packages available in a different revision of Guix.
4284 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4285 revisions in arbitrary ways.
4287 @cindex inferior packages
4288 Technically, an ``inferior'' is essentially a separate Guix process connected
4289 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4290 @code{(guix inferior)} module allows you to create inferiors and to
4291 communicate with them. It also provides a high-level interface to browse and
4292 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4294 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4295 to interact with a separate revision of Guix. For example, let's assume you
4296 want to install in your profile the current @code{guile} package, along with
4297 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4298 because the newer @code{guile-json} has an incompatible API and you want to
4299 run your code against the old API@. To do that, you could write a manifest for
4300 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4301 manifest, you would create an inferior for that old Guix revision you care
4302 about, and you would look up the @code{guile-json} package in the inferior:
4305 (use-modules (guix inferior) (guix channels)
4306 (srfi srfi-1)) ;for 'first'
4309 ;; This is the old revision from which we want to
4310 ;; extract guile-json.
4313 (url "https://git.savannah.gnu.org/git/guix.git")
4315 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4318 ;; An inferior representing the above revision.
4319 (inferior-for-channels channels))
4321 ;; Now create a manifest with the current "guile" package
4322 ;; and the old "guile-json" package.
4324 (list (first (lookup-inferior-packages inferior "guile-json"))
4325 (specification->package "guile")))
4328 On its first run, @command{guix package --manifest} might have to build the
4329 channel you specified before it can create the inferior; subsequent runs will
4330 be much faster because the Guix revision will be cached.
4332 The @code{(guix inferior)} module provides the following procedures to open an
4335 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4336 [#:cache-directory] [#:ttl]
4337 Return an inferior for @var{channels}, a list of channels. Use the cache at
4338 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4339 This procedure opens a new connection to the build daemon.
4341 As a side effect, this procedure may build or substitute binaries for
4342 @var{channels}, which can take time.
4345 @deffn {Scheme Procedure} open-inferior @var{directory} @
4346 [#:command "bin/guix"]
4347 Open the inferior Guix in @var{directory}, running
4348 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4349 the inferior could not be launched.
4352 @cindex inferior packages
4353 The procedures listed below allow you to obtain and manipulate inferior
4356 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4357 Return the list of packages known to @var{inferior}.
4360 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4362 Return the sorted list of inferior packages matching @var{name} in
4363 @var{inferior}, with highest version numbers first. If @var{version} is true,
4364 return only packages with a version number prefixed by @var{version}.
4367 @deffn {Scheme Procedure} inferior-package? @var{obj}
4368 Return true if @var{obj} is an inferior package.
4371 @deffn {Scheme Procedure} inferior-package-name @var{package}
4372 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4373 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4374 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4375 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4376 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4377 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4378 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4379 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4380 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4381 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4382 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4383 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4384 These procedures are the counterpart of package record accessors
4385 (@pxref{package Reference}). Most of them work by querying the inferior
4386 @var{package} comes from, so the inferior must still be live when you call
4390 Inferior packages can be used transparently like any other package or
4391 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4392 transparently handled by the @code{packages->manifest} procedure, which is
4393 commonly use in manifests (@pxref{Invoking guix package, the
4394 @option{--manifest} option of @command{guix package}}). Thus you can insert
4395 an inferior package pretty much anywhere you would insert a regular package:
4396 in manifests, in the @code{packages} field of your @code{operating-system}
4397 declaration, and so on.
4399 @node Invoking guix describe
4400 @section Invoking @command{guix describe}
4402 @cindex reproducibility
4403 @cindex replicating Guix
4404 Often you may want to answer questions like: ``Which revision of Guix am I
4405 using?'' or ``Which channels am I using?'' This is useful information in many
4406 situations: if you want to @emph{replicate} an environment on a different
4407 machine or user account, if you want to report a bug or to determine what
4408 change in the channels you are using caused it, or if you want to record your
4409 system state for reproducibility purposes. The @command{guix describe}
4410 command answers these questions.
4412 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4413 displays the channel(s) that it was built from, including their repository URL
4414 and commit IDs (@pxref{Channels}):
4418 Generation 10 Sep 03 2018 17:32:44 (current)
4420 repository URL: https://git.savannah.gnu.org/git/guix.git
4422 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4425 If you're familiar with the Git version control system, this is similar in
4426 spirit to @command{git describe}; the output is also similar to that of
4427 @command{guix pull --list-generations}, but limited to the current generation
4428 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4429 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4430 information is all it takes to describe the revision of Guix you're using, and
4431 also to replicate it.
4433 To make it easier to replicate Guix, @command{guix describe} can also be asked
4434 to return a list of channels instead of the human-readable description above:
4437 $ guix describe -f channels
4440 (url "https://git.savannah.gnu.org/git/guix.git")
4442 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4446 You can save this to a file and feed it to @command{guix pull -C} on some
4447 other machine or at a later point in time, which will instantiate @emph{this
4448 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4449 From there on, since you're able to deploy the same revision of Guix, you can
4450 just as well @emph{replicate a complete software environment}. We humbly
4451 think that this is @emph{awesome}, and we hope you'll like it too!
4453 The details of the options supported by @command{guix describe} are as
4457 @item --format=@var{format}
4458 @itemx -f @var{format}
4459 Produce output in the specified @var{format}, one of:
4463 produce human-readable output;
4465 produce a list of channel specifications that can be passed to @command{guix
4466 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4470 produce a list of channel specifications in JSON format;
4472 produce a list of channel specifications in Recutils format.
4475 @item --profile=@var{profile}
4476 @itemx -p @var{profile}
4477 Display information about @var{profile}.
4480 @node Invoking guix archive
4481 @section Invoking @command{guix archive}
4483 @cindex @command{guix archive}
4485 The @command{guix archive} command allows users to @dfn{export} files
4486 from the store into a single archive, and to later @dfn{import} them on
4487 a machine that runs Guix.
4488 In particular, it allows store files to be transferred from one machine
4489 to the store on another machine.
4492 If you're looking for a way to produce archives in a format suitable for
4493 tools other than Guix, @pxref{Invoking guix pack}.
4496 @cindex exporting store items
4497 To export store files as an archive to standard output, run:
4500 guix archive --export @var{options} @var{specifications}...
4503 @var{specifications} may be either store file names or package
4504 specifications, as for @command{guix package} (@pxref{Invoking guix
4505 package}). For instance, the following command creates an archive
4506 containing the @code{gui} output of the @code{git} package and the main
4507 output of @code{emacs}:
4510 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4513 If the specified packages are not built yet, @command{guix archive}
4514 automatically builds them. The build process may be controlled with the
4515 common build options (@pxref{Common Build Options}).
4517 To transfer the @code{emacs} package to a machine connected over SSH,
4521 guix archive --export -r emacs | ssh the-machine guix archive --import
4525 Similarly, a complete user profile may be transferred from one machine
4526 to another like this:
4529 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4530 ssh the-machine guix archive --import
4534 However, note that, in both examples, all of @code{emacs} and the
4535 profile as well as all of their dependencies are transferred (due to
4536 @code{-r}), regardless of what is already available in the store on the
4537 target machine. The @code{--missing} option can help figure out which
4538 items are missing from the target store. The @command{guix copy}
4539 command simplifies and optimizes this whole process, so this is probably
4540 what you should use in this case (@pxref{Invoking guix copy}).
4542 @cindex nar, archive format
4543 @cindex normalized archive (nar)
4544 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4545 comparable in spirit to `tar', but with differences
4546 that make it more appropriate for our purposes. First, rather than
4547 recording all Unix metadata for each file, the nar format only mentions
4548 the file type (regular, directory, or symbolic link); Unix permissions
4549 and owner/group are dismissed. Second, the order in which directory
4550 entries are stored always follows the order of file names according to
4551 the C locale collation order. This makes archive production fully
4554 When exporting, the daemon digitally signs the contents of the archive,
4555 and that digital signature is appended. When importing, the daemon
4556 verifies the signature and rejects the import in case of an invalid
4557 signature or if the signing key is not authorized.
4558 @c FIXME: Add xref to daemon doc about signatures.
4560 The main options are:
4564 Export the specified store files or packages (see below.) Write the
4565 resulting archive to the standard output.
4567 Dependencies are @emph{not} included in the output, unless
4568 @code{--recursive} is passed.
4572 When combined with @code{--export}, this instructs @command{guix
4573 archive} to include dependencies of the given items in the archive.
4574 Thus, the resulting archive is self-contained: it contains the closure
4575 of the exported store items.
4578 Read an archive from the standard input, and import the files listed
4579 therein into the store. Abort if the archive has an invalid digital
4580 signature, or if it is signed by a public key not among the authorized
4581 keys (see @code{--authorize} below.)
4584 Read a list of store file names from the standard input, one per line,
4585 and write on the standard output the subset of these files missing from
4588 @item --generate-key[=@var{parameters}]
4589 @cindex signing, archives
4590 Generate a new key pair for the daemon. This is a prerequisite before
4591 archives can be exported with @code{--export}. Note that this operation
4592 usually takes time, because it needs to gather enough entropy to
4593 generate the key pair.
4595 The generated key pair is typically stored under @file{/etc/guix}, in
4596 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4597 key, which must be kept secret.) When @var{parameters} is omitted,
4598 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4599 versions before 1.6.0, it is a 4096-bit RSA key.
4600 Alternatively, @var{parameters} can specify
4601 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4602 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4603 Libgcrypt Reference Manual}).
4606 @cindex authorizing, archives
4607 Authorize imports signed by the public key passed on standard input.
4608 The public key must be in ``s-expression advanced format''---i.e., the
4609 same format as the @file{signing-key.pub} file.
4611 The list of authorized keys is kept in the human-editable file
4612 @file{/etc/guix/acl}. The file contains
4613 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4614 s-expressions''} and is structured as an access-control list in the
4615 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4618 @item --extract=@var{directory}
4619 @itemx -x @var{directory}
4620 Read a single-item archive as served by substitute servers
4621 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4622 low-level operation needed in only very narrow use cases; see below.
4624 For example, the following command extracts the substitute for Emacs
4625 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4629 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4630 | gunzip | guix archive -x /tmp/emacs
4633 Single-item archives are different from multiple-item archives produced
4634 by @command{guix archive --export}; they contain a single store item,
4635 and they do @emph{not} embed a signature. Thus this operation does
4636 @emph{no} signature verification and its output should be considered
4639 The primary purpose of this operation is to facilitate inspection of
4640 archive contents coming from possibly untrusted substitute servers
4641 (@pxref{Invoking guix challenge}).
4645 Read a single-item archive as served by substitute servers
4646 (@pxref{Substitutes}) and print the list of files it contains, as in
4651 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4652 | lzip -d | guix archive -t
4658 @c *********************************************************************
4660 @chapter Development
4662 @cindex software development
4663 If you are a software developer, Guix provides tools that you should find
4664 helpful---independently of the language you're developing in. This is what
4665 this chapter is about.
4667 The @command{guix environment} command provides a convenient way to set up
4668 @dfn{development environments} containing all the dependencies and tools
4669 necessary to work on the software package of your choice. The @command{guix
4670 pack} command allows you to create @dfn{application bundles} that can be
4671 easily distributed to users who do not run Guix.
4674 * Invoking guix environment:: Setting up development environments.
4675 * Invoking guix pack:: Creating software bundles.
4678 @node Invoking guix environment
4679 @section Invoking @command{guix environment}
4681 @cindex reproducible build environments
4682 @cindex development environments
4683 @cindex @command{guix environment}
4684 @cindex environment, package build environment
4685 The purpose of @command{guix environment} is to assist hackers in
4686 creating reproducible development environments without polluting their
4687 package profile. The @command{guix environment} tool takes one or more
4688 packages, builds all of their inputs, and creates a shell
4689 environment to use them.
4691 The general syntax is:
4694 guix environment @var{options} @var{package}@dots{}
4697 The following example spawns a new shell set up for the development of
4701 guix environment guile
4704 If the needed dependencies are not built yet, @command{guix environment}
4705 automatically builds them. The environment of the new shell is an augmented
4706 version of the environment that @command{guix environment} was run in.
4707 It contains the necessary search paths for building the given package
4708 added to the existing environment variables. To create a ``pure''
4709 environment, in which the original environment variables have been unset,
4710 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4711 environment variables such as @code{PATH} in their @file{~/.bashrc}
4712 file. As a consequence, when @code{guix environment} launches it, Bash
4713 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4714 environment variables. It is an error to define such environment
4715 variables in @file{.bashrc}; instead, they should be defined in
4716 @file{.bash_profile}, which is sourced only by log-in shells.
4717 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4718 details on Bash start-up files.}.
4720 @vindex GUIX_ENVIRONMENT
4721 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4722 variable in the shell it spawns; its value is the file name of the
4723 profile of this environment. This allows users to, say, define a
4724 specific prompt for development environments in their @file{.bashrc}
4725 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4728 if [ -n "$GUIX_ENVIRONMENT" ]
4730 export PS1="\u@@\h \w [dev]\$ "
4735 ...@: or to browse the profile:
4738 $ ls "$GUIX_ENVIRONMENT/bin"
4741 Additionally, more than one package may be specified, in which case the
4742 union of the inputs for the given packages are used. For example, the
4743 command below spawns a shell where all of the dependencies of both Guile
4744 and Emacs are available:
4747 guix environment guile emacs
4750 Sometimes an interactive shell session is not desired. An arbitrary
4751 command may be invoked by placing the @code{--} token to separate the
4752 command from the rest of the arguments:
4755 guix environment guile -- make -j4
4758 In other situations, it is more convenient to specify the list of
4759 packages needed in the environment. For example, the following command
4760 runs @command{python} from an environment containing Python@tie{}2.7 and
4764 guix environment --ad-hoc python2-numpy python-2.7 -- python
4767 Furthermore, one might want the dependencies of a package and also some
4768 additional packages that are not build-time or runtime dependencies, but
4769 are useful when developing nonetheless. Because of this, the
4770 @code{--ad-hoc} flag is positional. Packages appearing before
4771 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4772 added to the environment. Packages appearing after are interpreted as
4773 packages that will be added to the environment directly. For example,
4774 the following command creates a Guix development environment that
4775 additionally includes Git and strace:
4778 guix environment --pure guix --ad-hoc git strace
4781 Sometimes it is desirable to isolate the environment as much as
4782 possible, for maximal purity and reproducibility. In particular, when
4783 using Guix on a host distro that is not Guix System, it is desirable to
4784 prevent access to @file{/usr/bin} and other system-wide resources from
4785 the development environment. For example, the following command spawns
4786 a Guile REPL in a ``container'' where only the store and the current
4787 working directory are mounted:
4790 guix environment --ad-hoc --container guile -- guile
4794 The @code{--container} option requires Linux-libre 3.19 or newer.
4797 The available options are summarized below.
4800 @item --root=@var{file}
4801 @itemx -r @var{file}
4802 @cindex persistent environment
4803 @cindex garbage collector root, for environments
4804 Make @var{file} a symlink to the profile for this environment, and
4805 register it as a garbage collector root.
4807 This is useful if you want to protect your environment from garbage
4808 collection, to make it ``persistent''.
4810 When this option is omitted, the environment is protected from garbage
4811 collection only for the duration of the @command{guix environment}
4812 session. This means that next time you recreate the same environment,
4813 you could have to rebuild or re-download packages. @xref{Invoking guix
4814 gc}, for more on GC roots.
4816 @item --expression=@var{expr}
4817 @itemx -e @var{expr}
4818 Create an environment for the package or list of packages that
4819 @var{expr} evaluates to.
4821 For example, running:
4824 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4827 starts a shell with the environment for this specific variant of the
4833 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4836 starts a shell with all the base system packages available.
4838 The above commands only use the default output of the given packages.
4839 To select other outputs, two element tuples can be specified:
4842 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4845 @item --load=@var{file}
4846 @itemx -l @var{file}
4847 Create an environment for the package or list of packages that the code
4848 within @var{file} evaluates to.
4850 As an example, @var{file} might contain a definition like this
4851 (@pxref{Defining Packages}):
4854 @verbatiminclude environment-gdb.scm
4857 @item --manifest=@var{file}
4858 @itemx -m @var{file}
4859 Create an environment for the packages contained in the manifest object
4860 returned by the Scheme code in @var{file}. This option can be repeated
4861 several times, in which case the manifests are concatenated.
4863 This is similar to the same-named option in @command{guix package}
4864 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4868 Include all specified packages in the resulting environment, as if an
4869 @i{ad hoc} package were defined with them as inputs. This option is
4870 useful for quickly creating an environment without having to write a
4871 package expression to contain the desired inputs.
4873 For instance, the command:
4876 guix environment --ad-hoc guile guile-sdl -- guile
4879 runs @command{guile} in an environment where Guile and Guile-SDL are
4882 Note that this example implicitly asks for the default output of
4883 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4884 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4885 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4887 This option may be composed with the default behavior of @command{guix
4888 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4889 as packages whose dependencies will be added to the environment, the
4890 default behavior. Packages appearing after are interpreted as packages
4891 that will be added to the environment directly.
4894 Unset existing environment variables when building the new environment, except
4895 those specified with @option{--preserve} (see below.) This has the effect of
4896 creating an environment in which search paths only contain package inputs.
4898 @item --preserve=@var{regexp}
4899 @itemx -E @var{regexp}
4900 When used alongside @option{--pure}, preserve the environment variables
4901 matching @var{regexp}---in other words, put them on a ``white list'' of
4902 environment variables that must be preserved. This option can be repeated
4906 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4910 This example runs @command{mpirun} in a context where the only environment
4911 variables defined are @code{PATH}, environment variables whose name starts
4912 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4915 @item --search-paths
4916 Display the environment variable definitions that make up the
4919 @item --system=@var{system}
4920 @itemx -s @var{system}
4921 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4926 Run @var{command} within an isolated container. The current working
4927 directory outside the container is mapped inside the container.
4928 Additionally, unless overridden with @code{--user}, a dummy home
4929 directory is created that matches the current user's home directory, and
4930 @file{/etc/passwd} is configured accordingly.
4932 The spawned process runs as the current user outside the container. Inside
4933 the container, it has the same UID and GID as the current user, unless
4934 @option{--user} is passed (see below.)
4938 For containers, share the network namespace with the host system.
4939 Containers created without this flag only have access to the loopback
4942 @item --link-profile
4944 For containers, link the environment profile to
4945 @file{~/.guix-profile} within the container. This is equivalent to
4946 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4947 within the container. Linking will fail and abort the environment if
4948 the directory already exists, which will certainly be the case if
4949 @command{guix environment} was invoked in the user's home directory.
4951 Certain packages are configured to look in
4952 @code{~/.guix-profile} for configuration files and data;@footnote{For
4953 example, the @code{fontconfig} package inspects
4954 @file{~/.guix-profile/share/fonts} for additional fonts.}
4955 @code{--link-profile} allows these programs to behave as expected within
4958 @item --user=@var{user}
4959 @itemx -u @var{user}
4960 For containers, use the username @var{user} in place of the current
4961 user. The generated @file{/etc/passwd} entry within the container will
4962 contain the name @var{user}, the home directory will be
4963 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4964 the UID and GID inside the container are 1000. @var{user}
4965 need not exist on the system.
4967 Additionally, any shared or exposed path (see @code{--share} and
4968 @code{--expose} respectively) whose target is within the current user's
4969 home directory will be remapped relative to @file{/home/USER}; this
4970 includes the automatic mapping of the current working directory.
4973 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4975 guix environment --container --user=foo \
4976 --expose=$HOME/test \
4977 --expose=/tmp/target=$HOME/target
4980 While this will limit the leaking of user identity through home paths
4981 and each of the user fields, this is only one useful component of a
4982 broader privacy/anonymity solution---not one in and of itself.
4985 For containers, the default behavior is to share the current working
4986 directory with the isolated container and immediately change to that
4987 directory within the container. If this is undesirable, @code{--no-cwd}
4988 will cause the current working directory to @emph{not} be automatically
4989 shared and will change to the user's home directory within the container
4990 instead. See also @code{--user}.
4992 @item --expose=@var{source}[=@var{target}]
4993 @itemx --share=@var{source}[=@var{target}]
4994 For containers, @code{--expose} (resp. @code{--share}) exposes the file
4995 system @var{source} from the host system as the read-only
4996 (resp. writable) file system @var{target} within the container. If
4997 @var{target} is not specified, @var{source} is used as the target mount
4998 point in the container.
5000 The example below spawns a Guile REPL in a container in which the user's
5001 home directory is accessible read-only via the @file{/exchange}
5005 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5010 @command{guix environment}
5011 also supports all of the common build options that @command{guix
5012 build} supports (@pxref{Common Build Options}) as well as package
5013 transformation options (@pxref{Package Transformation Options}).
5015 @node Invoking guix pack
5016 @section Invoking @command{guix pack}
5018 Occasionally you want to pass software to people who are not (yet!)
5019 lucky enough to be using Guix. You'd tell them to run @command{guix
5020 package -i @var{something}}, but that's not possible in this case. This
5021 is where @command{guix pack} comes in.
5024 If you are looking for ways to exchange binaries among machines that
5025 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5026 publish}, and @ref{Invoking guix archive}.
5031 @cindex application bundle
5032 @cindex software bundle
5033 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5034 @dfn{software bundle}: it creates a tarball or some other archive
5035 containing the binaries of the software you're interested in, and all
5036 its dependencies. The resulting archive can be used on any machine that
5037 does not have Guix, and people can run the exact same binaries as those
5038 you have with Guix. The pack itself is created in a bit-reproducible
5039 fashion, so anyone can verify that it really contains the build results
5040 that you pretend to be shipping.
5042 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5043 their dependencies, you can run:
5046 $ guix pack guile emacs geiser
5048 /gnu/store/@dots{}-pack.tar.gz
5051 The result here is a tarball containing a @file{/gnu/store} directory
5052 with all the relevant packages. The resulting tarball contains a
5053 @dfn{profile} with the three packages of interest; the profile is the
5054 same as would be created by @command{guix package -i}. It is this
5055 mechanism that is used to create Guix's own standalone binary tarball
5056 (@pxref{Binary Installation}).
5058 Users of this pack would have to run
5059 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5060 find inconvenient. To work around it, you can create, say, a
5061 @file{/opt/gnu/bin} symlink to the profile:
5064 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5068 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5070 @cindex relocatable binaries, with @command{guix pack}
5071 What if the recipient of your pack does not have root privileges on
5072 their machine, and thus cannot unpack it in the root file system? In
5073 that case, you will want to use the @code{--relocatable} option (see
5074 below). This option produces @dfn{relocatable binaries}, meaning they
5075 they can be placed anywhere in the file system hierarchy: in the example
5076 above, users can unpack your tarball in their home directory and
5077 directly run @file{./opt/gnu/bin/guile}.
5079 @cindex Docker, build an image with guix pack
5080 Alternatively, you can produce a pack in the Docker image format using
5081 the following command:
5084 guix pack -f docker -S /bin=bin guile guile-readline
5088 The result is a tarball that can be passed to the @command{docker load}
5089 command, followed by @code{docker run}:
5092 docker load < @var{file}
5093 docker run -ti guile-guile-readline /bin/guile
5097 where @var{file} is the image returned by @var{guix pack}, and
5098 @code{guile-guile-readline} is its ``image tag''. See the
5099 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5100 documentation} for more information.
5102 @cindex Singularity, build an image with guix pack
5103 @cindex SquashFS, build an image with guix pack
5104 Yet another option is to produce a SquashFS image with the following
5108 guix pack -f squashfs bash guile emacs geiser
5112 The result is a SquashFS file system image that can either be mounted or
5113 directly be used as a file system container image with the
5114 @uref{https://singularity.lbl.gov, Singularity container execution
5115 environment}, using commands like @command{singularity shell} or
5116 @command{singularity exec}.
5118 Several command-line options allow you to customize your pack:
5121 @item --format=@var{format}
5122 @itemx -f @var{format}
5123 Produce a pack in the given @var{format}.
5125 The available formats are:
5129 This is the default format. It produces a tarball containing all the
5130 specified binaries and symlinks.
5133 This produces a tarball that follows the
5134 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5135 Docker Image Specification}. The ``repository name'' as it appears in
5136 the output of the @command{docker images} command is computed from
5137 package names passed on the command line or in the manifest file.
5140 This produces a SquashFS image containing all the specified binaries and
5141 symlinks, as well as empty mount points for virtual file systems like
5145 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5146 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5147 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5148 with something like:
5151 guix pack -f squashfs bash @dots{}
5154 If you forget the @code{bash} (or similar) package, @command{singularity
5155 run} and @command{singularity exec} will fail with an unhelpful ``no
5156 such file or directory'' message.
5160 @cindex relocatable binaries
5163 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5164 anywhere in the file system hierarchy and run from there.
5166 When this option is passed once, the resulting binaries require support for
5167 @dfn{user namespaces} in the kernel Linux; when passed
5168 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5169 PRoot support, can be thought of as the abbreviation of ``Really
5170 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
5171 if user namespaces are unavailable, and essentially work anywhere---see below
5172 for the implications.
5174 For example, if you create a pack containing Bash with:
5177 guix pack -RR -S /mybin=bin bash
5181 ...@: you can copy that pack to a machine that lacks Guix, and from your
5182 home directory as a normal user, run:
5190 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5191 @file{/gnu/store} shows up and contains all the dependencies of
5192 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5193 altogether! That is probably the simplest way to deploy Guix-built
5194 software on a non-Guix machine.
5197 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5198 the kernel Linux, which allows unprivileged users to mount or change root.
5199 Old versions of Linux did not support it, and some GNU/Linux distributions
5202 To produce relocatable binaries that work even in the absence of user
5203 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5204 case, binaries will try user namespace support and fall back to PRoot if user
5205 namespaces are not supported.
5207 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
5208 support for file system virtualization. It achieves that by using the
5209 @code{ptrace} system call on the running program. This approach has the
5210 advantage to work without requiring special kernel support, but it incurs
5211 run-time overhead every time a system call is made.
5214 @cindex entry point, for Docker images
5215 @item --entry-point=@var{command}
5216 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5217 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5218 support it. @var{command} must be relative to the profile contained in the
5221 The entry point specifies the command that tools like @code{docker run} or
5222 @code{singularity run} automatically start by default. For example, you can
5226 guix pack -f docker --entry-point=bin/guile guile
5229 The resulting pack can easily be loaded and @code{docker run} with no extra
5230 arguments will spawn @code{bin/guile}:
5233 docker load -i pack.tar.gz
5234 docker run @var{image-id}
5237 @item --expression=@var{expr}
5238 @itemx -e @var{expr}
5239 Consider the package @var{expr} evaluates to.
5241 This has the same purpose as the same-named option in @command{guix
5242 build} (@pxref{Additional Build Options, @code{--expression} in
5243 @command{guix build}}).
5245 @item --manifest=@var{file}
5246 @itemx -m @var{file}
5247 Use the packages contained in the manifest object returned by the Scheme
5248 code in @var{file}. This option can be repeated several times, in which
5249 case the manifests are concatenated.
5251 This has a similar purpose as the same-named option in @command{guix
5252 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5253 same manifest files. It allows you to define a collection of packages
5254 once and use it both for creating profiles and for creating archives
5255 for use on machines that do not have Guix installed. Note that you can
5256 specify @emph{either} a manifest file @emph{or} a list of packages,
5259 @item --system=@var{system}
5260 @itemx -s @var{system}
5261 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5262 the system type of the build host.
5264 @item --target=@var{triplet}
5265 @cindex cross-compilation
5266 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5267 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
5268 configuration triplets,, autoconf, Autoconf}).
5270 @item --compression=@var{tool}
5271 @itemx -C @var{tool}
5272 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5273 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
5275 @item --symlink=@var{spec}
5276 @itemx -S @var{spec}
5277 Add the symlinks specified by @var{spec} to the pack. This option can
5278 appear several times.
5280 @var{spec} has the form @code{@var{source}=@var{target}}, where
5281 @var{source} is the symlink that will be created and @var{target} is the
5284 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5285 symlink pointing to the @file{bin} sub-directory of the profile.
5287 @item --save-provenance
5288 Save provenance information for the packages passed on the command line.
5289 Provenance information includes the URL and commit of the channels in use
5292 Provenance information is saved in the
5293 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5294 usual package metadata---the name and version of each package, their
5295 propagated inputs, and so on. It is useful information to the recipient of
5296 the pack, who then knows how the pack was (supposedly) obtained.
5298 This option is not enabled by default because, like timestamps, provenance
5299 information contributes nothing to the build process. In other words, there
5300 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5301 Recording such ``silent'' metadata in the output thus potentially breaks the
5302 source-to-binary bitwise reproducibility property.
5304 @item --root=@var{file}
5305 @itemx -r @var{file}
5306 @cindex garbage collector root, for packs
5307 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5310 @item --localstatedir
5311 @itemx --profile-name=@var{name}
5312 Include the ``local state directory'', @file{/var/guix}, in the resulting
5313 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5314 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5315 @file{~root/.guix-profile}.
5317 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5318 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5319 the pack means that the store is ``complete'' and manageable by Guix;
5320 not providing it pack means that the store is ``dead'': items cannot be
5321 added to it or removed from it after extraction of the pack.
5323 One use case for this is the Guix self-contained binary tarball
5324 (@pxref{Binary Installation}).
5328 Print the name of the derivation that builds the pack.
5331 Use the bootstrap binaries to build the pack. This option is only
5332 useful to Guix developers.
5335 In addition, @command{guix pack} supports all the common build options
5336 (@pxref{Common Build Options}) and all the package transformation
5337 options (@pxref{Package Transformation Options}).
5340 @c *********************************************************************
5341 @node Programming Interface
5342 @chapter Programming Interface
5344 GNU Guix provides several Scheme programming interfaces (APIs) to
5345 define, build, and query packages. The first interface allows users to
5346 write high-level package definitions. These definitions refer to
5347 familiar packaging concepts, such as the name and version of a package,
5348 its build system, and its dependencies. These definitions can then be
5349 turned into concrete build actions.
5351 Build actions are performed by the Guix daemon, on behalf of users. In a
5352 standard setup, the daemon has write access to the store---the
5353 @file{/gnu/store} directory---whereas users do not. The recommended
5354 setup also has the daemon perform builds in chroots, under a specific
5355 build users, to minimize interference with the rest of the system.
5358 Lower-level APIs are available to interact with the daemon and the
5359 store. To instruct the daemon to perform a build action, users actually
5360 provide it with a @dfn{derivation}. A derivation is a low-level
5361 representation of the build actions to be taken, and the environment in
5362 which they should occur---derivations are to package definitions what
5363 assembly is to C programs. The term ``derivation'' comes from the fact
5364 that build results @emph{derive} from them.
5366 This chapter describes all these APIs in turn, starting from high-level
5367 package definitions.
5370 * Package Modules:: Packages from the programmer's viewpoint.
5371 * Defining Packages:: Defining new packages.
5372 * Build Systems:: Specifying how packages are built.
5373 * The Store:: Manipulating the package store.
5374 * Derivations:: Low-level interface to package derivations.
5375 * The Store Monad:: Purely functional interface to the store.
5376 * G-Expressions:: Manipulating build expressions.
5377 * Invoking guix repl:: Fiddling with Guix interactively.
5380 @node Package Modules
5381 @section Package Modules
5383 From a programming viewpoint, the package definitions of the
5384 GNU distribution are provided by Guile modules in the @code{(gnu packages
5385 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5386 packages @dots{})} module name space are not necessarily ``GNU
5387 packages''. This module naming scheme follows the usual Guile module
5388 naming convention: @code{gnu} means that these modules are distributed
5389 as part of the GNU system, and @code{packages} identifies modules that
5390 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5391 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5392 module exports a variable named @code{emacs}, which is bound to a
5393 @code{<package>} object (@pxref{Defining Packages}).
5395 The @code{(gnu packages @dots{})} module name space is
5396 automatically scanned for packages by the command-line tools. For
5397 instance, when running @code{guix install emacs}, all the @code{(gnu
5398 packages @dots{})} modules are scanned until one that exports a package
5399 object whose name is @code{emacs} is found. This package search
5400 facility is implemented in the @code{(gnu packages)} module.
5402 @cindex customization, of packages
5403 @cindex package module search path
5404 Users can store package definitions in modules with different
5405 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5406 name and module name must match. For instance, the @code{(my-packages
5407 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5408 relative to the load path specified with @option{--load-path} or
5409 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5410 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5411 these package definitions visible to the user interfaces:
5415 By adding the directory containing your package modules to the search path
5416 with the @code{-L} flag of @command{guix package} and other commands
5417 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5418 environment variable described below.
5421 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5422 pulls from it. A channel is essentially a Git repository containing package
5423 modules. @xref{Channels}, for more information on how to define and use
5427 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5429 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5430 This is a colon-separated list of directories to search for additional
5431 package modules. Directories listed in this variable take precedence
5432 over the own modules of the distribution.
5435 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5436 each package is built based solely on other packages in the
5437 distribution. The root of this dependency graph is a small set of
5438 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5439 bootstrap)} module. For more information on bootstrapping,
5440 @pxref{Bootstrapping}.
5442 @node Defining Packages
5443 @section Defining Packages
5445 The high-level interface to package definitions is implemented in the
5446 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5447 example, the package definition, or @dfn{recipe}, for the GNU Hello
5448 package looks like this:
5451 (define-module (gnu packages hello)
5452 #:use-module (guix packages)
5453 #:use-module (guix download)
5454 #:use-module (guix build-system gnu)
5455 #:use-module (guix licenses)
5456 #:use-module (gnu packages gawk))
5458 (define-public hello
5464 (uri (string-append "mirror://gnu/hello/hello-" version
5468 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5469 (build-system gnu-build-system)
5470 (arguments '(#:configure-flags '("--enable-silent-rules")))
5471 (inputs `(("gawk" ,gawk)))
5472 (synopsis "Hello, GNU world: An example GNU package")
5473 (description "Guess what GNU Hello prints!")
5474 (home-page "https://www.gnu.org/software/hello/")
5479 Without being a Scheme expert, the reader may have guessed the meaning
5480 of the various fields here. This expression binds the variable
5481 @code{hello} to a @code{<package>} object, which is essentially a record
5482 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5483 This package object can be inspected using procedures found in the
5484 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5485 returns---surprise!---@code{"hello"}.
5487 With luck, you may be able to import part or all of the definition of
5488 the package you are interested in from another repository, using the
5489 @code{guix import} command (@pxref{Invoking guix import}).
5491 In the example above, @var{hello} is defined in a module of its own,
5492 @code{(gnu packages hello)}. Technically, this is not strictly
5493 necessary, but it is convenient to do so: all the packages defined in
5494 modules under @code{(gnu packages @dots{})} are automatically known to
5495 the command-line tools (@pxref{Package Modules}).
5497 There are a few points worth noting in the above package definition:
5501 The @code{source} field of the package is an @code{<origin>} object
5502 (@pxref{origin Reference}, for the complete reference).
5503 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5504 meaning that the source is a file to be downloaded over FTP or HTTP.
5506 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5507 the GNU mirrors defined in @code{(guix download)}.
5509 The @code{sha256} field specifies the expected SHA256 hash of the file
5510 being downloaded. It is mandatory, and allows Guix to check the
5511 integrity of the file. The @code{(base32 @dots{})} form introduces the
5512 base32 representation of the hash. You can obtain this information with
5513 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5514 hash} (@pxref{Invoking guix hash}).
5517 When needed, the @code{origin} form can also have a @code{patches} field
5518 listing patches to be applied, and a @code{snippet} field giving a
5519 Scheme expression to modify the source code.
5522 @cindex GNU Build System
5523 The @code{build-system} field specifies the procedure to build the
5524 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5525 represents the familiar GNU Build System, where packages may be
5526 configured, built, and installed with the usual @code{./configure &&
5527 make && make check && make install} command sequence.
5530 The @code{arguments} field specifies options for the build system
5531 (@pxref{Build Systems}). Here it is interpreted by
5532 @var{gnu-build-system} as a request run @file{configure} with the
5533 @code{--enable-silent-rules} flag.
5539 What about these quote (@code{'}) characters? They are Scheme syntax to
5540 introduce a literal list; @code{'} is synonymous with @code{quote}.
5541 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5542 for details. Here the value of the @code{arguments} field is a list of
5543 arguments passed to the build system down the road, as with @code{apply}
5544 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5547 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5548 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5549 @code{#:configure-flags} is a keyword used to pass a keyword argument
5550 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5554 The @code{inputs} field specifies inputs to the build process---i.e.,
5555 build-time or run-time dependencies of the package. Here, we define an
5556 input called @code{"gawk"} whose value is that of the @var{gawk}
5557 variable; @var{gawk} is itself bound to a @code{<package>} object.
5559 @cindex backquote (quasiquote)
5562 @cindex comma (unquote)
5566 @findex unquote-splicing
5567 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5568 us to introduce a literal list in the @code{inputs} field, while
5569 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5570 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5573 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5574 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5575 of ensuring that they are present (@pxref{Build Systems}).
5577 However, any other dependencies need to be specified in the
5578 @code{inputs} field. Any dependency not specified here will simply be
5579 unavailable to the build process, possibly leading to a build failure.
5582 @xref{package Reference}, for a full description of possible fields.
5584 Once a package definition is in place, the
5585 package may actually be built using the @code{guix build} command-line
5586 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5587 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5588 package definition using the @command{guix edit} command
5589 (@pxref{Invoking guix edit}).
5590 @xref{Packaging Guidelines}, for
5591 more information on how to test package definitions, and
5592 @ref{Invoking guix lint}, for information on how to check a definition
5593 for style conformance.
5594 @vindex GUIX_PACKAGE_PATH
5595 Lastly, @pxref{Channels}, for information
5596 on how to extend the distribution by adding your own package definitions
5599 Finally, updating the package definition to a new upstream version
5600 can be partly automated by the @command{guix refresh} command
5601 (@pxref{Invoking guix refresh}).
5603 Behind the scenes, a derivation corresponding to the @code{<package>}
5604 object is first computed by the @code{package-derivation} procedure.
5605 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5606 The build actions it prescribes may then be realized by using the
5607 @code{build-derivations} procedure (@pxref{The Store}).
5609 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5610 Return the @code{<derivation>} object of @var{package} for @var{system}
5611 (@pxref{Derivations}).
5613 @var{package} must be a valid @code{<package>} object, and @var{system}
5614 must be a string denoting the target system type---e.g.,
5615 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5616 must be a connection to the daemon, which operates on the store
5617 (@pxref{The Store}).
5621 @cindex cross-compilation
5622 Similarly, it is possible to compute a derivation that cross-builds a
5623 package for some other system:
5625 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5626 @var{package} @var{target} [@var{system}]
5627 Return the @code{<derivation>} object of @var{package} cross-built from
5628 @var{system} to @var{target}.
5630 @var{target} must be a valid GNU triplet denoting the target hardware
5631 and operating system, such as @code{"mips64el-linux-gnu"}
5632 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5635 @cindex package transformations
5636 @cindex input rewriting
5637 @cindex dependency tree rewriting
5638 Packages can be manipulated in arbitrary ways. An example of a useful
5639 transformation is @dfn{input rewriting}, whereby the dependency tree of
5640 a package is rewritten by replacing specific inputs by others:
5642 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5643 [@var{rewrite-name}]
5644 Return a procedure that, when passed a package, replaces its direct and
5645 indirect dependencies (but not its implicit inputs) according to
5646 @var{replacements}. @var{replacements} is a list of package pairs; the
5647 first element of each pair is the package to replace, and the second one
5650 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5651 the name of a package and returns its new name after rewrite.
5655 Consider this example:
5658 (define libressl-instead-of-openssl
5659 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5661 (package-input-rewriting `((,openssl . ,libressl))))
5663 (define git-with-libressl
5664 (libressl-instead-of-openssl git))
5668 Here we first define a rewriting procedure that replaces @var{openssl}
5669 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5670 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5671 This is exactly what the @option{--with-input} command-line option does
5672 (@pxref{Package Transformation Options, @option{--with-input}}).
5674 The following variant of @code{package-input-rewriting} can match packages to
5675 be replaced by name rather than by identity.
5677 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5678 Return a procedure that, given a package, applies the given @var{replacements} to
5679 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5680 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5681 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5682 replacement for that package.
5685 The example above could be rewritten this way:
5688 (define libressl-instead-of-openssl
5689 ;; Replace all the packages called "openssl" with LibreSSL.
5690 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5693 The key difference here is that, this time, packages are matched by spec and
5694 not by identity. In other words, any package in the graph that is called
5695 @code{openssl} will be replaced.
5697 A more generic procedure to rewrite a package dependency graph is
5698 @code{package-mapping}: it supports arbitrary changes to nodes in the
5701 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5702 Return a procedure that, given a package, applies @var{proc} to all the packages
5703 depended on and returns the resulting package. The procedure stops recursion
5704 when @var{cut?} returns true for a given package.
5708 * package Reference:: The package data type.
5709 * origin Reference:: The origin data type.
5713 @node package Reference
5714 @subsection @code{package} Reference
5716 This section summarizes all the options available in @code{package}
5717 declarations (@pxref{Defining Packages}).
5719 @deftp {Data Type} package
5720 This is the data type representing a package recipe.
5724 The name of the package, as a string.
5726 @item @code{version}
5727 The version of the package, as a string.
5730 An object telling how the source code for the package should be
5731 acquired. Most of the time, this is an @code{origin} object, which
5732 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5733 can also be any other ``file-like'' object such as a @code{local-file},
5734 which denotes a file from the local file system (@pxref{G-Expressions,
5735 @code{local-file}}).
5737 @item @code{build-system}
5738 The build system that should be used to build the package (@pxref{Build
5741 @item @code{arguments} (default: @code{'()})
5742 The arguments that should be passed to the build system. This is a
5743 list, typically containing sequential keyword-value pairs.
5745 @item @code{inputs} (default: @code{'()})
5746 @itemx @code{native-inputs} (default: @code{'()})
5747 @itemx @code{propagated-inputs} (default: @code{'()})
5748 @cindex inputs, of packages
5749 These fields list dependencies of the package. Each one is a list of
5750 tuples, where each tuple has a label for the input (a string) as its
5751 first element, a package, origin, or derivation as its second element,
5752 and optionally the name of the output thereof that should be used, which
5753 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5754 more on package outputs). For example, the list below specifies three
5758 `(("libffi" ,libffi)
5759 ("libunistring" ,libunistring)
5760 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5763 @cindex cross compilation, package dependencies
5764 The distinction between @code{native-inputs} and @code{inputs} is
5765 necessary when considering cross-compilation. When cross-compiling,
5766 dependencies listed in @code{inputs} are built for the @emph{target}
5767 architecture; conversely, dependencies listed in @code{native-inputs}
5768 are built for the architecture of the @emph{build} machine.
5770 @code{native-inputs} is typically used to list tools needed at
5771 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5772 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5773 this area (@pxref{Invoking guix lint}).
5775 @anchor{package-propagated-inputs}
5776 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5777 specified packages will be automatically installed alongside the package
5778 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5779 package}}, for information on how @command{guix package} deals with
5782 For example this is necessary when a C/C++ library needs headers of
5783 another library to compile, or when a pkg-config file refers to another
5784 one @i{via} its @code{Requires} field.
5786 Another example where @code{propagated-inputs} is useful is for languages
5787 that lack a facility to record the run-time search path akin to the
5788 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5789 more. To ensure that libraries written in those languages can find
5790 library code they depend on at run time, run-time dependencies must be
5791 listed in @code{propagated-inputs} rather than @code{inputs}.
5793 @item @code{outputs} (default: @code{'("out")})
5794 The list of output names of the package. @xref{Packages with Multiple
5795 Outputs}, for typical uses of additional outputs.
5797 @item @code{native-search-paths} (default: @code{'()})
5798 @itemx @code{search-paths} (default: @code{'()})
5799 A list of @code{search-path-specification} objects describing
5800 search-path environment variables honored by the package.
5802 @item @code{replacement} (default: @code{#f})
5803 This must be either @code{#f} or a package object that will be used as a
5804 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5807 @item @code{synopsis}
5808 A one-line description of the package.
5810 @item @code{description}
5811 A more elaborate description of the package.
5813 @item @code{license}
5814 @cindex license, of packages
5815 The license of the package; a value from @code{(guix licenses)},
5816 or a list of such values.
5818 @item @code{home-page}
5819 The URL to the home-page of the package, as a string.
5821 @item @code{supported-systems} (default: @code{%supported-systems})
5822 The list of systems supported by the package, as strings of the form
5823 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5825 @item @code{location} (default: source location of the @code{package} form)
5826 The source location of the package. It is useful to override this when
5827 inheriting from another package, in which case this field is not
5828 automatically corrected.
5832 @deffn {Scheme Syntax} this-package
5833 When used in the @emph{lexical scope} of a package field definition, this
5834 identifier resolves to the package being defined.
5836 The example below shows how to add a package as a native input of itself when
5844 ;; When cross-compiled, Guile, for example, depends on
5845 ;; a native version of itself. Add it here.
5846 (native-inputs (if (%current-target-system)
5847 `(("self" ,this-package))
5851 It is an error to refer to @code{this-package} outside a package definition.
5854 @node origin Reference
5855 @subsection @code{origin} Reference
5857 This section summarizes all the options available in @code{origin}
5858 declarations (@pxref{Defining Packages}).
5860 @deftp {Data Type} origin
5861 This is the data type representing a source code origin.
5865 An object containing the URI of the source. The object type depends on
5866 the @code{method} (see below). For example, when using the
5867 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5868 values are: a URL represented as a string, or a list thereof.
5871 A procedure that handles the URI.
5876 @item @var{url-fetch} from @code{(guix download)}
5877 download a file from the HTTP, HTTPS, or FTP URL specified in the
5881 @item @var{git-fetch} from @code{(guix git-download)}
5882 clone the Git version control repository, and check out the revision
5883 specified in the @code{uri} field as a @code{git-reference} object; a
5884 @code{git-reference} looks like this:
5888 (url "https://git.savannah.gnu.org/git/hello.git")
5894 A bytevector containing the SHA-256 hash of the source. Typically the
5895 @code{base32} form is used here to generate the bytevector from a
5898 You can obtain this information using @code{guix download}
5899 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5902 @item @code{file-name} (default: @code{#f})
5903 The file name under which the source code should be saved. When this is
5904 @code{#f}, a sensible default value will be used in most cases. In case
5905 the source is fetched from a URL, the file name from the URL will be
5906 used. For version control checkouts, it is recommended to provide the
5907 file name explicitly because the default is not very descriptive.
5909 @item @code{patches} (default: @code{'()})
5910 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5911 file-like objects}) pointing to patches to be applied to the source.
5913 This list of patches must be unconditional. In particular, it cannot
5914 depend on the value of @code{%current-system} or
5915 @code{%current-target-system}.
5917 @item @code{snippet} (default: @code{#f})
5918 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5919 in the source directory. This is a convenient way to modify the source,
5920 sometimes more convenient than a patch.
5922 @item @code{patch-flags} (default: @code{'("-p1")})
5923 A list of command-line flags that should be passed to the @code{patch}
5926 @item @code{patch-inputs} (default: @code{#f})
5927 Input packages or derivations to the patching process. When this is
5928 @code{#f}, the usual set of inputs necessary for patching are provided,
5929 such as GNU@tie{}Patch.
5931 @item @code{modules} (default: @code{'()})
5932 A list of Guile modules that should be loaded during the patching
5933 process and while running the code in the @code{snippet} field.
5935 @item @code{patch-guile} (default: @code{#f})
5936 The Guile package that should be used in the patching process. When
5937 this is @code{#f}, a sensible default is used.
5943 @section Build Systems
5945 @cindex build system
5946 Each package definition specifies a @dfn{build system} and arguments for
5947 that build system (@pxref{Defining Packages}). This @code{build-system}
5948 field represents the build procedure of the package, as well as implicit
5949 dependencies of that build procedure.
5951 Build systems are @code{<build-system>} objects. The interface to
5952 create and manipulate them is provided by the @code{(guix build-system)}
5953 module, and actual build systems are exported by specific modules.
5955 @cindex bag (low-level package representation)
5956 Under the hood, build systems first compile package objects to
5957 @dfn{bags}. A @dfn{bag} is like a package, but with less
5958 ornamentation---in other words, a bag is a lower-level representation of
5959 a package, which includes all the inputs of that package, including some
5960 that were implicitly added by the build system. This intermediate
5961 representation is then compiled to a derivation (@pxref{Derivations}).
5963 Build systems accept an optional list of @dfn{arguments}. In package
5964 definitions, these are passed @i{via} the @code{arguments} field
5965 (@pxref{Defining Packages}). They are typically keyword arguments
5966 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5967 Guile Reference Manual}). The value of these arguments is usually
5968 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5969 by the daemon (@pxref{Derivations}).
5971 The main build system is @code{gnu-build-system}, which implements the
5972 standard build procedure for GNU and many other packages. It
5973 is provided by the @code{(guix build-system gnu)} module.
5975 @defvr {Scheme Variable} gnu-build-system
5976 @code{gnu-build-system} represents the GNU Build System, and variants
5977 thereof (@pxref{Configuration, configuration and makefile conventions,,
5978 standards, GNU Coding Standards}).
5980 @cindex build phases
5981 In a nutshell, packages using it are configured, built, and installed with
5982 the usual @code{./configure && make && make check && make install}
5983 command sequence. In practice, a few additional steps are often needed.
5984 All these steps are split up in separate @dfn{phases},
5985 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5986 modules for more details about the build phases.}:
5990 Unpack the source tarball, and change the current directory to the
5991 extracted source tree. If the source is actually a directory, copy it
5992 to the build tree, and enter that directory.
5994 @item patch-source-shebangs
5995 Patch shebangs encountered in source files so they refer to the right
5996 store file names. For instance, this changes @code{#!/bin/sh} to
5997 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
6000 Run the @file{configure} script with a number of default options, such
6001 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
6002 by the @code{#:configure-flags} argument.
6005 Run @code{make} with the list of flags specified with
6006 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
6007 (the default), build with @code{make -j}.
6010 Run @code{make check}, or some other target specified with
6011 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
6012 @code{#:parallel-tests?} argument is true (the default), run @code{make
6016 Run @code{make install} with the flags listed in @code{#:make-flags}.
6018 @item patch-shebangs
6019 Patch shebangs on the installed executable files.
6022 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
6023 is false), copying them to the @code{debug} output when available
6024 (@pxref{Installing Debugging Files}).
6027 @vindex %standard-phases
6028 The build-side module @code{(guix build gnu-build-system)} defines
6029 @code{%standard-phases} as the default list of build phases.
6030 @code{%standard-phases} is a list of symbol/procedure pairs, where the
6031 procedure implements the actual phase.
6033 The list of phases used for a particular package can be changed with the
6034 @code{#:phases} parameter. For instance, passing:
6037 #:phases (modify-phases %standard-phases (delete 'configure))
6040 means that all the phases described above will be used, except the
6041 @code{configure} phase.
6043 In addition, this build system ensures that the ``standard'' environment
6044 for GNU packages is available. This includes tools such as GCC, libc,
6045 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
6046 build-system gnu)} module for a complete list). We call these the
6047 @dfn{implicit inputs} of a package, because package definitions do not
6048 have to mention them.
6051 Other @code{<build-system>} objects are defined to support other
6052 conventions and tools used by free software packages. They inherit most
6053 of @code{gnu-build-system}, and differ mainly in the set of inputs
6054 implicitly added to the build process, and in the list of phases
6055 executed. Some of these build systems are listed below.
6057 @defvr {Scheme Variable} ant-build-system
6058 This variable is exported by @code{(guix build-system ant)}. It
6059 implements the build procedure for Java packages that can be built with
6060 @url{https://ant.apache.org/, Ant build tool}.
6062 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
6063 provided by the @code{icedtea} package to the set of inputs. Different
6064 packages can be specified with the @code{#:ant} and @code{#:jdk}
6065 parameters, respectively.
6067 When the original package does not provide a suitable Ant build file,
6068 the parameter @code{#:jar-name} can be used to generate a minimal Ant
6069 build file @file{build.xml} with tasks to build the specified jar
6070 archive. In this case the parameter @code{#:source-dir} can be used to
6071 specify the source sub-directory, defaulting to ``src''.
6073 The @code{#:main-class} parameter can be used with the minimal ant
6074 buildfile to specify the main class of the resulting jar. This makes the
6075 jar file executable. The @code{#:test-include} parameter can be used to
6076 specify the list of junit tests to run. It defaults to
6077 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
6078 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
6079 because abstract classes cannot be run as tests.
6081 The parameter @code{#:build-target} can be used to specify the Ant task
6082 that should be run during the @code{build} phase. By default the
6083 ``jar'' task will be run.
6087 @defvr {Scheme Variable} android-ndk-build-system
6088 @cindex Android distribution
6089 @cindex Android NDK build system
6090 This variable is exported by @code{(guix build-system android-ndk)}. It
6091 implements a build procedure for Android NDK (native development kit)
6092 packages using a Guix-specific build process.
6094 The build system assumes that packages install their public interface
6095 (header) files to the subdirectory "include" of the "out" output and
6096 their libraries to the subdirectory "lib" of the "out" output.
6098 It's also assumed that the union of all the dependencies of a package
6099 has no conflicting files.
6101 For the time being, cross-compilation is not supported - so right now
6102 the libraries and header files are assumed to be host tools.
6106 @defvr {Scheme Variable} asdf-build-system/source
6107 @defvrx {Scheme Variable} asdf-build-system/sbcl
6108 @defvrx {Scheme Variable} asdf-build-system/ecl
6110 These variables, exported by @code{(guix build-system asdf)}, implement
6111 build procedures for Common Lisp packages using
6112 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
6113 definition facility for Common Lisp programs and libraries.
6115 The @code{asdf-build-system/source} system installs the packages in
6116 source form, and can be loaded using any common lisp implementation, via
6117 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
6118 systems in the format which a particular implementation understands.
6119 These build systems can also be used to produce executable programs, or
6120 lisp images which contain a set of packages pre-loaded.
6122 The build system uses naming conventions. For binary packages, the
6123 package name should be prefixed with the lisp implementation, such as
6124 @code{sbcl-} for @code{asdf-build-system/sbcl}.
6126 Additionally, the corresponding source package should be labeled using
6127 the same convention as python packages (see @ref{Python Modules}), using
6128 the @code{cl-} prefix.
6130 For binary packages, each system should be defined as a Guix package.
6131 If one package @code{origin} contains several systems, package variants
6132 can be created in order to build all the systems. Source packages,
6133 which use @code{asdf-build-system/source}, may contain several systems.
6135 In order to create executable programs and images, the build-side
6136 procedures @code{build-program} and @code{build-image} can be used.
6137 They should be called in a build phase after the @code{create-symlinks}
6138 phase, so that the system which was just built can be used within the
6139 resulting image. @code{build-program} requires a list of Common Lisp
6140 expressions to be passed as the @code{#:entry-program} argument.
6142 If the system is not defined within its own @code{.asd} file of the same
6143 name, then the @code{#:asd-file} parameter should be used to specify
6144 which file the system is defined in. Furthermore, if the package
6145 defines a system for its tests in a separate file, it will be loaded
6146 before the tests are run if it is specified by the
6147 @code{#:test-asd-file} parameter. If it is not set, the files
6148 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
6149 and @code{test.asd} will be tried if they exist.
6151 If for some reason the package must be named in a different way than the
6152 naming conventions suggest, the @code{#:asd-system-name} parameter can
6153 be used to specify the name of the system.
6157 @defvr {Scheme Variable} cargo-build-system
6158 @cindex Rust programming language
6159 @cindex Cargo (Rust build system)
6160 This variable is exported by @code{(guix build-system cargo)}. It
6161 supports builds of packages using Cargo, the build tool of the
6162 @uref{https://www.rust-lang.org, Rust programming language}.
6164 It adds @code{rustc} and @code{cargo} to the set of inputs.
6165 A different Rust package can be specified with the @code{#:rust} parameter.
6167 Regular cargo dependencies should be added to the package definition via the
6168 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
6169 spec can be a package or a source definition. Note that the spec must
6170 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
6171 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
6172 should be added to the package definition via the
6173 @code{#:cargo-development-inputs} parameter.
6175 In its @code{configure} phase, this build system will make any source inputs
6176 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6177 parameters available to cargo. It will also remove an included
6178 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6179 @code{build} phase. The @code{install} phase installs any crate the binaries
6180 if they are defined by the crate.
6184 @defvr {Scheme Variable} copy-build-system
6185 This variable is exported by @code{(guix build-system copy)}. It
6186 supports builds of simple packages that don't require much compiling,
6187 mostly just moving files around.
6189 It adds much of the @code{gnu-build-system} packages to the set of
6190 inputs. Because of this, the @code{copy-build-system} does not require
6191 all the boilerplate code often needed for the
6192 @code{trivial-build-system}.
6194 To further simplify the file installation process, an
6195 @code{#:install-plan} argument is exposed to let the packager specify
6196 which files go where. The install plan is a list of @code{(@var{source}
6197 @var{target} [@var{filters}])}. @var{filters} are optional.
6200 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
6202 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
6203 @item Otherwise install @var{source} as @var{target}.
6206 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
6207 the trailing slash of @var{target} is implied with the same meaning
6210 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
6211 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
6212 @code{#:exclude-regexp}, only select files are installed depending on
6213 the filters. Each filters is specified by a list of strings.
6215 @item With @code{#:include}, install all the files which the path suffix matches
6216 at least one of the elements in the given list.
6217 @item With @code{#:include-regexp}, install all the files which the
6218 subpaths match at least one of the regular expressions in the given
6220 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
6221 are the complement of their inclusion counterpart. Without @code{#:include} flags,
6222 install all files but those matching the exclusion filters.
6223 If both inclusions and exclusions are specified, the exclusions are done
6224 on top of the inclusions.
6227 In all cases, the paths relative to @var{source} are preserved within
6234 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
6235 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
6236 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
6237 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
6238 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
6239 @file{share/my-app/sub/file}.
6240 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
6241 @file{share/my-app/file}.
6246 @cindex Clojure (programming language)
6247 @cindex simple Clojure build system
6248 @defvr {Scheme Variable} clojure-build-system
6249 This variable is exported by @code{(guix build-system clojure)}. It implements
6250 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6251 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6254 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6255 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6256 @code{#:zip} parameters, respectively.
6258 A list of source directories, test directories and jar names can be specified
6259 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6260 parameters, respectively. Compile directory and main class can be specified
6261 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6262 Other parameters are documented below.
6264 This build system is an extension of @code{ant-build-system}, but with the
6265 following phases changed:
6270 This phase calls @code{compile} in Clojure to compile source files and runs
6271 @command{jar} to create jars from both source files and compiled files
6272 according to the include list and exclude list specified in
6273 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6274 has priority over the include list. These lists consist of symbols
6275 representing Clojure libraries or the special keyword @code{#:all} representing
6276 all Clojure libraries found under the source directories. The parameter
6277 @code{#:omit-source?} decides if source should be included into the jars.
6280 This phase runs tests according to the include list and exclude list specified
6281 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6282 meanings are analogous to that of @code{#:aot-include} and
6283 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6284 stands for all Clojure libraries found under the test directories. The
6285 parameter @code{#:tests?} decides if tests should be run.
6288 This phase installs all jars built previously.
6291 Apart from the above, this build system also contains an additional phase:
6296 This phase installs all top-level files with base name matching
6297 @code{%doc-regex}. A different regex can be specified with the
6298 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6299 directories specified in @code{#:doc-dirs} are installed as well.
6303 @defvr {Scheme Variable} cmake-build-system
6304 This variable is exported by @code{(guix build-system cmake)}. It
6305 implements the build procedure for packages using the
6306 @url{https://www.cmake.org, CMake build tool}.
6308 It automatically adds the @code{cmake} package to the set of inputs.
6309 Which package is used can be specified with the @code{#:cmake}
6312 The @code{#:configure-flags} parameter is taken as a list of flags
6313 passed to the @command{cmake} command. The @code{#:build-type}
6314 parameter specifies in abstract terms the flags passed to the compiler;
6315 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6316 debugging information''), which roughly means that code is compiled with
6317 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6320 @defvr {Scheme Variable} dune-build-system
6321 This variable is exported by @code{(guix build-system dune)}. It
6322 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6323 tool for the OCaml programming language. It is implemented as an extension
6324 of the @code{ocaml-build-system} which is described below. As such, the
6325 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6328 It automatically adds the @code{dune} package to the set of inputs.
6329 Which package is used can be specified with the @code{#:dune}
6332 There is no @code{configure} phase because dune packages typically don't
6333 need to be configured. The @code{#:build-flags} parameter is taken as a
6334 list of flags passed to the @code{dune} command during the build.
6336 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6337 command instead of the more recent @code{dune} command while building
6338 a package. Its default value is @code{#f}.
6340 The @code{#:package} parameter can be passed to specify a package name, which
6341 is useful when a package contains multiple packages and you want to build
6342 only one of them. This is equivalent to passing the @code{-p} argument to
6346 @defvr {Scheme Variable} go-build-system
6347 This variable is exported by @code{(guix build-system go)}. It
6348 implements a build procedure for Go packages using the standard
6349 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6350 Go build mechanisms}.
6352 The user is expected to provide a value for the key @code{#:import-path}
6353 and, in some cases, @code{#:unpack-path}. The
6354 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6355 corresponds to the file system path expected by the package's build
6356 scripts and any referring packages, and provides a unique way to
6357 refer to a Go package. It is typically based on a combination of the
6358 package source code's remote URI and file system hierarchy structure. In
6359 some cases, you will need to unpack the package's source code to a
6360 different directory structure than the one indicated by the import path,
6361 and @code{#:unpack-path} should be used in such cases.
6363 Packages that provide Go libraries should install their source code into
6364 the built output. The key @code{#:install-source?}, which defaults to
6365 @code{#t}, controls whether or not the source code is installed. It can
6366 be set to @code{#f} for packages that only provide executable files.
6369 @defvr {Scheme Variable} glib-or-gtk-build-system
6370 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6371 is intended for use with packages making use of GLib or GTK+.
6373 This build system adds the following two phases to the ones defined by
6374 @code{gnu-build-system}:
6377 @item glib-or-gtk-wrap
6378 The phase @code{glib-or-gtk-wrap} ensures that programs in
6379 @file{bin/} are able to find GLib ``schemas'' and
6380 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6381 modules}. This is achieved by wrapping the programs in launch scripts
6382 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
6383 environment variables.
6385 It is possible to exclude specific package outputs from that wrapping
6386 process by listing their names in the
6387 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6388 when an output is known not to contain any GLib or GTK+ binaries, and
6389 where wrapping would gratuitously add a dependency of that output on
6392 @item glib-or-gtk-compile-schemas
6393 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6394 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6395 GSettings schemas} of GLib are compiled. Compilation is performed by the
6396 @command{glib-compile-schemas} program. It is provided by the package
6397 @code{glib:bin} which is automatically imported by the build system.
6398 The @code{glib} package providing @command{glib-compile-schemas} can be
6399 specified with the @code{#:glib} parameter.
6402 Both phases are executed after the @code{install} phase.
6405 @defvr {Scheme Variable} guile-build-system
6406 This build system is for Guile packages that consist exclusively of Scheme
6407 code and that are so lean that they don't even have a makefile, let alone a
6408 @file{configure} script. It compiles Scheme code using @command{guild
6409 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6410 installs the @file{.scm} and @file{.go} files in the right place. It also
6411 installs documentation.
6413 This build system supports cross-compilation by using the @code{--target}
6414 option of @command{guild compile}.
6416 Packages built with @code{guile-build-system} must provide a Guile package in
6417 their @code{native-inputs} field.
6420 @defvr {Scheme Variable} julia-build-system
6421 This variable is exported by @code{(guix build-system julia)}. It implements
6422 the build procedure used by @uref{https://julialang.org/, julia} packages,
6423 which essentially is similar to running @command{julia -e 'using Pkg;
6424 Pkg.add(package)'} in an environment where @code{JULIA_LOAD_PATH} contains the
6425 paths to all Julia package inputs. Tests are run not run.
6427 Julia packages require the source @code{file-name} to be the real name of the
6428 package, correctly capitalized.
6430 For packages requiring shared library dependencies, you may need to write the
6431 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6432 variable = /gnu/store/library.so} for each dependency, plus a void function
6433 @code{check_deps() = nothing}.
6435 Some older packages that aren't using @file{Package.toml} yet, will require
6436 this file to be created, too. The function @code{julia-create-package-toml}
6437 helps creating the file. You need to pass the outputs and the source of the
6438 package, it's name (the same as the @code{file-name} parameter), the package
6439 uuid, the package version, and a list of dependencies specified by their name
6443 @defvr {Scheme Variable} minify-build-system
6444 This variable is exported by @code{(guix build-system minify)}. It
6445 implements a minification procedure for simple JavaScript packages.
6447 It adds @code{uglify-js} to the set of inputs and uses it to compress
6448 all JavaScript files in the @file{src} directory. A different minifier
6449 package can be specified with the @code{#:uglify-js} parameter, but it
6450 is expected that the package writes the minified code to the standard
6453 When the input JavaScript files are not all located in the @file{src}
6454 directory, the parameter @code{#:javascript-files} can be used to
6455 specify a list of file names to feed to the minifier.
6458 @defvr {Scheme Variable} ocaml-build-system
6459 This variable is exported by @code{(guix build-system ocaml)}. It implements
6460 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6461 of choosing the correct set of commands to run for each package. OCaml
6462 packages can expect many different commands to be run. This build system will
6465 When the package has a @file{setup.ml} file present at the top-level, it will
6466 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6467 @code{ocaml setup.ml -install}. The build system will assume that this file
6468 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6469 care of setting the prefix and enabling tests if they are not disabled. You
6470 can pass configure and build flags with the @code{#:configure-flags} and
6471 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6472 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6473 bypass this system in the build and install phases.
6475 When the package has a @file{configure} file, it is assumed that it is a
6476 hand-made configure script that requires a different argument format than
6477 in the @code{gnu-build-system}. You can add more flags with the
6478 @code{#:configure-flags} key.
6480 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6481 @code{#t}), it will be used and more flags can be passed to the build and
6482 install phases with the @code{#:make-flags} key.
6484 Finally, some packages do not have these files and use a somewhat standard
6485 location for its build system. In that case, the build system will run
6486 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6487 providing the path to the required findlib module. Additional flags can
6488 be passed via the @code{#:build-flags} key. Install is taken care of by
6489 @command{opam-installer}. In this case, the @code{opam} package must
6490 be added to the @code{native-inputs} field of the package definition.
6492 Note that most OCaml packages assume they will be installed in the same
6493 directory as OCaml, which is not what we want in guix. In particular, they
6494 will install @file{.so} files in their module's directory, which is usually
6495 fine because it is in the OCaml compiler directory. In guix though, these
6496 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6497 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6498 @file{.so} libraries should be installed.
6501 @defvr {Scheme Variable} python-build-system
6502 This variable is exported by @code{(guix build-system python)}. It
6503 implements the more or less standard build procedure used by Python
6504 packages, which consists in running @code{python setup.py build} and
6505 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6507 For packages that install stand-alone Python programs under @code{bin/},
6508 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6509 environment variable points to all the Python libraries they depend on.
6511 Which Python package is used to perform the build can be specified with
6512 the @code{#:python} parameter. This is a useful way to force a package
6513 to be built for a specific version of the Python interpreter, which
6514 might be necessary if the package is only compatible with a single
6515 interpreter version.
6517 By default guix calls @code{setup.py} under control of
6518 @code{setuptools}, much like @command{pip} does. Some packages are not
6519 compatible with setuptools (and pip), thus you can disable this by
6520 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6523 @defvr {Scheme Variable} perl-build-system
6524 This variable is exported by @code{(guix build-system perl)}. It
6525 implements the standard build procedure for Perl packages, which either
6526 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6527 followed by @code{Build} and @code{Build install}; or in running
6528 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6529 @code{make} and @code{make install}, depending on which of
6530 @code{Build.PL} or @code{Makefile.PL} is present in the package
6531 distribution. Preference is given to the former if both @code{Build.PL}
6532 and @code{Makefile.PL} exist in the package distribution. This
6533 preference can be reversed by specifying @code{#t} for the
6534 @code{#:make-maker?} parameter.
6536 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6537 passes flags specified by the @code{#:make-maker-flags} or
6538 @code{#:module-build-flags} parameter, respectively.
6540 Which Perl package is used can be specified with @code{#:perl}.
6543 @defvr {Scheme Variable} qt-build-system
6544 This variable is exported by @code{(guix build-system qt)}. It
6545 is intended for use with applications using Qt or KDE.
6547 This build system adds the following two phases to the ones defined by
6548 @code{cmake-build-system}:
6552 The phase @code{check-setup} prepares the environment for running
6553 the checks as commonly used by Qt test programs.
6554 For now this only sets some environment variables:
6555 @code{QT_QPA_PLATFORM=offscreen},
6556 @code{DBUS_FATAL_WARNINGS=0} and
6557 @code{CTEST_OUTPUT_ON_FAILURE=1}.
6559 This phase is added before the @code{check} phase.
6560 It's a separate phase to ease adjusting if necessary.
6563 The phase @code{qt-wrap}
6564 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
6565 and output. In case some path is found, all programs in the output's
6566 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
6567 are wrapped in scripts defining the necessary environment variables.
6569 It is possible to exclude specific package outputs from that wrapping process
6570 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
6571 This is useful when an output is known not to contain any Qt binaries, and
6572 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
6575 This phase is added after the @code{install} phase.
6579 @defvr {Scheme Variable} r-build-system
6580 This variable is exported by @code{(guix build-system r)}. It
6581 implements the build procedure used by @uref{https://r-project.org, R}
6582 packages, which essentially is little more than running @code{R CMD
6583 INSTALL --library=/gnu/store/@dots{}} in an environment where
6584 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6585 are run after installation using the R function
6586 @code{tools::testInstalledPackage}.
6589 @defvr {Scheme Variable} rakudo-build-system
6590 This variable is exported by @code{(guix build-system rakudo)}. It
6591 implements the build procedure used by @uref{https://rakudo.org/,
6592 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6593 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6594 installs the binaries, library files and the resources, as well as wrap
6595 the files under the @code{bin/} directory. Tests can be skipped by
6596 passing @code{#f} to the @code{tests?} parameter.
6598 Which rakudo package is used can be specified with @code{rakudo}.
6599 Which perl6-tap-harness package used for the tests can be specified with
6600 @code{#:prove6} or removed by passing @code{#f} to the
6601 @code{with-prove6?} parameter.
6602 Which perl6-zef package used for tests and installing can be specified
6603 with @code{#:zef} or removed by passing @code{#f} to the
6604 @code{with-zef?} parameter.
6607 @defvr {Scheme Variable} texlive-build-system
6608 This variable is exported by @code{(guix build-system texlive)}. It is
6609 used to build TeX packages in batch mode with a specified engine. The
6610 build system sets the @code{TEXINPUTS} variable to find all TeX source
6611 files in the inputs.
6613 By default it runs @code{luatex} on all files ending on @code{ins}. A
6614 different engine and format can be specified with the
6615 @code{#:tex-format} argument. Different build targets can be specified
6616 with the @code{#:build-targets} argument, which expects a list of file
6617 names. The build system adds only @code{texlive-bin} and
6618 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6619 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6620 and @code{#:texlive-latex-base}, respectively.
6622 The @code{#:tex-directory} parameter tells the build system where to
6623 install the built files under the texmf tree.
6626 @defvr {Scheme Variable} ruby-build-system
6627 This variable is exported by @code{(guix build-system ruby)}. It
6628 implements the RubyGems build procedure used by Ruby packages, which
6629 involves running @code{gem build} followed by @code{gem install}.
6631 The @code{source} field of a package that uses this build system
6632 typically references a gem archive, since this is the format that Ruby
6633 developers use when releasing their software. The build system unpacks
6634 the gem archive, potentially patches the source, runs the test suite,
6635 repackages the gem, and installs it. Additionally, directories and
6636 tarballs may be referenced to allow building unreleased gems from Git or
6637 a traditional source release tarball.
6639 Which Ruby package is used can be specified with the @code{#:ruby}
6640 parameter. A list of additional flags to be passed to the @command{gem}
6641 command can be specified with the @code{#:gem-flags} parameter.
6644 @defvr {Scheme Variable} waf-build-system
6645 This variable is exported by @code{(guix build-system waf)}. It
6646 implements a build procedure around the @code{waf} script. The common
6647 phases---@code{configure}, @code{build}, and @code{install}---are
6648 implemented by passing their names as arguments to the @code{waf}
6651 The @code{waf} script is executed by the Python interpreter. Which
6652 Python package is used to run the script can be specified with the
6653 @code{#:python} parameter.
6656 @defvr {Scheme Variable} scons-build-system
6657 This variable is exported by @code{(guix build-system scons)}. It
6658 implements the build procedure used by the SCons software construction
6659 tool. This build system runs @code{scons} to build the package,
6660 @code{scons test} to run tests, and then @code{scons install} to install
6663 Additional flags to be passed to @code{scons} can be specified with the
6664 @code{#:scons-flags} parameter. The default build and install targets
6665 can be overridden with @code{#:build-targets} and
6666 @code{#:install-targets} respectively. The version of Python used to
6667 run SCons can be specified by selecting the appropriate SCons package
6668 with the @code{#:scons} parameter.
6671 @defvr {Scheme Variable} haskell-build-system
6672 This variable is exported by @code{(guix build-system haskell)}. It
6673 implements the Cabal build procedure used by Haskell packages, which
6674 involves running @code{runhaskell Setup.hs configure
6675 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6676 Instead of installing the package by running @code{runhaskell Setup.hs
6677 install}, to avoid trying to register libraries in the read-only
6678 compiler store directory, the build system uses @code{runhaskell
6679 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6680 addition, the build system generates the package documentation by
6681 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6682 is passed. Optional Haddock parameters can be passed with the help of
6683 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6684 not found, the build system looks for @code{Setup.lhs} instead.
6686 Which Haskell compiler is used can be specified with the @code{#:haskell}
6687 parameter which defaults to @code{ghc}.
6690 @defvr {Scheme Variable} dub-build-system
6691 This variable is exported by @code{(guix build-system dub)}. It
6692 implements the Dub build procedure used by D packages, which
6693 involves running @code{dub build} and @code{dub run}.
6694 Installation is done by copying the files manually.
6696 Which D compiler is used can be specified with the @code{#:ldc}
6697 parameter which defaults to @code{ldc}.
6700 @defvr {Scheme Variable} emacs-build-system
6701 This variable is exported by @code{(guix build-system emacs)}. It
6702 implements an installation procedure similar to the packaging system
6703 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6705 It first creates the @code{@code{package}-autoloads.el} file, then it
6706 byte compiles all Emacs Lisp files. Differently from the Emacs
6707 packaging system, the Info documentation files are moved to the standard
6708 documentation directory and the @file{dir} file is deleted. The Elisp
6709 package files are installed directly under @file{share/emacs/site-lisp}.
6712 @defvr {Scheme Variable} font-build-system
6713 This variable is exported by @code{(guix build-system font)}. It
6714 implements an installation procedure for font packages where upstream
6715 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6716 need to be copied into place. It copies font files to standard
6717 locations in the output directory.
6720 @defvr {Scheme Variable} meson-build-system
6721 This variable is exported by @code{(guix build-system meson)}. It
6722 implements the build procedure for packages that use
6723 @url{https://mesonbuild.com, Meson} as their build system.
6725 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6726 of inputs, and they can be changed with the parameters @code{#:meson}
6727 and @code{#:ninja} if needed. The default Meson is
6728 @code{meson-for-build}, which is special because it doesn't clear the
6729 @code{RUNPATH} of binaries and libraries when they are installed.
6731 This build system is an extension of @code{gnu-build-system}, but with the
6732 following phases changed to some specific for Meson:
6737 The phase runs @code{meson} with the flags specified in
6738 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6739 @code{plain} unless something else is specified in @code{#:build-type}.
6742 The phase runs @code{ninja} to build the package in parallel by default, but
6743 this can be changed with @code{#:parallel-build?}.
6746 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6747 which is @code{"test"} by default.
6750 The phase runs @code{ninja install} and can not be changed.
6753 Apart from that, the build system also adds the following phases:
6758 This phase ensures that all binaries can find the libraries they need.
6759 It searches for required libraries in subdirectories of the package being
6760 built, and adds those to @code{RUNPATH} where needed. It also removes
6761 references to libraries left over from the build phase by
6762 @code{meson-for-build}, such as test dependencies, that aren't actually
6763 required for the program to run.
6765 @item glib-or-gtk-wrap
6766 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6767 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6769 @item glib-or-gtk-compile-schemas
6770 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6771 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6775 @defvr {Scheme Variable} linux-module-build-system
6776 @code{linux-module-build-system} allows building Linux kernel modules.
6778 @cindex build phases
6779 This build system is an extension of @code{gnu-build-system}, but with the
6780 following phases changed:
6785 This phase configures the environment so that the Linux kernel's Makefile
6786 can be used to build the external kernel module.
6789 This phase uses the Linux kernel's Makefile in order to build the external
6793 This phase uses the Linux kernel's Makefile in order to install the external
6797 It is possible and useful to specify the Linux kernel to use for building
6798 the module (in the "arguments" form of a package using the
6799 linux-module-build-system, use the key #:linux to specify it).
6802 @defvr {Scheme Variable} node-build-system
6803 This variable is exported by @code{(guix build-system node)}. It
6804 implements the build procedure used by @uref{https://nodejs.org,
6805 Node.js}, which implements an approximation of the @code{npm install}
6806 command, followed by an @code{npm test} command.
6808 Which Node.js package is used to interpret the @code{npm} commands can
6809 be specified with the @code{#:node} parameter which defaults to
6813 Lastly, for packages that do not need anything as sophisticated, a
6814 ``trivial'' build system is provided. It is trivial in the sense that
6815 it provides basically no support: it does not pull any implicit inputs,
6816 and does not have a notion of build phases.
6818 @defvr {Scheme Variable} trivial-build-system
6819 This variable is exported by @code{(guix build-system trivial)}.
6821 This build system requires a @code{#:builder} argument. This argument
6822 must be a Scheme expression that builds the package output(s)---as
6823 with @code{build-expression->derivation} (@pxref{Derivations,
6824 @code{build-expression->derivation}}).
6834 Conceptually, the @dfn{store} is the place where derivations that have
6835 been built successfully are stored---by default, @file{/gnu/store}.
6836 Sub-directories in the store are referred to as @dfn{store items} or
6837 sometimes @dfn{store paths}. The store has an associated database that
6838 contains information such as the store paths referred to by each store
6839 path, and the list of @emph{valid} store items---results of successful
6840 builds. This database resides in @file{@var{localstatedir}/guix/db},
6841 where @var{localstatedir} is the state directory specified @i{via}
6842 @option{--localstatedir} at configure time, usually @file{/var}.
6844 The store is @emph{always} accessed by the daemon on behalf of its clients
6845 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6846 connect to the daemon over a Unix-domain socket, send requests to it,
6847 and read the result---these are remote procedure calls, or RPCs.
6850 Users must @emph{never} modify files under @file{/gnu/store} directly.
6851 This would lead to inconsistencies and break the immutability
6852 assumptions of Guix's functional model (@pxref{Introduction}).
6854 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6855 how to check the integrity of the store and attempt recovery from
6856 accidental modifications.
6859 The @code{(guix store)} module provides procedures to connect to the
6860 daemon, and to perform RPCs. These are described below. By default,
6861 @code{open-connection}, and thus all the @command{guix} commands,
6862 connect to the local daemon or to the URI specified by the
6863 @code{GUIX_DAEMON_SOCKET} environment variable.
6865 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6866 When set, the value of this variable should be a file name or a URI
6867 designating the daemon endpoint. When it is a file name, it denotes a
6868 Unix-domain socket to connect to. In addition to file names, the
6869 supported URI schemes are:
6874 These are for Unix-domain sockets.
6875 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6876 @file{/var/guix/daemon-socket/socket}.
6879 @cindex daemon, remote access
6880 @cindex remote access to the daemon
6881 @cindex daemon, cluster setup
6882 @cindex clusters, daemon setup
6883 These URIs denote connections over TCP/IP, without encryption nor
6884 authentication of the remote host. The URI must specify the host name
6885 and optionally a port number (by default port 44146 is used):
6888 guix://master.guix.example.org:1234
6891 This setup is suitable on local networks, such as clusters, where only
6892 trusted nodes may connect to the build daemon at
6893 @code{master.guix.example.org}.
6895 The @code{--listen} option of @command{guix-daemon} can be used to
6896 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6900 @cindex SSH access to build daemons
6901 These URIs allow you to connect to a remote daemon over SSH. This
6902 feature requires Guile-SSH (@pxref{Requirements}) and a working
6903 @code{guile} binary in @code{PATH} on the destination machine. It
6904 supports public key and GSSAPI authentication. A typical URL might look
6908 ssh://charlie@@guix.example.org:22
6911 As for @command{guix copy}, the usual OpenSSH client configuration files
6912 are honored (@pxref{Invoking guix copy}).
6915 Additional URI schemes may be supported in the future.
6917 @c XXX: Remove this note when the protocol incurs fewer round trips
6918 @c and when (guix derivations) no longer relies on file system access.
6920 The ability to connect to remote build daemons is considered
6921 experimental as of @value{VERSION}. Please get in touch with us to
6922 share any problems or suggestions you may have (@pxref{Contributing}).
6926 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6927 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6928 @var{reserve-space?} is true, instruct it to reserve a little bit of
6929 extra space on the file system so that the garbage collector can still
6930 operate should the disk become full. Return a server object.
6932 @var{file} defaults to @code{%default-socket-path}, which is the normal
6933 location given the options that were passed to @command{configure}.
6936 @deffn {Scheme Procedure} close-connection @var{server}
6937 Close the connection to @var{server}.
6940 @defvr {Scheme Variable} current-build-output-port
6941 This variable is bound to a SRFI-39 parameter, which refers to the port
6942 where build and error logs sent by the daemon should be written.
6945 Procedures that make RPCs all take a server object as their first
6948 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6949 @cindex invalid store items
6950 Return @code{#t} when @var{path} designates a valid store item and
6951 @code{#f} otherwise (an invalid item may exist on disk but still be
6952 invalid, for instance because it is the result of an aborted or failed
6955 A @code{&store-protocol-error} condition is raised if @var{path} is not
6956 prefixed by the store directory (@file{/gnu/store}).
6959 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6960 Add @var{text} under file @var{name} in the store, and return its store
6961 path. @var{references} is the list of store paths referred to by the
6962 resulting store path.
6965 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6967 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6968 file names, or derivation/output pairs, using the specified
6969 @var{mode}---@code{(build-mode normal)} by default.
6972 Note that the @code{(guix monads)} module provides a monad as well as
6973 monadic versions of the above procedures, with the goal of making it
6974 more convenient to work with code that accesses the store (@pxref{The
6978 @i{This section is currently incomplete.}
6981 @section Derivations
6984 Low-level build actions and the environment in which they are performed
6985 are represented by @dfn{derivations}. A derivation contains the
6986 following pieces of information:
6990 The outputs of the derivation---derivations produce at least one file or
6991 directory in the store, but may produce more.
6994 @cindex build-time dependencies
6995 @cindex dependencies, build-time
6996 The inputs of the derivations---i.e., its build-time dependencies---which may
6997 be other derivations or plain files in the store (patches, build scripts,
7001 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
7004 The file name of a build script in the store, along with the arguments
7008 A list of environment variables to be defined.
7012 @cindex derivation path
7013 Derivations allow clients of the daemon to communicate build actions to
7014 the store. They exist in two forms: as an in-memory representation,
7015 both on the client- and daemon-side, and as files in the store whose
7016 name end in @code{.drv}---these files are referred to as @dfn{derivation
7017 paths}. Derivations paths can be passed to the @code{build-derivations}
7018 procedure to perform the build actions they prescribe (@pxref{The
7021 @cindex fixed-output derivations
7022 Operations such as file downloads and version-control checkouts for
7023 which the expected content hash is known in advance are modeled as
7024 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
7025 of a fixed-output derivation are independent of its inputs---e.g., a
7026 source code download produces the same result regardless of the download
7027 method and tools being used.
7030 @cindex run-time dependencies
7031 @cindex dependencies, run-time
7032 The outputs of derivations---i.e., the build results---have a set of
7033 @dfn{references}, as reported by the @code{references} RPC or the
7034 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
7035 are the set of run-time dependencies of the build results. References are a
7036 subset of the inputs of the derivation; this subset is automatically computed
7037 by the build daemon by scanning all the files in the outputs.
7039 The @code{(guix derivations)} module provides a representation of
7040 derivations as Scheme objects, along with procedures to create and
7041 otherwise manipulate derivations. The lowest-level primitive to create
7042 a derivation is the @code{derivation} procedure:
7044 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
7045 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7046 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
7047 [#:system (%current-system)] [#:references-graphs #f] @
7048 [#:allowed-references #f] [#:disallowed-references #f] @
7049 [#:leaked-env-vars #f] [#:local-build? #f] @
7050 [#:substitutable? #t] [#:properties '()]
7051 Build a derivation with the given arguments, and return the resulting
7052 @code{<derivation>} object.
7054 When @var{hash} and @var{hash-algo} are given, a
7055 @dfn{fixed-output derivation} is created---i.e., one whose result is
7056 known in advance, such as a file download. If, in addition,
7057 @var{recursive?} is true, then that fixed output may be an executable
7058 file or a directory and @var{hash} must be the hash of an archive
7059 containing this output.
7061 When @var{references-graphs} is true, it must be a list of file
7062 name/store path pairs. In that case, the reference graph of each store
7063 path is exported in the build environment in the corresponding file, in
7064 a simple text format.
7066 When @var{allowed-references} is true, it must be a list of store items
7067 or outputs that the derivation's output may refer to. Likewise,
7068 @var{disallowed-references}, if true, must be a list of things the
7069 outputs may @emph{not} refer to.
7071 When @var{leaked-env-vars} is true, it must be a list of strings
7072 denoting environment variables that are allowed to ``leak'' from the
7073 daemon's environment to the build environment. This is only applicable
7074 to fixed-output derivations---i.e., when @var{hash} is true. The main
7075 use is to allow variables such as @code{http_proxy} to be passed to
7076 derivations that download files.
7078 When @var{local-build?} is true, declare that the derivation is not a
7079 good candidate for offloading and should rather be built locally
7080 (@pxref{Daemon Offload Setup}). This is the case for small derivations
7081 where the costs of data transfers would outweigh the benefits.
7083 When @var{substitutable?} is false, declare that substitutes of the
7084 derivation's output should not be used (@pxref{Substitutes}). This is
7085 useful, for instance, when building packages that capture details of the
7086 host CPU instruction set.
7088 @var{properties} must be an association list describing ``properties'' of the
7089 derivation. It is kept as-is, uninterpreted, in the derivation.
7093 Here's an example with a shell script as its builder, assuming
7094 @var{store} is an open connection to the daemon, and @var{bash} points
7095 to a Bash executable in the store:
7098 (use-modules (guix utils)
7102 (let ((builder ; add the Bash script to the store
7103 (add-text-to-store store "my-builder.sh"
7104 "echo hello world > $out\n" '())))
7105 (derivation store "foo"
7106 bash `("-e" ,builder)
7107 #:inputs `((,bash) (,builder))
7108 #:env-vars '(("HOME" . "/homeless"))))
7109 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
7112 As can be guessed, this primitive is cumbersome to use directly. A
7113 better approach is to write build scripts in Scheme, of course! The
7114 best course of action for that is to write the build code as a
7115 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
7116 information, @pxref{G-Expressions}.
7118 Once upon a time, @code{gexp->derivation} did not exist and constructing
7119 derivations with build code written in Scheme was achieved with
7120 @code{build-expression->derivation}, documented below. This procedure
7121 is now deprecated in favor of the much nicer @code{gexp->derivation}.
7123 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
7124 @var{name} @var{exp} @
7125 [#:system (%current-system)] [#:inputs '()] @
7126 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7127 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7128 [#:references-graphs #f] [#:allowed-references #f] @
7129 [#:disallowed-references #f] @
7130 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
7131 Return a derivation that executes Scheme expression @var{exp} as a
7132 builder for derivation @var{name}. @var{inputs} must be a list of
7133 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
7134 @code{"out"} is assumed. @var{modules} is a list of names of Guile
7135 modules from the current search path to be copied in the store,
7136 compiled, and made available in the load path during the execution of
7137 @var{exp}---e.g., @code{((guix build utils) (guix build
7138 gnu-build-system))}.
7140 @var{exp} is evaluated in an environment where @code{%outputs} is bound
7141 to a list of output/path pairs, and where @code{%build-inputs} is bound
7142 to a list of string/output-path pairs made from @var{inputs}.
7143 Optionally, @var{env-vars} is a list of string pairs specifying the name
7144 and value of environment variables visible to the builder. The builder
7145 terminates by passing the result of @var{exp} to @code{exit}; thus, when
7146 @var{exp} returns @code{#f}, the build is considered to have failed.
7148 @var{exp} is built using @var{guile-for-build} (a derivation). When
7149 @var{guile-for-build} is omitted or is @code{#f}, the value of the
7150 @code{%guile-for-build} fluid is used instead.
7152 See the @code{derivation} procedure for the meaning of
7153 @var{references-graphs}, @var{allowed-references},
7154 @var{disallowed-references}, @var{local-build?}, and
7155 @var{substitutable?}.
7159 Here's an example of a single-output derivation that creates a directory
7160 containing one file:
7163 (let ((builder '(let ((out (assoc-ref %outputs "out")))
7164 (mkdir out) ; create /gnu/store/@dots{}-goo
7165 (call-with-output-file (string-append out "/test")
7167 (display '(hello guix) p))))))
7168 (build-expression->derivation store "goo" builder))
7170 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
7174 @node The Store Monad
7175 @section The Store Monad
7179 The procedures that operate on the store described in the previous
7180 sections all take an open connection to the build daemon as their first
7181 argument. Although the underlying model is functional, they either have
7182 side effects or depend on the current state of the store.
7184 The former is inconvenient: the connection to the build daemon has to be
7185 carried around in all those functions, making it impossible to compose
7186 functions that do not take that parameter with functions that do. The
7187 latter can be problematic: since store operations have side effects
7188 and/or depend on external state, they have to be properly sequenced.
7190 @cindex monadic values
7191 @cindex monadic functions
7192 This is where the @code{(guix monads)} module comes in. This module
7193 provides a framework for working with @dfn{monads}, and a particularly
7194 useful monad for our uses, the @dfn{store monad}. Monads are a
7195 construct that allows two things: associating ``context'' with values
7196 (in our case, the context is the store), and building sequences of
7197 computations (here computations include accesses to the store). Values
7198 in a monad---values that carry this additional context---are called
7199 @dfn{monadic values}; procedures that return such values are called
7200 @dfn{monadic procedures}.
7202 Consider this ``normal'' procedure:
7205 (define (sh-symlink store)
7206 ;; Return a derivation that symlinks the 'bash' executable.
7207 (let* ((drv (package-derivation store bash))
7208 (out (derivation->output-path drv))
7209 (sh (string-append out "/bin/bash")))
7210 (build-expression->derivation store "sh"
7211 `(symlink ,sh %output))))
7214 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
7215 as a monadic function:
7218 (define (sh-symlink)
7219 ;; Same, but return a monadic value.
7220 (mlet %store-monad ((drv (package->derivation bash)))
7221 (gexp->derivation "sh"
7222 #~(symlink (string-append #$drv "/bin/bash")
7226 There are several things to note in the second version: the @code{store}
7227 parameter is now implicit and is ``threaded'' in the calls to the
7228 @code{package->derivation} and @code{gexp->derivation} monadic
7229 procedures, and the monadic value returned by @code{package->derivation}
7230 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
7232 As it turns out, the call to @code{package->derivation} can even be
7233 omitted since it will take place implicitly, as we will see later
7234 (@pxref{G-Expressions}):
7237 (define (sh-symlink)
7238 (gexp->derivation "sh"
7239 #~(symlink (string-append #$bash "/bin/bash")
7244 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
7245 @c for the funny quote.
7246 Calling the monadic @code{sh-symlink} has no effect. As someone once
7247 said, ``you exit a monad like you exit a building on fire: by running''.
7248 So, to exit the monad and get the desired effect, one must use
7249 @code{run-with-store}:
7252 (run-with-store (open-connection) (sh-symlink))
7253 @result{} /gnu/store/...-sh-symlink
7256 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
7257 new ``meta-commands'' to make it easier to deal with monadic procedures:
7258 @code{run-in-store}, and @code{enter-store-monad}. The former is used
7259 to ``run'' a single monadic value through the store:
7262 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
7263 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7266 The latter enters a recursive REPL, where all the return values are
7267 automatically run through the store:
7270 scheme@@(guile-user)> ,enter-store-monad
7271 store-monad@@(guile-user) [1]> (package->derivation hello)
7272 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7273 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
7274 $3 = "/gnu/store/@dots{}-foo"
7275 store-monad@@(guile-user) [1]> ,q
7276 scheme@@(guile-user)>
7280 Note that non-monadic values cannot be returned in the
7281 @code{store-monad} REPL.
7283 The main syntactic forms to deal with monads in general are provided by
7284 the @code{(guix monads)} module and are described below.
7286 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7287 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7291 @deffn {Scheme Syntax} return @var{val}
7292 Return a monadic value that encapsulates @var{val}.
7295 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7296 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7297 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7298 referred to as ``bind'', but that name denotes an unrelated procedure in
7299 Guile. Thus we use this somewhat cryptic symbol inherited from the
7300 Haskell language.}. There can be one @var{mproc} or several of them, as
7305 (with-monad %state-monad
7307 (lambda (x) (return (+ 1 x)))
7308 (lambda (x) (return (* 2 x)))))
7312 @result{} some-state
7316 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7318 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7320 Bind the variables @var{var} to the monadic values @var{mval} in
7321 @var{body}, which is a sequence of expressions. As with the bind
7322 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7323 value ``contained'' in @var{mval} and making @var{var} refer to that
7324 raw, non-monadic value within the scope of the @var{body}. The form
7325 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7326 @var{val}, as per @code{let}. The binding operations occur in sequence
7327 from left to right. The last expression of @var{body} must be a monadic
7328 expression, and its result will become the result of the @code{mlet} or
7329 @code{mlet*} when run in the @var{monad}.
7331 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7332 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7335 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7336 Bind @var{mexp} and the following monadic expressions in sequence,
7337 returning the result of the last expression. Every expression in the
7338 sequence must be a monadic expression.
7340 This is akin to @code{mlet}, except that the return values of the
7341 monadic expressions are ignored. In that sense, it is analogous to
7342 @code{begin}, but applied to monadic expressions.
7345 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7346 When @var{condition} is true, evaluate the sequence of monadic
7347 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7348 @var{condition} is false, return @code{*unspecified*} in the current
7349 monad. Every expression in the sequence must be a monadic expression.
7352 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7353 When @var{condition} is false, evaluate the sequence of monadic
7354 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7355 @var{condition} is true, return @code{*unspecified*} in the current
7356 monad. Every expression in the sequence must be a monadic expression.
7360 The @code{(guix monads)} module provides the @dfn{state monad}, which
7361 allows an additional value---the state---to be @emph{threaded} through
7362 monadic procedure calls.
7364 @defvr {Scheme Variable} %state-monad
7365 The state monad. Procedures in the state monad can access and change
7366 the state that is threaded.
7368 Consider the example below. The @code{square} procedure returns a value
7369 in the state monad. It returns the square of its argument, but also
7370 increments the current state value:
7374 (mlet %state-monad ((count (current-state)))
7375 (mbegin %state-monad
7376 (set-current-state (+ 1 count))
7379 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7384 When ``run'' through @code{%state-monad}, we obtain that additional state
7385 value, which is the number of @code{square} calls.
7388 @deffn {Monadic Procedure} current-state
7389 Return the current state as a monadic value.
7392 @deffn {Monadic Procedure} set-current-state @var{value}
7393 Set the current state to @var{value} and return the previous state as a
7397 @deffn {Monadic Procedure} state-push @var{value}
7398 Push @var{value} to the current state, which is assumed to be a list,
7399 and return the previous state as a monadic value.
7402 @deffn {Monadic Procedure} state-pop
7403 Pop a value from the current state and return it as a monadic value.
7404 The state is assumed to be a list.
7407 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7408 Run monadic value @var{mval} starting with @var{state} as the initial
7409 state. Return two values: the resulting value, and the resulting state.
7412 The main interface to the store monad, provided by the @code{(guix
7413 store)} module, is as follows.
7415 @defvr {Scheme Variable} %store-monad
7416 The store monad---an alias for @code{%state-monad}.
7418 Values in the store monad encapsulate accesses to the store. When its
7419 effect is needed, a value of the store monad must be ``evaluated'' by
7420 passing it to the @code{run-with-store} procedure (see below.)
7423 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7424 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7425 open store connection.
7428 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7429 Return as a monadic value the absolute file name in the store of the file
7430 containing @var{text}, a string. @var{references} is a list of store items that the
7431 resulting text file refers to; it defaults to the empty list.
7434 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7435 Return as a monadic value the absolute file name in the store of the file
7436 containing @var{data}, a bytevector. @var{references} is a list of store
7437 items that the resulting binary file refers to; it defaults to the empty list.
7440 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7441 [#:recursive? #t] [#:select? (const #t)]
7442 Return the name of @var{file} once interned in the store. Use
7443 @var{name} as its store name, or the basename of @var{file} if
7444 @var{name} is omitted.
7446 When @var{recursive?} is true, the contents of @var{file} are added
7447 recursively; if @var{file} designates a flat file and @var{recursive?}
7448 is true, its contents are added, and its permission bits are kept.
7450 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7451 @var{stat})} for each directory entry, where @var{file} is the entry's
7452 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7453 entries for which @var{select?} does not return true.
7455 The example below adds a file to the store, under two different names:
7458 (run-with-store (open-connection)
7459 (mlet %store-monad ((a (interned-file "README"))
7460 (b (interned-file "README" "LEGU-MIN")))
7461 (return (list a b))))
7463 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7468 The @code{(guix packages)} module exports the following package-related
7471 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7472 [#:system (%current-system)] [#:target #f] @
7475 value in the absolute file name of @var{file} within the @var{output}
7476 directory of @var{package}. When @var{file} is omitted, return the name
7477 of the @var{output} directory of @var{package}. When @var{target} is
7478 true, use it as a cross-compilation target triplet.
7481 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7482 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7483 @var{target} [@var{system}]
7484 Monadic version of @code{package-derivation} and
7485 @code{package-cross-derivation} (@pxref{Defining Packages}).
7490 @section G-Expressions
7492 @cindex G-expression
7493 @cindex build code quoting
7494 So we have ``derivations'', which represent a sequence of build actions
7495 to be performed to produce an item in the store (@pxref{Derivations}).
7496 These build actions are performed when asking the daemon to actually
7497 build the derivations; they are run by the daemon in a container
7498 (@pxref{Invoking guix-daemon}).
7500 @cindex strata of code
7501 It should come as no surprise that we like to write these build actions
7502 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7503 code@footnote{The term @dfn{stratum} in this context was coined by
7504 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7505 Kiselyov, who has written insightful
7506 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7507 on this topic}, refers to this kind of code generation as
7508 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7509 to the daemon, etc.---and the ``build code''---code that actually
7510 performs build actions, such as making directories, invoking
7511 @command{make}, etc.
7513 To describe a derivation and its build actions, one typically needs to
7514 embed build code inside host code. It boils down to manipulating build
7515 code as data, and the homoiconicity of Scheme---code has a direct
7516 representation as data---comes in handy for that. But we need more than
7517 the normal @code{quasiquote} mechanism in Scheme to construct build
7520 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7521 S-expressions adapted to build expressions. G-expressions, or
7522 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7523 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7524 @code{#$}, and @code{#$@@}), which are comparable to
7525 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7526 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7527 GNU Guile Reference Manual}). However, there are major differences:
7531 Gexps are meant to be written to a file and run or manipulated by other
7535 When a high-level object such as a package or derivation is unquoted
7536 inside a gexp, the result is as if its output file name had been
7540 Gexps carry information about the packages or derivations they refer to,
7541 and these dependencies are automatically added as inputs to the build
7542 processes that use them.
7545 @cindex lowering, of high-level objects in gexps
7546 This mechanism is not limited to package and derivation
7547 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7548 derivations or files in the store can be defined,
7549 such that these objects can also be inserted
7550 into gexps. For example, a useful type of high-level objects that can be
7551 inserted in a gexp is ``file-like objects'', which make it easy to
7552 add files to the store and to refer to them in
7553 derivations and such (see @code{local-file} and @code{plain-file}
7556 To illustrate the idea, here is an example of a gexp:
7563 (symlink (string-append #$coreutils "/bin/ls")
7567 This gexp can be passed to @code{gexp->derivation}; we obtain a
7568 derivation that builds a directory containing exactly one symlink to
7569 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7572 (gexp->derivation "the-thing" build-exp)
7575 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7576 substituted to the reference to the @var{coreutils} package in the
7577 actual build code, and @var{coreutils} is automatically made an input to
7578 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7579 output)}) is replaced by a string containing the directory name of the
7580 output of the derivation.
7582 @cindex cross compilation
7583 In a cross-compilation context, it is useful to distinguish between
7584 references to the @emph{native} build of a package---that can run on the
7585 host---versus references to cross builds of a package. To that end, the
7586 @code{#+} plays the same role as @code{#$}, but is a reference to a
7587 native package build:
7590 (gexp->derivation "vi"
7593 (mkdir (string-append #$output "/bin"))
7594 (system* (string-append #+coreutils "/bin/ln")
7596 (string-append #$emacs "/bin/emacs")
7597 (string-append #$output "/bin/vi")))
7598 #:target "mips64el-linux-gnu")
7602 In the example above, the native build of @var{coreutils} is used, so
7603 that @command{ln} can actually run on the host; but then the
7604 cross-compiled build of @var{emacs} is referenced.
7606 @cindex imported modules, for gexps
7607 @findex with-imported-modules
7608 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7609 able to use certain Guile modules from the ``host environment'' in the
7610 gexp, so those modules should be imported in the ``build environment''.
7611 The @code{with-imported-modules} form allows you to express that:
7614 (let ((build (with-imported-modules '((guix build utils))
7616 (use-modules (guix build utils))
7617 (mkdir-p (string-append #$output "/bin"))))))
7618 (gexp->derivation "empty-dir"
7621 (display "success!\n")
7626 In this example, the @code{(guix build utils)} module is automatically
7627 pulled into the isolated build environment of our gexp, such that
7628 @code{(use-modules (guix build utils))} works as expected.
7630 @cindex module closure
7631 @findex source-module-closure
7632 Usually you want the @emph{closure} of the module to be imported---i.e.,
7633 the module itself and all the modules it depends on---rather than just
7634 the module; failing to do that, attempts to use the module will fail
7635 because of missing dependent modules. The @code{source-module-closure}
7636 procedure computes the closure of a module by looking at its source file
7637 headers, which comes in handy in this case:
7640 (use-modules (guix modules)) ;for 'source-module-closure'
7642 (with-imported-modules (source-module-closure
7643 '((guix build utils)
7645 (gexp->derivation "something-with-vms"
7647 (use-modules (guix build utils)
7652 @cindex extensions, for gexps
7653 @findex with-extensions
7654 In the same vein, sometimes you want to import not just pure-Scheme
7655 modules, but also ``extensions'' such as Guile bindings to C libraries
7656 or other ``full-blown'' packages. Say you need the @code{guile-json}
7657 package available on the build side, here's how you would do it:
7660 (use-modules (gnu packages guile)) ;for 'guile-json'
7662 (with-extensions (list guile-json)
7663 (gexp->derivation "something-with-json"
7665 (use-modules (json))
7669 The syntactic form to construct gexps is summarized below.
7671 @deffn {Scheme Syntax} #~@var{exp}
7672 @deffnx {Scheme Syntax} (gexp @var{exp})
7673 Return a G-expression containing @var{exp}. @var{exp} may contain one
7674 or more of the following forms:
7678 @itemx (ungexp @var{obj})
7679 Introduce a reference to @var{obj}. @var{obj} may have one of the
7680 supported types, for example a package or a
7681 derivation, in which case the @code{ungexp} form is replaced by its
7682 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7684 If @var{obj} is a list, it is traversed and references to supported
7685 objects are substituted similarly.
7687 If @var{obj} is another gexp, its contents are inserted and its
7688 dependencies are added to those of the containing gexp.
7690 If @var{obj} is another kind of object, it is inserted as is.
7692 @item #$@var{obj}:@var{output}
7693 @itemx (ungexp @var{obj} @var{output})
7694 This is like the form above, but referring explicitly to the
7695 @var{output} of @var{obj}---this is useful when @var{obj} produces
7696 multiple outputs (@pxref{Packages with Multiple Outputs}).
7699 @itemx #+@var{obj}:output
7700 @itemx (ungexp-native @var{obj})
7701 @itemx (ungexp-native @var{obj} @var{output})
7702 Same as @code{ungexp}, but produces a reference to the @emph{native}
7703 build of @var{obj} when used in a cross compilation context.
7705 @item #$output[:@var{output}]
7706 @itemx (ungexp output [@var{output}])
7707 Insert a reference to derivation output @var{output}, or to the main
7708 output when @var{output} is omitted.
7710 This only makes sense for gexps passed to @code{gexp->derivation}.
7713 @itemx (ungexp-splicing @var{lst})
7714 Like the above, but splices the contents of @var{lst} inside the
7718 @itemx (ungexp-native-splicing @var{lst})
7719 Like the above, but refers to native builds of the objects listed in
7724 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7725 of the @code{gexp?} type (see below.)
7728 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7729 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7730 in their execution environment.
7732 Each item in @var{modules} can be the name of a module, such as
7733 @code{(guix build utils)}, or it can be a module name, followed by an
7734 arrow, followed by a file-like object:
7737 `((guix build utils)
7739 ((guix config) => ,(scheme-file "config.scm"
7740 #~(define-module @dots{}))))
7744 In the example above, the first two modules are taken from the search
7745 path, and the last one is created from the given file-like object.
7747 This form has @emph{lexical} scope: it has an effect on the gexps
7748 directly defined in @var{body}@dots{}, but not on those defined, say, in
7749 procedures called from @var{body}@dots{}.
7752 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7753 Mark the gexps defined in @var{body}@dots{} as requiring
7754 @var{extensions} in their build and execution environment.
7755 @var{extensions} is typically a list of package objects such as those
7756 defined in the @code{(gnu packages guile)} module.
7758 Concretely, the packages listed in @var{extensions} are added to the
7759 load path while compiling imported modules in @var{body}@dots{}; they
7760 are also added to the load path of the gexp returned by
7764 @deffn {Scheme Procedure} gexp? @var{obj}
7765 Return @code{#t} if @var{obj} is a G-expression.
7768 G-expressions are meant to be written to disk, either as code building
7769 some derivation, or as plain files in the store. The monadic procedures
7770 below allow you to do that (@pxref{The Store Monad}, for more
7771 information about monads.)
7773 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7774 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7775 [#:hash #f] [#:hash-algo #f] @
7776 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7777 [#:module-path @code{%load-path}] @
7778 [#:effective-version "2.2"] @
7779 [#:references-graphs #f] [#:allowed-references #f] @
7780 [#:disallowed-references #f] @
7781 [#:leaked-env-vars #f] @
7782 [#:script-name (string-append @var{name} "-builder")] @
7783 [#:deprecation-warnings #f] @
7784 [#:local-build? #f] [#:substitutable? #t] @
7785 [#:properties '()] [#:guile-for-build #f]
7786 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7787 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7788 stored in a file called @var{script-name}. When @var{target} is true,
7789 it is used as the cross-compilation target triplet for packages referred
7792 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7794 make @var{modules} available in the evaluation context of @var{exp};
7795 @var{modules} is a list of names of Guile modules searched in
7796 @var{module-path} to be copied in the store, compiled, and made available in
7797 the load path during the execution of @var{exp}---e.g., @code{((guix
7798 build utils) (guix build gnu-build-system))}.
7800 @var{effective-version} determines the string to use when adding extensions of
7801 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7803 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7806 When @var{references-graphs} is true, it must be a list of tuples of one of the
7810 (@var{file-name} @var{package})
7811 (@var{file-name} @var{package} @var{output})
7812 (@var{file-name} @var{derivation})
7813 (@var{file-name} @var{derivation} @var{output})
7814 (@var{file-name} @var{store-item})
7817 The right-hand-side of each element of @var{references-graphs} is automatically made
7818 an input of the build process of @var{exp}. In the build environment, each
7819 @var{file-name} contains the reference graph of the corresponding item, in a simple
7822 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7823 In the latter case, the list denotes store items that the result is allowed to
7824 refer to. Any reference to another store item will lead to a build error.
7825 Similarly for @var{disallowed-references}, which can list items that must not be
7826 referenced by the outputs.
7828 @var{deprecation-warnings} determines whether to show deprecation warnings while
7829 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7831 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7834 @cindex file-like objects
7835 The @code{local-file}, @code{plain-file}, @code{computed-file},
7836 @code{program-file}, and @code{scheme-file} procedures below return
7837 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7838 these objects lead to a file in the store. Consider this G-expression:
7841 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7842 #$(local-file "/tmp/my-nscd.conf"))
7845 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7846 to the store. Once expanded, for instance @i{via}
7847 @code{gexp->derivation}, the G-expression refers to that copy under
7848 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7849 does not have any effect on what the G-expression does.
7850 @code{plain-file} can be used similarly; it differs in that the file
7851 content is directly passed as a string.
7853 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7854 [#:recursive? #f] [#:select? (const #t)]
7855 Return an object representing local file @var{file} to add to the store;
7856 this object can be used in a gexp. If @var{file} is a literal string
7857 denoting a relative file name, it is looked up relative to the source
7858 file where it appears; if @var{file} is not a literal string, it is
7859 looked up relative to the current working directory at run time.
7860 @var{file} will be added to the store under @var{name}--by default the
7861 base name of @var{file}.
7863 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7864 designates a flat file and @var{recursive?} is true, its contents are added, and its
7865 permission bits are kept.
7867 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7868 @var{stat})} for each directory entry, where @var{file} is the entry's
7869 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7870 entries for which @var{select?} does not return true.
7872 This is the declarative counterpart of the @code{interned-file} monadic
7873 procedure (@pxref{The Store Monad, @code{interned-file}}).
7876 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7877 Return an object representing a text file called @var{name} with the given
7878 @var{content} (a string or a bytevector) to be added to the store.
7880 This is the declarative counterpart of @code{text-file}.
7883 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7884 [#:options '(#:local-build? #t)]
7885 Return an object representing the store item @var{name}, a file or
7886 directory computed by @var{gexp}. @var{options}
7887 is a list of additional arguments to pass to @code{gexp->derivation}.
7889 This is the declarative counterpart of @code{gexp->derivation}.
7892 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7893 [#:guile (default-guile)] [#:module-path %load-path] @
7894 [#:system (%current-system)] [#:target #f]
7895 Return an executable script @var{name} that runs @var{exp} using
7896 @var{guile}, with @var{exp}'s imported modules in its search path.
7897 Look up @var{exp}'s modules in @var{module-path}.
7899 The example below builds a script that simply invokes the @command{ls}
7903 (use-modules (guix gexp) (gnu packages base))
7905 (gexp->script "list-files"
7906 #~(execl #$(file-append coreutils "/bin/ls")
7910 When ``running'' it through the store (@pxref{The Store Monad,
7911 @code{run-with-store}}), we obtain a derivation that produces an
7912 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7915 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7917 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7921 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7922 [#:guile #f] [#:module-path %load-path]
7923 Return an object representing the executable store item @var{name} that
7924 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7925 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7927 This is the declarative counterpart of @code{gexp->script}.
7930 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7931 [#:set-load-path? #t] [#:module-path %load-path] @
7933 [#:guile (default-guile)]
7934 Return a derivation that builds a file @var{name} containing @var{exp}.
7935 When @var{splice?} is true, @var{exp} is considered to be a list of
7936 expressions that will be spliced in the resulting file.
7938 When @var{set-load-path?} is true, emit code in the resulting file to
7939 set @code{%load-path} and @code{%load-compiled-path} to honor
7940 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7943 The resulting file holds references to all the dependencies of @var{exp}
7944 or a subset thereof.
7947 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7948 Return an object representing the Scheme file @var{name} that contains
7951 This is the declarative counterpart of @code{gexp->file}.
7954 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7955 Return as a monadic value a derivation that builds a text file
7956 containing all of @var{text}. @var{text} may list, in addition to
7957 strings, objects of any type that can be used in a gexp: packages,
7958 derivations, local file objects, etc. The resulting store file holds
7959 references to all these.
7961 This variant should be preferred over @code{text-file} anytime the file
7962 to create will reference items from the store. This is typically the
7963 case when building a configuration file that embeds store file names,
7967 (define (profile.sh)
7968 ;; Return the name of a shell script in the store that
7969 ;; initializes the 'PATH' environment variable.
7970 (text-file* "profile.sh"
7971 "export PATH=" coreutils "/bin:"
7972 grep "/bin:" sed "/bin\n"))
7975 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7976 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7977 preventing them from being garbage-collected during its lifetime.
7980 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7981 Return an object representing store file @var{name} containing
7982 @var{text}. @var{text} is a sequence of strings and file-like objects,
7986 (mixed-text-file "profile"
7987 "export PATH=" coreutils "/bin:" grep "/bin")
7990 This is the declarative counterpart of @code{text-file*}.
7993 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7994 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7995 Each item in @var{files} must be a two-element list where the first element is the
7996 file name to use in the new directory, and the second element is a gexp
7997 denoting the target file. Here's an example:
8001 `(("hosts" ,(plain-file "hosts"
8002 "127.0.0.1 localhost"))
8003 ("bashrc" ,(plain-file "bashrc"
8004 "alias ls='ls --color=auto'"))))
8007 This yields an @code{etc} directory containing these two files.
8010 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
8011 Return a directory that is the union of @var{things}, where @var{things} is a list of
8012 file-like objects denoting directories. For example:
8015 (directory-union "guile+emacs" (list guile emacs))
8018 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
8021 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
8022 Return a file-like object that expands to the concatenation of @var{obj}
8023 and @var{suffix}, where @var{obj} is a lowerable object and each
8024 @var{suffix} is a string.
8026 As an example, consider this gexp:
8029 (gexp->script "run-uname"
8030 #~(system* #$(file-append coreutils
8034 The same effect could be achieved with:
8037 (gexp->script "run-uname"
8038 #~(system* (string-append #$coreutils
8042 There is one difference though: in the @code{file-append} case, the
8043 resulting script contains the absolute file name as a string, whereas in
8044 the second case, the resulting script contains a @code{(string-append
8045 @dots{})} expression to construct the file name @emph{at run time}.
8048 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
8049 This macro is similar to the @code{parameterize} form for
8050 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
8051 Guile Reference Manual}). The key difference is that it takes effect
8052 when the file-like object returned by @var{exp} is lowered to a
8053 derivation or store item.
8055 A typical use of @code{with-parameters} is to force the system in effect
8059 (with-parameters ((%current-system "i686-linux"))
8063 The example above returns an object that corresponds to the i686 build
8064 of Coreutils, regardless of the current value of @code{%current-system}.
8068 Of course, in addition to gexps embedded in ``host'' code, there are
8069 also modules containing build tools. To make it clear that they are
8070 meant to be used in the build stratum, these modules are kept in the
8071 @code{(guix build @dots{})} name space.
8073 @cindex lowering, of high-level objects in gexps
8074 Internally, high-level objects are @dfn{lowered}, using their compiler,
8075 to either derivations or store items. For instance, lowering a package
8076 yields a derivation, and lowering a @code{plain-file} yields a store
8077 item. This is achieved using the @code{lower-object} monadic procedure.
8079 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
8081 Return as a value in @code{%store-monad} the derivation or store item
8082 corresponding to @var{obj} for @var{system}, cross-compiling for
8083 @var{target} if @var{target} is true. @var{obj} must be an object that
8084 has an associated gexp compiler, such as a @code{<package>}.
8087 @node Invoking guix repl
8088 @section Invoking @command{guix repl}
8090 @cindex REPL, read-eval-print loop
8091 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
8092 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
8093 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
8094 command, @command{guix repl} guarantees that all the Guix modules and all its
8095 dependencies are available in the search path. You can use it this way:
8099 scheme@@(guile-user)> ,use (gnu packages base)
8100 scheme@@(guile-user)> coreutils
8101 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
8105 In addition, @command{guix repl} implements a simple machine-readable REPL
8106 protocol for use by @code{(guix inferior)}, a facility to interact with
8107 @dfn{inferiors}, separate processes running a potentially different revision
8110 The available options are as follows:
8113 @item --type=@var{type}
8114 @itemx -t @var{type}
8115 Start a REPL of the given @var{TYPE}, which can be one of the following:
8119 This is default, and it spawns a standard full-featured Guile REPL.
8121 Spawn a REPL that uses the machine-readable protocol. This is the protocol
8122 that the @code{(guix inferior)} module speaks.
8125 @item --listen=@var{endpoint}
8126 By default, @command{guix repl} reads from standard input and writes to
8127 standard output. When this option is passed, it will instead listen for
8128 connections on @var{endpoint}. Here are examples of valid options:
8131 @item --listen=tcp:37146
8132 Accept connections on localhost on port 37146.
8134 @item --listen=unix:/tmp/socket
8135 Accept connections on the Unix-domain socket @file{/tmp/socket}.
8138 @item --load-path=@var{directory}
8139 @itemx -L @var{directory}
8140 Add @var{directory} to the front of the package module search path
8141 (@pxref{Package Modules}).
8143 This allows users to define their own packages and make them visible to
8144 the command-line tool.
8147 Inhibit loading of the @file{~/.guile} file. By default, that
8148 configuration file is loaded when spawning a @code{guile} REPL.
8151 @c *********************************************************************
8155 This section describes Guix command-line utilities. Some of them are
8156 primarily targeted at developers and users who write new package
8157 definitions, while others are more generally useful. They complement
8158 the Scheme programming interface of Guix in a convenient way.
8161 * Invoking guix build:: Building packages from the command line.
8162 * Invoking guix edit:: Editing package definitions.
8163 * Invoking guix download:: Downloading a file and printing its hash.
8164 * Invoking guix hash:: Computing the cryptographic hash of a file.
8165 * Invoking guix import:: Importing package definitions.
8166 * Invoking guix refresh:: Updating package definitions.
8167 * Invoking guix lint:: Finding errors in package definitions.
8168 * Invoking guix size:: Profiling disk usage.
8169 * Invoking guix graph:: Visualizing the graph of packages.
8170 * Invoking guix publish:: Sharing substitutes.
8171 * Invoking guix challenge:: Challenging substitute servers.
8172 * Invoking guix copy:: Copying to and from a remote store.
8173 * Invoking guix container:: Process isolation.
8174 * Invoking guix weather:: Assessing substitute availability.
8175 * Invoking guix processes:: Listing client processes.
8178 @node Invoking guix build
8179 @section Invoking @command{guix build}
8181 @cindex package building
8182 @cindex @command{guix build}
8183 The @command{guix build} command builds packages or derivations and
8184 their dependencies, and prints the resulting store paths. Note that it
8185 does not modify the user's profile---this is the job of the
8186 @command{guix package} command (@pxref{Invoking guix package}). Thus,
8187 it is mainly useful for distribution developers.
8189 The general syntax is:
8192 guix build @var{options} @var{package-or-derivation}@dots{}
8195 As an example, the following command builds the latest versions of Emacs
8196 and of Guile, displays their build logs, and finally displays the
8197 resulting directories:
8200 guix build emacs guile
8203 Similarly, the following command builds all the available packages:
8206 guix build --quiet --keep-going \
8207 `guix package -A | cut -f1,2 --output-delimiter=@@`
8210 @var{package-or-derivation} may be either the name of a package found in
8211 the software distribution such as @code{coreutils} or
8212 @code{coreutils@@8.20}, or a derivation such as
8213 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
8214 package with the corresponding name (and optionally version) is searched
8215 for among the GNU distribution modules (@pxref{Package Modules}).
8217 Alternatively, the @code{--expression} option may be used to specify a
8218 Scheme expression that evaluates to a package; this is useful when
8219 disambiguating among several same-named packages or package variants is
8222 There may be zero or more @var{options}. The available options are
8223 described in the subsections below.
8226 * Common Build Options:: Build options for most commands.
8227 * Package Transformation Options:: Creating variants of packages.
8228 * Additional Build Options:: Options specific to 'guix build'.
8229 * Debugging Build Failures:: Real life packaging experience.
8232 @node Common Build Options
8233 @subsection Common Build Options
8235 A number of options that control the build process are common to
8236 @command{guix build} and other commands that can spawn builds, such as
8237 @command{guix package} or @command{guix archive}. These are the
8242 @item --load-path=@var{directory}
8243 @itemx -L @var{directory}
8244 Add @var{directory} to the front of the package module search path
8245 (@pxref{Package Modules}).
8247 This allows users to define their own packages and make them visible to
8248 the command-line tools.
8252 Keep the build tree of failed builds. Thus, if a build fails, its build
8253 tree is kept under @file{/tmp}, in a directory whose name is shown at
8254 the end of the build log. This is useful when debugging build issues.
8255 @xref{Debugging Build Failures}, for tips and tricks on how to debug
8258 This option implies @option{--no-offload}, and it has no effect when
8259 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
8260 Store, the @code{GUIX_DAEMON_SOCKET} variable}).
8264 Keep going when some of the derivations fail to build; return only once
8265 all the builds have either completed or failed.
8267 The default behavior is to stop as soon as one of the specified
8268 derivations has failed.
8272 Do not build the derivations.
8274 @anchor{fallback-option}
8276 When substituting a pre-built binary fails, fall back to building
8277 packages locally (@pxref{Substitution Failure}).
8279 @item --substitute-urls=@var{urls}
8280 @anchor{client-substitute-urls}
8281 Consider @var{urls} the whitespace-separated list of substitute source
8282 URLs, overriding the default list of URLs of @command{guix-daemon}
8283 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
8285 This means that substitutes may be downloaded from @var{urls}, provided
8286 they are signed by a key authorized by the system administrator
8287 (@pxref{Substitutes}).
8289 When @var{urls} is the empty string, substitutes are effectively
8292 @item --no-substitutes
8293 Do not use substitutes for build products. That is, always build things
8294 locally instead of allowing downloads of pre-built binaries
8295 (@pxref{Substitutes}).
8298 Do not ``graft'' packages. In practice, this means that package updates
8299 available as grafts are not applied. @xref{Security Updates}, for more
8300 information on grafts.
8302 @item --rounds=@var{n}
8303 Build each derivation @var{n} times in a row, and raise an error if
8304 consecutive build results are not bit-for-bit identical.
8306 This is a useful way to detect non-deterministic builds processes.
8307 Non-deterministic build processes are a problem because they make it
8308 practically impossible for users to @emph{verify} whether third-party
8309 binaries are genuine. @xref{Invoking guix challenge}, for more.
8311 Note that, currently, the differing build results are not kept around,
8312 so you will have to manually investigate in case of an error---e.g., by
8313 stashing one of the build results with @code{guix archive --export}
8314 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8318 Do not use offload builds to other machines (@pxref{Daemon Offload
8319 Setup}). That is, always build things locally instead of offloading
8320 builds to remote machines.
8322 @item --max-silent-time=@var{seconds}
8323 When the build or substitution process remains silent for more than
8324 @var{seconds}, terminate it and report a build failure.
8326 By default, the daemon's setting is honored (@pxref{Invoking
8327 guix-daemon, @code{--max-silent-time}}).
8329 @item --timeout=@var{seconds}
8330 Likewise, when the build or substitution process lasts for more than
8331 @var{seconds}, terminate it and report a build failure.
8333 By default, the daemon's setting is honored (@pxref{Invoking
8334 guix-daemon, @code{--timeout}}).
8336 @c Note: This option is actually not part of %standard-build-options but
8337 @c most programs honor it.
8338 @cindex verbosity, of the command-line tools
8339 @cindex build logs, verbosity
8340 @item -v @var{level}
8341 @itemx --verbosity=@var{level}
8342 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8343 output is produced, 1 is for quiet output, and 2 shows all the build log
8344 output on standard error.
8346 @item --cores=@var{n}
8348 Allow the use of up to @var{n} CPU cores for the build. The special
8349 value @code{0} means to use as many CPU cores as available.
8351 @item --max-jobs=@var{n}
8353 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8354 guix-daemon, @code{--max-jobs}}, for details about this option and the
8355 equivalent @command{guix-daemon} option.
8357 @item --debug=@var{level}
8358 Produce debugging output coming from the build daemon. @var{level} must be an
8359 integer between 0 and 5; higher means more verbose output. Setting a level of
8360 4 or more may be helpful when debugging setup issues with the build daemon.
8364 Behind the scenes, @command{guix build} is essentially an interface to
8365 the @code{package-derivation} procedure of the @code{(guix packages)}
8366 module, and to the @code{build-derivations} procedure of the @code{(guix
8367 derivations)} module.
8369 In addition to options explicitly passed on the command line,
8370 @command{guix build} and other @command{guix} commands that support
8371 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
8373 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8374 Users can define this variable to a list of command line options that
8375 will automatically be used by @command{guix build} and other
8376 @command{guix} commands that can perform builds, as in the example
8380 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8383 These options are parsed independently, and the result is appended to
8384 the parsed command-line options.
8388 @node Package Transformation Options
8389 @subsection Package Transformation Options
8391 @cindex package variants
8392 Another set of command-line options supported by @command{guix build}
8393 and also @command{guix package} are @dfn{package transformation
8394 options}. These are options that make it possible to define @dfn{package
8395 variants}---for instance, packages built from different source code.
8396 This is a convenient way to create customized packages on the fly
8397 without having to type in the definitions of package variants
8398 (@pxref{Defining Packages}).
8402 @item --with-source=@var{source}
8403 @itemx --with-source=@var{package}=@var{source}
8404 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8405 Use @var{source} as the source of @var{package}, and @var{version} as
8407 @var{source} must be a file name or a URL, as for @command{guix
8408 download} (@pxref{Invoking guix download}).
8410 When @var{package} is omitted,
8411 it is taken to be the package name specified on the
8412 command line that matches the base of @var{source}---e.g.,
8413 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8414 package is @code{guile}.
8416 Likewise, when @var{version} is omitted, the version string is inferred from
8417 @var{source}; in the previous example, it is @code{2.0.10}.
8419 This option allows users to try out versions of packages other than the
8420 one provided by the distribution. The example below downloads
8421 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8422 the @code{ed} package:
8425 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8428 As a developer, @code{--with-source} makes it easy to test release
8432 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8435 @dots{} or to build from a checkout in a pristine environment:
8438 $ git clone git://git.sv.gnu.org/guix.git
8439 $ guix build guix --with-source=guix@@1.0=./guix
8442 @item --with-input=@var{package}=@var{replacement}
8443 Replace dependency on @var{package} by a dependency on
8444 @var{replacement}. @var{package} must be a package name, and
8445 @var{replacement} must be a package specification such as @code{guile}
8446 or @code{guile@@1.8}.
8448 For instance, the following command builds Guix, but replaces its
8449 dependency on the current stable version of Guile with a dependency on
8450 the legacy version of Guile, @code{guile@@2.0}:
8453 guix build --with-input=guile=guile@@2.0 guix
8456 This is a recursive, deep replacement. So in this example, both
8457 @code{guix} and its dependency @code{guile-json} (which also depends on
8458 @code{guile}) get rebuilt against @code{guile@@2.0}.
8460 This is implemented using the @code{package-input-rewriting} Scheme
8461 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8463 @item --with-graft=@var{package}=@var{replacement}
8464 This is similar to @code{--with-input} but with an important difference:
8465 instead of rebuilding the whole dependency chain, @var{replacement} is
8466 built and then @dfn{grafted} onto the binaries that were initially
8467 referring to @var{package}. @xref{Security Updates}, for more
8468 information on grafts.
8470 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8471 and all its dependencies, replacing references to the version of GnuTLS
8472 they currently refer to:
8475 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8478 This has the advantage of being much faster than rebuilding everything.
8479 But there is a caveat: it works if and only if @var{package} and
8480 @var{replacement} are strictly compatible---for example, if they provide
8481 a library, the application binary interface (ABI) of those libraries
8482 must be compatible. If @var{replacement} is somehow incompatible with
8483 @var{package}, then the resulting package may be unusable. Use with
8486 @item --with-git-url=@var{package}=@var{url}
8487 @cindex Git, using the latest commit
8488 @cindex latest commit, building
8489 Build @var{package} from the latest commit of the @code{master} branch of the
8490 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8493 For example, the following command builds the NumPy Python library against the
8494 latest commit of the master branch of Python itself:
8497 guix build python-numpy \
8498 --with-git-url=python=https://github.com/python/cpython
8501 This option can also be combined with @code{--with-branch} or
8502 @code{--with-commit} (see below).
8504 @cindex continuous integration
8505 Obviously, since it uses the latest commit of the given branch, the result of
8506 such a command varies over time. Nevertheless it is a convenient way to
8507 rebuild entire software stacks against the latest commit of one or more
8508 packages. This is particularly useful in the context of continuous
8511 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8512 consecutive accesses to the same repository. You may want to clean it up once
8513 in a while to save disk space.
8515 @item --with-branch=@var{package}=@var{branch}
8516 Build @var{package} from the latest commit of @var{branch}. If the
8517 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8518 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8519 repository URL is taken from that @code{source}. Otherwise you have to use
8520 @code{--with-git-url} to specify the URL of the Git repository.
8522 For instance, the following command builds @code{guile-sqlite3} from the
8523 latest commit of its @code{master} branch, and then builds @code{guix} (which
8524 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8525 specific @code{guile-sqlite3} build:
8528 guix build --with-branch=guile-sqlite3=master cuirass
8531 @item --with-commit=@var{package}=@var{commit}
8532 This is similar to @code{--with-branch}, except that it builds from
8533 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8534 Git commit SHA1 identifier or a tag.
8537 @node Additional Build Options
8538 @subsection Additional Build Options
8540 The command-line options presented below are specific to @command{guix
8547 Build quietly, without displaying the build log; this is equivalent to
8548 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8549 (or similar) and can always be retrieved using the @option{--log-file} option.
8551 @item --file=@var{file}
8552 @itemx -f @var{file}
8553 Build the package, derivation, or other file-like object that the code within
8554 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8556 As an example, @var{file} might contain a package definition like this
8557 (@pxref{Defining Packages}):
8560 @include package-hello.scm
8563 The @var{file} may also contain a JSON representation of one or more
8564 package definitions. Running @code{guix build -f} on @file{hello.json}
8565 with the following contents would result in building the packages
8566 @code{myhello} and @code{greeter}:
8569 @verbatiminclude package-hello.json
8572 @item --manifest=@var{manifest}
8573 @itemx -m @var{manifest}
8574 Build all packages listed in the given @var{manifest}
8575 (@pxref{profile-manifest, @option{--manifest}}).
8577 @item --expression=@var{expr}
8578 @itemx -e @var{expr}
8579 Build the package or derivation @var{expr} evaluates to.
8581 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8582 guile-1.8)}, which unambiguously designates this specific variant of
8583 version 1.8 of Guile.
8585 Alternatively, @var{expr} may be a G-expression, in which case it is used
8586 as a build program passed to @code{gexp->derivation}
8587 (@pxref{G-Expressions}).
8589 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8590 (@pxref{The Store Monad}). The procedure must return a derivation as a
8591 monadic value, which is then passed through @code{run-with-store}.
8595 Build the source derivations of the packages, rather than the packages
8598 For instance, @code{guix build -S gcc} returns something like
8599 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8602 The returned source tarball is the result of applying any patches and
8603 code snippets specified in the package @code{origin} (@pxref{Defining
8606 Note that @command{guix build -S} compiles the sources only of the
8607 specified packages. They do not include the sources of statically
8608 linked dependencies and by themselves are insufficient for reproducing
8612 Fetch and return the source of @var{package-or-derivation} and all their
8613 dependencies, recursively. This is a handy way to obtain a local copy
8614 of all the source code needed to build @var{packages}, allowing you to
8615 eventually build them even without network access. It is an extension
8616 of the @code{--source} option and can accept one of the following
8617 optional argument values:
8621 This value causes the @code{--sources} option to behave in the same way
8622 as the @code{--source} option.
8625 Build the source derivations of all packages, including any source that
8626 might be listed as @code{inputs}. This is the default value.
8629 $ guix build --sources tzdata
8630 The following derivations will be built:
8631 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8632 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8636 Build the source derivations of all packages, as well of all transitive
8637 inputs to the packages. This can be used e.g.@: to
8638 prefetch package source for later offline building.
8641 $ guix build --sources=transitive tzdata
8642 The following derivations will be built:
8643 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8644 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8645 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8646 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8647 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8648 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8654 @item --system=@var{system}
8655 @itemx -s @var{system}
8656 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8657 the system type of the build host. The @command{guix build} command allows
8658 you to repeat this option several times, in which case it builds for all the
8659 specified systems; other commands ignore extraneous @option{-s} options.
8662 The @code{--system} flag is for @emph{native} compilation and must not
8663 be confused with cross-compilation. See @code{--target} below for
8664 information on cross-compilation.
8667 An example use of this is on Linux-based systems, which can emulate
8668 different personalities. For instance, passing
8669 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8670 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8671 to build packages in a complete 32-bit environment.
8674 Building for an @code{armhf-linux} system is unconditionally enabled on
8675 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8676 allow for this functionality, notably the ThunderX.
8679 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8680 is enabled (@pxref{Virtualization Services,
8681 @code{qemu-binfmt-service-type}}), you can build for any system for
8682 which a QEMU @code{binfmt_misc} handler is installed.
8684 Builds for a system other than that of the machine you are using can
8685 also be offloaded to a remote machine of the right architecture.
8686 @xref{Daemon Offload Setup}, for more information on offloading.
8688 @item --target=@var{triplet}
8689 @cindex cross-compilation
8690 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8691 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8692 configuration triplets,, autoconf, Autoconf}).
8694 @anchor{build-check}
8696 @cindex determinism, checking
8697 @cindex reproducibility, checking
8698 Rebuild @var{package-or-derivation}, which are already available in the
8699 store, and raise an error if the build results are not bit-for-bit
8702 This mechanism allows you to check whether previously installed
8703 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8704 of a package is deterministic. @xref{Invoking guix challenge}, for more
8705 background information and tools.
8707 When used in conjunction with @option{--keep-failed}, the differing
8708 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8709 This makes it easy to look for differences between the two results.
8712 @cindex repairing store items
8713 @cindex corruption, recovering from
8714 Attempt to repair the specified store items, if they are corrupt, by
8715 re-downloading or rebuilding them.
8717 This operation is not atomic and thus restricted to @code{root}.
8721 Return the derivation paths, not the output paths, of the given
8724 @item --root=@var{file}
8725 @itemx -r @var{file}
8726 @cindex GC roots, adding
8727 @cindex garbage collector roots, adding
8728 Make @var{file} a symlink to the result, and register it as a garbage
8731 Consequently, the results of this @command{guix build} invocation are
8732 protected from garbage collection until @var{file} is removed. When
8733 that option is omitted, build results are eligible for garbage
8734 collection as soon as the build completes. @xref{Invoking guix gc}, for
8738 @cindex build logs, access
8739 Return the build log file names or URLs for the given
8740 @var{package-or-derivation}, or raise an error if build logs are
8743 This works regardless of how packages or derivations are specified. For
8744 instance, the following invocations are equivalent:
8747 guix build --log-file `guix build -d guile`
8748 guix build --log-file `guix build guile`
8749 guix build --log-file guile
8750 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8753 If a log is unavailable locally, and unless @code{--no-substitutes} is
8754 passed, the command looks for a corresponding log on one of the
8755 substitute servers (as specified with @code{--substitute-urls}.)
8757 So for instance, imagine you want to see the build log of GDB on MIPS,
8758 but you are actually on an @code{x86_64} machine:
8761 $ guix build --log-file gdb -s mips64el-linux
8762 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8765 You can freely access a huge library of build logs!
8768 @node Debugging Build Failures
8769 @subsection Debugging Build Failures
8771 @cindex build failures, debugging
8772 When defining a new package (@pxref{Defining Packages}), you will
8773 probably find yourself spending some time debugging and tweaking the
8774 build until it succeeds. To do that, you need to operate the build
8775 commands yourself in an environment as close as possible to the one the
8778 To that end, the first thing to do is to use the @option{--keep-failed}
8779 or @option{-K} option of @command{guix build}, which will keep the
8780 failed build tree in @file{/tmp} or whatever directory you specified as
8781 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8783 From there on, you can @command{cd} to the failed build tree and source
8784 the @file{environment-variables} file, which contains all the
8785 environment variable definitions that were in place when the build
8786 failed. So let's say you're debugging a build failure in package
8787 @code{foo}; a typical session would look like this:
8791 @dots{} @i{build fails}
8792 $ cd /tmp/guix-build-foo.drv-0
8793 $ source ./environment-variables
8797 Now, you can invoke commands as if you were the daemon (almost) and
8798 troubleshoot your build process.
8800 Sometimes it happens that, for example, a package's tests pass when you
8801 run them manually but they fail when the daemon runs them. This can
8802 happen because the daemon runs builds in containers where, unlike in our
8803 environment above, network access is missing, @file{/bin/sh} does not
8804 exist, etc. (@pxref{Build Environment Setup}).
8806 In such cases, you may need to run inspect the build process from within
8807 a container similar to the one the build daemon creates:
8812 $ cd /tmp/guix-build-foo.drv-0
8813 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8814 [env]# source ./environment-variables
8818 Here, @command{guix environment -C} creates a container and spawns a new
8819 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8820 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8821 the container, which would may find handy while debugging. The
8822 @option{--no-grafts} option makes sure we get the exact same
8823 environment, with ungrafted packages (@pxref{Security Updates}, for more
8826 To get closer to a container like that used by the build daemon, we can
8827 remove @file{/bin/sh}:
8833 (Don't worry, this is harmless: this is all happening in the throw-away
8834 container created by @command{guix environment}.)
8836 The @command{strace} command is probably not in the search path, but we
8840 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8843 In this way, not only you will have reproduced the environment variables
8844 the daemon uses, you will also be running the build process in a container
8845 similar to the one the daemon uses.
8848 @node Invoking guix edit
8849 @section Invoking @command{guix edit}
8851 @cindex @command{guix edit}
8852 @cindex package definition, editing
8853 So many packages, so many source files! The @command{guix edit} command
8854 facilitates the life of users and packagers by pointing their editor at
8855 the source file containing the definition of the specified packages.
8859 guix edit gcc@@4.9 vim
8863 launches the program specified in the @code{VISUAL} or in the
8864 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8867 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8868 have created your own packages on @code{GUIX_PACKAGE_PATH}
8869 (@pxref{Package Modules}), you will be able to edit the package
8870 recipes. In other cases, you will be able to examine the read-only recipes
8871 for packages currently in the store.
8873 Instead of @code{GUIX_PACKAGE_PATH}, the command-line option
8874 @code{--load-path=@var{directory}} (or in short @code{-L
8875 @var{directory}}) allows you to add @var{directory} to the front of the
8876 package module search path and so make your own packages visible.
8878 @node Invoking guix download
8879 @section Invoking @command{guix download}
8881 @cindex @command{guix download}
8882 @cindex downloading package sources
8883 When writing a package definition, developers typically need to download
8884 a source tarball, compute its SHA256 hash, and write that
8885 hash in the package definition (@pxref{Defining Packages}). The
8886 @command{guix download} tool helps with this task: it downloads a file
8887 from the given URI, adds it to the store, and prints both its file name
8888 in the store and its SHA256 hash.
8890 The fact that the downloaded file is added to the store saves bandwidth:
8891 when the developer eventually tries to build the newly defined package
8892 with @command{guix build}, the source tarball will not have to be
8893 downloaded again because it is already in the store. It is also a
8894 convenient way to temporarily stash files, which may be deleted
8895 eventually (@pxref{Invoking guix gc}).
8897 The @command{guix download} command supports the same URIs as used in
8898 package definitions. In particular, it supports @code{mirror://} URIs.
8899 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8900 Guile bindings for GnuTLS are available in the user's environment; when
8901 they are not available, an error is raised. @xref{Guile Preparations,
8902 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8903 GnuTLS-Guile}, for more information.
8905 @command{guix download} verifies HTTPS server certificates by loading
8906 the certificates of X.509 authorities from the directory pointed to by
8907 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8908 Certificates}), unless @option{--no-check-certificate} is used.
8910 The following options are available:
8913 @item --format=@var{fmt}
8915 Write the hash in the format specified by @var{fmt}. For more
8916 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8918 @item --no-check-certificate
8919 Do not validate the X.509 certificates of HTTPS servers.
8921 When using this option, you have @emph{absolutely no guarantee} that you
8922 are communicating with the authentic server responsible for the given
8923 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8925 @item --output=@var{file}
8926 @itemx -o @var{file}
8927 Save the downloaded file to @var{file} instead of adding it to the
8931 @node Invoking guix hash
8932 @section Invoking @command{guix hash}
8934 @cindex @command{guix hash}
8935 The @command{guix hash} command computes the SHA256 hash of a file.
8936 It is primarily a convenience tool for anyone contributing to the
8937 distribution: it computes the cryptographic hash of a file, which can be
8938 used in the definition of a package (@pxref{Defining Packages}).
8940 The general syntax is:
8943 guix hash @var{option} @var{file}
8946 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8947 hash of data read from standard input. @command{guix hash} has the
8952 @item --format=@var{fmt}
8954 Write the hash in the format specified by @var{fmt}.
8956 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8957 (@code{hex} and @code{hexadecimal} can be used as well).
8959 If the @option{--format} option is not specified, @command{guix hash}
8960 will output the hash in @code{nix-base32}. This representation is used
8961 in the definitions of packages.
8965 Compute the hash on @var{file} recursively.
8967 In this case, the hash is computed on an archive containing @var{file},
8968 including its children if it is a directory. Some of the metadata of
8969 @var{file} is part of the archive; for instance, when @var{file} is a
8970 regular file, the hash is different depending on whether @var{file} is
8971 executable or not. Metadata such as time stamps has no impact on the
8972 hash (@pxref{Invoking guix archive}).
8973 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8978 When combined with @option{--recursive}, exclude version control system
8979 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8982 As an example, here is how you would compute the hash of a Git checkout,
8983 which is useful when using the @code{git-fetch} method (@pxref{origin
8987 $ git clone http://example.org/foo.git
8993 @node Invoking guix import
8994 @section Invoking @command{guix import}
8996 @cindex importing packages
8997 @cindex package import
8998 @cindex package conversion
8999 @cindex Invoking @command{guix import}
9000 The @command{guix import} command is useful for people who would like to
9001 add a package to the distribution with as little work as
9002 possible---a legitimate demand. The command knows of a few
9003 repositories from which it can ``import'' package metadata. The result
9004 is a package definition, or a template thereof, in the format we know
9005 (@pxref{Defining Packages}).
9007 The general syntax is:
9010 guix import @var{importer} @var{options}@dots{}
9013 @var{importer} specifies the source from which to import package
9014 metadata, and @var{options} specifies a package identifier and other
9015 options specific to @var{importer}.
9017 Some of the importers rely on the ability to run the @command{gpgv} command.
9018 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
9021 Currently, the available ``importers'' are:
9025 Import metadata for the given GNU package. This provides a template
9026 for the latest version of that GNU package, including the hash of its
9027 source tarball, and its canonical synopsis and description.
9029 Additional information such as the package dependencies and its
9030 license needs to be figured out manually.
9032 For example, the following command returns a package definition for
9036 guix import gnu hello
9039 Specific command-line options are:
9042 @item --key-download=@var{policy}
9043 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
9044 keys when verifying the package signature. @xref{Invoking guix
9045 refresh, @code{--key-download}}.
9050 Import metadata from the @uref{https://pypi.python.org/, Python Package
9051 Index}. Information is taken from the JSON-formatted description
9052 available at @code{pypi.python.org} and usually includes all the relevant
9053 information, including package dependencies. For maximum efficiency, it
9054 is recommended to install the @command{unzip} utility, so that the
9055 importer can unzip Python wheels and gather data from them.
9057 The command below imports metadata for the @code{itsdangerous} Python
9061 guix import pypi itsdangerous
9067 Traverse the dependency graph of the given upstream package recursively
9068 and generate package expressions for all those packages that are not yet
9074 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
9075 is taken from the JSON-formatted description available at
9076 @code{rubygems.org} and includes most relevant information, including
9077 runtime dependencies. There are some caveats, however. The metadata
9078 doesn't distinguish between synopses and descriptions, so the same string
9079 is used for both fields. Additionally, the details of non-Ruby
9080 dependencies required to build native extensions is unavailable and left
9081 as an exercise to the packager.
9083 The command below imports metadata for the @code{rails} Ruby package:
9086 guix import gem rails
9092 Traverse the dependency graph of the given upstream package recursively
9093 and generate package expressions for all those packages that are not yet
9099 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
9100 Information is taken from the JSON-formatted metadata provided through
9101 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
9102 relevant information, such as module dependencies. License information
9103 should be checked closely. If Perl is available in the store, then the
9104 @code{corelist} utility will be used to filter core modules out of the
9105 list of dependencies.
9107 The command command below imports metadata for the @code{Acme::Boolean}
9111 guix import cpan Acme::Boolean
9116 @cindex Bioconductor
9117 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
9118 central repository for the @uref{https://r-project.org, GNU@tie{}R
9119 statistical and graphical environment}.
9121 Information is extracted from the @code{DESCRIPTION} file of the package.
9123 The command command below imports metadata for the @code{Cairo}
9127 guix import cran Cairo
9130 When @code{--recursive} is added, the importer will traverse the
9131 dependency graph of the given upstream package recursively and generate
9132 package expressions for all those packages that are not yet in Guix.
9134 When @code{--archive=bioconductor} is added, metadata is imported from
9135 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
9136 packages for for the analysis and comprehension of high-throughput
9137 genomic data in bioinformatics.
9139 Information is extracted from the @code{DESCRIPTION} file contained in the
9142 The command below imports metadata for the @code{GenomicRanges}
9146 guix import cran --archive=bioconductor GenomicRanges
9149 Finally, you can also import R packages that have not yet been published on
9150 CRAN or Bioconductor as long as they are in a git repository. Use
9151 @code{--archive=git} followed by the URL of the git repository:
9154 guix import cran --archive=git https://github.com/immunogenomics/harmony
9160 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
9161 comprehensive TeX archive network for TeX packages that are part of the
9162 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
9164 Information about the package is obtained through the XML API provided
9165 by CTAN, while the source code is downloaded from the SVN repository of
9166 the Tex Live project. This is done because the CTAN does not keep
9169 The command command below imports metadata for the @code{fontspec}
9173 guix import texlive fontspec
9176 When @code{--archive=DIRECTORY} is added, the source code is downloaded
9177 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
9178 tree in the TeX Live SVN repository, but from the specified sibling
9179 directory under the same root.
9181 The command below imports metadata for the @code{ifxetex} package from
9182 CTAN while fetching the sources from the directory
9183 @file{texmf/source/generic}:
9186 guix import texlive --archive=generic ifxetex
9190 @cindex JSON, import
9191 Import package metadata from a local JSON file. Consider the following
9192 example package definition in JSON format:
9198 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
9199 "build-system": "gnu",
9200 "home-page": "https://www.gnu.org/software/hello/",
9201 "synopsis": "Hello, GNU world: An example GNU package",
9202 "description": "GNU Hello prints a greeting.",
9203 "license": "GPL-3.0+",
9204 "native-inputs": ["gettext"]
9208 The field names are the same as for the @code{<package>} record
9209 (@xref{Defining Packages}). References to other packages are provided
9210 as JSON lists of quoted package specification strings such as
9211 @code{guile} or @code{guile@@2.0}.
9213 The importer also supports a more explicit source definition using the
9214 common fields for @code{<origin>} records:
9220 "method": "url-fetch",
9221 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
9223 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
9230 The command below reads metadata from the JSON file @code{hello.json}
9231 and outputs a package expression:
9234 guix import json hello.json
9238 Import metadata from a local copy of the source of the
9239 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
9240 relies on the @command{nix-instantiate} command of
9241 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
9242 typically written in a mixture of Nix-language and Bash code. This
9243 command only imports the high-level package structure that is written in
9244 the Nix language. It normally includes all the basic fields of a
9247 When importing a GNU package, the synopsis and descriptions are replaced
9248 by their canonical upstream variant.
9250 Usually, you will first need to do:
9253 export NIX_REMOTE=daemon
9257 so that @command{nix-instantiate} does not try to open the Nix database.
9259 As an example, the command below imports the package definition of
9260 LibreOffice (more precisely, it imports the definition of the package
9261 bound to the @code{libreoffice} top-level attribute):
9264 guix import nix ~/path/to/nixpkgs libreoffice
9269 Import metadata from the Haskell community's central package archive
9270 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
9271 Cabal files and includes all the relevant information, including package
9274 Specific command-line options are:
9279 Read a Cabal file from standard input.
9280 @item --no-test-dependencies
9282 Do not include dependencies required only by the test suites.
9283 @item --cabal-environment=@var{alist}
9284 @itemx -e @var{alist}
9285 @var{alist} is a Scheme alist defining the environment in which the
9286 Cabal conditionals are evaluated. The accepted keys are: @code{os},
9287 @code{arch}, @code{impl} and a string representing the name of a flag.
9288 The value associated with a flag has to be either the symbol
9289 @code{true} or @code{false}. The value associated with other keys
9290 has to conform to the Cabal file format definition. The default value
9291 associated with the keys @code{os}, @code{arch} and @code{impl} is
9292 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
9295 Traverse the dependency graph of the given upstream package recursively
9296 and generate package expressions for all those packages that are not yet
9300 The command below imports metadata for the latest version of the
9301 @code{HTTP} Haskell package without including test dependencies and
9302 specifying the value of the flag @samp{network-uri} as @code{false}:
9305 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
9308 A specific package version may optionally be specified by following the
9309 package name by an at-sign and a version number as in the following example:
9312 guix import hackage mtl@@2.1.3.1
9317 The @code{stackage} importer is a wrapper around the @code{hackage} one.
9318 It takes a package name, looks up the package version included in a
9319 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
9320 release and uses the @code{hackage} importer to retrieve its metadata.
9321 Note that it is up to you to select an LTS release compatible with the
9322 GHC compiler used by Guix.
9324 Specific command-line options are:
9327 @item --no-test-dependencies
9329 Do not include dependencies required only by the test suites.
9330 @item --lts-version=@var{version}
9331 @itemx -l @var{version}
9332 @var{version} is the desired LTS release version. If omitted the latest
9336 Traverse the dependency graph of the given upstream package recursively
9337 and generate package expressions for all those packages that are not yet
9341 The command below imports metadata for the @code{HTTP} Haskell package
9342 included in the LTS Stackage release version 7.18:
9345 guix import stackage --lts-version=7.18 HTTP
9350 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9351 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9353 Specific command-line options are:
9356 @item --archive=@var{repo}
9357 @itemx -a @var{repo}
9358 @var{repo} identifies the archive repository from which to retrieve the
9359 information. Currently the supported repositories and their identifiers
9363 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9364 identifier. This is the default.
9366 Packages from @code{elpa.gnu.org} are signed with one of the keys
9367 contained in the GnuPG keyring at
9368 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9369 @code{emacs} package (@pxref{Package Installation, ELPA package
9370 signatures,, emacs, The GNU Emacs Manual}).
9373 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9374 @code{melpa-stable} identifier.
9377 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9383 Traverse the dependency graph of the given upstream package recursively
9384 and generate package expressions for all those packages that are not yet
9390 Import metadata from the crates.io Rust package repository
9391 @uref{https://crates.io, crates.io}, as in this example:
9394 guix import crate blake2-rfc
9397 The crate importer also allows you to specify a version string:
9400 guix import crate constant-time-eq@@0.1.0
9403 Additional options include:
9408 Traverse the dependency graph of the given upstream package recursively
9409 and generate package expressions for all those packages that are not yet
9416 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9417 repository used by the OCaml community.
9420 The structure of the @command{guix import} code is modular. It would be
9421 useful to have more importers for other package formats, and your help
9422 is welcome here (@pxref{Contributing}).
9424 @node Invoking guix refresh
9425 @section Invoking @command{guix refresh}
9427 @cindex @command {guix refresh}
9428 The primary audience of the @command{guix refresh} command is developers
9429 of the GNU software distribution. By default, it reports any packages
9430 provided by the distribution that are outdated compared to the latest
9431 upstream version, like this:
9435 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9436 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9439 Alternately, one can specify packages to consider, in which case a
9440 warning is emitted for packages that lack an updater:
9443 $ guix refresh coreutils guile guile-ssh
9444 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9445 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9448 @command{guix refresh} browses the upstream repository of each package and determines
9449 the highest version number of the releases therein. The command
9450 knows how to update specific types of packages: GNU packages, ELPA
9451 packages, etc.---see the documentation for @option{--type} below. There
9452 are many packages, though, for which it lacks a method to determine
9453 whether a new upstream release is available. However, the mechanism is
9454 extensible, so feel free to get in touch with us to add a new method!
9459 Consider the packages specified, and all the packages upon which they depend.
9462 $ guix refresh --recursive coreutils
9463 gnu/packages/acl.scm:35:2: warning: no updater for acl
9464 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9465 gnu/packages/xml.scm:68:2: warning: no updater for expat
9466 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9472 Sometimes the upstream name differs from the package name used in Guix,
9473 and @command{guix refresh} needs a little help. Most updaters honor the
9474 @code{upstream-name} property in package definitions, which can be used
9478 (define-public network-manager
9480 (name "network-manager")
9482 (properties '((upstream-name . "NetworkManager")))))
9485 When passed @code{--update}, it modifies distribution source files to
9486 update the version numbers and source tarball hashes of those package
9487 recipes (@pxref{Defining Packages}). This is achieved by downloading
9488 each package's latest source tarball and its associated OpenPGP
9489 signature, authenticating the downloaded tarball against its signature
9490 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
9491 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
9494 key used to sign the tarball is missing from the user's keyring, an
9495 attempt is made to automatically retrieve it from a public key server;
9496 when this is successful, the key is added to the user's keyring; otherwise,
9497 @command{guix refresh} reports an error.
9499 The following options are supported:
9503 @item --expression=@var{expr}
9504 @itemx -e @var{expr}
9505 Consider the package @var{expr} evaluates to.
9507 This is useful to precisely refer to a package, as in this example:
9510 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9513 This command lists the dependents of the ``final'' libc (essentially all
9518 Update distribution source files (package recipes) in place. This is
9519 usually run from a checkout of the Guix source tree (@pxref{Running
9520 Guix Before It Is Installed}):
9523 $ ./pre-inst-env guix refresh -s non-core -u
9526 @xref{Defining Packages}, for more information on package definitions.
9528 @item --select=[@var{subset}]
9529 @itemx -s @var{subset}
9530 Select all the packages in @var{subset}, one of @code{core} or
9533 The @code{core} subset refers to all the packages at the core of the
9534 distribution---i.e., packages that are used to build ``everything
9535 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9536 changing one of these packages in the distribution entails a rebuild of
9537 all the others. Thus, such updates are an inconvenience to users in
9538 terms of build time or bandwidth used to achieve the upgrade.
9540 The @code{non-core} subset refers to the remaining packages. It is
9541 typically useful in cases where an update of the core packages would be
9544 @item --manifest=@var{file}
9545 @itemx -m @var{file}
9546 Select all the packages from the manifest in @var{file}. This is useful to
9547 check if any packages of the user manifest can be updated.
9549 @item --type=@var{updater}
9550 @itemx -t @var{updater}
9551 Select only packages handled by @var{updater} (may be a comma-separated
9552 list of updaters). Currently, @var{updater} may be one of:
9556 the updater for GNU packages;
9558 the updater for GNOME packages;
9560 the updater for KDE packages;
9562 the updater for X.org packages;
9564 the updater for packages hosted on kernel.org;
9566 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9568 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9570 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9572 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9574 the updater for @uref{https://pypi.python.org, PyPI} packages.
9576 the updater for @uref{https://rubygems.org, RubyGems} packages.
9578 the updater for @uref{https://github.com, GitHub} packages.
9580 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9582 the updater for @uref{https://www.stackage.org, Stackage} packages.
9584 the updater for @uref{https://crates.io, Crates} packages.
9586 the updater for @uref{https://launchpad.net, Launchpad} packages.
9589 For instance, the following command only checks for updates of Emacs
9590 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9593 $ guix refresh --type=elpa,cran
9594 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9595 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9600 In addition, @command{guix refresh} can be passed one or more package
9601 names, as in this example:
9604 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9608 The command above specifically updates the @code{emacs} and
9609 @code{idutils} packages. The @code{--select} option would have no
9610 effect in this case.
9612 When considering whether to upgrade a package, it is sometimes
9613 convenient to know which packages would be affected by the upgrade and
9614 should be checked for compatibility. For this the following option may
9615 be used when passing @command{guix refresh} one or more package names:
9619 @item --list-updaters
9621 List available updaters and exit (see @option{--type} above.)
9623 For each updater, display the fraction of packages it covers; at the
9624 end, display the fraction of packages covered by all these updaters.
9626 @item --list-dependent
9628 List top-level dependent packages that would need to be rebuilt as a
9629 result of upgrading one or more packages.
9631 @xref{Invoking guix graph, the @code{reverse-package} type of
9632 @command{guix graph}}, for information on how to visualize the list of
9633 dependents of a package.
9637 Be aware that the @code{--list-dependent} option only
9638 @emph{approximates} the rebuilds that would be required as a result of
9639 an upgrade. More rebuilds might be required under some circumstances.
9642 $ guix refresh --list-dependent flex
9643 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9644 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9647 The command above lists a set of packages that could be built to check
9648 for compatibility with an upgraded @code{flex} package.
9652 @item --list-transitive
9653 List all the packages which one or more packages depend upon.
9656 $ guix refresh --list-transitive flex
9657 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9658 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{}
9663 The command above lists a set of packages which, when changed, would cause
9664 @code{flex} to be rebuilt.
9666 The following options can be used to customize GnuPG operation:
9670 @item --gpg=@var{command}
9671 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9672 for in @code{$PATH}.
9674 @item --keyring=@var{file}
9675 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9676 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9677 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9678 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9679 information on a tool to manipulate keybox files).
9681 When this option is omitted, @command{guix refresh} uses
9682 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9683 signing keys. OpenPGP signatures are checked against keys from this keyring;
9684 missing keys are downloaded to this keyring as well (see
9685 @option{--key-download} below.)
9687 You can export keys from your default GPG keyring into a keybox file using
9688 commands like this one:
9691 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9694 Likewise, you can fetch keys to a specific keybox file like this:
9697 gpg --no-default-keyring --keyring mykeyring.kbx \
9698 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9701 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9702 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9704 @item --key-download=@var{policy}
9705 Handle missing OpenPGP keys according to @var{policy}, which may be one
9710 Always download missing OpenPGP keys from the key server, and add them
9711 to the user's GnuPG keyring.
9714 Never try to download missing OpenPGP keys. Instead just bail out.
9717 When a package signed with an unknown OpenPGP key is encountered, ask
9718 the user whether to download it or not. This is the default behavior.
9721 @item --key-server=@var{host}
9722 Use @var{host} as the OpenPGP key server when importing a public key.
9724 @item --load-path=@var{directory}
9725 Add @var{directory} to the front of the package module search path
9726 (@pxref{Package Modules}).
9728 This allows users to define their own packages and make them visible to
9729 the command-line tools.
9733 The @code{github} updater uses the
9734 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9735 releases. When used repeatedly e.g.@: when refreshing all packages,
9736 GitHub will eventually refuse to answer any further API requests. By
9737 default 60 API requests per hour are allowed, and a full refresh on all
9738 GitHub packages in Guix requires more than this. Authentication with
9739 GitHub through the use of an API token alleviates these limits. To use
9740 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9741 token procured from @uref{https://github.com/settings/tokens} or
9745 @node Invoking guix lint
9746 @section Invoking @command{guix lint}
9748 @cindex @command{guix lint}
9749 @cindex package, checking for errors
9750 The @command{guix lint} command is meant to help package developers avoid
9751 common errors and use a consistent style. It runs a number of checks on
9752 a given set of packages in order to find common mistakes in their
9753 definitions. Available @dfn{checkers} include (see
9754 @code{--list-checkers} for a complete list):
9759 Validate certain typographical and stylistic rules about package
9760 descriptions and synopses.
9762 @item inputs-should-be-native
9763 Identify inputs that should most likely be native inputs.
9769 @itemx source-file-name
9770 Probe @code{home-page} and @code{source} URLs and report those that are
9771 invalid. Suggest a @code{mirror://} URL when applicable. If the
9772 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9773 URL. Check that the source file name is meaningful, e.g.@: is not just a
9774 version number or ``git-checkout'', without a declared @code{file-name}
9775 (@pxref{origin Reference}).
9777 @item source-unstable-tarball
9778 Parse the @code{source} URL to determine if a tarball from GitHub is
9779 autogenerated or if it is a release tarball. Unfortunately GitHub's
9780 autogenerated tarballs are sometimes regenerated.
9783 @cindex Software Heritage, source code archive
9784 @cindex archival of source code, Software Heritage
9785 Checks whether the package's source code is archived at
9786 @uref{https://www.softwareheritage.org, Software Heritage}.
9788 When the source code that is not archived comes from a version-control system
9789 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
9790 ``save'' request so that it eventually archives it. This ensures that the
9791 source will remain available in the long term, and that Guix can fall back to
9792 Software Heritage should the source code disappear from its original host.
9793 The status of recent ``save'' requests can be
9794 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
9796 When source code is a tarball obtained with @code{url-fetch}, simply print a
9797 message when it is not archived. As of this writing, Software Heritage does
9798 not allow requests to save arbitrary tarballs; we are working on ways to
9799 ensure that non-VCS source code is also archived.
9802 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
9803 request rate per IP address}. When the limit is reached, @command{guix lint}
9804 prints a message and the @code{archival} checker stops doing anything until
9805 that limit has been reset.
9808 @cindex security vulnerabilities
9809 @cindex CVE, Common Vulnerabilities and Exposures
9810 Report known vulnerabilities found in the Common Vulnerabilities and
9811 Exposures (CVE) databases of the current and past year
9812 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
9815 To view information about a particular vulnerability, visit pages such as:
9819 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9821 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9825 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9826 @code{CVE-2015-7554}.
9828 Package developers can specify in package recipes the
9829 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
9830 name and version of the package when they differ from the name or version
9831 that Guix uses, as in this example:
9837 ;; CPE calls this package "grub2".
9838 (properties '((cpe-name . "grub2")
9839 (cpe-version . "2.3"))))
9842 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9843 Some entries in the CVE database do not specify which version of a
9844 package they apply to, and would thus ``stick around'' forever. Package
9845 developers who found CVE alerts and verified they can be ignored can
9846 declare them as in this example:
9852 ;; These CVEs no longer apply and can be safely ignored.
9853 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9856 "CVE-2011-5244")))))
9860 Warn about obvious source code formatting issues: trailing white space,
9861 use of tabulations, etc.
9864 The general syntax is:
9867 guix lint @var{options} @var{package}@dots{}
9870 If no package is given on the command line, then all packages are checked.
9871 The @var{options} may be zero or more of the following:
9874 @item --list-checkers
9876 List and describe all the available checkers that will be run on packages
9881 Only enable the checkers specified in a comma-separated list using the
9882 names returned by @code{--list-checkers}.
9884 @item --load-path=@var{directory}
9885 @itemx -L @var{directory}
9886 Add @var{directory} to the front of the package module search path
9887 (@pxref{Package Modules}).
9889 This allows users to define their own packages and make them visible to
9890 the command-line tools.
9894 @node Invoking guix size
9895 @section Invoking @command{guix size}
9898 @cindex package size
9900 @cindex @command{guix size}
9901 The @command{guix size} command helps package developers profile the
9902 disk usage of packages. It is easy to overlook the impact of an
9903 additional dependency added to a package, or the impact of using a
9904 single output for a package that could easily be split (@pxref{Packages
9905 with Multiple Outputs}). Such are the typical issues that
9906 @command{guix size} can highlight.
9908 The command can be passed one or more package specifications
9909 such as @code{gcc@@4.8}
9910 or @code{guile:debug}, or a file name in the store. Consider this
9914 $ guix size coreutils
9915 store item total self
9916 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9917 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9918 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9919 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9920 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9921 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9922 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9923 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9928 The store items listed here constitute the @dfn{transitive closure} of
9929 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9930 would be returned by:
9933 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9936 Here the output shows three columns next to store items. The first column,
9937 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9938 the store item---that is, its own size plus the size of all its
9939 dependencies. The next column, labeled ``self'', shows the size of the
9940 item itself. The last column shows the ratio of the size of the item
9941 itself to the space occupied by all the items listed here.
9943 In this example, we see that the closure of Coreutils weighs in at
9944 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9945 libraries. (That libc and GCC's libraries represent a large fraction of
9946 the closure is not a problem @i{per se} because they are always available
9947 on the system anyway.)
9949 When the package(s) passed to @command{guix size} are available in the
9950 store@footnote{More precisely, @command{guix size} looks for the
9951 @emph{ungrafted} variant of the given package(s), as returned by
9952 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9953 for information on grafts.}, @command{guix size} queries the daemon to determine its
9954 dependencies, and measures its size in the store, similar to @command{du
9955 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9958 When the given packages are @emph{not} in the store, @command{guix size}
9959 reports information based on the available substitutes
9960 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9961 store items that are not even on disk, only available remotely.
9963 You can also specify several package names:
9966 $ guix size coreutils grep sed bash
9967 store item total self
9968 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9969 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9970 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9971 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9977 In this example we see that the combination of the four packages takes
9978 102.3@tie{}MiB in total, which is much less than the sum of each closure
9979 since they have a lot of dependencies in common.
9981 The available options are:
9985 @item --substitute-urls=@var{urls}
9986 Use substitute information from @var{urls}.
9987 @xref{client-substitute-urls, the same option for @code{guix build}}.
9989 @item --sort=@var{key}
9990 Sort lines according to @var{key}, one of the following options:
9994 the size of each item (the default);
9996 the total size of the item's closure.
9999 @item --map-file=@var{file}
10000 Write a graphical map of disk usage in PNG format to @var{file}.
10002 For the example above, the map looks like this:
10004 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
10005 produced by @command{guix size}}
10007 This option requires that
10008 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
10009 installed and visible in Guile's module search path. When that is not
10010 the case, @command{guix size} fails as it tries to load it.
10012 @item --system=@var{system}
10013 @itemx -s @var{system}
10014 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
10016 @item --load-path=@var{directory}
10017 @itemx -L @var{directory}
10018 Add @var{directory} to the front of the package module search path
10019 (@pxref{Package Modules}).
10021 This allows users to define their own packages and make them visible to
10022 the command-line tools.
10025 @node Invoking guix graph
10026 @section Invoking @command{guix graph}
10029 @cindex @command{guix graph}
10030 @cindex package dependencies
10031 Packages and their dependencies form a @dfn{graph}, specifically a
10032 directed acyclic graph (DAG). It can quickly become difficult to have a
10033 mental model of the package DAG, so the @command{guix graph} command
10034 provides a visual representation of the DAG. By default,
10035 @command{guix graph} emits a DAG representation in the input format of
10036 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
10037 directly to the @command{dot} command of Graphviz. It can also emit an
10038 HTML page with embedded JavaScript code to display a ``chord diagram''
10039 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
10040 emit Cypher queries to construct a graph in a graph database supporting
10041 the @uref{https://www.opencypher.org/, openCypher} query language.
10042 The general syntax is:
10045 guix graph @var{options} @var{package}@dots{}
10048 For example, the following command generates a PDF file representing the
10049 package DAG for the GNU@tie{}Core Utilities, showing its build-time
10053 guix graph coreutils | dot -Tpdf > dag.pdf
10056 The output looks like this:
10058 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
10060 Nice little graph, no?
10062 But there is more than one graph! The one above is concise: it is the
10063 graph of package objects, omitting implicit inputs such as GCC, libc,
10064 grep, etc. It is often useful to have such a concise graph, but
10065 sometimes one may want to see more details. @command{guix graph} supports
10066 several types of graphs, allowing you to choose the level of detail:
10070 This is the default type used in the example above. It shows the DAG of
10071 package objects, excluding implicit dependencies. It is concise, but
10072 filters out many details.
10074 @item reverse-package
10075 This shows the @emph{reverse} DAG of packages. For example:
10078 guix graph --type=reverse-package ocaml
10081 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
10082 you are also interested in cases where OCaml is an implicit dependency, see
10083 @code{reverse-bag} below.)
10085 Note that for core packages this can yield huge graphs. If all you want
10086 is to know the number of packages that depend on a given package, use
10087 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
10088 @option{--list-dependent}}).
10091 This is the package DAG, @emph{including} implicit inputs.
10093 For instance, the following command:
10096 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
10099 ...@: yields this bigger graph:
10101 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
10103 At the bottom of the graph, we see all the implicit inputs of
10104 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
10106 Now, note that the dependencies of these implicit inputs---that is, the
10107 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
10108 here, for conciseness.
10111 Similar to @code{bag-emerged}, but this time including all the bootstrap
10114 @item bag-with-origins
10115 Similar to @code{bag}, but also showing origins and their dependencies.
10118 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
10119 it also takes implicit dependencies into account. For example:
10122 guix graph -t reverse-bag dune
10126 ...@: yields the graph of all packages that depend on Dune, directly or
10127 indirectly. Since Dune is an @emph{implicit} dependency of many packages
10128 @i{via} @code{dune-build-system}, this shows a large number of packages,
10129 whereas @code{reverse-package} would show very few if any.
10132 This is the most detailed representation: It shows the DAG of
10133 derivations (@pxref{Derivations}) and plain store items. Compared to
10134 the above representation, many additional nodes are visible, including
10135 build scripts, patches, Guile modules, etc.
10137 For this type of graph, it is also possible to pass a @file{.drv} file
10138 name instead of a package name, as in:
10141 guix graph -t derivation `guix system build -d my-config.scm`
10145 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
10146 For example, the following command shows the graph for the package
10147 module that defines the @code{guile} package:
10150 guix graph -t module guile | dot -Tpdf > module-graph.pdf
10154 All the types above correspond to @emph{build-time dependencies}. The
10155 following graph type represents the @emph{run-time dependencies}:
10159 This is the graph of @dfn{references} of a package output, as returned
10160 by @command{guix gc --references} (@pxref{Invoking guix gc}).
10162 If the given package output is not available in the store, @command{guix
10163 graph} attempts to obtain dependency information from substitutes.
10165 Here you can also pass a store file name instead of a package name. For
10166 example, the command below produces the reference graph of your profile
10167 (which can be big!):
10170 guix graph -t references `readlink -f ~/.guix-profile`
10174 This is the graph of the @dfn{referrers} of a store item, as returned by
10175 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
10177 This relies exclusively on local information from your store. For
10178 instance, let us suppose that the current Inkscape is available in 10
10179 profiles on your machine; @command{guix graph -t referrers inkscape}
10180 will show a graph rooted at Inkscape and with those 10 profiles linked
10183 It can help determine what is preventing a store item from being garbage
10188 The available options are the following:
10191 @item --type=@var{type}
10192 @itemx -t @var{type}
10193 Produce a graph output of @var{type}, where @var{type} must be one of
10194 the values listed above.
10197 List the supported graph types.
10199 @item --backend=@var{backend}
10200 @itemx -b @var{backend}
10201 Produce a graph using the selected @var{backend}.
10203 @item --list-backends
10204 List the supported graph backends.
10206 Currently, the available backends are Graphviz and d3.js.
10208 @item --expression=@var{expr}
10209 @itemx -e @var{expr}
10210 Consider the package @var{expr} evaluates to.
10212 This is useful to precisely refer to a package, as in this example:
10215 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
10218 @item --system=@var{system}
10219 @itemx -s @var{system}
10220 Display the graph for @var{system}---e.g., @code{i686-linux}.
10222 The package dependency graph is largely architecture-independent, but there
10223 are some architecture-dependent bits that this option allows you to visualize.
10225 @item --load-path=@var{directory}
10226 @itemx -L @var{directory}
10227 Add @var{directory} to the front of the package module search path
10228 (@pxref{Package Modules}).
10230 This allows users to define their own packages and make them visible to
10231 the command-line tools.
10234 On top of that, @command{guix graph} supports all the usual package
10235 transformation options (@pxref{Package Transformation Options}). This
10236 makes it easy to view the effect of a graph-rewriting transformation
10237 such as @option{--with-input}. For example, the command below outputs
10238 the graph of @code{git} once @code{openssl} has been replaced by
10239 @code{libressl} everywhere in the graph:
10242 guix graph git --with-input=openssl=libressl
10245 So many possibilities, so much fun!
10247 @node Invoking guix publish
10248 @section Invoking @command{guix publish}
10250 @cindex @command{guix publish}
10251 The purpose of @command{guix publish} is to enable users to easily share
10252 their store with others, who can then use it as a substitute server
10253 (@pxref{Substitutes}).
10255 When @command{guix publish} runs, it spawns an HTTP server which allows
10256 anyone with network access to obtain substitutes from it. This means
10257 that any machine running Guix can also act as if it were a build farm,
10258 since the HTTP interface is compatible with Cuirass, the software behind
10259 the @code{@value{SUBSTITUTE-SERVER}} build farm.
10261 For security, each substitute is signed, allowing recipients to check
10262 their authenticity and integrity (@pxref{Substitutes}). Because
10263 @command{guix publish} uses the signing key of the system, which is only
10264 readable by the system administrator, it must be started as root; the
10265 @code{--user} option makes it drop root privileges early on.
10267 The signing key pair must be generated before @command{guix publish} is
10268 launched, using @command{guix archive --generate-key} (@pxref{Invoking
10271 The general syntax is:
10274 guix publish @var{options}@dots{}
10277 Running @command{guix publish} without any additional arguments will
10278 spawn an HTTP server on port 8080:
10284 Once a publishing server has been authorized (@pxref{Invoking guix
10285 archive}), the daemon may download substitutes from it:
10288 guix-daemon --substitute-urls=http://example.org:8080
10291 By default, @command{guix publish} compresses archives on the fly as it
10292 serves them. This ``on-the-fly'' mode is convenient in that it requires
10293 no setup and is immediately available. However, when serving lots of
10294 clients, we recommend using the @option{--cache} option, which enables
10295 caching of the archives before they are sent to clients---see below for
10296 details. The @command{guix weather} command provides a handy way to
10297 check what a server provides (@pxref{Invoking guix weather}).
10299 As a bonus, @command{guix publish} also serves as a content-addressed
10300 mirror for source files referenced in @code{origin} records
10301 (@pxref{origin Reference}). For instance, assuming @command{guix
10302 publish} is running on @code{example.org}, the following URL returns the
10303 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
10304 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
10307 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
10310 Obviously, these URLs only work for files that are in the store; in
10311 other cases, they return 404 (``Not Found'').
10313 @cindex build logs, publication
10314 Build logs are available from @code{/log} URLs like:
10317 http://example.org/log/gwspk@dots{}-guile-2.2.3
10321 When @command{guix-daemon} is configured to save compressed build logs,
10322 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
10323 URLs return the compressed log as-is, with an appropriate
10324 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
10325 running @command{guix-daemon} with @code{--log-compression=gzip} since
10326 Web browsers can automatically decompress it, which is not the case with
10329 The following options are available:
10332 @item --port=@var{port}
10333 @itemx -p @var{port}
10334 Listen for HTTP requests on @var{port}.
10336 @item --listen=@var{host}
10337 Listen on the network interface for @var{host}. The default is to
10338 accept connections from any interface.
10340 @item --user=@var{user}
10341 @itemx -u @var{user}
10342 Change privileges to @var{user} as soon as possible---i.e., once the
10343 server socket is open and the signing key has been read.
10345 @item --compression[=@var{method}[:@var{level}]]
10346 @itemx -C [@var{method}[:@var{level}]]
10347 Compress data using the given @var{method} and @var{level}. @var{method} is
10348 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
10351 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
10352 to different compression levels: 1 is the fastest, and 9 is the best
10353 (CPU-intensive). The default is 3.
10355 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
10356 increase in CPU usage; see
10357 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
10360 Unless @option{--cache} is used, compression occurs on the fly and
10361 the compressed streams are not
10362 cached. Thus, to reduce load on the machine that runs @command{guix
10363 publish}, it may be a good idea to choose a low compression level, to
10364 run @command{guix publish} behind a caching proxy, or to use
10365 @option{--cache}. Using @option{--cache} has the advantage that it
10366 allows @command{guix publish} to add @code{Content-Length} HTTP header
10369 This option can be repeated, in which case every substitute gets compressed
10370 using all the selected methods, and all of them are advertised. This is
10371 useful when users may not support all the compression methods: they can select
10372 the one they support.
10374 @item --cache=@var{directory}
10375 @itemx -c @var{directory}
10376 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
10377 and only serve archives that are in cache.
10379 When this option is omitted, archives and meta-data are created
10380 on-the-fly. This can reduce the available bandwidth, especially when
10381 compression is enabled, since this may become CPU-bound. Another
10382 drawback of the default mode is that the length of archives is not known
10383 in advance, so @command{guix publish} does not add a
10384 @code{Content-Length} HTTP header to its responses, which in turn
10385 prevents clients from knowing the amount of data being downloaded.
10387 Conversely, when @option{--cache} is used, the first request for a store
10388 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10389 background process to @dfn{bake} the archive---computing its
10390 @code{.narinfo} and compressing the archive, if needed. Once the
10391 archive is cached in @var{directory}, subsequent requests succeed and
10392 are served directly from the cache, which guarantees that clients get
10393 the best possible bandwidth.
10395 The ``baking'' process is performed by worker threads. By default, one
10396 thread per CPU core is created, but this can be customized. See
10397 @option{--workers} below.
10399 When @option{--ttl} is used, cached entries are automatically deleted
10400 when they have expired.
10402 @item --workers=@var{N}
10403 When @option{--cache} is used, request the allocation of @var{N} worker
10404 threads to ``bake'' archives.
10406 @item --ttl=@var{ttl}
10407 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10408 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10409 days, @code{1m} means 1 month, and so on.
10411 This allows the user's Guix to keep substitute information in cache for
10412 @var{ttl}. However, note that @code{guix publish} does not itself
10413 guarantee that the store items it provides will indeed remain available
10414 for as long as @var{ttl}.
10416 Additionally, when @option{--cache} is used, cached entries that have
10417 not been accessed for @var{ttl} and that no longer have a corresponding
10418 item in the store, may be deleted.
10420 @item --nar-path=@var{path}
10421 Use @var{path} as the prefix for the URLs of ``nar'' files
10422 (@pxref{Invoking guix archive, normalized archives}).
10424 By default, nars are served at a URL such as
10425 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
10426 change the @code{/nar} part to @var{path}.
10428 @item --public-key=@var{file}
10429 @itemx --private-key=@var{file}
10430 Use the specific @var{file}s as the public/private key pair used to sign
10431 the store items being published.
10433 The files must correspond to the same key pair (the private key is used
10434 for signing and the public key is merely advertised in the signature
10435 metadata). They must contain keys in the canonical s-expression format
10436 as produced by @command{guix archive --generate-key} (@pxref{Invoking
10437 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
10438 @file{/etc/guix/signing-key.sec} are used.
10440 @item --repl[=@var{port}]
10441 @itemx -r [@var{port}]
10442 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
10443 Reference Manual}) on @var{port} (37146 by default). This is used
10444 primarily for debugging a running @command{guix publish} server.
10447 Enabling @command{guix publish} on Guix System is a one-liner: just
10448 instantiate a @code{guix-publish-service-type} service in the @code{services} field
10449 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
10450 @code{guix-publish-service-type}}).
10452 If you are instead running Guix on a ``foreign distro'', follow these
10457 If your host distro uses the systemd init system:
10460 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
10461 /etc/systemd/system/
10462 # systemctl start guix-publish && systemctl enable guix-publish
10466 If your host distro uses the Upstart init system:
10469 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
10470 # start guix-publish
10474 Otherwise, proceed similarly with your distro's init system.
10477 @node Invoking guix challenge
10478 @section Invoking @command{guix challenge}
10480 @cindex reproducible builds
10481 @cindex verifiable builds
10482 @cindex @command{guix challenge}
10484 Do the binaries provided by this server really correspond to the source
10485 code it claims to build? Is a package build process deterministic?
10486 These are the questions the @command{guix challenge} command attempts to
10489 The former is obviously an important question: Before using a substitute
10490 server (@pxref{Substitutes}), one had better @emph{verify} that it
10491 provides the right binaries, and thus @emph{challenge} it. The latter
10492 is what enables the former: If package builds are deterministic, then
10493 independent builds of the package should yield the exact same result,
10494 bit for bit; if a server provides a binary different from the one
10495 obtained locally, it may be either corrupt or malicious.
10497 We know that the hash that shows up in @file{/gnu/store} file names is
10498 the hash of all the inputs of the process that built the file or
10499 directory---compilers, libraries, build scripts,
10500 etc. (@pxref{Introduction}). Assuming deterministic build processes,
10501 one store file name should map to exactly one build output.
10502 @command{guix challenge} checks whether there is, indeed, a single
10503 mapping by comparing the build outputs of several independent builds of
10504 any given store item.
10506 The command output looks like this:
10509 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10510 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
10511 updating list of substitutes from 'https://guix.example.org'... 100.0%
10512 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
10513 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10514 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10515 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
10517 /lib/libcrypto.so.1.1
10520 /gnu/store/@dots{}-git-2.5.0 contents differ:
10521 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
10522 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
10523 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
10525 /libexec/git-core/git-fsck
10527 /gnu/store/@dots{}-pius-2.1.1 contents differ:
10528 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10529 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10530 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
10532 /share/man/man1/pius.1.gz
10536 6,406 store items were analyzed:
10537 - 4,749 (74.1%) were identical
10538 - 525 (8.2%) differed
10539 - 1,132 (17.7%) were inconclusive
10543 In this example, @command{guix challenge} first scans the store to
10544 determine the set of locally-built derivations---as opposed to store
10545 items that were downloaded from a substitute server---and then queries
10546 all the substitute servers. It then reports those store items for which
10547 the servers obtained a result different from the local build.
10549 @cindex non-determinism, in package builds
10550 As an example, @code{guix.example.org} always gets a different answer.
10551 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10552 case of Git. This might indicate that the build process of Git is
10553 non-deterministic, meaning that its output varies as a function of
10554 various things that Guix does not fully control, in spite of building
10555 packages in isolated environments (@pxref{Features}). Most common
10556 sources of non-determinism include the addition of timestamps in build
10557 results, the inclusion of random numbers, and directory listings sorted
10558 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
10561 To find out what is wrong with this Git binary, the easiest approach is
10565 guix challenge git \
10566 --diff=diffoscope \
10567 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10570 This automatically invokes @command{diffoscope}, which displays detailed
10571 information about files that differ.
10573 Alternately, we can do something along these lines (@pxref{Invoking guix
10577 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
10578 | lzip -d | guix archive -x /tmp/git
10579 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
10582 This command shows the difference between the files resulting from the
10583 local build, and the files resulting from the build on
10584 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
10585 diffutils, Comparing and Merging Files}). The @command{diff} command
10586 works great for text files. When binary files differ, a better option
10587 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
10588 visualize differences for all kinds of files.
10590 Once you have done that work, you can tell whether the differences are due
10591 to a non-deterministic build process or to a malicious server. We try
10592 hard to remove sources of non-determinism in packages to make it easier
10593 to verify substitutes, but of course, this is a process that
10594 involves not just Guix, but a large part of the free software community.
10595 In the meantime, @command{guix challenge} is one tool to help address
10598 If you are writing packages for Guix, you are encouraged to check
10599 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
10600 same build result as you did with:
10603 $ guix challenge @var{package}
10607 where @var{package} is a package specification such as
10608 @code{guile@@2.0} or @code{glibc:debug}.
10610 The general syntax is:
10613 guix challenge @var{options} [@var{packages}@dots{}]
10616 When a difference is found between the hash of a locally-built item and
10617 that of a server-provided substitute, or among substitutes provided by
10618 different servers, the command displays it as in the example above and
10619 its exit code is 2 (other non-zero exit codes denote other kinds of
10622 The one option that matters is:
10626 @item --substitute-urls=@var{urls}
10627 Consider @var{urls} the whitespace-separated list of substitute source
10628 URLs to compare to.
10630 @item --diff=@var{mode}
10631 Upon mismatches, show differences according to @var{mode}, one of:
10634 @item @code{simple} (the default)
10635 Show the list of files that differ.
10637 @item @code{diffoscope}
10638 @itemx @var{command}
10639 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
10640 two directories whose contents do not match.
10642 When @var{command} is an absolute file name, run @var{command} instead
10646 Do not show further details about the differences.
10649 Thus, unless @code{--diff=none} is passed, @command{guix challenge}
10650 downloads the store items from the given substitute servers so that it
10655 Show details about matches (identical contents) in addition to
10656 information about mismatches.
10660 @node Invoking guix copy
10661 @section Invoking @command{guix copy}
10663 @cindex copy, of store items, over SSH
10664 @cindex SSH, copy of store items
10665 @cindex sharing store items across machines
10666 @cindex transferring store items across machines
10667 The @command{guix copy} command copies items from the store of one
10668 machine to that of another machine over a secure shell (SSH)
10669 connection@footnote{This command is available only when Guile-SSH was
10670 found. @xref{Requirements}, for details.}. For example, the following
10671 command copies the @code{coreutils} package, the user's profile, and all
10672 their dependencies over to @var{host}, logged in as @var{user}:
10675 guix copy --to=@var{user}@@@var{host} \
10676 coreutils `readlink -f ~/.guix-profile`
10679 If some of the items to be copied are already present on @var{host},
10680 they are not actually sent.
10682 The command below retrieves @code{libreoffice} and @code{gimp} from
10683 @var{host}, assuming they are available there:
10686 guix copy --from=@var{host} libreoffice gimp
10689 The SSH connection is established using the Guile-SSH client, which is
10690 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10691 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10693 The key used to sign items that are sent must be accepted by the remote
10694 machine. Likewise, the key used by the remote machine to sign items you
10695 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10696 own daemon. @xref{Invoking guix archive}, for more information about
10697 store item authentication.
10699 The general syntax is:
10702 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10705 You must always specify one of the following options:
10708 @item --to=@var{spec}
10709 @itemx --from=@var{spec}
10710 Specify the host to send to or receive from. @var{spec} must be an SSH
10711 spec such as @code{example.org}, @code{charlie@@example.org}, or
10712 @code{charlie@@example.org:2222}.
10715 The @var{items} can be either package names, such as @code{gimp}, or
10716 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10718 When specifying the name of a package to send, it is first built if
10719 needed, unless @option{--dry-run} was specified. Common build options
10720 are supported (@pxref{Common Build Options}).
10723 @node Invoking guix container
10724 @section Invoking @command{guix container}
10726 @cindex @command{guix container}
10728 As of version @value{VERSION}, this tool is experimental. The interface
10729 is subject to radical change in the future.
10732 The purpose of @command{guix container} is to manipulate processes
10733 running within an isolated environment, commonly known as a
10734 ``container'', typically created by the @command{guix environment}
10735 (@pxref{Invoking guix environment}) and @command{guix system container}
10736 (@pxref{Invoking guix system}) commands.
10738 The general syntax is:
10741 guix container @var{action} @var{options}@dots{}
10744 @var{action} specifies the operation to perform with a container, and
10745 @var{options} specifies the context-specific arguments for the action.
10747 The following actions are available:
10751 Execute a command within the context of a running container.
10756 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10759 @var{pid} specifies the process ID of the running container.
10760 @var{program} specifies an executable file name within the root file
10761 system of the container. @var{arguments} are the additional options that
10762 will be passed to @var{program}.
10764 The following command launches an interactive login shell inside a
10765 Guix system container, started by @command{guix system container}, and whose
10766 process ID is 9001:
10769 guix container exec 9001 /run/current-system/profile/bin/bash --login
10772 Note that the @var{pid} cannot be the parent process of a container. It
10773 must be PID 1 of the container or one of its child processes.
10777 @node Invoking guix weather
10778 @section Invoking @command{guix weather}
10780 Occasionally you're grumpy because substitutes are lacking and you end
10781 up building packages by yourself (@pxref{Substitutes}). The
10782 @command{guix weather} command reports on substitute availability on the
10783 specified servers so you can have an idea of whether you'll be grumpy
10784 today. It can sometimes be useful info as a user, but it is primarily
10785 useful to people running @command{guix publish} (@pxref{Invoking guix
10788 @cindex statistics, for substitutes
10789 @cindex availability of substitutes
10790 @cindex substitute availability
10791 @cindex weather, substitute availability
10792 Here's a sample run:
10795 $ guix weather --substitute-urls=https://guix.example.org
10796 computing 5,872 package derivations for x86_64-linux...
10797 looking for 6,128 store items on https://guix.example.org..
10798 updating list of substitutes from 'https://guix.example.org'... 100.0%
10799 https://guix.example.org
10800 43.4% substitutes available (2,658 out of 6,128)
10801 7,032.5 MiB of nars (compressed)
10802 19,824.2 MiB on disk (uncompressed)
10803 0.030 seconds per request (182.9 seconds in total)
10804 33.5 requests per second
10806 9.8% (342 out of 3,470) of the missing items are queued
10808 x86_64-linux: 518 (59.7%)
10809 i686-linux: 221 (25.5%)
10810 aarch64-linux: 128 (14.8%)
10811 build rate: 23.41 builds per hour
10812 x86_64-linux: 11.16 builds per hour
10813 i686-linux: 6.03 builds per hour
10814 aarch64-linux: 6.41 builds per hour
10817 @cindex continuous integration, statistics
10818 As you can see, it reports the fraction of all the packages for which
10819 substitutes are available on the server---regardless of whether
10820 substitutes are enabled, and regardless of whether this server's signing
10821 key is authorized. It also reports the size of the compressed archives
10822 (``nars'') provided by the server, the size the corresponding store
10823 items occupy in the store (assuming deduplication is turned off), and
10824 the server's throughput. The second part gives continuous integration
10825 (CI) statistics, if the server supports it. In addition, using the
10826 @option{--coverage} option, @command{guix weather} can list ``important''
10827 package substitutes missing on the server (see below).
10829 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10830 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10831 challenge}, it ignores signatures on those substitutes, which is
10832 innocuous since the command only gathers statistics and cannot install
10835 The general syntax is:
10838 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10841 When @var{packages} is omitted, @command{guix weather} checks the availability
10842 of substitutes for @emph{all} the packages, or for those specified with
10843 @option{--manifest}; otherwise it only considers the specified packages. It
10844 is also possible to query specific system types with @option{--system}.
10845 @command{guix weather} exits with a non-zero code when the fraction of
10846 available substitutes is below 100%.
10848 The available options are listed below.
10851 @item --substitute-urls=@var{urls}
10852 @var{urls} is the space-separated list of substitute server URLs to
10853 query. When this option is omitted, the default set of substitute
10854 servers is queried.
10856 @item --system=@var{system}
10857 @itemx -s @var{system}
10858 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10859 option can be repeated, in which case @command{guix weather} will query
10860 substitutes for several system types.
10862 @item --manifest=@var{file}
10863 Instead of querying substitutes for all the packages, only ask for those
10864 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10865 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10868 This option can be repeated several times, in which case the manifests
10871 @item --coverage[=@var{count}]
10872 @itemx -c [@var{count}]
10873 Report on substitute coverage for packages: list packages with at least
10874 @var{count} dependents (zero by default) for which substitutes are
10875 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10876 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10877 @var{b} usually lacks substitutes as well. The result looks like this:
10880 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10881 computing 8,983 package derivations for x86_64-linux...
10882 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10883 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10884 @value{SUBSTITUTE-URL}
10885 64.7% substitutes available (6,047 out of 9,343)
10887 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10888 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10889 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10890 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10894 What this example shows is that @code{kcoreaddons} and presumably the 58
10895 packages that depend on it have no substitutes at @code{ci.guix.info};
10896 likewise for @code{qgpgme} and the 46 packages that depend on it.
10898 If you are a Guix developer, or if you are taking care of this build farm,
10899 you'll probably want to have a closer look at these packages: they may simply
10902 @item --display-missing
10903 Display the list of store items for which substitutes are missing.
10906 @node Invoking guix processes
10907 @section Invoking @command{guix processes}
10909 The @command{guix processes} command can be useful to developers and system
10910 administrators, especially on multi-user machines and on build farms: it lists
10911 the current sessions (connections to the daemon), as well as information about
10912 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10913 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10914 listed.}. Here's an example of the information it returns:
10917 $ sudo guix processes
10920 ClientCommand: guix environment --ad-hoc python
10924 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10928 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10929 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10930 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10931 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10932 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10933 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10934 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10937 In this example we see that @command{guix-daemon} has three clients:
10938 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10939 integration tool; their process identifier (PID) is given by the
10940 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10941 @command{guix-daemon} sub-process of this particular session.
10943 The @code{LockHeld} fields show which store items are currently locked by this
10944 session, which corresponds to store items being built or substituted (the
10945 @code{LockHeld} field is not displayed when @command{guix processes} is not
10946 running as root.) Last, by looking at the @code{ChildProcess} field, we
10947 understand that these three builds are being offloaded (@pxref{Daemon Offload
10950 The output is in Recutils format so we can use the handy @command{recsel}
10951 command to select sessions of interest (@pxref{Selection Expressions,,,
10952 recutils, GNU recutils manual}). As an example, the command shows the command
10953 line and PID of the client that triggered the build of a Perl package:
10956 $ sudo guix processes | \
10957 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10959 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10962 @node System Configuration
10963 @chapter System Configuration
10965 @cindex system configuration
10966 Guix System supports a consistent whole-system configuration
10967 mechanism. By that we mean that all aspects of the global system
10968 configuration---such as the available system services, timezone and
10969 locale settings, user accounts---are declared in a single place. Such
10970 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10972 One of the advantages of putting all the system configuration under the
10973 control of Guix is that it supports transactional system upgrades, and
10974 makes it possible to roll back to a previous system instantiation,
10975 should something go wrong with the new one (@pxref{Features}). Another
10976 advantage is that it makes it easy to replicate the exact same configuration
10977 across different machines, or at different points in time, without
10978 having to resort to additional administration tools layered on top of
10979 the own tools of the system.
10980 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10982 This section describes this mechanism. First we focus on the system
10983 administrator's viewpoint---explaining how the system is configured and
10984 instantiated. Then we show how this mechanism can be extended, for
10985 instance to support new system services.
10988 * Using the Configuration System:: Customizing your GNU system.
10989 * operating-system Reference:: Detail of operating-system declarations.
10990 * File Systems:: Configuring file system mounts.
10991 * Mapped Devices:: Block device extra processing.
10992 * User Accounts:: Specifying user accounts.
10993 * Keyboard Layout:: How the system interprets key strokes.
10994 * Locales:: Language and cultural convention settings.
10995 * Services:: Specifying system services.
10996 * Setuid Programs:: Programs running with root privileges.
10997 * X.509 Certificates:: Authenticating HTTPS servers.
10998 * Name Service Switch:: Configuring libc's name service switch.
10999 * Initial RAM Disk:: Linux-Libre bootstrapping.
11000 * Bootloader Configuration:: Configuring the boot loader.
11001 * Invoking guix system:: Instantiating a system configuration.
11002 * Invoking guix deploy:: Deploying a system configuration to a remote host.
11003 * Running Guix in a VM:: How to run Guix System in a virtual machine.
11004 * Defining Services:: Adding new service definitions.
11007 @node Using the Configuration System
11008 @section Using the Configuration System
11010 The operating system is configured by providing an
11011 @code{operating-system} declaration in a file that can then be passed to
11012 the @command{guix system} command (@pxref{Invoking guix system}). A
11013 simple setup, with the default system services, the default Linux-Libre
11014 kernel, initial RAM disk, and boot loader looks like this:
11016 @findex operating-system
11018 @include os-config-bare-bones.texi
11021 This example should be self-describing. Some of the fields defined
11022 above, such as @code{host-name} and @code{bootloader}, are mandatory.
11023 Others, such as @code{packages} and @code{services}, can be omitted, in
11024 which case they get a default value.
11026 Below we discuss the effect of some of the most important fields
11027 (@pxref{operating-system Reference}, for details about all the available
11028 fields), and how to @dfn{instantiate} the operating system using
11029 @command{guix system}.
11031 @unnumberedsubsec Bootloader
11033 @cindex legacy boot, on Intel machines
11034 @cindex BIOS boot, on Intel machines
11037 The @code{bootloader} field describes the method that will be used to boot
11038 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
11039 mode, as in the example above. However, more recent machines rely instead on
11040 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
11041 the @code{bootloader} field should contain something along these lines:
11044 (bootloader-configuration
11045 (bootloader grub-efi-bootloader)
11046 (target "/boot/efi"))
11049 @xref{Bootloader Configuration}, for more information on the available
11050 configuration options.
11052 @unnumberedsubsec Globally-Visible Packages
11054 @vindex %base-packages
11055 The @code{packages} field lists packages that will be globally visible
11056 on the system, for all user accounts---i.e., in every user's @code{PATH}
11057 environment variable---in addition to the per-user profiles
11058 (@pxref{Invoking guix package}). The @code{%base-packages} variable
11059 provides all the tools one would expect for basic user and administrator
11060 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
11061 the GNU Zile lightweight text editor, @command{find}, @command{grep},
11062 etc. The example above adds GNU@tie{}Screen to those,
11063 taken from the @code{(gnu packages screen)}
11064 module (@pxref{Package Modules}). The
11065 @code{(list package output)} syntax can be used to add a specific output
11069 (use-modules (gnu packages))
11070 (use-modules (gnu packages dns))
11074 (packages (cons (list bind "utils")
11078 @findex specification->package
11079 Referring to packages by variable name, like @code{bind} above, has
11080 the advantage of being unambiguous; it also allows typos and such to be
11081 diagnosed right away as ``unbound variables''. The downside is that one
11082 needs to know which module defines which package, and to augment the
11083 @code{use-package-modules} line accordingly. To avoid that, one can use
11084 the @code{specification->package} procedure of the @code{(gnu packages)}
11085 module, which returns the best package for a given name or name and
11089 (use-modules (gnu packages))
11093 (packages (append (map specification->package
11094 '("tcpdump" "htop" "gnupg@@2.0"))
11098 @unnumberedsubsec System Services
11101 @vindex %base-services
11102 The @code{services} field lists @dfn{system services} to be made
11103 available when the system starts (@pxref{Services}).
11104 The @code{operating-system} declaration above specifies that, in
11105 addition to the basic services, we want the OpenSSH secure shell
11106 daemon listening on port 2222 (@pxref{Networking Services,
11107 @code{openssh-service-type}}). Under the hood,
11108 @code{openssh-service-type} arranges so that @command{sshd} is started with the
11109 right command-line options, possibly with supporting configuration files
11110 generated as needed (@pxref{Defining Services}).
11112 @cindex customization, of services
11113 @findex modify-services
11114 Occasionally, instead of using the base services as is, you will want to
11115 customize them. To do this, use @code{modify-services} (@pxref{Service
11116 Reference, @code{modify-services}}) to modify the list.
11118 For example, suppose you want to modify @code{guix-daemon} and Mingetty
11119 (the console log-in) in the @code{%base-services} list (@pxref{Base
11120 Services, @code{%base-services}}). To do that, you can write the
11121 following in your operating system declaration:
11124 (define %my-services
11125 ;; My very own list of services.
11126 (modify-services %base-services
11127 (guix-service-type config =>
11128 (guix-configuration
11130 (use-substitutes? #f)
11131 (extra-options '("--gc-keep-derivations"))))
11132 (mingetty-service-type config =>
11133 (mingetty-configuration
11134 (inherit config)))))
11138 (services %my-services))
11141 This changes the configuration---i.e., the service parameters---of the
11142 @code{guix-service-type} instance, and that of all the
11143 @code{mingetty-service-type} instances in the @code{%base-services} list.
11144 Observe how this is accomplished: first, we arrange for the original
11145 configuration to be bound to the identifier @code{config} in the
11146 @var{body}, and then we write the @var{body} so that it evaluates to the
11147 desired configuration. In particular, notice how we use @code{inherit}
11148 to create a new configuration which has the same values as the old
11149 configuration, but with a few modifications.
11151 @cindex encrypted disk
11152 The configuration for a typical ``desktop'' usage, with an encrypted
11153 root partition, the X11 display
11154 server, GNOME and Xfce (users can choose which of these desktop
11155 environments to use at the log-in screen by pressing @kbd{F1}), network
11156 management, power management, and more, would look like this:
11159 @include os-config-desktop.texi
11162 A graphical system with a choice of lightweight window managers
11163 instead of full-blown desktop environments would look like this:
11166 @include os-config-lightweight-desktop.texi
11169 This example refers to the @file{/boot/efi} file system by its UUID,
11170 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
11171 as returned by the @command{blkid} command.
11173 @xref{Desktop Services}, for the exact list of services provided by
11174 @code{%desktop-services}. @xref{X.509 Certificates}, for background
11175 information about the @code{nss-certs} package that is used here.
11177 Again, @code{%desktop-services} is just a list of service objects. If
11178 you want to remove services from there, you can do so using the
11179 procedures for list filtering (@pxref{SRFI-1 Filtering and
11180 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
11181 following expression returns a list that contains all the services in
11182 @code{%desktop-services} minus the Avahi service:
11185 (remove (lambda (service)
11186 (eq? (service-kind service) avahi-service-type))
11190 @unnumberedsubsec Instantiating the System
11192 Assuming the @code{operating-system} declaration
11193 is stored in the @file{my-system-config.scm}
11194 file, the @command{guix system reconfigure my-system-config.scm} command
11195 instantiates that configuration, and makes it the default GRUB boot
11196 entry (@pxref{Invoking guix system}).
11198 The normal way to change the system configuration is by updating this
11199 file and re-running @command{guix system reconfigure}. One should never
11200 have to touch files in @file{/etc} or to run commands that modify the
11201 system state such as @command{useradd} or @command{grub-install}. In
11202 fact, you must avoid that since that would not only void your warranty
11203 but also prevent you from rolling back to previous versions of your
11204 system, should you ever need to.
11206 @cindex roll-back, of the operating system
11207 Speaking of roll-back, each time you run @command{guix system
11208 reconfigure}, a new @dfn{generation} of the system is created---without
11209 modifying or deleting previous generations. Old system generations get
11210 an entry in the bootloader boot menu, allowing you to boot them in case
11211 something went wrong with the latest generation. Reassuring, no? The
11212 @command{guix system list-generations} command lists the system
11213 generations available on disk. It is also possible to roll back the
11214 system via the commands @command{guix system roll-back} and
11215 @command{guix system switch-generation}.
11217 Although the @command{guix system reconfigure} command will not modify
11218 previous generations, you must take care when the current generation is not
11219 the latest (e.g., after invoking @command{guix system roll-back}), since
11220 the operation might overwrite a later generation (@pxref{Invoking guix
11223 @unnumberedsubsec The Programming Interface
11225 At the Scheme level, the bulk of an @code{operating-system} declaration
11226 is instantiated with the following monadic procedure (@pxref{The Store
11229 @deffn {Monadic Procedure} operating-system-derivation os
11230 Return a derivation that builds @var{os}, an @code{operating-system}
11231 object (@pxref{Derivations}).
11233 The output of the derivation is a single directory that refers to all
11234 the packages, configuration files, and other supporting files needed to
11235 instantiate @var{os}.
11238 This procedure is provided by the @code{(gnu system)} module. Along
11239 with @code{(gnu services)} (@pxref{Services}), this module contains the
11240 guts of Guix System. Make sure to visit it!
11243 @node operating-system Reference
11244 @section @code{operating-system} Reference
11246 This section summarizes all the options available in
11247 @code{operating-system} declarations (@pxref{Using the Configuration
11250 @deftp {Data Type} operating-system
11251 This is the data type representing an operating system configuration.
11252 By that, we mean all the global system configuration, not per-user
11253 configuration (@pxref{Using the Configuration System}).
11256 @item @code{kernel} (default: @code{linux-libre})
11257 The package object of the operating system kernel to use@footnote{Currently
11258 only the Linux-libre kernel is supported. In the future, it will be
11259 possible to use the GNU@tie{}Hurd.}.
11261 @item @code{kernel-loadable-modules} (default: '())
11262 A list of objects (usually packages) to collect loadable kernel modules
11263 from--e.g. @code{(list ddcci-driver-linux)}.
11265 @item @code{kernel-arguments} (default: @code{'("quiet")})
11266 List of strings or gexps representing additional arguments to pass on
11267 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
11269 @item @code{bootloader}
11270 The system bootloader configuration object. @xref{Bootloader Configuration}.
11273 This is the label (a string) as it appears in the bootloader's menu entry.
11274 The default label includes the kernel name and version.
11276 @item @code{keyboard-layout} (default: @code{#f})
11277 This field specifies the keyboard layout to use in the console. It can be
11278 either @code{#f}, in which case the default keyboard layout is used (usually
11279 US English), or a @code{<keyboard-layout>} record.
11281 This keyboard layout is in effect as soon as the kernel has booted. For
11282 instance, it is the keyboard layout in effect when you type a passphrase if
11283 your root file system is on a @code{luks-device-mapping} mapped device
11284 (@pxref{Mapped Devices}).
11287 This does @emph{not} specify the keyboard layout used by the bootloader, nor
11288 that used by the graphical display server. @xref{Bootloader Configuration},
11289 for information on how to specify the bootloader's keyboard layout. @xref{X
11290 Window}, for information on how to specify the keyboard layout used by the X
11294 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
11296 @cindex initial RAM disk
11297 The list of Linux kernel modules that need to be available in the
11298 initial RAM disk. @xref{Initial RAM Disk}.
11300 @item @code{initrd} (default: @code{base-initrd})
11301 A procedure that returns an initial RAM disk for the Linux
11302 kernel. This field is provided to support low-level customization and
11303 should rarely be needed for casual use. @xref{Initial RAM Disk}.
11305 @item @code{firmware} (default: @code{%base-firmware})
11307 List of firmware packages loadable by the operating system kernel.
11309 The default includes firmware needed for Atheros- and Broadcom-based
11310 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
11311 respectively). @xref{Hardware Considerations}, for more info on
11312 supported hardware.
11314 @item @code{host-name}
11317 @item @code{hosts-file}
11319 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
11320 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
11321 Reference Manual}). The default is a file with entries for
11322 @code{localhost} and @var{host-name}.
11324 @item @code{mapped-devices} (default: @code{'()})
11325 A list of mapped devices. @xref{Mapped Devices}.
11327 @item @code{file-systems}
11328 A list of file systems. @xref{File Systems}.
11330 @item @code{swap-devices} (default: @code{'()})
11331 @cindex swap devices
11332 A list of strings identifying devices or files to be used for ``swap
11333 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
11334 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
11335 It is possible to specify a swap file in a file system on a mapped
11336 device, provided that the necessary device mapping and file system are
11337 also specified. @xref{Mapped Devices} and @ref{File Systems}.
11339 @item @code{users} (default: @code{%base-user-accounts})
11340 @itemx @code{groups} (default: @code{%base-groups})
11341 List of user accounts and groups. @xref{User Accounts}.
11343 If the @code{users} list lacks a user account with UID@tie{}0, a
11344 ``root'' account with UID@tie{}0 is automatically added.
11346 @item @code{skeletons} (default: @code{(default-skeletons)})
11347 A list target file name/file-like object tuples (@pxref{G-Expressions,
11348 file-like objects}). These are the skeleton files that will be added to
11349 the home directory of newly-created user accounts.
11351 For instance, a valid value may look like this:
11354 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
11355 (".guile" ,(plain-file "guile"
11356 "(use-modules (ice-9 readline))
11357 (activate-readline)")))
11360 @item @code{issue} (default: @code{%default-issue})
11361 A string denoting the contents of the @file{/etc/issue} file, which is
11362 displayed when users log in on a text console.
11364 @item @code{packages} (default: @code{%base-packages})
11365 The set of packages installed in the global profile, which is accessible
11366 at @file{/run/current-system/profile}.
11368 The default set includes core utilities and it is good practice to
11369 install non-core utilities in user profiles (@pxref{Invoking guix
11372 @item @code{timezone}
11373 A timezone identifying string---e.g., @code{"Europe/Paris"}.
11375 You can run the @command{tzselect} command to find out which timezone
11376 string corresponds to your region. Choosing an invalid timezone name
11377 causes @command{guix system} to fail.
11379 @item @code{locale} (default: @code{"en_US.utf8"})
11380 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
11381 Library Reference Manual}). @xref{Locales}, for more information.
11383 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
11384 The list of locale definitions to be compiled and that may be used at
11385 run time. @xref{Locales}.
11387 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
11388 The list of GNU@tie{}libc packages whose locale data and tools are used
11389 to build the locale definitions. @xref{Locales}, for compatibility
11390 considerations that justify this option.
11392 @item @code{name-service-switch} (default: @code{%default-nss})
11393 Configuration of the libc name service switch (NSS)---a
11394 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
11397 @item @code{services} (default: @code{%base-services})
11398 A list of service objects denoting system services. @xref{Services}.
11400 @cindex essential services
11401 @item @code{essential-services} (default: ...)
11402 The list of ``essential services''---i.e., things like instances of
11403 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
11404 Reference}), which are derived from the operating system definition itself.
11405 As a user you should @emph{never} need to touch this field.
11407 @item @code{pam-services} (default: @code{(base-pam-services)})
11409 @cindex pluggable authentication modules
11410 Linux @dfn{pluggable authentication module} (PAM) services.
11411 @c FIXME: Add xref to PAM services section.
11413 @item @code{setuid-programs} (default: @code{%setuid-programs})
11414 List of string-valued G-expressions denoting setuid programs.
11415 @xref{Setuid Programs}.
11417 @item @code{sudoers-file} (default: @code{%sudoers-specification})
11418 @cindex sudoers file
11419 The contents of the @file{/etc/sudoers} file as a file-like object
11420 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
11422 This file specifies which users can use the @command{sudo} command, what
11423 they are allowed to do, and what privileges they may gain. The default
11424 is that only @code{root} and members of the @code{wheel} group may use
11429 @deffn {Scheme Syntax} this-operating-system
11430 When used in the @emph{lexical scope} of an operating system field definition,
11431 this identifier resolves to the operating system being defined.
11433 The example below shows how to refer to the operating system being defined in
11434 the definition of the @code{label} field:
11437 (use-modules (gnu) (guix))
11441 (label (package-full-name
11442 (operating-system-kernel this-operating-system))))
11445 It is an error to refer to @code{this-operating-system} outside an operating
11452 @section File Systems
11454 The list of file systems to be mounted is specified in the
11455 @code{file-systems} field of the operating system declaration
11456 (@pxref{Using the Configuration System}). Each file system is declared
11457 using the @code{file-system} form, like this:
11461 (mount-point "/home")
11462 (device "/dev/sda3")
11466 As usual, some of the fields are mandatory---those shown in the example
11467 above---while others can be omitted. These are described below.
11469 @deftp {Data Type} file-system
11470 Objects of this type represent file systems to be mounted. They
11471 contain the following members:
11475 This is a string specifying the type of the file system---e.g.,
11478 @item @code{mount-point}
11479 This designates the place where the file system is to be mounted.
11481 @item @code{device}
11482 This names the ``source'' of the file system. It can be one of three
11483 things: a file system label, a file system UUID, or the name of a
11484 @file{/dev} node. Labels and UUIDs offer a way to refer to file
11485 systems without having to hard-code their actual device
11486 name@footnote{Note that, while it is tempting to use
11487 @file{/dev/disk/by-uuid} and similar device names to achieve the same
11488 result, this is not recommended: These special device nodes are created
11489 by the udev daemon and may be unavailable at the time the device is
11492 @findex file-system-label
11493 File system labels are created using the @code{file-system-label}
11494 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
11495 plain strings. Here's an example of a file system referred to by its
11496 label, as shown by the @command{e2label} command:
11500 (mount-point "/home")
11502 (device (file-system-label "my-home")))
11506 UUIDs are converted from their string representation (as shown by the
11507 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
11508 @code{uuid} form expects 16-byte UUIDs as defined in
11509 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
11510 form of UUID used by the ext2 family of file systems and others, but it
11511 is different from ``UUIDs'' found in FAT file systems, for instance.},
11516 (mount-point "/home")
11518 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
11521 When the source of a file system is a mapped device (@pxref{Mapped
11522 Devices}), its @code{device} field @emph{must} refer to the mapped
11523 device name---e.g., @file{"/dev/mapper/root-partition"}.
11524 This is required so that
11525 the system knows that mounting the file system depends on having the
11526 corresponding device mapping established.
11528 @item @code{flags} (default: @code{'()})
11529 This is a list of symbols denoting mount flags. Recognized flags
11530 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
11531 access to special files), @code{no-suid} (ignore setuid and setgid
11532 bits), @code{no-atime} (do not update file access times),
11533 @code{strict-atime} (update file access time), @code{lazy-time} (only
11534 update time on the in-memory version of the file inode), and
11535 @code{no-exec} (disallow program execution).
11536 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
11537 Manual}, for more information on these flags.
11539 @item @code{options} (default: @code{#f})
11540 This is either @code{#f}, or a string denoting mount options passed to the
11541 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
11542 Reference Manual}, for details and run @command{man 8 mount} for options for
11543 various file systems.
11545 @item @code{mount?} (default: @code{#t})
11546 This value indicates whether to automatically mount the file system when
11547 the system is brought up. When set to @code{#f}, the file system gets
11548 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
11549 is not automatically mounted.
11551 @item @code{needed-for-boot?} (default: @code{#f})
11552 This Boolean value indicates whether the file system is needed when
11553 booting. If that is true, then the file system is mounted when the
11554 initial RAM disk (initrd) is loaded. This is always the case, for
11555 instance, for the root file system.
11557 @item @code{check?} (default: @code{#t})
11558 This Boolean indicates whether the file system needs to be checked for
11559 errors before being mounted.
11561 @item @code{create-mount-point?} (default: @code{#f})
11562 When true, the mount point is created if it does not exist yet.
11564 @item @code{dependencies} (default: @code{'()})
11565 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
11566 representing file systems that must be mounted or mapped devices that
11567 must be opened before (and unmounted or closed after) this one.
11569 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
11570 a dependency of @file{/sys/fs/cgroup/cpu} and
11571 @file{/sys/fs/cgroup/memory}.
11573 Another example is a file system that depends on a mapped device, for
11574 example for an encrypted partition (@pxref{Mapped Devices}).
11578 The @code{(gnu system file-systems)} exports the following useful
11581 @defvr {Scheme Variable} %base-file-systems
11582 These are essential file systems that are required on normal systems,
11583 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
11584 below.) Operating system declarations should always contain at least
11588 @defvr {Scheme Variable} %pseudo-terminal-file-system
11589 This is the file system to be mounted as @file{/dev/pts}. It supports
11590 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
11591 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
11592 Manual}). Pseudo-terminals are used by terminal emulators such as
11596 @defvr {Scheme Variable} %shared-memory-file-system
11597 This file system is mounted as @file{/dev/shm} and is used to support
11598 memory sharing across processes (@pxref{Memory-mapped I/O,
11599 @code{shm_open},, libc, The GNU C Library Reference Manual}).
11602 @defvr {Scheme Variable} %immutable-store
11603 This file system performs a read-only ``bind mount'' of
11604 @file{/gnu/store}, making it read-only for all the users including
11605 @code{root}. This prevents against accidental modification by software
11606 running as @code{root} or by system administrators.
11608 The daemon itself is still able to write to the store: it remounts it
11609 read-write in its own ``name space.''
11612 @defvr {Scheme Variable} %binary-format-file-system
11613 The @code{binfmt_misc} file system, which allows handling of arbitrary
11614 executable file types to be delegated to user space. This requires the
11615 @code{binfmt.ko} kernel module to be loaded.
11618 @defvr {Scheme Variable} %fuse-control-file-system
11619 The @code{fusectl} file system, which allows unprivileged users to mount
11620 and unmount user-space FUSE file systems. This requires the
11621 @code{fuse.ko} kernel module to be loaded.
11624 @node Mapped Devices
11625 @section Mapped Devices
11627 @cindex device mapping
11628 @cindex mapped devices
11629 The Linux kernel has a notion of @dfn{device mapping}: a block device,
11630 such as a hard disk partition, can be @dfn{mapped} into another device,
11631 usually in @code{/dev/mapper/},
11632 with additional processing over the data that flows through
11633 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
11634 concept of a ``mapped device'' and that of a file system: both boil down
11635 to @emph{translating} input/output operations made on a file to
11636 operations on its backing store. Thus, the Hurd implements mapped
11637 devices, like file systems, using the generic @dfn{translator} mechanism
11638 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
11639 typical example is encryption device mapping: all writes to the mapped
11640 device are encrypted, and all reads are deciphered, transparently.
11641 Guix extends this notion by considering any device or set of devices that
11642 are @dfn{transformed} in some way to create a new device; for instance,
11643 RAID devices are obtained by @dfn{assembling} several other devices, such
11644 as hard disks or partitions, into a new one that behaves as one partition.
11645 Other examples, not yet implemented, are LVM logical volumes.
11647 Mapped devices are declared using the @code{mapped-device} form,
11648 defined as follows; for examples, see below.
11650 @deftp {Data Type} mapped-device
11651 Objects of this type represent device mappings that will be made when
11652 the system boots up.
11656 This is either a string specifying the name of the block device to be mapped,
11657 such as @code{"/dev/sda3"}, or a list of such strings when several devices
11658 need to be assembled for creating a new one.
11661 This string specifies the name of the resulting mapped device. For
11662 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
11663 specifying @code{"my-partition"} leads to the creation of
11664 the @code{"/dev/mapper/my-partition"} device.
11665 For RAID devices of type @code{raid-device-mapping}, the full device name
11666 such as @code{"/dev/md0"} needs to be given.
11669 This must be a @code{mapped-device-kind} object, which specifies how
11670 @var{source} is mapped to @var{target}.
11674 @defvr {Scheme Variable} luks-device-mapping
11675 This defines LUKS block device encryption using the @command{cryptsetup}
11676 command from the package with the same name. It relies on the
11677 @code{dm-crypt} Linux kernel module.
11680 @defvr {Scheme Variable} raid-device-mapping
11681 This defines a RAID device, which is assembled using the @code{mdadm}
11682 command from the package with the same name. It requires a Linux kernel
11683 module for the appropriate RAID level to be loaded, such as @code{raid456}
11684 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
11687 @cindex disk encryption
11689 The following example specifies a mapping from @file{/dev/sda3} to
11690 @file{/dev/mapper/home} using LUKS---the
11691 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
11692 standard mechanism for disk encryption.
11693 The @file{/dev/mapper/home}
11694 device can then be used as the @code{device} of a @code{file-system}
11695 declaration (@pxref{File Systems}).
11699 (source "/dev/sda3")
11701 (type luks-device-mapping))
11704 Alternatively, to become independent of device numbering, one may obtain
11705 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11709 cryptsetup luksUUID /dev/sda3
11712 and use it as follows:
11716 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11718 (type luks-device-mapping))
11721 @cindex swap encryption
11722 It is also desirable to encrypt swap space, since swap space may contain
11723 sensitive data. One way to accomplish that is to use a swap file in a
11724 file system on a device mapped via LUKS encryption. In this way, the
11725 swap file is encrypted because the entire device is encrypted.
11726 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11728 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11729 may be declared as follows:
11733 (source (list "/dev/sda1" "/dev/sdb1"))
11734 (target "/dev/md0")
11735 (type raid-device-mapping))
11738 The @file{/dev/md0} device can then be used as the @code{device} of a
11739 @code{file-system} declaration (@pxref{File Systems}).
11740 Note that the RAID level need not be given; it is chosen during the
11741 initial creation and formatting of the RAID device and is determined
11742 automatically later.
11745 @node User Accounts
11746 @section User Accounts
11750 @cindex user accounts
11751 User accounts and groups are entirely managed through the
11752 @code{operating-system} declaration. They are specified with the
11753 @code{user-account} and @code{user-group} forms:
11759 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11760 "audio" ;sound card
11761 "video" ;video devices such as webcams
11762 "cdrom")) ;the good ol' CD-ROM
11763 (comment "Bob's sister")
11764 (home-directory "/home/alice"))
11767 When booting or upon completion of @command{guix system reconfigure},
11768 the system ensures that only the user accounts and groups specified in
11769 the @code{operating-system} declaration exist, and with the specified
11770 properties. Thus, account or group creations or modifications made by
11771 directly invoking commands such as @command{useradd} are lost upon
11772 reconfiguration or reboot. This ensures that the system remains exactly
11775 @deftp {Data Type} user-account
11776 Objects of this type represent user accounts. The following members may
11781 The name of the user account.
11785 This is the name (a string) or identifier (a number) of the user group
11786 this account belongs to.
11788 @item @code{supplementary-groups} (default: @code{'()})
11789 Optionally, this can be defined as a list of group names that this
11790 account belongs to.
11792 @item @code{uid} (default: @code{#f})
11793 This is the user ID for this account (a number), or @code{#f}. In the
11794 latter case, a number is automatically chosen by the system when the
11795 account is created.
11797 @item @code{comment} (default: @code{""})
11798 A comment about the account, such as the account owner's full name.
11800 @item @code{home-directory}
11801 This is the name of the home directory for the account.
11803 @item @code{create-home-directory?} (default: @code{#t})
11804 Indicates whether the home directory of this account should be created
11805 if it does not exist yet.
11807 @item @code{shell} (default: Bash)
11808 This is a G-expression denoting the file name of a program to be used as
11809 the shell (@pxref{G-Expressions}).
11811 @item @code{system?} (default: @code{#f})
11812 This Boolean value indicates whether the account is a ``system''
11813 account. System accounts are sometimes treated specially; for instance,
11814 graphical login managers do not list them.
11816 @anchor{user-account-password}
11817 @cindex password, for user accounts
11818 @item @code{password} (default: @code{#f})
11819 You would normally leave this field to @code{#f}, initialize user
11820 passwords as @code{root} with the @command{passwd} command, and then let
11821 users change it with @command{passwd}. Passwords set with
11822 @command{passwd} are of course preserved across reboot and
11825 If you @emph{do} want to set an initial password for an account, then
11826 this field must contain the encrypted password, as a string. You can use the
11827 @code{crypt} procedure for this purpose:
11834 ;; Specify a SHA-512-hashed initial password.
11835 (password (crypt "InitialPassword!" "$6$abc")))
11839 The hash of this initial password will be available in a file in
11840 @file{/gnu/store}, readable by all the users, so this method must be used with
11844 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11845 more information on password encryption, and @ref{Encryption,,, guile, GNU
11846 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11852 User group declarations are even simpler:
11855 (user-group (name "students"))
11858 @deftp {Data Type} user-group
11859 This type is for, well, user groups. There are just a few fields:
11863 The name of the group.
11865 @item @code{id} (default: @code{#f})
11866 The group identifier (a number). If @code{#f}, a new number is
11867 automatically allocated when the group is created.
11869 @item @code{system?} (default: @code{#f})
11870 This Boolean value indicates whether the group is a ``system'' group.
11871 System groups have low numerical IDs.
11873 @item @code{password} (default: @code{#f})
11874 What, user groups can have a password? Well, apparently yes. Unless
11875 @code{#f}, this field specifies the password of the group.
11880 For convenience, a variable lists all the basic user groups one may
11883 @defvr {Scheme Variable} %base-groups
11884 This is the list of basic user groups that users and/or packages expect
11885 to be present on the system. This includes groups such as ``root'',
11886 ``wheel'', and ``users'', as well as groups used to control access to
11887 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11890 @defvr {Scheme Variable} %base-user-accounts
11891 This is the list of basic system accounts that programs may expect to
11892 find on a GNU/Linux system, such as the ``nobody'' account.
11894 Note that the ``root'' account is not included here. It is a
11895 special-case and is automatically added whether or not it is specified.
11898 @node Keyboard Layout
11899 @section Keyboard Layout
11901 @cindex keyboard layout
11903 To specify what each key of your keyboard does, you need to tell the operating
11904 system what @dfn{keyboard layout} you want to use. The default, when nothing
11905 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11906 However, German speakers will usually prefer the German QWERTZ layout, French
11907 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11908 or bépo, and they might even want to further customize the effect of some of
11909 the keys. This section explains how to get that done.
11911 @cindex keyboard layout, definition
11912 There are three components that will want to know about your keyboard layout:
11916 The @emph{bootloader} may want to know what keyboard layout you want to use
11917 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11918 you want, for instance, to make sure that you can type the passphrase of your
11919 encrypted root partition using the right layout.
11922 The @emph{operating system kernel}, Linux, will need that so that the console
11923 is properly configured (@pxref{operating-system Reference,
11924 @code{keyboard-layout}}).
11927 The @emph{graphical display server}, usually Xorg, also has its own idea of
11928 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11931 Guix allows you to configure all three separately but, fortunately, it allows
11932 you to share the same keyboard layout for all three components.
11934 @cindex XKB, keyboard layouts
11935 Keyboard layouts are represented by records created by the
11936 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11937 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11938 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11939 optional variant name, an optional keyboard model name, and a possibly empty
11940 list of additional options. In most cases the layout name is all you care
11941 about. Here are a few example:
11944 ;; The German QWERTZ layout. Here we assume a standard
11945 ;; "pc105" keyboard model.
11946 (keyboard-layout "de")
11948 ;; The bépo variant of the French layout.
11949 (keyboard-layout "fr" "bepo")
11951 ;; The Catalan layout.
11952 (keyboard-layout "es" "cat")
11954 ;; Arabic layout with "Alt-Shift" to switch to US layout.
11955 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
11957 ;; The Latin American Spanish layout. In addition, the
11958 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11959 ;; and the "Menu" key is used as a "Compose" key to enter
11960 ;; accented letters.
11961 (keyboard-layout "latam"
11962 #:options '("ctrl:nocaps" "compose:menu"))
11964 ;; The Russian layout for a ThinkPad keyboard.
11965 (keyboard-layout "ru" #:model "thinkpad")
11967 ;; The "US international" layout, which is the US layout plus
11968 ;; dead keys to enter accented characters. This is for an
11969 ;; Apple MacBook keyboard.
11970 (keyboard-layout "us" "intl" #:model "macbook78")
11973 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11974 for a complete list of supported layouts, variants, and models.
11976 @cindex keyboard layout, configuration
11977 Let's say you want your system to use the Turkish keyboard layout throughout
11978 your system---bootloader, console, and Xorg. Here's what your system
11979 configuration would look like:
11981 @findex set-xorg-configuration
11983 ;; Using the Turkish layout for the bootloader, the console,
11988 (keyboard-layout (keyboard-layout "tr")) ;for the console
11989 (bootloader (bootloader-configuration
11990 (bootloader grub-efi-bootloader)
11991 (target "/boot/efi")
11992 (keyboard-layout keyboard-layout))) ;for GRUB
11993 (services (cons (set-xorg-configuration
11994 (xorg-configuration ;for Xorg
11995 (keyboard-layout keyboard-layout)))
11996 %desktop-services)))
11999 In the example above, for GRUB and for Xorg, we just refer to the
12000 @code{keyboard-layout} field defined above, but we could just as well refer to
12001 a different layout. The @code{set-xorg-configuration} procedure communicates
12002 the desired Xorg configuration to the graphical log-in manager, by default
12005 We've discussed how to specify the @emph{default} keyboard layout of your
12006 system when it starts, but you can also adjust it at run time:
12010 If you're using GNOME, its settings panel has a ``Region & Language'' entry
12011 where you can select one or more keyboard layouts.
12014 Under Xorg, the @command{setxkbmap} command (from the same-named package)
12015 allows you to change the current layout. For example, this is how you would
12016 change the layout to US Dvorak:
12019 setxkbmap us dvorak
12023 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
12024 console. However, note that @code{loadkeys} does @emph{not} use the XKB
12025 keyboard layout categorization described above. The command below loads the
12026 French bépo layout:
12037 A @dfn{locale} defines cultural conventions for a particular language
12038 and region of the world (@pxref{Locales,,, libc, The GNU C Library
12039 Reference Manual}). Each locale has a name that typically has the form
12040 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
12041 @code{fr_LU.utf8} designates the locale for the French language, with
12042 cultural conventions from Luxembourg, and using the UTF-8 encoding.
12044 @cindex locale definition
12045 Usually, you will want to specify the default locale for the machine
12046 using the @code{locale} field of the @code{operating-system} declaration
12047 (@pxref{operating-system Reference, @code{locale}}).
12049 The selected locale is automatically added to the @dfn{locale
12050 definitions} known to the system if needed, with its codeset inferred
12051 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
12052 @code{UTF-8} codeset. Additional locale definitions can be specified in
12053 the @code{locale-definitions} slot of @code{operating-system}---this is
12054 useful, for instance, if the codeset could not be inferred from the
12055 locale name. The default set of locale definitions includes some widely
12056 used locales, but not all the available locales, in order to save space.
12058 For instance, to add the North Frisian locale for Germany, the value of
12062 (cons (locale-definition
12063 (name "fy_DE.utf8") (source "fy_DE"))
12064 %default-locale-definitions)
12067 Likewise, to save space, one might want @code{locale-definitions} to
12068 list only the locales that are actually used, as in:
12071 (list (locale-definition
12072 (name "ja_JP.eucjp") (source "ja_JP")
12073 (charset "EUC-JP")))
12077 The compiled locale definitions are available at
12078 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
12079 version, which is the default location where the GNU@tie{}libc provided
12080 by Guix looks for locale data. This can be overridden using the
12081 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
12082 @code{LOCPATH} and locale packages}).
12084 The @code{locale-definition} form is provided by the @code{(gnu system
12085 locale)} module. Details are given below.
12087 @deftp {Data Type} locale-definition
12088 This is the data type of a locale definition.
12093 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
12094 Reference Manual}, for more information on locale names.
12096 @item @code{source}
12097 The name of the source for that locale. This is typically the
12098 @code{@var{language}_@var{territory}} part of the locale name.
12100 @item @code{charset} (default: @code{"UTF-8"})
12101 The ``character set'' or ``code set'' for that locale,
12102 @uref{https://www.iana.org/assignments/character-sets, as defined by
12108 @defvr {Scheme Variable} %default-locale-definitions
12109 A list of commonly used UTF-8 locales, used as the default
12110 value of the @code{locale-definitions} field of @code{operating-system}
12113 @cindex locale name
12114 @cindex normalized codeset in locale names
12115 These locale definitions use the @dfn{normalized codeset} for the part
12116 that follows the dot in the name (@pxref{Using gettextized software,
12117 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
12118 instance it has @code{uk_UA.utf8} but @emph{not}, say,
12119 @code{uk_UA.UTF-8}.
12122 @subsection Locale Data Compatibility Considerations
12124 @cindex incompatibility, of locale data
12125 @code{operating-system} declarations provide a @code{locale-libcs} field
12126 to specify the GNU@tie{}libc packages that are used to compile locale
12127 declarations (@pxref{operating-system Reference}). ``Why would I
12128 care?'', you may ask. Well, it turns out that the binary format of
12129 locale data is occasionally incompatible from one libc version to
12132 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
12133 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
12134 For instance, a program linked against libc version 2.21 is unable to
12135 read locale data produced with libc 2.22; worse, that program
12136 @emph{aborts} instead of simply ignoring the incompatible locale
12137 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
12138 the incompatible locale data, which is already an improvement.}.
12139 Similarly, a program linked against libc 2.22 can read most, but not
12140 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
12141 data is incompatible); thus calls to @code{setlocale} may fail, but
12142 programs will not abort.
12144 The ``problem'' with Guix is that users have a lot of freedom: They can
12145 choose whether and when to upgrade software in their profiles, and might
12146 be using a libc version different from the one the system administrator
12147 used to build the system-wide locale data.
12149 Fortunately, unprivileged users can also install their own locale data
12150 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
12151 @code{GUIX_LOCPATH} and locale packages}).
12153 Still, it is best if the system-wide locale data at
12154 @file{/run/current-system/locale} is built for all the libc versions
12155 actually in use on the system, so that all the programs can access
12156 it---this is especially crucial on a multi-user system. To do that, the
12157 administrator can specify several libc packages in the
12158 @code{locale-libcs} field of @code{operating-system}:
12161 (use-package-modules base)
12165 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
12168 This example would lead to a system containing locale definitions for
12169 both libc 2.21 and the current version of libc in
12170 @file{/run/current-system/locale}.
12176 @cindex system services
12177 An important part of preparing an @code{operating-system} declaration is
12178 listing @dfn{system services} and their configuration (@pxref{Using the
12179 Configuration System}). System services are typically daemons launched
12180 when the system boots, or other actions needed at that time---e.g.,
12181 configuring network access.
12183 Guix has a broad definition of ``service'' (@pxref{Service
12184 Composition}), but many services are managed by the GNU@tie{}Shepherd
12185 (@pxref{Shepherd Services}). On a running system, the @command{herd}
12186 command allows you to list the available services, show their status,
12187 start and stop them, or do other specific operations (@pxref{Jump
12188 Start,,, shepherd, The GNU Shepherd Manual}). For example:
12194 The above command, run as @code{root}, lists the currently defined
12195 services. The @command{herd doc} command shows a synopsis of the given
12196 service and its associated actions:
12200 Run libc's name service cache daemon (nscd).
12202 # herd doc nscd action invalidate
12203 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
12206 The @command{start}, @command{stop}, and @command{restart} sub-commands
12207 have the effect you would expect. For instance, the commands below stop
12208 the nscd service and restart the Xorg display server:
12212 Service nscd has been stopped.
12213 # herd restart xorg-server
12214 Service xorg-server has been stopped.
12215 Service xorg-server has been started.
12218 The following sections document the available services, starting with
12219 the core services, that may be used in an @code{operating-system}
12223 * Base Services:: Essential system services.
12224 * Scheduled Job Execution:: The mcron service.
12225 * Log Rotation:: The rottlog service.
12226 * Networking Services:: Network setup, SSH daemon, etc.
12227 * X Window:: Graphical display.
12228 * Printing Services:: Local and remote printer support.
12229 * Desktop Services:: D-Bus and desktop services.
12230 * Sound Services:: ALSA and Pulseaudio services.
12231 * Database Services:: SQL databases, key-value stores, etc.
12232 * Mail Services:: IMAP, POP3, SMTP, and all that.
12233 * Messaging Services:: Messaging services.
12234 * Telephony Services:: Telephony services.
12235 * Monitoring Services:: Monitoring services.
12236 * Kerberos Services:: Kerberos services.
12237 * LDAP Services:: LDAP services.
12238 * Web Services:: Web servers.
12239 * Certificate Services:: TLS certificates via Let's Encrypt.
12240 * DNS Services:: DNS daemons.
12241 * VPN Services:: VPN daemons.
12242 * Network File System:: NFS related services.
12243 * Continuous Integration:: The Cuirass service.
12244 * Power Management Services:: Extending battery life.
12245 * Audio Services:: The MPD.
12246 * Virtualization Services:: Virtualization services.
12247 * Version Control Services:: Providing remote access to Git repositories.
12248 * Game Services:: Game servers.
12249 * PAM Mount Service:: Service to mount volumes when logging in.
12250 * Guix Services:: Services relating specifically to Guix.
12251 * Linux Services:: Services tied to the Linux kernel.
12252 * Miscellaneous Services:: Other services.
12255 @node Base Services
12256 @subsection Base Services
12258 The @code{(gnu services base)} module provides definitions for the basic
12259 services that one expects from the system. The services exported by
12260 this module are listed below.
12262 @defvr {Scheme Variable} %base-services
12263 This variable contains a list of basic services (@pxref{Service Types
12264 and Services}, for more information on service objects) one would
12265 expect from the system: a login service (mingetty) on each tty, syslogd,
12266 the libc name service cache daemon (nscd), the udev device manager, and
12269 This is the default value of the @code{services} field of
12270 @code{operating-system} declarations. Usually, when customizing a
12271 system, you will want to append services to @code{%base-services}, like
12275 (append (list (service avahi-service-type)
12276 (service openssh-service-type))
12281 @defvr {Scheme Variable} special-files-service-type
12282 This is the service that sets up ``special files'' such as
12283 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
12285 The value associated with @code{special-files-service-type} services
12286 must be a list of tuples where the first element is the ``special file''
12287 and the second element is its target. By default it is:
12289 @cindex @file{/bin/sh}
12290 @cindex @file{sh}, in @file{/bin}
12292 `(("/bin/sh" ,(file-append bash "/bin/sh")))
12295 @cindex @file{/usr/bin/env}
12296 @cindex @file{env}, in @file{/usr/bin}
12297 If you want to add, say, @code{/usr/bin/env} to your system, you can
12301 `(("/bin/sh" ,(file-append bash "/bin/sh"))
12302 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
12305 Since this is part of @code{%base-services}, you can use
12306 @code{modify-services} to customize the set of special files
12307 (@pxref{Service Reference, @code{modify-services}}). But the simple way
12308 to add a special file is @i{via} the @code{extra-special-file} procedure
12312 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
12313 Use @var{target} as the ``special file'' @var{file}.
12315 For example, adding the following lines to the @code{services} field of
12316 your operating system declaration leads to a @file{/usr/bin/env}
12320 (extra-special-file "/usr/bin/env"
12321 (file-append coreutils "/bin/env"))
12325 @deffn {Scheme Procedure} host-name-service @var{name}
12326 Return a service that sets the host name to @var{name}.
12329 @defvr {Scheme Variable} console-font-service-type
12330 Install the given fonts on the specified ttys (fonts are per
12331 virtual console on the kernel Linux). The value of this service is a list of
12332 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
12333 package or any valid argument to @command{setfont}, as in this example:
12336 `(("tty1" . "LatGrkCyr-8x16")
12337 ("tty2" . ,(file-append
12339 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
12340 ("tty3" . ,(file-append
12342 "/share/consolefonts/ter-132n"))) ; for HDPI
12346 @deffn {Scheme Procedure} login-service @var{config}
12347 Return a service to run login according to @var{config}, a
12348 @code{<login-configuration>} object, which specifies the message of the day,
12349 among other things.
12352 @deftp {Data Type} login-configuration
12353 This is the data type representing the configuration of login.
12358 @cindex message of the day
12359 A file-like object containing the ``message of the day''.
12361 @item @code{allow-empty-passwords?} (default: @code{#t})
12362 Allow empty passwords by default so that first-time users can log in when
12363 the 'root' account has just been created.
12368 @deffn {Scheme Procedure} mingetty-service @var{config}
12369 Return a service to run mingetty according to @var{config}, a
12370 @code{<mingetty-configuration>} object, which specifies the tty to run, among
12374 @deftp {Data Type} mingetty-configuration
12375 This is the data type representing the configuration of Mingetty, which
12376 provides the default implementation of virtual console log-in.
12381 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
12383 @item @code{auto-login} (default: @code{#f})
12384 When true, this field must be a string denoting the user name under
12385 which the system automatically logs in. When it is @code{#f}, a
12386 user name and password must be entered to log in.
12388 @item @code{login-program} (default: @code{#f})
12389 This must be either @code{#f}, in which case the default log-in program
12390 is used (@command{login} from the Shadow tool suite), or a gexp denoting
12391 the name of the log-in program.
12393 @item @code{login-pause?} (default: @code{#f})
12394 When set to @code{#t} in conjunction with @var{auto-login}, the user
12395 will have to press a key before the log-in shell is launched.
12397 @item @code{mingetty} (default: @var{mingetty})
12398 The Mingetty package to use.
12403 @deffn {Scheme Procedure} agetty-service @var{config}
12404 Return a service to run agetty according to @var{config}, an
12405 @code{<agetty-configuration>} object, which specifies the tty to run,
12406 among other things.
12409 @deftp {Data Type} agetty-configuration
12410 This is the data type representing the configuration of agetty, which
12411 implements virtual and serial console log-in. See the @code{agetty(8)}
12412 man page for more information.
12417 The name of the console this agetty runs on, as a string---e.g.,
12418 @code{"ttyS0"}. This argument is optional, it will default to
12419 a reasonable default serial port used by the kernel Linux.
12421 For this, if there is a value for an option @code{agetty.tty} in the kernel
12422 command line, agetty will extract the device name of the serial port
12423 from it and use that.
12425 If not and if there is a value for an option @code{console} with a tty in
12426 the Linux command line, agetty will extract the device name of the
12427 serial port from it and use that.
12429 In both cases, agetty will leave the other serial device settings
12430 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
12433 @item @code{baud-rate} (default: @code{#f})
12434 A string containing a comma-separated list of one or more baud rates, in
12437 @item @code{term} (default: @code{#f})
12438 A string containing the value used for the @code{TERM} environment
12441 @item @code{eight-bits?} (default: @code{#f})
12442 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
12445 @item @code{auto-login} (default: @code{#f})
12446 When passed a login name, as a string, the specified user will be logged
12447 in automatically without prompting for their login name or password.
12449 @item @code{no-reset?} (default: @code{#f})
12450 When @code{#t}, don't reset terminal cflags (control modes).
12452 @item @code{host} (default: @code{#f})
12453 This accepts a string containing the "login_host", which will be written
12454 into the @file{/var/run/utmpx} file.
12456 @item @code{remote?} (default: @code{#f})
12457 When set to @code{#t} in conjunction with @var{host}, this will add an
12458 @code{-r} fakehost option to the command line of the login program
12459 specified in @var{login-program}.
12461 @item @code{flow-control?} (default: @code{#f})
12462 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
12464 @item @code{no-issue?} (default: @code{#f})
12465 When set to @code{#t}, the contents of the @file{/etc/issue} file will
12466 not be displayed before presenting the login prompt.
12468 @item @code{init-string} (default: @code{#f})
12469 This accepts a string that will be sent to the tty or modem before
12470 sending anything else. It can be used to initialize a modem.
12472 @item @code{no-clear?} (default: @code{#f})
12473 When set to @code{#t}, agetty will not clear the screen before showing
12476 @item @code{login-program} (default: (file-append shadow "/bin/login"))
12477 This must be either a gexp denoting the name of a log-in program, or
12478 unset, in which case the default value is the @command{login} from the
12481 @item @code{local-line} (default: @code{#f})
12482 Control the CLOCAL line flag. This accepts one of three symbols as
12483 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
12484 the default value chosen by agetty is @code{'auto}.
12486 @item @code{extract-baud?} (default: @code{#f})
12487 When set to @code{#t}, instruct agetty to try to extract the baud rate
12488 from the status messages produced by certain types of modems.
12490 @item @code{skip-login?} (default: @code{#f})
12491 When set to @code{#t}, do not prompt the user for a login name. This
12492 can be used with @var{login-program} field to use non-standard login
12495 @item @code{no-newline?} (default: @code{#f})
12496 When set to @code{#t}, do not print a newline before printing the
12497 @file{/etc/issue} file.
12499 @c Is this dangerous only when used with login-program, or always?
12500 @item @code{login-options} (default: @code{#f})
12501 This option accepts a string containing options that are passed to the
12502 login program. When used with the @var{login-program}, be aware that a
12503 malicious user could try to enter a login name containing embedded
12504 options that could be parsed by the login program.
12506 @item @code{login-pause} (default: @code{#f})
12507 When set to @code{#t}, wait for any key before showing the login prompt.
12508 This can be used in conjunction with @var{auto-login} to save memory by
12509 lazily spawning shells.
12511 @item @code{chroot} (default: @code{#f})
12512 Change root to the specified directory. This option accepts a directory
12515 @item @code{hangup?} (default: @code{#f})
12516 Use the Linux system call @code{vhangup} to do a virtual hangup of the
12517 specified terminal.
12519 @item @code{keep-baud?} (default: @code{#f})
12520 When set to @code{#t}, try to keep the existing baud rate. The baud
12521 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
12524 @item @code{timeout} (default: @code{#f})
12525 When set to an integer value, terminate if no user name could be read
12526 within @var{timeout} seconds.
12528 @item @code{detect-case?} (default: @code{#f})
12529 When set to @code{#t}, turn on support for detecting an uppercase-only
12530 terminal. This setting will detect a login name containing only
12531 uppercase letters as indicating an uppercase-only terminal and turn on
12532 some upper-to-lower case conversions. Note that this will not support
12533 Unicode characters.
12535 @item @code{wait-cr?} (default: @code{#f})
12536 When set to @code{#t}, wait for the user or modem to send a
12537 carriage-return or linefeed character before displaying
12538 @file{/etc/issue} or login prompt. This is typically used with the
12539 @var{init-string} option.
12541 @item @code{no-hints?} (default: @code{#f})
12542 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
12545 @item @code{no-hostname?} (default: @code{#f})
12546 By default, the hostname is printed. When this option is set to
12547 @code{#t}, no hostname will be shown at all.
12549 @item @code{long-hostname?} (default: @code{#f})
12550 By default, the hostname is only printed until the first dot. When this
12551 option is set to @code{#t}, the fully qualified hostname by
12552 @code{gethostname} or @code{getaddrinfo} is shown.
12554 @item @code{erase-characters} (default: @code{#f})
12555 This option accepts a string of additional characters that should be
12556 interpreted as backspace when the user types their login name.
12558 @item @code{kill-characters} (default: @code{#f})
12559 This option accepts a string that should be interpreted to mean "ignore
12560 all previous characters" (also called a "kill" character) when the user
12561 types their login name.
12563 @item @code{chdir} (default: @code{#f})
12564 This option accepts, as a string, a directory path that will be changed
12567 @item @code{delay} (default: @code{#f})
12568 This options accepts, as an integer, the number of seconds to sleep
12569 before opening the tty and displaying the login prompt.
12571 @item @code{nice} (default: @code{#f})
12572 This option accepts, as an integer, the nice value with which to run the
12573 @command{login} program.
12575 @item @code{extra-options} (default: @code{'()})
12576 This option provides an "escape hatch" for the user to provide arbitrary
12577 command-line arguments to @command{agetty} as a list of strings.
12582 @deffn {Scheme Procedure} kmscon-service-type @var{config}
12583 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
12584 according to @var{config}, a @code{<kmscon-configuration>} object, which
12585 specifies the tty to run, among other things.
12588 @deftp {Data Type} kmscon-configuration
12589 This is the data type representing the configuration of Kmscon, which
12590 implements virtual console log-in.
12594 @item @code{virtual-terminal}
12595 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
12597 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
12598 A gexp denoting the name of the log-in program. The default log-in program is
12599 @command{login} from the Shadow tool suite.
12601 @item @code{login-arguments} (default: @code{'("-p")})
12602 A list of arguments to pass to @command{login}.
12604 @item @code{auto-login} (default: @code{#f})
12605 When passed a login name, as a string, the specified user will be logged
12606 in automatically without prompting for their login name or password.
12608 @item @code{hardware-acceleration?} (default: #f)
12609 Whether to use hardware acceleration.
12611 @item @code{kmscon} (default: @var{kmscon})
12612 The Kmscon package to use.
12617 @cindex name service cache daemon
12619 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
12620 [#:name-services '()]
12621 Return a service that runs the libc name service cache daemon (nscd) with the
12622 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
12623 Service Switch}, for an example.
12625 For convenience, the Shepherd service for nscd provides the following actions:
12629 @cindex cache invalidation, nscd
12630 @cindex nscd, cache invalidation
12631 This invalidate the given cache. For instance, running:
12634 herd invalidate nscd hosts
12638 invalidates the host name lookup cache of nscd.
12641 Running @command{herd statistics nscd} displays information about nscd usage
12647 @defvr {Scheme Variable} %nscd-default-configuration
12648 This is the default @code{<nscd-configuration>} value (see below) used
12649 by @code{nscd-service}. It uses the caches defined by
12650 @code{%nscd-default-caches}; see below.
12653 @deftp {Data Type} nscd-configuration
12654 This is the data type representing the name service cache daemon (nscd)
12659 @item @code{name-services} (default: @code{'()})
12660 List of packages denoting @dfn{name services} that must be visible to
12661 the nscd---e.g., @code{(list @var{nss-mdns})}.
12663 @item @code{glibc} (default: @var{glibc})
12664 Package object denoting the GNU C Library providing the @command{nscd}
12667 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
12668 Name of the nscd log file. This is where debugging output goes when
12669 @code{debug-level} is strictly positive.
12671 @item @code{debug-level} (default: @code{0})
12672 Integer denoting the debugging levels. Higher numbers mean that more
12673 debugging output is logged.
12675 @item @code{caches} (default: @code{%nscd-default-caches})
12676 List of @code{<nscd-cache>} objects denoting things to be cached; see
12682 @deftp {Data Type} nscd-cache
12683 Data type representing a cache database of nscd and its parameters.
12687 @item @code{database}
12688 This is a symbol representing the name of the database to be cached.
12689 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
12690 @code{services}, which designate the corresponding NSS database
12691 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
12693 @item @code{positive-time-to-live}
12694 @itemx @code{negative-time-to-live} (default: @code{20})
12695 A number representing the number of seconds during which a positive or
12696 negative lookup result remains in cache.
12698 @item @code{check-files?} (default: @code{#t})
12699 Whether to check for updates of the files corresponding to
12702 For instance, when @var{database} is @code{hosts}, setting this flag
12703 instructs nscd to check for updates in @file{/etc/hosts} and to take
12706 @item @code{persistent?} (default: @code{#t})
12707 Whether the cache should be stored persistently on disk.
12709 @item @code{shared?} (default: @code{#t})
12710 Whether the cache should be shared among users.
12712 @item @code{max-database-size} (default: 32@tie{}MiB)
12713 Maximum size in bytes of the database cache.
12715 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
12716 @c settings, so leave them out.
12721 @defvr {Scheme Variable} %nscd-default-caches
12722 List of @code{<nscd-cache>} objects used by default by
12723 @code{nscd-configuration} (see above).
12725 It enables persistent and aggressive caching of service and host name
12726 lookups. The latter provides better host name lookup performance,
12727 resilience in the face of unreliable name servers, and also better
12728 privacy---often the result of host name lookups is in local cache, so
12729 external name servers do not even need to be queried.
12732 @anchor{syslog-configuration-type}
12735 @deftp {Data Type} syslog-configuration
12736 This data type represents the configuration of the syslog daemon.
12739 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12740 The syslog daemon to use.
12742 @item @code{config-file} (default: @code{%default-syslog.conf})
12743 The syslog configuration file to use.
12748 @anchor{syslog-service}
12750 @deffn {Scheme Procedure} syslog-service @var{config}
12751 Return a service that runs a syslog daemon according to @var{config}.
12753 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12754 information on the configuration file syntax.
12757 @defvr {Scheme Variable} guix-service-type
12758 This is the type of the service that runs the build daemon,
12759 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12760 @code{guix-configuration} record as described below.
12763 @anchor{guix-configuration-type}
12764 @deftp {Data Type} guix-configuration
12765 This data type represents the configuration of the Guix build daemon.
12766 @xref{Invoking guix-daemon}, for more information.
12769 @item @code{guix} (default: @var{guix})
12770 The Guix package to use.
12772 @item @code{build-group} (default: @code{"guixbuild"})
12773 Name of the group for build user accounts.
12775 @item @code{build-accounts} (default: @code{10})
12776 Number of build user accounts to create.
12778 @item @code{authorize-key?} (default: @code{#t})
12779 @cindex substitutes, authorization thereof
12780 Whether to authorize the substitute keys listed in
12781 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12782 (@pxref{Substitutes}).
12784 @vindex %default-authorized-guix-keys
12785 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12786 The list of authorized key files for archive imports, as a list of
12787 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12788 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12790 @item @code{use-substitutes?} (default: @code{#t})
12791 Whether to use substitutes.
12793 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12794 The list of URLs where to look for substitutes by default.
12796 @item @code{max-silent-time} (default: @code{0})
12797 @itemx @code{timeout} (default: @code{0})
12798 The number of seconds of silence and the number of seconds of activity,
12799 respectively, after which a build process times out. A value of zero
12800 disables the timeout.
12802 @item @code{log-compression} (default: @code{'bzip2})
12803 The type of compression used for build logs---one of @code{gzip},
12804 @code{bzip2}, or @code{none}.
12806 @item @code{extra-options} (default: @code{'()})
12807 List of extra command-line options for @command{guix-daemon}.
12809 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12810 File where @command{guix-daemon}'s standard output and standard error
12813 @cindex HTTP proxy, for @code{guix-daemon}
12814 @cindex proxy, for @code{guix-daemon} HTTP access
12815 @item @code{http-proxy} (default: @code{#f})
12816 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
12817 derivations and substitutes.
12819 It is also possible to change the daemon's proxy at run time through the
12820 @code{set-http-proxy} action, which restarts it:
12823 herd set-http-proxy guix-daemon http://localhost:8118
12826 To clear the proxy settings, run:
12829 herd set-http-proxy guix-daemon
12832 @item @code{tmpdir} (default: @code{#f})
12833 A directory path where the @command{guix-daemon} will perform builds.
12838 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12839 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12840 udev rules can be provided as a list of files through the @var{rules}
12841 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12842 @code{(gnu services base)} simplify the creation of such rule files.
12845 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12846 Return a udev-rule file named @var{file-name} containing the rules
12847 defined by the @var{contents} literal.
12849 In the following example, a rule for a USB device is defined to be
12850 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12851 upon detecting a USB device with a given product identifier.
12854 (define %example-udev-rule
12856 "90-usb-thing.rules"
12857 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12858 "ATTR@{product@}==\"Example\", "
12859 "RUN+=\"/path/to/script\"")))
12862 The @command{herd rules udev} command, as root, returns the name of the
12863 directory containing all the active udev rules.
12866 Here we show how the default @var{udev-service} can be extended with it.
12872 (modify-services %desktop-services
12873 (udev-service-type config =>
12874 (udev-configuration (inherit config)
12875 (rules (append (udev-configuration-rules config)
12876 (list %example-udev-rule))))))))
12879 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12880 Return a udev file named @var{file-name} containing the rules defined
12881 within @var{file}, a file-like object.
12883 The following example showcases how we can use an existing rule file.
12886 (use-modules (guix download) ;for url-fetch
12887 (guix packages) ;for origin
12890 (define %android-udev-rules
12892 "51-android-udev.rules"
12893 (let ((version "20170910"))
12896 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12897 "android-udev-rules/" version "/51-android.rules"))
12899 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12903 Additionally, Guix package definitions can be included in @var{rules} in
12904 order to extend the udev rules with the definitions found under their
12905 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12906 @var{file->udev-rule} example, we could have used the
12907 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12908 packages android)} module.
12910 The following example shows how to use the @var{android-udev-rules}
12911 package so that the Android tool @command{adb} can detect devices
12912 without root privileges. It also details how to create the
12913 @code{adbusers} group, which is required for the proper functioning of
12914 the rules defined within the @var{android-udev-rules} package. To
12915 create such a group, we must define it both as part of the
12916 @var{supplementary-groups} of our @var{user-account} declaration, as
12917 well as in the @var{groups} field of the @var{operating-system} record.
12920 (use-modules (gnu packages android) ;for android-udev-rules
12921 (gnu system shadow) ;for user-group
12926 (users (cons (user-account
12928 (supplementary-groups
12929 '("adbusers" ;for adb
12930 "wheel" "netdev" "audio" "video")))))
12932 (groups (cons (user-group (system? #t) (name "adbusers"))
12938 (modify-services %desktop-services
12941 (udev-configuration (inherit config)
12942 (rules (cons android-udev-rules
12943 (udev-configuration-rules config))))))))
12946 @defvr {Scheme Variable} urandom-seed-service-type
12947 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
12948 when rebooting. It also tries to seed @file{/dev/urandom} from
12949 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12953 @defvr {Scheme Variable} %random-seed-file
12954 This is the name of the file where some random bytes are saved by
12955 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12956 It defaults to @file{/var/lib/random-seed}.
12961 @defvr {Scheme Variable} gpm-service-type
12962 This is the type of the service that runs GPM, the @dfn{general-purpose
12963 mouse daemon}, which provides mouse support to the Linux console. GPM
12964 allows users to use the mouse in the console, notably to select, copy,
12967 The value for services of this type must be a @code{gpm-configuration}
12968 (see below). This service is not part of @code{%base-services}.
12971 @deftp {Data Type} gpm-configuration
12972 Data type representing the configuration of GPM.
12975 @item @code{options} (default: @code{%default-gpm-options})
12976 Command-line options passed to @command{gpm}. The default set of
12977 options instruct @command{gpm} to listen to mouse events on
12978 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12981 @item @code{gpm} (default: @code{gpm})
12982 The GPM package to use.
12987 @anchor{guix-publish-service-type}
12988 @deffn {Scheme Variable} guix-publish-service-type
12989 This is the service type for @command{guix publish} (@pxref{Invoking
12990 guix publish}). Its value must be a @code{guix-publish-configuration}
12991 object, as described below.
12993 This assumes that @file{/etc/guix} already contains a signing key pair as
12994 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12995 archive}). If that is not the case, the service will fail to start.
12998 @deftp {Data Type} guix-publish-configuration
12999 Data type representing the configuration of the @code{guix publish}
13003 @item @code{guix} (default: @code{guix})
13004 The Guix package to use.
13006 @item @code{port} (default: @code{80})
13007 The TCP port to listen for connections.
13009 @item @code{host} (default: @code{"localhost"})
13010 The host (and thus, network interface) to listen to. Use
13011 @code{"0.0.0.0"} to listen on all the network interfaces.
13013 @item @code{compression} (default: @code{'(("gzip" 3))})
13014 This is a list of compression method/level tuple used when compressing
13015 substitutes. For example, to compress all substitutes with @emph{both} lzip
13016 at level 7 and gzip at level 9, write:
13019 '(("lzip" 7) ("gzip" 9))
13022 Level 9 achieves the best compression ratio at the expense of increased CPU
13023 usage, whereas level 1 achieves fast compression.
13025 An empty list disables compression altogether.
13027 @item @code{nar-path} (default: @code{"nar"})
13028 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
13029 publish, @code{--nar-path}}, for details.
13031 @item @code{cache} (default: @code{#f})
13032 When it is @code{#f}, disable caching and instead generate archives on
13033 demand. Otherwise, this should be the name of a directory---e.g.,
13034 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
13035 archives and meta-data ready to be sent. @xref{Invoking guix publish,
13036 @option{--cache}}, for more information on the tradeoffs involved.
13038 @item @code{workers} (default: @code{#f})
13039 When it is an integer, this is the number of worker threads used for
13040 caching; when @code{#f}, the number of processors is used.
13041 @xref{Invoking guix publish, @option{--workers}}, for more information.
13043 @item @code{ttl} (default: @code{#f})
13044 When it is an integer, this denotes the @dfn{time-to-live} in seconds
13045 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
13046 for more information.
13050 @anchor{rngd-service}
13051 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
13052 [#:device "/dev/hwrng"]
13053 Return a service that runs the @command{rngd} program from @var{rng-tools}
13054 to add @var{device} to the kernel's entropy pool. The service will fail if
13055 @var{device} does not exist.
13058 @anchor{pam-limits-service}
13059 @cindex session limits
13064 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
13066 Return a service that installs a configuration file for the
13067 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
13068 @code{pam_limits} module}. The procedure optionally takes a list of
13069 @code{pam-limits-entry} values, which can be used to specify
13070 @code{ulimit} limits and nice priority limits to user sessions.
13072 The following limits definition sets two hard and soft limits for all
13073 login sessions of users in the @code{realtime} group:
13076 (pam-limits-service
13078 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
13079 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
13082 The first entry increases the maximum realtime priority for
13083 non-privileged processes; the second entry lifts any restriction of the
13084 maximum address space that can be locked in memory. These settings are
13085 commonly used for real-time audio systems.
13088 @node Scheduled Job Execution
13089 @subsection Scheduled Job Execution
13093 @cindex scheduling jobs
13094 The @code{(gnu services mcron)} module provides an interface to
13095 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
13096 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
13097 Unix @command{cron} daemon; the main difference is that it is
13098 implemented in Guile Scheme, which provides a lot of flexibility when
13099 specifying the scheduling of jobs and their actions.
13101 The example below defines an operating system that runs the
13102 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
13103 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
13104 well as the @command{mkid} command on behalf of an unprivileged user
13105 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
13106 gexps to introduce job definitions that are passed to mcron
13107 (@pxref{G-Expressions}).
13110 (use-modules (guix) (gnu) (gnu services mcron))
13111 (use-package-modules base idutils)
13113 (define updatedb-job
13114 ;; Run 'updatedb' at 3AM every day. Here we write the
13115 ;; job's action as a Scheme procedure.
13116 #~(job '(next-hour '(3))
13118 (execl (string-append #$findutils "/bin/updatedb")
13120 "--prunepaths=/tmp /var/tmp /gnu/store"))))
13122 (define garbage-collector-job
13123 ;; Collect garbage 5 minutes after midnight every day.
13124 ;; The job's action is a shell command.
13125 #~(job "5 0 * * *" ;Vixie cron syntax
13128 (define idutils-job
13129 ;; Update the index database as user "charlie" at 12:15PM
13130 ;; and 19:15PM. This runs from the user's home directory.
13131 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
13132 (string-append #$idutils "/bin/mkid src")
13137 (services (cons (service mcron-service-type
13138 (mcron-configuration
13139 (jobs (list garbage-collector-job
13145 For more complex jobs defined in Scheme where you need control over the top
13146 level, for instance to introduce a @code{use-modules} form, you can move your
13147 code to a separate program using the @code{program-file} procedure of the
13148 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
13152 (define %battery-alert-job
13153 ;; Beep when the battery percentage falls below %MIN-LEVEL.
13155 '(next-minute (range 0 60 1))
13157 "battery-alert.scm"
13158 (with-imported-modules (source-module-closure
13159 '((guix build utils)))
13161 (define %min-level 20)
13162 (use-modules (guix build utils)
13165 (ice-9 textual-ports)
13167 (setenv "LC_ALL" "C") ;ensure English output
13168 (and-let* ((input-pipe (open-pipe*
13170 #$(file-append acpi "/bin/acpi")))
13171 (output (get-string-all input-pipe))
13172 (m (string-match "Discharging, ([0-9]+)%" output))
13173 (level (string->number (match:substring m 1)))
13174 ((< level %min-level)))
13175 (format #t "warning: Battery level is low (~a%)~%" level)
13176 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
13179 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
13180 for more information on mcron job specifications. Below is the
13181 reference of the mcron service.
13183 On a running system, you can use the @code{schedule} action of the service to
13184 visualize the mcron jobs that will be executed next:
13187 # herd schedule mcron
13191 The example above lists the next five tasks that will be executed, but you can
13192 also specify the number of tasks to display:
13195 # herd schedule mcron 10
13198 @defvr {Scheme Variable} mcron-service-type
13199 This is the type of the @code{mcron} service, whose value is an
13200 @code{mcron-configuration} object.
13202 This service type can be the target of a service extension that provides
13203 it additional job specifications (@pxref{Service Composition}). In
13204 other words, it is possible to define services that provide additional
13208 @deftp {Data Type} mcron-configuration
13209 Data type representing the configuration of mcron.
13212 @item @code{mcron} (default: @var{mcron})
13213 The mcron package to use.
13216 This is a list of gexps (@pxref{G-Expressions}), where each gexp
13217 corresponds to an mcron job specification (@pxref{Syntax, mcron job
13218 specifications,, mcron, GNU@tie{}mcron}).
13224 @subsection Log Rotation
13227 @cindex log rotation
13229 Log files such as those found in @file{/var/log} tend to grow endlessly,
13230 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
13231 their contents in separate files, possibly compressed. The @code{(gnu
13232 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
13233 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
13235 This service is part of @code{%base-services}, and thus enabled by
13236 default, with the default settings, for commonly encountered log files.
13237 The example below shows how to extend it with an additional
13238 @dfn{rotation}, should you need to do that (usually, services that
13239 produce log files already take care of that):
13242 (use-modules (guix) (gnu))
13243 (use-service-modules admin)
13245 (define my-log-files
13246 ;; Log files that I want to rotate.
13247 '("/var/log/something.log" "/var/log/another.log"))
13251 (services (cons (simple-service 'rotate-my-stuff
13252 rottlog-service-type
13253 (list (log-rotation
13255 (files my-log-files))))
13259 @defvr {Scheme Variable} rottlog-service-type
13260 This is the type of the Rottlog service, whose value is a
13261 @code{rottlog-configuration} object.
13263 Other services can extend this one with new @code{log-rotation} objects
13264 (see below), thereby augmenting the set of files to be rotated.
13266 This service type can define mcron jobs (@pxref{Scheduled Job
13267 Execution}) to run the rottlog service.
13270 @deftp {Data Type} rottlog-configuration
13271 Data type representing the configuration of rottlog.
13274 @item @code{rottlog} (default: @code{rottlog})
13275 The Rottlog package to use.
13277 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
13278 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
13279 rottlog, GNU Rot[t]log Manual}).
13281 @item @code{rotations} (default: @code{%default-rotations})
13282 A list of @code{log-rotation} objects as defined below.
13285 This is a list of gexps where each gexp corresponds to an mcron job
13286 specification (@pxref{Scheduled Job Execution}).
13290 @deftp {Data Type} log-rotation
13291 Data type representing the rotation of a group of log files.
13293 Taking an example from the Rottlog manual (@pxref{Period Related File
13294 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
13300 (files '("/var/log/apache/*"))
13301 (options '("storedir apache-archives"
13307 The list of fields is as follows:
13310 @item @code{frequency} (default: @code{'weekly})
13311 The log rotation frequency, a symbol.
13314 The list of files or file glob patterns to rotate.
13316 @item @code{options} (default: @code{'()})
13317 The list of rottlog options for this rotation (@pxref{Configuration
13318 parameters,,, rottlog, GNU Rot[t]lg Manual}).
13320 @item @code{post-rotate} (default: @code{#f})
13321 Either @code{#f} or a gexp to execute once the rotation has completed.
13325 @defvr {Scheme Variable} %default-rotations
13326 Specifies weekly rotation of @code{%rotated-files} and of
13327 @file{/var/log/guix-daemon.log}.
13330 @defvr {Scheme Variable} %rotated-files
13331 The list of syslog-controlled files to be rotated. By default it is:
13332 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
13333 "/var/log/maillog")}.
13336 @node Networking Services
13337 @subsection Networking Services
13339 The @code{(gnu services networking)} module provides services to configure
13340 the network interface.
13342 @cindex DHCP, networking service
13343 @defvr {Scheme Variable} dhcp-client-service-type
13344 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
13345 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
13346 is the DHCP client package to use, @code{isc-dhcp} by default.
13349 @deffn {Scheme Procedure} dhcpd-service-type
13350 This type defines a service that runs a DHCP daemon. To create a
13351 service of this type, you must supply a @code{<dhcpd-configuration>}.
13355 (service dhcpd-service-type
13356 (dhcpd-configuration
13357 (config-file (local-file "my-dhcpd.conf"))
13358 (interfaces '("enp0s25"))))
13362 @deftp {Data Type} dhcpd-configuration
13364 @item @code{package} (default: @code{isc-dhcp})
13365 The package that provides the DHCP daemon. This package is expected to
13366 provide the daemon at @file{sbin/dhcpd} relative to its output
13367 directory. The default package is the
13368 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
13369 @item @code{config-file} (default: @code{#f})
13370 The configuration file to use. This is required. It will be passed to
13371 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
13372 object (@pxref{G-Expressions, file-like objects}). See @code{man
13373 dhcpd.conf} for details on the configuration file syntax.
13374 @item @code{version} (default: @code{"4"})
13375 The DHCP version to use. The ISC DHCP server supports the values ``4'',
13376 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
13377 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
13379 @item @code{run-directory} (default: @code{"/run/dhcpd"})
13380 The run directory to use. At service activation time, this directory
13381 will be created if it does not exist.
13382 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
13383 The PID file to use. This corresponds to the @code{-pf} option of
13384 @code{dhcpd}. See @code{man dhcpd} for details.
13385 @item @code{interfaces} (default: @code{'()})
13386 The names of the network interfaces on which dhcpd should listen for
13387 broadcasts. If this list is not empty, then its elements (which must be
13388 strings) will be appended to the @code{dhcpd} invocation when starting
13389 the daemon. It may not be necessary to explicitly specify any
13390 interfaces here; see @code{man dhcpd} for details.
13394 @defvr {Scheme Variable} static-networking-service-type
13395 This is the type for statically-configured network interfaces.
13396 @c TODO Document <static-networking> data structures.
13399 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
13400 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
13401 [#:requirement @code{'(udev)}]
13402 Return a service that starts @var{interface} with address @var{ip}. If
13403 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
13404 it must be a string specifying the default network gateway. @var{requirement}
13405 can be used to declare a dependency on another service before configuring the
13408 This procedure can be called several times, one for each network
13409 interface of interest. Behind the scenes what it does is extend
13410 @code{static-networking-service-type} with additional network interfaces
13416 (static-networking-service "eno1" "192.168.1.82"
13417 #:gateway "192.168.1.2"
13418 #:name-servers '("192.168.1.2"))
13425 @cindex network management
13426 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
13427 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
13428 management daemon that aims to simplify wired and wireless networking.
13430 This service adds the @var{wicd} package to the global profile, providing
13431 several commands to interact with the daemon and configure networking:
13432 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
13433 and @command{wicd-curses} user interfaces.
13436 @cindex ModemManager
13438 @defvr {Scheme Variable} modem-manager-service-type
13439 This is the service type for the
13440 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
13441 service. The value for this service type is a
13442 @code{modem-manager-configuration} record.
13444 This service is part of @code{%desktop-services} (@pxref{Desktop
13448 @deftp {Data Type} modem-manager-configuration
13449 Data type representing the configuration of ModemManager.
13452 @item @code{modem-manager} (default: @code{modem-manager})
13453 The ModemManager package to use.
13458 @cindex USB_ModeSwitch
13459 @cindex Modeswitching
13461 @defvr {Scheme Variable} usb-modeswitch-service-type
13462 This is the service type for the
13463 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
13464 value for this service type is a @code{usb-modeswitch-configuration} record.
13466 When plugged in, some USB modems (and other USB devices) initially present
13467 themselves as a read-only storage medium and not as a modem. They need to be
13468 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
13469 installs udev rules to automatically modeswitch these devices when they are
13472 This service is part of @code{%desktop-services} (@pxref{Desktop
13476 @deftp {Data Type} usb-modeswitch-configuration
13477 Data type representing the configuration of USB_ModeSwitch.
13480 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
13481 The USB_ModeSwitch package providing the binaries for modeswitching.
13483 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
13484 The package providing the device data and udev rules file used by
13487 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
13488 Which config file to use for the USB_ModeSwitch dispatcher. By default the
13489 config file shipped with USB_ModeSwitch is used which disables logging to
13490 @file{/var/log} among other default settings. If set to @code{#f}, no config
13496 @cindex NetworkManager
13498 @defvr {Scheme Variable} network-manager-service-type
13499 This is the service type for the
13500 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
13501 service. The value for this service type is a
13502 @code{network-manager-configuration} record.
13504 This service is part of @code{%desktop-services} (@pxref{Desktop
13508 @deftp {Data Type} network-manager-configuration
13509 Data type representing the configuration of NetworkManager.
13512 @item @code{network-manager} (default: @code{network-manager})
13513 The NetworkManager package to use.
13515 @item @code{dns} (default: @code{"default"})
13516 Processing mode for DNS, which affects how NetworkManager uses the
13517 @code{resolv.conf} configuration file.
13521 NetworkManager will update @code{resolv.conf} to reflect the nameservers
13522 provided by currently active connections.
13525 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
13526 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
13527 then update @code{resolv.conf} to point to the local nameserver.
13529 With this setting, you can share your network connection. For example when
13530 you want to share your network connection to another laptop @i{via} an
13531 Ethernet cable, you can open @command{nm-connection-editor} and configure the
13532 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
13533 and reestablish the connection (or reboot).
13535 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
13536 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
13537 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
13538 browser on your host system, or connect to the VM @i{via} SSH
13539 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
13540 host-to-guest connection, run this command once:
13543 nmcli connection add type tun \
13544 connection.interface-name tap0 \
13545 tun.mode tap tun.owner $(id -u) \
13546 ipv4.method shared \
13547 ipv4.addresses 172.28.112.1/24
13550 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
13551 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
13552 @command{qemu-system-...}.
13555 NetworkManager will not modify @code{resolv.conf}.
13558 @item @code{vpn-plugins} (default: @code{'()})
13559 This is the list of available plugins for virtual private networks
13560 (VPNs). An example of this is the @code{network-manager-openvpn}
13561 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
13567 @deffn {Scheme Variable} connman-service-type
13568 This is the service type to run @url{https://01.org/connman,Connman},
13569 a network connection manager.
13571 Its value must be an
13572 @code{connman-configuration} record as in this example:
13575 (service connman-service-type
13576 (connman-configuration
13577 (disable-vpn? #t)))
13580 See below for details about @code{connman-configuration}.
13583 @deftp {Data Type} connman-configuration
13584 Data Type representing the configuration of connman.
13587 @item @code{connman} (default: @var{connman})
13588 The connman package to use.
13590 @item @code{disable-vpn?} (default: @code{#f})
13591 When true, disable connman's vpn plugin.
13595 @cindex WPA Supplicant
13596 @defvr {Scheme Variable} wpa-supplicant-service-type
13597 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
13598 supplicant}, an authentication daemon required to authenticate against
13599 encrypted WiFi or ethernet networks.
13602 @deftp {Data Type} wpa-supplicant-configuration
13603 Data type representing the configuration of WPA Supplicant.
13605 It takes the following parameters:
13608 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
13609 The WPA Supplicant package to use.
13611 @item @code{dbus?} (default: @code{#t})
13612 Whether to listen for requests on D-Bus.
13614 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
13615 Where to store the PID file.
13617 @item @code{interface} (default: @code{#f})
13618 If this is set, it must specify the name of a network interface that
13619 WPA supplicant will control.
13621 @item @code{config-file} (default: @code{#f})
13622 Optional configuration file to use.
13624 @item @code{extra-options} (default: @code{'()})
13625 List of additional command-line arguments to pass to the daemon.
13630 @defvr {Scheme Variable} iptables-service-type
13631 This is the service type to set up an iptables configuration. iptables is a
13632 packet filtering framework supported by the Linux kernel. This service
13633 supports configuring iptables for both IPv4 and IPv6. A simple example
13634 configuration rejecting all incoming connections except those to the ssh port
13638 (service iptables-service-type
13639 (iptables-configuration
13640 (ipv4-rules (plain-file "iptables.rules" "*filter
13644 -A INPUT -p tcp --dport 22 -j ACCEPT
13645 -A INPUT -j REJECT --reject-with icmp-port-unreachable
13648 (ipv6-rules (plain-file "ip6tables.rules" "*filter
13652 -A INPUT -p tcp --dport 22 -j ACCEPT
13653 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
13659 @deftp {Data Type} iptables-configuration
13660 The data type representing the configuration of iptables.
13663 @item @code{iptables} (default: @code{iptables})
13664 The iptables package that provides @code{iptables-restore} and
13665 @code{ip6tables-restore}.
13666 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
13667 The iptables rules to use. It will be passed to @code{iptables-restore}.
13668 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13670 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
13671 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
13672 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13678 @defvr {Scheme Variable} nftables-service-type
13679 This is the service type to set up a nftables configuration. nftables is a
13680 netfilter project that aims to replace the existing iptables, ip6tables,
13681 arptables and ebtables framework. It provides a new packet filtering
13682 framework, a new user-space utility @command{nft}, and a compatibility layer
13683 for iptables. This service comes with a default ruleset
13684 @code{%default-nftables-ruleset} that rejecting all incomming connections
13685 except those to the ssh port 22. To use it, simply write:
13688 (service nftables-service-type)
13692 @deftp {Data Type} nftables-configuration
13693 The data type representing the configuration of nftables.
13696 @item @code{package} (default: @code{nftables})
13697 The nftables package that provides @command{nft}.
13698 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
13699 The nftables ruleset to use. This may be any ``file-like'' object
13700 (@pxref{G-Expressions, file-like objects}).
13704 @cindex NTP (Network Time Protocol), service
13705 @cindex ntpd, service for the Network Time Protocol daemon
13706 @cindex real time clock
13707 @defvr {Scheme Variable} ntp-service-type
13708 This is the type of the service running the @uref{https://www.ntp.org,
13709 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
13710 system clock synchronized with that of the specified NTP servers.
13712 The value of this service is an @code{ntpd-configuration} object, as described
13716 @deftp {Data Type} ntp-configuration
13717 This is the data type for the NTP service configuration.
13720 @item @code{servers} (default: @code{%ntp-servers})
13721 This is the list of servers (@code{<ntp-server>} records) with which
13722 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
13725 @item @code{allow-large-adjustment?} (default: @code{#t})
13726 This determines whether @command{ntpd} is allowed to make an initial
13727 adjustment of more than 1,000 seconds.
13729 @item @code{ntp} (default: @code{ntp})
13730 The NTP package to use.
13734 @defvr {Scheme Variable} %ntp-servers
13735 List of host names used as the default NTP servers. These are servers of the
13736 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
13739 @deftp {Data Type} ntp-server
13740 The data type representing the configuration of a NTP server.
13743 @item @code{type} (default: @code{'server})
13744 The type of the NTP server, given as a symbol. One of @code{'pool},
13745 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
13747 @item @code{address}
13748 The address of the server, as a string.
13750 @item @code{options}
13751 NTPD options to use with that specific server, given as a list of option names
13752 and/or of option names and values tuples. The following example define a server
13753 to use with the options @option{iburst} and @option{prefer}, as well as
13754 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
13759 (address "some.ntp.server.org")
13760 (options `(iburst (version 3) (maxpoll 16) prefer))))
13766 @deffn {Scheme Procedure} openntpd-service-type
13767 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
13768 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
13769 clock synchronized with that of the given servers.
13773 openntpd-service-type
13774 (openntpd-configuration
13775 (listen-on '("127.0.0.1" "::1"))
13776 (sensor '("udcf0 correction 70000"))
13777 (constraint-from '("www.gnu.org"))
13778 (constraints-from '("https://www.google.com/"))
13779 (allow-large-adjustment? #t)))
13784 @defvr {Scheme Variable} %openntpd-servers
13785 This variable is a list of the server addresses defined in
13786 @code{%ntp-servers}.
13789 @deftp {Data Type} openntpd-configuration
13791 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
13792 The openntpd executable to use.
13793 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
13794 A list of local IP addresses or hostnames the ntpd daemon should listen on.
13795 @item @code{query-from} (default: @code{'()})
13796 A list of local IP address the ntpd daemon should use for outgoing queries.
13797 @item @code{sensor} (default: @code{'()})
13798 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
13799 will listen to each sensor that actually exists and ignore non-existent ones.
13800 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
13802 @item @code{server} (default: @code{'()})
13803 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
13804 @item @code{servers} (default: @code{%openntp-servers})
13805 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
13806 @item @code{constraint-from} (default: @code{'()})
13807 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
13808 This time information is not used for precision but acts as an authenticated
13809 constraint, thereby reducing the impact of unauthenticated NTP
13810 man-in-the-middle attacks.
13811 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
13813 @item @code{constraints-from} (default: @code{'()})
13814 As with constraint from, specify a list of URLs, IP addresses or hostnames of
13815 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
13816 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
13817 @item @code{allow-large-adjustment?} (default: @code{#f})
13818 Determines if @code{ntpd} is allowed to make an initial adjustment of more
13824 @deffn {Scheme variable} inetd-service-type
13825 This service runs the @command{inetd} (@pxref{inetd invocation,,,
13826 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
13827 connections on internet sockets, and lazily starts the specified server
13828 program when a connection is made on one of these sockets.
13830 The value of this service is an @code{inetd-configuration} object. The
13831 following example configures the @command{inetd} daemon to provide the
13832 built-in @command{echo} service, as well as an smtp service which
13833 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
13834 gateway @code{hostname}:
13839 (inetd-configuration
13843 (socket-type 'stream)
13850 (socket-type 'stream)
13854 (program (file-append openssh "/bin/ssh"))
13856 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13857 "-W" "smtp-server:25" "user@@hostname")))))))
13860 See below for more details about @code{inetd-configuration}.
13863 @deftp {Data Type} inetd-configuration
13864 Data type representing the configuration of @command{inetd}.
13867 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13868 The @command{inetd} executable to use.
13870 @item @code{entries} (default: @code{'()})
13871 A list of @command{inetd} service entries. Each entry should be created
13872 by the @code{inetd-entry} constructor.
13876 @deftp {Data Type} inetd-entry
13877 Data type representing an entry in the @command{inetd} configuration.
13878 Each entry corresponds to a socket where @command{inetd} will listen for
13882 @item @code{node} (default: @code{#f})
13883 Optional string, a comma-separated list of local addresses
13884 @command{inetd} should use when listening for this service.
13885 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13886 description of all options.
13888 A string, the name must correspond to an entry in @code{/etc/services}.
13889 @item @code{socket-type}
13890 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13892 @item @code{protocol}
13893 A string, must correspond to an entry in @code{/etc/protocols}.
13894 @item @code{wait?} (default: @code{#t})
13895 Whether @command{inetd} should wait for the server to exit before
13896 listening to new service requests.
13898 A string containing the user (and, optionally, group) name of the user
13899 as whom the server should run. The group name can be specified in a
13900 suffix, separated by a colon or period, i.e.@: @code{"user"},
13901 @code{"user:group"} or @code{"user.group"}.
13902 @item @code{program} (default: @code{"internal"})
13903 The server program which will serve the requests, or @code{"internal"}
13904 if @command{inetd} should use a built-in service.
13905 @item @code{arguments} (default: @code{'()})
13906 A list strings or file-like objects, which are the server program's
13907 arguments, starting with the zeroth argument, i.e.@: the name of the
13908 program itself. For @command{inetd}'s internal services, this entry
13909 must be @code{'()} or @code{'("internal")}.
13912 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13913 detailed discussion of each configuration field.
13917 @defvr {Scheme Variable} tor-service-type
13918 This is the type for a service that runs the @uref{https://torproject.org,
13919 Tor} anonymous networking daemon. The service is configured using a
13920 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
13921 @code{tor} unprivileged user, which is a member of the @code{tor} group.
13925 @deftp {Data Type} tor-configuration
13927 @item @code{tor} (default: @code{tor})
13928 The package that provides the Tor daemon. This package is expected to provide
13929 the daemon at @file{bin/tor} relative to its output directory. The default
13930 package is the @uref{https://www.torproject.org, Tor Project's}
13933 @item @code{config-file} (default: @code{(plain-file "empty" "")})
13934 The configuration file to use. It will be appended to a default configuration
13935 file, and the final configuration file will be passed to @code{tor} via its
13936 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
13937 file-like objects}). See @code{man tor} for details on the configuration file
13940 @item @code{hidden-services} (default: @code{'()})
13941 The list of @code{<hidden-service>} records to use. For any hidden service
13942 you include in this list, appropriate configuration to enable the hidden
13943 service will be automatically added to the default configuration file. You
13944 may conveniently create @code{<hidden-service>} records using the
13945 @code{tor-hidden-service} procedure described below.
13947 @item @code{socks-socket-type} (default: @code{'tcp})
13948 The default socket type that Tor should use for its SOCKS socket. This must
13949 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
13950 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
13951 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
13952 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13955 If you want to customize the SOCKS socket in more detail, leave
13956 @code{socks-socket-type} at its default value of @code{'tcp} and use
13957 @code{config-file} to override the default by providing your own
13958 @code{SocksPort} option.
13962 @cindex hidden service
13963 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13964 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13965 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13968 '((22 "127.0.0.1:22")
13969 (80 "127.0.0.1:8080"))
13972 In this example, port 22 of the hidden service is mapped to local port 22, and
13973 port 80 is mapped to local port 8080.
13975 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13976 the @file{hostname} file contains the @code{.onion} host name for the hidden
13979 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13980 project's documentation} for more information.
13983 The @code{(gnu services rsync)} module provides the following services:
13985 You might want an rsync daemon if you have files that you want available
13986 so anyone (or just yourself) can download existing files or upload new
13989 @deffn {Scheme Variable} rsync-service-type
13990 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13991 The value for this service type is a
13992 @command{rsync-configuration} record as in this example:
13995 (service rsync-service-type)
13998 See below for details about @code{rsync-configuration}.
14001 @deftp {Data Type} rsync-configuration
14002 Data type representing the configuration for @code{rsync-service}.
14005 @item @code{package} (default: @var{rsync})
14006 @code{rsync} package to use.
14008 @item @code{port-number} (default: @code{873})
14009 TCP port on which @command{rsync} listens for incoming connections. If port
14010 is less than @code{1024} @command{rsync} needs to be started as the
14011 @code{root} user and group.
14013 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
14014 Name of the file where @command{rsync} writes its PID.
14016 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
14017 Name of the file where @command{rsync} writes its lock file.
14019 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
14020 Name of the file where @command{rsync} writes its log file.
14022 @item @code{use-chroot?} (default: @var{#t})
14023 Whether to use chroot for @command{rsync} shared directory.
14025 @item @code{share-path} (default: @file{/srv/rsync})
14026 Location of the @command{rsync} shared directory.
14028 @item @code{share-comment} (default: @code{"Rsync share"})
14029 Comment of the @command{rsync} shared directory.
14031 @item @code{read-only?} (default: @var{#f})
14032 Read-write permissions to shared directory.
14034 @item @code{timeout} (default: @code{300})
14035 I/O timeout in seconds.
14037 @item @code{user} (default: @var{"root"})
14038 Owner of the @code{rsync} process.
14040 @item @code{group} (default: @var{"root"})
14041 Group of the @code{rsync} process.
14043 @item @code{uid} (default: @var{"rsyncd"})
14044 User name or user ID that file transfers to and from that module should take
14045 place as when the daemon was run as @code{root}.
14047 @item @code{gid} (default: @var{"rsyncd"})
14048 Group name or group ID that will be used when accessing the module.
14053 Furthermore, @code{(gnu services ssh)} provides the following services.
14057 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
14058 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
14059 [#:allow-empty-passwords? #f] [#:root-login? #f] @
14060 [#:syslog-output? #t] [#:x11-forwarding? #t] @
14061 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
14062 [#:public-key-authentication? #t] [#:initialize? #t]
14063 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
14064 @var{host-key} must designate a file containing the host key, and readable
14067 When @var{daemonic?} is true, @command{lshd} will detach from the
14068 controlling terminal and log its output to syslogd, unless one sets
14069 @var{syslog-output?} to false. Obviously, it also makes lsh-service
14070 depend on existence of syslogd service. When @var{pid-file?} is true,
14071 @command{lshd} writes its PID to the file called @var{pid-file}.
14073 When @var{initialize?} is true, automatically create the seed and host key
14074 upon service activation if they do not exist yet. This may take long and
14075 require interaction.
14077 When @var{initialize?} is false, it is up to the user to initialize the
14078 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
14079 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
14080 basics,,, lsh, LSH Manual}).
14082 When @var{interfaces} is empty, lshd listens for connections on all the
14083 network interfaces; otherwise, @var{interfaces} must be a list of host names
14086 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
14087 passwords, and @var{root-login?} specifies whether to accept log-ins as
14090 The other options should be self-descriptive.
14095 @deffn {Scheme Variable} openssh-service-type
14096 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
14097 shell daemon, @command{sshd}. Its value must be an
14098 @code{openssh-configuration} record as in this example:
14101 (service openssh-service-type
14102 (openssh-configuration
14103 (x11-forwarding? #t)
14104 (permit-root-login 'without-password)
14106 `(("alice" ,(local-file "alice.pub"))
14107 ("bob" ,(local-file "bob.pub"))))))
14110 See below for details about @code{openssh-configuration}.
14112 This service can be extended with extra authorized keys, as in this
14116 (service-extension openssh-service-type
14117 (const `(("charlie"
14118 ,(local-file "charlie.pub")))))
14122 @deftp {Data Type} openssh-configuration
14123 This is the configuration record for OpenSSH's @command{sshd}.
14126 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
14127 Name of the file where @command{sshd} writes its PID.
14129 @item @code{port-number} (default: @code{22})
14130 TCP port on which @command{sshd} listens for incoming connections.
14132 @item @code{permit-root-login} (default: @code{#f})
14133 This field determines whether and when to allow logins as root. If
14134 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
14135 If it's the symbol @code{'without-password}, then root logins are
14136 permitted but not with password-based authentication.
14138 @item @code{allow-empty-passwords?} (default: @code{#f})
14139 When true, users with empty passwords may log in. When false, they may
14142 @item @code{password-authentication?} (default: @code{#t})
14143 When true, users may log in with their password. When false, they have
14144 other authentication methods.
14146 @item @code{public-key-authentication?} (default: @code{#t})
14147 When true, users may log in using public key authentication. When
14148 false, users have to use other authentication method.
14150 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
14151 This is used only by protocol version 2.
14153 @item @code{x11-forwarding?} (default: @code{#f})
14154 When true, forwarding of X11 graphical client connections is
14155 enabled---in other words, @command{ssh} options @option{-X} and
14156 @option{-Y} will work.
14158 @item @code{allow-agent-forwarding?} (default: @code{#t})
14159 Whether to allow agent forwarding.
14161 @item @code{allow-tcp-forwarding?} (default: @code{#t})
14162 Whether to allow TCP forwarding.
14164 @item @code{gateway-ports?} (default: @code{#f})
14165 Whether to allow gateway ports.
14167 @item @code{challenge-response-authentication?} (default: @code{#f})
14168 Specifies whether challenge response authentication is allowed (e.g.@: via
14171 @item @code{use-pam?} (default: @code{#t})
14172 Enables the Pluggable Authentication Module interface. If set to
14173 @code{#t}, this will enable PAM authentication using
14174 @code{challenge-response-authentication?} and
14175 @code{password-authentication?}, in addition to PAM account and session
14176 module processing for all authentication types.
14178 Because PAM challenge response authentication usually serves an
14179 equivalent role to password authentication, you should disable either
14180 @code{challenge-response-authentication?} or
14181 @code{password-authentication?}.
14183 @item @code{print-last-log?} (default: @code{#t})
14184 Specifies whether @command{sshd} should print the date and time of the
14185 last user login when a user logs in interactively.
14187 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
14188 Configures external subsystems (e.g.@: file transfer daemon).
14190 This is a list of two-element lists, each of which containing the
14191 subsystem name and a command (with optional arguments) to execute upon
14194 The command @command{internal-sftp} implements an in-process SFTP
14195 server. Alternately, one can specify the @command{sftp-server} command:
14197 (service openssh-service-type
14198 (openssh-configuration
14200 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
14203 @item @code{accepted-environment} (default: @code{'()})
14204 List of strings describing which environment variables may be exported.
14206 Each string gets on its own line. See the @code{AcceptEnv} option in
14207 @code{man sshd_config}.
14209 This example allows ssh-clients to export the @code{COLORTERM} variable.
14210 It is set by terminal emulators, which support colors. You can use it in
14211 your shell's resource file to enable colors for the prompt and commands
14212 if this variable is set.
14215 (service openssh-service-type
14216 (openssh-configuration
14217 (accepted-environment '("COLORTERM"))))
14220 @item @code{authorized-keys} (default: @code{'()})
14221 @cindex authorized keys, SSH
14222 @cindex SSH authorized keys
14223 This is the list of authorized keys. Each element of the list is a user
14224 name followed by one or more file-like objects that represent SSH public
14228 (openssh-configuration
14230 `(("rekado" ,(local-file "rekado.pub"))
14231 ("chris" ,(local-file "chris.pub"))
14232 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
14236 registers the specified public keys for user accounts @code{rekado},
14237 @code{chris}, and @code{root}.
14239 Additional authorized keys can be specified @i{via}
14240 @code{service-extension}.
14242 Note that this does @emph{not} interfere with the use of
14243 @file{~/.ssh/authorized_keys}.
14245 @item @code{log-level} (default: @code{'info})
14246 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
14247 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
14248 page for @file{sshd_config} for the full list of level names.
14250 @item @code{extra-content} (default: @code{""})
14251 This field can be used to append arbitrary text to the configuration file. It
14252 is especially useful for elaborate configurations that cannot be expressed
14253 otherwise. This configuration, for example, would generally disable root
14254 logins, but permit them from one specific IP address:
14257 (openssh-configuration
14259 Match Address 192.168.0.1
14260 PermitRootLogin yes"))
14266 @deffn {Scheme Procedure} dropbear-service [@var{config}]
14267 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
14268 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
14271 For example, to specify a Dropbear service listening on port 1234, add
14272 this call to the operating system's @code{services} field:
14275 (dropbear-service (dropbear-configuration
14276 (port-number 1234)))
14280 @deftp {Data Type} dropbear-configuration
14281 This data type represents the configuration of a Dropbear SSH daemon.
14284 @item @code{dropbear} (default: @var{dropbear})
14285 The Dropbear package to use.
14287 @item @code{port-number} (default: 22)
14288 The TCP port where the daemon waits for incoming connections.
14290 @item @code{syslog-output?} (default: @code{#t})
14291 Whether to enable syslog output.
14293 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
14294 File name of the daemon's PID file.
14296 @item @code{root-login?} (default: @code{#f})
14297 Whether to allow @code{root} logins.
14299 @item @code{allow-empty-passwords?} (default: @code{#f})
14300 Whether to allow empty passwords.
14302 @item @code{password-authentication?} (default: @code{#t})
14303 Whether to enable password-based authentication.
14307 @defvr {Scheme Variable} %facebook-host-aliases
14308 This variable contains a string for use in @file{/etc/hosts}
14309 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
14310 line contains a entry that maps a known server name of the Facebook
14311 on-line service---e.g., @code{www.facebook.com}---to the local
14312 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
14314 This variable is typically used in the @code{hosts-file} field of an
14315 @code{operating-system} declaration (@pxref{operating-system Reference,
14316 @file{/etc/hosts}}):
14319 (use-modules (gnu) (guix))
14322 (host-name "mymachine")
14325 ;; Create a /etc/hosts file with aliases for "localhost"
14326 ;; and "mymachine", as well as for Facebook servers.
14327 (plain-file "hosts"
14328 (string-append (local-host-aliases host-name)
14329 %facebook-host-aliases))))
14332 This mechanism can prevent programs running locally, such as Web
14333 browsers, from accessing Facebook.
14336 The @code{(gnu services avahi)} provides the following definition.
14338 @defvr {Scheme Variable} avahi-service-type
14339 This is the service that runs @command{avahi-daemon}, a system-wide
14340 mDNS/DNS-SD responder that allows for service discovery and
14341 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
14342 Its value must be a @code{zero-configuration} record---see below.
14344 This service extends the name service cache daemon (nscd) so that it can
14345 resolve @code{.local} host names using
14346 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
14347 Service Switch}, for information on host name resolution.
14349 Additionally, add the @var{avahi} package to the system profile so that
14350 commands such as @command{avahi-browse} are directly usable.
14353 @deftp {Data Type} avahi-configuration
14354 Data type representation the configuration for Avahi.
14358 @item @code{host-name} (default: @code{#f})
14359 If different from @code{#f}, use that as the host name to
14360 publish for this machine; otherwise, use the machine's actual host name.
14362 @item @code{publish?} (default: @code{#t})
14363 When true, allow host names and services to be published (broadcast) over the
14366 @item @code{publish-workstation?} (default: @code{#t})
14367 When true, @command{avahi-daemon} publishes the machine's host name and IP
14368 address via mDNS on the local network. To view the host names published on
14369 your local network, you can run:
14372 avahi-browse _workstation._tcp
14375 @item @code{wide-area?} (default: @code{#f})
14376 When true, DNS-SD over unicast DNS is enabled.
14378 @item @code{ipv4?} (default: @code{#t})
14379 @itemx @code{ipv6?} (default: @code{#t})
14380 These fields determine whether to use IPv4/IPv6 sockets.
14382 @item @code{domains-to-browse} (default: @code{'()})
14383 This is a list of domains to browse.
14387 @deffn {Scheme Variable} openvswitch-service-type
14388 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
14389 service, whose value should be an @code{openvswitch-configuration}
14393 @deftp {Data Type} openvswitch-configuration
14394 Data type representing the configuration of Open vSwitch, a multilayer
14395 virtual switch which is designed to enable massive network automation
14396 through programmatic extension.
14399 @item @code{package} (default: @var{openvswitch})
14400 Package object of the Open vSwitch.
14405 @defvr {Scheme Variable} pagekite-service-type
14406 This is the service type for the @uref{https://pagekite.net, PageKite} service,
14407 a tunneling solution for making localhost servers publicly visible, even from
14408 behind restrictive firewalls or NAT without forwarded ports. The value for
14409 this service type is a @code{pagekite-configuration} record.
14411 Here's an example exposing the local HTTP and SSH daemons:
14414 (service pagekite-service-type
14415 (pagekite-configuration
14416 (kites '("http:@@kitename:localhost:80:@@kitesecret"
14417 "raw/22:@@kitename:localhost:22:@@kitesecret"))
14418 (extra-file "/etc/pagekite.rc")))
14422 @deftp {Data Type} pagekite-configuration
14423 Data type representing the configuration of PageKite.
14426 @item @code{package} (default: @var{pagekite})
14427 Package object of PageKite.
14429 @item @code{kitename} (default: @code{#f})
14430 PageKite name for authenticating to the frontend server.
14432 @item @code{kitesecret} (default: @code{#f})
14433 Shared secret for authenticating to the frontend server. You should probably
14434 put this inside @code{extra-file} instead.
14436 @item @code{frontend} (default: @code{#f})
14437 Connect to the named PageKite frontend server instead of the
14438 @uref{https://pagekite.net,,pagekite.net} service.
14440 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
14441 List of service kites to use. Exposes HTTP on port 80 by default. The format
14442 is @code{proto:kitename:host:port:secret}.
14444 @item @code{extra-file} (default: @code{#f})
14445 Extra configuration file to read, which you are expected to create manually.
14446 Use this to add additional options and manage shared secrets out-of-band.
14452 @subsection X Window
14455 @cindex X Window System
14456 @cindex login manager
14457 Support for the X Window graphical display system---specifically
14458 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
14459 there is no @code{xorg-service} procedure. Instead, the X server is
14460 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
14463 @cindex GNOME, login manager
14464 GDM of course allows users to log in into window managers and desktop
14465 environments other than GNOME; for those using GNOME, GDM is required for
14466 features such as automatic screen locking.
14468 @cindex window manager
14469 To use X11, you must install at least one @dfn{window manager}---for
14470 example the @code{windowmaker} or @code{openbox} packages---preferably
14471 by adding it to the @code{packages} field of your operating system
14472 definition (@pxref{operating-system Reference, system-wide packages}).
14474 @defvr {Scheme Variable} gdm-service-type
14475 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
14476 Desktop Manager} (GDM), a program that manages graphical display servers and
14477 handles graphical user logins. Its value must be a @code{gdm-configuration}
14480 @cindex session types (X11)
14481 @cindex X11 session types
14482 GDM looks for @dfn{session types} described by the @file{.desktop} files in
14483 @file{/run/current-system/profile/share/xsessions} and allows users to choose
14484 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
14485 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
14486 set of packages automatically makes them available at the log-in screen.
14488 In addition, @file{~/.xsession} files are honored. When available,
14489 @file{~/.xsession} must be an executable that starts a window manager
14490 and/or other X clients.
14493 @deftp {Data Type} gdm-configuration
14495 @item @code{auto-login?} (default: @code{#f})
14496 @itemx @code{default-user} (default: @code{#f})
14497 When @code{auto-login?} is false, GDM presents a log-in screen.
14499 When @code{auto-login?} is true, GDM logs in directly as
14500 @code{default-user}.
14502 @item @code{debug?} (default: @code{#f})
14503 When true, GDM writes debug messages to its log.
14505 @item @code{gnome-shell-assets} (default: ...)
14506 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
14508 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
14509 Configuration of the Xorg graphical server.
14511 @item @code{xsession} (default: @code{(xinitrc)})
14512 Script to run before starting a X session.
14514 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
14515 File name of the @code{dbus-daemon} executable.
14517 @item @code{gdm} (default: @code{gdm})
14518 The GDM package to use.
14522 @defvr {Scheme Variable} slim-service-type
14523 This is the type for the SLiM graphical login manager for X11.
14525 Like GDM, SLiM looks for session types described by @file{.desktop} files and
14526 allows users to choose a session from the log-in screen using @kbd{F1}. It
14527 also honors @file{~/.xsession} files.
14529 Unlike GDM, SLiM does not spawn the user session on a different VT after
14530 logging in, which means that you can only start one graphical session. If you
14531 want to be able to run multiple graphical sessions at the same time you have
14532 to add multiple SLiM services to your system services. The following example
14533 shows how to replace the default GDM service with two SLiM services on tty7
14537 (use-modules (gnu services)
14538 (gnu services desktop)
14539 (gnu services xorg)
14540 (srfi srfi-1)) ;for 'remove'
14544 (services (cons* (service slim-service-type (slim-configuration
14547 (service slim-service-type (slim-configuration
14550 (remove (lambda (service)
14551 (eq? (service-kind service) gdm-service-type))
14552 %desktop-services))))
14557 @deftp {Data Type} slim-configuration
14558 Data type representing the configuration of @code{slim-service-type}.
14561 @item @code{allow-empty-passwords?} (default: @code{#t})
14562 Whether to allow logins with empty passwords.
14564 @item @code{auto-login?} (default: @code{#f})
14565 @itemx @code{default-user} (default: @code{""})
14566 When @code{auto-login?} is false, SLiM presents a log-in screen.
14568 When @code{auto-login?} is true, SLiM logs in directly as
14569 @code{default-user}.
14571 @item @code{theme} (default: @code{%default-slim-theme})
14572 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
14573 The graphical theme to use and its name.
14575 @item @code{auto-login-session} (default: @code{#f})
14576 If true, this must be the name of the executable to start as the default
14577 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
14579 If false, a session described by one of the available @file{.desktop}
14580 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
14584 You must install at least one window manager in the system profile or in
14585 your user profile. Failing to do that, if @code{auto-login-session} is
14586 false, you will be unable to log in.
14589 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14590 Configuration of the Xorg graphical server.
14592 @item @code{display} (default @code{":0"})
14593 The display on which to start the Xorg graphical server.
14595 @item @code{vt} (default @code{"vt7"})
14596 The VT on which to start the Xorg graphical server.
14598 @item @code{xauth} (default: @code{xauth})
14599 The XAuth package to use.
14601 @item @code{shepherd} (default: @code{shepherd})
14602 The Shepherd package used when invoking @command{halt} and
14605 @item @code{sessreg} (default: @code{sessreg})
14606 The sessreg package used in order to register the session.
14608 @item @code{slim} (default: @code{slim})
14609 The SLiM package to use.
14613 @defvr {Scheme Variable} %default-theme
14614 @defvrx {Scheme Variable} %default-theme-name
14615 The default SLiM theme and its name.
14619 @deftp {Data Type} sddm-configuration
14620 This is the data type representing the sddm service configuration.
14623 @item @code{display-server} (default: "x11")
14624 Select display server to use for the greeter. Valid values are "x11"
14627 @item @code{numlock} (default: "on")
14628 Valid values are "on", "off" or "none".
14630 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
14631 Command to run when halting.
14633 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
14634 Command to run when rebooting.
14636 @item @code{theme} (default "maldives")
14637 Theme to use. Default themes provided by SDDM are "elarun", "maldives" or "maya".
14639 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
14640 Directory to look for themes.
14642 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
14643 Directory to look for faces.
14645 @item @code{default-path} (default "/run/current-system/profile/bin")
14646 Default PATH to use.
14648 @item @code{minimum-uid} (default: 1000)
14649 Minimum UID displayed in SDDM and allowed for log-in.
14651 @item @code{maximum-uid} (default: 2000)
14652 Maximum UID to display in SDDM.
14654 @item @code{remember-last-user?} (default #t)
14655 Remember last user.
14657 @item @code{remember-last-session?} (default #t)
14658 Remember last session.
14660 @item @code{hide-users} (default "")
14661 Usernames to hide from SDDM greeter.
14663 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
14664 Users with shells listed will be hidden from the SDDM greeter.
14666 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
14667 Script to run before starting a wayland session.
14669 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
14670 Directory to look for desktop files starting wayland sessions.
14672 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14673 Configuration of the Xorg graphical server.
14675 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
14678 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
14681 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
14682 Script to run after starting xorg-server.
14684 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
14685 Script to run before stopping xorg-server.
14687 @item @code{xsession-command} (default: @code{xinitrc})
14688 Script to run before starting a X session.
14690 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
14691 Directory to look for desktop files starting X sessions.
14693 @item @code{minimum-vt} (default: 7)
14696 @item @code{auto-login-user} (default "")
14697 User to use for auto-login.
14699 @item @code{auto-login-session} (default "")
14700 Desktop file to use for auto-login.
14702 @item @code{relogin?} (default #f)
14703 Relogin after logout.
14708 @cindex login manager
14710 @defvr {Scheme Variable} sddm-service-type
14711 This is the type of the service to run the
14712 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
14713 must be a @code{sddm-configuration} record (see below).
14715 Here's an example use:
14718 (service sddm-service-type
14719 (sddm-configuration
14720 (auto-login-user "alice")
14721 (auto-login-session "xfce.desktop")))
14725 @deftp {Data Type} sddm-configuration
14726 This data type represents the configuration of the SDDM login manager.
14727 The available fields are:
14730 @item @code{sddm} (default: @code{sddm})
14731 The SDDM package to use.
14733 @item @code{display-server} (default: @code{"x11"})
14734 This must be either @code{"x11"} or @code{"wayland"}.
14736 @c FIXME: Add more fields.
14738 @item @code{auto-login-user} (default: @code{""})
14739 If non-empty, this is the user account under which to log in
14742 @item @code{auto-login-session} (default: @code{""})
14743 If non-empty, this is the @file{.desktop} file name to use as the
14744 auto-login session.
14748 @cindex Xorg, configuration
14749 @deftp {Data Type} xorg-configuration
14750 This data type represents the configuration of the Xorg graphical display
14751 server. Note that there is not Xorg service; instead, the X server is started
14752 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
14753 of these display managers aggregates an @code{xorg-configuration} record.
14756 @item @code{modules} (default: @code{%default-xorg-modules})
14757 This is a list of @dfn{module packages} loaded by the Xorg
14758 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
14760 @item @code{fonts} (default: @code{%default-xorg-fonts})
14761 This is a list of font directories to add to the server's @dfn{font path}.
14763 @item @code{drivers} (default: @code{'()})
14764 This must be either the empty list, in which case Xorg chooses a graphics
14765 driver automatically, or a list of driver names that will be tried in this
14766 order---e.g., @code{("modesetting" "vesa")}.
14768 @item @code{resolutions} (default: @code{'()})
14769 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
14770 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
14773 @cindex keyboard layout, for Xorg
14774 @cindex keymap, for Xorg
14775 @item @code{keyboard-layout} (default: @code{#f})
14776 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
14777 English (``qwerty'') for a 105-key PC keyboard.
14779 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
14780 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
14781 information on how to specify the keyboard layout.
14783 @item @code{extra-config} (default: @code{'()})
14784 This is a list of strings or objects appended to the configuration file. It
14785 is used to pass extra text to be added verbatim to the configuration file.
14787 @item @code{server} (default: @code{xorg-server})
14788 This is the package providing the Xorg server.
14790 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
14791 This is the list of command-line arguments to pass to the X server. The
14792 default is @code{-nolisten tcp}.
14796 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
14797 [@var{login-manager-service-type}]
14798 Tell the log-in manager (of type @var{login-manager-service-type}) to use
14799 @var{config}, an @code{<xorg-configuration>} record.
14801 Since the Xorg configuration is embedded in the log-in manager's
14802 configuration---e.g., @code{gdm-configuration}---this procedure provides a
14803 shorthand to set the Xorg configuration.
14806 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
14807 Return a @code{startx} script in which the modules, fonts, etc. specified
14808 in @var{config}, are available. The result should be used in place of
14811 Usually the X server is started by a login manager.
14815 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
14816 Add @var{package}, a package for a screen locker or screen saver whose
14817 command is @var{program}, to the set of setuid programs and add a PAM entry
14818 for it. For example:
14821 (screen-locker-service xlockmore "xlock")
14824 makes the good ol' XlockMore usable.
14828 @node Printing Services
14829 @subsection Printing Services
14831 @cindex printer support with CUPS
14832 The @code{(gnu services cups)} module provides a Guix service definition
14833 for the CUPS printing service. To add printer support to a Guix
14834 system, add a @code{cups-service} to the operating system definition:
14836 @deffn {Scheme Variable} cups-service-type
14837 The service type for the CUPS print server. Its value should be a valid
14838 CUPS configuration (see below). To use the default settings, simply
14841 (service cups-service-type)
14845 The CUPS configuration controls the basic things about your CUPS
14846 installation: what interfaces it listens on, what to do if a print job
14847 fails, how much logging to do, and so on. To actually add a printer,
14848 you have to visit the @url{http://localhost:631} URL, or use a tool such
14849 as GNOME's printer configuration services. By default, configuring a
14850 CUPS service will generate a self-signed certificate if needed, for
14851 secure connections to the print server.
14853 Suppose you want to enable the Web interface of CUPS and also add
14854 support for Epson printers @i{via} the @code{escpr} package and for HP
14855 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
14856 like this (you need to use the @code{(gnu packages cups)} module):
14859 (service cups-service-type
14860 (cups-configuration
14861 (web-interface? #t)
14863 (list cups-filters escpr hplip-minimal))))
14866 Note: If you wish to use the Qt5 based GUI which comes with the hplip
14867 package then it is suggested that you install the @code{hplip} package,
14868 either in your OS configuration file or as your user.
14870 The available configuration parameters follow. Each parameter
14871 definition is preceded by its type; for example, @samp{string-list foo}
14872 indicates that the @code{foo} parameter should be specified as a list of
14873 strings. There is also a way to specify the configuration as a string,
14874 if you have an old @code{cupsd.conf} file that you want to port over
14875 from some other system; see the end for more details.
14877 @c The following documentation was initially generated by
14878 @c (generate-documentation) in (gnu services cups). Manually maintained
14879 @c documentation is better, so we shouldn't hesitate to edit below as
14880 @c needed. However if the change you want to make to this documentation
14881 @c can be done in an automated way, it's probably easier to change
14882 @c (generate-documentation) than to make it below and have to deal with
14883 @c the churn as CUPS updates.
14886 Available @code{cups-configuration} fields are:
14888 @deftypevr {@code{cups-configuration} parameter} package cups
14892 @deftypevr {@code{cups-configuration} parameter} package-list extensions
14893 Drivers and other extensions to the CUPS package.
14896 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
14897 Configuration of where to write logs, what directories to use for print
14898 spools, and related privileged configuration parameters.
14900 Available @code{files-configuration} fields are:
14902 @deftypevr {@code{files-configuration} parameter} log-location access-log
14903 Defines the access log filename. Specifying a blank filename disables
14904 access log generation. The value @code{stderr} causes log entries to be
14905 sent to the standard error file when the scheduler is running in the
14906 foreground, or to the system log daemon when run in the background. The
14907 value @code{syslog} causes log entries to be sent to the system log
14908 daemon. The server name may be included in filenames using the string
14909 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
14911 Defaults to @samp{"/var/log/cups/access_log"}.
14914 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
14915 Where CUPS should cache data.
14917 Defaults to @samp{"/var/cache/cups"}.
14920 @deftypevr {@code{files-configuration} parameter} string config-file-perm
14921 Specifies the permissions for all configuration files that the scheduler
14924 Note that the permissions for the printers.conf file are currently
14925 masked to only allow access from the scheduler user (typically root).
14926 This is done because printer device URIs sometimes contain sensitive
14927 authentication information that should not be generally known on the
14928 system. There is no way to disable this security feature.
14930 Defaults to @samp{"0640"}.
14933 @deftypevr {@code{files-configuration} parameter} log-location error-log
14934 Defines the error log filename. Specifying a blank filename disables
14935 error log generation. The value @code{stderr} causes log entries to be
14936 sent to the standard error file when the scheduler is running in the
14937 foreground, or to the system log daemon when run in the background. The
14938 value @code{syslog} causes log entries to be sent to the system log
14939 daemon. The server name may be included in filenames using the string
14940 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
14942 Defaults to @samp{"/var/log/cups/error_log"}.
14945 @deftypevr {@code{files-configuration} parameter} string fatal-errors
14946 Specifies which errors are fatal, causing the scheduler to exit. The
14951 No errors are fatal.
14954 All of the errors below are fatal.
14957 Browsing initialization errors are fatal, for example failed connections
14958 to the DNS-SD daemon.
14961 Configuration file syntax errors are fatal.
14964 Listen or Port errors are fatal, except for IPv6 failures on the
14965 loopback or @code{any} addresses.
14968 Log file creation or write errors are fatal.
14971 Bad startup file permissions are fatal, for example shared TLS
14972 certificate and key files with world-read permissions.
14975 Defaults to @samp{"all -browse"}.
14978 @deftypevr {@code{files-configuration} parameter} boolean file-device?
14979 Specifies whether the file pseudo-device can be used for new printer
14980 queues. The URI @uref{file:///dev/null} is always allowed.
14982 Defaults to @samp{#f}.
14985 @deftypevr {@code{files-configuration} parameter} string group
14986 Specifies the group name or ID that will be used when executing external
14989 Defaults to @samp{"lp"}.
14992 @deftypevr {@code{files-configuration} parameter} string log-file-perm
14993 Specifies the permissions for all log files that the scheduler writes.
14995 Defaults to @samp{"0644"}.
14998 @deftypevr {@code{files-configuration} parameter} log-location page-log
14999 Defines the page log filename. Specifying a blank filename disables
15000 page log generation. The value @code{stderr} causes log entries to be
15001 sent to the standard error file when the scheduler is running in the
15002 foreground, or to the system log daemon when run in the background. The
15003 value @code{syslog} causes log entries to be sent to the system log
15004 daemon. The server name may be included in filenames using the string
15005 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
15007 Defaults to @samp{"/var/log/cups/page_log"}.
15010 @deftypevr {@code{files-configuration} parameter} string remote-root
15011 Specifies the username that is associated with unauthenticated accesses
15012 by clients claiming to be the root user. The default is @code{remroot}.
15014 Defaults to @samp{"remroot"}.
15017 @deftypevr {@code{files-configuration} parameter} file-name request-root
15018 Specifies the directory that contains print jobs and other HTTP request
15021 Defaults to @samp{"/var/spool/cups"}.
15024 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
15025 Specifies the level of security sandboxing that is applied to print
15026 filters, backends, and other child processes of the scheduler; either
15027 @code{relaxed} or @code{strict}. This directive is currently only
15028 used/supported on macOS.
15030 Defaults to @samp{strict}.
15033 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
15034 Specifies the location of TLS certificates and private keys. CUPS will
15035 look for public and private keys in this directory: a @code{.crt} files
15036 for PEM-encoded certificates and corresponding @code{.key} files for
15037 PEM-encoded private keys.
15039 Defaults to @samp{"/etc/cups/ssl"}.
15042 @deftypevr {@code{files-configuration} parameter} file-name server-root
15043 Specifies the directory containing the server configuration files.
15045 Defaults to @samp{"/etc/cups"}.
15048 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
15049 Specifies whether the scheduler calls fsync(2) after writing
15050 configuration or state files.
15052 Defaults to @samp{#f}.
15055 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
15056 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
15059 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
15060 Specifies the directory where temporary files are stored.
15062 Defaults to @samp{"/var/spool/cups/tmp"}.
15065 @deftypevr {@code{files-configuration} parameter} string user
15066 Specifies the user name or ID that is used when running external
15069 Defaults to @samp{"lp"}.
15072 @deftypevr {@code{files-configuration} parameter} string set-env
15073 Set the specified environment variable to be passed to child processes.
15075 Defaults to @samp{"variable value"}.
15079 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
15080 Specifies the logging level for the AccessLog file. The @code{config}
15081 level logs when printers and classes are added, deleted, or modified and
15082 when configuration files are accessed or updated. The @code{actions}
15083 level logs when print jobs are submitted, held, released, modified, or
15084 canceled, and any of the conditions for @code{config}. The @code{all}
15085 level logs all requests.
15087 Defaults to @samp{actions}.
15090 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
15091 Specifies whether to purge job history data automatically when it is no
15092 longer required for quotas.
15094 Defaults to @samp{#f}.
15097 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
15098 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
15099 For example, @samp{"_cups" "_print"} will tell network clients that both
15100 CUPS sharing and IPP Everywhere are supported.
15102 Defaults to @samp{"_cups"}.
15105 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
15106 Specifies which protocols to use for local printer sharing.
15108 Defaults to @samp{dnssd}.
15111 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
15112 Specifies whether the CUPS web interface is advertised.
15114 Defaults to @samp{#f}.
15117 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
15118 Specifies whether shared printers are advertised.
15120 Defaults to @samp{#f}.
15123 @deftypevr {@code{cups-configuration} parameter} string classification
15124 Specifies the security classification of the server. Any valid banner
15125 name can be used, including "classified", "confidential", "secret",
15126 "topsecret", and "unclassified", or the banner can be omitted to disable
15127 secure printing functions.
15129 Defaults to @samp{""}.
15132 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
15133 Specifies whether users may override the classification (cover page) of
15134 individual print jobs using the @code{job-sheets} option.
15136 Defaults to @samp{#f}.
15139 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
15140 Specifies the default type of authentication to use.
15142 Defaults to @samp{Basic}.
15145 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
15146 Specifies whether encryption will be used for authenticated requests.
15148 Defaults to @samp{Required}.
15151 @deftypevr {@code{cups-configuration} parameter} string default-language
15152 Specifies the default language to use for text and web content.
15154 Defaults to @samp{"en"}.
15157 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
15158 Specifies the default paper size for new print queues. @samp{"Auto"}
15159 uses a locale-specific default, while @samp{"None"} specifies there is
15160 no default paper size. Specific size names are typically
15161 @samp{"Letter"} or @samp{"A4"}.
15163 Defaults to @samp{"Auto"}.
15166 @deftypevr {@code{cups-configuration} parameter} string default-policy
15167 Specifies the default access policy to use.
15169 Defaults to @samp{"default"}.
15172 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
15173 Specifies whether local printers are shared by default.
15175 Defaults to @samp{#t}.
15178 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
15179 Specifies the delay for updating of configuration and state files, in
15180 seconds. A value of 0 causes the update to happen as soon as possible,
15181 typically within a few milliseconds.
15183 Defaults to @samp{30}.
15186 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
15187 Specifies what to do when an error occurs. Possible values are
15188 @code{abort-job}, which will discard the failed print job;
15189 @code{retry-job}, which will retry the job at a later time;
15190 @code{retry-current-job}, which retries the failed job immediately; and
15191 @code{stop-printer}, which stops the printer.
15193 Defaults to @samp{stop-printer}.
15196 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
15197 Specifies the maximum cost of filters that are run concurrently, which
15198 can be used to minimize disk, memory, and CPU resource problems. A
15199 limit of 0 disables filter limiting. An average print to a
15200 non-PostScript printer needs a filter limit of about 200. A PostScript
15201 printer needs about half that (100). Setting the limit below these
15202 thresholds will effectively limit the scheduler to printing a single job
15205 Defaults to @samp{0}.
15208 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
15209 Specifies the scheduling priority of filters that are run to print a
15210 job. The nice value ranges from 0, the highest priority, to 19, the
15213 Defaults to @samp{0}.
15216 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
15217 Specifies whether to do reverse lookups on connecting clients. The
15218 @code{double} setting causes @code{cupsd} to verify that the hostname
15219 resolved from the address matches one of the addresses returned for that
15220 hostname. Double lookups also prevent clients with unregistered
15221 addresses from connecting to your server. Only set this option to
15222 @code{#t} or @code{double} if absolutely required.
15224 Defaults to @samp{#f}.
15227 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
15228 Specifies the number of seconds to wait before killing the filters and
15229 backend associated with a canceled or held job.
15231 Defaults to @samp{30}.
15234 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
15235 Specifies the interval between retries of jobs in seconds. This is
15236 typically used for fax queues but can also be used with normal print
15237 queues whose error policy is @code{retry-job} or
15238 @code{retry-current-job}.
15240 Defaults to @samp{30}.
15243 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
15244 Specifies the number of retries that are done for jobs. This is
15245 typically used for fax queues but can also be used with normal print
15246 queues whose error policy is @code{retry-job} or
15247 @code{retry-current-job}.
15249 Defaults to @samp{5}.
15252 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
15253 Specifies whether to support HTTP keep-alive connections.
15255 Defaults to @samp{#t}.
15258 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
15259 Specifies how long an idle client connection remains open, in seconds.
15261 Defaults to @samp{30}.
15264 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
15265 Specifies the maximum size of print files, IPP requests, and HTML form
15266 data. A limit of 0 disables the limit check.
15268 Defaults to @samp{0}.
15271 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
15272 Listens on the specified interfaces for connections. Valid values are
15273 of the form @var{address}:@var{port}, where @var{address} is either an
15274 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
15275 indicate all addresses. Values can also be file names of local UNIX
15276 domain sockets. The Listen directive is similar to the Port directive
15277 but allows you to restrict access to specific interfaces or networks.
15280 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
15281 Specifies the number of pending connections that will be allowed. This
15282 normally only affects very busy servers that have reached the MaxClients
15283 limit, but can also be triggered by large numbers of simultaneous
15284 connections. When the limit is reached, the operating system will
15285 refuse additional connections until the scheduler can accept the pending
15288 Defaults to @samp{128}.
15291 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
15292 Specifies a set of additional access controls.
15294 Available @code{location-access-controls} fields are:
15296 @deftypevr {@code{location-access-controls} parameter} file-name path
15297 Specifies the URI path to which the access control applies.
15300 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
15301 Access controls for all access to this path, in the same format as the
15302 @code{access-controls} of @code{operation-access-control}.
15304 Defaults to @samp{()}.
15307 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
15308 Access controls for method-specific access to this path.
15310 Defaults to @samp{()}.
15312 Available @code{method-access-controls} fields are:
15314 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
15315 If @code{#t}, apply access controls to all methods except the listed
15316 methods. Otherwise apply to only the listed methods.
15318 Defaults to @samp{#f}.
15321 @deftypevr {@code{method-access-controls} parameter} method-list methods
15322 Methods to which this access control applies.
15324 Defaults to @samp{()}.
15327 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
15328 Access control directives, as a list of strings. Each string should be
15329 one directive, such as "Order allow,deny".
15331 Defaults to @samp{()}.
15336 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
15337 Specifies the number of debugging messages that are retained for logging
15338 if an error occurs in a print job. Debug messages are logged regardless
15339 of the LogLevel setting.
15341 Defaults to @samp{100}.
15344 @deftypevr {@code{cups-configuration} parameter} log-level log-level
15345 Specifies the level of logging for the ErrorLog file. The value
15346 @code{none} stops all logging while @code{debug2} logs everything.
15348 Defaults to @samp{info}.
15351 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
15352 Specifies the format of the date and time in the log files. The value
15353 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
15355 Defaults to @samp{standard}.
15358 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
15359 Specifies the maximum number of simultaneous clients that are allowed by
15362 Defaults to @samp{100}.
15365 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
15366 Specifies the maximum number of simultaneous clients that are allowed
15367 from a single address.
15369 Defaults to @samp{100}.
15372 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
15373 Specifies the maximum number of copies that a user can print of each
15376 Defaults to @samp{9999}.
15379 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
15380 Specifies the maximum time a job may remain in the @code{indefinite}
15381 hold state before it is canceled. A value of 0 disables cancellation of
15384 Defaults to @samp{0}.
15387 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
15388 Specifies the maximum number of simultaneous jobs that are allowed. Set
15389 to 0 to allow an unlimited number of jobs.
15391 Defaults to @samp{500}.
15394 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
15395 Specifies the maximum number of simultaneous jobs that are allowed per
15396 printer. A value of 0 allows up to MaxJobs jobs per printer.
15398 Defaults to @samp{0}.
15401 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
15402 Specifies the maximum number of simultaneous jobs that are allowed per
15403 user. A value of 0 allows up to MaxJobs jobs per user.
15405 Defaults to @samp{0}.
15408 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
15409 Specifies the maximum time a job may take to print before it is
15410 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
15412 Defaults to @samp{10800}.
15415 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
15416 Specifies the maximum size of the log files before they are rotated, in
15417 bytes. The value 0 disables log rotation.
15419 Defaults to @samp{1048576}.
15422 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
15423 Specifies the maximum amount of time to allow between files in a
15424 multiple file print job, in seconds.
15426 Defaults to @samp{300}.
15429 @deftypevr {@code{cups-configuration} parameter} string page-log-format
15430 Specifies the format of PageLog lines. Sequences beginning with percent
15431 (@samp{%}) characters are replaced with the corresponding information,
15432 while all other characters are copied literally. The following percent
15433 sequences are recognized:
15437 insert a single percent character
15440 insert the value of the specified IPP attribute
15443 insert the number of copies for the current page
15446 insert the current page number
15449 insert the current date and time in common log format
15455 insert the printer name
15458 insert the username
15461 A value of the empty string disables page logging. The string @code{%p
15462 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
15463 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
15466 Defaults to @samp{""}.
15469 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
15470 Passes the specified environment variable(s) to child processes; a list
15473 Defaults to @samp{()}.
15476 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
15477 Specifies named access control policies.
15479 Available @code{policy-configuration} fields are:
15481 @deftypevr {@code{policy-configuration} parameter} string name
15482 Name of the policy.
15485 @deftypevr {@code{policy-configuration} parameter} string job-private-access
15486 Specifies an access list for a job's private values. @code{@@ACL} maps
15487 to the printer's requesting-user-name-allowed or
15488 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15489 owner. @code{@@SYSTEM} maps to the groups listed for the
15490 @code{system-group} field of the @code{files-config} configuration,
15491 which is reified into the @code{cups-files.conf(5)} file. Other
15492 possible elements of the access list include specific user names, and
15493 @code{@@@var{group}} to indicate members of a specific group. The
15494 access list may also be simply @code{all} or @code{default}.
15496 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15499 @deftypevr {@code{policy-configuration} parameter} string job-private-values
15500 Specifies the list of job values to make private, or @code{all},
15501 @code{default}, or @code{none}.
15503 Defaults to @samp{"job-name job-originating-host-name
15504 job-originating-user-name phone"}.
15507 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
15508 Specifies an access list for a subscription's private values.
15509 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
15510 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15511 owner. @code{@@SYSTEM} maps to the groups listed for the
15512 @code{system-group} field of the @code{files-config} configuration,
15513 which is reified into the @code{cups-files.conf(5)} file. Other
15514 possible elements of the access list include specific user names, and
15515 @code{@@@var{group}} to indicate members of a specific group. The
15516 access list may also be simply @code{all} or @code{default}.
15518 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15521 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
15522 Specifies the list of job values to make private, or @code{all},
15523 @code{default}, or @code{none}.
15525 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
15526 notify-subscriber-user-name notify-user-data"}.
15529 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
15530 Access control by IPP operation.
15532 Defaults to @samp{()}.
15536 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
15537 Specifies whether job files (documents) are preserved after a job is
15538 printed. If a numeric value is specified, job files are preserved for
15539 the indicated number of seconds after printing. Otherwise a boolean
15540 value applies indefinitely.
15542 Defaults to @samp{86400}.
15545 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
15546 Specifies whether the job history is preserved after a job is printed.
15547 If a numeric value is specified, the job history is preserved for the
15548 indicated number of seconds after printing. If @code{#t}, the job
15549 history is preserved until the MaxJobs limit is reached.
15551 Defaults to @samp{#t}.
15554 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
15555 Specifies the amount of time to wait for job completion before
15556 restarting the scheduler.
15558 Defaults to @samp{30}.
15561 @deftypevr {@code{cups-configuration} parameter} string rip-cache
15562 Specifies the maximum amount of memory to use when converting documents
15563 into bitmaps for a printer.
15565 Defaults to @samp{"128m"}.
15568 @deftypevr {@code{cups-configuration} parameter} string server-admin
15569 Specifies the email address of the server administrator.
15571 Defaults to @samp{"root@@localhost.localdomain"}.
15574 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
15575 The ServerAlias directive is used for HTTP Host header validation when
15576 clients connect to the scheduler from external interfaces. Using the
15577 special name @code{*} can expose your system to known browser-based DNS
15578 rebinding attacks, even when accessing sites through a firewall. If the
15579 auto-discovery of alternate names does not work, we recommend listing
15580 each alternate name with a ServerAlias directive instead of using
15583 Defaults to @samp{*}.
15586 @deftypevr {@code{cups-configuration} parameter} string server-name
15587 Specifies the fully-qualified host name of the server.
15589 Defaults to @samp{"localhost"}.
15592 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
15593 Specifies what information is included in the Server header of HTTP
15594 responses. @code{None} disables the Server header. @code{ProductOnly}
15595 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
15596 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
15597 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
15598 the output of the @code{uname} command. @code{Full} reports @code{CUPS
15599 2.0.0 (@var{uname}) IPP/2.0}.
15601 Defaults to @samp{Minimal}.
15604 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
15605 Listens on the specified interfaces for encrypted connections. Valid
15606 values are of the form @var{address}:@var{port}, where @var{address} is
15607 either an IPv6 address enclosed in brackets, an IPv4 address, or
15608 @code{*} to indicate all addresses.
15610 Defaults to @samp{()}.
15613 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
15614 Sets encryption options. By default, CUPS only supports encryption
15615 using TLS v1.0 or higher using known secure cipher suites. Security is
15616 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
15617 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
15618 suites, which are required for some older clients. The @code{AllowSSL3} option
15619 enables SSL v3.0, which is required for some older clients that do not support
15620 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
15621 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
15622 protocol version to TLS v1.1.
15624 Defaults to @samp{()}.
15627 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
15628 Specifies whether the scheduler requires clients to strictly adhere to
15629 the IPP specifications.
15631 Defaults to @samp{#f}.
15634 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
15635 Specifies the HTTP request timeout, in seconds.
15637 Defaults to @samp{300}.
15641 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
15642 Specifies whether the web interface is enabled.
15644 Defaults to @samp{#f}.
15647 At this point you're probably thinking ``oh dear, Guix manual, I like
15648 you but you can stop already with the configuration options''. Indeed.
15649 However, one more point: it could be that you have an existing
15650 @code{cupsd.conf} that you want to use. In that case, you can pass an
15651 @code{opaque-cups-configuration} as the configuration of a
15652 @code{cups-service-type}.
15654 Available @code{opaque-cups-configuration} fields are:
15656 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
15660 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
15661 The contents of the @code{cupsd.conf}, as a string.
15664 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
15665 The contents of the @code{cups-files.conf} file, as a string.
15668 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
15669 strings of the same name, you could instantiate a CUPS service like
15673 (service cups-service-type
15674 (opaque-cups-configuration
15675 (cupsd.conf cupsd.conf)
15676 (cups-files.conf cups-files.conf)))
15680 @node Desktop Services
15681 @subsection Desktop Services
15683 The @code{(gnu services desktop)} module provides services that are
15684 usually useful in the context of a ``desktop'' setup---that is, on a
15685 machine running a graphical display server, possibly with graphical user
15686 interfaces, etc. It also defines services that provide specific desktop
15687 environments like GNOME, Xfce or MATE.
15689 To simplify things, the module defines a variable containing the set of
15690 services that users typically expect on a machine with a graphical
15691 environment and networking:
15693 @defvr {Scheme Variable} %desktop-services
15694 This is a list of services that builds upon @code{%base-services} and
15695 adds or adjusts services for a typical ``desktop'' setup.
15697 In particular, it adds a graphical login manager (@pxref{X Window,
15698 @code{gdm-service-type}}), screen lockers, a network management tool
15699 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
15700 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
15701 energy and color management services, the @code{elogind} login and seat
15702 manager, the Polkit privilege service, the GeoClue location service, the
15703 AccountsService daemon that allows authorized users change system passwords,
15704 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
15705 name service switch service configured to be able to use @code{nss-mdns}
15706 (@pxref{Name Service Switch, mDNS}).
15709 The @code{%desktop-services} variable can be used as the @code{services}
15710 field of an @code{operating-system} declaration (@pxref{operating-system
15711 Reference, @code{services}}).
15713 Additionally, the @code{gnome-desktop-service-type},
15714 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
15715 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
15716 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
15717 services like the backlight adjustment helpers and the power management
15718 utilities are added to the system, extending @code{polkit} and @code{dbus}
15719 appropriately, allowing GNOME to operate with elevated privileges on a
15720 limited number of special-purpose system interfaces. Additionally,
15721 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
15722 metapackage to the system profile. Likewise, adding the Xfce service
15723 not only adds the @code{xfce} metapackage to the system profile, but it
15724 also gives the Thunar file manager the ability to open a ``root-mode''
15725 file management window, if the user authenticates using the
15726 administrator's password via the standard polkit graphical interface.
15727 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
15728 appropriately, allowing MATE to operate with elevated privileges on a
15729 limited number of special-purpose system interfaces. Additionally,
15730 adding a service of type @code{mate-desktop-service-type} adds the MATE
15731 metapackage to the system profile. ``Adding Enlightenment'' means that
15732 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
15733 are set as setuid, allowing Enlightenment's screen locker and other
15734 functionality to work as expected.
15736 The desktop environments in Guix use the Xorg display server by
15737 default. If you'd like to use the newer display server protocol
15738 called Wayland, you need to use the @code{sddm-service} instead of
15739 GDM as the graphical login manager. You should then
15740 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
15741 also try starting GNOME on Wayland manually from a TTY with the
15742 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
15743 gnome-session``. Currently only GNOME has support for Wayland.
15745 @defvr {Scheme Variable} gnome-desktop-service-type
15746 This is the type of the service that adds the @uref{https://www.gnome.org,
15747 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
15748 object (see below.)
15750 This service adds the @code{gnome} package to the system profile, and extends
15751 polkit with the actions from @code{gnome-settings-daemon}.
15754 @deftp {Data Type} gnome-desktop-configuration
15755 Configuration record for the GNOME desktop environment.
15758 @item @code{gnome} (default: @code{gnome})
15759 The GNOME package to use.
15763 @defvr {Scheme Variable} xfce-desktop-service-type
15764 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
15765 desktop environment. Its value is an @code{xfce-desktop-configuration} object
15768 This service adds the @code{xfce} package to the system profile, and
15769 extends polkit with the ability for @code{thunar} to manipulate the file
15770 system as root from within a user session, after the user has authenticated
15771 with the administrator's password.
15774 @deftp {Data Type} xfce-desktop-configuration
15775 Configuration record for the Xfce desktop environment.
15778 @item @code{xfce} (default: @code{xfce})
15779 The Xfce package to use.
15783 @deffn {Scheme Variable} mate-desktop-service-type
15784 This is the type of the service that runs the @uref{https://mate-desktop.org/,
15785 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
15786 object (see below.)
15788 This service adds the @code{mate} package to the system
15789 profile, and extends polkit with the actions from
15790 @code{mate-settings-daemon}.
15793 @deftp {Data Type} mate-desktop-configuration
15794 Configuration record for the MATE desktop environment.
15797 @item @code{mate} (default: @code{mate})
15798 The MATE package to use.
15802 @deffn {Scheme Variable} enlightenment-desktop-service-type
15803 Return a service that adds the @code{enlightenment} package to the system
15804 profile, and extends dbus with actions from @code{efl}.
15807 @deftp {Data Type} enlightenment-desktop-service-configuration
15809 @item @code{enlightenment} (default: @code{enlightenment})
15810 The enlightenment package to use.
15814 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
15815 the default @code{%desktop-services} variable doesn't include any of
15816 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
15817 @code{%desktop-services} in the @code{services} field of your
15818 @code{operating-system}:
15821 (use-modules (gnu))
15822 (use-service-modules desktop)
15825 ;; cons* adds items to the list given as its last argument.
15826 (services (cons* (service gnome-desktop-service-type)
15827 (service xfce-desktop-service)
15828 %desktop-services))
15832 These desktop environments will then be available as options in the
15833 graphical login window.
15835 The actual service definitions included in @code{%desktop-services} and
15836 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
15837 are described below.
15839 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
15840 Return a service that runs the ``system bus'', using @var{dbus}, with
15841 support for @var{services}.
15843 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
15844 facility. Its system bus is used to allow system services to communicate
15845 and to be notified of system-wide events.
15847 @var{services} must be a list of packages that provide an
15848 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
15849 and policy files. For example, to allow avahi-daemon to use the system bus,
15850 @var{services} must be equal to @code{(list avahi)}.
15853 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
15854 Return a service that runs the @code{elogind} login and
15855 seat management daemon. @uref{https://github.com/elogind/elogind,
15856 Elogind} exposes a D-Bus interface that can be used to know which users
15857 are logged in, know what kind of sessions they have open, suspend the
15858 system, inhibit system suspend, reboot the system, and other tasks.
15860 Elogind handles most system-level power events for a computer, for
15861 example suspending the system when a lid is closed, or shutting it down
15862 when the power button is pressed.
15864 The @var{config} keyword argument specifies the configuration for
15865 elogind, and should be the result of an @code{(elogind-configuration
15866 (@var{parameter} @var{value})...)} invocation. Available parameters and
15867 their default values are:
15870 @item kill-user-processes?
15872 @item kill-only-users
15874 @item kill-exclude-users
15876 @item inhibit-delay-max-seconds
15878 @item handle-power-key
15880 @item handle-suspend-key
15882 @item handle-hibernate-key
15884 @item handle-lid-switch
15886 @item handle-lid-switch-docked
15888 @item power-key-ignore-inhibited?
15890 @item suspend-key-ignore-inhibited?
15892 @item hibernate-key-ignore-inhibited?
15894 @item lid-switch-ignore-inhibited?
15896 @item holdoff-timeout-seconds
15900 @item idle-action-seconds
15902 @item runtime-directory-size-percent
15904 @item runtime-directory-size
15908 @item suspend-state
15909 @code{("mem" "standby" "freeze")}
15912 @item hibernate-state
15914 @item hibernate-mode
15915 @code{("platform" "shutdown")}
15916 @item hybrid-sleep-state
15918 @item hybrid-sleep-mode
15919 @code{("suspend" "platform" "shutdown")}
15923 @deffn {Scheme Procedure} accountsservice-service @
15924 [#:accountsservice @var{accountsservice}]
15925 Return a service that runs AccountsService, a system service that can
15926 list available accounts, change their passwords, and so on.
15927 AccountsService integrates with PolicyKit to enable unprivileged users
15928 to acquire the capability to modify their system configuration.
15929 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
15930 accountsservice web site} for more information.
15932 The @var{accountsservice} keyword argument is the @code{accountsservice}
15933 package to expose as a service.
15936 @deffn {Scheme Procedure} polkit-service @
15937 [#:polkit @var{polkit}]
15938 Return a service that runs the
15939 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
15940 management service}, which allows system administrators to grant access to
15941 privileged operations in a structured way. By querying the Polkit service, a
15942 privileged system component can know when it should grant additional
15943 capabilities to ordinary users. For example, an ordinary user can be granted
15944 the capability to suspend the system if the user is logged in locally.
15947 @defvr {Scheme Variable} polkit-wheel-service
15948 Service that adds the @code{wheel} group as admins to the Polkit
15949 service. This makes it so that users in the @code{wheel} group are queried
15950 for their own passwords when performing administrative actions instead of
15951 @code{root}'s, similar to the behaviour used by @code{sudo}.
15954 @defvr {Scheme Variable} upower-service-type
15955 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
15956 system-wide monitor for power consumption and battery levels, with the given
15957 configuration settings.
15959 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
15960 notably used by GNOME.
15963 @deftp {Data Type} upower-configuration
15964 Data type representation the configuration for UPower.
15968 @item @code{upower} (default: @var{upower})
15969 Package to use for @code{upower}.
15971 @item @code{watts-up-pro?} (default: @code{#f})
15972 Enable the Watts Up Pro device.
15974 @item @code{poll-batteries?} (default: @code{#t})
15975 Enable polling the kernel for battery level changes.
15977 @item @code{ignore-lid?} (default: @code{#f})
15978 Ignore the lid state, this can be useful if it's incorrect on a device.
15980 @item @code{use-percentage-for-policy?} (default: @code{#f})
15981 Whether battery percentage based policy should be used. The default is to use
15982 the time left, change to @code{#t} to use the percentage.
15984 @item @code{percentage-low} (default: @code{10})
15985 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15986 at which the battery is considered low.
15988 @item @code{percentage-critical} (default: @code{3})
15989 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15990 at which the battery is considered critical.
15992 @item @code{percentage-action} (default: @code{2})
15993 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15994 at which action will be taken.
15996 @item @code{time-low} (default: @code{1200})
15997 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15998 seconds at which the battery is considered low.
16000 @item @code{time-critical} (default: @code{300})
16001 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16002 seconds at which the battery is considered critical.
16004 @item @code{time-action} (default: @code{120})
16005 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
16006 seconds at which action will be taken.
16008 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
16009 The action taken when @code{percentage-action} or @code{time-action} is
16010 reached (depending on the configuration of @code{use-percentage-for-policy?}).
16012 Possible values are:
16022 @code{'hybrid-sleep}.
16028 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
16029 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
16030 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
16031 notifications and ways to mount/unmount disks. Programs that talk to UDisks
16032 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
16035 @deffn {Scheme Variable} colord-service-type
16036 This is the type of the service that runs @command{colord}, a system
16037 service with a D-Bus
16038 interface to manage the color profiles of input and output devices such as
16039 screens and scanners. It is notably used by the GNOME Color Manager graphical
16040 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
16041 site} for more information.
16044 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
16045 Return a configuration allowing an application to access GeoClue
16046 location data. @var{name} is the Desktop ID of the application, without
16047 the @code{.desktop} part. If @var{allowed?} is true, the application
16048 will have access to location information by default. The boolean
16049 @var{system?} value indicates whether an application is a system component
16050 or not. Finally @var{users} is a list of UIDs of all users for which
16051 this application is allowed location info access. An empty users list
16052 means that all users are allowed.
16055 @cindex scanner access
16056 @deffn {Scheme Procedure} sane-service-type
16057 This service provides access to scanners @i{via}
16058 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
16062 @defvr {Scheme Variable} %standard-geoclue-applications
16063 The standard list of well-known GeoClue application configurations,
16064 granting authority to the GNOME date-and-time utility to ask for the
16065 current location in order to set the time zone, and allowing the
16066 IceCat and Epiphany web browsers to request location information.
16067 IceCat and Epiphany both query the user before allowing a web page to
16068 know the user's location.
16071 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
16072 [#:whitelist '()] @
16073 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
16074 [#:submit-data? #f]
16075 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
16076 [#:submission-nick "geoclue"] @
16077 [#:applications %standard-geoclue-applications]
16078 Return a service that runs the GeoClue location service. This service
16079 provides a D-Bus interface to allow applications to request access to a
16080 user's physical location, and optionally to add information to online
16081 location databases. See
16082 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
16083 web site} for more information.
16086 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
16087 [@w{#:auto-enable? #f}]
16088 Return a service that runs the @command{bluetoothd} daemon, which
16089 manages all the Bluetooth devices and provides a number of D-Bus
16090 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
16091 powered automatically at boot, which can be useful when using a
16092 bluetooth keyboard or mouse.
16094 Users need to be in the @code{lp} group to access the D-Bus service.
16097 @defvr {Scheme Variable} gnome-keyring-service-type
16098 This is the type of the service that adds the
16099 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
16100 value is a @code{gnome-keyring-configuration} object (see below.)
16102 This service adds the @code{gnome-keyring} package to the system profile
16103 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
16104 a user's login keyring when they log in or setting its password with passwd.
16107 @deftp {Data Type} gnome-keyring-configuration
16108 Configuration record for the GNOME Keyring service.
16111 @item @code{keyring} (default: @code{gnome-keyring})
16112 The GNOME keyring package to use.
16114 @item @code{pam-services}
16115 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
16116 services to extend, where @var{service} is the name of an existing
16117 service to extend and @var{kind} is one of @code{login} or
16120 If @code{login} is given, it adds an optional
16121 @code{pam_gnome_keyring.so} to the auth block without arguments and to
16122 the session block with @code{auto_start}. If @code{passwd} is given, it
16123 adds an optional @code{pam_gnome_keyring.so} to the password block
16126 By default, this field contains ``gdm-password'' with the value @code{login}
16127 and ``passwd'' is with the value @code{passwd}.
16132 @node Sound Services
16133 @subsection Sound Services
16135 @cindex sound support
16137 @cindex PulseAudio, sound support
16139 The @code{(gnu services sound)} module provides a service to configure the
16140 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
16141 preferred ALSA output driver.
16143 @deffn {Scheme Variable} alsa-service-type
16144 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
16145 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
16146 configuration file. The value for this type is a @command{alsa-configuration}
16147 record as in this example:
16150 (service alsa-service-type)
16153 See below for details about @code{alsa-configuration}.
16156 @deftp {Data Type} alsa-configuration
16157 Data type representing the configuration for @code{alsa-service}.
16160 @item @code{alsa-plugins} (default: @var{alsa-plugins})
16161 @code{alsa-plugins} package to use.
16163 @item @code{pulseaudio?} (default: @var{#t})
16164 Whether ALSA applications should transparently be made to use the
16165 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
16167 Using PulseAudio allows you to run several sound-producing applications
16168 at the same time and to individual control them @i{via}
16169 @command{pavucontrol}, among other things.
16171 @item @code{extra-options} (default: @var{""})
16172 String to append to the @file{/etc/asound.conf} file.
16177 Individual users who want to override the system configuration of ALSA can do
16178 it with the @file{~/.asoundrc} file:
16181 # In guix, we have to specify the absolute path for plugins.
16183 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
16186 # Routing ALSA to jack:
16187 # <http://jackaudio.org/faq/routing_alsa.html>.
16191 0 system:playback_1
16192 1 system:playback_2
16209 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
16212 @deffn {Scheme Variable} pulseaudio-service-type
16213 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
16214 sound server. It exists to allow system overrides of the default settings
16215 via @code{pulseaudio-configuration}, see below.
16218 This service on its own does not ensure, that the @code{pulseaudio} package
16219 exists on your machine. It merely adds configuration files for it, as
16220 detailed below. In the (admittedly unlikely) case, that you find yourself
16221 without a @code{pulseaudio} package, consider enabling it through the
16222 @code{alsa-service-type} above.
16226 @deftp {Data Type} pulseaudio-configuration
16227 Data type representing the configuration for @code{pulseaudio-service}.
16230 @item @var{client-conf} (default: @code{'()})
16231 List of settings to set in @file{client.conf}.
16232 Accepts a list of strings or a symbol-value pairs. A string will be
16233 inserted as-is with a newline added. A pair will be formatted as
16234 ``key = value'', again with a newline added.
16236 @item @var{daemon-conf} (default: @code{'((flat-volumes . no))})
16237 List of settings to set in @file{daemon.conf}, formatted just like
16240 @item @var{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
16241 Script file to use as as @file{default.pa}.
16243 @item @var{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
16244 Script file to use as as @file{system.pa}.
16248 @deffn {Scheme Variable} ladspa-service-type
16249 This service sets the @var{LADSPA_PATH} variable, so that programs, which
16250 respect it, e.g. PulseAudio, can load LADSPA plugins.
16252 The following example will setup the service to enable modules from the
16253 @code{swh-plugins} package:
16256 (service ladspa-service-type
16257 (ladspa-configuration (plugins (list swh-plugins))))
16260 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
16265 @node Database Services
16266 @subsection Database Services
16270 The @code{(gnu services databases)} module provides the following services.
16272 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
16273 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
16274 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
16275 Return a service that runs @var{postgresql}, the PostgreSQL database
16278 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
16279 creates a database cluster with @var{locale} as the default
16280 locale, stored in @var{data-directory}. It then listens on @var{port}.
16282 @cindex postgresql extension-packages
16283 Additional extensions are loaded from packages listed in
16284 @var{extension-packages}. Extensions are available at runtime. For instance,
16285 to create a geographic database using the @code{postgis} extension, a user can
16286 configure the postgresql-service as in this example:
16290 (use-package-modules databases geo)
16294 ;; postgresql is required to run `psql' but postgis is not required for
16295 ;; proper operation.
16296 (packages (cons* postgresql %base-packages))
16299 (postgresql-service #:extension-packages (list postgis))
16303 Then the extension becomes visible and you can initialise an empty geographic
16304 database in this way:
16308 > create database postgistest;
16309 > \connect postgistest;
16310 > create extension postgis;
16311 > create extension postgis_topology;
16314 There is no need to add this field for contrib extensions such as hstore or
16315 dblink as they are already loadable by postgresql. This field is only
16316 required to add extensions provided by other packages.
16319 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
16320 Return a service that runs @command{mysqld}, the MySQL or MariaDB
16323 The optional @var{config} argument specifies the configuration for
16324 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
16327 @deftp {Data Type} mysql-configuration
16328 Data type representing the configuration of @var{mysql-service}.
16331 @item @code{mysql} (default: @var{mariadb})
16332 Package object of the MySQL database server, can be either @var{mariadb}
16335 For MySQL, a temporary root password will be displayed at activation time.
16336 For MariaDB, the root password is empty.
16338 @item @code{port} (default: @code{3306})
16339 TCP port on which the database server listens for incoming connections.
16343 @defvr {Scheme Variable} memcached-service-type
16344 This is the service type for the @uref{https://memcached.org/,
16345 Memcached} service, which provides a distributed in memory cache. The
16346 value for the service type is a @code{memcached-configuration} object.
16350 (service memcached-service-type)
16353 @deftp {Data Type} memcached-configuration
16354 Data type representing the configuration of memcached.
16357 @item @code{memcached} (default: @code{memcached})
16358 The Memcached package to use.
16360 @item @code{interfaces} (default: @code{'("0.0.0.0")})
16361 Network interfaces on which to listen.
16363 @item @code{tcp-port} (default: @code{11211})
16364 Port on which to accept connections on,
16366 @item @code{udp-port} (default: @code{11211})
16367 Port on which to accept UDP connections on, a value of 0 will disable
16368 listening on a UDP socket.
16370 @item @code{additional-options} (default: @code{'()})
16371 Additional command line options to pass to @code{memcached}.
16375 @defvr {Scheme Variable} mongodb-service-type
16376 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
16377 The value for the service type is a @code{mongodb-configuration} object.
16381 (service mongodb-service-type)
16384 @deftp {Data Type} mongodb-configuration
16385 Data type representing the configuration of mongodb.
16388 @item @code{mongodb} (default: @code{mongodb})
16389 The MongoDB package to use.
16391 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
16392 The configuration file for MongoDB.
16394 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
16395 This value is used to create the directory, so that it exists and is
16396 owned by the mongodb user. It should match the data-directory which
16397 MongoDB is configured to use through the configuration file.
16401 @defvr {Scheme Variable} redis-service-type
16402 This is the service type for the @uref{https://redis.io/, Redis}
16403 key/value store, whose value is a @code{redis-configuration} object.
16406 @deftp {Data Type} redis-configuration
16407 Data type representing the configuration of redis.
16410 @item @code{redis} (default: @code{redis})
16411 The Redis package to use.
16413 @item @code{bind} (default: @code{"127.0.0.1"})
16414 Network interface on which to listen.
16416 @item @code{port} (default: @code{6379})
16417 Port on which to accept connections on, a value of 0 will disable
16418 listening on a TCP socket.
16420 @item @code{working-directory} (default: @code{"/var/lib/redis"})
16421 Directory in which to store the database and related files.
16425 @node Mail Services
16426 @subsection Mail Services
16430 The @code{(gnu services mail)} module provides Guix service definitions
16431 for email services: IMAP, POP3, and LMTP servers, as well as mail
16432 transport agents (MTAs). Lots of acronyms! These services are detailed
16433 in the subsections below.
16435 @subsubheading Dovecot Service
16437 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
16438 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
16441 By default, Dovecot does not need much configuration; the default
16442 configuration object created by @code{(dovecot-configuration)} will
16443 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
16444 certificate will be generated for TLS-protected connections, though
16445 Dovecot will also listen on cleartext ports by default. There are a
16446 number of options, though, which mail administrators might need to change,
16447 and as is the case with other services, Guix allows the system
16448 administrator to specify these parameters via a uniform Scheme interface.
16450 For example, to specify that mail is located at @code{maildir~/.mail},
16451 one would instantiate the Dovecot service like this:
16454 (dovecot-service #:config
16455 (dovecot-configuration
16456 (mail-location "maildir:~/.mail")))
16459 The available configuration parameters follow. Each parameter
16460 definition is preceded by its type; for example, @samp{string-list foo}
16461 indicates that the @code{foo} parameter should be specified as a list of
16462 strings. There is also a way to specify the configuration as a string,
16463 if you have an old @code{dovecot.conf} file that you want to port over
16464 from some other system; see the end for more details.
16466 @c The following documentation was initially generated by
16467 @c (generate-documentation) in (gnu services mail). Manually maintained
16468 @c documentation is better, so we shouldn't hesitate to edit below as
16469 @c needed. However if the change you want to make to this documentation
16470 @c can be done in an automated way, it's probably easier to change
16471 @c (generate-documentation) than to make it below and have to deal with
16472 @c the churn as dovecot updates.
16474 Available @code{dovecot-configuration} fields are:
16476 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
16477 The dovecot package.
16480 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
16481 A list of IPs or hosts where to listen for connections. @samp{*}
16482 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
16483 interfaces. If you want to specify non-default ports or anything more
16484 complex, customize the address and port fields of the
16485 @samp{inet-listener} of the specific services you are interested in.
16488 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
16489 List of protocols we want to serve. Available protocols include
16490 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
16492 Available @code{protocol-configuration} fields are:
16494 @deftypevr {@code{protocol-configuration} parameter} string name
16495 The name of the protocol.
16498 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
16499 UNIX socket path to the master authentication server to find users.
16500 This is used by imap (for shared users) and lda.
16501 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16504 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
16505 Space separated list of plugins to load.
16508 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
16509 Maximum number of IMAP connections allowed for a user from each IP
16510 address. NOTE: The username is compared case-sensitively.
16511 Defaults to @samp{10}.
16516 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
16517 List of services to enable. Available services include @samp{imap},
16518 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
16521 Available @code{service-configuration} fields are:
16523 @deftypevr {@code{service-configuration} parameter} string kind
16524 The service kind. Valid values include @code{director},
16525 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
16526 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
16527 @code{tcpwrap}, @code{quota-warning}, or anything else.
16530 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
16531 Listeners for the service. A listener is either a
16532 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
16533 an @code{inet-listener-configuration}.
16534 Defaults to @samp{()}.
16536 Available @code{unix-listener-configuration} fields are:
16538 @deftypevr {@code{unix-listener-configuration} parameter} string path
16539 Path to the file, relative to @code{base-dir} field. This is also used as
16543 @deftypevr {@code{unix-listener-configuration} parameter} string mode
16544 The access mode for the socket.
16545 Defaults to @samp{"0600"}.
16548 @deftypevr {@code{unix-listener-configuration} parameter} string user
16549 The user to own the socket.
16550 Defaults to @samp{""}.
16553 @deftypevr {@code{unix-listener-configuration} parameter} string group
16554 The group to own the socket.
16555 Defaults to @samp{""}.
16559 Available @code{fifo-listener-configuration} fields are:
16561 @deftypevr {@code{fifo-listener-configuration} parameter} string path
16562 Path to the file, relative to @code{base-dir} field. This is also used as
16566 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
16567 The access mode for the socket.
16568 Defaults to @samp{"0600"}.
16571 @deftypevr {@code{fifo-listener-configuration} parameter} string user
16572 The user to own the socket.
16573 Defaults to @samp{""}.
16576 @deftypevr {@code{fifo-listener-configuration} parameter} string group
16577 The group to own the socket.
16578 Defaults to @samp{""}.
16582 Available @code{inet-listener-configuration} fields are:
16584 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
16585 The protocol to listen for.
16588 @deftypevr {@code{inet-listener-configuration} parameter} string address
16589 The address on which to listen, or empty for all addresses.
16590 Defaults to @samp{""}.
16593 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
16594 The port on which to listen.
16597 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
16598 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
16600 Defaults to @samp{#t}.
16605 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
16606 Maximum number of simultaneous client connections per process. Once
16607 this number of connections is received, the next incoming connection
16608 will prompt Dovecot to spawn another process. If set to 0,
16609 @code{default-client-limit} is used instead.
16611 Defaults to @samp{0}.
16615 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
16616 Number of connections to handle before starting a new process.
16617 Typically the only useful values are 0 (unlimited) or 1. 1 is more
16618 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
16619 Defaults to @samp{1}.
16623 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
16624 Maximum number of processes that can exist for this service. If set to
16625 0, @code{default-process-limit} is used instead.
16627 Defaults to @samp{0}.
16631 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
16632 Number of processes to always keep waiting for more connections.
16633 Defaults to @samp{0}.
16636 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
16637 If you set @samp{service-count 0}, you probably need to grow
16639 Defaults to @samp{256000000}.
16644 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
16645 Dict configuration, as created by the @code{dict-configuration}
16648 Available @code{dict-configuration} fields are:
16650 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
16651 A list of key-value pairs that this dict should hold.
16652 Defaults to @samp{()}.
16657 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
16658 A list of passdb configurations, each one created by the
16659 @code{passdb-configuration} constructor.
16661 Available @code{passdb-configuration} fields are:
16663 @deftypevr {@code{passdb-configuration} parameter} string driver
16664 The driver that the passdb should use. Valid values include
16665 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
16667 Defaults to @samp{"pam"}.
16670 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
16671 Space separated list of arguments to the passdb driver.
16672 Defaults to @samp{""}.
16677 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
16678 List of userdb configurations, each one created by the
16679 @code{userdb-configuration} constructor.
16681 Available @code{userdb-configuration} fields are:
16683 @deftypevr {@code{userdb-configuration} parameter} string driver
16684 The driver that the userdb should use. Valid values include
16685 @samp{passwd} and @samp{static}.
16686 Defaults to @samp{"passwd"}.
16689 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
16690 Space separated list of arguments to the userdb driver.
16691 Defaults to @samp{""}.
16694 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
16695 Override fields from passwd.
16696 Defaults to @samp{()}.
16701 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
16702 Plug-in configuration, created by the @code{plugin-configuration}
16706 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
16707 List of namespaces. Each item in the list is created by the
16708 @code{namespace-configuration} constructor.
16710 Available @code{namespace-configuration} fields are:
16712 @deftypevr {@code{namespace-configuration} parameter} string name
16713 Name for this namespace.
16716 @deftypevr {@code{namespace-configuration} parameter} string type
16717 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
16718 Defaults to @samp{"private"}.
16721 @deftypevr {@code{namespace-configuration} parameter} string separator
16722 Hierarchy separator to use. You should use the same separator for
16723 all namespaces or some clients get confused. @samp{/} is usually a good
16724 one. The default however depends on the underlying mail storage
16726 Defaults to @samp{""}.
16729 @deftypevr {@code{namespace-configuration} parameter} string prefix
16730 Prefix required to access this namespace. This needs to be
16731 different for all namespaces. For example @samp{Public/}.
16732 Defaults to @samp{""}.
16735 @deftypevr {@code{namespace-configuration} parameter} string location
16736 Physical location of the mailbox. This is in the same format as
16737 mail_location, which is also the default for it.
16738 Defaults to @samp{""}.
16741 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
16742 There can be only one INBOX, and this setting defines which
16744 Defaults to @samp{#f}.
16747 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
16748 If namespace is hidden, it's not advertised to clients via NAMESPACE
16749 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
16750 useful when converting from another server with different namespaces
16751 which you want to deprecate but still keep working. For example you can
16752 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
16754 Defaults to @samp{#f}.
16757 @deftypevr {@code{namespace-configuration} parameter} boolean list?
16758 Show the mailboxes under this namespace with the LIST command. This
16759 makes the namespace visible for clients that do not support the NAMESPACE
16760 extension. The special @code{children} value lists child mailboxes, but
16761 hides the namespace prefix.
16762 Defaults to @samp{#t}.
16765 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
16766 Namespace handles its own subscriptions. If set to @code{#f}, the
16767 parent namespace handles them. The empty prefix should always have this
16769 Defaults to @samp{#t}.
16772 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
16773 List of predefined mailboxes in this namespace.
16774 Defaults to @samp{()}.
16776 Available @code{mailbox-configuration} fields are:
16778 @deftypevr {@code{mailbox-configuration} parameter} string name
16779 Name for this mailbox.
16782 @deftypevr {@code{mailbox-configuration} parameter} string auto
16783 @samp{create} will automatically create this mailbox.
16784 @samp{subscribe} will both create and subscribe to the mailbox.
16785 Defaults to @samp{"no"}.
16788 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
16789 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
16790 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
16791 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
16792 Defaults to @samp{()}.
16799 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
16800 Base directory where to store runtime data.
16801 Defaults to @samp{"/var/run/dovecot/"}.
16804 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
16805 Greeting message for clients.
16806 Defaults to @samp{"Dovecot ready."}.
16809 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
16810 List of trusted network ranges. Connections from these IPs are
16811 allowed to override their IP addresses and ports (for logging and for
16812 authentication checks). @samp{disable-plaintext-auth} is also ignored
16813 for these networks. Typically you would specify your IMAP proxy servers
16815 Defaults to @samp{()}.
16818 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
16819 List of login access check sockets (e.g.@: tcpwrap).
16820 Defaults to @samp{()}.
16823 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
16824 Show more verbose process titles (in ps). Currently shows user name
16825 and IP address. Useful for seeing who is actually using the IMAP
16826 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
16828 Defaults to @samp{#f}.
16831 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
16832 Should all processes be killed when Dovecot master process shuts down.
16833 Setting this to @code{#f} means that Dovecot can be upgraded without
16834 forcing existing client connections to close (although that could also
16835 be a problem if the upgrade is e.g.@: due to a security fix).
16836 Defaults to @samp{#t}.
16839 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
16840 If non-zero, run mail commands via this many connections to doveadm
16841 server, instead of running them directly in the same process.
16842 Defaults to @samp{0}.
16845 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
16846 UNIX socket or host:port used for connecting to doveadm server.
16847 Defaults to @samp{"doveadm-server"}.
16850 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
16851 List of environment variables that are preserved on Dovecot startup
16852 and passed down to all of its child processes. You can also give
16853 key=value pairs to always set specific settings.
16856 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
16857 Disable LOGIN command and all other plaintext authentications unless
16858 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
16859 matches the local IP (i.e.@: you're connecting from the same computer),
16860 the connection is considered secure and plaintext authentication is
16861 allowed. See also ssl=required setting.
16862 Defaults to @samp{#t}.
16865 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
16866 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
16867 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
16868 for caching to be used.
16869 Defaults to @samp{0}.
16872 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
16873 Time to live for cached data. After TTL expires the cached record
16874 is no longer used, *except* if the main database lookup returns internal
16875 failure. We also try to handle password changes automatically: If
16876 user's previous authentication was successful, but this one wasn't, the
16877 cache isn't used. For now this works only with plaintext
16879 Defaults to @samp{"1 hour"}.
16882 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
16883 TTL for negative hits (user not found, password mismatch).
16884 0 disables caching them completely.
16885 Defaults to @samp{"1 hour"}.
16888 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
16889 List of realms for SASL authentication mechanisms that need them.
16890 You can leave it empty if you don't want to support multiple realms.
16891 Many clients simply use the first one listed here, so keep the default
16893 Defaults to @samp{()}.
16896 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
16897 Default realm/domain to use if none was specified. This is used for
16898 both SASL realms and appending @@domain to username in plaintext
16900 Defaults to @samp{""}.
16903 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
16904 List of allowed characters in username. If the user-given username
16905 contains a character not listed in here, the login automatically fails.
16906 This is just an extra check to make sure user can't exploit any
16907 potential quote escaping vulnerabilities with SQL/LDAP databases. If
16908 you want to allow all characters, set this value to empty.
16909 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
16912 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
16913 Username character translations before it's looked up from
16914 databases. The value contains series of from -> to characters. For
16915 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
16916 translated to @samp{@@}.
16917 Defaults to @samp{""}.
16920 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
16921 Username formatting before it's looked up from databases. You can
16922 use the standard variables here, e.g.@: %Lu would lowercase the username,
16923 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
16924 change the @samp{@@} into @samp{-AT-}. This translation is done after
16925 @samp{auth-username-translation} changes.
16926 Defaults to @samp{"%Lu"}.
16929 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
16930 If you want to allow master users to log in by specifying the master
16931 username within the normal username string (i.e.@: not using SASL
16932 mechanism's support for it), you can specify the separator character
16933 here. The format is then <username><separator><master username>.
16934 UW-IMAP uses @samp{*} as the separator, so that could be a good
16936 Defaults to @samp{""}.
16939 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
16940 Username to use for users logging in with ANONYMOUS SASL
16942 Defaults to @samp{"anonymous"}.
16945 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
16946 Maximum number of dovecot-auth worker processes. They're used to
16947 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
16948 They're automatically created and destroyed as needed.
16949 Defaults to @samp{30}.
16952 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
16953 Host name to use in GSSAPI principal names. The default is to use
16954 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
16955 allow all keytab entries.
16956 Defaults to @samp{""}.
16959 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
16960 Kerberos keytab to use for the GSSAPI mechanism. Will use the
16961 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
16962 need to change the auth service to run as root to be able to read this
16964 Defaults to @samp{""}.
16967 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
16968 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
16969 and @samp{ntlm-auth} helper.
16970 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
16971 Defaults to @samp{#f}.
16974 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
16975 Path for Samba's @samp{ntlm-auth} helper binary.
16976 Defaults to @samp{"/usr/bin/ntlm_auth"}.
16979 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
16980 Time to delay before replying to failed authentications.
16981 Defaults to @samp{"2 secs"}.
16984 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
16985 Require a valid SSL client certificate or the authentication
16987 Defaults to @samp{#f}.
16990 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
16991 Take the username from client's SSL certificate, using
16992 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
16994 Defaults to @samp{#f}.
16997 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
16998 List of wanted authentication mechanisms. Supported mechanisms are:
16999 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
17000 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
17001 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
17002 @samp{disable-plaintext-auth} setting.
17005 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
17006 List of IPs or hostnames to all director servers, including ourself.
17007 Ports can be specified as ip:port. The default port is the same as what
17008 director service's @samp{inet-listener} is using.
17009 Defaults to @samp{()}.
17012 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
17013 List of IPs or hostnames to all backend mail servers. Ranges are
17014 allowed too, like 10.0.0.10-10.0.0.30.
17015 Defaults to @samp{()}.
17018 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
17019 How long to redirect users to a specific server after it no longer
17020 has any connections.
17021 Defaults to @samp{"15 min"}.
17024 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
17025 How the username is translated before being hashed. Useful values
17026 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
17027 are shared within domain.
17028 Defaults to @samp{"%Lu"}.
17031 @deftypevr {@code{dovecot-configuration} parameter} string log-path
17032 Log file to use for error messages. @samp{syslog} logs to syslog,
17033 @samp{/dev/stderr} logs to stderr.
17034 Defaults to @samp{"syslog"}.
17037 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
17038 Log file to use for informational messages. Defaults to
17040 Defaults to @samp{""}.
17043 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
17044 Log file to use for debug messages. Defaults to
17045 @samp{info-log-path}.
17046 Defaults to @samp{""}.
17049 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
17050 Syslog facility to use if you're logging to syslog. Usually if you
17051 don't want to use @samp{mail}, you'll use local0..local7. Also other
17052 standard facilities are supported.
17053 Defaults to @samp{"mail"}.
17056 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
17057 Log unsuccessful authentication attempts and the reasons why they
17059 Defaults to @samp{#f}.
17062 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
17063 In case of password mismatches, log the attempted password. Valid
17064 values are no, plain and sha1. sha1 can be useful for detecting brute
17065 force password attempts vs. user simply trying the same password over
17066 and over again. You can also truncate the value to n chars by appending
17067 ":n" (e.g.@: sha1:6).
17068 Defaults to @samp{"no"}.
17071 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
17072 Even more verbose logging for debugging purposes. Shows for example
17074 Defaults to @samp{#f}.
17077 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
17078 In case of password mismatches, log the passwords and used scheme so
17079 the problem can be debugged. Enabling this also enables
17081 Defaults to @samp{#f}.
17084 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
17085 Enable mail process debugging. This can help you figure out why
17086 Dovecot isn't finding your mails.
17087 Defaults to @samp{#f}.
17090 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
17091 Show protocol level SSL errors.
17092 Defaults to @samp{#f}.
17095 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
17096 Prefix for each line written to log file. % codes are in
17097 strftime(3) format.
17098 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
17101 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
17102 List of elements we want to log. The elements which have a
17103 non-empty variable value are joined together to form a comma-separated
17107 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
17108 Login log format. %s contains @samp{login-log-format-elements}
17109 string, %$ contains the data we want to log.
17110 Defaults to @samp{"%$: %s"}.
17113 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
17114 Log prefix for mail processes. See doc/wiki/Variables.txt for list
17115 of possible variables you can use.
17116 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
17119 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
17120 Format to use for logging mail deliveries. You can use variables:
17123 Delivery status message (e.g.@: @samp{saved to INBOX})
17135 Defaults to @samp{"msgid=%m: %$"}.
17138 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
17139 Location for users' mailboxes. The default is empty, which means
17140 that Dovecot tries to find the mailboxes automatically. This won't work
17141 if the user doesn't yet have any mail, so you should explicitly tell
17142 Dovecot the full location.
17144 If you're using mbox, giving a path to the INBOX
17145 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
17146 where the other mailboxes are kept. This is called the "root mail
17147 directory", and it must be the first path given in the
17148 @samp{mail-location} setting.
17150 There are a few special variables you can use, eg.:
17156 user part in user@@domain, same as %u if there's no domain
17158 domain part in user@@domain, empty if there's no domain
17163 See doc/wiki/Variables.txt for full list. Some examples:
17165 @item maildir:~/Maildir
17166 @item mbox:~/mail:INBOX=/var/mail/%u
17167 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
17169 Defaults to @samp{""}.
17172 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
17173 System user and group used to access mails. If you use multiple,
17174 userdb can override these by returning uid or gid fields. You can use
17175 either numbers or names. <doc/wiki/UserIds.txt>.
17176 Defaults to @samp{""}.
17179 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
17181 Defaults to @samp{""}.
17184 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
17185 Group to enable temporarily for privileged operations. Currently
17186 this is used only with INBOX when either its initial creation or
17187 dotlocking fails. Typically this is set to "mail" to give access to
17189 Defaults to @samp{""}.
17192 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
17193 Grant access to these supplementary groups for mail processes.
17194 Typically these are used to set up access to shared mailboxes. Note
17195 that it may be dangerous to set these if users can create
17196 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
17197 could allow a user to delete others' mailboxes, or ln -s
17198 /secret/shared/box ~/mail/mybox would allow reading it).
17199 Defaults to @samp{""}.
17202 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
17203 Allow full file system access to clients. There's no access checks
17204 other than what the operating system does for the active UID/GID. It
17205 works with both maildir and mboxes, allowing you to prefix mailboxes
17206 names with e.g.@: /path/ or ~user/.
17207 Defaults to @samp{#f}.
17210 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
17211 Don't use mmap() at all. This is required if you store indexes to
17212 shared file systems (NFS or clustered file system).
17213 Defaults to @samp{#f}.
17216 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
17217 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
17218 supports @samp{O_EXCL} since version 3, so this should be safe to use
17219 nowadays by default.
17220 Defaults to @samp{#t}.
17223 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
17224 When to use fsync() or fdatasync() calls:
17227 Whenever necessary to avoid losing important data
17229 Useful with e.g.@: NFS when write()s are delayed
17231 Never use it (best performance, but crashes can lose data).
17233 Defaults to @samp{"optimized"}.
17236 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
17237 Mail storage exists in NFS. Set this to yes to make Dovecot flush
17238 NFS caches whenever needed. If you're using only a single mail server
17240 Defaults to @samp{#f}.
17243 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
17244 Mail index files also exist in NFS. Setting this to yes requires
17245 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
17246 Defaults to @samp{#f}.
17249 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
17250 Locking method for index files. Alternatives are fcntl, flock and
17251 dotlock. Dotlocking uses some tricks which may create more disk I/O
17252 than other locking methods. NFS users: flock doesn't work, remember to
17253 change @samp{mmap-disable}.
17254 Defaults to @samp{"fcntl"}.
17257 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
17258 Directory in which LDA/LMTP temporarily stores incoming mails >128
17260 Defaults to @samp{"/tmp"}.
17263 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
17264 Valid UID range for users. This is mostly to make sure that users can't
17265 log in as daemons or other system users. Note that denying root logins is
17266 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
17268 Defaults to @samp{500}.
17271 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
17273 Defaults to @samp{0}.
17276 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
17277 Valid GID range for users. Users having non-valid GID as primary group ID
17278 aren't allowed to log in. If user belongs to supplementary groups with
17279 non-valid GIDs, those groups are not set.
17280 Defaults to @samp{1}.
17283 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
17285 Defaults to @samp{0}.
17288 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
17289 Maximum allowed length for mail keyword name. It's only forced when
17290 trying to create new keywords.
17291 Defaults to @samp{50}.
17294 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
17295 List of directories under which chrooting is allowed for mail
17296 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
17297 too). This setting doesn't affect @samp{login-chroot}
17298 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
17299 "/./" in home dirs are ignored. WARNING: Never add directories here
17300 which local users can modify, that may lead to root exploit. Usually
17301 this should be done only if you don't allow shell access for users.
17302 <doc/wiki/Chrooting.txt>.
17303 Defaults to @samp{()}.
17306 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
17307 Default chroot directory for mail processes. This can be overridden
17308 for specific users in user database by giving /./ in user's home
17309 directory (e.g.@: /home/./user chroots into /home). Note that usually
17310 there is no real need to do chrooting, Dovecot doesn't allow users to
17311 access files outside their mail directory anyway. If your home
17312 directories are prefixed with the chroot directory, append "/."@: to
17313 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
17314 Defaults to @samp{""}.
17317 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
17318 UNIX socket path to master authentication server to find users.
17319 This is used by imap (for shared users) and lda.
17320 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17323 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
17324 Directory where to look up mail plugins.
17325 Defaults to @samp{"/usr/lib/dovecot"}.
17328 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
17329 List of plugins to load for all services. Plugins specific to IMAP,
17330 LDA, etc.@: are added to this list in their own .conf files.
17331 Defaults to @samp{()}.
17334 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
17335 The minimum number of mails in a mailbox before updates are done to
17336 cache file. This allows optimizing Dovecot's behavior to do less disk
17337 writes at the cost of more disk reads.
17338 Defaults to @samp{0}.
17341 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
17342 When IDLE command is running, mailbox is checked once in a while to
17343 see if there are any new mails or other changes. This setting defines
17344 the minimum time to wait between those checks. Dovecot can also use
17345 dnotify, inotify and kqueue to find out immediately when changes
17347 Defaults to @samp{"30 secs"}.
17350 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
17351 Save mails with CR+LF instead of plain LF. This makes sending those
17352 mails take less CPU, especially with sendfile() syscall with Linux and
17353 FreeBSD. But it also creates a bit more disk I/O which may just make it
17354 slower. Also note that if other software reads the mboxes/maildirs,
17355 they may handle the extra CRs wrong and cause problems.
17356 Defaults to @samp{#f}.
17359 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
17360 By default LIST command returns all entries in maildir beginning
17361 with a dot. Enabling this option makes Dovecot return only entries
17362 which are directories. This is done by stat()ing each entry, so it
17363 causes more disk I/O.
17364 (For systems setting struct @samp{dirent->d_type} this check is free
17365 and it's done always regardless of this setting).
17366 Defaults to @samp{#f}.
17369 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
17370 When copying a message, do it with hard links whenever possible.
17371 This makes the performance much better, and it's unlikely to have any
17373 Defaults to @samp{#t}.
17376 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
17377 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
17378 directory only when its mtime changes unexpectedly or when we can't find
17379 the mail otherwise.
17380 Defaults to @samp{#f}.
17383 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
17384 Which locking methods to use for locking mbox. There are four
17389 Create <mailbox>.lock file. This is the oldest and most NFS-safe
17390 solution. If you want to use /var/mail/ like directory, the users will
17391 need write access to that directory.
17393 Same as dotlock, but if it fails because of permissions or because there
17394 isn't enough disk space, just skip it.
17396 Use this if possible. Works with NFS too if lockd is used.
17398 May not exist in all systems. Doesn't work with NFS.
17400 May not exist in all systems. Doesn't work with NFS.
17403 You can use multiple locking methods; if you do the order they're declared
17404 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
17405 locking methods as well. Some operating systems don't allow using some of
17406 them simultaneously.
17409 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
17413 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
17414 Maximum time to wait for lock (all of them) before aborting.
17415 Defaults to @samp{"5 mins"}.
17418 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
17419 If dotlock exists but the mailbox isn't modified in any way,
17420 override the lock file after this much time.
17421 Defaults to @samp{"2 mins"}.
17424 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
17425 When mbox changes unexpectedly we have to fully read it to find out
17426 what changed. If the mbox is large this can take a long time. Since
17427 the change is usually just a newly appended mail, it'd be faster to
17428 simply read the new mails. If this setting is enabled, Dovecot does
17429 this but still safely fallbacks to re-reading the whole mbox file
17430 whenever something in mbox isn't how it's expected to be. The only real
17431 downside to this setting is that if some other MUA changes message
17432 flags, Dovecot doesn't notice it immediately. Note that a full sync is
17433 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
17434 Defaults to @samp{#t}.
17437 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
17438 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
17439 EXAMINE, EXPUNGE or CHECK commands. If this is set,
17440 @samp{mbox-dirty-syncs} is ignored.
17441 Defaults to @samp{#f}.
17444 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
17445 Delay writing mbox headers until doing a full write sync (EXPUNGE
17446 and CHECK commands and when closing the mailbox). This is especially
17447 useful for POP3 where clients often delete all mails. The downside is
17448 that our changes aren't immediately visible to other MUAs.
17449 Defaults to @samp{#t}.
17452 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
17453 If mbox size is smaller than this (e.g.@: 100k), don't write index
17454 files. If an index file already exists it's still read, just not
17456 Defaults to @samp{0}.
17459 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
17460 Maximum dbox file size until it's rotated.
17461 Defaults to @samp{10000000}.
17464 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
17465 Maximum dbox file age until it's rotated. Typically in days. Day
17466 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
17468 Defaults to @samp{"1d"}.
17471 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
17472 When creating new mdbox files, immediately preallocate their size to
17473 @samp{mdbox-rotate-size}. This setting currently works only in Linux
17474 with some file systems (ext4, xfs).
17475 Defaults to @samp{#f}.
17478 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
17479 sdbox and mdbox support saving mail attachments to external files,
17480 which also allows single instance storage for them. Other backends
17481 don't support this for now.
17483 WARNING: This feature hasn't been tested much yet. Use at your own risk.
17485 Directory root where to store mail attachments. Disabled, if empty.
17486 Defaults to @samp{""}.
17489 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
17490 Attachments smaller than this aren't saved externally. It's also
17491 possible to write a plugin to disable saving specific attachments
17493 Defaults to @samp{128000}.
17496 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
17497 File system backend to use for saving attachments:
17500 No SiS done by Dovecot (but this might help FS's own deduplication)
17502 SiS with immediate byte-by-byte comparison during saving
17503 @item sis-queue posix
17504 SiS with delayed comparison and deduplication.
17506 Defaults to @samp{"sis posix"}.
17509 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
17510 Hash format to use in attachment filenames. You can add any text and
17511 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
17512 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
17513 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
17514 Defaults to @samp{"%@{sha1@}"}.
17517 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
17519 Defaults to @samp{100}.
17522 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
17524 Defaults to @samp{1000}.
17527 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
17528 Default VSZ (virtual memory size) limit for service processes.
17529 This is mainly intended to catch and kill processes that leak memory
17530 before they eat up everything.
17531 Defaults to @samp{256000000}.
17534 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
17535 Login user is internally used by login processes. This is the most
17536 untrusted user in Dovecot system. It shouldn't have access to anything
17538 Defaults to @samp{"dovenull"}.
17541 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
17542 Internal user is used by unprivileged processes. It should be
17543 separate from login user, so that login processes can't disturb other
17545 Defaults to @samp{"dovecot"}.
17548 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
17549 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
17550 Defaults to @samp{"required"}.
17553 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
17554 PEM encoded X.509 SSL/TLS certificate (public key).
17555 Defaults to @samp{"</etc/dovecot/default.pem"}.
17558 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
17559 PEM encoded SSL/TLS private key. The key is opened before
17560 dropping root privileges, so keep the key file unreadable by anyone but
17562 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
17565 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
17566 If key file is password protected, give the password here.
17567 Alternatively give it when starting dovecot with -p parameter. Since
17568 this file is often world-readable, you may want to place this setting
17569 instead to a different.
17570 Defaults to @samp{""}.
17573 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
17574 PEM encoded trusted certificate authority. Set this only if you
17575 intend to use @samp{ssl-verify-client-cert? #t}. The file should
17576 contain the CA certificate(s) followed by the matching
17577 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
17578 Defaults to @samp{""}.
17581 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
17582 Require that CRL check succeeds for client certificates.
17583 Defaults to @samp{#t}.
17586 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
17587 Request client to send a certificate. If you also want to require
17588 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
17589 Defaults to @samp{#f}.
17592 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
17593 Which field from certificate to use for username. commonName and
17594 x500UniqueIdentifier are the usual choices. You'll also need to set
17595 @samp{auth-ssl-username-from-cert? #t}.
17596 Defaults to @samp{"commonName"}.
17599 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
17600 Minimum SSL protocol version to accept.
17601 Defaults to @samp{"TLSv1"}.
17604 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
17605 SSL ciphers to use.
17606 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
17609 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
17610 SSL crypto device to use, for valid values run "openssl engine".
17611 Defaults to @samp{""}.
17614 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
17615 Address to use when sending rejection mails.
17616 %d expands to recipient domain.
17617 Defaults to @samp{"postmaster@@%d"}.
17620 @deftypevr {@code{dovecot-configuration} parameter} string hostname
17621 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
17622 and in LMTP replies. Default is the system's real hostname@@domain.
17623 Defaults to @samp{""}.
17626 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
17627 If user is over quota, return with temporary failure instead of
17629 Defaults to @samp{#f}.
17632 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
17633 Binary to use for sending mails.
17634 Defaults to @samp{"/usr/sbin/sendmail"}.
17637 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
17638 If non-empty, send mails via this SMTP host[:port] instead of
17640 Defaults to @samp{""}.
17643 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
17644 Subject: header to use for rejection mails. You can use the same
17645 variables as for @samp{rejection-reason} below.
17646 Defaults to @samp{"Rejected: %s"}.
17649 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
17650 Human readable error message for rejection mails. You can use
17663 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
17666 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
17667 Delimiter character between local-part and detail in email
17669 Defaults to @samp{"+"}.
17672 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
17673 Header where the original recipient address (SMTP's RCPT TO:
17674 address) is taken from if not available elsewhere. With dovecot-lda -a
17675 parameter overrides this. A commonly used header for this is
17677 Defaults to @samp{""}.
17680 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
17681 Should saving a mail to a nonexistent mailbox automatically create
17683 Defaults to @samp{#f}.
17686 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
17687 Should automatically created mailboxes be also automatically
17689 Defaults to @samp{#f}.
17692 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
17693 Maximum IMAP command line length. Some clients generate very long
17694 command lines with huge mailboxes, so you may need to raise this if you
17695 get "Too long argument" or "IMAP command line too large" errors
17697 Defaults to @samp{64000}.
17700 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
17701 IMAP logout format string:
17704 total number of bytes read from client
17706 total number of bytes sent to client.
17708 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
17709 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@}"}.
17712 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
17713 Override the IMAP CAPABILITY response. If the value begins with '+',
17714 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
17715 Defaults to @samp{""}.
17718 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
17719 How long to wait between "OK Still here" notifications when client
17721 Defaults to @samp{"2 mins"}.
17724 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
17725 ID field names and values to send to clients. Using * as the value
17726 makes Dovecot use the default value. The following fields have default
17727 values currently: name, version, os, os-version, support-url,
17729 Defaults to @samp{""}.
17732 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
17733 ID fields sent by client to log. * means everything.
17734 Defaults to @samp{""}.
17737 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
17738 Workarounds for various client bugs:
17741 @item delay-newmail
17742 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
17743 CHECK commands. Some clients ignore them otherwise, for example OSX
17744 Mail (<v2.1). Outlook Express breaks more badly though, without this it
17745 may show user "Message no longer in server" errors. Note that OE6
17746 still breaks even with this workaround if synchronization is set to
17749 @item tb-extra-mailbox-sep
17750 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
17751 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
17752 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
17754 @item tb-lsub-flags
17755 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
17756 This makes Thunderbird realize they aren't selectable and show them
17757 greyed out, instead of only later giving "not selectable" popup error.
17759 Defaults to @samp{()}.
17762 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
17763 Host allowed in URLAUTH URLs sent by client. "*" allows all.
17764 Defaults to @samp{""}.
17768 Whew! Lots of configuration options. The nice thing about it though is
17769 that Guix has a complete interface to Dovecot's configuration
17770 language. This allows not only a nice way to declare configurations,
17771 but also offers reflective capabilities as well: users can write code to
17772 inspect and transform configurations from within Scheme.
17774 However, it could be that you just want to get a @code{dovecot.conf} up
17775 and running. In that case, you can pass an
17776 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
17777 @code{dovecot-service}. As its name indicates, an opaque configuration
17778 does not have easy reflective capabilities.
17780 Available @code{opaque-dovecot-configuration} fields are:
17782 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
17783 The dovecot package.
17786 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
17787 The contents of the @code{dovecot.conf}, as a string.
17790 For example, if your @code{dovecot.conf} is just the empty string, you
17791 could instantiate a dovecot service like this:
17794 (dovecot-service #:config
17795 (opaque-dovecot-configuration
17799 @subsubheading OpenSMTPD Service
17801 @deffn {Scheme Variable} opensmtpd-service-type
17802 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
17803 service, whose value should be an @code{opensmtpd-configuration} object
17804 as in this example:
17807 (service opensmtpd-service-type
17808 (opensmtpd-configuration
17809 (config-file (local-file "./my-smtpd.conf"))))
17813 @deftp {Data Type} opensmtpd-configuration
17814 Data type representing the configuration of opensmtpd.
17817 @item @code{package} (default: @var{opensmtpd})
17818 Package object of the OpenSMTPD SMTP server.
17820 @item @code{config-file} (default: @code{%default-opensmtpd-file})
17821 File-like object of the OpenSMTPD configuration file to use. By default
17822 it listens on the loopback network interface, and allows for mail from
17823 users and daemons on the local machine, as well as permitting email to
17824 remote servers. Run @command{man smtpd.conf} for more information.
17829 @subsubheading Exim Service
17831 @cindex mail transfer agent (MTA)
17832 @cindex MTA (mail transfer agent)
17835 @deffn {Scheme Variable} exim-service-type
17836 This is the type of the @uref{https://exim.org, Exim} mail transfer
17837 agent (MTA), whose value should be an @code{exim-configuration} object
17838 as in this example:
17841 (service exim-service-type
17842 (exim-configuration
17843 (config-file (local-file "./my-exim.conf"))))
17847 In order to use an @code{exim-service-type} service you must also have a
17848 @code{mail-aliases-service-type} service present in your
17849 @code{operating-system} (even if it has no aliases).
17851 @deftp {Data Type} exim-configuration
17852 Data type representing the configuration of exim.
17855 @item @code{package} (default: @var{exim})
17856 Package object of the Exim server.
17858 @item @code{config-file} (default: @code{#f})
17859 File-like object of the Exim configuration file to use. If its value is
17860 @code{#f} then use the default configuration file from the package
17861 provided in @code{package}. The resulting configuration file is loaded
17862 after setting the @code{exim_user} and @code{exim_group} configuration
17868 @subsubheading Getmail service
17873 @deffn {Scheme Variable} getmail-service-type
17874 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
17875 mail retriever, whose value should be an @code{getmail-configuration}.
17878 Available @code{getmail-configuration} fields are:
17880 @deftypevr {@code{getmail-configuration} parameter} symbol name
17881 A symbol to identify the getmail service.
17883 Defaults to @samp{"unset"}.
17887 @deftypevr {@code{getmail-configuration} parameter} package package
17888 The getmail package to use.
17892 @deftypevr {@code{getmail-configuration} parameter} string user
17893 The user to run getmail as.
17895 Defaults to @samp{"getmail"}.
17899 @deftypevr {@code{getmail-configuration} parameter} string group
17900 The group to run getmail as.
17902 Defaults to @samp{"getmail"}.
17906 @deftypevr {@code{getmail-configuration} parameter} string directory
17907 The getmail directory to use.
17909 Defaults to @samp{"/var/lib/getmail/default"}.
17913 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
17914 The getmail configuration file to use.
17916 Available @code{getmail-configuration-file} fields are:
17918 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
17919 What mail account to retrieve mail from, and how to access that account.
17921 Available @code{getmail-retriever-configuration} fields are:
17923 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
17924 The type of mail retriever to use. Valid values include @samp{passwd}
17927 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
17931 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
17932 Username to login to the mail server with.
17934 Defaults to @samp{unset}.
17938 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
17939 Username to login to the mail server with.
17941 Defaults to @samp{unset}.
17945 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
17946 Port number to connect to.
17948 Defaults to @samp{#f}.
17952 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
17953 Override fields from passwd.
17955 Defaults to @samp{""}.
17959 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
17960 Override fields from passwd.
17962 Defaults to @samp{()}.
17966 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
17967 PEM-formatted key file to use for the TLS negotiation.
17969 Defaults to @samp{""}.
17973 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
17974 PEM-formatted certificate file to use for the TLS negotiation.
17976 Defaults to @samp{""}.
17980 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
17981 CA certificates to use.
17983 Defaults to @samp{""}.
17987 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
17988 Extra retriever parameters.
17990 Defaults to @samp{()}.
17996 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
17997 What to do with retrieved messages.
17999 Available @code{getmail-destination-configuration} fields are:
18001 @deftypevr {@code{getmail-destination-configuration} parameter} string type
18002 The type of mail destination. Valid values include @samp{Maildir},
18003 @samp{Mboxrd} and @samp{MDA_external}.
18005 Defaults to @samp{unset}.
18009 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
18010 The path option for the mail destination. The behaviour depends on the
18013 Defaults to @samp{""}.
18017 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
18018 Extra destination parameters
18020 Defaults to @samp{()}.
18026 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
18029 Available @code{getmail-options-configuration} fields are:
18031 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
18032 If set to @samp{0}, getmail will only print warnings and errors. A
18033 value of @samp{1} means that messages will be printed about retrieving
18034 and deleting messages. If set to @samp{2}, getmail will print messages
18035 about each of it's actions.
18037 Defaults to @samp{1}.
18041 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
18042 If true, getmail will retrieve all available messages. Otherwise it
18043 will only retrieve messages it hasn't seen previously.
18045 Defaults to @samp{#t}.
18049 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
18050 If set to true, messages will be deleted from the server after
18051 retrieving and successfully delivering them. Otherwise, messages will
18052 be left on the server.
18054 Defaults to @samp{#f}.
18058 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
18059 Getmail will delete messages this number of days after seeing them, if
18060 they have been delivered. This means messages will be left on the
18061 server this number of days after delivering them. A value of @samp{0}
18062 disabled this feature.
18064 Defaults to @samp{0}.
18068 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
18069 Delete messages larger than this of bytes after retrieving them, even if
18070 the delete and delete-after options are disabled. A value of @samp{0}
18071 disables this feature.
18073 Defaults to @samp{0}.
18077 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
18078 Retrieve messages totalling up to this number of bytes before closing
18079 the session with the server. A value of @samp{0} disables this feature.
18081 Defaults to @samp{0}.
18085 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
18086 Don't retrieve messages larger than this number of bytes. A value of
18087 @samp{0} disables this feature.
18089 Defaults to @samp{0}.
18093 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
18094 If true, getmail will add a Delivered-To header to messages.
18096 Defaults to @samp{#t}.
18100 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
18101 If set, getmail adds a Received header to the messages.
18103 Defaults to @samp{#t}.
18107 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
18108 Getmail will record a log of its actions to the named file. A value of
18109 @samp{""} disables this feature.
18111 Defaults to @samp{""}.
18115 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
18116 If true, getmail will record a log of its actions using the system
18119 Defaults to @samp{#f}.
18123 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
18124 If true, getmail will log information about messages not retrieved and
18125 the reason for not retrieving them, as well as starting and ending
18128 Defaults to @samp{#f}.
18132 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
18133 Extra options to include.
18135 Defaults to @samp{()}.
18143 @deftypevr {@code{getmail-configuration} parameter} list idle
18144 A list of mailboxes that getmail should wait on the server for new mail
18145 notifications. This depends on the server supporting the IDLE
18148 Defaults to @samp{()}.
18152 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
18153 Environment variables to set for getmail.
18155 Defaults to @samp{()}.
18159 @subsubheading Mail Aliases Service
18161 @cindex email aliases
18162 @cindex aliases, for email addresses
18164 @deffn {Scheme Variable} mail-aliases-service-type
18165 This is the type of the service which provides @code{/etc/aliases},
18166 specifying how to deliver mail to users on this system.
18169 (service mail-aliases-service-type
18170 '(("postmaster" "bob")
18171 ("bob" "bob@@example.com" "bob@@example2.com")))
18175 The configuration for a @code{mail-aliases-service-type} service is an
18176 association list denoting how to deliver mail that comes to this
18177 system. Each entry is of the form @code{(alias addresses ...)}, with
18178 @code{alias} specifying the local alias and @code{addresses} specifying
18179 where to deliver this user's mail.
18181 The aliases aren't required to exist as users on the local system. In
18182 the above example, there doesn't need to be a @code{postmaster} entry in
18183 the @code{operating-system}'s @code{user-accounts} in order to deliver
18184 the @code{postmaster} mail to @code{bob} (which subsequently would
18185 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
18187 @subsubheading GNU Mailutils IMAP4 Daemon
18188 @cindex GNU Mailutils IMAP4 Daemon
18190 @deffn {Scheme Variable} imap4d-service-type
18191 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
18192 mailutils, GNU Mailutils Manual}), whose value should be an
18193 @code{imap4d-configuration} object as in this example:
18196 (service imap4d-service-type
18197 (imap4d-configuration
18198 (config-file (local-file "imap4d.conf"))))
18202 @deftp {Data Type} imap4d-configuration
18203 Data type representing the configuration of @command{imap4d}.
18206 @item @code{package} (default: @code{mailutils})
18207 The package that provides @command{imap4d}.
18209 @item @code{config-file} (default: @code{%default-imap4d-config-file})
18210 File-like object of the configuration file to use, by default it will listen
18211 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
18212 Mailutils Manual}, for details.
18217 @node Messaging Services
18218 @subsection Messaging Services
18223 The @code{(gnu services messaging)} module provides Guix service
18224 definitions for messaging services: currently only Prosody is supported.
18226 @subsubheading Prosody Service
18228 @deffn {Scheme Variable} prosody-service-type
18229 This is the type for the @uref{https://prosody.im, Prosody XMPP
18230 communication server}. Its value must be a @code{prosody-configuration}
18231 record as in this example:
18234 (service prosody-service-type
18235 (prosody-configuration
18236 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
18239 (int-component-configuration
18240 (hostname "conference.example.net")
18242 (mod-muc (mod-muc-configuration)))))
18245 (virtualhost-configuration
18246 (domain "example.net"))))))
18249 See below for details about @code{prosody-configuration}.
18253 By default, Prosody does not need much configuration. Only one
18254 @code{virtualhosts} field is needed: it specifies the domain you wish
18257 You can perform various sanity checks on the generated configuration
18258 with the @code{prosodyctl check} command.
18260 Prosodyctl will also help you to import certificates from the
18261 @code{letsencrypt} directory so that the @code{prosody} user can access
18262 them. See @url{https://prosody.im/doc/letsencrypt}.
18265 prosodyctl --root cert import /etc/letsencrypt/live
18268 The available configuration parameters follow. Each parameter
18269 definition is preceded by its type; for example, @samp{string-list foo}
18270 indicates that the @code{foo} parameter should be specified as a list of
18271 strings. Types starting with @code{maybe-} denote parameters that won't
18272 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
18274 There is also a way to specify the configuration as a string, if you
18275 have an old @code{prosody.cfg.lua} file that you want to port over from
18276 some other system; see the end for more details.
18278 The @code{file-object} type designates either a file-like object
18279 (@pxref{G-Expressions, file-like objects}) or a file name.
18281 @c The following documentation was initially generated by
18282 @c (generate-documentation) in (gnu services messaging). Manually maintained
18283 @c documentation is better, so we shouldn't hesitate to edit below as
18284 @c needed. However if the change you want to make to this documentation
18285 @c can be done in an automated way, it's probably easier to change
18286 @c (generate-documentation) than to make it below and have to deal with
18287 @c the churn as Prosody updates.
18289 Available @code{prosody-configuration} fields are:
18291 @deftypevr {@code{prosody-configuration} parameter} package prosody
18292 The Prosody package.
18295 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
18296 Location of the Prosody data storage directory. See
18297 @url{https://prosody.im/doc/configure}.
18298 Defaults to @samp{"/var/lib/prosody"}.
18301 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
18302 Additional plugin directories. They are searched in all the specified
18303 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
18304 Defaults to @samp{()}.
18307 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
18308 Every virtual host and component needs a certificate so that clients and
18309 servers can securely verify its identity. Prosody will automatically load
18310 certificates/keys from the directory specified here.
18311 Defaults to @samp{"/etc/prosody/certs"}.
18314 @deftypevr {@code{prosody-configuration} parameter} string-list admins
18315 This is a list of accounts that are admins for the server. Note that you
18316 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
18317 @url{https://prosody.im/doc/creating_accounts}.
18318 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
18319 Defaults to @samp{()}.
18322 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
18323 Enable use of libevent for better performance under high load. See
18324 @url{https://prosody.im/doc/libevent}.
18325 Defaults to @samp{#f}.
18328 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
18329 This is the list of modules Prosody will load on startup. It looks for
18330 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
18331 Documentation on modules can be found at:
18332 @url{https://prosody.im/doc/modules}.
18333 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
18336 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
18337 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
18338 should you want to disable them then add them to this list.
18339 Defaults to @samp{()}.
18342 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
18343 Path to a text file where the shared groups are defined. If this path is
18344 empty then @samp{mod_groups} does nothing. See
18345 @url{https://prosody.im/doc/modules/mod_groups}.
18346 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
18349 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
18350 Disable account creation by default, for security. See
18351 @url{https://prosody.im/doc/creating_accounts}.
18352 Defaults to @samp{#f}.
18355 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
18356 These are the SSL/TLS-related settings. Most of them are disabled so to
18357 use Prosody's defaults. If you do not completely understand these options, do
18358 not add them to your config, it is easy to lower the security of your server
18359 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
18361 Available @code{ssl-configuration} fields are:
18363 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
18364 This determines what handshake to use.
18367 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
18368 Path to your private key file.
18371 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
18372 Path to your certificate file.
18375 @deftypevr {@code{ssl-configuration} parameter} file-object capath
18376 Path to directory containing root certificates that you wish Prosody to
18377 trust when verifying the certificates of remote servers.
18378 Defaults to @samp{"/etc/ssl/certs"}.
18381 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
18382 Path to a file containing root certificates that you wish Prosody to trust.
18383 Similar to @code{capath} but with all certificates concatenated together.
18386 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
18387 A list of verification options (these mostly map to OpenSSL's
18388 @code{set_verify()} flags).
18391 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
18392 A list of general options relating to SSL/TLS. These map to OpenSSL's
18393 @code{set_options()}. For a full list of options available in LuaSec, see the
18397 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
18398 How long a chain of certificate authorities to check when looking for a
18399 trusted root certificate.
18402 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
18403 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
18404 clients, and in what order.
18407 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
18408 A path to a file containing parameters for Diffie-Hellman key exchange. You
18409 can create such a file with:
18410 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
18413 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
18414 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
18415 @samp{"secp384r1"}.
18418 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
18419 A list of "extra" verification options.
18422 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
18423 Password for encrypted private keys.
18428 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
18429 Whether to force all client-to-server connections to be encrypted or not.
18430 See @url{https://prosody.im/doc/modules/mod_tls}.
18431 Defaults to @samp{#f}.
18434 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
18435 Set of mechanisms that will never be offered. See
18436 @url{https://prosody.im/doc/modules/mod_saslauth}.
18437 Defaults to @samp{("DIGEST-MD5")}.
18440 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
18441 Whether to force all server-to-server connections to be encrypted or not.
18442 See @url{https://prosody.im/doc/modules/mod_tls}.
18443 Defaults to @samp{#f}.
18446 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
18447 Whether to require encryption and certificate authentication. This
18448 provides ideal security, but requires servers you communicate with to support
18449 encryption AND present valid, trusted certificates. See
18450 @url{https://prosody.im/doc/s2s#security}.
18451 Defaults to @samp{#f}.
18454 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
18455 Many servers don't support encryption or have invalid or self-signed
18456 certificates. You can list domains here that will not be required to
18457 authenticate using certificates. They will be authenticated using DNS. See
18458 @url{https://prosody.im/doc/s2s#security}.
18459 Defaults to @samp{()}.
18462 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
18463 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
18464 valid certificates for some domains by specifying a list here. See
18465 @url{https://prosody.im/doc/s2s#security}.
18466 Defaults to @samp{()}.
18469 @deftypevr {@code{prosody-configuration} parameter} string authentication
18470 Select the authentication backend to use. The default provider stores
18471 passwords in plaintext and uses Prosody's configured data storage to store the
18472 authentication data. If you do not trust your server please see
18473 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
18474 about using the hashed backend. See also
18475 @url{https://prosody.im/doc/authentication}
18476 Defaults to @samp{"internal_plain"}.
18479 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
18480 Set logging options. Advanced logging configuration is not yet supported
18481 by the Prosody service. See @url{https://prosody.im/doc/logging}.
18482 Defaults to @samp{"*syslog"}.
18485 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
18486 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
18487 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
18490 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
18491 Maximum allowed size of the HTTP body (in bytes).
18494 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
18495 Some modules expose their own URL in various ways. This URL is built
18496 from the protocol, host and port used. If Prosody sits behind a proxy, the
18497 public URL will be @code{http-external-url} instead. See
18498 @url{https://prosody.im/doc/http#external_url}.
18501 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
18502 A host in Prosody is a domain on which user accounts can be created. For
18503 example if you want your users to have addresses like
18504 @samp{"john.smith@@example.com"} then you need to add a host
18505 @samp{"example.com"}. All options in this list will apply only to this host.
18507 Note: the name "virtual" host is used in configuration to avoid confusion with
18508 the actual physical host that Prosody is installed on. A single Prosody
18509 instance can serve many domains, each one defined as a VirtualHost entry in
18510 Prosody's configuration. Conversely a server that hosts a single domain would
18511 have just one VirtualHost entry.
18513 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
18515 Available @code{virtualhost-configuration} fields are:
18517 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:
18518 @deftypevr {@code{virtualhost-configuration} parameter} string domain
18519 Domain you wish Prosody to serve.
18524 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
18525 Components are extra services on a server which are available to clients,
18526 usually on a subdomain of the main server (such as
18527 @samp{"mycomponent.example.com"}). Example components might be chatroom
18528 servers, user directories, or gateways to other protocols.
18530 Internal components are implemented with Prosody-specific plugins. To add an
18531 internal component, you simply fill the hostname field, and the plugin you wish
18532 to use for the component.
18534 See @url{https://prosody.im/doc/components}.
18535 Defaults to @samp{()}.
18537 Available @code{int-component-configuration} fields are:
18539 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:
18540 @deftypevr {@code{int-component-configuration} parameter} string hostname
18541 Hostname of the component.
18544 @deftypevr {@code{int-component-configuration} parameter} string plugin
18545 Plugin you wish to use for the component.
18548 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
18549 Multi-user chat (MUC) is Prosody's module for allowing you to create
18550 hosted chatrooms/conferences for XMPP users.
18552 General information on setting up and using multi-user chatrooms can be found
18553 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
18554 which you should read if you are new to XMPP chatrooms.
18556 See also @url{https://prosody.im/doc/modules/mod_muc}.
18558 Available @code{mod-muc-configuration} fields are:
18560 @deftypevr {@code{mod-muc-configuration} parameter} string name
18561 The name to return in service discovery responses.
18562 Defaults to @samp{"Prosody Chatrooms"}.
18565 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
18566 If @samp{#t}, this will only allow admins to create new chatrooms.
18567 Otherwise anyone can create a room. The value @samp{"local"} restricts room
18568 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
18569 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
18570 restricts to service administrators only.
18571 Defaults to @samp{#f}.
18574 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
18575 Maximum number of history messages that will be sent to the member that has
18576 just joined the room.
18577 Defaults to @samp{20}.
18584 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
18585 External components use XEP-0114, which most standalone components
18586 support. To add an external component, you simply fill the hostname field. See
18587 @url{https://prosody.im/doc/components}.
18588 Defaults to @samp{()}.
18590 Available @code{ext-component-configuration} fields are:
18592 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:
18593 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
18594 Password which the component will use to log in.
18597 @deftypevr {@code{ext-component-configuration} parameter} string hostname
18598 Hostname of the component.
18603 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
18604 Port(s) Prosody listens on for component connections.
18605 Defaults to @samp{(5347)}.
18608 @deftypevr {@code{prosody-configuration} parameter} string component-interface
18609 Interface Prosody listens on for component connections.
18610 Defaults to @samp{"127.0.0.1"}.
18613 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
18614 Raw content that will be added to the configuration file.
18617 It could be that you just want to get a @code{prosody.cfg.lua}
18618 up and running. In that case, you can pass an
18619 @code{opaque-prosody-configuration} record as the value of
18620 @code{prosody-service-type}. As its name indicates, an opaque configuration
18621 does not have easy reflective capabilities.
18622 Available @code{opaque-prosody-configuration} fields are:
18624 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
18625 The prosody package.
18628 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
18629 The contents of the @code{prosody.cfg.lua} to use.
18632 For example, if your @code{prosody.cfg.lua} is just the empty
18633 string, you could instantiate a prosody service like this:
18636 (service prosody-service-type
18637 (opaque-prosody-configuration
18638 (prosody.cfg.lua "")))
18641 @c end of Prosody auto-generated documentation
18643 @subsubheading BitlBee Service
18645 @cindex IRC (Internet Relay Chat)
18646 @cindex IRC gateway
18647 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
18648 interface to a variety of messaging protocols such as XMPP.
18650 @defvr {Scheme Variable} bitlbee-service-type
18651 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
18652 gateway daemon. Its value is a @code{bitlbee-configuration} (see
18655 To have BitlBee listen on port 6667 on localhost, add this line to your
18659 (service bitlbee-service-type)
18663 @deftp {Data Type} bitlbee-configuration
18664 This is the configuration for BitlBee, with the following fields:
18667 @item @code{interface} (default: @code{"127.0.0.1"})
18668 @itemx @code{port} (default: @code{6667})
18669 Listen on the network interface corresponding to the IP address
18670 specified in @var{interface}, on @var{port}.
18672 When @var{interface} is @code{127.0.0.1}, only local clients can
18673 connect; when it is @code{0.0.0.0}, connections can come from any
18674 networking interface.
18676 @item @code{bitlbee} (default: @code{bitlbee})
18677 The BitlBee package to use.
18679 @item @code{plugins} (default: @code{'()})
18680 List of plugin packages to use---e.g., @code{bitlbee-discord}.
18682 @item @code{extra-settings} (default: @code{""})
18683 Configuration snippet added as-is to the BitlBee configuration file.
18687 @subsubheading Quassel Service
18689 @cindex IRC (Internet Relay Chat)
18690 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
18691 meaning that one or more clients can attach to and detach from the
18694 @defvr {Scheme Variable} quassel-service-type
18695 This is the service type for the @url{https://quassel-irc.org/,Quassel}
18696 IRC backend daemon. Its value is a @code{quassel-configuration}
18700 @deftp {Data Type} quassel-configuration
18701 This is the configuration for Quassel, with the following fields:
18704 @item @code{quassel} (default: @code{quassel})
18705 The Quassel package to use.
18707 @item @code{interface} (default: @code{"::,0.0.0.0"})
18708 @item @code{port} (default: @code{4242})
18709 Listen on the network interface(s) corresponding to the IPv4 or IPv6
18710 interfaces specified in the comma delimited @var{interface}, on
18713 @item @code{loglevel} (default: @code{"Info"})
18714 The level of logging desired. Accepted values are Debug, Info, Warning
18719 @node Telephony Services
18720 @subsection Telephony Services
18722 @cindex Murmur (VoIP server)
18723 @cindex VoIP server
18724 This section describes how to set up and run a Murmur server. Murmur is
18725 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
18728 @deftp {Data Type} murmur-configuration
18729 The service type for the Murmur server. An example configuration can
18733 (service murmur-service-type
18734 (murmur-configuration
18736 "Welcome to this Mumble server running on Guix!")
18737 (cert-required? #t) ;disallow text password logins
18738 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
18739 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
18742 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
18743 password with the command that is printed during the activation phase.
18745 It is recommended to register a normal Mumble user account
18746 and grant it admin or moderator rights.
18747 You can use the @code{mumble} client to
18748 login as new normal user, register yourself, and log out.
18749 For the next step login with the name @code{SuperUser} use
18750 the @code{SuperUser} password that you set previously,
18751 and grant your newly registered mumble user administrator or moderator
18752 rights and create some channels.
18754 Available @code{murmur-configuration} fields are:
18757 @item @code{package} (default: @code{mumble})
18758 Package that contains @code{bin/murmurd}.
18760 @item @code{user} (default: @code{"murmur"})
18761 User who will run the Murmur server.
18763 @item @code{group} (default: @code{"murmur"})
18764 Group of the user who will run the murmur server.
18766 @item @code{port} (default: @code{64738})
18767 Port on which the server will listen.
18769 @item @code{welcome-text} (default: @code{""})
18770 Welcome text sent to clients when they connect.
18772 @item @code{server-password} (default: @code{""})
18773 Password the clients have to enter in order to connect.
18775 @item @code{max-users} (default: @code{100})
18776 Maximum of users that can be connected to the server at once.
18778 @item @code{max-user-bandwidth} (default: @code{#f})
18779 Maximum voice traffic a user can send per second.
18781 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
18782 File name of the sqlite database.
18783 The service's user will become the owner of the directory.
18785 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
18786 File name of the log file.
18787 The service's user will become the owner of the directory.
18789 @item @code{autoban-attempts} (default: @code{10})
18790 Maximum number of logins a user can make in @code{autoban-timeframe}
18791 without getting auto banned for @code{autoban-time}.
18793 @item @code{autoban-timeframe} (default: @code{120})
18794 Timeframe for autoban in seconds.
18796 @item @code{autoban-time} (default: @code{300})
18797 Amount of time in seconds for which a client gets banned
18798 when violating the autoban limits.
18800 @item @code{opus-threshold} (default: @code{100})
18801 Percentage of clients that need to support opus
18802 before switching over to opus audio codec.
18804 @item @code{channel-nesting-limit} (default: @code{10})
18805 How deep channels can be nested at maximum.
18807 @item @code{channelname-regex} (default: @code{#f})
18808 A string in form of a Qt regular expression that channel names must conform to.
18810 @item @code{username-regex} (default: @code{#f})
18811 A string in form of a Qt regular expression that user names must conform to.
18813 @item @code{text-message-length} (default: @code{5000})
18814 Maximum size in bytes that a user can send in one text chat message.
18816 @item @code{image-message-length} (default: @code{(* 128 1024)})
18817 Maximum size in bytes that a user can send in one image message.
18819 @item @code{cert-required?} (default: @code{#f})
18820 If it is set to @code{#t} clients that use weak password authentication
18821 will not be accepted. Users must have completed the certificate wizard to join.
18823 @item @code{remember-channel?} (default: @code{#f})
18824 Should murmur remember the last channel each user was in when they disconnected
18825 and put them into the remembered channel when they rejoin.
18827 @item @code{allow-html?} (default: @code{#f})
18828 Should html be allowed in text messages, user comments, and channel descriptions.
18830 @item @code{allow-ping?} (default: @code{#f})
18831 Setting to true exposes the current user count, the maximum user count, and
18832 the server's maximum bandwidth per client to unauthenticated users. In the
18833 Mumble client, this information is shown in the Connect dialog.
18835 Disabling this setting will prevent public listing of the server.
18837 @item @code{bonjour?} (default: @code{#f})
18838 Should the server advertise itself in the local network through the bonjour protocol.
18840 @item @code{send-version?} (default: @code{#f})
18841 Should the murmur server version be exposed in ping requests.
18843 @item @code{log-days} (default: @code{31})
18844 Murmur also stores logs in the database, which are accessible via RPC.
18845 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
18846 or -1 to disable logging to the database.
18848 @item @code{obfuscate-ips?} (default: @code{#t})
18849 Should logged ips be obfuscated to protect the privacy of users.
18851 @item @code{ssl-cert} (default: @code{#f})
18852 File name of the SSL/TLS certificate used for encrypted connections.
18855 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
18857 @item @code{ssl-key} (default: @code{#f})
18858 Filepath to the ssl private key used for encrypted connections.
18860 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
18863 @item @code{ssl-dh-params} (default: @code{#f})
18864 File name of a PEM-encoded file with Diffie-Hellman parameters
18865 for the SSL/TLS encryption. Alternatively you set it to
18866 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
18867 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
18869 @item @code{ssl-ciphers} (default: @code{#f})
18870 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
18873 This option is specified using
18874 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
18875 OpenSSL cipher list notation}.
18877 It is recommended that you try your cipher string using 'openssl ciphers <string>'
18878 before setting it here, to get a feel for which cipher suites you will get.
18879 After setting this option, it is recommend that you inspect your Murmur log
18880 to ensure that Murmur is using the cipher suites that you expected it to.
18882 Note: Changing this option may impact the backwards compatibility of your
18883 Murmur server, and can remove the ability for older Mumble clients to be able
18886 @item @code{public-registration} (default: @code{#f})
18887 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
18889 You can optionally register your server in the public server list that the
18890 @code{mumble} client shows on startup.
18891 You cannot register your server if you have set a @code{server-password},
18892 or set @code{allow-ping} to @code{#f}.
18894 It might take a few hours until it shows up in the public list.
18896 @item @code{file} (default: @code{#f})
18897 Optional alternative override for this configuration.
18901 @deftp {Data Type} murmur-public-registration-configuration
18902 Configuration for public registration of a murmur service.
18906 This is a display name for your server. Not to be confused with the hostname.
18908 @item @code{password}
18909 A password to identify your registration.
18910 Subsequent updates will need the same password. Don't lose your password.
18913 This should be a @code{http://} or @code{https://} link to your web
18916 @item @code{hostname} (default: @code{#f})
18917 By default your server will be listed by its IP address.
18918 If it is set your server will be linked by this host name instead.
18924 @node Monitoring Services
18925 @subsection Monitoring Services
18927 @subsubheading Tailon Service
18929 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
18930 viewing and searching log files.
18932 The following example will configure the service with default values.
18933 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
18936 (service tailon-service-type)
18939 The following example customises more of the Tailon configuration,
18940 adding @command{sed} to the list of allowed commands.
18943 (service tailon-service-type
18944 (tailon-configuration
18946 (tailon-configuration-file
18947 (allowed-commands '("tail" "grep" "awk" "sed"))))))
18951 @deftp {Data Type} tailon-configuration
18952 Data type representing the configuration of Tailon.
18953 This type has the following parameters:
18956 @item @code{config-file} (default: @code{(tailon-configuration-file)})
18957 The configuration file to use for Tailon. This can be set to a
18958 @dfn{tailon-configuration-file} record value, or any gexp
18959 (@pxref{G-Expressions}).
18961 For example, to instead use a local file, the @code{local-file} function
18965 (service tailon-service-type
18966 (tailon-configuration
18967 (config-file (local-file "./my-tailon.conf"))))
18970 @item @code{package} (default: @code{tailon})
18971 The tailon package to use.
18976 @deftp {Data Type} tailon-configuration-file
18977 Data type representing the configuration options for Tailon.
18978 This type has the following parameters:
18981 @item @code{files} (default: @code{(list "/var/log")})
18982 List of files to display. The list can include strings for a single file
18983 or directory, or a list, where the first item is the name of a
18984 subsection, and the remaining items are the files or directories in that
18987 @item @code{bind} (default: @code{"localhost:8080"})
18988 Address and port to which Tailon should bind on.
18990 @item @code{relative-root} (default: @code{#f})
18991 URL path to use for Tailon, set to @code{#f} to not use a path.
18993 @item @code{allow-transfers?} (default: @code{#t})
18994 Allow downloading the log files in the web interface.
18996 @item @code{follow-names?} (default: @code{#t})
18997 Allow tailing of not-yet existent files.
18999 @item @code{tail-lines} (default: @code{200})
19000 Number of lines to read initially from each file.
19002 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
19003 Commands to allow running. By default, @code{sed} is disabled.
19005 @item @code{debug?} (default: @code{#f})
19006 Set @code{debug?} to @code{#t} to show debug messages.
19008 @item @code{wrap-lines} (default: @code{#t})
19009 Initial line wrapping state in the web interface. Set to @code{#t} to
19010 initially wrap lines (the default), or to @code{#f} to initially not
19013 @item @code{http-auth} (default: @code{#f})
19014 HTTP authentication type to use. Set to @code{#f} to disable
19015 authentication (the default). Supported values are @code{"digest"} or
19018 @item @code{users} (default: @code{#f})
19019 If HTTP authentication is enabled (see @code{http-auth}), access will be
19020 restricted to the credentials provided here. To configure users, use a
19021 list of pairs, where the first element of the pair is the username, and
19022 the 2nd element of the pair is the password.
19025 (tailon-configuration-file
19026 (http-auth "basic")
19027 (users '(("user1" . "password1")
19028 ("user2" . "password2"))))
19035 @subsubheading Darkstat Service
19037 Darkstat is a packet sniffer that captures network traffic, calculates
19038 statistics about usage, and serves reports over HTTP.
19040 @defvar {Scheme Variable} darkstat-service-type
19041 This is the service type for the
19042 @uref{https://unix4lyfe.org/darkstat/, darkstat}
19043 service, its value must be a @code{darkstat-configuration} record as in
19047 (service darkstat-service-type
19048 (darkstat-configuration
19049 (interface "eno1")))
19053 @deftp {Data Type} darkstat-configuration
19054 Data type representing the configuration of @command{darkstat}.
19057 @item @code{package} (default: @code{darkstat})
19058 The darkstat package to use.
19060 @item @code{interface}
19061 Capture traffic on the specified network interface.
19063 @item @code{port} (default: @code{"667"})
19064 Bind the web interface to the specified port.
19066 @item @code{bind-address} (default: @code{"127.0.0.1"})
19067 Bind the web interface to the specified address.
19069 @item @code{base} (default: @code{"/"})
19070 Specify the path of the base URL. This can be useful if
19071 @command{darkstat} is accessed via a reverse proxy.
19076 @subsubheading Prometheus Node Exporter Service
19078 @cindex prometheus-node-exporter
19079 The Prometheus ``node exporter'' makes hardware and operating system statistics
19080 provided by the Linux kernel available for the Prometheus monitoring system.
19081 This service should be deployed on all physical nodes and virtual machines,
19082 where monitoring these statistics is desirable.
19084 @defvar {Scheme variable} prometheus-node-exporter-service-type
19085 This is the service type for the
19086 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
19087 service, its value must be a @code{prometheus-node-exporter-configuration}
19088 record as in this example:
19091 (service prometheus-node-exporter-service-type
19092 (prometheus-node-exporter-configuration
19093 (web-listen-address ":9100")))
19097 @deftp {Data Type} prometheus-node-exporter-configuration
19098 Data type representing the configuration of @command{node_exporter}.
19101 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
19102 The prometheus-node-exporter package to use.
19104 @item @code{web-listen-address} (default: @code{":9100"})
19105 Bind the web interface to the specified address.
19110 @subsubheading Zabbix server
19111 @cindex zabbix zabbix-server
19112 Zabbix provides monitoring metrics, among others network utilization, CPU load
19113 and disk space consumption:
19116 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
19117 @item Auto-discovery of servers and network devices and interfaces.
19118 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
19119 @item Distributed monitoring with centralized web administration.
19120 @item Native high performance agents.
19121 @item SLA, and ITIL KPI metrics on reporting.
19122 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
19123 @item Remote command execution through Zabbix proxies.
19126 @c %start of fragment
19128 Available @code{zabbix-server-configuration} fields are:
19130 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
19131 The zabbix-server package.
19135 @deftypevr {@code{zabbix-server-configuration} parameter} string user
19136 User who will run the Zabbix server.
19138 Defaults to @samp{"zabbix"}.
19142 @deftypevr {@code{zabbix-server-configuration} parameter} group group
19143 Group who will run the Zabbix server.
19145 Defaults to @samp{"zabbix"}.
19149 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
19150 Database host name.
19152 Defaults to @samp{"127.0.0.1"}.
19156 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
19159 Defaults to @samp{"zabbix"}.
19163 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
19166 Defaults to @samp{"zabbix"}.
19170 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
19171 Database password. Please, use @code{include-files} with
19172 @code{DBPassword=SECRET} inside a specified file instead.
19174 Defaults to @samp{""}.
19178 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
19181 Defaults to @samp{5432}.
19185 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
19186 Specifies where log messages are written to:
19190 @code{system} - syslog.
19193 @code{file} - file specified with @code{log-file} parameter.
19196 @code{console} - standard output.
19200 Defaults to @samp{""}.
19204 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
19205 Log file name for @code{log-type} @code{file} parameter.
19207 Defaults to @samp{"/var/log/zabbix/server.log"}.
19211 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
19214 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
19218 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
19219 The location of certificate authority (CA) files for SSL server
19220 certificate verification.
19222 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
19226 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
19227 Location of SSL client certificates.
19229 Defaults to @samp{"/etc/ssl/certs"}.
19233 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
19234 Extra options will be appended to Zabbix server configuration file.
19236 Defaults to @samp{""}.
19240 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
19241 You may include individual files or all files in a directory in the
19242 configuration file.
19244 Defaults to @samp{()}.
19248 @c %end of fragment
19250 @subsubheading Zabbix agent
19251 @cindex zabbix zabbix-agent
19253 Zabbix agent gathers information for Zabbix server.
19255 @c %start of fragment
19257 Available @code{zabbix-agent-configuration} fields are:
19259 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
19260 The zabbix-agent package.
19264 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
19265 User who will run the Zabbix agent.
19267 Defaults to @samp{"zabbix"}.
19271 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
19272 Group who will run the Zabbix agent.
19274 Defaults to @samp{"zabbix"}.
19278 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
19279 Unique, case sensitive hostname which is required for active checks and
19280 must match hostname as configured on the server.
19282 Defaults to @samp{"Zabbix server"}.
19286 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
19287 Specifies where log messages are written to:
19291 @code{system} - syslog.
19294 @code{file} - file specified with @code{log-file} parameter.
19297 @code{console} - standard output.
19301 Defaults to @samp{""}.
19305 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
19306 Log file name for @code{log-type} @code{file} parameter.
19308 Defaults to @samp{"/var/log/zabbix/agent.log"}.
19312 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
19315 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
19319 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
19320 List of IP addresses, optionally in CIDR notation, or hostnames of
19321 Zabbix servers and Zabbix proxies. Incoming connections will be
19322 accepted only from the hosts listed here.
19324 Defaults to @samp{("127.0.0.1")}.
19328 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
19329 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
19330 proxies for active checks. If port is not specified, default port is
19331 used. If this parameter is not specified, active checks are disabled.
19333 Defaults to @samp{("127.0.0.1")}.
19337 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
19338 Extra options will be appended to Zabbix server configuration file.
19340 Defaults to @samp{""}.
19344 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
19345 You may include individual files or all files in a directory in the
19346 configuration file.
19348 Defaults to @samp{()}.
19352 @c %end of fragment
19354 @subsubheading Zabbix front-end
19355 @cindex zabbix zabbix-front-end
19357 This service provides a WEB interface to Zabbix server.
19359 @c %start of fragment
19361 Available @code{zabbix-front-end-configuration} fields are:
19363 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
19364 NGINX configuration.
19368 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
19369 Database host name.
19371 Defaults to @samp{"localhost"}.
19375 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
19378 Defaults to @samp{5432}.
19382 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
19385 Defaults to @samp{"zabbix"}.
19389 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
19392 Defaults to @samp{"zabbix"}.
19396 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
19397 Database password. Please, use @code{db-secret-file} instead.
19399 Defaults to @samp{""}.
19403 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
19404 Secret file which will be appended to @file{zabbix.conf.php} file. This
19405 file contains credentials for use by Zabbix front-end. You are expected
19406 to create it manually.
19408 Defaults to @samp{""}.
19412 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
19413 Zabbix server hostname.
19415 Defaults to @samp{"localhost"}.
19419 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
19420 Zabbix server port.
19422 Defaults to @samp{10051}.
19427 @c %end of fragment
19429 @node Kerberos Services
19430 @subsection Kerberos Services
19433 The @code{(gnu services kerberos)} module provides services relating to
19434 the authentication protocol @dfn{Kerberos}.
19436 @subsubheading Krb5 Service
19438 Programs using a Kerberos client library normally
19439 expect a configuration file in @file{/etc/krb5.conf}.
19440 This service generates such a file from a definition provided in the
19441 operating system declaration.
19442 It does not cause any daemon to be started.
19444 No ``keytab'' files are provided by this service---you must explicitly create them.
19445 This service is known to work with the MIT client library, @code{mit-krb5}.
19446 Other implementations have not been tested.
19448 @defvr {Scheme Variable} krb5-service-type
19449 A service type for Kerberos 5 clients.
19453 Here is an example of its use:
19455 (service krb5-service-type
19456 (krb5-configuration
19457 (default-realm "EXAMPLE.COM")
19458 (allow-weak-crypto? #t)
19461 (name "EXAMPLE.COM")
19462 (admin-server "groucho.example.com")
19463 (kdc "karl.example.com"))
19466 (admin-server "kerb-admin.argrx.edu")
19467 (kdc "keys.argrx.edu"))))))
19471 This example provides a Kerberos@tie{}5 client configuration which:
19473 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
19474 of which have distinct administration servers and key distribution centers;
19475 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
19476 specified by clients;
19477 @item Accepts services which only support encryption types known to be weak.
19480 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
19481 Only the most commonly used ones are described here.
19482 For a full list, and more detailed explanation of each, see the MIT
19483 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
19487 @deftp {Data Type} krb5-realm
19488 @cindex realm, kerberos
19491 This field is a string identifying the name of the realm.
19492 A common convention is to use the fully qualified DNS name of your organization,
19493 converted to upper case.
19495 @item @code{admin-server}
19496 This field is a string identifying the host where the administration server is
19500 This field is a string identifying the key distribution center
19505 @deftp {Data Type} krb5-configuration
19508 @item @code{allow-weak-crypto?} (default: @code{#f})
19509 If this flag is @code{#t} then services which only offer encryption algorithms
19510 known to be weak will be accepted.
19512 @item @code{default-realm} (default: @code{#f})
19513 This field should be a string identifying the default Kerberos
19514 realm for the client.
19515 You should set this field to the name of your Kerberos realm.
19516 If this value is @code{#f}
19517 then a realm must be specified with every Kerberos principal when invoking programs
19518 such as @command{kinit}.
19520 @item @code{realms}
19521 This should be a non-empty list of @code{krb5-realm} objects, which clients may
19523 Normally, one of them will have a @code{name} field matching the @code{default-realm}
19529 @subsubheading PAM krb5 Service
19532 The @code{pam-krb5} service allows for login authentication and password
19533 management via Kerberos.
19534 You will need this service if you want PAM enabled applications to authenticate
19535 users using Kerberos.
19537 @defvr {Scheme Variable} pam-krb5-service-type
19538 A service type for the Kerberos 5 PAM module.
19541 @deftp {Data Type} pam-krb5-configuration
19542 Data type representing the configuration of the Kerberos 5 PAM module.
19543 This type has the following parameters:
19545 @item @code{pam-krb5} (default: @code{pam-krb5})
19546 The pam-krb5 package to use.
19548 @item @code{minimum-uid} (default: @code{1000})
19549 The smallest user ID for which Kerberos authentications should be attempted.
19550 Local accounts with lower values will silently fail to authenticate.
19555 @node LDAP Services
19556 @subsection LDAP Services
19558 @cindex nslcd, LDAP service
19560 The @code{(gnu services authentication)} module provides the
19561 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
19562 server. In addition to configuring the service itself, you may want to add
19563 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
19564 Switch} for detailed information.
19566 Here is a simple operating system declaration with a default configuration of
19567 the @code{nslcd-service-type} and a Name Service Switch configuration that
19568 consults the @code{ldap} name service last:
19571 (use-service-modules authentication)
19572 (use-modules (gnu system nss))
19578 (service nslcd-service-type)
19579 (service dhcp-client-service-type)
19581 (name-service-switch
19582 (let ((services (list (name-service (name "db"))
19583 (name-service (name "files"))
19584 (name-service (name "ldap")))))
19585 (name-service-switch
19586 (inherit %mdns-host-lookup-nss)
19587 (password services)
19590 (netgroup services)
19591 (gshadow services)))))
19594 @c %start of generated documentation for nslcd-configuration
19596 Available @code{nslcd-configuration} fields are:
19598 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
19599 The @code{nss-pam-ldapd} package to use.
19603 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
19604 The number of threads to start that can handle requests and perform LDAP
19605 queries. Each thread opens a separate connection to the LDAP server.
19606 The default is to start 5 threads.
19608 Defaults to @samp{disabled}.
19612 @deftypevr {@code{nslcd-configuration} parameter} string uid
19613 This specifies the user id with which the daemon should be run.
19615 Defaults to @samp{"nslcd"}.
19619 @deftypevr {@code{nslcd-configuration} parameter} string gid
19620 This specifies the group id with which the daemon should be run.
19622 Defaults to @samp{"nslcd"}.
19626 @deftypevr {@code{nslcd-configuration} parameter} log-option log
19627 This option controls the way logging is done via a list containing
19628 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
19629 or "syslog", or an absolute file name. The LEVEL argument is optional
19630 and specifies the log level. The log level may be one of the following
19631 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
19632 messages with the specified log level or higher are logged.
19634 Defaults to @samp{("/var/log/nslcd" info)}.
19638 @deftypevr {@code{nslcd-configuration} parameter} list uri
19639 The list of LDAP server URIs. Normally, only the first server will be
19640 used with the following servers as fall-back.
19642 Defaults to @samp{("ldap://localhost:389/")}.
19646 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
19647 The version of the LDAP protocol to use. The default is to use the
19648 maximum version supported by the LDAP library.
19650 Defaults to @samp{disabled}.
19654 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
19655 Specifies the distinguished name with which to bind to the directory
19656 server for lookups. The default is to bind anonymously.
19658 Defaults to @samp{disabled}.
19662 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
19663 Specifies the credentials with which to bind. This option is only
19664 applicable when used with binddn.
19666 Defaults to @samp{disabled}.
19670 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
19671 Specifies the distinguished name to use when the root user tries to
19672 modify a user's password using the PAM module.
19674 Defaults to @samp{disabled}.
19678 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
19679 Specifies the credentials with which to bind if the root user tries to
19680 change a user's password. This option is only applicable when used with
19683 Defaults to @samp{disabled}.
19687 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
19688 Specifies the SASL mechanism to be used when performing SASL
19691 Defaults to @samp{disabled}.
19695 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
19696 Specifies the SASL realm to be used when performing SASL authentication.
19698 Defaults to @samp{disabled}.
19702 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
19703 Specifies the authentication identity to be used when performing SASL
19706 Defaults to @samp{disabled}.
19710 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
19711 Specifies the authorization identity to be used when performing SASL
19714 Defaults to @samp{disabled}.
19718 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
19719 Determines whether the LDAP server host name should be canonicalised. If
19720 this is enabled the LDAP library will do a reverse host name lookup. By
19721 default, it is left up to the LDAP library whether this check is
19724 Defaults to @samp{disabled}.
19728 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
19729 Set the name for the GSS-API Kerberos credentials cache.
19731 Defaults to @samp{disabled}.
19735 @deftypevr {@code{nslcd-configuration} parameter} string base
19736 The directory search base.
19738 Defaults to @samp{"dc=example,dc=com"}.
19742 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
19743 Specifies the search scope (subtree, onelevel, base or children). The
19744 default scope is subtree; base scope is almost never useful for name
19745 service lookups; children scope is not supported on all servers.
19747 Defaults to @samp{(subtree)}.
19751 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
19752 Specifies the policy for dereferencing aliases. The default policy is
19753 to never dereference aliases.
19755 Defaults to @samp{disabled}.
19759 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
19760 Specifies whether automatic referral chasing should be enabled. The
19761 default behaviour is to chase referrals.
19763 Defaults to @samp{disabled}.
19767 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
19768 This option allows for custom attributes to be looked up instead of the
19769 default RFC 2307 attributes. It is a list of maps, each consisting of
19770 the name of a map, the RFC 2307 attribute to match and the query
19771 expression for the attribute as it is available in the directory.
19773 Defaults to @samp{()}.
19777 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
19778 A list of filters consisting of the name of a map to which the filter
19779 applies and an LDAP search filter expression.
19781 Defaults to @samp{()}.
19785 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
19786 Specifies the time limit in seconds to use when connecting to the
19787 directory server. The default value is 10 seconds.
19789 Defaults to @samp{disabled}.
19793 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
19794 Specifies the time limit (in seconds) to wait for a response from the
19795 LDAP server. A value of zero, which is the default, is to wait
19796 indefinitely for searches to be completed.
19798 Defaults to @samp{disabled}.
19802 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
19803 Specifies the period if inactivity (in seconds) after which the con‐
19804 nection to the LDAP server will be closed. The default is not to time
19807 Defaults to @samp{disabled}.
19811 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
19812 Specifies the number of seconds to sleep when connecting to all LDAP
19813 servers fails. By default one second is waited between the first
19814 failure and the first retry.
19816 Defaults to @samp{disabled}.
19820 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
19821 Specifies the time after which the LDAP server is considered to be
19822 permanently unavailable. Once this time is reached retries will be done
19823 only once per this time period. The default value is 10 seconds.
19825 Defaults to @samp{disabled}.
19829 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
19830 Specifies whether to use SSL/TLS or not (the default is not to). If
19831 'start-tls is specified then StartTLS is used rather than raw LDAP over
19834 Defaults to @samp{disabled}.
19838 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
19839 Specifies what checks to perform on a server-supplied certificate. The
19840 meaning of the values is described in the ldap.conf(5) manual page.
19842 Defaults to @samp{disabled}.
19846 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
19847 Specifies the directory containing X.509 certificates for peer authen‐
19848 tication. This parameter is ignored when using GnuTLS.
19850 Defaults to @samp{disabled}.
19854 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
19855 Specifies the path to the X.509 certificate for peer authentication.
19857 Defaults to @samp{disabled}.
19861 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
19862 Specifies the path to an entropy source. This parameter is ignored when
19865 Defaults to @samp{disabled}.
19869 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
19870 Specifies the ciphers to use for TLS as a string.
19872 Defaults to @samp{disabled}.
19876 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
19877 Specifies the path to the file containing the local certificate for
19878 client TLS authentication.
19880 Defaults to @samp{disabled}.
19884 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
19885 Specifies the path to the file containing the private key for client TLS
19888 Defaults to @samp{disabled}.
19892 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
19893 Set this to a number greater than 0 to request paged results from the
19894 LDAP server in accordance with RFC2696. The default (0) is to not
19895 request paged results.
19897 Defaults to @samp{disabled}.
19901 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
19902 This option prevents group membership lookups through LDAP for the
19903 specified users. Alternatively, the value 'all-local may be used. With
19904 that value nslcd builds a full list of non-LDAP users on startup.
19906 Defaults to @samp{disabled}.
19910 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
19911 This option ensures that LDAP users with a numeric user id lower than
19912 the specified value are ignored.
19914 Defaults to @samp{disabled}.
19918 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
19919 This option specifies an offset that is added to all LDAP numeric user
19920 ids. This can be used to avoid user id collisions with local users.
19922 Defaults to @samp{disabled}.
19926 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
19927 This option specifies an offset that is added to all LDAP numeric group
19928 ids. This can be used to avoid user id collisions with local groups.
19930 Defaults to @samp{disabled}.
19934 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
19935 If this option is set, the member attribute of a group may point to
19936 another group. Members of nested groups are also returned in the higher
19937 level group and parent groups are returned when finding groups for a
19938 specific user. The default is not to perform extra searches for nested
19941 Defaults to @samp{disabled}.
19945 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
19946 If this option is set, the group member list is not retrieved when
19947 looking up groups. Lookups for finding which groups a user belongs to
19948 will remain functional so the user will likely still get the correct
19949 groups assigned on login.
19951 Defaults to @samp{disabled}.
19955 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
19956 If this option is set, functions which cause all user/group entries to
19957 be loaded from the directory will not succeed in doing so. This can
19958 dramatically reduce LDAP server load in situations where there are a
19959 great number of users and/or groups. This option is not recommended for
19960 most configurations.
19962 Defaults to @samp{disabled}.
19966 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
19967 This option can be used to specify how user and group names are verified
19968 within the system. This pattern is used to check all user and group
19969 names that are requested and returned from LDAP.
19971 Defaults to @samp{disabled}.
19975 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
19976 This specifies whether or not to perform searches using case-insensitive
19977 matching. Enabling this could open up the system to authorization
19978 bypass vulnerabilities and introduce nscd cache poisoning
19979 vulnerabilities which allow denial of service.
19981 Defaults to @samp{disabled}.
19985 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
19986 This option specifies whether password policy controls are requested and
19987 handled from the LDAP server when performing user authentication.
19989 Defaults to @samp{disabled}.
19993 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
19994 By default nslcd performs an LDAP search with the user's credentials
19995 after BIND (authentication) to ensure that the BIND operation was
19996 successful. The default search is a simple check to see if the user's
19997 DN exists. A search filter can be specified that will be used instead.
19998 It should return at least one entry.
20000 Defaults to @samp{disabled}.
20004 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
20005 This option allows flexible fine tuning of the authorisation check that
20006 should be performed. The search filter specified is executed and if any
20007 entries match, access is granted, otherwise access is denied.
20009 Defaults to @samp{disabled}.
20013 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
20014 If this option is set password modification using pam_ldap will be
20015 denied and the specified message will be presented to the user instead.
20016 The message can be used to direct the user to an alternative means of
20017 changing their password.
20019 Defaults to @samp{disabled}.
20023 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
20024 List of pam service names for which LDAP authentication should suffice.
20026 Defaults to @samp{()}.
20030 @c %end of generated documentation for nslcd-configuration
20034 @subsection Web Services
20039 The @code{(gnu services web)} module provides the Apache HTTP Server,
20040 the nginx web server, and also a fastcgi wrapper daemon.
20042 @subsubheading Apache HTTP Server
20044 @deffn {Scheme Variable} httpd-service-type
20045 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
20046 (@dfn{httpd}). The value for this service type is a
20047 @code{httpd-configuration} record.
20049 A simple example configuration is given below.
20052 (service httpd-service-type
20053 (httpd-configuration
20056 (server-name "www.example.com")
20057 (document-root "/srv/http/www.example.com")))))
20060 Other services can also extend the @code{httpd-service-type} to add to
20064 (simple-service 'www.example.com-server httpd-service-type
20068 (list (string-join '("ServerName www.example.com"
20069 "DocumentRoot /srv/http/www.example.com")
20074 The details for the @code{httpd-configuration}, @code{httpd-module},
20075 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
20078 @deffn {Data Type} httpd-configuration
20079 This data type represents the configuration for the httpd service.
20082 @item @code{package} (default: @code{httpd})
20083 The httpd package to use.
20085 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20086 The pid file used by the shepherd-service.
20088 @item @code{config} (default: @code{(httpd-config-file)})
20089 The configuration file to use with the httpd service. The default value
20090 is a @code{httpd-config-file} record, but this can also be a different
20091 G-expression that generates a file, for example a @code{plain-file}. A
20092 file outside of the store can also be specified through a string.
20097 @deffn {Data Type} httpd-module
20098 This data type represents a module for the httpd service.
20102 The name of the module.
20105 The file for the module. This can be relative to the httpd package being
20106 used, the absolute location of a file, or a G-expression for a file
20107 within the store, for example @code{(file-append mod-wsgi
20108 "/modules/mod_wsgi.so")}.
20113 @defvr {Scheme Variable} %default-httpd-modules
20114 A default list of @code{httpd-module} objects.
20117 @deffn {Data Type} httpd-config-file
20118 This data type represents a configuration file for the httpd service.
20121 @item @code{modules} (default: @code{%default-httpd-modules})
20122 The modules to load. Additional modules can be added here, or loaded by
20123 additional configuration.
20125 For example, in order to handle requests for PHP files, you can use Apache’s
20126 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
20129 (service httpd-service-type
20130 (httpd-configuration
20135 (name "proxy_module")
20136 (file "modules/mod_proxy.so"))
20138 (name "proxy_fcgi_module")
20139 (file "modules/mod_proxy_fcgi.so"))
20140 %default-httpd-modules))
20141 (extra-config (list "\
20142 <FilesMatch \\.php$>
20143 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
20144 </FilesMatch>"))))))
20145 (service php-fpm-service-type
20146 (php-fpm-configuration
20147 (socket "/var/run/php-fpm.sock")
20148 (socket-group "httpd")))
20151 @item @code{server-root} (default: @code{httpd})
20152 The @code{ServerRoot} in the configuration file, defaults to the httpd
20153 package. Directives including @code{Include} and @code{LoadModule} are
20154 taken as relative to the server root.
20156 @item @code{server-name} (default: @code{#f})
20157 The @code{ServerName} in the configuration file, used to specify the
20158 request scheme, hostname and port that the server uses to identify
20161 This doesn't need to be set in the server config, and can be specified
20162 in virtual hosts. The default is @code{#f} to not specify a
20165 @item @code{document-root} (default: @code{"/srv/http"})
20166 The @code{DocumentRoot} from which files will be served.
20168 @item @code{listen} (default: @code{'("80")})
20169 The list of values for the @code{Listen} directives in the config
20170 file. The value should be a list of strings, when each string can
20171 specify the port number to listen on, and optionally the IP address and
20174 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20175 The @code{PidFile} to use. This should match the @code{pid-file} set in
20176 the @code{httpd-configuration} so that the Shepherd service is
20177 configured correctly.
20179 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
20180 The @code{ErrorLog} to which the server will log errors.
20182 @item @code{user} (default: @code{"httpd"})
20183 The @code{User} which the server will answer requests as.
20185 @item @code{group} (default: @code{"httpd"})
20186 The @code{Group} which the server will answer requests as.
20188 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
20189 A flat list of strings and G-expressions which will be added to the end
20190 of the configuration file.
20192 Any values which the service is extended with will be appended to this
20198 @deffn {Data Type} httpd-virtualhost
20199 This data type represents a virtualhost configuration block for the httpd service.
20201 These should be added to the extra-config for the httpd-service.
20204 (simple-service 'www.example.com-server httpd-service-type
20208 (list (string-join '("ServerName www.example.com"
20209 "DocumentRoot /srv/http/www.example.com")
20214 @item @code{addresses-and-ports}
20215 The addresses and ports for the @code{VirtualHost} directive.
20217 @item @code{contents}
20218 The contents of the @code{VirtualHost} directive, this should be a list
20219 of strings and G-expressions.
20224 @subsubheading NGINX
20226 @deffn {Scheme Variable} nginx-service-type
20227 Service type for the @uref{https://nginx.org/,NGinx} web server. The
20228 value for this service type is a @code{<nginx-configuration>} record.
20230 A simple example configuration is given below.
20233 (service nginx-service-type
20234 (nginx-configuration
20236 (list (nginx-server-configuration
20237 (server-name '("www.example.com"))
20238 (root "/srv/http/www.example.com"))))))
20241 In addition to adding server blocks to the service configuration
20242 directly, this service can be extended by other services to add server
20243 blocks, as in this example:
20246 (simple-service 'my-extra-server nginx-service-type
20247 (list (nginx-server-configuration
20248 (root "/srv/http/extra-website")
20249 (try-files (list "$uri" "$uri/index.html")))))
20253 At startup, @command{nginx} has not yet read its configuration file, so
20254 it uses a default file to log error messages. If it fails to load its
20255 configuration file, that is where error messages are logged. After the
20256 configuration file is loaded, the default error log file changes as per
20257 configuration. In our case, startup error messages can be found in
20258 @file{/var/run/nginx/logs/error.log}, and after configuration in
20259 @file{/var/log/nginx/error.log}. The second location can be changed
20260 with the @var{log-directory} configuration option.
20262 @deffn {Data Type} nginx-configuration
20263 This data type represents the configuration for NGinx. Some
20264 configuration can be done through this and the other provided record
20265 types, or alternatively, a config file can be provided.
20268 @item @code{nginx} (default: @code{nginx})
20269 The nginx package to use.
20271 @item @code{log-directory} (default: @code{"/var/log/nginx"})
20272 The directory to which NGinx will write log files.
20274 @item @code{run-directory} (default: @code{"/var/run/nginx"})
20275 The directory in which NGinx will create a pid file, and write temporary
20278 @item @code{server-blocks} (default: @code{'()})
20279 A list of @dfn{server blocks} to create in the generated configuration
20280 file, the elements should be of type
20281 @code{<nginx-server-configuration>}.
20283 The following example would setup NGinx to serve @code{www.example.com}
20284 from the @code{/srv/http/www.example.com} directory, without using
20287 (service nginx-service-type
20288 (nginx-configuration
20290 (list (nginx-server-configuration
20291 (server-name '("www.example.com"))
20292 (root "/srv/http/www.example.com"))))))
20295 @item @code{upstream-blocks} (default: @code{'()})
20296 A list of @dfn{upstream blocks} to create in the generated configuration
20297 file, the elements should be of type
20298 @code{<nginx-upstream-configuration>}.
20300 Configuring upstreams through the @code{upstream-blocks} can be useful
20301 when combined with @code{locations} in the
20302 @code{<nginx-server-configuration>} records. The following example
20303 creates a server configuration with one location configuration, that
20304 will proxy requests to a upstream configuration, which will handle
20305 requests with two servers.
20310 (nginx-configuration
20312 (list (nginx-server-configuration
20313 (server-name '("www.example.com"))
20314 (root "/srv/http/www.example.com")
20317 (nginx-location-configuration
20319 (body '("proxy_pass http://server-proxy;"))))))))
20321 (list (nginx-upstream-configuration
20322 (name "server-proxy")
20323 (servers (list "server1.example.com"
20324 "server2.example.com")))))))
20327 @item @code{file} (default: @code{#f})
20328 If a configuration @var{file} is provided, this will be used, rather than
20329 generating a configuration file from the provided @code{log-directory},
20330 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
20331 proper operation, these arguments should match what is in @var{file} to ensure
20332 that the directories are created when the service is activated.
20334 This can be useful if you have an existing configuration file, or it's
20335 not possible to do what is required through the other parts of the
20336 nginx-configuration record.
20338 @item @code{server-names-hash-bucket-size} (default: @code{#f})
20339 Bucket size for the server names hash tables, defaults to @code{#f} to
20340 use the size of the processors cache line.
20342 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
20343 Maximum bucket size for the server names hash tables.
20345 @item @code{modules} (default: @code{'()})
20346 List of nginx dynamic modules to load. This should be a list of file
20347 names of loadable modules, as in this example:
20352 (file-append nginx-accept-language-module "\
20353 /etc/nginx/modules/ngx_http_accept_language_module.so")))
20356 @item @code{global-directives} (default: @code{'((events . ()))})
20357 Association list of global directives for the top level of the nginx
20358 configuration. Values may themselves be association lists.
20362 `((worker_processes . 16)
20364 (events . ((worker_connections . 1024)))))
20367 @item @code{extra-content} (default: @code{""})
20368 Extra content for the @code{http} block. Should be string or a string
20369 valued G-expression.
20374 @deftp {Data Type} nginx-server-configuration
20375 Data type representing the configuration of an nginx server block.
20376 This type has the following parameters:
20379 @item @code{listen} (default: @code{'("80" "443 ssl")})
20380 Each @code{listen} directive sets the address and port for IP, or the
20381 path for a UNIX-domain socket on which the server will accept requests.
20382 Both address and port, or only address or only port can be specified.
20383 An address may also be a hostname, for example:
20386 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
20389 @item @code{server-name} (default: @code{(list 'default)})
20390 A list of server names this server represents. @code{'default} represents the
20391 default server for connections matching no other server.
20393 @item @code{root} (default: @code{"/srv/http"})
20394 Root of the website nginx will serve.
20396 @item @code{locations} (default: @code{'()})
20397 A list of @dfn{nginx-location-configuration} or
20398 @dfn{nginx-named-location-configuration} records to use within this
20401 @item @code{index} (default: @code{(list "index.html")})
20402 Index files to look for when clients ask for a directory. If it cannot be found,
20403 Nginx will send the list of files in the directory.
20405 @item @code{try-files} (default: @code{'()})
20406 A list of files whose existence is checked in the specified order.
20407 @code{nginx} will use the first file it finds to process the request.
20409 @item @code{ssl-certificate} (default: @code{#f})
20410 Where to find the certificate for secure connections. Set it to @code{#f} if
20411 you don't have a certificate or you don't want to use HTTPS.
20413 @item @code{ssl-certificate-key} (default: @code{#f})
20414 Where to find the private key for secure connections. Set it to @code{#f} if
20415 you don't have a key or you don't want to use HTTPS.
20417 @item @code{server-tokens?} (default: @code{#f})
20418 Whether the server should add its configuration to response.
20420 @item @code{raw-content} (default: @code{'()})
20421 A list of raw lines added to the server block.
20426 @deftp {Data Type} nginx-upstream-configuration
20427 Data type representing the configuration of an nginx @code{upstream}
20428 block. This type has the following parameters:
20432 Name for this group of servers.
20434 @item @code{servers}
20435 Specify the addresses of the servers in the group. The address can be
20436 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
20437 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
20438 prefix @samp{unix:}. For addresses using an IP address or domain name,
20439 the default port is 80, and a different port can be specified
20445 @deftp {Data Type} nginx-location-configuration
20446 Data type representing the configuration of an nginx @code{location}
20447 block. This type has the following parameters:
20451 URI which this location block matches.
20453 @anchor{nginx-location-configuration body}
20455 Body of the location block, specified as a list of strings. This can contain
20457 configuration directives. For example, to pass requests to a upstream
20458 server group defined using an @code{nginx-upstream-configuration} block,
20459 the following directive would be specified in the body @samp{(list "proxy_pass
20460 http://upstream-name;")}.
20465 @deftp {Data Type} nginx-named-location-configuration
20466 Data type representing the configuration of an nginx named location
20467 block. Named location blocks are used for request redirection, and not
20468 used for regular request processing. This type has the following
20473 Name to identify this location block.
20476 @xref{nginx-location-configuration body}, as the body for named location
20477 blocks can be used in a similar way to the
20478 @code{nginx-location-configuration body}. One restriction is that the
20479 body of a named location block cannot contain location blocks.
20484 @subsubheading Varnish Cache
20486 Varnish is a fast cache server that sits in between web applications
20487 and end users. It proxies requests from clients and caches the
20488 accessed URLs such that multiple requests for the same resource only
20489 creates one request to the back-end.
20491 @defvr {Scheme Variable} varnish-service-type
20492 Service type for the Varnish daemon.
20495 @deftp {Data Type} varnish-configuration
20496 Data type representing the @code{varnish} service configuration.
20497 This type has the following parameters:
20500 @item @code{package} (default: @code{varnish})
20501 The Varnish package to use.
20503 @item @code{name} (default: @code{"default"})
20504 A name for this Varnish instance. Varnish will create a directory in
20505 @file{/var/varnish/} with this name and keep temporary files there. If
20506 the name starts with a forward slash, it is interpreted as an absolute
20509 Pass the @code{-n} argument to other Varnish programs to connect to the
20510 named instance, e.g.@: @command{varnishncsa -n default}.
20512 @item @code{backend} (default: @code{"localhost:8080"})
20513 The backend to use. This option has no effect if @code{vcl} is set.
20515 @item @code{vcl} (default: #f)
20516 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
20517 is @code{#f}, Varnish will proxy @code{backend} using the default
20518 configuration. Otherwise this must be a file-like object with valid
20521 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
20522 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
20523 can do something along these lines:
20526 (define %gnu-mirror
20527 (plain-file "gnu.vcl"
20529 backend gnu @{ .host = \"www.gnu.org\"; @}"))
20533 (services (cons (service varnish-service-type
20534 (varnish-configuration
20536 (vcl %gnu-mirror)))
20540 The configuration of an already running Varnish instance can be inspected
20541 and changed using the @command{varnishadm} program.
20543 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
20544 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
20545 comprehensive documentation on Varnish and its configuration language.
20547 @item @code{listen} (default: @code{'("localhost:80")})
20548 List of addresses Varnish will listen on.
20550 @item @code{storage} (default: @code{'("malloc,128m")})
20551 List of storage backends that will be available in VCL.
20553 @item @code{parameters} (default: @code{'()})
20554 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
20556 @item @code{extra-options} (default: @code{'()})
20557 Additional arguments to pass to the @command{varnishd} process.
20562 @subsubheading Patchwork
20564 Patchwork is a patch tracking system. It can collect patches sent to a
20565 mailing list, and display them in a web interface.
20567 @defvr {Scheme Variable} patchwork-service-type
20568 Service type for Patchwork.
20571 The following example is an example of a minimal service for Patchwork, for
20572 the @code{patchwork.example.com} domain.
20575 (service patchwork-service-type
20576 (patchwork-configuration
20577 (domain "patchwork.example.com")
20579 (patchwork-settings-module
20580 (allowed-hosts (list domain))
20581 (default-from-email "patchwork@@patchwork.example.com")))
20582 (getmail-retriever-config
20583 (getmail-retriever-configuration
20584 (type "SimpleIMAPSSLRetriever")
20585 (server "imap.example.com")
20587 (username "patchwork")
20589 (list (file-append coreutils "/bin/cat")
20590 "/etc/getmail-patchwork-imap-password"))
20592 '((mailboxes . ("Patches"))))))))
20596 There are three records for configuring the Patchwork service. The
20597 @code{<patchwork-configuration>} relates to the configuration for Patchwork
20598 within the HTTPD service.
20600 The @code{settings-module} field within the @code{<patchwork-configuration>}
20601 record can be populated with the @code{<patchwork-settings-module>} record,
20602 which describes a settings module that is generated within the Guix store.
20604 For the @code{database-configuration} field within the
20605 @code{<patchwork-settings-module>}, the
20606 @code{<patchwork-database-configuration>} must be used.
20608 @deftp {Data Type} patchwork-configuration
20609 Data type representing the Patchwork service configuration. This type has the
20610 following parameters:
20613 @item @code{patchwork} (default: @code{patchwork})
20614 The Patchwork package to use.
20616 @item @code{domain}
20617 The domain to use for Patchwork, this is used in the HTTPD service virtual
20620 @item @code{settings-module}
20621 The settings module to use for Patchwork. As a Django application, Patchwork
20622 is configured with a Python module containing the settings. This can either be
20623 an instance of the @code{<patchwork-settings-module>} record, any other record
20624 that represents the settings in the store, or a directory outside of the
20627 @item @code{static-path} (default: @code{"/static/"})
20628 The path under which the HTTPD service should serve the static files.
20630 @item @code{getmail-retriever-config}
20631 The getmail-retriever-configuration record value to use with
20632 Patchwork. Getmail will be configured with this value, the messages will be
20633 delivered to Patchwork.
20638 @deftp {Data Type} patchwork-settings-module
20639 Data type representing a settings module for Patchwork. Some of these
20640 settings relate directly to Patchwork, but others relate to Django, the web
20641 framework used by Patchwork, or the Django Rest Framework library. This type
20642 has the following parameters:
20645 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
20646 The database connection settings used for Patchwork. See the
20647 @code{<patchwork-database-configuration>} record type for more information.
20649 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
20650 Patchwork, as a Django web application uses a secret key for cryptographically
20651 signing values. This file should contain a unique unpredictable value.
20653 If this file does not exist, it will be created and populated with a random
20654 value by the patchwork-setup shepherd service.
20656 This setting relates to Django.
20658 @item @code{allowed-hosts}
20659 A list of valid hosts for this Patchwork service. This should at least include
20660 the domain specified in the @code{<patchwork-configuration>} record.
20662 This is a Django setting.
20664 @item @code{default-from-email}
20665 The email address from which Patchwork should send email by default.
20667 This is a Patchwork setting.
20669 @item @code{static-url} (default: @code{#f})
20670 The URL to use when serving static assets. It can be part of a URL, or a full
20671 URL, but must end in a @code{/}.
20673 If the default value is used, the @code{static-path} value from the
20674 @code{<patchwork-configuration>} record will be used.
20676 This is a Django setting.
20678 @item @code{admins} (default: @code{'()})
20679 Email addresses to send the details of errors that occur. Each value should
20680 be a list containing two elements, the name and then the email address.
20682 This is a Django setting.
20684 @item @code{debug?} (default: @code{#f})
20685 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
20686 messages will be shown.
20688 This is a Django setting.
20690 @item @code{enable-rest-api?} (default: @code{#t})
20691 Whether to enable the Patchwork REST API.
20693 This is a Patchwork setting.
20695 @item @code{enable-xmlrpc?} (default: @code{#t})
20696 Whether to enable the XML RPC API.
20698 This is a Patchwork setting.
20700 @item @code{force-https-links?} (default: @code{#t})
20701 Whether to use HTTPS links on Patchwork pages.
20703 This is a Patchwork setting.
20705 @item @code{extra-settings} (default: @code{""})
20706 Extra code to place at the end of the Patchwork settings module.
20711 @deftp {Data Type} patchwork-database-configuration
20712 Data type representing the database configuration for Patchwork.
20715 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
20716 The database engine to use.
20718 @item @code{name} (default: @code{"patchwork"})
20719 The name of the database to use.
20721 @item @code{user} (default: @code{"httpd"})
20722 The user to connect to the database as.
20724 @item @code{password} (default: @code{""})
20725 The password to use when connecting to the database.
20727 @item @code{host} (default: @code{""})
20728 The host to make the database connection to.
20730 @item @code{port} (default: @code{""})
20731 The port on which to connect to the database.
20736 @subsubheading Mumi
20738 @cindex Mumi, Debbugs Web interface
20739 @cindex Debbugs, Mumi Web interface
20740 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
20741 Web interface to the Debbugs bug tracker, by default for
20742 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
20743 but it also fetches and indexes mail retrieved from Debbugs.
20745 @defvr {Scheme Variable} mumi-service-type
20746 This is the service type for Mumi.
20749 @deftp {Data Type} mumi-configuration
20750 Data type representing the Mumi service configuration. This type has the
20754 @item @code{mumi} (default: @code{mumi})
20755 The Mumi package to use.
20757 @item @code{mailer?} (default: @code{#true})
20758 Whether to enable or disable the mailer component.
20760 @item @code{mumi-configuration-sender}
20761 The email address used as the sender for comments.
20763 @item @code{mumi-configuration-smtp}
20764 A URI to configure the SMTP settings for Mailutils. This could be
20765 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
20766 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
20767 mailutils, GNU@tie{}Mailutils}.
20773 @subsubheading FastCGI
20776 FastCGI is an interface between the front-end and the back-end of a web
20777 service. It is a somewhat legacy facility; new web services should
20778 generally just talk HTTP between the front-end and the back-end.
20779 However there are a number of back-end services such as PHP or the
20780 optimized HTTP Git repository access that use FastCGI, so we have
20781 support for it in Guix.
20783 To use FastCGI, you configure the front-end web server (e.g., nginx) to
20784 dispatch some subset of its requests to the fastcgi backend, which
20785 listens on a local TCP or UNIX socket. There is an intermediary
20786 @code{fcgiwrap} program that sits between the actual backend process and
20787 the web server. The front-end indicates which backend program to run,
20788 passing that information to the @code{fcgiwrap} process.
20790 @defvr {Scheme Variable} fcgiwrap-service-type
20791 A service type for the @code{fcgiwrap} FastCGI proxy.
20794 @deftp {Data Type} fcgiwrap-configuration
20795 Data type representing the configuration of the @code{fcgiwrap} service.
20796 This type has the following parameters:
20798 @item @code{package} (default: @code{fcgiwrap})
20799 The fcgiwrap package to use.
20801 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
20802 The socket on which the @code{fcgiwrap} process should listen, as a
20803 string. Valid @var{socket} values include
20804 @code{unix:@var{/path/to/unix/socket}},
20805 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
20806 @code{tcp6:[@var{ipv6_addr}]:port}.
20808 @item @code{user} (default: @code{fcgiwrap})
20809 @itemx @code{group} (default: @code{fcgiwrap})
20810 The user and group names, as strings, under which to run the
20811 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
20812 the user asks for the specific user or group names @code{fcgiwrap} that
20813 the corresponding user and/or group is present on the system.
20815 It is possible to configure a FastCGI-backed web service to pass HTTP
20816 authentication information from the front-end to the back-end, and to
20817 allow @code{fcgiwrap} to run the back-end process as a corresponding
20818 local user. To enable this capability on the back-end, run
20819 @code{fcgiwrap} as the @code{root} user and group. Note that this
20820 capability also has to be configured on the front-end as well.
20825 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
20826 with some additional features useful for sites of any size.
20828 These features include:
20830 @item Adaptive process spawning
20831 @item Basic statistics (similar to Apache's mod_status)
20832 @item Advanced process management with graceful stop/start
20833 @item Ability to start workers with different uid/gid/chroot/environment
20834 and different php.ini (replaces safe_mode)
20835 @item Stdout & stderr logging
20836 @item Emergency restart in case of accidental opcode cache destruction
20837 @item Accelerated upload support
20838 @item Support for a "slowlog"
20839 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
20840 a special function to finish request & flush all data while continuing to do
20841 something time-consuming (video converting, stats processing, etc.)
20843 ...@: and much more.
20845 @defvr {Scheme Variable} php-fpm-service-type
20846 A Service type for @code{php-fpm}.
20849 @deftp {Data Type} php-fpm-configuration
20850 Data Type for php-fpm service configuration.
20852 @item @code{php} (default: @code{php})
20853 The php package to use.
20854 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
20855 The address on which to accept FastCGI requests. Valid syntaxes are:
20857 @item @code{"ip.add.re.ss:port"}
20858 Listen on a TCP socket to a specific address on a specific port.
20859 @item @code{"port"}
20860 Listen on a TCP socket to all addresses on a specific port.
20861 @item @code{"/path/to/unix/socket"}
20862 Listen on a unix socket.
20865 @item @code{user} (default: @code{php-fpm})
20866 User who will own the php worker processes.
20867 @item @code{group} (default: @code{php-fpm})
20868 Group of the worker processes.
20869 @item @code{socket-user} (default: @code{php-fpm})
20870 User who can speak to the php-fpm socket.
20871 @item @code{socket-group} (default: @code{nginx})
20872 Group that can speak to the php-fpm socket.
20873 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
20874 The process id of the php-fpm process is written to this file
20875 once the service has started.
20876 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
20877 Log for the php-fpm master process.
20878 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
20879 Detailed settings for the php-fpm process manager.
20882 @item @code{<php-fpm-dynamic-process-manager-configuration>}
20883 @item @code{<php-fpm-static-process-manager-configuration>}
20884 @item @code{<php-fpm-on-demand-process-manager-configuration>}
20886 @item @code{display-errors} (default @code{#f})
20887 Determines whether php errors and warning should be sent to clients
20888 and displayed in their browsers.
20889 This is useful for local php development, but a security risk for public sites,
20890 as error messages can reveal passwords and personal data.
20891 @item @code{timezone} (default @code{#f})
20892 Specifies @code{php_admin_value[date.timezone]} parameter.
20893 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
20894 This file will log the @code{stderr} outputs of php worker processes.
20895 Can be set to @code{#f} to disable logging.
20896 @item @code{file} (default @code{#f})
20897 An optional override of the whole configuration.
20898 You can use the @code{mixed-text-file} function or an absolute filepath for it.
20902 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
20903 Data Type for the @code{dynamic} php-fpm process manager. With the
20904 @code{dynamic} process manager, spare worker processes are kept around
20905 based on it's configured limits.
20907 @item @code{max-children} (default: @code{5})
20908 Maximum of worker processes.
20909 @item @code{start-servers} (default: @code{2})
20910 How many worker processes should be started on start-up.
20911 @item @code{min-spare-servers} (default: @code{1})
20912 How many spare worker processes should be kept around at minimum.
20913 @item @code{max-spare-servers} (default: @code{3})
20914 How many spare worker processes should be kept around at maximum.
20918 @deftp {Data type} php-fpm-static-process-manager-configuration
20919 Data Type for the @code{static} php-fpm process manager. With the
20920 @code{static} process manager, an unchanging number of worker processes
20923 @item @code{max-children} (default: @code{5})
20924 Maximum of worker processes.
20928 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
20929 Data Type for the @code{on-demand} php-fpm process manager. With the
20930 @code{on-demand} process manager, worker processes are only created as
20933 @item @code{max-children} (default: @code{5})
20934 Maximum of worker processes.
20935 @item @code{process-idle-timeout} (default: @code{10})
20936 The time in seconds after which a process with no requests is killed.
20941 @deffn {Scheme Procedure} nginx-php-location @
20942 [#:nginx-package nginx] @
20943 [socket (string-append "/var/run/php" @
20944 (version-major (package-version php)) @
20946 A helper function to quickly add php to an @code{nginx-server-configuration}.
20949 A simple services setup for nginx with php can look like this:
20951 (services (cons* (service dhcp-client-service-type)
20952 (service php-fpm-service-type)
20953 (service nginx-service-type
20954 (nginx-server-configuration
20955 (server-name '("example.com"))
20956 (root "/srv/http/")
20958 (list (nginx-php-location)))
20960 (ssl-certificate #f)
20961 (ssl-certificate-key #f)))
20965 @cindex cat-avatar-generator
20966 The cat avatar generator is a simple service to demonstrate the use of php-fpm
20967 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
20968 the hash of a user's email address.
20970 @deffn {Scheme Procedure} cat-avatar-generator-service @
20971 [#:cache-dir "/var/cache/cat-avatar-generator"] @
20972 [#:package cat-avatar-generator] @
20973 [#:configuration (nginx-server-configuration)]
20974 Returns an nginx-server-configuration that inherits @code{configuration}. It
20975 extends the nginx configuration to add a server block that serves @code{package},
20976 a version of cat-avatar-generator. During execution, cat-avatar-generator will
20977 be able to use @code{cache-dir} as its cache directory.
20980 A simple setup for cat-avatar-generator can look like this:
20982 (services (cons* (cat-avatar-generator-service
20984 (nginx-server-configuration
20985 (server-name '("example.com"))))
20990 @subsubheading Hpcguix-web
20992 @cindex hpcguix-web
20993 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
20994 program is a customizable web interface to browse Guix packages,
20995 initially designed for users of high-performance computing (HPC)
20998 @defvr {Scheme Variable} hpcguix-web-service-type
20999 The service type for @code{hpcguix-web}.
21002 @deftp {Data Type} hpcguix-web-configuration
21003 Data type for the hpcguix-web service configuration.
21007 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
21008 configuration. The main items available in this spec are:
21011 @item @code{title-prefix} (default: @code{"hpcguix | "})
21012 The page title prefix.
21014 @item @code{guix-command} (default: @code{"guix"})
21015 The @command{guix} command.
21017 @item @code{package-filter-proc} (default: @code{(const #t)})
21018 A procedure specifying how to filter packages that are displayed.
21020 @item @code{package-page-extension-proc} (default: @code{(const '())})
21021 Extension package for @code{hpcguix-web}.
21023 @item @code{menu} (default: @code{'()})
21024 Additional entry in page @code{menu}.
21026 @item @code{channels} (default: @code{%default-channels})
21027 List of channels from which the package list is built (@pxref{Channels}).
21029 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
21030 The expiration time, in seconds, after which the package list is rebuilt from
21031 the latest instances of the given channels.
21034 See the hpcguix-web repository for a
21035 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
21038 @item @code{package} (default: @code{hpcguix-web})
21039 The hpcguix-web package to use.
21043 A typical hpcguix-web service declaration looks like this:
21046 (service hpcguix-web-service-type
21047 (hpcguix-web-configuration
21049 #~(define site-config
21050 (hpcweb-configuration
21051 (title-prefix "Guix-HPC - ")
21052 (menu '(("/about" "ABOUT"))))))))
21056 The hpcguix-web service periodically updates the package list it publishes by
21057 pulling channels from Git. To that end, it needs to access X.509 certificates
21058 so that it can authenticate Git servers when communicating over HTTPS, and it
21059 assumes that @file{/etc/ssl/certs} contains those certificates.
21061 Thus, make sure to add @code{nss-certs} or another certificate package to the
21062 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
21063 more information on X.509 certificates.
21066 @node Certificate Services
21067 @subsection Certificate Services
21070 @cindex HTTP, HTTPS
21071 @cindex Let's Encrypt
21072 @cindex TLS certificates
21073 The @code{(gnu services certbot)} module provides a service to
21074 automatically obtain a valid TLS certificate from the Let's Encrypt
21075 certificate authority. These certificates can then be used to serve
21076 content securely over HTTPS or other TLS-based protocols, with the
21077 knowledge that the client will be able to verify the server's
21080 @url{https://letsencrypt.org/, Let's Encrypt} provides the
21081 @code{certbot} tool to automate the certification process. This tool
21082 first securely generates a key on the server. It then makes a request
21083 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
21084 checks that the request originates from the host in question by using a
21085 challenge-response protocol, requiring the server to provide its
21086 response over HTTP. If that protocol completes successfully, the CA
21087 signs the key, resulting in a certificate. That certificate is valid
21088 for a limited period of time, and therefore to continue to provide TLS
21089 services, the server needs to periodically ask the CA to renew its
21092 The certbot service automates this process: the initial key
21093 generation, the initial certification request to the Let's Encrypt
21094 service, the web server challenge/response integration, writing the
21095 certificate to disk, the automated periodic renewals, and the deployment
21096 tasks associated with the renewal (e.g.@: reloading services, copying keys
21097 with different permissions).
21099 Certbot is run twice a day, at a random minute within the hour. It
21100 won't do anything until your certificates are due for renewal or
21101 revoked, but running it regularly would give your service a chance of
21102 staying online in case a Let's Encrypt-initiated revocation happened for
21105 By using this service, you agree to the ACME Subscriber Agreement, which
21106 can be found there:
21107 @url{https://acme-v01.api.letsencrypt.org/directory}.
21109 @defvr {Scheme Variable} certbot-service-type
21110 A service type for the @code{certbot} Let's Encrypt client. Its value
21111 must be a @code{certbot-configuration} record as in this example:
21114 (define %nginx-deploy-hook
21116 "nginx-deploy-hook"
21117 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
21118 (kill pid SIGHUP))))
21120 (service certbot-service-type
21121 (certbot-configuration
21122 (email "foo@@example.net")
21125 (certificate-configuration
21126 (domains '("example.net" "www.example.net"))
21127 (deploy-hook %nginx-deploy-hook))
21128 (certificate-configuration
21129 (domains '("bar.example.net")))))))
21132 See below for details about @code{certbot-configuration}.
21135 @deftp {Data Type} certbot-configuration
21136 Data type representing the configuration of the @code{certbot} service.
21137 This type has the following parameters:
21140 @item @code{package} (default: @code{certbot})
21141 The certbot package to use.
21143 @item @code{webroot} (default: @code{/var/www})
21144 The directory from which to serve the Let's Encrypt challenge/response
21147 @item @code{certificates} (default: @code{()})
21148 A list of @code{certificates-configuration}s for which to generate
21149 certificates and request signatures. Each certificate has a @code{name}
21150 and several @code{domains}.
21153 Mandatory email used for registration, recovery contact, and important
21154 account notifications.
21156 @item @code{server} (default: @code{#f})
21157 Optional URL of ACME server. Setting this overrides certbot's default,
21158 which is the Let's Encrypt server.
21160 @item @code{rsa-key-size} (default: @code{2048})
21161 Size of the RSA key.
21163 @item @code{default-location} (default: @i{see below})
21164 The default @code{nginx-location-configuration}. Because @code{certbot}
21165 needs to be able to serve challenges and responses, it needs to be able
21166 to run a web server. It does so by extending the @code{nginx} web
21167 service with an @code{nginx-server-configuration} listening on the
21168 @var{domains} on port 80, and which has a
21169 @code{nginx-location-configuration} for the @code{/.well-known/} URI
21170 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
21171 these nginx configuration data types.
21173 Requests to other URL paths will be matched by the
21174 @code{default-location}, which if present is added to all
21175 @code{nginx-server-configuration}s.
21177 By default, the @code{default-location} will issue a redirect from
21178 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
21179 you to define what to serve on your site via @code{https}.
21181 Pass @code{#f} to not issue a default location.
21185 @deftp {Data Type} certificate-configuration
21186 Data type representing the configuration of a certificate.
21187 This type has the following parameters:
21190 @item @code{name} (default: @i{see below})
21191 This name is used by Certbot for housekeeping and in file paths; it
21192 doesn't affect the content of the certificate itself. To see
21193 certificate names, run @code{certbot certificates}.
21195 Its default is the first provided domain.
21197 @item @code{domains} (default: @code{()})
21198 The first domain provided will be the subject CN of the certificate, and
21199 all domains will be Subject Alternative Names on the certificate.
21201 @item @code{challenge} (default: @code{#f})
21202 The challenge type that has to be run by certbot. If @code{#f} is specified,
21203 default to the HTTP challenge. If a value is specified, defaults to the
21204 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
21205 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
21206 and gives Let's Encrypt permission to log the public IP address of the
21207 requesting machine.
21209 @item @code{authentication-hook} (default: @code{#f})
21210 Command to be run in a shell once for each certificate challenge to be
21211 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
21212 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
21213 contains the validation string and @code{$CERTBOT_TOKEN} contains the
21214 file name of the resource requested when performing an HTTP-01 challenge.
21216 @item @code{cleanup-hook} (default: @code{#f})
21217 Command to be run in a shell once for each certificate challenge that
21218 have been answered by the @code{auth-hook}. For this command, the shell
21219 variables available in the @code{auth-hook} script are still available, and
21220 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
21221 of the @code{auth-hook} script.
21223 @item @code{deploy-hook} (default: @code{#f})
21224 Command to be run in a shell once for each successfully issued
21225 certificate. For this command, the shell variable
21226 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
21227 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
21228 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
21229 contain a space-delimited list of renewed certificate domains (for
21230 example, @samp{"example.com www.example.com"}.
21235 For each @code{certificate-configuration}, the certificate is saved to
21236 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
21237 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
21239 @subsection DNS Services
21240 @cindex DNS (domain name system)
21241 @cindex domain name system (DNS)
21243 The @code{(gnu services dns)} module provides services related to the
21244 @dfn{domain name system} (DNS). It provides a server service for hosting
21245 an @emph{authoritative} DNS server for multiple zones, slave or master.
21246 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
21247 caching and forwarding DNS server for the LAN, which uses
21248 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
21250 @subsubheading Knot Service
21252 An example configuration of an authoritative server for two zones, one master
21256 (define-zone-entries example.org.zone
21257 ;; Name TTL Class Type Data
21258 ("@@" "" "IN" "A" "127.0.0.1")
21259 ("@@" "" "IN" "NS" "ns")
21260 ("ns" "" "IN" "A" "127.0.0.1"))
21262 (define master-zone
21263 (knot-zone-configuration
21264 (domain "example.org")
21266 (origin "example.org")
21267 (entries example.org.zone)))))
21270 (knot-zone-configuration
21271 (domain "plop.org")
21272 (dnssec-policy "default")
21273 (master (list "plop-master"))))
21275 (define plop-master
21276 (knot-remote-configuration
21278 (address (list "208.76.58.171"))))
21282 (services (cons* (service knot-service-type
21283 (knot-configuration
21284 (remotes (list plop-master))
21285 (zones (list master-zone slave-zone))))
21290 @deffn {Scheme Variable} knot-service-type
21291 This is the type for the Knot DNS server.
21293 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
21294 zones, that is to say domain names you would buy from a registrar. This server
21295 is not a resolver, meaning that it can only resolve names for which it is
21296 authoritative. This server can be configured to serve zones as a master server
21297 or a slave server as a per-zone basis. Slave zones will get their data from
21298 masters, and will serve it as an authoritative server. From the point of view
21299 of a resolver, there is no difference between master and slave.
21301 The following data types are used to configure the Knot DNS server:
21304 @deftp {Data Type} knot-key-configuration
21305 Data type representing a key.
21306 This type has the following parameters:
21309 @item @code{id} (default: @code{""})
21310 An identifier for other configuration fields to refer to this key. IDs must
21311 be unique and must not be empty.
21313 @item @code{algorithm} (default: @code{#f})
21314 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
21315 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
21316 and @code{'hmac-sha512}.
21318 @item @code{secret} (default: @code{""})
21319 The secret key itself.
21324 @deftp {Data Type} knot-acl-configuration
21325 Data type representing an Access Control List (ACL) configuration.
21326 This type has the following parameters:
21329 @item @code{id} (default: @code{""})
21330 An identifier for ether configuration fields to refer to this key. IDs must be
21331 unique and must not be empty.
21333 @item @code{address} (default: @code{'()})
21334 An ordered list of IP addresses, network subnets, or network ranges represented
21335 with strings. The query must match one of them. Empty value means that
21336 address match is not required.
21338 @item @code{key} (default: @code{'()})
21339 An ordered list of references to keys represented with strings. The string
21340 must match a key ID defined in a @code{knot-key-configuration}. No key means
21341 that a key is not require to match that ACL.
21343 @item @code{action} (default: @code{'()})
21344 An ordered list of actions that are permitted or forbidden by this ACL. Possible
21345 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
21346 and @code{'update}.
21348 @item @code{deny?} (default: @code{#f})
21349 When true, the ACL defines restrictions. Listed actions are forbidden. When
21350 false, listed actions are allowed.
21355 @deftp {Data Type} zone-entry
21356 Data type representing a record entry in a zone file.
21357 This type has the following parameters:
21360 @item @code{name} (default: @code{"@@"})
21361 The name of the record. @code{"@@"} refers to the origin of the zone. Names
21362 are relative to the origin of the zone. For example, in the @code{example.org}
21363 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
21364 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
21365 refers to @code{ns.example.org}.
21367 @item @code{ttl} (default: @code{""})
21368 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
21370 @item @code{class} (default: @code{"IN"})
21371 The class of the record. Knot currently supports only @code{"IN"} and
21372 partially @code{"CH"}.
21374 @item @code{type} (default: @code{"A"})
21375 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
21376 address), NS (Name Server) and MX (Mail eXchange). Many other types are
21379 @item @code{data} (default: @code{""})
21380 The data contained in the record. For instance an IP address associated with
21381 an A record, or a domain name associated with an NS record. Remember that
21382 domain names are relative to the origin unless they end with a dot.
21387 @deftp {Data Type} zone-file
21388 Data type representing the content of a zone file.
21389 This type has the following parameters:
21392 @item @code{entries} (default: @code{'()})
21393 The list of entries. The SOA record is taken care of, so you don't need to
21394 put it in the list of entries. This list should probably contain an entry
21395 for your primary authoritative DNS server. Other than using a list of entries
21396 directly, you can use @code{define-zone-entries} to define a object containing
21397 the list of entries more easily, that you can later pass to the @code{entries}
21398 field of the @code{zone-file}.
21400 @item @code{origin} (default: @code{""})
21401 The name of your zone. This parameter cannot be empty.
21403 @item @code{ns} (default: @code{"ns"})
21404 The domain of your primary authoritative DNS server. The name is relative to
21405 the origin, unless it ends with a dot. It is mandatory that this primary
21406 DNS server corresponds to an NS record in the zone and that it is associated
21407 to an IP address in the list of entries.
21409 @item @code{mail} (default: @code{"hostmaster"})
21410 An email address people can contact you at, as the owner of the zone. This
21411 is translated as @code{<mail>@@<origin>}.
21413 @item @code{serial} (default: @code{1})
21414 The serial number of the zone. As this is used to keep track of changes by
21415 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
21416 Always increment it when you make a change in your zone.
21418 @item @code{refresh} (default: @code{(* 2 24 3600)})
21419 The frequency at which slaves will do a zone transfer. This value is a number
21420 of seconds. It can be computed by multiplications or with
21421 @code{(string->duration)}.
21423 @item @code{retry} (default: @code{(* 15 60)})
21424 The period after which a slave will retry to contact its master when it fails
21425 to do so a first time.
21427 @item @code{expiry} (default: @code{(* 14 24 3600)})
21428 Default TTL of records. Existing records are considered correct for at most
21429 this amount of time. After this period, resolvers will invalidate their cache
21430 and check again that it still exists.
21432 @item @code{nx} (default: @code{3600})
21433 Default TTL of inexistant records. This delay is usually short because you want
21434 your new domains to reach everyone quickly.
21439 @deftp {Data Type} knot-remote-configuration
21440 Data type representing a remote configuration.
21441 This type has the following parameters:
21444 @item @code{id} (default: @code{""})
21445 An identifier for other configuration fields to refer to this remote. IDs must
21446 be unique and must not be empty.
21448 @item @code{address} (default: @code{'()})
21449 An ordered list of destination IP addresses. Addresses are tried in sequence.
21450 An optional port can be given with the @@ separator. For instance:
21451 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
21453 @item @code{via} (default: @code{'()})
21454 An ordered list of source IP addresses. An empty list will have Knot choose
21455 an appropriate source IP. An optional port can be given with the @@ separator.
21456 The default is to choose at random.
21458 @item @code{key} (default: @code{#f})
21459 A reference to a key, that is a string containing the identifier of a key
21460 defined in a @code{knot-key-configuration} field.
21465 @deftp {Data Type} knot-keystore-configuration
21466 Data type representing a keystore to hold dnssec keys.
21467 This type has the following parameters:
21470 @item @code{id} (default: @code{""})
21471 The id of the keystore. It must not be empty.
21473 @item @code{backend} (default: @code{'pem})
21474 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
21476 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
21477 The configuration string of the backend. An example for the PKCS#11 is:
21478 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
21479 For the pem backend, the string represents a path in the file system.
21484 @deftp {Data Type} knot-policy-configuration
21485 Data type representing a dnssec policy. Knot DNS is able to automatically
21486 sign your zones. It can either generate and manage your keys automatically or
21487 use keys that you generate.
21489 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
21490 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
21491 zone. In order to be trusted, the KSK needs to be present in the parent zone
21492 (usually a top-level domain). If your registrar supports dnssec, you will
21493 have to send them your KSK's hash so they can add a DS record in their zone.
21494 This is not automated and need to be done each time you change your KSK.
21496 The policy also defines the lifetime of keys. Usually, ZSK can be changed
21497 easily and use weaker cryptographic functions (they use lower parameters) in
21498 order to sign records quickly, so they are changed often. The KSK however
21499 requires manual interaction with the registrar, so they are changed less often
21500 and use stronger parameters because they sign only one record.
21502 This type has the following parameters:
21505 @item @code{id} (default: @code{""})
21506 The id of the policy. It must not be empty.
21508 @item @code{keystore} (default: @code{"default"})
21509 A reference to a keystore, that is a string containing the identifier of a
21510 keystore defined in a @code{knot-keystore-configuration} field. The
21511 @code{"default"} identifier means the default keystore (a kasp database that
21512 was setup by this service).
21514 @item @code{manual?} (default: @code{#f})
21515 Whether the key management is manual or automatic.
21517 @item @code{single-type-signing?} (default: @code{#f})
21518 When @code{#t}, use the Single-Type Signing Scheme.
21520 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
21521 An algorithm of signing keys and issued signatures.
21523 @item @code{ksk-size} (default: @code{256})
21524 The length of the KSK. Note that this value is correct for the default
21525 algorithm, but would be unsecure for other algorithms.
21527 @item @code{zsk-size} (default: @code{256})
21528 The length of the ZSK. Note that this value is correct for the default
21529 algorithm, but would be unsecure for other algorithms.
21531 @item @code{dnskey-ttl} (default: @code{'default})
21532 The TTL value for DNSKEY records added into zone apex. The special
21533 @code{'default} value means same as the zone SOA TTL.
21535 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
21536 The period between ZSK publication and the next rollover initiation.
21538 @item @code{propagation-delay} (default: @code{(* 24 3600)})
21539 An extra delay added for each key rollover step. This value should be high
21540 enough to cover propagation of data from the master server to all slaves.
21542 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
21543 A validity period of newly issued signatures.
21545 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
21546 A period how long before a signature expiration the signature will be refreshed.
21548 @item @code{nsec3?} (default: @code{#f})
21549 When @code{#t}, NSEC3 will be used instead of NSEC.
21551 @item @code{nsec3-iterations} (default: @code{5})
21552 The number of additional times the hashing is performed.
21554 @item @code{nsec3-salt-length} (default: @code{8})
21555 The length of a salt field in octets, which is appended to the original owner
21556 name before hashing.
21558 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
21559 The validity period of newly issued salt field.
21564 @deftp {Data Type} knot-zone-configuration
21565 Data type representing a zone served by Knot.
21566 This type has the following parameters:
21569 @item @code{domain} (default: @code{""})
21570 The domain served by this configuration. It must not be empty.
21572 @item @code{file} (default: @code{""})
21573 The file where this zone is saved. This parameter is ignored by master zones.
21574 Empty means default location that depends on the domain name.
21576 @item @code{zone} (default: @code{(zone-file)})
21577 The content of the zone file. This parameter is ignored by slave zones. It
21578 must contain a zone-file record.
21580 @item @code{master} (default: @code{'()})
21581 A list of master remotes. When empty, this zone is a master. When set, this
21582 zone is a slave. This is a list of remotes identifiers.
21584 @item @code{ddns-master} (default: @code{#f})
21585 The main master. When empty, it defaults to the first master in the list of
21588 @item @code{notify} (default: @code{'()})
21589 A list of slave remote identifiers.
21591 @item @code{acl} (default: @code{'()})
21592 A list of acl identifiers.
21594 @item @code{semantic-checks?} (default: @code{#f})
21595 When set, this adds more semantic checks to the zone.
21597 @item @code{disable-any?} (default: @code{#f})
21598 When set, this forbids queries of the ANY type.
21600 @item @code{zonefile-sync} (default: @code{0})
21601 The delay between a modification in memory and on disk. 0 means immediate
21604 @item @code{zonefile-load} (default: @code{#f})
21605 The way the zone file contents are applied during zone load. Possible values
21609 @item @code{#f} for using the default value from Knot,
21610 @item @code{'none} for not using the zone file at all,
21611 @item @code{'difference} for computing the difference between already available
21612 contents and zone contents and applying it to the current zone contents,
21613 @item @code{'difference-no-serial} for the same as @code{'difference}, but
21614 ignoring the SOA serial in the zone file, while the server takes care of it
21616 @item @code{'whole} for loading zone contents from the zone file.
21619 @item @code{journal-content} (default: @code{#f})
21620 The way the journal is used to store zone and its changes. Possible values
21621 are @code{'none} to not use it at all, @code{'changes} to store changes and
21622 @code{'all} to store contents. @code{#f} does not set this option, so the
21623 default value from Knot is used.
21625 @item @code{max-journal-usage} (default: @code{#f})
21626 The maximum size for the journal on disk. @code{#f} does not set this option,
21627 so the default value from Knot is used.
21629 @item @code{max-journal-depth} (default: @code{#f})
21630 The maximum size of the history. @code{#f} does not set this option, so the
21631 default value from Knot is used.
21633 @item @code{max-zone-size} (default: @code{#f})
21634 The maximum size of the zone file. This limit is enforced for incoming
21635 transfer and updates. @code{#f} does not set this option, so the default
21636 value from Knot is used.
21638 @item @code{dnssec-policy} (default: @code{#f})
21639 A reference to a @code{knot-policy-configuration} record, or the special
21640 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
21643 @item @code{serial-policy} (default: @code{'increment})
21644 A policy between @code{'increment} and @code{'unixtime}.
21649 @deftp {Data Type} knot-configuration
21650 Data type representing the Knot configuration.
21651 This type has the following parameters:
21654 @item @code{knot} (default: @code{knot})
21657 @item @code{run-directory} (default: @code{"/var/run/knot"})
21658 The run directory. This directory will be used for pid file and sockets.
21660 @item @code{includes} (default: @code{'()})
21661 A list of strings or file-like objects denoting other files that must be
21662 included at the top of the configuration file.
21664 @cindex secrets, Knot service
21665 This can be used to manage secrets out-of-band. For example, secret
21666 keys may be stored in an out-of-band file not managed by Guix, and
21667 thus not visible in @file{/gnu/store}---e.g., you could store secret
21668 key configuration in @file{/etc/knot/secrets.conf} and add this file
21669 to the @code{includes} list.
21671 One can generate a secret tsig key (for nsupdate and zone transfers with the
21672 keymgr command from the knot package. Note that the package is not automatically
21673 installed by the service. The following example shows how to generate a new
21677 keymgr -t mysecret > /etc/knot/secrets.conf
21678 chmod 600 /etc/knot/secrets.conf
21681 Also note that the generated key will be named @var{mysecret}, so it is the
21682 name that needs to be used in the @var{key} field of the
21683 @code{knot-acl-configuration} record and in other places that need to refer
21686 It can also be used to add configuration not supported by this interface.
21688 @item @code{listen-v4} (default: @code{"0.0.0.0"})
21689 An ip address on which to listen.
21691 @item @code{listen-v6} (default: @code{"::"})
21692 An ip address on which to listen.
21694 @item @code{listen-port} (default: @code{53})
21695 A port on which to listen.
21697 @item @code{keys} (default: @code{'()})
21698 The list of knot-key-configuration used by this configuration.
21700 @item @code{acls} (default: @code{'()})
21701 The list of knot-acl-configuration used by this configuration.
21703 @item @code{remotes} (default: @code{'()})
21704 The list of knot-remote-configuration used by this configuration.
21706 @item @code{zones} (default: @code{'()})
21707 The list of knot-zone-configuration used by this configuration.
21712 @subsubheading Knot Resolver Service
21714 @deffn {Scheme Variable} knot-resolver-service-type
21715 This this the type of the knot resolver service, whose value should be
21716 an @code{knot-resolver-configuration} object as in this example:
21719 (service knot-resolver-service-type
21720 (knot-resolver-configuration
21721 (kresd-config-file (plain-file "kresd.conf" "
21722 net.listen('192.168.0.1', 5353)
21723 user('knot-resolver', 'knot-resolver')
21724 modules = @{ 'hints > iterate', 'stats', 'predict' @}
21725 cache.size = 100 * MB
21729 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
21732 @deftp {Data Type} knot-resolver-configuration
21733 Data type representing the configuration of knot-resolver.
21736 @item @code{package} (default: @var{knot-resolver})
21737 Package object of the knot DNS resolver.
21739 @item @code{kresd-config-file} (default: %kresd.conf)
21740 File-like object of the kresd configuration file to use, by default it
21741 will listen on @code{127.0.0.1} and @code{::1}.
21743 @item @code{garbage-collection-interval} (default: 1000)
21744 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
21750 @subsubheading Dnsmasq Service
21752 @deffn {Scheme Variable} dnsmasq-service-type
21753 This is the type of the dnsmasq service, whose value should be an
21754 @code{dnsmasq-configuration} object as in this example:
21757 (service dnsmasq-service-type
21758 (dnsmasq-configuration
21760 (servers '("192.168.1.1"))))
21764 @deftp {Data Type} dnsmasq-configuration
21765 Data type representing the configuration of dnsmasq.
21768 @item @code{package} (default: @var{dnsmasq})
21769 Package object of the dnsmasq server.
21771 @item @code{no-hosts?} (default: @code{#f})
21772 When true, don't read the hostnames in /etc/hosts.
21774 @item @code{port} (default: @code{53})
21775 The port to listen on. Setting this to zero completely disables DNS
21776 responses, leaving only DHCP and/or TFTP functions.
21778 @item @code{local-service?} (default: @code{#t})
21779 Accept DNS queries only from hosts whose address is on a local subnet,
21780 ie a subnet for which an interface exists on the server.
21782 @item @code{listen-addresses} (default: @code{'()})
21783 Listen on the given IP addresses.
21785 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
21786 The file to read the IP address of the upstream nameservers from.
21788 @item @code{no-resolv?} (default: @code{#f})
21789 When true, don't read @var{resolv-file}.
21791 @item @code{servers} (default: @code{'()})
21792 Specify IP address of upstream servers directly.
21794 @item @code{cache-size} (default: @code{150})
21795 Set the size of dnsmasq's cache. Setting the cache size to zero
21798 @item @code{negative-cache?} (default: @code{#t})
21799 When false, disable negative caching.
21804 @subsubheading ddclient Service
21807 The ddclient service described below runs the ddclient daemon, which takes
21808 care of automatically updating DNS entries for service providers such as
21809 @uref{https://dyn.com/dns/, Dyn}.
21811 The following example show instantiates the service with its default
21815 (service ddclient-service-type)
21818 Note that ddclient needs to access credentials that are stored in a
21819 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
21820 @code{secret-file} below.) You are expected to create this file manually, in
21821 an ``out-of-band'' fashion (you @emph{could} make this file part of the
21822 service configuration, for instance by using @code{plain-file}, but it will be
21823 world-readable @i{via} @file{/gnu/store}.) See the examples in the
21824 @file{share/ddclient} directory of the @code{ddclient} package.
21826 @c %start of fragment
21828 Available @code{ddclient-configuration} fields are:
21830 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
21831 The ddclient package.
21835 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
21836 The period after which ddclient will retry to check IP and domain name.
21838 Defaults to @samp{300}.
21842 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
21843 Use syslog for the output.
21845 Defaults to @samp{#t}.
21849 @deftypevr {@code{ddclient-configuration} parameter} string mail
21852 Defaults to @samp{"root"}.
21856 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
21857 Mail failed update to user.
21859 Defaults to @samp{"root"}.
21863 @deftypevr {@code{ddclient-configuration} parameter} string pid
21864 The ddclient PID file.
21866 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
21870 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
21871 Enable SSL support.
21873 Defaults to @samp{#t}.
21877 @deftypevr {@code{ddclient-configuration} parameter} string user
21878 Specifies the user name or ID that is used when running ddclient
21881 Defaults to @samp{"ddclient"}.
21885 @deftypevr {@code{ddclient-configuration} parameter} string group
21886 Group of the user who will run the ddclient program.
21888 Defaults to @samp{"ddclient"}.
21892 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
21893 Secret file which will be appended to @file{ddclient.conf} file. This
21894 file contains credentials for use by ddclient. You are expected to
21895 create it manually.
21897 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
21901 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
21902 Extra options will be appended to @file{ddclient.conf} file.
21904 Defaults to @samp{()}.
21909 @c %end of fragment
21913 @subsection VPN Services
21914 @cindex VPN (virtual private network)
21915 @cindex virtual private network (VPN)
21917 The @code{(gnu services vpn)} module provides services related to
21918 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
21919 your machine to connect to a VPN, and a @emph{server} service for your machine
21920 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
21922 @deffn {Scheme Procedure} openvpn-client-service @
21923 [#:config (openvpn-client-configuration)]
21925 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
21928 @deffn {Scheme Procedure} openvpn-server-service @
21929 [#:config (openvpn-server-configuration)]
21931 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
21933 Both can be run simultaneously.
21936 @c %automatically generated documentation
21938 Available @code{openvpn-client-configuration} fields are:
21940 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
21941 The OpenVPN package.
21945 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
21946 The OpenVPN pid file.
21948 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21952 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
21953 The protocol (UDP or TCP) used to open a channel between clients and
21956 Defaults to @samp{udp}.
21960 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
21961 The device type used to represent the VPN connection.
21963 Defaults to @samp{tun}.
21967 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
21968 The certificate authority to check connections against.
21970 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21974 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
21975 The certificate of the machine the daemon is running on. It should be
21976 signed by the authority given in @code{ca}.
21978 Defaults to @samp{"/etc/openvpn/client.crt"}.
21982 @deftypevr {@code{openvpn-client-configuration} parameter} string key
21983 The key of the machine the daemon is running on. It must be the key whose
21984 certificate is @code{cert}.
21986 Defaults to @samp{"/etc/openvpn/client.key"}.
21990 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
21991 Whether to use the lzo compression algorithm.
21993 Defaults to @samp{#t}.
21997 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
21998 Don't re-read key files across SIGUSR1 or --ping-restart.
22000 Defaults to @samp{#t}.
22004 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
22005 Don't close and reopen TUN/TAP device or run up/down scripts across
22006 SIGUSR1 or --ping-restart restarts.
22008 Defaults to @samp{#t}.
22012 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
22013 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22014 poll/epoll/select prior to the write operation.
22016 Defaults to @samp{#f}.
22019 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
22022 Defaults to @samp{3}.
22026 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
22027 Add an additional layer of HMAC authentication on top of the TLS control
22028 channel to protect against DoS attacks.
22030 Defaults to @samp{#f}.
22034 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
22035 Authenticate with server using username/password. The option is a file
22036 containing username/password on 2 lines. Do not use a file-like object as it
22037 would be added to the store and readable by any user.
22039 Defaults to @samp{'disabled}.
22042 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
22043 Whether to check the server certificate has server usage extension.
22045 Defaults to @samp{#t}.
22049 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
22050 Bind to a specific local port number.
22052 Defaults to @samp{#f}.
22056 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
22057 Retry resolving server address.
22059 Defaults to @samp{#t}.
22063 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
22064 A list of remote servers to connect to.
22066 Defaults to @samp{()}.
22068 Available @code{openvpn-remote-configuration} fields are:
22070 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
22073 Defaults to @samp{"my-server"}.
22077 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
22078 Port number the server listens to.
22080 Defaults to @samp{1194}.
22085 @c %end of automatic openvpn-client documentation
22087 @c %automatically generated documentation
22089 Available @code{openvpn-server-configuration} fields are:
22091 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
22092 The OpenVPN package.
22096 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
22097 The OpenVPN pid file.
22099 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
22103 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
22104 The protocol (UDP or TCP) used to open a channel between clients and
22107 Defaults to @samp{udp}.
22111 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
22112 The device type used to represent the VPN connection.
22114 Defaults to @samp{tun}.
22118 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
22119 The certificate authority to check connections against.
22121 Defaults to @samp{"/etc/openvpn/ca.crt"}.
22125 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
22126 The certificate of the machine the daemon is running on. It should be
22127 signed by the authority given in @code{ca}.
22129 Defaults to @samp{"/etc/openvpn/client.crt"}.
22133 @deftypevr {@code{openvpn-server-configuration} parameter} string key
22134 The key of the machine the daemon is running on. It must be the key whose
22135 certificate is @code{cert}.
22137 Defaults to @samp{"/etc/openvpn/client.key"}.
22141 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
22142 Whether to use the lzo compression algorithm.
22144 Defaults to @samp{#t}.
22148 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
22149 Don't re-read key files across SIGUSR1 or --ping-restart.
22151 Defaults to @samp{#t}.
22155 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
22156 Don't close and reopen TUN/TAP device or run up/down scripts across
22157 SIGUSR1 or --ping-restart restarts.
22159 Defaults to @samp{#t}.
22163 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
22164 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22165 poll/epoll/select prior to the write operation.
22167 Defaults to @samp{#f}.
22170 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
22173 Defaults to @samp{3}.
22177 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
22178 Add an additional layer of HMAC authentication on top of the TLS control
22179 channel to protect against DoS attacks.
22181 Defaults to @samp{#f}.
22185 @deftypevr {@code{openvpn-server-configuration} parameter} number port
22186 Specifies the port number on which the server listens.
22188 Defaults to @samp{1194}.
22192 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
22193 An ip and mask specifying the subnet inside the virtual network.
22195 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
22199 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
22200 A CIDR notation specifying the IPv6 subnet inside the virtual network.
22202 Defaults to @samp{#f}.
22206 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
22207 The Diffie-Hellman parameters file.
22209 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
22213 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
22214 The file that records client IPs.
22216 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
22220 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
22221 When true, the server will act as a gateway for its clients.
22223 Defaults to @samp{#f}.
22227 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
22228 When true, clients are allowed to talk to each other inside the VPN.
22230 Defaults to @samp{#f}.
22234 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
22235 Causes ping-like messages to be sent back and forth over the link so
22236 that each side knows when the other side has gone down. @code{keepalive}
22237 requires a pair. The first element is the period of the ping sending,
22238 and the second element is the timeout before considering the other side
22243 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
22244 The maximum number of clients.
22246 Defaults to @samp{100}.
22250 @deftypevr {@code{openvpn-server-configuration} parameter} string status
22251 The status file. This file shows a small report on current connection.
22252 It is truncated and rewritten every minute.
22254 Defaults to @samp{"/var/run/openvpn/status"}.
22258 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
22259 The list of configuration for some clients.
22261 Defaults to @samp{()}.
22263 Available @code{openvpn-ccd-configuration} fields are:
22265 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
22268 Defaults to @samp{"client"}.
22272 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
22275 Defaults to @samp{#f}.
22279 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
22282 Defaults to @samp{#f}.
22289 @c %end of automatic openvpn-server documentation
22292 @node Network File System
22293 @subsection Network File System
22296 The @code{(gnu services nfs)} module provides the following services,
22297 which are most commonly used in relation to mounting or exporting
22298 directory trees as @dfn{network file systems} (NFS).
22300 While it is possible to use the individual components that together make
22301 up a Network File System service, we recommended to configure an NFS
22302 server with the @code{nfs-service-type}.
22304 @subsubheading NFS Service
22305 @cindex NFS, server
22307 The NFS service takes care of setting up all NFS component services,
22308 kernel configuration file systems, and installs configuration files in
22309 the locations that NFS expects.
22311 @defvr {Scheme Variable} nfs-service-type
22312 A service type for a complete NFS server.
22315 @deftp {Data Type} nfs-configuration
22316 This data type represents the configuration of the NFS service and all
22319 It has the following parameters:
22321 @item @code{nfs-utils} (default: @code{nfs-utils})
22322 The nfs-utils package to use.
22324 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
22325 If a list of string values is provided, the @command{rpc.nfsd} daemon
22326 will be limited to supporting the given versions of the NFS protocol.
22328 @item @code{exports} (default: @code{'()})
22329 This is a list of directories the NFS server should export. Each entry
22330 is a list consisting of two elements: a directory name and a string
22331 containing all options. This is an example in which the directory
22332 @file{/export} is served to all NFS clients as a read-only share:
22338 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
22341 @item @code{rpcmountd-port} (default: @code{#f})
22342 The network port that the @command{rpc.mountd} daemon should use.
22344 @item @code{rpcstatd-port} (default: @code{#f})
22345 The network port that the @command{rpc.statd} daemon should use.
22347 @item @code{rpcbind} (default: @code{rpcbind})
22348 The rpcbind package to use.
22350 @item @code{idmap-domain} (default: @code{"localdomain"})
22351 The local NFSv4 domain name.
22353 @item @code{nfsd-port} (default: @code{2049})
22354 The network port that the @command{nfsd} daemon should use.
22356 @item @code{nfsd-threads} (default: @code{8})
22357 The number of threads used by the @command{nfsd} daemon.
22359 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22360 The directory where the pipefs file system is mounted.
22362 @item @code{debug} (default: @code{'()"})
22363 A list of subsystems for which debugging output should be enabled. This
22364 is a list of symbols. Any of these symbols are valid: @code{nfsd},
22365 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
22369 If you don't need a complete NFS service or prefer to build it yourself
22370 you can use the individual component services that are documented below.
22372 @subsubheading RPC Bind Service
22375 The RPC Bind service provides a facility to map program numbers into
22376 universal addresses.
22377 Many NFS related services use this facility. Hence it is automatically
22378 started when a dependent service starts.
22380 @defvr {Scheme Variable} rpcbind-service-type
22381 A service type for the RPC portmapper daemon.
22385 @deftp {Data Type} rpcbind-configuration
22386 Data type representing the configuration of the RPC Bind Service.
22387 This type has the following parameters:
22389 @item @code{rpcbind} (default: @code{rpcbind})
22390 The rpcbind package to use.
22392 @item @code{warm-start?} (default: @code{#t})
22393 If this parameter is @code{#t}, then the daemon will read a
22394 state file on startup thus reloading state information saved by a previous
22400 @subsubheading Pipefs Pseudo File System
22404 The pipefs file system is used to transfer NFS related data
22405 between the kernel and user space programs.
22407 @defvr {Scheme Variable} pipefs-service-type
22408 A service type for the pipefs pseudo file system.
22411 @deftp {Data Type} pipefs-configuration
22412 Data type representing the configuration of the pipefs pseudo file system service.
22413 This type has the following parameters:
22415 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22416 The directory to which the file system is to be attached.
22421 @subsubheading GSS Daemon Service
22424 @cindex global security system
22426 The @dfn{global security system} (GSS) daemon provides strong security for RPC
22428 Before exchanging RPC requests an RPC client must establish a security
22429 context. Typically this is done using the Kerberos command @command{kinit}
22430 or automatically at login time using PAM services (@pxref{Kerberos Services}).
22432 @defvr {Scheme Variable} gss-service-type
22433 A service type for the Global Security System (GSS) daemon.
22436 @deftp {Data Type} gss-configuration
22437 Data type representing the configuration of the GSS daemon service.
22438 This type has the following parameters:
22440 @item @code{nfs-utils} (default: @code{nfs-utils})
22441 The package in which the @command{rpc.gssd} command is to be found.
22443 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22444 The directory where the pipefs file system is mounted.
22450 @subsubheading IDMAP Daemon Service
22452 @cindex name mapper
22454 The idmap daemon service provides mapping between user IDs and user names.
22455 Typically it is required in order to access file systems mounted via NFSv4.
22457 @defvr {Scheme Variable} idmap-service-type
22458 A service type for the Identity Mapper (IDMAP) daemon.
22461 @deftp {Data Type} idmap-configuration
22462 Data type representing the configuration of the IDMAP daemon service.
22463 This type has the following parameters:
22465 @item @code{nfs-utils} (default: @code{nfs-utils})
22466 The package in which the @command{rpc.idmapd} command is to be found.
22468 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22469 The directory where the pipefs file system is mounted.
22471 @item @code{domain} (default: @code{#f})
22472 The local NFSv4 domain name.
22473 This must be a string or @code{#f}.
22474 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
22476 @item @code{verbosity} (default: @code{0})
22477 The verbosity level of the daemon.
22482 @node Continuous Integration
22483 @subsection Continuous Integration
22485 @cindex continuous integration
22486 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
22487 continuous integration tool for Guix. It can be used both for development and
22488 for providing substitutes to others (@pxref{Substitutes}).
22490 The @code{(gnu services cuirass)} module provides the following service.
22492 @defvr {Scheme Procedure} cuirass-service-type
22493 The type of the Cuirass service. Its value must be a
22494 @code{cuirass-configuration} object, as described below.
22497 To add build jobs, you have to set the @code{specifications} field of the
22498 configuration. Here is an example of a service that polls the Guix repository
22499 and builds the packages from a manifest. Some of the packages are defined in
22500 the @code{"custom-packages"} input, which is the equivalent of
22501 @code{GUIX_PACKAGE_PATH}.
22504 (define %cuirass-specs
22506 '((#:name . "my-manifest")
22507 (#:load-path-inputs . ("guix"))
22508 (#:package-path-inputs . ("custom-packages"))
22509 (#:proc-input . "guix")
22510 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
22511 (#:proc . cuirass-jobs)
22512 (#:proc-args . ((subset . "manifests")
22513 (systems . ("x86_64-linux"))
22514 (manifests . (("config" . "guix/manifest.scm")))))
22515 (#:inputs . (((#:name . "guix")
22516 (#:url . "git://git.savannah.gnu.org/guix.git")
22517 (#:load-path . ".")
22518 (#:branch . "master")
22519 (#:no-compile? . #t))
22520 ((#:name . "config")
22521 (#:url . "https://git.example.org/config.git")
22522 (#:load-path . ".")
22523 (#:branch . "master")
22524 (#:no-compile? . #t))
22525 ((#:name . "custom-packages")
22526 (#:url . "https://git.example.org/custom-packages.git")
22527 (#:load-path . ".")
22528 (#:branch . "master")
22529 (#:no-compile? . #t)))))))
22531 (service cuirass-service-type
22532 (cuirass-configuration
22533 (specifications %cuirass-specs)))
22536 While information related to build jobs is located directly in the
22537 specifications, global settings for the @command{cuirass} process are
22538 accessible in other @code{cuirass-configuration} fields.
22540 @deftp {Data Type} cuirass-configuration
22541 Data type representing the configuration of Cuirass.
22544 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
22545 Location of the log file.
22547 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
22548 Location of the log file used by the web interface.
22550 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
22551 Location of the repository cache.
22553 @item @code{user} (default: @code{"cuirass"})
22554 Owner of the @code{cuirass} process.
22556 @item @code{group} (default: @code{"cuirass"})
22557 Owner's group of the @code{cuirass} process.
22559 @item @code{interval} (default: @code{60})
22560 Number of seconds between the poll of the repositories followed by the
22563 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
22564 Location of sqlite database which contains the build results and previously
22565 added specifications.
22567 @item @code{ttl} (default: @code{(* 30 24 3600)})
22568 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
22569 are registered for build results. This means that build results are protected
22570 from garbage collection for at least @var{ttl} seconds.
22572 @item @code{port} (default: @code{8081})
22573 Port number used by the HTTP server.
22575 @item @code{host} (default: @code{"localhost"})
22576 Listen on the network interface for @var{host}. The default is to
22577 accept connections from localhost.
22579 @item @code{specifications} (default: @code{#~'()})
22580 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
22581 where a specification is an association list
22582 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
22583 keys are keywords (@code{#:keyword-example}) as shown in the example
22586 @item @code{use-substitutes?} (default: @code{#f})
22587 This allows using substitutes to avoid building every dependencies of a job
22590 @item @code{one-shot?} (default: @code{#f})
22591 Only evaluate specifications and build derivations once.
22593 @item @code{fallback?} (default: @code{#f})
22594 When substituting a pre-built binary fails, fall back to building
22597 @item @code{extra-options} (default: @code{'()})
22598 Extra options to pass when running the Cuirass processes.
22600 @item @code{cuirass} (default: @code{cuirass})
22601 The Cuirass package to use.
22605 @node Power Management Services
22606 @subsection Power Management Services
22609 @cindex power management with TLP
22610 @subsubheading TLP daemon
22612 The @code{(gnu services pm)} module provides a Guix service definition
22613 for the Linux power management tool TLP.
22615 TLP enables various powersaving modes in userspace and kernel.
22616 Contrary to @code{upower-service}, it is not a passive,
22617 monitoring tool, as it will apply custom settings each time a new power
22618 source is detected. More information can be found at
22619 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
22621 @deffn {Scheme Variable} tlp-service-type
22622 The service type for the TLP tool. Its value should be a valid
22623 TLP configuration (see below). To use the default settings, simply
22626 (service tlp-service-type)
22630 By default TLP does not need much configuration but most TLP parameters
22631 can be tweaked using @code{tlp-configuration}.
22633 Each parameter definition is preceded by its type; for example,
22634 @samp{boolean foo} indicates that the @code{foo} parameter
22635 should be specified as a boolean. Types starting with
22636 @code{maybe-} denote parameters that won't show up in TLP config file
22637 when their value is @code{'disabled}.
22639 @c The following documentation was initially generated by
22640 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
22641 @c documentation is better, so we shouldn't hesitate to edit below as
22642 @c needed. However if the change you want to make to this documentation
22643 @c can be done in an automated way, it's probably easier to change
22644 @c (generate-documentation) than to make it below and have to deal with
22645 @c the churn as TLP updates.
22647 Available @code{tlp-configuration} fields are:
22649 @deftypevr {@code{tlp-configuration} parameter} package tlp
22654 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
22655 Set to true if you wish to enable TLP.
22657 Defaults to @samp{#t}.
22661 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
22662 Default mode when no power supply can be detected. Alternatives are AC
22665 Defaults to @samp{"AC"}.
22669 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
22670 Number of seconds Linux kernel has to wait after the disk goes idle,
22671 before syncing on AC.
22673 Defaults to @samp{0}.
22677 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
22678 Same as @code{disk-idle-ac} but on BAT mode.
22680 Defaults to @samp{2}.
22684 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
22685 Dirty pages flushing periodicity, expressed in seconds.
22687 Defaults to @samp{15}.
22691 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
22692 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
22694 Defaults to @samp{60}.
22698 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
22699 CPU frequency scaling governor on AC mode. With intel_pstate driver,
22700 alternatives are powersave and performance. With acpi-cpufreq driver,
22701 alternatives are ondemand, powersave, performance and conservative.
22703 Defaults to @samp{disabled}.
22707 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
22708 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
22710 Defaults to @samp{disabled}.
22714 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
22715 Set the min available frequency for the scaling governor on AC.
22717 Defaults to @samp{disabled}.
22721 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
22722 Set the max available frequency for the scaling governor on AC.
22724 Defaults to @samp{disabled}.
22728 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
22729 Set the min available frequency for the scaling governor on BAT.
22731 Defaults to @samp{disabled}.
22735 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
22736 Set the max available frequency for the scaling governor on BAT.
22738 Defaults to @samp{disabled}.
22742 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
22743 Limit the min P-state to control the power dissipation of the CPU, in AC
22744 mode. Values are stated as a percentage of the available performance.
22746 Defaults to @samp{disabled}.
22750 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
22751 Limit the max P-state to control the power dissipation of the CPU, in AC
22752 mode. Values are stated as a percentage of the available performance.
22754 Defaults to @samp{disabled}.
22758 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
22759 Same as @code{cpu-min-perf-on-ac} on BAT mode.
22761 Defaults to @samp{disabled}.
22765 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
22766 Same as @code{cpu-max-perf-on-ac} on BAT mode.
22768 Defaults to @samp{disabled}.
22772 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
22773 Enable CPU turbo boost feature on AC mode.
22775 Defaults to @samp{disabled}.
22779 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
22780 Same as @code{cpu-boost-on-ac?} on BAT mode.
22782 Defaults to @samp{disabled}.
22786 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
22787 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
22788 used under light load conditions.
22790 Defaults to @samp{#f}.
22794 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
22795 Same as @code{sched-powersave-on-ac?} but on BAT mode.
22797 Defaults to @samp{#t}.
22801 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
22802 Enable Linux kernel NMI watchdog.
22804 Defaults to @samp{#f}.
22808 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
22809 For Linux kernels with PHC patch applied, change CPU voltages. An
22810 example value would be @samp{"F:V F:V F:V F:V"}.
22812 Defaults to @samp{disabled}.
22816 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
22817 Set CPU performance versus energy saving policy on AC. Alternatives are
22818 performance, normal, powersave.
22820 Defaults to @samp{"performance"}.
22824 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
22825 Same as @code{energy-perf-policy-ac} but on BAT mode.
22827 Defaults to @samp{"powersave"}.
22831 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
22836 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
22837 Hard disk advanced power management level.
22841 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
22842 Same as @code{disk-apm-bat} but on BAT mode.
22846 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
22847 Hard disk spin down timeout. One value has to be specified for each
22848 declared hard disk.
22850 Defaults to @samp{disabled}.
22854 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
22855 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
22857 Defaults to @samp{disabled}.
22861 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
22862 Select IO scheduler for disk devices. One value has to be specified for
22863 each declared hard disk. Example alternatives are cfq, deadline and
22866 Defaults to @samp{disabled}.
22870 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
22871 SATA aggressive link power management (ALPM) level. Alternatives are
22872 min_power, medium_power, max_performance.
22874 Defaults to @samp{"max_performance"}.
22878 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
22879 Same as @code{sata-linkpwr-ac} but on BAT mode.
22881 Defaults to @samp{"min_power"}.
22885 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
22886 Exclude specified SATA host devices for link power management.
22888 Defaults to @samp{disabled}.
22892 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
22893 Enable Runtime Power Management for AHCI controller and disks on AC
22896 Defaults to @samp{disabled}.
22900 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
22901 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
22903 Defaults to @samp{disabled}.
22907 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
22908 Seconds of inactivity before disk is suspended.
22910 Defaults to @samp{15}.
22914 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
22915 PCI Express Active State Power Management level. Alternatives are
22916 default, performance, powersave.
22918 Defaults to @samp{"performance"}.
22922 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
22923 Same as @code{pcie-aspm-ac} but on BAT mode.
22925 Defaults to @samp{"powersave"}.
22929 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
22930 Radeon graphics clock speed level. Alternatives are low, mid, high,
22933 Defaults to @samp{"high"}.
22937 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
22938 Same as @code{radeon-power-ac} but on BAT mode.
22940 Defaults to @samp{"low"}.
22944 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
22945 Radeon dynamic power management method (DPM). Alternatives are battery,
22948 Defaults to @samp{"performance"}.
22952 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
22953 Same as @code{radeon-dpm-state-ac} but on BAT mode.
22955 Defaults to @samp{"battery"}.
22959 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
22960 Radeon DPM performance level. Alternatives are auto, low, high.
22962 Defaults to @samp{"auto"}.
22966 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
22967 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
22969 Defaults to @samp{"auto"}.
22973 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
22974 Wifi power saving mode.
22976 Defaults to @samp{#f}.
22980 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
22981 Same as @code{wifi-power-ac?} but on BAT mode.
22983 Defaults to @samp{#t}.
22987 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
22988 Disable wake on LAN.
22990 Defaults to @samp{#t}.
22994 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
22995 Timeout duration in seconds before activating audio power saving on
22996 Intel HDA and AC97 devices. A value of 0 disables power saving.
22998 Defaults to @samp{0}.
23002 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
23003 Same as @code{sound-powersave-ac} but on BAT mode.
23005 Defaults to @samp{1}.
23009 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
23010 Disable controller in powersaving mode on Intel HDA devices.
23012 Defaults to @samp{#t}.
23016 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
23017 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
23018 powered on again by releasing (and reinserting) the eject lever or by
23019 pressing the disc eject button on newer models.
23021 Defaults to @samp{#f}.
23025 @deftypevr {@code{tlp-configuration} parameter} string bay-device
23026 Name of the optical drive device to power off.
23028 Defaults to @samp{"sr0"}.
23032 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
23033 Runtime Power Management for PCI(e) bus devices. Alternatives are on
23036 Defaults to @samp{"on"}.
23040 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
23041 Same as @code{runtime-pm-ac} but on BAT mode.
23043 Defaults to @samp{"auto"}.
23047 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
23048 Runtime Power Management for all PCI(e) bus devices, except blacklisted
23051 Defaults to @samp{#t}.
23055 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
23056 Exclude specified PCI(e) device addresses from Runtime Power Management.
23058 Defaults to @samp{disabled}.
23062 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
23063 Exclude PCI(e) devices assigned to the specified drivers from Runtime
23068 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
23069 Enable USB autosuspend feature.
23071 Defaults to @samp{#t}.
23075 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
23076 Exclude specified devices from USB autosuspend.
23078 Defaults to @samp{disabled}.
23082 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
23083 Exclude WWAN devices from USB autosuspend.
23085 Defaults to @samp{#t}.
23089 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
23090 Include specified devices into USB autosuspend, even if they are already
23091 excluded by the driver or via @code{usb-blacklist-wwan?}.
23093 Defaults to @samp{disabled}.
23097 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
23098 Enable USB autosuspend before shutdown.
23100 Defaults to @samp{disabled}.
23104 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
23105 Restore radio device state (bluetooth, wifi, wwan) from previous
23106 shutdown on system startup.
23108 Defaults to @samp{#f}.
23113 @cindex CPU frequency scaling with thermald
23114 @subsubheading Thermald daemon
23116 The @code{(gnu services pm)} module provides an interface to
23117 thermald, a CPU frequency scaling service which helps prevent overheating.
23119 @defvr {Scheme Variable} thermald-service-type
23120 This is the service type for
23121 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
23122 Thermal Daemon, which is responsible for controlling the thermal state
23123 of processors and preventing overheating.
23126 @deftp {Data Type} thermald-configuration
23127 Data type representing the configuration of @code{thermald-service-type}.
23130 @item @code{ignore-cpuid-check?} (default: @code{#f})
23131 Ignore cpuid check for supported CPU models.
23133 @item @code{thermald} (default: @var{thermald})
23134 Package object of thermald.
23139 @node Audio Services
23140 @subsection Audio Services
23142 The @code{(gnu services audio)} module provides a service to start MPD
23143 (the Music Player Daemon).
23146 @subsubheading Music Player Daemon
23148 The Music Player Daemon (MPD) is a service that can play music while
23149 being controlled from the local machine or over the network by a variety
23152 The following example shows how one might run @code{mpd} as user
23153 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
23156 (service mpd-service-type
23162 @defvr {Scheme Variable} mpd-service-type
23163 The service type for @command{mpd}
23166 @deftp {Data Type} mpd-configuration
23167 Data type representing the configuration of @command{mpd}.
23170 @item @code{user} (default: @code{"mpd"})
23171 The user to run mpd as.
23173 @item @code{music-dir} (default: @code{"~/Music"})
23174 The directory to scan for music files.
23176 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
23177 The directory to store playlists.
23179 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
23180 The location of the music database.
23182 @item @code{state-file} (default: @code{"~/.mpd/state"})
23183 The location of the file that stores current MPD's state.
23185 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
23186 The location of the sticker database.
23188 @item @code{port} (default: @code{"6600"})
23189 The port to run mpd on.
23191 @item @code{address} (default: @code{"any"})
23192 The address that mpd will bind to. To use a Unix domain socket,
23193 an absolute path can be specified here.
23195 @item @code{outputs} (default: @code{"(list (mpd-output))"})
23196 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
23201 @deftp {Data Type} mpd-output
23202 Data type representing an @command{mpd} audio output.
23205 @item @code{name} (default: @code{"MPD"})
23206 The name of the audio output.
23208 @item @code{type} (default: @code{"pulse"})
23209 The type of audio output.
23211 @item @code{enabled?} (default: @code{#t})
23212 Specifies whether this audio output is enabled when MPD is started. By
23213 default, all audio outputs are enabled. This is just the default
23214 setting when there is no state file; with a state file, the previous
23217 @item @code{tags?} (default: @code{#t})
23218 If set to @code{#f}, then MPD will not send tags to this output. This
23219 is only useful for output plugins that can receive tags, for example the
23220 @code{httpd} output plugin.
23222 @item @code{always-on?} (default: @code{#f})
23223 If set to @code{#t}, then MPD attempts to keep this audio output always
23224 open. This may be useful for streaming servers, when you don’t want to
23225 disconnect all listeners even when playback is accidentally stopped.
23227 @item @code{mixer-type}
23228 This field accepts a symbol that specifies which mixer should be used
23229 for this audio output: the @code{hardware} mixer, the @code{software}
23230 mixer, the @code{null} mixer (allows setting the volume, but with no
23231 effect; this can be used as a trick to implement an external mixer
23232 External Mixer) or no mixer (@code{none}).
23234 @item @code{extra-options} (default: @code{'()"})
23235 An association list of option symbols to string values to be appended to
23236 the audio output configuration.
23241 The following example shows a configuration of @code{mpd} that provides
23242 an HTTP audio streaming output.
23245 (service mpd-service-type
23253 `((encoder . "vorbis")
23254 (port . "8080"))))))))
23258 @node Virtualization Services
23259 @subsection Virtualization services
23261 The @code{(gnu services virtualization)} module provides services for
23262 the libvirt and virtlog daemons, as well as other virtualization-related
23265 @subsubheading Libvirt daemon
23266 @code{libvirtd} is the server side daemon component of the libvirt
23267 virtualization management system. This daemon runs on host servers
23268 and performs required management tasks for virtualized guests.
23270 @deffn {Scheme Variable} libvirt-service-type
23271 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
23272 Its value must be a @code{libvirt-configuration}.
23275 (service libvirt-service-type
23276 (libvirt-configuration
23277 (unix-sock-group "libvirt")
23278 (tls-port "16555")))
23282 @c Auto-generated with (generate-libvirt-documentation)
23283 Available @code{libvirt-configuration} fields are:
23285 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
23290 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
23291 Flag listening for secure TLS connections on the public TCP/IP port.
23292 must set @code{listen} for this to have any effect.
23294 It is necessary to setup a CA and issue server certificates before using
23297 Defaults to @samp{#t}.
23301 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
23302 Listen for unencrypted TCP connections on the public TCP/IP port. must
23303 set @code{listen} for this to have any effect.
23305 Using the TCP socket requires SASL authentication by default. Only SASL
23306 mechanisms which support data encryption are allowed. This is
23307 DIGEST_MD5 and GSSAPI (Kerberos5)
23309 Defaults to @samp{#f}.
23313 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
23314 Port for accepting secure TLS connections This can be a port number, or
23317 Defaults to @samp{"16514"}.
23321 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
23322 Port for accepting insecure TCP connections This can be a port number,
23325 Defaults to @samp{"16509"}.
23329 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
23330 IP address or hostname used for client connections.
23332 Defaults to @samp{"0.0.0.0"}.
23336 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
23337 Flag toggling mDNS advertisement of the libvirt service.
23339 Alternatively can disable for all services on a host by stopping the
23342 Defaults to @samp{#f}.
23346 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
23347 Default mDNS advertisement name. This must be unique on the immediate
23350 Defaults to @samp{"Virtualization Host <hostname>"}.
23354 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
23355 UNIX domain socket group ownership. This can be used to allow a
23356 'trusted' set of users access to management capabilities without
23359 Defaults to @samp{"root"}.
23363 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
23364 UNIX socket permissions for the R/O socket. This is used for monitoring
23367 Defaults to @samp{"0777"}.
23371 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
23372 UNIX socket permissions for the R/W socket. Default allows only root.
23373 If PolicyKit is enabled on the socket, the default will change to allow
23374 everyone (eg, 0777)
23376 Defaults to @samp{"0770"}.
23380 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
23381 UNIX socket permissions for the admin socket. Default allows only owner
23382 (root), do not change it unless you are sure to whom you are exposing
23385 Defaults to @samp{"0777"}.
23389 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
23390 The directory in which sockets will be found/created.
23392 Defaults to @samp{"/var/run/libvirt"}.
23396 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
23397 Authentication scheme for UNIX read-only sockets. By default socket
23398 permissions allow anyone to connect
23400 Defaults to @samp{"polkit"}.
23404 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
23405 Authentication scheme for UNIX read-write sockets. By default socket
23406 permissions only allow root. If PolicyKit support was compiled into
23407 libvirt, the default will be to use 'polkit' auth.
23409 Defaults to @samp{"polkit"}.
23413 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
23414 Authentication scheme for TCP sockets. If you don't enable SASL, then
23415 all TCP traffic is cleartext. Don't do this outside of a dev/test
23418 Defaults to @samp{"sasl"}.
23422 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
23423 Authentication scheme for TLS sockets. TLS sockets already have
23424 encryption provided by the TLS layer, and limited authentication is done
23427 It is possible to make use of any SASL authentication mechanism as well,
23428 by using 'sasl' for this option
23430 Defaults to @samp{"none"}.
23434 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
23435 API access control scheme.
23437 By default an authenticated user is allowed access to all APIs. Access
23438 drivers can place restrictions on this.
23440 Defaults to @samp{()}.
23444 @deftypevr {@code{libvirt-configuration} parameter} string key-file
23445 Server key file path. If set to an empty string, then no private key is
23448 Defaults to @samp{""}.
23452 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
23453 Server key file path. If set to an empty string, then no certificate is
23456 Defaults to @samp{""}.
23460 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
23461 Server key file path. If set to an empty string, then no CA certificate
23464 Defaults to @samp{""}.
23468 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
23469 Certificate revocation list path. If set to an empty string, then no
23472 Defaults to @samp{""}.
23476 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
23477 Disable verification of our own server certificates.
23479 When libvirtd starts it performs some sanity checks against its own
23482 Defaults to @samp{#f}.
23486 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
23487 Disable verification of client certificates.
23489 Client certificate verification is the primary authentication mechanism.
23490 Any client which does not present a certificate signed by the CA will be
23493 Defaults to @samp{#f}.
23497 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
23498 Whitelist of allowed x509 Distinguished Name.
23500 Defaults to @samp{()}.
23504 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
23505 Whitelist of allowed SASL usernames. The format for username depends on
23506 the SASL authentication mechanism.
23508 Defaults to @samp{()}.
23512 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
23513 Override the compile time default TLS priority string. The default is
23514 usually "NORMAL" unless overridden at build time. Only set this is it
23515 is desired for libvirt to deviate from the global default settings.
23517 Defaults to @samp{"NORMAL"}.
23521 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
23522 Maximum number of concurrent client connections to allow over all
23525 Defaults to @samp{5000}.
23529 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
23530 Maximum length of queue of connections waiting to be accepted by the
23531 daemon. Note, that some protocols supporting retransmission may obey
23532 this so that a later reattempt at connection succeeds.
23534 Defaults to @samp{1000}.
23538 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
23539 Maximum length of queue of accepted but not yet authenticated clients.
23540 Set this to zero to turn this feature off
23542 Defaults to @samp{20}.
23546 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
23547 Number of workers to start up initially.
23549 Defaults to @samp{5}.
23553 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
23554 Maximum number of worker threads.
23556 If the number of active clients exceeds @code{min-workers}, then more
23557 threads are spawned, up to max_workers limit. Typically you'd want
23558 max_workers to equal maximum number of clients allowed.
23560 Defaults to @samp{20}.
23564 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
23565 Number of priority workers. If all workers from above pool are stuck,
23566 some calls marked as high priority (notably domainDestroy) can be
23567 executed in this pool.
23569 Defaults to @samp{5}.
23573 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
23574 Total global limit on concurrent RPC calls.
23576 Defaults to @samp{20}.
23580 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
23581 Limit on concurrent requests from a single client connection. To avoid
23582 one client monopolizing the server this should be a small fraction of
23583 the global max_requests and max_workers parameter.
23585 Defaults to @samp{5}.
23589 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
23590 Same as @code{min-workers} but for the admin interface.
23592 Defaults to @samp{1}.
23596 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
23597 Same as @code{max-workers} but for the admin interface.
23599 Defaults to @samp{5}.
23603 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
23604 Same as @code{max-clients} but for the admin interface.
23606 Defaults to @samp{5}.
23610 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
23611 Same as @code{max-queued-clients} but for the admin interface.
23613 Defaults to @samp{5}.
23617 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
23618 Same as @code{max-client-requests} but for the admin interface.
23620 Defaults to @samp{5}.
23624 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
23625 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
23627 Defaults to @samp{3}.
23631 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
23634 A filter allows to select a different logging level for a given category
23635 of logs The format for a filter is one of:
23646 where @code{name} is a string which is matched against the category
23647 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
23648 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
23649 be a substring of the full category name, in order to match multiple
23650 similar categories), the optional "+" prefix tells libvirt to log stack
23651 trace for each message matching name, and @code{x} is the minimal level
23652 where matching messages should be logged:
23669 Multiple filters can be defined in a single filters statement, they just
23670 need to be separated by spaces.
23672 Defaults to @samp{"3:remote 4:event"}.
23676 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
23679 An output is one of the places to save logging information. The format
23680 for an output can be:
23684 output goes to stderr
23686 @item x:syslog:name
23687 use syslog for the output and use the given name as the ident
23689 @item x:file:file_path
23690 output to a file, with the given filepath
23693 output to journald logging system
23697 In all case the x prefix is the minimal level, acting as a filter
23714 Multiple outputs can be defined, they just need to be separated by
23717 Defaults to @samp{"3:stderr"}.
23721 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
23722 Allows usage of the auditing subsystem to be altered
23726 0: disable all auditing
23729 1: enable auditing, only if enabled on host
23732 2: enable auditing, and exit if disabled on host.
23736 Defaults to @samp{1}.
23740 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
23741 Send audit messages via libvirt logging infrastructure.
23743 Defaults to @samp{#f}.
23747 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
23748 Host UUID. UUID must not have all digits be the same.
23750 Defaults to @samp{""}.
23754 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
23755 Source to read host UUID.
23759 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
23762 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
23766 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
23769 Defaults to @samp{"smbios"}.
23773 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
23774 A keepalive message is sent to a client after @code{keepalive_interval}
23775 seconds of inactivity to check if the client is still responding. If
23776 set to -1, libvirtd will never send keepalive requests; however clients
23777 can still send them and the daemon will send responses.
23779 Defaults to @samp{5}.
23783 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
23784 Maximum number of keepalive messages that are allowed to be sent to the
23785 client without getting any response before the connection is considered
23788 In other words, the connection is automatically closed approximately
23789 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
23790 the last message received from the client. When @code{keepalive-count}
23791 is set to 0, connections will be automatically closed after
23792 @code{keepalive-interval} seconds of inactivity without sending any
23793 keepalive messages.
23795 Defaults to @samp{5}.
23799 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
23800 Same as above but for admin interface.
23802 Defaults to @samp{5}.
23806 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
23807 Same as above but for admin interface.
23809 Defaults to @samp{5}.
23813 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
23814 Timeout for Open vSwitch calls.
23816 The @code{ovs-vsctl} utility is used for the configuration and its
23817 timeout option is set by default to 5 seconds to avoid potential
23818 infinite waits blocking libvirt.
23820 Defaults to @samp{5}.
23824 @c %end of autogenerated docs
23826 @subsubheading Virtlog daemon
23827 The virtlogd service is a server side daemon component of libvirt that is
23828 used to manage logs from virtual machine consoles.
23830 This daemon is not used directly by libvirt client applications, rather it
23831 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
23832 standalone daemon, the main @code{libvirtd} daemon can be restarted without
23833 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
23834 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
23836 @deffn {Scheme Variable} virtlog-service-type
23837 This is the type of the virtlog daemon.
23838 Its value must be a @code{virtlog-configuration}.
23841 (service virtlog-service-type
23842 (virtlog-configuration
23843 (max-clients 1000)))
23847 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
23848 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
23850 Defaults to @samp{3}.
23854 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
23857 A filter allows to select a different logging level for a given category
23858 of logs The format for a filter is one of:
23869 where @code{name} is a string which is matched against the category
23870 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
23871 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
23872 be a substring of the full category name, in order to match multiple
23873 similar categories), the optional "+" prefix tells libvirt to log stack
23874 trace for each message matching name, and @code{x} is the minimal level
23875 where matching messages should be logged:
23892 Multiple filters can be defined in a single filters statement, they just
23893 need to be separated by spaces.
23895 Defaults to @samp{"3:remote 4:event"}.
23899 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
23902 An output is one of the places to save logging information The format
23903 for an output can be:
23907 output goes to stderr
23909 @item x:syslog:name
23910 use syslog for the output and use the given name as the ident
23912 @item x:file:file_path
23913 output to a file, with the given filepath
23916 output to journald logging system
23920 In all case the x prefix is the minimal level, acting as a filter
23937 Multiple outputs can be defined, they just need to be separated by
23940 Defaults to @samp{"3:stderr"}.
23944 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
23945 Maximum number of concurrent client connections to allow over all
23948 Defaults to @samp{1024}.
23952 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
23953 Maximum file size before rolling over.
23955 Defaults to @samp{2MB}
23959 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
23960 Maximum number of backup files to keep.
23962 Defaults to @samp{3}
23966 @subsubheading Transparent Emulation with QEMU
23969 @cindex @code{binfmt_misc}
23970 @code{qemu-binfmt-service-type} provides support for transparent
23971 emulation of program binaries built for different architectures---e.g.,
23972 it allows you to transparently execute an ARMv7 program on an x86_64
23973 machine. It achieves this by combining the @uref{https://www.qemu.org,
23974 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
23976 @defvr {Scheme Variable} qemu-binfmt-service-type
23977 This is the type of the QEMU/binfmt service for transparent emulation.
23978 Its value must be a @code{qemu-binfmt-configuration} object, which
23979 specifies the QEMU package to use as well as the architecture we want to
23983 (service qemu-binfmt-service-type
23984 (qemu-binfmt-configuration
23985 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
23988 In this example, we enable transparent emulation for the ARM and aarch64
23989 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
23990 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
23991 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
23994 @deftp {Data Type} qemu-binfmt-configuration
23995 This is the configuration for the @code{qemu-binfmt} service.
23998 @item @code{platforms} (default: @code{'()})
23999 The list of emulated QEMU platforms. Each item must be a @dfn{platform
24000 object} as returned by @code{lookup-qemu-platforms} (see below).
24002 @item @code{guix-support?} (default: @code{#f})
24003 When it is true, QEMU and all its dependencies are added to the build
24004 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
24005 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
24006 handlers to be used within the build environment, which in turn means
24007 that you can transparently build programs for another architecture.
24009 For example, let's suppose you're on an x86_64 machine and you have this
24013 (service qemu-binfmt-service-type
24014 (qemu-binfmt-configuration
24015 (platforms (lookup-qemu-platforms "arm"))
24016 (guix-support? #t)))
24022 guix build -s armhf-linux inkscape
24026 and it will build Inkscape for ARMv7 @emph{as if it were a native
24027 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
24028 if you'd like to test a package build for an architecture you don't have
24031 @item @code{qemu} (default: @code{qemu})
24032 The QEMU package to use.
24036 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
24037 Return the list of QEMU platform objects corresponding to
24038 @var{platforms}@dots{}. @var{platforms} must be a list of strings
24039 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
24040 @code{"mips64el"}, and so on.
24043 @deffn {Scheme Procedure} qemu-platform? @var{obj}
24044 Return true if @var{obj} is a platform object.
24047 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
24048 Return the name of @var{platform}---a string such as @code{"arm"}.
24051 @node Version Control Services
24052 @subsection Version Control Services
24054 The @code{(gnu services version-control)} module provides a service to
24055 allow remote access to local Git repositories. There are three options:
24056 the @code{git-daemon-service}, which provides access to repositories via
24057 the @code{git://} unsecured TCP-based protocol, extending the
24058 @code{nginx} web server to proxy some requests to
24059 @code{git-http-backend}, or providing a web interface with
24060 @code{cgit-service-type}.
24062 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
24064 Return a service that runs @command{git daemon}, a simple TCP server to
24065 expose repositories over the Git protocol for anonymous access.
24067 The optional @var{config} argument should be a
24068 @code{<git-daemon-configuration>} object, by default it allows read-only
24069 access to exported@footnote{By creating the magic file
24070 "git-daemon-export-ok" in the repository directory.} repositories under
24075 @deftp {Data Type} git-daemon-configuration
24076 Data type representing the configuration for @code{git-daemon-service}.
24079 @item @code{package} (default: @var{git})
24080 Package object of the Git distributed version control system.
24082 @item @code{export-all?} (default: @var{#f})
24083 Whether to allow access for all Git repositories, even if they do not
24084 have the @file{git-daemon-export-ok} file.
24086 @item @code{base-path} (default: @file{/srv/git})
24087 Whether to remap all the path requests as relative to the given path.
24088 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
24089 then if you later try to pull @code{git://example.com/hello.git}, git
24090 daemon will interpret the path as @code{/srv/git/hello.git}.
24092 @item @code{user-path} (default: @var{#f})
24093 Whether to allow @code{~user} notation to be used in requests. When
24094 specified with empty string, requests to @code{git://host/~alice/foo} is
24095 taken as a request to access @code{foo} repository in the home directory
24096 of user @code{alice}. If @var{(user-path "path")} is specified, the
24097 same request is taken as a request to access @code{path/foo} repository
24098 in the home directory of user @code{alice}.
24100 @item @code{listen} (default: @var{'()})
24101 Whether to listen on specific IP addresses or hostnames, defaults to
24104 @item @code{port} (default: @var{#f})
24105 Whether to listen on an alternative port, which defaults to 9418.
24107 @item @code{whitelist} (default: @var{'()})
24108 If not empty, only allow access to this list of directories.
24110 @item @code{extra-options} (default: @var{'()})
24111 Extra options will be passed to @code{git daemon}, please run
24112 @command{man git-daemon} for more information.
24117 The @code{git://} protocol lacks authentication. When you pull from a
24118 repository fetched via @code{git://}, you don't know whether the data you
24119 receive was modified or is even coming from the specified host, and your
24120 connection is subject to eavesdropping. It's better to use an authenticated
24121 and encrypted transport, such as @code{https}. Although Git allows you
24122 to serve repositories using unsophisticated file-based web servers,
24123 there is a faster protocol implemented by the @code{git-http-backend}
24124 program. This program is the back-end of a proper Git web service. It
24125 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
24126 on running the necessary @code{fcgiwrap} daemon.
24128 Guix has a separate configuration data type for serving Git repositories
24131 @deftp {Data Type} git-http-configuration
24132 Data type representing the configuration for @code{git-http-service}.
24135 @item @code{package} (default: @var{git})
24136 Package object of the Git distributed version control system.
24138 @item @code{git-root} (default: @file{/srv/git})
24139 Directory containing the Git repositories to expose to the world.
24141 @item @code{export-all?} (default: @var{#f})
24142 Whether to expose access for all Git repositories in @var{git-root},
24143 even if they do not have the @file{git-daemon-export-ok} file.
24145 @item @code{uri-path} (default: @file{/git/})
24146 Path prefix for Git access. With the default @code{/git/} prefix, this
24147 will map @code{http://@var{server}/git/@var{repo}.git} to
24148 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
24149 with this prefix are not passed on to this Git instance.
24151 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
24152 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
24157 There is no @code{git-http-service-type}, currently; instead you can
24158 create an @code{nginx-location-configuration} from a
24159 @code{git-http-configuration} and then add that location to a web
24162 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
24163 [config=(git-http-configuration)]
24164 Compute an @code{nginx-location-configuration} that corresponds to the
24165 given Git http configuration. An example nginx service definition to
24166 serve the default @file{/srv/git} over HTTPS might be:
24169 (service nginx-service-type
24170 (nginx-configuration
24173 (nginx-server-configuration
24174 (listen '("443 ssl"))
24175 (server-name "git.my-host.org")
24177 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
24178 (ssl-certificate-key
24179 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
24182 (git-http-nginx-location-configuration
24183 (git-http-configuration (uri-path "/"))))))))))
24186 This example assumes that you are using Let's Encrypt to get your TLS
24187 certificate. @xref{Certificate Services}. The default @code{certbot}
24188 service will redirect all HTTP traffic on @code{git.my-host.org} to
24189 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
24190 system services. @xref{Web Services}.
24193 @subsubheading Cgit Service
24195 @cindex Cgit service
24196 @cindex Git, web interface
24197 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
24198 repositories written in C.
24200 The following example will configure the service with default values.
24201 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
24204 (service cgit-service-type)
24207 The @code{file-object} type designates either a file-like object
24208 (@pxref{G-Expressions, file-like objects}) or a string.
24210 @c %start of fragment
24212 Available @code{cgit-configuration} fields are:
24214 @deftypevr {@code{cgit-configuration} parameter} package package
24219 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
24220 NGINX configuration.
24224 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
24225 Specifies a command which will be invoked to format the content of about
24226 pages (both top-level and for each repository).
24228 Defaults to @samp{""}.
24232 @deftypevr {@code{cgit-configuration} parameter} string agefile
24233 Specifies a path, relative to each repository path, which can be used to
24234 specify the date and time of the youngest commit in the repository.
24236 Defaults to @samp{""}.
24240 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
24241 Specifies a command that will be invoked for authenticating repository
24244 Defaults to @samp{""}.
24248 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
24249 Flag which, when set to @samp{age}, enables date ordering in the branch
24250 ref list, and when set @samp{name} enables ordering by branch name.
24252 Defaults to @samp{"name"}.
24256 @deftypevr {@code{cgit-configuration} parameter} string cache-root
24257 Path used to store the cgit cache entries.
24259 Defaults to @samp{"/var/cache/cgit"}.
24263 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
24264 Number which specifies the time-to-live, in minutes, for the cached
24265 version of repository pages accessed with a fixed SHA1.
24267 Defaults to @samp{-1}.
24271 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
24272 Number which specifies the time-to-live, in minutes, for the cached
24273 version of repository pages accessed without a fixed SHA1.
24275 Defaults to @samp{5}.
24279 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
24280 Number which specifies the time-to-live, in minutes, for the cached
24281 version of the repository summary page.
24283 Defaults to @samp{5}.
24287 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
24288 Number which specifies the time-to-live, in minutes, for the cached
24289 version of the repository index page.
24291 Defaults to @samp{5}.
24295 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
24296 Number which specifies the time-to-live, in minutes, for the result of
24297 scanning a path for Git repositories.
24299 Defaults to @samp{15}.
24303 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
24304 Number which specifies the time-to-live, in minutes, for the cached
24305 version of the repository about page.
24307 Defaults to @samp{15}.
24311 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
24312 Number which specifies the time-to-live, in minutes, for the cached
24313 version of snapshots.
24315 Defaults to @samp{5}.
24319 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
24320 The maximum number of entries in the cgit cache. When set to @samp{0},
24321 caching is disabled.
24323 Defaults to @samp{0}.
24327 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
24328 Sort items in the repo list case sensitively.
24330 Defaults to @samp{#t}.
24334 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
24335 List of common prefixes which, when combined with a repository URL,
24336 generates valid clone URLs for the repository.
24338 Defaults to @samp{()}.
24342 @deftypevr {@code{cgit-configuration} parameter} list clone-url
24343 List of @code{clone-url} templates.
24345 Defaults to @samp{()}.
24349 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
24350 Command which will be invoked to format commit messages.
24352 Defaults to @samp{""}.
24356 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
24357 Flag which, when set to @samp{date}, enables strict date ordering in the
24358 commit log, and when set to @samp{topo} enables strict topological
24361 Defaults to @samp{"git log"}.
24365 @deftypevr {@code{cgit-configuration} parameter} file-object css
24366 URL which specifies the css document to include in all cgit pages.
24368 Defaults to @samp{"/share/cgit/cgit.css"}.
24372 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
24373 Specifies a command which will be invoked to format names and email
24374 address of committers, authors, and taggers, as represented in various
24375 places throughout the cgit interface.
24377 Defaults to @samp{""}.
24381 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
24382 Flag which, when set to @samp{#t}, will make cgit generate a HTML
24383 fragment suitable for embedding in other HTML pages.
24385 Defaults to @samp{#f}.
24389 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
24390 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
24391 commit history graph to the left of the commit messages in the
24392 repository log page.
24394 Defaults to @samp{#f}.
24398 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
24399 Flag which, when set to @samp{#t}, allows all filter settings to be
24400 overridden in repository-specific cgitrc files.
24402 Defaults to @samp{#f}.
24406 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
24407 Flag which, when set to @samp{#t}, allows users to follow a file in the
24410 Defaults to @samp{#f}.
24414 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
24415 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
24418 Defaults to @samp{#t}.
24422 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
24423 Flag which, when set to @samp{#t}, will make cgit generate extra links
24424 "summary", "commit", "tree" for each repo in the repository index.
24426 Defaults to @samp{#f}.
24430 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
24431 Flag which, when set to @samp{#t}, will make cgit display the owner of
24432 each repo in the repository index.
24434 Defaults to @samp{#t}.
24438 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
24439 Flag which, when set to @samp{#t}, will make cgit print the number of
24440 modified files for each commit on the repository log page.
24442 Defaults to @samp{#f}.
24446 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
24447 Flag which, when set to @samp{#t}, will make cgit print the number of
24448 added and removed lines for each commit on the repository log page.
24450 Defaults to @samp{#f}.
24454 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
24455 Flag which, when set to @code{#t}, will make cgit display remote
24456 branches in the summary and refs views.
24458 Defaults to @samp{#f}.
24462 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
24463 Flag which, when set to @code{1}, will make cgit use the subject of the
24464 parent commit as link text when generating links to parent commits in
24467 Defaults to @samp{#f}.
24471 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
24472 Flag which, when set to @samp{#t}, will make cgit use the subject of the
24473 parent commit as link text when generating links to parent commits in
24476 Defaults to @samp{#f}.
24480 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
24481 Flag which, when set to @samp{#t}, will make cgit generate linenumber
24482 links for plaintext blobs printed in the tree view.
24484 Defaults to @samp{#t}.
24488 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
24489 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
24490 set any repo specific settings.
24492 Defaults to @samp{#f}.
24496 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
24497 URL used as link to a shortcut icon for cgit.
24499 Defaults to @samp{"/favicon.ico"}.
24503 @deftypevr {@code{cgit-configuration} parameter} string footer
24504 The content of the file specified with this option will be included
24505 verbatim at the bottom of all pages (i.e.@: it replaces the standard
24506 "generated by..."@: message).
24508 Defaults to @samp{""}.
24512 @deftypevr {@code{cgit-configuration} parameter} string head-include
24513 The content of the file specified with this option will be included
24514 verbatim in the HTML HEAD section on all pages.
24516 Defaults to @samp{""}.
24520 @deftypevr {@code{cgit-configuration} parameter} string header
24521 The content of the file specified with this option will be included
24522 verbatim at the top of all pages.
24524 Defaults to @samp{""}.
24528 @deftypevr {@code{cgit-configuration} parameter} file-object include
24529 Name of a configfile to include before the rest of the current config-
24532 Defaults to @samp{""}.
24536 @deftypevr {@code{cgit-configuration} parameter} string index-header
24537 The content of the file specified with this option will be included
24538 verbatim above the repository index.
24540 Defaults to @samp{""}.
24544 @deftypevr {@code{cgit-configuration} parameter} string index-info
24545 The content of the file specified with this option will be included
24546 verbatim below the heading on the repository index page.
24548 Defaults to @samp{""}.
24552 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
24553 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
24554 in the servers timezone.
24556 Defaults to @samp{#f}.
24560 @deftypevr {@code{cgit-configuration} parameter} file-object logo
24561 URL which specifies the source of an image which will be used as a logo
24564 Defaults to @samp{"/share/cgit/cgit.png"}.
24568 @deftypevr {@code{cgit-configuration} parameter} string logo-link
24569 URL loaded when clicking on the cgit logo image.
24571 Defaults to @samp{""}.
24575 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
24576 Command which will be invoked to format the Owner column of the main
24579 Defaults to @samp{""}.
24583 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
24584 Number of items to display in atom feeds view.
24586 Defaults to @samp{10}.
24590 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
24591 Number of entries to list per page in "log" view.
24593 Defaults to @samp{50}.
24597 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
24598 Number of commit message characters to display in "log" view.
24600 Defaults to @samp{80}.
24604 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
24605 Specifies the number of entries to list per page on the repository index
24608 Defaults to @samp{50}.
24612 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
24613 Specifies the maximum number of repo description characters to display
24614 on the repository index page.
24616 Defaults to @samp{80}.
24620 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
24621 Specifies the maximum size of a blob to display HTML for in KBytes.
24623 Defaults to @samp{0}.
24627 @deftypevr {@code{cgit-configuration} parameter} string max-stats
24628 Maximum statistics period. Valid values are @samp{week},@samp{month},
24629 @samp{quarter} and @samp{year}.
24631 Defaults to @samp{""}.
24635 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
24636 Mimetype for the specified filename extension.
24638 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
24639 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
24640 "image/png") (svg "image/svg+xml"))}.
24644 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
24645 Specifies the file to use for automatic mimetype lookup.
24647 Defaults to @samp{""}.
24651 @deftypevr {@code{cgit-configuration} parameter} string module-link
24652 Text which will be used as the formatstring for a hyperlink when a
24653 submodule is printed in a directory listing.
24655 Defaults to @samp{""}.
24659 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
24660 If set to the value @samp{#t} caching will be disabled.
24662 Defaults to @samp{#f}.
24666 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
24667 If set to @samp{#t} showing full author email addresses will be
24670 Defaults to @samp{#f}.
24674 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
24675 Flag which, when set to @samp{#t}, will make cgit omit the standard
24676 header on all pages.
24678 Defaults to @samp{#f}.
24682 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
24683 A list of subdirectories inside of @code{repository-directory}, relative
24684 to it, that should loaded as Git repositories. An empty list means that
24685 all subdirectories will be loaded.
24687 Defaults to @samp{()}.
24691 @deftypevr {@code{cgit-configuration} parameter} file-object readme
24692 Text which will be used as default value for @code{cgit-repo-readme}.
24694 Defaults to @samp{""}.
24698 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
24699 If set to @code{#t} and @code{repository-directory} is enabled, if any
24700 repositories are found with a suffix of @code{.git}, this suffix will be
24701 removed for the URL and name.
24703 Defaults to @samp{#f}.
24707 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
24708 Maximum number of files to consider when detecting renames.
24710 Defaults to @samp{-1}.
24714 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
24715 The way in which repositories in each section are sorted.
24717 Defaults to @samp{""}.
24721 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
24722 Text used as content for the @code{robots} meta-tag.
24724 Defaults to @samp{("noindex" "nofollow")}.
24728 @deftypevr {@code{cgit-configuration} parameter} string root-desc
24729 Text printed below the heading on the repository index page.
24731 Defaults to @samp{"a fast webinterface for the git dscm"}.
24735 @deftypevr {@code{cgit-configuration} parameter} string root-readme
24736 The content of the file specified with this option will be included
24737 verbatim below the "about" link on the repository index page.
24739 Defaults to @samp{""}.
24743 @deftypevr {@code{cgit-configuration} parameter} string root-title
24744 Text printed as heading on the repository index page.
24746 Defaults to @samp{""}.
24750 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
24751 If set to @samp{#t} and repository-directory is enabled,
24752 repository-directory will recurse into directories whose name starts
24753 with a period. Otherwise, repository-directory will stay away from such
24754 directories, considered as "hidden". Note that this does not apply to
24755 the ".git" directory in non-bare repos.
24757 Defaults to @samp{#f}.
24761 @deftypevr {@code{cgit-configuration} parameter} list snapshots
24762 Text which specifies the default set of snapshot formats that cgit
24763 generates links for.
24765 Defaults to @samp{()}.
24769 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
24770 Name of the directory to scan for repositories (represents
24773 Defaults to @samp{"/srv/git"}.
24777 @deftypevr {@code{cgit-configuration} parameter} string section
24778 The name of the current repository section - all repositories defined
24779 after this option will inherit the current section name.
24781 Defaults to @samp{""}.
24785 @deftypevr {@code{cgit-configuration} parameter} string section-sort
24786 Flag which, when set to @samp{1}, will sort the sections on the
24787 repository listing by name.
24789 Defaults to @samp{""}.
24793 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
24794 A number which, if defined prior to repository-directory, specifies how
24795 many path elements from each repo path to use as a default section name.
24797 Defaults to @samp{0}.
24801 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
24802 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
24805 Defaults to @samp{#f}.
24809 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
24810 Specifies a command which will be invoked to format plaintext blobs in
24813 Defaults to @samp{""}.
24817 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
24818 Specifies the number of branches to display in the repository "summary"
24821 Defaults to @samp{10}.
24825 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
24826 Specifies the number of log entries to display in the repository
24829 Defaults to @samp{10}.
24833 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
24834 Specifies the number of tags to display in the repository "summary"
24837 Defaults to @samp{10}.
24841 @deftypevr {@code{cgit-configuration} parameter} string strict-export
24842 Filename which, if specified, needs to be present within the repository
24843 for cgit to allow access to that repository.
24845 Defaults to @samp{""}.
24849 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
24850 URL which, if specified, will be used as root for all cgit links.
24852 Defaults to @samp{"/"}.
24856 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
24857 A list of @dfn{cgit-repo} records to use with config.
24859 Defaults to @samp{()}.
24861 Available @code{repository-cgit-configuration} fields are:
24863 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
24864 A mask of snapshot formats for this repo that cgit generates links for,
24865 restricted by the global @code{snapshots} setting.
24867 Defaults to @samp{()}.
24871 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
24872 Override the default @code{source-filter}.
24874 Defaults to @samp{""}.
24878 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
24879 The relative URL used to access the repository.
24881 Defaults to @samp{""}.
24885 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
24886 Override the default @code{about-filter}.
24888 Defaults to @samp{""}.
24892 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
24893 Flag which, when set to @samp{age}, enables date ordering in the branch
24894 ref list, and when set to @samp{name} enables ordering by branch name.
24896 Defaults to @samp{""}.
24900 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
24901 A list of URLs which can be used to clone repo.
24903 Defaults to @samp{()}.
24907 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
24908 Override the default @code{commit-filter}.
24910 Defaults to @samp{""}.
24914 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
24915 Flag which, when set to @samp{date}, enables strict date ordering in the
24916 commit log, and when set to @samp{topo} enables strict topological
24919 Defaults to @samp{""}.
24923 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
24924 The name of the default branch for this repository. If no such branch
24925 exists in the repository, the first branch name (when sorted) is used as
24926 default instead. By default branch pointed to by HEAD, or "master" if
24927 there is no suitable HEAD.
24929 Defaults to @samp{""}.
24933 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
24934 The value to show as repository description.
24936 Defaults to @samp{""}.
24940 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
24941 The value to show as repository homepage.
24943 Defaults to @samp{""}.
24947 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
24948 Override the default @code{email-filter}.
24950 Defaults to @samp{""}.
24954 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
24955 A flag which can be used to disable the global setting
24956 @code{enable-commit-graph?}.
24958 Defaults to @samp{disabled}.
24962 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
24963 A flag which can be used to disable the global setting
24964 @code{enable-log-filecount?}.
24966 Defaults to @samp{disabled}.
24970 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
24971 A flag which can be used to disable the global setting
24972 @code{enable-log-linecount?}.
24974 Defaults to @samp{disabled}.
24978 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
24979 Flag which, when set to @code{#t}, will make cgit display remote
24980 branches in the summary and refs views.
24982 Defaults to @samp{disabled}.
24986 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
24987 A flag which can be used to override the global setting
24988 @code{enable-subject-links?}.
24990 Defaults to @samp{disabled}.
24994 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
24995 A flag which can be used to override the global setting
24996 @code{enable-html-serving?}.
24998 Defaults to @samp{disabled}.
25002 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
25003 Flag which, when set to @code{#t}, hides the repository from the
25006 Defaults to @samp{#f}.
25010 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
25011 Flag which, when set to @samp{#t}, ignores the repository.
25013 Defaults to @samp{#f}.
25017 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
25018 URL which specifies the source of an image which will be used as a logo
25019 on this repo’s pages.
25021 Defaults to @samp{""}.
25025 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
25026 URL loaded when clicking on the cgit logo image.
25028 Defaults to @samp{""}.
25032 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
25033 Override the default @code{owner-filter}.
25035 Defaults to @samp{""}.
25039 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
25040 Text which will be used as the formatstring for a hyperlink when a
25041 submodule is printed in a directory listing. The arguments for the
25042 formatstring are the path and SHA1 of the submodule commit.
25044 Defaults to @samp{""}.
25048 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
25049 Text which will be used as the formatstring for a hyperlink when a
25050 submodule with the specified subdirectory path is printed in a directory
25053 Defaults to @samp{()}.
25057 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
25058 Override the default maximum statistics period.
25060 Defaults to @samp{""}.
25064 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
25065 The value to show as repository name.
25067 Defaults to @samp{""}.
25071 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
25072 A value used to identify the owner of the repository.
25074 Defaults to @samp{""}.
25078 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
25079 An absolute path to the repository directory.
25081 Defaults to @samp{""}.
25085 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
25086 A path (relative to repo) which specifies a file to include verbatim as
25087 the "About" page for this repo.
25089 Defaults to @samp{""}.
25093 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
25094 The name of the current repository section - all repositories defined
25095 after this option will inherit the current section name.
25097 Defaults to @samp{""}.
25101 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
25102 Extra options will be appended to cgitrc file.
25104 Defaults to @samp{()}.
25110 @deftypevr {@code{cgit-configuration} parameter} list extra-options
25111 Extra options will be appended to cgitrc file.
25113 Defaults to @samp{()}.
25118 @c %end of fragment
25120 However, it could be that you just want to get a @code{cgitrc} up and
25121 running. In that case, you can pass an @code{opaque-cgit-configuration}
25122 as a record to @code{cgit-service-type}. As its name indicates, an
25123 opaque configuration does not have easy reflective capabilities.
25125 Available @code{opaque-cgit-configuration} fields are:
25127 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
25131 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
25132 The contents of the @code{cgitrc}, as a string.
25135 For example, if your @code{cgitrc} is just the empty string, you
25136 could instantiate a cgit service like this:
25139 (service cgit-service-type
25140 (opaque-cgit-configuration
25144 @subsubheading Gitolite Service
25146 @cindex Gitolite service
25147 @cindex Git, hosting
25148 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
25149 repositories on a central server.
25151 Gitolite can handle multiple repositories and users, and supports flexible
25152 configuration of the permissions for the users on the repositories.
25154 The following example will configure Gitolite using the default @code{git}
25155 user, and the provided SSH public key.
25158 (service gitolite-service-type
25159 (gitolite-configuration
25160 (admin-pubkey (plain-file
25162 "ssh-rsa AAAA... guix@@example.com"))))
25165 Gitolite is configured through a special admin repository which you can clone,
25166 for example, if you setup Gitolite on @code{example.com}, you would run the
25167 following command to clone the admin repository.
25170 git clone git@@example.com:gitolite-admin
25173 When the Gitolite service is activated, the provided @code{admin-pubkey} will
25174 be inserted in to the @file{keydir} directory in the gitolite-admin
25175 repository. If this results in a change in the repository, it will be
25176 committed using the message ``gitolite setup by GNU Guix''.
25178 @deftp {Data Type} gitolite-configuration
25179 Data type representing the configuration for @code{gitolite-service-type}.
25182 @item @code{package} (default: @var{gitolite})
25183 Gitolite package to use.
25185 @item @code{user} (default: @var{git})
25186 User to use for Gitolite. This will be user that you use when accessing
25189 @item @code{group} (default: @var{git})
25190 Group to use for Gitolite.
25192 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
25193 Directory in which to store the Gitolite configuration and repositories.
25195 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
25196 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
25197 representing the configuration for Gitolite.
25199 @item @code{admin-pubkey} (default: @var{#f})
25200 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
25201 setup Gitolite. This will be inserted in to the @file{keydir} directory
25202 within the gitolite-admin repository.
25204 To specify the SSH key as a string, use the @code{plain-file} function.
25207 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
25213 @deftp {Data Type} gitolite-rc-file
25214 Data type representing the Gitolite RC file.
25217 @item @code{umask} (default: @code{#o0077})
25218 This controls the permissions Gitolite sets on the repositories and their
25221 A value like @code{#o0027} will give read access to the group used by Gitolite
25222 (by default: @code{git}). This is necessary when using Gitolite with software
25223 like cgit or gitweb.
25225 @item @code{git-config-keys} (default: @code{""})
25226 Gitolite allows you to set git config values using the "config" keyword. This
25227 setting allows control over the config keys to accept.
25229 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
25230 Set the role names allowed to be used by users running the perms command.
25232 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
25233 This setting controls the commands and features to enable within Gitolite.
25239 @node Game Services
25240 @subsection Game Services
25242 @subsubheading The Battle for Wesnoth Service
25244 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
25245 based tactical strategy game, with several single player campaigns, and
25246 multiplayer games (both networked and local).
25248 @defvar {Scheme Variable} wesnothd-service-type
25249 Service type for the wesnothd service. Its value must be a
25250 @code{wesnothd-configuration} object. To run wesnothd in the default
25251 configuration, instantiate it as:
25254 (service wesnothd-service-type)
25258 @deftp {Data Type} wesnothd-configuration
25259 Data type representing the configuration of @command{wesnothd}.
25262 @item @code{package} (default: @code{wesnoth-server})
25263 The wesnoth server package to use.
25265 @item @code{port} (default: @code{15000})
25266 The port to bind the server to.
25271 @node PAM Mount Service
25272 @subsection PAM Mount Service
25275 The @code{(gnu services pam-mount)} module provides a service allowing
25276 users to mount volumes when they log in. It should be able to mount any
25277 volume format supported by the system.
25279 @defvar {Scheme Variable} pam-mount-service-type
25280 Service type for PAM Mount support.
25283 @deftp {Data Type} pam-mount-configuration
25284 Data type representing the configuration of PAM Mount.
25286 It takes the following parameters:
25290 The configuration rules that will be used to generate
25291 @file{/etc/security/pam_mount.conf.xml}.
25293 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
25294 Guile Reference Manual}), and the the default ones don't mount anything
25295 for anyone at login:
25298 `((debug (@@ (enable "0")))
25299 (mntoptions (@@ (allow ,(string-join
25300 '("nosuid" "nodev" "loop"
25301 "encryption" "fsck" "nonempty"
25302 "allow_root" "allow_other")
25304 (mntoptions (@@ (require "nosuid,nodev")))
25305 (logout (@@ (wait "0")
25309 (mkmountpoint (@@ (enable "1")
25313 Some @code{volume} elements must be added to automatically mount volumes
25314 at login. Here's an example allowing the user @code{alice} to mount her
25315 encrypted @code{HOME} directory and allowing the user @code{bob} to mount
25316 the partition where he stores his data:
25319 (define pam-mount-rules
25320 `((debug (@@ (enable "0")))
25321 (volume (@@ (user "alice")
25324 (mountpoint "/home/alice")))
25325 (volume (@@ (user "bob")
25328 (mountpoint "/home/bob/data")
25329 (options "defaults,autodefrag,compress")))
25330 (mntoptions (@@ (allow ,(string-join
25331 '("nosuid" "nodev" "loop"
25332 "encryption" "fsck" "nonempty"
25333 "allow_root" "allow_other")
25335 (mntoptions (@@ (require "nosuid,nodev")))
25336 (logout (@@ (wait "0")
25340 (mkmountpoint (@@ (enable "1")
25341 (remove "true")))))
25343 (service pam-mount-service-type
25344 (pam-mount-configuration
25345 (rules pam-mount-rules)))
25348 The complete list of possible options can be found in the man page for
25349 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
25354 @node Guix Services
25355 @subsection Guix Services
25357 @subsubheading Guix Data Service
25358 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
25359 and provides data about GNU Guix. This includes information about
25360 packages, derivations and lint warnings.
25362 The data is stored in a PostgreSQL database, and available through a web
25365 @defvar {Scheme Variable} guix-data-service-type
25366 Service type for the Guix Data Service. Its value must be a
25367 @code{guix-data-service-configuration} object. The service optionally
25368 extends the getmail service, as the guix-commits mailing list is used to
25369 find out about changes in the Guix git repository.
25372 @deftp {Data Type} guix-data-service-configuration
25373 Data type representing the configuration of the Guix Data Service.
25376 @item @code{package} (default: @code{guix-data-service})
25377 The Guix Data Service package to use.
25379 @item @code{user} (default: @code{"guix-data-service"})
25380 The system user to run the service as.
25382 @item @code{group} (default: @code{"guix-data-service"})
25383 The system group to run the service as.
25385 @item @code{port} (default: @code{8765})
25386 The port to bind the web service to.
25388 @item @code{host} (default: @code{"127.0.0.1"})
25389 The host to bind the web service to.
25391 @item @code{getmail-idle-mailboxes} (default: @code{#f})
25392 If set, this is the list of mailboxes that the getmail service will be
25393 configured to listen to.
25395 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
25396 If set, this is the @code{getmail-retriever-configuration} object with
25397 which to configure getmail to fetch mail from the guix-commits mailing
25400 @item @code{extra-options} (default: @var{'()})
25401 Extra command line options for @code{guix-data-service}.
25403 @item @code{extra-process-jobs-options} (default: @var{'()})
25404 Extra command line options for @code{guix-data-service-process-jobs}.
25409 @node Linux Services
25410 @subsubheading Linux Services
25413 @cindex out of memory killer
25415 @cindex early out of memory daemon
25416 @subsection Early OOM Service
25418 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
25419 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
25420 space and provides a more responsive and configurable alternative to the
25421 in-kernel OOM killer. It is useful to prevent the system from becoming
25422 unresponsive when it runs out of memory.
25424 @deffn {Scheme Variable} earlyoom-service-type
25425 The service type for running @command{earlyoom}, the Early OOM daemon.
25426 Its value must be a @code{earlyoom-configuration} object, described
25427 below. The service can be instantiated in its default configuration
25431 (service earlyoom-service-type)
25435 @deftp {Data Type} earlyoom-configuration
25436 This is the configuration record for the @code{earlyoom-service-type}.
25439 @item @code{earlyoom} (default: @var{earlyoom})
25440 The Earlyoom package to use.
25442 @item @code{minimum-available-memory} (default: @code{10})
25443 The threshold for the minimum @emph{available} memory, in percentages.
25445 @item @code{minimum-free-swap} (default: @code{10})
25446 The threshold for the minimum free swap memory, in percentages.
25448 @item @code{prefer-regexp} (default: @code{#f})
25449 A regular expression (as a string) to match the names of the processes
25450 that should be preferably killed.
25452 @item @code{avoid-regexp} (default: @code{#f})
25453 A regular expression (as a string) to match the names of the processes
25454 that should @emph{not} be killed.
25456 @item @code{memory-report-interval} (default: @code{0})
25457 The interval in seconds at which a memory report is printed. It is
25458 disabled by default.
25460 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
25461 A boolean indicating whether the positive adjustments set in
25462 @file{/proc/*/oom_score_adj}.
25464 @item @code{show-debug-messages?} (default: @code{#f})
25465 A boolean indicating whether debug messages should be printed. The logs
25466 are saved at @file{/var/log/earlyoom.log}.
25468 @item @code{send-notification-command} (default: @code{#f})
25469 This can be used to provide a custom command used for sending
25475 @cindex kernel module loader
25476 @subsubsection Kernel Module Loader Service
25478 The kernel module loader service allows one to load loadable kernel
25479 modules at boot. This is especially useful for modules that don't
25480 autoload and need to be manually loaded, as it's the case with
25483 @deffn {Scheme Variable} kernel-module-loader-service-type
25484 The service type for loading loadable kernel modules at boot with
25485 @command{modprobe}. Its value must be a list of strings representing
25486 module names. For example loading the drivers provided by
25487 @code{ddcci-driver-linux}, in debugging mode by passing some module
25488 parameters, can be done as follow:
25491 (use-modules (gnu) (gnu services))
25492 (use-package-modules linux)
25493 (use-service-modules linux)
25495 (define ddcci-config
25496 (plain-file "ddcci.conf"
25497 "options ddcci dyndbg delay=120"))
25501 (services (cons* (service kernel-module-loader-service-type
25502 '("ddcci" "ddcci_backlight"))
25503 (simple-service 'ddcci-config etc-service-type
25504 (list `("modprobe.d/ddcci.conf"
25507 (kernel-loadable-modules (list ddcci-driver-linux)))
25511 @node Miscellaneous Services
25512 @subsection Miscellaneous Services
25514 @cindex fingerprint
25515 @subsubheading Fingerprint Service
25517 The @code{(gnu services authentication)} module provides a DBus service to
25518 read and identify fingerprints via a fingerprint sensor.
25520 @defvr {Scheme Variable} fprintd-service-type
25521 The service type for @command{fprintd}, which provides the fingerprint
25522 reading capability.
25525 (service fprintd-service-type)
25530 @subsubheading System Control Service
25532 The @code{(gnu services sysctl)} provides a service to configure kernel
25533 parameters at boot.
25535 @defvr {Scheme Variable} sysctl-service-type
25536 The service type for @command{sysctl}, which modifies kernel parameters
25537 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
25541 (service sysctl-service-type
25542 (sysctl-configuration
25543 (settings '(("net.ipv4.ip_forward" . "1")))))
25547 @deftp {Data Type} sysctl-configuration
25548 The data type representing the configuration of @command{sysctl}.
25551 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
25552 The @command{sysctl} executable to use.
25554 @item @code{settings} (default: @code{'()})
25555 An association list specifies kernel parameters and their values.
25560 @subsubheading PC/SC Smart Card Daemon Service
25562 The @code{(gnu services security-token)} module provides the following service
25563 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
25564 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
25565 manager that coordinates communications with smart card readers, smart cards
25566 and cryptographic tokens that are connected to the system.
25568 @defvr {Scheme Variable} pcscd-service-type
25569 Service type for the @command{pcscd} service. Its value must be a
25570 @code{pcscd-configuration} object. To run pcscd in the default
25571 configuration, instantiate it as:
25574 (service pcscd-service-type)
25578 @deftp {Data Type} pcscd-configuration
25579 The data type representing the configuration of @command{pcscd}.
25582 @item @code{pcsc-lite} (default: @code{pcsc-lite})
25583 The pcsc-lite package that provides pcscd.
25584 @item @code{usb-drivers} (default: @code{(list ccid)})
25585 List of packages that provide USB drivers to pcscd. Drivers are expected to be
25586 under @file{pcsc/drivers} in the store directory of the package.
25591 @subsubheading Lirc Service
25593 The @code{(gnu services lirc)} module provides the following service.
25595 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
25596 [#:device #f] [#:driver #f] [#:config-file #f] @
25597 [#:extra-options '()]
25598 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
25599 decodes infrared signals from remote controls.
25601 Optionally, @var{device}, @var{driver} and @var{config-file}
25602 (configuration file name) may be specified. See @command{lircd} manual
25605 Finally, @var{extra-options} is a list of additional command-line options
25606 passed to @command{lircd}.
25610 @subsubheading Spice Service
25612 The @code{(gnu services spice)} module provides the following service.
25614 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
25615 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
25616 that enables sharing the clipboard with a vm and setting the guest display
25617 resolution when the graphical console window resizes.
25620 @cindex inputattach
25621 @subsubheading inputattach Service
25623 @cindex tablet input, for Xorg
25624 @cindex touchscreen input, for Xorg
25625 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
25626 use input devices such as Wacom tablets, touchscreens, or joysticks with the
25627 Xorg display server.
25629 @deffn {Scheme Variable} inputattach-service-type
25630 Type of a service that runs @command{inputattach} on a device and
25631 dispatches events from it.
25634 @deftp {Data Type} inputattach-configuration
25636 @item @code{device-type} (default: @code{"wacom"})
25637 The type of device to connect to. Run @command{inputattach --help}, from the
25638 @code{inputattach} package, to see the list of supported device types.
25640 @item @code{device} (default: @code{"/dev/ttyS0"})
25641 The device file to connect to the device.
25643 @item @code{baud-rate} (default: @code{#f})
25644 Baud rate to use for the serial connection.
25645 Should be a number or @code{#f}.
25647 @item @code{log-file} (default: @code{#f})
25648 If true, this must be the name of a file to log messages to.
25652 @subsection Dictionary Services
25654 The @code{(gnu services dict)} module provides the following service:
25656 @defvr {Scheme Variable} dicod-service-type
25657 This is the type of the service that runs the @command{dicod} daemon, an
25658 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
25661 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
25662 Return a service that runs the @command{dicod} daemon, an implementation
25663 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
25665 The optional @var{config} argument specifies the configuration for
25666 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
25667 default it serves the GNU Collaborative International Dictionary of English.
25669 You can add @command{open localhost} to your @file{~/.dico} file to make
25670 @code{localhost} the default server for @command{dico} client
25671 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
25674 @deftp {Data Type} dicod-configuration
25675 Data type representing the configuration of dicod.
25678 @item @code{dico} (default: @var{dico})
25679 Package object of the GNU Dico dictionary server.
25681 @item @code{interfaces} (default: @var{'("localhost")})
25682 This is the list of IP addresses and ports and possibly socket file
25683 names to listen to (@pxref{Server Settings, @code{listen} directive,,
25684 dico, GNU Dico Manual}).
25686 @item @code{handlers} (default: @var{'()})
25687 List of @code{<dicod-handler>} objects denoting handlers (module instances).
25689 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
25690 List of @code{<dicod-database>} objects denoting dictionaries to be served.
25694 @deftp {Data Type} dicod-handler
25695 Data type representing a dictionary handler (module instance).
25699 Name of the handler (module instance).
25701 @item @code{module} (default: @var{#f})
25702 Name of the dicod module of the handler (instance). If it is @code{#f},
25703 the module has the same name as the handler.
25704 (@pxref{Modules,,, dico, GNU Dico Manual}).
25706 @item @code{options}
25707 List of strings or gexps representing the arguments for the module handler
25711 @deftp {Data Type} dicod-database
25712 Data type representing a dictionary database.
25716 Name of the database, will be used in DICT commands.
25718 @item @code{handler}
25719 Name of the dicod handler (module instance) used by this database
25720 (@pxref{Handlers,,, dico, GNU Dico Manual}).
25722 @item @code{complex?} (default: @var{#f})
25723 Whether the database configuration complex. The complex configuration
25724 will need a corresponding @code{<dicod-handler>} object, otherwise not.
25726 @item @code{options}
25727 List of strings or gexps representing the arguments for the database
25728 (@pxref{Databases,,, dico, GNU Dico Manual}).
25732 @defvr {Scheme Variable} %dicod-database:gcide
25733 A @code{<dicod-database>} object serving the GNU Collaborative International
25734 Dictionary of English using the @code{gcide} package.
25737 The following is an example @code{dicod-service} configuration.
25740 (dicod-service #:config
25741 (dicod-configuration
25742 (handlers (list (dicod-handler
25746 (list #~(string-append "dbdir=" #$wordnet))))))
25747 (databases (list (dicod-database
25750 (handler "wordnet")
25751 (options '("database=wn")))
25752 %dicod-database:gcide))))
25756 @subsubheading Docker Service
25758 The @code{(gnu services docker)} module provides the following services.
25760 @defvr {Scheme Variable} docker-service-type
25762 This is the type of the service that runs @url{https://www.docker.com,Docker},
25763 a daemon that can execute application bundles (sometimes referred to as
25764 ``containers'') in isolated environments.
25768 @deftp {Data Type} docker-configuration
25769 This is the data type representing the configuration of Docker and Containerd.
25773 @item @code{package} (default: @code{docker})
25774 The Docker package to use.
25776 @item @code{containerd} (default: @var{containerd})
25777 The Containerd package to use.
25783 @subsubheading Auditd Service
25785 The @code{(gnu services auditd)} module provides the following service.
25787 @defvr {Scheme Variable} auditd-service-type
25789 This is the type of the service that runs
25790 @url{https://people.redhat.com/sgrubb/audit/,auditd},
25791 a daemon that tracks security-relevant information on your system.
25793 Examples of things that can be tracked:
25803 Failed login attempts
25810 @command{auditctl} from the @code{audit} package can be used in order
25811 to add or remove events to be tracked (until the next reboot).
25812 In order to permanently track events, put the command line arguments
25813 of auditctl into @file{/etc/audit/audit.rules}.
25814 @command{aureport} from the @code{audit} package can be used in order
25815 to view a report of all recorded events.
25816 The audit daemon usually logs into the directory @file{/var/log/audit}.
25820 @deftp {Data Type} auditd-configuration
25821 This is the data type representing the configuration of auditd.
25825 @item @code{audit} (default: @code{audit})
25826 The audit package to use.
25831 @defvr {Scheme Variable} singularity-service-type
25832 This is the type of the service that allows you to run
25833 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
25834 create and run application bundles (aka. ``containers''). The value for this
25835 service is the Singularity package to use.
25837 The service does not install a daemon; instead, it installs helper programs as
25838 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
25839 @command{singularity run} and similar commands.
25843 @subsubheading Nix service
25845 The @code{(gnu services nix)} module provides the following service.
25847 @defvr {Scheme Variable} nix-service-type
25849 This is the type of the service that runs build daemon of the
25850 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
25854 (use-modules (gnu))
25855 (use-service-modules nix)
25856 (use-package-modules package-management)
25860 (packages (append (list nix)
25863 (services (append (list (service nix-service-type))
25867 After @command{guix system reconfigure} configure Nix for your user:
25870 @item Add a Nix channel and update it. See
25871 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
25873 @item Create a symlink to your profile and activate Nix profile:
25877 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
25878 $ source /run/current-system/profile/etc/profile.d/nix.sh
25883 @node Setuid Programs
25884 @section Setuid Programs
25886 @cindex setuid programs
25887 Some programs need to run with ``root'' privileges, even when they are
25888 launched by unprivileged users. A notorious example is the
25889 @command{passwd} program, which users can run to change their
25890 password, and which needs to access the @file{/etc/passwd} and
25891 @file{/etc/shadow} files---something normally restricted to root, for
25892 obvious security reasons. To address that, these executables are
25893 @dfn{setuid-root}, meaning that they always run with root privileges
25894 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
25895 for more info about the setuid mechanism.)
25897 The store itself @emph{cannot} contain setuid programs: that would be a
25898 security issue since any user on the system can write derivations that
25899 populate the store (@pxref{The Store}). Thus, a different mechanism is
25900 used: instead of changing the setuid bit directly on files that are in
25901 the store, we let the system administrator @emph{declare} which programs
25902 should be setuid root.
25904 The @code{setuid-programs} field of an @code{operating-system}
25905 declaration contains a list of G-expressions denoting the names of
25906 programs to be setuid-root (@pxref{Using the Configuration System}).
25907 For instance, the @command{passwd} program, which is part of the Shadow
25908 package, can be designated by this G-expression (@pxref{G-Expressions}):
25911 #~(string-append #$shadow "/bin/passwd")
25914 A default set of setuid programs is defined by the
25915 @code{%setuid-programs} variable of the @code{(gnu system)} module.
25917 @defvr {Scheme Variable} %setuid-programs
25918 A list of G-expressions denoting common programs that are setuid-root.
25920 The list includes commands such as @command{passwd}, @command{ping},
25921 @command{su}, and @command{sudo}.
25924 Under the hood, the actual setuid programs are created in the
25925 @file{/run/setuid-programs} directory at system activation time. The
25926 files in this directory refer to the ``real'' binaries, which are in the
25929 @node X.509 Certificates
25930 @section X.509 Certificates
25932 @cindex HTTPS, certificates
25933 @cindex X.509 certificates
25935 Web servers available over HTTPS (that is, HTTP over the transport-layer
25936 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
25937 that the client can then use to @emph{authenticate} the server. To do
25938 that, clients verify that the server's certificate is signed by a
25939 so-called @dfn{certificate authority} (CA). But to verify the CA's
25940 signature, clients must have first acquired the CA's certificate.
25942 Web browsers such as GNU@tie{}IceCat include their own set of CA
25943 certificates, such that they are able to verify CA signatures
25946 However, most other programs that can talk HTTPS---@command{wget},
25947 @command{git}, @command{w3m}, etc.---need to be told where CA
25948 certificates can be found.
25950 @cindex @code{nss-certs}
25951 In Guix, this is done by adding a package that provides certificates
25952 to the @code{packages} field of the @code{operating-system} declaration
25953 (@pxref{operating-system Reference}). Guix includes one such package,
25954 @code{nss-certs}, which is a set of CA certificates provided as part of
25955 Mozilla's Network Security Services.
25957 Note that it is @emph{not} part of @code{%base-packages}, so you need to
25958 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
25959 most applications and libraries look for certificates by default, points
25960 to the certificates installed globally.
25962 Unprivileged users, including users of Guix on a foreign distro,
25963 can also install their own certificate package in
25964 their profile. A number of environment variables need to be defined so
25965 that applications and libraries know where to find them. Namely, the
25966 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
25967 variables. Some applications add their own environment variables; for
25968 instance, the Git version control system honors the certificate bundle
25969 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
25970 would typically run something like:
25973 $ guix install nss-certs
25974 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
25975 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
25976 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
25979 As another example, R requires the @code{CURL_CA_BUNDLE} environment
25980 variable to point to a certificate bundle, so you would have to run
25981 something like this:
25984 $ guix install nss-certs
25985 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
25988 For other applications you may want to look up the required environment
25989 variable in the relevant documentation.
25992 @node Name Service Switch
25993 @section Name Service Switch
25995 @cindex name service switch
25997 The @code{(gnu system nss)} module provides bindings to the
25998 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
25999 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
26000 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
26001 extended with new ``name'' lookup methods for system databases, which
26002 includes host names, service names, user accounts, and more (@pxref{Name
26003 Service Switch, System Databases and Name Service Switch,, libc, The GNU
26004 C Library Reference Manual}).
26006 The NSS configuration specifies, for each system database, which lookup
26007 method is to be used, and how the various methods are chained
26008 together---for instance, under which circumstances NSS should try the
26009 next method in the list. The NSS configuration is given in the
26010 @code{name-service-switch} field of @code{operating-system} declarations
26011 (@pxref{operating-system Reference, @code{name-service-switch}}).
26014 @cindex .local, host name lookup
26015 As an example, the declaration below configures the NSS to use the
26016 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
26017 back-end}, which supports host name lookups over multicast DNS (mDNS)
26018 for host names ending in @code{.local}:
26021 (name-service-switch
26022 (hosts (list %files ;first, check /etc/hosts
26024 ;; If the above did not succeed, try
26025 ;; with 'mdns_minimal'.
26027 (name "mdns_minimal")
26029 ;; 'mdns_minimal' is authoritative for
26030 ;; '.local'. When it returns "not found",
26031 ;; no need to try the next methods.
26032 (reaction (lookup-specification
26033 (not-found => return))))
26035 ;; Then fall back to DNS.
26039 ;; Finally, try with the "full" 'mdns'.
26044 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
26045 contains this configuration, so you will not have to type it if all you
26046 want is to have @code{.local} host lookup working.
26048 Note that, in this case, in addition to setting the
26049 @code{name-service-switch} of the @code{operating-system} declaration,
26050 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
26051 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
26052 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
26053 to the name service cache daemon (@pxref{Base Services,
26054 @code{nscd-service}}).
26056 For convenience, the following variables provide typical NSS
26059 @defvr {Scheme Variable} %default-nss
26060 This is the default name service switch configuration, a
26061 @code{name-service-switch} object.
26064 @defvr {Scheme Variable} %mdns-host-lookup-nss
26065 This is the name service switch configuration with support for host name
26066 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
26069 The reference for name service switch configuration is given below. It
26070 is a direct mapping of the configuration file format of the C library , so
26071 please refer to the C library manual for more information (@pxref{NSS
26072 Configuration File,,, libc, The GNU C Library Reference Manual}).
26073 Compared to the configuration file format of libc NSS, it has the advantage
26074 not only of adding this warm parenthetic feel that we like, but also
26075 static checks: you will know about syntax errors and typos as soon as you
26076 run @command{guix system}.
26078 @deftp {Data Type} name-service-switch
26080 This is the data type representation the configuration of libc's name
26081 service switch (NSS). Each field below represents one of the supported
26098 The system databases handled by the NSS. Each of these fields must be a
26099 list of @code{<name-service>} objects (see below).
26103 @deftp {Data Type} name-service
26105 This is the data type representing an actual name service and the
26106 associated lookup action.
26110 A string denoting the name service (@pxref{Services in the NSS
26111 configuration,,, libc, The GNU C Library Reference Manual}).
26113 Note that name services listed here must be visible to nscd. This is
26114 achieved by passing the @code{#:name-services} argument to
26115 @code{nscd-service} the list of packages providing the needed name
26116 services (@pxref{Base Services, @code{nscd-service}}).
26119 An action specified using the @code{lookup-specification} macro
26120 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
26121 Reference Manual}). For example:
26124 (lookup-specification (unavailable => continue)
26125 (success => return))
26130 @node Initial RAM Disk
26131 @section Initial RAM Disk
26134 @cindex initial RAM disk
26135 For bootstrapping purposes, the Linux-Libre kernel is passed an
26136 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
26137 root file system as well as an initialization script. The latter is
26138 responsible for mounting the real root file system, and for loading any
26139 kernel modules that may be needed to achieve that.
26141 The @code{initrd-modules} field of an @code{operating-system}
26142 declaration allows you to specify Linux-libre kernel modules that must
26143 be available in the initrd. In particular, this is where you would list
26144 modules needed to actually drive the hard disk where your root partition
26145 is---although the default value of @code{initrd-modules} should cover
26146 most use cases. For example, assuming you need the @code{megaraid_sas}
26147 module in addition to the default modules to be able to access your root
26148 file system, you would write:
26153 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
26156 @defvr {Scheme Variable} %base-initrd-modules
26157 This is the list of kernel modules included in the initrd by default.
26160 Furthermore, if you need lower-level customization, the @code{initrd}
26161 field of an @code{operating-system} declaration allows
26162 you to specify which initrd you would like to use. The @code{(gnu
26163 system linux-initrd)} module provides three ways to build an initrd: the
26164 high-level @code{base-initrd} procedure and the low-level
26165 @code{raw-initrd} and @code{expression->initrd} procedures.
26167 The @code{base-initrd} procedure is intended to cover most common uses.
26168 For example, if you want to add a bunch of kernel modules to be loaded
26169 at boot time, you can define the @code{initrd} field of the operating
26170 system declaration like this:
26173 (initrd (lambda (file-systems . rest)
26174 ;; Create a standard initrd but set up networking
26175 ;; with the parameters QEMU expects by default.
26176 (apply base-initrd file-systems
26177 #:qemu-networking? #t
26181 The @code{base-initrd} procedure also handles common use cases that
26182 involves using the system as a QEMU guest, or as a ``live'' system with
26183 volatile root file system.
26185 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
26186 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
26187 such as trying to guess which kernel modules and packages should be included
26188 to the initrd. An example use of @code{raw-initrd} is when a user has
26189 a custom Linux kernel configuration and default kernel modules included by
26190 @code{base-initrd} are not available.
26192 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
26193 honors several options passed on the Linux kernel command line
26194 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
26195 @code{-append} option of QEMU), notably:
26198 @item --load=@var{boot}
26199 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
26200 program, once it has mounted the root file system.
26202 Guix uses this option to yield control to a boot program that runs the
26203 service activation programs and then spawns the GNU@tie{}Shepherd, the
26204 initialization system.
26206 @item --root=@var{root}
26207 Mount @var{root} as the root file system. @var{root} can be a
26208 device name like @code{/dev/sda1}, a file system label, or a file system
26211 @item --system=@var{system}
26212 Have @file{/run/booted-system} and @file{/run/current-system} point to
26215 @item modprobe.blacklist=@var{modules}@dots{}
26216 @cindex module, black-listing
26217 @cindex black list, of kernel modules
26218 Instruct the initial RAM disk as well as the @command{modprobe} command
26219 (from the kmod package) to refuse to load @var{modules}. @var{modules}
26220 must be a comma-separated list of module names---e.g.,
26221 @code{usbkbd,9pnet}.
26224 Start a read-eval-print loop (REPL) from the initial RAM disk before it
26225 tries to load kernel modules and to mount the root file system. Our
26226 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
26227 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
26228 Manual}, for more information on Guile's REPL.
26232 Now that you know all the features that initial RAM disks produced by
26233 @code{base-initrd} and @code{raw-initrd} provide,
26234 here is how to use it and customize it further.
26237 @cindex initial RAM disk
26238 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
26239 [#:linux-modules '()] [#:mapped-devices '()] @
26240 [#:keyboard-layout #f] @
26241 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
26242 Return a derivation that builds a raw initrd. @var{file-systems} is
26243 a list of file systems to be mounted by the initrd, possibly in addition to
26244 the root file system specified on the kernel command line via @code{--root}.
26245 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
26246 @var{mapped-devices} is a list of device mappings to realize before
26247 @var{file-systems} are mounted (@pxref{Mapped Devices}).
26248 @var{helper-packages} is a list of packages to be copied in the initrd. It may
26249 include @code{e2fsck/static} or other packages needed by the initrd to check
26250 the root file system.
26252 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26253 the desired console keyboard layout. This is done before @var{mapped-devices}
26254 are set up and before @var{file-systems} are mounted such that, should the
26255 user need to enter a passphrase or use the REPL, this happens using the
26256 intended keyboard layout.
26258 When @var{qemu-networking?} is true, set up networking with the standard QEMU
26259 parameters. When @var{virtio?} is true, load additional modules so that the
26260 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
26262 When @var{volatile-root?} is true, the root file system is writable but any changes
26266 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
26267 [#:mapped-devices '()] [#:keyboard-layout #f] @
26268 [#:qemu-networking? #f] [#:volatile-root? #f] @
26269 [#:linux-modules '()]
26270 Return as a file-like object a generic initrd, with kernel
26271 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
26272 mounted by the initrd, possibly in addition to the root file system specified
26273 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
26274 mappings to realize before @var{file-systems} are mounted.
26276 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26277 the desired console keyboard layout. This is done before @var{mapped-devices}
26278 are set up and before @var{file-systems} are mounted such that, should the
26279 user need to enter a passphrase or use the REPL, this happens using the
26280 intended keyboard layout.
26282 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
26284 The initrd is automatically populated with all the kernel modules necessary
26285 for @var{file-systems} and for the given options. Additional kernel
26286 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
26287 loaded at boot time in the order in which they appear.
26290 Needless to say, the initrds we produce and use embed a
26291 statically-linked Guile, and the initialization program is a Guile
26292 program. That gives a lot of flexibility. The
26293 @code{expression->initrd} procedure builds such an initrd, given the
26294 program to run in that initrd.
26296 @deffn {Scheme Procedure} expression->initrd @var{exp} @
26297 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
26298 Return as a file-like object a Linux initrd (a gzipped cpio archive)
26299 containing @var{guile} and that evaluates @var{exp}, a G-expression,
26300 upon booting. All the derivations referenced by @var{exp} are
26301 automatically copied to the initrd.
26304 @node Bootloader Configuration
26305 @section Bootloader Configuration
26308 @cindex boot loader
26310 The operating system supports multiple bootloaders. The bootloader is
26311 configured using @code{bootloader-configuration} declaration. All the
26312 fields of this structure are bootloader agnostic except for one field,
26313 @code{bootloader} that indicates the bootloader to be configured and
26316 Some of the bootloaders do not honor every field of
26317 @code{bootloader-configuration}. For instance, the extlinux
26318 bootloader does not support themes and thus ignores the @code{theme}
26321 @deftp {Data Type} bootloader-configuration
26322 The type of a bootloader configuration declaration.
26326 @item @code{bootloader}
26327 @cindex EFI, bootloader
26328 @cindex UEFI, bootloader
26329 @cindex BIOS, bootloader
26330 The bootloader to use, as a @code{bootloader} object. For now
26331 @code{grub-bootloader}, @code{grub-efi-bootloader},
26332 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
26334 @vindex grub-efi-bootloader
26335 @code{grub-efi-bootloader} allows to boot on modern systems using the
26336 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
26337 use if the installation image contains a @file{/sys/firmware/efi} directory
26338 when you boot it on your system.
26340 @vindex grub-bootloader
26341 @code{grub-bootloader} allows you to boot in particular Intel-based machines
26342 in ``legacy'' BIOS mode.
26344 @cindex ARM, bootloaders
26345 @cindex AArch64, bootloaders
26346 Available bootloaders are described in @code{(gnu bootloader @dots{})}
26347 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
26348 of bootloaders for a wide range of ARM and AArch64 systems, using the
26349 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
26351 @item @code{target}
26352 This is a string denoting the target onto which to install the
26355 The interpretation depends on the bootloader in question. For
26356 @code{grub-bootloader}, for example, it should be a device name understood by
26357 the bootloader @command{installer} command, such as @code{/dev/sda} or
26358 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
26359 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
26360 system, usually @file{/boot/efi}.
26362 @item @code{menu-entries} (default: @code{()})
26363 A possibly empty list of @code{menu-entry} objects (see below), denoting
26364 entries to appear in the bootloader menu, in addition to the current
26365 system entry and the entry pointing to previous system generations.
26367 @item @code{default-entry} (default: @code{0})
26368 The index of the default boot menu entry. Index 0 is for the entry of the
26371 @item @code{timeout} (default: @code{5})
26372 The number of seconds to wait for keyboard input before booting. Set to
26373 0 to boot immediately, and to -1 to wait indefinitely.
26375 @cindex keyboard layout, for the bootloader
26376 @item @code{keyboard-layout} (default: @code{#f})
26377 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
26378 layout, usually US@tie{}English (``qwerty'').
26380 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
26384 This option is currently ignored by bootloaders other than @code{grub} and
26388 @item @code{theme} (default: @var{#f})
26389 The bootloader theme object describing the theme to use. If no theme
26390 is provided, some bootloaders might use a default theme, that's true
26393 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
26394 The output terminals used for the bootloader boot menu, as a list of
26395 symbols. GRUB accepts the values: @code{console}, @code{serial},
26396 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
26397 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
26398 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
26399 configuration,,, grub,GNU GRUB manual}).
26401 @item @code{terminal-inputs} (default: @code{'()})
26402 The input terminals used for the bootloader boot menu, as a list of
26403 symbols. For GRUB, the default is the native platform terminal as
26404 determined at run-time. GRUB accepts the values: @code{console},
26405 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
26406 @code{usb_keyboard}. This field corresponds to the GRUB variable
26407 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
26410 @item @code{serial-unit} (default: @code{#f})
26411 The serial unit used by the bootloader, as an integer from 0 to 3.
26412 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
26413 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26415 @item @code{serial-speed} (default: @code{#f})
26416 The speed of the serial interface, as an integer. For GRUB, the
26417 default value is chosen at run-time; currently GRUB chooses
26418 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26425 Should you want to list additional boot menu entries @i{via} the
26426 @code{menu-entries} field above, you will need to create them with the
26427 @code{menu-entry} form. For example, imagine you want to be able to
26428 boot another distro (hard to imagine!), you can define a menu entry
26433 (label "The Other Distro")
26434 (linux "/boot/old/vmlinux-2.6.32")
26435 (linux-arguments '("root=/dev/sda2"))
26436 (initrd "/boot/old/initrd"))
26441 @deftp {Data Type} menu-entry
26442 The type of an entry in the bootloader menu.
26447 The label to show in the menu---e.g., @code{"GNU"}.
26450 The Linux kernel image to boot, for example:
26453 (file-append linux-libre "/bzImage")
26456 For GRUB, it is also possible to specify a device explicitly in the
26457 file path using GRUB's device naming convention (@pxref{Naming
26458 convention,,, grub, GNU GRUB manual}), for example:
26461 "(hd0,msdos1)/boot/vmlinuz"
26464 If the device is specified explicitly as above, then the @code{device}
26465 field is ignored entirely.
26467 @item @code{linux-arguments} (default: @code{()})
26468 The list of extra Linux kernel command-line arguments---e.g.,
26469 @code{("console=ttyS0")}.
26471 @item @code{initrd}
26472 A G-Expression or string denoting the file name of the initial RAM disk
26473 to use (@pxref{G-Expressions}).
26474 @item @code{device} (default: @code{#f})
26475 The device where the kernel and initrd are to be found---i.e., for GRUB,
26476 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
26478 This may be a file system label (a string), a file system UUID (a
26479 bytevector, @pxref{File Systems}), or @code{#f}, in which case
26480 the bootloader will search the device containing the file specified by
26481 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
26482 must @emph{not} be an OS device name such as @file{/dev/sda1}.
26490 @c FIXME: Write documentation once it's stable.
26491 For now only GRUB has theme support. GRUB themes are created using
26492 the @code{grub-theme} form, which is not fully documented yet.
26494 @deftp {Data Type} grub-theme
26495 Data type representing the configuration of the GRUB theme.
26498 @item @code{gfxmode} (default: @code{'("auto")})
26499 The GRUB @code{gfxmode} to set (a list of screen resolution strings, see
26500 @pxref{gfxmode,,, grub, GNU GRUB manual}).
26504 @defvr {Scheme Variable} %default-theme
26505 This is the default GRUB theme used by the operating system if no
26506 @code{theme} field is specified in @code{bootloader-configuration}
26509 It comes with a fancy background image displaying the GNU and Guix
26513 For example, to override the default resolution, you may use something
26518 (grub-configuration
26521 (inherit %default-theme)
26522 (gfxmode '("1024x786x32" "auto"))))))
26525 @node Invoking guix system
26526 @section Invoking @code{guix system}
26528 Once you have written an operating system declaration as seen in the
26529 previous section, it can be @dfn{instantiated} using the @command{guix
26530 system} command. The synopsis is:
26533 guix system @var{options}@dots{} @var{action} @var{file}
26536 @var{file} must be the name of a file containing an
26537 @code{operating-system} declaration. @var{action} specifies how the
26538 operating system is instantiated. Currently the following values are
26543 Display available service type definitions that match the given regular
26544 expressions, sorted by relevance:
26550 $ guix system search console
26551 name: console-fonts
26552 location: gnu/services/base.scm:806:2
26553 extends: shepherd-root
26554 description: Install the given fonts on the specified ttys (fonts are per
26555 + virtual console on GNU/Linux). The value of this service is a list of
26556 + tty/font pairs. The font can be the name of a font provided by the `kbd'
26557 + package or any valid argument to `setfont', as in this example:
26559 + '(("tty1" . "LatGrkCyr-8x16")
26560 + ("tty2" . (file-append
26562 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
26563 + ("tty3" . (file-append
26565 + "/share/consolefonts/ter-132n"))) ; for HDPI
26569 location: gnu/services/base.scm:1190:2
26570 extends: shepherd-root
26571 description: Provide console login using the `mingetty' program.
26575 location: gnu/services/base.scm:860:2
26577 description: Provide a console log-in service as specified by its
26578 + configuration value, a `login-configuration' object.
26584 As for @command{guix package --search}, the result is written in
26585 @code{recutils} format, which makes it easy to filter the output
26586 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
26589 Build the operating system described in @var{file}, activate it, and
26590 switch to it@footnote{This action (and the related actions
26591 @code{switch-generation} and @code{roll-back}) are usable only on
26592 systems already running Guix System.}.
26595 @c The paragraph below refers to the problem discussed at
26596 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
26597 It is highly recommended to run @command{guix pull} once before you run
26598 @command{guix system reconfigure} for the first time (@pxref{Invoking
26599 guix pull}). Failing to do that you would see an older version of Guix
26600 once @command{reconfigure} has completed.
26603 This effects all the configuration specified in @var{file}: user
26604 accounts, system services, global package list, setuid programs, etc.
26605 The command starts system services specified in @var{file} that are not
26606 currently running; if a service is currently running this command will
26607 arrange for it to be upgraded the next time it is stopped (e.g.@: by
26608 @code{herd stop X} or @code{herd restart X}).
26610 This command creates a new generation whose number is one greater than
26611 the current generation (as reported by @command{guix system
26612 list-generations}). If that generation already exists, it will be
26613 overwritten. This behavior mirrors that of @command{guix package}
26614 (@pxref{Invoking guix package}).
26616 It also adds a bootloader menu entry for the new OS configuration,
26617 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
26618 entries for older configurations to a submenu, allowing you to choose
26619 an older system generation at boot time should you need it.
26621 @cindex provenance tracking, of the operating system
26622 Upon completion, the new system is deployed under
26623 @file{/run/current-system}. This directory contains @dfn{provenance
26624 meta-data}: the list of channels in use (@pxref{Channels}) and
26625 @var{file} itself, when available. This information is useful should
26626 you later want to inspect how this particular generation was built.
26628 In fact, assuming @var{file} is self-contained, you can later rebuild
26629 generation @var{n} of your operating system with:
26632 guix time-machine \
26633 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
26634 system reconfigure \
26635 /var/guix/profiles/system-@var{n}-link/configuration.scm
26638 You can think of it as some sort of built-in version control! Your
26639 system is not just a binary artifact: @emph{it carries its own source}.
26640 @xref{Service Reference, @code{provenance-service-type}}, for more
26641 information on provenance tracking.
26643 @item switch-generation
26644 @cindex generations
26645 Switch to an existing system generation. This action atomically
26646 switches the system profile to the specified system generation. It
26647 also rearranges the system's existing bootloader menu entries. It
26648 makes the menu entry for the specified system generation the default,
26649 and it moves the entries for the other generations to a submenu, if
26650 supported by the bootloader being used. The next time the system
26651 boots, it will use the specified system generation.
26653 The bootloader itself is not being reinstalled when using this
26654 command. Thus, the installed bootloader is used with an updated
26655 configuration file.
26657 The target generation can be specified explicitly by its generation
26658 number. For example, the following invocation would switch to system
26662 guix system switch-generation 7
26665 The target generation can also be specified relative to the current
26666 generation with the form @code{+N} or @code{-N}, where @code{+3} means
26667 ``3 generations ahead of the current generation,'' and @code{-1} means
26668 ``1 generation prior to the current generation.'' When specifying a
26669 negative value such as @code{-1}, you must precede it with @code{--} to
26670 prevent it from being parsed as an option. For example:
26673 guix system switch-generation -- -1
26676 Currently, the effect of invoking this action is @emph{only} to switch
26677 the system profile to an existing generation and rearrange the
26678 bootloader menu entries. To actually start using the target system
26679 generation, you must reboot after running this action. In the future,
26680 it will be updated to do the same things as @command{reconfigure},
26681 like activating and deactivating services.
26683 This action will fail if the specified generation does not exist.
26686 @cindex rolling back
26687 Switch to the preceding system generation. The next time the system
26688 boots, it will use the preceding system generation. This is the inverse
26689 of @command{reconfigure}, and it is exactly the same as invoking
26690 @command{switch-generation} with an argument of @code{-1}.
26692 Currently, as with @command{switch-generation}, you must reboot after
26693 running this action to actually start using the preceding system
26696 @item delete-generations
26697 @cindex deleting system generations
26698 @cindex saving space
26699 Delete system generations, making them candidates for garbage collection
26700 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
26703 This works in the same way as @command{guix package --delete-generations}
26704 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
26705 arguments, all system generations but the current one are deleted:
26708 guix system delete-generations
26711 You can also select the generations you want to delete. The example below
26712 deletes all the system generations that are more than two month old:
26715 guix system delete-generations 2m
26718 Running this command automatically reinstalls the bootloader with an updated
26719 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
26720 longer lists the generations that have been deleted.
26723 Build the derivation of the operating system, which includes all the
26724 configuration files and programs needed to boot and run the system.
26725 This action does not actually install anything.
26728 Populate the given directory with all the files necessary to run the
26729 operating system specified in @var{file}. This is useful for first-time
26730 installations of Guix System. For instance:
26733 guix system init my-os-config.scm /mnt
26736 copies to @file{/mnt} all the store items required by the configuration
26737 specified in @file{my-os-config.scm}. This includes configuration
26738 files, packages, and so on. It also creates other essential files
26739 needed for the system to operate correctly---e.g., the @file{/etc},
26740 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
26742 This command also installs bootloader on the target specified in
26743 @file{my-os-config}, unless the @option{--no-bootloader} option was
26747 @cindex virtual machine
26749 @anchor{guix system vm}
26750 Build a virtual machine that contains the operating system declared in
26751 @var{file}, and return a script to run that virtual machine (VM).
26754 The @code{vm} action and others below
26755 can use KVM support in the Linux-libre kernel. Specifically, if the
26756 machine has hardware virtualization support, the corresponding
26757 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
26758 must exist and be readable and writable by the user and by the
26759 build users of the daemon (@pxref{Build Environment Setup}).
26762 Arguments given to the script are passed to QEMU as in the example
26763 below, which enables networking and requests 1@tie{}GiB of RAM for the
26767 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
26770 The VM shares its store with the host system.
26772 Additional file systems can be shared between the host and the VM using
26773 the @code{--share} and @code{--expose} command-line options: the former
26774 specifies a directory to be shared with write access, while the latter
26775 provides read-only access to the shared directory.
26777 The example below creates a VM in which the user's home directory is
26778 accessible read-only, and where the @file{/exchange} directory is a
26779 read-write mapping of @file{$HOME/tmp} on the host:
26782 guix system vm my-config.scm \
26783 --expose=$HOME --share=$HOME/tmp=/exchange
26786 On GNU/Linux, the default is to boot directly to the kernel; this has
26787 the advantage of requiring only a very tiny root disk image since the
26788 store of the host can then be mounted.
26790 The @code{--full-boot} option forces a complete boot sequence, starting
26791 with the bootloader. This requires more disk space since a root image
26792 containing at least the kernel, initrd, and bootloader data files must
26793 be created. The @code{--image-size} option can be used to specify the
26796 @cindex System images, creation in various formats
26797 @cindex Creating system images in various formats
26800 @itemx docker-image
26801 Return a virtual machine, disk image, or Docker image of the operating
26802 system declared in @var{file} that stands alone. By default,
26803 @command{guix system} estimates the size of the image needed to store
26804 the system, but you can use the @option{--image-size} option to specify
26805 a value. Docker images are built to contain exactly what they need, so
26806 the @option{--image-size} option is ignored in the case of
26807 @code{docker-image}.
26809 You can specify the root file system type by using the
26810 @option{--file-system-type} option. It defaults to @code{ext4}.
26812 When using @code{vm-image}, the returned image is in qcow2 format, which
26813 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
26814 for more information on how to run the image in a virtual machine.
26816 When using @code{disk-image}, a raw disk image is produced; it can be
26817 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
26818 the device corresponding to a USB stick, one can copy the image to it
26819 using the following command:
26822 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
26825 When using @code{docker-image}, a Docker image is produced. Guix builds
26826 the image from scratch, not from a pre-existing Docker base image. As a
26827 result, it contains @emph{exactly} what you define in the operating
26828 system configuration file. You can then load the image and launch a
26829 Docker container using commands like the following:
26832 image_id="`docker load < guix-system-docker-image.tar.gz`"
26833 container_id="`docker create $image_id`"
26834 docker start $container_id
26837 This command starts a new Docker container from the specified image. It
26838 will boot the Guix system in the usual manner, which means it will
26839 start any services you have defined in the operating system
26840 configuration. You can get an interactive shell running in the container
26841 using @command{docker exec}:
26844 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
26847 Depending on what you run in the Docker container, it
26848 may be necessary to give the container additional permissions. For
26849 example, if you intend to build software using Guix inside of the Docker
26850 container, you may need to pass the @option{--privileged} option to
26851 @code{docker create}.
26854 Return a script to run the operating system declared in @var{file}
26855 within a container. Containers are a set of lightweight isolation
26856 mechanisms provided by the kernel Linux-libre. Containers are
26857 substantially less resource-demanding than full virtual machines since
26858 the kernel, shared objects, and other resources can be shared with the
26859 host system; this also means they provide thinner isolation.
26861 Currently, the script must be run as root in order to support more than
26862 a single user and group. The container shares its store with the host
26865 As with the @code{vm} action (@pxref{guix system vm}), additional file
26866 systems to be shared between the host and container can be specified
26867 using the @option{--share} and @option{--expose} options:
26870 guix system container my-config.scm \
26871 --expose=$HOME --share=$HOME/tmp=/exchange
26875 This option requires Linux-libre 3.19 or newer.
26880 @var{options} can contain any of the common build options (@pxref{Common
26881 Build Options}). In addition, @var{options} can contain one of the
26885 @item --expression=@var{expr}
26886 @itemx -e @var{expr}
26887 Consider the operating-system @var{expr} evaluates to.
26888 This is an alternative to specifying a file which evaluates to an
26890 This is used to generate the Guix system installer @pxref{Building the
26891 Installation Image}).
26893 @item --system=@var{system}
26894 @itemx -s @var{system}
26895 Attempt to build for @var{system} instead of the host system type.
26896 This works as per @command{guix build} (@pxref{Invoking guix build}).
26900 Return the derivation file name of the given operating system without
26903 @cindex provenance tracking, of the operating system
26904 @item --save-provenance
26905 As discussed above, @command{guix system init} and @command{guix system
26906 reconfigure} always save provenance information @i{via} a dedicated
26907 service (@pxref{Service Reference, @code{provenance-service-type}}).
26908 However, other commands don't do that by default. If you wish to, say,
26909 create a virtual machine image that contains provenance information, you
26913 guix system vm-image --save-provenance config.scm
26916 That way, the resulting image will effectively ``embed its own source''
26917 in the form of meta-data in @file{/run/current-system}. With that
26918 information, one can rebuild the image to make sure it really contains
26919 what it pretends to contain; or they could use that to derive a variant
26922 @item --file-system-type=@var{type}
26923 @itemx -t @var{type}
26924 For the @code{disk-image} action, create a file system of the given
26925 @var{type} on the image.
26927 When this option is omitted, @command{guix system} uses @code{ext4}.
26929 @cindex ISO-9660 format
26930 @cindex CD image format
26931 @cindex DVD image format
26932 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
26933 for burning on CDs and DVDs.
26935 @item --image-size=@var{size}
26936 For the @code{vm-image} and @code{disk-image} actions, create an image
26937 of the given @var{size}. @var{size} may be a number of bytes, or it may
26938 include a unit as a suffix (@pxref{Block size, size specifications,,
26939 coreutils, GNU Coreutils}).
26941 When this option is omitted, @command{guix system} computes an estimate
26942 of the image size as a function of the size of the system declared in
26947 For the @code{container} action, allow containers to access the host network,
26948 that is, do not create a network namespace.
26950 @item --root=@var{file}
26951 @itemx -r @var{file}
26952 Make @var{file} a symlink to the result, and register it as a garbage
26955 @item --skip-checks
26956 Skip pre-installation safety checks.
26958 By default, @command{guix system init} and @command{guix system
26959 reconfigure} perform safety checks: they make sure the file systems that
26960 appear in the @code{operating-system} declaration actually exist
26961 (@pxref{File Systems}), and that any Linux kernel modules that may be
26962 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
26963 RAM Disk}). Passing this option skips these tests altogether.
26966 @cindex on-error strategy
26967 @cindex error strategy
26968 @item --on-error=@var{strategy}
26969 Apply @var{strategy} when an error occurs when reading @var{file}.
26970 @var{strategy} may be one of the following:
26973 @item nothing-special
26974 Report the error concisely and exit. This is the default strategy.
26977 Likewise, but also display a backtrace.
26980 Report the error and enter Guile's debugger. From there, you can run
26981 commands such as @code{,bt} to get a backtrace, @code{,locals} to
26982 display local variable values, and more generally inspect the state of the
26983 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
26984 a list of available debugging commands.
26988 Once you have built, configured, re-configured, and re-re-configured
26989 your Guix installation, you may find it useful to list the operating
26990 system generations available on disk---and that you can choose from the
26991 bootloader boot menu:
26996 Describe the current system generation: its file name, the kernel and
26997 bootloader used, etc., as well as provenance information when available.
26999 @item list-generations
27000 List a summary of each generation of the operating system available on
27001 disk, in a human-readable way. This is similar to the
27002 @option{--list-generations} option of @command{guix package}
27003 (@pxref{Invoking guix package}).
27005 Optionally, one can specify a pattern, with the same syntax that is used
27006 in @command{guix package --list-generations}, to restrict the list of
27007 generations displayed. For instance, the following command displays
27008 generations that are up to 10 days old:
27011 $ guix system list-generations 10d
27016 The @command{guix system} command has even more to offer! The following
27017 sub-commands allow you to visualize how your system services relate to
27020 @anchor{system-extension-graph}
27023 @item extension-graph
27024 Emit in Dot/Graphviz format to standard output the @dfn{service
27025 extension graph} of the operating system defined in @var{file}
27026 (@pxref{Service Composition}, for more information on service
27032 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
27035 produces a PDF file showing the extension relations among services.
27037 @anchor{system-shepherd-graph}
27038 @item shepherd-graph
27039 Emit in Dot/Graphviz format to standard output the @dfn{dependency
27040 graph} of shepherd services of the operating system defined in
27041 @var{file}. @xref{Shepherd Services}, for more information and for an
27046 @node Invoking guix deploy
27047 @section Invoking @code{guix deploy}
27049 We've already seen @code{operating-system} declarations used to manage a
27050 machine's configuration locally. Suppose you need to configure multiple
27051 machines, though---perhaps you're managing a service on the web that's
27052 comprised of several servers. @command{guix deploy} enables you to use those
27053 same @code{operating-system} declarations to manage multiple remote hosts at
27054 once as a logical ``deployment''.
27057 The functionality described in this section is still under development
27058 and is subject to change. Get in touch with us on
27059 @email{guix-devel@@gnu.org}!
27063 guix deploy @var{file}
27066 Such an invocation will deploy the machines that the code within @var{file}
27067 evaluates to. As an example, @var{file} might contain a definition like this:
27070 ;; This is a Guix deployment of a "bare bones" setup, with
27071 ;; no X11 display server, to a machine with an SSH daemon
27072 ;; listening on localhost:2222. A configuration such as this
27073 ;; may be appropriate for virtual machine with ports
27074 ;; forwarded to the host's loopback interface.
27076 (use-service-modules networking ssh)
27077 (use-package-modules bootloaders)
27081 (host-name "gnu-deployed")
27082 (timezone "Etc/UTC")
27083 (bootloader (bootloader-configuration
27084 (bootloader grub-bootloader)
27085 (target "/dev/vda")
27086 (terminal-outputs '(console))))
27087 (file-systems (cons (file-system
27089 (device "/dev/vda1")
27091 %base-file-systems))
27093 (append (list (service dhcp-client-service-type)
27094 (service openssh-service-type
27095 (openssh-configuration
27096 (permit-root-login #t)
27097 (allow-empty-passwords? #t))))
27101 (operating-system %system)
27102 (environment managed-host-environment-type)
27103 (configuration (machine-ssh-configuration
27104 (host-name "localhost")
27105 (system "x86_64-linux")
27107 (identity "./id_rsa")
27111 The file should evaluate to a list of @var{machine} objects. This example,
27112 upon being deployed, will create a new generation on the remote system
27113 realizing the @code{operating-system} declaration @code{%system}.
27114 @code{environment} and @code{configuration} specify how the machine should be
27115 provisioned---that is, how the computing resources should be created and
27116 managed. The above example does not create any resources, as a
27117 @code{'managed-host} is a machine that is already running the Guix system and
27118 available over the network. This is a particularly simple case; a more
27119 complex deployment may involve, for example, starting virtual machines through
27120 a Virtual Private Server (VPS) provider. In such a case, a different
27121 @var{environment} type would be used.
27123 Do note that you first need to generate a key pair on the coordinator machine
27124 to allow the daemon to export signed archives of files from the store
27125 (@pxref{Invoking guix archive}).
27128 # guix archive --generate-key
27132 Each target machine must authorize the key of the master machine so that it
27133 accepts store items it receives from the coordinator:
27136 # guix archive --authorize < coordinator-public-key.txt
27139 @code{user}, in this example, specifies the name of the user account to log in
27140 as to perform the deployment. Its default value is @code{root}, but root
27141 login over SSH may be forbidden in some cases. To work around this,
27142 @command{guix deploy} can log in as an unprivileged user and employ
27143 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
27144 currently installed on the remote and can be invoked non-interactively as
27145 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
27146 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
27147 be accomplished with the following operating system configuration snippet:
27151 (gnu system)) ;for %sudoers-specification
27153 (define %user "username")
27158 (plain-file "sudoers"
27159 (string-append (plain-file-content %sudoers-specification)
27160 (format #f "~a ALL = NOPASSWD: ALL~%"
27165 For more information regarding the format of the @file{sudoers} file,
27166 consult @command{man sudoers}.
27168 @deftp {Data Type} machine
27169 This is the data type representing a single machine in a heterogeneous Guix
27173 @item @code{operating-system}
27174 The object of the operating system configuration to deploy.
27176 @item @code{environment}
27177 An @code{environment-type} describing how the machine should be provisioned.
27179 @item @code{configuration} (default: @code{#f})
27180 An object describing the configuration for the machine's @code{environment}.
27181 If the @code{environment} has a default configuration, @code{#f} may be used.
27182 If @code{#f} is used for an environment with no default configuration,
27183 however, an error will be thrown.
27187 @deftp {Data Type} machine-ssh-configuration
27188 This is the data type representing the SSH client parameters for a machine
27189 with an @code{environment} of @code{managed-host-environment-type}.
27192 @item @code{host-name}
27193 @item @code{build-locally?} (default: @code{#t})
27194 If false, system derivations will be built on the machine being deployed to.
27195 @item @code{system}
27196 The system type describing the architecture of the machine being deployed
27197 to---e.g., @code{"x86_64-linux"}.
27198 @item @code{authorize?} (default: @code{#t})
27199 If true, the coordinator's signing key will be added to the remote's ACL
27201 @item @code{port} (default: @code{22})
27202 @item @code{user} (default: @code{"root"})
27203 @item @code{identity} (default: @code{#f})
27204 If specified, the path to the SSH private key to use to authenticate with the
27207 @item @code{host-key} (default: @code{#f})
27208 This should be the SSH host key of the machine, which looks like this:
27211 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
27214 When @code{host-key} is @code{#f}, the server is authenticated against
27215 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
27221 @deftp {Data Type} digital-ocean-configuration
27222 This is the data type describing the Droplet that should be created for a
27223 machine with an @code{environment} of @code{digital-ocean-environment-type}.
27226 @item @code{ssh-key}
27227 The path to the SSH private key to use to authenticate with the remote
27228 host. In the future, this field may not exist.
27230 A list of string ``tags'' that uniquely identify the machine. Must be given
27231 such that no two machines in the deployment have the same set of tags.
27232 @item @code{region}
27233 A Digital Ocean region slug, such as @code{"nyc3"}.
27235 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
27236 @item @code{enable-ipv6?}
27237 Whether or not the droplet should be created with IPv6 networking.
27241 @node Running Guix in a VM
27242 @section Running Guix in a Virtual Machine
27244 @cindex virtual machine
27245 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
27247 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
27248 This image is a compressed image in QCOW format. You will first need to
27249 decompress with @command{xz -d}, and then you can pass it to an emulator such
27250 as QEMU (see below for details).
27252 This image boots the Xfce graphical environment and it contains some
27253 commonly-used tools. You can install more software in the image by running
27254 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
27255 also reconfigure the system based on its initial configuration file available
27256 as @file{/run/current-system/configuration.scm} (@pxref{Using the
27257 Configuration System}).
27259 Instead of using this pre-built image, one can also build their own virtual
27260 machine image using @command{guix system vm-image} (@pxref{Invoking guix
27261 system}). The returned image is in qcow2 format, which the
27262 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
27265 If you built your own image, you must copy it out of the store
27266 (@pxref{The Store}) and give yourself permission to write to the copy
27267 before you can use it. When invoking QEMU, you must choose a system
27268 emulator that is suitable for your hardware platform. Here is a minimal
27269 QEMU invocation that will boot the result of @command{guix system
27270 vm-image} on x86_64 hardware:
27273 $ qemu-system-x86_64 \
27274 -nic user,model=virtio-net-pci \
27275 -enable-kvm -m 1024 \
27276 -device virtio-blk,drive=myhd \
27277 -drive if=none,file=/tmp/qemu-image,id=myhd
27280 Here is what each of these options means:
27283 @item qemu-system-x86_64
27284 This specifies the hardware platform to emulate. This should match the
27287 @item -nic user,model=virtio-net-pci
27288 Enable the unprivileged user-mode network stack. The guest OS can
27289 access the host but not vice versa. This is the simplest way to get the
27290 guest OS online. @code{model} specifies which network device to emulate:
27291 @code{virtio-net-pci} is a special device made for virtualized operating
27292 systems and recommended for most uses. Assuming your hardware platform is
27293 x86_64, you can get a list of available NIC models by running
27294 @command{qemu-system-x86_64 -nic model=help}.
27297 If your system has hardware virtualization extensions, enabling the
27298 virtual machine support (KVM) of the Linux kernel will make things run
27301 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
27303 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
27304 which may be insufficient for some operations.
27306 @item -device virtio-blk,drive=myhd
27307 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
27308 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
27309 better performance than if it were emulating a complete disk drive. See the
27310 QEMU and KVM documentation for more info.
27312 @item -drive if=none,file=/tmp/qemu-image,id=myhd
27313 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
27314 the ``myhd'' drive.
27317 The default @command{run-vm.sh} script that is returned by an invocation of
27318 @command{guix system vm} does not add a @command{-nic user} flag by default.
27319 To get network access from within the vm add the @code{(dhcp-client-service)}
27320 to your system definition and start the VM using
27321 @command{`guix system vm config.scm` -nic user}. An important caveat of using
27322 @command{-nic user} for networking is that @command{ping} will not work, because
27323 it uses the ICMP protocol. You'll have to use a different command to check for
27324 network connectivity, for example @command{guix download}.
27326 @subsection Connecting Through SSH
27330 To enable SSH inside a VM you need to add an SSH server like
27331 @code{openssh-service-type} to your VM (@pxref{Networking Services,
27332 @code{openssh-service-type}}). In addition you need to forward the SSH port,
27333 22 by default, to the host. You can do this with
27336 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
27339 To connect to the VM you can run
27342 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
27345 The @command{-p} tells @command{ssh} the port you want to connect to.
27346 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
27347 every time you modify your @command{config.scm} file and the
27348 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
27349 connection to an unknown host every time you connect.
27351 @subsection Using @command{virt-viewer} with Spice
27353 As an alternative to the default @command{qemu} graphical client you can
27354 use the @command{remote-viewer} from the @command{virt-viewer} package. To
27355 connect pass the @command{-spice port=5930,disable-ticketing} flag to
27356 @command{qemu}. See previous section for further information on how to do this.
27358 Spice also allows you to do some nice stuff like share your clipboard with your
27359 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
27362 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
27363 -chardev spicevmc,name=vdagent,id=vdagent
27364 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
27365 name=com.redhat.spice.0
27368 You'll also need to add the @code{(spice-vdagent-service)} to your
27369 system definition (@pxref{Miscellaneous Services, Spice service}).
27371 @node Defining Services
27372 @section Defining Services
27374 The previous sections show the available services and how one can combine
27375 them in an @code{operating-system} declaration. But how do we define
27376 them in the first place? And what is a service anyway?
27379 * Service Composition:: The model for composing services.
27380 * Service Types and Services:: Types and services.
27381 * Service Reference:: API reference.
27382 * Shepherd Services:: A particular type of service.
27385 @node Service Composition
27386 @subsection Service Composition
27390 Here we define a @dfn{service} as, broadly, something that extends the
27391 functionality of the operating system. Often a service is a process---a
27392 @dfn{daemon}---started when the system boots: a secure shell server, a
27393 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
27394 whose execution can be triggered by another daemon---e.g., an FTP server
27395 started by @command{inetd} or a D-Bus service activated by
27396 @command{dbus-daemon}. Occasionally, a service does not map to a
27397 daemon. For instance, the ``account'' service collects user accounts
27398 and makes sure they exist when the system runs; the ``udev'' service
27399 collects device management rules and makes them available to the eudev
27400 daemon; the @file{/etc} service populates the @file{/etc} directory
27403 @cindex service extensions
27404 Guix system services are connected by @dfn{extensions}. For instance, the
27405 secure shell service @emph{extends} the Shepherd---the
27406 initialization system, running as PID@tie{}1---by giving it the command
27407 lines to start and stop the secure shell daemon (@pxref{Networking
27408 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
27409 service by passing it its @file{.service} specification, and extends the
27410 udev service by passing it device management rules (@pxref{Desktop
27411 Services, @code{upower-service}}); the Guix daemon service extends the
27412 Shepherd by passing it the command lines to start and stop the daemon,
27413 and extends the account service by passing it a list of required build
27414 user accounts (@pxref{Base Services}).
27416 All in all, services and their ``extends'' relations form a directed
27417 acyclic graph (DAG). If we represent services as boxes and extensions
27418 as arrows, a typical system might provide something like this:
27420 @image{images/service-graph,,5in,Typical service extension graph.}
27422 @cindex system service
27423 At the bottom, we see the @dfn{system service}, which produces the
27424 directory containing everything to run and boot the system, as returned
27425 by the @command{guix system build} command. @xref{Service Reference},
27426 to learn about the other service types shown here.
27427 @xref{system-extension-graph, the @command{guix system extension-graph}
27428 command}, for information on how to generate this representation for a
27429 particular operating system definition.
27431 @cindex service types
27432 Technically, developers can define @dfn{service types} to express these
27433 relations. There can be any number of services of a given type on the
27434 system---for instance, a system running two instances of the GNU secure
27435 shell server (lsh) has two instances of @code{lsh-service-type}, with
27436 different parameters.
27438 The following section describes the programming interface for service
27439 types and services.
27441 @node Service Types and Services
27442 @subsection Service Types and Services
27444 A @dfn{service type} is a node in the DAG described above. Let us start
27445 with a simple example, the service type for the Guix build daemon
27446 (@pxref{Invoking guix-daemon}):
27449 (define guix-service-type
27453 (list (service-extension shepherd-root-service-type guix-shepherd-service)
27454 (service-extension account-service-type guix-accounts)
27455 (service-extension activation-service-type guix-activation)))
27456 (default-value (guix-configuration))))
27460 It defines three things:
27464 A name, whose sole purpose is to make inspection and debugging easier.
27467 A list of @dfn{service extensions}, where each extension designates the
27468 target service type and a procedure that, given the parameters of the
27469 service, returns a list of objects to extend the service of that type.
27471 Every service type has at least one service extension. The only
27472 exception is the @dfn{boot service type}, which is the ultimate service.
27475 Optionally, a default value for instances of this type.
27478 In this example, @code{guix-service-type} extends three services:
27481 @item shepherd-root-service-type
27482 The @code{guix-shepherd-service} procedure defines how the Shepherd
27483 service is extended. Namely, it returns a @code{<shepherd-service>}
27484 object that defines how @command{guix-daemon} is started and stopped
27485 (@pxref{Shepherd Services}).
27487 @item account-service-type
27488 This extension for this service is computed by @code{guix-accounts},
27489 which returns a list of @code{user-group} and @code{user-account}
27490 objects representing the build user accounts (@pxref{Invoking
27493 @item activation-service-type
27494 Here @code{guix-activation} is a procedure that returns a gexp, which is
27495 a code snippet to run at ``activation time''---e.g., when the service is
27499 A service of this type is instantiated like this:
27502 (service guix-service-type
27503 (guix-configuration
27505 (use-substitutes? #f)))
27508 The second argument to the @code{service} form is a value representing
27509 the parameters of this specific service instance.
27510 @xref{guix-configuration-type, @code{guix-configuration}}, for
27511 information about the @code{guix-configuration} data type. When the
27512 value is omitted, the default value specified by
27513 @code{guix-service-type} is used:
27516 (service guix-service-type)
27519 @code{guix-service-type} is quite simple because it extends other
27520 services but is not extensible itself.
27522 @c @subsubsubsection Extensible Service Types
27524 The service type for an @emph{extensible} service looks like this:
27527 (define udev-service-type
27528 (service-type (name 'udev)
27530 (list (service-extension shepherd-root-service-type
27531 udev-shepherd-service)))
27533 (compose concatenate) ;concatenate the list of rules
27534 (extend (lambda (config rules)
27536 (($ <udev-configuration> udev initial-rules)
27537 (udev-configuration
27538 (udev udev) ;the udev package to use
27539 (rules (append initial-rules rules)))))))))
27542 This is the service type for the
27543 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
27544 management daemon}. Compared to the previous example, in addition to an
27545 extension of @code{shepherd-root-service-type}, we see two new fields:
27549 This is the procedure to @dfn{compose} the list of extensions to
27550 services of this type.
27552 Services can extend the udev service by passing it lists of rules; we
27553 compose those extensions simply by concatenating them.
27556 This procedure defines how the value of the service is @dfn{extended} with
27557 the composition of the extensions.
27559 Udev extensions are composed into a list of rules, but the udev service
27560 value is itself a @code{<udev-configuration>} record. So here, we
27561 extend that record by appending the list of rules it contains to the
27562 list of contributed rules.
27565 This is a string giving an overview of the service type. The string can
27566 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
27567 @command{guix system search} command searches these strings and displays
27568 them (@pxref{Invoking guix system}).
27571 There can be only one instance of an extensible service type such as
27572 @code{udev-service-type}. If there were more, the
27573 @code{service-extension} specifications would be ambiguous.
27575 Still here? The next section provides a reference of the programming
27576 interface for services.
27578 @node Service Reference
27579 @subsection Service Reference
27581 We have seen an overview of service types (@pxref{Service Types and
27582 Services}). This section provides a reference on how to manipulate
27583 services and service types. This interface is provided by the
27584 @code{(gnu services)} module.
27586 @deffn {Scheme Procedure} service @var{type} [@var{value}]
27587 Return a new service of @var{type}, a @code{<service-type>} object (see
27588 below.) @var{value} can be any object; it represents the parameters of
27589 this particular service instance.
27591 When @var{value} is omitted, the default value specified by @var{type}
27592 is used; if @var{type} does not specify a default value, an error is
27595 For instance, this:
27598 (service openssh-service-type)
27602 is equivalent to this:
27605 (service openssh-service-type
27606 (openssh-configuration))
27609 In both cases the result is an instance of @code{openssh-service-type}
27610 with the default configuration.
27613 @deffn {Scheme Procedure} service? @var{obj}
27614 Return true if @var{obj} is a service.
27617 @deffn {Scheme Procedure} service-kind @var{service}
27618 Return the type of @var{service}---i.e., a @code{<service-type>} object.
27621 @deffn {Scheme Procedure} service-value @var{service}
27622 Return the value associated with @var{service}. It represents its
27626 Here is an example of how a service is created and manipulated:
27630 (service nginx-service-type
27631 (nginx-configuration
27633 (log-directory log-directory)
27634 (run-directory run-directory)
27635 (file config-file))))
27640 (eq? (service-kind s) nginx-service-type)
27644 The @code{modify-services} form provides a handy way to change the
27645 parameters of some of the services of a list such as
27646 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
27647 evaluates to a list of services. Of course, you could always use
27648 standard list combinators such as @code{map} and @code{fold} to do that
27649 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
27650 @code{modify-services} simply provides a more concise form for this
27653 @deffn {Scheme Syntax} modify-services @var{services} @
27654 (@var{type} @var{variable} => @var{body}) @dots{}
27656 Modify the services listed in @var{services} according to the given
27657 clauses. Each clause has the form:
27660 (@var{type} @var{variable} => @var{body})
27663 where @var{type} is a service type---e.g.,
27664 @code{guix-service-type}---and @var{variable} is an identifier that is
27665 bound within the @var{body} to the service parameters---e.g., a
27666 @code{guix-configuration} instance---of the original service of that
27669 The @var{body} should evaluate to the new service parameters, which will
27670 be used to configure the new service. This new service will replace the
27671 original in the resulting list. Because a service's service parameters
27672 are created using @code{define-record-type*}, you can write a succinct
27673 @var{body} that evaluates to the new service parameters by using the
27674 @code{inherit} feature that @code{define-record-type*} provides.
27676 @xref{Using the Configuration System}, for example usage.
27680 Next comes the programming interface for service types. This is
27681 something you want to know when writing new service definitions, but not
27682 necessarily when simply looking for ways to customize your
27683 @code{operating-system} declaration.
27685 @deftp {Data Type} service-type
27686 @cindex service type
27687 This is the representation of a @dfn{service type} (@pxref{Service Types
27692 This is a symbol, used only to simplify inspection and debugging.
27694 @item @code{extensions}
27695 A non-empty list of @code{<service-extension>} objects (see below).
27697 @item @code{compose} (default: @code{#f})
27698 If this is @code{#f}, then the service type denotes services that cannot
27699 be extended---i.e., services that do not receive ``values'' from other
27702 Otherwise, it must be a one-argument procedure. The procedure is called
27703 by @code{fold-services} and is passed a list of values collected from
27704 extensions. It may return any single value.
27706 @item @code{extend} (default: @code{#f})
27707 If this is @code{#f}, services of this type cannot be extended.
27709 Otherwise, it must be a two-argument procedure: @code{fold-services}
27710 calls it, passing it the initial value of the service as the first
27711 argument and the result of applying @code{compose} to the extension
27712 values as the second argument. It must return a value that is a valid
27713 parameter value for the service instance.
27716 @xref{Service Types and Services}, for examples.
27719 @deffn {Scheme Procedure} service-extension @var{target-type} @
27721 Return a new extension for services of type @var{target-type}.
27722 @var{compute} must be a one-argument procedure: @code{fold-services}
27723 calls it, passing it the value associated with the service that provides
27724 the extension; it must return a valid value for the target service.
27727 @deffn {Scheme Procedure} service-extension? @var{obj}
27728 Return true if @var{obj} is a service extension.
27731 Occasionally, you might want to simply extend an existing service. This
27732 involves creating a new service type and specifying the extension of
27733 interest, which can be verbose; the @code{simple-service} procedure
27734 provides a shorthand for this.
27736 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
27737 Return a service that extends @var{target} with @var{value}. This works
27738 by creating a singleton service type @var{name}, of which the returned
27739 service is an instance.
27741 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
27745 (simple-service 'my-mcron-job mcron-service-type
27746 #~(job '(next-hour (3)) "guix gc -F 2G"))
27750 At the core of the service abstraction lies the @code{fold-services}
27751 procedure, which is responsible for ``compiling'' a list of services
27752 down to a single directory that contains everything needed to boot and
27753 run the system---the directory shown by the @command{guix system build}
27754 command (@pxref{Invoking guix system}). In essence, it propagates
27755 service extensions down the service graph, updating each node parameters
27756 on the way, until it reaches the root node.
27758 @deffn {Scheme Procedure} fold-services @var{services} @
27759 [#:target-type @var{system-service-type}]
27760 Fold @var{services} by propagating their extensions down to the root of
27761 type @var{target-type}; return the root service adjusted accordingly.
27764 Lastly, the @code{(gnu services)} module also defines several essential
27765 service types, some of which are listed below.
27767 @defvr {Scheme Variable} system-service-type
27768 This is the root of the service graph. It produces the system directory
27769 as returned by the @command{guix system build} command.
27772 @defvr {Scheme Variable} boot-service-type
27773 The type of the ``boot service'', which produces the @dfn{boot script}.
27774 The boot script is what the initial RAM disk runs when booting.
27777 @defvr {Scheme Variable} etc-service-type
27778 The type of the @file{/etc} service. This service is used to create
27779 files under @file{/etc} and can be extended by
27780 passing it name/file tuples such as:
27783 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
27786 In this example, the effect would be to add an @file{/etc/issue} file
27787 pointing to the given file.
27790 @defvr {Scheme Variable} setuid-program-service-type
27791 Type for the ``setuid-program service''. This service collects lists of
27792 executable file names, passed as gexps, and adds them to the set of
27793 setuid-root programs on the system (@pxref{Setuid Programs}).
27796 @defvr {Scheme Variable} profile-service-type
27797 Type of the service that populates the @dfn{system profile}---i.e., the
27798 programs under @file{/run/current-system/profile}. Other services can
27799 extend it by passing it lists of packages to add to the system profile.
27802 @cindex provenance tracking, of the operating system
27803 @defvr {Scheme Variable} provenance-service-type
27804 This is the type of the service that records @dfn{provenance meta-data}
27805 in the system itself. It creates several files under
27806 @file{/run/current-system}:
27810 This is a ``channel file'' that can be passed to @command{guix pull -C}
27811 or @command{guix time-machine -C}, and which describes the channels used
27812 to build the system, if that information was available
27813 (@pxref{Channels}).
27815 @item configuration.scm
27816 This is the file that was passed as the value for this
27817 @code{provenance-service-type} service. By default, @command{guix
27818 system reconfigure} automatically passes the OS configuration file it
27819 received on the command line.
27822 This contains the same information as the two other files but in a
27823 format that is more readily processable.
27826 In general, these two pieces of information (channels and configuration
27827 file) are enough to reproduce the operating system ``from source''.
27830 This information is necessary to rebuild your operating system, but it
27831 is not always sufficient. In particular, @file{configuration.scm}
27832 itself is insufficient if it is not self-contained---if it refers to
27833 external Guile modules or to extra files. If you want
27834 @file{configuration.scm} to be self-contained, we recommend that modules
27835 or files it refers to be part of a channel.
27837 Besides, provenance meta-data is ``silent'' in the sense that it does
27838 not change the bits contained in your system, @emph{except for the
27839 meta-data bits themselves}. Two different OS configurations or sets of
27840 channels can lead to the same system, bit-for-bit; when
27841 @code{provenance-service-type} is used, these two systems will have
27842 different meta-data and thus different store file names, which makes
27843 comparison less trivial.
27846 This service is automatically added to your operating system
27847 configuration when you use @command{guix system reconfigure},
27848 @command{guix system init}, or @command{guix deploy}.
27851 @node Shepherd Services
27852 @subsection Shepherd Services
27854 @cindex shepherd services
27856 @cindex init system
27857 The @code{(gnu services shepherd)} module provides a way to define
27858 services managed by the GNU@tie{}Shepherd, which is the
27859 initialization system---the first process that is started when the
27860 system boots, also known as PID@tie{}1
27861 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
27863 Services in the Shepherd can depend on each other. For instance, the
27864 SSH daemon may need to be started after the syslog daemon has been
27865 started, which in turn can only happen once all the file systems have
27866 been mounted. The simple operating system defined earlier (@pxref{Using
27867 the Configuration System}) results in a service graph like this:
27869 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
27871 You can actually generate such a graph for any operating system
27872 definition using the @command{guix system shepherd-graph} command
27873 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
27875 The @code{%shepherd-root-service} is a service object representing
27876 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
27877 by passing it lists of @code{<shepherd-service>} objects.
27879 @deftp {Data Type} shepherd-service
27880 The data type representing a service managed by the Shepherd.
27883 @item @code{provision}
27884 This is a list of symbols denoting what the service provides.
27886 These are the names that may be passed to @command{herd start},
27887 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
27888 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
27889 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
27891 @item @code{requirement} (default: @code{'()})
27892 List of symbols denoting the Shepherd services this one depends on.
27894 @cindex one-shot services, for the Shepherd
27895 @item @code{one-shot?} (default: @code{#f})
27896 Whether this service is @dfn{one-shot}. One-shot services stop immediately
27897 after their @code{start} action has completed. @xref{Slots of services,,,
27898 shepherd, The GNU Shepherd Manual}, for more info.
27900 @item @code{respawn?} (default: @code{#t})
27901 Whether to restart the service when it stops, for instance when the
27902 underlying process dies.
27905 @itemx @code{stop} (default: @code{#~(const #f)})
27906 The @code{start} and @code{stop} fields refer to the Shepherd's
27907 facilities to start and stop processes (@pxref{Service De- and
27908 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
27909 G-expressions that get expanded in the Shepherd configuration file
27910 (@pxref{G-Expressions}).
27912 @item @code{actions} (default: @code{'()})
27913 @cindex actions, of Shepherd services
27914 This is a list of @code{shepherd-action} objects (see below) defining
27915 @dfn{actions} supported by the service, in addition to the standard
27916 @code{start} and @code{stop} actions. Actions listed here become available as
27917 @command{herd} sub-commands:
27920 herd @var{action} @var{service} [@var{arguments}@dots{}]
27923 @item @code{auto-start?} (default: @code{#t})
27924 Whether this service should be started automatically by the Shepherd. If it
27925 is @code{#f} the service has to be started manually with @code{herd start}.
27927 @item @code{documentation}
27928 A documentation string, as shown when running:
27931 herd doc @var{service-name}
27934 where @var{service-name} is one of the symbols in @code{provision}
27935 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
27937 @item @code{modules} (default: @code{%default-modules})
27938 This is the list of modules that must be in scope when @code{start} and
27939 @code{stop} are evaluated.
27944 @deftp {Data Type} shepherd-action
27945 This is the data type that defines additional actions implemented by a
27946 Shepherd service (see above).
27950 Symbol naming the action.
27952 @item documentation
27953 This is a documentation string for the action. It can be viewed by running:
27956 herd doc @var{service} action @var{action}
27960 This should be a gexp that evaluates to a procedure of at least one argument,
27961 which is the ``running value'' of the service (@pxref{Slots of services,,,
27962 shepherd, The GNU Shepherd Manual}).
27965 The following example defines an action called @code{say-hello} that kindly
27971 (documentation "Say hi!")
27972 (procedure #~(lambda (running . args)
27973 (format #t "Hello, friend! arguments: ~s\n"
27978 Assuming this action is added to the @code{example} service, then you can do:
27981 # herd say-hello example
27982 Hello, friend! arguments: ()
27983 # herd say-hello example a b c
27984 Hello, friend! arguments: ("a" "b" "c")
27987 This, as you can see, is a fairly sophisticated way to say hello.
27988 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
27992 @defvr {Scheme Variable} shepherd-root-service-type
27993 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
27995 This is the service type that extensions target when they want to create
27996 shepherd services (@pxref{Service Types and Services}, for an example).
27997 Each extension must pass a list of @code{<shepherd-service>}.
28000 @defvr {Scheme Variable} %shepherd-root-service
28001 This service represents PID@tie{}1.
28005 @node Documentation
28006 @chapter Documentation
28008 @cindex documentation, searching for
28009 @cindex searching for documentation
28010 @cindex Info, documentation format
28012 @cindex manual pages
28013 In most cases packages installed with Guix come with documentation.
28014 There are two main documentation formats: ``Info'', a browseable
28015 hypertext format used for GNU software, and ``manual pages'' (or ``man
28016 pages''), the linear documentation format traditionally found on Unix.
28017 Info manuals are accessed with the @command{info} command or with Emacs,
28018 and man pages are accessed using @command{man}.
28020 You can look for documentation of software installed on your system by
28021 keyword. For example, the following command searches for information
28022 about ``TLS'' in Info manuals:
28026 "(emacs)Network Security" -- STARTTLS
28027 "(emacs)Network Security" -- TLS
28028 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
28029 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
28034 The command below searches for the same keyword in man pages:
28038 SSL (7) - OpenSSL SSL/TLS library
28039 certtool (1) - GnuTLS certificate tool
28043 These searches are purely local to your computer so you have the
28044 guarantee that documentation you find corresponds to what you have
28045 actually installed, you can access it off-line, and your privacy is
28048 Once you have these results, you can view the relevant documentation by
28052 $ info "(gnutls)Core TLS API"
28062 Info manuals contain sections and indices as well as hyperlinks like
28063 those found in Web pages. The @command{info} reader (@pxref{Top, Info
28064 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
28065 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
28066 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
28067 Introduction}, for an introduction to Info navigation.
28069 @node Installing Debugging Files
28070 @chapter Installing Debugging Files
28072 @cindex debugging files
28073 Program binaries, as produced by the GCC compilers for instance, are
28074 typically written in the ELF format, with a section containing
28075 @dfn{debugging information}. Debugging information is what allows the
28076 debugger, GDB, to map binary code to source code; it is required to
28077 debug a compiled program in good conditions.
28079 The problem with debugging information is that is takes up a fair amount
28080 of disk space. For example, debugging information for the GNU C Library
28081 weighs in at more than 60 MiB. Thus, as a user, keeping all the
28082 debugging info of all the installed programs is usually not an option.
28083 Yet, space savings should not come at the cost of an impediment to
28084 debugging---especially in the GNU system, which should make it easier
28085 for users to exert their computing freedom (@pxref{GNU Distribution}).
28087 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
28088 mechanism that allows users to get the best of both worlds: debugging
28089 information can be stripped from the binaries and stored in separate
28090 files. GDB is then able to load debugging information from those files,
28091 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
28094 The GNU distribution takes advantage of this by storing debugging
28095 information in the @code{lib/debug} sub-directory of a separate package
28096 output unimaginatively called @code{debug} (@pxref{Packages with
28097 Multiple Outputs}). Users can choose to install the @code{debug} output
28098 of a package when they need it. For instance, the following command
28099 installs the debugging information for the GNU C Library and for GNU
28103 guix install glibc:debug guile:debug
28106 GDB must then be told to look for debug files in the user's profile, by
28107 setting the @code{debug-file-directory} variable (consider setting it
28108 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
28112 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
28115 From there on, GDB will pick up debugging information from the
28116 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
28118 In addition, you will most likely want GDB to be able to show the source
28119 code being debugged. To do that, you will have to unpack the source
28120 code of the package of interest (obtained with @code{guix build
28121 --source}, @pxref{Invoking guix build}), and to point GDB to that source
28122 directory using the @code{directory} command (@pxref{Source Path,
28123 @code{directory},, gdb, Debugging with GDB}).
28125 @c XXX: keep me up-to-date
28126 The @code{debug} output mechanism in Guix is implemented by the
28127 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
28128 opt-in---debugging information is available only for the packages
28129 with definitions explicitly declaring a @code{debug} output. This may be
28130 changed to opt-out in the future if our build farm servers can handle
28131 the load. To check whether a package has a @code{debug} output, use
28132 @command{guix package --list-available} (@pxref{Invoking guix package}).
28135 @node Security Updates
28136 @chapter Security Updates
28138 @cindex security updates
28139 @cindex security vulnerabilities
28140 Occasionally, important security vulnerabilities are discovered in software
28141 packages and must be patched. Guix developers try hard to keep track of
28142 known vulnerabilities and to apply fixes as soon as possible in the
28143 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
28144 containing only security updates.) The @command{guix lint} tool helps
28145 developers find out about vulnerable versions of software packages in the
28150 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
28151 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
28152 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
28156 @xref{Invoking guix lint}, for more information.
28158 Guix follows a functional
28159 package management discipline (@pxref{Introduction}), which implies
28160 that, when a package is changed, @emph{every package that depends on it}
28161 must be rebuilt. This can significantly slow down the deployment of
28162 fixes in core packages such as libc or Bash, since basically the whole
28163 distribution would need to be rebuilt. Using pre-built binaries helps
28164 (@pxref{Substitutes}), but deployment may still take more time than
28168 To address this, Guix implements @dfn{grafts}, a mechanism that allows
28169 for fast deployment of critical updates without the costs associated
28170 with a whole-distribution rebuild. The idea is to rebuild only the
28171 package that needs to be patched, and then to ``graft'' it onto packages
28172 explicitly installed by the user and that were previously referring to
28173 the original package. The cost of grafting is typically very low, and
28174 order of magnitudes lower than a full rebuild of the dependency chain.
28176 @cindex replacements of packages, for grafts
28177 For instance, suppose a security update needs to be applied to Bash.
28178 Guix developers will provide a package definition for the ``fixed''
28179 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
28180 Packages}). Then, the original package definition is augmented with a
28181 @code{replacement} field pointing to the package containing the bug fix:
28188 (replacement bash-fixed)))
28191 From there on, any package depending directly or indirectly on Bash---as
28192 reported by @command{guix gc --requisites} (@pxref{Invoking guix
28193 gc})---that is installed is automatically ``rewritten'' to refer to
28194 @code{bash-fixed} instead of @code{bash}. This grafting process takes
28195 time proportional to the size of the package, usually less than a
28196 minute for an ``average'' package on a recent machine. Grafting is
28197 recursive: when an indirect dependency requires grafting, then grafting
28198 ``propagates'' up to the package that the user is installing.
28200 Currently, the length of the name and version of the graft and that of
28201 the package it replaces (@code{bash-fixed} and @code{bash} in the example
28202 above) must be equal. This restriction mostly comes from the fact that
28203 grafting works by patching files, including binary files, directly.
28204 Other restrictions may apply: for instance, when adding a graft to a
28205 package providing a shared library, the original shared library and its
28206 replacement must have the same @code{SONAME} and be binary-compatible.
28208 The @option{--no-grafts} command-line option allows you to forcefully
28209 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
28213 guix build bash --no-grafts
28217 returns the store file name of the original Bash, whereas:
28224 returns the store file name of the ``fixed'', replacement Bash. This
28225 allows you to distinguish between the two variants of Bash.
28227 To verify which Bash your whole profile refers to, you can run
28228 (@pxref{Invoking guix gc}):
28231 guix gc -R `readlink -f ~/.guix-profile` | grep bash
28235 @dots{} and compare the store file names that you get with those above.
28236 Likewise for a complete Guix system generation:
28239 guix gc -R `guix system build my-config.scm` | grep bash
28242 Lastly, to check which Bash running processes are using, you can use the
28243 @command{lsof} command:
28246 lsof | grep /gnu/store/.*bash
28250 @node Bootstrapping
28251 @chapter Bootstrapping
28253 @c Adapted from the ELS 2013 paper.
28255 @cindex bootstrapping
28257 Bootstrapping in our context refers to how the distribution gets built
28258 ``from nothing''. Remember that the build environment of a derivation
28259 contains nothing but its declared inputs (@pxref{Introduction}). So
28260 there's an obvious chicken-and-egg problem: how does the first package
28261 get built? How does the first compiler get compiled? Note that this is
28262 a question of interest only to the curious hacker, not to the regular
28263 user, so you can shamelessly skip this section if you consider yourself
28264 a ``regular user''.
28266 @cindex bootstrap binaries
28267 The GNU system is primarily made of C code, with libc at its core. The
28268 GNU build system itself assumes the availability of a Bourne shell and
28269 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
28270 `grep'. Furthermore, build programs---programs that run
28271 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
28272 (@pxref{Derivations}). Consequently, to be able to build anything at
28273 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
28274 Binutils, libc, and the other packages mentioned above---the
28275 @dfn{bootstrap binaries}.
28277 These bootstrap binaries are ``taken for granted'', though we can also
28278 re-create them if needed (more on that later).
28280 For @code{i686-linux} and @code{x86_64-linux} the Guix bootstrap process is
28281 more elaborate, @pxref{Reduced Binary Seed Bootstrap}.
28284 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
28285 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
28288 @node Reduced Binary Seed Bootstrap
28289 @section The Reduced Binary Seed Bootstrap
28291 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
28292 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
28293 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
28294 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
28295 ``taken for granted.''
28297 Taking these binaries for granted means that we consider them to be a correct
28298 and trustworthy `seed' for building the complete system. Therein lies a
28299 problem: the current combined size of these bootstrap binaries is about 250MB
28300 (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing or even inspecting
28301 these is next to impossible.
28303 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a ``Reduced
28304 Binary Seed'' bootstrap @footnote{We would like to say: ``Full Source
28305 Bootstrap'' and while we are working towards that goal it would be hyperbole
28306 to use that term for what we do now.}.
28308 The Reduced Binary Seed bootstrap removes the most critical tools---from a
28309 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
28310 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
28311 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
28312 written in Scheme and the Mes C Library, built for TinyCC and for GCC). Using
28313 these new binary seeds and a new set of
28315 packages@footnote{@c
28330 gcc-mesboot1-wrapper,
28331 glibc-headers-mesboot,
28335 gcc-mesboot-wrapper.
28338 the ``missing'' Binutils, GCC, and the GNU C Library are built from source.
28339 From here on the more traditional bootstrap process resumes. This approach
28340 has reduced the bootstrap binaries in size to about 130MB. Work is ongoing to
28341 reduce this further. If you are interested, join us on @code{#bootstrappable}
28342 on the Freenode IRC network.
28344 @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
28345 @c dot -T png doc/images/gcc-mesboot-bag-graph.dot > doc/images/gcc-mesboot-bag-graph.png
28347 Below is the generated dependency graph for @code{gcc-mesboot}, the bootstrap
28348 compiler used to build the rest of GuixSD.
28350 @image{images/gcc-mesboot-bag-graph,6in,,Dependency graph of the gcc-mesboot}
28352 @node Preparing to Use the Bootstrap Binaries
28353 @section Preparing to Use the Bootstrap Binaries
28355 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
28356 @c large image, it's hard to scroll. Oh well.
28357 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
28359 The figure above shows the very beginning of the dependency graph of the
28360 distribution, corresponding to the package definitions of the @code{(gnu
28361 packages bootstrap)} module. A similar figure can be generated with
28362 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
28365 guix graph -t derivation \
28366 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
28367 | dot -Tps > gcc.ps
28370 or, for the Reduced Binary Seed bootstrap
28373 guix graph -t derivation \
28374 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
28375 | dot -Tps > mes.ps
28378 At this level of detail, things are
28379 slightly complex. First, Guile itself consists of an ELF executable,
28380 along with many source and compiled Scheme files that are dynamically
28381 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
28382 tarball shown in this graph. This tarball is part of Guix's ``source''
28383 distribution, and gets inserted into the store with @code{add-to-store}
28384 (@pxref{The Store}).
28386 But how do we write a derivation that unpacks this tarball and adds it
28387 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
28388 derivation---the first one that gets built---uses @code{bash} as its
28389 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
28390 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
28391 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
28392 the Guix source distribution, whose sole purpose is to allow the Guile
28393 tarball to be unpacked.
28395 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
28396 Guile that can be used to run subsequent build programs. Its first task
28397 is to download tarballs containing the other pre-built binaries---this
28398 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
28399 @code{ftp-client.scm} are used for this purpose. The
28400 @code{module-import.drv} derivations import those modules in a directory
28401 in the store, using the original layout. The
28402 @code{module-import-compiled.drv} derivations compile those modules, and
28403 write them in an output directory with the right layout. This
28404 corresponds to the @code{#:modules} argument of
28405 @code{build-expression->derivation} (@pxref{Derivations}).
28407 Finally, the various tarballs are unpacked by the derivations
28408 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
28409 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
28410 point we have a working C tool chain.
28412 @unnumberedsec Building the Build Tools
28414 Bootstrapping is complete when we have a full tool chain that does not
28415 depend on the pre-built bootstrap tools discussed above. This
28416 no-dependency requirement is verified by checking whether the files of
28417 the final tool chain contain references to the @file{/gnu/store}
28418 directories of the bootstrap inputs. The process that leads to this
28419 ``final'' tool chain is described by the package definitions found in
28420 the @code{(gnu packages commencement)} module.
28422 The @command{guix graph} command allows us to ``zoom out'' compared to
28423 the graph above, by looking at the level of package objects instead of
28424 individual derivations---remember that a package may translate to
28425 several derivations, typically one derivation to download its source,
28426 one to build the Guile modules it needs, and one to actually build the
28427 package from source. The command:
28430 guix graph -t bag \
28431 -e '(@@@@ (gnu packages commencement)
28432 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
28436 produces the dependency graph leading to the ``final'' C
28437 library@footnote{You may notice the @code{glibc-intermediate} label,
28438 suggesting that it is not @emph{quite} final, but as a good
28439 approximation, we will consider it final.}, depicted below.
28441 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
28443 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
28444 The first tool that gets built with the bootstrap binaries is
28445 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
28446 for all the following packages. From there Findutils and Diffutils get
28449 Then come the first-stage Binutils and GCC, built as pseudo cross
28450 tools---i.e., with @code{--target} equal to @code{--host}. They are
28451 used to build libc. Thanks to this cross-build trick, this libc is
28452 guaranteed not to hold any reference to the initial tool chain.
28454 From there the final Binutils and GCC (not shown above) are built.
28456 from the final Binutils, and links programs against the just-built libc.
28457 This tool chain is used to build the other packages used by Guix and by
28458 the GNU Build System: Guile, Bash, Coreutils, etc.
28460 And voilà! At this point we have the complete set of build tools that
28461 the GNU Build System expects. These are in the @code{%final-inputs}
28462 variable of the @code{(gnu packages commencement)} module, and are
28463 implicitly used by any package that uses @code{gnu-build-system}
28464 (@pxref{Build Systems, @code{gnu-build-system}}).
28467 @unnumberedsec Building the Bootstrap Binaries
28469 @cindex bootstrap binaries
28470 Because the final tool chain does not depend on the bootstrap binaries,
28471 those rarely need to be updated. Nevertheless, it is useful to have an
28472 automated way to produce them, should an update occur, and this is what
28473 the @code{(gnu packages make-bootstrap)} module provides.
28475 The following command builds the tarballs containing the bootstrap binaries
28476 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
28477 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
28478 and Guile, and a tarball containing a mixture of Coreutils and other basic
28479 command-line tools):
28482 guix build bootstrap-tarballs
28485 The generated tarballs are those that should be referred to in the
28486 @code{(gnu packages bootstrap)} module mentioned at the beginning of
28489 Still here? Then perhaps by now you've started to wonder: when do we
28490 reach a fixed point? That is an interesting question! The answer is
28491 unknown, but if you would like to investigate further (and have
28492 significant computational and storage resources to do so), then let us
28495 @unnumberedsec Reducing the Set of Bootstrap Binaries
28497 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
28498 binary code! Why is that a problem? It's a problem because these big chunks
28499 of binary code are practically non-auditable, which makes it hard to establish
28500 what source code produced them. Every unauditable binary also leaves us
28501 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
28502 paper @emph{Reflections on Trusting Trust}.
28504 This is mitigated by the fact that our bootstrap binaries were generated
28505 from an earlier Guix revision. Nevertheless it lacks the level of
28506 transparency that we get in the rest of the package dependency graph,
28507 where Guix always gives us a source-to-binary mapping. Thus, our goal
28508 is to reduce the set of bootstrap binaries to the bare minimum.
28510 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
28511 on-going projects to do that. One of these is about replacing the
28512 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
28513 of increasing complexity, which could be built from source starting from
28514 a simple and auditable assembler.
28516 Our first major achievement is the replacement of of GCC, the GNU C Library
28517 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
28518 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
28519 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
28520 bootstrapped yet and thus we inject them as binary seeds. We call this the
28521 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
28522 binaries! Also, it has eliminated the C compiler binary; i686-linux and
28523 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
28525 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
28526 also looking at any other bootstrap binaries. Your help is welcome!
28529 @chapter Porting to a New Platform
28531 As discussed above, the GNU distribution is self-contained, and
28532 self-containment is achieved by relying on pre-built ``bootstrap
28533 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
28534 operating system kernel, CPU architecture, and application binary
28535 interface (ABI). Thus, to port the distribution to a platform that is
28536 not yet supported, one must build those bootstrap binaries, and update
28537 the @code{(gnu packages bootstrap)} module to use them on that platform.
28539 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
28540 When everything goes well, and assuming the GNU tool chain supports the
28541 target platform, this can be as simple as running a command like this
28545 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
28548 For this to work, the @code{glibc-dynamic-linker} procedure in
28549 @code{(gnu packages bootstrap)} must be augmented to return the right
28550 file name for libc's dynamic linker on that platform; likewise,
28551 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
28552 taught about the new platform.
28554 Once these are built, the @code{(gnu packages bootstrap)} module needs
28555 to be updated to refer to these binaries on the target platform. That
28556 is, the hashes and URLs of the bootstrap tarballs for the new platform
28557 must be added alongside those of the currently supported platforms. The
28558 bootstrap Guile tarball is treated specially: it is expected to be
28559 available locally, and @file{gnu/local.mk} has rules to download it for
28560 the supported architectures; a rule for the new platform must be added
28563 In practice, there may be some complications. First, it may be that the
28564 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
28565 above) is not recognized by all the GNU tools. Typically, glibc
28566 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
28567 configure flag (see @code{gcc.scm} for examples of how to handle this).
28568 Second, some of the required packages could fail to build for that
28569 platform. Lastly, the generated binaries could be broken for some
28572 @c *********************************************************************
28573 @include contributing.texi
28575 @c *********************************************************************
28576 @node Acknowledgments
28577 @chapter Acknowledgments
28579 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
28580 which was designed and
28581 implemented by Eelco Dolstra, with contributions from other people (see
28582 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
28583 management, and promoted unprecedented features, such as transactional
28584 package upgrades and rollbacks, per-user profiles, and referentially
28585 transparent build processes. Without this work, Guix would not exist.
28587 The Nix-based software distributions, Nixpkgs and NixOS, have also been
28588 an inspiration for Guix.
28590 GNU@tie{}Guix itself is a collective work with contributions from a
28591 number of people. See the @file{AUTHORS} file in Guix for more
28592 information on these fine people. The @file{THANKS} file lists people
28593 who have helped by reporting bugs, taking care of the infrastructure,
28594 providing artwork and themes, making suggestions, and more---thank you!
28597 @c *********************************************************************
28598 @node GNU Free Documentation License
28599 @appendix GNU Free Documentation License
28600 @cindex license, GNU Free Documentation License
28601 @include fdl-1.3.texi
28603 @c *********************************************************************
28604 @node Concept Index
28605 @unnumbered Concept Index
28608 @node Programming Index
28609 @unnumbered Programming Index
28610 @syncodeindex tp fn
28611 @syncodeindex vr fn
28616 @c Local Variables:
28617 @c ispell-local-dictionary: "american";