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 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 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@*
78 Permission is granted to copy, distribute and/or modify this document
79 under the terms of the GNU Free Documentation License, Version 1.3 or
80 any later version published by the Free Software Foundation; with no
81 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
82 copy of the license is included in the section entitled ``GNU Free
83 Documentation License''.
86 @dircategory System administration
88 * Guix: (guix). Manage installed software and system configuration.
89 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
90 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
91 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
92 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
93 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
96 @dircategory Software development
98 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
99 * guix build: (guix)Invoking guix build. Building packages.
100 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
104 @title GNU Guix Reference Manual
105 @subtitle Using the GNU Guix Functional Package Manager
106 @author The GNU Guix Developers
109 @vskip 0pt plus 1filll
110 Edition @value{EDITION} @*
118 @c *********************************************************************
122 This document describes GNU Guix version @value{VERSION}, a functional
123 package management tool written for the GNU system.
125 @c TRANSLATORS: You can replace the following paragraph with information on
126 @c how to join your own translation team and how to report issues with the
128 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
129 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
130 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
131 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
132 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
133 would like to translate it in your native language, consider joining the
134 @uref{https://translationproject.org/domain/guix-manual.html, Translation
138 * Introduction:: What is Guix about?
139 * Installation:: Installing Guix.
140 * System Installation:: Installing the whole operating system.
141 * Package Management:: Package installation, upgrade, etc.
142 * Development:: Guix-aided software development.
143 * Programming Interface:: Using Guix in Scheme.
144 * Utilities:: Package management commands.
145 * System Configuration:: Configuring the operating system.
146 * Documentation:: Browsing software user manuals.
147 * Installing Debugging Files:: Feeding the debugger.
148 * Security Updates:: Deploying security fixes quickly.
149 * Bootstrapping:: GNU/Linux built from scratch.
150 * Porting:: Targeting another platform or kernel.
151 * Contributing:: Your help needed!
153 * Acknowledgments:: Thanks!
154 * GNU Free Documentation License:: The license of this manual.
155 * Concept Index:: Concepts.
156 * Programming Index:: Data types, functions, and variables.
159 --- The Detailed Node Listing ---
163 * Managing Software the Guix Way:: What's special.
164 * GNU Distribution:: The packages and tools.
168 * Binary Installation:: Getting Guix running in no time!
169 * Requirements:: Software needed to build and run Guix.
170 * Running the Test Suite:: Testing Guix.
171 * Setting Up the Daemon:: Preparing the build daemon's environment.
172 * Invoking guix-daemon:: Running the build daemon.
173 * Application Setup:: Application-specific setup.
175 Setting Up the Daemon
177 * Build Environment Setup:: Preparing the isolated build environment.
178 * Daemon Offload Setup:: Offloading builds to remote machines.
179 * SELinux Support:: Using an SELinux policy for the daemon.
183 * Limitations:: What you can expect.
184 * Hardware Considerations:: Supported hardware.
185 * USB Stick and DVD Installation:: Preparing the installation medium.
186 * Preparing for Installation:: Networking, partitioning, etc.
187 * Guided Graphical Installation:: Easy graphical installation.
188 * Manual Installation:: Manual installation for wizards.
189 * After System Installation:: When installation succeeded.
190 * Installing Guix in a VM:: Guix System playground.
191 * Building the Installation Image:: How this comes to be.
195 * Keyboard Layout and Networking and Partitioning:: Initial setup.
196 * Proceeding with the Installation:: Installing.
200 * Features:: How Guix will make your life brighter.
201 * Invoking guix package:: Package installation, removal, etc.
202 * Substitutes:: Downloading pre-built binaries.
203 * Packages with Multiple Outputs:: Single source package, multiple outputs.
204 * Invoking guix gc:: Running the garbage collector.
205 * Invoking guix pull:: Fetching the latest Guix and distribution.
206 * Channels:: Customizing the package collection.
207 * Invoking guix time-machine:: Running an older revision of Guix.
208 * Inferiors:: Interacting with another revision of Guix.
209 * Invoking guix describe:: Display information about your Guix revision.
210 * Invoking guix archive:: Exporting and importing store files.
214 * Official Substitute Server:: One particular source of substitutes.
215 * Substitute Server Authorization:: How to enable or disable substitutes.
216 * Substitute Authentication:: How Guix verifies substitutes.
217 * Proxy Settings:: How to get substitutes via proxy.
218 * Substitution Failure:: What happens when substitution fails.
219 * On Trusting Binaries:: How can you trust that binary blob?
223 * Invoking guix environment:: Setting up development environments.
224 * Invoking guix pack:: Creating software bundles.
226 Programming Interface
228 * Package Modules:: Packages from the programmer's viewpoint.
229 * Defining Packages:: Defining new packages.
230 * Build Systems:: Specifying how packages are built.
231 * The Store:: Manipulating the package store.
232 * Derivations:: Low-level interface to package derivations.
233 * The Store Monad:: Purely functional interface to the store.
234 * G-Expressions:: Manipulating build expressions.
235 * Invoking guix repl:: Fiddling with Guix interactively.
239 * package Reference:: The package data type.
240 * origin Reference:: The origin data type.
244 * Invoking guix build:: Building packages from the command line.
245 * Invoking guix edit:: Editing package definitions.
246 * Invoking guix download:: Downloading a file and printing its hash.
247 * Invoking guix hash:: Computing the cryptographic hash of a file.
248 * Invoking guix import:: Importing package definitions.
249 * Invoking guix refresh:: Updating package definitions.
250 * Invoking guix lint:: Finding errors in package definitions.
251 * Invoking guix size:: Profiling disk usage.
252 * Invoking guix graph:: Visualizing the graph of packages.
253 * Invoking guix publish:: Sharing substitutes.
254 * Invoking guix challenge:: Challenging substitute servers.
255 * Invoking guix copy:: Copying to and from a remote store.
256 * Invoking guix container:: Process isolation.
257 * Invoking guix weather:: Assessing substitute availability.
258 * Invoking guix processes:: Listing client processes.
260 Invoking @command{guix build}
262 * Common Build Options:: Build options for most commands.
263 * Package Transformation Options:: Creating variants of packages.
264 * Additional Build Options:: Options specific to 'guix build'.
265 * Debugging Build Failures:: Real life packaging experience.
269 * Using the Configuration System:: Customizing your GNU system.
270 * operating-system Reference:: Detail of operating-system declarations.
271 * File Systems:: Configuring file system mounts.
272 * Mapped Devices:: Block device extra processing.
273 * User Accounts:: Specifying user accounts.
274 * Keyboard Layout:: How the system interprets key strokes.
275 * Locales:: Language and cultural convention settings.
276 * Services:: Specifying system services.
277 * Setuid Programs:: Programs running with root privileges.
278 * X.509 Certificates:: Authenticating HTTPS servers.
279 * Name Service Switch:: Configuring libc's name service switch.
280 * Initial RAM Disk:: Linux-Libre bootstrapping.
281 * Bootloader Configuration:: Configuring the boot loader.
282 * Invoking guix system:: Instantiating a system configuration.
283 * Invoking guix deploy:: Deploying a system configuration to a remote host.
284 * Running Guix in a VM:: How to run Guix System in a virtual machine.
285 * Defining Services:: Adding new service definitions.
289 * Base Services:: Essential system services.
290 * Scheduled Job Execution:: The mcron service.
291 * Log Rotation:: The rottlog service.
292 * Networking Services:: Network setup, SSH daemon, etc.
293 * X Window:: Graphical display.
294 * Printing Services:: Local and remote printer support.
295 * Desktop Services:: D-Bus and desktop services.
296 * Sound Services:: ALSA and Pulseaudio services.
297 * Database Services:: SQL databases, key-value stores, etc.
298 * Mail Services:: IMAP, POP3, SMTP, and all that.
299 * Messaging Services:: Messaging services.
300 * Telephony Services:: Telephony services.
301 * Monitoring Services:: Monitoring services.
302 * Kerberos Services:: Kerberos services.
303 * Web Services:: Web servers.
304 * Certificate Services:: TLS certificates via Let's Encrypt.
305 * DNS Services:: DNS daemons.
306 * VPN Services:: VPN daemons.
307 * Network File System:: NFS related services.
308 * Continuous Integration:: The Cuirass service.
309 * Power Management Services:: Extending battery life.
310 * Audio Services:: The MPD.
311 * Virtualization Services:: Virtualization services.
312 * Version Control Services:: Providing remote access to Git repositories.
313 * Game Services:: Game servers.
314 * PAM Mount Service:: Service to mount volumes when logging in.
315 * Linux Services:: Services tied to the Linux kernel.
316 * Miscellaneous Services:: Other services.
320 * Service Composition:: The model for composing services.
321 * Service Types and Services:: Types and services.
322 * Service Reference:: API reference.
323 * Shepherd Services:: A particular type of service.
328 @c *********************************************************************
330 @chapter Introduction
333 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
334 using the international phonetic alphabet (IPA).} is a package
335 management tool for and distribution of the GNU system.
336 Guix makes it easy for unprivileged
337 users to install, upgrade, or remove software packages, to roll back to a
338 previous package set, to build packages from source, and generally
339 assists with the creation and maintenance of software environments.
342 @cindex GuixSD, now Guix System
343 @cindex Guix System Distribution, now Guix System
344 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
345 complements the available tools without interference (@pxref{Installation}),
346 or you can use it as a standalone operating system distribution,
347 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
348 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
349 group everything under the ``Guix'' banner since, after all, Guix System is
350 readily available through the @command{guix system} command, even if you're
351 using a different distro underneath!}. @xref{GNU Distribution}.
354 * Managing Software the Guix Way:: What's special.
355 * GNU Distribution:: The packages and tools.
358 @node Managing Software the Guix Way
359 @section Managing Software the Guix Way
361 @cindex user interfaces
362 Guix provides a command-line package management interface
363 (@pxref{Package Management}), tools to help with software development
364 (@pxref{Development}), command-line utilities for more advanced usage,
365 (@pxref{Utilities}), as well as Scheme programming interfaces
366 (@pxref{Programming Interface}).
368 Its @dfn{build daemon} is responsible for building packages on behalf of
369 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
370 binaries from authorized sources (@pxref{Substitutes}).
372 @cindex extensibility of the distribution
373 @cindex customization, of packages
374 Guix includes package definitions for many GNU and non-GNU packages, all
375 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
376 user's computing freedom}. It is @emph{extensible}: users can write
377 their own package definitions (@pxref{Defining Packages}) and make them
378 available as independent package modules (@pxref{Package Modules}). It
379 is also @emph{customizable}: users can @emph{derive} specialized package
380 definitions from existing ones, including from the command line
381 (@pxref{Package Transformation Options}).
383 @cindex functional package management
385 Under the hood, Guix implements the @dfn{functional package management}
386 discipline pioneered by Nix (@pxref{Acknowledgments}).
387 In Guix, the package build and installation process is seen
388 as a @emph{function}, in the mathematical sense. That function takes inputs,
389 such as build scripts, a compiler, and libraries, and
390 returns an installed package. As a pure function, its result depends
391 solely on its inputs---for instance, it cannot refer to software or
392 scripts that were not explicitly passed as inputs. A build function
393 always produces the same result when passed a given set of inputs. It
394 cannot alter the environment of the running system in
395 any way; for instance, it cannot create, modify, or delete files outside
396 of its build and installation directories. This is achieved by running
397 build processes in isolated environments (or @dfn{containers}), where only their
398 explicit inputs are visible.
401 The result of package build functions is @dfn{cached} in the file
402 system, in a special directory called @dfn{the store} (@pxref{The
403 Store}). Each package is installed in a directory of its own in the
404 store---by default under @file{/gnu/store}. The directory name contains
405 a hash of all the inputs used to build that package; thus, changing an
406 input yields a different directory name.
408 This approach is the foundation for the salient features of Guix: support
409 for transactional package upgrade and rollback, per-user installation, and
410 garbage collection of packages (@pxref{Features}).
413 @node GNU Distribution
414 @section GNU Distribution
417 Guix comes with a distribution of the GNU system consisting entirely of
418 free software@footnote{The term ``free'' here refers to the
419 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
420 users of that software}.}. The
421 distribution can be installed on its own (@pxref{System Installation}),
422 but it is also possible to install Guix as a package manager on top of
423 an installed GNU/Linux system (@pxref{Installation}). When we need to
424 distinguish between the two, we refer to the standalone distribution as
427 The distribution provides core GNU packages such as GNU libc, GCC, and
428 Binutils, as well as many GNU and non-GNU applications. The complete
429 list of available packages can be browsed
430 @url{https://www.gnu.org/software/guix/packages,on-line} or by
431 running @command{guix package} (@pxref{Invoking guix package}):
434 guix package --list-available
437 Our goal is to provide a practical 100% free software distribution of
438 Linux-based and other variants of GNU, with a focus on the promotion and
439 tight integration of GNU components, and an emphasis on programs and
440 tools that help users exert that freedom.
442 Packages are currently available on the following platforms:
447 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
450 Intel 32-bit architecture (IA32), Linux-Libre kernel;
453 ARMv7-A architecture with hard float, Thumb-2 and NEON,
454 using the EABI hard-float application binary interface (ABI),
455 and Linux-Libre kernel.
458 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
461 little-endian 64-bit MIPS processors, specifically the Loongson series,
462 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
463 supported; in particular, the project's build farms no longer provide
464 substitutes for this architecture.
468 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
469 configuration and Guix takes care of instantiating the configuration in a
470 transactional, reproducible, and stateless fashion (@pxref{System
471 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
472 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
473 Manual}), the well-known GNU utilities and tool chain, as well as the
474 graphical environment or system services of your choice.
476 Guix System is available on all the above platforms except
477 @code{mips64el-linux}.
480 For information on porting to other architectures or kernels,
483 Building this distribution is a cooperative effort, and you are invited
484 to join! @xref{Contributing}, for information about how you can help.
487 @c *********************************************************************
489 @chapter Installation
491 @cindex installing Guix
494 We recommend the use of this
495 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
496 shell installer script} to install Guix on top of a running GNU/Linux system,
497 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
498 with the installation of the package manager, which can be done on top of a
499 running GNU/Linux system. If, instead, you want to install the complete GNU
500 operating system, @pxref{System Installation}.} The script automates the
501 download, installation, and initial configuration of Guix. It should be run
505 @cindex foreign distro
506 @cindex directories related to foreign distro
507 When installed on a foreign distro, GNU@tie{}Guix complements the available
508 tools without interference. Its data lives exclusively in two directories,
509 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
510 such as @file{/etc}, are left untouched.
512 Once installed, Guix can be updated by running @command{guix pull}
513 (@pxref{Invoking guix pull}).
515 If you prefer to perform the installation steps manually or want to tweak
516 them, you may find the following subsections useful. They describe the
517 software requirements of Guix, as well as how to install it manually and get
521 * Binary Installation:: Getting Guix running in no time!
522 * Requirements:: Software needed to build and run Guix.
523 * Running the Test Suite:: Testing Guix.
524 * Setting Up the Daemon:: Preparing the build daemon's environment.
525 * Invoking guix-daemon:: Running the build daemon.
526 * Application Setup:: Application-specific setup.
527 * Upgrading Guix:: Upgrading Guix and its build daemon.
530 @node Binary Installation
531 @section Binary Installation
533 @cindex installing Guix from binaries
534 @cindex installer script
535 This section describes how to install Guix on an arbitrary system from a
536 self-contained tarball providing binaries for Guix and for all its
537 dependencies. This is often quicker than installing from source, which
538 is described in the next sections. The only requirement is to have
541 @c Note duplicated from the ``Installation'' node.
543 We recommend the use of this
544 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
545 shell installer script}. The script automates the download, installation, and
546 initial configuration steps described below. It should be run as the root
550 Installing goes along these lines:
554 @cindex downloading Guix binary
555 Download the binary tarball from
556 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz},
557 where @var{system} is @code{x86_64-linux} for an @code{x86_64} machine
558 already running the kernel Linux, and so on.
560 @c The following is somewhat duplicated in ``System Installation''.
561 Make sure to download the associated @file{.sig} file and to verify the
562 authenticity of the tarball against it, along these lines:
565 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
566 $ gpg --verify guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
569 If that command fails because you do not have the required public key,
570 then run this command to import it:
573 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
574 -qO - | gpg --import -
578 and rerun the @code{gpg --verify} command.
580 Take note that a warning like ``This key is not certified with a trusted
581 signature!'' is normal.
583 @c end authentication part
586 Now, you need to become the @code{root} user. Depending on your distribution,
587 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
591 # tar --warning=no-timestamp -xf \
592 /path/to/guix-binary-@value{VERSION}.@var{system}.tar.xz
593 # mv var/guix /var/ && mv gnu /
596 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
597 The latter contains a ready-to-use profile for @code{root} (see next
600 Do @emph{not} unpack the tarball on a working Guix system since that
601 would overwrite its own essential files.
603 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
604 not emit warnings about ``implausibly old time stamps'' (such
605 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
607 They stem from the fact that all the
608 files in the archive have their modification time set to zero (which
609 means January 1st, 1970.) This is done on purpose to make sure the
610 archive content is independent of its creation time, thus making it
614 Make the profile available under @file{~root/.config/guix/current}, which is
615 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
618 # mkdir -p ~root/.config/guix
619 # ln -sf /var/guix/profiles/per-user/root/current-guix \
620 ~root/.config/guix/current
623 Source @file{etc/profile} to augment @code{PATH} and other relevant
624 environment variables:
627 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
628 source $GUIX_PROFILE/etc/profile
632 Create the group and user accounts for build users as explained below
633 (@pxref{Build Environment Setup}).
636 Run the daemon, and set it to automatically start on boot.
638 If your host distro uses the systemd init system, this can be achieved
641 @c Versions of systemd that supported symlinked service files are not
642 @c yet widely deployed, so we should suggest that users copy the service
645 @c See this thread for more information:
646 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
649 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
651 # systemctl start guix-daemon && systemctl enable guix-daemon
654 If your host distro uses the Upstart init system:
657 # initctl reload-configuration
658 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
663 Otherwise, you can still start the daemon manually with:
666 # ~root/.config/guix/current/bin/guix-daemon \
667 --build-users-group=guixbuild
671 Make the @command{guix} command available to other users on the machine,
675 # mkdir -p /usr/local/bin
677 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
680 It is also a good idea to make the Info version of this manual available
684 # mkdir -p /usr/local/share/info
685 # cd /usr/local/share/info
686 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
690 That way, assuming @file{/usr/local/share/info} is in the search path,
691 running @command{info guix} will open this manual (@pxref{Other Info
692 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
696 @cindex substitutes, authorization thereof
697 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
698 (@pxref{Substitutes}), authorize them:
701 # guix archive --authorize < \
702 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
706 Each user may need to perform a few additional steps to make their Guix
707 environment ready for use, @pxref{Application Setup}.
710 Voilà, the installation is complete!
712 You can confirm that Guix is working by installing a sample package into
719 The binary installation tarball can be (re)produced and verified simply
720 by running the following command in the Guix source tree:
723 make guix-binary.@var{system}.tar.xz
727 ...@: which, in turn, runs:
730 guix pack -s @var{system} --localstatedir \
731 --profile-name=current-guix guix
734 @xref{Invoking guix pack}, for more info on this handy tool.
737 @section Requirements
739 This section lists requirements when building Guix from source. The
740 build procedure for Guix is the same as for other GNU software, and is
741 not covered here. Please see the files @file{README} and @file{INSTALL}
742 in the Guix source tree for additional details.
744 @cindex official website
745 GNU Guix is available for download from its website at
746 @url{https://www.gnu.org/software/guix/}.
748 GNU Guix depends on the following packages:
751 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
753 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
756 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
757 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
758 Guile,, gnutls-guile, GnuTLS-Guile});
760 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
763 @c FIXME: Specify a version number once a release has been made.
764 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
766 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON} 3.x;
767 @item @url{https://zlib.net, zlib};
768 @item @url{https://www.gnu.org/software/make/, GNU Make}.
771 The following dependencies are optional:
775 @c Note: We need at least 0.12.0 for 'userauth-gssapi!'.
776 Support for build offloading (@pxref{Daemon Offload Setup}) and
777 @command{guix copy} (@pxref{Invoking guix copy}) depends on
778 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
779 version 0.12.0 or later.
782 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
783 substitutes can be used and @command{guix publish} can compress substitutes
787 When @url{http://www.bzip.org, libbz2} is available,
788 @command{guix-daemon} can use it to compress build logs.
791 Unless @code{--disable-daemon} was passed to @command{configure}, the
792 following packages are also needed:
795 @item @url{https://gnupg.org/, GNU libgcrypt};
796 @item @url{https://sqlite.org, SQLite 3};
797 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
801 @cindex state directory
802 When configuring Guix on a system that already has a Guix installation,
803 be sure to specify the same state directory as the existing installation
804 using the @code{--localstatedir} option of the @command{configure}
805 script (@pxref{Directory Variables, @code{localstatedir},, standards,
806 GNU Coding Standards}). Usually, this @var{localstatedir} option is
807 set to the value @file{/var}. The @command{configure} script protects
808 against unintended misconfiguration of @var{localstatedir} so you do not
809 inadvertently corrupt your store (@pxref{The Store}).
811 @node Running the Test Suite
812 @section Running the Test Suite
815 After a successful @command{configure} and @code{make} run, it is a good
816 idea to run the test suite. It can help catch issues with the setup or
817 environment, or bugs in Guix itself---and really, reporting test
818 failures is a good way to help improve the software. To run the test
825 Test cases can run in parallel: you can use the @code{-j} option of
826 GNU@tie{}make to speed things up. The first run may take a few minutes
827 on a recent machine; subsequent runs will be faster because the store
828 that is created for test purposes will already have various things in
831 It is also possible to run a subset of the tests by defining the
832 @code{TESTS} makefile variable as in this example:
835 make check TESTS="tests/store.scm tests/cpio.scm"
838 By default, tests results are displayed at a file level. In order to
839 see the details of every individual test cases, it is possible to define
840 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
843 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
846 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
847 @file{test-suite.log} file. Please specify the Guix version being used
848 as well as version numbers of the dependencies (@pxref{Requirements}) in
851 Guix also comes with a whole-system test suite that tests complete
852 Guix System instances. It can only run on systems where
853 Guix is already installed, using:
860 or, again, by defining @code{TESTS} to select a subset of tests to run:
863 make check-system TESTS="basic mcron"
866 These system tests are defined in the @code{(gnu tests @dots{})}
867 modules. They work by running the operating systems under test with
868 lightweight instrumentation in a virtual machine (VM). They can be
869 computationally intensive or rather cheap, depending on whether
870 substitutes are available for their dependencies (@pxref{Substitutes}).
871 Some of them require a lot of storage space to hold VM images.
873 Again in case of test failures, please send @email{bug-guix@@gnu.org}
876 @node Setting Up the Daemon
877 @section Setting Up the Daemon
880 Operations such as building a package or running the garbage collector
881 are all performed by a specialized process, the @dfn{build daemon}, on
882 behalf of clients. Only the daemon may access the store and its
883 associated database. Thus, any operation that manipulates the store
884 goes through the daemon. For instance, command-line tools such as
885 @command{guix package} and @command{guix build} communicate with the
886 daemon (@i{via} remote procedure calls) to instruct it what to do.
888 The following sections explain how to prepare the build daemon's
889 environment. See also @ref{Substitutes}, for information on how to allow
890 the daemon to download pre-built binaries.
893 * Build Environment Setup:: Preparing the isolated build environment.
894 * Daemon Offload Setup:: Offloading builds to remote machines.
895 * SELinux Support:: Using an SELinux policy for the daemon.
898 @node Build Environment Setup
899 @subsection Build Environment Setup
901 @cindex build environment
902 In a standard multi-user setup, Guix and its daemon---the
903 @command{guix-daemon} program---are installed by the system
904 administrator; @file{/gnu/store} is owned by @code{root} and
905 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
906 Guix tools to build packages or otherwise access the store, and the
907 daemon will do it on their behalf, ensuring that the store is kept in a
908 consistent state, and allowing built packages to be shared among users.
911 When @command{guix-daemon} runs as @code{root}, you may not want package
912 build processes themselves to run as @code{root} too, for obvious
913 security reasons. To avoid that, a special pool of @dfn{build users}
914 should be created for use by build processes started by the daemon.
915 These build users need not have a shell and a home directory: they will
916 just be used when the daemon drops @code{root} privileges in build
917 processes. Having several such users allows the daemon to launch
918 distinct build processes under separate UIDs, which guarantees that they
919 do not interfere with each other---an essential feature since builds are
920 regarded as pure functions (@pxref{Introduction}).
922 On a GNU/Linux system, a build user pool may be created like this (using
923 Bash syntax and the @code{shadow} commands):
925 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
926 @c for why `-G' is needed.
928 # groupadd --system guixbuild
929 # for i in `seq -w 1 10`;
931 useradd -g guixbuild -G guixbuild \
932 -d /var/empty -s `which nologin` \
933 -c "Guix build user $i" --system \
939 The number of build users determines how many build jobs may run in
940 parallel, as specified by the @option{--max-jobs} option
941 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
942 @command{guix system vm} and related commands, you may need to add the
943 build users to the @code{kvm} group so they can access @file{/dev/kvm},
944 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
945 (@pxref{Invoking guix system}).
947 The @code{guix-daemon} program may then be run as @code{root} with the
948 following command@footnote{If your machine uses the systemd init system,
949 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
950 file in @file{/etc/systemd/system} will ensure that
951 @command{guix-daemon} is automatically started. Similarly, if your
952 machine uses the Upstart init system, drop the
953 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
954 file in @file{/etc/init}.}:
957 # guix-daemon --build-users-group=guixbuild
962 This way, the daemon starts build processes in a chroot, under one of
963 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
964 environment contains nothing but:
966 @c Keep this list in sync with libstore/build.cc! -----------------------
969 a minimal @code{/dev} directory, created mostly independently from the
970 host @code{/dev}@footnote{``Mostly'', because while the set of files
971 that appear in the chroot's @code{/dev} is fixed, most of these files
972 can only be created if the host has them.};
975 the @code{/proc} directory; it only shows the processes of the container
976 since a separate PID name space is used;
979 @file{/etc/passwd} with an entry for the current user and an entry for
983 @file{/etc/group} with an entry for the user's group;
986 @file{/etc/hosts} with an entry that maps @code{localhost} to
990 a writable @file{/tmp} directory.
993 You can influence the directory where the daemon stores build trees
994 @i{via} the @code{TMPDIR} environment variable. However, the build tree
995 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
996 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
997 This way, the value of @code{TMPDIR} does not leak inside build
998 environments, which avoids discrepancies in cases where build processes
999 capture the name of their build tree.
1002 The daemon also honors the @code{http_proxy} environment variable for
1003 HTTP downloads it performs, be it for fixed-output derivations
1004 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1006 If you are installing Guix as an unprivileged user, it is still possible
1007 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1008 However, build processes will not be isolated from one another, and not
1009 from the rest of the system. Thus, build processes may interfere with
1010 each other, and may access programs, libraries, and other files
1011 available on the system---making it much harder to view them as
1012 @emph{pure} functions.
1015 @node Daemon Offload Setup
1016 @subsection Using the Offload Facility
1020 When desired, the build daemon can @dfn{offload} derivation builds to
1021 other machines running Guix, using the @code{offload} @dfn{build
1022 hook}@footnote{This feature is available only when
1023 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1024 present.}. When that
1025 feature is enabled, a list of user-specified build machines is read from
1026 @file{/etc/guix/machines.scm}; every time a build is requested, for
1027 instance via @code{guix build}, the daemon attempts to offload it to one
1028 of the machines that satisfy the constraints of the derivation, in
1029 particular its system type---e.g., @file{x86_64-linux}. Missing
1030 prerequisites for the build are copied over SSH to the target machine,
1031 which then proceeds with the build; upon success the output(s) of the
1032 build are copied back to the initial machine.
1034 The @file{/etc/guix/machines.scm} file typically looks like this:
1037 (list (build-machine
1038 (name "eightysix.example.org")
1039 (system "x86_64-linux")
1040 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1042 (speed 2.)) ;incredibly fast!
1045 (name "meeps.example.org")
1046 (system "mips64el-linux")
1047 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1050 (string-append (getenv "HOME")
1051 "/.ssh/identity-for-guix"))))
1055 In the example above we specify a list of two build machines, one for
1056 the @code{x86_64} architecture and one for the @code{mips64el}
1059 In fact, this file is---not surprisingly!---a Scheme file that is
1060 evaluated when the @code{offload} hook is started. Its return value
1061 must be a list of @code{build-machine} objects. While this example
1062 shows a fixed list of build machines, one could imagine, say, using
1063 DNS-SD to return a list of potential build machines discovered in the
1064 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1065 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1068 @deftp {Data Type} build-machine
1069 This data type represents build machines to which the daemon may offload
1070 builds. The important fields are:
1075 The host name of the remote machine.
1078 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1081 The user account to use when connecting to the remote machine over SSH.
1082 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1083 allow non-interactive logins.
1086 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1087 This is used to authenticate the machine when we connect to it. It is a
1088 long string that looks like this:
1091 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1094 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1095 key can be found in a file such as
1096 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1098 If the machine is running the SSH daemon of GNU@tie{}lsh,
1099 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1100 similar file. It can be converted to the OpenSSH format using
1101 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1104 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1105 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1110 A number of optional fields may be specified:
1114 @item @code{port} (default: @code{22})
1115 Port number of SSH server on the machine.
1117 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1118 The SSH private key file to use when connecting to the machine, in
1119 OpenSSH format. This key must not be protected with a passphrase.
1121 Note that the default value is the private key @emph{of the root
1122 account}. Make sure it exists if you use the default.
1124 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1125 @itemx @code{compression-level} (default: @code{3})
1126 The SSH-level compression methods and compression level requested.
1128 Note that offloading relies on SSH compression to reduce bandwidth usage
1129 when transferring files to and from build machines.
1131 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1132 File name of the Unix-domain socket @command{guix-daemon} is listening
1135 @item @code{parallel-builds} (default: @code{1})
1136 The number of builds that may run in parallel on the machine.
1138 @item @code{speed} (default: @code{1.0})
1139 A ``relative speed factor''. The offload scheduler will tend to prefer
1140 machines with a higher speed factor.
1142 @item @code{features} (default: @code{'()})
1143 A list of strings denoting specific features supported by the machine.
1144 An example is @code{"kvm"} for machines that have the KVM Linux modules
1145 and corresponding hardware support. Derivations can request features by
1146 name, and they will be scheduled on matching build machines.
1151 The @command{guix} command must be in the search path on the build
1152 machines. You can check whether this is the case by running:
1155 ssh build-machine guix repl --version
1158 There is one last thing to do once @file{machines.scm} is in place. As
1159 explained above, when offloading, files are transferred back and forth
1160 between the machine stores. For this to work, you first need to
1161 generate a key pair on each machine to allow the daemon to export signed
1162 archives of files from the store (@pxref{Invoking guix archive}):
1165 # guix archive --generate-key
1169 Each build machine must authorize the key of the master machine so that
1170 it accepts store items it receives from the master:
1173 # guix archive --authorize < master-public-key.txt
1177 Likewise, the master machine must authorize the key of each build machine.
1179 All the fuss with keys is here to express pairwise mutual trust
1180 relations between the master and the build machines. Concretely, when
1181 the master receives files from a build machine (and @i{vice versa}), its
1182 build daemon can make sure they are genuine, have not been tampered
1183 with, and that they are signed by an authorized key.
1185 @cindex offload test
1186 To test whether your setup is operational, run this command on the
1193 This will attempt to connect to each of the build machines specified in
1194 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1195 available on each machine, attempt to export to the machine and import
1196 from it, and report any error in the process.
1198 If you want to test a different machine file, just specify it on the
1202 # guix offload test machines-qualif.scm
1205 Last, you can test the subset of the machines whose name matches a
1206 regular expression like this:
1209 # guix offload test machines.scm '\.gnu\.org$'
1212 @cindex offload status
1213 To display the current load of all build hosts, run this command on the
1217 # guix offload status
1221 @node SELinux Support
1222 @subsection SELinux Support
1224 @cindex SELinux, daemon policy
1225 @cindex mandatory access control, SELinux
1226 @cindex security, guix-daemon
1227 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1228 can be installed on a system where SELinux is enabled, in order to label
1229 Guix files and to specify the expected behavior of the daemon. Since
1230 Guix System does not provide an SELinux base policy, the daemon policy cannot
1231 be used on Guix System.
1233 @subsubsection Installing the SELinux policy
1234 @cindex SELinux, policy installation
1235 To install the policy run this command as root:
1238 semodule -i etc/guix-daemon.cil
1241 Then relabel the file system with @code{restorecon} or by a different
1242 mechanism provided by your system.
1244 Once the policy is installed, the file system has been relabeled, and
1245 the daemon has been restarted, it should be running in the
1246 @code{guix_daemon_t} context. You can confirm this with the following
1250 ps -Zax | grep guix-daemon
1253 Monitor the SELinux log files as you run a command like @code{guix build
1254 hello} to convince yourself that SELinux permits all necessary
1257 @subsubsection Limitations
1258 @cindex SELinux, limitations
1260 This policy is not perfect. Here is a list of limitations or quirks
1261 that should be considered when deploying the provided SELinux policy for
1266 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1267 operations involve contexts that have anything to do with
1268 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1269 but it would be preferrable to define socket rules for only this label.
1272 @code{guix gc} cannot access arbitrary links to profiles. By design,
1273 the file label of the destination of a symlink is independent of the
1274 file label of the link itself. Although all profiles under
1275 $localstatedir are labelled, the links to these profiles inherit the
1276 label of the directory they are in. For links in the user’s home
1277 directory this will be @code{user_home_t}. But for links from the root
1278 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1279 directory, etc, this won’t work. @code{guix gc} would be prevented from
1280 reading and following these links.
1283 The daemon’s feature to listen for TCP connections might no longer work.
1284 This might require extra rules, because SELinux treats network sockets
1285 differently from files.
1288 Currently all files with a name matching the regular expression
1289 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1290 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1291 that name in any profile would be permitted to run in the
1292 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1293 build a package that provides this executable and convince a user to
1294 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1295 At that point SELinux could not prevent it from accessing files that are
1296 allowed for processes in that domain.
1298 We could generate a much more restrictive policy at installation time,
1299 so that only the @emph{exact} file name of the currently installed
1300 @code{guix-daemon} executable would be labelled with
1301 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1302 The downside is that root would have to install or upgrade the policy at
1303 installation time whenever the Guix package that provides the
1304 effectively running @code{guix-daemon} executable is upgraded.
1307 @node Invoking guix-daemon
1308 @section Invoking @command{guix-daemon}
1310 The @command{guix-daemon} program implements all the functionality to
1311 access the store. This includes launching build processes, running the
1312 garbage collector, querying the availability of a build result, etc. It
1313 is normally run as @code{root} like this:
1316 # guix-daemon --build-users-group=guixbuild
1320 For details on how to set it up, @pxref{Setting Up the Daemon}.
1323 @cindex container, build environment
1324 @cindex build environment
1325 @cindex reproducible builds
1326 By default, @command{guix-daemon} launches build processes under
1327 different UIDs, taken from the build group specified with
1328 @code{--build-users-group}. In addition, each build process is run in a
1329 chroot environment that only contains the subset of the store that the
1330 build process depends on, as specified by its derivation
1331 (@pxref{Programming Interface, derivation}), plus a set of specific
1332 system directories. By default, the latter contains @file{/dev} and
1333 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1334 @dfn{container}: in addition to having its own file system tree, it has
1335 a separate mount name space, its own PID name space, network name space,
1336 etc. This helps achieve reproducible builds (@pxref{Features}).
1338 When the daemon performs a build on behalf of the user, it creates a
1339 build directory under @file{/tmp} or under the directory specified by
1340 its @code{TMPDIR} environment variable. This directory is shared with
1341 the container for the duration of the build, though within the container,
1342 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1344 The build directory is automatically deleted upon completion, unless the
1345 build failed and the client specified @option{--keep-failed}
1346 (@pxref{Invoking guix build, @option{--keep-failed}}).
1348 The daemon listens for connections and spawns one sub-process for each session
1349 started by a client (one of the @command{guix} sub-commands.) The
1350 @command{guix processes} command allows you to get an overview of the activity
1351 on your system by viewing each of the active sessions and clients.
1352 @xref{Invoking guix processes}, for more information.
1354 The following command-line options are supported:
1357 @item --build-users-group=@var{group}
1358 Take users from @var{group} to run build processes (@pxref{Setting Up
1359 the Daemon, build users}).
1361 @item --no-substitutes
1363 Do not use substitutes for build products. That is, always build things
1364 locally instead of allowing downloads of pre-built binaries
1365 (@pxref{Substitutes}).
1367 When the daemon runs with @code{--no-substitutes}, clients can still
1368 explicitly enable substitution @i{via} the @code{set-build-options}
1369 remote procedure call (@pxref{The Store}).
1371 @item --substitute-urls=@var{urls}
1372 @anchor{daemon-substitute-urls}
1373 Consider @var{urls} the default whitespace-separated list of substitute
1374 source URLs. When this option is omitted,
1375 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1377 This means that substitutes may be downloaded from @var{urls}, as long
1378 as they are signed by a trusted signature (@pxref{Substitutes}).
1382 Do not use offload builds to other machines (@pxref{Daemon Offload
1383 Setup}). That is, always build things locally instead of offloading
1384 builds to remote machines.
1386 @item --cache-failures
1387 Cache build failures. By default, only successful builds are cached.
1389 When this option is used, @command{guix gc --list-failures} can be used
1390 to query the set of store items marked as failed; @command{guix gc
1391 --clear-failures} removes store items from the set of cached failures.
1392 @xref{Invoking guix gc}.
1394 @item --cores=@var{n}
1396 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1399 The default value is @code{0}, but it may be overridden by clients, such
1400 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1403 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1404 in the build process, which can then use it to exploit internal
1405 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1407 @item --max-jobs=@var{n}
1409 Allow at most @var{n} build jobs in parallel. The default value is
1410 @code{1}. Setting it to @code{0} means that no builds will be performed
1411 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1412 Setup}), or simply fail.
1414 @item --max-silent-time=@var{seconds}
1415 When the build or substitution process remains silent for more than
1416 @var{seconds}, terminate it and report a build failure.
1418 The default value is @code{0}, which disables the timeout.
1420 The value specified here can be overridden by clients (@pxref{Common
1421 Build Options, @code{--max-silent-time}}).
1423 @item --timeout=@var{seconds}
1424 Likewise, when the build or substitution process lasts for more than
1425 @var{seconds}, terminate it and report a build failure.
1427 The default value is @code{0}, which disables the timeout.
1429 The value specified here can be overridden by clients (@pxref{Common
1430 Build Options, @code{--timeout}}).
1432 @item --rounds=@var{N}
1433 Build each derivation @var{n} times in a row, and raise an error if
1434 consecutive build results are not bit-for-bit identical. Note that this
1435 setting can be overridden by clients such as @command{guix build}
1436 (@pxref{Invoking guix build}).
1438 When used in conjunction with @option{--keep-failed}, the differing
1439 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1440 This makes it easy to look for differences between the two results.
1443 Produce debugging output.
1445 This is useful to debug daemon start-up issues, but then it may be
1446 overridden by clients, for example the @code{--verbosity} option of
1447 @command{guix build} (@pxref{Invoking guix build}).
1449 @item --chroot-directory=@var{dir}
1450 Add @var{dir} to the build chroot.
1452 Doing this may change the result of build processes---for instance if
1453 they use optional dependencies found in @var{dir} when it is available,
1454 and not otherwise. For that reason, it is not recommended to do so.
1455 Instead, make sure that each derivation declares all the inputs that it
1458 @item --disable-chroot
1459 Disable chroot builds.
1461 Using this option is not recommended since, again, it would allow build
1462 processes to gain access to undeclared dependencies. It is necessary,
1463 though, when @command{guix-daemon} is running under an unprivileged user
1466 @item --log-compression=@var{type}
1467 Compress build logs according to @var{type}, one of @code{gzip},
1468 @code{bzip2}, or @code{none}.
1470 Unless @code{--lose-logs} is used, all the build logs are kept in the
1471 @var{localstatedir}. To save space, the daemon automatically compresses
1472 them with bzip2 by default.
1474 @item --disable-deduplication
1475 @cindex deduplication
1476 Disable automatic file ``deduplication'' in the store.
1478 By default, files added to the store are automatically ``deduplicated'':
1479 if a newly added file is identical to another one found in the store,
1480 the daemon makes the new file a hard link to the other file. This can
1481 noticeably reduce disk usage, at the expense of slightly increased
1482 input/output load at the end of a build process. This option disables
1485 @item --gc-keep-outputs[=yes|no]
1486 Tell whether the garbage collector (GC) must keep outputs of live
1490 @cindex garbage collector roots
1491 When set to ``yes'', the GC will keep the outputs of any live derivation
1492 available in the store---the @code{.drv} files. The default is ``no'',
1493 meaning that derivation outputs are kept only if they are reachable from a GC
1494 root. @xref{Invoking guix gc}, for more on GC roots.
1496 @item --gc-keep-derivations[=yes|no]
1497 Tell whether the garbage collector (GC) must keep derivations
1498 corresponding to live outputs.
1500 When set to ``yes'', as is the case by default, the GC keeps
1501 derivations---i.e., @code{.drv} files---as long as at least one of their
1502 outputs is live. This allows users to keep track of the origins of
1503 items in their store. Setting it to ``no'' saves a bit of disk space.
1505 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1506 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1507 ``yes'' causes liveness to flow from derivations to outputs. When both are
1508 set to ``yes'', the effect is to keep all the build prerequisites (the
1509 sources, compiler, libraries, and other build-time tools) of live objects in
1510 the store, regardless of whether these prerequisites are reachable from a GC
1511 root. This is convenient for developers since it saves rebuilds or downloads.
1513 @item --impersonate-linux-2.6
1514 On Linux-based systems, impersonate Linux 2.6. This means that the
1515 kernel's @code{uname} system call will report 2.6 as the release number.
1517 This might be helpful to build programs that (usually wrongfully) depend
1518 on the kernel version number.
1521 Do not keep build logs. By default they are kept under
1522 @code{@var{localstatedir}/guix/log}.
1524 @item --system=@var{system}
1525 Assume @var{system} as the current system type. By default it is the
1526 architecture/kernel pair found at configure time, such as
1527 @code{x86_64-linux}.
1529 @item --listen=@var{endpoint}
1530 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1531 as the file name of a Unix-domain socket if it starts with
1532 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1533 host name or host name and port to listen to. Here are a few examples:
1536 @item --listen=/gnu/var/daemon
1537 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1538 creating it if needed.
1540 @item --listen=localhost
1541 @cindex daemon, remote access
1542 @cindex remote access to the daemon
1543 @cindex daemon, cluster setup
1544 @cindex clusters, daemon setup
1545 Listen for TCP connections on the network interface corresponding to
1546 @code{localhost}, on port 44146.
1548 @item --listen=128.0.0.42:1234
1549 Listen for TCP connections on the network interface corresponding to
1550 @code{128.0.0.42}, on port 1234.
1553 This option can be repeated multiple times, in which case
1554 @command{guix-daemon} accepts connections on all the specified
1555 endpoints. Users can tell client commands what endpoint to connect to
1556 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1557 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1560 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1561 @code{--listen=@var{host}} is suitable on local networks, such as
1562 clusters, where only trusted nodes may connect to the build daemon. In
1563 other cases where remote access to the daemon is needed, we recommend
1564 using Unix-domain sockets along with SSH.
1567 When @code{--listen} is omitted, @command{guix-daemon} listens for
1568 connections on the Unix-domain socket located at
1569 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1573 @node Application Setup
1574 @section Application Setup
1576 @cindex foreign distro
1577 When using Guix on top of GNU/Linux distribution other than Guix System---a
1578 so-called @dfn{foreign distro}---a few additional steps are needed to
1579 get everything in place. Here are some of them.
1583 @anchor{locales-and-locpath}
1584 @cindex locales, when not on Guix System
1586 @vindex GUIX_LOCPATH
1587 Packages installed @i{via} Guix will not use the locale data of the
1588 host system. Instead, you must first install one of the locale packages
1589 available with Guix and then define the @code{GUIX_LOCPATH} environment
1593 $ guix install glibc-locales
1594 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1597 Note that the @code{glibc-locales} package contains data for all the
1598 locales supported by the GNU@tie{}libc and weighs in at around
1599 110@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1600 limited to a few UTF-8 locales.
1602 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1603 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1604 Manual}). There are two important differences though:
1608 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1609 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1610 to make sure the programs of the foreign distro will not end up loading
1611 incompatible locale data.
1614 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1615 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1616 should your Guix profile contain a mixture of programs linked against
1617 different libc version, each libc version will only try to load locale
1618 data in the right format.
1621 This is important because the locale data format used by different libc
1622 versions may be incompatible.
1624 @subsection Name Service Switch
1626 @cindex name service switch, glibc
1627 @cindex NSS (name service switch), glibc
1628 @cindex nscd (name service caching daemon)
1629 @cindex name service caching daemon (nscd)
1630 When using Guix on a foreign distro, we @emph{strongly recommend} that
1631 the system run the GNU C library's @dfn{name service cache daemon},
1632 @command{nscd}, which should be listening on the
1633 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1634 installed with Guix may fail to look up host names or user accounts, or
1635 may even crash. The next paragraphs explain why.
1637 @cindex @file{nsswitch.conf}
1638 The GNU C library implements a @dfn{name service switch} (NSS), which is
1639 an extensible mechanism for ``name lookups'' in general: host name
1640 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1641 The GNU C Library Reference Manual}).
1643 @cindex Network information service (NIS)
1644 @cindex NIS (Network information service)
1645 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1646 lookup implementations: for example, the @code{nss-mdns} plugin allow
1647 resolution of @code{.local} host names, the @code{nis} plugin allows
1648 user account lookup using the Network information service (NIS), and so
1649 on. These extra ``lookup services'' are configured system-wide in
1650 @file{/etc/nsswitch.conf}, and all the programs running on the system
1651 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1654 When they perform a name lookup---for instance by calling the
1655 @code{getaddrinfo} function in C---applications first try to connect to
1656 the nscd; on success, nscd performs name lookups on their behalf. If
1657 the nscd is not running, then they perform the name lookup by
1658 themselves, by loading the name lookup services into their own address
1659 space and running it. These name lookup services---the
1660 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1661 the host system's C library, rather than from the C library the
1662 application is linked against (the C library coming from Guix).
1664 And this is where the problem is: if your application is linked against
1665 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1666 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1667 likely crash or have its name lookups fail unexpectedly.
1669 Running @command{nscd} on the system, among other advantages, eliminates
1670 this binary incompatibility problem because those @code{libnss_*.so}
1671 files are loaded in the @command{nscd} process, not in applications
1674 @subsection X11 Fonts
1677 The majority of graphical applications use Fontconfig to locate and
1678 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1679 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1680 by default. Thus, to allow graphical applications installed with Guix
1681 to display fonts, you have to install fonts with Guix as well.
1682 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1683 @code{font-gnu-freefont-ttf}.
1685 To display text written in Chinese languages, Japanese, or Korean in
1686 graphical applications, consider installing
1687 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1688 has multiple outputs, one per language family (@pxref{Packages with
1689 Multiple Outputs}). For instance, the following command installs fonts
1690 for Chinese languages:
1693 guix install font-adobe-source-han-sans:cn
1696 @cindex @code{xterm}
1697 Older programs such as @command{xterm} do not use Fontconfig and instead
1698 rely on server-side font rendering. Such programs require to specify a
1699 full name of a font using XLFD (X Logical Font Description), like this:
1702 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1705 To be able to use such full names for the TrueType fonts installed in
1706 your Guix profile, you need to extend the font path of the X server:
1708 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1709 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1711 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1714 @cindex @code{xlsfonts}
1715 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1716 to make sure your TrueType fonts are listed there.
1718 @cindex @code{fc-cache}
1720 After installing fonts you may have to refresh the font cache to use
1721 them in applications. The same applies when applications installed via
1722 Guix do not seem to find fonts. To force rebuilding of the font cache
1723 run @code{fc-cache -rv}. The @code{fc-cache} command is provided by
1724 the @code{fontconfig} package.
1726 @subsection X.509 Certificates
1728 @cindex @code{nss-certs}
1729 The @code{nss-certs} package provides X.509 certificates, which allow
1730 programs to authenticate Web servers accessed over HTTPS.
1732 When using Guix on a foreign distro, you can install this package and
1733 define the relevant environment variables so that packages know where to
1734 look for certificates. @xref{X.509 Certificates}, for detailed
1737 @subsection Emacs Packages
1739 @cindex @code{emacs}
1740 When you install Emacs packages with Guix, the elisp files may be placed
1741 either in @file{$HOME/.guix-profile/share/emacs/site-lisp/} or in
1743 @file{$HOME/.guix-profile/share/emacs/site-lisp/guix.d/}. The latter
1744 directory exists because potentially there may exist thousands of Emacs
1745 packages and storing all their files in a single directory may not be
1746 reliable (because of name conflicts). So we think using a separate
1747 directory for each package is a good idea. It is very similar to how
1748 the Emacs package system organizes the file structure (@pxref{Package
1749 Files,,, emacs, The GNU Emacs Manual}).
1751 By default, Emacs (installed with Guix) ``knows'' where these packages
1752 are placed, so you do not need to perform any configuration. If, for
1753 some reason, you want to avoid auto-loading Emacs packages installed
1754 with Guix, you can do so by running Emacs with @code{--no-site-file}
1755 option (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1757 @subsection The GCC toolchain
1762 Guix offers individual compiler packages such as @code{gcc} but if you
1763 are in need of a complete toolchain for compiling and linking source
1764 code what you really want is the @code{gcc-toolchain} package. This
1765 package provides a complete GCC toolchain for C/C++ development,
1766 including GCC itself, the GNU C Library (headers and binaries, plus
1767 debugging symbols in the @code{debug} output), Binutils, and a linker
1770 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
1771 passed to the linker, add corresponding @code{-rpath} arguments, and
1772 invoke the actual linker with this new set of arguments. You can instruct the
1773 wrapper to refuse to link against libraries not in the store by setting the
1774 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
1776 @node Upgrading Guix
1777 @section Upgrading Guix
1779 @cindex Upgrading Guix, on a foreign distro
1781 To upgrade Guix, run:
1787 @xref{Invoking guix pull}, for more information.
1789 @cindex upgrading Guix for the root user, on a foreign distro
1790 @cindex upgrading the Guix daemon, on a foreign distro
1791 @cindex @command{guix pull} for the root user, on a foreign distro
1793 On a foreign distro, you can upgrade the build daemon by running:
1800 followed by (assuming your distro uses the systemd service management
1804 systemctl restart guix-daemon.service
1807 On Guix System, upgrading the daemon is achieved by reconfiguring the
1808 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1812 @c *********************************************************************
1813 @node System Installation
1814 @chapter System Installation
1816 @cindex installing Guix System
1817 @cindex Guix System, installation
1818 This section explains how to install Guix System
1819 on a machine. Guix, as a package manager, can
1820 also be installed on top of a running GNU/Linux system,
1821 @pxref{Installation}.
1825 @c This paragraph is for people reading this from tty2 of the
1826 @c installation image.
1827 You are reading this documentation with an Info reader. For details on
1828 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1829 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1830 Info}. Hit @kbd{l} afterwards to come back here.
1832 Alternately, run @command{info info} in another tty to keep the manual
1838 * Limitations:: What you can expect.
1839 * Hardware Considerations:: Supported hardware.
1840 * USB Stick and DVD Installation:: Preparing the installation medium.
1841 * Preparing for Installation:: Networking, partitioning, etc.
1842 * Guided Graphical Installation:: Easy graphical installation.
1843 * Manual Installation:: Manual installation for wizards.
1844 * After System Installation:: When installation succeeded.
1845 * Installing Guix in a VM:: Guix System playground.
1846 * Building the Installation Image:: How this comes to be.
1850 @section Limitations
1852 We consider Guix System to be ready for a wide range of ``desktop'' and server
1853 use cases. The reliability guarantees it provides---transactional upgrades
1854 and rollbacks, reproducibility---make it a solid foundation.
1856 Nevertheless, before you proceed with the installation, be aware of the
1857 following noteworthy limitations applicable to version @value{VERSION}:
1861 Support for the Logical Volume Manager (LVM) is missing.
1864 More and more system services are provided (@pxref{Services}), but some
1868 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1869 as well as a number of X11 window managers. However, KDE is currently
1873 More than a disclaimer, this is an invitation to report issues (and success
1874 stories!), and to join us in improving it. @xref{Contributing}, for more
1878 @node Hardware Considerations
1879 @section Hardware Considerations
1881 @cindex hardware support on Guix System
1882 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1883 builds around the kernel Linux-libre, which means that only hardware for
1884 which free software drivers and firmware exist is supported. Nowadays,
1885 a wide range of off-the-shelf hardware is supported on
1886 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1887 Ethernet controllers. Unfortunately, there are still areas where
1888 hardware vendors deny users control over their own computing, and such
1889 hardware is not supported on Guix System.
1891 @cindex WiFi, hardware support
1892 One of the main areas where free drivers or firmware are lacking is WiFi
1893 devices. WiFi devices known to work include those using Atheros chips
1894 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1895 driver, and those using Broadcom/AirForce chips (BCM43xx with
1896 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1897 Linux-libre driver. Free firmware exists for both and is available
1898 out-of-the-box on Guix System, as part of @code{%base-firmware}
1899 (@pxref{operating-system Reference, @code{firmware}}).
1901 @cindex RYF, Respects Your Freedom
1902 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1903 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1904 certification program for hardware products that respect your freedom
1905 and your privacy and ensure that you have control over your device. We
1906 encourage you to check the list of RYF-certified devices.
1908 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1909 web site. It contains a catalog of hardware devices with information
1910 about their support in GNU/Linux.
1913 @node USB Stick and DVD Installation
1914 @section USB Stick and DVD Installation
1916 An ISO-9660 installation image that can be written to a USB stick or
1917 burnt to a DVD can be downloaded from
1918 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1919 where @var{system} is one of:
1923 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1926 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1929 @c start duplication of authentication part from ``Binary Installation''
1930 Make sure to download the associated @file{.sig} file and to verify the
1931 authenticity of the image against it, along these lines:
1934 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1935 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1938 If that command fails because you do not have the required public key,
1939 then run this command to import it:
1942 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1943 -qO - | gpg --import -
1947 and rerun the @code{gpg --verify} command.
1949 Take note that a warning like ``This key is not certified with a trusted
1950 signature!'' is normal.
1954 This image contains the tools necessary for an installation.
1955 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1957 @unnumberedsubsec Copying to a USB Stick
1959 To copy the image to a USB stick, follow these steps:
1963 Decompress the image using the @command{xz} command:
1966 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1970 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1971 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1972 copy the image with:
1975 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1979 Access to @file{/dev/sdX} usually requires root privileges.
1982 @unnumberedsubsec Burning on a DVD
1984 To copy the image to a DVD, follow these steps:
1988 Decompress the image using the @command{xz} command:
1991 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1995 Insert a blank DVD into your machine, and determine
1996 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
1997 copy the image with:
2000 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
2003 Access to @file{/dev/srX} usually requires root privileges.
2006 @unnumberedsubsec Booting
2008 Once this is done, you should be able to reboot the system and boot from
2009 the USB stick or DVD. The latter usually requires you to get in the
2010 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2011 In order to boot from Libreboot, switch to the command mode by pressing
2012 the @kbd{c} key and type @command{search_grub usb}.
2014 @xref{Installing Guix in a VM}, if, instead, you would like to install
2015 Guix System in a virtual machine (VM).
2018 @node Preparing for Installation
2019 @section Preparing for Installation
2021 Once you have booted, you can use the guided graphical installer, which makes
2022 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
2023 if you are already familiar with GNU/Linux and if you want more control than
2024 what the graphical installer provides, you can choose the ``manual''
2025 installation process (@pxref{Manual Installation}).
2027 The graphical installer is available on TTY1. You can obtain root shells on
2028 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2029 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2030 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2031 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2032 which allows you to select text with the left mouse button and to paste it
2033 with the middle button.
2036 Installation requires access to the Internet so that any missing
2037 dependencies of your system configuration can be downloaded. See the
2038 ``Networking'' section below.
2041 @node Guided Graphical Installation
2042 @section Guided Graphical Installation
2044 The graphical installer is a text-based user interface. It will guide you,
2045 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2047 The first dialog boxes allow you to set up the system as you use it during the
2048 installation: you can choose the language, keyboard layout, and set up
2049 networking, which will be used during the installation. The image below shows
2050 the networking dialog.
2052 @image{images/installer-network,5in,, networking setup with the graphical installer}
2054 Later steps allow you to partition your hard disk, as shown in the image
2055 below, to choose whether or not to use encrypted file systems, to enter the
2056 host name and root password, and to create an additional account, among other
2059 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2061 Note that, at any time, the installer allows you to exit the current
2062 installation step and resume at a previous step, as show in the image below.
2064 @image{images/installer-resume,5in,, resuming the installation process}
2066 Once you're done, the installer produces an operating system configuration and
2067 displays it (@pxref{Using the Configuration System}). At that point you can
2068 hit ``OK'' and installation will proceed. On success, you can reboot into the
2069 new system and enjoy. @xref{After System Installation}, for what's next!
2072 @node Manual Installation
2073 @section Manual Installation
2075 This section describes how you would ``manually'' install GNU@tie{}Guix System
2076 on your machine. This option requires familiarity with GNU/Linux, with the
2077 shell, and with common administration tools. If you think this is not for
2078 you, consider using the guided graphical installer (@pxref{Guided Graphical
2081 The installation system provides root shells on TTYs 3 to 6; press
2082 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2083 many common tools needed to install the system. But it is also a full-blown
2084 Guix System, which means that you can install additional packages, should you
2085 need it, using @command{guix package} (@pxref{Invoking guix package}).
2088 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2089 * Proceeding with the Installation:: Installing.
2092 @node Keyboard Layout and Networking and Partitioning
2093 @subsection Keyboard Layout, Networking, and Partitioning
2095 Before you can install the system, you may want to adjust the keyboard layout,
2096 set up networking, and partition your target hard disk. This section will
2097 guide you through this.
2099 @subsubsection Keyboard Layout
2101 @cindex keyboard layout
2102 The installation image uses the US qwerty keyboard layout. If you want
2103 to change it, you can use the @command{loadkeys} command. For example,
2104 the following command selects the Dvorak keyboard layout:
2110 See the files under @file{/run/current-system/profile/share/keymaps} for
2111 a list of available keyboard layouts. Run @command{man loadkeys} for
2114 @subsubsection Networking
2116 Run the following command to see what your network interfaces are called:
2123 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2129 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2130 Wired interfaces have a name starting with @samp{e}; for example, the
2131 interface corresponding to the first on-board Ethernet controller is
2132 called @samp{eno1}. Wireless interfaces have a name starting with
2133 @samp{w}, like @samp{w1p2s0}.
2136 @item Wired connection
2137 To configure a wired network run the following command, substituting
2138 @var{interface} with the name of the wired interface you want to use.
2141 ifconfig @var{interface} up
2145 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2148 ip link set @var{interface} up
2151 @item Wireless connection
2154 To configure wireless networking, you can create a configuration file
2155 for the @command{wpa_supplicant} configuration tool (its location is not
2156 important) using one of the available text editors such as
2160 nano wpa_supplicant.conf
2163 As an example, the following stanza can go to this file and will work
2164 for many wireless networks, provided you give the actual SSID and
2165 passphrase for the network you are connecting to:
2169 ssid="@var{my-ssid}"
2171 psk="the network's secret passphrase"
2175 Start the wireless service and run it in the background with the
2176 following command (substitute @var{interface} with the name of the
2177 network interface you want to use):
2180 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2183 Run @command{man wpa_supplicant} for more information.
2187 At this point, you need to acquire an IP address. On a network where IP
2188 addresses are automatically assigned @i{via} DHCP, you can run:
2191 dhclient -v @var{interface}
2194 Try to ping a server to see if networking is up and running:
2200 Setting up network access is almost always a requirement because the
2201 image does not contain all the software and tools that may be needed.
2203 @cindex installing over SSH
2204 If you want to, you can continue the installation remotely by starting
2208 herd start ssh-daemon
2211 Make sure to either set a password with @command{passwd}, or configure
2212 OpenSSH public key authentication before logging in.
2214 @subsubsection Disk Partitioning
2216 Unless this has already been done, the next step is to partition, and
2217 then format the target partition(s).
2219 The installation image includes several partitioning tools, including
2220 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2221 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2222 the partition layout you want:
2228 If your disk uses the GUID Partition Table (GPT) format and you plan to
2229 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2230 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2233 @cindex EFI, installation
2234 @cindex UEFI, installation
2235 @cindex ESP, EFI system partition
2236 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2237 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2238 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2241 parted /dev/sda set 1 esp on
2245 @vindex grub-bootloader
2246 @vindex grub-efi-bootloader
2247 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2248 @file{/sys/firmware/efi} exists in the installation image, then you should
2249 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2250 Otherwise you should use the BIOS-based GRUB, known as
2251 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2255 Once you are done partitioning the target hard disk drive, you have to
2256 create a file system on the relevant partition(s)@footnote{Currently
2257 Guix System only supports ext4, btrfs, and JFS file systems. In particular,
2258 code that reads file system UUIDs and labels only works for these file system
2259 types.}. For the ESP, if you have one and assuming it is
2260 @file{/dev/sda1}, run:
2263 mkfs.fat -F32 /dev/sda1
2266 Preferably, assign file systems a label so that you can easily and
2267 reliably refer to them in @code{file-system} declarations (@pxref{File
2268 Systems}). This is typically done using the @code{-L} option of
2269 @command{mkfs.ext4} and related commands. So, assuming the target root
2270 partition lives at @file{/dev/sda2}, a file system with the label
2271 @code{my-root} can be created with:
2274 mkfs.ext4 -L my-root /dev/sda2
2277 @cindex encrypted disk
2278 If you are instead planning to encrypt the root partition, you can use
2279 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2280 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2281 @code{man cryptsetup}} for more information.) Assuming you want to
2282 store the root partition on @file{/dev/sda2}, the command sequence would
2283 be along these lines:
2286 cryptsetup luksFormat /dev/sda2
2287 cryptsetup open --type luks /dev/sda2 my-partition
2288 mkfs.ext4 -L my-root /dev/mapper/my-partition
2291 Once that is done, mount the target file system under @file{/mnt}
2292 with a command like (again, assuming @code{my-root} is the label of the
2296 mount LABEL=my-root /mnt
2299 Also mount any other file systems you would like to use on the target
2300 system relative to this path. If you have opted for @file{/boot/efi} as an
2301 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2302 found by @code{guix system init} afterwards.
2304 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2305 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2306 sure to initialize them with @command{mkswap}. Assuming you have one
2307 swap partition on @file{/dev/sda3}, you would run:
2314 Alternatively, you may use a swap file. For example, assuming that in
2315 the new system you want to use the file @file{/swapfile} as a swap file,
2316 you would run@footnote{This example will work for many types of file
2317 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2318 btrfs), the required steps may be different. For details, see the
2319 manual pages for @command{mkswap} and @command{swapon}.}:
2322 # This is 10 GiB of swap space. Adjust "count" to change the size.
2323 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2324 # For security, make the file readable and writable only by root.
2325 chmod 600 /mnt/swapfile
2326 mkswap /mnt/swapfile
2327 swapon /mnt/swapfile
2330 Note that if you have encrypted the root partition and created a swap
2331 file in its file system as described above, then the encryption also
2332 protects the swap file, just like any other file in that file system.
2334 @node Proceeding with the Installation
2335 @subsection Proceeding with the Installation
2337 With the target partitions ready and the target root mounted on
2338 @file{/mnt}, we're ready to go. First, run:
2341 herd start cow-store /mnt
2344 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2345 during the installation phase are written to the target disk on @file{/mnt}
2346 rather than kept in memory. This is necessary because the first phase of
2347 the @command{guix system init} command (see below) entails downloads or
2348 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2350 Next, you have to edit a file and
2351 provide the declaration of the operating system to be installed. To
2352 that end, the installation system comes with three text editors. We
2353 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2354 supports syntax highlighting and parentheses matching; other editors
2355 include GNU Zile (an Emacs clone), and
2356 nvi (a clone of the original BSD @command{vi} editor).
2357 We strongly recommend storing that file on the target root file system, say,
2358 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2359 configuration file once you have rebooted into the newly-installed system.
2361 @xref{Using the Configuration System}, for an overview of the
2362 configuration file. The example configurations discussed in that
2363 section are available under @file{/etc/configuration} in the
2364 installation image. Thus, to get started with a system configuration
2365 providing a graphical display server (a ``desktop'' system), you can run
2366 something along these lines:
2370 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2371 # nano /mnt/etc/config.scm
2374 You should pay attention to what your configuration file contains, and
2379 Make sure the @code{bootloader-configuration} form refers to the target
2380 you want to install GRUB on. It should mention @code{grub-bootloader} if
2381 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2382 for newer UEFI systems. For legacy systems, the @code{target} field
2383 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2384 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2385 currently mounted and a @code{file-system} entry is specified in your
2389 Be sure that your file system labels match the value of their respective
2390 @code{device} fields in your @code{file-system} configuration, assuming
2391 your @code{file-system} configuration uses the @code{file-system-label}
2392 procedure in its @code{device} field.
2395 If there are encrypted or RAID partitions, make sure to add a
2396 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2399 Once you are done preparing the configuration file, the new system must
2400 be initialized (remember that the target root file system is mounted
2404 guix system init /mnt/etc/config.scm /mnt
2408 This copies all the necessary files and installs GRUB on
2409 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2410 more information, @pxref{Invoking guix system}. This command may trigger
2411 downloads or builds of missing packages, which can take some time.
2413 Once that command has completed---and hopefully succeeded!---you can run
2414 @command{reboot} and boot into the new system. The @code{root} password
2415 in the new system is initially empty; other users' passwords need to be
2416 initialized by running the @command{passwd} command as @code{root},
2417 unless your configuration specifies otherwise
2418 (@pxref{user-account-password, user account passwords}).
2419 @xref{After System Installation}, for what's next!
2422 @node After System Installation
2423 @section After System Installation
2425 Success, you've now booted into Guix System! From then on, you can update the
2426 system whenever you want by running, say:
2430 sudo guix system reconfigure /etc/config.scm
2434 This builds a new system generation with the latest packages and services
2435 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2436 your system includes the latest security updates (@pxref{Security Updates}).
2438 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2440 @cindex sudo vs. @command{guix pull}
2441 Note that @command{sudo guix} runs your user's @command{guix} command and
2442 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2443 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2445 The difference matters here, because @command{guix pull} updates
2446 the @command{guix} command and package definitions only for the user it is ran
2447 as. This means that if you choose to use @command{guix system reconfigure} in
2448 root's login shell, you'll need to @command{guix pull} separately.
2451 Join us on @code{#guix} on the Freenode IRC network or on
2452 @email{guix-devel@@gnu.org} to share your experience!
2455 @node Installing Guix in a VM
2456 @section Installing Guix in a Virtual Machine
2458 @cindex virtual machine, Guix System installation
2459 @cindex virtual private server (VPS)
2460 @cindex VPS (virtual private server)
2461 If you'd like to install Guix System in a virtual machine (VM) or on a
2462 virtual private server (VPS) rather than on your beloved machine, this
2465 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2466 disk image, follow these steps:
2470 First, retrieve and decompress the Guix system installation image as
2471 described previously (@pxref{USB Stick and DVD Installation}).
2474 Create a disk image that will hold the installed system. To make a
2475 qcow2-formatted disk image, use the @command{qemu-img} command:
2478 qemu-img create -f qcow2 guix-system.img 50G
2481 The resulting file will be much smaller than 50 GB (typically less than
2482 1 MB), but it will grow as the virtualized storage device is filled up.
2485 Boot the USB installation image in an VM:
2488 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2489 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2490 -drive file=guix-system.img \
2491 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2494 @code{-enable-kvm} is optional, but significantly improves performance,
2495 @pxref{Running Guix in a VM}.
2498 You're now root in the VM, proceed with the installation process.
2499 @xref{Preparing for Installation}, and follow the instructions.
2502 Once installation is complete, you can boot the system that's on your
2503 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2506 @node Building the Installation Image
2507 @section Building the Installation Image
2509 @cindex installation image
2510 The installation image described above was built using the @command{guix
2511 system} command, specifically:
2514 guix system disk-image --file-system-type=iso9660 \
2515 gnu/system/install.scm
2518 Have a look at @file{gnu/system/install.scm} in the source tree,
2519 and see also @ref{Invoking guix system} for more information
2520 about the installation image.
2522 @section Building the Installation Image for ARM Boards
2524 Many ARM boards require a specific variant of the
2525 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2527 If you build a disk image and the bootloader is not available otherwise
2528 (on another boot drive etc), it's advisable to build an image that
2529 includes the bootloader, specifically:
2532 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2535 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2536 board, a list of possible boards will be printed.
2538 @c *********************************************************************
2539 @node Package Management
2540 @chapter Package Management
2543 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2544 remove software packages, without having to know about their build
2545 procedures or dependencies. Guix also goes beyond this obvious set of
2548 This chapter describes the main features of Guix, as well as the
2549 package management tools it provides. Along with the command-line
2550 interface described below (@pxref{Invoking guix package, @code{guix
2551 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2552 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2553 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2557 guix install emacs-guix
2561 * Features:: How Guix will make your life brighter.
2562 * Invoking guix package:: Package installation, removal, etc.
2563 * Substitutes:: Downloading pre-built binaries.
2564 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2565 * Invoking guix gc:: Running the garbage collector.
2566 * Invoking guix pull:: Fetching the latest Guix and distribution.
2567 * Channels:: Customizing the package collection.
2568 * Invoking guix time-machine:: Running an older revision of Guix.
2569 * Inferiors:: Interacting with another revision of Guix.
2570 * Invoking guix describe:: Display information about your Guix revision.
2571 * Invoking guix archive:: Exporting and importing store files.
2577 When using Guix, each package ends up in the @dfn{package store}, in its
2578 own directory---something that resembles
2579 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2581 Instead of referring to these directories, users have their own
2582 @dfn{profile}, which points to the packages that they actually want to
2583 use. These profiles are stored within each user's home directory, at
2584 @code{$HOME/.guix-profile}.
2586 For example, @code{alice} installs GCC 4.7.2. As a result,
2587 @file{/home/alice/.guix-profile/bin/gcc} points to
2588 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2589 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2590 simply continues to point to
2591 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2592 coexist on the same system without any interference.
2594 The @command{guix package} command is the central tool to manage
2595 packages (@pxref{Invoking guix package}). It operates on the per-user
2596 profiles, and can be used @emph{with normal user privileges}.
2598 @cindex transactions
2599 The command provides the obvious install, remove, and upgrade
2600 operations. Each invocation is actually a @emph{transaction}: either
2601 the specified operation succeeds, or nothing happens. Thus, if the
2602 @command{guix package} process is terminated during the transaction,
2603 or if a power outage occurs during the transaction, then the user's
2604 profile remains in its previous state, and remains usable.
2606 In addition, any package transaction may be @emph{rolled back}. So, if,
2607 for example, an upgrade installs a new version of a package that turns
2608 out to have a serious bug, users may roll back to the previous instance
2609 of their profile, which was known to work well. Similarly, the global
2610 system configuration on Guix is subject to
2611 transactional upgrades and roll-back
2612 (@pxref{Using the Configuration System}).
2614 All packages in the package store may be @emph{garbage-collected}.
2615 Guix can determine which packages are still referenced by user
2616 profiles, and remove those that are provably no longer referenced
2617 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2618 generations of their profile so that the packages they refer to can be
2621 @cindex reproducibility
2622 @cindex reproducible builds
2623 Guix takes a @dfn{purely functional} approach to package
2624 management, as described in the introduction (@pxref{Introduction}).
2625 Each @file{/gnu/store} package directory name contains a hash of all the
2626 inputs that were used to build that package---compiler, libraries, build
2627 scripts, etc. This direct correspondence allows users to make sure a
2628 given package installation matches the current state of their
2629 distribution. It also helps maximize @dfn{build reproducibility}:
2630 thanks to the isolated build environments that are used, a given build
2631 is likely to yield bit-identical files when performed on different
2632 machines (@pxref{Invoking guix-daemon, container}).
2635 This foundation allows Guix to support @dfn{transparent binary/source
2636 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2637 available from an external source---a @dfn{substitute}, Guix just
2638 downloads it and unpacks it;
2639 otherwise, it builds the package from source, locally
2640 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2641 reproducible, users do not have to trust servers that provide
2642 substitutes: they can force a local build and @emph{challenge} providers
2643 (@pxref{Invoking guix challenge}).
2645 Control over the build environment is a feature that is also useful for
2646 developers. The @command{guix environment} command allows developers of
2647 a package to quickly set up the right development environment for their
2648 package, without having to manually install the dependencies of the
2649 package into their profile (@pxref{Invoking guix environment}).
2651 @cindex replication, of software environments
2652 @cindex provenance tracking, of software artifacts
2653 All of Guix and its package definitions is version-controlled, and
2654 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2655 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2656 Guix instance on a different machine or at a later point in time, which in
2657 turn allows you to @emph{replicate complete software environments}, while
2658 retaining precise @dfn{provenance tracking} of the software.
2660 @node Invoking guix package
2661 @section Invoking @command{guix package}
2663 @cindex installing packages
2664 @cindex removing packages
2665 @cindex package installation
2666 @cindex package removal
2667 The @command{guix package} command is the tool that allows users to
2668 install, upgrade, and remove packages, as well as rolling back to
2669 previous configurations. It operates only on the user's own profile,
2670 and works with normal user privileges (@pxref{Features}). Its syntax
2674 guix package @var{options}
2677 @cindex transactions
2678 Primarily, @var{options} specifies the operations to be performed during
2679 the transaction. Upon completion, a new profile is created, but
2680 previous @dfn{generations} of the profile remain available, should the user
2683 For example, to remove @code{lua} and install @code{guile} and
2684 @code{guile-cairo} in a single transaction:
2687 guix package -r lua -i guile guile-cairo
2690 @cindex aliases, for @command{guix package}
2691 For your convenience, we also provide the following aliases:
2695 @command{guix search} is an alias for @command{guix package -s},
2697 @command{guix install} is an alias for @command{guix package -i},
2699 @command{guix remove} is an alias for @command{guix package -r},
2701 @command{guix upgrade} is an alias for @command{guix package -u},
2703 and @command{guix show} is an alias for @command{guix package --show=}.
2706 These aliases are less expressive than @command{guix package} and provide
2707 fewer options, so in some cases you'll probably want to use @command{guix
2710 @command{guix package} also supports a @dfn{declarative approach}
2711 whereby the user specifies the exact set of packages to be available and
2712 passes it @i{via} the @option{--manifest} option
2713 (@pxref{profile-manifest, @option{--manifest}}).
2716 For each user, a symlink to the user's default profile is automatically
2717 created in @file{$HOME/.guix-profile}. This symlink always points to the
2718 current generation of the user's default profile. Thus, users can add
2719 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2720 variable, and so on.
2721 @cindex search paths
2722 If you are not using Guix System, consider adding the
2723 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2724 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2725 shells get all the right environment variable definitions:
2728 GUIX_PROFILE="$HOME/.guix-profile" ; \
2729 source "$HOME/.guix-profile/etc/profile"
2732 In a multi-user setup, user profiles are stored in a place registered as
2733 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2734 to (@pxref{Invoking guix gc}). That directory is normally
2735 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2736 @var{localstatedir} is the value passed to @code{configure} as
2737 @code{--localstatedir}, and @var{user} is the user name. The
2738 @file{per-user} directory is created when @command{guix-daemon} is
2739 started, and the @var{user} sub-directory is created by @command{guix
2742 The @var{options} can be among the following:
2746 @item --install=@var{package} @dots{}
2747 @itemx -i @var{package} @dots{}
2748 Install the specified @var{package}s.
2750 Each @var{package} may specify either a simple package name, such as
2751 @code{guile}, or a package name followed by an at-sign and version number,
2752 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2753 case, the newest version prefixed by @code{1.8} is selected.)
2755 If no version number is specified, the
2756 newest available version will be selected. In addition, @var{package}
2757 may contain a colon, followed by the name of one of the outputs of the
2758 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2759 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2760 name (and optionally version) are searched for among the GNU
2761 distribution modules (@pxref{Package Modules}).
2763 @cindex propagated inputs
2764 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2765 that automatically get installed along with the required package
2766 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2767 @code{package} objects}, for information about propagated inputs in
2768 package definitions).
2770 @anchor{package-cmd-propagated-inputs}
2771 An example is the GNU MPC library: its C header files refer to those of
2772 the GNU MPFR library, which in turn refer to those of the GMP library.
2773 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2774 in the profile; removing MPC also removes MPFR and GMP---unless they had
2775 also been explicitly installed by the user.
2777 Besides, packages sometimes rely on the definition of environment
2778 variables for their search paths (see explanation of
2779 @code{--search-paths} below). Any missing or possibly incorrect
2780 environment variable definitions are reported here.
2782 @item --install-from-expression=@var{exp}
2784 Install the package @var{exp} evaluates to.
2786 @var{exp} must be a Scheme expression that evaluates to a
2787 @code{<package>} object. This option is notably useful to disambiguate
2788 between same-named variants of a package, with expressions such as
2789 @code{(@@ (gnu packages base) guile-final)}.
2791 Note that this option installs the first output of the specified
2792 package, which may be insufficient when needing a specific output of a
2793 multiple-output package.
2795 @item --install-from-file=@var{file}
2796 @itemx -f @var{file}
2797 Install the package that the code within @var{file} evaluates to.
2799 As an example, @var{file} might contain a definition like this
2800 (@pxref{Defining Packages}):
2803 @include package-hello.scm
2806 Developers may find it useful to include such a @file{guix.scm} file
2807 in the root of their project source tree that can be used to test
2808 development snapshots and create reproducible development environments
2809 (@pxref{Invoking guix environment}).
2811 @item --remove=@var{package} @dots{}
2812 @itemx -r @var{package} @dots{}
2813 Remove the specified @var{package}s.
2815 As for @code{--install}, each @var{package} may specify a version number
2816 and/or output name in addition to the package name. For instance,
2817 @code{-r glibc:debug} would remove the @code{debug} output of
2820 @item --upgrade[=@var{regexp} @dots{}]
2821 @itemx -u [@var{regexp} @dots{}]
2822 @cindex upgrading packages
2823 Upgrade all the installed packages. If one or more @var{regexp}s are
2824 specified, upgrade only installed packages whose name matches a
2825 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2827 Note that this upgrades package to the latest version of packages found
2828 in the distribution currently installed. To update your distribution,
2829 you should regularly run @command{guix pull} (@pxref{Invoking guix
2832 @item --do-not-upgrade[=@var{regexp} @dots{}]
2833 When used together with the @code{--upgrade} option, do @emph{not}
2834 upgrade any packages whose name matches a @var{regexp}. For example, to
2835 upgrade all packages in the current profile except those containing the
2836 substring ``emacs'':
2839 $ guix package --upgrade . --do-not-upgrade emacs
2842 @item @anchor{profile-manifest}--manifest=@var{file}
2843 @itemx -m @var{file}
2844 @cindex profile declaration
2845 @cindex profile manifest
2846 Create a new generation of the profile from the manifest object
2847 returned by the Scheme code in @var{file}. This option can be repeated
2848 several times, in which case the manifests are concatenated.
2850 This allows you to @emph{declare} the profile's contents rather than
2851 constructing it through a sequence of @code{--install} and similar
2852 commands. The advantage is that @var{file} can be put under version
2853 control, copied to different machines to reproduce the same profile, and
2856 @c FIXME: Add reference to (guix profile) documentation when available.
2857 @var{file} must return a @dfn{manifest} object, which is roughly a list
2860 @findex packages->manifest
2862 (use-package-modules guile emacs)
2867 ;; Use a specific package output.
2868 (list guile-2.0 "debug")))
2871 @findex specifications->manifest
2872 In this example we have to know which modules define the @code{emacs}
2873 and @code{guile-2.0} variables to provide the right
2874 @code{use-package-modules} line, which can be cumbersome. We can
2875 instead provide regular package specifications and let
2876 @code{specifications->manifest} look up the corresponding package
2880 (specifications->manifest
2881 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2885 @cindex rolling back
2886 @cindex undoing transactions
2887 @cindex transactions, undoing
2888 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2889 the last transaction.
2891 When combined with options such as @code{--install}, roll back occurs
2892 before any other actions.
2894 When rolling back from the first generation that actually contains
2895 installed packages, the profile is made to point to the @dfn{zeroth
2896 generation}, which contains no files apart from its own metadata.
2898 After having rolled back, installing, removing, or upgrading packages
2899 overwrites previous future generations. Thus, the history of the
2900 generations in a profile is always linear.
2902 @item --switch-generation=@var{pattern}
2903 @itemx -S @var{pattern}
2905 Switch to a particular generation defined by @var{pattern}.
2907 @var{pattern} may be either a generation number or a number prefixed
2908 with ``+'' or ``-''. The latter means: move forward/backward by a
2909 specified number of generations. For example, if you want to return to
2910 the latest generation after @code{--roll-back}, use
2911 @code{--switch-generation=+1}.
2913 The difference between @code{--roll-back} and
2914 @code{--switch-generation=-1} is that @code{--switch-generation} will
2915 not make a zeroth generation, so if a specified generation does not
2916 exist, the current generation will not be changed.
2918 @item --search-paths[=@var{kind}]
2919 @cindex search paths
2920 Report environment variable definitions, in Bash syntax, that may be
2921 needed in order to use the set of installed packages. These environment
2922 variables are used to specify @dfn{search paths} for files used by some
2923 of the installed packages.
2925 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2926 environment variables to be defined so it can look for headers and
2927 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2928 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2929 library are installed in the profile, then @code{--search-paths} will
2930 suggest setting these variables to @code{@var{profile}/include} and
2931 @code{@var{profile}/lib}, respectively.
2933 The typical use case is to define these environment variables in the
2937 $ eval `guix package --search-paths`
2940 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2941 meaning that the returned environment variable definitions will either
2942 be exact settings, or prefixes or suffixes of the current value of these
2943 variables. When omitted, @var{kind} defaults to @code{exact}.
2945 This option can also be used to compute the @emph{combined} search paths
2946 of several profiles. Consider this example:
2949 $ guix package -p foo -i guile
2950 $ guix package -p bar -i guile-json
2951 $ guix package -p foo -p bar --search-paths
2954 The last command above reports about the @code{GUILE_LOAD_PATH}
2955 variable, even though, taken individually, neither @file{foo} nor
2956 @file{bar} would lead to that recommendation.
2959 @item --profile=@var{profile}
2960 @itemx -p @var{profile}
2961 Use @var{profile} instead of the user's default profile.
2963 @var{profile} must be the name of a file that will be created upon
2964 completion. Concretely, @var{profile} will be a mere symbolic link
2965 (``symlink'') pointing to the actual profile where packages are
2969 $ guix install hello -p ~/code/my-profile
2971 $ ~/code/my-profile/bin/hello
2975 All it takes to get rid of the profile is to remove this symlink and its
2976 siblings that point to specific generations:
2979 $ rm ~/code/my-profile ~/code/my-profile-*-link
2982 @item --list-profiles
2983 List all the user's profiles:
2986 $ guix package --list-profiles
2987 /home/charlie/.guix-profile
2988 /home/charlie/code/my-profile
2989 /home/charlie/code/devel-profile
2990 /home/charlie/tmp/test
2993 When running as root, list all the profiles of all the users.
2995 @cindex collisions, in a profile
2996 @cindex colliding packages in profiles
2997 @cindex profile collisions
2998 @item --allow-collisions
2999 Allow colliding packages in the new profile. Use at your own risk!
3001 By default, @command{guix package} reports as an error @dfn{collisions}
3002 in the profile. Collisions happen when two or more different versions
3003 or variants of a given package end up in the profile.
3006 Use the bootstrap Guile to build the profile. This option is only
3007 useful to distribution developers.
3011 In addition to these actions, @command{guix package} supports the
3012 following options to query the current state of a profile, or the
3013 availability of packages:
3017 @item --search=@var{regexp}
3018 @itemx -s @var{regexp}
3019 @cindex searching for packages
3020 List the available packages whose name, synopsis, or description matches
3021 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3022 Print all the metadata of matching packages in
3023 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3024 GNU recutils manual}).
3026 This allows specific fields to be extracted using the @command{recsel}
3027 command, for instance:
3030 $ guix package -s malloc | recsel -p name,version,relevance
3044 Similarly, to show the name of all the packages available under the
3045 terms of the GNU@tie{}LGPL version 3:
3048 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3055 It is also possible to refine search results using several @code{-s} flags to
3056 @command{guix package}, or several arguments to @command{guix search}. For
3057 example, the following command returns a list of board games (this time using
3058 the @command{guix search} alias):
3061 $ guix search '\<board\>' game | recsel -p name
3066 If we were to omit @code{-s game}, we would also get software packages
3067 that deal with printed circuit boards; removing the angle brackets
3068 around @code{board} would further add packages that have to do with
3071 And now for a more elaborate example. The following command searches
3072 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3073 libraries, and prints the name and synopsis of the matching packages:
3076 $ guix search crypto library | \
3077 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3081 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3082 information on @dfn{selection expressions} for @code{recsel -e}.
3084 @item --show=@var{package}
3085 Show details about @var{package}, taken from the list of available packages, in
3086 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3090 $ guix package --show=python | recsel -p name,version
3098 You may also specify the full name of a package to only get details about a
3099 specific version of it (this time using the @command{guix show} alias):
3101 $ guix show python@@3.4 | recsel -p name,version
3108 @item --list-installed[=@var{regexp}]
3109 @itemx -I [@var{regexp}]
3110 List the currently installed packages in the specified profile, with the
3111 most recently installed packages shown last. When @var{regexp} is
3112 specified, list only installed packages whose name matches @var{regexp}.
3114 For each installed package, print the following items, separated by
3115 tabs: the package name, its version string, the part of the package that
3116 is installed (for instance, @code{out} for the default output,
3117 @code{include} for its headers, etc.), and the path of this package in
3120 @item --list-available[=@var{regexp}]
3121 @itemx -A [@var{regexp}]
3122 List packages currently available in the distribution for this system
3123 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3124 installed packages whose name matches @var{regexp}.
3126 For each package, print the following items separated by tabs: its name,
3127 its version string, the parts of the package (@pxref{Packages with
3128 Multiple Outputs}), and the source location of its definition.
3130 @item --list-generations[=@var{pattern}]
3131 @itemx -l [@var{pattern}]
3133 Return a list of generations along with their creation dates; for each
3134 generation, show the installed packages, with the most recently
3135 installed packages shown last. Note that the zeroth generation is never
3138 For each installed package, print the following items, separated by
3139 tabs: the name of a package, its version string, the part of the package
3140 that is installed (@pxref{Packages with Multiple Outputs}), and the
3141 location of this package in the store.
3143 When @var{pattern} is used, the command returns only matching
3144 generations. Valid patterns include:
3147 @item @emph{Integers and comma-separated integers}. Both patterns denote
3148 generation numbers. For instance, @code{--list-generations=1} returns
3151 And @code{--list-generations=1,8,2} outputs three generations in the
3152 specified order. Neither spaces nor trailing commas are allowed.
3154 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3155 specified generations and everything in between. Note that the start of
3156 a range must be smaller than its end.
3158 It is also possible to omit the endpoint. For example,
3159 @code{--list-generations=2..}, returns all generations starting from the
3162 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3163 or months by passing an integer along with the first letter of the
3164 duration. For example, @code{--list-generations=20d} lists generations
3165 that are up to 20 days old.
3168 @item --delete-generations[=@var{pattern}]
3169 @itemx -d [@var{pattern}]
3170 When @var{pattern} is omitted, delete all generations except the current
3173 This command accepts the same patterns as @option{--list-generations}.
3174 When @var{pattern} is specified, delete the matching generations. When
3175 @var{pattern} specifies a duration, generations @emph{older} than the
3176 specified duration match. For instance, @code{--delete-generations=1m}
3177 deletes generations that are more than one month old.
3179 If the current generation matches, it is @emph{not} deleted. Also, the
3180 zeroth generation is never deleted.
3182 Note that deleting generations prevents rolling back to them.
3183 Consequently, this command must be used with care.
3187 Finally, since @command{guix package} may actually start build
3188 processes, it supports all the common build options (@pxref{Common Build
3189 Options}). It also supports package transformation options, such as
3190 @option{--with-source} (@pxref{Package Transformation Options}).
3191 However, note that package transformations are lost when upgrading; to
3192 preserve transformations across upgrades, you should define your own
3193 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3194 (@pxref{Defining Packages}).
3197 @section Substitutes
3200 @cindex pre-built binaries
3201 Guix supports transparent source/binary deployment, which means that it
3202 can either build things locally, or download pre-built items from a
3203 server, or both. We call these pre-built items @dfn{substitutes}---they
3204 are substitutes for local build results. In many cases, downloading a
3205 substitute is much faster than building things locally.
3207 Substitutes can be anything resulting from a derivation build
3208 (@pxref{Derivations}). Of course, in the common case, they are
3209 pre-built package binaries, but source tarballs, for instance, which
3210 also result from derivation builds, can be available as substitutes.
3213 * Official Substitute Server:: One particular source of substitutes.
3214 * Substitute Server Authorization:: How to enable or disable substitutes.
3215 * Substitute Authentication:: How Guix verifies substitutes.
3216 * Proxy Settings:: How to get substitutes via proxy.
3217 * Substitution Failure:: What happens when substitution fails.
3218 * On Trusting Binaries:: How can you trust that binary blob?
3221 @node Official Substitute Server
3222 @subsection Official Substitute Server
3225 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3226 that builds packages from Guix continuously for some
3227 architectures, and makes them available as substitutes. This is the
3228 default source of substitutes; it can be overridden by passing the
3229 @option{--substitute-urls} option either to @command{guix-daemon}
3230 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3231 or to client tools such as @command{guix package}
3232 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3235 Substitute URLs can be either HTTP or HTTPS.
3236 HTTPS is recommended because communications are encrypted; conversely,
3237 using HTTP makes all communications visible to an eavesdropper, who
3238 could use the information gathered to determine, for instance, whether
3239 your system has unpatched security vulnerabilities.
3241 Substitutes from the official build farm are enabled by default when
3242 using Guix System (@pxref{GNU Distribution}). However,
3243 they are disabled by default when using Guix on a foreign distribution,
3244 unless you have explicitly enabled them via one of the recommended
3245 installation steps (@pxref{Installation}). The following paragraphs
3246 describe how to enable or disable substitutes for the official build
3247 farm; the same procedure can also be used to enable substitutes for any
3248 other substitute server.
3250 @node Substitute Server Authorization
3251 @subsection Substitute Server Authorization
3254 @cindex substitutes, authorization thereof
3255 @cindex access control list (ACL), for substitutes
3256 @cindex ACL (access control list), for substitutes
3257 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3259 must add its public key to the access control list (ACL) of archive
3260 imports, using the @command{guix archive} command (@pxref{Invoking guix
3261 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3262 be compromised and to serve genuine substitutes.
3264 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3265 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3266 the installation prefix of Guix. If you installed Guix from source,
3267 make sure you checked the GPG signature of
3268 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3269 Then, you can run something like this:
3272 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3275 Once this is in place, the output of a command like @code{guix build}
3276 should change from something like:
3279 $ guix build emacs --dry-run
3280 The following derivations would be built:
3281 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3282 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3283 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3284 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3292 $ guix build emacs --dry-run
3293 112.3 MB would be downloaded:
3294 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3295 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3296 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3297 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3302 The text changed from ``The following derivations would be built'' to
3303 ``112.3 MB would be downloaded''. This indicates that substitutes from
3304 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3305 possible, for future builds.
3307 @cindex substitutes, how to disable
3308 The substitute mechanism can be disabled globally by running
3309 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3310 guix-daemon}). It can also be disabled temporarily by passing the
3311 @code{--no-substitutes} option to @command{guix package}, @command{guix
3312 build}, and other command-line tools.
3314 @node Substitute Authentication
3315 @subsection Substitute Authentication
3317 @cindex digital signatures
3318 Guix detects and raises an error when attempting to use a substitute
3319 that has been tampered with. Likewise, it ignores substitutes that are
3320 not signed, or that are not signed by one of the keys listed in the ACL.
3322 There is one exception though: if an unauthorized server provides
3323 substitutes that are @emph{bit-for-bit identical} to those provided by
3324 an authorized server, then the unauthorized server becomes eligible for
3325 downloads. For example, assume we have chosen two substitute servers
3329 --substitute-urls="https://a.example.org https://b.example.org"
3333 @cindex reproducible builds
3334 If the ACL contains only the key for @code{b.example.org}, and if
3335 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3336 then Guix will download substitutes from @code{a.example.org} because it
3337 comes first in the list and can be considered a mirror of
3338 @code{b.example.org}. In practice, independent build machines usually
3339 produce the same binaries, thanks to bit-reproducible builds (see
3342 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3343 (in other words, the server is not authenticated), contrary to what
3344 HTTPS clients such as Web browsers usually do. This is because Guix
3345 authenticates substitute information itself, as explained above, which
3346 is what we care about (whereas X.509 certificates are about
3347 authenticating bindings between domain names and public keys.)
3349 @node Proxy Settings
3350 @subsection Proxy Settings
3353 Substitutes are downloaded over HTTP or HTTPS.
3354 The @code{http_proxy} environment
3355 variable can be set in the environment of @command{guix-daemon} and is
3356 honored for downloads of substitutes. Note that the value of
3357 @code{http_proxy} in the environment where @command{guix build},
3358 @command{guix package}, and other client commands are run has
3359 @emph{absolutely no effect}.
3361 @node Substitution Failure
3362 @subsection Substitution Failure
3364 Even when a substitute for a derivation is available, sometimes the
3365 substitution attempt will fail. This can happen for a variety of
3366 reasons: the substitute server might be offline, the substitute may
3367 recently have been deleted, the connection might have been interrupted,
3370 When substitutes are enabled and a substitute for a derivation is
3371 available, but the substitution attempt fails, Guix will attempt to
3372 build the derivation locally depending on whether or not
3373 @code{--fallback} was given (@pxref{fallback-option,, common build
3374 option @code{--fallback}}). Specifically, if @code{--fallback} was
3375 omitted, then no local build will be performed, and the derivation is
3376 considered to have failed. However, if @code{--fallback} was given,
3377 then Guix will attempt to build the derivation locally, and the success
3378 or failure of the derivation depends on the success or failure of the
3379 local build. Note that when substitutes are disabled or no substitute
3380 is available for the derivation in question, a local build will
3381 @emph{always} be performed, regardless of whether or not
3382 @code{--fallback} was given.
3384 To get an idea of how many substitutes are available right now, you can
3385 try running the @command{guix weather} command (@pxref{Invoking guix
3386 weather}). This command provides statistics on the substitutes provided
3389 @node On Trusting Binaries
3390 @subsection On Trusting Binaries
3392 @cindex trust, of pre-built binaries
3393 Today, each individual's control over their own computing is at the
3394 mercy of institutions, corporations, and groups with enough power and
3395 determination to subvert the computing infrastructure and exploit its
3396 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3397 convenient, we encourage users to also build on their own, or even run
3398 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3399 interesting target. One way to help is by publishing the software you
3400 build using @command{guix publish} so that others have one more choice
3401 of server to download substitutes from (@pxref{Invoking guix publish}).
3403 Guix has the foundations to maximize build reproducibility
3404 (@pxref{Features}). In most cases, independent builds of a given
3405 package or derivation should yield bit-identical results. Thus, through
3406 a diverse set of independent package builds, we can strengthen the
3407 integrity of our systems. The @command{guix challenge} command aims to
3408 help users assess substitute servers, and to assist developers in
3409 finding out about non-deterministic package builds (@pxref{Invoking guix
3410 challenge}). Similarly, the @option{--check} option of @command{guix
3411 build} allows users to check whether previously-installed substitutes
3412 are genuine by rebuilding them locally (@pxref{build-check,
3413 @command{guix build --check}}).
3415 In the future, we want Guix to have support to publish and retrieve
3416 binaries to/from other users, in a peer-to-peer fashion. If you would
3417 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3419 @node Packages with Multiple Outputs
3420 @section Packages with Multiple Outputs
3422 @cindex multiple-output packages
3423 @cindex package outputs
3426 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3427 source package leads to exactly one directory in the store. When running
3428 @command{guix install glibc}, one installs the default output of the
3429 GNU libc package; the default output is called @code{out}, but its name
3430 can be omitted as shown in this command. In this particular case, the
3431 default output of @code{glibc} contains all the C header files, shared
3432 libraries, static libraries, Info documentation, and other supporting
3435 Sometimes it is more appropriate to separate the various types of files
3436 produced from a single source package into separate outputs. For
3437 instance, the GLib C library (used by GTK+ and related packages)
3438 installs more than 20 MiB of reference documentation as HTML pages.
3439 To save space for users who do not need it, the documentation goes to a
3440 separate output, called @code{doc}. To install the main GLib output,
3441 which contains everything but the documentation, one would run:
3447 @cindex documentation
3448 The command to install its documentation is:
3451 guix install glib:doc
3454 Some packages install programs with different ``dependency footprints''.
3455 For instance, the WordNet package installs both command-line tools and
3456 graphical user interfaces (GUIs). The former depend solely on the C
3457 library, whereas the latter depend on Tcl/Tk and the underlying X
3458 libraries. In this case, we leave the command-line tools in the default
3459 output, whereas the GUIs are in a separate output. This allows users
3460 who do not need the GUIs to save space. The @command{guix size} command
3461 can help find out about such situations (@pxref{Invoking guix size}).
3462 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3464 There are several such multiple-output packages in the GNU distribution.
3465 Other conventional output names include @code{lib} for libraries and
3466 possibly header files, @code{bin} for stand-alone programs, and
3467 @code{debug} for debugging information (@pxref{Installing Debugging
3468 Files}). The outputs of a packages are listed in the third column of
3469 the output of @command{guix package --list-available} (@pxref{Invoking
3473 @node Invoking guix gc
3474 @section Invoking @command{guix gc}
3476 @cindex garbage collector
3478 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3479 The @command{guix gc} command allows users to explicitly run the garbage
3480 collector to reclaim space from the @file{/gnu/store} directory. It is
3481 the @emph{only} way to remove files from @file{/gnu/store}---removing
3482 files or directories manually may break it beyond repair!
3485 @cindex garbage collector roots
3486 The garbage collector has a set of known @dfn{roots}: any file under
3487 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3488 cannot be deleted; any other file is considered @dfn{dead} and may be
3489 deleted. The set of garbage collector roots (``GC roots'' for short)
3490 includes default user profiles; by default, the symlinks under
3491 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3492 added with @command{guix build --root}, for example (@pxref{Invoking
3493 guix build}). The @command{guix gc --list-roots} command lists them.
3495 Prior to running @code{guix gc --collect-garbage} to make space, it is
3496 often useful to remove old generations from user profiles; that way, old
3497 package builds referenced by those generations can be reclaimed. This
3498 is achieved by running @code{guix package --delete-generations}
3499 (@pxref{Invoking guix package}).
3501 Our recommendation is to run a garbage collection periodically, or when
3502 you are short on disk space. For instance, to guarantee that at least
3503 5@tie{}GB are available on your disk, simply run:
3509 It is perfectly safe to run as a non-interactive periodic job
3510 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3511 Running @command{guix gc} with no arguments will collect as
3512 much garbage as it can, but that is often inconvenient: you may find
3513 yourself having to rebuild or re-download software that is ``dead'' from
3514 the GC viewpoint but that is necessary to build other pieces of
3515 software---e.g., the compiler tool chain.
3517 The @command{guix gc} command has three modes of operation: it can be
3518 used to garbage-collect any dead files (the default), to delete specific
3519 files (the @code{--delete} option), to print garbage-collector
3520 information, or for more advanced queries. The garbage collection
3521 options are as follows:
3524 @item --collect-garbage[=@var{min}]
3525 @itemx -C [@var{min}]
3526 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3527 sub-directories. This is the default operation when no option is
3530 When @var{min} is given, stop once @var{min} bytes have been collected.
3531 @var{min} may be a number of bytes, or it may include a unit as a
3532 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3533 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3535 When @var{min} is omitted, collect all the garbage.
3537 @item --free-space=@var{free}
3538 @itemx -F @var{free}
3539 Collect garbage until @var{free} space is available under
3540 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3541 as @code{500MiB}, as described above.
3543 When @var{free} or more is already available in @file{/gnu/store}, do
3544 nothing and exit immediately.
3546 @item --delete-generations[=@var{duration}]
3547 @itemx -d [@var{duration}]
3548 Before starting the garbage collection process, delete all the generations
3549 older than @var{duration}, for all the user profiles; when run as root, this
3550 applies to all the profiles @emph{of all the users}.
3552 For example, this command deletes all the generations of all your profiles
3553 that are older than 2 months (except generations that are current), and then
3554 proceeds to free space until at least 10 GiB are available:
3557 guix gc -d 2m -F 10G
3562 Attempt to delete all the store files and directories specified as
3563 arguments. This fails if some of the files are not in the store, or if
3564 they are still live.
3566 @item --list-failures
3567 List store items corresponding to cached build failures.
3569 This prints nothing unless the daemon was started with
3570 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3571 @option{--cache-failures}}).
3574 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3578 List store items in use by currently running processes. These store
3579 items are effectively considered GC roots: they cannot be deleted.
3581 @item --clear-failures
3582 Remove the specified store items from the failed-build cache.
3584 Again, this option only makes sense when the daemon is started with
3585 @option{--cache-failures}. Otherwise, it does nothing.
3588 Show the list of dead files and directories still present in the
3589 store---i.e., files and directories no longer reachable from any root.
3592 Show the list of live store files and directories.
3596 In addition, the references among existing store files can be queried:
3602 @cindex package dependencies
3603 List the references (respectively, the referrers) of store files given
3609 List the requisites of the store files passed as arguments. Requisites
3610 include the store files themselves, their references, and the references
3611 of these, recursively. In other words, the returned list is the
3612 @dfn{transitive closure} of the store files.
3614 @xref{Invoking guix size}, for a tool to profile the size of the closure
3615 of an element. @xref{Invoking guix graph}, for a tool to visualize
3616 the graph of references.
3620 Return the derivation(s) leading to the given store items
3621 (@pxref{Derivations}).
3623 For example, this command:
3626 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3630 returns the @file{.drv} file(s) leading to the @code{emacs} package
3631 installed in your profile.
3633 Note that there may be zero matching @file{.drv} files, for instance
3634 because these files have been garbage-collected. There can also be more
3635 than one matching @file{.drv} due to fixed-output derivations.
3638 Lastly, the following options allow you to check the integrity of the
3639 store and to control disk usage.
3643 @item --verify[=@var{options}]
3644 @cindex integrity, of the store
3645 @cindex integrity checking
3646 Verify the integrity of the store.
3648 By default, make sure that all the store items marked as valid in the
3649 database of the daemon actually exist in @file{/gnu/store}.
3651 When provided, @var{options} must be a comma-separated list containing one
3652 or more of @code{contents} and @code{repair}.
3654 When passing @option{--verify=contents}, the daemon computes the
3655 content hash of each store item and compares it against its hash in the
3656 database. Hash mismatches are reported as data corruptions. Because it
3657 traverses @emph{all the files in the store}, this command can take a
3658 long time, especially on systems with a slow disk drive.
3660 @cindex repairing the store
3661 @cindex corruption, recovering from
3662 Using @option{--verify=repair} or @option{--verify=contents,repair}
3663 causes the daemon to try to repair corrupt store items by fetching
3664 substitutes for them (@pxref{Substitutes}). Because repairing is not
3665 atomic, and thus potentially dangerous, it is available only to the
3666 system administrator. A lightweight alternative, when you know exactly
3667 which items in the store are corrupt, is @command{guix build --repair}
3668 (@pxref{Invoking guix build}).
3671 @cindex deduplication
3672 Optimize the store by hard-linking identical files---this is
3673 @dfn{deduplication}.
3675 The daemon performs deduplication after each successful build or archive
3676 import, unless it was started with @code{--disable-deduplication}
3677 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3678 this option is primarily useful when the daemon was running with
3679 @code{--disable-deduplication}.
3683 @node Invoking guix pull
3684 @section Invoking @command{guix pull}
3686 @cindex upgrading Guix
3687 @cindex updating Guix
3688 @cindex @command{guix pull}
3690 Packages are installed or upgraded to the latest version available in
3691 the distribution currently available on your local machine. To update
3692 that distribution, along with the Guix tools, you must run @command{guix
3693 pull}: the command downloads the latest Guix source code and package
3694 descriptions, and deploys it. Source code is downloaded from a
3695 @uref{https://git-scm.com, Git} repository, by default the official
3696 GNU@tie{}Guix repository, though this can be customized.
3698 Specifically, @command{guix pull} downloads code from the @dfn{channels}
3699 (@pxref{Channels}) specified by one of the followings, in this order:
3703 the @option{--channels} option;
3705 the user's @file{~/.config/guix/channels.scm} file;
3707 the system-wide @file{/etc/guix/channels.scm} file;
3709 the built-in default channels specified in the @code{%default-channels}
3713 On completion, @command{guix package} will use packages and package
3714 versions from this just-retrieved copy of Guix. Not only that, but all
3715 the Guix commands and Scheme modules will also be taken from that latest
3716 version. New @command{guix} sub-commands added by the update also
3719 Any user can update their Guix copy using @command{guix pull}, and the
3720 effect is limited to the user who ran @command{guix pull}. For
3721 instance, when user @code{root} runs @command{guix pull}, this has no
3722 effect on the version of Guix that user @code{alice} sees, and vice
3725 The result of running @command{guix pull} is a @dfn{profile} available
3726 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3727 make sure to add it to the beginning of your search path so that you use
3728 the latest version, and similarly for the Info manual
3729 (@pxref{Documentation}):
3732 export PATH="$HOME/.config/guix/current/bin:$PATH"
3733 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3736 The @code{--list-generations} or @code{-l} option lists past generations
3737 produced by @command{guix pull}, along with details about their provenance:
3741 Generation 1 Jun 10 2018 00:18:18
3743 repository URL: https://git.savannah.gnu.org/git/guix.git
3744 branch: origin/master
3745 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3747 Generation 2 Jun 11 2018 11:02:49
3749 repository URL: https://git.savannah.gnu.org/git/guix.git
3750 branch: origin/master
3751 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3752 2 new packages: keepalived, libnfnetlink
3753 6 packages upgraded: emacs-nix-mode@@2.0.4,
3754 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3755 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3757 Generation 3 Jun 13 2018 23:31:07 (current)
3759 repository URL: https://git.savannah.gnu.org/git/guix.git
3760 branch: origin/master
3761 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3762 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3763 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3766 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3767 describe the current status of Guix.
3769 This @code{~/.config/guix/current} profile works exactly like the profiles
3770 created by @command{guix package} (@pxref{Invoking guix package}). That
3771 is, you can list generations, roll back to the previous
3772 generation---i.e., the previous Guix---and so on:
3775 $ guix pull --roll-back
3776 switched from generation 3 to 2
3777 $ guix pull --delete-generations=1
3778 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3781 You can also use @command{guix package} (@pxref{Invoking guix package})
3782 to manage the profile by naming it explicitly:
3784 $ guix package -p ~/.config/guix/current --roll-back
3785 switched from generation 3 to 2
3786 $ guix package -p ~/.config/guix/current --delete-generations=1
3787 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3790 The @command{guix pull} command is usually invoked with no arguments,
3791 but it supports the following options:
3794 @item --url=@var{url}
3795 @itemx --commit=@var{commit}
3796 @itemx --branch=@var{branch}
3797 Download code for the @code{guix} channel from the specified @var{url}, at the
3798 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3799 string), or @var{branch}.
3801 @cindex @file{channels.scm}, configuration file
3802 @cindex configuration file for channels
3803 These options are provided for convenience, but you can also specify your
3804 configuration in the @file{~/.config/guix/channels.scm} file or using the
3805 @option{--channels} option (see below).
3807 @item --channels=@var{file}
3808 @itemx -C @var{file}
3809 Read the list of channels from @var{file} instead of
3810 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
3811 @var{file} must contain Scheme code that
3812 evaluates to a list of channel objects. @xref{Channels}, for more
3815 @cindex channel news
3818 Display the list of packages added or upgraded since the previous
3819 generation, as well as, occasionally, news written by channel authors
3820 for their users (@pxref{Channels, Writing Channel News}).
3822 The package information is the same as displayed upon @command{guix
3823 pull} completion, but without ellipses; it is also similar to the output
3824 of @command{guix pull -l} for the last generation (see below).
3826 @item --list-generations[=@var{pattern}]
3827 @itemx -l [@var{pattern}]
3828 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3829 is provided, the subset of generations that match @var{pattern}.
3830 The syntax of @var{pattern} is the same as with @code{guix package
3831 --list-generations} (@pxref{Invoking guix package}).
3834 @cindex rolling back
3835 @cindex undoing transactions
3836 @cindex transactions, undoing
3837 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
3838 undo the last transaction.
3840 @item --switch-generation=@var{pattern}
3841 @itemx -S @var{pattern}
3843 Switch to a particular generation defined by @var{pattern}.
3845 @var{pattern} may be either a generation number or a number prefixed
3846 with ``+'' or ``-''. The latter means: move forward/backward by a
3847 specified number of generations. For example, if you want to return to
3848 the latest generation after @code{--roll-back}, use
3849 @code{--switch-generation=+1}.
3851 @item --delete-generations[=@var{pattern}]
3852 @itemx -d [@var{pattern}]
3853 When @var{pattern} is omitted, delete all generations except the current
3856 This command accepts the same patterns as @option{--list-generations}.
3857 When @var{pattern} is specified, delete the matching generations. When
3858 @var{pattern} specifies a duration, generations @emph{older} than the
3859 specified duration match. For instance, @code{--delete-generations=1m}
3860 deletes generations that are more than one month old.
3862 If the current generation matches, it is @emph{not} deleted.
3864 Note that deleting generations prevents rolling back to them.
3865 Consequently, this command must be used with care.
3867 @xref{Invoking guix describe}, for a way to display information about the
3868 current generation only.
3870 @item --profile=@var{profile}
3871 @itemx -p @var{profile}
3872 Use @var{profile} instead of @file{~/.config/guix/current}.
3876 Show which channel commit(s) would be used and what would be built or
3877 substituted but do not actually do it.
3879 @item --system=@var{system}
3880 @itemx -s @var{system}
3881 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3882 the system type of the build host.
3885 Produce verbose output, writing build logs to the standard error output.
3888 Use the bootstrap Guile to build the latest Guix. This option is only
3889 useful to Guix developers.
3892 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3893 repository and branch to pull from, as well as @emph{additional} repositories
3894 containing package modules that should be deployed. @xref{Channels}, for more
3897 In addition, @command{guix pull} supports all the common build options
3898 (@pxref{Common Build Options}).
3904 @cindex @file{channels.scm}, configuration file
3905 @cindex configuration file for channels
3906 @cindex @command{guix pull}, configuration file
3907 @cindex configuration of @command{guix pull}
3908 Guix and its package collection are updated by running @command{guix pull}
3909 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3910 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3911 customized by defining @dfn{channels} in the
3912 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3913 of a Git repository to be deployed, and @command{guix pull} can be instructed
3914 to pull from one or more channels. In other words, channels can be used to
3915 @emph{customize} and to @emph{extend} Guix, as we will see below.
3917 @subsection Using a Custom Guix Channel
3919 The channel called @code{guix} specifies where Guix itself---its command-line
3920 tools as well as its package collection---should be downloaded. For instance,
3921 suppose you want to update from your own copy of the Guix repository at
3922 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3923 write in @code{~/.config/guix/channels.scm} this specification:
3926 ;; Tell 'guix pull' to use my own repo.
3929 (url "https://example.org/my-guix.git")
3930 (branch "super-hacks")))
3934 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3935 branch of the repository at @code{example.org}.
3937 @subsection Specifying Additional Channels
3939 @cindex extending the package collection (channels)
3940 @cindex personal packages (channels)
3941 @cindex channels, for personal packages
3942 You can also specify @emph{additional channels} to pull from. Let's say you
3943 have a bunch of custom package variants or personal packages that you think
3944 would make little sense to contribute to the Guix project, but would like to
3945 have these packages transparently available to you at the command line. You
3946 would first write modules containing those package definitions (@pxref{Package
3947 Modules}), maintain them in a Git repository, and then you and anyone else can
3948 use it as an additional channel to get packages from. Neat, no?
3950 @c What follows stems from discussions at
3951 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3952 @c earlier discussions on guix-devel@gnu.org.
3954 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3955 publish your personal channel to the world, we would like to share a few words
3960 Before publishing a channel, please consider contributing your package
3961 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3962 to free software of all sorts, and packages in Guix proper are readily
3963 available to all Guix users and benefit from the project's quality assurance
3967 When you maintain package definitions outside Guix, we, Guix developers,
3968 consider that @emph{the compatibility burden is on you}. Remember that
3969 package modules and package definitions are just Scheme code that uses various
3970 programming interfaces (APIs). We want to remain free to change these APIs to
3971 keep improving Guix, possibly in ways that break your channel. We never
3972 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
3976 Corollary: if you're using an external channel and that channel breaks, please
3977 @emph{report the issue to the channel authors}, not to the Guix project.
3980 You've been warned! Having said this, we believe external channels are a
3981 practical way to exert your freedom to augment Guix' package collection and to
3982 share your improvements, which are basic tenets of
3983 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
3984 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
3987 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
3988 @command{guix pull} to pull from it @emph{in addition} to the default Guix
3991 @vindex %default-channels
3993 ;; Add my personal packages to those Guix provides.
3995 (name 'my-personal-packages)
3996 (url "https://example.org/personal-packages.git"))
4001 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4002 add a channel the list of channels that the variable @code{%default-channels}
4003 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4004 Manual}). With this file in place, @command{guix pull} builds not only Guix
4005 but also the package modules from your own repository. The result in
4006 @file{~/.config/guix/current} is the union of Guix with your own package
4010 $ guix pull --list-generations
4012 Generation 19 Aug 27 2018 16:20:48
4014 repository URL: https://git.savannah.gnu.org/git/guix.git
4016 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4017 my-personal-packages dd3df5e
4018 repository URL: https://example.org/personal-packages.git
4020 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4021 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
4022 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4026 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4027 both Guix and packages from the @code{my-personal-packages} channel. Among
4028 the new and upgraded packages that are listed, some like @code{my-gimp} and
4029 @code{my-emacs-with-cool-features} might come from
4030 @code{my-personal-packages}, while others come from the Guix default channel.
4032 To create a channel, create a Git repository containing your own package
4033 modules and make it available. The repository can contain anything, but a
4034 useful channel will contain Guile modules that export packages. Once you
4035 start using a channel, Guix will behave as if the root directory of that
4036 channel's Git repository has been added to the Guile load path (@pxref{Load
4037 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
4038 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
4039 module, then the module will be available under the name @code{(my-packages
4040 my-tools)}, and you will be able to use it like any other module
4041 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
4043 @cindex dependencies, channels
4044 @cindex meta-data, channels
4045 @subsection Declaring Channel Dependencies
4047 Channel authors may decide to augment a package collection provided by other
4048 channels. They can declare their channel to be dependent on other channels in
4049 a meta-data file @file{.guix-channel}, which is to be placed in the root of
4050 the channel repository.
4052 The meta-data file should contain a simple S-expression like this:
4059 (name some-collection)
4060 (url "https://example.org/first-collection.git"))
4062 (name some-other-collection)
4063 (url "https://example.org/second-collection.git")
4064 (branch "testing"))))
4067 In the above example this channel is declared to depend on two other channels,
4068 which will both be fetched automatically. The modules provided by the channel
4069 will be compiled in an environment where the modules of all these declared
4070 channels are available.
4072 For the sake of reliability and maintainability, you should avoid dependencies
4073 on channels that you don't control, and you should aim to keep the number of
4074 dependencies to a minimum.
4076 @cindex subdirectory, channels
4077 @subsection Package Modules in a Sub-directory
4079 As a channel author, you may want to keep your channel modules in a
4080 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4081 add a meta-data file @file{.guix-channel} that contains:
4089 @cindex news, for channels
4090 @subsection Writing Channel News
4092 Channel authors may occasionally want to communicate to their users
4093 information about important changes in the channel. You'd send them all
4094 an email, but that's not convenient.
4096 Instead, channels can provide a @dfn{news file}; when the channel users
4097 run @command{guix pull}, that news file is automatically read and
4098 @command{guix pull --news} can display the announcements that correspond
4099 to the new commits that have been pulled, if any.
4101 To do that, channel authors must first declare the name of the news file
4102 in their @file{.guix-channel} file:
4107 (news-file "etc/news.txt"))
4110 The news file itself, @file{etc/news.txt} in this example, must look
4111 something like this:
4116 (entry (tag "the-bug-fix")
4117 (title (en "Fixed terrible bug")
4119 (body (en "@@emph@{Good news@}! It's fixed!")
4120 (eo "Certe ĝi pli bone funkcias nun!")))
4121 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4122 (title (en "Added a great package")
4123 (ca "Què vol dir guix?"))
4124 (body (en "Don't miss the @@code@{hello@} package!"))))
4127 The file consists of a list of @dfn{news entries}. Each entry is
4128 associated with a commit or tag: it describes changes made in this
4129 commit, possibly in preceding commits as well. Users see entries only
4130 the first time they obtain the commit the entry refers to.
4132 The @code{title} field should be a one-line summary while @code{body}
4133 can be arbitrarily long, and both can contain Texinfo markup
4134 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4135 a list of language tag/message tuples, which allows @command{guix pull}
4136 to display news in the language that corresponds to the user's locale.
4138 If you want to translate news using a gettext-based workflow, you can
4139 extract translatable strings with @command{xgettext} (@pxref{xgettext
4140 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4141 you write news entries in English first, the command below creates a PO
4142 file containing the strings to translate:
4145 xgettext -o news.po -l scheme -ken etc/news.scm
4148 To sum up, yes, you could use your channel as a blog. But beware, this
4149 is @emph{not quite} what your users might expect.
4151 @subsection Replicating Guix
4153 @cindex pinning, channels
4154 @cindex replicating Guix
4155 @cindex reproducibility, of Guix
4156 The @command{guix pull --list-generations} output above shows precisely which
4157 commits were used to build this instance of Guix. We can thus replicate it,
4158 say, on another machine, by providing a channel specification in
4159 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4162 ;; Deploy specific commits of my channels of interest.
4165 (url "https://git.savannah.gnu.org/git/guix.git")
4166 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
4168 (name 'my-personal-packages)
4169 (url "https://example.org/personal-packages.git")
4170 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4173 The @command{guix describe --format=channels} command can even generate this
4174 list of channels directly (@pxref{Invoking guix describe}). The resulting
4175 file can be used with the -C options of @command{guix pull}
4176 (@pxref{Invoking guix pull}) or @command{guix time-machine}
4177 (@pxref{Invoking guix time-machine}).
4179 At this point the two machines run the @emph{exact same Guix}, with access to
4180 the @emph{exact same packages}. The output of @command{guix build gimp} on
4181 one machine will be exactly the same, bit for bit, as the output of the same
4182 command on the other machine. It also means both machines have access to all
4183 the source code of Guix and, transitively, to all the source code of every
4186 This gives you super powers, allowing you to track the provenance of binary
4187 artifacts with very fine grain, and to reproduce software environments at
4188 will---some sort of ``meta reproducibility'' capabilities, if you will.
4189 @xref{Inferiors}, for another way to take advantage of these super powers.
4191 @node Invoking guix time-machine
4192 @section Invoking @command{guix time-machine}
4194 @cindex @command{guix time-machine}
4195 @cindex pinning, channels
4196 @cindex replicating Guix
4197 @cindex reproducibility, of Guix
4199 The @command{guix time-machine} command provides access to other
4200 revisions of Guix, for example to install older versions of packages,
4201 or to reproduce a computation in an identical environment. The revision
4202 of Guix to be used is defined by a commit or by a channel
4203 description file created by @command{guix describe}
4204 (@pxref{Invoking guix describe}).
4206 The general syntax is:
4209 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4212 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4213 @command{guix} command if the specified revision. The @var{options} that define
4214 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4217 @item --url=@var{url}
4218 @itemx --commit=@var{commit}
4219 @itemx --branch=@var{branch}
4220 Use the @code{guix} channel from the specified @var{url}, at the
4221 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4222 string), or @var{branch}.
4224 @item --channels=@var{file}
4225 @itemx -C @var{file}
4226 Read the list of channels from @var{file}. @var{file} must contain
4227 Scheme code that evaluates to a list of channel objects.
4228 @xref{Channels} for more information.
4231 As for @command{guix pull}, the absence of any options means that the
4232 the latest commit on the master branch will be used. The command
4235 guix time-machine -- build hello
4238 will thus build the package @code{hello} as defined in the master branch,
4239 which is in general a newer revison of Guix than you have installed.
4240 Time travel works in both directions!
4242 Note that @command{guix time-machine} can trigger builds of channels and
4243 their dependencies, and these are controlled by the standard build
4244 options (@pxref{Common Build Options}).
4249 @c TODO: Remove this once we're more confident about API stability.
4251 The functionality described here is a ``technology preview'' as of version
4252 @value{VERSION}. As such, the interface is subject to change.
4256 @cindex composition of Guix revisions
4257 Sometimes you might need to mix packages from the revision of Guix you're
4258 currently running with packages available in a different revision of Guix.
4259 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4260 revisions in arbitrary ways.
4262 @cindex inferior packages
4263 Technically, an ``inferior'' is essentially a separate Guix process connected
4264 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4265 @code{(guix inferior)} module allows you to create inferiors and to
4266 communicate with them. It also provides a high-level interface to browse and
4267 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4269 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4270 to interact with a separate revision of Guix. For example, let's assume you
4271 want to install in your profile the current @code{guile} package, along with
4272 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4273 because the newer @code{guile-json} has an incompatible API and you want to
4274 run your code against the old API@. To do that, you could write a manifest for
4275 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4276 manifest, you would create an inferior for that old Guix revision you care
4277 about, and you would look up the @code{guile-json} package in the inferior:
4280 (use-modules (guix inferior) (guix channels)
4281 (srfi srfi-1)) ;for 'first'
4284 ;; This is the old revision from which we want to
4285 ;; extract guile-json.
4288 (url "https://git.savannah.gnu.org/git/guix.git")
4290 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4293 ;; An inferior representing the above revision.
4294 (inferior-for-channels channels))
4296 ;; Now create a manifest with the current "guile" package
4297 ;; and the old "guile-json" package.
4299 (list (first (lookup-inferior-packages inferior "guile-json"))
4300 (specification->package "guile")))
4303 On its first run, @command{guix package --manifest} might have to build the
4304 channel you specified before it can create the inferior; subsequent runs will
4305 be much faster because the Guix revision will be cached.
4307 The @code{(guix inferior)} module provides the following procedures to open an
4310 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4311 [#:cache-directory] [#:ttl]
4312 Return an inferior for @var{channels}, a list of channels. Use the cache at
4313 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4314 This procedure opens a new connection to the build daemon.
4316 As a side effect, this procedure may build or substitute binaries for
4317 @var{channels}, which can take time.
4320 @deffn {Scheme Procedure} open-inferior @var{directory} @
4321 [#:command "bin/guix"]
4322 Open the inferior Guix in @var{directory}, running
4323 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4324 the inferior could not be launched.
4327 @cindex inferior packages
4328 The procedures listed below allow you to obtain and manipulate inferior
4331 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4332 Return the list of packages known to @var{inferior}.
4335 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4337 Return the sorted list of inferior packages matching @var{name} in
4338 @var{inferior}, with highest version numbers first. If @var{version} is true,
4339 return only packages with a version number prefixed by @var{version}.
4342 @deffn {Scheme Procedure} inferior-package? @var{obj}
4343 Return true if @var{obj} is an inferior package.
4346 @deffn {Scheme Procedure} inferior-package-name @var{package}
4347 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4348 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4349 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4350 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4351 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4352 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4353 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4354 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4355 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4356 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4357 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4358 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4359 These procedures are the counterpart of package record accessors
4360 (@pxref{package Reference}). Most of them work by querying the inferior
4361 @var{package} comes from, so the inferior must still be live when you call
4365 Inferior packages can be used transparently like any other package or
4366 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4367 transparently handled by the @code{packages->manifest} procedure, which is
4368 commonly use in manifests (@pxref{Invoking guix package, the
4369 @option{--manifest} option of @command{guix package}}). Thus you can insert
4370 an inferior package pretty much anywhere you would insert a regular package:
4371 in manifests, in the @code{packages} field of your @code{operating-system}
4372 declaration, and so on.
4374 @node Invoking guix describe
4375 @section Invoking @command{guix describe}
4377 @cindex reproducibility
4378 @cindex replicating Guix
4379 Often you may want to answer questions like: ``Which revision of Guix am I
4380 using?'' or ``Which channels am I using?'' This is useful information in many
4381 situations: if you want to @emph{replicate} an environment on a different
4382 machine or user account, if you want to report a bug or to determine what
4383 change in the channels you are using caused it, or if you want to record your
4384 system state for reproducibility purposes. The @command{guix describe}
4385 command answers these questions.
4387 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4388 displays the channel(s) that it was built from, including their repository URL
4389 and commit IDs (@pxref{Channels}):
4393 Generation 10 Sep 03 2018 17:32:44 (current)
4395 repository URL: https://git.savannah.gnu.org/git/guix.git
4397 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4400 If you're familiar with the Git version control system, this is similar in
4401 spirit to @command{git describe}; the output is also similar to that of
4402 @command{guix pull --list-generations}, but limited to the current generation
4403 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4404 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4405 information is all it takes to describe the revision of Guix you're using, and
4406 also to replicate it.
4408 To make it easier to replicate Guix, @command{guix describe} can also be asked
4409 to return a list of channels instead of the human-readable description above:
4412 $ guix describe -f channels
4415 (url "https://git.savannah.gnu.org/git/guix.git")
4417 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4421 You can save this to a file and feed it to @command{guix pull -C} on some
4422 other machine or at a later point in time, which will instantiate @emph{this
4423 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4424 From there on, since you're able to deploy the same revision of Guix, you can
4425 just as well @emph{replicate a complete software environment}. We humbly
4426 think that this is @emph{awesome}, and we hope you'll like it too!
4428 The details of the options supported by @command{guix describe} are as
4432 @item --format=@var{format}
4433 @itemx -f @var{format}
4434 Produce output in the specified @var{format}, one of:
4438 produce human-readable output;
4440 produce a list of channel specifications that can be passed to @command{guix
4441 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4445 produce a list of channel specifications in JSON format;
4447 produce a list of channel specifications in Recutils format.
4450 @item --profile=@var{profile}
4451 @itemx -p @var{profile}
4452 Display information about @var{profile}.
4455 @node Invoking guix archive
4456 @section Invoking @command{guix archive}
4458 @cindex @command{guix archive}
4460 The @command{guix archive} command allows users to @dfn{export} files
4461 from the store into a single archive, and to later @dfn{import} them on
4462 a machine that runs Guix.
4463 In particular, it allows store files to be transferred from one machine
4464 to the store on another machine.
4467 If you're looking for a way to produce archives in a format suitable for
4468 tools other than Guix, @pxref{Invoking guix pack}.
4471 @cindex exporting store items
4472 To export store files as an archive to standard output, run:
4475 guix archive --export @var{options} @var{specifications}...
4478 @var{specifications} may be either store file names or package
4479 specifications, as for @command{guix package} (@pxref{Invoking guix
4480 package}). For instance, the following command creates an archive
4481 containing the @code{gui} output of the @code{git} package and the main
4482 output of @code{emacs}:
4485 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4488 If the specified packages are not built yet, @command{guix archive}
4489 automatically builds them. The build process may be controlled with the
4490 common build options (@pxref{Common Build Options}).
4492 To transfer the @code{emacs} package to a machine connected over SSH,
4496 guix archive --export -r emacs | ssh the-machine guix archive --import
4500 Similarly, a complete user profile may be transferred from one machine
4501 to another like this:
4504 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4505 ssh the-machine guix archive --import
4509 However, note that, in both examples, all of @code{emacs} and the
4510 profile as well as all of their dependencies are transferred (due to
4511 @code{-r}), regardless of what is already available in the store on the
4512 target machine. The @code{--missing} option can help figure out which
4513 items are missing from the target store. The @command{guix copy}
4514 command simplifies and optimizes this whole process, so this is probably
4515 what you should use in this case (@pxref{Invoking guix copy}).
4517 @cindex nar, archive format
4518 @cindex normalized archive (nar)
4519 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4520 comparable in spirit to `tar', but with differences
4521 that make it more appropriate for our purposes. First, rather than
4522 recording all Unix metadata for each file, the nar format only mentions
4523 the file type (regular, directory, or symbolic link); Unix permissions
4524 and owner/group are dismissed. Second, the order in which directory
4525 entries are stored always follows the order of file names according to
4526 the C locale collation order. This makes archive production fully
4529 When exporting, the daemon digitally signs the contents of the archive,
4530 and that digital signature is appended. When importing, the daemon
4531 verifies the signature and rejects the import in case of an invalid
4532 signature or if the signing key is not authorized.
4533 @c FIXME: Add xref to daemon doc about signatures.
4535 The main options are:
4539 Export the specified store files or packages (see below.) Write the
4540 resulting archive to the standard output.
4542 Dependencies are @emph{not} included in the output, unless
4543 @code{--recursive} is passed.
4547 When combined with @code{--export}, this instructs @command{guix
4548 archive} to include dependencies of the given items in the archive.
4549 Thus, the resulting archive is self-contained: it contains the closure
4550 of the exported store items.
4553 Read an archive from the standard input, and import the files listed
4554 therein into the store. Abort if the archive has an invalid digital
4555 signature, or if it is signed by a public key not among the authorized
4556 keys (see @code{--authorize} below.)
4559 Read a list of store file names from the standard input, one per line,
4560 and write on the standard output the subset of these files missing from
4563 @item --generate-key[=@var{parameters}]
4564 @cindex signing, archives
4565 Generate a new key pair for the daemon. This is a prerequisite before
4566 archives can be exported with @code{--export}. Note that this operation
4567 usually takes time, because it needs to gather enough entropy to
4568 generate the key pair.
4570 The generated key pair is typically stored under @file{/etc/guix}, in
4571 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4572 key, which must be kept secret.) When @var{parameters} is omitted,
4573 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4574 versions before 1.6.0, it is a 4096-bit RSA key.
4575 Alternatively, @var{parameters} can specify
4576 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4577 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4578 Libgcrypt Reference Manual}).
4581 @cindex authorizing, archives
4582 Authorize imports signed by the public key passed on standard input.
4583 The public key must be in ``s-expression advanced format''---i.e., the
4584 same format as the @file{signing-key.pub} file.
4586 The list of authorized keys is kept in the human-editable file
4587 @file{/etc/guix/acl}. The file contains
4588 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4589 s-expressions''} and is structured as an access-control list in the
4590 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4593 @item --extract=@var{directory}
4594 @itemx -x @var{directory}
4595 Read a single-item archive as served by substitute servers
4596 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4597 low-level operation needed in only very narrow use cases; see below.
4599 For example, the following command extracts the substitute for Emacs
4600 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4604 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-emacs-24.5 \
4605 | bunzip2 | guix archive -x /tmp/emacs
4608 Single-item archives are different from multiple-item archives produced
4609 by @command{guix archive --export}; they contain a single store item,
4610 and they do @emph{not} embed a signature. Thus this operation does
4611 @emph{no} signature verification and its output should be considered
4614 The primary purpose of this operation is to facilitate inspection of
4615 archive contents coming from possibly untrusted substitute servers.
4619 Read a single-item archive as served by substitute servers
4620 (@pxref{Substitutes}) and print the list of files it contains, as in
4625 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4626 | lzip -d | guix archive -t
4632 @c *********************************************************************
4634 @chapter Development
4636 @cindex software development
4637 If you are a software developer, Guix provides tools that you should find
4638 helpful---independently of the language you're developing in. This is what
4639 this chapter is about.
4641 The @command{guix environment} command provides a convenient way to set up
4642 @dfn{development environments} containing all the dependencies and tools
4643 necessary to work on the software package of your choice. The @command{guix
4644 pack} command allows you to create @dfn{application bundles} that can be
4645 easily distributed to users who do not run Guix.
4648 * Invoking guix environment:: Setting up development environments.
4649 * Invoking guix pack:: Creating software bundles.
4652 @node Invoking guix environment
4653 @section Invoking @command{guix environment}
4655 @cindex reproducible build environments
4656 @cindex development environments
4657 @cindex @command{guix environment}
4658 @cindex environment, package build environment
4659 The purpose of @command{guix environment} is to assist hackers in
4660 creating reproducible development environments without polluting their
4661 package profile. The @command{guix environment} tool takes one or more
4662 packages, builds all of their inputs, and creates a shell
4663 environment to use them.
4665 The general syntax is:
4668 guix environment @var{options} @var{package}@dots{}
4671 The following example spawns a new shell set up for the development of
4675 guix environment guile
4678 If the needed dependencies are not built yet, @command{guix environment}
4679 automatically builds them. The environment of the new shell is an augmented
4680 version of the environment that @command{guix environment} was run in.
4681 It contains the necessary search paths for building the given package
4682 added to the existing environment variables. To create a ``pure''
4683 environment, in which the original environment variables have been unset,
4684 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4685 environment variables such as @code{PATH} in their @file{~/.bashrc}
4686 file. As a consequence, when @code{guix environment} launches it, Bash
4687 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4688 environment variables. It is an error to define such environment
4689 variables in @file{.bashrc}; instead, they should be defined in
4690 @file{.bash_profile}, which is sourced only by log-in shells.
4691 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4692 details on Bash start-up files.}.
4694 @vindex GUIX_ENVIRONMENT
4695 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4696 variable in the shell it spawns; its value is the file name of the
4697 profile of this environment. This allows users to, say, define a
4698 specific prompt for development environments in their @file{.bashrc}
4699 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4702 if [ -n "$GUIX_ENVIRONMENT" ]
4704 export PS1="\u@@\h \w [dev]\$ "
4709 ...@: or to browse the profile:
4712 $ ls "$GUIX_ENVIRONMENT/bin"
4715 Additionally, more than one package may be specified, in which case the
4716 union of the inputs for the given packages are used. For example, the
4717 command below spawns a shell where all of the dependencies of both Guile
4718 and Emacs are available:
4721 guix environment guile emacs
4724 Sometimes an interactive shell session is not desired. An arbitrary
4725 command may be invoked by placing the @code{--} token to separate the
4726 command from the rest of the arguments:
4729 guix environment guile -- make -j4
4732 In other situations, it is more convenient to specify the list of
4733 packages needed in the environment. For example, the following command
4734 runs @command{python} from an environment containing Python@tie{}2.7 and
4738 guix environment --ad-hoc python2-numpy python-2.7 -- python
4741 Furthermore, one might want the dependencies of a package and also some
4742 additional packages that are not build-time or runtime dependencies, but
4743 are useful when developing nonetheless. Because of this, the
4744 @code{--ad-hoc} flag is positional. Packages appearing before
4745 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4746 added to the environment. Packages appearing after are interpreted as
4747 packages that will be added to the environment directly. For example,
4748 the following command creates a Guix development environment that
4749 additionally includes Git and strace:
4752 guix environment guix --ad-hoc git strace
4755 Sometimes it is desirable to isolate the environment as much as
4756 possible, for maximal purity and reproducibility. In particular, when
4757 using Guix on a host distro that is not Guix System, it is desirable to
4758 prevent access to @file{/usr/bin} and other system-wide resources from
4759 the development environment. For example, the following command spawns
4760 a Guile REPL in a ``container'' where only the store and the current
4761 working directory are mounted:
4764 guix environment --ad-hoc --container guile -- guile
4768 The @code{--container} option requires Linux-libre 3.19 or newer.
4771 The available options are summarized below.
4774 @item --root=@var{file}
4775 @itemx -r @var{file}
4776 @cindex persistent environment
4777 @cindex garbage collector root, for environments
4778 Make @var{file} a symlink to the profile for this environment, and
4779 register it as a garbage collector root.
4781 This is useful if you want to protect your environment from garbage
4782 collection, to make it ``persistent''.
4784 When this option is omitted, the environment is protected from garbage
4785 collection only for the duration of the @command{guix environment}
4786 session. This means that next time you recreate the same environment,
4787 you could have to rebuild or re-download packages. @xref{Invoking guix
4788 gc}, for more on GC roots.
4790 @item --expression=@var{expr}
4791 @itemx -e @var{expr}
4792 Create an environment for the package or list of packages that
4793 @var{expr} evaluates to.
4795 For example, running:
4798 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4801 starts a shell with the environment for this specific variant of the
4807 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4810 starts a shell with all the base system packages available.
4812 The above commands only use the default output of the given packages.
4813 To select other outputs, two element tuples can be specified:
4816 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4819 @item --load=@var{file}
4820 @itemx -l @var{file}
4821 Create an environment for the package or list of packages that the code
4822 within @var{file} evaluates to.
4824 As an example, @var{file} might contain a definition like this
4825 (@pxref{Defining Packages}):
4828 @verbatiminclude environment-gdb.scm
4831 @item --manifest=@var{file}
4832 @itemx -m @var{file}
4833 Create an environment for the packages contained in the manifest object
4834 returned by the Scheme code in @var{file}. This option can be repeated
4835 several times, in which case the manifests are concatenated.
4837 This is similar to the same-named option in @command{guix package}
4838 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4842 Include all specified packages in the resulting environment, as if an
4843 @i{ad hoc} package were defined with them as inputs. This option is
4844 useful for quickly creating an environment without having to write a
4845 package expression to contain the desired inputs.
4847 For instance, the command:
4850 guix environment --ad-hoc guile guile-sdl -- guile
4853 runs @command{guile} in an environment where Guile and Guile-SDL are
4856 Note that this example implicitly asks for the default output of
4857 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4858 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4859 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4861 This option may be composed with the default behavior of @command{guix
4862 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4863 as packages whose dependencies will be added to the environment, the
4864 default behavior. Packages appearing after are interpreted as packages
4865 that will be added to the environment directly.
4868 Unset existing environment variables when building the new environment, except
4869 those specified with @option{--preserve} (see below.) This has the effect of
4870 creating an environment in which search paths only contain package inputs.
4872 @item --preserve=@var{regexp}
4873 @itemx -E @var{regexp}
4874 When used alongside @option{--pure}, preserve the environment variables
4875 matching @var{regexp}---in other words, put them on a ``white list'' of
4876 environment variables that must be preserved. This option can be repeated
4880 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4884 This example runs @command{mpirun} in a context where the only environment
4885 variables defined are @code{PATH}, environment variables whose name starts
4886 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4889 @item --search-paths
4890 Display the environment variable definitions that make up the
4893 @item --system=@var{system}
4894 @itemx -s @var{system}
4895 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4900 Run @var{command} within an isolated container. The current working
4901 directory outside the container is mapped inside the container.
4902 Additionally, unless overridden with @code{--user}, a dummy home
4903 directory is created that matches the current user's home directory, and
4904 @file{/etc/passwd} is configured accordingly.
4906 The spawned process runs as the current user outside the container. Inside
4907 the container, it has the same UID and GID as the current user, unless
4908 @option{--user} is passed (see below.)
4912 For containers, share the network namespace with the host system.
4913 Containers created without this flag only have access to the loopback
4916 @item --link-profile
4918 For containers, link the environment profile to
4919 @file{~/.guix-profile} within the container. This is equivalent to
4920 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4921 within the container. Linking will fail and abort the environment if
4922 the directory already exists, which will certainly be the case if
4923 @command{guix environment} was invoked in the user's home directory.
4925 Certain packages are configured to look in
4926 @code{~/.guix-profile} for configuration files and data;@footnote{For
4927 example, the @code{fontconfig} package inspects
4928 @file{~/.guix-profile/share/fonts} for additional fonts.}
4929 @code{--link-profile} allows these programs to behave as expected within
4932 @item --user=@var{user}
4933 @itemx -u @var{user}
4934 For containers, use the username @var{user} in place of the current
4935 user. The generated @file{/etc/passwd} entry within the container will
4936 contain the name @var{user}, the home directory will be
4937 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4938 the UID and GID inside the container are 1000. @var{user}
4939 need not exist on the system.
4941 Additionally, any shared or exposed path (see @code{--share} and
4942 @code{--expose} respectively) whose target is within the current user's
4943 home directory will be remapped relative to @file{/home/USER}; this
4944 includes the automatic mapping of the current working directory.
4947 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4949 guix environment --container --user=foo \
4950 --expose=$HOME/test \
4951 --expose=/tmp/target=$HOME/target
4954 While this will limit the leaking of user identity through home paths
4955 and each of the user fields, this is only one useful component of a
4956 broader privacy/anonymity solution---not one in and of itself.
4959 For containers, the default behavior is to share the current working
4960 directory with the isolated container and immediately change to that
4961 directory within the container. If this is undesirable, @code{--no-cwd}
4962 will cause the current working directory to @emph{not} be automatically
4963 shared and will change to the user's home directory within the container
4964 instead. See also @code{--user}.
4966 @item --expose=@var{source}[=@var{target}]
4967 @itemx --share=@var{source}[=@var{target}]
4968 For containers, @code{--expose} (resp. @code{--share}) exposes the file
4969 system @var{source} from the host system as the read-only
4970 (resp. writable) file system @var{target} within the container. If
4971 @var{target} is not specified, @var{source} is used as the target mount
4972 point in the container.
4974 The example below spawns a Guile REPL in a container in which the user's
4975 home directory is accessible read-only via the @file{/exchange}
4979 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
4984 @command{guix environment}
4985 also supports all of the common build options that @command{guix
4986 build} supports (@pxref{Common Build Options}) as well as package
4987 transformation options (@pxref{Package Transformation Options}).
4989 @node Invoking guix pack
4990 @section Invoking @command{guix pack}
4992 Occasionally you want to pass software to people who are not (yet!)
4993 lucky enough to be using Guix. You'd tell them to run @command{guix
4994 package -i @var{something}}, but that's not possible in this case. This
4995 is where @command{guix pack} comes in.
4998 If you are looking for ways to exchange binaries among machines that
4999 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5000 publish}, and @ref{Invoking guix archive}.
5005 @cindex application bundle
5006 @cindex software bundle
5007 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5008 @dfn{software bundle}: it creates a tarball or some other archive
5009 containing the binaries of the software you're interested in, and all
5010 its dependencies. The resulting archive can be used on any machine that
5011 does not have Guix, and people can run the exact same binaries as those
5012 you have with Guix. The pack itself is created in a bit-reproducible
5013 fashion, so anyone can verify that it really contains the build results
5014 that you pretend to be shipping.
5016 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5017 their dependencies, you can run:
5020 $ guix pack guile emacs geiser
5022 /gnu/store/@dots{}-pack.tar.gz
5025 The result here is a tarball containing a @file{/gnu/store} directory
5026 with all the relevant packages. The resulting tarball contains a
5027 @dfn{profile} with the three packages of interest; the profile is the
5028 same as would be created by @command{guix package -i}. It is this
5029 mechanism that is used to create Guix's own standalone binary tarball
5030 (@pxref{Binary Installation}).
5032 Users of this pack would have to run
5033 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5034 find inconvenient. To work around it, you can create, say, a
5035 @file{/opt/gnu/bin} symlink to the profile:
5038 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5042 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5044 @cindex relocatable binaries, with @command{guix pack}
5045 What if the recipient of your pack does not have root privileges on
5046 their machine, and thus cannot unpack it in the root file system? In
5047 that case, you will want to use the @code{--relocatable} option (see
5048 below). This option produces @dfn{relocatable binaries}, meaning they
5049 they can be placed anywhere in the file system hierarchy: in the example
5050 above, users can unpack your tarball in their home directory and
5051 directly run @file{./opt/gnu/bin/guile}.
5053 @cindex Docker, build an image with guix pack
5054 Alternatively, you can produce a pack in the Docker image format using
5055 the following command:
5058 guix pack -f docker -S /bin=bin guile guile-readline
5062 The result is a tarball that can be passed to the @command{docker load}
5063 command, followed by @code{docker run}:
5066 docker load < @var{file}
5067 docker run -ti guile-guile-readline /bin/guile
5071 where @var{file} is the image returned by @var{guix pack}, and
5072 @code{guile-guile-readline} is its ``image tag''. See the
5073 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5074 documentation} for more information.
5076 @cindex Singularity, build an image with guix pack
5077 @cindex SquashFS, build an image with guix pack
5078 Yet another option is to produce a SquashFS image with the following
5082 guix pack -f squashfs bash guile emacs geiser
5086 The result is a SquashFS file system image that can either be mounted or
5087 directly be used as a file system container image with the
5088 @uref{https://singularity.lbl.gov, Singularity container execution
5089 environment}, using commands like @command{singularity shell} or
5090 @command{singularity exec}.
5092 Several command-line options allow you to customize your pack:
5095 @item --format=@var{format}
5096 @itemx -f @var{format}
5097 Produce a pack in the given @var{format}.
5099 The available formats are:
5103 This is the default format. It produces a tarball containing all the
5104 specified binaries and symlinks.
5107 This produces a tarball that follows the
5108 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5109 Docker Image Specification}. The ``repository name'' as it appears in
5110 the output of the @command{docker images} command is computed from
5111 package names passed on the command line or in the manifest file.
5114 This produces a SquashFS image containing all the specified binaries and
5115 symlinks, as well as empty mount points for virtual file systems like
5119 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5120 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5121 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5122 with something like:
5125 guix pack -f squashfs bash @dots{}
5128 If you forget the @code{bash} (or similar) package, @command{singularity
5129 run} and @command{singularity exec} will fail with an unhelpful ``no
5130 such file or directory'' message.
5134 @cindex relocatable binaries
5137 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5138 anywhere in the file system hierarchy and run from there.
5140 When this option is passed once, the resulting binaries require support for
5141 @dfn{user namespaces} in the kernel Linux; when passed
5142 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5143 PRoot support, can be thought of as the abbreviation of ``Really
5144 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
5145 if user namespaces are unavailable, and essentially work anywhere---see below
5146 for the implications.
5148 For example, if you create a pack containing Bash with:
5151 guix pack -RR -S /mybin=bin bash
5155 ...@: you can copy that pack to a machine that lacks Guix, and from your
5156 home directory as a normal user, run:
5164 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5165 @file{/gnu/store} shows up and contains all the dependencies of
5166 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5167 altogether! That is probably the simplest way to deploy Guix-built
5168 software on a non-Guix machine.
5171 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5172 the kernel Linux, which allows unprivileged users to mount or change root.
5173 Old versions of Linux did not support it, and some GNU/Linux distributions
5176 To produce relocatable binaries that work even in the absence of user
5177 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5178 case, binaries will try user namespace support and fall back to PRoot if user
5179 namespaces are not supported.
5181 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
5182 support for file system virtualization. It achieves that by using the
5183 @code{ptrace} system call on the running program. This approach has the
5184 advantage to work without requiring special kernel support, but it incurs
5185 run-time overhead every time a system call is made.
5188 @cindex entry point, for Docker images
5189 @item --entry-point=@var{command}
5190 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5191 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5192 support it. @var{command} must be relative to the profile contained in the
5195 The entry point specifies the command that tools like @code{docker run} or
5196 @code{singularity run} automatically start by default. For example, you can
5200 guix pack -f docker --entry-point=bin/guile guile
5203 The resulting pack can easily be loaded and @code{docker run} with no extra
5204 arguments will spawn @code{bin/guile}:
5207 docker load -i pack.tar.gz
5208 docker run @var{image-id}
5211 @item --expression=@var{expr}
5212 @itemx -e @var{expr}
5213 Consider the package @var{expr} evaluates to.
5215 This has the same purpose as the same-named option in @command{guix
5216 build} (@pxref{Additional Build Options, @code{--expression} in
5217 @command{guix build}}).
5219 @item --manifest=@var{file}
5220 @itemx -m @var{file}
5221 Use the packages contained in the manifest object returned by the Scheme
5222 code in @var{file}. This option can be repeated several times, in which
5223 case the manifests are concatenated.
5225 This has a similar purpose as the same-named option in @command{guix
5226 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5227 same manifest files. It allows you to define a collection of packages
5228 once and use it both for creating profiles and for creating archives
5229 for use on machines that do not have Guix installed. Note that you can
5230 specify @emph{either} a manifest file @emph{or} a list of packages,
5233 @item --system=@var{system}
5234 @itemx -s @var{system}
5235 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5236 the system type of the build host.
5238 @item --target=@var{triplet}
5239 @cindex cross-compilation
5240 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5241 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
5242 configuration triplets,, autoconf, Autoconf}).
5244 @item --compression=@var{tool}
5245 @itemx -C @var{tool}
5246 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5247 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
5249 @item --symlink=@var{spec}
5250 @itemx -S @var{spec}
5251 Add the symlinks specified by @var{spec} to the pack. This option can
5252 appear several times.
5254 @var{spec} has the form @code{@var{source}=@var{target}}, where
5255 @var{source} is the symlink that will be created and @var{target} is the
5258 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5259 symlink pointing to the @file{bin} sub-directory of the profile.
5261 @item --save-provenance
5262 Save provenance information for the packages passed on the command line.
5263 Provenance information includes the URL and commit of the channels in use
5266 Provenance information is saved in the
5267 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5268 usual package metadata---the name and version of each package, their
5269 propagated inputs, and so on. It is useful information to the recipient of
5270 the pack, who then knows how the pack was (supposedly) obtained.
5272 This option is not enabled by default because, like timestamps, provenance
5273 information contributes nothing to the build process. In other words, there
5274 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5275 Recording such ``silent'' metadata in the output thus potentially breaks the
5276 source-to-binary bitwise reproducibility property.
5278 @item --root=@var{file}
5279 @itemx -r @var{file}
5280 @cindex garbage collector root, for packs
5281 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5284 @item --localstatedir
5285 @itemx --profile-name=@var{name}
5286 Include the ``local state directory'', @file{/var/guix}, in the resulting
5287 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5288 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5289 @file{~root/.guix-profile}.
5291 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5292 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5293 the pack means that the store is ``complete'' and manageable by Guix;
5294 not providing it pack means that the store is ``dead'': items cannot be
5295 added to it or removed from it after extraction of the pack.
5297 One use case for this is the Guix self-contained binary tarball
5298 (@pxref{Binary Installation}).
5302 Print the name of the derivation that builds the pack.
5305 Use the bootstrap binaries to build the pack. This option is only
5306 useful to Guix developers.
5309 In addition, @command{guix pack} supports all the common build options
5310 (@pxref{Common Build Options}) and all the package transformation
5311 options (@pxref{Package Transformation Options}).
5314 @c *********************************************************************
5315 @node Programming Interface
5316 @chapter Programming Interface
5318 GNU Guix provides several Scheme programming interfaces (APIs) to
5319 define, build, and query packages. The first interface allows users to
5320 write high-level package definitions. These definitions refer to
5321 familiar packaging concepts, such as the name and version of a package,
5322 its build system, and its dependencies. These definitions can then be
5323 turned into concrete build actions.
5325 Build actions are performed by the Guix daemon, on behalf of users. In a
5326 standard setup, the daemon has write access to the store---the
5327 @file{/gnu/store} directory---whereas users do not. The recommended
5328 setup also has the daemon perform builds in chroots, under a specific
5329 build users, to minimize interference with the rest of the system.
5332 Lower-level APIs are available to interact with the daemon and the
5333 store. To instruct the daemon to perform a build action, users actually
5334 provide it with a @dfn{derivation}. A derivation is a low-level
5335 representation of the build actions to be taken, and the environment in
5336 which they should occur---derivations are to package definitions what
5337 assembly is to C programs. The term ``derivation'' comes from the fact
5338 that build results @emph{derive} from them.
5340 This chapter describes all these APIs in turn, starting from high-level
5341 package definitions.
5344 * Package Modules:: Packages from the programmer's viewpoint.
5345 * Defining Packages:: Defining new packages.
5346 * Build Systems:: Specifying how packages are built.
5347 * The Store:: Manipulating the package store.
5348 * Derivations:: Low-level interface to package derivations.
5349 * The Store Monad:: Purely functional interface to the store.
5350 * G-Expressions:: Manipulating build expressions.
5351 * Invoking guix repl:: Fiddling with Guix interactively.
5354 @node Package Modules
5355 @section Package Modules
5357 From a programming viewpoint, the package definitions of the
5358 GNU distribution are provided by Guile modules in the @code{(gnu packages
5359 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5360 packages @dots{})} module name space are not necessarily ``GNU
5361 packages''. This module naming scheme follows the usual Guile module
5362 naming convention: @code{gnu} means that these modules are distributed
5363 as part of the GNU system, and @code{packages} identifies modules that
5364 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5365 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5366 module exports a variable named @code{emacs}, which is bound to a
5367 @code{<package>} object (@pxref{Defining Packages}).
5369 The @code{(gnu packages @dots{})} module name space is
5370 automatically scanned for packages by the command-line tools. For
5371 instance, when running @code{guix install emacs}, all the @code{(gnu
5372 packages @dots{})} modules are scanned until one that exports a package
5373 object whose name is @code{emacs} is found. This package search
5374 facility is implemented in the @code{(gnu packages)} module.
5376 @cindex customization, of packages
5377 @cindex package module search path
5378 Users can store package definitions in modules with different
5379 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5380 name and module name must match. For instance, the @code{(my-packages
5381 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5382 relative to the load path specified with @option{--load-path} or
5383 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5384 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5385 these package definitions visible to the user interfaces:
5389 By adding the directory containing your package modules to the search path
5390 with the @code{-L} flag of @command{guix package} and other commands
5391 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5392 environment variable described below.
5395 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5396 pulls from it. A channel is essentially a Git repository containing package
5397 modules. @xref{Channels}, for more information on how to define and use
5401 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5403 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5404 This is a colon-separated list of directories to search for additional
5405 package modules. Directories listed in this variable take precedence
5406 over the own modules of the distribution.
5409 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5410 each package is built based solely on other packages in the
5411 distribution. The root of this dependency graph is a small set of
5412 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5413 bootstrap)} module. For more information on bootstrapping,
5414 @pxref{Bootstrapping}.
5416 @node Defining Packages
5417 @section Defining Packages
5419 The high-level interface to package definitions is implemented in the
5420 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5421 example, the package definition, or @dfn{recipe}, for the GNU Hello
5422 package looks like this:
5425 (define-module (gnu packages hello)
5426 #:use-module (guix packages)
5427 #:use-module (guix download)
5428 #:use-module (guix build-system gnu)
5429 #:use-module (guix licenses)
5430 #:use-module (gnu packages gawk))
5432 (define-public hello
5438 (uri (string-append "mirror://gnu/hello/hello-" version
5442 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5443 (build-system gnu-build-system)
5444 (arguments '(#:configure-flags '("--enable-silent-rules")))
5445 (inputs `(("gawk" ,gawk)))
5446 (synopsis "Hello, GNU world: An example GNU package")
5447 (description "Guess what GNU Hello prints!")
5448 (home-page "https://www.gnu.org/software/hello/")
5453 Without being a Scheme expert, the reader may have guessed the meaning
5454 of the various fields here. This expression binds the variable
5455 @code{hello} to a @code{<package>} object, which is essentially a record
5456 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5457 This package object can be inspected using procedures found in the
5458 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5459 returns---surprise!---@code{"hello"}.
5461 With luck, you may be able to import part or all of the definition of
5462 the package you are interested in from another repository, using the
5463 @code{guix import} command (@pxref{Invoking guix import}).
5465 In the example above, @var{hello} is defined in a module of its own,
5466 @code{(gnu packages hello)}. Technically, this is not strictly
5467 necessary, but it is convenient to do so: all the packages defined in
5468 modules under @code{(gnu packages @dots{})} are automatically known to
5469 the command-line tools (@pxref{Package Modules}).
5471 There are a few points worth noting in the above package definition:
5475 The @code{source} field of the package is an @code{<origin>} object
5476 (@pxref{origin Reference}, for the complete reference).
5477 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5478 meaning that the source is a file to be downloaded over FTP or HTTP.
5480 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5481 the GNU mirrors defined in @code{(guix download)}.
5483 The @code{sha256} field specifies the expected SHA256 hash of the file
5484 being downloaded. It is mandatory, and allows Guix to check the
5485 integrity of the file. The @code{(base32 @dots{})} form introduces the
5486 base32 representation of the hash. You can obtain this information with
5487 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5488 hash} (@pxref{Invoking guix hash}).
5491 When needed, the @code{origin} form can also have a @code{patches} field
5492 listing patches to be applied, and a @code{snippet} field giving a
5493 Scheme expression to modify the source code.
5496 @cindex GNU Build System
5497 The @code{build-system} field specifies the procedure to build the
5498 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5499 represents the familiar GNU Build System, where packages may be
5500 configured, built, and installed with the usual @code{./configure &&
5501 make && make check && make install} command sequence.
5504 The @code{arguments} field specifies options for the build system
5505 (@pxref{Build Systems}). Here it is interpreted by
5506 @var{gnu-build-system} as a request run @file{configure} with the
5507 @code{--enable-silent-rules} flag.
5513 What about these quote (@code{'}) characters? They are Scheme syntax to
5514 introduce a literal list; @code{'} is synonymous with @code{quote}.
5515 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5516 for details. Here the value of the @code{arguments} field is a list of
5517 arguments passed to the build system down the road, as with @code{apply}
5518 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5521 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5522 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5523 @code{#:configure-flags} is a keyword used to pass a keyword argument
5524 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5528 The @code{inputs} field specifies inputs to the build process---i.e.,
5529 build-time or run-time dependencies of the package. Here, we define an
5530 input called @code{"gawk"} whose value is that of the @var{gawk}
5531 variable; @var{gawk} is itself bound to a @code{<package>} object.
5533 @cindex backquote (quasiquote)
5536 @cindex comma (unquote)
5540 @findex unquote-splicing
5541 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5542 us to introduce a literal list in the @code{inputs} field, while
5543 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5544 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5547 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5548 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5549 of ensuring that they are present (@pxref{Build Systems}).
5551 However, any other dependencies need to be specified in the
5552 @code{inputs} field. Any dependency not specified here will simply be
5553 unavailable to the build process, possibly leading to a build failure.
5556 @xref{package Reference}, for a full description of possible fields.
5558 Once a package definition is in place, the
5559 package may actually be built using the @code{guix build} command-line
5560 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5561 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5562 package definition using the @command{guix edit} command
5563 (@pxref{Invoking guix edit}).
5564 @xref{Packaging Guidelines}, for
5565 more information on how to test package definitions, and
5566 @ref{Invoking guix lint}, for information on how to check a definition
5567 for style conformance.
5568 @vindex GUIX_PACKAGE_PATH
5569 Lastly, @pxref{Channels}, for information
5570 on how to extend the distribution by adding your own package definitions
5573 Finally, updating the package definition to a new upstream version
5574 can be partly automated by the @command{guix refresh} command
5575 (@pxref{Invoking guix refresh}).
5577 Behind the scenes, a derivation corresponding to the @code{<package>}
5578 object is first computed by the @code{package-derivation} procedure.
5579 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5580 The build actions it prescribes may then be realized by using the
5581 @code{build-derivations} procedure (@pxref{The Store}).
5583 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5584 Return the @code{<derivation>} object of @var{package} for @var{system}
5585 (@pxref{Derivations}).
5587 @var{package} must be a valid @code{<package>} object, and @var{system}
5588 must be a string denoting the target system type---e.g.,
5589 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5590 must be a connection to the daemon, which operates on the store
5591 (@pxref{The Store}).
5595 @cindex cross-compilation
5596 Similarly, it is possible to compute a derivation that cross-builds a
5597 package for some other system:
5599 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5600 @var{package} @var{target} [@var{system}]
5601 Return the @code{<derivation>} object of @var{package} cross-built from
5602 @var{system} to @var{target}.
5604 @var{target} must be a valid GNU triplet denoting the target hardware
5605 and operating system, such as @code{"mips64el-linux-gnu"}
5606 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5609 @cindex package transformations
5610 @cindex input rewriting
5611 @cindex dependency tree rewriting
5612 Packages can be manipulated in arbitrary ways. An example of a useful
5613 transformation is @dfn{input rewriting}, whereby the dependency tree of
5614 a package is rewritten by replacing specific inputs by others:
5616 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5617 [@var{rewrite-name}]
5618 Return a procedure that, when passed a package, replaces its direct and
5619 indirect dependencies (but not its implicit inputs) according to
5620 @var{replacements}. @var{replacements} is a list of package pairs; the
5621 first element of each pair is the package to replace, and the second one
5624 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5625 the name of a package and returns its new name after rewrite.
5629 Consider this example:
5632 (define libressl-instead-of-openssl
5633 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5635 (package-input-rewriting `((,openssl . ,libressl))))
5637 (define git-with-libressl
5638 (libressl-instead-of-openssl git))
5642 Here we first define a rewriting procedure that replaces @var{openssl}
5643 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5644 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5645 This is exactly what the @option{--with-input} command-line option does
5646 (@pxref{Package Transformation Options, @option{--with-input}}).
5648 The following variant of @code{package-input-rewriting} can match packages to
5649 be replaced by name rather than by identity.
5651 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5652 Return a procedure that, given a package, applies the given @var{replacements} to
5653 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5654 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5655 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5656 replacement for that package.
5659 The example above could be rewritten this way:
5662 (define libressl-instead-of-openssl
5663 ;; Replace all the packages called "openssl" with LibreSSL.
5664 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5667 The key difference here is that, this time, packages are matched by spec and
5668 not by identity. In other words, any package in the graph that is called
5669 @code{openssl} will be replaced.
5671 A more generic procedure to rewrite a package dependency graph is
5672 @code{package-mapping}: it supports arbitrary changes to nodes in the
5675 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5676 Return a procedure that, given a package, applies @var{proc} to all the packages
5677 depended on and returns the resulting package. The procedure stops recursion
5678 when @var{cut?} returns true for a given package.
5682 * package Reference:: The package data type.
5683 * origin Reference:: The origin data type.
5687 @node package Reference
5688 @subsection @code{package} Reference
5690 This section summarizes all the options available in @code{package}
5691 declarations (@pxref{Defining Packages}).
5693 @deftp {Data Type} package
5694 This is the data type representing a package recipe.
5698 The name of the package, as a string.
5700 @item @code{version}
5701 The version of the package, as a string.
5704 An object telling how the source code for the package should be
5705 acquired. Most of the time, this is an @code{origin} object, which
5706 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5707 can also be any other ``file-like'' object such as a @code{local-file},
5708 which denotes a file from the local file system (@pxref{G-Expressions,
5709 @code{local-file}}).
5711 @item @code{build-system}
5712 The build system that should be used to build the package (@pxref{Build
5715 @item @code{arguments} (default: @code{'()})
5716 The arguments that should be passed to the build system. This is a
5717 list, typically containing sequential keyword-value pairs.
5719 @item @code{inputs} (default: @code{'()})
5720 @itemx @code{native-inputs} (default: @code{'()})
5721 @itemx @code{propagated-inputs} (default: @code{'()})
5722 @cindex inputs, of packages
5723 These fields list dependencies of the package. Each one is a list of
5724 tuples, where each tuple has a label for the input (a string) as its
5725 first element, a package, origin, or derivation as its second element,
5726 and optionally the name of the output thereof that should be used, which
5727 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5728 more on package outputs). For example, the list below specifies three
5732 `(("libffi" ,libffi)
5733 ("libunistring" ,libunistring)
5734 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5737 @cindex cross compilation, package dependencies
5738 The distinction between @code{native-inputs} and @code{inputs} is
5739 necessary when considering cross-compilation. When cross-compiling,
5740 dependencies listed in @code{inputs} are built for the @emph{target}
5741 architecture; conversely, dependencies listed in @code{native-inputs}
5742 are built for the architecture of the @emph{build} machine.
5744 @code{native-inputs} is typically used to list tools needed at
5745 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5746 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5747 this area (@pxref{Invoking guix lint}).
5749 @anchor{package-propagated-inputs}
5750 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5751 specified packages will be automatically installed alongside the package
5752 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5753 package}}, for information on how @command{guix package} deals with
5756 For example this is necessary when a C/C++ library needs headers of
5757 another library to compile, or when a pkg-config file refers to another
5758 one @i{via} its @code{Requires} field.
5760 Another example where @code{propagated-inputs} is useful is for languages
5761 that lack a facility to record the run-time search path akin to the
5762 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5763 more. To ensure that libraries written in those languages can find
5764 library code they depend on at run time, run-time dependencies must be
5765 listed in @code{propagated-inputs} rather than @code{inputs}.
5767 @item @code{outputs} (default: @code{'("out")})
5768 The list of output names of the package. @xref{Packages with Multiple
5769 Outputs}, for typical uses of additional outputs.
5771 @item @code{native-search-paths} (default: @code{'()})
5772 @itemx @code{search-paths} (default: @code{'()})
5773 A list of @code{search-path-specification} objects describing
5774 search-path environment variables honored by the package.
5776 @item @code{replacement} (default: @code{#f})
5777 This must be either @code{#f} or a package object that will be used as a
5778 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5781 @item @code{synopsis}
5782 A one-line description of the package.
5784 @item @code{description}
5785 A more elaborate description of the package.
5787 @item @code{license}
5788 @cindex license, of packages
5789 The license of the package; a value from @code{(guix licenses)},
5790 or a list of such values.
5792 @item @code{home-page}
5793 The URL to the home-page of the package, as a string.
5795 @item @code{supported-systems} (default: @var{%supported-systems})
5796 The list of systems supported by the package, as strings of the form
5797 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5799 @item @code{location} (default: source location of the @code{package} form)
5800 The source location of the package. It is useful to override this when
5801 inheriting from another package, in which case this field is not
5802 automatically corrected.
5806 @deffn {Scheme Syntax} this-package
5807 When used in the @emph{lexical scope} of a package field definition, this
5808 identifier resolves to the package being defined.
5810 The example below shows how to add a package as a native input of itself when
5818 ;; When cross-compiled, Guile, for example, depends on
5819 ;; a native version of itself. Add it here.
5820 (native-inputs (if (%current-target-system)
5821 `(("self" ,this-package))
5825 It is an error to refer to @code{this-package} outside a package definition.
5828 @node origin Reference
5829 @subsection @code{origin} Reference
5831 This section summarizes all the options available in @code{origin}
5832 declarations (@pxref{Defining Packages}).
5834 @deftp {Data Type} origin
5835 This is the data type representing a source code origin.
5839 An object containing the URI of the source. The object type depends on
5840 the @code{method} (see below). For example, when using the
5841 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5842 values are: a URL represented as a string, or a list thereof.
5845 A procedure that handles the URI.
5850 @item @var{url-fetch} from @code{(guix download)}
5851 download a file from the HTTP, HTTPS, or FTP URL specified in the
5855 @item @var{git-fetch} from @code{(guix git-download)}
5856 clone the Git version control repository, and check out the revision
5857 specified in the @code{uri} field as a @code{git-reference} object; a
5858 @code{git-reference} looks like this:
5862 (url "https://git.savannah.gnu.org/git/hello.git")
5868 A bytevector containing the SHA-256 hash of the source. Typically the
5869 @code{base32} form is used here to generate the bytevector from a
5872 You can obtain this information using @code{guix download}
5873 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5876 @item @code{file-name} (default: @code{#f})
5877 The file name under which the source code should be saved. When this is
5878 @code{#f}, a sensible default value will be used in most cases. In case
5879 the source is fetched from a URL, the file name from the URL will be
5880 used. For version control checkouts, it is recommended to provide the
5881 file name explicitly because the default is not very descriptive.
5883 @item @code{patches} (default: @code{'()})
5884 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5885 file-like objects}) pointing to patches to be applied to the source.
5887 This list of patches must be unconditional. In particular, it cannot
5888 depend on the value of @code{%current-system} or
5889 @code{%current-target-system}.
5891 @item @code{snippet} (default: @code{#f})
5892 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5893 in the source directory. This is a convenient way to modify the source,
5894 sometimes more convenient than a patch.
5896 @item @code{patch-flags} (default: @code{'("-p1")})
5897 A list of command-line flags that should be passed to the @code{patch}
5900 @item @code{patch-inputs} (default: @code{#f})
5901 Input packages or derivations to the patching process. When this is
5902 @code{#f}, the usual set of inputs necessary for patching are provided,
5903 such as GNU@tie{}Patch.
5905 @item @code{modules} (default: @code{'()})
5906 A list of Guile modules that should be loaded during the patching
5907 process and while running the code in the @code{snippet} field.
5909 @item @code{patch-guile} (default: @code{#f})
5910 The Guile package that should be used in the patching process. When
5911 this is @code{#f}, a sensible default is used.
5917 @section Build Systems
5919 @cindex build system
5920 Each package definition specifies a @dfn{build system} and arguments for
5921 that build system (@pxref{Defining Packages}). This @code{build-system}
5922 field represents the build procedure of the package, as well as implicit
5923 dependencies of that build procedure.
5925 Build systems are @code{<build-system>} objects. The interface to
5926 create and manipulate them is provided by the @code{(guix build-system)}
5927 module, and actual build systems are exported by specific modules.
5929 @cindex bag (low-level package representation)
5930 Under the hood, build systems first compile package objects to
5931 @dfn{bags}. A @dfn{bag} is like a package, but with less
5932 ornamentation---in other words, a bag is a lower-level representation of
5933 a package, which includes all the inputs of that package, including some
5934 that were implicitly added by the build system. This intermediate
5935 representation is then compiled to a derivation (@pxref{Derivations}).
5937 Build systems accept an optional list of @dfn{arguments}. In package
5938 definitions, these are passed @i{via} the @code{arguments} field
5939 (@pxref{Defining Packages}). They are typically keyword arguments
5940 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5941 Guile Reference Manual}). The value of these arguments is usually
5942 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5943 by the daemon (@pxref{Derivations}).
5945 The main build system is @code{gnu-build-system}, which implements the
5946 standard build procedure for GNU and many other packages. It
5947 is provided by the @code{(guix build-system gnu)} module.
5949 @defvr {Scheme Variable} gnu-build-system
5950 @code{gnu-build-system} represents the GNU Build System, and variants
5951 thereof (@pxref{Configuration, configuration and makefile conventions,,
5952 standards, GNU Coding Standards}).
5954 @cindex build phases
5955 In a nutshell, packages using it are configured, built, and installed with
5956 the usual @code{./configure && make && make check && make install}
5957 command sequence. In practice, a few additional steps are often needed.
5958 All these steps are split up in separate @dfn{phases},
5959 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5960 modules for more details about the build phases.}:
5964 Unpack the source tarball, and change the current directory to the
5965 extracted source tree. If the source is actually a directory, copy it
5966 to the build tree, and enter that directory.
5968 @item patch-source-shebangs
5969 Patch shebangs encountered in source files so they refer to the right
5970 store file names. For instance, this changes @code{#!/bin/sh} to
5971 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
5974 Run the @file{configure} script with a number of default options, such
5975 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
5976 by the @code{#:configure-flags} argument.
5979 Run @code{make} with the list of flags specified with
5980 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
5981 (the default), build with @code{make -j}.
5984 Run @code{make check}, or some other target specified with
5985 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
5986 @code{#:parallel-tests?} argument is true (the default), run @code{make
5990 Run @code{make install} with the flags listed in @code{#:make-flags}.
5992 @item patch-shebangs
5993 Patch shebangs on the installed executable files.
5996 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
5997 is false), copying them to the @code{debug} output when available
5998 (@pxref{Installing Debugging Files}).
6001 @vindex %standard-phases
6002 The build-side module @code{(guix build gnu-build-system)} defines
6003 @code{%standard-phases} as the default list of build phases.
6004 @code{%standard-phases} is a list of symbol/procedure pairs, where the
6005 procedure implements the actual phase.
6007 The list of phases used for a particular package can be changed with the
6008 @code{#:phases} parameter. For instance, passing:
6011 #:phases (modify-phases %standard-phases (delete 'configure))
6014 means that all the phases described above will be used, except the
6015 @code{configure} phase.
6017 In addition, this build system ensures that the ``standard'' environment
6018 for GNU packages is available. This includes tools such as GCC, libc,
6019 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
6020 build-system gnu)} module for a complete list). We call these the
6021 @dfn{implicit inputs} of a package, because package definitions do not
6022 have to mention them.
6025 Other @code{<build-system>} objects are defined to support other
6026 conventions and tools used by free software packages. They inherit most
6027 of @code{gnu-build-system}, and differ mainly in the set of inputs
6028 implicitly added to the build process, and in the list of phases
6029 executed. Some of these build systems are listed below.
6031 @defvr {Scheme Variable} ant-build-system
6032 This variable is exported by @code{(guix build-system ant)}. It
6033 implements the build procedure for Java packages that can be built with
6034 @url{https://ant.apache.org/, Ant build tool}.
6036 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
6037 provided by the @code{icedtea} package to the set of inputs. Different
6038 packages can be specified with the @code{#:ant} and @code{#:jdk}
6039 parameters, respectively.
6041 When the original package does not provide a suitable Ant build file,
6042 the parameter @code{#:jar-name} can be used to generate a minimal Ant
6043 build file @file{build.xml} with tasks to build the specified jar
6044 archive. In this case the parameter @code{#:source-dir} can be used to
6045 specify the source sub-directory, defaulting to ``src''.
6047 The @code{#:main-class} parameter can be used with the minimal ant
6048 buildfile to specify the main class of the resulting jar. This makes the
6049 jar file executable. The @code{#:test-include} parameter can be used to
6050 specify the list of junit tests to run. It defaults to
6051 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
6052 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
6053 because abstract classes cannot be run as tests.
6055 The parameter @code{#:build-target} can be used to specify the Ant task
6056 that should be run during the @code{build} phase. By default the
6057 ``jar'' task will be run.
6061 @defvr {Scheme Variable} android-ndk-build-system
6062 @cindex Android distribution
6063 @cindex Android NDK build system
6064 This variable is exported by @code{(guix build-system android-ndk)}. It
6065 implements a build procedure for Android NDK (native development kit)
6066 packages using a Guix-specific build process.
6068 The build system assumes that packages install their public interface
6069 (header) files to the subdirectory "include" of the "out" output and
6070 their libraries to the subdirectory "lib" of the "out" output.
6072 It's also assumed that the union of all the dependencies of a package
6073 has no conflicting files.
6075 For the time being, cross-compilation is not supported - so right now
6076 the libraries and header files are assumed to be host tools.
6080 @defvr {Scheme Variable} asdf-build-system/source
6081 @defvrx {Scheme Variable} asdf-build-system/sbcl
6082 @defvrx {Scheme Variable} asdf-build-system/ecl
6084 These variables, exported by @code{(guix build-system asdf)}, implement
6085 build procedures for Common Lisp packages using
6086 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
6087 definition facility for Common Lisp programs and libraries.
6089 The @code{asdf-build-system/source} system installs the packages in
6090 source form, and can be loaded using any common lisp implementation, via
6091 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
6092 systems in the format which a particular implementation understands.
6093 These build systems can also be used to produce executable programs, or
6094 lisp images which contain a set of packages pre-loaded.
6096 The build system uses naming conventions. For binary packages, the
6097 package name should be prefixed with the lisp implementation, such as
6098 @code{sbcl-} for @code{asdf-build-system/sbcl}.
6100 Additionally, the corresponding source package should be labeled using
6101 the same convention as python packages (see @ref{Python Modules}), using
6102 the @code{cl-} prefix.
6104 For binary packages, each system should be defined as a Guix package.
6105 If one package @code{origin} contains several systems, package variants
6106 can be created in order to build all the systems. Source packages,
6107 which use @code{asdf-build-system/source}, may contain several systems.
6109 In order to create executable programs and images, the build-side
6110 procedures @code{build-program} and @code{build-image} can be used.
6111 They should be called in a build phase after the @code{create-symlinks}
6112 phase, so that the system which was just built can be used within the
6113 resulting image. @code{build-program} requires a list of Common Lisp
6114 expressions to be passed as the @code{#:entry-program} argument.
6116 If the system is not defined within its own @code{.asd} file of the same
6117 name, then the @code{#:asd-file} parameter should be used to specify
6118 which file the system is defined in. Furthermore, if the package
6119 defines a system for its tests in a separate file, it will be loaded
6120 before the tests are run if it is specified by the
6121 @code{#:test-asd-file} parameter. If it is not set, the files
6122 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
6123 and @code{test.asd} will be tried if they exist.
6125 If for some reason the package must be named in a different way than the
6126 naming conventions suggest, the @code{#:asd-system-name} parameter can
6127 be used to specify the name of the system.
6131 @defvr {Scheme Variable} cargo-build-system
6132 @cindex Rust programming language
6133 @cindex Cargo (Rust build system)
6134 This variable is exported by @code{(guix build-system cargo)}. It
6135 supports builds of packages using Cargo, the build tool of the
6136 @uref{https://www.rust-lang.org, Rust programming language}.
6138 It adds @code{rustc} and @code{cargo} to the set of inputs.
6139 A different Rust package can be specified with the @code{#:rust} parameter.
6141 Regular cargo dependencies should be added to the package definition via the
6142 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
6143 spec can be a package or a source definition. Note that the spec must
6144 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
6145 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
6146 should be added to the package definition via the
6147 @code{#:cargo-development-inputs} parameter.
6149 In its @code{configure} phase, this build system will make any source inputs
6150 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6151 parameters available to cargo. It will also remove an included
6152 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6153 @code{build} phase. The @code{install} phase installs any crate the binaries
6154 if they are defined by the crate.
6158 @defvr {Scheme Variable} copy-build-system
6159 @cindex (copy build system)
6160 This variable is exported by @code{(guix build-system copy)}. It
6161 supports builds of simple packages that don't require much compiling,
6162 mostly just moving files around.
6164 It adds much of the @code{gnu-build-system} packages to the set of
6165 inputs. Because of this, the @code{copy-build-system} does not require
6166 all the boilerplate code often needed for the
6167 @code{trivial-build-system}.
6169 To further simplify the file installation process, an
6170 @code{#:install-plan} argument is exposed to let the packager specify
6171 which files go where. The install plan is a list of @code{(@var{source}
6172 @var{target} [@var{filters}])}. @var{filters} are optional.
6175 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
6177 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
6178 @item Otherwise install @var{source} as @var{target}.
6181 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
6182 the trailing slash of @var{target} is implied with the same meaning
6185 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
6186 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
6187 @code{#:exclude-regexp}, only select files are installed depending on
6188 the filters. Each filters is specified by a list of strings.
6190 @item With @code{#:include}, install all the files which the path suffix matches
6191 at least one of the elements in the given list.
6192 @item With @code{#:include-regexp}, install all the files which the
6193 subpaths match at least one of the regular expressions in the given
6195 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
6196 are the complement of their inclusion counterpart. Without @code{#:include} flags,
6197 install all files but those matching the exclusion filters.
6198 If both inclusions and exclusions are specified, the exclusions are done
6199 on top of the inclusions.
6202 In all cases, the paths relative to @var{source} are preserved within
6209 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
6210 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
6211 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
6212 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
6213 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
6214 @file{share/my-app/sub/file}.
6215 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
6216 @file{share/my-app/file}.
6221 @cindex Clojure (programming language)
6222 @cindex simple Clojure build system
6223 @defvr {Scheme Variable} clojure-build-system
6224 This variable is exported by @code{(guix build-system clojure)}. It implements
6225 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6226 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6229 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6230 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6231 @code{#:zip} parameters, respectively.
6233 A list of source directories, test directories and jar names can be specified
6234 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6235 parameters, respectively. Compile directory and main class can be specified
6236 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6237 Other parameters are documented below.
6239 This build system is an extension of @code{ant-build-system}, but with the
6240 following phases changed:
6245 This phase calls @code{compile} in Clojure to compile source files and runs
6246 @command{jar} to create jars from both source files and compiled files
6247 according to the include list and exclude list specified in
6248 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6249 has priority over the include list. These lists consist of symbols
6250 representing Clojure libraries or the special keyword @code{#:all} representing
6251 all Clojure libraries found under the source directories. The parameter
6252 @code{#:omit-source?} decides if source should be included into the jars.
6255 This phase runs tests according to the include list and exclude list specified
6256 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6257 meanings are analogous to that of @code{#:aot-include} and
6258 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6259 stands for all Clojure libraries found under the test directories. The
6260 parameter @code{#:tests?} decides if tests should be run.
6263 This phase installs all jars built previously.
6266 Apart from the above, this build system also contains an additional phase:
6271 This phase installs all top-level files with base name matching
6272 @code{%doc-regex}. A different regex can be specified with the
6273 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6274 directories specified in @code{#:doc-dirs} are installed as well.
6278 @defvr {Scheme Variable} cmake-build-system
6279 This variable is exported by @code{(guix build-system cmake)}. It
6280 implements the build procedure for packages using the
6281 @url{https://www.cmake.org, CMake build tool}.
6283 It automatically adds the @code{cmake} package to the set of inputs.
6284 Which package is used can be specified with the @code{#:cmake}
6287 The @code{#:configure-flags} parameter is taken as a list of flags
6288 passed to the @command{cmake} command. The @code{#:build-type}
6289 parameter specifies in abstract terms the flags passed to the compiler;
6290 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6291 debugging information''), which roughly means that code is compiled with
6292 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6295 @defvr {Scheme Variable} dune-build-system
6296 This variable is exported by @code{(guix build-system dune)}. It
6297 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6298 tool for the OCaml programming language. It is implemented as an extension
6299 of the @code{ocaml-build-system} which is described below. As such, the
6300 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6303 It automatically adds the @code{dune} package to the set of inputs.
6304 Which package is used can be specified with the @code{#:dune}
6307 There is no @code{configure} phase because dune packages typically don't
6308 need to be configured. The @code{#:build-flags} parameter is taken as a
6309 list of flags passed to the @code{dune} command during the build.
6311 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6312 command instead of the more recent @code{dune} command while building
6313 a package. Its default value is @code{#f}.
6315 The @code{#:package} parameter can be passed to specify a package name, which
6316 is useful when a package contains multiple packages and you want to build
6317 only one of them. This is equivalent to passing the @code{-p} argument to
6321 @defvr {Scheme Variable} go-build-system
6322 This variable is exported by @code{(guix build-system go)}. It
6323 implements a build procedure for Go packages using the standard
6324 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6325 Go build mechanisms}.
6327 The user is expected to provide a value for the key @code{#:import-path}
6328 and, in some cases, @code{#:unpack-path}. The
6329 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6330 corresponds to the file system path expected by the package's build
6331 scripts and any referring packages, and provides a unique way to
6332 refer to a Go package. It is typically based on a combination of the
6333 package source code's remote URI and file system hierarchy structure. In
6334 some cases, you will need to unpack the package's source code to a
6335 different directory structure than the one indicated by the import path,
6336 and @code{#:unpack-path} should be used in such cases.
6338 Packages that provide Go libraries should install their source code into
6339 the built output. The key @code{#:install-source?}, which defaults to
6340 @code{#t}, controls whether or not the source code is installed. It can
6341 be set to @code{#f} for packages that only provide executable files.
6344 @defvr {Scheme Variable} glib-or-gtk-build-system
6345 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6346 is intended for use with packages making use of GLib or GTK+.
6348 This build system adds the following two phases to the ones defined by
6349 @code{gnu-build-system}:
6352 @item glib-or-gtk-wrap
6353 The phase @code{glib-or-gtk-wrap} ensures that programs in
6354 @file{bin/} are able to find GLib ``schemas'' and
6355 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6356 modules}. This is achieved by wrapping the programs in launch scripts
6357 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
6358 environment variables.
6360 It is possible to exclude specific package outputs from that wrapping
6361 process by listing their names in the
6362 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6363 when an output is known not to contain any GLib or GTK+ binaries, and
6364 where wrapping would gratuitously add a dependency of that output on
6367 @item glib-or-gtk-compile-schemas
6368 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6369 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6370 GSettings schemas} of GLib are compiled. Compilation is performed by the
6371 @command{glib-compile-schemas} program. It is provided by the package
6372 @code{glib:bin} which is automatically imported by the build system.
6373 The @code{glib} package providing @command{glib-compile-schemas} can be
6374 specified with the @code{#:glib} parameter.
6377 Both phases are executed after the @code{install} phase.
6380 @defvr {Scheme Variable} guile-build-system
6381 This build system is for Guile packages that consist exclusively of Scheme
6382 code and that are so lean that they don't even have a makefile, let alone a
6383 @file{configure} script. It compiles Scheme code using @command{guild
6384 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6385 installs the @file{.scm} and @file{.go} files in the right place. It also
6386 installs documentation.
6388 This build system supports cross-compilation by using the @code{--target}
6389 option of @command{guild compile}.
6391 Packages built with @code{guile-build-system} must provide a Guile package in
6392 their @code{native-inputs} field.
6395 @defvr {Scheme Variable} julia-build-system
6396 This variable is exported by @code{(guix build-system julia)}. It implements
6397 the build procedure used by @uref{https://julialang.org/, julia} packages,
6398 which essentially is similar to running @command{julia -e 'using Pkg;
6399 Pkg.add(package)'} in an environment where @code{JULIA_LOAD_PATH} contains the
6400 paths to all Julia package inputs. Tests are run not run.
6402 Julia packages require the source @code{file-name} to be the real name of the
6403 package, correctly capitalized.
6405 For packages requiring shared library dependencies, you may need to write the
6406 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6407 variable = /gnu/store/library.so} for each dependency, plus a void function
6408 @code{check_deps() = nothing}.
6410 Some older packages that aren't using @file{Package.toml} yet, will require
6411 this file to be created, too. The function @code{julia-create-package-toml}
6412 helps creating the file. You need to pass the outputs and the source of the
6413 package, it's name (the same as the @code{file-name} parameter), the package
6414 uuid, the package version, and a list of dependencies specified by their name
6418 @defvr {Scheme Variable} minify-build-system
6419 This variable is exported by @code{(guix build-system minify)}. It
6420 implements a minification procedure for simple JavaScript packages.
6422 It adds @code{uglify-js} to the set of inputs and uses it to compress
6423 all JavaScript files in the @file{src} directory. A different minifier
6424 package can be specified with the @code{#:uglify-js} parameter, but it
6425 is expected that the package writes the minified code to the standard
6428 When the input JavaScript files are not all located in the @file{src}
6429 directory, the parameter @code{#:javascript-files} can be used to
6430 specify a list of file names to feed to the minifier.
6433 @defvr {Scheme Variable} ocaml-build-system
6434 This variable is exported by @code{(guix build-system ocaml)}. It implements
6435 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6436 of choosing the correct set of commands to run for each package. OCaml
6437 packages can expect many different commands to be run. This build system will
6440 When the package has a @file{setup.ml} file present at the top-level, it will
6441 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6442 @code{ocaml setup.ml -install}. The build system will assume that this file
6443 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6444 care of setting the prefix and enabling tests if they are not disabled. You
6445 can pass configure and build flags with the @code{#:configure-flags} and
6446 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6447 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6448 bypass this system in the build and install phases.
6450 When the package has a @file{configure} file, it is assumed that it is a
6451 hand-made configure script that requires a different argument format than
6452 in the @code{gnu-build-system}. You can add more flags with the
6453 @code{#:configure-flags} key.
6455 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6456 @code{#t}), it will be used and more flags can be passed to the build and
6457 install phases with the @code{#:make-flags} key.
6459 Finally, some packages do not have these files and use a somewhat standard
6460 location for its build system. In that case, the build system will run
6461 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6462 providing the path to the required findlib module. Additional flags can
6463 be passed via the @code{#:build-flags} key. Install is taken care of by
6464 @command{opam-installer}. In this case, the @code{opam} package must
6465 be added to the @code{native-inputs} field of the package definition.
6467 Note that most OCaml packages assume they will be installed in the same
6468 directory as OCaml, which is not what we want in guix. In particular, they
6469 will install @file{.so} files in their module's directory, which is usually
6470 fine because it is in the OCaml compiler directory. In guix though, these
6471 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6472 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6473 @file{.so} libraries should be installed.
6476 @defvr {Scheme Variable} python-build-system
6477 This variable is exported by @code{(guix build-system python)}. It
6478 implements the more or less standard build procedure used by Python
6479 packages, which consists in running @code{python setup.py build} and
6480 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6482 For packages that install stand-alone Python programs under @code{bin/},
6483 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6484 environment variable points to all the Python libraries they depend on.
6486 Which Python package is used to perform the build can be specified with
6487 the @code{#:python} parameter. This is a useful way to force a package
6488 to be built for a specific version of the Python interpreter, which
6489 might be necessary if the package is only compatible with a single
6490 interpreter version.
6492 By default guix calls @code{setup.py} under control of
6493 @code{setuptools}, much like @command{pip} does. Some packages are not
6494 compatible with setuptools (and pip), thus you can disable this by
6495 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6498 @defvr {Scheme Variable} perl-build-system
6499 This variable is exported by @code{(guix build-system perl)}. It
6500 implements the standard build procedure for Perl packages, which either
6501 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6502 followed by @code{Build} and @code{Build install}; or in running
6503 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6504 @code{make} and @code{make install}, depending on which of
6505 @code{Build.PL} or @code{Makefile.PL} is present in the package
6506 distribution. Preference is given to the former if both @code{Build.PL}
6507 and @code{Makefile.PL} exist in the package distribution. This
6508 preference can be reversed by specifying @code{#t} for the
6509 @code{#:make-maker?} parameter.
6511 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6512 passes flags specified by the @code{#:make-maker-flags} or
6513 @code{#:module-build-flags} parameter, respectively.
6515 Which Perl package is used can be specified with @code{#:perl}.
6518 @defvr {Scheme Variable} qt-build-system
6519 This variable is exported by @code{(guix build-system qt)}. It
6520 is intended for use with applications using Qt or KDE.
6522 This build system adds the following two phases to the ones defined by
6523 @code{cmake-build-system}:
6527 The phase @code{check-setup} prepares the environment for running
6528 the checks as commonly used by Qt test programs.
6529 For now this only sets some environment variables:
6530 @code{QT_QPA_PLATFORM=offscreen},
6531 @code{DBUS_FATAL_WARNINGS=0} and
6532 @code{CTEST_OUTPUT_ON_FAILURE=1}.
6534 This phase is added before the @code{check} phase.
6535 It's a separate phase to ease adjusting if necessary.
6538 The phase @code{qt-wrap}
6539 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
6540 and output. In case some path is found, all programs in the output's
6541 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
6542 are wrapped in scripts defining the necessary environment variables.
6544 It is possible to exclude specific package outputs from that wrapping process
6545 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
6546 This is useful when an output is known not to contain any Qt binaries, and
6547 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
6550 This phase is added after the @code{install} phase.
6554 @defvr {Scheme Variable} r-build-system
6555 This variable is exported by @code{(guix build-system r)}. It
6556 implements the build procedure used by @uref{https://r-project.org, R}
6557 packages, which essentially is little more than running @code{R CMD
6558 INSTALL --library=/gnu/store/@dots{}} in an environment where
6559 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6560 are run after installation using the R function
6561 @code{tools::testInstalledPackage}.
6564 @defvr {Scheme Variable} rakudo-build-system
6565 This variable is exported by @code{(guix build-system rakudo)}. It
6566 implements the build procedure used by @uref{https://rakudo.org/,
6567 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6568 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6569 installs the binaries, library files and the resources, as well as wrap
6570 the files under the @code{bin/} directory. Tests can be skipped by
6571 passing @code{#f} to the @code{tests?} parameter.
6573 Which rakudo package is used can be specified with @code{rakudo}.
6574 Which perl6-tap-harness package used for the tests can be specified with
6575 @code{#:prove6} or removed by passing @code{#f} to the
6576 @code{with-prove6?} parameter.
6577 Which perl6-zef package used for tests and installing can be specified
6578 with @code{#:zef} or removed by passing @code{#f} to the
6579 @code{with-zef?} parameter.
6582 @defvr {Scheme Variable} texlive-build-system
6583 This variable is exported by @code{(guix build-system texlive)}. It is
6584 used to build TeX packages in batch mode with a specified engine. The
6585 build system sets the @code{TEXINPUTS} variable to find all TeX source
6586 files in the inputs.
6588 By default it runs @code{luatex} on all files ending on @code{ins}. A
6589 different engine and format can be specified with the
6590 @code{#:tex-format} argument. Different build targets can be specified
6591 with the @code{#:build-targets} argument, which expects a list of file
6592 names. The build system adds only @code{texlive-bin} and
6593 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6594 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6595 and @code{#:texlive-latex-base}, respectively.
6597 The @code{#:tex-directory} parameter tells the build system where to
6598 install the built files under the texmf tree.
6601 @defvr {Scheme Variable} ruby-build-system
6602 This variable is exported by @code{(guix build-system ruby)}. It
6603 implements the RubyGems build procedure used by Ruby packages, which
6604 involves running @code{gem build} followed by @code{gem install}.
6606 The @code{source} field of a package that uses this build system
6607 typically references a gem archive, since this is the format that Ruby
6608 developers use when releasing their software. The build system unpacks
6609 the gem archive, potentially patches the source, runs the test suite,
6610 repackages the gem, and installs it. Additionally, directories and
6611 tarballs may be referenced to allow building unreleased gems from Git or
6612 a traditional source release tarball.
6614 Which Ruby package is used can be specified with the @code{#:ruby}
6615 parameter. A list of additional flags to be passed to the @command{gem}
6616 command can be specified with the @code{#:gem-flags} parameter.
6619 @defvr {Scheme Variable} waf-build-system
6620 This variable is exported by @code{(guix build-system waf)}. It
6621 implements a build procedure around the @code{waf} script. The common
6622 phases---@code{configure}, @code{build}, and @code{install}---are
6623 implemented by passing their names as arguments to the @code{waf}
6626 The @code{waf} script is executed by the Python interpreter. Which
6627 Python package is used to run the script can be specified with the
6628 @code{#:python} parameter.
6631 @defvr {Scheme Variable} scons-build-system
6632 This variable is exported by @code{(guix build-system scons)}. It
6633 implements the build procedure used by the SCons software construction
6634 tool. This build system runs @code{scons} to build the package,
6635 @code{scons test} to run tests, and then @code{scons install} to install
6638 Additional flags to be passed to @code{scons} can be specified with the
6639 @code{#:scons-flags} parameter. The default build and install targets
6640 can be overridden with @code{#:build-targets} and
6641 @code{#:install-targets} respectively. The version of Python used to
6642 run SCons can be specified by selecting the appropriate SCons package
6643 with the @code{#:scons} parameter.
6646 @defvr {Scheme Variable} haskell-build-system
6647 This variable is exported by @code{(guix build-system haskell)}. It
6648 implements the Cabal build procedure used by Haskell packages, which
6649 involves running @code{runhaskell Setup.hs configure
6650 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6651 Instead of installing the package by running @code{runhaskell Setup.hs
6652 install}, to avoid trying to register libraries in the read-only
6653 compiler store directory, the build system uses @code{runhaskell
6654 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6655 addition, the build system generates the package documentation by
6656 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6657 is passed. Optional Haddock parameters can be passed with the help of
6658 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6659 not found, the build system looks for @code{Setup.lhs} instead.
6661 Which Haskell compiler is used can be specified with the @code{#:haskell}
6662 parameter which defaults to @code{ghc}.
6665 @defvr {Scheme Variable} dub-build-system
6666 This variable is exported by @code{(guix build-system dub)}. It
6667 implements the Dub build procedure used by D packages, which
6668 involves running @code{dub build} and @code{dub run}.
6669 Installation is done by copying the files manually.
6671 Which D compiler is used can be specified with the @code{#:ldc}
6672 parameter which defaults to @code{ldc}.
6675 @defvr {Scheme Variable} emacs-build-system
6676 This variable is exported by @code{(guix build-system emacs)}. It
6677 implements an installation procedure similar to the packaging system
6678 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6680 It first creates the @code{@code{package}-autoloads.el} file, then it
6681 byte compiles all Emacs Lisp files. Differently from the Emacs
6682 packaging system, the Info documentation files are moved to the standard
6683 documentation directory and the @file{dir} file is deleted. Each
6684 package is installed in its own directory under
6685 @file{share/emacs/site-lisp/guix.d}.
6688 @defvr {Scheme Variable} font-build-system
6689 This variable is exported by @code{(guix build-system font)}. It
6690 implements an installation procedure for font packages where upstream
6691 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6692 need to be copied into place. It copies font files to standard
6693 locations in the output directory.
6696 @defvr {Scheme Variable} meson-build-system
6697 This variable is exported by @code{(guix build-system meson)}. It
6698 implements the build procedure for packages that use
6699 @url{https://mesonbuild.com, Meson} as their build system.
6701 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6702 of inputs, and they can be changed with the parameters @code{#:meson}
6703 and @code{#:ninja} if needed. The default Meson is
6704 @code{meson-for-build}, which is special because it doesn't clear the
6705 @code{RUNPATH} of binaries and libraries when they are installed.
6707 This build system is an extension of @code{gnu-build-system}, but with the
6708 following phases changed to some specific for Meson:
6713 The phase runs @code{meson} with the flags specified in
6714 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6715 @code{plain} unless something else is specified in @code{#:build-type}.
6718 The phase runs @code{ninja} to build the package in parallel by default, but
6719 this can be changed with @code{#:parallel-build?}.
6722 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6723 which is @code{"test"} by default.
6726 The phase runs @code{ninja install} and can not be changed.
6729 Apart from that, the build system also adds the following phases:
6734 This phase ensures that all binaries can find the libraries they need.
6735 It searches for required libraries in subdirectories of the package being
6736 built, and adds those to @code{RUNPATH} where needed. It also removes
6737 references to libraries left over from the build phase by
6738 @code{meson-for-build}, such as test dependencies, that aren't actually
6739 required for the program to run.
6741 @item glib-or-gtk-wrap
6742 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6743 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6745 @item glib-or-gtk-compile-schemas
6746 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6747 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6751 @defvr {Scheme Variable} linux-module-build-system
6752 @code{linux-module-build-system} allows building Linux kernel modules.
6754 @cindex build phases
6755 This build system is an extension of @code{gnu-build-system}, but with the
6756 following phases changed:
6761 This phase configures the environment so that the Linux kernel's Makefile
6762 can be used to build the external kernel module.
6765 This phase uses the Linux kernel's Makefile in order to build the external
6769 This phase uses the Linux kernel's Makefile in order to install the external
6773 It is possible and useful to specify the Linux kernel to use for building
6774 the module (in the "arguments" form of a package using the
6775 linux-module-build-system, use the key #:linux to specify it).
6778 @defvr {Scheme Variable} node-build-system
6779 This variable is exported by @code{(guix build-system node)}. It
6780 implements the build procedure used by @uref{http://nodejs.org,
6781 Node.js}, which implements an approximation of the @code{npm install}
6782 command, followed by an @code{npm test} command.
6784 Which Node.js package is used to interpret the @code{npm} commands can
6785 be specified with the @code{#:node} parameter which defaults to
6789 Lastly, for packages that do not need anything as sophisticated, a
6790 ``trivial'' build system is provided. It is trivial in the sense that
6791 it provides basically no support: it does not pull any implicit inputs,
6792 and does not have a notion of build phases.
6794 @defvr {Scheme Variable} trivial-build-system
6795 This variable is exported by @code{(guix build-system trivial)}.
6797 This build system requires a @code{#:builder} argument. This argument
6798 must be a Scheme expression that builds the package output(s)---as
6799 with @code{build-expression->derivation} (@pxref{Derivations,
6800 @code{build-expression->derivation}}).
6810 Conceptually, the @dfn{store} is the place where derivations that have
6811 been built successfully are stored---by default, @file{/gnu/store}.
6812 Sub-directories in the store are referred to as @dfn{store items} or
6813 sometimes @dfn{store paths}. The store has an associated database that
6814 contains information such as the store paths referred to by each store
6815 path, and the list of @emph{valid} store items---results of successful
6816 builds. This database resides in @file{@var{localstatedir}/guix/db},
6817 where @var{localstatedir} is the state directory specified @i{via}
6818 @option{--localstatedir} at configure time, usually @file{/var}.
6820 The store is @emph{always} accessed by the daemon on behalf of its clients
6821 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6822 connect to the daemon over a Unix-domain socket, send requests to it,
6823 and read the result---these are remote procedure calls, or RPCs.
6826 Users must @emph{never} modify files under @file{/gnu/store} directly.
6827 This would lead to inconsistencies and break the immutability
6828 assumptions of Guix's functional model (@pxref{Introduction}).
6830 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6831 how to check the integrity of the store and attempt recovery from
6832 accidental modifications.
6835 The @code{(guix store)} module provides procedures to connect to the
6836 daemon, and to perform RPCs. These are described below. By default,
6837 @code{open-connection}, and thus all the @command{guix} commands,
6838 connect to the local daemon or to the URI specified by the
6839 @code{GUIX_DAEMON_SOCKET} environment variable.
6841 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6842 When set, the value of this variable should be a file name or a URI
6843 designating the daemon endpoint. When it is a file name, it denotes a
6844 Unix-domain socket to connect to. In addition to file names, the
6845 supported URI schemes are:
6850 These are for Unix-domain sockets.
6851 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6852 @file{/var/guix/daemon-socket/socket}.
6855 @cindex daemon, remote access
6856 @cindex remote access to the daemon
6857 @cindex daemon, cluster setup
6858 @cindex clusters, daemon setup
6859 These URIs denote connections over TCP/IP, without encryption nor
6860 authentication of the remote host. The URI must specify the host name
6861 and optionally a port number (by default port 44146 is used):
6864 guix://master.guix.example.org:1234
6867 This setup is suitable on local networks, such as clusters, where only
6868 trusted nodes may connect to the build daemon at
6869 @code{master.guix.example.org}.
6871 The @code{--listen} option of @command{guix-daemon} can be used to
6872 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6876 @cindex SSH access to build daemons
6877 These URIs allow you to connect to a remote daemon over SSH. This
6878 feature requires Guile-SSH (@pxref{Requirements}) and a working
6879 @code{guile} binary in @code{PATH} on the destination machine. It
6880 supports public key and GSSAPI authentication. A typical URL might look
6884 ssh://charlie@@guix.example.org:22
6887 As for @command{guix copy}, the usual OpenSSH client configuration files
6888 are honored (@pxref{Invoking guix copy}).
6891 Additional URI schemes may be supported in the future.
6893 @c XXX: Remove this note when the protocol incurs fewer round trips
6894 @c and when (guix derivations) no longer relies on file system access.
6896 The ability to connect to remote build daemons is considered
6897 experimental as of @value{VERSION}. Please get in touch with us to
6898 share any problems or suggestions you may have (@pxref{Contributing}).
6902 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6903 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6904 @var{reserve-space?} is true, instruct it to reserve a little bit of
6905 extra space on the file system so that the garbage collector can still
6906 operate should the disk become full. Return a server object.
6908 @var{file} defaults to @code{%default-socket-path}, which is the normal
6909 location given the options that were passed to @command{configure}.
6912 @deffn {Scheme Procedure} close-connection @var{server}
6913 Close the connection to @var{server}.
6916 @defvr {Scheme Variable} current-build-output-port
6917 This variable is bound to a SRFI-39 parameter, which refers to the port
6918 where build and error logs sent by the daemon should be written.
6921 Procedures that make RPCs all take a server object as their first
6924 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6925 @cindex invalid store items
6926 Return @code{#t} when @var{path} designates a valid store item and
6927 @code{#f} otherwise (an invalid item may exist on disk but still be
6928 invalid, for instance because it is the result of an aborted or failed
6931 A @code{&store-protocol-error} condition is raised if @var{path} is not
6932 prefixed by the store directory (@file{/gnu/store}).
6935 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6936 Add @var{text} under file @var{name} in the store, and return its store
6937 path. @var{references} is the list of store paths referred to by the
6938 resulting store path.
6941 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6943 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6944 file names, or derivation/output pairs, using the specified
6945 @var{mode}---@code{(build-mode normal)} by default.
6948 Note that the @code{(guix monads)} module provides a monad as well as
6949 monadic versions of the above procedures, with the goal of making it
6950 more convenient to work with code that accesses the store (@pxref{The
6954 @i{This section is currently incomplete.}
6957 @section Derivations
6960 Low-level build actions and the environment in which they are performed
6961 are represented by @dfn{derivations}. A derivation contains the
6962 following pieces of information:
6966 The outputs of the derivation---derivations produce at least one file or
6967 directory in the store, but may produce more.
6970 @cindex build-time dependencies
6971 @cindex dependencies, build-time
6972 The inputs of the derivations---i.e., its build-time dependencies---which may
6973 be other derivations or plain files in the store (patches, build scripts,
6977 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
6980 The file name of a build script in the store, along with the arguments
6984 A list of environment variables to be defined.
6988 @cindex derivation path
6989 Derivations allow clients of the daemon to communicate build actions to
6990 the store. They exist in two forms: as an in-memory representation,
6991 both on the client- and daemon-side, and as files in the store whose
6992 name end in @code{.drv}---these files are referred to as @dfn{derivation
6993 paths}. Derivations paths can be passed to the @code{build-derivations}
6994 procedure to perform the build actions they prescribe (@pxref{The
6997 @cindex fixed-output derivations
6998 Operations such as file downloads and version-control checkouts for
6999 which the expected content hash is known in advance are modeled as
7000 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
7001 of a fixed-output derivation are independent of its inputs---e.g., a
7002 source code download produces the same result regardless of the download
7003 method and tools being used.
7006 @cindex run-time dependencies
7007 @cindex dependencies, run-time
7008 The outputs of derivations---i.e., the build results---have a set of
7009 @dfn{references}, as reported by the @code{references} RPC or the
7010 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
7011 are the set of run-time dependencies of the build results. References are a
7012 subset of the inputs of the derivation; this subset is automatically computed
7013 by the build daemon by scanning all the files in the outputs.
7015 The @code{(guix derivations)} module provides a representation of
7016 derivations as Scheme objects, along with procedures to create and
7017 otherwise manipulate derivations. The lowest-level primitive to create
7018 a derivation is the @code{derivation} procedure:
7020 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
7021 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7022 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
7023 [#:system (%current-system)] [#:references-graphs #f] @
7024 [#:allowed-references #f] [#:disallowed-references #f] @
7025 [#:leaked-env-vars #f] [#:local-build? #f] @
7026 [#:substitutable? #t] [#:properties '()]
7027 Build a derivation with the given arguments, and return the resulting
7028 @code{<derivation>} object.
7030 When @var{hash} and @var{hash-algo} are given, a
7031 @dfn{fixed-output derivation} is created---i.e., one whose result is
7032 known in advance, such as a file download. If, in addition,
7033 @var{recursive?} is true, then that fixed output may be an executable
7034 file or a directory and @var{hash} must be the hash of an archive
7035 containing this output.
7037 When @var{references-graphs} is true, it must be a list of file
7038 name/store path pairs. In that case, the reference graph of each store
7039 path is exported in the build environment in the corresponding file, in
7040 a simple text format.
7042 When @var{allowed-references} is true, it must be a list of store items
7043 or outputs that the derivation's output may refer to. Likewise,
7044 @var{disallowed-references}, if true, must be a list of things the
7045 outputs may @emph{not} refer to.
7047 When @var{leaked-env-vars} is true, it must be a list of strings
7048 denoting environment variables that are allowed to ``leak'' from the
7049 daemon's environment to the build environment. This is only applicable
7050 to fixed-output derivations---i.e., when @var{hash} is true. The main
7051 use is to allow variables such as @code{http_proxy} to be passed to
7052 derivations that download files.
7054 When @var{local-build?} is true, declare that the derivation is not a
7055 good candidate for offloading and should rather be built locally
7056 (@pxref{Daemon Offload Setup}). This is the case for small derivations
7057 where the costs of data transfers would outweigh the benefits.
7059 When @var{substitutable?} is false, declare that substitutes of the
7060 derivation's output should not be used (@pxref{Substitutes}). This is
7061 useful, for instance, when building packages that capture details of the
7062 host CPU instruction set.
7064 @var{properties} must be an association list describing ``properties'' of the
7065 derivation. It is kept as-is, uninterpreted, in the derivation.
7069 Here's an example with a shell script as its builder, assuming
7070 @var{store} is an open connection to the daemon, and @var{bash} points
7071 to a Bash executable in the store:
7074 (use-modules (guix utils)
7078 (let ((builder ; add the Bash script to the store
7079 (add-text-to-store store "my-builder.sh"
7080 "echo hello world > $out\n" '())))
7081 (derivation store "foo"
7082 bash `("-e" ,builder)
7083 #:inputs `((,bash) (,builder))
7084 #:env-vars '(("HOME" . "/homeless"))))
7085 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
7088 As can be guessed, this primitive is cumbersome to use directly. A
7089 better approach is to write build scripts in Scheme, of course! The
7090 best course of action for that is to write the build code as a
7091 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
7092 information, @pxref{G-Expressions}.
7094 Once upon a time, @code{gexp->derivation} did not exist and constructing
7095 derivations with build code written in Scheme was achieved with
7096 @code{build-expression->derivation}, documented below. This procedure
7097 is now deprecated in favor of the much nicer @code{gexp->derivation}.
7099 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
7100 @var{name} @var{exp} @
7101 [#:system (%current-system)] [#:inputs '()] @
7102 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7103 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7104 [#:references-graphs #f] [#:allowed-references #f] @
7105 [#:disallowed-references #f] @
7106 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
7107 Return a derivation that executes Scheme expression @var{exp} as a
7108 builder for derivation @var{name}. @var{inputs} must be a list of
7109 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
7110 @code{"out"} is assumed. @var{modules} is a list of names of Guile
7111 modules from the current search path to be copied in the store,
7112 compiled, and made available in the load path during the execution of
7113 @var{exp}---e.g., @code{((guix build utils) (guix build
7114 gnu-build-system))}.
7116 @var{exp} is evaluated in an environment where @code{%outputs} is bound
7117 to a list of output/path pairs, and where @code{%build-inputs} is bound
7118 to a list of string/output-path pairs made from @var{inputs}.
7119 Optionally, @var{env-vars} is a list of string pairs specifying the name
7120 and value of environment variables visible to the builder. The builder
7121 terminates by passing the result of @var{exp} to @code{exit}; thus, when
7122 @var{exp} returns @code{#f}, the build is considered to have failed.
7124 @var{exp} is built using @var{guile-for-build} (a derivation). When
7125 @var{guile-for-build} is omitted or is @code{#f}, the value of the
7126 @code{%guile-for-build} fluid is used instead.
7128 See the @code{derivation} procedure for the meaning of
7129 @var{references-graphs}, @var{allowed-references},
7130 @var{disallowed-references}, @var{local-build?}, and
7131 @var{substitutable?}.
7135 Here's an example of a single-output derivation that creates a directory
7136 containing one file:
7139 (let ((builder '(let ((out (assoc-ref %outputs "out")))
7140 (mkdir out) ; create /gnu/store/@dots{}-goo
7141 (call-with-output-file (string-append out "/test")
7143 (display '(hello guix) p))))))
7144 (build-expression->derivation store "goo" builder))
7146 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
7150 @node The Store Monad
7151 @section The Store Monad
7155 The procedures that operate on the store described in the previous
7156 sections all take an open connection to the build daemon as their first
7157 argument. Although the underlying model is functional, they either have
7158 side effects or depend on the current state of the store.
7160 The former is inconvenient: the connection to the build daemon has to be
7161 carried around in all those functions, making it impossible to compose
7162 functions that do not take that parameter with functions that do. The
7163 latter can be problematic: since store operations have side effects
7164 and/or depend on external state, they have to be properly sequenced.
7166 @cindex monadic values
7167 @cindex monadic functions
7168 This is where the @code{(guix monads)} module comes in. This module
7169 provides a framework for working with @dfn{monads}, and a particularly
7170 useful monad for our uses, the @dfn{store monad}. Monads are a
7171 construct that allows two things: associating ``context'' with values
7172 (in our case, the context is the store), and building sequences of
7173 computations (here computations include accesses to the store). Values
7174 in a monad---values that carry this additional context---are called
7175 @dfn{monadic values}; procedures that return such values are called
7176 @dfn{monadic procedures}.
7178 Consider this ``normal'' procedure:
7181 (define (sh-symlink store)
7182 ;; Return a derivation that symlinks the 'bash' executable.
7183 (let* ((drv (package-derivation store bash))
7184 (out (derivation->output-path drv))
7185 (sh (string-append out "/bin/bash")))
7186 (build-expression->derivation store "sh"
7187 `(symlink ,sh %output))))
7190 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
7191 as a monadic function:
7194 (define (sh-symlink)
7195 ;; Same, but return a monadic value.
7196 (mlet %store-monad ((drv (package->derivation bash)))
7197 (gexp->derivation "sh"
7198 #~(symlink (string-append #$drv "/bin/bash")
7202 There are several things to note in the second version: the @code{store}
7203 parameter is now implicit and is ``threaded'' in the calls to the
7204 @code{package->derivation} and @code{gexp->derivation} monadic
7205 procedures, and the monadic value returned by @code{package->derivation}
7206 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
7208 As it turns out, the call to @code{package->derivation} can even be
7209 omitted since it will take place implicitly, as we will see later
7210 (@pxref{G-Expressions}):
7213 (define (sh-symlink)
7214 (gexp->derivation "sh"
7215 #~(symlink (string-append #$bash "/bin/bash")
7220 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
7221 @c for the funny quote.
7222 Calling the monadic @code{sh-symlink} has no effect. As someone once
7223 said, ``you exit a monad like you exit a building on fire: by running''.
7224 So, to exit the monad and get the desired effect, one must use
7225 @code{run-with-store}:
7228 (run-with-store (open-connection) (sh-symlink))
7229 @result{} /gnu/store/...-sh-symlink
7232 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
7233 new ``meta-commands'' to make it easier to deal with monadic procedures:
7234 @code{run-in-store}, and @code{enter-store-monad}. The former is used
7235 to ``run'' a single monadic value through the store:
7238 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
7239 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7242 The latter enters a recursive REPL, where all the return values are
7243 automatically run through the store:
7246 scheme@@(guile-user)> ,enter-store-monad
7247 store-monad@@(guile-user) [1]> (package->derivation hello)
7248 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7249 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
7250 $3 = "/gnu/store/@dots{}-foo"
7251 store-monad@@(guile-user) [1]> ,q
7252 scheme@@(guile-user)>
7256 Note that non-monadic values cannot be returned in the
7257 @code{store-monad} REPL.
7259 The main syntactic forms to deal with monads in general are provided by
7260 the @code{(guix monads)} module and are described below.
7262 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7263 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7267 @deffn {Scheme Syntax} return @var{val}
7268 Return a monadic value that encapsulates @var{val}.
7271 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7272 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7273 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7274 referred to as ``bind'', but that name denotes an unrelated procedure in
7275 Guile. Thus we use this somewhat cryptic symbol inherited from the
7276 Haskell language.}. There can be one @var{mproc} or several of them, as
7281 (with-monad %state-monad
7283 (lambda (x) (return (+ 1 x)))
7284 (lambda (x) (return (* 2 x)))))
7288 @result{} some-state
7292 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7294 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7296 Bind the variables @var{var} to the monadic values @var{mval} in
7297 @var{body}, which is a sequence of expressions. As with the bind
7298 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7299 value ``contained'' in @var{mval} and making @var{var} refer to that
7300 raw, non-monadic value within the scope of the @var{body}. The form
7301 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7302 @var{val}, as per @code{let}. The binding operations occur in sequence
7303 from left to right. The last expression of @var{body} must be a monadic
7304 expression, and its result will become the result of the @code{mlet} or
7305 @code{mlet*} when run in the @var{monad}.
7307 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7308 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7311 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7312 Bind @var{mexp} and the following monadic expressions in sequence,
7313 returning the result of the last expression. Every expression in the
7314 sequence must be a monadic expression.
7316 This is akin to @code{mlet}, except that the return values of the
7317 monadic expressions are ignored. In that sense, it is analogous to
7318 @code{begin}, but applied to monadic expressions.
7321 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7322 When @var{condition} is true, evaluate the sequence of monadic
7323 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7324 @var{condition} is false, return @code{*unspecified*} in the current
7325 monad. Every expression in the sequence must be a monadic expression.
7328 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7329 When @var{condition} is false, evaluate the sequence of monadic
7330 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7331 @var{condition} is true, return @code{*unspecified*} in the current
7332 monad. Every expression in the sequence must be a monadic expression.
7336 The @code{(guix monads)} module provides the @dfn{state monad}, which
7337 allows an additional value---the state---to be @emph{threaded} through
7338 monadic procedure calls.
7340 @defvr {Scheme Variable} %state-monad
7341 The state monad. Procedures in the state monad can access and change
7342 the state that is threaded.
7344 Consider the example below. The @code{square} procedure returns a value
7345 in the state monad. It returns the square of its argument, but also
7346 increments the current state value:
7350 (mlet %state-monad ((count (current-state)))
7351 (mbegin %state-monad
7352 (set-current-state (+ 1 count))
7355 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7360 When ``run'' through @var{%state-monad}, we obtain that additional state
7361 value, which is the number of @code{square} calls.
7364 @deffn {Monadic Procedure} current-state
7365 Return the current state as a monadic value.
7368 @deffn {Monadic Procedure} set-current-state @var{value}
7369 Set the current state to @var{value} and return the previous state as a
7373 @deffn {Monadic Procedure} state-push @var{value}
7374 Push @var{value} to the current state, which is assumed to be a list,
7375 and return the previous state as a monadic value.
7378 @deffn {Monadic Procedure} state-pop
7379 Pop a value from the current state and return it as a monadic value.
7380 The state is assumed to be a list.
7383 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7384 Run monadic value @var{mval} starting with @var{state} as the initial
7385 state. Return two values: the resulting value, and the resulting state.
7388 The main interface to the store monad, provided by the @code{(guix
7389 store)} module, is as follows.
7391 @defvr {Scheme Variable} %store-monad
7392 The store monad---an alias for @var{%state-monad}.
7394 Values in the store monad encapsulate accesses to the store. When its
7395 effect is needed, a value of the store monad must be ``evaluated'' by
7396 passing it to the @code{run-with-store} procedure (see below.)
7399 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7400 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7401 open store connection.
7404 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7405 Return as a monadic value the absolute file name in the store of the file
7406 containing @var{text}, a string. @var{references} is a list of store items that the
7407 resulting text file refers to; it defaults to the empty list.
7410 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7411 Return as a monadic value the absolute file name in the store of the file
7412 containing @var{data}, a bytevector. @var{references} is a list of store
7413 items that the resulting binary file refers to; it defaults to the empty list.
7416 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7417 [#:recursive? #t] [#:select? (const #t)]
7418 Return the name of @var{file} once interned in the store. Use
7419 @var{name} as its store name, or the basename of @var{file} if
7420 @var{name} is omitted.
7422 When @var{recursive?} is true, the contents of @var{file} are added
7423 recursively; if @var{file} designates a flat file and @var{recursive?}
7424 is true, its contents are added, and its permission bits are kept.
7426 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7427 @var{stat})} for each directory entry, where @var{file} is the entry's
7428 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7429 entries for which @var{select?} does not return true.
7431 The example below adds a file to the store, under two different names:
7434 (run-with-store (open-connection)
7435 (mlet %store-monad ((a (interned-file "README"))
7436 (b (interned-file "README" "LEGU-MIN")))
7437 (return (list a b))))
7439 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7444 The @code{(guix packages)} module exports the following package-related
7447 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7448 [#:system (%current-system)] [#:target #f] @
7451 value in the absolute file name of @var{file} within the @var{output}
7452 directory of @var{package}. When @var{file} is omitted, return the name
7453 of the @var{output} directory of @var{package}. When @var{target} is
7454 true, use it as a cross-compilation target triplet.
7457 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7458 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7459 @var{target} [@var{system}]
7460 Monadic version of @code{package-derivation} and
7461 @code{package-cross-derivation} (@pxref{Defining Packages}).
7466 @section G-Expressions
7468 @cindex G-expression
7469 @cindex build code quoting
7470 So we have ``derivations'', which represent a sequence of build actions
7471 to be performed to produce an item in the store (@pxref{Derivations}).
7472 These build actions are performed when asking the daemon to actually
7473 build the derivations; they are run by the daemon in a container
7474 (@pxref{Invoking guix-daemon}).
7476 @cindex strata of code
7477 It should come as no surprise that we like to write these build actions
7478 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7479 code@footnote{The term @dfn{stratum} in this context was coined by
7480 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7481 Kiselyov, who has written insightful
7482 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7483 on this topic}, refers to this kind of code generation as
7484 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7485 to the daemon, etc.---and the ``build code''---code that actually
7486 performs build actions, such as making directories, invoking
7487 @command{make}, etc.
7489 To describe a derivation and its build actions, one typically needs to
7490 embed build code inside host code. It boils down to manipulating build
7491 code as data, and the homoiconicity of Scheme---code has a direct
7492 representation as data---comes in handy for that. But we need more than
7493 the normal @code{quasiquote} mechanism in Scheme to construct build
7496 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7497 S-expressions adapted to build expressions. G-expressions, or
7498 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7499 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7500 @code{#$}, and @code{#$@@}), which are comparable to
7501 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7502 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7503 GNU Guile Reference Manual}). However, there are major differences:
7507 Gexps are meant to be written to a file and run or manipulated by other
7511 When a high-level object such as a package or derivation is unquoted
7512 inside a gexp, the result is as if its output file name had been
7516 Gexps carry information about the packages or derivations they refer to,
7517 and these dependencies are automatically added as inputs to the build
7518 processes that use them.
7521 @cindex lowering, of high-level objects in gexps
7522 This mechanism is not limited to package and derivation
7523 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7524 derivations or files in the store can be defined,
7525 such that these objects can also be inserted
7526 into gexps. For example, a useful type of high-level objects that can be
7527 inserted in a gexp is ``file-like objects'', which make it easy to
7528 add files to the store and to refer to them in
7529 derivations and such (see @code{local-file} and @code{plain-file}
7532 To illustrate the idea, here is an example of a gexp:
7539 (symlink (string-append #$coreutils "/bin/ls")
7543 This gexp can be passed to @code{gexp->derivation}; we obtain a
7544 derivation that builds a directory containing exactly one symlink to
7545 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7548 (gexp->derivation "the-thing" build-exp)
7551 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7552 substituted to the reference to the @var{coreutils} package in the
7553 actual build code, and @var{coreutils} is automatically made an input to
7554 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7555 output)}) is replaced by a string containing the directory name of the
7556 output of the derivation.
7558 @cindex cross compilation
7559 In a cross-compilation context, it is useful to distinguish between
7560 references to the @emph{native} build of a package---that can run on the
7561 host---versus references to cross builds of a package. To that end, the
7562 @code{#+} plays the same role as @code{#$}, but is a reference to a
7563 native package build:
7566 (gexp->derivation "vi"
7569 (mkdir (string-append #$output "/bin"))
7570 (system* (string-append #+coreutils "/bin/ln")
7572 (string-append #$emacs "/bin/emacs")
7573 (string-append #$output "/bin/vi")))
7574 #:target "mips64el-linux-gnu")
7578 In the example above, the native build of @var{coreutils} is used, so
7579 that @command{ln} can actually run on the host; but then the
7580 cross-compiled build of @var{emacs} is referenced.
7582 @cindex imported modules, for gexps
7583 @findex with-imported-modules
7584 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7585 able to use certain Guile modules from the ``host environment'' in the
7586 gexp, so those modules should be imported in the ``build environment''.
7587 The @code{with-imported-modules} form allows you to express that:
7590 (let ((build (with-imported-modules '((guix build utils))
7592 (use-modules (guix build utils))
7593 (mkdir-p (string-append #$output "/bin"))))))
7594 (gexp->derivation "empty-dir"
7597 (display "success!\n")
7602 In this example, the @code{(guix build utils)} module is automatically
7603 pulled into the isolated build environment of our gexp, such that
7604 @code{(use-modules (guix build utils))} works as expected.
7606 @cindex module closure
7607 @findex source-module-closure
7608 Usually you want the @emph{closure} of the module to be imported---i.e.,
7609 the module itself and all the modules it depends on---rather than just
7610 the module; failing to do that, attempts to use the module will fail
7611 because of missing dependent modules. The @code{source-module-closure}
7612 procedure computes the closure of a module by looking at its source file
7613 headers, which comes in handy in this case:
7616 (use-modules (guix modules)) ;for 'source-module-closure'
7618 (with-imported-modules (source-module-closure
7619 '((guix build utils)
7621 (gexp->derivation "something-with-vms"
7623 (use-modules (guix build utils)
7628 @cindex extensions, for gexps
7629 @findex with-extensions
7630 In the same vein, sometimes you want to import not just pure-Scheme
7631 modules, but also ``extensions'' such as Guile bindings to C libraries
7632 or other ``full-blown'' packages. Say you need the @code{guile-json}
7633 package available on the build side, here's how you would do it:
7636 (use-modules (gnu packages guile)) ;for 'guile-json'
7638 (with-extensions (list guile-json)
7639 (gexp->derivation "something-with-json"
7641 (use-modules (json))
7645 The syntactic form to construct gexps is summarized below.
7647 @deffn {Scheme Syntax} #~@var{exp}
7648 @deffnx {Scheme Syntax} (gexp @var{exp})
7649 Return a G-expression containing @var{exp}. @var{exp} may contain one
7650 or more of the following forms:
7654 @itemx (ungexp @var{obj})
7655 Introduce a reference to @var{obj}. @var{obj} may have one of the
7656 supported types, for example a package or a
7657 derivation, in which case the @code{ungexp} form is replaced by its
7658 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7660 If @var{obj} is a list, it is traversed and references to supported
7661 objects are substituted similarly.
7663 If @var{obj} is another gexp, its contents are inserted and its
7664 dependencies are added to those of the containing gexp.
7666 If @var{obj} is another kind of object, it is inserted as is.
7668 @item #$@var{obj}:@var{output}
7669 @itemx (ungexp @var{obj} @var{output})
7670 This is like the form above, but referring explicitly to the
7671 @var{output} of @var{obj}---this is useful when @var{obj} produces
7672 multiple outputs (@pxref{Packages with Multiple Outputs}).
7675 @itemx #+@var{obj}:output
7676 @itemx (ungexp-native @var{obj})
7677 @itemx (ungexp-native @var{obj} @var{output})
7678 Same as @code{ungexp}, but produces a reference to the @emph{native}
7679 build of @var{obj} when used in a cross compilation context.
7681 @item #$output[:@var{output}]
7682 @itemx (ungexp output [@var{output}])
7683 Insert a reference to derivation output @var{output}, or to the main
7684 output when @var{output} is omitted.
7686 This only makes sense for gexps passed to @code{gexp->derivation}.
7689 @itemx (ungexp-splicing @var{lst})
7690 Like the above, but splices the contents of @var{lst} inside the
7694 @itemx (ungexp-native-splicing @var{lst})
7695 Like the above, but refers to native builds of the objects listed in
7700 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7701 of the @code{gexp?} type (see below.)
7704 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7705 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7706 in their execution environment.
7708 Each item in @var{modules} can be the name of a module, such as
7709 @code{(guix build utils)}, or it can be a module name, followed by an
7710 arrow, followed by a file-like object:
7713 `((guix build utils)
7715 ((guix config) => ,(scheme-file "config.scm"
7716 #~(define-module @dots{}))))
7720 In the example above, the first two modules are taken from the search
7721 path, and the last one is created from the given file-like object.
7723 This form has @emph{lexical} scope: it has an effect on the gexps
7724 directly defined in @var{body}@dots{}, but not on those defined, say, in
7725 procedures called from @var{body}@dots{}.
7728 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7729 Mark the gexps defined in @var{body}@dots{} as requiring
7730 @var{extensions} in their build and execution environment.
7731 @var{extensions} is typically a list of package objects such as those
7732 defined in the @code{(gnu packages guile)} module.
7734 Concretely, the packages listed in @var{extensions} are added to the
7735 load path while compiling imported modules in @var{body}@dots{}; they
7736 are also added to the load path of the gexp returned by
7740 @deffn {Scheme Procedure} gexp? @var{obj}
7741 Return @code{#t} if @var{obj} is a G-expression.
7744 G-expressions are meant to be written to disk, either as code building
7745 some derivation, or as plain files in the store. The monadic procedures
7746 below allow you to do that (@pxref{The Store Monad}, for more
7747 information about monads.)
7749 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7750 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7751 [#:hash #f] [#:hash-algo #f] @
7752 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7753 [#:module-path @var{%load-path}] @
7754 [#:effective-version "2.2"] @
7755 [#:references-graphs #f] [#:allowed-references #f] @
7756 [#:disallowed-references #f] @
7757 [#:leaked-env-vars #f] @
7758 [#:script-name (string-append @var{name} "-builder")] @
7759 [#:deprecation-warnings #f] @
7760 [#:local-build? #f] [#:substitutable? #t] @
7761 [#:properties '()] [#:guile-for-build #f]
7762 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7763 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7764 stored in a file called @var{script-name}. When @var{target} is true,
7765 it is used as the cross-compilation target triplet for packages referred
7768 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7770 make @var{modules} available in the evaluation context of @var{exp};
7771 @var{modules} is a list of names of Guile modules searched in
7772 @var{module-path} to be copied in the store, compiled, and made available in
7773 the load path during the execution of @var{exp}---e.g., @code{((guix
7774 build utils) (guix build gnu-build-system))}.
7776 @var{effective-version} determines the string to use when adding extensions of
7777 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7779 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7782 When @var{references-graphs} is true, it must be a list of tuples of one of the
7786 (@var{file-name} @var{package})
7787 (@var{file-name} @var{package} @var{output})
7788 (@var{file-name} @var{derivation})
7789 (@var{file-name} @var{derivation} @var{output})
7790 (@var{file-name} @var{store-item})
7793 The right-hand-side of each element of @var{references-graphs} is automatically made
7794 an input of the build process of @var{exp}. In the build environment, each
7795 @var{file-name} contains the reference graph of the corresponding item, in a simple
7798 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7799 In the latter case, the list denotes store items that the result is allowed to
7800 refer to. Any reference to another store item will lead to a build error.
7801 Similarly for @var{disallowed-references}, which can list items that must not be
7802 referenced by the outputs.
7804 @var{deprecation-warnings} determines whether to show deprecation warnings while
7805 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7807 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7810 @cindex file-like objects
7811 The @code{local-file}, @code{plain-file}, @code{computed-file},
7812 @code{program-file}, and @code{scheme-file} procedures below return
7813 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7814 these objects lead to a file in the store. Consider this G-expression:
7817 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7818 #$(local-file "/tmp/my-nscd.conf"))
7821 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7822 to the store. Once expanded, for instance @i{via}
7823 @code{gexp->derivation}, the G-expression refers to that copy under
7824 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7825 does not have any effect on what the G-expression does.
7826 @code{plain-file} can be used similarly; it differs in that the file
7827 content is directly passed as a string.
7829 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7830 [#:recursive? #f] [#:select? (const #t)]
7831 Return an object representing local file @var{file} to add to the store;
7832 this object can be used in a gexp. If @var{file} is a literal string
7833 denoting a relative file name, it is looked up relative to the source
7834 file where it appears; if @var{file} is not a literal string, it is
7835 looked up relative to the current working directory at run time.
7836 @var{file} will be added to the store under @var{name}--by default the
7837 base name of @var{file}.
7839 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7840 designates a flat file and @var{recursive?} is true, its contents are added, and its
7841 permission bits are kept.
7843 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7844 @var{stat})} for each directory entry, where @var{file} is the entry's
7845 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7846 entries for which @var{select?} does not return true.
7848 This is the declarative counterpart of the @code{interned-file} monadic
7849 procedure (@pxref{The Store Monad, @code{interned-file}}).
7852 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7853 Return an object representing a text file called @var{name} with the given
7854 @var{content} (a string or a bytevector) to be added to the store.
7856 This is the declarative counterpart of @code{text-file}.
7859 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7860 [#:options '(#:local-build? #t)]
7861 Return an object representing the store item @var{name}, a file or
7862 directory computed by @var{gexp}. @var{options}
7863 is a list of additional arguments to pass to @code{gexp->derivation}.
7865 This is the declarative counterpart of @code{gexp->derivation}.
7868 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7869 [#:guile (default-guile)] [#:module-path %load-path] @
7870 [#:system (%current-system)] [#:target #f]
7871 Return an executable script @var{name} that runs @var{exp} using
7872 @var{guile}, with @var{exp}'s imported modules in its search path.
7873 Look up @var{exp}'s modules in @var{module-path}.
7875 The example below builds a script that simply invokes the @command{ls}
7879 (use-modules (guix gexp) (gnu packages base))
7881 (gexp->script "list-files"
7882 #~(execl #$(file-append coreutils "/bin/ls")
7886 When ``running'' it through the store (@pxref{The Store Monad,
7887 @code{run-with-store}}), we obtain a derivation that produces an
7888 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7891 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7893 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7897 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7898 [#:guile #f] [#:module-path %load-path]
7899 Return an object representing the executable store item @var{name} that
7900 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7901 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7903 This is the declarative counterpart of @code{gexp->script}.
7906 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7907 [#:set-load-path? #t] [#:module-path %load-path] @
7909 [#:guile (default-guile)]
7910 Return a derivation that builds a file @var{name} containing @var{exp}.
7911 When @var{splice?} is true, @var{exp} is considered to be a list of
7912 expressions that will be spliced in the resulting file.
7914 When @var{set-load-path?} is true, emit code in the resulting file to
7915 set @code{%load-path} and @code{%load-compiled-path} to honor
7916 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7919 The resulting file holds references to all the dependencies of @var{exp}
7920 or a subset thereof.
7923 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7924 Return an object representing the Scheme file @var{name} that contains
7927 This is the declarative counterpart of @code{gexp->file}.
7930 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7931 Return as a monadic value a derivation that builds a text file
7932 containing all of @var{text}. @var{text} may list, in addition to
7933 strings, objects of any type that can be used in a gexp: packages,
7934 derivations, local file objects, etc. The resulting store file holds
7935 references to all these.
7937 This variant should be preferred over @code{text-file} anytime the file
7938 to create will reference items from the store. This is typically the
7939 case when building a configuration file that embeds store file names,
7943 (define (profile.sh)
7944 ;; Return the name of a shell script in the store that
7945 ;; initializes the 'PATH' environment variable.
7946 (text-file* "profile.sh"
7947 "export PATH=" coreutils "/bin:"
7948 grep "/bin:" sed "/bin\n"))
7951 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7952 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7953 preventing them from being garbage-collected during its lifetime.
7956 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7957 Return an object representing store file @var{name} containing
7958 @var{text}. @var{text} is a sequence of strings and file-like objects,
7962 (mixed-text-file "profile"
7963 "export PATH=" coreutils "/bin:" grep "/bin")
7966 This is the declarative counterpart of @code{text-file*}.
7969 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7970 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7971 Each item in @var{files} must be a two-element list where the first element is the
7972 file name to use in the new directory, and the second element is a gexp
7973 denoting the target file. Here's an example:
7977 `(("hosts" ,(plain-file "hosts"
7978 "127.0.0.1 localhost"))
7979 ("bashrc" ,(plain-file "bashrc"
7980 "alias ls='ls --color=auto'"))))
7983 This yields an @code{etc} directory containing these two files.
7986 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
7987 Return a directory that is the union of @var{things}, where @var{things} is a list of
7988 file-like objects denoting directories. For example:
7991 (directory-union "guile+emacs" (list guile emacs))
7994 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
7997 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
7998 Return a file-like object that expands to the concatenation of @var{obj}
7999 and @var{suffix}, where @var{obj} is a lowerable object and each
8000 @var{suffix} is a string.
8002 As an example, consider this gexp:
8005 (gexp->script "run-uname"
8006 #~(system* #$(file-append coreutils
8010 The same effect could be achieved with:
8013 (gexp->script "run-uname"
8014 #~(system* (string-append #$coreutils
8018 There is one difference though: in the @code{file-append} case, the
8019 resulting script contains the absolute file name as a string, whereas in
8020 the second case, the resulting script contains a @code{(string-append
8021 @dots{})} expression to construct the file name @emph{at run time}.
8025 Of course, in addition to gexps embedded in ``host'' code, there are
8026 also modules containing build tools. To make it clear that they are
8027 meant to be used in the build stratum, these modules are kept in the
8028 @code{(guix build @dots{})} name space.
8030 @cindex lowering, of high-level objects in gexps
8031 Internally, high-level objects are @dfn{lowered}, using their compiler,
8032 to either derivations or store items. For instance, lowering a package
8033 yields a derivation, and lowering a @code{plain-file} yields a store
8034 item. This is achieved using the @code{lower-object} monadic procedure.
8036 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
8038 Return as a value in @var{%store-monad} the derivation or store item
8039 corresponding to @var{obj} for @var{system}, cross-compiling for
8040 @var{target} if @var{target} is true. @var{obj} must be an object that
8041 has an associated gexp compiler, such as a @code{<package>}.
8044 @node Invoking guix repl
8045 @section Invoking @command{guix repl}
8047 @cindex REPL, read-eval-print loop
8048 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
8049 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
8050 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
8051 command, @command{guix repl} guarantees that all the Guix modules and all its
8052 dependencies are available in the search path. You can use it this way:
8056 scheme@@(guile-user)> ,use (gnu packages base)
8057 scheme@@(guile-user)> coreutils
8058 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
8062 In addition, @command{guix repl} implements a simple machine-readable REPL
8063 protocol for use by @code{(guix inferior)}, a facility to interact with
8064 @dfn{inferiors}, separate processes running a potentially different revision
8067 The available options are as follows:
8070 @item --type=@var{type}
8071 @itemx -t @var{type}
8072 Start a REPL of the given @var{TYPE}, which can be one of the following:
8076 This is default, and it spawns a standard full-featured Guile REPL.
8078 Spawn a REPL that uses the machine-readable protocol. This is the protocol
8079 that the @code{(guix inferior)} module speaks.
8082 @item --listen=@var{endpoint}
8083 By default, @command{guix repl} reads from standard input and writes to
8084 standard output. When this option is passed, it will instead listen for
8085 connections on @var{endpoint}. Here are examples of valid options:
8088 @item --listen=tcp:37146
8089 Accept connections on localhost on port 37146.
8091 @item --listen=unix:/tmp/socket
8092 Accept connections on the Unix-domain socket @file{/tmp/socket}.
8095 @item --load-path=@var{directory}
8096 @itemx -L @var{directory}
8097 Add @var{directory} to the front of the package module search path
8098 (@pxref{Package Modules}).
8100 This allows users to define their own packages and make them visible to
8101 the command-line tool.
8104 Inhibit loading of the @file{~/.guile} file. By default, that
8105 configuration file is loaded when spawning a @code{guile} REPL.
8108 @c *********************************************************************
8112 This section describes Guix command-line utilities. Some of them are
8113 primarily targeted at developers and users who write new package
8114 definitions, while others are more generally useful. They complement
8115 the Scheme programming interface of Guix in a convenient way.
8118 * Invoking guix build:: Building packages from the command line.
8119 * Invoking guix edit:: Editing package definitions.
8120 * Invoking guix download:: Downloading a file and printing its hash.
8121 * Invoking guix hash:: Computing the cryptographic hash of a file.
8122 * Invoking guix import:: Importing package definitions.
8123 * Invoking guix refresh:: Updating package definitions.
8124 * Invoking guix lint:: Finding errors in package definitions.
8125 * Invoking guix size:: Profiling disk usage.
8126 * Invoking guix graph:: Visualizing the graph of packages.
8127 * Invoking guix publish:: Sharing substitutes.
8128 * Invoking guix challenge:: Challenging substitute servers.
8129 * Invoking guix copy:: Copying to and from a remote store.
8130 * Invoking guix container:: Process isolation.
8131 * Invoking guix weather:: Assessing substitute availability.
8132 * Invoking guix processes:: Listing client processes.
8135 @node Invoking guix build
8136 @section Invoking @command{guix build}
8138 @cindex package building
8139 @cindex @command{guix build}
8140 The @command{guix build} command builds packages or derivations and
8141 their dependencies, and prints the resulting store paths. Note that it
8142 does not modify the user's profile---this is the job of the
8143 @command{guix package} command (@pxref{Invoking guix package}). Thus,
8144 it is mainly useful for distribution developers.
8146 The general syntax is:
8149 guix build @var{options} @var{package-or-derivation}@dots{}
8152 As an example, the following command builds the latest versions of Emacs
8153 and of Guile, displays their build logs, and finally displays the
8154 resulting directories:
8157 guix build emacs guile
8160 Similarly, the following command builds all the available packages:
8163 guix build --quiet --keep-going \
8164 `guix package -A | cut -f1,2 --output-delimiter=@@`
8167 @var{package-or-derivation} may be either the name of a package found in
8168 the software distribution such as @code{coreutils} or
8169 @code{coreutils@@8.20}, or a derivation such as
8170 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
8171 package with the corresponding name (and optionally version) is searched
8172 for among the GNU distribution modules (@pxref{Package Modules}).
8174 Alternatively, the @code{--expression} option may be used to specify a
8175 Scheme expression that evaluates to a package; this is useful when
8176 disambiguating among several same-named packages or package variants is
8179 There may be zero or more @var{options}. The available options are
8180 described in the subsections below.
8183 * Common Build Options:: Build options for most commands.
8184 * Package Transformation Options:: Creating variants of packages.
8185 * Additional Build Options:: Options specific to 'guix build'.
8186 * Debugging Build Failures:: Real life packaging experience.
8189 @node Common Build Options
8190 @subsection Common Build Options
8192 A number of options that control the build process are common to
8193 @command{guix build} and other commands that can spawn builds, such as
8194 @command{guix package} or @command{guix archive}. These are the
8199 @item --load-path=@var{directory}
8200 @itemx -L @var{directory}
8201 Add @var{directory} to the front of the package module search path
8202 (@pxref{Package Modules}).
8204 This allows users to define their own packages and make them visible to
8205 the command-line tools.
8209 Keep the build tree of failed builds. Thus, if a build fails, its build
8210 tree is kept under @file{/tmp}, in a directory whose name is shown at
8211 the end of the build log. This is useful when debugging build issues.
8212 @xref{Debugging Build Failures}, for tips and tricks on how to debug
8215 This option implies @option{--no-offload}, and it has no effect when
8216 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
8217 Store, the @code{GUIX_DAEMON_SOCKET} variable}).
8221 Keep going when some of the derivations fail to build; return only once
8222 all the builds have either completed or failed.
8224 The default behavior is to stop as soon as one of the specified
8225 derivations has failed.
8229 Do not build the derivations.
8231 @anchor{fallback-option}
8233 When substituting a pre-built binary fails, fall back to building
8234 packages locally (@pxref{Substitution Failure}).
8236 @item --substitute-urls=@var{urls}
8237 @anchor{client-substitute-urls}
8238 Consider @var{urls} the whitespace-separated list of substitute source
8239 URLs, overriding the default list of URLs of @command{guix-daemon}
8240 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
8242 This means that substitutes may be downloaded from @var{urls}, provided
8243 they are signed by a key authorized by the system administrator
8244 (@pxref{Substitutes}).
8246 When @var{urls} is the empty string, substitutes are effectively
8249 @item --no-substitutes
8250 Do not use substitutes for build products. That is, always build things
8251 locally instead of allowing downloads of pre-built binaries
8252 (@pxref{Substitutes}).
8255 Do not ``graft'' packages. In practice, this means that package updates
8256 available as grafts are not applied. @xref{Security Updates}, for more
8257 information on grafts.
8259 @item --rounds=@var{n}
8260 Build each derivation @var{n} times in a row, and raise an error if
8261 consecutive build results are not bit-for-bit identical.
8263 This is a useful way to detect non-deterministic builds processes.
8264 Non-deterministic build processes are a problem because they make it
8265 practically impossible for users to @emph{verify} whether third-party
8266 binaries are genuine. @xref{Invoking guix challenge}, for more.
8268 Note that, currently, the differing build results are not kept around,
8269 so you will have to manually investigate in case of an error---e.g., by
8270 stashing one of the build results with @code{guix archive --export}
8271 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8275 Do not use offload builds to other machines (@pxref{Daemon Offload
8276 Setup}). That is, always build things locally instead of offloading
8277 builds to remote machines.
8279 @item --max-silent-time=@var{seconds}
8280 When the build or substitution process remains silent for more than
8281 @var{seconds}, terminate it and report a build failure.
8283 By default, the daemon's setting is honored (@pxref{Invoking
8284 guix-daemon, @code{--max-silent-time}}).
8286 @item --timeout=@var{seconds}
8287 Likewise, when the build or substitution process lasts for more than
8288 @var{seconds}, terminate it and report a build failure.
8290 By default, the daemon's setting is honored (@pxref{Invoking
8291 guix-daemon, @code{--timeout}}).
8293 @c Note: This option is actually not part of %standard-build-options but
8294 @c most programs honor it.
8295 @cindex verbosity, of the command-line tools
8296 @cindex build logs, verbosity
8297 @item -v @var{level}
8298 @itemx --verbosity=@var{level}
8299 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8300 output is produced, 1 is for quiet output, and 2 shows all the build log
8301 output on standard error.
8303 @item --cores=@var{n}
8305 Allow the use of up to @var{n} CPU cores for the build. The special
8306 value @code{0} means to use as many CPU cores as available.
8308 @item --max-jobs=@var{n}
8310 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8311 guix-daemon, @code{--max-jobs}}, for details about this option and the
8312 equivalent @command{guix-daemon} option.
8314 @item --debug=@var{level}
8315 Produce debugging output coming from the build daemon. @var{level} must be an
8316 integer between 0 and 5; higher means more verbose output. Setting a level of
8317 4 or more may be helpful when debugging setup issues with the build daemon.
8321 Behind the scenes, @command{guix build} is essentially an interface to
8322 the @code{package-derivation} procedure of the @code{(guix packages)}
8323 module, and to the @code{build-derivations} procedure of the @code{(guix
8324 derivations)} module.
8326 In addition to options explicitly passed on the command line,
8327 @command{guix build} and other @command{guix} commands that support
8328 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
8330 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8331 Users can define this variable to a list of command line options that
8332 will automatically be used by @command{guix build} and other
8333 @command{guix} commands that can perform builds, as in the example
8337 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8340 These options are parsed independently, and the result is appended to
8341 the parsed command-line options.
8345 @node Package Transformation Options
8346 @subsection Package Transformation Options
8348 @cindex package variants
8349 Another set of command-line options supported by @command{guix build}
8350 and also @command{guix package} are @dfn{package transformation
8351 options}. These are options that make it possible to define @dfn{package
8352 variants}---for instance, packages built from different source code.
8353 This is a convenient way to create customized packages on the fly
8354 without having to type in the definitions of package variants
8355 (@pxref{Defining Packages}).
8359 @item --with-source=@var{source}
8360 @itemx --with-source=@var{package}=@var{source}
8361 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8362 Use @var{source} as the source of @var{package}, and @var{version} as
8364 @var{source} must be a file name or a URL, as for @command{guix
8365 download} (@pxref{Invoking guix download}).
8367 When @var{package} is omitted,
8368 it is taken to be the package name specified on the
8369 command line that matches the base of @var{source}---e.g.,
8370 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8371 package is @code{guile}.
8373 Likewise, when @var{version} is omitted, the version string is inferred from
8374 @var{source}; in the previous example, it is @code{2.0.10}.
8376 This option allows users to try out versions of packages other than the
8377 one provided by the distribution. The example below downloads
8378 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8379 the @code{ed} package:
8382 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8385 As a developer, @code{--with-source} makes it easy to test release
8389 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8392 @dots{} or to build from a checkout in a pristine environment:
8395 $ git clone git://git.sv.gnu.org/guix.git
8396 $ guix build guix --with-source=guix@@1.0=./guix
8399 @item --with-input=@var{package}=@var{replacement}
8400 Replace dependency on @var{package} by a dependency on
8401 @var{replacement}. @var{package} must be a package name, and
8402 @var{replacement} must be a package specification such as @code{guile}
8403 or @code{guile@@1.8}.
8405 For instance, the following command builds Guix, but replaces its
8406 dependency on the current stable version of Guile with a dependency on
8407 the legacy version of Guile, @code{guile@@2.0}:
8410 guix build --with-input=guile=guile@@2.0 guix
8413 This is a recursive, deep replacement. So in this example, both
8414 @code{guix} and its dependency @code{guile-json} (which also depends on
8415 @code{guile}) get rebuilt against @code{guile@@2.0}.
8417 This is implemented using the @code{package-input-rewriting} Scheme
8418 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8420 @item --with-graft=@var{package}=@var{replacement}
8421 This is similar to @code{--with-input} but with an important difference:
8422 instead of rebuilding the whole dependency chain, @var{replacement} is
8423 built and then @dfn{grafted} onto the binaries that were initially
8424 referring to @var{package}. @xref{Security Updates}, for more
8425 information on grafts.
8427 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8428 and all its dependencies, replacing references to the version of GnuTLS
8429 they currently refer to:
8432 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8435 This has the advantage of being much faster than rebuilding everything.
8436 But there is a caveat: it works if and only if @var{package} and
8437 @var{replacement} are strictly compatible---for example, if they provide
8438 a library, the application binary interface (ABI) of those libraries
8439 must be compatible. If @var{replacement} is somehow incompatible with
8440 @var{package}, then the resulting package may be unusable. Use with
8443 @item --with-git-url=@var{package}=@var{url}
8444 @cindex Git, using the latest commit
8445 @cindex latest commit, building
8446 Build @var{package} from the latest commit of the @code{master} branch of the
8447 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8450 For example, the following command builds the NumPy Python library against the
8451 latest commit of the master branch of Python itself:
8454 guix build python-numpy \
8455 --with-git-url=python=https://github.com/python/cpython
8458 This option can also be combined with @code{--with-branch} or
8459 @code{--with-commit} (see below).
8461 @cindex continuous integration
8462 Obviously, since it uses the latest commit of the given branch, the result of
8463 such a command varies over time. Nevertheless it is a convenient way to
8464 rebuild entire software stacks against the latest commit of one or more
8465 packages. This is particularly useful in the context of continuous
8468 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8469 consecutive accesses to the same repository. You may want to clean it up once
8470 in a while to save disk space.
8472 @item --with-branch=@var{package}=@var{branch}
8473 Build @var{package} from the latest commit of @var{branch}. If the
8474 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8475 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8476 repository URL is taken from that @code{source}. Otherwise you have to use
8477 @code{--with-git-url} to specify the URL of the Git repository.
8479 For instance, the following command builds @code{guile-sqlite3} from the
8480 latest commit of its @code{master} branch, and then builds @code{guix} (which
8481 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8482 specific @code{guile-sqlite3} build:
8485 guix build --with-branch=guile-sqlite3=master cuirass
8488 @item --with-commit=@var{package}=@var{commit}
8489 This is similar to @code{--with-branch}, except that it builds from
8490 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8491 Git commit SHA1 identifier or a tag.
8494 @node Additional Build Options
8495 @subsection Additional Build Options
8497 The command-line options presented below are specific to @command{guix
8504 Build quietly, without displaying the build log; this is equivalent to
8505 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8506 (or similar) and can always be retrieved using the @option{--log-file} option.
8508 @item --file=@var{file}
8509 @itemx -f @var{file}
8510 Build the package, derivation, or other file-like object that the code within
8511 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8513 As an example, @var{file} might contain a package definition like this
8514 (@pxref{Defining Packages}):
8517 @include package-hello.scm
8520 @item --manifest=@var{manifest}
8521 @itemx -m @var{manifest}
8522 Build all packages listed in the given @var{manifest}
8523 (@pxref{profile-manifest, @option{--manifest}}).
8525 @item --expression=@var{expr}
8526 @itemx -e @var{expr}
8527 Build the package or derivation @var{expr} evaluates to.
8529 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8530 guile-1.8)}, which unambiguously designates this specific variant of
8531 version 1.8 of Guile.
8533 Alternatively, @var{expr} may be a G-expression, in which case it is used
8534 as a build program passed to @code{gexp->derivation}
8535 (@pxref{G-Expressions}).
8537 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8538 (@pxref{The Store Monad}). The procedure must return a derivation as a
8539 monadic value, which is then passed through @code{run-with-store}.
8543 Build the source derivations of the packages, rather than the packages
8546 For instance, @code{guix build -S gcc} returns something like
8547 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8550 The returned source tarball is the result of applying any patches and
8551 code snippets specified in the package @code{origin} (@pxref{Defining
8554 Note that @command{guix build -S} compiles the sources only of the
8555 specified packages. They do not include the sources of statically
8556 linked dependencies and by themselves are insufficient for reproducing
8560 Fetch and return the source of @var{package-or-derivation} and all their
8561 dependencies, recursively. This is a handy way to obtain a local copy
8562 of all the source code needed to build @var{packages}, allowing you to
8563 eventually build them even without network access. It is an extension
8564 of the @code{--source} option and can accept one of the following
8565 optional argument values:
8569 This value causes the @code{--sources} option to behave in the same way
8570 as the @code{--source} option.
8573 Build the source derivations of all packages, including any source that
8574 might be listed as @code{inputs}. This is the default value.
8577 $ guix build --sources tzdata
8578 The following derivations will be built:
8579 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8580 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8584 Build the source derivations of all packages, as well of all transitive
8585 inputs to the packages. This can be used e.g.@: to
8586 prefetch package source for later offline building.
8589 $ guix build --sources=transitive tzdata
8590 The following derivations will be built:
8591 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8592 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8593 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8594 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8595 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8596 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8602 @item --system=@var{system}
8603 @itemx -s @var{system}
8604 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8605 the system type of the build host. The @command{guix build} command allows
8606 you to repeat this option several times, in which case it builds for all the
8607 specified systems; other commands ignore extraneous @option{-s} options.
8610 The @code{--system} flag is for @emph{native} compilation and must not
8611 be confused with cross-compilation. See @code{--target} below for
8612 information on cross-compilation.
8615 An example use of this is on Linux-based systems, which can emulate
8616 different personalities. For instance, passing
8617 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8618 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8619 to build packages in a complete 32-bit environment.
8622 Building for an @code{armhf-linux} system is unconditionally enabled on
8623 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8624 allow for this functionality, notably the ThunderX.
8627 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8628 is enabled (@pxref{Virtualization Services,
8629 @code{qemu-binfmt-service-type}}), you can build for any system for
8630 which a QEMU @code{binfmt_misc} handler is installed.
8632 Builds for a system other than that of the machine you are using can
8633 also be offloaded to a remote machine of the right architecture.
8634 @xref{Daemon Offload Setup}, for more information on offloading.
8636 @item --target=@var{triplet}
8637 @cindex cross-compilation
8638 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8639 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8640 configuration triplets,, autoconf, Autoconf}).
8642 @anchor{build-check}
8644 @cindex determinism, checking
8645 @cindex reproducibility, checking
8646 Rebuild @var{package-or-derivation}, which are already available in the
8647 store, and raise an error if the build results are not bit-for-bit
8650 This mechanism allows you to check whether previously installed
8651 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8652 of a package is deterministic. @xref{Invoking guix challenge}, for more
8653 background information and tools.
8655 When used in conjunction with @option{--keep-failed}, the differing
8656 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8657 This makes it easy to look for differences between the two results.
8660 @cindex repairing store items
8661 @cindex corruption, recovering from
8662 Attempt to repair the specified store items, if they are corrupt, by
8663 re-downloading or rebuilding them.
8665 This operation is not atomic and thus restricted to @code{root}.
8669 Return the derivation paths, not the output paths, of the given
8672 @item --root=@var{file}
8673 @itemx -r @var{file}
8674 @cindex GC roots, adding
8675 @cindex garbage collector roots, adding
8676 Make @var{file} a symlink to the result, and register it as a garbage
8679 Consequently, the results of this @command{guix build} invocation are
8680 protected from garbage collection until @var{file} is removed. When
8681 that option is omitted, build results are eligible for garbage
8682 collection as soon as the build completes. @xref{Invoking guix gc}, for
8686 @cindex build logs, access
8687 Return the build log file names or URLs for the given
8688 @var{package-or-derivation}, or raise an error if build logs are
8691 This works regardless of how packages or derivations are specified. For
8692 instance, the following invocations are equivalent:
8695 guix build --log-file `guix build -d guile`
8696 guix build --log-file `guix build guile`
8697 guix build --log-file guile
8698 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8701 If a log is unavailable locally, and unless @code{--no-substitutes} is
8702 passed, the command looks for a corresponding log on one of the
8703 substitute servers (as specified with @code{--substitute-urls}.)
8705 So for instance, imagine you want to see the build log of GDB on MIPS,
8706 but you are actually on an @code{x86_64} machine:
8709 $ guix build --log-file gdb -s mips64el-linux
8710 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8713 You can freely access a huge library of build logs!
8716 @node Debugging Build Failures
8717 @subsection Debugging Build Failures
8719 @cindex build failures, debugging
8720 When defining a new package (@pxref{Defining Packages}), you will
8721 probably find yourself spending some time debugging and tweaking the
8722 build until it succeeds. To do that, you need to operate the build
8723 commands yourself in an environment as close as possible to the one the
8726 To that end, the first thing to do is to use the @option{--keep-failed}
8727 or @option{-K} option of @command{guix build}, which will keep the
8728 failed build tree in @file{/tmp} or whatever directory you specified as
8729 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8731 From there on, you can @command{cd} to the failed build tree and source
8732 the @file{environment-variables} file, which contains all the
8733 environment variable definitions that were in place when the build
8734 failed. So let's say you're debugging a build failure in package
8735 @code{foo}; a typical session would look like this:
8739 @dots{} @i{build fails}
8740 $ cd /tmp/guix-build-foo.drv-0
8741 $ source ./environment-variables
8745 Now, you can invoke commands as if you were the daemon (almost) and
8746 troubleshoot your build process.
8748 Sometimes it happens that, for example, a package's tests pass when you
8749 run them manually but they fail when the daemon runs them. This can
8750 happen because the daemon runs builds in containers where, unlike in our
8751 environment above, network access is missing, @file{/bin/sh} does not
8752 exist, etc. (@pxref{Build Environment Setup}).
8754 In such cases, you may need to run inspect the build process from within
8755 a container similar to the one the build daemon creates:
8760 $ cd /tmp/guix-build-foo.drv-0
8761 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8762 [env]# source ./environment-variables
8766 Here, @command{guix environment -C} creates a container and spawns a new
8767 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8768 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8769 the container, which would may find handy while debugging. The
8770 @option{--no-grafts} option makes sure we get the exact same
8771 environment, with ungrafted packages (@pxref{Security Updates}, for more
8774 To get closer to a container like that used by the build daemon, we can
8775 remove @file{/bin/sh}:
8781 (Don't worry, this is harmless: this is all happening in the throw-away
8782 container created by @command{guix environment}.)
8784 The @command{strace} command is probably not in the search path, but we
8788 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8791 In this way, not only you will have reproduced the environment variables
8792 the daemon uses, you will also be running the build process in a container
8793 similar to the one the daemon uses.
8796 @node Invoking guix edit
8797 @section Invoking @command{guix edit}
8799 @cindex @command{guix edit}
8800 @cindex package definition, editing
8801 So many packages, so many source files! The @command{guix edit} command
8802 facilitates the life of users and packagers by pointing their editor at
8803 the source file containing the definition of the specified packages.
8807 guix edit gcc@@4.9 vim
8811 launches the program specified in the @code{VISUAL} or in the
8812 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8815 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8816 have created your own packages on @code{GUIX_PACKAGE_PATH}
8817 (@pxref{Package Modules}), you will be able to edit the package
8818 recipes. In other cases, you will be able to examine the read-only recipes
8819 for packages currently in the store.
8821 Instead of @code{GUIX_PACKAGE_PATH}, the command-line option
8822 @code{--load-path=@var{directory}} (or in short @code{-L
8823 @var{directory}}) allows you to add @var{directory} to the front of the
8824 package module search path and so make your own packages visible.
8826 @node Invoking guix download
8827 @section Invoking @command{guix download}
8829 @cindex @command{guix download}
8830 @cindex downloading package sources
8831 When writing a package definition, developers typically need to download
8832 a source tarball, compute its SHA256 hash, and write that
8833 hash in the package definition (@pxref{Defining Packages}). The
8834 @command{guix download} tool helps with this task: it downloads a file
8835 from the given URI, adds it to the store, and prints both its file name
8836 in the store and its SHA256 hash.
8838 The fact that the downloaded file is added to the store saves bandwidth:
8839 when the developer eventually tries to build the newly defined package
8840 with @command{guix build}, the source tarball will not have to be
8841 downloaded again because it is already in the store. It is also a
8842 convenient way to temporarily stash files, which may be deleted
8843 eventually (@pxref{Invoking guix gc}).
8845 The @command{guix download} command supports the same URIs as used in
8846 package definitions. In particular, it supports @code{mirror://} URIs.
8847 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8848 Guile bindings for GnuTLS are available in the user's environment; when
8849 they are not available, an error is raised. @xref{Guile Preparations,
8850 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8851 GnuTLS-Guile}, for more information.
8853 @command{guix download} verifies HTTPS server certificates by loading
8854 the certificates of X.509 authorities from the directory pointed to by
8855 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8856 Certificates}), unless @option{--no-check-certificate} is used.
8858 The following options are available:
8861 @item --format=@var{fmt}
8863 Write the hash in the format specified by @var{fmt}. For more
8864 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8866 @item --no-check-certificate
8867 Do not validate the X.509 certificates of HTTPS servers.
8869 When using this option, you have @emph{absolutely no guarantee} that you
8870 are communicating with the authentic server responsible for the given
8871 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8873 @item --output=@var{file}
8874 @itemx -o @var{file}
8875 Save the downloaded file to @var{file} instead of adding it to the
8879 @node Invoking guix hash
8880 @section Invoking @command{guix hash}
8882 @cindex @command{guix hash}
8883 The @command{guix hash} command computes the SHA256 hash of a file.
8884 It is primarily a convenience tool for anyone contributing to the
8885 distribution: it computes the cryptographic hash of a file, which can be
8886 used in the definition of a package (@pxref{Defining Packages}).
8888 The general syntax is:
8891 guix hash @var{option} @var{file}
8894 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8895 hash of data read from standard input. @command{guix hash} has the
8900 @item --format=@var{fmt}
8902 Write the hash in the format specified by @var{fmt}.
8904 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8905 (@code{hex} and @code{hexadecimal} can be used as well).
8907 If the @option{--format} option is not specified, @command{guix hash}
8908 will output the hash in @code{nix-base32}. This representation is used
8909 in the definitions of packages.
8913 Compute the hash on @var{file} recursively.
8915 In this case, the hash is computed on an archive containing @var{file},
8916 including its children if it is a directory. Some of the metadata of
8917 @var{file} is part of the archive; for instance, when @var{file} is a
8918 regular file, the hash is different depending on whether @var{file} is
8919 executable or not. Metadata such as time stamps has no impact on the
8920 hash (@pxref{Invoking guix archive}).
8921 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8926 When combined with @option{--recursive}, exclude version control system
8927 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8930 As an example, here is how you would compute the hash of a Git checkout,
8931 which is useful when using the @code{git-fetch} method (@pxref{origin
8935 $ git clone http://example.org/foo.git
8941 @node Invoking guix import
8942 @section Invoking @command{guix import}
8944 @cindex importing packages
8945 @cindex package import
8946 @cindex package conversion
8947 @cindex Invoking @command{guix import}
8948 The @command{guix import} command is useful for people who would like to
8949 add a package to the distribution with as little work as
8950 possible---a legitimate demand. The command knows of a few
8951 repositories from which it can ``import'' package metadata. The result
8952 is a package definition, or a template thereof, in the format we know
8953 (@pxref{Defining Packages}).
8955 The general syntax is:
8958 guix import @var{importer} @var{options}@dots{}
8961 @var{importer} specifies the source from which to import package
8962 metadata, and @var{options} specifies a package identifier and other
8963 options specific to @var{importer}.
8965 Some of the importers rely on the ability to run the @command{gpgv} command.
8966 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
8969 Currently, the available ``importers'' are:
8973 Import metadata for the given GNU package. This provides a template
8974 for the latest version of that GNU package, including the hash of its
8975 source tarball, and its canonical synopsis and description.
8977 Additional information such as the package dependencies and its
8978 license needs to be figured out manually.
8980 For example, the following command returns a package definition for
8984 guix import gnu hello
8987 Specific command-line options are:
8990 @item --key-download=@var{policy}
8991 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
8992 keys when verifying the package signature. @xref{Invoking guix
8993 refresh, @code{--key-download}}.
8998 Import metadata from the @uref{https://pypi.python.org/, Python Package
8999 Index}. Information is taken from the JSON-formatted description
9000 available at @code{pypi.python.org} and usually includes all the relevant
9001 information, including package dependencies. For maximum efficiency, it
9002 is recommended to install the @command{unzip} utility, so that the
9003 importer can unzip Python wheels and gather data from them.
9005 The command below imports metadata for the @code{itsdangerous} Python
9009 guix import pypi itsdangerous
9015 Traverse the dependency graph of the given upstream package recursively
9016 and generate package expressions for all those packages that are not yet
9022 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
9023 is taken from the JSON-formatted description available at
9024 @code{rubygems.org} and includes most relevant information, including
9025 runtime dependencies. There are some caveats, however. The metadata
9026 doesn't distinguish between synopses and descriptions, so the same string
9027 is used for both fields. Additionally, the details of non-Ruby
9028 dependencies required to build native extensions is unavailable and left
9029 as an exercise to the packager.
9031 The command below imports metadata for the @code{rails} Ruby package:
9034 guix import gem rails
9040 Traverse the dependency graph of the given upstream package recursively
9041 and generate package expressions for all those packages that are not yet
9047 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
9048 Information is taken from the JSON-formatted metadata provided through
9049 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
9050 relevant information, such as module dependencies. License information
9051 should be checked closely. If Perl is available in the store, then the
9052 @code{corelist} utility will be used to filter core modules out of the
9053 list of dependencies.
9055 The command command below imports metadata for the @code{Acme::Boolean}
9059 guix import cpan Acme::Boolean
9064 @cindex Bioconductor
9065 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
9066 central repository for the @uref{https://r-project.org, GNU@tie{}R
9067 statistical and graphical environment}.
9069 Information is extracted from the @code{DESCRIPTION} file of the package.
9071 The command command below imports metadata for the @code{Cairo}
9075 guix import cran Cairo
9078 When @code{--recursive} is added, the importer will traverse the
9079 dependency graph of the given upstream package recursively and generate
9080 package expressions for all those packages that are not yet in Guix.
9082 When @code{--archive=bioconductor} is added, metadata is imported from
9083 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
9084 packages for for the analysis and comprehension of high-throughput
9085 genomic data in bioinformatics.
9087 Information is extracted from the @code{DESCRIPTION} file contained in the
9090 The command below imports metadata for the @code{GenomicRanges}
9094 guix import cran --archive=bioconductor GenomicRanges
9097 Finally, you can also import R packages that have not yet been published on
9098 CRAN or Bioconductor as long as they are in a git repository. Use
9099 @code{--archive=git} followed by the URL of the git repository:
9102 guix import cran --archive=git https://github.com/immunogenomics/harmony
9108 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
9109 comprehensive TeX archive network for TeX packages that are part of the
9110 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
9112 Information about the package is obtained through the XML API provided
9113 by CTAN, while the source code is downloaded from the SVN repository of
9114 the Tex Live project. This is done because the CTAN does not keep
9117 The command command below imports metadata for the @code{fontspec}
9121 guix import texlive fontspec
9124 When @code{--archive=DIRECTORY} is added, the source code is downloaded
9125 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
9126 tree in the TeX Live SVN repository, but from the specified sibling
9127 directory under the same root.
9129 The command below imports metadata for the @code{ifxetex} package from
9130 CTAN while fetching the sources from the directory
9131 @file{texmf/source/generic}:
9134 guix import texlive --archive=generic ifxetex
9138 @cindex JSON, import
9139 Import package metadata from a local JSON file. Consider the following
9140 example package definition in JSON format:
9146 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
9147 "build-system": "gnu",
9148 "home-page": "https://www.gnu.org/software/hello/",
9149 "synopsis": "Hello, GNU world: An example GNU package",
9150 "description": "GNU Hello prints a greeting.",
9151 "license": "GPL-3.0+",
9152 "native-inputs": ["gettext"]
9156 The field names are the same as for the @code{<package>} record
9157 (@xref{Defining Packages}). References to other packages are provided
9158 as JSON lists of quoted package specification strings such as
9159 @code{guile} or @code{guile@@2.0}.
9161 The importer also supports a more explicit source definition using the
9162 common fields for @code{<origin>} records:
9168 "method": "url-fetch",
9169 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
9171 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
9178 The command below reads metadata from the JSON file @code{hello.json}
9179 and outputs a package expression:
9182 guix import json hello.json
9186 Import metadata from a local copy of the source of the
9187 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
9188 relies on the @command{nix-instantiate} command of
9189 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
9190 typically written in a mixture of Nix-language and Bash code. This
9191 command only imports the high-level package structure that is written in
9192 the Nix language. It normally includes all the basic fields of a
9195 When importing a GNU package, the synopsis and descriptions are replaced
9196 by their canonical upstream variant.
9198 Usually, you will first need to do:
9201 export NIX_REMOTE=daemon
9205 so that @command{nix-instantiate} does not try to open the Nix database.
9207 As an example, the command below imports the package definition of
9208 LibreOffice (more precisely, it imports the definition of the package
9209 bound to the @code{libreoffice} top-level attribute):
9212 guix import nix ~/path/to/nixpkgs libreoffice
9217 Import metadata from the Haskell community's central package archive
9218 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
9219 Cabal files and includes all the relevant information, including package
9222 Specific command-line options are:
9227 Read a Cabal file from standard input.
9228 @item --no-test-dependencies
9230 Do not include dependencies required only by the test suites.
9231 @item --cabal-environment=@var{alist}
9232 @itemx -e @var{alist}
9233 @var{alist} is a Scheme alist defining the environment in which the
9234 Cabal conditionals are evaluated. The accepted keys are: @code{os},
9235 @code{arch}, @code{impl} and a string representing the name of a flag.
9236 The value associated with a flag has to be either the symbol
9237 @code{true} or @code{false}. The value associated with other keys
9238 has to conform to the Cabal file format definition. The default value
9239 associated with the keys @code{os}, @code{arch} and @code{impl} is
9240 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
9243 Traverse the dependency graph of the given upstream package recursively
9244 and generate package expressions for all those packages that are not yet
9248 The command below imports metadata for the latest version of the
9249 @code{HTTP} Haskell package without including test dependencies and
9250 specifying the value of the flag @samp{network-uri} as @code{false}:
9253 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
9256 A specific package version may optionally be specified by following the
9257 package name by an at-sign and a version number as in the following example:
9260 guix import hackage mtl@@2.1.3.1
9265 The @code{stackage} importer is a wrapper around the @code{hackage} one.
9266 It takes a package name, looks up the package version included in a
9267 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
9268 release and uses the @code{hackage} importer to retrieve its metadata.
9269 Note that it is up to you to select an LTS release compatible with the
9270 GHC compiler used by Guix.
9272 Specific command-line options are:
9275 @item --no-test-dependencies
9277 Do not include dependencies required only by the test suites.
9278 @item --lts-version=@var{version}
9279 @itemx -l @var{version}
9280 @var{version} is the desired LTS release version. If omitted the latest
9284 Traverse the dependency graph of the given upstream package recursively
9285 and generate package expressions for all those packages that are not yet
9289 The command below imports metadata for the @code{HTTP} Haskell package
9290 included in the LTS Stackage release version 7.18:
9293 guix import stackage --lts-version=7.18 HTTP
9298 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9299 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9301 Specific command-line options are:
9304 @item --archive=@var{repo}
9305 @itemx -a @var{repo}
9306 @var{repo} identifies the archive repository from which to retrieve the
9307 information. Currently the supported repositories and their identifiers
9311 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9312 identifier. This is the default.
9314 Packages from @code{elpa.gnu.org} are signed with one of the keys
9315 contained in the GnuPG keyring at
9316 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9317 @code{emacs} package (@pxref{Package Installation, ELPA package
9318 signatures,, emacs, The GNU Emacs Manual}).
9321 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9322 @code{melpa-stable} identifier.
9325 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9331 Traverse the dependency graph of the given upstream package recursively
9332 and generate package expressions for all those packages that are not yet
9338 Import metadata from the crates.io Rust package repository
9339 @uref{https://crates.io, crates.io}, as in this example:
9342 guix import crate blake2-rfc
9345 The crate importer also allows you to specify a version string:
9348 guix import crate constant-time-eq@@0.1.0
9351 Additional options include:
9356 Traverse the dependency graph of the given upstream package recursively
9357 and generate package expressions for all those packages that are not yet
9364 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9365 repository used by the OCaml community.
9368 The structure of the @command{guix import} code is modular. It would be
9369 useful to have more importers for other package formats, and your help
9370 is welcome here (@pxref{Contributing}).
9372 @node Invoking guix refresh
9373 @section Invoking @command{guix refresh}
9375 @cindex @command {guix refresh}
9376 The primary audience of the @command{guix refresh} command is developers
9377 of the GNU software distribution. By default, it reports any packages
9378 provided by the distribution that are outdated compared to the latest
9379 upstream version, like this:
9383 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9384 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9387 Alternately, one can specify packages to consider, in which case a
9388 warning is emitted for packages that lack an updater:
9391 $ guix refresh coreutils guile guile-ssh
9392 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9393 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9396 @command{guix refresh} browses the upstream repository of each package and determines
9397 the highest version number of the releases therein. The command
9398 knows how to update specific types of packages: GNU packages, ELPA
9399 packages, etc.---see the documentation for @option{--type} below. There
9400 are many packages, though, for which it lacks a method to determine
9401 whether a new upstream release is available. However, the mechanism is
9402 extensible, so feel free to get in touch with us to add a new method!
9407 Consider the packages specified, and all the packages upon which they depend.
9410 $ guix refresh --recursive coreutils
9411 gnu/packages/acl.scm:35:2: warning: no updater for acl
9412 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9413 gnu/packages/xml.scm:68:2: warning: no updater for expat
9414 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9420 Sometimes the upstream name differs from the package name used in Guix,
9421 and @command{guix refresh} needs a little help. Most updaters honor the
9422 @code{upstream-name} property in package definitions, which can be used
9426 (define-public network-manager
9428 (name "network-manager")
9430 (properties '((upstream-name . "NetworkManager")))))
9433 When passed @code{--update}, it modifies distribution source files to
9434 update the version numbers and source tarball hashes of those package
9435 recipes (@pxref{Defining Packages}). This is achieved by downloading
9436 each package's latest source tarball and its associated OpenPGP
9437 signature, authenticating the downloaded tarball against its signature
9438 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
9439 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
9442 key used to sign the tarball is missing from the user's keyring, an
9443 attempt is made to automatically retrieve it from a public key server;
9444 when this is successful, the key is added to the user's keyring; otherwise,
9445 @command{guix refresh} reports an error.
9447 The following options are supported:
9451 @item --expression=@var{expr}
9452 @itemx -e @var{expr}
9453 Consider the package @var{expr} evaluates to.
9455 This is useful to precisely refer to a package, as in this example:
9458 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9461 This command lists the dependents of the ``final'' libc (essentially all
9466 Update distribution source files (package recipes) in place. This is
9467 usually run from a checkout of the Guix source tree (@pxref{Running
9468 Guix Before It Is Installed}):
9471 $ ./pre-inst-env guix refresh -s non-core -u
9474 @xref{Defining Packages}, for more information on package definitions.
9476 @item --select=[@var{subset}]
9477 @itemx -s @var{subset}
9478 Select all the packages in @var{subset}, one of @code{core} or
9481 The @code{core} subset refers to all the packages at the core of the
9482 distribution---i.e., packages that are used to build ``everything
9483 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9484 changing one of these packages in the distribution entails a rebuild of
9485 all the others. Thus, such updates are an inconvenience to users in
9486 terms of build time or bandwidth used to achieve the upgrade.
9488 The @code{non-core} subset refers to the remaining packages. It is
9489 typically useful in cases where an update of the core packages would be
9492 @item --manifest=@var{file}
9493 @itemx -m @var{file}
9494 Select all the packages from the manifest in @var{file}. This is useful to
9495 check if any packages of the user manifest can be updated.
9497 @item --type=@var{updater}
9498 @itemx -t @var{updater}
9499 Select only packages handled by @var{updater} (may be a comma-separated
9500 list of updaters). Currently, @var{updater} may be one of:
9504 the updater for GNU packages;
9506 the updater for GNOME packages;
9508 the updater for KDE packages;
9510 the updater for X.org packages;
9512 the updater for packages hosted on kernel.org;
9514 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9516 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9518 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9520 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9522 the updater for @uref{https://pypi.python.org, PyPI} packages.
9524 the updater for @uref{https://rubygems.org, RubyGems} packages.
9526 the updater for @uref{https://github.com, GitHub} packages.
9528 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9530 the updater for @uref{https://www.stackage.org, Stackage} packages.
9532 the updater for @uref{https://crates.io, Crates} packages.
9534 the updater for @uref{https://launchpad.net, Launchpad} packages.
9537 For instance, the following command only checks for updates of Emacs
9538 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9541 $ guix refresh --type=elpa,cran
9542 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9543 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9548 In addition, @command{guix refresh} can be passed one or more package
9549 names, as in this example:
9552 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9556 The command above specifically updates the @code{emacs} and
9557 @code{idutils} packages. The @code{--select} option would have no
9558 effect in this case.
9560 When considering whether to upgrade a package, it is sometimes
9561 convenient to know which packages would be affected by the upgrade and
9562 should be checked for compatibility. For this the following option may
9563 be used when passing @command{guix refresh} one or more package names:
9567 @item --list-updaters
9569 List available updaters and exit (see @option{--type} above.)
9571 For each updater, display the fraction of packages it covers; at the
9572 end, display the fraction of packages covered by all these updaters.
9574 @item --list-dependent
9576 List top-level dependent packages that would need to be rebuilt as a
9577 result of upgrading one or more packages.
9579 @xref{Invoking guix graph, the @code{reverse-package} type of
9580 @command{guix graph}}, for information on how to visualize the list of
9581 dependents of a package.
9585 Be aware that the @code{--list-dependent} option only
9586 @emph{approximates} the rebuilds that would be required as a result of
9587 an upgrade. More rebuilds might be required under some circumstances.
9590 $ guix refresh --list-dependent flex
9591 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9592 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9595 The command above lists a set of packages that could be built to check
9596 for compatibility with an upgraded @code{flex} package.
9600 @item --list-transitive
9601 List all the packages which one or more packages depend upon.
9604 $ guix refresh --list-transitive flex
9605 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9606 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{}
9611 The command above lists a set of packages which, when changed, would cause
9612 @code{flex} to be rebuilt.
9614 The following options can be used to customize GnuPG operation:
9618 @item --gpg=@var{command}
9619 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9620 for in @code{$PATH}.
9622 @item --keyring=@var{file}
9623 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9624 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9625 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9626 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9627 information on a tool to manipulate keybox files).
9629 When this option is omitted, @command{guix refresh} uses
9630 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9631 signing keys. OpenPGP signatures are checked against keys from this keyring;
9632 missing keys are downloaded to this keyring as well (see
9633 @option{--key-download} below.)
9635 You can export keys from your default GPG keyring into a keybox file using
9636 commands like this one:
9639 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9642 Likewise, you can fetch keys to a specific keybox file like this:
9645 gpg --no-default-keyring --keyring mykeyring.kbx \
9646 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9649 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9650 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9652 @item --key-download=@var{policy}
9653 Handle missing OpenPGP keys according to @var{policy}, which may be one
9658 Always download missing OpenPGP keys from the key server, and add them
9659 to the user's GnuPG keyring.
9662 Never try to download missing OpenPGP keys. Instead just bail out.
9665 When a package signed with an unknown OpenPGP key is encountered, ask
9666 the user whether to download it or not. This is the default behavior.
9669 @item --key-server=@var{host}
9670 Use @var{host} as the OpenPGP key server when importing a public key.
9672 @item --load-path=@var{directory}
9673 Add @var{directory} to the front of the package module search path
9674 (@pxref{Package Modules}).
9676 This allows users to define their own packages and make them visible to
9677 the command-line tools.
9681 The @code{github} updater uses the
9682 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9683 releases. When used repeatedly e.g.@: when refreshing all packages,
9684 GitHub will eventually refuse to answer any further API requests. By
9685 default 60 API requests per hour are allowed, and a full refresh on all
9686 GitHub packages in Guix requires more than this. Authentication with
9687 GitHub through the use of an API token alleviates these limits. To use
9688 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9689 token procured from @uref{https://github.com/settings/tokens} or
9693 @node Invoking guix lint
9694 @section Invoking @command{guix lint}
9696 @cindex @command{guix lint}
9697 @cindex package, checking for errors
9698 The @command{guix lint} command is meant to help package developers avoid
9699 common errors and use a consistent style. It runs a number of checks on
9700 a given set of packages in order to find common mistakes in their
9701 definitions. Available @dfn{checkers} include (see
9702 @code{--list-checkers} for a complete list):
9707 Validate certain typographical and stylistic rules about package
9708 descriptions and synopses.
9710 @item inputs-should-be-native
9711 Identify inputs that should most likely be native inputs.
9717 @itemx source-file-name
9718 Probe @code{home-page} and @code{source} URLs and report those that are
9719 invalid. Suggest a @code{mirror://} URL when applicable. If the
9720 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9721 URL. Check that the source file name is meaningful, e.g.@: is not just a
9722 version number or ``git-checkout'', without a declared @code{file-name}
9723 (@pxref{origin Reference}).
9725 @item source-unstable-tarball
9726 Parse the @code{source} URL to determine if a tarball from GitHub is
9727 autogenerated or if it is a release tarball. Unfortunately GitHub's
9728 autogenerated tarballs are sometimes regenerated.
9731 @cindex Software Heritage, source code archive
9732 @cindex archival of source code, Software Heritage
9733 Checks whether the package's source code is archived at
9734 @uref{https://www.softwareheritage.org, Software Heritage}.
9736 When the source code that is not archived comes from a version-control system
9737 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
9738 ``save'' request so that it eventually archives it. This ensures that the
9739 source will remain available in the long term, and that Guix can fall back to
9740 Software Heritage should the source code disappear from its original host.
9741 The status of recent ``save'' requests can be
9742 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
9744 When source code is a tarball obtained with @code{url-fetch}, simply print a
9745 message when it is not archived. As of this writing, Software Heritage does
9746 not allow requests to save arbitrary tarballs; we are working on ways to
9747 ensure that non-VCS source code is also archived.
9750 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
9751 request rate per IP address}. When the limit is reached, @command{guix lint}
9752 prints a message and the @code{archival} checker stops doing anything until
9753 that limit has been reset.
9756 @cindex security vulnerabilities
9757 @cindex CVE, Common Vulnerabilities and Exposures
9758 Report known vulnerabilities found in the Common Vulnerabilities and
9759 Exposures (CVE) databases of the current and past year
9760 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
9763 To view information about a particular vulnerability, visit pages such as:
9767 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9769 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9773 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9774 @code{CVE-2015-7554}.
9776 Package developers can specify in package recipes the
9777 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
9778 name and version of the package when they differ from the name or version
9779 that Guix uses, as in this example:
9785 ;; CPE calls this package "grub2".
9786 (properties '((cpe-name . "grub2")
9787 (cpe-version . "2.3"))))
9790 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9791 Some entries in the CVE database do not specify which version of a
9792 package they apply to, and would thus ``stick around'' forever. Package
9793 developers who found CVE alerts and verified they can be ignored can
9794 declare them as in this example:
9800 ;; These CVEs no longer apply and can be safely ignored.
9801 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9804 "CVE-2011-5244")))))
9808 Warn about obvious source code formatting issues: trailing white space,
9809 use of tabulations, etc.
9812 The general syntax is:
9815 guix lint @var{options} @var{package}@dots{}
9818 If no package is given on the command line, then all packages are checked.
9819 The @var{options} may be zero or more of the following:
9822 @item --list-checkers
9824 List and describe all the available checkers that will be run on packages
9829 Only enable the checkers specified in a comma-separated list using the
9830 names returned by @code{--list-checkers}.
9832 @item --load-path=@var{directory}
9833 @itemx -L @var{directory}
9834 Add @var{directory} to the front of the package module search path
9835 (@pxref{Package Modules}).
9837 This allows users to define their own packages and make them visible to
9838 the command-line tools.
9842 @node Invoking guix size
9843 @section Invoking @command{guix size}
9846 @cindex package size
9848 @cindex @command{guix size}
9849 The @command{guix size} command helps package developers profile the
9850 disk usage of packages. It is easy to overlook the impact of an
9851 additional dependency added to a package, or the impact of using a
9852 single output for a package that could easily be split (@pxref{Packages
9853 with Multiple Outputs}). Such are the typical issues that
9854 @command{guix size} can highlight.
9856 The command can be passed one or more package specifications
9857 such as @code{gcc@@4.8}
9858 or @code{guile:debug}, or a file name in the store. Consider this
9862 $ guix size coreutils
9863 store item total self
9864 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9865 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9866 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9867 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9868 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9869 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9870 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9871 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9876 The store items listed here constitute the @dfn{transitive closure} of
9877 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9878 would be returned by:
9881 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9884 Here the output shows three columns next to store items. The first column,
9885 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9886 the store item---that is, its own size plus the size of all its
9887 dependencies. The next column, labeled ``self'', shows the size of the
9888 item itself. The last column shows the ratio of the size of the item
9889 itself to the space occupied by all the items listed here.
9891 In this example, we see that the closure of Coreutils weighs in at
9892 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9893 libraries. (That libc and GCC's libraries represent a large fraction of
9894 the closure is not a problem @i{per se} because they are always available
9895 on the system anyway.)
9897 When the package(s) passed to @command{guix size} are available in the
9898 store@footnote{More precisely, @command{guix size} looks for the
9899 @emph{ungrafted} variant of the given package(s), as returned by
9900 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9901 for information on grafts.}, @command{guix size} queries the daemon to determine its
9902 dependencies, and measures its size in the store, similar to @command{du
9903 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9906 When the given packages are @emph{not} in the store, @command{guix size}
9907 reports information based on the available substitutes
9908 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9909 store items that are not even on disk, only available remotely.
9911 You can also specify several package names:
9914 $ guix size coreutils grep sed bash
9915 store item total self
9916 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9917 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9918 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9919 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9925 In this example we see that the combination of the four packages takes
9926 102.3@tie{}MiB in total, which is much less than the sum of each closure
9927 since they have a lot of dependencies in common.
9929 The available options are:
9933 @item --substitute-urls=@var{urls}
9934 Use substitute information from @var{urls}.
9935 @xref{client-substitute-urls, the same option for @code{guix build}}.
9937 @item --sort=@var{key}
9938 Sort lines according to @var{key}, one of the following options:
9942 the size of each item (the default);
9944 the total size of the item's closure.
9947 @item --map-file=@var{file}
9948 Write a graphical map of disk usage in PNG format to @var{file}.
9950 For the example above, the map looks like this:
9952 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
9953 produced by @command{guix size}}
9955 This option requires that
9956 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
9957 installed and visible in Guile's module search path. When that is not
9958 the case, @command{guix size} fails as it tries to load it.
9960 @item --system=@var{system}
9961 @itemx -s @var{system}
9962 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
9964 @item --load-path=@var{directory}
9965 @itemx -L @var{directory}
9966 Add @var{directory} to the front of the package module search path
9967 (@pxref{Package Modules}).
9969 This allows users to define their own packages and make them visible to
9970 the command-line tools.
9973 @node Invoking guix graph
9974 @section Invoking @command{guix graph}
9977 @cindex @command{guix graph}
9978 @cindex package dependencies
9979 Packages and their dependencies form a @dfn{graph}, specifically a
9980 directed acyclic graph (DAG). It can quickly become difficult to have a
9981 mental model of the package DAG, so the @command{guix graph} command
9982 provides a visual representation of the DAG. By default,
9983 @command{guix graph} emits a DAG representation in the input format of
9984 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
9985 directly to the @command{dot} command of Graphviz. It can also emit an
9986 HTML page with embedded JavaScript code to display a ``chord diagram''
9987 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
9988 emit Cypher queries to construct a graph in a graph database supporting
9989 the @uref{https://www.opencypher.org/, openCypher} query language.
9990 The general syntax is:
9993 guix graph @var{options} @var{package}@dots{}
9996 For example, the following command generates a PDF file representing the
9997 package DAG for the GNU@tie{}Core Utilities, showing its build-time
10001 guix graph coreutils | dot -Tpdf > dag.pdf
10004 The output looks like this:
10006 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
10008 Nice little graph, no?
10010 But there is more than one graph! The one above is concise: it is the
10011 graph of package objects, omitting implicit inputs such as GCC, libc,
10012 grep, etc. It is often useful to have such a concise graph, but
10013 sometimes one may want to see more details. @command{guix graph} supports
10014 several types of graphs, allowing you to choose the level of detail:
10018 This is the default type used in the example above. It shows the DAG of
10019 package objects, excluding implicit dependencies. It is concise, but
10020 filters out many details.
10022 @item reverse-package
10023 This shows the @emph{reverse} DAG of packages. For example:
10026 guix graph --type=reverse-package ocaml
10029 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
10030 you are also interested in cases where OCaml is an implicit dependency, see
10031 @code{reverse-bag} below.)
10033 Note that for core packages this can yield huge graphs. If all you want
10034 is to know the number of packages that depend on a given package, use
10035 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
10036 @option{--list-dependent}}).
10039 This is the package DAG, @emph{including} implicit inputs.
10041 For instance, the following command:
10044 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
10047 ...@: yields this bigger graph:
10049 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
10051 At the bottom of the graph, we see all the implicit inputs of
10052 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
10054 Now, note that the dependencies of these implicit inputs---that is, the
10055 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
10056 here, for conciseness.
10059 Similar to @code{bag-emerged}, but this time including all the bootstrap
10062 @item bag-with-origins
10063 Similar to @code{bag}, but also showing origins and their dependencies.
10066 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
10067 it also takes implicit dependencies into account. For example:
10070 guix graph -t reverse-bag dune
10074 ...@: yields the graph of all packages that depend on Dune, directly or
10075 indirectly. Since Dune is an @emph{implicit} dependency of many packages
10076 @i{via} @code{dune-build-system}, this shows a large number of packages,
10077 whereas @code{reverse-package} would show very few if any.
10080 This is the most detailed representation: It shows the DAG of
10081 derivations (@pxref{Derivations}) and plain store items. Compared to
10082 the above representation, many additional nodes are visible, including
10083 build scripts, patches, Guile modules, etc.
10085 For this type of graph, it is also possible to pass a @file{.drv} file
10086 name instead of a package name, as in:
10089 guix graph -t derivation `guix system build -d my-config.scm`
10093 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
10094 For example, the following command shows the graph for the package
10095 module that defines the @code{guile} package:
10098 guix graph -t module guile | dot -Tpdf > module-graph.pdf
10102 All the types above correspond to @emph{build-time dependencies}. The
10103 following graph type represents the @emph{run-time dependencies}:
10107 This is the graph of @dfn{references} of a package output, as returned
10108 by @command{guix gc --references} (@pxref{Invoking guix gc}).
10110 If the given package output is not available in the store, @command{guix
10111 graph} attempts to obtain dependency information from substitutes.
10113 Here you can also pass a store file name instead of a package name. For
10114 example, the command below produces the reference graph of your profile
10115 (which can be big!):
10118 guix graph -t references `readlink -f ~/.guix-profile`
10122 This is the graph of the @dfn{referrers} of a store item, as returned by
10123 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
10125 This relies exclusively on local information from your store. For
10126 instance, let us suppose that the current Inkscape is available in 10
10127 profiles on your machine; @command{guix graph -t referrers inkscape}
10128 will show a graph rooted at Inkscape and with those 10 profiles linked
10131 It can help determine what is preventing a store item from being garbage
10136 The available options are the following:
10139 @item --type=@var{type}
10140 @itemx -t @var{type}
10141 Produce a graph output of @var{type}, where @var{type} must be one of
10142 the values listed above.
10145 List the supported graph types.
10147 @item --backend=@var{backend}
10148 @itemx -b @var{backend}
10149 Produce a graph using the selected @var{backend}.
10151 @item --list-backends
10152 List the supported graph backends.
10154 Currently, the available backends are Graphviz and d3.js.
10156 @item --expression=@var{expr}
10157 @itemx -e @var{expr}
10158 Consider the package @var{expr} evaluates to.
10160 This is useful to precisely refer to a package, as in this example:
10163 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
10166 @item --system=@var{system}
10167 @itemx -s @var{system}
10168 Display the graph for @var{system}---e.g., @code{i686-linux}.
10170 The package dependency graph is largely architecture-independent, but there
10171 are some architecture-dependent bits that this option allows you to visualize.
10173 @item --load-path=@var{directory}
10174 @itemx -L @var{directory}
10175 Add @var{directory} to the front of the package module search path
10176 (@pxref{Package Modules}).
10178 This allows users to define their own packages and make them visible to
10179 the command-line tools.
10182 On top of that, @command{guix graph} supports all the usual package
10183 transformation options (@pxref{Package Transformation Options}). This
10184 makes it easy to view the effect of a graph-rewriting transformation
10185 such as @option{--with-input}. For example, the command below outputs
10186 the graph of @code{git} once @code{openssl} has been replaced by
10187 @code{libressl} everywhere in the graph:
10190 guix graph git --with-input=openssl=libressl
10193 So many possibilities, so much fun!
10195 @node Invoking guix publish
10196 @section Invoking @command{guix publish}
10198 @cindex @command{guix publish}
10199 The purpose of @command{guix publish} is to enable users to easily share
10200 their store with others, who can then use it as a substitute server
10201 (@pxref{Substitutes}).
10203 When @command{guix publish} runs, it spawns an HTTP server which allows
10204 anyone with network access to obtain substitutes from it. This means
10205 that any machine running Guix can also act as if it were a build farm,
10206 since the HTTP interface is compatible with Cuirass, the software behind
10207 the @code{@value{SUBSTITUTE-SERVER}} build farm.
10209 For security, each substitute is signed, allowing recipients to check
10210 their authenticity and integrity (@pxref{Substitutes}). Because
10211 @command{guix publish} uses the signing key of the system, which is only
10212 readable by the system administrator, it must be started as root; the
10213 @code{--user} option makes it drop root privileges early on.
10215 The signing key pair must be generated before @command{guix publish} is
10216 launched, using @command{guix archive --generate-key} (@pxref{Invoking
10219 The general syntax is:
10222 guix publish @var{options}@dots{}
10225 Running @command{guix publish} without any additional arguments will
10226 spawn an HTTP server on port 8080:
10232 Once a publishing server has been authorized (@pxref{Invoking guix
10233 archive}), the daemon may download substitutes from it:
10236 guix-daemon --substitute-urls=http://example.org:8080
10239 By default, @command{guix publish} compresses archives on the fly as it
10240 serves them. This ``on-the-fly'' mode is convenient in that it requires
10241 no setup and is immediately available. However, when serving lots of
10242 clients, we recommend using the @option{--cache} option, which enables
10243 caching of the archives before they are sent to clients---see below for
10244 details. The @command{guix weather} command provides a handy way to
10245 check what a server provides (@pxref{Invoking guix weather}).
10247 As a bonus, @command{guix publish} also serves as a content-addressed
10248 mirror for source files referenced in @code{origin} records
10249 (@pxref{origin Reference}). For instance, assuming @command{guix
10250 publish} is running on @code{example.org}, the following URL returns the
10251 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
10252 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
10255 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
10258 Obviously, these URLs only work for files that are in the store; in
10259 other cases, they return 404 (``Not Found'').
10261 @cindex build logs, publication
10262 Build logs are available from @code{/log} URLs like:
10265 http://example.org/log/gwspk@dots{}-guile-2.2.3
10269 When @command{guix-daemon} is configured to save compressed build logs,
10270 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
10271 URLs return the compressed log as-is, with an appropriate
10272 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
10273 running @command{guix-daemon} with @code{--log-compression=gzip} since
10274 Web browsers can automatically decompress it, which is not the case with
10277 The following options are available:
10280 @item --port=@var{port}
10281 @itemx -p @var{port}
10282 Listen for HTTP requests on @var{port}.
10284 @item --listen=@var{host}
10285 Listen on the network interface for @var{host}. The default is to
10286 accept connections from any interface.
10288 @item --user=@var{user}
10289 @itemx -u @var{user}
10290 Change privileges to @var{user} as soon as possible---i.e., once the
10291 server socket is open and the signing key has been read.
10293 @item --compression[=@var{method}[:@var{level}]]
10294 @itemx -C [@var{method}[:@var{level}]]
10295 Compress data using the given @var{method} and @var{level}. @var{method} is
10296 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
10299 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
10300 to different compression levels: 1 is the fastest, and 9 is the best
10301 (CPU-intensive). The default is 3.
10303 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
10304 increase in CPU usage; see
10305 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
10308 Unless @option{--cache} is used, compression occurs on the fly and
10309 the compressed streams are not
10310 cached. Thus, to reduce load on the machine that runs @command{guix
10311 publish}, it may be a good idea to choose a low compression level, to
10312 run @command{guix publish} behind a caching proxy, or to use
10313 @option{--cache}. Using @option{--cache} has the advantage that it
10314 allows @command{guix publish} to add @code{Content-Length} HTTP header
10317 This option can be repeated, in which case every substitute gets compressed
10318 using all the selected methods, and all of them are advertised. This is
10319 useful when users may not support all the compression methods: they can select
10320 the one they support.
10322 @item --cache=@var{directory}
10323 @itemx -c @var{directory}
10324 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
10325 and only serve archives that are in cache.
10327 When this option is omitted, archives and meta-data are created
10328 on-the-fly. This can reduce the available bandwidth, especially when
10329 compression is enabled, since this may become CPU-bound. Another
10330 drawback of the default mode is that the length of archives is not known
10331 in advance, so @command{guix publish} does not add a
10332 @code{Content-Length} HTTP header to its responses, which in turn
10333 prevents clients from knowing the amount of data being downloaded.
10335 Conversely, when @option{--cache} is used, the first request for a store
10336 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10337 background process to @dfn{bake} the archive---computing its
10338 @code{.narinfo} and compressing the archive, if needed. Once the
10339 archive is cached in @var{directory}, subsequent requests succeed and
10340 are served directly from the cache, which guarantees that clients get
10341 the best possible bandwidth.
10343 The ``baking'' process is performed by worker threads. By default, one
10344 thread per CPU core is created, but this can be customized. See
10345 @option{--workers} below.
10347 When @option{--ttl} is used, cached entries are automatically deleted
10348 when they have expired.
10350 @item --workers=@var{N}
10351 When @option{--cache} is used, request the allocation of @var{N} worker
10352 threads to ``bake'' archives.
10354 @item --ttl=@var{ttl}
10355 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10356 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10357 days, @code{1m} means 1 month, and so on.
10359 This allows the user's Guix to keep substitute information in cache for
10360 @var{ttl}. However, note that @code{guix publish} does not itself
10361 guarantee that the store items it provides will indeed remain available
10362 for as long as @var{ttl}.
10364 Additionally, when @option{--cache} is used, cached entries that have
10365 not been accessed for @var{ttl} and that no longer have a corresponding
10366 item in the store, may be deleted.
10368 @item --nar-path=@var{path}
10369 Use @var{path} as the prefix for the URLs of ``nar'' files
10370 (@pxref{Invoking guix archive, normalized archives}).
10372 By default, nars are served at a URL such as
10373 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
10374 change the @code{/nar} part to @var{path}.
10376 @item --public-key=@var{file}
10377 @itemx --private-key=@var{file}
10378 Use the specific @var{file}s as the public/private key pair used to sign
10379 the store items being published.
10381 The files must correspond to the same key pair (the private key is used
10382 for signing and the public key is merely advertised in the signature
10383 metadata). They must contain keys in the canonical s-expression format
10384 as produced by @command{guix archive --generate-key} (@pxref{Invoking
10385 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
10386 @file{/etc/guix/signing-key.sec} are used.
10388 @item --repl[=@var{port}]
10389 @itemx -r [@var{port}]
10390 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
10391 Reference Manual}) on @var{port} (37146 by default). This is used
10392 primarily for debugging a running @command{guix publish} server.
10395 Enabling @command{guix publish} on Guix System is a one-liner: just
10396 instantiate a @code{guix-publish-service-type} service in the @code{services} field
10397 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
10398 @code{guix-publish-service-type}}).
10400 If you are instead running Guix on a ``foreign distro'', follow these
10405 If your host distro uses the systemd init system:
10408 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
10409 /etc/systemd/system/
10410 # systemctl start guix-publish && systemctl enable guix-publish
10414 If your host distro uses the Upstart init system:
10417 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
10418 # start guix-publish
10422 Otherwise, proceed similarly with your distro's init system.
10425 @node Invoking guix challenge
10426 @section Invoking @command{guix challenge}
10428 @cindex reproducible builds
10429 @cindex verifiable builds
10430 @cindex @command{guix challenge}
10432 Do the binaries provided by this server really correspond to the source
10433 code it claims to build? Is a package build process deterministic?
10434 These are the questions the @command{guix challenge} command attempts to
10437 The former is obviously an important question: Before using a substitute
10438 server (@pxref{Substitutes}), one had better @emph{verify} that it
10439 provides the right binaries, and thus @emph{challenge} it. The latter
10440 is what enables the former: If package builds are deterministic, then
10441 independent builds of the package should yield the exact same result,
10442 bit for bit; if a server provides a binary different from the one
10443 obtained locally, it may be either corrupt or malicious.
10445 We know that the hash that shows up in @file{/gnu/store} file names is
10446 the hash of all the inputs of the process that built the file or
10447 directory---compilers, libraries, build scripts,
10448 etc. (@pxref{Introduction}). Assuming deterministic build processes,
10449 one store file name should map to exactly one build output.
10450 @command{guix challenge} checks whether there is, indeed, a single
10451 mapping by comparing the build outputs of several independent builds of
10452 any given store item.
10454 The command output looks like this:
10457 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10458 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
10459 updating list of substitutes from 'https://guix.example.org'... 100.0%
10460 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
10461 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10462 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10463 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
10465 /lib/libcrypto.so.1.1
10468 /gnu/store/@dots{}-git-2.5.0 contents differ:
10469 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
10470 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
10471 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
10473 /libexec/git-core/git-fsck
10475 /gnu/store/@dots{}-pius-2.1.1 contents differ:
10476 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10477 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10478 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
10480 /share/man/man1/pius.1.gz
10484 6,406 store items were analyzed:
10485 - 4,749 (74.1%) were identical
10486 - 525 (8.2%) differed
10487 - 1,132 (17.7%) were inconclusive
10491 In this example, @command{guix challenge} first scans the store to
10492 determine the set of locally-built derivations---as opposed to store
10493 items that were downloaded from a substitute server---and then queries
10494 all the substitute servers. It then reports those store items for which
10495 the servers obtained a result different from the local build.
10497 @cindex non-determinism, in package builds
10498 As an example, @code{guix.example.org} always gets a different answer.
10499 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10500 case of Git. This might indicate that the build process of Git is
10501 non-deterministic, meaning that its output varies as a function of
10502 various things that Guix does not fully control, in spite of building
10503 packages in isolated environments (@pxref{Features}). Most common
10504 sources of non-determinism include the addition of timestamps in build
10505 results, the inclusion of random numbers, and directory listings sorted
10506 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
10509 To find out what is wrong with this Git binary, the easiest approach is
10513 guix challenge git \
10514 --diff=diffoscope \
10515 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10518 This automatically invokes @command{diffoscope}, which displays detailed
10519 information about files that differ.
10521 Alternately, we can do something along these lines (@pxref{Invoking guix
10525 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0 \
10526 | guix archive -x /tmp/git
10527 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
10530 This command shows the difference between the files resulting from the
10531 local build, and the files resulting from the build on
10532 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
10533 diffutils, Comparing and Merging Files}). The @command{diff} command
10534 works great for text files. When binary files differ, a better option
10535 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
10536 visualize differences for all kinds of files.
10538 Once you have done that work, you can tell whether the differences are due
10539 to a non-deterministic build process or to a malicious server. We try
10540 hard to remove sources of non-determinism in packages to make it easier
10541 to verify substitutes, but of course, this is a process that
10542 involves not just Guix, but a large part of the free software community.
10543 In the meantime, @command{guix challenge} is one tool to help address
10546 If you are writing packages for Guix, you are encouraged to check
10547 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
10548 same build result as you did with:
10551 $ guix challenge @var{package}
10555 where @var{package} is a package specification such as
10556 @code{guile@@2.0} or @code{glibc:debug}.
10558 The general syntax is:
10561 guix challenge @var{options} [@var{packages}@dots{}]
10564 When a difference is found between the hash of a locally-built item and
10565 that of a server-provided substitute, or among substitutes provided by
10566 different servers, the command displays it as in the example above and
10567 its exit code is 2 (other non-zero exit codes denote other kinds of
10570 The one option that matters is:
10574 @item --substitute-urls=@var{urls}
10575 Consider @var{urls} the whitespace-separated list of substitute source
10576 URLs to compare to.
10578 @item --diff=@var{mode}
10579 Upon mismatches, show differences according to @var{mode}, one of:
10582 @item @code{simple} (the default)
10583 Show the list of files that differ.
10585 @item @code{diffoscope}
10586 @itemx @var{command}
10587 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
10588 two directories whose contents do not match.
10590 When @var{command} is an absolute file name, run @var{command} instead
10594 Do not show further details about the differences.
10597 Thus, unless @code{--diff=none} is passed, @command{guix challenge}
10598 downloads the store items from the given substitute servers so that it
10603 Show details about matches (identical contents) in addition to
10604 information about mismatches.
10608 @node Invoking guix copy
10609 @section Invoking @command{guix copy}
10611 @cindex copy, of store items, over SSH
10612 @cindex SSH, copy of store items
10613 @cindex sharing store items across machines
10614 @cindex transferring store items across machines
10615 The @command{guix copy} command copies items from the store of one
10616 machine to that of another machine over a secure shell (SSH)
10617 connection@footnote{This command is available only when Guile-SSH was
10618 found. @xref{Requirements}, for details.}. For example, the following
10619 command copies the @code{coreutils} package, the user's profile, and all
10620 their dependencies over to @var{host}, logged in as @var{user}:
10623 guix copy --to=@var{user}@@@var{host} \
10624 coreutils `readlink -f ~/.guix-profile`
10627 If some of the items to be copied are already present on @var{host},
10628 they are not actually sent.
10630 The command below retrieves @code{libreoffice} and @code{gimp} from
10631 @var{host}, assuming they are available there:
10634 guix copy --from=@var{host} libreoffice gimp
10637 The SSH connection is established using the Guile-SSH client, which is
10638 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10639 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10641 The key used to sign items that are sent must be accepted by the remote
10642 machine. Likewise, the key used by the remote machine to sign items you
10643 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10644 own daemon. @xref{Invoking guix archive}, for more information about
10645 store item authentication.
10647 The general syntax is:
10650 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10653 You must always specify one of the following options:
10656 @item --to=@var{spec}
10657 @itemx --from=@var{spec}
10658 Specify the host to send to or receive from. @var{spec} must be an SSH
10659 spec such as @code{example.org}, @code{charlie@@example.org}, or
10660 @code{charlie@@example.org:2222}.
10663 The @var{items} can be either package names, such as @code{gimp}, or
10664 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10666 When specifying the name of a package to send, it is first built if
10667 needed, unless @option{--dry-run} was specified. Common build options
10668 are supported (@pxref{Common Build Options}).
10671 @node Invoking guix container
10672 @section Invoking @command{guix container}
10674 @cindex @command{guix container}
10676 As of version @value{VERSION}, this tool is experimental. The interface
10677 is subject to radical change in the future.
10680 The purpose of @command{guix container} is to manipulate processes
10681 running within an isolated environment, commonly known as a
10682 ``container'', typically created by the @command{guix environment}
10683 (@pxref{Invoking guix environment}) and @command{guix system container}
10684 (@pxref{Invoking guix system}) commands.
10686 The general syntax is:
10689 guix container @var{action} @var{options}@dots{}
10692 @var{action} specifies the operation to perform with a container, and
10693 @var{options} specifies the context-specific arguments for the action.
10695 The following actions are available:
10699 Execute a command within the context of a running container.
10704 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10707 @var{pid} specifies the process ID of the running container.
10708 @var{program} specifies an executable file name within the root file
10709 system of the container. @var{arguments} are the additional options that
10710 will be passed to @var{program}.
10712 The following command launches an interactive login shell inside a
10713 Guix system container, started by @command{guix system container}, and whose
10714 process ID is 9001:
10717 guix container exec 9001 /run/current-system/profile/bin/bash --login
10720 Note that the @var{pid} cannot be the parent process of a container. It
10721 must be PID 1 of the container or one of its child processes.
10725 @node Invoking guix weather
10726 @section Invoking @command{guix weather}
10728 Occasionally you're grumpy because substitutes are lacking and you end
10729 up building packages by yourself (@pxref{Substitutes}). The
10730 @command{guix weather} command reports on substitute availability on the
10731 specified servers so you can have an idea of whether you'll be grumpy
10732 today. It can sometimes be useful info as a user, but it is primarily
10733 useful to people running @command{guix publish} (@pxref{Invoking guix
10736 @cindex statistics, for substitutes
10737 @cindex availability of substitutes
10738 @cindex substitute availability
10739 @cindex weather, substitute availability
10740 Here's a sample run:
10743 $ guix weather --substitute-urls=https://guix.example.org
10744 computing 5,872 package derivations for x86_64-linux...
10745 looking for 6,128 store items on https://guix.example.org..
10746 updating list of substitutes from 'https://guix.example.org'... 100.0%
10747 https://guix.example.org
10748 43.4% substitutes available (2,658 out of 6,128)
10749 7,032.5 MiB of nars (compressed)
10750 19,824.2 MiB on disk (uncompressed)
10751 0.030 seconds per request (182.9 seconds in total)
10752 33.5 requests per second
10754 9.8% (342 out of 3,470) of the missing items are queued
10756 x86_64-linux: 518 (59.7%)
10757 i686-linux: 221 (25.5%)
10758 aarch64-linux: 128 (14.8%)
10759 build rate: 23.41 builds per hour
10760 x86_64-linux: 11.16 builds per hour
10761 i686-linux: 6.03 builds per hour
10762 aarch64-linux: 6.41 builds per hour
10765 @cindex continuous integration, statistics
10766 As you can see, it reports the fraction of all the packages for which
10767 substitutes are available on the server---regardless of whether
10768 substitutes are enabled, and regardless of whether this server's signing
10769 key is authorized. It also reports the size of the compressed archives
10770 (``nars'') provided by the server, the size the corresponding store
10771 items occupy in the store (assuming deduplication is turned off), and
10772 the server's throughput. The second part gives continuous integration
10773 (CI) statistics, if the server supports it. In addition, using the
10774 @option{--coverage} option, @command{guix weather} can list ``important''
10775 package substitutes missing on the server (see below).
10777 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10778 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10779 challenge}, it ignores signatures on those substitutes, which is
10780 innocuous since the command only gathers statistics and cannot install
10783 The general syntax is:
10786 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10789 When @var{packages} is omitted, @command{guix weather} checks the availability
10790 of substitutes for @emph{all} the packages, or for those specified with
10791 @option{--manifest}; otherwise it only considers the specified packages. It
10792 is also possible to query specific system types with @option{--system}. The
10793 available options are listed below.
10796 @item --substitute-urls=@var{urls}
10797 @var{urls} is the space-separated list of substitute server URLs to
10798 query. When this option is omitted, the default set of substitute
10799 servers is queried.
10801 @item --system=@var{system}
10802 @itemx -s @var{system}
10803 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10804 option can be repeated, in which case @command{guix weather} will query
10805 substitutes for several system types.
10807 @item --manifest=@var{file}
10808 Instead of querying substitutes for all the packages, only ask for those
10809 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10810 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10813 @item --coverage[=@var{count}]
10814 @itemx -c [@var{count}]
10815 Report on substitute coverage for packages: list packages with at least
10816 @var{count} dependents (zero by default) for which substitutes are
10817 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10818 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10819 @var{b} usually lacks substitutes as well. The result looks like this:
10822 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10823 computing 8,983 package derivations for x86_64-linux...
10824 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10825 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10826 @value{SUBSTITUTE-URL}
10827 64.7% substitutes available (6,047 out of 9,343)
10829 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10830 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10831 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10832 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10836 What this example shows is that @code{kcoreaddons} and presumably the 58
10837 packages that depend on it have no substitutes at @code{ci.guix.info};
10838 likewise for @code{qgpgme} and the 46 packages that depend on it.
10840 If you are a Guix developer, or if you are taking care of this build farm,
10841 you'll probably want to have a closer look at these packages: they may simply
10845 @node Invoking guix processes
10846 @section Invoking @command{guix processes}
10848 The @command{guix processes} command can be useful to developers and system
10849 administrators, especially on multi-user machines and on build farms: it lists
10850 the current sessions (connections to the daemon), as well as information about
10851 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10852 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10853 listed.}. Here's an example of the information it returns:
10856 $ sudo guix processes
10859 ClientCommand: guix environment --ad-hoc python
10863 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10867 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10868 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10869 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10870 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10871 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10872 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10873 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10876 In this example we see that @command{guix-daemon} has three clients:
10877 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10878 integration tool; their process identifier (PID) is given by the
10879 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10880 @command{guix-daemon} sub-process of this particular session.
10882 The @code{LockHeld} fields show which store items are currently locked by this
10883 session, which corresponds to store items being built or substituted (the
10884 @code{LockHeld} field is not displayed when @command{guix processes} is not
10885 running as root.) Last, by looking at the @code{ChildProcess} field, we
10886 understand that these three builds are being offloaded (@pxref{Daemon Offload
10889 The output is in Recutils format so we can use the handy @command{recsel}
10890 command to select sessions of interest (@pxref{Selection Expressions,,,
10891 recutils, GNU recutils manual}). As an example, the command shows the command
10892 line and PID of the client that triggered the build of a Perl package:
10895 $ sudo guix processes | \
10896 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10898 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10901 @node System Configuration
10902 @chapter System Configuration
10904 @cindex system configuration
10905 Guix System supports a consistent whole-system configuration
10906 mechanism. By that we mean that all aspects of the global system
10907 configuration---such as the available system services, timezone and
10908 locale settings, user accounts---are declared in a single place. Such
10909 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10911 One of the advantages of putting all the system configuration under the
10912 control of Guix is that it supports transactional system upgrades, and
10913 makes it possible to roll back to a previous system instantiation,
10914 should something go wrong with the new one (@pxref{Features}). Another
10915 advantage is that it makes it easy to replicate the exact same configuration
10916 across different machines, or at different points in time, without
10917 having to resort to additional administration tools layered on top of
10918 the own tools of the system.
10919 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10921 This section describes this mechanism. First we focus on the system
10922 administrator's viewpoint---explaining how the system is configured and
10923 instantiated. Then we show how this mechanism can be extended, for
10924 instance to support new system services.
10927 * Using the Configuration System:: Customizing your GNU system.
10928 * operating-system Reference:: Detail of operating-system declarations.
10929 * File Systems:: Configuring file system mounts.
10930 * Mapped Devices:: Block device extra processing.
10931 * User Accounts:: Specifying user accounts.
10932 * Keyboard Layout:: How the system interprets key strokes.
10933 * Locales:: Language and cultural convention settings.
10934 * Services:: Specifying system services.
10935 * Setuid Programs:: Programs running with root privileges.
10936 * X.509 Certificates:: Authenticating HTTPS servers.
10937 * Name Service Switch:: Configuring libc's name service switch.
10938 * Initial RAM Disk:: Linux-Libre bootstrapping.
10939 * Bootloader Configuration:: Configuring the boot loader.
10940 * Invoking guix system:: Instantiating a system configuration.
10941 * Invoking guix deploy:: Deploying a system configuration to a remote host.
10942 * Running Guix in a VM:: How to run Guix System in a virtual machine.
10943 * Defining Services:: Adding new service definitions.
10946 @node Using the Configuration System
10947 @section Using the Configuration System
10949 The operating system is configured by providing an
10950 @code{operating-system} declaration in a file that can then be passed to
10951 the @command{guix system} command (@pxref{Invoking guix system}). A
10952 simple setup, with the default system services, the default Linux-Libre
10953 kernel, initial RAM disk, and boot loader looks like this:
10955 @findex operating-system
10957 @include os-config-bare-bones.texi
10960 This example should be self-describing. Some of the fields defined
10961 above, such as @code{host-name} and @code{bootloader}, are mandatory.
10962 Others, such as @code{packages} and @code{services}, can be omitted, in
10963 which case they get a default value.
10965 Below we discuss the effect of some of the most important fields
10966 (@pxref{operating-system Reference}, for details about all the available
10967 fields), and how to @dfn{instantiate} the operating system using
10968 @command{guix system}.
10970 @unnumberedsubsec Bootloader
10972 @cindex legacy boot, on Intel machines
10973 @cindex BIOS boot, on Intel machines
10976 The @code{bootloader} field describes the method that will be used to boot
10977 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
10978 mode, as in the example above. However, more recent machines rely instead on
10979 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
10980 the @code{bootloader} field should contain something along these lines:
10983 (bootloader-configuration
10984 (bootloader grub-efi-bootloader)
10985 (target "/boot/efi"))
10988 @xref{Bootloader Configuration}, for more information on the available
10989 configuration options.
10991 @unnumberedsubsec Globally-Visible Packages
10993 @vindex %base-packages
10994 The @code{packages} field lists packages that will be globally visible
10995 on the system, for all user accounts---i.e., in every user's @code{PATH}
10996 environment variable---in addition to the per-user profiles
10997 (@pxref{Invoking guix package}). The @code{%base-packages} variable
10998 provides all the tools one would expect for basic user and administrator
10999 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
11000 the GNU Zile lightweight text editor, @command{find}, @command{grep},
11001 etc. The example above adds GNU@tie{}Screen to those,
11002 taken from the @code{(gnu packages screen)}
11003 module (@pxref{Package Modules}). The
11004 @code{(list package output)} syntax can be used to add a specific output
11008 (use-modules (gnu packages))
11009 (use-modules (gnu packages dns))
11013 (packages (cons (list bind "utils")
11017 @findex specification->package
11018 Referring to packages by variable name, like @code{bind} above, has
11019 the advantage of being unambiguous; it also allows typos and such to be
11020 diagnosed right away as ``unbound variables''. The downside is that one
11021 needs to know which module defines which package, and to augment the
11022 @code{use-package-modules} line accordingly. To avoid that, one can use
11023 the @code{specification->package} procedure of the @code{(gnu packages)}
11024 module, which returns the best package for a given name or name and
11028 (use-modules (gnu packages))
11032 (packages (append (map specification->package
11033 '("tcpdump" "htop" "gnupg@@2.0"))
11037 @unnumberedsubsec System Services
11040 @vindex %base-services
11041 The @code{services} field lists @dfn{system services} to be made
11042 available when the system starts (@pxref{Services}).
11043 The @code{operating-system} declaration above specifies that, in
11044 addition to the basic services, we want the OpenSSH secure shell
11045 daemon listening on port 2222 (@pxref{Networking Services,
11046 @code{openssh-service-type}}). Under the hood,
11047 @code{openssh-service-type} arranges so that @command{sshd} is started with the
11048 right command-line options, possibly with supporting configuration files
11049 generated as needed (@pxref{Defining Services}).
11051 @cindex customization, of services
11052 @findex modify-services
11053 Occasionally, instead of using the base services as is, you will want to
11054 customize them. To do this, use @code{modify-services} (@pxref{Service
11055 Reference, @code{modify-services}}) to modify the list.
11057 For example, suppose you want to modify @code{guix-daemon} and Mingetty
11058 (the console log-in) in the @code{%base-services} list (@pxref{Base
11059 Services, @code{%base-services}}). To do that, you can write the
11060 following in your operating system declaration:
11063 (define %my-services
11064 ;; My very own list of services.
11065 (modify-services %base-services
11066 (guix-service-type config =>
11067 (guix-configuration
11069 (use-substitutes? #f)
11070 (extra-options '("--gc-keep-derivations"))))
11071 (mingetty-service-type config =>
11072 (mingetty-configuration
11073 (inherit config)))))
11077 (services %my-services))
11080 This changes the configuration---i.e., the service parameters---of the
11081 @code{guix-service-type} instance, and that of all the
11082 @code{mingetty-service-type} instances in the @code{%base-services} list.
11083 Observe how this is accomplished: first, we arrange for the original
11084 configuration to be bound to the identifier @code{config} in the
11085 @var{body}, and then we write the @var{body} so that it evaluates to the
11086 desired configuration. In particular, notice how we use @code{inherit}
11087 to create a new configuration which has the same values as the old
11088 configuration, but with a few modifications.
11090 @cindex encrypted disk
11091 The configuration for a typical ``desktop'' usage, with an encrypted
11092 root partition, the X11 display
11093 server, GNOME and Xfce (users can choose which of these desktop
11094 environments to use at the log-in screen by pressing @kbd{F1}), network
11095 management, power management, and more, would look like this:
11098 @include os-config-desktop.texi
11101 A graphical system with a choice of lightweight window managers
11102 instead of full-blown desktop environments would look like this:
11105 @include os-config-lightweight-desktop.texi
11108 This example refers to the @file{/boot/efi} file system by its UUID,
11109 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
11110 as returned by the @command{blkid} command.
11112 @xref{Desktop Services}, for the exact list of services provided by
11113 @code{%desktop-services}. @xref{X.509 Certificates}, for background
11114 information about the @code{nss-certs} package that is used here.
11116 Again, @code{%desktop-services} is just a list of service objects. If
11117 you want to remove services from there, you can do so using the
11118 procedures for list filtering (@pxref{SRFI-1 Filtering and
11119 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
11120 following expression returns a list that contains all the services in
11121 @code{%desktop-services} minus the Avahi service:
11124 (remove (lambda (service)
11125 (eq? (service-kind service) avahi-service-type))
11129 @unnumberedsubsec Instantiating the System
11131 Assuming the @code{operating-system} declaration
11132 is stored in the @file{my-system-config.scm}
11133 file, the @command{guix system reconfigure my-system-config.scm} command
11134 instantiates that configuration, and makes it the default GRUB boot
11135 entry (@pxref{Invoking guix system}).
11137 The normal way to change the system configuration is by updating this
11138 file and re-running @command{guix system reconfigure}. One should never
11139 have to touch files in @file{/etc} or to run commands that modify the
11140 system state such as @command{useradd} or @command{grub-install}. In
11141 fact, you must avoid that since that would not only void your warranty
11142 but also prevent you from rolling back to previous versions of your
11143 system, should you ever need to.
11145 @cindex roll-back, of the operating system
11146 Speaking of roll-back, each time you run @command{guix system
11147 reconfigure}, a new @dfn{generation} of the system is created---without
11148 modifying or deleting previous generations. Old system generations get
11149 an entry in the bootloader boot menu, allowing you to boot them in case
11150 something went wrong with the latest generation. Reassuring, no? The
11151 @command{guix system list-generations} command lists the system
11152 generations available on disk. It is also possible to roll back the
11153 system via the commands @command{guix system roll-back} and
11154 @command{guix system switch-generation}.
11156 Although the @command{guix system reconfigure} command will not modify
11157 previous generations, you must take care when the current generation is not
11158 the latest (e.g., after invoking @command{guix system roll-back}), since
11159 the operation might overwrite a later generation (@pxref{Invoking guix
11162 @unnumberedsubsec The Programming Interface
11164 At the Scheme level, the bulk of an @code{operating-system} declaration
11165 is instantiated with the following monadic procedure (@pxref{The Store
11168 @deffn {Monadic Procedure} operating-system-derivation os
11169 Return a derivation that builds @var{os}, an @code{operating-system}
11170 object (@pxref{Derivations}).
11172 The output of the derivation is a single directory that refers to all
11173 the packages, configuration files, and other supporting files needed to
11174 instantiate @var{os}.
11177 This procedure is provided by the @code{(gnu system)} module. Along
11178 with @code{(gnu services)} (@pxref{Services}), this module contains the
11179 guts of Guix System. Make sure to visit it!
11182 @node operating-system Reference
11183 @section @code{operating-system} Reference
11185 This section summarizes all the options available in
11186 @code{operating-system} declarations (@pxref{Using the Configuration
11189 @deftp {Data Type} operating-system
11190 This is the data type representing an operating system configuration.
11191 By that, we mean all the global system configuration, not per-user
11192 configuration (@pxref{Using the Configuration System}).
11195 @item @code{kernel} (default: @var{linux-libre})
11196 The package object of the operating system kernel to use@footnote{Currently
11197 only the Linux-libre kernel is supported. In the future, it will be
11198 possible to use the GNU@tie{}Hurd.}.
11200 @item @code{kernel-arguments} (default: @code{'("quiet")})
11201 List of strings or gexps representing additional arguments to pass on
11202 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
11204 @item @code{bootloader}
11205 The system bootloader configuration object. @xref{Bootloader Configuration}.
11208 This is the label (a string) as it appears in the bootloader's menu entry.
11209 The default label includes the kernel name and version.
11211 @item @code{keyboard-layout} (default: @code{#f})
11212 This field specifies the keyboard layout to use in the console. It can be
11213 either @code{#f}, in which case the default keyboard layout is used (usually
11214 US English), or a @code{<keyboard-layout>} record.
11216 This keyboard layout is in effect as soon as the kernel has booted. For
11217 instance, it is the keyboard layout in effect when you type a passphrase if
11218 your root file system is on a @code{luks-device-mapping} mapped device
11219 (@pxref{Mapped Devices}).
11222 This does @emph{not} specify the keyboard layout used by the bootloader, nor
11223 that used by the graphical display server. @xref{Bootloader Configuration},
11224 for information on how to specify the bootloader's keyboard layout. @xref{X
11225 Window}, for information on how to specify the keyboard layout used by the X
11229 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
11231 @cindex initial RAM disk
11232 The list of Linux kernel modules that need to be available in the
11233 initial RAM disk. @xref{Initial RAM Disk}.
11235 @item @code{initrd} (default: @code{base-initrd})
11236 A procedure that returns an initial RAM disk for the Linux
11237 kernel. This field is provided to support low-level customization and
11238 should rarely be needed for casual use. @xref{Initial RAM Disk}.
11240 @item @code{firmware} (default: @code{%base-firmware})
11242 List of firmware packages loadable by the operating system kernel.
11244 The default includes firmware needed for Atheros- and Broadcom-based
11245 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
11246 respectively). @xref{Hardware Considerations}, for more info on
11247 supported hardware.
11249 @item @code{host-name}
11252 @item @code{hosts-file}
11254 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
11255 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
11256 Reference Manual}). The default is a file with entries for
11257 @code{localhost} and @var{host-name}.
11259 @item @code{mapped-devices} (default: @code{'()})
11260 A list of mapped devices. @xref{Mapped Devices}.
11262 @item @code{file-systems}
11263 A list of file systems. @xref{File Systems}.
11265 @item @code{swap-devices} (default: @code{'()})
11266 @cindex swap devices
11267 A list of strings identifying devices or files to be used for ``swap
11268 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
11269 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
11270 It is possible to specify a swap file in a file system on a mapped
11271 device, provided that the necessary device mapping and file system are
11272 also specified. @xref{Mapped Devices} and @ref{File Systems}.
11274 @item @code{users} (default: @code{%base-user-accounts})
11275 @itemx @code{groups} (default: @code{%base-groups})
11276 List of user accounts and groups. @xref{User Accounts}.
11278 If the @code{users} list lacks a user account with UID@tie{}0, a
11279 ``root'' account with UID@tie{}0 is automatically added.
11281 @item @code{skeletons} (default: @code{(default-skeletons)})
11282 A list target file name/file-like object tuples (@pxref{G-Expressions,
11283 file-like objects}). These are the skeleton files that will be added to
11284 the home directory of newly-created user accounts.
11286 For instance, a valid value may look like this:
11289 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
11290 (".guile" ,(plain-file "guile"
11291 "(use-modules (ice-9 readline))
11292 (activate-readline)")))
11295 @item @code{issue} (default: @code{%default-issue})
11296 A string denoting the contents of the @file{/etc/issue} file, which is
11297 displayed when users log in on a text console.
11299 @item @code{packages} (default: @code{%base-packages})
11300 The set of packages installed in the global profile, which is accessible
11301 at @file{/run/current-system/profile}.
11303 The default set includes core utilities and it is good practice to
11304 install non-core utilities in user profiles (@pxref{Invoking guix
11307 @item @code{timezone}
11308 A timezone identifying string---e.g., @code{"Europe/Paris"}.
11310 You can run the @command{tzselect} command to find out which timezone
11311 string corresponds to your region. Choosing an invalid timezone name
11312 causes @command{guix system} to fail.
11314 @item @code{locale} (default: @code{"en_US.utf8"})
11315 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
11316 Library Reference Manual}). @xref{Locales}, for more information.
11318 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
11319 The list of locale definitions to be compiled and that may be used at
11320 run time. @xref{Locales}.
11322 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
11323 The list of GNU@tie{}libc packages whose locale data and tools are used
11324 to build the locale definitions. @xref{Locales}, for compatibility
11325 considerations that justify this option.
11327 @item @code{name-service-switch} (default: @code{%default-nss})
11328 Configuration of the libc name service switch (NSS)---a
11329 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
11332 @item @code{services} (default: @code{%base-services})
11333 A list of service objects denoting system services. @xref{Services}.
11335 @cindex essential services
11336 @item @code{essential-services} (default: ...)
11337 The list of ``essential services''---i.e., things like instances of
11338 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
11339 Reference}), which are derived from the operating system definition itself.
11340 As a user you should @emph{never} need to touch this field.
11342 @item @code{pam-services} (default: @code{(base-pam-services)})
11344 @cindex pluggable authentication modules
11345 Linux @dfn{pluggable authentication module} (PAM) services.
11346 @c FIXME: Add xref to PAM services section.
11348 @item @code{setuid-programs} (default: @var{%setuid-programs})
11349 List of string-valued G-expressions denoting setuid programs.
11350 @xref{Setuid Programs}.
11352 @item @code{sudoers-file} (default: @var{%sudoers-specification})
11353 @cindex sudoers file
11354 The contents of the @file{/etc/sudoers} file as a file-like object
11355 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
11357 This file specifies which users can use the @command{sudo} command, what
11358 they are allowed to do, and what privileges they may gain. The default
11359 is that only @code{root} and members of the @code{wheel} group may use
11364 @deffn {Scheme Syntax} this-operating-system
11365 When used in the @emph{lexical scope} of an operating system field definition,
11366 this identifier resolves to the operating system being defined.
11368 The example below shows how to refer to the operating system being defined in
11369 the definition of the @code{label} field:
11372 (use-modules (gnu) (guix))
11376 (label (package-full-name
11377 (operating-system-kernel this-operating-system))))
11380 It is an error to refer to @code{this-operating-system} outside an operating
11387 @section File Systems
11389 The list of file systems to be mounted is specified in the
11390 @code{file-systems} field of the operating system declaration
11391 (@pxref{Using the Configuration System}). Each file system is declared
11392 using the @code{file-system} form, like this:
11396 (mount-point "/home")
11397 (device "/dev/sda3")
11401 As usual, some of the fields are mandatory---those shown in the example
11402 above---while others can be omitted. These are described below.
11404 @deftp {Data Type} file-system
11405 Objects of this type represent file systems to be mounted. They
11406 contain the following members:
11410 This is a string specifying the type of the file system---e.g.,
11413 @item @code{mount-point}
11414 This designates the place where the file system is to be mounted.
11416 @item @code{device}
11417 This names the ``source'' of the file system. It can be one of three
11418 things: a file system label, a file system UUID, or the name of a
11419 @file{/dev} node. Labels and UUIDs offer a way to refer to file
11420 systems without having to hard-code their actual device
11421 name@footnote{Note that, while it is tempting to use
11422 @file{/dev/disk/by-uuid} and similar device names to achieve the same
11423 result, this is not recommended: These special device nodes are created
11424 by the udev daemon and may be unavailable at the time the device is
11427 @findex file-system-label
11428 File system labels are created using the @code{file-system-label}
11429 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
11430 plain strings. Here's an example of a file system referred to by its
11431 label, as shown by the @command{e2label} command:
11435 (mount-point "/home")
11437 (device (file-system-label "my-home")))
11441 UUIDs are converted from their string representation (as shown by the
11442 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
11443 @code{uuid} form expects 16-byte UUIDs as defined in
11444 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
11445 form of UUID used by the ext2 family of file systems and others, but it
11446 is different from ``UUIDs'' found in FAT file systems, for instance.},
11451 (mount-point "/home")
11453 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
11456 When the source of a file system is a mapped device (@pxref{Mapped
11457 Devices}), its @code{device} field @emph{must} refer to the mapped
11458 device name---e.g., @file{"/dev/mapper/root-partition"}.
11459 This is required so that
11460 the system knows that mounting the file system depends on having the
11461 corresponding device mapping established.
11463 @item @code{flags} (default: @code{'()})
11464 This is a list of symbols denoting mount flags. Recognized flags
11465 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
11466 access to special files), @code{no-suid} (ignore setuid and setgid
11467 bits), @code{no-atime} (do not update file access times),
11468 @code{strict-atime} (update file access time), @code{lazy-time} (only
11469 update time on the in-memory version of the file inode), and
11470 @code{no-exec} (disallow program execution).
11471 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
11472 Manual}, for more information on these flags.
11474 @item @code{options} (default: @code{#f})
11475 This is either @code{#f}, or a string denoting mount options passed to the
11476 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
11477 Reference Manual}, for details and run @command{man 8 mount} for options for
11478 various file systems.
11480 @item @code{mount?} (default: @code{#t})
11481 This value indicates whether to automatically mount the file system when
11482 the system is brought up. When set to @code{#f}, the file system gets
11483 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
11484 is not automatically mounted.
11486 @item @code{needed-for-boot?} (default: @code{#f})
11487 This Boolean value indicates whether the file system is needed when
11488 booting. If that is true, then the file system is mounted when the
11489 initial RAM disk (initrd) is loaded. This is always the case, for
11490 instance, for the root file system.
11492 @item @code{check?} (default: @code{#t})
11493 This Boolean indicates whether the file system needs to be checked for
11494 errors before being mounted.
11496 @item @code{create-mount-point?} (default: @code{#f})
11497 When true, the mount point is created if it does not exist yet.
11499 @item @code{dependencies} (default: @code{'()})
11500 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
11501 representing file systems that must be mounted or mapped devices that
11502 must be opened before (and unmounted or closed after) this one.
11504 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
11505 a dependency of @file{/sys/fs/cgroup/cpu} and
11506 @file{/sys/fs/cgroup/memory}.
11508 Another example is a file system that depends on a mapped device, for
11509 example for an encrypted partition (@pxref{Mapped Devices}).
11513 The @code{(gnu system file-systems)} exports the following useful
11516 @defvr {Scheme Variable} %base-file-systems
11517 These are essential file systems that are required on normal systems,
11518 such as @var{%pseudo-terminal-file-system} and @var{%immutable-store} (see
11519 below.) Operating system declarations should always contain at least
11523 @defvr {Scheme Variable} %pseudo-terminal-file-system
11524 This is the file system to be mounted as @file{/dev/pts}. It supports
11525 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
11526 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
11527 Manual}). Pseudo-terminals are used by terminal emulators such as
11531 @defvr {Scheme Variable} %shared-memory-file-system
11532 This file system is mounted as @file{/dev/shm} and is used to support
11533 memory sharing across processes (@pxref{Memory-mapped I/O,
11534 @code{shm_open},, libc, The GNU C Library Reference Manual}).
11537 @defvr {Scheme Variable} %immutable-store
11538 This file system performs a read-only ``bind mount'' of
11539 @file{/gnu/store}, making it read-only for all the users including
11540 @code{root}. This prevents against accidental modification by software
11541 running as @code{root} or by system administrators.
11543 The daemon itself is still able to write to the store: it remounts it
11544 read-write in its own ``name space.''
11547 @defvr {Scheme Variable} %binary-format-file-system
11548 The @code{binfmt_misc} file system, which allows handling of arbitrary
11549 executable file types to be delegated to user space. This requires the
11550 @code{binfmt.ko} kernel module to be loaded.
11553 @defvr {Scheme Variable} %fuse-control-file-system
11554 The @code{fusectl} file system, which allows unprivileged users to mount
11555 and unmount user-space FUSE file systems. This requires the
11556 @code{fuse.ko} kernel module to be loaded.
11559 @node Mapped Devices
11560 @section Mapped Devices
11562 @cindex device mapping
11563 @cindex mapped devices
11564 The Linux kernel has a notion of @dfn{device mapping}: a block device,
11565 such as a hard disk partition, can be @dfn{mapped} into another device,
11566 usually in @code{/dev/mapper/},
11567 with additional processing over the data that flows through
11568 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
11569 concept of a ``mapped device'' and that of a file system: both boil down
11570 to @emph{translating} input/output operations made on a file to
11571 operations on its backing store. Thus, the Hurd implements mapped
11572 devices, like file systems, using the generic @dfn{translator} mechanism
11573 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
11574 typical example is encryption device mapping: all writes to the mapped
11575 device are encrypted, and all reads are deciphered, transparently.
11576 Guix extends this notion by considering any device or set of devices that
11577 are @dfn{transformed} in some way to create a new device; for instance,
11578 RAID devices are obtained by @dfn{assembling} several other devices, such
11579 as hard disks or partitions, into a new one that behaves as one partition.
11580 Other examples, not yet implemented, are LVM logical volumes.
11582 Mapped devices are declared using the @code{mapped-device} form,
11583 defined as follows; for examples, see below.
11585 @deftp {Data Type} mapped-device
11586 Objects of this type represent device mappings that will be made when
11587 the system boots up.
11591 This is either a string specifying the name of the block device to be mapped,
11592 such as @code{"/dev/sda3"}, or a list of such strings when several devices
11593 need to be assembled for creating a new one.
11596 This string specifies the name of the resulting mapped device. For
11597 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
11598 specifying @code{"my-partition"} leads to the creation of
11599 the @code{"/dev/mapper/my-partition"} device.
11600 For RAID devices of type @code{raid-device-mapping}, the full device name
11601 such as @code{"/dev/md0"} needs to be given.
11604 This must be a @code{mapped-device-kind} object, which specifies how
11605 @var{source} is mapped to @var{target}.
11609 @defvr {Scheme Variable} luks-device-mapping
11610 This defines LUKS block device encryption using the @command{cryptsetup}
11611 command from the package with the same name. It relies on the
11612 @code{dm-crypt} Linux kernel module.
11615 @defvr {Scheme Variable} raid-device-mapping
11616 This defines a RAID device, which is assembled using the @code{mdadm}
11617 command from the package with the same name. It requires a Linux kernel
11618 module for the appropriate RAID level to be loaded, such as @code{raid456}
11619 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
11622 @cindex disk encryption
11624 The following example specifies a mapping from @file{/dev/sda3} to
11625 @file{/dev/mapper/home} using LUKS---the
11626 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
11627 standard mechanism for disk encryption.
11628 The @file{/dev/mapper/home}
11629 device can then be used as the @code{device} of a @code{file-system}
11630 declaration (@pxref{File Systems}).
11634 (source "/dev/sda3")
11636 (type luks-device-mapping))
11639 Alternatively, to become independent of device numbering, one may obtain
11640 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11644 cryptsetup luksUUID /dev/sda3
11647 and use it as follows:
11651 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11653 (type luks-device-mapping))
11656 @cindex swap encryption
11657 It is also desirable to encrypt swap space, since swap space may contain
11658 sensitive data. One way to accomplish that is to use a swap file in a
11659 file system on a device mapped via LUKS encryption. In this way, the
11660 swap file is encrypted because the entire device is encrypted.
11661 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11663 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11664 may be declared as follows:
11668 (source (list "/dev/sda1" "/dev/sdb1"))
11669 (target "/dev/md0")
11670 (type raid-device-mapping))
11673 The @file{/dev/md0} device can then be used as the @code{device} of a
11674 @code{file-system} declaration (@pxref{File Systems}).
11675 Note that the RAID level need not be given; it is chosen during the
11676 initial creation and formatting of the RAID device and is determined
11677 automatically later.
11680 @node User Accounts
11681 @section User Accounts
11685 @cindex user accounts
11686 User accounts and groups are entirely managed through the
11687 @code{operating-system} declaration. They are specified with the
11688 @code{user-account} and @code{user-group} forms:
11694 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11695 "audio" ;sound card
11696 "video" ;video devices such as webcams
11697 "cdrom")) ;the good ol' CD-ROM
11698 (comment "Bob's sister")
11699 (home-directory "/home/alice"))
11702 When booting or upon completion of @command{guix system reconfigure},
11703 the system ensures that only the user accounts and groups specified in
11704 the @code{operating-system} declaration exist, and with the specified
11705 properties. Thus, account or group creations or modifications made by
11706 directly invoking commands such as @command{useradd} are lost upon
11707 reconfiguration or reboot. This ensures that the system remains exactly
11710 @deftp {Data Type} user-account
11711 Objects of this type represent user accounts. The following members may
11716 The name of the user account.
11720 This is the name (a string) or identifier (a number) of the user group
11721 this account belongs to.
11723 @item @code{supplementary-groups} (default: @code{'()})
11724 Optionally, this can be defined as a list of group names that this
11725 account belongs to.
11727 @item @code{uid} (default: @code{#f})
11728 This is the user ID for this account (a number), or @code{#f}. In the
11729 latter case, a number is automatically chosen by the system when the
11730 account is created.
11732 @item @code{comment} (default: @code{""})
11733 A comment about the account, such as the account owner's full name.
11735 @item @code{home-directory}
11736 This is the name of the home directory for the account.
11738 @item @code{create-home-directory?} (default: @code{#t})
11739 Indicates whether the home directory of this account should be created
11740 if it does not exist yet.
11742 @item @code{shell} (default: Bash)
11743 This is a G-expression denoting the file name of a program to be used as
11744 the shell (@pxref{G-Expressions}).
11746 @item @code{system?} (default: @code{#f})
11747 This Boolean value indicates whether the account is a ``system''
11748 account. System accounts are sometimes treated specially; for instance,
11749 graphical login managers do not list them.
11751 @anchor{user-account-password}
11752 @cindex password, for user accounts
11753 @item @code{password} (default: @code{#f})
11754 You would normally leave this field to @code{#f}, initialize user
11755 passwords as @code{root} with the @command{passwd} command, and then let
11756 users change it with @command{passwd}. Passwords set with
11757 @command{passwd} are of course preserved across reboot and
11760 If you @emph{do} want to set an initial password for an account, then
11761 this field must contain the encrypted password, as a string. You can use the
11762 @code{crypt} procedure for this purpose:
11769 ;; Specify a SHA-512-hashed initial password.
11770 (password (crypt "InitialPassword!" "$6$abc")))
11774 The hash of this initial password will be available in a file in
11775 @file{/gnu/store}, readable by all the users, so this method must be used with
11779 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11780 more information on password encryption, and @ref{Encryption,,, guile, GNU
11781 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11787 User group declarations are even simpler:
11790 (user-group (name "students"))
11793 @deftp {Data Type} user-group
11794 This type is for, well, user groups. There are just a few fields:
11798 The name of the group.
11800 @item @code{id} (default: @code{#f})
11801 The group identifier (a number). If @code{#f}, a new number is
11802 automatically allocated when the group is created.
11804 @item @code{system?} (default: @code{#f})
11805 This Boolean value indicates whether the group is a ``system'' group.
11806 System groups have low numerical IDs.
11808 @item @code{password} (default: @code{#f})
11809 What, user groups can have a password? Well, apparently yes. Unless
11810 @code{#f}, this field specifies the password of the group.
11815 For convenience, a variable lists all the basic user groups one may
11818 @defvr {Scheme Variable} %base-groups
11819 This is the list of basic user groups that users and/or packages expect
11820 to be present on the system. This includes groups such as ``root'',
11821 ``wheel'', and ``users'', as well as groups used to control access to
11822 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11825 @defvr {Scheme Variable} %base-user-accounts
11826 This is the list of basic system accounts that programs may expect to
11827 find on a GNU/Linux system, such as the ``nobody'' account.
11829 Note that the ``root'' account is not included here. It is a
11830 special-case and is automatically added whether or not it is specified.
11833 @node Keyboard Layout
11834 @section Keyboard Layout
11836 @cindex keyboard layout
11838 To specify what each key of your keyboard does, you need to tell the operating
11839 system what @dfn{keyboard layout} you want to use. The default, when nothing
11840 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11841 However, German speakers will usually prefer the German QWERTZ layout, French
11842 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11843 or bépo, and they might even want to further customize the effect of some of
11844 the keys. This section explains how to get that done.
11846 @cindex keyboard layout, definition
11847 There are three components that will want to know about your keyboard layout:
11851 The @emph{bootloader} may want to know what keyboard layout you want to use
11852 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11853 you want, for instance, to make sure that you can type the passphrase of your
11854 encrypted root partition using the right layout.
11857 The @emph{operating system kernel}, Linux, will need that so that the console
11858 is properly configured (@pxref{operating-system Reference,
11859 @code{keyboard-layout}}).
11862 The @emph{graphical display server}, usually Xorg, also has its own idea of
11863 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11866 Guix allows you to configure all three separately but, fortunately, it allows
11867 you to share the same keyboard layout for all three components.
11869 @cindex XKB, keyboard layouts
11870 Keyboard layouts are represented by records created by the
11871 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11872 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11873 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11874 optional variant name, an optional keyboard model name, and a possibly empty
11875 list of additional options. In most cases the layout name is all you care
11876 about. Here are a few example:
11879 ;; The German QWERTZ layout. Here we assume a standard
11880 ;; "pc105" keyboard model.
11881 (keyboard-layout "de")
11883 ;; The bépo variant of the French layout.
11884 (keyboard-layout "fr" "bepo")
11886 ;; The Catalan layout.
11887 (keyboard-layout "es" "cat")
11889 ;; The Latin American Spanish layout. In addition, the
11890 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11891 ;; and the "Menu" key is used as a "Compose" key to enter
11892 ;; accented letters.
11893 (keyboard-layout "latam"
11894 #:options '("ctrl:nocaps" "compose:menu"))
11896 ;; The Russian layout for a ThinkPad keyboard.
11897 (keyboard-layout "ru" #:model "thinkpad")
11899 ;; The "US international" layout, which is the US layout plus
11900 ;; dead keys to enter accented characters. This is for an
11901 ;; Apple MacBook keyboard.
11902 (keyboard-layout "us" "intl" #:model "macbook78")
11905 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11906 for a complete list of supported layouts, variants, and models.
11908 @cindex keyboard layout, configuration
11909 Let's say you want your system to use the Turkish keyboard layout throughout
11910 your system---bootloader, console, and Xorg. Here's what your system
11911 configuration would look like:
11913 @findex set-xorg-configuration
11915 ;; Using the Turkish layout for the bootloader, the console,
11920 (keyboard-layout (keyboard-layout "tr")) ;for the console
11921 (bootloader (bootloader-configuration
11922 (bootloader grub-efi-bootloader)
11923 (target "/boot/efi")
11924 (keyboard-layout keyboard-layout))) ;for GRUB
11925 (services (cons (set-xorg-configuration
11926 (xorg-configuration ;for Xorg
11927 (keyboard-layout keyboard-layout)))
11928 %desktop-services)))
11931 In the example above, for GRUB and for Xorg, we just refer to the
11932 @code{keyboard-layout} field defined above, but we could just as well refer to
11933 a different layout. The @code{set-xorg-configuration} procedure communicates
11934 the desired Xorg configuration to the graphical log-in manager, by default
11937 We've discussed how to specify the @emph{default} keyboard layout of your
11938 system when it starts, but you can also adjust it at run time:
11942 If you're using GNOME, its settings panel has a ``Region & Language'' entry
11943 where you can select one or more keyboard layouts.
11946 Under Xorg, the @command{setxkbmap} command (from the same-named package)
11947 allows you to change the current layout. For example, this is how you would
11948 change the layout to US Dvorak:
11951 setxkbmap us dvorak
11955 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
11956 console. However, note that @code{loadkeys} does @emph{not} use the XKB
11957 keyboard layout categorization described above. The command below loads the
11958 French bépo layout:
11969 A @dfn{locale} defines cultural conventions for a particular language
11970 and region of the world (@pxref{Locales,,, libc, The GNU C Library
11971 Reference Manual}). Each locale has a name that typically has the form
11972 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
11973 @code{fr_LU.utf8} designates the locale for the French language, with
11974 cultural conventions from Luxembourg, and using the UTF-8 encoding.
11976 @cindex locale definition
11977 Usually, you will want to specify the default locale for the machine
11978 using the @code{locale} field of the @code{operating-system} declaration
11979 (@pxref{operating-system Reference, @code{locale}}).
11981 The selected locale is automatically added to the @dfn{locale
11982 definitions} known to the system if needed, with its codeset inferred
11983 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
11984 @code{UTF-8} codeset. Additional locale definitions can be specified in
11985 the @code{locale-definitions} slot of @code{operating-system}---this is
11986 useful, for instance, if the codeset could not be inferred from the
11987 locale name. The default set of locale definitions includes some widely
11988 used locales, but not all the available locales, in order to save space.
11990 For instance, to add the North Frisian locale for Germany, the value of
11994 (cons (locale-definition
11995 (name "fy_DE.utf8") (source "fy_DE"))
11996 %default-locale-definitions)
11999 Likewise, to save space, one might want @code{locale-definitions} to
12000 list only the locales that are actually used, as in:
12003 (list (locale-definition
12004 (name "ja_JP.eucjp") (source "ja_JP")
12005 (charset "EUC-JP")))
12009 The compiled locale definitions are available at
12010 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
12011 version, which is the default location where the GNU@tie{}libc provided
12012 by Guix looks for locale data. This can be overridden using the
12013 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
12014 @code{LOCPATH} and locale packages}).
12016 The @code{locale-definition} form is provided by the @code{(gnu system
12017 locale)} module. Details are given below.
12019 @deftp {Data Type} locale-definition
12020 This is the data type of a locale definition.
12025 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
12026 Reference Manual}, for more information on locale names.
12028 @item @code{source}
12029 The name of the source for that locale. This is typically the
12030 @code{@var{language}_@var{territory}} part of the locale name.
12032 @item @code{charset} (default: @code{"UTF-8"})
12033 The ``character set'' or ``code set'' for that locale,
12034 @uref{https://www.iana.org/assignments/character-sets, as defined by
12040 @defvr {Scheme Variable} %default-locale-definitions
12041 A list of commonly used UTF-8 locales, used as the default
12042 value of the @code{locale-definitions} field of @code{operating-system}
12045 @cindex locale name
12046 @cindex normalized codeset in locale names
12047 These locale definitions use the @dfn{normalized codeset} for the part
12048 that follows the dot in the name (@pxref{Using gettextized software,
12049 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
12050 instance it has @code{uk_UA.utf8} but @emph{not}, say,
12051 @code{uk_UA.UTF-8}.
12054 @subsection Locale Data Compatibility Considerations
12056 @cindex incompatibility, of locale data
12057 @code{operating-system} declarations provide a @code{locale-libcs} field
12058 to specify the GNU@tie{}libc packages that are used to compile locale
12059 declarations (@pxref{operating-system Reference}). ``Why would I
12060 care?'', you may ask. Well, it turns out that the binary format of
12061 locale data is occasionally incompatible from one libc version to
12064 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
12065 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
12066 For instance, a program linked against libc version 2.21 is unable to
12067 read locale data produced with libc 2.22; worse, that program
12068 @emph{aborts} instead of simply ignoring the incompatible locale
12069 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
12070 the incompatible locale data, which is already an improvement.}.
12071 Similarly, a program linked against libc 2.22 can read most, but not
12072 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
12073 data is incompatible); thus calls to @code{setlocale} may fail, but
12074 programs will not abort.
12076 The ``problem'' with Guix is that users have a lot of freedom: They can
12077 choose whether and when to upgrade software in their profiles, and might
12078 be using a libc version different from the one the system administrator
12079 used to build the system-wide locale data.
12081 Fortunately, unprivileged users can also install their own locale data
12082 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
12083 @code{GUIX_LOCPATH} and locale packages}).
12085 Still, it is best if the system-wide locale data at
12086 @file{/run/current-system/locale} is built for all the libc versions
12087 actually in use on the system, so that all the programs can access
12088 it---this is especially crucial on a multi-user system. To do that, the
12089 administrator can specify several libc packages in the
12090 @code{locale-libcs} field of @code{operating-system}:
12093 (use-package-modules base)
12097 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
12100 This example would lead to a system containing locale definitions for
12101 both libc 2.21 and the current version of libc in
12102 @file{/run/current-system/locale}.
12108 @cindex system services
12109 An important part of preparing an @code{operating-system} declaration is
12110 listing @dfn{system services} and their configuration (@pxref{Using the
12111 Configuration System}). System services are typically daemons launched
12112 when the system boots, or other actions needed at that time---e.g.,
12113 configuring network access.
12115 Guix has a broad definition of ``service'' (@pxref{Service
12116 Composition}), but many services are managed by the GNU@tie{}Shepherd
12117 (@pxref{Shepherd Services}). On a running system, the @command{herd}
12118 command allows you to list the available services, show their status,
12119 start and stop them, or do other specific operations (@pxref{Jump
12120 Start,,, shepherd, The GNU Shepherd Manual}). For example:
12126 The above command, run as @code{root}, lists the currently defined
12127 services. The @command{herd doc} command shows a synopsis of the given
12128 service and its associated actions:
12132 Run libc's name service cache daemon (nscd).
12134 # herd doc nscd action invalidate
12135 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
12138 The @command{start}, @command{stop}, and @command{restart} sub-commands
12139 have the effect you would expect. For instance, the commands below stop
12140 the nscd service and restart the Xorg display server:
12144 Service nscd has been stopped.
12145 # herd restart xorg-server
12146 Service xorg-server has been stopped.
12147 Service xorg-server has been started.
12150 The following sections document the available services, starting with
12151 the core services, that may be used in an @code{operating-system}
12155 * Base Services:: Essential system services.
12156 * Scheduled Job Execution:: The mcron service.
12157 * Log Rotation:: The rottlog service.
12158 * Networking Services:: Network setup, SSH daemon, etc.
12159 * X Window:: Graphical display.
12160 * Printing Services:: Local and remote printer support.
12161 * Desktop Services:: D-Bus and desktop services.
12162 * Sound Services:: ALSA and Pulseaudio services.
12163 * Database Services:: SQL databases, key-value stores, etc.
12164 * Mail Services:: IMAP, POP3, SMTP, and all that.
12165 * Messaging Services:: Messaging services.
12166 * Telephony Services:: Telephony services.
12167 * Monitoring Services:: Monitoring services.
12168 * Kerberos Services:: Kerberos services.
12169 * LDAP Services:: LDAP services.
12170 * Web Services:: Web servers.
12171 * Certificate Services:: TLS certificates via Let's Encrypt.
12172 * DNS Services:: DNS daemons.
12173 * VPN Services:: VPN daemons.
12174 * Network File System:: NFS related services.
12175 * Continuous Integration:: The Cuirass service.
12176 * Power Management Services:: Extending battery life.
12177 * Audio Services:: The MPD.
12178 * Virtualization Services:: Virtualization services.
12179 * Version Control Services:: Providing remote access to Git repositories.
12180 * Game Services:: Game servers.
12181 * PAM Mount Service:: Service to mount volumes when logging in.
12182 * Guix Services:: Services relating specifically to Guix.
12183 * Linux Services:: Services tied to the Linux kernel.
12184 * Miscellaneous Services:: Other services.
12187 @node Base Services
12188 @subsection Base Services
12190 The @code{(gnu services base)} module provides definitions for the basic
12191 services that one expects from the system. The services exported by
12192 this module are listed below.
12194 @defvr {Scheme Variable} %base-services
12195 This variable contains a list of basic services (@pxref{Service Types
12196 and Services}, for more information on service objects) one would
12197 expect from the system: a login service (mingetty) on each tty, syslogd,
12198 the libc name service cache daemon (nscd), the udev device manager, and
12201 This is the default value of the @code{services} field of
12202 @code{operating-system} declarations. Usually, when customizing a
12203 system, you will want to append services to @code{%base-services}, like
12207 (append (list (service avahi-service-type)
12208 (service openssh-service-type))
12213 @defvr {Scheme Variable} special-files-service-type
12214 This is the service that sets up ``special files'' such as
12215 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
12217 The value associated with @code{special-files-service-type} services
12218 must be a list of tuples where the first element is the ``special file''
12219 and the second element is its target. By default it is:
12221 @cindex @file{/bin/sh}
12222 @cindex @file{sh}, in @file{/bin}
12224 `(("/bin/sh" ,(file-append bash "/bin/sh")))
12227 @cindex @file{/usr/bin/env}
12228 @cindex @file{env}, in @file{/usr/bin}
12229 If you want to add, say, @code{/usr/bin/env} to your system, you can
12233 `(("/bin/sh" ,(file-append bash "/bin/sh"))
12234 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
12237 Since this is part of @code{%base-services}, you can use
12238 @code{modify-services} to customize the set of special files
12239 (@pxref{Service Reference, @code{modify-services}}). But the simple way
12240 to add a special file is @i{via} the @code{extra-special-file} procedure
12244 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
12245 Use @var{target} as the ``special file'' @var{file}.
12247 For example, adding the following lines to the @code{services} field of
12248 your operating system declaration leads to a @file{/usr/bin/env}
12252 (extra-special-file "/usr/bin/env"
12253 (file-append coreutils "/bin/env"))
12257 @deffn {Scheme Procedure} host-name-service @var{name}
12258 Return a service that sets the host name to @var{name}.
12261 @deffn {Scheme Procedure} login-service @var{config}
12262 Return a service to run login according to @var{config}, a
12263 @code{<login-configuration>} object, which specifies the message of the day,
12264 among other things.
12267 @deftp {Data Type} login-configuration
12268 This is the data type representing the configuration of login.
12273 @cindex message of the day
12274 A file-like object containing the ``message of the day''.
12276 @item @code{allow-empty-passwords?} (default: @code{#t})
12277 Allow empty passwords by default so that first-time users can log in when
12278 the 'root' account has just been created.
12283 @deffn {Scheme Procedure} mingetty-service @var{config}
12284 Return a service to run mingetty according to @var{config}, a
12285 @code{<mingetty-configuration>} object, which specifies the tty to run, among
12289 @deftp {Data Type} mingetty-configuration
12290 This is the data type representing the configuration of Mingetty, which
12291 provides the default implementation of virtual console log-in.
12296 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
12298 @item @code{auto-login} (default: @code{#f})
12299 When true, this field must be a string denoting the user name under
12300 which the system automatically logs in. When it is @code{#f}, a
12301 user name and password must be entered to log in.
12303 @item @code{login-program} (default: @code{#f})
12304 This must be either @code{#f}, in which case the default log-in program
12305 is used (@command{login} from the Shadow tool suite), or a gexp denoting
12306 the name of the log-in program.
12308 @item @code{login-pause?} (default: @code{#f})
12309 When set to @code{#t} in conjunction with @var{auto-login}, the user
12310 will have to press a key before the log-in shell is launched.
12312 @item @code{mingetty} (default: @var{mingetty})
12313 The Mingetty package to use.
12318 @deffn {Scheme Procedure} agetty-service @var{config}
12319 Return a service to run agetty according to @var{config}, an
12320 @code{<agetty-configuration>} object, which specifies the tty to run,
12321 among other things.
12324 @deftp {Data Type} agetty-configuration
12325 This is the data type representing the configuration of agetty, which
12326 implements virtual and serial console log-in. See the @code{agetty(8)}
12327 man page for more information.
12332 The name of the console this agetty runs on, as a string---e.g.,
12333 @code{"ttyS0"}. This argument is optional, it will default to
12334 a reasonable default serial port used by the kernel Linux.
12336 For this, if there is a value for an option @code{agetty.tty} in the kernel
12337 command line, agetty will extract the device name of the serial port
12338 from it and use that.
12340 If not and if there is a value for an option @code{console} with a tty in
12341 the Linux command line, agetty will extract the device name of the
12342 serial port from it and use that.
12344 In both cases, agetty will leave the other serial device settings
12345 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
12348 @item @code{baud-rate} (default: @code{#f})
12349 A string containing a comma-separated list of one or more baud rates, in
12352 @item @code{term} (default: @code{#f})
12353 A string containing the value used for the @code{TERM} environment
12356 @item @code{eight-bits?} (default: @code{#f})
12357 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
12360 @item @code{auto-login} (default: @code{#f})
12361 When passed a login name, as a string, the specified user will be logged
12362 in automatically without prompting for their login name or password.
12364 @item @code{no-reset?} (default: @code{#f})
12365 When @code{#t}, don't reset terminal cflags (control modes).
12367 @item @code{host} (default: @code{#f})
12368 This accepts a string containing the "login_host", which will be written
12369 into the @file{/var/run/utmpx} file.
12371 @item @code{remote?} (default: @code{#f})
12372 When set to @code{#t} in conjunction with @var{host}, this will add an
12373 @code{-r} fakehost option to the command line of the login program
12374 specified in @var{login-program}.
12376 @item @code{flow-control?} (default: @code{#f})
12377 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
12379 @item @code{no-issue?} (default: @code{#f})
12380 When set to @code{#t}, the contents of the @file{/etc/issue} file will
12381 not be displayed before presenting the login prompt.
12383 @item @code{init-string} (default: @code{#f})
12384 This accepts a string that will be sent to the tty or modem before
12385 sending anything else. It can be used to initialize a modem.
12387 @item @code{no-clear?} (default: @code{#f})
12388 When set to @code{#t}, agetty will not clear the screen before showing
12391 @item @code{login-program} (default: (file-append shadow "/bin/login"))
12392 This must be either a gexp denoting the name of a log-in program, or
12393 unset, in which case the default value is the @command{login} from the
12396 @item @code{local-line} (default: @code{#f})
12397 Control the CLOCAL line flag. This accepts one of three symbols as
12398 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
12399 the default value chosen by agetty is @code{'auto}.
12401 @item @code{extract-baud?} (default: @code{#f})
12402 When set to @code{#t}, instruct agetty to try to extract the baud rate
12403 from the status messages produced by certain types of modems.
12405 @item @code{skip-login?} (default: @code{#f})
12406 When set to @code{#t}, do not prompt the user for a login name. This
12407 can be used with @var{login-program} field to use non-standard login
12410 @item @code{no-newline?} (default: @code{#f})
12411 When set to @code{#t}, do not print a newline before printing the
12412 @file{/etc/issue} file.
12414 @c Is this dangerous only when used with login-program, or always?
12415 @item @code{login-options} (default: @code{#f})
12416 This option accepts a string containing options that are passed to the
12417 login program. When used with the @var{login-program}, be aware that a
12418 malicious user could try to enter a login name containing embedded
12419 options that could be parsed by the login program.
12421 @item @code{login-pause} (default: @code{#f})
12422 When set to @code{#t}, wait for any key before showing the login prompt.
12423 This can be used in conjunction with @var{auto-login} to save memory by
12424 lazily spawning shells.
12426 @item @code{chroot} (default: @code{#f})
12427 Change root to the specified directory. This option accepts a directory
12430 @item @code{hangup?} (default: @code{#f})
12431 Use the Linux system call @code{vhangup} to do a virtual hangup of the
12432 specified terminal.
12434 @item @code{keep-baud?} (default: @code{#f})
12435 When set to @code{#t}, try to keep the existing baud rate. The baud
12436 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
12439 @item @code{timeout} (default: @code{#f})
12440 When set to an integer value, terminate if no user name could be read
12441 within @var{timeout} seconds.
12443 @item @code{detect-case?} (default: @code{#f})
12444 When set to @code{#t}, turn on support for detecting an uppercase-only
12445 terminal. This setting will detect a login name containing only
12446 uppercase letters as indicating an uppercase-only terminal and turn on
12447 some upper-to-lower case conversions. Note that this will not support
12448 Unicode characters.
12450 @item @code{wait-cr?} (default: @code{#f})
12451 When set to @code{#t}, wait for the user or modem to send a
12452 carriage-return or linefeed character before displaying
12453 @file{/etc/issue} or login prompt. This is typically used with the
12454 @var{init-string} option.
12456 @item @code{no-hints?} (default: @code{#f})
12457 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
12460 @item @code{no-hostname?} (default: @code{#f})
12461 By default, the hostname is printed. When this option is set to
12462 @code{#t}, no hostname will be shown at all.
12464 @item @code{long-hostname?} (default: @code{#f})
12465 By default, the hostname is only printed until the first dot. When this
12466 option is set to @code{#t}, the fully qualified hostname by
12467 @code{gethostname} or @code{getaddrinfo} is shown.
12469 @item @code{erase-characters} (default: @code{#f})
12470 This option accepts a string of additional characters that should be
12471 interpreted as backspace when the user types their login name.
12473 @item @code{kill-characters} (default: @code{#f})
12474 This option accepts a string that should be interpreted to mean "ignore
12475 all previous characters" (also called a "kill" character) when the user
12476 types their login name.
12478 @item @code{chdir} (default: @code{#f})
12479 This option accepts, as a string, a directory path that will be changed
12482 @item @code{delay} (default: @code{#f})
12483 This options accepts, as an integer, the number of seconds to sleep
12484 before opening the tty and displaying the login prompt.
12486 @item @code{nice} (default: @code{#f})
12487 This option accepts, as an integer, the nice value with which to run the
12488 @command{login} program.
12490 @item @code{extra-options} (default: @code{'()})
12491 This option provides an "escape hatch" for the user to provide arbitrary
12492 command-line arguments to @command{agetty} as a list of strings.
12497 @deffn {Scheme Procedure} kmscon-service-type @var{config}
12498 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
12499 according to @var{config}, a @code{<kmscon-configuration>} object, which
12500 specifies the tty to run, among other things.
12503 @deftp {Data Type} kmscon-configuration
12504 This is the data type representing the configuration of Kmscon, which
12505 implements virtual console log-in.
12509 @item @code{virtual-terminal}
12510 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
12512 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
12513 A gexp denoting the name of the log-in program. The default log-in program is
12514 @command{login} from the Shadow tool suite.
12516 @item @code{login-arguments} (default: @code{'("-p")})
12517 A list of arguments to pass to @command{login}.
12519 @item @code{auto-login} (default: @code{#f})
12520 When passed a login name, as a string, the specified user will be logged
12521 in automatically without prompting for their login name or password.
12523 @item @code{hardware-acceleration?} (default: #f)
12524 Whether to use hardware acceleration.
12526 @item @code{kmscon} (default: @var{kmscon})
12527 The Kmscon package to use.
12532 @cindex name service cache daemon
12534 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
12535 [#:name-services '()]
12536 Return a service that runs the libc name service cache daemon (nscd) with the
12537 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
12538 Service Switch}, for an example.
12540 For convenience, the Shepherd service for nscd provides the following actions:
12544 @cindex cache invalidation, nscd
12545 @cindex nscd, cache invalidation
12546 This invalidate the given cache. For instance, running:
12549 herd invalidate nscd hosts
12553 invalidates the host name lookup cache of nscd.
12556 Running @command{herd statistics nscd} displays information about nscd usage
12562 @defvr {Scheme Variable} %nscd-default-configuration
12563 This is the default @code{<nscd-configuration>} value (see below) used
12564 by @code{nscd-service}. It uses the caches defined by
12565 @var{%nscd-default-caches}; see below.
12568 @deftp {Data Type} nscd-configuration
12569 This is the data type representing the name service cache daemon (nscd)
12574 @item @code{name-services} (default: @code{'()})
12575 List of packages denoting @dfn{name services} that must be visible to
12576 the nscd---e.g., @code{(list @var{nss-mdns})}.
12578 @item @code{glibc} (default: @var{glibc})
12579 Package object denoting the GNU C Library providing the @command{nscd}
12582 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
12583 Name of the nscd log file. This is where debugging output goes when
12584 @code{debug-level} is strictly positive.
12586 @item @code{debug-level} (default: @code{0})
12587 Integer denoting the debugging levels. Higher numbers mean that more
12588 debugging output is logged.
12590 @item @code{caches} (default: @var{%nscd-default-caches})
12591 List of @code{<nscd-cache>} objects denoting things to be cached; see
12597 @deftp {Data Type} nscd-cache
12598 Data type representing a cache database of nscd and its parameters.
12602 @item @code{database}
12603 This is a symbol representing the name of the database to be cached.
12604 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
12605 @code{services}, which designate the corresponding NSS database
12606 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
12608 @item @code{positive-time-to-live}
12609 @itemx @code{negative-time-to-live} (default: @code{20})
12610 A number representing the number of seconds during which a positive or
12611 negative lookup result remains in cache.
12613 @item @code{check-files?} (default: @code{#t})
12614 Whether to check for updates of the files corresponding to
12617 For instance, when @var{database} is @code{hosts}, setting this flag
12618 instructs nscd to check for updates in @file{/etc/hosts} and to take
12621 @item @code{persistent?} (default: @code{#t})
12622 Whether the cache should be stored persistently on disk.
12624 @item @code{shared?} (default: @code{#t})
12625 Whether the cache should be shared among users.
12627 @item @code{max-database-size} (default: 32@tie{}MiB)
12628 Maximum size in bytes of the database cache.
12630 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
12631 @c settings, so leave them out.
12636 @defvr {Scheme Variable} %nscd-default-caches
12637 List of @code{<nscd-cache>} objects used by default by
12638 @code{nscd-configuration} (see above).
12640 It enables persistent and aggressive caching of service and host name
12641 lookups. The latter provides better host name lookup performance,
12642 resilience in the face of unreliable name servers, and also better
12643 privacy---often the result of host name lookups is in local cache, so
12644 external name servers do not even need to be queried.
12647 @anchor{syslog-configuration-type}
12650 @deftp {Data Type} syslog-configuration
12651 This data type represents the configuration of the syslog daemon.
12654 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12655 The syslog daemon to use.
12657 @item @code{config-file} (default: @code{%default-syslog.conf})
12658 The syslog configuration file to use.
12663 @anchor{syslog-service}
12665 @deffn {Scheme Procedure} syslog-service @var{config}
12666 Return a service that runs a syslog daemon according to @var{config}.
12668 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12669 information on the configuration file syntax.
12672 @defvr {Scheme Variable} guix-service-type
12673 This is the type of the service that runs the build daemon,
12674 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12675 @code{guix-configuration} record as described below.
12678 @anchor{guix-configuration-type}
12679 @deftp {Data Type} guix-configuration
12680 This data type represents the configuration of the Guix build daemon.
12681 @xref{Invoking guix-daemon}, for more information.
12684 @item @code{guix} (default: @var{guix})
12685 The Guix package to use.
12687 @item @code{build-group} (default: @code{"guixbuild"})
12688 Name of the group for build user accounts.
12690 @item @code{build-accounts} (default: @code{10})
12691 Number of build user accounts to create.
12693 @item @code{authorize-key?} (default: @code{#t})
12694 @cindex substitutes, authorization thereof
12695 Whether to authorize the substitute keys listed in
12696 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12697 (@pxref{Substitutes}).
12699 @vindex %default-authorized-guix-keys
12700 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12701 The list of authorized key files for archive imports, as a list of
12702 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12703 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12705 @item @code{use-substitutes?} (default: @code{#t})
12706 Whether to use substitutes.
12708 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12709 The list of URLs where to look for substitutes by default.
12711 @item @code{max-silent-time} (default: @code{0})
12712 @itemx @code{timeout} (default: @code{0})
12713 The number of seconds of silence and the number of seconds of activity,
12714 respectively, after which a build process times out. A value of zero
12715 disables the timeout.
12717 @item @code{log-compression} (default: @code{'bzip2})
12718 The type of compression used for build logs---one of @code{gzip},
12719 @code{bzip2}, or @code{none}.
12721 @item @code{extra-options} (default: @code{'()})
12722 List of extra command-line options for @command{guix-daemon}.
12724 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12725 File where @command{guix-daemon}'s standard output and standard error
12728 @item @code{http-proxy} (default: @code{#f})
12729 The HTTP proxy used for downloading fixed-output derivations and
12732 @item @code{tmpdir} (default: @code{#f})
12733 A directory path where the @command{guix-daemon} will perform builds.
12738 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12739 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12740 udev rules can be provided as a list of files through the @var{rules}
12741 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12742 @code{(gnu services base)} simplify the creation of such rule files.
12745 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12746 Return a udev-rule file named @var{file-name} containing the rules
12747 defined by the @var{contents} literal.
12749 In the following example, a rule for a USB device is defined to be
12750 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12751 upon detecting a USB device with a given product identifier.
12754 (define %example-udev-rule
12756 "90-usb-thing.rules"
12757 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12758 "ATTR@{product@}==\"Example\", "
12759 "RUN+=\"/path/to/script\"")))
12762 The @command{herd rules udev} command, as root, returns the name of the
12763 directory containing all the active udev rules.
12766 Here we show how the default @var{udev-service} can be extended with it.
12772 (modify-services %desktop-services
12773 (udev-service-type config =>
12774 (udev-configuration (inherit config)
12775 (rules (append (udev-configuration-rules config)
12776 (list %example-udev-rule))))))))
12779 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12780 Return a udev file named @var{file-name} containing the rules defined
12781 within @var{file}, a file-like object.
12783 The following example showcases how we can use an existing rule file.
12786 (use-modules (guix download) ;for url-fetch
12787 (guix packages) ;for origin
12790 (define %android-udev-rules
12792 "51-android-udev.rules"
12793 (let ((version "20170910"))
12796 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12797 "android-udev-rules/" version "/51-android.rules"))
12799 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12803 Additionally, Guix package definitions can be included in @var{rules} in
12804 order to extend the udev rules with the definitions found under their
12805 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12806 @var{file->udev-rule} example, we could have used the
12807 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12808 packages android)} module.
12810 The following example shows how to use the @var{android-udev-rules}
12811 package so that the Android tool @command{adb} can detect devices
12812 without root privileges. It also details how to create the
12813 @code{adbusers} group, which is required for the proper functioning of
12814 the rules defined within the @var{android-udev-rules} package. To
12815 create such a group, we must define it both as part of the
12816 @var{supplementary-groups} of our @var{user-account} declaration, as
12817 well as in the @var{groups} field of the @var{operating-system} record.
12820 (use-modules (gnu packages android) ;for android-udev-rules
12821 (gnu system shadow) ;for user-group
12826 (users (cons (user-acount
12828 (supplementary-groups
12829 '("adbusers" ;for adb
12830 "wheel" "netdev" "audio" "video")))))
12832 (groups (cons (user-group (system? #t) (name "adbusers"))
12838 (modify-services %desktop-services
12841 (udev-configuration (inherit config)
12842 (rules (cons android-udev-rules
12843 (udev-configuration-rules config))))))))
12846 @defvr {Scheme Variable} urandom-seed-service-type
12847 Save some entropy in @var{%random-seed-file} to seed @file{/dev/urandom}
12848 when rebooting. It also tries to seed @file{/dev/urandom} from
12849 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12853 @defvr {Scheme Variable} %random-seed-file
12854 This is the name of the file where some random bytes are saved by
12855 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12856 It defaults to @file{/var/lib/random-seed}.
12861 @defvr {Scheme Variable} gpm-service-type
12862 This is the type of the service that runs GPM, the @dfn{general-purpose
12863 mouse daemon}, which provides mouse support to the Linux console. GPM
12864 allows users to use the mouse in the console, notably to select, copy,
12867 The value for services of this type must be a @code{gpm-configuration}
12868 (see below). This service is not part of @code{%base-services}.
12871 @deftp {Data Type} gpm-configuration
12872 Data type representing the configuration of GPM.
12875 @item @code{options} (default: @code{%default-gpm-options})
12876 Command-line options passed to @command{gpm}. The default set of
12877 options instruct @command{gpm} to listen to mouse events on
12878 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12881 @item @code{gpm} (default: @code{gpm})
12882 The GPM package to use.
12887 @anchor{guix-publish-service-type}
12888 @deffn {Scheme Variable} guix-publish-service-type
12889 This is the service type for @command{guix publish} (@pxref{Invoking
12890 guix publish}). Its value must be a @code{guix-publish-configuration}
12891 object, as described below.
12893 This assumes that @file{/etc/guix} already contains a signing key pair as
12894 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12895 archive}). If that is not the case, the service will fail to start.
12898 @deftp {Data Type} guix-publish-configuration
12899 Data type representing the configuration of the @code{guix publish}
12903 @item @code{guix} (default: @code{guix})
12904 The Guix package to use.
12906 @item @code{port} (default: @code{80})
12907 The TCP port to listen for connections.
12909 @item @code{host} (default: @code{"localhost"})
12910 The host (and thus, network interface) to listen to. Use
12911 @code{"0.0.0.0"} to listen on all the network interfaces.
12913 @item @code{compression} (default: @code{'(("gzip" 3))})
12914 This is a list of compression method/level tuple used when compressing
12915 substitutes. For example, to compress all substitutes with @emph{both} lzip
12916 at level 7 and gzip at level 9, write:
12919 '(("lzip" 7) ("gzip" 9))
12922 Level 9 achieves the best compression ratio at the expense of increased CPU
12923 usage, whereas level 1 achieves fast compression.
12925 An empty list disables compression altogether.
12927 @item @code{nar-path} (default: @code{"nar"})
12928 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
12929 publish, @code{--nar-path}}, for details.
12931 @item @code{cache} (default: @code{#f})
12932 When it is @code{#f}, disable caching and instead generate archives on
12933 demand. Otherwise, this should be the name of a directory---e.g.,
12934 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
12935 archives and meta-data ready to be sent. @xref{Invoking guix publish,
12936 @option{--cache}}, for more information on the tradeoffs involved.
12938 @item @code{workers} (default: @code{#f})
12939 When it is an integer, this is the number of worker threads used for
12940 caching; when @code{#f}, the number of processors is used.
12941 @xref{Invoking guix publish, @option{--workers}}, for more information.
12943 @item @code{ttl} (default: @code{#f})
12944 When it is an integer, this denotes the @dfn{time-to-live} in seconds
12945 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
12946 for more information.
12950 @anchor{rngd-service}
12951 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
12952 [#:device "/dev/hwrng"]
12953 Return a service that runs the @command{rngd} program from @var{rng-tools}
12954 to add @var{device} to the kernel's entropy pool. The service will fail if
12955 @var{device} does not exist.
12958 @anchor{pam-limits-service}
12959 @cindex session limits
12964 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
12966 Return a service that installs a configuration file for the
12967 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
12968 @code{pam_limits} module}. The procedure optionally takes a list of
12969 @code{pam-limits-entry} values, which can be used to specify
12970 @code{ulimit} limits and nice priority limits to user sessions.
12972 The following limits definition sets two hard and soft limits for all
12973 login sessions of users in the @code{realtime} group:
12976 (pam-limits-service
12978 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
12979 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
12982 The first entry increases the maximum realtime priority for
12983 non-privileged processes; the second entry lifts any restriction of the
12984 maximum address space that can be locked in memory. These settings are
12985 commonly used for real-time audio systems.
12988 @node Scheduled Job Execution
12989 @subsection Scheduled Job Execution
12993 @cindex scheduling jobs
12994 The @code{(gnu services mcron)} module provides an interface to
12995 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
12996 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
12997 Unix @command{cron} daemon; the main difference is that it is
12998 implemented in Guile Scheme, which provides a lot of flexibility when
12999 specifying the scheduling of jobs and their actions.
13001 The example below defines an operating system that runs the
13002 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
13003 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
13004 well as the @command{mkid} command on behalf of an unprivileged user
13005 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
13006 gexps to introduce job definitions that are passed to mcron
13007 (@pxref{G-Expressions}).
13010 (use-modules (guix) (gnu) (gnu services mcron))
13011 (use-package-modules base idutils)
13013 (define updatedb-job
13014 ;; Run 'updatedb' at 3AM every day. Here we write the
13015 ;; job's action as a Scheme procedure.
13016 #~(job '(next-hour '(3))
13018 (execl (string-append #$findutils "/bin/updatedb")
13020 "--prunepaths=/tmp /var/tmp /gnu/store"))))
13022 (define garbage-collector-job
13023 ;; Collect garbage 5 minutes after midnight every day.
13024 ;; The job's action is a shell command.
13025 #~(job "5 0 * * *" ;Vixie cron syntax
13028 (define idutils-job
13029 ;; Update the index database as user "charlie" at 12:15PM
13030 ;; and 19:15PM. This runs from the user's home directory.
13031 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
13032 (string-append #$idutils "/bin/mkid src")
13037 (services (cons (service mcron-service-type
13038 (mcron-configuration
13039 (jobs (list garbage-collector-job
13045 For more complex jobs defined in Scheme where you need control over the top
13046 level, for instance to introduce a @code{use-modules} form, you can move your
13047 code to a separate program using the @code{program-file} procedure of the
13048 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
13052 (define %battery-alert-job
13053 ;; Beep when the battery percentage falls below %MIN-LEVEL.
13055 '(next-minute (range 0 60 1))
13057 "battery-alert.scm"
13058 (with-imported-modules (source-module-closure
13059 '((guix build utils)))
13061 (define %min-level 20)
13062 (use-modules (guix build utils)
13065 (ice-9 textual-ports)
13067 (setenv "LC_ALL" "C") ;ensure English output
13068 (and-let* ((input-pipe (open-pipe*
13070 #$(file-append acpi "/bin/acpi")))
13071 (output (get-string-all input-pipe))
13072 (m (string-match "Discharging, ([0-9]+)%" output))
13073 (level (string->number (match:substring m 1)))
13074 ((< level %min-level)))
13075 (format #t "warning: Battery level is low (~a%)~%" level)
13076 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
13079 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
13080 for more information on mcron job specifications. Below is the
13081 reference of the mcron service.
13083 On a running system, you can use the @code{schedule} action of the service to
13084 visualize the mcron jobs that will be executed next:
13087 # herd schedule mcron
13091 The example above lists the next five tasks that will be executed, but you can
13092 also specify the number of tasks to display:
13095 # herd schedule mcron 10
13098 @defvr {Scheme Variable} mcron-service-type
13099 This is the type of the @code{mcron} service, whose value is an
13100 @code{mcron-configuration} object.
13102 This service type can be the target of a service extension that provides
13103 it additional job specifications (@pxref{Service Composition}). In
13104 other words, it is possible to define services that provide additional
13108 @deftp {Data Type} mcron-configuration
13109 Data type representing the configuration of mcron.
13112 @item @code{mcron} (default: @var{mcron})
13113 The mcron package to use.
13116 This is a list of gexps (@pxref{G-Expressions}), where each gexp
13117 corresponds to an mcron job specification (@pxref{Syntax, mcron job
13118 specifications,, mcron, GNU@tie{}mcron}).
13124 @subsection Log Rotation
13127 @cindex log rotation
13129 Log files such as those found in @file{/var/log} tend to grow endlessly,
13130 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
13131 their contents in separate files, possibly compressed. The @code{(gnu
13132 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
13133 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
13135 The example below defines an operating system that provides log rotation
13136 with the default settings, for commonly encountered log files.
13139 (use-modules (guix) (gnu))
13140 (use-service-modules admin mcron)
13141 (use-package-modules base idutils)
13145 (services (cons (service rottlog-service-type)
13149 @defvr {Scheme Variable} rottlog-service-type
13150 This is the type of the Rottlog service, whose value is a
13151 @code{rottlog-configuration} object.
13153 Other services can extend this one with new @code{log-rotation} objects
13154 (see below), thereby augmenting the set of files to be rotated.
13156 This service type can define mcron jobs (@pxref{Scheduled Job
13157 Execution}) to run the rottlog service.
13160 @deftp {Data Type} rottlog-configuration
13161 Data type representing the configuration of rottlog.
13164 @item @code{rottlog} (default: @code{rottlog})
13165 The Rottlog package to use.
13167 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
13168 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
13169 rottlog, GNU Rot[t]log Manual}).
13171 @item @code{rotations} (default: @code{%default-rotations})
13172 A list of @code{log-rotation} objects as defined below.
13175 This is a list of gexps where each gexp corresponds to an mcron job
13176 specification (@pxref{Scheduled Job Execution}).
13180 @deftp {Data Type} log-rotation
13181 Data type representing the rotation of a group of log files.
13183 Taking an example from the Rottlog manual (@pxref{Period Related File
13184 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
13190 (files '("/var/log/apache/*"))
13191 (options '("storedir apache-archives"
13197 The list of fields is as follows:
13200 @item @code{frequency} (default: @code{'weekly})
13201 The log rotation frequency, a symbol.
13204 The list of files or file glob patterns to rotate.
13206 @item @code{options} (default: @code{'()})
13207 The list of rottlog options for this rotation (@pxref{Configuration
13208 parameters,,, rottlog, GNU Rot[t]lg Manual}).
13210 @item @code{post-rotate} (default: @code{#f})
13211 Either @code{#f} or a gexp to execute once the rotation has completed.
13215 @defvr {Scheme Variable} %default-rotations
13216 Specifies weekly rotation of @var{%rotated-files} and of
13217 @file{/var/log/guix-daemon.log}.
13220 @defvr {Scheme Variable} %rotated-files
13221 The list of syslog-controlled files to be rotated. By default it is:
13222 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
13223 "/var/log/maillog")}.
13226 @node Networking Services
13227 @subsection Networking Services
13229 The @code{(gnu services networking)} module provides services to configure
13230 the network interface.
13232 @cindex DHCP, networking service
13233 @defvr {Scheme Variable} dhcp-client-service-type
13234 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
13235 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
13236 is the DHCP client package to use, @code{isc-dhcp} by default.
13239 @deffn {Scheme Procedure} dhcpd-service-type
13240 This type defines a service that runs a DHCP daemon. To create a
13241 service of this type, you must supply a @code{<dhcpd-configuration>}.
13245 (service dhcpd-service-type
13246 (dhcpd-configuration
13247 (config-file (local-file "my-dhcpd.conf"))
13248 (interfaces '("enp0s25"))))
13252 @deftp {Data Type} dhcpd-configuration
13254 @item @code{package} (default: @code{isc-dhcp})
13255 The package that provides the DHCP daemon. This package is expected to
13256 provide the daemon at @file{sbin/dhcpd} relative to its output
13257 directory. The default package is the
13258 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
13259 @item @code{config-file} (default: @code{#f})
13260 The configuration file to use. This is required. It will be passed to
13261 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
13262 object (@pxref{G-Expressions, file-like objects}). See @code{man
13263 dhcpd.conf} for details on the configuration file syntax.
13264 @item @code{version} (default: @code{"4"})
13265 The DHCP version to use. The ISC DHCP server supports the values ``4'',
13266 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
13267 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
13269 @item @code{run-directory} (default: @code{"/run/dhcpd"})
13270 The run directory to use. At service activation time, this directory
13271 will be created if it does not exist.
13272 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
13273 The PID file to use. This corresponds to the @code{-pf} option of
13274 @code{dhcpd}. See @code{man dhcpd} for details.
13275 @item @code{interfaces} (default: @code{'()})
13276 The names of the network interfaces on which dhcpd should listen for
13277 broadcasts. If this list is not empty, then its elements (which must be
13278 strings) will be appended to the @code{dhcpd} invocation when starting
13279 the daemon. It may not be necessary to explicitly specify any
13280 interfaces here; see @code{man dhcpd} for details.
13284 @defvr {Scheme Variable} static-networking-service-type
13285 This is the type for statically-configured network interfaces.
13286 @c TODO Document <static-networking> data structures.
13289 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
13290 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
13291 [#:requirement @code{'(udev)}]
13292 Return a service that starts @var{interface} with address @var{ip}. If
13293 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
13294 it must be a string specifying the default network gateway. @var{requirement}
13295 can be used to declare a dependency on another service before configuring the
13298 This procedure can be called several times, one for each network
13299 interface of interest. Behind the scenes what it does is extend
13300 @code{static-networking-service-type} with additional network interfaces
13306 (static-networking-service "eno1" "192.168.1.82"
13307 #:gateway "192.168.1.2"
13308 #:name-servers '("192.168.1.2"))
13315 @cindex network management
13316 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
13317 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
13318 management daemon that aims to simplify wired and wireless networking.
13320 This service adds the @var{wicd} package to the global profile, providing
13321 several commands to interact with the daemon and configure networking:
13322 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
13323 and @command{wicd-curses} user interfaces.
13326 @cindex ModemManager
13328 @defvr {Scheme Variable} modem-manager-service-type
13329 This is the service type for the
13330 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
13331 service. The value for this service type is a
13332 @code{modem-manager-configuration} record.
13334 This service is part of @code{%desktop-services} (@pxref{Desktop
13338 @deftp {Data Type} modem-manager-configuration
13339 Data type representing the configuration of ModemManager.
13342 @item @code{modem-manager} (default: @code{modem-manager})
13343 The ModemManager package to use.
13348 @cindex USB_ModeSwitch
13349 @cindex Modeswitching
13351 @defvr {Scheme Variable} usb-modeswitch-service-type
13352 This is the service type for the
13353 @uref{http://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
13354 value for this service type is a @code{usb-modeswitch-configuration} record.
13356 When plugged in, some USB modems (and other USB devices) initially present
13357 themselves as a read-only storage medium and not as a modem. They need to be
13358 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
13359 installs udev rules to automatically modeswitch these devices when they are
13362 This service is part of @code{%desktop-services} (@pxref{Desktop
13366 @deftp {Data Type} usb-modeswitch-configuration
13367 Data type representing the configuration of USB_ModeSwitch.
13370 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
13371 The USB_ModeSwitch package providing the binaries for modeswitching.
13373 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
13374 The package providing the device data and udev rules file used by
13377 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
13378 Which config file to use for the USB_ModeSwitch dispatcher. By default the
13379 config file shipped with USB_ModeSwitch is used which disables logging to
13380 @file{/var/log} among other default settings. If set to @code{#f}, no config
13386 @cindex NetworkManager
13388 @defvr {Scheme Variable} network-manager-service-type
13389 This is the service type for the
13390 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
13391 service. The value for this service type is a
13392 @code{network-manager-configuration} record.
13394 This service is part of @code{%desktop-services} (@pxref{Desktop
13398 @deftp {Data Type} network-manager-configuration
13399 Data type representing the configuration of NetworkManager.
13402 @item @code{network-manager} (default: @code{network-manager})
13403 The NetworkManager package to use.
13405 @item @code{dns} (default: @code{"default"})
13406 Processing mode for DNS, which affects how NetworkManager uses the
13407 @code{resolv.conf} configuration file.
13411 NetworkManager will update @code{resolv.conf} to reflect the nameservers
13412 provided by currently active connections.
13415 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
13416 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
13417 then update @code{resolv.conf} to point to the local nameserver.
13419 With this setting, you can share your network connection. For example when
13420 you want to share your network connection to another laptop @i{via} an
13421 Ethernet cable, you can open @command{nm-connection-editor} and configure the
13422 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
13423 and reestablish the connection (or reboot).
13425 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
13426 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
13427 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
13428 browser on your host system, or connect to the VM @i{via} SSH
13429 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
13430 host-to-guest connection, run this command once:
13433 nmcli connection add type tun \
13434 connection.interface-name tap0 \
13435 tun.mode tap tun.owner $(id -u) \
13436 ipv4.method shared \
13437 ipv4.addresses 172.28.112.1/24
13440 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
13441 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
13442 @command{qemu-system-...}.
13445 NetworkManager will not modify @code{resolv.conf}.
13448 @item @code{vpn-plugins} (default: @code{'()})
13449 This is the list of available plugins for virtual private networks
13450 (VPNs). An example of this is the @code{network-manager-openvpn}
13451 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
13457 @deffn {Scheme Variable} connman-service-type
13458 This is the service type to run @url{https://01.org/connman,Connman},
13459 a network connection manager.
13461 Its value must be an
13462 @code{connman-configuration} record as in this example:
13465 (service connman-service-type
13466 (connman-configuration
13467 (disable-vpn? #t)))
13470 See below for details about @code{connman-configuration}.
13473 @deftp {Data Type} connman-configuration
13474 Data Type representing the configuration of connman.
13477 @item @code{connman} (default: @var{connman})
13478 The connman package to use.
13480 @item @code{disable-vpn?} (default: @code{#f})
13481 When true, disable connman's vpn plugin.
13485 @cindex WPA Supplicant
13486 @defvr {Scheme Variable} wpa-supplicant-service-type
13487 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
13488 supplicant}, an authentication daemon required to authenticate against
13489 encrypted WiFi or ethernet networks.
13492 @deftp {Data Type} wpa-supplicant-configuration
13493 Data type representing the configuration of WPA Supplicant.
13495 It takes the following parameters:
13498 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
13499 The WPA Supplicant package to use.
13501 @item @code{dbus?} (default: @code{#t})
13502 Whether to listen for requests on D-Bus.
13504 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
13505 Where to store the PID file.
13507 @item @code{interface} (default: @code{#f})
13508 If this is set, it must specify the name of a network interface that
13509 WPA supplicant will control.
13511 @item @code{config-file} (default: @code{#f})
13512 Optional configuration file to use.
13514 @item @code{extra-options} (default: @code{'()})
13515 List of additional command-line arguments to pass to the daemon.
13520 @defvr {Scheme Variable} iptables-service-type
13521 This is the service type to set up an iptables configuration. iptables is a
13522 packet filtering framework supported by the Linux kernel. This service
13523 supports configuring iptables for both IPv4 and IPv6. A simple example
13524 configuration rejecting all incoming connections except those to the ssh port
13528 (service iptables-service-type
13529 (iptables-configuration
13530 (ipv4-rules (plain-file "iptables.rules" "*filter
13534 -A INPUT -p tcp --dport 22 -j ACCEPT
13535 -A INPUT -j REJECT --reject-with icmp-port-unreachable
13538 (ipv6-rules (plain-file "ip6tables.rules" "*filter
13542 -A INPUT -p tcp --dport 22 -j ACCEPT
13543 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
13549 @deftp {Data Type} iptables-configuration
13550 The data type representing the configuration of iptables.
13553 @item @code{iptables} (default: @code{iptables})
13554 The iptables package that provides @code{iptables-restore} and
13555 @code{ip6tables-restore}.
13556 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
13557 The iptables rules to use. It will be passed to @code{iptables-restore}.
13558 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13560 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
13561 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
13562 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13568 @defvr {Scheme Variable} nftables-service-type
13569 This is the service type to set up a nftables configuration. nftables is a
13570 netfilter project that aims to replace the existing iptables, ip6tables,
13571 arptables and ebtables framework. It provides a new packet filtering
13572 framework, a new user-space utility @command{nft}, and a compatibility layer
13573 for iptables. This service comes with a default ruleset
13574 @code{%default-nftables-ruleset} that rejecting all incomming connections
13575 except those to the ssh port 22. To use it, simply write:
13578 (service nftables-service-type)
13582 @deftp {Data Type} nftables-configuration
13583 The data type representing the configuration of nftables.
13586 @item @code{package} (default: @code{nftables})
13587 The nftables package that provides @command{nft}.
13588 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
13589 The nftables ruleset to use. This may be any ``file-like'' object
13590 (@pxref{G-Expressions, file-like objects}).
13594 @cindex NTP (Network Time Protocol), service
13595 @cindex ntpd, service for the Network Time Protocol daemon
13596 @cindex real time clock
13597 @defvr {Scheme Variable} ntp-service-type
13598 This is the type of the service running the @uref{http://www.ntp.org,
13599 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
13600 system clock synchronized with that of the specified NTP servers.
13602 The value of this service is an @code{ntpd-configuration} object, as described
13606 @deftp {Data Type} ntp-configuration
13607 This is the data type for the NTP service configuration.
13610 @item @code{servers} (default: @code{%ntp-servers})
13611 This is the list of servers (@code{<ntp-server>} records) with which
13612 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
13615 @item @code{allow-large-adjustment?} (default: @code{#t})
13616 This determines whether @command{ntpd} is allowed to make an initial
13617 adjustment of more than 1,000 seconds.
13619 @item @code{ntp} (default: @code{ntp})
13620 The NTP package to use.
13624 @defvr {Scheme Variable} %ntp-servers
13625 List of host names used as the default NTP servers. These are servers of the
13626 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
13629 @deftp {Data Type} ntp-server
13630 The data type representing the configuration of a NTP server.
13633 @item @code{type} (default: @code{'server})
13634 The type of the NTP server, given as a symbol. One of @code{'pool},
13635 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
13637 @item @code{address}
13638 The address of the server, as a string.
13640 @item @code{options}
13641 NTPD options to use with that specific server, given as a list of option names
13642 and/or of option names and values tuples. The following example define a server
13643 to use with the options @option{iburst} and @option{prefer}, as well as
13644 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
13649 (address "some.ntp.server.org")
13650 (options `(iburst (version 3) (maxpoll 16) prefer))))
13656 @deffn {Scheme Procedure} openntpd-service-type
13657 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
13658 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
13659 clock synchronized with that of the given servers.
13663 openntpd-service-type
13664 (openntpd-configuration
13665 (listen-on '("127.0.0.1" "::1"))
13666 (sensor '("udcf0 correction 70000"))
13667 (constraint-from '("www.gnu.org"))
13668 (constraints-from '("https://www.google.com/"))
13669 (allow-large-adjustment? #t)))
13674 @defvr {Scheme Variable} %openntpd-servers
13675 This variable is a list of the server addresses defined in
13676 @var{%ntp-servers}.
13679 @deftp {Data Type} openntpd-configuration
13681 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
13682 The openntpd executable to use.
13683 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
13684 A list of local IP addresses or hostnames the ntpd daemon should listen on.
13685 @item @code{query-from} (default: @code{'()})
13686 A list of local IP address the ntpd daemon should use for outgoing queries.
13687 @item @code{sensor} (default: @code{'()})
13688 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
13689 will listen to each sensor that actually exists and ignore non-existent ones.
13690 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
13692 @item @code{server} (default: @code{'()})
13693 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
13694 @item @code{servers} (default: @var{%openntp-servers})
13695 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
13696 @item @code{constraint-from} (default: @code{'()})
13697 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
13698 This time information is not used for precision but acts as an authenticated
13699 constraint, thereby reducing the impact of unauthenticated NTP
13700 man-in-the-middle attacks.
13701 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
13703 @item @code{constraints-from} (default: @code{'()})
13704 As with constraint from, specify a list of URLs, IP addresses or hostnames of
13705 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
13706 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
13707 @item @code{allow-large-adjustment?} (default: @code{#f})
13708 Determines if @code{ntpd} is allowed to make an initial adjustment of more
13714 @deffn {Scheme variable} inetd-service-type
13715 This service runs the @command{inetd} (@pxref{inetd invocation,,,
13716 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
13717 connections on internet sockets, and lazily starts the specified server
13718 program when a connection is made on one of these sockets.
13720 The value of this service is an @code{inetd-configuration} object. The
13721 following example configures the @command{inetd} daemon to provide the
13722 built-in @command{echo} service, as well as an smtp service which
13723 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
13724 gateway @code{hostname}:
13729 (inetd-configuration
13733 (socket-type 'stream)
13740 (socket-type 'stream)
13744 (program (file-append openssh "/bin/ssh"))
13746 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13747 "-W" "smtp-server:25" "user@@hostname")))))))
13750 See below for more details about @code{inetd-configuration}.
13753 @deftp {Data Type} inetd-configuration
13754 Data type representing the configuration of @command{inetd}.
13757 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13758 The @command{inetd} executable to use.
13760 @item @code{entries} (default: @code{'()})
13761 A list of @command{inetd} service entries. Each entry should be created
13762 by the @code{inetd-entry} constructor.
13766 @deftp {Data Type} inetd-entry
13767 Data type representing an entry in the @command{inetd} configuration.
13768 Each entry corresponds to a socket where @command{inetd} will listen for
13772 @item @code{node} (default: @code{#f})
13773 Optional string, a comma-separated list of local addresses
13774 @command{inetd} should use when listening for this service.
13775 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13776 description of all options.
13778 A string, the name must correspond to an entry in @code{/etc/services}.
13779 @item @code{socket-type}
13780 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13782 @item @code{protocol}
13783 A string, must correspond to an entry in @code{/etc/protocols}.
13784 @item @code{wait?} (default: @code{#t})
13785 Whether @command{inetd} should wait for the server to exit before
13786 listening to new service requests.
13788 A string containing the user (and, optionally, group) name of the user
13789 as whom the server should run. The group name can be specified in a
13790 suffix, separated by a colon or period, i.e.@: @code{"user"},
13791 @code{"user:group"} or @code{"user.group"}.
13792 @item @code{program} (default: @code{"internal"})
13793 The server program which will serve the requests, or @code{"internal"}
13794 if @command{inetd} should use a built-in service.
13795 @item @code{arguments} (default: @code{'()})
13796 A list strings or file-like objects, which are the server program's
13797 arguments, starting with the zeroth argument, i.e.@: the name of the
13798 program itself. For @command{inetd}'s internal services, this entry
13799 must be @code{'()} or @code{'("internal")}.
13802 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13803 detailed discussion of each configuration field.
13807 @defvr {Scheme Variable} tor-service-type
13808 This is the type for a service that runs the @uref{https://torproject.org,
13809 Tor} anonymous networking daemon. The service is configured using a
13810 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
13811 @code{tor} unprivileged user, which is a member of the @code{tor} group.
13815 @deftp {Data Type} tor-configuration
13817 @item @code{tor} (default: @code{tor})
13818 The package that provides the Tor daemon. This package is expected to provide
13819 the daemon at @file{bin/tor} relative to its output directory. The default
13820 package is the @uref{https://www.torproject.org, Tor Project's}
13823 @item @code{config-file} (default: @code{(plain-file "empty" "")})
13824 The configuration file to use. It will be appended to a default configuration
13825 file, and the final configuration file will be passed to @code{tor} via its
13826 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
13827 file-like objects}). See @code{man tor} for details on the configuration file
13830 @item @code{hidden-services} (default: @code{'()})
13831 The list of @code{<hidden-service>} records to use. For any hidden service
13832 you include in this list, appropriate configuration to enable the hidden
13833 service will be automatically added to the default configuration file. You
13834 may conveniently create @code{<hidden-service>} records using the
13835 @code{tor-hidden-service} procedure described below.
13837 @item @code{socks-socket-type} (default: @code{'tcp})
13838 The default socket type that Tor should use for its SOCKS socket. This must
13839 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
13840 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
13841 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
13842 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13845 If you want to customize the SOCKS socket in more detail, leave
13846 @code{socks-socket-type} at its default value of @code{'tcp} and use
13847 @code{config-file} to override the default by providing your own
13848 @code{SocksPort} option.
13852 @cindex hidden service
13853 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13854 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13855 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13858 '((22 "127.0.0.1:22")
13859 (80 "127.0.0.1:8080"))
13862 In this example, port 22 of the hidden service is mapped to local port 22, and
13863 port 80 is mapped to local port 8080.
13865 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13866 the @file{hostname} file contains the @code{.onion} host name for the hidden
13869 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13870 project's documentation} for more information.
13873 The @code{(gnu services rsync)} module provides the following services:
13875 You might want an rsync daemon if you have files that you want available
13876 so anyone (or just yourself) can download existing files or upload new
13879 @deffn {Scheme Variable} rsync-service-type
13880 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13881 The value for this service type is a
13882 @command{rsync-configuration} record as in this example:
13885 (service rsync-service-type)
13888 See below for details about @code{rsync-configuration}.
13891 @deftp {Data Type} rsync-configuration
13892 Data type representing the configuration for @code{rsync-service}.
13895 @item @code{package} (default: @var{rsync})
13896 @code{rsync} package to use.
13898 @item @code{port-number} (default: @code{873})
13899 TCP port on which @command{rsync} listens for incoming connections. If port
13900 is less than @code{1024} @command{rsync} needs to be started as the
13901 @code{root} user and group.
13903 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
13904 Name of the file where @command{rsync} writes its PID.
13906 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
13907 Name of the file where @command{rsync} writes its lock file.
13909 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
13910 Name of the file where @command{rsync} writes its log file.
13912 @item @code{use-chroot?} (default: @var{#t})
13913 Whether to use chroot for @command{rsync} shared directory.
13915 @item @code{share-path} (default: @file{/srv/rsync})
13916 Location of the @command{rsync} shared directory.
13918 @item @code{share-comment} (default: @code{"Rsync share"})
13919 Comment of the @command{rsync} shared directory.
13921 @item @code{read-only?} (default: @var{#f})
13922 Read-write permissions to shared directory.
13924 @item @code{timeout} (default: @code{300})
13925 I/O timeout in seconds.
13927 @item @code{user} (default: @var{"root"})
13928 Owner of the @code{rsync} process.
13930 @item @code{group} (default: @var{"root"})
13931 Group of the @code{rsync} process.
13933 @item @code{uid} (default: @var{"rsyncd"})
13934 User name or user ID that file transfers to and from that module should take
13935 place as when the daemon was run as @code{root}.
13937 @item @code{gid} (default: @var{"rsyncd"})
13938 Group name or group ID that will be used when accessing the module.
13943 Furthermore, @code{(gnu services ssh)} provides the following services.
13947 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
13948 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
13949 [#:allow-empty-passwords? #f] [#:root-login? #f] @
13950 [#:syslog-output? #t] [#:x11-forwarding? #t] @
13951 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
13952 [#:public-key-authentication? #t] [#:initialize? #t]
13953 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
13954 @var{host-key} must designate a file containing the host key, and readable
13957 When @var{daemonic?} is true, @command{lshd} will detach from the
13958 controlling terminal and log its output to syslogd, unless one sets
13959 @var{syslog-output?} to false. Obviously, it also makes lsh-service
13960 depend on existence of syslogd service. When @var{pid-file?} is true,
13961 @command{lshd} writes its PID to the file called @var{pid-file}.
13963 When @var{initialize?} is true, automatically create the seed and host key
13964 upon service activation if they do not exist yet. This may take long and
13965 require interaction.
13967 When @var{initialize?} is false, it is up to the user to initialize the
13968 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
13969 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
13970 basics,,, lsh, LSH Manual}).
13972 When @var{interfaces} is empty, lshd listens for connections on all the
13973 network interfaces; otherwise, @var{interfaces} must be a list of host names
13976 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
13977 passwords, and @var{root-login?} specifies whether to accept log-ins as
13980 The other options should be self-descriptive.
13985 @deffn {Scheme Variable} openssh-service-type
13986 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
13987 shell daemon, @command{sshd}. Its value must be an
13988 @code{openssh-configuration} record as in this example:
13991 (service openssh-service-type
13992 (openssh-configuration
13993 (x11-forwarding? #t)
13994 (permit-root-login 'without-password)
13996 `(("alice" ,(local-file "alice.pub"))
13997 ("bob" ,(local-file "bob.pub"))))))
14000 See below for details about @code{openssh-configuration}.
14002 This service can be extended with extra authorized keys, as in this
14006 (service-extension openssh-service-type
14007 (const `(("charlie"
14008 ,(local-file "charlie.pub")))))
14012 @deftp {Data Type} openssh-configuration
14013 This is the configuration record for OpenSSH's @command{sshd}.
14016 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
14017 Name of the file where @command{sshd} writes its PID.
14019 @item @code{port-number} (default: @code{22})
14020 TCP port on which @command{sshd} listens for incoming connections.
14022 @item @code{permit-root-login} (default: @code{#f})
14023 This field determines whether and when to allow logins as root. If
14024 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
14025 If it's the symbol @code{'without-password}, then root logins are
14026 permitted but not with password-based authentication.
14028 @item @code{allow-empty-passwords?} (default: @code{#f})
14029 When true, users with empty passwords may log in. When false, they may
14032 @item @code{password-authentication?} (default: @code{#t})
14033 When true, users may log in with their password. When false, they have
14034 other authentication methods.
14036 @item @code{public-key-authentication?} (default: @code{#t})
14037 When true, users may log in using public key authentication. When
14038 false, users have to use other authentication method.
14040 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
14041 This is used only by protocol version 2.
14043 @item @code{x11-forwarding?} (default: @code{#f})
14044 When true, forwarding of X11 graphical client connections is
14045 enabled---in other words, @command{ssh} options @option{-X} and
14046 @option{-Y} will work.
14048 @item @code{allow-agent-forwarding?} (default: @code{#t})
14049 Whether to allow agent forwarding.
14051 @item @code{allow-tcp-forwarding?} (default: @code{#t})
14052 Whether to allow TCP forwarding.
14054 @item @code{gateway-ports?} (default: @code{#f})
14055 Whether to allow gateway ports.
14057 @item @code{challenge-response-authentication?} (default: @code{#f})
14058 Specifies whether challenge response authentication is allowed (e.g.@: via
14061 @item @code{use-pam?} (default: @code{#t})
14062 Enables the Pluggable Authentication Module interface. If set to
14063 @code{#t}, this will enable PAM authentication using
14064 @code{challenge-response-authentication?} and
14065 @code{password-authentication?}, in addition to PAM account and session
14066 module processing for all authentication types.
14068 Because PAM challenge response authentication usually serves an
14069 equivalent role to password authentication, you should disable either
14070 @code{challenge-response-authentication?} or
14071 @code{password-authentication?}.
14073 @item @code{print-last-log?} (default: @code{#t})
14074 Specifies whether @command{sshd} should print the date and time of the
14075 last user login when a user logs in interactively.
14077 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
14078 Configures external subsystems (e.g.@: file transfer daemon).
14080 This is a list of two-element lists, each of which containing the
14081 subsystem name and a command (with optional arguments) to execute upon
14084 The command @command{internal-sftp} implements an in-process SFTP
14085 server. Alternately, one can specify the @command{sftp-server} command:
14087 (service openssh-service-type
14088 (openssh-configuration
14090 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
14093 @item @code{accepted-environment} (default: @code{'()})
14094 List of strings describing which environment variables may be exported.
14096 Each string gets on its own line. See the @code{AcceptEnv} option in
14097 @code{man sshd_config}.
14099 This example allows ssh-clients to export the @code{COLORTERM} variable.
14100 It is set by terminal emulators, which support colors. You can use it in
14101 your shell's ressource file to enable colors for the prompt and commands
14102 if this variable is set.
14105 (service openssh-service-type
14106 (openssh-configuration
14107 (accepted-environment '("COLORTERM"))))
14110 @item @code{authorized-keys} (default: @code{'()})
14111 @cindex authorized keys, SSH
14112 @cindex SSH authorized keys
14113 This is the list of authorized keys. Each element of the list is a user
14114 name followed by one or more file-like objects that represent SSH public
14118 (openssh-configuration
14120 `(("rekado" ,(local-file "rekado.pub"))
14121 ("chris" ,(local-file "chris.pub"))
14122 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
14126 registers the specified public keys for user accounts @code{rekado},
14127 @code{chris}, and @code{root}.
14129 Additional authorized keys can be specified @i{via}
14130 @code{service-extension}.
14132 Note that this does @emph{not} interfere with the use of
14133 @file{~/.ssh/authorized_keys}.
14135 @item @code{log-level} (default: @code{'info})
14136 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
14137 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
14138 page for @file{sshd_config} for the full list of level names.
14140 @item @code{extra-content} (default: @code{""})
14141 This field can be used to append arbitrary text to the configuration file. It
14142 is especially useful for elaborate configurations that cannot be expressed
14143 otherwise. This configuration, for example, would generally disable root
14144 logins, but permit them from one specific IP address:
14147 (openssh-configuration
14149 Match Address 192.168.0.1
14150 PermitRootLogin yes"))
14156 @deffn {Scheme Procedure} dropbear-service [@var{config}]
14157 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
14158 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
14161 For example, to specify a Dropbear service listening on port 1234, add
14162 this call to the operating system's @code{services} field:
14165 (dropbear-service (dropbear-configuration
14166 (port-number 1234)))
14170 @deftp {Data Type} dropbear-configuration
14171 This data type represents the configuration of a Dropbear SSH daemon.
14174 @item @code{dropbear} (default: @var{dropbear})
14175 The Dropbear package to use.
14177 @item @code{port-number} (default: 22)
14178 The TCP port where the daemon waits for incoming connections.
14180 @item @code{syslog-output?} (default: @code{#t})
14181 Whether to enable syslog output.
14183 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
14184 File name of the daemon's PID file.
14186 @item @code{root-login?} (default: @code{#f})
14187 Whether to allow @code{root} logins.
14189 @item @code{allow-empty-passwords?} (default: @code{#f})
14190 Whether to allow empty passwords.
14192 @item @code{password-authentication?} (default: @code{#t})
14193 Whether to enable password-based authentication.
14197 @defvr {Scheme Variable} %facebook-host-aliases
14198 This variable contains a string for use in @file{/etc/hosts}
14199 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
14200 line contains a entry that maps a known server name of the Facebook
14201 on-line service---e.g., @code{www.facebook.com}---to the local
14202 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
14204 This variable is typically used in the @code{hosts-file} field of an
14205 @code{operating-system} declaration (@pxref{operating-system Reference,
14206 @file{/etc/hosts}}):
14209 (use-modules (gnu) (guix))
14212 (host-name "mymachine")
14215 ;; Create a /etc/hosts file with aliases for "localhost"
14216 ;; and "mymachine", as well as for Facebook servers.
14217 (plain-file "hosts"
14218 (string-append (local-host-aliases host-name)
14219 %facebook-host-aliases))))
14222 This mechanism can prevent programs running locally, such as Web
14223 browsers, from accessing Facebook.
14226 The @code{(gnu services avahi)} provides the following definition.
14228 @defvr {Scheme Variable} avahi-service-type
14229 This is the service that runs @command{avahi-daemon}, a system-wide
14230 mDNS/DNS-SD responder that allows for service discovery and
14231 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
14232 Its value must be a @code{zero-configuration} record---see below.
14234 This service extends the name service cache daemon (nscd) so that it can
14235 resolve @code{.local} host names using
14236 @uref{http://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
14237 Service Switch}, for information on host name resolution.
14239 Additionally, add the @var{avahi} package to the system profile so that
14240 commands such as @command{avahi-browse} are directly usable.
14243 @deftp {Data Type} avahi-configuration
14244 Data type representation the configuration for Avahi.
14248 @item @code{host-name} (default: @code{#f})
14249 If different from @code{#f}, use that as the host name to
14250 publish for this machine; otherwise, use the machine's actual host name.
14252 @item @code{publish?} (default: @code{#t})
14253 When true, allow host names and services to be published (broadcast) over the
14256 @item @code{publish-workstation?} (default: @code{#t})
14257 When true, @command{avahi-daemon} publishes the machine's host name and IP
14258 address via mDNS on the local network. To view the host names published on
14259 your local network, you can run:
14262 avahi-browse _workstation._tcp
14265 @item @code{wide-area?} (default: @code{#f})
14266 When true, DNS-SD over unicast DNS is enabled.
14268 @item @code{ipv4?} (default: @code{#t})
14269 @itemx @code{ipv6?} (default: @code{#t})
14270 These fields determine whether to use IPv4/IPv6 sockets.
14272 @item @code{domains-to-browse} (default: @code{'()})
14273 This is a list of domains to browse.
14277 @deffn {Scheme Variable} openvswitch-service-type
14278 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
14279 service, whose value should be an @code{openvswitch-configuration}
14283 @deftp {Data Type} openvswitch-configuration
14284 Data type representing the configuration of Open vSwitch, a multilayer
14285 virtual switch which is designed to enable massive network automation
14286 through programmatic extension.
14289 @item @code{package} (default: @var{openvswitch})
14290 Package object of the Open vSwitch.
14295 @defvr {Scheme Variable} pagekite-service-type
14296 This is the service type for the @uref{https://pagekite.net, PageKite} service,
14297 a tunneling solution for making localhost servers publicly visible, even from
14298 behind restrictive firewalls or NAT without forwarded ports. The value for
14299 this service type is a @code{pagekite-configuration} record.
14301 Here's an example exposing the local HTTP and SSH daemons:
14304 (service pagekite-service-type
14305 (pagekite-configuration
14306 (kites '("http:@@kitename:localhost:80:@@kitesecret"
14307 "raw/22:@@kitename:localhost:22:@@kitesecret"))
14308 (extra-file "/etc/pagekite.rc")))
14312 @deftp {Data Type} pagekite-configuration
14313 Data type representing the configuration of PageKite.
14316 @item @code{package} (default: @var{pagekite})
14317 Package object of PageKite.
14319 @item @code{kitename} (default: @code{#f})
14320 PageKite name for authenticating to the frontend server.
14322 @item @code{kitesecret} (default: @code{#f})
14323 Shared secret for authenticating to the frontend server. You should probably
14324 put this inside @code{extra-file} instead.
14326 @item @code{frontend} (default: @code{#f})
14327 Connect to the named PageKite frontend server instead of the
14328 @uref{https://pagekite.net,,pagekite.net} service.
14330 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
14331 List of service kites to use. Exposes HTTP on port 80 by default. The format
14332 is @code{proto:kitename:host:port:secret}.
14334 @item @code{extra-file} (default: @code{#f})
14335 Extra configuration file to read, which you are expected to create manually.
14336 Use this to add additional options and manage shared secrets out-of-band.
14342 @subsection X Window
14345 @cindex X Window System
14346 @cindex login manager
14347 Support for the X Window graphical display system---specifically
14348 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
14349 there is no @code{xorg-service} procedure. Instead, the X server is
14350 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
14353 @cindex GNOME, login manager
14354 GDM of course allows users to log in into window managers and desktop
14355 environments other than GNOME; for those using GNOME, GDM is required for
14356 features such as automatic screen locking.
14358 @cindex window manager
14359 To use X11, you must install at least one @dfn{window manager}---for
14360 example the @code{windowmaker} or @code{openbox} packages---preferably
14361 by adding it to the @code{packages} field of your operating system
14362 definition (@pxref{operating-system Reference, system-wide packages}).
14364 @defvr {Scheme Variable} gdm-service-type
14365 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
14366 Desktop Manager} (GDM), a program that manages graphical display servers and
14367 handles graphical user logins. Its value must be a @code{gdm-configuration}
14370 @cindex session types (X11)
14371 @cindex X11 session types
14372 GDM looks for @dfn{session types} described by the @file{.desktop} files in
14373 @file{/run/current-system/profile/share/xsessions} and allows users to choose
14374 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
14375 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
14376 set of packages automatically makes them available at the log-in screen.
14378 In addition, @file{~/.xsession} files are honored. When available,
14379 @file{~/.xsession} must be an executable that starts a window manager
14380 and/or other X clients.
14383 @deftp {Data Type} gdm-configuration
14385 @item @code{auto-login?} (default: @code{#f})
14386 @itemx @code{default-user} (default: @code{#f})
14387 When @code{auto-login?} is false, GDM presents a log-in screen.
14389 When @code{auto-login?} is true, GDM logs in directly as
14390 @code{default-user}.
14392 @item @code{debug?} (default: @code{#f})
14393 When true, GDM writes debug messages to its log.
14395 @item @code{gnome-shell-assets} (default: ...)
14396 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
14398 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
14399 Configuration of the Xorg graphical server.
14401 @item @code{xsession} (default: @code{(xinitrc)})
14402 Script to run before starting a X session.
14404 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
14405 File name of the @code{dbus-daemon} executable.
14407 @item @code{gdm} (default: @code{gdm})
14408 The GDM package to use.
14412 @defvr {Scheme Variable} slim-service-type
14413 This is the type for the SLiM graphical login manager for X11.
14415 Like GDM, SLiM looks for session types described by @file{.desktop} files and
14416 allows users to choose a session from the log-in screen using @kbd{F1}. It
14417 also honors @file{~/.xsession} files.
14419 Unlike GDM, SLiM does not spawn the user session on a different VT after
14420 logging in, which means that you can only start one graphical session. If you
14421 want to be able to run multiple graphical sessions at the same time you have
14422 to add multiple SLiM services to your system services. The following example
14423 shows how to replace the default GDM service with two SLiM services on tty7
14427 (use-modules (gnu services)
14428 (gnu services desktop)
14429 (gnu services xorg)
14430 (srfi srfi-1)) ;for 'remove'
14434 (services (cons* (service slim-service-type (slim-configuration
14437 (service slim-service-type (slim-configuration
14440 (remove (lambda (service)
14441 (eq? (service-kind service) gdm-service-type))
14442 %desktop-services))))
14447 @deftp {Data Type} slim-configuration
14448 Data type representing the configuration of @code{slim-service-type}.
14451 @item @code{allow-empty-passwords?} (default: @code{#t})
14452 Whether to allow logins with empty passwords.
14454 @item @code{auto-login?} (default: @code{#f})
14455 @itemx @code{default-user} (default: @code{""})
14456 When @code{auto-login?} is false, SLiM presents a log-in screen.
14458 When @code{auto-login?} is true, SLiM logs in directly as
14459 @code{default-user}.
14461 @item @code{theme} (default: @code{%default-slim-theme})
14462 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
14463 The graphical theme to use and its name.
14465 @item @code{auto-login-session} (default: @code{#f})
14466 If true, this must be the name of the executable to start as the default
14467 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
14469 If false, a session described by one of the available @file{.desktop}
14470 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
14474 You must install at least one window manager in the system profile or in
14475 your user profile. Failing to do that, if @code{auto-login-session} is
14476 false, you will be unable to log in.
14479 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14480 Configuration of the Xorg graphical server.
14482 @item @code{display} (default @code{":0"})
14483 The display on which to start the Xorg graphical server.
14485 @item @code{vt} (default @code{"vt7"})
14486 The VT on which to start the Xorg graphical server.
14488 @item @code{xauth} (default: @code{xauth})
14489 The XAuth package to use.
14491 @item @code{shepherd} (default: @code{shepherd})
14492 The Shepherd package used when invoking @command{halt} and
14495 @item @code{sessreg} (default: @code{sessreg})
14496 The sessreg package used in order to register the session.
14498 @item @code{slim} (default: @code{slim})
14499 The SLiM package to use.
14503 @defvr {Scheme Variable} %default-theme
14504 @defvrx {Scheme Variable} %default-theme-name
14505 The default SLiM theme and its name.
14509 @deftp {Data Type} sddm-configuration
14510 This is the data type representing the sddm service configuration.
14513 @item @code{display-server} (default: "x11")
14514 Select display server to use for the greeter. Valid values are "x11"
14517 @item @code{numlock} (default: "on")
14518 Valid values are "on", "off" or "none".
14520 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
14521 Command to run when halting.
14523 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
14524 Command to run when rebooting.
14526 @item @code{theme} (default "maldives")
14527 Theme to use. Default themes provided by SDDM are "elarun", "maldives" or "maya".
14529 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
14530 Directory to look for themes.
14532 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
14533 Directory to look for faces.
14535 @item @code{default-path} (default "/run/current-system/profile/bin")
14536 Default PATH to use.
14538 @item @code{minimum-uid} (default: 1000)
14539 Minimum UID displayed in SDDM and allowed for log-in.
14541 @item @code{maximum-uid} (default: 2000)
14542 Maximum UID to display in SDDM.
14544 @item @code{remember-last-user?} (default #t)
14545 Remember last user.
14547 @item @code{remember-last-session?} (default #t)
14548 Remember last session.
14550 @item @code{hide-users} (default "")
14551 Usernames to hide from SDDM greeter.
14553 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
14554 Users with shells listed will be hidden from the SDDM greeter.
14556 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
14557 Script to run before starting a wayland session.
14559 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
14560 Directory to look for desktop files starting wayland sessions.
14562 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14563 Configuration of the Xorg graphical server.
14565 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
14568 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
14571 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
14572 Script to run after starting xorg-server.
14574 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
14575 Script to run before stopping xorg-server.
14577 @item @code{xsession-command} (default: @code{xinitrc})
14578 Script to run before starting a X session.
14580 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
14581 Directory to look for desktop files starting X sessions.
14583 @item @code{minimum-vt} (default: 7)
14586 @item @code{auto-login-user} (default "")
14587 User to use for auto-login.
14589 @item @code{auto-login-session} (default "")
14590 Desktop file to use for auto-login.
14592 @item @code{relogin?} (default #f)
14593 Relogin after logout.
14598 @cindex login manager
14600 @defvr {Scheme Variable} sddm-service-type
14601 This is the type of the service to run the
14602 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
14603 must be a @code{sddm-configuration} record (see below).
14605 Here's an example use:
14608 (service sddm-service-type
14609 (sddm-configuration
14610 (auto-login-user "alice")
14611 (auto-login-session "xfce.desktop")))
14615 @deftp {Data Type} sddm-configuration
14616 This data type represents the configuration of the SDDM login manager.
14617 The available fields are:
14620 @item @code{sddm} (default: @code{sddm})
14621 The SDDM package to use.
14623 @item @code{display-server} (default: @code{"x11"})
14624 This must be either @code{"x11"} or @code{"wayland"}.
14626 @c FIXME: Add more fields.
14628 @item @code{auto-login-user} (default: @code{""})
14629 If non-empty, this is the user account under which to log in
14632 @item @code{auto-login-session} (default: @code{""})
14633 If non-empty, this is the @file{.desktop} file name to use as the
14634 auto-login session.
14638 @cindex Xorg, configuration
14639 @deftp {Data Type} xorg-configuration
14640 This data type represents the configuration of the Xorg graphical display
14641 server. Note that there is not Xorg service; instead, the X server is started
14642 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
14643 of these display managers aggregates an @code{xorg-configuration} record.
14646 @item @code{modules} (default: @code{%default-xorg-modules})
14647 This is a list of @dfn{module packages} loaded by the Xorg
14648 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
14650 @item @code{fonts} (default: @code{%default-xorg-fonts})
14651 This is a list of font directories to add to the server's @dfn{font path}.
14653 @item @code{drivers} (default: @code{'()})
14654 This must be either the empty list, in which case Xorg chooses a graphics
14655 driver automatically, or a list of driver names that will be tried in this
14656 order---e.g., @code{("modesetting" "vesa")}.
14658 @item @code{resolutions} (default: @code{'()})
14659 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
14660 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
14663 @cindex keyboard layout, for Xorg
14664 @cindex keymap, for Xorg
14665 @item @code{keyboard-layout} (default: @code{#f})
14666 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
14667 English (``qwerty'') for a 105-key PC keyboard.
14669 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
14670 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
14671 information on how to specify the keyboard layout.
14673 @item @code{extra-config} (default: @code{'()})
14674 This is a list of strings or objects appended to the configuration file. It
14675 is used to pass extra text to be added verbatim to the configuration file.
14677 @item @code{server} (default: @code{xorg-server})
14678 This is the package providing the Xorg server.
14680 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
14681 This is the list of command-line arguments to pass to the X server. The
14682 default is @code{-nolisten tcp}.
14686 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
14687 [@var{login-manager-service-type}]
14688 Tell the log-in manager (of type @var{login-manager-service-type}) to use
14689 @var{config}, an @code{<xorg-configuration>} record.
14691 Since the Xorg configuration is embedded in the log-in manager's
14692 configuration---e.g., @code{gdm-configuration}---this procedure provides a
14693 shorthand to set the Xorg configuration.
14696 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
14697 Return a @code{startx} script in which the modules, fonts, etc. specified
14698 in @var{config}, are available. The result should be used in place of
14701 Usually the X server is started by a login manager.
14705 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
14706 Add @var{package}, a package for a screen locker or screen saver whose
14707 command is @var{program}, to the set of setuid programs and add a PAM entry
14708 for it. For example:
14711 (screen-locker-service xlockmore "xlock")
14714 makes the good ol' XlockMore usable.
14718 @node Printing Services
14719 @subsection Printing Services
14721 @cindex printer support with CUPS
14722 The @code{(gnu services cups)} module provides a Guix service definition
14723 for the CUPS printing service. To add printer support to a Guix
14724 system, add a @code{cups-service} to the operating system definition:
14726 @deffn {Scheme Variable} cups-service-type
14727 The service type for the CUPS print server. Its value should be a valid
14728 CUPS configuration (see below). To use the default settings, simply
14731 (service cups-service-type)
14735 The CUPS configuration controls the basic things about your CUPS
14736 installation: what interfaces it listens on, what to do if a print job
14737 fails, how much logging to do, and so on. To actually add a printer,
14738 you have to visit the @url{http://localhost:631} URL, or use a tool such
14739 as GNOME's printer configuration services. By default, configuring a
14740 CUPS service will generate a self-signed certificate if needed, for
14741 secure connections to the print server.
14743 Suppose you want to enable the Web interface of CUPS and also add
14744 support for Epson printers @i{via} the @code{escpr} package and for HP
14745 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
14746 like this (you need to use the @code{(gnu packages cups)} module):
14749 (service cups-service-type
14750 (cups-configuration
14751 (web-interface? #t)
14753 (list cups-filters escpr hplip-minimal))))
14756 Note: If you wish to use the Qt5 based GUI which comes with the hplip
14757 package then it is suggested that you install the @code{hplip} package,
14758 either in your OS configuration file or as your user.
14760 The available configuration parameters follow. Each parameter
14761 definition is preceded by its type; for example, @samp{string-list foo}
14762 indicates that the @code{foo} parameter should be specified as a list of
14763 strings. There is also a way to specify the configuration as a string,
14764 if you have an old @code{cupsd.conf} file that you want to port over
14765 from some other system; see the end for more details.
14767 @c The following documentation was initially generated by
14768 @c (generate-documentation) in (gnu services cups). Manually maintained
14769 @c documentation is better, so we shouldn't hesitate to edit below as
14770 @c needed. However if the change you want to make to this documentation
14771 @c can be done in an automated way, it's probably easier to change
14772 @c (generate-documentation) than to make it below and have to deal with
14773 @c the churn as CUPS updates.
14776 Available @code{cups-configuration} fields are:
14778 @deftypevr {@code{cups-configuration} parameter} package cups
14782 @deftypevr {@code{cups-configuration} parameter} package-list extensions
14783 Drivers and other extensions to the CUPS package.
14786 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
14787 Configuration of where to write logs, what directories to use for print
14788 spools, and related privileged configuration parameters.
14790 Available @code{files-configuration} fields are:
14792 @deftypevr {@code{files-configuration} parameter} log-location access-log
14793 Defines the access log filename. Specifying a blank filename disables
14794 access log generation. The value @code{stderr} causes log entries to be
14795 sent to the standard error file when the scheduler is running in the
14796 foreground, or to the system log daemon when run in the background. The
14797 value @code{syslog} causes log entries to be sent to the system log
14798 daemon. The server name may be included in filenames using the string
14799 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
14801 Defaults to @samp{"/var/log/cups/access_log"}.
14804 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
14805 Where CUPS should cache data.
14807 Defaults to @samp{"/var/cache/cups"}.
14810 @deftypevr {@code{files-configuration} parameter} string config-file-perm
14811 Specifies the permissions for all configuration files that the scheduler
14814 Note that the permissions for the printers.conf file are currently
14815 masked to only allow access from the scheduler user (typically root).
14816 This is done because printer device URIs sometimes contain sensitive
14817 authentication information that should not be generally known on the
14818 system. There is no way to disable this security feature.
14820 Defaults to @samp{"0640"}.
14823 @deftypevr {@code{files-configuration} parameter} log-location error-log
14824 Defines the error log filename. Specifying a blank filename disables
14825 error log generation. The value @code{stderr} causes log entries to be
14826 sent to the standard error file when the scheduler is running in the
14827 foreground, or to the system log daemon when run in the background. The
14828 value @code{syslog} causes log entries to be sent to the system log
14829 daemon. The server name may be included in filenames using the string
14830 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
14832 Defaults to @samp{"/var/log/cups/error_log"}.
14835 @deftypevr {@code{files-configuration} parameter} string fatal-errors
14836 Specifies which errors are fatal, causing the scheduler to exit. The
14841 No errors are fatal.
14844 All of the errors below are fatal.
14847 Browsing initialization errors are fatal, for example failed connections
14848 to the DNS-SD daemon.
14851 Configuration file syntax errors are fatal.
14854 Listen or Port errors are fatal, except for IPv6 failures on the
14855 loopback or @code{any} addresses.
14858 Log file creation or write errors are fatal.
14861 Bad startup file permissions are fatal, for example shared TLS
14862 certificate and key files with world-read permissions.
14865 Defaults to @samp{"all -browse"}.
14868 @deftypevr {@code{files-configuration} parameter} boolean file-device?
14869 Specifies whether the file pseudo-device can be used for new printer
14870 queues. The URI @uref{file:///dev/null} is always allowed.
14872 Defaults to @samp{#f}.
14875 @deftypevr {@code{files-configuration} parameter} string group
14876 Specifies the group name or ID that will be used when executing external
14879 Defaults to @samp{"lp"}.
14882 @deftypevr {@code{files-configuration} parameter} string log-file-perm
14883 Specifies the permissions for all log files that the scheduler writes.
14885 Defaults to @samp{"0644"}.
14888 @deftypevr {@code{files-configuration} parameter} log-location page-log
14889 Defines the page log filename. Specifying a blank filename disables
14890 page log generation. The value @code{stderr} causes log entries to be
14891 sent to the standard error file when the scheduler is running in the
14892 foreground, or to the system log daemon when run in the background. The
14893 value @code{syslog} causes log entries to be sent to the system log
14894 daemon. The server name may be included in filenames using the string
14895 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
14897 Defaults to @samp{"/var/log/cups/page_log"}.
14900 @deftypevr {@code{files-configuration} parameter} string remote-root
14901 Specifies the username that is associated with unauthenticated accesses
14902 by clients claiming to be the root user. The default is @code{remroot}.
14904 Defaults to @samp{"remroot"}.
14907 @deftypevr {@code{files-configuration} parameter} file-name request-root
14908 Specifies the directory that contains print jobs and other HTTP request
14911 Defaults to @samp{"/var/spool/cups"}.
14914 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
14915 Specifies the level of security sandboxing that is applied to print
14916 filters, backends, and other child processes of the scheduler; either
14917 @code{relaxed} or @code{strict}. This directive is currently only
14918 used/supported on macOS.
14920 Defaults to @samp{strict}.
14923 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
14924 Specifies the location of TLS certificates and private keys. CUPS will
14925 look for public and private keys in this directory: a @code{.crt} files
14926 for PEM-encoded certificates and corresponding @code{.key} files for
14927 PEM-encoded private keys.
14929 Defaults to @samp{"/etc/cups/ssl"}.
14932 @deftypevr {@code{files-configuration} parameter} file-name server-root
14933 Specifies the directory containing the server configuration files.
14935 Defaults to @samp{"/etc/cups"}.
14938 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
14939 Specifies whether the scheduler calls fsync(2) after writing
14940 configuration or state files.
14942 Defaults to @samp{#f}.
14945 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
14946 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
14949 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
14950 Specifies the directory where temporary files are stored.
14952 Defaults to @samp{"/var/spool/cups/tmp"}.
14955 @deftypevr {@code{files-configuration} parameter} string user
14956 Specifies the user name or ID that is used when running external
14959 Defaults to @samp{"lp"}.
14962 @deftypevr {@code{files-configuration} parameter} string set-env
14963 Set the specified environment variable to be passed to child processes.
14965 Defaults to @samp{"variable value"}.
14969 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
14970 Specifies the logging level for the AccessLog file. The @code{config}
14971 level logs when printers and classes are added, deleted, or modified and
14972 when configuration files are accessed or updated. The @code{actions}
14973 level logs when print jobs are submitted, held, released, modified, or
14974 canceled, and any of the conditions for @code{config}. The @code{all}
14975 level logs all requests.
14977 Defaults to @samp{actions}.
14980 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
14981 Specifies whether to purge job history data automatically when it is no
14982 longer required for quotas.
14984 Defaults to @samp{#f}.
14987 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
14988 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
14989 For example, @samp{"_cups" "_print"} will tell network clients that both
14990 CUPS sharing and IPP Everywhere are supported.
14992 Defaults to @samp{"_cups"}.
14995 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
14996 Specifies which protocols to use for local printer sharing.
14998 Defaults to @samp{dnssd}.
15001 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
15002 Specifies whether the CUPS web interface is advertised.
15004 Defaults to @samp{#f}.
15007 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
15008 Specifies whether shared printers are advertised.
15010 Defaults to @samp{#f}.
15013 @deftypevr {@code{cups-configuration} parameter} string classification
15014 Specifies the security classification of the server. Any valid banner
15015 name can be used, including "classified", "confidential", "secret",
15016 "topsecret", and "unclassified", or the banner can be omitted to disable
15017 secure printing functions.
15019 Defaults to @samp{""}.
15022 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
15023 Specifies whether users may override the classification (cover page) of
15024 individual print jobs using the @code{job-sheets} option.
15026 Defaults to @samp{#f}.
15029 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
15030 Specifies the default type of authentication to use.
15032 Defaults to @samp{Basic}.
15035 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
15036 Specifies whether encryption will be used for authenticated requests.
15038 Defaults to @samp{Required}.
15041 @deftypevr {@code{cups-configuration} parameter} string default-language
15042 Specifies the default language to use for text and web content.
15044 Defaults to @samp{"en"}.
15047 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
15048 Specifies the default paper size for new print queues. @samp{"Auto"}
15049 uses a locale-specific default, while @samp{"None"} specifies there is
15050 no default paper size. Specific size names are typically
15051 @samp{"Letter"} or @samp{"A4"}.
15053 Defaults to @samp{"Auto"}.
15056 @deftypevr {@code{cups-configuration} parameter} string default-policy
15057 Specifies the default access policy to use.
15059 Defaults to @samp{"default"}.
15062 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
15063 Specifies whether local printers are shared by default.
15065 Defaults to @samp{#t}.
15068 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
15069 Specifies the delay for updating of configuration and state files, in
15070 seconds. A value of 0 causes the update to happen as soon as possible,
15071 typically within a few milliseconds.
15073 Defaults to @samp{30}.
15076 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
15077 Specifies what to do when an error occurs. Possible values are
15078 @code{abort-job}, which will discard the failed print job;
15079 @code{retry-job}, which will retry the job at a later time;
15080 @code{retry-current-job}, which retries the failed job immediately; and
15081 @code{stop-printer}, which stops the printer.
15083 Defaults to @samp{stop-printer}.
15086 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
15087 Specifies the maximum cost of filters that are run concurrently, which
15088 can be used to minimize disk, memory, and CPU resource problems. A
15089 limit of 0 disables filter limiting. An average print to a
15090 non-PostScript printer needs a filter limit of about 200. A PostScript
15091 printer needs about half that (100). Setting the limit below these
15092 thresholds will effectively limit the scheduler to printing a single job
15095 Defaults to @samp{0}.
15098 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
15099 Specifies the scheduling priority of filters that are run to print a
15100 job. The nice value ranges from 0, the highest priority, to 19, the
15103 Defaults to @samp{0}.
15106 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
15107 Specifies whether to do reverse lookups on connecting clients. The
15108 @code{double} setting causes @code{cupsd} to verify that the hostname
15109 resolved from the address matches one of the addresses returned for that
15110 hostname. Double lookups also prevent clients with unregistered
15111 addresses from connecting to your server. Only set this option to
15112 @code{#t} or @code{double} if absolutely required.
15114 Defaults to @samp{#f}.
15117 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
15118 Specifies the number of seconds to wait before killing the filters and
15119 backend associated with a canceled or held job.
15121 Defaults to @samp{30}.
15124 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
15125 Specifies the interval between retries of jobs in seconds. This is
15126 typically used for fax queues but can also be used with normal print
15127 queues whose error policy is @code{retry-job} or
15128 @code{retry-current-job}.
15130 Defaults to @samp{30}.
15133 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
15134 Specifies the number of retries that are done for jobs. This is
15135 typically used for fax queues but can also be used with normal print
15136 queues whose error policy is @code{retry-job} or
15137 @code{retry-current-job}.
15139 Defaults to @samp{5}.
15142 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
15143 Specifies whether to support HTTP keep-alive connections.
15145 Defaults to @samp{#t}.
15148 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
15149 Specifies how long an idle client connection remains open, in seconds.
15151 Defaults to @samp{30}.
15154 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
15155 Specifies the maximum size of print files, IPP requests, and HTML form
15156 data. A limit of 0 disables the limit check.
15158 Defaults to @samp{0}.
15161 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
15162 Listens on the specified interfaces for connections. Valid values are
15163 of the form @var{address}:@var{port}, where @var{address} is either an
15164 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
15165 indicate all addresses. Values can also be file names of local UNIX
15166 domain sockets. The Listen directive is similar to the Port directive
15167 but allows you to restrict access to specific interfaces or networks.
15170 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
15171 Specifies the number of pending connections that will be allowed. This
15172 normally only affects very busy servers that have reached the MaxClients
15173 limit, but can also be triggered by large numbers of simultaneous
15174 connections. When the limit is reached, the operating system will
15175 refuse additional connections until the scheduler can accept the pending
15178 Defaults to @samp{128}.
15181 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
15182 Specifies a set of additional access controls.
15184 Available @code{location-access-controls} fields are:
15186 @deftypevr {@code{location-access-controls} parameter} file-name path
15187 Specifies the URI path to which the access control applies.
15190 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
15191 Access controls for all access to this path, in the same format as the
15192 @code{access-controls} of @code{operation-access-control}.
15194 Defaults to @samp{()}.
15197 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
15198 Access controls for method-specific access to this path.
15200 Defaults to @samp{()}.
15202 Available @code{method-access-controls} fields are:
15204 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
15205 If @code{#t}, apply access controls to all methods except the listed
15206 methods. Otherwise apply to only the listed methods.
15208 Defaults to @samp{#f}.
15211 @deftypevr {@code{method-access-controls} parameter} method-list methods
15212 Methods to which this access control applies.
15214 Defaults to @samp{()}.
15217 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
15218 Access control directives, as a list of strings. Each string should be
15219 one directive, such as "Order allow,deny".
15221 Defaults to @samp{()}.
15226 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
15227 Specifies the number of debugging messages that are retained for logging
15228 if an error occurs in a print job. Debug messages are logged regardless
15229 of the LogLevel setting.
15231 Defaults to @samp{100}.
15234 @deftypevr {@code{cups-configuration} parameter} log-level log-level
15235 Specifies the level of logging for the ErrorLog file. The value
15236 @code{none} stops all logging while @code{debug2} logs everything.
15238 Defaults to @samp{info}.
15241 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
15242 Specifies the format of the date and time in the log files. The value
15243 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
15245 Defaults to @samp{standard}.
15248 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
15249 Specifies the maximum number of simultaneous clients that are allowed by
15252 Defaults to @samp{100}.
15255 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
15256 Specifies the maximum number of simultaneous clients that are allowed
15257 from a single address.
15259 Defaults to @samp{100}.
15262 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
15263 Specifies the maximum number of copies that a user can print of each
15266 Defaults to @samp{9999}.
15269 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
15270 Specifies the maximum time a job may remain in the @code{indefinite}
15271 hold state before it is canceled. A value of 0 disables cancellation of
15274 Defaults to @samp{0}.
15277 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
15278 Specifies the maximum number of simultaneous jobs that are allowed. Set
15279 to 0 to allow an unlimited number of jobs.
15281 Defaults to @samp{500}.
15284 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
15285 Specifies the maximum number of simultaneous jobs that are allowed per
15286 printer. A value of 0 allows up to MaxJobs jobs per printer.
15288 Defaults to @samp{0}.
15291 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
15292 Specifies the maximum number of simultaneous jobs that are allowed per
15293 user. A value of 0 allows up to MaxJobs jobs per user.
15295 Defaults to @samp{0}.
15298 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
15299 Specifies the maximum time a job may take to print before it is
15300 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
15302 Defaults to @samp{10800}.
15305 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
15306 Specifies the maximum size of the log files before they are rotated, in
15307 bytes. The value 0 disables log rotation.
15309 Defaults to @samp{1048576}.
15312 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
15313 Specifies the maximum amount of time to allow between files in a
15314 multiple file print job, in seconds.
15316 Defaults to @samp{300}.
15319 @deftypevr {@code{cups-configuration} parameter} string page-log-format
15320 Specifies the format of PageLog lines. Sequences beginning with percent
15321 (@samp{%}) characters are replaced with the corresponding information,
15322 while all other characters are copied literally. The following percent
15323 sequences are recognized:
15327 insert a single percent character
15330 insert the value of the specified IPP attribute
15333 insert the number of copies for the current page
15336 insert the current page number
15339 insert the current date and time in common log format
15345 insert the printer name
15348 insert the username
15351 A value of the empty string disables page logging. The string @code{%p
15352 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
15353 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
15356 Defaults to @samp{""}.
15359 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
15360 Passes the specified environment variable(s) to child processes; a list
15363 Defaults to @samp{()}.
15366 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
15367 Specifies named access control policies.
15369 Available @code{policy-configuration} fields are:
15371 @deftypevr {@code{policy-configuration} parameter} string name
15372 Name of the policy.
15375 @deftypevr {@code{policy-configuration} parameter} string job-private-access
15376 Specifies an access list for a job's private values. @code{@@ACL} maps
15377 to the printer's requesting-user-name-allowed or
15378 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15379 owner. @code{@@SYSTEM} maps to the groups listed for the
15380 @code{system-group} field of the @code{files-config} configuration,
15381 which is reified into the @code{cups-files.conf(5)} file. Other
15382 possible elements of the access list include specific user names, and
15383 @code{@@@var{group}} to indicate members of a specific group. The
15384 access list may also be simply @code{all} or @code{default}.
15386 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15389 @deftypevr {@code{policy-configuration} parameter} string job-private-values
15390 Specifies the list of job values to make private, or @code{all},
15391 @code{default}, or @code{none}.
15393 Defaults to @samp{"job-name job-originating-host-name
15394 job-originating-user-name phone"}.
15397 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
15398 Specifies an access list for a subscription's private values.
15399 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
15400 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15401 owner. @code{@@SYSTEM} maps to the groups listed for the
15402 @code{system-group} field of the @code{files-config} configuration,
15403 which is reified into the @code{cups-files.conf(5)} file. Other
15404 possible elements of the access list include specific user names, and
15405 @code{@@@var{group}} to indicate members of a specific group. The
15406 access list may also be simply @code{all} or @code{default}.
15408 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15411 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
15412 Specifies the list of job values to make private, or @code{all},
15413 @code{default}, or @code{none}.
15415 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
15416 notify-subscriber-user-name notify-user-data"}.
15419 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
15420 Access control by IPP operation.
15422 Defaults to @samp{()}.
15426 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
15427 Specifies whether job files (documents) are preserved after a job is
15428 printed. If a numeric value is specified, job files are preserved for
15429 the indicated number of seconds after printing. Otherwise a boolean
15430 value applies indefinitely.
15432 Defaults to @samp{86400}.
15435 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
15436 Specifies whether the job history is preserved after a job is printed.
15437 If a numeric value is specified, the job history is preserved for the
15438 indicated number of seconds after printing. If @code{#t}, the job
15439 history is preserved until the MaxJobs limit is reached.
15441 Defaults to @samp{#t}.
15444 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
15445 Specifies the amount of time to wait for job completion before
15446 restarting the scheduler.
15448 Defaults to @samp{30}.
15451 @deftypevr {@code{cups-configuration} parameter} string rip-cache
15452 Specifies the maximum amount of memory to use when converting documents
15453 into bitmaps for a printer.
15455 Defaults to @samp{"128m"}.
15458 @deftypevr {@code{cups-configuration} parameter} string server-admin
15459 Specifies the email address of the server administrator.
15461 Defaults to @samp{"root@@localhost.localdomain"}.
15464 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
15465 The ServerAlias directive is used for HTTP Host header validation when
15466 clients connect to the scheduler from external interfaces. Using the
15467 special name @code{*} can expose your system to known browser-based DNS
15468 rebinding attacks, even when accessing sites through a firewall. If the
15469 auto-discovery of alternate names does not work, we recommend listing
15470 each alternate name with a ServerAlias directive instead of using
15473 Defaults to @samp{*}.
15476 @deftypevr {@code{cups-configuration} parameter} string server-name
15477 Specifies the fully-qualified host name of the server.
15479 Defaults to @samp{"localhost"}.
15482 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
15483 Specifies what information is included in the Server header of HTTP
15484 responses. @code{None} disables the Server header. @code{ProductOnly}
15485 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
15486 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
15487 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
15488 the output of the @code{uname} command. @code{Full} reports @code{CUPS
15489 2.0.0 (@var{uname}) IPP/2.0}.
15491 Defaults to @samp{Minimal}.
15494 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
15495 Listens on the specified interfaces for encrypted connections. Valid
15496 values are of the form @var{address}:@var{port}, where @var{address} is
15497 either an IPv6 address enclosed in brackets, an IPv4 address, or
15498 @code{*} to indicate all addresses.
15500 Defaults to @samp{()}.
15503 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
15504 Sets encryption options. By default, CUPS only supports encryption
15505 using TLS v1.0 or higher using known secure cipher suites. Security is
15506 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
15507 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
15508 suites, which are required for some older clients. The @code{AllowSSL3} option
15509 enables SSL v3.0, which is required for some older clients that do not support
15510 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
15511 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
15512 protocol version to TLS v1.1.
15514 Defaults to @samp{()}.
15517 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
15518 Specifies whether the scheduler requires clients to strictly adhere to
15519 the IPP specifications.
15521 Defaults to @samp{#f}.
15524 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
15525 Specifies the HTTP request timeout, in seconds.
15527 Defaults to @samp{300}.
15531 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
15532 Specifies whether the web interface is enabled.
15534 Defaults to @samp{#f}.
15537 At this point you're probably thinking ``oh dear, Guix manual, I like
15538 you but you can stop already with the configuration options''. Indeed.
15539 However, one more point: it could be that you have an existing
15540 @code{cupsd.conf} that you want to use. In that case, you can pass an
15541 @code{opaque-cups-configuration} as the configuration of a
15542 @code{cups-service-type}.
15544 Available @code{opaque-cups-configuration} fields are:
15546 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
15550 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
15551 The contents of the @code{cupsd.conf}, as a string.
15554 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
15555 The contents of the @code{cups-files.conf} file, as a string.
15558 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
15559 strings of the same name, you could instantiate a CUPS service like
15563 (service cups-service-type
15564 (opaque-cups-configuration
15565 (cupsd.conf cupsd.conf)
15566 (cups-files.conf cups-files.conf)))
15570 @node Desktop Services
15571 @subsection Desktop Services
15573 The @code{(gnu services desktop)} module provides services that are
15574 usually useful in the context of a ``desktop'' setup---that is, on a
15575 machine running a graphical display server, possibly with graphical user
15576 interfaces, etc. It also defines services that provide specific desktop
15577 environments like GNOME, Xfce or MATE.
15579 To simplify things, the module defines a variable containing the set of
15580 services that users typically expect on a machine with a graphical
15581 environment and networking:
15583 @defvr {Scheme Variable} %desktop-services
15584 This is a list of services that builds upon @code{%base-services} and
15585 adds or adjusts services for a typical ``desktop'' setup.
15587 In particular, it adds a graphical login manager (@pxref{X Window,
15588 @code{gdm-service-type}}), screen lockers, a network management tool
15589 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
15590 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
15591 energy and color management services, the @code{elogind} login and seat
15592 manager, the Polkit privilege service, the GeoClue location service, the
15593 AccountsService daemon that allows authorized users change system passwords,
15594 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
15595 name service switch service configured to be able to use @code{nss-mdns}
15596 (@pxref{Name Service Switch, mDNS}).
15599 The @code{%desktop-services} variable can be used as the @code{services}
15600 field of an @code{operating-system} declaration (@pxref{operating-system
15601 Reference, @code{services}}).
15603 Additionally, the @code{gnome-desktop-service-type},
15604 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
15605 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
15606 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
15607 services like the backlight adjustment helpers and the power management
15608 utilities are added to the system, extending @code{polkit} and @code{dbus}
15609 appropriately, allowing GNOME to operate with elevated privileges on a
15610 limited number of special-purpose system interfaces. Additionally,
15611 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
15612 metapackage to the system profile. Likewise, adding the Xfce service
15613 not only adds the @code{xfce} metapackage to the system profile, but it
15614 also gives the Thunar file manager the ability to open a ``root-mode''
15615 file management window, if the user authenticates using the
15616 administrator's password via the standard polkit graphical interface.
15617 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
15618 appropriately, allowing MATE to operate with elevated privileges on a
15619 limited number of special-purpose system interfaces. Additionally,
15620 adding a service of type @code{mate-desktop-service-type} adds the MATE
15621 metapackage to the system profile. ``Adding Enlightenment'' means that
15622 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
15623 are set as setuid, allowing Enlightenment's screen locker and other
15624 functionality to work as expetected.
15626 The desktop environments in Guix use the Xorg display server by
15627 default. If you'd like to use the newer display server protocol
15628 called Wayland, you need to use the @code{sddm-service} instead of
15629 GDM as the graphical login manager. You should then
15630 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
15631 also try starting GNOME on Wayland manually from a TTY with the
15632 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
15633 gnome-session``. Currently only GNOME has support for Wayland.
15635 @defvr {Scheme Variable} gnome-desktop-service-type
15636 This is the type of the service that adds the @uref{https://www.gnome.org,
15637 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
15638 object (see below.)
15640 This service adds the @code{gnome} package to the system profile, and extends
15641 polkit with the actions from @code{gnome-settings-daemon}.
15644 @deftp {Data Type} gnome-desktop-configuration
15645 Configuration record for the GNOME desktop environment.
15648 @item @code{gnome} (default: @code{gnome})
15649 The GNOME package to use.
15653 @defvr {Scheme Variable} xfce-desktop-service-type
15654 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
15655 desktop environment. Its value is an @code{xfce-desktop-configuration} object
15658 This service adds the @code{xfce} package to the system profile, and
15659 extends polkit with the ability for @code{thunar} to manipulate the file
15660 system as root from within a user session, after the user has authenticated
15661 with the administrator's password.
15664 @deftp {Data Type} xfce-desktop-configuration
15665 Configuration record for the Xfce desktop environment.
15668 @item @code{xfce} (default: @code{xfce})
15669 The Xfce package to use.
15673 @deffn {Scheme Variable} mate-desktop-service-type
15674 This is the type of the service that runs the @uref{https://mate-desktop.org/,
15675 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
15676 object (see below.)
15678 This service adds the @code{mate} package to the system
15679 profile, and extends polkit with the actions from
15680 @code{mate-settings-daemon}.
15683 @deftp {Data Type} mate-desktop-configuration
15684 Configuration record for the MATE desktop environment.
15687 @item @code{mate} (default: @code{mate})
15688 The MATE package to use.
15692 @deffn {Scheme Variable} enlightenment-desktop-service-type
15693 Return a service that adds the @code{enlightenment} package to the system
15694 profile, and extends dbus with actions from @code{efl}.
15697 @deftp {Data Type} enlightenment-desktop-service-configuration
15699 @item @code{enlightenment} (default: @code{enlightenment})
15700 The enlightenment package to use.
15704 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
15705 the default @code{%desktop-services} variable doesn't include any of
15706 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
15707 @code{%desktop-services} in the @code{services} field of your
15708 @code{operating-system}:
15711 (use-modules (gnu))
15712 (use-service-modules desktop)
15715 ;; cons* adds items to the list given as its last argument.
15716 (services (cons* (service gnome-desktop-service-type)
15717 (service xfce-desktop-service)
15718 %desktop-services))
15722 These desktop environments will then be available as options in the
15723 graphical login window.
15725 The actual service definitions included in @code{%desktop-services} and
15726 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
15727 are described below.
15729 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
15730 Return a service that runs the ``system bus'', using @var{dbus}, with
15731 support for @var{services}.
15733 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
15734 facility. Its system bus is used to allow system services to communicate
15735 and to be notified of system-wide events.
15737 @var{services} must be a list of packages that provide an
15738 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
15739 and policy files. For example, to allow avahi-daemon to use the system bus,
15740 @var{services} must be equal to @code{(list avahi)}.
15743 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
15744 Return a service that runs the @code{elogind} login and
15745 seat management daemon. @uref{https://github.com/elogind/elogind,
15746 Elogind} exposes a D-Bus interface that can be used to know which users
15747 are logged in, know what kind of sessions they have open, suspend the
15748 system, inhibit system suspend, reboot the system, and other tasks.
15750 Elogind handles most system-level power events for a computer, for
15751 example suspending the system when a lid is closed, or shutting it down
15752 when the power button is pressed.
15754 The @var{config} keyword argument specifies the configuration for
15755 elogind, and should be the result of an @code{(elogind-configuration
15756 (@var{parameter} @var{value})...)} invocation. Available parameters and
15757 their default values are:
15760 @item kill-user-processes?
15762 @item kill-only-users
15764 @item kill-exclude-users
15766 @item inhibit-delay-max-seconds
15768 @item handle-power-key
15770 @item handle-suspend-key
15772 @item handle-hibernate-key
15774 @item handle-lid-switch
15776 @item handle-lid-switch-docked
15778 @item power-key-ignore-inhibited?
15780 @item suspend-key-ignore-inhibited?
15782 @item hibernate-key-ignore-inhibited?
15784 @item lid-switch-ignore-inhibited?
15786 @item holdoff-timeout-seconds
15790 @item idle-action-seconds
15792 @item runtime-directory-size-percent
15794 @item runtime-directory-size
15798 @item suspend-state
15799 @code{("mem" "standby" "freeze")}
15802 @item hibernate-state
15804 @item hibernate-mode
15805 @code{("platform" "shutdown")}
15806 @item hybrid-sleep-state
15808 @item hybrid-sleep-mode
15809 @code{("suspend" "platform" "shutdown")}
15813 @deffn {Scheme Procedure} accountsservice-service @
15814 [#:accountsservice @var{accountsservice}]
15815 Return a service that runs AccountsService, a system service that can
15816 list available accounts, change their passwords, and so on.
15817 AccountsService integrates with PolicyKit to enable unprivileged users
15818 to acquire the capability to modify their system configuration.
15819 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
15820 accountsservice web site} for more information.
15822 The @var{accountsservice} keyword argument is the @code{accountsservice}
15823 package to expose as a service.
15826 @deffn {Scheme Procedure} polkit-service @
15827 [#:polkit @var{polkit}]
15828 Return a service that runs the
15829 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
15830 management service}, which allows system administrators to grant access to
15831 privileged operations in a structured way. By querying the Polkit service, a
15832 privileged system component can know when it should grant additional
15833 capabilities to ordinary users. For example, an ordinary user can be granted
15834 the capability to suspend the system if the user is logged in locally.
15837 @defvr {Scheme Variable} polkit-wheel-service
15838 Service that adds the @code{wheel} group as admins to the Polkit
15839 service. This makes it so that users in the @code{wheel} group are queried
15840 for their own passwords when performing administrative actions instead of
15841 @code{root}'s, similar to the behaviour used by @code{sudo}.
15844 @defvr {Scheme Variable} upower-service-type
15845 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
15846 system-wide monitor for power consumption and battery levels, with the given
15847 configuration settings.
15849 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
15850 notably used by GNOME.
15853 @deftp {Data Type} upower-configuration
15854 Data type representation the configuration for UPower.
15858 @item @code{upower} (default: @var{upower})
15859 Package to use for @code{upower}.
15861 @item @code{watts-up-pro?} (default: @code{#f})
15862 Enable the Watts Up Pro device.
15864 @item @code{poll-batteries?} (default: @code{#t})
15865 Enable polling the kernel for battery level changes.
15867 @item @code{ignore-lid?} (default: @code{#f})
15868 Ignore the lid state, this can be useful if it's incorrect on a device.
15870 @item @code{use-percentage-for-policy?} (default: @code{#f})
15871 Whether battery percentage based policy should be used. The default is to use
15872 the time left, change to @code{#t} to use the percentage.
15874 @item @code{percentage-low} (default: @code{10})
15875 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15876 at which the battery is considered low.
15878 @item @code{percentage-critical} (default: @code{3})
15879 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15880 at which the battery is considered critical.
15882 @item @code{percentage-action} (default: @code{2})
15883 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15884 at which action will be taken.
15886 @item @code{time-low} (default: @code{1200})
15887 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15888 seconds at which the battery is considered low.
15890 @item @code{time-critical} (default: @code{300})
15891 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15892 seconds at which the battery is considered critical.
15894 @item @code{time-action} (default: @code{120})
15895 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15896 seconds at which action will be taken.
15898 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
15899 The action taken when @code{percentage-action} or @code{time-action} is
15900 reached (depending on the configuration of @code{use-percentage-for-policy?}).
15902 Possible values are:
15912 @code{'hybrid-sleep}.
15918 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
15919 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
15920 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
15921 notifications and ways to mount/unmount disks. Programs that talk to UDisks
15922 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
15925 @deffn {Scheme Variable} colord-service-type
15926 This is the type of the service that runs @command{colord}, a system
15927 service with a D-Bus
15928 interface to manage the color profiles of input and output devices such as
15929 screens and scanners. It is notably used by the GNOME Color Manager graphical
15930 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
15931 site} for more information.
15934 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
15935 Return a configuration allowing an application to access GeoClue
15936 location data. @var{name} is the Desktop ID of the application, without
15937 the @code{.desktop} part. If @var{allowed?} is true, the application
15938 will have access to location information by default. The boolean
15939 @var{system?} value indicates whether an application is a system component
15940 or not. Finally @var{users} is a list of UIDs of all users for which
15941 this application is allowed location info access. An empty users list
15942 means that all users are allowed.
15945 @cindex scanner access
15946 @deffn {Scheme Procedure} sane-service-type
15947 This service provides access to scanners @i{via}
15948 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
15952 @defvr {Scheme Variable} %standard-geoclue-applications
15953 The standard list of well-known GeoClue application configurations,
15954 granting authority to the GNOME date-and-time utility to ask for the
15955 current location in order to set the time zone, and allowing the
15956 IceCat and Epiphany web browsers to request location information.
15957 IceCat and Epiphany both query the user before allowing a web page to
15958 know the user's location.
15961 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
15962 [#:whitelist '()] @
15963 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
15964 [#:submit-data? #f]
15965 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
15966 [#:submission-nick "geoclue"] @
15967 [#:applications %standard-geoclue-applications]
15968 Return a service that runs the GeoClue location service. This service
15969 provides a D-Bus interface to allow applications to request access to a
15970 user's physical location, and optionally to add information to online
15971 location databases. See
15972 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
15973 web site} for more information.
15976 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
15977 [@w{#:auto-enable? #f}]
15978 Return a service that runs the @command{bluetoothd} daemon, which
15979 manages all the Bluetooth devices and provides a number of D-Bus
15980 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
15981 powered automatically at boot, which can be useful when using a
15982 bluetooth keyboard or mouse.
15984 Users need to be in the @code{lp} group to access the D-Bus service.
15987 @defvr {Scheme Variable} gnome-keyring-service-type
15988 This is the type of the service that adds the
15989 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
15990 value is a @code{gnome-keyring-configuration} object (see below.)
15992 This service adds the @code{gnome-keyring} package to the system profile
15993 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
15994 a user's login keyring when they log in or setting its password with passwd.
15997 @deftp {Data Type} gnome-keyring-configuration
15998 Configuration record for the GNOME Keyring service.
16001 @item @code{keyring} (default: @code{gnome-keyring})
16002 The GNOME keyring package to use.
16004 @item @code{pam-services}
16005 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
16006 services to extend, where @var{service} is the name of an existing
16007 service to extend and @var{kind} is one of @code{login} or
16010 If @code{login} is given, it adds an optional
16011 @code{pam_gnome_keyring.so} to the auth block without arguments and to
16012 the session block with @code{auto_start}. If @code{passwd} is given, it
16013 adds an optional @code{pam_gnome_keyring.so} to the password block
16016 By default, this field contains ``gdm-password'' with the value @code{login}
16017 and ``passwd'' is with the value @code{passwd}.
16022 @node Sound Services
16023 @subsection Sound Services
16025 @cindex sound support
16027 @cindex PulseAudio, sound support
16029 The @code{(gnu services sound)} module provides a service to configure the
16030 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
16031 preferred ALSA output driver.
16033 @deffn {Scheme Variable} alsa-service-type
16034 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
16035 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
16036 configuration file. The value for this type is a @command{alsa-configuration}
16037 record as in this example:
16040 (service alsa-service-type)
16043 See below for details about @code{alsa-configuration}.
16046 @deftp {Data Type} alsa-configuration
16047 Data type representing the configuration for @code{alsa-service}.
16050 @item @code{alsa-plugins} (default: @var{alsa-plugins})
16051 @code{alsa-plugins} package to use.
16053 @item @code{pulseaudio?} (default: @var{#t})
16054 Whether ALSA applications should transparently be made to use the
16055 @uref{http://www.pulseaudio.org/, PulseAudio} sound server.
16057 Using PulseAudio allows you to run several sound-producing applications
16058 at the same time and to individual control them @i{via}
16059 @command{pavucontrol}, among other things.
16061 @item @code{extra-options} (default: @var{""})
16062 String to append to the @file{/etc/asound.conf} file.
16067 Individual users who want to override the system configuration of ALSA can do
16068 it with the @file{~/.asoundrc} file:
16071 # In guix, we have to specify the absolute path for plugins.
16073 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
16076 # Routing ALSA to jack:
16077 # <http://jackaudio.org/faq/routing_alsa.html>.
16081 0 system:playback_1
16082 1 system:playback_2
16099 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
16102 @deffn {Scheme Variable} pulseaudio-service-type
16103 This is the type for the @uref{http://www.pulseaudio.org/, PulseAudio}
16104 sound server. It exists to allow system overrides of the default settings
16105 via @code{pulseaudio-configuration}, see below.
16108 This service on its own does not ensure, that the @code{pulseaudio} package
16109 exists on your machine. It merely adds configuration files for it, as
16110 detailed below. In the (admittedly unlikely) case, that you find yourself
16111 without a @code{pulseaudio} package, consider enabling it through the
16112 @code{alsa-service-type} above.
16116 @deftp {Data Type} pulseaudio-configuration
16117 Data type representing the configuration for @code{pulseaudio-service}.
16120 @item @var{client-conf} (default: @code{'()})
16121 List of settings to set in @file{client.conf}.
16122 Accepts a list of strings or a symbol-value pairs. A string will be
16123 inserted as-is with a newline added. A pair will be formatted as
16124 ``key = value'', again with a newline added.
16126 @item @var{daemon-conf} (default: @code{'((flat-volumes . no))})
16127 List of settings to set in @file{daemon.conf}, formatted just like
16130 @item @var{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
16131 Script file to use as as @file{default.pa}.
16133 @item @var{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
16134 Script file to use as as @file{system.pa}.
16138 @deffn {Scheme Variable} ladspa-service-type
16139 This service sets the @var{LADSPA_PATH} variable, so that programs, which
16140 respect it, e.g. PulseAudio, can load LADSPA plugins.
16142 The following example will setup the service to enable modules from the
16143 @code{swh-plugins} package:
16146 (service ladspa-service-type
16147 (ladspa-configuration (plugins (list swh-plugins))))
16150 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
16155 @node Database Services
16156 @subsection Database Services
16160 The @code{(gnu services databases)} module provides the following services.
16162 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
16163 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
16164 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
16165 Return a service that runs @var{postgresql}, the PostgreSQL database
16168 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
16169 creates a database cluster with @var{locale} as the default
16170 locale, stored in @var{data-directory}. It then listens on @var{port}.
16172 @cindex postgresql extension-packages
16173 Additional extensions are loaded from packages listed in
16174 @var{extension-packages}. Extensions are available at runtime. For instance,
16175 to create a geographic database using the @code{postgis} extension, a user can
16176 configure the postgresql-service as in this example:
16180 (use-package-modules databases geo)
16184 ;; postgresql is required to run `psql' but postgis is not required for
16185 ;; proper operation.
16186 (packages (cons* postgresql %base-packages))
16189 (postgresql-service #:extension-packages (list postgis))
16193 Then the extension becomes visible and you can initialise an empty geographic
16194 database in this way:
16198 > create database postgistest;
16199 > \connect postgistest;
16200 > create extension postgis;
16201 > create extension postgis_topology;
16204 There is no need to add this field for contrib extensions such as hstore or
16205 dblink as they are already loadable by postgresql. This field is only
16206 required to add extensions provided by other packages.
16209 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
16210 Return a service that runs @command{mysqld}, the MySQL or MariaDB
16213 The optional @var{config} argument specifies the configuration for
16214 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
16217 @deftp {Data Type} mysql-configuration
16218 Data type representing the configuration of @var{mysql-service}.
16221 @item @code{mysql} (default: @var{mariadb})
16222 Package object of the MySQL database server, can be either @var{mariadb}
16225 For MySQL, a temporary root password will be displayed at activation time.
16226 For MariaDB, the root password is empty.
16228 @item @code{port} (default: @code{3306})
16229 TCP port on which the database server listens for incoming connections.
16233 @defvr {Scheme Variable} memcached-service-type
16234 This is the service type for the @uref{https://memcached.org/,
16235 Memcached} service, which provides a distributed in memory cache. The
16236 value for the service type is a @code{memcached-configuration} object.
16240 (service memcached-service-type)
16243 @deftp {Data Type} memcached-configuration
16244 Data type representing the configuration of memcached.
16247 @item @code{memcached} (default: @code{memcached})
16248 The Memcached package to use.
16250 @item @code{interfaces} (default: @code{'("0.0.0.0")})
16251 Network interfaces on which to listen.
16253 @item @code{tcp-port} (default: @code{11211})
16254 Port on which to accept connections on,
16256 @item @code{udp-port} (default: @code{11211})
16257 Port on which to accept UDP connections on, a value of 0 will disable
16258 listening on a UDP socket.
16260 @item @code{additional-options} (default: @code{'()})
16261 Additional command line options to pass to @code{memcached}.
16265 @defvr {Scheme Variable} mongodb-service-type
16266 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
16267 The value for the service type is a @code{mongodb-configuration} object.
16271 (service mongodb-service-type)
16274 @deftp {Data Type} mongodb-configuration
16275 Data type representing the configuration of mongodb.
16278 @item @code{mongodb} (default: @code{mongodb})
16279 The MongoDB package to use.
16281 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
16282 The configuration file for MongoDB.
16284 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
16285 This value is used to create the directory, so that it exists and is
16286 owned by the mongodb user. It should match the data-directory which
16287 MongoDB is configured to use through the configuration file.
16291 @defvr {Scheme Variable} redis-service-type
16292 This is the service type for the @uref{https://redis.io/, Redis}
16293 key/value store, whose value is a @code{redis-configuration} object.
16296 @deftp {Data Type} redis-configuration
16297 Data type representing the configuration of redis.
16300 @item @code{redis} (default: @code{redis})
16301 The Redis package to use.
16303 @item @code{bind} (default: @code{"127.0.0.1"})
16304 Network interface on which to listen.
16306 @item @code{port} (default: @code{6379})
16307 Port on which to accept connections on, a value of 0 will disable
16308 listening on a TCP socket.
16310 @item @code{working-directory} (default: @code{"/var/lib/redis"})
16311 Directory in which to store the database and related files.
16315 @node Mail Services
16316 @subsection Mail Services
16320 The @code{(gnu services mail)} module provides Guix service definitions
16321 for email services: IMAP, POP3, and LMTP servers, as well as mail
16322 transport agents (MTAs). Lots of acronyms! These services are detailed
16323 in the subsections below.
16325 @subsubheading Dovecot Service
16327 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
16328 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
16331 By default, Dovecot does not need much configuration; the default
16332 configuration object created by @code{(dovecot-configuration)} will
16333 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
16334 certificate will be generated for TLS-protected connections, though
16335 Dovecot will also listen on cleartext ports by default. There are a
16336 number of options, though, which mail administrators might need to change,
16337 and as is the case with other services, Guix allows the system
16338 administrator to specify these parameters via a uniform Scheme interface.
16340 For example, to specify that mail is located at @code{maildir~/.mail},
16341 one would instantiate the Dovecot service like this:
16344 (dovecot-service #:config
16345 (dovecot-configuration
16346 (mail-location "maildir:~/.mail")))
16349 The available configuration parameters follow. Each parameter
16350 definition is preceded by its type; for example, @samp{string-list foo}
16351 indicates that the @code{foo} parameter should be specified as a list of
16352 strings. There is also a way to specify the configuration as a string,
16353 if you have an old @code{dovecot.conf} file that you want to port over
16354 from some other system; see the end for more details.
16356 @c The following documentation was initially generated by
16357 @c (generate-documentation) in (gnu services mail). Manually maintained
16358 @c documentation is better, so we shouldn't hesitate to edit below as
16359 @c needed. However if the change you want to make to this documentation
16360 @c can be done in an automated way, it's probably easier to change
16361 @c (generate-documentation) than to make it below and have to deal with
16362 @c the churn as dovecot updates.
16364 Available @code{dovecot-configuration} fields are:
16366 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
16367 The dovecot package.
16370 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
16371 A list of IPs or hosts where to listen for connections. @samp{*}
16372 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
16373 interfaces. If you want to specify non-default ports or anything more
16374 complex, customize the address and port fields of the
16375 @samp{inet-listener} of the specific services you are interested in.
16378 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
16379 List of protocols we want to serve. Available protocols include
16380 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
16382 Available @code{protocol-configuration} fields are:
16384 @deftypevr {@code{protocol-configuration} parameter} string name
16385 The name of the protocol.
16388 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
16389 UNIX socket path to the master authentication server to find users.
16390 This is used by imap (for shared users) and lda.
16391 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16394 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
16395 Space separated list of plugins to load.
16398 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
16399 Maximum number of IMAP connections allowed for a user from each IP
16400 address. NOTE: The username is compared case-sensitively.
16401 Defaults to @samp{10}.
16406 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
16407 List of services to enable. Available services include @samp{imap},
16408 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
16411 Available @code{service-configuration} fields are:
16413 @deftypevr {@code{service-configuration} parameter} string kind
16414 The service kind. Valid values include @code{director},
16415 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
16416 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
16417 @code{tcpwrap}, @code{quota-warning}, or anything else.
16420 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
16421 Listeners for the service. A listener is either a
16422 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
16423 an @code{inet-listener-configuration}.
16424 Defaults to @samp{()}.
16426 Available @code{unix-listener-configuration} fields are:
16428 @deftypevr {@code{unix-listener-configuration} parameter} string path
16429 Path to the file, relative to @code{base-dir} field. This is also used as
16433 @deftypevr {@code{unix-listener-configuration} parameter} string mode
16434 The access mode for the socket.
16435 Defaults to @samp{"0600"}.
16438 @deftypevr {@code{unix-listener-configuration} parameter} string user
16439 The user to own the socket.
16440 Defaults to @samp{""}.
16443 @deftypevr {@code{unix-listener-configuration} parameter} string group
16444 The group to own the socket.
16445 Defaults to @samp{""}.
16449 Available @code{fifo-listener-configuration} fields are:
16451 @deftypevr {@code{fifo-listener-configuration} parameter} string path
16452 Path to the file, relative to @code{base-dir} field. This is also used as
16456 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
16457 The access mode for the socket.
16458 Defaults to @samp{"0600"}.
16461 @deftypevr {@code{fifo-listener-configuration} parameter} string user
16462 The user to own the socket.
16463 Defaults to @samp{""}.
16466 @deftypevr {@code{fifo-listener-configuration} parameter} string group
16467 The group to own the socket.
16468 Defaults to @samp{""}.
16472 Available @code{inet-listener-configuration} fields are:
16474 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
16475 The protocol to listen for.
16478 @deftypevr {@code{inet-listener-configuration} parameter} string address
16479 The address on which to listen, or empty for all addresses.
16480 Defaults to @samp{""}.
16483 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
16484 The port on which to listen.
16487 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
16488 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
16490 Defaults to @samp{#t}.
16495 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
16496 Maximum number of simultaneous client connections per process. Once
16497 this number of connections is received, the next incoming connection
16498 will prompt Dovecot to spawn another process. If set to 0,
16499 @code{default-client-limit} is used instead.
16501 Defaults to @samp{0}.
16505 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
16506 Number of connections to handle before starting a new process.
16507 Typically the only useful values are 0 (unlimited) or 1. 1 is more
16508 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
16509 Defaults to @samp{1}.
16513 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
16514 Maximum number of processes that can exist for this service. If set to
16515 0, @code{default-process-limit} is used instead.
16517 Defaults to @samp{0}.
16521 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
16522 Number of processes to always keep waiting for more connections.
16523 Defaults to @samp{0}.
16526 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
16527 If you set @samp{service-count 0}, you probably need to grow
16529 Defaults to @samp{256000000}.
16534 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
16535 Dict configuration, as created by the @code{dict-configuration}
16538 Available @code{dict-configuration} fields are:
16540 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
16541 A list of key-value pairs that this dict should hold.
16542 Defaults to @samp{()}.
16547 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
16548 A list of passdb configurations, each one created by the
16549 @code{passdb-configuration} constructor.
16551 Available @code{passdb-configuration} fields are:
16553 @deftypevr {@code{passdb-configuration} parameter} string driver
16554 The driver that the passdb should use. Valid values include
16555 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
16557 Defaults to @samp{"pam"}.
16560 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
16561 Space separated list of arguments to the passdb driver.
16562 Defaults to @samp{""}.
16567 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
16568 List of userdb configurations, each one created by the
16569 @code{userdb-configuration} constructor.
16571 Available @code{userdb-configuration} fields are:
16573 @deftypevr {@code{userdb-configuration} parameter} string driver
16574 The driver that the userdb should use. Valid values include
16575 @samp{passwd} and @samp{static}.
16576 Defaults to @samp{"passwd"}.
16579 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
16580 Space separated list of arguments to the userdb driver.
16581 Defaults to @samp{""}.
16584 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
16585 Override fields from passwd.
16586 Defaults to @samp{()}.
16591 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
16592 Plug-in configuration, created by the @code{plugin-configuration}
16596 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
16597 List of namespaces. Each item in the list is created by the
16598 @code{namespace-configuration} constructor.
16600 Available @code{namespace-configuration} fields are:
16602 @deftypevr {@code{namespace-configuration} parameter} string name
16603 Name for this namespace.
16606 @deftypevr {@code{namespace-configuration} parameter} string type
16607 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
16608 Defaults to @samp{"private"}.
16611 @deftypevr {@code{namespace-configuration} parameter} string separator
16612 Hierarchy separator to use. You should use the same separator for
16613 all namespaces or some clients get confused. @samp{/} is usually a good
16614 one. The default however depends on the underlying mail storage
16616 Defaults to @samp{""}.
16619 @deftypevr {@code{namespace-configuration} parameter} string prefix
16620 Prefix required to access this namespace. This needs to be
16621 different for all namespaces. For example @samp{Public/}.
16622 Defaults to @samp{""}.
16625 @deftypevr {@code{namespace-configuration} parameter} string location
16626 Physical location of the mailbox. This is in the same format as
16627 mail_location, which is also the default for it.
16628 Defaults to @samp{""}.
16631 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
16632 There can be only one INBOX, and this setting defines which
16634 Defaults to @samp{#f}.
16637 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
16638 If namespace is hidden, it's not advertised to clients via NAMESPACE
16639 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
16640 useful when converting from another server with different namespaces
16641 which you want to deprecate but still keep working. For example you can
16642 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
16644 Defaults to @samp{#f}.
16647 @deftypevr {@code{namespace-configuration} parameter} boolean list?
16648 Show the mailboxes under this namespace with the LIST command. This
16649 makes the namespace visible for clients that do not support the NAMESPACE
16650 extension. The special @code{children} value lists child mailboxes, but
16651 hides the namespace prefix.
16652 Defaults to @samp{#t}.
16655 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
16656 Namespace handles its own subscriptions. If set to @code{#f}, the
16657 parent namespace handles them. The empty prefix should always have this
16659 Defaults to @samp{#t}.
16662 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
16663 List of predefined mailboxes in this namespace.
16664 Defaults to @samp{()}.
16666 Available @code{mailbox-configuration} fields are:
16668 @deftypevr {@code{mailbox-configuration} parameter} string name
16669 Name for this mailbox.
16672 @deftypevr {@code{mailbox-configuration} parameter} string auto
16673 @samp{create} will automatically create this mailbox.
16674 @samp{subscribe} will both create and subscribe to the mailbox.
16675 Defaults to @samp{"no"}.
16678 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
16679 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
16680 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
16681 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
16682 Defaults to @samp{()}.
16689 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
16690 Base directory where to store runtime data.
16691 Defaults to @samp{"/var/run/dovecot/"}.
16694 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
16695 Greeting message for clients.
16696 Defaults to @samp{"Dovecot ready."}.
16699 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
16700 List of trusted network ranges. Connections from these IPs are
16701 allowed to override their IP addresses and ports (for logging and for
16702 authentication checks). @samp{disable-plaintext-auth} is also ignored
16703 for these networks. Typically you would specify your IMAP proxy servers
16705 Defaults to @samp{()}.
16708 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
16709 List of login access check sockets (e.g.@: tcpwrap).
16710 Defaults to @samp{()}.
16713 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
16714 Show more verbose process titles (in ps). Currently shows user name
16715 and IP address. Useful for seeing who is actually using the IMAP
16716 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
16718 Defaults to @samp{#f}.
16721 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
16722 Should all processes be killed when Dovecot master process shuts down.
16723 Setting this to @code{#f} means that Dovecot can be upgraded without
16724 forcing existing client connections to close (although that could also
16725 be a problem if the upgrade is e.g.@: due to a security fix).
16726 Defaults to @samp{#t}.
16729 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
16730 If non-zero, run mail commands via this many connections to doveadm
16731 server, instead of running them directly in the same process.
16732 Defaults to @samp{0}.
16735 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
16736 UNIX socket or host:port used for connecting to doveadm server.
16737 Defaults to @samp{"doveadm-server"}.
16740 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
16741 List of environment variables that are preserved on Dovecot startup
16742 and passed down to all of its child processes. You can also give
16743 key=value pairs to always set specific settings.
16746 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
16747 Disable LOGIN command and all other plaintext authentications unless
16748 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
16749 matches the local IP (i.e.@: you're connecting from the same computer),
16750 the connection is considered secure and plaintext authentication is
16751 allowed. See also ssl=required setting.
16752 Defaults to @samp{#t}.
16755 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
16756 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
16757 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
16758 for caching to be used.
16759 Defaults to @samp{0}.
16762 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
16763 Time to live for cached data. After TTL expires the cached record
16764 is no longer used, *except* if the main database lookup returns internal
16765 failure. We also try to handle password changes automatically: If
16766 user's previous authentication was successful, but this one wasn't, the
16767 cache isn't used. For now this works only with plaintext
16769 Defaults to @samp{"1 hour"}.
16772 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
16773 TTL for negative hits (user not found, password mismatch).
16774 0 disables caching them completely.
16775 Defaults to @samp{"1 hour"}.
16778 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
16779 List of realms for SASL authentication mechanisms that need them.
16780 You can leave it empty if you don't want to support multiple realms.
16781 Many clients simply use the first one listed here, so keep the default
16783 Defaults to @samp{()}.
16786 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
16787 Default realm/domain to use if none was specified. This is used for
16788 both SASL realms and appending @@domain to username in plaintext
16790 Defaults to @samp{""}.
16793 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
16794 List of allowed characters in username. If the user-given username
16795 contains a character not listed in here, the login automatically fails.
16796 This is just an extra check to make sure user can't exploit any
16797 potential quote escaping vulnerabilities with SQL/LDAP databases. If
16798 you want to allow all characters, set this value to empty.
16799 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
16802 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
16803 Username character translations before it's looked up from
16804 databases. The value contains series of from -> to characters. For
16805 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
16806 translated to @samp{@@}.
16807 Defaults to @samp{""}.
16810 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
16811 Username formatting before it's looked up from databases. You can
16812 use the standard variables here, e.g.@: %Lu would lowercase the username,
16813 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
16814 change the @samp{@@} into @samp{-AT-}. This translation is done after
16815 @samp{auth-username-translation} changes.
16816 Defaults to @samp{"%Lu"}.
16819 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
16820 If you want to allow master users to log in by specifying the master
16821 username within the normal username string (i.e.@: not using SASL
16822 mechanism's support for it), you can specify the separator character
16823 here. The format is then <username><separator><master username>.
16824 UW-IMAP uses @samp{*} as the separator, so that could be a good
16826 Defaults to @samp{""}.
16829 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
16830 Username to use for users logging in with ANONYMOUS SASL
16832 Defaults to @samp{"anonymous"}.
16835 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
16836 Maximum number of dovecot-auth worker processes. They're used to
16837 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
16838 They're automatically created and destroyed as needed.
16839 Defaults to @samp{30}.
16842 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
16843 Host name to use in GSSAPI principal names. The default is to use
16844 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
16845 allow all keytab entries.
16846 Defaults to @samp{""}.
16849 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
16850 Kerberos keytab to use for the GSSAPI mechanism. Will use the
16851 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
16852 need to change the auth service to run as root to be able to read this
16854 Defaults to @samp{""}.
16857 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
16858 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
16859 and @samp{ntlm-auth} helper.
16860 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
16861 Defaults to @samp{#f}.
16864 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
16865 Path for Samba's @samp{ntlm-auth} helper binary.
16866 Defaults to @samp{"/usr/bin/ntlm_auth"}.
16869 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
16870 Time to delay before replying to failed authentications.
16871 Defaults to @samp{"2 secs"}.
16874 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
16875 Require a valid SSL client certificate or the authentication
16877 Defaults to @samp{#f}.
16880 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
16881 Take the username from client's SSL certificate, using
16882 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
16884 Defaults to @samp{#f}.
16887 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
16888 List of wanted authentication mechanisms. Supported mechanisms are:
16889 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
16890 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
16891 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
16892 @samp{disable-plaintext-auth} setting.
16895 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
16896 List of IPs or hostnames to all director servers, including ourself.
16897 Ports can be specified as ip:port. The default port is the same as what
16898 director service's @samp{inet-listener} is using.
16899 Defaults to @samp{()}.
16902 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
16903 List of IPs or hostnames to all backend mail servers. Ranges are
16904 allowed too, like 10.0.0.10-10.0.0.30.
16905 Defaults to @samp{()}.
16908 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
16909 How long to redirect users to a specific server after it no longer
16910 has any connections.
16911 Defaults to @samp{"15 min"}.
16914 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
16915 How the username is translated before being hashed. Useful values
16916 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
16917 are shared within domain.
16918 Defaults to @samp{"%Lu"}.
16921 @deftypevr {@code{dovecot-configuration} parameter} string log-path
16922 Log file to use for error messages. @samp{syslog} logs to syslog,
16923 @samp{/dev/stderr} logs to stderr.
16924 Defaults to @samp{"syslog"}.
16927 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
16928 Log file to use for informational messages. Defaults to
16930 Defaults to @samp{""}.
16933 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
16934 Log file to use for debug messages. Defaults to
16935 @samp{info-log-path}.
16936 Defaults to @samp{""}.
16939 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
16940 Syslog facility to use if you're logging to syslog. Usually if you
16941 don't want to use @samp{mail}, you'll use local0..local7. Also other
16942 standard facilities are supported.
16943 Defaults to @samp{"mail"}.
16946 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
16947 Log unsuccessful authentication attempts and the reasons why they
16949 Defaults to @samp{#f}.
16952 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
16953 In case of password mismatches, log the attempted password. Valid
16954 values are no, plain and sha1. sha1 can be useful for detecting brute
16955 force password attempts vs. user simply trying the same password over
16956 and over again. You can also truncate the value to n chars by appending
16957 ":n" (e.g.@: sha1:6).
16958 Defaults to @samp{"no"}.
16961 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
16962 Even more verbose logging for debugging purposes. Shows for example
16964 Defaults to @samp{#f}.
16967 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
16968 In case of password mismatches, log the passwords and used scheme so
16969 the problem can be debugged. Enabling this also enables
16971 Defaults to @samp{#f}.
16974 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
16975 Enable mail process debugging. This can help you figure out why
16976 Dovecot isn't finding your mails.
16977 Defaults to @samp{#f}.
16980 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
16981 Show protocol level SSL errors.
16982 Defaults to @samp{#f}.
16985 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
16986 Prefix for each line written to log file. % codes are in
16987 strftime(3) format.
16988 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
16991 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
16992 List of elements we want to log. The elements which have a
16993 non-empty variable value are joined together to form a comma-separated
16997 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
16998 Login log format. %s contains @samp{login-log-format-elements}
16999 string, %$ contains the data we want to log.
17000 Defaults to @samp{"%$: %s"}.
17003 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
17004 Log prefix for mail processes. See doc/wiki/Variables.txt for list
17005 of possible variables you can use.
17006 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
17009 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
17010 Format to use for logging mail deliveries. You can use variables:
17013 Delivery status message (e.g.@: @samp{saved to INBOX})
17025 Defaults to @samp{"msgid=%m: %$"}.
17028 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
17029 Location for users' mailboxes. The default is empty, which means
17030 that Dovecot tries to find the mailboxes automatically. This won't work
17031 if the user doesn't yet have any mail, so you should explicitly tell
17032 Dovecot the full location.
17034 If you're using mbox, giving a path to the INBOX
17035 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
17036 where the other mailboxes are kept. This is called the "root mail
17037 directory", and it must be the first path given in the
17038 @samp{mail-location} setting.
17040 There are a few special variables you can use, eg.:
17046 user part in user@@domain, same as %u if there's no domain
17048 domain part in user@@domain, empty if there's no domain
17053 See doc/wiki/Variables.txt for full list. Some examples:
17055 @item maildir:~/Maildir
17056 @item mbox:~/mail:INBOX=/var/mail/%u
17057 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
17059 Defaults to @samp{""}.
17062 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
17063 System user and group used to access mails. If you use multiple,
17064 userdb can override these by returning uid or gid fields. You can use
17065 either numbers or names. <doc/wiki/UserIds.txt>.
17066 Defaults to @samp{""}.
17069 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
17071 Defaults to @samp{""}.
17074 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
17075 Group to enable temporarily for privileged operations. Currently
17076 this is used only with INBOX when either its initial creation or
17077 dotlocking fails. Typically this is set to "mail" to give access to
17079 Defaults to @samp{""}.
17082 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
17083 Grant access to these supplementary groups for mail processes.
17084 Typically these are used to set up access to shared mailboxes. Note
17085 that it may be dangerous to set these if users can create
17086 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
17087 could allow a user to delete others' mailboxes, or ln -s
17088 /secret/shared/box ~/mail/mybox would allow reading it).
17089 Defaults to @samp{""}.
17092 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
17093 Allow full file system access to clients. There's no access checks
17094 other than what the operating system does for the active UID/GID. It
17095 works with both maildir and mboxes, allowing you to prefix mailboxes
17096 names with e.g.@: /path/ or ~user/.
17097 Defaults to @samp{#f}.
17100 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
17101 Don't use mmap() at all. This is required if you store indexes to
17102 shared file systems (NFS or clustered file system).
17103 Defaults to @samp{#f}.
17106 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
17107 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
17108 supports @samp{O_EXCL} since version 3, so this should be safe to use
17109 nowadays by default.
17110 Defaults to @samp{#t}.
17113 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
17114 When to use fsync() or fdatasync() calls:
17117 Whenever necessary to avoid losing important data
17119 Useful with e.g.@: NFS when write()s are delayed
17121 Never use it (best performance, but crashes can lose data).
17123 Defaults to @samp{"optimized"}.
17126 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
17127 Mail storage exists in NFS. Set this to yes to make Dovecot flush
17128 NFS caches whenever needed. If you're using only a single mail server
17130 Defaults to @samp{#f}.
17133 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
17134 Mail index files also exist in NFS. Setting this to yes requires
17135 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
17136 Defaults to @samp{#f}.
17139 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
17140 Locking method for index files. Alternatives are fcntl, flock and
17141 dotlock. Dotlocking uses some tricks which may create more disk I/O
17142 than other locking methods. NFS users: flock doesn't work, remember to
17143 change @samp{mmap-disable}.
17144 Defaults to @samp{"fcntl"}.
17147 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
17148 Directory in which LDA/LMTP temporarily stores incoming mails >128
17150 Defaults to @samp{"/tmp"}.
17153 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
17154 Valid UID range for users. This is mostly to make sure that users can't
17155 log in as daemons or other system users. Note that denying root logins is
17156 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
17158 Defaults to @samp{500}.
17161 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
17163 Defaults to @samp{0}.
17166 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
17167 Valid GID range for users. Users having non-valid GID as primary group ID
17168 aren't allowed to log in. If user belongs to supplementary groups with
17169 non-valid GIDs, those groups are not set.
17170 Defaults to @samp{1}.
17173 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
17175 Defaults to @samp{0}.
17178 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
17179 Maximum allowed length for mail keyword name. It's only forced when
17180 trying to create new keywords.
17181 Defaults to @samp{50}.
17184 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
17185 List of directories under which chrooting is allowed for mail
17186 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
17187 too). This setting doesn't affect @samp{login-chroot}
17188 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
17189 "/./" in home dirs are ignored. WARNING: Never add directories here
17190 which local users can modify, that may lead to root exploit. Usually
17191 this should be done only if you don't allow shell access for users.
17192 <doc/wiki/Chrooting.txt>.
17193 Defaults to @samp{()}.
17196 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
17197 Default chroot directory for mail processes. This can be overridden
17198 for specific users in user database by giving /./ in user's home
17199 directory (e.g.@: /home/./user chroots into /home). Note that usually
17200 there is no real need to do chrooting, Dovecot doesn't allow users to
17201 access files outside their mail directory anyway. If your home
17202 directories are prefixed with the chroot directory, append "/."@: to
17203 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
17204 Defaults to @samp{""}.
17207 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
17208 UNIX socket path to master authentication server to find users.
17209 This is used by imap (for shared users) and lda.
17210 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17213 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
17214 Directory where to look up mail plugins.
17215 Defaults to @samp{"/usr/lib/dovecot"}.
17218 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
17219 List of plugins to load for all services. Plugins specific to IMAP,
17220 LDA, etc.@: are added to this list in their own .conf files.
17221 Defaults to @samp{()}.
17224 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
17225 The minimum number of mails in a mailbox before updates are done to
17226 cache file. This allows optimizing Dovecot's behavior to do less disk
17227 writes at the cost of more disk reads.
17228 Defaults to @samp{0}.
17231 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
17232 When IDLE command is running, mailbox is checked once in a while to
17233 see if there are any new mails or other changes. This setting defines
17234 the minimum time to wait between those checks. Dovecot can also use
17235 dnotify, inotify and kqueue to find out immediately when changes
17237 Defaults to @samp{"30 secs"}.
17240 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
17241 Save mails with CR+LF instead of plain LF. This makes sending those
17242 mails take less CPU, especially with sendfile() syscall with Linux and
17243 FreeBSD. But it also creates a bit more disk I/O which may just make it
17244 slower. Also note that if other software reads the mboxes/maildirs,
17245 they may handle the extra CRs wrong and cause problems.
17246 Defaults to @samp{#f}.
17249 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
17250 By default LIST command returns all entries in maildir beginning
17251 with a dot. Enabling this option makes Dovecot return only entries
17252 which are directories. This is done by stat()ing each entry, so it
17253 causes more disk I/O.
17254 (For systems setting struct @samp{dirent->d_type} this check is free
17255 and it's done always regardless of this setting).
17256 Defaults to @samp{#f}.
17259 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
17260 When copying a message, do it with hard links whenever possible.
17261 This makes the performance much better, and it's unlikely to have any
17263 Defaults to @samp{#t}.
17266 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
17267 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
17268 directory only when its mtime changes unexpectedly or when we can't find
17269 the mail otherwise.
17270 Defaults to @samp{#f}.
17273 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
17274 Which locking methods to use for locking mbox. There are four
17279 Create <mailbox>.lock file. This is the oldest and most NFS-safe
17280 solution. If you want to use /var/mail/ like directory, the users will
17281 need write access to that directory.
17283 Same as dotlock, but if it fails because of permissions or because there
17284 isn't enough disk space, just skip it.
17286 Use this if possible. Works with NFS too if lockd is used.
17288 May not exist in all systems. Doesn't work with NFS.
17290 May not exist in all systems. Doesn't work with NFS.
17293 You can use multiple locking methods; if you do the order they're declared
17294 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
17295 locking methods as well. Some operating systems don't allow using some of
17296 them simultaneously.
17299 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
17303 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
17304 Maximum time to wait for lock (all of them) before aborting.
17305 Defaults to @samp{"5 mins"}.
17308 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
17309 If dotlock exists but the mailbox isn't modified in any way,
17310 override the lock file after this much time.
17311 Defaults to @samp{"2 mins"}.
17314 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
17315 When mbox changes unexpectedly we have to fully read it to find out
17316 what changed. If the mbox is large this can take a long time. Since
17317 the change is usually just a newly appended mail, it'd be faster to
17318 simply read the new mails. If this setting is enabled, Dovecot does
17319 this but still safely fallbacks to re-reading the whole mbox file
17320 whenever something in mbox isn't how it's expected to be. The only real
17321 downside to this setting is that if some other MUA changes message
17322 flags, Dovecot doesn't notice it immediately. Note that a full sync is
17323 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
17324 Defaults to @samp{#t}.
17327 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
17328 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
17329 EXAMINE, EXPUNGE or CHECK commands. If this is set,
17330 @samp{mbox-dirty-syncs} is ignored.
17331 Defaults to @samp{#f}.
17334 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
17335 Delay writing mbox headers until doing a full write sync (EXPUNGE
17336 and CHECK commands and when closing the mailbox). This is especially
17337 useful for POP3 where clients often delete all mails. The downside is
17338 that our changes aren't immediately visible to other MUAs.
17339 Defaults to @samp{#t}.
17342 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
17343 If mbox size is smaller than this (e.g.@: 100k), don't write index
17344 files. If an index file already exists it's still read, just not
17346 Defaults to @samp{0}.
17349 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
17350 Maximum dbox file size until it's rotated.
17351 Defaults to @samp{10000000}.
17354 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
17355 Maximum dbox file age until it's rotated. Typically in days. Day
17356 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
17358 Defaults to @samp{"1d"}.
17361 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
17362 When creating new mdbox files, immediately preallocate their size to
17363 @samp{mdbox-rotate-size}. This setting currently works only in Linux
17364 with some file systems (ext4, xfs).
17365 Defaults to @samp{#f}.
17368 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
17369 sdbox and mdbox support saving mail attachments to external files,
17370 which also allows single instance storage for them. Other backends
17371 don't support this for now.
17373 WARNING: This feature hasn't been tested much yet. Use at your own risk.
17375 Directory root where to store mail attachments. Disabled, if empty.
17376 Defaults to @samp{""}.
17379 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
17380 Attachments smaller than this aren't saved externally. It's also
17381 possible to write a plugin to disable saving specific attachments
17383 Defaults to @samp{128000}.
17386 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
17387 File system backend to use for saving attachments:
17390 No SiS done by Dovecot (but this might help FS's own deduplication)
17392 SiS with immediate byte-by-byte comparison during saving
17393 @item sis-queue posix
17394 SiS with delayed comparison and deduplication.
17396 Defaults to @samp{"sis posix"}.
17399 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
17400 Hash format to use in attachment filenames. You can add any text and
17401 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
17402 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
17403 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
17404 Defaults to @samp{"%@{sha1@}"}.
17407 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
17409 Defaults to @samp{100}.
17412 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
17414 Defaults to @samp{1000}.
17417 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
17418 Default VSZ (virtual memory size) limit for service processes.
17419 This is mainly intended to catch and kill processes that leak memory
17420 before they eat up everything.
17421 Defaults to @samp{256000000}.
17424 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
17425 Login user is internally used by login processes. This is the most
17426 untrusted user in Dovecot system. It shouldn't have access to anything
17428 Defaults to @samp{"dovenull"}.
17431 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
17432 Internal user is used by unprivileged processes. It should be
17433 separate from login user, so that login processes can't disturb other
17435 Defaults to @samp{"dovecot"}.
17438 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
17439 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
17440 Defaults to @samp{"required"}.
17443 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
17444 PEM encoded X.509 SSL/TLS certificate (public key).
17445 Defaults to @samp{"</etc/dovecot/default.pem"}.
17448 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
17449 PEM encoded SSL/TLS private key. The key is opened before
17450 dropping root privileges, so keep the key file unreadable by anyone but
17452 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
17455 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
17456 If key file is password protected, give the password here.
17457 Alternatively give it when starting dovecot with -p parameter. Since
17458 this file is often world-readable, you may want to place this setting
17459 instead to a different.
17460 Defaults to @samp{""}.
17463 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
17464 PEM encoded trusted certificate authority. Set this only if you
17465 intend to use @samp{ssl-verify-client-cert? #t}. The file should
17466 contain the CA certificate(s) followed by the matching
17467 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
17468 Defaults to @samp{""}.
17471 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
17472 Require that CRL check succeeds for client certificates.
17473 Defaults to @samp{#t}.
17476 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
17477 Request client to send a certificate. If you also want to require
17478 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
17479 Defaults to @samp{#f}.
17482 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
17483 Which field from certificate to use for username. commonName and
17484 x500UniqueIdentifier are the usual choices. You'll also need to set
17485 @samp{auth-ssl-username-from-cert? #t}.
17486 Defaults to @samp{"commonName"}.
17489 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
17490 Minimum SSL protocol version to accept.
17491 Defaults to @samp{"TLSv1"}.
17494 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
17495 SSL ciphers to use.
17496 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
17499 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
17500 SSL crypto device to use, for valid values run "openssl engine".
17501 Defaults to @samp{""}.
17504 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
17505 Address to use when sending rejection mails.
17506 %d expands to recipient domain.
17507 Defaults to @samp{"postmaster@@%d"}.
17510 @deftypevr {@code{dovecot-configuration} parameter} string hostname
17511 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
17512 and in LMTP replies. Default is the system's real hostname@@domain.
17513 Defaults to @samp{""}.
17516 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
17517 If user is over quota, return with temporary failure instead of
17519 Defaults to @samp{#f}.
17522 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
17523 Binary to use for sending mails.
17524 Defaults to @samp{"/usr/sbin/sendmail"}.
17527 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
17528 If non-empty, send mails via this SMTP host[:port] instead of
17530 Defaults to @samp{""}.
17533 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
17534 Subject: header to use for rejection mails. You can use the same
17535 variables as for @samp{rejection-reason} below.
17536 Defaults to @samp{"Rejected: %s"}.
17539 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
17540 Human readable error message for rejection mails. You can use
17553 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
17556 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
17557 Delimiter character between local-part and detail in email
17559 Defaults to @samp{"+"}.
17562 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
17563 Header where the original recipient address (SMTP's RCPT TO:
17564 address) is taken from if not available elsewhere. With dovecot-lda -a
17565 parameter overrides this. A commonly used header for this is
17567 Defaults to @samp{""}.
17570 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
17571 Should saving a mail to a nonexistent mailbox automatically create
17573 Defaults to @samp{#f}.
17576 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
17577 Should automatically created mailboxes be also automatically
17579 Defaults to @samp{#f}.
17582 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
17583 Maximum IMAP command line length. Some clients generate very long
17584 command lines with huge mailboxes, so you may need to raise this if you
17585 get "Too long argument" or "IMAP command line too large" errors
17587 Defaults to @samp{64000}.
17590 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
17591 IMAP logout format string:
17594 total number of bytes read from client
17596 total number of bytes sent to client.
17598 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
17599 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@}"}.
17602 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
17603 Override the IMAP CAPABILITY response. If the value begins with '+',
17604 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
17605 Defaults to @samp{""}.
17608 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
17609 How long to wait between "OK Still here" notifications when client
17611 Defaults to @samp{"2 mins"}.
17614 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
17615 ID field names and values to send to clients. Using * as the value
17616 makes Dovecot use the default value. The following fields have default
17617 values currently: name, version, os, os-version, support-url,
17619 Defaults to @samp{""}.
17622 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
17623 ID fields sent by client to log. * means everything.
17624 Defaults to @samp{""}.
17627 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
17628 Workarounds for various client bugs:
17631 @item delay-newmail
17632 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
17633 CHECK commands. Some clients ignore them otherwise, for example OSX
17634 Mail (<v2.1). Outlook Express breaks more badly though, without this it
17635 may show user "Message no longer in server" errors. Note that OE6
17636 still breaks even with this workaround if synchronization is set to
17639 @item tb-extra-mailbox-sep
17640 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
17641 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
17642 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
17644 @item tb-lsub-flags
17645 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
17646 This makes Thunderbird realize they aren't selectable and show them
17647 greyed out, instead of only later giving "not selectable" popup error.
17649 Defaults to @samp{()}.
17652 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
17653 Host allowed in URLAUTH URLs sent by client. "*" allows all.
17654 Defaults to @samp{""}.
17658 Whew! Lots of configuration options. The nice thing about it though is
17659 that Guix has a complete interface to Dovecot's configuration
17660 language. This allows not only a nice way to declare configurations,
17661 but also offers reflective capabilities as well: users can write code to
17662 inspect and transform configurations from within Scheme.
17664 However, it could be that you just want to get a @code{dovecot.conf} up
17665 and running. In that case, you can pass an
17666 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
17667 @code{dovecot-service}. As its name indicates, an opaque configuration
17668 does not have easy reflective capabilities.
17670 Available @code{opaque-dovecot-configuration} fields are:
17672 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
17673 The dovecot package.
17676 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
17677 The contents of the @code{dovecot.conf}, as a string.
17680 For example, if your @code{dovecot.conf} is just the empty string, you
17681 could instantiate a dovecot service like this:
17684 (dovecot-service #:config
17685 (opaque-dovecot-configuration
17689 @subsubheading OpenSMTPD Service
17691 @deffn {Scheme Variable} opensmtpd-service-type
17692 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
17693 service, whose value should be an @code{opensmtpd-configuration} object
17694 as in this example:
17697 (service opensmtpd-service-type
17698 (opensmtpd-configuration
17699 (config-file (local-file "./my-smtpd.conf"))))
17703 @deftp {Data Type} opensmtpd-configuration
17704 Data type representing the configuration of opensmtpd.
17707 @item @code{package} (default: @var{opensmtpd})
17708 Package object of the OpenSMTPD SMTP server.
17710 @item @code{config-file} (default: @code{%default-opensmtpd-file})
17711 File-like object of the OpenSMTPD configuration file to use. By default
17712 it listens on the loopback network interface, and allows for mail from
17713 users and daemons on the local machine, as well as permitting email to
17714 remote servers. Run @command{man smtpd.conf} for more information.
17719 @subsubheading Exim Service
17721 @cindex mail transfer agent (MTA)
17722 @cindex MTA (mail transfer agent)
17725 @deffn {Scheme Variable} exim-service-type
17726 This is the type of the @uref{https://exim.org, Exim} mail transfer
17727 agent (MTA), whose value should be an @code{exim-configuration} object
17728 as in this example:
17731 (service exim-service-type
17732 (exim-configuration
17733 (config-file (local-file "./my-exim.conf"))))
17737 In order to use an @code{exim-service-type} service you must also have a
17738 @code{mail-aliases-service-type} service present in your
17739 @code{operating-system} (even if it has no aliases).
17741 @deftp {Data Type} exim-configuration
17742 Data type representing the configuration of exim.
17745 @item @code{package} (default: @var{exim})
17746 Package object of the Exim server.
17748 @item @code{config-file} (default: @code{#f})
17749 File-like object of the Exim configuration file to use. If its value is
17750 @code{#f} then use the default configuration file from the package
17751 provided in @code{package}. The resulting configuration file is loaded
17752 after setting the @code{exim_user} and @code{exim_group} configuration
17758 @subsubheading Getmail service
17763 @deffn {Scheme Variable} getmail-service-type
17764 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
17765 mail retriever, whose value should be an @code{getmail-configuration}.
17768 Available @code{getmail-configuration} fields are:
17770 @deftypevr {@code{getmail-configuration} parameter} symbol name
17771 A symbol to identify the getmail service.
17773 Defaults to @samp{"unset"}.
17777 @deftypevr {@code{getmail-configuration} parameter} package package
17778 The getmail package to use.
17782 @deftypevr {@code{getmail-configuration} parameter} string user
17783 The user to run getmail as.
17785 Defaults to @samp{"getmail"}.
17789 @deftypevr {@code{getmail-configuration} parameter} string group
17790 The group to run getmail as.
17792 Defaults to @samp{"getmail"}.
17796 @deftypevr {@code{getmail-configuration} parameter} string directory
17797 The getmail directory to use.
17799 Defaults to @samp{"/var/lib/getmail/default"}.
17803 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
17804 The getmail configuration file to use.
17806 Available @code{getmail-configuration-file} fields are:
17808 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
17809 What mail account to retrieve mail from, and how to access that account.
17811 Available @code{getmail-retriever-configuration} fields are:
17813 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
17814 The type of mail retriever to use. Valid values include @samp{passwd}
17817 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
17821 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
17822 Username to login to the mail server with.
17824 Defaults to @samp{unset}.
17828 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
17829 Username to login to the mail server with.
17831 Defaults to @samp{unset}.
17835 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
17836 Port number to connect to.
17838 Defaults to @samp{#f}.
17842 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
17843 Override fields from passwd.
17845 Defaults to @samp{""}.
17849 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
17850 Override fields from passwd.
17852 Defaults to @samp{()}.
17856 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
17857 PEM-formatted key file to use for the TLS negotiation.
17859 Defaults to @samp{""}.
17863 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
17864 PEM-formatted certificate file to use for the TLS negotiation.
17866 Defaults to @samp{""}.
17870 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
17871 CA certificates to use.
17873 Defaults to @samp{""}.
17877 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
17878 Extra retriever parameters.
17880 Defaults to @samp{()}.
17886 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
17887 What to do with retrieved messages.
17889 Available @code{getmail-destination-configuration} fields are:
17891 @deftypevr {@code{getmail-destination-configuration} parameter} string type
17892 The type of mail destination. Valid values include @samp{Maildir},
17893 @samp{Mboxrd} and @samp{MDA_external}.
17895 Defaults to @samp{unset}.
17899 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
17900 The path option for the mail destination. The behaviour depends on the
17903 Defaults to @samp{""}.
17907 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
17908 Extra destination parameters
17910 Defaults to @samp{()}.
17916 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
17919 Available @code{getmail-options-configuration} fields are:
17921 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
17922 If set to @samp{0}, getmail will only print warnings and errors. A
17923 value of @samp{1} means that messages will be printed about retrieving
17924 and deleting messages. If set to @samp{2}, getmail will print messages
17925 about each of it's actions.
17927 Defaults to @samp{1}.
17931 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
17932 If true, getmail will retrieve all available messages. Otherwise it
17933 will only retrieve messages it hasn't seen previously.
17935 Defaults to @samp{#t}.
17939 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
17940 If set to true, messages will be deleted from the server after
17941 retrieving and successfully delivering them. Otherwise, messages will
17942 be left on the server.
17944 Defaults to @samp{#f}.
17948 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
17949 Getmail will delete messages this number of days after seeing them, if
17950 they have been delivered. This means messages will be left on the
17951 server this number of days after delivering them. A value of @samp{0}
17952 disabled this feature.
17954 Defaults to @samp{0}.
17958 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
17959 Delete messages larger than this of bytes after retrieving them, even if
17960 the delete and delete-after options are disabled. A value of @samp{0}
17961 disables this feature.
17963 Defaults to @samp{0}.
17967 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
17968 Retrieve messages totalling up to this number of bytes before closing
17969 the session with the server. A value of @samp{0} disables this feature.
17971 Defaults to @samp{0}.
17975 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
17976 Don't retrieve messages larger than this number of bytes. A value of
17977 @samp{0} disables this feature.
17979 Defaults to @samp{0}.
17983 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
17984 If true, getmail will add a Delivered-To header to messages.
17986 Defaults to @samp{#t}.
17990 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
17991 If set, getmail adds a Received header to the messages.
17993 Defaults to @samp{#t}.
17997 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
17998 Getmail will record a log of its actions to the named file. A value of
17999 @samp{""} disables this feature.
18001 Defaults to @samp{""}.
18005 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
18006 If true, getmail will record a log of its actions using the system
18009 Defaults to @samp{#f}.
18013 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
18014 If true, getmail will log information about messages not retrieved and
18015 the reason for not retrieving them, as well as starting and ending
18018 Defaults to @samp{#f}.
18022 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
18023 Extra options to include.
18025 Defaults to @samp{()}.
18033 @deftypevr {@code{getmail-configuration} parameter} list idle
18034 A list of mailboxes that getmail should wait on the server for new mail
18035 notifications. This depends on the server supporting the IDLE
18038 Defaults to @samp{()}.
18042 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
18043 Environment variables to set for getmail.
18045 Defaults to @samp{()}.
18049 @subsubheading Mail Aliases Service
18051 @cindex email aliases
18052 @cindex aliases, for email addresses
18054 @deffn {Scheme Variable} mail-aliases-service-type
18055 This is the type of the service which provides @code{/etc/aliases},
18056 specifying how to deliver mail to users on this system.
18059 (service mail-aliases-service-type
18060 '(("postmaster" "bob")
18061 ("bob" "bob@@example.com" "bob@@example2.com")))
18065 The configuration for a @code{mail-aliases-service-type} service is an
18066 association list denoting how to deliver mail that comes to this
18067 system. Each entry is of the form @code{(alias addresses ...)}, with
18068 @code{alias} specifying the local alias and @code{addresses} specifying
18069 where to deliver this user's mail.
18071 The aliases aren't required to exist as users on the local system. In
18072 the above example, there doesn't need to be a @code{postmaster} entry in
18073 the @code{operating-system}'s @code{user-accounts} in order to deliver
18074 the @code{postmaster} mail to @code{bob} (which subsequently would
18075 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
18077 @subsubheading GNU Mailutils IMAP4 Daemon
18078 @cindex GNU Mailutils IMAP4 Daemon
18080 @deffn {Scheme Variable} imap4d-service-type
18081 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
18082 mailutils, GNU Mailutils Manual}), whose value should be an
18083 @code{imap4d-configuration} object as in this example:
18086 (service imap4d-service-type
18087 (imap4d-configuration
18088 (config-file (local-file "imap4d.conf"))))
18092 @deftp {Data Type} imap4d-configuration
18093 Data type representing the configuration of @command{imap4d}.
18096 @item @code{package} (default: @code{mailutils})
18097 The package that provides @command{imap4d}.
18099 @item @code{config-file} (default: @code{%default-imap4d-config-file})
18100 File-like object of the configuration file to use, by default it will listen
18101 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
18102 Mailutils Manual}, for details.
18107 @node Messaging Services
18108 @subsection Messaging Services
18113 The @code{(gnu services messaging)} module provides Guix service
18114 definitions for messaging services: currently only Prosody is supported.
18116 @subsubheading Prosody Service
18118 @deffn {Scheme Variable} prosody-service-type
18119 This is the type for the @uref{https://prosody.im, Prosody XMPP
18120 communication server}. Its value must be a @code{prosody-configuration}
18121 record as in this example:
18124 (service prosody-service-type
18125 (prosody-configuration
18126 (modules-enabled (cons "groups" "mam" %default-modules-enabled))
18129 (int-component-configuration
18130 (hostname "conference.example.net")
18132 (mod-muc (mod-muc-configuration)))))
18135 (virtualhost-configuration
18136 (domain "example.net"))))))
18139 See below for details about @code{prosody-configuration}.
18143 By default, Prosody does not need much configuration. Only one
18144 @code{virtualhosts} field is needed: it specifies the domain you wish
18147 You can perform various sanity checks on the generated configuration
18148 with the @code{prosodyctl check} command.
18150 Prosodyctl will also help you to import certificates from the
18151 @code{letsencrypt} directory so that the @code{prosody} user can access
18152 them. See @url{https://prosody.im/doc/letsencrypt}.
18155 prosodyctl --root cert import /etc/letsencrypt/live
18158 The available configuration parameters follow. Each parameter
18159 definition is preceded by its type; for example, @samp{string-list foo}
18160 indicates that the @code{foo} parameter should be specified as a list of
18161 strings. Types starting with @code{maybe-} denote parameters that won't
18162 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
18164 There is also a way to specify the configuration as a string, if you
18165 have an old @code{prosody.cfg.lua} file that you want to port over from
18166 some other system; see the end for more details.
18168 The @code{file-object} type designates either a file-like object
18169 (@pxref{G-Expressions, file-like objects}) or a file name.
18171 @c The following documentation was initially generated by
18172 @c (generate-documentation) in (gnu services messaging). Manually maintained
18173 @c documentation is better, so we shouldn't hesitate to edit below as
18174 @c needed. However if the change you want to make to this documentation
18175 @c can be done in an automated way, it's probably easier to change
18176 @c (generate-documentation) than to make it below and have to deal with
18177 @c the churn as Prosody updates.
18179 Available @code{prosody-configuration} fields are:
18181 @deftypevr {@code{prosody-configuration} parameter} package prosody
18182 The Prosody package.
18185 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
18186 Location of the Prosody data storage directory. See
18187 @url{https://prosody.im/doc/configure}.
18188 Defaults to @samp{"/var/lib/prosody"}.
18191 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
18192 Additional plugin directories. They are searched in all the specified
18193 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
18194 Defaults to @samp{()}.
18197 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
18198 Every virtual host and component needs a certificate so that clients and
18199 servers can securely verify its identity. Prosody will automatically load
18200 certificates/keys from the directory specified here.
18201 Defaults to @samp{"/etc/prosody/certs"}.
18204 @deftypevr {@code{prosody-configuration} parameter} string-list admins
18205 This is a list of accounts that are admins for the server. Note that you
18206 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
18207 @url{https://prosody.im/doc/creating_accounts}.
18208 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
18209 Defaults to @samp{()}.
18212 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
18213 Enable use of libevent for better performance under high load. See
18214 @url{https://prosody.im/doc/libevent}.
18215 Defaults to @samp{#f}.
18218 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
18219 This is the list of modules Prosody will load on startup. It looks for
18220 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
18221 Documentation on modules can be found at:
18222 @url{https://prosody.im/doc/modules}.
18223 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
18226 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
18227 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
18228 should you want to disable them then add them to this list.
18229 Defaults to @samp{()}.
18232 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
18233 Path to a text file where the shared groups are defined. If this path is
18234 empty then @samp{mod_groups} does nothing. See
18235 @url{https://prosody.im/doc/modules/mod_groups}.
18236 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
18239 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
18240 Disable account creation by default, for security. See
18241 @url{https://prosody.im/doc/creating_accounts}.
18242 Defaults to @samp{#f}.
18245 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
18246 These are the SSL/TLS-related settings. Most of them are disabled so to
18247 use Prosody's defaults. If you do not completely understand these options, do
18248 not add them to your config, it is easy to lower the security of your server
18249 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
18251 Available @code{ssl-configuration} fields are:
18253 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
18254 This determines what handshake to use.
18257 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
18258 Path to your private key file.
18261 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
18262 Path to your certificate file.
18265 @deftypevr {@code{ssl-configuration} parameter} file-object capath
18266 Path to directory containing root certificates that you wish Prosody to
18267 trust when verifying the certificates of remote servers.
18268 Defaults to @samp{"/etc/ssl/certs"}.
18271 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
18272 Path to a file containing root certificates that you wish Prosody to trust.
18273 Similar to @code{capath} but with all certificates concatenated together.
18276 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
18277 A list of verification options (these mostly map to OpenSSL's
18278 @code{set_verify()} flags).
18281 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
18282 A list of general options relating to SSL/TLS. These map to OpenSSL's
18283 @code{set_options()}. For a full list of options available in LuaSec, see the
18287 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
18288 How long a chain of certificate authorities to check when looking for a
18289 trusted root certificate.
18292 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
18293 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
18294 clients, and in what order.
18297 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
18298 A path to a file containing parameters for Diffie-Hellman key exchange. You
18299 can create such a file with:
18300 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
18303 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
18304 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
18305 @samp{"secp384r1"}.
18308 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
18309 A list of "extra" verification options.
18312 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
18313 Password for encrypted private keys.
18318 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
18319 Whether to force all client-to-server connections to be encrypted or not.
18320 See @url{https://prosody.im/doc/modules/mod_tls}.
18321 Defaults to @samp{#f}.
18324 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
18325 Set of mechanisms that will never be offered. See
18326 @url{https://prosody.im/doc/modules/mod_saslauth}.
18327 Defaults to @samp{("DIGEST-MD5")}.
18330 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
18331 Whether to force all server-to-server connections to be encrypted or not.
18332 See @url{https://prosody.im/doc/modules/mod_tls}.
18333 Defaults to @samp{#f}.
18336 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
18337 Whether to require encryption and certificate authentication. This
18338 provides ideal security, but requires servers you communicate with to support
18339 encryption AND present valid, trusted certificates. See
18340 @url{https://prosody.im/doc/s2s#security}.
18341 Defaults to @samp{#f}.
18344 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
18345 Many servers don't support encryption or have invalid or self-signed
18346 certificates. You can list domains here that will not be required to
18347 authenticate using certificates. They will be authenticated using DNS. See
18348 @url{https://prosody.im/doc/s2s#security}.
18349 Defaults to @samp{()}.
18352 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
18353 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
18354 valid certificates for some domains by specifying a list here. See
18355 @url{https://prosody.im/doc/s2s#security}.
18356 Defaults to @samp{()}.
18359 @deftypevr {@code{prosody-configuration} parameter} string authentication
18360 Select the authentication backend to use. The default provider stores
18361 passwords in plaintext and uses Prosody's configured data storage to store the
18362 authentication data. If you do not trust your server please see
18363 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
18364 about using the hashed backend. See also
18365 @url{https://prosody.im/doc/authentication}
18366 Defaults to @samp{"internal_plain"}.
18369 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
18370 Set logging options. Advanced logging configuration is not yet supported
18371 by the Prosody service. See @url{https://prosody.im/doc/logging}.
18372 Defaults to @samp{"*syslog"}.
18375 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
18376 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
18377 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
18380 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
18381 Maximum allowed size of the HTTP body (in bytes).
18384 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
18385 Some modules expose their own URL in various ways. This URL is built
18386 from the protocol, host and port used. If Prosody sits behind a proxy, the
18387 public URL will be @code{http-external-url} instead. See
18388 @url{https://prosody.im/doc/http#external_url}.
18391 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
18392 A host in Prosody is a domain on which user accounts can be created. For
18393 example if you want your users to have addresses like
18394 @samp{"john.smith@@example.com"} then you need to add a host
18395 @samp{"example.com"}. All options in this list will apply only to this host.
18397 Note: the name "virtual" host is used in configuration to avoid confusion with
18398 the actual physical host that Prosody is installed on. A single Prosody
18399 instance can serve many domains, each one defined as a VirtualHost entry in
18400 Prosody's configuration. Conversely a server that hosts a single domain would
18401 have just one VirtualHost entry.
18403 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
18405 Available @code{virtualhost-configuration} fields are:
18407 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:
18408 @deftypevr {@code{virtualhost-configuration} parameter} string domain
18409 Domain you wish Prosody to serve.
18414 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
18415 Components are extra services on a server which are available to clients,
18416 usually on a subdomain of the main server (such as
18417 @samp{"mycomponent.example.com"}). Example components might be chatroom
18418 servers, user directories, or gateways to other protocols.
18420 Internal components are implemented with Prosody-specific plugins. To add an
18421 internal component, you simply fill the hostname field, and the plugin you wish
18422 to use for the component.
18424 See @url{https://prosody.im/doc/components}.
18425 Defaults to @samp{()}.
18427 Available @code{int-component-configuration} fields are:
18429 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:
18430 @deftypevr {@code{int-component-configuration} parameter} string hostname
18431 Hostname of the component.
18434 @deftypevr {@code{int-component-configuration} parameter} string plugin
18435 Plugin you wish to use for the component.
18438 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
18439 Multi-user chat (MUC) is Prosody's module for allowing you to create
18440 hosted chatrooms/conferences for XMPP users.
18442 General information on setting up and using multi-user chatrooms can be found
18443 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
18444 which you should read if you are new to XMPP chatrooms.
18446 See also @url{https://prosody.im/doc/modules/mod_muc}.
18448 Available @code{mod-muc-configuration} fields are:
18450 @deftypevr {@code{mod-muc-configuration} parameter} string name
18451 The name to return in service discovery responses.
18452 Defaults to @samp{"Prosody Chatrooms"}.
18455 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
18456 If @samp{#t}, this will only allow admins to create new chatrooms.
18457 Otherwise anyone can create a room. The value @samp{"local"} restricts room
18458 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
18459 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
18460 restricts to service administrators only.
18461 Defaults to @samp{#f}.
18464 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
18465 Maximum number of history messages that will be sent to the member that has
18466 just joined the room.
18467 Defaults to @samp{20}.
18474 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
18475 External components use XEP-0114, which most standalone components
18476 support. To add an external component, you simply fill the hostname field. See
18477 @url{https://prosody.im/doc/components}.
18478 Defaults to @samp{()}.
18480 Available @code{ext-component-configuration} fields are:
18482 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:
18483 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
18484 Password which the component will use to log in.
18487 @deftypevr {@code{ext-component-configuration} parameter} string hostname
18488 Hostname of the component.
18493 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
18494 Port(s) Prosody listens on for component connections.
18495 Defaults to @samp{(5347)}.
18498 @deftypevr {@code{prosody-configuration} parameter} string component-interface
18499 Interface Prosody listens on for component connections.
18500 Defaults to @samp{"127.0.0.1"}.
18503 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
18504 Raw content that will be added to the configuration file.
18507 It could be that you just want to get a @code{prosody.cfg.lua}
18508 up and running. In that case, you can pass an
18509 @code{opaque-prosody-configuration} record as the value of
18510 @code{prosody-service-type}. As its name indicates, an opaque configuration
18511 does not have easy reflective capabilities.
18512 Available @code{opaque-prosody-configuration} fields are:
18514 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
18515 The prosody package.
18518 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
18519 The contents of the @code{prosody.cfg.lua} to use.
18522 For example, if your @code{prosody.cfg.lua} is just the empty
18523 string, you could instantiate a prosody service like this:
18526 (service prosody-service-type
18527 (opaque-prosody-configuration
18528 (prosody.cfg.lua "")))
18531 @c end of Prosody auto-generated documentation
18533 @subsubheading BitlBee Service
18535 @cindex IRC (Internet Relay Chat)
18536 @cindex IRC gateway
18537 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
18538 interface to a variety of messaging protocols such as XMPP.
18540 @defvr {Scheme Variable} bitlbee-service-type
18541 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
18542 gateway daemon. Its value is a @code{bitlbee-configuration} (see
18545 To have BitlBee listen on port 6667 on localhost, add this line to your
18549 (service bitlbee-service-type)
18553 @deftp {Data Type} bitlbee-configuration
18554 This is the configuration for BitlBee, with the following fields:
18557 @item @code{interface} (default: @code{"127.0.0.1"})
18558 @itemx @code{port} (default: @code{6667})
18559 Listen on the network interface corresponding to the IP address
18560 specified in @var{interface}, on @var{port}.
18562 When @var{interface} is @code{127.0.0.1}, only local clients can
18563 connect; when it is @code{0.0.0.0}, connections can come from any
18564 networking interface.
18566 @item @code{bitlbee} (default: @code{bitlbee})
18567 The BitlBee package to use.
18569 @item @code{plugins} (default: @code{'()})
18570 List of plugin packages to use---e.g., @code{bitlbee-discord}.
18572 @item @code{extra-settings} (default: @code{""})
18573 Configuration snippet added as-is to the BitlBee configuration file.
18577 @subsubheading Quassel Service
18579 @cindex IRC (Internet Relay Chat)
18580 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
18581 meaning that one or more clients can attach to and detach from the
18584 @defvr {Scheme Variable} quassel-service-type
18585 This is the service type for the @url{https://quassel-irc.org/,Quassel}
18586 IRC backend daemon. Its value is a @code{quassel-configuration}
18590 @deftp {Data Type} quassel-configuration
18591 This is the configuration for Quassel, with the following fields:
18594 @item @code{quassel} (default: @code{quassel})
18595 The Quassel package to use.
18597 @item @code{interface} (default: @code{"::,0.0.0.0"})
18598 @item @code{port} (default: @code{4242})
18599 Listen on the network interface(s) corresponding to the IPv4 or IPv6
18600 interfaces specified in the comma delimited @var{interface}, on
18603 @item @code{loglevel} (default: @code{"Info"})
18604 The level of logging desired. Accepted values are Debug, Info, Warning
18609 @node Telephony Services
18610 @subsection Telephony Services
18612 @cindex Murmur (VoIP server)
18613 @cindex VoIP server
18614 This section describes how to set up and run a Murmur server. Murmur is
18615 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
18618 @deftp {Data Type} murmur-configuration
18619 The service type for the Murmur server. An example configuration can
18623 (service murmur-service-type
18624 (murmur-configuration
18626 "Welcome to this Mumble server running on Guix!")
18627 (cert-required? #t) ;disallow text password logins
18628 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
18629 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
18632 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
18633 password with the command that is printed during the activation phase.
18635 It is recommended to register a normal Mumble user account
18636 and grant it admin or moderator rights.
18637 You can use the @code{mumble} client to
18638 login as new normal user, register yourself, and log out.
18639 For the next step login with the name @code{SuperUser} use
18640 the @code{SuperUser} password that you set previously,
18641 and grant your newly registered mumble user administrator or moderator
18642 rights and create some channels.
18644 Available @code{murmur-configuration} fields are:
18647 @item @code{package} (default: @code{mumble})
18648 Package that contains @code{bin/murmurd}.
18650 @item @code{user} (default: @code{"murmur"})
18651 User who will run the Murmur server.
18653 @item @code{group} (default: @code{"murmur"})
18654 Group of the user who will run the murmur server.
18656 @item @code{port} (default: @code{64738})
18657 Port on which the server will listen.
18659 @item @code{welcome-text} (default: @code{""})
18660 Welcome text sent to clients when they connect.
18662 @item @code{server-password} (default: @code{""})
18663 Password the clients have to enter in order to connect.
18665 @item @code{max-users} (default: @code{100})
18666 Maximum of users that can be connected to the server at once.
18668 @item @code{max-user-bandwidth} (default: @code{#f})
18669 Maximum voice traffic a user can send per second.
18671 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
18672 File name of the sqlite database.
18673 The service's user will become the owner of the directory.
18675 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
18676 File name of the log file.
18677 The service's user will become the owner of the directory.
18679 @item @code{autoban-attempts} (default: @code{10})
18680 Maximum number of logins a user can make in @code{autoban-timeframe}
18681 without getting auto banned for @code{autoban-time}.
18683 @item @code{autoban-timeframe} (default: @code{120})
18684 Timeframe for autoban in seconds.
18686 @item @code{autoban-time} (default: @code{300})
18687 Amount of time in seconds for which a client gets banned
18688 when violating the autoban limits.
18690 @item @code{opus-threshold} (default: @code{100})
18691 Percentage of clients that need to support opus
18692 before switching over to opus audio codec.
18694 @item @code{channel-nesting-limit} (default: @code{10})
18695 How deep channels can be nested at maximum.
18697 @item @code{channelname-regex} (default: @code{#f})
18698 A string in form of a Qt regular expression that channel names must conform to.
18700 @item @code{username-regex} (default: @code{#f})
18701 A string in form of a Qt regular expression that user names must conform to.
18703 @item @code{text-message-length} (default: @code{5000})
18704 Maximum size in bytes that a user can send in one text chat message.
18706 @item @code{image-message-length} (default: @code{(* 128 1024)})
18707 Maximum size in bytes that a user can send in one image message.
18709 @item @code{cert-required?} (default: @code{#f})
18710 If it is set to @code{#t} clients that use weak password authentication
18711 will not be accepted. Users must have completed the certificate wizard to join.
18713 @item @code{remember-channel?} (default: @code{#f})
18714 Should murmur remember the last channel each user was in when they disconnected
18715 and put them into the remembered channel when they rejoin.
18717 @item @code{allow-html?} (default: @code{#f})
18718 Should html be allowed in text messages, user comments, and channel descriptions.
18720 @item @code{allow-ping?} (default: @code{#f})
18721 Setting to true exposes the current user count, the maximum user count, and
18722 the server's maximum bandwidth per client to unauthenticated users. In the
18723 Mumble client, this information is shown in the Connect dialog.
18725 Disabling this setting will prevent public listing of the server.
18727 @item @code{bonjour?} (default: @code{#f})
18728 Should the server advertise itself in the local network through the bonjour protocol.
18730 @item @code{send-version?} (default: @code{#f})
18731 Should the murmur server version be exposed in ping requests.
18733 @item @code{log-days} (default: @code{31})
18734 Murmur also stores logs in the database, which are accessible via RPC.
18735 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
18736 or -1 to disable logging to the database.
18738 @item @code{obfuscate-ips?} (default: @code{#t})
18739 Should logged ips be obfuscated to protect the privacy of users.
18741 @item @code{ssl-cert} (default: @code{#f})
18742 File name of the SSL/TLS certificate used for encrypted connections.
18745 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
18747 @item @code{ssl-key} (default: @code{#f})
18748 Filepath to the ssl private key used for encrypted connections.
18750 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
18753 @item @code{ssl-dh-params} (default: @code{#f})
18754 File name of a PEM-encoded file with Diffie-Hellman parameters
18755 for the SSL/TLS encryption. Alternatively you set it to
18756 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
18757 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
18759 @item @code{ssl-ciphers} (default: @code{#f})
18760 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
18763 This option is specified using
18764 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
18765 OpenSSL cipher list notation}.
18767 It is recommended that you try your cipher string using 'openssl ciphers <string>'
18768 before setting it here, to get a feel for which cipher suites you will get.
18769 After setting this option, it is recommend that you inspect your Murmur log
18770 to ensure that Murmur is using the cipher suites that you expected it to.
18772 Note: Changing this option may impact the backwards compatibility of your
18773 Murmur server, and can remove the ability for older Mumble clients to be able
18776 @item @code{public-registration} (default: @code{#f})
18777 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
18779 You can optionally register your server in the public server list that the
18780 @code{mumble} client shows on startup.
18781 You cannot register your server if you have set a @code{server-password},
18782 or set @code{allow-ping} to @code{#f}.
18784 It might take a few hours until it shows up in the public list.
18786 @item @code{file} (default: @code{#f})
18787 Optional alternative override for this configuration.
18791 @deftp {Data Type} murmur-public-registration-configuration
18792 Configuration for public registration of a murmur service.
18796 This is a display name for your server. Not to be confused with the hostname.
18798 @item @code{password}
18799 A password to identify your registration.
18800 Subsequent updates will need the same password. Don't lose your password.
18803 This should be a @code{http://} or @code{https://} link to your web
18806 @item @code{hostname} (default: @code{#f})
18807 By default your server will be listed by its IP address.
18808 If it is set your server will be linked by this host name instead.
18814 @node Monitoring Services
18815 @subsection Monitoring Services
18817 @subsubheading Tailon Service
18819 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
18820 viewing and searching log files.
18822 The following example will configure the service with default values.
18823 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
18826 (service tailon-service-type)
18829 The following example customises more of the Tailon configuration,
18830 adding @command{sed} to the list of allowed commands.
18833 (service tailon-service-type
18834 (tailon-configuration
18836 (tailon-configuration-file
18837 (allowed-commands '("tail" "grep" "awk" "sed"))))))
18841 @deftp {Data Type} tailon-configuration
18842 Data type representing the configuration of Tailon.
18843 This type has the following parameters:
18846 @item @code{config-file} (default: @code{(tailon-configuration-file)})
18847 The configuration file to use for Tailon. This can be set to a
18848 @dfn{tailon-configuration-file} record value, or any gexp
18849 (@pxref{G-Expressions}).
18851 For example, to instead use a local file, the @code{local-file} function
18855 (service tailon-service-type
18856 (tailon-configuration
18857 (config-file (local-file "./my-tailon.conf"))))
18860 @item @code{package} (default: @code{tailon})
18861 The tailon package to use.
18866 @deftp {Data Type} tailon-configuration-file
18867 Data type representing the configuration options for Tailon.
18868 This type has the following parameters:
18871 @item @code{files} (default: @code{(list "/var/log")})
18872 List of files to display. The list can include strings for a single file
18873 or directory, or a list, where the first item is the name of a
18874 subsection, and the remaining items are the files or directories in that
18877 @item @code{bind} (default: @code{"localhost:8080"})
18878 Address and port to which Tailon should bind on.
18880 @item @code{relative-root} (default: @code{#f})
18881 URL path to use for Tailon, set to @code{#f} to not use a path.
18883 @item @code{allow-transfers?} (default: @code{#t})
18884 Allow downloading the log files in the web interface.
18886 @item @code{follow-names?} (default: @code{#t})
18887 Allow tailing of not-yet existent files.
18889 @item @code{tail-lines} (default: @code{200})
18890 Number of lines to read initially from each file.
18892 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
18893 Commands to allow running. By default, @code{sed} is disabled.
18895 @item @code{debug?} (default: @code{#f})
18896 Set @code{debug?} to @code{#t} to show debug messages.
18898 @item @code{wrap-lines} (default: @code{#t})
18899 Initial line wrapping state in the web interface. Set to @code{#t} to
18900 initially wrap lines (the default), or to @code{#f} to initially not
18903 @item @code{http-auth} (default: @code{#f})
18904 HTTP authentication type to use. Set to @code{#f} to disable
18905 authentication (the default). Supported values are @code{"digest"} or
18908 @item @code{users} (default: @code{#f})
18909 If HTTP authentication is enabled (see @code{http-auth}), access will be
18910 restricted to the credentials provided here. To configure users, use a
18911 list of pairs, where the first element of the pair is the username, and
18912 the 2nd element of the pair is the password.
18915 (tailon-configuration-file
18916 (http-auth "basic")
18917 (users '(("user1" . "password1")
18918 ("user2" . "password2"))))
18925 @subsubheading Darkstat Service
18927 Darkstat is a packet sniffer that captures network traffic, calculates
18928 statistics about usage, and serves reports over HTTP.
18930 @defvar {Scheme Variable} darkstat-service-type
18931 This is the service type for the
18932 @uref{https://unix4lyfe.org/darkstat/, darkstat}
18933 service, its value must be a @code{darkstat-configuration} record as in
18937 (service darkstat-service-type
18938 (darkstat-configuration
18939 (interface "eno1")))
18943 @deftp {Data Type} darkstat-configuration
18944 Data type representing the configuration of @command{darkstat}.
18947 @item @code{package} (default: @code{darkstat})
18948 The darkstat package to use.
18950 @item @code{interface}
18951 Capture traffic on the specified network interface.
18953 @item @code{port} (default: @code{"667"})
18954 Bind the web interface to the specified port.
18956 @item @code{bind-address} (default: @code{"127.0.0.1"})
18957 Bind the web interface to the specified address.
18959 @item @code{base} (default: @code{"/"})
18960 Specify the path of the base URL. This can be useful if
18961 @command{darkstat} is accessed via a reverse proxy.
18966 @subsubheading Prometheus Node Exporter Service
18968 @cindex prometheus-node-exporter
18969 The Prometheus ``node exporter'' makes hardware and operating system statistics
18970 provided by the Linux kernel available for the Prometheus monitoring system.
18971 This service should be deployed on all physical nodes and virtual machines,
18972 where monitoring these statistics is desirable.
18974 @defvar {Scheme variable} prometheus-node-exporter-service-type
18975 This is the service type for the
18976 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
18977 service, its value must be a @code{prometheus-node-exporter-configuration}
18978 record as in this example:
18981 (service prometheus-node-exporter-service-type
18982 (prometheus-node-exporter-configuration
18983 (web-listen-address ":9100")))
18987 @deftp {Data Type} prometheus-node-exporter-configuration
18988 Data type representing the configuration of @command{node_exporter}.
18991 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
18992 The prometheus-node-exporter package to use.
18994 @item @code{web-listen-address} (default: @code{":9100"})
18995 Bind the web interface to the specified address.
19000 @subsubheading Zabbix server
19001 @cindex zabbix zabbix-server
19002 Zabbix provides monitoring metrics, among others network utilization, CPU load
19003 and disk space consumption:
19006 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
19007 @item Auto-discovery of servers and network devices and interfaces.
19008 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
19009 @item Distributed monitoring with centralized web administration.
19010 @item Native high performance agents.
19011 @item SLA, and ITIL KPI metrics on reporting.
19012 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
19013 @item Remote command execution through Zabbix proxies.
19016 @c %start of fragment
19018 Available @code{zabbix-server-configuration} fields are:
19020 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
19021 The zabbix-server package.
19025 @deftypevr {@code{zabbix-server-configuration} parameter} string user
19026 User who will run the Zabbix server.
19028 Defaults to @samp{"zabbix"}.
19032 @deftypevr {@code{zabbix-server-configuration} parameter} group group
19033 Group who will run the Zabbix server.
19035 Defaults to @samp{"zabbix"}.
19039 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
19040 Database host name.
19042 Defaults to @samp{"127.0.0.1"}.
19046 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
19049 Defaults to @samp{"zabbix"}.
19053 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
19056 Defaults to @samp{"zabbix"}.
19060 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
19061 Database password. Please, use @code{include-files} with
19062 @code{DBPassword=SECRET} inside a specified file instead.
19064 Defaults to @samp{""}.
19068 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
19071 Defaults to @samp{5432}.
19075 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
19076 Specifies where log messages are written to:
19080 @code{system} - syslog.
19083 @code{file} - file specified with @code{log-file} parameter.
19086 @code{console} - standard output.
19090 Defaults to @samp{""}.
19094 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
19095 Log file name for @code{log-type} @code{file} parameter.
19097 Defaults to @samp{"/var/log/zabbix/server.log"}.
19101 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
19104 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
19108 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
19109 The location of certificate authority (CA) files for SSL server
19110 certificate verification.
19112 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
19116 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
19117 Location of SSL client certificates.
19119 Defaults to @samp{"/etc/ssl/certs"}.
19123 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
19124 Extra options will be appended to Zabbix server configuration file.
19126 Defaults to @samp{""}.
19130 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
19131 You may include individual files or all files in a directory in the
19132 configuration file.
19134 Defaults to @samp{()}.
19138 @c %end of fragment
19140 @subsubheading Zabbix agent
19141 @cindex zabbix zabbix-agent
19143 Zabbix agent gathers information for Zabbix server.
19145 @c %start of fragment
19147 Available @code{zabbix-agent-configuration} fields are:
19149 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
19150 The zabbix-agent package.
19154 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
19155 User who will run the Zabbix agent.
19157 Defaults to @samp{"zabbix"}.
19161 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
19162 Group who will run the Zabbix agent.
19164 Defaults to @samp{"zabbix"}.
19168 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
19169 Unique, case sensitive hostname which is required for active checks and
19170 must match hostname as configured on the server.
19172 Defaults to @samp{"Zabbix server"}.
19176 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
19177 Specifies where log messages are written to:
19181 @code{system} - syslog.
19184 @code{file} - file specified with @code{log-file} parameter.
19187 @code{console} - standard output.
19191 Defaults to @samp{""}.
19195 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
19196 Log file name for @code{log-type} @code{file} parameter.
19198 Defaults to @samp{"/var/log/zabbix/agent.log"}.
19202 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
19205 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
19209 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
19210 List of IP addresses, optionally in CIDR notation, or hostnames of
19211 Zabbix servers and Zabbix proxies. Incoming connections will be
19212 accepted only from the hosts listed here.
19214 Defaults to @samp{("127.0.0.1")}.
19218 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
19219 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
19220 proxies for active checks. If port is not specified, default port is
19221 used. If this parameter is not specified, active checks are disabled.
19223 Defaults to @samp{("127.0.0.1")}.
19227 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
19228 Extra options will be appended to Zabbix server configuration file.
19230 Defaults to @samp{""}.
19234 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
19235 You may include individual files or all files in a directory in the
19236 configuration file.
19238 Defaults to @samp{()}.
19242 @c %end of fragment
19244 @subsubheading Zabbix front-end
19245 @cindex zabbix zabbix-front-end
19247 This service provides a WEB interface to Zabbix server.
19249 @c %start of fragment
19251 Available @code{zabbix-front-end-configuration} fields are:
19253 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
19254 NGINX configuration.
19258 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
19259 Database host name.
19261 Defaults to @samp{"localhost"}.
19265 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
19268 Defaults to @samp{5432}.
19272 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
19275 Defaults to @samp{"zabbix"}.
19279 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
19282 Defaults to @samp{"zabbix"}.
19286 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
19287 Database password. Please, use @code{db-secret-file} instead.
19289 Defaults to @samp{""}.
19293 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
19294 Secret file which will be appended to @file{zabbix.conf.php} file. This
19295 file contains credentials for use by Zabbix front-end. You are expected
19296 to create it manually.
19298 Defaults to @samp{""}.
19302 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
19303 Zabbix server hostname.
19305 Defaults to @samp{"localhost"}.
19309 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
19310 Zabbix server port.
19312 Defaults to @samp{10051}.
19317 @c %end of fragment
19319 @node Kerberos Services
19320 @subsection Kerberos Services
19323 The @code{(gnu services kerberos)} module provides services relating to
19324 the authentication protocol @dfn{Kerberos}.
19326 @subsubheading Krb5 Service
19328 Programs using a Kerberos client library normally
19329 expect a configuration file in @file{/etc/krb5.conf}.
19330 This service generates such a file from a definition provided in the
19331 operating system declaration.
19332 It does not cause any daemon to be started.
19334 No ``keytab'' files are provided by this service---you must explicitly create them.
19335 This service is known to work with the MIT client library, @code{mit-krb5}.
19336 Other implementations have not been tested.
19338 @defvr {Scheme Variable} krb5-service-type
19339 A service type for Kerberos 5 clients.
19343 Here is an example of its use:
19345 (service krb5-service-type
19346 (krb5-configuration
19347 (default-realm "EXAMPLE.COM")
19348 (allow-weak-crypto? #t)
19351 (name "EXAMPLE.COM")
19352 (admin-server "groucho.example.com")
19353 (kdc "karl.example.com"))
19356 (admin-server "kerb-admin.argrx.edu")
19357 (kdc "keys.argrx.edu"))))))
19361 This example provides a Kerberos@tie{}5 client configuration which:
19363 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
19364 of which have distinct administration servers and key distribution centers;
19365 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
19366 specified by clients;
19367 @item Accepts services which only support encryption types known to be weak.
19370 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
19371 Only the most commonly used ones are described here.
19372 For a full list, and more detailed explanation of each, see the MIT
19373 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
19377 @deftp {Data Type} krb5-realm
19378 @cindex realm, kerberos
19381 This field is a string identifying the name of the realm.
19382 A common convention is to use the fully qualified DNS name of your organization,
19383 converted to upper case.
19385 @item @code{admin-server}
19386 This field is a string identifying the host where the administration server is
19390 This field is a string identifying the key distribution center
19395 @deftp {Data Type} krb5-configuration
19398 @item @code{allow-weak-crypto?} (default: @code{#f})
19399 If this flag is @code{#t} then services which only offer encryption algorithms
19400 known to be weak will be accepted.
19402 @item @code{default-realm} (default: @code{#f})
19403 This field should be a string identifying the default Kerberos
19404 realm for the client.
19405 You should set this field to the name of your Kerberos realm.
19406 If this value is @code{#f}
19407 then a realm must be specified with every Kerberos principal when invoking programs
19408 such as @command{kinit}.
19410 @item @code{realms}
19411 This should be a non-empty list of @code{krb5-realm} objects, which clients may
19413 Normally, one of them will have a @code{name} field matching the @code{default-realm}
19419 @subsubheading PAM krb5 Service
19422 The @code{pam-krb5} service allows for login authentication and password
19423 management via Kerberos.
19424 You will need this service if you want PAM enabled applications to authenticate
19425 users using Kerberos.
19427 @defvr {Scheme Variable} pam-krb5-service-type
19428 A service type for the Kerberos 5 PAM module.
19431 @deftp {Data Type} pam-krb5-configuration
19432 Data type representing the configuration of the Kerberos 5 PAM module.
19433 This type has the following parameters:
19435 @item @code{pam-krb5} (default: @code{pam-krb5})
19436 The pam-krb5 package to use.
19438 @item @code{minimum-uid} (default: @code{1000})
19439 The smallest user ID for which Kerberos authentications should be attempted.
19440 Local accounts with lower values will silently fail to authenticate.
19445 @node LDAP Services
19446 @subsection LDAP Services
19448 @cindex nslcd, LDAP service
19450 The @code{(gnu services authentication)} module provides the
19451 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
19452 server. In addition to configuring the service itself, you may want to add
19453 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
19454 Switch} for detailed information.
19456 Here is a simple operating system declaration with a default configuration of
19457 the @code{nslcd-service-type} and a Name Service Switch configuration that
19458 consults the @code{ldap} name service last:
19461 (use-service-modules authentication)
19462 (use-modules (gnu system nss))
19468 (service nslcd-service-type)
19469 (service dhcp-client-service-type)
19471 (name-service-switch
19472 (let ((services (list (name-service (name "db"))
19473 (name-service (name "files"))
19474 (name-service (name "ldap")))))
19475 (name-service-switch
19476 (inherit %mdns-host-lookup-nss)
19477 (password services)
19480 (netgroup services)
19481 (gshadow services)))))
19484 @c %start of generated documentation for nslcd-configuration
19486 Available @code{nslcd-configuration} fields are:
19488 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
19489 The @code{nss-pam-ldapd} package to use.
19493 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
19494 The number of threads to start that can handle requests and perform LDAP
19495 queries. Each thread opens a separate connection to the LDAP server.
19496 The default is to start 5 threads.
19498 Defaults to @samp{disabled}.
19502 @deftypevr {@code{nslcd-configuration} parameter} string uid
19503 This specifies the user id with which the daemon should be run.
19505 Defaults to @samp{"nslcd"}.
19509 @deftypevr {@code{nslcd-configuration} parameter} string gid
19510 This specifies the group id with which the daemon should be run.
19512 Defaults to @samp{"nslcd"}.
19516 @deftypevr {@code{nslcd-configuration} parameter} log-option log
19517 This option controls the way logging is done via a list containing
19518 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
19519 or "syslog", or an absolute file name. The LEVEL argument is optional
19520 and specifies the log level. The log level may be one of the following
19521 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
19522 messages with the specified log level or higher are logged.
19524 Defaults to @samp{("/var/log/nslcd" info)}.
19528 @deftypevr {@code{nslcd-configuration} parameter} list uri
19529 The list of LDAP server URIs. Normally, only the first server will be
19530 used with the following servers as fall-back.
19532 Defaults to @samp{("ldap://localhost:389/")}.
19536 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
19537 The version of the LDAP protocol to use. The default is to use the
19538 maximum version supported by the LDAP library.
19540 Defaults to @samp{disabled}.
19544 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
19545 Specifies the distinguished name with which to bind to the directory
19546 server for lookups. The default is to bind anonymously.
19548 Defaults to @samp{disabled}.
19552 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
19553 Specifies the credentials with which to bind. This option is only
19554 applicable when used with binddn.
19556 Defaults to @samp{disabled}.
19560 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
19561 Specifies the distinguished name to use when the root user tries to
19562 modify a user's password using the PAM module.
19564 Defaults to @samp{disabled}.
19568 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
19569 Specifies the credentials with which to bind if the root user tries to
19570 change a user's password. This option is only applicable when used with
19573 Defaults to @samp{disabled}.
19577 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
19578 Specifies the SASL mechanism to be used when performing SASL
19581 Defaults to @samp{disabled}.
19585 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
19586 Specifies the SASL realm to be used when performing SASL authentication.
19588 Defaults to @samp{disabled}.
19592 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
19593 Specifies the authentication identity to be used when performing SASL
19596 Defaults to @samp{disabled}.
19600 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
19601 Specifies the authorization identity to be used when performing SASL
19604 Defaults to @samp{disabled}.
19608 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
19609 Determines whether the LDAP server host name should be canonicalised. If
19610 this is enabled the LDAP library will do a reverse host name lookup. By
19611 default, it is left up to the LDAP library whether this check is
19614 Defaults to @samp{disabled}.
19618 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
19619 Set the name for the GSS-API Kerberos credentials cache.
19621 Defaults to @samp{disabled}.
19625 @deftypevr {@code{nslcd-configuration} parameter} string base
19626 The directory search base.
19628 Defaults to @samp{"dc=example,dc=com"}.
19632 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
19633 Specifies the search scope (subtree, onelevel, base or children). The
19634 default scope is subtree; base scope is almost never useful for name
19635 service lookups; children scope is not supported on all servers.
19637 Defaults to @samp{(subtree)}.
19641 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
19642 Specifies the policy for dereferencing aliases. The default policy is
19643 to never dereference aliases.
19645 Defaults to @samp{disabled}.
19649 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
19650 Specifies whether automatic referral chasing should be enabled. The
19651 default behaviour is to chase referrals.
19653 Defaults to @samp{disabled}.
19657 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
19658 This option allows for custom attributes to be looked up instead of the
19659 default RFC 2307 attributes. It is a list of maps, each consisting of
19660 the name of a map, the RFC 2307 attribute to match and the query
19661 expression for the attribute as it is available in the directory.
19663 Defaults to @samp{()}.
19667 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
19668 A list of filters consisting of the name of a map to which the filter
19669 applies and an LDAP search filter expression.
19671 Defaults to @samp{()}.
19675 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
19676 Specifies the time limit in seconds to use when connecting to the
19677 directory server. The default value is 10 seconds.
19679 Defaults to @samp{disabled}.
19683 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
19684 Specifies the time limit (in seconds) to wait for a response from the
19685 LDAP server. A value of zero, which is the default, is to wait
19686 indefinitely for searches to be completed.
19688 Defaults to @samp{disabled}.
19692 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
19693 Specifies the period if inactivity (in seconds) after which the con‐
19694 nection to the LDAP server will be closed. The default is not to time
19697 Defaults to @samp{disabled}.
19701 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
19702 Specifies the number of seconds to sleep when connecting to all LDAP
19703 servers fails. By default one second is waited between the first
19704 failure and the first retry.
19706 Defaults to @samp{disabled}.
19710 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
19711 Specifies the time after which the LDAP server is considered to be
19712 permanently unavailable. Once this time is reached retries will be done
19713 only once per this time period. The default value is 10 seconds.
19715 Defaults to @samp{disabled}.
19719 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
19720 Specifies whether to use SSL/TLS or not (the default is not to). If
19721 'start-tls is specified then StartTLS is used rather than raw LDAP over
19724 Defaults to @samp{disabled}.
19728 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
19729 Specifies what checks to perform on a server-supplied certificate. The
19730 meaning of the values is described in the ldap.conf(5) manual page.
19732 Defaults to @samp{disabled}.
19736 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
19737 Specifies the directory containing X.509 certificates for peer authen‐
19738 tication. This parameter is ignored when using GnuTLS.
19740 Defaults to @samp{disabled}.
19744 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
19745 Specifies the path to the X.509 certificate for peer authentication.
19747 Defaults to @samp{disabled}.
19751 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
19752 Specifies the path to an entropy source. This parameter is ignored when
19755 Defaults to @samp{disabled}.
19759 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
19760 Specifies the ciphers to use for TLS as a string.
19762 Defaults to @samp{disabled}.
19766 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
19767 Specifies the path to the file containing the local certificate for
19768 client TLS authentication.
19770 Defaults to @samp{disabled}.
19774 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
19775 Specifies the path to the file containing the private key for client TLS
19778 Defaults to @samp{disabled}.
19782 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
19783 Set this to a number greater than 0 to request paged results from the
19784 LDAP server in accordance with RFC2696. The default (0) is to not
19785 request paged results.
19787 Defaults to @samp{disabled}.
19791 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
19792 This option prevents group membership lookups through LDAP for the
19793 specified users. Alternatively, the value 'all-local may be used. With
19794 that value nslcd builds a full list of non-LDAP users on startup.
19796 Defaults to @samp{disabled}.
19800 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
19801 This option ensures that LDAP users with a numeric user id lower than
19802 the specified value are ignored.
19804 Defaults to @samp{disabled}.
19808 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
19809 This option specifies an offset that is added to all LDAP numeric user
19810 ids. This can be used to avoid user id collisions with local users.
19812 Defaults to @samp{disabled}.
19816 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
19817 This option specifies an offset that is added to all LDAP numeric group
19818 ids. This can be used to avoid user id collisions with local groups.
19820 Defaults to @samp{disabled}.
19824 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
19825 If this option is set, the member attribute of a group may point to
19826 another group. Members of nested groups are also returned in the higher
19827 level group and parent groups are returned when finding groups for a
19828 specific user. The default is not to perform extra searches for nested
19831 Defaults to @samp{disabled}.
19835 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
19836 If this option is set, the group member list is not retrieved when
19837 looking up groups. Lookups for finding which groups a user belongs to
19838 will remain functional so the user will likely still get the correct
19839 groups assigned on login.
19841 Defaults to @samp{disabled}.
19845 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
19846 If this option is set, functions which cause all user/group entries to
19847 be loaded from the directory will not succeed in doing so. This can
19848 dramatically reduce LDAP server load in situations where there are a
19849 great number of users and/or groups. This option is not recommended for
19850 most configurations.
19852 Defaults to @samp{disabled}.
19856 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
19857 This option can be used to specify how user and group names are verified
19858 within the system. This pattern is used to check all user and group
19859 names that are requested and returned from LDAP.
19861 Defaults to @samp{disabled}.
19865 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
19866 This specifies whether or not to perform searches using case-insensitive
19867 matching. Enabling this could open up the system to authorization
19868 bypass vulnerabilities and introduce nscd cache poisoning
19869 vulnerabilities which allow denial of service.
19871 Defaults to @samp{disabled}.
19875 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
19876 This option specifies whether password policy controls are requested and
19877 handled from the LDAP server when performing user authentication.
19879 Defaults to @samp{disabled}.
19883 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
19884 By default nslcd performs an LDAP search with the user's credentials
19885 after BIND (authentication) to ensure that the BIND operation was
19886 successful. The default search is a simple check to see if the user's
19887 DN exists. A search filter can be specified that will be used instead.
19888 It should return at least one entry.
19890 Defaults to @samp{disabled}.
19894 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
19895 This option allows flexible fine tuning of the authorisation check that
19896 should be performed. The search filter specified is executed and if any
19897 entries match, access is granted, otherwise access is denied.
19899 Defaults to @samp{disabled}.
19903 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
19904 If this option is set password modification using pam_ldap will be
19905 denied and the specified message will be presented to the user instead.
19906 The message can be used to direct the user to an alternative means of
19907 changing their password.
19909 Defaults to @samp{disabled}.
19913 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
19914 List of pam service names for which LDAP authentication should suffice.
19916 Defaults to @samp{()}.
19920 @c %end of generated documentation for nslcd-configuration
19924 @subsection Web Services
19929 The @code{(gnu services web)} module provides the Apache HTTP Server,
19930 the nginx web server, and also a fastcgi wrapper daemon.
19932 @subsubheading Apache HTTP Server
19934 @deffn {Scheme Variable} httpd-service-type
19935 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
19936 (@dfn{httpd}). The value for this service type is a
19937 @code{httpd-configuration} record.
19939 A simple example configuration is given below.
19942 (service httpd-service-type
19943 (httpd-configuration
19946 (server-name "www.example.com")
19947 (document-root "/srv/http/www.example.com")))))
19950 Other services can also extend the @code{httpd-service-type} to add to
19954 (simple-service 'www.example.com-server httpd-service-type
19958 (list (string-join '("ServerName www.example.com"
19959 "DocumentRoot /srv/http/www.example.com")
19964 The details for the @code{httpd-configuration}, @code{httpd-module},
19965 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
19968 @deffn {Data Type} httpd-configuration
19969 This data type represents the configuration for the httpd service.
19972 @item @code{package} (default: @code{httpd})
19973 The httpd package to use.
19975 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19976 The pid file used by the shepherd-service.
19978 @item @code{config} (default: @code{(httpd-config-file)})
19979 The configuration file to use with the httpd service. The default value
19980 is a @code{httpd-config-file} record, but this can also be a different
19981 G-expression that generates a file, for example a @code{plain-file}. A
19982 file outside of the store can also be specified through a string.
19987 @deffn {Data Type} httpd-module
19988 This data type represents a module for the httpd service.
19992 The name of the module.
19995 The file for the module. This can be relative to the httpd package being
19996 used, the absolute location of a file, or a G-expression for a file
19997 within the store, for example @code{(file-append mod-wsgi
19998 "/modules/mod_wsgi.so")}.
20003 @defvr {Scheme Variable} %default-httpd-modules
20004 A default list of @code{httpd-module} objects.
20007 @deffn {Data Type} httpd-config-file
20008 This data type represents a configuration file for the httpd service.
20011 @item @code{modules} (default: @code{%default-httpd-modules})
20012 The modules to load. Additional modules can be added here, or loaded by
20013 additional configuration.
20015 For example, in order to handle requests for PHP files, you can use Apache’s
20016 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
20019 (service httpd-service-type
20020 (httpd-configuration
20025 (name "proxy_module")
20026 (file "modules/mod_proxy.so"))
20028 (name "proxy_fcgi_module")
20029 (file "modules/mod_proxy_fcgi.so"))
20030 %default-httpd-modules))
20031 (extra-config (list "\
20032 <FilesMatch \\.php$>
20033 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
20034 </FilesMatch>"))))))
20035 (service php-fpm-service-type
20036 (php-fpm-configuration
20037 (socket "/var/run/php-fpm.sock")
20038 (socket-group "httpd")))
20041 @item @code{server-root} (default: @code{httpd})
20042 The @code{ServerRoot} in the configuration file, defaults to the httpd
20043 package. Directives including @code{Include} and @code{LoadModule} are
20044 taken as relative to the server root.
20046 @item @code{server-name} (default: @code{#f})
20047 The @code{ServerName} in the configuration file, used to specify the
20048 request scheme, hostname and port that the server uses to identify
20051 This doesn't need to be set in the server config, and can be specifyed
20052 in virtual hosts. The default is @code{#f} to not specify a
20055 @item @code{document-root} (default: @code{"/srv/http"})
20056 The @code{DocumentRoot} from which files will be served.
20058 @item @code{listen} (default: @code{'("80")})
20059 The list of values for the @code{Listen} directives in the config
20060 file. The value should be a list of strings, when each string can
20061 specify the port number to listen on, and optionally the IP address and
20064 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20065 The @code{PidFile} to use. This should match the @code{pid-file} set in
20066 the @code{httpd-configuration} so that the Shepherd service is
20067 configured correctly.
20069 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
20070 The @code{ErrorLog} to which the server will log errors.
20072 @item @code{user} (default: @code{"httpd"})
20073 The @code{User} which the server will answer requests as.
20075 @item @code{group} (default: @code{"httpd"})
20076 The @code{Group} which the server will answer requests as.
20078 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
20079 A flat list of strings and G-expressions which will be added to the end
20080 of the configuration file.
20082 Any values which the service is extended with will be appended to this
20088 @deffn {Data Type} httpd-virtualhost
20089 This data type represents a virtualhost configuration block for the httpd service.
20091 These should be added to the extra-config for the httpd-service.
20094 (simple-service 'www.example.com-server httpd-service-type
20098 (list (string-join '("ServerName www.example.com"
20099 "DocumentRoot /srv/http/www.example.com")
20104 @item @code{addresses-and-ports}
20105 The addresses and ports for the @code{VirtualHost} directive.
20107 @item @code{contents}
20108 The contents of the @code{VirtualHost} directive, this should be a list
20109 of strings and G-expressions.
20114 @subsubheading NGINX
20116 @deffn {Scheme Variable} nginx-service-type
20117 Service type for the @uref{https://nginx.org/,NGinx} web server. The
20118 value for this service type is a @code{<nginx-configuration>} record.
20120 A simple example configuration is given below.
20123 (service nginx-service-type
20124 (nginx-configuration
20126 (list (nginx-server-configuration
20127 (server-name '("www.example.com"))
20128 (root "/srv/http/www.example.com"))))))
20131 In addition to adding server blocks to the service configuration
20132 directly, this service can be extended by other services to add server
20133 blocks, as in this example:
20136 (simple-service 'my-extra-server nginx-service-type
20137 (list (nginx-server-configuration
20138 (root "/srv/http/extra-website")
20139 (try-files (list "$uri" "$uri/index.html")))))
20143 At startup, @command{nginx} has not yet read its configuration file, so
20144 it uses a default file to log error messages. If it fails to load its
20145 configuration file, that is where error messages are logged. After the
20146 configuration file is loaded, the default error log file changes as per
20147 configuration. In our case, startup error messages can be found in
20148 @file{/var/run/nginx/logs/error.log}, and after configuration in
20149 @file{/var/log/nginx/error.log}. The second location can be changed
20150 with the @var{log-directory} configuration option.
20152 @deffn {Data Type} nginx-configuration
20153 This data type represents the configuration for NGinx. Some
20154 configuration can be done through this and the other provided record
20155 types, or alternatively, a config file can be provided.
20158 @item @code{nginx} (default: @code{nginx})
20159 The nginx package to use.
20161 @item @code{log-directory} (default: @code{"/var/log/nginx"})
20162 The directory to which NGinx will write log files.
20164 @item @code{run-directory} (default: @code{"/var/run/nginx"})
20165 The directory in which NGinx will create a pid file, and write temporary
20168 @item @code{server-blocks} (default: @code{'()})
20169 A list of @dfn{server blocks} to create in the generated configuration
20170 file, the elements should be of type
20171 @code{<nginx-server-configuration>}.
20173 The following example would setup NGinx to serve @code{www.example.com}
20174 from the @code{/srv/http/www.example.com} directory, without using
20177 (service nginx-service-type
20178 (nginx-configuration
20180 (list (nginx-server-configuration
20181 (server-name '("www.example.com"))
20182 (root "/srv/http/www.example.com"))))))
20185 @item @code{upstream-blocks} (default: @code{'()})
20186 A list of @dfn{upstream blocks} to create in the generated configuration
20187 file, the elements should be of type
20188 @code{<nginx-upstream-configuration>}.
20190 Configuring upstreams through the @code{upstream-blocks} can be useful
20191 when combined with @code{locations} in the
20192 @code{<nginx-server-configuration>} records. The following example
20193 creates a server configuration with one location configuration, that
20194 will proxy requests to a upstream configuration, which will handle
20195 requests with two servers.
20200 (nginx-configuration
20202 (list (nginx-server-configuration
20203 (server-name '("www.example.com"))
20204 (root "/srv/http/www.example.com")
20207 (nginx-location-configuration
20209 (body '("proxy_pass http://server-proxy;"))))))))
20211 (list (nginx-upstream-configuration
20212 (name "server-proxy")
20213 (servers (list "server1.example.com"
20214 "server2.example.com")))))))
20217 @item @code{file} (default: @code{#f})
20218 If a configuration @var{file} is provided, this will be used, rather than
20219 generating a configuration file from the provided @code{log-directory},
20220 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
20221 proper operation, these arguments should match what is in @var{file} to ensure
20222 that the directories are created when the service is activated.
20224 This can be useful if you have an existing configuration file, or it's
20225 not possible to do what is required through the other parts of the
20226 nginx-configuration record.
20228 @item @code{server-names-hash-bucket-size} (default: @code{#f})
20229 Bucket size for the server names hash tables, defaults to @code{#f} to
20230 use the size of the processors cache line.
20232 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
20233 Maximum bucket size for the server names hash tables.
20235 @item @code{modules} (default: @code{'()})
20236 List of nginx dynamic modules to load. This should be a list of file
20237 names of loadable modules, as in this example:
20242 (file-append nginx-accept-language-module "\
20243 /etc/nginx/modules/ngx_http_accept_language_module.so")))
20246 @item @code{extra-content} (default: @code{""})
20247 Extra content for the @code{http} block. Should be string or a string
20248 valued G-expression.
20253 @deftp {Data Type} nginx-server-configuration
20254 Data type representing the configuration of an nginx server block.
20255 This type has the following parameters:
20258 @item @code{listen} (default: @code{'("80" "443 ssl")})
20259 Each @code{listen} directive sets the address and port for IP, or the
20260 path for a UNIX-domain socket on which the server will accept requests.
20261 Both address and port, or only address or only port can be specified.
20262 An address may also be a hostname, for example:
20265 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
20268 @item @code{server-name} (default: @code{(list 'default)})
20269 A list of server names this server represents. @code{'default} represents the
20270 default server for connections matching no other server.
20272 @item @code{root} (default: @code{"/srv/http"})
20273 Root of the website nginx will serve.
20275 @item @code{locations} (default: @code{'()})
20276 A list of @dfn{nginx-location-configuration} or
20277 @dfn{nginx-named-location-configuration} records to use within this
20280 @item @code{index} (default: @code{(list "index.html")})
20281 Index files to look for when clients ask for a directory. If it cannot be found,
20282 Nginx will send the list of files in the directory.
20284 @item @code{try-files} (default: @code{'()})
20285 A list of files whose existence is checked in the specified order.
20286 @code{nginx} will use the first file it finds to process the request.
20288 @item @code{ssl-certificate} (default: @code{#f})
20289 Where to find the certificate for secure connections. Set it to @code{#f} if
20290 you don't have a certificate or you don't want to use HTTPS.
20292 @item @code{ssl-certificate-key} (default: @code{#f})
20293 Where to find the private key for secure connections. Set it to @code{#f} if
20294 you don't have a key or you don't want to use HTTPS.
20296 @item @code{server-tokens?} (default: @code{#f})
20297 Whether the server should add its configuration to response.
20299 @item @code{raw-content} (default: @code{'()})
20300 A list of raw lines added to the server block.
20305 @deftp {Data Type} nginx-upstream-configuration
20306 Data type representing the configuration of an nginx @code{upstream}
20307 block. This type has the following parameters:
20311 Name for this group of servers.
20313 @item @code{servers}
20314 Specify the addresses of the servers in the group. The address can be
20315 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
20316 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
20317 prefix @samp{unix:}. For addresses using an IP address or domain name,
20318 the default port is 80, and a different port can be specified
20324 @deftp {Data Type} nginx-location-configuration
20325 Data type representing the configuration of an nginx @code{location}
20326 block. This type has the following parameters:
20330 URI which this location block matches.
20332 @anchor{nginx-location-configuration body}
20334 Body of the location block, specified as a list of strings. This can contain
20336 configuration directives. For example, to pass requests to a upstream
20337 server group defined using an @code{nginx-upstream-configuration} block,
20338 the following directive would be specified in the body @samp{(list "proxy_pass
20339 http://upstream-name;")}.
20344 @deftp {Data Type} nginx-named-location-configuration
20345 Data type representing the configuration of an nginx named location
20346 block. Named location blocks are used for request redirection, and not
20347 used for regular request processing. This type has the following
20352 Name to identify this location block.
20355 @xref{nginx-location-configuration body}, as the body for named location
20356 blocks can be used in a similar way to the
20357 @code{nginx-location-configuration body}. One restriction is that the
20358 body of a named location block cannot contain location blocks.
20363 @subsubheading Varnish Cache
20365 Varnish is a fast cache server that sits in between web applications
20366 and end users. It proxies requests from clients and caches the
20367 accessed URLs such that multiple requests for the same resource only
20368 creates one request to the back-end.
20370 @defvr {Scheme Variable} varnish-service-type
20371 Service type for the Varnish daemon.
20374 @deftp {Data Type} varnish-configuration
20375 Data type representing the @code{varnish} service configuration.
20376 This type has the following parameters:
20379 @item @code{package} (default: @code{varnish})
20380 The Varnish package to use.
20382 @item @code{name} (default: @code{"default"})
20383 A name for this Varnish instance. Varnish will create a directory in
20384 @file{/var/varnish/} with this name and keep temporary files there. If
20385 the name starts with a forward slash, it is interpreted as an absolute
20388 Pass the @code{-n} argument to other Varnish programs to connect to the
20389 named instance, e.g.@: @command{varnishncsa -n default}.
20391 @item @code{backend} (default: @code{"localhost:8080"})
20392 The backend to use. This option has no effect if @code{vcl} is set.
20394 @item @code{vcl} (default: #f)
20395 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
20396 is @code{#f}, Varnish will proxy @code{backend} using the default
20397 configuration. Otherwise this must be a file-like object with valid
20400 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
20401 For example, to mirror @url{http://www.gnu.org,www.gnu.org} with VCL you
20402 can do something along these lines:
20405 (define %gnu-mirror
20406 (plain-file "gnu.vcl"
20408 backend gnu @{ .host = \"www.gnu.org\"; @}"))
20412 (services (cons (service varnish-service-type
20413 (varnish-configuration
20415 (vcl %gnu-mirror)))
20419 The configuration of an already running Varnish instance can be inspected
20420 and changed using the @command{varnishadm} program.
20422 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
20423 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
20424 comprehensive documentation on Varnish and its configuration language.
20426 @item @code{listen} (default: @code{'("localhost:80")})
20427 List of addresses Varnish will listen on.
20429 @item @code{storage} (default: @code{'("malloc,128m")})
20430 List of storage backends that will be available in VCL.
20432 @item @code{parameters} (default: @code{'()})
20433 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
20435 @item @code{extra-options} (default: @code{'()})
20436 Additional arguments to pass to the @command{varnishd} process.
20441 @subsubheading Patchwork
20443 Patchwork is a patch tracking system. It can collect patches sent to a
20444 mailing list, and display them in a web interface.
20446 @defvr {Scheme Variable} patchwork-service-type
20447 Service type for Patchwork.
20450 The following example is an example of a minimal service for Patchwork, for
20451 the @code{patchwork.example.com} domain.
20454 (service patchwork-service-type
20455 (patchwork-configuration
20456 (domain "patchwork.example.com")
20458 (patchwork-settings-module
20459 (allowed-hosts (list domain))
20460 (default-from-email "patchwork@@patchwork.example.com")))
20461 (getmail-retriever-config
20462 (getmail-retriever-configuration
20463 (type "SimpleIMAPSSLRetriever")
20464 (server "imap.example.com")
20466 (username "patchwork")
20468 (list (file-append coreutils "/bin/cat")
20469 "/etc/getmail-patchwork-imap-password"))
20471 '((mailboxes . ("Patches"))))))))
20475 There are three records for configuring the Patchwork service. The
20476 @code{<patchwork-configuration>} relates to the configuration for Patchwork
20477 within the HTTPD service.
20479 The @code{settings-module} field within the @code{<patchwork-configuration>}
20480 record can be populated with the @code{<patchwork-settings-module>} record,
20481 which describes a settings module that is generated within the Guix store.
20483 For the @code{database-configuration} field within the
20484 @code{<patchwork-settings-module>}, the
20485 @code{<patchwork-database-configuration>} must be used.
20487 @deftp {Data Type} patchwork-configuration
20488 Data type representing the Patchwork service configuration. This type has the
20489 following parameters:
20492 @item @code{patchwork} (default: @code{patchwork})
20493 The Patchwork package to use.
20495 @item @code{domain}
20496 The domain to use for Patchwork, this is used in the HTTPD service virtual
20499 @item @code{settings-module}
20500 The settings module to use for Patchwork. As a Django application, Patchwork
20501 is configured with a Python module containing the settings. This can either be
20502 an instance of the @code{<patchwork-settings-module>} record, any other record
20503 that represents the settings in the store, or a directory outside of the
20506 @item @code{static-path} (default: @code{"/static/"})
20507 The path under which the HTTPD service should serve the static files.
20509 @item @code{getmail-retriever-config}
20510 The getmail-retriever-configuration record value to use with
20511 Patchwork. Getmail will be configured with this value, the messages will be
20512 delivered to Patchwork.
20517 @deftp {Data Type} patchwork-settings-module
20518 Data type representing a settings module for Patchwork. Some of these
20519 settings relate directly to Patchwork, but others relate to Django, the web
20520 framework used by Patchwork, or the Django Rest Framework library. This type
20521 has the following parameters:
20524 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
20525 The database connection settings used for Patchwork. See the
20526 @code{<patchwork-database-configuration>} record type for more information.
20528 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
20529 Patchwork, as a Django web application uses a secret key for cryptographically
20530 signing values. This file should contain a unique unpredictable value.
20532 If this file does not exist, it will be created and populated with a random
20533 value by the patchwork-setup shepherd service.
20535 This setting relates to Django.
20537 @item @code{allowed-hosts}
20538 A list of valid hosts for this Patchwork service. This should at least include
20539 the domain specified in the @code{<patchwork-configuration>} record.
20541 This is a Django setting.
20543 @item @code{default-from-email}
20544 The email address from which Patchwork should send email by default.
20546 This is a Patchwork setting.
20548 @item @code{static-url} (default: @code{#f})
20549 The URL to use when serving static assets. It can be part of a URL, or a full
20550 URL, but must end in a @code{/}.
20552 If the default value is used, the @code{static-path} value from the
20553 @code{<patchwork-configuration>} record will be used.
20555 This is a Django setting.
20557 @item @code{admins} (default: @code{'()})
20558 Email addresses to send the details of errors that occur. Each value should
20559 be a list containing two elements, the name and then the email address.
20561 This is a Django setting.
20563 @item @code{debug?} (default: @code{#f})
20564 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
20565 messages will be shown.
20567 This is a Django setting.
20569 @item @code{enable-rest-api?} (default: @code{#t})
20570 Whether to enable the Patchwork REST API.
20572 This is a Patchwork setting.
20574 @item @code{enable-xmlrpc?} (default: @code{#t})
20575 Whether to enable the XML RPC API.
20577 This is a Patchwork setting.
20579 @item @code{force-https-links?} (default: @code{#t})
20580 Whether to use HTTPS links on Patchwork pages.
20582 This is a Patchwork setting.
20584 @item @code{extra-settings} (default: @code{""})
20585 Extra code to place at the end of the Patchwork settings module.
20590 @deftp {Data Type} patchwork-database-configuration
20591 Data type representing the database configuration for Patchwork.
20594 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
20595 The database engine to use.
20597 @item @code{name} (default: @code{"patchwork"})
20598 The name of the database to use.
20600 @item @code{user} (default: @code{"httpd"})
20601 The user to connect to the database as.
20603 @item @code{password} (default: @code{""})
20604 The password to use when connecting to the database.
20606 @item @code{host} (default: @code{""})
20607 The host to make the database connection to.
20609 @item @code{port} (default: @code{""})
20610 The port on which to connect to the database.
20615 @subsubheading Mumi
20617 @cindex Mumi, Debbugs Web interface
20618 @cindex Debbugs, Mumi Web interface
20619 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
20620 Web interface to the Debbugs bug tracker, by default for
20621 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
20622 but it also fetches and indexes mail retrieved from Debbugs.
20624 @defvr {Scheme Variable} mumi-service-type
20625 This is the service type for Mumi.
20628 @subsubheading FastCGI
20631 FastCGI is an interface between the front-end and the back-end of a web
20632 service. It is a somewhat legacy facility; new web services should
20633 generally just talk HTTP between the front-end and the back-end.
20634 However there are a number of back-end services such as PHP or the
20635 optimized HTTP Git repository access that use FastCGI, so we have
20636 support for it in Guix.
20638 To use FastCGI, you configure the front-end web server (e.g., nginx) to
20639 dispatch some subset of its requests to the fastcgi backend, which
20640 listens on a local TCP or UNIX socket. There is an intermediary
20641 @code{fcgiwrap} program that sits between the actual backend process and
20642 the web server. The front-end indicates which backend program to run,
20643 passing that information to the @code{fcgiwrap} process.
20645 @defvr {Scheme Variable} fcgiwrap-service-type
20646 A service type for the @code{fcgiwrap} FastCGI proxy.
20649 @deftp {Data Type} fcgiwrap-configuration
20650 Data type representing the configuration of the @code{fcgiwrap} service.
20651 This type has the following parameters:
20653 @item @code{package} (default: @code{fcgiwrap})
20654 The fcgiwrap package to use.
20656 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
20657 The socket on which the @code{fcgiwrap} process should listen, as a
20658 string. Valid @var{socket} values include
20659 @code{unix:@var{/path/to/unix/socket}},
20660 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
20661 @code{tcp6:[@var{ipv6_addr}]:port}.
20663 @item @code{user} (default: @code{fcgiwrap})
20664 @itemx @code{group} (default: @code{fcgiwrap})
20665 The user and group names, as strings, under which to run the
20666 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
20667 the user asks for the specific user or group names @code{fcgiwrap} that
20668 the corresponding user and/or group is present on the system.
20670 It is possible to configure a FastCGI-backed web service to pass HTTP
20671 authentication information from the front-end to the back-end, and to
20672 allow @code{fcgiwrap} to run the back-end process as a corresponding
20673 local user. To enable this capability on the back-end, run
20674 @code{fcgiwrap} as the @code{root} user and group. Note that this
20675 capability also has to be configured on the front-end as well.
20680 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
20681 with some additional features useful for sites of any size.
20683 These features include:
20685 @item Adaptive process spawning
20686 @item Basic statistics (similar to Apache's mod_status)
20687 @item Advanced process management with graceful stop/start
20688 @item Ability to start workers with different uid/gid/chroot/environment
20689 and different php.ini (replaces safe_mode)
20690 @item Stdout & stderr logging
20691 @item Emergency restart in case of accidental opcode cache destruction
20692 @item Accelerated upload support
20693 @item Support for a "slowlog"
20694 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
20695 a special function to finish request & flush all data while continuing to do
20696 something time-consuming (video converting, stats processing, etc.)
20698 ...@: and much more.
20700 @defvr {Scheme Variable} php-fpm-service-type
20701 A Service type for @code{php-fpm}.
20704 @deftp {Data Type} php-fpm-configuration
20705 Data Type for php-fpm service configuration.
20707 @item @code{php} (default: @code{php})
20708 The php package to use.
20709 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
20710 The address on which to accept FastCGI requests. Valid syntaxes are:
20712 @item @code{"ip.add.re.ss:port"}
20713 Listen on a TCP socket to a specific address on a specific port.
20714 @item @code{"port"}
20715 Listen on a TCP socket to all addresses on a specific port.
20716 @item @code{"/path/to/unix/socket"}
20717 Listen on a unix socket.
20720 @item @code{user} (default: @code{php-fpm})
20721 User who will own the php worker processes.
20722 @item @code{group} (default: @code{php-fpm})
20723 Group of the worker processes.
20724 @item @code{socket-user} (default: @code{php-fpm})
20725 User who can speak to the php-fpm socket.
20726 @item @code{socket-group} (default: @code{nginx})
20727 Group that can speak to the php-fpm socket.
20728 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
20729 The process id of the php-fpm process is written to this file
20730 once the service has started.
20731 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
20732 Log for the php-fpm master process.
20733 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
20734 Detailed settings for the php-fpm process manager.
20737 @item @code{<php-fpm-dynamic-process-manager-configuration>}
20738 @item @code{<php-fpm-static-process-manager-configuration>}
20739 @item @code{<php-fpm-on-demand-process-manager-configuration>}
20741 @item @code{display-errors} (default @code{#f})
20742 Determines whether php errors and warning should be sent to clients
20743 and displayed in their browsers.
20744 This is useful for local php development, but a security risk for public sites,
20745 as error messages can reveal passwords and personal data.
20746 @item @code{timezone} (default @code{#f})
20747 Specifies @code{php_admin_value[date.timezone]} parameter.
20748 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
20749 This file will log the @code{stderr} outputs of php worker processes.
20750 Can be set to @code{#f} to disable logging.
20751 @item @code{file} (default @code{#f})
20752 An optional override of the whole configuration.
20753 You can use the @code{mixed-text-file} function or an absolute filepath for it.
20757 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
20758 Data Type for the @code{dynamic} php-fpm process manager. With the
20759 @code{dynamic} process manager, spare worker processes are kept around
20760 based on it's configured limits.
20762 @item @code{max-children} (default: @code{5})
20763 Maximum of worker processes.
20764 @item @code{start-servers} (default: @code{2})
20765 How many worker processes should be started on start-up.
20766 @item @code{min-spare-servers} (default: @code{1})
20767 How many spare worker processes should be kept around at minimum.
20768 @item @code{max-spare-servers} (default: @code{3})
20769 How many spare worker processes should be kept around at maximum.
20773 @deftp {Data type} php-fpm-static-process-manager-configuration
20774 Data Type for the @code{static} php-fpm process manager. With the
20775 @code{static} process manager, an unchanging number of worker processes
20778 @item @code{max-children} (default: @code{5})
20779 Maximum of worker processes.
20783 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
20784 Data Type for the @code{on-demand} php-fpm process manager. With the
20785 @code{on-demand} process manager, worker processes are only created as
20788 @item @code{max-children} (default: @code{5})
20789 Maximum of worker processes.
20790 @item @code{process-idle-timeout} (default: @code{10})
20791 The time in seconds after which a process with no requests is killed.
20796 @deffn {Scheme Procedure} nginx-php-fpm-location @
20797 [#:nginx-package nginx] @
20798 [socket (string-append "/var/run/php" @
20799 (version-major (package-version php)) @
20801 A helper function to quickly add php to an @code{nginx-server-configuration}.
20804 A simple services setup for nginx with php can look like this:
20806 (services (cons* (service dhcp-client-service-type)
20807 (service php-fpm-service-type)
20808 (service nginx-service-type
20809 (nginx-server-configuration
20810 (server-name '("example.com"))
20811 (root "/srv/http/")
20813 (list (nginx-php-location)))
20815 (ssl-certificate #f)
20816 (ssl-certificate-key #f)))
20820 @cindex cat-avatar-generator
20821 The cat avatar generator is a simple service to demonstrate the use of php-fpm
20822 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
20823 the hash of a user's email address.
20825 @deffn {Scheme Procedure} cat-avatar-generator-service @
20826 [#:cache-dir "/var/cache/cat-avatar-generator"] @
20827 [#:package cat-avatar-generator] @
20828 [#:configuration (nginx-server-configuration)]
20829 Returns an nginx-server-configuration that inherits @code{configuration}. It
20830 extends the nginx configuration to add a server block that serves @code{package},
20831 a version of cat-avatar-generator. During execution, cat-avatar-generator will
20832 be able to use @code{cache-dir} as its cache directory.
20835 A simple setup for cat-avatar-generator can look like this:
20837 (services (cons* (cat-avatar-generator-service
20839 (nginx-server-configuration
20840 (server-name '("example.com"))))
20845 @subsubheading Hpcguix-web
20847 @cindex hpcguix-web
20848 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
20849 program is a customizable web interface to browse Guix packages,
20850 initially designed for users of high-performance computing (HPC)
20853 @defvr {Scheme Variable} hpcguix-web-service-type
20854 The service type for @code{hpcguix-web}.
20857 @deftp {Data Type} hpcguix-web-configuration
20858 Data type for the hpcguix-web service configuration.
20862 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
20863 configuration. The main items available in this spec are:
20866 @item @code{title-prefix} (default: @code{"hpcguix | "})
20867 The page title prefix.
20869 @item @code{guix-command} (default: @code{"guix"})
20870 The @command{guix} command.
20872 @item @code{package-filter-proc} (default: @code{(const #t)})
20873 A procedure specifying how to filter packages that are displayed.
20875 @item @code{package-page-extension-proc} (default: @code{(const '())})
20876 Extension package for @code{hpcguix-web}.
20878 @item @code{menu} (default: @code{'()})
20879 Additional entry in page @code{menu}.
20881 @item @code{channels} (default: @code{%default-channels})
20882 List of channels from which the package list is built (@pxref{Channels}).
20884 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
20885 The expiration time, in seconds, after which the package list is rebuilt from
20886 the latest instances of the given channels.
20889 See the hpcguix-web repository for a
20890 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
20893 @item @code{package} (default: @code{hpcguix-web})
20894 The hpcguix-web package to use.
20898 A typical hpcguix-web service declaration looks like this:
20901 (service hpcguix-web-service-type
20902 (hpcguix-web-configuration
20904 #~(define site-config
20905 (hpcweb-configuration
20906 (title-prefix "Guix-HPC - ")
20907 (menu '(("/about" "ABOUT"))))))))
20911 The hpcguix-web service periodically updates the package list it publishes by
20912 pulling channels from Git. To that end, it needs to access X.509 certificates
20913 so that it can authenticate Git servers when communicating over HTTPS, and it
20914 assumes that @file{/etc/ssl/certs} contains those certificates.
20916 Thus, make sure to add @code{nss-certs} or another certificate package to the
20917 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
20918 more information on X.509 certificates.
20921 @node Certificate Services
20922 @subsection Certificate Services
20925 @cindex HTTP, HTTPS
20926 @cindex Let's Encrypt
20927 @cindex TLS certificates
20928 The @code{(gnu services certbot)} module provides a service to
20929 automatically obtain a valid TLS certificate from the Let's Encrypt
20930 certificate authority. These certificates can then be used to serve
20931 content securely over HTTPS or other TLS-based protocols, with the
20932 knowledge that the client will be able to verify the server's
20935 @url{https://letsencrypt.org/, Let's Encrypt} provides the
20936 @code{certbot} tool to automate the certification process. This tool
20937 first securely generates a key on the server. It then makes a request
20938 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
20939 checks that the request originates from the host in question by using a
20940 challenge-response protocol, requiring the server to provide its
20941 response over HTTP. If that protocol completes successfully, the CA
20942 signs the key, resulting in a certificate. That certificate is valid
20943 for a limited period of time, and therefore to continue to provide TLS
20944 services, the server needs to periodically ask the CA to renew its
20947 The certbot service automates this process: the initial key
20948 generation, the initial certification request to the Let's Encrypt
20949 service, the web server challenge/response integration, writing the
20950 certificate to disk, the automated periodic renewals, and the deployment
20951 tasks associated with the renewal (e.g.@: reloading services, copying keys
20952 with different permissions).
20954 Certbot is run twice a day, at a random minute within the hour. It
20955 won't do anything until your certificates are due for renewal or
20956 revoked, but running it regularly would give your service a chance of
20957 staying online in case a Let's Encrypt-initiated revocation happened for
20960 By using this service, you agree to the ACME Subscriber Agreement, which
20961 can be found there:
20962 @url{https://acme-v01.api.letsencrypt.org/directory}.
20964 @defvr {Scheme Variable} certbot-service-type
20965 A service type for the @code{certbot} Let's Encrypt client. Its value
20966 must be a @code{certbot-configuration} record as in this example:
20969 (define %nginx-deploy-hook
20971 "nginx-deploy-hook"
20972 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
20973 (kill pid SIGHUP))))
20975 (service certbot-service-type
20976 (certbot-configuration
20977 (email "foo@@example.net")
20980 (certificate-configuration
20981 (domains '("example.net" "www.example.net"))
20982 (deploy-hook %nginx-deploy-hook))
20983 (certificate-configuration
20984 (domains '("bar.example.net")))))))
20987 See below for details about @code{certbot-configuration}.
20990 @deftp {Data Type} certbot-configuration
20991 Data type representing the configuration of the @code{certbot} service.
20992 This type has the following parameters:
20995 @item @code{package} (default: @code{certbot})
20996 The certbot package to use.
20998 @item @code{webroot} (default: @code{/var/www})
20999 The directory from which to serve the Let's Encrypt challenge/response
21002 @item @code{certificates} (default: @code{()})
21003 A list of @code{certificates-configuration}s for which to generate
21004 certificates and request signatures. Each certificate has a @code{name}
21005 and several @code{domains}.
21008 Mandatory email used for registration, recovery contact, and important
21009 account notifications.
21011 @item @code{rsa-key-size} (default: @code{2048})
21012 Size of the RSA key.
21014 @item @code{default-location} (default: @i{see below})
21015 The default @code{nginx-location-configuration}. Because @code{certbot}
21016 needs to be able to serve challenges and responses, it needs to be able
21017 to run a web server. It does so by extending the @code{nginx} web
21018 service with an @code{nginx-server-configuration} listening on the
21019 @var{domains} on port 80, and which has a
21020 @code{nginx-location-configuration} for the @code{/.well-known/} URI
21021 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
21022 these nginx configuration data types.
21024 Requests to other URL paths will be matched by the
21025 @code{default-location}, which if present is added to all
21026 @code{nginx-server-configuration}s.
21028 By default, the @code{default-location} will issue a redirect from
21029 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
21030 you to define what to serve on your site via @code{https}.
21032 Pass @code{#f} to not issue a default location.
21036 @deftp {Data Type} certificate-configuration
21037 Data type representing the configuration of a certificate.
21038 This type has the following parameters:
21041 @item @code{name} (default: @i{see below})
21042 This name is used by Certbot for housekeeping and in file paths; it
21043 doesn't affect the content of the certificate itself. To see
21044 certificate names, run @code{certbot certificates}.
21046 Its default is the first provided domain.
21048 @item @code{domains} (default: @code{()})
21049 The first domain provided will be the subject CN of the certificate, and
21050 all domains will be Subject Alternative Names on the certificate.
21052 @item @code{challenge} (default: @code{#f})
21053 The challenge type that has to be run by certbot. If @code{#f} is specified,
21054 default to the HTTP challenge. If a value is specified, defaults to the
21055 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
21056 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
21057 and gives Let's Encrypt permission to log the public IP address of the
21058 requesting machine.
21060 @item @code{authentication-hook} (default: @code{#f})
21061 Command to be run in a shell once for each certificate challenge to be
21062 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
21063 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
21064 contains the validation string and @code{$CERTBOT_TOKEN} contains the
21065 file name of the resource requested when performing an HTTP-01 challenge.
21067 @item @code{cleanup-hook} (default: @code{#f})
21068 Command to be run in a shell once for each certificate challenge that
21069 have been answered by the @code{auth-hook}. For this command, the shell
21070 variables available in the @code{auth-hook} script are still available, and
21071 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
21072 of the @code{auth-hook} script.
21074 @item @code{deploy-hook} (default: @code{#f})
21075 Command to be run in a shell once for each successfully issued
21076 certificate. For this command, the shell variable
21077 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
21078 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
21079 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
21080 contain a space-delimited list of renewed certificate domains (for
21081 example, @samp{"example.com www.example.com"}.
21086 For each @code{certificate-configuration}, the certificate is saved to
21087 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
21088 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
21090 @subsection DNS Services
21091 @cindex DNS (domain name system)
21092 @cindex domain name system (DNS)
21094 The @code{(gnu services dns)} module provides services related to the
21095 @dfn{domain name system} (DNS). It provides a server service for hosting
21096 an @emph{authoritative} DNS server for multiple zones, slave or master.
21097 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
21098 caching and forwarding DNS server for the LAN, which uses
21099 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
21101 @subsubheading Knot Service
21103 An example configuration of an authoritative server for two zones, one master
21107 (define-zone-entries example.org.zone
21108 ;; Name TTL Class Type Data
21109 ("@@" "" "IN" "A" "127.0.0.1")
21110 ("@@" "" "IN" "NS" "ns")
21111 ("ns" "" "IN" "A" "127.0.0.1"))
21113 (define master-zone
21114 (knot-zone-configuration
21115 (domain "example.org")
21117 (origin "example.org")
21118 (entries example.org.zone)))))
21121 (knot-zone-configuration
21122 (domain "plop.org")
21123 (dnssec-policy "default")
21124 (master (list "plop-master"))))
21126 (define plop-master
21127 (knot-remote-configuration
21129 (address (list "208.76.58.171"))))
21133 (services (cons* (service knot-service-type
21134 (knot-configuration
21135 (remotes (list plop-master))
21136 (zones (list master-zone slave-zone))))
21141 @deffn {Scheme Variable} knot-service-type
21142 This is the type for the Knot DNS server.
21144 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
21145 zones, that is to say domain names you would buy from a registrar. This server
21146 is not a resolver, meaning that it can only resolve names for which it is
21147 authoritative. This server can be configured to serve zones as a master server
21148 or a slave server as a per-zone basis. Slave zones will get their data from
21149 masters, and will serve it as an authoritative server. From the point of view
21150 of a resolver, there is no difference between master and slave.
21152 The following data types are used to configure the Knot DNS server:
21155 @deftp {Data Type} knot-key-configuration
21156 Data type representing a key.
21157 This type has the following parameters:
21160 @item @code{id} (default: @code{""})
21161 An identifier for other configuration fields to refer to this key. IDs must
21162 be unique and must not be empty.
21164 @item @code{algorithm} (default: @code{#f})
21165 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
21166 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
21167 and @code{'hmac-sha512}.
21169 @item @code{secret} (default: @code{""})
21170 The secret key itself.
21175 @deftp {Data Type} knot-acl-configuration
21176 Data type representing an Access Control List (ACL) configuration.
21177 This type has the following parameters:
21180 @item @code{id} (default: @code{""})
21181 An identifier for ether configuration fields to refer to this key. IDs must be
21182 unique and must not be empty.
21184 @item @code{address} (default: @code{'()})
21185 An ordered list of IP addresses, network subnets, or network ranges represented
21186 with strings. The query must match one of them. Empty value means that
21187 address match is not required.
21189 @item @code{key} (default: @code{'()})
21190 An ordered list of references to keys represented with strings. The string
21191 must match a key ID defined in a @code{knot-key-configuration}. No key means
21192 that a key is not require to match that ACL.
21194 @item @code{action} (default: @code{'()})
21195 An ordered list of actions that are permitted or forbidden by this ACL. Possible
21196 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
21197 and @code{'update}.
21199 @item @code{deny?} (default: @code{#f})
21200 When true, the ACL defines restrictions. Listed actions are forbidden. When
21201 false, listed actions are allowed.
21206 @deftp {Data Type} zone-entry
21207 Data type represnting a record entry in a zone file.
21208 This type has the following parameters:
21211 @item @code{name} (default: @code{"@@"})
21212 The name of the record. @code{"@@"} refers to the origin of the zone. Names
21213 are relative to the origin of the zone. For example, in the @code{example.org}
21214 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
21215 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
21216 refers to @code{ns.example.org}.
21218 @item @code{ttl} (default: @code{""})
21219 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
21221 @item @code{class} (default: @code{"IN"})
21222 The class of the record. Knot currently supports only @code{"IN"} and
21223 partially @code{"CH"}.
21225 @item @code{type} (default: @code{"A"})
21226 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
21227 address), NS (Name Server) and MX (Mail eXchange). Many other types are
21230 @item @code{data} (default: @code{""})
21231 The data contained in the record. For instance an IP address associated with
21232 an A record, or a domain name associated with an NS record. Remember that
21233 domain names are relative to the origin unless they end with a dot.
21238 @deftp {Data Type} zone-file
21239 Data type representing the content of a zone file.
21240 This type has the following parameters:
21243 @item @code{entries} (default: @code{'()})
21244 The list of entries. The SOA record is taken care of, so you don't need to
21245 put it in the list of entries. This list should probably contain an entry
21246 for your primary authoritative DNS server. Other than using a list of entries
21247 directly, you can use @code{define-zone-entries} to define a object containing
21248 the list of entries more easily, that you can later pass to the @code{entries}
21249 field of the @code{zone-file}.
21251 @item @code{origin} (default: @code{""})
21252 The name of your zone. This parameter cannot be empty.
21254 @item @code{ns} (default: @code{"ns"})
21255 The domain of your primary authoritative DNS server. The name is relative to
21256 the origin, unless it ends with a dot. It is mandatory that this primary
21257 DNS server corresponds to an NS record in the zone and that it is associated
21258 to an IP address in the list of entries.
21260 @item @code{mail} (default: @code{"hostmaster"})
21261 An email address people can contact you at, as the owner of the zone. This
21262 is translated as @code{<mail>@@<origin>}.
21264 @item @code{serial} (default: @code{1})
21265 The serial number of the zone. As this is used to keep track of changes by
21266 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
21267 Always increment it when you make a change in your zone.
21269 @item @code{refresh} (default: @code{(* 2 24 3600)})
21270 The frequency at which slaves will do a zone transfer. This value is a number
21271 of seconds. It can be computed by multiplications or with
21272 @code{(string->duration)}.
21274 @item @code{retry} (default: @code{(* 15 60)})
21275 The period after which a slave will retry to contact its master when it fails
21276 to do so a first time.
21278 @item @code{expiry} (default: @code{(* 14 24 3600)})
21279 Default TTL of records. Existing records are considered correct for at most
21280 this amount of time. After this period, resolvers will invalidate their cache
21281 and check again that it still exists.
21283 @item @code{nx} (default: @code{3600})
21284 Default TTL of inexistant records. This delay is usually short because you want
21285 your new domains to reach everyone quickly.
21290 @deftp {Data Type} knot-remote-configuration
21291 Data type representing a remote configuration.
21292 This type has the following parameters:
21295 @item @code{id} (default: @code{""})
21296 An identifier for other configuration fields to refer to this remote. IDs must
21297 be unique and must not be empty.
21299 @item @code{address} (default: @code{'()})
21300 An ordered list of destination IP addresses. Addresses are tried in sequence.
21301 An optional port can be given with the @@ separator. For instance:
21302 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
21304 @item @code{via} (default: @code{'()})
21305 An ordered list of source IP addresses. An empty list will have Knot choose
21306 an appropriate source IP. An optional port can be given with the @@ separator.
21307 The default is to choose at random.
21309 @item @code{key} (default: @code{#f})
21310 A reference to a key, that is a string containing the identifier of a key
21311 defined in a @code{knot-key-configuration} field.
21316 @deftp {Data Type} knot-keystore-configuration
21317 Data type representing a keystore to hold dnssec keys.
21318 This type has the following parameters:
21321 @item @code{id} (default: @code{""})
21322 The id of the keystore. It must not be empty.
21324 @item @code{backend} (default: @code{'pem})
21325 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
21327 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
21328 The configuration string of the backend. An example for the PKCS#11 is:
21329 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
21330 For the pem backend, the string reprensents a path in the file system.
21335 @deftp {Data Type} knot-policy-configuration
21336 Data type representing a dnssec policy. Knot DNS is able to automatically
21337 sign your zones. It can either generate and manage your keys automatically or
21338 use keys that you generate.
21340 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
21341 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
21342 zone. In order to be trusted, the KSK needs to be present in the parent zone
21343 (usually a top-level domain). If your registrar supports dnssec, you will
21344 have to send them your KSK's hash so they can add a DS record in their zone.
21345 This is not automated and need to be done each time you change your KSK.
21347 The policy also defines the lifetime of keys. Usually, ZSK can be changed
21348 easily and use weaker cryptographic functions (they use lower parameters) in
21349 order to sign records quickly, so they are changed often. The KSK however
21350 requires manual interaction with the registrar, so they are changed less often
21351 and use stronger parameters because they sign only one record.
21353 This type has the following parameters:
21356 @item @code{id} (default: @code{""})
21357 The id of the policy. It must not be empty.
21359 @item @code{keystore} (default: @code{"default"})
21360 A reference to a keystore, that is a string containing the identifier of a
21361 keystore defined in a @code{knot-keystore-configuration} field. The
21362 @code{"default"} identifier means the default keystore (a kasp database that
21363 was setup by this service).
21365 @item @code{manual?} (default: @code{#f})
21366 Whether the key management is manual or automatic.
21368 @item @code{single-type-signing?} (default: @code{#f})
21369 When @code{#t}, use the Single-Type Signing Scheme.
21371 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
21372 An algorithm of signing keys and issued signatures.
21374 @item @code{ksk-size} (default: @code{256})
21375 The length of the KSK. Note that this value is correct for the default
21376 algorithm, but would be unsecure for other algorithms.
21378 @item @code{zsk-size} (default: @code{256})
21379 The length of the ZSK. Note that this value is correct for the default
21380 algorithm, but would be unsecure for other algorithms.
21382 @item @code{dnskey-ttl} (default: @code{'default})
21383 The TTL value for DNSKEY records added into zone apex. The special
21384 @code{'default} value means same as the zone SOA TTL.
21386 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
21387 The period between ZSK publication and the next rollover initiation.
21389 @item @code{propagation-delay} (default: @code{(* 24 3600)})
21390 An extra delay added for each key rollover step. This value should be high
21391 enough to cover propagation of data from the master server to all slaves.
21393 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
21394 A validity period of newly issued signatures.
21396 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
21397 A period how long before a signature expiration the signature will be refreshed.
21399 @item @code{nsec3?} (default: @code{#f})
21400 When @code{#t}, NSEC3 will be used instead of NSEC.
21402 @item @code{nsec3-iterations} (default: @code{5})
21403 The number of additional times the hashing is performed.
21405 @item @code{nsec3-salt-length} (default: @code{8})
21406 The length of a salt field in octets, which is appended to the original owner
21407 name before hashing.
21409 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
21410 The validity period of newly issued salt field.
21415 @deftp {Data Type} knot-zone-configuration
21416 Data type representing a zone served by Knot.
21417 This type has the following parameters:
21420 @item @code{domain} (default: @code{""})
21421 The domain served by this configuration. It must not be empty.
21423 @item @code{file} (default: @code{""})
21424 The file where this zone is saved. This parameter is ignored by master zones.
21425 Empty means default location that depends on the domain name.
21427 @item @code{zone} (default: @code{(zone-file)})
21428 The content of the zone file. This parameter is ignored by slave zones. It
21429 must contain a zone-file record.
21431 @item @code{master} (default: @code{'()})
21432 A list of master remotes. When empty, this zone is a master. When set, this
21433 zone is a slave. This is a list of remotes identifiers.
21435 @item @code{ddns-master} (default: @code{#f})
21436 The main master. When empty, it defaults to the first master in the list of
21439 @item @code{notify} (default: @code{'()})
21440 A list of slave remote identifiers.
21442 @item @code{acl} (default: @code{'()})
21443 A list of acl identifiers.
21445 @item @code{semantic-checks?} (default: @code{#f})
21446 When set, this adds more semantic checks to the zone.
21448 @item @code{disable-any?} (default: @code{#f})
21449 When set, this forbids queries of the ANY type.
21451 @item @code{zonefile-sync} (default: @code{0})
21452 The delay between a modification in memory and on disk. 0 means immediate
21455 @item @code{zonefile-load} (default: @code{#f})
21456 The way the zone file contents are applied during zone load. Possible values
21460 @item @code{#f} for using the default value from Knot,
21461 @item @code{'none} for not using the zone file at all,
21462 @item @code{'difference} for computing the difference between already available
21463 contents and zone contents and applying it to the current zone contents,
21464 @item @code{'difference-no-serial} for the same as @code{'difference}, but
21465 ignoring the SOA serial in the zone file, while the server takes care of it
21467 @item @code{'whole} for loading zone contents from the zone file.
21470 @item @code{journal-content} (default: @code{#f})
21471 The way the journal is used to store zone and its changes. Possible values
21472 are @code{'none} to not use it at all, @code{'changes} to store changes and
21473 @code{'all} to store contents. @code{#f} does not set this option, so the
21474 default value from Knot is used.
21476 @item @code{max-journal-usage} (default: @code{#f})
21477 The maximum size for the journal on disk. @code{#f} does not set this option,
21478 so the default value from Knot is used.
21480 @item @code{max-journal-depth} (default: @code{#f})
21481 The maximum size of the history. @code{#f} does not set this option, so the
21482 default value from Knot is used.
21484 @item @code{max-zone-size} (default: @code{#f})
21485 The maximum size of the zone file. This limit is enforced for incoming
21486 transfer and updates. @code{#f} does not set this option, so the default
21487 value from Knot is used.
21489 @item @code{dnssec-policy} (default: @code{#f})
21490 A reference to a @code{knot-policy-configuration} record, or the special
21491 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
21494 @item @code{serial-policy} (default: @code{'increment})
21495 A policy between @code{'increment} and @code{'unixtime}.
21500 @deftp {Data Type} knot-configuration
21501 Data type representing the Knot configuration.
21502 This type has the following parameters:
21505 @item @code{knot} (default: @code{knot})
21508 @item @code{run-directory} (default: @code{"/var/run/knot"})
21509 The run directory. This directory will be used for pid file and sockets.
21511 @item @code{includes} (default: @code{'()})
21512 A list of strings or file-like objects denoting other files that must be
21513 included at the top of the configuration file.
21515 @cindex secrets, Knot service
21516 This can be used to manage secrets out-of-band. For example, secret
21517 keys may be stored in an out-of-band file not managed by Guix, and
21518 thus not visible in @file{/gnu/store}---e.g., you could store secret
21519 key configuration in @file{/etc/knot/secrets.conf} and add this file
21520 to the @code{includes} list.
21522 One can generate a secret tsig key (for nsupdate and zone transfers with the
21523 keymgr command from the knot package. Note that the package is not automatically
21524 installed by the service. The following example shows how to generate a new
21528 keymgr -t mysecret > /etc/knot/secrets.conf
21529 chmod 600 /etc/knot/secrets.conf
21532 Also note that the generated key will be named @var{mysecret}, so it is the
21533 name that needs to be used in the @var{key} field of the
21534 @code{knot-acl-configuration} record and in other places that need to refer
21537 It can also be used to add configuration not supported by this interface.
21539 @item @code{listen-v4} (default: @code{"0.0.0.0"})
21540 An ip address on which to listen.
21542 @item @code{listen-v6} (default: @code{"::"})
21543 An ip address on which to listen.
21545 @item @code{listen-port} (default: @code{53})
21546 A port on which to listen.
21548 @item @code{keys} (default: @code{'()})
21549 The list of knot-key-configuration used by this configuration.
21551 @item @code{acls} (default: @code{'()})
21552 The list of knot-acl-configuration used by this configuration.
21554 @item @code{remotes} (default: @code{'()})
21555 The list of knot-remote-configuration used by this configuration.
21557 @item @code{zones} (default: @code{'()})
21558 The list of knot-zone-configuration used by this configuration.
21563 @subsubheading Knot Resolver Service
21565 @deffn {Scheme Variable} knot-resolver-service-type
21566 This this the type of the knot resolver service, whose value should be
21567 an @code{knot-resolver-configuration} object as in this example:
21570 (service knot-resolver-service-type
21571 (knot-resolver-configuration
21572 (kresd-config-file (plain-file "kresd.conf" "
21573 net.listen('192.168.0.1', 5353)
21574 user('knot-resolver', 'knot-resolver')
21575 modules = @{ 'hints > iterate', 'stats', 'predict' @}
21576 cache.size = 100 * MB
21580 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
21583 @deftp {Data Type} knot-resolver-configuration
21584 Data type representing the configuration of knot-resolver.
21587 @item @code{package} (default: @var{knot-resolver})
21588 Package object of the knot DNS resolver.
21590 @item @code{kresd-config-file} (default: %kresd.conf)
21591 File-like object of the kresd configuration file to use, by default it
21592 will listen on @code{127.0.0.1} and @code{::1}.
21594 @item @code{garbage-collection-interval} (default: 1000)
21595 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
21601 @subsubheading Dnsmasq Service
21603 @deffn {Scheme Variable} dnsmasq-service-type
21604 This is the type of the dnsmasq service, whose value should be an
21605 @code{dnsmasq-configuration} object as in this example:
21608 (service dnsmasq-service-type
21609 (dnsmasq-configuration
21611 (servers '("192.168.1.1"))))
21615 @deftp {Data Type} dnsmasq-configuration
21616 Data type representing the configuration of dnsmasq.
21619 @item @code{package} (default: @var{dnsmasq})
21620 Package object of the dnsmasq server.
21622 @item @code{no-hosts?} (default: @code{#f})
21623 When true, don't read the hostnames in /etc/hosts.
21625 @item @code{port} (default: @code{53})
21626 The port to listen on. Setting this to zero completely disables DNS
21627 responses, leaving only DHCP and/or TFTP functions.
21629 @item @code{local-service?} (default: @code{#t})
21630 Accept DNS queries only from hosts whose address is on a local subnet,
21631 ie a subnet for which an interface exists on the server.
21633 @item @code{listen-addresses} (default: @code{'()})
21634 Listen on the given IP addresses.
21636 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
21637 The file to read the IP address of the upstream nameservers from.
21639 @item @code{no-resolv?} (default: @code{#f})
21640 When true, don't read @var{resolv-file}.
21642 @item @code{servers} (default: @code{'()})
21643 Specify IP address of upstream servers directly.
21645 @item @code{cache-size} (default: @code{150})
21646 Set the size of dnsmasq's cache. Setting the cache size to zero
21649 @item @code{negative-cache?} (default: @code{#t})
21650 When false, disable negative caching.
21655 @subsubheading ddclient Service
21658 The ddclient service described below runs the ddclient daemon, which takes
21659 care of automatically updating DNS entries for service providers such as
21660 @uref{https://dyn.com/dns/, Dyn}.
21662 The following example show instantiates the service with its default
21666 (service ddclient-service-type)
21669 Note that ddclient needs to access credentials that are stored in a
21670 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
21671 @code{secret-file} below.) You are expected to create this file manually, in
21672 an ``out-of-band'' fashion (you @emph{could} make this file part of the
21673 service configuration, for instance by using @code{plain-file}, but it will be
21674 world-readable @i{via} @file{/gnu/store}.) See the examples in the
21675 @file{share/ddclient} directory of the @code{ddclient} package.
21677 @c %start of fragment
21679 Available @code{ddclient-configuration} fields are:
21681 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
21682 The ddclient package.
21686 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
21687 The period after which ddclient will retry to check IP and domain name.
21689 Defaults to @samp{300}.
21693 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
21694 Use syslog for the output.
21696 Defaults to @samp{#t}.
21700 @deftypevr {@code{ddclient-configuration} parameter} string mail
21703 Defaults to @samp{"root"}.
21707 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
21708 Mail failed update to user.
21710 Defaults to @samp{"root"}.
21714 @deftypevr {@code{ddclient-configuration} parameter} string pid
21715 The ddclient PID file.
21717 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
21721 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
21722 Enable SSL support.
21724 Defaults to @samp{#t}.
21728 @deftypevr {@code{ddclient-configuration} parameter} string user
21729 Specifies the user name or ID that is used when running ddclient
21732 Defaults to @samp{"ddclient"}.
21736 @deftypevr {@code{ddclient-configuration} parameter} string group
21737 Group of the user who will run the ddclient program.
21739 Defaults to @samp{"ddclient"}.
21743 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
21744 Secret file which will be appended to @file{ddclient.conf} file. This
21745 file contains credentials for use by ddclient. You are expected to
21746 create it manually.
21748 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
21752 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
21753 Extra options will be appended to @file{ddclient.conf} file.
21755 Defaults to @samp{()}.
21760 @c %end of fragment
21764 @subsection VPN Services
21765 @cindex VPN (virtual private network)
21766 @cindex virtual private network (VPN)
21768 The @code{(gnu services vpn)} module provides services related to
21769 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
21770 your machine to connect to a VPN, and a @emph{server} service for your machine
21771 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
21773 @deffn {Scheme Procedure} openvpn-client-service @
21774 [#:config (openvpn-client-configuration)]
21776 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
21779 @deffn {Scheme Procedure} openvpn-server-service @
21780 [#:config (openvpn-server-configuration)]
21782 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
21784 Both can be run simultaneously.
21787 @c %automatically generated documentation
21789 Available @code{openvpn-client-configuration} fields are:
21791 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
21792 The OpenVPN package.
21796 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
21797 The OpenVPN pid file.
21799 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21803 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
21804 The protocol (UDP or TCP) used to open a channel between clients and
21807 Defaults to @samp{udp}.
21811 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
21812 The device type used to represent the VPN connection.
21814 Defaults to @samp{tun}.
21818 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
21819 The certificate authority to check connections against.
21821 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21825 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
21826 The certificate of the machine the daemon is running on. It should be
21827 signed by the authority given in @code{ca}.
21829 Defaults to @samp{"/etc/openvpn/client.crt"}.
21833 @deftypevr {@code{openvpn-client-configuration} parameter} string key
21834 The key of the machine the daemon is running on. It must be the key whose
21835 certificate is @code{cert}.
21837 Defaults to @samp{"/etc/openvpn/client.key"}.
21841 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
21842 Whether to use the lzo compression algorithm.
21844 Defaults to @samp{#t}.
21848 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
21849 Don't re-read key files across SIGUSR1 or --ping-restart.
21851 Defaults to @samp{#t}.
21855 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
21856 Don't close and reopen TUN/TAP device or run up/down scripts across
21857 SIGUSR1 or --ping-restart restarts.
21859 Defaults to @samp{#t}.
21863 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
21864 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
21865 poll/epoll/select prior to the write operation.
21867 Defaults to @samp{#f}.
21870 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
21873 Defaults to @samp{3}.
21877 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
21878 Add an additional layer of HMAC authentication on top of the TLS control
21879 channel to protect against DoS attacks.
21881 Defaults to @samp{#f}.
21885 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
21886 Authenticate with server using username/password. The option is a file
21887 containing username/password on 2 lines. Do not use a file-like object as it
21888 would be added to the store and readable by any user.
21890 Defaults to @samp{'disabled}.
21893 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
21894 Whether to check the server certificate has server usage extension.
21896 Defaults to @samp{#t}.
21900 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
21901 Bind to a specific local port number.
21903 Defaults to @samp{#f}.
21907 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
21908 Retry resolving server address.
21910 Defaults to @samp{#t}.
21914 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
21915 A list of remote servers to connect to.
21917 Defaults to @samp{()}.
21919 Available @code{openvpn-remote-configuration} fields are:
21921 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
21924 Defaults to @samp{"my-server"}.
21928 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
21929 Port number the server listens to.
21931 Defaults to @samp{1194}.
21936 @c %end of automatic openvpn-client documentation
21938 @c %automatically generated documentation
21940 Available @code{openvpn-server-configuration} fields are:
21942 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
21943 The OpenVPN package.
21947 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
21948 The OpenVPN pid file.
21950 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21954 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
21955 The protocol (UDP or TCP) used to open a channel between clients and
21958 Defaults to @samp{udp}.
21962 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
21963 The device type used to represent the VPN connection.
21965 Defaults to @samp{tun}.
21969 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
21970 The certificate authority to check connections against.
21972 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21976 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
21977 The certificate of the machine the daemon is running on. It should be
21978 signed by the authority given in @code{ca}.
21980 Defaults to @samp{"/etc/openvpn/client.crt"}.
21984 @deftypevr {@code{openvpn-server-configuration} parameter} string key
21985 The key of the machine the daemon is running on. It must be the key whose
21986 certificate is @code{cert}.
21988 Defaults to @samp{"/etc/openvpn/client.key"}.
21992 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
21993 Whether to use the lzo compression algorithm.
21995 Defaults to @samp{#t}.
21999 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
22000 Don't re-read key files across SIGUSR1 or --ping-restart.
22002 Defaults to @samp{#t}.
22006 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
22007 Don't close and reopen TUN/TAP device or run up/down scripts across
22008 SIGUSR1 or --ping-restart restarts.
22010 Defaults to @samp{#t}.
22014 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
22015 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22016 poll/epoll/select prior to the write operation.
22018 Defaults to @samp{#f}.
22021 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
22024 Defaults to @samp{3}.
22028 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
22029 Add an additional layer of HMAC authentication on top of the TLS control
22030 channel to protect against DoS attacks.
22032 Defaults to @samp{#f}.
22036 @deftypevr {@code{openvpn-server-configuration} parameter} number port
22037 Specifies the port number on which the server listens.
22039 Defaults to @samp{1194}.
22043 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
22044 An ip and mask specifying the subnet inside the virtual network.
22046 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
22050 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
22051 A CIDR notation specifying the IPv6 subnet inside the virtual network.
22053 Defaults to @samp{#f}.
22057 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
22058 The Diffie-Hellman parameters file.
22060 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
22064 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
22065 The file that records client IPs.
22067 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
22071 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
22072 When true, the server will act as a gateway for its clients.
22074 Defaults to @samp{#f}.
22078 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
22079 When true, clients are allowed to talk to each other inside the VPN.
22081 Defaults to @samp{#f}.
22085 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
22086 Causes ping-like messages to be sent back and forth over the link so
22087 that each side knows when the other side has gone down. @code{keepalive}
22088 requires a pair. The first element is the period of the ping sending,
22089 and the second element is the timeout before considering the other side
22094 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
22095 The maximum number of clients.
22097 Defaults to @samp{100}.
22101 @deftypevr {@code{openvpn-server-configuration} parameter} string status
22102 The status file. This file shows a small report on current connection.
22103 It is truncated and rewritten every minute.
22105 Defaults to @samp{"/var/run/openvpn/status"}.
22109 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
22110 The list of configuration for some clients.
22112 Defaults to @samp{()}.
22114 Available @code{openvpn-ccd-configuration} fields are:
22116 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
22119 Defaults to @samp{"client"}.
22123 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
22126 Defaults to @samp{#f}.
22130 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
22133 Defaults to @samp{#f}.
22140 @c %end of automatic openvpn-server documentation
22143 @node Network File System
22144 @subsection Network File System
22147 The @code{(gnu services nfs)} module provides the following services,
22148 which are most commonly used in relation to mounting or exporting
22149 directory trees as @dfn{network file systems} (NFS).
22151 While it is possible to use the individual components that together make
22152 up a Network File System service, we recommended to configure an NFS
22153 server with the @code{nfs-service-type}.
22155 @subsubheading NFS Service
22156 @cindex NFS, server
22158 The NFS service takes care of setting up all NFS component services,
22159 kernel configuration file systems, and installs configuration files in
22160 the locations that NFS expects.
22162 @defvr {Scheme Variable} nfs-service-type
22163 A service type for a complete NFS server.
22166 @deftp {Data Type} nfs-configuration
22167 This data type represents the configuration of the NFS service and all
22170 It has the following parameters:
22172 @item @code{nfs-utils} (default: @code{nfs-utils})
22173 The nfs-utils package to use.
22175 @item @code{nfs-version} (default: @code{#f})
22176 If a string value is provided, the @command{rpc.nfsd} daemon will be
22177 limited to supporting the given version of the NFS protocol.
22179 @item @code{exports} (default: @code{'()})
22180 This is a list of directories the NFS server should export. Each entry
22181 is a list consisting of two elements: a directory name and a string
22182 containing all options. This is an example in which the directory
22183 @file{/export} is served to all NFS clients as a read-only share:
22189 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
22192 @item @code{rpcmountd-port} (default: @code{#f})
22193 The network port that the @command{rpc.mountd} daemon should use.
22195 @item @code{rpcstatd-port} (default: @code{#f})
22196 The network port that the @command{rpc.statd} daemon should use.
22198 @item @code{rpcbind} (default: @code{rpcbind})
22199 The rpcbind package to use.
22201 @item @code{idmap-domain} (default: @code{"localdomain"})
22202 The local NFSv4 domain name.
22204 @item @code{nfsd-port} (default: @code{2049})
22205 The network port that the @command{nfsd} daemon should use.
22207 @item @code{nfsd-threads} (default: @code{8})
22208 The number of threads used by the @command{nfsd} daemon.
22210 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22211 The directory where the pipefs file system is mounted.
22213 @item @code{debug} (default: @code{'()"})
22214 A list of subsystems for which debugging output should be enabled. This
22215 is a list of symbols. Any of these symbols are valid: @code{nfsd},
22216 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
22220 If you don't need a complete NFS service or prefer to build it yourself
22221 you can use the individual component services that are documented below.
22223 @subsubheading RPC Bind Service
22226 The RPC Bind service provides a facility to map program numbers into
22227 universal addresses.
22228 Many NFS related services use this facility. Hence it is automatically
22229 started when a dependent service starts.
22231 @defvr {Scheme Variable} rpcbind-service-type
22232 A service type for the RPC portmapper daemon.
22236 @deftp {Data Type} rpcbind-configuration
22237 Data type representing the configuration of the RPC Bind Service.
22238 This type has the following parameters:
22240 @item @code{rpcbind} (default: @code{rpcbind})
22241 The rpcbind package to use.
22243 @item @code{warm-start?} (default: @code{#t})
22244 If this parameter is @code{#t}, then the daemon will read a
22245 state file on startup thus reloading state information saved by a previous
22251 @subsubheading Pipefs Pseudo File System
22255 The pipefs file system is used to transfer NFS related data
22256 between the kernel and user space programs.
22258 @defvr {Scheme Variable} pipefs-service-type
22259 A service type for the pipefs pseudo file system.
22262 @deftp {Data Type} pipefs-configuration
22263 Data type representing the configuration of the pipefs pseudo file system service.
22264 This type has the following parameters:
22266 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22267 The directory to which the file system is to be attached.
22272 @subsubheading GSS Daemon Service
22275 @cindex global security system
22277 The @dfn{global security system} (GSS) daemon provides strong security for RPC
22279 Before exchanging RPC requests an RPC client must establish a security
22280 context. Typically this is done using the Kerberos command @command{kinit}
22281 or automatically at login time using PAM services (@pxref{Kerberos Services}).
22283 @defvr {Scheme Variable} gss-service-type
22284 A service type for the Global Security System (GSS) daemon.
22287 @deftp {Data Type} gss-configuration
22288 Data type representing the configuration of the GSS daemon service.
22289 This type has the following parameters:
22291 @item @code{nfs-utils} (default: @code{nfs-utils})
22292 The package in which the @command{rpc.gssd} command is to be found.
22294 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22295 The directory where the pipefs file system is mounted.
22301 @subsubheading IDMAP Daemon Service
22303 @cindex name mapper
22305 The idmap daemon service provides mapping between user IDs and user names.
22306 Typically it is required in order to access file systems mounted via NFSv4.
22308 @defvr {Scheme Variable} idmap-service-type
22309 A service type for the Identity Mapper (IDMAP) daemon.
22312 @deftp {Data Type} idmap-configuration
22313 Data type representing the configuration of the IDMAP daemon service.
22314 This type has the following parameters:
22316 @item @code{nfs-utils} (default: @code{nfs-utils})
22317 The package in which the @command{rpc.idmapd} command is to be found.
22319 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22320 The directory where the pipefs file system is mounted.
22322 @item @code{domain} (default: @code{#f})
22323 The local NFSv4 domain name.
22324 This must be a string or @code{#f}.
22325 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
22327 @item @code{verbosity} (default: @code{0})
22328 The verbosity level of the daemon.
22333 @node Continuous Integration
22334 @subsection Continuous Integration
22336 @cindex continuous integration
22337 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
22338 continuous integration tool for Guix. It can be used both for development and
22339 for providing substitutes to others (@pxref{Substitutes}).
22341 The @code{(gnu services cuirass)} module provides the following service.
22343 @defvr {Scheme Procedure} cuirass-service-type
22344 The type of the Cuirass service. Its value must be a
22345 @code{cuirass-configuration} object, as described below.
22348 To add build jobs, you have to set the @code{specifications} field of the
22349 configuration. Here is an example of a service that polls the Guix repository
22350 and builds the packages from a manifest. Some of the packages are defined in
22351 the @code{"custom-packages"} input, which is the equivalent of
22352 @code{GUIX_PACKAGE_PATH}.
22355 (define %cuirass-specs
22357 '((#:name . "my-manifest")
22358 (#:load-path-inputs . ("guix"))
22359 (#:package-path-inputs . ("custom-packages"))
22360 (#:proc-input . "guix")
22361 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
22362 (#:proc . cuirass-jobs)
22363 (#:proc-args . ((subset . "manifests")
22364 (systems . ("x86_64-linux"))
22365 (manifests . (("config" . "guix/manifest.scm")))))
22366 (#:inputs . (((#:name . "guix")
22367 (#:url . "git://git.savannah.gnu.org/guix.git")
22368 (#:load-path . ".")
22369 (#:branch . "master")
22370 (#:no-compile? . #t))
22371 ((#:name . "config")
22372 (#:url . "https://git.example.org/config.git")
22373 (#:load-path . ".")
22374 (#:branch . "master")
22375 (#:no-compile? . #t))
22376 ((#:name . "custom-packages")
22377 (#:url . "https://git.example.org/custom-packages.git")
22378 (#:load-path . ".")
22379 (#:branch . "master")
22380 (#:no-compile? . #t)))))))
22382 (service cuirass-service-type
22383 (cuirass-configuration
22384 (specifications %cuirass-specs)))
22387 While information related to build jobs is located directly in the
22388 specifications, global settings for the @command{cuirass} process are
22389 accessible in other @code{cuirass-configuration} fields.
22391 @deftp {Data Type} cuirass-configuration
22392 Data type representing the configuration of Cuirass.
22395 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
22396 Location of the log file.
22398 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
22399 Location of the log file used by the web interface.
22401 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
22402 Location of the repository cache.
22404 @item @code{user} (default: @code{"cuirass"})
22405 Owner of the @code{cuirass} process.
22407 @item @code{group} (default: @code{"cuirass"})
22408 Owner's group of the @code{cuirass} process.
22410 @item @code{interval} (default: @code{60})
22411 Number of seconds between the poll of the repositories followed by the
22414 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
22415 Location of sqlite database which contains the build results and previously
22416 added specifications.
22418 @item @code{ttl} (default: @code{(* 30 24 3600)})
22419 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
22420 are registered for build results. This means that build results are protected
22421 from garbage collection for at least @var{ttl} seconds.
22423 @item @code{port} (default: @code{8081})
22424 Port number used by the HTTP server.
22426 @item @code{host} (default: @code{"localhost"})
22427 Listen on the network interface for @var{host}. The default is to
22428 accept connections from localhost.
22430 @item @code{specifications} (default: @code{#~'()})
22431 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
22432 where a specification is an association list
22433 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
22434 keys are keywords (@code{#:keyword-example}) as shown in the example
22437 @item @code{use-substitutes?} (default: @code{#f})
22438 This allows using substitutes to avoid building every dependencies of a job
22441 @item @code{one-shot?} (default: @code{#f})
22442 Only evaluate specifications and build derivations once.
22444 @item @code{fallback?} (default: @code{#f})
22445 When substituting a pre-built binary fails, fall back to building
22448 @item @code{cuirass} (default: @code{cuirass})
22449 The Cuirass package to use.
22453 @node Power Management Services
22454 @subsection Power Management Services
22457 @cindex power management with TLP
22458 @subsubheading TLP daemon
22460 The @code{(gnu services pm)} module provides a Guix service definition
22461 for the Linux power management tool TLP.
22463 TLP enables various powersaving modes in userspace and kernel.
22464 Contrary to @code{upower-service}, it is not a passive,
22465 monitoring tool, as it will apply custom settings each time a new power
22466 source is detected. More information can be found at
22467 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
22469 @deffn {Scheme Variable} tlp-service-type
22470 The service type for the TLP tool. Its value should be a valid
22471 TLP configuration (see below). To use the default settings, simply
22474 (service tlp-service-type)
22478 By default TLP does not need much configuration but most TLP parameters
22479 can be tweaked using @code{tlp-configuration}.
22481 Each parameter definition is preceded by its type; for example,
22482 @samp{boolean foo} indicates that the @code{foo} parameter
22483 should be specified as a boolean. Types starting with
22484 @code{maybe-} denote parameters that won't show up in TLP config file
22485 when their value is @code{'disabled}.
22487 @c The following documentation was initially generated by
22488 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
22489 @c documentation is better, so we shouldn't hesitate to edit below as
22490 @c needed. However if the change you want to make to this documentation
22491 @c can be done in an automated way, it's probably easier to change
22492 @c (generate-documentation) than to make it below and have to deal with
22493 @c the churn as TLP updates.
22495 Available @code{tlp-configuration} fields are:
22497 @deftypevr {@code{tlp-configuration} parameter} package tlp
22502 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
22503 Set to true if you wish to enable TLP.
22505 Defaults to @samp{#t}.
22509 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
22510 Default mode when no power supply can be detected. Alternatives are AC
22513 Defaults to @samp{"AC"}.
22517 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
22518 Number of seconds Linux kernel has to wait after the disk goes idle,
22519 before syncing on AC.
22521 Defaults to @samp{0}.
22525 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
22526 Same as @code{disk-idle-ac} but on BAT mode.
22528 Defaults to @samp{2}.
22532 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
22533 Dirty pages flushing periodicity, expressed in seconds.
22535 Defaults to @samp{15}.
22539 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
22540 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
22542 Defaults to @samp{60}.
22546 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
22547 CPU frequency scaling governor on AC mode. With intel_pstate driver,
22548 alternatives are powersave and performance. With acpi-cpufreq driver,
22549 alternatives are ondemand, powersave, performance and conservative.
22551 Defaults to @samp{disabled}.
22555 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
22556 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
22558 Defaults to @samp{disabled}.
22562 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
22563 Set the min available frequency for the scaling governor on AC.
22565 Defaults to @samp{disabled}.
22569 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
22570 Set the max available frequency for the scaling governor on AC.
22572 Defaults to @samp{disabled}.
22576 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
22577 Set the min available frequency for the scaling governor on BAT.
22579 Defaults to @samp{disabled}.
22583 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
22584 Set the max available frequency for the scaling governor on BAT.
22586 Defaults to @samp{disabled}.
22590 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
22591 Limit the min P-state to control the power dissipation of the CPU, in AC
22592 mode. Values are stated as a percentage of the available performance.
22594 Defaults to @samp{disabled}.
22598 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
22599 Limit the max P-state to control the power dissipation of the CPU, in AC
22600 mode. Values are stated as a percentage of the available performance.
22602 Defaults to @samp{disabled}.
22606 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
22607 Same as @code{cpu-min-perf-on-ac} on BAT mode.
22609 Defaults to @samp{disabled}.
22613 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
22614 Same as @code{cpu-max-perf-on-ac} on BAT mode.
22616 Defaults to @samp{disabled}.
22620 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
22621 Enable CPU turbo boost feature on AC mode.
22623 Defaults to @samp{disabled}.
22627 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
22628 Same as @code{cpu-boost-on-ac?} on BAT mode.
22630 Defaults to @samp{disabled}.
22634 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
22635 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
22636 used under light load conditions.
22638 Defaults to @samp{#f}.
22642 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
22643 Same as @code{sched-powersave-on-ac?} but on BAT mode.
22645 Defaults to @samp{#t}.
22649 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
22650 Enable Linux kernel NMI watchdog.
22652 Defaults to @samp{#f}.
22656 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
22657 For Linux kernels with PHC patch applied, change CPU voltages. An
22658 example value would be @samp{"F:V F:V F:V F:V"}.
22660 Defaults to @samp{disabled}.
22664 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
22665 Set CPU performance versus energy saving policy on AC. Alternatives are
22666 performance, normal, powersave.
22668 Defaults to @samp{"performance"}.
22672 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
22673 Same as @code{energy-perf-policy-ac} but on BAT mode.
22675 Defaults to @samp{"powersave"}.
22679 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
22684 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
22685 Hard disk advanced power management level.
22689 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
22690 Same as @code{disk-apm-bat} but on BAT mode.
22694 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
22695 Hard disk spin down timeout. One value has to be specified for each
22696 declared hard disk.
22698 Defaults to @samp{disabled}.
22702 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
22703 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
22705 Defaults to @samp{disabled}.
22709 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
22710 Select IO scheduler for disk devices. One value has to be specified for
22711 each declared hard disk. Example alternatives are cfq, deadline and
22714 Defaults to @samp{disabled}.
22718 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
22719 SATA aggressive link power management (ALPM) level. Alternatives are
22720 min_power, medium_power, max_performance.
22722 Defaults to @samp{"max_performance"}.
22726 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
22727 Same as @code{sata-linkpwr-ac} but on BAT mode.
22729 Defaults to @samp{"min_power"}.
22733 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
22734 Exclude specified SATA host devices for link power management.
22736 Defaults to @samp{disabled}.
22740 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
22741 Enable Runtime Power Management for AHCI controller and disks on AC
22744 Defaults to @samp{disabled}.
22748 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
22749 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
22751 Defaults to @samp{disabled}.
22755 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
22756 Seconds of inactivity before disk is suspended.
22758 Defaults to @samp{15}.
22762 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
22763 PCI Express Active State Power Management level. Alternatives are
22764 default, performance, powersave.
22766 Defaults to @samp{"performance"}.
22770 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
22771 Same as @code{pcie-aspm-ac} but on BAT mode.
22773 Defaults to @samp{"powersave"}.
22777 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
22778 Radeon graphics clock speed level. Alternatives are low, mid, high,
22781 Defaults to @samp{"high"}.
22785 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
22786 Same as @code{radeon-power-ac} but on BAT mode.
22788 Defaults to @samp{"low"}.
22792 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
22793 Radeon dynamic power management method (DPM). Alternatives are battery,
22796 Defaults to @samp{"performance"}.
22800 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
22801 Same as @code{radeon-dpm-state-ac} but on BAT mode.
22803 Defaults to @samp{"battery"}.
22807 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
22808 Radeon DPM performance level. Alternatives are auto, low, high.
22810 Defaults to @samp{"auto"}.
22814 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
22815 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
22817 Defaults to @samp{"auto"}.
22821 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
22822 Wifi power saving mode.
22824 Defaults to @samp{#f}.
22828 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
22829 Same as @code{wifi-power-ac?} but on BAT mode.
22831 Defaults to @samp{#t}.
22835 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
22836 Disable wake on LAN.
22838 Defaults to @samp{#t}.
22842 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
22843 Timeout duration in seconds before activating audio power saving on
22844 Intel HDA and AC97 devices. A value of 0 disables power saving.
22846 Defaults to @samp{0}.
22850 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
22851 Same as @code{sound-powersave-ac} but on BAT mode.
22853 Defaults to @samp{1}.
22857 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
22858 Disable controller in powersaving mode on Intel HDA devices.
22860 Defaults to @samp{#t}.
22864 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
22865 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
22866 powered on again by releasing (and reinserting) the eject lever or by
22867 pressing the disc eject button on newer models.
22869 Defaults to @samp{#f}.
22873 @deftypevr {@code{tlp-configuration} parameter} string bay-device
22874 Name of the optical drive device to power off.
22876 Defaults to @samp{"sr0"}.
22880 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
22881 Runtime Power Management for PCI(e) bus devices. Alternatives are on
22884 Defaults to @samp{"on"}.
22888 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
22889 Same as @code{runtime-pm-ac} but on BAT mode.
22891 Defaults to @samp{"auto"}.
22895 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
22896 Runtime Power Management for all PCI(e) bus devices, except blacklisted
22899 Defaults to @samp{#t}.
22903 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
22904 Exclude specified PCI(e) device addresses from Runtime Power Management.
22906 Defaults to @samp{disabled}.
22910 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
22911 Exclude PCI(e) devices assigned to the specified drivers from Runtime
22916 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
22917 Enable USB autosuspend feature.
22919 Defaults to @samp{#t}.
22923 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
22924 Exclude specified devices from USB autosuspend.
22926 Defaults to @samp{disabled}.
22930 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
22931 Exclude WWAN devices from USB autosuspend.
22933 Defaults to @samp{#t}.
22937 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
22938 Include specified devices into USB autosuspend, even if they are already
22939 excluded by the driver or via @code{usb-blacklist-wwan?}.
22941 Defaults to @samp{disabled}.
22945 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
22946 Enable USB autosuspend before shutdown.
22948 Defaults to @samp{disabled}.
22952 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
22953 Restore radio device state (bluetooth, wifi, wwan) from previous
22954 shutdown on system startup.
22956 Defaults to @samp{#f}.
22961 @cindex CPU frequency scaling with thermald
22962 @subsubheading Thermald daemon
22964 The @code{(gnu services pm)} module provides an interface to
22965 thermald, a CPU frequency scaling service which helps prevent overheating.
22967 @defvr {Scheme Variable} thermald-service-type
22968 This is the service type for
22969 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
22970 Thermal Daemon, which is responsible for controlling the thermal state
22971 of processors and preventing overheating.
22974 @deftp {Data Type} thermald-configuration
22975 Data type representing the configuration of @code{thermald-service-type}.
22978 @item @code{ignore-cpuid-check?} (default: @code{#f})
22979 Ignore cpuid check for supported CPU models.
22981 @item @code{thermald} (default: @var{thermald})
22982 Package object of thermald.
22987 @node Audio Services
22988 @subsection Audio Services
22990 The @code{(gnu services audio)} module provides a service to start MPD
22991 (the Music Player Daemon).
22994 @subsubheading Music Player Daemon
22996 The Music Player Daemon (MPD) is a service that can play music while
22997 being controlled from the local machine or over the network by a variety
23000 The following example shows how one might run @code{mpd} as user
23001 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
23004 (service mpd-service-type
23010 @defvr {Scheme Variable} mpd-service-type
23011 The service type for @command{mpd}
23014 @deftp {Data Type} mpd-configuration
23015 Data type representing the configuration of @command{mpd}.
23018 @item @code{user} (default: @code{"mpd"})
23019 The user to run mpd as.
23021 @item @code{music-dir} (default: @code{"~/Music"})
23022 The directory to scan for music files.
23024 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
23025 The directory to store playlists.
23027 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
23028 The location of the music database.
23030 @item @code{state-file} (default: @code{"~/.mpd/state"})
23031 The location of the file that stores current MPD's state.
23033 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
23034 The location of the sticker database.
23036 @item @code{port} (default: @code{"6600"})
23037 The port to run mpd on.
23039 @item @code{address} (default: @code{"any"})
23040 The address that mpd will bind to. To use a Unix domain socket,
23041 an absolute path can be specified here.
23043 @item @code{outputs} (default: @code{"(list (mpd-output))"})
23044 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
23049 @deftp {Data Type} mpd-output
23050 Data type representing an @command{mpd} audio output.
23053 @item @code{name} (default: @code{"MPD"})
23054 The name of the audio output.
23056 @item @code{type} (default: @code{"pulse"})
23057 The type of audio output.
23059 @item @code{enabled?} (default: @code{#t})
23060 Specifies whether this audio output is enabled when MPD is started. By
23061 default, all audio outputs are enabled. This is just the default
23062 setting when there is no state file; with a state file, the previous
23065 @item @code{tags?} (default: @code{#t})
23066 If set to @code{#f}, then MPD will not send tags to this output. This
23067 is only useful for output plugins that can receive tags, for example the
23068 @code{httpd} output plugin.
23070 @item @code{always-on?} (default: @code{#f})
23071 If set to @code{#t}, then MPD attempts to keep this audio output always
23072 open. This may be useful for streaming servers, when you don’t want to
23073 disconnect all listeners even when playback is accidentally stopped.
23075 @item @code{mixer-type}
23076 This field accepts a symbol that specifies which mixer should be used
23077 for this audio output: the @code{hardware} mixer, the @code{software}
23078 mixer, the @code{null} mixer (allows setting the volume, but with no
23079 effect; this can be used as a trick to implement an external mixer
23080 External Mixer) or no mixer (@code{none}).
23082 @item @code{extra-options} (default: @code{'()"})
23083 An association list of option symbols to string values to be appended to
23084 the audio output configuration.
23089 The following example shows a configuration of @code{mpd} that provides
23090 an HTTP audio streaming output.
23093 (service mpd-service-type
23101 `((encoder . "vorbis")
23102 (port . "8080"))))))))
23106 @node Virtualization Services
23107 @subsection Virtualization services
23109 The @code{(gnu services virtualization)} module provides services for
23110 the libvirt and virtlog daemons, as well as other virtualization-related
23113 @subsubheading Libvirt daemon
23114 @code{libvirtd} is the server side daemon component of the libvirt
23115 virtualization management system. This daemon runs on host servers
23116 and performs required management tasks for virtualized guests.
23118 @deffn {Scheme Variable} libvirt-service-type
23119 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
23120 Its value must be a @code{libvirt-configuration}.
23123 (service libvirt-service-type
23124 (libvirt-configuration
23125 (unix-sock-group "libvirt")
23126 (tls-port "16555")))
23130 @c Auto-generated with (generate-libvirt-documentation)
23131 Available @code{libvirt-configuration} fields are:
23133 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
23138 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
23139 Flag listening for secure TLS connections on the public TCP/IP port.
23140 must set @code{listen} for this to have any effect.
23142 It is necessary to setup a CA and issue server certificates before using
23145 Defaults to @samp{#t}.
23149 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
23150 Listen for unencrypted TCP connections on the public TCP/IP port. must
23151 set @code{listen} for this to have any effect.
23153 Using the TCP socket requires SASL authentication by default. Only SASL
23154 mechanisms which support data encryption are allowed. This is
23155 DIGEST_MD5 and GSSAPI (Kerberos5)
23157 Defaults to @samp{#f}.
23161 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
23162 Port for accepting secure TLS connections This can be a port number, or
23165 Defaults to @samp{"16514"}.
23169 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
23170 Port for accepting insecure TCP connections This can be a port number,
23173 Defaults to @samp{"16509"}.
23177 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
23178 IP address or hostname used for client connections.
23180 Defaults to @samp{"0.0.0.0"}.
23184 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
23185 Flag toggling mDNS advertisement of the libvirt service.
23187 Alternatively can disable for all services on a host by stopping the
23190 Defaults to @samp{#f}.
23194 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
23195 Default mDNS advertisement name. This must be unique on the immediate
23198 Defaults to @samp{"Virtualization Host <hostname>"}.
23202 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
23203 UNIX domain socket group ownership. This can be used to allow a
23204 'trusted' set of users access to management capabilities without
23207 Defaults to @samp{"root"}.
23211 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
23212 UNIX socket permissions for the R/O socket. This is used for monitoring
23215 Defaults to @samp{"0777"}.
23219 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
23220 UNIX socket permissions for the R/W socket. Default allows only root.
23221 If PolicyKit is enabled on the socket, the default will change to allow
23222 everyone (eg, 0777)
23224 Defaults to @samp{"0770"}.
23228 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
23229 UNIX socket permissions for the admin socket. Default allows only owner
23230 (root), do not change it unless you are sure to whom you are exposing
23233 Defaults to @samp{"0777"}.
23237 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
23238 The directory in which sockets will be found/created.
23240 Defaults to @samp{"/var/run/libvirt"}.
23244 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
23245 Authentication scheme for UNIX read-only sockets. By default socket
23246 permissions allow anyone to connect
23248 Defaults to @samp{"polkit"}.
23252 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
23253 Authentication scheme for UNIX read-write sockets. By default socket
23254 permissions only allow root. If PolicyKit support was compiled into
23255 libvirt, the default will be to use 'polkit' auth.
23257 Defaults to @samp{"polkit"}.
23261 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
23262 Authentication scheme for TCP sockets. If you don't enable SASL, then
23263 all TCP traffic is cleartext. Don't do this outside of a dev/test
23266 Defaults to @samp{"sasl"}.
23270 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
23271 Authentication scheme for TLS sockets. TLS sockets already have
23272 encryption provided by the TLS layer, and limited authentication is done
23275 It is possible to make use of any SASL authentication mechanism as well,
23276 by using 'sasl' for this option
23278 Defaults to @samp{"none"}.
23282 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
23283 API access control scheme.
23285 By default an authenticated user is allowed access to all APIs. Access
23286 drivers can place restrictions on this.
23288 Defaults to @samp{()}.
23292 @deftypevr {@code{libvirt-configuration} parameter} string key-file
23293 Server key file path. If set to an empty string, then no private key is
23296 Defaults to @samp{""}.
23300 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
23301 Server key file path. If set to an empty string, then no certificate is
23304 Defaults to @samp{""}.
23308 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
23309 Server key file path. If set to an empty string, then no CA certificate
23312 Defaults to @samp{""}.
23316 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
23317 Certificate revocation list path. If set to an empty string, then no
23320 Defaults to @samp{""}.
23324 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
23325 Disable verification of our own server certificates.
23327 When libvirtd starts it performs some sanity checks against its own
23330 Defaults to @samp{#f}.
23334 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
23335 Disable verification of client certificates.
23337 Client certificate verification is the primary authentication mechanism.
23338 Any client which does not present a certificate signed by the CA will be
23341 Defaults to @samp{#f}.
23345 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
23346 Whitelist of allowed x509 Distinguished Name.
23348 Defaults to @samp{()}.
23352 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
23353 Whitelist of allowed SASL usernames. The format for username depends on
23354 the SASL authentication mechanism.
23356 Defaults to @samp{()}.
23360 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
23361 Override the compile time default TLS priority string. The default is
23362 usually "NORMAL" unless overridden at build time. Only set this is it
23363 is desired for libvirt to deviate from the global default settings.
23365 Defaults to @samp{"NORMAL"}.
23369 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
23370 Maximum number of concurrent client connections to allow over all
23373 Defaults to @samp{5000}.
23377 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
23378 Maximum length of queue of connections waiting to be accepted by the
23379 daemon. Note, that some protocols supporting retransmission may obey
23380 this so that a later reattempt at connection succeeds.
23382 Defaults to @samp{1000}.
23386 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
23387 Maximum length of queue of accepted but not yet authenticated clients.
23388 Set this to zero to turn this feature off
23390 Defaults to @samp{20}.
23394 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
23395 Number of workers to start up initially.
23397 Defaults to @samp{5}.
23401 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
23402 Maximum number of worker threads.
23404 If the number of active clients exceeds @code{min-workers}, then more
23405 threads are spawned, up to max_workers limit. Typically you'd want
23406 max_workers to equal maximum number of clients allowed.
23408 Defaults to @samp{20}.
23412 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
23413 Number of priority workers. If all workers from above pool are stuck,
23414 some calls marked as high priority (notably domainDestroy) can be
23415 executed in this pool.
23417 Defaults to @samp{5}.
23421 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
23422 Total global limit on concurrent RPC calls.
23424 Defaults to @samp{20}.
23428 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
23429 Limit on concurrent requests from a single client connection. To avoid
23430 one client monopolizing the server this should be a small fraction of
23431 the global max_requests and max_workers parameter.
23433 Defaults to @samp{5}.
23437 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
23438 Same as @code{min-workers} but for the admin interface.
23440 Defaults to @samp{1}.
23444 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
23445 Same as @code{max-workers} but for the admin interface.
23447 Defaults to @samp{5}.
23451 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
23452 Same as @code{max-clients} but for the admin interface.
23454 Defaults to @samp{5}.
23458 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
23459 Same as @code{max-queued-clients} but for the admin interface.
23461 Defaults to @samp{5}.
23465 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
23466 Same as @code{max-client-requests} but for the admin interface.
23468 Defaults to @samp{5}.
23472 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
23473 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
23475 Defaults to @samp{3}.
23479 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
23482 A filter allows to select a different logging level for a given category
23483 of logs The format for a filter is one of:
23494 where @code{name} is a string which is matched against the category
23495 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
23496 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
23497 be a substring of the full category name, in order to match multiple
23498 similar categories), the optional "+" prefix tells libvirt to log stack
23499 trace for each message matching name, and @code{x} is the minimal level
23500 where matching messages should be logged:
23517 Multiple filters can be defined in a single filters statement, they just
23518 need to be separated by spaces.
23520 Defaults to @samp{"3:remote 4:event"}.
23524 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
23527 An output is one of the places to save logging information. The format
23528 for an output can be:
23532 output goes to stderr
23534 @item x:syslog:name
23535 use syslog for the output and use the given name as the ident
23537 @item x:file:file_path
23538 output to a file, with the given filepath
23541 output to journald logging system
23545 In all case the x prefix is the minimal level, acting as a filter
23562 Multiple outputs can be defined, they just need to be separated by
23565 Defaults to @samp{"3:stderr"}.
23569 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
23570 Allows usage of the auditing subsystem to be altered
23574 0: disable all auditing
23577 1: enable auditing, only if enabled on host
23580 2: enable auditing, and exit if disabled on host.
23584 Defaults to @samp{1}.
23588 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
23589 Send audit messages via libvirt logging infrastructure.
23591 Defaults to @samp{#f}.
23595 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
23596 Host UUID. UUID must not have all digits be the same.
23598 Defaults to @samp{""}.
23602 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
23603 Source to read host UUID.
23607 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
23610 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
23614 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
23617 Defaults to @samp{"smbios"}.
23621 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
23622 A keepalive message is sent to a client after @code{keepalive_interval}
23623 seconds of inactivity to check if the client is still responding. If
23624 set to -1, libvirtd will never send keepalive requests; however clients
23625 can still send them and the daemon will send responses.
23627 Defaults to @samp{5}.
23631 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
23632 Maximum number of keepalive messages that are allowed to be sent to the
23633 client without getting any response before the connection is considered
23636 In other words, the connection is automatically closed approximately
23637 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
23638 the last message received from the client. When @code{keepalive-count}
23639 is set to 0, connections will be automatically closed after
23640 @code{keepalive-interval} seconds of inactivity without sending any
23641 keepalive messages.
23643 Defaults to @samp{5}.
23647 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
23648 Same as above but for admin interface.
23650 Defaults to @samp{5}.
23654 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
23655 Same as above but for admin interface.
23657 Defaults to @samp{5}.
23661 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
23662 Timeout for Open vSwitch calls.
23664 The @code{ovs-vsctl} utility is used for the configuration and its
23665 timeout option is set by default to 5 seconds to avoid potential
23666 infinite waits blocking libvirt.
23668 Defaults to @samp{5}.
23672 @c %end of autogenerated docs
23674 @subsubheading Virtlog daemon
23675 The virtlogd service is a server side daemon component of libvirt that is
23676 used to manage logs from virtual machine consoles.
23678 This daemon is not used directly by libvirt client applications, rather it
23679 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
23680 standalone daemon, the main @code{libvirtd} daemon can be restarted without
23681 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
23682 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
23684 @deffn {Scheme Variable} virtlog-service-type
23685 This is the type of the virtlog daemon.
23686 Its value must be a @code{virtlog-configuration}.
23689 (service virtlog-service-type
23690 (virtlog-configuration
23691 (max-clients 1000)))
23695 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
23696 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
23698 Defaults to @samp{3}.
23702 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
23705 A filter allows to select a different logging level for a given category
23706 of logs The format for a filter is one of:
23717 where @code{name} is a string which is matched against the category
23718 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
23719 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
23720 be a substring of the full category name, in order to match multiple
23721 similar categories), the optional "+" prefix tells libvirt to log stack
23722 trace for each message matching name, and @code{x} is the minimal level
23723 where matching messages should be logged:
23740 Multiple filters can be defined in a single filters statement, they just
23741 need to be separated by spaces.
23743 Defaults to @samp{"3:remote 4:event"}.
23747 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
23750 An output is one of the places to save logging information The format
23751 for an output can be:
23755 output goes to stderr
23757 @item x:syslog:name
23758 use syslog for the output and use the given name as the ident
23760 @item x:file:file_path
23761 output to a file, with the given filepath
23764 output to journald logging system
23768 In all case the x prefix is the minimal level, acting as a filter
23785 Multiple outputs can be defined, they just need to be separated by
23788 Defaults to @samp{"3:stderr"}.
23792 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
23793 Maximum number of concurrent client connections to allow over all
23796 Defaults to @samp{1024}.
23800 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
23801 Maximum file size before rolling over.
23803 Defaults to @samp{2MB}
23807 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
23808 Maximum number of backup files to keep.
23810 Defaults to @samp{3}
23814 @subsubheading Transparent Emulation with QEMU
23817 @cindex @code{binfmt_misc}
23818 @code{qemu-binfmt-service-type} provides support for transparent
23819 emulation of program binaries built for different architectures---e.g.,
23820 it allows you to transparently execute an ARMv7 program on an x86_64
23821 machine. It achieves this by combining the @uref{https://www.qemu.org,
23822 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
23824 @defvr {Scheme Variable} qemu-binfmt-service-type
23825 This is the type of the QEMU/binfmt service for transparent emulation.
23826 Its value must be a @code{qemu-binfmt-configuration} object, which
23827 specifies the QEMU package to use as well as the architecture we want to
23831 (service qemu-binfmt-service-type
23832 (qemu-binfmt-configuration
23833 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
23836 In this example, we enable transparent emulation for the ARM and aarch64
23837 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
23838 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
23839 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
23842 @deftp {Data Type} qemu-binfmt-configuration
23843 This is the configuration for the @code{qemu-binfmt} service.
23846 @item @code{platforms} (default: @code{'()})
23847 The list of emulated QEMU platforms. Each item must be a @dfn{platform
23848 object} as returned by @code{lookup-qemu-platforms} (see below).
23850 @item @code{guix-support?} (default: @code{#f})
23851 When it is true, QEMU and all its dependencies are added to the build
23852 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
23853 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
23854 handlers to be used within the build environment, which in turn means
23855 that you can transparently build programs for another architecture.
23857 For example, let's suppose you're on an x86_64 machine and you have this
23861 (service qemu-binfmt-service-type
23862 (qemu-binfmt-configuration
23863 (platforms (lookup-qemu-platforms "arm"))
23864 (guix-support? #t)))
23870 guix build -s armhf-linux inkscape
23874 and it will build Inkscape for ARMv7 @emph{as if it were a native
23875 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
23876 if you'd like to test a package build for an architecture you don't have
23879 @item @code{qemu} (default: @code{qemu})
23880 The QEMU package to use.
23884 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
23885 Return the list of QEMU platform objects corresponding to
23886 @var{platforms}@dots{}. @var{platforms} must be a list of strings
23887 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
23888 @code{"mips64el"}, and so on.
23891 @deffn {Scheme Procedure} qemu-platform? @var{obj}
23892 Return true if @var{obj} is a platform object.
23895 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
23896 Return the name of @var{platform}---a string such as @code{"arm"}.
23899 @node Version Control Services
23900 @subsection Version Control Services
23902 The @code{(gnu services version-control)} module provides a service to
23903 allow remote access to local Git repositories. There are three options:
23904 the @code{git-daemon-service}, which provides access to repositories via
23905 the @code{git://} unsecured TCP-based protocol, extending the
23906 @code{nginx} web server to proxy some requests to
23907 @code{git-http-backend}, or providing a web interface with
23908 @code{cgit-service-type}.
23910 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
23912 Return a service that runs @command{git daemon}, a simple TCP server to
23913 expose repositories over the Git protocol for anonymous access.
23915 The optional @var{config} argument should be a
23916 @code{<git-daemon-configuration>} object, by default it allows read-only
23917 access to exported@footnote{By creating the magic file
23918 "git-daemon-export-ok" in the repository directory.} repositories under
23923 @deftp {Data Type} git-daemon-configuration
23924 Data type representing the configuration for @code{git-daemon-service}.
23927 @item @code{package} (default: @var{git})
23928 Package object of the Git distributed version control system.
23930 @item @code{export-all?} (default: @var{#f})
23931 Whether to allow access for all Git repositories, even if they do not
23932 have the @file{git-daemon-export-ok} file.
23934 @item @code{base-path} (default: @file{/srv/git})
23935 Whether to remap all the path requests as relative to the given path.
23936 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
23937 then if you later try to pull @code{git://example.com/hello.git}, git
23938 daemon will interpret the path as @code{/srv/git/hello.git}.
23940 @item @code{user-path} (default: @var{#f})
23941 Whether to allow @code{~user} notation to be used in requests. When
23942 specified with empty string, requests to @code{git://host/~alice/foo} is
23943 taken as a request to access @code{foo} repository in the home directory
23944 of user @code{alice}. If @var{(user-path "path")} is specified, the
23945 same request is taken as a request to access @code{path/foo} repository
23946 in the home directory of user @code{alice}.
23948 @item @code{listen} (default: @var{'()})
23949 Whether to listen on specific IP addresses or hostnames, defaults to
23952 @item @code{port} (default: @var{#f})
23953 Whether to listen on an alternative port, which defaults to 9418.
23955 @item @code{whitelist} (default: @var{'()})
23956 If not empty, only allow access to this list of directories.
23958 @item @code{extra-options} (default: @var{'()})
23959 Extra options will be passed to @code{git daemon}, please run
23960 @command{man git-daemon} for more information.
23965 The @code{git://} protocol lacks authentication. When you pull from a
23966 repository fetched via @code{git://}, you don't know whether the data you
23967 receive was modified or is even coming from the specified host, and your
23968 connection is subject to eavesdropping. It's better to use an authenticated
23969 and encrypted transport, such as @code{https}. Although Git allows you
23970 to serve repositories using unsophisticated file-based web servers,
23971 there is a faster protocol implemented by the @code{git-http-backend}
23972 program. This program is the back-end of a proper Git web service. It
23973 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
23974 on running the necessary @code{fcgiwrap} daemon.
23976 Guix has a separate configuration data type for serving Git repositories
23979 @deftp {Data Type} git-http-configuration
23980 Data type representing the configuration for @code{git-http-service}.
23983 @item @code{package} (default: @var{git})
23984 Package object of the Git distributed version control system.
23986 @item @code{git-root} (default: @file{/srv/git})
23987 Directory containing the Git repositories to expose to the world.
23989 @item @code{export-all?} (default: @var{#f})
23990 Whether to expose access for all Git repositories in @var{git-root},
23991 even if they do not have the @file{git-daemon-export-ok} file.
23993 @item @code{uri-path} (default: @file{/git/})
23994 Path prefix for Git access. With the default @code{/git/} prefix, this
23995 will map @code{http://@var{server}/git/@var{repo}.git} to
23996 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
23997 with this prefix are not passed on to this Git instance.
23999 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
24000 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
24005 There is no @code{git-http-service-type}, currently; instead you can
24006 create an @code{nginx-location-configuration} from a
24007 @code{git-http-configuration} and then add that location to a web
24010 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
24011 [config=(git-http-configuration)]
24012 Compute an @code{nginx-location-configuration} that corresponds to the
24013 given Git http configuration. An example nginx service definition to
24014 serve the default @file{/srv/git} over HTTPS might be:
24017 (service nginx-service-type
24018 (nginx-configuration
24021 (nginx-server-configuration
24022 (listen '("443 ssl"))
24023 (server-name "git.my-host.org")
24025 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
24026 (ssl-certificate-key
24027 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
24030 (git-http-nginx-location-configuration
24031 (git-http-configuration (uri-path "/"))))))))))
24034 This example assumes that you are using Let's Encrypt to get your TLS
24035 certificate. @xref{Certificate Services}. The default @code{certbot}
24036 service will redirect all HTTP traffic on @code{git.my-host.org} to
24037 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
24038 system services. @xref{Web Services}.
24041 @subsubheading Cgit Service
24043 @cindex Cgit service
24044 @cindex Git, web interface
24045 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
24046 repositories written in C.
24048 The following example will configure the service with default values.
24049 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
24052 (service cgit-service-type)
24055 The @code{file-object} type designates either a file-like object
24056 (@pxref{G-Expressions, file-like objects}) or a string.
24058 @c %start of fragment
24060 Available @code{cgit-configuration} fields are:
24062 @deftypevr {@code{cgit-configuration} parameter} package package
24067 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
24068 NGINX configuration.
24072 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
24073 Specifies a command which will be invoked to format the content of about
24074 pages (both top-level and for each repository).
24076 Defaults to @samp{""}.
24080 @deftypevr {@code{cgit-configuration} parameter} string agefile
24081 Specifies a path, relative to each repository path, which can be used to
24082 specify the date and time of the youngest commit in the repository.
24084 Defaults to @samp{""}.
24088 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
24089 Specifies a command that will be invoked for authenticating repository
24092 Defaults to @samp{""}.
24096 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
24097 Flag which, when set to @samp{age}, enables date ordering in the branch
24098 ref list, and when set @samp{name} enables ordering by branch name.
24100 Defaults to @samp{"name"}.
24104 @deftypevr {@code{cgit-configuration} parameter} string cache-root
24105 Path used to store the cgit cache entries.
24107 Defaults to @samp{"/var/cache/cgit"}.
24111 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
24112 Number which specifies the time-to-live, in minutes, for the cached
24113 version of repository pages accessed with a fixed SHA1.
24115 Defaults to @samp{-1}.
24119 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
24120 Number which specifies the time-to-live, in minutes, for the cached
24121 version of repository pages accessed without a fixed SHA1.
24123 Defaults to @samp{5}.
24127 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
24128 Number which specifies the time-to-live, in minutes, for the cached
24129 version of the repository summary page.
24131 Defaults to @samp{5}.
24135 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
24136 Number which specifies the time-to-live, in minutes, for the cached
24137 version of the repository index page.
24139 Defaults to @samp{5}.
24143 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
24144 Number which specifies the time-to-live, in minutes, for the result of
24145 scanning a path for Git repositories.
24147 Defaults to @samp{15}.
24151 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
24152 Number which specifies the time-to-live, in minutes, for the cached
24153 version of the repository about page.
24155 Defaults to @samp{15}.
24159 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
24160 Number which specifies the time-to-live, in minutes, for the cached
24161 version of snapshots.
24163 Defaults to @samp{5}.
24167 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
24168 The maximum number of entries in the cgit cache. When set to @samp{0},
24169 caching is disabled.
24171 Defaults to @samp{0}.
24175 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
24176 Sort items in the repo list case sensitively.
24178 Defaults to @samp{#t}.
24182 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
24183 List of common prefixes which, when combined with a repository URL,
24184 generates valid clone URLs for the repository.
24186 Defaults to @samp{()}.
24190 @deftypevr {@code{cgit-configuration} parameter} list clone-url
24191 List of @code{clone-url} templates.
24193 Defaults to @samp{()}.
24197 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
24198 Command which will be invoked to format commit messages.
24200 Defaults to @samp{""}.
24204 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
24205 Flag which, when set to @samp{date}, enables strict date ordering in the
24206 commit log, and when set to @samp{topo} enables strict topological
24209 Defaults to @samp{"git log"}.
24213 @deftypevr {@code{cgit-configuration} parameter} file-object css
24214 URL which specifies the css document to include in all cgit pages.
24216 Defaults to @samp{"/share/cgit/cgit.css"}.
24220 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
24221 Specifies a command which will be invoked to format names and email
24222 address of committers, authors, and taggers, as represented in various
24223 places throughout the cgit interface.
24225 Defaults to @samp{""}.
24229 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
24230 Flag which, when set to @samp{#t}, will make cgit generate a HTML
24231 fragment suitable for embedding in other HTML pages.
24233 Defaults to @samp{#f}.
24237 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
24238 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
24239 commit history graph to the left of the commit messages in the
24240 repository log page.
24242 Defaults to @samp{#f}.
24246 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
24247 Flag which, when set to @samp{#t}, allows all filter settings to be
24248 overridden in repository-specific cgitrc files.
24250 Defaults to @samp{#f}.
24254 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
24255 Flag which, when set to @samp{#t}, allows users to follow a file in the
24258 Defaults to @samp{#f}.
24262 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
24263 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
24266 Defaults to @samp{#t}.
24270 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
24271 Flag which, when set to @samp{#t}, will make cgit generate extra links
24272 "summary", "commit", "tree" for each repo in the repository index.
24274 Defaults to @samp{#f}.
24278 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
24279 Flag which, when set to @samp{#t}, will make cgit display the owner of
24280 each repo in the repository index.
24282 Defaults to @samp{#t}.
24286 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
24287 Flag which, when set to @samp{#t}, will make cgit print the number of
24288 modified files for each commit on the repository log page.
24290 Defaults to @samp{#f}.
24294 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
24295 Flag which, when set to @samp{#t}, will make cgit print the number of
24296 added and removed lines for each commit on the repository log page.
24298 Defaults to @samp{#f}.
24302 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
24303 Flag which, when set to @code{#t}, will make cgit display remote
24304 branches in the summary and refs views.
24306 Defaults to @samp{#f}.
24310 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
24311 Flag which, when set to @code{1}, will make cgit use the subject of the
24312 parent commit as link text when generating links to parent commits in
24315 Defaults to @samp{#f}.
24319 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
24320 Flag which, when set to @samp{#t}, will make cgit use the subject of the
24321 parent commit as link text when generating links to parent commits in
24324 Defaults to @samp{#f}.
24328 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
24329 Flag which, when set to @samp{#t}, will make cgit generate linenumber
24330 links for plaintext blobs printed in the tree view.
24332 Defaults to @samp{#t}.
24336 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
24337 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
24338 set any repo specific settings.
24340 Defaults to @samp{#f}.
24344 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
24345 URL used as link to a shortcut icon for cgit.
24347 Defaults to @samp{"/favicon.ico"}.
24351 @deftypevr {@code{cgit-configuration} parameter} string footer
24352 The content of the file specified with this option will be included
24353 verbatim at the bottom of all pages (i.e.@: it replaces the standard
24354 "generated by..."@: message).
24356 Defaults to @samp{""}.
24360 @deftypevr {@code{cgit-configuration} parameter} string head-include
24361 The content of the file specified with this option will be included
24362 verbatim in the HTML HEAD section on all pages.
24364 Defaults to @samp{""}.
24368 @deftypevr {@code{cgit-configuration} parameter} string header
24369 The content of the file specified with this option will be included
24370 verbatim at the top of all pages.
24372 Defaults to @samp{""}.
24376 @deftypevr {@code{cgit-configuration} parameter} file-object include
24377 Name of a configfile to include before the rest of the current config-
24380 Defaults to @samp{""}.
24384 @deftypevr {@code{cgit-configuration} parameter} string index-header
24385 The content of the file specified with this option will be included
24386 verbatim above the repository index.
24388 Defaults to @samp{""}.
24392 @deftypevr {@code{cgit-configuration} parameter} string index-info
24393 The content of the file specified with this option will be included
24394 verbatim below the heading on the repository index page.
24396 Defaults to @samp{""}.
24400 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
24401 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
24402 in the servers timezone.
24404 Defaults to @samp{#f}.
24408 @deftypevr {@code{cgit-configuration} parameter} file-object logo
24409 URL which specifies the source of an image which will be used as a logo
24412 Defaults to @samp{"/share/cgit/cgit.png"}.
24416 @deftypevr {@code{cgit-configuration} parameter} string logo-link
24417 URL loaded when clicking on the cgit logo image.
24419 Defaults to @samp{""}.
24423 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
24424 Command which will be invoked to format the Owner column of the main
24427 Defaults to @samp{""}.
24431 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
24432 Number of items to display in atom feeds view.
24434 Defaults to @samp{10}.
24438 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
24439 Number of entries to list per page in "log" view.
24441 Defaults to @samp{50}.
24445 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
24446 Number of commit message characters to display in "log" view.
24448 Defaults to @samp{80}.
24452 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
24453 Specifies the number of entries to list per page on the repository index
24456 Defaults to @samp{50}.
24460 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
24461 Specifies the maximum number of repo description characters to display
24462 on the repository index page.
24464 Defaults to @samp{80}.
24468 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
24469 Specifies the maximum size of a blob to display HTML for in KBytes.
24471 Defaults to @samp{0}.
24475 @deftypevr {@code{cgit-configuration} parameter} string max-stats
24476 Maximum statistics period. Valid values are @samp{week},@samp{month},
24477 @samp{quarter} and @samp{year}.
24479 Defaults to @samp{""}.
24483 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
24484 Mimetype for the specified filename extension.
24486 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
24487 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
24488 "image/png") (svg "image/svg+xml"))}.
24492 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
24493 Specifies the file to use for automatic mimetype lookup.
24495 Defaults to @samp{""}.
24499 @deftypevr {@code{cgit-configuration} parameter} string module-link
24500 Text which will be used as the formatstring for a hyperlink when a
24501 submodule is printed in a directory listing.
24503 Defaults to @samp{""}.
24507 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
24508 If set to the value @samp{#t} caching will be disabled.
24510 Defaults to @samp{#f}.
24514 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
24515 If set to @samp{#t} showing full author email addresses will be
24518 Defaults to @samp{#f}.
24522 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
24523 Flag which, when set to @samp{#t}, will make cgit omit the standard
24524 header on all pages.
24526 Defaults to @samp{#f}.
24530 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
24531 A list of subdirectories inside of @code{repository-directory}, relative
24532 to it, that should loaded as Git repositories. An empty list means that
24533 all subdirectories will be loaded.
24535 Defaults to @samp{()}.
24539 @deftypevr {@code{cgit-configuration} parameter} file-object readme
24540 Text which will be used as default value for @code{cgit-repo-readme}.
24542 Defaults to @samp{""}.
24546 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
24547 If set to @code{#t} and @code{repository-directory} is enabled, if any
24548 repositories are found with a suffix of @code{.git}, this suffix will be
24549 removed for the URL and name.
24551 Defaults to @samp{#f}.
24555 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
24556 Maximum number of files to consider when detecting renames.
24558 Defaults to @samp{-1}.
24562 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
24563 The way in which repositories in each section are sorted.
24565 Defaults to @samp{""}.
24569 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
24570 Text used as content for the @code{robots} meta-tag.
24572 Defaults to @samp{("noindex" "nofollow")}.
24576 @deftypevr {@code{cgit-configuration} parameter} string root-desc
24577 Text printed below the heading on the repository index page.
24579 Defaults to @samp{"a fast webinterface for the git dscm"}.
24583 @deftypevr {@code{cgit-configuration} parameter} string root-readme
24584 The content of the file specified with this option will be included
24585 verbatim below thef "about" link on the repository index page.
24587 Defaults to @samp{""}.
24591 @deftypevr {@code{cgit-configuration} parameter} string root-title
24592 Text printed as heading on the repository index page.
24594 Defaults to @samp{""}.
24598 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
24599 If set to @samp{#t} and repository-directory is enabled,
24600 repository-directory will recurse into directories whose name starts
24601 with a period. Otherwise, repository-directory will stay away from such
24602 directories, considered as "hidden". Note that this does not apply to
24603 the ".git" directory in non-bare repos.
24605 Defaults to @samp{#f}.
24609 @deftypevr {@code{cgit-configuration} parameter} list snapshots
24610 Text which specifies the default set of snapshot formats that cgit
24611 generates links for.
24613 Defaults to @samp{()}.
24617 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
24618 Name of the directory to scan for repositories (represents
24621 Defaults to @samp{"/srv/git"}.
24625 @deftypevr {@code{cgit-configuration} parameter} string section
24626 The name of the current repository section - all repositories defined
24627 after this option will inherit the current section name.
24629 Defaults to @samp{""}.
24633 @deftypevr {@code{cgit-configuration} parameter} string section-sort
24634 Flag which, when set to @samp{1}, will sort the sections on the
24635 repository listing by name.
24637 Defaults to @samp{""}.
24641 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
24642 A number which, if defined prior to repository-directory, specifies how
24643 many path elements from each repo path to use as a default section name.
24645 Defaults to @samp{0}.
24649 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
24650 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
24653 Defaults to @samp{#f}.
24657 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
24658 Specifies a command which will be invoked to format plaintext blobs in
24661 Defaults to @samp{""}.
24665 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
24666 Specifies the number of branches to display in the repository "summary"
24669 Defaults to @samp{10}.
24673 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
24674 Specifies the number of log entries to display in the repository
24677 Defaults to @samp{10}.
24681 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
24682 Specifies the number of tags to display in the repository "summary"
24685 Defaults to @samp{10}.
24689 @deftypevr {@code{cgit-configuration} parameter} string strict-export
24690 Filename which, if specified, needs to be present within the repository
24691 for cgit to allow access to that repository.
24693 Defaults to @samp{""}.
24697 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
24698 URL which, if specified, will be used as root for all cgit links.
24700 Defaults to @samp{"/"}.
24704 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
24705 A list of @dfn{cgit-repo} records to use with config.
24707 Defaults to @samp{()}.
24709 Available @code{repository-cgit-configuration} fields are:
24711 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
24712 A mask of snapshot formats for this repo that cgit generates links for,
24713 restricted by the global @code{snapshots} setting.
24715 Defaults to @samp{()}.
24719 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
24720 Override the default @code{source-filter}.
24722 Defaults to @samp{""}.
24726 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
24727 The relative URL used to access the repository.
24729 Defaults to @samp{""}.
24733 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
24734 Override the default @code{about-filter}.
24736 Defaults to @samp{""}.
24740 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
24741 Flag which, when set to @samp{age}, enables date ordering in the branch
24742 ref list, and when set to @samp{name} enables ordering by branch name.
24744 Defaults to @samp{""}.
24748 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
24749 A list of URLs which can be used to clone repo.
24751 Defaults to @samp{()}.
24755 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
24756 Override the default @code{commit-filter}.
24758 Defaults to @samp{""}.
24762 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
24763 Flag which, when set to @samp{date}, enables strict date ordering in the
24764 commit log, and when set to @samp{topo} enables strict topological
24767 Defaults to @samp{""}.
24771 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
24772 The name of the default branch for this repository. If no such branch
24773 exists in the repository, the first branch name (when sorted) is used as
24774 default instead. By default branch pointed to by HEAD, or "master" if
24775 there is no suitable HEAD.
24777 Defaults to @samp{""}.
24781 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
24782 The value to show as repository description.
24784 Defaults to @samp{""}.
24788 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
24789 The value to show as repository homepage.
24791 Defaults to @samp{""}.
24795 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
24796 Override the default @code{email-filter}.
24798 Defaults to @samp{""}.
24802 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
24803 A flag which can be used to disable the global setting
24804 @code{enable-commit-graph?}.
24806 Defaults to @samp{disabled}.
24810 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
24811 A flag which can be used to disable the global setting
24812 @code{enable-log-filecount?}.
24814 Defaults to @samp{disabled}.
24818 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
24819 A flag which can be used to disable the global setting
24820 @code{enable-log-linecount?}.
24822 Defaults to @samp{disabled}.
24826 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
24827 Flag which, when set to @code{#t}, will make cgit display remote
24828 branches in the summary and refs views.
24830 Defaults to @samp{disabled}.
24834 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
24835 A flag which can be used to override the global setting
24836 @code{enable-subject-links?}.
24838 Defaults to @samp{disabled}.
24842 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
24843 A flag which can be used to override the global setting
24844 @code{enable-html-serving?}.
24846 Defaults to @samp{disabled}.
24850 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
24851 Flag which, when set to @code{#t}, hides the repository from the
24854 Defaults to @samp{#f}.
24858 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
24859 Flag which, when set to @samp{#t}, ignores the repository.
24861 Defaults to @samp{#f}.
24865 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
24866 URL which specifies the source of an image which will be used as a logo
24867 on this repo’s pages.
24869 Defaults to @samp{""}.
24873 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
24874 URL loaded when clicking on the cgit logo image.
24876 Defaults to @samp{""}.
24880 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
24881 Override the default @code{owner-filter}.
24883 Defaults to @samp{""}.
24887 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
24888 Text which will be used as the formatstring for a hyperlink when a
24889 submodule is printed in a directory listing. The arguments for the
24890 formatstring are the path and SHA1 of the submodule commit.
24892 Defaults to @samp{""}.
24896 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
24897 Text which will be used as the formatstring for a hyperlink when a
24898 submodule with the specified subdirectory path is printed in a directory
24901 Defaults to @samp{()}.
24905 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
24906 Override the default maximum statistics period.
24908 Defaults to @samp{""}.
24912 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
24913 The value to show as repository name.
24915 Defaults to @samp{""}.
24919 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
24920 A value used to identify the owner of the repository.
24922 Defaults to @samp{""}.
24926 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
24927 An absolute path to the repository directory.
24929 Defaults to @samp{""}.
24933 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
24934 A path (relative to repo) which specifies a file to include verbatim as
24935 the "About" page for this repo.
24937 Defaults to @samp{""}.
24941 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
24942 The name of the current repository section - all repositories defined
24943 after this option will inherit the current section name.
24945 Defaults to @samp{""}.
24949 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
24950 Extra options will be appended to cgitrc file.
24952 Defaults to @samp{()}.
24958 @deftypevr {@code{cgit-configuration} parameter} list extra-options
24959 Extra options will be appended to cgitrc file.
24961 Defaults to @samp{()}.
24966 @c %end of fragment
24968 However, it could be that you just want to get a @code{cgitrc} up and
24969 running. In that case, you can pass an @code{opaque-cgit-configuration}
24970 as a record to @code{cgit-service-type}. As its name indicates, an
24971 opaque configuration does not have easy reflective capabilities.
24973 Available @code{opaque-cgit-configuration} fields are:
24975 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
24979 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
24980 The contents of the @code{cgitrc}, as a string.
24983 For example, if your @code{cgitrc} is just the empty string, you
24984 could instantiate a cgit service like this:
24987 (service cgit-service-type
24988 (opaque-cgit-configuration
24992 @subsubheading Gitolite Service
24994 @cindex Gitolite service
24995 @cindex Git, hosting
24996 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
24997 repositories on a central server.
24999 Gitolite can handle multiple repositories and users, and supports flexible
25000 configuration of the permissions for the users on the repositories.
25002 The following example will configure Gitolite using the default @code{git}
25003 user, and the provided SSH public key.
25006 (service gitolite-service-type
25007 (gitolite-configuration
25008 (admin-pubkey (plain-file
25010 "ssh-rsa AAAA... guix@@example.com"))))
25013 Gitolite is configured through a special admin repository which you can clone,
25014 for example, if you setup Gitolite on @code{example.com}, you would run the
25015 following command to clone the admin repository.
25018 git clone git@@example.com:gitolite-admin
25021 When the Gitolite service is activated, the provided @code{admin-pubkey} will
25022 be inserted in to the @file{keydir} directory in the gitolite-admin
25023 repository. If this results in a change in the repository, it will be
25024 committed using the message ``gitolite setup by GNU Guix''.
25026 @deftp {Data Type} gitolite-configuration
25027 Data type representing the configuration for @code{gitolite-service-type}.
25030 @item @code{package} (default: @var{gitolite})
25031 Gitolite package to use.
25033 @item @code{user} (default: @var{git})
25034 User to use for Gitolite. This will be user that you use when accessing
25037 @item @code{group} (default: @var{git})
25038 Group to use for Gitolite.
25040 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
25041 Directory in which to store the Gitolite configuration and repositories.
25043 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
25044 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
25045 representing the configuration for Gitolite.
25047 @item @code{admin-pubkey} (default: @var{#f})
25048 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
25049 setup Gitolite. This will be inserted in to the @file{keydir} directory
25050 within the gitolite-admin repository.
25052 To specify the SSH key as a string, use the @code{plain-file} function.
25055 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
25061 @deftp {Data Type} gitolite-rc-file
25062 Data type representing the Gitolite RC file.
25065 @item @code{umask} (default: @code{#o0077})
25066 This controls the permissions Gitolite sets on the repositories and their
25069 A value like @code{#o0027} will give read access to the group used by Gitolite
25070 (by default: @code{git}). This is necessary when using Gitolite with software
25071 like cgit or gitweb.
25073 @item @code{git-config-keys} (default: @code{""})
25074 Gitolite allows you to set git config values using the "config" keyword. This
25075 setting allows control over the config keys to accept.
25077 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
25078 Set the role names allowed to be used by users running the perms command.
25080 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
25081 This setting controls the commands and features to enable within Gitolite.
25087 @node Game Services
25088 @subsection Game Services
25090 @subsubheading The Battle for Wesnoth Service
25092 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
25093 based tactical strategy game, with several single player campaigns, and
25094 multiplayer games (both networked and local).
25096 @defvar {Scheme Variable} wesnothd-service-type
25097 Service type for the wesnothd service. Its value must be a
25098 @code{wesnothd-configuration} object. To run wesnothd in the default
25099 configuration, instantiate it as:
25102 (service wesnothd-service-type)
25106 @deftp {Data Type} wesnothd-configuration
25107 Data type representing the configuration of @command{wesnothd}.
25110 @item @code{package} (default: @code{wesnoth-server})
25111 The wesnoth server package to use.
25113 @item @code{port} (default: @code{15000})
25114 The port to bind the server to.
25119 @node PAM Mount Service
25120 @subsection PAM Mount Service
25123 The @code{(gnu services pam-mount)} module provides a service allowing
25124 users to mount volumes when they log in. It should be able to mount any
25125 volume format supported by the system.
25127 @defvar {Scheme Variable} pam-mount-service-type
25128 Service type for PAM Mount support.
25131 @deftp {Data Type} pam-mount-configuration
25132 Data type representing the configuration of PAM Mount.
25134 It takes the following parameters:
25138 The configuration rules that will be used to generate
25139 @file{/etc/security/pam_mount.conf.xml}.
25141 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
25142 Guile Reference Manual}), and the the default ones don't mount anything
25143 for anyone at login:
25146 `((debug (@@ (enable "0")))
25147 (mntoptions (@@ (allow ,(string-join
25148 '("nosuid" "nodev" "loop"
25149 "encryption" "fsck" "nonempty"
25150 "allow_root" "allow_other")
25152 (mntoptions (@@ (require "nosuid,nodev")))
25153 (logout (@@ (wait "0")
25157 (mkmountpoint (@@ (enable "1")
25161 Some @code{volume} elements must be added to automatically mount volumes
25162 at login. Here's an example allowing the user @code{alice} to mount her
25163 encrypted @code{HOME} directory and allowing the user @code{bob} to mount
25164 the partition where he stores his data:
25167 (define pam-mount-rules
25168 `((debug (@@ (enable "0")))
25169 (volume (@@ (user "alice")
25172 (mountpoint "/home/alice")))
25173 (volume (@@ (user "bob")
25176 (mountpoint "/home/bob/data")
25177 (options "defaults,autodefrag,compress")))
25178 (mntoptions (@@ (allow ,(string-join
25179 '("nosuid" "nodev" "loop"
25180 "encryption" "fsck" "nonempty"
25181 "allow_root" "allow_other")
25183 (mntoptions (@@ (require "nosuid,nodev")))
25184 (logout (@@ (wait "0")
25188 (mkmountpoint (@@ (enable "1")
25189 (remove "true")))))
25191 (service pam-mount-service-type
25192 (pam-mount-configuration
25193 (rules pam-mount-rules)))
25196 The complete list of possible options can be found in the man page for
25197 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
25202 @node Guix Services
25203 @subsection Guix Services
25205 @subsubheading Guix Data Service
25206 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
25207 and provides data about GNU Guix. This includes information about
25208 packages, derivations and lint warnings.
25210 The data is stored in a PostgreSQL database, and available through a web
25213 @defvar {Scheme Variable} guix-data-service-type
25214 Service type for the Guix Data Service. Its value must be a
25215 @code{guix-data-service-configuration} object. The service optionally
25216 extends the getmail service, as the guix-commits mailing list is used to
25217 find out about changes in the Guix git repository.
25220 @deftp {Data Type} guix-data-service-configuration
25221 Data type representing the configuration of the Guix Data Service.
25224 @item @code{package} (default: @code{guix-data-service})
25225 The Guix Data Service package to use.
25227 @item @code{user} (default: @code{"guix-data-service"})
25228 The system user to run the service as.
25230 @item @code{group} (default: @code{"guix-data-service"})
25231 The system group to run the service as.
25233 @item @code{port} (default: @code{8765})
25234 The port to bind the web service to.
25236 @item @code{host} (default: @code{"127.0.0.1"})
25237 The host to bind the web service to.
25239 @item @code{getmail-idle-mailboxes} (default: @code{#f})
25240 If set, this is the list of mailboxes that the getmail service will be
25241 configured to listen to.
25243 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
25244 If set, this is the @code{getmail-retriever-configuration} object with
25245 which to configure getmail to fetch mail from the guix-commits mailing
25251 @node Linux Services
25252 @subsubheading Linux Services
25255 @cindex out of memory killer
25257 @cindex early out of memory daemon
25258 @subsection Early OOM Service
25260 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
25261 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
25262 space and provides a more responsive and configurable alternative to the
25263 in-kernel OOM killer. It is useful to prevent the system from becoming
25264 unresponsive when it runs out of memory.
25266 @deffn {Scheme Variable} earlyoom-service-type
25267 The service type for running @command{earlyoom}, the Early OOM daemon.
25268 Its value must be a @code{earlyoom-configuration} object, described
25269 below. The service can be instantiated in its default configuration
25273 (service earlyoom-service-type)
25277 @deftp {Data Type} earlyoom-configuration
25278 This is the configuration record for the @code{earlyoom-service-type}.
25281 @item @code{earlyoom} (default: @var{earlyoom})
25282 The Earlyoom package to use.
25284 @item @code{minimum-available-memory} (default: @code{10})
25285 The threshold for the minimum @emph{available} memory, in percentages.
25287 @item @code{minimum-free-swap} (default: @code{10})
25288 The threshold for the minimum free swap memory, in percentages.
25290 @item @code{prefer-regexp} (default: @code{#f})
25291 A regular expression (as a string) to match the names of the processes
25292 that should be preferably killed.
25294 @item @code{avoid-regexp} (default: @code{#f})
25295 A regular expression (as a string) to match the names of the processes
25296 that should @emph{not} be killed.
25298 @item @code{memory-report-interval} (default: @code{0})
25299 The interval in seconds at which a memory report is printed. It is
25300 disabled by default.
25302 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
25303 A boolean indicating whether the positive adjustments set in
25304 @file{/proc/*/oom_score_adj}.
25306 @item @code{show-debug-messages?} (default: @code{#f})
25307 A boolean indicating whether debug messages should be printed. The logs
25308 are saved at @file{/var/log/earlyoom.log}.
25310 @item @code{send-notification-command} (default: @code{#f})
25311 This can be used to provide a custom command used for sending
25317 @node Miscellaneous Services
25318 @subsection Miscellaneous Services
25320 @cindex fingerprint
25321 @subsubheading Fingerprint Service
25323 The @code{(gnu services authentication)} module provides a DBus service to
25324 read and identify fingerprints via a fingerprint sensor.
25326 @defvr {Scheme Variable} fprintd-service-type
25327 The service type for @command{fprintd}, which provides the fingerprint
25328 reading capability.
25331 (service fprintd-service-type)
25336 @subsubheading System Control Service
25338 The @code{(gnu services sysctl)} provides a service to configure kernel
25339 parameters at boot.
25341 @defvr {Scheme Variable} sysctl-service-type
25342 The service type for @command{sysctl}, which modifies kernel parameters
25343 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
25347 (service sysctl-service-type
25348 (sysctl-configuration
25349 (settings '(("net.ipv4.ip_forward" . "1")))))
25353 @deftp {Data Type} sysctl-configuration
25354 The data type representing the configuration of @command{sysctl}.
25357 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
25358 The @command{sysctl} executable to use.
25360 @item @code{settings} (default: @code{'()})
25361 An association list specifies kernel parameters and their values.
25366 @subsubheading PC/SC Smart Card Daemon Service
25368 The @code{(gnu services security-token)} module provides the following service
25369 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
25370 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
25371 manager that coordinates communications with smart card readers, smart cards
25372 and cryptographic tokens that are connected to the system.
25374 @defvr {Scheme Variable} pcscd-service-type
25375 Service type for the @command{pcscd} service. Its value must be a
25376 @code{pcscd-configuration} object. To run pcscd in the default
25377 configuration, instantiate it as:
25380 (service pcscd-service-type)
25384 @deftp {Data Type} pcscd-configuration
25385 The data type representing the configuration of @command{pcscd}.
25388 @item @code{pcsc-lite} (default: @code{pcsc-lite})
25389 The pcsc-lite package that provides pcscd.
25390 @item @code{usb-drivers} (default: @code{(list ccid)})
25391 List of packages that provide USB drivers to pcscd. Drivers are expected to be
25392 under @file{pcsc/drivers} in the store directory of the package.
25397 @subsubheading Lirc Service
25399 The @code{(gnu services lirc)} module provides the following service.
25401 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
25402 [#:device #f] [#:driver #f] [#:config-file #f] @
25403 [#:extra-options '()]
25404 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
25405 decodes infrared signals from remote controls.
25407 Optionally, @var{device}, @var{driver} and @var{config-file}
25408 (configuration file name) may be specified. See @command{lircd} manual
25411 Finally, @var{extra-options} is a list of additional command-line options
25412 passed to @command{lircd}.
25416 @subsubheading Spice Service
25418 The @code{(gnu services spice)} module provides the following service.
25420 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
25421 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
25422 that enables sharing the clipboard with a vm and setting the guest display
25423 resolution when the graphical console window resizes.
25426 @cindex inputattach
25427 @subsubheading inputattach Service
25429 @cindex tablet input, for Xorg
25430 @cindex touchscreen input, for Xorg
25431 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
25432 use input devices such as Wacom tablets, touchscreens, or joysticks with the
25433 Xorg display server.
25435 @deffn {Scheme Variable} inputattach-service-type
25436 Type of a service that runs @command{inputattach} on a device and
25437 dispatches events from it.
25440 @deftp {Data Type} inputattach-configuration
25442 @item @code{device-type} (default: @code{"wacom"})
25443 The type of device to connect to. Run @command{inputattach --help}, from the
25444 @code{inputattach} package, to see the list of supported device types.
25446 @item @code{device} (default: @code{"/dev/ttyS0"})
25447 The device file to connect to the device.
25449 @item @code{baud-rate} (default: @code{#f})
25450 Baud rate to use for the serial connection.
25451 Should be a number or @code{#f}.
25453 @item @code{log-file} (default: @code{#f})
25454 If true, this must be the name of a file to log messages to.
25458 @subsection Dictionary Services
25460 The @code{(gnu services dict)} module provides the following service:
25462 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
25463 Return a service that runs the @command{dicod} daemon, an implementation
25464 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
25466 The optional @var{config} argument specifies the configuration for
25467 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
25468 default it serves the GNU Collaborative International Dictonary of English.
25470 You can add @command{open localhost} to your @file{~/.dico} file to make
25471 @code{localhost} the default server for @command{dico} client
25472 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
25475 @deftp {Data Type} dicod-configuration
25476 Data type representing the configuration of dicod.
25479 @item @code{dico} (default: @var{dico})
25480 Package object of the GNU Dico dictionary server.
25482 @item @code{interfaces} (default: @var{'("localhost")})
25483 This is the list of IP addresses and ports and possibly socket file
25484 names to listen to (@pxref{Server Settings, @code{listen} directive,,
25485 dico, GNU Dico Manual}).
25487 @item @code{handlers} (default: @var{'()})
25488 List of @code{<dicod-handler>} objects denoting handlers (module instances).
25490 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
25491 List of @code{<dicod-database>} objects denoting dictionaries to be served.
25495 @deftp {Data Type} dicod-handler
25496 Data type representing a dictionary handler (module instance).
25500 Name of the handler (module instance).
25502 @item @code{module} (default: @var{#f})
25503 Name of the dicod module of the handler (instance). If it is @code{#f},
25504 the module has the same name as the handler.
25505 (@pxref{Modules,,, dico, GNU Dico Manual}).
25507 @item @code{options}
25508 List of strings or gexps representing the arguments for the module handler
25512 @deftp {Data Type} dicod-database
25513 Data type representing a dictionary database.
25517 Name of the database, will be used in DICT commands.
25519 @item @code{handler}
25520 Name of the dicod handler (module instance) used by this database
25521 (@pxref{Handlers,,, dico, GNU Dico Manual}).
25523 @item @code{complex?} (default: @var{#f})
25524 Whether the database configuration complex. The complex configuration
25525 will need a corresponding @code{<dicod-handler>} object, otherwise not.
25527 @item @code{options}
25528 List of strings or gexps representing the arguments for the database
25529 (@pxref{Databases,,, dico, GNU Dico Manual}).
25533 @defvr {Scheme Variable} %dicod-database:gcide
25534 A @code{<dicod-database>} object serving the GNU Collaborative International
25535 Dictionary of English using the @code{gcide} package.
25538 The following is an example @code{dicod-service} configuration.
25541 (dicod-service #:config
25542 (dicod-configuration
25543 (handlers (list (dicod-handler
25547 (list #~(string-append "dbdir=" #$wordnet))))))
25548 (databases (list (dicod-database
25551 (handler "wordnet")
25552 (options '("database=wn")))
25553 %dicod-database:gcide))))
25557 @subsubheading Docker Service
25559 The @code{(gnu services docker)} module provides the following services.
25561 @defvr {Scheme Variable} docker-service-type
25563 This is the type of the service that runs @url{https://www.docker.com,Docker},
25564 a daemon that can execute application bundles (sometimes referred to as
25565 ``containers'') in isolated environments.
25569 @deftp {Data Type} docker-configuration
25570 This is the data type representing the configuration of Docker and Containerd.
25574 @item @code{package} (default: @code{docker})
25575 The Docker package to use.
25577 @item @code{containerd} (default: @var{containerd})
25578 The Containerd package to use.
25584 @subsubheading Auditd Service
25586 The @code{(gnu services auditd)} module provides the following service.
25588 @defvr {Scheme Variable} auditd-service-type
25590 This is the type of the service that runs
25591 @url{https://people.redhat.com/sgrubb/audit/,auditd},
25592 a daemon that tracks security-relevant information on your system.
25594 Examples of things that can be tracked:
25604 Failed login attempts
25611 @command{auditctl} from the @code{audit} package can be used in order
25612 to add or remove events to be tracked (until the next reboot).
25613 In order to permanently track events, put the command line arguments
25614 of auditctl into @file{/etc/audit/audit.rules}.
25615 @command{aureport} from the @code{audit} package can be used in order
25616 to view a report of all recorded events.
25617 The audit daemon usually logs into the directory @file{/var/log/audit}.
25621 @deftp {Data Type} auditd-configuration
25622 This is the data type representing the configuration of auditd.
25626 @item @code{audit} (default: @code{audit})
25627 The audit package to use.
25632 @defvr {Scheme Variable} singularity-service-type
25633 This is the type of the service that allows you to run
25634 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
25635 create and run application bundles (aka. ``containers''). The value for this
25636 service is the Singularity package to use.
25638 The service does not install a daemon; instead, it installs helper programs as
25639 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
25640 @command{singularity run} and similar commands.
25644 @subsubheading Nix service
25646 The @code{(gnu services nix)} module provides the following service.
25648 @defvr {Scheme Variable} nix-service-type
25650 This is the type of the service that runs build daemon of the
25651 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
25655 (use-modules (gnu))
25656 (use-service-modules nix)
25657 (use-package-modules package-management)
25661 (packages (append (list nix)
25664 (services (append (list (service nix-service-type))
25668 After @command{guix system reconfigure} configure Nix for your user:
25671 @item Add a Nix channel and update it. See
25672 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
25674 @item Create a symlink to your profile and activate Nix profile:
25678 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
25679 $ source /run/current-system/profile/etc/profile.d/nix.sh
25684 @node Setuid Programs
25685 @section Setuid Programs
25687 @cindex setuid programs
25688 Some programs need to run with ``root'' privileges, even when they are
25689 launched by unprivileged users. A notorious example is the
25690 @command{passwd} program, which users can run to change their
25691 password, and which needs to access the @file{/etc/passwd} and
25692 @file{/etc/shadow} files---something normally restricted to root, for
25693 obvious security reasons. To address that, these executables are
25694 @dfn{setuid-root}, meaning that they always run with root privileges
25695 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
25696 for more info about the setuid mechanism.)
25698 The store itself @emph{cannot} contain setuid programs: that would be a
25699 security issue since any user on the system can write derivations that
25700 populate the store (@pxref{The Store}). Thus, a different mechanism is
25701 used: instead of changing the setuid bit directly on files that are in
25702 the store, we let the system administrator @emph{declare} which programs
25703 should be setuid root.
25705 The @code{setuid-programs} field of an @code{operating-system}
25706 declaration contains a list of G-expressions denoting the names of
25707 programs to be setuid-root (@pxref{Using the Configuration System}).
25708 For instance, the @command{passwd} program, which is part of the Shadow
25709 package, can be designated by this G-expression (@pxref{G-Expressions}):
25712 #~(string-append #$shadow "/bin/passwd")
25715 A default set of setuid programs is defined by the
25716 @code{%setuid-programs} variable of the @code{(gnu system)} module.
25718 @defvr {Scheme Variable} %setuid-programs
25719 A list of G-expressions denoting common programs that are setuid-root.
25721 The list includes commands such as @command{passwd}, @command{ping},
25722 @command{su}, and @command{sudo}.
25725 Under the hood, the actual setuid programs are created in the
25726 @file{/run/setuid-programs} directory at system activation time. The
25727 files in this directory refer to the ``real'' binaries, which are in the
25730 @node X.509 Certificates
25731 @section X.509 Certificates
25733 @cindex HTTPS, certificates
25734 @cindex X.509 certificates
25736 Web servers available over HTTPS (that is, HTTP over the transport-layer
25737 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
25738 that the client can then use to @emph{authenticate} the server. To do
25739 that, clients verify that the server's certificate is signed by a
25740 so-called @dfn{certificate authority} (CA). But to verify the CA's
25741 signature, clients must have first acquired the CA's certificate.
25743 Web browsers such as GNU@tie{}IceCat include their own set of CA
25744 certificates, such that they are able to verify CA signatures
25747 However, most other programs that can talk HTTPS---@command{wget},
25748 @command{git}, @command{w3m}, etc.---need to be told where CA
25749 certificates can be found.
25751 @cindex @code{nss-certs}
25752 In Guix, this is done by adding a package that provides certificates
25753 to the @code{packages} field of the @code{operating-system} declaration
25754 (@pxref{operating-system Reference}). Guix includes one such package,
25755 @code{nss-certs}, which is a set of CA certificates provided as part of
25756 Mozilla's Network Security Services.
25758 Note that it is @emph{not} part of @code{%base-packages}, so you need to
25759 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
25760 most applications and libraries look for certificates by default, points
25761 to the certificates installed globally.
25763 Unprivileged users, including users of Guix on a foreign distro,
25764 can also install their own certificate package in
25765 their profile. A number of environment variables need to be defined so
25766 that applications and libraries know where to find them. Namely, the
25767 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
25768 variables. Some applications add their own environment variables; for
25769 instance, the Git version control system honors the certificate bundle
25770 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
25771 would typically run something like:
25774 $ guix install nss-certs
25775 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
25776 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
25777 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
25780 As another example, R requires the @code{CURL_CA_BUNDLE} environment
25781 variable to point to a certificate bundle, so you would have to run
25782 something like this:
25785 $ guix install nss-certs
25786 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
25789 For other applications you may want to look up the required environment
25790 variable in the relevant documentation.
25793 @node Name Service Switch
25794 @section Name Service Switch
25796 @cindex name service switch
25798 The @code{(gnu system nss)} module provides bindings to the
25799 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
25800 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
25801 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
25802 extended with new ``name'' lookup methods for system databases, which
25803 includes host names, service names, user accounts, and more (@pxref{Name
25804 Service Switch, System Databases and Name Service Switch,, libc, The GNU
25805 C Library Reference Manual}).
25807 The NSS configuration specifies, for each system database, which lookup
25808 method is to be used, and how the various methods are chained
25809 together---for instance, under which circumstances NSS should try the
25810 next method in the list. The NSS configuration is given in the
25811 @code{name-service-switch} field of @code{operating-system} declarations
25812 (@pxref{operating-system Reference, @code{name-service-switch}}).
25815 @cindex .local, host name lookup
25816 As an example, the declaration below configures the NSS to use the
25817 @uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
25818 back-end}, which supports host name lookups over multicast DNS (mDNS)
25819 for host names ending in @code{.local}:
25822 (name-service-switch
25823 (hosts (list %files ;first, check /etc/hosts
25825 ;; If the above did not succeed, try
25826 ;; with 'mdns_minimal'.
25828 (name "mdns_minimal")
25830 ;; 'mdns_minimal' is authoritative for
25831 ;; '.local'. When it returns "not found",
25832 ;; no need to try the next methods.
25833 (reaction (lookup-specification
25834 (not-found => return))))
25836 ;; Then fall back to DNS.
25840 ;; Finally, try with the "full" 'mdns'.
25845 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
25846 contains this configuration, so you will not have to type it if all you
25847 want is to have @code{.local} host lookup working.
25849 Note that, in this case, in addition to setting the
25850 @code{name-service-switch} of the @code{operating-system} declaration,
25851 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
25852 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
25853 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
25854 to the name service cache daemon (@pxref{Base Services,
25855 @code{nscd-service}}).
25857 For convenience, the following variables provide typical NSS
25860 @defvr {Scheme Variable} %default-nss
25861 This is the default name service switch configuration, a
25862 @code{name-service-switch} object.
25865 @defvr {Scheme Variable} %mdns-host-lookup-nss
25866 This is the name service switch configuration with support for host name
25867 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
25870 The reference for name service switch configuration is given below. It
25871 is a direct mapping of the configuration file format of the C library , so
25872 please refer to the C library manual for more information (@pxref{NSS
25873 Configuration File,,, libc, The GNU C Library Reference Manual}).
25874 Compared to the configuration file format of libc NSS, it has the advantage
25875 not only of adding this warm parenthetic feel that we like, but also
25876 static checks: you will know about syntax errors and typos as soon as you
25877 run @command{guix system}.
25879 @deftp {Data Type} name-service-switch
25881 This is the data type representation the configuration of libc's name
25882 service switch (NSS). Each field below represents one of the supported
25899 The system databases handled by the NSS. Each of these fields must be a
25900 list of @code{<name-service>} objects (see below).
25904 @deftp {Data Type} name-service
25906 This is the data type representing an actual name service and the
25907 associated lookup action.
25911 A string denoting the name service (@pxref{Services in the NSS
25912 configuration,,, libc, The GNU C Library Reference Manual}).
25914 Note that name services listed here must be visible to nscd. This is
25915 achieved by passing the @code{#:name-services} argument to
25916 @code{nscd-service} the list of packages providing the needed name
25917 services (@pxref{Base Services, @code{nscd-service}}).
25920 An action specified using the @code{lookup-specification} macro
25921 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
25922 Reference Manual}). For example:
25925 (lookup-specification (unavailable => continue)
25926 (success => return))
25931 @node Initial RAM Disk
25932 @section Initial RAM Disk
25935 @cindex initial RAM disk
25936 For bootstrapping purposes, the Linux-Libre kernel is passed an
25937 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
25938 root file system as well as an initialization script. The latter is
25939 responsible for mounting the real root file system, and for loading any
25940 kernel modules that may be needed to achieve that.
25942 The @code{initrd-modules} field of an @code{operating-system}
25943 declaration allows you to specify Linux-libre kernel modules that must
25944 be available in the initrd. In particular, this is where you would list
25945 modules needed to actually drive the hard disk where your root partition
25946 is---although the default value of @code{initrd-modules} should cover
25947 most use cases. For example, assuming you need the @code{megaraid_sas}
25948 module in addition to the default modules to be able to access your root
25949 file system, you would write:
25954 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
25957 @defvr {Scheme Variable} %base-initrd-modules
25958 This is the list of kernel modules included in the initrd by default.
25961 Furthermore, if you need lower-level customization, the @code{initrd}
25962 field of an @code{operating-system} declaration allows
25963 you to specify which initrd you would like to use. The @code{(gnu
25964 system linux-initrd)} module provides three ways to build an initrd: the
25965 high-level @code{base-initrd} procedure and the low-level
25966 @code{raw-initrd} and @code{expression->initrd} procedures.
25968 The @code{base-initrd} procedure is intended to cover most common uses.
25969 For example, if you want to add a bunch of kernel modules to be loaded
25970 at boot time, you can define the @code{initrd} field of the operating
25971 system declaration like this:
25974 (initrd (lambda (file-systems . rest)
25975 ;; Create a standard initrd but set up networking
25976 ;; with the parameters QEMU expects by default.
25977 (apply base-initrd file-systems
25978 #:qemu-networking? #t
25982 The @code{base-initrd} procedure also handles common use cases that
25983 involves using the system as a QEMU guest, or as a ``live'' system with
25984 volatile root file system.
25986 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
25987 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
25988 such as trying to guess which kernel modules and packages should be included
25989 to the initrd. An example use of @code{raw-initrd} is when a user has
25990 a custom Linux kernel configuration and default kernel modules included by
25991 @code{base-initrd} are not available.
25993 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
25994 honors several options passed on the Linux kernel command line
25995 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
25996 @code{-append} option of QEMU), notably:
25999 @item --load=@var{boot}
26000 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
26001 program, once it has mounted the root file system.
26003 Guix uses this option to yield control to a boot program that runs the
26004 service activation programs and then spawns the GNU@tie{}Shepherd, the
26005 initialization system.
26007 @item --root=@var{root}
26008 Mount @var{root} as the root file system. @var{root} can be a
26009 device name like @code{/dev/sda1}, a file system label, or a file system
26012 @item --system=@var{system}
26013 Have @file{/run/booted-system} and @file{/run/current-system} point to
26016 @item modprobe.blacklist=@var{modules}@dots{}
26017 @cindex module, black-listing
26018 @cindex black list, of kernel modules
26019 Instruct the initial RAM disk as well as the @command{modprobe} command
26020 (from the kmod package) to refuse to load @var{modules}. @var{modules}
26021 must be a comma-separated list of module names---e.g.,
26022 @code{usbkbd,9pnet}.
26025 Start a read-eval-print loop (REPL) from the initial RAM disk before it
26026 tries to load kernel modules and to mount the root file system. Our
26027 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
26028 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
26029 Manual}, for more information on Guile's REPL.
26033 Now that you know all the features that initial RAM disks produced by
26034 @code{base-initrd} and @code{raw-initrd} provide,
26035 here is how to use it and customize it further.
26038 @cindex initial RAM disk
26039 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
26040 [#:linux-modules '()] [#:mapped-devices '()] @
26041 [#:keyboard-layout #f] @
26042 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
26043 Return a derivation that builds a raw initrd. @var{file-systems} is
26044 a list of file systems to be mounted by the initrd, possibly in addition to
26045 the root file system specified on the kernel command line via @code{--root}.
26046 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
26047 @var{mapped-devices} is a list of device mappings to realize before
26048 @var{file-systems} are mounted (@pxref{Mapped Devices}).
26049 @var{helper-packages} is a list of packages to be copied in the initrd. It may
26050 include @code{e2fsck/static} or other packages needed by the initrd to check
26051 the root file system.
26053 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26054 the desired console keyboard layout. This is done before @var{mapped-devices}
26055 are set up and before @var{file-systems} are mounted such that, should the
26056 user need to enter a passphrase or use the REPL, this happens using the
26057 intended keyboard layout.
26059 When @var{qemu-networking?} is true, set up networking with the standard QEMU
26060 parameters. When @var{virtio?} is true, load additional modules so that the
26061 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
26063 When @var{volatile-root?} is true, the root file system is writable but any changes
26067 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
26068 [#:mapped-devices '()] [#:keyboard-layout #f] @
26069 [#:qemu-networking? #f] [#:volatile-root? #f] @
26070 [#:linux-modules '()]
26071 Return as a file-like object a generic initrd, with kernel
26072 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
26073 mounted by the initrd, possibly in addition to the root file system specified
26074 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
26075 mappings to realize before @var{file-systems} are mounted.
26077 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26078 the desired console keyboard layout. This is done before @var{mapped-devices}
26079 are set up and before @var{file-systems} are mounted such that, should the
26080 user need to enter a passphrase or use the REPL, this happens using the
26081 intended keyboard layout.
26083 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
26085 The initrd is automatically populated with all the kernel modules necessary
26086 for @var{file-systems} and for the given options. Additional kernel
26087 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
26088 loaded at boot time in the order in which they appear.
26091 Needless to say, the initrds we produce and use embed a
26092 statically-linked Guile, and the initialization program is a Guile
26093 program. That gives a lot of flexibility. The
26094 @code{expression->initrd} procedure builds such an initrd, given the
26095 program to run in that initrd.
26097 @deffn {Scheme Procedure} expression->initrd @var{exp} @
26098 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
26099 Return as a file-like object a Linux initrd (a gzipped cpio archive)
26100 containing @var{guile} and that evaluates @var{exp}, a G-expression,
26101 upon booting. All the derivations referenced by @var{exp} are
26102 automatically copied to the initrd.
26105 @node Bootloader Configuration
26106 @section Bootloader Configuration
26109 @cindex boot loader
26111 The operating system supports multiple bootloaders. The bootloader is
26112 configured using @code{bootloader-configuration} declaration. All the
26113 fields of this structure are bootloader agnostic except for one field,
26114 @code{bootloader} that indicates the bootloader to be configured and
26117 Some of the bootloaders do not honor every field of
26118 @code{bootloader-configuration}. For instance, the extlinux
26119 bootloader does not support themes and thus ignores the @code{theme}
26122 @deftp {Data Type} bootloader-configuration
26123 The type of a bootloader configuration declaration.
26127 @item @code{bootloader}
26128 @cindex EFI, bootloader
26129 @cindex UEFI, bootloader
26130 @cindex BIOS, bootloader
26131 The bootloader to use, as a @code{bootloader} object. For now
26132 @code{grub-bootloader}, @code{grub-efi-bootloader},
26133 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
26135 @vindex grub-efi-bootloader
26136 @code{grub-efi-bootloader} allows to boot on modern systems using the
26137 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
26138 use if the installation image contains a @file{/sys/firmware/efi} directory
26139 when you boot it on your system.
26141 @vindex grub-bootloader
26142 @code{grub-bootloader} allows you to boot in particular Intel-based machines
26143 in ``legacy'' BIOS mode.
26145 @cindex ARM, bootloaders
26146 @cindex AArch64, bootloaders
26147 Available bootloaders are described in @code{(gnu bootloader @dots{})}
26148 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
26149 of bootloaders for a wide range of ARM and AArch64 systems, using the
26150 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
26152 @item @code{target}
26153 This is a string denoting the target onto which to install the
26156 The interpretation depends on the bootloader in question. For
26157 @code{grub-bootloader}, for example, it should be a device name understood by
26158 the bootloader @command{installer} command, such as @code{/dev/sda} or
26159 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
26160 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
26161 system, usually @file{/boot/efi}.
26163 @item @code{menu-entries} (default: @code{()})
26164 A possibly empty list of @code{menu-entry} objects (see below), denoting
26165 entries to appear in the bootloader menu, in addition to the current
26166 system entry and the entry pointing to previous system generations.
26168 @item @code{default-entry} (default: @code{0})
26169 The index of the default boot menu entry. Index 0 is for the entry of the
26172 @item @code{timeout} (default: @code{5})
26173 The number of seconds to wait for keyboard input before booting. Set to
26174 0 to boot immediately, and to -1 to wait indefinitely.
26176 @cindex keyboard layout, for the bootloader
26177 @item @code{keyboard-layout} (default: @code{#f})
26178 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
26179 layout, usually US@tie{}English (``qwerty'').
26181 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
26185 This option is currently ignored by bootloaders other than @code{grub} and
26189 @item @code{theme} (default: @var{#f})
26190 The bootloader theme object describing the theme to use. If no theme
26191 is provided, some bootloaders might use a default theme, that's true
26194 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
26195 The output terminals used for the bootloader boot menu, as a list of
26196 symbols. GRUB accepts the values: @code{console}, @code{serial},
26197 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
26198 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
26199 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
26200 configuration,,, grub,GNU GRUB manual}).
26202 @item @code{terminal-inputs} (default: @code{'()})
26203 The input terminals used for the bootloader boot menu, as a list of
26204 symbols. For GRUB, the default is the native platform terminal as
26205 determined at run-time. GRUB accepts the values: @code{console},
26206 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
26207 @code{usb_keyboard}. This field corresponds to the GRUB variable
26208 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
26211 @item @code{serial-unit} (default: @code{#f})
26212 The serial unit used by the bootloader, as an integer from 0 to 3.
26213 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
26214 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26216 @item @code{serial-speed} (default: @code{#f})
26217 The speed of the serial interface, as an integer. For GRUB, the
26218 default value is chosen at run-time; currently GRUB chooses
26219 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26226 Should you want to list additional boot menu entries @i{via} the
26227 @code{menu-entries} field above, you will need to create them with the
26228 @code{menu-entry} form. For example, imagine you want to be able to
26229 boot another distro (hard to imagine!), you can define a menu entry
26234 (label "The Other Distro")
26235 (linux "/boot/old/vmlinux-2.6.32")
26236 (linux-arguments '("root=/dev/sda2"))
26237 (initrd "/boot/old/initrd"))
26242 @deftp {Data Type} menu-entry
26243 The type of an entry in the bootloader menu.
26248 The label to show in the menu---e.g., @code{"GNU"}.
26251 The Linux kernel image to boot, for example:
26254 (file-append linux-libre "/bzImage")
26257 For GRUB, it is also possible to specify a device explicitly in the
26258 file path using GRUB's device naming convention (@pxref{Naming
26259 convention,,, grub, GNU GRUB manual}), for example:
26262 "(hd0,msdos1)/boot/vmlinuz"
26265 If the device is specified explicitly as above, then the @code{device}
26266 field is ignored entirely.
26268 @item @code{linux-arguments} (default: @code{()})
26269 The list of extra Linux kernel command-line arguments---e.g.,
26270 @code{("console=ttyS0")}.
26272 @item @code{initrd}
26273 A G-Expression or string denoting the file name of the initial RAM disk
26274 to use (@pxref{G-Expressions}).
26275 @item @code{device} (default: @code{#f})
26276 The device where the kernel and initrd are to be found---i.e., for GRUB,
26277 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
26279 This may be a file system label (a string), a file system UUID (a
26280 bytevector, @pxref{File Systems}), or @code{#f}, in which case
26281 the bootloader will search the device containing the file specified by
26282 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
26283 must @emph{not} be an OS device name such as @file{/dev/sda1}.
26291 @c FIXME: Write documentation once it's stable.
26292 For now only GRUB has theme support. GRUB themes are created using
26293 the @code{grub-theme} form, which is not fully documented yet.
26295 @deftp {Data Type} grub-theme
26296 Data type representing the configuration of the GRUB theme.
26299 @item @code{gfxmode} (default: @code{'("auto")})
26300 The GRUB @code{gfxmode} to set (a list of screen resolution strings, see
26301 @pxref{gfxmode,,, grub, GNU GRUB manual}).
26305 @defvr {Scheme Variable} %default-theme
26306 This is the default GRUB theme used by the operating system if no
26307 @code{theme} field is specified in @code{bootloader-configuration}
26310 It comes with a fancy background image displaying the GNU and Guix
26314 For example, to override the default resolution, you may use something
26319 (grub-configuration
26322 (inherit %default-theme)
26323 (gfxmode '("1024x786x32" "auto"))))))
26326 @node Invoking guix system
26327 @section Invoking @code{guix system}
26329 Once you have written an operating system declaration as seen in the
26330 previous section, it can be @dfn{instantiated} using the @command{guix
26331 system} command. The synopsis is:
26334 guix system @var{options}@dots{} @var{action} @var{file}
26337 @var{file} must be the name of a file containing an
26338 @code{operating-system} declaration. @var{action} specifies how the
26339 operating system is instantiated. Currently the following values are
26344 Display available service type definitions that match the given regular
26345 expressions, sorted by relevance:
26351 $ guix system search console
26352 name: console-fonts
26353 location: gnu/services/base.scm:806:2
26354 extends: shepherd-root
26355 description: Install the given fonts on the specified ttys (fonts are per
26356 + virtual console on GNU/Linux). The value of this service is a list of
26357 + tty/font pairs. The font can be the name of a font provided by the `kbd'
26358 + package or any valid argument to `setfont', as in this example:
26360 + '(("tty1" . "LatGrkCyr-8x16")
26361 + ("tty2" . (file-append
26363 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
26364 + ("tty3" . (file-append
26366 + "/share/consolefonts/ter-132n"))) ; for HDPI
26370 location: gnu/services/base.scm:1190:2
26371 extends: shepherd-root
26372 description: Provide console login using the `mingetty' program.
26376 location: gnu/services/base.scm:860:2
26378 description: Provide a console log-in service as specified by its
26379 + configuration value, a `login-configuration' object.
26385 As for @command{guix package --search}, the result is written in
26386 @code{recutils} format, which makes it easy to filter the output
26387 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
26390 Build the operating system described in @var{file}, activate it, and
26391 switch to it@footnote{This action (and the related actions
26392 @code{switch-generation} and @code{roll-back}) are usable only on
26393 systems already running Guix System.}.
26396 @c The paragraph below refers to the problem discussed at
26397 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
26398 It is highly recommended to run @command{guix pull} once before you run
26399 @command{guix system reconfigure} for the first time (@pxref{Invoking
26400 guix pull}). Failing to do that you would see an older version of Guix
26401 once @command{reconfigure} has completed.
26404 This effects all the configuration specified in @var{file}: user
26405 accounts, system services, global package list, setuid programs, etc.
26406 The command starts system services specified in @var{file} that are not
26407 currently running; if a service is currently running this command will
26408 arrange for it to be upgraded the next time it is stopped (e.g.@: by
26409 @code{herd stop X} or @code{herd restart X}).
26411 This command creates a new generation whose number is one greater than
26412 the current generation (as reported by @command{guix system
26413 list-generations}). If that generation already exists, it will be
26414 overwritten. This behavior mirrors that of @command{guix package}
26415 (@pxref{Invoking guix package}).
26417 It also adds a bootloader menu entry for the new OS configuration,
26418 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
26419 entries for older configurations to a submenu, allowing you to choose
26420 an older system generation at boot time should you need it.
26422 @cindex provenance tracking, of the operating system
26423 Upon completion, the new system is deployed under
26424 @file{/run/current-system}. This directory contains @dfn{provenance
26425 meta-data}: the list of channels in use (@pxref{Channels}) and
26426 @var{file} itself, when available. This information is useful should
26427 you later want to inspect how this particular generation was built.
26429 In fact, assuming @var{file} is self-contained, you can later rebuild
26430 generation @var{n} of your operating system with:
26433 guix time-machine \
26434 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
26435 system reconfigure \
26436 /var/guix/profiles/system-@var{n}-link/configuration.scm
26439 You can think of it as some sort of built-in version control! Your
26440 system is not just a binary artifact: @emph{it carries its own source}.
26441 @xref{Service Reference, @code{provenance-service-type}}, for more
26442 information on provenance tracking.
26444 @item switch-generation
26445 @cindex generations
26446 Switch to an existing system generation. This action atomically
26447 switches the system profile to the specified system generation. It
26448 also rearranges the system's existing bootloader menu entries. It
26449 makes the menu entry for the specified system generation the default,
26450 and it moves the entries for the other generatiors to a submenu, if
26451 supported by the bootloader being used. The next time the system
26452 boots, it will use the specified system generation.
26454 The bootloader itself is not being reinstalled when using this
26455 command. Thus, the installed bootloader is used with an updated
26456 configuration file.
26458 The target generation can be specified explicitly by its generation
26459 number. For example, the following invocation would switch to system
26463 guix system switch-generation 7
26466 The target generation can also be specified relative to the current
26467 generation with the form @code{+N} or @code{-N}, where @code{+3} means
26468 ``3 generations ahead of the current generation,'' and @code{-1} means
26469 ``1 generation prior to the current generation.'' When specifying a
26470 negative value such as @code{-1}, you must precede it with @code{--} to
26471 prevent it from being parsed as an option. For example:
26474 guix system switch-generation -- -1
26477 Currently, the effect of invoking this action is @emph{only} to switch
26478 the system profile to an existing generation and rearrange the
26479 bootloader menu entries. To actually start using the target system
26480 generation, you must reboot after running this action. In the future,
26481 it will be updated to do the same things as @command{reconfigure},
26482 like activating and deactivating services.
26484 This action will fail if the specified generation does not exist.
26487 @cindex rolling back
26488 Switch to the preceding system generation. The next time the system
26489 boots, it will use the preceding system generation. This is the inverse
26490 of @command{reconfigure}, and it is exactly the same as invoking
26491 @command{switch-generation} with an argument of @code{-1}.
26493 Currently, as with @command{switch-generation}, you must reboot after
26494 running this action to actually start using the preceding system
26497 @item delete-generations
26498 @cindex deleting system generations
26499 @cindex saving space
26500 Delete system generations, making them candidates for garbage collection
26501 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
26504 This works in the same way as @command{guix package --delete-generations}
26505 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
26506 arguments, all system generations but the current one are deleted:
26509 guix system delete-generations
26512 You can also select the generations you want to delete. The example below
26513 deletes all the system generations that are more than two month old:
26516 guix system delete-generations 2m
26519 Running this command automatically reinstalls the bootloader with an updated
26520 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
26521 longer lists the generations that have been deleted.
26524 Build the derivation of the operating system, which includes all the
26525 configuration files and programs needed to boot and run the system.
26526 This action does not actually install anything.
26529 Populate the given directory with all the files necessary to run the
26530 operating system specified in @var{file}. This is useful for first-time
26531 installations of Guix System. For instance:
26534 guix system init my-os-config.scm /mnt
26537 copies to @file{/mnt} all the store items required by the configuration
26538 specified in @file{my-os-config.scm}. This includes configuration
26539 files, packages, and so on. It also creates other essential files
26540 needed for the system to operate correctly---e.g., the @file{/etc},
26541 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
26543 This command also installs bootloader on the target specified in
26544 @file{my-os-config}, unless the @option{--no-bootloader} option was
26548 @cindex virtual machine
26550 @anchor{guix system vm}
26551 Build a virtual machine that contains the operating system declared in
26552 @var{file}, and return a script to run that virtual machine (VM).
26555 The @code{vm} action and others below
26556 can use KVM support in the Linux-libre kernel. Specifically, if the
26557 machine has hardware virtualization support, the corresponding
26558 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
26559 must exist and be readable and writable by the user and by the
26560 build users of the daemon (@pxref{Build Environment Setup}).
26563 Arguments given to the script are passed to QEMU as in the example
26564 below, which enables networking and requests 1@tie{}GiB of RAM for the
26568 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
26571 The VM shares its store with the host system.
26573 Additional file systems can be shared between the host and the VM using
26574 the @code{--share} and @code{--expose} command-line options: the former
26575 specifies a directory to be shared with write access, while the latter
26576 provides read-only access to the shared directory.
26578 The example below creates a VM in which the user's home directory is
26579 accessible read-only, and where the @file{/exchange} directory is a
26580 read-write mapping of @file{$HOME/tmp} on the host:
26583 guix system vm my-config.scm \
26584 --expose=$HOME --share=$HOME/tmp=/exchange
26587 On GNU/Linux, the default is to boot directly to the kernel; this has
26588 the advantage of requiring only a very tiny root disk image since the
26589 store of the host can then be mounted.
26591 The @code{--full-boot} option forces a complete boot sequence, starting
26592 with the bootloader. This requires more disk space since a root image
26593 containing at least the kernel, initrd, and bootloader data files must
26594 be created. The @code{--image-size} option can be used to specify the
26597 @cindex System images, creation in various formats
26598 @cindex Creating system images in various formats
26601 @itemx docker-image
26602 Return a virtual machine, disk image, or Docker image of the operating
26603 system declared in @var{file} that stands alone. By default,
26604 @command{guix system} estimates the size of the image needed to store
26605 the system, but you can use the @option{--image-size} option to specify
26606 a value. Docker images are built to contain exactly what they need, so
26607 the @option{--image-size} option is ignored in the case of
26608 @code{docker-image}.
26610 You can specify the root file system type by using the
26611 @option{--file-system-type} option. It defaults to @code{ext4}.
26613 When using @code{vm-image}, the returned image is in qcow2 format, which
26614 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
26615 for more information on how to run the image in a virtual machine.
26617 When using @code{disk-image}, a raw disk image is produced; it can be
26618 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
26619 the device corresponding to a USB stick, one can copy the image to it
26620 using the following command:
26623 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
26626 When using @code{docker-image}, a Docker image is produced. Guix builds
26627 the image from scratch, not from a pre-existing Docker base image. As a
26628 result, it contains @emph{exactly} what you define in the operating
26629 system configuration file. You can then load the image and launch a
26630 Docker container using commands like the following:
26633 image_id="`docker load < guix-system-docker-image.tar.gz`"
26634 container_id="`docker create $image_id`"
26635 docker start $container_id
26638 This command starts a new Docker container from the specified image. It
26639 will boot the Guix system in the usual manner, which means it will
26640 start any services you have defined in the operating system
26641 configuration. You can get an interactive shell running in the container
26642 using @command{docker exec}:
26645 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
26648 Depending on what you run in the Docker container, it
26649 may be necessary to give the container additional permissions. For
26650 example, if you intend to build software using Guix inside of the Docker
26651 container, you may need to pass the @option{--privileged} option to
26652 @code{docker create}.
26655 Return a script to run the operating system declared in @var{file}
26656 within a container. Containers are a set of lightweight isolation
26657 mechanisms provided by the kernel Linux-libre. Containers are
26658 substantially less resource-demanding than full virtual machines since
26659 the kernel, shared objects, and other resources can be shared with the
26660 host system; this also means they provide thinner isolation.
26662 Currently, the script must be run as root in order to support more than
26663 a single user and group. The container shares its store with the host
26666 As with the @code{vm} action (@pxref{guix system vm}), additional file
26667 systems to be shared between the host and container can be specified
26668 using the @option{--share} and @option{--expose} options:
26671 guix system container my-config.scm \
26672 --expose=$HOME --share=$HOME/tmp=/exchange
26676 This option requires Linux-libre 3.19 or newer.
26681 @var{options} can contain any of the common build options (@pxref{Common
26682 Build Options}). In addition, @var{options} can contain one of the
26686 @item --expression=@var{expr}
26687 @itemx -e @var{expr}
26688 Consider the operating-system @var{expr} evaluates to.
26689 This is an alternative to specifying a file which evaluates to an
26691 This is used to generate the Guix system installer @pxref{Building the
26692 Installation Image}).
26694 @item --system=@var{system}
26695 @itemx -s @var{system}
26696 Attempt to build for @var{system} instead of the host system type.
26697 This works as per @command{guix build} (@pxref{Invoking guix build}).
26701 Return the derivation file name of the given operating system without
26704 @cindex provenance tracking, of the operating system
26705 @item --save-provenance
26706 As discussed above, @command{guix system init} and @command{guix system
26707 reconfigure} always save provenance information @i{via} a dedicated
26708 service (@pxref{Service Reference, @code{provenance-service-type}}).
26709 However, other commands don't do that by default. If you wish to, say,
26710 create a virtual machine image that contains provenance information, you
26714 guix system vm-image --save-provenance config.scm
26717 That way, the resulting image will effectively ``embed its own source''
26718 in the form of meta-data in @file{/run/current-system}. With that
26719 information, one can rebuild the image to make sure it really contains
26720 what it pretends to contain; or they could use that to derive a variant
26723 @item --file-system-type=@var{type}
26724 @itemx -t @var{type}
26725 For the @code{disk-image} action, create a file system of the given
26726 @var{type} on the image.
26728 When this option is omitted, @command{guix system} uses @code{ext4}.
26730 @cindex ISO-9660 format
26731 @cindex CD image format
26732 @cindex DVD image format
26733 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
26734 for burning on CDs and DVDs.
26736 @item --image-size=@var{size}
26737 For the @code{vm-image} and @code{disk-image} actions, create an image
26738 of the given @var{size}. @var{size} may be a number of bytes, or it may
26739 include a unit as a suffix (@pxref{Block size, size specifications,,
26740 coreutils, GNU Coreutils}).
26742 When this option is omitted, @command{guix system} computes an estimate
26743 of the image size as a function of the size of the system declared in
26748 For the @code{container} action, allow containers to access the host network,
26749 that is, do not create a network namespace.
26751 @item --root=@var{file}
26752 @itemx -r @var{file}
26753 Make @var{file} a symlink to the result, and register it as a garbage
26756 @item --skip-checks
26757 Skip pre-installation safety checks.
26759 By default, @command{guix system init} and @command{guix system
26760 reconfigure} perform safety checks: they make sure the file systems that
26761 appear in the @code{operating-system} declaration actually exist
26762 (@pxref{File Systems}), and that any Linux kernel modules that may be
26763 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
26764 RAM Disk}). Passing this option skips these tests altogether.
26767 @cindex on-error strategy
26768 @cindex error strategy
26769 @item --on-error=@var{strategy}
26770 Apply @var{strategy} when an error occurs when reading @var{file}.
26771 @var{strategy} may be one of the following:
26774 @item nothing-special
26775 Report the error concisely and exit. This is the default strategy.
26778 Likewise, but also display a backtrace.
26781 Report the error and enter Guile's debugger. From there, you can run
26782 commands such as @code{,bt} to get a backtrace, @code{,locals} to
26783 display local variable values, and more generally inspect the state of the
26784 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
26785 a list of available debugging commands.
26789 Once you have built, configured, re-configured, and re-re-configured
26790 your Guix installation, you may find it useful to list the operating
26791 system generations available on disk---and that you can choose from the
26792 bootloader boot menu:
26797 Describe the current system generation: its file name, the kernel and
26798 bootloader used, etc., as well as provenance information when available.
26800 @item list-generations
26801 List a summary of each generation of the operating system available on
26802 disk, in a human-readable way. This is similar to the
26803 @option{--list-generations} option of @command{guix package}
26804 (@pxref{Invoking guix package}).
26806 Optionally, one can specify a pattern, with the same syntax that is used
26807 in @command{guix package --list-generations}, to restrict the list of
26808 generations displayed. For instance, the following command displays
26809 generations that are up to 10 days old:
26812 $ guix system list-generations 10d
26817 The @command{guix system} command has even more to offer! The following
26818 sub-commands allow you to visualize how your system services relate to
26821 @anchor{system-extension-graph}
26824 @item extension-graph
26825 Emit in Dot/Graphviz format to standard output the @dfn{service
26826 extension graph} of the operating system defined in @var{file}
26827 (@pxref{Service Composition}, for more information on service
26833 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
26836 produces a PDF file showing the extension relations among services.
26838 @anchor{system-shepherd-graph}
26839 @item shepherd-graph
26840 Emit in Dot/Graphviz format to standard output the @dfn{dependency
26841 graph} of shepherd services of the operating system defined in
26842 @var{file}. @xref{Shepherd Services}, for more information and for an
26847 @node Invoking guix deploy
26848 @section Invoking @code{guix deploy}
26850 We've already seen @code{operating-system} declarations used to manage a
26851 machine's configuration locally. Suppose you need to configure multiple
26852 machines, though---perhaps you're managing a service on the web that's
26853 comprised of several servers. @command{guix deploy} enables you to use those
26854 same @code{operating-system} declarations to manage multiple remote hosts at
26855 once as a logical ``deployment''.
26858 The functionality described in this section is still under development
26859 and is subject to change. Get in touch with us on
26860 @email{guix-devel@@gnu.org}!
26864 guix deploy @var{file}
26867 Such an invocation will deploy the machines that the code within @var{file}
26868 evaluates to. As an example, @var{file} might contain a definition like this:
26871 ;; This is a Guix deployment of a "bare bones" setup, with
26872 ;; no X11 display server, to a machine with an SSH daemon
26873 ;; listening on localhost:2222. A configuration such as this
26874 ;; may be appropriate for virtual machine with ports
26875 ;; forwarded to the host's loopback interface.
26877 (use-service-modules networking ssh)
26878 (use-package-modules bootloaders)
26882 (host-name "gnu-deployed")
26883 (timezone "Etc/UTC")
26884 (bootloader (bootloader-configuration
26885 (bootloader grub-bootloader)
26886 (target "/dev/vda")
26887 (terminal-outputs '(console))))
26888 (file-systems (cons (file-system
26890 (device "/dev/vda1")
26892 %base-file-systems))
26894 (append (list (service dhcp-client-service-type)
26895 (service openssh-service-type
26896 (openssh-configuration
26897 (permit-root-login #t)
26898 (allow-empty-passwords? #t))))
26902 (operating-system %system)
26903 (environment managed-host-environment-type)
26904 (configuration (machine-ssh-configuration
26905 (host-name "localhost")
26906 (system "x86_64-linux")
26908 (identity "./id_rsa")
26912 The file should evaluate to a list of @var{machine} objects. This example,
26913 upon being deployed, will create a new generation on the remote system
26914 realizing the @code{operating-system} declaration @var{%system}.
26915 @var{environment} and @var{configuration} specify how the machine should be
26916 provisioned---that is, how the computing resources should be created and
26917 managed. The above example does not create any resources, as a
26918 @code{'managed-host} is a machine that is already running the Guix system and
26919 available over the network. This is a particularly simple case; a more
26920 complex deployment may involve, for example, starting virtual machines through
26921 a Virtual Private Server (VPS) provider. In such a case, a different
26922 @var{environment} type would be used.
26924 Do note that you first need to generate a key pair on the coordinator machine
26925 to allow the daemon to export signed archives of files from the store
26926 (@pxref{Invoking guix archive}).
26929 # guix archive --generate-key
26933 Each target machine must authorize the key of the master machine so that it
26934 accepts store items it receives from the coordinator:
26937 # guix archive --authorize < coordinator-public-key.txt
26940 @code{user}, in this example, specifies the name of the user account to log in
26941 as to perform the deployment. Its default value is @code{root}, but root
26942 login over SSH may be forbidden in some cases. To work around this,
26943 @command{guix deploy} can log in as an unprivileged user and employ
26944 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
26945 currently installed on the remote and can be invoked non-interactively as
26946 @code{user}. That is: the line in @code{sudoers} granting @code{user} the
26947 ability to use @code{sudo} must contain the @code{NOPASSWD} tag.
26949 @deftp {Data Type} machine
26950 This is the data type representing a single machine in a heterogeneous Guix
26954 @item @code{operating-system}
26955 The object of the operating system configuration to deploy.
26957 @item @code{environment}
26958 An @code{environment-type} describing how the machine should be provisioned.
26960 @item @code{configuration} (default: @code{#f})
26961 An object describing the configuration for the machine's @code{environment}.
26962 If the @code{environment} has a default configuration, @code{#f} may be used.
26963 If @code{#f} is used for an environment with no default configuration,
26964 however, an error will be thrown.
26968 @deftp {Data Type} machine-ssh-configuration
26969 This is the data type representing the SSH client parameters for a machine
26970 with an @code{environment} of @code{managed-host-environment-type}.
26973 @item @code{host-name}
26974 @item @code{build-locally?} (default: @code{#t})
26975 If false, system derivations will be built on the machine being deployed to.
26976 @item @code{system}
26977 The system type describing the architecture of the machine being deployed
26978 to---e.g., @code{"x86_64-linux"}.
26979 @item @code{authorize?} (default: @code{#t})
26980 If true, the coordinator's signing key will be added to the remote's ACL
26982 @item @code{port} (default: @code{22})
26983 @item @code{user} (default: @code{"root"})
26984 @item @code{identity} (default: @code{#f})
26985 If specified, the path to the SSH private key to use to authenticate with the
26988 @item @code{host-key} (default: @code{#f})
26989 This should be the SSH host key of the machine, which looks like this:
26992 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
26995 When @code{host-key} is @code{#f}, the server is authenticated against
26996 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
27002 @deftp {Data Type} digital-ocean-configuration
27003 This is the data type describing the Droplet that should be created for a
27004 machine with an @code{environment} of @code{digital-ocean-environment-type}.
27007 @item @code{ssh-key}
27008 The path to the SSH private key to use to authenticate with the remote
27009 host. In the future, this field may not exist.
27011 A list of string ``tags'' that uniquely identify the machine. Must be given
27012 such that no two machines in the deployment have the same set of tags.
27013 @item @code{region}
27014 A Digital Ocean region slug, such as @code{"nyc3"}.
27016 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
27017 @item @code{enable-ipv6?}
27018 Whether or not the droplet should be created with IPv6 networking.
27022 @node Running Guix in a VM
27023 @section Running Guix in a Virtual Machine
27025 @cindex virtual machine
27026 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
27028 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
27029 This image is a compressed image in QCOW format. You will first need to
27030 decompress with @command{xz -d}, and then you can pass it to an emulator such
27031 as QEMU (see below for details).
27033 This image boots the Xfce graphical environment and it contains some
27034 commonly-used tools. You can install more software in the image by running
27035 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
27036 also reconfigure the system based on its initial configuration file available
27037 as @file{/etc/config.scm} (@pxref{Using the Configuration System}).
27039 Instead of using this pre-built image, one can also build their own virtual
27040 machine image using @command{guix system vm-image} (@pxref{Invoking guix
27041 system}). The returned image is in qcow2 format, which the
27042 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
27045 If you built your own image, you must copy it out of the store
27046 (@pxref{The Store}) and give yourself permission to write to the copy
27047 before you can use it. When invoking QEMU, you must choose a system
27048 emulator that is suitable for your hardware platform. Here is a minimal
27049 QEMU invocation that will boot the result of @command{guix system
27050 vm-image} on x86_64 hardware:
27053 $ qemu-system-x86_64 \
27054 -nic user,model=virtio-net-pci \
27055 -enable-kvm -m 1024 \
27056 -device virtio-blk,drive=myhd \
27057 -drive if=none,file=/tmp/qemu-image,id=myhd
27060 Here is what each of these options means:
27063 @item qemu-system-x86_64
27064 This specifies the hardware platform to emulate. This should match the
27067 @item -nic user,model=virtio-net-pci
27068 Enable the unprivileged user-mode network stack. The guest OS can
27069 access the host but not vice versa. This is the simplest way to get the
27070 guest OS online. @code{model} specifies which network device to emulate:
27071 @code{virtio-net-pci} is a special device made for virtualized operating
27072 systems and recommended for most uses. Assuming your hardware platform is
27073 x86_64, you can get a list of available NIC models by running
27074 @command{qemu-system-x86_64 -nic model=help}.
27077 If your system has hardware virtualization extensions, enabling the
27078 virtual machine support (KVM) of the Linux kernel will make things run
27081 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
27083 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
27084 which may be insufficient for some operations.
27086 @item -device virtio-blk,drive=myhd
27087 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
27088 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
27089 better performance than if it were emulating a complete disk drive. See the
27090 QEMU and KVM documentation for more info.
27092 @item -drive if=none,file=/tmp/qemu-image,id=myhd
27093 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
27094 the ``myhd'' drive.
27097 The default @command{run-vm.sh} script that is returned by an invocation of
27098 @command{guix system vm} does not add a @command{-nic user} flag by default.
27099 To get network access from within the vm add the @code{(dhcp-client-service)}
27100 to your system definition and start the VM using
27101 @command{`guix system vm config.scm` -nic user}. An important caveat of using
27102 @command{-nic user} for networking is that @command{ping} will not work, because
27103 it uses the ICMP protocol. You'll have to use a different command to check for
27104 network connectivity, for example @command{guix download}.
27106 @subsection Connecting Through SSH
27110 To enable SSH inside a VM you need to add an SSH server like
27111 @code{openssh-service-type} to your VM (@pxref{Networking Services,
27112 @code{openssh-service-type}}). In addition you need to forward the SSH port,
27113 22 by default, to the host. You can do this with
27116 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
27119 To connect to the VM you can run
27122 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
27125 The @command{-p} tells @command{ssh} the port you want to connect to.
27126 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
27127 every time you modify your @command{config.scm} file and the
27128 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
27129 connection to an unknown host every time you connect.
27131 @subsection Using @command{virt-viewer} with Spice
27133 As an alternative to the default @command{qemu} graphical client you can
27134 use the @command{remote-viewer} from the @command{virt-viewer} package. To
27135 connect pass the @command{-spice port=5930,disable-ticketing} flag to
27136 @command{qemu}. See previous section for further information on how to do this.
27138 Spice also allows you to do some nice stuff like share your clipboard with your
27139 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
27142 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
27143 -chardev spicevmc,name=vdagent,id=vdagent
27144 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
27145 name=com.redhat.spice.0
27148 You'll also need to add the @pxref{Miscellaneous Services, Spice service}.
27150 @node Defining Services
27151 @section Defining Services
27153 The previous sections show the available services and how one can combine
27154 them in an @code{operating-system} declaration. But how do we define
27155 them in the first place? And what is a service anyway?
27158 * Service Composition:: The model for composing services.
27159 * Service Types and Services:: Types and services.
27160 * Service Reference:: API reference.
27161 * Shepherd Services:: A particular type of service.
27164 @node Service Composition
27165 @subsection Service Composition
27169 Here we define a @dfn{service} as, broadly, something that extends the
27170 functionality of the operating system. Often a service is a process---a
27171 @dfn{daemon}---started when the system boots: a secure shell server, a
27172 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
27173 whose execution can be triggered by another daemon---e.g., an FTP server
27174 started by @command{inetd} or a D-Bus service activated by
27175 @command{dbus-daemon}. Occasionally, a service does not map to a
27176 daemon. For instance, the ``account'' service collects user accounts
27177 and makes sure they exist when the system runs; the ``udev'' service
27178 collects device management rules and makes them available to the eudev
27179 daemon; the @file{/etc} service populates the @file{/etc} directory
27182 @cindex service extensions
27183 Guix system services are connected by @dfn{extensions}. For instance, the
27184 secure shell service @emph{extends} the Shepherd---the
27185 initialization system, running as PID@tie{}1---by giving it the command
27186 lines to start and stop the secure shell daemon (@pxref{Networking
27187 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
27188 service by passing it its @file{.service} specification, and extends the
27189 udev service by passing it device management rules (@pxref{Desktop
27190 Services, @code{upower-service}}); the Guix daemon service extends the
27191 Shepherd by passing it the command lines to start and stop the daemon,
27192 and extends the account service by passing it a list of required build
27193 user accounts (@pxref{Base Services}).
27195 All in all, services and their ``extends'' relations form a directed
27196 acyclic graph (DAG). If we represent services as boxes and extensions
27197 as arrows, a typical system might provide something like this:
27199 @image{images/service-graph,,5in,Typical service extension graph.}
27201 @cindex system service
27202 At the bottom, we see the @dfn{system service}, which produces the
27203 directory containing everything to run and boot the system, as returned
27204 by the @command{guix system build} command. @xref{Service Reference},
27205 to learn about the other service types shown here.
27206 @xref{system-extension-graph, the @command{guix system extension-graph}
27207 command}, for information on how to generate this representation for a
27208 particular operating system definition.
27210 @cindex service types
27211 Technically, developers can define @dfn{service types} to express these
27212 relations. There can be any number of services of a given type on the
27213 system---for instance, a system running two instances of the GNU secure
27214 shell server (lsh) has two instances of @code{lsh-service-type}, with
27215 different parameters.
27217 The following section describes the programming interface for service
27218 types and services.
27220 @node Service Types and Services
27221 @subsection Service Types and Services
27223 A @dfn{service type} is a node in the DAG described above. Let us start
27224 with a simple example, the service type for the Guix build daemon
27225 (@pxref{Invoking guix-daemon}):
27228 (define guix-service-type
27232 (list (service-extension shepherd-root-service-type guix-shepherd-service)
27233 (service-extension account-service-type guix-accounts)
27234 (service-extension activation-service-type guix-activation)))
27235 (default-value (guix-configuration))))
27239 It defines three things:
27243 A name, whose sole purpose is to make inspection and debugging easier.
27246 A list of @dfn{service extensions}, where each extension designates the
27247 target service type and a procedure that, given the parameters of the
27248 service, returns a list of objects to extend the service of that type.
27250 Every service type has at least one service extension. The only
27251 exception is the @dfn{boot service type}, which is the ultimate service.
27254 Optionally, a default value for instances of this type.
27257 In this example, @code{guix-service-type} extends three services:
27260 @item shepherd-root-service-type
27261 The @code{guix-shepherd-service} procedure defines how the Shepherd
27262 service is extended. Namely, it returns a @code{<shepherd-service>}
27263 object that defines how @command{guix-daemon} is started and stopped
27264 (@pxref{Shepherd Services}).
27266 @item account-service-type
27267 This extension for this service is computed by @code{guix-accounts},
27268 which returns a list of @code{user-group} and @code{user-account}
27269 objects representing the build user accounts (@pxref{Invoking
27272 @item activation-service-type
27273 Here @code{guix-activation} is a procedure that returns a gexp, which is
27274 a code snippet to run at ``activation time''---e.g., when the service is
27278 A service of this type is instantiated like this:
27281 (service guix-service-type
27282 (guix-configuration
27284 (use-substitutes? #f)))
27287 The second argument to the @code{service} form is a value representing
27288 the parameters of this specific service instance.
27289 @xref{guix-configuration-type, @code{guix-configuration}}, for
27290 information about the @code{guix-configuration} data type. When the
27291 value is omitted, the default value specified by
27292 @code{guix-service-type} is used:
27295 (service guix-service-type)
27298 @code{guix-service-type} is quite simple because it extends other
27299 services but is not extensible itself.
27301 @c @subsubsubsection Extensible Service Types
27303 The service type for an @emph{extensible} service looks like this:
27306 (define udev-service-type
27307 (service-type (name 'udev)
27309 (list (service-extension shepherd-root-service-type
27310 udev-shepherd-service)))
27312 (compose concatenate) ;concatenate the list of rules
27313 (extend (lambda (config rules)
27315 (($ <udev-configuration> udev initial-rules)
27316 (udev-configuration
27317 (udev udev) ;the udev package to use
27318 (rules (append initial-rules rules)))))))))
27321 This is the service type for the
27322 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
27323 management daemon}. Compared to the previous example, in addition to an
27324 extension of @code{shepherd-root-service-type}, we see two new fields:
27328 This is the procedure to @dfn{compose} the list of extensions to
27329 services of this type.
27331 Services can extend the udev service by passing it lists of rules; we
27332 compose those extensions simply by concatenating them.
27335 This procedure defines how the value of the service is @dfn{extended} with
27336 the composition of the extensions.
27338 Udev extensions are composed into a list of rules, but the udev service
27339 value is itself a @code{<udev-configuration>} record. So here, we
27340 extend that record by appending the list of rules it contains to the
27341 list of contributed rules.
27344 This is a string giving an overview of the service type. The string can
27345 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
27346 @command{guix system search} command searches these strings and displays
27347 them (@pxref{Invoking guix system}).
27350 There can be only one instance of an extensible service type such as
27351 @code{udev-service-type}. If there were more, the
27352 @code{service-extension} specifications would be ambiguous.
27354 Still here? The next section provides a reference of the programming
27355 interface for services.
27357 @node Service Reference
27358 @subsection Service Reference
27360 We have seen an overview of service types (@pxref{Service Types and
27361 Services}). This section provides a reference on how to manipulate
27362 services and service types. This interface is provided by the
27363 @code{(gnu services)} module.
27365 @deffn {Scheme Procedure} service @var{type} [@var{value}]
27366 Return a new service of @var{type}, a @code{<service-type>} object (see
27367 below.) @var{value} can be any object; it represents the parameters of
27368 this particular service instance.
27370 When @var{value} is omitted, the default value specified by @var{type}
27371 is used; if @var{type} does not specify a default value, an error is
27374 For instance, this:
27377 (service openssh-service-type)
27381 is equivalent to this:
27384 (service openssh-service-type
27385 (openssh-configuration))
27388 In both cases the result is an instance of @code{openssh-service-type}
27389 with the default configuration.
27392 @deffn {Scheme Procedure} service? @var{obj}
27393 Return true if @var{obj} is a service.
27396 @deffn {Scheme Procedure} service-kind @var{service}
27397 Return the type of @var{service}---i.e., a @code{<service-type>} object.
27400 @deffn {Scheme Procedure} service-value @var{service}
27401 Return the value associated with @var{service}. It represents its
27405 Here is an example of how a service is created and manipulated:
27409 (service nginx-service-type
27410 (nginx-configuration
27412 (log-directory log-directory)
27413 (run-directory run-directory)
27414 (file config-file))))
27419 (eq? (service-kind s) nginx-service-type)
27423 The @code{modify-services} form provides a handy way to change the
27424 parameters of some of the services of a list such as
27425 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
27426 evaluates to a list of services. Of course, you could always use
27427 standard list combinators such as @code{map} and @code{fold} to do that
27428 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
27429 @code{modify-services} simply provides a more concise form for this
27432 @deffn {Scheme Syntax} modify-services @var{services} @
27433 (@var{type} @var{variable} => @var{body}) @dots{}
27435 Modify the services listed in @var{services} according to the given
27436 clauses. Each clause has the form:
27439 (@var{type} @var{variable} => @var{body})
27442 where @var{type} is a service type---e.g.,
27443 @code{guix-service-type}---and @var{variable} is an identifier that is
27444 bound within the @var{body} to the service parameters---e.g., a
27445 @code{guix-configuration} instance---of the original service of that
27448 The @var{body} should evaluate to the new service parameters, which will
27449 be used to configure the new service. This new service will replace the
27450 original in the resulting list. Because a service's service parameters
27451 are created using @code{define-record-type*}, you can write a succinct
27452 @var{body} that evaluates to the new service parameters by using the
27453 @code{inherit} feature that @code{define-record-type*} provides.
27455 @xref{Using the Configuration System}, for example usage.
27459 Next comes the programming interface for service types. This is
27460 something you want to know when writing new service definitions, but not
27461 necessarily when simply looking for ways to customize your
27462 @code{operating-system} declaration.
27464 @deftp {Data Type} service-type
27465 @cindex service type
27466 This is the representation of a @dfn{service type} (@pxref{Service Types
27471 This is a symbol, used only to simplify inspection and debugging.
27473 @item @code{extensions}
27474 A non-empty list of @code{<service-extension>} objects (see below).
27476 @item @code{compose} (default: @code{#f})
27477 If this is @code{#f}, then the service type denotes services that cannot
27478 be extended---i.e., services that do not receive ``values'' from other
27481 Otherwise, it must be a one-argument procedure. The procedure is called
27482 by @code{fold-services} and is passed a list of values collected from
27483 extensions. It may return any single value.
27485 @item @code{extend} (default: @code{#f})
27486 If this is @code{#f}, services of this type cannot be extended.
27488 Otherwise, it must be a two-argument procedure: @code{fold-services}
27489 calls it, passing it the initial value of the service as the first
27490 argument and the result of applying @code{compose} to the extension
27491 values as the second argument. It must return a value that is a valid
27492 parameter value for the service instance.
27495 @xref{Service Types and Services}, for examples.
27498 @deffn {Scheme Procedure} service-extension @var{target-type} @
27500 Return a new extension for services of type @var{target-type}.
27501 @var{compute} must be a one-argument procedure: @code{fold-services}
27502 calls it, passing it the value associated with the service that provides
27503 the extension; it must return a valid value for the target service.
27506 @deffn {Scheme Procedure} service-extension? @var{obj}
27507 Return true if @var{obj} is a service extension.
27510 Occasionally, you might want to simply extend an existing service. This
27511 involves creating a new service type and specifying the extension of
27512 interest, which can be verbose; the @code{simple-service} procedure
27513 provides a shorthand for this.
27515 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
27516 Return a service that extends @var{target} with @var{value}. This works
27517 by creating a singleton service type @var{name}, of which the returned
27518 service is an instance.
27520 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
27524 (simple-service 'my-mcron-job mcron-service-type
27525 #~(job '(next-hour (3)) "guix gc -F 2G"))
27529 At the core of the service abstraction lies the @code{fold-services}
27530 procedure, which is responsible for ``compiling'' a list of services
27531 down to a single directory that contains everything needed to boot and
27532 run the system---the directory shown by the @command{guix system build}
27533 command (@pxref{Invoking guix system}). In essence, it propagates
27534 service extensions down the service graph, updating each node parameters
27535 on the way, until it reaches the root node.
27537 @deffn {Scheme Procedure} fold-services @var{services} @
27538 [#:target-type @var{system-service-type}]
27539 Fold @var{services} by propagating their extensions down to the root of
27540 type @var{target-type}; return the root service adjusted accordingly.
27543 Lastly, the @code{(gnu services)} module also defines several essential
27544 service types, some of which are listed below.
27546 @defvr {Scheme Variable} system-service-type
27547 This is the root of the service graph. It produces the system directory
27548 as returned by the @command{guix system build} command.
27551 @defvr {Scheme Variable} boot-service-type
27552 The type of the ``boot service'', which produces the @dfn{boot script}.
27553 The boot script is what the initial RAM disk runs when booting.
27556 @defvr {Scheme Variable} etc-service-type
27557 The type of the @file{/etc} service. This service is used to create
27558 files under @file{/etc} and can be extended by
27559 passing it name/file tuples such as:
27562 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
27565 In this example, the effect would be to add an @file{/etc/issue} file
27566 pointing to the given file.
27569 @defvr {Scheme Variable} setuid-program-service-type
27570 Type for the ``setuid-program service''. This service collects lists of
27571 executable file names, passed as gexps, and adds them to the set of
27572 setuid-root programs on the system (@pxref{Setuid Programs}).
27575 @defvr {Scheme Variable} profile-service-type
27576 Type of the service that populates the @dfn{system profile}---i.e., the
27577 programs under @file{/run/current-system/profile}. Other services can
27578 extend it by passing it lists of packages to add to the system profile.
27581 @cindex provenance tracking, of the operating system
27582 @defvr {Scheme Variable} provenance-service-type
27583 This is the type of the service that records @dfn{provenance meta-data}
27584 in the system itself. It creates several files under
27585 @file{/run/current-system}:
27589 This is a ``channel file'' that can be passed to @command{guix pull -C}
27590 or @command{guix time-machine -C}, and which describes the channels used
27591 to build the system, if that information was available
27592 (@pxref{Channels}).
27594 @item configuration.scm
27595 This is the file that was passed as the value for this
27596 @code{provenance-service-type} service. By default, @command{guix
27597 system reconfigure} automatically passes the OS configuration file it
27598 received on the command line.
27601 This contains the same information as the two other files but in a
27602 format that is more readily processable.
27605 In general, these two pieces of information (channels and configuration
27606 file) are enough to reproduce the operating system ``from source''.
27609 This information is necessary to rebuild your operating system, but it
27610 is not always sufficient. In particular, @file{configuration.scm}
27611 itself is insufficient if it is not self-contained---if it refers to
27612 external Guile modules or to extra files. If you want
27613 @file{configuration.scm} to be self-contained, we recommend that modules
27614 or files it refers to be part of a channel.
27616 Besides, provenance meta-data is ``silent'' in the sense that it does
27617 not change the bits contained in your system, @emph{except for the
27618 meta-data bits themselves}. Two different OS configurations or sets of
27619 channels can lead to the same system, bit-for-bit; when
27620 @code{provenance-service-type} is used, these two systems will have
27621 different meta-data and thus different store file names, which makes
27622 comparison less trivial.
27625 This service is automatically added to your operating system
27626 configuration when you use @command{guix system reconfigure},
27627 @command{guix system init}, or @command{guix deploy}.
27630 @node Shepherd Services
27631 @subsection Shepherd Services
27633 @cindex shepherd services
27635 @cindex init system
27636 The @code{(gnu services shepherd)} module provides a way to define
27637 services managed by the GNU@tie{}Shepherd, which is the
27638 initialization system---the first process that is started when the
27639 system boots, also known as PID@tie{}1
27640 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
27642 Services in the Shepherd can depend on each other. For instance, the
27643 SSH daemon may need to be started after the syslog daemon has been
27644 started, which in turn can only happen once all the file systems have
27645 been mounted. The simple operating system defined earlier (@pxref{Using
27646 the Configuration System}) results in a service graph like this:
27648 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
27650 You can actually generate such a graph for any operating system
27651 definition using the @command{guix system shepherd-graph} command
27652 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
27654 The @code{%shepherd-root-service} is a service object representing
27655 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
27656 by passing it lists of @code{<shepherd-service>} objects.
27658 @deftp {Data Type} shepherd-service
27659 The data type representing a service managed by the Shepherd.
27662 @item @code{provision}
27663 This is a list of symbols denoting what the service provides.
27665 These are the names that may be passed to @command{herd start},
27666 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
27667 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
27668 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
27670 @item @code{requirement} (default: @code{'()})
27671 List of symbols denoting the Shepherd services this one depends on.
27673 @cindex one-shot services, for the Shepherd
27674 @item @code{one-shot?} (default: @code{#f})
27675 Whether this service is @dfn{one-shot}. One-shot services stop immediately
27676 after their @code{start} action has completed. @xref{Slots of services,,,
27677 shepherd, The GNU Shepherd Manual}, for more info.
27679 @item @code{respawn?} (default: @code{#t})
27680 Whether to restart the service when it stops, for instance when the
27681 underlying process dies.
27684 @itemx @code{stop} (default: @code{#~(const #f)})
27685 The @code{start} and @code{stop} fields refer to the Shepherd's
27686 facilities to start and stop processes (@pxref{Service De- and
27687 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
27688 G-expressions that get expanded in the Shepherd configuration file
27689 (@pxref{G-Expressions}).
27691 @item @code{actions} (default: @code{'()})
27692 @cindex actions, of Shepherd services
27693 This is a list of @code{shepherd-action} objects (see below) defining
27694 @dfn{actions} supported by the service, in addition to the standard
27695 @code{start} and @code{stop} actions. Actions listed here become available as
27696 @command{herd} sub-commands:
27699 herd @var{action} @var{service} [@var{arguments}@dots{}]
27702 @item @code{auto-start?} (default: @code{#t})
27703 Whether this service should be started automatically by the Shepherd. If it
27704 is @code{#f} the service has to be started manually with @code{herd start}.
27706 @item @code{documentation}
27707 A documentation string, as shown when running:
27710 herd doc @var{service-name}
27713 where @var{service-name} is one of the symbols in @code{provision}
27714 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
27716 @item @code{modules} (default: @code{%default-modules})
27717 This is the list of modules that must be in scope when @code{start} and
27718 @code{stop} are evaluated.
27723 @deftp {Data Type} shepherd-action
27724 This is the data type that defines additional actions implemented by a
27725 Shepherd service (see above).
27729 Symbol naming the action.
27731 @item documentation
27732 This is a documentation string for the action. It can be viewed by running:
27735 herd doc @var{service} action @var{action}
27739 This should be a gexp that evaluates to a procedure of at least one argument,
27740 which is the ``running value'' of the service (@pxref{Slots of services,,,
27741 shepherd, The GNU Shepherd Manual}).
27744 The following example defines an action called @code{say-hello} that kindly
27750 (documentation "Say hi!")
27751 (procedure #~(lambda (running . args)
27752 (format #t "Hello, friend! arguments: ~s\n"
27757 Assuming this action is added to the @code{example} service, then you can do:
27760 # herd say-hello example
27761 Hello, friend! arguments: ()
27762 # herd say-hello example a b c
27763 Hello, friend! arguments: ("a" "b" "c")
27766 This, as you can see, is a fairly sophisticated way to say hello.
27767 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
27771 @defvr {Scheme Variable} shepherd-root-service-type
27772 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
27774 This is the service type that extensions target when they want to create
27775 shepherd services (@pxref{Service Types and Services}, for an example).
27776 Each extension must pass a list of @code{<shepherd-service>}.
27779 @defvr {Scheme Variable} %shepherd-root-service
27780 This service represents PID@tie{}1.
27784 @node Documentation
27785 @chapter Documentation
27787 @cindex documentation, searching for
27788 @cindex searching for documentation
27789 @cindex Info, documentation format
27791 @cindex manual pages
27792 In most cases packages installed with Guix come with documentation.
27793 There are two main documentation formats: ``Info'', a browseable
27794 hypertext format used for GNU software, and ``manual pages'' (or ``man
27795 pages''), the linear documentation format traditionally found on Unix.
27796 Info manuals are accessed with the @command{info} command or with Emacs,
27797 and man pages are accessed using @command{man}.
27799 You can look for documentation of software installed on your system by
27800 keyword. For example, the following command searches for information
27801 about ``TLS'' in Info manuals:
27805 "(emacs)Network Security" -- STARTTLS
27806 "(emacs)Network Security" -- TLS
27807 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
27808 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
27813 The command below searches for the same keyword in man pages:
27817 SSL (7) - OpenSSL SSL/TLS library
27818 certtool (1) - GnuTLS certificate tool
27822 These searches are purely local to your computer so you have the
27823 guarantee that documentation you find corresponds to what you have
27824 actually installed, you can access it off-line, and your privacy is
27827 Once you have these results, you can view the relevant documentation by
27831 $ info "(gnutls)Core TLS API"
27841 Info manuals contain sections and indices as well as hyperlinks like
27842 those found in Web pages. The @command{info} reader (@pxref{Top, Info
27843 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
27844 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
27845 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
27846 Introduction}, for an introduction to Info navigation.
27848 @node Installing Debugging Files
27849 @chapter Installing Debugging Files
27851 @cindex debugging files
27852 Program binaries, as produced by the GCC compilers for instance, are
27853 typically written in the ELF format, with a section containing
27854 @dfn{debugging information}. Debugging information is what allows the
27855 debugger, GDB, to map binary code to source code; it is required to
27856 debug a compiled program in good conditions.
27858 The problem with debugging information is that is takes up a fair amount
27859 of disk space. For example, debugging information for the GNU C Library
27860 weighs in at more than 60 MiB. Thus, as a user, keeping all the
27861 debugging info of all the installed programs is usually not an option.
27862 Yet, space savings should not come at the cost of an impediment to
27863 debugging---especially in the GNU system, which should make it easier
27864 for users to exert their computing freedom (@pxref{GNU Distribution}).
27866 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
27867 mechanism that allows users to get the best of both worlds: debugging
27868 information can be stripped from the binaries and stored in separate
27869 files. GDB is then able to load debugging information from those files,
27870 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
27873 The GNU distribution takes advantage of this by storing debugging
27874 information in the @code{lib/debug} sub-directory of a separate package
27875 output unimaginatively called @code{debug} (@pxref{Packages with
27876 Multiple Outputs}). Users can choose to install the @code{debug} output
27877 of a package when they need it. For instance, the following command
27878 installs the debugging information for the GNU C Library and for GNU
27882 guix install glibc:debug guile:debug
27885 GDB must then be told to look for debug files in the user's profile, by
27886 setting the @code{debug-file-directory} variable (consider setting it
27887 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
27891 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
27894 From there on, GDB will pick up debugging information from the
27895 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
27897 In addition, you will most likely want GDB to be able to show the source
27898 code being debugged. To do that, you will have to unpack the source
27899 code of the package of interest (obtained with @code{guix build
27900 --source}, @pxref{Invoking guix build}), and to point GDB to that source
27901 directory using the @code{directory} command (@pxref{Source Path,
27902 @code{directory},, gdb, Debugging with GDB}).
27904 @c XXX: keep me up-to-date
27905 The @code{debug} output mechanism in Guix is implemented by the
27906 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
27907 opt-in---debugging information is available only for the packages
27908 with definitions explicitly declaring a @code{debug} output. This may be
27909 changed to opt-out in the future if our build farm servers can handle
27910 the load. To check whether a package has a @code{debug} output, use
27911 @command{guix package --list-available} (@pxref{Invoking guix package}).
27914 @node Security Updates
27915 @chapter Security Updates
27917 @cindex security updates
27918 @cindex security vulnerabilities
27919 Occasionally, important security vulnerabilities are discovered in software
27920 packages and must be patched. Guix developers try hard to keep track of
27921 known vulnerabilities and to apply fixes as soon as possible in the
27922 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
27923 containing only security updates.) The @command{guix lint} tool helps
27924 developers find out about vulnerable versions of software packages in the
27929 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
27930 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
27931 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
27935 @xref{Invoking guix lint}, for more information.
27937 Guix follows a functional
27938 package management discipline (@pxref{Introduction}), which implies
27939 that, when a package is changed, @emph{every package that depends on it}
27940 must be rebuilt. This can significantly slow down the deployment of
27941 fixes in core packages such as libc or Bash, since basically the whole
27942 distribution would need to be rebuilt. Using pre-built binaries helps
27943 (@pxref{Substitutes}), but deployment may still take more time than
27947 To address this, Guix implements @dfn{grafts}, a mechanism that allows
27948 for fast deployment of critical updates without the costs associated
27949 with a whole-distribution rebuild. The idea is to rebuild only the
27950 package that needs to be patched, and then to ``graft'' it onto packages
27951 explicitly installed by the user and that were previously referring to
27952 the original package. The cost of grafting is typically very low, and
27953 order of magnitudes lower than a full rebuild of the dependency chain.
27955 @cindex replacements of packages, for grafts
27956 For instance, suppose a security update needs to be applied to Bash.
27957 Guix developers will provide a package definition for the ``fixed''
27958 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
27959 Packages}). Then, the original package definition is augmented with a
27960 @code{replacement} field pointing to the package containing the bug fix:
27967 (replacement bash-fixed)))
27970 From there on, any package depending directly or indirectly on Bash---as
27971 reported by @command{guix gc --requisites} (@pxref{Invoking guix
27972 gc})---that is installed is automatically ``rewritten'' to refer to
27973 @code{bash-fixed} instead of @code{bash}. This grafting process takes
27974 time proportional to the size of the package, usually less than a
27975 minute for an ``average'' package on a recent machine. Grafting is
27976 recursive: when an indirect dependency requires grafting, then grafting
27977 ``propagates'' up to the package that the user is installing.
27979 Currently, the length of the name and version of the graft and that of
27980 the package it replaces (@code{bash-fixed} and @code{bash} in the example
27981 above) must be equal. This restriction mostly comes from the fact that
27982 grafting works by patching files, including binary files, directly.
27983 Other restrictions may apply: for instance, when adding a graft to a
27984 package providing a shared library, the original shared library and its
27985 replacement must have the same @code{SONAME} and be binary-compatible.
27987 The @option{--no-grafts} command-line option allows you to forcefully
27988 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
27992 guix build bash --no-grafts
27996 returns the store file name of the original Bash, whereas:
28003 returns the store file name of the ``fixed'', replacement Bash. This
28004 allows you to distinguish between the two variants of Bash.
28006 To verify which Bash your whole profile refers to, you can run
28007 (@pxref{Invoking guix gc}):
28010 guix gc -R `readlink -f ~/.guix-profile` | grep bash
28014 @dots{} and compare the store file names that you get with those above.
28015 Likewise for a complete Guix system generation:
28018 guix gc -R `guix system build my-config.scm` | grep bash
28021 Lastly, to check which Bash running processes are using, you can use the
28022 @command{lsof} command:
28025 lsof | grep /gnu/store/.*bash
28029 @node Bootstrapping
28030 @chapter Bootstrapping
28032 @c Adapted from the ELS 2013 paper.
28034 @cindex bootstrapping
28036 Bootstrapping in our context refers to how the distribution gets built
28037 ``from nothing''. Remember that the build environment of a derivation
28038 contains nothing but its declared inputs (@pxref{Introduction}). So
28039 there's an obvious chicken-and-egg problem: how does the first package
28040 get built? How does the first compiler get compiled? Note that this is
28041 a question of interest only to the curious hacker, not to the regular
28042 user, so you can shamelessly skip this section if you consider yourself
28043 a ``regular user''.
28045 @cindex bootstrap binaries
28046 The GNU system is primarily made of C code, with libc at its core. The
28047 GNU build system itself assumes the availability of a Bourne shell and
28048 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
28049 `grep'. Furthermore, build programs---programs that run
28050 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
28051 (@pxref{Derivations}). Consequently, to be able to build anything at
28052 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
28053 Binutils, libc, and the other packages mentioned above---the
28054 @dfn{bootstrap binaries}.
28056 These bootstrap binaries are ``taken for granted'', though we can also
28057 re-create them if needed (more on that later).
28059 For @code{i686-linux} and @code{x86_64-linux} the Guix bootstrap process is
28060 more elaborate, @pxref{Reduced Binary Seed Bootstrap}.
28063 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
28064 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
28067 @node Reduced Binary Seed Bootstrap
28068 @section The Reduced Binary Seed Bootstrap
28070 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
28071 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
28072 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
28073 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
28074 ``taken for granted.''
28076 Taking these binaries for granted means that we consider them to be a correct
28077 and trustworthy `seed' for building the complete system. Therein lies a
28078 problem: the current combined size of these bootstrap binaries is about 250MB
28079 (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing or even inspecting
28080 these is next to impossible.
28082 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a ``Reduced
28083 Binary Seed'' bootstrap @footnote{We would like to say: ``Full Source
28084 Bootstrap'' and while we are working towards that goal it would be hyperbole
28085 to use that term for what we do now.}.
28087 The Reduced Binary Seed bootstrap removes the most critical tools---from a
28088 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
28089 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
28090 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
28091 written in Scheme and the Mes C Library, built for TinyCC and for GCC). Using
28092 these new binary seeds and a new set of
28094 packages@footnote{@c
28109 gcc-mesboot1-wrapper,
28110 glibc-headers-mesboot,
28114 gcc-mesboot-wrapper.
28117 the ``missing'' Binutils, GCC, and the GNU C Library are built from source.
28118 From here on the more traditional bootstrap process resumes. This approach
28119 has reduced the bootstrap binaries in size to about 130MB. Work is ongoing to
28120 reduce this further. If you are interested, join us on @code{#bootstrappable}
28121 on the Freenode IRC network.
28123 @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
28124 @c dot -T png doc/images/gcc-mesboot-bag-graph.dot > doc/images/gcc-mesboot-bag-graph.png
28126 Below is the generated dependency graph for @code{gcc-mesboot}, the bootstrap
28127 compiler used to build the rest of GuixSD.
28129 @image{images/gcc-mesboot-bag-graph,6in,,Dependency graph of the gcc-mesboot}
28131 @node Preparing to Use the Bootstrap Binaries
28132 @section Preparing to Use the Bootstrap Binaries
28134 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
28135 @c large image, it's hard to scroll. Oh well.
28136 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
28138 The figure above shows the very beginning of the dependency graph of the
28139 distribution, corresponding to the package definitions of the @code{(gnu
28140 packages bootstrap)} module. A similar figure can be generated with
28141 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
28144 guix graph -t derivation \
28145 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
28146 | dot -Tps > gcc.ps
28149 or, for the Reduced Binary Seed bootstrap
28152 guix graph -t derivation \
28153 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
28154 | dot -Tps > mes.ps
28157 At this level of detail, things are
28158 slightly complex. First, Guile itself consists of an ELF executable,
28159 along with many source and compiled Scheme files that are dynamically
28160 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
28161 tarball shown in this graph. This tarball is part of Guix's ``source''
28162 distribution, and gets inserted into the store with @code{add-to-store}
28163 (@pxref{The Store}).
28165 But how do we write a derivation that unpacks this tarball and adds it
28166 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
28167 derivation---the first one that gets built---uses @code{bash} as its
28168 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
28169 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
28170 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
28171 the Guix source distribution, whose sole purpose is to allow the Guile
28172 tarball to be unpacked.
28174 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
28175 Guile that can be used to run subsequent build programs. Its first task
28176 is to download tarballs containing the other pre-built binaries---this
28177 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
28178 @code{ftp-client.scm} are used for this purpose. The
28179 @code{module-import.drv} derivations import those modules in a directory
28180 in the store, using the original layout. The
28181 @code{module-import-compiled.drv} derivations compile those modules, and
28182 write them in an output directory with the right layout. This
28183 corresponds to the @code{#:modules} argument of
28184 @code{build-expression->derivation} (@pxref{Derivations}).
28186 Finally, the various tarballs are unpacked by the derivations
28187 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
28188 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
28189 point we have a working C tool chain.
28191 @unnumberedsec Building the Build Tools
28193 Bootstrapping is complete when we have a full tool chain that does not
28194 depend on the pre-built bootstrap tools discussed above. This
28195 no-dependency requirement is verified by checking whether the files of
28196 the final tool chain contain references to the @file{/gnu/store}
28197 directories of the bootstrap inputs. The process that leads to this
28198 ``final'' tool chain is described by the package definitions found in
28199 the @code{(gnu packages commencement)} module.
28201 The @command{guix graph} command allows us to ``zoom out'' compared to
28202 the graph above, by looking at the level of package objects instead of
28203 individual derivations---remember that a package may translate to
28204 several derivations, typically one derivation to download its source,
28205 one to build the Guile modules it needs, and one to actually build the
28206 package from source. The command:
28209 guix graph -t bag \
28210 -e '(@@@@ (gnu packages commencement)
28211 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
28215 produces the dependency graph leading to the ``final'' C
28216 library@footnote{You may notice the @code{glibc-intermediate} label,
28217 suggesting that it is not @emph{quite} final, but as a good
28218 approximation, we will consider it final.}, depicted below.
28220 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
28222 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
28223 The first tool that gets built with the bootstrap binaries is
28224 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
28225 for all the following packages. From there Findutils and Diffutils get
28228 Then come the first-stage Binutils and GCC, built as pseudo cross
28229 tools---i.e., with @code{--target} equal to @code{--host}. They are
28230 used to build libc. Thanks to this cross-build trick, this libc is
28231 guaranteed not to hold any reference to the initial tool chain.
28233 From there the final Binutils and GCC (not shown above) are built.
28235 from the final Binutils, and links programs against the just-built libc.
28236 This tool chain is used to build the other packages used by Guix and by
28237 the GNU Build System: Guile, Bash, Coreutils, etc.
28239 And voilà! At this point we have the complete set of build tools that
28240 the GNU Build System expects. These are in the @code{%final-inputs}
28241 variable of the @code{(gnu packages commencement)} module, and are
28242 implicitly used by any package that uses @code{gnu-build-system}
28243 (@pxref{Build Systems, @code{gnu-build-system}}).
28246 @unnumberedsec Building the Bootstrap Binaries
28248 @cindex bootstrap binaries
28249 Because the final tool chain does not depend on the bootstrap binaries,
28250 those rarely need to be updated. Nevertheless, it is useful to have an
28251 automated way to produce them, should an update occur, and this is what
28252 the @code{(gnu packages make-bootstrap)} module provides.
28254 The following command builds the tarballs containing the bootstrap binaries
28255 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
28256 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
28257 and Guile, and a tarball containing a mixture of Coreutils and other basic
28258 command-line tools):
28261 guix build bootstrap-tarballs
28264 The generated tarballs are those that should be referred to in the
28265 @code{(gnu packages bootstrap)} module mentioned at the beginning of
28268 Still here? Then perhaps by now you've started to wonder: when do we
28269 reach a fixed point? That is an interesting question! The answer is
28270 unknown, but if you would like to investigate further (and have
28271 significant computational and storage resources to do so), then let us
28274 @unnumberedsec Reducing the Set of Bootstrap Binaries
28276 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
28277 binary code! Why is that a problem? It's a problem because these big chunks
28278 of binary code are practically non-auditable, which makes it hard to establish
28279 what source code produced them. Every unauditable binary also leaves us
28280 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
28281 paper @emph{Reflections on Trusting Trust}.
28283 This is mitigated by the fact that our bootstrap binaries were generated
28284 from an earlier Guix revision. Nevertheless it lacks the level of
28285 transparency that we get in the rest of the package dependency graph,
28286 where Guix always gives us a source-to-binary mapping. Thus, our goal
28287 is to reduce the set of bootstrap binaries to the bare minimum.
28289 The @uref{http://bootstrappable.org, Bootstrappable.org web site} lists
28290 on-going projects to do that. One of these is about replacing the
28291 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
28292 of increasing complexity, which could be built from source starting from
28293 a simple and auditable assembler.
28295 Our first major achievement is the replacement of of GCC, the GNU C Library
28296 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
28297 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
28298 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
28299 bootstrapped yet and thus we inject them as binary seeds. We call this the
28300 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
28301 binaries! Also, it has eliminated the C compiler binary; i686-linux and
28302 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
28304 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
28305 also looking at any other bootstrap binaries. Your help is welcome!
28308 @chapter Porting to a New Platform
28310 As discussed above, the GNU distribution is self-contained, and
28311 self-containment is achieved by relying on pre-built ``bootstrap
28312 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
28313 operating system kernel, CPU architecture, and application binary
28314 interface (ABI). Thus, to port the distribution to a platform that is
28315 not yet supported, one must build those bootstrap binaries, and update
28316 the @code{(gnu packages bootstrap)} module to use them on that platform.
28318 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
28319 When everything goes well, and assuming the GNU tool chain supports the
28320 target platform, this can be as simple as running a command like this
28324 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
28327 For this to work, the @code{glibc-dynamic-linker} procedure in
28328 @code{(gnu packages bootstrap)} must be augmented to return the right
28329 file name for libc's dynamic linker on that platform; likewise,
28330 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
28331 taught about the new platform.
28333 Once these are built, the @code{(gnu packages bootstrap)} module needs
28334 to be updated to refer to these binaries on the target platform. That
28335 is, the hashes and URLs of the bootstrap tarballs for the new platform
28336 must be added alongside those of the currently supported platforms. The
28337 bootstrap Guile tarball is treated specially: it is expected to be
28338 available locally, and @file{gnu/local.mk} has rules to download it for
28339 the supported architectures; a rule for the new platform must be added
28342 In practice, there may be some complications. First, it may be that the
28343 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
28344 above) is not recognized by all the GNU tools. Typically, glibc
28345 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
28346 configure flag (see @code{gcc.scm} for examples of how to handle this).
28347 Second, some of the required packages could fail to build for that
28348 platform. Lastly, the generated binaries could be broken for some
28351 @c *********************************************************************
28352 @include contributing.texi
28354 @c *********************************************************************
28355 @node Acknowledgments
28356 @chapter Acknowledgments
28358 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
28359 which was designed and
28360 implemented by Eelco Dolstra, with contributions from other people (see
28361 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
28362 management, and promoted unprecedented features, such as transactional
28363 package upgrades and rollbacks, per-user profiles, and referentially
28364 transparent build processes. Without this work, Guix would not exist.
28366 The Nix-based software distributions, Nixpkgs and NixOS, have also been
28367 an inspiration for Guix.
28369 GNU@tie{}Guix itself is a collective work with contributions from a
28370 number of people. See the @file{AUTHORS} file in Guix for more
28371 information on these fine people. The @file{THANKS} file lists people
28372 who have helped by reporting bugs, taking care of the infrastructure,
28373 providing artwork and themes, making suggestions, and more---thank you!
28376 @c *********************************************************************
28377 @node GNU Free Documentation License
28378 @appendix GNU Free Documentation License
28379 @cindex license, GNU Free Documentation License
28380 @include fdl-1.3.texi
28382 @c *********************************************************************
28383 @node Concept Index
28384 @unnumbered Concept Index
28387 @node Programming Index
28388 @unnumbered Programming Index
28389 @syncodeindex tp fn
28390 @syncodeindex vr fn
28395 @c Local Variables:
28396 @c ispell-local-dictionary: "american";