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@*
77 Copyright @copyright{} 2020 Jack Hill@*
79 Permission is granted to copy, distribute and/or modify this document
80 under the terms of the GNU Free Documentation License, Version 1.3 or
81 any later version published by the Free Software Foundation; with no
82 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
83 copy of the license is included in the section entitled ``GNU Free
84 Documentation License''.
87 @dircategory System administration
89 * Guix: (guix). Manage installed software and system configuration.
90 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
91 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
92 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
93 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
94 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
97 @dircategory Software development
99 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
100 * guix build: (guix)Invoking guix build. Building packages.
101 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
105 @title GNU Guix Reference Manual
106 @subtitle Using the GNU Guix Functional Package Manager
107 @author The GNU Guix Developers
110 @vskip 0pt plus 1filll
111 Edition @value{EDITION} @*
119 @c *********************************************************************
123 This document describes GNU Guix version @value{VERSION}, a functional
124 package management tool written for the GNU system.
126 @c TRANSLATORS: You can replace the following paragraph with information on
127 @c how to join your own translation team and how to report issues with the
129 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
130 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
131 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
132 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
133 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
134 would like to translate it in your native language, consider joining the
135 @uref{https://translationproject.org/domain/guix-manual.html, Translation
139 * Introduction:: What is Guix about?
140 * Installation:: Installing Guix.
141 * System Installation:: Installing the whole operating system.
142 * Package Management:: Package installation, upgrade, etc.
143 * Development:: Guix-aided software development.
144 * Programming Interface:: Using Guix in Scheme.
145 * Utilities:: Package management commands.
146 * System Configuration:: Configuring the operating system.
147 * Documentation:: Browsing software user manuals.
148 * Installing Debugging Files:: Feeding the debugger.
149 * Security Updates:: Deploying security fixes quickly.
150 * Bootstrapping:: GNU/Linux built from scratch.
151 * Porting:: Targeting another platform or kernel.
152 * Contributing:: Your help needed!
154 * Acknowledgments:: Thanks!
155 * GNU Free Documentation License:: The license of this manual.
156 * Concept Index:: Concepts.
157 * Programming Index:: Data types, functions, and variables.
160 --- The Detailed Node Listing ---
164 * Managing Software the Guix Way:: What's special.
165 * GNU Distribution:: The packages and tools.
169 * Binary Installation:: Getting Guix running in no time!
170 * Requirements:: Software needed to build and run Guix.
171 * Running the Test Suite:: Testing Guix.
172 * Setting Up the Daemon:: Preparing the build daemon's environment.
173 * Invoking guix-daemon:: Running the build daemon.
174 * Application Setup:: Application-specific setup.
176 Setting Up the Daemon
178 * Build Environment Setup:: Preparing the isolated build environment.
179 * Daemon Offload Setup:: Offloading builds to remote machines.
180 * SELinux Support:: Using an SELinux policy for the daemon.
184 * Limitations:: What you can expect.
185 * Hardware Considerations:: Supported hardware.
186 * USB Stick and DVD Installation:: Preparing the installation medium.
187 * Preparing for Installation:: Networking, partitioning, etc.
188 * Guided Graphical Installation:: Easy graphical installation.
189 * Manual Installation:: Manual installation for wizards.
190 * After System Installation:: When installation succeeded.
191 * Installing Guix in a VM:: Guix System playground.
192 * Building the Installation Image:: How this comes to be.
196 * Keyboard Layout and Networking and Partitioning:: Initial setup.
197 * Proceeding with the Installation:: Installing.
201 * Features:: How Guix will make your life brighter.
202 * Invoking guix package:: Package installation, removal, etc.
203 * Substitutes:: Downloading pre-built binaries.
204 * Packages with Multiple Outputs:: Single source package, multiple outputs.
205 * Invoking guix gc:: Running the garbage collector.
206 * Invoking guix pull:: Fetching the latest Guix and distribution.
207 * Channels:: Customizing the package collection.
208 * Invoking guix time-machine:: Running an older revision of Guix.
209 * Inferiors:: Interacting with another revision of Guix.
210 * Invoking guix describe:: Display information about your Guix revision.
211 * Invoking guix archive:: Exporting and importing store files.
215 * Official Substitute Server:: One particular source of substitutes.
216 * Substitute Server Authorization:: How to enable or disable substitutes.
217 * Substitute Authentication:: How Guix verifies substitutes.
218 * Proxy Settings:: How to get substitutes via proxy.
219 * Substitution Failure:: What happens when substitution fails.
220 * On Trusting Binaries:: How can you trust that binary blob?
224 * Invoking guix environment:: Setting up development environments.
225 * Invoking guix pack:: Creating software bundles.
227 Programming Interface
229 * Package Modules:: Packages from the programmer's viewpoint.
230 * Defining Packages:: Defining new packages.
231 * Build Systems:: Specifying how packages are built.
232 * The Store:: Manipulating the package store.
233 * Derivations:: Low-level interface to package derivations.
234 * The Store Monad:: Purely functional interface to the store.
235 * G-Expressions:: Manipulating build expressions.
236 * Invoking guix repl:: Fiddling with Guix interactively.
240 * package Reference:: The package data type.
241 * origin Reference:: The origin data type.
245 * Invoking guix build:: Building packages from the command line.
246 * Invoking guix edit:: Editing package definitions.
247 * Invoking guix download:: Downloading a file and printing its hash.
248 * Invoking guix hash:: Computing the cryptographic hash of a file.
249 * Invoking guix import:: Importing package definitions.
250 * Invoking guix refresh:: Updating package definitions.
251 * Invoking guix lint:: Finding errors in package definitions.
252 * Invoking guix size:: Profiling disk usage.
253 * Invoking guix graph:: Visualizing the graph of packages.
254 * Invoking guix publish:: Sharing substitutes.
255 * Invoking guix challenge:: Challenging substitute servers.
256 * Invoking guix copy:: Copying to and from a remote store.
257 * Invoking guix container:: Process isolation.
258 * Invoking guix weather:: Assessing substitute availability.
259 * Invoking guix processes:: Listing client processes.
261 Invoking @command{guix build}
263 * Common Build Options:: Build options for most commands.
264 * Package Transformation Options:: Creating variants of packages.
265 * Additional Build Options:: Options specific to 'guix build'.
266 * Debugging Build Failures:: Real life packaging experience.
270 * Using the Configuration System:: Customizing your GNU system.
271 * operating-system Reference:: Detail of operating-system declarations.
272 * File Systems:: Configuring file system mounts.
273 * Mapped Devices:: Block device extra processing.
274 * User Accounts:: Specifying user accounts.
275 * Keyboard Layout:: How the system interprets key strokes.
276 * Locales:: Language and cultural convention settings.
277 * Services:: Specifying system services.
278 * Setuid Programs:: Programs running with root privileges.
279 * X.509 Certificates:: Authenticating HTTPS servers.
280 * Name Service Switch:: Configuring libc's name service switch.
281 * Initial RAM Disk:: Linux-Libre bootstrapping.
282 * Bootloader Configuration:: Configuring the boot loader.
283 * Invoking guix system:: Instantiating a system configuration.
284 * Invoking guix deploy:: Deploying a system configuration to a remote host.
285 * Running Guix in a VM:: How to run Guix System in a virtual machine.
286 * Defining Services:: Adding new service definitions.
290 * Base Services:: Essential system services.
291 * Scheduled Job Execution:: The mcron service.
292 * Log Rotation:: The rottlog service.
293 * Networking Services:: Network setup, SSH daemon, etc.
294 * X Window:: Graphical display.
295 * Printing Services:: Local and remote printer support.
296 * Desktop Services:: D-Bus and desktop services.
297 * Sound Services:: ALSA and Pulseaudio services.
298 * Database Services:: SQL databases, key-value stores, etc.
299 * Mail Services:: IMAP, POP3, SMTP, and all that.
300 * Messaging Services:: Messaging services.
301 * Telephony Services:: Telephony services.
302 * Monitoring Services:: Monitoring services.
303 * Kerberos Services:: Kerberos services.
304 * Web Services:: Web servers.
305 * Certificate Services:: TLS certificates via Let's Encrypt.
306 * DNS Services:: DNS daemons.
307 * VPN Services:: VPN daemons.
308 * Network File System:: NFS related services.
309 * Continuous Integration:: The Cuirass service.
310 * Power Management Services:: Extending battery life.
311 * Audio Services:: The MPD.
312 * Virtualization Services:: Virtualization services.
313 * Version Control Services:: Providing remote access to Git repositories.
314 * Game Services:: Game servers.
315 * PAM Mount Service:: Service to mount volumes when logging in.
316 * Linux Services:: Services tied to the Linux kernel.
317 * Miscellaneous Services:: Other services.
321 * Service Composition:: The model for composing services.
322 * Service Types and Services:: Types and services.
323 * Service Reference:: API reference.
324 * Shepherd Services:: A particular type of service.
329 @c *********************************************************************
331 @chapter Introduction
334 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
335 using the international phonetic alphabet (IPA).} is a package
336 management tool for and distribution of the GNU system.
337 Guix makes it easy for unprivileged
338 users to install, upgrade, or remove software packages, to roll back to a
339 previous package set, to build packages from source, and generally
340 assists with the creation and maintenance of software environments.
343 @cindex GuixSD, now Guix System
344 @cindex Guix System Distribution, now Guix System
345 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
346 complements the available tools without interference (@pxref{Installation}),
347 or you can use it as a standalone operating system distribution,
348 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
349 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
350 group everything under the ``Guix'' banner since, after all, Guix System is
351 readily available through the @command{guix system} command, even if you're
352 using a different distro underneath!}. @xref{GNU Distribution}.
355 * Managing Software the Guix Way:: What's special.
356 * GNU Distribution:: The packages and tools.
359 @node Managing Software the Guix Way
360 @section Managing Software the Guix Way
362 @cindex user interfaces
363 Guix provides a command-line package management interface
364 (@pxref{Package Management}), tools to help with software development
365 (@pxref{Development}), command-line utilities for more advanced usage,
366 (@pxref{Utilities}), as well as Scheme programming interfaces
367 (@pxref{Programming Interface}).
369 Its @dfn{build daemon} is responsible for building packages on behalf of
370 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
371 binaries from authorized sources (@pxref{Substitutes}).
373 @cindex extensibility of the distribution
374 @cindex customization, of packages
375 Guix includes package definitions for many GNU and non-GNU packages, all
376 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
377 user's computing freedom}. It is @emph{extensible}: users can write
378 their own package definitions (@pxref{Defining Packages}) and make them
379 available as independent package modules (@pxref{Package Modules}). It
380 is also @emph{customizable}: users can @emph{derive} specialized package
381 definitions from existing ones, including from the command line
382 (@pxref{Package Transformation Options}).
384 @cindex functional package management
386 Under the hood, Guix implements the @dfn{functional package management}
387 discipline pioneered by Nix (@pxref{Acknowledgments}).
388 In Guix, the package build and installation process is seen
389 as a @emph{function}, in the mathematical sense. That function takes inputs,
390 such as build scripts, a compiler, and libraries, and
391 returns an installed package. As a pure function, its result depends
392 solely on its inputs---for instance, it cannot refer to software or
393 scripts that were not explicitly passed as inputs. A build function
394 always produces the same result when passed a given set of inputs. It
395 cannot alter the environment of the running system in
396 any way; for instance, it cannot create, modify, or delete files outside
397 of its build and installation directories. This is achieved by running
398 build processes in isolated environments (or @dfn{containers}), where only their
399 explicit inputs are visible.
402 The result of package build functions is @dfn{cached} in the file
403 system, in a special directory called @dfn{the store} (@pxref{The
404 Store}). Each package is installed in a directory of its own in the
405 store---by default under @file{/gnu/store}. The directory name contains
406 a hash of all the inputs used to build that package; thus, changing an
407 input yields a different directory name.
409 This approach is the foundation for the salient features of Guix: support
410 for transactional package upgrade and rollback, per-user installation, and
411 garbage collection of packages (@pxref{Features}).
414 @node GNU Distribution
415 @section GNU Distribution
418 Guix comes with a distribution of the GNU system consisting entirely of
419 free software@footnote{The term ``free'' here refers to the
420 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
421 users of that software}.}. The
422 distribution can be installed on its own (@pxref{System Installation}),
423 but it is also possible to install Guix as a package manager on top of
424 an installed GNU/Linux system (@pxref{Installation}). When we need to
425 distinguish between the two, we refer to the standalone distribution as
428 The distribution provides core GNU packages such as GNU libc, GCC, and
429 Binutils, as well as many GNU and non-GNU applications. The complete
430 list of available packages can be browsed
431 @url{https://www.gnu.org/software/guix/packages,on-line} or by
432 running @command{guix package} (@pxref{Invoking guix package}):
435 guix package --list-available
438 Our goal is to provide a practical 100% free software distribution of
439 Linux-based and other variants of GNU, with a focus on the promotion and
440 tight integration of GNU components, and an emphasis on programs and
441 tools that help users exert that freedom.
443 Packages are currently available on the following platforms:
448 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel;
451 Intel 32-bit architecture (IA32), Linux-Libre kernel;
454 ARMv7-A architecture with hard float, Thumb-2 and NEON,
455 using the EABI hard-float application binary interface (ABI),
456 and Linux-Libre kernel.
459 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
462 little-endian 64-bit MIPS processors, specifically the Loongson series,
463 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
464 supported; in particular, the project's build farms no longer provide
465 substitutes for this architecture.
469 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
470 configuration and Guix takes care of instantiating the configuration in a
471 transactional, reproducible, and stateless fashion (@pxref{System
472 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
473 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
474 Manual}), the well-known GNU utilities and tool chain, as well as the
475 graphical environment or system services of your choice.
477 Guix System is available on all the above platforms except
478 @code{mips64el-linux}.
481 For information on porting to other architectures or kernels,
484 Building this distribution is a cooperative effort, and you are invited
485 to join! @xref{Contributing}, for information about how you can help.
488 @c *********************************************************************
490 @chapter Installation
492 @cindex installing Guix
495 We recommend the use of this
496 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
497 shell installer script} to install Guix on top of a running GNU/Linux system,
498 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
499 with the installation of the package manager, which can be done on top of a
500 running GNU/Linux system. If, instead, you want to install the complete GNU
501 operating system, @pxref{System Installation}.} The script automates the
502 download, installation, and initial configuration of Guix. It should be run
506 @cindex foreign distro
507 @cindex directories related to foreign distro
508 When installed on a foreign distro, GNU@tie{}Guix complements the available
509 tools without interference. Its data lives exclusively in two directories,
510 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
511 such as @file{/etc}, are left untouched.
513 Once installed, Guix can be updated by running @command{guix pull}
514 (@pxref{Invoking guix pull}).
516 If you prefer to perform the installation steps manually or want to tweak
517 them, you may find the following subsections useful. They describe the
518 software requirements of Guix, as well as how to install it manually and get
522 * Binary Installation:: Getting Guix running in no time!
523 * Requirements:: Software needed to build and run Guix.
524 * Running the Test Suite:: Testing Guix.
525 * Setting Up the Daemon:: Preparing the build daemon's environment.
526 * Invoking guix-daemon:: Running the build daemon.
527 * Application Setup:: Application-specific setup.
528 * Upgrading Guix:: Upgrading Guix and its build daemon.
531 @node Binary Installation
532 @section Binary Installation
534 @cindex installing Guix from binaries
535 @cindex installer script
536 This section describes how to install Guix on an arbitrary system from a
537 self-contained tarball providing binaries for Guix and for all its
538 dependencies. This is often quicker than installing from source, which
539 is described in the next sections. The only requirement is to have
542 @c Note duplicated from the ``Installation'' node.
544 We recommend the use of this
545 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
546 shell installer script}. The script automates the download, installation, and
547 initial configuration steps described below. It should be run as the root
551 Installing goes along these lines:
555 @cindex downloading Guix binary
556 Download the binary tarball from
557 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz},
558 where @var{system} is @code{x86_64-linux} for an @code{x86_64} machine
559 already running the kernel Linux, and so on.
561 @c The following is somewhat duplicated in ``System Installation''.
562 Make sure to download the associated @file{.sig} file and to verify the
563 authenticity of the tarball against it, along these lines:
566 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
567 $ gpg --verify guix-binary-@value{VERSION}.@var{system}.tar.xz.sig
570 If that command fails because you do not have the required public key,
571 then run this command to import it:
574 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
575 -qO - | gpg --import -
579 and rerun the @code{gpg --verify} command.
581 Take note that a warning like ``This key is not certified with a trusted
582 signature!'' is normal.
584 @c end authentication part
587 Now, you need to become the @code{root} user. Depending on your distribution,
588 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
592 # tar --warning=no-timestamp -xf \
593 /path/to/guix-binary-@value{VERSION}.@var{system}.tar.xz
594 # mv var/guix /var/ && mv gnu /
597 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
598 The latter contains a ready-to-use profile for @code{root} (see next
601 Do @emph{not} unpack the tarball on a working Guix system since that
602 would overwrite its own essential files.
604 The @code{--warning=no-timestamp} option makes sure GNU@tie{}tar does
605 not emit warnings about ``implausibly old time stamps'' (such
606 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
608 They stem from the fact that all the
609 files in the archive have their modification time set to zero (which
610 means January 1st, 1970.) This is done on purpose to make sure the
611 archive content is independent of its creation time, thus making it
615 Make the profile available under @file{~root/.config/guix/current}, which is
616 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
619 # mkdir -p ~root/.config/guix
620 # ln -sf /var/guix/profiles/per-user/root/current-guix \
621 ~root/.config/guix/current
624 Source @file{etc/profile} to augment @code{PATH} and other relevant
625 environment variables:
628 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
629 source $GUIX_PROFILE/etc/profile
633 Create the group and user accounts for build users as explained below
634 (@pxref{Build Environment Setup}).
637 Run the daemon, and set it to automatically start on boot.
639 If your host distro uses the systemd init system, this can be achieved
642 @c Versions of systemd that supported symlinked service files are not
643 @c yet widely deployed, so we should suggest that users copy the service
646 @c See this thread for more information:
647 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
650 # cp ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
652 # systemctl start guix-daemon && systemctl enable guix-daemon
655 If your host distro uses the Upstart init system:
658 # initctl reload-configuration
659 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
664 Otherwise, you can still start the daemon manually with:
667 # ~root/.config/guix/current/bin/guix-daemon \
668 --build-users-group=guixbuild
672 Make the @command{guix} command available to other users on the machine,
676 # mkdir -p /usr/local/bin
678 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
681 It is also a good idea to make the Info version of this manual available
685 # mkdir -p /usr/local/share/info
686 # cd /usr/local/share/info
687 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
691 That way, assuming @file{/usr/local/share/info} is in the search path,
692 running @command{info guix} will open this manual (@pxref{Other Info
693 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
697 @cindex substitutes, authorization thereof
698 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
699 (@pxref{Substitutes}), authorize them:
702 # guix archive --authorize < \
703 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
707 Each user may need to perform a few additional steps to make their Guix
708 environment ready for use, @pxref{Application Setup}.
711 Voilà, the installation is complete!
713 You can confirm that Guix is working by installing a sample package into
720 The binary installation tarball can be (re)produced and verified simply
721 by running the following command in the Guix source tree:
724 make guix-binary.@var{system}.tar.xz
728 ...@: which, in turn, runs:
731 guix pack -s @var{system} --localstatedir \
732 --profile-name=current-guix guix
735 @xref{Invoking guix pack}, for more info on this handy tool.
738 @section Requirements
740 This section lists requirements when building Guix from source. The
741 build procedure for Guix is the same as for other GNU software, and is
742 not covered here. Please see the files @file{README} and @file{INSTALL}
743 in the Guix source tree for additional details.
745 @cindex official website
746 GNU Guix is available for download from its website at
747 @url{https://www.gnu.org/software/guix/}.
749 GNU Guix depends on the following packages:
752 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
754 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
757 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
758 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
759 Guile,, gnutls-guile, GnuTLS-Guile});
761 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
764 @c FIXME: Specify a version number once a release has been made.
765 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, from August
767 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON} 3.x;
768 @item @url{https://zlib.net, zlib};
769 @item @url{https://www.gnu.org/software/make/, GNU Make}.
772 The following dependencies are optional:
776 @c Note: We need at least 0.12.0 for 'userauth-gssapi!'.
777 Support for build offloading (@pxref{Daemon Offload Setup}) and
778 @command{guix copy} (@pxref{Invoking guix copy}) depends on
779 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
780 version 0.12.0 or later.
783 When @url{https://www.nongnu.org/lzip/lzlib.html, lzlib} is available, lzlib
784 substitutes can be used and @command{guix publish} can compress substitutes
788 When @url{http://www.bzip.org, libbz2} is available,
789 @command{guix-daemon} can use it to compress build logs.
792 Unless @code{--disable-daemon} was passed to @command{configure}, the
793 following packages are also needed:
796 @item @url{https://gnupg.org/, GNU libgcrypt};
797 @item @url{https://sqlite.org, SQLite 3};
798 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
802 @cindex state directory
803 When configuring Guix on a system that already has a Guix installation,
804 be sure to specify the same state directory as the existing installation
805 using the @code{--localstatedir} option of the @command{configure}
806 script (@pxref{Directory Variables, @code{localstatedir},, standards,
807 GNU Coding Standards}). Usually, this @var{localstatedir} option is
808 set to the value @file{/var}. The @command{configure} script protects
809 against unintended misconfiguration of @var{localstatedir} so you do not
810 inadvertently corrupt your store (@pxref{The Store}).
812 @node Running the Test Suite
813 @section Running the Test Suite
816 After a successful @command{configure} and @code{make} run, it is a good
817 idea to run the test suite. It can help catch issues with the setup or
818 environment, or bugs in Guix itself---and really, reporting test
819 failures is a good way to help improve the software. To run the test
826 Test cases can run in parallel: you can use the @code{-j} option of
827 GNU@tie{}make to speed things up. The first run may take a few minutes
828 on a recent machine; subsequent runs will be faster because the store
829 that is created for test purposes will already have various things in
832 It is also possible to run a subset of the tests by defining the
833 @code{TESTS} makefile variable as in this example:
836 make check TESTS="tests/store.scm tests/cpio.scm"
839 By default, tests results are displayed at a file level. In order to
840 see the details of every individual test cases, it is possible to define
841 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
844 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
847 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
848 @file{test-suite.log} file. Please specify the Guix version being used
849 as well as version numbers of the dependencies (@pxref{Requirements}) in
852 Guix also comes with a whole-system test suite that tests complete
853 Guix System instances. It can only run on systems where
854 Guix is already installed, using:
861 or, again, by defining @code{TESTS} to select a subset of tests to run:
864 make check-system TESTS="basic mcron"
867 These system tests are defined in the @code{(gnu tests @dots{})}
868 modules. They work by running the operating systems under test with
869 lightweight instrumentation in a virtual machine (VM). They can be
870 computationally intensive or rather cheap, depending on whether
871 substitutes are available for their dependencies (@pxref{Substitutes}).
872 Some of them require a lot of storage space to hold VM images.
874 Again in case of test failures, please send @email{bug-guix@@gnu.org}
877 @node Setting Up the Daemon
878 @section Setting Up the Daemon
881 Operations such as building a package or running the garbage collector
882 are all performed by a specialized process, the @dfn{build daemon}, on
883 behalf of clients. Only the daemon may access the store and its
884 associated database. Thus, any operation that manipulates the store
885 goes through the daemon. For instance, command-line tools such as
886 @command{guix package} and @command{guix build} communicate with the
887 daemon (@i{via} remote procedure calls) to instruct it what to do.
889 The following sections explain how to prepare the build daemon's
890 environment. See also @ref{Substitutes}, for information on how to allow
891 the daemon to download pre-built binaries.
894 * Build Environment Setup:: Preparing the isolated build environment.
895 * Daemon Offload Setup:: Offloading builds to remote machines.
896 * SELinux Support:: Using an SELinux policy for the daemon.
899 @node Build Environment Setup
900 @subsection Build Environment Setup
902 @cindex build environment
903 In a standard multi-user setup, Guix and its daemon---the
904 @command{guix-daemon} program---are installed by the system
905 administrator; @file{/gnu/store} is owned by @code{root} and
906 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
907 Guix tools to build packages or otherwise access the store, and the
908 daemon will do it on their behalf, ensuring that the store is kept in a
909 consistent state, and allowing built packages to be shared among users.
912 When @command{guix-daemon} runs as @code{root}, you may not want package
913 build processes themselves to run as @code{root} too, for obvious
914 security reasons. To avoid that, a special pool of @dfn{build users}
915 should be created for use by build processes started by the daemon.
916 These build users need not have a shell and a home directory: they will
917 just be used when the daemon drops @code{root} privileges in build
918 processes. Having several such users allows the daemon to launch
919 distinct build processes under separate UIDs, which guarantees that they
920 do not interfere with each other---an essential feature since builds are
921 regarded as pure functions (@pxref{Introduction}).
923 On a GNU/Linux system, a build user pool may be created like this (using
924 Bash syntax and the @code{shadow} commands):
926 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
927 @c for why `-G' is needed.
929 # groupadd --system guixbuild
930 # for i in `seq -w 1 10`;
932 useradd -g guixbuild -G guixbuild \
933 -d /var/empty -s `which nologin` \
934 -c "Guix build user $i" --system \
940 The number of build users determines how many build jobs may run in
941 parallel, as specified by the @option{--max-jobs} option
942 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
943 @command{guix system vm} and related commands, you may need to add the
944 build users to the @code{kvm} group so they can access @file{/dev/kvm},
945 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
946 (@pxref{Invoking guix system}).
948 The @code{guix-daemon} program may then be run as @code{root} with the
949 following command@footnote{If your machine uses the systemd init system,
950 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
951 file in @file{/etc/systemd/system} will ensure that
952 @command{guix-daemon} is automatically started. Similarly, if your
953 machine uses the Upstart init system, drop the
954 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
955 file in @file{/etc/init}.}:
958 # guix-daemon --build-users-group=guixbuild
963 This way, the daemon starts build processes in a chroot, under one of
964 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
965 environment contains nothing but:
967 @c Keep this list in sync with libstore/build.cc! -----------------------
970 a minimal @code{/dev} directory, created mostly independently from the
971 host @code{/dev}@footnote{``Mostly'', because while the set of files
972 that appear in the chroot's @code{/dev} is fixed, most of these files
973 can only be created if the host has them.};
976 the @code{/proc} directory; it only shows the processes of the container
977 since a separate PID name space is used;
980 @file{/etc/passwd} with an entry for the current user and an entry for
984 @file{/etc/group} with an entry for the user's group;
987 @file{/etc/hosts} with an entry that maps @code{localhost} to
991 a writable @file{/tmp} directory.
994 You can influence the directory where the daemon stores build trees
995 @i{via} the @code{TMPDIR} environment variable. However, the build tree
996 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
997 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
998 This way, the value of @code{TMPDIR} does not leak inside build
999 environments, which avoids discrepancies in cases where build processes
1000 capture the name of their build tree.
1003 The daemon also honors the @code{http_proxy} environment variable for
1004 HTTP downloads it performs, be it for fixed-output derivations
1005 (@pxref{Derivations}) or for substitutes (@pxref{Substitutes}).
1007 If you are installing Guix as an unprivileged user, it is still possible
1008 to run @command{guix-daemon} provided you pass @code{--disable-chroot}.
1009 However, build processes will not be isolated from one another, and not
1010 from the rest of the system. Thus, build processes may interfere with
1011 each other, and may access programs, libraries, and other files
1012 available on the system---making it much harder to view them as
1013 @emph{pure} functions.
1016 @node Daemon Offload Setup
1017 @subsection Using the Offload Facility
1021 When desired, the build daemon can @dfn{offload} derivation builds to
1022 other machines running Guix, using the @code{offload} @dfn{build
1023 hook}@footnote{This feature is available only when
1024 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1025 present.}. When that
1026 feature is enabled, a list of user-specified build machines is read from
1027 @file{/etc/guix/machines.scm}; every time a build is requested, for
1028 instance via @code{guix build}, the daemon attempts to offload it to one
1029 of the machines that satisfy the constraints of the derivation, in
1030 particular its system type---e.g., @file{x86_64-linux}. Missing
1031 prerequisites for the build are copied over SSH to the target machine,
1032 which then proceeds with the build; upon success the output(s) of the
1033 build are copied back to the initial machine.
1035 The @file{/etc/guix/machines.scm} file typically looks like this:
1038 (list (build-machine
1039 (name "eightysix.example.org")
1040 (system "x86_64-linux")
1041 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1043 (speed 2.)) ;incredibly fast!
1046 (name "meeps.example.org")
1047 (system "mips64el-linux")
1048 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1051 (string-append (getenv "HOME")
1052 "/.ssh/identity-for-guix"))))
1056 In the example above we specify a list of two build machines, one for
1057 the @code{x86_64} architecture and one for the @code{mips64el}
1060 In fact, this file is---not surprisingly!---a Scheme file that is
1061 evaluated when the @code{offload} hook is started. Its return value
1062 must be a list of @code{build-machine} objects. While this example
1063 shows a fixed list of build machines, one could imagine, say, using
1064 DNS-SD to return a list of potential build machines discovered in the
1065 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1066 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1069 @deftp {Data Type} build-machine
1070 This data type represents build machines to which the daemon may offload
1071 builds. The important fields are:
1076 The host name of the remote machine.
1079 The system type of the remote machine---e.g., @code{"x86_64-linux"}.
1082 The user account to use when connecting to the remote machine over SSH.
1083 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1084 allow non-interactive logins.
1087 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1088 This is used to authenticate the machine when we connect to it. It is a
1089 long string that looks like this:
1092 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1095 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1096 key can be found in a file such as
1097 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1099 If the machine is running the SSH daemon of GNU@tie{}lsh,
1100 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1101 similar file. It can be converted to the OpenSSH format using
1102 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1105 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1106 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1111 A number of optional fields may be specified:
1115 @item @code{port} (default: @code{22})
1116 Port number of SSH server on the machine.
1118 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1119 The SSH private key file to use when connecting to the machine, in
1120 OpenSSH format. This key must not be protected with a passphrase.
1122 Note that the default value is the private key @emph{of the root
1123 account}. Make sure it exists if you use the default.
1125 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1126 @itemx @code{compression-level} (default: @code{3})
1127 The SSH-level compression methods and compression level requested.
1129 Note that offloading relies on SSH compression to reduce bandwidth usage
1130 when transferring files to and from build machines.
1132 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1133 File name of the Unix-domain socket @command{guix-daemon} is listening
1136 @item @code{parallel-builds} (default: @code{1})
1137 The number of builds that may run in parallel on the machine.
1139 @item @code{speed} (default: @code{1.0})
1140 A ``relative speed factor''. The offload scheduler will tend to prefer
1141 machines with a higher speed factor.
1143 @item @code{features} (default: @code{'()})
1144 A list of strings denoting specific features supported by the machine.
1145 An example is @code{"kvm"} for machines that have the KVM Linux modules
1146 and corresponding hardware support. Derivations can request features by
1147 name, and they will be scheduled on matching build machines.
1152 The @command{guix} command must be in the search path on the build
1153 machines. You can check whether this is the case by running:
1156 ssh build-machine guix repl --version
1159 There is one last thing to do once @file{machines.scm} is in place. As
1160 explained above, when offloading, files are transferred back and forth
1161 between the machine stores. For this to work, you first need to
1162 generate a key pair on each machine to allow the daemon to export signed
1163 archives of files from the store (@pxref{Invoking guix archive}):
1166 # guix archive --generate-key
1170 Each build machine must authorize the key of the master machine so that
1171 it accepts store items it receives from the master:
1174 # guix archive --authorize < master-public-key.txt
1178 Likewise, the master machine must authorize the key of each build machine.
1180 All the fuss with keys is here to express pairwise mutual trust
1181 relations between the master and the build machines. Concretely, when
1182 the master receives files from a build machine (and @i{vice versa}), its
1183 build daemon can make sure they are genuine, have not been tampered
1184 with, and that they are signed by an authorized key.
1186 @cindex offload test
1187 To test whether your setup is operational, run this command on the
1194 This will attempt to connect to each of the build machines specified in
1195 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1196 available on each machine, attempt to export to the machine and import
1197 from it, and report any error in the process.
1199 If you want to test a different machine file, just specify it on the
1203 # guix offload test machines-qualif.scm
1206 Last, you can test the subset of the machines whose name matches a
1207 regular expression like this:
1210 # guix offload test machines.scm '\.gnu\.org$'
1213 @cindex offload status
1214 To display the current load of all build hosts, run this command on the
1218 # guix offload status
1222 @node SELinux Support
1223 @subsection SELinux Support
1225 @cindex SELinux, daemon policy
1226 @cindex mandatory access control, SELinux
1227 @cindex security, guix-daemon
1228 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1229 can be installed on a system where SELinux is enabled, in order to label
1230 Guix files and to specify the expected behavior of the daemon. Since
1231 Guix System does not provide an SELinux base policy, the daemon policy cannot
1232 be used on Guix System.
1234 @subsubsection Installing the SELinux policy
1235 @cindex SELinux, policy installation
1236 To install the policy run this command as root:
1239 semodule -i etc/guix-daemon.cil
1242 Then relabel the file system with @code{restorecon} or by a different
1243 mechanism provided by your system.
1245 Once the policy is installed, the file system has been relabeled, and
1246 the daemon has been restarted, it should be running in the
1247 @code{guix_daemon_t} context. You can confirm this with the following
1251 ps -Zax | grep guix-daemon
1254 Monitor the SELinux log files as you run a command like @code{guix build
1255 hello} to convince yourself that SELinux permits all necessary
1258 @subsubsection Limitations
1259 @cindex SELinux, limitations
1261 This policy is not perfect. Here is a list of limitations or quirks
1262 that should be considered when deploying the provided SELinux policy for
1267 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1268 operations involve contexts that have anything to do with
1269 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1270 but it would be preferrable to define socket rules for only this label.
1273 @code{guix gc} cannot access arbitrary links to profiles. By design,
1274 the file label of the destination of a symlink is independent of the
1275 file label of the link itself. Although all profiles under
1276 $localstatedir are labelled, the links to these profiles inherit the
1277 label of the directory they are in. For links in the user’s home
1278 directory this will be @code{user_home_t}. But for links from the root
1279 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1280 directory, etc, this won’t work. @code{guix gc} would be prevented from
1281 reading and following these links.
1284 The daemon’s feature to listen for TCP connections might no longer work.
1285 This might require extra rules, because SELinux treats network sockets
1286 differently from files.
1289 Currently all files with a name matching the regular expression
1290 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1291 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1292 that name in any profile would be permitted to run in the
1293 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1294 build a package that provides this executable and convince a user to
1295 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1296 At that point SELinux could not prevent it from accessing files that are
1297 allowed for processes in that domain.
1299 We could generate a much more restrictive policy at installation time,
1300 so that only the @emph{exact} file name of the currently installed
1301 @code{guix-daemon} executable would be labelled with
1302 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1303 The downside is that root would have to install or upgrade the policy at
1304 installation time whenever the Guix package that provides the
1305 effectively running @code{guix-daemon} executable is upgraded.
1308 @node Invoking guix-daemon
1309 @section Invoking @command{guix-daemon}
1311 The @command{guix-daemon} program implements all the functionality to
1312 access the store. This includes launching build processes, running the
1313 garbage collector, querying the availability of a build result, etc. It
1314 is normally run as @code{root} like this:
1317 # guix-daemon --build-users-group=guixbuild
1321 For details on how to set it up, @pxref{Setting Up the Daemon}.
1324 @cindex container, build environment
1325 @cindex build environment
1326 @cindex reproducible builds
1327 By default, @command{guix-daemon} launches build processes under
1328 different UIDs, taken from the build group specified with
1329 @code{--build-users-group}. In addition, each build process is run in a
1330 chroot environment that only contains the subset of the store that the
1331 build process depends on, as specified by its derivation
1332 (@pxref{Programming Interface, derivation}), plus a set of specific
1333 system directories. By default, the latter contains @file{/dev} and
1334 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1335 @dfn{container}: in addition to having its own file system tree, it has
1336 a separate mount name space, its own PID name space, network name space,
1337 etc. This helps achieve reproducible builds (@pxref{Features}).
1339 When the daemon performs a build on behalf of the user, it creates a
1340 build directory under @file{/tmp} or under the directory specified by
1341 its @code{TMPDIR} environment variable. This directory is shared with
1342 the container for the duration of the build, though within the container,
1343 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1345 The build directory is automatically deleted upon completion, unless the
1346 build failed and the client specified @option{--keep-failed}
1347 (@pxref{Invoking guix build, @option{--keep-failed}}).
1349 The daemon listens for connections and spawns one sub-process for each session
1350 started by a client (one of the @command{guix} sub-commands.) The
1351 @command{guix processes} command allows you to get an overview of the activity
1352 on your system by viewing each of the active sessions and clients.
1353 @xref{Invoking guix processes}, for more information.
1355 The following command-line options are supported:
1358 @item --build-users-group=@var{group}
1359 Take users from @var{group} to run build processes (@pxref{Setting Up
1360 the Daemon, build users}).
1362 @item --no-substitutes
1364 Do not use substitutes for build products. That is, always build things
1365 locally instead of allowing downloads of pre-built binaries
1366 (@pxref{Substitutes}).
1368 When the daemon runs with @code{--no-substitutes}, clients can still
1369 explicitly enable substitution @i{via} the @code{set-build-options}
1370 remote procedure call (@pxref{The Store}).
1372 @item --substitute-urls=@var{urls}
1373 @anchor{daemon-substitute-urls}
1374 Consider @var{urls} the default whitespace-separated list of substitute
1375 source URLs. When this option is omitted,
1376 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1378 This means that substitutes may be downloaded from @var{urls}, as long
1379 as they are signed by a trusted signature (@pxref{Substitutes}).
1383 Do not use offload builds to other machines (@pxref{Daemon Offload
1384 Setup}). That is, always build things locally instead of offloading
1385 builds to remote machines.
1387 @item --cache-failures
1388 Cache build failures. By default, only successful builds are cached.
1390 When this option is used, @command{guix gc --list-failures} can be used
1391 to query the set of store items marked as failed; @command{guix gc
1392 --clear-failures} removes store items from the set of cached failures.
1393 @xref{Invoking guix gc}.
1395 @item --cores=@var{n}
1397 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1400 The default value is @code{0}, but it may be overridden by clients, such
1401 as the @code{--cores} option of @command{guix build} (@pxref{Invoking
1404 The effect is to define the @code{NIX_BUILD_CORES} environment variable
1405 in the build process, which can then use it to exploit internal
1406 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1408 @item --max-jobs=@var{n}
1410 Allow at most @var{n} build jobs in parallel. The default value is
1411 @code{1}. Setting it to @code{0} means that no builds will be performed
1412 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1413 Setup}), or simply fail.
1415 @item --max-silent-time=@var{seconds}
1416 When the build or substitution process remains silent for more than
1417 @var{seconds}, terminate it and report a build failure.
1419 The default value is @code{0}, which disables the timeout.
1421 The value specified here can be overridden by clients (@pxref{Common
1422 Build Options, @code{--max-silent-time}}).
1424 @item --timeout=@var{seconds}
1425 Likewise, when the build or substitution process lasts for more than
1426 @var{seconds}, terminate it and report a build failure.
1428 The default value is @code{0}, which disables the timeout.
1430 The value specified here can be overridden by clients (@pxref{Common
1431 Build Options, @code{--timeout}}).
1433 @item --rounds=@var{N}
1434 Build each derivation @var{n} times in a row, and raise an error if
1435 consecutive build results are not bit-for-bit identical. Note that this
1436 setting can be overridden by clients such as @command{guix build}
1437 (@pxref{Invoking guix build}).
1439 When used in conjunction with @option{--keep-failed}, the differing
1440 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1441 This makes it easy to look for differences between the two results.
1444 Produce debugging output.
1446 This is useful to debug daemon start-up issues, but then it may be
1447 overridden by clients, for example the @code{--verbosity} option of
1448 @command{guix build} (@pxref{Invoking guix build}).
1450 @item --chroot-directory=@var{dir}
1451 Add @var{dir} to the build chroot.
1453 Doing this may change the result of build processes---for instance if
1454 they use optional dependencies found in @var{dir} when it is available,
1455 and not otherwise. For that reason, it is not recommended to do so.
1456 Instead, make sure that each derivation declares all the inputs that it
1459 @item --disable-chroot
1460 Disable chroot builds.
1462 Using this option is not recommended since, again, it would allow build
1463 processes to gain access to undeclared dependencies. It is necessary,
1464 though, when @command{guix-daemon} is running under an unprivileged user
1467 @item --log-compression=@var{type}
1468 Compress build logs according to @var{type}, one of @code{gzip},
1469 @code{bzip2}, or @code{none}.
1471 Unless @code{--lose-logs} is used, all the build logs are kept in the
1472 @var{localstatedir}. To save space, the daemon automatically compresses
1473 them with bzip2 by default.
1475 @item --disable-deduplication
1476 @cindex deduplication
1477 Disable automatic file ``deduplication'' in the store.
1479 By default, files added to the store are automatically ``deduplicated'':
1480 if a newly added file is identical to another one found in the store,
1481 the daemon makes the new file a hard link to the other file. This can
1482 noticeably reduce disk usage, at the expense of slightly increased
1483 input/output load at the end of a build process. This option disables
1486 @item --gc-keep-outputs[=yes|no]
1487 Tell whether the garbage collector (GC) must keep outputs of live
1491 @cindex garbage collector roots
1492 When set to ``yes'', the GC will keep the outputs of any live derivation
1493 available in the store---the @code{.drv} files. The default is ``no'',
1494 meaning that derivation outputs are kept only if they are reachable from a GC
1495 root. @xref{Invoking guix gc}, for more on GC roots.
1497 @item --gc-keep-derivations[=yes|no]
1498 Tell whether the garbage collector (GC) must keep derivations
1499 corresponding to live outputs.
1501 When set to ``yes'', as is the case by default, the GC keeps
1502 derivations---i.e., @code{.drv} files---as long as at least one of their
1503 outputs is live. This allows users to keep track of the origins of
1504 items in their store. Setting it to ``no'' saves a bit of disk space.
1506 In this way, setting @code{--gc-keep-derivations} to ``yes'' causes liveness
1507 to flow from outputs to derivations, and setting @code{--gc-keep-outputs} to
1508 ``yes'' causes liveness to flow from derivations to outputs. When both are
1509 set to ``yes'', the effect is to keep all the build prerequisites (the
1510 sources, compiler, libraries, and other build-time tools) of live objects in
1511 the store, regardless of whether these prerequisites are reachable from a GC
1512 root. This is convenient for developers since it saves rebuilds or downloads.
1514 @item --impersonate-linux-2.6
1515 On Linux-based systems, impersonate Linux 2.6. This means that the
1516 kernel's @code{uname} system call will report 2.6 as the release number.
1518 This might be helpful to build programs that (usually wrongfully) depend
1519 on the kernel version number.
1522 Do not keep build logs. By default they are kept under
1523 @code{@var{localstatedir}/guix/log}.
1525 @item --system=@var{system}
1526 Assume @var{system} as the current system type. By default it is the
1527 architecture/kernel pair found at configure time, such as
1528 @code{x86_64-linux}.
1530 @item --listen=@var{endpoint}
1531 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1532 as the file name of a Unix-domain socket if it starts with
1533 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1534 host name or host name and port to listen to. Here are a few examples:
1537 @item --listen=/gnu/var/daemon
1538 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1539 creating it if needed.
1541 @item --listen=localhost
1542 @cindex daemon, remote access
1543 @cindex remote access to the daemon
1544 @cindex daemon, cluster setup
1545 @cindex clusters, daemon setup
1546 Listen for TCP connections on the network interface corresponding to
1547 @code{localhost}, on port 44146.
1549 @item --listen=128.0.0.42:1234
1550 Listen for TCP connections on the network interface corresponding to
1551 @code{128.0.0.42}, on port 1234.
1554 This option can be repeated multiple times, in which case
1555 @command{guix-daemon} accepts connections on all the specified
1556 endpoints. Users can tell client commands what endpoint to connect to
1557 by setting the @code{GUIX_DAEMON_SOCKET} environment variable
1558 (@pxref{The Store, @code{GUIX_DAEMON_SOCKET}}).
1561 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1562 @code{--listen=@var{host}} is suitable on local networks, such as
1563 clusters, where only trusted nodes may connect to the build daemon. In
1564 other cases where remote access to the daemon is needed, we recommend
1565 using Unix-domain sockets along with SSH.
1568 When @code{--listen} is omitted, @command{guix-daemon} listens for
1569 connections on the Unix-domain socket located at
1570 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1574 @node Application Setup
1575 @section Application Setup
1577 @cindex foreign distro
1578 When using Guix on top of GNU/Linux distribution other than Guix System---a
1579 so-called @dfn{foreign distro}---a few additional steps are needed to
1580 get everything in place. Here are some of them.
1584 @anchor{locales-and-locpath}
1585 @cindex locales, when not on Guix System
1587 @vindex GUIX_LOCPATH
1588 Packages installed @i{via} Guix will not use the locale data of the
1589 host system. Instead, you must first install one of the locale packages
1590 available with Guix and then define the @code{GUIX_LOCPATH} environment
1594 $ guix install glibc-locales
1595 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1598 Note that the @code{glibc-locales} package contains data for all the
1599 locales supported by the GNU@tie{}libc and weighs in at around
1600 110@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1601 limited to a few UTF-8 locales.
1603 The @code{GUIX_LOCPATH} variable plays a role similar to @code{LOCPATH}
1604 (@pxref{Locale Names, @code{LOCPATH},, libc, The GNU C Library Reference
1605 Manual}). There are two important differences though:
1609 @code{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1610 provided by foreign distros. Thus, using @code{GUIX_LOCPATH} allows you
1611 to make sure the programs of the foreign distro will not end up loading
1612 incompatible locale data.
1615 libc suffixes each entry of @code{GUIX_LOCPATH} with @code{/X.Y}, where
1616 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1617 should your Guix profile contain a mixture of programs linked against
1618 different libc version, each libc version will only try to load locale
1619 data in the right format.
1622 This is important because the locale data format used by different libc
1623 versions may be incompatible.
1625 @subsection Name Service Switch
1627 @cindex name service switch, glibc
1628 @cindex NSS (name service switch), glibc
1629 @cindex nscd (name service caching daemon)
1630 @cindex name service caching daemon (nscd)
1631 When using Guix on a foreign distro, we @emph{strongly recommend} that
1632 the system run the GNU C library's @dfn{name service cache daemon},
1633 @command{nscd}, which should be listening on the
1634 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1635 installed with Guix may fail to look up host names or user accounts, or
1636 may even crash. The next paragraphs explain why.
1638 @cindex @file{nsswitch.conf}
1639 The GNU C library implements a @dfn{name service switch} (NSS), which is
1640 an extensible mechanism for ``name lookups'' in general: host name
1641 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1642 The GNU C Library Reference Manual}).
1644 @cindex Network information service (NIS)
1645 @cindex NIS (Network information service)
1646 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1647 lookup implementations: for example, the @code{nss-mdns} plugin allow
1648 resolution of @code{.local} host names, the @code{nis} plugin allows
1649 user account lookup using the Network information service (NIS), and so
1650 on. These extra ``lookup services'' are configured system-wide in
1651 @file{/etc/nsswitch.conf}, and all the programs running on the system
1652 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1655 When they perform a name lookup---for instance by calling the
1656 @code{getaddrinfo} function in C---applications first try to connect to
1657 the nscd; on success, nscd performs name lookups on their behalf. If
1658 the nscd is not running, then they perform the name lookup by
1659 themselves, by loading the name lookup services into their own address
1660 space and running it. These name lookup services---the
1661 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1662 the host system's C library, rather than from the C library the
1663 application is linked against (the C library coming from Guix).
1665 And this is where the problem is: if your application is linked against
1666 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1667 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1668 likely crash or have its name lookups fail unexpectedly.
1670 Running @command{nscd} on the system, among other advantages, eliminates
1671 this binary incompatibility problem because those @code{libnss_*.so}
1672 files are loaded in the @command{nscd} process, not in applications
1675 @subsection X11 Fonts
1678 The majority of graphical applications use Fontconfig to locate and
1679 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1680 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1681 by default. Thus, to allow graphical applications installed with Guix
1682 to display fonts, you have to install fonts with Guix as well.
1683 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1684 @code{font-gnu-freefont-ttf}.
1686 To display text written in Chinese languages, Japanese, or Korean in
1687 graphical applications, consider installing
1688 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1689 has multiple outputs, one per language family (@pxref{Packages with
1690 Multiple Outputs}). For instance, the following command installs fonts
1691 for Chinese languages:
1694 guix install font-adobe-source-han-sans:cn
1697 @cindex @code{xterm}
1698 Older programs such as @command{xterm} do not use Fontconfig and instead
1699 rely on server-side font rendering. Such programs require to specify a
1700 full name of a font using XLFD (X Logical Font Description), like this:
1703 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1706 To be able to use such full names for the TrueType fonts installed in
1707 your Guix profile, you need to extend the font path of the X server:
1709 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1710 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1712 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1715 @cindex @code{xlsfonts}
1716 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1717 to make sure your TrueType fonts are listed there.
1719 @cindex @code{fc-cache}
1721 After installing fonts you may have to refresh the font cache to use
1722 them in applications. The same applies when applications installed via
1723 Guix do not seem to find fonts. To force rebuilding of the font cache
1724 run @code{fc-cache -rv}. The @code{fc-cache} command is provided by
1725 the @code{fontconfig} package.
1727 @subsection X.509 Certificates
1729 @cindex @code{nss-certs}
1730 The @code{nss-certs} package provides X.509 certificates, which allow
1731 programs to authenticate Web servers accessed over HTTPS.
1733 When using Guix on a foreign distro, you can install this package and
1734 define the relevant environment variables so that packages know where to
1735 look for certificates. @xref{X.509 Certificates}, for detailed
1738 @subsection Emacs Packages
1740 @cindex @code{emacs}
1741 When you install Emacs packages with Guix, the elisp files may be placed
1742 either in @file{$HOME/.guix-profile/share/emacs/site-lisp/} or in
1744 @file{$HOME/.guix-profile/share/emacs/site-lisp/guix.d/}. The latter
1745 directory exists because potentially there may exist thousands of Emacs
1746 packages and storing all their files in a single directory may not be
1747 reliable (because of name conflicts). So we think using a separate
1748 directory for each package is a good idea. It is very similar to how
1749 the Emacs package system organizes the file structure (@pxref{Package
1750 Files,,, emacs, The GNU Emacs Manual}).
1752 By default, Emacs (installed with Guix) ``knows'' where these packages
1753 are placed, so you do not need to perform any configuration. If, for
1754 some reason, you want to avoid auto-loading Emacs packages installed
1755 with Guix, you can do so by running Emacs with @code{--no-site-file}
1756 option (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1758 @subsection The GCC toolchain
1763 Guix offers individual compiler packages such as @code{gcc} but if you
1764 are in need of a complete toolchain for compiling and linking source
1765 code what you really want is the @code{gcc-toolchain} package. This
1766 package provides a complete GCC toolchain for C/C++ development,
1767 including GCC itself, the GNU C Library (headers and binaries, plus
1768 debugging symbols in the @code{debug} output), Binutils, and a linker
1771 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
1772 passed to the linker, add corresponding @code{-rpath} arguments, and
1773 invoke the actual linker with this new set of arguments. You can instruct the
1774 wrapper to refuse to link against libraries not in the store by setting the
1775 @code{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
1777 @node Upgrading Guix
1778 @section Upgrading Guix
1780 @cindex Upgrading Guix, on a foreign distro
1782 To upgrade Guix, run:
1788 @xref{Invoking guix pull}, for more information.
1790 @cindex upgrading Guix for the root user, on a foreign distro
1791 @cindex upgrading the Guix daemon, on a foreign distro
1792 @cindex @command{guix pull} for the root user, on a foreign distro
1794 On a foreign distro, you can upgrade the build daemon by running:
1801 followed by (assuming your distro uses the systemd service management
1805 systemctl restart guix-daemon.service
1808 On Guix System, upgrading the daemon is achieved by reconfiguring the
1809 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1813 @c *********************************************************************
1814 @node System Installation
1815 @chapter System Installation
1817 @cindex installing Guix System
1818 @cindex Guix System, installation
1819 This section explains how to install Guix System
1820 on a machine. Guix, as a package manager, can
1821 also be installed on top of a running GNU/Linux system,
1822 @pxref{Installation}.
1826 @c This paragraph is for people reading this from tty2 of the
1827 @c installation image.
1828 You are reading this documentation with an Info reader. For details on
1829 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1830 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1831 Info}. Hit @kbd{l} afterwards to come back here.
1833 Alternately, run @command{info info} in another tty to keep the manual
1839 * Limitations:: What you can expect.
1840 * Hardware Considerations:: Supported hardware.
1841 * USB Stick and DVD Installation:: Preparing the installation medium.
1842 * Preparing for Installation:: Networking, partitioning, etc.
1843 * Guided Graphical Installation:: Easy graphical installation.
1844 * Manual Installation:: Manual installation for wizards.
1845 * After System Installation:: When installation succeeded.
1846 * Installing Guix in a VM:: Guix System playground.
1847 * Building the Installation Image:: How this comes to be.
1851 @section Limitations
1853 We consider Guix System to be ready for a wide range of ``desktop'' and server
1854 use cases. The reliability guarantees it provides---transactional upgrades
1855 and rollbacks, reproducibility---make it a solid foundation.
1857 Nevertheless, before you proceed with the installation, be aware of the
1858 following noteworthy limitations applicable to version @value{VERSION}:
1862 Support for the Logical Volume Manager (LVM) is missing.
1865 More and more system services are provided (@pxref{Services}), but some
1869 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1870 as well as a number of X11 window managers. However, KDE is currently
1874 More than a disclaimer, this is an invitation to report issues (and success
1875 stories!), and to join us in improving it. @xref{Contributing}, for more
1879 @node Hardware Considerations
1880 @section Hardware Considerations
1882 @cindex hardware support on Guix System
1883 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
1884 builds around the kernel Linux-libre, which means that only hardware for
1885 which free software drivers and firmware exist is supported. Nowadays,
1886 a wide range of off-the-shelf hardware is supported on
1887 GNU/Linux-libre---from keyboards to graphics cards to scanners and
1888 Ethernet controllers. Unfortunately, there are still areas where
1889 hardware vendors deny users control over their own computing, and such
1890 hardware is not supported on Guix System.
1892 @cindex WiFi, hardware support
1893 One of the main areas where free drivers or firmware are lacking is WiFi
1894 devices. WiFi devices known to work include those using Atheros chips
1895 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
1896 driver, and those using Broadcom/AirForce chips (BCM43xx with
1897 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
1898 Linux-libre driver. Free firmware exists for both and is available
1899 out-of-the-box on Guix System, as part of @code{%base-firmware}
1900 (@pxref{operating-system Reference, @code{firmware}}).
1902 @cindex RYF, Respects Your Freedom
1903 The @uref{https://www.fsf.org/, Free Software Foundation} runs
1904 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
1905 certification program for hardware products that respect your freedom
1906 and your privacy and ensure that you have control over your device. We
1907 encourage you to check the list of RYF-certified devices.
1909 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
1910 web site. It contains a catalog of hardware devices with information
1911 about their support in GNU/Linux.
1914 @node USB Stick and DVD Installation
1915 @section USB Stick and DVD Installation
1917 An ISO-9660 installation image that can be written to a USB stick or
1918 burnt to a DVD can be downloaded from
1919 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
1920 where @var{system} is one of:
1924 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
1927 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
1930 @c start duplication of authentication part from ``Binary Installation''
1931 Make sure to download the associated @file{.sig} file and to verify the
1932 authenticity of the image against it, along these lines:
1935 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1936 $ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
1939 If that command fails because you do not have the required public key,
1940 then run this command to import it:
1943 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
1944 -qO - | gpg --import -
1948 and rerun the @code{gpg --verify} command.
1950 Take note that a warning like ``This key is not certified with a trusted
1951 signature!'' is normal.
1955 This image contains the tools necessary for an installation.
1956 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
1958 @unnumberedsubsec Copying to a USB Stick
1960 To copy the image to a USB stick, follow these steps:
1964 Decompress the image using the @command{xz} command:
1967 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1971 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
1972 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
1973 copy the image with:
1976 dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
1980 Access to @file{/dev/sdX} usually requires root privileges.
1983 @unnumberedsubsec Burning on a DVD
1985 To copy the image to a DVD, follow these steps:
1989 Decompress the image using the @command{xz} command:
1992 xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
1996 Insert a blank DVD into your machine, and determine
1997 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
1998 copy the image with:
2001 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
2004 Access to @file{/dev/srX} usually requires root privileges.
2007 @unnumberedsubsec Booting
2009 Once this is done, you should be able to reboot the system and boot from
2010 the USB stick or DVD. The latter usually requires you to get in the
2011 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2012 In order to boot from Libreboot, switch to the command mode by pressing
2013 the @kbd{c} key and type @command{search_grub usb}.
2015 @xref{Installing Guix in a VM}, if, instead, you would like to install
2016 Guix System in a virtual machine (VM).
2019 @node Preparing for Installation
2020 @section Preparing for Installation
2022 Once you have booted, you can use the guided graphical installer, which makes
2023 it easy to get started (@pxref{Guided Graphical Installation}). Alternately,
2024 if you are already familiar with GNU/Linux and if you want more control than
2025 what the graphical installer provides, you can choose the ``manual''
2026 installation process (@pxref{Manual Installation}).
2028 The graphical installer is available on TTY1. You can obtain root shells on
2029 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2030 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2031 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2032 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2033 which allows you to select text with the left mouse button and to paste it
2034 with the middle button.
2037 Installation requires access to the Internet so that any missing
2038 dependencies of your system configuration can be downloaded. See the
2039 ``Networking'' section below.
2042 @node Guided Graphical Installation
2043 @section Guided Graphical Installation
2045 The graphical installer is a text-based user interface. It will guide you,
2046 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2048 The first dialog boxes allow you to set up the system as you use it during the
2049 installation: you can choose the language, keyboard layout, and set up
2050 networking, which will be used during the installation. The image below shows
2051 the networking dialog.
2053 @image{images/installer-network,5in,, networking setup with the graphical installer}
2055 Later steps allow you to partition your hard disk, as shown in the image
2056 below, to choose whether or not to use encrypted file systems, to enter the
2057 host name and root password, and to create an additional account, among other
2060 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2062 Note that, at any time, the installer allows you to exit the current
2063 installation step and resume at a previous step, as show in the image below.
2065 @image{images/installer-resume,5in,, resuming the installation process}
2067 Once you're done, the installer produces an operating system configuration and
2068 displays it (@pxref{Using the Configuration System}). At that point you can
2069 hit ``OK'' and installation will proceed. On success, you can reboot into the
2070 new system and enjoy. @xref{After System Installation}, for what's next!
2073 @node Manual Installation
2074 @section Manual Installation
2076 This section describes how you would ``manually'' install GNU@tie{}Guix System
2077 on your machine. This option requires familiarity with GNU/Linux, with the
2078 shell, and with common administration tools. If you think this is not for
2079 you, consider using the guided graphical installer (@pxref{Guided Graphical
2082 The installation system provides root shells on TTYs 3 to 6; press
2083 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2084 many common tools needed to install the system. But it is also a full-blown
2085 Guix System, which means that you can install additional packages, should you
2086 need it, using @command{guix package} (@pxref{Invoking guix package}).
2089 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2090 * Proceeding with the Installation:: Installing.
2093 @node Keyboard Layout and Networking and Partitioning
2094 @subsection Keyboard Layout, Networking, and Partitioning
2096 Before you can install the system, you may want to adjust the keyboard layout,
2097 set up networking, and partition your target hard disk. This section will
2098 guide you through this.
2100 @subsubsection Keyboard Layout
2102 @cindex keyboard layout
2103 The installation image uses the US qwerty keyboard layout. If you want
2104 to change it, you can use the @command{loadkeys} command. For example,
2105 the following command selects the Dvorak keyboard layout:
2111 See the files under @file{/run/current-system/profile/share/keymaps} for
2112 a list of available keyboard layouts. Run @command{man loadkeys} for
2115 @subsubsection Networking
2117 Run the following command to see what your network interfaces are called:
2124 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2130 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2131 Wired interfaces have a name starting with @samp{e}; for example, the
2132 interface corresponding to the first on-board Ethernet controller is
2133 called @samp{eno1}. Wireless interfaces have a name starting with
2134 @samp{w}, like @samp{w1p2s0}.
2137 @item Wired connection
2138 To configure a wired network run the following command, substituting
2139 @var{interface} with the name of the wired interface you want to use.
2142 ifconfig @var{interface} up
2146 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2149 ip link set @var{interface} up
2152 @item Wireless connection
2155 To configure wireless networking, you can create a configuration file
2156 for the @command{wpa_supplicant} configuration tool (its location is not
2157 important) using one of the available text editors such as
2161 nano wpa_supplicant.conf
2164 As an example, the following stanza can go to this file and will work
2165 for many wireless networks, provided you give the actual SSID and
2166 passphrase for the network you are connecting to:
2170 ssid="@var{my-ssid}"
2172 psk="the network's secret passphrase"
2176 Start the wireless service and run it in the background with the
2177 following command (substitute @var{interface} with the name of the
2178 network interface you want to use):
2181 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2184 Run @command{man wpa_supplicant} for more information.
2188 At this point, you need to acquire an IP address. On a network where IP
2189 addresses are automatically assigned @i{via} DHCP, you can run:
2192 dhclient -v @var{interface}
2195 Try to ping a server to see if networking is up and running:
2201 Setting up network access is almost always a requirement because the
2202 image does not contain all the software and tools that may be needed.
2204 @cindex installing over SSH
2205 If you want to, you can continue the installation remotely by starting
2209 herd start ssh-daemon
2212 Make sure to either set a password with @command{passwd}, or configure
2213 OpenSSH public key authentication before logging in.
2215 @subsubsection Disk Partitioning
2217 Unless this has already been done, the next step is to partition, and
2218 then format the target partition(s).
2220 The installation image includes several partitioning tools, including
2221 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2222 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2223 the partition layout you want:
2229 If your disk uses the GUID Partition Table (GPT) format and you plan to
2230 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2231 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2234 @cindex EFI, installation
2235 @cindex UEFI, installation
2236 @cindex ESP, EFI system partition
2237 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2238 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2239 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2242 parted /dev/sda set 1 esp on
2246 @vindex grub-bootloader
2247 @vindex grub-efi-bootloader
2248 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2249 @file{/sys/firmware/efi} exists in the installation image, then you should
2250 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2251 Otherwise you should use the BIOS-based GRUB, known as
2252 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2256 Once you are done partitioning the target hard disk drive, you have to
2257 create a file system on the relevant partition(s)@footnote{Currently
2258 Guix System only supports ext4, btrfs, and JFS file systems. In particular,
2259 code that reads file system UUIDs and labels only works for these file system
2260 types.}. For the ESP, if you have one and assuming it is
2261 @file{/dev/sda1}, run:
2264 mkfs.fat -F32 /dev/sda1
2267 Preferably, assign file systems a label so that you can easily and
2268 reliably refer to them in @code{file-system} declarations (@pxref{File
2269 Systems}). This is typically done using the @code{-L} option of
2270 @command{mkfs.ext4} and related commands. So, assuming the target root
2271 partition lives at @file{/dev/sda2}, a file system with the label
2272 @code{my-root} can be created with:
2275 mkfs.ext4 -L my-root /dev/sda2
2278 @cindex encrypted disk
2279 If you are instead planning to encrypt the root partition, you can use
2280 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2281 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2282 @code{man cryptsetup}} for more information.) Assuming you want to
2283 store the root partition on @file{/dev/sda2}, the command sequence would
2284 be along these lines:
2287 cryptsetup luksFormat /dev/sda2
2288 cryptsetup open --type luks /dev/sda2 my-partition
2289 mkfs.ext4 -L my-root /dev/mapper/my-partition
2292 Once that is done, mount the target file system under @file{/mnt}
2293 with a command like (again, assuming @code{my-root} is the label of the
2297 mount LABEL=my-root /mnt
2300 Also mount any other file systems you would like to use on the target
2301 system relative to this path. If you have opted for @file{/boot/efi} as an
2302 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2303 found by @code{guix system init} afterwards.
2305 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2306 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2307 sure to initialize them with @command{mkswap}. Assuming you have one
2308 swap partition on @file{/dev/sda3}, you would run:
2315 Alternatively, you may use a swap file. For example, assuming that in
2316 the new system you want to use the file @file{/swapfile} as a swap file,
2317 you would run@footnote{This example will work for many types of file
2318 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2319 btrfs), the required steps may be different. For details, see the
2320 manual pages for @command{mkswap} and @command{swapon}.}:
2323 # This is 10 GiB of swap space. Adjust "count" to change the size.
2324 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2325 # For security, make the file readable and writable only by root.
2326 chmod 600 /mnt/swapfile
2327 mkswap /mnt/swapfile
2328 swapon /mnt/swapfile
2331 Note that if you have encrypted the root partition and created a swap
2332 file in its file system as described above, then the encryption also
2333 protects the swap file, just like any other file in that file system.
2335 @node Proceeding with the Installation
2336 @subsection Proceeding with the Installation
2338 With the target partitions ready and the target root mounted on
2339 @file{/mnt}, we're ready to go. First, run:
2342 herd start cow-store /mnt
2345 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2346 during the installation phase are written to the target disk on @file{/mnt}
2347 rather than kept in memory. This is necessary because the first phase of
2348 the @command{guix system init} command (see below) entails downloads or
2349 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2351 Next, you have to edit a file and
2352 provide the declaration of the operating system to be installed. To
2353 that end, the installation system comes with three text editors. We
2354 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2355 supports syntax highlighting and parentheses matching; other editors
2356 include GNU Zile (an Emacs clone), and
2357 nvi (a clone of the original BSD @command{vi} editor).
2358 We strongly recommend storing that file on the target root file system, say,
2359 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2360 configuration file once you have rebooted into the newly-installed system.
2362 @xref{Using the Configuration System}, for an overview of the
2363 configuration file. The example configurations discussed in that
2364 section are available under @file{/etc/configuration} in the
2365 installation image. Thus, to get started with a system configuration
2366 providing a graphical display server (a ``desktop'' system), you can run
2367 something along these lines:
2371 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2372 # nano /mnt/etc/config.scm
2375 You should pay attention to what your configuration file contains, and
2380 Make sure the @code{bootloader-configuration} form refers to the target
2381 you want to install GRUB on. It should mention @code{grub-bootloader} if
2382 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2383 for newer UEFI systems. For legacy systems, the @code{target} field
2384 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2385 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2386 currently mounted and a @code{file-system} entry is specified in your
2390 Be sure that your file system labels match the value of their respective
2391 @code{device} fields in your @code{file-system} configuration, assuming
2392 your @code{file-system} configuration uses the @code{file-system-label}
2393 procedure in its @code{device} field.
2396 If there are encrypted or RAID partitions, make sure to add a
2397 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2400 Once you are done preparing the configuration file, the new system must
2401 be initialized (remember that the target root file system is mounted
2405 guix system init /mnt/etc/config.scm /mnt
2409 This copies all the necessary files and installs GRUB on
2410 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2411 more information, @pxref{Invoking guix system}. This command may trigger
2412 downloads or builds of missing packages, which can take some time.
2414 Once that command has completed---and hopefully succeeded!---you can run
2415 @command{reboot} and boot into the new system. The @code{root} password
2416 in the new system is initially empty; other users' passwords need to be
2417 initialized by running the @command{passwd} command as @code{root},
2418 unless your configuration specifies otherwise
2419 (@pxref{user-account-password, user account passwords}).
2420 @xref{After System Installation}, for what's next!
2423 @node After System Installation
2424 @section After System Installation
2426 Success, you've now booted into Guix System! From then on, you can update the
2427 system whenever you want by running, say:
2431 sudo guix system reconfigure /etc/config.scm
2435 This builds a new system generation with the latest packages and services
2436 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2437 your system includes the latest security updates (@pxref{Security Updates}).
2439 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2441 @cindex sudo vs. @command{guix pull}
2442 Note that @command{sudo guix} runs your user's @command{guix} command and
2443 @emph{not} root's, because @command{sudo} leaves @code{PATH} unchanged. To
2444 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2446 The difference matters here, because @command{guix pull} updates
2447 the @command{guix} command and package definitions only for the user it is ran
2448 as. This means that if you choose to use @command{guix system reconfigure} in
2449 root's login shell, you'll need to @command{guix pull} separately.
2452 Join us on @code{#guix} on the Freenode IRC network or on
2453 @email{guix-devel@@gnu.org} to share your experience!
2456 @node Installing Guix in a VM
2457 @section Installing Guix in a Virtual Machine
2459 @cindex virtual machine, Guix System installation
2460 @cindex virtual private server (VPS)
2461 @cindex VPS (virtual private server)
2462 If you'd like to install Guix System in a virtual machine (VM) or on a
2463 virtual private server (VPS) rather than on your beloved machine, this
2466 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2467 disk image, follow these steps:
2471 First, retrieve and decompress the Guix system installation image as
2472 described previously (@pxref{USB Stick and DVD Installation}).
2475 Create a disk image that will hold the installed system. To make a
2476 qcow2-formatted disk image, use the @command{qemu-img} command:
2479 qemu-img create -f qcow2 guix-system.img 50G
2482 The resulting file will be much smaller than 50 GB (typically less than
2483 1 MB), but it will grow as the virtualized storage device is filled up.
2486 Boot the USB installation image in an VM:
2489 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2490 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2491 -drive file=guix-system.img \
2492 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2495 @code{-enable-kvm} is optional, but significantly improves performance,
2496 @pxref{Running Guix in a VM}.
2499 You're now root in the VM, proceed with the installation process.
2500 @xref{Preparing for Installation}, and follow the instructions.
2503 Once installation is complete, you can boot the system that's on your
2504 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2507 @node Building the Installation Image
2508 @section Building the Installation Image
2510 @cindex installation image
2511 The installation image described above was built using the @command{guix
2512 system} command, specifically:
2515 guix system disk-image --file-system-type=iso9660 \
2516 gnu/system/install.scm
2519 Have a look at @file{gnu/system/install.scm} in the source tree,
2520 and see also @ref{Invoking guix system} for more information
2521 about the installation image.
2523 @section Building the Installation Image for ARM Boards
2525 Many ARM boards require a specific variant of the
2526 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2528 If you build a disk image and the bootloader is not available otherwise
2529 (on another boot drive etc), it's advisable to build an image that
2530 includes the bootloader, specifically:
2533 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2536 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2537 board, a list of possible boards will be printed.
2539 @c *********************************************************************
2540 @node Package Management
2541 @chapter Package Management
2544 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2545 remove software packages, without having to know about their build
2546 procedures or dependencies. Guix also goes beyond this obvious set of
2549 This chapter describes the main features of Guix, as well as the
2550 package management tools it provides. Along with the command-line
2551 interface described below (@pxref{Invoking guix package, @code{guix
2552 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2553 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2554 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2558 guix install emacs-guix
2562 * Features:: How Guix will make your life brighter.
2563 * Invoking guix package:: Package installation, removal, etc.
2564 * Substitutes:: Downloading pre-built binaries.
2565 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2566 * Invoking guix gc:: Running the garbage collector.
2567 * Invoking guix pull:: Fetching the latest Guix and distribution.
2568 * Channels:: Customizing the package collection.
2569 * Invoking guix time-machine:: Running an older revision of Guix.
2570 * Inferiors:: Interacting with another revision of Guix.
2571 * Invoking guix describe:: Display information about your Guix revision.
2572 * Invoking guix archive:: Exporting and importing store files.
2578 When using Guix, each package ends up in the @dfn{package store}, in its
2579 own directory---something that resembles
2580 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2582 Instead of referring to these directories, users have their own
2583 @dfn{profile}, which points to the packages that they actually want to
2584 use. These profiles are stored within each user's home directory, at
2585 @code{$HOME/.guix-profile}.
2587 For example, @code{alice} installs GCC 4.7.2. As a result,
2588 @file{/home/alice/.guix-profile/bin/gcc} points to
2589 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2590 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2591 simply continues to point to
2592 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2593 coexist on the same system without any interference.
2595 The @command{guix package} command is the central tool to manage
2596 packages (@pxref{Invoking guix package}). It operates on the per-user
2597 profiles, and can be used @emph{with normal user privileges}.
2599 @cindex transactions
2600 The command provides the obvious install, remove, and upgrade
2601 operations. Each invocation is actually a @emph{transaction}: either
2602 the specified operation succeeds, or nothing happens. Thus, if the
2603 @command{guix package} process is terminated during the transaction,
2604 or if a power outage occurs during the transaction, then the user's
2605 profile remains in its previous state, and remains usable.
2607 In addition, any package transaction may be @emph{rolled back}. So, if,
2608 for example, an upgrade installs a new version of a package that turns
2609 out to have a serious bug, users may roll back to the previous instance
2610 of their profile, which was known to work well. Similarly, the global
2611 system configuration on Guix is subject to
2612 transactional upgrades and roll-back
2613 (@pxref{Using the Configuration System}).
2615 All packages in the package store may be @emph{garbage-collected}.
2616 Guix can determine which packages are still referenced by user
2617 profiles, and remove those that are provably no longer referenced
2618 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2619 generations of their profile so that the packages they refer to can be
2622 @cindex reproducibility
2623 @cindex reproducible builds
2624 Guix takes a @dfn{purely functional} approach to package
2625 management, as described in the introduction (@pxref{Introduction}).
2626 Each @file{/gnu/store} package directory name contains a hash of all the
2627 inputs that were used to build that package---compiler, libraries, build
2628 scripts, etc. This direct correspondence allows users to make sure a
2629 given package installation matches the current state of their
2630 distribution. It also helps maximize @dfn{build reproducibility}:
2631 thanks to the isolated build environments that are used, a given build
2632 is likely to yield bit-identical files when performed on different
2633 machines (@pxref{Invoking guix-daemon, container}).
2636 This foundation allows Guix to support @dfn{transparent binary/source
2637 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2638 available from an external source---a @dfn{substitute}, Guix just
2639 downloads it and unpacks it;
2640 otherwise, it builds the package from source, locally
2641 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2642 reproducible, users do not have to trust servers that provide
2643 substitutes: they can force a local build and @emph{challenge} providers
2644 (@pxref{Invoking guix challenge}).
2646 Control over the build environment is a feature that is also useful for
2647 developers. The @command{guix environment} command allows developers of
2648 a package to quickly set up the right development environment for their
2649 package, without having to manually install the dependencies of the
2650 package into their profile (@pxref{Invoking guix environment}).
2652 @cindex replication, of software environments
2653 @cindex provenance tracking, of software artifacts
2654 All of Guix and its package definitions is version-controlled, and
2655 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2656 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2657 Guix instance on a different machine or at a later point in time, which in
2658 turn allows you to @emph{replicate complete software environments}, while
2659 retaining precise @dfn{provenance tracking} of the software.
2661 @node Invoking guix package
2662 @section Invoking @command{guix package}
2664 @cindex installing packages
2665 @cindex removing packages
2666 @cindex package installation
2667 @cindex package removal
2668 The @command{guix package} command is the tool that allows users to
2669 install, upgrade, and remove packages, as well as rolling back to
2670 previous configurations. It operates only on the user's own profile,
2671 and works with normal user privileges (@pxref{Features}). Its syntax
2675 guix package @var{options}
2678 @cindex transactions
2679 Primarily, @var{options} specifies the operations to be performed during
2680 the transaction. Upon completion, a new profile is created, but
2681 previous @dfn{generations} of the profile remain available, should the user
2684 For example, to remove @code{lua} and install @code{guile} and
2685 @code{guile-cairo} in a single transaction:
2688 guix package -r lua -i guile guile-cairo
2691 @cindex aliases, for @command{guix package}
2692 For your convenience, we also provide the following aliases:
2696 @command{guix search} is an alias for @command{guix package -s},
2698 @command{guix install} is an alias for @command{guix package -i},
2700 @command{guix remove} is an alias for @command{guix package -r},
2702 @command{guix upgrade} is an alias for @command{guix package -u},
2704 and @command{guix show} is an alias for @command{guix package --show=}.
2707 These aliases are less expressive than @command{guix package} and provide
2708 fewer options, so in some cases you'll probably want to use @command{guix
2711 @command{guix package} also supports a @dfn{declarative approach}
2712 whereby the user specifies the exact set of packages to be available and
2713 passes it @i{via} the @option{--manifest} option
2714 (@pxref{profile-manifest, @option{--manifest}}).
2717 For each user, a symlink to the user's default profile is automatically
2718 created in @file{$HOME/.guix-profile}. This symlink always points to the
2719 current generation of the user's default profile. Thus, users can add
2720 @file{$HOME/.guix-profile/bin} to their @code{PATH} environment
2721 variable, and so on.
2722 @cindex search paths
2723 If you are not using Guix System, consider adding the
2724 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
2725 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
2726 shells get all the right environment variable definitions:
2729 GUIX_PROFILE="$HOME/.guix-profile" ; \
2730 source "$HOME/.guix-profile/etc/profile"
2733 In a multi-user setup, user profiles are stored in a place registered as
2734 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
2735 to (@pxref{Invoking guix gc}). That directory is normally
2736 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
2737 @var{localstatedir} is the value passed to @code{configure} as
2738 @code{--localstatedir}, and @var{user} is the user name. The
2739 @file{per-user} directory is created when @command{guix-daemon} is
2740 started, and the @var{user} sub-directory is created by @command{guix
2743 The @var{options} can be among the following:
2747 @item --install=@var{package} @dots{}
2748 @itemx -i @var{package} @dots{}
2749 Install the specified @var{package}s.
2751 Each @var{package} may specify either a simple package name, such as
2752 @code{guile}, or a package name followed by an at-sign and version number,
2753 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
2754 case, the newest version prefixed by @code{1.8} is selected.)
2756 If no version number is specified, the
2757 newest available version will be selected. In addition, @var{package}
2758 may contain a colon, followed by the name of one of the outputs of the
2759 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
2760 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
2761 name (and optionally version) are searched for among the GNU
2762 distribution modules (@pxref{Package Modules}).
2764 @cindex propagated inputs
2765 Sometimes packages have @dfn{propagated inputs}: these are dependencies
2766 that automatically get installed along with the required package
2767 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
2768 @code{package} objects}, for information about propagated inputs in
2769 package definitions).
2771 @anchor{package-cmd-propagated-inputs}
2772 An example is the GNU MPC library: its C header files refer to those of
2773 the GNU MPFR library, which in turn refer to those of the GMP library.
2774 Thus, when installing MPC, the MPFR and GMP libraries also get installed
2775 in the profile; removing MPC also removes MPFR and GMP---unless they had
2776 also been explicitly installed by the user.
2778 Besides, packages sometimes rely on the definition of environment
2779 variables for their search paths (see explanation of
2780 @code{--search-paths} below). Any missing or possibly incorrect
2781 environment variable definitions are reported here.
2783 @item --install-from-expression=@var{exp}
2785 Install the package @var{exp} evaluates to.
2787 @var{exp} must be a Scheme expression that evaluates to a
2788 @code{<package>} object. This option is notably useful to disambiguate
2789 between same-named variants of a package, with expressions such as
2790 @code{(@@ (gnu packages base) guile-final)}.
2792 Note that this option installs the first output of the specified
2793 package, which may be insufficient when needing a specific output of a
2794 multiple-output package.
2796 @item --install-from-file=@var{file}
2797 @itemx -f @var{file}
2798 Install the package that the code within @var{file} evaluates to.
2800 As an example, @var{file} might contain a definition like this
2801 (@pxref{Defining Packages}):
2804 @include package-hello.scm
2807 Developers may find it useful to include such a @file{guix.scm} file
2808 in the root of their project source tree that can be used to test
2809 development snapshots and create reproducible development environments
2810 (@pxref{Invoking guix environment}).
2812 @item --remove=@var{package} @dots{}
2813 @itemx -r @var{package} @dots{}
2814 Remove the specified @var{package}s.
2816 As for @code{--install}, each @var{package} may specify a version number
2817 and/or output name in addition to the package name. For instance,
2818 @code{-r glibc:debug} would remove the @code{debug} output of
2821 @item --upgrade[=@var{regexp} @dots{}]
2822 @itemx -u [@var{regexp} @dots{}]
2823 @cindex upgrading packages
2824 Upgrade all the installed packages. If one or more @var{regexp}s are
2825 specified, upgrade only installed packages whose name matches a
2826 @var{regexp}. Also see the @code{--do-not-upgrade} option below.
2828 Note that this upgrades package to the latest version of packages found
2829 in the distribution currently installed. To update your distribution,
2830 you should regularly run @command{guix pull} (@pxref{Invoking guix
2833 @item --do-not-upgrade[=@var{regexp} @dots{}]
2834 When used together with the @code{--upgrade} option, do @emph{not}
2835 upgrade any packages whose name matches a @var{regexp}. For example, to
2836 upgrade all packages in the current profile except those containing the
2837 substring ``emacs'':
2840 $ guix package --upgrade . --do-not-upgrade emacs
2843 @item @anchor{profile-manifest}--manifest=@var{file}
2844 @itemx -m @var{file}
2845 @cindex profile declaration
2846 @cindex profile manifest
2847 Create a new generation of the profile from the manifest object
2848 returned by the Scheme code in @var{file}. This option can be repeated
2849 several times, in which case the manifests are concatenated.
2851 This allows you to @emph{declare} the profile's contents rather than
2852 constructing it through a sequence of @code{--install} and similar
2853 commands. The advantage is that @var{file} can be put under version
2854 control, copied to different machines to reproduce the same profile, and
2857 @c FIXME: Add reference to (guix profile) documentation when available.
2858 @var{file} must return a @dfn{manifest} object, which is roughly a list
2861 @findex packages->manifest
2863 (use-package-modules guile emacs)
2868 ;; Use a specific package output.
2869 (list guile-2.0 "debug")))
2872 @findex specifications->manifest
2873 In this example we have to know which modules define the @code{emacs}
2874 and @code{guile-2.0} variables to provide the right
2875 @code{use-package-modules} line, which can be cumbersome. We can
2876 instead provide regular package specifications and let
2877 @code{specifications->manifest} look up the corresponding package
2881 (specifications->manifest
2882 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
2886 @cindex rolling back
2887 @cindex undoing transactions
2888 @cindex transactions, undoing
2889 Roll back to the previous @dfn{generation} of the profile---i.e., undo
2890 the last transaction.
2892 When combined with options such as @code{--install}, roll back occurs
2893 before any other actions.
2895 When rolling back from the first generation that actually contains
2896 installed packages, the profile is made to point to the @dfn{zeroth
2897 generation}, which contains no files apart from its own metadata.
2899 After having rolled back, installing, removing, or upgrading packages
2900 overwrites previous future generations. Thus, the history of the
2901 generations in a profile is always linear.
2903 @item --switch-generation=@var{pattern}
2904 @itemx -S @var{pattern}
2906 Switch to a particular generation defined by @var{pattern}.
2908 @var{pattern} may be either a generation number or a number prefixed
2909 with ``+'' or ``-''. The latter means: move forward/backward by a
2910 specified number of generations. For example, if you want to return to
2911 the latest generation after @code{--roll-back}, use
2912 @code{--switch-generation=+1}.
2914 The difference between @code{--roll-back} and
2915 @code{--switch-generation=-1} is that @code{--switch-generation} will
2916 not make a zeroth generation, so if a specified generation does not
2917 exist, the current generation will not be changed.
2919 @item --search-paths[=@var{kind}]
2920 @cindex search paths
2921 Report environment variable definitions, in Bash syntax, that may be
2922 needed in order to use the set of installed packages. These environment
2923 variables are used to specify @dfn{search paths} for files used by some
2924 of the installed packages.
2926 For example, GCC needs the @code{CPATH} and @code{LIBRARY_PATH}
2927 environment variables to be defined so it can look for headers and
2928 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
2929 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
2930 library are installed in the profile, then @code{--search-paths} will
2931 suggest setting these variables to @code{@var{profile}/include} and
2932 @code{@var{profile}/lib}, respectively.
2934 The typical use case is to define these environment variables in the
2938 $ eval `guix package --search-paths`
2941 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
2942 meaning that the returned environment variable definitions will either
2943 be exact settings, or prefixes or suffixes of the current value of these
2944 variables. When omitted, @var{kind} defaults to @code{exact}.
2946 This option can also be used to compute the @emph{combined} search paths
2947 of several profiles. Consider this example:
2950 $ guix package -p foo -i guile
2951 $ guix package -p bar -i guile-json
2952 $ guix package -p foo -p bar --search-paths
2955 The last command above reports about the @code{GUILE_LOAD_PATH}
2956 variable, even though, taken individually, neither @file{foo} nor
2957 @file{bar} would lead to that recommendation.
2960 @item --profile=@var{profile}
2961 @itemx -p @var{profile}
2962 Use @var{profile} instead of the user's default profile.
2964 @var{profile} must be the name of a file that will be created upon
2965 completion. Concretely, @var{profile} will be a mere symbolic link
2966 (``symlink'') pointing to the actual profile where packages are
2970 $ guix install hello -p ~/code/my-profile
2972 $ ~/code/my-profile/bin/hello
2976 All it takes to get rid of the profile is to remove this symlink and its
2977 siblings that point to specific generations:
2980 $ rm ~/code/my-profile ~/code/my-profile-*-link
2983 @item --list-profiles
2984 List all the user's profiles:
2987 $ guix package --list-profiles
2988 /home/charlie/.guix-profile
2989 /home/charlie/code/my-profile
2990 /home/charlie/code/devel-profile
2991 /home/charlie/tmp/test
2994 When running as root, list all the profiles of all the users.
2996 @cindex collisions, in a profile
2997 @cindex colliding packages in profiles
2998 @cindex profile collisions
2999 @item --allow-collisions
3000 Allow colliding packages in the new profile. Use at your own risk!
3002 By default, @command{guix package} reports as an error @dfn{collisions}
3003 in the profile. Collisions happen when two or more different versions
3004 or variants of a given package end up in the profile.
3007 Use the bootstrap Guile to build the profile. This option is only
3008 useful to distribution developers.
3012 In addition to these actions, @command{guix package} supports the
3013 following options to query the current state of a profile, or the
3014 availability of packages:
3018 @item --search=@var{regexp}
3019 @itemx -s @var{regexp}
3020 @cindex searching for packages
3021 List the available packages whose name, synopsis, or description matches
3022 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3023 Print all the metadata of matching packages in
3024 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3025 GNU recutils manual}).
3027 This allows specific fields to be extracted using the @command{recsel}
3028 command, for instance:
3031 $ guix package -s malloc | recsel -p name,version,relevance
3045 Similarly, to show the name of all the packages available under the
3046 terms of the GNU@tie{}LGPL version 3:
3049 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3056 It is also possible to refine search results using several @code{-s} flags to
3057 @command{guix package}, or several arguments to @command{guix search}. For
3058 example, the following command returns a list of board games (this time using
3059 the @command{guix search} alias):
3062 $ guix search '\<board\>' game | recsel -p name
3067 If we were to omit @code{-s game}, we would also get software packages
3068 that deal with printed circuit boards; removing the angle brackets
3069 around @code{board} would further add packages that have to do with
3072 And now for a more elaborate example. The following command searches
3073 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3074 libraries, and prints the name and synopsis of the matching packages:
3077 $ guix search crypto library | \
3078 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3082 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3083 information on @dfn{selection expressions} for @code{recsel -e}.
3085 @item --show=@var{package}
3086 Show details about @var{package}, taken from the list of available packages, in
3087 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3091 $ guix package --show=python | recsel -p name,version
3099 You may also specify the full name of a package to only get details about a
3100 specific version of it (this time using the @command{guix show} alias):
3102 $ guix show python@@3.4 | recsel -p name,version
3109 @item --list-installed[=@var{regexp}]
3110 @itemx -I [@var{regexp}]
3111 List the currently installed packages in the specified profile, with the
3112 most recently installed packages shown last. When @var{regexp} is
3113 specified, list only installed packages whose name matches @var{regexp}.
3115 For each installed package, print the following items, separated by
3116 tabs: the package name, its version string, the part of the package that
3117 is installed (for instance, @code{out} for the default output,
3118 @code{include} for its headers, etc.), and the path of this package in
3121 @item --list-available[=@var{regexp}]
3122 @itemx -A [@var{regexp}]
3123 List packages currently available in the distribution for this system
3124 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3125 installed packages whose name matches @var{regexp}.
3127 For each package, print the following items separated by tabs: its name,
3128 its version string, the parts of the package (@pxref{Packages with
3129 Multiple Outputs}), and the source location of its definition.
3131 @item --list-generations[=@var{pattern}]
3132 @itemx -l [@var{pattern}]
3134 Return a list of generations along with their creation dates; for each
3135 generation, show the installed packages, with the most recently
3136 installed packages shown last. Note that the zeroth generation is never
3139 For each installed package, print the following items, separated by
3140 tabs: the name of a package, its version string, the part of the package
3141 that is installed (@pxref{Packages with Multiple Outputs}), and the
3142 location of this package in the store.
3144 When @var{pattern} is used, the command returns only matching
3145 generations. Valid patterns include:
3148 @item @emph{Integers and comma-separated integers}. Both patterns denote
3149 generation numbers. For instance, @code{--list-generations=1} returns
3152 And @code{--list-generations=1,8,2} outputs three generations in the
3153 specified order. Neither spaces nor trailing commas are allowed.
3155 @item @emph{Ranges}. @code{--list-generations=2..9} prints the
3156 specified generations and everything in between. Note that the start of
3157 a range must be smaller than its end.
3159 It is also possible to omit the endpoint. For example,
3160 @code{--list-generations=2..}, returns all generations starting from the
3163 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3164 or months by passing an integer along with the first letter of the
3165 duration. For example, @code{--list-generations=20d} lists generations
3166 that are up to 20 days old.
3169 @item --delete-generations[=@var{pattern}]
3170 @itemx -d [@var{pattern}]
3171 When @var{pattern} is omitted, delete all generations except the current
3174 This command accepts the same patterns as @option{--list-generations}.
3175 When @var{pattern} is specified, delete the matching generations. When
3176 @var{pattern} specifies a duration, generations @emph{older} than the
3177 specified duration match. For instance, @code{--delete-generations=1m}
3178 deletes generations that are more than one month old.
3180 If the current generation matches, it is @emph{not} deleted. Also, the
3181 zeroth generation is never deleted.
3183 Note that deleting generations prevents rolling back to them.
3184 Consequently, this command must be used with care.
3188 Finally, since @command{guix package} may actually start build
3189 processes, it supports all the common build options (@pxref{Common Build
3190 Options}). It also supports package transformation options, such as
3191 @option{--with-source} (@pxref{Package Transformation Options}).
3192 However, note that package transformations are lost when upgrading; to
3193 preserve transformations across upgrades, you should define your own
3194 package variant in a Guile module and add it to @code{GUIX_PACKAGE_PATH}
3195 (@pxref{Defining Packages}).
3198 @section Substitutes
3201 @cindex pre-built binaries
3202 Guix supports transparent source/binary deployment, which means that it
3203 can either build things locally, or download pre-built items from a
3204 server, or both. We call these pre-built items @dfn{substitutes}---they
3205 are substitutes for local build results. In many cases, downloading a
3206 substitute is much faster than building things locally.
3208 Substitutes can be anything resulting from a derivation build
3209 (@pxref{Derivations}). Of course, in the common case, they are
3210 pre-built package binaries, but source tarballs, for instance, which
3211 also result from derivation builds, can be available as substitutes.
3214 * Official Substitute Server:: One particular source of substitutes.
3215 * Substitute Server Authorization:: How to enable or disable substitutes.
3216 * Substitute Authentication:: How Guix verifies substitutes.
3217 * Proxy Settings:: How to get substitutes via proxy.
3218 * Substitution Failure:: What happens when substitution fails.
3219 * On Trusting Binaries:: How can you trust that binary blob?
3222 @node Official Substitute Server
3223 @subsection Official Substitute Server
3226 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3227 that builds packages from Guix continuously for some
3228 architectures, and makes them available as substitutes. This is the
3229 default source of substitutes; it can be overridden by passing the
3230 @option{--substitute-urls} option either to @command{guix-daemon}
3231 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3232 or to client tools such as @command{guix package}
3233 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3236 Substitute URLs can be either HTTP or HTTPS.
3237 HTTPS is recommended because communications are encrypted; conversely,
3238 using HTTP makes all communications visible to an eavesdropper, who
3239 could use the information gathered to determine, for instance, whether
3240 your system has unpatched security vulnerabilities.
3242 Substitutes from the official build farm are enabled by default when
3243 using Guix System (@pxref{GNU Distribution}). However,
3244 they are disabled by default when using Guix on a foreign distribution,
3245 unless you have explicitly enabled them via one of the recommended
3246 installation steps (@pxref{Installation}). The following paragraphs
3247 describe how to enable or disable substitutes for the official build
3248 farm; the same procedure can also be used to enable substitutes for any
3249 other substitute server.
3251 @node Substitute Server Authorization
3252 @subsection Substitute Server Authorization
3255 @cindex substitutes, authorization thereof
3256 @cindex access control list (ACL), for substitutes
3257 @cindex ACL (access control list), for substitutes
3258 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3260 must add its public key to the access control list (ACL) of archive
3261 imports, using the @command{guix archive} command (@pxref{Invoking guix
3262 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3263 be compromised and to serve genuine substitutes.
3265 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3266 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3267 the installation prefix of Guix. If you installed Guix from source,
3268 make sure you checked the GPG signature of
3269 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3270 Then, you can run something like this:
3273 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3276 Once this is in place, the output of a command like @code{guix build}
3277 should change from something like:
3280 $ guix build emacs --dry-run
3281 The following derivations would be built:
3282 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3283 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3284 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3285 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3293 $ guix build emacs --dry-run
3294 112.3 MB would be downloaded:
3295 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3296 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3297 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3298 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3303 The text changed from ``The following derivations would be built'' to
3304 ``112.3 MB would be downloaded''. This indicates that substitutes from
3305 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3306 possible, for future builds.
3308 @cindex substitutes, how to disable
3309 The substitute mechanism can be disabled globally by running
3310 @code{guix-daemon} with @code{--no-substitutes} (@pxref{Invoking
3311 guix-daemon}). It can also be disabled temporarily by passing the
3312 @code{--no-substitutes} option to @command{guix package}, @command{guix
3313 build}, and other command-line tools.
3315 @node Substitute Authentication
3316 @subsection Substitute Authentication
3318 @cindex digital signatures
3319 Guix detects and raises an error when attempting to use a substitute
3320 that has been tampered with. Likewise, it ignores substitutes that are
3321 not signed, or that are not signed by one of the keys listed in the ACL.
3323 There is one exception though: if an unauthorized server provides
3324 substitutes that are @emph{bit-for-bit identical} to those provided by
3325 an authorized server, then the unauthorized server becomes eligible for
3326 downloads. For example, assume we have chosen two substitute servers
3330 --substitute-urls="https://a.example.org https://b.example.org"
3334 @cindex reproducible builds
3335 If the ACL contains only the key for @code{b.example.org}, and if
3336 @code{a.example.org} happens to serve the @emph{exact same} substitutes,
3337 then Guix will download substitutes from @code{a.example.org} because it
3338 comes first in the list and can be considered a mirror of
3339 @code{b.example.org}. In practice, independent build machines usually
3340 produce the same binaries, thanks to bit-reproducible builds (see
3343 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3344 (in other words, the server is not authenticated), contrary to what
3345 HTTPS clients such as Web browsers usually do. This is because Guix
3346 authenticates substitute information itself, as explained above, which
3347 is what we care about (whereas X.509 certificates are about
3348 authenticating bindings between domain names and public keys.)
3350 @node Proxy Settings
3351 @subsection Proxy Settings
3354 Substitutes are downloaded over HTTP or HTTPS.
3355 The @code{http_proxy} environment
3356 variable can be set in the environment of @command{guix-daemon} and is
3357 honored for downloads of substitutes. Note that the value of
3358 @code{http_proxy} in the environment where @command{guix build},
3359 @command{guix package}, and other client commands are run has
3360 @emph{absolutely no effect}.
3362 @node Substitution Failure
3363 @subsection Substitution Failure
3365 Even when a substitute for a derivation is available, sometimes the
3366 substitution attempt will fail. This can happen for a variety of
3367 reasons: the substitute server might be offline, the substitute may
3368 recently have been deleted, the connection might have been interrupted,
3371 When substitutes are enabled and a substitute for a derivation is
3372 available, but the substitution attempt fails, Guix will attempt to
3373 build the derivation locally depending on whether or not
3374 @code{--fallback} was given (@pxref{fallback-option,, common build
3375 option @code{--fallback}}). Specifically, if @code{--fallback} was
3376 omitted, then no local build will be performed, and the derivation is
3377 considered to have failed. However, if @code{--fallback} was given,
3378 then Guix will attempt to build the derivation locally, and the success
3379 or failure of the derivation depends on the success or failure of the
3380 local build. Note that when substitutes are disabled or no substitute
3381 is available for the derivation in question, a local build will
3382 @emph{always} be performed, regardless of whether or not
3383 @code{--fallback} was given.
3385 To get an idea of how many substitutes are available right now, you can
3386 try running the @command{guix weather} command (@pxref{Invoking guix
3387 weather}). This command provides statistics on the substitutes provided
3390 @node On Trusting Binaries
3391 @subsection On Trusting Binaries
3393 @cindex trust, of pre-built binaries
3394 Today, each individual's control over their own computing is at the
3395 mercy of institutions, corporations, and groups with enough power and
3396 determination to subvert the computing infrastructure and exploit its
3397 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3398 convenient, we encourage users to also build on their own, or even run
3399 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3400 interesting target. One way to help is by publishing the software you
3401 build using @command{guix publish} so that others have one more choice
3402 of server to download substitutes from (@pxref{Invoking guix publish}).
3404 Guix has the foundations to maximize build reproducibility
3405 (@pxref{Features}). In most cases, independent builds of a given
3406 package or derivation should yield bit-identical results. Thus, through
3407 a diverse set of independent package builds, we can strengthen the
3408 integrity of our systems. The @command{guix challenge} command aims to
3409 help users assess substitute servers, and to assist developers in
3410 finding out about non-deterministic package builds (@pxref{Invoking guix
3411 challenge}). Similarly, the @option{--check} option of @command{guix
3412 build} allows users to check whether previously-installed substitutes
3413 are genuine by rebuilding them locally (@pxref{build-check,
3414 @command{guix build --check}}).
3416 In the future, we want Guix to have support to publish and retrieve
3417 binaries to/from other users, in a peer-to-peer fashion. If you would
3418 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3420 @node Packages with Multiple Outputs
3421 @section Packages with Multiple Outputs
3423 @cindex multiple-output packages
3424 @cindex package outputs
3427 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3428 source package leads to exactly one directory in the store. When running
3429 @command{guix install glibc}, one installs the default output of the
3430 GNU libc package; the default output is called @code{out}, but its name
3431 can be omitted as shown in this command. In this particular case, the
3432 default output of @code{glibc} contains all the C header files, shared
3433 libraries, static libraries, Info documentation, and other supporting
3436 Sometimes it is more appropriate to separate the various types of files
3437 produced from a single source package into separate outputs. For
3438 instance, the GLib C library (used by GTK+ and related packages)
3439 installs more than 20 MiB of reference documentation as HTML pages.
3440 To save space for users who do not need it, the documentation goes to a
3441 separate output, called @code{doc}. To install the main GLib output,
3442 which contains everything but the documentation, one would run:
3448 @cindex documentation
3449 The command to install its documentation is:
3452 guix install glib:doc
3455 Some packages install programs with different ``dependency footprints''.
3456 For instance, the WordNet package installs both command-line tools and
3457 graphical user interfaces (GUIs). The former depend solely on the C
3458 library, whereas the latter depend on Tcl/Tk and the underlying X
3459 libraries. In this case, we leave the command-line tools in the default
3460 output, whereas the GUIs are in a separate output. This allows users
3461 who do not need the GUIs to save space. The @command{guix size} command
3462 can help find out about such situations (@pxref{Invoking guix size}).
3463 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3465 There are several such multiple-output packages in the GNU distribution.
3466 Other conventional output names include @code{lib} for libraries and
3467 possibly header files, @code{bin} for stand-alone programs, and
3468 @code{debug} for debugging information (@pxref{Installing Debugging
3469 Files}). The outputs of a packages are listed in the third column of
3470 the output of @command{guix package --list-available} (@pxref{Invoking
3474 @node Invoking guix gc
3475 @section Invoking @command{guix gc}
3477 @cindex garbage collector
3479 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3480 The @command{guix gc} command allows users to explicitly run the garbage
3481 collector to reclaim space from the @file{/gnu/store} directory. It is
3482 the @emph{only} way to remove files from @file{/gnu/store}---removing
3483 files or directories manually may break it beyond repair!
3486 @cindex garbage collector roots
3487 The garbage collector has a set of known @dfn{roots}: any file under
3488 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3489 cannot be deleted; any other file is considered @dfn{dead} and may be
3490 deleted. The set of garbage collector roots (``GC roots'' for short)
3491 includes default user profiles; by default, the symlinks under
3492 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3493 added with @command{guix build --root}, for example (@pxref{Invoking
3494 guix build}). The @command{guix gc --list-roots} command lists them.
3496 Prior to running @code{guix gc --collect-garbage} to make space, it is
3497 often useful to remove old generations from user profiles; that way, old
3498 package builds referenced by those generations can be reclaimed. This
3499 is achieved by running @code{guix package --delete-generations}
3500 (@pxref{Invoking guix package}).
3502 Our recommendation is to run a garbage collection periodically, or when
3503 you are short on disk space. For instance, to guarantee that at least
3504 5@tie{}GB are available on your disk, simply run:
3510 It is perfectly safe to run as a non-interactive periodic job
3511 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3512 Running @command{guix gc} with no arguments will collect as
3513 much garbage as it can, but that is often inconvenient: you may find
3514 yourself having to rebuild or re-download software that is ``dead'' from
3515 the GC viewpoint but that is necessary to build other pieces of
3516 software---e.g., the compiler tool chain.
3518 The @command{guix gc} command has three modes of operation: it can be
3519 used to garbage-collect any dead files (the default), to delete specific
3520 files (the @code{--delete} option), to print garbage-collector
3521 information, or for more advanced queries. The garbage collection
3522 options are as follows:
3525 @item --collect-garbage[=@var{min}]
3526 @itemx -C [@var{min}]
3527 Collect garbage---i.e., unreachable @file{/gnu/store} files and
3528 sub-directories. This is the default operation when no option is
3531 When @var{min} is given, stop once @var{min} bytes have been collected.
3532 @var{min} may be a number of bytes, or it may include a unit as a
3533 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
3534 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
3536 When @var{min} is omitted, collect all the garbage.
3538 @item --free-space=@var{free}
3539 @itemx -F @var{free}
3540 Collect garbage until @var{free} space is available under
3541 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
3542 as @code{500MiB}, as described above.
3544 When @var{free} or more is already available in @file{/gnu/store}, do
3545 nothing and exit immediately.
3547 @item --delete-generations[=@var{duration}]
3548 @itemx -d [@var{duration}]
3549 Before starting the garbage collection process, delete all the generations
3550 older than @var{duration}, for all the user profiles; when run as root, this
3551 applies to all the profiles @emph{of all the users}.
3553 For example, this command deletes all the generations of all your profiles
3554 that are older than 2 months (except generations that are current), and then
3555 proceeds to free space until at least 10 GiB are available:
3558 guix gc -d 2m -F 10G
3563 Attempt to delete all the store files and directories specified as
3564 arguments. This fails if some of the files are not in the store, or if
3565 they are still live.
3567 @item --list-failures
3568 List store items corresponding to cached build failures.
3570 This prints nothing unless the daemon was started with
3571 @option{--cache-failures} (@pxref{Invoking guix-daemon,
3572 @option{--cache-failures}}).
3575 List the GC roots owned by the user; when run as root, list @emph{all} the GC
3579 List store items in use by currently running processes. These store
3580 items are effectively considered GC roots: they cannot be deleted.
3582 @item --clear-failures
3583 Remove the specified store items from the failed-build cache.
3585 Again, this option only makes sense when the daemon is started with
3586 @option{--cache-failures}. Otherwise, it does nothing.
3589 Show the list of dead files and directories still present in the
3590 store---i.e., files and directories no longer reachable from any root.
3593 Show the list of live store files and directories.
3597 In addition, the references among existing store files can be queried:
3603 @cindex package dependencies
3604 List the references (respectively, the referrers) of store files given
3610 List the requisites of the store files passed as arguments. Requisites
3611 include the store files themselves, their references, and the references
3612 of these, recursively. In other words, the returned list is the
3613 @dfn{transitive closure} of the store files.
3615 @xref{Invoking guix size}, for a tool to profile the size of the closure
3616 of an element. @xref{Invoking guix graph}, for a tool to visualize
3617 the graph of references.
3621 Return the derivation(s) leading to the given store items
3622 (@pxref{Derivations}).
3624 For example, this command:
3627 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
3631 returns the @file{.drv} file(s) leading to the @code{emacs} package
3632 installed in your profile.
3634 Note that there may be zero matching @file{.drv} files, for instance
3635 because these files have been garbage-collected. There can also be more
3636 than one matching @file{.drv} due to fixed-output derivations.
3639 Lastly, the following options allow you to check the integrity of the
3640 store and to control disk usage.
3644 @item --verify[=@var{options}]
3645 @cindex integrity, of the store
3646 @cindex integrity checking
3647 Verify the integrity of the store.
3649 By default, make sure that all the store items marked as valid in the
3650 database of the daemon actually exist in @file{/gnu/store}.
3652 When provided, @var{options} must be a comma-separated list containing one
3653 or more of @code{contents} and @code{repair}.
3655 When passing @option{--verify=contents}, the daemon computes the
3656 content hash of each store item and compares it against its hash in the
3657 database. Hash mismatches are reported as data corruptions. Because it
3658 traverses @emph{all the files in the store}, this command can take a
3659 long time, especially on systems with a slow disk drive.
3661 @cindex repairing the store
3662 @cindex corruption, recovering from
3663 Using @option{--verify=repair} or @option{--verify=contents,repair}
3664 causes the daemon to try to repair corrupt store items by fetching
3665 substitutes for them (@pxref{Substitutes}). Because repairing is not
3666 atomic, and thus potentially dangerous, it is available only to the
3667 system administrator. A lightweight alternative, when you know exactly
3668 which items in the store are corrupt, is @command{guix build --repair}
3669 (@pxref{Invoking guix build}).
3672 @cindex deduplication
3673 Optimize the store by hard-linking identical files---this is
3674 @dfn{deduplication}.
3676 The daemon performs deduplication after each successful build or archive
3677 import, unless it was started with @code{--disable-deduplication}
3678 (@pxref{Invoking guix-daemon, @code{--disable-deduplication}}). Thus,
3679 this option is primarily useful when the daemon was running with
3680 @code{--disable-deduplication}.
3684 @node Invoking guix pull
3685 @section Invoking @command{guix pull}
3687 @cindex upgrading Guix
3688 @cindex updating Guix
3689 @cindex @command{guix pull}
3691 Packages are installed or upgraded to the latest version available in
3692 the distribution currently available on your local machine. To update
3693 that distribution, along with the Guix tools, you must run @command{guix
3694 pull}: the command downloads the latest Guix source code and package
3695 descriptions, and deploys it. Source code is downloaded from a
3696 @uref{https://git-scm.com, Git} repository, by default the official
3697 GNU@tie{}Guix repository, though this can be customized.
3699 Specifically, @command{guix pull} downloads code from the @dfn{channels}
3700 (@pxref{Channels}) specified by one of the followings, in this order:
3704 the @option{--channels} option;
3706 the user's @file{~/.config/guix/channels.scm} file;
3708 the system-wide @file{/etc/guix/channels.scm} file;
3710 the built-in default channels specified in the @code{%default-channels}
3714 On completion, @command{guix package} will use packages and package
3715 versions from this just-retrieved copy of Guix. Not only that, but all
3716 the Guix commands and Scheme modules will also be taken from that latest
3717 version. New @command{guix} sub-commands added by the update also
3720 Any user can update their Guix copy using @command{guix pull}, and the
3721 effect is limited to the user who ran @command{guix pull}. For
3722 instance, when user @code{root} runs @command{guix pull}, this has no
3723 effect on the version of Guix that user @code{alice} sees, and vice
3726 The result of running @command{guix pull} is a @dfn{profile} available
3727 under @file{~/.config/guix/current} containing the latest Guix. Thus,
3728 make sure to add it to the beginning of your search path so that you use
3729 the latest version, and similarly for the Info manual
3730 (@pxref{Documentation}):
3733 export PATH="$HOME/.config/guix/current/bin:$PATH"
3734 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
3737 The @code{--list-generations} or @code{-l} option lists past generations
3738 produced by @command{guix pull}, along with details about their provenance:
3742 Generation 1 Jun 10 2018 00:18:18
3744 repository URL: https://git.savannah.gnu.org/git/guix.git
3745 branch: origin/master
3746 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
3748 Generation 2 Jun 11 2018 11:02:49
3750 repository URL: https://git.savannah.gnu.org/git/guix.git
3751 branch: origin/master
3752 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
3753 2 new packages: keepalived, libnfnetlink
3754 6 packages upgraded: emacs-nix-mode@@2.0.4,
3755 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
3756 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
3758 Generation 3 Jun 13 2018 23:31:07 (current)
3760 repository URL: https://git.savannah.gnu.org/git/guix.git
3761 branch: origin/master
3762 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
3763 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
3764 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
3767 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
3768 describe the current status of Guix.
3770 This @code{~/.config/guix/current} profile works exactly like the profiles
3771 created by @command{guix package} (@pxref{Invoking guix package}). That
3772 is, you can list generations, roll back to the previous
3773 generation---i.e., the previous Guix---and so on:
3776 $ guix pull --roll-back
3777 switched from generation 3 to 2
3778 $ guix pull --delete-generations=1
3779 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3782 You can also use @command{guix package} (@pxref{Invoking guix package})
3783 to manage the profile by naming it explicitly:
3785 $ guix package -p ~/.config/guix/current --roll-back
3786 switched from generation 3 to 2
3787 $ guix package -p ~/.config/guix/current --delete-generations=1
3788 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
3791 The @command{guix pull} command is usually invoked with no arguments,
3792 but it supports the following options:
3795 @item --url=@var{url}
3796 @itemx --commit=@var{commit}
3797 @itemx --branch=@var{branch}
3798 Download code for the @code{guix} channel from the specified @var{url}, at the
3799 given @var{commit} (a valid Git commit ID represented as a hexadecimal
3800 string), or @var{branch}.
3802 @cindex @file{channels.scm}, configuration file
3803 @cindex configuration file for channels
3804 These options are provided for convenience, but you can also specify your
3805 configuration in the @file{~/.config/guix/channels.scm} file or using the
3806 @option{--channels} option (see below).
3808 @item --channels=@var{file}
3809 @itemx -C @var{file}
3810 Read the list of channels from @var{file} instead of
3811 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
3812 @var{file} must contain Scheme code that
3813 evaluates to a list of channel objects. @xref{Channels}, for more
3816 @cindex channel news
3819 Display the list of packages added or upgraded since the previous
3820 generation, as well as, occasionally, news written by channel authors
3821 for their users (@pxref{Channels, Writing Channel News}).
3823 The package information is the same as displayed upon @command{guix
3824 pull} completion, but without ellipses; it is also similar to the output
3825 of @command{guix pull -l} for the last generation (see below).
3827 @item --list-generations[=@var{pattern}]
3828 @itemx -l [@var{pattern}]
3829 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
3830 is provided, the subset of generations that match @var{pattern}.
3831 The syntax of @var{pattern} is the same as with @code{guix package
3832 --list-generations} (@pxref{Invoking guix package}).
3835 @cindex rolling back
3836 @cindex undoing transactions
3837 @cindex transactions, undoing
3838 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
3839 undo the last transaction.
3841 @item --switch-generation=@var{pattern}
3842 @itemx -S @var{pattern}
3844 Switch to a particular generation defined by @var{pattern}.
3846 @var{pattern} may be either a generation number or a number prefixed
3847 with ``+'' or ``-''. The latter means: move forward/backward by a
3848 specified number of generations. For example, if you want to return to
3849 the latest generation after @code{--roll-back}, use
3850 @code{--switch-generation=+1}.
3852 @item --delete-generations[=@var{pattern}]
3853 @itemx -d [@var{pattern}]
3854 When @var{pattern} is omitted, delete all generations except the current
3857 This command accepts the same patterns as @option{--list-generations}.
3858 When @var{pattern} is specified, delete the matching generations. When
3859 @var{pattern} specifies a duration, generations @emph{older} than the
3860 specified duration match. For instance, @code{--delete-generations=1m}
3861 deletes generations that are more than one month old.
3863 If the current generation matches, it is @emph{not} deleted.
3865 Note that deleting generations prevents rolling back to them.
3866 Consequently, this command must be used with care.
3868 @xref{Invoking guix describe}, for a way to display information about the
3869 current generation only.
3871 @item --profile=@var{profile}
3872 @itemx -p @var{profile}
3873 Use @var{profile} instead of @file{~/.config/guix/current}.
3877 Show which channel commit(s) would be used and what would be built or
3878 substituted but do not actually do it.
3880 @item --system=@var{system}
3881 @itemx -s @var{system}
3882 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
3883 the system type of the build host.
3886 Produce verbose output, writing build logs to the standard error output.
3889 Use the bootstrap Guile to build the latest Guix. This option is only
3890 useful to Guix developers.
3893 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
3894 repository and branch to pull from, as well as @emph{additional} repositories
3895 containing package modules that should be deployed. @xref{Channels}, for more
3898 In addition, @command{guix pull} supports all the common build options
3899 (@pxref{Common Build Options}).
3905 @cindex @file{channels.scm}, configuration file
3906 @cindex configuration file for channels
3907 @cindex @command{guix pull}, configuration file
3908 @cindex configuration of @command{guix pull}
3909 Guix and its package collection are updated by running @command{guix pull}
3910 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
3911 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
3912 customized by defining @dfn{channels} in the
3913 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
3914 of a Git repository to be deployed, and @command{guix pull} can be instructed
3915 to pull from one or more channels. In other words, channels can be used to
3916 @emph{customize} and to @emph{extend} Guix, as we will see below.
3918 @subsection Using a Custom Guix Channel
3920 The channel called @code{guix} specifies where Guix itself---its command-line
3921 tools as well as its package collection---should be downloaded. For instance,
3922 suppose you want to update from your own copy of the Guix repository at
3923 @code{example.org}, and specifically the @code{super-hacks} branch, you can
3924 write in @code{~/.config/guix/channels.scm} this specification:
3927 ;; Tell 'guix pull' to use my own repo.
3930 (url "https://example.org/my-guix.git")
3931 (branch "super-hacks")))
3935 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
3936 branch of the repository at @code{example.org}.
3938 @subsection Specifying Additional Channels
3940 @cindex extending the package collection (channels)
3941 @cindex personal packages (channels)
3942 @cindex channels, for personal packages
3943 You can also specify @emph{additional channels} to pull from. Let's say you
3944 have a bunch of custom package variants or personal packages that you think
3945 would make little sense to contribute to the Guix project, but would like to
3946 have these packages transparently available to you at the command line. You
3947 would first write modules containing those package definitions (@pxref{Package
3948 Modules}), maintain them in a Git repository, and then you and anyone else can
3949 use it as an additional channel to get packages from. Neat, no?
3951 @c What follows stems from discussions at
3952 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
3953 @c earlier discussions on guix-devel@gnu.org.
3955 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
3956 publish your personal channel to the world, we would like to share a few words
3961 Before publishing a channel, please consider contributing your package
3962 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
3963 to free software of all sorts, and packages in Guix proper are readily
3964 available to all Guix users and benefit from the project's quality assurance
3968 When you maintain package definitions outside Guix, we, Guix developers,
3969 consider that @emph{the compatibility burden is on you}. Remember that
3970 package modules and package definitions are just Scheme code that uses various
3971 programming interfaces (APIs). We want to remain free to change these APIs to
3972 keep improving Guix, possibly in ways that break your channel. We never
3973 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
3977 Corollary: if you're using an external channel and that channel breaks, please
3978 @emph{report the issue to the channel authors}, not to the Guix project.
3981 You've been warned! Having said this, we believe external channels are a
3982 practical way to exert your freedom to augment Guix' package collection and to
3983 share your improvements, which are basic tenets of
3984 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
3985 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
3988 To use a channel, write @code{~/.config/guix/channels.scm} to instruct
3989 @command{guix pull} to pull from it @emph{in addition} to the default Guix
3992 @vindex %default-channels
3994 ;; Add my personal packages to those Guix provides.
3996 (name 'my-personal-packages)
3997 (url "https://example.org/personal-packages.git"))
4002 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4003 add a channel the list of channels that the variable @code{%default-channels}
4004 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4005 Manual}). With this file in place, @command{guix pull} builds not only Guix
4006 but also the package modules from your own repository. The result in
4007 @file{~/.config/guix/current} is the union of Guix with your own package
4011 $ guix pull --list-generations
4013 Generation 19 Aug 27 2018 16:20:48
4015 repository URL: https://git.savannah.gnu.org/git/guix.git
4017 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4018 my-personal-packages dd3df5e
4019 repository URL: https://example.org/personal-packages.git
4021 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4022 11 new packages: my-gimp, my-emacs-with-cool-features, @dots{}
4023 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4027 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4028 both Guix and packages from the @code{my-personal-packages} channel. Among
4029 the new and upgraded packages that are listed, some like @code{my-gimp} and
4030 @code{my-emacs-with-cool-features} might come from
4031 @code{my-personal-packages}, while others come from the Guix default channel.
4033 To create a channel, create a Git repository containing your own package
4034 modules and make it available. The repository can contain anything, but a
4035 useful channel will contain Guile modules that export packages. Once you
4036 start using a channel, Guix will behave as if the root directory of that
4037 channel's Git repository has been added to the Guile load path (@pxref{Load
4038 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
4039 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
4040 module, then the module will be available under the name @code{(my-packages
4041 my-tools)}, and you will be able to use it like any other module
4042 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
4044 @cindex dependencies, channels
4045 @cindex meta-data, channels
4046 @subsection Declaring Channel Dependencies
4048 Channel authors may decide to augment a package collection provided by other
4049 channels. They can declare their channel to be dependent on other channels in
4050 a meta-data file @file{.guix-channel}, which is to be placed in the root of
4051 the channel repository.
4053 The meta-data file should contain a simple S-expression like this:
4060 (name some-collection)
4061 (url "https://example.org/first-collection.git"))
4063 (name some-other-collection)
4064 (url "https://example.org/second-collection.git")
4065 (branch "testing"))))
4068 In the above example this channel is declared to depend on two other channels,
4069 which will both be fetched automatically. The modules provided by the channel
4070 will be compiled in an environment where the modules of all these declared
4071 channels are available.
4073 For the sake of reliability and maintainability, you should avoid dependencies
4074 on channels that you don't control, and you should aim to keep the number of
4075 dependencies to a minimum.
4077 @cindex subdirectory, channels
4078 @subsection Package Modules in a Sub-directory
4080 As a channel author, you may want to keep your channel modules in a
4081 sub-directory. If your modules are in the sub-directory @file{guix}, you must
4082 add a meta-data file @file{.guix-channel} that contains:
4090 @cindex news, for channels
4091 @subsection Writing Channel News
4093 Channel authors may occasionally want to communicate to their users
4094 information about important changes in the channel. You'd send them all
4095 an email, but that's not convenient.
4097 Instead, channels can provide a @dfn{news file}; when the channel users
4098 run @command{guix pull}, that news file is automatically read and
4099 @command{guix pull --news} can display the announcements that correspond
4100 to the new commits that have been pulled, if any.
4102 To do that, channel authors must first declare the name of the news file
4103 in their @file{.guix-channel} file:
4108 (news-file "etc/news.txt"))
4111 The news file itself, @file{etc/news.txt} in this example, must look
4112 something like this:
4117 (entry (tag "the-bug-fix")
4118 (title (en "Fixed terrible bug")
4120 (body (en "@@emph@{Good news@}! It's fixed!")
4121 (eo "Certe ĝi pli bone funkcias nun!")))
4122 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
4123 (title (en "Added a great package")
4124 (ca "Què vol dir guix?"))
4125 (body (en "Don't miss the @@code@{hello@} package!"))))
4128 The file consists of a list of @dfn{news entries}. Each entry is
4129 associated with a commit or tag: it describes changes made in this
4130 commit, possibly in preceding commits as well. Users see entries only
4131 the first time they obtain the commit the entry refers to.
4133 The @code{title} field should be a one-line summary while @code{body}
4134 can be arbitrarily long, and both can contain Texinfo markup
4135 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
4136 a list of language tag/message tuples, which allows @command{guix pull}
4137 to display news in the language that corresponds to the user's locale.
4139 If you want to translate news using a gettext-based workflow, you can
4140 extract translatable strings with @command{xgettext} (@pxref{xgettext
4141 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
4142 you write news entries in English first, the command below creates a PO
4143 file containing the strings to translate:
4146 xgettext -o news.po -l scheme -ken etc/news.scm
4149 To sum up, yes, you could use your channel as a blog. But beware, this
4150 is @emph{not quite} what your users might expect.
4152 @subsection Replicating Guix
4154 @cindex pinning, channels
4155 @cindex replicating Guix
4156 @cindex reproducibility, of Guix
4157 The @command{guix pull --list-generations} output above shows precisely which
4158 commits were used to build this instance of Guix. We can thus replicate it,
4159 say, on another machine, by providing a channel specification in
4160 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4163 ;; Deploy specific commits of my channels of interest.
4166 (url "https://git.savannah.gnu.org/git/guix.git")
4167 (commit "d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300"))
4169 (name 'my-personal-packages)
4170 (url "https://example.org/personal-packages.git")
4171 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
4174 The @command{guix describe --format=channels} command can even generate this
4175 list of channels directly (@pxref{Invoking guix describe}). The resulting
4176 file can be used with the -C options of @command{guix pull}
4177 (@pxref{Invoking guix pull}) or @command{guix time-machine}
4178 (@pxref{Invoking guix time-machine}).
4180 At this point the two machines run the @emph{exact same Guix}, with access to
4181 the @emph{exact same packages}. The output of @command{guix build gimp} on
4182 one machine will be exactly the same, bit for bit, as the output of the same
4183 command on the other machine. It also means both machines have access to all
4184 the source code of Guix and, transitively, to all the source code of every
4187 This gives you super powers, allowing you to track the provenance of binary
4188 artifacts with very fine grain, and to reproduce software environments at
4189 will---some sort of ``meta reproducibility'' capabilities, if you will.
4190 @xref{Inferiors}, for another way to take advantage of these super powers.
4192 @node Invoking guix time-machine
4193 @section Invoking @command{guix time-machine}
4195 @cindex @command{guix time-machine}
4196 @cindex pinning, channels
4197 @cindex replicating Guix
4198 @cindex reproducibility, of Guix
4200 The @command{guix time-machine} command provides access to other
4201 revisions of Guix, for example to install older versions of packages,
4202 or to reproduce a computation in an identical environment. The revision
4203 of Guix to be used is defined by a commit or by a channel
4204 description file created by @command{guix describe}
4205 (@pxref{Invoking guix describe}).
4207 The general syntax is:
4210 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4213 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4214 @command{guix} command if the specified revision. The @var{options} that define
4215 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4218 @item --url=@var{url}
4219 @itemx --commit=@var{commit}
4220 @itemx --branch=@var{branch}
4221 Use the @code{guix} channel from the specified @var{url}, at the
4222 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4223 string), or @var{branch}.
4225 @item --channels=@var{file}
4226 @itemx -C @var{file}
4227 Read the list of channels from @var{file}. @var{file} must contain
4228 Scheme code that evaluates to a list of channel objects.
4229 @xref{Channels} for more information.
4232 As for @command{guix pull}, the absence of any options means that the
4233 the latest commit on the master branch will be used. The command
4236 guix time-machine -- build hello
4239 will thus build the package @code{hello} as defined in the master branch,
4240 which is in general a newer revision of Guix than you have installed.
4241 Time travel works in both directions!
4243 Note that @command{guix time-machine} can trigger builds of channels and
4244 their dependencies, and these are controlled by the standard build
4245 options (@pxref{Common Build Options}).
4250 @c TODO: Remove this once we're more confident about API stability.
4252 The functionality described here is a ``technology preview'' as of version
4253 @value{VERSION}. As such, the interface is subject to change.
4257 @cindex composition of Guix revisions
4258 Sometimes you might need to mix packages from the revision of Guix you're
4259 currently running with packages available in a different revision of Guix.
4260 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4261 revisions in arbitrary ways.
4263 @cindex inferior packages
4264 Technically, an ``inferior'' is essentially a separate Guix process connected
4265 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4266 @code{(guix inferior)} module allows you to create inferiors and to
4267 communicate with them. It also provides a high-level interface to browse and
4268 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4270 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4271 to interact with a separate revision of Guix. For example, let's assume you
4272 want to install in your profile the current @code{guile} package, along with
4273 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4274 because the newer @code{guile-json} has an incompatible API and you want to
4275 run your code against the old API@. To do that, you could write a manifest for
4276 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4277 manifest, you would create an inferior for that old Guix revision you care
4278 about, and you would look up the @code{guile-json} package in the inferior:
4281 (use-modules (guix inferior) (guix channels)
4282 (srfi srfi-1)) ;for 'first'
4285 ;; This is the old revision from which we want to
4286 ;; extract guile-json.
4289 (url "https://git.savannah.gnu.org/git/guix.git")
4291 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4294 ;; An inferior representing the above revision.
4295 (inferior-for-channels channels))
4297 ;; Now create a manifest with the current "guile" package
4298 ;; and the old "guile-json" package.
4300 (list (first (lookup-inferior-packages inferior "guile-json"))
4301 (specification->package "guile")))
4304 On its first run, @command{guix package --manifest} might have to build the
4305 channel you specified before it can create the inferior; subsequent runs will
4306 be much faster because the Guix revision will be cached.
4308 The @code{(guix inferior)} module provides the following procedures to open an
4311 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4312 [#:cache-directory] [#:ttl]
4313 Return an inferior for @var{channels}, a list of channels. Use the cache at
4314 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4315 This procedure opens a new connection to the build daemon.
4317 As a side effect, this procedure may build or substitute binaries for
4318 @var{channels}, which can take time.
4321 @deffn {Scheme Procedure} open-inferior @var{directory} @
4322 [#:command "bin/guix"]
4323 Open the inferior Guix in @var{directory}, running
4324 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4325 the inferior could not be launched.
4328 @cindex inferior packages
4329 The procedures listed below allow you to obtain and manipulate inferior
4332 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4333 Return the list of packages known to @var{inferior}.
4336 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4338 Return the sorted list of inferior packages matching @var{name} in
4339 @var{inferior}, with highest version numbers first. If @var{version} is true,
4340 return only packages with a version number prefixed by @var{version}.
4343 @deffn {Scheme Procedure} inferior-package? @var{obj}
4344 Return true if @var{obj} is an inferior package.
4347 @deffn {Scheme Procedure} inferior-package-name @var{package}
4348 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4349 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4350 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4351 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4352 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4353 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4354 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4355 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4356 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4357 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4358 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4359 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4360 These procedures are the counterpart of package record accessors
4361 (@pxref{package Reference}). Most of them work by querying the inferior
4362 @var{package} comes from, so the inferior must still be live when you call
4366 Inferior packages can be used transparently like any other package or
4367 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4368 transparently handled by the @code{packages->manifest} procedure, which is
4369 commonly use in manifests (@pxref{Invoking guix package, the
4370 @option{--manifest} option of @command{guix package}}). Thus you can insert
4371 an inferior package pretty much anywhere you would insert a regular package:
4372 in manifests, in the @code{packages} field of your @code{operating-system}
4373 declaration, and so on.
4375 @node Invoking guix describe
4376 @section Invoking @command{guix describe}
4378 @cindex reproducibility
4379 @cindex replicating Guix
4380 Often you may want to answer questions like: ``Which revision of Guix am I
4381 using?'' or ``Which channels am I using?'' This is useful information in many
4382 situations: if you want to @emph{replicate} an environment on a different
4383 machine or user account, if you want to report a bug or to determine what
4384 change in the channels you are using caused it, or if you want to record your
4385 system state for reproducibility purposes. The @command{guix describe}
4386 command answers these questions.
4388 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4389 displays the channel(s) that it was built from, including their repository URL
4390 and commit IDs (@pxref{Channels}):
4394 Generation 10 Sep 03 2018 17:32:44 (current)
4396 repository URL: https://git.savannah.gnu.org/git/guix.git
4398 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4401 If you're familiar with the Git version control system, this is similar in
4402 spirit to @command{git describe}; the output is also similar to that of
4403 @command{guix pull --list-generations}, but limited to the current generation
4404 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4405 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4406 information is all it takes to describe the revision of Guix you're using, and
4407 also to replicate it.
4409 To make it easier to replicate Guix, @command{guix describe} can also be asked
4410 to return a list of channels instead of the human-readable description above:
4413 $ guix describe -f channels
4416 (url "https://git.savannah.gnu.org/git/guix.git")
4418 "e0fa68c7718fffd33d81af415279d6ddb518f727")))
4422 You can save this to a file and feed it to @command{guix pull -C} on some
4423 other machine or at a later point in time, which will instantiate @emph{this
4424 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4425 From there on, since you're able to deploy the same revision of Guix, you can
4426 just as well @emph{replicate a complete software environment}. We humbly
4427 think that this is @emph{awesome}, and we hope you'll like it too!
4429 The details of the options supported by @command{guix describe} are as
4433 @item --format=@var{format}
4434 @itemx -f @var{format}
4435 Produce output in the specified @var{format}, one of:
4439 produce human-readable output;
4441 produce a list of channel specifications that can be passed to @command{guix
4442 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4446 produce a list of channel specifications in JSON format;
4448 produce a list of channel specifications in Recutils format.
4451 @item --profile=@var{profile}
4452 @itemx -p @var{profile}
4453 Display information about @var{profile}.
4456 @node Invoking guix archive
4457 @section Invoking @command{guix archive}
4459 @cindex @command{guix archive}
4461 The @command{guix archive} command allows users to @dfn{export} files
4462 from the store into a single archive, and to later @dfn{import} them on
4463 a machine that runs Guix.
4464 In particular, it allows store files to be transferred from one machine
4465 to the store on another machine.
4468 If you're looking for a way to produce archives in a format suitable for
4469 tools other than Guix, @pxref{Invoking guix pack}.
4472 @cindex exporting store items
4473 To export store files as an archive to standard output, run:
4476 guix archive --export @var{options} @var{specifications}...
4479 @var{specifications} may be either store file names or package
4480 specifications, as for @command{guix package} (@pxref{Invoking guix
4481 package}). For instance, the following command creates an archive
4482 containing the @code{gui} output of the @code{git} package and the main
4483 output of @code{emacs}:
4486 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4489 If the specified packages are not built yet, @command{guix archive}
4490 automatically builds them. The build process may be controlled with the
4491 common build options (@pxref{Common Build Options}).
4493 To transfer the @code{emacs} package to a machine connected over SSH,
4497 guix archive --export -r emacs | ssh the-machine guix archive --import
4501 Similarly, a complete user profile may be transferred from one machine
4502 to another like this:
4505 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4506 ssh the-machine guix archive --import
4510 However, note that, in both examples, all of @code{emacs} and the
4511 profile as well as all of their dependencies are transferred (due to
4512 @code{-r}), regardless of what is already available in the store on the
4513 target machine. The @code{--missing} option can help figure out which
4514 items are missing from the target store. The @command{guix copy}
4515 command simplifies and optimizes this whole process, so this is probably
4516 what you should use in this case (@pxref{Invoking guix copy}).
4518 @cindex nar, archive format
4519 @cindex normalized archive (nar)
4520 Archives are stored in the ``normalized archive'' or ``nar'' format, which is
4521 comparable in spirit to `tar', but with differences
4522 that make it more appropriate for our purposes. First, rather than
4523 recording all Unix metadata for each file, the nar format only mentions
4524 the file type (regular, directory, or symbolic link); Unix permissions
4525 and owner/group are dismissed. Second, the order in which directory
4526 entries are stored always follows the order of file names according to
4527 the C locale collation order. This makes archive production fully
4530 When exporting, the daemon digitally signs the contents of the archive,
4531 and that digital signature is appended. When importing, the daemon
4532 verifies the signature and rejects the import in case of an invalid
4533 signature or if the signing key is not authorized.
4534 @c FIXME: Add xref to daemon doc about signatures.
4536 The main options are:
4540 Export the specified store files or packages (see below.) Write the
4541 resulting archive to the standard output.
4543 Dependencies are @emph{not} included in the output, unless
4544 @code{--recursive} is passed.
4548 When combined with @code{--export}, this instructs @command{guix
4549 archive} to include dependencies of the given items in the archive.
4550 Thus, the resulting archive is self-contained: it contains the closure
4551 of the exported store items.
4554 Read an archive from the standard input, and import the files listed
4555 therein into the store. Abort if the archive has an invalid digital
4556 signature, or if it is signed by a public key not among the authorized
4557 keys (see @code{--authorize} below.)
4560 Read a list of store file names from the standard input, one per line,
4561 and write on the standard output the subset of these files missing from
4564 @item --generate-key[=@var{parameters}]
4565 @cindex signing, archives
4566 Generate a new key pair for the daemon. This is a prerequisite before
4567 archives can be exported with @code{--export}. Note that this operation
4568 usually takes time, because it needs to gather enough entropy to
4569 generate the key pair.
4571 The generated key pair is typically stored under @file{/etc/guix}, in
4572 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4573 key, which must be kept secret.) When @var{parameters} is omitted,
4574 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4575 versions before 1.6.0, it is a 4096-bit RSA key.
4576 Alternatively, @var{parameters} can specify
4577 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4578 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4579 Libgcrypt Reference Manual}).
4582 @cindex authorizing, archives
4583 Authorize imports signed by the public key passed on standard input.
4584 The public key must be in ``s-expression advanced format''---i.e., the
4585 same format as the @file{signing-key.pub} file.
4587 The list of authorized keys is kept in the human-editable file
4588 @file{/etc/guix/acl}. The file contains
4589 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4590 s-expressions''} and is structured as an access-control list in the
4591 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4594 @item --extract=@var{directory}
4595 @itemx -x @var{directory}
4596 Read a single-item archive as served by substitute servers
4597 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4598 low-level operation needed in only very narrow use cases; see below.
4600 For example, the following command extracts the substitute for Emacs
4601 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4605 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-emacs-24.5 \
4606 | bunzip2 | guix archive -x /tmp/emacs
4609 Single-item archives are different from multiple-item archives produced
4610 by @command{guix archive --export}; they contain a single store item,
4611 and they do @emph{not} embed a signature. Thus this operation does
4612 @emph{no} signature verification and its output should be considered
4615 The primary purpose of this operation is to facilitate inspection of
4616 archive contents coming from possibly untrusted substitute servers.
4620 Read a single-item archive as served by substitute servers
4621 (@pxref{Substitutes}) and print the list of files it contains, as in
4626 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4627 | lzip -d | guix archive -t
4633 @c *********************************************************************
4635 @chapter Development
4637 @cindex software development
4638 If you are a software developer, Guix provides tools that you should find
4639 helpful---independently of the language you're developing in. This is what
4640 this chapter is about.
4642 The @command{guix environment} command provides a convenient way to set up
4643 @dfn{development environments} containing all the dependencies and tools
4644 necessary to work on the software package of your choice. The @command{guix
4645 pack} command allows you to create @dfn{application bundles} that can be
4646 easily distributed to users who do not run Guix.
4649 * Invoking guix environment:: Setting up development environments.
4650 * Invoking guix pack:: Creating software bundles.
4653 @node Invoking guix environment
4654 @section Invoking @command{guix environment}
4656 @cindex reproducible build environments
4657 @cindex development environments
4658 @cindex @command{guix environment}
4659 @cindex environment, package build environment
4660 The purpose of @command{guix environment} is to assist hackers in
4661 creating reproducible development environments without polluting their
4662 package profile. The @command{guix environment} tool takes one or more
4663 packages, builds all of their inputs, and creates a shell
4664 environment to use them.
4666 The general syntax is:
4669 guix environment @var{options} @var{package}@dots{}
4672 The following example spawns a new shell set up for the development of
4676 guix environment guile
4679 If the needed dependencies are not built yet, @command{guix environment}
4680 automatically builds them. The environment of the new shell is an augmented
4681 version of the environment that @command{guix environment} was run in.
4682 It contains the necessary search paths for building the given package
4683 added to the existing environment variables. To create a ``pure''
4684 environment, in which the original environment variables have been unset,
4685 use the @code{--pure} option@footnote{Users sometimes wrongfully augment
4686 environment variables such as @code{PATH} in their @file{~/.bashrc}
4687 file. As a consequence, when @code{guix environment} launches it, Bash
4688 may read @file{~/.bashrc}, thereby introducing ``impurities'' in these
4689 environment variables. It is an error to define such environment
4690 variables in @file{.bashrc}; instead, they should be defined in
4691 @file{.bash_profile}, which is sourced only by log-in shells.
4692 @xref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}, for
4693 details on Bash start-up files.}.
4695 @vindex GUIX_ENVIRONMENT
4696 @command{guix environment} defines the @code{GUIX_ENVIRONMENT}
4697 variable in the shell it spawns; its value is the file name of the
4698 profile of this environment. This allows users to, say, define a
4699 specific prompt for development environments in their @file{.bashrc}
4700 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
4703 if [ -n "$GUIX_ENVIRONMENT" ]
4705 export PS1="\u@@\h \w [dev]\$ "
4710 ...@: or to browse the profile:
4713 $ ls "$GUIX_ENVIRONMENT/bin"
4716 Additionally, more than one package may be specified, in which case the
4717 union of the inputs for the given packages are used. For example, the
4718 command below spawns a shell where all of the dependencies of both Guile
4719 and Emacs are available:
4722 guix environment guile emacs
4725 Sometimes an interactive shell session is not desired. An arbitrary
4726 command may be invoked by placing the @code{--} token to separate the
4727 command from the rest of the arguments:
4730 guix environment guile -- make -j4
4733 In other situations, it is more convenient to specify the list of
4734 packages needed in the environment. For example, the following command
4735 runs @command{python} from an environment containing Python@tie{}2.7 and
4739 guix environment --ad-hoc python2-numpy python-2.7 -- python
4742 Furthermore, one might want the dependencies of a package and also some
4743 additional packages that are not build-time or runtime dependencies, but
4744 are useful when developing nonetheless. Because of this, the
4745 @code{--ad-hoc} flag is positional. Packages appearing before
4746 @code{--ad-hoc} are interpreted as packages whose dependencies will be
4747 added to the environment. Packages appearing after are interpreted as
4748 packages that will be added to the environment directly. For example,
4749 the following command creates a Guix development environment that
4750 additionally includes Git and strace:
4753 guix environment guix --ad-hoc git strace
4756 Sometimes it is desirable to isolate the environment as much as
4757 possible, for maximal purity and reproducibility. In particular, when
4758 using Guix on a host distro that is not Guix System, it is desirable to
4759 prevent access to @file{/usr/bin} and other system-wide resources from
4760 the development environment. For example, the following command spawns
4761 a Guile REPL in a ``container'' where only the store and the current
4762 working directory are mounted:
4765 guix environment --ad-hoc --container guile -- guile
4769 The @code{--container} option requires Linux-libre 3.19 or newer.
4772 The available options are summarized below.
4775 @item --root=@var{file}
4776 @itemx -r @var{file}
4777 @cindex persistent environment
4778 @cindex garbage collector root, for environments
4779 Make @var{file} a symlink to the profile for this environment, and
4780 register it as a garbage collector root.
4782 This is useful if you want to protect your environment from garbage
4783 collection, to make it ``persistent''.
4785 When this option is omitted, the environment is protected from garbage
4786 collection only for the duration of the @command{guix environment}
4787 session. This means that next time you recreate the same environment,
4788 you could have to rebuild or re-download packages. @xref{Invoking guix
4789 gc}, for more on GC roots.
4791 @item --expression=@var{expr}
4792 @itemx -e @var{expr}
4793 Create an environment for the package or list of packages that
4794 @var{expr} evaluates to.
4796 For example, running:
4799 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
4802 starts a shell with the environment for this specific variant of the
4808 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
4811 starts a shell with all the base system packages available.
4813 The above commands only use the default output of the given packages.
4814 To select other outputs, two element tuples can be specified:
4817 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
4820 @item --load=@var{file}
4821 @itemx -l @var{file}
4822 Create an environment for the package or list of packages that the code
4823 within @var{file} evaluates to.
4825 As an example, @var{file} might contain a definition like this
4826 (@pxref{Defining Packages}):
4829 @verbatiminclude environment-gdb.scm
4832 @item --manifest=@var{file}
4833 @itemx -m @var{file}
4834 Create an environment for the packages contained in the manifest object
4835 returned by the Scheme code in @var{file}. This option can be repeated
4836 several times, in which case the manifests are concatenated.
4838 This is similar to the same-named option in @command{guix package}
4839 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
4843 Include all specified packages in the resulting environment, as if an
4844 @i{ad hoc} package were defined with them as inputs. This option is
4845 useful for quickly creating an environment without having to write a
4846 package expression to contain the desired inputs.
4848 For instance, the command:
4851 guix environment --ad-hoc guile guile-sdl -- guile
4854 runs @command{guile} in an environment where Guile and Guile-SDL are
4857 Note that this example implicitly asks for the default output of
4858 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
4859 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
4860 of @code{glib} (@pxref{Packages with Multiple Outputs}).
4862 This option may be composed with the default behavior of @command{guix
4863 environment}. Packages appearing before @code{--ad-hoc} are interpreted
4864 as packages whose dependencies will be added to the environment, the
4865 default behavior. Packages appearing after are interpreted as packages
4866 that will be added to the environment directly.
4869 Unset existing environment variables when building the new environment, except
4870 those specified with @option{--preserve} (see below.) This has the effect of
4871 creating an environment in which search paths only contain package inputs.
4873 @item --preserve=@var{regexp}
4874 @itemx -E @var{regexp}
4875 When used alongside @option{--pure}, preserve the environment variables
4876 matching @var{regexp}---in other words, put them on a ``white list'' of
4877 environment variables that must be preserved. This option can be repeated
4881 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
4885 This example runs @command{mpirun} in a context where the only environment
4886 variables defined are @code{PATH}, environment variables whose name starts
4887 with @code{SLURM}, as well as the usual ``precious'' variables (@code{HOME},
4890 @item --search-paths
4891 Display the environment variable definitions that make up the
4894 @item --system=@var{system}
4895 @itemx -s @var{system}
4896 Attempt to build for @var{system}---e.g., @code{i686-linux}.
4901 Run @var{command} within an isolated container. The current working
4902 directory outside the container is mapped inside the container.
4903 Additionally, unless overridden with @code{--user}, a dummy home
4904 directory is created that matches the current user's home directory, and
4905 @file{/etc/passwd} is configured accordingly.
4907 The spawned process runs as the current user outside the container. Inside
4908 the container, it has the same UID and GID as the current user, unless
4909 @option{--user} is passed (see below.)
4913 For containers, share the network namespace with the host system.
4914 Containers created without this flag only have access to the loopback
4917 @item --link-profile
4919 For containers, link the environment profile to
4920 @file{~/.guix-profile} within the container. This is equivalent to
4921 running the command @command{ln -s $GUIX_ENVIRONMENT ~/.guix-profile}
4922 within the container. Linking will fail and abort the environment if
4923 the directory already exists, which will certainly be the case if
4924 @command{guix environment} was invoked in the user's home directory.
4926 Certain packages are configured to look in
4927 @code{~/.guix-profile} for configuration files and data;@footnote{For
4928 example, the @code{fontconfig} package inspects
4929 @file{~/.guix-profile/share/fonts} for additional fonts.}
4930 @code{--link-profile} allows these programs to behave as expected within
4933 @item --user=@var{user}
4934 @itemx -u @var{user}
4935 For containers, use the username @var{user} in place of the current
4936 user. The generated @file{/etc/passwd} entry within the container will
4937 contain the name @var{user}, the home directory will be
4938 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
4939 the UID and GID inside the container are 1000. @var{user}
4940 need not exist on the system.
4942 Additionally, any shared or exposed path (see @code{--share} and
4943 @code{--expose} respectively) whose target is within the current user's
4944 home directory will be remapped relative to @file{/home/USER}; this
4945 includes the automatic mapping of the current working directory.
4948 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
4950 guix environment --container --user=foo \
4951 --expose=$HOME/test \
4952 --expose=/tmp/target=$HOME/target
4955 While this will limit the leaking of user identity through home paths
4956 and each of the user fields, this is only one useful component of a
4957 broader privacy/anonymity solution---not one in and of itself.
4960 For containers, the default behavior is to share the current working
4961 directory with the isolated container and immediately change to that
4962 directory within the container. If this is undesirable, @code{--no-cwd}
4963 will cause the current working directory to @emph{not} be automatically
4964 shared and will change to the user's home directory within the container
4965 instead. See also @code{--user}.
4967 @item --expose=@var{source}[=@var{target}]
4968 @itemx --share=@var{source}[=@var{target}]
4969 For containers, @code{--expose} (resp. @code{--share}) exposes the file
4970 system @var{source} from the host system as the read-only
4971 (resp. writable) file system @var{target} within the container. If
4972 @var{target} is not specified, @var{source} is used as the target mount
4973 point in the container.
4975 The example below spawns a Guile REPL in a container in which the user's
4976 home directory is accessible read-only via the @file{/exchange}
4980 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
4985 @command{guix environment}
4986 also supports all of the common build options that @command{guix
4987 build} supports (@pxref{Common Build Options}) as well as package
4988 transformation options (@pxref{Package Transformation Options}).
4990 @node Invoking guix pack
4991 @section Invoking @command{guix pack}
4993 Occasionally you want to pass software to people who are not (yet!)
4994 lucky enough to be using Guix. You'd tell them to run @command{guix
4995 package -i @var{something}}, but that's not possible in this case. This
4996 is where @command{guix pack} comes in.
4999 If you are looking for ways to exchange binaries among machines that
5000 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5001 publish}, and @ref{Invoking guix archive}.
5006 @cindex application bundle
5007 @cindex software bundle
5008 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5009 @dfn{software bundle}: it creates a tarball or some other archive
5010 containing the binaries of the software you're interested in, and all
5011 its dependencies. The resulting archive can be used on any machine that
5012 does not have Guix, and people can run the exact same binaries as those
5013 you have with Guix. The pack itself is created in a bit-reproducible
5014 fashion, so anyone can verify that it really contains the build results
5015 that you pretend to be shipping.
5017 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5018 their dependencies, you can run:
5021 $ guix pack guile emacs geiser
5023 /gnu/store/@dots{}-pack.tar.gz
5026 The result here is a tarball containing a @file{/gnu/store} directory
5027 with all the relevant packages. The resulting tarball contains a
5028 @dfn{profile} with the three packages of interest; the profile is the
5029 same as would be created by @command{guix package -i}. It is this
5030 mechanism that is used to create Guix's own standalone binary tarball
5031 (@pxref{Binary Installation}).
5033 Users of this pack would have to run
5034 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5035 find inconvenient. To work around it, you can create, say, a
5036 @file{/opt/gnu/bin} symlink to the profile:
5039 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5043 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5045 @cindex relocatable binaries, with @command{guix pack}
5046 What if the recipient of your pack does not have root privileges on
5047 their machine, and thus cannot unpack it in the root file system? In
5048 that case, you will want to use the @code{--relocatable} option (see
5049 below). This option produces @dfn{relocatable binaries}, meaning they
5050 they can be placed anywhere in the file system hierarchy: in the example
5051 above, users can unpack your tarball in their home directory and
5052 directly run @file{./opt/gnu/bin/guile}.
5054 @cindex Docker, build an image with guix pack
5055 Alternatively, you can produce a pack in the Docker image format using
5056 the following command:
5059 guix pack -f docker -S /bin=bin guile guile-readline
5063 The result is a tarball that can be passed to the @command{docker load}
5064 command, followed by @code{docker run}:
5067 docker load < @var{file}
5068 docker run -ti guile-guile-readline /bin/guile
5072 where @var{file} is the image returned by @var{guix pack}, and
5073 @code{guile-guile-readline} is its ``image tag''. See the
5074 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5075 documentation} for more information.
5077 @cindex Singularity, build an image with guix pack
5078 @cindex SquashFS, build an image with guix pack
5079 Yet another option is to produce a SquashFS image with the following
5083 guix pack -f squashfs bash guile emacs geiser
5087 The result is a SquashFS file system image that can either be mounted or
5088 directly be used as a file system container image with the
5089 @uref{https://singularity.lbl.gov, Singularity container execution
5090 environment}, using commands like @command{singularity shell} or
5091 @command{singularity exec}.
5093 Several command-line options allow you to customize your pack:
5096 @item --format=@var{format}
5097 @itemx -f @var{format}
5098 Produce a pack in the given @var{format}.
5100 The available formats are:
5104 This is the default format. It produces a tarball containing all the
5105 specified binaries and symlinks.
5108 This produces a tarball that follows the
5109 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5110 Docker Image Specification}. The ``repository name'' as it appears in
5111 the output of the @command{docker images} command is computed from
5112 package names passed on the command line or in the manifest file.
5115 This produces a SquashFS image containing all the specified binaries and
5116 symlinks, as well as empty mount points for virtual file systems like
5120 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5121 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5122 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5123 with something like:
5126 guix pack -f squashfs bash @dots{}
5129 If you forget the @code{bash} (or similar) package, @command{singularity
5130 run} and @command{singularity exec} will fail with an unhelpful ``no
5131 such file or directory'' message.
5135 @cindex relocatable binaries
5138 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5139 anywhere in the file system hierarchy and run from there.
5141 When this option is passed once, the resulting binaries require support for
5142 @dfn{user namespaces} in the kernel Linux; when passed
5143 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5144 PRoot support, can be thought of as the abbreviation of ``Really
5145 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to PRoot
5146 if user namespaces are unavailable, and essentially work anywhere---see below
5147 for the implications.
5149 For example, if you create a pack containing Bash with:
5152 guix pack -RR -S /mybin=bin bash
5156 ...@: you can copy that pack to a machine that lacks Guix, and from your
5157 home directory as a normal user, run:
5165 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5166 @file{/gnu/store} shows up and contains all the dependencies of
5167 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5168 altogether! That is probably the simplest way to deploy Guix-built
5169 software on a non-Guix machine.
5172 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5173 the kernel Linux, which allows unprivileged users to mount or change root.
5174 Old versions of Linux did not support it, and some GNU/Linux distributions
5177 To produce relocatable binaries that work even in the absence of user
5178 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5179 case, binaries will try user namespace support and fall back to PRoot if user
5180 namespaces are not supported.
5182 The @uref{https://proot-me.github.io/, PRoot} program provides the necessary
5183 support for file system virtualization. It achieves that by using the
5184 @code{ptrace} system call on the running program. This approach has the
5185 advantage to work without requiring special kernel support, but it incurs
5186 run-time overhead every time a system call is made.
5189 @cindex entry point, for Docker images
5190 @item --entry-point=@var{command}
5191 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5192 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5193 support it. @var{command} must be relative to the profile contained in the
5196 The entry point specifies the command that tools like @code{docker run} or
5197 @code{singularity run} automatically start by default. For example, you can
5201 guix pack -f docker --entry-point=bin/guile guile
5204 The resulting pack can easily be loaded and @code{docker run} with no extra
5205 arguments will spawn @code{bin/guile}:
5208 docker load -i pack.tar.gz
5209 docker run @var{image-id}
5212 @item --expression=@var{expr}
5213 @itemx -e @var{expr}
5214 Consider the package @var{expr} evaluates to.
5216 This has the same purpose as the same-named option in @command{guix
5217 build} (@pxref{Additional Build Options, @code{--expression} in
5218 @command{guix build}}).
5220 @item --manifest=@var{file}
5221 @itemx -m @var{file}
5222 Use the packages contained in the manifest object returned by the Scheme
5223 code in @var{file}. This option can be repeated several times, in which
5224 case the manifests are concatenated.
5226 This has a similar purpose as the same-named option in @command{guix
5227 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
5228 same manifest files. It allows you to define a collection of packages
5229 once and use it both for creating profiles and for creating archives
5230 for use on machines that do not have Guix installed. Note that you can
5231 specify @emph{either} a manifest file @emph{or} a list of packages,
5234 @item --system=@var{system}
5235 @itemx -s @var{system}
5236 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
5237 the system type of the build host.
5239 @item --target=@var{triplet}
5240 @cindex cross-compilation
5241 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
5242 as @code{"mips64el-linux-gnu"} (@pxref{Specifying target triplets, GNU
5243 configuration triplets,, autoconf, Autoconf}).
5245 @item --compression=@var{tool}
5246 @itemx -C @var{tool}
5247 Compress the resulting tarball using @var{tool}---one of @code{gzip},
5248 @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no compression.
5250 @item --symlink=@var{spec}
5251 @itemx -S @var{spec}
5252 Add the symlinks specified by @var{spec} to the pack. This option can
5253 appear several times.
5255 @var{spec} has the form @code{@var{source}=@var{target}}, where
5256 @var{source} is the symlink that will be created and @var{target} is the
5259 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
5260 symlink pointing to the @file{bin} sub-directory of the profile.
5262 @item --save-provenance
5263 Save provenance information for the packages passed on the command line.
5264 Provenance information includes the URL and commit of the channels in use
5267 Provenance information is saved in the
5268 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
5269 usual package metadata---the name and version of each package, their
5270 propagated inputs, and so on. It is useful information to the recipient of
5271 the pack, who then knows how the pack was (supposedly) obtained.
5273 This option is not enabled by default because, like timestamps, provenance
5274 information contributes nothing to the build process. In other words, there
5275 is an infinity of channel URLs and commit IDs that can lead to the same pack.
5276 Recording such ``silent'' metadata in the output thus potentially breaks the
5277 source-to-binary bitwise reproducibility property.
5279 @item --root=@var{file}
5280 @itemx -r @var{file}
5281 @cindex garbage collector root, for packs
5282 Make @var{file} a symlink to the resulting pack, and register it as a garbage
5285 @item --localstatedir
5286 @itemx --profile-name=@var{name}
5287 Include the ``local state directory'', @file{/var/guix}, in the resulting
5288 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
5289 profile---by default @var{name} is @code{guix-profile}, which corresponds to
5290 @file{~root/.guix-profile}.
5292 @file{/var/guix} contains the store database (@pxref{The Store}) as well
5293 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
5294 the pack means that the store is ``complete'' and manageable by Guix;
5295 not providing it pack means that the store is ``dead'': items cannot be
5296 added to it or removed from it after extraction of the pack.
5298 One use case for this is the Guix self-contained binary tarball
5299 (@pxref{Binary Installation}).
5303 Print the name of the derivation that builds the pack.
5306 Use the bootstrap binaries to build the pack. This option is only
5307 useful to Guix developers.
5310 In addition, @command{guix pack} supports all the common build options
5311 (@pxref{Common Build Options}) and all the package transformation
5312 options (@pxref{Package Transformation Options}).
5315 @c *********************************************************************
5316 @node Programming Interface
5317 @chapter Programming Interface
5319 GNU Guix provides several Scheme programming interfaces (APIs) to
5320 define, build, and query packages. The first interface allows users to
5321 write high-level package definitions. These definitions refer to
5322 familiar packaging concepts, such as the name and version of a package,
5323 its build system, and its dependencies. These definitions can then be
5324 turned into concrete build actions.
5326 Build actions are performed by the Guix daemon, on behalf of users. In a
5327 standard setup, the daemon has write access to the store---the
5328 @file{/gnu/store} directory---whereas users do not. The recommended
5329 setup also has the daemon perform builds in chroots, under a specific
5330 build users, to minimize interference with the rest of the system.
5333 Lower-level APIs are available to interact with the daemon and the
5334 store. To instruct the daemon to perform a build action, users actually
5335 provide it with a @dfn{derivation}. A derivation is a low-level
5336 representation of the build actions to be taken, and the environment in
5337 which they should occur---derivations are to package definitions what
5338 assembly is to C programs. The term ``derivation'' comes from the fact
5339 that build results @emph{derive} from them.
5341 This chapter describes all these APIs in turn, starting from high-level
5342 package definitions.
5345 * Package Modules:: Packages from the programmer's viewpoint.
5346 * Defining Packages:: Defining new packages.
5347 * Build Systems:: Specifying how packages are built.
5348 * The Store:: Manipulating the package store.
5349 * Derivations:: Low-level interface to package derivations.
5350 * The Store Monad:: Purely functional interface to the store.
5351 * G-Expressions:: Manipulating build expressions.
5352 * Invoking guix repl:: Fiddling with Guix interactively.
5355 @node Package Modules
5356 @section Package Modules
5358 From a programming viewpoint, the package definitions of the
5359 GNU distribution are provided by Guile modules in the @code{(gnu packages
5360 @dots{})} name space@footnote{Note that packages under the @code{(gnu
5361 packages @dots{})} module name space are not necessarily ``GNU
5362 packages''. This module naming scheme follows the usual Guile module
5363 naming convention: @code{gnu} means that these modules are distributed
5364 as part of the GNU system, and @code{packages} identifies modules that
5365 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
5366 Reference Manual}). For instance, the @code{(gnu packages emacs)}
5367 module exports a variable named @code{emacs}, which is bound to a
5368 @code{<package>} object (@pxref{Defining Packages}).
5370 The @code{(gnu packages @dots{})} module name space is
5371 automatically scanned for packages by the command-line tools. For
5372 instance, when running @code{guix install emacs}, all the @code{(gnu
5373 packages @dots{})} modules are scanned until one that exports a package
5374 object whose name is @code{emacs} is found. This package search
5375 facility is implemented in the @code{(gnu packages)} module.
5377 @cindex customization, of packages
5378 @cindex package module search path
5379 Users can store package definitions in modules with different
5380 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
5381 name and module name must match. For instance, the @code{(my-packages
5382 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
5383 relative to the load path specified with @option{--load-path} or
5384 @code{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
5385 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
5386 these package definitions visible to the user interfaces:
5390 By adding the directory containing your package modules to the search path
5391 with the @code{-L} flag of @command{guix package} and other commands
5392 (@pxref{Common Build Options}), or by setting the @code{GUIX_PACKAGE_PATH}
5393 environment variable described below.
5396 By defining a @dfn{channel} and configuring @command{guix pull} so that it
5397 pulls from it. A channel is essentially a Git repository containing package
5398 modules. @xref{Channels}, for more information on how to define and use
5402 @code{GUIX_PACKAGE_PATH} works similarly to other search path variables:
5404 @defvr {Environment Variable} GUIX_PACKAGE_PATH
5405 This is a colon-separated list of directories to search for additional
5406 package modules. Directories listed in this variable take precedence
5407 over the own modules of the distribution.
5410 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
5411 each package is built based solely on other packages in the
5412 distribution. The root of this dependency graph is a small set of
5413 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
5414 bootstrap)} module. For more information on bootstrapping,
5415 @pxref{Bootstrapping}.
5417 @node Defining Packages
5418 @section Defining Packages
5420 The high-level interface to package definitions is implemented in the
5421 @code{(guix packages)} and @code{(guix build-system)} modules. As an
5422 example, the package definition, or @dfn{recipe}, for the GNU Hello
5423 package looks like this:
5426 (define-module (gnu packages hello)
5427 #:use-module (guix packages)
5428 #:use-module (guix download)
5429 #:use-module (guix build-system gnu)
5430 #:use-module (guix licenses)
5431 #:use-module (gnu packages gawk))
5433 (define-public hello
5439 (uri (string-append "mirror://gnu/hello/hello-" version
5443 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
5444 (build-system gnu-build-system)
5445 (arguments '(#:configure-flags '("--enable-silent-rules")))
5446 (inputs `(("gawk" ,gawk)))
5447 (synopsis "Hello, GNU world: An example GNU package")
5448 (description "Guess what GNU Hello prints!")
5449 (home-page "https://www.gnu.org/software/hello/")
5454 Without being a Scheme expert, the reader may have guessed the meaning
5455 of the various fields here. This expression binds the variable
5456 @code{hello} to a @code{<package>} object, which is essentially a record
5457 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
5458 This package object can be inspected using procedures found in the
5459 @code{(guix packages)} module; for instance, @code{(package-name hello)}
5460 returns---surprise!---@code{"hello"}.
5462 With luck, you may be able to import part or all of the definition of
5463 the package you are interested in from another repository, using the
5464 @code{guix import} command (@pxref{Invoking guix import}).
5466 In the example above, @var{hello} is defined in a module of its own,
5467 @code{(gnu packages hello)}. Technically, this is not strictly
5468 necessary, but it is convenient to do so: all the packages defined in
5469 modules under @code{(gnu packages @dots{})} are automatically known to
5470 the command-line tools (@pxref{Package Modules}).
5472 There are a few points worth noting in the above package definition:
5476 The @code{source} field of the package is an @code{<origin>} object
5477 (@pxref{origin Reference}, for the complete reference).
5478 Here, the @code{url-fetch} method from @code{(guix download)} is used,
5479 meaning that the source is a file to be downloaded over FTP or HTTP.
5481 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
5482 the GNU mirrors defined in @code{(guix download)}.
5484 The @code{sha256} field specifies the expected SHA256 hash of the file
5485 being downloaded. It is mandatory, and allows Guix to check the
5486 integrity of the file. The @code{(base32 @dots{})} form introduces the
5487 base32 representation of the hash. You can obtain this information with
5488 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
5489 hash} (@pxref{Invoking guix hash}).
5492 When needed, the @code{origin} form can also have a @code{patches} field
5493 listing patches to be applied, and a @code{snippet} field giving a
5494 Scheme expression to modify the source code.
5497 @cindex GNU Build System
5498 The @code{build-system} field specifies the procedure to build the
5499 package (@pxref{Build Systems}). Here, @var{gnu-build-system}
5500 represents the familiar GNU Build System, where packages may be
5501 configured, built, and installed with the usual @code{./configure &&
5502 make && make check && make install} command sequence.
5505 The @code{arguments} field specifies options for the build system
5506 (@pxref{Build Systems}). Here it is interpreted by
5507 @var{gnu-build-system} as a request run @file{configure} with the
5508 @code{--enable-silent-rules} flag.
5514 What about these quote (@code{'}) characters? They are Scheme syntax to
5515 introduce a literal list; @code{'} is synonymous with @code{quote}.
5516 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
5517 for details. Here the value of the @code{arguments} field is a list of
5518 arguments passed to the build system down the road, as with @code{apply}
5519 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
5522 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
5523 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
5524 @code{#:configure-flags} is a keyword used to pass a keyword argument
5525 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
5529 The @code{inputs} field specifies inputs to the build process---i.e.,
5530 build-time or run-time dependencies of the package. Here, we define an
5531 input called @code{"gawk"} whose value is that of the @var{gawk}
5532 variable; @var{gawk} is itself bound to a @code{<package>} object.
5534 @cindex backquote (quasiquote)
5537 @cindex comma (unquote)
5541 @findex unquote-splicing
5542 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
5543 us to introduce a literal list in the @code{inputs} field, while
5544 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
5545 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
5548 Note that GCC, Coreutils, Bash, and other essential tools do not need to
5549 be specified as inputs here. Instead, @var{gnu-build-system} takes care
5550 of ensuring that they are present (@pxref{Build Systems}).
5552 However, any other dependencies need to be specified in the
5553 @code{inputs} field. Any dependency not specified here will simply be
5554 unavailable to the build process, possibly leading to a build failure.
5557 @xref{package Reference}, for a full description of possible fields.
5559 Once a package definition is in place, the
5560 package may actually be built using the @code{guix build} command-line
5561 tool (@pxref{Invoking guix build}), troubleshooting any build failures
5562 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
5563 package definition using the @command{guix edit} command
5564 (@pxref{Invoking guix edit}).
5565 @xref{Packaging Guidelines}, for
5566 more information on how to test package definitions, and
5567 @ref{Invoking guix lint}, for information on how to check a definition
5568 for style conformance.
5569 @vindex GUIX_PACKAGE_PATH
5570 Lastly, @pxref{Channels}, for information
5571 on how to extend the distribution by adding your own package definitions
5574 Finally, updating the package definition to a new upstream version
5575 can be partly automated by the @command{guix refresh} command
5576 (@pxref{Invoking guix refresh}).
5578 Behind the scenes, a derivation corresponding to the @code{<package>}
5579 object is first computed by the @code{package-derivation} procedure.
5580 That derivation is stored in a @code{.drv} file under @file{/gnu/store}.
5581 The build actions it prescribes may then be realized by using the
5582 @code{build-derivations} procedure (@pxref{The Store}).
5584 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
5585 Return the @code{<derivation>} object of @var{package} for @var{system}
5586 (@pxref{Derivations}).
5588 @var{package} must be a valid @code{<package>} object, and @var{system}
5589 must be a string denoting the target system type---e.g.,
5590 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
5591 must be a connection to the daemon, which operates on the store
5592 (@pxref{The Store}).
5596 @cindex cross-compilation
5597 Similarly, it is possible to compute a derivation that cross-builds a
5598 package for some other system:
5600 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
5601 @var{package} @var{target} [@var{system}]
5602 Return the @code{<derivation>} object of @var{package} cross-built from
5603 @var{system} to @var{target}.
5605 @var{target} must be a valid GNU triplet denoting the target hardware
5606 and operating system, such as @code{"mips64el-linux-gnu"}
5607 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
5610 @cindex package transformations
5611 @cindex input rewriting
5612 @cindex dependency tree rewriting
5613 Packages can be manipulated in arbitrary ways. An example of a useful
5614 transformation is @dfn{input rewriting}, whereby the dependency tree of
5615 a package is rewritten by replacing specific inputs by others:
5617 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
5618 [@var{rewrite-name}]
5619 Return a procedure that, when passed a package, replaces its direct and
5620 indirect dependencies (but not its implicit inputs) according to
5621 @var{replacements}. @var{replacements} is a list of package pairs; the
5622 first element of each pair is the package to replace, and the second one
5625 Optionally, @var{rewrite-name} is a one-argument procedure that takes
5626 the name of a package and returns its new name after rewrite.
5630 Consider this example:
5633 (define libressl-instead-of-openssl
5634 ;; This is a procedure to replace OPENSSL by LIBRESSL,
5636 (package-input-rewriting `((,openssl . ,libressl))))
5638 (define git-with-libressl
5639 (libressl-instead-of-openssl git))
5643 Here we first define a rewriting procedure that replaces @var{openssl}
5644 with @var{libressl}. Then we use it to define a @dfn{variant} of the
5645 @var{git} package that uses @var{libressl} instead of @var{openssl}.
5646 This is exactly what the @option{--with-input} command-line option does
5647 (@pxref{Package Transformation Options, @option{--with-input}}).
5649 The following variant of @code{package-input-rewriting} can match packages to
5650 be replaced by name rather than by identity.
5652 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements}
5653 Return a procedure that, given a package, applies the given @var{replacements} to
5654 all the package graph (excluding implicit inputs). @var{replacements} is a list of
5655 spec/procedures pair; each spec is a package specification such as @code{"gcc"} or
5656 @code{"guile@@2"}, and each procedure takes a matching package and returns a
5657 replacement for that package.
5660 The example above could be rewritten this way:
5663 (define libressl-instead-of-openssl
5664 ;; Replace all the packages called "openssl" with LibreSSL.
5665 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
5668 The key difference here is that, this time, packages are matched by spec and
5669 not by identity. In other words, any package in the graph that is called
5670 @code{openssl} will be replaced.
5672 A more generic procedure to rewrite a package dependency graph is
5673 @code{package-mapping}: it supports arbitrary changes to nodes in the
5676 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}]
5677 Return a procedure that, given a package, applies @var{proc} to all the packages
5678 depended on and returns the resulting package. The procedure stops recursion
5679 when @var{cut?} returns true for a given package.
5683 * package Reference:: The package data type.
5684 * origin Reference:: The origin data type.
5688 @node package Reference
5689 @subsection @code{package} Reference
5691 This section summarizes all the options available in @code{package}
5692 declarations (@pxref{Defining Packages}).
5694 @deftp {Data Type} package
5695 This is the data type representing a package recipe.
5699 The name of the package, as a string.
5701 @item @code{version}
5702 The version of the package, as a string.
5705 An object telling how the source code for the package should be
5706 acquired. Most of the time, this is an @code{origin} object, which
5707 denotes a file fetched from the Internet (@pxref{origin Reference}). It
5708 can also be any other ``file-like'' object such as a @code{local-file},
5709 which denotes a file from the local file system (@pxref{G-Expressions,
5710 @code{local-file}}).
5712 @item @code{build-system}
5713 The build system that should be used to build the package (@pxref{Build
5716 @item @code{arguments} (default: @code{'()})
5717 The arguments that should be passed to the build system. This is a
5718 list, typically containing sequential keyword-value pairs.
5720 @item @code{inputs} (default: @code{'()})
5721 @itemx @code{native-inputs} (default: @code{'()})
5722 @itemx @code{propagated-inputs} (default: @code{'()})
5723 @cindex inputs, of packages
5724 These fields list dependencies of the package. Each one is a list of
5725 tuples, where each tuple has a label for the input (a string) as its
5726 first element, a package, origin, or derivation as its second element,
5727 and optionally the name of the output thereof that should be used, which
5728 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
5729 more on package outputs). For example, the list below specifies three
5733 `(("libffi" ,libffi)
5734 ("libunistring" ,libunistring)
5735 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
5738 @cindex cross compilation, package dependencies
5739 The distinction between @code{native-inputs} and @code{inputs} is
5740 necessary when considering cross-compilation. When cross-compiling,
5741 dependencies listed in @code{inputs} are built for the @emph{target}
5742 architecture; conversely, dependencies listed in @code{native-inputs}
5743 are built for the architecture of the @emph{build} machine.
5745 @code{native-inputs} is typically used to list tools needed at
5746 build time, but not at run time, such as Autoconf, Automake, pkg-config,
5747 Gettext, or Bison. @command{guix lint} can report likely mistakes in
5748 this area (@pxref{Invoking guix lint}).
5750 @anchor{package-propagated-inputs}
5751 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
5752 specified packages will be automatically installed alongside the package
5753 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
5754 package}}, for information on how @command{guix package} deals with
5757 For example this is necessary when a C/C++ library needs headers of
5758 another library to compile, or when a pkg-config file refers to another
5759 one @i{via} its @code{Requires} field.
5761 Another example where @code{propagated-inputs} is useful is for languages
5762 that lack a facility to record the run-time search path akin to the
5763 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
5764 more. To ensure that libraries written in those languages can find
5765 library code they depend on at run time, run-time dependencies must be
5766 listed in @code{propagated-inputs} rather than @code{inputs}.
5768 @item @code{outputs} (default: @code{'("out")})
5769 The list of output names of the package. @xref{Packages with Multiple
5770 Outputs}, for typical uses of additional outputs.
5772 @item @code{native-search-paths} (default: @code{'()})
5773 @itemx @code{search-paths} (default: @code{'()})
5774 A list of @code{search-path-specification} objects describing
5775 search-path environment variables honored by the package.
5777 @item @code{replacement} (default: @code{#f})
5778 This must be either @code{#f} or a package object that will be used as a
5779 @dfn{replacement} for this package. @xref{Security Updates, grafts},
5782 @item @code{synopsis}
5783 A one-line description of the package.
5785 @item @code{description}
5786 A more elaborate description of the package.
5788 @item @code{license}
5789 @cindex license, of packages
5790 The license of the package; a value from @code{(guix licenses)},
5791 or a list of such values.
5793 @item @code{home-page}
5794 The URL to the home-page of the package, as a string.
5796 @item @code{supported-systems} (default: @var{%supported-systems})
5797 The list of systems supported by the package, as strings of the form
5798 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
5800 @item @code{location} (default: source location of the @code{package} form)
5801 The source location of the package. It is useful to override this when
5802 inheriting from another package, in which case this field is not
5803 automatically corrected.
5807 @deffn {Scheme Syntax} this-package
5808 When used in the @emph{lexical scope} of a package field definition, this
5809 identifier resolves to the package being defined.
5811 The example below shows how to add a package as a native input of itself when
5819 ;; When cross-compiled, Guile, for example, depends on
5820 ;; a native version of itself. Add it here.
5821 (native-inputs (if (%current-target-system)
5822 `(("self" ,this-package))
5826 It is an error to refer to @code{this-package} outside a package definition.
5829 @node origin Reference
5830 @subsection @code{origin} Reference
5832 This section summarizes all the options available in @code{origin}
5833 declarations (@pxref{Defining Packages}).
5835 @deftp {Data Type} origin
5836 This is the data type representing a source code origin.
5840 An object containing the URI of the source. The object type depends on
5841 the @code{method} (see below). For example, when using the
5842 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
5843 values are: a URL represented as a string, or a list thereof.
5846 A procedure that handles the URI.
5851 @item @var{url-fetch} from @code{(guix download)}
5852 download a file from the HTTP, HTTPS, or FTP URL specified in the
5856 @item @var{git-fetch} from @code{(guix git-download)}
5857 clone the Git version control repository, and check out the revision
5858 specified in the @code{uri} field as a @code{git-reference} object; a
5859 @code{git-reference} looks like this:
5863 (url "https://git.savannah.gnu.org/git/hello.git")
5869 A bytevector containing the SHA-256 hash of the source. Typically the
5870 @code{base32} form is used here to generate the bytevector from a
5873 You can obtain this information using @code{guix download}
5874 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
5877 @item @code{file-name} (default: @code{#f})
5878 The file name under which the source code should be saved. When this is
5879 @code{#f}, a sensible default value will be used in most cases. In case
5880 the source is fetched from a URL, the file name from the URL will be
5881 used. For version control checkouts, it is recommended to provide the
5882 file name explicitly because the default is not very descriptive.
5884 @item @code{patches} (default: @code{'()})
5885 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
5886 file-like objects}) pointing to patches to be applied to the source.
5888 This list of patches must be unconditional. In particular, it cannot
5889 depend on the value of @code{%current-system} or
5890 @code{%current-target-system}.
5892 @item @code{snippet} (default: @code{#f})
5893 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
5894 in the source directory. This is a convenient way to modify the source,
5895 sometimes more convenient than a patch.
5897 @item @code{patch-flags} (default: @code{'("-p1")})
5898 A list of command-line flags that should be passed to the @code{patch}
5901 @item @code{patch-inputs} (default: @code{#f})
5902 Input packages or derivations to the patching process. When this is
5903 @code{#f}, the usual set of inputs necessary for patching are provided,
5904 such as GNU@tie{}Patch.
5906 @item @code{modules} (default: @code{'()})
5907 A list of Guile modules that should be loaded during the patching
5908 process and while running the code in the @code{snippet} field.
5910 @item @code{patch-guile} (default: @code{#f})
5911 The Guile package that should be used in the patching process. When
5912 this is @code{#f}, a sensible default is used.
5918 @section Build Systems
5920 @cindex build system
5921 Each package definition specifies a @dfn{build system} and arguments for
5922 that build system (@pxref{Defining Packages}). This @code{build-system}
5923 field represents the build procedure of the package, as well as implicit
5924 dependencies of that build procedure.
5926 Build systems are @code{<build-system>} objects. The interface to
5927 create and manipulate them is provided by the @code{(guix build-system)}
5928 module, and actual build systems are exported by specific modules.
5930 @cindex bag (low-level package representation)
5931 Under the hood, build systems first compile package objects to
5932 @dfn{bags}. A @dfn{bag} is like a package, but with less
5933 ornamentation---in other words, a bag is a lower-level representation of
5934 a package, which includes all the inputs of that package, including some
5935 that were implicitly added by the build system. This intermediate
5936 representation is then compiled to a derivation (@pxref{Derivations}).
5938 Build systems accept an optional list of @dfn{arguments}. In package
5939 definitions, these are passed @i{via} the @code{arguments} field
5940 (@pxref{Defining Packages}). They are typically keyword arguments
5941 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
5942 Guile Reference Manual}). The value of these arguments is usually
5943 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
5944 by the daemon (@pxref{Derivations}).
5946 The main build system is @code{gnu-build-system}, which implements the
5947 standard build procedure for GNU and many other packages. It
5948 is provided by the @code{(guix build-system gnu)} module.
5950 @defvr {Scheme Variable} gnu-build-system
5951 @code{gnu-build-system} represents the GNU Build System, and variants
5952 thereof (@pxref{Configuration, configuration and makefile conventions,,
5953 standards, GNU Coding Standards}).
5955 @cindex build phases
5956 In a nutshell, packages using it are configured, built, and installed with
5957 the usual @code{./configure && make && make check && make install}
5958 command sequence. In practice, a few additional steps are often needed.
5959 All these steps are split up in separate @dfn{phases},
5960 notably@footnote{Please see the @code{(guix build gnu-build-system)}
5961 modules for more details about the build phases.}:
5965 Unpack the source tarball, and change the current directory to the
5966 extracted source tree. If the source is actually a directory, copy it
5967 to the build tree, and enter that directory.
5969 @item patch-source-shebangs
5970 Patch shebangs encountered in source files so they refer to the right
5971 store file names. For instance, this changes @code{#!/bin/sh} to
5972 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
5975 Run the @file{configure} script with a number of default options, such
5976 as @code{--prefix=/gnu/store/@dots{}}, as well as the options specified
5977 by the @code{#:configure-flags} argument.
5980 Run @code{make} with the list of flags specified with
5981 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
5982 (the default), build with @code{make -j}.
5985 Run @code{make check}, or some other target specified with
5986 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
5987 @code{#:parallel-tests?} argument is true (the default), run @code{make
5991 Run @code{make install} with the flags listed in @code{#:make-flags}.
5993 @item patch-shebangs
5994 Patch shebangs on the installed executable files.
5997 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
5998 is false), copying them to the @code{debug} output when available
5999 (@pxref{Installing Debugging Files}).
6002 @vindex %standard-phases
6003 The build-side module @code{(guix build gnu-build-system)} defines
6004 @code{%standard-phases} as the default list of build phases.
6005 @code{%standard-phases} is a list of symbol/procedure pairs, where the
6006 procedure implements the actual phase.
6008 The list of phases used for a particular package can be changed with the
6009 @code{#:phases} parameter. For instance, passing:
6012 #:phases (modify-phases %standard-phases (delete 'configure))
6015 means that all the phases described above will be used, except the
6016 @code{configure} phase.
6018 In addition, this build system ensures that the ``standard'' environment
6019 for GNU packages is available. This includes tools such as GCC, libc,
6020 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
6021 build-system gnu)} module for a complete list). We call these the
6022 @dfn{implicit inputs} of a package, because package definitions do not
6023 have to mention them.
6026 Other @code{<build-system>} objects are defined to support other
6027 conventions and tools used by free software packages. They inherit most
6028 of @code{gnu-build-system}, and differ mainly in the set of inputs
6029 implicitly added to the build process, and in the list of phases
6030 executed. Some of these build systems are listed below.
6032 @defvr {Scheme Variable} ant-build-system
6033 This variable is exported by @code{(guix build-system ant)}. It
6034 implements the build procedure for Java packages that can be built with
6035 @url{https://ant.apache.org/, Ant build tool}.
6037 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
6038 provided by the @code{icedtea} package to the set of inputs. Different
6039 packages can be specified with the @code{#:ant} and @code{#:jdk}
6040 parameters, respectively.
6042 When the original package does not provide a suitable Ant build file,
6043 the parameter @code{#:jar-name} can be used to generate a minimal Ant
6044 build file @file{build.xml} with tasks to build the specified jar
6045 archive. In this case the parameter @code{#:source-dir} can be used to
6046 specify the source sub-directory, defaulting to ``src''.
6048 The @code{#:main-class} parameter can be used with the minimal ant
6049 buildfile to specify the main class of the resulting jar. This makes the
6050 jar file executable. The @code{#:test-include} parameter can be used to
6051 specify the list of junit tests to run. It defaults to
6052 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
6053 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
6054 because abstract classes cannot be run as tests.
6056 The parameter @code{#:build-target} can be used to specify the Ant task
6057 that should be run during the @code{build} phase. By default the
6058 ``jar'' task will be run.
6062 @defvr {Scheme Variable} android-ndk-build-system
6063 @cindex Android distribution
6064 @cindex Android NDK build system
6065 This variable is exported by @code{(guix build-system android-ndk)}. It
6066 implements a build procedure for Android NDK (native development kit)
6067 packages using a Guix-specific build process.
6069 The build system assumes that packages install their public interface
6070 (header) files to the subdirectory "include" of the "out" output and
6071 their libraries to the subdirectory "lib" of the "out" output.
6073 It's also assumed that the union of all the dependencies of a package
6074 has no conflicting files.
6076 For the time being, cross-compilation is not supported - so right now
6077 the libraries and header files are assumed to be host tools.
6081 @defvr {Scheme Variable} asdf-build-system/source
6082 @defvrx {Scheme Variable} asdf-build-system/sbcl
6083 @defvrx {Scheme Variable} asdf-build-system/ecl
6085 These variables, exported by @code{(guix build-system asdf)}, implement
6086 build procedures for Common Lisp packages using
6087 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
6088 definition facility for Common Lisp programs and libraries.
6090 The @code{asdf-build-system/source} system installs the packages in
6091 source form, and can be loaded using any common lisp implementation, via
6092 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
6093 systems in the format which a particular implementation understands.
6094 These build systems can also be used to produce executable programs, or
6095 lisp images which contain a set of packages pre-loaded.
6097 The build system uses naming conventions. For binary packages, the
6098 package name should be prefixed with the lisp implementation, such as
6099 @code{sbcl-} for @code{asdf-build-system/sbcl}.
6101 Additionally, the corresponding source package should be labeled using
6102 the same convention as python packages (see @ref{Python Modules}), using
6103 the @code{cl-} prefix.
6105 For binary packages, each system should be defined as a Guix package.
6106 If one package @code{origin} contains several systems, package variants
6107 can be created in order to build all the systems. Source packages,
6108 which use @code{asdf-build-system/source}, may contain several systems.
6110 In order to create executable programs and images, the build-side
6111 procedures @code{build-program} and @code{build-image} can be used.
6112 They should be called in a build phase after the @code{create-symlinks}
6113 phase, so that the system which was just built can be used within the
6114 resulting image. @code{build-program} requires a list of Common Lisp
6115 expressions to be passed as the @code{#:entry-program} argument.
6117 If the system is not defined within its own @code{.asd} file of the same
6118 name, then the @code{#:asd-file} parameter should be used to specify
6119 which file the system is defined in. Furthermore, if the package
6120 defines a system for its tests in a separate file, it will be loaded
6121 before the tests are run if it is specified by the
6122 @code{#:test-asd-file} parameter. If it is not set, the files
6123 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
6124 and @code{test.asd} will be tried if they exist.
6126 If for some reason the package must be named in a different way than the
6127 naming conventions suggest, the @code{#:asd-system-name} parameter can
6128 be used to specify the name of the system.
6132 @defvr {Scheme Variable} cargo-build-system
6133 @cindex Rust programming language
6134 @cindex Cargo (Rust build system)
6135 This variable is exported by @code{(guix build-system cargo)}. It
6136 supports builds of packages using Cargo, the build tool of the
6137 @uref{https://www.rust-lang.org, Rust programming language}.
6139 It adds @code{rustc} and @code{cargo} to the set of inputs.
6140 A different Rust package can be specified with the @code{#:rust} parameter.
6142 Regular cargo dependencies should be added to the package definition via the
6143 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
6144 spec can be a package or a source definition. Note that the spec must
6145 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
6146 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
6147 should be added to the package definition via the
6148 @code{#:cargo-development-inputs} parameter.
6150 In its @code{configure} phase, this build system will make any source inputs
6151 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
6152 parameters available to cargo. It will also remove an included
6153 @code{Cargo.lock} file to be recreated by @code{cargo} during the
6154 @code{build} phase. The @code{install} phase installs any crate the binaries
6155 if they are defined by the crate.
6159 @defvr {Scheme Variable} copy-build-system
6160 @cindex (copy build system)
6161 This variable is exported by @code{(guix build-system copy)}. It
6162 supports builds of simple packages that don't require much compiling,
6163 mostly just moving files around.
6165 It adds much of the @code{gnu-build-system} packages to the set of
6166 inputs. Because of this, the @code{copy-build-system} does not require
6167 all the boilerplate code often needed for the
6168 @code{trivial-build-system}.
6170 To further simplify the file installation process, an
6171 @code{#:install-plan} argument is exposed to let the packager specify
6172 which files go where. The install plan is a list of @code{(@var{source}
6173 @var{target} [@var{filters}])}. @var{filters} are optional.
6176 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
6178 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
6179 @item Otherwise install @var{source} as @var{target}.
6182 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
6183 the trailing slash of @var{target} is implied with the same meaning
6186 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
6187 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
6188 @code{#:exclude-regexp}, only select files are installed depending on
6189 the filters. Each filters is specified by a list of strings.
6191 @item With @code{#:include}, install all the files which the path suffix matches
6192 at least one of the elements in the given list.
6193 @item With @code{#:include-regexp}, install all the files which the
6194 subpaths match at least one of the regular expressions in the given
6196 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
6197 are the complement of their inclusion counterpart. Without @code{#:include} flags,
6198 install all files but those matching the exclusion filters.
6199 If both inclusions and exclusions are specified, the exclusions are done
6200 on top of the inclusions.
6203 In all cases, the paths relative to @var{source} are preserved within
6210 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
6211 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
6212 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
6213 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
6214 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
6215 @file{share/my-app/sub/file}.
6216 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
6217 @file{share/my-app/file}.
6222 @cindex Clojure (programming language)
6223 @cindex simple Clojure build system
6224 @defvr {Scheme Variable} clojure-build-system
6225 This variable is exported by @code{(guix build-system clojure)}. It implements
6226 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
6227 using plain old @code{compile} in Clojure. Cross-compilation is not supported
6230 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
6231 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
6232 @code{#:zip} parameters, respectively.
6234 A list of source directories, test directories and jar names can be specified
6235 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
6236 parameters, respectively. Compile directory and main class can be specified
6237 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
6238 Other parameters are documented below.
6240 This build system is an extension of @code{ant-build-system}, but with the
6241 following phases changed:
6246 This phase calls @code{compile} in Clojure to compile source files and runs
6247 @command{jar} to create jars from both source files and compiled files
6248 according to the include list and exclude list specified in
6249 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
6250 has priority over the include list. These lists consist of symbols
6251 representing Clojure libraries or the special keyword @code{#:all} representing
6252 all Clojure libraries found under the source directories. The parameter
6253 @code{#:omit-source?} decides if source should be included into the jars.
6256 This phase runs tests according to the include list and exclude list specified
6257 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
6258 meanings are analogous to that of @code{#:aot-include} and
6259 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
6260 stands for all Clojure libraries found under the test directories. The
6261 parameter @code{#:tests?} decides if tests should be run.
6264 This phase installs all jars built previously.
6267 Apart from the above, this build system also contains an additional phase:
6272 This phase installs all top-level files with base name matching
6273 @code{%doc-regex}. A different regex can be specified with the
6274 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
6275 directories specified in @code{#:doc-dirs} are installed as well.
6279 @defvr {Scheme Variable} cmake-build-system
6280 This variable is exported by @code{(guix build-system cmake)}. It
6281 implements the build procedure for packages using the
6282 @url{https://www.cmake.org, CMake build tool}.
6284 It automatically adds the @code{cmake} package to the set of inputs.
6285 Which package is used can be specified with the @code{#:cmake}
6288 The @code{#:configure-flags} parameter is taken as a list of flags
6289 passed to the @command{cmake} command. The @code{#:build-type}
6290 parameter specifies in abstract terms the flags passed to the compiler;
6291 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
6292 debugging information''), which roughly means that code is compiled with
6293 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
6296 @defvr {Scheme Variable} dune-build-system
6297 This variable is exported by @code{(guix build-system dune)}. It
6298 supports builds of packages using @uref{https://dune.build/, Dune}, a build
6299 tool for the OCaml programming language. It is implemented as an extension
6300 of the @code{ocaml-build-system} which is described below. As such, the
6301 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
6304 It automatically adds the @code{dune} package to the set of inputs.
6305 Which package is used can be specified with the @code{#:dune}
6308 There is no @code{configure} phase because dune packages typically don't
6309 need to be configured. The @code{#:build-flags} parameter is taken as a
6310 list of flags passed to the @code{dune} command during the build.
6312 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
6313 command instead of the more recent @code{dune} command while building
6314 a package. Its default value is @code{#f}.
6316 The @code{#:package} parameter can be passed to specify a package name, which
6317 is useful when a package contains multiple packages and you want to build
6318 only one of them. This is equivalent to passing the @code{-p} argument to
6322 @defvr {Scheme Variable} go-build-system
6323 This variable is exported by @code{(guix build-system go)}. It
6324 implements a build procedure for Go packages using the standard
6325 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
6326 Go build mechanisms}.
6328 The user is expected to provide a value for the key @code{#:import-path}
6329 and, in some cases, @code{#:unpack-path}. The
6330 @url{https://golang.org/doc/code.html#ImportPaths, import path}
6331 corresponds to the file system path expected by the package's build
6332 scripts and any referring packages, and provides a unique way to
6333 refer to a Go package. It is typically based on a combination of the
6334 package source code's remote URI and file system hierarchy structure. In
6335 some cases, you will need to unpack the package's source code to a
6336 different directory structure than the one indicated by the import path,
6337 and @code{#:unpack-path} should be used in such cases.
6339 Packages that provide Go libraries should install their source code into
6340 the built output. The key @code{#:install-source?}, which defaults to
6341 @code{#t}, controls whether or not the source code is installed. It can
6342 be set to @code{#f} for packages that only provide executable files.
6345 @defvr {Scheme Variable} glib-or-gtk-build-system
6346 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
6347 is intended for use with packages making use of GLib or GTK+.
6349 This build system adds the following two phases to the ones defined by
6350 @code{gnu-build-system}:
6353 @item glib-or-gtk-wrap
6354 The phase @code{glib-or-gtk-wrap} ensures that programs in
6355 @file{bin/} are able to find GLib ``schemas'' and
6356 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
6357 modules}. This is achieved by wrapping the programs in launch scripts
6358 that appropriately set the @code{XDG_DATA_DIRS} and @code{GTK_PATH}
6359 environment variables.
6361 It is possible to exclude specific package outputs from that wrapping
6362 process by listing their names in the
6363 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
6364 when an output is known not to contain any GLib or GTK+ binaries, and
6365 where wrapping would gratuitously add a dependency of that output on
6368 @item glib-or-gtk-compile-schemas
6369 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
6370 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
6371 GSettings schemas} of GLib are compiled. Compilation is performed by the
6372 @command{glib-compile-schemas} program. It is provided by the package
6373 @code{glib:bin} which is automatically imported by the build system.
6374 The @code{glib} package providing @command{glib-compile-schemas} can be
6375 specified with the @code{#:glib} parameter.
6378 Both phases are executed after the @code{install} phase.
6381 @defvr {Scheme Variable} guile-build-system
6382 This build system is for Guile packages that consist exclusively of Scheme
6383 code and that are so lean that they don't even have a makefile, let alone a
6384 @file{configure} script. It compiles Scheme code using @command{guild
6385 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
6386 installs the @file{.scm} and @file{.go} files in the right place. It also
6387 installs documentation.
6389 This build system supports cross-compilation by using the @code{--target}
6390 option of @command{guild compile}.
6392 Packages built with @code{guile-build-system} must provide a Guile package in
6393 their @code{native-inputs} field.
6396 @defvr {Scheme Variable} julia-build-system
6397 This variable is exported by @code{(guix build-system julia)}. It implements
6398 the build procedure used by @uref{https://julialang.org/, julia} packages,
6399 which essentially is similar to running @command{julia -e 'using Pkg;
6400 Pkg.add(package)'} in an environment where @code{JULIA_LOAD_PATH} contains the
6401 paths to all Julia package inputs. Tests are run not run.
6403 Julia packages require the source @code{file-name} to be the real name of the
6404 package, correctly capitalized.
6406 For packages requiring shared library dependencies, you may need to write the
6407 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
6408 variable = /gnu/store/library.so} for each dependency, plus a void function
6409 @code{check_deps() = nothing}.
6411 Some older packages that aren't using @file{Package.toml} yet, will require
6412 this file to be created, too. The function @code{julia-create-package-toml}
6413 helps creating the file. You need to pass the outputs and the source of the
6414 package, it's name (the same as the @code{file-name} parameter), the package
6415 uuid, the package version, and a list of dependencies specified by their name
6419 @defvr {Scheme Variable} minify-build-system
6420 This variable is exported by @code{(guix build-system minify)}. It
6421 implements a minification procedure for simple JavaScript packages.
6423 It adds @code{uglify-js} to the set of inputs and uses it to compress
6424 all JavaScript files in the @file{src} directory. A different minifier
6425 package can be specified with the @code{#:uglify-js} parameter, but it
6426 is expected that the package writes the minified code to the standard
6429 When the input JavaScript files are not all located in the @file{src}
6430 directory, the parameter @code{#:javascript-files} can be used to
6431 specify a list of file names to feed to the minifier.
6434 @defvr {Scheme Variable} ocaml-build-system
6435 This variable is exported by @code{(guix build-system ocaml)}. It implements
6436 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
6437 of choosing the correct set of commands to run for each package. OCaml
6438 packages can expect many different commands to be run. This build system will
6441 When the package has a @file{setup.ml} file present at the top-level, it will
6442 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
6443 @code{ocaml setup.ml -install}. The build system will assume that this file
6444 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
6445 care of setting the prefix and enabling tests if they are not disabled. You
6446 can pass configure and build flags with the @code{#:configure-flags} and
6447 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
6448 set of flags used to enable tests. The @code{#:use-make?} key can be used to
6449 bypass this system in the build and install phases.
6451 When the package has a @file{configure} file, it is assumed that it is a
6452 hand-made configure script that requires a different argument format than
6453 in the @code{gnu-build-system}. You can add more flags with the
6454 @code{#:configure-flags} key.
6456 When the package has a @file{Makefile} file (or @code{#:use-make?} is
6457 @code{#t}), it will be used and more flags can be passed to the build and
6458 install phases with the @code{#:make-flags} key.
6460 Finally, some packages do not have these files and use a somewhat standard
6461 location for its build system. In that case, the build system will run
6462 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
6463 providing the path to the required findlib module. Additional flags can
6464 be passed via the @code{#:build-flags} key. Install is taken care of by
6465 @command{opam-installer}. In this case, the @code{opam} package must
6466 be added to the @code{native-inputs} field of the package definition.
6468 Note that most OCaml packages assume they will be installed in the same
6469 directory as OCaml, which is not what we want in guix. In particular, they
6470 will install @file{.so} files in their module's directory, which is usually
6471 fine because it is in the OCaml compiler directory. In guix though, these
6472 libraries cannot be found and we use @code{CAML_LD_LIBRARY_PATH}. This
6473 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
6474 @file{.so} libraries should be installed.
6477 @defvr {Scheme Variable} python-build-system
6478 This variable is exported by @code{(guix build-system python)}. It
6479 implements the more or less standard build procedure used by Python
6480 packages, which consists in running @code{python setup.py build} and
6481 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
6483 For packages that install stand-alone Python programs under @code{bin/},
6484 it takes care of wrapping these programs so that their @code{PYTHONPATH}
6485 environment variable points to all the Python libraries they depend on.
6487 Which Python package is used to perform the build can be specified with
6488 the @code{#:python} parameter. This is a useful way to force a package
6489 to be built for a specific version of the Python interpreter, which
6490 might be necessary if the package is only compatible with a single
6491 interpreter version.
6493 By default guix calls @code{setup.py} under control of
6494 @code{setuptools}, much like @command{pip} does. Some packages are not
6495 compatible with setuptools (and pip), thus you can disable this by
6496 setting the @code{#:use-setuptools?} parameter to @code{#f}.
6499 @defvr {Scheme Variable} perl-build-system
6500 This variable is exported by @code{(guix build-system perl)}. It
6501 implements the standard build procedure for Perl packages, which either
6502 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
6503 followed by @code{Build} and @code{Build install}; or in running
6504 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
6505 @code{make} and @code{make install}, depending on which of
6506 @code{Build.PL} or @code{Makefile.PL} is present in the package
6507 distribution. Preference is given to the former if both @code{Build.PL}
6508 and @code{Makefile.PL} exist in the package distribution. This
6509 preference can be reversed by specifying @code{#t} for the
6510 @code{#:make-maker?} parameter.
6512 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
6513 passes flags specified by the @code{#:make-maker-flags} or
6514 @code{#:module-build-flags} parameter, respectively.
6516 Which Perl package is used can be specified with @code{#:perl}.
6519 @defvr {Scheme Variable} qt-build-system
6520 This variable is exported by @code{(guix build-system qt)}. It
6521 is intended for use with applications using Qt or KDE.
6523 This build system adds the following two phases to the ones defined by
6524 @code{cmake-build-system}:
6528 The phase @code{check-setup} prepares the environment for running
6529 the checks as commonly used by Qt test programs.
6530 For now this only sets some environment variables:
6531 @code{QT_QPA_PLATFORM=offscreen},
6532 @code{DBUS_FATAL_WARNINGS=0} and
6533 @code{CTEST_OUTPUT_ON_FAILURE=1}.
6535 This phase is added before the @code{check} phase.
6536 It's a separate phase to ease adjusting if necessary.
6539 The phase @code{qt-wrap}
6540 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
6541 and output. In case some path is found, all programs in the output's
6542 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
6543 are wrapped in scripts defining the necessary environment variables.
6545 It is possible to exclude specific package outputs from that wrapping process
6546 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
6547 This is useful when an output is known not to contain any Qt binaries, and
6548 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
6551 This phase is added after the @code{install} phase.
6555 @defvr {Scheme Variable} r-build-system
6556 This variable is exported by @code{(guix build-system r)}. It
6557 implements the build procedure used by @uref{https://r-project.org, R}
6558 packages, which essentially is little more than running @code{R CMD
6559 INSTALL --library=/gnu/store/@dots{}} in an environment where
6560 @code{R_LIBS_SITE} contains the paths to all R package inputs. Tests
6561 are run after installation using the R function
6562 @code{tools::testInstalledPackage}.
6565 @defvr {Scheme Variable} rakudo-build-system
6566 This variable is exported by @code{(guix build-system rakudo)}. It
6567 implements the build procedure used by @uref{https://rakudo.org/,
6568 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
6569 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
6570 installs the binaries, library files and the resources, as well as wrap
6571 the files under the @code{bin/} directory. Tests can be skipped by
6572 passing @code{#f} to the @code{tests?} parameter.
6574 Which rakudo package is used can be specified with @code{rakudo}.
6575 Which perl6-tap-harness package used for the tests can be specified with
6576 @code{#:prove6} or removed by passing @code{#f} to the
6577 @code{with-prove6?} parameter.
6578 Which perl6-zef package used for tests and installing can be specified
6579 with @code{#:zef} or removed by passing @code{#f} to the
6580 @code{with-zef?} parameter.
6583 @defvr {Scheme Variable} texlive-build-system
6584 This variable is exported by @code{(guix build-system texlive)}. It is
6585 used to build TeX packages in batch mode with a specified engine. The
6586 build system sets the @code{TEXINPUTS} variable to find all TeX source
6587 files in the inputs.
6589 By default it runs @code{luatex} on all files ending on @code{ins}. A
6590 different engine and format can be specified with the
6591 @code{#:tex-format} argument. Different build targets can be specified
6592 with the @code{#:build-targets} argument, which expects a list of file
6593 names. The build system adds only @code{texlive-bin} and
6594 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
6595 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
6596 and @code{#:texlive-latex-base}, respectively.
6598 The @code{#:tex-directory} parameter tells the build system where to
6599 install the built files under the texmf tree.
6602 @defvr {Scheme Variable} ruby-build-system
6603 This variable is exported by @code{(guix build-system ruby)}. It
6604 implements the RubyGems build procedure used by Ruby packages, which
6605 involves running @code{gem build} followed by @code{gem install}.
6607 The @code{source} field of a package that uses this build system
6608 typically references a gem archive, since this is the format that Ruby
6609 developers use when releasing their software. The build system unpacks
6610 the gem archive, potentially patches the source, runs the test suite,
6611 repackages the gem, and installs it. Additionally, directories and
6612 tarballs may be referenced to allow building unreleased gems from Git or
6613 a traditional source release tarball.
6615 Which Ruby package is used can be specified with the @code{#:ruby}
6616 parameter. A list of additional flags to be passed to the @command{gem}
6617 command can be specified with the @code{#:gem-flags} parameter.
6620 @defvr {Scheme Variable} waf-build-system
6621 This variable is exported by @code{(guix build-system waf)}. It
6622 implements a build procedure around the @code{waf} script. The common
6623 phases---@code{configure}, @code{build}, and @code{install}---are
6624 implemented by passing their names as arguments to the @code{waf}
6627 The @code{waf} script is executed by the Python interpreter. Which
6628 Python package is used to run the script can be specified with the
6629 @code{#:python} parameter.
6632 @defvr {Scheme Variable} scons-build-system
6633 This variable is exported by @code{(guix build-system scons)}. It
6634 implements the build procedure used by the SCons software construction
6635 tool. This build system runs @code{scons} to build the package,
6636 @code{scons test} to run tests, and then @code{scons install} to install
6639 Additional flags to be passed to @code{scons} can be specified with the
6640 @code{#:scons-flags} parameter. The default build and install targets
6641 can be overridden with @code{#:build-targets} and
6642 @code{#:install-targets} respectively. The version of Python used to
6643 run SCons can be specified by selecting the appropriate SCons package
6644 with the @code{#:scons} parameter.
6647 @defvr {Scheme Variable} haskell-build-system
6648 This variable is exported by @code{(guix build-system haskell)}. It
6649 implements the Cabal build procedure used by Haskell packages, which
6650 involves running @code{runhaskell Setup.hs configure
6651 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
6652 Instead of installing the package by running @code{runhaskell Setup.hs
6653 install}, to avoid trying to register libraries in the read-only
6654 compiler store directory, the build system uses @code{runhaskell
6655 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
6656 addition, the build system generates the package documentation by
6657 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
6658 is passed. Optional Haddock parameters can be passed with the help of
6659 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
6660 not found, the build system looks for @code{Setup.lhs} instead.
6662 Which Haskell compiler is used can be specified with the @code{#:haskell}
6663 parameter which defaults to @code{ghc}.
6666 @defvr {Scheme Variable} dub-build-system
6667 This variable is exported by @code{(guix build-system dub)}. It
6668 implements the Dub build procedure used by D packages, which
6669 involves running @code{dub build} and @code{dub run}.
6670 Installation is done by copying the files manually.
6672 Which D compiler is used can be specified with the @code{#:ldc}
6673 parameter which defaults to @code{ldc}.
6676 @defvr {Scheme Variable} emacs-build-system
6677 This variable is exported by @code{(guix build-system emacs)}. It
6678 implements an installation procedure similar to the packaging system
6679 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
6681 It first creates the @code{@code{package}-autoloads.el} file, then it
6682 byte compiles all Emacs Lisp files. Differently from the Emacs
6683 packaging system, the Info documentation files are moved to the standard
6684 documentation directory and the @file{dir} file is deleted. Each
6685 package is installed in its own directory under
6686 @file{share/emacs/site-lisp/guix.d}.
6689 @defvr {Scheme Variable} font-build-system
6690 This variable is exported by @code{(guix build-system font)}. It
6691 implements an installation procedure for font packages where upstream
6692 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
6693 need to be copied into place. It copies font files to standard
6694 locations in the output directory.
6697 @defvr {Scheme Variable} meson-build-system
6698 This variable is exported by @code{(guix build-system meson)}. It
6699 implements the build procedure for packages that use
6700 @url{https://mesonbuild.com, Meson} as their build system.
6702 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
6703 of inputs, and they can be changed with the parameters @code{#:meson}
6704 and @code{#:ninja} if needed. The default Meson is
6705 @code{meson-for-build}, which is special because it doesn't clear the
6706 @code{RUNPATH} of binaries and libraries when they are installed.
6708 This build system is an extension of @code{gnu-build-system}, but with the
6709 following phases changed to some specific for Meson:
6714 The phase runs @code{meson} with the flags specified in
6715 @code{#:configure-flags}. The flag @code{--build-type} is always set to
6716 @code{plain} unless something else is specified in @code{#:build-type}.
6719 The phase runs @code{ninja} to build the package in parallel by default, but
6720 this can be changed with @code{#:parallel-build?}.
6723 The phase runs @code{ninja} with the target specified in @code{#:test-target},
6724 which is @code{"test"} by default.
6727 The phase runs @code{ninja install} and can not be changed.
6730 Apart from that, the build system also adds the following phases:
6735 This phase ensures that all binaries can find the libraries they need.
6736 It searches for required libraries in subdirectories of the package being
6737 built, and adds those to @code{RUNPATH} where needed. It also removes
6738 references to libraries left over from the build phase by
6739 @code{meson-for-build}, such as test dependencies, that aren't actually
6740 required for the program to run.
6742 @item glib-or-gtk-wrap
6743 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6744 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6746 @item glib-or-gtk-compile-schemas
6747 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
6748 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
6752 @defvr {Scheme Variable} linux-module-build-system
6753 @code{linux-module-build-system} allows building Linux kernel modules.
6755 @cindex build phases
6756 This build system is an extension of @code{gnu-build-system}, but with the
6757 following phases changed:
6762 This phase configures the environment so that the Linux kernel's Makefile
6763 can be used to build the external kernel module.
6766 This phase uses the Linux kernel's Makefile in order to build the external
6770 This phase uses the Linux kernel's Makefile in order to install the external
6774 It is possible and useful to specify the Linux kernel to use for building
6775 the module (in the "arguments" form of a package using the
6776 linux-module-build-system, use the key #:linux to specify it).
6779 @defvr {Scheme Variable} node-build-system
6780 This variable is exported by @code{(guix build-system node)}. It
6781 implements the build procedure used by @uref{http://nodejs.org,
6782 Node.js}, which implements an approximation of the @code{npm install}
6783 command, followed by an @code{npm test} command.
6785 Which Node.js package is used to interpret the @code{npm} commands can
6786 be specified with the @code{#:node} parameter which defaults to
6790 Lastly, for packages that do not need anything as sophisticated, a
6791 ``trivial'' build system is provided. It is trivial in the sense that
6792 it provides basically no support: it does not pull any implicit inputs,
6793 and does not have a notion of build phases.
6795 @defvr {Scheme Variable} trivial-build-system
6796 This variable is exported by @code{(guix build-system trivial)}.
6798 This build system requires a @code{#:builder} argument. This argument
6799 must be a Scheme expression that builds the package output(s)---as
6800 with @code{build-expression->derivation} (@pxref{Derivations,
6801 @code{build-expression->derivation}}).
6811 Conceptually, the @dfn{store} is the place where derivations that have
6812 been built successfully are stored---by default, @file{/gnu/store}.
6813 Sub-directories in the store are referred to as @dfn{store items} or
6814 sometimes @dfn{store paths}. The store has an associated database that
6815 contains information such as the store paths referred to by each store
6816 path, and the list of @emph{valid} store items---results of successful
6817 builds. This database resides in @file{@var{localstatedir}/guix/db},
6818 where @var{localstatedir} is the state directory specified @i{via}
6819 @option{--localstatedir} at configure time, usually @file{/var}.
6821 The store is @emph{always} accessed by the daemon on behalf of its clients
6822 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
6823 connect to the daemon over a Unix-domain socket, send requests to it,
6824 and read the result---these are remote procedure calls, or RPCs.
6827 Users must @emph{never} modify files under @file{/gnu/store} directly.
6828 This would lead to inconsistencies and break the immutability
6829 assumptions of Guix's functional model (@pxref{Introduction}).
6831 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
6832 how to check the integrity of the store and attempt recovery from
6833 accidental modifications.
6836 The @code{(guix store)} module provides procedures to connect to the
6837 daemon, and to perform RPCs. These are described below. By default,
6838 @code{open-connection}, and thus all the @command{guix} commands,
6839 connect to the local daemon or to the URI specified by the
6840 @code{GUIX_DAEMON_SOCKET} environment variable.
6842 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
6843 When set, the value of this variable should be a file name or a URI
6844 designating the daemon endpoint. When it is a file name, it denotes a
6845 Unix-domain socket to connect to. In addition to file names, the
6846 supported URI schemes are:
6851 These are for Unix-domain sockets.
6852 @code{file:///var/guix/daemon-socket/socket} is equivalent to
6853 @file{/var/guix/daemon-socket/socket}.
6856 @cindex daemon, remote access
6857 @cindex remote access to the daemon
6858 @cindex daemon, cluster setup
6859 @cindex clusters, daemon setup
6860 These URIs denote connections over TCP/IP, without encryption nor
6861 authentication of the remote host. The URI must specify the host name
6862 and optionally a port number (by default port 44146 is used):
6865 guix://master.guix.example.org:1234
6868 This setup is suitable on local networks, such as clusters, where only
6869 trusted nodes may connect to the build daemon at
6870 @code{master.guix.example.org}.
6872 The @code{--listen} option of @command{guix-daemon} can be used to
6873 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
6877 @cindex SSH access to build daemons
6878 These URIs allow you to connect to a remote daemon over SSH. This
6879 feature requires Guile-SSH (@pxref{Requirements}) and a working
6880 @code{guile} binary in @code{PATH} on the destination machine. It
6881 supports public key and GSSAPI authentication. A typical URL might look
6885 ssh://charlie@@guix.example.org:22
6888 As for @command{guix copy}, the usual OpenSSH client configuration files
6889 are honored (@pxref{Invoking guix copy}).
6892 Additional URI schemes may be supported in the future.
6894 @c XXX: Remove this note when the protocol incurs fewer round trips
6895 @c and when (guix derivations) no longer relies on file system access.
6897 The ability to connect to remote build daemons is considered
6898 experimental as of @value{VERSION}. Please get in touch with us to
6899 share any problems or suggestions you may have (@pxref{Contributing}).
6903 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
6904 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
6905 @var{reserve-space?} is true, instruct it to reserve a little bit of
6906 extra space on the file system so that the garbage collector can still
6907 operate should the disk become full. Return a server object.
6909 @var{file} defaults to @code{%default-socket-path}, which is the normal
6910 location given the options that were passed to @command{configure}.
6913 @deffn {Scheme Procedure} close-connection @var{server}
6914 Close the connection to @var{server}.
6917 @defvr {Scheme Variable} current-build-output-port
6918 This variable is bound to a SRFI-39 parameter, which refers to the port
6919 where build and error logs sent by the daemon should be written.
6922 Procedures that make RPCs all take a server object as their first
6925 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
6926 @cindex invalid store items
6927 Return @code{#t} when @var{path} designates a valid store item and
6928 @code{#f} otherwise (an invalid item may exist on disk but still be
6929 invalid, for instance because it is the result of an aborted or failed
6932 A @code{&store-protocol-error} condition is raised if @var{path} is not
6933 prefixed by the store directory (@file{/gnu/store}).
6936 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
6937 Add @var{text} under file @var{name} in the store, and return its store
6938 path. @var{references} is the list of store paths referred to by the
6939 resulting store path.
6942 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
6944 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
6945 file names, or derivation/output pairs, using the specified
6946 @var{mode}---@code{(build-mode normal)} by default.
6949 Note that the @code{(guix monads)} module provides a monad as well as
6950 monadic versions of the above procedures, with the goal of making it
6951 more convenient to work with code that accesses the store (@pxref{The
6955 @i{This section is currently incomplete.}
6958 @section Derivations
6961 Low-level build actions and the environment in which they are performed
6962 are represented by @dfn{derivations}. A derivation contains the
6963 following pieces of information:
6967 The outputs of the derivation---derivations produce at least one file or
6968 directory in the store, but may produce more.
6971 @cindex build-time dependencies
6972 @cindex dependencies, build-time
6973 The inputs of the derivations---i.e., its build-time dependencies---which may
6974 be other derivations or plain files in the store (patches, build scripts,
6978 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
6981 The file name of a build script in the store, along with the arguments
6985 A list of environment variables to be defined.
6989 @cindex derivation path
6990 Derivations allow clients of the daemon to communicate build actions to
6991 the store. They exist in two forms: as an in-memory representation,
6992 both on the client- and daemon-side, and as files in the store whose
6993 name end in @code{.drv}---these files are referred to as @dfn{derivation
6994 paths}. Derivations paths can be passed to the @code{build-derivations}
6995 procedure to perform the build actions they prescribe (@pxref{The
6998 @cindex fixed-output derivations
6999 Operations such as file downloads and version-control checkouts for
7000 which the expected content hash is known in advance are modeled as
7001 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
7002 of a fixed-output derivation are independent of its inputs---e.g., a
7003 source code download produces the same result regardless of the download
7004 method and tools being used.
7007 @cindex run-time dependencies
7008 @cindex dependencies, run-time
7009 The outputs of derivations---i.e., the build results---have a set of
7010 @dfn{references}, as reported by the @code{references} RPC or the
7011 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
7012 are the set of run-time dependencies of the build results. References are a
7013 subset of the inputs of the derivation; this subset is automatically computed
7014 by the build daemon by scanning all the files in the outputs.
7016 The @code{(guix derivations)} module provides a representation of
7017 derivations as Scheme objects, along with procedures to create and
7018 otherwise manipulate derivations. The lowest-level primitive to create
7019 a derivation is the @code{derivation} procedure:
7021 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
7022 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7023 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
7024 [#:system (%current-system)] [#:references-graphs #f] @
7025 [#:allowed-references #f] [#:disallowed-references #f] @
7026 [#:leaked-env-vars #f] [#:local-build? #f] @
7027 [#:substitutable? #t] [#:properties '()]
7028 Build a derivation with the given arguments, and return the resulting
7029 @code{<derivation>} object.
7031 When @var{hash} and @var{hash-algo} are given, a
7032 @dfn{fixed-output derivation} is created---i.e., one whose result is
7033 known in advance, such as a file download. If, in addition,
7034 @var{recursive?} is true, then that fixed output may be an executable
7035 file or a directory and @var{hash} must be the hash of an archive
7036 containing this output.
7038 When @var{references-graphs} is true, it must be a list of file
7039 name/store path pairs. In that case, the reference graph of each store
7040 path is exported in the build environment in the corresponding file, in
7041 a simple text format.
7043 When @var{allowed-references} is true, it must be a list of store items
7044 or outputs that the derivation's output may refer to. Likewise,
7045 @var{disallowed-references}, if true, must be a list of things the
7046 outputs may @emph{not} refer to.
7048 When @var{leaked-env-vars} is true, it must be a list of strings
7049 denoting environment variables that are allowed to ``leak'' from the
7050 daemon's environment to the build environment. This is only applicable
7051 to fixed-output derivations---i.e., when @var{hash} is true. The main
7052 use is to allow variables such as @code{http_proxy} to be passed to
7053 derivations that download files.
7055 When @var{local-build?} is true, declare that the derivation is not a
7056 good candidate for offloading and should rather be built locally
7057 (@pxref{Daemon Offload Setup}). This is the case for small derivations
7058 where the costs of data transfers would outweigh the benefits.
7060 When @var{substitutable?} is false, declare that substitutes of the
7061 derivation's output should not be used (@pxref{Substitutes}). This is
7062 useful, for instance, when building packages that capture details of the
7063 host CPU instruction set.
7065 @var{properties} must be an association list describing ``properties'' of the
7066 derivation. It is kept as-is, uninterpreted, in the derivation.
7070 Here's an example with a shell script as its builder, assuming
7071 @var{store} is an open connection to the daemon, and @var{bash} points
7072 to a Bash executable in the store:
7075 (use-modules (guix utils)
7079 (let ((builder ; add the Bash script to the store
7080 (add-text-to-store store "my-builder.sh"
7081 "echo hello world > $out\n" '())))
7082 (derivation store "foo"
7083 bash `("-e" ,builder)
7084 #:inputs `((,bash) (,builder))
7085 #:env-vars '(("HOME" . "/homeless"))))
7086 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
7089 As can be guessed, this primitive is cumbersome to use directly. A
7090 better approach is to write build scripts in Scheme, of course! The
7091 best course of action for that is to write the build code as a
7092 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
7093 information, @pxref{G-Expressions}.
7095 Once upon a time, @code{gexp->derivation} did not exist and constructing
7096 derivations with build code written in Scheme was achieved with
7097 @code{build-expression->derivation}, documented below. This procedure
7098 is now deprecated in favor of the much nicer @code{gexp->derivation}.
7100 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
7101 @var{name} @var{exp} @
7102 [#:system (%current-system)] [#:inputs '()] @
7103 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
7104 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7105 [#:references-graphs #f] [#:allowed-references #f] @
7106 [#:disallowed-references #f] @
7107 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
7108 Return a derivation that executes Scheme expression @var{exp} as a
7109 builder for derivation @var{name}. @var{inputs} must be a list of
7110 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
7111 @code{"out"} is assumed. @var{modules} is a list of names of Guile
7112 modules from the current search path to be copied in the store,
7113 compiled, and made available in the load path during the execution of
7114 @var{exp}---e.g., @code{((guix build utils) (guix build
7115 gnu-build-system))}.
7117 @var{exp} is evaluated in an environment where @code{%outputs} is bound
7118 to a list of output/path pairs, and where @code{%build-inputs} is bound
7119 to a list of string/output-path pairs made from @var{inputs}.
7120 Optionally, @var{env-vars} is a list of string pairs specifying the name
7121 and value of environment variables visible to the builder. The builder
7122 terminates by passing the result of @var{exp} to @code{exit}; thus, when
7123 @var{exp} returns @code{#f}, the build is considered to have failed.
7125 @var{exp} is built using @var{guile-for-build} (a derivation). When
7126 @var{guile-for-build} is omitted or is @code{#f}, the value of the
7127 @code{%guile-for-build} fluid is used instead.
7129 See the @code{derivation} procedure for the meaning of
7130 @var{references-graphs}, @var{allowed-references},
7131 @var{disallowed-references}, @var{local-build?}, and
7132 @var{substitutable?}.
7136 Here's an example of a single-output derivation that creates a directory
7137 containing one file:
7140 (let ((builder '(let ((out (assoc-ref %outputs "out")))
7141 (mkdir out) ; create /gnu/store/@dots{}-goo
7142 (call-with-output-file (string-append out "/test")
7144 (display '(hello guix) p))))))
7145 (build-expression->derivation store "goo" builder))
7147 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
7151 @node The Store Monad
7152 @section The Store Monad
7156 The procedures that operate on the store described in the previous
7157 sections all take an open connection to the build daemon as their first
7158 argument. Although the underlying model is functional, they either have
7159 side effects or depend on the current state of the store.
7161 The former is inconvenient: the connection to the build daemon has to be
7162 carried around in all those functions, making it impossible to compose
7163 functions that do not take that parameter with functions that do. The
7164 latter can be problematic: since store operations have side effects
7165 and/or depend on external state, they have to be properly sequenced.
7167 @cindex monadic values
7168 @cindex monadic functions
7169 This is where the @code{(guix monads)} module comes in. This module
7170 provides a framework for working with @dfn{monads}, and a particularly
7171 useful monad for our uses, the @dfn{store monad}. Monads are a
7172 construct that allows two things: associating ``context'' with values
7173 (in our case, the context is the store), and building sequences of
7174 computations (here computations include accesses to the store). Values
7175 in a monad---values that carry this additional context---are called
7176 @dfn{monadic values}; procedures that return such values are called
7177 @dfn{monadic procedures}.
7179 Consider this ``normal'' procedure:
7182 (define (sh-symlink store)
7183 ;; Return a derivation that symlinks the 'bash' executable.
7184 (let* ((drv (package-derivation store bash))
7185 (out (derivation->output-path drv))
7186 (sh (string-append out "/bin/bash")))
7187 (build-expression->derivation store "sh"
7188 `(symlink ,sh %output))))
7191 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
7192 as a monadic function:
7195 (define (sh-symlink)
7196 ;; Same, but return a monadic value.
7197 (mlet %store-monad ((drv (package->derivation bash)))
7198 (gexp->derivation "sh"
7199 #~(symlink (string-append #$drv "/bin/bash")
7203 There are several things to note in the second version: the @code{store}
7204 parameter is now implicit and is ``threaded'' in the calls to the
7205 @code{package->derivation} and @code{gexp->derivation} monadic
7206 procedures, and the monadic value returned by @code{package->derivation}
7207 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
7209 As it turns out, the call to @code{package->derivation} can even be
7210 omitted since it will take place implicitly, as we will see later
7211 (@pxref{G-Expressions}):
7214 (define (sh-symlink)
7215 (gexp->derivation "sh"
7216 #~(symlink (string-append #$bash "/bin/bash")
7221 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
7222 @c for the funny quote.
7223 Calling the monadic @code{sh-symlink} has no effect. As someone once
7224 said, ``you exit a monad like you exit a building on fire: by running''.
7225 So, to exit the monad and get the desired effect, one must use
7226 @code{run-with-store}:
7229 (run-with-store (open-connection) (sh-symlink))
7230 @result{} /gnu/store/...-sh-symlink
7233 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
7234 new ``meta-commands'' to make it easier to deal with monadic procedures:
7235 @code{run-in-store}, and @code{enter-store-monad}. The former is used
7236 to ``run'' a single monadic value through the store:
7239 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
7240 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7243 The latter enters a recursive REPL, where all the return values are
7244 automatically run through the store:
7247 scheme@@(guile-user)> ,enter-store-monad
7248 store-monad@@(guile-user) [1]> (package->derivation hello)
7249 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
7250 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
7251 $3 = "/gnu/store/@dots{}-foo"
7252 store-monad@@(guile-user) [1]> ,q
7253 scheme@@(guile-user)>
7257 Note that non-monadic values cannot be returned in the
7258 @code{store-monad} REPL.
7260 The main syntactic forms to deal with monads in general are provided by
7261 the @code{(guix monads)} module and are described below.
7263 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
7264 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
7268 @deffn {Scheme Syntax} return @var{val}
7269 Return a monadic value that encapsulates @var{val}.
7272 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
7273 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
7274 procedures @var{mproc}@dots{}@footnote{This operation is commonly
7275 referred to as ``bind'', but that name denotes an unrelated procedure in
7276 Guile. Thus we use this somewhat cryptic symbol inherited from the
7277 Haskell language.}. There can be one @var{mproc} or several of them, as
7282 (with-monad %state-monad
7284 (lambda (x) (return (+ 1 x)))
7285 (lambda (x) (return (* 2 x)))))
7289 @result{} some-state
7293 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
7295 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
7297 Bind the variables @var{var} to the monadic values @var{mval} in
7298 @var{body}, which is a sequence of expressions. As with the bind
7299 operator, this can be thought of as ``unpacking'' the raw, non-monadic
7300 value ``contained'' in @var{mval} and making @var{var} refer to that
7301 raw, non-monadic value within the scope of the @var{body}. The form
7302 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
7303 @var{val}, as per @code{let}. The binding operations occur in sequence
7304 from left to right. The last expression of @var{body} must be a monadic
7305 expression, and its result will become the result of the @code{mlet} or
7306 @code{mlet*} when run in the @var{monad}.
7308 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
7309 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
7312 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
7313 Bind @var{mexp} and the following monadic expressions in sequence,
7314 returning the result of the last expression. Every expression in the
7315 sequence must be a monadic expression.
7317 This is akin to @code{mlet}, except that the return values of the
7318 monadic expressions are ignored. In that sense, it is analogous to
7319 @code{begin}, but applied to monadic expressions.
7322 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
7323 When @var{condition} is true, evaluate the sequence of monadic
7324 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7325 @var{condition} is false, return @code{*unspecified*} in the current
7326 monad. Every expression in the sequence must be a monadic expression.
7329 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
7330 When @var{condition} is false, evaluate the sequence of monadic
7331 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
7332 @var{condition} is true, return @code{*unspecified*} in the current
7333 monad. Every expression in the sequence must be a monadic expression.
7337 The @code{(guix monads)} module provides the @dfn{state monad}, which
7338 allows an additional value---the state---to be @emph{threaded} through
7339 monadic procedure calls.
7341 @defvr {Scheme Variable} %state-monad
7342 The state monad. Procedures in the state monad can access and change
7343 the state that is threaded.
7345 Consider the example below. The @code{square} procedure returns a value
7346 in the state monad. It returns the square of its argument, but also
7347 increments the current state value:
7351 (mlet %state-monad ((count (current-state)))
7352 (mbegin %state-monad
7353 (set-current-state (+ 1 count))
7356 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
7361 When ``run'' through @var{%state-monad}, we obtain that additional state
7362 value, which is the number of @code{square} calls.
7365 @deffn {Monadic Procedure} current-state
7366 Return the current state as a monadic value.
7369 @deffn {Monadic Procedure} set-current-state @var{value}
7370 Set the current state to @var{value} and return the previous state as a
7374 @deffn {Monadic Procedure} state-push @var{value}
7375 Push @var{value} to the current state, which is assumed to be a list,
7376 and return the previous state as a monadic value.
7379 @deffn {Monadic Procedure} state-pop
7380 Pop a value from the current state and return it as a monadic value.
7381 The state is assumed to be a list.
7384 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
7385 Run monadic value @var{mval} starting with @var{state} as the initial
7386 state. Return two values: the resulting value, and the resulting state.
7389 The main interface to the store monad, provided by the @code{(guix
7390 store)} module, is as follows.
7392 @defvr {Scheme Variable} %store-monad
7393 The store monad---an alias for @var{%state-monad}.
7395 Values in the store monad encapsulate accesses to the store. When its
7396 effect is needed, a value of the store monad must be ``evaluated'' by
7397 passing it to the @code{run-with-store} procedure (see below.)
7400 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
7401 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
7402 open store connection.
7405 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
7406 Return as a monadic value the absolute file name in the store of the file
7407 containing @var{text}, a string. @var{references} is a list of store items that the
7408 resulting text file refers to; it defaults to the empty list.
7411 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
7412 Return as a monadic value the absolute file name in the store of the file
7413 containing @var{data}, a bytevector. @var{references} is a list of store
7414 items that the resulting binary file refers to; it defaults to the empty list.
7417 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
7418 [#:recursive? #t] [#:select? (const #t)]
7419 Return the name of @var{file} once interned in the store. Use
7420 @var{name} as its store name, or the basename of @var{file} if
7421 @var{name} is omitted.
7423 When @var{recursive?} is true, the contents of @var{file} are added
7424 recursively; if @var{file} designates a flat file and @var{recursive?}
7425 is true, its contents are added, and its permission bits are kept.
7427 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7428 @var{stat})} for each directory entry, where @var{file} is the entry's
7429 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7430 entries for which @var{select?} does not return true.
7432 The example below adds a file to the store, under two different names:
7435 (run-with-store (open-connection)
7436 (mlet %store-monad ((a (interned-file "README"))
7437 (b (interned-file "README" "LEGU-MIN")))
7438 (return (list a b))))
7440 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
7445 The @code{(guix packages)} module exports the following package-related
7448 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
7449 [#:system (%current-system)] [#:target #f] @
7452 value in the absolute file name of @var{file} within the @var{output}
7453 directory of @var{package}. When @var{file} is omitted, return the name
7454 of the @var{output} directory of @var{package}. When @var{target} is
7455 true, use it as a cross-compilation target triplet.
7458 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
7459 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
7460 @var{target} [@var{system}]
7461 Monadic version of @code{package-derivation} and
7462 @code{package-cross-derivation} (@pxref{Defining Packages}).
7467 @section G-Expressions
7469 @cindex G-expression
7470 @cindex build code quoting
7471 So we have ``derivations'', which represent a sequence of build actions
7472 to be performed to produce an item in the store (@pxref{Derivations}).
7473 These build actions are performed when asking the daemon to actually
7474 build the derivations; they are run by the daemon in a container
7475 (@pxref{Invoking guix-daemon}).
7477 @cindex strata of code
7478 It should come as no surprise that we like to write these build actions
7479 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
7480 code@footnote{The term @dfn{stratum} in this context was coined by
7481 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
7482 Kiselyov, who has written insightful
7483 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
7484 on this topic}, refers to this kind of code generation as
7485 @dfn{staging}.}: the ``host code''---code that defines packages, talks
7486 to the daemon, etc.---and the ``build code''---code that actually
7487 performs build actions, such as making directories, invoking
7488 @command{make}, etc.
7490 To describe a derivation and its build actions, one typically needs to
7491 embed build code inside host code. It boils down to manipulating build
7492 code as data, and the homoiconicity of Scheme---code has a direct
7493 representation as data---comes in handy for that. But we need more than
7494 the normal @code{quasiquote} mechanism in Scheme to construct build
7497 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
7498 S-expressions adapted to build expressions. G-expressions, or
7499 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
7500 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
7501 @code{#$}, and @code{#$@@}), which are comparable to
7502 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
7503 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
7504 GNU Guile Reference Manual}). However, there are major differences:
7508 Gexps are meant to be written to a file and run or manipulated by other
7512 When a high-level object such as a package or derivation is unquoted
7513 inside a gexp, the result is as if its output file name had been
7517 Gexps carry information about the packages or derivations they refer to,
7518 and these dependencies are automatically added as inputs to the build
7519 processes that use them.
7522 @cindex lowering, of high-level objects in gexps
7523 This mechanism is not limited to package and derivation
7524 objects: @dfn{compilers} able to ``lower'' other high-level objects to
7525 derivations or files in the store can be defined,
7526 such that these objects can also be inserted
7527 into gexps. For example, a useful type of high-level objects that can be
7528 inserted in a gexp is ``file-like objects'', which make it easy to
7529 add files to the store and to refer to them in
7530 derivations and such (see @code{local-file} and @code{plain-file}
7533 To illustrate the idea, here is an example of a gexp:
7540 (symlink (string-append #$coreutils "/bin/ls")
7544 This gexp can be passed to @code{gexp->derivation}; we obtain a
7545 derivation that builds a directory containing exactly one symlink to
7546 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
7549 (gexp->derivation "the-thing" build-exp)
7552 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
7553 substituted to the reference to the @var{coreutils} package in the
7554 actual build code, and @var{coreutils} is automatically made an input to
7555 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
7556 output)}) is replaced by a string containing the directory name of the
7557 output of the derivation.
7559 @cindex cross compilation
7560 In a cross-compilation context, it is useful to distinguish between
7561 references to the @emph{native} build of a package---that can run on the
7562 host---versus references to cross builds of a package. To that end, the
7563 @code{#+} plays the same role as @code{#$}, but is a reference to a
7564 native package build:
7567 (gexp->derivation "vi"
7570 (mkdir (string-append #$output "/bin"))
7571 (system* (string-append #+coreutils "/bin/ln")
7573 (string-append #$emacs "/bin/emacs")
7574 (string-append #$output "/bin/vi")))
7575 #:target "mips64el-linux-gnu")
7579 In the example above, the native build of @var{coreutils} is used, so
7580 that @command{ln} can actually run on the host; but then the
7581 cross-compiled build of @var{emacs} is referenced.
7583 @cindex imported modules, for gexps
7584 @findex with-imported-modules
7585 Another gexp feature is @dfn{imported modules}: sometimes you want to be
7586 able to use certain Guile modules from the ``host environment'' in the
7587 gexp, so those modules should be imported in the ``build environment''.
7588 The @code{with-imported-modules} form allows you to express that:
7591 (let ((build (with-imported-modules '((guix build utils))
7593 (use-modules (guix build utils))
7594 (mkdir-p (string-append #$output "/bin"))))))
7595 (gexp->derivation "empty-dir"
7598 (display "success!\n")
7603 In this example, the @code{(guix build utils)} module is automatically
7604 pulled into the isolated build environment of our gexp, such that
7605 @code{(use-modules (guix build utils))} works as expected.
7607 @cindex module closure
7608 @findex source-module-closure
7609 Usually you want the @emph{closure} of the module to be imported---i.e.,
7610 the module itself and all the modules it depends on---rather than just
7611 the module; failing to do that, attempts to use the module will fail
7612 because of missing dependent modules. The @code{source-module-closure}
7613 procedure computes the closure of a module by looking at its source file
7614 headers, which comes in handy in this case:
7617 (use-modules (guix modules)) ;for 'source-module-closure'
7619 (with-imported-modules (source-module-closure
7620 '((guix build utils)
7622 (gexp->derivation "something-with-vms"
7624 (use-modules (guix build utils)
7629 @cindex extensions, for gexps
7630 @findex with-extensions
7631 In the same vein, sometimes you want to import not just pure-Scheme
7632 modules, but also ``extensions'' such as Guile bindings to C libraries
7633 or other ``full-blown'' packages. Say you need the @code{guile-json}
7634 package available on the build side, here's how you would do it:
7637 (use-modules (gnu packages guile)) ;for 'guile-json'
7639 (with-extensions (list guile-json)
7640 (gexp->derivation "something-with-json"
7642 (use-modules (json))
7646 The syntactic form to construct gexps is summarized below.
7648 @deffn {Scheme Syntax} #~@var{exp}
7649 @deffnx {Scheme Syntax} (gexp @var{exp})
7650 Return a G-expression containing @var{exp}. @var{exp} may contain one
7651 or more of the following forms:
7655 @itemx (ungexp @var{obj})
7656 Introduce a reference to @var{obj}. @var{obj} may have one of the
7657 supported types, for example a package or a
7658 derivation, in which case the @code{ungexp} form is replaced by its
7659 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
7661 If @var{obj} is a list, it is traversed and references to supported
7662 objects are substituted similarly.
7664 If @var{obj} is another gexp, its contents are inserted and its
7665 dependencies are added to those of the containing gexp.
7667 If @var{obj} is another kind of object, it is inserted as is.
7669 @item #$@var{obj}:@var{output}
7670 @itemx (ungexp @var{obj} @var{output})
7671 This is like the form above, but referring explicitly to the
7672 @var{output} of @var{obj}---this is useful when @var{obj} produces
7673 multiple outputs (@pxref{Packages with Multiple Outputs}).
7676 @itemx #+@var{obj}:output
7677 @itemx (ungexp-native @var{obj})
7678 @itemx (ungexp-native @var{obj} @var{output})
7679 Same as @code{ungexp}, but produces a reference to the @emph{native}
7680 build of @var{obj} when used in a cross compilation context.
7682 @item #$output[:@var{output}]
7683 @itemx (ungexp output [@var{output}])
7684 Insert a reference to derivation output @var{output}, or to the main
7685 output when @var{output} is omitted.
7687 This only makes sense for gexps passed to @code{gexp->derivation}.
7690 @itemx (ungexp-splicing @var{lst})
7691 Like the above, but splices the contents of @var{lst} inside the
7695 @itemx (ungexp-native-splicing @var{lst})
7696 Like the above, but refers to native builds of the objects listed in
7701 G-expressions created by @code{gexp} or @code{#~} are run-time objects
7702 of the @code{gexp?} type (see below.)
7705 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
7706 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
7707 in their execution environment.
7709 Each item in @var{modules} can be the name of a module, such as
7710 @code{(guix build utils)}, or it can be a module name, followed by an
7711 arrow, followed by a file-like object:
7714 `((guix build utils)
7716 ((guix config) => ,(scheme-file "config.scm"
7717 #~(define-module @dots{}))))
7721 In the example above, the first two modules are taken from the search
7722 path, and the last one is created from the given file-like object.
7724 This form has @emph{lexical} scope: it has an effect on the gexps
7725 directly defined in @var{body}@dots{}, but not on those defined, say, in
7726 procedures called from @var{body}@dots{}.
7729 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
7730 Mark the gexps defined in @var{body}@dots{} as requiring
7731 @var{extensions} in their build and execution environment.
7732 @var{extensions} is typically a list of package objects such as those
7733 defined in the @code{(gnu packages guile)} module.
7735 Concretely, the packages listed in @var{extensions} are added to the
7736 load path while compiling imported modules in @var{body}@dots{}; they
7737 are also added to the load path of the gexp returned by
7741 @deffn {Scheme Procedure} gexp? @var{obj}
7742 Return @code{#t} if @var{obj} is a G-expression.
7745 G-expressions are meant to be written to disk, either as code building
7746 some derivation, or as plain files in the store. The monadic procedures
7747 below allow you to do that (@pxref{The Store Monad}, for more
7748 information about monads.)
7750 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
7751 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
7752 [#:hash #f] [#:hash-algo #f] @
7753 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
7754 [#:module-path @var{%load-path}] @
7755 [#:effective-version "2.2"] @
7756 [#:references-graphs #f] [#:allowed-references #f] @
7757 [#:disallowed-references #f] @
7758 [#:leaked-env-vars #f] @
7759 [#:script-name (string-append @var{name} "-builder")] @
7760 [#:deprecation-warnings #f] @
7761 [#:local-build? #f] [#:substitutable? #t] @
7762 [#:properties '()] [#:guile-for-build #f]
7763 Return a derivation @var{name} that runs @var{exp} (a gexp) with
7764 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
7765 stored in a file called @var{script-name}. When @var{target} is true,
7766 it is used as the cross-compilation target triplet for packages referred
7769 @var{modules} is deprecated in favor of @code{with-imported-modules}.
7771 make @var{modules} available in the evaluation context of @var{exp};
7772 @var{modules} is a list of names of Guile modules searched in
7773 @var{module-path} to be copied in the store, compiled, and made available in
7774 the load path during the execution of @var{exp}---e.g., @code{((guix
7775 build utils) (guix build gnu-build-system))}.
7777 @var{effective-version} determines the string to use when adding extensions of
7778 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
7780 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
7783 When @var{references-graphs} is true, it must be a list of tuples of one of the
7787 (@var{file-name} @var{package})
7788 (@var{file-name} @var{package} @var{output})
7789 (@var{file-name} @var{derivation})
7790 (@var{file-name} @var{derivation} @var{output})
7791 (@var{file-name} @var{store-item})
7794 The right-hand-side of each element of @var{references-graphs} is automatically made
7795 an input of the build process of @var{exp}. In the build environment, each
7796 @var{file-name} contains the reference graph of the corresponding item, in a simple
7799 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
7800 In the latter case, the list denotes store items that the result is allowed to
7801 refer to. Any reference to another store item will lead to a build error.
7802 Similarly for @var{disallowed-references}, which can list items that must not be
7803 referenced by the outputs.
7805 @var{deprecation-warnings} determines whether to show deprecation warnings while
7806 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
7808 The other arguments are as for @code{derivation} (@pxref{Derivations}).
7811 @cindex file-like objects
7812 The @code{local-file}, @code{plain-file}, @code{computed-file},
7813 @code{program-file}, and @code{scheme-file} procedures below return
7814 @dfn{file-like objects}. That is, when unquoted in a G-expression,
7815 these objects lead to a file in the store. Consider this G-expression:
7818 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
7819 #$(local-file "/tmp/my-nscd.conf"))
7822 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
7823 to the store. Once expanded, for instance @i{via}
7824 @code{gexp->derivation}, the G-expression refers to that copy under
7825 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
7826 does not have any effect on what the G-expression does.
7827 @code{plain-file} can be used similarly; it differs in that the file
7828 content is directly passed as a string.
7830 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
7831 [#:recursive? #f] [#:select? (const #t)]
7832 Return an object representing local file @var{file} to add to the store;
7833 this object can be used in a gexp. If @var{file} is a literal string
7834 denoting a relative file name, it is looked up relative to the source
7835 file where it appears; if @var{file} is not a literal string, it is
7836 looked up relative to the current working directory at run time.
7837 @var{file} will be added to the store under @var{name}--by default the
7838 base name of @var{file}.
7840 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
7841 designates a flat file and @var{recursive?} is true, its contents are added, and its
7842 permission bits are kept.
7844 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
7845 @var{stat})} for each directory entry, where @var{file} is the entry's
7846 absolute file name and @var{stat} is the result of @code{lstat}; exclude
7847 entries for which @var{select?} does not return true.
7849 This is the declarative counterpart of the @code{interned-file} monadic
7850 procedure (@pxref{The Store Monad, @code{interned-file}}).
7853 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
7854 Return an object representing a text file called @var{name} with the given
7855 @var{content} (a string or a bytevector) to be added to the store.
7857 This is the declarative counterpart of @code{text-file}.
7860 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
7861 [#:options '(#:local-build? #t)]
7862 Return an object representing the store item @var{name}, a file or
7863 directory computed by @var{gexp}. @var{options}
7864 is a list of additional arguments to pass to @code{gexp->derivation}.
7866 This is the declarative counterpart of @code{gexp->derivation}.
7869 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
7870 [#:guile (default-guile)] [#:module-path %load-path] @
7871 [#:system (%current-system)] [#:target #f]
7872 Return an executable script @var{name} that runs @var{exp} using
7873 @var{guile}, with @var{exp}'s imported modules in its search path.
7874 Look up @var{exp}'s modules in @var{module-path}.
7876 The example below builds a script that simply invokes the @command{ls}
7880 (use-modules (guix gexp) (gnu packages base))
7882 (gexp->script "list-files"
7883 #~(execl #$(file-append coreutils "/bin/ls")
7887 When ``running'' it through the store (@pxref{The Store Monad,
7888 @code{run-with-store}}), we obtain a derivation that produces an
7889 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
7892 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
7894 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
7898 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
7899 [#:guile #f] [#:module-path %load-path]
7900 Return an object representing the executable store item @var{name} that
7901 runs @var{gexp}. @var{guile} is the Guile package used to execute that
7902 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
7904 This is the declarative counterpart of @code{gexp->script}.
7907 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
7908 [#:set-load-path? #t] [#:module-path %load-path] @
7910 [#:guile (default-guile)]
7911 Return a derivation that builds a file @var{name} containing @var{exp}.
7912 When @var{splice?} is true, @var{exp} is considered to be a list of
7913 expressions that will be spliced in the resulting file.
7915 When @var{set-load-path?} is true, emit code in the resulting file to
7916 set @code{%load-path} and @code{%load-compiled-path} to honor
7917 @var{exp}'s imported modules. Look up @var{exp}'s modules in
7920 The resulting file holds references to all the dependencies of @var{exp}
7921 or a subset thereof.
7924 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} [#:splice? #f]
7925 Return an object representing the Scheme file @var{name} that contains
7928 This is the declarative counterpart of @code{gexp->file}.
7931 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
7932 Return as a monadic value a derivation that builds a text file
7933 containing all of @var{text}. @var{text} may list, in addition to
7934 strings, objects of any type that can be used in a gexp: packages,
7935 derivations, local file objects, etc. The resulting store file holds
7936 references to all these.
7938 This variant should be preferred over @code{text-file} anytime the file
7939 to create will reference items from the store. This is typically the
7940 case when building a configuration file that embeds store file names,
7944 (define (profile.sh)
7945 ;; Return the name of a shell script in the store that
7946 ;; initializes the 'PATH' environment variable.
7947 (text-file* "profile.sh"
7948 "export PATH=" coreutils "/bin:"
7949 grep "/bin:" sed "/bin\n"))
7952 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
7953 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
7954 preventing them from being garbage-collected during its lifetime.
7957 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
7958 Return an object representing store file @var{name} containing
7959 @var{text}. @var{text} is a sequence of strings and file-like objects,
7963 (mixed-text-file "profile"
7964 "export PATH=" coreutils "/bin:" grep "/bin")
7967 This is the declarative counterpart of @code{text-file*}.
7970 @deffn {Scheme Procedure} file-union @var{name} @var{files}
7971 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
7972 Each item in @var{files} must be a two-element list where the first element is the
7973 file name to use in the new directory, and the second element is a gexp
7974 denoting the target file. Here's an example:
7978 `(("hosts" ,(plain-file "hosts"
7979 "127.0.0.1 localhost"))
7980 ("bashrc" ,(plain-file "bashrc"
7981 "alias ls='ls --color=auto'"))))
7984 This yields an @code{etc} directory containing these two files.
7987 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
7988 Return a directory that is the union of @var{things}, where @var{things} is a list of
7989 file-like objects denoting directories. For example:
7992 (directory-union "guile+emacs" (list guile emacs))
7995 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
7998 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
7999 Return a file-like object that expands to the concatenation of @var{obj}
8000 and @var{suffix}, where @var{obj} is a lowerable object and each
8001 @var{suffix} is a string.
8003 As an example, consider this gexp:
8006 (gexp->script "run-uname"
8007 #~(system* #$(file-append coreutils
8011 The same effect could be achieved with:
8014 (gexp->script "run-uname"
8015 #~(system* (string-append #$coreutils
8019 There is one difference though: in the @code{file-append} case, the
8020 resulting script contains the absolute file name as a string, whereas in
8021 the second case, the resulting script contains a @code{(string-append
8022 @dots{})} expression to construct the file name @emph{at run time}.
8026 Of course, in addition to gexps embedded in ``host'' code, there are
8027 also modules containing build tools. To make it clear that they are
8028 meant to be used in the build stratum, these modules are kept in the
8029 @code{(guix build @dots{})} name space.
8031 @cindex lowering, of high-level objects in gexps
8032 Internally, high-level objects are @dfn{lowered}, using their compiler,
8033 to either derivations or store items. For instance, lowering a package
8034 yields a derivation, and lowering a @code{plain-file} yields a store
8035 item. This is achieved using the @code{lower-object} monadic procedure.
8037 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
8039 Return as a value in @var{%store-monad} the derivation or store item
8040 corresponding to @var{obj} for @var{system}, cross-compiling for
8041 @var{target} if @var{target} is true. @var{obj} must be an object that
8042 has an associated gexp compiler, such as a @code{<package>}.
8045 @node Invoking guix repl
8046 @section Invoking @command{guix repl}
8048 @cindex REPL, read-eval-print loop
8049 The @command{guix repl} command spawns a Guile @dfn{read-eval-print loop}
8050 (REPL) for interactive programming (@pxref{Using Guile Interactively,,, guile,
8051 GNU Guile Reference Manual}). Compared to just launching the @command{guile}
8052 command, @command{guix repl} guarantees that all the Guix modules and all its
8053 dependencies are available in the search path. You can use it this way:
8057 scheme@@(guile-user)> ,use (gnu packages base)
8058 scheme@@(guile-user)> coreutils
8059 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
8063 In addition, @command{guix repl} implements a simple machine-readable REPL
8064 protocol for use by @code{(guix inferior)}, a facility to interact with
8065 @dfn{inferiors}, separate processes running a potentially different revision
8068 The available options are as follows:
8071 @item --type=@var{type}
8072 @itemx -t @var{type}
8073 Start a REPL of the given @var{TYPE}, which can be one of the following:
8077 This is default, and it spawns a standard full-featured Guile REPL.
8079 Spawn a REPL that uses the machine-readable protocol. This is the protocol
8080 that the @code{(guix inferior)} module speaks.
8083 @item --listen=@var{endpoint}
8084 By default, @command{guix repl} reads from standard input and writes to
8085 standard output. When this option is passed, it will instead listen for
8086 connections on @var{endpoint}. Here are examples of valid options:
8089 @item --listen=tcp:37146
8090 Accept connections on localhost on port 37146.
8092 @item --listen=unix:/tmp/socket
8093 Accept connections on the Unix-domain socket @file{/tmp/socket}.
8096 @item --load-path=@var{directory}
8097 @itemx -L @var{directory}
8098 Add @var{directory} to the front of the package module search path
8099 (@pxref{Package Modules}).
8101 This allows users to define their own packages and make them visible to
8102 the command-line tool.
8105 Inhibit loading of the @file{~/.guile} file. By default, that
8106 configuration file is loaded when spawning a @code{guile} REPL.
8109 @c *********************************************************************
8113 This section describes Guix command-line utilities. Some of them are
8114 primarily targeted at developers and users who write new package
8115 definitions, while others are more generally useful. They complement
8116 the Scheme programming interface of Guix in a convenient way.
8119 * Invoking guix build:: Building packages from the command line.
8120 * Invoking guix edit:: Editing package definitions.
8121 * Invoking guix download:: Downloading a file and printing its hash.
8122 * Invoking guix hash:: Computing the cryptographic hash of a file.
8123 * Invoking guix import:: Importing package definitions.
8124 * Invoking guix refresh:: Updating package definitions.
8125 * Invoking guix lint:: Finding errors in package definitions.
8126 * Invoking guix size:: Profiling disk usage.
8127 * Invoking guix graph:: Visualizing the graph of packages.
8128 * Invoking guix publish:: Sharing substitutes.
8129 * Invoking guix challenge:: Challenging substitute servers.
8130 * Invoking guix copy:: Copying to and from a remote store.
8131 * Invoking guix container:: Process isolation.
8132 * Invoking guix weather:: Assessing substitute availability.
8133 * Invoking guix processes:: Listing client processes.
8136 @node Invoking guix build
8137 @section Invoking @command{guix build}
8139 @cindex package building
8140 @cindex @command{guix build}
8141 The @command{guix build} command builds packages or derivations and
8142 their dependencies, and prints the resulting store paths. Note that it
8143 does not modify the user's profile---this is the job of the
8144 @command{guix package} command (@pxref{Invoking guix package}). Thus,
8145 it is mainly useful for distribution developers.
8147 The general syntax is:
8150 guix build @var{options} @var{package-or-derivation}@dots{}
8153 As an example, the following command builds the latest versions of Emacs
8154 and of Guile, displays their build logs, and finally displays the
8155 resulting directories:
8158 guix build emacs guile
8161 Similarly, the following command builds all the available packages:
8164 guix build --quiet --keep-going \
8165 `guix package -A | cut -f1,2 --output-delimiter=@@`
8168 @var{package-or-derivation} may be either the name of a package found in
8169 the software distribution such as @code{coreutils} or
8170 @code{coreutils@@8.20}, or a derivation such as
8171 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
8172 package with the corresponding name (and optionally version) is searched
8173 for among the GNU distribution modules (@pxref{Package Modules}).
8175 Alternatively, the @code{--expression} option may be used to specify a
8176 Scheme expression that evaluates to a package; this is useful when
8177 disambiguating among several same-named packages or package variants is
8180 There may be zero or more @var{options}. The available options are
8181 described in the subsections below.
8184 * Common Build Options:: Build options for most commands.
8185 * Package Transformation Options:: Creating variants of packages.
8186 * Additional Build Options:: Options specific to 'guix build'.
8187 * Debugging Build Failures:: Real life packaging experience.
8190 @node Common Build Options
8191 @subsection Common Build Options
8193 A number of options that control the build process are common to
8194 @command{guix build} and other commands that can spawn builds, such as
8195 @command{guix package} or @command{guix archive}. These are the
8200 @item --load-path=@var{directory}
8201 @itemx -L @var{directory}
8202 Add @var{directory} to the front of the package module search path
8203 (@pxref{Package Modules}).
8205 This allows users to define their own packages and make them visible to
8206 the command-line tools.
8210 Keep the build tree of failed builds. Thus, if a build fails, its build
8211 tree is kept under @file{/tmp}, in a directory whose name is shown at
8212 the end of the build log. This is useful when debugging build issues.
8213 @xref{Debugging Build Failures}, for tips and tricks on how to debug
8216 This option implies @option{--no-offload}, and it has no effect when
8217 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
8218 Store, the @code{GUIX_DAEMON_SOCKET} variable}).
8222 Keep going when some of the derivations fail to build; return only once
8223 all the builds have either completed or failed.
8225 The default behavior is to stop as soon as one of the specified
8226 derivations has failed.
8230 Do not build the derivations.
8232 @anchor{fallback-option}
8234 When substituting a pre-built binary fails, fall back to building
8235 packages locally (@pxref{Substitution Failure}).
8237 @item --substitute-urls=@var{urls}
8238 @anchor{client-substitute-urls}
8239 Consider @var{urls} the whitespace-separated list of substitute source
8240 URLs, overriding the default list of URLs of @command{guix-daemon}
8241 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
8243 This means that substitutes may be downloaded from @var{urls}, provided
8244 they are signed by a key authorized by the system administrator
8245 (@pxref{Substitutes}).
8247 When @var{urls} is the empty string, substitutes are effectively
8250 @item --no-substitutes
8251 Do not use substitutes for build products. That is, always build things
8252 locally instead of allowing downloads of pre-built binaries
8253 (@pxref{Substitutes}).
8256 Do not ``graft'' packages. In practice, this means that package updates
8257 available as grafts are not applied. @xref{Security Updates}, for more
8258 information on grafts.
8260 @item --rounds=@var{n}
8261 Build each derivation @var{n} times in a row, and raise an error if
8262 consecutive build results are not bit-for-bit identical.
8264 This is a useful way to detect non-deterministic builds processes.
8265 Non-deterministic build processes are a problem because they make it
8266 practically impossible for users to @emph{verify} whether third-party
8267 binaries are genuine. @xref{Invoking guix challenge}, for more.
8269 Note that, currently, the differing build results are not kept around,
8270 so you will have to manually investigate in case of an error---e.g., by
8271 stashing one of the build results with @code{guix archive --export}
8272 (@pxref{Invoking guix archive}), then rebuilding, and finally comparing
8276 Do not use offload builds to other machines (@pxref{Daemon Offload
8277 Setup}). That is, always build things locally instead of offloading
8278 builds to remote machines.
8280 @item --max-silent-time=@var{seconds}
8281 When the build or substitution process remains silent for more than
8282 @var{seconds}, terminate it and report a build failure.
8284 By default, the daemon's setting is honored (@pxref{Invoking
8285 guix-daemon, @code{--max-silent-time}}).
8287 @item --timeout=@var{seconds}
8288 Likewise, when the build or substitution process lasts for more than
8289 @var{seconds}, terminate it and report a build failure.
8291 By default, the daemon's setting is honored (@pxref{Invoking
8292 guix-daemon, @code{--timeout}}).
8294 @c Note: This option is actually not part of %standard-build-options but
8295 @c most programs honor it.
8296 @cindex verbosity, of the command-line tools
8297 @cindex build logs, verbosity
8298 @item -v @var{level}
8299 @itemx --verbosity=@var{level}
8300 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
8301 output is produced, 1 is for quiet output, and 2 shows all the build log
8302 output on standard error.
8304 @item --cores=@var{n}
8306 Allow the use of up to @var{n} CPU cores for the build. The special
8307 value @code{0} means to use as many CPU cores as available.
8309 @item --max-jobs=@var{n}
8311 Allow at most @var{n} build jobs in parallel. @xref{Invoking
8312 guix-daemon, @code{--max-jobs}}, for details about this option and the
8313 equivalent @command{guix-daemon} option.
8315 @item --debug=@var{level}
8316 Produce debugging output coming from the build daemon. @var{level} must be an
8317 integer between 0 and 5; higher means more verbose output. Setting a level of
8318 4 or more may be helpful when debugging setup issues with the build daemon.
8322 Behind the scenes, @command{guix build} is essentially an interface to
8323 the @code{package-derivation} procedure of the @code{(guix packages)}
8324 module, and to the @code{build-derivations} procedure of the @code{(guix
8325 derivations)} module.
8327 In addition to options explicitly passed on the command line,
8328 @command{guix build} and other @command{guix} commands that support
8329 building honor the @code{GUIX_BUILD_OPTIONS} environment variable.
8331 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
8332 Users can define this variable to a list of command line options that
8333 will automatically be used by @command{guix build} and other
8334 @command{guix} commands that can perform builds, as in the example
8338 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
8341 These options are parsed independently, and the result is appended to
8342 the parsed command-line options.
8346 @node Package Transformation Options
8347 @subsection Package Transformation Options
8349 @cindex package variants
8350 Another set of command-line options supported by @command{guix build}
8351 and also @command{guix package} are @dfn{package transformation
8352 options}. These are options that make it possible to define @dfn{package
8353 variants}---for instance, packages built from different source code.
8354 This is a convenient way to create customized packages on the fly
8355 without having to type in the definitions of package variants
8356 (@pxref{Defining Packages}).
8360 @item --with-source=@var{source}
8361 @itemx --with-source=@var{package}=@var{source}
8362 @itemx --with-source=@var{package}@@@var{version}=@var{source}
8363 Use @var{source} as the source of @var{package}, and @var{version} as
8365 @var{source} must be a file name or a URL, as for @command{guix
8366 download} (@pxref{Invoking guix download}).
8368 When @var{package} is omitted,
8369 it is taken to be the package name specified on the
8370 command line that matches the base of @var{source}---e.g.,
8371 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
8372 package is @code{guile}.
8374 Likewise, when @var{version} is omitted, the version string is inferred from
8375 @var{source}; in the previous example, it is @code{2.0.10}.
8377 This option allows users to try out versions of packages other than the
8378 one provided by the distribution. The example below downloads
8379 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
8380 the @code{ed} package:
8383 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
8386 As a developer, @code{--with-source} makes it easy to test release
8390 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
8393 @dots{} or to build from a checkout in a pristine environment:
8396 $ git clone git://git.sv.gnu.org/guix.git
8397 $ guix build guix --with-source=guix@@1.0=./guix
8400 @item --with-input=@var{package}=@var{replacement}
8401 Replace dependency on @var{package} by a dependency on
8402 @var{replacement}. @var{package} must be a package name, and
8403 @var{replacement} must be a package specification such as @code{guile}
8404 or @code{guile@@1.8}.
8406 For instance, the following command builds Guix, but replaces its
8407 dependency on the current stable version of Guile with a dependency on
8408 the legacy version of Guile, @code{guile@@2.0}:
8411 guix build --with-input=guile=guile@@2.0 guix
8414 This is a recursive, deep replacement. So in this example, both
8415 @code{guix} and its dependency @code{guile-json} (which also depends on
8416 @code{guile}) get rebuilt against @code{guile@@2.0}.
8418 This is implemented using the @code{package-input-rewriting} Scheme
8419 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
8421 @item --with-graft=@var{package}=@var{replacement}
8422 This is similar to @code{--with-input} but with an important difference:
8423 instead of rebuilding the whole dependency chain, @var{replacement} is
8424 built and then @dfn{grafted} onto the binaries that were initially
8425 referring to @var{package}. @xref{Security Updates}, for more
8426 information on grafts.
8428 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
8429 and all its dependencies, replacing references to the version of GnuTLS
8430 they currently refer to:
8433 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
8436 This has the advantage of being much faster than rebuilding everything.
8437 But there is a caveat: it works if and only if @var{package} and
8438 @var{replacement} are strictly compatible---for example, if they provide
8439 a library, the application binary interface (ABI) of those libraries
8440 must be compatible. If @var{replacement} is somehow incompatible with
8441 @var{package}, then the resulting package may be unusable. Use with
8444 @item --with-git-url=@var{package}=@var{url}
8445 @cindex Git, using the latest commit
8446 @cindex latest commit, building
8447 Build @var{package} from the latest commit of the @code{master} branch of the
8448 Git repository at @var{url}. Git sub-modules of the repository are fetched,
8451 For example, the following command builds the NumPy Python library against the
8452 latest commit of the master branch of Python itself:
8455 guix build python-numpy \
8456 --with-git-url=python=https://github.com/python/cpython
8459 This option can also be combined with @code{--with-branch} or
8460 @code{--with-commit} (see below).
8462 @cindex continuous integration
8463 Obviously, since it uses the latest commit of the given branch, the result of
8464 such a command varies over time. Nevertheless it is a convenient way to
8465 rebuild entire software stacks against the latest commit of one or more
8466 packages. This is particularly useful in the context of continuous
8469 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
8470 consecutive accesses to the same repository. You may want to clean it up once
8471 in a while to save disk space.
8473 @item --with-branch=@var{package}=@var{branch}
8474 Build @var{package} from the latest commit of @var{branch}. If the
8475 @code{source} field of @var{package} is an origin with the @code{git-fetch}
8476 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
8477 repository URL is taken from that @code{source}. Otherwise you have to use
8478 @code{--with-git-url} to specify the URL of the Git repository.
8480 For instance, the following command builds @code{guile-sqlite3} from the
8481 latest commit of its @code{master} branch, and then builds @code{guix} (which
8482 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
8483 specific @code{guile-sqlite3} build:
8486 guix build --with-branch=guile-sqlite3=master cuirass
8489 @item --with-commit=@var{package}=@var{commit}
8490 This is similar to @code{--with-branch}, except that it builds from
8491 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
8492 Git commit SHA1 identifier or a tag.
8495 @node Additional Build Options
8496 @subsection Additional Build Options
8498 The command-line options presented below are specific to @command{guix
8505 Build quietly, without displaying the build log; this is equivalent to
8506 @code{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
8507 (or similar) and can always be retrieved using the @option{--log-file} option.
8509 @item --file=@var{file}
8510 @itemx -f @var{file}
8511 Build the package, derivation, or other file-like object that the code within
8512 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
8514 As an example, @var{file} might contain a package definition like this
8515 (@pxref{Defining Packages}):
8518 @include package-hello.scm
8521 @item --manifest=@var{manifest}
8522 @itemx -m @var{manifest}
8523 Build all packages listed in the given @var{manifest}
8524 (@pxref{profile-manifest, @option{--manifest}}).
8526 @item --expression=@var{expr}
8527 @itemx -e @var{expr}
8528 Build the package or derivation @var{expr} evaluates to.
8530 For example, @var{expr} may be @code{(@@ (gnu packages guile)
8531 guile-1.8)}, which unambiguously designates this specific variant of
8532 version 1.8 of Guile.
8534 Alternatively, @var{expr} may be a G-expression, in which case it is used
8535 as a build program passed to @code{gexp->derivation}
8536 (@pxref{G-Expressions}).
8538 Lastly, @var{expr} may refer to a zero-argument monadic procedure
8539 (@pxref{The Store Monad}). The procedure must return a derivation as a
8540 monadic value, which is then passed through @code{run-with-store}.
8544 Build the source derivations of the packages, rather than the packages
8547 For instance, @code{guix build -S gcc} returns something like
8548 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
8551 The returned source tarball is the result of applying any patches and
8552 code snippets specified in the package @code{origin} (@pxref{Defining
8555 Note that @command{guix build -S} compiles the sources only of the
8556 specified packages. They do not include the sources of statically
8557 linked dependencies and by themselves are insufficient for reproducing
8561 Fetch and return the source of @var{package-or-derivation} and all their
8562 dependencies, recursively. This is a handy way to obtain a local copy
8563 of all the source code needed to build @var{packages}, allowing you to
8564 eventually build them even without network access. It is an extension
8565 of the @code{--source} option and can accept one of the following
8566 optional argument values:
8570 This value causes the @code{--sources} option to behave in the same way
8571 as the @code{--source} option.
8574 Build the source derivations of all packages, including any source that
8575 might be listed as @code{inputs}. This is the default value.
8578 $ guix build --sources tzdata
8579 The following derivations will be built:
8580 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
8581 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8585 Build the source derivations of all packages, as well of all transitive
8586 inputs to the packages. This can be used e.g.@: to
8587 prefetch package source for later offline building.
8590 $ guix build --sources=transitive tzdata
8591 The following derivations will be built:
8592 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
8593 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
8594 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
8595 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
8596 /gnu/store/@dots{}-make-4.1.tar.xz.drv
8597 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
8603 @item --system=@var{system}
8604 @itemx -s @var{system}
8605 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
8606 the system type of the build host. The @command{guix build} command allows
8607 you to repeat this option several times, in which case it builds for all the
8608 specified systems; other commands ignore extraneous @option{-s} options.
8611 The @code{--system} flag is for @emph{native} compilation and must not
8612 be confused with cross-compilation. See @code{--target} below for
8613 information on cross-compilation.
8616 An example use of this is on Linux-based systems, which can emulate
8617 different personalities. For instance, passing
8618 @code{--system=i686-linux} on an @code{x86_64-linux} system or
8619 @code{--system=armhf-linux} on an @code{aarch64-linux} system allows you
8620 to build packages in a complete 32-bit environment.
8623 Building for an @code{armhf-linux} system is unconditionally enabled on
8624 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
8625 allow for this functionality, notably the ThunderX.
8628 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
8629 is enabled (@pxref{Virtualization Services,
8630 @code{qemu-binfmt-service-type}}), you can build for any system for
8631 which a QEMU @code{binfmt_misc} handler is installed.
8633 Builds for a system other than that of the machine you are using can
8634 also be offloaded to a remote machine of the right architecture.
8635 @xref{Daemon Offload Setup}, for more information on offloading.
8637 @item --target=@var{triplet}
8638 @cindex cross-compilation
8639 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
8640 as @code{"mips64el-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
8641 configuration triplets,, autoconf, Autoconf}).
8643 @anchor{build-check}
8645 @cindex determinism, checking
8646 @cindex reproducibility, checking
8647 Rebuild @var{package-or-derivation}, which are already available in the
8648 store, and raise an error if the build results are not bit-for-bit
8651 This mechanism allows you to check whether previously installed
8652 substitutes are genuine (@pxref{Substitutes}), or whether the build result
8653 of a package is deterministic. @xref{Invoking guix challenge}, for more
8654 background information and tools.
8656 When used in conjunction with @option{--keep-failed}, the differing
8657 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
8658 This makes it easy to look for differences between the two results.
8661 @cindex repairing store items
8662 @cindex corruption, recovering from
8663 Attempt to repair the specified store items, if they are corrupt, by
8664 re-downloading or rebuilding them.
8666 This operation is not atomic and thus restricted to @code{root}.
8670 Return the derivation paths, not the output paths, of the given
8673 @item --root=@var{file}
8674 @itemx -r @var{file}
8675 @cindex GC roots, adding
8676 @cindex garbage collector roots, adding
8677 Make @var{file} a symlink to the result, and register it as a garbage
8680 Consequently, the results of this @command{guix build} invocation are
8681 protected from garbage collection until @var{file} is removed. When
8682 that option is omitted, build results are eligible for garbage
8683 collection as soon as the build completes. @xref{Invoking guix gc}, for
8687 @cindex build logs, access
8688 Return the build log file names or URLs for the given
8689 @var{package-or-derivation}, or raise an error if build logs are
8692 This works regardless of how packages or derivations are specified. For
8693 instance, the following invocations are equivalent:
8696 guix build --log-file `guix build -d guile`
8697 guix build --log-file `guix build guile`
8698 guix build --log-file guile
8699 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
8702 If a log is unavailable locally, and unless @code{--no-substitutes} is
8703 passed, the command looks for a corresponding log on one of the
8704 substitute servers (as specified with @code{--substitute-urls}.)
8706 So for instance, imagine you want to see the build log of GDB on MIPS,
8707 but you are actually on an @code{x86_64} machine:
8710 $ guix build --log-file gdb -s mips64el-linux
8711 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
8714 You can freely access a huge library of build logs!
8717 @node Debugging Build Failures
8718 @subsection Debugging Build Failures
8720 @cindex build failures, debugging
8721 When defining a new package (@pxref{Defining Packages}), you will
8722 probably find yourself spending some time debugging and tweaking the
8723 build until it succeeds. To do that, you need to operate the build
8724 commands yourself in an environment as close as possible to the one the
8727 To that end, the first thing to do is to use the @option{--keep-failed}
8728 or @option{-K} option of @command{guix build}, which will keep the
8729 failed build tree in @file{/tmp} or whatever directory you specified as
8730 @code{TMPDIR} (@pxref{Invoking guix build, @code{--keep-failed}}).
8732 From there on, you can @command{cd} to the failed build tree and source
8733 the @file{environment-variables} file, which contains all the
8734 environment variable definitions that were in place when the build
8735 failed. So let's say you're debugging a build failure in package
8736 @code{foo}; a typical session would look like this:
8740 @dots{} @i{build fails}
8741 $ cd /tmp/guix-build-foo.drv-0
8742 $ source ./environment-variables
8746 Now, you can invoke commands as if you were the daemon (almost) and
8747 troubleshoot your build process.
8749 Sometimes it happens that, for example, a package's tests pass when you
8750 run them manually but they fail when the daemon runs them. This can
8751 happen because the daemon runs builds in containers where, unlike in our
8752 environment above, network access is missing, @file{/bin/sh} does not
8753 exist, etc. (@pxref{Build Environment Setup}).
8755 In such cases, you may need to run inspect the build process from within
8756 a container similar to the one the build daemon creates:
8761 $ cd /tmp/guix-build-foo.drv-0
8762 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
8763 [env]# source ./environment-variables
8767 Here, @command{guix environment -C} creates a container and spawns a new
8768 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
8769 strace gdb} part adds the @command{strace} and @command{gdb} commands to
8770 the container, which would may find handy while debugging. The
8771 @option{--no-grafts} option makes sure we get the exact same
8772 environment, with ungrafted packages (@pxref{Security Updates}, for more
8775 To get closer to a container like that used by the build daemon, we can
8776 remove @file{/bin/sh}:
8782 (Don't worry, this is harmless: this is all happening in the throw-away
8783 container created by @command{guix environment}.)
8785 The @command{strace} command is probably not in the search path, but we
8789 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
8792 In this way, not only you will have reproduced the environment variables
8793 the daemon uses, you will also be running the build process in a container
8794 similar to the one the daemon uses.
8797 @node Invoking guix edit
8798 @section Invoking @command{guix edit}
8800 @cindex @command{guix edit}
8801 @cindex package definition, editing
8802 So many packages, so many source files! The @command{guix edit} command
8803 facilitates the life of users and packagers by pointing their editor at
8804 the source file containing the definition of the specified packages.
8808 guix edit gcc@@4.9 vim
8812 launches the program specified in the @code{VISUAL} or in the
8813 @code{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
8816 If you are using a Guix Git checkout (@pxref{Building from Git}), or
8817 have created your own packages on @code{GUIX_PACKAGE_PATH}
8818 (@pxref{Package Modules}), you will be able to edit the package
8819 recipes. In other cases, you will be able to examine the read-only recipes
8820 for packages currently in the store.
8822 Instead of @code{GUIX_PACKAGE_PATH}, the command-line option
8823 @code{--load-path=@var{directory}} (or in short @code{-L
8824 @var{directory}}) allows you to add @var{directory} to the front of the
8825 package module search path and so make your own packages visible.
8827 @node Invoking guix download
8828 @section Invoking @command{guix download}
8830 @cindex @command{guix download}
8831 @cindex downloading package sources
8832 When writing a package definition, developers typically need to download
8833 a source tarball, compute its SHA256 hash, and write that
8834 hash in the package definition (@pxref{Defining Packages}). The
8835 @command{guix download} tool helps with this task: it downloads a file
8836 from the given URI, adds it to the store, and prints both its file name
8837 in the store and its SHA256 hash.
8839 The fact that the downloaded file is added to the store saves bandwidth:
8840 when the developer eventually tries to build the newly defined package
8841 with @command{guix build}, the source tarball will not have to be
8842 downloaded again because it is already in the store. It is also a
8843 convenient way to temporarily stash files, which may be deleted
8844 eventually (@pxref{Invoking guix gc}).
8846 The @command{guix download} command supports the same URIs as used in
8847 package definitions. In particular, it supports @code{mirror://} URIs.
8848 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
8849 Guile bindings for GnuTLS are available in the user's environment; when
8850 they are not available, an error is raised. @xref{Guile Preparations,
8851 how to install the GnuTLS bindings for Guile,, gnutls-guile,
8852 GnuTLS-Guile}, for more information.
8854 @command{guix download} verifies HTTPS server certificates by loading
8855 the certificates of X.509 authorities from the directory pointed to by
8856 the @code{SSL_CERT_DIR} environment variable (@pxref{X.509
8857 Certificates}), unless @option{--no-check-certificate} is used.
8859 The following options are available:
8862 @item --format=@var{fmt}
8864 Write the hash in the format specified by @var{fmt}. For more
8865 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
8867 @item --no-check-certificate
8868 Do not validate the X.509 certificates of HTTPS servers.
8870 When using this option, you have @emph{absolutely no guarantee} that you
8871 are communicating with the authentic server responsible for the given
8872 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
8874 @item --output=@var{file}
8875 @itemx -o @var{file}
8876 Save the downloaded file to @var{file} instead of adding it to the
8880 @node Invoking guix hash
8881 @section Invoking @command{guix hash}
8883 @cindex @command{guix hash}
8884 The @command{guix hash} command computes the SHA256 hash of a file.
8885 It is primarily a convenience tool for anyone contributing to the
8886 distribution: it computes the cryptographic hash of a file, which can be
8887 used in the definition of a package (@pxref{Defining Packages}).
8889 The general syntax is:
8892 guix hash @var{option} @var{file}
8895 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
8896 hash of data read from standard input. @command{guix hash} has the
8901 @item --format=@var{fmt}
8903 Write the hash in the format specified by @var{fmt}.
8905 Supported formats: @code{nix-base32}, @code{base32}, @code{base16}
8906 (@code{hex} and @code{hexadecimal} can be used as well).
8908 If the @option{--format} option is not specified, @command{guix hash}
8909 will output the hash in @code{nix-base32}. This representation is used
8910 in the definitions of packages.
8914 Compute the hash on @var{file} recursively.
8916 In this case, the hash is computed on an archive containing @var{file},
8917 including its children if it is a directory. Some of the metadata of
8918 @var{file} is part of the archive; for instance, when @var{file} is a
8919 regular file, the hash is different depending on whether @var{file} is
8920 executable or not. Metadata such as time stamps has no impact on the
8921 hash (@pxref{Invoking guix archive}).
8922 @c FIXME: Replace xref above with xref to an ``Archive'' section when
8927 When combined with @option{--recursive}, exclude version control system
8928 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.)
8931 As an example, here is how you would compute the hash of a Git checkout,
8932 which is useful when using the @code{git-fetch} method (@pxref{origin
8936 $ git clone http://example.org/foo.git
8942 @node Invoking guix import
8943 @section Invoking @command{guix import}
8945 @cindex importing packages
8946 @cindex package import
8947 @cindex package conversion
8948 @cindex Invoking @command{guix import}
8949 The @command{guix import} command is useful for people who would like to
8950 add a package to the distribution with as little work as
8951 possible---a legitimate demand. The command knows of a few
8952 repositories from which it can ``import'' package metadata. The result
8953 is a package definition, or a template thereof, in the format we know
8954 (@pxref{Defining Packages}).
8956 The general syntax is:
8959 guix import @var{importer} @var{options}@dots{}
8962 @var{importer} specifies the source from which to import package
8963 metadata, and @var{options} specifies a package identifier and other
8964 options specific to @var{importer}.
8966 Some of the importers rely on the ability to run the @command{gpgv} command.
8967 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
8970 Currently, the available ``importers'' are:
8974 Import metadata for the given GNU package. This provides a template
8975 for the latest version of that GNU package, including the hash of its
8976 source tarball, and its canonical synopsis and description.
8978 Additional information such as the package dependencies and its
8979 license needs to be figured out manually.
8981 For example, the following command returns a package definition for
8985 guix import gnu hello
8988 Specific command-line options are:
8991 @item --key-download=@var{policy}
8992 As for @code{guix refresh}, specify the policy to handle missing OpenPGP
8993 keys when verifying the package signature. @xref{Invoking guix
8994 refresh, @code{--key-download}}.
8999 Import metadata from the @uref{https://pypi.python.org/, Python Package
9000 Index}. Information is taken from the JSON-formatted description
9001 available at @code{pypi.python.org} and usually includes all the relevant
9002 information, including package dependencies. For maximum efficiency, it
9003 is recommended to install the @command{unzip} utility, so that the
9004 importer can unzip Python wheels and gather data from them.
9006 The command below imports metadata for the @code{itsdangerous} Python
9010 guix import pypi itsdangerous
9016 Traverse the dependency graph of the given upstream package recursively
9017 and generate package expressions for all those packages that are not yet
9023 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
9024 is taken from the JSON-formatted description available at
9025 @code{rubygems.org} and includes most relevant information, including
9026 runtime dependencies. There are some caveats, however. The metadata
9027 doesn't distinguish between synopses and descriptions, so the same string
9028 is used for both fields. Additionally, the details of non-Ruby
9029 dependencies required to build native extensions is unavailable and left
9030 as an exercise to the packager.
9032 The command below imports metadata for the @code{rails} Ruby package:
9035 guix import gem rails
9041 Traverse the dependency graph of the given upstream package recursively
9042 and generate package expressions for all those packages that are not yet
9048 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
9049 Information is taken from the JSON-formatted metadata provided through
9050 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
9051 relevant information, such as module dependencies. License information
9052 should be checked closely. If Perl is available in the store, then the
9053 @code{corelist} utility will be used to filter core modules out of the
9054 list of dependencies.
9056 The command command below imports metadata for the @code{Acme::Boolean}
9060 guix import cpan Acme::Boolean
9065 @cindex Bioconductor
9066 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
9067 central repository for the @uref{https://r-project.org, GNU@tie{}R
9068 statistical and graphical environment}.
9070 Information is extracted from the @code{DESCRIPTION} file of the package.
9072 The command command below imports metadata for the @code{Cairo}
9076 guix import cran Cairo
9079 When @code{--recursive} is added, the importer will traverse the
9080 dependency graph of the given upstream package recursively and generate
9081 package expressions for all those packages that are not yet in Guix.
9083 When @code{--archive=bioconductor} is added, metadata is imported from
9084 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
9085 packages for for the analysis and comprehension of high-throughput
9086 genomic data in bioinformatics.
9088 Information is extracted from the @code{DESCRIPTION} file contained in the
9091 The command below imports metadata for the @code{GenomicRanges}
9095 guix import cran --archive=bioconductor GenomicRanges
9098 Finally, you can also import R packages that have not yet been published on
9099 CRAN or Bioconductor as long as they are in a git repository. Use
9100 @code{--archive=git} followed by the URL of the git repository:
9103 guix import cran --archive=git https://github.com/immunogenomics/harmony
9109 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
9110 comprehensive TeX archive network for TeX packages that are part of the
9111 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
9113 Information about the package is obtained through the XML API provided
9114 by CTAN, while the source code is downloaded from the SVN repository of
9115 the Tex Live project. This is done because the CTAN does not keep
9118 The command command below imports metadata for the @code{fontspec}
9122 guix import texlive fontspec
9125 When @code{--archive=DIRECTORY} is added, the source code is downloaded
9126 not from the @file{latex} sub-directory of the @file{texmf-dist/source}
9127 tree in the TeX Live SVN repository, but from the specified sibling
9128 directory under the same root.
9130 The command below imports metadata for the @code{ifxetex} package from
9131 CTAN while fetching the sources from the directory
9132 @file{texmf/source/generic}:
9135 guix import texlive --archive=generic ifxetex
9139 @cindex JSON, import
9140 Import package metadata from a local JSON file. Consider the following
9141 example package definition in JSON format:
9147 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
9148 "build-system": "gnu",
9149 "home-page": "https://www.gnu.org/software/hello/",
9150 "synopsis": "Hello, GNU world: An example GNU package",
9151 "description": "GNU Hello prints a greeting.",
9152 "license": "GPL-3.0+",
9153 "native-inputs": ["gettext"]
9157 The field names are the same as for the @code{<package>} record
9158 (@xref{Defining Packages}). References to other packages are provided
9159 as JSON lists of quoted package specification strings such as
9160 @code{guile} or @code{guile@@2.0}.
9162 The importer also supports a more explicit source definition using the
9163 common fields for @code{<origin>} records:
9169 "method": "url-fetch",
9170 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
9172 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
9179 The command below reads metadata from the JSON file @code{hello.json}
9180 and outputs a package expression:
9183 guix import json hello.json
9187 Import metadata from a local copy of the source of the
9188 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
9189 relies on the @command{nix-instantiate} command of
9190 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
9191 typically written in a mixture of Nix-language and Bash code. This
9192 command only imports the high-level package structure that is written in
9193 the Nix language. It normally includes all the basic fields of a
9196 When importing a GNU package, the synopsis and descriptions are replaced
9197 by their canonical upstream variant.
9199 Usually, you will first need to do:
9202 export NIX_REMOTE=daemon
9206 so that @command{nix-instantiate} does not try to open the Nix database.
9208 As an example, the command below imports the package definition of
9209 LibreOffice (more precisely, it imports the definition of the package
9210 bound to the @code{libreoffice} top-level attribute):
9213 guix import nix ~/path/to/nixpkgs libreoffice
9218 Import metadata from the Haskell community's central package archive
9219 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
9220 Cabal files and includes all the relevant information, including package
9223 Specific command-line options are:
9228 Read a Cabal file from standard input.
9229 @item --no-test-dependencies
9231 Do not include dependencies required only by the test suites.
9232 @item --cabal-environment=@var{alist}
9233 @itemx -e @var{alist}
9234 @var{alist} is a Scheme alist defining the environment in which the
9235 Cabal conditionals are evaluated. The accepted keys are: @code{os},
9236 @code{arch}, @code{impl} and a string representing the name of a flag.
9237 The value associated with a flag has to be either the symbol
9238 @code{true} or @code{false}. The value associated with other keys
9239 has to conform to the Cabal file format definition. The default value
9240 associated with the keys @code{os}, @code{arch} and @code{impl} is
9241 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
9244 Traverse the dependency graph of the given upstream package recursively
9245 and generate package expressions for all those packages that are not yet
9249 The command below imports metadata for the latest version of the
9250 @code{HTTP} Haskell package without including test dependencies and
9251 specifying the value of the flag @samp{network-uri} as @code{false}:
9254 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
9257 A specific package version may optionally be specified by following the
9258 package name by an at-sign and a version number as in the following example:
9261 guix import hackage mtl@@2.1.3.1
9266 The @code{stackage} importer is a wrapper around the @code{hackage} one.
9267 It takes a package name, looks up the package version included in a
9268 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
9269 release and uses the @code{hackage} importer to retrieve its metadata.
9270 Note that it is up to you to select an LTS release compatible with the
9271 GHC compiler used by Guix.
9273 Specific command-line options are:
9276 @item --no-test-dependencies
9278 Do not include dependencies required only by the test suites.
9279 @item --lts-version=@var{version}
9280 @itemx -l @var{version}
9281 @var{version} is the desired LTS release version. If omitted the latest
9285 Traverse the dependency graph of the given upstream package recursively
9286 and generate package expressions for all those packages that are not yet
9290 The command below imports metadata for the @code{HTTP} Haskell package
9291 included in the LTS Stackage release version 7.18:
9294 guix import stackage --lts-version=7.18 HTTP
9299 Import metadata from an Emacs Lisp Package Archive (ELPA) package
9300 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9302 Specific command-line options are:
9305 @item --archive=@var{repo}
9306 @itemx -a @var{repo}
9307 @var{repo} identifies the archive repository from which to retrieve the
9308 information. Currently the supported repositories and their identifiers
9312 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
9313 identifier. This is the default.
9315 Packages from @code{elpa.gnu.org} are signed with one of the keys
9316 contained in the GnuPG keyring at
9317 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
9318 @code{emacs} package (@pxref{Package Installation, ELPA package
9319 signatures,, emacs, The GNU Emacs Manual}).
9322 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
9323 @code{melpa-stable} identifier.
9326 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
9332 Traverse the dependency graph of the given upstream package recursively
9333 and generate package expressions for all those packages that are not yet
9339 Import metadata from the crates.io Rust package repository
9340 @uref{https://crates.io, crates.io}, as in this example:
9343 guix import crate blake2-rfc
9346 The crate importer also allows you to specify a version string:
9349 guix import crate constant-time-eq@@0.1.0
9352 Additional options include:
9357 Traverse the dependency graph of the given upstream package recursively
9358 and generate package expressions for all those packages that are not yet
9365 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
9366 repository used by the OCaml community.
9369 The structure of the @command{guix import} code is modular. It would be
9370 useful to have more importers for other package formats, and your help
9371 is welcome here (@pxref{Contributing}).
9373 @node Invoking guix refresh
9374 @section Invoking @command{guix refresh}
9376 @cindex @command {guix refresh}
9377 The primary audience of the @command{guix refresh} command is developers
9378 of the GNU software distribution. By default, it reports any packages
9379 provided by the distribution that are outdated compared to the latest
9380 upstream version, like this:
9384 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
9385 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
9388 Alternately, one can specify packages to consider, in which case a
9389 warning is emitted for packages that lack an updater:
9392 $ guix refresh coreutils guile guile-ssh
9393 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
9394 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
9397 @command{guix refresh} browses the upstream repository of each package and determines
9398 the highest version number of the releases therein. The command
9399 knows how to update specific types of packages: GNU packages, ELPA
9400 packages, etc.---see the documentation for @option{--type} below. There
9401 are many packages, though, for which it lacks a method to determine
9402 whether a new upstream release is available. However, the mechanism is
9403 extensible, so feel free to get in touch with us to add a new method!
9408 Consider the packages specified, and all the packages upon which they depend.
9411 $ guix refresh --recursive coreutils
9412 gnu/packages/acl.scm:35:2: warning: no updater for acl
9413 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
9414 gnu/packages/xml.scm:68:2: warning: no updater for expat
9415 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
9421 Sometimes the upstream name differs from the package name used in Guix,
9422 and @command{guix refresh} needs a little help. Most updaters honor the
9423 @code{upstream-name} property in package definitions, which can be used
9427 (define-public network-manager
9429 (name "network-manager")
9431 (properties '((upstream-name . "NetworkManager")))))
9434 When passed @code{--update}, it modifies distribution source files to
9435 update the version numbers and source tarball hashes of those package
9436 recipes (@pxref{Defining Packages}). This is achieved by downloading
9437 each package's latest source tarball and its associated OpenPGP
9438 signature, authenticating the downloaded tarball against its signature
9439 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
9440 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
9443 key used to sign the tarball is missing from the user's keyring, an
9444 attempt is made to automatically retrieve it from a public key server;
9445 when this is successful, the key is added to the user's keyring; otherwise,
9446 @command{guix refresh} reports an error.
9448 The following options are supported:
9452 @item --expression=@var{expr}
9453 @itemx -e @var{expr}
9454 Consider the package @var{expr} evaluates to.
9456 This is useful to precisely refer to a package, as in this example:
9459 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
9462 This command lists the dependents of the ``final'' libc (essentially all
9467 Update distribution source files (package recipes) in place. This is
9468 usually run from a checkout of the Guix source tree (@pxref{Running
9469 Guix Before It Is Installed}):
9472 $ ./pre-inst-env guix refresh -s non-core -u
9475 @xref{Defining Packages}, for more information on package definitions.
9477 @item --select=[@var{subset}]
9478 @itemx -s @var{subset}
9479 Select all the packages in @var{subset}, one of @code{core} or
9482 The @code{core} subset refers to all the packages at the core of the
9483 distribution---i.e., packages that are used to build ``everything
9484 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
9485 changing one of these packages in the distribution entails a rebuild of
9486 all the others. Thus, such updates are an inconvenience to users in
9487 terms of build time or bandwidth used to achieve the upgrade.
9489 The @code{non-core} subset refers to the remaining packages. It is
9490 typically useful in cases where an update of the core packages would be
9493 @item --manifest=@var{file}
9494 @itemx -m @var{file}
9495 Select all the packages from the manifest in @var{file}. This is useful to
9496 check if any packages of the user manifest can be updated.
9498 @item --type=@var{updater}
9499 @itemx -t @var{updater}
9500 Select only packages handled by @var{updater} (may be a comma-separated
9501 list of updaters). Currently, @var{updater} may be one of:
9505 the updater for GNU packages;
9507 the updater for GNOME packages;
9509 the updater for KDE packages;
9511 the updater for X.org packages;
9513 the updater for packages hosted on kernel.org;
9515 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
9517 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
9519 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
9521 the updater for @uref{https://www.cpan.org/, CPAN} packages;
9523 the updater for @uref{https://pypi.python.org, PyPI} packages.
9525 the updater for @uref{https://rubygems.org, RubyGems} packages.
9527 the updater for @uref{https://github.com, GitHub} packages.
9529 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
9531 the updater for @uref{https://www.stackage.org, Stackage} packages.
9533 the updater for @uref{https://crates.io, Crates} packages.
9535 the updater for @uref{https://launchpad.net, Launchpad} packages.
9538 For instance, the following command only checks for updates of Emacs
9539 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
9542 $ guix refresh --type=elpa,cran
9543 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
9544 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
9549 In addition, @command{guix refresh} can be passed one or more package
9550 names, as in this example:
9553 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
9557 The command above specifically updates the @code{emacs} and
9558 @code{idutils} packages. The @code{--select} option would have no
9559 effect in this case.
9561 When considering whether to upgrade a package, it is sometimes
9562 convenient to know which packages would be affected by the upgrade and
9563 should be checked for compatibility. For this the following option may
9564 be used when passing @command{guix refresh} one or more package names:
9568 @item --list-updaters
9570 List available updaters and exit (see @option{--type} above.)
9572 For each updater, display the fraction of packages it covers; at the
9573 end, display the fraction of packages covered by all these updaters.
9575 @item --list-dependent
9577 List top-level dependent packages that would need to be rebuilt as a
9578 result of upgrading one or more packages.
9580 @xref{Invoking guix graph, the @code{reverse-package} type of
9581 @command{guix graph}}, for information on how to visualize the list of
9582 dependents of a package.
9586 Be aware that the @code{--list-dependent} option only
9587 @emph{approximates} the rebuilds that would be required as a result of
9588 an upgrade. More rebuilds might be required under some circumstances.
9591 $ guix refresh --list-dependent flex
9592 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
9593 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
9596 The command above lists a set of packages that could be built to check
9597 for compatibility with an upgraded @code{flex} package.
9601 @item --list-transitive
9602 List all the packages which one or more packages depend upon.
9605 $ guix refresh --list-transitive flex
9606 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
9607 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{}
9612 The command above lists a set of packages which, when changed, would cause
9613 @code{flex} to be rebuilt.
9615 The following options can be used to customize GnuPG operation:
9619 @item --gpg=@var{command}
9620 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
9621 for in @code{$PATH}.
9623 @item --keyring=@var{file}
9624 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
9625 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
9626 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
9627 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
9628 information on a tool to manipulate keybox files).
9630 When this option is omitted, @command{guix refresh} uses
9631 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
9632 signing keys. OpenPGP signatures are checked against keys from this keyring;
9633 missing keys are downloaded to this keyring as well (see
9634 @option{--key-download} below.)
9636 You can export keys from your default GPG keyring into a keybox file using
9637 commands like this one:
9640 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
9643 Likewise, you can fetch keys to a specific keybox file like this:
9646 gpg --no-default-keyring --keyring mykeyring.kbx \
9647 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
9650 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
9651 Privacy Guard}, for more information on GPG's @option{--keyring} option.
9653 @item --key-download=@var{policy}
9654 Handle missing OpenPGP keys according to @var{policy}, which may be one
9659 Always download missing OpenPGP keys from the key server, and add them
9660 to the user's GnuPG keyring.
9663 Never try to download missing OpenPGP keys. Instead just bail out.
9666 When a package signed with an unknown OpenPGP key is encountered, ask
9667 the user whether to download it or not. This is the default behavior.
9670 @item --key-server=@var{host}
9671 Use @var{host} as the OpenPGP key server when importing a public key.
9673 @item --load-path=@var{directory}
9674 Add @var{directory} to the front of the package module search path
9675 (@pxref{Package Modules}).
9677 This allows users to define their own packages and make them visible to
9678 the command-line tools.
9682 The @code{github} updater uses the
9683 @uref{https://developer.github.com/v3/, GitHub API} to query for new
9684 releases. When used repeatedly e.g.@: when refreshing all packages,
9685 GitHub will eventually refuse to answer any further API requests. By
9686 default 60 API requests per hour are allowed, and a full refresh on all
9687 GitHub packages in Guix requires more than this. Authentication with
9688 GitHub through the use of an API token alleviates these limits. To use
9689 an API token, set the environment variable @code{GUIX_GITHUB_TOKEN} to a
9690 token procured from @uref{https://github.com/settings/tokens} or
9694 @node Invoking guix lint
9695 @section Invoking @command{guix lint}
9697 @cindex @command{guix lint}
9698 @cindex package, checking for errors
9699 The @command{guix lint} command is meant to help package developers avoid
9700 common errors and use a consistent style. It runs a number of checks on
9701 a given set of packages in order to find common mistakes in their
9702 definitions. Available @dfn{checkers} include (see
9703 @code{--list-checkers} for a complete list):
9708 Validate certain typographical and stylistic rules about package
9709 descriptions and synopses.
9711 @item inputs-should-be-native
9712 Identify inputs that should most likely be native inputs.
9718 @itemx source-file-name
9719 Probe @code{home-page} and @code{source} URLs and report those that are
9720 invalid. Suggest a @code{mirror://} URL when applicable. If the
9721 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
9722 URL. Check that the source file name is meaningful, e.g.@: is not just a
9723 version number or ``git-checkout'', without a declared @code{file-name}
9724 (@pxref{origin Reference}).
9726 @item source-unstable-tarball
9727 Parse the @code{source} URL to determine if a tarball from GitHub is
9728 autogenerated or if it is a release tarball. Unfortunately GitHub's
9729 autogenerated tarballs are sometimes regenerated.
9732 @cindex Software Heritage, source code archive
9733 @cindex archival of source code, Software Heritage
9734 Checks whether the package's source code is archived at
9735 @uref{https://www.softwareheritage.org, Software Heritage}.
9737 When the source code that is not archived comes from a version-control system
9738 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
9739 ``save'' request so that it eventually archives it. This ensures that the
9740 source will remain available in the long term, and that Guix can fall back to
9741 Software Heritage should the source code disappear from its original host.
9742 The status of recent ``save'' requests can be
9743 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
9745 When source code is a tarball obtained with @code{url-fetch}, simply print a
9746 message when it is not archived. As of this writing, Software Heritage does
9747 not allow requests to save arbitrary tarballs; we are working on ways to
9748 ensure that non-VCS source code is also archived.
9751 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
9752 request rate per IP address}. When the limit is reached, @command{guix lint}
9753 prints a message and the @code{archival} checker stops doing anything until
9754 that limit has been reset.
9757 @cindex security vulnerabilities
9758 @cindex CVE, Common Vulnerabilities and Exposures
9759 Report known vulnerabilities found in the Common Vulnerabilities and
9760 Exposures (CVE) databases of the current and past year
9761 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
9764 To view information about a particular vulnerability, visit pages such as:
9768 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
9770 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
9774 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
9775 @code{CVE-2015-7554}.
9777 Package developers can specify in package recipes the
9778 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
9779 name and version of the package when they differ from the name or version
9780 that Guix uses, as in this example:
9786 ;; CPE calls this package "grub2".
9787 (properties '((cpe-name . "grub2")
9788 (cpe-version . "2.3"))))
9791 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
9792 Some entries in the CVE database do not specify which version of a
9793 package they apply to, and would thus ``stick around'' forever. Package
9794 developers who found CVE alerts and verified they can be ignored can
9795 declare them as in this example:
9801 ;; These CVEs no longer apply and can be safely ignored.
9802 (properties `((lint-hidden-cve . ("CVE-2011-0433"
9805 "CVE-2011-5244")))))
9809 Warn about obvious source code formatting issues: trailing white space,
9810 use of tabulations, etc.
9813 The general syntax is:
9816 guix lint @var{options} @var{package}@dots{}
9819 If no package is given on the command line, then all packages are checked.
9820 The @var{options} may be zero or more of the following:
9823 @item --list-checkers
9825 List and describe all the available checkers that will be run on packages
9830 Only enable the checkers specified in a comma-separated list using the
9831 names returned by @code{--list-checkers}.
9833 @item --load-path=@var{directory}
9834 @itemx -L @var{directory}
9835 Add @var{directory} to the front of the package module search path
9836 (@pxref{Package Modules}).
9838 This allows users to define their own packages and make them visible to
9839 the command-line tools.
9843 @node Invoking guix size
9844 @section Invoking @command{guix size}
9847 @cindex package size
9849 @cindex @command{guix size}
9850 The @command{guix size} command helps package developers profile the
9851 disk usage of packages. It is easy to overlook the impact of an
9852 additional dependency added to a package, or the impact of using a
9853 single output for a package that could easily be split (@pxref{Packages
9854 with Multiple Outputs}). Such are the typical issues that
9855 @command{guix size} can highlight.
9857 The command can be passed one or more package specifications
9858 such as @code{gcc@@4.8}
9859 or @code{guile:debug}, or a file name in the store. Consider this
9863 $ guix size coreutils
9864 store item total self
9865 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
9866 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
9867 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
9868 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
9869 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
9870 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
9871 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
9872 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
9877 The store items listed here constitute the @dfn{transitive closure} of
9878 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
9879 would be returned by:
9882 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
9885 Here the output shows three columns next to store items. The first column,
9886 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
9887 the store item---that is, its own size plus the size of all its
9888 dependencies. The next column, labeled ``self'', shows the size of the
9889 item itself. The last column shows the ratio of the size of the item
9890 itself to the space occupied by all the items listed here.
9892 In this example, we see that the closure of Coreutils weighs in at
9893 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
9894 libraries. (That libc and GCC's libraries represent a large fraction of
9895 the closure is not a problem @i{per se} because they are always available
9896 on the system anyway.)
9898 When the package(s) passed to @command{guix size} are available in the
9899 store@footnote{More precisely, @command{guix size} looks for the
9900 @emph{ungrafted} variant of the given package(s), as returned by
9901 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
9902 for information on grafts.}, @command{guix size} queries the daemon to determine its
9903 dependencies, and measures its size in the store, similar to @command{du
9904 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
9907 When the given packages are @emph{not} in the store, @command{guix size}
9908 reports information based on the available substitutes
9909 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
9910 store items that are not even on disk, only available remotely.
9912 You can also specify several package names:
9915 $ guix size coreutils grep sed bash
9916 store item total self
9917 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
9918 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
9919 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
9920 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
9926 In this example we see that the combination of the four packages takes
9927 102.3@tie{}MiB in total, which is much less than the sum of each closure
9928 since they have a lot of dependencies in common.
9930 The available options are:
9934 @item --substitute-urls=@var{urls}
9935 Use substitute information from @var{urls}.
9936 @xref{client-substitute-urls, the same option for @code{guix build}}.
9938 @item --sort=@var{key}
9939 Sort lines according to @var{key}, one of the following options:
9943 the size of each item (the default);
9945 the total size of the item's closure.
9948 @item --map-file=@var{file}
9949 Write a graphical map of disk usage in PNG format to @var{file}.
9951 For the example above, the map looks like this:
9953 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
9954 produced by @command{guix size}}
9956 This option requires that
9957 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
9958 installed and visible in Guile's module search path. When that is not
9959 the case, @command{guix size} fails as it tries to load it.
9961 @item --system=@var{system}
9962 @itemx -s @var{system}
9963 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
9965 @item --load-path=@var{directory}
9966 @itemx -L @var{directory}
9967 Add @var{directory} to the front of the package module search path
9968 (@pxref{Package Modules}).
9970 This allows users to define their own packages and make them visible to
9971 the command-line tools.
9974 @node Invoking guix graph
9975 @section Invoking @command{guix graph}
9978 @cindex @command{guix graph}
9979 @cindex package dependencies
9980 Packages and their dependencies form a @dfn{graph}, specifically a
9981 directed acyclic graph (DAG). It can quickly become difficult to have a
9982 mental model of the package DAG, so the @command{guix graph} command
9983 provides a visual representation of the DAG. By default,
9984 @command{guix graph} emits a DAG representation in the input format of
9985 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
9986 directly to the @command{dot} command of Graphviz. It can also emit an
9987 HTML page with embedded JavaScript code to display a ``chord diagram''
9988 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
9989 emit Cypher queries to construct a graph in a graph database supporting
9990 the @uref{https://www.opencypher.org/, openCypher} query language.
9991 The general syntax is:
9994 guix graph @var{options} @var{package}@dots{}
9997 For example, the following command generates a PDF file representing the
9998 package DAG for the GNU@tie{}Core Utilities, showing its build-time
10002 guix graph coreutils | dot -Tpdf > dag.pdf
10005 The output looks like this:
10007 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
10009 Nice little graph, no?
10011 But there is more than one graph! The one above is concise: it is the
10012 graph of package objects, omitting implicit inputs such as GCC, libc,
10013 grep, etc. It is often useful to have such a concise graph, but
10014 sometimes one may want to see more details. @command{guix graph} supports
10015 several types of graphs, allowing you to choose the level of detail:
10019 This is the default type used in the example above. It shows the DAG of
10020 package objects, excluding implicit dependencies. It is concise, but
10021 filters out many details.
10023 @item reverse-package
10024 This shows the @emph{reverse} DAG of packages. For example:
10027 guix graph --type=reverse-package ocaml
10030 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
10031 you are also interested in cases where OCaml is an implicit dependency, see
10032 @code{reverse-bag} below.)
10034 Note that for core packages this can yield huge graphs. If all you want
10035 is to know the number of packages that depend on a given package, use
10036 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
10037 @option{--list-dependent}}).
10040 This is the package DAG, @emph{including} implicit inputs.
10042 For instance, the following command:
10045 guix graph --type=bag-emerged coreutils | dot -Tpdf > dag.pdf
10048 ...@: yields this bigger graph:
10050 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
10052 At the bottom of the graph, we see all the implicit inputs of
10053 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
10055 Now, note that the dependencies of these implicit inputs---that is, the
10056 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
10057 here, for conciseness.
10060 Similar to @code{bag-emerged}, but this time including all the bootstrap
10063 @item bag-with-origins
10064 Similar to @code{bag}, but also showing origins and their dependencies.
10067 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
10068 it also takes implicit dependencies into account. For example:
10071 guix graph -t reverse-bag dune
10075 ...@: yields the graph of all packages that depend on Dune, directly or
10076 indirectly. Since Dune is an @emph{implicit} dependency of many packages
10077 @i{via} @code{dune-build-system}, this shows a large number of packages,
10078 whereas @code{reverse-package} would show very few if any.
10081 This is the most detailed representation: It shows the DAG of
10082 derivations (@pxref{Derivations}) and plain store items. Compared to
10083 the above representation, many additional nodes are visible, including
10084 build scripts, patches, Guile modules, etc.
10086 For this type of graph, it is also possible to pass a @file{.drv} file
10087 name instead of a package name, as in:
10090 guix graph -t derivation `guix system build -d my-config.scm`
10094 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
10095 For example, the following command shows the graph for the package
10096 module that defines the @code{guile} package:
10099 guix graph -t module guile | dot -Tpdf > module-graph.pdf
10103 All the types above correspond to @emph{build-time dependencies}. The
10104 following graph type represents the @emph{run-time dependencies}:
10108 This is the graph of @dfn{references} of a package output, as returned
10109 by @command{guix gc --references} (@pxref{Invoking guix gc}).
10111 If the given package output is not available in the store, @command{guix
10112 graph} attempts to obtain dependency information from substitutes.
10114 Here you can also pass a store file name instead of a package name. For
10115 example, the command below produces the reference graph of your profile
10116 (which can be big!):
10119 guix graph -t references `readlink -f ~/.guix-profile`
10123 This is the graph of the @dfn{referrers} of a store item, as returned by
10124 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
10126 This relies exclusively on local information from your store. For
10127 instance, let us suppose that the current Inkscape is available in 10
10128 profiles on your machine; @command{guix graph -t referrers inkscape}
10129 will show a graph rooted at Inkscape and with those 10 profiles linked
10132 It can help determine what is preventing a store item from being garbage
10137 The available options are the following:
10140 @item --type=@var{type}
10141 @itemx -t @var{type}
10142 Produce a graph output of @var{type}, where @var{type} must be one of
10143 the values listed above.
10146 List the supported graph types.
10148 @item --backend=@var{backend}
10149 @itemx -b @var{backend}
10150 Produce a graph using the selected @var{backend}.
10152 @item --list-backends
10153 List the supported graph backends.
10155 Currently, the available backends are Graphviz and d3.js.
10157 @item --expression=@var{expr}
10158 @itemx -e @var{expr}
10159 Consider the package @var{expr} evaluates to.
10161 This is useful to precisely refer to a package, as in this example:
10164 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
10167 @item --system=@var{system}
10168 @itemx -s @var{system}
10169 Display the graph for @var{system}---e.g., @code{i686-linux}.
10171 The package dependency graph is largely architecture-independent, but there
10172 are some architecture-dependent bits that this option allows you to visualize.
10174 @item --load-path=@var{directory}
10175 @itemx -L @var{directory}
10176 Add @var{directory} to the front of the package module search path
10177 (@pxref{Package Modules}).
10179 This allows users to define their own packages and make them visible to
10180 the command-line tools.
10183 On top of that, @command{guix graph} supports all the usual package
10184 transformation options (@pxref{Package Transformation Options}). This
10185 makes it easy to view the effect of a graph-rewriting transformation
10186 such as @option{--with-input}. For example, the command below outputs
10187 the graph of @code{git} once @code{openssl} has been replaced by
10188 @code{libressl} everywhere in the graph:
10191 guix graph git --with-input=openssl=libressl
10194 So many possibilities, so much fun!
10196 @node Invoking guix publish
10197 @section Invoking @command{guix publish}
10199 @cindex @command{guix publish}
10200 The purpose of @command{guix publish} is to enable users to easily share
10201 their store with others, who can then use it as a substitute server
10202 (@pxref{Substitutes}).
10204 When @command{guix publish} runs, it spawns an HTTP server which allows
10205 anyone with network access to obtain substitutes from it. This means
10206 that any machine running Guix can also act as if it were a build farm,
10207 since the HTTP interface is compatible with Cuirass, the software behind
10208 the @code{@value{SUBSTITUTE-SERVER}} build farm.
10210 For security, each substitute is signed, allowing recipients to check
10211 their authenticity and integrity (@pxref{Substitutes}). Because
10212 @command{guix publish} uses the signing key of the system, which is only
10213 readable by the system administrator, it must be started as root; the
10214 @code{--user} option makes it drop root privileges early on.
10216 The signing key pair must be generated before @command{guix publish} is
10217 launched, using @command{guix archive --generate-key} (@pxref{Invoking
10220 The general syntax is:
10223 guix publish @var{options}@dots{}
10226 Running @command{guix publish} without any additional arguments will
10227 spawn an HTTP server on port 8080:
10233 Once a publishing server has been authorized (@pxref{Invoking guix
10234 archive}), the daemon may download substitutes from it:
10237 guix-daemon --substitute-urls=http://example.org:8080
10240 By default, @command{guix publish} compresses archives on the fly as it
10241 serves them. This ``on-the-fly'' mode is convenient in that it requires
10242 no setup and is immediately available. However, when serving lots of
10243 clients, we recommend using the @option{--cache} option, which enables
10244 caching of the archives before they are sent to clients---see below for
10245 details. The @command{guix weather} command provides a handy way to
10246 check what a server provides (@pxref{Invoking guix weather}).
10248 As a bonus, @command{guix publish} also serves as a content-addressed
10249 mirror for source files referenced in @code{origin} records
10250 (@pxref{origin Reference}). For instance, assuming @command{guix
10251 publish} is running on @code{example.org}, the following URL returns the
10252 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
10253 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
10256 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
10259 Obviously, these URLs only work for files that are in the store; in
10260 other cases, they return 404 (``Not Found'').
10262 @cindex build logs, publication
10263 Build logs are available from @code{/log} URLs like:
10266 http://example.org/log/gwspk@dots{}-guile-2.2.3
10270 When @command{guix-daemon} is configured to save compressed build logs,
10271 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
10272 URLs return the compressed log as-is, with an appropriate
10273 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
10274 running @command{guix-daemon} with @code{--log-compression=gzip} since
10275 Web browsers can automatically decompress it, which is not the case with
10278 The following options are available:
10281 @item --port=@var{port}
10282 @itemx -p @var{port}
10283 Listen for HTTP requests on @var{port}.
10285 @item --listen=@var{host}
10286 Listen on the network interface for @var{host}. The default is to
10287 accept connections from any interface.
10289 @item --user=@var{user}
10290 @itemx -u @var{user}
10291 Change privileges to @var{user} as soon as possible---i.e., once the
10292 server socket is open and the signing key has been read.
10294 @item --compression[=@var{method}[:@var{level}]]
10295 @itemx -C [@var{method}[:@var{level}]]
10296 Compress data using the given @var{method} and @var{level}. @var{method} is
10297 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
10300 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
10301 to different compression levels: 1 is the fastest, and 9 is the best
10302 (CPU-intensive). The default is 3.
10304 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
10305 increase in CPU usage; see
10306 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
10309 Unless @option{--cache} is used, compression occurs on the fly and
10310 the compressed streams are not
10311 cached. Thus, to reduce load on the machine that runs @command{guix
10312 publish}, it may be a good idea to choose a low compression level, to
10313 run @command{guix publish} behind a caching proxy, or to use
10314 @option{--cache}. Using @option{--cache} has the advantage that it
10315 allows @command{guix publish} to add @code{Content-Length} HTTP header
10318 This option can be repeated, in which case every substitute gets compressed
10319 using all the selected methods, and all of them are advertised. This is
10320 useful when users may not support all the compression methods: they can select
10321 the one they support.
10323 @item --cache=@var{directory}
10324 @itemx -c @var{directory}
10325 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
10326 and only serve archives that are in cache.
10328 When this option is omitted, archives and meta-data are created
10329 on-the-fly. This can reduce the available bandwidth, especially when
10330 compression is enabled, since this may become CPU-bound. Another
10331 drawback of the default mode is that the length of archives is not known
10332 in advance, so @command{guix publish} does not add a
10333 @code{Content-Length} HTTP header to its responses, which in turn
10334 prevents clients from knowing the amount of data being downloaded.
10336 Conversely, when @option{--cache} is used, the first request for a store
10337 item (@i{via} a @code{.narinfo} URL) returns 404 and triggers a
10338 background process to @dfn{bake} the archive---computing its
10339 @code{.narinfo} and compressing the archive, if needed. Once the
10340 archive is cached in @var{directory}, subsequent requests succeed and
10341 are served directly from the cache, which guarantees that clients get
10342 the best possible bandwidth.
10344 The ``baking'' process is performed by worker threads. By default, one
10345 thread per CPU core is created, but this can be customized. See
10346 @option{--workers} below.
10348 When @option{--ttl} is used, cached entries are automatically deleted
10349 when they have expired.
10351 @item --workers=@var{N}
10352 When @option{--cache} is used, request the allocation of @var{N} worker
10353 threads to ``bake'' archives.
10355 @item --ttl=@var{ttl}
10356 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
10357 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
10358 days, @code{1m} means 1 month, and so on.
10360 This allows the user's Guix to keep substitute information in cache for
10361 @var{ttl}. However, note that @code{guix publish} does not itself
10362 guarantee that the store items it provides will indeed remain available
10363 for as long as @var{ttl}.
10365 Additionally, when @option{--cache} is used, cached entries that have
10366 not been accessed for @var{ttl} and that no longer have a corresponding
10367 item in the store, may be deleted.
10369 @item --nar-path=@var{path}
10370 Use @var{path} as the prefix for the URLs of ``nar'' files
10371 (@pxref{Invoking guix archive, normalized archives}).
10373 By default, nars are served at a URL such as
10374 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
10375 change the @code{/nar} part to @var{path}.
10377 @item --public-key=@var{file}
10378 @itemx --private-key=@var{file}
10379 Use the specific @var{file}s as the public/private key pair used to sign
10380 the store items being published.
10382 The files must correspond to the same key pair (the private key is used
10383 for signing and the public key is merely advertised in the signature
10384 metadata). They must contain keys in the canonical s-expression format
10385 as produced by @command{guix archive --generate-key} (@pxref{Invoking
10386 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
10387 @file{/etc/guix/signing-key.sec} are used.
10389 @item --repl[=@var{port}]
10390 @itemx -r [@var{port}]
10391 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
10392 Reference Manual}) on @var{port} (37146 by default). This is used
10393 primarily for debugging a running @command{guix publish} server.
10396 Enabling @command{guix publish} on Guix System is a one-liner: just
10397 instantiate a @code{guix-publish-service-type} service in the @code{services} field
10398 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
10399 @code{guix-publish-service-type}}).
10401 If you are instead running Guix on a ``foreign distro'', follow these
10406 If your host distro uses the systemd init system:
10409 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
10410 /etc/systemd/system/
10411 # systemctl start guix-publish && systemctl enable guix-publish
10415 If your host distro uses the Upstart init system:
10418 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
10419 # start guix-publish
10423 Otherwise, proceed similarly with your distro's init system.
10426 @node Invoking guix challenge
10427 @section Invoking @command{guix challenge}
10429 @cindex reproducible builds
10430 @cindex verifiable builds
10431 @cindex @command{guix challenge}
10433 Do the binaries provided by this server really correspond to the source
10434 code it claims to build? Is a package build process deterministic?
10435 These are the questions the @command{guix challenge} command attempts to
10438 The former is obviously an important question: Before using a substitute
10439 server (@pxref{Substitutes}), one had better @emph{verify} that it
10440 provides the right binaries, and thus @emph{challenge} it. The latter
10441 is what enables the former: If package builds are deterministic, then
10442 independent builds of the package should yield the exact same result,
10443 bit for bit; if a server provides a binary different from the one
10444 obtained locally, it may be either corrupt or malicious.
10446 We know that the hash that shows up in @file{/gnu/store} file names is
10447 the hash of all the inputs of the process that built the file or
10448 directory---compilers, libraries, build scripts,
10449 etc. (@pxref{Introduction}). Assuming deterministic build processes,
10450 one store file name should map to exactly one build output.
10451 @command{guix challenge} checks whether there is, indeed, a single
10452 mapping by comparing the build outputs of several independent builds of
10453 any given store item.
10455 The command output looks like this:
10458 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10459 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
10460 updating list of substitutes from 'https://guix.example.org'... 100.0%
10461 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
10462 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10463 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
10464 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
10466 /lib/libcrypto.so.1.1
10469 /gnu/store/@dots{}-git-2.5.0 contents differ:
10470 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
10471 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
10472 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
10474 /libexec/git-core/git-fsck
10476 /gnu/store/@dots{}-pius-2.1.1 contents differ:
10477 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10478 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
10479 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
10481 /share/man/man1/pius.1.gz
10485 6,406 store items were analyzed:
10486 - 4,749 (74.1%) were identical
10487 - 525 (8.2%) differed
10488 - 1,132 (17.7%) were inconclusive
10492 In this example, @command{guix challenge} first scans the store to
10493 determine the set of locally-built derivations---as opposed to store
10494 items that were downloaded from a substitute server---and then queries
10495 all the substitute servers. It then reports those store items for which
10496 the servers obtained a result different from the local build.
10498 @cindex non-determinism, in package builds
10499 As an example, @code{guix.example.org} always gets a different answer.
10500 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
10501 case of Git. This might indicate that the build process of Git is
10502 non-deterministic, meaning that its output varies as a function of
10503 various things that Guix does not fully control, in spite of building
10504 packages in isolated environments (@pxref{Features}). Most common
10505 sources of non-determinism include the addition of timestamps in build
10506 results, the inclusion of random numbers, and directory listings sorted
10507 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
10510 To find out what is wrong with this Git binary, the easiest approach is
10514 guix challenge git \
10515 --diff=diffoscope \
10516 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
10519 This automatically invokes @command{diffoscope}, which displays detailed
10520 information about files that differ.
10522 Alternately, we can do something along these lines (@pxref{Invoking guix
10526 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0 \
10527 | guix archive -x /tmp/git
10528 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
10531 This command shows the difference between the files resulting from the
10532 local build, and the files resulting from the build on
10533 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
10534 diffutils, Comparing and Merging Files}). The @command{diff} command
10535 works great for text files. When binary files differ, a better option
10536 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
10537 visualize differences for all kinds of files.
10539 Once you have done that work, you can tell whether the differences are due
10540 to a non-deterministic build process or to a malicious server. We try
10541 hard to remove sources of non-determinism in packages to make it easier
10542 to verify substitutes, but of course, this is a process that
10543 involves not just Guix, but a large part of the free software community.
10544 In the meantime, @command{guix challenge} is one tool to help address
10547 If you are writing packages for Guix, you are encouraged to check
10548 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
10549 same build result as you did with:
10552 $ guix challenge @var{package}
10556 where @var{package} is a package specification such as
10557 @code{guile@@2.0} or @code{glibc:debug}.
10559 The general syntax is:
10562 guix challenge @var{options} [@var{packages}@dots{}]
10565 When a difference is found between the hash of a locally-built item and
10566 that of a server-provided substitute, or among substitutes provided by
10567 different servers, the command displays it as in the example above and
10568 its exit code is 2 (other non-zero exit codes denote other kinds of
10571 The one option that matters is:
10575 @item --substitute-urls=@var{urls}
10576 Consider @var{urls} the whitespace-separated list of substitute source
10577 URLs to compare to.
10579 @item --diff=@var{mode}
10580 Upon mismatches, show differences according to @var{mode}, one of:
10583 @item @code{simple} (the default)
10584 Show the list of files that differ.
10586 @item @code{diffoscope}
10587 @itemx @var{command}
10588 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
10589 two directories whose contents do not match.
10591 When @var{command} is an absolute file name, run @var{command} instead
10595 Do not show further details about the differences.
10598 Thus, unless @code{--diff=none} is passed, @command{guix challenge}
10599 downloads the store items from the given substitute servers so that it
10604 Show details about matches (identical contents) in addition to
10605 information about mismatches.
10609 @node Invoking guix copy
10610 @section Invoking @command{guix copy}
10612 @cindex copy, of store items, over SSH
10613 @cindex SSH, copy of store items
10614 @cindex sharing store items across machines
10615 @cindex transferring store items across machines
10616 The @command{guix copy} command copies items from the store of one
10617 machine to that of another machine over a secure shell (SSH)
10618 connection@footnote{This command is available only when Guile-SSH was
10619 found. @xref{Requirements}, for details.}. For example, the following
10620 command copies the @code{coreutils} package, the user's profile, and all
10621 their dependencies over to @var{host}, logged in as @var{user}:
10624 guix copy --to=@var{user}@@@var{host} \
10625 coreutils `readlink -f ~/.guix-profile`
10628 If some of the items to be copied are already present on @var{host},
10629 they are not actually sent.
10631 The command below retrieves @code{libreoffice} and @code{gimp} from
10632 @var{host}, assuming they are available there:
10635 guix copy --from=@var{host} libreoffice gimp
10638 The SSH connection is established using the Guile-SSH client, which is
10639 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
10640 @file{~/.ssh/config}, and uses the SSH agent for authentication.
10642 The key used to sign items that are sent must be accepted by the remote
10643 machine. Likewise, the key used by the remote machine to sign items you
10644 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
10645 own daemon. @xref{Invoking guix archive}, for more information about
10646 store item authentication.
10648 The general syntax is:
10651 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
10654 You must always specify one of the following options:
10657 @item --to=@var{spec}
10658 @itemx --from=@var{spec}
10659 Specify the host to send to or receive from. @var{spec} must be an SSH
10660 spec such as @code{example.org}, @code{charlie@@example.org}, or
10661 @code{charlie@@example.org:2222}.
10664 The @var{items} can be either package names, such as @code{gimp}, or
10665 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
10667 When specifying the name of a package to send, it is first built if
10668 needed, unless @option{--dry-run} was specified. Common build options
10669 are supported (@pxref{Common Build Options}).
10672 @node Invoking guix container
10673 @section Invoking @command{guix container}
10675 @cindex @command{guix container}
10677 As of version @value{VERSION}, this tool is experimental. The interface
10678 is subject to radical change in the future.
10681 The purpose of @command{guix container} is to manipulate processes
10682 running within an isolated environment, commonly known as a
10683 ``container'', typically created by the @command{guix environment}
10684 (@pxref{Invoking guix environment}) and @command{guix system container}
10685 (@pxref{Invoking guix system}) commands.
10687 The general syntax is:
10690 guix container @var{action} @var{options}@dots{}
10693 @var{action} specifies the operation to perform with a container, and
10694 @var{options} specifies the context-specific arguments for the action.
10696 The following actions are available:
10700 Execute a command within the context of a running container.
10705 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
10708 @var{pid} specifies the process ID of the running container.
10709 @var{program} specifies an executable file name within the root file
10710 system of the container. @var{arguments} are the additional options that
10711 will be passed to @var{program}.
10713 The following command launches an interactive login shell inside a
10714 Guix system container, started by @command{guix system container}, and whose
10715 process ID is 9001:
10718 guix container exec 9001 /run/current-system/profile/bin/bash --login
10721 Note that the @var{pid} cannot be the parent process of a container. It
10722 must be PID 1 of the container or one of its child processes.
10726 @node Invoking guix weather
10727 @section Invoking @command{guix weather}
10729 Occasionally you're grumpy because substitutes are lacking and you end
10730 up building packages by yourself (@pxref{Substitutes}). The
10731 @command{guix weather} command reports on substitute availability on the
10732 specified servers so you can have an idea of whether you'll be grumpy
10733 today. It can sometimes be useful info as a user, but it is primarily
10734 useful to people running @command{guix publish} (@pxref{Invoking guix
10737 @cindex statistics, for substitutes
10738 @cindex availability of substitutes
10739 @cindex substitute availability
10740 @cindex weather, substitute availability
10741 Here's a sample run:
10744 $ guix weather --substitute-urls=https://guix.example.org
10745 computing 5,872 package derivations for x86_64-linux...
10746 looking for 6,128 store items on https://guix.example.org..
10747 updating list of substitutes from 'https://guix.example.org'... 100.0%
10748 https://guix.example.org
10749 43.4% substitutes available (2,658 out of 6,128)
10750 7,032.5 MiB of nars (compressed)
10751 19,824.2 MiB on disk (uncompressed)
10752 0.030 seconds per request (182.9 seconds in total)
10753 33.5 requests per second
10755 9.8% (342 out of 3,470) of the missing items are queued
10757 x86_64-linux: 518 (59.7%)
10758 i686-linux: 221 (25.5%)
10759 aarch64-linux: 128 (14.8%)
10760 build rate: 23.41 builds per hour
10761 x86_64-linux: 11.16 builds per hour
10762 i686-linux: 6.03 builds per hour
10763 aarch64-linux: 6.41 builds per hour
10766 @cindex continuous integration, statistics
10767 As you can see, it reports the fraction of all the packages for which
10768 substitutes are available on the server---regardless of whether
10769 substitutes are enabled, and regardless of whether this server's signing
10770 key is authorized. It also reports the size of the compressed archives
10771 (``nars'') provided by the server, the size the corresponding store
10772 items occupy in the store (assuming deduplication is turned off), and
10773 the server's throughput. The second part gives continuous integration
10774 (CI) statistics, if the server supports it. In addition, using the
10775 @option{--coverage} option, @command{guix weather} can list ``important''
10776 package substitutes missing on the server (see below).
10778 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
10779 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
10780 challenge}, it ignores signatures on those substitutes, which is
10781 innocuous since the command only gathers statistics and cannot install
10784 The general syntax is:
10787 guix weather @var{options}@dots{} [@var{packages}@dots{}]
10790 When @var{packages} is omitted, @command{guix weather} checks the availability
10791 of substitutes for @emph{all} the packages, or for those specified with
10792 @option{--manifest}; otherwise it only considers the specified packages. It
10793 is also possible to query specific system types with @option{--system}. The
10794 available options are listed below.
10797 @item --substitute-urls=@var{urls}
10798 @var{urls} is the space-separated list of substitute server URLs to
10799 query. When this option is omitted, the default set of substitute
10800 servers is queried.
10802 @item --system=@var{system}
10803 @itemx -s @var{system}
10804 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
10805 option can be repeated, in which case @command{guix weather} will query
10806 substitutes for several system types.
10808 @item --manifest=@var{file}
10809 Instead of querying substitutes for all the packages, only ask for those
10810 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
10811 with the @code{-m} option of @command{guix package} (@pxref{Invoking
10814 @item --coverage[=@var{count}]
10815 @itemx -c [@var{count}]
10816 Report on substitute coverage for packages: list packages with at least
10817 @var{count} dependents (zero by default) for which substitutes are
10818 unavailable. Dependent packages themselves are not listed: if @var{b} depends
10819 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
10820 @var{b} usually lacks substitutes as well. The result looks like this:
10823 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
10824 computing 8,983 package derivations for x86_64-linux...
10825 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
10826 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
10827 @value{SUBSTITUTE-URL}
10828 64.7% substitutes available (6,047 out of 9,343)
10830 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
10831 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
10832 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
10833 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
10837 What this example shows is that @code{kcoreaddons} and presumably the 58
10838 packages that depend on it have no substitutes at @code{ci.guix.info};
10839 likewise for @code{qgpgme} and the 46 packages that depend on it.
10841 If you are a Guix developer, or if you are taking care of this build farm,
10842 you'll probably want to have a closer look at these packages: they may simply
10846 @node Invoking guix processes
10847 @section Invoking @command{guix processes}
10849 The @command{guix processes} command can be useful to developers and system
10850 administrators, especially on multi-user machines and on build farms: it lists
10851 the current sessions (connections to the daemon), as well as information about
10852 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
10853 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
10854 listed.}. Here's an example of the information it returns:
10857 $ sudo guix processes
10860 ClientCommand: guix environment --ad-hoc python
10864 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
10868 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10869 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
10870 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
10871 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
10872 ChildProcess: 20495: guix offload x86_64-linux 7200 1 28800
10873 ChildProcess: 27733: guix offload x86_64-linux 7200 1 28800
10874 ChildProcess: 27793: guix offload x86_64-linux 7200 1 28800
10877 In this example we see that @command{guix-daemon} has three clients:
10878 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
10879 integration tool; their process identifier (PID) is given by the
10880 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
10881 @command{guix-daemon} sub-process of this particular session.
10883 The @code{LockHeld} fields show which store items are currently locked by this
10884 session, which corresponds to store items being built or substituted (the
10885 @code{LockHeld} field is not displayed when @command{guix processes} is not
10886 running as root.) Last, by looking at the @code{ChildProcess} field, we
10887 understand that these three builds are being offloaded (@pxref{Daemon Offload
10890 The output is in Recutils format so we can use the handy @command{recsel}
10891 command to select sessions of interest (@pxref{Selection Expressions,,,
10892 recutils, GNU recutils manual}). As an example, the command shows the command
10893 line and PID of the client that triggered the build of a Perl package:
10896 $ sudo guix processes | \
10897 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
10899 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
10902 @node System Configuration
10903 @chapter System Configuration
10905 @cindex system configuration
10906 Guix System supports a consistent whole-system configuration
10907 mechanism. By that we mean that all aspects of the global system
10908 configuration---such as the available system services, timezone and
10909 locale settings, user accounts---are declared in a single place. Such
10910 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
10912 One of the advantages of putting all the system configuration under the
10913 control of Guix is that it supports transactional system upgrades, and
10914 makes it possible to roll back to a previous system instantiation,
10915 should something go wrong with the new one (@pxref{Features}). Another
10916 advantage is that it makes it easy to replicate the exact same configuration
10917 across different machines, or at different points in time, without
10918 having to resort to additional administration tools layered on top of
10919 the own tools of the system.
10920 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
10922 This section describes this mechanism. First we focus on the system
10923 administrator's viewpoint---explaining how the system is configured and
10924 instantiated. Then we show how this mechanism can be extended, for
10925 instance to support new system services.
10928 * Using the Configuration System:: Customizing your GNU system.
10929 * operating-system Reference:: Detail of operating-system declarations.
10930 * File Systems:: Configuring file system mounts.
10931 * Mapped Devices:: Block device extra processing.
10932 * User Accounts:: Specifying user accounts.
10933 * Keyboard Layout:: How the system interprets key strokes.
10934 * Locales:: Language and cultural convention settings.
10935 * Services:: Specifying system services.
10936 * Setuid Programs:: Programs running with root privileges.
10937 * X.509 Certificates:: Authenticating HTTPS servers.
10938 * Name Service Switch:: Configuring libc's name service switch.
10939 * Initial RAM Disk:: Linux-Libre bootstrapping.
10940 * Bootloader Configuration:: Configuring the boot loader.
10941 * Invoking guix system:: Instantiating a system configuration.
10942 * Invoking guix deploy:: Deploying a system configuration to a remote host.
10943 * Running Guix in a VM:: How to run Guix System in a virtual machine.
10944 * Defining Services:: Adding new service definitions.
10947 @node Using the Configuration System
10948 @section Using the Configuration System
10950 The operating system is configured by providing an
10951 @code{operating-system} declaration in a file that can then be passed to
10952 the @command{guix system} command (@pxref{Invoking guix system}). A
10953 simple setup, with the default system services, the default Linux-Libre
10954 kernel, initial RAM disk, and boot loader looks like this:
10956 @findex operating-system
10958 @include os-config-bare-bones.texi
10961 This example should be self-describing. Some of the fields defined
10962 above, such as @code{host-name} and @code{bootloader}, are mandatory.
10963 Others, such as @code{packages} and @code{services}, can be omitted, in
10964 which case they get a default value.
10966 Below we discuss the effect of some of the most important fields
10967 (@pxref{operating-system Reference}, for details about all the available
10968 fields), and how to @dfn{instantiate} the operating system using
10969 @command{guix system}.
10971 @unnumberedsubsec Bootloader
10973 @cindex legacy boot, on Intel machines
10974 @cindex BIOS boot, on Intel machines
10977 The @code{bootloader} field describes the method that will be used to boot
10978 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
10979 mode, as in the example above. However, more recent machines rely instead on
10980 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
10981 the @code{bootloader} field should contain something along these lines:
10984 (bootloader-configuration
10985 (bootloader grub-efi-bootloader)
10986 (target "/boot/efi"))
10989 @xref{Bootloader Configuration}, for more information on the available
10990 configuration options.
10992 @unnumberedsubsec Globally-Visible Packages
10994 @vindex %base-packages
10995 The @code{packages} field lists packages that will be globally visible
10996 on the system, for all user accounts---i.e., in every user's @code{PATH}
10997 environment variable---in addition to the per-user profiles
10998 (@pxref{Invoking guix package}). The @code{%base-packages} variable
10999 provides all the tools one would expect for basic user and administrator
11000 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
11001 the GNU Zile lightweight text editor, @command{find}, @command{grep},
11002 etc. The example above adds GNU@tie{}Screen to those,
11003 taken from the @code{(gnu packages screen)}
11004 module (@pxref{Package Modules}). The
11005 @code{(list package output)} syntax can be used to add a specific output
11009 (use-modules (gnu packages))
11010 (use-modules (gnu packages dns))
11014 (packages (cons (list bind "utils")
11018 @findex specification->package
11019 Referring to packages by variable name, like @code{bind} above, has
11020 the advantage of being unambiguous; it also allows typos and such to be
11021 diagnosed right away as ``unbound variables''. The downside is that one
11022 needs to know which module defines which package, and to augment the
11023 @code{use-package-modules} line accordingly. To avoid that, one can use
11024 the @code{specification->package} procedure of the @code{(gnu packages)}
11025 module, which returns the best package for a given name or name and
11029 (use-modules (gnu packages))
11033 (packages (append (map specification->package
11034 '("tcpdump" "htop" "gnupg@@2.0"))
11038 @unnumberedsubsec System Services
11041 @vindex %base-services
11042 The @code{services} field lists @dfn{system services} to be made
11043 available when the system starts (@pxref{Services}).
11044 The @code{operating-system} declaration above specifies that, in
11045 addition to the basic services, we want the OpenSSH secure shell
11046 daemon listening on port 2222 (@pxref{Networking Services,
11047 @code{openssh-service-type}}). Under the hood,
11048 @code{openssh-service-type} arranges so that @command{sshd} is started with the
11049 right command-line options, possibly with supporting configuration files
11050 generated as needed (@pxref{Defining Services}).
11052 @cindex customization, of services
11053 @findex modify-services
11054 Occasionally, instead of using the base services as is, you will want to
11055 customize them. To do this, use @code{modify-services} (@pxref{Service
11056 Reference, @code{modify-services}}) to modify the list.
11058 For example, suppose you want to modify @code{guix-daemon} and Mingetty
11059 (the console log-in) in the @code{%base-services} list (@pxref{Base
11060 Services, @code{%base-services}}). To do that, you can write the
11061 following in your operating system declaration:
11064 (define %my-services
11065 ;; My very own list of services.
11066 (modify-services %base-services
11067 (guix-service-type config =>
11068 (guix-configuration
11070 (use-substitutes? #f)
11071 (extra-options '("--gc-keep-derivations"))))
11072 (mingetty-service-type config =>
11073 (mingetty-configuration
11074 (inherit config)))))
11078 (services %my-services))
11081 This changes the configuration---i.e., the service parameters---of the
11082 @code{guix-service-type} instance, and that of all the
11083 @code{mingetty-service-type} instances in the @code{%base-services} list.
11084 Observe how this is accomplished: first, we arrange for the original
11085 configuration to be bound to the identifier @code{config} in the
11086 @var{body}, and then we write the @var{body} so that it evaluates to the
11087 desired configuration. In particular, notice how we use @code{inherit}
11088 to create a new configuration which has the same values as the old
11089 configuration, but with a few modifications.
11091 @cindex encrypted disk
11092 The configuration for a typical ``desktop'' usage, with an encrypted
11093 root partition, the X11 display
11094 server, GNOME and Xfce (users can choose which of these desktop
11095 environments to use at the log-in screen by pressing @kbd{F1}), network
11096 management, power management, and more, would look like this:
11099 @include os-config-desktop.texi
11102 A graphical system with a choice of lightweight window managers
11103 instead of full-blown desktop environments would look like this:
11106 @include os-config-lightweight-desktop.texi
11109 This example refers to the @file{/boot/efi} file system by its UUID,
11110 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
11111 as returned by the @command{blkid} command.
11113 @xref{Desktop Services}, for the exact list of services provided by
11114 @code{%desktop-services}. @xref{X.509 Certificates}, for background
11115 information about the @code{nss-certs} package that is used here.
11117 Again, @code{%desktop-services} is just a list of service objects. If
11118 you want to remove services from there, you can do so using the
11119 procedures for list filtering (@pxref{SRFI-1 Filtering and
11120 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
11121 following expression returns a list that contains all the services in
11122 @code{%desktop-services} minus the Avahi service:
11125 (remove (lambda (service)
11126 (eq? (service-kind service) avahi-service-type))
11130 @unnumberedsubsec Instantiating the System
11132 Assuming the @code{operating-system} declaration
11133 is stored in the @file{my-system-config.scm}
11134 file, the @command{guix system reconfigure my-system-config.scm} command
11135 instantiates that configuration, and makes it the default GRUB boot
11136 entry (@pxref{Invoking guix system}).
11138 The normal way to change the system configuration is by updating this
11139 file and re-running @command{guix system reconfigure}. One should never
11140 have to touch files in @file{/etc} or to run commands that modify the
11141 system state such as @command{useradd} or @command{grub-install}. In
11142 fact, you must avoid that since that would not only void your warranty
11143 but also prevent you from rolling back to previous versions of your
11144 system, should you ever need to.
11146 @cindex roll-back, of the operating system
11147 Speaking of roll-back, each time you run @command{guix system
11148 reconfigure}, a new @dfn{generation} of the system is created---without
11149 modifying or deleting previous generations. Old system generations get
11150 an entry in the bootloader boot menu, allowing you to boot them in case
11151 something went wrong with the latest generation. Reassuring, no? The
11152 @command{guix system list-generations} command lists the system
11153 generations available on disk. It is also possible to roll back the
11154 system via the commands @command{guix system roll-back} and
11155 @command{guix system switch-generation}.
11157 Although the @command{guix system reconfigure} command will not modify
11158 previous generations, you must take care when the current generation is not
11159 the latest (e.g., after invoking @command{guix system roll-back}), since
11160 the operation might overwrite a later generation (@pxref{Invoking guix
11163 @unnumberedsubsec The Programming Interface
11165 At the Scheme level, the bulk of an @code{operating-system} declaration
11166 is instantiated with the following monadic procedure (@pxref{The Store
11169 @deffn {Monadic Procedure} operating-system-derivation os
11170 Return a derivation that builds @var{os}, an @code{operating-system}
11171 object (@pxref{Derivations}).
11173 The output of the derivation is a single directory that refers to all
11174 the packages, configuration files, and other supporting files needed to
11175 instantiate @var{os}.
11178 This procedure is provided by the @code{(gnu system)} module. Along
11179 with @code{(gnu services)} (@pxref{Services}), this module contains the
11180 guts of Guix System. Make sure to visit it!
11183 @node operating-system Reference
11184 @section @code{operating-system} Reference
11186 This section summarizes all the options available in
11187 @code{operating-system} declarations (@pxref{Using the Configuration
11190 @deftp {Data Type} operating-system
11191 This is the data type representing an operating system configuration.
11192 By that, we mean all the global system configuration, not per-user
11193 configuration (@pxref{Using the Configuration System}).
11196 @item @code{kernel} (default: @var{linux-libre})
11197 The package object of the operating system kernel to use@footnote{Currently
11198 only the Linux-libre kernel is supported. In the future, it will be
11199 possible to use the GNU@tie{}Hurd.}.
11201 @item @code{kernel-arguments} (default: @code{'("quiet")})
11202 List of strings or gexps representing additional arguments to pass on
11203 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
11205 @item @code{bootloader}
11206 The system bootloader configuration object. @xref{Bootloader Configuration}.
11209 This is the label (a string) as it appears in the bootloader's menu entry.
11210 The default label includes the kernel name and version.
11212 @item @code{keyboard-layout} (default: @code{#f})
11213 This field specifies the keyboard layout to use in the console. It can be
11214 either @code{#f}, in which case the default keyboard layout is used (usually
11215 US English), or a @code{<keyboard-layout>} record.
11217 This keyboard layout is in effect as soon as the kernel has booted. For
11218 instance, it is the keyboard layout in effect when you type a passphrase if
11219 your root file system is on a @code{luks-device-mapping} mapped device
11220 (@pxref{Mapped Devices}).
11223 This does @emph{not} specify the keyboard layout used by the bootloader, nor
11224 that used by the graphical display server. @xref{Bootloader Configuration},
11225 for information on how to specify the bootloader's keyboard layout. @xref{X
11226 Window}, for information on how to specify the keyboard layout used by the X
11230 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
11232 @cindex initial RAM disk
11233 The list of Linux kernel modules that need to be available in the
11234 initial RAM disk. @xref{Initial RAM Disk}.
11236 @item @code{initrd} (default: @code{base-initrd})
11237 A procedure that returns an initial RAM disk for the Linux
11238 kernel. This field is provided to support low-level customization and
11239 should rarely be needed for casual use. @xref{Initial RAM Disk}.
11241 @item @code{firmware} (default: @code{%base-firmware})
11243 List of firmware packages loadable by the operating system kernel.
11245 The default includes firmware needed for Atheros- and Broadcom-based
11246 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
11247 respectively). @xref{Hardware Considerations}, for more info on
11248 supported hardware.
11250 @item @code{host-name}
11253 @item @code{hosts-file}
11255 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
11256 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
11257 Reference Manual}). The default is a file with entries for
11258 @code{localhost} and @var{host-name}.
11260 @item @code{mapped-devices} (default: @code{'()})
11261 A list of mapped devices. @xref{Mapped Devices}.
11263 @item @code{file-systems}
11264 A list of file systems. @xref{File Systems}.
11266 @item @code{swap-devices} (default: @code{'()})
11267 @cindex swap devices
11268 A list of strings identifying devices or files to be used for ``swap
11269 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
11270 Manual}). For example, @code{'("/dev/sda3")} or @code{'("/swapfile")}.
11271 It is possible to specify a swap file in a file system on a mapped
11272 device, provided that the necessary device mapping and file system are
11273 also specified. @xref{Mapped Devices} and @ref{File Systems}.
11275 @item @code{users} (default: @code{%base-user-accounts})
11276 @itemx @code{groups} (default: @code{%base-groups})
11277 List of user accounts and groups. @xref{User Accounts}.
11279 If the @code{users} list lacks a user account with UID@tie{}0, a
11280 ``root'' account with UID@tie{}0 is automatically added.
11282 @item @code{skeletons} (default: @code{(default-skeletons)})
11283 A list target file name/file-like object tuples (@pxref{G-Expressions,
11284 file-like objects}). These are the skeleton files that will be added to
11285 the home directory of newly-created user accounts.
11287 For instance, a valid value may look like this:
11290 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
11291 (".guile" ,(plain-file "guile"
11292 "(use-modules (ice-9 readline))
11293 (activate-readline)")))
11296 @item @code{issue} (default: @code{%default-issue})
11297 A string denoting the contents of the @file{/etc/issue} file, which is
11298 displayed when users log in on a text console.
11300 @item @code{packages} (default: @code{%base-packages})
11301 The set of packages installed in the global profile, which is accessible
11302 at @file{/run/current-system/profile}.
11304 The default set includes core utilities and it is good practice to
11305 install non-core utilities in user profiles (@pxref{Invoking guix
11308 @item @code{timezone}
11309 A timezone identifying string---e.g., @code{"Europe/Paris"}.
11311 You can run the @command{tzselect} command to find out which timezone
11312 string corresponds to your region. Choosing an invalid timezone name
11313 causes @command{guix system} to fail.
11315 @item @code{locale} (default: @code{"en_US.utf8"})
11316 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
11317 Library Reference Manual}). @xref{Locales}, for more information.
11319 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
11320 The list of locale definitions to be compiled and that may be used at
11321 run time. @xref{Locales}.
11323 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
11324 The list of GNU@tie{}libc packages whose locale data and tools are used
11325 to build the locale definitions. @xref{Locales}, for compatibility
11326 considerations that justify this option.
11328 @item @code{name-service-switch} (default: @code{%default-nss})
11329 Configuration of the libc name service switch (NSS)---a
11330 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
11333 @item @code{services} (default: @code{%base-services})
11334 A list of service objects denoting system services. @xref{Services}.
11336 @cindex essential services
11337 @item @code{essential-services} (default: ...)
11338 The list of ``essential services''---i.e., things like instances of
11339 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
11340 Reference}), which are derived from the operating system definition itself.
11341 As a user you should @emph{never} need to touch this field.
11343 @item @code{pam-services} (default: @code{(base-pam-services)})
11345 @cindex pluggable authentication modules
11346 Linux @dfn{pluggable authentication module} (PAM) services.
11347 @c FIXME: Add xref to PAM services section.
11349 @item @code{setuid-programs} (default: @var{%setuid-programs})
11350 List of string-valued G-expressions denoting setuid programs.
11351 @xref{Setuid Programs}.
11353 @item @code{sudoers-file} (default: @var{%sudoers-specification})
11354 @cindex sudoers file
11355 The contents of the @file{/etc/sudoers} file as a file-like object
11356 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
11358 This file specifies which users can use the @command{sudo} command, what
11359 they are allowed to do, and what privileges they may gain. The default
11360 is that only @code{root} and members of the @code{wheel} group may use
11365 @deffn {Scheme Syntax} this-operating-system
11366 When used in the @emph{lexical scope} of an operating system field definition,
11367 this identifier resolves to the operating system being defined.
11369 The example below shows how to refer to the operating system being defined in
11370 the definition of the @code{label} field:
11373 (use-modules (gnu) (guix))
11377 (label (package-full-name
11378 (operating-system-kernel this-operating-system))))
11381 It is an error to refer to @code{this-operating-system} outside an operating
11388 @section File Systems
11390 The list of file systems to be mounted is specified in the
11391 @code{file-systems} field of the operating system declaration
11392 (@pxref{Using the Configuration System}). Each file system is declared
11393 using the @code{file-system} form, like this:
11397 (mount-point "/home")
11398 (device "/dev/sda3")
11402 As usual, some of the fields are mandatory---those shown in the example
11403 above---while others can be omitted. These are described below.
11405 @deftp {Data Type} file-system
11406 Objects of this type represent file systems to be mounted. They
11407 contain the following members:
11411 This is a string specifying the type of the file system---e.g.,
11414 @item @code{mount-point}
11415 This designates the place where the file system is to be mounted.
11417 @item @code{device}
11418 This names the ``source'' of the file system. It can be one of three
11419 things: a file system label, a file system UUID, or the name of a
11420 @file{/dev} node. Labels and UUIDs offer a way to refer to file
11421 systems without having to hard-code their actual device
11422 name@footnote{Note that, while it is tempting to use
11423 @file{/dev/disk/by-uuid} and similar device names to achieve the same
11424 result, this is not recommended: These special device nodes are created
11425 by the udev daemon and may be unavailable at the time the device is
11428 @findex file-system-label
11429 File system labels are created using the @code{file-system-label}
11430 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
11431 plain strings. Here's an example of a file system referred to by its
11432 label, as shown by the @command{e2label} command:
11436 (mount-point "/home")
11438 (device (file-system-label "my-home")))
11442 UUIDs are converted from their string representation (as shown by the
11443 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
11444 @code{uuid} form expects 16-byte UUIDs as defined in
11445 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
11446 form of UUID used by the ext2 family of file systems and others, but it
11447 is different from ``UUIDs'' found in FAT file systems, for instance.},
11452 (mount-point "/home")
11454 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
11457 When the source of a file system is a mapped device (@pxref{Mapped
11458 Devices}), its @code{device} field @emph{must} refer to the mapped
11459 device name---e.g., @file{"/dev/mapper/root-partition"}.
11460 This is required so that
11461 the system knows that mounting the file system depends on having the
11462 corresponding device mapping established.
11464 @item @code{flags} (default: @code{'()})
11465 This is a list of symbols denoting mount flags. Recognized flags
11466 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
11467 access to special files), @code{no-suid} (ignore setuid and setgid
11468 bits), @code{no-atime} (do not update file access times),
11469 @code{strict-atime} (update file access time), @code{lazy-time} (only
11470 update time on the in-memory version of the file inode), and
11471 @code{no-exec} (disallow program execution).
11472 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
11473 Manual}, for more information on these flags.
11475 @item @code{options} (default: @code{#f})
11476 This is either @code{#f}, or a string denoting mount options passed to the
11477 file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C Library
11478 Reference Manual}, for details and run @command{man 8 mount} for options for
11479 various file systems.
11481 @item @code{mount?} (default: @code{#t})
11482 This value indicates whether to automatically mount the file system when
11483 the system is brought up. When set to @code{#f}, the file system gets
11484 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
11485 is not automatically mounted.
11487 @item @code{needed-for-boot?} (default: @code{#f})
11488 This Boolean value indicates whether the file system is needed when
11489 booting. If that is true, then the file system is mounted when the
11490 initial RAM disk (initrd) is loaded. This is always the case, for
11491 instance, for the root file system.
11493 @item @code{check?} (default: @code{#t})
11494 This Boolean indicates whether the file system needs to be checked for
11495 errors before being mounted.
11497 @item @code{create-mount-point?} (default: @code{#f})
11498 When true, the mount point is created if it does not exist yet.
11500 @item @code{dependencies} (default: @code{'()})
11501 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
11502 representing file systems that must be mounted or mapped devices that
11503 must be opened before (and unmounted or closed after) this one.
11505 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
11506 a dependency of @file{/sys/fs/cgroup/cpu} and
11507 @file{/sys/fs/cgroup/memory}.
11509 Another example is a file system that depends on a mapped device, for
11510 example for an encrypted partition (@pxref{Mapped Devices}).
11514 The @code{(gnu system file-systems)} exports the following useful
11517 @defvr {Scheme Variable} %base-file-systems
11518 These are essential file systems that are required on normal systems,
11519 such as @var{%pseudo-terminal-file-system} and @var{%immutable-store} (see
11520 below.) Operating system declarations should always contain at least
11524 @defvr {Scheme Variable} %pseudo-terminal-file-system
11525 This is the file system to be mounted as @file{/dev/pts}. It supports
11526 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
11527 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
11528 Manual}). Pseudo-terminals are used by terminal emulators such as
11532 @defvr {Scheme Variable} %shared-memory-file-system
11533 This file system is mounted as @file{/dev/shm} and is used to support
11534 memory sharing across processes (@pxref{Memory-mapped I/O,
11535 @code{shm_open},, libc, The GNU C Library Reference Manual}).
11538 @defvr {Scheme Variable} %immutable-store
11539 This file system performs a read-only ``bind mount'' of
11540 @file{/gnu/store}, making it read-only for all the users including
11541 @code{root}. This prevents against accidental modification by software
11542 running as @code{root} or by system administrators.
11544 The daemon itself is still able to write to the store: it remounts it
11545 read-write in its own ``name space.''
11548 @defvr {Scheme Variable} %binary-format-file-system
11549 The @code{binfmt_misc} file system, which allows handling of arbitrary
11550 executable file types to be delegated to user space. This requires the
11551 @code{binfmt.ko} kernel module to be loaded.
11554 @defvr {Scheme Variable} %fuse-control-file-system
11555 The @code{fusectl} file system, which allows unprivileged users to mount
11556 and unmount user-space FUSE file systems. This requires the
11557 @code{fuse.ko} kernel module to be loaded.
11560 @node Mapped Devices
11561 @section Mapped Devices
11563 @cindex device mapping
11564 @cindex mapped devices
11565 The Linux kernel has a notion of @dfn{device mapping}: a block device,
11566 such as a hard disk partition, can be @dfn{mapped} into another device,
11567 usually in @code{/dev/mapper/},
11568 with additional processing over the data that flows through
11569 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
11570 concept of a ``mapped device'' and that of a file system: both boil down
11571 to @emph{translating} input/output operations made on a file to
11572 operations on its backing store. Thus, the Hurd implements mapped
11573 devices, like file systems, using the generic @dfn{translator} mechanism
11574 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
11575 typical example is encryption device mapping: all writes to the mapped
11576 device are encrypted, and all reads are deciphered, transparently.
11577 Guix extends this notion by considering any device or set of devices that
11578 are @dfn{transformed} in some way to create a new device; for instance,
11579 RAID devices are obtained by @dfn{assembling} several other devices, such
11580 as hard disks or partitions, into a new one that behaves as one partition.
11581 Other examples, not yet implemented, are LVM logical volumes.
11583 Mapped devices are declared using the @code{mapped-device} form,
11584 defined as follows; for examples, see below.
11586 @deftp {Data Type} mapped-device
11587 Objects of this type represent device mappings that will be made when
11588 the system boots up.
11592 This is either a string specifying the name of the block device to be mapped,
11593 such as @code{"/dev/sda3"}, or a list of such strings when several devices
11594 need to be assembled for creating a new one.
11597 This string specifies the name of the resulting mapped device. For
11598 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
11599 specifying @code{"my-partition"} leads to the creation of
11600 the @code{"/dev/mapper/my-partition"} device.
11601 For RAID devices of type @code{raid-device-mapping}, the full device name
11602 such as @code{"/dev/md0"} needs to be given.
11605 This must be a @code{mapped-device-kind} object, which specifies how
11606 @var{source} is mapped to @var{target}.
11610 @defvr {Scheme Variable} luks-device-mapping
11611 This defines LUKS block device encryption using the @command{cryptsetup}
11612 command from the package with the same name. It relies on the
11613 @code{dm-crypt} Linux kernel module.
11616 @defvr {Scheme Variable} raid-device-mapping
11617 This defines a RAID device, which is assembled using the @code{mdadm}
11618 command from the package with the same name. It requires a Linux kernel
11619 module for the appropriate RAID level to be loaded, such as @code{raid456}
11620 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
11623 @cindex disk encryption
11625 The following example specifies a mapping from @file{/dev/sda3} to
11626 @file{/dev/mapper/home} using LUKS---the
11627 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
11628 standard mechanism for disk encryption.
11629 The @file{/dev/mapper/home}
11630 device can then be used as the @code{device} of a @code{file-system}
11631 declaration (@pxref{File Systems}).
11635 (source "/dev/sda3")
11637 (type luks-device-mapping))
11640 Alternatively, to become independent of device numbering, one may obtain
11641 the LUKS UUID (@dfn{unique identifier}) of the source device by a
11645 cryptsetup luksUUID /dev/sda3
11648 and use it as follows:
11652 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
11654 (type luks-device-mapping))
11657 @cindex swap encryption
11658 It is also desirable to encrypt swap space, since swap space may contain
11659 sensitive data. One way to accomplish that is to use a swap file in a
11660 file system on a device mapped via LUKS encryption. In this way, the
11661 swap file is encrypted because the entire device is encrypted.
11662 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
11664 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
11665 may be declared as follows:
11669 (source (list "/dev/sda1" "/dev/sdb1"))
11670 (target "/dev/md0")
11671 (type raid-device-mapping))
11674 The @file{/dev/md0} device can then be used as the @code{device} of a
11675 @code{file-system} declaration (@pxref{File Systems}).
11676 Note that the RAID level need not be given; it is chosen during the
11677 initial creation and formatting of the RAID device and is determined
11678 automatically later.
11681 @node User Accounts
11682 @section User Accounts
11686 @cindex user accounts
11687 User accounts and groups are entirely managed through the
11688 @code{operating-system} declaration. They are specified with the
11689 @code{user-account} and @code{user-group} forms:
11695 (supplementary-groups '("wheel" ;allow use of sudo, etc.
11696 "audio" ;sound card
11697 "video" ;video devices such as webcams
11698 "cdrom")) ;the good ol' CD-ROM
11699 (comment "Bob's sister")
11700 (home-directory "/home/alice"))
11703 When booting or upon completion of @command{guix system reconfigure},
11704 the system ensures that only the user accounts and groups specified in
11705 the @code{operating-system} declaration exist, and with the specified
11706 properties. Thus, account or group creations or modifications made by
11707 directly invoking commands such as @command{useradd} are lost upon
11708 reconfiguration or reboot. This ensures that the system remains exactly
11711 @deftp {Data Type} user-account
11712 Objects of this type represent user accounts. The following members may
11717 The name of the user account.
11721 This is the name (a string) or identifier (a number) of the user group
11722 this account belongs to.
11724 @item @code{supplementary-groups} (default: @code{'()})
11725 Optionally, this can be defined as a list of group names that this
11726 account belongs to.
11728 @item @code{uid} (default: @code{#f})
11729 This is the user ID for this account (a number), or @code{#f}. In the
11730 latter case, a number is automatically chosen by the system when the
11731 account is created.
11733 @item @code{comment} (default: @code{""})
11734 A comment about the account, such as the account owner's full name.
11736 @item @code{home-directory}
11737 This is the name of the home directory for the account.
11739 @item @code{create-home-directory?} (default: @code{#t})
11740 Indicates whether the home directory of this account should be created
11741 if it does not exist yet.
11743 @item @code{shell} (default: Bash)
11744 This is a G-expression denoting the file name of a program to be used as
11745 the shell (@pxref{G-Expressions}).
11747 @item @code{system?} (default: @code{#f})
11748 This Boolean value indicates whether the account is a ``system''
11749 account. System accounts are sometimes treated specially; for instance,
11750 graphical login managers do not list them.
11752 @anchor{user-account-password}
11753 @cindex password, for user accounts
11754 @item @code{password} (default: @code{#f})
11755 You would normally leave this field to @code{#f}, initialize user
11756 passwords as @code{root} with the @command{passwd} command, and then let
11757 users change it with @command{passwd}. Passwords set with
11758 @command{passwd} are of course preserved across reboot and
11761 If you @emph{do} want to set an initial password for an account, then
11762 this field must contain the encrypted password, as a string. You can use the
11763 @code{crypt} procedure for this purpose:
11770 ;; Specify a SHA-512-hashed initial password.
11771 (password (crypt "InitialPassword!" "$6$abc")))
11775 The hash of this initial password will be available in a file in
11776 @file{/gnu/store}, readable by all the users, so this method must be used with
11780 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
11781 more information on password encryption, and @ref{Encryption,,, guile, GNU
11782 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
11788 User group declarations are even simpler:
11791 (user-group (name "students"))
11794 @deftp {Data Type} user-group
11795 This type is for, well, user groups. There are just a few fields:
11799 The name of the group.
11801 @item @code{id} (default: @code{#f})
11802 The group identifier (a number). If @code{#f}, a new number is
11803 automatically allocated when the group is created.
11805 @item @code{system?} (default: @code{#f})
11806 This Boolean value indicates whether the group is a ``system'' group.
11807 System groups have low numerical IDs.
11809 @item @code{password} (default: @code{#f})
11810 What, user groups can have a password? Well, apparently yes. Unless
11811 @code{#f}, this field specifies the password of the group.
11816 For convenience, a variable lists all the basic user groups one may
11819 @defvr {Scheme Variable} %base-groups
11820 This is the list of basic user groups that users and/or packages expect
11821 to be present on the system. This includes groups such as ``root'',
11822 ``wheel'', and ``users'', as well as groups used to control access to
11823 specific devices such as ``audio'', ``disk'', and ``cdrom''.
11826 @defvr {Scheme Variable} %base-user-accounts
11827 This is the list of basic system accounts that programs may expect to
11828 find on a GNU/Linux system, such as the ``nobody'' account.
11830 Note that the ``root'' account is not included here. It is a
11831 special-case and is automatically added whether or not it is specified.
11834 @node Keyboard Layout
11835 @section Keyboard Layout
11837 @cindex keyboard layout
11839 To specify what each key of your keyboard does, you need to tell the operating
11840 system what @dfn{keyboard layout} you want to use. The default, when nothing
11841 is specified, is the US English QWERTY layout for 105-key PC keyboards.
11842 However, German speakers will usually prefer the German QWERTZ layout, French
11843 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
11844 or bépo, and they might even want to further customize the effect of some of
11845 the keys. This section explains how to get that done.
11847 @cindex keyboard layout, definition
11848 There are three components that will want to know about your keyboard layout:
11852 The @emph{bootloader} may want to know what keyboard layout you want to use
11853 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
11854 you want, for instance, to make sure that you can type the passphrase of your
11855 encrypted root partition using the right layout.
11858 The @emph{operating system kernel}, Linux, will need that so that the console
11859 is properly configured (@pxref{operating-system Reference,
11860 @code{keyboard-layout}}).
11863 The @emph{graphical display server}, usually Xorg, also has its own idea of
11864 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
11867 Guix allows you to configure all three separately but, fortunately, it allows
11868 you to share the same keyboard layout for all three components.
11870 @cindex XKB, keyboard layouts
11871 Keyboard layouts are represented by records created by the
11872 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
11873 the X Keyboard extension (XKB), each layout has four attributes: a name (often
11874 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
11875 optional variant name, an optional keyboard model name, and a possibly empty
11876 list of additional options. In most cases the layout name is all you care
11877 about. Here are a few example:
11880 ;; The German QWERTZ layout. Here we assume a standard
11881 ;; "pc105" keyboard model.
11882 (keyboard-layout "de")
11884 ;; The bépo variant of the French layout.
11885 (keyboard-layout "fr" "bepo")
11887 ;; The Catalan layout.
11888 (keyboard-layout "es" "cat")
11890 ;; The Latin American Spanish layout. In addition, the
11891 ;; "Caps Lock" key is used as an additional "Ctrl" key,
11892 ;; and the "Menu" key is used as a "Compose" key to enter
11893 ;; accented letters.
11894 (keyboard-layout "latam"
11895 #:options '("ctrl:nocaps" "compose:menu"))
11897 ;; The Russian layout for a ThinkPad keyboard.
11898 (keyboard-layout "ru" #:model "thinkpad")
11900 ;; The "US international" layout, which is the US layout plus
11901 ;; dead keys to enter accented characters. This is for an
11902 ;; Apple MacBook keyboard.
11903 (keyboard-layout "us" "intl" #:model "macbook78")
11906 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
11907 for a complete list of supported layouts, variants, and models.
11909 @cindex keyboard layout, configuration
11910 Let's say you want your system to use the Turkish keyboard layout throughout
11911 your system---bootloader, console, and Xorg. Here's what your system
11912 configuration would look like:
11914 @findex set-xorg-configuration
11916 ;; Using the Turkish layout for the bootloader, the console,
11921 (keyboard-layout (keyboard-layout "tr")) ;for the console
11922 (bootloader (bootloader-configuration
11923 (bootloader grub-efi-bootloader)
11924 (target "/boot/efi")
11925 (keyboard-layout keyboard-layout))) ;for GRUB
11926 (services (cons (set-xorg-configuration
11927 (xorg-configuration ;for Xorg
11928 (keyboard-layout keyboard-layout)))
11929 %desktop-services)))
11932 In the example above, for GRUB and for Xorg, we just refer to the
11933 @code{keyboard-layout} field defined above, but we could just as well refer to
11934 a different layout. The @code{set-xorg-configuration} procedure communicates
11935 the desired Xorg configuration to the graphical log-in manager, by default
11938 We've discussed how to specify the @emph{default} keyboard layout of your
11939 system when it starts, but you can also adjust it at run time:
11943 If you're using GNOME, its settings panel has a ``Region & Language'' entry
11944 where you can select one or more keyboard layouts.
11947 Under Xorg, the @command{setxkbmap} command (from the same-named package)
11948 allows you to change the current layout. For example, this is how you would
11949 change the layout to US Dvorak:
11952 setxkbmap us dvorak
11956 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
11957 console. However, note that @code{loadkeys} does @emph{not} use the XKB
11958 keyboard layout categorization described above. The command below loads the
11959 French bépo layout:
11970 A @dfn{locale} defines cultural conventions for a particular language
11971 and region of the world (@pxref{Locales,,, libc, The GNU C Library
11972 Reference Manual}). Each locale has a name that typically has the form
11973 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
11974 @code{fr_LU.utf8} designates the locale for the French language, with
11975 cultural conventions from Luxembourg, and using the UTF-8 encoding.
11977 @cindex locale definition
11978 Usually, you will want to specify the default locale for the machine
11979 using the @code{locale} field of the @code{operating-system} declaration
11980 (@pxref{operating-system Reference, @code{locale}}).
11982 The selected locale is automatically added to the @dfn{locale
11983 definitions} known to the system if needed, with its codeset inferred
11984 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
11985 @code{UTF-8} codeset. Additional locale definitions can be specified in
11986 the @code{locale-definitions} slot of @code{operating-system}---this is
11987 useful, for instance, if the codeset could not be inferred from the
11988 locale name. The default set of locale definitions includes some widely
11989 used locales, but not all the available locales, in order to save space.
11991 For instance, to add the North Frisian locale for Germany, the value of
11995 (cons (locale-definition
11996 (name "fy_DE.utf8") (source "fy_DE"))
11997 %default-locale-definitions)
12000 Likewise, to save space, one might want @code{locale-definitions} to
12001 list only the locales that are actually used, as in:
12004 (list (locale-definition
12005 (name "ja_JP.eucjp") (source "ja_JP")
12006 (charset "EUC-JP")))
12010 The compiled locale definitions are available at
12011 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
12012 version, which is the default location where the GNU@tie{}libc provided
12013 by Guix looks for locale data. This can be overridden using the
12014 @code{LOCPATH} environment variable (@pxref{locales-and-locpath,
12015 @code{LOCPATH} and locale packages}).
12017 The @code{locale-definition} form is provided by the @code{(gnu system
12018 locale)} module. Details are given below.
12020 @deftp {Data Type} locale-definition
12021 This is the data type of a locale definition.
12026 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
12027 Reference Manual}, for more information on locale names.
12029 @item @code{source}
12030 The name of the source for that locale. This is typically the
12031 @code{@var{language}_@var{territory}} part of the locale name.
12033 @item @code{charset} (default: @code{"UTF-8"})
12034 The ``character set'' or ``code set'' for that locale,
12035 @uref{https://www.iana.org/assignments/character-sets, as defined by
12041 @defvr {Scheme Variable} %default-locale-definitions
12042 A list of commonly used UTF-8 locales, used as the default
12043 value of the @code{locale-definitions} field of @code{operating-system}
12046 @cindex locale name
12047 @cindex normalized codeset in locale names
12048 These locale definitions use the @dfn{normalized codeset} for the part
12049 that follows the dot in the name (@pxref{Using gettextized software,
12050 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
12051 instance it has @code{uk_UA.utf8} but @emph{not}, say,
12052 @code{uk_UA.UTF-8}.
12055 @subsection Locale Data Compatibility Considerations
12057 @cindex incompatibility, of locale data
12058 @code{operating-system} declarations provide a @code{locale-libcs} field
12059 to specify the GNU@tie{}libc packages that are used to compile locale
12060 declarations (@pxref{operating-system Reference}). ``Why would I
12061 care?'', you may ask. Well, it turns out that the binary format of
12062 locale data is occasionally incompatible from one libc version to
12065 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
12066 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
12067 For instance, a program linked against libc version 2.21 is unable to
12068 read locale data produced with libc 2.22; worse, that program
12069 @emph{aborts} instead of simply ignoring the incompatible locale
12070 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
12071 the incompatible locale data, which is already an improvement.}.
12072 Similarly, a program linked against libc 2.22 can read most, but not
12073 all, of the locale data from libc 2.21 (specifically, @code{LC_COLLATE}
12074 data is incompatible); thus calls to @code{setlocale} may fail, but
12075 programs will not abort.
12077 The ``problem'' with Guix is that users have a lot of freedom: They can
12078 choose whether and when to upgrade software in their profiles, and might
12079 be using a libc version different from the one the system administrator
12080 used to build the system-wide locale data.
12082 Fortunately, unprivileged users can also install their own locale data
12083 and define @var{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
12084 @code{GUIX_LOCPATH} and locale packages}).
12086 Still, it is best if the system-wide locale data at
12087 @file{/run/current-system/locale} is built for all the libc versions
12088 actually in use on the system, so that all the programs can access
12089 it---this is especially crucial on a multi-user system. To do that, the
12090 administrator can specify several libc packages in the
12091 @code{locale-libcs} field of @code{operating-system}:
12094 (use-package-modules base)
12098 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
12101 This example would lead to a system containing locale definitions for
12102 both libc 2.21 and the current version of libc in
12103 @file{/run/current-system/locale}.
12109 @cindex system services
12110 An important part of preparing an @code{operating-system} declaration is
12111 listing @dfn{system services} and their configuration (@pxref{Using the
12112 Configuration System}). System services are typically daemons launched
12113 when the system boots, or other actions needed at that time---e.g.,
12114 configuring network access.
12116 Guix has a broad definition of ``service'' (@pxref{Service
12117 Composition}), but many services are managed by the GNU@tie{}Shepherd
12118 (@pxref{Shepherd Services}). On a running system, the @command{herd}
12119 command allows you to list the available services, show their status,
12120 start and stop them, or do other specific operations (@pxref{Jump
12121 Start,,, shepherd, The GNU Shepherd Manual}). For example:
12127 The above command, run as @code{root}, lists the currently defined
12128 services. The @command{herd doc} command shows a synopsis of the given
12129 service and its associated actions:
12133 Run libc's name service cache daemon (nscd).
12135 # herd doc nscd action invalidate
12136 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
12139 The @command{start}, @command{stop}, and @command{restart} sub-commands
12140 have the effect you would expect. For instance, the commands below stop
12141 the nscd service and restart the Xorg display server:
12145 Service nscd has been stopped.
12146 # herd restart xorg-server
12147 Service xorg-server has been stopped.
12148 Service xorg-server has been started.
12151 The following sections document the available services, starting with
12152 the core services, that may be used in an @code{operating-system}
12156 * Base Services:: Essential system services.
12157 * Scheduled Job Execution:: The mcron service.
12158 * Log Rotation:: The rottlog service.
12159 * Networking Services:: Network setup, SSH daemon, etc.
12160 * X Window:: Graphical display.
12161 * Printing Services:: Local and remote printer support.
12162 * Desktop Services:: D-Bus and desktop services.
12163 * Sound Services:: ALSA and Pulseaudio services.
12164 * Database Services:: SQL databases, key-value stores, etc.
12165 * Mail Services:: IMAP, POP3, SMTP, and all that.
12166 * Messaging Services:: Messaging services.
12167 * Telephony Services:: Telephony services.
12168 * Monitoring Services:: Monitoring services.
12169 * Kerberos Services:: Kerberos services.
12170 * LDAP Services:: LDAP services.
12171 * Web Services:: Web servers.
12172 * Certificate Services:: TLS certificates via Let's Encrypt.
12173 * DNS Services:: DNS daemons.
12174 * VPN Services:: VPN daemons.
12175 * Network File System:: NFS related services.
12176 * Continuous Integration:: The Cuirass service.
12177 * Power Management Services:: Extending battery life.
12178 * Audio Services:: The MPD.
12179 * Virtualization Services:: Virtualization services.
12180 * Version Control Services:: Providing remote access to Git repositories.
12181 * Game Services:: Game servers.
12182 * PAM Mount Service:: Service to mount volumes when logging in.
12183 * Guix Services:: Services relating specifically to Guix.
12184 * Linux Services:: Services tied to the Linux kernel.
12185 * Miscellaneous Services:: Other services.
12188 @node Base Services
12189 @subsection Base Services
12191 The @code{(gnu services base)} module provides definitions for the basic
12192 services that one expects from the system. The services exported by
12193 this module are listed below.
12195 @defvr {Scheme Variable} %base-services
12196 This variable contains a list of basic services (@pxref{Service Types
12197 and Services}, for more information on service objects) one would
12198 expect from the system: a login service (mingetty) on each tty, syslogd,
12199 the libc name service cache daemon (nscd), the udev device manager, and
12202 This is the default value of the @code{services} field of
12203 @code{operating-system} declarations. Usually, when customizing a
12204 system, you will want to append services to @code{%base-services}, like
12208 (append (list (service avahi-service-type)
12209 (service openssh-service-type))
12214 @defvr {Scheme Variable} special-files-service-type
12215 This is the service that sets up ``special files'' such as
12216 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
12218 The value associated with @code{special-files-service-type} services
12219 must be a list of tuples where the first element is the ``special file''
12220 and the second element is its target. By default it is:
12222 @cindex @file{/bin/sh}
12223 @cindex @file{sh}, in @file{/bin}
12225 `(("/bin/sh" ,(file-append bash "/bin/sh")))
12228 @cindex @file{/usr/bin/env}
12229 @cindex @file{env}, in @file{/usr/bin}
12230 If you want to add, say, @code{/usr/bin/env} to your system, you can
12234 `(("/bin/sh" ,(file-append bash "/bin/sh"))
12235 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
12238 Since this is part of @code{%base-services}, you can use
12239 @code{modify-services} to customize the set of special files
12240 (@pxref{Service Reference, @code{modify-services}}). But the simple way
12241 to add a special file is @i{via} the @code{extra-special-file} procedure
12245 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
12246 Use @var{target} as the ``special file'' @var{file}.
12248 For example, adding the following lines to the @code{services} field of
12249 your operating system declaration leads to a @file{/usr/bin/env}
12253 (extra-special-file "/usr/bin/env"
12254 (file-append coreutils "/bin/env"))
12258 @deffn {Scheme Procedure} host-name-service @var{name}
12259 Return a service that sets the host name to @var{name}.
12262 @deffn {Scheme Procedure} login-service @var{config}
12263 Return a service to run login according to @var{config}, a
12264 @code{<login-configuration>} object, which specifies the message of the day,
12265 among other things.
12268 @deftp {Data Type} login-configuration
12269 This is the data type representing the configuration of login.
12274 @cindex message of the day
12275 A file-like object containing the ``message of the day''.
12277 @item @code{allow-empty-passwords?} (default: @code{#t})
12278 Allow empty passwords by default so that first-time users can log in when
12279 the 'root' account has just been created.
12284 @deffn {Scheme Procedure} mingetty-service @var{config}
12285 Return a service to run mingetty according to @var{config}, a
12286 @code{<mingetty-configuration>} object, which specifies the tty to run, among
12290 @deftp {Data Type} mingetty-configuration
12291 This is the data type representing the configuration of Mingetty, which
12292 provides the default implementation of virtual console log-in.
12297 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
12299 @item @code{auto-login} (default: @code{#f})
12300 When true, this field must be a string denoting the user name under
12301 which the system automatically logs in. When it is @code{#f}, a
12302 user name and password must be entered to log in.
12304 @item @code{login-program} (default: @code{#f})
12305 This must be either @code{#f}, in which case the default log-in program
12306 is used (@command{login} from the Shadow tool suite), or a gexp denoting
12307 the name of the log-in program.
12309 @item @code{login-pause?} (default: @code{#f})
12310 When set to @code{#t} in conjunction with @var{auto-login}, the user
12311 will have to press a key before the log-in shell is launched.
12313 @item @code{mingetty} (default: @var{mingetty})
12314 The Mingetty package to use.
12319 @deffn {Scheme Procedure} agetty-service @var{config}
12320 Return a service to run agetty according to @var{config}, an
12321 @code{<agetty-configuration>} object, which specifies the tty to run,
12322 among other things.
12325 @deftp {Data Type} agetty-configuration
12326 This is the data type representing the configuration of agetty, which
12327 implements virtual and serial console log-in. See the @code{agetty(8)}
12328 man page for more information.
12333 The name of the console this agetty runs on, as a string---e.g.,
12334 @code{"ttyS0"}. This argument is optional, it will default to
12335 a reasonable default serial port used by the kernel Linux.
12337 For this, if there is a value for an option @code{agetty.tty} in the kernel
12338 command line, agetty will extract the device name of the serial port
12339 from it and use that.
12341 If not and if there is a value for an option @code{console} with a tty in
12342 the Linux command line, agetty will extract the device name of the
12343 serial port from it and use that.
12345 In both cases, agetty will leave the other serial device settings
12346 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
12349 @item @code{baud-rate} (default: @code{#f})
12350 A string containing a comma-separated list of one or more baud rates, in
12353 @item @code{term} (default: @code{#f})
12354 A string containing the value used for the @code{TERM} environment
12357 @item @code{eight-bits?} (default: @code{#f})
12358 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
12361 @item @code{auto-login} (default: @code{#f})
12362 When passed a login name, as a string, the specified user will be logged
12363 in automatically without prompting for their login name or password.
12365 @item @code{no-reset?} (default: @code{#f})
12366 When @code{#t}, don't reset terminal cflags (control modes).
12368 @item @code{host} (default: @code{#f})
12369 This accepts a string containing the "login_host", which will be written
12370 into the @file{/var/run/utmpx} file.
12372 @item @code{remote?} (default: @code{#f})
12373 When set to @code{#t} in conjunction with @var{host}, this will add an
12374 @code{-r} fakehost option to the command line of the login program
12375 specified in @var{login-program}.
12377 @item @code{flow-control?} (default: @code{#f})
12378 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
12380 @item @code{no-issue?} (default: @code{#f})
12381 When set to @code{#t}, the contents of the @file{/etc/issue} file will
12382 not be displayed before presenting the login prompt.
12384 @item @code{init-string} (default: @code{#f})
12385 This accepts a string that will be sent to the tty or modem before
12386 sending anything else. It can be used to initialize a modem.
12388 @item @code{no-clear?} (default: @code{#f})
12389 When set to @code{#t}, agetty will not clear the screen before showing
12392 @item @code{login-program} (default: (file-append shadow "/bin/login"))
12393 This must be either a gexp denoting the name of a log-in program, or
12394 unset, in which case the default value is the @command{login} from the
12397 @item @code{local-line} (default: @code{#f})
12398 Control the CLOCAL line flag. This accepts one of three symbols as
12399 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
12400 the default value chosen by agetty is @code{'auto}.
12402 @item @code{extract-baud?} (default: @code{#f})
12403 When set to @code{#t}, instruct agetty to try to extract the baud rate
12404 from the status messages produced by certain types of modems.
12406 @item @code{skip-login?} (default: @code{#f})
12407 When set to @code{#t}, do not prompt the user for a login name. This
12408 can be used with @var{login-program} field to use non-standard login
12411 @item @code{no-newline?} (default: @code{#f})
12412 When set to @code{#t}, do not print a newline before printing the
12413 @file{/etc/issue} file.
12415 @c Is this dangerous only when used with login-program, or always?
12416 @item @code{login-options} (default: @code{#f})
12417 This option accepts a string containing options that are passed to the
12418 login program. When used with the @var{login-program}, be aware that a
12419 malicious user could try to enter a login name containing embedded
12420 options that could be parsed by the login program.
12422 @item @code{login-pause} (default: @code{#f})
12423 When set to @code{#t}, wait for any key before showing the login prompt.
12424 This can be used in conjunction with @var{auto-login} to save memory by
12425 lazily spawning shells.
12427 @item @code{chroot} (default: @code{#f})
12428 Change root to the specified directory. This option accepts a directory
12431 @item @code{hangup?} (default: @code{#f})
12432 Use the Linux system call @code{vhangup} to do a virtual hangup of the
12433 specified terminal.
12435 @item @code{keep-baud?} (default: @code{#f})
12436 When set to @code{#t}, try to keep the existing baud rate. The baud
12437 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
12440 @item @code{timeout} (default: @code{#f})
12441 When set to an integer value, terminate if no user name could be read
12442 within @var{timeout} seconds.
12444 @item @code{detect-case?} (default: @code{#f})
12445 When set to @code{#t}, turn on support for detecting an uppercase-only
12446 terminal. This setting will detect a login name containing only
12447 uppercase letters as indicating an uppercase-only terminal and turn on
12448 some upper-to-lower case conversions. Note that this will not support
12449 Unicode characters.
12451 @item @code{wait-cr?} (default: @code{#f})
12452 When set to @code{#t}, wait for the user or modem to send a
12453 carriage-return or linefeed character before displaying
12454 @file{/etc/issue} or login prompt. This is typically used with the
12455 @var{init-string} option.
12457 @item @code{no-hints?} (default: @code{#f})
12458 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
12461 @item @code{no-hostname?} (default: @code{#f})
12462 By default, the hostname is printed. When this option is set to
12463 @code{#t}, no hostname will be shown at all.
12465 @item @code{long-hostname?} (default: @code{#f})
12466 By default, the hostname is only printed until the first dot. When this
12467 option is set to @code{#t}, the fully qualified hostname by
12468 @code{gethostname} or @code{getaddrinfo} is shown.
12470 @item @code{erase-characters} (default: @code{#f})
12471 This option accepts a string of additional characters that should be
12472 interpreted as backspace when the user types their login name.
12474 @item @code{kill-characters} (default: @code{#f})
12475 This option accepts a string that should be interpreted to mean "ignore
12476 all previous characters" (also called a "kill" character) when the user
12477 types their login name.
12479 @item @code{chdir} (default: @code{#f})
12480 This option accepts, as a string, a directory path that will be changed
12483 @item @code{delay} (default: @code{#f})
12484 This options accepts, as an integer, the number of seconds to sleep
12485 before opening the tty and displaying the login prompt.
12487 @item @code{nice} (default: @code{#f})
12488 This option accepts, as an integer, the nice value with which to run the
12489 @command{login} program.
12491 @item @code{extra-options} (default: @code{'()})
12492 This option provides an "escape hatch" for the user to provide arbitrary
12493 command-line arguments to @command{agetty} as a list of strings.
12498 @deffn {Scheme Procedure} kmscon-service-type @var{config}
12499 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
12500 according to @var{config}, a @code{<kmscon-configuration>} object, which
12501 specifies the tty to run, among other things.
12504 @deftp {Data Type} kmscon-configuration
12505 This is the data type representing the configuration of Kmscon, which
12506 implements virtual console log-in.
12510 @item @code{virtual-terminal}
12511 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
12513 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
12514 A gexp denoting the name of the log-in program. The default log-in program is
12515 @command{login} from the Shadow tool suite.
12517 @item @code{login-arguments} (default: @code{'("-p")})
12518 A list of arguments to pass to @command{login}.
12520 @item @code{auto-login} (default: @code{#f})
12521 When passed a login name, as a string, the specified user will be logged
12522 in automatically without prompting for their login name or password.
12524 @item @code{hardware-acceleration?} (default: #f)
12525 Whether to use hardware acceleration.
12527 @item @code{kmscon} (default: @var{kmscon})
12528 The Kmscon package to use.
12533 @cindex name service cache daemon
12535 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
12536 [#:name-services '()]
12537 Return a service that runs the libc name service cache daemon (nscd) with the
12538 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
12539 Service Switch}, for an example.
12541 For convenience, the Shepherd service for nscd provides the following actions:
12545 @cindex cache invalidation, nscd
12546 @cindex nscd, cache invalidation
12547 This invalidate the given cache. For instance, running:
12550 herd invalidate nscd hosts
12554 invalidates the host name lookup cache of nscd.
12557 Running @command{herd statistics nscd} displays information about nscd usage
12563 @defvr {Scheme Variable} %nscd-default-configuration
12564 This is the default @code{<nscd-configuration>} value (see below) used
12565 by @code{nscd-service}. It uses the caches defined by
12566 @var{%nscd-default-caches}; see below.
12569 @deftp {Data Type} nscd-configuration
12570 This is the data type representing the name service cache daemon (nscd)
12575 @item @code{name-services} (default: @code{'()})
12576 List of packages denoting @dfn{name services} that must be visible to
12577 the nscd---e.g., @code{(list @var{nss-mdns})}.
12579 @item @code{glibc} (default: @var{glibc})
12580 Package object denoting the GNU C Library providing the @command{nscd}
12583 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
12584 Name of the nscd log file. This is where debugging output goes when
12585 @code{debug-level} is strictly positive.
12587 @item @code{debug-level} (default: @code{0})
12588 Integer denoting the debugging levels. Higher numbers mean that more
12589 debugging output is logged.
12591 @item @code{caches} (default: @var{%nscd-default-caches})
12592 List of @code{<nscd-cache>} objects denoting things to be cached; see
12598 @deftp {Data Type} nscd-cache
12599 Data type representing a cache database of nscd and its parameters.
12603 @item @code{database}
12604 This is a symbol representing the name of the database to be cached.
12605 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
12606 @code{services}, which designate the corresponding NSS database
12607 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
12609 @item @code{positive-time-to-live}
12610 @itemx @code{negative-time-to-live} (default: @code{20})
12611 A number representing the number of seconds during which a positive or
12612 negative lookup result remains in cache.
12614 @item @code{check-files?} (default: @code{#t})
12615 Whether to check for updates of the files corresponding to
12618 For instance, when @var{database} is @code{hosts}, setting this flag
12619 instructs nscd to check for updates in @file{/etc/hosts} and to take
12622 @item @code{persistent?} (default: @code{#t})
12623 Whether the cache should be stored persistently on disk.
12625 @item @code{shared?} (default: @code{#t})
12626 Whether the cache should be shared among users.
12628 @item @code{max-database-size} (default: 32@tie{}MiB)
12629 Maximum size in bytes of the database cache.
12631 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
12632 @c settings, so leave them out.
12637 @defvr {Scheme Variable} %nscd-default-caches
12638 List of @code{<nscd-cache>} objects used by default by
12639 @code{nscd-configuration} (see above).
12641 It enables persistent and aggressive caching of service and host name
12642 lookups. The latter provides better host name lookup performance,
12643 resilience in the face of unreliable name servers, and also better
12644 privacy---often the result of host name lookups is in local cache, so
12645 external name servers do not even need to be queried.
12648 @anchor{syslog-configuration-type}
12651 @deftp {Data Type} syslog-configuration
12652 This data type represents the configuration of the syslog daemon.
12655 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
12656 The syslog daemon to use.
12658 @item @code{config-file} (default: @code{%default-syslog.conf})
12659 The syslog configuration file to use.
12664 @anchor{syslog-service}
12666 @deffn {Scheme Procedure} syslog-service @var{config}
12667 Return a service that runs a syslog daemon according to @var{config}.
12669 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
12670 information on the configuration file syntax.
12673 @defvr {Scheme Variable} guix-service-type
12674 This is the type of the service that runs the build daemon,
12675 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
12676 @code{guix-configuration} record as described below.
12679 @anchor{guix-configuration-type}
12680 @deftp {Data Type} guix-configuration
12681 This data type represents the configuration of the Guix build daemon.
12682 @xref{Invoking guix-daemon}, for more information.
12685 @item @code{guix} (default: @var{guix})
12686 The Guix package to use.
12688 @item @code{build-group} (default: @code{"guixbuild"})
12689 Name of the group for build user accounts.
12691 @item @code{build-accounts} (default: @code{10})
12692 Number of build user accounts to create.
12694 @item @code{authorize-key?} (default: @code{#t})
12695 @cindex substitutes, authorization thereof
12696 Whether to authorize the substitute keys listed in
12697 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
12698 (@pxref{Substitutes}).
12700 @vindex %default-authorized-guix-keys
12701 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
12702 The list of authorized key files for archive imports, as a list of
12703 string-valued gexps (@pxref{Invoking guix archive}). By default, it
12704 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
12706 @item @code{use-substitutes?} (default: @code{#t})
12707 Whether to use substitutes.
12709 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
12710 The list of URLs where to look for substitutes by default.
12712 @item @code{max-silent-time} (default: @code{0})
12713 @itemx @code{timeout} (default: @code{0})
12714 The number of seconds of silence and the number of seconds of activity,
12715 respectively, after which a build process times out. A value of zero
12716 disables the timeout.
12718 @item @code{log-compression} (default: @code{'bzip2})
12719 The type of compression used for build logs---one of @code{gzip},
12720 @code{bzip2}, or @code{none}.
12722 @item @code{extra-options} (default: @code{'()})
12723 List of extra command-line options for @command{guix-daemon}.
12725 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
12726 File where @command{guix-daemon}'s standard output and standard error
12729 @item @code{http-proxy} (default: @code{#f})
12730 The HTTP proxy used for downloading fixed-output derivations and
12733 @item @code{tmpdir} (default: @code{#f})
12734 A directory path where the @command{guix-daemon} will perform builds.
12739 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
12740 Run @var{udev}, which populates the @file{/dev} directory dynamically.
12741 udev rules can be provided as a list of files through the @var{rules}
12742 variable. The procedures @code{udev-rule} and @code{file->udev-rule} from
12743 @code{(gnu services base)} simplify the creation of such rule files.
12746 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
12747 Return a udev-rule file named @var{file-name} containing the rules
12748 defined by the @var{contents} literal.
12750 In the following example, a rule for a USB device is defined to be
12751 stored in the file @file{90-usb-thing.rules}. The rule runs a script
12752 upon detecting a USB device with a given product identifier.
12755 (define %example-udev-rule
12757 "90-usb-thing.rules"
12758 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
12759 "ATTR@{product@}==\"Example\", "
12760 "RUN+=\"/path/to/script\"")))
12763 The @command{herd rules udev} command, as root, returns the name of the
12764 directory containing all the active udev rules.
12767 Here we show how the default @var{udev-service} can be extended with it.
12773 (modify-services %desktop-services
12774 (udev-service-type config =>
12775 (udev-configuration (inherit config)
12776 (rules (append (udev-configuration-rules config)
12777 (list %example-udev-rule))))))))
12780 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
12781 Return a udev file named @var{file-name} containing the rules defined
12782 within @var{file}, a file-like object.
12784 The following example showcases how we can use an existing rule file.
12787 (use-modules (guix download) ;for url-fetch
12788 (guix packages) ;for origin
12791 (define %android-udev-rules
12793 "51-android-udev.rules"
12794 (let ((version "20170910"))
12797 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
12798 "android-udev-rules/" version "/51-android.rules"))
12800 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
12804 Additionally, Guix package definitions can be included in @var{rules} in
12805 order to extend the udev rules with the definitions found under their
12806 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
12807 @var{file->udev-rule} example, we could have used the
12808 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
12809 packages android)} module.
12811 The following example shows how to use the @var{android-udev-rules}
12812 package so that the Android tool @command{adb} can detect devices
12813 without root privileges. It also details how to create the
12814 @code{adbusers} group, which is required for the proper functioning of
12815 the rules defined within the @var{android-udev-rules} package. To
12816 create such a group, we must define it both as part of the
12817 @var{supplementary-groups} of our @var{user-account} declaration, as
12818 well as in the @var{groups} field of the @var{operating-system} record.
12821 (use-modules (gnu packages android) ;for android-udev-rules
12822 (gnu system shadow) ;for user-group
12827 (users (cons (user-acount
12829 (supplementary-groups
12830 '("adbusers" ;for adb
12831 "wheel" "netdev" "audio" "video")))))
12833 (groups (cons (user-group (system? #t) (name "adbusers"))
12839 (modify-services %desktop-services
12842 (udev-configuration (inherit config)
12843 (rules (cons android-udev-rules
12844 (udev-configuration-rules config))))))))
12847 @defvr {Scheme Variable} urandom-seed-service-type
12848 Save some entropy in @var{%random-seed-file} to seed @file{/dev/urandom}
12849 when rebooting. It also tries to seed @file{/dev/urandom} from
12850 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
12854 @defvr {Scheme Variable} %random-seed-file
12855 This is the name of the file where some random bytes are saved by
12856 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
12857 It defaults to @file{/var/lib/random-seed}.
12862 @defvr {Scheme Variable} gpm-service-type
12863 This is the type of the service that runs GPM, the @dfn{general-purpose
12864 mouse daemon}, which provides mouse support to the Linux console. GPM
12865 allows users to use the mouse in the console, notably to select, copy,
12868 The value for services of this type must be a @code{gpm-configuration}
12869 (see below). This service is not part of @code{%base-services}.
12872 @deftp {Data Type} gpm-configuration
12873 Data type representing the configuration of GPM.
12876 @item @code{options} (default: @code{%default-gpm-options})
12877 Command-line options passed to @command{gpm}. The default set of
12878 options instruct @command{gpm} to listen to mouse events on
12879 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
12882 @item @code{gpm} (default: @code{gpm})
12883 The GPM package to use.
12888 @anchor{guix-publish-service-type}
12889 @deffn {Scheme Variable} guix-publish-service-type
12890 This is the service type for @command{guix publish} (@pxref{Invoking
12891 guix publish}). Its value must be a @code{guix-publish-configuration}
12892 object, as described below.
12894 This assumes that @file{/etc/guix} already contains a signing key pair as
12895 created by @command{guix archive --generate-key} (@pxref{Invoking guix
12896 archive}). If that is not the case, the service will fail to start.
12899 @deftp {Data Type} guix-publish-configuration
12900 Data type representing the configuration of the @code{guix publish}
12904 @item @code{guix} (default: @code{guix})
12905 The Guix package to use.
12907 @item @code{port} (default: @code{80})
12908 The TCP port to listen for connections.
12910 @item @code{host} (default: @code{"localhost"})
12911 The host (and thus, network interface) to listen to. Use
12912 @code{"0.0.0.0"} to listen on all the network interfaces.
12914 @item @code{compression} (default: @code{'(("gzip" 3))})
12915 This is a list of compression method/level tuple used when compressing
12916 substitutes. For example, to compress all substitutes with @emph{both} lzip
12917 at level 7 and gzip at level 9, write:
12920 '(("lzip" 7) ("gzip" 9))
12923 Level 9 achieves the best compression ratio at the expense of increased CPU
12924 usage, whereas level 1 achieves fast compression.
12926 An empty list disables compression altogether.
12928 @item @code{nar-path} (default: @code{"nar"})
12929 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
12930 publish, @code{--nar-path}}, for details.
12932 @item @code{cache} (default: @code{#f})
12933 When it is @code{#f}, disable caching and instead generate archives on
12934 demand. Otherwise, this should be the name of a directory---e.g.,
12935 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
12936 archives and meta-data ready to be sent. @xref{Invoking guix publish,
12937 @option{--cache}}, for more information on the tradeoffs involved.
12939 @item @code{workers} (default: @code{#f})
12940 When it is an integer, this is the number of worker threads used for
12941 caching; when @code{#f}, the number of processors is used.
12942 @xref{Invoking guix publish, @option{--workers}}, for more information.
12944 @item @code{ttl} (default: @code{#f})
12945 When it is an integer, this denotes the @dfn{time-to-live} in seconds
12946 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
12947 for more information.
12951 @anchor{rngd-service}
12952 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
12953 [#:device "/dev/hwrng"]
12954 Return a service that runs the @command{rngd} program from @var{rng-tools}
12955 to add @var{device} to the kernel's entropy pool. The service will fail if
12956 @var{device} does not exist.
12959 @anchor{pam-limits-service}
12960 @cindex session limits
12965 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
12967 Return a service that installs a configuration file for the
12968 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
12969 @code{pam_limits} module}. The procedure optionally takes a list of
12970 @code{pam-limits-entry} values, which can be used to specify
12971 @code{ulimit} limits and nice priority limits to user sessions.
12973 The following limits definition sets two hard and soft limits for all
12974 login sessions of users in the @code{realtime} group:
12977 (pam-limits-service
12979 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
12980 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
12983 The first entry increases the maximum realtime priority for
12984 non-privileged processes; the second entry lifts any restriction of the
12985 maximum address space that can be locked in memory. These settings are
12986 commonly used for real-time audio systems.
12989 @node Scheduled Job Execution
12990 @subsection Scheduled Job Execution
12994 @cindex scheduling jobs
12995 The @code{(gnu services mcron)} module provides an interface to
12996 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
12997 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
12998 Unix @command{cron} daemon; the main difference is that it is
12999 implemented in Guile Scheme, which provides a lot of flexibility when
13000 specifying the scheduling of jobs and their actions.
13002 The example below defines an operating system that runs the
13003 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
13004 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
13005 well as the @command{mkid} command on behalf of an unprivileged user
13006 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
13007 gexps to introduce job definitions that are passed to mcron
13008 (@pxref{G-Expressions}).
13011 (use-modules (guix) (gnu) (gnu services mcron))
13012 (use-package-modules base idutils)
13014 (define updatedb-job
13015 ;; Run 'updatedb' at 3AM every day. Here we write the
13016 ;; job's action as a Scheme procedure.
13017 #~(job '(next-hour '(3))
13019 (execl (string-append #$findutils "/bin/updatedb")
13021 "--prunepaths=/tmp /var/tmp /gnu/store"))))
13023 (define garbage-collector-job
13024 ;; Collect garbage 5 minutes after midnight every day.
13025 ;; The job's action is a shell command.
13026 #~(job "5 0 * * *" ;Vixie cron syntax
13029 (define idutils-job
13030 ;; Update the index database as user "charlie" at 12:15PM
13031 ;; and 19:15PM. This runs from the user's home directory.
13032 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
13033 (string-append #$idutils "/bin/mkid src")
13038 (services (cons (service mcron-service-type
13039 (mcron-configuration
13040 (jobs (list garbage-collector-job
13046 For more complex jobs defined in Scheme where you need control over the top
13047 level, for instance to introduce a @code{use-modules} form, you can move your
13048 code to a separate program using the @code{program-file} procedure of the
13049 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
13053 (define %battery-alert-job
13054 ;; Beep when the battery percentage falls below %MIN-LEVEL.
13056 '(next-minute (range 0 60 1))
13058 "battery-alert.scm"
13059 (with-imported-modules (source-module-closure
13060 '((guix build utils)))
13062 (define %min-level 20)
13063 (use-modules (guix build utils)
13066 (ice-9 textual-ports)
13068 (setenv "LC_ALL" "C") ;ensure English output
13069 (and-let* ((input-pipe (open-pipe*
13071 #$(file-append acpi "/bin/acpi")))
13072 (output (get-string-all input-pipe))
13073 (m (string-match "Discharging, ([0-9]+)%" output))
13074 (level (string->number (match:substring m 1)))
13075 ((< level %min-level)))
13076 (format #t "warning: Battery level is low (~a%)~%" level)
13077 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
13080 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
13081 for more information on mcron job specifications. Below is the
13082 reference of the mcron service.
13084 On a running system, you can use the @code{schedule} action of the service to
13085 visualize the mcron jobs that will be executed next:
13088 # herd schedule mcron
13092 The example above lists the next five tasks that will be executed, but you can
13093 also specify the number of tasks to display:
13096 # herd schedule mcron 10
13099 @defvr {Scheme Variable} mcron-service-type
13100 This is the type of the @code{mcron} service, whose value is an
13101 @code{mcron-configuration} object.
13103 This service type can be the target of a service extension that provides
13104 it additional job specifications (@pxref{Service Composition}). In
13105 other words, it is possible to define services that provide additional
13109 @deftp {Data Type} mcron-configuration
13110 Data type representing the configuration of mcron.
13113 @item @code{mcron} (default: @var{mcron})
13114 The mcron package to use.
13117 This is a list of gexps (@pxref{G-Expressions}), where each gexp
13118 corresponds to an mcron job specification (@pxref{Syntax, mcron job
13119 specifications,, mcron, GNU@tie{}mcron}).
13125 @subsection Log Rotation
13128 @cindex log rotation
13130 Log files such as those found in @file{/var/log} tend to grow endlessly,
13131 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
13132 their contents in separate files, possibly compressed. The @code{(gnu
13133 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
13134 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
13136 The example below defines an operating system that provides log rotation
13137 with the default settings, for commonly encountered log files.
13140 (use-modules (guix) (gnu))
13141 (use-service-modules admin mcron)
13142 (use-package-modules base idutils)
13146 (services (cons (service rottlog-service-type)
13150 @defvr {Scheme Variable} rottlog-service-type
13151 This is the type of the Rottlog service, whose value is a
13152 @code{rottlog-configuration} object.
13154 Other services can extend this one with new @code{log-rotation} objects
13155 (see below), thereby augmenting the set of files to be rotated.
13157 This service type can define mcron jobs (@pxref{Scheduled Job
13158 Execution}) to run the rottlog service.
13161 @deftp {Data Type} rottlog-configuration
13162 Data type representing the configuration of rottlog.
13165 @item @code{rottlog} (default: @code{rottlog})
13166 The Rottlog package to use.
13168 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
13169 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
13170 rottlog, GNU Rot[t]log Manual}).
13172 @item @code{rotations} (default: @code{%default-rotations})
13173 A list of @code{log-rotation} objects as defined below.
13176 This is a list of gexps where each gexp corresponds to an mcron job
13177 specification (@pxref{Scheduled Job Execution}).
13181 @deftp {Data Type} log-rotation
13182 Data type representing the rotation of a group of log files.
13184 Taking an example from the Rottlog manual (@pxref{Period Related File
13185 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
13191 (files '("/var/log/apache/*"))
13192 (options '("storedir apache-archives"
13198 The list of fields is as follows:
13201 @item @code{frequency} (default: @code{'weekly})
13202 The log rotation frequency, a symbol.
13205 The list of files or file glob patterns to rotate.
13207 @item @code{options} (default: @code{'()})
13208 The list of rottlog options for this rotation (@pxref{Configuration
13209 parameters,,, rottlog, GNU Rot[t]lg Manual}).
13211 @item @code{post-rotate} (default: @code{#f})
13212 Either @code{#f} or a gexp to execute once the rotation has completed.
13216 @defvr {Scheme Variable} %default-rotations
13217 Specifies weekly rotation of @var{%rotated-files} and of
13218 @file{/var/log/guix-daemon.log}.
13221 @defvr {Scheme Variable} %rotated-files
13222 The list of syslog-controlled files to be rotated. By default it is:
13223 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
13224 "/var/log/maillog")}.
13227 @node Networking Services
13228 @subsection Networking Services
13230 The @code{(gnu services networking)} module provides services to configure
13231 the network interface.
13233 @cindex DHCP, networking service
13234 @defvr {Scheme Variable} dhcp-client-service-type
13235 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
13236 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
13237 is the DHCP client package to use, @code{isc-dhcp} by default.
13240 @deffn {Scheme Procedure} dhcpd-service-type
13241 This type defines a service that runs a DHCP daemon. To create a
13242 service of this type, you must supply a @code{<dhcpd-configuration>}.
13246 (service dhcpd-service-type
13247 (dhcpd-configuration
13248 (config-file (local-file "my-dhcpd.conf"))
13249 (interfaces '("enp0s25"))))
13253 @deftp {Data Type} dhcpd-configuration
13255 @item @code{package} (default: @code{isc-dhcp})
13256 The package that provides the DHCP daemon. This package is expected to
13257 provide the daemon at @file{sbin/dhcpd} relative to its output
13258 directory. The default package is the
13259 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
13260 @item @code{config-file} (default: @code{#f})
13261 The configuration file to use. This is required. It will be passed to
13262 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
13263 object (@pxref{G-Expressions, file-like objects}). See @code{man
13264 dhcpd.conf} for details on the configuration file syntax.
13265 @item @code{version} (default: @code{"4"})
13266 The DHCP version to use. The ISC DHCP server supports the values ``4'',
13267 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
13268 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
13270 @item @code{run-directory} (default: @code{"/run/dhcpd"})
13271 The run directory to use. At service activation time, this directory
13272 will be created if it does not exist.
13273 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
13274 The PID file to use. This corresponds to the @code{-pf} option of
13275 @code{dhcpd}. See @code{man dhcpd} for details.
13276 @item @code{interfaces} (default: @code{'()})
13277 The names of the network interfaces on which dhcpd should listen for
13278 broadcasts. If this list is not empty, then its elements (which must be
13279 strings) will be appended to the @code{dhcpd} invocation when starting
13280 the daemon. It may not be necessary to explicitly specify any
13281 interfaces here; see @code{man dhcpd} for details.
13285 @defvr {Scheme Variable} static-networking-service-type
13286 This is the type for statically-configured network interfaces.
13287 @c TODO Document <static-networking> data structures.
13290 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
13291 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
13292 [#:requirement @code{'(udev)}]
13293 Return a service that starts @var{interface} with address @var{ip}. If
13294 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
13295 it must be a string specifying the default network gateway. @var{requirement}
13296 can be used to declare a dependency on another service before configuring the
13299 This procedure can be called several times, one for each network
13300 interface of interest. Behind the scenes what it does is extend
13301 @code{static-networking-service-type} with additional network interfaces
13307 (static-networking-service "eno1" "192.168.1.82"
13308 #:gateway "192.168.1.2"
13309 #:name-servers '("192.168.1.2"))
13316 @cindex network management
13317 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
13318 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
13319 management daemon that aims to simplify wired and wireless networking.
13321 This service adds the @var{wicd} package to the global profile, providing
13322 several commands to interact with the daemon and configure networking:
13323 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
13324 and @command{wicd-curses} user interfaces.
13327 @cindex ModemManager
13329 @defvr {Scheme Variable} modem-manager-service-type
13330 This is the service type for the
13331 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
13332 service. The value for this service type is a
13333 @code{modem-manager-configuration} record.
13335 This service is part of @code{%desktop-services} (@pxref{Desktop
13339 @deftp {Data Type} modem-manager-configuration
13340 Data type representing the configuration of ModemManager.
13343 @item @code{modem-manager} (default: @code{modem-manager})
13344 The ModemManager package to use.
13349 @cindex USB_ModeSwitch
13350 @cindex Modeswitching
13352 @defvr {Scheme Variable} usb-modeswitch-service-type
13353 This is the service type for the
13354 @uref{http://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
13355 value for this service type is a @code{usb-modeswitch-configuration} record.
13357 When plugged in, some USB modems (and other USB devices) initially present
13358 themselves as a read-only storage medium and not as a modem. They need to be
13359 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
13360 installs udev rules to automatically modeswitch these devices when they are
13363 This service is part of @code{%desktop-services} (@pxref{Desktop
13367 @deftp {Data Type} usb-modeswitch-configuration
13368 Data type representing the configuration of USB_ModeSwitch.
13371 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
13372 The USB_ModeSwitch package providing the binaries for modeswitching.
13374 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
13375 The package providing the device data and udev rules file used by
13378 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
13379 Which config file to use for the USB_ModeSwitch dispatcher. By default the
13380 config file shipped with USB_ModeSwitch is used which disables logging to
13381 @file{/var/log} among other default settings. If set to @code{#f}, no config
13387 @cindex NetworkManager
13389 @defvr {Scheme Variable} network-manager-service-type
13390 This is the service type for the
13391 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
13392 service. The value for this service type is a
13393 @code{network-manager-configuration} record.
13395 This service is part of @code{%desktop-services} (@pxref{Desktop
13399 @deftp {Data Type} network-manager-configuration
13400 Data type representing the configuration of NetworkManager.
13403 @item @code{network-manager} (default: @code{network-manager})
13404 The NetworkManager package to use.
13406 @item @code{dns} (default: @code{"default"})
13407 Processing mode for DNS, which affects how NetworkManager uses the
13408 @code{resolv.conf} configuration file.
13412 NetworkManager will update @code{resolv.conf} to reflect the nameservers
13413 provided by currently active connections.
13416 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
13417 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
13418 then update @code{resolv.conf} to point to the local nameserver.
13420 With this setting, you can share your network connection. For example when
13421 you want to share your network connection to another laptop @i{via} an
13422 Ethernet cable, you can open @command{nm-connection-editor} and configure the
13423 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
13424 and reestablish the connection (or reboot).
13426 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
13427 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
13428 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
13429 browser on your host system, or connect to the VM @i{via} SSH
13430 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
13431 host-to-guest connection, run this command once:
13434 nmcli connection add type tun \
13435 connection.interface-name tap0 \
13436 tun.mode tap tun.owner $(id -u) \
13437 ipv4.method shared \
13438 ipv4.addresses 172.28.112.1/24
13441 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
13442 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
13443 @command{qemu-system-...}.
13446 NetworkManager will not modify @code{resolv.conf}.
13449 @item @code{vpn-plugins} (default: @code{'()})
13450 This is the list of available plugins for virtual private networks
13451 (VPNs). An example of this is the @code{network-manager-openvpn}
13452 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
13458 @deffn {Scheme Variable} connman-service-type
13459 This is the service type to run @url{https://01.org/connman,Connman},
13460 a network connection manager.
13462 Its value must be an
13463 @code{connman-configuration} record as in this example:
13466 (service connman-service-type
13467 (connman-configuration
13468 (disable-vpn? #t)))
13471 See below for details about @code{connman-configuration}.
13474 @deftp {Data Type} connman-configuration
13475 Data Type representing the configuration of connman.
13478 @item @code{connman} (default: @var{connman})
13479 The connman package to use.
13481 @item @code{disable-vpn?} (default: @code{#f})
13482 When true, disable connman's vpn plugin.
13486 @cindex WPA Supplicant
13487 @defvr {Scheme Variable} wpa-supplicant-service-type
13488 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
13489 supplicant}, an authentication daemon required to authenticate against
13490 encrypted WiFi or ethernet networks.
13493 @deftp {Data Type} wpa-supplicant-configuration
13494 Data type representing the configuration of WPA Supplicant.
13496 It takes the following parameters:
13499 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
13500 The WPA Supplicant package to use.
13502 @item @code{dbus?} (default: @code{#t})
13503 Whether to listen for requests on D-Bus.
13505 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
13506 Where to store the PID file.
13508 @item @code{interface} (default: @code{#f})
13509 If this is set, it must specify the name of a network interface that
13510 WPA supplicant will control.
13512 @item @code{config-file} (default: @code{#f})
13513 Optional configuration file to use.
13515 @item @code{extra-options} (default: @code{'()})
13516 List of additional command-line arguments to pass to the daemon.
13521 @defvr {Scheme Variable} iptables-service-type
13522 This is the service type to set up an iptables configuration. iptables is a
13523 packet filtering framework supported by the Linux kernel. This service
13524 supports configuring iptables for both IPv4 and IPv6. A simple example
13525 configuration rejecting all incoming connections except those to the ssh port
13529 (service iptables-service-type
13530 (iptables-configuration
13531 (ipv4-rules (plain-file "iptables.rules" "*filter
13535 -A INPUT -p tcp --dport 22 -j ACCEPT
13536 -A INPUT -j REJECT --reject-with icmp-port-unreachable
13539 (ipv6-rules (plain-file "ip6tables.rules" "*filter
13543 -A INPUT -p tcp --dport 22 -j ACCEPT
13544 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
13550 @deftp {Data Type} iptables-configuration
13551 The data type representing the configuration of iptables.
13554 @item @code{iptables} (default: @code{iptables})
13555 The iptables package that provides @code{iptables-restore} and
13556 @code{ip6tables-restore}.
13557 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
13558 The iptables rules to use. It will be passed to @code{iptables-restore}.
13559 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13561 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
13562 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
13563 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
13569 @defvr {Scheme Variable} nftables-service-type
13570 This is the service type to set up a nftables configuration. nftables is a
13571 netfilter project that aims to replace the existing iptables, ip6tables,
13572 arptables and ebtables framework. It provides a new packet filtering
13573 framework, a new user-space utility @command{nft}, and a compatibility layer
13574 for iptables. This service comes with a default ruleset
13575 @code{%default-nftables-ruleset} that rejecting all incomming connections
13576 except those to the ssh port 22. To use it, simply write:
13579 (service nftables-service-type)
13583 @deftp {Data Type} nftables-configuration
13584 The data type representing the configuration of nftables.
13587 @item @code{package} (default: @code{nftables})
13588 The nftables package that provides @command{nft}.
13589 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
13590 The nftables ruleset to use. This may be any ``file-like'' object
13591 (@pxref{G-Expressions, file-like objects}).
13595 @cindex NTP (Network Time Protocol), service
13596 @cindex ntpd, service for the Network Time Protocol daemon
13597 @cindex real time clock
13598 @defvr {Scheme Variable} ntp-service-type
13599 This is the type of the service running the @uref{http://www.ntp.org,
13600 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
13601 system clock synchronized with that of the specified NTP servers.
13603 The value of this service is an @code{ntpd-configuration} object, as described
13607 @deftp {Data Type} ntp-configuration
13608 This is the data type for the NTP service configuration.
13611 @item @code{servers} (default: @code{%ntp-servers})
13612 This is the list of servers (@code{<ntp-server>} records) with which
13613 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
13616 @item @code{allow-large-adjustment?} (default: @code{#t})
13617 This determines whether @command{ntpd} is allowed to make an initial
13618 adjustment of more than 1,000 seconds.
13620 @item @code{ntp} (default: @code{ntp})
13621 The NTP package to use.
13625 @defvr {Scheme Variable} %ntp-servers
13626 List of host names used as the default NTP servers. These are servers of the
13627 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
13630 @deftp {Data Type} ntp-server
13631 The data type representing the configuration of a NTP server.
13634 @item @code{type} (default: @code{'server})
13635 The type of the NTP server, given as a symbol. One of @code{'pool},
13636 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
13638 @item @code{address}
13639 The address of the server, as a string.
13641 @item @code{options}
13642 NTPD options to use with that specific server, given as a list of option names
13643 and/or of option names and values tuples. The following example define a server
13644 to use with the options @option{iburst} and @option{prefer}, as well as
13645 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
13650 (address "some.ntp.server.org")
13651 (options `(iburst (version 3) (maxpoll 16) prefer))))
13657 @deffn {Scheme Procedure} openntpd-service-type
13658 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
13659 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
13660 clock synchronized with that of the given servers.
13664 openntpd-service-type
13665 (openntpd-configuration
13666 (listen-on '("127.0.0.1" "::1"))
13667 (sensor '("udcf0 correction 70000"))
13668 (constraint-from '("www.gnu.org"))
13669 (constraints-from '("https://www.google.com/"))
13670 (allow-large-adjustment? #t)))
13675 @defvr {Scheme Variable} %openntpd-servers
13676 This variable is a list of the server addresses defined in
13677 @var{%ntp-servers}.
13680 @deftp {Data Type} openntpd-configuration
13682 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
13683 The openntpd executable to use.
13684 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
13685 A list of local IP addresses or hostnames the ntpd daemon should listen on.
13686 @item @code{query-from} (default: @code{'()})
13687 A list of local IP address the ntpd daemon should use for outgoing queries.
13688 @item @code{sensor} (default: @code{'()})
13689 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
13690 will listen to each sensor that actually exists and ignore non-existent ones.
13691 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
13693 @item @code{server} (default: @code{'()})
13694 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
13695 @item @code{servers} (default: @var{%openntp-servers})
13696 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
13697 @item @code{constraint-from} (default: @code{'()})
13698 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
13699 This time information is not used for precision but acts as an authenticated
13700 constraint, thereby reducing the impact of unauthenticated NTP
13701 man-in-the-middle attacks.
13702 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
13704 @item @code{constraints-from} (default: @code{'()})
13705 As with constraint from, specify a list of URLs, IP addresses or hostnames of
13706 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
13707 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
13708 @item @code{allow-large-adjustment?} (default: @code{#f})
13709 Determines if @code{ntpd} is allowed to make an initial adjustment of more
13715 @deffn {Scheme variable} inetd-service-type
13716 This service runs the @command{inetd} (@pxref{inetd invocation,,,
13717 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
13718 connections on internet sockets, and lazily starts the specified server
13719 program when a connection is made on one of these sockets.
13721 The value of this service is an @code{inetd-configuration} object. The
13722 following example configures the @command{inetd} daemon to provide the
13723 built-in @command{echo} service, as well as an smtp service which
13724 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
13725 gateway @code{hostname}:
13730 (inetd-configuration
13734 (socket-type 'stream)
13741 (socket-type 'stream)
13745 (program (file-append openssh "/bin/ssh"))
13747 '("ssh" "-qT" "-i" "/path/to/ssh_key"
13748 "-W" "smtp-server:25" "user@@hostname")))))))
13751 See below for more details about @code{inetd-configuration}.
13754 @deftp {Data Type} inetd-configuration
13755 Data type representing the configuration of @command{inetd}.
13758 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
13759 The @command{inetd} executable to use.
13761 @item @code{entries} (default: @code{'()})
13762 A list of @command{inetd} service entries. Each entry should be created
13763 by the @code{inetd-entry} constructor.
13767 @deftp {Data Type} inetd-entry
13768 Data type representing an entry in the @command{inetd} configuration.
13769 Each entry corresponds to a socket where @command{inetd} will listen for
13773 @item @code{node} (default: @code{#f})
13774 Optional string, a comma-separated list of local addresses
13775 @command{inetd} should use when listening for this service.
13776 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
13777 description of all options.
13779 A string, the name must correspond to an entry in @code{/etc/services}.
13780 @item @code{socket-type}
13781 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
13783 @item @code{protocol}
13784 A string, must correspond to an entry in @code{/etc/protocols}.
13785 @item @code{wait?} (default: @code{#t})
13786 Whether @command{inetd} should wait for the server to exit before
13787 listening to new service requests.
13789 A string containing the user (and, optionally, group) name of the user
13790 as whom the server should run. The group name can be specified in a
13791 suffix, separated by a colon or period, i.e.@: @code{"user"},
13792 @code{"user:group"} or @code{"user.group"}.
13793 @item @code{program} (default: @code{"internal"})
13794 The server program which will serve the requests, or @code{"internal"}
13795 if @command{inetd} should use a built-in service.
13796 @item @code{arguments} (default: @code{'()})
13797 A list strings or file-like objects, which are the server program's
13798 arguments, starting with the zeroth argument, i.e.@: the name of the
13799 program itself. For @command{inetd}'s internal services, this entry
13800 must be @code{'()} or @code{'("internal")}.
13803 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
13804 detailed discussion of each configuration field.
13808 @defvr {Scheme Variable} tor-service-type
13809 This is the type for a service that runs the @uref{https://torproject.org,
13810 Tor} anonymous networking daemon. The service is configured using a
13811 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
13812 @code{tor} unprivileged user, which is a member of the @code{tor} group.
13816 @deftp {Data Type} tor-configuration
13818 @item @code{tor} (default: @code{tor})
13819 The package that provides the Tor daemon. This package is expected to provide
13820 the daemon at @file{bin/tor} relative to its output directory. The default
13821 package is the @uref{https://www.torproject.org, Tor Project's}
13824 @item @code{config-file} (default: @code{(plain-file "empty" "")})
13825 The configuration file to use. It will be appended to a default configuration
13826 file, and the final configuration file will be passed to @code{tor} via its
13827 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
13828 file-like objects}). See @code{man tor} for details on the configuration file
13831 @item @code{hidden-services} (default: @code{'()})
13832 The list of @code{<hidden-service>} records to use. For any hidden service
13833 you include in this list, appropriate configuration to enable the hidden
13834 service will be automatically added to the default configuration file. You
13835 may conveniently create @code{<hidden-service>} records using the
13836 @code{tor-hidden-service} procedure described below.
13838 @item @code{socks-socket-type} (default: @code{'tcp})
13839 The default socket type that Tor should use for its SOCKS socket. This must
13840 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
13841 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
13842 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
13843 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
13846 If you want to customize the SOCKS socket in more detail, leave
13847 @code{socks-socket-type} at its default value of @code{'tcp} and use
13848 @code{config-file} to override the default by providing your own
13849 @code{SocksPort} option.
13853 @cindex hidden service
13854 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
13855 Define a new Tor @dfn{hidden service} called @var{name} and implementing
13856 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
13859 '((22 "127.0.0.1:22")
13860 (80 "127.0.0.1:8080"))
13863 In this example, port 22 of the hidden service is mapped to local port 22, and
13864 port 80 is mapped to local port 8080.
13866 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
13867 the @file{hostname} file contains the @code{.onion} host name for the hidden
13870 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
13871 project's documentation} for more information.
13874 The @code{(gnu services rsync)} module provides the following services:
13876 You might want an rsync daemon if you have files that you want available
13877 so anyone (or just yourself) can download existing files or upload new
13880 @deffn {Scheme Variable} rsync-service-type
13881 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
13882 The value for this service type is a
13883 @command{rsync-configuration} record as in this example:
13886 (service rsync-service-type)
13889 See below for details about @code{rsync-configuration}.
13892 @deftp {Data Type} rsync-configuration
13893 Data type representing the configuration for @code{rsync-service}.
13896 @item @code{package} (default: @var{rsync})
13897 @code{rsync} package to use.
13899 @item @code{port-number} (default: @code{873})
13900 TCP port on which @command{rsync} listens for incoming connections. If port
13901 is less than @code{1024} @command{rsync} needs to be started as the
13902 @code{root} user and group.
13904 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
13905 Name of the file where @command{rsync} writes its PID.
13907 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
13908 Name of the file where @command{rsync} writes its lock file.
13910 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
13911 Name of the file where @command{rsync} writes its log file.
13913 @item @code{use-chroot?} (default: @var{#t})
13914 Whether to use chroot for @command{rsync} shared directory.
13916 @item @code{share-path} (default: @file{/srv/rsync})
13917 Location of the @command{rsync} shared directory.
13919 @item @code{share-comment} (default: @code{"Rsync share"})
13920 Comment of the @command{rsync} shared directory.
13922 @item @code{read-only?} (default: @var{#f})
13923 Read-write permissions to shared directory.
13925 @item @code{timeout} (default: @code{300})
13926 I/O timeout in seconds.
13928 @item @code{user} (default: @var{"root"})
13929 Owner of the @code{rsync} process.
13931 @item @code{group} (default: @var{"root"})
13932 Group of the @code{rsync} process.
13934 @item @code{uid} (default: @var{"rsyncd"})
13935 User name or user ID that file transfers to and from that module should take
13936 place as when the daemon was run as @code{root}.
13938 @item @code{gid} (default: @var{"rsyncd"})
13939 Group name or group ID that will be used when accessing the module.
13944 Furthermore, @code{(gnu services ssh)} provides the following services.
13948 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
13949 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
13950 [#:allow-empty-passwords? #f] [#:root-login? #f] @
13951 [#:syslog-output? #t] [#:x11-forwarding? #t] @
13952 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
13953 [#:public-key-authentication? #t] [#:initialize? #t]
13954 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
13955 @var{host-key} must designate a file containing the host key, and readable
13958 When @var{daemonic?} is true, @command{lshd} will detach from the
13959 controlling terminal and log its output to syslogd, unless one sets
13960 @var{syslog-output?} to false. Obviously, it also makes lsh-service
13961 depend on existence of syslogd service. When @var{pid-file?} is true,
13962 @command{lshd} writes its PID to the file called @var{pid-file}.
13964 When @var{initialize?} is true, automatically create the seed and host key
13965 upon service activation if they do not exist yet. This may take long and
13966 require interaction.
13968 When @var{initialize?} is false, it is up to the user to initialize the
13969 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
13970 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
13971 basics,,, lsh, LSH Manual}).
13973 When @var{interfaces} is empty, lshd listens for connections on all the
13974 network interfaces; otherwise, @var{interfaces} must be a list of host names
13977 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
13978 passwords, and @var{root-login?} specifies whether to accept log-ins as
13981 The other options should be self-descriptive.
13986 @deffn {Scheme Variable} openssh-service-type
13987 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
13988 shell daemon, @command{sshd}. Its value must be an
13989 @code{openssh-configuration} record as in this example:
13992 (service openssh-service-type
13993 (openssh-configuration
13994 (x11-forwarding? #t)
13995 (permit-root-login 'without-password)
13997 `(("alice" ,(local-file "alice.pub"))
13998 ("bob" ,(local-file "bob.pub"))))))
14001 See below for details about @code{openssh-configuration}.
14003 This service can be extended with extra authorized keys, as in this
14007 (service-extension openssh-service-type
14008 (const `(("charlie"
14009 ,(local-file "charlie.pub")))))
14013 @deftp {Data Type} openssh-configuration
14014 This is the configuration record for OpenSSH's @command{sshd}.
14017 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
14018 Name of the file where @command{sshd} writes its PID.
14020 @item @code{port-number} (default: @code{22})
14021 TCP port on which @command{sshd} listens for incoming connections.
14023 @item @code{permit-root-login} (default: @code{#f})
14024 This field determines whether and when to allow logins as root. If
14025 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
14026 If it's the symbol @code{'without-password}, then root logins are
14027 permitted but not with password-based authentication.
14029 @item @code{allow-empty-passwords?} (default: @code{#f})
14030 When true, users with empty passwords may log in. When false, they may
14033 @item @code{password-authentication?} (default: @code{#t})
14034 When true, users may log in with their password. When false, they have
14035 other authentication methods.
14037 @item @code{public-key-authentication?} (default: @code{#t})
14038 When true, users may log in using public key authentication. When
14039 false, users have to use other authentication method.
14041 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
14042 This is used only by protocol version 2.
14044 @item @code{x11-forwarding?} (default: @code{#f})
14045 When true, forwarding of X11 graphical client connections is
14046 enabled---in other words, @command{ssh} options @option{-X} and
14047 @option{-Y} will work.
14049 @item @code{allow-agent-forwarding?} (default: @code{#t})
14050 Whether to allow agent forwarding.
14052 @item @code{allow-tcp-forwarding?} (default: @code{#t})
14053 Whether to allow TCP forwarding.
14055 @item @code{gateway-ports?} (default: @code{#f})
14056 Whether to allow gateway ports.
14058 @item @code{challenge-response-authentication?} (default: @code{#f})
14059 Specifies whether challenge response authentication is allowed (e.g.@: via
14062 @item @code{use-pam?} (default: @code{#t})
14063 Enables the Pluggable Authentication Module interface. If set to
14064 @code{#t}, this will enable PAM authentication using
14065 @code{challenge-response-authentication?} and
14066 @code{password-authentication?}, in addition to PAM account and session
14067 module processing for all authentication types.
14069 Because PAM challenge response authentication usually serves an
14070 equivalent role to password authentication, you should disable either
14071 @code{challenge-response-authentication?} or
14072 @code{password-authentication?}.
14074 @item @code{print-last-log?} (default: @code{#t})
14075 Specifies whether @command{sshd} should print the date and time of the
14076 last user login when a user logs in interactively.
14078 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
14079 Configures external subsystems (e.g.@: file transfer daemon).
14081 This is a list of two-element lists, each of which containing the
14082 subsystem name and a command (with optional arguments) to execute upon
14085 The command @command{internal-sftp} implements an in-process SFTP
14086 server. Alternately, one can specify the @command{sftp-server} command:
14088 (service openssh-service-type
14089 (openssh-configuration
14091 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
14094 @item @code{accepted-environment} (default: @code{'()})
14095 List of strings describing which environment variables may be exported.
14097 Each string gets on its own line. See the @code{AcceptEnv} option in
14098 @code{man sshd_config}.
14100 This example allows ssh-clients to export the @code{COLORTERM} variable.
14101 It is set by terminal emulators, which support colors. You can use it in
14102 your shell's resource file to enable colors for the prompt and commands
14103 if this variable is set.
14106 (service openssh-service-type
14107 (openssh-configuration
14108 (accepted-environment '("COLORTERM"))))
14111 @item @code{authorized-keys} (default: @code{'()})
14112 @cindex authorized keys, SSH
14113 @cindex SSH authorized keys
14114 This is the list of authorized keys. Each element of the list is a user
14115 name followed by one or more file-like objects that represent SSH public
14119 (openssh-configuration
14121 `(("rekado" ,(local-file "rekado.pub"))
14122 ("chris" ,(local-file "chris.pub"))
14123 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
14127 registers the specified public keys for user accounts @code{rekado},
14128 @code{chris}, and @code{root}.
14130 Additional authorized keys can be specified @i{via}
14131 @code{service-extension}.
14133 Note that this does @emph{not} interfere with the use of
14134 @file{~/.ssh/authorized_keys}.
14136 @item @code{log-level} (default: @code{'info})
14137 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
14138 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
14139 page for @file{sshd_config} for the full list of level names.
14141 @item @code{extra-content} (default: @code{""})
14142 This field can be used to append arbitrary text to the configuration file. It
14143 is especially useful for elaborate configurations that cannot be expressed
14144 otherwise. This configuration, for example, would generally disable root
14145 logins, but permit them from one specific IP address:
14148 (openssh-configuration
14150 Match Address 192.168.0.1
14151 PermitRootLogin yes"))
14157 @deffn {Scheme Procedure} dropbear-service [@var{config}]
14158 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
14159 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
14162 For example, to specify a Dropbear service listening on port 1234, add
14163 this call to the operating system's @code{services} field:
14166 (dropbear-service (dropbear-configuration
14167 (port-number 1234)))
14171 @deftp {Data Type} dropbear-configuration
14172 This data type represents the configuration of a Dropbear SSH daemon.
14175 @item @code{dropbear} (default: @var{dropbear})
14176 The Dropbear package to use.
14178 @item @code{port-number} (default: 22)
14179 The TCP port where the daemon waits for incoming connections.
14181 @item @code{syslog-output?} (default: @code{#t})
14182 Whether to enable syslog output.
14184 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
14185 File name of the daemon's PID file.
14187 @item @code{root-login?} (default: @code{#f})
14188 Whether to allow @code{root} logins.
14190 @item @code{allow-empty-passwords?} (default: @code{#f})
14191 Whether to allow empty passwords.
14193 @item @code{password-authentication?} (default: @code{#t})
14194 Whether to enable password-based authentication.
14198 @defvr {Scheme Variable} %facebook-host-aliases
14199 This variable contains a string for use in @file{/etc/hosts}
14200 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
14201 line contains a entry that maps a known server name of the Facebook
14202 on-line service---e.g., @code{www.facebook.com}---to the local
14203 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
14205 This variable is typically used in the @code{hosts-file} field of an
14206 @code{operating-system} declaration (@pxref{operating-system Reference,
14207 @file{/etc/hosts}}):
14210 (use-modules (gnu) (guix))
14213 (host-name "mymachine")
14216 ;; Create a /etc/hosts file with aliases for "localhost"
14217 ;; and "mymachine", as well as for Facebook servers.
14218 (plain-file "hosts"
14219 (string-append (local-host-aliases host-name)
14220 %facebook-host-aliases))))
14223 This mechanism can prevent programs running locally, such as Web
14224 browsers, from accessing Facebook.
14227 The @code{(gnu services avahi)} provides the following definition.
14229 @defvr {Scheme Variable} avahi-service-type
14230 This is the service that runs @command{avahi-daemon}, a system-wide
14231 mDNS/DNS-SD responder that allows for service discovery and
14232 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
14233 Its value must be a @code{zero-configuration} record---see below.
14235 This service extends the name service cache daemon (nscd) so that it can
14236 resolve @code{.local} host names using
14237 @uref{http://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
14238 Service Switch}, for information on host name resolution.
14240 Additionally, add the @var{avahi} package to the system profile so that
14241 commands such as @command{avahi-browse} are directly usable.
14244 @deftp {Data Type} avahi-configuration
14245 Data type representation the configuration for Avahi.
14249 @item @code{host-name} (default: @code{#f})
14250 If different from @code{#f}, use that as the host name to
14251 publish for this machine; otherwise, use the machine's actual host name.
14253 @item @code{publish?} (default: @code{#t})
14254 When true, allow host names and services to be published (broadcast) over the
14257 @item @code{publish-workstation?} (default: @code{#t})
14258 When true, @command{avahi-daemon} publishes the machine's host name and IP
14259 address via mDNS on the local network. To view the host names published on
14260 your local network, you can run:
14263 avahi-browse _workstation._tcp
14266 @item @code{wide-area?} (default: @code{#f})
14267 When true, DNS-SD over unicast DNS is enabled.
14269 @item @code{ipv4?} (default: @code{#t})
14270 @itemx @code{ipv6?} (default: @code{#t})
14271 These fields determine whether to use IPv4/IPv6 sockets.
14273 @item @code{domains-to-browse} (default: @code{'()})
14274 This is a list of domains to browse.
14278 @deffn {Scheme Variable} openvswitch-service-type
14279 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
14280 service, whose value should be an @code{openvswitch-configuration}
14284 @deftp {Data Type} openvswitch-configuration
14285 Data type representing the configuration of Open vSwitch, a multilayer
14286 virtual switch which is designed to enable massive network automation
14287 through programmatic extension.
14290 @item @code{package} (default: @var{openvswitch})
14291 Package object of the Open vSwitch.
14296 @defvr {Scheme Variable} pagekite-service-type
14297 This is the service type for the @uref{https://pagekite.net, PageKite} service,
14298 a tunneling solution for making localhost servers publicly visible, even from
14299 behind restrictive firewalls or NAT without forwarded ports. The value for
14300 this service type is a @code{pagekite-configuration} record.
14302 Here's an example exposing the local HTTP and SSH daemons:
14305 (service pagekite-service-type
14306 (pagekite-configuration
14307 (kites '("http:@@kitename:localhost:80:@@kitesecret"
14308 "raw/22:@@kitename:localhost:22:@@kitesecret"))
14309 (extra-file "/etc/pagekite.rc")))
14313 @deftp {Data Type} pagekite-configuration
14314 Data type representing the configuration of PageKite.
14317 @item @code{package} (default: @var{pagekite})
14318 Package object of PageKite.
14320 @item @code{kitename} (default: @code{#f})
14321 PageKite name for authenticating to the frontend server.
14323 @item @code{kitesecret} (default: @code{#f})
14324 Shared secret for authenticating to the frontend server. You should probably
14325 put this inside @code{extra-file} instead.
14327 @item @code{frontend} (default: @code{#f})
14328 Connect to the named PageKite frontend server instead of the
14329 @uref{https://pagekite.net,,pagekite.net} service.
14331 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
14332 List of service kites to use. Exposes HTTP on port 80 by default. The format
14333 is @code{proto:kitename:host:port:secret}.
14335 @item @code{extra-file} (default: @code{#f})
14336 Extra configuration file to read, which you are expected to create manually.
14337 Use this to add additional options and manage shared secrets out-of-band.
14343 @subsection X Window
14346 @cindex X Window System
14347 @cindex login manager
14348 Support for the X Window graphical display system---specifically
14349 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
14350 there is no @code{xorg-service} procedure. Instead, the X server is
14351 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
14354 @cindex GNOME, login manager
14355 GDM of course allows users to log in into window managers and desktop
14356 environments other than GNOME; for those using GNOME, GDM is required for
14357 features such as automatic screen locking.
14359 @cindex window manager
14360 To use X11, you must install at least one @dfn{window manager}---for
14361 example the @code{windowmaker} or @code{openbox} packages---preferably
14362 by adding it to the @code{packages} field of your operating system
14363 definition (@pxref{operating-system Reference, system-wide packages}).
14365 @defvr {Scheme Variable} gdm-service-type
14366 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
14367 Desktop Manager} (GDM), a program that manages graphical display servers and
14368 handles graphical user logins. Its value must be a @code{gdm-configuration}
14371 @cindex session types (X11)
14372 @cindex X11 session types
14373 GDM looks for @dfn{session types} described by the @file{.desktop} files in
14374 @file{/run/current-system/profile/share/xsessions} and allows users to choose
14375 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
14376 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
14377 set of packages automatically makes them available at the log-in screen.
14379 In addition, @file{~/.xsession} files are honored. When available,
14380 @file{~/.xsession} must be an executable that starts a window manager
14381 and/or other X clients.
14384 @deftp {Data Type} gdm-configuration
14386 @item @code{auto-login?} (default: @code{#f})
14387 @itemx @code{default-user} (default: @code{#f})
14388 When @code{auto-login?} is false, GDM presents a log-in screen.
14390 When @code{auto-login?} is true, GDM logs in directly as
14391 @code{default-user}.
14393 @item @code{debug?} (default: @code{#f})
14394 When true, GDM writes debug messages to its log.
14396 @item @code{gnome-shell-assets} (default: ...)
14397 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
14399 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
14400 Configuration of the Xorg graphical server.
14402 @item @code{xsession} (default: @code{(xinitrc)})
14403 Script to run before starting a X session.
14405 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
14406 File name of the @code{dbus-daemon} executable.
14408 @item @code{gdm} (default: @code{gdm})
14409 The GDM package to use.
14413 @defvr {Scheme Variable} slim-service-type
14414 This is the type for the SLiM graphical login manager for X11.
14416 Like GDM, SLiM looks for session types described by @file{.desktop} files and
14417 allows users to choose a session from the log-in screen using @kbd{F1}. It
14418 also honors @file{~/.xsession} files.
14420 Unlike GDM, SLiM does not spawn the user session on a different VT after
14421 logging in, which means that you can only start one graphical session. If you
14422 want to be able to run multiple graphical sessions at the same time you have
14423 to add multiple SLiM services to your system services. The following example
14424 shows how to replace the default GDM service with two SLiM services on tty7
14428 (use-modules (gnu services)
14429 (gnu services desktop)
14430 (gnu services xorg)
14431 (srfi srfi-1)) ;for 'remove'
14435 (services (cons* (service slim-service-type (slim-configuration
14438 (service slim-service-type (slim-configuration
14441 (remove (lambda (service)
14442 (eq? (service-kind service) gdm-service-type))
14443 %desktop-services))))
14448 @deftp {Data Type} slim-configuration
14449 Data type representing the configuration of @code{slim-service-type}.
14452 @item @code{allow-empty-passwords?} (default: @code{#t})
14453 Whether to allow logins with empty passwords.
14455 @item @code{auto-login?} (default: @code{#f})
14456 @itemx @code{default-user} (default: @code{""})
14457 When @code{auto-login?} is false, SLiM presents a log-in screen.
14459 When @code{auto-login?} is true, SLiM logs in directly as
14460 @code{default-user}.
14462 @item @code{theme} (default: @code{%default-slim-theme})
14463 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
14464 The graphical theme to use and its name.
14466 @item @code{auto-login-session} (default: @code{#f})
14467 If true, this must be the name of the executable to start as the default
14468 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
14470 If false, a session described by one of the available @file{.desktop}
14471 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
14475 You must install at least one window manager in the system profile or in
14476 your user profile. Failing to do that, if @code{auto-login-session} is
14477 false, you will be unable to log in.
14480 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14481 Configuration of the Xorg graphical server.
14483 @item @code{display} (default @code{":0"})
14484 The display on which to start the Xorg graphical server.
14486 @item @code{vt} (default @code{"vt7"})
14487 The VT on which to start the Xorg graphical server.
14489 @item @code{xauth} (default: @code{xauth})
14490 The XAuth package to use.
14492 @item @code{shepherd} (default: @code{shepherd})
14493 The Shepherd package used when invoking @command{halt} and
14496 @item @code{sessreg} (default: @code{sessreg})
14497 The sessreg package used in order to register the session.
14499 @item @code{slim} (default: @code{slim})
14500 The SLiM package to use.
14504 @defvr {Scheme Variable} %default-theme
14505 @defvrx {Scheme Variable} %default-theme-name
14506 The default SLiM theme and its name.
14510 @deftp {Data Type} sddm-configuration
14511 This is the data type representing the sddm service configuration.
14514 @item @code{display-server} (default: "x11")
14515 Select display server to use for the greeter. Valid values are "x11"
14518 @item @code{numlock} (default: "on")
14519 Valid values are "on", "off" or "none".
14521 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
14522 Command to run when halting.
14524 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
14525 Command to run when rebooting.
14527 @item @code{theme} (default "maldives")
14528 Theme to use. Default themes provided by SDDM are "elarun", "maldives" or "maya".
14530 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
14531 Directory to look for themes.
14533 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
14534 Directory to look for faces.
14536 @item @code{default-path} (default "/run/current-system/profile/bin")
14537 Default PATH to use.
14539 @item @code{minimum-uid} (default: 1000)
14540 Minimum UID displayed in SDDM and allowed for log-in.
14542 @item @code{maximum-uid} (default: 2000)
14543 Maximum UID to display in SDDM.
14545 @item @code{remember-last-user?} (default #t)
14546 Remember last user.
14548 @item @code{remember-last-session?} (default #t)
14549 Remember last session.
14551 @item @code{hide-users} (default "")
14552 Usernames to hide from SDDM greeter.
14554 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
14555 Users with shells listed will be hidden from the SDDM greeter.
14557 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
14558 Script to run before starting a wayland session.
14560 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
14561 Directory to look for desktop files starting wayland sessions.
14563 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
14564 Configuration of the Xorg graphical server.
14566 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
14569 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
14572 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
14573 Script to run after starting xorg-server.
14575 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
14576 Script to run before stopping xorg-server.
14578 @item @code{xsession-command} (default: @code{xinitrc})
14579 Script to run before starting a X session.
14581 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
14582 Directory to look for desktop files starting X sessions.
14584 @item @code{minimum-vt} (default: 7)
14587 @item @code{auto-login-user} (default "")
14588 User to use for auto-login.
14590 @item @code{auto-login-session} (default "")
14591 Desktop file to use for auto-login.
14593 @item @code{relogin?} (default #f)
14594 Relogin after logout.
14599 @cindex login manager
14601 @defvr {Scheme Variable} sddm-service-type
14602 This is the type of the service to run the
14603 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
14604 must be a @code{sddm-configuration} record (see below).
14606 Here's an example use:
14609 (service sddm-service-type
14610 (sddm-configuration
14611 (auto-login-user "alice")
14612 (auto-login-session "xfce.desktop")))
14616 @deftp {Data Type} sddm-configuration
14617 This data type represents the configuration of the SDDM login manager.
14618 The available fields are:
14621 @item @code{sddm} (default: @code{sddm})
14622 The SDDM package to use.
14624 @item @code{display-server} (default: @code{"x11"})
14625 This must be either @code{"x11"} or @code{"wayland"}.
14627 @c FIXME: Add more fields.
14629 @item @code{auto-login-user} (default: @code{""})
14630 If non-empty, this is the user account under which to log in
14633 @item @code{auto-login-session} (default: @code{""})
14634 If non-empty, this is the @file{.desktop} file name to use as the
14635 auto-login session.
14639 @cindex Xorg, configuration
14640 @deftp {Data Type} xorg-configuration
14641 This data type represents the configuration of the Xorg graphical display
14642 server. Note that there is not Xorg service; instead, the X server is started
14643 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
14644 of these display managers aggregates an @code{xorg-configuration} record.
14647 @item @code{modules} (default: @code{%default-xorg-modules})
14648 This is a list of @dfn{module packages} loaded by the Xorg
14649 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
14651 @item @code{fonts} (default: @code{%default-xorg-fonts})
14652 This is a list of font directories to add to the server's @dfn{font path}.
14654 @item @code{drivers} (default: @code{'()})
14655 This must be either the empty list, in which case Xorg chooses a graphics
14656 driver automatically, or a list of driver names that will be tried in this
14657 order---e.g., @code{("modesetting" "vesa")}.
14659 @item @code{resolutions} (default: @code{'()})
14660 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
14661 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
14664 @cindex keyboard layout, for Xorg
14665 @cindex keymap, for Xorg
14666 @item @code{keyboard-layout} (default: @code{#f})
14667 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
14668 English (``qwerty'') for a 105-key PC keyboard.
14670 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
14671 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
14672 information on how to specify the keyboard layout.
14674 @item @code{extra-config} (default: @code{'()})
14675 This is a list of strings or objects appended to the configuration file. It
14676 is used to pass extra text to be added verbatim to the configuration file.
14678 @item @code{server} (default: @code{xorg-server})
14679 This is the package providing the Xorg server.
14681 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
14682 This is the list of command-line arguments to pass to the X server. The
14683 default is @code{-nolisten tcp}.
14687 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
14688 [@var{login-manager-service-type}]
14689 Tell the log-in manager (of type @var{login-manager-service-type}) to use
14690 @var{config}, an @code{<xorg-configuration>} record.
14692 Since the Xorg configuration is embedded in the log-in manager's
14693 configuration---e.g., @code{gdm-configuration}---this procedure provides a
14694 shorthand to set the Xorg configuration.
14697 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
14698 Return a @code{startx} script in which the modules, fonts, etc. specified
14699 in @var{config}, are available. The result should be used in place of
14702 Usually the X server is started by a login manager.
14706 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
14707 Add @var{package}, a package for a screen locker or screen saver whose
14708 command is @var{program}, to the set of setuid programs and add a PAM entry
14709 for it. For example:
14712 (screen-locker-service xlockmore "xlock")
14715 makes the good ol' XlockMore usable.
14719 @node Printing Services
14720 @subsection Printing Services
14722 @cindex printer support with CUPS
14723 The @code{(gnu services cups)} module provides a Guix service definition
14724 for the CUPS printing service. To add printer support to a Guix
14725 system, add a @code{cups-service} to the operating system definition:
14727 @deffn {Scheme Variable} cups-service-type
14728 The service type for the CUPS print server. Its value should be a valid
14729 CUPS configuration (see below). To use the default settings, simply
14732 (service cups-service-type)
14736 The CUPS configuration controls the basic things about your CUPS
14737 installation: what interfaces it listens on, what to do if a print job
14738 fails, how much logging to do, and so on. To actually add a printer,
14739 you have to visit the @url{http://localhost:631} URL, or use a tool such
14740 as GNOME's printer configuration services. By default, configuring a
14741 CUPS service will generate a self-signed certificate if needed, for
14742 secure connections to the print server.
14744 Suppose you want to enable the Web interface of CUPS and also add
14745 support for Epson printers @i{via} the @code{escpr} package and for HP
14746 printers @i{via} the @code{hplip-minimal} package. You can do that directly,
14747 like this (you need to use the @code{(gnu packages cups)} module):
14750 (service cups-service-type
14751 (cups-configuration
14752 (web-interface? #t)
14754 (list cups-filters escpr hplip-minimal))))
14757 Note: If you wish to use the Qt5 based GUI which comes with the hplip
14758 package then it is suggested that you install the @code{hplip} package,
14759 either in your OS configuration file or as your user.
14761 The available configuration parameters follow. Each parameter
14762 definition is preceded by its type; for example, @samp{string-list foo}
14763 indicates that the @code{foo} parameter should be specified as a list of
14764 strings. There is also a way to specify the configuration as a string,
14765 if you have an old @code{cupsd.conf} file that you want to port over
14766 from some other system; see the end for more details.
14768 @c The following documentation was initially generated by
14769 @c (generate-documentation) in (gnu services cups). Manually maintained
14770 @c documentation is better, so we shouldn't hesitate to edit below as
14771 @c needed. However if the change you want to make to this documentation
14772 @c can be done in an automated way, it's probably easier to change
14773 @c (generate-documentation) than to make it below and have to deal with
14774 @c the churn as CUPS updates.
14777 Available @code{cups-configuration} fields are:
14779 @deftypevr {@code{cups-configuration} parameter} package cups
14783 @deftypevr {@code{cups-configuration} parameter} package-list extensions
14784 Drivers and other extensions to the CUPS package.
14787 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
14788 Configuration of where to write logs, what directories to use for print
14789 spools, and related privileged configuration parameters.
14791 Available @code{files-configuration} fields are:
14793 @deftypevr {@code{files-configuration} parameter} log-location access-log
14794 Defines the access log filename. Specifying a blank filename disables
14795 access log generation. The value @code{stderr} causes log entries to be
14796 sent to the standard error file when the scheduler is running in the
14797 foreground, or to the system log daemon when run in the background. The
14798 value @code{syslog} causes log entries to be sent to the system log
14799 daemon. The server name may be included in filenames using the string
14800 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
14802 Defaults to @samp{"/var/log/cups/access_log"}.
14805 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
14806 Where CUPS should cache data.
14808 Defaults to @samp{"/var/cache/cups"}.
14811 @deftypevr {@code{files-configuration} parameter} string config-file-perm
14812 Specifies the permissions for all configuration files that the scheduler
14815 Note that the permissions for the printers.conf file are currently
14816 masked to only allow access from the scheduler user (typically root).
14817 This is done because printer device URIs sometimes contain sensitive
14818 authentication information that should not be generally known on the
14819 system. There is no way to disable this security feature.
14821 Defaults to @samp{"0640"}.
14824 @deftypevr {@code{files-configuration} parameter} log-location error-log
14825 Defines the error log filename. Specifying a blank filename disables
14826 error log generation. The value @code{stderr} causes log entries to be
14827 sent to the standard error file when the scheduler is running in the
14828 foreground, or to the system log daemon when run in the background. The
14829 value @code{syslog} causes log entries to be sent to the system log
14830 daemon. The server name may be included in filenames using the string
14831 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
14833 Defaults to @samp{"/var/log/cups/error_log"}.
14836 @deftypevr {@code{files-configuration} parameter} string fatal-errors
14837 Specifies which errors are fatal, causing the scheduler to exit. The
14842 No errors are fatal.
14845 All of the errors below are fatal.
14848 Browsing initialization errors are fatal, for example failed connections
14849 to the DNS-SD daemon.
14852 Configuration file syntax errors are fatal.
14855 Listen or Port errors are fatal, except for IPv6 failures on the
14856 loopback or @code{any} addresses.
14859 Log file creation or write errors are fatal.
14862 Bad startup file permissions are fatal, for example shared TLS
14863 certificate and key files with world-read permissions.
14866 Defaults to @samp{"all -browse"}.
14869 @deftypevr {@code{files-configuration} parameter} boolean file-device?
14870 Specifies whether the file pseudo-device can be used for new printer
14871 queues. The URI @uref{file:///dev/null} is always allowed.
14873 Defaults to @samp{#f}.
14876 @deftypevr {@code{files-configuration} parameter} string group
14877 Specifies the group name or ID that will be used when executing external
14880 Defaults to @samp{"lp"}.
14883 @deftypevr {@code{files-configuration} parameter} string log-file-perm
14884 Specifies the permissions for all log files that the scheduler writes.
14886 Defaults to @samp{"0644"}.
14889 @deftypevr {@code{files-configuration} parameter} log-location page-log
14890 Defines the page log filename. Specifying a blank filename disables
14891 page log generation. The value @code{stderr} causes log entries to be
14892 sent to the standard error file when the scheduler is running in the
14893 foreground, or to the system log daemon when run in the background. The
14894 value @code{syslog} causes log entries to be sent to the system log
14895 daemon. The server name may be included in filenames using the string
14896 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
14898 Defaults to @samp{"/var/log/cups/page_log"}.
14901 @deftypevr {@code{files-configuration} parameter} string remote-root
14902 Specifies the username that is associated with unauthenticated accesses
14903 by clients claiming to be the root user. The default is @code{remroot}.
14905 Defaults to @samp{"remroot"}.
14908 @deftypevr {@code{files-configuration} parameter} file-name request-root
14909 Specifies the directory that contains print jobs and other HTTP request
14912 Defaults to @samp{"/var/spool/cups"}.
14915 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
14916 Specifies the level of security sandboxing that is applied to print
14917 filters, backends, and other child processes of the scheduler; either
14918 @code{relaxed} or @code{strict}. This directive is currently only
14919 used/supported on macOS.
14921 Defaults to @samp{strict}.
14924 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
14925 Specifies the location of TLS certificates and private keys. CUPS will
14926 look for public and private keys in this directory: a @code{.crt} files
14927 for PEM-encoded certificates and corresponding @code{.key} files for
14928 PEM-encoded private keys.
14930 Defaults to @samp{"/etc/cups/ssl"}.
14933 @deftypevr {@code{files-configuration} parameter} file-name server-root
14934 Specifies the directory containing the server configuration files.
14936 Defaults to @samp{"/etc/cups"}.
14939 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
14940 Specifies whether the scheduler calls fsync(2) after writing
14941 configuration or state files.
14943 Defaults to @samp{#f}.
14946 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
14947 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
14950 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
14951 Specifies the directory where temporary files are stored.
14953 Defaults to @samp{"/var/spool/cups/tmp"}.
14956 @deftypevr {@code{files-configuration} parameter} string user
14957 Specifies the user name or ID that is used when running external
14960 Defaults to @samp{"lp"}.
14963 @deftypevr {@code{files-configuration} parameter} string set-env
14964 Set the specified environment variable to be passed to child processes.
14966 Defaults to @samp{"variable value"}.
14970 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
14971 Specifies the logging level for the AccessLog file. The @code{config}
14972 level logs when printers and classes are added, deleted, or modified and
14973 when configuration files are accessed or updated. The @code{actions}
14974 level logs when print jobs are submitted, held, released, modified, or
14975 canceled, and any of the conditions for @code{config}. The @code{all}
14976 level logs all requests.
14978 Defaults to @samp{actions}.
14981 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
14982 Specifies whether to purge job history data automatically when it is no
14983 longer required for quotas.
14985 Defaults to @samp{#f}.
14988 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
14989 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
14990 For example, @samp{"_cups" "_print"} will tell network clients that both
14991 CUPS sharing and IPP Everywhere are supported.
14993 Defaults to @samp{"_cups"}.
14996 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
14997 Specifies which protocols to use for local printer sharing.
14999 Defaults to @samp{dnssd}.
15002 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
15003 Specifies whether the CUPS web interface is advertised.
15005 Defaults to @samp{#f}.
15008 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
15009 Specifies whether shared printers are advertised.
15011 Defaults to @samp{#f}.
15014 @deftypevr {@code{cups-configuration} parameter} string classification
15015 Specifies the security classification of the server. Any valid banner
15016 name can be used, including "classified", "confidential", "secret",
15017 "topsecret", and "unclassified", or the banner can be omitted to disable
15018 secure printing functions.
15020 Defaults to @samp{""}.
15023 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
15024 Specifies whether users may override the classification (cover page) of
15025 individual print jobs using the @code{job-sheets} option.
15027 Defaults to @samp{#f}.
15030 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
15031 Specifies the default type of authentication to use.
15033 Defaults to @samp{Basic}.
15036 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
15037 Specifies whether encryption will be used for authenticated requests.
15039 Defaults to @samp{Required}.
15042 @deftypevr {@code{cups-configuration} parameter} string default-language
15043 Specifies the default language to use for text and web content.
15045 Defaults to @samp{"en"}.
15048 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
15049 Specifies the default paper size for new print queues. @samp{"Auto"}
15050 uses a locale-specific default, while @samp{"None"} specifies there is
15051 no default paper size. Specific size names are typically
15052 @samp{"Letter"} or @samp{"A4"}.
15054 Defaults to @samp{"Auto"}.
15057 @deftypevr {@code{cups-configuration} parameter} string default-policy
15058 Specifies the default access policy to use.
15060 Defaults to @samp{"default"}.
15063 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
15064 Specifies whether local printers are shared by default.
15066 Defaults to @samp{#t}.
15069 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
15070 Specifies the delay for updating of configuration and state files, in
15071 seconds. A value of 0 causes the update to happen as soon as possible,
15072 typically within a few milliseconds.
15074 Defaults to @samp{30}.
15077 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
15078 Specifies what to do when an error occurs. Possible values are
15079 @code{abort-job}, which will discard the failed print job;
15080 @code{retry-job}, which will retry the job at a later time;
15081 @code{retry-current-job}, which retries the failed job immediately; and
15082 @code{stop-printer}, which stops the printer.
15084 Defaults to @samp{stop-printer}.
15087 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
15088 Specifies the maximum cost of filters that are run concurrently, which
15089 can be used to minimize disk, memory, and CPU resource problems. A
15090 limit of 0 disables filter limiting. An average print to a
15091 non-PostScript printer needs a filter limit of about 200. A PostScript
15092 printer needs about half that (100). Setting the limit below these
15093 thresholds will effectively limit the scheduler to printing a single job
15096 Defaults to @samp{0}.
15099 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
15100 Specifies the scheduling priority of filters that are run to print a
15101 job. The nice value ranges from 0, the highest priority, to 19, the
15104 Defaults to @samp{0}.
15107 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
15108 Specifies whether to do reverse lookups on connecting clients. The
15109 @code{double} setting causes @code{cupsd} to verify that the hostname
15110 resolved from the address matches one of the addresses returned for that
15111 hostname. Double lookups also prevent clients with unregistered
15112 addresses from connecting to your server. Only set this option to
15113 @code{#t} or @code{double} if absolutely required.
15115 Defaults to @samp{#f}.
15118 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
15119 Specifies the number of seconds to wait before killing the filters and
15120 backend associated with a canceled or held job.
15122 Defaults to @samp{30}.
15125 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
15126 Specifies the interval between retries of jobs in seconds. This is
15127 typically used for fax queues but can also be used with normal print
15128 queues whose error policy is @code{retry-job} or
15129 @code{retry-current-job}.
15131 Defaults to @samp{30}.
15134 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
15135 Specifies the number of retries that are done for jobs. This is
15136 typically used for fax queues but can also be used with normal print
15137 queues whose error policy is @code{retry-job} or
15138 @code{retry-current-job}.
15140 Defaults to @samp{5}.
15143 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
15144 Specifies whether to support HTTP keep-alive connections.
15146 Defaults to @samp{#t}.
15149 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
15150 Specifies how long an idle client connection remains open, in seconds.
15152 Defaults to @samp{30}.
15155 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
15156 Specifies the maximum size of print files, IPP requests, and HTML form
15157 data. A limit of 0 disables the limit check.
15159 Defaults to @samp{0}.
15162 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
15163 Listens on the specified interfaces for connections. Valid values are
15164 of the form @var{address}:@var{port}, where @var{address} is either an
15165 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
15166 indicate all addresses. Values can also be file names of local UNIX
15167 domain sockets. The Listen directive is similar to the Port directive
15168 but allows you to restrict access to specific interfaces or networks.
15171 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
15172 Specifies the number of pending connections that will be allowed. This
15173 normally only affects very busy servers that have reached the MaxClients
15174 limit, but can also be triggered by large numbers of simultaneous
15175 connections. When the limit is reached, the operating system will
15176 refuse additional connections until the scheduler can accept the pending
15179 Defaults to @samp{128}.
15182 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
15183 Specifies a set of additional access controls.
15185 Available @code{location-access-controls} fields are:
15187 @deftypevr {@code{location-access-controls} parameter} file-name path
15188 Specifies the URI path to which the access control applies.
15191 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
15192 Access controls for all access to this path, in the same format as the
15193 @code{access-controls} of @code{operation-access-control}.
15195 Defaults to @samp{()}.
15198 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
15199 Access controls for method-specific access to this path.
15201 Defaults to @samp{()}.
15203 Available @code{method-access-controls} fields are:
15205 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
15206 If @code{#t}, apply access controls to all methods except the listed
15207 methods. Otherwise apply to only the listed methods.
15209 Defaults to @samp{#f}.
15212 @deftypevr {@code{method-access-controls} parameter} method-list methods
15213 Methods to which this access control applies.
15215 Defaults to @samp{()}.
15218 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
15219 Access control directives, as a list of strings. Each string should be
15220 one directive, such as "Order allow,deny".
15222 Defaults to @samp{()}.
15227 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
15228 Specifies the number of debugging messages that are retained for logging
15229 if an error occurs in a print job. Debug messages are logged regardless
15230 of the LogLevel setting.
15232 Defaults to @samp{100}.
15235 @deftypevr {@code{cups-configuration} parameter} log-level log-level
15236 Specifies the level of logging for the ErrorLog file. The value
15237 @code{none} stops all logging while @code{debug2} logs everything.
15239 Defaults to @samp{info}.
15242 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
15243 Specifies the format of the date and time in the log files. The value
15244 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
15246 Defaults to @samp{standard}.
15249 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
15250 Specifies the maximum number of simultaneous clients that are allowed by
15253 Defaults to @samp{100}.
15256 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
15257 Specifies the maximum number of simultaneous clients that are allowed
15258 from a single address.
15260 Defaults to @samp{100}.
15263 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
15264 Specifies the maximum number of copies that a user can print of each
15267 Defaults to @samp{9999}.
15270 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
15271 Specifies the maximum time a job may remain in the @code{indefinite}
15272 hold state before it is canceled. A value of 0 disables cancellation of
15275 Defaults to @samp{0}.
15278 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
15279 Specifies the maximum number of simultaneous jobs that are allowed. Set
15280 to 0 to allow an unlimited number of jobs.
15282 Defaults to @samp{500}.
15285 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
15286 Specifies the maximum number of simultaneous jobs that are allowed per
15287 printer. A value of 0 allows up to MaxJobs jobs per printer.
15289 Defaults to @samp{0}.
15292 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
15293 Specifies the maximum number of simultaneous jobs that are allowed per
15294 user. A value of 0 allows up to MaxJobs jobs per user.
15296 Defaults to @samp{0}.
15299 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
15300 Specifies the maximum time a job may take to print before it is
15301 canceled, in seconds. Set to 0 to disable cancellation of "stuck" jobs.
15303 Defaults to @samp{10800}.
15306 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
15307 Specifies the maximum size of the log files before they are rotated, in
15308 bytes. The value 0 disables log rotation.
15310 Defaults to @samp{1048576}.
15313 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
15314 Specifies the maximum amount of time to allow between files in a
15315 multiple file print job, in seconds.
15317 Defaults to @samp{300}.
15320 @deftypevr {@code{cups-configuration} parameter} string page-log-format
15321 Specifies the format of PageLog lines. Sequences beginning with percent
15322 (@samp{%}) characters are replaced with the corresponding information,
15323 while all other characters are copied literally. The following percent
15324 sequences are recognized:
15328 insert a single percent character
15331 insert the value of the specified IPP attribute
15334 insert the number of copies for the current page
15337 insert the current page number
15340 insert the current date and time in common log format
15346 insert the printer name
15349 insert the username
15352 A value of the empty string disables page logging. The string @code{%p
15353 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
15354 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
15357 Defaults to @samp{""}.
15360 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
15361 Passes the specified environment variable(s) to child processes; a list
15364 Defaults to @samp{()}.
15367 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
15368 Specifies named access control policies.
15370 Available @code{policy-configuration} fields are:
15372 @deftypevr {@code{policy-configuration} parameter} string name
15373 Name of the policy.
15376 @deftypevr {@code{policy-configuration} parameter} string job-private-access
15377 Specifies an access list for a job's private values. @code{@@ACL} maps
15378 to the printer's requesting-user-name-allowed or
15379 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15380 owner. @code{@@SYSTEM} maps to the groups listed for the
15381 @code{system-group} field of the @code{files-config} configuration,
15382 which is reified into the @code{cups-files.conf(5)} file. Other
15383 possible elements of the access list include specific user names, and
15384 @code{@@@var{group}} to indicate members of a specific group. The
15385 access list may also be simply @code{all} or @code{default}.
15387 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15390 @deftypevr {@code{policy-configuration} parameter} string job-private-values
15391 Specifies the list of job values to make private, or @code{all},
15392 @code{default}, or @code{none}.
15394 Defaults to @samp{"job-name job-originating-host-name
15395 job-originating-user-name phone"}.
15398 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
15399 Specifies an access list for a subscription's private values.
15400 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
15401 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
15402 owner. @code{@@SYSTEM} maps to the groups listed for the
15403 @code{system-group} field of the @code{files-config} configuration,
15404 which is reified into the @code{cups-files.conf(5)} file. Other
15405 possible elements of the access list include specific user names, and
15406 @code{@@@var{group}} to indicate members of a specific group. The
15407 access list may also be simply @code{all} or @code{default}.
15409 Defaults to @samp{"@@OWNER @@SYSTEM"}.
15412 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
15413 Specifies the list of job values to make private, or @code{all},
15414 @code{default}, or @code{none}.
15416 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
15417 notify-subscriber-user-name notify-user-data"}.
15420 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
15421 Access control by IPP operation.
15423 Defaults to @samp{()}.
15427 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
15428 Specifies whether job files (documents) are preserved after a job is
15429 printed. If a numeric value is specified, job files are preserved for
15430 the indicated number of seconds after printing. Otherwise a boolean
15431 value applies indefinitely.
15433 Defaults to @samp{86400}.
15436 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
15437 Specifies whether the job history is preserved after a job is printed.
15438 If a numeric value is specified, the job history is preserved for the
15439 indicated number of seconds after printing. If @code{#t}, the job
15440 history is preserved until the MaxJobs limit is reached.
15442 Defaults to @samp{#t}.
15445 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
15446 Specifies the amount of time to wait for job completion before
15447 restarting the scheduler.
15449 Defaults to @samp{30}.
15452 @deftypevr {@code{cups-configuration} parameter} string rip-cache
15453 Specifies the maximum amount of memory to use when converting documents
15454 into bitmaps for a printer.
15456 Defaults to @samp{"128m"}.
15459 @deftypevr {@code{cups-configuration} parameter} string server-admin
15460 Specifies the email address of the server administrator.
15462 Defaults to @samp{"root@@localhost.localdomain"}.
15465 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
15466 The ServerAlias directive is used for HTTP Host header validation when
15467 clients connect to the scheduler from external interfaces. Using the
15468 special name @code{*} can expose your system to known browser-based DNS
15469 rebinding attacks, even when accessing sites through a firewall. If the
15470 auto-discovery of alternate names does not work, we recommend listing
15471 each alternate name with a ServerAlias directive instead of using
15474 Defaults to @samp{*}.
15477 @deftypevr {@code{cups-configuration} parameter} string server-name
15478 Specifies the fully-qualified host name of the server.
15480 Defaults to @samp{"localhost"}.
15483 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
15484 Specifies what information is included in the Server header of HTTP
15485 responses. @code{None} disables the Server header. @code{ProductOnly}
15486 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
15487 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
15488 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
15489 the output of the @code{uname} command. @code{Full} reports @code{CUPS
15490 2.0.0 (@var{uname}) IPP/2.0}.
15492 Defaults to @samp{Minimal}.
15495 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
15496 Listens on the specified interfaces for encrypted connections. Valid
15497 values are of the form @var{address}:@var{port}, where @var{address} is
15498 either an IPv6 address enclosed in brackets, an IPv4 address, or
15499 @code{*} to indicate all addresses.
15501 Defaults to @samp{()}.
15504 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
15505 Sets encryption options. By default, CUPS only supports encryption
15506 using TLS v1.0 or higher using known secure cipher suites. Security is
15507 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
15508 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
15509 suites, which are required for some older clients. The @code{AllowSSL3} option
15510 enables SSL v3.0, which is required for some older clients that do not support
15511 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
15512 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
15513 protocol version to TLS v1.1.
15515 Defaults to @samp{()}.
15518 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
15519 Specifies whether the scheduler requires clients to strictly adhere to
15520 the IPP specifications.
15522 Defaults to @samp{#f}.
15525 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
15526 Specifies the HTTP request timeout, in seconds.
15528 Defaults to @samp{300}.
15532 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
15533 Specifies whether the web interface is enabled.
15535 Defaults to @samp{#f}.
15538 At this point you're probably thinking ``oh dear, Guix manual, I like
15539 you but you can stop already with the configuration options''. Indeed.
15540 However, one more point: it could be that you have an existing
15541 @code{cupsd.conf} that you want to use. In that case, you can pass an
15542 @code{opaque-cups-configuration} as the configuration of a
15543 @code{cups-service-type}.
15545 Available @code{opaque-cups-configuration} fields are:
15547 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
15551 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
15552 The contents of the @code{cupsd.conf}, as a string.
15555 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
15556 The contents of the @code{cups-files.conf} file, as a string.
15559 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
15560 strings of the same name, you could instantiate a CUPS service like
15564 (service cups-service-type
15565 (opaque-cups-configuration
15566 (cupsd.conf cupsd.conf)
15567 (cups-files.conf cups-files.conf)))
15571 @node Desktop Services
15572 @subsection Desktop Services
15574 The @code{(gnu services desktop)} module provides services that are
15575 usually useful in the context of a ``desktop'' setup---that is, on a
15576 machine running a graphical display server, possibly with graphical user
15577 interfaces, etc. It also defines services that provide specific desktop
15578 environments like GNOME, Xfce or MATE.
15580 To simplify things, the module defines a variable containing the set of
15581 services that users typically expect on a machine with a graphical
15582 environment and networking:
15584 @defvr {Scheme Variable} %desktop-services
15585 This is a list of services that builds upon @code{%base-services} and
15586 adds or adjusts services for a typical ``desktop'' setup.
15588 In particular, it adds a graphical login manager (@pxref{X Window,
15589 @code{gdm-service-type}}), screen lockers, a network management tool
15590 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
15591 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
15592 energy and color management services, the @code{elogind} login and seat
15593 manager, the Polkit privilege service, the GeoClue location service, the
15594 AccountsService daemon that allows authorized users change system passwords,
15595 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
15596 name service switch service configured to be able to use @code{nss-mdns}
15597 (@pxref{Name Service Switch, mDNS}).
15600 The @code{%desktop-services} variable can be used as the @code{services}
15601 field of an @code{operating-system} declaration (@pxref{operating-system
15602 Reference, @code{services}}).
15604 Additionally, the @code{gnome-desktop-service-type},
15605 @code{xfce-desktop-service}, @code{mate-desktop-service-type} and
15606 @code{enlightenment-desktop-service-type} procedures can add GNOME, Xfce, MATE
15607 and/or Enlightenment to a system. To ``add GNOME'' means that system-level
15608 services like the backlight adjustment helpers and the power management
15609 utilities are added to the system, extending @code{polkit} and @code{dbus}
15610 appropriately, allowing GNOME to operate with elevated privileges on a
15611 limited number of special-purpose system interfaces. Additionally,
15612 adding a service made by @code{gnome-desktop-service-type} adds the GNOME
15613 metapackage to the system profile. Likewise, adding the Xfce service
15614 not only adds the @code{xfce} metapackage to the system profile, but it
15615 also gives the Thunar file manager the ability to open a ``root-mode''
15616 file management window, if the user authenticates using the
15617 administrator's password via the standard polkit graphical interface.
15618 To ``add MATE'' means that @code{polkit} and @code{dbus} are extended
15619 appropriately, allowing MATE to operate with elevated privileges on a
15620 limited number of special-purpose system interfaces. Additionally,
15621 adding a service of type @code{mate-desktop-service-type} adds the MATE
15622 metapackage to the system profile. ``Adding Enlightenment'' means that
15623 @code{dbus} is extended appropriately, and several of Enlightenment's binaries
15624 are set as setuid, allowing Enlightenment's screen locker and other
15625 functionality to work as expected.
15627 The desktop environments in Guix use the Xorg display server by
15628 default. If you'd like to use the newer display server protocol
15629 called Wayland, you need to use the @code{sddm-service} instead of
15630 GDM as the graphical login manager. You should then
15631 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
15632 also try starting GNOME on Wayland manually from a TTY with the
15633 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
15634 gnome-session``. Currently only GNOME has support for Wayland.
15636 @defvr {Scheme Variable} gnome-desktop-service-type
15637 This is the type of the service that adds the @uref{https://www.gnome.org,
15638 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
15639 object (see below.)
15641 This service adds the @code{gnome} package to the system profile, and extends
15642 polkit with the actions from @code{gnome-settings-daemon}.
15645 @deftp {Data Type} gnome-desktop-configuration
15646 Configuration record for the GNOME desktop environment.
15649 @item @code{gnome} (default: @code{gnome})
15650 The GNOME package to use.
15654 @defvr {Scheme Variable} xfce-desktop-service-type
15655 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
15656 desktop environment. Its value is an @code{xfce-desktop-configuration} object
15659 This service adds the @code{xfce} package to the system profile, and
15660 extends polkit with the ability for @code{thunar} to manipulate the file
15661 system as root from within a user session, after the user has authenticated
15662 with the administrator's password.
15665 @deftp {Data Type} xfce-desktop-configuration
15666 Configuration record for the Xfce desktop environment.
15669 @item @code{xfce} (default: @code{xfce})
15670 The Xfce package to use.
15674 @deffn {Scheme Variable} mate-desktop-service-type
15675 This is the type of the service that runs the @uref{https://mate-desktop.org/,
15676 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
15677 object (see below.)
15679 This service adds the @code{mate} package to the system
15680 profile, and extends polkit with the actions from
15681 @code{mate-settings-daemon}.
15684 @deftp {Data Type} mate-desktop-configuration
15685 Configuration record for the MATE desktop environment.
15688 @item @code{mate} (default: @code{mate})
15689 The MATE package to use.
15693 @deffn {Scheme Variable} enlightenment-desktop-service-type
15694 Return a service that adds the @code{enlightenment} package to the system
15695 profile, and extends dbus with actions from @code{efl}.
15698 @deftp {Data Type} enlightenment-desktop-service-configuration
15700 @item @code{enlightenment} (default: @code{enlightenment})
15701 The enlightenment package to use.
15705 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
15706 the default @code{%desktop-services} variable doesn't include any of
15707 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
15708 @code{%desktop-services} in the @code{services} field of your
15709 @code{operating-system}:
15712 (use-modules (gnu))
15713 (use-service-modules desktop)
15716 ;; cons* adds items to the list given as its last argument.
15717 (services (cons* (service gnome-desktop-service-type)
15718 (service xfce-desktop-service)
15719 %desktop-services))
15723 These desktop environments will then be available as options in the
15724 graphical login window.
15726 The actual service definitions included in @code{%desktop-services} and
15727 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
15728 are described below.
15730 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
15731 Return a service that runs the ``system bus'', using @var{dbus}, with
15732 support for @var{services}.
15734 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
15735 facility. Its system bus is used to allow system services to communicate
15736 and to be notified of system-wide events.
15738 @var{services} must be a list of packages that provide an
15739 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
15740 and policy files. For example, to allow avahi-daemon to use the system bus,
15741 @var{services} must be equal to @code{(list avahi)}.
15744 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
15745 Return a service that runs the @code{elogind} login and
15746 seat management daemon. @uref{https://github.com/elogind/elogind,
15747 Elogind} exposes a D-Bus interface that can be used to know which users
15748 are logged in, know what kind of sessions they have open, suspend the
15749 system, inhibit system suspend, reboot the system, and other tasks.
15751 Elogind handles most system-level power events for a computer, for
15752 example suspending the system when a lid is closed, or shutting it down
15753 when the power button is pressed.
15755 The @var{config} keyword argument specifies the configuration for
15756 elogind, and should be the result of an @code{(elogind-configuration
15757 (@var{parameter} @var{value})...)} invocation. Available parameters and
15758 their default values are:
15761 @item kill-user-processes?
15763 @item kill-only-users
15765 @item kill-exclude-users
15767 @item inhibit-delay-max-seconds
15769 @item handle-power-key
15771 @item handle-suspend-key
15773 @item handle-hibernate-key
15775 @item handle-lid-switch
15777 @item handle-lid-switch-docked
15779 @item power-key-ignore-inhibited?
15781 @item suspend-key-ignore-inhibited?
15783 @item hibernate-key-ignore-inhibited?
15785 @item lid-switch-ignore-inhibited?
15787 @item holdoff-timeout-seconds
15791 @item idle-action-seconds
15793 @item runtime-directory-size-percent
15795 @item runtime-directory-size
15799 @item suspend-state
15800 @code{("mem" "standby" "freeze")}
15803 @item hibernate-state
15805 @item hibernate-mode
15806 @code{("platform" "shutdown")}
15807 @item hybrid-sleep-state
15809 @item hybrid-sleep-mode
15810 @code{("suspend" "platform" "shutdown")}
15814 @deffn {Scheme Procedure} accountsservice-service @
15815 [#:accountsservice @var{accountsservice}]
15816 Return a service that runs AccountsService, a system service that can
15817 list available accounts, change their passwords, and so on.
15818 AccountsService integrates with PolicyKit to enable unprivileged users
15819 to acquire the capability to modify their system configuration.
15820 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
15821 accountsservice web site} for more information.
15823 The @var{accountsservice} keyword argument is the @code{accountsservice}
15824 package to expose as a service.
15827 @deffn {Scheme Procedure} polkit-service @
15828 [#:polkit @var{polkit}]
15829 Return a service that runs the
15830 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
15831 management service}, which allows system administrators to grant access to
15832 privileged operations in a structured way. By querying the Polkit service, a
15833 privileged system component can know when it should grant additional
15834 capabilities to ordinary users. For example, an ordinary user can be granted
15835 the capability to suspend the system if the user is logged in locally.
15838 @defvr {Scheme Variable} polkit-wheel-service
15839 Service that adds the @code{wheel} group as admins to the Polkit
15840 service. This makes it so that users in the @code{wheel} group are queried
15841 for their own passwords when performing administrative actions instead of
15842 @code{root}'s, similar to the behaviour used by @code{sudo}.
15845 @defvr {Scheme Variable} upower-service-type
15846 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
15847 system-wide monitor for power consumption and battery levels, with the given
15848 configuration settings.
15850 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
15851 notably used by GNOME.
15854 @deftp {Data Type} upower-configuration
15855 Data type representation the configuration for UPower.
15859 @item @code{upower} (default: @var{upower})
15860 Package to use for @code{upower}.
15862 @item @code{watts-up-pro?} (default: @code{#f})
15863 Enable the Watts Up Pro device.
15865 @item @code{poll-batteries?} (default: @code{#t})
15866 Enable polling the kernel for battery level changes.
15868 @item @code{ignore-lid?} (default: @code{#f})
15869 Ignore the lid state, this can be useful if it's incorrect on a device.
15871 @item @code{use-percentage-for-policy?} (default: @code{#f})
15872 Whether battery percentage based policy should be used. The default is to use
15873 the time left, change to @code{#t} to use the percentage.
15875 @item @code{percentage-low} (default: @code{10})
15876 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15877 at which the battery is considered low.
15879 @item @code{percentage-critical} (default: @code{3})
15880 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15881 at which the battery is considered critical.
15883 @item @code{percentage-action} (default: @code{2})
15884 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
15885 at which action will be taken.
15887 @item @code{time-low} (default: @code{1200})
15888 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15889 seconds at which the battery is considered low.
15891 @item @code{time-critical} (default: @code{300})
15892 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15893 seconds at which the battery is considered critical.
15895 @item @code{time-action} (default: @code{120})
15896 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
15897 seconds at which action will be taken.
15899 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
15900 The action taken when @code{percentage-action} or @code{time-action} is
15901 reached (depending on the configuration of @code{use-percentage-for-policy?}).
15903 Possible values are:
15913 @code{'hybrid-sleep}.
15919 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
15920 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
15921 UDisks}, a @dfn{disk management} daemon that provides user interfaces with
15922 notifications and ways to mount/unmount disks. Programs that talk to UDisks
15923 include the @command{udisksctl} command, part of UDisks, and GNOME Disks.
15926 @deffn {Scheme Variable} colord-service-type
15927 This is the type of the service that runs @command{colord}, a system
15928 service with a D-Bus
15929 interface to manage the color profiles of input and output devices such as
15930 screens and scanners. It is notably used by the GNOME Color Manager graphical
15931 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
15932 site} for more information.
15935 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
15936 Return a configuration allowing an application to access GeoClue
15937 location data. @var{name} is the Desktop ID of the application, without
15938 the @code{.desktop} part. If @var{allowed?} is true, the application
15939 will have access to location information by default. The boolean
15940 @var{system?} value indicates whether an application is a system component
15941 or not. Finally @var{users} is a list of UIDs of all users for which
15942 this application is allowed location info access. An empty users list
15943 means that all users are allowed.
15946 @cindex scanner access
15947 @deffn {Scheme Procedure} sane-service-type
15948 This service provides access to scanners @i{via}
15949 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
15953 @defvr {Scheme Variable} %standard-geoclue-applications
15954 The standard list of well-known GeoClue application configurations,
15955 granting authority to the GNOME date-and-time utility to ask for the
15956 current location in order to set the time zone, and allowing the
15957 IceCat and Epiphany web browsers to request location information.
15958 IceCat and Epiphany both query the user before allowing a web page to
15959 know the user's location.
15962 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
15963 [#:whitelist '()] @
15964 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
15965 [#:submit-data? #f]
15966 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
15967 [#:submission-nick "geoclue"] @
15968 [#:applications %standard-geoclue-applications]
15969 Return a service that runs the GeoClue location service. This service
15970 provides a D-Bus interface to allow applications to request access to a
15971 user's physical location, and optionally to add information to online
15972 location databases. See
15973 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
15974 web site} for more information.
15977 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
15978 [@w{#:auto-enable? #f}]
15979 Return a service that runs the @command{bluetoothd} daemon, which
15980 manages all the Bluetooth devices and provides a number of D-Bus
15981 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
15982 powered automatically at boot, which can be useful when using a
15983 bluetooth keyboard or mouse.
15985 Users need to be in the @code{lp} group to access the D-Bus service.
15988 @defvr {Scheme Variable} gnome-keyring-service-type
15989 This is the type of the service that adds the
15990 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
15991 value is a @code{gnome-keyring-configuration} object (see below.)
15993 This service adds the @code{gnome-keyring} package to the system profile
15994 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
15995 a user's login keyring when they log in or setting its password with passwd.
15998 @deftp {Data Type} gnome-keyring-configuration
15999 Configuration record for the GNOME Keyring service.
16002 @item @code{keyring} (default: @code{gnome-keyring})
16003 The GNOME keyring package to use.
16005 @item @code{pam-services}
16006 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
16007 services to extend, where @var{service} is the name of an existing
16008 service to extend and @var{kind} is one of @code{login} or
16011 If @code{login} is given, it adds an optional
16012 @code{pam_gnome_keyring.so} to the auth block without arguments and to
16013 the session block with @code{auto_start}. If @code{passwd} is given, it
16014 adds an optional @code{pam_gnome_keyring.so} to the password block
16017 By default, this field contains ``gdm-password'' with the value @code{login}
16018 and ``passwd'' is with the value @code{passwd}.
16023 @node Sound Services
16024 @subsection Sound Services
16026 @cindex sound support
16028 @cindex PulseAudio, sound support
16030 The @code{(gnu services sound)} module provides a service to configure the
16031 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
16032 preferred ALSA output driver.
16034 @deffn {Scheme Variable} alsa-service-type
16035 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
16036 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
16037 configuration file. The value for this type is a @command{alsa-configuration}
16038 record as in this example:
16041 (service alsa-service-type)
16044 See below for details about @code{alsa-configuration}.
16047 @deftp {Data Type} alsa-configuration
16048 Data type representing the configuration for @code{alsa-service}.
16051 @item @code{alsa-plugins} (default: @var{alsa-plugins})
16052 @code{alsa-plugins} package to use.
16054 @item @code{pulseaudio?} (default: @var{#t})
16055 Whether ALSA applications should transparently be made to use the
16056 @uref{http://www.pulseaudio.org/, PulseAudio} sound server.
16058 Using PulseAudio allows you to run several sound-producing applications
16059 at the same time and to individual control them @i{via}
16060 @command{pavucontrol}, among other things.
16062 @item @code{extra-options} (default: @var{""})
16063 String to append to the @file{/etc/asound.conf} file.
16068 Individual users who want to override the system configuration of ALSA can do
16069 it with the @file{~/.asoundrc} file:
16072 # In guix, we have to specify the absolute path for plugins.
16074 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
16077 # Routing ALSA to jack:
16078 # <http://jackaudio.org/faq/routing_alsa.html>.
16082 0 system:playback_1
16083 1 system:playback_2
16100 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
16103 @deffn {Scheme Variable} pulseaudio-service-type
16104 This is the type for the @uref{http://www.pulseaudio.org/, PulseAudio}
16105 sound server. It exists to allow system overrides of the default settings
16106 via @code{pulseaudio-configuration}, see below.
16109 This service on its own does not ensure, that the @code{pulseaudio} package
16110 exists on your machine. It merely adds configuration files for it, as
16111 detailed below. In the (admittedly unlikely) case, that you find yourself
16112 without a @code{pulseaudio} package, consider enabling it through the
16113 @code{alsa-service-type} above.
16117 @deftp {Data Type} pulseaudio-configuration
16118 Data type representing the configuration for @code{pulseaudio-service}.
16121 @item @var{client-conf} (default: @code{'()})
16122 List of settings to set in @file{client.conf}.
16123 Accepts a list of strings or a symbol-value pairs. A string will be
16124 inserted as-is with a newline added. A pair will be formatted as
16125 ``key = value'', again with a newline added.
16127 @item @var{daemon-conf} (default: @code{'((flat-volumes . no))})
16128 List of settings to set in @file{daemon.conf}, formatted just like
16131 @item @var{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
16132 Script file to use as as @file{default.pa}.
16134 @item @var{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
16135 Script file to use as as @file{system.pa}.
16139 @deffn {Scheme Variable} ladspa-service-type
16140 This service sets the @var{LADSPA_PATH} variable, so that programs, which
16141 respect it, e.g. PulseAudio, can load LADSPA plugins.
16143 The following example will setup the service to enable modules from the
16144 @code{swh-plugins} package:
16147 (service ladspa-service-type
16148 (ladspa-configuration (plugins (list swh-plugins))))
16151 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
16156 @node Database Services
16157 @subsection Database Services
16161 The @code{(gnu services databases)} module provides the following services.
16163 @deffn {Scheme Procedure} postgresql-service [#:postgresql postgresql] @
16164 [#:config-file] [#:data-directory ``/var/lib/postgresql/data''] @
16165 [#:port 5432] [#:locale ``en_US.utf8''] [#:extension-packages '()]
16166 Return a service that runs @var{postgresql}, the PostgreSQL database
16169 The PostgreSQL daemon loads its runtime configuration from @var{config-file},
16170 creates a database cluster with @var{locale} as the default
16171 locale, stored in @var{data-directory}. It then listens on @var{port}.
16173 @cindex postgresql extension-packages
16174 Additional extensions are loaded from packages listed in
16175 @var{extension-packages}. Extensions are available at runtime. For instance,
16176 to create a geographic database using the @code{postgis} extension, a user can
16177 configure the postgresql-service as in this example:
16181 (use-package-modules databases geo)
16185 ;; postgresql is required to run `psql' but postgis is not required for
16186 ;; proper operation.
16187 (packages (cons* postgresql %base-packages))
16190 (postgresql-service #:extension-packages (list postgis))
16194 Then the extension becomes visible and you can initialise an empty geographic
16195 database in this way:
16199 > create database postgistest;
16200 > \connect postgistest;
16201 > create extension postgis;
16202 > create extension postgis_topology;
16205 There is no need to add this field for contrib extensions such as hstore or
16206 dblink as they are already loadable by postgresql. This field is only
16207 required to add extensions provided by other packages.
16210 @deffn {Scheme Procedure} mysql-service [#:config (mysql-configuration)]
16211 Return a service that runs @command{mysqld}, the MySQL or MariaDB
16214 The optional @var{config} argument specifies the configuration for
16215 @command{mysqld}, which should be a @code{<mysql-configuration>} object.
16218 @deftp {Data Type} mysql-configuration
16219 Data type representing the configuration of @var{mysql-service}.
16222 @item @code{mysql} (default: @var{mariadb})
16223 Package object of the MySQL database server, can be either @var{mariadb}
16226 For MySQL, a temporary root password will be displayed at activation time.
16227 For MariaDB, the root password is empty.
16229 @item @code{port} (default: @code{3306})
16230 TCP port on which the database server listens for incoming connections.
16234 @defvr {Scheme Variable} memcached-service-type
16235 This is the service type for the @uref{https://memcached.org/,
16236 Memcached} service, which provides a distributed in memory cache. The
16237 value for the service type is a @code{memcached-configuration} object.
16241 (service memcached-service-type)
16244 @deftp {Data Type} memcached-configuration
16245 Data type representing the configuration of memcached.
16248 @item @code{memcached} (default: @code{memcached})
16249 The Memcached package to use.
16251 @item @code{interfaces} (default: @code{'("0.0.0.0")})
16252 Network interfaces on which to listen.
16254 @item @code{tcp-port} (default: @code{11211})
16255 Port on which to accept connections on,
16257 @item @code{udp-port} (default: @code{11211})
16258 Port on which to accept UDP connections on, a value of 0 will disable
16259 listening on a UDP socket.
16261 @item @code{additional-options} (default: @code{'()})
16262 Additional command line options to pass to @code{memcached}.
16266 @defvr {Scheme Variable} mongodb-service-type
16267 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
16268 The value for the service type is a @code{mongodb-configuration} object.
16272 (service mongodb-service-type)
16275 @deftp {Data Type} mongodb-configuration
16276 Data type representing the configuration of mongodb.
16279 @item @code{mongodb} (default: @code{mongodb})
16280 The MongoDB package to use.
16282 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
16283 The configuration file for MongoDB.
16285 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
16286 This value is used to create the directory, so that it exists and is
16287 owned by the mongodb user. It should match the data-directory which
16288 MongoDB is configured to use through the configuration file.
16292 @defvr {Scheme Variable} redis-service-type
16293 This is the service type for the @uref{https://redis.io/, Redis}
16294 key/value store, whose value is a @code{redis-configuration} object.
16297 @deftp {Data Type} redis-configuration
16298 Data type representing the configuration of redis.
16301 @item @code{redis} (default: @code{redis})
16302 The Redis package to use.
16304 @item @code{bind} (default: @code{"127.0.0.1"})
16305 Network interface on which to listen.
16307 @item @code{port} (default: @code{6379})
16308 Port on which to accept connections on, a value of 0 will disable
16309 listening on a TCP socket.
16311 @item @code{working-directory} (default: @code{"/var/lib/redis"})
16312 Directory in which to store the database and related files.
16316 @node Mail Services
16317 @subsection Mail Services
16321 The @code{(gnu services mail)} module provides Guix service definitions
16322 for email services: IMAP, POP3, and LMTP servers, as well as mail
16323 transport agents (MTAs). Lots of acronyms! These services are detailed
16324 in the subsections below.
16326 @subsubheading Dovecot Service
16328 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
16329 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
16332 By default, Dovecot does not need much configuration; the default
16333 configuration object created by @code{(dovecot-configuration)} will
16334 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
16335 certificate will be generated for TLS-protected connections, though
16336 Dovecot will also listen on cleartext ports by default. There are a
16337 number of options, though, which mail administrators might need to change,
16338 and as is the case with other services, Guix allows the system
16339 administrator to specify these parameters via a uniform Scheme interface.
16341 For example, to specify that mail is located at @code{maildir~/.mail},
16342 one would instantiate the Dovecot service like this:
16345 (dovecot-service #:config
16346 (dovecot-configuration
16347 (mail-location "maildir:~/.mail")))
16350 The available configuration parameters follow. Each parameter
16351 definition is preceded by its type; for example, @samp{string-list foo}
16352 indicates that the @code{foo} parameter should be specified as a list of
16353 strings. There is also a way to specify the configuration as a string,
16354 if you have an old @code{dovecot.conf} file that you want to port over
16355 from some other system; see the end for more details.
16357 @c The following documentation was initially generated by
16358 @c (generate-documentation) in (gnu services mail). Manually maintained
16359 @c documentation is better, so we shouldn't hesitate to edit below as
16360 @c needed. However if the change you want to make to this documentation
16361 @c can be done in an automated way, it's probably easier to change
16362 @c (generate-documentation) than to make it below and have to deal with
16363 @c the churn as dovecot updates.
16365 Available @code{dovecot-configuration} fields are:
16367 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
16368 The dovecot package.
16371 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
16372 A list of IPs or hosts where to listen for connections. @samp{*}
16373 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
16374 interfaces. If you want to specify non-default ports or anything more
16375 complex, customize the address and port fields of the
16376 @samp{inet-listener} of the specific services you are interested in.
16379 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
16380 List of protocols we want to serve. Available protocols include
16381 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
16383 Available @code{protocol-configuration} fields are:
16385 @deftypevr {@code{protocol-configuration} parameter} string name
16386 The name of the protocol.
16389 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
16390 UNIX socket path to the master authentication server to find users.
16391 This is used by imap (for shared users) and lda.
16392 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
16395 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
16396 Space separated list of plugins to load.
16399 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
16400 Maximum number of IMAP connections allowed for a user from each IP
16401 address. NOTE: The username is compared case-sensitively.
16402 Defaults to @samp{10}.
16407 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
16408 List of services to enable. Available services include @samp{imap},
16409 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
16412 Available @code{service-configuration} fields are:
16414 @deftypevr {@code{service-configuration} parameter} string kind
16415 The service kind. Valid values include @code{director},
16416 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
16417 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
16418 @code{tcpwrap}, @code{quota-warning}, or anything else.
16421 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
16422 Listeners for the service. A listener is either a
16423 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
16424 an @code{inet-listener-configuration}.
16425 Defaults to @samp{()}.
16427 Available @code{unix-listener-configuration} fields are:
16429 @deftypevr {@code{unix-listener-configuration} parameter} string path
16430 Path to the file, relative to @code{base-dir} field. This is also used as
16434 @deftypevr {@code{unix-listener-configuration} parameter} string mode
16435 The access mode for the socket.
16436 Defaults to @samp{"0600"}.
16439 @deftypevr {@code{unix-listener-configuration} parameter} string user
16440 The user to own the socket.
16441 Defaults to @samp{""}.
16444 @deftypevr {@code{unix-listener-configuration} parameter} string group
16445 The group to own the socket.
16446 Defaults to @samp{""}.
16450 Available @code{fifo-listener-configuration} fields are:
16452 @deftypevr {@code{fifo-listener-configuration} parameter} string path
16453 Path to the file, relative to @code{base-dir} field. This is also used as
16457 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
16458 The access mode for the socket.
16459 Defaults to @samp{"0600"}.
16462 @deftypevr {@code{fifo-listener-configuration} parameter} string user
16463 The user to own the socket.
16464 Defaults to @samp{""}.
16467 @deftypevr {@code{fifo-listener-configuration} parameter} string group
16468 The group to own the socket.
16469 Defaults to @samp{""}.
16473 Available @code{inet-listener-configuration} fields are:
16475 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
16476 The protocol to listen for.
16479 @deftypevr {@code{inet-listener-configuration} parameter} string address
16480 The address on which to listen, or empty for all addresses.
16481 Defaults to @samp{""}.
16484 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
16485 The port on which to listen.
16488 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
16489 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
16491 Defaults to @samp{#t}.
16496 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
16497 Maximum number of simultaneous client connections per process. Once
16498 this number of connections is received, the next incoming connection
16499 will prompt Dovecot to spawn another process. If set to 0,
16500 @code{default-client-limit} is used instead.
16502 Defaults to @samp{0}.
16506 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
16507 Number of connections to handle before starting a new process.
16508 Typically the only useful values are 0 (unlimited) or 1. 1 is more
16509 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
16510 Defaults to @samp{1}.
16514 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
16515 Maximum number of processes that can exist for this service. If set to
16516 0, @code{default-process-limit} is used instead.
16518 Defaults to @samp{0}.
16522 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
16523 Number of processes to always keep waiting for more connections.
16524 Defaults to @samp{0}.
16527 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
16528 If you set @samp{service-count 0}, you probably need to grow
16530 Defaults to @samp{256000000}.
16535 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
16536 Dict configuration, as created by the @code{dict-configuration}
16539 Available @code{dict-configuration} fields are:
16541 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
16542 A list of key-value pairs that this dict should hold.
16543 Defaults to @samp{()}.
16548 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
16549 A list of passdb configurations, each one created by the
16550 @code{passdb-configuration} constructor.
16552 Available @code{passdb-configuration} fields are:
16554 @deftypevr {@code{passdb-configuration} parameter} string driver
16555 The driver that the passdb should use. Valid values include
16556 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
16558 Defaults to @samp{"pam"}.
16561 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
16562 Space separated list of arguments to the passdb driver.
16563 Defaults to @samp{""}.
16568 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
16569 List of userdb configurations, each one created by the
16570 @code{userdb-configuration} constructor.
16572 Available @code{userdb-configuration} fields are:
16574 @deftypevr {@code{userdb-configuration} parameter} string driver
16575 The driver that the userdb should use. Valid values include
16576 @samp{passwd} and @samp{static}.
16577 Defaults to @samp{"passwd"}.
16580 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
16581 Space separated list of arguments to the userdb driver.
16582 Defaults to @samp{""}.
16585 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
16586 Override fields from passwd.
16587 Defaults to @samp{()}.
16592 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
16593 Plug-in configuration, created by the @code{plugin-configuration}
16597 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
16598 List of namespaces. Each item in the list is created by the
16599 @code{namespace-configuration} constructor.
16601 Available @code{namespace-configuration} fields are:
16603 @deftypevr {@code{namespace-configuration} parameter} string name
16604 Name for this namespace.
16607 @deftypevr {@code{namespace-configuration} parameter} string type
16608 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
16609 Defaults to @samp{"private"}.
16612 @deftypevr {@code{namespace-configuration} parameter} string separator
16613 Hierarchy separator to use. You should use the same separator for
16614 all namespaces or some clients get confused. @samp{/} is usually a good
16615 one. The default however depends on the underlying mail storage
16617 Defaults to @samp{""}.
16620 @deftypevr {@code{namespace-configuration} parameter} string prefix
16621 Prefix required to access this namespace. This needs to be
16622 different for all namespaces. For example @samp{Public/}.
16623 Defaults to @samp{""}.
16626 @deftypevr {@code{namespace-configuration} parameter} string location
16627 Physical location of the mailbox. This is in the same format as
16628 mail_location, which is also the default for it.
16629 Defaults to @samp{""}.
16632 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
16633 There can be only one INBOX, and this setting defines which
16635 Defaults to @samp{#f}.
16638 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
16639 If namespace is hidden, it's not advertised to clients via NAMESPACE
16640 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
16641 useful when converting from another server with different namespaces
16642 which you want to deprecate but still keep working. For example you can
16643 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
16645 Defaults to @samp{#f}.
16648 @deftypevr {@code{namespace-configuration} parameter} boolean list?
16649 Show the mailboxes under this namespace with the LIST command. This
16650 makes the namespace visible for clients that do not support the NAMESPACE
16651 extension. The special @code{children} value lists child mailboxes, but
16652 hides the namespace prefix.
16653 Defaults to @samp{#t}.
16656 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
16657 Namespace handles its own subscriptions. If set to @code{#f}, the
16658 parent namespace handles them. The empty prefix should always have this
16660 Defaults to @samp{#t}.
16663 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
16664 List of predefined mailboxes in this namespace.
16665 Defaults to @samp{()}.
16667 Available @code{mailbox-configuration} fields are:
16669 @deftypevr {@code{mailbox-configuration} parameter} string name
16670 Name for this mailbox.
16673 @deftypevr {@code{mailbox-configuration} parameter} string auto
16674 @samp{create} will automatically create this mailbox.
16675 @samp{subscribe} will both create and subscribe to the mailbox.
16676 Defaults to @samp{"no"}.
16679 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
16680 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
16681 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
16682 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
16683 Defaults to @samp{()}.
16690 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
16691 Base directory where to store runtime data.
16692 Defaults to @samp{"/var/run/dovecot/"}.
16695 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
16696 Greeting message for clients.
16697 Defaults to @samp{"Dovecot ready."}.
16700 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
16701 List of trusted network ranges. Connections from these IPs are
16702 allowed to override their IP addresses and ports (for logging and for
16703 authentication checks). @samp{disable-plaintext-auth} is also ignored
16704 for these networks. Typically you would specify your IMAP proxy servers
16706 Defaults to @samp{()}.
16709 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
16710 List of login access check sockets (e.g.@: tcpwrap).
16711 Defaults to @samp{()}.
16714 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
16715 Show more verbose process titles (in ps). Currently shows user name
16716 and IP address. Useful for seeing who is actually using the IMAP
16717 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
16719 Defaults to @samp{#f}.
16722 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
16723 Should all processes be killed when Dovecot master process shuts down.
16724 Setting this to @code{#f} means that Dovecot can be upgraded without
16725 forcing existing client connections to close (although that could also
16726 be a problem if the upgrade is e.g.@: due to a security fix).
16727 Defaults to @samp{#t}.
16730 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
16731 If non-zero, run mail commands via this many connections to doveadm
16732 server, instead of running them directly in the same process.
16733 Defaults to @samp{0}.
16736 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
16737 UNIX socket or host:port used for connecting to doveadm server.
16738 Defaults to @samp{"doveadm-server"}.
16741 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
16742 List of environment variables that are preserved on Dovecot startup
16743 and passed down to all of its child processes. You can also give
16744 key=value pairs to always set specific settings.
16747 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
16748 Disable LOGIN command and all other plaintext authentications unless
16749 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
16750 matches the local IP (i.e.@: you're connecting from the same computer),
16751 the connection is considered secure and plaintext authentication is
16752 allowed. See also ssl=required setting.
16753 Defaults to @samp{#t}.
16756 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
16757 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
16758 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
16759 for caching to be used.
16760 Defaults to @samp{0}.
16763 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
16764 Time to live for cached data. After TTL expires the cached record
16765 is no longer used, *except* if the main database lookup returns internal
16766 failure. We also try to handle password changes automatically: If
16767 user's previous authentication was successful, but this one wasn't, the
16768 cache isn't used. For now this works only with plaintext
16770 Defaults to @samp{"1 hour"}.
16773 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
16774 TTL for negative hits (user not found, password mismatch).
16775 0 disables caching them completely.
16776 Defaults to @samp{"1 hour"}.
16779 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
16780 List of realms for SASL authentication mechanisms that need them.
16781 You can leave it empty if you don't want to support multiple realms.
16782 Many clients simply use the first one listed here, so keep the default
16784 Defaults to @samp{()}.
16787 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
16788 Default realm/domain to use if none was specified. This is used for
16789 both SASL realms and appending @@domain to username in plaintext
16791 Defaults to @samp{""}.
16794 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
16795 List of allowed characters in username. If the user-given username
16796 contains a character not listed in here, the login automatically fails.
16797 This is just an extra check to make sure user can't exploit any
16798 potential quote escaping vulnerabilities with SQL/LDAP databases. If
16799 you want to allow all characters, set this value to empty.
16800 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
16803 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
16804 Username character translations before it's looked up from
16805 databases. The value contains series of from -> to characters. For
16806 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
16807 translated to @samp{@@}.
16808 Defaults to @samp{""}.
16811 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
16812 Username formatting before it's looked up from databases. You can
16813 use the standard variables here, e.g.@: %Lu would lowercase the username,
16814 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
16815 change the @samp{@@} into @samp{-AT-}. This translation is done after
16816 @samp{auth-username-translation} changes.
16817 Defaults to @samp{"%Lu"}.
16820 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
16821 If you want to allow master users to log in by specifying the master
16822 username within the normal username string (i.e.@: not using SASL
16823 mechanism's support for it), you can specify the separator character
16824 here. The format is then <username><separator><master username>.
16825 UW-IMAP uses @samp{*} as the separator, so that could be a good
16827 Defaults to @samp{""}.
16830 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
16831 Username to use for users logging in with ANONYMOUS SASL
16833 Defaults to @samp{"anonymous"}.
16836 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
16837 Maximum number of dovecot-auth worker processes. They're used to
16838 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
16839 They're automatically created and destroyed as needed.
16840 Defaults to @samp{30}.
16843 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
16844 Host name to use in GSSAPI principal names. The default is to use
16845 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
16846 allow all keytab entries.
16847 Defaults to @samp{""}.
16850 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
16851 Kerberos keytab to use for the GSSAPI mechanism. Will use the
16852 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
16853 need to change the auth service to run as root to be able to read this
16855 Defaults to @samp{""}.
16858 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
16859 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
16860 and @samp{ntlm-auth} helper.
16861 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
16862 Defaults to @samp{#f}.
16865 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
16866 Path for Samba's @samp{ntlm-auth} helper binary.
16867 Defaults to @samp{"/usr/bin/ntlm_auth"}.
16870 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
16871 Time to delay before replying to failed authentications.
16872 Defaults to @samp{"2 secs"}.
16875 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
16876 Require a valid SSL client certificate or the authentication
16878 Defaults to @samp{#f}.
16881 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
16882 Take the username from client's SSL certificate, using
16883 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
16885 Defaults to @samp{#f}.
16888 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
16889 List of wanted authentication mechanisms. Supported mechanisms are:
16890 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
16891 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
16892 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
16893 @samp{disable-plaintext-auth} setting.
16896 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
16897 List of IPs or hostnames to all director servers, including ourself.
16898 Ports can be specified as ip:port. The default port is the same as what
16899 director service's @samp{inet-listener} is using.
16900 Defaults to @samp{()}.
16903 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
16904 List of IPs or hostnames to all backend mail servers. Ranges are
16905 allowed too, like 10.0.0.10-10.0.0.30.
16906 Defaults to @samp{()}.
16909 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
16910 How long to redirect users to a specific server after it no longer
16911 has any connections.
16912 Defaults to @samp{"15 min"}.
16915 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
16916 How the username is translated before being hashed. Useful values
16917 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
16918 are shared within domain.
16919 Defaults to @samp{"%Lu"}.
16922 @deftypevr {@code{dovecot-configuration} parameter} string log-path
16923 Log file to use for error messages. @samp{syslog} logs to syslog,
16924 @samp{/dev/stderr} logs to stderr.
16925 Defaults to @samp{"syslog"}.
16928 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
16929 Log file to use for informational messages. Defaults to
16931 Defaults to @samp{""}.
16934 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
16935 Log file to use for debug messages. Defaults to
16936 @samp{info-log-path}.
16937 Defaults to @samp{""}.
16940 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
16941 Syslog facility to use if you're logging to syslog. Usually if you
16942 don't want to use @samp{mail}, you'll use local0..local7. Also other
16943 standard facilities are supported.
16944 Defaults to @samp{"mail"}.
16947 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
16948 Log unsuccessful authentication attempts and the reasons why they
16950 Defaults to @samp{#f}.
16953 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
16954 In case of password mismatches, log the attempted password. Valid
16955 values are no, plain and sha1. sha1 can be useful for detecting brute
16956 force password attempts vs. user simply trying the same password over
16957 and over again. You can also truncate the value to n chars by appending
16958 ":n" (e.g.@: sha1:6).
16959 Defaults to @samp{"no"}.
16962 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
16963 Even more verbose logging for debugging purposes. Shows for example
16965 Defaults to @samp{#f}.
16968 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
16969 In case of password mismatches, log the passwords and used scheme so
16970 the problem can be debugged. Enabling this also enables
16972 Defaults to @samp{#f}.
16975 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
16976 Enable mail process debugging. This can help you figure out why
16977 Dovecot isn't finding your mails.
16978 Defaults to @samp{#f}.
16981 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
16982 Show protocol level SSL errors.
16983 Defaults to @samp{#f}.
16986 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
16987 Prefix for each line written to log file. % codes are in
16988 strftime(3) format.
16989 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
16992 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
16993 List of elements we want to log. The elements which have a
16994 non-empty variable value are joined together to form a comma-separated
16998 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
16999 Login log format. %s contains @samp{login-log-format-elements}
17000 string, %$ contains the data we want to log.
17001 Defaults to @samp{"%$: %s"}.
17004 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
17005 Log prefix for mail processes. See doc/wiki/Variables.txt for list
17006 of possible variables you can use.
17007 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
17010 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
17011 Format to use for logging mail deliveries. You can use variables:
17014 Delivery status message (e.g.@: @samp{saved to INBOX})
17026 Defaults to @samp{"msgid=%m: %$"}.
17029 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
17030 Location for users' mailboxes. The default is empty, which means
17031 that Dovecot tries to find the mailboxes automatically. This won't work
17032 if the user doesn't yet have any mail, so you should explicitly tell
17033 Dovecot the full location.
17035 If you're using mbox, giving a path to the INBOX
17036 file (e.g.@: /var/mail/%u) isn't enough. You'll also need to tell Dovecot
17037 where the other mailboxes are kept. This is called the "root mail
17038 directory", and it must be the first path given in the
17039 @samp{mail-location} setting.
17041 There are a few special variables you can use, eg.:
17047 user part in user@@domain, same as %u if there's no domain
17049 domain part in user@@domain, empty if there's no domain
17054 See doc/wiki/Variables.txt for full list. Some examples:
17056 @item maildir:~/Maildir
17057 @item mbox:~/mail:INBOX=/var/mail/%u
17058 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
17060 Defaults to @samp{""}.
17063 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
17064 System user and group used to access mails. If you use multiple,
17065 userdb can override these by returning uid or gid fields. You can use
17066 either numbers or names. <doc/wiki/UserIds.txt>.
17067 Defaults to @samp{""}.
17070 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
17072 Defaults to @samp{""}.
17075 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
17076 Group to enable temporarily for privileged operations. Currently
17077 this is used only with INBOX when either its initial creation or
17078 dotlocking fails. Typically this is set to "mail" to give access to
17080 Defaults to @samp{""}.
17083 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
17084 Grant access to these supplementary groups for mail processes.
17085 Typically these are used to set up access to shared mailboxes. Note
17086 that it may be dangerous to set these if users can create
17087 symlinks (e.g.@: if "mail" group is set here, ln -s /var/mail ~/mail/var
17088 could allow a user to delete others' mailboxes, or ln -s
17089 /secret/shared/box ~/mail/mybox would allow reading it).
17090 Defaults to @samp{""}.
17093 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
17094 Allow full file system access to clients. There's no access checks
17095 other than what the operating system does for the active UID/GID. It
17096 works with both maildir and mboxes, allowing you to prefix mailboxes
17097 names with e.g.@: /path/ or ~user/.
17098 Defaults to @samp{#f}.
17101 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
17102 Don't use mmap() at all. This is required if you store indexes to
17103 shared file systems (NFS or clustered file system).
17104 Defaults to @samp{#f}.
17107 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
17108 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
17109 supports @samp{O_EXCL} since version 3, so this should be safe to use
17110 nowadays by default.
17111 Defaults to @samp{#t}.
17114 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
17115 When to use fsync() or fdatasync() calls:
17118 Whenever necessary to avoid losing important data
17120 Useful with e.g.@: NFS when write()s are delayed
17122 Never use it (best performance, but crashes can lose data).
17124 Defaults to @samp{"optimized"}.
17127 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
17128 Mail storage exists in NFS. Set this to yes to make Dovecot flush
17129 NFS caches whenever needed. If you're using only a single mail server
17131 Defaults to @samp{#f}.
17134 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
17135 Mail index files also exist in NFS. Setting this to yes requires
17136 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
17137 Defaults to @samp{#f}.
17140 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
17141 Locking method for index files. Alternatives are fcntl, flock and
17142 dotlock. Dotlocking uses some tricks which may create more disk I/O
17143 than other locking methods. NFS users: flock doesn't work, remember to
17144 change @samp{mmap-disable}.
17145 Defaults to @samp{"fcntl"}.
17148 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
17149 Directory in which LDA/LMTP temporarily stores incoming mails >128
17151 Defaults to @samp{"/tmp"}.
17154 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
17155 Valid UID range for users. This is mostly to make sure that users can't
17156 log in as daemons or other system users. Note that denying root logins is
17157 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
17159 Defaults to @samp{500}.
17162 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
17164 Defaults to @samp{0}.
17167 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
17168 Valid GID range for users. Users having non-valid GID as primary group ID
17169 aren't allowed to log in. If user belongs to supplementary groups with
17170 non-valid GIDs, those groups are not set.
17171 Defaults to @samp{1}.
17174 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
17176 Defaults to @samp{0}.
17179 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
17180 Maximum allowed length for mail keyword name. It's only forced when
17181 trying to create new keywords.
17182 Defaults to @samp{50}.
17185 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
17186 List of directories under which chrooting is allowed for mail
17187 processes (i.e.@: /var/mail will allow chrooting to /var/mail/foo/bar
17188 too). This setting doesn't affect @samp{login-chroot}
17189 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
17190 "/./" in home dirs are ignored. WARNING: Never add directories here
17191 which local users can modify, that may lead to root exploit. Usually
17192 this should be done only if you don't allow shell access for users.
17193 <doc/wiki/Chrooting.txt>.
17194 Defaults to @samp{()}.
17197 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
17198 Default chroot directory for mail processes. This can be overridden
17199 for specific users in user database by giving /./ in user's home
17200 directory (e.g.@: /home/./user chroots into /home). Note that usually
17201 there is no real need to do chrooting, Dovecot doesn't allow users to
17202 access files outside their mail directory anyway. If your home
17203 directories are prefixed with the chroot directory, append "/."@: to
17204 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
17205 Defaults to @samp{""}.
17208 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
17209 UNIX socket path to master authentication server to find users.
17210 This is used by imap (for shared users) and lda.
17211 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
17214 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
17215 Directory where to look up mail plugins.
17216 Defaults to @samp{"/usr/lib/dovecot"}.
17219 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
17220 List of plugins to load for all services. Plugins specific to IMAP,
17221 LDA, etc.@: are added to this list in their own .conf files.
17222 Defaults to @samp{()}.
17225 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
17226 The minimum number of mails in a mailbox before updates are done to
17227 cache file. This allows optimizing Dovecot's behavior to do less disk
17228 writes at the cost of more disk reads.
17229 Defaults to @samp{0}.
17232 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
17233 When IDLE command is running, mailbox is checked once in a while to
17234 see if there are any new mails or other changes. This setting defines
17235 the minimum time to wait between those checks. Dovecot can also use
17236 dnotify, inotify and kqueue to find out immediately when changes
17238 Defaults to @samp{"30 secs"}.
17241 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
17242 Save mails with CR+LF instead of plain LF. This makes sending those
17243 mails take less CPU, especially with sendfile() syscall with Linux and
17244 FreeBSD. But it also creates a bit more disk I/O which may just make it
17245 slower. Also note that if other software reads the mboxes/maildirs,
17246 they may handle the extra CRs wrong and cause problems.
17247 Defaults to @samp{#f}.
17250 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
17251 By default LIST command returns all entries in maildir beginning
17252 with a dot. Enabling this option makes Dovecot return only entries
17253 which are directories. This is done by stat()ing each entry, so it
17254 causes more disk I/O.
17255 (For systems setting struct @samp{dirent->d_type} this check is free
17256 and it's done always regardless of this setting).
17257 Defaults to @samp{#f}.
17260 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
17261 When copying a message, do it with hard links whenever possible.
17262 This makes the performance much better, and it's unlikely to have any
17264 Defaults to @samp{#t}.
17267 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
17268 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
17269 directory only when its mtime changes unexpectedly or when we can't find
17270 the mail otherwise.
17271 Defaults to @samp{#f}.
17274 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
17275 Which locking methods to use for locking mbox. There are four
17280 Create <mailbox>.lock file. This is the oldest and most NFS-safe
17281 solution. If you want to use /var/mail/ like directory, the users will
17282 need write access to that directory.
17284 Same as dotlock, but if it fails because of permissions or because there
17285 isn't enough disk space, just skip it.
17287 Use this if possible. Works with NFS too if lockd is used.
17289 May not exist in all systems. Doesn't work with NFS.
17291 May not exist in all systems. Doesn't work with NFS.
17294 You can use multiple locking methods; if you do the order they're declared
17295 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
17296 locking methods as well. Some operating systems don't allow using some of
17297 them simultaneously.
17300 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
17304 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
17305 Maximum time to wait for lock (all of them) before aborting.
17306 Defaults to @samp{"5 mins"}.
17309 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
17310 If dotlock exists but the mailbox isn't modified in any way,
17311 override the lock file after this much time.
17312 Defaults to @samp{"2 mins"}.
17315 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
17316 When mbox changes unexpectedly we have to fully read it to find out
17317 what changed. If the mbox is large this can take a long time. Since
17318 the change is usually just a newly appended mail, it'd be faster to
17319 simply read the new mails. If this setting is enabled, Dovecot does
17320 this but still safely fallbacks to re-reading the whole mbox file
17321 whenever something in mbox isn't how it's expected to be. The only real
17322 downside to this setting is that if some other MUA changes message
17323 flags, Dovecot doesn't notice it immediately. Note that a full sync is
17324 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
17325 Defaults to @samp{#t}.
17328 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
17329 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
17330 EXAMINE, EXPUNGE or CHECK commands. If this is set,
17331 @samp{mbox-dirty-syncs} is ignored.
17332 Defaults to @samp{#f}.
17335 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
17336 Delay writing mbox headers until doing a full write sync (EXPUNGE
17337 and CHECK commands and when closing the mailbox). This is especially
17338 useful for POP3 where clients often delete all mails. The downside is
17339 that our changes aren't immediately visible to other MUAs.
17340 Defaults to @samp{#t}.
17343 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
17344 If mbox size is smaller than this (e.g.@: 100k), don't write index
17345 files. If an index file already exists it's still read, just not
17347 Defaults to @samp{0}.
17350 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
17351 Maximum dbox file size until it's rotated.
17352 Defaults to @samp{10000000}.
17355 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
17356 Maximum dbox file age until it's rotated. Typically in days. Day
17357 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
17359 Defaults to @samp{"1d"}.
17362 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
17363 When creating new mdbox files, immediately preallocate their size to
17364 @samp{mdbox-rotate-size}. This setting currently works only in Linux
17365 with some file systems (ext4, xfs).
17366 Defaults to @samp{#f}.
17369 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
17370 sdbox and mdbox support saving mail attachments to external files,
17371 which also allows single instance storage for them. Other backends
17372 don't support this for now.
17374 WARNING: This feature hasn't been tested much yet. Use at your own risk.
17376 Directory root where to store mail attachments. Disabled, if empty.
17377 Defaults to @samp{""}.
17380 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
17381 Attachments smaller than this aren't saved externally. It's also
17382 possible to write a plugin to disable saving specific attachments
17384 Defaults to @samp{128000}.
17387 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
17388 File system backend to use for saving attachments:
17391 No SiS done by Dovecot (but this might help FS's own deduplication)
17393 SiS with immediate byte-by-byte comparison during saving
17394 @item sis-queue posix
17395 SiS with delayed comparison and deduplication.
17397 Defaults to @samp{"sis posix"}.
17400 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
17401 Hash format to use in attachment filenames. You can add any text and
17402 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
17403 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
17404 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
17405 Defaults to @samp{"%@{sha1@}"}.
17408 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
17410 Defaults to @samp{100}.
17413 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
17415 Defaults to @samp{1000}.
17418 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
17419 Default VSZ (virtual memory size) limit for service processes.
17420 This is mainly intended to catch and kill processes that leak memory
17421 before they eat up everything.
17422 Defaults to @samp{256000000}.
17425 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
17426 Login user is internally used by login processes. This is the most
17427 untrusted user in Dovecot system. It shouldn't have access to anything
17429 Defaults to @samp{"dovenull"}.
17432 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
17433 Internal user is used by unprivileged processes. It should be
17434 separate from login user, so that login processes can't disturb other
17436 Defaults to @samp{"dovecot"}.
17439 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
17440 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
17441 Defaults to @samp{"required"}.
17444 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
17445 PEM encoded X.509 SSL/TLS certificate (public key).
17446 Defaults to @samp{"</etc/dovecot/default.pem"}.
17449 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
17450 PEM encoded SSL/TLS private key. The key is opened before
17451 dropping root privileges, so keep the key file unreadable by anyone but
17453 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
17456 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
17457 If key file is password protected, give the password here.
17458 Alternatively give it when starting dovecot with -p parameter. Since
17459 this file is often world-readable, you may want to place this setting
17460 instead to a different.
17461 Defaults to @samp{""}.
17464 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
17465 PEM encoded trusted certificate authority. Set this only if you
17466 intend to use @samp{ssl-verify-client-cert? #t}. The file should
17467 contain the CA certificate(s) followed by the matching
17468 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
17469 Defaults to @samp{""}.
17472 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
17473 Require that CRL check succeeds for client certificates.
17474 Defaults to @samp{#t}.
17477 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
17478 Request client to send a certificate. If you also want to require
17479 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
17480 Defaults to @samp{#f}.
17483 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
17484 Which field from certificate to use for username. commonName and
17485 x500UniqueIdentifier are the usual choices. You'll also need to set
17486 @samp{auth-ssl-username-from-cert? #t}.
17487 Defaults to @samp{"commonName"}.
17490 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
17491 Minimum SSL protocol version to accept.
17492 Defaults to @samp{"TLSv1"}.
17495 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
17496 SSL ciphers to use.
17497 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
17500 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
17501 SSL crypto device to use, for valid values run "openssl engine".
17502 Defaults to @samp{""}.
17505 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
17506 Address to use when sending rejection mails.
17507 %d expands to recipient domain.
17508 Defaults to @samp{"postmaster@@%d"}.
17511 @deftypevr {@code{dovecot-configuration} parameter} string hostname
17512 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
17513 and in LMTP replies. Default is the system's real hostname@@domain.
17514 Defaults to @samp{""}.
17517 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
17518 If user is over quota, return with temporary failure instead of
17520 Defaults to @samp{#f}.
17523 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
17524 Binary to use for sending mails.
17525 Defaults to @samp{"/usr/sbin/sendmail"}.
17528 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
17529 If non-empty, send mails via this SMTP host[:port] instead of
17531 Defaults to @samp{""}.
17534 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
17535 Subject: header to use for rejection mails. You can use the same
17536 variables as for @samp{rejection-reason} below.
17537 Defaults to @samp{"Rejected: %s"}.
17540 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
17541 Human readable error message for rejection mails. You can use
17554 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
17557 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
17558 Delimiter character between local-part and detail in email
17560 Defaults to @samp{"+"}.
17563 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
17564 Header where the original recipient address (SMTP's RCPT TO:
17565 address) is taken from if not available elsewhere. With dovecot-lda -a
17566 parameter overrides this. A commonly used header for this is
17568 Defaults to @samp{""}.
17571 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
17572 Should saving a mail to a nonexistent mailbox automatically create
17574 Defaults to @samp{#f}.
17577 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
17578 Should automatically created mailboxes be also automatically
17580 Defaults to @samp{#f}.
17583 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
17584 Maximum IMAP command line length. Some clients generate very long
17585 command lines with huge mailboxes, so you may need to raise this if you
17586 get "Too long argument" or "IMAP command line too large" errors
17588 Defaults to @samp{64000}.
17591 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
17592 IMAP logout format string:
17595 total number of bytes read from client
17597 total number of bytes sent to client.
17599 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
17600 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@}"}.
17603 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
17604 Override the IMAP CAPABILITY response. If the value begins with '+',
17605 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
17606 Defaults to @samp{""}.
17609 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
17610 How long to wait between "OK Still here" notifications when client
17612 Defaults to @samp{"2 mins"}.
17615 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
17616 ID field names and values to send to clients. Using * as the value
17617 makes Dovecot use the default value. The following fields have default
17618 values currently: name, version, os, os-version, support-url,
17620 Defaults to @samp{""}.
17623 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
17624 ID fields sent by client to log. * means everything.
17625 Defaults to @samp{""}.
17628 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
17629 Workarounds for various client bugs:
17632 @item delay-newmail
17633 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
17634 CHECK commands. Some clients ignore them otherwise, for example OSX
17635 Mail (<v2.1). Outlook Express breaks more badly though, without this it
17636 may show user "Message no longer in server" errors. Note that OE6
17637 still breaks even with this workaround if synchronization is set to
17640 @item tb-extra-mailbox-sep
17641 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
17642 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
17643 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
17645 @item tb-lsub-flags
17646 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
17647 This makes Thunderbird realize they aren't selectable and show them
17648 greyed out, instead of only later giving "not selectable" popup error.
17650 Defaults to @samp{()}.
17653 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
17654 Host allowed in URLAUTH URLs sent by client. "*" allows all.
17655 Defaults to @samp{""}.
17659 Whew! Lots of configuration options. The nice thing about it though is
17660 that Guix has a complete interface to Dovecot's configuration
17661 language. This allows not only a nice way to declare configurations,
17662 but also offers reflective capabilities as well: users can write code to
17663 inspect and transform configurations from within Scheme.
17665 However, it could be that you just want to get a @code{dovecot.conf} up
17666 and running. In that case, you can pass an
17667 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
17668 @code{dovecot-service}. As its name indicates, an opaque configuration
17669 does not have easy reflective capabilities.
17671 Available @code{opaque-dovecot-configuration} fields are:
17673 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
17674 The dovecot package.
17677 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
17678 The contents of the @code{dovecot.conf}, as a string.
17681 For example, if your @code{dovecot.conf} is just the empty string, you
17682 could instantiate a dovecot service like this:
17685 (dovecot-service #:config
17686 (opaque-dovecot-configuration
17690 @subsubheading OpenSMTPD Service
17692 @deffn {Scheme Variable} opensmtpd-service-type
17693 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
17694 service, whose value should be an @code{opensmtpd-configuration} object
17695 as in this example:
17698 (service opensmtpd-service-type
17699 (opensmtpd-configuration
17700 (config-file (local-file "./my-smtpd.conf"))))
17704 @deftp {Data Type} opensmtpd-configuration
17705 Data type representing the configuration of opensmtpd.
17708 @item @code{package} (default: @var{opensmtpd})
17709 Package object of the OpenSMTPD SMTP server.
17711 @item @code{config-file} (default: @code{%default-opensmtpd-file})
17712 File-like object of the OpenSMTPD configuration file to use. By default
17713 it listens on the loopback network interface, and allows for mail from
17714 users and daemons on the local machine, as well as permitting email to
17715 remote servers. Run @command{man smtpd.conf} for more information.
17720 @subsubheading Exim Service
17722 @cindex mail transfer agent (MTA)
17723 @cindex MTA (mail transfer agent)
17726 @deffn {Scheme Variable} exim-service-type
17727 This is the type of the @uref{https://exim.org, Exim} mail transfer
17728 agent (MTA), whose value should be an @code{exim-configuration} object
17729 as in this example:
17732 (service exim-service-type
17733 (exim-configuration
17734 (config-file (local-file "./my-exim.conf"))))
17738 In order to use an @code{exim-service-type} service you must also have a
17739 @code{mail-aliases-service-type} service present in your
17740 @code{operating-system} (even if it has no aliases).
17742 @deftp {Data Type} exim-configuration
17743 Data type representing the configuration of exim.
17746 @item @code{package} (default: @var{exim})
17747 Package object of the Exim server.
17749 @item @code{config-file} (default: @code{#f})
17750 File-like object of the Exim configuration file to use. If its value is
17751 @code{#f} then use the default configuration file from the package
17752 provided in @code{package}. The resulting configuration file is loaded
17753 after setting the @code{exim_user} and @code{exim_group} configuration
17759 @subsubheading Getmail service
17764 @deffn {Scheme Variable} getmail-service-type
17765 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
17766 mail retriever, whose value should be an @code{getmail-configuration}.
17769 Available @code{getmail-configuration} fields are:
17771 @deftypevr {@code{getmail-configuration} parameter} symbol name
17772 A symbol to identify the getmail service.
17774 Defaults to @samp{"unset"}.
17778 @deftypevr {@code{getmail-configuration} parameter} package package
17779 The getmail package to use.
17783 @deftypevr {@code{getmail-configuration} parameter} string user
17784 The user to run getmail as.
17786 Defaults to @samp{"getmail"}.
17790 @deftypevr {@code{getmail-configuration} parameter} string group
17791 The group to run getmail as.
17793 Defaults to @samp{"getmail"}.
17797 @deftypevr {@code{getmail-configuration} parameter} string directory
17798 The getmail directory to use.
17800 Defaults to @samp{"/var/lib/getmail/default"}.
17804 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
17805 The getmail configuration file to use.
17807 Available @code{getmail-configuration-file} fields are:
17809 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
17810 What mail account to retrieve mail from, and how to access that account.
17812 Available @code{getmail-retriever-configuration} fields are:
17814 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
17815 The type of mail retriever to use. Valid values include @samp{passwd}
17818 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
17822 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
17823 Username to login to the mail server with.
17825 Defaults to @samp{unset}.
17829 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
17830 Username to login to the mail server with.
17832 Defaults to @samp{unset}.
17836 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
17837 Port number to connect to.
17839 Defaults to @samp{#f}.
17843 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
17844 Override fields from passwd.
17846 Defaults to @samp{""}.
17850 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
17851 Override fields from passwd.
17853 Defaults to @samp{()}.
17857 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
17858 PEM-formatted key file to use for the TLS negotiation.
17860 Defaults to @samp{""}.
17864 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
17865 PEM-formatted certificate file to use for the TLS negotiation.
17867 Defaults to @samp{""}.
17871 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
17872 CA certificates to use.
17874 Defaults to @samp{""}.
17878 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
17879 Extra retriever parameters.
17881 Defaults to @samp{()}.
17887 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
17888 What to do with retrieved messages.
17890 Available @code{getmail-destination-configuration} fields are:
17892 @deftypevr {@code{getmail-destination-configuration} parameter} string type
17893 The type of mail destination. Valid values include @samp{Maildir},
17894 @samp{Mboxrd} and @samp{MDA_external}.
17896 Defaults to @samp{unset}.
17900 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
17901 The path option for the mail destination. The behaviour depends on the
17904 Defaults to @samp{""}.
17908 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
17909 Extra destination parameters
17911 Defaults to @samp{()}.
17917 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
17920 Available @code{getmail-options-configuration} fields are:
17922 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
17923 If set to @samp{0}, getmail will only print warnings and errors. A
17924 value of @samp{1} means that messages will be printed about retrieving
17925 and deleting messages. If set to @samp{2}, getmail will print messages
17926 about each of it's actions.
17928 Defaults to @samp{1}.
17932 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
17933 If true, getmail will retrieve all available messages. Otherwise it
17934 will only retrieve messages it hasn't seen previously.
17936 Defaults to @samp{#t}.
17940 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
17941 If set to true, messages will be deleted from the server after
17942 retrieving and successfully delivering them. Otherwise, messages will
17943 be left on the server.
17945 Defaults to @samp{#f}.
17949 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
17950 Getmail will delete messages this number of days after seeing them, if
17951 they have been delivered. This means messages will be left on the
17952 server this number of days after delivering them. A value of @samp{0}
17953 disabled this feature.
17955 Defaults to @samp{0}.
17959 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
17960 Delete messages larger than this of bytes after retrieving them, even if
17961 the delete and delete-after options are disabled. A value of @samp{0}
17962 disables this feature.
17964 Defaults to @samp{0}.
17968 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
17969 Retrieve messages totalling up to this number of bytes before closing
17970 the session with the server. A value of @samp{0} disables this feature.
17972 Defaults to @samp{0}.
17976 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
17977 Don't retrieve messages larger than this number of bytes. A value of
17978 @samp{0} disables this feature.
17980 Defaults to @samp{0}.
17984 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
17985 If true, getmail will add a Delivered-To header to messages.
17987 Defaults to @samp{#t}.
17991 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
17992 If set, getmail adds a Received header to the messages.
17994 Defaults to @samp{#t}.
17998 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
17999 Getmail will record a log of its actions to the named file. A value of
18000 @samp{""} disables this feature.
18002 Defaults to @samp{""}.
18006 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
18007 If true, getmail will record a log of its actions using the system
18010 Defaults to @samp{#f}.
18014 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
18015 If true, getmail will log information about messages not retrieved and
18016 the reason for not retrieving them, as well as starting and ending
18019 Defaults to @samp{#f}.
18023 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
18024 Extra options to include.
18026 Defaults to @samp{()}.
18034 @deftypevr {@code{getmail-configuration} parameter} list idle
18035 A list of mailboxes that getmail should wait on the server for new mail
18036 notifications. This depends on the server supporting the IDLE
18039 Defaults to @samp{()}.
18043 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
18044 Environment variables to set for getmail.
18046 Defaults to @samp{()}.
18050 @subsubheading Mail Aliases Service
18052 @cindex email aliases
18053 @cindex aliases, for email addresses
18055 @deffn {Scheme Variable} mail-aliases-service-type
18056 This is the type of the service which provides @code{/etc/aliases},
18057 specifying how to deliver mail to users on this system.
18060 (service mail-aliases-service-type
18061 '(("postmaster" "bob")
18062 ("bob" "bob@@example.com" "bob@@example2.com")))
18066 The configuration for a @code{mail-aliases-service-type} service is an
18067 association list denoting how to deliver mail that comes to this
18068 system. Each entry is of the form @code{(alias addresses ...)}, with
18069 @code{alias} specifying the local alias and @code{addresses} specifying
18070 where to deliver this user's mail.
18072 The aliases aren't required to exist as users on the local system. In
18073 the above example, there doesn't need to be a @code{postmaster} entry in
18074 the @code{operating-system}'s @code{user-accounts} in order to deliver
18075 the @code{postmaster} mail to @code{bob} (which subsequently would
18076 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
18078 @subsubheading GNU Mailutils IMAP4 Daemon
18079 @cindex GNU Mailutils IMAP4 Daemon
18081 @deffn {Scheme Variable} imap4d-service-type
18082 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
18083 mailutils, GNU Mailutils Manual}), whose value should be an
18084 @code{imap4d-configuration} object as in this example:
18087 (service imap4d-service-type
18088 (imap4d-configuration
18089 (config-file (local-file "imap4d.conf"))))
18093 @deftp {Data Type} imap4d-configuration
18094 Data type representing the configuration of @command{imap4d}.
18097 @item @code{package} (default: @code{mailutils})
18098 The package that provides @command{imap4d}.
18100 @item @code{config-file} (default: @code{%default-imap4d-config-file})
18101 File-like object of the configuration file to use, by default it will listen
18102 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
18103 Mailutils Manual}, for details.
18108 @node Messaging Services
18109 @subsection Messaging Services
18114 The @code{(gnu services messaging)} module provides Guix service
18115 definitions for messaging services: currently only Prosody is supported.
18117 @subsubheading Prosody Service
18119 @deffn {Scheme Variable} prosody-service-type
18120 This is the type for the @uref{https://prosody.im, Prosody XMPP
18121 communication server}. Its value must be a @code{prosody-configuration}
18122 record as in this example:
18125 (service prosody-service-type
18126 (prosody-configuration
18127 (modules-enabled (cons "groups" "mam" %default-modules-enabled))
18130 (int-component-configuration
18131 (hostname "conference.example.net")
18133 (mod-muc (mod-muc-configuration)))))
18136 (virtualhost-configuration
18137 (domain "example.net"))))))
18140 See below for details about @code{prosody-configuration}.
18144 By default, Prosody does not need much configuration. Only one
18145 @code{virtualhosts} field is needed: it specifies the domain you wish
18148 You can perform various sanity checks on the generated configuration
18149 with the @code{prosodyctl check} command.
18151 Prosodyctl will also help you to import certificates from the
18152 @code{letsencrypt} directory so that the @code{prosody} user can access
18153 them. See @url{https://prosody.im/doc/letsencrypt}.
18156 prosodyctl --root cert import /etc/letsencrypt/live
18159 The available configuration parameters follow. Each parameter
18160 definition is preceded by its type; for example, @samp{string-list foo}
18161 indicates that the @code{foo} parameter should be specified as a list of
18162 strings. Types starting with @code{maybe-} denote parameters that won't
18163 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
18165 There is also a way to specify the configuration as a string, if you
18166 have an old @code{prosody.cfg.lua} file that you want to port over from
18167 some other system; see the end for more details.
18169 The @code{file-object} type designates either a file-like object
18170 (@pxref{G-Expressions, file-like objects}) or a file name.
18172 @c The following documentation was initially generated by
18173 @c (generate-documentation) in (gnu services messaging). Manually maintained
18174 @c documentation is better, so we shouldn't hesitate to edit below as
18175 @c needed. However if the change you want to make to this documentation
18176 @c can be done in an automated way, it's probably easier to change
18177 @c (generate-documentation) than to make it below and have to deal with
18178 @c the churn as Prosody updates.
18180 Available @code{prosody-configuration} fields are:
18182 @deftypevr {@code{prosody-configuration} parameter} package prosody
18183 The Prosody package.
18186 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
18187 Location of the Prosody data storage directory. See
18188 @url{https://prosody.im/doc/configure}.
18189 Defaults to @samp{"/var/lib/prosody"}.
18192 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
18193 Additional plugin directories. They are searched in all the specified
18194 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
18195 Defaults to @samp{()}.
18198 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
18199 Every virtual host and component needs a certificate so that clients and
18200 servers can securely verify its identity. Prosody will automatically load
18201 certificates/keys from the directory specified here.
18202 Defaults to @samp{"/etc/prosody/certs"}.
18205 @deftypevr {@code{prosody-configuration} parameter} string-list admins
18206 This is a list of accounts that are admins for the server. Note that you
18207 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
18208 @url{https://prosody.im/doc/creating_accounts}.
18209 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
18210 Defaults to @samp{()}.
18213 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
18214 Enable use of libevent for better performance under high load. See
18215 @url{https://prosody.im/doc/libevent}.
18216 Defaults to @samp{#f}.
18219 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
18220 This is the list of modules Prosody will load on startup. It looks for
18221 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
18222 Documentation on modules can be found at:
18223 @url{https://prosody.im/doc/modules}.
18224 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
18227 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
18228 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
18229 should you want to disable them then add them to this list.
18230 Defaults to @samp{()}.
18233 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
18234 Path to a text file where the shared groups are defined. If this path is
18235 empty then @samp{mod_groups} does nothing. See
18236 @url{https://prosody.im/doc/modules/mod_groups}.
18237 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
18240 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
18241 Disable account creation by default, for security. See
18242 @url{https://prosody.im/doc/creating_accounts}.
18243 Defaults to @samp{#f}.
18246 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
18247 These are the SSL/TLS-related settings. Most of them are disabled so to
18248 use Prosody's defaults. If you do not completely understand these options, do
18249 not add them to your config, it is easy to lower the security of your server
18250 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
18252 Available @code{ssl-configuration} fields are:
18254 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
18255 This determines what handshake to use.
18258 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
18259 Path to your private key file.
18262 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
18263 Path to your certificate file.
18266 @deftypevr {@code{ssl-configuration} parameter} file-object capath
18267 Path to directory containing root certificates that you wish Prosody to
18268 trust when verifying the certificates of remote servers.
18269 Defaults to @samp{"/etc/ssl/certs"}.
18272 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
18273 Path to a file containing root certificates that you wish Prosody to trust.
18274 Similar to @code{capath} but with all certificates concatenated together.
18277 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
18278 A list of verification options (these mostly map to OpenSSL's
18279 @code{set_verify()} flags).
18282 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
18283 A list of general options relating to SSL/TLS. These map to OpenSSL's
18284 @code{set_options()}. For a full list of options available in LuaSec, see the
18288 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
18289 How long a chain of certificate authorities to check when looking for a
18290 trusted root certificate.
18293 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
18294 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
18295 clients, and in what order.
18298 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
18299 A path to a file containing parameters for Diffie-Hellman key exchange. You
18300 can create such a file with:
18301 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
18304 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
18305 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
18306 @samp{"secp384r1"}.
18309 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
18310 A list of "extra" verification options.
18313 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
18314 Password for encrypted private keys.
18319 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
18320 Whether to force all client-to-server connections to be encrypted or not.
18321 See @url{https://prosody.im/doc/modules/mod_tls}.
18322 Defaults to @samp{#f}.
18325 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
18326 Set of mechanisms that will never be offered. See
18327 @url{https://prosody.im/doc/modules/mod_saslauth}.
18328 Defaults to @samp{("DIGEST-MD5")}.
18331 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
18332 Whether to force all server-to-server connections to be encrypted or not.
18333 See @url{https://prosody.im/doc/modules/mod_tls}.
18334 Defaults to @samp{#f}.
18337 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
18338 Whether to require encryption and certificate authentication. This
18339 provides ideal security, but requires servers you communicate with to support
18340 encryption AND present valid, trusted certificates. See
18341 @url{https://prosody.im/doc/s2s#security}.
18342 Defaults to @samp{#f}.
18345 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
18346 Many servers don't support encryption or have invalid or self-signed
18347 certificates. You can list domains here that will not be required to
18348 authenticate using certificates. They will be authenticated using DNS. See
18349 @url{https://prosody.im/doc/s2s#security}.
18350 Defaults to @samp{()}.
18353 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
18354 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
18355 valid certificates for some domains by specifying a list here. See
18356 @url{https://prosody.im/doc/s2s#security}.
18357 Defaults to @samp{()}.
18360 @deftypevr {@code{prosody-configuration} parameter} string authentication
18361 Select the authentication backend to use. The default provider stores
18362 passwords in plaintext and uses Prosody's configured data storage to store the
18363 authentication data. If you do not trust your server please see
18364 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
18365 about using the hashed backend. See also
18366 @url{https://prosody.im/doc/authentication}
18367 Defaults to @samp{"internal_plain"}.
18370 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
18371 Set logging options. Advanced logging configuration is not yet supported
18372 by the Prosody service. See @url{https://prosody.im/doc/logging}.
18373 Defaults to @samp{"*syslog"}.
18376 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
18377 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
18378 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
18381 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
18382 Maximum allowed size of the HTTP body (in bytes).
18385 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
18386 Some modules expose their own URL in various ways. This URL is built
18387 from the protocol, host and port used. If Prosody sits behind a proxy, the
18388 public URL will be @code{http-external-url} instead. See
18389 @url{https://prosody.im/doc/http#external_url}.
18392 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
18393 A host in Prosody is a domain on which user accounts can be created. For
18394 example if you want your users to have addresses like
18395 @samp{"john.smith@@example.com"} then you need to add a host
18396 @samp{"example.com"}. All options in this list will apply only to this host.
18398 Note: the name "virtual" host is used in configuration to avoid confusion with
18399 the actual physical host that Prosody is installed on. A single Prosody
18400 instance can serve many domains, each one defined as a VirtualHost entry in
18401 Prosody's configuration. Conversely a server that hosts a single domain would
18402 have just one VirtualHost entry.
18404 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
18406 Available @code{virtualhost-configuration} fields are:
18408 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:
18409 @deftypevr {@code{virtualhost-configuration} parameter} string domain
18410 Domain you wish Prosody to serve.
18415 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
18416 Components are extra services on a server which are available to clients,
18417 usually on a subdomain of the main server (such as
18418 @samp{"mycomponent.example.com"}). Example components might be chatroom
18419 servers, user directories, or gateways to other protocols.
18421 Internal components are implemented with Prosody-specific plugins. To add an
18422 internal component, you simply fill the hostname field, and the plugin you wish
18423 to use for the component.
18425 See @url{https://prosody.im/doc/components}.
18426 Defaults to @samp{()}.
18428 Available @code{int-component-configuration} fields are:
18430 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:
18431 @deftypevr {@code{int-component-configuration} parameter} string hostname
18432 Hostname of the component.
18435 @deftypevr {@code{int-component-configuration} parameter} string plugin
18436 Plugin you wish to use for the component.
18439 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
18440 Multi-user chat (MUC) is Prosody's module for allowing you to create
18441 hosted chatrooms/conferences for XMPP users.
18443 General information on setting up and using multi-user chatrooms can be found
18444 in the "Chatrooms" documentation (@url{https://prosody.im/doc/chatrooms}),
18445 which you should read if you are new to XMPP chatrooms.
18447 See also @url{https://prosody.im/doc/modules/mod_muc}.
18449 Available @code{mod-muc-configuration} fields are:
18451 @deftypevr {@code{mod-muc-configuration} parameter} string name
18452 The name to return in service discovery responses.
18453 Defaults to @samp{"Prosody Chatrooms"}.
18456 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
18457 If @samp{#t}, this will only allow admins to create new chatrooms.
18458 Otherwise anyone can create a room. The value @samp{"local"} restricts room
18459 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
18460 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
18461 restricts to service administrators only.
18462 Defaults to @samp{#f}.
18465 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
18466 Maximum number of history messages that will be sent to the member that has
18467 just joined the room.
18468 Defaults to @samp{20}.
18475 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
18476 External components use XEP-0114, which most standalone components
18477 support. To add an external component, you simply fill the hostname field. See
18478 @url{https://prosody.im/doc/components}.
18479 Defaults to @samp{()}.
18481 Available @code{ext-component-configuration} fields are:
18483 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:
18484 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
18485 Password which the component will use to log in.
18488 @deftypevr {@code{ext-component-configuration} parameter} string hostname
18489 Hostname of the component.
18494 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
18495 Port(s) Prosody listens on for component connections.
18496 Defaults to @samp{(5347)}.
18499 @deftypevr {@code{prosody-configuration} parameter} string component-interface
18500 Interface Prosody listens on for component connections.
18501 Defaults to @samp{"127.0.0.1"}.
18504 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
18505 Raw content that will be added to the configuration file.
18508 It could be that you just want to get a @code{prosody.cfg.lua}
18509 up and running. In that case, you can pass an
18510 @code{opaque-prosody-configuration} record as the value of
18511 @code{prosody-service-type}. As its name indicates, an opaque configuration
18512 does not have easy reflective capabilities.
18513 Available @code{opaque-prosody-configuration} fields are:
18515 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
18516 The prosody package.
18519 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
18520 The contents of the @code{prosody.cfg.lua} to use.
18523 For example, if your @code{prosody.cfg.lua} is just the empty
18524 string, you could instantiate a prosody service like this:
18527 (service prosody-service-type
18528 (opaque-prosody-configuration
18529 (prosody.cfg.lua "")))
18532 @c end of Prosody auto-generated documentation
18534 @subsubheading BitlBee Service
18536 @cindex IRC (Internet Relay Chat)
18537 @cindex IRC gateway
18538 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
18539 interface to a variety of messaging protocols such as XMPP.
18541 @defvr {Scheme Variable} bitlbee-service-type
18542 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
18543 gateway daemon. Its value is a @code{bitlbee-configuration} (see
18546 To have BitlBee listen on port 6667 on localhost, add this line to your
18550 (service bitlbee-service-type)
18554 @deftp {Data Type} bitlbee-configuration
18555 This is the configuration for BitlBee, with the following fields:
18558 @item @code{interface} (default: @code{"127.0.0.1"})
18559 @itemx @code{port} (default: @code{6667})
18560 Listen on the network interface corresponding to the IP address
18561 specified in @var{interface}, on @var{port}.
18563 When @var{interface} is @code{127.0.0.1}, only local clients can
18564 connect; when it is @code{0.0.0.0}, connections can come from any
18565 networking interface.
18567 @item @code{bitlbee} (default: @code{bitlbee})
18568 The BitlBee package to use.
18570 @item @code{plugins} (default: @code{'()})
18571 List of plugin packages to use---e.g., @code{bitlbee-discord}.
18573 @item @code{extra-settings} (default: @code{""})
18574 Configuration snippet added as-is to the BitlBee configuration file.
18578 @subsubheading Quassel Service
18580 @cindex IRC (Internet Relay Chat)
18581 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
18582 meaning that one or more clients can attach to and detach from the
18585 @defvr {Scheme Variable} quassel-service-type
18586 This is the service type for the @url{https://quassel-irc.org/,Quassel}
18587 IRC backend daemon. Its value is a @code{quassel-configuration}
18591 @deftp {Data Type} quassel-configuration
18592 This is the configuration for Quassel, with the following fields:
18595 @item @code{quassel} (default: @code{quassel})
18596 The Quassel package to use.
18598 @item @code{interface} (default: @code{"::,0.0.0.0"})
18599 @item @code{port} (default: @code{4242})
18600 Listen on the network interface(s) corresponding to the IPv4 or IPv6
18601 interfaces specified in the comma delimited @var{interface}, on
18604 @item @code{loglevel} (default: @code{"Info"})
18605 The level of logging desired. Accepted values are Debug, Info, Warning
18610 @node Telephony Services
18611 @subsection Telephony Services
18613 @cindex Murmur (VoIP server)
18614 @cindex VoIP server
18615 This section describes how to set up and run a Murmur server. Murmur is
18616 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
18619 @deftp {Data Type} murmur-configuration
18620 The service type for the Murmur server. An example configuration can
18624 (service murmur-service-type
18625 (murmur-configuration
18627 "Welcome to this Mumble server running on Guix!")
18628 (cert-required? #t) ;disallow text password logins
18629 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
18630 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
18633 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
18634 password with the command that is printed during the activation phase.
18636 It is recommended to register a normal Mumble user account
18637 and grant it admin or moderator rights.
18638 You can use the @code{mumble} client to
18639 login as new normal user, register yourself, and log out.
18640 For the next step login with the name @code{SuperUser} use
18641 the @code{SuperUser} password that you set previously,
18642 and grant your newly registered mumble user administrator or moderator
18643 rights and create some channels.
18645 Available @code{murmur-configuration} fields are:
18648 @item @code{package} (default: @code{mumble})
18649 Package that contains @code{bin/murmurd}.
18651 @item @code{user} (default: @code{"murmur"})
18652 User who will run the Murmur server.
18654 @item @code{group} (default: @code{"murmur"})
18655 Group of the user who will run the murmur server.
18657 @item @code{port} (default: @code{64738})
18658 Port on which the server will listen.
18660 @item @code{welcome-text} (default: @code{""})
18661 Welcome text sent to clients when they connect.
18663 @item @code{server-password} (default: @code{""})
18664 Password the clients have to enter in order to connect.
18666 @item @code{max-users} (default: @code{100})
18667 Maximum of users that can be connected to the server at once.
18669 @item @code{max-user-bandwidth} (default: @code{#f})
18670 Maximum voice traffic a user can send per second.
18672 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
18673 File name of the sqlite database.
18674 The service's user will become the owner of the directory.
18676 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
18677 File name of the log file.
18678 The service's user will become the owner of the directory.
18680 @item @code{autoban-attempts} (default: @code{10})
18681 Maximum number of logins a user can make in @code{autoban-timeframe}
18682 without getting auto banned for @code{autoban-time}.
18684 @item @code{autoban-timeframe} (default: @code{120})
18685 Timeframe for autoban in seconds.
18687 @item @code{autoban-time} (default: @code{300})
18688 Amount of time in seconds for which a client gets banned
18689 when violating the autoban limits.
18691 @item @code{opus-threshold} (default: @code{100})
18692 Percentage of clients that need to support opus
18693 before switching over to opus audio codec.
18695 @item @code{channel-nesting-limit} (default: @code{10})
18696 How deep channels can be nested at maximum.
18698 @item @code{channelname-regex} (default: @code{#f})
18699 A string in form of a Qt regular expression that channel names must conform to.
18701 @item @code{username-regex} (default: @code{#f})
18702 A string in form of a Qt regular expression that user names must conform to.
18704 @item @code{text-message-length} (default: @code{5000})
18705 Maximum size in bytes that a user can send in one text chat message.
18707 @item @code{image-message-length} (default: @code{(* 128 1024)})
18708 Maximum size in bytes that a user can send in one image message.
18710 @item @code{cert-required?} (default: @code{#f})
18711 If it is set to @code{#t} clients that use weak password authentication
18712 will not be accepted. Users must have completed the certificate wizard to join.
18714 @item @code{remember-channel?} (default: @code{#f})
18715 Should murmur remember the last channel each user was in when they disconnected
18716 and put them into the remembered channel when they rejoin.
18718 @item @code{allow-html?} (default: @code{#f})
18719 Should html be allowed in text messages, user comments, and channel descriptions.
18721 @item @code{allow-ping?} (default: @code{#f})
18722 Setting to true exposes the current user count, the maximum user count, and
18723 the server's maximum bandwidth per client to unauthenticated users. In the
18724 Mumble client, this information is shown in the Connect dialog.
18726 Disabling this setting will prevent public listing of the server.
18728 @item @code{bonjour?} (default: @code{#f})
18729 Should the server advertise itself in the local network through the bonjour protocol.
18731 @item @code{send-version?} (default: @code{#f})
18732 Should the murmur server version be exposed in ping requests.
18734 @item @code{log-days} (default: @code{31})
18735 Murmur also stores logs in the database, which are accessible via RPC.
18736 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
18737 or -1 to disable logging to the database.
18739 @item @code{obfuscate-ips?} (default: @code{#t})
18740 Should logged ips be obfuscated to protect the privacy of users.
18742 @item @code{ssl-cert} (default: @code{#f})
18743 File name of the SSL/TLS certificate used for encrypted connections.
18746 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
18748 @item @code{ssl-key} (default: @code{#f})
18749 Filepath to the ssl private key used for encrypted connections.
18751 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
18754 @item @code{ssl-dh-params} (default: @code{#f})
18755 File name of a PEM-encoded file with Diffie-Hellman parameters
18756 for the SSL/TLS encryption. Alternatively you set it to
18757 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
18758 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
18760 @item @code{ssl-ciphers} (default: @code{#f})
18761 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
18764 This option is specified using
18765 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
18766 OpenSSL cipher list notation}.
18768 It is recommended that you try your cipher string using 'openssl ciphers <string>'
18769 before setting it here, to get a feel for which cipher suites you will get.
18770 After setting this option, it is recommend that you inspect your Murmur log
18771 to ensure that Murmur is using the cipher suites that you expected it to.
18773 Note: Changing this option may impact the backwards compatibility of your
18774 Murmur server, and can remove the ability for older Mumble clients to be able
18777 @item @code{public-registration} (default: @code{#f})
18778 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
18780 You can optionally register your server in the public server list that the
18781 @code{mumble} client shows on startup.
18782 You cannot register your server if you have set a @code{server-password},
18783 or set @code{allow-ping} to @code{#f}.
18785 It might take a few hours until it shows up in the public list.
18787 @item @code{file} (default: @code{#f})
18788 Optional alternative override for this configuration.
18792 @deftp {Data Type} murmur-public-registration-configuration
18793 Configuration for public registration of a murmur service.
18797 This is a display name for your server. Not to be confused with the hostname.
18799 @item @code{password}
18800 A password to identify your registration.
18801 Subsequent updates will need the same password. Don't lose your password.
18804 This should be a @code{http://} or @code{https://} link to your web
18807 @item @code{hostname} (default: @code{#f})
18808 By default your server will be listed by its IP address.
18809 If it is set your server will be linked by this host name instead.
18815 @node Monitoring Services
18816 @subsection Monitoring Services
18818 @subsubheading Tailon Service
18820 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
18821 viewing and searching log files.
18823 The following example will configure the service with default values.
18824 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
18827 (service tailon-service-type)
18830 The following example customises more of the Tailon configuration,
18831 adding @command{sed} to the list of allowed commands.
18834 (service tailon-service-type
18835 (tailon-configuration
18837 (tailon-configuration-file
18838 (allowed-commands '("tail" "grep" "awk" "sed"))))))
18842 @deftp {Data Type} tailon-configuration
18843 Data type representing the configuration of Tailon.
18844 This type has the following parameters:
18847 @item @code{config-file} (default: @code{(tailon-configuration-file)})
18848 The configuration file to use for Tailon. This can be set to a
18849 @dfn{tailon-configuration-file} record value, or any gexp
18850 (@pxref{G-Expressions}).
18852 For example, to instead use a local file, the @code{local-file} function
18856 (service tailon-service-type
18857 (tailon-configuration
18858 (config-file (local-file "./my-tailon.conf"))))
18861 @item @code{package} (default: @code{tailon})
18862 The tailon package to use.
18867 @deftp {Data Type} tailon-configuration-file
18868 Data type representing the configuration options for Tailon.
18869 This type has the following parameters:
18872 @item @code{files} (default: @code{(list "/var/log")})
18873 List of files to display. The list can include strings for a single file
18874 or directory, or a list, where the first item is the name of a
18875 subsection, and the remaining items are the files or directories in that
18878 @item @code{bind} (default: @code{"localhost:8080"})
18879 Address and port to which Tailon should bind on.
18881 @item @code{relative-root} (default: @code{#f})
18882 URL path to use for Tailon, set to @code{#f} to not use a path.
18884 @item @code{allow-transfers?} (default: @code{#t})
18885 Allow downloading the log files in the web interface.
18887 @item @code{follow-names?} (default: @code{#t})
18888 Allow tailing of not-yet existent files.
18890 @item @code{tail-lines} (default: @code{200})
18891 Number of lines to read initially from each file.
18893 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
18894 Commands to allow running. By default, @code{sed} is disabled.
18896 @item @code{debug?} (default: @code{#f})
18897 Set @code{debug?} to @code{#t} to show debug messages.
18899 @item @code{wrap-lines} (default: @code{#t})
18900 Initial line wrapping state in the web interface. Set to @code{#t} to
18901 initially wrap lines (the default), or to @code{#f} to initially not
18904 @item @code{http-auth} (default: @code{#f})
18905 HTTP authentication type to use. Set to @code{#f} to disable
18906 authentication (the default). Supported values are @code{"digest"} or
18909 @item @code{users} (default: @code{#f})
18910 If HTTP authentication is enabled (see @code{http-auth}), access will be
18911 restricted to the credentials provided here. To configure users, use a
18912 list of pairs, where the first element of the pair is the username, and
18913 the 2nd element of the pair is the password.
18916 (tailon-configuration-file
18917 (http-auth "basic")
18918 (users '(("user1" . "password1")
18919 ("user2" . "password2"))))
18926 @subsubheading Darkstat Service
18928 Darkstat is a packet sniffer that captures network traffic, calculates
18929 statistics about usage, and serves reports over HTTP.
18931 @defvar {Scheme Variable} darkstat-service-type
18932 This is the service type for the
18933 @uref{https://unix4lyfe.org/darkstat/, darkstat}
18934 service, its value must be a @code{darkstat-configuration} record as in
18938 (service darkstat-service-type
18939 (darkstat-configuration
18940 (interface "eno1")))
18944 @deftp {Data Type} darkstat-configuration
18945 Data type representing the configuration of @command{darkstat}.
18948 @item @code{package} (default: @code{darkstat})
18949 The darkstat package to use.
18951 @item @code{interface}
18952 Capture traffic on the specified network interface.
18954 @item @code{port} (default: @code{"667"})
18955 Bind the web interface to the specified port.
18957 @item @code{bind-address} (default: @code{"127.0.0.1"})
18958 Bind the web interface to the specified address.
18960 @item @code{base} (default: @code{"/"})
18961 Specify the path of the base URL. This can be useful if
18962 @command{darkstat} is accessed via a reverse proxy.
18967 @subsubheading Prometheus Node Exporter Service
18969 @cindex prometheus-node-exporter
18970 The Prometheus ``node exporter'' makes hardware and operating system statistics
18971 provided by the Linux kernel available for the Prometheus monitoring system.
18972 This service should be deployed on all physical nodes and virtual machines,
18973 where monitoring these statistics is desirable.
18975 @defvar {Scheme variable} prometheus-node-exporter-service-type
18976 This is the service type for the
18977 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
18978 service, its value must be a @code{prometheus-node-exporter-configuration}
18979 record as in this example:
18982 (service prometheus-node-exporter-service-type
18983 (prometheus-node-exporter-configuration
18984 (web-listen-address ":9100")))
18988 @deftp {Data Type} prometheus-node-exporter-configuration
18989 Data type representing the configuration of @command{node_exporter}.
18992 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
18993 The prometheus-node-exporter package to use.
18995 @item @code{web-listen-address} (default: @code{":9100"})
18996 Bind the web interface to the specified address.
19001 @subsubheading Zabbix server
19002 @cindex zabbix zabbix-server
19003 Zabbix provides monitoring metrics, among others network utilization, CPU load
19004 and disk space consumption:
19007 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
19008 @item Auto-discovery of servers and network devices and interfaces.
19009 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
19010 @item Distributed monitoring with centralized web administration.
19011 @item Native high performance agents.
19012 @item SLA, and ITIL KPI metrics on reporting.
19013 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
19014 @item Remote command execution through Zabbix proxies.
19017 @c %start of fragment
19019 Available @code{zabbix-server-configuration} fields are:
19021 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
19022 The zabbix-server package.
19026 @deftypevr {@code{zabbix-server-configuration} parameter} string user
19027 User who will run the Zabbix server.
19029 Defaults to @samp{"zabbix"}.
19033 @deftypevr {@code{zabbix-server-configuration} parameter} group group
19034 Group who will run the Zabbix server.
19036 Defaults to @samp{"zabbix"}.
19040 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
19041 Database host name.
19043 Defaults to @samp{"127.0.0.1"}.
19047 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
19050 Defaults to @samp{"zabbix"}.
19054 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
19057 Defaults to @samp{"zabbix"}.
19061 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
19062 Database password. Please, use @code{include-files} with
19063 @code{DBPassword=SECRET} inside a specified file instead.
19065 Defaults to @samp{""}.
19069 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
19072 Defaults to @samp{5432}.
19076 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
19077 Specifies where log messages are written to:
19081 @code{system} - syslog.
19084 @code{file} - file specified with @code{log-file} parameter.
19087 @code{console} - standard output.
19091 Defaults to @samp{""}.
19095 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
19096 Log file name for @code{log-type} @code{file} parameter.
19098 Defaults to @samp{"/var/log/zabbix/server.log"}.
19102 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
19105 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
19109 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
19110 The location of certificate authority (CA) files for SSL server
19111 certificate verification.
19113 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
19117 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
19118 Location of SSL client certificates.
19120 Defaults to @samp{"/etc/ssl/certs"}.
19124 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
19125 Extra options will be appended to Zabbix server configuration file.
19127 Defaults to @samp{""}.
19131 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
19132 You may include individual files or all files in a directory in the
19133 configuration file.
19135 Defaults to @samp{()}.
19139 @c %end of fragment
19141 @subsubheading Zabbix agent
19142 @cindex zabbix zabbix-agent
19144 Zabbix agent gathers information for Zabbix server.
19146 @c %start of fragment
19148 Available @code{zabbix-agent-configuration} fields are:
19150 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
19151 The zabbix-agent package.
19155 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
19156 User who will run the Zabbix agent.
19158 Defaults to @samp{"zabbix"}.
19162 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
19163 Group who will run the Zabbix agent.
19165 Defaults to @samp{"zabbix"}.
19169 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
19170 Unique, case sensitive hostname which is required for active checks and
19171 must match hostname as configured on the server.
19173 Defaults to @samp{"Zabbix server"}.
19177 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
19178 Specifies where log messages are written to:
19182 @code{system} - syslog.
19185 @code{file} - file specified with @code{log-file} parameter.
19188 @code{console} - standard output.
19192 Defaults to @samp{""}.
19196 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
19197 Log file name for @code{log-type} @code{file} parameter.
19199 Defaults to @samp{"/var/log/zabbix/agent.log"}.
19203 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
19206 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
19210 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
19211 List of IP addresses, optionally in CIDR notation, or hostnames of
19212 Zabbix servers and Zabbix proxies. Incoming connections will be
19213 accepted only from the hosts listed here.
19215 Defaults to @samp{("127.0.0.1")}.
19219 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
19220 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
19221 proxies for active checks. If port is not specified, default port is
19222 used. If this parameter is not specified, active checks are disabled.
19224 Defaults to @samp{("127.0.0.1")}.
19228 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
19229 Extra options will be appended to Zabbix server configuration file.
19231 Defaults to @samp{""}.
19235 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
19236 You may include individual files or all files in a directory in the
19237 configuration file.
19239 Defaults to @samp{()}.
19243 @c %end of fragment
19245 @subsubheading Zabbix front-end
19246 @cindex zabbix zabbix-front-end
19248 This service provides a WEB interface to Zabbix server.
19250 @c %start of fragment
19252 Available @code{zabbix-front-end-configuration} fields are:
19254 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
19255 NGINX configuration.
19259 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
19260 Database host name.
19262 Defaults to @samp{"localhost"}.
19266 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
19269 Defaults to @samp{5432}.
19273 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
19276 Defaults to @samp{"zabbix"}.
19280 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
19283 Defaults to @samp{"zabbix"}.
19287 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
19288 Database password. Please, use @code{db-secret-file} instead.
19290 Defaults to @samp{""}.
19294 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
19295 Secret file which will be appended to @file{zabbix.conf.php} file. This
19296 file contains credentials for use by Zabbix front-end. You are expected
19297 to create it manually.
19299 Defaults to @samp{""}.
19303 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
19304 Zabbix server hostname.
19306 Defaults to @samp{"localhost"}.
19310 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
19311 Zabbix server port.
19313 Defaults to @samp{10051}.
19318 @c %end of fragment
19320 @node Kerberos Services
19321 @subsection Kerberos Services
19324 The @code{(gnu services kerberos)} module provides services relating to
19325 the authentication protocol @dfn{Kerberos}.
19327 @subsubheading Krb5 Service
19329 Programs using a Kerberos client library normally
19330 expect a configuration file in @file{/etc/krb5.conf}.
19331 This service generates such a file from a definition provided in the
19332 operating system declaration.
19333 It does not cause any daemon to be started.
19335 No ``keytab'' files are provided by this service---you must explicitly create them.
19336 This service is known to work with the MIT client library, @code{mit-krb5}.
19337 Other implementations have not been tested.
19339 @defvr {Scheme Variable} krb5-service-type
19340 A service type for Kerberos 5 clients.
19344 Here is an example of its use:
19346 (service krb5-service-type
19347 (krb5-configuration
19348 (default-realm "EXAMPLE.COM")
19349 (allow-weak-crypto? #t)
19352 (name "EXAMPLE.COM")
19353 (admin-server "groucho.example.com")
19354 (kdc "karl.example.com"))
19357 (admin-server "kerb-admin.argrx.edu")
19358 (kdc "keys.argrx.edu"))))))
19362 This example provides a Kerberos@tie{}5 client configuration which:
19364 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
19365 of which have distinct administration servers and key distribution centers;
19366 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
19367 specified by clients;
19368 @item Accepts services which only support encryption types known to be weak.
19371 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
19372 Only the most commonly used ones are described here.
19373 For a full list, and more detailed explanation of each, see the MIT
19374 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
19378 @deftp {Data Type} krb5-realm
19379 @cindex realm, kerberos
19382 This field is a string identifying the name of the realm.
19383 A common convention is to use the fully qualified DNS name of your organization,
19384 converted to upper case.
19386 @item @code{admin-server}
19387 This field is a string identifying the host where the administration server is
19391 This field is a string identifying the key distribution center
19396 @deftp {Data Type} krb5-configuration
19399 @item @code{allow-weak-crypto?} (default: @code{#f})
19400 If this flag is @code{#t} then services which only offer encryption algorithms
19401 known to be weak will be accepted.
19403 @item @code{default-realm} (default: @code{#f})
19404 This field should be a string identifying the default Kerberos
19405 realm for the client.
19406 You should set this field to the name of your Kerberos realm.
19407 If this value is @code{#f}
19408 then a realm must be specified with every Kerberos principal when invoking programs
19409 such as @command{kinit}.
19411 @item @code{realms}
19412 This should be a non-empty list of @code{krb5-realm} objects, which clients may
19414 Normally, one of them will have a @code{name} field matching the @code{default-realm}
19420 @subsubheading PAM krb5 Service
19423 The @code{pam-krb5} service allows for login authentication and password
19424 management via Kerberos.
19425 You will need this service if you want PAM enabled applications to authenticate
19426 users using Kerberos.
19428 @defvr {Scheme Variable} pam-krb5-service-type
19429 A service type for the Kerberos 5 PAM module.
19432 @deftp {Data Type} pam-krb5-configuration
19433 Data type representing the configuration of the Kerberos 5 PAM module.
19434 This type has the following parameters:
19436 @item @code{pam-krb5} (default: @code{pam-krb5})
19437 The pam-krb5 package to use.
19439 @item @code{minimum-uid} (default: @code{1000})
19440 The smallest user ID for which Kerberos authentications should be attempted.
19441 Local accounts with lower values will silently fail to authenticate.
19446 @node LDAP Services
19447 @subsection LDAP Services
19449 @cindex nslcd, LDAP service
19451 The @code{(gnu services authentication)} module provides the
19452 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
19453 server. In addition to configuring the service itself, you may want to add
19454 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
19455 Switch} for detailed information.
19457 Here is a simple operating system declaration with a default configuration of
19458 the @code{nslcd-service-type} and a Name Service Switch configuration that
19459 consults the @code{ldap} name service last:
19462 (use-service-modules authentication)
19463 (use-modules (gnu system nss))
19469 (service nslcd-service-type)
19470 (service dhcp-client-service-type)
19472 (name-service-switch
19473 (let ((services (list (name-service (name "db"))
19474 (name-service (name "files"))
19475 (name-service (name "ldap")))))
19476 (name-service-switch
19477 (inherit %mdns-host-lookup-nss)
19478 (password services)
19481 (netgroup services)
19482 (gshadow services)))))
19485 @c %start of generated documentation for nslcd-configuration
19487 Available @code{nslcd-configuration} fields are:
19489 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
19490 The @code{nss-pam-ldapd} package to use.
19494 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
19495 The number of threads to start that can handle requests and perform LDAP
19496 queries. Each thread opens a separate connection to the LDAP server.
19497 The default is to start 5 threads.
19499 Defaults to @samp{disabled}.
19503 @deftypevr {@code{nslcd-configuration} parameter} string uid
19504 This specifies the user id with which the daemon should be run.
19506 Defaults to @samp{"nslcd"}.
19510 @deftypevr {@code{nslcd-configuration} parameter} string gid
19511 This specifies the group id with which the daemon should be run.
19513 Defaults to @samp{"nslcd"}.
19517 @deftypevr {@code{nslcd-configuration} parameter} log-option log
19518 This option controls the way logging is done via a list containing
19519 SCHEME and LEVEL. The SCHEME argument may either be the symbols "none"
19520 or "syslog", or an absolute file name. The LEVEL argument is optional
19521 and specifies the log level. The log level may be one of the following
19522 symbols: "crit", "error", "warning", "notice", "info" or "debug". All
19523 messages with the specified log level or higher are logged.
19525 Defaults to @samp{("/var/log/nslcd" info)}.
19529 @deftypevr {@code{nslcd-configuration} parameter} list uri
19530 The list of LDAP server URIs. Normally, only the first server will be
19531 used with the following servers as fall-back.
19533 Defaults to @samp{("ldap://localhost:389/")}.
19537 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
19538 The version of the LDAP protocol to use. The default is to use the
19539 maximum version supported by the LDAP library.
19541 Defaults to @samp{disabled}.
19545 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
19546 Specifies the distinguished name with which to bind to the directory
19547 server for lookups. The default is to bind anonymously.
19549 Defaults to @samp{disabled}.
19553 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
19554 Specifies the credentials with which to bind. This option is only
19555 applicable when used with binddn.
19557 Defaults to @samp{disabled}.
19561 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
19562 Specifies the distinguished name to use when the root user tries to
19563 modify a user's password using the PAM module.
19565 Defaults to @samp{disabled}.
19569 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
19570 Specifies the credentials with which to bind if the root user tries to
19571 change a user's password. This option is only applicable when used with
19574 Defaults to @samp{disabled}.
19578 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
19579 Specifies the SASL mechanism to be used when performing SASL
19582 Defaults to @samp{disabled}.
19586 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
19587 Specifies the SASL realm to be used when performing SASL authentication.
19589 Defaults to @samp{disabled}.
19593 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
19594 Specifies the authentication identity to be used when performing SASL
19597 Defaults to @samp{disabled}.
19601 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
19602 Specifies the authorization identity to be used when performing SASL
19605 Defaults to @samp{disabled}.
19609 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
19610 Determines whether the LDAP server host name should be canonicalised. If
19611 this is enabled the LDAP library will do a reverse host name lookup. By
19612 default, it is left up to the LDAP library whether this check is
19615 Defaults to @samp{disabled}.
19619 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
19620 Set the name for the GSS-API Kerberos credentials cache.
19622 Defaults to @samp{disabled}.
19626 @deftypevr {@code{nslcd-configuration} parameter} string base
19627 The directory search base.
19629 Defaults to @samp{"dc=example,dc=com"}.
19633 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
19634 Specifies the search scope (subtree, onelevel, base or children). The
19635 default scope is subtree; base scope is almost never useful for name
19636 service lookups; children scope is not supported on all servers.
19638 Defaults to @samp{(subtree)}.
19642 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
19643 Specifies the policy for dereferencing aliases. The default policy is
19644 to never dereference aliases.
19646 Defaults to @samp{disabled}.
19650 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
19651 Specifies whether automatic referral chasing should be enabled. The
19652 default behaviour is to chase referrals.
19654 Defaults to @samp{disabled}.
19658 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
19659 This option allows for custom attributes to be looked up instead of the
19660 default RFC 2307 attributes. It is a list of maps, each consisting of
19661 the name of a map, the RFC 2307 attribute to match and the query
19662 expression for the attribute as it is available in the directory.
19664 Defaults to @samp{()}.
19668 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
19669 A list of filters consisting of the name of a map to which the filter
19670 applies and an LDAP search filter expression.
19672 Defaults to @samp{()}.
19676 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
19677 Specifies the time limit in seconds to use when connecting to the
19678 directory server. The default value is 10 seconds.
19680 Defaults to @samp{disabled}.
19684 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
19685 Specifies the time limit (in seconds) to wait for a response from the
19686 LDAP server. A value of zero, which is the default, is to wait
19687 indefinitely for searches to be completed.
19689 Defaults to @samp{disabled}.
19693 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
19694 Specifies the period if inactivity (in seconds) after which the con‐
19695 nection to the LDAP server will be closed. The default is not to time
19698 Defaults to @samp{disabled}.
19702 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
19703 Specifies the number of seconds to sleep when connecting to all LDAP
19704 servers fails. By default one second is waited between the first
19705 failure and the first retry.
19707 Defaults to @samp{disabled}.
19711 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
19712 Specifies the time after which the LDAP server is considered to be
19713 permanently unavailable. Once this time is reached retries will be done
19714 only once per this time period. The default value is 10 seconds.
19716 Defaults to @samp{disabled}.
19720 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
19721 Specifies whether to use SSL/TLS or not (the default is not to). If
19722 'start-tls is specified then StartTLS is used rather than raw LDAP over
19725 Defaults to @samp{disabled}.
19729 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
19730 Specifies what checks to perform on a server-supplied certificate. The
19731 meaning of the values is described in the ldap.conf(5) manual page.
19733 Defaults to @samp{disabled}.
19737 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
19738 Specifies the directory containing X.509 certificates for peer authen‐
19739 tication. This parameter is ignored when using GnuTLS.
19741 Defaults to @samp{disabled}.
19745 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
19746 Specifies the path to the X.509 certificate for peer authentication.
19748 Defaults to @samp{disabled}.
19752 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
19753 Specifies the path to an entropy source. This parameter is ignored when
19756 Defaults to @samp{disabled}.
19760 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
19761 Specifies the ciphers to use for TLS as a string.
19763 Defaults to @samp{disabled}.
19767 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
19768 Specifies the path to the file containing the local certificate for
19769 client TLS authentication.
19771 Defaults to @samp{disabled}.
19775 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
19776 Specifies the path to the file containing the private key for client TLS
19779 Defaults to @samp{disabled}.
19783 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
19784 Set this to a number greater than 0 to request paged results from the
19785 LDAP server in accordance with RFC2696. The default (0) is to not
19786 request paged results.
19788 Defaults to @samp{disabled}.
19792 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
19793 This option prevents group membership lookups through LDAP for the
19794 specified users. Alternatively, the value 'all-local may be used. With
19795 that value nslcd builds a full list of non-LDAP users on startup.
19797 Defaults to @samp{disabled}.
19801 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
19802 This option ensures that LDAP users with a numeric user id lower than
19803 the specified value are ignored.
19805 Defaults to @samp{disabled}.
19809 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
19810 This option specifies an offset that is added to all LDAP numeric user
19811 ids. This can be used to avoid user id collisions with local users.
19813 Defaults to @samp{disabled}.
19817 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
19818 This option specifies an offset that is added to all LDAP numeric group
19819 ids. This can be used to avoid user id collisions with local groups.
19821 Defaults to @samp{disabled}.
19825 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
19826 If this option is set, the member attribute of a group may point to
19827 another group. Members of nested groups are also returned in the higher
19828 level group and parent groups are returned when finding groups for a
19829 specific user. The default is not to perform extra searches for nested
19832 Defaults to @samp{disabled}.
19836 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
19837 If this option is set, the group member list is not retrieved when
19838 looking up groups. Lookups for finding which groups a user belongs to
19839 will remain functional so the user will likely still get the correct
19840 groups assigned on login.
19842 Defaults to @samp{disabled}.
19846 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
19847 If this option is set, functions which cause all user/group entries to
19848 be loaded from the directory will not succeed in doing so. This can
19849 dramatically reduce LDAP server load in situations where there are a
19850 great number of users and/or groups. This option is not recommended for
19851 most configurations.
19853 Defaults to @samp{disabled}.
19857 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
19858 This option can be used to specify how user and group names are verified
19859 within the system. This pattern is used to check all user and group
19860 names that are requested and returned from LDAP.
19862 Defaults to @samp{disabled}.
19866 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
19867 This specifies whether or not to perform searches using case-insensitive
19868 matching. Enabling this could open up the system to authorization
19869 bypass vulnerabilities and introduce nscd cache poisoning
19870 vulnerabilities which allow denial of service.
19872 Defaults to @samp{disabled}.
19876 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
19877 This option specifies whether password policy controls are requested and
19878 handled from the LDAP server when performing user authentication.
19880 Defaults to @samp{disabled}.
19884 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
19885 By default nslcd performs an LDAP search with the user's credentials
19886 after BIND (authentication) to ensure that the BIND operation was
19887 successful. The default search is a simple check to see if the user's
19888 DN exists. A search filter can be specified that will be used instead.
19889 It should return at least one entry.
19891 Defaults to @samp{disabled}.
19895 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
19896 This option allows flexible fine tuning of the authorisation check that
19897 should be performed. The search filter specified is executed and if any
19898 entries match, access is granted, otherwise access is denied.
19900 Defaults to @samp{disabled}.
19904 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
19905 If this option is set password modification using pam_ldap will be
19906 denied and the specified message will be presented to the user instead.
19907 The message can be used to direct the user to an alternative means of
19908 changing their password.
19910 Defaults to @samp{disabled}.
19914 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
19915 List of pam service names for which LDAP authentication should suffice.
19917 Defaults to @samp{()}.
19921 @c %end of generated documentation for nslcd-configuration
19925 @subsection Web Services
19930 The @code{(gnu services web)} module provides the Apache HTTP Server,
19931 the nginx web server, and also a fastcgi wrapper daemon.
19933 @subsubheading Apache HTTP Server
19935 @deffn {Scheme Variable} httpd-service-type
19936 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
19937 (@dfn{httpd}). The value for this service type is a
19938 @code{httpd-configuration} record.
19940 A simple example configuration is given below.
19943 (service httpd-service-type
19944 (httpd-configuration
19947 (server-name "www.example.com")
19948 (document-root "/srv/http/www.example.com")))))
19951 Other services can also extend the @code{httpd-service-type} to add to
19955 (simple-service 'www.example.com-server httpd-service-type
19959 (list (string-join '("ServerName www.example.com"
19960 "DocumentRoot /srv/http/www.example.com")
19965 The details for the @code{httpd-configuration}, @code{httpd-module},
19966 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
19969 @deffn {Data Type} httpd-configuration
19970 This data type represents the configuration for the httpd service.
19973 @item @code{package} (default: @code{httpd})
19974 The httpd package to use.
19976 @item @code{pid-file} (default: @code{"/var/run/httpd"})
19977 The pid file used by the shepherd-service.
19979 @item @code{config} (default: @code{(httpd-config-file)})
19980 The configuration file to use with the httpd service. The default value
19981 is a @code{httpd-config-file} record, but this can also be a different
19982 G-expression that generates a file, for example a @code{plain-file}. A
19983 file outside of the store can also be specified through a string.
19988 @deffn {Data Type} httpd-module
19989 This data type represents a module for the httpd service.
19993 The name of the module.
19996 The file for the module. This can be relative to the httpd package being
19997 used, the absolute location of a file, or a G-expression for a file
19998 within the store, for example @code{(file-append mod-wsgi
19999 "/modules/mod_wsgi.so")}.
20004 @defvr {Scheme Variable} %default-httpd-modules
20005 A default list of @code{httpd-module} objects.
20008 @deffn {Data Type} httpd-config-file
20009 This data type represents a configuration file for the httpd service.
20012 @item @code{modules} (default: @code{%default-httpd-modules})
20013 The modules to load. Additional modules can be added here, or loaded by
20014 additional configuration.
20016 For example, in order to handle requests for PHP files, you can use Apache’s
20017 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
20020 (service httpd-service-type
20021 (httpd-configuration
20026 (name "proxy_module")
20027 (file "modules/mod_proxy.so"))
20029 (name "proxy_fcgi_module")
20030 (file "modules/mod_proxy_fcgi.so"))
20031 %default-httpd-modules))
20032 (extra-config (list "\
20033 <FilesMatch \\.php$>
20034 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
20035 </FilesMatch>"))))))
20036 (service php-fpm-service-type
20037 (php-fpm-configuration
20038 (socket "/var/run/php-fpm.sock")
20039 (socket-group "httpd")))
20042 @item @code{server-root} (default: @code{httpd})
20043 The @code{ServerRoot} in the configuration file, defaults to the httpd
20044 package. Directives including @code{Include} and @code{LoadModule} are
20045 taken as relative to the server root.
20047 @item @code{server-name} (default: @code{#f})
20048 The @code{ServerName} in the configuration file, used to specify the
20049 request scheme, hostname and port that the server uses to identify
20052 This doesn't need to be set in the server config, and can be specified
20053 in virtual hosts. The default is @code{#f} to not specify a
20056 @item @code{document-root} (default: @code{"/srv/http"})
20057 The @code{DocumentRoot} from which files will be served.
20059 @item @code{listen} (default: @code{'("80")})
20060 The list of values for the @code{Listen} directives in the config
20061 file. The value should be a list of strings, when each string can
20062 specify the port number to listen on, and optionally the IP address and
20065 @item @code{pid-file} (default: @code{"/var/run/httpd"})
20066 The @code{PidFile} to use. This should match the @code{pid-file} set in
20067 the @code{httpd-configuration} so that the Shepherd service is
20068 configured correctly.
20070 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
20071 The @code{ErrorLog} to which the server will log errors.
20073 @item @code{user} (default: @code{"httpd"})
20074 The @code{User} which the server will answer requests as.
20076 @item @code{group} (default: @code{"httpd"})
20077 The @code{Group} which the server will answer requests as.
20079 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
20080 A flat list of strings and G-expressions which will be added to the end
20081 of the configuration file.
20083 Any values which the service is extended with will be appended to this
20089 @deffn {Data Type} httpd-virtualhost
20090 This data type represents a virtualhost configuration block for the httpd service.
20092 These should be added to the extra-config for the httpd-service.
20095 (simple-service 'www.example.com-server httpd-service-type
20099 (list (string-join '("ServerName www.example.com"
20100 "DocumentRoot /srv/http/www.example.com")
20105 @item @code{addresses-and-ports}
20106 The addresses and ports for the @code{VirtualHost} directive.
20108 @item @code{contents}
20109 The contents of the @code{VirtualHost} directive, this should be a list
20110 of strings and G-expressions.
20115 @subsubheading NGINX
20117 @deffn {Scheme Variable} nginx-service-type
20118 Service type for the @uref{https://nginx.org/,NGinx} web server. The
20119 value for this service type is a @code{<nginx-configuration>} record.
20121 A simple example configuration is given below.
20124 (service nginx-service-type
20125 (nginx-configuration
20127 (list (nginx-server-configuration
20128 (server-name '("www.example.com"))
20129 (root "/srv/http/www.example.com"))))))
20132 In addition to adding server blocks to the service configuration
20133 directly, this service can be extended by other services to add server
20134 blocks, as in this example:
20137 (simple-service 'my-extra-server nginx-service-type
20138 (list (nginx-server-configuration
20139 (root "/srv/http/extra-website")
20140 (try-files (list "$uri" "$uri/index.html")))))
20144 At startup, @command{nginx} has not yet read its configuration file, so
20145 it uses a default file to log error messages. If it fails to load its
20146 configuration file, that is where error messages are logged. After the
20147 configuration file is loaded, the default error log file changes as per
20148 configuration. In our case, startup error messages can be found in
20149 @file{/var/run/nginx/logs/error.log}, and after configuration in
20150 @file{/var/log/nginx/error.log}. The second location can be changed
20151 with the @var{log-directory} configuration option.
20153 @deffn {Data Type} nginx-configuration
20154 This data type represents the configuration for NGinx. Some
20155 configuration can be done through this and the other provided record
20156 types, or alternatively, a config file can be provided.
20159 @item @code{nginx} (default: @code{nginx})
20160 The nginx package to use.
20162 @item @code{log-directory} (default: @code{"/var/log/nginx"})
20163 The directory to which NGinx will write log files.
20165 @item @code{run-directory} (default: @code{"/var/run/nginx"})
20166 The directory in which NGinx will create a pid file, and write temporary
20169 @item @code{server-blocks} (default: @code{'()})
20170 A list of @dfn{server blocks} to create in the generated configuration
20171 file, the elements should be of type
20172 @code{<nginx-server-configuration>}.
20174 The following example would setup NGinx to serve @code{www.example.com}
20175 from the @code{/srv/http/www.example.com} directory, without using
20178 (service nginx-service-type
20179 (nginx-configuration
20181 (list (nginx-server-configuration
20182 (server-name '("www.example.com"))
20183 (root "/srv/http/www.example.com"))))))
20186 @item @code{upstream-blocks} (default: @code{'()})
20187 A list of @dfn{upstream blocks} to create in the generated configuration
20188 file, the elements should be of type
20189 @code{<nginx-upstream-configuration>}.
20191 Configuring upstreams through the @code{upstream-blocks} can be useful
20192 when combined with @code{locations} in the
20193 @code{<nginx-server-configuration>} records. The following example
20194 creates a server configuration with one location configuration, that
20195 will proxy requests to a upstream configuration, which will handle
20196 requests with two servers.
20201 (nginx-configuration
20203 (list (nginx-server-configuration
20204 (server-name '("www.example.com"))
20205 (root "/srv/http/www.example.com")
20208 (nginx-location-configuration
20210 (body '("proxy_pass http://server-proxy;"))))))))
20212 (list (nginx-upstream-configuration
20213 (name "server-proxy")
20214 (servers (list "server1.example.com"
20215 "server2.example.com")))))))
20218 @item @code{file} (default: @code{#f})
20219 If a configuration @var{file} is provided, this will be used, rather than
20220 generating a configuration file from the provided @code{log-directory},
20221 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
20222 proper operation, these arguments should match what is in @var{file} to ensure
20223 that the directories are created when the service is activated.
20225 This can be useful if you have an existing configuration file, or it's
20226 not possible to do what is required through the other parts of the
20227 nginx-configuration record.
20229 @item @code{server-names-hash-bucket-size} (default: @code{#f})
20230 Bucket size for the server names hash tables, defaults to @code{#f} to
20231 use the size of the processors cache line.
20233 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
20234 Maximum bucket size for the server names hash tables.
20236 @item @code{modules} (default: @code{'()})
20237 List of nginx dynamic modules to load. This should be a list of file
20238 names of loadable modules, as in this example:
20243 (file-append nginx-accept-language-module "\
20244 /etc/nginx/modules/ngx_http_accept_language_module.so")))
20247 @item @code{extra-content} (default: @code{""})
20248 Extra content for the @code{http} block. Should be string or a string
20249 valued G-expression.
20254 @deftp {Data Type} nginx-server-configuration
20255 Data type representing the configuration of an nginx server block.
20256 This type has the following parameters:
20259 @item @code{listen} (default: @code{'("80" "443 ssl")})
20260 Each @code{listen} directive sets the address and port for IP, or the
20261 path for a UNIX-domain socket on which the server will accept requests.
20262 Both address and port, or only address or only port can be specified.
20263 An address may also be a hostname, for example:
20266 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
20269 @item @code{server-name} (default: @code{(list 'default)})
20270 A list of server names this server represents. @code{'default} represents the
20271 default server for connections matching no other server.
20273 @item @code{root} (default: @code{"/srv/http"})
20274 Root of the website nginx will serve.
20276 @item @code{locations} (default: @code{'()})
20277 A list of @dfn{nginx-location-configuration} or
20278 @dfn{nginx-named-location-configuration} records to use within this
20281 @item @code{index} (default: @code{(list "index.html")})
20282 Index files to look for when clients ask for a directory. If it cannot be found,
20283 Nginx will send the list of files in the directory.
20285 @item @code{try-files} (default: @code{'()})
20286 A list of files whose existence is checked in the specified order.
20287 @code{nginx} will use the first file it finds to process the request.
20289 @item @code{ssl-certificate} (default: @code{#f})
20290 Where to find the certificate for secure connections. Set it to @code{#f} if
20291 you don't have a certificate or you don't want to use HTTPS.
20293 @item @code{ssl-certificate-key} (default: @code{#f})
20294 Where to find the private key for secure connections. Set it to @code{#f} if
20295 you don't have a key or you don't want to use HTTPS.
20297 @item @code{server-tokens?} (default: @code{#f})
20298 Whether the server should add its configuration to response.
20300 @item @code{raw-content} (default: @code{'()})
20301 A list of raw lines added to the server block.
20306 @deftp {Data Type} nginx-upstream-configuration
20307 Data type representing the configuration of an nginx @code{upstream}
20308 block. This type has the following parameters:
20312 Name for this group of servers.
20314 @item @code{servers}
20315 Specify the addresses of the servers in the group. The address can be
20316 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
20317 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
20318 prefix @samp{unix:}. For addresses using an IP address or domain name,
20319 the default port is 80, and a different port can be specified
20325 @deftp {Data Type} nginx-location-configuration
20326 Data type representing the configuration of an nginx @code{location}
20327 block. This type has the following parameters:
20331 URI which this location block matches.
20333 @anchor{nginx-location-configuration body}
20335 Body of the location block, specified as a list of strings. This can contain
20337 configuration directives. For example, to pass requests to a upstream
20338 server group defined using an @code{nginx-upstream-configuration} block,
20339 the following directive would be specified in the body @samp{(list "proxy_pass
20340 http://upstream-name;")}.
20345 @deftp {Data Type} nginx-named-location-configuration
20346 Data type representing the configuration of an nginx named location
20347 block. Named location blocks are used for request redirection, and not
20348 used for regular request processing. This type has the following
20353 Name to identify this location block.
20356 @xref{nginx-location-configuration body}, as the body for named location
20357 blocks can be used in a similar way to the
20358 @code{nginx-location-configuration body}. One restriction is that the
20359 body of a named location block cannot contain location blocks.
20364 @subsubheading Varnish Cache
20366 Varnish is a fast cache server that sits in between web applications
20367 and end users. It proxies requests from clients and caches the
20368 accessed URLs such that multiple requests for the same resource only
20369 creates one request to the back-end.
20371 @defvr {Scheme Variable} varnish-service-type
20372 Service type for the Varnish daemon.
20375 @deftp {Data Type} varnish-configuration
20376 Data type representing the @code{varnish} service configuration.
20377 This type has the following parameters:
20380 @item @code{package} (default: @code{varnish})
20381 The Varnish package to use.
20383 @item @code{name} (default: @code{"default"})
20384 A name for this Varnish instance. Varnish will create a directory in
20385 @file{/var/varnish/} with this name and keep temporary files there. If
20386 the name starts with a forward slash, it is interpreted as an absolute
20389 Pass the @code{-n} argument to other Varnish programs to connect to the
20390 named instance, e.g.@: @command{varnishncsa -n default}.
20392 @item @code{backend} (default: @code{"localhost:8080"})
20393 The backend to use. This option has no effect if @code{vcl} is set.
20395 @item @code{vcl} (default: #f)
20396 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
20397 is @code{#f}, Varnish will proxy @code{backend} using the default
20398 configuration. Otherwise this must be a file-like object with valid
20401 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
20402 For example, to mirror @url{http://www.gnu.org,www.gnu.org} with VCL you
20403 can do something along these lines:
20406 (define %gnu-mirror
20407 (plain-file "gnu.vcl"
20409 backend gnu @{ .host = \"www.gnu.org\"; @}"))
20413 (services (cons (service varnish-service-type
20414 (varnish-configuration
20416 (vcl %gnu-mirror)))
20420 The configuration of an already running Varnish instance can be inspected
20421 and changed using the @command{varnishadm} program.
20423 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
20424 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
20425 comprehensive documentation on Varnish and its configuration language.
20427 @item @code{listen} (default: @code{'("localhost:80")})
20428 List of addresses Varnish will listen on.
20430 @item @code{storage} (default: @code{'("malloc,128m")})
20431 List of storage backends that will be available in VCL.
20433 @item @code{parameters} (default: @code{'()})
20434 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
20436 @item @code{extra-options} (default: @code{'()})
20437 Additional arguments to pass to the @command{varnishd} process.
20442 @subsubheading Patchwork
20444 Patchwork is a patch tracking system. It can collect patches sent to a
20445 mailing list, and display them in a web interface.
20447 @defvr {Scheme Variable} patchwork-service-type
20448 Service type for Patchwork.
20451 The following example is an example of a minimal service for Patchwork, for
20452 the @code{patchwork.example.com} domain.
20455 (service patchwork-service-type
20456 (patchwork-configuration
20457 (domain "patchwork.example.com")
20459 (patchwork-settings-module
20460 (allowed-hosts (list domain))
20461 (default-from-email "patchwork@@patchwork.example.com")))
20462 (getmail-retriever-config
20463 (getmail-retriever-configuration
20464 (type "SimpleIMAPSSLRetriever")
20465 (server "imap.example.com")
20467 (username "patchwork")
20469 (list (file-append coreutils "/bin/cat")
20470 "/etc/getmail-patchwork-imap-password"))
20472 '((mailboxes . ("Patches"))))))))
20476 There are three records for configuring the Patchwork service. The
20477 @code{<patchwork-configuration>} relates to the configuration for Patchwork
20478 within the HTTPD service.
20480 The @code{settings-module} field within the @code{<patchwork-configuration>}
20481 record can be populated with the @code{<patchwork-settings-module>} record,
20482 which describes a settings module that is generated within the Guix store.
20484 For the @code{database-configuration} field within the
20485 @code{<patchwork-settings-module>}, the
20486 @code{<patchwork-database-configuration>} must be used.
20488 @deftp {Data Type} patchwork-configuration
20489 Data type representing the Patchwork service configuration. This type has the
20490 following parameters:
20493 @item @code{patchwork} (default: @code{patchwork})
20494 The Patchwork package to use.
20496 @item @code{domain}
20497 The domain to use for Patchwork, this is used in the HTTPD service virtual
20500 @item @code{settings-module}
20501 The settings module to use for Patchwork. As a Django application, Patchwork
20502 is configured with a Python module containing the settings. This can either be
20503 an instance of the @code{<patchwork-settings-module>} record, any other record
20504 that represents the settings in the store, or a directory outside of the
20507 @item @code{static-path} (default: @code{"/static/"})
20508 The path under which the HTTPD service should serve the static files.
20510 @item @code{getmail-retriever-config}
20511 The getmail-retriever-configuration record value to use with
20512 Patchwork. Getmail will be configured with this value, the messages will be
20513 delivered to Patchwork.
20518 @deftp {Data Type} patchwork-settings-module
20519 Data type representing a settings module for Patchwork. Some of these
20520 settings relate directly to Patchwork, but others relate to Django, the web
20521 framework used by Patchwork, or the Django Rest Framework library. This type
20522 has the following parameters:
20525 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
20526 The database connection settings used for Patchwork. See the
20527 @code{<patchwork-database-configuration>} record type for more information.
20529 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
20530 Patchwork, as a Django web application uses a secret key for cryptographically
20531 signing values. This file should contain a unique unpredictable value.
20533 If this file does not exist, it will be created and populated with a random
20534 value by the patchwork-setup shepherd service.
20536 This setting relates to Django.
20538 @item @code{allowed-hosts}
20539 A list of valid hosts for this Patchwork service. This should at least include
20540 the domain specified in the @code{<patchwork-configuration>} record.
20542 This is a Django setting.
20544 @item @code{default-from-email}
20545 The email address from which Patchwork should send email by default.
20547 This is a Patchwork setting.
20549 @item @code{static-url} (default: @code{#f})
20550 The URL to use when serving static assets. It can be part of a URL, or a full
20551 URL, but must end in a @code{/}.
20553 If the default value is used, the @code{static-path} value from the
20554 @code{<patchwork-configuration>} record will be used.
20556 This is a Django setting.
20558 @item @code{admins} (default: @code{'()})
20559 Email addresses to send the details of errors that occur. Each value should
20560 be a list containing two elements, the name and then the email address.
20562 This is a Django setting.
20564 @item @code{debug?} (default: @code{#f})
20565 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
20566 messages will be shown.
20568 This is a Django setting.
20570 @item @code{enable-rest-api?} (default: @code{#t})
20571 Whether to enable the Patchwork REST API.
20573 This is a Patchwork setting.
20575 @item @code{enable-xmlrpc?} (default: @code{#t})
20576 Whether to enable the XML RPC API.
20578 This is a Patchwork setting.
20580 @item @code{force-https-links?} (default: @code{#t})
20581 Whether to use HTTPS links on Patchwork pages.
20583 This is a Patchwork setting.
20585 @item @code{extra-settings} (default: @code{""})
20586 Extra code to place at the end of the Patchwork settings module.
20591 @deftp {Data Type} patchwork-database-configuration
20592 Data type representing the database configuration for Patchwork.
20595 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
20596 The database engine to use.
20598 @item @code{name} (default: @code{"patchwork"})
20599 The name of the database to use.
20601 @item @code{user} (default: @code{"httpd"})
20602 The user to connect to the database as.
20604 @item @code{password} (default: @code{""})
20605 The password to use when connecting to the database.
20607 @item @code{host} (default: @code{""})
20608 The host to make the database connection to.
20610 @item @code{port} (default: @code{""})
20611 The port on which to connect to the database.
20616 @subsubheading Mumi
20618 @cindex Mumi, Debbugs Web interface
20619 @cindex Debbugs, Mumi Web interface
20620 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
20621 Web interface to the Debbugs bug tracker, by default for
20622 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
20623 but it also fetches and indexes mail retrieved from Debbugs.
20625 @defvr {Scheme Variable} mumi-service-type
20626 This is the service type for Mumi.
20629 @subsubheading FastCGI
20632 FastCGI is an interface between the front-end and the back-end of a web
20633 service. It is a somewhat legacy facility; new web services should
20634 generally just talk HTTP between the front-end and the back-end.
20635 However there are a number of back-end services such as PHP or the
20636 optimized HTTP Git repository access that use FastCGI, so we have
20637 support for it in Guix.
20639 To use FastCGI, you configure the front-end web server (e.g., nginx) to
20640 dispatch some subset of its requests to the fastcgi backend, which
20641 listens on a local TCP or UNIX socket. There is an intermediary
20642 @code{fcgiwrap} program that sits between the actual backend process and
20643 the web server. The front-end indicates which backend program to run,
20644 passing that information to the @code{fcgiwrap} process.
20646 @defvr {Scheme Variable} fcgiwrap-service-type
20647 A service type for the @code{fcgiwrap} FastCGI proxy.
20650 @deftp {Data Type} fcgiwrap-configuration
20651 Data type representing the configuration of the @code{fcgiwrap} service.
20652 This type has the following parameters:
20654 @item @code{package} (default: @code{fcgiwrap})
20655 The fcgiwrap package to use.
20657 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
20658 The socket on which the @code{fcgiwrap} process should listen, as a
20659 string. Valid @var{socket} values include
20660 @code{unix:@var{/path/to/unix/socket}},
20661 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
20662 @code{tcp6:[@var{ipv6_addr}]:port}.
20664 @item @code{user} (default: @code{fcgiwrap})
20665 @itemx @code{group} (default: @code{fcgiwrap})
20666 The user and group names, as strings, under which to run the
20667 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
20668 the user asks for the specific user or group names @code{fcgiwrap} that
20669 the corresponding user and/or group is present on the system.
20671 It is possible to configure a FastCGI-backed web service to pass HTTP
20672 authentication information from the front-end to the back-end, and to
20673 allow @code{fcgiwrap} to run the back-end process as a corresponding
20674 local user. To enable this capability on the back-end, run
20675 @code{fcgiwrap} as the @code{root} user and group. Note that this
20676 capability also has to be configured on the front-end as well.
20681 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
20682 with some additional features useful for sites of any size.
20684 These features include:
20686 @item Adaptive process spawning
20687 @item Basic statistics (similar to Apache's mod_status)
20688 @item Advanced process management with graceful stop/start
20689 @item Ability to start workers with different uid/gid/chroot/environment
20690 and different php.ini (replaces safe_mode)
20691 @item Stdout & stderr logging
20692 @item Emergency restart in case of accidental opcode cache destruction
20693 @item Accelerated upload support
20694 @item Support for a "slowlog"
20695 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
20696 a special function to finish request & flush all data while continuing to do
20697 something time-consuming (video converting, stats processing, etc.)
20699 ...@: and much more.
20701 @defvr {Scheme Variable} php-fpm-service-type
20702 A Service type for @code{php-fpm}.
20705 @deftp {Data Type} php-fpm-configuration
20706 Data Type for php-fpm service configuration.
20708 @item @code{php} (default: @code{php})
20709 The php package to use.
20710 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
20711 The address on which to accept FastCGI requests. Valid syntaxes are:
20713 @item @code{"ip.add.re.ss:port"}
20714 Listen on a TCP socket to a specific address on a specific port.
20715 @item @code{"port"}
20716 Listen on a TCP socket to all addresses on a specific port.
20717 @item @code{"/path/to/unix/socket"}
20718 Listen on a unix socket.
20721 @item @code{user} (default: @code{php-fpm})
20722 User who will own the php worker processes.
20723 @item @code{group} (default: @code{php-fpm})
20724 Group of the worker processes.
20725 @item @code{socket-user} (default: @code{php-fpm})
20726 User who can speak to the php-fpm socket.
20727 @item @code{socket-group} (default: @code{nginx})
20728 Group that can speak to the php-fpm socket.
20729 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
20730 The process id of the php-fpm process is written to this file
20731 once the service has started.
20732 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
20733 Log for the php-fpm master process.
20734 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
20735 Detailed settings for the php-fpm process manager.
20738 @item @code{<php-fpm-dynamic-process-manager-configuration>}
20739 @item @code{<php-fpm-static-process-manager-configuration>}
20740 @item @code{<php-fpm-on-demand-process-manager-configuration>}
20742 @item @code{display-errors} (default @code{#f})
20743 Determines whether php errors and warning should be sent to clients
20744 and displayed in their browsers.
20745 This is useful for local php development, but a security risk for public sites,
20746 as error messages can reveal passwords and personal data.
20747 @item @code{timezone} (default @code{#f})
20748 Specifies @code{php_admin_value[date.timezone]} parameter.
20749 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
20750 This file will log the @code{stderr} outputs of php worker processes.
20751 Can be set to @code{#f} to disable logging.
20752 @item @code{file} (default @code{#f})
20753 An optional override of the whole configuration.
20754 You can use the @code{mixed-text-file} function or an absolute filepath for it.
20758 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
20759 Data Type for the @code{dynamic} php-fpm process manager. With the
20760 @code{dynamic} process manager, spare worker processes are kept around
20761 based on it's configured limits.
20763 @item @code{max-children} (default: @code{5})
20764 Maximum of worker processes.
20765 @item @code{start-servers} (default: @code{2})
20766 How many worker processes should be started on start-up.
20767 @item @code{min-spare-servers} (default: @code{1})
20768 How many spare worker processes should be kept around at minimum.
20769 @item @code{max-spare-servers} (default: @code{3})
20770 How many spare worker processes should be kept around at maximum.
20774 @deftp {Data type} php-fpm-static-process-manager-configuration
20775 Data Type for the @code{static} php-fpm process manager. With the
20776 @code{static} process manager, an unchanging number of worker processes
20779 @item @code{max-children} (default: @code{5})
20780 Maximum of worker processes.
20784 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
20785 Data Type for the @code{on-demand} php-fpm process manager. With the
20786 @code{on-demand} process manager, worker processes are only created as
20789 @item @code{max-children} (default: @code{5})
20790 Maximum of worker processes.
20791 @item @code{process-idle-timeout} (default: @code{10})
20792 The time in seconds after which a process with no requests is killed.
20797 @deffn {Scheme Procedure} nginx-php-fpm-location @
20798 [#:nginx-package nginx] @
20799 [socket (string-append "/var/run/php" @
20800 (version-major (package-version php)) @
20802 A helper function to quickly add php to an @code{nginx-server-configuration}.
20805 A simple services setup for nginx with php can look like this:
20807 (services (cons* (service dhcp-client-service-type)
20808 (service php-fpm-service-type)
20809 (service nginx-service-type
20810 (nginx-server-configuration
20811 (server-name '("example.com"))
20812 (root "/srv/http/")
20814 (list (nginx-php-location)))
20816 (ssl-certificate #f)
20817 (ssl-certificate-key #f)))
20821 @cindex cat-avatar-generator
20822 The cat avatar generator is a simple service to demonstrate the use of php-fpm
20823 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
20824 the hash of a user's email address.
20826 @deffn {Scheme Procedure} cat-avatar-generator-service @
20827 [#:cache-dir "/var/cache/cat-avatar-generator"] @
20828 [#:package cat-avatar-generator] @
20829 [#:configuration (nginx-server-configuration)]
20830 Returns an nginx-server-configuration that inherits @code{configuration}. It
20831 extends the nginx configuration to add a server block that serves @code{package},
20832 a version of cat-avatar-generator. During execution, cat-avatar-generator will
20833 be able to use @code{cache-dir} as its cache directory.
20836 A simple setup for cat-avatar-generator can look like this:
20838 (services (cons* (cat-avatar-generator-service
20840 (nginx-server-configuration
20841 (server-name '("example.com"))))
20846 @subsubheading Hpcguix-web
20848 @cindex hpcguix-web
20849 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
20850 program is a customizable web interface to browse Guix packages,
20851 initially designed for users of high-performance computing (HPC)
20854 @defvr {Scheme Variable} hpcguix-web-service-type
20855 The service type for @code{hpcguix-web}.
20858 @deftp {Data Type} hpcguix-web-configuration
20859 Data type for the hpcguix-web service configuration.
20863 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
20864 configuration. The main items available in this spec are:
20867 @item @code{title-prefix} (default: @code{"hpcguix | "})
20868 The page title prefix.
20870 @item @code{guix-command} (default: @code{"guix"})
20871 The @command{guix} command.
20873 @item @code{package-filter-proc} (default: @code{(const #t)})
20874 A procedure specifying how to filter packages that are displayed.
20876 @item @code{package-page-extension-proc} (default: @code{(const '())})
20877 Extension package for @code{hpcguix-web}.
20879 @item @code{menu} (default: @code{'()})
20880 Additional entry in page @code{menu}.
20882 @item @code{channels} (default: @code{%default-channels})
20883 List of channels from which the package list is built (@pxref{Channels}).
20885 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
20886 The expiration time, in seconds, after which the package list is rebuilt from
20887 the latest instances of the given channels.
20890 See the hpcguix-web repository for a
20891 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
20894 @item @code{package} (default: @code{hpcguix-web})
20895 The hpcguix-web package to use.
20899 A typical hpcguix-web service declaration looks like this:
20902 (service hpcguix-web-service-type
20903 (hpcguix-web-configuration
20905 #~(define site-config
20906 (hpcweb-configuration
20907 (title-prefix "Guix-HPC - ")
20908 (menu '(("/about" "ABOUT"))))))))
20912 The hpcguix-web service periodically updates the package list it publishes by
20913 pulling channels from Git. To that end, it needs to access X.509 certificates
20914 so that it can authenticate Git servers when communicating over HTTPS, and it
20915 assumes that @file{/etc/ssl/certs} contains those certificates.
20917 Thus, make sure to add @code{nss-certs} or another certificate package to the
20918 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
20919 more information on X.509 certificates.
20922 @node Certificate Services
20923 @subsection Certificate Services
20926 @cindex HTTP, HTTPS
20927 @cindex Let's Encrypt
20928 @cindex TLS certificates
20929 The @code{(gnu services certbot)} module provides a service to
20930 automatically obtain a valid TLS certificate from the Let's Encrypt
20931 certificate authority. These certificates can then be used to serve
20932 content securely over HTTPS or other TLS-based protocols, with the
20933 knowledge that the client will be able to verify the server's
20936 @url{https://letsencrypt.org/, Let's Encrypt} provides the
20937 @code{certbot} tool to automate the certification process. This tool
20938 first securely generates a key on the server. It then makes a request
20939 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
20940 checks that the request originates from the host in question by using a
20941 challenge-response protocol, requiring the server to provide its
20942 response over HTTP. If that protocol completes successfully, the CA
20943 signs the key, resulting in a certificate. That certificate is valid
20944 for a limited period of time, and therefore to continue to provide TLS
20945 services, the server needs to periodically ask the CA to renew its
20948 The certbot service automates this process: the initial key
20949 generation, the initial certification request to the Let's Encrypt
20950 service, the web server challenge/response integration, writing the
20951 certificate to disk, the automated periodic renewals, and the deployment
20952 tasks associated with the renewal (e.g.@: reloading services, copying keys
20953 with different permissions).
20955 Certbot is run twice a day, at a random minute within the hour. It
20956 won't do anything until your certificates are due for renewal or
20957 revoked, but running it regularly would give your service a chance of
20958 staying online in case a Let's Encrypt-initiated revocation happened for
20961 By using this service, you agree to the ACME Subscriber Agreement, which
20962 can be found there:
20963 @url{https://acme-v01.api.letsencrypt.org/directory}.
20965 @defvr {Scheme Variable} certbot-service-type
20966 A service type for the @code{certbot} Let's Encrypt client. Its value
20967 must be a @code{certbot-configuration} record as in this example:
20970 (define %nginx-deploy-hook
20972 "nginx-deploy-hook"
20973 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
20974 (kill pid SIGHUP))))
20976 (service certbot-service-type
20977 (certbot-configuration
20978 (email "foo@@example.net")
20981 (certificate-configuration
20982 (domains '("example.net" "www.example.net"))
20983 (deploy-hook %nginx-deploy-hook))
20984 (certificate-configuration
20985 (domains '("bar.example.net")))))))
20988 See below for details about @code{certbot-configuration}.
20991 @deftp {Data Type} certbot-configuration
20992 Data type representing the configuration of the @code{certbot} service.
20993 This type has the following parameters:
20996 @item @code{package} (default: @code{certbot})
20997 The certbot package to use.
20999 @item @code{webroot} (default: @code{/var/www})
21000 The directory from which to serve the Let's Encrypt challenge/response
21003 @item @code{certificates} (default: @code{()})
21004 A list of @code{certificates-configuration}s for which to generate
21005 certificates and request signatures. Each certificate has a @code{name}
21006 and several @code{domains}.
21009 Mandatory email used for registration, recovery contact, and important
21010 account notifications.
21012 @item @code{server} (default: @code{#f})
21013 Optional URL of ACME server. Setting this overrides certbot's default,
21014 which is the Let's Encrypt server.
21016 @item @code{rsa-key-size} (default: @code{2048})
21017 Size of the RSA key.
21019 @item @code{default-location} (default: @i{see below})
21020 The default @code{nginx-location-configuration}. Because @code{certbot}
21021 needs to be able to serve challenges and responses, it needs to be able
21022 to run a web server. It does so by extending the @code{nginx} web
21023 service with an @code{nginx-server-configuration} listening on the
21024 @var{domains} on port 80, and which has a
21025 @code{nginx-location-configuration} for the @code{/.well-known/} URI
21026 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
21027 these nginx configuration data types.
21029 Requests to other URL paths will be matched by the
21030 @code{default-location}, which if present is added to all
21031 @code{nginx-server-configuration}s.
21033 By default, the @code{default-location} will issue a redirect from
21034 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
21035 you to define what to serve on your site via @code{https}.
21037 Pass @code{#f} to not issue a default location.
21041 @deftp {Data Type} certificate-configuration
21042 Data type representing the configuration of a certificate.
21043 This type has the following parameters:
21046 @item @code{name} (default: @i{see below})
21047 This name is used by Certbot for housekeeping and in file paths; it
21048 doesn't affect the content of the certificate itself. To see
21049 certificate names, run @code{certbot certificates}.
21051 Its default is the first provided domain.
21053 @item @code{domains} (default: @code{()})
21054 The first domain provided will be the subject CN of the certificate, and
21055 all domains will be Subject Alternative Names on the certificate.
21057 @item @code{challenge} (default: @code{#f})
21058 The challenge type that has to be run by certbot. If @code{#f} is specified,
21059 default to the HTTP challenge. If a value is specified, defaults to the
21060 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
21061 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
21062 and gives Let's Encrypt permission to log the public IP address of the
21063 requesting machine.
21065 @item @code{authentication-hook} (default: @code{#f})
21066 Command to be run in a shell once for each certificate challenge to be
21067 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
21068 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
21069 contains the validation string and @code{$CERTBOT_TOKEN} contains the
21070 file name of the resource requested when performing an HTTP-01 challenge.
21072 @item @code{cleanup-hook} (default: @code{#f})
21073 Command to be run in a shell once for each certificate challenge that
21074 have been answered by the @code{auth-hook}. For this command, the shell
21075 variables available in the @code{auth-hook} script are still available, and
21076 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
21077 of the @code{auth-hook} script.
21079 @item @code{deploy-hook} (default: @code{#f})
21080 Command to be run in a shell once for each successfully issued
21081 certificate. For this command, the shell variable
21082 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
21083 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
21084 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
21085 contain a space-delimited list of renewed certificate domains (for
21086 example, @samp{"example.com www.example.com"}.
21091 For each @code{certificate-configuration}, the certificate is saved to
21092 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
21093 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
21095 @subsection DNS Services
21096 @cindex DNS (domain name system)
21097 @cindex domain name system (DNS)
21099 The @code{(gnu services dns)} module provides services related to the
21100 @dfn{domain name system} (DNS). It provides a server service for hosting
21101 an @emph{authoritative} DNS server for multiple zones, slave or master.
21102 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
21103 caching and forwarding DNS server for the LAN, which uses
21104 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
21106 @subsubheading Knot Service
21108 An example configuration of an authoritative server for two zones, one master
21112 (define-zone-entries example.org.zone
21113 ;; Name TTL Class Type Data
21114 ("@@" "" "IN" "A" "127.0.0.1")
21115 ("@@" "" "IN" "NS" "ns")
21116 ("ns" "" "IN" "A" "127.0.0.1"))
21118 (define master-zone
21119 (knot-zone-configuration
21120 (domain "example.org")
21122 (origin "example.org")
21123 (entries example.org.zone)))))
21126 (knot-zone-configuration
21127 (domain "plop.org")
21128 (dnssec-policy "default")
21129 (master (list "plop-master"))))
21131 (define plop-master
21132 (knot-remote-configuration
21134 (address (list "208.76.58.171"))))
21138 (services (cons* (service knot-service-type
21139 (knot-configuration
21140 (remotes (list plop-master))
21141 (zones (list master-zone slave-zone))))
21146 @deffn {Scheme Variable} knot-service-type
21147 This is the type for the Knot DNS server.
21149 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
21150 zones, that is to say domain names you would buy from a registrar. This server
21151 is not a resolver, meaning that it can only resolve names for which it is
21152 authoritative. This server can be configured to serve zones as a master server
21153 or a slave server as a per-zone basis. Slave zones will get their data from
21154 masters, and will serve it as an authoritative server. From the point of view
21155 of a resolver, there is no difference between master and slave.
21157 The following data types are used to configure the Knot DNS server:
21160 @deftp {Data Type} knot-key-configuration
21161 Data type representing a key.
21162 This type has the following parameters:
21165 @item @code{id} (default: @code{""})
21166 An identifier for other configuration fields to refer to this key. IDs must
21167 be unique and must not be empty.
21169 @item @code{algorithm} (default: @code{#f})
21170 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
21171 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
21172 and @code{'hmac-sha512}.
21174 @item @code{secret} (default: @code{""})
21175 The secret key itself.
21180 @deftp {Data Type} knot-acl-configuration
21181 Data type representing an Access Control List (ACL) configuration.
21182 This type has the following parameters:
21185 @item @code{id} (default: @code{""})
21186 An identifier for ether configuration fields to refer to this key. IDs must be
21187 unique and must not be empty.
21189 @item @code{address} (default: @code{'()})
21190 An ordered list of IP addresses, network subnets, or network ranges represented
21191 with strings. The query must match one of them. Empty value means that
21192 address match is not required.
21194 @item @code{key} (default: @code{'()})
21195 An ordered list of references to keys represented with strings. The string
21196 must match a key ID defined in a @code{knot-key-configuration}. No key means
21197 that a key is not require to match that ACL.
21199 @item @code{action} (default: @code{'()})
21200 An ordered list of actions that are permitted or forbidden by this ACL. Possible
21201 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
21202 and @code{'update}.
21204 @item @code{deny?} (default: @code{#f})
21205 When true, the ACL defines restrictions. Listed actions are forbidden. When
21206 false, listed actions are allowed.
21211 @deftp {Data Type} zone-entry
21212 Data type representing a record entry in a zone file.
21213 This type has the following parameters:
21216 @item @code{name} (default: @code{"@@"})
21217 The name of the record. @code{"@@"} refers to the origin of the zone. Names
21218 are relative to the origin of the zone. For example, in the @code{example.org}
21219 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
21220 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
21221 refers to @code{ns.example.org}.
21223 @item @code{ttl} (default: @code{""})
21224 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
21226 @item @code{class} (default: @code{"IN"})
21227 The class of the record. Knot currently supports only @code{"IN"} and
21228 partially @code{"CH"}.
21230 @item @code{type} (default: @code{"A"})
21231 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
21232 address), NS (Name Server) and MX (Mail eXchange). Many other types are
21235 @item @code{data} (default: @code{""})
21236 The data contained in the record. For instance an IP address associated with
21237 an A record, or a domain name associated with an NS record. Remember that
21238 domain names are relative to the origin unless they end with a dot.
21243 @deftp {Data Type} zone-file
21244 Data type representing the content of a zone file.
21245 This type has the following parameters:
21248 @item @code{entries} (default: @code{'()})
21249 The list of entries. The SOA record is taken care of, so you don't need to
21250 put it in the list of entries. This list should probably contain an entry
21251 for your primary authoritative DNS server. Other than using a list of entries
21252 directly, you can use @code{define-zone-entries} to define a object containing
21253 the list of entries more easily, that you can later pass to the @code{entries}
21254 field of the @code{zone-file}.
21256 @item @code{origin} (default: @code{""})
21257 The name of your zone. This parameter cannot be empty.
21259 @item @code{ns} (default: @code{"ns"})
21260 The domain of your primary authoritative DNS server. The name is relative to
21261 the origin, unless it ends with a dot. It is mandatory that this primary
21262 DNS server corresponds to an NS record in the zone and that it is associated
21263 to an IP address in the list of entries.
21265 @item @code{mail} (default: @code{"hostmaster"})
21266 An email address people can contact you at, as the owner of the zone. This
21267 is translated as @code{<mail>@@<origin>}.
21269 @item @code{serial} (default: @code{1})
21270 The serial number of the zone. As this is used to keep track of changes by
21271 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
21272 Always increment it when you make a change in your zone.
21274 @item @code{refresh} (default: @code{(* 2 24 3600)})
21275 The frequency at which slaves will do a zone transfer. This value is a number
21276 of seconds. It can be computed by multiplications or with
21277 @code{(string->duration)}.
21279 @item @code{retry} (default: @code{(* 15 60)})
21280 The period after which a slave will retry to contact its master when it fails
21281 to do so a first time.
21283 @item @code{expiry} (default: @code{(* 14 24 3600)})
21284 Default TTL of records. Existing records are considered correct for at most
21285 this amount of time. After this period, resolvers will invalidate their cache
21286 and check again that it still exists.
21288 @item @code{nx} (default: @code{3600})
21289 Default TTL of inexistant records. This delay is usually short because you want
21290 your new domains to reach everyone quickly.
21295 @deftp {Data Type} knot-remote-configuration
21296 Data type representing a remote configuration.
21297 This type has the following parameters:
21300 @item @code{id} (default: @code{""})
21301 An identifier for other configuration fields to refer to this remote. IDs must
21302 be unique and must not be empty.
21304 @item @code{address} (default: @code{'()})
21305 An ordered list of destination IP addresses. Addresses are tried in sequence.
21306 An optional port can be given with the @@ separator. For instance:
21307 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
21309 @item @code{via} (default: @code{'()})
21310 An ordered list of source IP addresses. An empty list will have Knot choose
21311 an appropriate source IP. An optional port can be given with the @@ separator.
21312 The default is to choose at random.
21314 @item @code{key} (default: @code{#f})
21315 A reference to a key, that is a string containing the identifier of a key
21316 defined in a @code{knot-key-configuration} field.
21321 @deftp {Data Type} knot-keystore-configuration
21322 Data type representing a keystore to hold dnssec keys.
21323 This type has the following parameters:
21326 @item @code{id} (default: @code{""})
21327 The id of the keystore. It must not be empty.
21329 @item @code{backend} (default: @code{'pem})
21330 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
21332 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
21333 The configuration string of the backend. An example for the PKCS#11 is:
21334 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
21335 For the pem backend, the string represents a path in the file system.
21340 @deftp {Data Type} knot-policy-configuration
21341 Data type representing a dnssec policy. Knot DNS is able to automatically
21342 sign your zones. It can either generate and manage your keys automatically or
21343 use keys that you generate.
21345 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
21346 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
21347 zone. In order to be trusted, the KSK needs to be present in the parent zone
21348 (usually a top-level domain). If your registrar supports dnssec, you will
21349 have to send them your KSK's hash so they can add a DS record in their zone.
21350 This is not automated and need to be done each time you change your KSK.
21352 The policy also defines the lifetime of keys. Usually, ZSK can be changed
21353 easily and use weaker cryptographic functions (they use lower parameters) in
21354 order to sign records quickly, so they are changed often. The KSK however
21355 requires manual interaction with the registrar, so they are changed less often
21356 and use stronger parameters because they sign only one record.
21358 This type has the following parameters:
21361 @item @code{id} (default: @code{""})
21362 The id of the policy. It must not be empty.
21364 @item @code{keystore} (default: @code{"default"})
21365 A reference to a keystore, that is a string containing the identifier of a
21366 keystore defined in a @code{knot-keystore-configuration} field. The
21367 @code{"default"} identifier means the default keystore (a kasp database that
21368 was setup by this service).
21370 @item @code{manual?} (default: @code{#f})
21371 Whether the key management is manual or automatic.
21373 @item @code{single-type-signing?} (default: @code{#f})
21374 When @code{#t}, use the Single-Type Signing Scheme.
21376 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
21377 An algorithm of signing keys and issued signatures.
21379 @item @code{ksk-size} (default: @code{256})
21380 The length of the KSK. Note that this value is correct for the default
21381 algorithm, but would be unsecure for other algorithms.
21383 @item @code{zsk-size} (default: @code{256})
21384 The length of the ZSK. Note that this value is correct for the default
21385 algorithm, but would be unsecure for other algorithms.
21387 @item @code{dnskey-ttl} (default: @code{'default})
21388 The TTL value for DNSKEY records added into zone apex. The special
21389 @code{'default} value means same as the zone SOA TTL.
21391 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
21392 The period between ZSK publication and the next rollover initiation.
21394 @item @code{propagation-delay} (default: @code{(* 24 3600)})
21395 An extra delay added for each key rollover step. This value should be high
21396 enough to cover propagation of data from the master server to all slaves.
21398 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
21399 A validity period of newly issued signatures.
21401 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
21402 A period how long before a signature expiration the signature will be refreshed.
21404 @item @code{nsec3?} (default: @code{#f})
21405 When @code{#t}, NSEC3 will be used instead of NSEC.
21407 @item @code{nsec3-iterations} (default: @code{5})
21408 The number of additional times the hashing is performed.
21410 @item @code{nsec3-salt-length} (default: @code{8})
21411 The length of a salt field in octets, which is appended to the original owner
21412 name before hashing.
21414 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
21415 The validity period of newly issued salt field.
21420 @deftp {Data Type} knot-zone-configuration
21421 Data type representing a zone served by Knot.
21422 This type has the following parameters:
21425 @item @code{domain} (default: @code{""})
21426 The domain served by this configuration. It must not be empty.
21428 @item @code{file} (default: @code{""})
21429 The file where this zone is saved. This parameter is ignored by master zones.
21430 Empty means default location that depends on the domain name.
21432 @item @code{zone} (default: @code{(zone-file)})
21433 The content of the zone file. This parameter is ignored by slave zones. It
21434 must contain a zone-file record.
21436 @item @code{master} (default: @code{'()})
21437 A list of master remotes. When empty, this zone is a master. When set, this
21438 zone is a slave. This is a list of remotes identifiers.
21440 @item @code{ddns-master} (default: @code{#f})
21441 The main master. When empty, it defaults to the first master in the list of
21444 @item @code{notify} (default: @code{'()})
21445 A list of slave remote identifiers.
21447 @item @code{acl} (default: @code{'()})
21448 A list of acl identifiers.
21450 @item @code{semantic-checks?} (default: @code{#f})
21451 When set, this adds more semantic checks to the zone.
21453 @item @code{disable-any?} (default: @code{#f})
21454 When set, this forbids queries of the ANY type.
21456 @item @code{zonefile-sync} (default: @code{0})
21457 The delay between a modification in memory and on disk. 0 means immediate
21460 @item @code{zonefile-load} (default: @code{#f})
21461 The way the zone file contents are applied during zone load. Possible values
21465 @item @code{#f} for using the default value from Knot,
21466 @item @code{'none} for not using the zone file at all,
21467 @item @code{'difference} for computing the difference between already available
21468 contents and zone contents and applying it to the current zone contents,
21469 @item @code{'difference-no-serial} for the same as @code{'difference}, but
21470 ignoring the SOA serial in the zone file, while the server takes care of it
21472 @item @code{'whole} for loading zone contents from the zone file.
21475 @item @code{journal-content} (default: @code{#f})
21476 The way the journal is used to store zone and its changes. Possible values
21477 are @code{'none} to not use it at all, @code{'changes} to store changes and
21478 @code{'all} to store contents. @code{#f} does not set this option, so the
21479 default value from Knot is used.
21481 @item @code{max-journal-usage} (default: @code{#f})
21482 The maximum size for the journal on disk. @code{#f} does not set this option,
21483 so the default value from Knot is used.
21485 @item @code{max-journal-depth} (default: @code{#f})
21486 The maximum size of the history. @code{#f} does not set this option, so the
21487 default value from Knot is used.
21489 @item @code{max-zone-size} (default: @code{#f})
21490 The maximum size of the zone file. This limit is enforced for incoming
21491 transfer and updates. @code{#f} does not set this option, so the default
21492 value from Knot is used.
21494 @item @code{dnssec-policy} (default: @code{#f})
21495 A reference to a @code{knot-policy-configuration} record, or the special
21496 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
21499 @item @code{serial-policy} (default: @code{'increment})
21500 A policy between @code{'increment} and @code{'unixtime}.
21505 @deftp {Data Type} knot-configuration
21506 Data type representing the Knot configuration.
21507 This type has the following parameters:
21510 @item @code{knot} (default: @code{knot})
21513 @item @code{run-directory} (default: @code{"/var/run/knot"})
21514 The run directory. This directory will be used for pid file and sockets.
21516 @item @code{includes} (default: @code{'()})
21517 A list of strings or file-like objects denoting other files that must be
21518 included at the top of the configuration file.
21520 @cindex secrets, Knot service
21521 This can be used to manage secrets out-of-band. For example, secret
21522 keys may be stored in an out-of-band file not managed by Guix, and
21523 thus not visible in @file{/gnu/store}---e.g., you could store secret
21524 key configuration in @file{/etc/knot/secrets.conf} and add this file
21525 to the @code{includes} list.
21527 One can generate a secret tsig key (for nsupdate and zone transfers with the
21528 keymgr command from the knot package. Note that the package is not automatically
21529 installed by the service. The following example shows how to generate a new
21533 keymgr -t mysecret > /etc/knot/secrets.conf
21534 chmod 600 /etc/knot/secrets.conf
21537 Also note that the generated key will be named @var{mysecret}, so it is the
21538 name that needs to be used in the @var{key} field of the
21539 @code{knot-acl-configuration} record and in other places that need to refer
21542 It can also be used to add configuration not supported by this interface.
21544 @item @code{listen-v4} (default: @code{"0.0.0.0"})
21545 An ip address on which to listen.
21547 @item @code{listen-v6} (default: @code{"::"})
21548 An ip address on which to listen.
21550 @item @code{listen-port} (default: @code{53})
21551 A port on which to listen.
21553 @item @code{keys} (default: @code{'()})
21554 The list of knot-key-configuration used by this configuration.
21556 @item @code{acls} (default: @code{'()})
21557 The list of knot-acl-configuration used by this configuration.
21559 @item @code{remotes} (default: @code{'()})
21560 The list of knot-remote-configuration used by this configuration.
21562 @item @code{zones} (default: @code{'()})
21563 The list of knot-zone-configuration used by this configuration.
21568 @subsubheading Knot Resolver Service
21570 @deffn {Scheme Variable} knot-resolver-service-type
21571 This this the type of the knot resolver service, whose value should be
21572 an @code{knot-resolver-configuration} object as in this example:
21575 (service knot-resolver-service-type
21576 (knot-resolver-configuration
21577 (kresd-config-file (plain-file "kresd.conf" "
21578 net.listen('192.168.0.1', 5353)
21579 user('knot-resolver', 'knot-resolver')
21580 modules = @{ 'hints > iterate', 'stats', 'predict' @}
21581 cache.size = 100 * MB
21585 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
21588 @deftp {Data Type} knot-resolver-configuration
21589 Data type representing the configuration of knot-resolver.
21592 @item @code{package} (default: @var{knot-resolver})
21593 Package object of the knot DNS resolver.
21595 @item @code{kresd-config-file} (default: %kresd.conf)
21596 File-like object of the kresd configuration file to use, by default it
21597 will listen on @code{127.0.0.1} and @code{::1}.
21599 @item @code{garbage-collection-interval} (default: 1000)
21600 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
21606 @subsubheading Dnsmasq Service
21608 @deffn {Scheme Variable} dnsmasq-service-type
21609 This is the type of the dnsmasq service, whose value should be an
21610 @code{dnsmasq-configuration} object as in this example:
21613 (service dnsmasq-service-type
21614 (dnsmasq-configuration
21616 (servers '("192.168.1.1"))))
21620 @deftp {Data Type} dnsmasq-configuration
21621 Data type representing the configuration of dnsmasq.
21624 @item @code{package} (default: @var{dnsmasq})
21625 Package object of the dnsmasq server.
21627 @item @code{no-hosts?} (default: @code{#f})
21628 When true, don't read the hostnames in /etc/hosts.
21630 @item @code{port} (default: @code{53})
21631 The port to listen on. Setting this to zero completely disables DNS
21632 responses, leaving only DHCP and/or TFTP functions.
21634 @item @code{local-service?} (default: @code{#t})
21635 Accept DNS queries only from hosts whose address is on a local subnet,
21636 ie a subnet for which an interface exists on the server.
21638 @item @code{listen-addresses} (default: @code{'()})
21639 Listen on the given IP addresses.
21641 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
21642 The file to read the IP address of the upstream nameservers from.
21644 @item @code{no-resolv?} (default: @code{#f})
21645 When true, don't read @var{resolv-file}.
21647 @item @code{servers} (default: @code{'()})
21648 Specify IP address of upstream servers directly.
21650 @item @code{cache-size} (default: @code{150})
21651 Set the size of dnsmasq's cache. Setting the cache size to zero
21654 @item @code{negative-cache?} (default: @code{#t})
21655 When false, disable negative caching.
21660 @subsubheading ddclient Service
21663 The ddclient service described below runs the ddclient daemon, which takes
21664 care of automatically updating DNS entries for service providers such as
21665 @uref{https://dyn.com/dns/, Dyn}.
21667 The following example show instantiates the service with its default
21671 (service ddclient-service-type)
21674 Note that ddclient needs to access credentials that are stored in a
21675 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
21676 @code{secret-file} below.) You are expected to create this file manually, in
21677 an ``out-of-band'' fashion (you @emph{could} make this file part of the
21678 service configuration, for instance by using @code{plain-file}, but it will be
21679 world-readable @i{via} @file{/gnu/store}.) See the examples in the
21680 @file{share/ddclient} directory of the @code{ddclient} package.
21682 @c %start of fragment
21684 Available @code{ddclient-configuration} fields are:
21686 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
21687 The ddclient package.
21691 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
21692 The period after which ddclient will retry to check IP and domain name.
21694 Defaults to @samp{300}.
21698 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
21699 Use syslog for the output.
21701 Defaults to @samp{#t}.
21705 @deftypevr {@code{ddclient-configuration} parameter} string mail
21708 Defaults to @samp{"root"}.
21712 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
21713 Mail failed update to user.
21715 Defaults to @samp{"root"}.
21719 @deftypevr {@code{ddclient-configuration} parameter} string pid
21720 The ddclient PID file.
21722 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
21726 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
21727 Enable SSL support.
21729 Defaults to @samp{#t}.
21733 @deftypevr {@code{ddclient-configuration} parameter} string user
21734 Specifies the user name or ID that is used when running ddclient
21737 Defaults to @samp{"ddclient"}.
21741 @deftypevr {@code{ddclient-configuration} parameter} string group
21742 Group of the user who will run the ddclient program.
21744 Defaults to @samp{"ddclient"}.
21748 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
21749 Secret file which will be appended to @file{ddclient.conf} file. This
21750 file contains credentials for use by ddclient. You are expected to
21751 create it manually.
21753 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
21757 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
21758 Extra options will be appended to @file{ddclient.conf} file.
21760 Defaults to @samp{()}.
21765 @c %end of fragment
21769 @subsection VPN Services
21770 @cindex VPN (virtual private network)
21771 @cindex virtual private network (VPN)
21773 The @code{(gnu services vpn)} module provides services related to
21774 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
21775 your machine to connect to a VPN, and a @emph{server} service for your machine
21776 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
21778 @deffn {Scheme Procedure} openvpn-client-service @
21779 [#:config (openvpn-client-configuration)]
21781 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
21784 @deffn {Scheme Procedure} openvpn-server-service @
21785 [#:config (openvpn-server-configuration)]
21787 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
21789 Both can be run simultaneously.
21792 @c %automatically generated documentation
21794 Available @code{openvpn-client-configuration} fields are:
21796 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
21797 The OpenVPN package.
21801 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
21802 The OpenVPN pid file.
21804 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21808 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
21809 The protocol (UDP or TCP) used to open a channel between clients and
21812 Defaults to @samp{udp}.
21816 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
21817 The device type used to represent the VPN connection.
21819 Defaults to @samp{tun}.
21823 @deftypevr {@code{openvpn-client-configuration} parameter} string ca
21824 The certificate authority to check connections against.
21826 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21830 @deftypevr {@code{openvpn-client-configuration} parameter} string cert
21831 The certificate of the machine the daemon is running on. It should be
21832 signed by the authority given in @code{ca}.
21834 Defaults to @samp{"/etc/openvpn/client.crt"}.
21838 @deftypevr {@code{openvpn-client-configuration} parameter} string key
21839 The key of the machine the daemon is running on. It must be the key whose
21840 certificate is @code{cert}.
21842 Defaults to @samp{"/etc/openvpn/client.key"}.
21846 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
21847 Whether to use the lzo compression algorithm.
21849 Defaults to @samp{#t}.
21853 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
21854 Don't re-read key files across SIGUSR1 or --ping-restart.
21856 Defaults to @samp{#t}.
21860 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
21861 Don't close and reopen TUN/TAP device or run up/down scripts across
21862 SIGUSR1 or --ping-restart restarts.
21864 Defaults to @samp{#t}.
21868 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
21869 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
21870 poll/epoll/select prior to the write operation.
21872 Defaults to @samp{#f}.
21875 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
21878 Defaults to @samp{3}.
21882 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
21883 Add an additional layer of HMAC authentication on top of the TLS control
21884 channel to protect against DoS attacks.
21886 Defaults to @samp{#f}.
21890 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
21891 Authenticate with server using username/password. The option is a file
21892 containing username/password on 2 lines. Do not use a file-like object as it
21893 would be added to the store and readable by any user.
21895 Defaults to @samp{'disabled}.
21898 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
21899 Whether to check the server certificate has server usage extension.
21901 Defaults to @samp{#t}.
21905 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
21906 Bind to a specific local port number.
21908 Defaults to @samp{#f}.
21912 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
21913 Retry resolving server address.
21915 Defaults to @samp{#t}.
21919 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
21920 A list of remote servers to connect to.
21922 Defaults to @samp{()}.
21924 Available @code{openvpn-remote-configuration} fields are:
21926 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
21929 Defaults to @samp{"my-server"}.
21933 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
21934 Port number the server listens to.
21936 Defaults to @samp{1194}.
21941 @c %end of automatic openvpn-client documentation
21943 @c %automatically generated documentation
21945 Available @code{openvpn-server-configuration} fields are:
21947 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
21948 The OpenVPN package.
21952 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
21953 The OpenVPN pid file.
21955 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
21959 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
21960 The protocol (UDP or TCP) used to open a channel between clients and
21963 Defaults to @samp{udp}.
21967 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
21968 The device type used to represent the VPN connection.
21970 Defaults to @samp{tun}.
21974 @deftypevr {@code{openvpn-server-configuration} parameter} string ca
21975 The certificate authority to check connections against.
21977 Defaults to @samp{"/etc/openvpn/ca.crt"}.
21981 @deftypevr {@code{openvpn-server-configuration} parameter} string cert
21982 The certificate of the machine the daemon is running on. It should be
21983 signed by the authority given in @code{ca}.
21985 Defaults to @samp{"/etc/openvpn/client.crt"}.
21989 @deftypevr {@code{openvpn-server-configuration} parameter} string key
21990 The key of the machine the daemon is running on. It must be the key whose
21991 certificate is @code{cert}.
21993 Defaults to @samp{"/etc/openvpn/client.key"}.
21997 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
21998 Whether to use the lzo compression algorithm.
22000 Defaults to @samp{#t}.
22004 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
22005 Don't re-read key files across SIGUSR1 or --ping-restart.
22007 Defaults to @samp{#t}.
22011 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
22012 Don't close and reopen TUN/TAP device or run up/down scripts across
22013 SIGUSR1 or --ping-restart restarts.
22015 Defaults to @samp{#t}.
22019 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
22020 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
22021 poll/epoll/select prior to the write operation.
22023 Defaults to @samp{#f}.
22026 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
22029 Defaults to @samp{3}.
22033 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
22034 Add an additional layer of HMAC authentication on top of the TLS control
22035 channel to protect against DoS attacks.
22037 Defaults to @samp{#f}.
22041 @deftypevr {@code{openvpn-server-configuration} parameter} number port
22042 Specifies the port number on which the server listens.
22044 Defaults to @samp{1194}.
22048 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
22049 An ip and mask specifying the subnet inside the virtual network.
22051 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
22055 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
22056 A CIDR notation specifying the IPv6 subnet inside the virtual network.
22058 Defaults to @samp{#f}.
22062 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
22063 The Diffie-Hellman parameters file.
22065 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
22069 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
22070 The file that records client IPs.
22072 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
22076 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
22077 When true, the server will act as a gateway for its clients.
22079 Defaults to @samp{#f}.
22083 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
22084 When true, clients are allowed to talk to each other inside the VPN.
22086 Defaults to @samp{#f}.
22090 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
22091 Causes ping-like messages to be sent back and forth over the link so
22092 that each side knows when the other side has gone down. @code{keepalive}
22093 requires a pair. The first element is the period of the ping sending,
22094 and the second element is the timeout before considering the other side
22099 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
22100 The maximum number of clients.
22102 Defaults to @samp{100}.
22106 @deftypevr {@code{openvpn-server-configuration} parameter} string status
22107 The status file. This file shows a small report on current connection.
22108 It is truncated and rewritten every minute.
22110 Defaults to @samp{"/var/run/openvpn/status"}.
22114 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
22115 The list of configuration for some clients.
22117 Defaults to @samp{()}.
22119 Available @code{openvpn-ccd-configuration} fields are:
22121 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
22124 Defaults to @samp{"client"}.
22128 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
22131 Defaults to @samp{#f}.
22135 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
22138 Defaults to @samp{#f}.
22145 @c %end of automatic openvpn-server documentation
22148 @node Network File System
22149 @subsection Network File System
22152 The @code{(gnu services nfs)} module provides the following services,
22153 which are most commonly used in relation to mounting or exporting
22154 directory trees as @dfn{network file systems} (NFS).
22156 While it is possible to use the individual components that together make
22157 up a Network File System service, we recommended to configure an NFS
22158 server with the @code{nfs-service-type}.
22160 @subsubheading NFS Service
22161 @cindex NFS, server
22163 The NFS service takes care of setting up all NFS component services,
22164 kernel configuration file systems, and installs configuration files in
22165 the locations that NFS expects.
22167 @defvr {Scheme Variable} nfs-service-type
22168 A service type for a complete NFS server.
22171 @deftp {Data Type} nfs-configuration
22172 This data type represents the configuration of the NFS service and all
22175 It has the following parameters:
22177 @item @code{nfs-utils} (default: @code{nfs-utils})
22178 The nfs-utils package to use.
22180 @item @code{nfs-version} (default: @code{#f})
22181 If a string value is provided, the @command{rpc.nfsd} daemon will be
22182 limited to supporting the given version of the NFS protocol.
22184 @item @code{exports} (default: @code{'()})
22185 This is a list of directories the NFS server should export. Each entry
22186 is a list consisting of two elements: a directory name and a string
22187 containing all options. This is an example in which the directory
22188 @file{/export} is served to all NFS clients as a read-only share:
22194 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
22197 @item @code{rpcmountd-port} (default: @code{#f})
22198 The network port that the @command{rpc.mountd} daemon should use.
22200 @item @code{rpcstatd-port} (default: @code{#f})
22201 The network port that the @command{rpc.statd} daemon should use.
22203 @item @code{rpcbind} (default: @code{rpcbind})
22204 The rpcbind package to use.
22206 @item @code{idmap-domain} (default: @code{"localdomain"})
22207 The local NFSv4 domain name.
22209 @item @code{nfsd-port} (default: @code{2049})
22210 The network port that the @command{nfsd} daemon should use.
22212 @item @code{nfsd-threads} (default: @code{8})
22213 The number of threads used by the @command{nfsd} daemon.
22215 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22216 The directory where the pipefs file system is mounted.
22218 @item @code{debug} (default: @code{'()"})
22219 A list of subsystems for which debugging output should be enabled. This
22220 is a list of symbols. Any of these symbols are valid: @code{nfsd},
22221 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
22225 If you don't need a complete NFS service or prefer to build it yourself
22226 you can use the individual component services that are documented below.
22228 @subsubheading RPC Bind Service
22231 The RPC Bind service provides a facility to map program numbers into
22232 universal addresses.
22233 Many NFS related services use this facility. Hence it is automatically
22234 started when a dependent service starts.
22236 @defvr {Scheme Variable} rpcbind-service-type
22237 A service type for the RPC portmapper daemon.
22241 @deftp {Data Type} rpcbind-configuration
22242 Data type representing the configuration of the RPC Bind Service.
22243 This type has the following parameters:
22245 @item @code{rpcbind} (default: @code{rpcbind})
22246 The rpcbind package to use.
22248 @item @code{warm-start?} (default: @code{#t})
22249 If this parameter is @code{#t}, then the daemon will read a
22250 state file on startup thus reloading state information saved by a previous
22256 @subsubheading Pipefs Pseudo File System
22260 The pipefs file system is used to transfer NFS related data
22261 between the kernel and user space programs.
22263 @defvr {Scheme Variable} pipefs-service-type
22264 A service type for the pipefs pseudo file system.
22267 @deftp {Data Type} pipefs-configuration
22268 Data type representing the configuration of the pipefs pseudo file system service.
22269 This type has the following parameters:
22271 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22272 The directory to which the file system is to be attached.
22277 @subsubheading GSS Daemon Service
22280 @cindex global security system
22282 The @dfn{global security system} (GSS) daemon provides strong security for RPC
22284 Before exchanging RPC requests an RPC client must establish a security
22285 context. Typically this is done using the Kerberos command @command{kinit}
22286 or automatically at login time using PAM services (@pxref{Kerberos Services}).
22288 @defvr {Scheme Variable} gss-service-type
22289 A service type for the Global Security System (GSS) daemon.
22292 @deftp {Data Type} gss-configuration
22293 Data type representing the configuration of the GSS daemon service.
22294 This type has the following parameters:
22296 @item @code{nfs-utils} (default: @code{nfs-utils})
22297 The package in which the @command{rpc.gssd} command is to be found.
22299 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22300 The directory where the pipefs file system is mounted.
22306 @subsubheading IDMAP Daemon Service
22308 @cindex name mapper
22310 The idmap daemon service provides mapping between user IDs and user names.
22311 Typically it is required in order to access file systems mounted via NFSv4.
22313 @defvr {Scheme Variable} idmap-service-type
22314 A service type for the Identity Mapper (IDMAP) daemon.
22317 @deftp {Data Type} idmap-configuration
22318 Data type representing the configuration of the IDMAP daemon service.
22319 This type has the following parameters:
22321 @item @code{nfs-utils} (default: @code{nfs-utils})
22322 The package in which the @command{rpc.idmapd} command is to be found.
22324 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
22325 The directory where the pipefs file system is mounted.
22327 @item @code{domain} (default: @code{#f})
22328 The local NFSv4 domain name.
22329 This must be a string or @code{#f}.
22330 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
22332 @item @code{verbosity} (default: @code{0})
22333 The verbosity level of the daemon.
22338 @node Continuous Integration
22339 @subsection Continuous Integration
22341 @cindex continuous integration
22342 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
22343 continuous integration tool for Guix. It can be used both for development and
22344 for providing substitutes to others (@pxref{Substitutes}).
22346 The @code{(gnu services cuirass)} module provides the following service.
22348 @defvr {Scheme Procedure} cuirass-service-type
22349 The type of the Cuirass service. Its value must be a
22350 @code{cuirass-configuration} object, as described below.
22353 To add build jobs, you have to set the @code{specifications} field of the
22354 configuration. Here is an example of a service that polls the Guix repository
22355 and builds the packages from a manifest. Some of the packages are defined in
22356 the @code{"custom-packages"} input, which is the equivalent of
22357 @code{GUIX_PACKAGE_PATH}.
22360 (define %cuirass-specs
22362 '((#:name . "my-manifest")
22363 (#:load-path-inputs . ("guix"))
22364 (#:package-path-inputs . ("custom-packages"))
22365 (#:proc-input . "guix")
22366 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
22367 (#:proc . cuirass-jobs)
22368 (#:proc-args . ((subset . "manifests")
22369 (systems . ("x86_64-linux"))
22370 (manifests . (("config" . "guix/manifest.scm")))))
22371 (#:inputs . (((#:name . "guix")
22372 (#:url . "git://git.savannah.gnu.org/guix.git")
22373 (#:load-path . ".")
22374 (#:branch . "master")
22375 (#:no-compile? . #t))
22376 ((#:name . "config")
22377 (#:url . "https://git.example.org/config.git")
22378 (#:load-path . ".")
22379 (#:branch . "master")
22380 (#:no-compile? . #t))
22381 ((#:name . "custom-packages")
22382 (#:url . "https://git.example.org/custom-packages.git")
22383 (#:load-path . ".")
22384 (#:branch . "master")
22385 (#:no-compile? . #t)))))))
22387 (service cuirass-service-type
22388 (cuirass-configuration
22389 (specifications %cuirass-specs)))
22392 While information related to build jobs is located directly in the
22393 specifications, global settings for the @command{cuirass} process are
22394 accessible in other @code{cuirass-configuration} fields.
22396 @deftp {Data Type} cuirass-configuration
22397 Data type representing the configuration of Cuirass.
22400 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
22401 Location of the log file.
22403 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
22404 Location of the log file used by the web interface.
22406 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
22407 Location of the repository cache.
22409 @item @code{user} (default: @code{"cuirass"})
22410 Owner of the @code{cuirass} process.
22412 @item @code{group} (default: @code{"cuirass"})
22413 Owner's group of the @code{cuirass} process.
22415 @item @code{interval} (default: @code{60})
22416 Number of seconds between the poll of the repositories followed by the
22419 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
22420 Location of sqlite database which contains the build results and previously
22421 added specifications.
22423 @item @code{ttl} (default: @code{(* 30 24 3600)})
22424 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
22425 are registered for build results. This means that build results are protected
22426 from garbage collection for at least @var{ttl} seconds.
22428 @item @code{port} (default: @code{8081})
22429 Port number used by the HTTP server.
22431 @item @code{host} (default: @code{"localhost"})
22432 Listen on the network interface for @var{host}. The default is to
22433 accept connections from localhost.
22435 @item @code{specifications} (default: @code{#~'()})
22436 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
22437 where a specification is an association list
22438 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
22439 keys are keywords (@code{#:keyword-example}) as shown in the example
22442 @item @code{use-substitutes?} (default: @code{#f})
22443 This allows using substitutes to avoid building every dependencies of a job
22446 @item @code{one-shot?} (default: @code{#f})
22447 Only evaluate specifications and build derivations once.
22449 @item @code{fallback?} (default: @code{#f})
22450 When substituting a pre-built binary fails, fall back to building
22453 @item @code{cuirass} (default: @code{cuirass})
22454 The Cuirass package to use.
22458 @node Power Management Services
22459 @subsection Power Management Services
22462 @cindex power management with TLP
22463 @subsubheading TLP daemon
22465 The @code{(gnu services pm)} module provides a Guix service definition
22466 for the Linux power management tool TLP.
22468 TLP enables various powersaving modes in userspace and kernel.
22469 Contrary to @code{upower-service}, it is not a passive,
22470 monitoring tool, as it will apply custom settings each time a new power
22471 source is detected. More information can be found at
22472 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
22474 @deffn {Scheme Variable} tlp-service-type
22475 The service type for the TLP tool. Its value should be a valid
22476 TLP configuration (see below). To use the default settings, simply
22479 (service tlp-service-type)
22483 By default TLP does not need much configuration but most TLP parameters
22484 can be tweaked using @code{tlp-configuration}.
22486 Each parameter definition is preceded by its type; for example,
22487 @samp{boolean foo} indicates that the @code{foo} parameter
22488 should be specified as a boolean. Types starting with
22489 @code{maybe-} denote parameters that won't show up in TLP config file
22490 when their value is @code{'disabled}.
22492 @c The following documentation was initially generated by
22493 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
22494 @c documentation is better, so we shouldn't hesitate to edit below as
22495 @c needed. However if the change you want to make to this documentation
22496 @c can be done in an automated way, it's probably easier to change
22497 @c (generate-documentation) than to make it below and have to deal with
22498 @c the churn as TLP updates.
22500 Available @code{tlp-configuration} fields are:
22502 @deftypevr {@code{tlp-configuration} parameter} package tlp
22507 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
22508 Set to true if you wish to enable TLP.
22510 Defaults to @samp{#t}.
22514 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
22515 Default mode when no power supply can be detected. Alternatives are AC
22518 Defaults to @samp{"AC"}.
22522 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
22523 Number of seconds Linux kernel has to wait after the disk goes idle,
22524 before syncing on AC.
22526 Defaults to @samp{0}.
22530 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
22531 Same as @code{disk-idle-ac} but on BAT mode.
22533 Defaults to @samp{2}.
22537 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
22538 Dirty pages flushing periodicity, expressed in seconds.
22540 Defaults to @samp{15}.
22544 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
22545 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
22547 Defaults to @samp{60}.
22551 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
22552 CPU frequency scaling governor on AC mode. With intel_pstate driver,
22553 alternatives are powersave and performance. With acpi-cpufreq driver,
22554 alternatives are ondemand, powersave, performance and conservative.
22556 Defaults to @samp{disabled}.
22560 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
22561 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
22563 Defaults to @samp{disabled}.
22567 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
22568 Set the min available frequency for the scaling governor on AC.
22570 Defaults to @samp{disabled}.
22574 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
22575 Set the max available frequency for the scaling governor on AC.
22577 Defaults to @samp{disabled}.
22581 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
22582 Set the min available frequency for the scaling governor on BAT.
22584 Defaults to @samp{disabled}.
22588 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
22589 Set the max available frequency for the scaling governor on BAT.
22591 Defaults to @samp{disabled}.
22595 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
22596 Limit the min P-state to control the power dissipation of the CPU, in AC
22597 mode. Values are stated as a percentage of the available performance.
22599 Defaults to @samp{disabled}.
22603 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
22604 Limit the max P-state to control the power dissipation of the CPU, in AC
22605 mode. Values are stated as a percentage of the available performance.
22607 Defaults to @samp{disabled}.
22611 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
22612 Same as @code{cpu-min-perf-on-ac} on BAT mode.
22614 Defaults to @samp{disabled}.
22618 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
22619 Same as @code{cpu-max-perf-on-ac} on BAT mode.
22621 Defaults to @samp{disabled}.
22625 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
22626 Enable CPU turbo boost feature on AC mode.
22628 Defaults to @samp{disabled}.
22632 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
22633 Same as @code{cpu-boost-on-ac?} on BAT mode.
22635 Defaults to @samp{disabled}.
22639 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
22640 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
22641 used under light load conditions.
22643 Defaults to @samp{#f}.
22647 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
22648 Same as @code{sched-powersave-on-ac?} but on BAT mode.
22650 Defaults to @samp{#t}.
22654 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
22655 Enable Linux kernel NMI watchdog.
22657 Defaults to @samp{#f}.
22661 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
22662 For Linux kernels with PHC patch applied, change CPU voltages. An
22663 example value would be @samp{"F:V F:V F:V F:V"}.
22665 Defaults to @samp{disabled}.
22669 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
22670 Set CPU performance versus energy saving policy on AC. Alternatives are
22671 performance, normal, powersave.
22673 Defaults to @samp{"performance"}.
22677 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
22678 Same as @code{energy-perf-policy-ac} but on BAT mode.
22680 Defaults to @samp{"powersave"}.
22684 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
22689 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
22690 Hard disk advanced power management level.
22694 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
22695 Same as @code{disk-apm-bat} but on BAT mode.
22699 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
22700 Hard disk spin down timeout. One value has to be specified for each
22701 declared hard disk.
22703 Defaults to @samp{disabled}.
22707 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
22708 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
22710 Defaults to @samp{disabled}.
22714 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
22715 Select IO scheduler for disk devices. One value has to be specified for
22716 each declared hard disk. Example alternatives are cfq, deadline and
22719 Defaults to @samp{disabled}.
22723 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
22724 SATA aggressive link power management (ALPM) level. Alternatives are
22725 min_power, medium_power, max_performance.
22727 Defaults to @samp{"max_performance"}.
22731 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
22732 Same as @code{sata-linkpwr-ac} but on BAT mode.
22734 Defaults to @samp{"min_power"}.
22738 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
22739 Exclude specified SATA host devices for link power management.
22741 Defaults to @samp{disabled}.
22745 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
22746 Enable Runtime Power Management for AHCI controller and disks on AC
22749 Defaults to @samp{disabled}.
22753 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
22754 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
22756 Defaults to @samp{disabled}.
22760 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
22761 Seconds of inactivity before disk is suspended.
22763 Defaults to @samp{15}.
22767 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
22768 PCI Express Active State Power Management level. Alternatives are
22769 default, performance, powersave.
22771 Defaults to @samp{"performance"}.
22775 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
22776 Same as @code{pcie-aspm-ac} but on BAT mode.
22778 Defaults to @samp{"powersave"}.
22782 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
22783 Radeon graphics clock speed level. Alternatives are low, mid, high,
22786 Defaults to @samp{"high"}.
22790 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
22791 Same as @code{radeon-power-ac} but on BAT mode.
22793 Defaults to @samp{"low"}.
22797 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
22798 Radeon dynamic power management method (DPM). Alternatives are battery,
22801 Defaults to @samp{"performance"}.
22805 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
22806 Same as @code{radeon-dpm-state-ac} but on BAT mode.
22808 Defaults to @samp{"battery"}.
22812 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
22813 Radeon DPM performance level. Alternatives are auto, low, high.
22815 Defaults to @samp{"auto"}.
22819 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
22820 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
22822 Defaults to @samp{"auto"}.
22826 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
22827 Wifi power saving mode.
22829 Defaults to @samp{#f}.
22833 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
22834 Same as @code{wifi-power-ac?} but on BAT mode.
22836 Defaults to @samp{#t}.
22840 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
22841 Disable wake on LAN.
22843 Defaults to @samp{#t}.
22847 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
22848 Timeout duration in seconds before activating audio power saving on
22849 Intel HDA and AC97 devices. A value of 0 disables power saving.
22851 Defaults to @samp{0}.
22855 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
22856 Same as @code{sound-powersave-ac} but on BAT mode.
22858 Defaults to @samp{1}.
22862 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
22863 Disable controller in powersaving mode on Intel HDA devices.
22865 Defaults to @samp{#t}.
22869 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
22870 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
22871 powered on again by releasing (and reinserting) the eject lever or by
22872 pressing the disc eject button on newer models.
22874 Defaults to @samp{#f}.
22878 @deftypevr {@code{tlp-configuration} parameter} string bay-device
22879 Name of the optical drive device to power off.
22881 Defaults to @samp{"sr0"}.
22885 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
22886 Runtime Power Management for PCI(e) bus devices. Alternatives are on
22889 Defaults to @samp{"on"}.
22893 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
22894 Same as @code{runtime-pm-ac} but on BAT mode.
22896 Defaults to @samp{"auto"}.
22900 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
22901 Runtime Power Management for all PCI(e) bus devices, except blacklisted
22904 Defaults to @samp{#t}.
22908 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
22909 Exclude specified PCI(e) device addresses from Runtime Power Management.
22911 Defaults to @samp{disabled}.
22915 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
22916 Exclude PCI(e) devices assigned to the specified drivers from Runtime
22921 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
22922 Enable USB autosuspend feature.
22924 Defaults to @samp{#t}.
22928 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
22929 Exclude specified devices from USB autosuspend.
22931 Defaults to @samp{disabled}.
22935 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
22936 Exclude WWAN devices from USB autosuspend.
22938 Defaults to @samp{#t}.
22942 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
22943 Include specified devices into USB autosuspend, even if they are already
22944 excluded by the driver or via @code{usb-blacklist-wwan?}.
22946 Defaults to @samp{disabled}.
22950 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
22951 Enable USB autosuspend before shutdown.
22953 Defaults to @samp{disabled}.
22957 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
22958 Restore radio device state (bluetooth, wifi, wwan) from previous
22959 shutdown on system startup.
22961 Defaults to @samp{#f}.
22966 @cindex CPU frequency scaling with thermald
22967 @subsubheading Thermald daemon
22969 The @code{(gnu services pm)} module provides an interface to
22970 thermald, a CPU frequency scaling service which helps prevent overheating.
22972 @defvr {Scheme Variable} thermald-service-type
22973 This is the service type for
22974 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
22975 Thermal Daemon, which is responsible for controlling the thermal state
22976 of processors and preventing overheating.
22979 @deftp {Data Type} thermald-configuration
22980 Data type representing the configuration of @code{thermald-service-type}.
22983 @item @code{ignore-cpuid-check?} (default: @code{#f})
22984 Ignore cpuid check for supported CPU models.
22986 @item @code{thermald} (default: @var{thermald})
22987 Package object of thermald.
22992 @node Audio Services
22993 @subsection Audio Services
22995 The @code{(gnu services audio)} module provides a service to start MPD
22996 (the Music Player Daemon).
22999 @subsubheading Music Player Daemon
23001 The Music Player Daemon (MPD) is a service that can play music while
23002 being controlled from the local machine or over the network by a variety
23005 The following example shows how one might run @code{mpd} as user
23006 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
23009 (service mpd-service-type
23015 @defvr {Scheme Variable} mpd-service-type
23016 The service type for @command{mpd}
23019 @deftp {Data Type} mpd-configuration
23020 Data type representing the configuration of @command{mpd}.
23023 @item @code{user} (default: @code{"mpd"})
23024 The user to run mpd as.
23026 @item @code{music-dir} (default: @code{"~/Music"})
23027 The directory to scan for music files.
23029 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
23030 The directory to store playlists.
23032 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
23033 The location of the music database.
23035 @item @code{state-file} (default: @code{"~/.mpd/state"})
23036 The location of the file that stores current MPD's state.
23038 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
23039 The location of the sticker database.
23041 @item @code{port} (default: @code{"6600"})
23042 The port to run mpd on.
23044 @item @code{address} (default: @code{"any"})
23045 The address that mpd will bind to. To use a Unix domain socket,
23046 an absolute path can be specified here.
23048 @item @code{outputs} (default: @code{"(list (mpd-output))"})
23049 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
23054 @deftp {Data Type} mpd-output
23055 Data type representing an @command{mpd} audio output.
23058 @item @code{name} (default: @code{"MPD"})
23059 The name of the audio output.
23061 @item @code{type} (default: @code{"pulse"})
23062 The type of audio output.
23064 @item @code{enabled?} (default: @code{#t})
23065 Specifies whether this audio output is enabled when MPD is started. By
23066 default, all audio outputs are enabled. This is just the default
23067 setting when there is no state file; with a state file, the previous
23070 @item @code{tags?} (default: @code{#t})
23071 If set to @code{#f}, then MPD will not send tags to this output. This
23072 is only useful for output plugins that can receive tags, for example the
23073 @code{httpd} output plugin.
23075 @item @code{always-on?} (default: @code{#f})
23076 If set to @code{#t}, then MPD attempts to keep this audio output always
23077 open. This may be useful for streaming servers, when you don’t want to
23078 disconnect all listeners even when playback is accidentally stopped.
23080 @item @code{mixer-type}
23081 This field accepts a symbol that specifies which mixer should be used
23082 for this audio output: the @code{hardware} mixer, the @code{software}
23083 mixer, the @code{null} mixer (allows setting the volume, but with no
23084 effect; this can be used as a trick to implement an external mixer
23085 External Mixer) or no mixer (@code{none}).
23087 @item @code{extra-options} (default: @code{'()"})
23088 An association list of option symbols to string values to be appended to
23089 the audio output configuration.
23094 The following example shows a configuration of @code{mpd} that provides
23095 an HTTP audio streaming output.
23098 (service mpd-service-type
23106 `((encoder . "vorbis")
23107 (port . "8080"))))))))
23111 @node Virtualization Services
23112 @subsection Virtualization services
23114 The @code{(gnu services virtualization)} module provides services for
23115 the libvirt and virtlog daemons, as well as other virtualization-related
23118 @subsubheading Libvirt daemon
23119 @code{libvirtd} is the server side daemon component of the libvirt
23120 virtualization management system. This daemon runs on host servers
23121 and performs required management tasks for virtualized guests.
23123 @deffn {Scheme Variable} libvirt-service-type
23124 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
23125 Its value must be a @code{libvirt-configuration}.
23128 (service libvirt-service-type
23129 (libvirt-configuration
23130 (unix-sock-group "libvirt")
23131 (tls-port "16555")))
23135 @c Auto-generated with (generate-libvirt-documentation)
23136 Available @code{libvirt-configuration} fields are:
23138 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
23143 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
23144 Flag listening for secure TLS connections on the public TCP/IP port.
23145 must set @code{listen} for this to have any effect.
23147 It is necessary to setup a CA and issue server certificates before using
23150 Defaults to @samp{#t}.
23154 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
23155 Listen for unencrypted TCP connections on the public TCP/IP port. must
23156 set @code{listen} for this to have any effect.
23158 Using the TCP socket requires SASL authentication by default. Only SASL
23159 mechanisms which support data encryption are allowed. This is
23160 DIGEST_MD5 and GSSAPI (Kerberos5)
23162 Defaults to @samp{#f}.
23166 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
23167 Port for accepting secure TLS connections This can be a port number, or
23170 Defaults to @samp{"16514"}.
23174 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
23175 Port for accepting insecure TCP connections This can be a port number,
23178 Defaults to @samp{"16509"}.
23182 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
23183 IP address or hostname used for client connections.
23185 Defaults to @samp{"0.0.0.0"}.
23189 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
23190 Flag toggling mDNS advertisement of the libvirt service.
23192 Alternatively can disable for all services on a host by stopping the
23195 Defaults to @samp{#f}.
23199 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
23200 Default mDNS advertisement name. This must be unique on the immediate
23203 Defaults to @samp{"Virtualization Host <hostname>"}.
23207 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
23208 UNIX domain socket group ownership. This can be used to allow a
23209 'trusted' set of users access to management capabilities without
23212 Defaults to @samp{"root"}.
23216 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
23217 UNIX socket permissions for the R/O socket. This is used for monitoring
23220 Defaults to @samp{"0777"}.
23224 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
23225 UNIX socket permissions for the R/W socket. Default allows only root.
23226 If PolicyKit is enabled on the socket, the default will change to allow
23227 everyone (eg, 0777)
23229 Defaults to @samp{"0770"}.
23233 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
23234 UNIX socket permissions for the admin socket. Default allows only owner
23235 (root), do not change it unless you are sure to whom you are exposing
23238 Defaults to @samp{"0777"}.
23242 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
23243 The directory in which sockets will be found/created.
23245 Defaults to @samp{"/var/run/libvirt"}.
23249 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
23250 Authentication scheme for UNIX read-only sockets. By default socket
23251 permissions allow anyone to connect
23253 Defaults to @samp{"polkit"}.
23257 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
23258 Authentication scheme for UNIX read-write sockets. By default socket
23259 permissions only allow root. If PolicyKit support was compiled into
23260 libvirt, the default will be to use 'polkit' auth.
23262 Defaults to @samp{"polkit"}.
23266 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
23267 Authentication scheme for TCP sockets. If you don't enable SASL, then
23268 all TCP traffic is cleartext. Don't do this outside of a dev/test
23271 Defaults to @samp{"sasl"}.
23275 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
23276 Authentication scheme for TLS sockets. TLS sockets already have
23277 encryption provided by the TLS layer, and limited authentication is done
23280 It is possible to make use of any SASL authentication mechanism as well,
23281 by using 'sasl' for this option
23283 Defaults to @samp{"none"}.
23287 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
23288 API access control scheme.
23290 By default an authenticated user is allowed access to all APIs. Access
23291 drivers can place restrictions on this.
23293 Defaults to @samp{()}.
23297 @deftypevr {@code{libvirt-configuration} parameter} string key-file
23298 Server key file path. If set to an empty string, then no private key is
23301 Defaults to @samp{""}.
23305 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
23306 Server key file path. If set to an empty string, then no certificate is
23309 Defaults to @samp{""}.
23313 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
23314 Server key file path. If set to an empty string, then no CA certificate
23317 Defaults to @samp{""}.
23321 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
23322 Certificate revocation list path. If set to an empty string, then no
23325 Defaults to @samp{""}.
23329 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
23330 Disable verification of our own server certificates.
23332 When libvirtd starts it performs some sanity checks against its own
23335 Defaults to @samp{#f}.
23339 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
23340 Disable verification of client certificates.
23342 Client certificate verification is the primary authentication mechanism.
23343 Any client which does not present a certificate signed by the CA will be
23346 Defaults to @samp{#f}.
23350 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
23351 Whitelist of allowed x509 Distinguished Name.
23353 Defaults to @samp{()}.
23357 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
23358 Whitelist of allowed SASL usernames. The format for username depends on
23359 the SASL authentication mechanism.
23361 Defaults to @samp{()}.
23365 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
23366 Override the compile time default TLS priority string. The default is
23367 usually "NORMAL" unless overridden at build time. Only set this is it
23368 is desired for libvirt to deviate from the global default settings.
23370 Defaults to @samp{"NORMAL"}.
23374 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
23375 Maximum number of concurrent client connections to allow over all
23378 Defaults to @samp{5000}.
23382 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
23383 Maximum length of queue of connections waiting to be accepted by the
23384 daemon. Note, that some protocols supporting retransmission may obey
23385 this so that a later reattempt at connection succeeds.
23387 Defaults to @samp{1000}.
23391 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
23392 Maximum length of queue of accepted but not yet authenticated clients.
23393 Set this to zero to turn this feature off
23395 Defaults to @samp{20}.
23399 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
23400 Number of workers to start up initially.
23402 Defaults to @samp{5}.
23406 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
23407 Maximum number of worker threads.
23409 If the number of active clients exceeds @code{min-workers}, then more
23410 threads are spawned, up to max_workers limit. Typically you'd want
23411 max_workers to equal maximum number of clients allowed.
23413 Defaults to @samp{20}.
23417 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
23418 Number of priority workers. If all workers from above pool are stuck,
23419 some calls marked as high priority (notably domainDestroy) can be
23420 executed in this pool.
23422 Defaults to @samp{5}.
23426 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
23427 Total global limit on concurrent RPC calls.
23429 Defaults to @samp{20}.
23433 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
23434 Limit on concurrent requests from a single client connection. To avoid
23435 one client monopolizing the server this should be a small fraction of
23436 the global max_requests and max_workers parameter.
23438 Defaults to @samp{5}.
23442 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
23443 Same as @code{min-workers} but for the admin interface.
23445 Defaults to @samp{1}.
23449 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
23450 Same as @code{max-workers} but for the admin interface.
23452 Defaults to @samp{5}.
23456 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
23457 Same as @code{max-clients} but for the admin interface.
23459 Defaults to @samp{5}.
23463 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
23464 Same as @code{max-queued-clients} but for the admin interface.
23466 Defaults to @samp{5}.
23470 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
23471 Same as @code{max-client-requests} but for the admin interface.
23473 Defaults to @samp{5}.
23477 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
23478 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
23480 Defaults to @samp{3}.
23484 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
23487 A filter allows to select a different logging level for a given category
23488 of logs The format for a filter is one of:
23499 where @code{name} is a string which is matched against the category
23500 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
23501 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
23502 be a substring of the full category name, in order to match multiple
23503 similar categories), the optional "+" prefix tells libvirt to log stack
23504 trace for each message matching name, and @code{x} is the minimal level
23505 where matching messages should be logged:
23522 Multiple filters can be defined in a single filters statement, they just
23523 need to be separated by spaces.
23525 Defaults to @samp{"3:remote 4:event"}.
23529 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
23532 An output is one of the places to save logging information. The format
23533 for an output can be:
23537 output goes to stderr
23539 @item x:syslog:name
23540 use syslog for the output and use the given name as the ident
23542 @item x:file:file_path
23543 output to a file, with the given filepath
23546 output to journald logging system
23550 In all case the x prefix is the minimal level, acting as a filter
23567 Multiple outputs can be defined, they just need to be separated by
23570 Defaults to @samp{"3:stderr"}.
23574 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
23575 Allows usage of the auditing subsystem to be altered
23579 0: disable all auditing
23582 1: enable auditing, only if enabled on host
23585 2: enable auditing, and exit if disabled on host.
23589 Defaults to @samp{1}.
23593 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
23594 Send audit messages via libvirt logging infrastructure.
23596 Defaults to @samp{#f}.
23600 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
23601 Host UUID. UUID must not have all digits be the same.
23603 Defaults to @samp{""}.
23607 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
23608 Source to read host UUID.
23612 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
23615 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
23619 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
23622 Defaults to @samp{"smbios"}.
23626 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
23627 A keepalive message is sent to a client after @code{keepalive_interval}
23628 seconds of inactivity to check if the client is still responding. If
23629 set to -1, libvirtd will never send keepalive requests; however clients
23630 can still send them and the daemon will send responses.
23632 Defaults to @samp{5}.
23636 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
23637 Maximum number of keepalive messages that are allowed to be sent to the
23638 client without getting any response before the connection is considered
23641 In other words, the connection is automatically closed approximately
23642 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
23643 the last message received from the client. When @code{keepalive-count}
23644 is set to 0, connections will be automatically closed after
23645 @code{keepalive-interval} seconds of inactivity without sending any
23646 keepalive messages.
23648 Defaults to @samp{5}.
23652 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
23653 Same as above but for admin interface.
23655 Defaults to @samp{5}.
23659 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
23660 Same as above but for admin interface.
23662 Defaults to @samp{5}.
23666 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
23667 Timeout for Open vSwitch calls.
23669 The @code{ovs-vsctl} utility is used for the configuration and its
23670 timeout option is set by default to 5 seconds to avoid potential
23671 infinite waits blocking libvirt.
23673 Defaults to @samp{5}.
23677 @c %end of autogenerated docs
23679 @subsubheading Virtlog daemon
23680 The virtlogd service is a server side daemon component of libvirt that is
23681 used to manage logs from virtual machine consoles.
23683 This daemon is not used directly by libvirt client applications, rather it
23684 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
23685 standalone daemon, the main @code{libvirtd} daemon can be restarted without
23686 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
23687 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
23689 @deffn {Scheme Variable} virtlog-service-type
23690 This is the type of the virtlog daemon.
23691 Its value must be a @code{virtlog-configuration}.
23694 (service virtlog-service-type
23695 (virtlog-configuration
23696 (max-clients 1000)))
23700 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
23701 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
23703 Defaults to @samp{3}.
23707 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
23710 A filter allows to select a different logging level for a given category
23711 of logs The format for a filter is one of:
23722 where @code{name} is a string which is matched against the category
23723 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
23724 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
23725 be a substring of the full category name, in order to match multiple
23726 similar categories), the optional "+" prefix tells libvirt to log stack
23727 trace for each message matching name, and @code{x} is the minimal level
23728 where matching messages should be logged:
23745 Multiple filters can be defined in a single filters statement, they just
23746 need to be separated by spaces.
23748 Defaults to @samp{"3:remote 4:event"}.
23752 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
23755 An output is one of the places to save logging information The format
23756 for an output can be:
23760 output goes to stderr
23762 @item x:syslog:name
23763 use syslog for the output and use the given name as the ident
23765 @item x:file:file_path
23766 output to a file, with the given filepath
23769 output to journald logging system
23773 In all case the x prefix is the minimal level, acting as a filter
23790 Multiple outputs can be defined, they just need to be separated by
23793 Defaults to @samp{"3:stderr"}.
23797 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
23798 Maximum number of concurrent client connections to allow over all
23801 Defaults to @samp{1024}.
23805 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
23806 Maximum file size before rolling over.
23808 Defaults to @samp{2MB}
23812 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
23813 Maximum number of backup files to keep.
23815 Defaults to @samp{3}
23819 @subsubheading Transparent Emulation with QEMU
23822 @cindex @code{binfmt_misc}
23823 @code{qemu-binfmt-service-type} provides support for transparent
23824 emulation of program binaries built for different architectures---e.g.,
23825 it allows you to transparently execute an ARMv7 program on an x86_64
23826 machine. It achieves this by combining the @uref{https://www.qemu.org,
23827 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
23829 @defvr {Scheme Variable} qemu-binfmt-service-type
23830 This is the type of the QEMU/binfmt service for transparent emulation.
23831 Its value must be a @code{qemu-binfmt-configuration} object, which
23832 specifies the QEMU package to use as well as the architecture we want to
23836 (service qemu-binfmt-service-type
23837 (qemu-binfmt-configuration
23838 (platforms (lookup-qemu-platforms "arm" "aarch64" "mips64el"))))
23841 In this example, we enable transparent emulation for the ARM and aarch64
23842 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
23843 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
23844 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
23847 @deftp {Data Type} qemu-binfmt-configuration
23848 This is the configuration for the @code{qemu-binfmt} service.
23851 @item @code{platforms} (default: @code{'()})
23852 The list of emulated QEMU platforms. Each item must be a @dfn{platform
23853 object} as returned by @code{lookup-qemu-platforms} (see below).
23855 @item @code{guix-support?} (default: @code{#f})
23856 When it is true, QEMU and all its dependencies are added to the build
23857 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
23858 @code{--chroot-directory} option}). This allows the @code{binfmt_misc}
23859 handlers to be used within the build environment, which in turn means
23860 that you can transparently build programs for another architecture.
23862 For example, let's suppose you're on an x86_64 machine and you have this
23866 (service qemu-binfmt-service-type
23867 (qemu-binfmt-configuration
23868 (platforms (lookup-qemu-platforms "arm"))
23869 (guix-support? #t)))
23875 guix build -s armhf-linux inkscape
23879 and it will build Inkscape for ARMv7 @emph{as if it were a native
23880 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
23881 if you'd like to test a package build for an architecture you don't have
23884 @item @code{qemu} (default: @code{qemu})
23885 The QEMU package to use.
23889 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
23890 Return the list of QEMU platform objects corresponding to
23891 @var{platforms}@dots{}. @var{platforms} must be a list of strings
23892 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
23893 @code{"mips64el"}, and so on.
23896 @deffn {Scheme Procedure} qemu-platform? @var{obj}
23897 Return true if @var{obj} is a platform object.
23900 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
23901 Return the name of @var{platform}---a string such as @code{"arm"}.
23904 @node Version Control Services
23905 @subsection Version Control Services
23907 The @code{(gnu services version-control)} module provides a service to
23908 allow remote access to local Git repositories. There are three options:
23909 the @code{git-daemon-service}, which provides access to repositories via
23910 the @code{git://} unsecured TCP-based protocol, extending the
23911 @code{nginx} web server to proxy some requests to
23912 @code{git-http-backend}, or providing a web interface with
23913 @code{cgit-service-type}.
23915 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
23917 Return a service that runs @command{git daemon}, a simple TCP server to
23918 expose repositories over the Git protocol for anonymous access.
23920 The optional @var{config} argument should be a
23921 @code{<git-daemon-configuration>} object, by default it allows read-only
23922 access to exported@footnote{By creating the magic file
23923 "git-daemon-export-ok" in the repository directory.} repositories under
23928 @deftp {Data Type} git-daemon-configuration
23929 Data type representing the configuration for @code{git-daemon-service}.
23932 @item @code{package} (default: @var{git})
23933 Package object of the Git distributed version control system.
23935 @item @code{export-all?} (default: @var{#f})
23936 Whether to allow access for all Git repositories, even if they do not
23937 have the @file{git-daemon-export-ok} file.
23939 @item @code{base-path} (default: @file{/srv/git})
23940 Whether to remap all the path requests as relative to the given path.
23941 If you run git daemon with @var{(base-path "/srv/git")} on example.com,
23942 then if you later try to pull @code{git://example.com/hello.git}, git
23943 daemon will interpret the path as @code{/srv/git/hello.git}.
23945 @item @code{user-path} (default: @var{#f})
23946 Whether to allow @code{~user} notation to be used in requests. When
23947 specified with empty string, requests to @code{git://host/~alice/foo} is
23948 taken as a request to access @code{foo} repository in the home directory
23949 of user @code{alice}. If @var{(user-path "path")} is specified, the
23950 same request is taken as a request to access @code{path/foo} repository
23951 in the home directory of user @code{alice}.
23953 @item @code{listen} (default: @var{'()})
23954 Whether to listen on specific IP addresses or hostnames, defaults to
23957 @item @code{port} (default: @var{#f})
23958 Whether to listen on an alternative port, which defaults to 9418.
23960 @item @code{whitelist} (default: @var{'()})
23961 If not empty, only allow access to this list of directories.
23963 @item @code{extra-options} (default: @var{'()})
23964 Extra options will be passed to @code{git daemon}, please run
23965 @command{man git-daemon} for more information.
23970 The @code{git://} protocol lacks authentication. When you pull from a
23971 repository fetched via @code{git://}, you don't know whether the data you
23972 receive was modified or is even coming from the specified host, and your
23973 connection is subject to eavesdropping. It's better to use an authenticated
23974 and encrypted transport, such as @code{https}. Although Git allows you
23975 to serve repositories using unsophisticated file-based web servers,
23976 there is a faster protocol implemented by the @code{git-http-backend}
23977 program. This program is the back-end of a proper Git web service. It
23978 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
23979 on running the necessary @code{fcgiwrap} daemon.
23981 Guix has a separate configuration data type for serving Git repositories
23984 @deftp {Data Type} git-http-configuration
23985 Data type representing the configuration for @code{git-http-service}.
23988 @item @code{package} (default: @var{git})
23989 Package object of the Git distributed version control system.
23991 @item @code{git-root} (default: @file{/srv/git})
23992 Directory containing the Git repositories to expose to the world.
23994 @item @code{export-all?} (default: @var{#f})
23995 Whether to expose access for all Git repositories in @var{git-root},
23996 even if they do not have the @file{git-daemon-export-ok} file.
23998 @item @code{uri-path} (default: @file{/git/})
23999 Path prefix for Git access. With the default @code{/git/} prefix, this
24000 will map @code{http://@var{server}/git/@var{repo}.git} to
24001 @code{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
24002 with this prefix are not passed on to this Git instance.
24004 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
24005 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
24010 There is no @code{git-http-service-type}, currently; instead you can
24011 create an @code{nginx-location-configuration} from a
24012 @code{git-http-configuration} and then add that location to a web
24015 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
24016 [config=(git-http-configuration)]
24017 Compute an @code{nginx-location-configuration} that corresponds to the
24018 given Git http configuration. An example nginx service definition to
24019 serve the default @file{/srv/git} over HTTPS might be:
24022 (service nginx-service-type
24023 (nginx-configuration
24026 (nginx-server-configuration
24027 (listen '("443 ssl"))
24028 (server-name "git.my-host.org")
24030 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
24031 (ssl-certificate-key
24032 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
24035 (git-http-nginx-location-configuration
24036 (git-http-configuration (uri-path "/"))))))))))
24039 This example assumes that you are using Let's Encrypt to get your TLS
24040 certificate. @xref{Certificate Services}. The default @code{certbot}
24041 service will redirect all HTTP traffic on @code{git.my-host.org} to
24042 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
24043 system services. @xref{Web Services}.
24046 @subsubheading Cgit Service
24048 @cindex Cgit service
24049 @cindex Git, web interface
24050 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
24051 repositories written in C.
24053 The following example will configure the service with default values.
24054 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
24057 (service cgit-service-type)
24060 The @code{file-object} type designates either a file-like object
24061 (@pxref{G-Expressions, file-like objects}) or a string.
24063 @c %start of fragment
24065 Available @code{cgit-configuration} fields are:
24067 @deftypevr {@code{cgit-configuration} parameter} package package
24072 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
24073 NGINX configuration.
24077 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
24078 Specifies a command which will be invoked to format the content of about
24079 pages (both top-level and for each repository).
24081 Defaults to @samp{""}.
24085 @deftypevr {@code{cgit-configuration} parameter} string agefile
24086 Specifies a path, relative to each repository path, which can be used to
24087 specify the date and time of the youngest commit in the repository.
24089 Defaults to @samp{""}.
24093 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
24094 Specifies a command that will be invoked for authenticating repository
24097 Defaults to @samp{""}.
24101 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
24102 Flag which, when set to @samp{age}, enables date ordering in the branch
24103 ref list, and when set @samp{name} enables ordering by branch name.
24105 Defaults to @samp{"name"}.
24109 @deftypevr {@code{cgit-configuration} parameter} string cache-root
24110 Path used to store the cgit cache entries.
24112 Defaults to @samp{"/var/cache/cgit"}.
24116 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
24117 Number which specifies the time-to-live, in minutes, for the cached
24118 version of repository pages accessed with a fixed SHA1.
24120 Defaults to @samp{-1}.
24124 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
24125 Number which specifies the time-to-live, in minutes, for the cached
24126 version of repository pages accessed without a fixed SHA1.
24128 Defaults to @samp{5}.
24132 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
24133 Number which specifies the time-to-live, in minutes, for the cached
24134 version of the repository summary page.
24136 Defaults to @samp{5}.
24140 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
24141 Number which specifies the time-to-live, in minutes, for the cached
24142 version of the repository index page.
24144 Defaults to @samp{5}.
24148 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
24149 Number which specifies the time-to-live, in minutes, for the result of
24150 scanning a path for Git repositories.
24152 Defaults to @samp{15}.
24156 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
24157 Number which specifies the time-to-live, in minutes, for the cached
24158 version of the repository about page.
24160 Defaults to @samp{15}.
24164 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
24165 Number which specifies the time-to-live, in minutes, for the cached
24166 version of snapshots.
24168 Defaults to @samp{5}.
24172 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
24173 The maximum number of entries in the cgit cache. When set to @samp{0},
24174 caching is disabled.
24176 Defaults to @samp{0}.
24180 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
24181 Sort items in the repo list case sensitively.
24183 Defaults to @samp{#t}.
24187 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
24188 List of common prefixes which, when combined with a repository URL,
24189 generates valid clone URLs for the repository.
24191 Defaults to @samp{()}.
24195 @deftypevr {@code{cgit-configuration} parameter} list clone-url
24196 List of @code{clone-url} templates.
24198 Defaults to @samp{()}.
24202 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
24203 Command which will be invoked to format commit messages.
24205 Defaults to @samp{""}.
24209 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
24210 Flag which, when set to @samp{date}, enables strict date ordering in the
24211 commit log, and when set to @samp{topo} enables strict topological
24214 Defaults to @samp{"git log"}.
24218 @deftypevr {@code{cgit-configuration} parameter} file-object css
24219 URL which specifies the css document to include in all cgit pages.
24221 Defaults to @samp{"/share/cgit/cgit.css"}.
24225 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
24226 Specifies a command which will be invoked to format names and email
24227 address of committers, authors, and taggers, as represented in various
24228 places throughout the cgit interface.
24230 Defaults to @samp{""}.
24234 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
24235 Flag which, when set to @samp{#t}, will make cgit generate a HTML
24236 fragment suitable for embedding in other HTML pages.
24238 Defaults to @samp{#f}.
24242 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
24243 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
24244 commit history graph to the left of the commit messages in the
24245 repository log page.
24247 Defaults to @samp{#f}.
24251 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
24252 Flag which, when set to @samp{#t}, allows all filter settings to be
24253 overridden in repository-specific cgitrc files.
24255 Defaults to @samp{#f}.
24259 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
24260 Flag which, when set to @samp{#t}, allows users to follow a file in the
24263 Defaults to @samp{#f}.
24267 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
24268 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
24271 Defaults to @samp{#t}.
24275 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
24276 Flag which, when set to @samp{#t}, will make cgit generate extra links
24277 "summary", "commit", "tree" for each repo in the repository index.
24279 Defaults to @samp{#f}.
24283 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
24284 Flag which, when set to @samp{#t}, will make cgit display the owner of
24285 each repo in the repository index.
24287 Defaults to @samp{#t}.
24291 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
24292 Flag which, when set to @samp{#t}, will make cgit print the number of
24293 modified files for each commit on the repository log page.
24295 Defaults to @samp{#f}.
24299 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
24300 Flag which, when set to @samp{#t}, will make cgit print the number of
24301 added and removed lines for each commit on the repository log page.
24303 Defaults to @samp{#f}.
24307 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
24308 Flag which, when set to @code{#t}, will make cgit display remote
24309 branches in the summary and refs views.
24311 Defaults to @samp{#f}.
24315 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
24316 Flag which, when set to @code{1}, will make cgit use the subject of the
24317 parent commit as link text when generating links to parent commits in
24320 Defaults to @samp{#f}.
24324 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
24325 Flag which, when set to @samp{#t}, will make cgit use the subject of the
24326 parent commit as link text when generating links to parent commits in
24329 Defaults to @samp{#f}.
24333 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
24334 Flag which, when set to @samp{#t}, will make cgit generate linenumber
24335 links for plaintext blobs printed in the tree view.
24337 Defaults to @samp{#t}.
24341 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
24342 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
24343 set any repo specific settings.
24345 Defaults to @samp{#f}.
24349 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
24350 URL used as link to a shortcut icon for cgit.
24352 Defaults to @samp{"/favicon.ico"}.
24356 @deftypevr {@code{cgit-configuration} parameter} string footer
24357 The content of the file specified with this option will be included
24358 verbatim at the bottom of all pages (i.e.@: it replaces the standard
24359 "generated by..."@: message).
24361 Defaults to @samp{""}.
24365 @deftypevr {@code{cgit-configuration} parameter} string head-include
24366 The content of the file specified with this option will be included
24367 verbatim in the HTML HEAD section on all pages.
24369 Defaults to @samp{""}.
24373 @deftypevr {@code{cgit-configuration} parameter} string header
24374 The content of the file specified with this option will be included
24375 verbatim at the top of all pages.
24377 Defaults to @samp{""}.
24381 @deftypevr {@code{cgit-configuration} parameter} file-object include
24382 Name of a configfile to include before the rest of the current config-
24385 Defaults to @samp{""}.
24389 @deftypevr {@code{cgit-configuration} parameter} string index-header
24390 The content of the file specified with this option will be included
24391 verbatim above the repository index.
24393 Defaults to @samp{""}.
24397 @deftypevr {@code{cgit-configuration} parameter} string index-info
24398 The content of the file specified with this option will be included
24399 verbatim below the heading on the repository index page.
24401 Defaults to @samp{""}.
24405 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
24406 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
24407 in the servers timezone.
24409 Defaults to @samp{#f}.
24413 @deftypevr {@code{cgit-configuration} parameter} file-object logo
24414 URL which specifies the source of an image which will be used as a logo
24417 Defaults to @samp{"/share/cgit/cgit.png"}.
24421 @deftypevr {@code{cgit-configuration} parameter} string logo-link
24422 URL loaded when clicking on the cgit logo image.
24424 Defaults to @samp{""}.
24428 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
24429 Command which will be invoked to format the Owner column of the main
24432 Defaults to @samp{""}.
24436 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
24437 Number of items to display in atom feeds view.
24439 Defaults to @samp{10}.
24443 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
24444 Number of entries to list per page in "log" view.
24446 Defaults to @samp{50}.
24450 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
24451 Number of commit message characters to display in "log" view.
24453 Defaults to @samp{80}.
24457 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
24458 Specifies the number of entries to list per page on the repository index
24461 Defaults to @samp{50}.
24465 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
24466 Specifies the maximum number of repo description characters to display
24467 on the repository index page.
24469 Defaults to @samp{80}.
24473 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
24474 Specifies the maximum size of a blob to display HTML for in KBytes.
24476 Defaults to @samp{0}.
24480 @deftypevr {@code{cgit-configuration} parameter} string max-stats
24481 Maximum statistics period. Valid values are @samp{week},@samp{month},
24482 @samp{quarter} and @samp{year}.
24484 Defaults to @samp{""}.
24488 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
24489 Mimetype for the specified filename extension.
24491 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
24492 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
24493 "image/png") (svg "image/svg+xml"))}.
24497 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
24498 Specifies the file to use for automatic mimetype lookup.
24500 Defaults to @samp{""}.
24504 @deftypevr {@code{cgit-configuration} parameter} string module-link
24505 Text which will be used as the formatstring for a hyperlink when a
24506 submodule is printed in a directory listing.
24508 Defaults to @samp{""}.
24512 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
24513 If set to the value @samp{#t} caching will be disabled.
24515 Defaults to @samp{#f}.
24519 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
24520 If set to @samp{#t} showing full author email addresses will be
24523 Defaults to @samp{#f}.
24527 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
24528 Flag which, when set to @samp{#t}, will make cgit omit the standard
24529 header on all pages.
24531 Defaults to @samp{#f}.
24535 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
24536 A list of subdirectories inside of @code{repository-directory}, relative
24537 to it, that should loaded as Git repositories. An empty list means that
24538 all subdirectories will be loaded.
24540 Defaults to @samp{()}.
24544 @deftypevr {@code{cgit-configuration} parameter} file-object readme
24545 Text which will be used as default value for @code{cgit-repo-readme}.
24547 Defaults to @samp{""}.
24551 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
24552 If set to @code{#t} and @code{repository-directory} is enabled, if any
24553 repositories are found with a suffix of @code{.git}, this suffix will be
24554 removed for the URL and name.
24556 Defaults to @samp{#f}.
24560 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
24561 Maximum number of files to consider when detecting renames.
24563 Defaults to @samp{-1}.
24567 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
24568 The way in which repositories in each section are sorted.
24570 Defaults to @samp{""}.
24574 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
24575 Text used as content for the @code{robots} meta-tag.
24577 Defaults to @samp{("noindex" "nofollow")}.
24581 @deftypevr {@code{cgit-configuration} parameter} string root-desc
24582 Text printed below the heading on the repository index page.
24584 Defaults to @samp{"a fast webinterface for the git dscm"}.
24588 @deftypevr {@code{cgit-configuration} parameter} string root-readme
24589 The content of the file specified with this option will be included
24590 verbatim below the "about" link on the repository index page.
24592 Defaults to @samp{""}.
24596 @deftypevr {@code{cgit-configuration} parameter} string root-title
24597 Text printed as heading on the repository index page.
24599 Defaults to @samp{""}.
24603 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
24604 If set to @samp{#t} and repository-directory is enabled,
24605 repository-directory will recurse into directories whose name starts
24606 with a period. Otherwise, repository-directory will stay away from such
24607 directories, considered as "hidden". Note that this does not apply to
24608 the ".git" directory in non-bare repos.
24610 Defaults to @samp{#f}.
24614 @deftypevr {@code{cgit-configuration} parameter} list snapshots
24615 Text which specifies the default set of snapshot formats that cgit
24616 generates links for.
24618 Defaults to @samp{()}.
24622 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
24623 Name of the directory to scan for repositories (represents
24626 Defaults to @samp{"/srv/git"}.
24630 @deftypevr {@code{cgit-configuration} parameter} string section
24631 The name of the current repository section - all repositories defined
24632 after this option will inherit the current section name.
24634 Defaults to @samp{""}.
24638 @deftypevr {@code{cgit-configuration} parameter} string section-sort
24639 Flag which, when set to @samp{1}, will sort the sections on the
24640 repository listing by name.
24642 Defaults to @samp{""}.
24646 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
24647 A number which, if defined prior to repository-directory, specifies how
24648 many path elements from each repo path to use as a default section name.
24650 Defaults to @samp{0}.
24654 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
24655 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
24658 Defaults to @samp{#f}.
24662 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
24663 Specifies a command which will be invoked to format plaintext blobs in
24666 Defaults to @samp{""}.
24670 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
24671 Specifies the number of branches to display in the repository "summary"
24674 Defaults to @samp{10}.
24678 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
24679 Specifies the number of log entries to display in the repository
24682 Defaults to @samp{10}.
24686 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
24687 Specifies the number of tags to display in the repository "summary"
24690 Defaults to @samp{10}.
24694 @deftypevr {@code{cgit-configuration} parameter} string strict-export
24695 Filename which, if specified, needs to be present within the repository
24696 for cgit to allow access to that repository.
24698 Defaults to @samp{""}.
24702 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
24703 URL which, if specified, will be used as root for all cgit links.
24705 Defaults to @samp{"/"}.
24709 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
24710 A list of @dfn{cgit-repo} records to use with config.
24712 Defaults to @samp{()}.
24714 Available @code{repository-cgit-configuration} fields are:
24716 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
24717 A mask of snapshot formats for this repo that cgit generates links for,
24718 restricted by the global @code{snapshots} setting.
24720 Defaults to @samp{()}.
24724 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
24725 Override the default @code{source-filter}.
24727 Defaults to @samp{""}.
24731 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
24732 The relative URL used to access the repository.
24734 Defaults to @samp{""}.
24738 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
24739 Override the default @code{about-filter}.
24741 Defaults to @samp{""}.
24745 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
24746 Flag which, when set to @samp{age}, enables date ordering in the branch
24747 ref list, and when set to @samp{name} enables ordering by branch name.
24749 Defaults to @samp{""}.
24753 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
24754 A list of URLs which can be used to clone repo.
24756 Defaults to @samp{()}.
24760 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
24761 Override the default @code{commit-filter}.
24763 Defaults to @samp{""}.
24767 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
24768 Flag which, when set to @samp{date}, enables strict date ordering in the
24769 commit log, and when set to @samp{topo} enables strict topological
24772 Defaults to @samp{""}.
24776 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
24777 The name of the default branch for this repository. If no such branch
24778 exists in the repository, the first branch name (when sorted) is used as
24779 default instead. By default branch pointed to by HEAD, or "master" if
24780 there is no suitable HEAD.
24782 Defaults to @samp{""}.
24786 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
24787 The value to show as repository description.
24789 Defaults to @samp{""}.
24793 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
24794 The value to show as repository homepage.
24796 Defaults to @samp{""}.
24800 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
24801 Override the default @code{email-filter}.
24803 Defaults to @samp{""}.
24807 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
24808 A flag which can be used to disable the global setting
24809 @code{enable-commit-graph?}.
24811 Defaults to @samp{disabled}.
24815 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
24816 A flag which can be used to disable the global setting
24817 @code{enable-log-filecount?}.
24819 Defaults to @samp{disabled}.
24823 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
24824 A flag which can be used to disable the global setting
24825 @code{enable-log-linecount?}.
24827 Defaults to @samp{disabled}.
24831 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
24832 Flag which, when set to @code{#t}, will make cgit display remote
24833 branches in the summary and refs views.
24835 Defaults to @samp{disabled}.
24839 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
24840 A flag which can be used to override the global setting
24841 @code{enable-subject-links?}.
24843 Defaults to @samp{disabled}.
24847 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
24848 A flag which can be used to override the global setting
24849 @code{enable-html-serving?}.
24851 Defaults to @samp{disabled}.
24855 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
24856 Flag which, when set to @code{#t}, hides the repository from the
24859 Defaults to @samp{#f}.
24863 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
24864 Flag which, when set to @samp{#t}, ignores the repository.
24866 Defaults to @samp{#f}.
24870 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
24871 URL which specifies the source of an image which will be used as a logo
24872 on this repo’s pages.
24874 Defaults to @samp{""}.
24878 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
24879 URL loaded when clicking on the cgit logo image.
24881 Defaults to @samp{""}.
24885 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
24886 Override the default @code{owner-filter}.
24888 Defaults to @samp{""}.
24892 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
24893 Text which will be used as the formatstring for a hyperlink when a
24894 submodule is printed in a directory listing. The arguments for the
24895 formatstring are the path and SHA1 of the submodule commit.
24897 Defaults to @samp{""}.
24901 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
24902 Text which will be used as the formatstring for a hyperlink when a
24903 submodule with the specified subdirectory path is printed in a directory
24906 Defaults to @samp{()}.
24910 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
24911 Override the default maximum statistics period.
24913 Defaults to @samp{""}.
24917 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
24918 The value to show as repository name.
24920 Defaults to @samp{""}.
24924 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
24925 A value used to identify the owner of the repository.
24927 Defaults to @samp{""}.
24931 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
24932 An absolute path to the repository directory.
24934 Defaults to @samp{""}.
24938 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
24939 A path (relative to repo) which specifies a file to include verbatim as
24940 the "About" page for this repo.
24942 Defaults to @samp{""}.
24946 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
24947 The name of the current repository section - all repositories defined
24948 after this option will inherit the current section name.
24950 Defaults to @samp{""}.
24954 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
24955 Extra options will be appended to cgitrc file.
24957 Defaults to @samp{()}.
24963 @deftypevr {@code{cgit-configuration} parameter} list extra-options
24964 Extra options will be appended to cgitrc file.
24966 Defaults to @samp{()}.
24971 @c %end of fragment
24973 However, it could be that you just want to get a @code{cgitrc} up and
24974 running. In that case, you can pass an @code{opaque-cgit-configuration}
24975 as a record to @code{cgit-service-type}. As its name indicates, an
24976 opaque configuration does not have easy reflective capabilities.
24978 Available @code{opaque-cgit-configuration} fields are:
24980 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
24984 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
24985 The contents of the @code{cgitrc}, as a string.
24988 For example, if your @code{cgitrc} is just the empty string, you
24989 could instantiate a cgit service like this:
24992 (service cgit-service-type
24993 (opaque-cgit-configuration
24997 @subsubheading Gitolite Service
24999 @cindex Gitolite service
25000 @cindex Git, hosting
25001 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
25002 repositories on a central server.
25004 Gitolite can handle multiple repositories and users, and supports flexible
25005 configuration of the permissions for the users on the repositories.
25007 The following example will configure Gitolite using the default @code{git}
25008 user, and the provided SSH public key.
25011 (service gitolite-service-type
25012 (gitolite-configuration
25013 (admin-pubkey (plain-file
25015 "ssh-rsa AAAA... guix@@example.com"))))
25018 Gitolite is configured through a special admin repository which you can clone,
25019 for example, if you setup Gitolite on @code{example.com}, you would run the
25020 following command to clone the admin repository.
25023 git clone git@@example.com:gitolite-admin
25026 When the Gitolite service is activated, the provided @code{admin-pubkey} will
25027 be inserted in to the @file{keydir} directory in the gitolite-admin
25028 repository. If this results in a change in the repository, it will be
25029 committed using the message ``gitolite setup by GNU Guix''.
25031 @deftp {Data Type} gitolite-configuration
25032 Data type representing the configuration for @code{gitolite-service-type}.
25035 @item @code{package} (default: @var{gitolite})
25036 Gitolite package to use.
25038 @item @code{user} (default: @var{git})
25039 User to use for Gitolite. This will be user that you use when accessing
25042 @item @code{group} (default: @var{git})
25043 Group to use for Gitolite.
25045 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
25046 Directory in which to store the Gitolite configuration and repositories.
25048 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
25049 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
25050 representing the configuration for Gitolite.
25052 @item @code{admin-pubkey} (default: @var{#f})
25053 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
25054 setup Gitolite. This will be inserted in to the @file{keydir} directory
25055 within the gitolite-admin repository.
25057 To specify the SSH key as a string, use the @code{plain-file} function.
25060 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
25066 @deftp {Data Type} gitolite-rc-file
25067 Data type representing the Gitolite RC file.
25070 @item @code{umask} (default: @code{#o0077})
25071 This controls the permissions Gitolite sets on the repositories and their
25074 A value like @code{#o0027} will give read access to the group used by Gitolite
25075 (by default: @code{git}). This is necessary when using Gitolite with software
25076 like cgit or gitweb.
25078 @item @code{git-config-keys} (default: @code{""})
25079 Gitolite allows you to set git config values using the "config" keyword. This
25080 setting allows control over the config keys to accept.
25082 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
25083 Set the role names allowed to be used by users running the perms command.
25085 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
25086 This setting controls the commands and features to enable within Gitolite.
25092 @node Game Services
25093 @subsection Game Services
25095 @subsubheading The Battle for Wesnoth Service
25097 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
25098 based tactical strategy game, with several single player campaigns, and
25099 multiplayer games (both networked and local).
25101 @defvar {Scheme Variable} wesnothd-service-type
25102 Service type for the wesnothd service. Its value must be a
25103 @code{wesnothd-configuration} object. To run wesnothd in the default
25104 configuration, instantiate it as:
25107 (service wesnothd-service-type)
25111 @deftp {Data Type} wesnothd-configuration
25112 Data type representing the configuration of @command{wesnothd}.
25115 @item @code{package} (default: @code{wesnoth-server})
25116 The wesnoth server package to use.
25118 @item @code{port} (default: @code{15000})
25119 The port to bind the server to.
25124 @node PAM Mount Service
25125 @subsection PAM Mount Service
25128 The @code{(gnu services pam-mount)} module provides a service allowing
25129 users to mount volumes when they log in. It should be able to mount any
25130 volume format supported by the system.
25132 @defvar {Scheme Variable} pam-mount-service-type
25133 Service type for PAM Mount support.
25136 @deftp {Data Type} pam-mount-configuration
25137 Data type representing the configuration of PAM Mount.
25139 It takes the following parameters:
25143 The configuration rules that will be used to generate
25144 @file{/etc/security/pam_mount.conf.xml}.
25146 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
25147 Guile Reference Manual}), and the the default ones don't mount anything
25148 for anyone at login:
25151 `((debug (@@ (enable "0")))
25152 (mntoptions (@@ (allow ,(string-join
25153 '("nosuid" "nodev" "loop"
25154 "encryption" "fsck" "nonempty"
25155 "allow_root" "allow_other")
25157 (mntoptions (@@ (require "nosuid,nodev")))
25158 (logout (@@ (wait "0")
25162 (mkmountpoint (@@ (enable "1")
25166 Some @code{volume} elements must be added to automatically mount volumes
25167 at login. Here's an example allowing the user @code{alice} to mount her
25168 encrypted @code{HOME} directory and allowing the user @code{bob} to mount
25169 the partition where he stores his data:
25172 (define pam-mount-rules
25173 `((debug (@@ (enable "0")))
25174 (volume (@@ (user "alice")
25177 (mountpoint "/home/alice")))
25178 (volume (@@ (user "bob")
25181 (mountpoint "/home/bob/data")
25182 (options "defaults,autodefrag,compress")))
25183 (mntoptions (@@ (allow ,(string-join
25184 '("nosuid" "nodev" "loop"
25185 "encryption" "fsck" "nonempty"
25186 "allow_root" "allow_other")
25188 (mntoptions (@@ (require "nosuid,nodev")))
25189 (logout (@@ (wait "0")
25193 (mkmountpoint (@@ (enable "1")
25194 (remove "true")))))
25196 (service pam-mount-service-type
25197 (pam-mount-configuration
25198 (rules pam-mount-rules)))
25201 The complete list of possible options can be found in the man page for
25202 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
25207 @node Guix Services
25208 @subsection Guix Services
25210 @subsubheading Guix Data Service
25211 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
25212 and provides data about GNU Guix. This includes information about
25213 packages, derivations and lint warnings.
25215 The data is stored in a PostgreSQL database, and available through a web
25218 @defvar {Scheme Variable} guix-data-service-type
25219 Service type for the Guix Data Service. Its value must be a
25220 @code{guix-data-service-configuration} object. The service optionally
25221 extends the getmail service, as the guix-commits mailing list is used to
25222 find out about changes in the Guix git repository.
25225 @deftp {Data Type} guix-data-service-configuration
25226 Data type representing the configuration of the Guix Data Service.
25229 @item @code{package} (default: @code{guix-data-service})
25230 The Guix Data Service package to use.
25232 @item @code{user} (default: @code{"guix-data-service"})
25233 The system user to run the service as.
25235 @item @code{group} (default: @code{"guix-data-service"})
25236 The system group to run the service as.
25238 @item @code{port} (default: @code{8765})
25239 The port to bind the web service to.
25241 @item @code{host} (default: @code{"127.0.0.1"})
25242 The host to bind the web service to.
25244 @item @code{getmail-idle-mailboxes} (default: @code{#f})
25245 If set, this is the list of mailboxes that the getmail service will be
25246 configured to listen to.
25248 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
25249 If set, this is the @code{getmail-retriever-configuration} object with
25250 which to configure getmail to fetch mail from the guix-commits mailing
25253 @item @code{extra-options} (default: @var{'()})
25254 Extra command line options for @code{guix-data-service}.
25256 @item @code{extra-process-jobs-options} (default: @var{'()})
25257 Extra command line options for @code{guix-data-service-process-jobs}.
25262 @node Linux Services
25263 @subsubheading Linux Services
25266 @cindex out of memory killer
25268 @cindex early out of memory daemon
25269 @subsection Early OOM Service
25271 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
25272 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
25273 space and provides a more responsive and configurable alternative to the
25274 in-kernel OOM killer. It is useful to prevent the system from becoming
25275 unresponsive when it runs out of memory.
25277 @deffn {Scheme Variable} earlyoom-service-type
25278 The service type for running @command{earlyoom}, the Early OOM daemon.
25279 Its value must be a @code{earlyoom-configuration} object, described
25280 below. The service can be instantiated in its default configuration
25284 (service earlyoom-service-type)
25288 @deftp {Data Type} earlyoom-configuration
25289 This is the configuration record for the @code{earlyoom-service-type}.
25292 @item @code{earlyoom} (default: @var{earlyoom})
25293 The Earlyoom package to use.
25295 @item @code{minimum-available-memory} (default: @code{10})
25296 The threshold for the minimum @emph{available} memory, in percentages.
25298 @item @code{minimum-free-swap} (default: @code{10})
25299 The threshold for the minimum free swap memory, in percentages.
25301 @item @code{prefer-regexp} (default: @code{#f})
25302 A regular expression (as a string) to match the names of the processes
25303 that should be preferably killed.
25305 @item @code{avoid-regexp} (default: @code{#f})
25306 A regular expression (as a string) to match the names of the processes
25307 that should @emph{not} be killed.
25309 @item @code{memory-report-interval} (default: @code{0})
25310 The interval in seconds at which a memory report is printed. It is
25311 disabled by default.
25313 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
25314 A boolean indicating whether the positive adjustments set in
25315 @file{/proc/*/oom_score_adj}.
25317 @item @code{show-debug-messages?} (default: @code{#f})
25318 A boolean indicating whether debug messages should be printed. The logs
25319 are saved at @file{/var/log/earlyoom.log}.
25321 @item @code{send-notification-command} (default: @code{#f})
25322 This can be used to provide a custom command used for sending
25328 @node Miscellaneous Services
25329 @subsection Miscellaneous Services
25331 @cindex fingerprint
25332 @subsubheading Fingerprint Service
25334 The @code{(gnu services authentication)} module provides a DBus service to
25335 read and identify fingerprints via a fingerprint sensor.
25337 @defvr {Scheme Variable} fprintd-service-type
25338 The service type for @command{fprintd}, which provides the fingerprint
25339 reading capability.
25342 (service fprintd-service-type)
25347 @subsubheading System Control Service
25349 The @code{(gnu services sysctl)} provides a service to configure kernel
25350 parameters at boot.
25352 @defvr {Scheme Variable} sysctl-service-type
25353 The service type for @command{sysctl}, which modifies kernel parameters
25354 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
25358 (service sysctl-service-type
25359 (sysctl-configuration
25360 (settings '(("net.ipv4.ip_forward" . "1")))))
25364 @deftp {Data Type} sysctl-configuration
25365 The data type representing the configuration of @command{sysctl}.
25368 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
25369 The @command{sysctl} executable to use.
25371 @item @code{settings} (default: @code{'()})
25372 An association list specifies kernel parameters and their values.
25377 @subsubheading PC/SC Smart Card Daemon Service
25379 The @code{(gnu services security-token)} module provides the following service
25380 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
25381 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
25382 manager that coordinates communications with smart card readers, smart cards
25383 and cryptographic tokens that are connected to the system.
25385 @defvr {Scheme Variable} pcscd-service-type
25386 Service type for the @command{pcscd} service. Its value must be a
25387 @code{pcscd-configuration} object. To run pcscd in the default
25388 configuration, instantiate it as:
25391 (service pcscd-service-type)
25395 @deftp {Data Type} pcscd-configuration
25396 The data type representing the configuration of @command{pcscd}.
25399 @item @code{pcsc-lite} (default: @code{pcsc-lite})
25400 The pcsc-lite package that provides pcscd.
25401 @item @code{usb-drivers} (default: @code{(list ccid)})
25402 List of packages that provide USB drivers to pcscd. Drivers are expected to be
25403 under @file{pcsc/drivers} in the store directory of the package.
25408 @subsubheading Lirc Service
25410 The @code{(gnu services lirc)} module provides the following service.
25412 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
25413 [#:device #f] [#:driver #f] [#:config-file #f] @
25414 [#:extra-options '()]
25415 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
25416 decodes infrared signals from remote controls.
25418 Optionally, @var{device}, @var{driver} and @var{config-file}
25419 (configuration file name) may be specified. See @command{lircd} manual
25422 Finally, @var{extra-options} is a list of additional command-line options
25423 passed to @command{lircd}.
25427 @subsubheading Spice Service
25429 The @code{(gnu services spice)} module provides the following service.
25431 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
25432 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
25433 that enables sharing the clipboard with a vm and setting the guest display
25434 resolution when the graphical console window resizes.
25437 @cindex inputattach
25438 @subsubheading inputattach Service
25440 @cindex tablet input, for Xorg
25441 @cindex touchscreen input, for Xorg
25442 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
25443 use input devices such as Wacom tablets, touchscreens, or joysticks with the
25444 Xorg display server.
25446 @deffn {Scheme Variable} inputattach-service-type
25447 Type of a service that runs @command{inputattach} on a device and
25448 dispatches events from it.
25451 @deftp {Data Type} inputattach-configuration
25453 @item @code{device-type} (default: @code{"wacom"})
25454 The type of device to connect to. Run @command{inputattach --help}, from the
25455 @code{inputattach} package, to see the list of supported device types.
25457 @item @code{device} (default: @code{"/dev/ttyS0"})
25458 The device file to connect to the device.
25460 @item @code{baud-rate} (default: @code{#f})
25461 Baud rate to use for the serial connection.
25462 Should be a number or @code{#f}.
25464 @item @code{log-file} (default: @code{#f})
25465 If true, this must be the name of a file to log messages to.
25469 @subsection Dictionary Services
25471 The @code{(gnu services dict)} module provides the following service:
25473 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
25474 Return a service that runs the @command{dicod} daemon, an implementation
25475 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
25477 The optional @var{config} argument specifies the configuration for
25478 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
25479 default it serves the GNU Collaborative International Dictionary of English.
25481 You can add @command{open localhost} to your @file{~/.dico} file to make
25482 @code{localhost} the default server for @command{dico} client
25483 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
25486 @deftp {Data Type} dicod-configuration
25487 Data type representing the configuration of dicod.
25490 @item @code{dico} (default: @var{dico})
25491 Package object of the GNU Dico dictionary server.
25493 @item @code{interfaces} (default: @var{'("localhost")})
25494 This is the list of IP addresses and ports and possibly socket file
25495 names to listen to (@pxref{Server Settings, @code{listen} directive,,
25496 dico, GNU Dico Manual}).
25498 @item @code{handlers} (default: @var{'()})
25499 List of @code{<dicod-handler>} objects denoting handlers (module instances).
25501 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
25502 List of @code{<dicod-database>} objects denoting dictionaries to be served.
25506 @deftp {Data Type} dicod-handler
25507 Data type representing a dictionary handler (module instance).
25511 Name of the handler (module instance).
25513 @item @code{module} (default: @var{#f})
25514 Name of the dicod module of the handler (instance). If it is @code{#f},
25515 the module has the same name as the handler.
25516 (@pxref{Modules,,, dico, GNU Dico Manual}).
25518 @item @code{options}
25519 List of strings or gexps representing the arguments for the module handler
25523 @deftp {Data Type} dicod-database
25524 Data type representing a dictionary database.
25528 Name of the database, will be used in DICT commands.
25530 @item @code{handler}
25531 Name of the dicod handler (module instance) used by this database
25532 (@pxref{Handlers,,, dico, GNU Dico Manual}).
25534 @item @code{complex?} (default: @var{#f})
25535 Whether the database configuration complex. The complex configuration
25536 will need a corresponding @code{<dicod-handler>} object, otherwise not.
25538 @item @code{options}
25539 List of strings or gexps representing the arguments for the database
25540 (@pxref{Databases,,, dico, GNU Dico Manual}).
25544 @defvr {Scheme Variable} %dicod-database:gcide
25545 A @code{<dicod-database>} object serving the GNU Collaborative International
25546 Dictionary of English using the @code{gcide} package.
25549 The following is an example @code{dicod-service} configuration.
25552 (dicod-service #:config
25553 (dicod-configuration
25554 (handlers (list (dicod-handler
25558 (list #~(string-append "dbdir=" #$wordnet))))))
25559 (databases (list (dicod-database
25562 (handler "wordnet")
25563 (options '("database=wn")))
25564 %dicod-database:gcide))))
25568 @subsubheading Docker Service
25570 The @code{(gnu services docker)} module provides the following services.
25572 @defvr {Scheme Variable} docker-service-type
25574 This is the type of the service that runs @url{https://www.docker.com,Docker},
25575 a daemon that can execute application bundles (sometimes referred to as
25576 ``containers'') in isolated environments.
25580 @deftp {Data Type} docker-configuration
25581 This is the data type representing the configuration of Docker and Containerd.
25585 @item @code{package} (default: @code{docker})
25586 The Docker package to use.
25588 @item @code{containerd} (default: @var{containerd})
25589 The Containerd package to use.
25595 @subsubheading Auditd Service
25597 The @code{(gnu services auditd)} module provides the following service.
25599 @defvr {Scheme Variable} auditd-service-type
25601 This is the type of the service that runs
25602 @url{https://people.redhat.com/sgrubb/audit/,auditd},
25603 a daemon that tracks security-relevant information on your system.
25605 Examples of things that can be tracked:
25615 Failed login attempts
25622 @command{auditctl} from the @code{audit} package can be used in order
25623 to add or remove events to be tracked (until the next reboot).
25624 In order to permanently track events, put the command line arguments
25625 of auditctl into @file{/etc/audit/audit.rules}.
25626 @command{aureport} from the @code{audit} package can be used in order
25627 to view a report of all recorded events.
25628 The audit daemon usually logs into the directory @file{/var/log/audit}.
25632 @deftp {Data Type} auditd-configuration
25633 This is the data type representing the configuration of auditd.
25637 @item @code{audit} (default: @code{audit})
25638 The audit package to use.
25643 @defvr {Scheme Variable} singularity-service-type
25644 This is the type of the service that allows you to run
25645 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
25646 create and run application bundles (aka. ``containers''). The value for this
25647 service is the Singularity package to use.
25649 The service does not install a daemon; instead, it installs helper programs as
25650 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
25651 @command{singularity run} and similar commands.
25655 @subsubheading Nix service
25657 The @code{(gnu services nix)} module provides the following service.
25659 @defvr {Scheme Variable} nix-service-type
25661 This is the type of the service that runs build daemon of the
25662 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
25666 (use-modules (gnu))
25667 (use-service-modules nix)
25668 (use-package-modules package-management)
25672 (packages (append (list nix)
25675 (services (append (list (service nix-service-type))
25679 After @command{guix system reconfigure} configure Nix for your user:
25682 @item Add a Nix channel and update it. See
25683 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
25685 @item Create a symlink to your profile and activate Nix profile:
25689 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
25690 $ source /run/current-system/profile/etc/profile.d/nix.sh
25695 @node Setuid Programs
25696 @section Setuid Programs
25698 @cindex setuid programs
25699 Some programs need to run with ``root'' privileges, even when they are
25700 launched by unprivileged users. A notorious example is the
25701 @command{passwd} program, which users can run to change their
25702 password, and which needs to access the @file{/etc/passwd} and
25703 @file{/etc/shadow} files---something normally restricted to root, for
25704 obvious security reasons. To address that, these executables are
25705 @dfn{setuid-root}, meaning that they always run with root privileges
25706 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
25707 for more info about the setuid mechanism.)
25709 The store itself @emph{cannot} contain setuid programs: that would be a
25710 security issue since any user on the system can write derivations that
25711 populate the store (@pxref{The Store}). Thus, a different mechanism is
25712 used: instead of changing the setuid bit directly on files that are in
25713 the store, we let the system administrator @emph{declare} which programs
25714 should be setuid root.
25716 The @code{setuid-programs} field of an @code{operating-system}
25717 declaration contains a list of G-expressions denoting the names of
25718 programs to be setuid-root (@pxref{Using the Configuration System}).
25719 For instance, the @command{passwd} program, which is part of the Shadow
25720 package, can be designated by this G-expression (@pxref{G-Expressions}):
25723 #~(string-append #$shadow "/bin/passwd")
25726 A default set of setuid programs is defined by the
25727 @code{%setuid-programs} variable of the @code{(gnu system)} module.
25729 @defvr {Scheme Variable} %setuid-programs
25730 A list of G-expressions denoting common programs that are setuid-root.
25732 The list includes commands such as @command{passwd}, @command{ping},
25733 @command{su}, and @command{sudo}.
25736 Under the hood, the actual setuid programs are created in the
25737 @file{/run/setuid-programs} directory at system activation time. The
25738 files in this directory refer to the ``real'' binaries, which are in the
25741 @node X.509 Certificates
25742 @section X.509 Certificates
25744 @cindex HTTPS, certificates
25745 @cindex X.509 certificates
25747 Web servers available over HTTPS (that is, HTTP over the transport-layer
25748 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
25749 that the client can then use to @emph{authenticate} the server. To do
25750 that, clients verify that the server's certificate is signed by a
25751 so-called @dfn{certificate authority} (CA). But to verify the CA's
25752 signature, clients must have first acquired the CA's certificate.
25754 Web browsers such as GNU@tie{}IceCat include their own set of CA
25755 certificates, such that they are able to verify CA signatures
25758 However, most other programs that can talk HTTPS---@command{wget},
25759 @command{git}, @command{w3m}, etc.---need to be told where CA
25760 certificates can be found.
25762 @cindex @code{nss-certs}
25763 In Guix, this is done by adding a package that provides certificates
25764 to the @code{packages} field of the @code{operating-system} declaration
25765 (@pxref{operating-system Reference}). Guix includes one such package,
25766 @code{nss-certs}, which is a set of CA certificates provided as part of
25767 Mozilla's Network Security Services.
25769 Note that it is @emph{not} part of @code{%base-packages}, so you need to
25770 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
25771 most applications and libraries look for certificates by default, points
25772 to the certificates installed globally.
25774 Unprivileged users, including users of Guix on a foreign distro,
25775 can also install their own certificate package in
25776 their profile. A number of environment variables need to be defined so
25777 that applications and libraries know where to find them. Namely, the
25778 OpenSSL library honors the @code{SSL_CERT_DIR} and @code{SSL_CERT_FILE}
25779 variables. Some applications add their own environment variables; for
25780 instance, the Git version control system honors the certificate bundle
25781 pointed to by the @code{GIT_SSL_CAINFO} environment variable. Thus, you
25782 would typically run something like:
25785 $ guix install nss-certs
25786 $ export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
25787 $ export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
25788 $ export GIT_SSL_CAINFO="$SSL_CERT_FILE"
25791 As another example, R requires the @code{CURL_CA_BUNDLE} environment
25792 variable to point to a certificate bundle, so you would have to run
25793 something like this:
25796 $ guix install nss-certs
25797 $ export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
25800 For other applications you may want to look up the required environment
25801 variable in the relevant documentation.
25804 @node Name Service Switch
25805 @section Name Service Switch
25807 @cindex name service switch
25809 The @code{(gnu system nss)} module provides bindings to the
25810 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
25811 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
25812 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
25813 extended with new ``name'' lookup methods for system databases, which
25814 includes host names, service names, user accounts, and more (@pxref{Name
25815 Service Switch, System Databases and Name Service Switch,, libc, The GNU
25816 C Library Reference Manual}).
25818 The NSS configuration specifies, for each system database, which lookup
25819 method is to be used, and how the various methods are chained
25820 together---for instance, under which circumstances NSS should try the
25821 next method in the list. The NSS configuration is given in the
25822 @code{name-service-switch} field of @code{operating-system} declarations
25823 (@pxref{operating-system Reference, @code{name-service-switch}}).
25826 @cindex .local, host name lookup
25827 As an example, the declaration below configures the NSS to use the
25828 @uref{http://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
25829 back-end}, which supports host name lookups over multicast DNS (mDNS)
25830 for host names ending in @code{.local}:
25833 (name-service-switch
25834 (hosts (list %files ;first, check /etc/hosts
25836 ;; If the above did not succeed, try
25837 ;; with 'mdns_minimal'.
25839 (name "mdns_minimal")
25841 ;; 'mdns_minimal' is authoritative for
25842 ;; '.local'. When it returns "not found",
25843 ;; no need to try the next methods.
25844 (reaction (lookup-specification
25845 (not-found => return))))
25847 ;; Then fall back to DNS.
25851 ;; Finally, try with the "full" 'mdns'.
25856 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
25857 contains this configuration, so you will not have to type it if all you
25858 want is to have @code{.local} host lookup working.
25860 Note that, in this case, in addition to setting the
25861 @code{name-service-switch} of the @code{operating-system} declaration,
25862 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
25863 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
25864 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
25865 to the name service cache daemon (@pxref{Base Services,
25866 @code{nscd-service}}).
25868 For convenience, the following variables provide typical NSS
25871 @defvr {Scheme Variable} %default-nss
25872 This is the default name service switch configuration, a
25873 @code{name-service-switch} object.
25876 @defvr {Scheme Variable} %mdns-host-lookup-nss
25877 This is the name service switch configuration with support for host name
25878 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
25881 The reference for name service switch configuration is given below. It
25882 is a direct mapping of the configuration file format of the C library , so
25883 please refer to the C library manual for more information (@pxref{NSS
25884 Configuration File,,, libc, The GNU C Library Reference Manual}).
25885 Compared to the configuration file format of libc NSS, it has the advantage
25886 not only of adding this warm parenthetic feel that we like, but also
25887 static checks: you will know about syntax errors and typos as soon as you
25888 run @command{guix system}.
25890 @deftp {Data Type} name-service-switch
25892 This is the data type representation the configuration of libc's name
25893 service switch (NSS). Each field below represents one of the supported
25910 The system databases handled by the NSS. Each of these fields must be a
25911 list of @code{<name-service>} objects (see below).
25915 @deftp {Data Type} name-service
25917 This is the data type representing an actual name service and the
25918 associated lookup action.
25922 A string denoting the name service (@pxref{Services in the NSS
25923 configuration,,, libc, The GNU C Library Reference Manual}).
25925 Note that name services listed here must be visible to nscd. This is
25926 achieved by passing the @code{#:name-services} argument to
25927 @code{nscd-service} the list of packages providing the needed name
25928 services (@pxref{Base Services, @code{nscd-service}}).
25931 An action specified using the @code{lookup-specification} macro
25932 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
25933 Reference Manual}). For example:
25936 (lookup-specification (unavailable => continue)
25937 (success => return))
25942 @node Initial RAM Disk
25943 @section Initial RAM Disk
25946 @cindex initial RAM disk
25947 For bootstrapping purposes, the Linux-Libre kernel is passed an
25948 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
25949 root file system as well as an initialization script. The latter is
25950 responsible for mounting the real root file system, and for loading any
25951 kernel modules that may be needed to achieve that.
25953 The @code{initrd-modules} field of an @code{operating-system}
25954 declaration allows you to specify Linux-libre kernel modules that must
25955 be available in the initrd. In particular, this is where you would list
25956 modules needed to actually drive the hard disk where your root partition
25957 is---although the default value of @code{initrd-modules} should cover
25958 most use cases. For example, assuming you need the @code{megaraid_sas}
25959 module in addition to the default modules to be able to access your root
25960 file system, you would write:
25965 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
25968 @defvr {Scheme Variable} %base-initrd-modules
25969 This is the list of kernel modules included in the initrd by default.
25972 Furthermore, if you need lower-level customization, the @code{initrd}
25973 field of an @code{operating-system} declaration allows
25974 you to specify which initrd you would like to use. The @code{(gnu
25975 system linux-initrd)} module provides three ways to build an initrd: the
25976 high-level @code{base-initrd} procedure and the low-level
25977 @code{raw-initrd} and @code{expression->initrd} procedures.
25979 The @code{base-initrd} procedure is intended to cover most common uses.
25980 For example, if you want to add a bunch of kernel modules to be loaded
25981 at boot time, you can define the @code{initrd} field of the operating
25982 system declaration like this:
25985 (initrd (lambda (file-systems . rest)
25986 ;; Create a standard initrd but set up networking
25987 ;; with the parameters QEMU expects by default.
25988 (apply base-initrd file-systems
25989 #:qemu-networking? #t
25993 The @code{base-initrd} procedure also handles common use cases that
25994 involves using the system as a QEMU guest, or as a ``live'' system with
25995 volatile root file system.
25997 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
25998 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
25999 such as trying to guess which kernel modules and packages should be included
26000 to the initrd. An example use of @code{raw-initrd} is when a user has
26001 a custom Linux kernel configuration and default kernel modules included by
26002 @code{base-initrd} are not available.
26004 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
26005 honors several options passed on the Linux kernel command line
26006 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
26007 @code{-append} option of QEMU), notably:
26010 @item --load=@var{boot}
26011 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
26012 program, once it has mounted the root file system.
26014 Guix uses this option to yield control to a boot program that runs the
26015 service activation programs and then spawns the GNU@tie{}Shepherd, the
26016 initialization system.
26018 @item --root=@var{root}
26019 Mount @var{root} as the root file system. @var{root} can be a
26020 device name like @code{/dev/sda1}, a file system label, or a file system
26023 @item --system=@var{system}
26024 Have @file{/run/booted-system} and @file{/run/current-system} point to
26027 @item modprobe.blacklist=@var{modules}@dots{}
26028 @cindex module, black-listing
26029 @cindex black list, of kernel modules
26030 Instruct the initial RAM disk as well as the @command{modprobe} command
26031 (from the kmod package) to refuse to load @var{modules}. @var{modules}
26032 must be a comma-separated list of module names---e.g.,
26033 @code{usbkbd,9pnet}.
26036 Start a read-eval-print loop (REPL) from the initial RAM disk before it
26037 tries to load kernel modules and to mount the root file system. Our
26038 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
26039 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
26040 Manual}, for more information on Guile's REPL.
26044 Now that you know all the features that initial RAM disks produced by
26045 @code{base-initrd} and @code{raw-initrd} provide,
26046 here is how to use it and customize it further.
26049 @cindex initial RAM disk
26050 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
26051 [#:linux-modules '()] [#:mapped-devices '()] @
26052 [#:keyboard-layout #f] @
26053 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
26054 Return a derivation that builds a raw initrd. @var{file-systems} is
26055 a list of file systems to be mounted by the initrd, possibly in addition to
26056 the root file system specified on the kernel command line via @code{--root}.
26057 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
26058 @var{mapped-devices} is a list of device mappings to realize before
26059 @var{file-systems} are mounted (@pxref{Mapped Devices}).
26060 @var{helper-packages} is a list of packages to be copied in the initrd. It may
26061 include @code{e2fsck/static} or other packages needed by the initrd to check
26062 the root file system.
26064 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26065 the desired console keyboard layout. This is done before @var{mapped-devices}
26066 are set up and before @var{file-systems} are mounted such that, should the
26067 user need to enter a passphrase or use the REPL, this happens using the
26068 intended keyboard layout.
26070 When @var{qemu-networking?} is true, set up networking with the standard QEMU
26071 parameters. When @var{virtio?} is true, load additional modules so that the
26072 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
26074 When @var{volatile-root?} is true, the root file system is writable but any changes
26078 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
26079 [#:mapped-devices '()] [#:keyboard-layout #f] @
26080 [#:qemu-networking? #f] [#:volatile-root? #f] @
26081 [#:linux-modules '()]
26082 Return as a file-like object a generic initrd, with kernel
26083 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
26084 mounted by the initrd, possibly in addition to the root file system specified
26085 on the kernel command line via @code{--root}. @var{mapped-devices} is a list of device
26086 mappings to realize before @var{file-systems} are mounted.
26088 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
26089 the desired console keyboard layout. This is done before @var{mapped-devices}
26090 are set up and before @var{file-systems} are mounted such that, should the
26091 user need to enter a passphrase or use the REPL, this happens using the
26092 intended keyboard layout.
26094 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
26096 The initrd is automatically populated with all the kernel modules necessary
26097 for @var{file-systems} and for the given options. Additional kernel
26098 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
26099 loaded at boot time in the order in which they appear.
26102 Needless to say, the initrds we produce and use embed a
26103 statically-linked Guile, and the initialization program is a Guile
26104 program. That gives a lot of flexibility. The
26105 @code{expression->initrd} procedure builds such an initrd, given the
26106 program to run in that initrd.
26108 @deffn {Scheme Procedure} expression->initrd @var{exp} @
26109 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
26110 Return as a file-like object a Linux initrd (a gzipped cpio archive)
26111 containing @var{guile} and that evaluates @var{exp}, a G-expression,
26112 upon booting. All the derivations referenced by @var{exp} are
26113 automatically copied to the initrd.
26116 @node Bootloader Configuration
26117 @section Bootloader Configuration
26120 @cindex boot loader
26122 The operating system supports multiple bootloaders. The bootloader is
26123 configured using @code{bootloader-configuration} declaration. All the
26124 fields of this structure are bootloader agnostic except for one field,
26125 @code{bootloader} that indicates the bootloader to be configured and
26128 Some of the bootloaders do not honor every field of
26129 @code{bootloader-configuration}. For instance, the extlinux
26130 bootloader does not support themes and thus ignores the @code{theme}
26133 @deftp {Data Type} bootloader-configuration
26134 The type of a bootloader configuration declaration.
26138 @item @code{bootloader}
26139 @cindex EFI, bootloader
26140 @cindex UEFI, bootloader
26141 @cindex BIOS, bootloader
26142 The bootloader to use, as a @code{bootloader} object. For now
26143 @code{grub-bootloader}, @code{grub-efi-bootloader},
26144 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
26146 @vindex grub-efi-bootloader
26147 @code{grub-efi-bootloader} allows to boot on modern systems using the
26148 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
26149 use if the installation image contains a @file{/sys/firmware/efi} directory
26150 when you boot it on your system.
26152 @vindex grub-bootloader
26153 @code{grub-bootloader} allows you to boot in particular Intel-based machines
26154 in ``legacy'' BIOS mode.
26156 @cindex ARM, bootloaders
26157 @cindex AArch64, bootloaders
26158 Available bootloaders are described in @code{(gnu bootloader @dots{})}
26159 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
26160 of bootloaders for a wide range of ARM and AArch64 systems, using the
26161 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
26163 @item @code{target}
26164 This is a string denoting the target onto which to install the
26167 The interpretation depends on the bootloader in question. For
26168 @code{grub-bootloader}, for example, it should be a device name understood by
26169 the bootloader @command{installer} command, such as @code{/dev/sda} or
26170 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
26171 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
26172 system, usually @file{/boot/efi}.
26174 @item @code{menu-entries} (default: @code{()})
26175 A possibly empty list of @code{menu-entry} objects (see below), denoting
26176 entries to appear in the bootloader menu, in addition to the current
26177 system entry and the entry pointing to previous system generations.
26179 @item @code{default-entry} (default: @code{0})
26180 The index of the default boot menu entry. Index 0 is for the entry of the
26183 @item @code{timeout} (default: @code{5})
26184 The number of seconds to wait for keyboard input before booting. Set to
26185 0 to boot immediately, and to -1 to wait indefinitely.
26187 @cindex keyboard layout, for the bootloader
26188 @item @code{keyboard-layout} (default: @code{#f})
26189 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
26190 layout, usually US@tie{}English (``qwerty'').
26192 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
26196 This option is currently ignored by bootloaders other than @code{grub} and
26200 @item @code{theme} (default: @var{#f})
26201 The bootloader theme object describing the theme to use. If no theme
26202 is provided, some bootloaders might use a default theme, that's true
26205 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
26206 The output terminals used for the bootloader boot menu, as a list of
26207 symbols. GRUB accepts the values: @code{console}, @code{serial},
26208 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
26209 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
26210 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
26211 configuration,,, grub,GNU GRUB manual}).
26213 @item @code{terminal-inputs} (default: @code{'()})
26214 The input terminals used for the bootloader boot menu, as a list of
26215 symbols. For GRUB, the default is the native platform terminal as
26216 determined at run-time. GRUB accepts the values: @code{console},
26217 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
26218 @code{usb_keyboard}. This field corresponds to the GRUB variable
26219 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
26222 @item @code{serial-unit} (default: @code{#f})
26223 The serial unit used by the bootloader, as an integer from 0 to 3.
26224 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
26225 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26227 @item @code{serial-speed} (default: @code{#f})
26228 The speed of the serial interface, as an integer. For GRUB, the
26229 default value is chosen at run-time; currently GRUB chooses
26230 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
26237 Should you want to list additional boot menu entries @i{via} the
26238 @code{menu-entries} field above, you will need to create them with the
26239 @code{menu-entry} form. For example, imagine you want to be able to
26240 boot another distro (hard to imagine!), you can define a menu entry
26245 (label "The Other Distro")
26246 (linux "/boot/old/vmlinux-2.6.32")
26247 (linux-arguments '("root=/dev/sda2"))
26248 (initrd "/boot/old/initrd"))
26253 @deftp {Data Type} menu-entry
26254 The type of an entry in the bootloader menu.
26259 The label to show in the menu---e.g., @code{"GNU"}.
26262 The Linux kernel image to boot, for example:
26265 (file-append linux-libre "/bzImage")
26268 For GRUB, it is also possible to specify a device explicitly in the
26269 file path using GRUB's device naming convention (@pxref{Naming
26270 convention,,, grub, GNU GRUB manual}), for example:
26273 "(hd0,msdos1)/boot/vmlinuz"
26276 If the device is specified explicitly as above, then the @code{device}
26277 field is ignored entirely.
26279 @item @code{linux-arguments} (default: @code{()})
26280 The list of extra Linux kernel command-line arguments---e.g.,
26281 @code{("console=ttyS0")}.
26283 @item @code{initrd}
26284 A G-Expression or string denoting the file name of the initial RAM disk
26285 to use (@pxref{G-Expressions}).
26286 @item @code{device} (default: @code{#f})
26287 The device where the kernel and initrd are to be found---i.e., for GRUB,
26288 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
26290 This may be a file system label (a string), a file system UUID (a
26291 bytevector, @pxref{File Systems}), or @code{#f}, in which case
26292 the bootloader will search the device containing the file specified by
26293 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
26294 must @emph{not} be an OS device name such as @file{/dev/sda1}.
26302 @c FIXME: Write documentation once it's stable.
26303 For now only GRUB has theme support. GRUB themes are created using
26304 the @code{grub-theme} form, which is not fully documented yet.
26306 @deftp {Data Type} grub-theme
26307 Data type representing the configuration of the GRUB theme.
26310 @item @code{gfxmode} (default: @code{'("auto")})
26311 The GRUB @code{gfxmode} to set (a list of screen resolution strings, see
26312 @pxref{gfxmode,,, grub, GNU GRUB manual}).
26316 @defvr {Scheme Variable} %default-theme
26317 This is the default GRUB theme used by the operating system if no
26318 @code{theme} field is specified in @code{bootloader-configuration}
26321 It comes with a fancy background image displaying the GNU and Guix
26325 For example, to override the default resolution, you may use something
26330 (grub-configuration
26333 (inherit %default-theme)
26334 (gfxmode '("1024x786x32" "auto"))))))
26337 @node Invoking guix system
26338 @section Invoking @code{guix system}
26340 Once you have written an operating system declaration as seen in the
26341 previous section, it can be @dfn{instantiated} using the @command{guix
26342 system} command. The synopsis is:
26345 guix system @var{options}@dots{} @var{action} @var{file}
26348 @var{file} must be the name of a file containing an
26349 @code{operating-system} declaration. @var{action} specifies how the
26350 operating system is instantiated. Currently the following values are
26355 Display available service type definitions that match the given regular
26356 expressions, sorted by relevance:
26362 $ guix system search console
26363 name: console-fonts
26364 location: gnu/services/base.scm:806:2
26365 extends: shepherd-root
26366 description: Install the given fonts on the specified ttys (fonts are per
26367 + virtual console on GNU/Linux). The value of this service is a list of
26368 + tty/font pairs. The font can be the name of a font provided by the `kbd'
26369 + package or any valid argument to `setfont', as in this example:
26371 + '(("tty1" . "LatGrkCyr-8x16")
26372 + ("tty2" . (file-append
26374 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
26375 + ("tty3" . (file-append
26377 + "/share/consolefonts/ter-132n"))) ; for HDPI
26381 location: gnu/services/base.scm:1190:2
26382 extends: shepherd-root
26383 description: Provide console login using the `mingetty' program.
26387 location: gnu/services/base.scm:860:2
26389 description: Provide a console log-in service as specified by its
26390 + configuration value, a `login-configuration' object.
26396 As for @command{guix package --search}, the result is written in
26397 @code{recutils} format, which makes it easy to filter the output
26398 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
26401 Build the operating system described in @var{file}, activate it, and
26402 switch to it@footnote{This action (and the related actions
26403 @code{switch-generation} and @code{roll-back}) are usable only on
26404 systems already running Guix System.}.
26407 @c The paragraph below refers to the problem discussed at
26408 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
26409 It is highly recommended to run @command{guix pull} once before you run
26410 @command{guix system reconfigure} for the first time (@pxref{Invoking
26411 guix pull}). Failing to do that you would see an older version of Guix
26412 once @command{reconfigure} has completed.
26415 This effects all the configuration specified in @var{file}: user
26416 accounts, system services, global package list, setuid programs, etc.
26417 The command starts system services specified in @var{file} that are not
26418 currently running; if a service is currently running this command will
26419 arrange for it to be upgraded the next time it is stopped (e.g.@: by
26420 @code{herd stop X} or @code{herd restart X}).
26422 This command creates a new generation whose number is one greater than
26423 the current generation (as reported by @command{guix system
26424 list-generations}). If that generation already exists, it will be
26425 overwritten. This behavior mirrors that of @command{guix package}
26426 (@pxref{Invoking guix package}).
26428 It also adds a bootloader menu entry for the new OS configuration,
26429 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
26430 entries for older configurations to a submenu, allowing you to choose
26431 an older system generation at boot time should you need it.
26433 @cindex provenance tracking, of the operating system
26434 Upon completion, the new system is deployed under
26435 @file{/run/current-system}. This directory contains @dfn{provenance
26436 meta-data}: the list of channels in use (@pxref{Channels}) and
26437 @var{file} itself, when available. This information is useful should
26438 you later want to inspect how this particular generation was built.
26440 In fact, assuming @var{file} is self-contained, you can later rebuild
26441 generation @var{n} of your operating system with:
26444 guix time-machine \
26445 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
26446 system reconfigure \
26447 /var/guix/profiles/system-@var{n}-link/configuration.scm
26450 You can think of it as some sort of built-in version control! Your
26451 system is not just a binary artifact: @emph{it carries its own source}.
26452 @xref{Service Reference, @code{provenance-service-type}}, for more
26453 information on provenance tracking.
26455 @item switch-generation
26456 @cindex generations
26457 Switch to an existing system generation. This action atomically
26458 switches the system profile to the specified system generation. It
26459 also rearranges the system's existing bootloader menu entries. It
26460 makes the menu entry for the specified system generation the default,
26461 and it moves the entries for the other generations to a submenu, if
26462 supported by the bootloader being used. The next time the system
26463 boots, it will use the specified system generation.
26465 The bootloader itself is not being reinstalled when using this
26466 command. Thus, the installed bootloader is used with an updated
26467 configuration file.
26469 The target generation can be specified explicitly by its generation
26470 number. For example, the following invocation would switch to system
26474 guix system switch-generation 7
26477 The target generation can also be specified relative to the current
26478 generation with the form @code{+N} or @code{-N}, where @code{+3} means
26479 ``3 generations ahead of the current generation,'' and @code{-1} means
26480 ``1 generation prior to the current generation.'' When specifying a
26481 negative value such as @code{-1}, you must precede it with @code{--} to
26482 prevent it from being parsed as an option. For example:
26485 guix system switch-generation -- -1
26488 Currently, the effect of invoking this action is @emph{only} to switch
26489 the system profile to an existing generation and rearrange the
26490 bootloader menu entries. To actually start using the target system
26491 generation, you must reboot after running this action. In the future,
26492 it will be updated to do the same things as @command{reconfigure},
26493 like activating and deactivating services.
26495 This action will fail if the specified generation does not exist.
26498 @cindex rolling back
26499 Switch to the preceding system generation. The next time the system
26500 boots, it will use the preceding system generation. This is the inverse
26501 of @command{reconfigure}, and it is exactly the same as invoking
26502 @command{switch-generation} with an argument of @code{-1}.
26504 Currently, as with @command{switch-generation}, you must reboot after
26505 running this action to actually start using the preceding system
26508 @item delete-generations
26509 @cindex deleting system generations
26510 @cindex saving space
26511 Delete system generations, making them candidates for garbage collection
26512 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
26515 This works in the same way as @command{guix package --delete-generations}
26516 (@pxref{Invoking guix package, @code{--delete-generations}}). With no
26517 arguments, all system generations but the current one are deleted:
26520 guix system delete-generations
26523 You can also select the generations you want to delete. The example below
26524 deletes all the system generations that are more than two month old:
26527 guix system delete-generations 2m
26530 Running this command automatically reinstalls the bootloader with an updated
26531 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
26532 longer lists the generations that have been deleted.
26535 Build the derivation of the operating system, which includes all the
26536 configuration files and programs needed to boot and run the system.
26537 This action does not actually install anything.
26540 Populate the given directory with all the files necessary to run the
26541 operating system specified in @var{file}. This is useful for first-time
26542 installations of Guix System. For instance:
26545 guix system init my-os-config.scm /mnt
26548 copies to @file{/mnt} all the store items required by the configuration
26549 specified in @file{my-os-config.scm}. This includes configuration
26550 files, packages, and so on. It also creates other essential files
26551 needed for the system to operate correctly---e.g., the @file{/etc},
26552 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
26554 This command also installs bootloader on the target specified in
26555 @file{my-os-config}, unless the @option{--no-bootloader} option was
26559 @cindex virtual machine
26561 @anchor{guix system vm}
26562 Build a virtual machine that contains the operating system declared in
26563 @var{file}, and return a script to run that virtual machine (VM).
26566 The @code{vm} action and others below
26567 can use KVM support in the Linux-libre kernel. Specifically, if the
26568 machine has hardware virtualization support, the corresponding
26569 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
26570 must exist and be readable and writable by the user and by the
26571 build users of the daemon (@pxref{Build Environment Setup}).
26574 Arguments given to the script are passed to QEMU as in the example
26575 below, which enables networking and requests 1@tie{}GiB of RAM for the
26579 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
26582 The VM shares its store with the host system.
26584 Additional file systems can be shared between the host and the VM using
26585 the @code{--share} and @code{--expose} command-line options: the former
26586 specifies a directory to be shared with write access, while the latter
26587 provides read-only access to the shared directory.
26589 The example below creates a VM in which the user's home directory is
26590 accessible read-only, and where the @file{/exchange} directory is a
26591 read-write mapping of @file{$HOME/tmp} on the host:
26594 guix system vm my-config.scm \
26595 --expose=$HOME --share=$HOME/tmp=/exchange
26598 On GNU/Linux, the default is to boot directly to the kernel; this has
26599 the advantage of requiring only a very tiny root disk image since the
26600 store of the host can then be mounted.
26602 The @code{--full-boot} option forces a complete boot sequence, starting
26603 with the bootloader. This requires more disk space since a root image
26604 containing at least the kernel, initrd, and bootloader data files must
26605 be created. The @code{--image-size} option can be used to specify the
26608 @cindex System images, creation in various formats
26609 @cindex Creating system images in various formats
26612 @itemx docker-image
26613 Return a virtual machine, disk image, or Docker image of the operating
26614 system declared in @var{file} that stands alone. By default,
26615 @command{guix system} estimates the size of the image needed to store
26616 the system, but you can use the @option{--image-size} option to specify
26617 a value. Docker images are built to contain exactly what they need, so
26618 the @option{--image-size} option is ignored in the case of
26619 @code{docker-image}.
26621 You can specify the root file system type by using the
26622 @option{--file-system-type} option. It defaults to @code{ext4}.
26624 When using @code{vm-image}, the returned image is in qcow2 format, which
26625 the QEMU emulator can efficiently use. @xref{Running Guix in a VM},
26626 for more information on how to run the image in a virtual machine.
26628 When using @code{disk-image}, a raw disk image is produced; it can be
26629 copied as is to a USB stick, for instance. Assuming @code{/dev/sdc} is
26630 the device corresponding to a USB stick, one can copy the image to it
26631 using the following command:
26634 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc
26637 When using @code{docker-image}, a Docker image is produced. Guix builds
26638 the image from scratch, not from a pre-existing Docker base image. As a
26639 result, it contains @emph{exactly} what you define in the operating
26640 system configuration file. You can then load the image and launch a
26641 Docker container using commands like the following:
26644 image_id="`docker load < guix-system-docker-image.tar.gz`"
26645 container_id="`docker create $image_id`"
26646 docker start $container_id
26649 This command starts a new Docker container from the specified image. It
26650 will boot the Guix system in the usual manner, which means it will
26651 start any services you have defined in the operating system
26652 configuration. You can get an interactive shell running in the container
26653 using @command{docker exec}:
26656 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
26659 Depending on what you run in the Docker container, it
26660 may be necessary to give the container additional permissions. For
26661 example, if you intend to build software using Guix inside of the Docker
26662 container, you may need to pass the @option{--privileged} option to
26663 @code{docker create}.
26666 Return a script to run the operating system declared in @var{file}
26667 within a container. Containers are a set of lightweight isolation
26668 mechanisms provided by the kernel Linux-libre. Containers are
26669 substantially less resource-demanding than full virtual machines since
26670 the kernel, shared objects, and other resources can be shared with the
26671 host system; this also means they provide thinner isolation.
26673 Currently, the script must be run as root in order to support more than
26674 a single user and group. The container shares its store with the host
26677 As with the @code{vm} action (@pxref{guix system vm}), additional file
26678 systems to be shared between the host and container can be specified
26679 using the @option{--share} and @option{--expose} options:
26682 guix system container my-config.scm \
26683 --expose=$HOME --share=$HOME/tmp=/exchange
26687 This option requires Linux-libre 3.19 or newer.
26692 @var{options} can contain any of the common build options (@pxref{Common
26693 Build Options}). In addition, @var{options} can contain one of the
26697 @item --expression=@var{expr}
26698 @itemx -e @var{expr}
26699 Consider the operating-system @var{expr} evaluates to.
26700 This is an alternative to specifying a file which evaluates to an
26702 This is used to generate the Guix system installer @pxref{Building the
26703 Installation Image}).
26705 @item --system=@var{system}
26706 @itemx -s @var{system}
26707 Attempt to build for @var{system} instead of the host system type.
26708 This works as per @command{guix build} (@pxref{Invoking guix build}).
26712 Return the derivation file name of the given operating system without
26715 @cindex provenance tracking, of the operating system
26716 @item --save-provenance
26717 As discussed above, @command{guix system init} and @command{guix system
26718 reconfigure} always save provenance information @i{via} a dedicated
26719 service (@pxref{Service Reference, @code{provenance-service-type}}).
26720 However, other commands don't do that by default. If you wish to, say,
26721 create a virtual machine image that contains provenance information, you
26725 guix system vm-image --save-provenance config.scm
26728 That way, the resulting image will effectively ``embed its own source''
26729 in the form of meta-data in @file{/run/current-system}. With that
26730 information, one can rebuild the image to make sure it really contains
26731 what it pretends to contain; or they could use that to derive a variant
26734 @item --file-system-type=@var{type}
26735 @itemx -t @var{type}
26736 For the @code{disk-image} action, create a file system of the given
26737 @var{type} on the image.
26739 When this option is omitted, @command{guix system} uses @code{ext4}.
26741 @cindex ISO-9660 format
26742 @cindex CD image format
26743 @cindex DVD image format
26744 @code{--file-system-type=iso9660} produces an ISO-9660 image, suitable
26745 for burning on CDs and DVDs.
26747 @item --image-size=@var{size}
26748 For the @code{vm-image} and @code{disk-image} actions, create an image
26749 of the given @var{size}. @var{size} may be a number of bytes, or it may
26750 include a unit as a suffix (@pxref{Block size, size specifications,,
26751 coreutils, GNU Coreutils}).
26753 When this option is omitted, @command{guix system} computes an estimate
26754 of the image size as a function of the size of the system declared in
26759 For the @code{container} action, allow containers to access the host network,
26760 that is, do not create a network namespace.
26762 @item --root=@var{file}
26763 @itemx -r @var{file}
26764 Make @var{file} a symlink to the result, and register it as a garbage
26767 @item --skip-checks
26768 Skip pre-installation safety checks.
26770 By default, @command{guix system init} and @command{guix system
26771 reconfigure} perform safety checks: they make sure the file systems that
26772 appear in the @code{operating-system} declaration actually exist
26773 (@pxref{File Systems}), and that any Linux kernel modules that may be
26774 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
26775 RAM Disk}). Passing this option skips these tests altogether.
26778 @cindex on-error strategy
26779 @cindex error strategy
26780 @item --on-error=@var{strategy}
26781 Apply @var{strategy} when an error occurs when reading @var{file}.
26782 @var{strategy} may be one of the following:
26785 @item nothing-special
26786 Report the error concisely and exit. This is the default strategy.
26789 Likewise, but also display a backtrace.
26792 Report the error and enter Guile's debugger. From there, you can run
26793 commands such as @code{,bt} to get a backtrace, @code{,locals} to
26794 display local variable values, and more generally inspect the state of the
26795 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
26796 a list of available debugging commands.
26800 Once you have built, configured, re-configured, and re-re-configured
26801 your Guix installation, you may find it useful to list the operating
26802 system generations available on disk---and that you can choose from the
26803 bootloader boot menu:
26808 Describe the current system generation: its file name, the kernel and
26809 bootloader used, etc., as well as provenance information when available.
26811 @item list-generations
26812 List a summary of each generation of the operating system available on
26813 disk, in a human-readable way. This is similar to the
26814 @option{--list-generations} option of @command{guix package}
26815 (@pxref{Invoking guix package}).
26817 Optionally, one can specify a pattern, with the same syntax that is used
26818 in @command{guix package --list-generations}, to restrict the list of
26819 generations displayed. For instance, the following command displays
26820 generations that are up to 10 days old:
26823 $ guix system list-generations 10d
26828 The @command{guix system} command has even more to offer! The following
26829 sub-commands allow you to visualize how your system services relate to
26832 @anchor{system-extension-graph}
26835 @item extension-graph
26836 Emit in Dot/Graphviz format to standard output the @dfn{service
26837 extension graph} of the operating system defined in @var{file}
26838 (@pxref{Service Composition}, for more information on service
26844 $ guix system extension-graph @var{file} | dot -Tpdf > services.pdf
26847 produces a PDF file showing the extension relations among services.
26849 @anchor{system-shepherd-graph}
26850 @item shepherd-graph
26851 Emit in Dot/Graphviz format to standard output the @dfn{dependency
26852 graph} of shepherd services of the operating system defined in
26853 @var{file}. @xref{Shepherd Services}, for more information and for an
26858 @node Invoking guix deploy
26859 @section Invoking @code{guix deploy}
26861 We've already seen @code{operating-system} declarations used to manage a
26862 machine's configuration locally. Suppose you need to configure multiple
26863 machines, though---perhaps you're managing a service on the web that's
26864 comprised of several servers. @command{guix deploy} enables you to use those
26865 same @code{operating-system} declarations to manage multiple remote hosts at
26866 once as a logical ``deployment''.
26869 The functionality described in this section is still under development
26870 and is subject to change. Get in touch with us on
26871 @email{guix-devel@@gnu.org}!
26875 guix deploy @var{file}
26878 Such an invocation will deploy the machines that the code within @var{file}
26879 evaluates to. As an example, @var{file} might contain a definition like this:
26882 ;; This is a Guix deployment of a "bare bones" setup, with
26883 ;; no X11 display server, to a machine with an SSH daemon
26884 ;; listening on localhost:2222. A configuration such as this
26885 ;; may be appropriate for virtual machine with ports
26886 ;; forwarded to the host's loopback interface.
26888 (use-service-modules networking ssh)
26889 (use-package-modules bootloaders)
26893 (host-name "gnu-deployed")
26894 (timezone "Etc/UTC")
26895 (bootloader (bootloader-configuration
26896 (bootloader grub-bootloader)
26897 (target "/dev/vda")
26898 (terminal-outputs '(console))))
26899 (file-systems (cons (file-system
26901 (device "/dev/vda1")
26903 %base-file-systems))
26905 (append (list (service dhcp-client-service-type)
26906 (service openssh-service-type
26907 (openssh-configuration
26908 (permit-root-login #t)
26909 (allow-empty-passwords? #t))))
26913 (operating-system %system)
26914 (environment managed-host-environment-type)
26915 (configuration (machine-ssh-configuration
26916 (host-name "localhost")
26917 (system "x86_64-linux")
26919 (identity "./id_rsa")
26923 The file should evaluate to a list of @var{machine} objects. This example,
26924 upon being deployed, will create a new generation on the remote system
26925 realizing the @code{operating-system} declaration @var{%system}.
26926 @var{environment} and @var{configuration} specify how the machine should be
26927 provisioned---that is, how the computing resources should be created and
26928 managed. The above example does not create any resources, as a
26929 @code{'managed-host} is a machine that is already running the Guix system and
26930 available over the network. This is a particularly simple case; a more
26931 complex deployment may involve, for example, starting virtual machines through
26932 a Virtual Private Server (VPS) provider. In such a case, a different
26933 @var{environment} type would be used.
26935 Do note that you first need to generate a key pair on the coordinator machine
26936 to allow the daemon to export signed archives of files from the store
26937 (@pxref{Invoking guix archive}).
26940 # guix archive --generate-key
26944 Each target machine must authorize the key of the master machine so that it
26945 accepts store items it receives from the coordinator:
26948 # guix archive --authorize < coordinator-public-key.txt
26951 @code{user}, in this example, specifies the name of the user account to log in
26952 as to perform the deployment. Its default value is @code{root}, but root
26953 login over SSH may be forbidden in some cases. To work around this,
26954 @command{guix deploy} can log in as an unprivileged user and employ
26955 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
26956 currently installed on the remote and can be invoked non-interactively as
26957 @code{user}. That is: the line in @code{sudoers} granting @code{user} the
26958 ability to use @code{sudo} must contain the @code{NOPASSWD} tag.
26960 @deftp {Data Type} machine
26961 This is the data type representing a single machine in a heterogeneous Guix
26965 @item @code{operating-system}
26966 The object of the operating system configuration to deploy.
26968 @item @code{environment}
26969 An @code{environment-type} describing how the machine should be provisioned.
26971 @item @code{configuration} (default: @code{#f})
26972 An object describing the configuration for the machine's @code{environment}.
26973 If the @code{environment} has a default configuration, @code{#f} may be used.
26974 If @code{#f} is used for an environment with no default configuration,
26975 however, an error will be thrown.
26979 @deftp {Data Type} machine-ssh-configuration
26980 This is the data type representing the SSH client parameters for a machine
26981 with an @code{environment} of @code{managed-host-environment-type}.
26984 @item @code{host-name}
26985 @item @code{build-locally?} (default: @code{#t})
26986 If false, system derivations will be built on the machine being deployed to.
26987 @item @code{system}
26988 The system type describing the architecture of the machine being deployed
26989 to---e.g., @code{"x86_64-linux"}.
26990 @item @code{authorize?} (default: @code{#t})
26991 If true, the coordinator's signing key will be added to the remote's ACL
26993 @item @code{port} (default: @code{22})
26994 @item @code{user} (default: @code{"root"})
26995 @item @code{identity} (default: @code{#f})
26996 If specified, the path to the SSH private key to use to authenticate with the
26999 @item @code{host-key} (default: @code{#f})
27000 This should be the SSH host key of the machine, which looks like this:
27003 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
27006 When @code{host-key} is @code{#f}, the server is authenticated against
27007 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
27013 @deftp {Data Type} digital-ocean-configuration
27014 This is the data type describing the Droplet that should be created for a
27015 machine with an @code{environment} of @code{digital-ocean-environment-type}.
27018 @item @code{ssh-key}
27019 The path to the SSH private key to use to authenticate with the remote
27020 host. In the future, this field may not exist.
27022 A list of string ``tags'' that uniquely identify the machine. Must be given
27023 such that no two machines in the deployment have the same set of tags.
27024 @item @code{region}
27025 A Digital Ocean region slug, such as @code{"nyc3"}.
27027 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
27028 @item @code{enable-ipv6?}
27029 Whether or not the droplet should be created with IPv6 networking.
27033 @node Running Guix in a VM
27034 @section Running Guix in a Virtual Machine
27036 @cindex virtual machine
27037 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
27039 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
27040 This image is a compressed image in QCOW format. You will first need to
27041 decompress with @command{xz -d}, and then you can pass it to an emulator such
27042 as QEMU (see below for details).
27044 This image boots the Xfce graphical environment and it contains some
27045 commonly-used tools. You can install more software in the image by running
27046 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
27047 also reconfigure the system based on its initial configuration file available
27048 as @file{/etc/config.scm} (@pxref{Using the Configuration System}).
27050 Instead of using this pre-built image, one can also build their own virtual
27051 machine image using @command{guix system vm-image} (@pxref{Invoking guix
27052 system}). The returned image is in qcow2 format, which the
27053 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
27056 If you built your own image, you must copy it out of the store
27057 (@pxref{The Store}) and give yourself permission to write to the copy
27058 before you can use it. When invoking QEMU, you must choose a system
27059 emulator that is suitable for your hardware platform. Here is a minimal
27060 QEMU invocation that will boot the result of @command{guix system
27061 vm-image} on x86_64 hardware:
27064 $ qemu-system-x86_64 \
27065 -nic user,model=virtio-net-pci \
27066 -enable-kvm -m 1024 \
27067 -device virtio-blk,drive=myhd \
27068 -drive if=none,file=/tmp/qemu-image,id=myhd
27071 Here is what each of these options means:
27074 @item qemu-system-x86_64
27075 This specifies the hardware platform to emulate. This should match the
27078 @item -nic user,model=virtio-net-pci
27079 Enable the unprivileged user-mode network stack. The guest OS can
27080 access the host but not vice versa. This is the simplest way to get the
27081 guest OS online. @code{model} specifies which network device to emulate:
27082 @code{virtio-net-pci} is a special device made for virtualized operating
27083 systems and recommended for most uses. Assuming your hardware platform is
27084 x86_64, you can get a list of available NIC models by running
27085 @command{qemu-system-x86_64 -nic model=help}.
27088 If your system has hardware virtualization extensions, enabling the
27089 virtual machine support (KVM) of the Linux kernel will make things run
27092 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
27094 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
27095 which may be insufficient for some operations.
27097 @item -device virtio-blk,drive=myhd
27098 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
27099 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
27100 better performance than if it were emulating a complete disk drive. See the
27101 QEMU and KVM documentation for more info.
27103 @item -drive if=none,file=/tmp/qemu-image,id=myhd
27104 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing store the
27105 the ``myhd'' drive.
27108 The default @command{run-vm.sh} script that is returned by an invocation of
27109 @command{guix system vm} does not add a @command{-nic user} flag by default.
27110 To get network access from within the vm add the @code{(dhcp-client-service)}
27111 to your system definition and start the VM using
27112 @command{`guix system vm config.scm` -nic user}. An important caveat of using
27113 @command{-nic user} for networking is that @command{ping} will not work, because
27114 it uses the ICMP protocol. You'll have to use a different command to check for
27115 network connectivity, for example @command{guix download}.
27117 @subsection Connecting Through SSH
27121 To enable SSH inside a VM you need to add an SSH server like
27122 @code{openssh-service-type} to your VM (@pxref{Networking Services,
27123 @code{openssh-service-type}}). In addition you need to forward the SSH port,
27124 22 by default, to the host. You can do this with
27127 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
27130 To connect to the VM you can run
27133 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
27136 The @command{-p} tells @command{ssh} the port you want to connect to.
27137 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
27138 every time you modify your @command{config.scm} file and the
27139 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
27140 connection to an unknown host every time you connect.
27142 @subsection Using @command{virt-viewer} with Spice
27144 As an alternative to the default @command{qemu} graphical client you can
27145 use the @command{remote-viewer} from the @command{virt-viewer} package. To
27146 connect pass the @command{-spice port=5930,disable-ticketing} flag to
27147 @command{qemu}. See previous section for further information on how to do this.
27149 Spice also allows you to do some nice stuff like share your clipboard with your
27150 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
27153 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
27154 -chardev spicevmc,name=vdagent,id=vdagent
27155 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
27156 name=com.redhat.spice.0
27159 You'll also need to add the @pxref{Miscellaneous Services, Spice service}.
27161 @node Defining Services
27162 @section Defining Services
27164 The previous sections show the available services and how one can combine
27165 them in an @code{operating-system} declaration. But how do we define
27166 them in the first place? And what is a service anyway?
27169 * Service Composition:: The model for composing services.
27170 * Service Types and Services:: Types and services.
27171 * Service Reference:: API reference.
27172 * Shepherd Services:: A particular type of service.
27175 @node Service Composition
27176 @subsection Service Composition
27180 Here we define a @dfn{service} as, broadly, something that extends the
27181 functionality of the operating system. Often a service is a process---a
27182 @dfn{daemon}---started when the system boots: a secure shell server, a
27183 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
27184 whose execution can be triggered by another daemon---e.g., an FTP server
27185 started by @command{inetd} or a D-Bus service activated by
27186 @command{dbus-daemon}. Occasionally, a service does not map to a
27187 daemon. For instance, the ``account'' service collects user accounts
27188 and makes sure they exist when the system runs; the ``udev'' service
27189 collects device management rules and makes them available to the eudev
27190 daemon; the @file{/etc} service populates the @file{/etc} directory
27193 @cindex service extensions
27194 Guix system services are connected by @dfn{extensions}. For instance, the
27195 secure shell service @emph{extends} the Shepherd---the
27196 initialization system, running as PID@tie{}1---by giving it the command
27197 lines to start and stop the secure shell daemon (@pxref{Networking
27198 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
27199 service by passing it its @file{.service} specification, and extends the
27200 udev service by passing it device management rules (@pxref{Desktop
27201 Services, @code{upower-service}}); the Guix daemon service extends the
27202 Shepherd by passing it the command lines to start and stop the daemon,
27203 and extends the account service by passing it a list of required build
27204 user accounts (@pxref{Base Services}).
27206 All in all, services and their ``extends'' relations form a directed
27207 acyclic graph (DAG). If we represent services as boxes and extensions
27208 as arrows, a typical system might provide something like this:
27210 @image{images/service-graph,,5in,Typical service extension graph.}
27212 @cindex system service
27213 At the bottom, we see the @dfn{system service}, which produces the
27214 directory containing everything to run and boot the system, as returned
27215 by the @command{guix system build} command. @xref{Service Reference},
27216 to learn about the other service types shown here.
27217 @xref{system-extension-graph, the @command{guix system extension-graph}
27218 command}, for information on how to generate this representation for a
27219 particular operating system definition.
27221 @cindex service types
27222 Technically, developers can define @dfn{service types} to express these
27223 relations. There can be any number of services of a given type on the
27224 system---for instance, a system running two instances of the GNU secure
27225 shell server (lsh) has two instances of @code{lsh-service-type}, with
27226 different parameters.
27228 The following section describes the programming interface for service
27229 types and services.
27231 @node Service Types and Services
27232 @subsection Service Types and Services
27234 A @dfn{service type} is a node in the DAG described above. Let us start
27235 with a simple example, the service type for the Guix build daemon
27236 (@pxref{Invoking guix-daemon}):
27239 (define guix-service-type
27243 (list (service-extension shepherd-root-service-type guix-shepherd-service)
27244 (service-extension account-service-type guix-accounts)
27245 (service-extension activation-service-type guix-activation)))
27246 (default-value (guix-configuration))))
27250 It defines three things:
27254 A name, whose sole purpose is to make inspection and debugging easier.
27257 A list of @dfn{service extensions}, where each extension designates the
27258 target service type and a procedure that, given the parameters of the
27259 service, returns a list of objects to extend the service of that type.
27261 Every service type has at least one service extension. The only
27262 exception is the @dfn{boot service type}, which is the ultimate service.
27265 Optionally, a default value for instances of this type.
27268 In this example, @code{guix-service-type} extends three services:
27271 @item shepherd-root-service-type
27272 The @code{guix-shepherd-service} procedure defines how the Shepherd
27273 service is extended. Namely, it returns a @code{<shepherd-service>}
27274 object that defines how @command{guix-daemon} is started and stopped
27275 (@pxref{Shepherd Services}).
27277 @item account-service-type
27278 This extension for this service is computed by @code{guix-accounts},
27279 which returns a list of @code{user-group} and @code{user-account}
27280 objects representing the build user accounts (@pxref{Invoking
27283 @item activation-service-type
27284 Here @code{guix-activation} is a procedure that returns a gexp, which is
27285 a code snippet to run at ``activation time''---e.g., when the service is
27289 A service of this type is instantiated like this:
27292 (service guix-service-type
27293 (guix-configuration
27295 (use-substitutes? #f)))
27298 The second argument to the @code{service} form is a value representing
27299 the parameters of this specific service instance.
27300 @xref{guix-configuration-type, @code{guix-configuration}}, for
27301 information about the @code{guix-configuration} data type. When the
27302 value is omitted, the default value specified by
27303 @code{guix-service-type} is used:
27306 (service guix-service-type)
27309 @code{guix-service-type} is quite simple because it extends other
27310 services but is not extensible itself.
27312 @c @subsubsubsection Extensible Service Types
27314 The service type for an @emph{extensible} service looks like this:
27317 (define udev-service-type
27318 (service-type (name 'udev)
27320 (list (service-extension shepherd-root-service-type
27321 udev-shepherd-service)))
27323 (compose concatenate) ;concatenate the list of rules
27324 (extend (lambda (config rules)
27326 (($ <udev-configuration> udev initial-rules)
27327 (udev-configuration
27328 (udev udev) ;the udev package to use
27329 (rules (append initial-rules rules)))))))))
27332 This is the service type for the
27333 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
27334 management daemon}. Compared to the previous example, in addition to an
27335 extension of @code{shepherd-root-service-type}, we see two new fields:
27339 This is the procedure to @dfn{compose} the list of extensions to
27340 services of this type.
27342 Services can extend the udev service by passing it lists of rules; we
27343 compose those extensions simply by concatenating them.
27346 This procedure defines how the value of the service is @dfn{extended} with
27347 the composition of the extensions.
27349 Udev extensions are composed into a list of rules, but the udev service
27350 value is itself a @code{<udev-configuration>} record. So here, we
27351 extend that record by appending the list of rules it contains to the
27352 list of contributed rules.
27355 This is a string giving an overview of the service type. The string can
27356 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
27357 @command{guix system search} command searches these strings and displays
27358 them (@pxref{Invoking guix system}).
27361 There can be only one instance of an extensible service type such as
27362 @code{udev-service-type}. If there were more, the
27363 @code{service-extension} specifications would be ambiguous.
27365 Still here? The next section provides a reference of the programming
27366 interface for services.
27368 @node Service Reference
27369 @subsection Service Reference
27371 We have seen an overview of service types (@pxref{Service Types and
27372 Services}). This section provides a reference on how to manipulate
27373 services and service types. This interface is provided by the
27374 @code{(gnu services)} module.
27376 @deffn {Scheme Procedure} service @var{type} [@var{value}]
27377 Return a new service of @var{type}, a @code{<service-type>} object (see
27378 below.) @var{value} can be any object; it represents the parameters of
27379 this particular service instance.
27381 When @var{value} is omitted, the default value specified by @var{type}
27382 is used; if @var{type} does not specify a default value, an error is
27385 For instance, this:
27388 (service openssh-service-type)
27392 is equivalent to this:
27395 (service openssh-service-type
27396 (openssh-configuration))
27399 In both cases the result is an instance of @code{openssh-service-type}
27400 with the default configuration.
27403 @deffn {Scheme Procedure} service? @var{obj}
27404 Return true if @var{obj} is a service.
27407 @deffn {Scheme Procedure} service-kind @var{service}
27408 Return the type of @var{service}---i.e., a @code{<service-type>} object.
27411 @deffn {Scheme Procedure} service-value @var{service}
27412 Return the value associated with @var{service}. It represents its
27416 Here is an example of how a service is created and manipulated:
27420 (service nginx-service-type
27421 (nginx-configuration
27423 (log-directory log-directory)
27424 (run-directory run-directory)
27425 (file config-file))))
27430 (eq? (service-kind s) nginx-service-type)
27434 The @code{modify-services} form provides a handy way to change the
27435 parameters of some of the services of a list such as
27436 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
27437 evaluates to a list of services. Of course, you could always use
27438 standard list combinators such as @code{map} and @code{fold} to do that
27439 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
27440 @code{modify-services} simply provides a more concise form for this
27443 @deffn {Scheme Syntax} modify-services @var{services} @
27444 (@var{type} @var{variable} => @var{body}) @dots{}
27446 Modify the services listed in @var{services} according to the given
27447 clauses. Each clause has the form:
27450 (@var{type} @var{variable} => @var{body})
27453 where @var{type} is a service type---e.g.,
27454 @code{guix-service-type}---and @var{variable} is an identifier that is
27455 bound within the @var{body} to the service parameters---e.g., a
27456 @code{guix-configuration} instance---of the original service of that
27459 The @var{body} should evaluate to the new service parameters, which will
27460 be used to configure the new service. This new service will replace the
27461 original in the resulting list. Because a service's service parameters
27462 are created using @code{define-record-type*}, you can write a succinct
27463 @var{body} that evaluates to the new service parameters by using the
27464 @code{inherit} feature that @code{define-record-type*} provides.
27466 @xref{Using the Configuration System}, for example usage.
27470 Next comes the programming interface for service types. This is
27471 something you want to know when writing new service definitions, but not
27472 necessarily when simply looking for ways to customize your
27473 @code{operating-system} declaration.
27475 @deftp {Data Type} service-type
27476 @cindex service type
27477 This is the representation of a @dfn{service type} (@pxref{Service Types
27482 This is a symbol, used only to simplify inspection and debugging.
27484 @item @code{extensions}
27485 A non-empty list of @code{<service-extension>} objects (see below).
27487 @item @code{compose} (default: @code{#f})
27488 If this is @code{#f}, then the service type denotes services that cannot
27489 be extended---i.e., services that do not receive ``values'' from other
27492 Otherwise, it must be a one-argument procedure. The procedure is called
27493 by @code{fold-services} and is passed a list of values collected from
27494 extensions. It may return any single value.
27496 @item @code{extend} (default: @code{#f})
27497 If this is @code{#f}, services of this type cannot be extended.
27499 Otherwise, it must be a two-argument procedure: @code{fold-services}
27500 calls it, passing it the initial value of the service as the first
27501 argument and the result of applying @code{compose} to the extension
27502 values as the second argument. It must return a value that is a valid
27503 parameter value for the service instance.
27506 @xref{Service Types and Services}, for examples.
27509 @deffn {Scheme Procedure} service-extension @var{target-type} @
27511 Return a new extension for services of type @var{target-type}.
27512 @var{compute} must be a one-argument procedure: @code{fold-services}
27513 calls it, passing it the value associated with the service that provides
27514 the extension; it must return a valid value for the target service.
27517 @deffn {Scheme Procedure} service-extension? @var{obj}
27518 Return true if @var{obj} is a service extension.
27521 Occasionally, you might want to simply extend an existing service. This
27522 involves creating a new service type and specifying the extension of
27523 interest, which can be verbose; the @code{simple-service} procedure
27524 provides a shorthand for this.
27526 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
27527 Return a service that extends @var{target} with @var{value}. This works
27528 by creating a singleton service type @var{name}, of which the returned
27529 service is an instance.
27531 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
27535 (simple-service 'my-mcron-job mcron-service-type
27536 #~(job '(next-hour (3)) "guix gc -F 2G"))
27540 At the core of the service abstraction lies the @code{fold-services}
27541 procedure, which is responsible for ``compiling'' a list of services
27542 down to a single directory that contains everything needed to boot and
27543 run the system---the directory shown by the @command{guix system build}
27544 command (@pxref{Invoking guix system}). In essence, it propagates
27545 service extensions down the service graph, updating each node parameters
27546 on the way, until it reaches the root node.
27548 @deffn {Scheme Procedure} fold-services @var{services} @
27549 [#:target-type @var{system-service-type}]
27550 Fold @var{services} by propagating their extensions down to the root of
27551 type @var{target-type}; return the root service adjusted accordingly.
27554 Lastly, the @code{(gnu services)} module also defines several essential
27555 service types, some of which are listed below.
27557 @defvr {Scheme Variable} system-service-type
27558 This is the root of the service graph. It produces the system directory
27559 as returned by the @command{guix system build} command.
27562 @defvr {Scheme Variable} boot-service-type
27563 The type of the ``boot service'', which produces the @dfn{boot script}.
27564 The boot script is what the initial RAM disk runs when booting.
27567 @defvr {Scheme Variable} etc-service-type
27568 The type of the @file{/etc} service. This service is used to create
27569 files under @file{/etc} and can be extended by
27570 passing it name/file tuples such as:
27573 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
27576 In this example, the effect would be to add an @file{/etc/issue} file
27577 pointing to the given file.
27580 @defvr {Scheme Variable} setuid-program-service-type
27581 Type for the ``setuid-program service''. This service collects lists of
27582 executable file names, passed as gexps, and adds them to the set of
27583 setuid-root programs on the system (@pxref{Setuid Programs}).
27586 @defvr {Scheme Variable} profile-service-type
27587 Type of the service that populates the @dfn{system profile}---i.e., the
27588 programs under @file{/run/current-system/profile}. Other services can
27589 extend it by passing it lists of packages to add to the system profile.
27592 @cindex provenance tracking, of the operating system
27593 @defvr {Scheme Variable} provenance-service-type
27594 This is the type of the service that records @dfn{provenance meta-data}
27595 in the system itself. It creates several files under
27596 @file{/run/current-system}:
27600 This is a ``channel file'' that can be passed to @command{guix pull -C}
27601 or @command{guix time-machine -C}, and which describes the channels used
27602 to build the system, if that information was available
27603 (@pxref{Channels}).
27605 @item configuration.scm
27606 This is the file that was passed as the value for this
27607 @code{provenance-service-type} service. By default, @command{guix
27608 system reconfigure} automatically passes the OS configuration file it
27609 received on the command line.
27612 This contains the same information as the two other files but in a
27613 format that is more readily processable.
27616 In general, these two pieces of information (channels and configuration
27617 file) are enough to reproduce the operating system ``from source''.
27620 This information is necessary to rebuild your operating system, but it
27621 is not always sufficient. In particular, @file{configuration.scm}
27622 itself is insufficient if it is not self-contained---if it refers to
27623 external Guile modules or to extra files. If you want
27624 @file{configuration.scm} to be self-contained, we recommend that modules
27625 or files it refers to be part of a channel.
27627 Besides, provenance meta-data is ``silent'' in the sense that it does
27628 not change the bits contained in your system, @emph{except for the
27629 meta-data bits themselves}. Two different OS configurations or sets of
27630 channels can lead to the same system, bit-for-bit; when
27631 @code{provenance-service-type} is used, these two systems will have
27632 different meta-data and thus different store file names, which makes
27633 comparison less trivial.
27636 This service is automatically added to your operating system
27637 configuration when you use @command{guix system reconfigure},
27638 @command{guix system init}, or @command{guix deploy}.
27641 @node Shepherd Services
27642 @subsection Shepherd Services
27644 @cindex shepherd services
27646 @cindex init system
27647 The @code{(gnu services shepherd)} module provides a way to define
27648 services managed by the GNU@tie{}Shepherd, which is the
27649 initialization system---the first process that is started when the
27650 system boots, also known as PID@tie{}1
27651 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
27653 Services in the Shepherd can depend on each other. For instance, the
27654 SSH daemon may need to be started after the syslog daemon has been
27655 started, which in turn can only happen once all the file systems have
27656 been mounted. The simple operating system defined earlier (@pxref{Using
27657 the Configuration System}) results in a service graph like this:
27659 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
27661 You can actually generate such a graph for any operating system
27662 definition using the @command{guix system shepherd-graph} command
27663 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
27665 The @code{%shepherd-root-service} is a service object representing
27666 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
27667 by passing it lists of @code{<shepherd-service>} objects.
27669 @deftp {Data Type} shepherd-service
27670 The data type representing a service managed by the Shepherd.
27673 @item @code{provision}
27674 This is a list of symbols denoting what the service provides.
27676 These are the names that may be passed to @command{herd start},
27677 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
27678 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
27679 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
27681 @item @code{requirement} (default: @code{'()})
27682 List of symbols denoting the Shepherd services this one depends on.
27684 @cindex one-shot services, for the Shepherd
27685 @item @code{one-shot?} (default: @code{#f})
27686 Whether this service is @dfn{one-shot}. One-shot services stop immediately
27687 after their @code{start} action has completed. @xref{Slots of services,,,
27688 shepherd, The GNU Shepherd Manual}, for more info.
27690 @item @code{respawn?} (default: @code{#t})
27691 Whether to restart the service when it stops, for instance when the
27692 underlying process dies.
27695 @itemx @code{stop} (default: @code{#~(const #f)})
27696 The @code{start} and @code{stop} fields refer to the Shepherd's
27697 facilities to start and stop processes (@pxref{Service De- and
27698 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
27699 G-expressions that get expanded in the Shepherd configuration file
27700 (@pxref{G-Expressions}).
27702 @item @code{actions} (default: @code{'()})
27703 @cindex actions, of Shepherd services
27704 This is a list of @code{shepherd-action} objects (see below) defining
27705 @dfn{actions} supported by the service, in addition to the standard
27706 @code{start} and @code{stop} actions. Actions listed here become available as
27707 @command{herd} sub-commands:
27710 herd @var{action} @var{service} [@var{arguments}@dots{}]
27713 @item @code{auto-start?} (default: @code{#t})
27714 Whether this service should be started automatically by the Shepherd. If it
27715 is @code{#f} the service has to be started manually with @code{herd start}.
27717 @item @code{documentation}
27718 A documentation string, as shown when running:
27721 herd doc @var{service-name}
27724 where @var{service-name} is one of the symbols in @code{provision}
27725 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
27727 @item @code{modules} (default: @code{%default-modules})
27728 This is the list of modules that must be in scope when @code{start} and
27729 @code{stop} are evaluated.
27734 @deftp {Data Type} shepherd-action
27735 This is the data type that defines additional actions implemented by a
27736 Shepherd service (see above).
27740 Symbol naming the action.
27742 @item documentation
27743 This is a documentation string for the action. It can be viewed by running:
27746 herd doc @var{service} action @var{action}
27750 This should be a gexp that evaluates to a procedure of at least one argument,
27751 which is the ``running value'' of the service (@pxref{Slots of services,,,
27752 shepherd, The GNU Shepherd Manual}).
27755 The following example defines an action called @code{say-hello} that kindly
27761 (documentation "Say hi!")
27762 (procedure #~(lambda (running . args)
27763 (format #t "Hello, friend! arguments: ~s\n"
27768 Assuming this action is added to the @code{example} service, then you can do:
27771 # herd say-hello example
27772 Hello, friend! arguments: ()
27773 # herd say-hello example a b c
27774 Hello, friend! arguments: ("a" "b" "c")
27777 This, as you can see, is a fairly sophisticated way to say hello.
27778 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
27782 @defvr {Scheme Variable} shepherd-root-service-type
27783 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
27785 This is the service type that extensions target when they want to create
27786 shepherd services (@pxref{Service Types and Services}, for an example).
27787 Each extension must pass a list of @code{<shepherd-service>}.
27790 @defvr {Scheme Variable} %shepherd-root-service
27791 This service represents PID@tie{}1.
27795 @node Documentation
27796 @chapter Documentation
27798 @cindex documentation, searching for
27799 @cindex searching for documentation
27800 @cindex Info, documentation format
27802 @cindex manual pages
27803 In most cases packages installed with Guix come with documentation.
27804 There are two main documentation formats: ``Info'', a browseable
27805 hypertext format used for GNU software, and ``manual pages'' (or ``man
27806 pages''), the linear documentation format traditionally found on Unix.
27807 Info manuals are accessed with the @command{info} command or with Emacs,
27808 and man pages are accessed using @command{man}.
27810 You can look for documentation of software installed on your system by
27811 keyword. For example, the following command searches for information
27812 about ``TLS'' in Info manuals:
27816 "(emacs)Network Security" -- STARTTLS
27817 "(emacs)Network Security" -- TLS
27818 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
27819 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
27824 The command below searches for the same keyword in man pages:
27828 SSL (7) - OpenSSL SSL/TLS library
27829 certtool (1) - GnuTLS certificate tool
27833 These searches are purely local to your computer so you have the
27834 guarantee that documentation you find corresponds to what you have
27835 actually installed, you can access it off-line, and your privacy is
27838 Once you have these results, you can view the relevant documentation by
27842 $ info "(gnutls)Core TLS API"
27852 Info manuals contain sections and indices as well as hyperlinks like
27853 those found in Web pages. The @command{info} reader (@pxref{Top, Info
27854 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
27855 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
27856 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
27857 Introduction}, for an introduction to Info navigation.
27859 @node Installing Debugging Files
27860 @chapter Installing Debugging Files
27862 @cindex debugging files
27863 Program binaries, as produced by the GCC compilers for instance, are
27864 typically written in the ELF format, with a section containing
27865 @dfn{debugging information}. Debugging information is what allows the
27866 debugger, GDB, to map binary code to source code; it is required to
27867 debug a compiled program in good conditions.
27869 The problem with debugging information is that is takes up a fair amount
27870 of disk space. For example, debugging information for the GNU C Library
27871 weighs in at more than 60 MiB. Thus, as a user, keeping all the
27872 debugging info of all the installed programs is usually not an option.
27873 Yet, space savings should not come at the cost of an impediment to
27874 debugging---especially in the GNU system, which should make it easier
27875 for users to exert their computing freedom (@pxref{GNU Distribution}).
27877 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
27878 mechanism that allows users to get the best of both worlds: debugging
27879 information can be stripped from the binaries and stored in separate
27880 files. GDB is then able to load debugging information from those files,
27881 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
27884 The GNU distribution takes advantage of this by storing debugging
27885 information in the @code{lib/debug} sub-directory of a separate package
27886 output unimaginatively called @code{debug} (@pxref{Packages with
27887 Multiple Outputs}). Users can choose to install the @code{debug} output
27888 of a package when they need it. For instance, the following command
27889 installs the debugging information for the GNU C Library and for GNU
27893 guix install glibc:debug guile:debug
27896 GDB must then be told to look for debug files in the user's profile, by
27897 setting the @code{debug-file-directory} variable (consider setting it
27898 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
27902 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
27905 From there on, GDB will pick up debugging information from the
27906 @code{.debug} files under @file{~/.guix-profile/lib/debug}.
27908 In addition, you will most likely want GDB to be able to show the source
27909 code being debugged. To do that, you will have to unpack the source
27910 code of the package of interest (obtained with @code{guix build
27911 --source}, @pxref{Invoking guix build}), and to point GDB to that source
27912 directory using the @code{directory} command (@pxref{Source Path,
27913 @code{directory},, gdb, Debugging with GDB}).
27915 @c XXX: keep me up-to-date
27916 The @code{debug} output mechanism in Guix is implemented by the
27917 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
27918 opt-in---debugging information is available only for the packages
27919 with definitions explicitly declaring a @code{debug} output. This may be
27920 changed to opt-out in the future if our build farm servers can handle
27921 the load. To check whether a package has a @code{debug} output, use
27922 @command{guix package --list-available} (@pxref{Invoking guix package}).
27925 @node Security Updates
27926 @chapter Security Updates
27928 @cindex security updates
27929 @cindex security vulnerabilities
27930 Occasionally, important security vulnerabilities are discovered in software
27931 packages and must be patched. Guix developers try hard to keep track of
27932 known vulnerabilities and to apply fixes as soon as possible in the
27933 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
27934 containing only security updates.) The @command{guix lint} tool helps
27935 developers find out about vulnerable versions of software packages in the
27940 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
27941 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
27942 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
27946 @xref{Invoking guix lint}, for more information.
27948 Guix follows a functional
27949 package management discipline (@pxref{Introduction}), which implies
27950 that, when a package is changed, @emph{every package that depends on it}
27951 must be rebuilt. This can significantly slow down the deployment of
27952 fixes in core packages such as libc or Bash, since basically the whole
27953 distribution would need to be rebuilt. Using pre-built binaries helps
27954 (@pxref{Substitutes}), but deployment may still take more time than
27958 To address this, Guix implements @dfn{grafts}, a mechanism that allows
27959 for fast deployment of critical updates without the costs associated
27960 with a whole-distribution rebuild. The idea is to rebuild only the
27961 package that needs to be patched, and then to ``graft'' it onto packages
27962 explicitly installed by the user and that were previously referring to
27963 the original package. The cost of grafting is typically very low, and
27964 order of magnitudes lower than a full rebuild of the dependency chain.
27966 @cindex replacements of packages, for grafts
27967 For instance, suppose a security update needs to be applied to Bash.
27968 Guix developers will provide a package definition for the ``fixed''
27969 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
27970 Packages}). Then, the original package definition is augmented with a
27971 @code{replacement} field pointing to the package containing the bug fix:
27978 (replacement bash-fixed)))
27981 From there on, any package depending directly or indirectly on Bash---as
27982 reported by @command{guix gc --requisites} (@pxref{Invoking guix
27983 gc})---that is installed is automatically ``rewritten'' to refer to
27984 @code{bash-fixed} instead of @code{bash}. This grafting process takes
27985 time proportional to the size of the package, usually less than a
27986 minute for an ``average'' package on a recent machine. Grafting is
27987 recursive: when an indirect dependency requires grafting, then grafting
27988 ``propagates'' up to the package that the user is installing.
27990 Currently, the length of the name and version of the graft and that of
27991 the package it replaces (@code{bash-fixed} and @code{bash} in the example
27992 above) must be equal. This restriction mostly comes from the fact that
27993 grafting works by patching files, including binary files, directly.
27994 Other restrictions may apply: for instance, when adding a graft to a
27995 package providing a shared library, the original shared library and its
27996 replacement must have the same @code{SONAME} and be binary-compatible.
27998 The @option{--no-grafts} command-line option allows you to forcefully
27999 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
28003 guix build bash --no-grafts
28007 returns the store file name of the original Bash, whereas:
28014 returns the store file name of the ``fixed'', replacement Bash. This
28015 allows you to distinguish between the two variants of Bash.
28017 To verify which Bash your whole profile refers to, you can run
28018 (@pxref{Invoking guix gc}):
28021 guix gc -R `readlink -f ~/.guix-profile` | grep bash
28025 @dots{} and compare the store file names that you get with those above.
28026 Likewise for a complete Guix system generation:
28029 guix gc -R `guix system build my-config.scm` | grep bash
28032 Lastly, to check which Bash running processes are using, you can use the
28033 @command{lsof} command:
28036 lsof | grep /gnu/store/.*bash
28040 @node Bootstrapping
28041 @chapter Bootstrapping
28043 @c Adapted from the ELS 2013 paper.
28045 @cindex bootstrapping
28047 Bootstrapping in our context refers to how the distribution gets built
28048 ``from nothing''. Remember that the build environment of a derivation
28049 contains nothing but its declared inputs (@pxref{Introduction}). So
28050 there's an obvious chicken-and-egg problem: how does the first package
28051 get built? How does the first compiler get compiled? Note that this is
28052 a question of interest only to the curious hacker, not to the regular
28053 user, so you can shamelessly skip this section if you consider yourself
28054 a ``regular user''.
28056 @cindex bootstrap binaries
28057 The GNU system is primarily made of C code, with libc at its core. The
28058 GNU build system itself assumes the availability of a Bourne shell and
28059 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
28060 `grep'. Furthermore, build programs---programs that run
28061 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
28062 (@pxref{Derivations}). Consequently, to be able to build anything at
28063 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
28064 Binutils, libc, and the other packages mentioned above---the
28065 @dfn{bootstrap binaries}.
28067 These bootstrap binaries are ``taken for granted'', though we can also
28068 re-create them if needed (more on that later).
28070 For @code{i686-linux} and @code{x86_64-linux} the Guix bootstrap process is
28071 more elaborate, @pxref{Reduced Binary Seed Bootstrap}.
28074 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
28075 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
28078 @node Reduced Binary Seed Bootstrap
28079 @section The Reduced Binary Seed Bootstrap
28081 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
28082 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
28083 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
28084 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
28085 ``taken for granted.''
28087 Taking these binaries for granted means that we consider them to be a correct
28088 and trustworthy `seed' for building the complete system. Therein lies a
28089 problem: the current combined size of these bootstrap binaries is about 250MB
28090 (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing or even inspecting
28091 these is next to impossible.
28093 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a ``Reduced
28094 Binary Seed'' bootstrap @footnote{We would like to say: ``Full Source
28095 Bootstrap'' and while we are working towards that goal it would be hyperbole
28096 to use that term for what we do now.}.
28098 The Reduced Binary Seed bootstrap removes the most critical tools---from a
28099 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
28100 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
28101 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
28102 written in Scheme and the Mes C Library, built for TinyCC and for GCC). Using
28103 these new binary seeds and a new set of
28105 packages@footnote{@c
28120 gcc-mesboot1-wrapper,
28121 glibc-headers-mesboot,
28125 gcc-mesboot-wrapper.
28128 the ``missing'' Binutils, GCC, and the GNU C Library are built from source.
28129 From here on the more traditional bootstrap process resumes. This approach
28130 has reduced the bootstrap binaries in size to about 130MB. Work is ongoing to
28131 reduce this further. If you are interested, join us on @code{#bootstrappable}
28132 on the Freenode IRC network.
28134 @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
28135 @c dot -T png doc/images/gcc-mesboot-bag-graph.dot > doc/images/gcc-mesboot-bag-graph.png
28137 Below is the generated dependency graph for @code{gcc-mesboot}, the bootstrap
28138 compiler used to build the rest of GuixSD.
28140 @image{images/gcc-mesboot-bag-graph,6in,,Dependency graph of the gcc-mesboot}
28142 @node Preparing to Use the Bootstrap Binaries
28143 @section Preparing to Use the Bootstrap Binaries
28145 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
28146 @c large image, it's hard to scroll. Oh well.
28147 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
28149 The figure above shows the very beginning of the dependency graph of the
28150 distribution, corresponding to the package definitions of the @code{(gnu
28151 packages bootstrap)} module. A similar figure can be generated with
28152 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
28155 guix graph -t derivation \
28156 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
28157 | dot -Tps > gcc.ps
28160 or, for the Reduced Binary Seed bootstrap
28163 guix graph -t derivation \
28164 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
28165 | dot -Tps > mes.ps
28168 At this level of detail, things are
28169 slightly complex. First, Guile itself consists of an ELF executable,
28170 along with many source and compiled Scheme files that are dynamically
28171 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
28172 tarball shown in this graph. This tarball is part of Guix's ``source''
28173 distribution, and gets inserted into the store with @code{add-to-store}
28174 (@pxref{The Store}).
28176 But how do we write a derivation that unpacks this tarball and adds it
28177 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
28178 derivation---the first one that gets built---uses @code{bash} as its
28179 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
28180 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
28181 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
28182 the Guix source distribution, whose sole purpose is to allow the Guile
28183 tarball to be unpacked.
28185 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
28186 Guile that can be used to run subsequent build programs. Its first task
28187 is to download tarballs containing the other pre-built binaries---this
28188 is what the @code{.tar.xz.drv} derivations do. Guix modules such as
28189 @code{ftp-client.scm} are used for this purpose. The
28190 @code{module-import.drv} derivations import those modules in a directory
28191 in the store, using the original layout. The
28192 @code{module-import-compiled.drv} derivations compile those modules, and
28193 write them in an output directory with the right layout. This
28194 corresponds to the @code{#:modules} argument of
28195 @code{build-expression->derivation} (@pxref{Derivations}).
28197 Finally, the various tarballs are unpacked by the derivations
28198 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
28199 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
28200 point we have a working C tool chain.
28202 @unnumberedsec Building the Build Tools
28204 Bootstrapping is complete when we have a full tool chain that does not
28205 depend on the pre-built bootstrap tools discussed above. This
28206 no-dependency requirement is verified by checking whether the files of
28207 the final tool chain contain references to the @file{/gnu/store}
28208 directories of the bootstrap inputs. The process that leads to this
28209 ``final'' tool chain is described by the package definitions found in
28210 the @code{(gnu packages commencement)} module.
28212 The @command{guix graph} command allows us to ``zoom out'' compared to
28213 the graph above, by looking at the level of package objects instead of
28214 individual derivations---remember that a package may translate to
28215 several derivations, typically one derivation to download its source,
28216 one to build the Guile modules it needs, and one to actually build the
28217 package from source. The command:
28220 guix graph -t bag \
28221 -e '(@@@@ (gnu packages commencement)
28222 glibc-final-with-bootstrap-bash)' | dot -Tps > t.ps
28226 produces the dependency graph leading to the ``final'' C
28227 library@footnote{You may notice the @code{glibc-intermediate} label,
28228 suggesting that it is not @emph{quite} final, but as a good
28229 approximation, we will consider it final.}, depicted below.
28231 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
28233 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
28234 The first tool that gets built with the bootstrap binaries is
28235 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
28236 for all the following packages. From there Findutils and Diffutils get
28239 Then come the first-stage Binutils and GCC, built as pseudo cross
28240 tools---i.e., with @code{--target} equal to @code{--host}. They are
28241 used to build libc. Thanks to this cross-build trick, this libc is
28242 guaranteed not to hold any reference to the initial tool chain.
28244 From there the final Binutils and GCC (not shown above) are built.
28246 from the final Binutils, and links programs against the just-built libc.
28247 This tool chain is used to build the other packages used by Guix and by
28248 the GNU Build System: Guile, Bash, Coreutils, etc.
28250 And voilà! At this point we have the complete set of build tools that
28251 the GNU Build System expects. These are in the @code{%final-inputs}
28252 variable of the @code{(gnu packages commencement)} module, and are
28253 implicitly used by any package that uses @code{gnu-build-system}
28254 (@pxref{Build Systems, @code{gnu-build-system}}).
28257 @unnumberedsec Building the Bootstrap Binaries
28259 @cindex bootstrap binaries
28260 Because the final tool chain does not depend on the bootstrap binaries,
28261 those rarely need to be updated. Nevertheless, it is useful to have an
28262 automated way to produce them, should an update occur, and this is what
28263 the @code{(gnu packages make-bootstrap)} module provides.
28265 The following command builds the tarballs containing the bootstrap binaries
28266 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
28267 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
28268 and Guile, and a tarball containing a mixture of Coreutils and other basic
28269 command-line tools):
28272 guix build bootstrap-tarballs
28275 The generated tarballs are those that should be referred to in the
28276 @code{(gnu packages bootstrap)} module mentioned at the beginning of
28279 Still here? Then perhaps by now you've started to wonder: when do we
28280 reach a fixed point? That is an interesting question! The answer is
28281 unknown, but if you would like to investigate further (and have
28282 significant computational and storage resources to do so), then let us
28285 @unnumberedsec Reducing the Set of Bootstrap Binaries
28287 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
28288 binary code! Why is that a problem? It's a problem because these big chunks
28289 of binary code are practically non-auditable, which makes it hard to establish
28290 what source code produced them. Every unauditable binary also leaves us
28291 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
28292 paper @emph{Reflections on Trusting Trust}.
28294 This is mitigated by the fact that our bootstrap binaries were generated
28295 from an earlier Guix revision. Nevertheless it lacks the level of
28296 transparency that we get in the rest of the package dependency graph,
28297 where Guix always gives us a source-to-binary mapping. Thus, our goal
28298 is to reduce the set of bootstrap binaries to the bare minimum.
28300 The @uref{http://bootstrappable.org, Bootstrappable.org web site} lists
28301 on-going projects to do that. One of these is about replacing the
28302 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
28303 of increasing complexity, which could be built from source starting from
28304 a simple and auditable assembler.
28306 Our first major achievement is the replacement of of GCC, the GNU C Library
28307 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
28308 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
28309 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
28310 bootstrapped yet and thus we inject them as binary seeds. We call this the
28311 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
28312 binaries! Also, it has eliminated the C compiler binary; i686-linux and
28313 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
28315 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
28316 also looking at any other bootstrap binaries. Your help is welcome!
28319 @chapter Porting to a New Platform
28321 As discussed above, the GNU distribution is self-contained, and
28322 self-containment is achieved by relying on pre-built ``bootstrap
28323 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
28324 operating system kernel, CPU architecture, and application binary
28325 interface (ABI). Thus, to port the distribution to a platform that is
28326 not yet supported, one must build those bootstrap binaries, and update
28327 the @code{(gnu packages bootstrap)} module to use them on that platform.
28329 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
28330 When everything goes well, and assuming the GNU tool chain supports the
28331 target platform, this can be as simple as running a command like this
28335 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
28338 For this to work, the @code{glibc-dynamic-linker} procedure in
28339 @code{(gnu packages bootstrap)} must be augmented to return the right
28340 file name for libc's dynamic linker on that platform; likewise,
28341 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
28342 taught about the new platform.
28344 Once these are built, the @code{(gnu packages bootstrap)} module needs
28345 to be updated to refer to these binaries on the target platform. That
28346 is, the hashes and URLs of the bootstrap tarballs for the new platform
28347 must be added alongside those of the currently supported platforms. The
28348 bootstrap Guile tarball is treated specially: it is expected to be
28349 available locally, and @file{gnu/local.mk} has rules to download it for
28350 the supported architectures; a rule for the new platform must be added
28353 In practice, there may be some complications. First, it may be that the
28354 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
28355 above) is not recognized by all the GNU tools. Typically, glibc
28356 recognizes some of these, whereas GCC uses an extra @code{--with-abi}
28357 configure flag (see @code{gcc.scm} for examples of how to handle this).
28358 Second, some of the required packages could fail to build for that
28359 platform. Lastly, the generated binaries could be broken for some
28362 @c *********************************************************************
28363 @include contributing.texi
28365 @c *********************************************************************
28366 @node Acknowledgments
28367 @chapter Acknowledgments
28369 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
28370 which was designed and
28371 implemented by Eelco Dolstra, with contributions from other people (see
28372 the @file{nix/AUTHORS} file in Guix.) Nix pioneered functional package
28373 management, and promoted unprecedented features, such as transactional
28374 package upgrades and rollbacks, per-user profiles, and referentially
28375 transparent build processes. Without this work, Guix would not exist.
28377 The Nix-based software distributions, Nixpkgs and NixOS, have also been
28378 an inspiration for Guix.
28380 GNU@tie{}Guix itself is a collective work with contributions from a
28381 number of people. See the @file{AUTHORS} file in Guix for more
28382 information on these fine people. The @file{THANKS} file lists people
28383 who have helped by reporting bugs, taking care of the infrastructure,
28384 providing artwork and themes, making suggestions, and more---thank you!
28387 @c *********************************************************************
28388 @node GNU Free Documentation License
28389 @appendix GNU Free Documentation License
28390 @cindex license, GNU Free Documentation License
28391 @include fdl-1.3.texi
28393 @c *********************************************************************
28394 @node Concept Index
28395 @unnumbered Concept Index
28398 @node Programming Index
28399 @unnumbered Programming Index
28400 @syncodeindex tp fn
28401 @syncodeindex vr fn
28406 @c Local Variables:
28407 @c ispell-local-dictionary: "american";